US 3210832 A
Description (OCR text may contain errors)
Oct. 12, 1965 G. H. KALEN INSERTION-REMOVAL TOOL Iii/rill I; HI VIII/1147 6 Filed April 24, 1964 INVENTOR. A4bfijiy6 H. KALEN lllllllllnlvllllllf fi ATTORNEYS United States Patent 3,210,832 INSERTION-REMOVAL TOOL George H. Kalen, 1060 Camphill Road, Fort Washington, Pa. Filed Apr. 24, 1964, Ser. No. 362,530 12 Claims. '(Cl. 29-203) (Granted under Title 35, US. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
This invention relates to hand tools and more particularly to hand tools for inserting and extracting removable contacts or pins from electrical connectors.
Electrical connectors utilizing removeable, crimp-type pin or socket contacts have been widely accepted in the electrical arts and are used in vast numbers, particularly in the construction of complex circuits in computers or the like where large numbers of connections are required and relatively small diameter wires are involved. Electrical connections are made with pin-type or socket-type contacts by merely inserting the contact into the connector or receptacle until the contact has the proper mechanical interlock within the connector. This mechanical interlock may be obtained by the use of a spring clip mechanism previously installed within the connector body. The connector may provide multiple openings for several contacts so that several conductors can be connected at a common junction. If the contacts are inserted properly into the connector, it will withstand substantial pull-out forces and the electrical integrity of the connection between the pin and the connector will be resistant to the deleterious effects of, for example, vibration and corrosion.
It is readily seen that the efficiency of the electrical connection is dependent upon the proper placement ofthe contact within the connector and the maintenance of the structural integrity of the receptacle during the insertion and removal operation. In order to effect the proper connection between the contact and the connector and to facilitate the subsequent removal thereof, hand tools of various configurations have been utilized. When these prior art hand tools are used for insertion, the contact member is held by the tip of the tool and inserted into the connector by a pushing action. In order to seat the contact into the proper cavity formed within the connector, a twisting or cocking action is applied by the operator of the tool. This action frequently has the effect of destroying the structural integrity of the material forming the connector insert body. Frequently during insertion of the contacts the tool encounters a resistance to insertion which may be due to either misalignment of the insertion tool or overhang of the material forming the body of the connector. This encountered resistance is frequently countered by the operator applying an increased force without providing sufficient time for the inserted contact to properly align and seat itself. In many instances this causes tearing of the material forming the walls of the contact apertures in the insert body of the connector, exiting of the contact through an adjacent opening, or damage to the contact retention member that was placed within the insert body of the connector. The aforementioned damages may also occur during the removal of the contacts from the electrical connectors.
It has been found that the soundness of an electrical connection between an inserted pin or socket and a connector can be established if a pull-out test force is applied to the contact. For example, one contact will, after proper insertion, withstand a pull-out force of up to 25 pounds but an improperly inserted one will be removed from the connector if a pull-out test force of a fraction ice of that amount is applied. Thus, the soundness of the connection can be established at the time of insertion if a pull-out test force slightly less than 25 pounds is applied.
The general purpose of this invention is to provide an insertion and removal tool for electrical connectors which embraces all the advantages of similarly employed prior art devices and possesses none of the aforesaid described disadvantages. To attain this, the present invention contemplates a unique tool consisting of a pneumatic cylinder handle assembly and insertion probe and removable probe assemblies interchangeable therewith. By reason of the pneumatic action of the tool, twisting or pushing of a secondary part is not necessary to effect the insertion or removal of a contact from an electrical connector and insertion and removal is accomplished without damage to the contact retention mechanism, the material of the connector or to the contact.
An object of the present invention is to provide an implement or tool for connecting or disconnecting mating electrical components in a manner to insure optimum mechanical and electrical engagement between said units without injury to or impairment of either.
Another object of the present invention is the provision of a general purpose, universal type insertion and removal tool assembly for inserting electrical contacts into electrical connectors and for extracting electrical contacts from electrical connectors.
Still another object is to provide a general purpose, universal type insertion tool embodying a compulsory pull-out test feature so that each contact inserted with the tool must be pull tested by the operator.
A further object is to provide a tool by which a contact attached to a Wire end, may while held by the tool, be telescoped and engaged within a connecting member quickly and securely in a simple operation even where the available working space is limited and the parts are not otherwise readily accessible.
A further object of the invention is to provide a contact-applying tool which may also be employed for disconnecting the contact from its contact retention member to which it is mechanically engaged.
Other objects and features of the invention will become apparent to those skilled in the art as the disclosure is made in the following description of an embodiment of the invention as illustrated in the accompanying sheet of drawing in which:
FIG. 1 is a full view of an embodiment of the present invention with a socket contact removal probe secured thereto;
FIG. 2 is a cross sectional view taken along the line 22 of FIG. 1;
FIG. 3 is a partial view in cross section of the pin contact removal probe;
FIG. 4 is a partial view in cross section of the insertion probe of the present invention with a socket contact engaged thereby;
FIG. 5 is a cross sectional view taken along the line 5-5 of FIG. 4; and
FIG. 6 is a cross sectional view of a connector with a socket contact secured thereto about to be extracted there from by the action of the removal probe of FIGS. 1 and 2.
In the illustrated embodiment of the invention, FIG. 1 shows a hand tool generally noted at 10 consisting of a handle assembly 11 and a probe assembly 12. Although the probe assembly 12 of FIGS. 1 and 2 is of the socketremoval-type, it is understood that the handle assembly 11 is not limited in the use thereof with removal probe 12 and that the probe 12 may be substituted, as will be described below, by pin-type removal probe assembly 12a of FIG. 3 and insertion probe assembly 13 of FIG. 4.
The hand tool of the present invention is particularly adapted for use in the environment illustrated in FIG. 6 which illustrates an enlarged longitudinal cross section view of a standard electrical connector insert 100 and which forms no part of the present invention. The connector insert 100 includes body portions 101 and 102 of resilient material separated by a fibrous element 104. A plurality of apertures, only one of which is shown at 105, extend longitudinally of the connector insert 100 and each houses a spring clip retaining element or contact retention member 110 of conventional type known and used in the art which is introduced into connector insert 100 prior to the insertion of the pin-type or sockettype contact. A socket-type contact is shown at 111 and is also of conventional design and of the type known and used in the art.
As noted in FIG. 6, contact 111 includes a pair of retention shoulders 115 and 1116 which, when properly seated with respect to the spring clip 110, are in locking engagement with surfaces 1 15a and 1116a, respectively, of clip 110. Surface 1116:: is formed as a portion of a flexible skirt 120 which in turn terminates in a lip 121 having angularly related surfaces 122 constructed for wedging engagement with the angular edge 64 of the tapered neck portion 60 to be described below.
Referring now to FIGS. 1 and 2 for a detailed description of the hand tool 10, the handle assembly or pneumatic cylinder 11 is illustrated as comprising a cylindrical tube 20 of stainless steel or the like which is internally threaded at 21 for receiving an externally threaded body plug 23 for sealing one end of the tube 20. An O-ring seal '24 is additionally provided between the plug 23 and tube 20 to insure an air-tight seal at the end of the tube. It should be understood that without departing from the scope of the present invention, the tube 20 may be constructed of reamed bar stock with the end portion thereof remaining to form the sealed end.
A piston assembly generally noted at 30 is longitudinally slidable within the cylinder 20 and includes a piston rod 31 having a threaded portion 32 for threadably receiving a piston 35. A nut 33 on threaded portion 3 2 wedgingly locks piston 35 with respect to rod 31. Piston 35 is constructed of .a deformable, flexible, resilient material, such as Teflon or the like, and includes both a solid body portion 36 having an internally threaded section 37 for receiving the threaded piston rod 31 and a relatively thin, longitudinally tapering circumferential lip component 38 forming a cup 39 facing the sealed end of the tube 20 By reason of the resiliency and flexibility of the lip 38 an increasingly effective seal is obtained as the piston rod 31 and associated piston 35 is urged toward the sealed end of the tube 20. As the air contained between the piston and sealed end is compressed, compressive forces are produced which urge the circumferential lip 38 against the inner sidewalls of the tube 20. By reason of the adjustable character of the piston 35 with respect to piston rod 31, the compressive force developed per increment of piston rod travel may be varied.
The cup 39 of the piston 35 additionally serves as a housing for receiving a compression spring 40 which is interposed between the piston and the body plug 23. The compression spring 40 continually acts to urge the piston rod 31 outwardly of the cylindrical tube 20 and serves an important part in the insertion and removal functions described below.
The other end of tube 20 has an externally threaded portion 42 which receives an internally threaded nut 43 which serves to lock the probe assembly 12 within the cylindrical handle assembly 11. The probe assembly 12 illustrated in FIGS. 1 and 2 is of the type used in the removal of a socket-type contact similar to that illustrated at \111 in FIG. 6 and includes a probe tip generally noted at 50 and longitudinally slidable within a probe body 51 which houses and guides the tip 50.
Probe tip is composed of a shaft 52 which terminates at one end in a reduced portion 53 of a diameter slightly smaller than the diameter of the socket of the contact member to be removed. By reason of the reduced portion 53, a shoulder 54 is formed which in the removal operation, FIG. 6, abuts the end of the socket contact. A collar 55 is integrally connected to the shaft 53, is of larger diameter and slides within the inner confines of probe body 1 2.
The probe body 51 includes a tapered, reduced neck portion having a bore 61 therethrough for receiving the shaft of the probe tip 50 and an enlarged portion 62 having a counter bore 63 therein for permitting longitudinal sliding movement of the collar 55. The counter bore 63 in turn terminates in a shoulder 66 which limits the forward movement of shaft 52. The reduced neck portion 60 is of tapered configuration for ease of insertion and further includes an angular edge 64 for engaging and separating the flexible skirt 120 of the clip 110, See FIG. 6.
Probe body 51 has a portion thereof telescopically received within the cylindrical tube 20 and includes an annular flange 65. An annular flange 65 which is formed about the probe body 51 for abutment against the end of tube 20 and is rigidly held in this position by the engagement of complementary surfaces formed on the annular flange 65 and the nut 43 when the latter is threaded upon the threaded end 44 of the tube 20.
Probe body 51 terminates at the other end thereof in an internally threaded portion 68 which receives a threaded bushing 70 which in turn includes an aperture 71 formed therein of a diameter greater than the diameter of the piston rod 31.
In the assembly of the probe assembly 12 within the pneumatic cylinder 11, the probe lock nut 43 is removed from the tube 20 and the probe 12 inserted within the tube .20 with the piston rod 31 passing through the aperture 71 in the bushing 70. The probe lock nut is then passed over the probe assembly 12 and threaded on the threaded portion 44 of the tube 20 which draws the angular flange 65 into engagement with the end of the tube 20. In this secured position, the piston rod 31 urges the probe tip to the outermost extended position.
In like manner removal probe 12a and insertion probe 13 may be substituted and inserted for the removal probe 12 shown in FIGS. 1 and 2. Probe 12a of FIG. 3 differs from probe 12 of FIGS. 1 and 2 in the construction of the probe tip 50a; the probe body 51a being identical in construction to probe body 50 of FIGS. 1 and 2 with the counter bore 63 terminating in a shoulder 66a which limits the forward movement of shaft 52a. Removal probe 12a is of the type used in the extraction of a pintype removable contact and includes a probe tip 50a having a shaft 52a secured at one end thereof to collar 55a and the other end formed with a bore 75 of a diameter suflicient to envelope the outwardly extending pin of the contact to be removed and not shown.
Insertion probe 13 of FIG. 4 is also adapted for use with the pneumatic cylinder 11 and includes a probe tip and a probe body or housing 81, body 81 being similar to body 51 of FIG. 2 except that the neck 60 has been eliminated. A barrel or shaft 82 forms part of the insertion probe tip 80 and has secured at one end thereof a collar which is longitudinally slidable within the counter bore 83 formed in the probe body 81. The counter bore 83 in turn terminates in a shoulder 84 which limits the forward movement of shaft 82. Barrel 82 is recessed at 86 to house wire 111a and includes a tapered hollow end 87 provided with an opening 88 for receiving the contact 111 which is to be inserted in the electrical connector insert 100. As illustrated in FIG. 5, the tapered end 87 is formed with a plurality of slots 90 at the outermost portion to provide a plurality of expandable and resilient spring fingers 91 to securely hmontact 111. The material used in the construction of the tapered portion and the width and length of the slots 90 will determine the amount of holding power that the insertion probe will exhibit against a pullout force applied to the contact.
For purposes of illustration and not limitation, the following description of the use of the insertion tool will be described as the same is used in the insertion of a socket type contact 111. It is understood that a pin type or other types of connectors may be utilized with the insertion tool without departing from the spirit and scope of the present invention. In operation, the insertion probe assembly is secured to the handle assembly as described above and the socket-type contact 111 is inserted in the tapered hollow end 87 of the insertion probe tip 80 and is held by the resilient action of the spring fingers 91. The contact and probe tip is inserted into the aperture 105 of the electrical connector insert 100, entering the left side thereof as viewed in FIG. 6. Continual force is applied by the operator until the contact is properly seated in the spring clip 110 which occurs when the spring elements engage the retaining shoulders formed in the contact member 111. Upon proper seating of the contact 111 in the clip 110, the probe tip 80 may be removed since the retaining force of the clip will overcome the resilient retaining force of the spring fingers 91. It is understood that should any misalignment occur during the insertion of the contact which would inhibit the forward movement of a probe tip and contact, a further application of force by the operator will cause the probe body to telescope over the static probe tip and thereby provide sutficient time for the contact to free itself from its impediment and to be subsequently properly seated by the combined forces of the spring 40 and the compressed air.
Referring now to FIG. 6 for a description of the method of extracting a contact from the seated position thereof in the electrical connector, the proper removal probe is selected depending upon the diameter of the socket portion of the contact member and the selected probe assembly is secured to the pneumatic cylinder. The reduced shaft 53 of the probe tip is inserted in the socket portion of the contact and an axial force is applied by the operator. Upon application of this force, forward movement of the probe tip 50 is inhibited by the engagement of the shoulder 54 and the socket end. Continued application of force causes the probe body 51 to telescope over the probe tip and the tapered neck 60 to proceed into the body of the connector. As this forward motion occurs, the pressure in the pneumatic cylinder is building up. When the angular edge 64 engages the surface 122' of the spring 110 and the flexible skirt 120 spreads to release the contact the pressure will urge the piston, the associated piston rod and the probe tip to quickly move forward and eject the contact.
In the manner similar to that described above the removal probe illustrated in FIG. 3 may be utilized in the extraction of a pin-type removable contact.
Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
What is claimed is:
1. A hand implement for inserting and extracting removable contacts from electrical connectors, comprising:
a tubular member pneumatically sealed at one end thereof and open at the other end thereof;
piston means interposed within and slidably engaging said tubular member, said piston means having a force-transmitting means secured thereto;
spring means interposed between said piston means and said sealed end of said tubular member;
housing means having a longitudinally extending bore therethrough;
a shaft slidably positioned within said bore, said shaft terminating at one end thereof in a removablecontact engaging portion which extends beyond the confines of said housing means;
means at each end of said bore for abutting said shaft and limiting the movement of said shaft within said housing means;
said force exerting means extending within said housing means and engaging said shaft; and
locking means operatively securing said housing means to said tubular member.
2. A hand implement for inserting and extracting removable contacts from electrical connectors which employ spring clips for grasping a portion of the body of the contact, comprising:
a hollow tube pneumatically sealed at one end thereof and open at the other end thereof;
pneumatic piston means interposed within and fitted to said hollow tube for movement therein, said piston means having a longitudinally extending piston rod secured at one end thereof to outer face of said piston means;
mechanical spring means interposed between the inwardly facing surface of said pneumatic piston means and said pneumatically sealed end of said tube;
housing means having a longitudinally extending bore therethrough;
a shaft slidably positioned within said bore, said shaft terminating at one end thereof in a contact engaging portion which extends beyond the confines of said housing means and terminating at the other end iri an enlarged collar portion;
first abutment means at the forward end of said bore for engaging said collar portion and limiting the forward movement of said collar portion;
second abutment means at the other end of said bore for limiting the rearward movement of said collar portion;
said piston rod extending within said housing, engaging said collar and urging said collar against said first abutment means; and
locking means operatively securing said housing means to said hollow tube.
3. The hand implement as defined in claim 2 wherein said pneumatic piston means includes a rearwardly facing dished portion for housing a portion of said spring means and for entrapping the air between said piston and said pneumatically sealed end of said tube.
4. The hand implement as defined in claim 3 wherein said dished portion is formed by a rearwardly extending, flexible, circumferential lip which engages the inside periphery of said tube whereby a seal is formed precluding the escape of the entrapped air.
5. The hand implement as defined in claim 4 wherein said piston rod is adjustable with respect to said pneumatic piston whereby the compressive force, resulting from the compression of the entrapped air and the compression of said spring means, acting on said piston per increment of relative movement between said piston rod and said tube may be regulated.
6. The hand implement as defined in claim 2 wherein:
said second abutment means is a closure threadably se cured to said other end of said bore having an aperture therethrough through which the piston rod extends.
7. The hand implement as defined in claim 2 wherein:
said shaft includes a recess extending longitudinally along a portion of the length of said shaft; and wherein said contact engaging portion of said shaft comprises a plurality of expandible resilient fingers for gripping the contact.
8. The hand implement as defined in claim 2 wherein:
said shaft includes a recess extending longitudinally along a substantial portion of the length of said shaft; and wherein said contact engaging portion of said shaft is tapered to facilitate entry thereof into the connector and comprises a plurality of expandible resilient fingers for gripping the contact.
9. A hand implement as defined in claim 2 wherein:
said contact engaging portion at said one end of said shaft includes a reduced diameter pin member for insertion Within a portion of the contact.
10. A hand implement as defined in claim 9 wherein:
said housing surrounding said shaft and collar includes a tapered longitudinally extending reduced neck portion for engaging the spring clip and for releasing the grasp thereof on the contact.
11. A hand implement as defined in claim 2 wherein:
said contact engaging portion at said one end of said shaft includes a bore for receiving a portion of the contact.
12. A hand implement as defined in claim 11 wherein:
said housing surrounding said shaft and collar includes a tapered longitudinally extending reduced neck portion for engaging the spring clip and for releasing the grasp thereon on the contact.
References Cited by the Examiner UNITED STATES PATENTS WHITMORE A. WILTZ, Primary Examiner.
THOMAS H. EAGER, Examiner.