GB2195967A

GB2195967A - A coupling

Info

Publication number: GB2195967A
Application number: GB08620565A
Authority: GB
Inventors: Robert Anthony Clay
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-08-23
Filing date: 1986-08-23
Publication date: 1988-04-20
Also published as: GB8620565D0

Abstract

A coupling comprising a male member (1) having a shaft (6) provided along its length with a plurality of projections (7) of different height, width, spacing, and a female member (2) having a bore (8) provided along its length with a plurality of spaced recesses (9) of different depth and width, the recesses (9) and the projections (7) being so arranged as to provide matching recess projection pairs when the shaft (6) is received within the bore (8). A ball and socket is illustrated. The towed vehicle having the ball 3 in its cup cannot therefore be towed away by another vehicle. <IMAGE>

Description

SPECIFICATION A coupling The present invention relates to a coupling and particularly to a coupling for use in connecting a powered vehicle such as a car to a trailer vehicle such as a caravan.

According to the present invention there is provided a coupling comprising a male member having a shaft provided along its length with a plurality of projections of different height, width, spacing, and a female member having a bore provided along its length with a plurality of spaced recesses of different depth and width the bores and the projection being so arranged as to provided matching boreprojection pairs when the shaft is received within the bore.

The projections may extend from opposite sides of the shaft and the bore may be transversely elongate to enable the projections to be inserted in the bore and on relative rotation between the male and female member for the projections to be received in the recesses.

Each projection may have a height and width which correspond with the depth and width of the recesses.

The coupling may comprise five recesses and five projections.

The present invention will now be more particularly described with reference to the accompanying drawings in which: Figure 1 shows a vertical section of a coupling according to the present invention; Figure 2 shows a section taken along line A-A of Fig. 1 and including a connecting member not shown in Fig. 1, and Figure 3 shows a plan view of a female member of the coupling shown in Figs. 1 and 2 and including a locking pin not shown in those Figures.

Referring to the drawings, a coupling comprises a male member 1 and a female member 2. The male member 1 has a ball 3 dimensioned to be received in a socket 4 (Fig. 2) of a connecting member 5 mounted to the front of a caravan (not shown). Extending from the ball 3 is a shaft 6 provided with a plurality of spaced projections 7 extending from opposite sides of the shaft 6. The base of the male member 1 is also provided with an annular projection 6a.

The female member has an elongate bore 8 provided with a plurality of spaced annular recesses 9. As can be seen from Fig. 3, the bore 8 in the female member comprises a central hole 10, and a lateral hole 11 at each side and merging with the central 10. The two lateral holes 11 so interrupt the recesses 9 that the maximum width of the bore 8 coincides with the diameter of the deepest recess 9.

In order to couple the male member 1 with the female member 2 the male member 1 is so disposed that its projections 7 are aligned with the two holes 11 of the bore 8 in the female member. The member 1 is then inserted into the female member 2 until the projections 7 of the shaft of the male member 1 engage the hole 11 of the bore 8 of the female member 2 as shown in Fig. 1 and the annular projection 6a of the shaft 7 is received in an annular recess 10. The male member 1 is then rotated through 90 by means of lever 12 so that the projections 7 enter the recesses 9 and are disposed at right angles to the holes 11. This poition is shown in Fig. 2. In order to fix the male member 1 in this position a pin 13 is passed through a transverse bore 14 in female member 2 and a bore 14 in the shaft of the male member 1.

The coupling is separated by removing the pin 13, rotating the shaft of the male member 1 through 90" and withdrawing the shaft from the bore 8.

Since each opposite pair of projections 7 have a unique height and width which corresponds with only one of the recesses 9 and the spacing between adjacent pairs of projections 7 equals that between corresponding adjacent recesses 9 the male member 1 is matched to the female member. By manufacturing the male and female members in matching pairs a particular male member 1 can only be used with a particular female member 2 and cannot be removed and used with a different female member 2.

Therefore if a caravan provided with a male member 1 is separated from a car provided with a female member 2 that caravan cannot be readily connected to a different car.

1. A couplng comprising a male member having a shaft provided along its length with a plurality of projections of different height, width, spacing, and a female member having a bore provided along its length with a plurality of spaced recesses of different depth and width, the recesses and the projections being so arranged as to provide matching recess projection pairs when the shaft is received within the bore.

2. A coupling according to claim 1, wherein the projection extend from opposite sides of the shaft and the bore is transversely elongate to enable the projections to be inserted in the bore and on relative rotation between the male and female member for the projections to be received in the recesses.

3. A coupling according to claim 2, wherein the recesses are at right angles to the transverse elongate bore such that in use the male and female members are rotated through 90" relative to each other to engage the projection within the recesses.

4. A coupling according to claims 1, 2 or 3, wherein each projection has a height and width which corresponds with the depth and

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A coupling The present invention relates to a coupling and particularly to a coupling for use in connecting a powered vehicle such as a car to a trailer vehicle such as a caravan. According to the present invention there is provided a coupling comprising a male member having a shaft provided along its length with a plurality of projections of different height, width, spacing, and a female member having a bore provided along its length with a plurality of spaced recesses of different depth and width the bores and the projection being so arranged as to provided matching boreprojection pairs when the shaft is received within the bore. The projections may extend from opposite sides of the shaft and the bore may be transversely elongate to enable the projections to be inserted in the bore and on relative rotation between the male and female member for the projections to be received in the recesses. Each projection may have a height and width which correspond with the depth and width of the recesses. The coupling may comprise five recesses and five projections. The present invention will now be more particularly described with reference to the accompanying drawings in which: Figure 1 shows a vertical section of a coupling according to the present invention; Figure 2 shows a section taken along line A-A of Fig. 1 and including a connecting member not shown in Fig. 1, and Figure 3 shows a plan view of a female member of the coupling shown in Figs. 1 and 2 and including a locking pin not shown in those Figures. Referring to the drawings, a coupling comprises a male member 1 and a female member 2. The male member 1 has a ball 3 dimensioned to be received in a socket 4 (Fig. 2) of a connecting member 5 mounted to the front of a caravan (not shown). Extending from the ball 3 is a shaft 6 provided with a plurality of spaced projections 7 extending from opposite sides of the shaft 6. The base of the male member 1 is also provided with an annular projection 6a. The female member has an elongate bore 8 provided with a plurality of spaced annular recesses 9. As can be seen from Fig. 3, the bore 8 in the female member comprises a central hole 10, and a lateral hole 11 at each side and merging with the central 10. The two lateral holes 11 so interrupt the recesses 9 that the maximum width of the bore 8 coincides with the diameter of the deepest recess 9. In order to couple the male member 1 with the female member 2 the male member 1 is so disposed that its projections 7 are aligned with the two holes 11 of the bore 8 in the female member. The member 1 is then inserted into the female member 2 until the projections 7 of the shaft of the male member 1 engage the hole 11 of the bore 8 of the female member 2 as shown in Fig. 1 and the annular projection 6a of the shaft 7 is received in an annular recess 10. The male member 1 is then rotated through 90 by means of lever 12 so that the projections 7 enter the recesses 9 and are disposed at right angles to the holes 11. This poition is shown in Fig. 2. In order to fix the male member 1 in this position a pin 13 is passed through a transverse bore 14 in female member 2 and a bore 14 in the shaft of the male member 1. The coupling is separated by removing the pin 13, rotating the shaft of the male member 1 through 90" and withdrawing the shaft from the bore 8. Since each opposite pair of projections 7 have a unique height and width which corresponds with only one of the recesses 9 and the spacing between adjacent pairs of projections 7 equals that between corresponding adjacent recesses 9 the male member 1 is matched to the female member. By manufacturing the male and female members in matching pairs a particular male member 1 can only be used with a particular female member 2 and cannot be removed and used with a different female member 2. Therefore if a caravan provided with a male member 1 is separated from a car provided with a female member 2 that caravan cannot be readily connected to a different car. CLAIMS

4. A coupling according to claims 1, 2 or 3, wherein each projection has a height and width which corresponds with the depth and width of the recesses.

5. A coupling according to any preceding claim, wherein the coupling comprises five recesses and five projections.

6. A coupling according to any preceding claim, wherein a transverse bore is provided through both the female member and the shaft, which two bores are aligned when the projection are received within the recesses, and a locking pin is releasably received within the transverse bore to lock the male and female members together.

7. A coupling substantially as hereinbefore described with reference to the accompanying drawings.