| 摘要 |
1368218 Electrically operated sliding doors VEREINIGTE BAUBESCHLAGFABRIKEN GRETSCH & CO GmbH 24 July 1972 14 June 1972 34428/72 Heading E2M A sliding door, in which two leaves 5, 6 are moved on a rail 2 by an electric motor 12 acting via a belt 7 mounted on pulleys 8, 9, is connected to drive a device which, on each opening or closing movement of the door, moves fluid through one of two pairs of series cnnected flow restrictors in a hydraulic circuit, a valve providing a short circuit for one restrictor in each pair for most of the opening or closing but being operated by a door actuated switch to close the short circuit and damp motion toward the limit positions. As shown the pulley 8 is driven by the electric motor and the pulley 9 drives a hydraulic pump 14 which, depending on the direction of motion of the door, forces fluid through flow restrictors 34, 36 or 35, 37. Restrictors 34, 35 are adjustable to vary the normal speed of the door, restrictors 36, 37 provide adjustable damping near the limit positions, and a magnetic valve 42 either blocks or allows passage through lines short-circuiting the latter. Limit switches 64, 67 are actuated by a projection 82 on leaf 5 of the door control the operation of the valve 42; limit switch 62 switches off the motor in the fully open position and reverses its operation after a time delay; and limit switches 65, 63 can be switched in to penform the functions of switches 64, 62 respectively if only partial opening of the door is required. Limit switch 66 prevents operation of the automatic opening mechanism (described below) when the door is fully closed. In modifications a piston and cylinder mechanism replaces the hydraulic pump 14 and a pair of additional flow restrictors (94, 95, Fig. 19 not shown) are placed in parallel with restrictors 36, 37 to replace the valve 42 and are separately switched by devices on the door. The opening flow restrictor is switched for partial opening of the door also but when not required a valve (97) operates to by-pass the opening restrictor. The motor remains on while the doors are closed but a helical spring mechanism (Figs. 4, 5 not shown), driven, by a shaft from the motor, is wound up as the door closes and operates to open the door in the event of a current failure. The doors can be locked in the closed position by an electromagnetically movable latch (Figs. 6, 7 not shown) which is retained by permanent magnets in the locked position until released electromagnetically or by hand. A safety device is provided to stop the doors closing and initiate an opening movement in the event of an obstruction and is operated when a control circuit senses that the interval between pulses emitted in response to door movement exceeds a predetermined value. The preferred form of pulse generator (Fig. 8, not shown) comprises a disc (29) driven by the belt 7 and carrying a number of iron pins (30) which are moved past an inductive device as the disc rotates to cause pulse generation. |
