GB2203069A

GB2203069A - Drill jig

Info

Publication number: GB2203069A
Application number: GB08707717A
Authority: GB
Inventors: Ian Malcolm Robertson
Original assignee: Channelwood Preservations Ltd
Current assignee: Channelwood Preservations Ltd
Priority date: 1987-04-01
Filing date: 1987-04-01
Publication date: 1988-10-12
Anticipated expiration: 2007-04-01
Also published as: GB8707717D0; GB2203069B

Abstract

A drill jig for drilling a wooden window frame has two elongate base portions (10, 12) and a clamp (14) pivotally mounted on one of the base portions. Each base portion is provided with a tubular drill guide (30) which is movable along the axis of its respective base member and which is securable by means of a bolt (33) which is adapted to bear against a bar (28) connected to the tube. In use, the device is affixed to the corner of a window frame by clamping the clamp (14) onto one of the frame members and the tubular guides (30, 30') are adjusted so that they lie over the centre of the respective frame member to be drilled. <IMAGE>

Description

DESCRIPTION DRILL JIG.

The present invention relates to drill jigs, and in particular to drill jigs for use in drilling bores in a frame having two frame members inclined to other, such as may be found in window sashes.

It is known to treat window frames with preservative by drilling one or more holes in the window frame and inserting preservative into the holes. The holes can either be made along the window frame members or can be composed of a plurality of short, intersecting, inclined channels which form one continuous channel, into which the fluid preservative is introduced.

GB 2113282A discloses a method and apparatus for treating a wooden window frame with a preservative, in which the members making up the frame are drilled from their surfaces at predetermined locations along the length thereof to form bores, at least some of which are angled so that the bores intersect to form a continuous channel, and into which a fluid preservative is introduced, thereafter the channel is closed off. Theapparatus disclosed in that specification is used to guide a drill bit to drill a longitudinal bore down approximately the centreline of a particular frame member, or at a point where it will be equidistant from opposite edges of the member. In use, the jig is firmly clamped onto one of the frame members to allow the drilling of the longitudinal bores to take place.The jig is then removed and attached to a different member, and the operation is repeated. By attaching the jig to each corner of the frame in turn and drilling the corresponding bores, all four frame members of the frame may be provided with such a bore, whereupon fluid preservative may be inserted therein.

GB 2130936A discloses a drill jig for forming an inclined bore in a substantial wooden member such as a window frame member. The device disclosed therein comprises a body formed with an inclined through guide bore and being provided with a location spigot adapted to be received in a bore formed in the wooden member to be drilled. This drill jig is primarily concerned with forming a series of blind locating bores in a length of timber to be drilled, the blind bores intersecting and forming a common continuous channel in the frame member.

However, the above devices suffer from the disadvantage that they can not successfully be used on members of relatively thin cross-section, such as may be found in a window sash, since this would weaken the sash to an unacceptable extent.

In accordance with the present invention there is provided a drill jig for drilling a frame having two inclined frame members, the jig comprising two inclined base portions, each adapted to be seated on a respective one of the inclined frame members, attachment means for releasably connecting the jig to the frame and guide means attached to a base portion adapted to guide a rotatable drill bit into the frame in a preferred direction, the guide means being movable relative to its associated base portion.

The drill jig in accordance with the present invention is particularly suitable for use in timber sections of comparatively small dimension, such as those found in window sashes. Moreover, the drill jig complements the use of existing drill jigs, which are used primarily for timber sections of larger dimensions, such as those found in window frames.

Also, the present invention may be used with the window sashes in situ, without the need to remove them from the frame.

Preferably, the jig comprises two elongate base portions, each base portion being adapted to lie along a respective one of the frame members.

In a preferred embodiment, the base portions are inclined substantially perpendicularly to one another, and preferably each base portion is provided with a respective guide means for drilling in a respective guide member.

Preferably, each guide means is movable parallel to the elongate axis of its respective base portion.

The means for releasably connecting the jig to the fram may comprise a clamp or vice, which is preferably attached to one of the base portions, which is adapted to clamp onto one of the frame members.

Preferably, the clamp or vice is pivotally mounted so that the jig may be used, for example, at all the corners of a window sash when in the open position.

By way of example only, a specific embodiment of the present invention will now be described, with reference to the accompanying drawing, which is a perspective view of an embodiment of drill jig in accordance with the present invention.

The drill jig comprises first and second elongate base portions 10,12 which are rigidly welded together, and a clamp 14 which is pivotally mounted on a pivot 16 at the free end of base portion 10, and by means of which the jig may be releasably attachable to a window sash 18 (which is held in the open position by means of a casement stay), illustrated schematically in dotted lines in the Figure. Each base portion 10,12 comprises a flat, elongate strip of rigid metal plate, such as mild steel, which is welded so that it lies perpendicularly to the other base portion 10,12. Each base portion is provided with a respective elongate aperture 20,22 whose longitudinal axis is aligned with the elongate axis of the respective base member.

A cuboidal metal block 24 is secured to the first base member 10 at the end where the base member 10 meets the second base. member 12. The block 24 is provided with a rectangular aperture 26 extending through the block 24, parallel to the longitudinal axis of the base member 10, and the lowermost edge of the aperture is level with the upper surface of the first base member 10 and the end of the second base member 12. An elongate bar 28 of rectangular crosssection is slidably disposed in the aperture 26, and is provided with a tubular drill guide 30 at one end, which is disposed above the elongate aperture 20 in the first base member 10. As illustrated, the tubular guide 30 is adapted to guide a rotatable drill bit 32 for drilling a longitudinal bore in the frame 18.The position of the tubular guide 30 is variable with reference to the first base member BO by means of a finber-operated threaded bolt 33 which is received in a corresponding threaded bore 35 in the block 24 and which can be rotated to bear upon thn upper surface of bar 28 to releasably fix it in a desired position with reference to the first base member tO. An alternative threaded bore 37, at right angles to the bore 35, passes through opposite faces of the block 24 and provides two alternative locations for the threaded bolt 33 which, when inserted in the bore 37, will bear upon the edge of the bar 28.This choice of three locations for the bolt 33 is useful since there may not always be sufficient space to be able to position the bolt in a particular bore, due to the proximity of the bolt to the window sash or pane.

A similar arrangement is provided on the second base member 12, with the exception that the block 24' is situated at the free end of the second base member 12, but otherwise the components are substantially identical to those associated with the first base member 10, and similar items have been given similar reference numerals, with the addition of a prime.

The clamp 14 which is used to releasably secure the jig to a window sash comprises a first plate 34 which is pivotally mounted on pivot pin 16 to be pivotable in a plane substantially parallel to the plane of the first base member 10. The clamp further comprises a jaw 36 in the form of a second plate parallel to the first plate 34, and which is slidably disposed on each of two elongate, parallel, cylindrical guide bars 38 depending downwardly from the first plate 34 substantially parallel to the second base member 12, the guide bars 38 passing through cylindrical apertures 40 in the jaw 36. The jaw 36 is movable relative to the first plate 34 by means of a rotatable threaded bolt 42 which is received in a correspondingly threaded bore 44 in the jaw 36.The bolt 42 is rotatable by means of a knurled head 46, and is held in position by the head 46 and a collar 48, which are disposed either side of the first plate 34.

The jaw 36 and the first and second base members 10,12 are provided with a thin layer of rubber 50,52 respectively, with appropriate cut-out portions corresponding to the elongate apertures 20,22. The rubber is to prevent bruising of the wooden frame 18, as will be explained.

In use, the jig is positioned on a corner of an open window sash with the sash held in position by the casement stay (not shown) and with the angle between the base portions 10,12 situated on the corner of the sash and with the base portions 10,12 extending parallel to the elongate axis of respective frame members. The pane of glass in a window frame is usually disposed towards one lateral edge of the frame, and depending on which edge the pane is secured, the clamp 14 is previously disposed to lie on the opposite side of the frame from the pane. The jaw 36 of the clamp is then adjusted by suitable rotation of the threaded bolt 42 to clamp one of the frame members between the jaw 36 and the undersurface of the first frame member 10.The jig is clamped tightly to the frame member, and consequently the rubber 50,52 helps to prevent bruising of the window frame, and reduces the damage to any paintwork which may be on the frame.

By slackening the bolts 33,33' and adjusting the position of the bars 28,28', the tubular guides 30,30' are disposed approximately above the centre of the frame member which extends parallel to the asis of that guide, and so that the drill will not contact any fasteners, e.g. star nails, which are used to secure the frame. For example, in the Figure the guide 30 which is associated with the horizontally-disposed base member 10 is adapted to be positioned above the centre of the vertically extending frame member of the frame 18, whereas the tubular guide 30' which is associated with the vertically extending base member 12 is adapted to be positioned above the centre of the horizontally disposed frame member of the frame 18.

When the tubular guides 30,30' are in position, the threaded bolts 33,33' are rotated to secure the bars 28,28' in position. Bores may then be drilled through the tubular guides into the respective frame members, and the bores usually extend just over half way along the respective frame members. It will be appreciated that the apertures 20,22 allow the drill bit 32 to extend through the associated base member 10,12 whatever the position of the tubular guides 30,30'.

When two bores have been drilled at one corner, each of the other corners is drilled in turn, and it is found that the alignment obtained is sufficiently good to enable the bores from adjacent corners to meet at the centre of the respective frame members, thereby producing a continuous bore around the frame 18, although it is not always desirable or necessary to produce such a continuous bore, since it is found that the preservative diffuses through the wood after a short while. The invention is particularly useful in the treatment of casement windows, since the frame need not be removed, and may be treated in situ.

Once the bores have been drilled, it is merely necessary to insert the preservative into the bores.

If the bores do not meet at the centre of each frame member, the one aperture at each corner is plugged with a threaded aluminium grub screw and the preservative is inserted via each of the other apertures, which are thereafter sealed with a further screw. If the bores do intersect and form one continuous channel, then all but one of the apertures are plugged and the preservative is inserted through the other aperture which is thereafter plugged.

The invention is not restricted to the details of the foregoing embodiment. For example, for very narrow frame members, it may not be possible to position the tubular guides 30,30' over the centre of the respective frame member, and in such circumstances it may be desirable to space one or more of the base members 10,12 away from the associated frame member.

This can be done either by placing a piece of spacing material of the desired thickness between the base member and the associated frame member, or may be achieved by providing one or more grub screws which can extend through each base member 10,12 or through a lug associated therewith, so that the base members 10,12 stand away from the frame members such that the tubular guides 30,30' may be positioned over the centre of the frame member to be drilled.

Also, although the invention is particularly suitable for treating members of relatively small cross-section it may equally well be used to treat members of larger cross-section. Moreover, it is not restricted to treating window sashes in situ, but may be used, for example, to treat other types of frame, such as window frames, either during construction or by first removing the frames.

Claims

CLAIMS.

1. A drill jig for drilling a frame having two inclined frame members, the jig comprising two inclined base portions, each adapted to be seated on a respective one of the inclined frame members, attachment means for releasably connecting the jig to the frame and guide means attached to a base portion adapted to guide a rotatable drill bit into the frame in a preferred direction, the guide means being movable relative to its associated base portion.

2. A drill jig as claimed in claim 1, comprising two elongate base portions, each base portion being adapted to lie along a respective one of the frame members.

3. A drill jig as claimed in claim 2, wherein the base portions are inclined substantially perpendicularly to one another.

4. A drill jig as claimed in any of the preceding claims, wherein each base portion is provided with a respective guide means for drilling in a respective guide member.

5. A drill jig as claimed in claim 2 or any of claims 3 or 4 when appendent to claim 2, wherein the or each guide means is movable parallel to the elongate axis of its respective base portion.

6. A drill jig as claimed in claim 5, wherein the or each guide means is attached to a respective adjustment member which is slidably disposed in an associated aperture in the jig and which is constrained to move parallel to the elongate axis of its associated base portion, there being means for releasably securing the or each adjustment member.

7. A drill jig as claimed in any of the preceding claims, wherein the or each guide means comprises a tubular guide which is adapted to guide a drill bit along the elongate axis of the guide.

8. A drill jig as claimed in any of the preceding claims, further comprising an aperture in a base portion, above which the guide means is disposed, to allow passage of a drill bit.

9. A drill jig as claimed in any of the preceding claims, wherein the means for releasably connecting the jig to the frame comprises a clamp or vice.

10. A drill jig as claimed in claim 9, wherein the clamp or vice is attached to one of the base portions, and which is adapted to clamp onto one of the frame members.

11. A drill jig as claimed in claim 10, wherein the clamp or vice is pivotally mounted on a base portion of the jig.

12. A drill jig as claimed in any of the preceding claims, wherein the drill jig is provided with resiliently deformable material, which, in use, abuts the frame in order to reduce or prevent bruising of the frame.

13. A drill jig substantially as herein described, with reference to, and as illustrated in the accompanying drawing.