Valve Controller, Valve Controlling Method, Refrigeration And Cold Storage System, Device And Method For Controlling The System

Abstract

To provide a motor-driven valve with a small number of parts, with excellent assemblage, capable of maintaining a large valve port diameter even downsized, and to prevent deterioration of housing environment due to sound caused by the impact and shortened life that are generated by collisions of closing limit stopper parts. A motor-driven valve according to the present invention comprises: a male screw member rotating in accordance with a rotation of a rotor of an electric motor and engaging with a female screw member fixed to a valve main body; a valve body contacting to and separating from a valve seat in the valve main body by a rotation of the male screw member; two stopper parts rotating in accordance with the rotation of the rotor of the electric motor; an opening limit stopper part mounted to the female screw member, the opening limit stopper part contacting with one of the two stopper parts in a fully-opened state of the motor-driven valve to restrict the rotation of the male screw member in a direction that the motor-driven valve opens; and a closing limit stopper part mounted to the female screw member, the closing limit stopper part contacting with another stopper part in a fully-closed state of the motor-driven valve to restrict the rotation of the male screw member in a direction that the motor-driven valve closes.

1 - 19 . (canceled) 
     
     
         20 . A controller for controlling operation of a refrigeration cycle, said refrigeration cycle having temperature sensors for separately detecting a temperature of a refrigerant at inlet and outlet of an evaporator, said controller controlling said operation by controlling a valve opening of a motor-driven valve based on a detected value of each temperature sensor to control flow rate of the refrigerant, said controller comprising:
 valve opening setting means for performing one of setting and changing an emergency valve opening of the motor-driven valve to an intermediate valve opening between a fully-closed state and a fully-opened state; and   valve opening controlling means for stopping, when an abnormality occurs in at least one of the sensors, movement of the motor-driven valve at the emergency valve opening to which one of the setting and the changing is performed through the valve opening setting means, wherein the movement of the motor-driven valve is stopped at the emergency valve opening and operation of the refrigeration cycle is continued.