Abstract: Two oil chambers 28. 29 are formed in a cylinder 21. The piston rod oil chamber 28 is connected with a reservoir 50 formed on an outer section of the cylinder. Two parallel passages 33, 34 are formed in a sealing case 23 provided on an upper section of the cylinder. The sealing case 23 is provided with a needle valve 35 regulating the area of the opening of the passage 33, a poppet valve 37 closing the oil chamber 34 with the biasing force of the spring 40 and an adjuster 39 regulating the biasing force of the spring 40. A part of the oil flowing out of the oil chamber 28 in an expansion stroke is discharged through the needle valve 35 and the puppet valve 37 in order to allow respective regulation of the damping force at that time.

Abstract: A hydraulic shock absorber comprises a cylinder (11) with an expandable and contractible piston rod (12), an outer casing (13) disposed on the outside of the cylinder (11), and a reservoir (16) defined between the outer casing and the cylinder. Due to an elastically deformable bladder (14) disposed inside the reservoir, a gas chamber (17) in which gas is sealed is formed between the bladder and the outer casing, and a reservoir chamber (18) communicated with the inside of the cylinder and designed for guiding hydraulic fluid is formed between the bladder and the cylinder. Furthermore, a gas sealing valve (23) for opening and closing a flow conduit (24) communicated with the gas chamber provided to part of the outer casing is provided to a bottom portion (19) of the outer casing, and allowing gas to enter and exit the gas chamber via the gas sealing valve makes it possible to freely adjust the gas pressure in the hydraulic shock absorber from the outside.

Abstract: Two oil chambers 28. 29 are formed in a cylinder 21. The piston rod oil chamber 28 is connected with a reservoir 50 formed on an outer section of the cylinder. Two parallel passages 33, 34 are formed in a sealing case 23 provided on an upper section of the cylinder. The sealing case 23 is provided with a needle valve 35 regulating the area of the opening of the passage 33, a poppet valve 37 closing the oil chamber 34 with the biasing force of the spring 40 and an adjuster 39 regulating the biasing force of the spring 40. A part of the oil flowing out of the oil chamber 28 in an expansion stroke is discharged through the needle valve 35 and the puppet valve 37 in order to allow respective regulation of the damping force at that time.

Abstract: A hydraulic shock absorber comprises a cylinder (11) with an expandable and contractible piston rod (12), an outer casing (13) disposed on the outside of the cylinder (11), and a reservoir (16) defined between the outer casing and the cylinder. Due to an elastically deformable bladder (14) disposed inside the reservoir, a gas chamber (17) in which gas is sealed is formed between the bladder and the outer casing, and a reservoir chamber (18) communicated with the inside of the cylinder and designed for guiding hydraulic fluid is formed between the bladder and the cylinder. Furthermore, a gas sealing valve (23) for opening and closing a flow conduit (24) communicated with the gas chamber provided to part of the outer casing is provided to a bottom portion (19) of the outer casing, and allowing gas to enter and exit the gas chamber via the gas sealing valve makes it possible to freely adjust the gas pressure in the hydraulic shock absorber from the outside.

Abstract: A damper assembly, for supporting a seat of a vehicle such as a small-sized motor boat, comprises a lower bracket adapted to be attached to a floor of the vehicle, an upper bracket adapted to be attached to the seat, and a damper mounted between the upper and lower brackets. The damper includes an outer tube extending upwardly from the lower bracket, an inner tube extending downwardly from the upper bracket and telescopically inserted in the outer tube, and a guide tube secured to the lower bracket and telescopically inserted in the inner tube. The inner and guide tubes are connected together so as to allow the inner tube to slide longitudinally on the guide tube but so as to prevent the inner tube from rotation or turning about the guide tube.