GB1569058A - Machine-tool tool-mounting assembly - Google Patents

Description

(54) MACHINE-TOOL TOOL-MOUNTING ASSEMBLY (71) I, ROBERT NEIL PLATr, a British Subject of 124 Sinderland Road, Altrincham, Cheshire, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a machine-tool tool-mounting assembly for use in mounting tools on a machine tool, for example on a lathe and is an improvement in or modification of the invention described and claimed in British Patent Specification No.

8,a47.

According to the present invention there is provided a machine-tool tool-mounting assembly for use in mounting tools on a machine-tool, for example on a lathe, comprising a supporting plate and a mounting plate mounted parallel to the supporting plate on one side thereof and rotatable through at least 360 about an axis perpendicular to the supporting plate, the mounting plate having a plurality of tool holders for holding respective tools, the supporting plate being provided with a clamping arrangement whereby the supporting plate may be clamped to an external sleeve of a machine tool, the assembly also comprising index means provided on the supporting plate and cooperating with the mounting plate to render it indexable relative to the supporting plate, so enabling the holders to be selectively located in axial alignment with an aperture extending through the supporting plate and the clamping arrangement.

Each of the tool holders of the assembly of the present invention may comprise a respective generally cylindrical recess in the mounting plate for the reception of a respective thread cutting die, or each tool holder may be adapted for the reception of a drill, for example by being formed as a chuck.

Alternatively each tool holder may comprise a respective extension tube for the reception of drills having morse taper shanks.

The present invention includes a lathe provided with the machine-tool tool-mount mg assembly aforesaid.

The present invention will hereinafter be further described by way of example with reference to the accompanying drawings in which: Fig. 1 is a side elevation of an assembly in accordance with the present invention shown attached to the tailstock of a lathe; Fig. 2 is a perspective view of the assembly of Fig. 1 with the mounting plate and supporting plate shown separated; and Fig. 3 is an end elevation of the assembly of Figs. 1 and 2.

Referring to Fig. 1, the assembly is designated as a whole by the numeral 10 and is shown attached to a tailstock 11 of a lathe.

The assembly 10 comprises a mounting plate 12, a supporting plate 13 on which the mounting plate is rotationally disposed, and a clamping arrangement 14 securely fixed to, and thereby forming part of, the mounting plate 13. The whole assembly 10 is clamped to the outside of a sleeve 15 formed by the protruding portion of a cylinder 16 clamped within the tailstock 11 and having an internal morse taper bore.

As may be seen from Fig. 2, the mounting plate 12 is provided with three circular bores 17, 18 and 19 into which are fitted tapping dies 20, 21 and 22 respectively. A pivot shaft 23 is fixed to the disc-like mounting plate 12 and extends from the mounting plate 12 with its central axis passing through the circumcentre of the centres of the dies 20, 21 and 22. The pivot shaft 23 has a tapered free end portion 24 and an annular groove 25 adjacent the taper portion. The supporting plate 13 is provided with a peg 26 for engagement with one of three bores 27 in the mounting plate 12 and serves to locate a respective one of bores 17, 18, and 19 in alignment with a circumferentially disposed bore in the supporting plate 13 into which the clamping arrangement 14 is fitted.The clamping arrangement 14 comprises a housing 28 with a cylindrical portion 29, an end section of which of external diameter corresponding to the internal diameter of the circumferentially disposed bore in the supporting plate 13 is keyed within said circumferentially disposed bore to pre vent relative rotation between plate 13 and housing 28.

The cylindrical portion 29 has an internal bore, in axial alignment with the bore in the supporting plate 13, and which opens out into a bore 30 of larger diameter in the main body of the housing 28. A section of cylindrical portion 29, adjacent the section extending into the bore in the supporting plate, has an external diameter greater than the internal diameter of the bore in the supporting plate and serves to space the main body of the housing 28 from the supporting plate 13. A split ring 31 is fitted within the bore 30 and is acted upon on one side by a sloping surface 32 (Fig. 3) of a cotter pin 33 which extends substantially tangentially of the split ring 31 within a bore 34 in the housing 28 of the clamping arrangement 14. The cotter pin 33 is screw threaded along an end portion 35 which extends out of the bore 34 and a clamping nut 36 is screwed onto the portion 35.When the nut 36 is tightened the pin 33 is drawn through the bore 34 so that the surface 32 bears upon the one side of the ring 31 thereby closing the ring. By this means the supporting plate 13 may be clamped to the sleeve 15, the nut 36 being tightened after the clamping arrangement has been slipped over the sleeve 15.

The mounting plate 12 is pivotally attached to the supporting plate 13 by passing the pivot shaft 23 into a central bore 37 in the supporting plate. A locking member 38 is slidably mounted on the supporting plate 13 by means of two screws 39 screwed into corresponding threaded bores in the supporting plate and extending through a slot 40 in the locking member. The locking member is urged to the right in the drawing (Fig. 3) by the action of a spring 41.

When the pivot shaft 23 is pushed into the bore 37 the tapered portion 24 engages one side 42 (acting as an engagement tooth) of a semi-circular cut-out portion 43 and displaces the locking member 38 against the action of spring 41 until the shaft 23 is able to move further through the bore 37 and the tooth 42 snaps into engagement with the annular groove 25, the peg 26 at the same time engaging with one of the bores 27 in the mounting plate 12. When a different tapping die 20 is to be brought into alignment with the circumferentially disposed bore in the supporting plate 13 the locking member 38 must first be displaced against the action of spring 41 to enable the mounting plate 12 and pivot pin 23 to be displaced axially to bring the peg 26 out of engagement with the corresponding one of bores 27.The mounting plate is then pivoted about pin 23 until another of the bores 27 is brought into alignment with peg 26 such that the required one of bores 17, 18 and 19 is in alignment with the bore in the supporting plate 13. The mounting plate 12 is then pushed against the supporting plate 13 until the tooth 42 once again engages annular groove 25 thus locking the mounting plate 12 and supporting plate 13 together.

The clamping arrangement enables a particularly secure attachment to be made between the assembly 10 and the tail stock 11 with less risk of slipping occurring compared, for example, with the morse taper arrangement described in my British Patent Specification No. 1,228,847.

WHAT I CLAIM IS: 1. A machine-tool tool-mounting assembly, for use in mounting tools on a machine-tool, for example on a lathe, comprising a supporting plate and a mounting plate mounted parallel to the supporting plate on one side thereof and rotatable through at least 360" about an axis perpendicular to the supporting plate, the mounting plate having a plurality of tool holders for holding respective tools, the supporting plate being provided with a clamping arrangement whereby the supporting plate may be clamped to an external sleeve of a machine tool, the assembly also comprising index means provided on the supporting plate and cooperating with the mounting plate to render it indexable relative to the supporting plate, so enabling the holders to be selectively located in axial alignment with an aperture extending through the supporting plate and the clamping arrangement.

2. An assembly as claimed in claim 1 in which the clamping arrangement comprises a housing, a split ring disposed within a bore of the housing, and a screw threaded cotter pin adapted to close the split ring on the tightening of a nut.

3. An assembly as claimed in claim 2 in which the housing of the clamping arrangement has a hollow cylindrical portion a section of which extends into a bore in the supporting plate and is keyed therein to prevent relative rotation between the supporting plate and the housing of the clamping arrangement.

4. An assembly as claimed in claim 3 in which the hollow cylindrical portion of the housing comprises a section, adjacent the section extending into the bore in the supporting-plate, of outer diameter greater than the internal diameter of said bore in the supporting plate, said adjacent section serving to space a main section of the housing of the clamping arrangement, from the supporting plate.

5. An assembly as claimed in claim 4 in which the bore for the split ring is formed in the main section of the housing of the clamping arrangement and is axially aligned with the bore in the hollow cylindrical portion.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (16)

**WARNING** start of CLMS field may overlap end of DESC **. vent relative rotation between plate 13 and housing 28. The cylindrical portion 29 has an internal bore, in axial alignment with the bore in the supporting plate 13, and which opens out into a bore 30 of larger diameter in the main body of the housing 28. A section of cylindrical portion 29, adjacent the section extending into the bore in the supporting plate, has an external diameter greater than the internal diameter of the bore in the supporting plate and serves to space the main body of the housing 28 from the supporting plate 13. A split ring 31 is fitted within the bore 30 and is acted upon on one side by a sloping surface 32 (Fig. 3) of a cotter pin 33 which extends substantially tangentially of the split ring 31 within a bore 34 in the housing 28 of the clamping arrangement 14. The cotter pin 33 is screw threaded along an end portion 35 which extends out of the bore 34 and a clamping nut 36 is screwed onto the portion 35.When the nut 36 is tightened the pin 33 is drawn through the bore 34 so that the surface 32 bears upon the one side of the ring 31 thereby closing the ring. By this means the supporting plate 13 may be clamped to the sleeve 15, the nut 36 being tightened after the clamping arrangement has been slipped over the sleeve 15. The mounting plate 12 is pivotally attached to the supporting plate 13 by passing the pivot shaft 23 into a central bore 37 in the supporting plate. A locking member 38 is slidably mounted on the supporting plate 13 by means of two screws 39 screwed into corresponding threaded bores in the supporting plate and extending through a slot 40 in the locking member. The locking member is urged to the right in the drawing (Fig. 3) by the action of a spring 41. When the pivot shaft 23 is pushed into the bore 37 the tapered portion 24 engages one side 42 (acting as an engagement tooth) of a semi-circular cut-out portion 43 and displaces the locking member 38 against the action of spring 41 until the shaft 23 is able to move further through the bore 37 and the tooth 42 snaps into engagement with the annular groove 25, the peg 26 at the same time engaging with one of the bores 27 in the mounting plate 12. When a different tapping die 20 is to be brought into alignment with the circumferentially disposed bore in the supporting plate 13 the locking member 38 must first be displaced against the action of spring 41 to enable the mounting plate 12 and pivot pin 23 to be displaced axially to bring the peg 26 out of engagement with the corresponding one of bores 27.The mounting plate is then pivoted about pin 23 until another of the bores 27 is brought into alignment with peg 26 such that the required one of bores 17, 18 and 19 is in alignment with the bore in the supporting plate 13. The mounting plate 12 is then pushed against the supporting plate 13 until the tooth 42 once again engages annular groove 25 thus locking the mounting plate 12 and supporting plate 13 together. The clamping arrangement enables a particularly secure attachment to be made between the assembly 10 and the tail stock 11 with less risk of slipping occurring compared, for example, with the morse taper arrangement described in my British Patent Specification No. 1,228,847. WHAT I CLAIM IS:

1. A machine-tool tool-mounting assembly, for use in mounting tools on a machine-tool, for example on a lathe, comprising a supporting plate and a mounting plate mounted parallel to the supporting plate on one side thereof and rotatable through at least 360" about an axis perpendicular to the supporting plate, the mounting plate having a plurality of tool holders for holding respective tools, the supporting plate being provided with a clamping arrangement whereby the supporting plate may be clamped to an external sleeve of a machine tool, the assembly also comprising index means provided on the supporting plate and cooperating with the mounting plate to render it indexable relative to the supporting plate, so enabling the holders to be selectively located in axial alignment with an aperture extending through the supporting plate and the clamping arrangement.

2. An assembly as claimed in claim 1 in which the clamping arrangement comprises a housing, a split ring disposed within a bore of the housing, and a screw threaded cotter pin adapted to close the split ring on the tightening of a nut.

3. An assembly as claimed in claim 2 in which the housing of the clamping arrangement has a hollow cylindrical portion a section of which extends into a bore in the supporting plate and is keyed therein to prevent relative rotation between the supporting plate and the housing of the clamping arrangement.

4. An assembly as claimed in claim 3 in which the hollow cylindrical portion of the housing comprises a section, adjacent the section extending into the bore in the supporting-plate, of outer diameter greater than the internal diameter of said bore in the supporting plate, said adjacent section serving to space a main section of the housing of the clamping arrangement, from the supporting plate.

5. An assembly as claimed in claim 4 in which the bore for the split ring is formed in the main section of the housing of the clamping arrangement and is axially aligned with the bore in the hollow cylindrical portion.

6. An assembly as claimed in claim 5

in which the main portion of the housing of the clamping arrangement is provided with a bore for the cotter pin, which bore extends in a direction at a right angle to the axis of the bore for the split ring.

7. An assembly as claimed in any preceding claim in which each of the tool holders is constituted by a cylindrical recess in the mounting plate for the reception of a respective thread cutting die.

8. An assembly as claimed in any of claims 1 to 6 in which each of the tool holders is adapted for the reception of a drill.

9. An assembly as claimed in claim 8 in which three holders are provided which comprise respective chucks.

10. An assembly as claimed in any of claims 1 to 6 in which the tool holders comprise respective extension tubes for the reception of drills having morse taper shanks.

11. An assembly as claimed in any preceding claim in which the mounting plate comprises a disc having a pivot shaft extending axially from one side thereof, such shaft having a tapered portion at its free end and an annular notch or reduced diameter portion near to but spaced from the tapered portion.

12. An assembly as claimed in claim 11, wherein locking means is provided for locating the mounting plate axially of the supporting plate and includes a locking plate slidably mounted on the side of the supporting plate remote from the mounting plate, said locking plate being provided with a tooth for engaging the notch or reduced diameter portion of the mounting plate shaft.

13. An assembly as claimed in claim 12 in which the locking plate is biassed such that the tooth is urged into engagement with the notch or reduced diameter portion of the mounting plate shaft.

14. An assembly as claimed in any preceding claim in which the index means comprises an indexing peg extending through the supporting plate for engagement into corresponding recesses provided in the adjacent side of the mounting plate so as to locate a selected one of the holders in the operative position.

15. A machine-tool tool-mounting assembly substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

16. A lathe provided with a machinetool tool-mounting assembly as claimed in any preceding claim.