DE2348205B2 - METHOD AND DEVICE FOR MANUFACTURING AN ELECTRICAL SWITCH AND A SWITCH MANUFACTURED BY THIS METHOD - Google Patents

Description

The invention relates to a method for producing an electrical switch according to the preamble of claim 1. The invention also relates to an apparatus for producing an electrical Switch and a switch produced by this method.

The quality and the performance or the performance behavior electrical switches greatly affect the quality of the various electrical Apparatus and devices using these switches. In extreme cases, it can fail an electrical switch could even put a person at risk if the devices containing this switch were to be used operated or used. Electrical switches must therefore be very stable and safe, tine fast Ensure operation and rule out problems or failures. For this reason, the usual electrical switches that are made in the conventional way take a lot of time and labor for that Workers inspecting and a possible re-enactment following the completion of the assembly the parts need to be executed. In US-PS 89 703 a method is described, the essential Provides improvements in the manufacture of electrical switches. A procedure is described there which includes the steps. Groups of three clamps each in interconnected form a strip of electrically conductive material

punch, an opposite pair on each group tow. Pair of opposed stationary contacts and one equipped with a movable contact To arrange leaf spring, this with a press

^ Embed the elastic webbing and then the webbing to remove the three clamps "temporarily" one below the other This method has the advantage that there is no possibility of dimensional error is given, since the three terminals and the conductor always Uli their relative position to which they are held Stop the punching time and that the switches are suitable for mass production. Nonetheless instructs the work of attaching a leaf spring and a pair of opposing contacts none on such clips which are effectively manufactured in accordance with the method of U.S. Patent Efficiency on. In particular, the stationary contacts become through a problem-laden step manufactured, in which two prefabricated, mushroom-shaped Silver contacts are placed in the slots and the divergent portion of the contact at predetermined Places in the slot is hammered, rolled or pressed. Contacts of this type made by pressing Shaped by silver bars into semicircular slots are not entirely reliable as to Bond strength and electrical conductivity. Another disadvantage is that the very low Dimensional accuracy of the contact gap itself is a serious problem

According to the US-PS, each unit of interconnected clamps is secured by a molded plastic webbing embedded The inclusion of such a problematic one and provides little effective molding work in the process of switch production no improvement.

The invention is therefore based on the object To create a method of manufacturing an electrical switch that is so precise in mass production can be manufactured so that inspection and readjustment are practically unnecessary.

According to the invention, this object is achieved by the features of the characterizing part of claim 1 solved.

The advantages achieved with the invention are in particular in that the switch has a pair of opposing contacts in a single one Pressing operation is made using a strip of contact material; for example Silver can be used, which is fed to the production line for the electrical switches. There- at high quality, stationary contacts are created by a single pressing operation using a strip of contact material such as silver.

Another advantage of the invention is that the electrical switch in a single pressing operation using a strip of contact material such as silver and subsequently in prefabricated high-efficiency housings is included.

Finally, an advantage of the invention is that the electrical switch on the basis of a leaf spring, which are equipped with a movable contact at one end and around the other end attached to the neck of a common inner end by gills, a sharp snap action and has high durability and does not have the usual disadvantage at the same '/ pit (Ιρπ that the Snap action is adversely affected by the degree of attachment of the spring

According to the invention is an electrical switch of the type having a pair of opposed stationary Contacts and a movable contact, which alternatively connects to the two stationary contacts in Can snap touch, provided that in a parallel manner opposite throat of a foil conductor or sheet metal conductor lie in a plane that a pair of opposing stationary contacts are inserted fully aligned in corresponding slots within the opposing faces are designed that the two contacts are caulked onto the edge of the slots by means of pressure, which in a direction perpendicular to the sheet metal conductor or surface conductor has been exercised, and that the opposite Surfaces of the two contacts have been trimmed after a hole has been punched out so that a contact gap in connection with the opposite surfaces of the surface conductor or sheet metal conductor is trained

The invention is applicable to an electrical switch of the type in which the conductor unit is exclusively the leaf spring equipped with a movable contact is completely formed by being made of a sheet metal conductor is punched out by a pressing operation and as a result lies in one plane; the A leaf spring equipped with a movable contact is used around the spring carrier Base of the common clamp is arranged so that it is upwards with the spring support as a fulcrum and can move downwards; the terminals of the electrical switch operated in the above-mentioned manner is completely punched out of a metal strip with an adhesive agent or an adhesive attached to at least one of the two segments that form a separately molded switch housing, and after this fastening, the webbing, which is used for the purpose of clamping, is temporarily interconnected to join, left unpunched, cut away; the top and bottom right-angled Edges of the slots that have been formed within the opposite faces of a sheet metal conductor are beveled by a punch tool prior to the application of pressure.

The inventive method for manufacturing the electrical switch according to the invention comprises essentially the steps of punching I-shaped holes through a flat conductor or sheet metal conductor, contact pieces, substantially conforming to the I-shaped holes by punching them out of a strip make of contact material, insert the contact pieces under pressure into the I-shaped holes, to pinch the contact pieces both in the upward direction and in the downward direction, hereinafter the I-shaped contact pieces across the middle ir connection with the adhering portion of the vice to perforate benden sheet metal conductor and thereby to form contact gaps and the opposite Fla ch «: n of the resulting pairwise contacts through eii Finishing regrooving, which is carried out by means of a press sens.

An apparatus for making electrical scarf ter according to the invention comprises a device, di pushes a strip of electrically conductive material, a press for punching the strip, ei Pre-opening tool and a die for punching out an I-shaped hole in the strip, a device

for conveying a strip of contact material to a position directly over the I-shaped hole, a Die or a pressing tool for punching out a contact piece that corresponds to the I-shaped hole, from the strip of contact material, a pressing tool which the one just cut out of the strip Contact piece presses into the I-shaped hole below, a bearing surface that holds the strip of electrically conductive material in a position in which the I-shaped contact piece subsequent to the insertion is pried into the hole, a pressing tool and a die for punching a hole across the center of the I-shaped contact piece in connection with the bonded portion of the surrounding electrically conductive material, means for recutting the opposing faces of the resulting gap separated contacts and means for punching out the superfluous portion of the electrically conductive material to form conductors and clamps are formed.

The term "I-shaped" is used broadly and refers to all of the shapes that a couple can use can be obtained from opposite contacts from a single contact piece.

According to the invention, a strip of electrically conductive material is perforated or perforated with I-shaped holes. Contact materials that so shaped to correspond to the I-shaped holes are inserted into the holes and caulked. Then the I-shaped contact materials across their center in connection with the subsequent or connected parts of the electrical conductive material perforated to divide each contact material into two contacts, the are separated by a contact gap formed between them. A leaf spring at one end is equipped with a movable contact that is to be inserted into the contact gap A position that does not represent an immobile condition is held by simply turning its other end around the Stump or approach of a spring carrier is used. Clamps, which means in their fixed relative position a strap that connects these with each other are held with an adhesive Agent or an adhesive attached to a plastic housing After attaching the belt strap cut off.

The invention is described below with reference to the drawing, for example; in this shows:

1 is a schematic diagram illustrating a preferred embodiment of a method for manufacturing electrical switches according to the invention

F s g. 2 is a plan view showing an electrical switch illustrated, which is embedded in one of two segments which is a prefabricated plastic housing form, wherein the electrical switch has terminals which are connected to one another by a band are as shown in the far left in FIG. 1 block of the strip of successive blocks shown has been obtained and with a leaf spring in FIG their position has been established

F i g. 3 is a side elevation of the electrical switch showing is completely enclosed in a prefabricated plastic housing

Figure 4 is a cross-sectional view showing a metal strip with a punched hole for inserting a piece of silver as a contact material vividly,

F i g. Figure 5 is a cross-sectional view illustrating the top and bottom as in the same strip right-angled edges of the hole are beveled under pressure,

F i g. 6 the third step of the process shown in FIG. 1 demonstration clear series of steps in which a piece of silver 15 'is punched out of a silver strip 15 and directly into the hole 12 previously punched in the strip 11 ίο is pressed,

F i g. 7A and 7B schematically show a step in which the silver piece 15 'is inserted into the hole 12 and is immediately wedged in with the force exerted on its upper and lower end, 8A and 8B schematically show the same step in which the piece of silver 15 'is wedged into the hole with a greater height,

F i g. 9A and 9B schematically show a step in which an elongated hole 20, which the silver piece 15 'crosses in the middle and extends into the adjoining or connected section of the surrounding electrically conductive material, is punched out, so that the piece of silver 15 'is spliced or split in the middle,

F i g. 10 and 11 are plan views illustrating a preferred embodiment of a set of upper and lower continuous punches or dies used for the type of die shown in FIG. 1 can be used, FIG. 12 a top view of a leaf spring F,

F i g. 13 is a side view of the leaf spring F.

14A and 14B schematically the mode of operation of the leaf spring F,

F i g. 15 and 16 a plan view and a cross-sectional

view of a preferred embodiment of a

Plastic housing with which the series of through the Pressing operation designed clamps by means of a Adhesive is connected,

F i g. 17 and 18 are a plan view and a side view, respectively, of a punching tool used to split the piece of silver 15 ', and FIGS

F i g. 19 and 20 a plan view and a side view, respectively, of a punching tool which is used for the operation of the Regrooving is used.

In Fig. 1 illustrates the method of making electrical switches in accordance with the invention. In this method, nine successive presses, each of which has a stamping iron and a die or a die, are actuated in order to perform successive manufacturing steps in stages a sheet metal strip 11 when it is advanced one block at a time. At the in The preferred embodiment illustrated in this diagram is a strip of electrically conductive SS material advanced one block at a time to perform one manufacturing step at a time in the operational sequence press equipped with upper and lower dies or pressing tools, similar to those in FIGS. 10 and 11 actuated and after each stroke of the Press either the punching tools arranged in pairs or the processed strip electrically conductive material one block at a time for the next Punching stroke moved

The strip 11, which is made of a copper alloy, is 21 mm wide, OJS mm thick and divided into blocks with a unit length of 20 mm. The Roman numerals

far 1 to X, which are shown in the drawing under the lower edge of the strip ;, are serial numbers that identify the production sequence. A strip of silver serving as the contact material has a width of 5.0 mm and the same thickness of 0.8 mm as the strip ti and is fed at a pitch of 5 mm. The main facilities and tools used in this work process are described below. A press and a device for advancing the strip II of electrically conductive material and the silver strip 15 are required. They are conventional devices as they are usually used for the pressing operation and therefore do not need any representation to explain them. In the first step, a punch 30 and a die 30 'are used which are suitable for punching an I-shaped hole, as shown in FIGS. 10 and 11 is shown. The third step requires a feed device which feeds the strip 15 of contact material, usually silver, onto the I-shaped hole 12 in a direction perpendicular to the strip II, a punching tool or a die 16 '(FIGS. 6 and 11) in order to punch an I-shaped contact material from the silver strip 15, and a punching tool 16 which is used to press the contact material 15 'directly into the I-shaped hole 12 below. In the fourth step, an anvil or support surface located below is used for the contact material 15 'to be pressed into place in the hole to be caulked. In the fifth step, a punch 31 and a die 31 '(Figs. 17 and 18) are used which are suitable for punching an elongated hole 20 across the I-shaped contact material 15' in the center, as shown in FIGS F i g. 9 and 10 is shown. A punch 32 and a die 32 '(Figs. 19 and 20). which can form the opposite surfaces of the contacts are used in the sixth step. The tenth and final step requires a conveyor that advances clamps that are webbing connected to a belt for deposition or assembly. The individual manufacturing steps are described below. In the first step, the I-shaped hole 12 having its upper and lower ends at locations where the opposite pair of stationary contacts and P is expected to fall (Fig. 2) is punched out In the illustrated embodiment, the upper and lower ends of the I-shaped hole project in the form of "serifs", but these projections can be omitted if circumstances so require. At the same toe, a hole 13 is punched through each of the clamps A, B and C (Figure 2) to facilitate guidance. At this stage, the I-shaped hole has a rectangular cross-section, as shown in FIG. 4 If this cross-section were left unchanged in this form, the piece of silver to be inserted into the hole could move freely in the vertical direction. As a result, in order to prevent this movement, the upper and lower right-angled edges of the hole are beveled by pressing in the second step. At the same toe, a hole 14 is punched in a pattern so that individual, separate clips are formed.

In the third step, the silver strip 15, which is in is advanced in a direction perpendicular to the strip U of electrically conductive material, to which Punch 16 'out, which is arranged directly above the L-shaped hole 12, as shown in FIG. 6 shown is. By means of the punching tool 16 is a piece of silver which has a shape that of the I-shaped Hole 12 corresponds exactly or is only slightly larger than this, punched out of the silver strip 15 and

ίο printed directly into the I-shaped hole Since that Hole 12 is held on the anvil or the support surface, the punch 16 can be operated so that there is a slight caulking on the Silver piece 15 'is generated against the I-shaped hole 12. In During this step, a hole 19 is punched out at the same time in order to form an opening between the clamps A and β.

In the fourth step, the piece of silver 15 'that was in its position during the previous step has been pressed both up and down, either in the direction shown in Figs. 7A and 7B or in the F i g. 8A and 8B the type and manner shown depending on the height of the piece of silver. In F i g. 7 is illustrated a case in which both the silver piece 15 'as well as the strip U made of electrically conductive material have an equal thickness of 0.8 mm. In this case, the upper and lower peripheries of the silver piece 15 'are caulked so that they are expanded to the upper and cover the lower beveled edges of the I-shaped hole formed during the second step. This caulking is done by moving a pair of wedge-shaped punching tools towards each other to apply pressure along the perimeter. to practice. When the piece of silver used as the contact material has a smaller diameter The caulking can be done by applying pressure to the centers of the silver piece rather than the perimeters. As a result of the caulking which the silver piece 15 'and the strip 11 are securely connected, and at the same time it becomes a contact plane or contact surface with low electrical power Resistance formed when a piece of silver 15 'is used, which is thicker than the strip 11 has the Silberstfick 15 'only squeezed or to be compressed as shown in FIG. 8 is illustrated. As a result, the silver piece 15 becomes deformed so that it conforms to the hole in much the same way as if a rivet were to fit together Connection position, & h. of the in F i g. The shape shown in FIG. 8A is flattened into the shape shown in FIG. 8B will. In that case, the third step can be carried out so that the necessary caulking of the silver Piece 15 'simultaneously with its insertion in there:

ss I-shaped hole is made instead of the fourth step finally insert for the purpose of caulking since caulking tends to insert the surrounding mate rial to the outside, it will be before the design! of terminals A, Bunch C carried out to another if possible, to prevent dimensional errors in the finished product.

In the fifth step, an elongated hole 2t defining a gap to be inserted between the pair of opposing contacts

6s as shown in Figs. 9A and 9B is illustrated. This perforation results in the formation of a pair of opposing silver contacts 1 and P ( FIG. 2) on all sides except for the outlined

409528/27

punched side are surrounded by the copper alloy material.

In the sixth step, the opposite Areas of the contacts which are directed towards one another across the hole 20 forming the gap are subjected to a re-cutting treatment in order to give the silver contacts a smooth surface in a final treatment to give and at the same time to adjust the contact gap to a predetermined size. According to Fig. 17 has the punch 31 which is used for punching out the hole 20 across the piece of silver 15 ' becomes such a figure. that a margin of 0.08 mm remains on the part 33 for trimming. One Precise finishing of the silver contacts for a smooth surface and an accurate gap is accomplished by trimming the edge using the trimming punch 32 (Figures 19 and 20). The correct thickness for this edge for trimming is on the order of 10% of the thickness of the Strip ti. The recutting punching tool and the die must not have any play. The two protuberances or stools 35 and 36 on the lower one The ends of the punching tool shown in FIGS. 19 and 20 serve as guides. They slide along Holes formed by the punch shown in Figs. 17 and 18, and lead the trimming part 34 of the punch 32 in the correct manner.

The steps described so far complete the essential part of establishing contact. In the seventh and eighth step, a hole will be made that the clamps will is punched out and the unnecessary portion of the strip is removed by punching. Of the The cutting and punching operation performed in the ninth step results in a three-clamp block as a unitary part. This block is in the Tenth step taken out.

The three clamps A. B and C, which form the conductor section except for the leaf spring F , are held in their fixed relative position by means of a fixed strap D. Meanwhile, switch housings are mass-produced using a suitable plastic material, each of which is provided with three grooves to receive the three terminals A, B and C and a stepped portion 22 for holding the terminals immobile when the terminals are between the upper and lower segments of the housing, a cavity 23 which the movable contact H and the leaf spring F. which carries the movable contact H , freedom of movement in the housing, and a groove 24 for receiving a push rod or operating rod G, the vertical movement of the operating rod In the illustrated preferred Atisführungform the grooves 21 for receiving the clamps and the stepped Tefl 22 for the immovable Clamps formed on only one of the two segments E and t of each housing. However, the two segments E and E can be manufactured in complete symmetry if circumstances so require.

The leaf spring F must be attached to a spring support 25 ai the base of the terminal A before de switch is firmly grasped in the housing by means of adhesive. From a practical point of view, the operation of enclosing in the

■ ο housing is advantageously carried out manually Di <leaf spring F, which is one in the F i g. 12 and 13 can have a special design, is introduced by the tongue 26 is slightly bent so that the gap 27 is widened, and in this state simply on the neck or neck 25 of the clamp / is hooked. Thus, assembling can be carried out easily, and the spring of the finished! Switch has a uniform performance. The leaf spring F can consist of a strip of:

Spring material are punched out and is therefore füi Suitable for mass production Since no bending action needs to be carried out, a possible Before changing the spring behavior, which could be ascribed to a bending operation, is ruled out In addition, the production costs are thereby reduced.

The interconnected terminals A, B to C with the Blattfe of F inserted around the spring support 25 are in their position together with the Actuate transmission rod G inserted into the corresponding grooves formed in the switch housing In contrast; to a conventional switch housing the Nu tenbreite of the switch housing according to the invention has nothing to do with the setting of the relative position de Clamps to do. As a result, the grooves can be made with sufficient width to facilitate the insertion of the clamps. The relative position of these clamps is only determined by a band D connecting them lower and then after removal the tape retained by the adhesive, mi that the switch has been secured inside the housing This contributes to a small switch which the upper and lower segments of the switch housing are permanently attached to one another by means of an adhesive are attached. When the circumstances called, came the switch also only attach to one of the two segments be stigt, so that the switch housing opened who can.

The invention is not only limited to the above «

preferred embodiment in which all clamps ii a switch unit from a single piece durcl Presses have been punched out, but also be all electrical switches that have a pair of against have overlying contacts, and the like electrical switches applicable.

In addition 7 sheets of drawings

Claims (6)

* ■ "■■ * 1 ** · - Patent claims: % i. A method of manufacturing an electrical switch using a pair of opposite one another. stationary contacts and a movable contact which alternately snaps into contact with the stationary contacts, characterized in that two opposite contact holding surfaces of a flat conductor or sheet metal conductor (11) are arranged in one plane, that a pair of opposite, stationary contacts (P, P ) is completely inserted into associated slots which are formed within the opposing surfaces (F) so that the opposing surfaces (F) of the contacts (P, P) are substantially aligned with the contact holding surfaces of the surface conductor (U) so that the two contacts (P, P) are caulked onto the edge of the slot by means of a pressure which is exerted perpendicular to the sheet metal conductor (11), and that the opposite surfaces (S) of the two contacts after punching a hole to form a contact gap in connection with cut the opposite surfaces of the sheet metal conductor (U). 2. A method for producing an electrical switch according to claim 1, characterized in that the entire conductor with the exception of a leaf spring (F) which has a movable contact (H) is made by punching out of a sheet metal conductor (11) by means of pressing and as a result lies in one plane. 3. A method for producing an electrical switch according to one of claims 1 or 2, characterized in that the connections are attached by means of an adhesive to at least one of two segments (EE) which form a separately manufactured switch housing, and that after the attachment Tape (D) that has not been punched to temporarily connect the terminals (A, B, C) together, is cut off. 4. A method for producing an electrical switch according to one of claims 1 to 3, characterized in that I-shaped holes (12) are punched through a surface conductor or sheet metal conductor (11), that contact pieces (15 '). which essentially correspond in shape to the I-shaped holes (12) are formed by punching out a strip of contact material (15) so that the contact pieces (15 ') are inserted into the I-shaped holes (12) under pressure, that the contact pieces (15 ') are caulked both upwards and downwards, that then the I-shaped contact pieces (15) are perforated or perforated across their center in connection with the adjoining section of the surrounding sheet metal conductor to form contact gaps and that the opposite surfaces of the resulting contact pair (P, P) are finished by a re-cutting treatment by means of pressing. 5. According to the method according to one of claims 1 to 4 produced electrical switch, characterized in that the leaf spring (F) equipped at one end with a movable contact (H ) at its other end between the end of an inner hole and the front end the leaf spring tongue (26) has a gap which can be inserted around a spring support {25) which is arranged at the base of the common connection, the leaf spring (F) being movable up and down and the end of the inner hole as a fulcrum serves 6. Device for producing an electrical switch, characterized by a device for moving a strip (11) made of electrically conductive material, by a press for punching the strip (11), by a pressing tool (30) and a die (30 ') for punching out an I-shaped hole (12) in the strip (11), by means of a device for transporting a strip of contact material into a layer directly above the I-shaped hole (12), by a punching tool or a die (16 *) ) for punching out a contact piece (15 ') corresponding to the I-shaped hole (12) in the form of the contact material strip, by a punching tool (16), which the contact piece (15 ^r ) just cut out of the strip into the I-shaped one below Hole (12) pushes through a support surface which holds the strip of electrically conductive material in one position so that the I-shaped contact piece (15 ') can be wedged into the hole after it has been inserted, through a St. tipping tool (31) and a die for punching a hole (20) across the center of the I-shaped contact piece in connection with the adjoining section of the surrounding electrically conductive material, by means of a device for performing a re-cutting treatment on the opposite surfaces of the resulting, contacts separated by a gap, and by a device for punching out superfluous parts of the electrically conductive material for the formation of the conductors and connections.