Hydrostatic bearing for supporting a telescope

Abstract

The present invention relates to a hydrostatic bearing providing a foot part supporting a load-carrying unit, a head part, and body part forming a lower chamber and an upper chamber. A lower member is supported by the load-carrying unit and arranged inside the lower chamber. An upper member is controllable by a pressurizing fluid and arranged inside the upper chamber. The lower member is controllably moveable along a central axis of the hydrostatic bearing between a retracted state. The lower member is distanced from the upper member, and an extended state. The lower member is also in contact with the upper member. The hydrostatic bearing acts both as a conventional slave bearing and a conventional master bearing.

1 . A hydrostatic bearing for supporting a telescope comprising:
 a foot part supporting a load-carrying unit,   a head part having a first surface adapted to receive an external load (W) and a second surface opposite to the first surface,   a body part arranged in between the foot part and the head part, the body part forming a lower chamber and an upper chamber, the upper chamber being provided with an inlet for a pressurizing fluid,   a lower member supportable by the load-carrying unit and arranged inside the lower chamber, the lower member providing a first end surface facing away from the load-carrying unit and a second end surface facing the load-carrying unit,   an upper member controllable by the pressurizing fluid and arranged inside the upper chamber, the upper member providing a first end surface facing the second surface of the head part and a second end surface facing the first end surface of the lower member, wherein   the lower member is controllably moveable along a central axis (A) between a retracted state, where the first end surface of the lower member is distanced from the second end surface of the upper member, and an extended state, and wherein   the first end surface of the lower member is in contact with the second end surface of the upper member.   
     
     
         2 . The hydrostatic bearing according to  claim 1 , wherein the lower member comprises a lower hydraulic piston compressing the load-carrying unit when the lower member is in its retracted state. 
     
     
         3 . The hydrostatic bearing according to  claim 1 , wherein the upper member comprises an upper hydraulic piston supporting the applied external load when the lower member is in its retracted state. 
     
     
         4 . The hydrostatic bearing according to  claim 1 , wherein the head part further comprises a main recess for lubricating fluid being arranged on the first surface of the head part. 
     
     
         5 . The hydrostatic bearing according to  claim 4 , further comprising a pump for supplying lubricating fluid to the main recess. 
     
     
         6 . The hydrostatic bearing according to  claim 5 , wherein the pump is arranged in the head part. 
     
     
         7 . The hydrostatic bearing according to  claim 1 , wherein the head part further comprises at least one sub-recess being connected to the main recess via a flow restrictor for adjusting a flow of lubricating fluid between the main recess and the at least one sub-recess, wherein the at least one sub-recess also is arranged on the first surface of the head part. 
     
     
         8 . The hydrostatic bearing according to  claim 7 , wherein the head part comprises four sub-recesses being symmetrically arranged about the main recess. 
     
     
         9 . The hydrostatic bearing according to  claim 1 , wherein the lower chamber also is provided with an inlet for a pressurizing fluid. 
     
     
         10 . The hydrostatic bearing according to  claim 9 , wherein the inlet for a pressurizing fluid of the lower chamber is fluidly connected to the inlet for a pressurizing fluid of the upper chamber. 
     
     
         11 . The hydrostatic bearing according to  claim 1 , wherein the load-carrying unit consists of at least one of mechanical springs and an electro-mechanical actuator. 
     
     
         12 . A telescope arrangement comprising:
 at least one hydrostatic bearing having a foot part supporting a load-carrying unit,
 a head part having a first surface adapted to receive an external load (W) and a second surface opposite to the first surface, 
 a body part arranged in between the foot part and the head part, the body part forming a lower chamber and an upper chamber, the upper chamber being provided with an inlet for a pressurizing fluid, 
 a lower member supportable by the load-carrying unit and arranged inside the lower chamber, the lower member providing a first end surface facing away from the load-carrying unit and a second end surface facing the load-carrying unit, 
 an upper member controllable by the pressurizing fluid and arranged inside the upper chamber, the upper member providing a first end surface facing the second surface of the head part and a second end surface facing the first end surface of the lower member, wherein 
 the lower member is controllably moveable along a central axis (A) between a retracted state, where the first end surface of the lower member is distanced from the second end surface of the upper member, and an extended state, and wherein 
 the first end surface of the lower member is in contact with the second end surface of the upper member.