Ink jet apparatus with a flexible piezoelectric member and method of operating same

An ink jet apparatus comprising:

• an elastic tubular member forming, at least in part, a chamber for receiving ink, said tubular member comprising rubber and piezoelectric crystals substantially uniformly dispersed through said member and having electromechanical transducer properties;
• an orifice in said chamber adapted to pass droplets of ink;
• means for supplying ink to said chamber;
• and
• means for relatively energizing said tubular member so as to contract and expand said chamber, said orifice projecting droplets outwardly therefrom when said chamber contracts.

An ink jet apparatus comprising:

• an elastic tubular member forming, at least in part, a chamber for receiving ink, said tubular member having electromechanical transducer properties;
• a plurality of conductive coatings electrically isolated on the surface of said member;
• an orifice in said chamber adapted to pass droplets of ink;
• means for supplying ink to said chamber;
• and
• means for relatively energizing said tubular member so as to contract and expand said chamber, said means for relatively energizing including means for sequentially energizing said flexible member at said plurality of coatings for creating a pressure wave through said chamber to project droplets outwardly from said orifice.

An ink jet comprising:

• a member comprising a substantially homogeneous mixture of piezoelectric material and an elastic binder, said member forming at least in part a chamber adapted to receive ink,
• an orifice in said chamber having a maximum dimension not more than 4 mils nor less than 1 mil so as to permit the projection of ink droplets therethrough;
• and
• means for relatively energizing said tubular member so as to contract and expand said chamber, said means further comprising a plurality of conductive coatings on the exterior of said member outside said chamber, said coatings being mutually electrically separated on said exterior.

The method of operating an ink jet including an elastic member comprising a substantially homogeneous mixture of piezoelectric material and elastic binder, said member forming at least in part an ink receiving chamber having an orifice therein, said method comprising the following steps:

• supplying ink to said chamber;
• electrically energizing said member so as to alter the volume of said chamber;
• and
• projecting a droplet of ink in response to a change in the volume of said member.