Terminal Connector Assembly For Automotive Distributor Contact Breaker

Abstract

A contact breaker assembly including a fixed contact a movable contact and a conductive leaf spring electrically connected to the movable contact and urging the movable contact towards the fixed contact. At its end remote from the movable contact the leaf spring is bent back on itself to define a spring clip having a pair of limbs. A terminal member is engageable between the limbs of the spring clip so as to be electrically and physically connected to the leaf spring, and that region of the terminal which is received between the limbs of the spring clip bears a projection.

Description

This invention relates to contact breaker assemblies for use in internal combustion engine spark ignition systems.

A contact breaker assembly according to the invention includes a fixed contact, a movable contact, a conductive leaf spring electrically connected to the movable contact and urging the movable contact towards the fixed contact, one end of the leaf spring being bent back upon itself to define a spring clip and a terminal member engageable between the limbs of the spring clip so as to be physically and electrically connected to the spring, the terminal having thereon a projection and the spring clip being arranged to receive and grip that region of the terminal which bears the projection.

Conveniently the terminal member is generally rectangular and has the projection disposed generally centrally on one face thereof, there being a conductive lead physically and electrically connected to the terminal member at one edge thereof.

Preferably adjacent the edge of the terminal opposite the lead the terminal is cranked, the terminal being engaged with said spring clip so that the limbs of the clip extend between the cranked portion and the lead and the cranked portion preventing withdrawal of the terminal from the clip in a direction transverse to the limbs of the clip.

Conveniently a second conductive lead is physically and electrically connected to the terminal member at the edge thereof opposite the first mentioned lead.

Preferably the assembly includes a second terminal member, engaged in the spring clip, the second terminal member having therein an aperture which accommodates the projection of the first terminal member, the thickness of the second terminal member being similar to and not less than the height of the projection so that the flexure of the spring clip when gripping the first and second terminal members is similar to that when gripping only the first terminal member.

One example of the invention is illustrated in the accompanying drawings wherein:

FIG. 1 is a plan view of a contact breaker assembly,

FIG. 2 is a sectional view generally on the line 2--2 of part of the arrangement shown in FIG. 1,

FIG. 3 is a plan view of one of the terminals shown in FIG. 1,

FIG. 4 is a side elevational view of the terminal shown in FIG. 3,

FIG. 5 is a plan view of the contact breaker spring shown in FIG. 1,

FIGS. 6, 7 and 8 are plan views respectively of three terminal members, and

FIG. 9 is a plan view of a modification of the terminal member shown in FIG. 7.

Referring to the drawings, the contact breaker assembly includes a conductive angle plate 11 having an integral upstanding tag 12 to which is secured to the fixed contact 13 of the assembly. The movable contact 14 of the assembly is carried by a metal shell 15 secured to an insulating heel member 16 which defines a pair of arms 17 embracing a post 18 upstanding from the plate 11. The arms 17 mount the heel 16 for pivotal movement about the axis of the post 18 so that the movable contact 14 is movable towards and away from the fixed contact 13. A conductive leaf spring 19 is riveted at one end to the metal shell 15, and so is electrically connected to the movable contact 14. At its other end the spring 19 extends within a channel in an insulating abutment member 21 supported on a tongue 22 upstanding from the plate 11. The spring 19 is stressed when engaged in the channel in the member 21, and so urges the heel 16 to pivot about the post 18 to engage the contact 14 with the contact 13. The free end of the spring 19 remote from the heel assembly projects from the channel in the member 21, and is bent back upon itself to define a spring clip 23. In use the contact breaker assembly is mounted within the casing of an ignition distributor adjacent a rotatable cam shaft thereof. The heel member 16 has a cam follower portion 24 which engages the cam surface of the cam shaft and rotation of the cam shaft results in movement of the contact 14 into and out of engagement with the contact 13. The fixed contact 13 is earthed through the angle plate 11 and the casing of the distributor, and one terminal of a capacitor is also earthed through the casing of the distributor. The other terminal of the capacitor is to be connected to the contact 14 as is a low tension terminal provided on the casing of the distributor. The low tension terminal carried by the casing is electrically connected, in use, in the usual manner through the primary winding of an ignition coil to one pole of a battery, the other pole of which is earthed.

The low tension terminal on the casing of the distributor is connected by way of a conductive lead to a conductive terminal member 25. The terminal member 25 is generally rectangular in plan view, (FIG. 3) and is provided with a generally centrally disposed projection 26. Adjacent one edge the terminal member 25 is provided with a deformable tag 27 which is deformed to grip the sheath of the associated conductive lead, the conductive core of the lead being welded to the terminal member with the lead extending parallel with the edge of the terminal member. Adjacent its opposite edge the terminal member is formed with a cranked portion 28 and the distance between the cranked portion and the lead which is secured to the terminal member is substantially equal to the width of the strip forming the clip 23. Thus the terminal member can be engaged between the limbs of the clip 23 with the lead of the terminal member above the clip and the cranked portion 28 thereof below the clip, the lead and the crank portion resisting withdrawal of the terminal member transversely relative to the clip. As shown in the drawings, the terminal member can be provided with a cranked region adjacent the lead, so that the second crank portion aids the lead in resisting movement of the terminal member relative to the clip in one direction.

A second conductive terminal member 29 (FIG. 7) is connected to said other terminal of thc capacitor by way of a conductive lead, the terminal member 29 being substantially flat, and having a centrally disposed aperture 29a. The height of the projection 26 on the terminal member 25 is substantially equal to and not greater than the thickness of the terminal member 29, and the terminal members 25, 29 are engaged in facial contact between the limbs of the clip 23 with the projection 26 accommodated within the aperture 29a of the terminal 29. Movement of the terminal member 29 relative to the terminal member 25 is resisted by engagement of the projection with the walls of the aperture 29a, and as previously described movement of the terminal member 25 transverse to the clip is resisted by the cranked portion 28 and the lead associated with the terminal member 25. Longitudinal movement of the two terminals 25, 29 relative to the clip is resisted in one direction by the closed end of the clip, and in the other direction by an end face of the member 21. Thus in order to readily engage the terminal 25 and the terminal 29 with the clip 23 it is desirable to disengage the end of the spring 19 from the member 21. Thereafter, the terminals can be moved longitudinally relative to the clip between the limbs of the clip.

The provision of separate terminals 25 and 29 for connecting the contact 14 to the low tension terminal on the casing of the distributor and to the capacitor permits replacement of one of the connections without alteration of the other connection. Thus for example should the capacitor prove to be faulty the capacitor can be replaced without replacing the terminal member 25, the lead associated therewith and the low tension terminal on the casing. However, when the distributor is initially being assembled it is convenient to make the electrical connection between the capacitor and the contact 14 and the low tension terminal and the contact 14 by means of a single terminal member. Such a single terminal member is shown in FIG. 6, and is similar to the termainal 25 with the addition of an extension to which the second lead is connected. Thus the terminal includes a central region 31 having thereon a projection 32 and having at opposite sides thereof cranked portions extended to receive respective conductive leads 33, 34. The terminal includes a pair of deformable tags equivalent to the tag 27 of the terminal 25. The region 31 of the terminal is received between the limbs of the clip 23, and since the terminal is provided with a projection 32 equivalent to the projection 26 of the terminal 25 then the clip 23 will be flexed by a similar amount when gripping the terminal shown in FIG. 6 as when gripping the pair of terminal members 25, 29 as shown in FIG. 2. It will be appreciated that should it be required to make a third electrial connection to the contact 14 then the third electrical connection can be made by way of a terminal member identical with the terminal member 29. In such an instance, the projection 32 would be accommodated within the aperture 29a of the terminal member 29.

In an assembly utilising the terminal member shown in FIG. 6, should it become necessary to replace for example the capacitor and the lead 34, then the terminal member can be severed along the line of the cranked portion of the terminal member associated with the lead 34 leaving a terminal member substantially identical with the terminal member 25. Thereafter, a replacement capacitor can be inserted into the assembly the conductive lead of the replacement capacitor carrying a terminal member similar to terminal member 29.

Where two separate terminal members are engaged with the clip 23 it will be appreciated that it is not essential that the terminal member which carries the projection is also the terminal member which is provided with the cranked portion. Thus the terminal member with the projection could be plain other than for the projection 30a as shown at 30 in FIG. 8, and the terminal member with the aperture could have the cranked portion.

The modified terminal member 35 shown in FIG. 9 can replace any of the terminal members of the kind having a hole for receiving the projection of a mating terminal member. The modification consists of the replacement of the hole 29a by an open ended slot 36 and the provision of an planar extension 37. The slot 36 permits easy engagement of the terminal 35 between the limbs of the clip without the need to remove the terminal having the projection from the clip in order to inter-engage the terminals. The extension 37 lies in the channel of the abutment member 21, in use, and so resists disengagement of the terminal 35 from the assembly in the direction in which the slot extends.

Claims

1. A contact breaker assembly, for use in an internal combustion engine spark ignition system, including a fixed contact, a movable contact, a conductive leaf spring electrically connected to said movable contact and urging said movable contact towards said fixed contact, one end of said leaf spring being bent back upon itself to define a spring clip, and a terminal member engaged between the limbs of said spring clip so that the terminal is physically and electrically connected to said spring, said terminal having thereon a projection, and being positioned between said limbs with said limbs gripping between them that portion of the terminal

2. An assembly as claimed in claim 1 wherein said terminal member is generally rectangular and has said projection disposed generally centrally on one face thereof, there being a conductive lead physically and

3. An assembly as claimed in claim 2 wherein the edge of the terminal opposite the lead the terminal is cranked, the terminal being engaged with said spring clip so that the limbs of the clip extend between the cranked portion and the lead and the cranked portion preventing withdrawal of the terminal from the clip in a direction transverse to the limbs of the clip.

4. An assembly as claimed in claim 2 wherein a second conductive lead is physically and electrically connected to the terminal member at the edge

5. An assembly as claimed in claim 3 further including a second terminal member, engaged in said spring clip, the second terminal member having therein an aperture which accommodates the projection of the first terminal member, the thickness of the second terminal member being similar to and not less than the height of the projection so that the flexure of the spring clip when gripping the first and second terminal members is

6. A contact breaker assembly for use in an internal combustion engine spark ignition system, including a fixed contact, a movable contact, a conductive leaf spring electrically connected to said movable contact and urging said movable contact towards said fixed contact, one end of said leaf spring being bent back upon itself to define a spring clip, and a terminal member engaged between the limbs of said spring clip, whereby said terminal is physically and electrically connected to said spring, said terminal member including a first portion bearing a projection, said first portion being gripped between said limbs of said spring clip, and said first terminal member including a second, marginal portion projecting from between said limbs at one side of said clip, and having physically and electrically connected thereto a first conductive lead, and, a second terminal member engaged between the limbs of said spring clip, whereby said second terminal member is physically and electrically connected to said spring, said second terminal member including a first portion having therein an aperture, said first portion of said second terminal member also being gripped between said limbs of said spring clip, with said projection of said first terminal member disposed in said spring, said terminal including a central portion bearing a projection, said central portion being gripped between said limbs of said spring clip, a first marginal portion projecting from between said limbs at one side of said clip, and having physically and electrically connected thereto a first conductive lead, and a second marginal portion projecting from between said limbs, at the opposite side of said clip and having physically and

7. A contact breaker assembly for use in an internal combustion engine spark ignition system, including a fixed contact, a movable contact, a conductive leaf spring electrically connected to said movable contact and urging said movable contact towards said fixed contact, one end of said leaf spring being bent back upon itself to define a spring clip, and a first terminal member engaged between the limbs of said spring clip, whereby said first terminal member is physically and electrically connected to said aperture of said second terminal member, and said second terminal member having a second, marginal portion projecting from between said limbs at one side of said clip, and having physically and electrically connected thereto a second conductive lead, the thickness of said second terminal member being similar to, and not less than the height of said projection of said first terminal member so that the flexure of said spring clip when gripping said first and second terminal members is similar to that when gripping only said first terminal member.