Rotary indexing table having a direct drive of the transport cam

Abstract

A rotary index table comprising a plate, which has drivers that engage with a drive groove of a cam barrel, wherein the plate can be driven by the cam barrel to carry out a rotational movement about a rotational axis which in turn can be driven by a motor to carry out a rotational movement about the longitudinal axis thereof, and wherein the motor directly drives the cam barrel.

Claims

1. A rotary indexing table having a plate which has drivers engaging into a driving groove of a barrel cam, wherein the plate is driven via the barrel cam to make a rotary movement about an axis of rotation which is in turn driven by a torque motor to make a rotational movement about its longitudinal axis, wherein the torque motor comprises magnets that cooperate with corresponding coils to generate a driving force to directly drive the barrel cam without a transmission, the barrel cam has a prolongation which has a same outer diameter as that of the barrel cam and the magnets of the torque motor are disposed on the prolongation of the barrel cam, and the prolongation and the barrel cam are unitary components.

2. A rotary indexing table in accordance with claim 1, wherein the barrel cam and the motor are coaxially arranged.

3. A rotary indexing table in accordance with claim 1, wherein the motor is an asynchronous motor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be described in the following purely by way of example with reference to advantageous embodiments and to the drawings. There are shown:

(2) FIG. 1 a schematic view of an embodiment of a rotary indexing table in accordance with the invention from above; and

(3) FIG. 2 a cross-section through a further embodiment of a rotary indexing table in accordance with the invention.

DETAILED DESCRIPTION

(4) FIG. 1 schematically shows a rotary indexing table 10 which has a turntable 12 on which workpieces can be spanned for machining and/or assembly. The turntable 12 is driven by a barrel cam 14 to make a rotational movement about an axis of rotation R which extends perpendicular to the plane of the Figure. To transmit a drive movement of the barrel cam 14, which is a rotation of the barrel cam 14 about an axis of rotation R perpendicular to the axis of rotation R, onto the turntable 12, the latter has drivers (not shown in FIG. 1) which engage in a form known per se into a driving groove (not shown in FIG. 1) having a constant or varying pitch and running spirally about the barrel cam 14.

(5) The barrel cam 14 is rotationally fixedly connected to a drive shaft 16. The drive shaft 16 is simultaneously the output shaft of a motor 18 which is, for example, electrically driven.

(6) In the rotary indexing table 10, the barrel cam 14 and the motor 18 are arranged coaxially, i.e. both the motor 18 and the drive shaft 16 as well as the barrel cam 14 rotate about the common axis of rotation R in operation.

(7) It can be seen from FIG. 1 that the drive of the barrel cam 14 takes place in a direct manner, i.e. without a transmission interposed between the motor 18 and the barrel cam 14. Only the drive shaft 16 is provided to transmit a driving torque between the two named components.

(8) In principle any motoralso of a non-electric constructioncan be used as the motor 18, such as asynchronous motors or synchronous motors.

(9) FIG. 2 shows a cross-section through a further embodiment 10 of the rotary indexing table. It can be recognized in the left hand part of the drawing how a driver 20 of the turntable 12 engages into a driving groove 22 of the barrel cam 14. The representation of this known drive concept is only shown in highly simplified form.

(10) The right hand part of FIG. 2 comprises the drive components of the barrel cam 14. In contrast to the embodiment shown in FIG. 1, the drive of the rotary indexing table 10 has no drive shaft 16. The barrel cam 14 rather itself forms a part of the motor 18 which is made as a torque motor. The barrel cam 14 has (electric) magnets 24 at an extension section A which cooperate with coils 26 of the torque motor 18. In other words, the extension section A is the rotor of the torque motor 18 which is directly connected to a section B of the barrel cam 14 having the driving groove 22. The sections A, B are consequently integral components of the barrel cam 14. The section B of the barrel cam 14 can also be calledrelative to the extension section Aan extension of the rotor of the torque motor 18. The extension section A has substantially the same diameter as the section B of the barrel cam 14 provided with the driving groove 22.

(11) The embodiment of the drive of the rotary indexing table 10 shown schematically in FIG. 2 is characterized by a compact construction and a precise drive of the barrel cam 14. Expensive transmission elements suffering from friction/clearance are not used.

REFERENCE NUMERAL LIST

(12) 10, 10 rotary indexing table 12 turntable 14 barrel cam 16 drive shaft 18 motor 18 torque motor 20 driver 22 driving groove 24 magnet 26 coil R, R axis of rotation A extension section B groove section