| 摘要 |
<p>1,028,449. Air conditioning. HONEYWELL Inc. Feb. 24, 1965 [Feb. 28, 1964], No. 7957/65. Heading F4V. [Also in Division G3] A pneumatic actuator 14 comprises a diaphragm 55, Fig. 2, which is moved against a spring loading by a control pressure fed to a chamber 60 through an inlet 15 and passages 62, 61. The chamber 60 is also connected through a passage 64 to a chamber 70 on one side of a diaphragm 54 which diaphragm carries a valve closure 72 to control the flow through the passage 64. A connection 31 leads to the chamber 70 while a connection 30 leads to a chamber 80 on the opposite side of the diaphragm. In operation, with the valve 72 open, the diaphragm is not actuated by the control pressure since this pressure flows to the outlet 31. When the pressure differential between the chambers 80, 70 is sufficient to close the valve 72, the diaphragm is then positioned in response to the control pressure. The actuator 14 is used to control dampers 41, 42, Fig. 1 (not shown), in a heating and ventilating system in which the control pressure is supplied in response to a thermostat 11 and the actuator is only responsive to this pressure when a blower is operative to provide the pressure differential to close the valve 72. The control pressure fed to the actuator inlet 15 also passes directly to an outlet 16 connected by a conduit 17 to an actuator 21 which controls a valve 22, this valve controls the flow of heating/cooling medium to a heat exchanger 24. The conduit 17 is also connected to a low temperature thermostat 25. In a modification of the actuator, the valve 72 is carried on a leaf-spring actuated by the diaphragm 55.</p> |
