DE2452305A1 - LEAD FRAME FOR A SWITCHING DEVICE AND PROCESS FOR ITS MANUFACTURING - Google Patents

Description

PATENT LAWYERS

Dipl-Phye. W. KALKOFF

MONKS 71 (Solin)
Franz-Hals-Strasse 21
Tel. (0811) 796213

AMP 3425 Munich, October 22, 1974

NS

AMP Incorporated
Eisenhower Boulevard Harrisburg, Pa. (V. St. A.)

Lead frame for a switching device and its method of manufacture

Priority: Nov. 9, 1973; V.St.A. No. 414 464

The invention relates to switching devices, particularly lead frames used in their manufacture.

GB-PS 1 266 817 describes a lead frame for a Protective tube contact unit in the form of a 14-pin dual-in-line housing. The lead frame is made of sheet metal punched, has two spaced end strips and two spaced side strips arranged substantially in a square and keep the supply lines at a distance from each other. The first ends of the leads are used as connecting pins of the housing formed, and the other lead ends are designed as contact sections for circuit parts located in the housing, including a protective tube contact. The contact sections are all stationary, as the protective tube contact itself carries a movable switch contact.

509820/0763

Bayerische Vereinsbank Munich 823101 Postscheck 54782

The invention is characterized in that the lead frame is bent into a channel shape, the two side strips running along two sides of the channel and the contact arms and intermediate portions of the two end strips extend across the channel floor, and that the end strips so are deformed that the side strips are shifted closer to each other and at least two of the contact arms to each other overlap.

This means that all switching contacts, including the movable contacts, can be built into the lead frame itself which eliminates the need for a protective tube contact.

The invention is explained in more detail below with reference to the drawing. Show it;

Fig. 1 is an exploded view of an electromechanical relay;

2 shows a view of a stamped blank of a contact lead frame for use in the relay of Figure 1;

FIG. 3 is a perspective view of a lead frame after molding from the blank according to FIG. 2 and after removing the carrier strips;

FIG. 4 partial perspective views of the supply line and frame in successive manufacturing phases; FIG. and

FIG. 6 shows a cross section through the fully assembled relay according to FIG. 1.

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An electromechanical relay has a base member 10 and a cover member 12, which together form a housing, two units each with an electromagnet 14 and an armature 16 and a lead frame 18. FIG. 1 shows only one electromagnet 14 and an armature 16; Of course, however, a second unit consisting of an electromagnet and armature would be χ
arranged first unit.

Anchor existing unit offset by 180 to the right of the

The base member 10 is designed as a plastic box with two compartments 20 which are separated by a wall 24; each Compartment is intended to hold an electromagnet and an armature unit. Another side wall of each compartment is slightly formed, as can be seen at 26. On this side wall there is a vertical elongated one square post 28 formed integrally with the side wall and extending upward from the bottom of the compartment (Fig. 6). The surface 30 of the spigot 28, along with the surfaces on the end and center walls a bracket for the precise definition of an electromagnet armature unit.

The outer surfaces of the side walls each have eight channels 32, accommodate the portions of the lead frame 18, as will be explained. The four upper corners of the base link 10 extend beyond the surfaces of the side walls to provide clearance between the lead frames and the cover member 12.

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Each electromagnet has a coil 40, windings 34, one U-shaped metallic core 42 and a pair of coil contacts 44. The armature unit consists of an armature 46 and a Carrier, cam and swivel device, which is simply referred to as swivel unit 48 in the following »

The U-shaped metallic core 42, which consists of a kqpüanaren Metal strips, e.g. B. remunerated HYPEE-49, has a pivot leg 50, a bracket 52 and an actuation leg 54. The surface of the pivot leg is beveled on one side to form a pivot edge 56. The upper portion of the leg 54 is in the lateral Direction expanded to form a wider contact area 58.

The pivot unit 48 is made of nylon (TM) or the like Molded insulating material. At the rear of the pivot assembly, pivot pins 66 protrude from each side wall. Two damping lugs 68 rise on the surface of the swivel unit and run along each edge. It's closed note that the highest point of the lugs is at the front of the trunnions (as seen from the viewer), d. H. the lugs are in relation to the trunnions Forward offset A cam member 70 is on the leading edge the swivel unit and runs parallel to it, The underside of the swivel unit is cut out for receiving the armature 46 as shown in FIG are attached to each other by glue.

The spool 40 is a unit molded from glass filled nylon. It has three distinctive features, namely an upper flange 74, a lower flange 76 and a hollow one

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AMP 3425 - 5 - 245 /: Jüb

square conductor receiving bracket 78 connecting both flanges. The inner surfaces of both flanges are flat and parallel to each other.

The outer surface of the upper flange 74 is delimited on the sides by side walls 80. An inward one Slot 82 is provided in each side wall. A front section 83 the surface is beveled downwards and outwards. At the leading edge and with a gap between the both side walls is a pair of edgewise preloading pins 84 arranged.

One end of the windings 34 is wound around each contact 44 and secured to it by soldering or otherwise. Preferably, after arranging the coil in a compartment 20 placed on the spool.

The lead frame 18 is made of a plate or a Punched and shaped tape of electrically conductive material, e.g. B. made of phosphor bronze, and the tape is preferred gold-plated along the narrow strip that will later form the contact points. First there is a punching process carried out to produce a continuous strip of diecuts, one of which is shown in FIG.

According to FIG. 3, the die cut, which is shaped like the others Lead frame is designated at 18, an upper side strip 80, a lower side strip 81, a left end strip 82 and a right end strip 83. Within the surrounding strips are sixteen contact members 84 provided. Eight of the contact members 84 are integral with the side strip 80 and stand therefrom in front, and the other eight contact members are with the side strip 81 in one piece and stand from this to inrnr? before.

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AMP 3425 - 6 -

The sixteen contact members are arranged in two sets, each of which is the precursor of a double-pole changeover contact, is two damping arms and two coil contact arms. One such sentence is on the right and one on the left the dashed line 104 dividing the frame. It should be noted that that the sets of contact members are identical, but are arranged offset from one another by 180 °, as this is common in relays with double-pole changeover contacts. Since the sentences are identical, only the one on the right will be used The sentence below explains although the corresponding parts in the other sentence have the same reference numerals.

The die cut 18 then becomes the shape of FIG. 3 bent. Each contact member 84 has a leg which is formed from a pin 106 and a holding section 108. The pin 106 is that part of the relay that plugs into spaced holes in a printed circuit board (not shown) is used and makes electrical contact with the cable runs of the plate.

The junction between the pin 106 and the retaining portion 108 forms a downward shoulder 110 that secures an assembled relay in a given Allows clearance above the surface of the printed circuit board.

The retaining portion 108 lies in a groove 32 of the base member 10 and is preferably secured therein with epoxy resin. Everyone Retaining portion 108 has a necked in portion 112 that allows more epoxy to collect at this point, This results in an additional adhesive bracket for the leg on the base link.

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AMP 3425 - 7 -

Each contact member 84 also has an arm or set of arms on the other opposite the leg End of the contact member. With reference to FIGS. 3 and 4, it is again pointed out that each "set" of eight Eontakt members consists, with four protruding to the one and four to the opposite side inward.

Referring to the right sentence, it can be seen that each of the two outer arms that were originally connected to strip 81 have two individual branches. The outermost branches are the coil contact leads 114, which are bent downward so that they run essentially parallel to the leg. In the finished device, these contact leads 114 act against coil contacts 44 and form electrical contact with them. These two connection lines in each set provide the electrical path from the electromagnet to the printed circuit board. The innermost branches are damping arms 116 which are bent downwards from the horizontal and slide over the lugs 68 (FIG. 6). They have two functions. Firstly, they prevent "bouncing ¹ · of the armature, that is, without the anchor assembly would swing after the de-energizing the coil. This bouncing can be a movement of the cam member of the swivel unit have the effect of causing the movable contact is moved away from the normally closed contact. For the second biases when the coil is not energized, the arm 116 advances the armature unit downward to the front portion 83 of the coil 40. This also prevents inadvertent movement of the movable contact arm.

The two inner arms 118, i. H. the arms lying between the leads 114 and the arms 116 are movable contact or switch arms that are designed to be mirror images of one another. Near the inner end of each arm 118 is the

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AMP 3425 - 8 -

Arm divided into two fingers. The outermost finger 120 is offset and downward with respect to the arm proper moved and serves as a movable working contact.

The innermost finger 122 is a continuation of the actual arm and serves as a movable break contact 122.

On the side opposite the named arms, four stationary contact arms are provided which originally protrude inward from the side strip 80. The outermost arms are stationary working contacts 124, and the innermost ones Arms are stationary break contacts 126. When installed in the relay, the stationary contacts 124 are on the preload pins 84 at. Due to their height, these preload pins deflect the arms back into a horizontal position, as a result of which the arms are biased with a force applied to the movable contact 120 during operation of the relay works.

Referring to Figs. 4 and 5, the method by which some of the contact members in such Positions are brought that they are above or between other contact members.

Fig. 4 shows a portion of the lead frame 18 after it has been formed into a U-shape. It should be noted that the movable Contacts 120 and 122 do not rest on the stationary contacts 12 and 126, but are spaced apart from them. To the Placing these contacts between or on top of one another is a compression or displacement step on the carrier end strips 83 carried out. A central portion of each end strip is upset at 128 (Fig. 5). It can be seen that that

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Compress the width between sides 80 and 81 of the lead frame and causes the fixed and movable contacts to overlap each other in a desired manner. The correct arrangement is such that the movable contact 120 is below the stationary contact 124 and the movable contact 122 is above the stationary contact 126.

The electromagnet 14 is now inserted into a compartment 20 and secured therein, preferably with adhesive. According to FIG. 6 the bracket 52 and the lower flange 76 are supported on the floor 132 of the compartment, and the upper flange 74 lies on the pin 28.

The armature unit 16 is now arranged on the electromagnet 14, the pegs 66 lying in slots 82. The anchor 46 lies on top of the leg 50 of the metal core.

After a further electromagnet 14 and an armature unit 16 are arranged in the same way in the adjacent compartment 20, the U-shaped lead frame 18 with the attached side and end support strips 80-83 onto the base member 10 placed so that the holding portions 108 of the contact members fit into channels 32 and the arms with the exception of the contact leads 114 of the contact members are open Bridge compartments 20. The damping arms 116 rest on lugs 68, - tension the anchor unit 16 downwards in this way (FIG. 6), that the armature 46 rests on the section 83 which is tapered towards the front. The movable contacts 122 are over the Fixed contacts 126, while the movable contacts 120 are spaced below the fixed contacts 124.

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AMP 3425 - 10 -

After attaching the lead frame to the base link 10, the cover member 12 without its cover 134 is pushed down over the base member 10 and attached thereto by adhesive secured. Unnecessary parts of the lead frame, d. H. the end strips 82, 83 and those connecting the contact members 84 Portions of the side strips 80, 81 are severed so that the contact members 84 electrically from one another are separated. The relay is now for checking and, if necessary, for adjusting the movable contact arms through the openings 136 ready. After successful testing, the lids are placed on the cover member and secured to it with glue.

The relay described above forms a current path through the movable contact arms and the stationary contacts without coil energization by the normally closed contacts. When the coil is energized, the armature is drawn to the contact surface 58 on the metal core by the magnetic force. While the armature unit is pivoted, the cam member 70 rests against the movable contact arms and lifts them so that the electrical contact between the fixed contacts 126 and the movable contacts 122 is interrupted and the electrical contact between the fixed contact 124 and the movable contact 120 is established . When the coil is de-energized, the armature unit is pivoted back into the position shown in FIG. 5 by the prestressing force of the damping arms 116.

Patent claims;

509820/0763

Claims (2)

AMP 3425 - 11 - Patent claims ■ 1.1 lead frame for a switching device, which is stamped from ^ - * sheet metal, with a pair of spaced end strips which are integrally connected to a pair of spaced apart side strips, with a first plurality of contact members which are made in one piece with one of the side strips and are located in the extending substantially perpendicular thereto, and a second plurality of contact members integral with the other side strip and extending substantially perpendicular thereto, both sets of contact members having contact arms at their adjacent ends and pins at their distal ends , characterized in that the supply frame (18) is bent into a channel shape, wherein the two side strips (80, 81) each run along two sides of the channel and the contact arms (118) and intermediate portions of the two end strips (82, 83) extend across the channel floor, and that the end strips (82, 83) are deformed so that the side strips (80, 81) are displaced closer to one another and at least two of the contact arms (118) overlap one another. 2. lead frame according to claim 1, characterized in that that each end strip (82, 83) at both junctions (128) of the intermediate section with the rest of the Binding strip (82, 83) is bent inward. 509 8 20/0763 AMP ₃₄₂₅ A method of manufacturing a lead frame for a switching device, wherein a lead frame blank is stamped from sheet metal and comprises: a pair of spaced end strips integrally connected to a pair of spaced apart side strips, a first plurality of contact members which are integrally formed with one of the side strips and extending substantially perpendicular thereto, and a second plurality of contact members integral with the other side strip and extending substantially perpendicular thereto, both sets of contact members having contact arms at their adjacent ends and contact arms at their distal ends Pins are formed,
characterized by post-stamping forming the blank (18) into a channel shape by bending the end strips (82, 83) at two spaced apart locations and bending the contact members (84) at the junctions of the contact arms (118) and the pins (106), see above that the contact arms (118) and intermediate portions of the end strips (82, 83) extend across the channel floor; and deforming the end strips (82, 83) such that the side strips (80, 81) are displaced closer together and cause at least two of the contact arms (118) to overlap. 509820/0763