DE2348205A1 - ELECTRICAL SWITCH AND METHOD AND DEVICE FOR MANUFACTURING THIS - Google Patents

Description

DR. MÖLLER-BORE DlPL-PHYS. DR. MANITZ CIPL-CKEM. DR. DEUFEL

DIPL-ING. FINSTERWALD DIPL-ING. G RAM KOW

PATENT LAWYERS

Munich, 25th SEP. 1173

Hl / Sv -T 1258

TAKANO PRECISION INDUSTRY CO., LTD. IO32, Aza-Ueno, IPukushima, Yatsuomachi, Toyama-ken,

Electrical switch and method and apparatus for making of this _

The invention relates to an electrical switch of the type having a pair of opposed stationary contacts and has a movable contact and can be produced by pressing, as well as an apparatus and a method for making this switch.

The quality and the performance or the performance behavior electrical switches have no small effect on the quality of various electrical equipment, who use this switch. In an extreme case, an electrical switch can even fail endanger the safety of any person operating equipment containing this switch. All of these electrical switches must therefore have a stable quality, a

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Ensure fast operation and rule out problems or failures. For this reason, usual electrical switches made in the conventional way take a lot of time and labor for that Working inspection and possible readjustment following the completion of the assembly of the Parts need to be run. In U.S. Patent 3,189,03 describes a method which provides significant improvements in the manufacture of electrical switches. A method is described therein which comprises the steps of groups of three clamps in each other connected form from a strip of electrically conductive Punch out material on each group an opposing pair or pair of opposing stationary To arrange contacts and a leaf spring equipped with a movable contact, this with a compression-molded plastic belt strap to embed and then remove the webbing that temporarily connects the three terminals with one another. This method has the advantage that there is no possibility of one Dimensional error is given because the three clamps and the Heads are always held in their relative position that they were in at the time of punching, and that the Switches are suitable for mass production. Nonetheless, the work of attaching a leaf spring and a pair of opposing contacts on such terminals, according to the method from OS-PS can be produced effectively does not have any degree of efficiency. In particular, the stationary contacts are through a problem-laden step in which two prefabricated, mushroom-shaped silver contacts 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 rods into semicircular slots are not completely reliable as to the

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Bond strength and electrical conductivity. Another disadvantage is that the very low dimensional accuracy of the contact gap itself poses a serious problem.

According to the US-ES, each unit is interconnected by one another Clamps embedded by a press-molded plastic webbing. The inclusion of such troublesome and ineffective molding work in the process switch production does not represent any improvement.

It is therefore an object of the invention to provide an electrical switch which is suitable for mass production and enables such a precise production that the work of inspection and readjustment is practically superfluous will.

Advantageously, according to the invention, there is an electrical switch with a pair of opposing contacts provided by a single pressing operation using a strip of contact material such as Silver, which is fed to the production line for the electrical switches, is produced.

According to the invention, a method is advantageously provided with the high quality stationary contacts in an electrical switch through a single pressing operation can be produced using a strip of contact material such as silver.

Another advantage of the invention is that the electrical switch in a single pressing operation when using a strip made of contact material such as silver and subsequently in prefabricated Enclosed housing with high efficiency.

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Finally, there is an advantage of the invention that the electrical switch due to a leaf spring that on one end of this equipped with a movable contact and at its other end around the neck of a joint is attached to the inner end of clamps, has a sharp snap action and high durability and the for at the same time does not have the usual disadvantage that the snap action is disadvantageous due to the degree of attachment of the spring is affected.

In accordance with the present invention, an electrical switch is of the type having a pair of opposed stationary contacts and a movable contact which can alternatively snap into contact with the two stationary contacts is provided, that in parallel opposite surfaces of a foil conductor or sheet metal conductor lie in one plane, that a Paar.von opposing stationary contacts are inserted completely in alignment in corresponding slots are formed within the opposing faces that the two contacts are on the edge of the slots are chiselled by means of pressure that has been exerted in a direction perpendicular to the sheet metal conductor or surface conductor, and that the opposing surfaces of the two contacts have been trimmed after a hole has been punched out has been, so that a contact gap in connection with the opposite surfaces of the surface conductor or sheet metal conductor is trained.

The invention is particularly advantageous when used in the the following way-is carried out.

The invention is applicable to an electrical switch of the type in which the conductor unit is exclusive of the a movable contact equipped leaf spring is completely formed by moving from a sheet metal conductor through a Pressing operation is punched out and as a result in

is on one level; the one equipped with a moving contact Leaf spring is inserted around the spring support, which is located at the base of the common clamp, so that they are upward with the spring support as a pivot point and "can move downwards; the terminals of the electrical switch, which in the above-mentioned manner completely off a metal strip is punched out with an adhesive agent or an adhesive on at least one attached by the two segments which form a separately molded switch housing, and after that attachment is the webbing that has been left unpunched for the purpose of temporarily connecting the clamps together, cut away; the top and bottom right-angled edges of the slots that are inside the opposing faces of a sheet metal conductor are beveled by a punch prior to the application of pressure.

The inventive method for producing the electrical Switch according to the invention essentially comprises the steps of making I-shaped holes through a sheet conductor to punch, contact pieces that are essentially I-shaped Holes are compliant to produce by punching out a strip of contact material, the contact pieces under pressure in insert the I-shaped holes, chisel the contacts in both the upward and downward directions, subsequently the I-shaped contact pieces across their center in connection with the adhering portion of the surrounding To perforate sheet metal conductor and thereby to form contact gaps and the opposite surfaces of the resulting to complete pair-wise contacts by re-cutting, which is carried out by means of pressing.

An apparatus for manufacturing electrical switches according to the invention comprises a device comprising a strip electrically conductive material, a press for punching the strip, a pressing tool and a die for

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punch an I-shaped hole in the strip, a device for conveying a strip of contact material in a position directly above 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 that the Insert the contact piece just cut from the strip into the I-shaped hole underneath it, a bearing surface that pushes the Strips of electrically conductive material in one position holds, in which the I-shaped contact piece is caulked subsequent to the 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 part of the surrounding electrically conductive material, means for recutting on the opposite Areas of the resulting contacts separated by a gap and means for punching out the unnecessary portion of the electrically conductive material, so that conductors and terminals are formed.

The term "I-shaped" is used and relates broadly refer to all the forms with which a pair of opposites Contacts can be obtained 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 shaped to correspond to the I-shaped holes are inserted into the holes and hemmed in. Then the I-shaped contact materials across their center in connection with the subsequent or connected parts of the electrically conductive material perforated or perforated to each contact material to divide into two contacts by one between

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these formed contact gap are separated. A leaf spring that has a movable contact at one end is equipped, which is to be used in the contact gap, is immovable in their position, which is not Represents state, held by simply inserting its other end around the stump or attachment of a spring carrier will. Clamps that are held in their fixed relative position by means of a strap that these connects with each other, are attached to a plastic housing with an adhesive agent or an adhesive. After fastening, the webbing is cut off.

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

Fig. 1 is a schematic diagram showing a preferred embodiment illustrates a method for manufacturing electrical switches according to the invention,

Fig. 2 is a plan view illustrating an electrical switch; which is embedded in one of two segments that form a prefabricated plastic housing, wherein the electrical switch has terminals which are connected to one another by a tape, such as it in the block of the strip of successive blocks shown on the far left in FIG. 1 has been obtained, .and with a leaf spring inserted in its position,

Fig. 3 is a side elevation of the electrical switch which is completely is enclosed in a prefabricated plastic housing,

Fig. 4- is a cross-sectional view showing a metal strip with illustrates a punched hole for inserting a piece of silver as a contact material, 4098U / 0493

• - 8th -

Figure 5 is a cross-sectional view illustrating how on the same strip, the top and bottom right-angled edges of the hole beveled under pressure will, '

6 shows the third step of the series of steps illustrated in FIG. 1, in which a piece of silver 15 * punched out of a silver strip 15 and immediately is pressed into the hole 12 previously punched in the strip 11,

7A and B show a Schemsbisch step in which the silver piece 15 'inserted into the hole 12 and immediately exerted on its upper and lower ends Force is hampered,

8A and B schematically show the same step in which the Silver piece 15 'with a greater height in the hole is hemmed in,

9A and B schematically the step in which an elongated Hole 20 that has the silver piece 15 'in the middle crosses and into the adjoining or connected portion of the surrounding electrically conductive material extends, is punched out, so that the silver piece 15 ' is spliced or split in the middle,

10 and 11 are plan views, in which a preferred embodiment of a group of top and bottom, continuous punching tools or dies are illustrated which are used for them in Fig. 1 illustrated workflow

12 is a plan view of a leaf spring F,

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13 is a side view of the leaf spring F,

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

15 and 16 are 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 terminals connected by means of an adhesive will,

17 and 18 are a plan view and a side view, respectively, of a Punching tool that is used to split the piece of silver 15 'and

19 and 20 are a plan view and a side view, respectively, of a Punching tool that is used for the process of STachschuttering is used.

In Fig. 1, the method for manufacturing electrical switches according to the invention is illustrated with the aid of an explanatory diagram. In this method, nine successive presses, each comprising a punch and a die, are operated to perform successive manufacturing steps on a sheet metal strip 11 as it 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 to carry out one manufacturing step at a time in the operational sequence. More specifically, a press equipped with upper and lower dies or pressing tools is operated similar to the ones shown in FIGS block

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or one movement? step at a time for the next Punching stroke moved.

The strip 11, which is made of a copper alloy, is 21 mm wide, 0.8 mm thick and divided into blocks with a unit length of 20 mm - The Roman numerals Ί to X, the one in the drawing below the lower one. Edge of the strip are serial numbers that characterize the production sequence. A streak of silver called that Contact material is used, has a width of 5 »0 mm and the same thickness of 0.8 mm as the strip 11 and is fed with a pitch of 5 mm. The main facility The genes and tools used in this work process are described below. One press and one 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 and required for the pressing operation therefore no representation for their explanation. In the first step, a punching tool 30 and a Die 30 'uses »which are suitable, an I-shaped To punch a hole as shown in FIGS. The third step requires a feed device, the strips 15 of contact material, usually silver on the I-shaped hole. 12 advances in a direction perpendicular to the strip 11, a punching tool or a Die 16 '(Figs. 6 and 11) 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 is used, which is arranged underneath for the contact material 15'j which is pressed into its adjusting ring in the hole in order to to be hemmed in. In the fifth step a punching tool 31 and a die 31 * (Hg. 17 and 18) are used,

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which are capable of punching an elongated hole 20 across the I-shaped contact material 15 'in the middle, as shown in Figs. A punch 32 and a die 32 '(Figs. 19 and 20), the opposite Areas of contact can be used in the sixth step. From the seventh to the new step punching tools and dies are used which serve to punch out unnecessary sections from the strip 11. For the tenth and final step, a conveyor is required that moves the clamps forward with the a belt or webbing connected to a belt for deposition or assembly. The individual manufacturing steps are described below. The first step is the I-shaped hole 12, which is with its upper and lower Ends at locations where the opposite pair of stationary contacts P and P are expected to fall, (Fig. 2), punched out. In the illustrated embodiment jump the top and bottom of the I-shaped hole in ' in the form of "serifs", but these protrusions can be omitted if circumstances so require. At the same time, 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 illustrated in FIG. 4 is. If this cross-section were left unchanged in this form, the piece of silver to be inserted into the hole could become move freely in the vertical., direction. To this movement to prevent, as a result, the upper and lower right-angled edges of the hole by pressing in the second Beveled step. At the same time a hole 14 is punched out in a pattern so that individual ones are separated from one another Terminals are formed.

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In the third step, the silver strip 15, which is in a Is advanced in the direction perpendicular to the strip 11 of electrically conductive material, guided to the punching die 16 ', which is arranged directly above the I-shaped hole 12, as shown in FIG. By means of the punching tool 16 becomes a piece of silver that has a shape that corresponds exactly to the I-shaped hole 12 or only slightly is larger than this, punched out of the silver strip 15 and immediately pushed into the I-shaped hole. Since the hole 12 is held on 'the anvil or the support surface, can the punch 16 can be operated so that there is a slight caulking movement on the silver piece 15 'against the I-shaped Hole 12 created. In this step, a hole 19 is punched out at the same time to create an opening between the clamps A and B. to build.

In the fourth step, the piece of silver 15 ', which during the previous step has been pushed into position, both up and down, either in the in the 7A and B or in the manner shown in FIGS. 8A and B depending on the height of the piece of silver. In Fig. 7 there is illustrated 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 upper and lower sizes become of the silver piece 15 'caulked so that they are expanded to the upper and lower beveled edges of the during cover the I-shaped hole formed in the second step. This caulking is done by making a pair of wedge-shaped Punching tools is moved towards each other to apply pressure along the perimeter. If that as the contact material If the silver piece used has a smaller diameter, the caulking can be carried out by pressing on the Centers of the piece of silver instead of being exercised on the circumference. As a result of the mortising, the silver piece is 15 '

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and the strip 11 is securely connected and at the same time a contact plane or "contact surface" is formed with low electrical resistance As illustrated in Fig. 8. As a result, the silver piece 15 'is deformed to conform to the hole in substantially the same way as if a rivet was in a connected position, ie, from the position shown in FIG Fig. 8A is flattened to the shape shown in Fig. 8B, in which case the third step can be carried out so that the required caulking of the silver piece 15 ^{1 occurs} simultaneously with its insertion into the I-shaped hole, instead of the fourth Step to insert exclusively for the purpose of caulking. Since caulking tends to push the surrounding material outwards, it is inserted before the 'clamps A, B and C carried out to prevent otherwise possible dimensional error in the finished product.

In the fifth step, an elongated hole 20 defining a gap to be inserted between the pair of opposing contacts is punched out, as illustrated in FIGS. 9A and B. This perforation or perforation leads to the formation of a pair of opposing silver ^{contacts P and P 1} (FIG. 2), which are surrounded on all sides except for the punched-out side by the copper alloy material.

In the sixth step, the opposing surfaces of the contacts that cross each other across the gap forming the gap Hole 20 are directed, subjected to a re-cutting treatment to the silver contacts in a final treatment to give a smooth surface and at the same time the Adjust the contact gap to a predetermined size. To

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17, the punching tool 31 ', which is used for punching out the hole 20 across the silver piece 15', has a shape such that 0.08 mm of sand remains on the part 33 for re-cutting. Precise finishing of the silver contacts for a smooth surface and an accurate gap is performed by trimming the edge using the trimming punch 32 (FIGS. 19 and 20). The correct thickness for this edge for recutting is on the order of 10 % of the thickness of the strip 11. The recutting punching tool and the die must not have any play. The two protuberances or stools 35 and 36 at the lower end of the punching tool shown in FIGS. 19 and 20 serve as guides. They slide along holes which are formed by the punching tool shown in FIGS. 17 and 18, and guide the trimming part 34 of the punching tool 32 in the correct manner.

The steps described so far complete the essential part of establishing contact · In the seventh and eighth At step, a hole separating the clips is punched out and becomes the unnecessary portion of the strip removed by punching. The cutting and punching operation performed in the ninth step results in one Three-terminal block as a single part. This block is taken out in the tenth step.

The three terminals A, B, and C that separate the conductor section Form for the leaf spring F are in their fixed relative Position held by means of a solid band D. In the meantime, switch housings are made using a suitable plastic material in mass production made, each of which is provided with three grooves to receive the three clamps A, B and C, one stepped Part 22 for immobilizing the clamps when the clamps

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between the upper and lower segments of the housing, a cavity 23 »which gives 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 actuating rod G, which allows vertical movement of the operating rod. In the preferred embodiment shown, 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 ^{1 of} each housing. However, the two segments E and E ¹ 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 the clamp. A before the switch is firmly enclosed in the housing by means of adhesive. From the practical From a point of view, the operation of enclosing in the housing is advantageously manual executed. The leaf spring. F, the one in Figs. 12 and 13 May have shown particular design is attached by the tongue 26 is slightly bent so that the Gap 27 is widened, and is simply hooked onto the neck or shoulder 25 of the clamp A in this state. Thus can assembly can be carried out easily and the spring of the completed switch exhibits uniform performance on. The leaf spring F can be punched out of a strip of spring material and is therefore for a Suitable for mass production. "As no bending treatment was carried out is a possible change in the spring behavior that could be attributed to a bending operation, locked out. In addition, the manufacturing costs are thereby reduced.

The interconnected terminals A, B and G with the um the spring support 25 inserted leaf spring F are in their '

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Position together with the operating rod G in the corresponding, used in your switch housing formed grooves. In contrast to a conventional switch housing has the groove width of the switch housing according to the invention nothing to do with adjusting the relative position of the clamps. As a result, the grooves with of sufficient width to facilitate the insertion of the clamps. The relative position of these clamps is only through a band D connecting these with each other and then after removing the band by the Maintain the adhesive used to secure the switch to the interior of the housing. This adds to a small one Switch in which the upper and lower segments of the switch housing are permanently bonded to one another by means of an adhesive are attached. 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 to the preferred embodiment described above, in which all terminals are in one switch unit have been punched out of a single piece by pressing, but also in all electrical switches, having a pair of opposing contacts and similar electrical switches.

- patent claims -

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Claims (1)

-M- Claims Electrical switch with a pair of opposed stationary contacts and a moving contact, the alternately snaps into contact contact with the stationary contacts, characterized in that two opposite, contact-holding surfaces of a surface conductor or sheet metal conductor lie in one plane that a pair of opposing stationary contacts is fully inserted into associated slots that are within the opposing one Surfaces are formed, so cfeß the opposite Surfaces of the contacts are essentially aligned with the contact-holding surfaces of the sheet metal conductor that the two Contacts are caulked on the edge of the slot by means of pressure in a direction perpendicular to the sheet metal conductor has been exercised and that the opposing surfaces of the two contacts subsequent to the stamping out of one Hole for the formation of a contact gap in connection with the opposite surfaces of the sheet metal conductor of a re-cutting treatment have been subjected. 2. Switch according to claim 1, characterized in that that the entire conductor is made with the exception of a leaf spring which has a movable contact has been by being punched out of a sheet metal conductor by pressing, and as a result lies in one plane. j>. Switch according to claim 1, characterized in that the leaf spring equipped at one end with a movable contact has a gap at its other end between the end of an inner hole and the front end of the leaf spring tongue which can be inserted around a spring support which is on the base the common clamp is arranged so that the leaf spring moves up and down 4098U / 0493 can move, with the end of the inner hole serving as the fulcrum. 4. Electrical switch according to claim Ϊ, characterized in that the terminals by means of an adhesive Agent or adhesive are attached to at least one of two segments, which is a separately manufactured switch housing form, and that after the completion of the fastening, the tape used for the purpose of temporarily connecting the Terminals have been left unpunched among each other, has been cut off. 5 · "Method of manufacturing an electrical switch, thereby ekenn ζ e i chn e t that I-shaped holes are punched through a surface conductor or sheet metal conductor, that contact pieces, which correspond essentially in shape to the I-shaped holes, by punching out of a strip of contact material be shaped so that the contact pieces are inserted under pressure into the I-shaped holes that the contact pieces both upwards and downwards are caulked that subsequently the I-shaped contact pieces across their center in Connection with the adjoining section of the surrounding sheet metal conductor perforated or perforated to form contact gaps. be perforated and that the opposite surfaces of the resulting contact pair by means of a re-cutting treatment are finally processed, which is carried out by means of pressing. 6. Apparatus for producing an electrical switch, characterized by a device for advancing a strip of electrically conductive material, a press for punching the strip, a pressing tool and a die for punching an I-shaped hole in the strip, a device for conveying a strip Contact material in a position directly above the I-shaped 40981A / 0493 Hole, a punching tool or a die for punching out a contact piece corresponding to the I-shaped hole in the Porra from the strip of contact material, a punching tool which the one just cut out of the strip The contact piece presses into the underlying I-shaped hole, a contact surface that makes the strip electrically holds conductive material in position so that the I-shaped contact piece subsequent to insertion into the A punching tool and a die for punching a hole across the center of the I-shaped contact piece in connection with the adjoining section of the surrounding electrically conductive material, a facility with which to laugh at the opposite! " a single cutting treatment can be carried out on the resulting contacts separated by a gap, and a device which punches away superfluous parts of the electrically conductive material, so that conductors and terminals are formed. 409814/0493 Blank page