US3197849A

US3197849A - Tool for inserting and extracting removable electrical contacts

Info

Publication number: US3197849A
Application number: US341605A
Authority: US
Inventors: Johnson George Stanford
Original assignee: Deutsche ITT Industries GmbH
Current assignee: TDK Micronas GmbH; International Telephone and Telegraph Corp
Priority date: 1964-01-31
Filing date: 1964-01-31
Publication date: 1965-08-03
Anticipated expiration: 1982-08-03

Description

TOOL FOR INSERTING AND EXTRACTING REMOVABLE ELECTRICAL CONTACTS Filed Jan. 51. 1964 Aug. 3, 1965 G- s. JOHNSON 3 Sheets-Sheet 1 INVENTOR. 650265 574/16 0190 fimusm/ 3, 1965 G. s. JOHNSON 3,197,849

TOOL FOR INSERTING AND EXTRACTING REMOVABLE ELECTRICAL CONTACTS Filed Jan. 51, 1964 5 Sheets-Sheet 3 INVENTOR. Gaoea Jrm/Faea Ll/M/SOA/ Wm WM 147- TOEA/EKS.

United States Patent 0 3,197,849 TQOL FOR ENSERTING AND EXTRACTING REMUVABLE ELECTRICAL CONTACTS George Stanford Johnson, Canoga Park, Califi, assignor,

by mesne assignments, to International Telephone and Telegraph Corporation, New York, N.Y., a corporation of Maryland I Filed Jan. 31, 1964, Ser. No. 341,605 14- (llaims. (Cl. 29-203) This invention relates to a spaghetti type of tool adapted for inserting and extracting removable electrical contacts in an electrical connector. An example of its utility is for shifting a spring locking member to move it clear of a shoulder on a contact member to free the latter for withdrawal.

Further, the invention relates to a tool which provides supplemental electrical insulation, sturdy support and protective sheathing for wire conductors Where they are connected to electrical contact members in the connector, the tool embodying structure which retains the tool in immediate association with the electrical connector, thus insuring that the tool will be continuously available for use in the removal and replacement of contact members in the connector. The present tool is an improvement over the tool disclosed in my US. Patent for Contact Extraction and Insertion Tool, No. 3,110,093 granted November 12, 1963. I

In'more detail, it is an object of this invention to provide a tool for inserting and extracting the contact members of an electrical connector which tool embodies interference fit retention means for removably securing the tool in the bore of the insulator block in which the contact is lodged, so that the tool is always available for use.

Another object of this invention is to provide a tool for inserting and extracting a contact member in an electrical connector wherein the tool provides a support and protective sheathing for the electrical conductor attached to the contact member, the tool'being of a size and shape making it feasible to install and retain a tool on each of a plurality of conductors leading to a connector.

Another object of this invention is to provide a disassembling and assembling tool of the character described which has the required axial rigidity to perform its function in inserting and extracting contact members and yet has the required diametrical (lateral) flexibility to be deformed for an interference fit in an insulation block of an electrical connector wherein contact members are positioned.

Another object of this invention is to provide a disassembling and assembling tool of the character described which embodies stop means to prevent an inadvertent actuation of the tool.

These and other objects and advantages of the invention obtained will be readily apparent from a consideration of the following description when taken in conjunction with the drawings in which:

7 FIGURE 1 is a perspective view of an electrical connector showing a plurality of the tools of this invention mounted on the conductors leading into the connector.

FIGURE 2 is a perspective view of one embodiment of the tool of this invention.

FIGURE 3 is an enlarged cross-sectional view taken along line 33 of FIGURE 1 showing a plurality of tools mounted in an insulation block of an electrical connector.

FIGURE 4 is a cross-sectional view of an insulation block with an electrical contact member mounted therein, showing the tool of this invention disposed on an elec trical conductor outside the insulation block.

FIGURES 5, 6 and 7 are cross-sectional views similar to FIGURE 4 showing the sequence of operation for the tool as it is advanced into the insulation block from the rear for the removal of an electrical contact member.

FlGURE 8 is a sectional view taken along line 88 of FIGURE 6.

FIGURE 9 is a perspective view showing a second embodiment of the tool, this form being continuously cylindrical without any slit.

FIGURE 10 is a perspective view showing a third embodiment of the tool.

FIGURE 11 is a perspective view showing a fourth embodiment.

FIGURE 12 is a perspective view showing a fifth embodiment.

FIGURE 13 is a perspective view showing a sixth embodiment.

FIGURE 14 is a perspective view showing a seventh embodiment.

Referring to the drawings, the tool is generally designated by the numeral 10. It has a generally elongated cylindrical configuration and is provided with an internal bore 11 which extends the entire axial length of the tool. The bore 11 has a diameter which is slightly greater than the outside diameter of a wire conductor 12 over which the tool is mounted. The forward end portion 13 of the tool is provided with a protuberance and as can be seen from FIGURES 2, 9, 10, 11 and 12, this protuberance may take various forms. Referring to FIGURES 2, 9 and 10, it is seen that theprotuberance is in the form of a hemispherical bead 15. This bead may be positioned at any desired peripheral location on the tool, different-examples being shown in FIGURES 9 and 10, the difference residing in the peripheral relationship of the head to a stop element later described. Alternatively, as seen in FIGURE 11, the forward end portion of the tool may be provided with a protuberance in the form of a semi-annular flange 20, or as seen in FIGURE 13, the forward portion of the tool may be formed to have a hexagonal configuration or other polysided configuration so as to have a plurality'of protuberances 20a. Regardless of the form for the protuberance, the radial dimension of the protuberance is such that the diametric distance between the outermost surface of the protuberance and the diametrically opposite side of the forward portion of the tool is sufficiently greater than the diameter of a bore 16 within an insulation block 17 of an electrical connector 18 in which a contact member 19 is positioned, so that an interference fit of the tool in the bore will frictionally retain the tool therein.

A stop element such as a rib 22 is provided on the tool spaced away from the forward end so that the tool will not inadvertently be inserted far enough in the bore to cause undesired release of a contact member positioned therein. This stop element may be in the form of the rib 22 (FIG. 9), a flange 23 (FIG. 11), or a button 24- (FIG. 12). Other equivalent forms of stop elements should readily suggest themselves to those skilled in this art. Whatever the form, it should present an abutting shoulder to meet the rearward face of the insulator when the tool is inserted into the bore far enough to attain the interference fit but not far enough to perform the contact releasing function.

The tool is preferably formed of plastic or rubber, and the thickness of the walls bears a relation to the character of the material, having in mind that it should have the requisite axial compressive rigidity, but must have a lateral resilient deformability so that it will yield diametrically but otter a resistance thereto, and will return to its original cross-sectional contour when free from restraint.

The resiliency may also be such as to enable the rearward portion 14 of the tool to be squeezed with finger pressure and thus provide for gripping the wire conduc tor 12. ,After the tool 10 has been inserted into the electrical connector and has released a contact retention clip 25, the contact member 19 may be extracted from the insulator by pulling on the wire or by squeezing the rearward portion 14 of the tool into gripping relationship with the wire conductor 12 and pulling rearwardly.

Referring to FIGURE 2, it is seen that the tool there illustrated is provided with a slit 26 which extends the entire axial length of the tool. This slit permits the tool to be spread open by finger-tip pressure and posi-.

tioned around an electrical conductor. Alternatively, as shown in FIGURE 9, the tool may be formed so as to constitute a continuous unitary cylindrical member. If the tool is formed in the latter fashion, it i placed upon an electrical conductor prior to attaching the conductor to its respective contact member.

In use, the tool may be retained on the conductor adjacent to but separated from the insulator as shown in FIG- URE 4. Preferably, however, it will be lodged inoperatively in the bore of the insulator as seen in FIGURE 5.

The electrical connector 18 as illustrated includes the insulation block 17 having a forward face 21 and a rearward face 27, with the contact member receiving bore 16 extending between the forward and rearward faces. The bore 16 includes a relatively large rearward portion 28 and a relatively small or constricted forward portion 29. The relatively largerearward bore portion 28- is undercut to provide an annular cavity 30 within which the contact retention clip is mounted. This clip includes a generally cylindrical body 31 which is preferably longitudinally slit so that the clip can be constricted and inserted into the annular cavity through the rear end of the bore and then permitted to expand outwardly against the wall of the bore in a seated position. It may be held in place by other means. The retention clip 25 includes one or more spring fingers or tines 32 which may be struck inwardly from the wall of the cylindrical body 31of the clip so as to angle forwardly and radially inwardly.

The wall of bore 16 presents a rearwardly facing shoulder 33 at the junction of the relatively large rearward bore portion 28 and the constricted forward bore portion 29.

'. The contact retention clip 25 and the bore configuration are adapted for snap-in contact mounting with the contact member being insertable into the bore from the rear and being removable from the rear. A suitable contact member 19 shown in FIGURES 3-7 includes a generally cylindrical body 34 having a forward contacting portion 35 which is illustrated in the drawing as a pin element but which may be a socket or any other type of contact means. An annular collar 36 is provided on the body 34 dividing the body 34 into a forward body portion 37 which is located within the constricted forward bore portion 29 and a rearward body portion 38 'which is of tubular construction to permit soldering or crimping therein of the end of the wire conductor 12.

In FIGURES 3, 4 and 5 the contact member 19 is shown in its releasably locked position within the insulation block, the contact members having been pushed forwardly into the bore 16 from the rear, the annular collars 36 on the contact members camming the spring fingers 32 of the contact retention clips 25 radially outwardly as the collars 36 pass under the spring fingers 32 and the spring fingers 32 then snapping radially inwardly behind the collars 36 to lock the contact members against rearward movement in the bores 16. Further forward move ment of any contact member in the bore is blocked by engagement of the collar 36 against the rearwardly facing shoulder 33 in the bore 16. It is to be noted that when the contact member 19 is positioned in its locked position, as shown in FIGURES 3, 4 and 5, an annular clearance 39 exists between the rearward body portion 38 of the contact member and the insulation on the wire conductor 12 on the one hand and the generally cylindrical body 31 of the clip 25 and the entrance to the rearward bore portion 28 on the other hand. This annular clearance 39 provides an annular access passage for insertion of the tool 10 from the rear.

Assuming that the tool is disposed in its inoperative position as shown in FIGURE 5, when it is desired to remove the contact member, the rear portion 14 of the tool is gripped, as shown in FIGURE 1, and pushed in a forward direction through the access passage 3? until the forward end 40 of the tool abuts against the annular collar 3e: on the contact member 19. The stop element 22 will be deflected inwardly when sufficient axial pressure is exerted for the purpose intended. This stop element preferably is formed with a tapered forward end shoulder 41. As the forward portion 13 of the tool passes under the spring fingers 32, it cams the fingers 32 radially outwardly so that the forward ends of the fingers will clear the annular collar 36 on the contact member 19. The external diameter of the forward portion 13 of the tool preferably is slightly greater than the diameter of collar 36 on the contact member so as to in sure that the spring fingers 32 will be cammed radially outwardly sufficiently to clear the collar36. The contact member 19 then is free to be withdrawn rearwardly from the insulation block.

To use the tool 10 for inserting a contact member, force is applied to move the tool in a forward direction until the forward end 40 of the tool engages the annular collar 36 of the contact member. The tool 10 is then pushed further forward so as to move the contact member forward within the bore 16 until the collar 36 abuts the rearward facing shoulder 33 in the here. The tool 10 is then pulled rearwardly permitting the spring fingers 32 to shift radially inwardly behind the collar 36 to the position shown in FIGURES 3, 4 and 5.

The rear section 14 of the tool may have an external diameter greater than any diameter of the forward and intermediate sections, presenting a safety stop shoulder 42, but can be made without this feature as illustrated in FIGURE 14.

While the instant invention has been shown and described herein in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein, but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

I claim:

1. A spaghetti type tool designed for retention on an insulated wire conductor attached to a contact terminal member and being adaptable to function as a generally cylindrical probe to push a flanged contact terminal member into place in the bore of an electrical connector insulator block or to displace a resilient locking element in the latter to free the contact terminal member for removal from said bore, said tool comprising an elongated tubular member having a bore extending entirely therethrough from a forward end to a rearward end, said bore having a diameter of such size as to loosely embrace said insulated wire and a contact terminal section extending therefrom, the outside surface of the forward end portion of said tubular member having a protruding major diameter near said forward end and a minor diameter, said tubular member being substantially rigid axially but resilient diametrically and deformable by manual effort to push the tool forwardly into the bore of the insulator block whereby the surfaces of the major diameter portions make an interference .fit with the wall of the bore,

frictional force of the interference fit being of a magnitude whereby the tool will be retained at the position in the bore where it is left but the tool may be manually moved axially either way in the bore.

2. A tool as defined in claim 1 wherein the forward end portion of the tubular member has a generally symmetrical circular outer surface which provides the minor diameter, and a protuberance which contributes to the major diameter.

3. A tool in accordance with claim 1 wherein said tubular member is formed from material having good electrical insulation properties said material also providing a flexible diametrical reinforcement for the conductor Wire.

4. A tool as defined in claim 1 in which a stop element is disposed on the outside surface of the tubular member intermediate the ends thereof but which is more remote from said forward end of the tubular member than said major diameter and presenting a shoulder facing the forward end adapted to stop against the surface of the insulator block but adapted to be displaced toward the axis of the tubular member to slide into the bore upon the application of a predetermined axial thrust.

5. A tool in accordance with claim 4 wherein said tubular member is formed from material having good electrical insulation properties said material also providing a flexible dia-metrical reinforcement for the conductor wire.

6. A tool for inserting and extracting a removable electrical contact in a bore of an electrical connector insulator block, said tool comprising an elongated tubular member, protruding means on a forward portion of said tubular member for removably securing said tool within said bore, and protruding means positioned on an intermediate portion of said tubular member for preventing unintended insertion of said tool beyond a predetermined point in said bore so as to thereby preclude the inadvertent removal of an electrical contact positioned within said bore.

7. A tool for inserting and extracting a removable electrical contact within a bore of an electrical connector insulator block, said tool comprising an elongated tubular member, said member having a forward, an intermediate and a rearward portion, protruding means positioned on the forward portion of said tubular member for removably securing said tool within said bore, protruding means positioned on the intermediate portion of said tubular member for preventing accidental insertion of said tool beyond a predetermined point in said bore, so as to thereby preclude the inadvertent removal of an electrical contact positioned within said bore, the internal bore of said tubular member loosely conforming to the external configuration of a wire conductor over which the tubular member is disposed when utilized to insert or extract the contact member, the rearward portion of said tubular member having sufficient dia-metric resiliency so as to be manually depressible into contacting relationship with the external surface of the wire conductor and thereby facilitate the manipulation of the electrical conductor and the contact member connected thereto.

8. A tool for inserting and extracting a removable electrical contact Within a bore of an electrical connector insulator block, said tool comprising an elongated tubular member, said elongated tubular member having a forward, an intermediate and a rearward portion, the forward portion of said tubular member having a polysided configuration so as .to provide the forward portion with a multiplicity of protuberances for removably securing said tool within said bore, and means positioned on the intermediate portion of said tubular member for pre venting unintended insertion of said tool beyond a predetermined point in said bore so as to thereby preclude the inadvertent removal of an electrical contact positioned within said bore.

9. A spaghetti type tool designed for retention on an insulated wire conductor attached to a contact terminal member and being adaptable to function as a generally cylindrical probe to push a flanged contact terminal member into place in the bore of an electrical connector insulator block or to displace a resilient locking element in the latter to free the contact terminal member for removal from said bore, said tool comprising an elongated tubular member having a bore extending entirely therethrough from a forward end to a rearward end, said bore having a diameter of such size as to loosely embrace said insulated wire and a contact terminal section extending therefrom, the outside surface of the forward end portion of saidtubular member having a major diameter and a minor diameter, said tubular member being substantially rigid axially but resilient diametrically and deformable by manual effort to push the tool forwardly into the bore of the insulator block whereby the surfaces of the major diameter portions make an interference fit with the wall of the bore, frictional force of the interference fit being of a magnitude whereby the tool will be retained at the position in the bore where it is left but the tool may be manually moved axially either way in the bore, and a stop element comprising an elongated rib which is disposed on the outside surface of the tubular member intermediate the ends thereof that presents a shoulder which is a forward tapered end of the, rib that faces the forward end of the tubular member adapted to stop against the surface of the insulator block but is adapted to. be displaced toward the axis of the tubular member to slide into the bore upon application of a predetermined axial thrust.

10. A spaghetti type tool designed for retention on an insulated wire conductor attached to a contact terminal member and being adaptable to function as a generally cylindrical probe to push a flanged contact terminal member into place, in the bore of an electrical connector insulator block or to displace a resilient locking element in the latter to free the contact terminal member for removal from said bore, said tool comprising an elongated tubular member having a bore extending entirely therethrough from a forward end to a rearward end, said bore having a diameter of such size as to loosely embrace said insulated wire and a contact terminal section extending therefrom, the outside surface of the forward end portion of said tubular member having a major diameter and a minor diameter, said tubular member being substantially rigid axially but resilient diametrically and deformable by manual effort to push the tool forwardly into the bore of the insulator block whereby the surfaces of the major diameter portions make an interference fit with the wall of the bore, frictional force of the interference fit being of a magnitude whereby the tool will be retained at the position in the bore where it is left but the tool may be manually moved axially either way in the bore, a stop element comprising an elongated rib which is disposed on the outside surface of the tubular member intermediate the ends thereof wherein the length of the tubular member from the forward end to the rearward end of the elongated rib is approximately equal to the total distance which the tool requires to be inserted and the elongated rib presents a shoulder which is a forward tapered end of the rib that faces the forward end of the tubular member adapted to stop against the surface of the insulator block but is adapted to be displaced toward the axis of the tubular member to slide into the bore upon application of a predetermined axial thrust said tubular member having an enlarged outside diameter commencing at the rearward end of the rib presenting a safety stop shoulder.

11. A spaghetti type tool designed for retention on an insulated wire conductor attached to a contact terminal member and being adaptable to function as a generally cylindrical probe to push a flanged contact terminal member into place in the bore of an electrical connector insulator blockor to displace a resilient locking element in the latter to free the contact terminal member for removal from said bore, said tool comprising an elongated tubular member having a bore extending entirely therethrough from a forward end to a rearward end, said bore having a diameter of such size as to loosely embrace said insulated wire and a contact terminal section extending therefrom, the outside surface of the forward end portion of said tubular member having a major diameter and a generally symmetrical circular minor diameter, wherein a protuberance contributes to the major diameter said tubular member being substantially rigid axially but resilient diametrically and deformable by manual effort to push the tool forwardly into the bore of the insulator block whereby the surfaces of the major diameter portions make an interference fit with the wall of the bore,

frictional force of the interference fit being of a magni tude whereby the tool will be retained at the position in the bore where it is left but the tool may be manually moved axially either way in the bore, a stop element comprising an elongated rib which is disposed on the outside surface of the tubular member intermediate the ends thereof wherein the length of the tubular member from the forward end to the rearward end of the elongated rib is approximately equal to the total distance which the tool requires to be inserted and the elongated rib presents a shoulder which is a forward tapered end of the rib that faces the forward end of the tubular member adapted to stop against the surface of the insulator block but is adapted to be displaced toward the axis of the tubular member to slide into the bore upon application of a predetermined axial thrust said tubular member having an enlarged outside diameter commencing at the rearward end of the rib presenting a safety stop shoulder.

12. A tool for inserting and extracting a removable electrical contact in a bore of an electrical connector insulator block, said tool comprising an elongated tubular member, means in the general form of a bead on said tubular member for removably securing said tool within said bore, and means positioned on an intermediate portion of said tubular member for preventing unintended insertion of said tool beyond a predetermined point in said bore so as to thereby preclude the inadvertent removal of an electrical contact positioned within said bore.

13. A tool for inserting and extracting a removable electrical contact in a bore of an electrical connector insulator block, said tool comprising an elongated tubular member, means in the form of a semiannular flange on said tubular member for removably securing said tool within said bore, and means positioned on an intermediate portion of said tubular member for preventing unin tended insertion of said tool beyond a predetermined point in said bore so as to thereby preclude the inadvertent removal of an electrical contact positioned with in said bore.

14. A tool for inserting and extracting a removable electrical contact in a bore of an electrical connector insulator block, said tool comprising an elongated tubular member, means on said tubular member for removably securing said tool Within said bore, and means in the form of a raised rib positioned on an intermediate portion of said tubular member for preventing unintended insertion of said tool beyond a predetermined point in said bore so as to thereby preclude the inadvertent removal of an electrical contact positioned within said bore.

References Cited by the Examiner UNITED STATES PATENTS 2,995,812 8/61 Bates 29-203 3,110,093 11/63 Johnson 29203 3,121,282 2/64 Donee 29206 WHITMORE A. WILTZ, Primary Examiner.

THOMAS H. EAGER, Examiner.

Claims

1. A SPAGHETTI TYPE TOOL DESIGNED FOR RETENTION ON AN INSULATED WIRE CONDUCTOR ATTACHED TO A CONTACT TERMINAL MEMBER AND BEING ADAPTABLE TO FUNCTION AS A GENERALLY CYLINDRICAL PROBE TO PUSH A FLANGED CONTACT TERMINAL MEMBER INTO PLACE IN THE BORE OF AN ELECTRICAL CONNECTOR INSULATOR BLOCK OR TO DISPLACE A RESILIENT LOCKING ELEMENT IN THE LATTER OF FREE THE CONTACT TERMINAL MEMBER FOR REMOVAL FROM SAID BORE, SAID TOOL COMPRISING AN ELONGATED TUBULAR MEMBER HAVING A BORE EXTENDING ENTIRELY THERETHROUGH FROM A FORWARD END TO A REARWARD END, SAID BORE HAVING A DIAMETER OF SUCH SIZE AS TO LOOSELY EMBRACE SAID INSULATED WIRE AND A CONTACT TERMINAL SECTION EXTENDING THEREFROM, THE OUTSIDE SURFACE OF THE FORWARD END PORTION OF SAID TUBULAR MEMBER HAVING A PROTRUDING MAJOR DIAMETER NEAR SAID FORWARD END AND A MINOR DIAMETER, SAID TUBULAR MEMBER BEING SUBSTANTIALLY RIGID AXIALLY BUT RESILIENT DIAMETRICALLY AND DEFORMABLE BY MANUAL EFFORT TO PUSH THE TOOL FORWARDLY INTO THE BORE OF THE INSULATOR BLOCK WHEREBY THE SURFACE OF THE MAJOR DIAMETER PORTIONS MAKE AN INTERFERENCE FIT WITH THE WALL OF THE BORE, FRICTIONAL FORCE OF THE INTERFERENCE FIT BEING OF A MAGNITUDE WHEREBY THE TOOL WILL BE RETAINED AT THE POSITION IN THE BORE WHERE IT IS LEFT BUT HTE TOOL MAY BE MANUALLY MOVED AXIALLY EITHER WAY IN THE BORE.