DE3023233C2 - Pressure medium distributor for rotating clamping cylinders with clamping pistons that can be axially displaced therein on machine tools, in particular multi-spindle lathes - Google Patents

Description

The invention relates to a pressure medium distributor for revolving, double-acting clamping cylinders for actuating clamping devices on machine tools, in particular multi-spindle lathes of the type reproduced in the generic term of claim 1.

Pressure medium distributors of this type are known from DE-GM 79 32 853, for example. With them it will because of the high speed of the clamping cylinder through the between the distributor shaft and the distributor housing existing annular gap inevitably escaping leakage oil collected in chambers and through a additional connection returned to the pressure medium tank. The one for the additional leakage oil return lines The effort required is particularly important in the case of multi-spindle lathes, since the Leak oil from all pressure medium distributors through a central distributor that switches with the spindle drum into the Container must be returned.

The object of the invention is to provide a pressure medium distributor as described in the preamble of claim 1 Art to be designed in such a way that a special leakage oil connection is not required on the distributor housing.

This object is achieved by the features of the characterizing part of claim 1.

Another embodiment of the invention according to claim 2 has the advantage that when penetrating Leak oil in one of the leak oil collecting chambers in the ring channel assigned to it there is no overpressure

An embodiment of the invention is at hand

the drawing, which is connected to a rotating, double-acting clamping cylinder Pressure medium distributor shows in longitudinal section, described below.

In the clamping cylinder 1, a double-acting clamping piston 2 is axially displaceable in a known manner The distributor shaft 3 is arranged on the end face of the clamping cylinder 1 facing away from the clamping device of a pressure medium distributor, the distributor housing 4 of which is arranged in a stationary manner. The distributor housing 4 has two connections 5 and 6 for pressure medium lines. These connections 5 and 6 open into ring channels 7 and 8 of the distributor housing 4. In the distributor shaft 3, two pressure medium channels 9 and 10 are provided, whose Openings are in the area of the annular channels 7 and 8 and a supply or discharge of the pressure medium in which allow or from the cylinder chambers 11 and 12 of the clamping cylinder 1.

In the distributor housing 4 are also two at a distance from the opposite side surfaces of the Ring channels 7 and 8 arranged collecting chambers 13 and 14 for the from the through between the Distributor shaft 3 and the bore of the distributor housing 4 existing column inevitably emerging Leak oil provided.

According to the invention, from the leak oil collecting chamber 13 facing away from the clamping cylinder 1, a Longitudinal bore 15 to the annular channel 8 and from the leakage oil collecting chamber adjacent to the clamping cylinder 1

14 from a longitudinal bore 16 to the annular channel 7. The bores 15 and 16 are in the vicinity of theirs Annular channel 8 or 7 facing end equipped with a check valve 17 or 18, which is in the illustrated embodiment each from a constantly under the action of a weakly biased There is a helical compression spring standing ball and opens to the annular channel 8 or 7.

As can be seen from the drawing, each leak oil collecting chamber 13 or 14 stands through the bore

15 or 16 in connection with the ring channel 8 or 7 furthest away from it. That way will each of the leak oil collecting chamber 13 or 14 collected leak oil whose through the bore 15 or 16 associated ring channel 8 or 7 is free of excess pressure.

The leakage oil penetrating alternately into the leakage oil collecting chambers 13 and 14 can pass through the bore 15 or 16, the check valve 17 or 18 and the overpressure-free annular channel 8 or 7 in the pressure medium container flow back. In the leakage oil collecting chambers 13 and 14, therefore, there can be no significant Build up overpressure so that to seal the leakage oil collecting chambers 13 and 14 to the outside elastic sealing means 19 and 20 are sufficient.

1 sheet of drawings

Claims (2)

Patent claims: 1. Pressure medium distributor for rotating, double-acting clamping cylinders for actuating clamping devices on machine tools, in particular multi-spindle lathes, whose distributor shaft, which is firmly connected to the clamping cylinder and provided with two pressure medium channels, is enclosed by a stationary distributor housing, which has an annular channel in the area of the mouth of each pressure medium channel and in the Area of each ring channel has a connection for a pressure medium line and is formed with two leak oil collecting chambers arranged at a distance from the side surfaces of the ring channels facing away from one another, characterized in that each of the leak oil collecting chambers (13 and 14) is provided with a bore (15 or 16 ) is in communication with one of the ring channels (8 or '/), and that each of the two bores (15 and 16) is connected to a check valve (17 or 18) which opens towards the ring channel (8 or 7) assigned to it. Is provided. 2. Pressure medium distributor according to claim 1, characterized in that each leak oil collecting chamber (13 or 14) through the hole (15 or 16) with the annular channel furthest away from it (8 or 7) communicates.