US2510944A - Electrical connector - Google Patents

Description

l. L. AUERBACH ELECTRICAL CONNECTOR June 13, 1950 Filed Sept. 27, 1946 ISAAC L. AUERBACH maidim 13, 195o stromen. oomc'roa um L. Auerbach, unina sm Navy application september 21, 194s, serial No. mm

' 1 chime `(ci. 11a-32s) (Granted under the lot of March 3, 1883,

amended April 30, 1928; 37| 0. G. 757) This invention relates to electrical connectors and more particularly to an electrical connector embodying in one device the advantages oi a terminal strip and the advantages of a plug connector. Q

Nearly all electrical and electronic apparatus require connection to externally located apparatus ii it be only the source of electric power. It y is further desired in some types of equipment to have small sections of the whole removable to facilitate rapid replacement, trouble shooting. and repair. More speciilcally, radio equipment assembled in a console is usually composed oi a number oi separate chassis which can be removed from the console; and in many designs a small section of a single chassis can be exchanged by simply unplugging i'rom the rest of the chassis. In the foregoing examples provisions must be made for making the required electrical connections between the removable part and its associated equipment. This has usually been accomplished by multi-conductor cables and plugs joining either at the front of the removable unit by threaded couplings or at the base in such a manner that the plugs are connected by the replace'- ment of the unit. There are several disadvantages incident to such connection, the conductors are not available for test measurements unless the plugs are disconnected, and then the circuits are not energized. Even with the plugsdisconnected the contacts are difficult to reach and the circuits diillcult to trace. Furthermore, in many types of electrical connectors there is an undesirable resistance between corresponding contacts. It would be an advantage in many types of equipment to disconnect one circuit from another located on the same chassis without unsoldering or unscrewing a number of terminals.

It is an object of this invention to provide an electrical terminal strip which may be joined with a similar terminal strip to constitute an electrical connector.

It is another object of this invention to provide pairs o1 connectable terminal strips having very low contact resistance yet easily connected or disconnected.

It is another object of this invention to provide pairs of connectable electrical terminal .strips with solderless connections having the electrical and physical isolation characteristics of soldered connections.

It is another object of this invention to provide pairs of connectable electrical terminal strips which may be manufactured with some accommodate no more than a lesser number of,i y*

conductors as a means oi lsaving space and eliminating unused terminals. f

It is another object oi this invention to provide pairs of connectable terminalstrips easily accessible to test leads.

Other objects, advantages and novel aspects of the invention lie in certain details of' construc-l tion as well as the cooperative relation of the component parts and will .be apparent from the following description and accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views.

In the drawings:

Fig. 1 is alperspective view o! one embodiment of the invention.

Fig. 2 is a cross-sectional view of the embodiment in Fig. 1 taken through any pair of corresponding terminals.

Fig. 3 is a partially out away perspective view of another embodiment oi' the invention.

Fig. 4 is a cross-sectional view of the embodiment in Fig. 3 taken through any pair of co responding terminals.

Fig. 5 is a perspective view oi a device for mechanically engaging or disengaging the embodiments in thepreceding iigures.

Briey, this invention provides pairs of terminal strips which can be joined together and 'which may be simply constructed from flat 'insulating blocks, preferably molded to a desirable shape, each supporting an equal number of metal springs, each metal spring providing a contact surface for a terminal, and in addition, engaging a corresponding metal spring from the other block upon the joining together of said pair of blocks. Thus a means Vof plug-in connection between terminal strips is provided.

The invention may be better understood by reference to Fig. 1 in detail, which shows a pern spective View of one embodiment of the invention as seen from slightlyV above and to one side. Two insulating blocks 6 and 1' comprise the bulk of the device and should be made of some insulating material, preferably one of high dielectric that can be molded to the shapes here shown.

, Each block is essentially a long, generally rectangular, strip, the length being determined by the number of terminals desired. The shape of the two blocks departs from the rectangular in the manner shown in the drawing in order that each may be more suitable for its purpose. 'I'he male connector terminal block 6 has a nat spring standard number of terminals and easily cut to le i3 for each terminal. each spring may be at- 3 tached to the block by a sleeve 29 inserted vertically into a suitable hole in the block and having a flange at its upper end to retain said spring. This function will be disclosed more completely below in reference to Fig. -il. Upon the inner periphery of said sleeves 20 threads may be cut suitable to receive the terminal screws I2. Said retaining flange of said sleeves 20 is preferably square and sized to closely flt between the barriers 3 described below so that they cannot turn with the terminal screws I2. Said screws I2 provide a means of connecting wires to the ter minal block. The holes provided in the block for each sleeve 20 may be used with longer screws I8 to mount said block. By using the same holes for mounting, a long block may be cut to any desired length and the'end terminal screw I2 replaced by a mounting screw I3. The end metal spring I3 could also be removed before inserting the mounting, screw I8. It ls desirable to mold the block with raised ridges or barriers 8 located transverse the long axis of the block between the terminal screws I2. Said barriers 8 will prevent shorts between adjacent terminals that might otherwise be caused by one or more loose wires or occur during the connection or disconnection of a conductor to a terminal and will further provide a -higher dielectric between terminals to improve the voltage rating of the device. Each metal spring I3 attached to the male block 6 has sullicient length to protrude from one edge of the block. It is this side of the male block ,6 that is abutted to the female block 1 to electrically connect the two blocks. When so abutted each spring I3 will penetrate a suitable orifice in the female block 1 and engage a second metal spring I mounted on said female block 1. The springs may be made of any suitare similarly provided in the abutting surface of the female block 1 to receive the guiding studs I6. Said studs not only guide the male springs into the female block but also insure that said springs are inserted into the proper contacts. It should be understood that the embodiments have been illustrated with three terminals only to simplify disclosure. The blocks may be made in any length which may easily be cut into shorter lengths to accommodate the number of terminals desired and the space available.

The cross-sectional View shown in Fig. 2, to which reference is now made, is taken transverse to the long dimension of Fig. l, through any pair of corresponding terminal screws I2 and I4. The bloekaffand 1 are here shown almost completely joiheditogether in order to demonstrate the engaging `oftheir respective springs A I3 and I5. This view illustrates the height relation of the barriers 3 of block and the barriers .3 of block 1, and as well, the relative size of the ledge I0 in respect to the barriers 8 and the lip II in respect to the barriers 9. As shown. the lower or engaging edge of the ledge I0 is chamferred, as is the lower engaging edge of the lip II, thus permitting the blocks to be joined together without binding or catching. Each hole in the male block for the terminal screws I2 is fitted with a metal sleeve 20 threaded upon its inner periphery to receive said screws I2. Each said sleeve 20 has a retaining flange at its upper end to hold the spring I3 and is peened at its lower end to anchor it securely in the block I.

able conducting material preferably of beryllium copper, plated with silver. The male block 6 and the female block 1 are shown separated in Fig. 1, as here shown the male block 6 is shaped so as to have a ledge I0 projecting from its top. parallel to its base and overhanging the portion of each spring I3 which protrudes from the block. This ledge is designed to protect the projecting male springs from contact with foreign objects when the blocks are not joined together. It should be noted that the barriers offer simil-ar protection to the terminals whether or not the blocks are engaged. Said ledge I0 may also act as a guide for the male springs while the two blocks are being joined together. The female block 1 is in general similar to the male block 6. Each spring I5 is mounted by a flanged-sleeve 2 I threaded for the terminal screws I4, and the same holes can be used for the mounting screws Il as for the terminal screws I4. However, the metal springs I5 are curved at one end as will be more clearly indicated below in reference to Flg. 2. These terminals are also separated by barriers 9, the tops of said barriers 3 at the abutting side of said block 1 are joined by a retaining lip II so as to leave a suitable orifice between each pair of barriers for the insertion of the male spring I3. The barriers l of block 3 are higher than the barriers 9 of block 1, the height relationship being such that the lower surface of the ledge III on block i will pass over the upper surface of the lip II of block 1 when the two blocks are joined together. A guiding stud may be projected outwardly and normal to the abutting surface of the male block 8 beyond the ends of the spring contacts I3 about every half dozen terminals. Suitable holes The threaded sleeve is preferred to a threaded hole in the block, it being simpler to add a threaded sleeve than cut threads in the block and the threads so obtained are more durable. The portion of the female -contact spring II which resides under the lip II is curved so thatthe center of its curvature presses against the underside of the said retaining lip. This pressure insures a good contact with the corresponding male spring and keeps contact surface of the said female spring clean when the blocks are .not joined together. The curvature brings the end of the spring back down to the surface of the block so that upon insertion, the male spring I3 will pass between the female spring I5 and the lip I I and not catch against the leading edge of said female spring I5, or go beneath. The screws I4 of the female block 1 screw into metal sleeves -identical to the sleeves 20 used in connection with the male block 3.

Referring to Fig. 3, another embodiment of 4 the invention is shown differing from Fig. 1 only in the shape of the blocks and the use of two female springs instead of one. In this embodiment the male block 22 has no ledge projecting above the male springs I3 but the block itself projects below the male springs. Sufficient clearance is provided between the block and the projecting springs for the lower female spring 23. The barriers 24 of the male block 22 are similar to those of Fig. l except they are not joined together at the top. The female block 23 may have two abutting surfaces in this embodiment. the lower one may abut the portion of the male block projecting below the springs, the upper one abuts the barriers 24 of the male block so that the material of the block rather than all is the insulation medium between the springs. Said upper abutting surface is the end of a ledge 28 projecting from the barriers 25 of the female block and overhanging the projecting ends of the female springs 21 and 2l. It may be observed l in `1"lg.3 that said ledge II includes) molectionofthefemalebarrierssoastosnclosesaid femslespringsl'landuponthreesides. Grooves corresponding to the projections of said ban'iersareshownintheportlonofmaleblock 22 projecting belowtheinsertable end ofthemale springs i3, and upon Joining of the blocks said -othersaidplatform,manipulatingthailandia33' grooves will receive the lower edges of the prov Jections of said barriers 25. By means of said barrier projections fitting in said grooves.' a dlelectric better than air is provided between the different springs when the blocks are Joined. The lower female spring 23 rides upon the pro- Jection of block 22 when the block are engaged to increase the contact pressure of the springs. The female springs are preferably a pair of similarly curved metal springs. fiat at one en d through which a hole may be made for mounting same with the terminal screw i4. Said springs2land23aremountedbacktobackso that they press against each other at the center of their curvatures. The male spring I3 inserts between said female springs upon the joining of the two blocks 22 and 23.

The layout of the metal springs used in the second embodiment may be more easily understood from the cross-sectional view in Fig. 4, to which reference is now made. The male and female block are here partially joined to demonstrate the engaging of the springs. It will be noted that the female springs 21 and 23 fit snugly between the lower projection of the male block 22 and the upper projection 25 of the female block 23. This insures a firm contact with the inserted male spring I3. The upper projecting ledge 25 has a bead 23 along the lower edge of its abutting surface between the barrier projections. This bead 29 permits insertion of the male spring i3 without binding or catching. The relative dimensions of the barriers 24 and 25, the blocks 22 and 23, and the projecting ledge 25 are more clearly indicated in this figure. The pressure between the female springs 21 and 28 keeps them clean when the blocks are not joined. Also, the insertion of the metal spring makes a long wiping contact which further cleans the contact surfaces. These connectors have been found by measurement to oder a contact resistance of the order of .0008 ohm.

Fig. 5 shows a device which may be used to connect and disconnect a pair of terminal connectors such as exemplified in the rst four figures. 'I'he use of this device would liken the invention to a multi-pole single throw knife switch. The device operates with a movable platform 34, having pins 31 protruding laterally one each from two side members 39 and 43 of the said movable platform 34. Said pins are engaged in elongated slots 38 at the ends of the U-shaped handle 33. Said' U-shaped handle 33 may be pivoted .upon its parallel members. Said parallel members are pivotable mounted by means such as rivets 36 to a pair of stanchlons 3| and 32 suitably mounted vertically-upon opposite sides of a base plate 30. Moving said handle 33 counterclockwise about its pivots 36 will slide the movable platform 34 to the right along the base plate 30. A stationary platform is mounted on the right side of the base plate 30. Moving the handle 33 as described slides the movable platform 34 toward the stationary platform 35. Both said platforms are equipped with suitable holes to accommodate the mounting screws i8 and I3 of a pair oi.' terminal connector blocks as shown in Fig. 1 or Fig. 3. By

soonesampnuormmdtnsfemletmwme will engage or disengage the spring contacts of the said blocks. Aligning rods, 4I are suitably mounted in the vertical side members of the statlonaryplattormandheldinplacebyset screws 42. Said rods 4i are of a suitable length to penetrate longitudinal holes 43 in the vertical side members 33 and 43 of the movable platform 34 and thus prevent any nt of contacts upon the engaging of a pair of connector terminal blocks mounted upon said platforms 34 and 35.

Although only limited and specific embodiments of the present invention have been shown and described, it may be modified without departing from the principles thereof and any such modifications, are, therefore, deemed to be within the scope of the invention as defined by the appended claims.

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.

What is claimed is:

1. An electrical connector comprising a pair of generally rectangular shaped insulating blocks, a first multiplicity of flat metallic spring like con tact members disposed at equal intervals along the longitudinal axis in transverse relation thereto of one of said blocks, and a second multiplicity of metallic spring like contact members similarly disposed in transverse relation with respect to the longitudinal axis of the other of said blocks, the contact members associated with one of the blocks being so formed as to electrically engage the corresponding contact members of the other of said blocks on abutment of the corresponding longitudinal sides of said blocks, each of said contact members having a portion thereof exposed for external electrical connection, a transverse raised rib like portion separating adjacent contact members of each of said blocks, and a longitudinal retaining member integral with one end of each said rib like portion on said other block and disposed over the engaging end of the contact members of said other block.

2. An electrical connector comprising; a pair of generally rectangular insulating blocks, a nrst plurality of exposed electrical terminals disposed at equal intervals along the longitudinal axis of one of said insulating blocks, a second plurality of exposed electrical terminals disposed in a similar manner on the other of said insulating blocks, a rst plurality of flat metallic spring like contact members each associated with one of said rst plurality of electrical terminals and extending transversely lbeyond one longitudinal side of said one of said blocks, a second plurality of flat metallic spring like contact members each associated with one of said second plurality of electrical terminals, the contact members associated with one of the blocks being so formed as to electrically engage the corresponding contact members of the other of said blocks on abutment of the corresponding longitudinal sides of said blocks, a transverse'raised rib like portion separating adjacent contact members on each of said blocks, and a longitudinal retaining member integral with one end of each said rib like portion on said other block and disposed over the engaging end of the contact members of said other block.

3. An electrical connector comprising a pair of generally rectangular shaped insulating blocks, a

so attaching a pair of said blocks, the male block nrst multiplicity of flat metallic spring like con asians 7 tact members disposed at equal intervals 'along the longitudinal axis in transverse relation thereto oi one oi said blocks. said contact members extending beyond one longitudinal side of said block, and a second multiplicity of metallic spring like contact members similarly disposed in transverse relation with respect to the longitudinal axis oi' the other oi said blocks, said second multiplicity of contact members being curved at one end and extending at said curved end to one longitudinal edge of said other of said blocks, a multiplicity of transverse rib like portions located on each of said blocks and arranged to separate the adjacent contact members thereon, a connecting means associated with each of said contact members, and a longitudinal retaining member integral with one end of the rib like portions oi said other of said blocks, said longitudinal retaining member being located over the curved ends of said last named multiplicity of contact members and in physical contact therewith.'

whereby a. multiplicity of rectangular openings are provided in the longitudinal side of said other of said blocks into which said rst named multiplicity of contact members oi' said one oi said blocks are adapted to be inserted upon abutment of the corresponding longitudinal sides of said blocks. v

4. An electrical connector comprising a pair of generally rectangular shaped insulating blocks. a first multiplicity of iiat metallic spring like contact members disposed at equal intervals along the longitudinal axis in transverse relation thereto ot one of said blocks. said contact members extending beyond one longitudinal side of said block, and a second multiplicity of metallic spring like contact members similarly disposed in transverse relation with respect to the longitudinal axis of the other of said blocks, said second multiplicity of contact members being curved at one end and extending at said curved end to one longitudinal edge of said other of said blocks, a multiplicity of transverse rib like portions located on each of said blocks and arranged to separate the adjacent contact members thereon, a connecting means associated with each of said contact members, and a longitudinal retaining member integral with one endof the rib like portions of said other of said blocks, said longitudinal retaining member being located over the curved ends of said last named multiplicity of contact members and in physical contact therewith, whereby a multiplicity`oi! rectangular openings are provided in the longitudinal side of said other of said blocks into which said iirst named multiplicity of contact members of said one of said blocks are adapted to be inserted upon abutment of the corresponding longitudinal sides of said blocks, a longitudinal lip integral with one end of the rib like portions of said one of said blocks and projecting therefrom over and beyond the extension of said iirst multiplicity of contact members, said lip being so disposed as to lit over said retaining member upon abutment of said blocks.

5. An electrical connector comprising a pair of generally rectangular shaped insulating blocks, a. iirst multiplicity of at metallic spring like contact members disposed at equal intervals along the longitudinal axis in transverse relation thereto of one of said blocks, said contact members extending beyond one longitudinal side of said block, and a second multiplicity of metallic spring like contact members similarly disposed in transverse relation with respect to the longitudinal axis of the other of said blocks, said second multiplicity of contactmembersbeingcurvedatone endand extending at said curved end to one longitudinal edge of said other of said blocks, a multiplicity of transverse rib like portions located on each ot said blocks and arranged to separate the adjacent contact members thereon, a connecting means associated with each of said contact members, and a longitudinal retaining member integral with one end oi the rib like portions of said other oi blocks, said longitudinal retaining member being located over the curved ends oi said last named multiplicity of contact members and in vphysical contact therewith, whereby a multiplicity of rectangular-openings are provided in the longitudinal side of said other ot said blocks into which said iirst named multiplicity ot contact membersv of said one of said blocks are adapted to be inserted upon abutment oi the corresponding longitudinal sides of said blocks. a longitudinal lip integral with one end of the rib like portions of said one o! said blocks and projecting therefrom over and beyond the extension of said first multiplicity o f contact members. said lip being so disposed as to iit over said retaining member upon abutment oi said blocks, -a series oi! guiding rods projecting normal to the abutting edge of said one oi said blocks and corresponding holes in the abutting edge of the said other of said blocks suitable to receive said rods whereby upon abutment of said blocks their respective contact members cannot be misalisned. A

6. An electrical connector comprising, a pair of generally rectangular shaped insulating blocks, a multiplicity of ilat metallic contact members disposed at equal intervals along the longitudinal axis in transverse relation thereto of one of said blocksI a multiplicity of pairs of metallic spring like contact members similarly disposed on the other of said blocks, each oi.' said pairs of contact members consisting of similar metal strips curved at one end and flat at the other and placed back to back so that the curved portions of each exerts a pressure against the other, a transverse raised rib like portion separating the adjacent contact .members o! each of said blocks, a longitudinal retaining member integral with one end of each said rib like portion on said other block and disposed over the curved ends of the contact members of said other block, corresponding 1ongitudinal sides of said pair of blocks being so shaped that upon abutment of said sides the said multiplicity of iiat contact members of one of said blocks will insert between the curved ends ot the said multiplicity of pairs of contact members oi the other of said blocks.

7. An electrical connector comprising. a pair oi' generally rectangular shaped insulating blocks, a multiplicity of dat metallic contact members disposed at equal intervals along the longitudinal axis in transverse relation thereto of the first of said blocks, said iirst block being so cut away at the top of one longitudinal edge thereof as to leave one end of said multiplicity of transverse contact members free of said block, a multiplicity of pairs of metallic spring like contact members similarly disposed on the second of said blocks, each of said pairs of contact members consisting of similar metal strips curved at one end and iiat at the other and placed back to back so that the curved portions of each exerts a pressure against the other, a transverse raised rib like pogtion separating the adjacent contact members of each of said blocks, said rib like portions on the second of said blocks being elongated so as to extend beyond one longitudinal edge thereof, the

9 extending portions being Joined tgether at their tops so as to enclose said pairs of spring like contact members, said contact members also extending beyond the same longitudinal edge so as to reside within said enclosure, a transverse groove extending from each said raised rib on said first block along the said cut away portion of said block which extends below the contact members thereon, whereby said grooves will receive the lower edges of said rib extensions of said second block upon abutment of said blocks along corresponding longitudinal sides such that said multiplicity of fiat contact members of said irst block will insert between the curved ends of said multiplicity oi pairs of metallic spring like contacts of said second block.

ISAAC L. AUERBACH.

REFERENCES CITED The following references are of record in the 20 tile of this patent:

l0 UNITED s'ra'rss PA'I'ENTS Number Number Name Date Cox Sept. 30. 1884 Case Jan. 24, 1899 Linke Feb. 20, 1906 Hubbell June 6, 1911 Huddleston Nov. 30, 1915 Kinnard Jan. 2, 1934 Gary July 17, 1934 Newman Feb. 25, 1936 Obszarny July 21, 1942 Frank Mar. 2, 1943 Brewer Aug. 10, 1943 Gillentine Nov. 4. 1947 FOREIGN PATENTS Country Date England Jan. 12, 1944

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