| 摘要 |
1309786 Fluid bearings LUDWIGSBURGER MASCHINENBAU GmbH 23 April 1970 [23 April 1969] 19649/70 Heading F2A [Also in Division B3] A cutting tool 26 mounted in a boring spindle has means to ensure disengagement from the surface being bored by supplying hydraulic fluid to a bearing 28 for the boring spindle so as to effect radial displacement of the spindle. The spindle 14 is supported in two hydrostatic bearing members 28, 28<SP>1</SP> which are fixed in the housing 10 and in which are formed four oil pockets, e.g. 52 spaced equidistantly around the bearing surface of the bearing members 28, 28<SP>1</SP>. Each oil pocket is connected via a throttle valve, e.g. 64 to an hydraulic system 58 so that equal pressure conditions occur in all the oil pockets thus holding the boring spindle in a central position. When the boring operation is completed the angular position of tool 26 is adjusted by a checking device (not shown) so that the tool 26 extends upwards (as in Fig. 1) and the oil pocket 52 which is substantially opposite the tool is opened to low pressure via a two way magnetic valve 70 so that the boring spindle is tilted downwards and the cutting tool released from the surface of the workpiece. In a modification, Fig. 3 (not shown), the spindle is provided with a feed channel (82) which opens out at the surface of the spindle on the same side as the cutting tool 26 and into one of the oil pockets, which one depending upon the angular position of the spindle, and the feed channel (82) is also permanently connected to the hydraulic pressure system 58 by means of an annular groove (90) arranged in an annular projection in the housing 10. Pressure applied via a 2 way magnetic valve (94) and the feed channel (82) will provide extra pressure in one of the oil pockets to remove the cutting tool from the work surface in any angular position. |
