GB2452046A

GB2452046A - Sprung socket clamp for round objects

Info

Publication number: GB2452046A
Application number: GB0716291A
Authority: GB
Inventors: Simon Barrow Dowling
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-08-21
Filing date: 2007-08-21
Publication date: 2009-02-25
Also published as: GB0716291D0

Abstract

A clamp comprises two clamp halves 1a, 1b at least one of which is associated with a gripping means (e.g. seating 6); a clamping means (e.g. a bolt 2 with thumbwheel nut 3); and 'third means' (e.g. spring 5) to draw the clamp halves together at least at one end. Preferably the spring 5 is a double torsion spring and is seated in recesses in the clamp halves such that the two clamp halves are held apart at one end and closed at the other (figure 2). The gripping means 6 may further comprise V grooves 7, 8 such that round or spherical objects such as balls, cylinders and bars may be accommodated in clamp. The device may be used for connecting two objects, such as ball ended rod 4 or tubular items.

Description

Ball Clamp This invention is a development of an earlier invention entitled BALL JOINT / CLAMP, application number 9103277.1 filed by the present inventor on 15th Feb 1991.

The invention is a development of a double ball coupling comprising a pair of clamp halves each having a pair of seatings and having central clamping means to draw the two halves together onto the ball ends of the two rods or tubes to be coupled. This type of coupling is not novel. However, in this invention, V grooves are set across the seatings and a double torsion return spring is housed around the central clamping means, so arranged that it exerts its opening load off centre from the line of action of the clamping means, thereby tilting the clamp halves together at the end furthest from the point of application of spring load, onto a ball end or cylinder, forming a pivot thereby. Operation of the clamping means makes the ends of the clamp halves furthest from the pivot open and close under the combined influence of the spring, clamping means and pivot, to form a clamp suitable for gripping tubes of various diameters, or another ball end, or other items such as a table top or other equipment. It can therefore function either as a clamp incorporating a universal joint of adjustable stiffness co-operating with a ball ended rod or other fixture, or as a double ball joint of adjustable stiffness having a very large range of movement (the clamp halves co-operating with a pair of ball ended rods or fixtures) or as a clamp joining tubes of various diameters. Rods or tubes may be ball ended both ends (allowing for a succession of rods and joints), or one end only having another fitting (a camera or microphone mount for example) on the other end. By combining these various possibilities, a wide variety of configurations and functions may be achieved.

A preferred embodiment of the invention will now be described by way of example and with reference to the accompanying drawings.

Figure 1 is an Exploded view of the coupling, Fig 2 is a cross section through the four seating centres. Figure 3 is a view of one clamp half showing the seatings and spring housing.

With reference to Figs 1.2 and 3, two identical clamp half castings I a and lb are drawn together by a centre bolt 2 and thumbwheel nut 3 while pivoting about ball end 4 and being kept apart and correctly located in register with the ball end and the clamping means by double torsion return spring 5. Each clamp half has a pair of seatings 6 through the centres of which are formed v grooves 7 (laterally) and 8 (along the length of the clamp half). A pocket 9 is formed in the centre of each clamp half to house the double torsion spring 5, with additional positive location of the spring being provided by pads 10.Centre bolt 2 has a section of square shank 11, which can slide through but not rotate within rectangular section hole 12 formed in clamp half la. The bolt has a head 13 which in operation tilts on fulcrum 14 formed in I a. The spherical seatings 6 are largely cut away by grooves 7 and 8, and reduced further in area by spherical undercut 15, so that the 4 remaining pads 6 are of quite limited area, the better to grip the ball end. Knob 3 bears via load-spreading washers 16 and friction reducing plastic washer 17 on fulcrum 14 of clamp half lb. 2/2 Figure 4 shows the ball clamp in its double ball clamp configuration. The configuration for connecting tubes using the v grooves is self evident and not shown.

Figure 5 shows a possible configuration of the clamp for mounting (for example) a microphone or camera (fitting the threaded rod end) to a tube or other item (not shown) Various alternative embodiments are practical. The clamp halves can be pressed rather than cast ( or made by any suitable means) the seatings can be annular rings rather than seatings with a spherical surface, the clamp halves need not be symmetrical as shown here, and they need not be identical -there could be top and bottom halves having some different details (for example around the centre bolt). The central means for drawing the halves together may have any form of shank provided it can he prevented from rotating in the clamp half by a suitable matching hole form. Alternatively the head may be shaped to prevent turning (a square shaped head for example). Alternatively again, a T shaped shank formed from flat can be used as described in the earlier application mentioned above. There may be a plurality of means for drawing the halves together. The return spring (or springs), provided the load is applied offset as described, can have many forms -for example offset coil springs, or external elastic around the pivot end, or springs formed from flat.

Claims

Claims What I claim is: 1. A clamp comprising two clamp halves, one or both of which incorporates or is associated with various first means adapted to accommodate or grip part of another article, clamping means adapted to draw the halves together and third means adapted to cause two of the clamp ends adjacent to each other to move towards a closed position.
2. A clamp as claimed in claim 1 where the third means is a return spring in conjunction with means to secure the spring ends to the clamp halves.
3. A clamp as claimed in claim 2 where the means to secure the spring ends comprises recesses in the respective faces of the clamp halves.
4. A clamp as claimed in any preceding claim where the return spring is a Q centrally housed double torsion spring which acts in co-operation with the clamping means both to hold the halves apart at one end and tilt them so that they can close upon another object at the other end.
5. A clamp as claimed in any preceding claim where the means adapted to grip or accommodate another article comprises one or more seatings associated with one or both of the clamp halves.
6. A clamp as claimed in any preceding claim where the means adapted to grip or accommodate another article comprises in addition or in the alternative one or more grooves in one or more of the faces of the clamp halves, optionally intersecting any seatings
7. A clamp as claimed in claim 6 where the grooves are V-shaped in cross-section.
8. A clamp as claimed in any preceding claim where the halves close upon a ball or cylinder at one end so as to form a pivot.
9. A clamp as claimed in any preceding claim where the opposed ends of the clamp halves are constrained to open and close with the operation of the clamping means.
10. A clamp as in any preceding claim where the clamping means comprise a threaded bolt with mushroom head and square shank, the threaded section engaging a thumbwheel nut or other device for tightening the clamp.
11. A clamp as in claim 11 where the thumbwheel nut acts via a thrust bearing.
12. A clamp as in claim 12 in which the thrust bearing comprises two steel washers with a washer of PTFE or other plastics material sandwiched in between.
13. A clamp as described in any preceding claim in which all or some of the seatings and grooves are omitted.
14. A clamp as described in any preceding claim in which the dimensions or shape of the halves are different.
15. A clamp substantially as described in the description and drawings. Co Co

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