Abstract: This invention relates to a vane pump having a cover of simple construction and which permits reduction of production costs. A groove-shaped low pressure port 6A and a branch groove 6 split into two are formed in the cover joined to a body. A pin extending by a predetermined amount from an end face of the body is implanted in a side plate. A throughhole through which the pin passes is formed in a cam ring, and a concave part 25 of predetermined depth for engaging with the end of the pin is formed in the cover. An escape hole 24 is also formed in the cover for housing the tip end of the drive shaft extending from the end face of the body. A shoulder part is formed on the inner circumference of a shaft hole in the body which engages or disengages with a step between the large diameter part and the small diameter part of the drive shaft.

Abstract: A vane pump is provided which does not require a core and wherein a cover is formed by diecasting. A body 1 supports a drive shaft 50 and houses a cam ring 30. A side plate 8 is interposed between the body 1 and cam ring 30. Low pressure ports 82 connected to intake areas of the cam ring 30, and high pressure ports 81 connected to discharge areas of the cam ring 30 and a high pressure port 12 inside the body 1, are respectively arranged symmetrically in the side plate 8. Branch passages 13 connected to a low pressure passage 9 are formed from an intake chamber 10 along the outer circumference of the cam ring 30 between the inner circumference of the body 1 and upper semicircular part of the cam ring 30. A cover 2 joined to the open end of the body 1 comprises an end face 2A which comes in contact with one face of the cam ring 30. Branch grooves 6 are formed in the end face 2A at positions corresponding to the intake areas of the cam ring 30.

Abstract: An easily assembled, low cost pressure switch for a hydraulic pump is proposed. An oil pressure introducing hole is provided for leading a discharge pressure to a depression formed in a body which is earthed. A plug supporting an electrically conducting terminal in an insulated state so as to block the depression, comprises a cylindrical part opening into the depression of the body. An electrically conducting sleeve which is pierced by a damping orifice connected to the oil pressure introducing hole, engages with an opening of the cylindrical part. An electrically conducting plunger which comes in contact with and separates from the terminal in response to an oil pressure from the damping orifice, is housed in the sleeve. A spring pushing the plunger against the oil pressure is housed in the cylindrical part of the plug, and the lower end of the sleeve engages with the opening of the oil pressure introducing hole.

Abstract: A pallet for carrying a driver's seat and an assistant driver's seat, or a seat for several passengers, comprising a substantially rectangle-shaped base plate, a frame-like rising section of a substantially rectangle-shape rising from a surface of the base plate, on which the driver's seat and assistant driver's seat or the seat for several passengers are to be carried, and surrounding said base plate, the base plate and frame-like rising section formed as one piece, by reaction injection molding, of resinous material containing as the main component thereof dicyclopentadiene which is C.sub.