Abstract: The radial foil bearing (3, 20) includes, a cylindrical top foil (10, 21), a back foil (11) disposed on a radially outer side of the top foil (10, 21), and a cylindrical bearing housing (12, 25) accommodating the top foil (10, 21) and the back foil (11). The top foil (10, 21) is formed by winding a rectangular metal foil around a rotary shaft (1) in a circumferential direction thereof. The metal foil includes a first uneven portion (17a, 23a) which has a first projecting portion (15a, 22a) and a first depressed portion (16a, 23a) on a first side thereof, and a second uneven portion (17b, 24b) which has a second projecting portion (15b, 22b) and a second depressed portion (16b, 23b) on a second side opposite to the first side. The metal foil is wound in a cylindrical shape so that the first uneven portion (17a, 23a) and the second uneven portion (17b, 24b) overlap with each other.

Abstract: The present invention relates to a radial foil bearing for supporting a rotary shaft. The radial foil bearing includes a top foil, a back foil, and a bearing housing accommodating the top and back foils. The top foil is formed by winding a rectangular metal foil into a cylindrical shape so that one end of the metal foil is extended out in a tangential direction of a cylinder formed by the metal foil. An engagement groove is formed on an inner circumferential surface of the bearing housing in an axial direction of the bearing housing, and the engagement groove is formed so that a depth direction thereof corresponds to one tangential direction of the cylinder of the top foil. The one end of the top foil engages with the engagement groove.

Abstract: The radial foil bearing includes a top foil, a back foil, and a bearing housing accommodating the top and back foils, and supports a rotary shaft. Engagement grooves are formed on both side surfaces of the bearing housing to extend from the outer circumferential edge to the inner circumferential edge of the side surface. Notches are formed in circumferential edges on both sides of the back foil. A locking member is locked into the engagement grooves of the bearing housing and the notches of the back foil, and includes a pair of engagement legs engaging with the engagement grooves and the notches, and a connection portion connecting the engagement legs together to be disposed near one ends of the engagement legs.

Abstract: A reference vibrator 10 of the present invention includes: a vibrator body 11 configured to mount to a mount 4 in an unbalance measurement device 1 to which a rotary product is mounted at the time of unbalance measurement, in a same mounting state as the rotary product; a vibration generator 12 fixed to the vibrator body 11 and that applies vibrations to the vibrator body 11; and a control unit 13 that controls the vibration generator 12. Because vibration is caused by the vibration generator 12 fixed to the vibrator body 11, repeatability of vibration force is high. This makes it possible to apply vibrations for repeatability check to the unbalance measurement device 1 with an accurate vibration force. Thus, variations in vibration force can be eliminated, and the repeatability of the unbalance measurement device 1 can be properly checked.

Abstract: A thrust-bearing (1) disposed to face a thrust collar provided on a rotary shaft, including: grooves (5) formed at a bearing-surface (4b); a first-groove-group (6A) constituted by a plurality of first-spiral-grooves (6) formed at an inner circumferential side of the bearing-surface (4b); a second-groove-group (7A) constituted by a plurality of second-spiral-grooves (7) formed at an outer circumferential side more than the first-groove-group (6A) and wound in the same direction as the first-spiral-groove (6); and an annular-land-section (8) formed at the side, to which a fluid is drawn, among the inner circumferential more than the first-groove-group (6A) and the outer circumferential more than the second-groove-group (7A), wherein some of the first-spiral-grooves (6) of the first-groove-group (6A) and some of the second-spiral-grooves (7) of the second-groove-group (7A) are in communication with each other via a partial-communication-section (11), at least one side of which is in partial communication with th

Abstract: A foil bearing supports a cylindrical rotary shaft 2, the foil bearing including: a hollow cylindrical outer ring 4 which is supported by a stationary member, and surrounds the rotary shaft with a predetermined gap therebetween; a thin-film-shaped top foil 3a which surrounds the outer surface of the rotary shaft, and of which one circumferential end is fixed to the inner surface of the outer ring; and a back foil 3b which is formed by a thin film sandwiched between the top foil and the inner surface of the outer ring and elastically supporting the top foil. The back foil 3b includes a support portion which comes into contact with the inner surface of the outer ring and is immovable in the circumferential direction, and an elastic portion which is supported by the support portion and is elastically bent in the radial direction by surface pressure from the top foil.

Abstract: Provided is a gear-driven turbo compressor capable of increasing a natural frequency of a shaft by shortening the length of an overhang from a radial bearing to a shaft end, reducing an effort of replacing lubricant and an environmental burden by greatly reducing the amount of the lubricant, and reducing the necessity for maintenance by reducing a problem of the radial bearing caused by depleted materials of the lubricant. The gear-driven turbo compressor includes: a gas bearing 32 which is in communication with a compressed gas compressed by an impeller 16 and rotatably supports both ends of a pinion shaft 13; and an inner gas seal 34 which is positioned between the gas bearing and a thrust collar, maintains the gas bearing to be compressed by the compressed gas, and prevents intrusion of lubricant for gears due to the compressed gas.

Abstract: A foil bearing supports a cylindrical rotary shaft 2, the foil bearing including: a hollow cylindrical outer ring 4 which is supported by a stationary member, and surrounds the rotary shaft with a predetermined gap therebetween; a thin-film-shaped top foil 3a which surrounds the outer surface of the rotary shaft, and of which one circumferential end is fixed to the inner surface of the outer ring; and a back foil 3b which is formed by a thin film sandwiched between the top foil and the inner surface of the outer ring and elastically supporting the top foil. The back foil 3b includes a support portion which comes into contact with the inner surface of the outer ring and is immovable in the circumferential direction, and an elastic portion which is supported by the support portion and is elastically bent in the radial direction by surface pressure from the top foil.

Abstract: A reference vibrator 10 of the present invention includes: a vibrator body 11 configured to mount to a mount 4 in an unbalance measurement device 1 to which a rotary product is mounted at the time of unbalance measurement, in a same mounting state as the rotary product; a vibration generator 12 fixed to the vibrator body 11 and that applies vibrations to the vibrator body 11; and a control unit 13 that controls the vibration generator 12. Because vibration is caused by the vibration generator 12 fixed to the vibrator body 11, repeatability of vibration force is high. This makes it possible to apply vibrations for repeatability check to the unbalance measurement device 1 with an accurate vibration force. Thus, variations in vibration force can be eliminated, and the repeatability of the unbalance measurement device 1 can be properly checked.