Patent GB-303156-A (GB)
Title: Improvement in elevator door control system
IPC: B66B13/12
Filed: 1928-12-20
Abstract: 303,156. Waygood-Otis, Ltd., (Assignees of Brady, T.). Dec. 30, 1927, [Convention date]. Operating doors electrically and by springs; checks.-A shaft door of a lift well is opened by a motor mountd upon the lift cage, a spring device also mounted upon the cage being provided to move the door to the closed position. The motor and spring device are also in operative engagement with the gate of the lift cage for respectively opening and closing it. The lift cage 10 carries an electric motor 60, Figs. 1 and 2, mounted above the collapsable cage door 13, the motor being connected by a chain 64 and sprocket wheels to a shaft 45, and a length of chain 57 that runs over sprocket wheel 46 and a pulley 54 is connected to a plate 41 of a carriage 36. The plate 41 is connected through links 72, 73, yoke arm 74, and link 75 to a rocking arm 76, and this arm is connected in turn to a door closing device and check shown in Fig. 6, and to the device shown in Fig. 7, which operates to check the doors when they are moved to the open position. The carriage 36 is connected to the cage door 13 by means of a lever 153 that is pivotally mounted on the lower end of shoes 42 of the carriage and is adapted to engage with a pin 155, as shown in Fig. 2. The door 14 of the lift well is normally secured in the closed position by toggle levers 171, 170, of which the lever 171 is connected to a switch member 177, 178, and the lever is connected through links and levers with a rod 160. This rod is attached to the lower end of a lever 156 carrying a roller 157, and is provided with springs 166, 167 centered about an abutment 165. The door closing and check device comprises cylinders 67 each containing a spring 113, Fig. 6, the tensions of which is adjustable by altering the position of the sleeve 107 relative to the rod 104, the check comprising a piston 115 on the rod 104 movable in the cylinder 105. The piston has a one-way ball valve 121 in a passage 118, the check liquid passing freely through the passage 118 and grooves 128 when the piston moves upwardly, and through the restricted passage 123 when the piston is moving towards the lower end of the cylinder. The check shown in Fig. 7, for cushioning the opening movement of the doors, comprises a piston 135 in a cylinder 136, with a one-way passage 140 in the piston, a bye-pass 144, and a connection between the piston rod 100 and the yoke 76. In operation, the gate 13 and door 14 are normally closed, the gate being latched to the carriage 36 and the door being secured by the straightened arms 170, 171. The carriage is held in the position shown in Fig. 2 by the springs 113. When the lift cage 10 is stopped opposite a shaft door 14 the shoe 42 embraces the roller 157. To open the gate and door, the motor 60 is energized to cause the sprocket 46 to move the carriage along its guide rails 31, 32. The initial movement of the carriage causes a movement of the roller 157 relative to the door 14 to break the straight-line position of the levers 170, 171 through the rod 160 and connecting linkwork. As the carriage moves the gate and door to the opened position the arms and links 72 - - 76 move the rods 104 to extend the closing springs 113, and the .check piston 135 cushions the opening movement. To close the door and gate the motor is de-eneigized. The action of the springs 113 on the rods 104 and connecting links returns the carriage 36, the arms 170, 171 by moving into the horizontal position securing the door 14 in the closed position, and the check piston cushioning the gate and door closing movement. To prevent the door from being moved by an opening movement after it has been moved in a closing direction, it is provided with a pawl 181 to engage a rack 182 with a projection 183. A two-speed door and operating mechanism therefor is also described.