| 摘要 |
1,027,295. Hydraulic jacks. COMPAGNIE FRANCAISE THOMSON-HOUSTON. May 17, 1963 [May 17, 1962], No. 19737/63. Heading B8J. A structure which may be used for supporting a turret assembly, e.g. a radar antenna, comprises a pedestal frame 1 mounted on three hydraulically operated leg assemblies L1, L2, L3. Each of the assemblies has a load-transmitting spherical member 3, 6, the member of assembly L1 being fixed to a base 58, that of assembly L2 being displaceable towards and away from the fixed member 36, and the member 36 of assembly L3 being displaceable in a horizontal plane. The method of supporting the assemblies L2, L3 allows for differential thermal expansion between the frame 1 and a bed plate 38 anchored in a concrete footing 39. Leg assembly L3 (Fig. 3).- A casing 5 contains a plunger 4 having two surfaces 6, 7 which slidingly engage the bore of the casing. A longitudinal flat area 8 on the plunger is engageable by hydraulic presser members 10 which, by means of a hand pump 14 and a selector valve 57, may exert a lateral force on the plunger for blocking the latter in the casing 5. An actuator cylinder 17 in the upper part of the casing has a piston 16 attached to the plunger 4. A valve 56, in its neutral position, blocks off chambers 20, 21 in the cylinder 17 and locks the piston 16. Operation of the pump 14 and the valve 56 from its neutral position to one side causes the casing 5 to move upwards. With the valve displaced to the reverse position, the casing 5 moves downwards under gravity. Fine vertical adjustment of the casing is provided for by a rod 24 which extends into the fluid chamber 21 of the cylinder 17. A hand wheel 25 is secured to a threaded rod 27 engaging a sleeve 29 to which the rod 24 is attached. Rotation of the hand wheel causes more or less penetration of the rod into the chamber 21 for sensitive adjustment of pressure in the chamber. A revolution counter device 32 is operated by the hand wheel. To permit the load-transmitting member 36 to shift over a supporting surface 40 of a base member 37 and to thus avoid stress due to thermal expansion, the loading on the surface 40 by the member 36 may be reduced by a piston 44 which engages a link 43 having a ball-shaped upper end seated in a socket portion of the member 36. The piston 44 is movable by a foot pump 50, 61. Leg assemblies L1, L2.-These differ from assembly L3 only in the construction and support of the members 36. In L2, Fig. 2, the member 36 has machined sides and slides within a groove formed in the top of a base 59. The member 36 of L1 is fixed. |
