Abstract: An intake valve automatically opened and closed by pressure of a pressuring chamber is provided in a fuel intake passage, the intake valve is pushed to open by a plunger of an electromagnetic plunger mechanism, pulling-in operating timing of the plunger is controlled according to the operating condition of an internal combustion engine, and opening time of the intake valve during compression stroke of a pump is controlled to make discharge flow-rate of high pressure fuel variable.

Abstract: A fuel feed system capable of feeding a fuel to fuel injection valves at a fuel pressure with improved stability is provided. A fuel feed system for an internal combustion engine including a fuel tank and a low-pressure pump for feeding the fuel in the fuel tank to fuel injection valves, is provided with a diaphragm type damper having a wave-shape cross section at a position in contact with the fuel.

Abstract: A fuel feed system capable of feeding a fuel to fuel injection valves at a fuel pressure with improved stability is provided. A fuel feed system for an internal combustion engine including a fuel tank and a low-pressure pump for feeding the fuel in the fuel tank to fuel injection valves, is provided with a diaphragm type damper having a wave-shape cross section at a position in contact with the fuel.

Abstract: A fuel feed system capable of feeding a fuel to fuel injection valves at a fuel pressure with improved stability is provided. A fuel feed system for an internal combustion engine including a fuel tank and a low-pressure pump for feeding the fuel in the fuel tank to fuel injection valves, is provided with a diaphragm type damper having a wave-shape cross section at a position in contact with the fuel.

Abstract: A simple structured high-pressure fuel pump. A fuel pump comprises a reciprocably-supported cylinder, a pressurizing chamber using part of the outer surface of the cylinder as the wall surface which move to change the internal volume, a fuel intake passage forming a fuel passage which introduces fuel to the pressurizing chamber, a fuel discharge passage for the compressed fuel coming out from the pressurizing chamber. A fuel intake valve is provided in fuel intake passage. A fuel discharge valve is provided in said fuel discharge passage. A connecting passage connects upstream side of the intake valve in the fuel intake passage and the downstream side of it. A check valve which flows fuel from the fuel discharge flow passage to the fuel intake passage is provided in the connecting passage.

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: An intake valve automatically opened and closed by pressure of a pressuring chamber is provided in a fuel intake passage, the intake valve is pushed to open by a plunger of an electromagnetic plunger mechanism, pulling-in operating timing of the plunger is controlled according to the operating condition of an internal combustion engine, and opening time of the intake valve during compression stroke of a pump is controlled to make discharge flow-rate of high pressure fuel variable.

Abstract: A high-pressure fuel feed pump, wherein a pump housing is formed of an aluminum alloy, a cylinder is formed of iron base metal, the flange part of a flanged tube member is held in a contact part between the pump housing and the cylinder, the tube member is installed in the pump housing along the inner wall surface thereof. As a result, a seal surface is not corroded directly since cavitation occurs between the tip of the tube member and the pump housing.

Abstract: A fluid pump, wherein a cylinder supporting a plunger and a pump housing are formed with dissimilar metals and a pressing mechanism to press the cylinder and the pump housing relatively to each other is provided so that a pressurizing chamber is sealed through a pressing surface between the pump housing and the cylinder, whereby the number of seal points can be reduced and a reduction in reliability can be eliminated while realizing a reduction in weight of the pump housing and a reduction in cost due to increase in cutting capability using a soft member such as aluminum alloy for the pump housing.

Abstract: A simple structured high-pressure fuel pump.

Abstract: An intake valve automatically opened and closed by pressure of a pressuring chamber is provided in a fuel intake passage, the intake valve is pushed to open by a plunger of an electromagnetic plunger mechanism, pulling-in operating timing of the plunger is controlled according to the operating condition of an internal combustion engine, and opening time of the intake valve during compression stroke of a pump is controlled to make discharge flow-rate of high pressure fuel variable.

Abstract: A fuel feed system capable of feeding a fuel to fuel injection valves at a fuel pressure with improved stability is provided. A fuel feed system for an internal combustion engine including a fuel tank and a low-pressure pump for feeding the fuel in the fuel tank to fuel injection valves, is provided with a diaphragm type damper having a wave-shape cross section at a position in contact with the fuel.

Abstract: In a fuel pump pressurizing fuel and supplying the fuel to a fuel injection valve of a vehicle engine, a hardened layer of at least one selected from a nitride layer, a carburated and quenched layer and a carbonitrided layer, and a metal compound layer, on a surface of the hardened layer, higher in corrosion resistance than the hardened layer are formed on one of slide surfaces contacting each other and sliding in fuel.

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: A fuel supply system for a direct injection engine which has a variable capacity single cylinder plunger pump and two fuel rails. Offices are disposed at the upstream side inlets of both fuel rails, respectively. At the opposite sides to the inlet sides, the fuel rails are interconnected with each other by a connecting pipe. Using this fuel supply system, it is possible to increase a characterisitic frquency of the fuel columns, and to stabilize, suppress, and smooth out pressure pulsation in the fuel rails, thereby reducing uneven fuel injections into the cylinders. The system may have a cam which drives a plunger of a high pressure fuel pump to reciprocate once for every two combustions in two engine cylinders.

Abstract: A fuel supply system for a direct injection engine which has a variable capacity single cylinder plunger pump and two fuel rails. There are disposed orifices at the upstream side inlets of the both fuel rails, respectively. At the opposite sides to the inlet sides, the fuel rails are interconnected with each other by a connecting pipe. By the fuel supply system, it is capable of increasing a characteristic frequency of the fuel columns, and of stabilizing, suppressing, and smoothing out pressure pulsation in the fuel rails, thereby reducing uneven fuel injections into the cylinders. The system may have a cam which drives a plunger of a high pressure fuel pump to reciprocate once for every two combustion in two engine cylinders.

Abstract: A fuel feeding apparatus includes a pressure increasing piston system, in addition to a high pressure fuel pump, for further increasing the fuel pressure at the outlet of the high pressure fuel pump. For this purpose, a first piston provided in a first cylinder is moved in response to the pressure of fuel drawn up from a fuel tank and fed to the high pressure pump by a low pressure fuel feed pump, and a second piston provided in a second cylinder and having a diameter smaller than the diameter of the first piston is connected to the first piston and is moved together with the first piston for pressurizing fuel in the second cylinder communicating with the outlet of the high pressure fuel pump at the time of engine starting, and before the high pressure fuel pump is started.