GB2201616A - Device for holding planar objects - Google Patents

Abstract

A portable device for holding planar objects such as doors in a given edgewise relationship to a working surface comprises a pair of spaced apart parallel plates (6, 7,) means such as an externally threaded shank (9) passing through co-operatively internally threaded bush (10) rotatably fixed at its end to plate (7) and operable by means of tommy bar (11) to adjust the spacing between the plates, base member (1) and means of attachment of the plates to the base member such as neck (2). In use the base member may be laid on the working surface and an edge of the planar object inserted between the plates and held therein by suitable adjustment of the plates, thereby holding the planar object in a given edgewise relationship to the working surface, to facilitate work operations thereon. <IMAGE>

Description

DEVICE FOR HOLDING PLANAR OBJECTS This invention relates to a portable device which is intended to assist the handiman or craftsman who desires to perform work operations on a relatively large planar object held in a given edgewise relationship to a working surface.

Performing work operations on relatively large planar objects such as doors, shutters, sheets of blockboard, chipboard or plywood or the like presents problems to the individual handiman or craftsman. Certain operations, such as the planing of an edge or the fitting of mortice locks or hinges are most readily performed while the object to be worked on is held in edgewise relationship to a work surface. To achieve this the individual craftsman will usually resort to the expedient of using a saw horse having a vertical slot into which slot an edge of the object to be worked on can be inserted, an adjacent edge resting on the working surface, the saw horse acting to hold the object on an approximately vertical relationship to the working surface.However, the sa horse itself often requires to be stabilised and, to fit the object firmly into the slot, a wedge may be required which can easily damage delicate such as doors made of sapele wood, which is particularly prone to damage, or objects which have already been painted or varnished which, if a high standard of workmanship is required, may have to be entirely repainted or revarnishea to hide localised damage.

The home handiman, to achieve a similar object, may resort to the expedient of using a portable workbench such as a Workmate ('lAtorkmate' is a Trade Mark) by tightening the jaws of the bench on to an edge of the object to be worked while resting vertically in edgevise relationship to the working surface. The jaws of portable work benches are typically narrow in cross section and give little stability to the object to be worked and are also prone to cause damage to the object if tightened on to it to increase stability.

The expedients referred to above also suffer from the disadvantage that since the lower edge of the object rests directly on the working surface the entire vertical edge cannot be planed without withdrawing the object from its support, inverting it with the opposite edge downwards and refitting it on to its support which procedure only increases the possibility of damage and makes it necessary to plane against the grain of the wood at least to some extent.

according to the present invention there is provided a portable devicefor holding a planar object in a given edgewise relationship to a working surface to facilitate the performance of work operations thereon, the device being characterised by a pair of spaced apart parallel plates, means for adjusting the spacing between the plates to provide a releasable grip on a planar object between the plates, a base member for resting on a work surface the base member being attached to the plates and extending transversely on both sides of the plane thereof, and the means of attachment of the plates to the base member being capable of holding the plates in the desired edgewise relationship to the work surface.

The term 'in edgewise relationship to' is used to denote that an edge of the object to be worked on is presented to or towards the working surface, the object usually being vertical to the work surface but optionally being at another angle usually greater than 60deg. to the working surface.

The device according to the invention may conveniently be constructed of mild steel, or any other suitable metal, of a gauge suitable to give the required structural strength and rigidity to the various component parts. The base member, hitch may be a simple bar member in, for example, square or rectangular tubing, may carry the plate rigidly attached to an upstanding neck of similar tubing attached to the base member intermediate to the ends thereof.The pair of parallel plates may be incorporated in an assembly comprising a channel shaped member the base of which is rigidly attached to the end of the upstanding neck in a plane normal to the axis of the neck with the sides of the channel extending on the side of the base remote from the neck member, one side of the channel member comprising one plate and the other plate lying within the channel, parallel to and mounted on the second side of the channel.A convenient means of providing for adjument of the spacing between the parallel plates is to mount the second plate on a threaded member extending normal to the plate and axially rotatable relative thereto passing through the second side of the channel member and coacting with a mating thread in the channel member whereby on axial rotation of the threaded member the coaction of the mating threads acts to alter the spacing between the plates. The inner surfaces of the parallel plates are preferably covered with a layer of slightly resilient material, such as for example a layer of vinyl polymeric material,to give protection to the object to be held without being so unduly resilient as to reduce the firmness of the grip on the object.

Preferably the base member is fitted with a leg at each end, preferably pivotally foldable into a nesting relationshp with the base member on the side pf the base member remote from the neck member, and capable when opened of supporting the bottom of the channel member and therefore the lower edge of the object to be worked on, at its point of support, at between 1Ocm and 40cm particularly preferably 12cm to 30cm above the work surface.

The size and conformation of the inner surfaces of the parallel plates is of importance in preventing damage.

Preferably the inner surfaces of the plates, which need not be of equal size, are each at least 25 sq.cm. particularly preferably at least 30s.cm. and very suitably at least 40sq.cm. in area and up to for example 150sq.cm. in area or even more and preferably have a smallest dimension of 4cm.

particularly preferably of at least 5cm. for example, very suitably at least 6cm. Plates of such a size, which covered on their inner surfaces by a slightly resilient material such as, for example, polyvinyl chloride sheet material of, for example, at least 0.25mm. preferably at least 0.4mm. very suitably at least 0.5mm. in thickness or up to, for example, 1.55mum. or more, can be tightened on to even relatively delicate woods, or wood surface finishes, sufficiently to give firm support with a reduced tendency to cause damage.

It is understood that the device according to the present invention may be modified within the general principles outlined above according to the requirements of a particular end use. For example the plates may be fixed at an angle departing from normality with respect to the base member, or may be made angularly adjustable with respect to the base member, for example by means of a ball and socket connection fitted with threaded tightening means. The means for adjusting the spacing betwen the plates may also, for example be provided with torque sensitive means to prevent over tightening. The neck member may be absent. The base member may provide stability in more than one plane.

A particular embodiment of the invention will now be described by way of example only with reference to the attached drawings. Fig. 1 is a perspective view. Fig. 2 is a verical section on line AA of Fig. 1. Fig. 3 is an elevational view from one side of the device according to the invention in use. The device depied in the drawing consists of a base member I fabricated from 2.5cm.cross section square mild steel tubing of 0.1cm. thickness, a neck member 2, 6.5cm. long fabricated from the same tubing welded to the base member and a channel member 3, fabricated from sheet steel of 0.5cm. thickness and incorporating the plate assembly welded to the neck member, having sides 4 and 5.The dimensions of the channel member are a length of 9cm. a base width (internal) of 6cm. and a height (internal) of 7cm.

The plate assembly comprises a fixed plate 6 which is provided by side 4 of the channel member, and a movable plate 7 which is mounted on side 5 of the channel member. The mutually facing surface of each plate is covered by a sheet s vinyl polymeric sheet material 8, which may be, for example, floor tiling material, fixed thereto by means of a suitable adhesive. Plate 7 is mounted on the relevant side of the channel member by means of externally threaded member 9 fitted within internally threaded member 10 and protruding through member 10 and through the side 5 of the channel member and being attached to but axially pivotal with respect to plate 7.

It is seen that relative rotation between members 9 and 10 acts, in use, to alter the spacing between the plates. The outer esu ui bne member y is proi(iQC(1 ij1 a slidable bar II to facilitate operation.The detailed construction of plate 7 and its mounting on channel side 5 is shown in Fig.2 in which thin cover plate 12 is shown bonded to thick backing plate 13 having a cavity 14 and a bore 15 through which a narrowed shank 16 of member 9 protrudes and is held in position by washer 17 over which the end portion of 18 of shank 16 has been flattned to an extent sufficient to prevent withdrawal of the shank but not to prevent axial rotation of the shank relative to the remainder of the plate assembly. Pivotally fixed to the ends of base member 1 are foldable legs 19 in channel section mild steel 0.2cm. in thickness the legs being 21.5cm. long from the pivotal points 20.

In use if a door or other planar object 21 shown in part in Fig. 3 is placed between the plates and held there by suitable operation of the adjusting mechanism it may be supported edgewise in relation to a working surface 22 as shown in Fig. 3 the device according to the invention giving lateral stability and the planar object itself, by impinging on the work surface at one end, giving stability in a longitudinal direction. By virtue of one end of the object 23 being held clear of the work surface and at angle operation such as planing are facilitated.

Claims (6)

1. A portable device for holding a planar object in a given edgewise relationship to a working surface to facilitate the performance of work operations thereon, characterised by a pair of spaced apart parallel plates, means for adjusting the spacing between the plates to provide a releasable grip on a planar object between the plates, a base member for resting on a working surface, the base member being attached to the plates and extending transversely on both sides of the plane thereof, and the means of attachment of the plates to the base member being capable of holding the plates in the desired edgewise relationship to the work surface.

2. A device as claimed in Claim I wherein the base member is provided with legs capable of being moved between folded and extended positions which in the extended position are adapted to hold the base member above the work surface.

3. A device as claimed in Claim 1 or 2 wherein the plates are each at least 30sq.cm. in area with no transverse dimension being less than 4cm.

4. A device as claimed in any preceding claim wherein the plates c cov-orea on tnelr innermost surfaces with a sheet of a vinyl polymeric material.

5. h device as claimed in Claim 1 and substantially as described herein.

6. A device substantially as described herein with reference to Figures 1 or 2 of the accompanying drawings.