JP2004311390A - DC relay - Google Patents

Abstract

A DC relay having a simple structure and capable of shutting down DC high voltage in a short time while being small in size is provided.
An input contact, an output contact, and an intermediate member connectable to the two contacts are provided. The intermediate member includes a main intermediate member 3 that allows current to flow from the input contact 1 to the output contact 2 when the relay is energized, and an input contact 1 to an output contact when the main intermediate member 3 is separated from the input contact 1 and the output contact 2. And a sub-intermediate member (4) for supplying current to (2). The electric resistance value of the sub intermediate member 4 is larger than the electric resistance value of the main intermediate member 3.
[Selection diagram] Fig. 1

Description

  The present invention relates to a direct current relay. In particular, the present invention relates to a DC relay that can reliably cut off DC current with a simple structure.

  In recent years, high-voltage (about 300 V) vehicles such as hybrid vehicles and fuel cell vehicles have been developed due to environmental problems. These vehicles are equipped with a control circuit comprising a DC high voltage main battery and a high voltage circuit.

  Further, since the main battery has a high DC voltage, it is necessary to disconnect the battery from the control circuit in the event of an accident or the like, and a DC relay having mechanical contacts is provided between the battery and the control circuit.

  These relays have a very low breaking speed because the arc generated when breaking a DC high voltage is very large, and it is very difficult to break in a short time. Therefore, conventionally, a structure has been proposed in which a gas having a large cooling effect such as hydrogen is sealed in an arc generating portion to suppress generation of an arc (for example, see Patent Document 1).

JP-A-9-320411

  By the way, the arc has a high temperature of several thousand degrees Celsius to 10,000 degrees Celsius, and as shown in Patent Document 1, in the case of a structure that suppresses the generation of the arc with a gas, a case structure that can completely seal the gas is required. And In this case, the case requires heat resistance due to the arc and is expensive (for example, ceramic). Further, it is necessary to take a structure that maintains gas tightness without maintenance for a long period of time while considering heat resistance due to the arc.

  However, the structure for maintaining gas tightness is very difficult and costly. In addition, in order to increase the airtightness and heat resistance, the case must be extremely thick in order to increase the area of the sealed joint of the case, so that the size of the case increases.

  As described above, when a gas such as hydrogen is sealed, a case is required to be large in order to maintain a state in which the gas is sealed for a long time, and the case structure is complicated. As a result, it has been extremely difficult to reduce the size of a device mounted in a limited space such as an automobile without reducing performance.

  Accordingly, an object of the present invention is to provide a DC relay that can cut off DC high voltage in a short time without increasing the size of the entire relay.

  The present invention provides two types of intermediate members having different electric resistance values between an input contact and an output contact. When a relay is energized, current flows from an input contact to an output contact via a low resistance intermediate member. When the current flows from the input contact to the output contact via the high resistance intermediate member, the relay is completely shut off. By interrupting the relay in this way, the above-described object is achieved by reducing the arc energy generated at the contact at the time of interrupting.

  That is, the present invention includes an input contact, an output contact, and an intermediate member capable of connecting the two contacts. The intermediate member includes a main intermediate member and a sub intermediate member having different electric resistance values.

  The main intermediate member is used for flowing a current from the input contact to the output contact when the relay is energized. The sub intermediate member is used for flowing a current from the input contact to the output contact when the main intermediate member is separated from the input contact and the output contact. Then, the electric resistance value of the sub intermediate member is made larger than the electric resistance value of the main intermediate member.

  Further, the main intermediate member and the sub intermediate member may be directly connected to the input contact and the output contact, or the input contact may be connected to the intermediate member via the input side connection contact, and the output contact may be output. It may be possible to connect to the intermediate member via the side connection contact.

  Further, the main intermediate member is an intermediate contact that is electrically connected or disconnected with respect to the input contact and the output contact or with respect to the input-side connection contact and the output-side connection contact. Since the main intermediate member is an intermediate contact, the main intermediate member has a contact portion that makes contact with the input contact or the input side connection contact, and a contact portion that makes contact with the output contact or the output side connection contact.

  The main intermediate member is preferably formed in, for example, a U-shape or a shape. In the case of a U-shape or the like, both ends of the U-shape or] are contact portions, and the end faces of these contact portions are in contact with the input contact and the output contact, or the input-side connection contact and the output-side connection contact. Let it do.

  The sub intermediate member may be an intermediate contact that is electrically connected or disconnected with respect to the input contact and the output contact, or with respect to the input side connection contact and the output side connection contact. Further, both ends of the sub intermediate member may be fixed to the input contact and the output contact, or the input side connection contact and the output side connection contact, or may be kept in contact with each other.

  The sub intermediate member can be formed in, for example, a rectangular flat plate shape. In the case of a flat plate, one end in the longitudinal direction of the flat plate is brought into contact with the input contact or the input side connecting contact, and the other end in the longitudinal direction is brought into contact with the output contact or the output side connecting contact.

  External terminals are connected to the input contact and the output contact. The input and output contacts can be L-shaped or columnar. When the main intermediate member and the sub intermediate member are used as intermediate contacts, they are preferably L-shaped in order to connect them to the input contact and the output contact, respectively.

  When the input contact and the output contact are formed in a columnar shape, the input contact can be connected to the intermediate member via the input side connection contact, and the output contact can be connected to the intermediate member via the output side connection contact. be able to.

  The electric resistance value of the sub intermediate member is larger than the electric resistance value of the main intermediate member as described above. However, the electric resistance value of the sub-intermediate member is such that when a current flows while both the main intermediate member and the sub-intermediate member are connected to the input contact and the output contact, the electric current hardly flows through the sub-intermediate member. Value (high resistance value), or an electric resistance value at which current flows (low resistance value).

  In the present invention, a method of connecting the sub intermediate member to the input contact and the output contact differs depending on the magnitude of the electric resistance value of the sub intermediate member.

  First, when the electric resistance value of the sub intermediate member is high, when the relay is energized, the main intermediate member and the sub intermediate member are connected to the input contact and the output contact, and the relay is turned off. Then, the main intermediate member, the sub intermediate member, the input contact, and the output contact are separated.

  Specifically, for example, when the main intermediate member and the sub-intermediate member are intermediate contacts that are conductive or interrupted with respect to the input contact and the output contact, when the relay is energized, the main intermediate member and the sub-intermediate member To the input and output contacts.

  At this time, when the relay is energized, even if the sub intermediate member is connected to the input contact and the output contact, most of the current flows through the main intermediate member, and almost no current flows through the sub intermediate member.

  When the relay is cut off, the main intermediate member is disconnected from the input contact and the output contact, and then, after a lapse of a predetermined time, the sub intermediate member is disconnected from the input contact and the output contact.

  When the relay is interrupted, current flows from the input contact to the output contact via the sub-intermediate member when the main intermediate member is disconnected from the input and output contacts. At this time, the current is subjected to resistance by the sub intermediate member, and energy is consumed. As a result, the arc generated between the main intermediate member and the input and output contacts becomes very small, or almost no arc is generated.

  Furthermore, the sub intermediate member is completely disconnected from the input contact and the output contact after the resistance is given to the electric current by the sub intermediate member and the energy is consumed, so that at the time of this separation, the sub intermediate member, the input contact and the output contact Can also be very small or very little.

  When the electric resistance value of the sub intermediate member is low, for example, when both intermediate members are intermediate contacts, only the main intermediate member is connected to the input contact and the output contact when the relay is energized, and the sub intermediate The member is separated from the input and output contacts.

  When disconnecting the relay, the sub-intermediate member is connected to the input contact and the output contact immediately before disconnecting the main intermediate member from the input contact and the output contact. Then, after the main intermediate member is separated from the input contact and the output contact, and after a predetermined time has elapsed, the sub intermediate member is separated from the input contact and the output contact.

  Again, when the main intermediate member is disconnected from the input and output contacts, current flows through the sub-intermediate member, consuming energy and reducing arc energy.

  As described above, according to the present invention, when the relay is energized, the current flows in series in the order of the input contact, the main intermediate member, and the output contact. When the main intermediate member is separated from the input contact and the output contact, a current flows from the input contact to the output contact via the sub intermediate member for a predetermined time, so that energy is consumed.

  Here, various drive sources can be used to open and close the contacts. A motor can be used for the rotary drive source, and a solenoid or cylinder can be used for the linear drive source. In the case of using a rotating system drive source, the contacts are driven via a conversion mechanism that converts a rotary motion into a reciprocating motion. When a linear drive source is used, the linear drive source is connected to the contact to drive the contact.

  When the main intermediate member and the sub intermediate member are intermediate contacts that are electrically connected or disconnected from the input contact and the output contact, these intermediate members are used as movable contacts.

  At this time, the main intermediate member can be driven to open and close by the main drive means, and the sub intermediate member can be driven to open and close by the sub drive means.

  It is preferable that each of the main drive unit and the sub drive unit is constituted by a solenoid. When two driving units are provided as described above, each driving unit is driven at a different timing by using the control unit.

  Since the two drive units are individually driven, it is possible to finely set the timing of the opening and closing drive of each. Further, the timing can be adjusted according to the operating condition (for example, current value). As described above, by providing the main drive unit and the sub drive unit, the breaking performance of the relay can be further improved.

  When the main drive unit and the sub drive unit are provided, the opening / closing drive timing can be set by using an RC circuit including a resistor R and a capacitor C, or by using a timer to set the opening operation timing.

  When the RC circuit is used, a resistor R and a capacitor C are provided between the main drive unit and the sub drive unit. Then, first, a current flows through the main drive unit to open the main intermediate member. At the same time, a current also flows through the sub drive unit. However, while the capacitor C is charged via the resistor R, a current flows through the sub drive unit. The amount is reduced. As a result, the operation of the sub-side driving unit is delayed more than the main-side driving unit, and the sub-intermediate member opens later than the main intermediate member.

  Further, a control means for detecting a current amount of the DC relay immediately before the cutoff and opening the sub-intermediate member by the sub-side driving means in accordance with the detected current amount is provided, and the timing of the opening operation is freely set. You can also.

  Further, the main intermediate member and the sub intermediate member can be driven to open and close with a time difference by one driving unit. In this case, it is preferable that both intermediate members open in the same direction. To open in the opposite direction, a gear or a link mechanism is used.

  For example, each of the main intermediate member and the sub intermediate member is provided with a projection protruding in a direction orthogonal to the opening / closing direction, and an engagement portion is provided on the drive shaft of the solenoid so as to contact these projections stepwise to press the projections. Then, first, the engaging portion is engaged with the projection of the main intermediate member to open the main intermediate member, and then the other intermediate portion is engaged with the projection of the sub intermediate member to open the sub intermediate member. Let it do.

  Further, as another means for opening and closing the two intermediate members by one driving means, a sub intermediate member is interposed between a part of the main intermediate member and an input contact and an output contact, and the main intermediate member and the sub intermediate member are interposed. One in which an elastic member and a connecting rod are disposed between members.

  In this case, the sub intermediate member is urged toward the input contact and the output contact by the elastic member. As the elastic member, a coil spring is preferable. One end of the connecting rod is fixed to the sub intermediate member, and the other end connects the sub intermediate member to the main intermediate member so as to be movable with respect to the main intermediate member. The connecting rod is inserted into the coil spring, and a through hole is formed in the main intermediate member so that the connecting rod is loosely inserted into the hole. A stopper is provided at the end of the connecting rod to prevent the connecting rod from coming out of the hole.

  Then, the main intermediate member is driven to be opened and closed by the solenoid. When the main intermediate member is in contact with the input contact and the output contact, and for a predetermined time from the start of the opening operation of the main intermediate member, the sub intermediate member is brought into contact with the input contact and the output contact by the biasing force of the elastic member. To keep. After a lapse of a predetermined time from the start of the opening operation of the main intermediate member, the sub intermediate member is separated from the input contact and the output contact in synchronization with the operation of the main intermediate member via the connecting rod.

  As described above, when the main intermediate member is driven by the solenoid, the opening operation of the sub intermediate member is started after a lapse of a predetermined time from the opening operation of the main intermediate member by the elastic member and the connecting rod. As described above, since the main intermediate member and the sub intermediate member can be driven by one driving unit, the driving unit can be downsized.

  Further, the present invention provides an input contact that can be connected to an intermediate member through an input-side connection contact, an output contact that can be connected to an intermediate member through an output-side connection contact, and a main intermediate member that has an input-side connection contact and an output. It may be an intermediate contact that is conductive or disconnected from the side connection contact.

  In this case, the input contact, the output contact, and the main intermediate member are disposed so as to sandwich the input-side connection contact and the output-side connection contact. Then, the sub intermediate member is fixed or connected between the input side connection contact and the output side connection contact, and the sub intermediate member, the input side connection contact, and the output side connection contact are fixed contacts. It is preferable that the intermediate member and the movable contact be a movable contact. The input contact and the output contact open in the same direction, and the main intermediate member opens in the opposite direction.

  When the relay is energized, the main intermediate member and the sub intermediate member are connected to the input contact and the output contact via the input side connection contact and the output side connection contact. When the relay is cut off, the main intermediate member is separated from the input side connection contact and the output side connection contact. After a lapse of a predetermined time, the input contact is disconnected from the input side connection contact, and the output contact is disconnected from the output side connection contact.

  Further, the input contact and the output contact are fixed contacts, and the input side connection contact and the output side connection contact are fixed and integrated with the sub intermediate member, and the integrated sub intermediate member and main intermediate member are movable contacts. You can also. In this case, the two intermediate members can be driven to open and close by one driving unit.

  Further, the present invention is configured to include an input contact, an input side connection contact, an output contact, an output side connection contact, and an intermediate member. When the main intermediate member is an intermediate contact, when the relay is cut off, the main intermediate member, the input The contact, the output contact, the input-side connection contact, and the output-side connection contact can all be disconnected simultaneously.

  That is, the input contact, the output contact, and the main intermediate member are arranged so as to open on the same side and in the same direction with respect to the input side connection contact and the output side connection contact. Then, the sub intermediate member is connected or fixed so as to be connected to the input side connection contact and the output side connection contact.

  In this case, the input contact, the output contact, and the main intermediate member can be movable contacts, and the input-side connection contact, the output-side connection contact, and the sub-intermediate member can be fixed contacts. Further, the input contact, the output contact, and the main intermediate member may be fixed contacts, and the input-side connection contact, the output-side connection contact, and the sub-intermediate member may be movable contacts.

  When the relay is energized, the main intermediate member and the sub intermediate member are connected to the input contact and the output contact via the input side connection contact and the output side connection contact. When the relay is cut off, the input contact, the output contact, and the main intermediate member are simultaneously disconnected from the input side connection contact and the output side connection contact.

  With this configuration, while the input contact, the output contact, and the main intermediate member are driven at a time to cut off the relay, the energy of the current can be consumed by the resistance of the sub intermediate member. As a result, the arc generated between the contacts can be reduced as much as possible while simplifying the configuration of the relay.

  When the sub intermediate member is fixed to the input side connection contact and the output side connection contact, the sub intermediate member, the input side connection contact, and the output side connection contact can be made into one member. The movable contact can be constituted by two members. As a result, the configuration of the driving means can be simplified.

  Further, in such a configuration, when the electric resistance value of the sub-intermediate member is low, when the relay is energized, the sub-intermediate member is separated from the input-side connecting contact and the output-side connecting contact, and the relay is turned off. It is preferable to connect the sub-intermediate member to the input-side connection contact and the output-side connection contact a predetermined time before the start of the shutoff operation. By doing so, it is possible to prevent a current from flowing to the sub intermediate member during energization.

  Further, at this time, it is preferable to provide a driving means for opening and closing the input-side connection contact and the output-side connection contact in conjunction with the driving of the sub intermediate member. Specifically, the tip of the drive shaft of the solenoid is fixed to the sub-intermediate member, and when the solenoid is in the advanced state, the sub-intermediate member does not contact the input-side connection contact and the output-side connection contact. deep. Then, the sub intermediate member comes into contact with the input side connection contact and the output side connection contact by the opening operation by the solenoid, and is pushed as it is by the sub intermediate member, so that the input side connection contact and the output side connection contact become the input contact, the output contact and the main contact. Be separated from the intermediate member.

  With such a configuration, the input-side connection contact and the output-side connection contact can also be opened by the driving unit that drives the sub intermediate member.

  Further, in each of the above-described configurations, it is preferable that a magnet for distorting an arc generated between the contacts by a magnetic field when the main intermediate member is cut off from the input contact and the output contact is provided.

  In the present invention, when the contacts are cut off, an arc generated between the contacts due to the magnetic field of the magnet is blown off in a predetermined direction with respect to the contact surface of the contacts.

  By providing the magnet in this way, the arc energy is consumed by stretching the arc by the magnet while consuming electric energy in the sub-intermediate member, so that the voltage of the arc is further increased and the relay is activated in a short time. It becomes possible to shut off.

  Further, the contact surface of the contact, the contact surface of the main intermediate member with the contact, and the contact surface of the sub intermediate member with the contact are composed of Ag having a chemical composition containing 1 to 9% by mass of Sn and 1 to 9% by mass of In. Made of an alloy, having a first layer on the surface and a second layer on the inside, the micro Vickers hardness of the first layer is 190 or more, the micro Vickers hardness of the second layer is 130 or less, the thickness of the first layer Is preferably in the range of 10 to 360 μm.

  The reason why the content of Sn is set to 1 to 9% by mass is that when the content is less than 1% by mass, the welding resistance of the contact decreases, and when the content exceeds 9% by mass, the temperature characteristic of the contact deteriorates. Preferably, it is 2 to 7% by mass.

  Here, the welding resistance property refers to a state in which the contact cannot be broken, particularly, the occurrence of welding in which the contact does not separate from the contact. The temperature characteristics refer to the degree of temperature rise of the contacts when energized, and the good temperature characteristics mean that the temperature of the contacts is unlikely to rise due to energization, and the thermal effects on cables and equipment connected to the relay It is difficult to give.

  The reason why the content of In is set to 1 to 9% by mass is that if the content is out of this range, the temperature characteristics of the contact point deteriorate, and if the content exceeds 9% by mass, it depends on the content of Sn. However, this is because the welding resistance is reduced. Preferably, it is 3 to 7% by mass.

  The reason why the hardness of the first layer (usually a load of 5 g) is 190 or more in terms of micro Vickers hardness is that if the hardness is less than this level, the welding resistance and the temperature characteristics are reduced. The reason for setting the hardness to 130 or less is that if the hardness exceeds this level, the contacts become brittle and the wear resistance decreases.

  Preferably, the hardness of the first layer is 240 or more and that of the second layer is 120 or less. In the present invention, the hardness is determined by micro-Vickers hardness at an arbitrary point in each of the first layer and the second layer on a cross section perpendicular to the surface of the contact. In the present invention, the contact may have a hardness distribution in each of the first layer and the second layer.

  Also, there is usually a hardness drop (micro Vickers hardness of 60 or more) at the boundary between the first layer and the second layer, and the boundary has an intermediate hardness between the two layers (that is, the hardness is the lower limit hardness of the first layer). (Hereinafter, referred to as an intermediate portion).

  The thickness of the first layer is 10 to 360 μm. If the amount is less than the lower limit, the welding resistance characteristics and the temperature characteristics decrease, and if the amount exceeds the upper limit, the temperature characteristics of the contact point deteriorate. Preferably it is 30 to 120 μm. The contact portion having the first layer and the second layer includes a contact portion having an intermediate portion. In this case, the thickness of the intermediate portion is desirably 200 μm or less. If it exceeds 200 μm, the temperature characteristics of the contact are likely to be reduced. Preferably it is 100 μm or less.

  The contact portion may further include at least one element selected from the group consisting of Sb, Ca, Bi, Ni, Co, Zn, and Pb as a subsidiary component in addition to the basic component. Usually, most of these components are dispersed in the form of compounds, especially oxides, in the Ag matrix.

  However, the desired dispersion range varies depending on the individual components. For example, 0.05 to 2 (Sb), 0.03 to 0.3 (Ca), 0.01 to 1 (Bi), 0.02 to 1.5 (Ni), 0.02 to 0.5 (Co), 0.02 to 8.5 in mass% units converted to elements. (Zn), 0.05 to 5 (Pb). The elements in parentheses are the target elements. In each of the above component types, if the amount is outside the above range, the temperature characteristics may decrease depending on the type of DC relay, and particularly when the amount exceeds the upper limit, the welding resistance characteristics also decrease depending on the type of relay. There is.

Usually, the above-mentioned auxiliary components slightly affect the performance of the contact, but other components include, for example, the following. Any of these may be included in trace amounts within the scope of the present invention. Although the desired content varies depending on the component, of the values in parentheses, those indicated by element symbols are expressed in units of mass% converted to elements, and those indicated by molecular formulas are expressed in units of mass% converted to the same molecule. This is the allowable upper limit. Ce (5), Li (5 ), Cr (5), Sr (5), Ti (5), Te (5), Mn (5), AlF 3 (5), CrF 3 (5) and CaF ₂ ( 5), Ge (3) and Ga (3), Si (0.5), Fe (0.1) and Mg (0.1).

  Examples of a method for producing the contact portion having the first layer and the second layer include a melting / casting method and a powder metallurgy method.

  For example, in the melting and casting method, the following procedures are available. First, an ingot melted and cast so as to have a chemical composition of each of the first layer and the second layer is produced, and these are roughly rolled, and then two types of rolled materials are hot pressed. At that time or thereafter, a thin connection layer such as the above-described pure Ag is pressure-bonded as necessary.

  This is further rolled to form a plate having a predetermined thickness, and then punched or further formed into an Ag alloy material having a size close to the final shape, and further, the material is internally oxidized (post-oxidation method) to form a Sn alloy. Converts metal components such as In and In into oxides.

  Prior to melting and casting, compounds other than oxides of the component elements may be included. In addition, if necessary, a step of adjusting the shape or heat treatment after the rolling is appropriately performed. In this case, by devising heat treatment conditions, it is possible to consciously control the microstructure of each layer and change the material characteristics and the level thereof.

  When the contact surface is formed by powder metallurgy, for example, a powder of Sn or In and a powder of Ag are blended and mixed in two predetermined compositions in advance, and then heat-treated for internal oxidation (pre-oxidation method). ), And the obtained two kinds of powders are laminated and filled in a mold, and compression molded to obtain a preform. The powder of Sn or In and the powder of Ag may be mixed with other compounds.

  Various plastic workings such as hot extrusion, hot / cold roll rolling, and hot forging can be applied to the preform. Further, similarly to the above-mentioned casting method, a step of adjusting the heat treatment and the shape after rolling is added as necessary. By controlling the heat treatment conditions, desired characteristics of each layer can be controlled.

  Also, after preparing only the material of the second layer by the procedure of melting and casting method or powder metallurgy method according to the above, the first layer, thermal spraying, thick film formation by CVD, etc., thick film printing by screen printing, etc. It may be formed by various means such as baking after application. Further, various means such as diffusion bonding by hot isostatic pressing and hot extrusion can be applied to the joining of the alloy plate constituting the first layer and the alloy plate constituting the second layer. In addition, by performing the heat treatment, the fine structure of each layer can be consciously controlled to obtain desired characteristics.

  Further, in the relay of the present invention, the Ag alloy material forming the contact portion is within the range of the above-mentioned conditions, and includes those in which the first layer and the second layer have the same chemical composition. When the first layer and the second layer have the same chemical composition, the hardness levels of both layers are made different by means described later.

  For example, there is a method in which only the first layer is rapidly heated / quenched so that the residual stress in the first layer is larger than that in the second layer, and a method in which only the first layer on the surface is shot-blasted and hardened.

  In addition, after performing so-called thermomechanical processing (thermal processing) on the Ag alloy plate in addition to hot rolling and cold rolling, and performing heat treatment, internal oxidation is performed, and a finer needle is formed on the first layer than on the second layer. There is a method of precipitating oxide particles in a shape and increasing the hardness of the surface. Also, there is a method in which when the Ag alloy sheets of the first layer and the second layer are rolled or hot pressed, the forging ratio of the first layer and the second layer is changed.

  Further, the material of the contact surface is within the range of the above-mentioned conditions, and further includes those in which the content of Sn in the first layer is the same as or higher than that of the second layer. Thereby, the hardness of the first layer is almost certainly higher than the hardness of the second layer.

  The contact surface is formed by a melting / casting method, a powder metallurgy method, or the like. At this time, it is preferable that the first layer and the second layer are internally oxidized. The internal oxidation method includes a post-oxidation method and a pre-oxidation method. The post-oxidation method is a method of performing internal oxidation after finishing the alloy to a final contact shape or forming the alloy close to the final contact shape. The pre-oxidation method is a method in which powder or grains of an alloy are internally oxidized, and then molded, compressed and sintered.

  As described above, according to the DC relay of the present invention, the following effects can be obtained.

  According to the present invention, the input contact and the output contact can be connected to two intermediate members having different electric resistances.When the relay is energized, a current flows through the low-resistance main intermediate member. The input contact and the output contact are separated from each other. At this time, a current is caused to flow also to the sub-intermediate member having a high resistance value.

  When the relay is turned off, the current flows through the sub-intermediate member, so that the current is consumed by the resistance of the sub-intermediate member. By causing a current to flow through the sub intermediate member, it is possible to reduce or prevent an arc generated between the main intermediate member and the input contact and the output contact or the input side connection contact and the output side connection contact.

  Furthermore, since the sub intermediate member and the input contact and the output contact are separated after giving the current resistance in the sub intermediate member and consuming the energy, the arc generated at the input contact and the output contact at the time of separation is small, or , Hardly occur.

  As described above, according to the present invention, it is possible to minimize the arc generated when the relay is cut off without sealing a gas such as hydrogen, without increasing the size of the relay case, and DC high voltage can be cut off in a short time. As a result, an airtight structure is not required, and a DC relay can be manufactured at low cost.

  In particular, when the relay of the present invention is used as a relay for turning on / off a high-voltage circuit in a high-voltage (about 300 V) vehicle such as a hybrid vehicle, the relay of the present invention is compact, and thus has a limited space. Can be used effectively.

  In addition, the relay of the present invention that can be miniaturized can be used for a unit that supplies DC current, such as a stationary fuel cell other than an automobile.

  Furthermore, by forming the contact surface of the contact, the contact surface of the main intermediate member with the contact, and the contact surface of the sub intermediate member with the contact with a material having excellent welding resistance, even if a large current flows during a short circuit, the contact can be formed. It is possible to reliably shut off without welding.

Hereinafter, embodiments of the present invention will be described.
(1st Embodiment)
FIG. 1 is a schematic configuration diagram showing a basic configuration of a relay according to a first embodiment of the present invention, and shows a step-by-step operation of relay shutoff. FIG. 2 is an explanatory view of a driving means for driving the movable contact of the relay to open and close.

  The relay of the present invention includes an input contact 1, an output contact 2, and a main intermediate member 3 and a sub intermediate member 4 enabling connection of the two contacts. In the first embodiment, the input contact 1 and the output contact 2 are fixed contacts, and the main intermediate member 3 and the sub intermediate member 4 are movable contacts. The main intermediate member 3 and the sub intermediate member 4 are intermediate contacts that come into contact with the input contact 1 and the output contact 2 or become non-contact.

  The input contact 1 and the output contact 2 are L-shaped, and contact portions 11, 21 for contacting the main intermediate member 3, contact portions 12, 22 for contacting the sub intermediate member 4, and external terminals are connected. Terminal connection portions 13 and 23.

  The main intermediate member 3 has a U-shape, and has a contact portion 31 at one end thereof for contacting the input contact 1 and a contact portion 32 at the other end thereof for contacting the output contact 2.

  The sub-intermediate member 4 is formed in a rectangular flat plate shape, as a contact portion 41 that makes one longitudinal end of the flat plate contact the input contact 1 and a contact portion 42 that makes the other longitudinal end contact the output contact 2. I have.

  The main intermediate member 3 and the sub intermediate member 4 have different electric resistance values, and the electric resistance value of the sub intermediate member 4 is larger than the electric resistance value of the main intermediate member 3. In this embodiment, when a current flows in a state where the main intermediate member 3 and the sub intermediate member 4 are connected to the input contact 1 and the output contact 2, the electric resistance value (high value) at which almost no current flows through the sub intermediate member 4 Resistance value).

  The main intermediate member 3 is used for flowing a current from the input contact 1 to the output contact 2 when the relay is energized. The sub intermediate member 4 is used for flowing a current from the input contact 1 to the output contact 2 when the main intermediate member 3 is separated from the input contact 1 and the output contact 2.

  In the present embodiment, the contact surfaces of the contact portions 11, 12, 21, 22, 31, 32, 41, and 42 each contain 1 to 9% by mass of Sn and 1 to 9% by mass of In. Ag alloy, having a first layer on the surface and a second layer inside, the first layer has a micro Vickers hardness of 190 or more, the second layer has a micro Vickers hardness of 130 or less, the first layer Is formed of a material having a thickness in the range of 10 to 360 μm. Specifically, at the input contact 1, the contact portion 11 with the main intermediate member 3, the contact portion 12 with the sub intermediate member 4, and the output contact 2 at the contact portion 21 with the main intermediate member 3 and the sub intermediate member 4. Contact part 22, the contact part 31 with the input contact 1 in the main intermediate member 3, the contact part 32 with the output contact 2, and the contact part 41 with the input contact 1 and the contact with the output contact 2 in the sub intermediate member 4. The contact surface of each contact portion called the portion 22 is formed of the above-mentioned specific material. The contact surfaces of the contact portions 11, 12, 21, 22, 31, 32, 41, and 42 are internally oxidized by a post-oxidation method in a chip state. For example, the chip is kept at 750 ° C. for 170 hours in an oxygen atmosphere at 4 atm (405.3 kPa).

  Note that the contact surfaces of the contact portions of the following second to fourth embodiments are also formed of the same material as that of the first embodiment. In the fifth embodiment and the seventh embodiment, the input contact 1 has a contact portion with a connection contact, the output contact 2 has a contact portion with a connection contact, the main intermediate member 3 has a contact portion with a connection contact, and a connection contact. In the first embodiment, the contact surfaces of the contact portions, that is, the contact portion with the input contact, the contact portion with the output contact, and the contact portion with the main intermediate member are formed of the same material as in the first embodiment. In the sixth embodiment, in addition to the fifth embodiment, the contact portions of the sub intermediate member 4 with the connecting contacts and the contact surfaces of the contact portions with the sub intermediate member 4 at the connecting contacts are also made of the same material as the first embodiment. Has formed.

  In the first embodiment, when the relay is energized, the main intermediate member 3 and the sub intermediate member 4 are connected to the input contact 1 and the output contact 2 (state of FIG. 1A). When the relay is cut off, the main intermediate member 3 is disconnected from the input contact 1 and the output contact 2 (the state of FIG. 1B), and after a lapse of a predetermined time, the sub intermediate member 4 is disconnected from the input contact 1 and the output contact 2. Disconnect (state c in FIG. 1).

  When the relay is energized (state a in FIG. 1), even if the sub intermediate member 4 is connected to the input contact 1 and the output contact 2, most of the current flows through the main intermediate member 3 and the sub intermediate member 4 Current hardly flows.

  When the relay is cut off, when the main intermediate member 3 is disconnected from the input contact 1 and the output contact 2, a current flows from the input contact 1 to the output contact 2 via the sub intermediate member 4 (see FIG. 1B). Status). At this time, the current is received by the sub intermediate member 4 and the energy is consumed. When the electric resistance value of the sub intermediate member 4 is considerably large, the arc generated between the main intermediate member 3 and the input contact 1 and the output contact 2 becomes very small or no arc is generated.

  Further, the sub intermediate member 4 is separated from the input contact 1 and the output contact 2 after the resistance is given to the current by the sub intermediate member 4 to consume the energy (the state of c in FIG. 1). The arc generated between the intermediate member 4 and the input contact 1 and the output contact 2 can also be made very small or hardly generated.

  In the first embodiment, as shown in FIG. 2, the main intermediate member 3 is driven to be opened and closed by the main drive means 51, and the sub intermediate member 4 is driven to be opened and closed by the sub drive means 52. The main drive unit 51 and the sub drive unit 52 are controlled by the control unit 6 so as to open and close individually.

  The main drive unit 51 and the sub drive unit 52 are each formed by a solenoid. Then, the timing for driving the main driving means 51 and the sub driving means 52 by the control means 6 is shifted as shown in FIG.

  Specifically, the control means 6 controls the main drive means 51 to be driven first, and then the sub drive means 52 is driven after a predetermined time has elapsed. The opening / closing drive timing of the main drive unit 51 and the sub drive unit 52 can be set by using an RC circuit having a resistor R and a capacitor C, or by using a timer.

  In the present embodiment, as shown in FIG. 2, a current detector 61 is provided at the input contact 1 to detect a current amount immediately before interruption, and to output the detected current amount to the control means 6. . The control means 6 controls so as to determine the timing for opening the sub-side drive means 52 in accordance with the detected current amount.

  In the first embodiment, since the two driving units are individually driven, it is possible to finely set the timing of the opening / closing drive of each. Further, the timing can be adjusted according to the current value. Thus, by providing the main drive means 51 and the sub drive means 52, the breaking performance of the relay can be further improved.

  Further, in the first embodiment, a plate-shaped permanent member is provided between the input contact 1 and the main intermediate member 3, between the contact portions 31 and 32 of the main intermediate member 3, and between the main intermediate member 3 and the output contact 2. It has a magnet 7.

  Further, as shown in FIG. 1, the permanent magnets 7 are arranged on the same straight line such that one pole (for example, N pole) is located on the same side. These permanent magnets 7 apply a magnetic field between the input contact 1 and the main intermediate member 3 and between the output contact 2 and the main intermediate member 3. When the main intermediate member 3 is separated from the input contact 1 and the output contact 2 by the magnetic field of the permanent magnet 7, the arc generated between the contacts is elongated and distorted by the Lorentz force.

  In this embodiment, when the relay is energized, a current flows from the input contact 1 and a current flows in series to the main intermediate member 3 and the output contact 2. In the state shown in FIG. 1, the permanent magnets 7 are arranged such that the lines of magnetic force are directed from left to right. Therefore, according to Fleming's left-hand rule, the forward force and the backward force are generated alternately in the Lorentz force in FIG. 1, and the arc generated at the time of contact breaking is alternately distorted back and forth.

  When the main intermediate member 3 is separated from the input contact 1 and the output contact 2, even if an arc is generated between the contacts, the arc is distorted in the above-described direction by the magnetic field of the permanent magnet 7, so that the arc is extinguished. Can be performed more quickly, and high-speed cutoff can be performed.

  In addition, since the direction of arc extension is alternately different along the direction of contact arrangement, even if a reverse current such as regenerative energy is generated, the arcs will not be connected to each other, and high-speed interruption of the reverse current is possible. It becomes.

(Test Example 1)
For the DC relay shown in the first embodiment, the production using two types of Ag alloys of the first layer and the second layer shown in the `` Chemical composition '' column shown in Table 1 on the contact surface of each contact portion did.

  For these Ag alloys, first, Ag alloys having two kinds of chemical compositions of a first layer and a second layer were melted and cast to produce ingots. After rough processing each of them, the first layer and the second layer ingot were overlapped, and hot-pressed with a hot roll at 850 ° C. in an argon atmosphere to produce a composite material composed of two layers of Ag alloy.

  After pre-heating the obtained composite material under the same conditions as for hot pressing, a thin pure Ag plate is finally formed to a thickness of 1/10 of the entire thickness to the second layer on the side opposite to the first layer. The surface of the layer was hot pressed. Thereafter, the material was further cold-rolled into a hoop-shaped material, which was punched out to produce a composite contact chip having a width of 6 mm, a length of 8 mm and a thickness of 2.5 mm.

  The obtained chip was kept (internal oxidation) at 750 ° C. for 170 hours in an oxygen atmosphere at 4 atm (405.3 kPa) to obtain a composite contact specimen. The thickness of the first layer of the obtained specimen was as shown in Table 1, and the thickness of the Ag layer was approximately 1/10 of the thickness of each chip.

  The thickness of the first layer can be confirmed, for example, as follows using a cross-sectional specimen passing through the center of the contact and perpendicular to the surface. First, five starting points are set at equal intervals on the specimen surface near the surface in a direction parallel to the surface. Next, the hardness is confirmed from each point in the direction perpendicular to the surface (thickness) in the direction perpendicular to the surface at substantially equal intervals from the surface, and five hardness curves (line graphs) are created. Then, at a certain starting point, an intersection between the horizontal line having a hardness level of 190 and this curve is taken, and the horizontal distance from the surface to this intersection is defined as the thickness of the first layer at the starting point. Hereinafter, the thickness of the first layer at the starting points of the remaining four places is also taken, and the arithmetic average value of the obtained five data may be used as the thickness of the first layer. The thickness of the second layer can be measured similarly.

  At this time, an intersection with a horizontal line having a hardness level of 130 is taken, and the horizontal distance from the surface to this intersection may be set as the thickness of the second layer at a certain starting point. When an intermediate layer is provided, the horizontal distance between the intersection with the horizontal line having a hardness level of 190 and the intersection with the horizontal line having a hardness level of 130 may be the thickness of the intermediate layer at a certain starting point. In this test, the thickness of the first layer was measured by the above procedure.

  Samples in Table 1 marked with * are comparative examples. The amounts of the other components Sb, Ni, and Bi in Samples 11 to 18 were all 0.2% by mass. The chemical compositions of the first layer and the second layer of Samples 19 to 27 were the same, and the amounts of other components and Sb, Co, and Zn were 0.2% by mass in both layers. It is. The other components of Sample 28 and their amounts are 0.1 and 0.1 respectively for Sb, Pb, Ni, Bi, Co, and Zn in mass% units. The other components of Sample 29 and their amounts are 0.1 and 0.5 for Pb and 0.5 for Sb, Ni, Ca, Bi, Co, and Zn, respectively, in mass% units. The other components of Samples 30 to 32 and the amounts thereof are 0.2 in mass% for both Ni and Zn. In the chemical composition of the first layer and the second layer, the balance other than the components described in the table consists of Ag and unavoidable impurities.

  In Table 1, Samples 1 to 10 are sample groups in which the hardness of each layer was controlled by changing the amounts of Sn and In. Samples 11 to 18 are a sample group in which the amounts of Sn and In are changed and other components other than these are further added. Samples 19 to 27 are a group of samples in which the thickness of the first layer is changed.

In Samples 28 to 34, both the first layer and the second layer have the same chemical composition. In these, the hardness of the first layer was controlled as follows. First, in Samples 28 to 33, while increasing the cross-sectional area ratio of the first layer by 50% of that of the second layer, the same material was rolled at 450 ° C. for 30 minutes in a vacuum during the rolling of the first layer material. Annealing was performed, and further, after internal oxidation, shot blasting was performed on the surface of the first layer with alumina beads of # 120 at a projection pressure of 3 kgf / cm ² (294 kPa) for 3 minutes.

  Sample 34 was produced under the same conditions as the above samples except that the annealing temperature and time during the rolling were 750 ° C. and 5 hours, respectively. Although not shown in Table 1, in Samples 33 and 34, intermediate portions having a thickness of 190 μm and 230 μm were formed, respectively.

  Sample 35 was prepared by reducing the amount of oxides of Sn and In in the first layer as compared to the second layer, and lowering the hardness of the first layer than the hardness of the second layer, and is described in Table 1. After the Ag alloy of the first layer and the second layer having the chemical composition described above is melt-cast, hot-pressed and rolled, and then internally oxidized under the same conditions as described above.

  Sample 36 was prepared by melting and casting an Ag alloy of the first layer and the second layer having the chemical composition described in Table 1 and then, on a mating surface of the two layers, in a horizontal direction at a pitch of 1 mm and a width of 1 mm and a depth of 0.5. The concave and convex portions of mm are formed, the concave portions and the convex portions are hot-pressed in a state where the concave and convex portions are meshed with each other, then rolled, and then internally oxidized under the same conditions as described above.

  The thickness of the first layer of hardness of each sample prepared by the above method was confirmed by the above-described procedure. Table 1 shows the above results. Although not described in Table 1, the thickness of the intermediate portion of each of the samples other than Sample 33 and Sample 34 was less than 100 μm.

  Next, a composite contact chip was soldered to each of the contact portions 11, 12, 21, 22, 31, 32, 41, and 42 shown in FIG. 1 to form a contact surface.

  After that, it was fixed to two types of DC relays of a rated AC 30A frame and a 50A frame. Five such relays were prepared for each composite contact chip pair of each sample number. First, using all the assemblies of each sample, a rated current was supplied for 100 minutes, and the temperature at the time of this supply was measured to confirm the initial temperature characteristics.

  Next, under a 220V load condition, a breaking test was performed using a single assembly with a breaking current of 1.5kA for a 30A frame and a breaking current of 5kA for a 50A frame. confirmed.

  As for the temperature characteristics after the cutoff test, the rated current was continuously applied for 100 minutes, and the temperature at the time of the current supply was measured to confirm the temperature characteristics after the cutoff test.

  In the overload test, using the assembly whose initial temperature characteristics have been confirmed, switching is repeated 50 times at 5 second intervals with a current of 5 times the same rated current for both the 30 A frame and the 50 A frame, and The temperature characteristics after the overload test were confirmed by measuring the temperature during energization under the same conditions.

  The endurance test uses the assembly whose initial temperature characteristics have been confirmed, with the same rated current flowing through both the 30A frame and the 50A frame, and repeats opening and closing 6000 times at 5 second intervals, and then applying power under the same conditions as the initial confirmation above By measuring the temperature, the temperature characteristics after the durability test were confirmed.

  In the evaluation of these series of tests, the temperature characteristics were evaluated in five stages based on the results of the models of both the 30A and 50A frames, and the welding resistance was evaluated depending on whether or not welding was performed.

  The five-point evaluation of the temperature characteristics is as follows: 5 when the temperature rise during energization is 50 ° C or less; 4 when the temperature is over 50 ° C and 60 ° C or less; 3 when the temperature is over 60 ° C and 70 ° C or less; Was set to 1. These evaluations are shown in Table 2 corresponding to the sample numbers in Table 1. In Table 2, * is added to the sample number of the comparative example.

The following can be understood from the above results.
(1) For both the first and second layers, Sn is controlled within the range of 1 to 9% by mass, In is controlled within the range of 1 to 9% by mass, the micro Vickers hardness of the first layer is 190 or more, and the micro Vickers of the second layer is controlled. A relay using a contact having a hardness of 130 or less and a thickness of the first layer controlled within a range of 10 to 360 μm is within a range that is sufficiently practicable in the above comprehensive evaluation. On the other hand, a relay using a contact outside the above range has not reached a practical level in comprehensive evaluation.

  (2) The same can be said when a small amount of components such as Sb and Ni are contained in addition to Sn and In.

  (3) The hardness levels of the contact tips of Sample 1, Sample 10, Sample 18, Sample 31, Sample 32, Sample 35, and Sample 36, which are comparative examples, are outside the above range. However, in all cases, except for some characteristics, performance of a practical level could not be obtained comprehensively.

(Test Example 2)
Using the sample 24 of Table 1 of the first embodiment, a simulated relay having a contact pair was fabricated, boosted by a transformer, charged to a capacitor, and released with a thyristor to release the capacitance of the capacitor and open the relay contact. I adjusted the voltage and current when the contacts were opened while a large current flowed for a short time. The result is shown in FIG. At this time, even if a large current of 2600 A flowed, the contacts did not weld, and the voltage between the contacts increased rapidly and could be reliably shut off.

  In the graph of FIG. 4, when the cutoff voltage reaches 200 V, it is determined that the cutoff has been completed, and the power supply is stopped. Therefore, the voltage becomes zero when the power supply is stopped. From this, it is presumed that a relay using the above specific material as a contact material is excellent in welding resistance and can be cut off at high speed.

  In contrast, when a contact pair is formed using sample 27, when a large current of 1500 A flows as shown in FIG. 5, the contacts are instantaneously welded, the capacitor spontaneously discharges, and the It can be seen that the voltage behavior occurs only for 1 ms and fluctuates only by about 10 V.

(2nd Embodiment)
In the second embodiment, both intermediate members serve as intermediate contacts, and the electric resistance value of the sub intermediate member 4 is lower than that of the first embodiment.

  Although the electric resistance value of the sub intermediate member 4 is higher than the resistance value of the main intermediate member 3, when a current flows while both intermediate members are connected to the input contact 1 and the output contact 2, the sub intermediate member 4 There may be an electric resistance value at which a current flows (a low resistance value).

  In that case, as shown in FIG. 6, when the relay is energized, only the main intermediate member 3 is connected to the input contact 1 and the output contact 2, and the sub intermediate member 4 is separated from the input contact 1 and the output contact 2. deep.

  In this way, when the relay is energized, the sub intermediate member 4 is separated from the input contact 1 and the output contact 2 so that current can flow only through the main intermediate member 3.

  When the relay is cut off, the sub intermediate member 4 is connected to the input contact 1 and the output contact 2 immediately before the main intermediate member 3 is disconnected from the input contact 1 and the output contact 2. Then, after the main intermediate member 3 is separated from the input contact 1 and the output contact 2 and a predetermined time has elapsed, the sub intermediate member 4 is separated from the input contact 1 and the output contact 2.

  Also in this case, when the main intermediate member 3 is disconnected from the input contact 1 and the output contact 2, current flows through the sub intermediate member 4 and energy is consumed, and the energy of the arc is reduced.

(Third embodiment)
In the third embodiment, the two intermediate members 3 and 4 are movable contacts, and the intermediate members 3 and 4 are driven by one driving means 53 to open and close the main intermediate member 3 and the sub intermediate member 4 with a time difference. .

  In the third embodiment, as shown in FIG. 7, the input contact 1 and the output contact 2 are L-shaped fixed contacts. In FIG. 7, a main intermediate member 3 and a sub intermediate member 4 are provided below the input contact 1 and the output contact 2.

  The main intermediate member 3 has a U-shape, and the sub intermediate member 4 is disposed in the U-shaped central concave portion 33. The main intermediate member 3 and the sub intermediate member 4 are opened in the same direction. Specifically, the sub intermediate member 4 is interposed between the central recess 33 of the main intermediate member 3 and the input contact 1 and the output contact 2.

  The elastic member 53a and the connecting rod 53b are provided between the main intermediate member 3 and the sub intermediate member 4. The elastic member 53a is formed by a coil spring, and urges the sub intermediate member 4 toward the input contact 1 and the output contact 2.

  The connecting rod 53b is loosely inserted into the through hole 34 provided in the center portion of the sub intermediate member 4 and the coil spring 53a, one end is fixed to the sub intermediate member 4, and the other end is pulled out of the through hole 34. A stopper 53c is installed to prevent this. The length of the connecting rod 53b is such that the stopper 53c provided at the end does not abut on the main intermediate member 3 immediately after the coil spring 53a is fully extended.

  In the present embodiment, although not shown, the main intermediate member 3 is driven to open and close by a solenoid. The drive shaft 53d of the solenoid is fixed to the bottom of the main intermediate member 3. When the main intermediate member 3 is in contact with the input contact 1 and the output contact 2 and for a predetermined time from the start of the opening operation of the main intermediate member 3, the sub intermediate member 4 is brought into contact with the input contact by the biasing force of the coil spring 53a. 1 and output contact 2 are kept in contact.

  After a predetermined time has elapsed from the start of the opening operation of the main intermediate member 3, the coil spring 53a is fully extended, and the stopper 53c provided at the end of the connecting rod 53b abuts on the main intermediate member 3 by the opening operation of the main intermediate member 3 by the solenoid. . Then, the sub intermediate member 4 is separated from the input contact 1 and the output contact 2 in synchronization with the opening operation of the main intermediate member 3 via the connecting rod 53b.

  As described above, when the main intermediate member 3 is driven by the solenoid, the opening of the sub intermediate member 4 is performed a predetermined time after the opening operation of the main intermediate member 3 is started by the urging of the elastic member 53a and the connecting rod 53b. Be started.

  In the third embodiment, since the main intermediate member 3 and the sub intermediate member 4 can be driven by one driving unit, the driving unit can be downsized.

  Further, in the third embodiment, when the main intermediate member 3 is cut off from the input contact 1 and the output contact 2, even if an arc is generated between the respective contacts, a magnet for distorting the arc by a magnetic field is provided. Like that.

  In the third embodiment, two pairs of magnets 7 are provided in front and back in FIG. 7 near the contact portion of the main intermediate member 3, the input contact 1, and the output contact 2. In this case, the magnets 7 are arranged so that the lines of magnetic force extend from the back toward the front in FIG.

  In the third embodiment, the arc is distorted outward in the horizontal direction in FIG. 7 by the magnetic field of the magnet 7. Also in the third embodiment, the provision of the magnets 7 allows the arc to be interrupted more quickly.

(Fourth embodiment)
Further, FIG. 8 shows another embodiment (fourth embodiment) in which the main intermediate member 3 and the sub intermediate member 4 are driven to be opened and closed by one driving means as in the third embodiment.

  In the fourth embodiment, projections 54a and 54b projecting in a direction orthogonal to the opening and closing direction are attached to each of the main intermediate member 3 and the sub intermediate member 4. A solenoid is used as the driving means, and two engaging portions 54d and 54e are provided on the driving shaft 54c of the solenoid so as to contact the projections 54a and 54b in a stepwise manner and press the projections.

  Then, after the engaging portion 54d is engaged with the projection 54a of the main intermediate member 3 to open the main intermediate member 3, the other engaging portion 54e is engaged with the projection 54b of the sub The intermediate member 4 is opened.

  At this time, the main intermediate member 3 and the sub intermediate member 4 are constantly urged in the closing direction in the opening and closing direction by the coil spring 54f, and perform the opening operation of the solenoid against the urging of the coil spring 54f. As described above, also in the fourth embodiment, the main intermediate member 3 and the sub intermediate member 4 can be driven to open and close with a time difference by one driving unit.

(Fifth embodiment)
Further, in the fifth embodiment shown in FIG. 9, the input contact 1 can be connected to the intermediate members 3 and 4 via the input side connection contact 81, and the output contact 2 can be connected to the intermediate members 3 and 4 via the output side connection contact 82. Connectable to 4. In addition, the main intermediate member 3 is an intermediate contact that is electrically connected to or disconnected from the input side connection contact 81 and the output side connection contact 82.

  The input contact 1 and the output contact 2 have a columnar shape. Further, the input-side connecting contact 81 and the output-side connecting contact 82 have a long flat plate shape. The main intermediate member 3 has a U-shape. The sub intermediate member 4 is fixed between the input side connection contact 81 and the output side connection contact 82.

  In the fifth embodiment, the input contact 1, the output contact 2, and the main intermediate member 3 are provided so as to sandwich the input-side connection contact 81 and the output-side connection contact 82. Further, in the fifth embodiment, the sub intermediate member 4, the input side connection contact 81, and the output side connection contact 82 are fixed contacts, and the input contact 1, the output contact 2, and the main intermediate member 3 are movable contacts.

  The input contact 1 and the output contact 2 open in the same direction (upward in FIG. 9), and the main intermediate member 3 opens in the opposite direction (downward in FIG. 9). In the fifth embodiment, the electric resistance value of the sub intermediate member 4 is set to a high resistance value.

  When the relay is energized, the main intermediate member 3 and the sub intermediate member 4 are connected to the input contact 1 and the output contact 2 via the input side connection contact 81 and the output side connection contact 82. At this time, since the sub intermediate member 4 has a high resistance value, no current flows through the sub intermediate member 4 and current flows only through the main intermediate member 3.

  When the relay is cut off, first, the main intermediate member 3 is disconnected from the input side connection contact 81 and the output side connection contact 82. At this time, a current also flows through the sub intermediate member 4, and the energy of the current is consumed by the resistance of the sub intermediate member 4, and a current is generated between the main intermediate member 3 and the input side connection contact 81 and the output side connection contact 82. The generated arc can be reduced or prevented from occurring.

  After a lapse of a predetermined time, the input contact 1 is disconnected from the input side connection contact 81, and the output contact 2 is disconnected from the output side connection contact 82. Also at this time, since the energy of the current is consumed by the sub-intermediate member 4, almost no arc is generated between the input contact 1 and the input-side connection contact 81 and between the output contact 2 and the output-side connection contact 82. Can be prevented from occurring.

(Sixth embodiment)
Further, the sixth embodiment also has a configuration including an input contact 1, an input side connection contact 81, an output contact 2, an output side connection contact 82, a main intermediate member 3, and a sub intermediate member 4, as shown in FIG. In the sixth embodiment, the input contact 1, the main intermediate member 3 serving as an intermediate contact, and the output contact 2 are movable contacts, and the sub intermediate member 4, the input side connection contact 81, and the output side connection contact 82 are fixed contacts.

  In the sixth embodiment, the input contact 1, the output contact 2, and the main intermediate member 3 are arranged on the same side with respect to the input side connection contact 81 and the output side connection contact 82, and are opened in the same direction. Then, the sub intermediate member 4 is fixed to the connection contacts 81 so as to connect the input connection contacts 81 and the output connection contacts 82.

  When the relay is energized, the main intermediate member 3 and the sub intermediate member 4 are connected to the input contact 1 and the output contact 2 via the input side connection contact 81 and the output side connection contact 82. At this time, since the sub intermediate member 4 has a high resistance value, no current flows through the sub intermediate member 4 and current flows only through the main intermediate member 3.

  When the relay is cut off, the input contact 1, the main intermediate member 3, and the output contact 2 are simultaneously disconnected from the input-side connecting contact 81 and the output-side connecting contact 82 at the same time. When the relay is cut off, current flows through the sub-intermediate member 4, so that almost no arc is generated between the main intermediate member 3 and the input-side connection contacts 81 and the output-side connection contacts 82. The arc generated between the side connection contact 81 can be made smaller, and the arc generated between the output contact 2 and the output side connection contact 82 can be made smaller than the input contact 1 side.

  According to the sixth embodiment, the input contacts and the like are required to have arc resistance as compared with the first to fifth embodiments, but the input contact 1, the output contact 2, and the main intermediate member 3 are driven at once. Since the relay can be shut off, the configuration of the relay can be simplified.

  In this case, the input contact 1, the output contact 2, and the main intermediate member 3 may be fixed contacts, and the input-side connection contact 81, the output-side connection contact 82, and the sub-intermediate member 4 may be formed as a movable contact as one member. it can. If the sub intermediate member 4 is a movable contact, the configuration of the relay can be further simplified.

  Further, in the sixth embodiment, the same permanent magnets 7 as those in the first embodiment are provided. In the sixth embodiment as well, the arc is distorted in the same direction as the first embodiment, and even if a reverse current flows, no arc interference occurs, and the arc can be extinguished more quickly.

(Seventh embodiment)
Further, the seventh embodiment of FIG. 11 has an input contact 1, an input side connection contact 81, an output contact 2, an output side connection contact 82, a main intermediate member 3, and a sub intermediate member 4, and the input contact 1 and the main intermediate In a case where the member 3 and the output contact 2 are simultaneously separated from each connection contact, the electric resistance of the sub intermediate member 4 is high.

  In the seventh embodiment, the input contact 1, the main intermediate member 3 serving as an intermediate contact, and the output contact 2 are fixed contacts, and the sub intermediate member 4, the input-side connecting contact 81, and the output-side connecting contact 82 are movable contacts.

  In the seventh embodiment, steps 81a and 82a to which the sub-intermediate member 4 is fitted are formed on the side of the input-side connection contact 81 and the output-side connection contact 82 facing the main intermediate member 3. The sub intermediate member 4 is arranged so as to be surrounded by the steps 81a and 82a and the main intermediate member 3, and the tip of the drive shaft 55 of the solenoid is fixed to the center of the sub intermediate member 4.

  In the seventh embodiment, when the relay is energized, the sub intermediate member 4 is kept in a non-contact state with the main intermediate member 3, the input side connection contact 81, and the output side connection contact 82 by the drive shaft 55 of the solenoid. . That is, the sub intermediate member 4 is separated from the input side connection contact 81 and the output side connection contact 82. By doing so, it is possible to prevent a current from flowing through the sub intermediate member 4 during energization.

  Further, the drive shaft 55 is driven to connect the sub intermediate member 4 to the input-side connection contact 81 and the output-side connection contact 82 a predetermined time before the start of the relay breaking operation. That is, when starting to cut off the relay, the drive shaft 55 of the solenoid is driven in the opening direction, and first, the sub intermediate member 4 is brought into contact with the step portions 81a, 82a of the input side connection contact 81 and the output side connection contact 82. . Due to the contact of the sub intermediate member 4 with each connection contact, a current flows from the input contact 1 to the output contact 2 via the sub intermediate member 4, and energy is consumed.

  Next, after a lapse of a predetermined time from the connection of the sub intermediate member 4 to each connection contact, the input side connection contact 81 is separated from the input contact 1 while the sub intermediate member 4 is connected to these connection contacts, and the output side connection The contact 82 is separated from the output contact 2.

  That is, by further driving the drive shaft 55 of the solenoid in the opening direction, the input side connection contact 81 and the output side connection contact 82 are pushed by the sub intermediate member 4 to move in the opening direction, and the input side connection contact 81 and the output The side connection contact 82 is simultaneously disconnected from the input contact 1, the output contact 2, and the main intermediate member 3.

  At this time, the current that flows through the sub intermediate member 4 and consumes energy is cut off, so that the arc generated between the contacts can be reduced. In the seventh embodiment, the input-side connection contact 81 and the output-side connection contact 82 can also be opened and closed by a driving unit (solenoid) for driving the sub intermediate member 4.

  It should be noted that, among the embodiments described above, even in the embodiment without a magnet, when the main intermediate member is cut off with respect to the input contact and the output contact, a magnet for distorting an arc generated between the contacts by a magnetic field is provided. Can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram illustrating a first embodiment of a relay of the present invention, showing a stepwise state when the relay is cut off from a state when the relay is energized. FIG. 4 is an explanatory diagram showing a relationship between a driving unit for opening and closing each intermediate member of the first embodiment and a control unit. FIG. 5 is an explanatory diagram showing a timing of an opening operation of each drive unit of the first embodiment. 6 is a graph showing the behavior of voltage and current at the time of interruption in a relay using the contact material of Sample 24 in Table 1. 6 is a graph showing the behavior of voltage and current at the time of interruption in a relay using the contact material of Sample 27 in Table 1. It is a schematic structure figure of a relay showing a 2nd embodiment of the present invention relay. FIG. 9 is a schematic configuration diagram illustrating a third embodiment of the relay of the present invention, showing a stepwise state when the relay is cut off from a state when the relay is energized. It is a schematic structure figure showing a 4th embodiment of the present invention relay, and is a longitudinal section of a relay. It is a schematic structure figure showing a 5th embodiment of the present invention relay, and shows a state when a relay is cut off from a state at the time of energization of a relay step by step. It is a schematic structure figure showing a 6th embodiment of the present invention relay, and shows a state at the time of shutting off a relay from a state at the time of energization of a relay. It is a schematic structure figure of a relay showing a 7th embodiment of the present invention relay.

Explanation of reference numerals

1 input contact 2 output contact 3 main intermediate member
33 recess 34 through hole 4 sub intermediate member
51 Main drive unit 52 Sub drive unit 53 Drive unit
53a Elastic member 53b Connecting rod 53c Stopper 53d Drive shaft
54a, 54b Projection 54c Drive shaft 54d, 54e Engagement part 54f Coil spring
55 Drive shaft 6 Control means 61 Current detector 7 Permanent magnet 81 Input side connection contact 82 Output side connection contact

Claims (13)

An input contact, an output contact, and an intermediate member capable of connecting the two contacts,
The intermediate member is
A main intermediate member for flowing current from the input contact to the output contact when the relay is energized;
When the main intermediate member is separated from the input contact and the output contact, a sub intermediate member that allows current to flow from the input contact to the output contact,
A DC relay, wherein the electric resistance value of the sub intermediate member is larger than the electric resistance value of the main intermediate member. The main intermediate member and the sub intermediate member are intermediate contacts that are electrically connected or disconnected from the input contact and the output contact,
When energizing the relay, connect the main intermediate member and the sub intermediate member to the input and output contacts,
2. The DC relay according to claim 1, wherein when the relay is cut off, the sub intermediate member is separated from the input contact and the output contact after the main intermediate member is separated from the input contact and the output contact.   3. The DC relay according to claim 2, further comprising: a main-side driving unit that opens and closes the main intermediate member; and a sub-side driving unit that opens and closes the sub-intermediate member.   4. The DC relay according to claim 3, further comprising control means for detecting a current amount of the DC relay and opening the sub intermediate member by the sub-side driving means in accordance with the detected current amount.   3. The DC relay according to claim 2, further comprising a driving unit that drives the main intermediate member and the sub intermediate member to open and close with a time difference. The driving means is
An elastic member and a connecting rod disposed between the main intermediate member and the sub intermediate member, with the sub intermediate member interposed between a part of the main intermediate member and the input contact and the output contact,
The elastic member biases the sub intermediate member toward the input contact and the output contact,
The connecting rod has one end fixed to the sub intermediate member, and the other end connected to the main intermediate member so that the sub intermediate member can move relative to the main intermediate member,
By the opening and closing drive of the main intermediate member, when the main intermediate member is in contact with the input contact and the output contact, and during a predetermined time from the start of the opening operation of the main intermediate member, the sub intermediate member is input by the biasing force of the elastic member. Contacts the contacts and output contacts,
After a lapse of a predetermined time from the start of the opening operation of the main intermediate member, the sub intermediate member is separated from the input contact and the output contact in synchronization with the operation of the main intermediate member via the connecting rod. Item 6. The DC relay according to Item 5. The input contact is connectable to the intermediate member via the input side connection contact, the output contact is connectable to the intermediate member via the output side connection contact, and the main intermediate member is electrically connected to the input side connection contact and the output side connection contact. As an intermediate contact to be interrupted,
When the relay is energized, the main intermediate member and the sub intermediate member are connected to the input contact and the output contact via the input side connection contact and the output side connection contact,
When the relay is cut off, after the input side connection contact and the output side connection contact are separated from the main intermediate member, the input contact and the input side connection contact, and the output contact and the output side connection contact are separated. The DC relay according to claim 1. The input contact is connectable to the intermediate member via the input side connection contact, the output contact is connectable to the intermediate member via the output side connection contact, and the main intermediate member is electrically connected to the input side connection contact and the output side connection contact. As an intermediate contact to be interrupted,
When the relay is energized, the main intermediate member and the sub intermediate member are connected to the input contact and the output contact via the input side connection contact and the output side connection contact, and when the relay is cut off, the main intermediate member, the input contact, the output The direct current relay according to claim 1, wherein the contact, the input side connection contact, and the output side connection contact are all disconnected simultaneously.   9. The DC relay according to claim 7, wherein the sub intermediate member is fixed to the input side connection contact and the output side connection contact. When energizing the relay, separate the sub intermediate member from the input side connection contact and the output side connection contact,
9. The DC relay according to claim 8, wherein the sub-intermediate member is connected to the input-side connecting contact and the output-side connecting contact a predetermined time before the start of the relay breaking operation.   The DC relay according to claim 10, further comprising a driving unit that opens and closes the input-side connection contact and the output-side connection contact in conjunction with the driving of the sub intermediate member.   The magnet according to any one of claims 1 to 11, further comprising a magnet for distorting an arc generated between the contacts by a magnetic field when the main intermediate member is disconnected from the input contact and the output contact. DC relay as described.   The contact portion of the contact, the contact portion of the main intermediate member with the contact, and the contact portion of the sub intermediate member with the contact are made of an Ag alloy having a chemical composition containing 1 to 9% by mass of Sn and 1 to 9% by mass of In. Has a first layer of the surface portion and a second layer of the inside, the micro Vickers hardness of the first layer is 190 or more, the micro Vickers hardness of the second layer is 130 or less, the thickness of the first layer, The DC relay according to any one of claims 1 to 12, wherein the DC relay is in a range of 10 to 360 µm.

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