| 摘要 |
451,654. Stands; hydraulic jacks. KODAK, Ltd., and BUCKSTONE, W., Kodak House, Kingsway, London. Feb. 4, 1935, No. 3549. [Class 52 (v)] An adjustable stand of the pedestal or pillar type supported by a tripod or other base B has the lower part formed as a hydraulic cylinder A in which the hollow upper part C slides as a piston, a valve E being provided in the piston, normally held closed by the liquid pressure beneath the piston assisted by a spring M<1>, the arrangement being such that when the upper member and its load are manually lifted the valve opens and liquid flows from the hollow upper member into the cylinder, and on release of the upper member the valve closes and the upper member is retained at the height to which it has been raised. To lower, the valve E is opened by depressing a push-button E4 and the area of the valve is preferably such that the weight must be manually supported or eased before the valve can be opened. The collapsable base comprises a triangular plate B to which are pivoted legs B<1> connected by links B<2> to a collar B<3> slidable on the cylinder A. The upper part C is provided with cup leathers C<5>, C<6> and complete withdrawal is prevented by a flange H. The rod E<3> of the valve E carries a further valve E<5> controlling a breather port E<8> allowing exit of air as the stand is lowered and preventing escape of liquid if the stand is laid horizontally or inverted. Brackets F, G for the articles supported, e.g. a camera and a lamp are adjustably mounted on the part C. In a modification the valve E is replaced by a ball valve. Reference has been directed by the Comptroller to Specifications 10052 /86, [Class 52], 28456 /06, [Class 78], and 14938/10, [Class 80 (iii)]. |
