| 摘要 |
348,583. Operating gates. ALEXANDER, E. M., of Mortimer's, Milton, Northampton. Feb. 13, 1930, No. 4924. [Classes 44 and 65 (i).] A pair of inclined tracks 12, 12a, Fig. 2, are fixed at their upper ends to a spindle 14 and at their lower ends to a frame 13. Trolleys carrying tanks 8, 19 run on the tracks 12, 12a respectively, and are connected by cords passing over pulleys 18. A cord 26 supporting a heavy bar 28 passes over a pulley carried by the spindle 14 and is connected to the trolley 19 ; it is of such length that it is taut only when trolley 19 is at or near the lower end of the track 12a. Each tank is provided with an outlet valve 25 which is opened by striking a projection 24 at the lower end of the track and is closed by striking a similar projection at the upper end of the track; the valve consists of pipe 25 which slides in a tube 25<1>, Fig. 3, fixed in the tank, to bring ports 46, 46<1>, into or out of register. When the gate is closed, trolley 19 is at the lower end of its track, trolley 8 at the upper end, both tanks are empty, and bar 28 is raised. When a vehicle stands on either of the treadles 4 a spring-closed valve 1 is opened, and water flows by pipe 6 and a flexible pipe into tank 8, which therefore runs down its track 12 and swings the frame 13 to the position shown, thus pulling rod 35 to unlatch and open the gate; trolley 19 is pulled up, and bar 28 is lowered to engage with catches 31 to prevent oscillation of the frame. The swinging of the frame also opens a valve 34, by means of a lever 32 which works in guides on the frame, and admits water by pipe 21 and a flexible pipe to the tank 19. When tank 8 reaches the bottom of its travel it commences to empty, while tank 19 is filling. After an interval, determined by the rates of inlet and outlet of water in the two tanks, tank 19 be comes heavier than tank 8 and runs down its track, raising bar 28 clear of the catches 31, swinging the frame 13 back to its original position to close the gate and to close valve 34, and pulling up tank 8. When tank 19 reaches the bottom of its track, it empties, thus restoring the original conditions. Each catch 31 is pivoted to a strap 47, Fig. 4, fixed to the side member of the frame 13, and its upwardly curved engaging part is held normally raised by a tension spring 48, which yields to free the catch if the gate is forcibly closed ; a piece 49 pivoted to the catch 31 prevents the bar 28 from engaging under the catch 31. |
