US2728897A

US2728897A - Electrical plug receptacles

Info

Publication number: US2728897A
Application number: US347057A
Authority: US
Inventors: Roland E Dupre
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-04-06
Filing date: 1953-04-06
Publication date: 1955-12-27
Anticipated expiration: 1972-12-27

Description

Dec. 27, 1955 Filed April 6, 1953 R. E. DUPRE ELECTRICAL PLUG RECEPTACLES 2 Sheets-Sheet l aga 3l 35 INVENTOR ROLAND E. DUPRE ATTORNEY 2 Sheets-Sheet 2 Filed April 6, 1953 INVENTOR ROLAND a. DUPRF.

ATTORNEY United States Patent ELECTRICAL PLUG RECEPTACLES Roland E. Dupre, Fiskdale, Mass.

Application April 6, 1953, Serial No. 347,057 Claims. (Cl. 339-164) This invention relates to improvements in receptacles -for receiving the plugs of electrical attachments and has particular reference to the provision of a novel and inexpensive receptacle wherein only the portion most susceptible to wear may be readily nterchanged or replaced without having to discard the entire receptacle.

lOne of the principal objects of the invention is to provide a receptacle of the above character whereby only the effective plug receiving portion or part thereof most susceptible to wear may be readily interchanged or replaced in a simple and ellicient manner without having to discard the entire receptacle and without disturbing the connection thereof with the main line circuit and with little or no danger of receiving electrical shock during said interchanging.

Another object is to provide a receptacle of the above character which is exceedingly simple in construction and which may be readily assembled with standard prior art bracket boxes.

Other objects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings, and it will be apparent that many changes may be made in the details of construction and arrangement of parts without departing from the spirit of the invention as expressed in the accompanyingclams. I, therefore, do not wish to be limited to the exact details of construction and arrangement of parts shown and described as the preferred form only has been given by Way of illustration.

Referring to the drawings:

Fig. 1 is a face View of the receptacle embodying the invention;

Fig. 2 is a side elevational view of said receptacle diagrammatically illustrating its position of use internally of a conventional bracket box;

Fig. 3 is a bottom plan view of the receptacle showing the bottom plate removed and the adjacent portions of the bracket in cross section;

Fig. 4 is a sectional view taken as on line 4-4 of Fig. l and looking in the direction indicated by the arrows;

Fig. 5 is a sectional view taken as on line 5-5 of Fig. 1 and looking in the direction indicated by the arrows;

Fig. 6 is a side elevational view of a terminal contact vplate of the device embodying the invention illustrating an initial step in its fabrication;

Fig. 7 is a top View of the device shown in Fig. 6;

Fig. 8 is a perspective View of the device illustrated in Figs. 6 and 7 showing it in connected relation with a terminal; and

Fig. 9 is a perspective view of a contact blade unit of the device embodying the invention.

Referring more particularly to the drawings wherein like characters of reference designate like parts throughout the various views, the device embodying the invention comprises a main housing 10 preferably formed of Bakelite, plastic, or other non-conductive material. The housing 10 is adapted to receive a plug receptacle 11 which is dimensioned to tit fairly freely internally of said housing. The housing is provided with a tongue 12 .shaped to extend within a groove 13 formed in one side of the receptacle to polarize said receptacle and housing and thereby assure proper assemblage.

2,728,897 Patented Dec. 27, 1955 The main housing 10 is provided, in the opposed side walls thereof, with slots 14 and 15 having their respective inner walls cut away, as illustrated at 16 and 17, to form openings to communicate with the interior of the housing.

Internally of the slots 14 and 15 there is positioned terminal plates 18. The terminal plates 18, as shown in Figs. 6, 7, and 8, are formed of suitable conductive metals, such as brass, beryllium copper, or the like and comprise a main portion 19 formed with a plurality of slightly indented channel-like portions 20 each having a knurled or corrugated surface. Formed integrally with the main por tion 19 is a tongue 21 having its side surface knurled or corrugated, as illustrated at 22. The channels 20, as shown in Fig. 8, are adapted to receive the bared terminal 23 of a main line wire 24 having an insulated covering thereon of the convention type. The terminal 23 in this instance is placed inwardly of the central channel 20 and the tongue 21 is folded over into intimate binding engagement with the terminal 23 to cause the knurled or corrugated snrface thereof and the knurled or corrugated surface of the channel 29 to firmly hold the terminal 23 in said terminal plate. One such terminal plate is attached to each of the main line wires and each is positioned within the respective slots 14 and 15. The terminal plates, as shown in Figs. 3 and 4, are controlled dimensionally so as to frictionally tit within the slots with the tongue portions 21 thereof extending through the

openings

16 and 17. Due to the fact that the terminal plates 18 are formed of metal such as brass or beryllium copper, the said tongues 21 when bent to clamp the terminals 23 therebetween, will spring back slightly adjacent the free end thereof and will be free to yield slightly when pressure is exerted thereon.

The plug receptacle 11 has a recessed central area 25 and opposed raised

areas

26 and 27. The said raised areas have their outer surfaces shaped to taper inwardly to centrally disposed spaced

slots

28 and 29, as shown in Fig. l. The

respective slots

28 and 29, as shown best in Figs. 3 and 4, communicate with inner

open areas

30 and 31, each having inner

solid walls

32 and 33 extending throughout the length thereof and outer walls 34 and 35 which are cut away centrally to form

openings

36 and 37. The respective

inner walls

32 and 33 are provided centrally thereof with solid outwardly extending spacer portions 38 and 39 of a length slightly less than the width of the

respective openings

36 and 37 and which protrude slightly outwardly of the plane of the inner surfaces of the outer walls 34 and 35.

Contact blade units 40, such as shown in perspective n'Fig. 9 are formed so as to have a central contact portion 41, angularly disposed

end portions

42 and 43 and outwardly

angled blade sections

44 and 45 disposed substantially parallel with the contact portions 41. Each blade section has a

deflected portion

46 and 47 adjacent the end thereof. The units 40 are so dimensioned as to lit inwardly of the

open areas

30 and 31 with the central contact portions 41 overlying the outer end surfaces of the respective spacer portions 38 and 39 and with said deflected

end portions

46 and 47 each communicating with a

respective slot

28 and 29 formed in the upper'or top wall of the receptacle, see Fig. 3. The central contact portions 41 of the contact blade units 40, when the receptacle is positioned internally of the main housing 10, as shown in Figs. 3 and 5, are adapted to contact the respective adjacent side surfaces of the tongues 21 of the terminal plates 19 and due to the slight yielding characteristics of said tongues as described above will have a frictional electrical contact therewith. A plate 48 of plastic or other non-conductive material is shaped to overlie the bottom of the main housing 10 and plug receptacle 11. A Abracket 49 having a central portion 50,

side portions 51,' and outwardly extending tongues 53 is secured to the housing by rivets or the like 54 with the central portion overlying the plate 48 and the side portions 51 lying within recessed areas 52 formed in the end Walls of the housing. The receptacle 11 is held in assembled position in the housing 10 with the central contact portions 41 in electrical contact with the tongues 21 of the terminal plates 18 by a screw 55. The screw is provided with an enlarged head 56 having an internally threaded bore 57 adapted to receive the connection screw 58 of a conventional receptacle plate 59, as shown in Fig. 2. The screw 55 is adapted to be threaded through a threaded opening 60 formed in the central portion Si) of the bracket.

Prior to placing the receptacle internally of the housing 10 the screw 55, as shown in Figs. 2 and 5, is provided with a washer 61 dimensioned to overlie the undersurface of the top wall portion of the receptacle. The washer is forced into mechanically locked relation with the screw so as to retain its position thereon when the screw is threaded internally of the threaded opening 60 in assembling the receptacle in the housing 10.

The deected ends 46 of the contact blade 40, as shown in Fig. 4, are adapted to guide the prongs 62 of a conventional plug 63 into proper frictional electrical Contact with said contact blades.

When the device is being assembled the terminal plates 18 having their tongue portions 21 in partially bent position are first placed in the respective slots 14 and 15 of the housing 10. These are placed inwardly of the slots 14 through the underside thereof and the said slots are controlled as to depth so as to properly locate the position of said terminal plates in the side walls of the housing.

The base plate 48 is then placed over the lower side of the housing and the said housing and base plate are positioned within the bracket 49 with the respective side portions 51 of the bracket fitting within the recessed sides 52 of the housing. The end walls of the housing 10 are provided with openings 64 which are aligned with similar openings 65 formed in the sides of the bracket. Suitable rivets having enlarged heads 66 are placed through said aligned openings and the respective outer ends thereof are headed over to secure the housing to the bracket.

The bared ends 23 of the main line wires 24, as illustrated in Figs. 5 and 8, are then placed between the portion 19 and the tongue 21 of the terminal plates 18 and pressure is exerted on the tongue portions 21 an amount sufficient to position them and the respective channels of the portion 19 in binding, gripping relation with said bared ends 23. It is pointed out that one of the main line terminals 24 is secured to one terminal plate and the other is secured to the other terminal plate and that the cover plate 43 is cut away, as illustrated at 69, to provide clearance vvfor attachment of the main line terminals 24 with the said terminal plates 18.

The contact units 40 are then placed within the respective open Vareas and 31 of the plug receptacle 11, as shown in Fig. 3, with the contact portions 41 thereof overlying the inner supporting blocks 38 and 39 and extending outwardly of the

respective openings

36 and 37.

The plug receptacle 11 having the contact blade units positioned therein is then placed internally of the housing 10 and is secured therein by the screw 55 as specified above. The screw is of a length sufficient to permit the central contact portion 41 of the contact blades 46 to be moved out of engagement with the respective terminal plates 18 to which the main line wires 24 are connected prior to having the threaded portion of the screw become disengaged from the threaded opening 60. This backing out of the receptacle 11 to disengage its ycontact portions with the terminal plates 18 is brought about by the washer 41 which is mechanically connected to the screw as previously described. The washer 61, due to its` mechanical connection with the screw will permit the screw to be rotated but will not allow they screw -to lback outwardly of the washer. Therefore, when the screw 55 is backed out of the opening the washer 61 will cause the receptacle 11 to also back outwardly of the housing. The length of the screw is such that this backing out of the receptacle will be of an amount sufficient to disengage the contact portions 41 of the contact blade units 40 from the terminal plates 18 and thereafter allow one to manually remove the plug receptacle from the housing without danger of receiving an electrical shock and possible injury. This arrangement allows the plug receptacles to be readily removed and interchanged when they become worn and does not disturb the connections of the main terminals 23 with the terminal plates 18.

It is further pointed out that this greatly reduces costs in devices of this character in that only the parts which are susceptible to wear must and can be replaced.

The tongues 53 of the bracket 49 are secured to a conventional outlet box 67 by conventional screws or the like 68. It is quite obvious that when changing the plug receptacle 11 neither the bracket 51 nor the housing 10 have to be removed from the outlet box.

It is further pointed out that the plug receptacle 11, as well as the housing 10 and the plate 48 are all formed of plastic or other suitable insulation material. The terminal plates 18 and contact units 40 are formed of brass, beryllium copper, or other suitable conductive metal.

When the plug receptacle 11 is placed inwardly of the housing 10, the said central contact portions 41 of the contact blade units 40 automatically electrically engage the adjacent tongues 21 of the terminal plates 18 and are held in this relation when the screw 55 is properly tightened. y

From the foregoing description it will be seen that simple, efficient and economical means have been provided for accomplishing all of the objects and advantages of the invention.

Having described my invention I claim:

1. A device of the character described comprising a main housing having a slot in each of the opposed side walls thereof, an opening in the inner side wall of each of the slotted walls communicating with the interior of the housing, a terminal plate in each of said slotted walls with a portion thereof extending into the adjacent opening, a plug receptacle in the housing, said plug receptacle having an upper wall and spaced inner open areas, said open areas each having inner and outer walls, Isaid outer walls each having an opening therein, a contact blade unit in each open area having a part thereof extending through the respective openings in the outer walls of the receptacle and engaging the respective portions of the terminal plates in the openings in the inner walls of the housing, said plug receptacle having spaced slots in the upper wall thereof each communicating with the contact blade units and having an opening therein, a cover plate overlying the underside of said housing and receptacle and having an opening therein, a bracket having a A portion overlying the cover plate and having a threaded opening therein in alignment with the opening in said cover plate, a connection screw extending through the opening in the upper wall of the plug receptacle and means on said screw beneath said upper wall and adjacent thereto for retaining the head of the screw in intimate relation with the upper wall of the receptacle,

' said screw extending through the opening in the cover plate and being threadedly connected with a threaded opening in the portion of the bracket overlying said cover plate.

2. A device of the character described comprising a main housing having a slot in each of the opposed side walls thereof, an opening in the inner side wall of eachk of the slotted walls communicating with the interior of the housing, a terminal plate in each of said slotted walls with a portion thereof extending into the adjacent opening, a plug receptacle in the housing, said plug receptacle having an upper wall and spaced inner open areas, said open areas each having inner and outer walls, said outer walls each having an opening therein, a contact blade unit in each open area having a part thereof extending through the respective openings in the outer walls of the receptacle and engaging the respective portions of the terminal plates in the openings in the inner walls of the housing, said plug receptacle having spaced slots in the upper wall thereof each communicating with the contact blade units, said upper wall having an opening therein, a cover plate overlying the underside of the housing and the plug receptacle therein, said cover plate having an opening therein, a bracket having side portions secured to the respective ends of the housing and having an intermediate portion overlying the undersurface ofv the cover plate, said portion of the bracket underlying said cover plate having a threaded opening therein in alignment with the opening in the cover plate, a screw extending through the opening in the upper wall of the receptacle and having a relatively long threaded portion extending through the opening in the cover plate and threaded opening in the portion of the bracket underlying said cover plate and means on said screw beneath the upper wall of the plug receptacle which, when the screw is threaded outwardly of the opening in the portion of the bracket plate underlying said cover plate, will cause said plug receptacle to move outwardly of the housing, said screw being of a length sucient to permit the part of each of the blade units extending through the openings in the outer walls of the plug receptacle to move out of electrical contact with the portions of the terminal plates extending into the openings in the inner slotted walls of the housing prior to having the screw become disengaged from the threaded opening in said portion of the bracket underlying the cover plate.

3. A device of the character described comprising a main housing having slots in each of the opposed side walls thereof, an opening in the inner side wall of each of the slotted portions communicating with the interior of the housing, a terminal plate in each of said slotted walls having a portion thereof extending into the adjacent opening, a plug receptacle in the housing, said plug receptacle having an upper wall with spaced slots therein and spaced inner open areas with which said slots communicate, said open areas each having inner and outer walls, said outer Walls each having an opening therein, a contact blade unit in each open area, each unit having a resilient blade portion communicating with a respective slot in the upper wall of the plug receptacle and having a part extending through a respective opening in the outer Wall of said receptacle and engaging the portion of the terminal plate in the adjacent opening in the inner wall of the housing and having an opening therein, a cover plate overlying the underside of said housing and receptacle and having an opening therein, a bracket having a portion overlying the cover plate and having a threaded opening therein in alignment with the opening in Asaid cover plate, a connection screw extending through the opening in the upper wall of the plug receptacle and means on said screw beneath said upper wall and adjacent thereto for retaining the head of the screw in intimate relation with the upper wall of the receptacle, said screw extending through the opening in the cover plate and being threadedly connected with a threaded opening in the portion of the bracket overlying said cover plate.

4. A device of the character described comprising a main housing having side walls with continuous uninterrupted outer surfaces, said side walls each having a slot extending inwardly of an end edge thereof, the inner surface of each side wall having an opening therein of less width than the slot communicating with the adjacent slot and with the interior of the housing, a terminal plate having a portion of substantially the Width of the slot tted in each of said slots and having a superimposed portion thereof of less width having a relatively flat surface extending into the adjacent opening, said terminal plate having means between said superimposed portions for locking an electric lead therebetween, a plug receptacle in the housing, said plug receptacle having an upper wall and spaced inner open areas, said open areas each having inner and outer walls, said outer walls each having an opening therein aligned with the respective terminal plates, intermediate solid spanner portions on each inner wall in said receptacle having end surfaces aligned with the respective openings in said outer walls and protruding slightly inwardly of said openings, said end surfaces each having a slot extending transversely thereof, a contact blade unit in each open area and having an intermediate part thereof lying within a respective transverse slot and a part extending through the respective openings in the outer walls of the receptacle and engaging the respective portions of less width of the terminal plates in the openings in the inner walls of the main housing, said plug receptacle having spaced slots in the upper wall thereof each communicating with the inner open areas of said receptacle and with the contact blade units in said areas and means for detachably securing said plug receptacle in said housing.

5. A device of the character described comprising a main housing having spaced side walls each having a slot extending inwardly of an end edge thereof and disposed intermediate the outer and inner surfaces of said side walls, each of the inner surfaces of said side walls having an opening of a width less than the width of the slot extending inwardly of the slot in said wall and communicating with the interior of the housing, terminal plates each having a relatively at portion of a width substantially equal to the width of the slots fitted into each of said slots and having a superimposed portion of less width having a relatively flat surface extending into the adjacent opening and lying substantially in the plane of said opening, means between said superimposed terminal portions for locking an electrical lead therebetween, a readily removable plug receptacle in said housing, said plug receptacle having an upper wall with two pairs of spaced slots extending therethrough with each of said slots communicating with an inner open area, said areas being divided with respect to each other by an inner wall and each having an outer side wall, said outer side walls each having an opening extending through the intermediate portion thereof communicating with one of each of the respective pairs of open areas, said inner wall having solid spanner portions of a width less than the respective openings in said outer walls and each having an end surface aligned with and extending slightly into the respective openings in said outer side walls, said end surfaces each having a slot extending transversely thereof, a pair of contact blade units each having an end portion extending within one of each of the respective pairs of open areas and each having a relatively at intermediate part lying within the transverse slot of a respective solid Spanner portion and engaging the respective relatively fiat side surface portion of less width of the terminal plates in the adjacent openings in the inner walls of the main housing so as to have side surface electrical contact therewith and means for detachably securing said plug receptacle in said relation in said housing with said side surface contact portions permitting said plug receptacle to be removed from the housing without disturbing the electrical lead connections with the terminal plates.

References Cited inthe le of this patent UNITED STATES PATENTS 913,160 Pride Feb. 23, 1909 1,982,077 Spencer Nov. 27, 1934 2,239,653 OBrien Apr. 22, 1941 2,452,932 Johnson Nov. 2, 1948 2,671,204 Hubbell Mar. 2, 1954 2,688,735 Hubbel Sept. 7, 1954