The invention relates to a fluid conveyance system for a fluid, comprising a low-pressure conveyance system having a low-pressure pump (2) and a high-pressure conveyance system having a high-pressure pump (8), which are connected by means of a connecting line, wherein the fluid conveyance system has a pressure damper (19). According to the invention, a fluid conveyance system is provided, by means of which a pulsation of the fluid caused by flow-rate waves or pressure waves in the fluid is damped. This is achieved in that the pressure damper (19) is arranged in the lower-pressure conveyance system and is a hydraulic pressure damper (19). Said hydraulic damper (19) has a piston (21) arranged in a cylinder (20), which piston can be moved against the force of a compression spring (23) and the vapor pressure present in a compression-spring chamber (22) accommodating the compression spring.

A high pressure pump of a common rail pump system includes a pump body having a cylinder with a piston bore and a piston reciprocally driven in the piston bore to pressurize fuel in the cylinder. The piston has an inner end located in the piston bore and an outer end outside the piston bore. A bellow having a first opening and a second opening is arranged between the piston and the pump body, wherein the piston extends through the first and second openings, wherein the bellow is connected to the pump body such that the first opening is sealed on the pump body and wherein the bellow is connected to the outer end of the piston such that the second opening is sealed on the piston. This arrangement prevents mixing of engine oil and fuel. The bellow may be connected to a drainage line via a one-way valve.

An automotive fuel pump having a body with an inlet, an outlet, and an elongated chamber therebetween. A relief valve, relief valve housing, and check valve are respectively disposed in the chamber between the inlet and the outlet. The relief valve housing has a portion which extends across the chamber so that a first axial end of the relief valve housing forms a valve seat for the check valve while the other axial end forms a valve seat for the relief valve. The check valve permits fluid flow from the body chamber to the outlet while the relief valve exhausts excess fluid pressure at the outlet back into the body chamber.

A fuel supply device supplying a fuel stored in a fuel tank to an engine includes a low-pressure pump configured to feed the fuel, a high-pressure pump configured to compress the fuel discharged from the low-pressure pump and to feed to the engine, a first low-pressure passage member configured to define a first fuel passage from the low-pressure pump to the high-pressure pump, and a second low-pressure passage member configured to define a second fuel passage branched from the first fuel passage at a low-pressure junction portion and joining the first fuel passage at a low-pressure confluence portion, wherein the first fuel passage and the second fuel passage are different in at least one of (i) temperatures of the fuels that flow through the fuel passages and (ii) passage lengths of the fuel passages from the low-pressure junction portion to the low-pressure confluence portion.

A partitioning portion partitions a fuel chamber into a first space, which receives a pressurizing chamber forming portion and is communicated with an inflow pipe, and a second space, which is communicated with an outflow pipe. A flow passage forming portion extends from the partitioning portion toward the first space side and forms a communicating flow passage, which communicates between the first space and the second space. Thereby, vapor contained in the fuel, which is returned from a pressurizing chamber to the fuel chamber, is accumulated as bubbles in the first space, which receives the pressurizing chamber forming portion. The first space is communicated with the outside through the communicating flow passage and the second space. Therefore, outputting of air bubbles of the first space to the outside can be effectively limited in comparison to a case where the fuel chamber is directly communicated with the outside.

A pulsation damper is disposed within a fluid volume defined by a fluid volume wall such that the pulsation damper is exposed to pressure pulsations within the fluid volume. The pulsation damper includes a pulsation damper first half having a first damper wall which is flexible in response to the pressure pulsations; a pulsation damper second half having a second damper wall which is flexible in response to the pressure pulsations; and a damping volume defined between the pulsation damper first half and the pulsation damper second half such that the damping volume is fluidly segregated from the fluid volume. One of the pulsation damper first half and the pulsation damper second half defines a spacing member which maintains separation between the fluid volume wall and one of the first damper wall and the second damper wall.

A pulsation damper is disposed within a fluid volume defined by a fluid volume wall such that the pulsation damper is exposed to pressure pulsations within the fluid volume. The pulsation damper includes a pulsation damper first half having a first damper wall which is flexible in response to the pressure pulsations; a pulsation damper second half having a second damper wall which is flexible in response to the pressure pulsations; and a damping volume defined between the pulsation damper first half and the pulsation damper second half such that the damping volume is fluidly segregated from the fluid volume. One of the pulsation damper first half and the pulsation damper second half defines a spacing member which maintains separation between the fluid volume wall and one of the first damper wall and the second damper wall.