Abstract: A method for manufacturing a rotor core includes detecting a height of a projecting portion formed on a lower die by a height detecting unit, and placing onto the lower die a core body in which a magnet insertion hole is formed such that the projecting portion is positioned in the magnet insertion hole when the height detecting unit has determined that the height of the projecting portion is within a set range. Additionally, the method includes bringing a permanent magnet in the magnet insertion hole into contact with an upper end of the projecting portion, and placing onto the core body a holding member after bringing the permanent magnet into contact with the upper end of the projecting portion. Melted resin is injected into the magnet insertion hole in which the permanent magnet has been inserted after placing the holding member onto the core body.

Abstract: In a method of manufacturing a laminated core, a laminated core body 14 including magnet insertion holes 12 and 13 with magnet pieces 15 inserted therein is placed between a molding (upper) die 10 and a retaining (lower) die 11, and a molding resin 19 is filled from resin reservoir portions (pots) 16 to fix the pieces 15 in the holes 12 and 13. Between the die 10 and the body 14, a guide member 18 is placed, which includes resin passages 31 provided from the portions 16 to the holes 12 and 13 and gates 30 connecting to the holes 12 and 13 on downstream sides of the passages 31. The method can reduce lead time of a production line without replacing the molding dies for different laminated rotor cores and thus without preparing different types of molding dies.

Abstract: In a method of manufacturing a laminated core, a laminated core body 14 including magnet insertion holes 12 and 13 with magnet pieces 15 inserted therein is placed between a molding (upper) die 10 and a retaining (lower) die 11, and a molding resin 19 is filled from resin reservoir portions (pots) 16 to fix the pieces 15 in the holes 12 and 13. Between the die 10 and the body 14, a guide member 18 is placed, which includes resin passages 31 provided from the portions 16 to the holes 12 and 13 and gates 30 connecting to the holes 12 and 13 on downstream sides of the passages 31. The method can reduce lead time of a production line without replacing the molding dies for different laminated rotor cores and thus without preparing different types of molding dies.

Abstract: A method of manufacturing a rotor core having a plurality of core members stacked together includes determining weight imbalances for the plurality of core members with respect to a central axis of the rotor core; combining the weight imbalances of the plurality of core members to determine a weight distribution of the rotor core; and displacing the weight imbalances of one or more of the plurality of core members to adjust a position of the weight distribution of the rotor core with respect to the central axis.

Abstract: A laminated core includes: a laminate in which 1st to Nth (N is a natural number of two or more) core members are laminated in this order; and a distinguishing mark formed with a marking that is placed on a peripheral surface of the laminate so as to be continuously positioned over all of the 1st to Nth core members.

Abstract: A method of manufacturing a laminated stator core includes: blanking an electrical steel sheet at 1st to Nth (N is a natural number equal to or greater than 2) positions arranged in a row in the width direction of the electrical steel sheet to form 1st to Nth blank members, and laminating the 1st to Nth blank members to form a laminated stator core. The shape or arrangement of at least one odd-shaped part of a plurality of odd-shaped parts in the kth (k is a natural number of 1 to N) blank member differs from the shape or arrangement of at least one odd-shaped part of a plurality of odd-shaped parts in the mth (m is a natural number of 1 to N and satisfying m?k) blank member such that the shapes of given two blank members do not agree with each other.

Abstract: There is provided a method for measuring a laminated iron core. The method includes preparing a laminated iron core in which two or more kinds of metal plates with different shapes are laminated and a deformed part is formed inside a hole continuing in a lamination direction of the laminated iron core, acquiring a surface profile data indicating a surface shape of the deformed part through an inlet of the hole by a non-contact sensor located in an outside of the hole, and calculating a size of the deformed part by a calculator based on the surface profile data.

Abstract: There is provided a method of manufacturing a laminated rotor core, including: a mounting step of placing a core body on a carrier tray, the core body having a plurality of magnet insertion holes provided around the shaft hole, the carrier tray having a mount plate and a columnar guide member standing on a front surface of the mount plate 41, the placement of the core body being carried out by fitting the guide member into the shaft hole; an inserting step of inserting permanent magnets respectively in the magnet insertion holes; an injecting step of injecting a liquefied resin material in each of the magnet insertion holes; and a first preheating step of heating the core body before the mounting step, wherein the inserting step and the injecting step are carried out in a state in which the core body is placed on the carrier tray.

Abstract: A method of resin sealing a permanent magnet in a magnet insertion portion of a laminated body, the body formed by laminating plural core sheets and including the plural portions formed around a shaft hole in a center of the plural portions, the portion connected to an internal space via an opening. The method includes a first process of positioning a blocking member blocking the opening from a side of the space in a way that the member is vertically-placed in a lower die or an upper die, while the both dies hold the body from both sides in an axial direction and close the portion; and a second process of filling a resin extruded from a resin reservoir portion provided in the die or the die into the portion having the magnet inserted and having the opening closed by the member.

Abstract: A method of manufacturing a laminated core, having a laminated core body 10a formed by laminating plural core sheets 11 and having magnet insertion holes 13, 14 with openings 17, 18 opening to a inner space 15 or an external side, inserting and resin-sealing permanent magnets 20, 21 in the magnet insertion holes 13, 14, with the openings 17, 18 blocked by a blocking member 23, the method including: temporarily connecting blocking member pieces 32 to be the blocking member 23 in each of the core sheets 11 and removing the blocking member 23 with the laminated core body 10a resin-sealed. By this, without a special blocking member, the permanent magnets 20, 21 are resin-sealed while the magnet insertion holes 13, 14, parts of which have the openings 17, 18, are blocked.

Abstract: In the case of a laminated rotor core 10, insertion of permanent magnets 14 and filling of resin 15 into each of magnet insertion holes 13 are performed in order to cancel out a problem of an imbalanced weight estimated from a deviation of lamination thickness in a circumferential direction of a laminated core body 12, and a manufacturing method includes a step of measuring a deviation of lamination thickness in which an imbalanced weight is estimated by measuring the deviation of lamination thickness in the circumferential direction of the laminated core body 12, and a step of balance adjustment in which the insertion of the permanent magnets 14 into each of the magnet insertion holes 13 and the filling of resin 15 into each of the magnet insertion holes 13 are performed in a manner that cancels out a problem of this imbalanced weight.

Abstract: A power supply circuit includes a bridge circuit, a transformer, and a rectifying and smoothing circuit. The bridge circuit includes at least one switching element and converts a direct-current voltage into an alternating-current voltage according to ON and OFF of the switching element. The transformer includes a primary winding wire and a secondary winding wire. The rectifying and smoothing circuit converts the alternating-current voltage into a direct-current output voltage and supplies the direct-current output voltage to a direct-current load. When the number of turns of the primary winding wire is represented as N1, the number of turns of the secondary winding wire is represented as N2, a voltage value of the direct-current voltage is represented as VDC, and a lower limit value of the output voltage is represented as Vmin, a turn ratio of the primary winding wire and the secondary winding wire is about N1:N2=(VDC/2):Vmin.

Abstract: According to one embodiment, there is provided a power supply device which includes a power conversion circuit which outputs an input power to an LED element as a load by converting the input power into a predetermined output power; and a control circuit which performs a feedback control of the power conversion circuit by detecting the output power of the power conversion circuit, and performs a dimming control which causes the LED element to be subject to a dimming operation based on a dimming signal which is output from a dimmer, in which, when a dimming OFF signal is input, the power conversion circuit outputs power which causes the LED element to be turned off while continuing an operation of the power conversion circuit.

Abstract: A power supply circuit includes a rectifying circuit, a power-factor improving circuit, a bridge circuit, a transformer, a rectifying and smoothing circuit, first and second drivers, a power supply section, and a control section. The rectifying circuit converts an alternating-current input voltage into a rectified voltage. The power-factor improving circuit improves a power factor of the rectified voltage and converts the rectified voltage into a direct-current voltage. The bridge circuit converts the direct-current voltage into an alternating-current voltage. The rectifying and smoothing circuit converts the alternating-current voltage into a direct-current output voltage. The first driver controls a switching element. The second driver controls the power-factor improving circuit. The power supply section converts the direct-current voltage into a driving voltage corresponding to the first and second drivers.

Abstract: According to one embodiment, there is provided a power supply circuit including a direct-current voltage source, a bridge circuit, a transformer, and a rectifying and smoothing circuit. The bridge circuit includes at least one switching element and converts a direct-current voltage supplied from the direct-current voltage source into an alternating-current voltage according to ON and OFF of the switching element. The transformer includes a primary winding wire connected to the bridge circuit and a secondary winding wire magnetically coupled to the primary winding wire. The rectifying and smoothing circuit converts the alternating-current voltage output from the secondary winding wire into a direct-current output voltage and supplies the direct-current output voltage to a direct-current load. The bridge circuit includes a capacitor connected between the primary winding wire and a terminal on a low potential side of the direct-current voltage source.

Abstract: A power supply circuit includes a bridge circuit, a transformer, a rectifying and smoothing circuit, a driver, a feedback circuit, and a power supply section. The bridge circuit converts a direct-current voltage into an alternating-current voltage. The transformer includes a primary winding wire and a secondary winding wire. The rectifying and smoothing circuit converts the alternating-current voltage into a direct-current output voltage and supplies the direct-current output voltage to a direct-current load. The driver controls ON and OFF of the switching element. The feedback circuit receives a detection signal of an output current flowing to the direct-current load and a differential signal obtained from fluctuation of the output voltage and feedback-controls the driver on the basis of the signals. The power supply section generates a driving voltage corresponding to the feedback circuit from the output voltage and supplies the driving voltage to the feedback circuit.

Abstract: According to one embodiment, a power supply device includes a terminal connected to an output of a dimmer, a rectifier circuit, a switching circuit including an inductor, a switching element connected to the inductor in series, and a first rectifying element and configured to change the switching element to an ON state to feed an output current of the rectifier circuit to the inductor, after the dimmer changes from a non-conduction state to a conduction state, when the dimmer is a dimmer of a phase control type, and configured to change the switching element to the ON state to feed the output current of the rectifier circuit to the inductor, after the dimmer changes from the non-conduction state to the conduction state, when the dimmer is a dimmer of an anti-phase control type, and a DC-DC converter configured to convert the output voltage of the switching circuit.

Abstract: According to one embodiment, a power supply device includes a rectifying circuit configured to rectify an alternating-current power supply, a first capacitor configured to smooth a voltage after rectification, and a falling voltage chopper circuit configured to supply electric power to a load. The first capacitor is set to a capacity in which a section where a voltage after smoothing drops to an output voltage to the load is provided in a rectified half period of the alternating-current power supply. The falling voltage chopper circuit includes at least one switching element configured to receive an input of the voltage after smoothing, operate in a section where the voltage after smoothing exceeds the output voltage, and pause in a section of the output voltage and a second capacitor provided on an output side and having a capacity larger than the capacity of the first capacitor.

Abstract: There is provided a rotor core which increases the quality and reliability thereof by preventing the occurrence of a core separation of the rotor core. There is provided a rotor core including a plurality of substantially cylindrical core blocks which are stacked on each other; and a plurality of magnets, characterized in that a plurality of magnet holes extending in an axial direction are provided in the plurality of core blocks so as to extend over the plurality of core blocks in that the plurality of magnets are accommodated in each of the plurality of magnet accommodation holes and fixed therein with a resin, and in that an axial position of core block boundary planes where the plurality of core blocks are brought into abutment with each other and an axial position of magnet boundary planes where the plurality of magnets are brought into abutment with each other differ from each other.

Abstract: According to one embodiment, provided is a power supply circuit including a power conversion unit, a controller, and an integrated circuit. The power conversion unit converts an AC voltage into a different voltage. The integrated circuit includes a current regulator that can switch between a first state in which a part of a current flowing through the power supply path flows to an input terminal and a second state in which a current flowing to the input terminal is lower than that of the first state, a controller power supply that converts a voltage into a driving voltage and supplies the driving voltage to the controller, a connection terminal for connecting an auxiliary power supply used for generating the driving voltage, and a protection circuit that blocks or decreases, when an auxiliary power supply voltage of the auxiliary power supply decreases, a current flowing to the input terminal.