Electromagnetically driven valve and driving method of the same

Abstract

An electromagnetically driven valve includes a valve element that has a valve stem and moves in reciprocating motion in a direction in which the valve stem extends; a disc that is interlocked with the valve element at a driving end, extending to a pivoting end, from which a central axis extends and around which the disc oscillates; a coil that oscillates the disc; a power supply that supplies electric current to the coil; and an ECU that controls the flow of current from the power supply to the coil. During the initial period of operation of the disc, the ECU controls the current so that it is supplied from the power supply to the coil in cycles, and in accordance with the voltage and temperature, controls the number of current cycles, the cycle length, and the value of the current.

1 . An electromagnetically driven valve that is operated by the combined action of electromagnetic force and elastic force, comprising: 
 a valve element that has a valve stem and moves in reciprocating motion in a direction in which the valve stem extends;    an oscillating member that is interlocked with the valve element at a driving end, extending to a pivoting end, from which a central axis extends, and the oscillating member oscillates around the central axis;    a coil that oscillates the oscillating member;    a power supply that supplies electric current to the coil; and    a control portion that during the initial period of operation controls at least one of a number of cycles, a cycle length, and a value of an electric current provided in cycles to the coil in accordance with the voltage of the power supply that drives the electromagnetically driven valve and temperature.    
   
   
       2 . An electromagnetically driven valve according to  claim 1 , wherein, as the temperature decreases, the control portion increases the value of the electric current that is provided to the coil in cycles during the initial period of operation.  
   
   
       3 . An electromagnetically driven valve according to  claim 1 , wherein, as the temperature decreases, the control portion increases the number of cycles in which electric current is provided to the coil during the initial period of operation.  
   
   
       4 . The electromagnetically driven valve according to  claim 1 , wherein the coil includes an upper coil and a lower coil, and the oscillating member is provided between the upper coil and the lower coil.  
   
   
       5 . An electromagnetically driven valve that is operated by the combined action of electromagnetic force and elastic force, comprising: 
 a valve element that has a valve stem and moves in reciprocating motion in a direction in which the valve stem extends;    an oscillating member that is interlocked with the valve element at a driving end, extending to a pivoting end, from which a central axis extends, and the oscillating member oscillates around the central axis;    a core of an electromagnet that oscillates the oscillating member, and    a permanent magnet that is located on the outer side of the oscillating member and arranged in such a position that magnetic flux passing through the oscillating member and the core becomes greater.    
   
   
       6 . The electromagnetically driven valve according to  claim 5 , wherein the core of the electromagnet includes an upper coil and a lower coil, and the oscillating member is provided between the upper coil and the lower coil.  
   
   
       7 . A method of driving an electromagnetically driven valve that is operated by the combined action of electromagnetic force and elastic force comprising: 
 measuring a voltage of a power supply that drives the electromagnetically driven valve and a temperature; and    controlling at least one of a number of electric current cycles, a cycle length, and a value of electric current provided in cycles to a coil in accordance with the measured voltage and temperature, during the initial period of operation of an oscillating member.