JPH0919848A - Revolution indexing device with three-piece coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make large the inside diameter of a hollow in the axis part of a revolving shaft by interposing a bearing between a stationary side indexing coupling and a revolving side indexing coupling, and supporting a revolving body rotatably on a stationary table. SOLUTION: A turret head 1 is rotatably supported on the body of tool rest (stationary table) 3 through a bearing 20 interposed between a stationary side indexing coupling 7 and a revolving side indexing coupling 8. A ring-shaped groove 21 having V-section provided at the periphery of the stationary side coupling 7 is used as inner ring of the bearing 20, while the ring-shaped groove 22 having V-section provided at the bore of the revolving side coupling 8 is used as the outer ring of the bearing 20, wherein such a structure is introduced that the bearing 20 is consolidated with the two couplings 7, 8. Thereby a hollow in the axis part of the revolving shaft can be set of large without arranging the tool rest largely in the axial direction of the turret head 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary indexing device for a revolving structure such as a turret and a revolving table in a machine tool.

[0002]

2. Description of the Related Art As a rotary indexing device of this type, a three-piece coupling is provided in which the axial movement of a heavy turret or a rotary table is replaced with the axial movement of a light indexing coupling to shorten the indexing time. The turning indexing device used is known (see, for example, JP-A-4-35844 and JP-A-6-23655).

FIG. 2 shows an example of a conventional rotary indexing device using a three-piece coupling. The turret head (revolving body) 1 has a hollow indexing shaft 2 in the central portion,
The indexing shaft 2 is rotatably supported by a cylindrical shaft portion 4 of a tool rest main body (fixed base) 3 via a bearing 5, and the turret head 1 is indexed via a gear by an unillustrated indexing motor. It can be rotated. Between the turret head 1 and the turret body 3, a stationary indexing colling 7 fixed to the turret body 3 and a concentric outside of the coupling 7 are fixed to the turret head 1. A three-piece coupling 6 is provided, which comprises a rotating side indexing coupling 8 and a fixing indexing coupling 9 that meshes with both couplings 7, 8 at the same time. As the couplings 7 to 9, a Curbic coupling is usually used. An annular hydraulic cylinder 10 is concentrically provided outside the indexing shaft 2 in the tool rest body 3, and an indexing coupling for fixing is attached to an end surface of an annular piston 11 fitted in the hydraulic cylinder 10. 9 is provided. When hydraulic pressure acts on the right side cylinder chamber 10a of the hydraulic cylinder 10 and the piston 11 moves to the left side, the fixing index coupling 9 and both couplings 7,
The engagement with 8 is released, the turret head 1 can be turned, and it is rotated to the indexing position. At this time, the turning side index coupling 8 is also moved slightly to the left side to avoid contact with the tool rest body 3, and a gap is created between the swivel side index coupling 8 and the tool rest body 3. This is because the assembly of the bearing 5 is adjusted so that a preload is applied to the bearing 5 when the fixing index coupling 9 is in pressure contact with both couplings 7 and 8. On the other hand, the hydraulic cylinder 10
When hydraulic pressure acts on the left cylinder chamber 10b of the turret 10 and the piston 11 moves to the right, the fixing indexing coupling 9 and the couplings 7 and 8 come into engagement pressure contact with each other, and the turret head 1
Is clamped at the indexing position.

[0004]

In the conventional rotary indexing device described above, not only is the thickness of the three-piece coupling mechanism itself large, but the indexing shaft 2 of the turret head 1 is inside the three-piece coupling mechanism 6. Since it is supported by the tool rest main body 3 via the bearing 5, the support structure is complicated, and there is a problem that the inner diameter of the tool rest 12, that is, the inner diameter D1 of the cylinder shaft portion 4 is limited and cannot be large. Therefore, for example, in the case where the rotary tool can be mounted on the turret head 1, it is difficult to provide the drive mechanism for the rotary tool in the hollow portion of the tool post 12 at the inner diameter, that is, in the rotary shaft center portion of the turret head 1. It was

Further, as shown in FIG. 3, if the bearing 5 is arranged at a position having substantially the same diameter as the three-piece coupling mechanism 6, the inner diameter of the tool rest 12 can be made large, but the tool rest 12 is a turret. It becomes larger in the axial direction of the head 1. Therefore, if the axial length of the entire machine is fixed, the distance between the tool rest 12 and the headstock or the like (not shown) arranged in front of the turret head 1 (on the left side in FIG. 3) becomes short, There is a problem that the processing area becomes narrow.

The present invention has been made in view of the problems of the above-described conventional device, and has a simple structure, the entire device can be made compact, and the inner diameter of the hollow hole of the pivot axis portion is increased. An object of the present invention is to provide a swivel indexing device using a three-piece coupling in which a rotary tool driving mechanism can be easily incorporated.

[0007]

In order to achieve the above object, the present invention provides a stationary side index coupling fixed to a fixed base and a stationary side index coupling fixed to a revolving structure. A concentric swivel side indexing coupling and a fixing indexing coupling that meshes with both couplings at the same time are provided, and the fixing indexing coupling moves in the axial direction of the swivel body. In a swivel indexing device using a three-piece coupling for engaging and disengaging the two couplings, a bearing body is interposed between the stationary side indexing coupling and the swivel side indexing coupling, The revolving structure is rotatably supported by the fixed base. It is preferable that the bearing body is integrated with the stationary side index coupling and the turning side index coupling of the three-piece coupling mechanism.

With the above structure, the indexing shaft of the turret (revolving body) and the cylindrical shaft portion of the tool rest main body (fixed stand) supporting the same in the conventional apparatus are deleted, the structure is simplified, and the tool rest is The hollow hole at the center of the turning shaft can be made large without increasing the size of the turning body in the axial direction. Therefore, it becomes easy to incorporate the rotary tool drive mechanism in the turning axis of the turret.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example in which the present invention is applied to a turret tool rest of a lathe, and a three-piece coupling mechanism which is a main part of a rotary indexing device and its operation are shown in FIG. Since it is the same as the above, the same components will be assigned the same reference numerals and explanations thereof will be omitted.

The turret head 1 is rotatably supported by a tool rest main body (fixed base) 3 through a bearing 20 interposed between a stationary side index coupling 7 and a turning side index coupling 8. This is a structure in which the indexing shaft 2 and the cylinder shaft portion 4 of the conventional device shown in FIG. 2 are eliminated. In the illustrated example, the annular groove 21 having a V-shaped cross section provided on the outer peripheral surface of the stationary side index coupling 7 is used as the inner ring of the bearing 20, and the V-shaped cross section provided on the inner peripheral surface of the orbiting side index coupling 8. The annular groove 22 of is used as the outer ring of the bearing 20, and
It has a structure integrated with. In addition, the surface of the stationary side index coupling 7 is slightly projected from the tool rest main body 3 side (the right side in FIG. 1) of both couplings 7 and 8, and the fixed index coupling 9 is fixed to both couplings 7. When engaged in pressure contact with 8, the swivel side indexing coupling 8 is pushed to preload the bearing 20. Also, the bearing 2
Although an example in which a steel ball is used as 0 is shown, it is also possible to use a roller. Further, in the above embodiment, an example in which it is applied to a turret of a lathe has been shown, but the present invention can also be applied to a revolving structure such as a revolving table.

[0012]

As described above, according to the present invention,
Since the indexing shaft and its supporting means provided in the axial center of the revolving structure in the conventional device are deleted, the structure is simplified and the entire device can be made compact. Moreover, since the inner diameter of the hollow hole at the center of the turning axis can be increased,
When applied to a turret, it is easy to incorporate the rotary tool drive mechanism in the turning shaft center part. Further, since the moment of inertia of the revolving structure is reduced, the revolving indexing time can be further shortened and the torque required for revolving is also reduced. Moreover, since the diameter of the bearing body that rotatably supports the revolving unit is large, the holding rigidity at the time of revolving is high. Furthermore, the number of parts is reduced and the cost is reduced, which is a great practical effect.

According to the second aspect of the present invention, since the bearing body is integrated with the stationary side indexing coupling and the turning side indexing coupling of the three-piece coupling mechanism, when assembling the tool rest. Since there is no need to adjust the preload on the bearing body and the number of parts is small, there is an effect that the work efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view of a main part of a turning and indexing device according to the present invention.

FIG. 2 is a vertical cross-sectional front view of essential parts showing a conventional turning and indexing device.

FIG. 3 is a vertical sectional front view of a main part showing another example of a conventional swivel indexing device.

[Explanation of symbols]

 1 Turret head (revolving structure) 2 Indexing shaft 3 Turret body (fixed base) 4 Cylindrical shaft part 6 3-piece coupling 7 Stationary side indexing coupling 8 Turning side indexing coupling 9 Fixed indexing coupling 10 Hydraulic cylinder 11 Piston 12 Turret 20 Bearings 21, 22 V-shaped annular groove

Claims (2)

[Claims] 1. A stationary side indexing coupling fixed to a fixed base, a swivel side indexing coupling fixed to a revolving body and concentric with the stationary side indexing coupling, and A three-piece coupling having a fixing index coupling that meshes with both couplings at the same time, and the fixing index coupling moves in the axial direction of the revolving structure to engage and disengage the both couplings. In the swivel indexing device, the swivel body is rotatably supported by the fixed base with a bearing body interposed between the stationary side index coupling and the swivel side index coupling. Characterized by 3
Swivel indexing device using piece coupling. 2. The swivel using a three-piece coupling according to claim 1, wherein the stationary side index coupling and the swivel side index coupling are integrally formed with an inner ring and an outer ring of the bearing body. Indexing device.