Abstract: A diaphragm having an outer surface of a bottom wall that closes a cylindrical circumferential wall constituting a main valve disc part forms a contact surface to be in contact with a valve seat. An annular groove is formed in an inner circumferential portion of a membrane part protruding from the circumferential wall. The groove is concaved to the other axial side from the one axial side, and a sectional shape of the groove is arcuate. A surface of the inner circumferential portion and a surface of the outer circumferential portion in the membrane part are coplanar, the surfaces facing the other axial side. An axial thickness of the outer circumferential portion is ?-? an axial thickness of the main valve disc part, and a minimum axial thickness of the inner circumferential portion is ¼-? the axial thickness of the outer circumferential portion.

Abstract: The main component of a valve body is a ternary fluororubber of a vinylidene fluoride/tetrafluoroethylene/hexafluoropropylene copolymer, the JIS K 6253 hardness of the valve body is 50-90, the tensile strength of the valve body is 10-35 MPa, and the elongation at break of the valve body is 100-500%. Relative to the inside diameter of a gas discharge channel provided to an inner-side area of the valve seat, the distance by which a movable core is moved by an electromagnetic coil is within a range of 0.1 times to 0.3 times, the diameter of the valve body is within a range of 1.5 times to 3.0 times, the thickness of the valve body is 0.3 times or greater, the protruding height of the valve seat is 0.3 times or greater, and the inside diameter of an annular gas accumulating space is 2.0 times to 5.0 times.

Abstract: A diaphragm having an outer surface of a bottom wall that closes a cylindrical circumferential wall constituting a main valve disc part forms a contact surface to be in contact with a valve seat. An annular groove is formed in an inner circumferential portion of a membrane part protruding from the circumferential wall. The groove is concaved to the other axial side from the one axial side, and a sectional shape of the groove is arcuate. A surface of the inner circumferential portion and a surface of the outer circumferential portion in the membrane part are coplanar, the surfaces facing the other axial side. An axial thickness of the outer circumferential portion is ?-? an axial thickness of the main valve disc part, and a minimum axial thickness of the inner circumferential portion is ¼-? the axial thickness of the outer circumferential portion.

Abstract: A heat exchanger provided with: a plate member having a flat bottom part and a refrigerant flow path formed therein; and a plate cover for covering the plate member. The plate cover has a refrigerant inlet communicating with an area on one side of the refrigerant flow path, and a refrigerant outlet communicating with an area on the other side of the refrigerant flow path. The refrigerant flow path is more densely arranged in an area far from a straight line connecting the area that is on the one side and communicates with the refrigerant inlet to the area that is on the other side and communicates with the refrigerant outlet, than in an area close to the straight line connecting the area that is on the one side and communicates with the refrigerant inlet to the area that is on the other side and communicates with the refrigerant outlet.

Abstract: The main component of a valve body is a ternary fluororubber of a vinylidene fluoride/tetrafluoroethylene/hexafluoropropylene copolymer, the JIS K 6253 hardness of the valve body is 50-90, the tensile strength of the valve body is 10-35 MPa, and the elongation at break of the valve body is 100-500%. Relative to the inside diameter of a gas discharge channel provided to an inner-side area of the valve seat, the distance by which a movable core is moved by an electromagnetic coil is within a range of 0.1 times to 0.3 times, the diameter of the valve body is within a range of 1.5 times to 3.0 times, the thickness of the valve body is 0.3 times or greater, the protruding height of the valve seat is 0.3 times or greater, and the inside diameter of an annular gas accumulating space is 2.0 times to 5.0 times.

Abstract: A heat exchanger provided with: a plate member having a flat bottom part and a refrigerant flow path formed therein; and a plate cover for covering the plate member. The plate cover has a refrigerant inlet communicating with an area on one side of the refrigerant flow path, and a refrigerant outlet communicating with an area on the other side of the refrigerant flow path. The refrigerant flow path is more densely arranged in an area far from a straight line connecting the area that is on the one side and communicates with the refrigerant inlet to the area that is on the other side and communicates with the refrigerant outlet, than in an area close to the straight line connecting the area that is on the one side and communicates with the refrigerant inlet to the area that is on the other side and communicates with the refrigerant outlet.