Abstract: A suspension arm includes a main body. The main body includes a curved portion curved along a longitudinal direction and has a closed section. The main body includes an inner side wall, an outer side wall, a first side wall, and a second side wall. The inner side wall corresponds to an inner side of a curve of the curved portion. The outer side wall corresponds to an outer side of the curve of the curved portion. A thickness of the inner side wall is larger than a thickness of the outer side wall. In sectional view of the main body perpendicular to the longitudinal direction, each of a length of the first side wall and a length of the second side wall is longer than each of a length of the inner side wall and a length of the outer side wall.

Abstract: Provided is a burring processing method, which is a method for forming a buffing processed portion including a raised portion and a curved portion in a metal component having a pilot hole formed therein, the method being characterized by including: a preforming step of enlarging a diameter of the pilot hole, moving an edge portion of the pilot hole relative to the metal component in a first direction of a thickness direction of the metal component in a first range around the pilot hole of the metal component, and forming the whole first range into a preformed portion raised from the metal component in the first direction; and a main forming step of deforming the preformed portion in a second direction opposite to the first direction, forming a second range on an outer diameter side of the preformed portion to have the same height as the first range in the first direction, and forming part of a third range on an inner diameter side of the preformed portion from the second range to be part of the curved portion

Abstract: In a power conversion device, a capacitor series circuit is connected in parallel with a direct current power supply, outputs an alternating current voltage having three or more potentials in a half-cycle period with the capacitor series circuit as a direct current input, wherein a neutral point of an alternating current load and an intermediate connection point of the capacitor series circuit are directly connected, the voltage of each of the capacitors is detected, and a zero voltage vector obtained by making each alternating current output of the same potential is adjusted in accordance with the difference between the voltages.

Abstract: A current detector includes a chopper circuit composed of a switching circuit, i.e. an inverse-parallel circuit composed of an insulated gate bipolar transistor IGBT and a diode, and a switching circuit, i.e. an inverse-parallel circuit composed of an IGBT and a diode, which are connected in series. When the diode on the opposite arm is turned on, a reverse recovery current is detected and its output is directed to a gate drive circuit via an insulating circuit. A switch in the gate drive circuit is opened to increase resistance, in order to reduce the speed at which the gate of the switching device is charged. Thus, the surge voltage and its increase ratio are reduced without reducing a switching speed or requiring a snubber circuit.

Abstract: A balancing circuit balances the steady-state currents of the switching devices in an electric power converter, which facilitates reducing the size of the power converter and precisely balancing the steady-state currents. The balancing circuit holds transient sensing voltages at the time of turning-on of the switching devices, and detects the unbalance between the currents of the switching devices based on the distribution or unbalance of the sensing voltages by comparing the steady-state sensing voltages or the values corresponding to the steady-state sensing voltages with the stored transient sensing voltages. The steady-state currents of the switching devices are balanced by regulating the drive voltages of the switching devices based on the detected distribution of the steady-state currents.