Abstract: In a fuel supply apparatus disclosed, a variable displacement mechanism is driven once every two or more reciprocating motions of the plunger of a high-pressure fuel pump to control the delivery flow rate, so that the delivery flow rate control can be performed without having to raise the responsiveness of the variable displacement mechanism even when the reciprocating cycle of the plunger is short.

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 gear pump has a pair of gears a seal member for sealing up teeth of the gross engaging with each other in a sealed-up gear case, which seal member is provided at a place occupied by plurality of teeth in the vicinity of a working area of the teeth in a low pressure side of the gear case and is not connected to the gear case, the seal member having a low pressure fuel the flow of hole for flowing a low pressure fuel, wherein a tooth sealing angle for the plurality of teeth is set substantially to a value within a range of 35.degree..+-.5.degree. for gears having of 14 to 18 teeth, and a high pressure fuel flowing passage for the flow of a high pressure fuel, formed in a space other than the working area of the teeth and the area of and the sealing member, in the gear case.

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.

Abstract: A widthwise-compressing machine for applying a compression force through press tools to a material to reduce a width of the material while applying vibrations to said material to forcibly vibrate said material has a compression unit for producing a compression force forming a working force, and a vibration-applying unit for applying the vibration to said material. The vibration-applying unit is provided independently of the compression unit. In the widthwise-compressing machine, when the material is plastically worked, the material can be vibrated at an extremely high frequency to make it possible to resonate the material, thereby allowing the plastic-deformation thereof to be promoted.