US 2318484 A
Description (OCR text may contain errors)
y ,1 3. w. HERMAN 2,318, 84
CUBE TAP Filed Feb. 17, 1941 2 Sheets-Sheet 1- May 4, 1943. w. P. HERMAN CUBE TAP Filed Feb. 17, 1941 m um i INVENT meg 1 BY M 161? ATTORNEY 2 Sheets-Sheet 2 Patented May 4, 1943 UNlTED STATE ENT .0FFICE 4 Claims.
My present invention relates to electrical multiple service tap devices, and has particular reference to a novel cube tap construction and a novel method of assembly of the parts thereof.
It is the principal object of my invention to provide a cube tap having an integral one-piece resilient body.
It is an additonal object of my invention to provide a cube tap in which the contact prongs may be assembled without use of screws or similar anchoring means.
It is a further object of my invention to provide a novel cube tap and a novel method for mounting the contact prong in the tap, and anchoring the prong in the tap in electrical and mechanical interlocking engagement.
A further object of my invention is to provide a cube tap in which the slots are so arranged that all the outlets can be used simultaneously without interference from adjacent plugs or taps in the wall receptacle.
Another object of my invention is to provide a cube tap in which the body of the tan is shaped to eliminate danger of arcing.
Still another object of my invention is to provide a cube tap which utilizes the resiliency of the rubber body to ensure the desired contacting engagement of the cooperating prongs.
With the above and other objects and advantageous features in view, my invention consists of a novel arrangement of parts and a novel method of assembly more fully disclosed in the detailed description following, in conjunction with the accompanying drawings, and more particularly defined in the claims appended hereto.
In the drawings:
Fig. l is a front elevation of a cube tap embodying my invention;
Fig. 2 is a side elevation of the same;
Fig. 3 is a top view of the same; Fig. 4 is an enlarged section taken along line 4-4 on Fig. 1;
Fig. 5 is an enlarged section taken along line 5-5 on Fig. 4;
Fig. 6 is an enlarged section taken along line 66 on Fig. 5;
Fig. '7 is an enlarged elevation, partly in section, of another form of my invention;
Fig. 8 is a perspective view of one of the vertical contact prongs;
Fig, 9 is a perspective view of one of the trans verse contact prongs; and
Fig. 10 is a perspective view of one of the vertical prongs for the form shown in Fig. 7.
The present application constitutes an improvement over the type of multiple service tap shown in my Patent No. 2,210,215, dated August 6, 1940. These multiple service taps, conventionally referred to as cube taps, are designed to provide three additional places for inserting electrical contact plugs into a wall receptacle. The taps are usually in various forms, one form for example having three contact portions and an exposed set of contact blades for insertion into the wall receptacle, another form having three contact portions and one side fixed to a length of cord lead wire, so that an extension plug is provided which can be plugged into the wall and provides three outlets at a distance from the wall receptacle. Furthermore, in the conventional cube tap, the vertical and transverse blades are in the same plane, so that if two cube taps are in simultaneous use in a conventional wall receptacle, the lower contacting portion of the upper tap and the upper contacting portion of the lower tap will be so close to each other that they could not be used. To eliminate this difiiculty I have provided a novel construction of cube tap in which the transverse and vertical blades are in different planes, so that every outlet provided by the cube tap can be utilized no matter how close to another contact plug or cube tap it is placed in the wall receptacle.
To this end I provide a cube tap ill having a body portion I I which may be of any suitable material, but is preferably molded in one piece of resilient rubber. The body portion l lcomprises outlet portions l2, l3, l4 and [5, the outlet portions l2 and M being positioned transversely on opposite sides of the cube tap, and the outlet portions I3 and 15 being positioned vertically on opposite sides of the tap as shown in Figs. 1 to 3 inclusive.
The portions l2 and M are joined by transverse flat slots I6 and I1 extending through the plug body in spaced vertical parallel relation, as shown in Figs. 2 and 4. The vertical portions l3 and I5 are joined by flat slots 18 and IS in spaced vertical parallel relation, extending through the plug body in a plane at right angles to the slots l6 and I! as shown in Figs. 3 and 5. Referring to Fig. 4, the slots l6 and I! are each provided, adjacent the surface of the plug body H, with restricted slot exit portions 20, which are adapted to frictionally engage the inserted contact plugs and to act as a snuffer against arcing when the contact plugs are withdrawn from the cube tap body. Each of the slots l6 and I1 is provided adjacent its center portion with abutments 2i integral with the plug body and extending inwardly transversely of the slots,
and adapted to maintain the contact blades in proper position within the slots. The slot I6 is provided with recesses 22 adjacent each end of the slot and adapted to receive the ends of the contact blades and an intermediate recess 23, which extends towards and communicates with the vertical slot 19. Similarly, the slot [1 is provided with recesses 24 adjacent each end adapted to receive the ends of the contact blade therein, and an intermediate recess 25 which extends towards and communicates with the vertical slot [8.
Each of the slots l6 and I1 is provided witha contact blade 26 such as shown in Fig.- 9. The contact blade 26 is provided with inturned ends 2! and an intermediate ben-t'portion'28;
which is bent in the same direction as the --ends 21 and approximately to the same depth. The
bent portion 28 may be provided with oppositely disposed cut-out slots 29. fora purpose .hereinafter to be described. Th'e'contact blades 26'.are positioned in the slots l6. and. IT as sh'ownin Fig. 4, with the abutments. 2 l in.each slot maintaining the blade againstthe opposite slot wall with the ends 21 extending. into. the recesses 22 and 24, and the inwardly extending. portions 28 extending into the. recesses 23 and- 25'. By stamping the blades 2Bin.th'e manner shown in Fig.-9', the blades: for the slots I6 and "are interchangeable.
The vertical slots I8 and I9 are designed, in the form illustrated in Figs. 1 to 6. inclusive, to retain an elongated bladewhich will. protrude from the bottom end'of the plug body, ,as shown in Fig. 1,.to form'externalcontact portions tobe inserted into conventional wall receptacles. The slots l8 and IS are providediwitlirestricted exit portions 30' at their upper ends for frictionally engaging, the inserted contact blades in.a manner similar to the portions Zfliin the slots l6. and H, and 'to prevent" arcing or short-circuiting. Adjacent the upper ends of the slots l8" and [9 are recesses 3| adapted to receive ahent portion of the contact blade, and one edge wall" portion of the slot. l9 communicates with the portion 23 in the slot I6, and the opposite edge walllportion of the slot l8 communicateswith the portion 25 in theslot. I'l'.
Positioned in the slots l8 and l9are contact blades 32, shown in Fig.18'. Each blade 32 comprises an outwardly extending contact portion 33 which maybe of the spring; blade type illustrated, in which a portion of the blade is reentrantly bent upon the face of the blade and arcuately'shaped to provide a spring action contact. The upper ends 34 of. theblades are offset, as shown in Fig. 8, and are provided adjacent one edge with struck-up lugs or tangs 35', and the upper ends of the blades are bent inwardly, as at 35. When the blades 32 are positioned in the slots l8 and I9, as shown in Figs. land 6, the upper bent portions 36 enter into the, recesses 3|, the contact portions. 33 extend from the lower end of the slots, and the intermediate portions 34 are so positioned that the struck-up. lugs 35 extend into the recesses 23 and 25 of the slots 15. and H, the lugs 35 engaging the slots 2.9 in the blade 26 and locking therewith inmechanical andelectrical engagement.
It can thus be readily seen that the. blades will be locked in mechanical andjelectrical' engagement in the slots, with the edge of the blade in the slot l9 interlocking with the face of the blade in the slot l6, and the edgev of the blade in the slot l3 interlocking with the face of the blade in the slot IT. The upper offset portion of the blade 34 leaves room in the slot for the insertion of a conventional contact blade in alignment with the outer contact portion 33 without distortion.
In assembly, the blades 26 are first inserted into the slots [6 and I1, either by hand or by other suitable means, and then the longer blades 32 are pulled or pushed into the slots l8 and I9, either by hand or by machine until the blades interlock.
It can thus be readily seen that when the cube tap hereinabove described is pushed into a conventional wall receptacle the transverse contact portions [2 and M will extend laterally from the wall receptacle; so that if a second cube tap or conventional-contact plug is positioned in the samewall receptacle, the various cube tap openings will be free from interference.
Thecubetap of the present invention is simple in construction and easy-,andeconomical to man ufacture and assemble, having a minimum-number of parts. The body is made in one, integral constructionof softrubber, and the various contact blades are retained in position without the use of screws or other types of additional anchoringmeans.
The construction hereinabove describedmay readily be applied to other types ofmultiple'pole receptacles such as shown in Fig. '7, in which a cord lead wire maybe substitutedfon one of the outlet. portions. Inthis form, the plug. body. 31 comprises three; outlet portions 38, 39. and 40 and a cord. receiving portion M. The portion-M is preferably conically, shaped: andgcomprises a cord opening 42- anda recess 43,- into which an integral baifie, 44 extendsto divide-therecess 43 into.two separate channels. divergingtowards the vertical slot portion. The blades 45- which extend into the vertical slotin thisform are illustrated in Fig. 10. Each blade issimilar to the blade 32 except thatit has 'noextended conta ct portion, as shown inFigs. 7 and 10, and the-lower ends are provided. with cord receiving portions 46 adapted to receive the end ofan electrical cord connection 41. If desired, the blades-may be provided withcontact portions extendingfrom the plug; such as the, blade 32, to provide a plug body having outwardly extending contact blades opposite the cord lead connection.
The-use of the above-describedmethodof manufacture and assembly thus provides a multiple service tap with an integral one-piece body of resilient material, which is easy andeconomical to manufacture and assemble, the blades being firmly anchored in the various slots which are designed to eliminate danger of short-circuiting and arcing, and. the tap. being readily adapted to different types of: multiple service tap forms. While in the illustrated forms, the blades are permanently anchored in the cube tap body by the interlocking action of the tangs or lugs 35 and blades 26; however, if desired, additional lugs or tangs may be struck from the surface of the blades in a manner similar to the lugs 35 for imbedding into the body of the cube tap to provide additional anchoring means. Moreover, the use of a resilient tap body ensures a better contacting engagement of the service plug, the entrance slot for the service prong being restricted to permil? the p g b y to exert a resilient contacting and holding pressure on the contacting face of the tap prong.
While I have described specific embodiments of my invention and a specific method for assembly, it is obvious that these are merely illustrative, and that changes in the size and shape of the parts, in the materials used for the parts, their relative arrangement, and in the assembly methods followed, may be made to suit the requirements for different cube tap designs, without departing from the spirit and the scope of the invention as defined in the appended claims.
1. In a cube tap, a one-piece body of molded soft resilient material having a plurality of transverse and vertical contact receiving slots, said vertical slots being in planes at right angles to said transverse slots, each vertical slot communicating with a complementary transverse slot, said transverse slots having integral abutments extending from the outer wall towards the inner walls of said slots, and contacts mounted within said slots, one face of each transverse contact being in electrical and mechanical engagement with one edge of a vertical contact throughthe communicating openings of said slots, said abutments being adapted to maintain said transverse blades against the inner walls of said transverse slots.
2. In a cube tap, a one-piece body of molded soft resilient material having a plurality of transverse and vertical contact receiving slots extending inwardly from the surfaces thereof and through said body, said vertical slots being in planes at right angles to said transverse slots, each vertical slot communicating with a complementary transverse slot, said transverse slots having integral abutments extending from the outer wall towards the inner walls of said slots, and contacts mounted within said slots, one face of each transverse contact being in electrical and mechanical engagement with one edge of a vertical contact through the communicating openings of said slots, said abutments being adapted to maintain said transverse blades against the inner walls of said transverse slots.
3. In a cube tap, a one-piece body of molded soft resilient material having a plurality of transverse and vertical contact receiving slots, said vertical slots being in planes at right angles to said transverse slots, each vertical slot communicating with a complementary transverse slot, said transverse slots having integral abutments extending from the'outer wall towards the inner walls of said slots, and contacts mounted Within said slots, one face of each transverse contact being in electrical and mechanical engagement with one edge of a vertical contact through the communicating openings of said slots, one of said pairs of slots being formed to join to provide a cord receiving passage, and a pair of electrical conducting wires extending into said passage in electrical conducting engagement with one pair of said contacts, said abutments being adapted to maintain said transverse blades against the inner walls of said transverse slots.
4. In a cube tap, a one-piece body of molded soft resilient material having a plurality of transverse and vertical contact receiving slots, said vertical slots being in planes at right angles to said transverse slots, each vertical slot communicating with a complementary transverse slot, and contacts mounted within said slots, one face of each transverse contact having recesses and one edge of each vertical contact having spaced lugs, said lugs entering said recesses to lock said contacts in electrical and mechanical engagement through the communicating openings of said slots.
WILLIAM P. HERMAN.