Abstract: In an oil-free type screw compressor including a low-pressure-stage compressor main body and a high-pressure-stage compressor main body, when the power of an motor is transmitted to an oil pump via a gear to start the pump, the lubrication oil stored in an oil sump formed at the bottom of a gear casing flows through an oil strainer. A part of the oil is introduced to an oil cooler, while the rest is introduced to a junction portion by bypassing the oil cooler. Further, a part of the oil introduced to the oil cooler is directed to the junction portion. After adjusting the temperature of the oil appropriately, it is introduced to a lubrication portion of the compressor, while the oil cooled by the oil cooler using the full capacity thereof is introduced to oil jackets of the compressor main bodies via different passages.

Abstract: In an oil-free type screw compressor including a low-pressure-stage compressor main body and a high-pressure-stage compressor main body, when the power of an motor is transmitted to an oil pump via a gear to start the pump, the lubrication oil stored in an oil sump formed at the bottom of a gear casing flows through an oil strainer. A part of the oil is introduced to an oil cooler, while the rest is introduced to a junction portion by bypassing the oil cooler. Further, a part of the oil introduced to the oil cooler is directed to the junction portion. After adjusting the temperature of the oil appropriately, it is introduced to a lubrication portion of the compressor, while the oil cooled by the oil cooler using the full capacity thereof is introduced to oil jackets of the compressor main bodies via different passages.

Abstract: A fuel cell stack has an air chamber to which is introduced compressed air that is produced by compressing the atmosphere with a compressor. Energy is recovered from exhaust discharged from the air chamber as it is expanded by an expander. The compressor and the expander are connected to each other via the air chamber of the fuel cell stack through piping. The pressure of the exhaust flowing through the piping is detected by a pressure sensor and, based on the detected pressure, a throttle valve controls a flow rate of the exhaust drawn into the expander.

Abstract: A screw compressor includes a compressor main body, a male rotor having a screw-like male tooth shape and a female rotor having a screw-like female tooth shape meshing with the screw-like male tooth shape or the male rotor. The male and female motors are provided within the compressor main body. A motor casing is operably connected to the compressor main body, and a high speed electric motor provided within the motor casing. The motor includes a motor rotor, a motor stator and a motor shaft for driving at least one of the male and female rotors. A speed ratio of the motor shaft and the at least one of the male and female rotors driven by the motor shaft is in a range of 2:1 to 1:2.

Abstract: An oil free screw compressor includes a compressor main body directly connected to a high speed motor via a drive side gear and a driven side gear having a uniform speed ratio. A bearing in a side of the high speed motor employs one having the same size as that of a bearing in a side of the compressor main body. The same material as a viscous seal provided at both end portions of a male rotor and a female rotor is used for a viscous seal provided at both end portions of a motor shaft. The high speed motor is driven by a high frequency type inverter. The electric motor side and the compressor main body side are made in a rotational shaft structure which is dummy symmetrical about a uniform gear portion.

Abstract: In a capacity control method for an oil-free screw compressor, when an air consumption is larger than a set amount, a rotation frequency of a motor using an inverter to drive the compressor is set to be variable. When the air consumption is a set air amount or less, the inverter is controlled in such a manner that the rotation frequency of the motor is kept at a constant value. In this state, when an operation gas pressure of the compressor reaches an upper-limit value, an air release valve is opened to discharge the operation gas to the atmosphere. Additionally, the rotation frequency of the motor is lowered to a lower-limit value. Re-compression in the compressor can be prevented, and a compressor drive torque is lowered.

Abstract: It is an object of the present invention to provide a touch mode capacitive pressure sensor having higher pressure durability than conventional sensors. In this invention, a touch mode capacitive pressure sensor has a diaphragm made from boron-doped silicon, and the boron concentration at the top face of the diaphragm is equal to or greater than 1×1019 cm−3 and less than 9×1019 cm−3. Further, in this invention, a touch mode capacitive pressure sensor has a conductive diaphragm made by doping of an impurity and anisotropic etching, and the etch pit density on the top face of the diaphragm is equal to or less than five per &mgr;m2, and preferably equal to or less than one per &mgr;m2. As a result, the pressure durability of the diaphragm is greatly improved.

Abstract: An oil free screw compressor having a low-pressure stage compressor body and a high-pressure stage compressor body. Power of a motor driven by an inverter is transmitted to the compressor bodies through gears. A low-pressure stage blow-off two-way valve is provided in a pipe branching off midway an air pipe connecting between the high-pressure stage compressor body and the low-pressure stage compressor body, and a high-pressure stage blow-off two-way valve is provided in a pipe branching off from a discharge air pipe provided on a discharge side of the high-pressure stage compressor body. During no-load operation, a controller gives a command to the inverter to make the rotational speed of the motor a set lower limit rotational speed, and also gives an open command to the low-pressure stage blow-off two-way valve.

Abstract: A capacitance pressure sensor that prevents leakage from outside the sensor to the reference pressure cavity, has a structure that can decrease defects due to leakage compared to conventional technology. An electrode comprising a thin metallic layer is formed on the upper surface of a glass substrate that forms one of the substrates of a pressure sensor and an external electrode is formed on the surface edge of the substrate. In addition, in the region where the silicon substrate is bonded, a feedthrough extending from the electrode to the external electrode is formed, and spine shaped layers with three braches for blocking leakage gas are formed perpendicularly to the feedthrough.

Abstract: An oil free screw compressor includes a compressor main body directly connected to a high speed motor via a drive side gear and a driven side gear having a uniform speed ratio. A bearing in a side of the high speed motor employs one having the same size as that of a bearing in a side of the compressor main body. The same material as a viscous seal provided at both end portions of a male rotor and a female rotor is used for a viscous seal provided at both end portions of a motor shaft. The high speed motor is driven by a high frequency type inverter. The electric motor side and the compressor main body side are made in a rotational shaft structure which is dummy symmetrical about a uniform gear portion.

Abstract: An oil free screw compressor includes a compressor main body directly connected to a high speed motor via a drive side gear and a driven side gear having a uniform speed ratio. A bearing in a side of the high speed motor employs one having the same size as that of a bearing in a side of the compressor main body. The same material as a viscous seal provided at both end portions of a male rotor and a female rotor is used for a viscous seal provided at both end portions of a motor shaft. The high speed motor is driven by a high frequency type inverter. The electric motor side and the compressor main body side are made in a rotational shaft structure which is dummy symmetrical about a uniform gear portion. In the oil free screw compressor, a speed increasing apparatus for increasing an output of an electric motor and a suction throttle valve are not required. Then, parts in the compressor main body side and parts in the electric motor side are made common, and a structure is made simple.

Abstract: An object of the present invention is to provide an iron base Si--Mn alloy or an iron base Si--Mn--Ni alloy which can be easily crushed and can be manufactured in large quantity, and alloy powder thereof.An iron base Si--Mn--Ni alloy having good crushability and alloy powder thereof, comprising:C: 0.40 to 1.20% by weight,Si: 5.0 to 12.0% by weight,Mn: 19.0 to 42.0 % by weight, or Ni: not more than 30% by weight, and the balance being Fe, with the following equations satisfied: Si.gtoreq.11.89-2.92 C-0.077 Mn, Vickers hardness (Hv).gtoreq.550, and area ratio of dendrite structure .ltoreq.50%.An iron base Si--Mn--Ni alloy having good crushability and alloy powder thereof, comprising:C: 0.40 to 1.20% by weight,Si: 5.0 to 12.0% by weight,Mn: 19.0 to 42.0% by weight, or Ni: not more than 30% by weight, and the balance being Fe, with the following equations satisfied: Si.ltoreq.8.3 C+0.14 Mn, and relative permeability (.mu.).ltoreq.1.10.

Abstract: A high-performance angular velocity sensor has a tuning-fork structure in which two vibrator units consisting of piezoelectric elements are coupled to each other. The angular velocity sensor comprises two metal plates, a first vibrator including a first actuator and a first detector joined orthogonally to each other, and a second vibrator including a second actuator and a second detector joined orthogonally to each other, the two vibrators being coupled by an electrode block to each other in parallel along an axis of detection. The first actuator and the first detector include piezoelectric elements bonded to the first metal surface, and the second actuator and the second detector include piezoelectric elements bonded to the second metal surface.

Abstract: The visual line detection device according to the present invention is capable of accurately detecting the visual line of the eyeball of an observer, even though it uses light sources which are only a finite distance away from the eyeball, i.e. which are not effectively at infinity. At least two infrared light emitting diodes are provided for illuminating the eyeball, and the position of the center of curvature of the cornea of the eyeball is obtained based upon the positions of a plurality of images generated by the light rays emitted by these diodes being reflected from the cornea. The direction of the visual line of the eyeball is then calculated using this position of the center of curvature of the cornea. A camera according to the present invention is also disclosed which incorporates such a visual line detection device.

Abstract: An eye-gaze detecting apparatus is constructed as an independent adapter component, which is detachably mounted onto a camera body and which has information reflecting individual differences among observers for proper eye-gaze detection. An eye-gaze detecting adapter has an illuminating device for illuminating an eyeball of observer, an illumination drive device for driving the illumination device, an observing device for observing the eyeball of observer illuminated by the illuminating device, an observation drive device for driving the observing device, a ROM having information necessary for eye-gaze detection, a CPU for calculating an eye-gaze direction of observer with reference to the information from ROM, and a communication device for transmitting the information of eye-gaze direction obtained by the CPU to a camera body.

Abstract: An angular velocity sensor having a tuning-fork structure comprising a first vibrator including a first actuator and a first detector each attached to a metal plate and joined orthogonally to each other, and a second vibrator including a second actuator and a second detector each attached to another metal plate and joined orthogonally to each other, the two vibrators being coupled by an electrode block to each other in a generally parallel relationship along the axis of detection of the sensor. The first and second detectors have a rectangular plate shape each holding a piezoelectric element. The rectangular plate shape has a lengthwise edge and a widthwise edge where the lengthwise edge parallel to the axis of detection of the sensor and is longer than the width wise edge. At least one of the lengthwise edges of the detectors has a beveled surface formed by removing metal at an angle from the lengthwise edge of the detector to balance the sensor.

Abstract: A visual line detecting device having an eyeball lighting unit that irradiates the eyeball of a viewer with a luminous flux, and a visual line detecting unit that detects the visual line of a viewer from the reflected image on the cornea surface of the eyeball, wherein the eyeball lighting unit is designed so that the reflected image on the cornea surface attains a specified shape.

Abstract: An induction heating type cooking appliance is adapted to heat a pan by induction heating. An input unit includes touch control keys and has a timer function so that the power supply is turned on only when at least two keys are actuated properly within a given length of time. Alarms are operatively associated with the timer function so as to alert the operator automatically when the pan is shifted or the appliance is operated under a no-load condition. Such an induction heating type cooking appliance therefore enjoys a high degree of safety.