Abstract: A process for assembling to a knuckle member a bearing unit for driving wheels including a hub, a bearing, and a constant velocity universal joint is simplified. In order to achieve this, a hub (10) and an outer joint member (31) of an out-board side constant velocity universal joint (30) are plastically joined together. An outer peripheral surface (26a) of an outer member (26) is press-fitted into an inner peripheral surface of the knuckle member, and a maximum diameter dimension (D1) of the out-board side constant velocity universal joint (30) is set smaller than a minimum diameter dimension (Dn) of the knuckle member (6). Also, a maximum diameter dimension (D2) of an in-board side constant velocity universal joint (40) is set smaller than the minimum diameter dimension (Dn) of the knuckle member (6).

Abstract: A field effect transistor includes: a first nitride semiconductor layer having a plane perpendicular to a (0001) plane or a plane tilted with respect to the (0001) plane as a main surface; a second nitride semiconductor layer formed on the first nitride semiconductor layer and having a wider bandgap than the first nitride semiconductor layer; a third nitride semiconductor layer formed on the second nitride semiconductor layer; and a source electrode and a drain electrode formed so as to contact at least a part of the second nitride semiconductor layer or the third nitride semiconductor layer. A recess that exposes a part of the second nitride semiconductor layer is formed between the source electrode and the drain electrode in the third nitride semiconductor layer. A gate electrode is formed in the recess and an insulating film is formed between the third nitride semiconductor layer and the gate electrode.

Abstract: A semiconductor device includes: a first semiconductor layer which is made of a first group III nitride semiconductor; a cap layer which is formed on the first semiconductor layer, which is made of a second group III nitride semiconductor, and which has an opening for exposing the first semiconductor layer; and a source electrode and a drain electrode which are formed on the cap layer so as to oppose to each other with the opening interposed. A gate electrode is formed on the bottom face of the opening with an insulating film interposed. The insulating film is formed on at least a part of the first semiconductor layer which is exposed through the opening.

Abstract: It is an object of the present invention to provide a nitride semiconductor device with low parasitic resistance by lowering barrier height to reduce contact resistance at an interface of semiconductor and metal. The nitride semiconductor device includes a GaN layer, a device isolation layer, an ohmic electrode, an n-type Al0.25Ga0.75N layer, a sapphire substrate, and a buffer layer. A main surface of the n-type Al0.25Ga0.75N layer is on (0001) plane as a main surface, and concaves are arranged in a checkerboard pattern on the surface. The ohmic electrode contacts the sides of the concaves of the n-type Al0.25Ga0.75N layer, and the sides of the concaves are on non-polar surfaces such as (11-20) plane or (1-100) plane.

Abstract: An object of the present invention is to provide a normally-off type field effect transistor which includes: a first semiconductor layer which is made of a first hexagonal crystal with 6 mm symmetry and has a main surface including a C-axis of the first hexagonal crystal; a second semiconductor layer which is formed on the main surface of the first semiconductor layer and is made of a second hexagonal crystal with 6 mm symmetry having a band gap different from a band gap of the first hexagonal crystal; and a gate electrode, a source electrode and drain electrode that are formed on the second semiconductor layer. Here, the film thickness of the first nitride semiconductor layer is 1.5 ?m or less and the second semiconductor layer is doped with impurities at a dose of 1×1013 cm?2 or more.

Abstract: An object of the present invention is to provide a semiconductor device and a manufacturing method thereof which can realize a normally-off field-effect transistor made of a III group nitride semiconductor. The present invention includes: placing a sapphire substrate in a crystal growth chamber; forming a low-temperature GaN buffer layer made of GaN as the III group nitride semiconductor, on a main surface of the sapphire substrate by a MOCVD method; and forming a GaN layer on the low-temperature GaN buffer layer by the MOCVD method. Here, a [11-20] axis of the GaN layer is perpendicular to the main surface of the sapphire substrate.

Abstract: A constant velocity joint including an outer joint member formed with three track grooves having roller guide surfaces arranged in circumferentially opposed relation to each other; a tripod member having three radially projecting leg shafts; a plurality of rollers inserted in the track grooves; and a ring fitted directly on each of the leg shafts to support the rollers for rotation, the rollers being movable along the roller guide surfaces axially of the outer joint member, wherein each roller includes a set of annular roller portions and a plurality of balls interposed between outer raceway surfaces formed in rows in an inner periphery of the annular roller portions and two rows of inner raceway surfaces formed in an outer periphery of the ring, and wherein the inner peripheral surface of the ring is cylindrical and the outer peripheral surface of the leg shaft is spherical.

Abstract: It is intended that the induced thrust and slide resistance of a constant velocity joint should be further reduced. To this end, there is provided a constant velocity joint comprising an outer joint member having three track grooves each having circumferentially opposed roller guide surfaces, a tripod member having three radially projecting leg shafts, a roller inserted in each track groove, and a ring fitted on each leg shaft to rotatably support the roller, the roller being movable along the roller guide surfaces axially of the outer joint member. The roller includes a set of annular roller segments, with a plurality of balls interposed between outer raceway surfaces formed on the inner periphery of the annular roller segments and a single inner raceway surface formed on the outer periphery of the ring.

Abstract: A tire wheel bearing apparatus comprises an outer member having multi rows of track surfaces integrally provided on an inner periphery, an inner member having a tire wheel mounting flange provided at one end thereof, a cylindrical small diameter step portion provided at another end thereof and double-rows of track surfaces formed on the inner wheels force fitted to the small diameter step portion so as to oppose to the track surfaces of the outer member, and double-rows of rolling elements respectively interposed between the track surfaces in the outer member and the inner member, the inner wheels being fixed to the inner member by radially outwardly caulking the end portion of the small diameter step portion of the inner member, the track surfaces in the outer member and the inner member and the rolling elements has a contact angle with a bearing clearance being set to be negative.

Abstract: A tire wheel bearing apparatus comprises an outer member having multi rows of track surfaces integrally provided on an inner periphery, an inner member having a tire wheel mounting flange provided at one end thereof, a cylindrical small diameter step portion provided at another end thereof and double-rows of track surfaces formed on the inner wheels force fitted to the small diameter step portion so as to oppose to the track surfaces of the outer member, and double-rows of rolling elements respectively interposed between the track surfaces in the outer member and the inner member, the inner wheels being fixed to the inner member by radially outwardly caulking the end portion of the small diameter step portion of the inner member, the track surfaces in the outer member and the inner member and the rolling elements has a contact angle with a bearing clearance being set to be negative.

Abstract: A constant velocity universal joint comprises an outer joint member 10 formed with three track grooves 12 having roller guide surfaces 14 arranged in circumferentially opposed relation to each other, a tripod member 20 having three radially projecting trunnions 22, rollers 34 inserted in the track grooves 12, and rings 32 fitted on the trunnions 22 to support the rollers 34 for rotation, the rollers 34 being movable along the roller guide surfaces 14 axially of the outer joint member 10, wherein the roller 34 is composed of a set of annular roller portions 34a and 34b and a plurality of balls 36 are interposed between outer raceway surfaces formed in rows each in the inner periphery of the annular roller portion 34 and two rows of inner raceway surfaces formed in the outer periphery of the ring 32.

Abstract: A constant velocity universal joint comprises an outer joint member 10 formed with three track grooves 12 having roller guide surfaces 14 arranged in circumferentially opposed relation to each other, a tripod member 20 having three radially projecting trunnions 22, rollers 34 inserted in the track grooves 12, and rings 32 fitted on the trunnions 22 to support the rollers 34 for rotation, the rollers 34 being movable along the roller guide surfaces 14 axially of the outer joint member 10, wherein the roller 34 is composed of a set of annular roller portions 34a and 34b and a plurality of balls 36 are interposed between outer raceway surfaces formed in rows each in the inner periphery of the annular roller portion 34 and two rows of inner raceway surfaces formed in the outer periphery of the ring 32.

Abstract: A tire wheel bearing apparatus comprises an outer member having multi rows of track surfaces integrally provided on an inner periphery, an inner member having a tire wheel mounting flange provided at one end thereof, a cylindrical small diameter step portion provided at another end thereof and double-rows of track surfaces formed on the inner wheels force fitted to the small diameter step portion so as to oppose to the track surfaces of the outer member, and double-rows of rolling elements respectively interposed between the track surfaces in the outer member and the inner member, the inner wheels being fixed to the inner member by radially outwardly caulking the end portion of the small diameter step portion of the inner member, the track surfaces in the outer member and the inner member and the rolling elements has a contact angle with a bearing clearance being set to be negative.

Abstract: A tire wheel bearing apparatus comprises an outer member having multi rows of track surfaces integrally provided on an inner periphery, an inner member having a tire wheel mounting flange provided at one end thereof, a cylindrical small diameter step portion provided at another end thereof and double-rows of track surfaces formed on the inner wheels force fitted to the small diameter step portion so as to oppose to the track surfaces of the outer member, and double-rows of rolling elements respectively interposed between the track surfaces in the outer member and the inner member, the inner wheels being fixed to the inner member by radially outwardly caulking the end portion of the small diameter step portion of the inner member, the track surfaces in the outer member and the inner member and the rolling elements has a contact angle with a bearing clearance being set to be negative.

Abstract: A tire wheel bearing apparatus comprises an outer member having multi rows of track surfaces integrally provided on an inner periphery, an inner member having a tire wheel mounting flange provided at one end thereof, a cylindrical small diameter step portion provided at another end thereof and double-rows of track surfaces formed on the inner wheels force fitted to the small diameter step portion so as to oppose to the track surfaces of the outer member, and double-rows of rolling elements respectively interposed between the track surfaces in the outer member and the inner member, the inner wheels being fixed to the inner member by radially outwardly caulking the end portion of the small diameter step portion of the inner member, the track surfaces in the outer member and the inner member and the rolling elements has a contact angle with a bearing clearance being set to be negative.

Abstract: It is intended that the induced thrust and slide resistance of a constant velocity joint should be further reduce.

Abstract: A constant velocity universal joint with a further reduction in inductive thrust and slide resistance. The constant velocity universal joint comprises: an outer joint member 10 having three track grooves 12 each having circumferentially-opposed roller guideways 14; a tripod member 20 having three radially-projecting trunnions 22; a roller 34 inserted in each of the track grooves 12; and a ring 32 fitted on each of the trunnions 22 to support the roller 34 rotatably, the roller 34 being movable in axial directions of the outer joint member 1 along the roller guideways 14. Here, the inner periphery of the ring 32 is shaped arcuate and convex in section. The outer periphery of each of the trunnions 22 is shaped straight in longitudinal section, as well as formed in cross section so as to make a contact with the inner periphery of the ring 32 along a direction perpendicular to the axis of the joint and create a clearance with the inner periphery of the ring 32 in an axial direction of the joint.

Abstract: A constant velocity universal joint comprises an outer joint member 10 formed with three track grooves 12 having roller guide surfaces 14 arranged in circumferentially opposed relation to each other, a tripod member 20 having three radially projecting trunnions 22, rollers 34 inserted in the track grooves 12, and rings 32 fitted on the trunnions 22 to support the rollers 34 for rotation, the rollers 34 being movable along the roller guide surfaces 14 axially of the outer joint member 10, wherein the roller 34 is composed of a set of annular roller portions 34a and 34b and a plurality of balls 36 are interposed between outer raceway surfaces formed in rows each in the inner periphery of the annular roller portion 34 and two rows of inner raceway surfaces formed in the outer periphery of the ring 32.

Abstract: A dual component mixing system for coating comprises a first tank containing a main agent, a second tank containing a hardening agent diluted with thinner, a mixer which mixes the main agent and the hardening agent and supplies the mixture to a manually operated coating gun, a main agent line connecting the mixer and the first tank, a hardening agent line connecting the mixer and the second tank, a flow meter disposed within the main agent line, a flow meter and a flow regulating valve disposed within the hardening agent line, and a feedback control device which receives signals from the flow meters and controls the flow regulating valve so that the amount of hardening agent is a predetermined ratio with respect to the amount of main agent. The dual component mixing system according to the present invention provides an adequate control of the main agent/hardening agent ratio regardless of the differences among individuals manipulating the coating gun.

Abstract: A flying head slider for use in a hard disk drive includes a slider body having pair of parallel slider rails spaced from each other with a slider groove defined therebetween. A magnetic head is supported on one of the slider rails. The slider body also has a pair of control grooves disposed on one side of the slider rails, respectively, and extending therealong. The control grooves are shallower than the slider groove. The flying head slider floats off the surface of a hard disk stably by a low height over an entire disk surface range.