Abstract: Provided is a zinc base alloy having high strength, and being excellent in toughness and abrasion resistance. The zinc base alloy contains 3.5% by weight or more and 4.5% by weight or less of Al, 3.0% by weight or more and 4.0% by weight or less of Cu, 0.01% by weight or more and 0.08% by weight or less of Mg, 0.005% by weight or more and 0.1% by weight or less of Ca, and, as necessary, 0.005% by weight or more and 0.1% by weight or less of Sr, and balance of Zn and inevitable impurities. Also provided is a die-cast product made from the zinc base alloy.

Abstract: Provided is a zinc base alloy having high strength, and being excellent in toughness and abrasion resistance. The zinc base alloy comprises 3.5% by weight or more and 4.5% by weight or less of Al, 3.0% by weight or more and 4.0% by weight or less of Cu, 0.01% by weight or more and 0.08% by weight or less of Mg, 0.005% by weight or more and 0.1% by weight or less of Ca, and, as necessary, 0.005% by weight or more and 0.1% by weight or less of Sr, and balance of Zn and inevitable impurities. Also provided is a die-cast product made from the zinc base alloy.

Abstract: A hydraulic shock absorber is provided with a cylinder formed of a straight pipe, and inside the cylinder, opposite end portions of a base piston are fixed to the inner face by a pair of retainer member C-rings so that a free piston can be received in a lower portion of the cylinder.

Abstract: A main piston which divides the inside of a cylinder into chambers A and B has oil passages on the expanding side formed therethrough, and is mounted with a damping valve on the expanding side capable of closing the oil passages. The damping valve on the expanding side deforms in a deflecting manner to produce a damping force. A disc spring is disposed behind the damping valve on the expanding side to exert a biasing force on the rear face thereof. The disc spring is linked in an actuating manner to an operating rod mounted through a piston rod, thereby allowing a change of the biasing force exerted on the damping valve on the expanding side.