Pneumatic cylinder device with holding valve

1. A pneumatic cylinder device comprising:

an output member ( 7 ) inserted in a housing ( 5 ) so as to be movable in its axial direction;

a first actuation chamber ( 20 ) provided in a base end side of the housing in the axial direction of the output member ( 7 );

a second actuation chamber ( 21 ) provided in a leading end side of the housing in the axial direction of the output member ( 7 );

a first supply and discharge passage ( 24 ) which is provided in the housing ( 5 ) and through which compressed air is supplied to and discharged from the first actuation chamber ( 20 );

a second supply and discharge passage ( 26 ) which is provided in the housing ( 5 ) and through which compressed air is supplied to and discharged from the second actuation chamber ( 21 ); and

a first holding valve ( 30 ) provided to an intermediate portion of the first supply and discharge passage ( 24 ), the first holding valve ( 30 ) being configured to close and open the first supply and discharge passage ( 24 ), wherein

the first holding valve ( 30 ) includes:

a first casing ( 32 ) of the first holding valve ( 30 ), the first casing ( 32 ) being attached in a first attachment hole ( 31 ) provided in the housing ( 5 );

a first valve hole ( 33 ) provided in the first casing ( 32 );

a first valve seat ( 34 ) provided on an inner peripheral wall of the first valve hole ( 33 );

a first valve member ( 35 ) inserted in the first valve hole ( 33 ) so as to be movable, the first valve member ( 35 ) being biased by a first valve-closing spring ( 38 ) toward the first valve seat ( 34 );

a first operation member ( 39 ) hermetically inserted in a portion of the first valve hole ( 33 ) so as to be movable, the portion being opposite to the first valve member ( 35 ) across the first valve seat ( 34 ), the first operation member ( 39 ) being opposed to the first valve member ( 35 ) with a predetermined gap therebetween so as to be contactable with the first valve member ( 35 );

a first pressure-receiving chamber ( 41 ) provided close to a first end surface of the first operation member ( 39 ), the first end surface being opposite from a second end surface thereof facing the first valve member ( 35 ); and

a first communication passage ( 44 ) which communicatively connects the second actuation chamber ( 21 ) to the first pressure-receiving chamber ( 41 );

wherein a holding spring ( 22 ) is attached in the first actuation chamber ( 20 ) and between the output member ( 7 ) and a base end wall ( 5 a ) of the housing ( 5 ).

2. The pneumatic cylinder device according to claim 1 , further comprising

a second holding valve ( 50 ) provided to an intermediate portion of the second supply and discharge passage ( 26 ), the second holding valve ( 50 ) being configured to close and open the second supply and discharge passage ( 26 ), wherein

the second holding valve ( 50 ) includes:

a second casing ( 52 ) of the second holding valve ( 50 ), the second casing ( 52 ) being attached in a second attachment hole ( 51 ) provided in the housing ( 5 );

a second valve hole ( 53 ) provided in the second casing ( 52 );

a second valve seat ( 54 ) provided on an inner peripheral wall of the second valve hole ( 53 );

a second valve member ( 55 ) inserted in the second valve hole ( 53 ) so as to be movable, the second valve member ( 55 ) being biased by a second valve-closing spring ( 58 ) toward the second valve seat ( 54 );

a second operation member ( 59 ) hermetically inserted in a portion of the second valve hole ( 53 ) so as to be movable, the portion being opposite to the second valve member ( 55 ) across the second valve seat ( 54 ), the second operation member ( 59 ) being opposed to the second valve member ( 55 ) with a predetermined gap therebetween so as to be contactable with the second valve member ( 55 );

a second pressure-receiving chamber ( 61 ) provided close to a first end surface of the second operation member ( 59 ), the first end surface being opposite from a second end surface thereof facing the second valve member ( 55 ); and

a second communication passage ( 64 ) which communicatively connects the first actuation chamber ( 20 ) to the second pressure-receiving chamber ( 61 ).

3. A pneumatic cylinder device comprising:

an output member ( 7 ) inserted in a housing ( 5 ) so as to be movable in its axial direction;

a first actuation chamber ( 20 ) provided on in a base end side of the housing in the axial direction of the output member ( 7 );

a second actuation chamber ( 21 ) provided in a leading end side of the housing in the axial direction of the output member ( 7 );

a first supply and discharge passage ( 24 ) which is provided in the housing ( 5 ) and through which compressed air is supplied to and discharged from the first actuation chamber ( 20 );

a second supply and discharge passage ( 26 ) which is provided in the housing ( 5 ) and through which compressed air is supplied to and discharged from the second actuation chamber ( 21 ); and

a second holding valve ( 50 ) provided to an intermediate portion of the second supply and discharge passage ( 26 ), the second holding valve ( 50 ) being configured to close and open the second supply and discharge passage ( 26 ), wherein

the second holding valve ( 50 ) includes:

a second casing ( 52 ) of the second holding valve ( 50 ), the second casing ( 52 ) being attached in a second attachment hole ( 51 ) provided in the housing ( 5 );

a first valve hole ( 53 ) provided in the second casing ( 52 );

a second valve seat ( 54 ) provided on an inner peripheral wall of the second valve hole ( 53 );

a second valve member ( 55 ) inserted in the second valve hole ( 53 ) so as to be movable, the second valve member ( 55 ) being biased by a second valve-closing spring ( 58 ) toward the second valve seat ( 54 );

a second operation member ( 59 ) hermetically inserted in a portion of the second valve hole ( 53 ) so as to be movable, the portion being opposite to the second valve member ( 55 ) across the second valve seat ( 54 ), the second operation member ( 59 ) being opposed to the second valve member ( 55 ) with a predetermined gap therebetween so as to be contactable with the second valve member ( 55 );

a second pressure-receiving chamber ( 61 ) provided close to a first end surface of the second operation member ( 59 ), the first end surface being opposite from a second end surface thereof facing the second valve member ( 55 ); and

a second communication passage ( 64 ) which communicatively connects the first actuation chamber ( 20 ) to the second pressure-receiving chamber ( 61 ).