Abstract: The present invention provides a method of producing a silicon carbide semiconductor substrate in which a silicon carbide buffer layer doped with germanium and a semiconductor device layer are sequentially laminated on the buffer layer, a silicon carbide semiconductor substrate obtained by the method and a silicon carbide semiconductor in which electrodes are disposed on the silicon carbide semiconductor substrate.

Abstract: A channel layer (40) for forming a portion of a carrier path between a source electrode (100) and a drain electrode (110) is formed on a drift layer (30). The channel layer (40) includes Ge granular crystals formed on the drift layer (30), and a cap layer covering the Ge granular crystals.

Abstract: A channel layer (40) for forming a portion of a carrier path between a source electrode (100) and a drain electrode (110) is formed on a drift layer (30). The channel layer (40) includes Ge granular crystals formed on the drift layer (30), and a cap layer covering the Ge granular crystals.

Abstract: A semiconductor material having a stepwise surface structure of (0001)-plane terraces and (11-2n)-plane steps [n?0] on the SiC substrate, a semiconductor device using the same and a method of producing the semiconductor material in which a carbon-rich surface is formed on the SiC substrate prior to epitaxial growth of an SiC crystal, the carbon-rich surface satisfies the ratio R=(I284.5/I282.8)>0.2, wherein I282.8 (ISiC) is an integrated intensity of a C1s signal having a peak at the binding energy relating to stoichiometric SiC (in the region of 282.8 eV), and I284.5 (IC) is an integrated intensity of a C1s signal having a peak at the binding energy relating to graphite, SiCx (x>1), or SiyCH1-y (y<1) (in the region of 284.5 eV), as measured by an X-ray photoelectron spectroscopic analyzer (XPS).

Abstract: A semiconductor material having a stepwise surface structure of (0001)-plane terraces and (11-2n)-plane steps [n?0] on the SiC substrate, a semiconductor device using the same and a method of producing the semiconductor material in which a carbon-rich surface is formed on the SiC substrate prior to epitaxial growth of an SiC crystal, the carbon-rich surface satisfies the ratio R=(I284.5/I282.8)>0.2, wherein I282.8 (ISiC) is an integrated intensity of a C1s signal having a peak at the binding energy relating to stoichiometric SiC (in the region of 282.8 eV), and I284.5 (IC) is an integrated intensity of a C1s signal having a peak at the binding energy relating to graphite, SiCx (x>1), or SiyCH1-y (y<1) (in the region of 284.5 eV), as measured by an X-ray photoelectron spectroscopic analyzer (XPS).

Abstract: The present invention provides a method of producing a silicon carbide semiconductor substrate in which a silicon carbide buffer layer doped with germanium and a semiconductor device layer are sequentially laminated on the buffer layer, a silicon carbide semiconductor substrate obtained by the method and a silicon carbide semiconductor in which electrodes are disposed on the silicon carbide semiconductor substrate.

Abstract: A mechanical supercharger includes a housing, first, second and third shafts rotatably supported on the housing, respectively, a first timing gear disposed on the first shaft, a second timing gear disposed on the second shaft and engaged with the first shaft timing gear, a first rotor disposed on the first shaft, a second rotor disposed on the second shaft and engaged with the first rotor, a first pulley disposed on one end of the first shaft, an electromagnetic clutch interposed between the first shaft and the first pulley and being selectively intermittent a transmission of driving force between the first shaft and the first pulley, a reduction gear disposed on one end of the third shaft through an one-way clutch and engaged with the second timing gear, a second pulley disposed on the other end of the third shaft and a driving force transmission means for transmitting driving force of engine to the first and second pulleies so that the first and second pulleies are simultaneously rotated in the same directi

Abstract: An engine has an air supply passage and an exhaust gas passage. A supercharger and a turbocharger compressor are disposed in the air supply passage. The turbocharger compressor is disposed downstream of the supercharger and is driven by a turbocharger turbine disposed in the exhaust gas passage. A valved air by-pass is provided for conducting air around the supercharger between the supercharger outlet and inlet. A valved exhaust gas by-pass is provided for conducting exhaust gas around the turbine. During engine low speed operation the air by-pass and exhaust gas by-pass are closed and air is compressed by both the supercharger and compressor acting in series. During an intermediate speed range, the air by-pass is partially opened under the control of the air pressure at the compressor outlet to assure that such air pressure does not exceed a preset value.

Abstract: An austenitic stainless steel having improved free cutting properties is disclosed, which consists essentially of, on a weight ratio, C.ltoreq.0.2%. Si.ltoreq.2.0%, Mn.ltoreq.2.0%, 7.5%.ltoreq.Cr.ltoreq.30.0%, Ni.ltoreq.40.0%, 0.005%.ltoreq.Bi.ltoreq.0.50%, 0.0003%.ltoreq.B.ltoreq.0.10%, 0.002%.ltoreq.S.ltoreq.0.40%, P.ltoreq.0.02%, N.ltoreq.0.05% and/or O.ltoreq.0.005% and the balance being Fe.

Abstract: A supercharged pressure controller for internal combustion engines, which comprises a switch valve for switching negative pressure at a throttle valve to atmospheric pressure and a relief valve operated by the signal from the switch valve to release the supercharged pressure in a surge tank, thereby controlling the supercharged pressure accurately in accordance with various running conditions of vehicle, avoiding inconveniences such as rough idling or knocking of engine.

Abstract: A thrust bearing for an automobile turbocharger and which sustains a thrust load of the rotor shaft of the turbocharger. The thrust bearing has a first groove for holding lubricating oil supplied to the bearing. A first oil passage extends from the groove toward the axis of the rotor shaft. A second oil passage communicates with the first passage and has oil holes formed therein that extend to tapering lands formed on surfaces on which the rotor shaft bears. The second passage is so disposed that oil is spouted on both sides of the bearing. The lower end portion of the bearing is cut out portion to facilitate removal of oil. The cut out portion constitutes a planar portion of a closed loop on a surface of the bearing. A second groove is formed in the thrust bearing to hold oil discharged from the oil holes to some extent.

Abstract: A motor-driven proportional fluid flow control valve has a linear motor including a slide valve body slidably mounted on a hollow iron core and an electromagnetic coil wound around the iron core. After a drive circuit has been energized, a constant current is passed through the electromagnetic coil to keep the slide valve body spaced from a stop surface while cutting off fluid communication between an inlet port and an outlet port. With the slide valve body out of contact with the stop surface, the slide valve does not produce noise which would otherwise be given off due to a fluctuating current flowing, through or vibrations of, the electromagnetic coil.

Abstract: An air-fuel ratio control apparatus includes a specific integration means for integrating the rich or lean signal determined depending upon the detected concentration of the predetermined exhaust gas component, to produce an integration signal which is increased when the rich signal is applied and decreased only when the lean signal, having a duration longer than a predetermined period, is applied. If the short lean signal, having a duration shorter than or equal to the predetermined period, is produced, the above integration signal is utilized for adjusting the air-fuel ratio condition.

Abstract: A diaphragm air pump assembly pneumatically associated with a vacuum source and an atmospheric air source, comprises two diaphragms interconnected by a vertically extending rod to define two vacuum operational chambers and two pump chambers, two valves for controlling the alternative admission of vacuum to the vacuum operational chambers, and two normally closed valves operable in response to movement of the diaphragms in unison with the rod, each of two corresponding constituent parts being disposed and mounted in a symmetrical arrangement with respect to the central axis of the pump assembly. When the diaphragms are moved in one direction, one of two normally closed valves is opened to admit the vacuum into one of two vacuum operational chambers while admitting atmospheric air into the other vacuum operational chamber.

Abstract: A diaphragm air pump assembly in pneumatic association with a vacuum source and an atmospheric air source includes therein two vacuum operational chambers and two pump chambers defined by two interconnected diaphragms upon admission of vacuum to one of the vacuum operated chambers and atmospheric air to the other vacuum operated chamber the diaphragms are moved in one direction due to pressure difference thereby compressing and exhausting the air contained in one of the pump chambers as well as opening one of two normally closed valves. The vacuum is thus admitted into the other vacuum operational chamber while atmospheric air is supplied to one vacuum operated chamber, so that the diaphragms are moved in the other direction thereby compressing and exhausting the air contained in the other pump chamber as well as opening the other normally closed valve. A periodical reciprocation of the diaphragms will accomplish the pumping operation.

Abstract: A steel which is suitable for the material of a mold used for plastic molding and which has an improved resistance to corrosion under exposure to a halogen gas generated in injection molding of a thermoplastic synthetic resin blended with a halogen-containing flame-retarding agent is obtained by shaping a steel which consists essentially of up to 0.05% carbon, up to 1.0% silicon, up to 2.0% manganese, 5.0-8.0% nickel, 11.0-15.0% chromium, 1.0-4.0% molybdenum, 0.5-4.0% copper, 0.5-2.0% cobalt and the balance iron into a mold, and then subjecting the mold to age-hardening treatment at a temperature in the range of 400.degree.-450.degree. C. to obtain a hardness of H.sub.R C 30 or higher. The steel may further contain a small, predetermined amount of at least one machinability-improving component such as lead, tellurium, calcium and bismuth and/or a small, predetermined amount of at least one toughness or hardness-improving component such as tungsten, boron, titanium, vanadium, niobium and tantalum.