GB2061441A - Safety Guard for Portable Powered Drilling Machines - Google Patents

Abstract

A safety guard for use with portable drilling machines comprises a chuck guard E which can be adapted to different makes of machine and which can be easily and quickly removed and replaced for the exchange of drills and tools, together with a transparent or substantially transparent tool guard which slides telescopically on the chuck guard and which may be adjusted in position relative thereto. <IMAGE>

Description

SPECIFICATION Chuck and Drill Safety Guard for Portable Electrically Powered Drilling Machines The Technical Field This invention relates to the technical field of portable electrically powered drilling machines intended for use in either or both hand-held or drilling machine stand operations by the homecraftsman and self-employed tradesman and others in the 'Do-it-Yourself' field, and the objective of the invention is to improve the safety to the user of such powered hand-tools by the provision of a Chuck and Drill Safety Guard which may be adapted to any such machine or to its drill-stand.

Whilst it is common and accepted practice, and indeed a Statutory obligation under the Health and Safety at Work Act, 1974, for powered drilling mchines of pillar type fixed to the bench or floor in the prior industrial art to be rendered 'as safe as is reasonably practicable' by the provision of a Safety Guard, it does not appear to be recognized that portable powered drilling machines present no iess, and possibly greater, hazards to the user.The reasons for this is that apart from the risks generally associated and recognised in the operation of a fixed pillar type powered drilling machine, the user of a portable hand held electrically powered drilling machine is free to operate it in any dimension, often in awkward places under primitive conditions, on a variety of materials using special tool-bits, other than drills, which were not primarily designed for use in a drilling machine.

The Background Art The Inventor would refer to the book 'Power Tools at Home' (ISBN: 0 900 727268) by Harold King published in the TV Times Family Book series, in which the use of portable electric drilling machines with their attachments for use on timber, masonry, concrete, ceramics, glass, plastics and metal is described and profusely illustrated. Although there are chapters in the book titled 'The art of drilling' and 'Safety First' there is no mention, description, or illustration of a Chuck and Drill Safety Guard in use on a portable electric drill, and nor is such a Safety Guard listed in the Glossary amongst the attachments and accessories available to the user.

Reference may also be made to crafts magazines amongst which might be mentioned 'The Practical Woodworker'; 'Practical Householder' and 'The Woodworker' and to standard text-books such as 'Woodwork' by David Willacy (ISBN 0 17 431017 X) used in schools which recommends only that goggles should be used when operating pillar-type drilling machines.

The most recent press advertisement seen by the Inventor (Express 8 Star, Wolverhampton) in October, 1979, extols a portable powered drilling machine as 'lighter, quieter, safer and more precisely built than the more familiar names' yet as regards to safety illustrates only a handle for better grip fastened to the spindle nose of the drilling machine above the chuck but nowhere is a Chuck and Drill Safety Guard featured at all.

Disclosure of the Invention Essentially the invention comprises a rigid tube, or partial tube, henceforth referred to as the 'Chuck Guard', together with a transparent tube or semi-transparent tube, or segment thereof, henceforth referred to as the 'Drill Guard', with means provided to extend and retract the drill guard in a telescopic manner and to fasten it on the chuck guard according to the position required. The chuck guard is provided with a variety of adaptors in the form of collars, carrier plates, or clamps, to enable it to be fitted to any type of portable drilling machine for hand held use or for use when the machine is temporarily fixed into a stand designed for use with a portable drilling machine or, alternatively, the chuck guard may be attached to the drilling machine stand.A feature of the chuck guard is that it can be easily removed and replaced on the drilling machine itself or on to its adaptor in order that the chuck can be operated by its key or a hole is provided in the chuck guard, so that drills and tools may be inserted and removed.from the chuck. When the chuck guard is fitted directly to the spindle nose of the machine or to an adaptor being a collar, it may be placed in a revolved position so that the drill guard affords protection to the user from abraded materials or broken tools in the position in relation to the machine at which he is working and, additionally, the chuck guard serves to collect fragments of abraded material from the work-piece when the user is operating the machine above his head.The chuck guard serves to provide better balance and stability to hand held drilling machines as it enables the user to grasp the chuck guard more closely to the point of entry of the drill or tool into the work-piece, thus giving him greater control of the machine and over the operation which he is carrying out. The chuck guard, or its adaptor, may be provided with a handle but control is as well exercised by the simple expedient of holding the chuck guard itself.

Whilst the tubes, or segments thereof, referred to for the making of the chuck and drill guards may be of circular form, the invention does not exclude tubes which may be of square, rectangular, or other section. In general a sufficiently strong and rigid material is provided for the drill guard without need of an enclosing framework of metal but such a framework may be provided.

Certain types of portable drilling machine are supplied by manufacturers on which the chuck is larger in diameter than the part of the drilling machine to which an adaptor in the form of a collar can be fitted without removing the chuck. In such cases an internal collar is provided to the chuck guard and, once fitted, the collar may remain in position after the replacement of the chuck as it is possible to siide the chuck guard on to its collar and to remove it at will. A chuck Remover may be supplied with the Safety Guard for the removal of obstinate chucks from their spindles. The Chuck Remover comprises a collar with a threaded hole across its diameter through which a stud-ended screw on a substantial plain shank can be entered into one of the chuck key orifices when placed on the nose of the chuck.

The plain end of the shank of the Chuck Remover may be struck repeatedly, instead of the chuck key as suggested by manufacturers of portable drilling machines, without fear of hitting the chuck and of damaging its spindle or of losing the chuck key.

Description of the Figures in the Accompanying Four Drawings In order that the invention and the manner of adapting it to different makes of portable drilling machine or to their stands may be understood, embodiments of the Chuck and Drill Safety Guard with its various adaptors will now be described with reference to the figures in the accompanying drawings.

Figure 1 shows an assembly drawing of a Chuck and Drill Safety Guard in the preferred form, together with its adaptor collar. Figure 2 shows an assembly drawing of a rotated view with the drill guard in a retracted position. Figures 3, 4, 5, 6 and 7 show the components of the Chuck and Drill Guard and its internal adaptor collar. In all of the preceding figures each component part is correspondingly identified with the same alphabetical letters.

'A' shows a section through a circular collar adaptor which is attached to the spindle casing on the nose of a portable drilling machine by the setscrew 'B'.

'C' is a set screw, or threaded dowel, with means provided 'D', which may be a handle, to fasten the tubular chuck guard 'E' to the collar through slot 'F' in the chuck guard. A similar slot 'F' on the opposite side of the chuck guard provides clearance for the set-screw 'B'. The chuck guard may be fully rotated to engage through the slots 'F', or through any additional slots in the guard, over both set-screws 'B' and o 'G' is a set-screw, or threaded dowei, secured to the wall of the chuck guard or is a headed screw passing through the wall of the chuck guard, with means provided 'H' to fasten the drill guard 'I' through its slot 'J' in the position required on the chuck guard according to the length of the drill required for the depth of the hole needed in the work-piece.Alternatively the drill guard may be allowed to slide in its slot in telescopic manner. The drill guard may be a complete tube, or segment of a tube, with its end shaped as in 'K'. The chuck guard may be easily removed and replaced on its collar for the insertion and exchange of drills with the chuck key by slackening and tightening the nut or handle 'D'.

On some types of portable electric drilling machines an internal collar is unnecessary as the chuck guard can be placed on to the spindle nose of the machine with a push-fit when the spindle nose is larger than the chuck. If necessary, slits can be provided on the end of the chuck guard which fits on to the spindle nose to enable the guard to be clamped on to the nose by an exterior collar around the chuck guard, and the collar may be provided with a handle as shown in Figure 11 at 'P'.

Figure 8 shows an alternative arrangement of an assembly of components illustrated in Figures 9, 10 and 11 which permits the Safety Guard to be attached on to the body or case of a portable drilling machine which is to be either hand held or fixed into a drilling machine stand. Figure 9 shows a yoke, arbor or cradle 'L' which can be fixed to the body or case of the machine by a set-screw 'M' or a bolt, and 'N' is a means of fastening a carrier-plate '0' in Figure 10 to an external collar illustrated in Figure 1 1 and which may be provided with a handle as at 'P', or is closed around the chuck guard by a screw and nut.

Alternatively the yoke may be dispensed with by fastening a carrier plate to hold a collar, or the chuck guard itself, directly on to the body of the machine by a bolt secured into a drilled and tapped hole in the machine's case.

A variation from attaching the Safety Guard on to a portable drilling machine is to attach the chuck guard on to the machine's drilling stand.

Figure 12 shows the underside of the yoke of one such stand art '0', an examination of which has revealed a groove in the yoke's casting webs of parallel depth and width as shown by section 'R' indicated by the arrows. This groove subtends an arc of 1200 as shown by the shaded arc, into which a substantial part of the end of the chuck guard is shown in location. The end of the chuck guard may have to be notched in appropriate places to accommodate certain parts of the yoke, as shown in Fig. 1 3 at 'S'. The guard may be held in position on the yoke as shown in the enlarged sectionalised view by a pin as in Figure 14 or by a rebated collar or clamp as in Figure 15.

The Best Mode for Carrying Out the Invention The best mode for carrying the invention into effect will now be described with reference to the preferred form of Safety Guard for use with a hand held powered portable drilling machine. The material for the chuck guard may be made from metal or plastic tubing cut to length to project to the end of the chuck jaws when in the closed position. The slots 'F' in Figures 1 and 2 may be made with a press tool in metal material or by drilling and sawing plastic material. The drill guard is best made from 'Perspex' (Registered Trade Mark) tubing or formed from flat Perspex sheet. The slot 'J', Figures 1 and 2, in the Perspex segment is best drilled and milled on a suitable jig after forming the required shape. Adaptor collars for the chuck guard may be cast in metal but it is expedient to cut off pieces from a pipe of the required diameter for machining on a lathe.

Whilst the yoke shown in Figure 3 is illustrated in pressed steel, manufacturers of portable drilling machines may like to consider the possibilities of casting attachments for Chuck and Drill Safety Guards to be secured on to their particular machines by a bolt.

Exploitation Reference has been made briefly to the Health and Safety at Work Act, 1974, effective in the U.K. upon Suppliers and Users of industrial machine tools. There is little doubt that E.E.C.

countries and others operate similar regulations or will do so.

The manufacture and marketing of portable electrically powered drilling machines for both home and industrial use is an industry in itself.

Such tools are widely used not only by the home craftsman but by many self-employed carpenters and builders and in other trades. It may have been that manufacturers of portable powered drilling machines have in the past taken the view that such tools are not generally intended for industrial use and have, therefore, no need to comply with the Health and Safety at Work Act. Certainly none of the advertisements in the press or catalogues of attachments and accessories supplied by manufacturers of portable drilling machines list Chuck and Drill Safety Guards amongst the items which can be purchased to suit their machines, even though some such portable drilling machines are described as suitable for industrial usage.

There is good reason why home craftsmen and the small tradesman should be protected as far as is reasonably practicable from the hazards of using portable electrically powered drilling machines without a Safety Guard. The home craftsman may be untrained in Safety Precautions and unaware of the dangers in using powered hand tools. Simply bacause accidents in the home do not have to be reported as in industrial cases does not render them less frequent or severe in consequences. The small tradesman aften has to work in awkward positions and primitive conditions and if he sustains injury he may lose his livelihood.

The Inventor is concerned about the provision and supply of portable electric drilling machines without Safety Guards and it is to be hoped that the manufacturers of these products will realise that they will be rendering a public service by making Safety Guards a mandatory requirement in the provision of electrically powered drilling machines by their Distributors to Customers. In doing so manufacturers will improve their image and increase their sales. Manufacturers who fulfil a mandatory requirement by the Patentee as a Condition Precedent upon Distributors and Suppliers of their portable electric drilling machines that such tools shall be provided with a Safety Guard of the type substantially as described and illustrated in this Specification shall be entitled to exercise this Patent upon generally agreed terms within the portable electrically powered hand-tool industry and, hence, this Patent is to be endorsed 'Licence of Right'.

Claims (9)

Claims

1. A Chuck and Drill Safety Guard for use with hand-held portable electrically powered drilling machines for the protection of the homecraftsman, self-employed person, or other user, when working on timber, metal, masonry, concrete, ceramics or glass with a drill or other tool bit characterized by a Chuck Guard of tubular form which can be attached directly on to the spindle nose of the drilling machine or be attached thereto by means of an adaptor, being a collar, clamp, or carrier-plate; together with a Drill or other tool Guard of tubular form or segment thereof in transparent or semi-transparent material which slides telescopically on the Chuck Guard with means provided to fasten the Drill Guard in position on the Chuck Guard as required.

2. A Safety Guard as claimed in Claim 1 but for use with portable electrically powered drilling machines when either hand-held or when held in a stand for a portable drilling machine, as opposed to pillar drilling machines of bench or floor-standing type for heavy industrial use, wherein the Chuck Guard is attached directly to the portable drilling machine by means of a yoke, arbor, or cradle, shaped to the body or case of the machine, and attached to the chuck guard by means of a carrier-plate, collar, or clamp, or directly to the chuck guard.

3. A Safety Guard as claimed in Claims 1 and 2 in which the chuck guard is secured directly to the body of a portable drilling machine, or by means of a carrier-plate, collar, or clamp, by a bolt fastened into a hole drilled and tapped in the casing of the machine,

4. A Safety Guard as claimed in Claim 1 but for use when a portable drilling machine is held in a drilling machine stand designed for that purpose by a yoke, arbor, or other device, on to which the chuck guard may be directly attached, or by means of a collar or clamp.

5. A Safety Guard as claimed in Claim 1 but wherein the drill guard forms an integral part of the chuck guard.

6. A Safety Guard which is a Chuck Guard alone and without its drill guard, as hereinbefore described.

7. A Safety Guard as claimed in any of the preceding Claims to which a handle is attached, or is attached by means of a collar, or clamp.

8. A Safety Guard as in any of the preceding Claims provided with a Chuck Remover as hereinbefore described.

9. A Safety Guard substantially as hereinbefore described and as shown in the accorrlpanying drawings.