GB2243099A

GB2243099A - Retaining tool holders in tool post

Info

Publication number: GB2243099A
Application number: GB9006163A
Authority: GB
Inventors: Hugh Parker Bowman
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-03-19
Filing date: 1990-03-19
Publication date: 1991-10-23
Anticipated expiration: 2010-03-19
Also published as: GB2243099B; GB9006163D0

Abstract

The post comprises a block (12) having a Morse tapered hole formed therein accepting a mating tool holder, the tapered hole allowing a tang (18) projecting through the block. The tang (18) is slotted and via the slot is engaged by a locking means (23) capable of pulling the tool into the hole (13). The locking means (23) is a disc with a cutout to accept initially the tang (18) and which is rotated to engage with a cut-out in the tang. Rotation causes axial disc movement, by a screw thread or helical disc form, to provide the tool pulling. <IMAGE>

Description

IMPROVEMENTS IN TOOLING This invention relates to an improved tool post for supporting a machining tool adjacent to a work piece in a lathe or the like shaping machine.

In the machining of a work piece there is a requirement to use a range of different tools and these can be supported on an indexing or turret tool post whereby tools prefixed in the tool post can be rapidly brought to bear on the work piece one after another as the machining process proceeds. This invention relates to an alternative to the turret or indexing tool post in which a range of tools are brought to bear not by being premounted in the tool post but by being rapidly inserted in the tool post when required and rapidly removed (for replacement by the next tool required) when the particular machining operation for which that tool is required has been completed.

According to this invention a tool post comprises a support block having a tapered hole formed therein, at least two different tool holders each having a body portion tapered to match the hole, said body portion having, at the wider end thereof, means to support a machine tool and, at the narrower end thereof one component of a quick-release locking means. Suitably, said one component is a slotted tang, the other component of the quick release locking means being turnably mounted on the support block and having a groove to receive the tang and a cam surface extending from the groove to engage the slot in the tang.

Desirably the tapered hole and body portion are provided with a Morse taper (e.g. a No. 1, 2, 3 or 4 Morse taper) and the locking means is screw-threaded into the support block to one side of the tapering hole therein. As an alternative to screw-threading the locking means in the support block it can be turnable but axially fixed in the support block and can engage the slot in the tang via a part-helical cam surface on the locking means.

Among the tools that can be mounted in the means at the wider end of the body portion can be mentioned drills, reamers, knurls, boring bars, parting off blades and lathe cutters.

One embodiment of tool post in accordance with the invention will now be described, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a perspective view of a tool post with a tool holder carrying a drill and ready for mounting on the bed of a centre lathe, Figure 2 shows the tool post of Figure 1 with a different tool holder located therein, Figure 3 is a view of the tool holder of Figure 2 removed from the support block, Figure 4 is a view of the quick release locking means removed from the support block, and Figure 5 is a still further tool holder in the form of a boring bar.

The support block 10 of the illustrated tool post is manufactured from an L-shaped member 11 and a rectangular cross-section block 12 clamped together by bolts/screws (not shown). The block 12 is provided with a through bore 13 machined to a Morse taper and is provided with a screw threaded blind h#1#;"-#to;: one side of the -bore#- 13- tat: the: narrow end thereof.

The machine tools are carried at the wide end of a tool holder 14, 15, 16 which has a matching Morse taper on a body portion 17 and a tang 18 at the narrow end with a slot 19 therein.

A locking means 20 is threaded into the blind hole in the block 12 and has a screw-threaded shaft 21, a Tommy bar 22 and a tightening disc 23. The disc 23 has a groove 24 therein to accommodate the tang 18.

The procedure for fitting a tool holder (say 14) in the block 10, involves screwing the locking means 20 into the block 12 the required amount, aligning the groove 24 in the disc 23 with the end of the bore 13, passing the tool holder 14 through the bore with the slot 19 in the tang 18 on the side of the bore 13 on which the locking means 20 is located so that the tang 18 passes along the groove 24 and finally, using the Tommy bar 22, unscrewing the locking means 20 a part turn to cause a cam surface on the disc 23 to ride round in the slot 19 as it pulls the two Morse tapers into full engagement. The tool holder 14 supports a drill 30, the tool holder 15 a carriage 31 for clamping a block of tool steel in place and the tool holder 16 a boring bar 32 with cutting tip 33. Clearly a wide range of other tools can be supplied.

The tool holder 15 could incorporate means permitting the carriage 31 to be rotated about the axis of the bore 13. If the locking means 20 permit it, the tool post can incorporate indexing within the Morse taper bore 13 to permit easier pre-setting of the orientation of the tool holder 15 in the block 10.

The disc 23 could have a surface which is part-helically inclined to the axis of the shaft 21 of the locking means 20 and if this is provided, the shaft 21 need not be screw-threaded, it could be captive in the block 12 allowing rotation about the axis of shaft 21 but not movement in the axial direction.

Known tool posts require a large amount of machining in themselves with a proliferation of screws to effect the necessary securing and adjustment A tool post according to this invention has the following advantages: 1) Relative simplicity of design and ease of manufacture of the tool holder, 2) Elimination of individual settings, 3) Single adjustment of Morse Taper socket to Lathe centre height, 4. Fast (2 to 3 seconds) and repetitive accuracy of the location of the tool holder, and 5) Absolute rigidity.

The invention can be used on centre lathes and on other special purpose machines.

Claims

1. A tool post comprising a support block having a tapered hole formed therein, at least two different tool holders each having a body portion tapered to match the hole, said body portion having, at the wider end thereof, means to support a machine tool and. at the narrower end thereof one component of a quick-release locking means.

2. A tool post according to claim 1, in which said one component of a quick-release locking means is a slotted tang and the other component of the quick-release locking means is turnably mounted on the support block ane has a groove to receive the tang and a surface extending from the groove to engage the slot in the tang.

3. A tool post according to claim 1 or claim 2. n which the tapered hole and body portion of each tool are provided with a Morse taper and the locking means is screwthreaded into the support block to one side of the taDrin hole therein.

4. A tool post according to claim in in wnich the locking means is turnable in the support block but is axially fixed in the support block and engages the slot in the tang via a part-helical cam surface on tne locking means.

5. A tool post substantially as hereinbefore described with reference to the accompanying drawing.