Method and equipment for treating electrostatic field and electrode used therein

Abstract

A method of treating a food object in an electrostatic field to thaw food rapidly at temperatures between 0° C. and a freezing temperature of an object to be treated. By applying the electrostatic field, the freezing temperature of the food is lowered but the food does not freeze in the electrostatic field. Accordingly, foods are kept fresher longer and the freshness can be maintained over a range of temperatures.

1 . A method of treating an object in an electrostatic field comprising the steps of: 
 setting a conductive electrode in an insulated atmosphere to impress a voltage on the conductive electrode to generate an electrostatic field around the conductive electrode; and    placing an object to be treated in the electrostatic field in an insulated state to perform freezing, thawing, and freshness-keeping of food.    
     
     
         2 . A method according to  claim 1 , wherein the insulated atmosphere is formed with air.  
     
     
         3 . A method according to  claim 1 , wherein the insulated atmosphere is formed with oil.  
     
     
         4 . An apparatus for treating an object in an electrostatic field, which comprises an conductive electrode disposed in an insulated state from an outer environment, and a voltage generating device for impressing a voltage on the conductive electrode.  
     
     
         5 . An apparatus according to  claim 4 , wherein the insulating state is formed with the air, outer environment being formed with a casing of a refrigerator and the like, the conductive electrode being fixed in the casing insulating body, the casing being grounded.  
     
     
         6 . An apparatus according to  claim 5 , wherein at least part of the casing is covered with an insulating material.  
     
     
         7 . An apparatus according to  claim 6 , wherein the casing has a shelf for mounting an object thereon, the shelf itself being formed as an electrode, a safety being provided to change over impression of a voltage in response to opening and closing of a door on the casing.  
     
     
         8 . An apparatus according to  claim 5 , wherein a shelf made of an insulating material is provided for mounting thereon an object to be treated, a conductive electrode being located on the shelf.  
     
     
         9 . An apparatus according to  claim 4 , wherein the electrode comprises a main body of a conductive electrode, an insulating material which is attached to the main body of the conductive electrode to insulate electrically the main body thereof from a member on which the main body thereof is disposed, and a contact protection member for preventing an operator from touching the main body thereof.  
     
     
         10 . An electrode according to  claim 9 , wherein the insulating material is glass, the main body of the conductive electrode being a fine wire.  
     
     
         11 . An apparatus for treating an object in an electrostatic field, wherein an electrode is inserted into an oil tank of a fryer, a voltage of 100V-1000V being impressed, one pole of the secondary side of a voltage generating device is grounded, a casing of the fryer being set on a floor without earth.