GB2296060A

GB2296060A - Quick fitting nut

Info

Publication number: GB2296060A
Application number: GB9425281A
Authority: GB
Inventors: Geraint Wyn Owen; Steven John Culley; Antony Roy Mileham
Original assignee: University of Bath
Current assignee: University of Bath
Priority date: 1994-12-13
Filing date: 1994-12-13
Publication date: 1996-06-19
Also published as: GB9425281D0

Abstract

A screw threaded nut (1) comprises two interconnected halves (1A, 1B) moveable with respect to each other from an open position (figure 1) to a closed position (figure 2). In the open condition a screw threaded member (8) can be moved inside the nut (1) without turning. In figure 1, the sliding nut halves (1A, 1B) are closed by the action of a cam (6) on half 1B. In figure 7, the pivoted nut halves (1A, 1B) are closed by engaging the end (15) of a lever (14) in a recess in the half 1B. Further possible improvements include a detachable handle (7) and a means for locking the nut (1) and the cam (6) in the closed position. <IMAGE>

Description

OUICK FITTING NUTS This invention relates to nuts that can be quickly positioned and tightened, and after release can be quickly removed.

Nuts, used in conjunction with either screw threaded studs or bolts, are extensively used in many different situations and products for clamping, locating and adjustment. Generally, nuts are of a hexagonal form and are tightened through several turns using a spanner or other similar wrench. In situations where quick fitting, removal or adjustment are required, the need to use a spanner and the number of turns required to move the nut represent an inconvenience. Further problems can also be experienced when trying to move a nut across a portion of damaged thread, or starting a nut on the end of a damaged thread.

Some so-called lock nuts are configured to have a selflocking effect when tightened. A particular form of lock nut is a threaded collar split axially into two halves and having outwardly directed opposed flanges at each side of the split. A bolt passed through aligned holes in the flanges carries a nut. With this bolt and nut released, the collar can be engaged onto a screw thread, rotated to run down the thread and tightened in its desired final position. Once fully tightened, the collar can be locked in position by tightening the bolt and nut.

The collar is always in substantially full engagement with the thread to which it is fitted, tightening or releasing of the bolt and nut only having the effect of either locking the collar in position, or releasing it for running along the thread. Thus the collar has to be fitted to the thread, and rotated to move along the thread, with attendant problems if the thread is damaged at its end, and has to be rotated to run all the way along the thread to the desired final location, with further problems if the thread is damaged anywhere along its length.

According to one aspect of the present invention there is provided a screw threaded nut comprising two interconnected body halves movable with respect to one anther from a nut open condition in which a screw threaded member can be located between the body halves and there can be relative movement in the longitudinal axial direction of the screw threaded member between the nut and the screw threaded member without rotation of either the nut or the screw threaded member, and a nut closed condition in which the nut is screw-threadedly engaged with the screw threaded member so that the nut and the screw threaded member can be made fast with one another by relative tightening rotation.

According to another aspect of the present invention there is provided a screw threaded nut comprising two interconnected body halves movable with respect to one another from a nut open condition in which the nut can be placed around a screw threaded member close to its desired location on this member, and a nut closed condition in which the nut is screw threadedly engaged with the screw threaded member so that the nut and the screw threaded member can be made fast with one another with the nut at said desired location by relative tightening rotation.

In opened condition either of the nuts just defined can be fitted to a screw threaded member, after relative axial movement or not as the case may be, close to its desired final location, or a screw threaded member can be so located in the nut, and with the nut closed around the thread tightening can be effected without significant relative axial movement of the nut and the screw threaded member. In addition to this quick positioning of the nut, or the member in the nut, damage to the thread at its end or along its length is not a problem as the nut does not have to negotiate this damage whilst in screw threaded engagement with the member.

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a perspective view of a quick fitting nut in opened condition; Figure 2 is a perspective view of the nut of Figure 1, shown in closed condition; Figure 3 is a perspective view of part of the nut of Figures 1 and 2, illustrating removal of a handle thereof; Figure 4 is a perspective view of another form of quick fitting nut, shown in opened condition; Figure 5 is a perspective view of the nut of Figure 4, shown in closed condition; Figure 6 is a perspective view of a further form of quick fitting nut, shown in opened condition; and Figure 7 is a perspective view of the nut of Figure 6, shown in closed condition.

Referring first to Figures 1 and 2, the nut 1 is in two interconnected halves 1A , 1B so that the nut is split in two axially. The body half 1A has two arms 2 on which the body half 1B is mounted for sliding towards and away from the body half 1A. The two halves 1A, 1B are urged apart by springs 3.

Outboard of the body half 1B the arms 2 have pivoted to them, at 4, a cam lever 5 having a cam profile 6 that acts on the body half 1B, and an operating handle 7.

In the opened condition of the nut 1 (Figure 1) it can be placed on a screw thread 8 with the body halves 1A, 1B, well clear of the screw thread so that the nut can be moved axially along the thread into close to its final location without any rotational movement and hence passing freely over any damage that there may be to the thread.

Having thus quickly located the nut 1 where desired, the handle 7 is swung so that the cam profile 6 acts on the nut body half 1B to close the nut around the screw thread 8, the body half 1B moving against the action of the spring 3 perpendicularly to the axis of the thread 8. In its closed condition the nut 1 is in full screw threaded engagement with the thread 8 and can be fully tightened, conveniently by using the handle 7 of the cam lever 5 as a tommy bar.

The cam profile 6 is such that the cam lever 5 goes overcentre into the nut closed condition and so tends to remain in this position until released. However, there can be provision, indicated in dotted lines at 9 in Figure 2, for passing a pin or spring clip through the arms 2 and the cam lever 5 positively to retain the cam lever in its nut closed position.

Quick release of the nut 1 is achieved by first unscrewing the nut to release the tension imposed when effecting the full tightening described above, and by then swinging the cam lever 5 to its nut open position so that the springs 3 can assert themselves to move the body halves 1A, 1B apart. The nut 1 is thus freed for axial movement without rotation back along the screw thread 8.

The cam lever handle 7 can be a removable fit in the cam profile bearing part of the cam lever 5 so that the handle 7 can be removed after the nut 1 has been closed, as illustrated in Figure 3, if it would otherwise constitute an obstruction. If removal is necessary before the handle 7 can be used as a tommy bar fully to tighten the nut 1 as described above, the full tightening of the nut 1 can be effected using a spanner or wrench.

In the form of Figures 4 and 5 the nut 1 is for mounting on a surface for receiving a bolt. To this end, the body half 1A has one arm 2 as described above but this arm 2 opposes a mounting plate 10 which the body half 1A is fast with and which has slots 11 for screws (not shown) to retain the plate 10 on a surface. The body half 1B is mounted between the arm 2 and the plate 10 for sliding towards and away from the body half 1A, the two halves 1A, 1B being urged apart by the springs 3. The cam lever 5 is also mounted between the arm 2 and the plate 10 for pivoting about the pivot at 4.

Operation is substantially as described above, save that in this form the cam lever 5 pivots about an axis that is parallel with a bolt (not shown) engaged in the nut, whereas in the form of Figures 1 and 2 the pivot axis of the cam lever 5 is transverse of the axis of the screw thread 8. Furthermore, in this form final tightening is achieved by turning the bolt engaged in the nut 1.

In the form of Figure 6 and 7 the two body halves 1A, 1B are pivotally interconnected for pivoting, about a pivot 12, from a nut fully open position in which the nut can be placed around a screw thread (not shown) on which the nut 1 is to be tightened, close to the desired final location of the nut. The axis of the pivot 12 is parallel to that of the screw thread on which the nut 1 is to be tightened.

The nut body half 1A has pivoted to it two arms 13 that in turn pivotally carry a cam lever 14, the cam profile 15 of which can engage in a hook profile 16 carried by the nut body half 1B.

In use the fully open nut 1 is placed around a screw thread close to its desired final location. The nut 1 is then closed sufficiently far to enable the cam profile 15 to be engaged in the hook profile 16, whereafter the nut 1 is fully closed around the screw thread by pivoting the cam lever 14 into an over-centre position, the cam action between the profiles 15 and 16 serving fully to close the nut 1, which can then be tightened. The nut 1 can subsequently be released by pivoting the cam lever to disengage the cam profile 15 from the hook profile 16, after first unscrewing the nut sufficiently to release the tension imposed when fully tightening it.

In all forms the cam lever handle can be removable, if desired, in the manner described with reference to Figure 3.

Also in all forms it is possible to arrange the camming action such that in an initial closed position the nut 1 can be tightened, whereafter the cam lever is moved into a final closed position to lock the nut 1 in position.

Claims

1. A screw threaded nut comprising two interconnected body halves movable with respect to one another from a nut open condition in which a screw threaded member can be located between the body halves and there can be relative movement in the longitudinal axial direction of the screw threaded member between the nut and the screw threaded member without rotation of either the nut or the screw threaded member, and a nut closed condition in which the nut is screw threadedly engaged with the screw threaded member so that the nut and the screw threaded member can be made fast with one another by relative tightening rotation.

2. A screw threaded nut comprising two interconnected body halves movable with respect to one another from a nut open condition in which the nut can be placed around a screw threaded member close to its desired location on this member, and a nut closed condition in which the nut is screw threadedly engaged with the screw threaded member so that the nut and the screw threaded member can be made fast with one another with the nut at said desired location by relative tightening rotation.

3. A screw threaded nut as claimed in claim 1 or 2 and comprising camming means for moving one body half with respect to the other body half to place the nut in said nut closed condition.

4. A screw threaded nut as claimed in claim 3, wherein the camming means can act on the nut, in the nut closed condition, to lock the nut in this condition.

5. A screw threaded nut as claimed in claim 3 or 4, wherein the camming means includes a cam lever pivotally mounted on said other body half for action on said one body half.

6. A screw threaded nut as claimed in claim 5, wherein the camming means further includes a removable operating handle for the cam lever.

7. A screw threaded nut as claimed in claim 5 or 6, wherein the camming means further includes means for locking the cam lever when the nut is in its closed condition.

8. A screw threaded nut as claimed in any one of claims 1 to 7, wherein said one body half is slidably supported by said other body half for movement into and out of said nut closed condition.

9. A screw threaded nut as claimed in claim 8, wherein the body halves are resiliently biased into said nut open condition.

10. A screw threaded nut as claimed in any one of claims 1 to 7, wherein said body halves are pivotally interconnected.

11. A screw threaded nut substantially as hereinbefore described with reference to Figures 1 and 2, or Figures 4 and 5, or Figures 6 and 7, or with or without Figure 3, of the accompanying drawings.