CA1115937A - Hand tool for terminal connection of electrical cable to an electrical connector - Google Patents

Abstract

HAND TOOL FOR TERMINAL CONNECTION OF
ELECTRICAL CABLE TO AN ELECTRICAL CONNECTOR
ABSTRACT

This invention relates to a hand tool for assembling an electrical cable to a terminal connector. Using prior art tools, problems arise when an operator exerts indeterminate force on the handle members of the tool during the aforesaid assembly operation, particularly when excess force is exerted by the operator. The present invention provides a hand tool for accommodating different sizes or configurations of terminal connector while avoiding excessive forces. According to the invention the hand tool includes a pair of hand operated opposing jaws for movement toward and away from each other. One of the jaws has a relatively rigid bearing plate defining a bearing surface facing the opposing jaw for engaging the terminal connector. The opposing jaw has a stuffer blade for engaging the cable and driving same into the receptacle portion of the connector. A yieldable backing member is sandwiched between the bearing plate and the one Jaw to provide yielding movement there-between to accommodate variable sized terminal connector and to prevent damage to the electrical cable due to possible excessive pressure being applied when the cable is assembled to the connector. The bearing plate is mounted on the one jaw by a post member securely fixed at one end to the back side of the bearing plate. The post member extends through the backing member and is connected at its other end to the one jaw by lost motion means to accommodate yielding movement between the bearing plate and jaw.

Description

This invention relates to a hand too] ~or assem-blil~g an electrical cable to a terminal connector.
Certain hand tools of the character described, as well as crimping tools in the field o e electrical connectors, commonly include a pair of jaws in a plier-type tool The jaws may have either a pivotal action for cooperation with one another, or a generally parallel action -facilitated by a toggle~type connection. The tool has a pair of handle members pivotally connected to one another and which are pivo-ted by the operator~s hands to effect a connector as-sembly, crimping or other terminal operation through closing movement o- the jaws The handle members are usually spring biased to their open or separated positions and manipulated by the operator to their closed positions against the spring bias It is through forc0 exerted by the operator on the handle member~ that the assembly or -termination is effected.
One common method of terminating electrical cables, for instance, insulation clad cables to terminal connectors, is to insert the cables into receiving slots formed in the connectors and which hold the cables in terminate positions In many instances, the connectors have electrical contact piercing portions or blades which pierce the insulative covering about the cables during assembly or termination of the cables to the connector to establish an electrical con-ductive path therethrough after the assembly operation.
Problems arise when an operator exerts indeterminate Eorce on the handle members oE the tool during the aforesaid assembly operation, particularly when excess force is exerted by the operator, Excessive forces can drive the insulation piercing conductive blades into or through the conductive wire portion or core of the cable causing damage to the cable. This could interEere with the elPctrical ~g~3~

properties of the cable, This problem particularly arises when the electrical COnDeCtOrS to which the cables are ter-minated are of varying sizes for various intended purposes, such as male and female connectors. Without any provision being made ~or the dif~erence in conllector size, the opera-tor can rely only on his ~eel o e the connector to insure that the piercing blades o~ the connector contacts do not damage or overly cut through the conduc-tor core of the cable.
Attempts have been made to provide a hand tool which has adjusting means which can be set to determine the closing ~stance of travel of the jaws o~ the tool depending upon the si~e of the connector which is to be assembled to the appropriate electrical cable, However, with such manu-ally adjustable tools, the tool requires a separate physical action to set the tool eOr each size or configuration of connector, It would be desirable, and this invention is direc~ed, to provide a hand tool of the character described for solving these problems in assembling or terminating electrical cables ior electrical connectors or the like.
An object, therefore, of the present invention is to provide a hand tool for assembling or terminating an electrical cable to a -terminal connector or the like -for accommodating difeerent sizes or configuratiolls of terminal connectors, Another object O-e the invention is -to provide such a hand tool which automatically accommodates difeerent sized terminal connectors, These and other objects are accomplished by pro-viding a hand tool for assembling or terminating an electri-cal cable to a terminal connector or the like which has a receptacle portion for receiving the cable. The tool is in the form of a plier type structure which has a pair of ~2--3t7 handle-operated opposing jaws ~or movement toward and away ~rom each other at adjacent ends o~ handle members which are spring biased to their open or separated posi-tions, The handle operated jaws are manipulated by an operator to their closed positions against the spring bias. The jaws are closed to assemble or terminate the electrical cable -to the terminal conductor through force exerted by the operator on the handle members, A bearing plate is mounted on one of the jaws and has a bearing sur~ace facing the opposing jaw for engaging the terminal connector. The other jaw has a stu~fer portion or blade for engaging the electri-cal cable and driving the cable in-to the receptacle portion of the connector. A resilientl~ yieldable backing member7 in the ~orm o~ a backing pad, is sandwiched between the bearing plate and the one jaw providing yielding movement therebetween to accommodate variable sized terminal connec-tors positioned between the jaws, to prevent damage to the electrical cable due to excess pressure applied by an opera-tor when the cable is assembled to the connector. The beàring plate is moullted on its respective jaw by means of a post type member which is rigidly fixed at one end thereof -to the bearing plate, extends through the yielding backing member, and is connected to the jaw at the other end o~ the post member by los-t motion means in the ~orm o~ a pin and slot connection. The slot is ~ormed in the jaw and extends generally in the direction o~ movement thereo~, and the pin is positioned within the slo-t transversely thereof and ex-tending through the post member. The pin is removable to permit replacement of the bearing plate and/or the yieldable backing member. The stu~fer portio~ or blade on the other jaw is mounted thereon by means of a removable pi]n so tha*
the stu-~fer blade can be removed ~or replacement purposes or for reversal of the s-tu~fer blade, In one form of the invention, the opposing jaws of the hand tool are connected to the handle members o~
the tool by a toggle type connection, and iTl another form of tlle invention7 the jaws ~orm integral extensions o~ the handle members, The invention is particularly directed toward a hand tool for assembling an insulated electrical cable to a terminal conductor or the like which has a receptacle por-tion and an insulation piercing contact for receiving the insulated cable, The tool has a pair of handle operated opposing jaws for movement toward and away from each other.
One of the jaws has means defining a bearing surface ~or engaging the -terminal connector, and the other jaw has a stuffer portion ~or engaging the cable and inserting the cable into the insul~tion piercing contact in the receptacle portion o~ the connector. The tool also has means de~ining a resiliently yieldable backing member in the ~orm of a cushion pad on at least one o~ the jaws between the jaw and the respective bearing surface or the stuffer portioD pro-viding yielding movement therebetween to accommodate vari~
able sized terminal connectors positioned between the jaws and to prevent damage to the electrical cable due to excess pressure applied when the cable is assembled to the con-nector. The cushion pad is -fabricated of a material pro-viding suf~icient back-up to permit the contact to pierce the insulation of the cable but being su-fficiently resilient to prevent the contact from damaging the conductive wire of the cable.
Other objects, features and advantages of -the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.
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Figure 1 is a side elevational view o~ one form O-e the hand tool o~ the present invention;
Figure 2 is an end elevational view taken generally in the direction o~ arrows 2-2 of Figure l;
Figure 3 is a ~ragmented horizontal section taken generally along line 3-3 o~ Figure 3;
Figure 4 is a ~ragmented horizontal section taken generally along line 4-4 o~ Figure l;
Figure 5 is a fragmented horizontal section taken generally along line 5-5 of Figure l;
Figure 6 is a vertical section -taken generally : along line 6-6 o~ Figure l;
: Figure 7 is a side elevational view O:e another ~orm of the hand tool o-f the present inventioll;
Figure 8 is a top plan view o-~ the hand tool o~ :~
Figure 7;
Figure 9 is an end elevational view o~ the hand tool o~ Figure 7, looking toward the le~t o~` the tool shown in Figure 7; and Z0 Figure 10 is an end elevational view looking to-ward the right end o~ the tool shown in Figure 7, Referring to the drawings in greater detail, and speci-fically to the ~orm o~ the inven-tion shown in Figure l;
; . the hand tool o~ the present invention, generally desig-nated 10, is de.signed :eor assembling an electrical cable (not shown) to an appropriate terminal connector (not shown) or the like which has an appropriate receptacle portion eor receiving the cable, The cable is conventional and includes an electrical conducto7~ or wire covered by a coating o~
thermoplastic insul~tive material or the like. Ribbon cables which include a plurality O:e such coated conductors con-nected by a webbing in a planar parallel disposition norm-ally are terminated in an elongated terminal connector which q.~

has a plurality o~ slots extending longitudinally thereo~
defining receptacles ~or receiving the multiple cablesO A
plurality of individual contact members are mounted on the terminal connec-tor in conjunction with each receiving slot and includes conductive piercing blades which cut into or pierce the thermoplastic insulative coating ~or the cables as the cables are stuf~ed into the slots to establish the respective electrical connections. In many instances, the cables must be removed and/or replaced individually for repair or other purposes, and khe hand tool o~ the present invention is designed for assembling an individual cable into an individual receptacle portion of the terminal connector~
Other similar applications o~ the hand tool wil] be apparent ~rom the ~ollowing detailed description.
The hand tool lO includes a pair o~ handle operated opposiDg jaws 12 and 14 (the upper and lower jaws, respectively, shown in Figure 1) which are ~abricated o~
solid rigid material such as steel, or similar alloy materials. ~ , The jaws 12 and 14 are pivotally connected in a toggle arrange-ment to the ends of channel shaped handles 16 aDd 18, respec-ti~ely, by pivot pins 20 and 22, respectively. Each handle 16, 18 has spaced wing-like members 24 disposed at -the inner end thereo~ in a generally parallel spaced dispositio~
sandwiching the jaws 12, 14 therebetween and through which the pivot pins 20, 22 extend. The jaws 12, 14 ex-tend in-wardly beyond the pivot pins 20, 22 between the wings 24 o~
the handles 16, 18 and are connected thereto by a lost motion means, generally designated 26, completing the toggle type connection between the handles and jaws. The lost motion connection 26 ~'or each handle and jaw includes a rear-wardly opening slot 28 ~ormed in the inner ends o:E the jaws 12, 14 and through which pivot pins 30 extend for movement ..~
--6-- ~

lengthwise within -the slots 28 of tha jaws, The pivot pins 30 are fixed at the ends -thereo~ to the respective handles.
As the jaws 12~ 14 open and close in the direction of double headed arrow A (~igure 1) as the handles 16, 18 are operated in the direction o~ double headed arrow B ~Figure 1), the jaws correspondingly move in a toggle type fashion about pivot pins 20, 22 with the difference between the arcua-te paths of movement of the jaws and the handles being accommo-dated by the relative movement of pivot pins 30 within slots 28.
The handles 16, 18 themselves are pivotally con-nected together for opening and closing about double headed pivot pins 32 extending through the pairs of wings 24 at the inner ends of the handles. Each handle 16, 18 is covered by an insulative coating or sleeve 33.
The handles 16, 18 are spring biased to their open ; or separated positions and manipulated by an operator to their closed positions against the spring bias, The spring means includes a pair of elonga~ed coil springs 34 which are secured to their outer ends to tabs 35 on the inside of the handles and at their inner ends to the inner ends of the ja~s 12, 14 within the handles 16, 18, respectively.
A stuf-Per blade 3G is rigidly secured to the in-side o-~ the upper jaw 12 by means of a set screw 38, with the s-tu~fer blade disposed within a slot 40 (Figure 3) ~ormed in the jaw 12. The stuf~er blade 36 has a wa~fle con-figuration 42 along its exposed edge ~acing the jaw 14. The waffled edge 42 engages the outer coating or insulation of an electrical cable during the assembly operation of the hand tool to eliminate longitudinal movement o~ the cable during assembly. The set screw 38 may be loosened to adjust, reverse or replace the stu~fer blade 36.

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~ -7-A bearing plate 44 is secured to the lower jaw 14 and has a flat bearing surface 46 ~acing the stu~er blade 36 in the jaw 12, A resiliently yieldable backing member or cushioning pad 48 is sandwiched between the bearing plate 44 and the jaw 14 providing for yielding movement between the bearing plate and jaw to accommodate variable sized terminal connectors positioned between the jaws 12~ 14 to prevent damage to -the electrical cable due to excessive pressure which might be applied by an operator of thè tool when the cable is assembled or terminated to the connector as further elaborated hereinafter, A lost motion means, generally designated 50, is provided for conDecting the bearing plate 44 to the jaw 14.
More particularly, the lost motion means includes a pair o~
slots 42 formed in the outer or side faces o~ the jaw 14 and extending generall~ in the opening and closing direction of movement of the jaws 12, 14 as shown by the double headed arrow A (Figure 1), A pin 54 extends through the jaw 14 with the opposite ends of the pin disposed within the slots 52, A post like member ~6 is rigidly secured to one end thereof (the top end as viewed in Figure 1) to the underside of the bearing plate 44, extends through a bore 58 in the resiliently yieldable backing member or cushion 48 and through a bore 60 formed in the Jaw 14. The pin 54 e~tends through the post member 56 to mount the bearing plate 44 and the resilient backing member 48 to the jaw 14, This lost motion connection accommod~tes relative movement between the bearing plate 44 and th~ jaw 14 as well as compression and expansion of the resilient member 48 during operation of the tool to assemble or terminate an electrical wire or cable to a terminal connector or the like. The pin 54-preferably is removable, as b~ a press-fit throug~ -the post 3~

member 56 connected to the 'bearing plate 44, to permit replacement of the b~cking member 48 and/or bearing plate 44 and post member 56.
It should be poin-ted out that the resiliently yieldable backing means of the present invention could be appropriately employed between the stuffer blade 36 and jaw 12 to accommodate differences in the sizes and shapes of various connectors, but the present embodiment o-f the back-ing member 48 disposed between the bearing plate 44 and the jaw 14 has proven quite effective.
The yieldable backing member 48 is fabricated of a resilient material depending upon the material of the insulative coating of the particular type o~ electrical.
cable employed with -the hand tool 10 of the present inven-tion, so that the yieldable backing member 48 provides a suf-ficient back-up for the bearing plate 40 whereby the piercing blades of the contact which is mGunted on the ter-mina'l connector can cut through or p~erce the outer insula-tive coating of the cable to esta'blish an electrical con-nection, However, the yieldable backing member 48 should be sufficiently resilient to prevent the piercing b'lades o the contact from cutting through or damaging the conductive wire o~ the cable. In pra~tice, a synthetic rubber material for the backing member 48 of approximately 80 durometer has proven ef:eective for many insula-tion clad cables, to permit the insulative covering o~' the cable to be pierced by the contact blades, but to prevent the wires of the cables to be damaged by the contact piercing blades.
Referring to the form of the invention shown in Figures 7 through 10, a hand tool, generally designated 70 J
is shown to include a pair of handle operated opposing jaws 72 and 74 (the upper and lower jaws, respectively, shown in _~_ 3~

Figure 7), The jaws are ~abricated of solid rigid material, such as steel or similar alloy material.s, and form unitar~
ex-tensions of handle mémbers 76 and 78 ~or -the ~jaws 72 and 74, respec-tively, The jaws 72, 74 and the handle members 76, 78 are pivoted together by a single pivot pin 80 to ~orm a plier-type tool whereby the jaws move toward and away ~rom each other generally in the direction o~ double headed arrow A (Figure 7) and the handle members rnoved toward and away from each other generally in the direction of double headed arrow B (Figure 7~O A coil spring 82 is disposed, under compression, between -the handle members 76 and 78 to bias the hand members and jaws outwardly toward their open or separated positions, A stu~fer blade 84, similar to the stu:f*er blade 36 shown in Figures 1 6, is rigidly secured t,o the inside o~ -the upper jaw 72 by means of a set screw or pin 860 The stuffer blade 84 is disposed within a slot 88 (Figure 9) formed in the jaw 72. The stuPfer blade 84 has a wa~le con-~iguration 90 along its exposed edge facing the jaw 74, As with the stu~er blade 36 shown in Figures 1-6, the wa~led edge engages the outer coating or insulation o~ an electri-cal cable during the assembly or termination operation of the hand tool to eliminate longi-tudinal movement o~ -the cable during assembly. The set screw or pin 86 may be loosened to adjust, reverse, or replace the stuffer blade 84.
A bearing plat,e 92, similar to the bearing pla-te 44 shown in Figures 1-6, is secured to the lower jaw 74 and has a .-~lat bearing surface 94 ~acing the stu~er blade 84 in the jaw 72. A resiliently yieldable backing member or cushioning pad 96, similar to the backing member 48 in Figures 1-6, is sandwiched between the bearing plate 9 and the jaw 74 providing for yielding movement between the bearing plate and jaw to accommodate variable sized terminal 3~

connectors positioned be-tween the jaws to prevent damage to the elec*rical cable due to excessive pressure which might be applied by an operator o~ the -tool when the cable is assembled or terminated to -the connector, as elab~rated in relation to the ~orm o~ the invention shown in Figures 1-6.
A lost motion means similar to that shown in Figures 1-6, is provided for connec-ting the bearing plate 92 to the jaw 74 and includes a pair o~ slots 98 formed in the outer or side ~aces of the jaw 74 and extending generally in the opening and closing direction o~ movement o~ the jaws as shown by -the double headed arrow A (Figure 7).
A pin 100 extends through the Jaw 74 with the opposite ends of the pin disposed within the slots 98, A post-like mem-ber 102 is rigidly secured at one end thereof (the top end as viewed in Figure 7) to the underside o~ the bearing plate 92, extends through a bore 104 in the resiliently backing member or cushion 96, and through a bore 106 formed in the jaw 74. The pin 100 extends through the post member 102 to mount the bearing plate 92 and the resilient backing member 96 to the jaw 74. This lost motion connection accommodates relative movement between the bearing plate 92 and jaw 74 as well as compression and expansion o~ the resilient member 96 during operation of the tool to assemble or terminate an electrical wire or cable to a terminal con-nector or the like. The pin 100 is removable 7 as by a press-fit through the post member 102 to permit replacement o~ the backing member 96 and or bearing plate ~2 anA post member 102~
As mentioned hereinbefore, it should be pointed out that the resiliently yieldable backing means de~ined by the backing member or pad 96 could be approp:ria*ely :`

: \
,. employed between the stuffer blade 84 and the jaw 72, but ~ the present embodiment of the backing member 96 disposed . between the bearing plate 92 and the jaw 74 has proven ~uite effective, In addition, each of the handles 72, 78 is covered by an insulative coating or sleeve 110.
While a particular embodimellt of the present invention has been shown and described~ it is apparent that various changes and modifications may be made, and it is therefore intended i~ -the following claims to cover all such modifications and changes as may fall within the true spirit and scope of this invention.

Claims (21)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A hand tool for assembling an insulated electri-cal cable to a terminal conductor or the like which has a receptacle portion and an insulation piercing contact for re-ceiving the insulated cable, comprising: a pair of handle operated opposing jaws for movement toward and away from each other, one of said jaws having means defining a bearing surface for engaging the terminal connector, and the other jaw having a stuffer portion for engaging the cable and inserting the cable into the insulation piercing contact in the receptacle portion of the connector, and means defining a resiliently yieldable backing member in the form of a cushion pad on at least one of said jaws between the jaw and the respective bearing surface or the stuffer portion providing yielding move-ment therebetween to accommodate variable sized terminal con-nectors positioned between the jaws and to prevent damage to the electrical cable due to excess pressure applied when the cable is assembled to the connector, said cushion pad being fabricated of a material providing sufficient back-up to per-mit the contact to pierce the insulation of the cable but being sufficiently resilient to prevent the contact from damaging the conductive wire of the cable.

2. The hand tool of claim 1 including means for re-movably mounting said yieldable backing member on said one jaw.

3. The hand tool of claim 1 including lost motion means connecting the respective surface means or the stuffer portion to said one jaw to accommodate said yielding movement therebetween.

4. The hand tool of claim 3 wherein said lost motion means comprises a pin and slot construction, the slot extending generally in the direction of movement of said jaws.

5, The hand tool of claim 1 including means on said hand operated jaws for biasing the jaws to an open position.

6. The hand tool of claim 1 wherein said bearing surface means comprises a bearing plate mounted on said one jaw with said bearing surface facing the opposing jaw, and said resiliently yieldable backing member is sandwiched between the bearing plate and said one jaw.

7. The hand tool of claim 6 wherein said bearing plate is mounted to said one jaw by means extending through said yieldable backing member.

8. The hand tool of claim 6 including lost motion means connecting the bearing plate to said one jaw to accommodate yielding movement therebetween.

9. The hand tool of claim 8 wherein said bearing plate is mounted to said one jaw by means extending through said yieldable backing member.

10. The hand tool of claim 9 wherein said last named means is connected to said one jaw by said lost motion means,

11. The hand tool of claim 10 wherein said lost motion means comprises a pin and slot construction, the slot extending generally in the direction of movement of said jaws.

12. The hand tool of claim 11 wherein said pin is selectively removable for placement of said resilient backing member and/or said bearing plate.

13. The hand tool of claim 1 including a pair of handle members for said Jaws, providing a plier-type tool, said jaws being pivotally connected to said handle members by toggle type connections.

14. The hand tool of claim 1 including a pair of handle members for said jaws,providing a plier-type tool, said jaws forming integral extensions of said handle members.

15. The hand tool of claim 1 wherein said cushion pad is fabricated of synthetic rubber, or like material.

16. A hand tool for assembling an insulated electri-cal cable to a terminal connector or the like which has a receptacle portion and an insulation piercing contact for re-ceiving the cable, comprising: a pair of handle operated opposing jaws for movement toward and away from each other, one of said jaws having means defining bearing surface means for engaging the terminal connector and the other jaw having a stuffer portion for engaging the cable and inserting the cable into the insulation piercing contact in the receptacle portion, said bearing surface means comprising a bearing plate mounted on said one jaw with said bearing surface facing the opposing jaw, the bearing plate being fabricated of generally rigid material, a resiliently yieldable backing member in the form of a cushion pad sandwiched between said bearing plate and said one jaw providing yielding movement therebetween to ac-commodate variable sized terminal connectors positioned between the jaws and to prevent damage to the electrical cable due to excess pressure applied when assembling the cable to the con-nector, said cushion pad being fabricated of a material pro-viding sufficient back-up to permit the contact to pierce the insulation of the cable but being sufficiently resilient to prevent the contact from damaging the conductive wire of the cable, said bearing plate and said yieldable backing member being mounted to said one jaw by a post member rigidly secured at one end to said bearing plate and extending through said yieldable backing member, and lost motion means connecting the other end of said post member to said one jaw to accommodate yielding movement of said bearing plate relative to said one jaw.

17. The hand tool of claim 16 wherein said lost motion means comprises a pin and slot construction between said other end of the post member and said one jaw, the slot extending generally in the direction of movement of said jaws.

18. The hand tool of claim 17 wherein said pin is selectively removable for replacement of said resilient backing member and/or said bearing plate.

19. The hand tool of claim 16 including a pair of handle members for said jaws, providing a plier-type tool, said jaws being pivotally connected to said handle members by toggle type connections.

20. The hand tool of claim 16 including a pair of handle members for said jaws, providing a plier-type tool, said jaws forming integral extensions of said handle members.

21. The hand tool of claim 15 wherein said cushion pad is fabricated of synthetic rubber, or like material.