GB2289013A

GB2289013A - Router clamping device

Info

Publication number: GB2289013A
Application number: GB9408608A
Authority: GB
Inventors: Michael Stirm
Original assignee: Black and Decker Inc
Current assignee: Black and Decker Inc
Priority date: 1994-04-29
Filing date: 1994-04-29
Publication date: 1995-11-08
Also published as: GB9408608D0

Abstract

A router slidably moveable along two parallel guide columns and clamping means for clamping the router to the columns at desired positions thereby, wherein said clamping means comprises a manually-operable screw adapted on operation to effect movement of one or more clamp elements perpendicular to the axis of said guide columns and into clamping relation with said guide columns. By means of the invention it is possible to effect accurate clamping of the router to both guide columns with a simple and rapid operation of a single manually-operated screw. <IMAGE>

Description

ROUTER CLAMPING DEVICE This invention relates to routers, and especially to improvements to the clamping mechanism employed in routers where it is desired to maintain the body of the router a fixed distance from the surface upon which the device is to be brought to bear.

Current router design provides for a housing which contains all the motor means necessary for driving the cutting bit of the device.

This housing is adjustably mounted upon two vertical guide columns and is capable of being moved slidably along these guide columns.

Integral with the housing there is provided clamping means actuated by means of a clamping screw or other similar device so that the housing and hence the bit may be accurately clamped in position for operation on a workpiece.

Traditional router designs provide either for the router to be clamped to one column only or for two identical sets of clamping means each disposed on opposite sides of the router housing so that individual adjustments may be made to the housing clamping position on each guide column. A problem has been identified with this traditional arrangement in that it is possible that the router base, and hence the cutting bit, will move out of plane parallel alignment with the workpiece. The misalignment of the base with the bit could cause inaccuracies in the routing operation. A further disadvantage is that the operator needs to use both hands in the clamping operation.

It is an object of this invention to provide means for clamping the housing to both guide columns by actuation of a single clamping device.

In accordance with the present invention there is provided a router having: a) abase; b) two parallel guide columns upstanding from said base; c) a housing slidable on said guide columns towards and away from said base; and d) clamp means to clamp said housing on said guide columns; wherein said clamp means comprises:: i) a rotatable screw threaded pin arranged in the housing transversely of said guide columns and parallel a line joining said columns, ii) a first clamp element adapted to abut a surface of one column in a first direction, iii) a second clamp element of the housing adapted to abut an opposing surface of said one column, iv) a third clamp element adapted to abut a surface of the other column in a second direction substantially opposing said first direction, v) a fourth clamp element of the housing adapted to abut an opposing surface of said other column, wherein said pin is threaded in said first clamp element and wherein said third clamp element is one end of said pin.

The first clamp element may be in the fonn of a saddle attached to the router and surrounding the guide columns, operation of the screw clamping said one guide column between the first clamp element and a second clamp element and the other guide column between said fourth clamp element and the screw.

The first and third clamp elements may both be slidably movable along guide paths in the housing in said first and second directions, operation of the screw causing said first and third clamp elements to move in opposite directions to clamp respective guide columns to said surfaces of the housing.

In one embodimen: of the present invention there is provided a router clamping device characterised by a housing having disposed therein a motor, guide columns and a clamping element, said housing supporting said clamping element; said clamping element extruding from either side of the housing and having disposed therein an aperture through which the guide columns extend; said clamping element additionally possessing engagement means and screw clamping means, said screw clamping means being in screwable engagement with the clamping element and acting upon one of the guide columns; so that when said screw clamping means is actuated, said screw clamping means acts upon one of the guide columns whilst additionally drawing the clamping element from the housing so that the engagement means acts upon the other guide column thereby holding the router housing in secure engagement with the guide columns.

In a second embodiment, the clamping element may consist of two substantially rectangular blocks relatively precisely guided within corresponding guide paths in the housing, said rectangular blocks having the corner nearest their respective guide column bevelled; said screw clamping means being in screwable engagement with one of the rectangular blocks and acting upon the other rectangular block; so that when the screw clamping means is actuated, one of the blocks is drawn towards one of the guide columns whilst the other rectangular block is pushed towards the other guide column in order that these blocks may engage said guide columns thereby holding the router housing in secure engagement with the guide columns.

The invention will now be described further with reference to the accompanying diagratrimatic drawings in which: Figure 1 is an aerial cross-sectional view through the router housing guide columns and clamp element in a first embodiment.

Figure 2 is an alternative clamping arrangement to that of Figure 1; and Figure 3 is a cross-sectional aerial view through a second embodiment of the invention showing the router housing, clamping device and guide columns.

In the embodiment of Figure 1, a first clamping element in the fonn of a saddle 1 encloses both guide columns 2 and carries a clamping screw 5,6 at one end. The first clamping element 1 is arranged within the motor housing 4 and is closely guided by surfaces thereof for movement in the axial direction of the clamping screw 5,6. The housing 4 provides second and fourth clamping elements 3 engaging in normally sliding contact with inner surfaces of the guide columns 2. A third clamp element is provided by the end of screw 6. To clamp the housing 4 in a pre-determined position, the clamping screw 5,6 is rotated so that the end of the screw comes into engagement with the outer surface of one guide column 2 and thereby the opposite end of the clamping element 1 is pulled into engagement with the outer surface of the other guide column 2.Thereby the clamping element 1 is held in a defined position with respect to the guide columns 2 and holds the housing 4 and therefore the router bit (not shown) in such a position.

The embodiment of Figure 2 differs from that of Figure 1 in the position of the engagement surface 17 of the first clamping element 1 and the adjacent guide column 2. The engagement surface 17 has been rotated through a pre-detennined angle 11 about the guide column 2 so that lateral tolerance problems as to the position of the guide column 2 with respect to the supporting portion 13 of the housing 4 are avoided.

In the embodiment of Figure 3, two separate clamping elements in the form of sliding blocks 27,28 are provided, each of which is guided within a corresponding guide path formed in the housing 24.

The clamping screw 25,26 is screwed into one 27 of the clamping elements and engages an end surface of the other 28 of the clamping elements. Rotation of the clamping screw 25,26 pushes the clamping element 28 into clamping arrangement with one of the guide columns 22 and pulls the other clamping element 27 into clamping arrangement with the guide column 22. This results in a clamped position of the housing 24 with respect to the guide columns 22.

In this embodiment, the clamping element 27 constitutes said first clamping element and the housing provides surfaces 23 constituting the second and clamping element. However, in this case, the third clamping element is likewise formed by the end of the screw 26 but acting through the agency of block 28 on the other of the guide columns.

By means of the invention it is possible to effect accurate clamping of the router to both guide columns with a simple and rapid operation of a single manually-operated screw.

It will be understood of course that the above embodiments are described purely by way of example and modifications can be made within the scope of the claims.

Claims

1. A router slidably moveable along two parallel guide columns and clamping means for clamping the router to the columns at desired positions thereby, wherein said clamping means comprises a manually-operable screw adapted on operation to effect movement of one or more clamp elements perpendicular to the axis of said guide columns and into clamping relation with said guide columns.

2. A router according to claim 1 wherein a clamp element is in the form of a saddle attached to the router and surrounding the guide columns, operation of the screw clamping one guide column between the clamp element and a surface of the router and the other guide column between another surface of the router and the screw.

3. A router according to claim 1 wherein two clamp elements are slidably movable along guide paths in the router, operation of the screw causing said clamp elements to move in opposite directions to clamp respective guide columns to surfaces of the router.

4. A router having: a) abase; b) two parallel guide columns upstanding from said base; c) a housing slidable on said guide columns towards and away from said base; and d) clamp means to clamp said housing on said guide columns; wherein said clamp means comprises: i) a rotatable screw threaded pin arranged in the housing transversely of said guide columns and parallel a line joining said columns, ii) a first clamp element adapted to abut a surface of one column in a first direction, iii) a second clamp element of the housing adapted to abut an opposing surface of said one column, iv) a third clamp element adapted to abut a surface of the other column in a second direction substantially opposing said first direction, v) a fourth clamp element of the housing adapted to abut an opposing surface of said other column, wherein said pin is threaded in said first clamp element and wherein said third clamp element is one end of said pin.