US3852864A

US3852864A - Contact removal tool for electrical connector

Info

Publication number: US3852864A
Application number: US00432748A
Authority: US
Inventors: D Kirk
Original assignee: Litton Systems Inc
Current assignee: Northrop Grumman Guidance and Electronics Co Inc
Priority date: 1974-01-11
Filing date: 1974-01-11
Publication date: 1974-12-10
Anticipated expiration: 1991-12-10

Abstract

An improved removal tool is shown for removing contacts from an insulated housing in which the contacts are mounted to form an electrical connector. The ring-shaped tool is conveniently worn upon a finger of the user for freeing the wearer''s hands and thereby simplifying his or her task. The removal tool includes a shoulder that abuts the insulated housing to locate a tab with respect to the housing. The tab is then inserted to engage a contact latch and allow the removal of that contact.

Description

Kirk, Jr.

[4 Dec. 10, 1974 CONTACT REMOVAL TOOL FOR ELECTRICAL CONNECTOR Primary Examiner-Thomas H. Eager Attorney, Agent, or Firm-M. Michael Carpenter;

- [75] Inventor: ggifilarilld C. Kirk, Jr., .Naugatuck, Alfred R Levine; Alan C Rose 73 Assi nee: Litton S stems Inc. Beverl Hills, I 1 g Cam y y 57 ABSTRACT {22] Filed. Jam 11, 1974 An improved removal tool is shown for removing contacts from an insulated housing in which the PP .2 32,748 contacts are mounted to form an electrical connector.

The ring-shaped tool is conveniently worn upon a tin- [52] US. Cl. 29/203 H ger of the user for freeing the wearers hands and 51 Int. Cl B25b 27/02 hereby Simplifying his 0r task- The removal tool 5 Field of searchm 29 203 H 203 HC 203 HT, includes a shoulder that abuts the il'lSUlfiIEd housing 110 29/203 R locate a tab with respect to the housing. The tab is then inserted to engage a contact latch and allow the [56] References Cited removal of that contact.

UNITED STATES PATENTS 6 Claims, 4 Drawing Figures 3,382,558 5/1968 Lutz et a] 29/2'O3 H g g l PATENIED DEC 10 i974 FIG.2

FIG.3

BACKGROUND OF THE INVENTION- This invention relates to hand tools and, more particularly, to a hand-worn tool for removing electrical contacts from an electrical connector.

It is known in the prior art to provide an electrical connector in the form of a molded insulator into which electrical contacts are inserted and locked by various latching arrangements. Such contacts are formed into complex shapes that may include a spring latch member by a continuous die stamping process. It is also known in the prior art to provide rectangular openings in the side of the insulated housing into which a removal tool may be inserted for releasing the contact locked therein. In these prior art arrangements, the removal tool may take the form of a screwdriver-like device whose tip is ground to provide an extended rectangular portion for insertion into the rectangular slot in the insulated housing. Other less suitable devices have been used, such as a small screwdriver or a sharp pencil point. These devices are not desirable since they often.

overstress the latch formed within the stamped contact which renders that latch useless when the contact is reinserted into the housing. The contacts are in turn connected to suitable wires which are utilized for carrying voltage or current signals to various electrical components attached thereto.

During wiring and maintenanceof the various electrical devices in which the connector shown by example in the present invention is used, it often becomes desirable to rearrange or replace the wiring within the electrical connectors. Hand removal tools used by the prior art required an operator to hold the connector in one hand while manipulating the handheld tool in the other. With two hands thus occupied, a worker often wished he or she had yet another hand to remove the contact and the attached wire from'the connector. The

worker was often forced to place the connector upon a work surface and hold the connector firmly against the surface with a few fingers while using the remaining fingers available to manipulate the hand-held tool. This would free a hand to remove the contact and its attached wire.

SUMMARY OF THE INVENTION The deficiencies cited above are overcome by the present invention through the use of a ring-shaped removal tool which can be conveniently worn on the users finger. The unique arrangement of the removal tool allows the wearer to hold the connector in one hand while wearing the tool on a finger of the same hand. The removal tool is placed in juxtaposition with the insulated housing of the connector whereby a shoulder locates the tool and aligns a tab for easy insertion into a rectangular opening in the housing. The shoulder and tab arrangement of the ring-shaped removal tool holds the tool in position on the housing for freeing the wearers second hand to remove or replace a contact and wire attached thereto.

Accordingly, an object of the present invention is to provide an improved hand-worn tool.

Another object of the invention is to provide an improved hand tool which may be worn rather than held by the user for freeing both of the users hand to conduct his or her work more efiiciently.

A further object accomplished by the present invention is to provide a ring-shaped tool which cooperates with an electrical connector such that the tool and connector are easily held by one hand of a user to provide an improved working arrangement.

Other objects and advantages of the present invention will become apparent to those skilled in the art after careful consideration of the specification and drawings, wherein:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 isa perspective view showing the contact removal tool of the present invention and an electrical connector with which it is used.

FIG. 2 is a perspective view showinga typical contact which may be used in combination with the removal tool of the present invention.

FIG. 3 is a cross-sectional view showing a contact removal tool and its interaction with an electrical connector.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, FIG. 1 illustrates an electrical connector 10 including a connector housing 12 formed from a suitable electrical insulating material which may be easily molded, such as polycarbonate. In the embodiment illustrated, the housing 12 has a generally rectangular cross section with upper and

lower surfaces

14 and 16, respectively. Extending between the upper and lower surfaces are a plurality of contact receiving chambers 18 having a generally rectangular configuration when viewed as a cross section through the insulating housing l2 and having a generally square cross section when viewed from either the upper or

lower surfaces

14 or 16.

The square cross section of the contact receiving chambers in the upper surface 14 is arranged to receive an electrical contact 20. Electrical contact 20 includes a pin receiving section 22, shown in the upper portion of FIG. 2; an insulation crimp section 24; and a wire crimp section 26. The insulation crimp and

wire crimp sections

24 and 26 are shown in their configuration prior to being crimped upon an insulated wire 28, see FIG. 1. I

The pin receiving section 22 of contact 20 is formed as a box-shaped arrangement to receive a suitable electric contact, such as a wire-wrap pin having a square cross section with a dimension of 0.025 inches per side. Two opposing sides of the box-shaped pin receiving section 22 are relieved to form inwardly directed spring tangs 30 which wipe against the contact pins inserted therein. A third side of the box-shaped pin receiving section is also relieved to form an outwardly directed spring latch 32. g

After the insulated wire 28 has been crimped upon the-electrical contact 20, the contact may be inserted through the upper surface 14 into the contact receiving chamber l8.One side wall of the contact receiving chamber 18 is provided with a rectangular relief 34 which communicates with the outer surface of the insulating housing 12. The rectangular relief provides an opening into which the spring latch 32 locks as it is inserted into the contact receiving chamber 18.

Referring now to FIG. 3, the cross section of the insulating housing 12 is shown with the contact inserted therein. It will be noted that the spring latch 32 pops into the relief 34 such that the outermost end abuts against the side wall of relief 34. The contact receiving chamber 18 within housing 12 is provided, at its lower portion, with a shoulder 36 which restrains the forward motion of the contact 20. When the electrical contact 20 is in its appropriate position, its removal from the housing 12 will be prevented by the interaction of the spring latch 32 and relief 34. The lower surface of contact receiving chamber 18 communicates with the lower surface 16 of housing 12 through a square aperture 38 whose outer surface is tapered for conveniently receiving square wire-wrap pins or other electrical contacts, not shown.

After insertion of an electrical contact 20 and attached wire 28 into the contact receiving chamber 18, it often becomes desirable to remove the wire 28 and contact 20 for replacement or relocation. For this purpose, the present invention provides a hand-worn contact removal tool 40 shown in FIGS. 1 and 4. The removal tool may be produced by machining; however, in the preferred embodiment, it is molded from a nonconductive plastic, such as a glass-filled polycarbonate. The removal tool 40 is generally toroidal or ringshaped, having parallel inner and

outer surfaces

42 and 44, when viewed from the perspective of the wearer. The removal tool 40 is relieved along its central axis with a conical aperture 46 which tapers inwardly along the axis from the inner surface 42 to the outer surface 44. The tapered aperture allows the removal tool to be worn comfortably on any finger of any user. The taper terminates at the outer surface 44 in a radius 48.

Below the circular perimeter of the inner surface 42, 3

the contact removal tool is relieved at four relief segmentsSO equally spaced about the tool perimeter.

Relief segments form a shoulder 52 just below .the'

inner surface 42 and cause the perimeter of the outer surface 44 to be generally square shaped. Extending from the center of each side of the generally squareshaped outer surface 44 is a latch depressing tab 54 having a rectangular cross section for interfacing with the rectangularly configurated relief 34. The protrusion of the tab 54 from the flat surface formed by relief segments 50 forms an inwardly directed shoulder 56 located at a pre-determined distance from shoulder 52.

Referring again to FIG. 3, it will be seen that the contact removal tool may be conveniently worn upon the index finger, for example, of the user. Should the user wish to remove the contact 20 from the housing 12, he or she simply grips the housing 12 between the thumb and index finger. As the contact removal tool is worn in a ring-like manner about the tip of the w'earers index finger, the tool becomes an extension of the wearer's index finger which grips the housing 12' the

shoulders

52 and 56 with the relief 34 and lower surface 16 of housing 12 tends to lock the removal tool into the desired position. It is then a simple motion for the user of the removal tool to squeeze the tool 40 and housing 12 between his index finger and thumb. This squeezing motion depresses the spring latch 32 for freeing its outermost end from the relief 34. The spring latch cannot be overstressed due to the flat surface of segment 50 which acts to limit the distance tab 54 may be inserted. The users other hand is now free to remove the wire 28 and contact 20 from the contact receiving chamber 18. If desired, the removed wire 28 may be simply reinserted into another chamber 18 or replaced.

It will be understood that the preferred embodiment of the contact removal tool described herein may be modified in various degrees. Further, the electrical connector 10 formed by housing 12 and contacts 20 is but one arrangement of several possibilities which may be utilized in combination with the contact removal tool. In the preferred embodiment, one important feature is the location of the rectangular relief 34 within housing 12 which matches the space between the shoulder 52 and shoulder 56 formed upon tab 54. Still further modifications and variations of the present invention will become apparent to those skilled in the art after consideration of the invention described herein.

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

1. An electrical connector system comprising:

an electrical contact having an extending latch arm;

a housing having first and second outer surfaces arranged at right angles to one another, said housing having a contact receiving chamber extending from said first surface into said housing and a latch receiving opening communicating between said chamber and said second surface of said housing;

' and a contact removal tool having first and second surfaces including a tab portion extending from said second surface of said tool into said latch receiving opening in said second surface of said housing for urging said contact latch arm from said latch receiving opening when said first surface of said contact removal tool engages said first surface of said housing.

2. An electrical connector system as claimed in claim wherein: I g

said first surface of said contact removal tool is a shoulder located at right angles to said second surface from which said tab portion extends at a predetermined distance from said shoulder; and v said opening in said second surface of said housing is located at a distance from said first surface thereof equal to said pre-determined distance for retaining said contact removal tool in its proper position once that position is established.

3. A hand tool for removing electrical contacts from a housing, wherein each contact includes a spring latch which engages a latching shoulder formed by an opening in said housing, the improvement comprising:

said tool having a first reference surface for locating said tool against said housing;

said tool having an extending protrusion located from said first reference surface for extension into said opening to engage and displace said spring latch from said latching shoulder in said housing;

whereby said electrical contact may be removed from said housing upon displacement of said spring latch by said extending protrusion.

4. A hand tool as claimed in claim 3, wherein:

said hand tool is ring shaped and said first reference surface is a shoulder perpendicular to the longitudinal axis of said ring-shaped tool;

said extending protrusion extends perpendicularly to said longitudinal axis having a second shoulder parallel to said first-mentioned shoulder located a predetermined distance therefrom; and

said housing includes a surface located at a distance from said latching shoulder formed by said opening in said housing which equals said pre-determined distance on said hand tool;

whereby said first-mentioned shoulder on said hand tool engages said housing surface as said extending protrusion is inserted into said housing opening for locking said hand tool in its proper work position while removing said electrical contact.

5. A hand tool as claimed in claim 4, wherein:

said ring-shaped hand tool has a tapered opening passing through its longitudinal axis to enable said tool to be worn on any finger of any user.

6. In a system for removably retaining a first device within a second device wherein said first device includes a latch mechanism for engaging a latch receiving opening in said second device to retain said first device therein, the improvement comprising:

a hand-worn removal tool having a first reference surface for engaging said second device and an extended tab portion for engaging said latch mechanism of said first device through said latch receiving opening in said second device when said first reference surface of said tool engages said second device for generally securing said hand-worn removal tool against said second device thus freeing the wearers hands for other work including removal of said first device.

Claims

1. An electrical connector system comprising: an electrical contact having an extending latch arm; a housing having first and second outer surfaces arranged at right angles to one another, said housing having a contact receiving chamber extending from said first surface into said housing and a latch receiving opening communicating between said chamber and said second surface of said housing; and a contact removal tool having first and second surfaces including a tab portion extending from said second surface of said tool into said latch receiving opening in said second surface of said housing for urging said contact latch arm from said latch receiving opening when said first surface of said contact removal tool engages said first surface of said housing.

2. An electrical connector system as claimed in claim 1, wherein: said first surface of said contact removal tool is a shoulder located at right angles to said second surface from which said tab portion extends at a pre-determined distance from said shoulder; and said opening in said second surface of said housing is located at a distance from said first surface thereof equal to said pre-determined distance for retaining said contact removal tool in its proper position once that position is established.

4. A hand tool as claimed in claim 3, wherein: said hand tool is ring shaped and said first reference surface is a shoulder perpendicular to the longitudinal axis of said ring-shaped tool; said extending protrusion extends perpendicularly to said longitudinal axis having a second shoulder parallel to said first-mentioned shoulder located a pre-determined distance therefrom; and said housing includes a surface located at a distance from said latching shoulder formed by said opening in said housing which equals said pre-determined distance on said hand tool; whereby said first-mentioned shoulder on said hand tool engages said housing surface as said extending protrusion is inserted into said housing opening for locking said hand tool in its proper work position while removing said electrical contact.

5. A hand tool as claimed in claim 4, wherein: said ring-shaped hand tool has a tapered opening passing through its longitudinal axis to enable said tool to be worn on any finger of any user.

6. In a system for removably retaining a first device within a second device wherein said first device includes a latch mechanism for engaging a latch receiving opening in said second device to retain said first device therein, the improvement comprising: a hand-worn removal tool having a first reference surface for engaging said second device and an extended tab portion for engaging said latch mechanism of said first device through said latch receiving opening in said second device when said first reference surface of said tool engages said second device for generally securing said hand-worn removal tool against said second device thus freeing the wearer''s hands for other work including removal of said first device.