Claims
- 1. A hydraulic pivot drive having a rotary-piston hydraulic cylinder comprising at least two pressure chambers defined by a vane and a radial wall of a cylinder housing and which can be alternatively connected to high-pressure and low-pressure sides of a hydraulic pressure supply system characterized in that control means are provided for leveling out a leak oil loss encountered in a defined rotary position of the vane, a width of gaps remaining between the vane and one of a wall of the cylinder housing or a shaft of the pivot drive and radial partition wall of the cylinder housing are determined in accordance with the following relationship: ##EQU7## wherein: .delta..PHI. is an admissible deviation of the rotary vane from a predetermined desired position, measured in angular degrees,
- .eta. is a viscosity of the hydraulic fluid,
- f.sub.r is a control frequency of the control means,
- .rho. is a difference of the pressures existing in the pressure chambers of the rotary-piston hydraulic cylinder required for maintaining a defined rotary position of the rotary vane,
- G is a geometry factor which considers the gap lengths and widths, and
- a is a sensitivity of the control means determined by a relationship between the maximum pivot angle and a total volume of the pressure chambers, said control means includes a mechano-hydraulic analog controller comprising a follow-up control valve having a spindle drive means for presetting a nominal value and a feedback of the actual value, and in that the nominal value of the pivot angle of the vane can be adjusted by rotating a spindle nut of the spindle drive means by a stepping motor means,
- and in that the control frequency of the control means is at least 500 s.sup.-1, the vane and the partition wall of the housing have a sector-shaped cross-section with a sector angle of 30.degree. and 60.degree., respectively, a diameter of the vane shaft is equal to half a clear diameter of the cylinder housing, a radial and axial extension of the vane are in a range of substantially 18 to 20 mm, and a width of the axially and radially extending gaps between the housing and the vane are identical and substantially equal to 0.05 mm.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3204067 |
Feb 1982 |
DEX |
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Parent Case Info
This is a continuation of Application Ser. No. 463,661 filed Feb. 5, 1983.
US Referenced Citations (8)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2156695 |
May 1973 |
DEX |
Continuations (1)
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Number |
Date |
Country |
Parent |
463661 |
Feb 1983 |
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