GB2321420A

GB2321420A - Clamping rail with positioning system for portable power tools

Info

Publication number: GB2321420A
Application number: GB9800722A
Authority: GB
Inventors: George Lupton
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-01-23
Filing date: 1998-01-15
Publication date: 1998-07-29
Anticipated expiration: 2018-01-15
Also published as: GB9800722D0; GB9701405D0; GB2321420B

Abstract

The apparatus comprises a first rail member 11 having a second rail member 10 attached thereto which runs in a channel member 1 to enable raising and lowering of said first rail against a worktable such that various forms and sizes of workpiece can be releasably held between the first rail underside and the worktable surface. Two or more sets of guide channels on the first rail member independently enable one or more clamping bars 21 to clamp the workpiece in the horizontal plane relative to a reference plate 4, also one or more independent carriages 14 can be guided rectilinearly or can be fixed in position above the workpiece. Mechanisms attached to said carriages allow control of portable power driven tools of the hand held type, to perform working operations upon the workpiece.

Description

CLAMPING RAIL WITH POSITIONING SYSTEM FOR PORTABLE POWER TOOLS Description of Invention The invention relates to the holding of a workpiece onto a worktable or workbench and to the working of the workpiece (including drilling and sawing) by means of the controlled application of portable power driven tools of the hand held type.

It is well known that considerable skill is required on the part of toe user to achieve a precisely located drilled hole of a precisely known depth and at a precise angle (usually perpendicular) to the surface of a material, when manually holding and controlling a pistol grip type power driven hand drill.

Several designs of drill stand for such handdrills are commercially available to assist the accurate drilling of holes vertically in small items. Whilst such drill stands offer a good range of vertical movemen tttere is usually no provision for drilling in any other direction The distance of a hole relative to the edge of the workpiece is limited in the horizontal plane by the distance between drill bit and support pillar of the stand and thus rests the size of workpiece items that can be held to be drilled.

The accurate location and drilling of holes in large items is usually accomplished by a machine tool system (sometimes known as a machine centre) involving either a power driven drill head in conjunction with a movable worktable for moving the workpiece or a guide system to enable a power driven drill head to be moved over a fixed workpiece. The major differences between a machine centre and a drill stand are that the former is relatively expensive, has means for holding both workpiece and power tool, is free standing, and also has means for independently positioning both workpiece and tool whereas the latter is bench mounted and can hold and position the power tool only.

In addition it is well known that considerable skill is required on the part of the user to achieve a precisely located straight cut in block, plank or sheet materials when manually holding and controlling a hand held power driven circular saw.

Such saws usually incorporate a rip fence guide, to position the cut relative to the edge of the workpiece. However the edge of the workpiece must be a straight edge and the distance between edge and cut is limited to the bar length of the rip fence guide, usually about 20 cm.

Several designs of saw bench tables are commercially available to assist the accurate cutting of materials by sawing, wherein the portable circular saw is held in fixed position, supported in inverted form in a table surface, said table incorporating guides to assist the user to manually transport the workpiece at a desired position and attitude to the saw blade.

Existing accessories for hand held power driven tools, either bench mounted or free standing, usually have no provision for the holding of large or tubular or irregular shaped workpieces to the workbench and usually do not have means for more than one type of working operation (e.g. drilling plus sawing or routing) to be applied to the workpiece.

According to the present invention there is provided an apparatus comprising a first rail member having a second rail member attached at an extremity perpendicularly to an undersurface of the first rail member, said second rail member being caused to move in a vertical channel member to enable raising and lowering of said first rail member against a worktable such that various forms and sizes of workpiece can be releasably held between the first rail member underside and the worktable surface. Two or more sets of guide channels on the first rail member enable one or more independently sliding clamping bars to releasably secure the workpiece in a substantially horizontal plane relative to a reference plate. Also one or more independent sliding carriages can be guided rectilinearly along the first rail member or can be fixed in position on the first rail member relative to the reference plate.

Mechanisms attached to said carriages allow control of movement of attached power-driven tools of the hand held type, such that more than one type of said normally hand held tools can be used with precision to enable more than one working operation upon the workpiece.

The apparatus is an arrangement of mechanical parts. The parts may be named for convenience tF'a reference plate' the cha block' lithe odafir rail:, me guided carriage ffle guided clamp bar', the saw holder and withe drill holder'.

A preferred embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which Figure 1 shows in perspective a general arrangement of parts for the purpose of working of a workpiece by drilling Figure 2 shows in section a preferred form of the guidance rail with guided carriage Figure 3 shows in section a preferred embodiment of the guided damp bar Figure 4 shows in section a preferred embodiment of the saw holder Figure 5 shows in perspective a preferred embodiment of the drill holder Figure 6 shows in section a preferred embodiment of the drill holder Figure 7 shows in perspective an arrangement of assemblies for cross cutting Figure 8 shows in perspective an arrangement of assemblies for length cutting In the following description it is assumed that the surface of the worktable is substantially horizontal, the words vertical and horizontal are used to mean perpendicular to and parallel with the worktop surface respectively.

Referring to Figure 1: The channel block, 1 has means for releasably fixing to the support member of a worktop of a worktable (or workbench), adjacent the edge of the worktop, said fixing means preferably being by two angle members 2 which are fixed to the support member. Said angle members preferably have slots for engagement with adjustable protrusions 3 on said channel block 1.

The channel block 1 provides a channel which is mixed such that the central axis of said channel is perpendicular to the plane of the surface of the worktop. A reference plate 4 is fixed to be adjacent the edge of the worktop Distance pieces 5 in the channel are shaped to allow vertical movement of the guidance rail vertical member 10 without lateral play or twist. Said channel block 1 additionally provides means for raising the guidance rail vertical member 10 perpendicular to the worktable surface. A preferred embodiment of said raising means is by jack screw 6, engaging in tapped parts 7 fixed within said guidance rail vertical member 10 and tapped parts 8 fixed at the base of the channel block 1. . The channel block 1 has securing means, said securing means preferably being by a hand operated screw damp 9 acting on the guidance rail vertical member 10 to releasably secure said vertical member 10 from further movement. Operation of said jack screw 6 and clamp screw 9 releasably secure the guidance rail horizontal member 11 at a desired height relative to the worktable surface or to act as a clamp to retain the workpiece between the undersurface of said member 11 and the surface of the worktable The guidance rail vertical member 10 and a horizontal member 11 are securely fixed together at precisely 90 ". The junction occurs about 4 of the way along the horizontal member.

The guidance rail horizontal member 11 carries a scale 12 along its length.

The guidance rail horizontal member 11 has guide means for allowing one or more guided carriages 14 to move rectilinearly along the length of said member with minimal lateral play or twist.

Additionally said member 11 has further guide means for allowing one or more guided clamping bars 21 to move rectilinearly along the length of said member 11 independently of said guided carriages 14.

Several configurations of guide arrangement and guide profile are possible, however it is an essential feature of this invention that, howsoever realised and whether embodying rotational parts or not, the guide system allows two or more guided carriages to move independently of each other and without conflict, over the length of the guidance rail horizontal member 11.

Another essential feature of this invention is that said member 11 is of sufficient rigidity to resist torsional forces without any appreciable torsional deformation.

Referring to Figure 2: A preferred embodiment of the guidance rail horizontal member 11 is shown, wherein two guide channels 13 on each side of said member 11 run along the length of each side. The channels are preferably symmetrical about the centre-lines of said member 11. The channels are preferably separated by sufficient distance to allow means for clamping or adjusting the position of sliding parts, to be employed.

The upper channels 13a allow suitably shaped guided carriages 14 and the bottom channels 13b allow suitably shaped guided clamping bars 21 each having means of engagement 19 with their respective said guide channels, to slide along the length of said guidance rail 11. The means of engagement 19 preferably being of a material having a low friction and of suitable profile to engage in said guide channels to produce minimal lateral movement of the guided carriage 14.

The top plate of the guided carrier 14 canies one or more securing means 18, a preferred securing means being a screw, to secure said carrier 14 in position on said guidance rail 11.

The guided carriage 14 additionally embodies means for attachment of additional parts (including but not limited to, a saw holder, a drill holder ) preferred attachment means being One or mO5e ulreaueu Il illyS 15, 17.

The guided carriage 14 additionally embodies engagement parts to enable the sliding movement of said carriage along said guidance rail said engagement parts 19 preferably being of material having a low friction and of suitable profile to engage in said guide channels.

Referring to Figure 3: The guided clamping bar upper member 21 has means of engagement 19 which engage with and slide freely in said guides 13b as aforesaid and additionally has securing means, preferable securing means being threaded fixing 22 with lever bar 23 for the securing of said clamping bar upper member 21 at a desired position along said guidance rail 11.

The guided damping bar upper member 21 has a scale plate 24. Said upper member additionally carries a lower member 25. Said lower member 25 can rotate about pivot 26 and can be releasably clamped, preferably by means of screw 27, to be either perpendicular to, or at an angle to, the length axis of the guidance rail horizontal member 11 . The scale plate 24 has an angular scale to indicate the angle being selected. Said lower member 25 passes under said guidance rail 11. The workpiece can thus be held under said guidance rail 11 perpendicular thereto or at any desired angle thereto or to the reference plate 4, using one or two such clamping bar assemblies.

The lower member 25 Is jointed, a preferable jointing means being a hinge 28, to allow the free end 29 of said lower member to swivel in a vertical plane. This is to ensure that it is possible to have either the whole of or at least a portion of, the side of said free end 29 to be in contact with and thus hold a rectangular or tubular or irregular shaped workpiece.

Referring to Figure 4: The saw holder consists of a right angled bracket assembly comprising a link bracket 36 which can be attached to the guided carriage 14 by attachment means co-operable with the attachment means 15 of the guided carriage 14.

Right angled bracket 30 has provision to restrain the rectangular base plate of the circular saw (shown in dotted lines) from vertical and horizontal movement relative to said right angled bracket. A preferred means of restraint being by hinged U section arms 31,32 , each U section arm being on one of the two mutually perpendicular sections of said right angled bracket. Each of the two mutually perpendicular sections of said right angled bracket provides clamping means to secure said U section arms in damping position, said clamping means preferably being by clamp screws 33,34 .

It will be appreciated by reference to figures 7 and 8 that it is possible to position and retain the rectangular baseplate of the circular saw in either of two attitudes thus allowing the cutting blade of a range of sizes of circular saw to be positioned parallel to or perpendicular to the length axis of the guidance rail 11.

One or more means of adjustment 35 are provided on said link bracket 36 to provide an adjustable distance piece between said bracket and said guidance rail to position the angle of the cutting blade when in its 0 reference attitude to be perpendicular to the worktable surface.

Referring to figures 5 and 6 and t: The drill holder assembly comprises of a channel member 40, a mounting plate 60, means for adjusting the position of said channel member relative to said mounting plate, a hand-drill carrier 50, means for moving said hand-drill carrier within said channel member, guide means for guiding the movement of said hand drill carrier within the channel member, and catchment means 43 for arresting the movement of said hand drill carrier Additionally said hand drill carrier 50 has means for releasably securing a range of sizes of pistol grip type hand-held power driven drills thereto.

Preferably the sides of said hand drill canier each have one or more guide channels 51 - 54 along the length of each side. The sides 41,42 of said channel member 40 have engagement parts 19 preferably of material having a low friction and of suitable profile to engage in said guide channels 51,52 to enable the sliding movement of said carriage within said channel member to be rectilinear.

Means for moving said hand-drill carrier within the channel member preferably employ a rack part 55 attached to the hand drill carrier by means of securing brackets 56 and a pinion 44 attached in position on the channel member 40 to engage co-operably with the rack part 55 to effect means of moving the hand drill carrier closer to or further from the worktable surface, to effect a drilling operation. One or more handle parts 45 attached to the pinion via connector 46 provide means of manually rotating said pinion.

Said hand drill carriage has means for releasably holding a pistol grip type hand drill Said holding means preferably comprises a lower clamp 57 to clamp around the circular part of the power drill, the collar, situate directly behind the chuck. Said lower clamp 57 is preferably a split hexagonal ring type clamp to accommodate a range of drill collar szes. Preferably the is additionally an upper clamp 58 to damp around the rear part of the body of the hand-drill in the region of the hand-drill armature rear bearing. Means of engagement and fixing 59 co-operable with said guide channels 53,54 of the hand drill carrier are provided on the upper clamp 58 for moving the position of said upper clamp, to accommodate a range of drill lengths.

.A pointer 48 fixed to said hand drill carrier indicates, on a scale 47 on said channel member 40, relative movement of said hand drill carrier and said channel member.

The position of the drill bit can be adjusted in the horizontal plane to a desired position above the worksurface by means of adjustment provided on the mounting plate 60 and channel member 40 co-operably. Preferable means of adjustment are by jack screw 61 and guide bars 62,63 attached to the mounting plate said jack screw and said guide bars passing through tapped and clearance holes in the channel member support block 49 Referring to Figures 7 and 8-Sawing The saw holder angle bracket 30 when attached to the guided carriage 14 via link bracket 36 allows any size of circular saw to be securely clamped, by its baseplate, relative to the guidance rail 11. The saw is held in its normal working attitude, blade down, with its safety guard system fully operable.

In the arrangement of Figure 7 the saw base plate can be clamped as aforesaid to said angle bracket to allow a running cut, parallel to the guidance rail. The workpiece is held by one clamping bar 21 against the reference plate 4.

In the arrangement of Figure 8 the circular saw can be fixed to the angle bracket 30 as aforesaid such that its saw blade is perpendicular to the length axis of the guidance rail horizontal member 11. The guided carrier 14 is moved along the guidance rail horizontal member 11 and then fixed in position relative to the reference plate 4 by fixing means 18 using the scale 12 on the guidance rail 11 as a position indicator. The guidance rail 11 is positioned to give a slight vertical clearance using the jack screw 6 in conjunction with screw clamp 9. The guided clamping bars 21 are fixed in position to act as parallel guides to allow for planks, tubes or sheet materials to be pushed under the guidance rail to the saw blade.

Claims

What is claimed is 1. An apparatus for releasably clamping a workpiece to a worksurface said apparatus also providing means for guiding and positioning devices for working upon the workpiece, said apparatus comprising a first rail member, one or more carriages constrained to move co-operably with said first rail member, a second rail member attached at an extremity to the undersurface of said first rail member, a channel member with axis of channel in plane perpendicular to and adjacent the edge of the worksurface, said second rail member being constrained to move within and be releasably fixed in position within said channel member, to enable raising and lowering of said first rail member against a worktable such that various forms and sizes of workpiece can be releasably held between the first rail member underside and the worktable surface, one or more third rail members constrained to move co-operably with said first rail member to clamp the workpiece in the horizontal plane.
2. A workpiece clamping apparatus as claimed in claim 1 wherein means are provided on the channel member for the attachment of said channel member to be below, perpendicular to the plane of and adjacent the edge of, the worksurface.
3. A workpiece clamping apparatus as claimed in claim I or claim 2 wherein means are provided on the channel member co-operable with the second rail member to effect the movement of said second rail member within said channel member.
4. A workpiece clamping apparatus as claimed in claim 3 wherein guide means are provided on the channel member co-operable with the second rail member to constrain the movement of said second rail member within said channel member to be rectilinear.
5. A workpiece clamping apparatus as claimed in any preceding claim wherein catchment means are provided on the channel member co-operable with the second rail member for arresting the movement of said second rail member thus to define the limits of rectilinear movement of said second rail member within said channel member
6. A workpiece clamping apparatus as claimed in any preceding claim wherein means are provided on the channel member for releaseably securing the position of the second rail member at a desired position relative to said channel member.
7. A workpiece clamping apparatus as claimed in any preceding claim wherein guide means are provided on the first rail member co-operable with one or more carriages to constrain the movement of said carriages along said first rail member to be rectilinear.
8. A workpiece clamping apparatus as claimed in claim 7 wherein said guide means are provided on the first rail member to enable each of two carriages to move independently and unconflictingly of each other over the length of said first rail member.
9. A workpiece clamping apparatus as claimed in claim 8 wherein means are provided on each carriage for releasably securing said carriages each in desired position on the first rail member.
10. A workpiece clamping apparatus as claimed in claim 8 wherein means of attachment are provided on the carriages for releasably attaching further devices to said carriages.
11. A workpiece clamping apparatus as claimed in claim 10 wherein said devices are of a design suitable for holding tools for the working of the workpiece.
12. A workpiece damping apparatus as claimed in claim 10 wherein said devices are of a design suitable for holding a third rail member below and perpendicular to or at an angle to the first rail member.
13. A workpiece clamping apparatus as claimed in claim 11 wherein a device suitable for retaining a pistol grip type power driven hand drill has means of adjustment of position of said drill in two directions perpendicular to the plane of said first rail member.
14. A workpiece clamping apparatus as claimed in claim 11 wherein a device suitable for retaining a portable power driven circular saw has means of retention of said circular saw in two attitudes with the plane of the saw blade parallel or perpendicular to the plane of said first rail member.
15. A workpiece clamping apparatus substantially as hereinbefore described with reference to the accompanying drawings.