A piston assembly is provided for a human-powered vehicle. The piston assembly includes a main body and a primary seal. The main body is configured to be movable from a rest position to an actuated position along an actuation direction in a cylinder bore. The primary seal includes a primary seal body arranged on the main body. The primary seal body is made of a resin material. The main body includes a first part and a second part. The first part is at least partly arranged upstream of the primary seal with respect to the actuation direction. The second part is coupled to the first part to be at least partly arranged downstream of the primary seal with respect to the actuation direction. The at least one of the first part and the second part includes a support portion supporting the primary seal.

A piston for a fluid-actuated working cylinder, with a piston base unit which is coaxial to a piston longitudinal axis, consisting of a rigid core body which has radial outer peripheral surface and of an annular filling body which is seated in an annular receiving groove. The receiving groove is coaxial to the piston longitudinal axis and in the region of the radial outer peripheral surface is designed with a radially outwardly facing groove opening in the core body. The piston further includes a ring element which consists of plastic. The ring element radially outwardly coaxially encompasses the piston base unit at least in the region of the filling body, being radially supported with a radial inner peripheral surface on the piston base unit, projecting radially beyond the radial outer peripheral surface of the core body and comprising an axially orientated axial support surface radially outside the piston base unit on its two axial face sides. The piston further includes an annular enveloping body which has rubber elastic characteristics.

A piston for a compressor is disclosed. The piston for the compressor compressing and discharging a refrigerant sucked into a cylinder includes a sliding portion disposed in the cylinder and having a suction space to receive the sucked refrigerant, a head portion coupled to the sliding portion, a compression space being formed at a front of the head portion and the suction space being formed at a rear of the head portion, the head portion comprising a suction port communicating the suction space with the compression space, a press-fit cap coupled to the front of the head portion, the press-fit cap comprising a suction hole connected to the suction port, and a first elastic member disposed between the press-fit cap and the head portion. A gas layer is formed between the head portion, the press-fit cap, and the first elastic member.

A piston assembly is provided for a human-powered vehicle. The piston assembly includes a main body and a primary seal. The main body is configured to be movable from a rest position to an actuated position along an actuation direction in a cylinder bore. The primary seal includes a primary seal body arranged on the main body. The primary seal body is made of a resin material. The main body includes a first part and a second part. The first part is at least partly arranged upstream of the primary seal with respect to the actuation direction. The second part is coupled to the first part to be at least partly arranged downstream of the primary seal with respect to the actuation direction. The at least one of the first part and the second part includes a support portion supporting the primary seal.

A piston (1) comprising a first portion (10) suitable for coupling with an actuator member (53) and a second portion (20) made of ceramic material suitable for sliding in a cylinder (51). The first portion (10) and the second portion (20) are axially connected along a longitudinal axis (L) of the piston (1). The second portion (20) has an elongated shape along the longitudinal axis (L) of the piston (1), with an interface base (21) proximal to the first portion (10) and a free base (23) distal from the first portion (10). Moreover, the free base (23) is closed and entirely defines a piston crown.

A multilayer piston insulator may comprise a plurality of axially aligned disks of a disk stack comprising, a first disk, a second disk, and a third disk, wherein the second disk is coupled axially between the first disk and the third disk and comprises a different material than the third disk, and wherein the disk stack is configured to couple to a hydraulic piston.

A piston for a compressor is disclosed. The piston for the compressor compressing and discharging a refrigerant sucked into a cylinder includes a sliding portion disposed in the cylinder and having a suction space to receive the sucked refrigerant, a head portion coupled to the sliding portion, a compression space being formed at a front of the head portion and the suction space being formed at a rear of the head portion, the head portion comprising a suction port communicating the suction space with the compression space, a press-fit cap coupled to the front of the head portion, the press-fit cap comprising a suction hole connected to the suction port, and a first elastic member disposed between the press-fit cap and the head portion. A gas layer is formed between the head portion, the press-fit cap, and the first elastic member.

A piston (1) comprising a first portion (10) suitable for coupling with an actuator member (53) and a second portion (20) made of ceramic material suitable for sliding in a cylinder (51). The first portion (10) and the second portion (20) are axially connected along a longitudinal axis (L) of the piston (1). The second portion (20) has an elongated shape along the longitudinal axis (L) of the piston (1), with an interface base (21) proximal to the first portion (10) and a free base (23) distal from the first portion (10). Moreover, the free base (23) is closed and entirely defines a piston crown.

There is provided an engine piston including a piston main body and a piston pin. The piston main body includes a piston head that has a crown surface forming a part of a wall of a combustion chamber and a pair of pin bosses that are connected to a side of the piston head opposite to the crown surface, arranged with a distance between the pin bosses in a first direction included in a radial direction of the piston head, and respectively have pin holes for the piston pin, the pin holes penetrating in the first direction. The piston head includes a pair of hollow parts extending in a second direction orthogonal to both the axial direction and the first direction at a position between the crown surface and each of the pin holes in the axial direction and a particulate filler filled in the pair of hollow parts.

A high pressure fuel pump includes a pumping head and a plunger slidably adjusted in a bore. The plunger is provided with a blind bore defining a chamber open in the head end of the plunger and in fluid communication with the compression chamber, the end face of the plunger being limited to a peripheral annular face surrounding the opening, the bore further defining a peripheral cylindrical wall and a bottom face. A filler member is arranged inside the chamber.