Provided is a check valve including: a duckbill valve; and a support member which is inserted into an inside portion of the duckbill valve, in which the duckbill valve includes a slit which is provided on a side where fluid is discharged, an inflow port which is provided on a side where the fluid flows in, and a flow path which connects the inflow port to the slit, and in which the support member is inserted into the flow path from the inflow port, a hole for sending the fluid to the slit when flowing in from the inflow port is provided, and the hole is provided so as to be hermetically sealed by the duckbill valve when a negative pressure is applied from the inflow port side.

A compressor includes a discharge valve with a first valve head and a second valve head. The first valve head defines a passage that extends through the first valve head along an axial direction. A first spring is coupled to the first valve head. A second valve head is positioned at the passage of the first valve head. A second spring urges the second valve head towards the first valve head.

The modification of the suction holes of the valve plate would increase the refrigerant flow rate of the compressor. The modified suction holes (11 and 12) are specially designed to have tapering form with the larger diameter at the top and smaller at the bottom (20). The valve plate partition (16) has the same height as the valve plate. These will reduce the friction loss of the refrigerant in the cylinder, which will result in an improvement of the refrigerant flow rate, more suction pressure, and the higher coefficient discharge.

Provided is a valve module that includes a movable member and a support member. The movable member is constituted by a film elastically deformable by a fluid and having a first surface positioned on a side of a member having an opening through which the fluid passes and a second surface on a side opposite to the first surface. The support member has higher rigidity than rigidity of the movable member, covers a part of a region of the second surface, in which the opening is not located as viewed in a direction perpendicular to the second surface, and is fixed to the member.

An air stop sheet of a piston of a cylinder, the piston is accommodated in an air compressor, and an air stop sheet is accommodated on a head of the piston. The air stop sheet includes a bending section having a positioning zone and an acting zone and configured to be a boundary line of the acting zone and the positioning zone. The acting zone backing the cylinder turns on relative to the plane of the head at an open angle , thus producing an air flowing space. A piston rod extends downward from the head and includes a cavity, an air conduit, a column, and a spring configured to abut against the acting zone of the air stop sheet. The air stop sheet is pushed by the spring to turn on at an open angle , and the air conduit and the air channel communicate with atmosphere.

An improved air compressor generally includes a cylinder fitted with a piston body, a main frame for mounting a motor, and an air storage container. The cylinder, which defines a plurality of exit holes, is formed integrally with the main frame. The compressed air produced in the cylinder can quickly enter the air storage container via the exit holes, so that the piston body can conduct reciprocating motion more smoothly and thus the performance of the air compressor can be increased.

An improved air compressor includes a cylinder fitted with a piston body, a main frame for mounting a motor, and an air storage container. The cylinder defines a plurality of exit holes regulated by a control mechanism including a resilient sheet having a root and a plurality branches corresponding to the exit holes. The root and branches of the resilient sheet are individually attached to a top wall of the cylinder at separate points, so that each of the branches can be individually moved by the compressed air produced in the cylinder to open or close the corresponding exit hole without affecting movements of the other branches, so that the piston body can conduct reciprocating motion more smoothly, and thus the performance of the air compressor can be increased.

A reciprocating compressor includes: a cylinder forming a cylinder chamber; an intake valve disposed around the cylinder chamber; a movable part including either an intake valve seat configured to seat the intake valve or a back member located on an opposite side of the intake valve from the intake valve seat, and configured to move in an axial direction of the cylinder; and an actuator for moving the movable part in the axial direction to change a movable range of the intake valve between the intake valve seat and the back member.

Constructive disposition introduced in reciprocating compressor suction valve, whose moving parameters of elastic flexion area and, therefore, sealing end are mainly defined by specific geometries and dimensions of the own flexible segment of suction valve. Furthermore, the stiffness coefficient and natural frequency of flexible segment of suction valve are also defined from specific geometries and dimensions of the own flexible segment of suction valve, without being necessary to alter the material or thickness of metallic blade where the suction valve is defined.

A compressor includes a member with a recess in which a reed discharge valve is disposed. The recess has a discharge hole, a fixation hole, and an annular projection formed around the discharge hole. The discharge valve includes a fixed portion, a flexible portion, and a head portion to open/close the annular projection. A protruding portion is formed at a rear end portion of the fixed portion. A first side surface of the protruding portion is designed to be substantially flush with a side surface of the fixed portion, which surface is closer to a center of the member. When the discharge valve rotates in a predetermined direction about the fixation hole after the discharge valve is disposed in the recess but before being fixed to the member, the first side surface of the protruding portion comes into contact with a side wall of the recess.