| 摘要 |
1500767 Fluid dampers; valves GKN STENMAN AB 16 June 1975 [20 June 1974] 25630/75 Headings F2S and F2V [Also in Divisions E1-E2] In a door closing device a casing 2 houses a pinion 3, co-operating with a door actuating member, engaged with a rack 6c on a piston 6 slidable in a cylinder 5 against the action of a spring 9, the wall of the cylinder 5 having a channel 11 connecting opposite ends of the piston so that during movement of the piston 6 fluid flows through the channel 11 to an opposite end of the cylinder through a constricted passage formed in a valve member 31 provided with a piston member 30 which is movable against a spring 16 to limit the fluid flow through the channel 11 when the fluid pressure has built up during the door opening operation so as to form a damping means to damp the movement. Fig. 2 illustrates the position of the various parts of the device when the door closure is being delayed. Fig. 4 illustrates the position of the various parts of the device when the door subjected to a high speed opening action. During this latter action a spring-loaded safety valve member 33 comes into operation. In operation, when the door is opened, the piston 6 is displaced to the left against the force of the spring 9 and oil in the left hand end of the cylinder 5 is forced through a branch channel 11d, the main portion of the channel 11 and the branch channels 11b and 11a to the right hand end of the cylinder 5. At the same time the branch channel 11d short circuits the constricted passage 15 until the portion 6b of the piston closes the branch channel 11d such that the oil is forced to flow through the branch channel 11c and past the parts of valve members 31. A valve screw 12 is provided at the opposite end of the channel 11 which can be turned to control and damp the flow of oil through the branch channels 11a and 11b. |
