| 摘要 |
1,052,624. Electrical speed regulating of rail trucks. SIEMAG MASCHINENUND STAHLBAU NETPHEN G.m.b.H. June 21, 1963 [June 22, 1962], No. 24710/63. Heading B7L. Electrical speed regulating apparatus for rail trucks 2 comprises an electric motor 9 pivoted at 10 to support block 7 and biased by spring 11 to engage a friction pulley 16 on shaft 12 with a passing truck to accelerate or brake the truck depending on the speed and direction of rotation of motor 9. The pulley 15 comprises a friction ring 20 surrounding pulley 15 with a clearance and held on the pulley by removable plates 17, 18. A support roller 6 prevents a truck from toppling when engaged by pulley 15, 20. The motor 9 has, in every obtainable torque range, a maximum torque at or about zero revolutions and can also be stalled whilst current is flowing. In Fig. 6, not shown, the pulley is driven through a reduction gearing and spring 11 is replaced by a piston cylinder pressurized by a pump device actuated by a passing truck. In operation, a truck closes a contact 25, Figs. 1, 7, not shown, to energize a time relay 28, a second contact 26 being positioned behind the contact 25 so that relay 28 is still energized to close a switch 28a when contact 26 is closed if the truck is exceeding a predetermined speed. When this happens a contactor 29 is energized to close contacts 30 to drive motor 9 counter to the direction of truck travel to brake the truck; a centrifugal switch reverses the motor when a predetermined speed has been reached. If the truck is not exceeding the predetermined speed then, relay 28 opens switch 28a, as shown, before contact 26 is operated to energize contactor 31 to close contacts 32 to drive motor 9 in the direction of travel of the truck to accelerate the truck; self-holding contacts 33, 34 keep contactors 29, 31 energized until a contact 35 is depressed by a truck leaving the regulating apparatus. Several pulleys may be driven from the same motor. A weight-detecting apparatus may set the motor 9 for one of three different torque ranges depending on the weight of the truck. |
