Abstract: A centrifugal blower comprises: an impeller (2) provided with blades (12); a casing (3) that houses the impeller (2), surrounds the impeller (2) on an outer side of the impeller (2) in a radial direction of the impeller (2) to form a spiral flow passage (C1) through which air (AR) can flow, and is provided with a nose section (30) forming a start point (S) of the spiral flow passage (C1) and an end point (E) of the spiral flow passage (C1) where one turn of the spiral flow passage (C1) from the start point (S) terminates; a drive unit (4) that rotates the impeller (2) about the center axis (O) of the impeller (2); and a vane (5) that is provided on the bottom plate (22) of the casing (3), divides the spiral flow passage (C1) in the radial direction of the impeller (2), and extends along a circumferential direction of the impeller (2). The rear edge (6) of the vane (5) is located upstream from the nose section (30) in a primary flow direction (DI) of the spiral flow passage (C1).

Abstract: A battery charger (1000) non-concurrently performing a first operation to charge a main battery (MBA) and a sub-battery (SBA) by using an external power supply (AC), and a second operation to charge the sub-battery by using the main battery, including: a power supply circuit (1); a transformer (3); a secondary-side circuit (4) rectifying a voltage induced in a winding (302) and supplying the voltage to the main battery in a first time period for the first operation, and converting a DC voltage from the main battery into an AC voltage and supplying the AC voltage to the winding in a second time period for the second operation; a conduction angle adjustment circuit (7); and a control circuit (10), the secondary-side circuit being a full-bridge circuit including parallel-connected arms each including parallel-connected bodies connected in series, the parallel-connected bodies each including a switching unit and a rectifying unit connected in parallel.

Abstract: Provided are a flat heat exchange tube, a heat carrier-heating device, and an air conditioner for a vehicle by which it is possible to reduce thermal contact resistance and improve thermal conductivity. A flat heat exchange tube is provided with: a flat tube constituted of a pair of molded plates; and wavy inner fins that are inserted between the molded plates, tips protruding in one direction and tips protruding in another direction of the wavy inner fins being soldered to the inner surfaces of the pair of molded plates. The wavy inner fins are provided with expansion allowance portions in a wall surface between the tips allowing deformation in a direction by which the distance between the tips increases, the flat heat exchange tube being expandable through the expansion allowance portion in a state in which the tips between the pair of molded plates are soldered thereto.

Abstract: The heat medium heating device includes: a casing in which the flat heat exchange tubes 12 and the PTC heater 13 are stacked in multiple layers and incorporated; and a control substrate of the PTC heater 13 incorporated in the casing. In the heat medium heating device in which a terminal 25A extending from each electrode plate 25 of the PTC heater 13 is directly connected to a connection portion of the control substrate, the width dimension of the flat heat exchange tubes 12 is greater than a contact surface width in a direction in which the terminal 25A extends from each electrode plate 25 in the PTC element 24 of the PTC heater 13, and the electrode plates 25 and the flat heat exchange tubes 12 excluding the PTC element 24 are superimposed in the wide portion.

Abstract: A heater control device includes a current calculating unit (20) which calculates a third value of current based on a first value of current flowing through a first PTC element of a first PTC heater which is in an energized state and a second value of current estimated to flow through a second PTC element of a second PTC heater which is to be newly put into an energized state next, and a switching control unit (21) which maintains a non-energized state of the second PTC element of the second PTC heater until it is determined that the third value of current calculated by the current calculating unit (20) is less than a predetermined maximum allowable value of current and puts the second PTC element of the second PTC heater into an energized state when the third value of current is less than the predetermined maximum allowable value of current.

Abstract: The heat medium heating device is provided with the following: a plurality of flat heat exchange tubes in which U-turn flow channels are formed; a heat medium inlet and outlet header to which heat medium inlet and outlet pipes are connected, and to which one end of each of the flat heat exchange tubes is connected at predetermined intervals and is jointed by brazing; and a plurality of sets of PTC heaters stacked between the flat heat exchange tubes. A heat exchange element comprising the flat heat exchange tubes, the heat medium inlet and outlet header, and the PTC heaters is sandwiched between a holding plate or a bottom face of a housing and a substrate mount, and is accommodated and installed within the housing in a state where the flat heat exchange tubes and the PTC heaters are in close contact.

Abstract: A heater control device having at least two PTC heaters having PTC elements includes switching units which are provided so as to correspond to the PTC heaters and which switch an energized state and a non-energized state of the PTC elements by being turned ON and OFF, pattern information which defines state combination patterns of the energized state and the non-energized state of the PTC elements with respect to a required power value for the heater unit, and a ratio controlling unit which when the required power for the heater unit is at an intermediate value of the required power values defined in the pattern information, controls a ratio of the energized state to the non-energized state of the PTC elements based on a ratio of ON time to OFF time for which an average power within a certain period matches the required power.

Abstract: Provided is a heat medium heating unit comprising a plurality of flat heat exchange tubes, PTC heaters incorporated between flat tube portions, a heat exchanger pressing member that presses from one side the flat tubes and the PTC heaters against the inner surface of a casing, and a control board that is disposed above the heat exchanger pressing member and that controls the PTC heaters. A terminal extending upwards from an electrode plate directly connects to a terminal supports of the control board. On an inner surface of the casing, since a positioning means that engages with the terminal to position the terminal and the plate, the thermal contact resistance between the flat heat exchanger tubes and the PTC heaters is reduced.

Abstract: The disclosure provides a heating medium heating apparatus by which it is possible to directly detect a temperature of a semiconductor switching element such as an IGBT, and to perform high-reliability overheating protection control, while suppressing the number of installations of the temperature sensor, and provides a vehicle air conditioner provided with the heating medium heating apparatus. In the heating medium heating apparatus, at least two PTC heaters are provided, the energization of the PTC heaters is respectively ON/OFF-controlled by a plurality of circuits, each containing a semiconductor switching element (34), and the amount of heating is adjusted. Overheating protection temperature sensors (58 and 59) are respectively installed between two pairs of adjacent semiconductor switching elements (34) of a plurality of the semiconductor switching elements (34).

Abstract: In a heat medium heating device 10 in which a heat exchange element 20 formed by stacking multiple flat heat exchange tubes 21 and multiple pairs of PTC heaters 26 in multiple layers is fastened and fixed into a casing 11 including heat medium outlet and inlet paths 15 and 16, connection portions 48 and 49 between a power supply HV harness and a control LV harness 44 are provided on an outer surface on one surface side where the heat medium outlet and inlet paths 15 and 16 of the casing 11 are provided, and a control substrate 33 that controls energization to the PTC heaters 26 is disposed on an inside on the same side as a surface on which the connection portions 48 and 49 of the casing 11 is provided.

Abstract: A power converter including: a transformer in which first and second voltages are induced; a full-bridge circuit including parallel-connected first and second arms each including series-connected FETs; and a control circuit, wherein, within a given time period for which a voltage V2 is the first voltage, the control circuit performs control so that FETs in at least one arm are on for an on time period, and, when Pon, PX, PS, ?, and ? respectively denote a duration of the on time period, a duration of the given time period, a duration of a time period from the end of the on time period to a time point of transition from the first to second voltage, a rise time of a body diode of each FET, and a fall time of the body diode, Pon>(?/?)PS, 0?PS<?, and Pon+PS?PX are satisfied.

Abstract: A battery charger (1000) non-concurrently performing a first operation to charge a main battery (MBA) and a sub-battery (SBA) by using an external power supply (AC), and a second operation to charge the sub-battery by using the main battery, including: a power supply circuit (1); a transformer (3); a secondary-side circuit (4) rectifying a voltage induced in a winding (302) and supplying the voltage to the main battery in a first time period for the first operation, and converting a DC voltage from the main battery into an AC voltage and supplying the AC voltage to the winding in a second time period for the second operation; a conduction angle adjustment circuit (7); and a control circuit (10), the secondary-side circuit being a full-bridge circuit including parallel-connected arms each including parallel-connected bodies connected in series, the parallel-connected bodies each including a switching unit and a rectifying unit connected in parallel.

Abstract: A power converter including: a transformer in which first and second voltages are induced; a full-bridge circuit including parallel-connected first and second arms each including series-connected FETs; and a control circuit, wherein, within a given time period for which a voltage V2 is the first voltage, the control circuit performs control so that FETs in at least one arm are on for an on time period, and, when Pon, PX, PS, ?, and ? respectively denote a duration of the on time period, a duration of the given time period, a duration of a time period from the end of the on time period to a time point of transition from the first to second voltage, a rise time of a body diode of each FET, and a fall time of the body diode, Pon>(?/?)PS, 0?PS<?, and Pon+PS?PX are satisfied.

Abstract: Provided are: a heat medium heating device capable of bringing: flat heat exchange tubes and PTC heaters; and inlet/outlet header parts of the flat heat exchange tubes, into sufficiently close contact with each other, and incorporating these components into a casing; and a vehicular air-conditioning device including the same. In a heat medium heating device, flat heat exchange tubes each including a flat tube part and inlet/outlet header parts and PTC heaters are stacked in layers, and a heat exchange holding member presses the flat heat exchange tubes from one side, whereby the stacked structure is incorporated on an inner bottom surface of a casing. In this configuration, at least uppermost one of the flat heat exchange tubes has one surface pressed by the heat exchange holding member, the one surface being formed into a planar shape in which the flat tube part and the inlet/outlet header parts are flattened.

Abstract: A heat medium heating device including flat heat exchange tubes and PTC heaters stacked in a plurality of layers, the heat medium heating device being capable of correctly and accurately detecting the temperature of a circulating heat medium; and a vehicular air-conditioning device including the same. In a heat medium heating device, flat heat exchange tubes each including an inlet header part and an outlet header part and PTC heaters are stacked in a plurality of layers, and are incorporated in a casing including a heat medium inlet path and a heat medium outlet path communicated with the inlet and outlet header parts. In the heat medium heating device thus configured, an inlet temperature sensor and an outlet temperature sensor that detect the temperature of a heat medium are provided around the inlet and outlet header parts of the lowermost flat heat exchange tube in the stacked structure.

Abstract: A heater control device having at least two PTC heaters having PTC elements includes switching units which are provided so as to correspond to the PTC heaters and which switch an energized state and a non-energized state of the PTC elements by being turned ON and OFF, pattern information which defines state combination patterns of the energized state and the non-energized state of the PTC elements with respect to a required power value for the heater unit, and a ratio controlling unit which when the required power for the heater unit is at an intermediate value of the required power values defined in the pattern information, controls a ratio of the energized state to the non-energized state of the PTC elements based on a ratio of ON time to OFF time for which an average power within a certain period matches the required power.

Abstract: A heater control device includes a current calculating unit (20) which calculates a third value of current based on a first value of current flowing through a first PTC element of a first PTC heater which is in an energized state and a second value of current estimated to flow through a second PTC element of a second PTC heater which is to be newly put into an energized state next, and a switching control unit (21) which maintains a non-energized state of the second PTC element of the second PTC heater until it is determined that the third value of current calculated by the current calculating unit (20) is less than a predetermined maximum allowable value of current and puts the second PTC element of the second PTC heater into an energized state when the third value of current is less than the predetermined maximum allowable value of current.

Abstract: Provided is a heat medium heating unit comprising a plurality of flat heat exchange tubes, PTC heaters incorporated between flat tube portions, a heat exchanger pressing member that presses from one side the flat tubes and the PTC heaters against the inner surface of a casing, and a control board that is disposed above the heat exchanger pressing member and that controls the PTC heaters. A terminal extending upwards from an electrode plate directly connects to a terminal supports of the control board. On an inner surface of the casing, since a positioning means that engages with the terminal to position the terminal and the plate, the thermal contact resistance between the flat heat exchanger tubes and the PTC heaters is reduced.

Abstract: Provided are a layered heat exchanger that can prevent deterioration of sealing property due to deformation of sealing portions of inlet and outlet header sections when a PTC heater is sandwiched between flat heat exchanger tubes, and is pressed to be brought into close contact with the flat heat exchanger tubes, and a heat medium heating apparatus and a vehicle air-conditioning apparatus using the layered heat exchanger.

Abstract: An object of the present invention is to provide a small, lightweight, and inexpensive heat medium heating apparatus in which a flat tube heat exchanger and a PTC heater are laminated in a multi-layered manner to reduce a thermal contact resistance thereamong, heat transfer performance is improved, and also in which assembling of the flat tube heat exchanger and the PTC heater is made easier.