GB1597164A - Electrical connector - Google Patents

Description

(54) AN ELECTRICAL CONNECTOR (71) We, Ross COURTNEY & COMPANY LIMITED, a company registered under the laws of Great Britain, of Terminal House, Elthorne Road, London N19, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed to be particularly described in and by the following state ment:- This invention relates to an electrical connector. More especially, the invention relates to an electrical connector for releasably connecting a pair of leads.

Such connectors are known to comprise a blade or tab connectable to a first lead and engageable with a receptacle usually crimped to the second lead. Usually the first lead is part of an electronic or domestic appliance and the blade or tab forms part of that appliance. Usually the connector formed by the combination of blade and receptacle is insulated and protected by a casing known as a boot. Various mechanisms have been proposed for securing the blade and receptacle together in a manner which ensures that the electrical path between the first and second leads is not interrupted simply by a tug or pull on one or both leads. At the same time, the facility is required that the leads are releasably connected.

In the past the receptacle has been provided with an upstanding strap adapted to interlock with the blade. One means of adapting the strap has been to provide the strap with an upstanding projection engageable with an aperture in the blade. It is well known in the art that the receptacle has Ushaped configuration the sides of which are inwardly and downwardly inclined to provide a recess into which the blade may be inserted whilst slidingly guided on its upper, lower and side surfaces. Usually the blade is a plateshaped member of rectangular section at its leading end. Laterally extending abutments may limit the insertion of the leading end in the receptacle and the tail portion which remains projecting out of the receptacle is adapted for connection to its lead, possibly by having a central aperture. An intermediate portion between the leading end and the tail portion may be of reduced lateral dimension.

The upstanding strap of the receptacle may have been formed by stamping it out of a lower web surface of the U-shaped receptacle or a folded back tail of the U-shaped receptacle.

According to one recent proposal an electrical connector has been provided with a blade engageable with a folded back strap having an upstanding end portion which extends above the receptacle for depression thereby to release a projection on the strap from engagement with an aperture in the blade, the depression being accomplished by sliding movement of a moulded boot encasing the blade and receptacle such that a downwardly inclined surface of the upper wall of the boot displaces said upstanding end portion downwardly relative to the strap to disengage the projection upstanding from the blade, the latter slidingly entering the receptacle above the strap.

Boots for such receptacles and the prior known receptacles have been adapted for limited motion relative to the receptacle. It has not been intended that the boot should be capable of accidental displacment. Usually therefore the boot, generally open ended and rectangular in lateral cross-section, is provided with laterally extending abutments to prevent or limit longitudinal displacement of the boot. In addition, some prior boot configurations have included a central web or flange depending from the lateral mid-point of a top inner surface of the boot for orientating the boot with respect to the receptacle so that the upper surface of the boot overlies the blade receiving recess.

As indicated above some of these connectors are for heavy current applications such domestic appliances for which a boot is designed to receive a blade width of 0.25 inches. Other connectors are for electronic applications for which a boot is designed to receive a blade width of 0.110 inches.

The production of boots for heavy current applications may be by moulding, the interior configuration being determined by core inserts which are inserted from both ends to meet intermediate the length of the boot. For boots to be used in electronic applications, this forming of moulding is not practicable as the scale of the dimensions does not permit the use of core inserts.

The present invention seeks to provide a boot for a blade and receptacle connector of a design which enables manufacture for both electronic and heavy current appliances, the boot having a strap release surface.

Accordingly, the present invention provides a boot for a blade-receptacle electrical connector comprising a longitudinal housing having an upper wall, a first opening at one end for receiving a receptacle connector part and a second opening at its respective other end to receive a blade connector part, an intermediate portion of the upper wall having a leading ridge, said intermediate portion being formed as an upstanding portion of said upper wall hingedly connected thereto for positioning in a closed position to engage the remainder of the upper wall to close an aperture in the upper wall as formed with said intermediate portion upstanding and provide a strap release surface.

In the preferred embodiment the internal contour of said upper wall of the housing has a spacing relative to the internal contour of a lower wall of the housing which over said intermediate portion reduces progressively in a direction between said first opening to said second opening. The intermediate portion may interlockingly engage an edge of the aperture. The leading ridge may engage in said interlocking engagement with a recess in said edge of the aperture.

There is further provided an electrical connector receptacle with a strap adapted for use with the boot defined above.

The present invention further provides an electrical connector receptacle in combination with a boot as defined above having a Ushaped body configuration the sides of which are inwardly and downwardly inclined to provide a recess into which a connector blade may be inserted whilst slidingly guided on its upper, lower and side surfaces, and upstanding strap formed by being stamped out of the web of the U-shaped body, the strap having an upwardly directed projection for engagement with a connector blade and an upstanding portion arranged for depression by a strap release surface on a suitably adapted electrical connector boot to release said upwardly directed projection, said strap resiliently urging said upwardly directed projection oppositely to the direction of depression by the upstanding portion. The receptacle above defined may be formed from sheet metal more readily than receptacles with folded back strap portions and with a simple stamping operation. The receptacle is severed from its blank at the junction with the forward edge of its U-shaped parts. The metal wastage may be minimised. As with prior receptacles, the U-shaped body comprises the blade receiving part and is attached to a trailing part adapted to be crimped to an electric lead. With this combination of receptacle and boot, it is not necessary for the strap to extend above the receptacle, i.e.

above the sides, nor is it necessary that the strap extends rearwardly of the sides. In a preferred embodiment, the ridge may have a depending portion which depends between the inwardly and downwardly inclined sides to be engageable with the upwardly directed projections of the strap.

By way of an alternative embodiment, the strap may be integral with the blade.

Embodiments of the invention will now be described by way of example only, with reference to the accompanying drawings in which: Fig. 1 shows a perspective view of a boot and receptacle of an electrical connector; Figs. 2 to 7 relate to the boot of Fig. 1 and show a side elevation, one opening end elevation, plan, section taken on line B B, the other end elevation, and a fragmentary side elevation of a hinged intermediate portion, respectively; and, Figs. 8 to 15 relate to the receptacle of Fig.

1 and show a plan of the stamped blank, section on line X-X, section on line Y-Y, section on line ZZ, a plan of the shaped blank, a side elevation of the shaped blank, a section on line S-S and a plan view R on the Section S-S.

In Fig. 1 the perspective view of the boot 10 and receptacle 20 of an electrical connector for releasably connecting a pair of leads both are mutually aligned for insertion of the receptacle 20.

As seen in Figs. 1 to 7, the boot 10 comprises a boot housing having a first opening 11 (Fig. 6) at one longitudinal end for receiving a receptacle connector part 20 (Fig. 1) and a second opening 12 (Fig. 3) at its respective other longitudinal end to receive a blade connector part (not shown). The internal contour of an upper wall 14 of the housing has a spacing relative to the internal contour of a lower wall 15 of the housing which spacing varies longitudinally of the housing between the first opening 11 to the second opening 12. As shown in Fig. 7 the spacing variation occurs only over an intermediate portion16 longitudinally of said upper wall 14. This intermediate portion 16 depends downwardly and is inclined in the direction X (Fig. 1) from the first opening 11 to the second opening 12. The intermediate portion 16 is formed with an upstanding portion 17 hingedly connected to upper wall 14 for positioning in a closed position to engage the remainder of the -upper-wall 14 to close an aperture 18 in the upper wall 14, as formed with the upstanding portion 17 and provide a strap release surface 19. The upstanding portion 17 is hingedly connected to that portion 41 of the upper wall 14 which extends to said first opening 11 (Fig. 4) and when positioned to close said aperture 18 is turned downwardly to interlockingly engage by means of a leading ridge 71 (Fig. 7) on its forward edge 72 that por tion 42 of the upper wall which extends to the second opening 12.

As the fragmentary side elevation of Fig. 7 illustrates the leading edge 72 which has leading ridge 71 for engagement with the underside of upper wall portion 42, also in corporates a recess 73 into which the trailing edge 43 of upper wall portion 42 is placed when upstanding portion 17 is placed in its closed position, closing aperture 18. In the closed position, the upstanding portion 17 becomes a downwardly and forwardly in clined intermediate portion 16 in which attitude the ridge 71 may function as a strap release member. Upstanding portion 17 is hingedly connected to upper wall portion 41 by a hinge portion 44 of such reduced thick ness relative to portions 17 and 41 as to readily allow the portion 17 to be pushed forward by light finger pressure into the closed position.

Optionally, guidance of the portion 17 into this position is assisted by side flanges 74 shown in Figs. 3 and 5.

The boot 10 is moulded from plastics material having sufficient resilience to allow the edges 43 and 71 to deflect on closing so that the edge 71 snaps into position behind the edge 43. Such a material is available as NYLON or POLYPROPYLENE.

On insertion of the blade (not shown), lateral abutments on the blade limit the inser tion of the blade by abutment in recesses 32 in side walls 33 of the boot 10.

After insertion the receptacle 20 is held in the boot 10 by means of leading edge 34 at the opening 12 and ridge 171 on portion 17 as will be described below.

Turning to Figs. 1 and 8 to 15, the recep tacle 20 for insertion in boot 10 is fabricated by stamping from conductive sheeting 81 in Fig. 8. Each receptacle 20 has a U-shaped blade receiving part 82 from which upstand ing strap 83 with upwardly directed projection 84 is severed, and a trailing part 85 to be crimped to a lead 86. In Fig. 8 the part 82 has been stamped out of flat sheeting. It then has to be formed into the configuration shown in Figs. 12 and 13 with cross-sections as shown in Figs. 9, 10 and 11 to the part 82, a mid-part 87 and part 85, respectively. For positive guiding of the blade (not shown) side walls 91 upstanding from web 92 of blade receiving part 82 (Fig. 9) guide the blade side edge whereas depending turned over edges 93 guide the upper surface of the blade. Engagement of the lower surface of the blade is by strap 83.

The strap 83 shown in greater detail in Figs. 14 and 15 has an upwardly directed projection 151 and the upwardly directed projection 84. Projection 151 engages a suitable aperture in the blade for releasably interlocking with the blade. As shown in Fig.

1 side walls 91 and turned in edge 93 extend rearwardly beyond the tongue 84, but in Figs.

12 to 14 are shortened for illustrative purposes. When receptacle 20 is located in housing 10, upwardly directed projection 84 is arranged behind the leading edge 71 strap release surface 19 of the boot 10. Also, top portions 94 of blade receiving part 82, which are situated between its side walls 91 and its turned over edges 93, are located between ridge 171 and opening 12 (Fig. 1). Since leading ridge 71 has a width which allows it to project below the level of top portions 94, engagement with strap portion 84 is effected without requiring the portion 84 to extend above walls 91 or edges 93.

Thus, when boot 10 covers the assembly of receptacle 20 and a blade, receptacle 20 is limited in its longitudinal movement relative to boot 10 by surface 34 and ridge 171 of the boot 10 abutting forward and rearward edges 121, 122 (Figs. 12 and 13) of top portions 94 of blade receiving part 82.

For release of strap 83, upstanding portion 84 is depressed to disengage upwardly directed portion 151 from an aperture in the blade (not shown). Depression of upstanding portion 84 is effected by relative displacement of boot 10 and receptacle 20 to move upstanding portion 84 towards leading ridge 71 on strap release surface 19. Usually the boot 10 will be displaced towards the lead 86 (Fig. 1). Whilst this displacement is sufficient to cause disengagement of upwardly directed projection 151 and therefore release strap 83, the displacement is not sufficient to force upstanding portion 84 below the leading ridge 71 for the purpose of unlimited travel of boot 10 towards lead 86, which in any event is prevented by ridge 171.

It follows that since ridge 71 depends between edges 93 into the path of strap portion 84, that the inclined surface 19 is not essential to the release operation. The housing of Fig. 2 may be modified to include a construction in which surfaces 41, 42 and 19 are coplanar.

Modifications to the cross-section of the boot may be made whilst retaining the latch release feature of the above embodiment.

Choice in the selection of plastics or other materials for the boot depends on the requirements regarding (a) insulation and (b) elastic deformation of the leading ridge and/or the edge of the upper wall engaged thereby as well as (c) the ability of the upstanding portion to turn about the hinge between the upstanding portion, when formed, and the reanward upper wall part.

In use this boot has the features of (1) advantageous mode of manufacture, (2) positive limitation on relative displacement between boot and receptacle and (3) positive provision for quick release of a strap on the receptacle from a blade engaged thereby.

WHAT WE CLAIM IS: 1. A boot for a bladereceptacle electrical connector, comprising a longitudinal housing having an upper wall, a first opening at one end for receiving a receptacle connector part and a second opening at its respective other end to receive a blade connector part, an intermediate portion of the upper wall having a leading ridge, said intermediate portion being formed as an upstanding portion of said upper wall hingedly connected thereto for positioning in a closed position to close an aperture in the upper wall as formed with said intermediate portion upstanding and to position said ridge to provide a strap release member.

2. A boot as claimed in Claim 1, wherein the internal contour of said upper wall of the housing has a spacing relative to the internal contour of a lower wall of the housing which over said intermediate portion reduces progressively in a direction between said first opening to said second opening.

3. A boot as claimed in either Claim 1 or Claim 2, wherein said intermediate portion interlockingly engages an edge of the aperture.

4. A boot as claimed in Claim 3, wherein said leading ridge engages in said interlocking engagement with a recess in said edge of the aperture.

5. In combination a boot as claimed in any one of Claims 1 to 4, together with an electrical connector receptacle comprising a U-shaped body the sides of which are inwardly and downwardly inclined to provide a recess into which a connector blade may be inserted whilst slidingly guided on its upper, lower and side surfaces, an upstanding strap formed by being stamped out of the web of the the U-shaped body, the strap having an upwardly directed projection for engagement with a connector blade and an upstanding portion arranged for depression by the strap release member on the boot to release said upwardly directed projection, said strap resiliently urging said upwardly directed projection oppositely to the direction of depression by the upstanding portion.

6. A boot for a blade-receptacle electrical connector, arranged, constructed and adapted to operate substantially as hereinbefore described with reference to Figs. 1 to 7 of the accompanying drawings.

7. In combination a boot as claimed in Claim 6, together with an electrical connector receptacle, arranged, constructed and adapted to operate substantially as hereinbefore described with reference to Figs. 1 and 8 to 15 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. upstanding portion, when formed, and the reanward upper wall part. In use this boot has the features of (1) advantageous mode of manufacture, (2) positive limitation on relative displacement between boot and receptacle and (3) positive provision for quick release of a strap on the receptacle from a blade engaged thereby. WHAT WE CLAIM IS:

1. A boot for a bladereceptacle electrical connector, comprising a longitudinal housing having an upper wall, a first opening at one end for receiving a receptacle connector part and a second opening at its respective other end to receive a blade connector part, an intermediate portion of the upper wall having a leading ridge, said intermediate portion being formed as an upstanding portion of said upper wall hingedly connected thereto for positioning in a closed position to close an aperture in the upper wall as formed with said intermediate portion upstanding and to position said ridge to provide a strap release member.

2. A boot as claimed in Claim 1, wherein the internal contour of said upper wall of the housing has a spacing relative to the internal contour of a lower wall of the housing which over said intermediate portion reduces progressively in a direction between said first opening to said second opening.

3. A boot as claimed in either Claim 1 or Claim 2, wherein said intermediate portion interlockingly engages an edge of the aperture.

4. A boot as claimed in Claim 3, wherein said leading ridge engages in said interlocking engagement with a recess in said edge of the aperture.

5. In combination a boot as claimed in any one of Claims 1 to 4, together with an electrical connector receptacle comprising a U-shaped body the sides of which are inwardly and downwardly inclined to provide a recess into which a connector blade may be inserted whilst slidingly guided on its upper, lower and side surfaces, an upstanding strap formed by being stamped out of the web of the the U-shaped body, the strap having an upwardly directed projection for engagement with a connector blade and an upstanding portion arranged for depression by the strap release member on the boot to release said upwardly directed projection, said strap resiliently urging said upwardly directed projection oppositely to the direction of depression by the upstanding portion.

6. A boot for a blade-receptacle electrical connector, arranged, constructed and adapted to operate substantially as hereinbefore described with reference to Figs. 1 to 7 of the accompanying drawings.

7. In combination a boot as claimed in Claim 6, together with an electrical connector receptacle, arranged, constructed and adapted to operate substantially as hereinbefore described with reference to Figs. 1 and 8 to 15 of the accompanying drawings.