Abstract: This invention provides a compound of the formula (I): wherein R1 represents (C1-C6)alkyl; R2 represents a hydrogen atom, a halogen atom, a hydroxy group, (C1-C6)alkyl, (C1-C6)alkoxy, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy-(C1-C6)alkyl or halo(C1-C6)alkyl; R3 represents a halogen atom, (C1-C6)alkyl, (C1-C6)alkoxy, hydroxy(C1-C6)alkoxy, (C1-C6)alkoxy-(C1-C6)alkyl, (C1-C6)alkoxy-(C1-C6)alkoxy, halo(C1-C6)alkyl, (C1-C6)alkylthio, (C1-C6)alkylsulfinyl, (C1-C6)alkylsulfonyl, [(C1-C6)alkyl]NH—, or [(C1-C6)alkyl]2N—; R4 represents a halogen atom, (C1-C6)alkyl, halo(C1-C6)alkyl, (C1-C6)alkoxy, hydroxy(C1-C6)alkoxy, (C1-C6)alkoxy-(C1-C6)alkyl, (C1-C6)alkoxy-(C1-C6)alkoxy, [(C1-C6)alkyl]NH—, or [(C1-C6)alkyl]2N—; R5 represents a halogen atom, (C1-C6)alkyl, (C1-C6)alkoxy, hydroxy(C1-C6)alkoxy, (C1-C6)alkoxy-(C1-C6)alkyl, (C1-C6)alkoxy-(C1-C6)alkoxy, halo(C1-C6)alkyl, (C1-C6)alkylthio, (C1-C6)alkylsulfinyl, (C1-C6)alkylsulfonyl, [(C1-C6)alkyl]NH—, [(C1-C6)alkyl]2N—, H2N—(C1-C6)alkoxy, (C1-C6)alkyl-NH—(C1-C6)alkoxy,

Abstract: A bearing unit is provided which includes a shaft (51) to support rotatably, radial bearing (55) to support the shaft (51) circumferentially, a thrust bearing (66) to support the shaft (51) in the direction of thrusting, and a housing (56) having the radial bearing (55) and thrust bearing (66) disposed therein and in which a viscous fluid (57) is filled. The housing (56) has a sealed structure except for a shaft insertion hole (65) formed therein and through which the shaft 51 is introduced. Between the outer surface of the shaft (51) and the inner surface of the shaft insertion hole (65), there is defined a gap (69) having a sufficient width to prevent the viscous fluid (57) filled in the housing (56) from leaking out of the latter. The housing (56) is formed as a one-piece structure by molding a synthetic resin.

Abstract: Disclosed herein is an automatic balancing device including a balancer made of a magnetic fluid, a rotatable enclosure having an outer circumferential wall and accommodating the balancer, a magnet provided near at least the center of rotation of the enclosure so as to be rotatable integrally with the enclosure, and a platelike projection projecting from the outer circumferential wall toward the center of rotation of the enclosure, at least a part of the platelike projection extending in a direction different from a radial direction of the enclosure at the juncture between the platelike projection and the outer circumferential wall.

Abstract: A bearing unit is provided which includes a shaft (51) to support rotatably, radial bearing (55) to support the shaft (51) circumferentially, a thrust bearing (66) to support the shaft (51) in the direction of thrusting, and a housing (56) having the radial bearing (55) and thrust bearing (66) disposed therein and in which a viscous fluid (57) is filled. The housing (56) has a sealed structure except for a shaft insertion hole (65) formed therein and through which the shaft 51 is introduced. Between the outer surface of the shaft (51) and the inner surface of the shaft insertion hole (65), there is defined a gap (69) having a sufficient width to prevent the viscous fluid (57) filled in the housing (56) from leaking out of the latter. The housing (56) is formed as a one-piece structure by molding a synthetic resin.

Abstract: A bearing unit is provided which supports a shaft (51) rotatably. It includes the shaft (51), a radial bearing (55) to support the shaft (51) circumferentially, a thrust bearing (58) to support the shaft (51) at one of thrusting-directional ends of the latter, a housing (56) having disposed therein the radial bearing (55) and thrust bearing (58) supporting together the shaft (51) and which is filled with a viscous fluid (67), and a spacer member (65) disposed inside the housing (56) to keep a gap defined between the end face of the radial bearing (55) and one side of a radial projection (54) included in the shaft (51). On the end face of the radial breading (55) opposite to one side of the radial projection (54), there is formed a first dynamic pressure producing recess (63) which produces a dynamic pressure by the viscous fluid.

Abstract: A bearing unit is provided which includes a shaft (51) to support rotatably, radial bearing (55) to support the shaft (51) circumferentially, a thrust bearing (66) to support the shaft (51) in the direction of thrusting, and a housing (56) having the radial bearing (55) and thrust bearing (66) disposed therein and in which a viscous fluid (57) is filled. The housing (56) has a sealed structure except for a shaft insertion hole (65) formed therein and through which the shaft 51 is introduced. Between the outer surface of the shaft (51) and the inner surface of the shaft insertion hole (65), there is defined a gap (69) having a sufficient width to prevent the viscous fluid (57) filled in the housing (56) from leaking out of the latter. The housing (56) is formed as a one-piece structure by molding a synthetic resin.

Abstract: A bearing unit is provided which includes a shaft (51) to support rotatably, radial bearing (55) to support the shaft (51) circumferentially, a thrust bearing (66) to support the shaft (51) in the direction of thrusting, and a housing (56) having the radial bearing (55) and thrust bearing (66) disposed therein and in which a viscous fluid (57) is filled. The housing (56) has a sealed structure except for a shaft insertion hole (65) formed therein and through which the shaft 51 is introduced. Between the outer surface of the shaft (51) and the inner surface of the shaft insertion hole (65), there is defined a gap (69) having a sufficient width to prevent the viscous fluid (57) filled in the housing (56) from leaking out of the latter. The housing (56) is formed as a one-piece structure by molding a synthetic resin.

Abstract: A bearing unit is provided which includes a shaft (51) to support rotatably, radial bearing (55) to support the shaft (51) circumferentially, a thrust bearing (66) to support the shaft (51) in the direction of thrusting, and a housing (56) having the radial bearing (55) and thrust bearing (66) disposed therein and in which a viscous fluid (57) is filled. The housing (56) has a sealed structure except for a shaft insertion hole (65) formed therein and through which the shaft 51 is introduced. Between the outer surface of the shaft (51) and the inner surface of the shaft insertion hole (65), there is defined a gap (69) having a sufficient width to prevent the viscous fluid (57) filled in the housing (56) from leaking out of the latter. The housing (56) is formed as a one-piece structure by molding a synthetic resin.

Abstract: An automatic balancing apparatus includes a balancer made of a magnetic fluid, a housing member rotatably provided and for housing the balancer, and a flat magnet disposed integrally rotatable within the housing member and to extend from a center of rotation to an outer circumferential side of the housing member. Accordingly, the automatic balancing apparatus can start rotating with the balancer held by the magnet irrespective of the attitude of the automatic balancing apparatus, whereby the balance of rotation can be improved in a stable manner.

Abstract: The bearing unit of the present invention has: a shaft; a radial bearing which supports the shaft in a circumferential direction of the shaft; a thrust bearing which supports an end of the shaft in a thrust direction of the shaft; a housing having a closed structure except for a shaft insertion hole in which the shaft is inserted, with the radial bearing and the thrust bearing being provided inside the housing; a stopper member which prevents the shaft from being pulled out of the radial bearing; and viscous liquid filled in the housing. The stopper member is made of an elastic member which is elastically deformed only in the radial direction and is hardly deformed in the axial direction. Hence, the shaft is prevented from being pulled out from the housing, and shortage of the lubrication oil around bearing surfaces is prevented from being caused by lifting of the shaft.

Abstract: The present invention relates to bearing unit for supporting a shaft 2 so as to freely rotate and includes a radial bearing 4 for supporting the shaft 2 so as to freely rotate and a housing member 6 made of a resin for holding the radial bearing 4. The housing member 6 is formed with a material having a coefficient of thermal contraction larger than that of a material used for the radial bearing 4. Assuming that the radial thickness of the radial bearing 4 is m and the radial thickness of a housing main body part of the housing member 6 with which the outer periphery of the radial bearing is covered is n, a relation of m>n is satisfied. Thus, an influence due to a thermal contraction upon molding is prevented from being applied to the radial bearing.

Abstract: A bearing unit (90) for rotatably supporting a shaft (100) comprises a seamless holding member (120) with a gap allowing a shaft to run through and extend to the outside, a bearing (130) arranged in the inside of the holding member to rotatably support the shaft so as to make it radially revolvable, an anti-shaft-release member (115) fitted to the shaft so as to abut the bearing in order to prevent the shaft from slipping away in the thrusting direction and a space-forming member (113) arranged in the inside of the holding member so as to secure a space around the anti-shaft-release member. A bearing unit may further comprise an lubricating oil seal member and the space-forming member may be used to form a passage way for lubricating oil to prevent lubricating oil from leaking.

Abstract: A bearing unit comprises a shaft, a radial bearing for supporting the shaft in a peripheral rotation direction of the shaft, a thrust bearing supporting an end of the shaft in a thrust direction of the shaft, a housing made of a molded body of a synthetic resin, inside of which housing the radial bearing and the thrust bearing are arranged, the housing having a sealed configuration except for a shaft insertion hole, through which the shaft is inserted, a slip-out preventing member provided on an end side of the radial bearing at which the thrust bearing is provided, the slip-out preventing member preventing the shaft from slipping out from the radial bearing, and a viscous fluid filled in the housing. The slip-out preventing member is made of a material having a thermal deformation temperature higher than a temperature applied to the slip-out preventing member upon molding of the housing.

Abstract: It is an object of the present invention to provide a hydrodynamic pressure bearing type pump in which a shaft can freely rotate in the radial direction and in which a hydrodynamic pressure bearing can reliably generate fluid pumping pressure, the hydrodynamic pressure bearing type pump being miniaturized. To this end, the hydrodynamic pressure bearing type pump comprises a rotating portion 121 located in a fluid flow passage within a main body for generating hydrodynamic pressure to let fluid flow into a fluid flow inlet 11 and to let fluid flow from a fluid flow outlet 12 to the outside, the rotating portion 121 including a shaft 14, a hydrodynamic pressure bearing 13 for generating hydrodynamic pressure to let fluid flow into the fluid flow inlet and to let fluid flow from the fluid flow outlet to the outside when the shaft is rotated and a rotation force generating portion 133 disposed within the main body and rotating the shaft when it is energized.

Abstract: A reliable bearing unit, in which lubricant does not leak and the problem of shaft lifting at the time of the rotation of a rotor due to the imbalance of a pair of dynamic pressure generating grooves can be surely and inexpensively solved, and a rotary drive apparatus including the bearing unit are provided.

Abstract: The processing method of the grooves and the processing apparatus of the present invention do not utilize the elastic deformation of a bearing itself, and by inserting the pin into the cylindrical-shaped core rod which is inserted into the inner circumference of the cylindrical-shaped bearing material, the cylindrical-shaped core rod is depressed against the inner circumference surface of the cylindrical-shaped bearing material and the concavoconvex of the outer circumference of the cylindrical-shaped core rod is transfer-printed on the inner circumference of the cylindrical-shaped bearing material.

Abstract: A fan motor having a small thickness and its impeller's blades are formed to have a longer length in the diametral direction than a width in the axial direction. Since the blade of the fan motor has a tooth structure or chamfers at its edge end in the diametral direction, turbulence is forcibly evoked in an airflow to promote the turbulent diffusion, thereby suppressing the trailing vortex and reducing the aerodynamic noises, thus the ventilation efficiency is improved.

Abstract: A friction material having a good balance of properties is made by molding and curing a composition which contains a fibrous base, a binder and a filler, and includes a specific combined amount of at least three types of metal oxide having Mohs hardnesses of 4 to 6.5. The friction material suppresses low-frequency noise generation, minimizes rotor and disc pad wear, and has a high and stable coefficient of friction at high speeds.

Abstract: A structure for securing a spindle motor (15) supported on a motor substrate (32) to a chassis (13). The motor substrate (32) and the chassis (13) are coupled by at least three coupling sections (33). At least two of the coupling sections (33) are fixed support members (33a) which hold and space the motor substrate (32) and the chassis (13) from each other at a prescribed distance. The remaining coupling section is an adjusting support member (33b) that holds the motor substrate (32) and the chassis (13) from each other at a variable distance. Rigid holding means is incorporated in the adjusting support member (33b) and holds the motor substrate (32) and the chassis (13) so that the motor substrate (32) and the chassis (13) remain rigid.

Abstract: An objective lens drive device (8) includes a supporting block (9), a movable block (10) for holding an objective lens (27), and supporting springs (22) for connecting the supporting block and the movable block. Elements of the supporting block of the objective lens drive device (8) are a stationary section (11), a supporting shaft (12), a tilt drive section (13), and tilt drive magnetic circuits (20 and 20). The stationary section (11) is secured to a movable base (7) that is movable in radial directions of a disc-shaped recording medium (100). An axial direction of the supporting shaft (12) is perpendicular to both focusing directions and tracking directions. The tilt drive section (13) is rotatably supported at the stationary section through the supporting shaft and is connected to the movable block through the supporting springs. The tilt drive magnetic circuits (20 and 20) are used to rotate the tilt drive section with respect to the stationary section.