Abstract: A check seal (53) for discharging working oil scraped off a piston rod (3) by an oil lip (52b) into an oil pool (A) of a hydraulic shock absorber to an oil reservoir (R) is disposed on the outside of the oil pool (A). The check seal (53) comprises an annular seat surface (4d) and an annular lip (53a) seated resiliently on the seat surface (4d). The annular seat surface (4d) comprises an annular main rib (11) and an annular inner rib (12), both of which project toward the annular lip (53a), such that an annular groove (21) is formed between the main rib (11) and the inner rib (12). By providing a pressure introducing passage (12a) to introduce a pressure inside the inner rib (12) to the annular groove (21), the check seal (53) exhibits a high working oil discharging performance and a high working oil sealing performance.

Abstract: There is provided a hydraulic damper including a receiving space formed between a rod guide of a cylinder and an insert metal, for temporarily retaining a working fluid leaked out from an oil chamber through a sliding gap of a rod. The hydraulic damper further includes a communicating path for communicating between a reservoir and the receiving space, and a check valve for allowing a flow of the working fluid only from the receiving space to the reservoir. Either one of a lip part of the check valve or a seat surface provided on the rod guide is formed with a sealing projected part protruding from a mutual contact surface.

Abstract: A check seal (53) for discharging working oil scraped off a piston rod (3) by an oil lip (52b) into an oil pool (A) of a hydraulic shock absorber to an oil reservoir (R) is disposed on the outside of the oil pool (A). The check seal (53) comprises an annular seat surface (4d) and an annular lip (53a) seated resiliently on the seat surface (4d). The annular seat surface (4d) comprises an annular main rib (11) and an annular inner rib (12), both of which project toward the annular lip (53a), such that an annular groove (21) is formed between the main rib (11) and the inner rib (12). By providing a pressure introducing passage (12a) to introduce a pressure inside the inner rib (12) to the annular groove (21), the check seal (53) exhibits a high working oil discharging performance and a high working oil sealing performance.

Abstract: In a shock absorber (D), a rod (3) projects axially from a cylinder (1) housed in an outer tube (2) to the exterior of the outer tube (2). A rod guide (4, 11) supports the outer circumference of the rod (3) so as to be free to slide. The rod guide (4, 11) also closes openings of the cylinder (1) and the outer tube (2). The rod guide (4, 11) comprises a cylindrical part (4a, 11a) which is inserted into the cylinder (1). By inserting a cylindrical spacer (5, 12) between the cylindrical part (4a, 11a) of the rod guide (4) and the inner circumference of the cylinder (1) so as to compensate for a gap therebetween, plural shock absorbers (D) comprising cylinders (1) of different inner diameters can be manufactured using rod guides (4, 11) of an identical size.

Abstract: There is provided a hydraulic dumper including an receiving space 15 formed between the rod guide 4 of the cylinder 1 and the insert metal 5 and for temporarily retaining the working fluid leaked out from the oil chamber R1 through the sliding gap of the rod 3, a communicating path 4d for communicating the reservoir R and the receiving space 15, and a check valve 9 for allowing the flow of the working fluid only from the receiving space 15 to the reservoir R, wherein, either one of the lip part 9a of the check valve or the seat surface 4c provided on the rod guide 4 is formed with a sealing projected part 10, 11 protruding from the mutual contact surface.

Abstract: The vibrating device comprises, a vibrating table 3 vibrating upwards and downwards with respect to a vibrating platform 2, and a lower side installation section 4 provided on the vibrating table 3 and having a hemispherical recess surface for supporting the lower end section of a hydraulic shock absorber 6. It further comprises: a holding section 5 for pressing and holding the hydraulic shock absorber 6 towards the vibrating table 3; and an upper side installation section 8 for supporting the front end of the piston rod 7 of the hydraulic shock absorber 6. Moreover, the vibrating device further comprises: a universal joint 30 for coupling the vibrating table 3 and the vibrating platform 2, and a restricting member 31 for restricting the movement of the universal joint 30.

Abstract: The vibrating device comprises, a vibrating table 3 vibrating upwards and downwards with respect to a vibrating platform 2, and a lower side installation section 4 provided on the vibrating table 3 and having a hemispherical recess surface for supporting the lower end section of a hydraulic shock absorber 6. It further comprises: a holding section 5 for pressing and holding the hydraulic shock absorber 6 towards the vibrating table 3; and an upper side installation section 8 for supporting the front end of the piston rod 7 of the hydraulic shock absorber 6. Moreover, the vibrating device further comprises: a universal joint 30 for coupling the vibrating table 3 and the vibrating platform 2, and a restricting member 31 for restricting the movement of the universal joint 30.