Abstract: Provided are a dual-frequency power-supply apparatus, a high-frequency heating apparatus, and a high-frequency quenching apparatus having a high durability. A dual-frequency power-supply apparatus 1 includes a power supply 10 that alternately outputs a low-frequency current and a high-frequency current. The power supply 10 has an inverter 30 that converts a direct current into the low-frequency current and the high-frequency current and a controller 40 that controls the inverter 30. The controller 40 repeats, in this order, a first output period T11 in which the low-frequency current is output, a first intermission T12 in which output is stopped, a second output period T13 in which the high-frequency current is output, and a second intermission T14 in which output is stopped.

Abstract: This breather device separates engine oil included in a blow-by gas. The breather device comprises a first route, an acceleration route, a branching route, and turn-back routes. The blow-by gas flows to the first route. The acceleration route is connected to a downstream side of the first route, and has a flow channel cross-sectional area smaller than that of the first route. The branching route is connected to a downstream side of the acceleration route, configured including a wall part orthogonal to the acceleration route, and branched into two routes by the wall part. The turn-back routes are connected to one route branching at the branching route, and are turned back so as to be parallel to the acceleration route and to head in the opposite direction from a progressing direction.

Abstract: An induction heating system includes induction heating apparatuses, each including a high-frequency current transformer, a low-frequency current transformer and a heating coil, a high-frequency input switch connected to the high-frequency current transformer, a low-frequency input switch connected to the low-frequency current transformer, a first power source to output a high-frequency electric power and a low frequency electric power, a second power source, a first power source output switch connectable to the first power source, a second power source output switch connectable to the second power source, and a switch controller. Each induction heating apparatus includes a heater controller to send a signal to the switching controller to turn on one of the first power source output switch and the second power source output switch, to turn off the other, and to switch on or off each of the high-frequency input switch and the low-frequency input switch.

Abstract: This breather device separates engine oil included in a blow-by gas. The breather device comprises a first route, an acceleration route, a branching route, and turn-back routes. The blow-by gas flows to the first route. The acceleration route is connected to a downstream side of the first route, and has a flow channel cross-sectional area smaller than that of the first route. The branching route is connected to a downstream side of the acceleration route , configured including a wall part orthogonal to the acceleration route, and branched into two routes by the wall part. The turn-back routes are connected to one route branching at the branching route, and are turned back so as to be parallel to the acceleration route and to head in the opposite direction from a progressing direction.

Abstract: An induction heating power supply apparatus includes a smoothing section to smooth pulsating current of DC power output from a DC power supply section, and an inverter to convert the DC power smoothed by the smoothing section to AC power. The smoothing section includes a pair of bus bars connected to the inverter and a capacitor connected to the pair of bus bars. Each of the bus bars has an external surface extending in a current flow direction, the external surface including a flat face having a larger surface dimension than another face of the external surface in a direction perpendicular to the current flow direction. The bus bars are arranged in a layered manner such that the flat faces of the bus bars are opposed to each other and such that an insulator is sandwiched between the flat faces of the bus bars.

Abstract: An engine device having gas injectors attached to an intake manifold fixed to a side surface of a cylinder head. A fuel gas injected from the gas injectors is premixed in the intake manifold, and the resulting gas is supplied to a plurality of cylinders and ignited by ignition devices. The intake manifold has a configuration in which a plurality of intake branch pipes communicating with the cylinders are branched from an intake collecting pipe at an air supply side. The intake branch pipes include bent portions. In the bent portions of the intake branch pipes, inside inner walls near the cylinder head are bent at an acute angle.

Abstract: An induction heating power supply apparatus includes a smoothing section to smooth DC power and an inverter section to convert the smoothed DC power into AC power. The inverter section has first and second modules, each having serially connected switching devices. Output bus bars are interposed between the first and second modules. The smoothing section has first bus bars connected to a DC power supply section and the first module, a capacitor connected to the first bus bars, second bus bars connected to the DC power supply section and the second module, and another capacitor connected to the second bus bars. The first and second bus bars extend parallel to the output bus bars. The first module is interposed between the first bus bars and the output bus bars. The second module is interposed between the second bus bars and the output bus bars.

Abstract: A power supply apparatus for induction heating is provided. The power supply apparatus includes a smoothing filter configured to smooth a pulsating current of DC power output from a DC power supply, and an inverter configured to convert the DC power that has been smoothed by the smoothing filter into AC power. The smoothing filter includes a plurality of capacitors having different internal inductances and connected to each other in parallel between input terminals of the inverter, each of the capacitors being connected to the input terminals of the inverter directly or through a pair of bus bars. The plurality of capacitors includes a first capacitor and a second capacitor, the first capacitor having smaller internal inductance than the second capacitor and a shorter conductive path between the input terminals of the inverter than the second capacitor.

Abstract: An engine device including an engine and a carburetor that vaporizes a liquefied fuel gas from a fuel gas source for storing a liquefied fuel gas, in which a part of coolant in the engine is distributed to the carburetor. The engine device further includes a water-cooled exhaust manifold having a coolant passage for cooling an exhaust gas passage and a path switching mechanism for connecting a coolant inlet of the carburetor to a carburetor coolant outlet of the engine or to a coolant outlet of the water-cooled exhaust manifold.

Abstract: An engine device having gas injectors attached to an intake manifold fixed to a side surface of a cylinder head. A fuel gas injected from the gas injectors is premixed in the intake manifold, and the resulting gas is supplied to a plurality of cylinders and ignited by ignition devices. The intake manifold has a configuration in which a plurality of intake branch pipes communicating with the cylinders are branched from an intake collecting pipe at an air supply side. The intake branch pipes include bent portions. In the bent portions of the intake branch pipes, inside inner walls near the cylinder head are bent at an acute angle.

Abstract: A power semiconductor module, a snubber circuit for the power semiconductor module, and induction heating power supply apparatus having the power semiconductor module are provided. The power semiconductor module includes a power semiconductor device configured to perform a switching operation, a casing inside which the power semiconductor device is provided, a control circuit board provided on top of an upper surface of the casing, a control terminal for the power semiconductor device being provided on the upper surface of the casing and connected to the control circuit board, and a shield plate disposed between the control circuit board and the upper surface of the casing to cover the upper surface of the casing and to cover at least one side surface of the casing.

Abstract: A power conversion apparatus and a power conversion method are provided for heat treatment. The power conversion apparatus includes a rectifier configured to convert AC power to DC power, a smoothing filter configured to control the DC power received from the rectifier to be constant, an inverter configured to convert the DC power received from the smoothing filer into high-frequency power by turning the DC power on and off using a switching device made of an SiC semiconductor, and a control unit configured to control the rectifier and the inverter. A rating of output power output from the inverter is determined in accordance with a frequency of the high-frequency power output from the inverter, a current-applying time, and an operation rate obtained by dividing the current-applying time by a sum of the current-applying time and a non-current-applying time.

Abstract: An induction heating system includes induction heating apparatuses, each including a high-frequency current transformer, a low-frequency current transformer and a heating coil, a high-frequency input switch connected to the high-frequency current transformer, a low-frequency input switch connected to the low-frequency current transformer, a first power source to output a high-frequency electric power and a low frequency electric power, a second power source, a first power source output switch connectable to the first power source, a second power source output switch connectable to the second power source, and a switch controller. Each induction heating apparatus includes a heater controller to send a signal to the switching controller to turn on one of the first power source output switch and the second power source output switch, to turn off the other, and to switch on or off each of the high-frequency input switch and the low-frequency input switch.

Abstract: An induction heating power supply apparatus includes a smoothing section to smooth pulsating current of DC power output from a DC power supply section, and an inverter to convert the DC power smoothed by the smoothing section to AC power. The smoothing section includes a pair of bus bars connected to the inverter and a capacitor connected to the pair of bus bars. Each of the bus bars has an external surface extending in a current flow direction, the external surface including a flat face having a larger surface dimension than another face of the external surface in a direction perpendicular to the current flow direction. The bus bars are arranged in a layered manner such that the flat faces of the bus bars are opposed to each other and such that an insulator is sandwiched between the flat faces of the bus bars.

Abstract: An induction heating, power supply apparatus includes a smoothing section to smooth DC power and an inverter section to convert the smoothed DC power into AC power, The inverter section has first and second modules, each having serially connected switching devices. Output bus bars are interposed between the first and second modules. The smoothing section has first bus bars connected to a DC power supply section and the first module, a capacitor connected to the first bus bars, second bus bars connected to the DC power supply section and the second module, and another capacitor connected to the second bus bars. The first and second bus bars extend parallel to the output bus bars. The first module is interposed between the first bus bars and the output bus bars. The second module is interposed between the second bus bars and the output bus bars.

Abstract: An induction heating system includes induction heating apparatuses, each including a high-frequency current transformer, a low-frequency current transformer and a heating coil, a high-frequency input switch connected to the high-frequency current transformer, a low-frequency input switch connected to the low-frequency current transformer, a first power source to output a high-frequency electric power and a low frequency electric power, a second power source, a first power source output switch connectable to the first power source, a second power source output switch connectable to the second power source, and a switch controller. Each induction heating apparatus includes a heater controller to send a signal to the switching controller to turn on one of the first power source output switch and the second power source output switch, to turn off the other, and to switch on or off each of the high-frequency input switch and the low-frequency input switch.

Abstract: A power conversion apparatus and a power conversion method are provided for heat treatment. The power conversion apparatus includes a rectifier configured to convert AC power to DC power, a smoothing filter configured to control the DC power received from the rectifier to be constant, an inverter configured to covert the DC power received from the smoothing filer into high-frequency power by turning the DC power on and off using a switching device made of an SiC semiconductor, and a control unit configured to control the rectifier and the inverter. A rating of output power output from the inverter is determined in accordance with a frequency of the high-frequency power output from the inverter, a current-applying time, and an operation rate obtained by dividing the current-applying time by a sum of the current-applying time and a non-current-applying time.

Abstract: A power supply apparatus for induction heating is provided. The power supply apparatus includes a smoothing filter configured to smooth a pulsating current of DC power output from a DC power supply, and an inverter configured to convert the DC power that has been smoothed by the smoothing filter into AC power. The smoothing filter includes a plurality of capacitors having different internal inductances and connected to each other in parallel between input terminals of the inverter, each of the capacitors being connected to the input terminals of the inverter directly or through a pair of bus bars. The plurality of capacitors includes a first capacitor and a second capacitor, the first capacitor having smaller internal inductance than the second capacitor and a shorter conductive path between the input terminals of the inverter than the second capacitor.

Abstract: An induction heating system includes induction heating apparatuses, each including a high-frequency current transformer, a low-frequency current transformer and a heating coil, a high-frequency input switch connected to the high-frequency current transformer, a low-frequency input switch connected to the low-frequency current transformer, a first power source to output a high-frequency electric power and a low frequency electric power, a second power source, a first power source output switch connectable to the first power source, a second power source output switch connectable to the second power source, and a switch controller. Each induction heating apparatus includes a heater controller to send a signal to the switching controller to turn on one of the first power source output switch and the second power source output switch, to turn off the other, and to switch on or off each of the high-frequency input switch and the low-frequency input switch.

Abstract: A low cost, compact, high performance flow sensor that can be made small in size even for use in a large flow rate and a mass flow controller using the same are provided. The flow sensor includes a bypass passage, a sensor passage, and a bridge circuit including heat-generating resistance wires that constitute a part of the bridge circuit and are wound around the sensor passage. The flow sensor determines a total flow rate of a fluid that flows in a branched manner through the bypass passage and the sensor passage at a predetermined flow ratio. The total flow rate is determined by detecting, as an unbalance of the bridge circuit, heat transfer caused by the fluid flowing through the sensor passage and is outputted as a sensor output of the flow sensor. In the flow sensor, the bypass passage includes a plurality of fine flow passages each having a cross-section defined by a substantially linear edge and a curve in contact with the substantially linear edge.