GB2102520A

GB2102520A - Cam locking coupling

Info

Publication number: GB2102520A
Application number: GB08122138A
Authority: GB
Inventors: Richard L Goodall; Richard B Goodall
Original assignee: Dixon Valve and Coupling Co LLC
Current assignee: Dixon Valve and Coupling Co LLC
Priority date: 1981-07-17
Filing date: 1981-07-17
Publication date: 1983-02-02
Also published as: GB2102520B

Abstract

A quick-disconnect cam-locking safety coupling has a hollow male plug 4 having an external peripheral groove 8. The plug 4 is received in a socket 12. The socket 12 has a pair of opposed openings 18 opposite the peripheral groove 8. A gasket 16 seals between the male plug 4 and the socket 12. A pair of cam members 22 each has a lever 34 lying adjacent the socket and a cam portion 30 passing through one of said side openings 18 and engaging the peripheral groove 8. Each cam member 22 is pivotally connected to the socket 12 for outward movement of the levers 34 away from the socket 12 to diengage the cam portions 30 from the peripheral groove 8. Each cam member 22 is locked in the groove-engaging position by a removable wire pin 40 engaged by at least one lug 36 on the socket 12 and adapted to limit the outward movement of the cam member lever 34. <IMAGE>

Description

SPECIFICATION Cam locking coupling This invention is in the field of couplings for hose and pipe, and in particularto a quick-disconnect cam locking safety coupling.

It is well known to have male and female coupling members removably locked together by a peripheral groove in one member and a pair of pivoted cam members on the other member adapted to engage the peripheral groove. The desirability of holding the cam members in the locking position is recognised by the prior art. Reference may be made for example to U.S. Patent 3,976,313 in which detents are employed to hold levers on such cam members in closed position against inadvertent rotation. In U.S.

Patent 3,124,374 a similar structure is disclosed in which rotation of a lever on a cam member is prevented by a pin having an axis parallel to the axis of the coupling and mounted in a spring biased plunger with an axis perpendicular to the axis of the pin in such a manner that depressing the plunger clears the pin away from the cam member lever to permit its rotation. The use of a detent as in U.S.

Patent 3,976,313 is risky since a relatively small force can pop the cam member free of the detent and thus permit the unlocking of the coupling. The structure of U.S. Patent 3,124,374 is relatively expensive and may malfunction when invaded by dirt.

According to the present invention there is provided a coupling comprising a hollow male plug having an external peripheral groove, a socket for receiving the male plug and having a pair of opposed side openings opposite the peripheral groove, a gasket for sealing between the male plug and the socket, a pair of cam members each having a lever lying adjacent the socket and a cam portion passing through one of the side openings and engaging the peripheral groove and each being pivotally connected to the socket for outward movement of the levers away from the socket to disengage the cam portions from the peripheral groove, and locking means for locking each cam member in the grove engaging position including a lug on the socket and a removable wire pin engaging the lug lying substantially in a plane perpendicular to the axis of the coupling and adapted to limit the outward movement of the cam member lever.

Advantageously, the cam member lever has an opening receiving a lug integral with the socket, and a pin engages an opening in the lug and the exterior of the lever. Alternatively a pin engages the exterior of the cam member lever and engages an opening in a pair of lugs on each side of the lever. If desired, the pin engaging such a pair of lugs may pass through an opening in the cam member lever. When the pin engages the exterior of the lever, it is preferred to provide a recess in the lever to receive the pin to reduce to a minimum the distance the locking device protrudes from the body of the coupling.

Embodiments of the invention will now be described by way of example, with reference to the accompanying drawings, of which: Figure lisa side elevation of a coupling in accordance with the invention.

Figure 2 is a vertical section taken on the plane indicted bythe line 2-2 in Figure 1; Figure 3 is a top-plan view of the coupling of Figure 1; Figure 4 is a side elevation of an alternative coupling in accordance with the invention, partially broken away; Figure is a vertical section taken on the plane indicated by the line 5-5 in Figure 4, partially broken away; Figure 6 is a side elevation of an alternative coupling in accordance with the invention, partially broken away; Figure 7 is a vertical section taken on a plane indicated by the line 7-7 in Figure 6, partially broken away; and Figure 8 is an elevational view of one of the cam members of the coupling of Figure 1.

As seen in Figure 1, a preferred coupling 2 in accordance with the invention has a hollow male plug 4 having external threads 6 at one end and a peripheral locking groove 8 (Figure 2) adjacent the other end. The male plug 4 has an octagonal portion 10 for engagement by a wrench. The male plug 4 is telescoped into one end of a socket 12 which is internally threaded at its other end as indicated at 14 (Figure 2). The socket 12 has an octagonal portion 15. Agasket 16 seals between the plug 4 and the socket 12. The socket 12 has opposed side openings 18 (Figure 2) opposite the peripheral groove 8 in the plug 4. Associated with each opening 18 is a cam member 22 which is pivotally mounted on a hollow pin 24 fixed to a pair of ears 26 (Figure 1) internal with the socket 12. Each cam member 22 has a cam portion 30 in engagement with the locking groove 8 and has an integral locking lever 34.

Each lever 34 has an opening 35 (Figure 2) receiving a lug 36 integral with the socket 12. Each lug 36 has an opening 38 which receives a straight portion 42 of a wire locking pin 40. The lever 34 has a recessed portion 44 for receiving the portion 42 of the pin 40 to minimise the distance the lug 36 must protrude from the body of the socket 12. The pin 40 is clipped to the lug 36 by an arm 46 running generally parallel to portion 42 and having inwardly bent portions 50 and 52 which are adapted to engage the lug 36 to keep the wire pin centred and prevent its inadvertent removal from the lug 36. Each lever 34 has an opening 56 receiving a multi-turn wire ring 50 for manipulating lever 34.

To assemble the coupling, with the cam members 22 in the elevated position as shown in phantom in Figure 2 the male plug 4 is inserted into the socket 12. When the plug 4 is seated on the gasket 16, the cam member levers 34 are rotated on the pins 24 to bring each cam portion 30 into engagement with the locking groove 8 to lock the plug 4 and the socket 12 together. On reaching the locking position, each opening 35 receives its associated lug 36. The portion 42 of the pin 40 is then inserted into opening 38 of the lug 36 to lock the lever 34 in position.

An alternative coupling socket 60 which can be substituted for the socket 12 is shown in Figure 4.

The socket 60 is essentially the same as the socket 12 with the exception that it has a modified cam member 62 mounted on the pin 24. The cam member 62 has a cam portion 64 in engagement with peripheral groove 8 of male plug 4 and an integral lever 66 having an opening 58 for the reception of a multiturn wire ring 70. As best seen in Figure 4, a pair of lugs 74,74 integral with the socket 60 lie on each side of lever 66 and each has an opening 76 in which is mounted the straight portion 78 of a wire-locking pin 80. The portion 78 of the pin 80 is received in a recessed portion 84 of lever 66.

The pin 80 has bent portions 85 and 86 on arm 88 which are adapted to engage lugs 74, 74 to centre the pin 80 and prevent its inadvertent removal. The operation of this embodiment will be obvious from the description of the operation of coupling 2.

A further alternative socket 100 in accordance with the invention is shown in Figures 6 and 7. The socket 100 is the same as the socket 60 with the exception that it employs a modified cam member 102 having a cam portion 104 in engagement with the locking groove 8 of a plug 4 and pivotally mounted on a pin 24. The cam member 102 has an integral lever 106 with an opening 108 for the reception of a multi-turn wire ring 110. The lever 106 lies between the lugs 74, 74 and has a bore 1 for the reception of the straight portion 78 of a wire-locking pin 80. The operation of this embodiment will be obvious from the description of the operation of the coupling 2.

Thus a locking device is provided in which all parts are carried by the coupling except for a removable wire pin which holds the cam lever securely. The only way the cam lever can come loose is to shear the pin. The device of the invention is simple, inexpensive and effective. The only loose part is the pin which is very cheap and can be replaced at little cost if lost.

Claims

1. A coupling comprising a hollow male plug having an external peripheral groove, a socket for receiving the male plug and having a pair of opposed side openings opposite the peripheral groove, a gasket for sealing between the male plug and the socket, a pair of cam members each having a lever lying adjacent the socket and a cam portion passing through one of the side openings and engaging the peripheral groove and each being pivotally connected to the socket for outward movement of the levers away from the socket to disengage the cam portions from the peripheral groove, and locking means for locking each cam member in the groove engaging position including a lug on the socket and a removable wire pin engaging the lug lying substantially in a plane perpendicular to the axis of the coupling and adapted to limit the outward movement of the cam member lever.

2. A coupling in accordance with claim 1 in which the lug has an opening and the pin is a clip pin which is clipped to the lug through the opening.

3. A coupling in accordance with claim 2 in which the pin engages the exterior of the cam member lever and the cam member lever has a recess accommodating the pin.

4. A coupling according to claim 1 in which each lever has an opening, and in which the lugs are adjacent their respective cam member levers and extending through the opening in the lever, the exterior of each of the levers having a recessed portion adjacent the opening in the lever, each lug has an opening therethrough lying substantially in a plane perpendicular to the axis of the coupling and the wire pin passes through each lug opening and is accommodated in the recessed portion of the adjacent lever to hold the adjacent cam member in the groove engaging position.

5. A coupling in accordance with claim 1 in which a lug is provided on the socket on each side of each cam member lever, each lug having an opening, the removable wire pin passing through the lug openings and engaging the exterior of the cam member lever to limit the outward movement of said lever, the cam member lever having a recess to accommodate the removable wire.

6. A coupling in accordance with claim 1 in which each lever has an opening and the locking means includes a pair of lugs on the socket on each side of each cam member lever, each lug having an opening, the removable wire pin passing through the lug openings in each pair of lugs and through the opening in the adjacent cam member lever to limit the outward movement of the lever.

7. A coupling in accordance with any of claims 1 to 6 in which the lugs are integral with the socket.

8. A coupling substantially as hereinbefore described with reference to Figure 1 to 3 and 8 of the accompanying drawings.

9. A coupling substantially as hereinbefore described with reference to Figures 4 and 5 of the accompanying drawings.

10. A coupling substantially as hereinbefore described with reference to Figures 6 and 7 of the accompanying drawings.