DE2348205C3 - Method and device for manufacturing an electrical switch and a switch manufactured according to this method - Google Patents

Description

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punch, to arrange an opposing pair or pair of opposing stationary contacts and a leaf spring equipped with a movable contact on each group, to embed dir * -, e with a compressed plastic belt strap and then to remove the belt strap that temporarily holds the three clamps connects with each other. This method has the advantage that there is no possibility of dimensional error since the three clamps and conductor are always held in their relative positions as they were at the time of stamping and that the switches are suitable for mass production. Nonetheless, the work of mounting a leaf spring and a pair of opposing contacts on such terminals, which are efficiently fabricated in accordance with the method of U.S. Patent, is ineffective. In particular, the stationary contacts are produced by a problematic step in which two prefabricated, mushroom-shaped silver contacts are placed in the slots and the divergent section of the contact is hammered or rolled or printed into the slot at predetermined locations. Contacts of this type, formed by pressing silver rods into semicircular slots, are not entirely reliable in terms of bond strength and electrical conductivity. Another disadvantage is that the very poor dimensional accuracy of the contact gap * itself is a serious problem.

According to the US-PS each unit of interconnected clamps is supported by a compression molded plastic webbing embedded. The inclusion of such troublesome and ineffective pressing or casting work in the process of switch production does not represent any improvement.

The invention is therefore based on the object of a method for producing an electrical switch to create that can be mass-produced so precisely that inspection and adjustment become practically superfluous.

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

The advantages achieved by the invention are in particular that the switch with a pair of opposite contacts in a single pressing operation using a strip Contact material is made; for this purpose, silver can be used, for example, 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 the neck of a common inner end of Klein- <\ s men attached, has a sharp snap action and high durability and the same Time does not have the usual disadvantage that the snap action by the degree of attachment of the Spring is adversely affected

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 Touch can snap, provided that in parallel Way opposite surfaces of a foil conductor or sheet metal conductor lie in a plane that a Pair of opposing stationary contacts inserted fully aligned in corresponding slots are formed within the opposing surfaces that the two contacts on the Edge of the slots are caulked by means of pressure in a direction perpendicular to the sheet metal conductor or surface conductor and that the opposing faces of the two contacts have been trimmed after a hole has been punched out so that a contact gap in connection with the opposite Areas of the surface conductor or sheet metal conductor is formed.

The invention is applicable to an electrical switch of the type in which the conductor unit is exclusively the one with a mobile contact ·; equipped leaf spring is completely formed by being made from 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, which is attached to the Base of the common clamp is arranged so that it is upwards with the spring carrier as a pivot point 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 becomes the one for the purpose of clamping the clamps with each other to join, left unpunched, cut away; the upper and lower ones are more rectangular Edges of the slots that have been formed within the opposite surfaces of a sheet metal conductor are beveled by a punch prior to the application of pressure.

The inventive method for manufacturing the electrical switch according to the invention comprises essentially the steps of using I-shaped holes to punch a surface conductor or sheet metal conductor, con bars, which are essentially conform to the I-shaped holes, by punching them out of a slice fen made of contact material to use the Kontaktstük ke under pressure in the I-shaped holes to pinch the contact pieces both in the upward direction and also in the downward direction, hereinafter dii I-shaped contact pieces across their center ir To perforate connection with the adhering section of the surrounding sheet metal conductor and thereby con to form clock gaps and the opposing surfaces of the resulting pair-wise contacts by express Finishing regrooving, which is carried out by means of a press sens.

A device / for making electric scarf The invention comprises means comprising a strip of electrically conductive material pushes, a press for punching the strip, oii pressing tool and a die for punching out a I-shaped hole in the strip, a facility

for conveying a strip of contact material into a position directly above the I-shaped hole, a die or a pressing tool for punching out a contact piece corresponding to the I-shaped hole from the strip of contact material, a pressing tool that just comes out of the strips cut contact piece in the I-shaped hole including suppressed, a bearing surface which holds the strip of electrically conductive material in a position in which the I-shaped contact piece is caulked subsequent to insertion 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 connected portion of the surrounding electrically conductive material, means for recutting the opposite faces of the resulting gap-separated contacts, and means for punching out the superfluous portion of the electrical conductive material, so that conductor and clamp n are formed.

The term "I-shaped" is used broadly to refer to all of the shapes by which a pair of opposing contacts can be obtained from a single contact piece .

According to the invention, a strip of electrically conductive material! perforated with I-shaped holes. Contact materials shaped to correspond to the I-shaped holes are inserted into the holes and caulked. Then the I-shaped contact materials are perforated across their center in connection with the subsequent or connected parts of the electrically conductive material in order to divide each contact material into two contacts which are separated by a contact gap formed between them. A leaf spring, which is equipped at one end with a movable contact which is to be inserted into the contact gap, is held in its position, which is not an immobile state, by simply inserting its other end around the stump or attachment of a spring carrier will. Clamps, which are held in their fixed relative position by means of a strap which connects them to one another, are attached to a plastic housing with an adhesive agent or an adhesive. After fastening, the webbing is cut off.

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

F i g. 1 is a schematic diagram illustrating a preferred embodiment of a method for manufacturing electrical switches according to the invention;

F i g. 2 a top view showing an electric Schaher illustrated, which is embedded in one of two segments which is a prefabricated plastic housing form, wherein the electrical switch has terminals that are interconnected by a tape are as shown in oem on the far left in FIG. 1 block of the strip of successive blocks shown has been obtained, and 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,

F i g. 4 is a cross-sectional view illustrating a metal strip with a punched hole for inserting a piece of silver as a contact material;

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

F i g. 6 the third step of the process shown in FIG. 1 illustrated series of steps in which a piece of silver 15 ′ 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 piece of silver 15 'is inserted into the hole 12 and immediately pried with a force exerted on its upper and lower ends,
F i g. 8A and 8B schematically show the same step in which the piece of silver 15 'is pried into the hole with a greater height,

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

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,
F i g. 12 a top view of a leaf spring F,
F i g. 13 a side view of the leaf spring F,
F i g. 14A and UB schematically the functionality of the leaf spring F,

F i g. 15 and 16 are a plan view and a cross-sectional view, respectively a preferred embodiment of a plastic housing with which the series of through the Pressing operation designed clamps is connected by means of an adhesive.

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

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 is the method of manufacturing an electrical switch according to the invention is illustrated In this method, nine consecutive presses, each of which has a cutting die and a die or a template, actuated au perform a sheet metal strip 11 gradually successive manufacturing steps when this in is advanced one block at a time. In the preferred embodiment illustrated in this diagram, a strip of electrically conductive material is advanced one block at a time, performing one manufacturing step at a time in the operational sequence. In more detail, a press equipped with upper and lower dies or Preßwerkzeu conditions similar to those shown in Figs. V and 11 is operated, and after each stroke of the press either the paired punching tools or the processed strip of electrically conductive material around one block or one movement step at a time for the next 6s punching stroke.

The strip 11. which is made of a copper alloy is 21 mm wide. 0.8 mm thick and divided into blocks a unit length of 20 mm. The Roman Zi

far I 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 11 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 means for advancing the strip 11 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 11, a punching tool or die 16 '(F- "i g. 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. In the fourth step, an anvil or a Support surface located below is used for the contact material 15 'to be pushed into position in the hole to be caulked in. In the fifth step, a punch 31 and a die 31' (Figs. 17 and 18) are used which are adapted to punch an elongated hole 20 across the center I-shaped contact material 15 ', as shown in Figures 9 and 10. A punch 32 and a die 32' (Figure 9) . 19 and 20) which the opposite n surfaces of the contacts can be used in the sixth step. From the seventh to the ninth step, punching tools and dies are used which serve to punch out unnecessary sections from the strip 11. The tenth and final step requires a conveyor that advances clamps that are belt-connected 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 positions where the opposite pair of stationary contacts P and P is expected to fall (Fig. 2) is punched out. In the embodiment shown, the upper and lower ends of the I-shaped hole protrude in the form of "hairlines"("serifs"). however, these protrusions can be omitted if circumstances require. At the same time, a hole 13 is punched through each of the clamps A. B and C (Fig. 2) to facilitate guidance. At this stage, the I-shaped hole has a rectangular cross-section, as shown in FIG. 4 is illustrated. If this cross-section were left unchanged in this form, the piece of silver to be inserted into the hole could drift in the vertical direction. As a result, in order to prevent this movement, the upper and lower right-angled edges of the hole are chamfered by pressing in the second step. At the same time, a hole 14 is punched in a pattern so that individual, separate clips are formed.

In the third step, the Silberstreil'en becomes 15th of the in is advanced in a direction perpendicular to the strip 11 of electrically conductive material, to which Punch 16 'out directly above the L-shaped Hole 12 is arranged. as shown in FIG. 6 is shown. Using the sum / tool 16, a piece of silver is which has a shape that corresponds exactly to the I-shaped hole 12 or only slightly larger as this is, punched out of the silver strip 15 and

ίο pressed directly into the I-shaped hole. Since the hole 12 is held on the anvil or the support surface, the punching tool 16 can be operated in such a way that it produces a slight prying movement on the piece of silver 15 'against the I-shaped hole 12. In 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 silver piece 15 ', which during from the previous step has been pushed into place. both up and down, either in the in Figs. 7A and 7B or in FIGS. 8A and 8B depending on the manner shown caulked from the height of the piece of silver. In Fig. 7 illustrates a case in which both the silver piece 15 'and the strip 11 of electrically conductive material have an equal thickness of 0.8 mm. In this case the top and lower circumference of the piece of silver 15 'caulked in such a way that that they are stretched to the upper and lower beveled edges of the during the second Cover the crotch formed L-shaped hole. This caulking is carried out by a couple are moved towards each other by wedge-shaped punching tools in order to exert pressure along the circumference.

.15 to exercise. If the silver piece used as the contact material is of a smaller diameter, the caulking can be carried out by applying pressure to the centers of the silver piece rather than the circumference. As a result of the caulking, the piece of silver 15 'and the strip 11 are securely connected, and a contact plane or contact surface with low electrical resistance is formed at the same time. If a piece of silver 15 'is used which has a greater thickness than the strip 11, the piece of silver 15' only needs to be squeezed or compressed, as shown in FIG. 8 is illustrated. As a result, the silver piece 15 'is deformed so that it conforms to the hole in substantially the same way as if a rivet were in a connection position, ie from the position shown in FIG. 8A is flattened into the shape shown in Fig. 8B. In that case, the third step can be carried out so that the required caulking of the silver piece 15 'occurs simultaneously with its insertion into the I-shaped hole, rather than inserting the fourth step solely for the purpose of caulking To push material outwards, it is carried out before the designer of the clamps A. and C, in order to prevent an otherwise possible dimensional error in the finished product.

In the fifth step, an elongated hole 20 is the one between the pair of opposed Contacts to be inserted gap forms, punched out

f> 5 as shown in FIGS. 9A and 9B is illustrated. This perforation or perforation leads to the formation of a pair of opposing silver contacts / and P (Y i g. 2). that on all sides except for the excl

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stamped ropes surrounded by the copper alloy material are.

In the sixth step, the opposite Areas of the contacts which are directed towards one another across the hole 20 forming the gap, a re-cutting treatment subjected to a smooth surface for the silver contacts 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 punching tool 3t, which is used for lancing out the hole 20 across the piece of silver 15 ' will be of such a shape that a margin of 0.08 mm remains on part 33 for re-cutting. A precise finishing of the Silberkoniakle for one A smooth surface and a precise gap are created by cutting the edge using the trimming slicing tool 32 (Fig. 19 and 20) is trimmed. The correct thickness for this edge for trimming is on the order of 10% of the thickness of the Strip II. The re-cutting punching tool and the die must not have any play. The two protuberances and stool 35 and 36 at the lower end of the punching tool shown in FIGS. 19 and 20, respectively serve as guides. They slide along holes made by the in FIG. 17 and 18 shown Punching tool are formed, and lead the regrooving part 34 of the punching tool 32 in correct way.

The steps described so far complete the essential part of establishing contact. In the seventh and eighth step, a hole separating the clamps is punched out and becomes the unnecessary one Section of the strip removed by die cutting. The cutting and punching operation. the one in the ninth Step performed results in a three-terminal block as a unitary part. This block is in the Tenth step taken out.

The three terminals A. B and C that 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. a stepped portion for holding the terminals immobile when the terminals are between the upper and lower ones Segment of the housing are encompassed, a cavity 23 which the movable contact H and the leaf spring F. which the movable contact H carries. There is freedom of movement in the housing, and a groove 24 for receiving a bumper or operating rod G. which allows vertical movement of the operating rod. In the preferred embodiment illustrated, the grooves 21 for receiving the clamps and the stepped portion 22 for holding the clamps immobile are formed on only one of the two segments E and E of each housing. However, the two segments and E can be made in complete symmetry if circumstances so require. The leaf spring F must be attached to a spring support 25 at the base of the terminal A before the switch is firmly enclosed in the housing by means of adhesive. From a practical point of view, the process of enclosing or enclosing! " in the, o housing is preferably carried out manually. The leaf spring F, the one shown in FIGS. 12 and 13, is attached by slightly bending the tongue 26 so that the gap 27 is widened, and in this state it is simply hooked onto the neck or shoulder 25 of the clamp A. Thus, assembling can be carried out easily, and the spring of the completed switch exhibits uniform performance. The leaf spring F can be stamped out from a strip of spring material and is therefore suitable for mass production. Since no bending treatment needs to be carried out, a possible change in the spring behavior, which could be ascribed to a bending operation, is excluded. In addition, the manufacturing costs are thereby reduced.

The interconnected terminals A. B and C with the leaf spring F inserted around the spring support 25 are inserted into their position together with the actuating rod G in the corresponding grooves formed in the switch housing. In contrast to a conventional switch housing, the groove width of the switch housing according to the invention has nothing to do with the setting of the relative position of the terminals. As a result, the grooves can be made with a sufficient width to facilitate the insertion of the clamps. The relative position of these terminals is first maintained by a band D connecting them to one another and then, after the band has been removed, by the adhesive with which the switch has been fixed in the interior of the housing. This contributes to a small switch in which the upper and lower segments of the switch housing are permanently attached to one another by an adhesive. If the circumstances so require, the switch can only be attached to one of the two segments so that the switch housing can be opened.

The invention is not limited only to the preferred embodiment described above in which all of the terminals in a switch unit have been punched out of a single piece by pressing, but also at all electrical switches that have a pair of opposite one another Have contacts, and similar electrical switches applicable.

In addition 7 sheets of drawings

Claims (6)

Patent claims: 1. A method for producing an electrical switch with a pair of opposite, stationary contacts and a movable contact which alternately snaps with the stationary contacts in contact contact, characterized in that two opposite contact holding surfaces of a flat conductor or sheet metal conductor (11) in one plane be arranged that a pair of opposed stationary contacts (P, P) are fully inserted into associated slots formed within the opposed surfaces (F) so that the opposed surfaces (F) of the Kontakie (P, P) in the are essentially aligned with the contact holding surfaces of the surface conductor (11) so that the two contacts (P. P) are wedged onto the edge of the slot by means of a pressure which is exerted perpendicular to the sheet metal conductor (U), and that the opposite surfaces (S) of the two contacts after punching out a hole to form a contact gap in connection with d en opposite surfaces of the sheet metal conductor (11) are trimmed. 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 (E, E) which form a separately manufactured switch housing, and that after Attach the ribbon (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 (i2) are punched through a surface conductor or sheet metal conductor (11) that contact pieces (15 '), which are essentially in correspond to the shape of the I-shaped holes (12), formed by punching out of a strip of contact material (15), that the contact pieces (15 ') are inserted under pressure into the I-shaped holes (12), that the contact Mosquito (15 ') are pried 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 Biechlcilers to form contact gaps and that the opposite surfaces of the resulting contact pair (P, P) are finished by a re-cutting treatment using pressing. 5. According to the method according to one of claims I to 4 produced electrical switch, characterized in that the leaf spring (F) equipped at one end with a movable contact (77) at its other end between the end of an inner hole and the front The end of 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 upwards and downwards and the end of the inner hole as Pivot point is used. 6. Device for producing an electrical switch, marked by a device for moving a strip (11) 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 (U) ₁ by 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) from the contact material strip by a punching tool (16) which pushes the contact piece (15') just cut out of the strip into the I-shaped hole underneath (52) pushes through a support surface that the. Holds strip of electrically conductive material in a position so that the I-shaped contact piece (15 ') can be pried after insertion into aas hole, by a punching 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 a device for carrying out 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 conductors and connections. 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 mockery 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, a fast one Ensure operation and rule out problems or failures. For this reason, the usual electrical switches used in the conventional Way to be made, a lot of time and labor for the workers of the inspection and a possible readjustment, which must be carried out subsequent to the completion of the assembly of the parts. In the US PS 89 703 describes a process that makes significant improvements in the manufacture of electrical Switch provides. There is described a method comprising the steps. Groups of three each Terminals connected to one another from a strip of electrically!