| 摘要 |
1,044,876. Hydraulic apparatus. CLAYTON DEWANDRE CO. Ltd. May 19, 1965 [May 22, 1964], No. 21230/64. Heading F1P. [Also in Division F4] In a vehicle ventilation system a fan either passes air over an engine coolant heat exchanger into the vehicle or withdraws air from the vehicle over the heat exchanger according to the temperature inside the vehicle. As illustrated, fans 9, driven by oil operated hydraulic motors 10, are associated with two heat exchangers 1 and 2, Fig. 1 (not shown), connected in series or parallel in the coolant circuit of a water cooled engine of a double deck vehicle and replacing the normal radiator. The oil circuit for driving the motors 10 comprises a reservoir 12, an engine driven pump 13, a flow reversing valve 15 and a motor by-pass controlled by a valve 7. The valve 7 is operated by a thermostat 6 in an engine coolant pipe 5 and acts to increase the fan speed as the coolant temperature rises and vice versa. A relief valve 14 is provided to prevent excess oil pressure building up. The fans 9 and their heat exchangers are located in ducts 22 having openings 31 leading to the vehicle, Figs. 3 and 4 (not shown), which is also provided with roof ventilators 23. The flow reversing valve 15 is under the control of a vehicle thermostat so that when the vehicle temperature is below a given level the fans operate to pass air over the heat exchangers into the vehicle, and when the vehicle temperature is above the given level the fans operate to withdraw air from the vehicle over the heat exchangers. An additional fan 28 is provided to give a positive pressure in the vehicle when the fans 9 are acting as extractors, a one-way bypass 30 providing automatic control according to the direction of oil flow. An additional electric pump 24 is provided to drive the fans when the vehicle is at rest, a one way valve 27 preventing reverse flow through the pump 13 and a one way valve 26 preventing bypassing of the motors 10 under normal operation when the valve 7 is closed. Oil filters 19 and a cooler 20 are provided. The additional fan 28 and pump 24 may be omitted. The hydraulic motors 10 may be replaced by electric motors. |
