DE2129722A1 - Rotary switch and electrical contact for use in the rotary switch - Google Patents

Description

Munich, June 10, 1971 sch

AMP Incorporated
Eisenhower Boulevard
Harrisburg " Peima., V. St. A.

Rotary switch and electrical contact for use in i

the rotary switch

Priority; June 27th 197Oj Italienj Nrο 26 693 A / 70

The invention relates to a rotary switch and an electrical contact for use therein.

Rotary switches can be used to control the lights and direction indicators of motor vehicles. A known rotary switch includes an abrasive sheet, the looped over a series of contacts, of which M has each a riveted on a circuit board ring clamp, wherein the abrasive sheet is contact with the head one of the rivets, to close a particular circuit.

Another switch has been proposed in which the contacts are received in corresponding holes in the base body of the switch, each contact having a contact part which is channel-shaped in section and protrudes from the associated hole and comes into connection with a sliding contact, as well as a ferrule section for pinching to a conductor ο Each contact element is held in the closed hole by means of lugs at the front end of the contact part ^,!

Bayerische Vereinsbank Munich 820993

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which are formed by means of a die so that the contact element is prevented from being pulled out, and also each contact element has a shoulder at the rear end of the contact part to limit forward movement of the contact element ο Here there is the disadvantage that the work step required to assemble the contacts with A die requires a certain skill on the part of the fitter and is time consuming; it is difficult to make sure that all contacts protrude in the same way beyond the body of the switch, what a constant Contact pressure is required. A second disadvantage is that it is difficult to make contact Remove substitution or review

Another disadvantage is that the sharp surfaces, for example on the approaches, tend to cut into the contact surface of the grinding arm in the reverse grinding direction.

A rotary switch according to the invention is characterized by lugs formed at the ends of the side walls of the channel-shaped contact parts, each end lug bent back around itself and bent away from the other end attachment at the same contact and at the Bend forms a contact surface that is generally perpendicular to the path of travel of the grinding arm.

An embodiment of the invention is described below under Described with reference to the figures. From the figures show:

Figure 1 is a diagrammatic perspective illustration a rotary switch, with parts cut away, and one according to the invention electrical contact)

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FIG. 2 shows a perspective on an enlarged scale Representation of an electrical contact from Figure 1}

FIG. 3 shows a partial section on an enlarged scale along the line III-III from FIG.

The rotary switch 10 has a base plate 11 with a surface 12 and a lower surface 13. A plurality of spaced through holes 14, which are in communication with both surfaces 12 and 13, are provided near the periphery 15 of the base plate 11. Each through hole Ik receives an electrical contact 16, which is made of a resilient conductive material, z. B. made of phosphor bronze. As will be described in detail below, a part of each electrical contact 16 protrudes from the top side 12 of the base plate 11. A wiper arm 17, only a part of which is shown, is arranged to move in an arcuate line and cooperate with the parts of the electrical contacts 16 which protrude upwards from the top 12 of the base plate 11.

Reference is now made specifically to FIG. Each electrical contact l6 has one-piece clamps 21 and 22, which around the core 23 or the insulation 2k of a *

generally designated 25 electrical conductor are crimped, the ferrule 21 being integral with a Contact part 26. The contact part 26 is in section adjacent to the ferrule 21, generally, channel-shaped and has a Base 27 and two upright side walls 28. From the respective side walls 28 extend to those of the ferrule 21 distant ends two arched ^ lugs 29 The two lugs 29 are each arched in opposite directions, so that they converge forwardly from the base 27, butt against each other along a short section 3I, then diverge and finally at bends 32 around itself to ' are bent back and bent away from each other and spring

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form tongues 33, which extend to the side walls 28 and are axially aligned with them »The spring tongues 33 have free ends 2> k»

The lugs 29 are undercut adjacent to the base 27 and form a channel-shaped front stop 351 of FIG is formed by the free edge of the base 27 and short sections of the side walls 28.

According to Figures 1 and 3, each through hole Ik in the base plate 11 is rectangular in cross section and has a first wall 37 »which is radially outward at a distance from a second wall 38, and two approximately radially extending walls 39 (only one of which is shown in Figure 3). The wall 38 is flat, but the wall 37 has a relatively narrow portion 37a (in the radial direction) adjacent the top 12, which is connected to a relatively wide portion 37b adjacent the surface 13 on a shoulder 40 which is on the with the surface 13 related end of the through hole Ik is directed to. The walls 39 each have a switch kl, which is directed towards the end of the hole 14 communicating with the surface 12, so that a relatively narrow section 39a (in the circumferential direction) adjacent to the surface 13 and a relatively wide section 39b adjacent to the Surface 12 is formed.

In order to position an electrical contact 16 in a through hole Ik , the contact is inserted into that end of the hole Ik which communicates with the surface I3, the spring tongue 33 of the contact being compressed by the walls 39 in the section 39a. The contact l6 is further, spring apart in the hole I ^ pushed in until the spring tabs 33 in the inside portion 39b, the free ends of the spring tongues ^ k kl be locked behind shoulders 33 to withdrawal of the con-

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to prevent bar l6. Further forward movement of the electrical contact 16 is prevented by engaging the stops 35 provided on the contact on the shoulder kO on the wall 37. When the electrical contacts 16 are thus positioned in respective through holes 14, the lugs 29 protrude above the surface 12 of the Base plate 11 upwards. As the wiper arm 17 moves along its arcuate path, it engages the bends 32 of the contacts

To remove an electrical contact 16 from the switch 10, the spring tongues 33 of the lugs 29 are compressed so that their free ends Jk are released from the shoulder 4l, whereby the electrical contact 16 can be pulled backwards out of the through hole Ik .

Dirt, such as 01 and dirt, on the contact surface at the free end of the contact 16 is wiped away by the grinding action of the grinding arm, the dirt being pushed into the space between the end approaches or into one of the spaces between the end approaches and the side walls of the hole Ik ·

Patent claims:

109882/1177

Claims (1)

AMP 2925 - £ - Claims Rotary switches with a base plate, over one side of which a rotary switch slide arm moves, with a multiplicity of spaced through holes in the path of travel of the grinding arm, each through hole receives an electrical contact, which has a conductor connection part and a contact part, wherein the contact portion is channel-shaped in section and has a base and side walls and one across the surface the base plate has protruding contact surface and wherein each contact has stops that move forwards and backwards limit the contact in the associated through hole, characterized that each side wall (28) of the contacts (16) has an end projection (29) which is bent backwards and around itself is bent away from the other end projection (29) at the same contact (16) and forms a contact surface at the bend (32), which is generally perpendicular to the path of movement of the grinding arm (17). 2 · - Rotary switch according to claim 1, characterized in that the end section of each end projection (29) is designed as a spring tongue (33) with a free end (3 ^), whereby bending of the spring tongues (33) prevents the insertion of each contact (16) allowed to pass the first shoulders (kl) in the respective through hole (Ik) and engage the free ends (Jk) of the spring tongues (33) on the first shoulders (kl) and prevent the contact from being pulled out to the rear. 3 · Rotary switch according to claim 2, characterized in that that the end projections (29) of each contact (16) are each curved in the opposite sense are that they converge forwardly from the channel base (27), butt against one another along a short section (31) 109882/1177 AMP 2925 - # ~ and then diverge and into the bends (32) of the end lugs pass over 4. Rotary switch according to claim 1 or 2, characterized in that the base (27) of the channel-shaped Contact part of each contact (l6) has a front stop (35) which is attached to a second shoulder (40) engages in the respective hole (l4) and limits forward movement of the contact (l6) in the hole (14). 5 · Electrical contact for use in a rotary switch with a conductor connection part and a contact part, wherein the contact part is channel-shaped in cross section and has a base and side walls and a contact surface for contact with a sliding arm of the rotary switch and stops to limit the forward and backward movement of the Contact in a through hole in the switch, characterized in that each side wall (28) of the contact (l6) has an end projection (29) which is bent backwards around itself and away from the other End shoulder (29) is bent away and forms a contact surface at the bend (32). 6. Electrical contact according to claim 5 »characterized in that each end shoulder (29) around itself is bent back and bent away from the other end projection (29) to form a free end (34) having spring tongue (33) 7 · Electrical contact according to claim 6, characterized in that the end projections (29) each are curved in the opposite sense so that they converge forwardly from the channel base (27), along a short section (3I) abut each other and then diverge and into the bends (32) in the end lugs pass over. 109882/1177 AMP 2925 - # - 80 Electrical contact according to one of claims 5-7 »characterized in that the Base (27) of the channel-shaped contact part a front Has stop (35) which engages a second shoulder (40) in the through hole (l4) in the switch and a forward movement of the contact (l6) in the hole (l4) limited. 109882/1177