AU660114B2 - Jaw assembly - Google Patents

Description

P/00/011 Regulation 3.2 660114

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT 0.0.0 00 Name of Applicant: Actual Inventor: Address for Service: VICTOR VERRECCHIA Victor Verrecchia TREVOR DREDGE ASSOCIATES Patent Trade Mark Attorneys 13th Floor, 379 Queen Street BRISBANE, QLD, 4000 GPO Box 1339, BRISBANE, 4001 "Jaw Assembly" e**o Invention Title Details of Associated Provisional Application No: Australian Patent Application October, 1992.

No. PL5101 filed The following statement is a full description of this invention, including the best method of performing it known to me: 2 TECHNICAL FIELD OF THE INVENTION THIS INVENTION relates to a jaw assembly and in particular but not limited to a multi-purpose jaw assembly for wood turning.

BACKGROUND ART It has been proposed by provide a jaw assembly where circular work pieces are held using arcuate jaw members. The arcuate jaw members are usually formed as quadrant shaped chuck plate having part annular ring members fitted to and a contiguous with the peripheral circumferential edge of the chuck plates. These known jaw assemblies lack versatility.

1 0 OUTLINE OF THE INVENTION It is an object of the present invention to alleviate at least to some degree the aforementioned problems associated with the prior art.

In one aspect, the present invention resides in a jaw assembly having a plurality of chuck plates adapted to be radially moved apart, each chuck plate having a plurality of ring member mounting means so that ring members can be fitted to the chuck plates at selectable radial locations, and a plurality of upstanding ring members being removably attached to each chuck plate, each said ring member having an undercut region to enhance the holding action of the ring member. The ring n .,nbers are typically undercut on opposed sides thereof and preferably are generally dovetail shape in transverse cross-section. Typically, the jaw assembly is provided with a plurality of interchangeable ring members of differing curvature to cater for different radial positions of the ring members on the chuck plates. Typically, when all ring members are fitted to the chuck plates, they form concentric rings.

In another aspect, the present invention resides in a jaw assembly as described above when used for wood fuming.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention can be more readily understood and be put into practical effect, reference will now be made to the accompanying drawings which illustrate preferred embodiment of the invention and wherein:- Figure 1 is a portion of a lathe equipped with a jaw assembly according to one embodiment of the present invention; Figure 2 is a schematic view illustrating two forms of ring members suitable for use with a jaw assembly of the type illustrated in Figure 1; Figure 3 is a further embodiment illustrating a jaw assembly according to the present invention; Figure 4 is a section through the assembly of Figure 3; and Figvre 5 is a detail in part section of a typical ring member suitable for use in a jaw assembly according to the present invention.

METHOD OF PERFORMANCE *~i Referring to the drawings and initially to Figure 1, there is illustrated part of a lathe showing a headstock 10 having a chuck 11 and fitted to the chuck are three chuck plates 12, 13 and 14. Fitted to the chuck plates 13 and 14 are ring members 15 and 16 respectively. A similar ring member to the ring members and 16 would normally be fitted to the chuck plate 12 in similar fashion to that shown in relation to the chuck plates 13 and 14 and to the ring members 15 and 16. The extra ring member has been omitted so that the ring members 15 and 16 can be viewed. As can be seen, each ring member 15 and 16 is undercut on opposite sides at 17 and 18 and 19 and 20 respectively so that as the chuck plates 12, 13 and 14 are driven apart radially by operation of the chuck 11, the undercut regions 18 and 20 can be used to hold the inside of a cylindrical or like object. Similarly, the chuck plates 12, 13 and 14 can be driven together in order to hold the outside of a circular object using the undercut surfaces 17 and 19.

This will of course will be the case when the third ring member is fitted to the chuck plate 12. As can be seen in Figure 1, the ring members 15 and 16 are fitted to the chuck plate and each chuck plate 12, 13 and 14 includes a plurality of fixing holes all of which have beer numbered 21. These are used so that ring 10 members of different size and curvature can be fitted to the chuck plates 12, 13 and 14. As can be seen in Figure 2, the ring members 15 and 16 are illustrated and a third ring member 22 which would normally be coupled to chuck plate 12 is also shown in Figure 2. Also in Figure 2 are ring members 23, 24 and which can be used instead of or in conjunction with the ring members 15, 16 and 22 in order to enable the chuck plates to be used to hold smaller ring-like work pieces. In the illustrated embodiment, three different sized sets of ring members are employed.

Referring to Figures 3, 4 and 5, there is illustrated a further embodiment of the present invention wherein this case in Figure 3, there is illustrated a jaw assembly 26 which employs four chuck plates 27, 28, 29 and 30 to form in conjunction with ring members 31, 32, 33 and 34 a four jaw assembly and in this regard, this is the only difference between the jaw assembly of Figure 3 of any substance and the jaw assemblies depicted in Figures 1 and 2. As can be seen in Figure 3, extra holes 35 are provided for fitting additional ring members to the plates 27, 28, 29 and 30. Figure 4 illustrates a typical section through the jaw assembly of Figure 3 and as can be seen, the ring members 32 and 31 are generally dovetail in section as can be seen in the section at 36. This ring member still includes undercut regions 37 and 38 and operate in similar fashion to the ring members employed in the jaw assembly of the embodiment of Figures 1 and 2. In all of the embodiments, the ring members are secured to the chuck plates from the rear through blind holes in the r:ig members 39 and a typical section adjacent a hole 39 is shown in Figure 5. As can be seen in Figure 5, the ring member in this case is ring member 32 and includes a screw hole 40 to :i o10 enable the ring member to be secured to its chuck plate 32.

It will be appreciated from the foregoing that although the section that is ,:i preferred and illustrated for the ring members is in the form of a dovetail having undercuts on both sides of the ring members any suitable shape which performs the same or similar function can be used. It will therefore be appreciated that whilst the above has been given by way of illustrative example of the present invention, many variations and modifications thereto will be apparent to those skilled in the art without departing from the broad ambit and scope of the 99.99 invention as set forth in the appended claims.

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Claims (9)

1. A jaw assembly having a plurality of chuck plates adapted to be radially moved apart, each chuck plate having a plurality of ring member mounting means so that ring members can be fitted to the chuck plates at selectable radial locations, and a plurality of upstanding ring members being removably attached to each chuck plate, each said ring member having an undercut region to enhance the holding action of the ring member.

2. A jaw assembly according to claim 1 wherein the ring members are undercut on opposed sides thereof and are generally dovetail shape in transverse cross-section.

3. A jaw assembly according to claim 1 or claim 2 wherein the jaw assembly :i is provided with a plurality of interchangeable ring members of differing curvature to cater for different radial positions of the ring members on the chuck plates.

4. A jaw assembly according to any one of the preceding claims wherein when all ring members are fitted to the chuck plates, they form concentric rings. wo

5. A jaw assembly according to any one of the preceding claims wherein the ooooo jaw assembly is used for wood turning. o.

6. A jaw assembly according to any one of the preceding claims wherein the oooo ring members are secured to a front side of the chuck plates, the chuck plates having front and rear sides, the ring members being secured to the chuck plates from the rear through blind holes in the ring members.

7. A jaw assembly according to any one of the preceding claims wherein the jaw assembly is a three or four jaw assembly having three and four chuck plates and ring members respectively. I I 7

8. A jaw assembly according to any one of the preceding claims wherein the chuck plates include a plurality of circumferentially and radially spaced holes so that concentric ring members can be interchangedly and selectively secured to the chuck plates.

9. A jaw assembly substantially as described with reference to Figure 1 and 2 or Figure 3 of the accompanying drawings. A wood turning lathe having a jaw assembly according to any one of the preceding claims. DATED this fifth day of October, 1993. "VICTOR VERRECCHIA By his Patent Attorneys TREVOR DREDGE ASSOCIATES *oo* *o I *4 I ABSTRACT A lathe showing a headstock 10 having a chuck 11 and fitted to the chuck are three chuck plates 12, 13 and 14. Fitted to the chuck plates 13 and 14 are ring members 15 and 16 respectively. A similar ring member to the ring members 15 and 16 would normally be fitted to the chuck plate 12 in similar fashion to that shown in relation to the chuck plates 13 and 14 and to the ring members 15 and 16. The ring members 15 and 16 are fitted to the chuck plate and each chuck plate 12, 13 and 14 includes a plurality of fixing holes all of which have been numbered 21. These are used so that ring members of different size and curvature can be fitted to the chuck plates 12, 13 and 14. *o o *g o ooo* o* o oo* ••go o* *o