Electrical connecting device

April ll_s 1950.

L. L. VERKUIL

ELECTRICAL -CONNECTING DEVICE

Filed April 11, 1947

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ATTORNEY

Patented Apr. 11, 1950

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UNITED STATES PATENT OFFICE

2,503,569

ELECTRICAL CONNECTING DEVICE

Leo L. Verkuil, Tottenville, N. Y., assignor to Edwards and Company, Inc., Norwalk, Conn., a corporation of New York

Application April 11, 19

Claims. (Cl. 1

This invention relates to the construction of electrical connecting devices such as so-called plug connectors, and to plug and socket connecting devices.

One of the objects of this invention is to pro- 5 vide a simple, practical and efficient electrical connecting device that will be simple to assemble or disassemble, particu’arly for purposes of connecting or disconnecting electrical conductors therefrom. Another object is to provide a dev'ce 1θ Of the above mentioned character in which a goodly number of electrical conductors, usually in the form of several cables or groups, may be interrelated therewith in a speedy and simple manner and safeguard against breakage or disruption during subsequent use of the installation. Another object is to provide an electrical connecting device in which the individual or separate parts are of simp’e and inexpensive construction or manufacture and are capable of W rapid and reliable assembly or disassembly. Another object is to provide a pract’cal, strong, and inexpensive plug connector construction ’hat will be well adapted to co-act with a receptacle construction for the intended control of c’rcuits with- ²⁵in the receptacle structure. Another object is to provide a plug and receptacle type of electrical connecting device that will be well adapted to meet varying and hard condit'ons of practical use. Another object is in general to provide an 30 Improved elec'rical connecting device of the above mentioned character, and ether objects will be in part obvious or in part po’nted out hereafter.

The invention accordingly cons’sts in the fea- 3 tures of construction, combinations of elements, and arrangements of narts as will be exe^p’ifled in. the structure to be he’-einaf’er described and the scone, of the application of wh’ch will be indicated in the following c’aims.

In the accompanying drawinn·,, in which is illustratively shown a prefe-red embodiment of my invent’on.

Figure 1 is a top plan view of the plug connector;

Figure 2 is a central vertical sect tonal view of the plug connector, certain parts being shown in elevation, showing it also in position about to be assembled to one possible form of receptacle construction which is shown also .in. vertical section, certain parts being shown in elevation;

Figtre 3 is a bottom plan .view of the plug eon»., nector, substantially as seen along the line 3—3 of Figure 2;

17, Serial No. 740,862

200—51.09)

Figure 4 is a horizontal sectional view as seen along the line 4—4 of Figure 2;

Figure 5 is a top plan view of the receptacle construction as seen along the line 5—5 of Figure 2; and

Figure 6 is a horizontal sec'ional view as seen along the line 6—6 of Figure 2.

Similar reference characters refer to similar parts throughout the several views of the drawing.

Electrical connecting devices are usua’Iy in the form of disconnectable plug and receptacle units to one or both of which one or more electrical conducto's are connected, frequently in the form of a flexible insu’ated cable or multiple insulated conductor sometimes ’mown as a “flexible cord” or “flexib’e cable”; although in the accompanying drawing I have illustrated my invention with resnec’ to a plug-prong type of connector, it is to be understood, as is later pointed out more clearly, my invention is equally applicable to other types of connecting devices such as those employing socket or fema’e types of connector elements instead of p’ong con toe's. It might a’so at this point be noted that, in prior types of constructions, great d’fficulty is met with in adequately accommodating numerous insulated conductors to be related to the device, particularly when they are to be handled in the form of severs¹ cab¹ as, and a frequent and material disadvantage in certa’n nrio” constructions is in the lack of the mechanica¹ protection for the numerous conductors under the stresses and abuses of the use in actual installs t'on. One of the domi5 nant ai^s of this invention is to provide a simple, inexpensive and compact construction in which such disadvantages as those just _no^_e(j _win be overcome in a thoroughly practical and re1'ah’e way.

A’so, in certain tvpes of p’ug and receptacle connector constructions, such as those employed in hospital signa^ring systems, it is desirable to mske nrov’sion for activating ’he signalling circuits connected to the recentac’e in response to disconnection of the plug connector from the receptac’e connector, and a’so to make provision for deactivating such signalling chcui’s where the plug connector is intentionally removed. An-

-.. other object of this invention is. to provide a 0 simple, compact and dependably acting plug connector construction-that will, in a-simple and fool-proof manner,· co-aet with such a receptacle, connector,, particu’arly for insuring the r.est|ra, tion of the recentac’e. elements for /proper co- action with the contacts of Os tftug connector

2,503,569 when the latter is reassembled to the receptacle. Referring to the drawing and considering first the plug connector, the latter, generally indicated by the reference character 9, preferably comprises two separable parts, one a base element 10 (Figure 2) which is preferably made of moldable insulating material and the other a casing element ί ί which can be made of any suitable material preferably non-metallic and hence also non-conductive, such as any moldable resin type of material. The base i 0 which can be made of short axial dimension is preferably of circular cross section and, as will presently be seen, is given a configuration which is simple and inexpensive to produce out of moldable materials like those above mentioned. It carries and supports a suitable number of conductive elements which are constructed to provide any suitable form of devices for attaching electrical conductors thereto and each to provide a connector element such as a contact with which a companion contact element may be engaged or disengaged at will; the conductor-connecting devices are preferably arranged to be accessible from the inside face of the base 10 and the contacts are arranged to be accessible from the outer or rear face and where as by way of illustration they take the form of contact prongs, they may project from and beyond suitable recesses in the base 10.

Conveniently a unitary construction may be employed for each as is better shown in Figure 2, and each may comprise a shank i 3 which is suitably embedded and anchored in the base 10, and this may be achieved during the molding and curing of the latter, and where the shank 13 emerges from the base 10 through the upper or inside face 14 thereof, an upward extension 15 of the shank 13 carries a connector screw IS by which the wire may be secured, and if desired, the part 15 may be provided with side wings I5^aand 15° to better confine the conductor which is sometimes stranded, for proper coaction witn the head of the binding screw 16.

Any desired number of such devices may be employed, preferab’y by grouping them about the central vertical axis of the base 10; in the illustrative embodiment five such devices are shown (see Figure 4). The under or outer face 18 of the base 10 may, if desired, be provided with suitable recesses 19 (Figure 2), one for each shank 13, which may be extended and shaped to give the desired configuration to form one of a pair of separable contact elements, and where as in the illustration, my device is to function as a plug unit with prongs, the shanks 13 may be extended further and beyond the recesses 19 to provide the desired number of prong-like contact elements projecting away from the under face 18 of the base 10, as indicated at 20. The contact portions 20 may be given any configuration and may be resilient or springy for yieldable interlocking engagement with a companion element, the springiness being effective or appropriate whether the element projects beyond the face of the base 10 to form a contact prong or is only of sufficient length to be accommodated in the recess 19 to form a socket or recessed engaging contact or prong.

In the illustrative embodiment the contact prongs 20 project materially beyond the underface of the base 10 in order to co-act with some contacts within the receptac’e structure which in Figure 2 is generally’indicated as a whole by the reference character 30,. and since the· plug connectoi; structure is .to.'ccriact alsp with certain other parts of the receptacle 30, it will be helpful first to describe an illustrative embodiment of the receptacle construction itself. The latter preferably comprises two separable parts, a lower part 31 and an upper part 32, each made of a suitable and preferably moldable insulating material. The lower part 31 comprises a base or mounting part 33 from which extend upwardly a plurality of ribs R of a cross-section as is better shown in Figure 6, terminating in an upper flange-like portion 34, which may be square in horizontal section, to mate with the flange 35 of the upper part 32 which has a top closing wall 36 provided with a number of apertures later described, including apertures shaped and positioned to receive therethrough the plug-prongs 29 when the plug connector is assembled to the receptacle structure as by downward movement of the former relative to the latter as viewed in Figure 2. By the flanges 34 and 35 the upper and lower parts may be secured together as by bolts or screws 37 (Figure 5) and by which also the structure may be mounted in the desired position, as in a mounting plate that otherwise closes over a wall outlet box to which the various conductors, illustratively five in number, are brought.

The parallel-walled spaces between successive ribs R (Figure 6) are extended downwardly in the form of slots in the sides of the mounting part 33 and in five of the six vertical spaces thus provided are mounted contact springs 38 which are provided with an inwardly directed bend 3S^aintermediate of their lengths and at their upper ends terminate in a V-shaped portion 38^b, so shaped for mechanical interlocking or interengagement with a contact prong 20 of the plug connector 9; preferably each contact spring 38 is backed up by a flat spring 39, and each pair of springs 38—39 is secured to the mounting part 33 by a screw 41 (Figure 2) threaded into the mounting part 33 and serving also to secure in position a downwardly extending plate-like connector lug 42 provided with any suitable means such as a screw 43 for connecting a wire thereto^ Springs 38—39 are thus neatly accommodated in the spaces and slots between successive ribs R and the contact spring 38 preferably projects upwardly to terminate just below the top closing wall 36 which is provided with five holes 44 (Figure 5), one for each contact spring 38 whose upper bent end 38^b norma’ly is positioned just about underneath a hole 44.

The five holes 44 and the underlying five contact springs are spaced from each other by about 60°, occupying an arc of about 240°, and as is better shown in Figure 3 the contact prongs 20 are similarly disposed in the above-described base 10 of the plug connector so that when the latter is brought downwardly in Figure 2 on to the receptacle 30, the five prongs in their respective holes 44 and the co-acting shapes of the prongs and the contact springs 38 brings the former into mechanical interlocked relation to the latter, the springs 38—39 yielding radially outwardly during this interlocking action and by their resiliency maintain the contact portions 38^b in good electrical engagement with the prongs 20.

With five conductors connected to the five connectors 42—43, four signalling circuits may be established, one of the conductors being common to all, arid by way of the conductors of a cableconnected to. the .plug p ongs at the binding screws .16, thesQ..circuits may be extended to a push butCori'switch’ bywhich the patient can close·

8,603,669 the signalling circuits. It is desirable to effect an activation of the signalling circuits in the event that the plug connector 9 is accidentally or otherwise removed from the receptacle, and in the illustrative construction, I provide a metal plate 46 (Figures 2 and 5) which can be generally round and which rests in suitable seats or recesses S formed in the upper ends of the ribs R of the lower part 31, being held therein by the under face of ribs R^L which are integrally formed as part of the upper receptacle part 32 and which otherwise are shaped and spaced as are the ribs R above described. This metal plate 46 is so dimensioned (Figure 2) that, with the plug connector prongs removed from the receptacle, the inward bias of the contact springs 38—39 moves them radially inwardly into engagement with the plate 46, thus activating all of the signalling circuits. Replacement of the plug connector 9 causes the plug prongs 20 again to engage the contact springs and force and hold them radially outwardly from the conductive plate 46, and such replacement of the plug connector could be effected by the attendant who answered the activated signals when the. plug connector was initially removed.

It is desirable at times to remove the plug connector and at the same time to deactivate the signalling circuits. In such case I may employ a construction as is better shown in Figure 2 in which there is provided a cam 47 that has five cam parts 47^a projecting into the spaces between the ribs R and in which the five contact springs are mounted, for coaction with the bends 38¹ of the contact springs. The cam 47 has an upper stem 48 that is slidably guided in a central hole 50 in the top wall 36 and it has a bottom stem 5i that is slidably guided in a hole 52 at the bottom of a well 53 in the mounting part 33. Stem St has about it a helical spring 54 which extends into the well 53 and normally biases the entire structure 48—47—5f, which may be made of molded and cured plastic, upwardly to a position where the cam parts 47® are ineffective to cam or hold the contact springs outwardly out of engagement with the contact plate 46.

Accordingly if the cam is in its uppermost position, a position limited by the plate 46 or by the top wall 36, removal of the plug connector 9 permits the contact springs 38 to move inwardly and engage the contact plate 46, thus activating all of the signalling circuits. If thereupon the cam 47 is manually depressed by pushing downwardly on the stem 48 which projects upwardly beyond the top wall 36, the cam parts 47^a are brought into engagement with the bends 38® of the contact springs and force the latter and the backing springs 39 radially outward’y out of engagement with the conductive plate 46.

Suitable means are p~ovided to hold the cam in such depressed position and such means may comprise a flat spring member 56 which is accommodated in the remaining or sixth vertical space or slot (in the 9 o’clock position in Figures 5 and 6) where it is secured as by screw 57 to the mounting part 33 (Figure 2); the spring part 56 extends upwardly beyond the top wall 36, passing through a hole 58 (Figures 2 and 5) in the latter, being bent backwardly upon itself to provide an operating part 56^a and an inwardly projecting stop part 56^b which coacts with an abutment 47^b integrally formed with the cam 47 as an upward extension to provide a top face 47° over which the stop part 56^b rides under the inward bias of the spring 56, thus to hold the cam structure in depressed position against the effort of the compressed spring 54. The part 47^b has a vertical side face 47¹ along which the stop part 56^b engages when the cam is in position above that shown in Figure 2.

The activation of the signalling circuits that results from the removal of the plug connector 9 can thus be undone by manually depressing the stem 48, the vertical face 47*' riding downwardly and along the stop part 56^b until the top face 47° is brought below the level of the stop part 56^b which thereupon moves radially inwardly and thereafter holds the cam in depressed position.

Any given signalling station may thus be made inactive and kept inactive until such time as a plug connector 9 and its associated push button switch are again to be related to the receptacle at that station, and in the construction of the plug connector provision is made to insure the restoration of the parts within the receptacle for proper coaetion. with the plug connector prongs and the circuits connected to the latter. For this latter purpose the base 10 of the plug connector which, as is better seen in Figure 2, is preferably of substantial thickness and strength, is provided centrally, in its own face, with a recess 60 dimensioned so that, when the plug and receptacle are assembled in substantially face to face engagement, the stem 48 can be adequately accommodated therein to the extent that the stem 48 has to project above the top wall 36 when the cam 47 is in uppermost position, a position in which the spring contacts 38—39 are freed by the cams 47® for mechanical interlocking and electrical engagement with the plug connector prongs 20.

As is better shown in Figure 3 and already above described, the plug connector parts illustratively the prongs 20, occupy an arc of about 240°, leaving a sector-shaped space of about 120° whose central axis extends through the 9 o’clock position as seen in Figure 3. In that area, and in the under face of the base 10 is formed or provided, as by molding, a recess 61 whose center line extends along the 9 o’clock radius and whose width in a circumferential direction is somewhat greater than the width of the bent-over and curved operating part 56^a of the member 56 that carries the stop part 56^b, the recess 61 conveniently opening into the peripheral side face of the base ί 0 and being of a depth greater than the extent to which the operating part 56® projects (Figure 2) above the top wall 36 of the receptacle. The inner end wall of the recess 61 is shaped to provide a shoulder 61® and a downwardly and inwardly inclined face 61^b, the latter being of an extent in a radial direction to contact the rounded operating part 56^aas the p’ug connector is moved (downwardly in Figure 2) to assemble it to the receptacle as above described, the inclination or shape of the cam surface 61⁶ acting to resolve the acting forces downwardly (in Figure 2) into, components, one of which is substantially horizontal or in a radial outward direction to thereby swing member 56 against the bias of its spring action radially outwardly (to the left in Figure 2) and thus move the stop member 56^b away from engagement with the top surface 47° of the abutment 47^b, whence the compressed spring 54 is freed to move the cam 47 upwardly and enter the stem 48 into the rec°ss 60, releasing the spring contacts 38—39, which thereupon move radially inward to interlock with the plug prongs 20 which are.by that time completely entered through the holes 44

2,503,669 of the top Wall 36. By that time the operating part 56^a has been brought sufficiently to the left in Figure 2 to become steadied against the shoulder 6i^a which thereafter holds the member 56 and the stop part 56^b to the left of the vertical face 47^f of the abutment 47^b. Should the plug connector 9 thereafter be removed, the spring contacts, freed from the restraint imposed upon them by the plug prongs 20, move radially inwardly to engage the conductive plate 46, the spring contacts being unobstructed by the cams 47^a which are in the uppermost position, a position dependably brought into being and insured by the above described operations that accompany the assembly of the plug connector to the receptacle.

The base iO is preferably molded to have a side face IO^a that is cylindrical for telescopic entry into the casing element (I which also is preferably made of moldable insulating material and is preferably also generally round (see Figures 1, 3 and 4), being internally molded to have a cylindrical surface I i^a along which the base surface 10^a slides as the base part is entered into the casing part, to the extent permitted by a shoulder I i^b (Figure 2) that is preferably of substantial radial dimension to form a strong ledge against which the base part 10 seats and through which thrusts received by the base part are transmitted to the casing part 11.

The end wall I i^c of the casing part 11 is provided with a suitable aperture 11* for the passage therethrough of the conductors that are to be secured to the parts 15—16 (Figure 4), and illustratively the aperture 1 l^f is of elongated or oval shape (see Figure 1) where it is desired to pass therethrough two flexible cables or groups of conductors to be secured and connected to the contact elements at 15—16. The cable or cables, with the parts 10 and 11 disassembled, are first passed through the ho’e 11^{ of t’-e casing part fi, the connect'ons are made at the binding pests 15—16 in the base part P, an-⁷ then the two parts 10 and 11 are brought together as above described to seat the bese pert 10 against the ledge ll^b. Preferably provi-ion is made to prevent re’ative rotary movement between the base part 10 and the casing part II, so as not to twist up the fanned-out conductors that are accommodated in the substantial space within the assembled structure, and for this purpose I prefer to mold a slot or a key-way IO^b in the side wall 10^a at a point 'diametrically opposed to the region where the cam recess 61 is located. That key way IO^b has a fadial dimension equal to that of the ledge 1 P which is interrupted by what may be termed a key 11« (Figures 2, 3 and 4) molded integrally with the casing part II.

As is better shown in Figure 3,1 provide in the periphery of the under face of the base part 10, as by molding, a recess 63 which is of substantial depth and substantial radial dimension, and occupies an arcuate extent of about 300°, thus to terminate short of the cam recess 61 from which the ends of the arcuate recess 63 are separated by barriers 10¹ and 10«, the under-faces of which coincide with the under face, as seen in Figure 2, of the base part 10, that under face in turn being substantially coincident with the plane of the end face or edge of the casing part II.

As is better shown in Figure 2, there is provided in the inside face I i^a of the casing part 11 a groove 1 l^h that is of an arcuate extent substantially the same as that of the recess 63, and for convenience of molding the groove 11¹¹ can extend throughout the entire 360° of the wall ll^a. Its upper edge (Figure 2) terminates in the plane of the bottom of the groove 63 and it may be given any desired cross-section and in the illustration and preferred embodiment it has a cross-section that is just about half of a circle to form a seat in which to receive a split expansible spring ring 64 which in the preferred embodiment is preferably of circular cross-section and is of an arcuate extent, as is better shown in Figure 3, somewhat less than that of the recess 63 in the bottom part 10. One end 64^a of the spring wire 64 is bent inwardly and may be substantially straight, and one terminus of the recess 63 is widened out as at 63^a (Figure 3) to an extent to give ample clearance to the bent end 64^a on each side of the latter.

With this arrangement, the spring locking ring 64 can be inserted into the recess 63, whose outer wall or boundary is part of the inside wall II* of the casing part II, by entering either end of the wire 64 first into the corresponding terminal end of the recess 63, and by compressing the ring and thus lessening its radius, it can be completely injected into the recess 63 and pressed toward the bottom of the recess 63, whence its springiness and tendency to expand enters and seats it into the side recess 1 l^b.

When so seated in the groove 1 l^h, the base part 10 is securely held within the casing part 11 and the ring 64 coacts with the ledge I l^b to substantially uniformly distribute throughout the periphery of the parts various thrusts to which either ma-v be subjected during use of the plug connector.

The barriers 10¹ and 10« (Figure 3) dependably prevent any such insertion of the split ring 64 as would bring any part of it into the cam recess 61, and thus the cam recess 61 cannot be obstructed nor can its proper coaction with the operating part 56^a (Figure 2) be interfered with. The widened terminal end 63^a of the recess 63 (Figure 3) provides adequate space to accommodate the inwardly bent end 64^a of the split ring so that that end 64^a is always accessible, as by the insertion of a suitable tool such as a screwdriver, into the angle between the wall face II» and the bent end 64^a to compress the ring radially inwardly and thus work it out of its seat 1 (^bwhenever it is desired or necessary to take the plug connector apart, as, for purposes of connecting or replacing the conductors that lead to the binding posts 15—16. Moreover the barriers IO^f and 10«, aided by the recess 61, coact with the upwardly projecting operating part 56^a (Figure 2) in achieving the proper relative rotary position of the plug connector 9 with respect to the receptacle when the former is assembled to the latter.

It will thus be seen that it has been provided in this invention a construction in which the various objects above noted, together with many thoroughly practical advantages, are successfully achieved.

As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawing, is to be interpreted as illustrative and not in a limiting sense.