GB2053747A

GB2053747A - Tool unit for vertical lathes

Info

Publication number: GB2053747A
Application number: GB8018566A
Authority: GB
Original assignee: Tovarny Strojirenske Techniky
Current assignee: Tovarny Strojirenske Techniky
Priority date: 1979-06-08
Filing date: 1980-06-06
Publication date: 1981-02-11
Also published as: RO81363B; IT1212420B; CS210846B1; JPS6322923B2; PL224806A1; YU150680A; JPS5633202A; YU43473B; PL138046B1; GB2053747B; DE3021410A1; FR2458340A1; RO81363A; IT8022597A0; FR2458340B3

Abstract

The invention relates to a tool unit for vertical lathes comprising a main holder 10 and at least one tool head 20, the main holder having connecting faces 11, and the tool head being inserted in the main holder and secured by a clamping element 30a. The connecting faces of the main holder are at an angle of 45 DEG to the axis of the tool unit and at an angle of delta =@-45 DEG to the cutting edge of the tool. <IMAGE>

Description

SPECIFICATION Tool unit for vertical lathes The invention relates to a tool unit for vertical lathes, enabling a simple and quick change of tool heads, allowing for adjustment of the cutting edge for finishing tool heads beyond the machine, eliminating the physically demanding manipulation with tools, and providing for a possible use of the same tool heads for longitudinal and transverse turning, thereby substantially reducing the required number of tool heads.

In currently used tool heads and lathe tools are clamped by means of three grooves, two being perpendicular and one parallel with the clamping face of the head, and three clamping screws. The tool heads are of substantial dimensions, particularly for lathe tools of a section 50 x 50 and 63 x 63mm.

When the lathe tools are sharpened the height of the cutting edge is changed, which in current practice is compensated for by inserting shimplates of different thickness under the body of the tool. Thus the stiffness of the clamping is reduced, frequently causing generation of self-excited vibrations. Repe atedfitting of the tool head with cutting tools is demanding on time, the exchange requiring stress and is disadvantageous from the point of view of labour safety. In the case of digitally controlled vertical lathes, repeated fitting of the tool head with lathe tools requires either a dismantling of the tool head and adjustment in some adjusting device and subsequent mounting by means of a special device, or a replacement of the dull lathe tool without dismantling the tool head and adjustment by means of a special adjusting device mounted on the machine.In both cases the exchange of the dull tool requires stopping the machine for a considerable period of time with a substantial increase of idle working time. Further disadvantages of known tool heads are the lowering of the maximum height of the turning face due to their length, determined by the length of the body of the lathe tool clamped in the tool head perpendicularly to the clamping face, and their weight which is about 0.2 to 0.4kN which makes manipulation difficult.

Atool unit according to this invention comprises a main holder and at least a single tool head, the connecting faces of the main holder being at an angle of 450 to the axis of the tool unit and at an angle of â = x- 450 to the cutting edge. The tool head is inserted in the main holder, for example in a recess of the main holder, and secured by a clamping element.

In one embodiment of the invention the clamping face of the main holder is made in the form of a two way dove tail tapering on both sides, or possibly a two way dove tail tapering on one side only. An opening is provided in the main holder extending into a female thread for an external thread of a clamping screw of the tool head. The clamping screw is provided below its head with a cut-off cylindrical surface. The clamping part of the clamping screw has a thread with an opposite lead to that of the external thread.

In another embodiment the connecting face of the main holder is arranged as a one way dove tail for a one way dove tail of the tool head. The connecting face is at an angle between 500 and 900 to the main plane cp which is parallel with the axis of the tool unit and with the cutting edge having a deviation angle A = 0. A female thread extending into an opening for a clamping screw is provided in the main holder.

A recess for adjustable cutting tools may be provided in the body of the tool head, the lateral face of the recess being at an angle of 450 to the connecting face. A female thread for a clamping screw for the adjustable cutting tool is provided in the body of the tool head.

A recess for a lathe tool may be provided in the tool head, the lateral face of the recess being at an angle of 450 to the connecting face. Female threads are provided for external threads of clamping screws for the lathe tools.

By way of example, specific embodiments in accordance with the invention will be described with reference to the accompanying drawings in which: Figure 1 is an elevation of a tool unit with connecting faces in the shape of a two way dove tail tapering at both sides; Figure 2 is a view in the direction of the letter Q in Figure 1; Figure 3 is a section along the line A-A in Figure 1; Figure 4 is a view in the direction of the letter Pin Figure 1; Figure 5 is an elevation of an alternative arrangement in which the connecting faces are in the shape of a two way dove tail tapering at one side only; Figure 6 is a section along the line B-B in Figure 5; Figure 7 is an elevation of another tool unit having connecting faces in the shape of a one way dove tail; Figure 8 is a section along the line C-C in Figure 7;; Figure 9 is an elevation of a further tool unit having two inclined connecting faces with perpendi cularlyfitted openings; Figure 10 is a section along the line D-D in Figure 9; Figure 11 is an elevation of a still further tool unit having a recess for clamping adjustable cutting tools in a tool head; Figure 12 is a section along the line E-E in Figure 11; Figure 13 is an elevation of another tool unit having a recess for clamping lathe tools in the tool head; Figure 14 is a section along the line F-F in Figure 13; and Figure 15 is a view of a cutting tool for lathes and planing machines.

Referring to Figures 1 to 6, a tool unit for a vertical lathe comprises a main holder 10, a tool head 20, clamping elements 30 and adjustable nozzles 60.

Two connecting faces 11 for the tool head 20 are provided on the main holder 10, which are at an angle of 450 to the axis 0 of the tool unit and at an angle 5 = x - 450 to the cutting edge 22, where x is the angle of adjustment of the cutting edge 22. The arrangement enables an alternative use of a tool head 20 for longitudinal and transverse turning. If the tool head 20 is clamped to the left connecting face 11 as shown in Figure 1, the tool unit is used for longitudinal turning in the direction of the axis Z at the adjustment angle x of the cutting edge. Alternatively, clamping of the tool head 20 to the right connecting face 11 enables a transverse turning in the direction of the axis X at the same adjustment angle x of the cutting edge.The connecting face 11 has either an internal two way dove tail tapering on both sides (see Figures 4) or an internal two way dovetail 12 tapering on one side only (see Figures 5 and 6), in which an external dove tail 21 ofthetool head 20 is inserted in overlapping relation. Thereby the tool head 20 may be clamped to the connecting face by a clamping screw 30a. The clamping part 33 of the clamping screw 30a is formed as a thread with an opposite lead to that of the external thread 35, thus clamping the tool head 20 independently of its fitting into the main holder 10 with predetermined allowances.Turning of the clamping screw 30a into a position where the cut-off 32 of its head 31 is facing the connecting face 11 and is parallel therewith enables the tool head to be replaced without completely screwing out the clamping screw 30a, thereby substantially reducing exchange time. The tool unit is clamped to a slide shoe orto a turret block of a vertical lathe by the clamping face 13. The cutting liquid is supplied to the cutting edge 22 through bores in the main holder 10 and adjustable nozzles 60.

In the embodiment of tool unit shown in Figures 7 and 8, the connecting faces 11 of the main holder 10 are at an angle between 500 and 900 to the main plane ep which is parallel with the axis 0 of the tool unit and with the cutting edge 22 at an angle k = 0 , and at an angle of 450 to the axis 0. An external dove tail 21a of the tool head 20 is seated against a connecting face 11 which is formed as a one way dove tail 12a. A positioning bolt 40 screwed in in the main holder 10 at an angle cp and located in a recess 23 of the tool head 20 determines the position of the tool head with respect to the main holder 10.The clamping force of the clamping screw 30a screwedin in the positioning bolt 40 is transmitted to the tool head 20 by the head 31 of the screw 30a engaging in a recess 24 in the tool head 20.

Figures 9 and 10 show an embodiment in which the connecting faces 11 of the main holder 10 are at an angle between 500 and 900 to the plane (p, which is parallel with the axis 0 of the tool unit and with the cutting edge 22 at an angle of inclination X equal to 0 , and at an angle of 450 to the axis 0. Cylindrical openings 12b, into which a bolt 21b of the tool head 20 is engaged, are provided in the main holder 10 perpendicular to the connecting faces 11. The clamping screw 30a has its clamping surface 33 resting against the inclined cut-off 25 of the bolt 21 b and generates a clamping force in the direction of the axis of the bolt 21 b and receives simultaneously the torque of the cutting force.

In the embodiment of Figures 11 and 12, there is provided a recess 26 for adjustable cutting tools in the body of the tool head 20. The lateral face 27 of the recess is at an angle of 450 to the connecting face 11. This position of the recess enables both a longitudinal and transverse turning by a tool head 20 fitted with the respective tool. The suitable cutting tool is clamped in the recess 26 by a clamping screw, screwed-in in a female thread 27a. The adjustability of the cutting tool is secured by two screws screwedin in the body of the cutting tool, the screws resting against lateral faces 27 and 27b of the recess 26.

Figures 13 and 14 show an embodiment in which a recess 28 for lathe tools is provided in the body of the tool head 20. The lateral face 29 of the recess is again at an angle of 450 to the connecting face 11.

The lathe tool is clamped in the recess 28 by means of clamping bolts 50.

The invention may also be applied to turrent heads of digitally controlled lathes. The invention may furthermore be applied to lathes and planing machines as indicated in Figure 15, in which the connecting face 11 of the main holder 10 is at an angle of 450 to the axis of the main holder and at an angle 6 = x - 450 to the cutting edge 22 of the tool head 20. As in the case of the earlier described embodiments of the tool unit, tool heads 20 may be clamped with equal advantage in the right and left parts of the main holder 10.

An advantage of the tool units described above is that they provide a simple and quick replacement of the tool head which performs the function of a cutting tool and its rigid clamping. When exchanging a cutting tool for sharpening a manipulation with a tool head of a weight of 10 to 15 N takes place, which is convenient from the point of view of safety of labour and reduction of physical stress of the operator. As the accuracy of the position of the cutting edge relative to the connecting face on the tool head and the accuracy of the connecting faces can be maintained within allowances admissible for rough machining, the cutting edge need not be adjusted in the case of rough machining on digitally controlled vertical lathes. For finishing operations, tool heads are provided with a recess for clamping adjustable cutting tools. For example, a recess for clamping lathe tools enables an adjustment of the cutting edge beyond the machine in a fixture with mechanical stops or in a simple optical adjusting device.

The position of the connecting faces in the main body enables an alternative application of any tool head for longitudinal and transverse turning at the same adjusted angle of the cutting edge, thus reducing the assortment of tool heads by 50%. The small dimensions of the tool head and the simple connecting face with a single clamping element make it possible to reduce substantially the length of.

the tool unit in comparison with known tool heads, thereby increasing the maximum height of the turning face.

Claims

1. Atool unit for vertical lathes comprising a main holder and at least one tool head, the main holder having connecting faces, and the tool head being inserted in the main holder and secured by a clamping element, whereby the connecting faces of the main holder are at an angle of 450 to the axis of the tool unit and at an angle 6 = x - 450 to the cutting edge of the tool.

2. Atool unit as claimed in Claim 1, wherein the connecting faces of the main holder have the shape of a two way internal dove tail tapering at least on one side, an opening extending into a female thread provided in the main holder, a clamping screw with a screw head having below the head a cylindrical part with a cut-off face, the external thread of the clamping screw being adapted for engagement into the fecal thread of the opening of the main holder, and the clamping surface of the clamping screw being shaped as a thread with a lead opposite to the lead of the thread of the clamping screw.

3. Atool unit as claimed in Claim 1, wherein the connecting face of the main holder is formed as a one way dove tail for a one way dove tail of the tool head, the connecting face being at an angle between 50 and 900 to a plane which is parallel with the axis of the tool unit and with the cutting edge having an inclination angle X = 0 , and wherein there is provided an opening in the main holder having a female thread portion, a positioning bolt with an external thread adapted for engagement in the female thread, an internal female thread in the positioning bolt, a clamping bolt with a thread adapted for engagement in the internal female thread of the positioning bolt, a recess provided in the tool head for the positioning bolt and another recess for the clamping bolt.

4. Atool unit as claimed in Claim 1,wherein there is provided a cylindrical opening in the main holder perpendicular to the connecting face of the main holder, a bolt in the tool head adapted for engagement with the opening, a cut-off face on the bolt, the connecting face being at an angle between 500 and 900 to a plane parallel with the axis of the tool unit and with the cutting edge having an inclination angle k = 0 , a clamping screw, and an opening in the main holder having an internally threaded portion for reception of the clamping screw.

5. Atool unit as claimed in Claim 1, including a recess in the tool head for adjustable cutting tools, a lateral wall of the recess being at an angle of 450 to the connecting face of the main holder, a clamping screw for the adjustable tool, and a female thread in the body of the tool head for the clamping screw.

6. A tool unit as claimed in Claim 1, including a recess in the body of the tool head for lathe tools, a lateral wall of the recess being at an angle of 450 to the connecting face of the main holder, clamping screws for said lathe tools, and female threads provided in the tool head for the clamping screws.

7. Atool unitforvertical lathes substantially as hereinbefore described with reference to and as shown in the accompanying drawings.