CN107818891B - Switchgear with means for reliably indicating the switch position when the contacts are welded - Google Patents

Abstract

The invention relates to a switching device having a device for reliably indicating the position of a switch when a contact is welded, comprising: an operating mechanism which has an operating element and is connected to a locking mechanism (11) via a first transmission mechanism, which moves a drive slide (15) via a second transmission mechanism; and a contact arrangement having a fixedly positioned contact carrier with contacts, which is opposite a movable contact carrier with contacts, which is guided in a contact slide, the invention is characterized in that the device for reliably indicating the switching position when the contacts are welded is formed in the interior of the second gear mechanism in the form of a bevel gear section (12), wherein the bevel gear section (12) is in operative connection with the drive slide (15) and has two differently formed locking devices.

Description

Switchgear with means for reliably indicating the switch position when the contacts are welded

technical field

The invention relates to a switchgear with a device for reliable switching position indication when the contacts are welded, which has an operating mechanism, which has an operating element and is connected via a first transmission mechanism and a locking mechanism In the connected state, the locking mechanism moves the drive slide via the second transmission mechanism and also has a contact arrangement with a fixedly positioned contact carrier with contacts, which is connected to a movable contact carrier. , The contact carrier with the contacts is opposite, this movable contact carrier is guided in the contact slide.

Background technique

Switchgear, in particular circuit breakers, are mainly used for safe switching off in the event of a short circuit and thus protect consumers. Furthermore, the electrical or mechanical switching unit is suitable for manually switching consumers depending on the operating state and for safely isolating the installation from the network during maintenance work or when changes are made to the installation. Electrical switching units generally operate electromagnetically.

That is, switching units of this type are high-tech, electrical switching devices with integrated protection for motors, conductors, transformers and generators. In everyday life they are used in functional parts with lower switching frequencies. Such switching units are suitable for overload protection in addition to short-circuit protection.

In the event of a short circuit, the electrical switching unit safely switches off the electrical equipment. It thus provides safety protection against overloading. Every conductor through which current flows heats up more or less violently. This heating depends here on the ratio of the current intensity to the cross-section of the current conductor, the so-called current density. The current density should not be too high, as otherwise the conductor insulation may be scorched by excessive heat generation or a fire may occur. To protect electrical equipment from damaging influences, switching units are used as overcurrent protection devices.

The circuit breaker has two separate triggering mechanisms for overload protection and short-circuit protection. The two triggers are connected in series. Protection in the event of a short circuit is performed by electrical triggers which act almost immediately in time. In the event of a short circuit, the electromagnetic trigger immediately opens the blocking mechanism of the circuit breaker. The switching anchors separate the switching elements before the short-circuit current can reach its maximum value.

The known switch unit has a contact slide unit with a contact slide and a movable switching element. Furthermore, the movable switching element has electrical contacts. Furthermore, this type of switching unit also has a first contact with the current line. In the switched-on state, the electrical contacts of the movable switching element contact the stationary contacts of the switching unit. In a short-circuit condition, the electrical contacts of the movable switching element are released from the fixed contacts, thereby interrupting the current flow. Here, the movable switching element is released from the fixed contact.

In addition to fulfilling their protective function as overload and short-circuit triggers, circuit breakers, as already mentioned above, are also responsible for switching off and on the motor properly. To demonstrate these functions, the circuit breaker must be capable of switching ten times the rated motor current according to the product standard. In order to be able to ensure this limit load, the circuit breaker must perform a double interruption of the three current paths, each with a movable bridge and two movable bridges, almost simultaneously and in the jump function. exists in the form of a contact site and two fixed contact sites.

In order to achieve this function, the contact assembly consisting of the contact slide and the movable bridge is opened in the form of an operating element, a locking mechanism and an operating chain via a manually operated mechanical device. This switch-on is accomplished by a so-called fast switch-on. Here, the three-contact system is opened by a mechanical device only after the locking mechanism has been switched on. The spring store now determines the movement of the contact system when it is switched on in the form of a contact load spring.

After the bridge has hit the stationary switching element, the contact slide is accelerated until it bounces off the stop. Re-opening of the contact system is caused by the rebound of the contact slide and the resulting kinetic energy. This can lead to fusion welding if the current in the current path is raised at the same time.

In order to prevent the contact slide from rebounding at the switch lever after the contact has been closed, and thus allowing the contact to open again, a blocking spring is used around the contact slide, in the form of a leaf spring, which brakes the contact Movement of the slider. However, in order for the blocking spring to function properly, a pre-extension of the switching rod must be extended between the switching rod and the contact slide. However, due to the extension of the switch lever pre-extension, the function "position display of the main contacts in the case of welding of the contacts in a device with a separation function", which is required in such a switchgear, may result It cannot be achieved in a conventional way. This function means that the operating element in the form of a toggle lever can no longer return to the open position when the contacts are welded.

So far, the lowest maximum device measurement value, ie the nominal current to be conducted, should be chosen so that the switch as described above does not need to be turned on. The closing dynamics of the contact assembly consisting of the contact slide and the movable bridge therefore do not have to approximate the step function as precisely as it is now, to ensure that ten times the rated motor current can be switched on. The use of blocking springs is therefore also not necessary, and is also possible with a small pre-extension between the switch lever and the contact slide. This leads to the use of a simpler system in which a part of the bevel gear connection, the so-called bevel gear segment, enters when it is rotated into the off position if its downward movement is hindered by the welded contacts in the connecting piece of the drive slider. This is derived from FIG. 1 by a system known in the prior art.

FIG. 1 shows a locking mechanism 1 of a switchgear, in particular a circuit breaker, with a rotatably mounted bevel gear section 2 which is operatively connected to a drive slide 3 . The drive slider 3 is in an effective connection state with the switch lever 4, and the switch lever is in an effective connection state with the contact device. The movable contact carrier 7 of the contact 8 is formed, which is guided in the contact slide. A web 10 is arranged on the drive slide 3 . When the drive slide 3 is prevented from moving downward by the welded contacts 6 , 8 , the bevel gear section 2 moves into the web 10 when it is rotated into the off position. Due to the web 10 on the drive slide 3 , the bevel gear section 2 cannot conduct further, so that the actuating element in the form of a toggle lever on the cover cannot be transferred into its off position. Accordingly, the position of the main contacts has not been indicated so far in switchgears with a separating function and welded contacts.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to realize a switchgear having means for reliably displaying the switch position when the contacts are welded.

According to the invention, this object is solved by a switchgear with a device for reliably indicating the switch position when the contacts are welded, the device having an operating mechanism and a contact arrangement, the operating mechanism having an operating element and via a first The transmission mechanism is in effective connection with the blocking mechanism, the blocking mechanism moves the driving slider through the second transmission mechanism, and the contact device has a fixedly positioned contact carrier with contacts, and the contact carrier is connected to a movable contact carrier with contacts. The contact carriers lie opposite each other, the movable contact carriers being guided in the contact slide. In this case, the invention is characterized in that the means for reliably indicating the switching position when the contacts are welded are formed in the form of a bevel gear section inside the second transmission, wherein the bevel gear section is It is operatively connected to the drive slide and has two locking devices of different configurations.

For high rated currents (IN _100A ) and the following, determined by standardization, that must be able to switch on 13.5 times the rated current of the motor, the switch-on dynamics need to be as close as possible to the "step function". This is achieved by fast switching on.

In order to avoid that the contact slide is further accelerated due to this rapid switch-on due to inherent inertia, bounces at the switch lever, and the bridge opens again due to the impulse, a blocking spring is used, which brakes the movement of the contact slide. However, contact springs require a certain working path to operate. The working path is generally greater than 2.3mm. This working path is the extension between the switch lever and the contact slide. However, raising by pre-extension (Vorlauf) can no longer make the old system work properly, because the drive slider may move down too much path even if the contacts are welded. The bevel gear section is also no longer braked by the web of the drive slide when it rotates, and the upper toggle lever can therefore be shifted into the closed position.

The system according to the invention now shows a unique configuration, whereby a greater pre-extension between the switch lever and the contact slide can be achieved. During normal shutdown, the bevel gear cannot be braked or locked. If the switch is normally closed, the bevel gear section moves in a clockwise direction and the drive slide moves downward as the contacts are opened. As a result, the catch projection of the drive slide slides into the recess provided for it below the bevel gear section, and thus the upper connected toggle lever can also be moved into the closed position.

When the contacts are welded, the bevel gear section must be locked so that the toggle lever on the cover cannot move into its closed position. During the switch-off process with welded contacts, the bevel gear segment is first also moved in the clockwise direction. However, since the drive slide cannot be moved downward due to the welded contacts, the drive slide does not slide into its predetermined recess, but remains on the flat area of the bevel gear section. As a result, the locking contour of the bevel gear section and the locking contour of the drive slide block each other, and as a result, the bevel gear section and the toggle lever can no longer be moved into the off position.

Due to the special shape of the bevel gear section in combination with the catch projections of the drive slide, it is possible to release the bevel gear section or lock the bevel gear section, depending on whether the contacts are welded or freely movable. Whether the movement of the bevel gear is blocked depends on whether and how long the drive slide can be moved down. In the prior art, the space here is very small, so that only a small pre-extension can be achieved between the switch lever and the contact slide. These pre-extensions are less than 1.5mm. This new configuration is less reliant on pre-extension between the switch lever and the contact slide. A pre-extension of up to 2.6 mm can be achieved here, which is essential for the use of the blocking spring.

A particular advantage of the present invention is that there is no need to deviate from the usual installation procedure, as the components to be installed remain the same as in older systems. Just the functionality has been changed and improved. In addition, the new locking mechanism is more stable. This makes it easy also to pass the standardized test in which the toggle lever is loaded with the maximum torque with the contacts welded.

According to a propulsion solution of the design concept of the present invention, it can be provided that the drive slide is in an active connection state with the bevel gear section via the catch projection.

According to a specific embodiment of the inventive concept, it can be provided that a first locking device is formed in the bevel gear section, which is present in the form of a cutout which is geometrically adapted to the drive slide. The block captures the raised profile.

An advantageous configuration of the design concept according to the invention can consist in that the bevel gear section has a second locking device in the form of a blocking surface and a locking contour.

An advantageous configuration of the design concept according to the invention can consist in that, when the contacts are welded, the second locking device of the bevel gear section is in an operative connection with the catch projection of the drive slide.

A specific configuration of the design concept according to the invention can be that, when the bevel gear segment rotates in the clockwise direction, the catch projection of the drive slide can be removed from the bevel gear segment without welding the contacts. The second locking device bypasses and engages the first locking device for the switched-on state of the switching device.

A refinement of the design concept according to the invention can consist in that the switchgear is a circuit breaker.

The switching device according to the invention has an operating element to be manually actuated, which is operatively connected to the counter gear. This is the first transmission mechanism. The mating gear and the bevel gear segment are effectively connected. The bevel gear section is rotatably arranged between preferably two plates oriented parallel to each other. The bevel gear section is in an effective connection with the drive slide. This is the second transmission mechanism. The drive slide has two end regions. The first end region of the drive slide is in operative connection with the bevel gear section and is configured to capture the projection. The catch projections are formed as protrusions and as flat areas preferably formed at an angle of 90° therewith.

A first locking device is formed in the section of the bevel gear, which is present in the form of a cutout which is geometrically adapted to the contour of the catch projection of the drive slide. The cutout has a preferably nose-shaped receptacle for the projection of the catch projection of the drive slide and a flat area, preferably formed at an angle of 90° therewith, on which abutment rests. The flat area of the capture protrusion of the drive slider. In the switched-on state of the switching device, the projection of the catch projection of the drive slide abuts against the flat region of the cutout of the bevel gear section. When the switchgear is normally open, the bevel gear section rotates in a clockwise direction. In this case, the catch projection formed by the projection of the drive slide and the flat area slides into the cutout of the bevel gear section, wherein the projection engages in the cutout in the first end area of the drive slide in the receptacle of the part, and the plane area of the bevel gear section and the plane area of the drive slide abut against each other.

The switchgear also has a contact arrangement with a fixedly positioned contact carrier with contacts, which is arranged opposite the movable contact carrier with contacts and is movable The contact carrier is guided in the contact slide. The second end region of the drive slide is operatively connected to the contact arrangement. During normal disconnection, the drive slide moves generally downwards and opens the contacts.

When the contacts are welded, the bevel gear section must be locked so that the toggle lever on the cover cannot move into its off position. During the switch-off process with welded contacts, the bevel gear segment is first also moved in the clockwise direction. However, since the drive slide cannot be moved downward due to the welded contacts, the drive slide does not slide into its predetermined recess, but remains on the flat area of the bevel gear section. Furthermore, the locking contour of the bevel gear section engages with the plane area of the drive slide in the vicinity of the flat area of the bevel gear section. As a result, the bevel gear section and the toggle lever can no longer be moved into the switched-off position.

Description of drawings

Further embodiments and advantages of the invention are explained below with the aid of examples and with the aid of the figures.

The figure schematically shows:

FIG. 1 shows, in a perspective view, a switchgear known from the prior art in an off state with a locking mechanism;

FIG. 2 shows a switchgear according to the invention in the switched-on state with a locking mechanism in a plan view;

FIG. 3 shows a top view of the locking mechanism according to FIG. 2 , which is in a rotational movement and in the normal switched-off state;

Fig. 4 shows the latching mechanism according to Figs. 2 and 3, just before reaching the off state;

FIG. 5 shows, in a plan view, the locking mechanism according to FIG. 2 in the open state when the contacts are welded.

Detailed ways

FIG. 1 shows a locking mechanism 1 of a switchgear, in particular a circuit breaker, known from the prior art. The locking mechanism 1 has a rotatably mounted bevel gear section 2 which is operatively connected to the drive slide 3 . The drive slider 3 is in an effective connection state with the switch lever 4, and the switch lever is in an effective connection state with the contact device. The movable contact carrier 7 of the contacts 8 is guided in the contact slide. Latches 10 are arranged on the drive slide 3 . When the downward movement of the drive slide 3 is prevented by the welded contacts 6 , 8 , the bevel gear section 2 moves into the web 10 when it is rotated into the closed position. Due to the web 10 on the drive slide 3, the bevel gear section 2 cannot be conducted further, so that the operating element in the form of a toggle lever on the cover cannot be transferred into its off position. Accordingly, the position of the main contacts has not been indicated so far in switchgears with a separating function and welded contacts.

FIG. 2 shows a switchgear according to the invention with a locking mechanism 11 . The locking mechanism 11 has a bevel gear section 12 which is rotatably arranged between two plates 13 , 14 which are preferably arranged parallel to each other. The bevel gear section 12 is operatively connected to the drive slide 15 . This mechanism is the second transmission mechanism. The drive slide 15 has end regions 16 , 17 . The first end region 16 of the drive slide 15 is operatively connected to the bevel gear section 12 and is configured to catch the projection 18 . The catch projection 18 is formed as a projection 19 and a flat area 20 which is preferably formed at an angle of 90° to the projection. A first locking device is formed in the bevel gear section 12 and is present in the form of a cutout 21 which is geometrically adapted to the outer shape of the catch projection 18 of the drive slide 15 . The cutout 21 has a preferably nose-shaped receptacle 22 for driving the projection 19 of the catch projection 18 of the slide 15 and a flat area 23 preferably formed at an angle of 90° therewith. The plane area 20 of the catch projection 18 of the drive slide 15 rests at the plane area 23 . In the switched-on state of the switching device, the projection 19 of the catch projection 18 of the drive slide 15 abuts against the flat area 23 of the cutout 21 of the bevel gear section 12 . When the switchgear is normally opened, the bevel gear section 12 rotates in a clockwise direction. In this case, the catch projection 18 formed by the projection 19 of the drive slide 15 and the flat area 20 slides into the cutout 21 of the bevel gear section 12 , wherein in the first end area 16 of the drive slide 15 The projections 19 at the top engage into the receptacles 22 of the recesses 21 , and the flat area 20 of the bevel gear section 12 and the 23 of the drive slide 15 abut against each other. The drive slide 15 is generally moved downwards and opens the contacts.

Figure 3 shows the locking mechanism according to the invention in a first movement for normal closing. When the switchgear is normally switched off, the bevel gear section 12 rotates in a clockwise direction. At this point, the catch projection 18 formed by the projection 19 of the drive slide 15 and the flat area 20 slides into the cutout 21 of the bevel gear section 12 , wherein the catch in the end area 16 of the drive slide 15 slides into the recess 21 of the bevel gear section 12 . The projections 19 are introduced into the receptacles 22 of the recesses 21 .

FIG. 4 shows the locking mechanism according to the invention just before reaching the end point in the switched-off state. In this switching position, the projections 19 of the catch projections 18 of the drive slide 15 engage in the receptacles 22 of the recesses 21 of the bevel gear section 12 . Furthermore, the flat area 23 of the cutout 21 of the bevel gear section 12 almost rests on the flat area 20 of the catch projection 18 of the drive slide 15 .

Figure 5 shows the latching mechanism according to the invention with the contacts welded. When the contacts are welded, the bevel gear section 12 must be locked. During the switch-off process with welded contacts, the bevel gear section 12 is first also moved in a clockwise direction. However, since the drive slide 15 cannot move downward due to the welded contacts, the drive slide does not slide into its predetermined recess 21 but is locked by the flat area of the bevel gear section 12 . Furthermore, the locking contour 24 of the bevel gear section 12 arranged in the end region of the flat region 23 and the flat region 20 of the catch projection 18 of the drive slide 15 engage with each other. As a result, the bevel gear section 12 and the toggle lever can no longer be moved into the off position.

The switchgear according to the invention with means for reliably indicating the position of the switch in the event that the contacts are welded is characterized in that it is not necessary to deviate from the usual installation procedure, since the components to be installed remain the same as in older systems. Just the functionality has been changed and improved. In addition, the new locking mechanism is more stable. This makes it easy also to pass the standardized test in which the toggle lever is loaded with the maximum torque with the contacts welded.

List of reference signs

1 locking mechanism

2 bevel gear sections

3 Drive slider

4 switch lever

5 Fixed-position contact carrier

6 contacts

7 Movable contact carrier

8 contacts

9 Contact Slider

10 tabs

11 Locking mechanism

12 Bevel gear section

13 circuit board

14 circuit board

15 Drive slider

16 End area

17 End area

18 Capture bump

19 Protrusions

20 flat area

21 Leave blank

22 Receptacle

23 Flat area

24 Lock profile.

Claims (10)

1. A switching device with means for reliably indicating the position of a switch when contacts are welded, comprising:

an operating mechanism having an operating element and being operatively connected to a locking mechanism (11) via a first transmission mechanism, which moves a drive slide (15) via a second transmission mechanism;

a contact arrangement having a fixedly positioned contact carrier with a contact point, which is opposite a movable contact carrier with a contact point, which is guided in a contact slide, wherein the drive slide is connected to the contact arrangement by means of a switching lever,

characterized in that the device for reliably indicating the switching position when the contacts are welded is formed in the interior of the second gear mechanism in the form of a bevel gear section (12), wherein the bevel gear section (12) is in operative connection with the drive slide (15) and has two differently formed locking devices,

in normal opening, the drive slider moves generally downward, and opens the contacts,

during the switching-off process with welded contacts, the drive slide cannot be moved downwards due to the welded contacts.

2. A switching device according to claim 1, characterized in that the drive slider (15) is in operative connection with the bevel gear section (12) via a catch projection (18).

3. A switchgear device according to claim 2, characterized in that in the bevel gear section (12) first locking means are constructed, which are in the form of a recess (21) that geometrically matches the contour of the catch projection (18) of the drive slider (15).

4. A switching device according to claim 1 or 2, characterized in that the bevel gear section (12) has a second locking means in the form of a planar area (23) and a locking profile (24).

5. A switching device according to claim 3, characterized in that the bevel gear section (12) has a second locking means in the form of a planar area (23) and a locking profile (24).

6. A switchgear device according to claim 5, characterized in that the second locking means of the bevel gear section (12) is in active connection with the catching protrusion (18) of the drive slider (15) when the contacts are welded.

7. A switchgear according to claim 5, characterized in that, when the bevel gear section (12) is rotated in the clockwise direction, the catch projection (18) of the drive slider (15) can pass by the second locking means of the bevel gear section (12) when the contacts are not welded and engage into the first locking means for the off-state of the switchgear.

8. The switching apparatus according to claim 6, characterized in that, when the bevel gear section (12) is rotated in the clockwise direction, the catch projection (18) of the drive slide (15) can pass by the second locking means of the bevel gear section (12) when the contacts are not welded and engage into the first locking means for the off-state of the switching apparatus.

9. A switchgear device according to claim 1 or 2, characterized in that the switchgear device is a circuit breaker.

10. The switchgear as claimed in claim 8, wherein the switchgear is a circuit breaker.

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