JPS6094257A - Turntable indexing apparatus - Google Patents

Abstract

PURPOSE:To permit the indexing with high accuracy by supporting a turntable under a static pressure onto a fixed board and conneting said turntable onto a driving shaft through a flexible coupling and preventing the transmission of the vibration of a breading for supporting the driving shaft, onto the turntable. CONSTITUTION:A turntable 2 is supported under a static pressure in the thrust and radial directions onto a fixed board 1 by a bearing member 3. Said turntable 2 is connected through a flexible coupling 6 to the upper edge of a driving shaft 4 rotatably supported through a bearing 5 onto the fixed board 1. A revolution detector 7 is fixed onto the fixed board 1 so as to be arranged on the revolution center line of the turntable 2, and the input shaft 8 of the revolution detector 7 and the turntable 2 are conneected through a center connecting shaft 9 which is rotatably inserted into the center of the driving shaft 4 and a flexible coupling 10. Therefore, the transmission of the vibration of the bearing 5 and the force by the driving apparatus onto the turntable 2 is prevented, and the indexing with high accuracy is permitted.

Description

DETAILED DESCRIPTION OF THE INVENTION <Technical Field> The present invention relates to a rotary table indexing device for a workpiece processing machine.

<Prior Art> Rotary tables are often used in machining centers and the like to index workpieces.

However, in conventional devices, the drive shaft is rotatably supported on a fixed base, and the rotary table is integrally connected to the rotary table. Unable to index rotation.

By the way, an ultra-precision processing machine that processes curved surfaces such as spherical surfaces and parabolic surfaces by controlling the cutting tool to face perpendicular to the processing surface requires high precision indexing of the tip of the cutting tool. reactor. In this case, when the above conventional device is applied to index the cutting tool,
The above requirements are not satisfied, and there is a problem that errors in the shape of the machined surface occur.

<Objective of the Invention> The object of the present invention is to reduce the run-out of the bearing supporting the drive shaft,
The problem is that vibrations and even radial force from the drive device are not transmitted to the rotary table (in this way, the rotary table can be indexed with high precision).

<Configuration of the Invention> The configuration of the present invention is such that the rotary table is statically supported by the guide portion of the fixed base, and is connected to the drive shaft rotatably supported by the fixed base via a flexible coupling Z, and the rotating table is connected to the drive shaft rotatably supported by the fixed base. This is a device that connects a drive device.

Furthermore, in addition to the above configuration, the present invention provides a rotation detector arranged on the rotation center line of the rotation table, and a central connection shaft passing through the center of the drive shaft between the input shaft of the rotation detector and the rotation table. They are also connected via a flexible coupling 7.

<Examples> Examples of the present invention will be described below with reference to the accompanying drawings. 1st
In the figure and FIG. 2, 1 is a fixed base. A rotary table 2 is supported on this fixed base 1 by bearing members 3 under static pressure in the thrust and radial directions. The bearing member 3 has an annular shape, and well-known bearing pockets are formed on the inner circumferential surface and upper and lower end surfaces thereof. Reference numeral 4 denotes a drive shaft rotatably supported on the fixed base 1 via a bearing 5.

The upper end of this drive shaft 4 and the rotary table 2 are connected via a flexible coupling 6. A worm wheel 11 is provided on the drive shaft 4, and a worm 12 on a worm shaft 13 rotatably supported on the fixed base 1 meshes with the worm wheel 11. The worm shaft 13 is connected to the output shaft of a drive motor 14 attached to the fixed base 1.

Furthermore, the rotation detector 7 is
A central connecting shaft 9 and a flexible coupling 6 are fixed to a fixed base 1 arranged on a line, and rotatably insert the rotation detector 70 input shaft 8 and the rotary table 2 through the center of the drive shaft 4. They are connected through Kaoru.

Incidentally, the upper end of the central connecting shaft 9 is integrally connected to the rotary table 2 by a well-known connecting means such as a seapan ring.

Since the present invention has the configuration as described above, the drive motor 14
The rotational power of worm 12, worm wheel IIY
It is transmitted to the drive shaft 4 via the drive shaft 4, and further transmitted from the drive shaft 4 to the rotary table 2 supported by static pressure via the flexible coupling 6, where it is indexed and rotated.

In addition, the rotation angle of the rotary table 20 is detected by the central connecting shaft 9.
The rotational speed is transmitted to the input shaft 8 of the rotation detector 70 via the flexible coupling 10 and detected.

<Other Embodiments> The joints connecting the rotary table 2 and the drive shaft 4, and the central connecting shaft 9 and the rotation detector 70 may be plate springs, as long as they have a structure that can be floated in two directions. It is possible to apply well-known joints that utilize static pressure slides, etc.

<Effects> According to the present invention, since the rotary table is supported by static pressure on the fixed base, rotation accuracy is high, misalignment and runout are small, and errors in the indexing position are minimised. In addition, since the drive shaft and the rotary table are connected via a flexible coupling in a power transmission configuration, runout, vibration, etc. of the bearings that support the drive shaft are not transmitted to the rotary table.

Furthermore, the rotation angle detection mechanism of the rotary table includes a central connection shaft and a flexible coupling that connect the input shaft of a rotation detector placed on the rotation center line of the rotary table and the rotary table through the center 7 of the drive shaft. Because they are connected via Z, they are concentrically arranged and compact, and the rotation accuracy is not affected by misalignment of the rotation detector.
Further, the rotation transmission mechanism between the rotary table and the rotation detector has no inclusions such as gears, which has the advantage of greatly improving detection accuracy.

[Brief Description of the Drawings] Fig. 1 is a sectional view of the device of the present invention, and Fig. 2 is a cross-sectional view taken along n-n of Fig. 1.
FIG. 1...Fixed base, 2111111 rotary table, 3...
・Bearing part removed, 4...Fist drive shaft, 6...ψ flexible coupling, 7...Rotation detector, 8...Input shaft, 9
. . . Middle Ib connection shaft, 10. Flexible coupling, 11. Fist worm wheel, 12. Worm, 13. Drive motor.

Claims (2)

[Claims] (1) The rotary table is supported by static pressure on the protrusion of the fixed base, and connected via a flexible coupling to a drive shaft rotatably supported on the fixed base, and a drive device is connected to the drive shaft. A rotary table indexing device featuring: (2) The rotary table is statically supported by the guide part of the fixed base, rotatably supported by the fixed base, and connected to one drive shaft via a flexible coupling, and the drive shaft drive shaft device described in fitJ is connected, Further, a rotation detector is disposed at the center of rotation of the rotary table, and the input shaft of the rotation detector and the rotary table are connected to the center of the drive shaft.
A rotary table indexing device characterized in that it is connected via a central connecting shaft and a flexible coupling.