GB2252805A

GB2252805A - "Misalignment compensating washer"

Info

Publication number: GB2252805A
Application number: GB9121514A
Authority: GB
Inventors: Aidan Mark Thomas Chippendale
Original assignee: George Clark
Current assignee: George Clark
Priority date: 1990-10-16
Filing date: 1991-10-10
Publication date: 1992-08-19
Also published as: GB9022430D0; GB9121514D0

Abstract

The washer 20 has a frusto-conical portion which fits within an aperture in a bracket 3 and the washer 20 also has an aperture which is eccentric in relation to its flange which engages the bracket around its aperture, so that the nut 26 and bolt 7 clamp the bracket 3 adjustably to the beam 4 to compensate for any misalignment of the bracket 3 and the beam 4. The aperture in the bracket 3 comprises two (or more) intersecting circles (or trapeziums), and the frusto-conical portion of the washer fits into a selected circle. The flange is of hexagonal form. <IMAGE>

Description

"Cam Washer Adjusting Device" This invention relates to a means of location adjustment when fixing one member to another member.

For fabrication purposes it is a common practice to prepare each member for fabrication in a factory prior to delivery to a site where construction or assembly may take place. Preparation of the members may include cutting each member to its required length and also drilling any number of holes through the members for fixing and/or assembly purposes. For many reasons it is often difficult to know the exact location that such holes should be drilled, as the conditions of the assembly site may not be completely known. In such a case it is preferable to have an adjustment means whereby the fixing of two members at the location of a hole drilled for that purpose may be adjusted en situ.

There are many examples of where location adjustment means may be required and these include the assembly of furniture, fencing, walkways and platforms and the like. Another particular example is in the support of a brick fascia on the outside of a large modern concrete building. A common method used to support single width brick walls in high rise buildings is by the provision of metal brackets being fastened to a fixing means protruding from a concrete wall. These brackets support elongate horizontal plates which fit between adjacent courses of bricks in the cladding.

The weight of the bricks is thus transferred to the concrete. As the brackets must be accurately positioned so that the plate supports are provided at the correct height, the precise location of the brackets should be adjustable in height relative to the fixing means, such as a bolt, extending from the concrete.

In the past, it has been common to provide a slot, or elongated hole in the bracket such that the fixing means may be adjusted relative to the bracket by locating the bolt or fixing means in various positions within the slot. However, a common problem of this is that should the fixing means be even slightly loosened, the bolt tends to slip within the slot because of the load on the bracket and accompanying elongated plate.

One idea to prevent the slippage of the fixing means within a slot in the bracket is to provide serrations on the inside walls of the bracket which mate with a locking means also having serrations of similar pitch.

The mating of the serrations prevents slipping of the bracket. However, with this method the increments of adjustment are conditional upon the pitch of the serrations. As the pitch of the serrations is reduced the likelihood of slippage is increased and thus it is not practical to have very small increments whereby location may be adjusted.

According to the present invention there is provided a means of location adjustment comprising a first member for attachment to a second member and apertured to allow passage for a bolt or other fixing means, a lock member having a first portion which fits within the aperture of the first member, the lock member also having a second portion which extends beyond the aperture so as to be clamped against the first member by application of a nut or the like to the fixing means in use, and the lock member also having a through hole to allow passage of the bolt or fixing means, wherein the lock member is rotatable within the aperture of the first member about a first axis and the fixing means is rotatable within said through hole of the lock member about a second axis, and the first axis is offset from the second axis.

Preferably, a plurality of the apertures through the first member are provided. Such apertures may merge together to provide a single aperture having a cross section repeating along the aperture so that the lock member can be fitted within the aperture and held therein in alternative positions. The distance across the intersection of adjacent merged apertures is preferably less than the distance across the first portion of the lock member so that after insertion the lock member is held in one section of the aperture.

Preferably, the second portion of the lock member is of a profile which allows engagement by a normal wrench or spanner for rotation of the lock member.

Preferably, each repeating cross section of the aperture in the first member provides clearance in at least one direction around the first portion of the lock member.

An embodiment of the invention will now be described, by way of example with reference to the accompanying drawings, in which: Fig. 1 is a front view of a location adjustment means in accordance with the invention; Fig. 2 is a section of a side view of the location adjustment means in accordance with Fig. 1; Fig. 3 is a front view of a lock member in accordance with the invention; Fig. 4 is a side view of the lock member in accordance with Fig. 1; Fig. 5 is a front view of an aperture in a first member having a non-uniform repeating cross section; and Fig. 6 is a second embodiment of the first member having an alternatively shaped aperture.

Referring now to the drawings, a bracket or first member 3 is required to be supported by an elongate beam or second member 4, at a precise location. A bolt 7 extends through a hole in the beam 4 and subsequently through an aperture 8 in the bracket 3. The stem of the bolt 10 extends outwardly from the beam 4 through the aperture 8 in the bracket. A lock member 20 is fitted over and around the stem of the bolt 10 such that a first frustoconical portion of the lock member 20 is also housed within the aperture 8 in the bracket and a second larger-diameter portion of the lock member 20 is held against the outside face of the bracket. A nut 26 is then screwed onto the bolt 7, thereby securing the lock member 20 from movement in an axial direction along the bolt.

The aperture 8 has a profile in accordance with a series of intersecting circles in a vertical direction, as shown in Fig. 5. Accordingly, the circular profile may be said to be "repeating" along the aperture. The diameter of the repeating circular profile is larger than the first portion of the lock member 20 but the distance across the intersection of adjacent circles is smaller than the diameter of the first portion of the lock member. Thus, the first, frustoconical portion of the lock member which circumnavigates the stem of the bolt 10 may be located with some freedom within a particular repeating portion of the aperture 8 and held therein against slippage.

The second portion of the lock member 20 is larger in cross section than a repeatable section of the aperture in the first member and is therefore unable to pass through the aperture in the first member. Thus, by locating the first portion inside the aperture, the second portion remains against the outside face of the first member.

A first method of adjustment of the bracket 3 relative to the beam 4 is provided by locating the stem of the bolt 10 in any of the alternative repeating profile sections in the aperture 8.

The lock member 20 is also provided with a through-hole 21 to allow passage of the bolt stem 10 therethrough.

The through-hole is not concentric with the first portion of the lock member. (Similarly, should the first portion of the lock member not be of circular cross-section the centre of the through-hole is offset from the centre of the first portion. Thus, upon rotation of the lock member, the location of the through-hole moves relative to the location of the first portion of the lock member in the aperture 8 of the bracket 3.

As rotation of the lock member 20 is about the stem of the bolt 10, the location of the circumference or perimeter of the first portion of the lock member 20 will vary in accordance with the angle of rotation of the lock member. Thus, rotation of the lock member 20 causes the wall of the first portion of the lock member 20 to act as a cam against the wall of the aperture 8 in the bracket 3. This cam action of the first portion of the lock member 20 provides a means of fine adjustment for locating the bracket relative to the beam 4.

Rotation of the lock member 20 may be achieved by gripping the second portion of the lock member and consequently, the second portion has a hexagonal profile to accommodate a normal open-ended spanner.

In an alternative embodiment of the invention the first portion of the lock member may be cylindrical or non-tapered.

In another alternative embodiment the aperture in the first member is trapezoidal, wherein the non-parallel sides of the aperture profile are tapered inwards.

Such a profile may also be repeated along the aperture, again so that the lock member can be fitted within the aperture in alternative positions. This is shown in Fig. 6.

In use, the first member may be secured to the second member by passing the stem of a T-headed bolt through the aperture in the first member and subsequently through the through-hole in the lock member. The lock member is presented to the first member so that the first portion or boss of the lock member fits within the aperture. If the location of the first member is significantly removed from a required location, relative to the second member, the lock member is removed and the first member is adjusted so that the bolt and lock member is located in an alternative repeating section of the aperture. This provides coarse adjustment.

Once the first member is located relative to the second member in the most appropriate repeating section, fine adjustment may be achieved by rotation of the lock member. Rotation of the lock member will cause the surface of the first portion or boss to act on the inside walls of the aperture causing the first member to move relative to the second member. Once the first member is in the exact desired location relative to the second member, a nut screwed onto the bolt stem may be tightened against the lock member to maintain the arrangement and location.

It is realised in the invention that the axis of the aperture in the bracket or first member need not be vertical but may be horizontal or in any inclined direction, depending on the direction of adjustment required. Furthermore, the aperture may be of various sizes to accommodate different bolt sizes and different cross sectional areas of the first portion of the lock member. The magnitude of the clearance between the aperture and the circumference or perimeter of the first portion may also be varied in accordance with the extent of adjustment which may be necessary.

Similarly, the number of repeating sections within the aperture may be varied and the distance between repeating sections, that is the extent to which the repeating sections overlap in relation to their size, may also be designed to suit a particular need. All of these sizes and distances may be regarded as variables when designing the extent and degree of adjustment of a first member relative to a second member in respect of coarse adjustment from one repeating section to another, or fine adjustment by rotation of the lock member.

It is a considerable advantage of the present invention that an exact location may be obtained by rotation of the lock member. Previously, location adjustment means for this purpose have been limited to incremental adjustment.

The system as described above may also comprise more than two members which are to be fixed together. For example, a further beam may be added to the joint and this beam may also have an aperture with repeating sections to enable location of the beam to be adjusted also, relative to the first member and the second member.

Modifications and improvements may be incorporated without departing from the scope of the invention.

Claims

1. A means of location adjustment comprising a first member for attachment to a second member and apertured to allow passage for a bolt or other fixing means, a lock member having a first portion which fits within the aperture of the first member, the lock member also having a second portion which extends beyond the aperture so as to be clamped against the first member by application of a nut or the like to the fixing means in use, and the lock member also having a through-hole to allow passage of the fixing means, wherein the lock member is rotatable within the apertiire of the first member about a first axis and the fixing means is rotatable within said through hole of the lock member about a second axis, and the first axis is offset from the second axis.

2. A means as claimed in Claim 1, wherein a plurality of apertures are provided through the first member.

3. A means as claimed in Claim 1, wherein the aperture in the first member is of non-uniform cross-section and comprises first portions whose cross-section is sufficiently large to allow insertion therein of the first portion of the lock member, and second portions whose cross-section is insufficiently large to allow such insertion.

4. A means as claimed in Claim 3, wherein the aperture has a repeating regular profile of successive first and second portions.

5. A means as claimed in Claim 3 or 4, wherein the first portions are part-circular.

6. A means as claimed in any one of the preceding claims, wherein the second portion of the lock member has straight sides for engagement with a wrench or spanner.