GB2311241A - Attachment for a woodworking lathe - Google Patents

Abstract

An attachment for a woodworking lathe has two first parallel guides 18 on each of which a traveller 20 is slidably mounted. One or two second guides 22 is/are fixedly mounted between said travellers. A slider 24 for receiving a tool holder 26 is slidably mounted on or between the second guide or guide(s). The first guides are mounted operatively on the bed of the lathe. A rotary tool may be employed and the tool may be mounted on a pivotal arm. A workpiece holder on the lathe may comprise two opposed clamp members mounted for rotation with provision to hold a workpiece spaced away from the rotational axis. The lathe may carry an indexing device comprising a plate with recesses or holes spaced equally about a coaxial circle. Such holes or recesses are engageable by a detent.

Description

ATTACHMENTS FOR A WOODWORKING LATHE This invention relates to attachments for a woodworking lathe.

In accordance with a first aspect of the invention, there is provided an attachment for a woodworking lathe, comprising: two first parallel guides on each of which a traveller is slidably mounted; one or two second guides fixedly mounted between said travellers; a slider for receiving a tool holder slidably mounted on or between the second guide or guide(s); and means for mounting the first guides operatively on the bed of the lathe.

The attachment allows the tool to be moved both along the bed and across the bed of the lathe. Thus decorative work can be carried out both between centres and on the faceplate. Taper turning and tapered fluting can be carried out simply by adjusting the first guide(s) to the angle required to give the desired taper.

The tool holder may comprise a post and means to clamp a tool thereto or a collar for receiving the body of a rotary tool.

Preferably, a stylus is mounted on said slider and means is provided for securing a template in a position in which it can be followed by the stylus. Articles with identical profiles can then be produced.

In accordance with a second aspect of the invention there is alternatively or additionally provided an attachment for a woodworking lathe, comprising: a base member adapted for mounting operatively on the bed of the lathe; an arm mounted on the base for pivotal movement about one axis; and a tool holder mounted on the arm for pivotal movement therewith and spaced by a radius from the axis.

Provided the pivotal axis of the arm intersects the axis of the lathe, the tool is guided by the arm to turn a sphere from the work piece.

In accordance with a third aspect of the invention there is additionally or alternatively provided an attachment for a woodworking lathe, comprising: a clamp adapted for rotation about a first axis on the lathe, the clamp having two opposed clamp members provided with means defining a plurality of positions for clamping respective workpieces between the clamping members, said workpieces being adjustable about respective second axes parallel to and equally radially spaced from the first axis.

In use the workpieces are clamped between the clamping members producing a cage. The cage is turned generally by hand on a centre lathe and a rotating tool e.g.

a router is applied to the workpieces to machine what will be one face of a multi faceted article. The clamp is loosened, the workpieces adjusted to present another face for machining and the process repeated until all faces have been completed. The attachment is best used with a profile attachment embodying the first aspect in order to ensure that all faces are the same.

In accordance with a fourth aspect of the invention, there is provided an attachment for a woodworking lathe, comprising: a plate having a hole to receive the spindle of the lathe to be clamped thereto by a chuck, faceplate or thread protector, said plate having a plurality of recesses or holes therein equally spaced around a circle centred on the axis of the spindle; and a spring loaded detent for mounting on the bed of the lathe so as to engage in the recesses or holes.

The workpiece can thus be indexed accurately to perform such operations as cross boring, fluting and so on.

Embodiments of the different aspects of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a pictorial view of a profiler attachment for a woodworking lathe embodying the first aspect of the invention with one form of tool holder; Figure 2 is a pictorial view of the attachment of Figure 1 when fitted to a lathe and with an alternative tool holder; Figure 3 is detail of the attachment of Figures 1 and 2 with an alternative tool holder; Figure 4 is a detail similar to that of Figure 3 showing another tool; Figure 5 is a pictorial view of a sphere turning attachment for a woodworking lathe embodying the second aspect of the invention; Figure 6 is an exploded pictorial detail of the attachment of Figure 5, but alternatively mounted on the bed of the lathe; Figure 7a is an exploded pictorial view of an attachment for turning multiple work pieces and embodying the third aspect of the invention; Figure 7b is a pictorial view of a workpiece for the embodiment of Figure 7a; Figure 7c is a detail showing how the workpieces are indexed in the embodiment of Figure 7a; Figure 8 is a pictorial view of an indexing attachment for a woodworking lathe embodying the fourth aspect of the invention; and Figure 9 is a detail of the detent of the indexer of Figure 8.

Referring to the drawings, a profiler attachment 2 is bolted to the bed 4 of a lathe 6. To this end two parallel bed bars 8 receive bolts 10. The bed bars 8 lay across the bed 4 of the lathe and clamps 12 are tightened up on the underside of the bed by means of the bolts 10.

The bed bars 8 support spaced end blocks 16 between which guide bars 18 are fixedly mounted. A traveller 20 is mounted on each guide bar 18 for sliding movement therealong. The travellers 20 are joined by one or two guides, in the example illustrated by two guide bars 22. In an alternative, not shown, a single rectangular guide bar could be provided. A slider 24 is mounted between the guide bars 22 for sliding movement therealong. The slider supports a tool holder. In the example illustrated in Figure 1 the tool holder is a post 26 having a cross bore 28 in which a set screw 30 secures a fixed cutting tool 32.

A stylus 35 is mounted on the slider, extending generally normal to the length of the guide bars 22. The stylus 35 has a pointed tip 36 intended to engage a profile 38 of a template 40. the template is mounted by machine screws 17 on the end blocks 16.

In use the tool is steadied by the arrangements of guides and can be moved in any direction in a plane set by the height of the post 26. The arrangement is useful for what would traditionally have been turned with a hand tool on a conventional tool rest. The cut can be limited by stops 34 on the bars 18 and 22. The arrangement is of even more value, however, when used with the stylus and template, the tool being then moved so that the cut is limited by the engagement of the stylus with the template so that articles can be turned all with the same profile. Use of the apparatus does not preclude use of a conventional tool rest which can, if desired, be fitted to the slider 24.

In the arrangement illustrated in Figure 2 a router 50 is secured to the post 26 by means of a collar 52.

Figures 3 and 4 show alternative routers 54 and 56 secured to the slider 24 by means of a collar 58 or 60, adapted to receive a 43 or 60 mm Euro type collar of the tool.

All the tools mounted into the post 26 or collar 52, 58 or 60, fitted to the slider 24, can be positioned and fixed at a variety of angles to enable different cuts to be made in the workpiece. Both axes can be stopped at any point to allow precise lengths for fluting etc.

The attachment clamps to the bed of most twin, round or square bed lathes. It enables production of many designs that can be produced on an ornamental turning lathe.

Various tools such as a router, drill, or mini drill may be used. The slider is able to move either along the bed (Y axis) or across the bed (X axis). Thus, decorative work can be carried out both between centres and on the faceplate.

Whilst normally used mounted between the headstock and the tailstock, it can also be used clamped either side of a headstock which swivels, as shown in Figure 2, to allow for larger bowl decoration.

Taper turning and tapered fluting can be carried out simply by adjusting the bed bars to any angle to give the required taper.

In the arrangement shown in figure 5, the tool holder collar is not mounted directly on the slider 26 but at the end of an arm 62. The arm is pivotally mounted on the slider by means of a bolt 64 so as to be pivotable about a single axis. When this axis intersects the axis of the lathe, pivotal movement of the arm will constrain movement of the tool to cut a sphere in the workpiece 66 as illustrated In an alternative arrangement shown in Figure 6, the arm 62 is mounted on the bed 4 of a lathe by a clamp comprising clamp members 70 and a bolt 72 which is received by a threaded hole in the lower clamp member. A wooden spacer may be required to suit the lathe to ensure that the unit is on the centreline of the lathe.

Various sized spheres may be produced placing the set screw 64 into the required one of a plurality of holes 74 (see Figure 6) approximating to the diameter of ball required. The position of the cutter may be adjusted to the precise diameter required. The post 26 is secured in a hole 76 by a grubscrew 78.

In use, a piece of timber is placed between centres and rough turned to the desired diameter using the standard toolrest. Pencil marks are placed on both sides of the centre point of the sphere, equal to the diameter required.

These marks should allow sufficient space for the cutting tool to pivot far enough so as to cut as much wood as possible before the sphere is parted-off. These areas are now relieved to a minimum, allowing for safe working. The tool rest is removed and the Sphere-maker assembled on the bed. The centrepoint of the cutting tool is lined up with the centre of the proposed sphere (i.e. centred between the pencil marks). With lathe running, the pivot bar is swung from right to left the cutter will start to produce a spherical area. A router can be used more effectively, using a mounting adaptor. A second hole 80 is used for mounting the router.

A plurality of identical articles may be made using the attachment of Figure 7. The workpieces are prepared by turning as illustrated in Figure 7b so that each has a shoulder 80 at both ends. The stub 82 projecting from each shoulder has a diameter to fit a respective one of twelve holes 84 in one of two clamp members 86. Each clamp member has a square central hole 88 to receive a square section drive shaft 90. At each end the shaft 90 has a screw threaded extension 91 to receive a cylindrical nut 92 and a hexagonal nut 94 by which the clamping members 86 are tightened on the workpieces. Pencil marks 96 (see Figure 7c) on an end of the workpieces are used to index the position of the workpieces in the clamp.

In use the unit is mounted between centres with the nut 92 in a chuck and the other end supported by a revolving centre (not shown).

The attachment will produce any number (up to twelve off) of the same article, such as chess pieces, knife, fork and spoon handles, napkin rings etc., all with a varied number of sides and sectional profiles. e.g. three corner, square, semi oval hexagon etc.

The first face of all the pieces is turned until it is complete. The unit is then removed, loosened and all woods are moved round to the next index point and the unit is re-clamped. The second face is then turned and so on until all faces are complete.

The unit is intended to be used with the profile attachment illustrated in Figure 1 so that a router can be used preferably with a template. It can also be indexed using the attachment to be described next. This unit should be rotated manually: not under power.

Referring to Figures 8 and 9, an index plate 100 mounted on the lathe spindle 102 (spindle register) and clamped by either a chuck, faceplate or thread protector.

There are two rings of indexing holes or recesses 104 one containing 45 equally spaced holes the other containing 48 equally spaced holes. That will cover most applications, but any combination of holes can be included in one disc to give a larger range of indexing positions.

In an alternative arrangement (not illustrated) the holes or recesses are provided in the edge of the disc 100.

A base plate 106 of the indexer is clamped to the bed 4 of the lathe by a clamp plate under the bed which has a threaded hole therein. A bolt 108 is placed through the base plate, and fastened to the clamp plate. A square post 110 is located at one end of the base plate. The base plate is stepped (see Figure 9) to locate the spindle in alternative positions at right angles. That facilitates use both when turning between centres and with the headstock swivelled as in Figure 2.

A spring loaded ball detent is located in an end of a screw 114. The screw is mounted in a threaded hole in the post 110. the clamp and the screw are adjusted so that the detent engages one or other series of holes 104.

Claims (20)

1. An attachment for a woodworking lathe, comprising: two first parallel guides on each of which a traveller is slidably mounted; one or two second guides fixedly mounted between said travellers; a slider for receiving a tool holder slidably mounted on or between the second guide or guide(s); and means for mounting the first guides operatively on the bed of the lathe.

2. An attachment as claimed in claim 1, wherein the mounting means comprises two clamps, one supporting each first guide at its ends.

3. An attachment as claimed in claim 1 or 2, wherein the tool holder comprises a post and means to clamp a tool thereto.

4. An attachment as claimed in any preceding claim, wherein the tool holder includes a collar for receiving the body of a rotary tool.

5. An attachment as claimed in any preceding claim, including a stylus mounted on said slider and means for securing a template in a position in which it can be followed by the stylus.

6. An attachment for a woodworking lathe, comprising: a base member adapted for mounting operatively on the bed of the lathe; an arm mounted on the base for pivotal movement about one axis; and a tool holder mounted on the arm for pivotal movement therewith and spaced by a radius from the axis.

7. An attachment as claimed in claim 6, wherein the radius is adjustable.

8. An attachment as claimed in claim 6 or 7, in combination with an attachment as claimed in any of claims 1 to 4, and wherein the slider constitutes the base member.

9. An attachment for a woodworking lathe, comprising: a clamp adapted for rotation about a first axis on the lathe, the clamp having two opposed clamp members provided with means defining a plurality of positions for clamping respective workpieces between the clamping members, said workpieces being adjustable about respective second axes parallel to and equally radially spaced from the first axis.

10. An attachment as claimed in claim 9, including a cylindrical projection to be received by a chuck on the lathe.

11. An attachment as claimed in claim 10 or 11, wherein the means defining the plurality of positions comprises a plurality of holes in each clamp member, said holes having centres equally radially spaced from the first axis.

12. An attachment as claimed in any of claims 9 to 11, in combination with an attachment as claimed in any of claims 1 to 7.

13. An attachment for a woodworking lathe, comprising: a plate having a hole to receive the spindle of the lathe to be clamped thereto by a chuck, faceplate or thread protector, said plate having a plurality of recesses or holes therein equally spaced around a circle centred on the axis of the spindle; and a detent for mounting on the bed of the lathe so as to engage in the recesses or holes.

14. An attachment as claimed in claim 13, wherein the detent is spring loaded.

15. An attachment as claimed in claim 13 or 14, wherein the recesses or holes are in a face of the plate.

16. An attachment as claimed in claim 13 or 14, wherein the recesses or holes are in an edge of the plate.

17. An attachment as claimed in any of claims 13 to 16, including two sets of recesses or holes at different pitches.

18. An attachment as claimed in claim 17, including one set of 48 recesses or holes and one set of 45 recesses or holes.

19. An attachment as claimed in any of claims 13 to 18, in combination with an attachment as claimed in any of claims 1 to 12.

20. An attachment as claimed in any preceding claim in combination with a woodworking lathe.