Abstract: A turbo-molecular pump evacuates gas with a rotor that rotates at a high speed. The turbo-molecular pump comprises a casing, a stator fixedly mounted in the casing and having stator blades, a rotor rotatably provided in the casing and having rotor blades alternating with the stator blades, and a radial turbine blade pumping section having a spiral ridge-groove section provided on at least one of surfaces, facing each other, of the stator blade and the rotor blade. At least one of the stator blade and the rotor blade which are located at a first stage of the radial turbine blade pumping section has such a shape that at least one of the stator blade and the rotor blade is smaller in thickness in a direction of gas flow.

Abstract: A gas recirculation flow control method and apparatus for use in an evacuation system having a vacuum chamber into which a gas is introduced, a first vacuum pump for exhausting the gas from the vacuum chamber and reducing the pressure in the vacuum chamber to a desired pressure, a second vacuum pump for performing evacuation to lower the back pressure of the first vacuum pump below an allowable back pressure, and a gas recirculation line for returning a part of gas exhausted from the first vacuum pump to the vacuum chamber.

Abstract: A tire air pressure detecting device has a tire air pressure detecting device on a wheel. A main transmitting device is provided at the wheel for transmitting an air pressure signal SP to a vehicle body. A main receiving device is provided at the vehicle body for receiving the air pressure signal SP. A main switch turn-on detecting device is provided on the vehicle body for detecting the turn-on of a main switch. A second control device is provided on the vehicle body for receiving the air pressure signal SP and a main switch ON signal Son. An auxiliary transmitting device on the vehicle body transmits a transmission instruction signal SR to the wheel when the second control means receives the main switch ON signal Son. An auxiliary receiving device on the wheel receives the transmission instruction signal SR. A first control device is provided for reading a new air pressure signal SP. When the main switch is turned on, the state of the tire air pressure can immediately be recognized.

Abstract: A compact turbo-molecular pump has a relatively short axial length and yet provides sufficient evacuation and compression capabilities. The turbo-molecular pump comprises a casing (10) which contains an exhaust vane section (L1) having rotary vanes (30) on a rotor section alternating with stationary vanes (32) on a stator section. The exhaust vane section comprises an axial exhaust vane section (L1) and a radial exhaust vane section (L2) disposed downstream of the axial exhaust vane section (L1).

Abstract: A turbo-molecular pump has a casing, a stator fixedly mounted in the casing, and a rotor supported in the casing for rotation relatively to the stator. A turbine blade pumping assembly and a thread groove pumping assembly for discharging gas molecules are disposed between the stator and the rotor. The rotor comprises at least two components constituting the turbine blade pumping assembly and the thread groove pumping assembly. The components are separable from each other at a predetermined position, and joined to each other to form the rotor.

Abstract: A vacuum exhaust system comprising a vacuum chamber; means for introducing a gas into the vacuum chamber; a main pump for exhausting the vacuum chamber and reducing a pressure of the vacuum chamber to a desired pressure; an auxiliary pump disposed downstream from the main pump; and piping for connecting them, wherein an outer diameter of connecting piping as a connection between the main pump and the auxiliary pump is ½ inch (12.7 mm) or less; and a length of the connecting piping and capability of the auxiliary pump are combined so that a back pressure of the main pump becomes 5 Torr or more. This vacuum exhaust system can realize cost reduction through a saving in entire space, simplification of piping construction work, and so on.

Abstract: A turbo-molecular pump of high safety and reliability has been developed so that if an abnormal condition should develop on the rotor structure, it will not lead to damage to the stator or pump casing to cause loss of vacuum in a vacuum processing system. The turbo-molecular pump comprises a pump casing housing a stator and a rotor therein, a vane pumping section and/or a groove pumping section comprised by the stator and the rotor, and a constriction releasing structure for releasing constriction of at least a part of the stator when an abnormal torque is applied to the stator by the rotor.

Abstract: A turbo-molecular pump has a casing, a stator fixedly mounted in the casing, and a rotor supported in the casing for rotation relatively to the stator. A turbine blade pumping assembly and a thread groove pumping assembly for discharging gas molecules are disposed between the stator and the rotor. The rotor comprises at least two components constituting the turbine blade pumping assembly and the thread groove pumping assembly. The components are separable from each other at a predetermined position, and joined to each other to form the rotor.

Abstract: A tire air pressure detecting apparatus has an tire air pressure detecting mechanism for detecting the air pressure of a tire of a motorcycle, and a second control mechanism for comparing an actual air pressure detected by the tire air pressure detecting mechanism with a stored air pressure threshold, and controlling an engine output when the actual air pressure becomes lower than said air pressure threshold. Since the air pressure detecting apparatus comprises a small number of constituent elements including the tire air pressure detecting mechanism and the second control mechanism for reducing an engine output under certain conditions, the tire air pressure detecting apparatus can easily be reduced in size and cost.

Abstract: A turbo-molecular pump evacuates gas with a rotor that rotates at a high speed. The turbo-molecular pump comprises a casing, a stator fixedly mounted in the casing and having stator blades, a rotor rotatably provided in the casing and having rotor blades alternating with the stator blades, and a radial turbine blade pumping section having a spiral ridge-groove section provided on at least one of surfaces, facing each other, of the stator blade and the rotor blade. At least one of the stator blade and the rotor blade which are located at a first stage of the radial turbine blade pumping section has such a shape that at least one of the stator blade and the rotor blade is smaller in thickness in a direction of gas flow.

Abstract: A turbo-molecular pump of high safety and reliability has been developed so that if an abnormal condition should develop on the rotor structure, it will not lead to damage to the stator or pump casing to cause loss of vacuum in a vacuum processing system. The turbo-molecular pump comprises a pump casing housing a stator and a rotor therein, a vane pumping section and/or a groove pumping section comprised by the stator and the rotor, and a constriction releasing structure for releasing constriction of at least a part of the stator when an abnormal torque is applied to the stator by the rotor.

Abstract: Between digital data signals, which are expressed using a notation system of three digit symmetric binary numbers (named “HEN2”), and analog signals, at least one way, mutual, or other conversions are made. Three digit symmetric binary numbers (HEN2), are a combination of signals in which at least one of two adjacent digits, at any digit position of one or more digits of 2-based three digit redundant binary numbers with one signal of three digits {n, o, p} expressing a value {−1, 0, 1} as a one-digit signal, is a signal “o” expressing zero. Thus three digits {−1, 0, 1} are used instead of the two digit {0, 1} binary system used in conventional A/D or D/A converters.

Abstract: A turbo-molecular pump of high safety and reliability has been developed so that if an abnormal condition should develop on the rotor structure, it will not lead to damage to the stator or pump casing to cause loss of vacuum in a vacuum processing system. The turbo-molecular pump comprises a pump casing housing a stator and a rotor therein, a vane pumping section and/or a groove pumping section comprised by the stator and the rotor, and a constriction releasing structure for releasing constriction of at least a part of the stator when an abnormal torque is applied to the stator by the rotor.

Abstract: HEN2, which is a combination of signals in which at least one of two adjacent digits at any digit position of one or more digits of a 2-based three digit redundant binary number with one signal of three digits {n, o, p} each expressing value {−1, 0, 1} as a one-digit signal is a signal “o” expressing zero, is handled as one set of notation, not as a subset of the three digit redundant binary number.

Abstract: Extendable bit teeth are supported by the guide grooves formed on the end face at the point of a bit body in such a manner as to be slidable. The extendable bit teeth slide along the guide grooves in an excavating direction to thereby project from the end face at the point of the bit body. The extendable bit teeth slide in an opposite direction to the excavating direction to project from the outer periphery of the point of the bit body. Since the extendable bit teeth are pressed against the ground during excavation, the extendable bit teeth projects from the outer periphery of the point of the bit body so that the bit gauge can be extended, and most of the excavation hole is excavated by the bit body.

Abstract: A central processing unit and a digital data processing system for performing arithmetic processing of numbers that are not presented using traditional 10 radix signed digits 0, 1, 2 . . . 9. The central processing unit and digital data processing system of this invention are configured to process numbers that are from a set of digits {X.sub.1, X.sub.2 . . . X.sub.2n+1 } wherein each of these digits represents a number between -n, . . . -1, 0, 1, . . . n such that n is an integer and n.gtoreq.1. Thus, for any number that comprises more than one digit the most significant digit represents both magnitude and positive/negative state of the number and the remaining least significant digits each have a radix of (2n+1).

Abstract: An ink jet printing apparatus has a casing which is divided into upper and lower regions by a dividing wall. In the lower region, between the dividing wall and the base of the casing is an ink circulation unit. A pump of the of the ink circulation unit passes ink from a main ink container to a tube and hence to a printing head of the apparatus. The ink circulation unit may have a filter for filtering the ink before it passes to the printing head, and also have a secondary ink container and a solvent container for containing ink and solvent which are passed to the main container as they are used up during printing. Access to the containers and the filter, which need periodic replacement, is via an access cover in the casing. The access cover is at the front of the casing so that it can be used by an operator when the printing apparatus is in its normal position. Above the dividing wall is a circuit board unit which controls the ink circulation unit, and also the printing head.

Abstract: A method of fusion splicing optical fibers. Cores of the optical fibers to be fusion spliced are arranged in such a manner that the ends of the corresponding cores of optical fibers opposingly face to each other between discharge electrodes for fusion splicing. Discharge current flowing between the discharge electrodes is automatically adjusted according to a number of the cores of the optical fibers to substantially provide an optimal correction to the discharge current in relation to the number of the cores of the optical fibers. The discharge current is further adjusted to a variation in atmospheric pressure to substantially provide an optimal correction to the discharge current in relation to the variation in atmospheric pressure.

Abstract: The invented auto-ranging device has a signal measuring A/D converter, a range-switching A/D converter of a faster processing speed, a range-switching amplifier with variable amplification capabilities, and a processing controller which utilizes the variable amplification factors to alter the output signals from the switching A/D converter to generate signals appropriate for a scale range of a multi-range measuring A/D converter.

Abstract: An air-pressure impact type drilling method and an apparatus for the same in which a piston of an air hammer drill is moved up and down by pressure air to produce impact energy and the impact energy of the piston is used to give impact vibrations repetitively to a drill bit. In the air-pressure impact type drilling method and the apparatus for the same, the air hammer drill is operated by the pressure air to be supplied from the ground, the air that has already been used for operation of the air hammer drill is exhausted onto the ground through an air exhaust pipe provided in a drilling pipe and communicating with an air exhaust passage formed in the air hammer drill, and substances cut out by the air hammer drill together with muddy water within the trench are discharged by means of a reverse circulation system while drilling on through the earth.