US 3742424 A
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Description (OCR text may contain errors)
[ June 26, 1973 United States Patent [191 Startin .K RFAS 64642 66667 99999 11111 NMWS 13374 99579 ,3 99 36 32833 w w w a 33333 a P  Filed:
Primary Examiner-Marvin A. Champion Assistant Examiner-Robert A. Hafer Attorney-William J. Keating Appl. No.: 236,722
 Foreign Application Priority Data Apr. 15, 1971 Great Britain.......... 9,558/71 ABSTRACT  U.S. CI. 339/14 P, 339/62, 339/156 R,
339/211 H0lr 3/06 51 Int. 58 Field of Search 339/14 R, 14 P, 36, An electrical connector assembly comprising first and d releasably matable electrical connectors, each secon elect rical connector including a housing of electrically insulating material and a contact of electrical] y condu'ctive material.
3,519,977 Swearingen........................... 339/36 1 Claim, 7 Drawing Figures ELECTRICAL CONNECTOR ASSEMBLY The present invention relates to an electrical connector assembly of the type in which two electrical connectors are releasably connected together.
Domestic connector assemblies are known in which ;a male or plug connectorhaving tab contacts extending from an insulating housing, mates with a socket con nector in which tab receptable contacts for receiving the tabs of the plug connector are positioned in cavities in the insulating housing of the socket connector.
For safety reasons, and particularly where connectors are to be used with domestic appliances, it is an advantage if no live parts of the connector can be accidentally touched when the connectors are disengaged one from the other.
According to the present invention, an electrical connector assembly comprises first and second releasably matable electrical connectors, each electrical connector including a housing of electrically insulating material and a contact of electrically conductive material, the contact of the first connector having a contact part in the form of a tab, an edge at least of the tab extending within a cavity formed in the front mating surfaceof the first connector housing, the edge extending longitudinally of the cavity and being accessible for electricalcontact with a complementary tab receptacle only from the mating surface of the first connector housing, the contact of the second electrical connector having a contact part in the form of a tab receptacle, the tab receptacle being arranged in a housing part complementary to the cavity and extending in the mating direction from the second connector housing, the
. housing part having a slot for permitting access by the tab edge to the tab receptacle, the housing part of the second connector being received in the cavity of the first connector housing and the tab edge'engaging the I tab receptacle, and relative movement of the first and second connectors apart causing the disconnection of the electrical contacts before the separation of the housing part from the cavity.
In a preferred embodiment, three cavities are provided in the first connector housing, the cavities being arranged at irregularly spaced locations around a central axis of the first connector, a major portion of one edge of a tab extending into each cavity, the tabs being arranged radially with respect to the central axis, three housing parts being provided on the second connector, each containing a tab receptacle and arranged for mating engagement with a cavity, a slot in each housing part being arranged radially with respect to the central axis of the second connector for permitting electrical engagement between the tabs and tab receptacles.
Preferably, one contact of the first connector is located nearer the front mating surface than the remaining contacts which ensures that an earth contact can be made first and broken last during assembly and separation of the connector assembly.
An embodiment of the invention will now be described, by way of example, reference being made to the Figures of the accompanying drawings, in which:
FIG. 1 is an end view towards a mating surface of a male connector;
FIG. 2 is a cross-section on the line II-II of FIG. 1;
FIG. 3 is a perspective view of the connector of FIG. I with a part removed to reveal two contacts in the connector housing;
FIG. 4 is a perspective view of a female connector with a part removed to reveal two contact receptacles in the connector housing;
FIG. 5 is a cross-section through the connector of FIG. 4;
FIG. 6 is an end view of a base member forming part of the connector housing of the connector of FIG. 4; and
FIG. 7 is a cross-section on the line VII-VII of FIG. 6.
An electrical connector assembly comprises a first male connector 1 and a second releasably mating female connector 2.
As shown in FIGS. 1 to 3, the male connector 1 includes a moulded housing 3 of electrically insulating material and three in-moulded contacts 30 of electrically conductive material. The housing 3 has a body 4 having a front mating end 5 and an opposite rear end 6. A flange 8 extends around the front end 5 and has two through apertures 9 for receiving fasteners (not shown).
As shown in dotted lines in FIG. 1, the body 4 has three irregularly spaced branches 10 which extend outwardly from a central axis. A substantially identical cavity 12 is formed in each branch 10, which cavity 12 extends rearwardly into the branch 10 from the front end 5 and includes an abutment 11.
A central bore 14 extends forwardly from the rear end 6 and communicates with an annular passageway 20.
Each contact 30 includes a forward contact part in the form of a tab 32 and a trailing connector portion 34. The contact tab 32 is formed from sheet material folded over on itself along an edge 36 to form a double thickness layer. The layer 39 adjoins at its trailing end, as seen in FIG. 3, a transition portion 38, which tapers to the connecting portion 34. The connecting portion 34 is of reduced width when compared to the width of receptacles 130 made of electrically conductive matethe contact tab 32. A hole 43 extends through the connecting portion 34. The remaining layer 37 of the double thickness layer, is bent through to form a flange 42. Three holes 44 extend through said flange 42 and help to key the contact 30 in the moulded housing 3. The leading end of the edge 36 is formed with a chamfer 45.
The three contacts 30 are each so positioned in the housing 3 adjacent an abutment 11, that a major portion of the edge 36 of each contact tab 32 extends into a respective cavity 12 radially with respect to the central axis of the connector I. The end of a cable 52 extends into the central bore 14 and wires 50 from the cable 52 extend through passageway 20 and into the holes 43 in each connecting portion 34 and are maintained by any known means such as soldering to the connecting portion 34.
One contact 30, in this case the uppermost, as seen in FIG. 3, is located nearer the front mating end 5 than the remaining contacts 30. This is'the earth contact which is thereby made first and broken last when the connector I is assembled to the connector 2.
Referring now to FIGS. 4 to 7, the female connector 2 comprises an insulation housing including a base member 103, a clamp 104 and a cover 105 all of electrically insulating material and three female contact tab rial.
The base member 103 includes a platform 108 from which extends in a forward mating direction, three housing parts 109. Each housing part 109 is unequally spaced about a central axis, and each part 109 has a radial slot 110 extending from a front surface 111 rearwardly to the platform 108. Three spaced peripheral wall members 1 12 extend rearwardly from the platform 108, which wall members 112 partially surround a member 114 of substantially T cross-section. Diametrically opposed latching members 123 are formed in two of the wall members 112. The member 114 extends rearwardly from the platform 108, the stem 119 of member 114 stopping short of the cross-piece 120. Two elongated apertures 121 extend through the crosspiece 120.
The cover 105 is tubular and has an opening at each end. The cover 105 fits over the rear surface of platform 108 to enclose wall members 112 and the member 114. The cover 105 is releasably attached to the base member 103 by means of the latching members 123 which co-operate with apertures (not shown) in the cover.
A U-shaped clamp 104 having resilient legs formed with ratchet teeth 160 co-operates with the cross-piece 120 to clamp an electrical cable 151 in the connector 2. The legs enter the apertures 121 and the teeth 160 engage the sides of the apertures 121. Wires 152 extend from the cable 151 and are each connected to a tab receptacle 130.
The tab receptacles 130 are arranged in each housing part 109. Each contact receptacle 130 includes a connecting part 161 and a receptacle part 162 extending forwardly from the connecting part 161. The receptacle part 162 is of generally channel cross-section having two arms 163 extending from either side of a web part 164. The forward and trailing ends of the arms 163 diverge outwardly and the middle portion of each arm is parallel with the corresponding middle portion of the other arm. The open side of the channel formed by the web part 164 and the arms 163 is positioned opposite the slot 110. A locking lance 165 is formed from the web part 164 of the receptacle part 162, the locking lance engaging in a pocket formed by the cover 105 and the base member 103 to prevent accidental rearward movement of the contact receptacle 130.
When the female receptacle connector 1 and the mating male connector 2 are assembled together, the housing parts 109 of the female part enter the cavities 12 of the male part 2. At the same time the contact tabs 32 enter the slot 110 and then the open side of the channel between the spaced arms 163 of the tab receptacles 130. When it is desired to disengage the connectors 1 and 2, electrical disconnection of the contacts 30 and the tab receptacles 130 will take place before the housing parts 109 are separated from the cavities 12 thereby preventing contact ofa live part of a connector after disassembly. As mentioned previously, electrical disengagement of the earth contact 30 and its corresponding contact receptacle will take place after disengagment of the remaining contacts 30 and contact receptacles 130.
Modifications can be made to connectors 1 and 2 without departing from the scope of the invention. For example, the contacts 30 are described as being inmoulded in the housing 3 of connector 1. However, they could be releasably retained in cavities in the housing by locking lances and abutment means or be a snap fit within the cavities. The connection of the wires 151, 50 to their respective connecting parts 161, 34 could be by a crimped connection or screw means.
Further, the tab receptacles 130 could be in-moulded in a moulded housing.
1. An electrical connector assembly comprising first and second releasably matable electrical connectors, each electrical connector including a housing of electrically insulating material, three cavities provided in the front mating surface of the first connector housing, said cavities being arranged at irregular spaced locations around a central axis of the first connector, three contacts of electrically conductive material in said first connector, each said contact having a contact part in the form of a tab, a major portion of one edge of each said tabs extending into one of each said cavities, said edges extending longitudinally of said cavities and being accessible for electrical contact with complementary tab receptacles only from the mating surface of the first connector housing, said tabs being arranged radially with respect to said central axis of the first connector, three housing parts provided on said second connector housing, said housing parts being complementary to said cavities and extending in the mating direction from said second connector housing, three contacts of electrically conductive material in said second connector and each having a contact part in the form of a tab receptacle, each said tab receptacle being arranged in one of said housing parts of said second connector housing, a slot in each said housing part being arranged radially with respect to the central axis of said second connector and communicating with said tab receptacles, said slots permitting access by said tab edges to said tab receptacles for establishing electrical engagement therebetween, said housing parts of said second connector being receivable in said cavities of said first connector, said tabs being located rearwardly of the front mating surface of the first connector and said tab receptacles being located rearwardly of the front mating surface of the housing parts of the second connector whereby relative movement of the first and second connectors apart causes disconnection of the electrical contacts before the separation of the housing parts from the cavities.
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