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Hitachi Industrial Equipment Systems Co., Ltd.

Hitachi Industrial Equipment Systems Co., Ltd. Patent applications
Patent application numberTitlePublished
20120119685POWER TRANSDUCER - The performance of a power transducer is improved while efficiently using a power semiconductor also by managing the permissible duty factor of the power semiconductor in the regenerative braking circuit provided in the power transducer. The user is allowed to set, through an operation panel provided on the power transducer, the resistance value of the regenerative braking resistor for thermally consuming the rotational energy generated during motor deceleration. The power transducer performs the steps of: calculating the current which flows in the regenerative braking circuit from the resistance value setting; obtaining the generation loss of the power semiconductor in the regenerative braking circuit with the calculated current value; and determining the permissible duty factor of the power semiconductor from the obtained generation loss.05-17-2012
20120119505Transformer for Wind Power Station and/or Wind Power Generating Facilities Installed with Transformer for Wind Power Station - The transformer comprises a transformer body and natural convection cooling type radiators for release of heat of the transformer body. The transformer body is accommodated in a wind power generating facility, and air outside the wind power generating facility comes into contact with the natural convection cooling type radiators to cool the same.05-17-2012
20120009077Scroll Fluid Machine - A scroll fluid machine with ensured reliability of an oil seal and a bearing even in a compressor operation at high rpm and high load is provided, which includes: a fixed scroll; an orbiting scroll facing the fixed scroll and having a boss provided on a face opposite to the fixed scroll; a drive shaft having a leading end mounted to the boss; an orbiting bearing supporting the drive shaft in connection with the orbiting scroll; and a seal member placed between the boss and the drive shaft to seal against a lubricant supplied to the orbiting bearing. The seal member has an oil lip producing action of moving the lubricant toward the orbiting bearing by rotation of the drive shaft. A communication passage is provided in the oil lip for communication between a space between the orbiting bearing and the seal member and a space outside the boss.01-12-2012
20110274574Water Injected Scroll Air Compressor - As pressure in a water tank rapidly rises when water inside a compressor is evaporated by the high temperature of compressed air and this situation makes the operation unstable, an object of the present subject matter is to address this problem. A water injected scroll air compressor is provided with: an air end of the scroll air compressor; a driving unit that generates driving force for the air end; a compressing path from a suction port to a discharge port; a portion to inject water into the compressing path; a discharge piping of air discharged from the air end; a tank provided on a path of the discharge piping for storing water separated from the compressed air; and a cooler that is provided on the path of the discharge piping between the tank and the air end and cools the compressed air discharged from the air end.11-10-2011
20110256001Reciprocating Compressor - A reciprocating compressor provided with a piston, which is compact and having high sealing performance is provided. A reciprocating compressor includes: a low-pressure compressor unit having a low-pressure piston and a low-pressure cylinder for compressing air with the low-pressure piston reciprocating while oscillating within the low-pressure cylinder; a high-pressure compressor unit having a high-pressure piston and a high-pressure cylinder for further compressing the air compressed in the low-pressure compressor unit with the high-pressure piston reciprocating while oscillating within the high-pressure cylinder; and a motor for driving the low-pressure compressor unit and the high-pressure compressor unit. A maximum tilt angle during oscillation of the low-pressure piston is made larger than a maximum tilt angle during oscillation of the high-pressure piston.10-20-2011
20110247486Reciprocating Compressor - A reciprocating compressor including an oscillation-type piston mechanism is provided with a piston ring which is mounted in a piston ring groove to seal space between a piston and a cylinder. A ring groove other than the piston ring groove is provided at an outer periphery of the piston on a side away from the piston ring groove and closer to a crank shaft. A guide ring, which is inhibited from radial movement and shaped like a skirt opened toward the crank shaft, is mounted in the ring groove.10-13-2011
20110210692Squirrel Cage Induction Motor and Squirrel Cage Induction Motor Driving System - A squirrel cage induction motor includes: a stator core (09-01-2011
20110194963Water Injected Scroll Air Compressor - A high reliability water injected scroll air compressor is provided. In the scroll air compressor provided with: an orbiting scroll; a fixed scroll corresponding the orbiting scroll; a motor that generates driving force for making the orbiting scroll orbit the fixed scroll; a compressing path from a suction port to a discharge port; and a portion for injecting water into the compressing path, the operation is controlled by switching operation in which water is injected into the compressing path and operation in which no water is injected. Corrosion, the failure of activation and a touch to the wrap respectively worried when water is injected into an air end are avoided by switching the operation with water injection and the operation without water injection as described above so as to prevent water from remaining in the air end.08-11-2011
20110181222MOTOR CONTROL SYSTEM AND METHOD - A highly efficient and reliable motor control system and motor control method are provided. The motor control system includes a motor having a plurality of sets of armature windings, a plurality of inverters which drive the plurality of sets of armature windings, and a plurality of control devices which control the inverters individually. In the motor control system: while a motor torque command is in a smallest-magnitude range, a first inverter is operated to energize a first set of armature windings; when the motor torque command increases into a next larger-magnitude range, the first and a second inverter are operated to energize the first and a second set of armature windings; when the motor torque command increases into a still next larger-magnitude range, the first, the second, and a third inverter are operated to energize the first, the second, and a third set of armature windings; and when the motor torque command increases into a largest-magnitude range, all inverters are operated to energize all sets of armature windings. Thus, the number of inverters driven and/or the number of sets of armature windings energized are sequentially changed according to the torque command.07-28-2011
20100315473Filter and Ink-Jet Recording Apparatus Having the Same - A filter, the alignment of which does not need to be adjusted, and an ink-jet recording apparatus having such a filter are provided, the ink-jet recording apparatus capable of avoiding leakage of residual liquids in filter exchange operation. The filter of the present invention includes an upper capsule member, a lower capsule member, and a filter medium. The upper capsule member has a central connecting port and a peripheral connecting port, and also has a pipe section that extends, within the capsule, from the peripheral connecting port to the vicinity of the bottom surface (the deepest section) of the lower capsule member. A liquid supplied from the peripheral connecting port via the pipe section is filtered through the filter medium, and the filtered liquid is output from the central connecting port.12-16-2010
20100303658Water-Cooled Oil-Free Air Compressor - A water-cooled oil-free air compressor which features compactness and ensures improved productivity and maintainability. The compressor is an oil-free screw compressor which includes a low pressure stage compressor body, an intercooler for water-cooling the compressed air discharged from the low pressure stage compressor body, a high pressure stage compressor body for further compressing the compressed air cooled by the intercooler, and an aftercooler for water-cooling the air discharged from the high pressure stage compressor body. The intercooler and aftercooler each have a plurality of units, all of which are almost equal in shape. A cooler header on each or either of the inlet and outlet sides for compressed air is shared by the units of each cooler.12-02-2010
20100303645Reciprocative Compressor - This invention provides a swing-type reciprocative compressor capable of maintaining long durability and preventing propagation of heat to the large end portion of a piston, even under high-compression.12-02-2010
20100233004Air Compressor of Water Injection Type - In a water injection air compressor including a compressor main body for compressing air, a water-feed line for feeding water to an actuation chamber in the compressor main body, an air release valve for releasing the compressed air from the compressor main body, and a control panel for executing an on-load operation mode in which water is fed into the actuation chamber and an air release valve is closed and a no-load operation mode in which the water is fed into the actuation chamber and the air release valve is opened, wherein the control panel further executes a dry operation mode in which the water is prevented from being fed into the actuation chamber and with the air release valve is opened.09-16-2010
20100232980Air Compressor - An air compressor 09-16-2010
20100221134SCROLL FLUID MACHINE - In a scroll air compressor as a scroll fluid machine capable of being downsized with an increased cooling effect, cooling air entering through a fixed inlet of a fixed cooling passage provided at the rear of a fixed scroll, and an orbiting inlet of an orbiting cooling passage provided at the rear of an orbiting scroll, is allowed to flow out of an fixed outlet and an orbiting outlet, respectively. Thereafter, the cooling air is guided to an outer periphery of the other end of the casing through a side duct and a guide duct, and then sucked into an inner peripheral side of a centrifugal fan to be discharged outwardly from an exhaust port provided in a fan cover.09-02-2010
20100192788MOTOR DRIVE CONTROL DEVICE - A motor drive control device including a power supply converter that is connected to an alternating-current power supply, a voltage detector that detects a direct-current voltage of the power supply converter, an inverter that is connected to a motor, and an energy storage device that is connected to a direct-current bus that connects the power supply converter and the inverter. The motor drive control device includes: a power-running operation start voltage setting section that sets a power-running operation start voltage of the power supply converter; a power-running operation start control section that causes the power supply converter to start a power-running operation when the direct-current voltage of the power supply converter has reached the power-running operation start voltage set by the power-running operation start voltage setting section; a power-running operation stop voltage setting section that sets a power-running operation stop voltage of the power supply converter; and a power-running operation stop control section that causes the power supply converter to stop the power-running operation when the direct-current voltage of the power supply converter has reached the power-running operation stop voltage set by the power-running operation stop voltage setting section.08-05-2010
20100166589SCROLL TYPE FLUID MACHINE - The invention reduces a centrifugal force of a orbiting scroll which acts on an auxiliary crank mechanism. A crank pin which is eccentric from a main shaft portion is formed in a drive shaft, and a main balance weight is provided in a base end side of the crank pin. The main shaft portion of the drive shaft is rotatably supported by using a main bearing, and the crank pin is attached to a orbiting bearing which is provided in a back face side of a orbiting scroll. Further, an internal gap of the main bearing is set to a value which is larger than a value obtained by subtracting the double value of an eccentric amount difference between an eccentric amount of an auxiliary crank shaft and an eccentric amount of the drive shaft from an internal gap of the orbiting bearing. Accordingly, the internal gap of the main bearing does not come to 0 even if a compressor comes to a steady state.07-01-2010
20100135840SCREW COMPRESSOR - A screw compressor comprising: a pair of male and female screw rotors; and an air-cooled heat exchanger, wherein the air-cooled heat exchanger is provided above a motor for driving the compressor body; wherein, with respect to a cooling wind for the air-cooled heat exchanger, the air-cooled heat exchanger is inclined to the upstream side; wherein the uppermost portion of a unit suction port for the air-cooled heat exchanger cooling winds is positioned below the uppermost portion of the air-cooled heat exchanger positioned at the uppermost portion; wherein the lowermost portion of the unit suction port for the air-cooled heat exchanger cooling wind is positioned below the lowermost portion of the air-cooled heat exchanger positioned at the lowermost portion; and wherein the cooling wind for the air-cooled heat exchanger is exhausted from a ceiling portion of the compressor unit. With this structure, it becomes possible to provide a compact screw compressor with less noise whose installation area can be reduced.06-03-2010
20100079956POWER TRANSDUCER - A power transducer is downsized by reducing the size of a power source board and highly reliable. The power source board is provided in the power transducer and for a large-current circuit. The power transducer includes a power semiconductor module having lead terminals. Of the lead terminals provided for the power semiconductor module and connected with the main circuit board, predetermined one or ones of the lead terminals is or are connected with the main circuit board in the vicinity of a main circuit terminal stage and at a position or positions lower than the main circuit terminal stage. Alternatively, predetermined one or ones of the lead terminals is or are connected with the main circuit board at a position or positions lower than a position at which the main circuit terminal stage is provided.04-01-2010
20100073411Ink Jet Recording Device - A conventional ink jet recording device has a phenomenon of such that a transverse pitch between longitudinal dot column of a first line and that of a second line of character lines to be printed becomes narrower than that between other longitudinal dot columns when printing out on a printing object traveling in high speed.03-25-2010
20100066790Image Display Apparatus - A configuration of an image display apparatus which can reduce a pump exclusive for solvent is provided.03-18-2010
20100028185Scroll Fluid Machine - A scroll fluid machine comprises a fixed-side member including a cylindrical casing and a fixed scroll fixed to the casing, and an orbiting scroll and a plurality of ball coupling devices provided between the fixed-side member and the orbiting scroll to prevent self-rotation of the orbiting scroll on its axis and receive a thrust load between the fixed-side member and the orbiting scroll. Each of the ball coupling devices comprises a first ball coupling mechanism for supporting the thrust load generated between the fixed-side member and the orbiting scroll and a second ball coupling mechanism disposed with a space from the first ball coupling mechanism to prevent the self-rotation of the orbiting scroll.02-04-2010
20100026770Ink Jet Recording Device - An ink jet recording device comprises a main body equipped with an ink container, an ink supply pump ink, an ink recovery pump, and a control unit. A printing head equipped with a nozzle emits ink supplied from the main body as ink particles. An electrification electrode electrifies the ink particles and a deflection electrode deflects the electrified ink particles. A gutter collects ink particles which are not used for printing. An exhaust circulation path connects the ink container and the gutter. The gutter comprises two members of an ink flow path block in which ink flows and an exhaust flow path block in which exhaust solvent vapor flows.02-04-2010
20100026754Ink Jet Recording Device - An ink jet recording device comprises a main body equipped with an ink container, an ink supply pump ink, an ink recovery pump, and a control unit. A printing head equipped with a nozzle emits ink supplied from the main body as ink particles. An electrification electrode electrifies the ink particles and a deflection electrode deflects the electrified ink particles. A gutter collects ink particles which are not used for printing. An exhaust circulation path connects the ink container and the gutter. The gutter comprises two members of an ink flow path block in which ink flows and an exhaust flow path block in which exhaust solvent vapor flows.02-04-2010
20090291012Production method for sintered part - A production method for a sintered part comprises preparing a metal powder and a binder composed of a thermoplastic resin and a wax, mixing the metal powder and 40 to 60 vol. % of the binder with respect to the metal powder into a mixed powder, and heating and kneading the mixed powder into a raw material. This production method further includes supplying a predetermined amount of the raw material in a hole of a die and compacting the raw material into a green compact having a predetermined shape by pressing the raw material by a punch. This production method further includes ejecting the green compact from the hole of the die, removing the binder from the ejected green compact by heating, and sintering the green compact by heating so as to diffusion bond particles of the green compact. The compacting is performed by pressing at a moving rate U of the punch, which is not more than a rate calculated from the following equation (1). In this case, ΔP (Pa) is pressing power of the punch, μ (Pa·s) is viscosity of the raw material, L (m) is a length of the green compact, and De (m) is a corresponding tube diameter.11-26-2009
20090189964Ink jet recording device - An ink jet recording device, comprises: a main body equipped with an ink container which accumulate ink, an ink supply pump which supplies the ink, an ink recovery pump which recovers the ink, and a control unit; a printing head equipped with a nozzle which jets the ink supplied from the main body as ink particles, an electrification electrode which electrifies the ink particles, a deflection electrode which deflects the electrified ink particles, and a gutter which collects ink particles which are not used for printing; and a cable in which an ink supply flow path for supplying the ink from the main body to the printing head, an ink recovery flow path for returning the ink particles collected by the gutter into the ink container, an exhaust circulation path which connects the ink container and the gutter, and various signal lines for connecting the control unit and the printing head, are arranged. The gutter comprises two members of an ink flow path block in which ink flows, and exhaust flow path block in which exhaust solvent vapor flows.07-30-2009
20090189960Inkjet recording apparatus - An inkjet recording apparatus includes a main body and a print head. The main body includes a mechanical portion and a control portion. The mechanical portion includes a pump that pressurizes or draws a liquid(s), such as an ink and/or a solvent, and a solenoid valve that switches between flow channels guiding the liquid to flow therethrough. The control portion controls respective operations including printing and running and stopping of the inkjet recording apparatus. The print head includes a nozzle that atomizes the ink pressure fed from the main body into ink droplets, a charging electrode that electrically charges the ink droplets, a deflecting electrode that forms an electric field that deflects the charged ink droplets, and a gutter that collects the ink unused for printing. The nozzle includes a surface-treated layer that repels the ink to a portion where the ink is supplied.07-30-2009
20090162254Recycle of Electrical Equipment - The present invention addresses a problem with conventional techniques for recycling electrical equipment that have a hardened epoxy resin and electroconductive material where a catalyst is degraded to an extent that it can no longer be reused when water is present in a dissolving system. Moisture, when present in the dissolving system for treating electrical equipment including electroconductive material of aluminum, may react with aluminum to produce an aluminate compound which is transformed into aluminum oxide (alumina) under heating, which, in turn, may cause abnormal temperature rise to melt aluminum. This may be accompanied by formation of hydrogen which can cause danger of explosion. The present invention manages moisture content in a dissolving system by drying an object to be treated with a catalyst and a solvent prior to the dissolving treatment.06-25-2009
20090146592POSITION SENSORLESS CONTROLLER FOR PERMANENT MAGNET MOTOR - In a calculation for estimating axis error in a permanent magnet motor, a d-axis commanded voltage value is added to the product of three signals, which are a q-axis detected current value or commanded current value, an inductance value, and an estimated speed value, and then the resulting value is divided by the product of a commanded speed value ω06-11-2009
20090136367Air compressor - Provided is an air compressor that can keep good alignment between pulleys 05-28-2009
20090058331Semiconductor Power Converter - A semiconductor power converter includes a power converter for converting direct current to three-phase alternating current or vice versa; a means for detecting a current in an alternating current side of the power converter; a means for providing a current reference in the alternating current side of the power converter; a current controller for calculating a voltage reference in the alternating current side of the power converter to match the current reference and a value of the detected current; and a pulse width modulation means for controlling the power converter through pulse width modulation based on the voltage reference, wherein the current reference is used in place of the value of the detected current for at least one phase current among three phase currents in the alternating current side.03-05-2009
20090040797Pulse Width Modulation Method for a Power Converter - A pulse width modulation method has the steps of operating a second instruction signal so that each of the differences between two or three arbitrary instruction signals in three first instruction signals may become more than the predetermined value, and modulating in pulse width based on the second instruction signal.02-12-2009
20090040283INKJET RECORDING APPARATUS - An inkjet recording apparatus comprises a main body, a print head, and a cable. The main body includes an ink container for storing ink, an ink supply pump for supplying the ink, and an operation control section. The print head includes a nozzle for expelling the ink supplied from the main body as ink particles, charging electrodes for charging the ink particles, deflecting electrodes for deflecting the charged ink particles, and a gutter for collecting ink particles that have not been used for printing. The cable includes an ink supply path through which the ink is supplied from the main body to the print head, an ink collecting path through which the ink particles collected in the gutter are returned to the ink container, signal lines interconnecting the operation control section and the print head. An ink collecting pump for transferring the ink particles collected in the gutter to the ink container is disposed in the print head.02-12-2009
20090040248INKJET RECORDING APPARATUS - An inkjet recording apparatus comprises a main body, a print head, and a cable. The main body includes an ink container for storing ink, an ink supply pump for supplying the ink, and an operation control section. The print head includes a nozzle for expelling the ink supplied from the main body as ink particles, charging electrodes for charging the ink particles, deflecting electrodes for deflecting the charged ink particles, and a gutter for collecting ink particles that have not been used for printing. The cable includes an ink supply path through which the ink is supplied from the main body to the print head, an ink collecting path through which the ink particles collected in the gutter are returned to the ink container, signal lines interconnecting the operation control section and the print head. An ink collecting pump for transferring the ink particles collected in the gutter to the ink container is disposed in the print head.02-12-2009
20090034309Electric power conversion system - In the present invention, miniaturization of an electric power conversion system is made possible while the reduction of a rise in temperature is achieved through a cooling operation by a cooling fan. The electric power conversion system is provided with a casing for covering cooling fins for cooling power semiconductors, a main circuit board having a driver circuit for driving the power semiconductors, and a cover for covering up the main circuit board. The system includes a first airflow hole provided at a part of the main circuit board, on the upper side of an air-intake provided in the cover, and a second airflow hole provided on the lower side of the first airflow hole, and on the lower side of the cooling fins, wherein air from the second airflow hole is driven to the cooling fins by a cooling fan.02-05-2009
20090018223Recycle of electrical equipment - The conventional techniques for recycling an electrical equipment including a hardened epoxy resin and electroconductive material has involved conventional problems that a catalyst is degraded to an extent that it can be no longer reused when a water is contained in a dissolving system.01-15-2009

Patent applications by Hitachi Industrial Equipment Systems Co., Ltd.