US2448592A

US2448592A - Plug connector

Info

Publication number: US2448592A
Application number: US490317A
Authority: US
Inventors: Carl F Hart
Original assignee: CARL J FREDERICKSON; PAUL J MUELLER
Current assignee: CARL J FREDERICKSON; PAUL J MUELLER
Priority date: 1943-06-10
Filing date: 1943-06-10
Publication date: 1948-09-07
Anticipated expiration: 1965-09-07

Description

. p 7, 194a. c. F. HART 2,448,592

PLUG CONNECTOR Filed June 10, 1943 INVENTOR.

50 azy/W;

Patented Sept. 7, 1948 UNITED STATES PATENT OFFICE Y t l 2,448,592 '7 i 1 l p PLII'G CONNECTOR Carl F. Hart, Miami, Fla., assignor oir' one-third to Carl J. Frederickson andone-third to Paul J. Mueller, Miami, Fla. l 7. Application June 10, 1943,:Serial n 490,317

This invention relates to a plug connector of the type described in my co-pendingapplication of the same title filed March 14, 1941,.Serial No. 383,428, now abandoned and has for an object to improve the above identified structure by providing stop flanges on the central terminal, and on the conductor of the outer terminal, of the plug member adapted to engage the contact shoes of the contact prongs of the cap member and limit rotation of the cap member in the bayonet joint connection between the cap member and the plug member so'thatthe operator may be assured that good electrical connection has been made when axially turning movement of the cap member ceases during application of the cap member to the plug member.

A furtherobject is to simplify the construction of the above identified structure by. decreasing the number of parts constituting the plug'memher and the cap member. 1

A further object is to improve the anchoring of the contact prongs to the cap member,

A further object is to improve the construction of the guide bar of the bayonet joint connection by increasing the width of a portion of the opening in the plug member ,whichreceives the guide bar of the cap member, andforming the guide bar with a similar portion of increased Width to the end that the plug member and. cap member will be polarized that is the live contact prong will always engage the live side of the electric circuit while the other prong will engage the ground side of the electric circuit.--

A further ob ect is to provide apparatus of this character which will be, formed of a few strong, a

s mple and durable parts, which will be inexpensive to manufacture, and which will not easily get out of order.

With the above and other obiects in view the invention consists of certain noveldetails "of construction and combinations of parts herein after fully described and claimed, it being understood that various modifications may be resorted to within the scope, of the appended claim without departing from the spirit or sacrificing any of the advantages of the invention. v V In the accompanying. drawing forming a part of this specification: r Figure 1 is a longitudinal sectional viewof' a 1 Claim. (01. ire-343i f plugconnector constructed in accordancewith the-invention. 1 i t P i T Figure 2 is a cross sectional View of thelplug connector takenon the line 2-2 of Figure 1. i

I Figure- 3 is a top plan view of the cap member shown in'Figure l, with a portion shown in section taken onthe line 33 of Figure-1.

- Figure ll-is a cross sectional view of the cap membertaken-on the line 44 of Figure 3.

Figure 5 isa bottom plan view of'the plug member shown inFigure'l. y a

igure'fi is adeta'il perspectiveview of one of the conductors for terminals of the plug member showing the stop fiange thereof. r l 1 Figure '7 is a detailperspective view of one of the contact prongs of the cap member showing theoutwardly bent lower end having anopening to, receive: thematerial of the cap, member to form-an anchorp. g I

Figure 8 is a top 'plan view of'amodified form of cap member with a portion of vthe icontact prongsand a portionv of theguide bar-shown in section: y 1 I Figure 9 is a'detail perspective view of one of the modifiediforms of contact prongs shown in-Figure 8. i J -Figure'10; is a bottom, plan view of amodified formof plugmember, drawn to reduced scale; Referring now to thedrawingiorming apart of this specification, the cap member of the plug connector comprises a body IE! formed of insulatingmater-ial having a reducedtubularend H adapted to receive anelectric. cord I2 of the usual type, carrying two circuit wires l3. A short substantially cylindrical guide bar l'lp ro je cts from ,the axis of the body opposite the reducedend and the top faceof the body '15 provided with a countersink I8 at the base of the guide bar. The guide bar is provided with diametrically oppositely disposed fiat faces 19, see Figure 2. 'A pair of contact prongs 20, one of which is shown in Figure '7, extends longitudinally on the'fiat faces of the guide barfl Each contact prong is formed with an outwardly bent anchoring end 2! adapted to be-embe'dded in the material of the cap member and provided with an opening 22' to receive the material of the cap member for locking the contactprong in place. Each contact prong is provided witha threaded opening 23 to receive a respective screw '24, see Figure 1, for attaching one of the circuit wires i3 to the prong. Each prong at the upper end is provided with a contact shoe 24' formed preferably by bending the upper end of the prong outwardly, downwardly and then inwardly, see Figure 7.

The plug member comprises a body 25 formed of insulating material having a cylindrical opening 26 extending from the upper end to nearly the lower end of the body, there being a guide opening 21 formed axially in the lower end of the body communicating with the opening 25 and of sufficient diameter to permit the guide bar I! being passed theret hrough into the opening 26. The bottom face of the body is concave as shown at 28 so that the guide bar may be easily guided into the opening 21.

The opening 21 is provided with diametrically oppositely disposed

recesses

29 and 30, see Figure 5, which coact with the opening in forming a bayonet slot. When the guide bar H is brought. into registration with the opening 21, the cap member may be rotated until the shoes 24 of the contact prongs 20 register with the

recesses

29 and 30 whereupon the cap. member, by rectilinear movement, may be thrust against the plug memher to permit the guide bar and shoes of the contact prongs entering the opening 26 of the plug member. The-reupon the cap member is turned axially to dispose. the. shoes 24' of thecontact prongs out of register with the recesses 29; and 30 so that the contact prongs cannot be accidentally retracted butv must be again given a quarter turn in a retrograde direction to be brought into register with the

recesses

29 and 30 before the cap member and the. plug member can be disassembled. l

Preferably the recess 30 is of greater width than the recess 29- and one of the contact. shoes 24% is of greater width than the other contact shoe. This construction polarizes the bayonet slot since the wider shoe must be brought into register with the wider openingw'before the plug connector can be asembled. The purpose or this is to connect the live contact prong of the plug connector with the live side of the electric circuit while the other prong will engage the ground side of the-electric circuit.

A pair of conductors 3|, one of which is shown in Figure 6, is disposed diametrically opposite each other in the opening 26. The lower end of each conductor is provided with an arcuate contact head 32 adapted to engage the shoe 24 of a respective contact prong 20. The contact head is provided with a stopflange 33 which extends radially in the opening 26 when the contact head 32 extends along the cylindrical wall of the opening, see Figure 2, The stop flanges 33 are disposed out of alignment with each other on opposite sides of the axis of the plug member. Consequently when the guide bar I! and the shoes of the contact prongs are passed into thelopening 26 of the plug member through the bayonet joint and given a part revolution the. contact shoes will engage respective stop flanges 33 and halt rotation of the cap member. The operator is then assured that the shoes are in good electrical contact with the arcuate heads 32' and with the stop flanges 33 of the conductors.

One of the conductors 3| is provided with a hook at the upper end adapted to engage over the upper end of the plug member. An outer cylindrical contact 35 of the usual screw threaded type 4 is sleeved on the plug member and has an electrical contact with the hook 34.

The other conductor 3| is provided with a resilient inclined free end 36 which extends radially along the upper end of the body to form the central terminal or contact of the plug connector.

Both conductors 3| are wedged firmly in place in the opening 26 of the plug member through the medium of a wedge member 31 having an opening 38 to permit the central contact 36 to be exposed exteriorly of the wedge member. The wedge member is provided with a flange 38' which clamps the outer cylindrical contact 45 firmly against the upper end of the plug member 25.

As shown in Figure 4 the cap member ID is provided with passages 39 through which the circuit wires 13 enter the countersink 18 for application to the screws 24.

A modified form of cap member is shown in Figure 8 in which the only difierence over the cap member heretofore described is that the conductor prongs 40 are not imbedded in the material of the cap member but rather are equipped with base flanges H which extend along the bottom of the countersink l8 and are secured to the cap member by screws 42 passed through openings 43 in, the base flange 4|. An additional screw M is, passed through an opening 45 in the base flange to receive a circuit wire which projects from the respective passage 39.

It: is not essential that the recesses 29 and 3B of the opening, 21- inv the plug member be of re spcctivelydifierent widths. As shown in Figure 10 both recesses 46 may be formed of identical width.

Since the operation of the parts has been described as the description of the parts progressed it is thought the invention will be fully understood without further explanation.

What is claimed is:

In an electric plug connector, a plug body having a centrally disposed cylindrical opening extending inward from the inner end thereof with the opposite end provided with an annular flange having a concave under surface and with a centrally disposed opening in axial alignment with and communicating with said cylindrical opening, said opposite end having diametrically opposedrecesses at the sides of said centrally disposed opening, a pair of diametrically opposed conductors extending lengthwise in said cylindrical opening and positioned against the Wall of said plug body, arcuate contact head portions extending circumferentially from said conductors and each terminating in a plane corresponding with the inner ends of the recesses, stop flanges extending radially from said head portions, a plug wedged in said cylindrical opening securing said conductors against the walls of the plug body, one of said conductors extending through said wedge plug and terminating in a free end portion forming one external contact, the other of said conductors extending out of the opening and over the edge of the plug body, a threaded sleeve positioned over the said plug body anchoring the end of the conductor extending over the edge of the. plug body providing another external contact, a plug cap having a guide bar with oppositely disposed. flat sides projecting at the inner end adapted to be inserted in the centrally disposed opening in the saidopposite end of the plug body, said cap having a counterbore around the base of the guide bar, contact prongs with shoes at the outer ends thereof positioned against the flat sides of the guide bar, said contact prongs 5 and shoes adapted to enter the recesses in the said opposite end of the plug body with the guide bar in the centrally disposed opening, said cap having a neck of reduced diameter on the end opposite to the end carrying the guide bar, and means connecting wires of an electric cord entering the cap through the neck to the contact prongs in the said counterbo-re.

CARL F. HART.

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

Number Kostal Mar. 3, 1942