GB2076495A - Clevis joint - Google Patents

Abstract

In a clevis joint including a bifurcated clevis (1) having arms (2) and (3), a blade spring (16) is provided on the inside of the arm (2) to prevent rattle of a component (6) received between the arms (2) and (3) and coupled to the clevis (1) by a pin (10). <IMAGE>

Description

SPECIFICATION Clevis joints This invention relates to clevis joints. Such joints are used to couple two components, such as rods and/or cables, and are used in mechanical assemblies, for example in vehicles, to couple levers and power transmission rods and/or cables of braking or other control systems.

Clevis joints of this kind and referred to hereafter as joints of the kind set forth include a bifurcated clevis, one end of which is adapted for connection to an end of the first component, and at the other end is adapted to carry an apertured or eyed end of the second component between the arms of the clevis, by means of a headed pin passed through aligned holes in the arms and the aperture of the second component, with the head of the pin in abutment with the outer side of one arm, and the tail of the pin projecting through to the outer side of the other arm, the pin being retained by a split pin passing through a transverse hole in the projecting tail of the pin.

In one known clevis joint of the kind set forth, the head of the pin is screw-threaded, and is adapted to screw into an enlarged hole in one arm.

A coil spring is provided round the pin, and is compressed between the head of the pin and the second component, to bias that component against the other arm to prevent rattling in use.

One disadvantage of this construction is that the arm may be weakened by the enlarged hole, and that the pin and its connection to the clevis has to be sufficiently strong to transmit the load of the spring to the clevis. A further disadvantage is that due to the provision of the spring the second component is substantially offset, and this may enhance any weaknesses during use. Further, the pin in this construction is designed specially, and so is not only costly to manufacture, but also may be difficult to replace in an emergency.

According to our invention, in a clevis joint of the kind set forth resilient means for preventing rattle of the second component act directly between one arm of the clevis and the second component.

The resilient means is preferably mounted on the arm of the clevis itself.

This enables the construction to be simplified, as the loading of the resilient means is taken by the clevis and is not transmitted through the pin.

Preferably the pin is plain, and the holes in the arms are of substantially equal sizes.

The means that the pin is easier to replace, or to improvise, for in an emergency, and is more economical to manufacture.

The resilient means preferably comprises a blade spring conveniently attached to one arm of the clevis. The blade spring may have cranked side lugs which fit round the arm, and enable the spring to be assembled or removed by sliding it on or off the arm.

The blade spring can be accommodated in a relatively small space, sufficient to accommodate the thickness of the blade spring, which is substantially less than that required to accommodate a coil spring. The spacing between the arms can be relatively reduced and, in consequence, the arms can be made thicker and stronger without increasing the overall dimensions of the clevis joint. This also has the advantage thaf the second component is less offset.

The clevis joint may also, if required, provide a simple method of ensuring that the pin does not rotate by providing a flat on the head, which engages with a flat on a complementary projection on the outer side of the arm adjacent to the head.

Thus the invention provides a simpler and more effective clevis joint which is also more economical to manufacture.

One embodiment of the invention is illustrated in the accompanying drawings, in which Figure 1 is a plan view of a clevis joint in accordance with the invention; Figure 2 is a section along the line 2-2 in Figure 1; and Figure 3 is a side view of part of the clevis joint showing a modification.

The clevis joint shown in the drawings comprises a bifurcated clevis 1 having arms 2 and 3. At one end of the clevis 1 is provided a tapped hole 4 which provides the connection for the first component which comprises a rod 5. At the other end the clevis is adapted to carry the second component, which comprises a force transmitting member 6, suitably a lever or cable, between the arms 2 and 3. The member 6 is provided for this purpose with an eyed end 7. The arms 2 and 3 have aligned plain holes 8 and 9 respectively, formed adjacent their ends. A cold-headed plain cylindrical pin 10 is adapted to pass through the holes 8 and 9 and the eyed end 7 of the member 6. The head 11 of the pin 1 0 abuts the outer side of the arm 2. The other, tail end 12 of the pin 10 projects through the hole 9 to the outer side of the arm 3.The projecting tail end 1 2 is provided with a transverse hole 1 4 through which a split pin 1 5 is passed to retain the pin 10 in position.

The resilient means for preventing the member 6 from rattling during use comprises a blade spring 1 6 provided on the inside of the arm 2. The blade spring 1 6 is provided at one end with edge portions 1 7 which are bent to form upstanding lugs 1 8 having inwardly directed cranked ends 1 9 so that the edge portions are able to receive the arm 2. The spring 16 can be slid onto the arm 2, and when in position the lugs 18 are located adjacent to the connection 4, to serve detachably to secure the spring 1 6 to the arm 2. The other end of the spring 1 6 is located adjacent to the inside cf the arm 2, and is bifurcated to receive the pin 10.The portion 20 of the spring adjacent the pin 10 is shaped by permanent deformation so that it can bias the member 6 against the arm 3, and the extreme ends of the spring 1 6 are shaped to facilitate assembly of the joint.

The assembly of the joint is effected as follows.

The rod 5 is screwed into the tapped hole 4, either before or after the blade spring 1 6 has been slid onto the arm 2 of the clevis 1. The eyed end 7 of the member 6 is then inserted between the arms and aligned with the holes 8 and 9, causing the spring 1 5 to deflect and bias the end 7 into place against the arm 3. The pin 10 is then inserted through the hole 8, the end 7 and the hole 9. To complete the assembly the split pin 1 5 is then passed through the hole 14.

In a modification (not shown), a washer can be provided on the projecting tail end 12 of the pin 10 between the arm 3 and the split pin 1 5. The washer is assembled after the pin 10 has been inserted and before the split pin 1 5 is fitted.

In further modifications the clevis joint can be used with a cable having a threaded sleeve for engagement with the hole 4, instead of the rod 5, and the member 6 may comprise an arm or rod formed with an eyed end.

In the modification shown in Figure 3, means are provided for preventing the pin from rotating in use.

These means comprise a flat 20 formed on the pin head 11, which engages with a substantially parallel flat 22 formed on a pad 23. The pad 23 is secured to the outer side of the arm 2 adjacent the head 11 by any suitable means. The engagement of the surfaces 21 and 22 prevent the pin from rotating.

Claims (7)

1. A clevis joint of the kind set forth in which resilient means for preventing rattle of the second component act directly between one arm of the clevis and the second component.

2. A clevis joint as claimed in Claim 1, in which the resilient means is mounted on the arm of the clevis itself.

3. A clevis joint as claimed in Claim 1 or Claim 2, in which the pin is plain, and the holes in the arms are of substantially equal sizes.

4. A clevis joint as claimed in any preceding claim in which the resilient means comprises a blade spring attached to one arm of the clevis.

5. A clevis joint as claimed in Claim 4, in which the blade spring has cranked side lugs which fit round the arm, and enable the spring to be assembled or removed by sliding it on or off the arm.

6. A clevis joint as claimed in any preceding claim, in which a fiat provided on the head of the pin engages with a flat on a complementary projection on the outer side of the arm adjacent to the head.

7. A clevis joint substantially as claimed herein with reference to and as illustrated in the accompanying drawing.