Abstract: A method of manufacturing a coil includes: a first step of connecting a plurality of first coils to one end of respective a plurality of connecting members; and a second step of inserting the first coils, which are connected to the respective connecting members, and a plurality of second coils into slots of a stator core, so that the second coils are connected to the respective connecting members, which have already been connected to the first coils. Further, in the second step, in a case where insert directions of the two first coils adjacent to each other to be inserted into the slots are different from each other, a sum of insertion amounts of the two first coils adjacent to each other is less than a total length of each of the slots.

Abstract: A conductor wire insulating film separating method disclosed includes: a preparing step involving preparing rectangular cross-section coil pieces each of which is a conductor wire coated with insulating film and used to provide a stator coil of rotary electric machine; a delivering-in step involving, after the preparing step, delivering coil pieces into a laser separator, with coil pieces aligned such that extremities thereof are adjacent to each other; an applying step involving, after the delivering-in step, continuously applying film removing laser to the extremities of the aligned coil pieces such that the laser is applied to one extremity and then to another extremity, thus removing at least portions of the insulating film from the extremities of the coil pieces; and a delivering-out step involving delivering the coil pieces, from which the at least portions of the insulating film have been removed by the applying step, out of the laser separator.

Abstract: A stator manufacturing method includes an inserting step of inserting lead-side segment coils covered with an insulating film and lead-opposite-side segment coils covered with an insulating film into a plurality of slots formed between a plurality of teeth radially protruding from an annular yoke, along the axial direction of the yoke, and electrically connecting the segment coils by using connecting members, in the inserting step, the plurality of segment coils are collectively inserted into the slots, and the method further includes an exposing step of forming the segment coils with exposed conductor portions by forming holes penetrating the insulating films in crossover parts of the segment coils while the segment coils are inserted in the slots.

Abstract: A Schnuerle scavenging two-stroke engine is provided that can keep combustion stability in a wide rotation speed range while suppressing blow-by. The engine of the present invention is a Schnuerle scavenging two-stroke engine (2). A scavenging passage (14(in1)) related to at least one scavenging port (16(in1)) has, at its upper end portion (14a(in1)), an intake-side wall surface (204). The intake-side wall surface (204) defines a first flow direction (42) of scavenging gas discharged from the scavenging port (16(in1)) at a height level of the scavenging port (16(in1)). The upper end portion (14a(in1)) of the scavenging passage (14(in1)) related to the scavenging port (16(in1)) has a guide portion (50) defining a second flow direction (44) of scavenging gas discharged from the scavenging port (16(in1)). The second flow direction (44) is deflected to the intake side from the first flow direction (42) at the height level of the scavenging port (16(in1)).

Abstract: A Schnuerle scavenging two-stroke engine is provided that can keep combustion stability in a wide rotation speed range while suppressing blow-by. The engine of the present invention is a Schnuerle scavenging two-stroke engine (2). A scavenging passage (14(in1)) related to at least one scavenging port (16(in1)) has, at its upper end portion (14a(in1)), an intake-side wall surface (204). The intake-side wall surface (204) defines a first flow direction (42) of scavenging gas discharged from the scavenging port (16(in1)) at a height level of the scavenging port (16(in1)). The upper end portion (14a(in1)) of the scavenging passage (14(in1)) related to the scavenging port (16(in1)) has a guide portion (50) defining a second flow direction (44) of scavenging gas discharged from the scavenging port (16(in1)). The second flow direction (44) is deflected to the intake side from the first flow direction (42) at the height level of the scavenging port (16(in1)).

Abstract: A stator has a stator core composed of teeth and slots. Segment coils are inserted into the corresponding slots. The segment coil projecting from the slot has an exposed conductor part and a covered conductor part covered with an electrical insulation film. The exposed conductor part is arranged at the distal end side from the covered conductor part of the segment coil. The segment coils are connected together through the exposed conductor parts thereof projecting from the slots. The exposed conductor part has a thickness T2 thinner than a thickness T1 of the covered conductor part. A step part is formed at a position of the stator core side, adjacent to the exposed conductor part of the segment coil. The step part and the covered conductor part are covered with the electrical insulation film continuously from the stator core side of the covered conductor part.

Abstract: Two-cycle engine includes cylinder block formed with a cylinder and crank chamber. The cylinder block includes: an exhaust passage leading to a combustion chamber in the cylinder through an exhaust port opened to an inner circumferential surface of the cylinder; a scavenging port opened to the inner circumferential surface of the cylinder; a communication passage extending from the scavenging port in a radial direction of the cylinder; and a scavenging passage extending in an axial direction of the cylinder, communicating with the crank chamber, and having an opening portion formed in a bottom surface of the communication passage. A ceiling surface of the communication passage is inclined toward a cylinder head with increasing distance from a scavenging passage side thereof toward the scavenging port. A bottom surface of the communication passage is inclined toward the crank chamber with increasing distance from a scavenging passage side thereof toward the scavenging port.

Abstract: Among multiple scavenging passages 14 included in a cylinder, a scavenging passage connected to at least one scavenging port 16 constitutes a variable scavenging passage 14(ch). An upper end portion of the variable scavenging passage 14(ch) has a guide surface 50 defining a discharge direction of a scavenging gas discharged from a variable scavenging port 16(ch) connected thereto on a horizontal plane. The guide surface 50 includes at least a first guide portion 50(H) defining a first discharge direction of the scavenging gas and a second guide portion 50(L) defining a second discharge direction of the scavenging gas. The discharge direction of the scavenging gas is changed from the first discharge direction to the second discharge direction on the horizontal plane by the first and second guide portions 50(H) and 50(L) in the scavenging stroke.

Abstract: Two-cycle engine includes cylinder block formed with a cylinder and crank chamber. The cylinder block includes: an exhaust passage leading to a combustion chamber in the cylinder through an exhaust port opened to an inner circumferential surface of the cylinder; a scavenging port opened to the inner circumferential surface of the cylinder; a communication passage extending from the scavenging port in a radial direction of the cylinder; and a scavenging passage extending in an axial direction of the cylinder, communicating with the crank chamber, and having an opening portion formed in a bottom surface of the communication passage. A ceiling surface of the communication passage is inclined toward a cylinder head with increasing distance from a scavenging passage side thereof toward the scavenging port. A bottom surface of the communication passage is inclined toward the crank chamber with increasing distance from a scavenging passage side thereof toward the scavenging port.

Abstract: A conductor wire insulating film separating method disclosed includes: a preparing step involving preparing rectangular cross-section coil pieces each of which is a conductor wire coated with insulating film and used to provide a stator coil of rotary electric machine; a delivering-in step involving, after the preparing step, delivering coil pieces into a laser separator, with coil pieces aligned such that extremities thereof are adjacent to each other; an applying step involving, after the delivering-in step, continuously applying film removing laser to the extremities of the aligned coil pieces such that the laser is applied to one extremity and then to another extremity, thus removing at least portions of the insulating film from the extremities of the coil pieces; and a delivering-out step involving delivering the coil pieces, from which the at least portions of the insulating film have been removed by the applying step, out of the laser separator.

Abstract: A method of removing an insulating coating layer of coil wiring includes: a fragmentation step in which a line-shaped region of the insulating coating layer, which separates a removal-planned portion and a remain-planned portion of the insulating coating layer, is removed; a laser irradiation step in which laser light which transmits through the insulating coating layer but which is absorbed by a coil wiring is irradiated from a side of an outer surface of the removal-planned portion toward a boundary of the coil wiring with the insulating coating layer, to carbonize a boundary portion between the insulating coating layer and the coil wiring of the removal-planned portion by generation of heat of the coil wiring; and a coating turn-over step in which air is blown onto the removal-planned portion to turn over and blow off the removal-planned portion.

Abstract: Among multiple scavenging passages 14 included in a cylinder, a scavenging passage connected to at least one scavenging port 16 constitutes a variable scavenging passage 14(ch). An upper end portion of the variable scavenging passage 14(ch) has a guide surface 50 defining a discharge direction of a scavenging gas discharged from a variable scavenging port 16(ch) connected thereto on a horizontal plane. The guide surface 50 includes at least a first guide portion 50(H) defining a first discharge direction of the scavenging gas and a second guide portion 50(L) defining a second discharge direction of the scavenging gas. The discharge direction of the scavenging gas is changed from the first discharge direction to the second discharge direction on the horizontal plane by the first and second guide portions 50(H) and 50(L) in the scavenging stroke.

Abstract: An insulation film peeling method which radiates laser light onto a front end portion of an insulation film-coated conducting wire including a conducting wire and an insulation film in a longitudinal direction, and which peels a part of the insulation film up to a peeling boundary of a predetermined regulated peeling length, includes performing a rectilinear scan of a first region, in which a radiation position of the laser light moves from one side toward the other side and then moves from the other side toward the one side upon reaching the other side, and performing a unidirectional scan of a second region, in which the radiation of the laser light is performed from one side toward the other side and then the radiation position returns to the one side in a state in which the radiation of the laser light stops upon reaching the other side.

Abstract: A stator has a stator core composed of teeth and slots. Segment coils are inserted into the corresponding slots. The segment coil projecting from the slot has an exposed conductor part and a covered conductor part covered with an electrical insulation film. The exposed conductor part is arranged at the distal end side from the covered conductor part of the segment coil. The segment coils are connected together through the exposed conductor parts thereof projecting from the slots. The exposed conductor part has a thickness T2 thinner than a thickness T1 of the covered conductor part. A step part is formed at a position of the stator core side, adjacent to the exposed conductor part of the segment coil. The step part and the covered conductor part are covered with the electrical insulation film continuously from the stator core side of the covered conductor part.

Abstract: Provided is a stratified scavenging engine and a portable work machine that suppress THC sufficiently. A stratified scavenging engine includes: a cylinder having a cylinder bore; and a piston stored in the cylinder bore to be movable in a reciprocating manner. The cylinder has an intake port to intake leading air and a scavenging port to scavenge combustion gas, the intake port and the scavenging port being open to the cylinder bore. The piston has a peripheral surface including a piston groove to guide leading air from the intake port to the scavenging port, and the piston groove has a recess near the intake port.

Abstract: A method of removing an insulating coating layer of coil wiring includes: a fragmentation step in which a line-shaped region of the insulating coating layer, which separates a removal-planned portion and a remain-planned portion of the insulating coating layer, is removed; a laser irradiation step in which laser light which transmits through the insulating coating layer but which is absorbed by a coil wiring is irradiated from a side of an outer surface of the removal-planned portion toward a boundary of the coil wiring with the insulating coating layer, to carbonize a boundary portion between the insulating coating layer and the coil wiring of the removal-planned portion by generation of heat of the coil wiring; and a coating turn-over step in which air is blown onto the removal-planned portion to turn over and blow off the removal-planned portion.

Abstract: Provided is a stratified scavenging engine and a portable work machine that suppress THC sufficiently. A stratified scavenging engine includes: a cylinder having a cylinder bore; and a piston stored in the cylinder bore to be movable in a reciprocating manner. The cylinder has an intake port to intake leading air and a scavenging port to scavenge combustion gas, the intake port and the scavenging port being open to the cylinder bore. The piston has a peripheral surface including a piston groove to guide leading air from the intake port to the scavenging port, and the piston groove has a recess near the intake port.

Abstract: An electric power supply system includes a first battery provided in an electric power supply circuit; a second battery provided in the circuit and electrically connected in parallel to the first battery, the second battery being a lithium-ion battery; an electric load provided in the circuit and electrically connected in parallel to the first battery and the second battery; a switch provided in the circuit, and configured to electrically disconnect the second battery from the circuit when the switch is open; and a control device configured to open the switch when an ignition switch is on and an SOC of the first battery is equal to or higher than a prescribed SOC, and to execute an open-circuit voltage acquisition process that acquires an open-circuit voltage of the second battery after a lapse of a prescribed time from a time when the switch is opened.

Abstract: An insulation film peeling method which radiates laser light onto a front end portion of an insulation film-coated conducting wire including a conducting wire and an insulation film in a longitudinal direction, and which peels a part of the insulation film up to a peeling boundary of a predetermined regulated peeling length, includes performing a rectilinear scan of a first region, in which a radiation position of the laser light moves from one side toward the other side and then moves from the other side toward the one side upon reaching the other side, and performing a unidirectional scan of a second region, in which the radiation of the laser light is performed from one side toward the other side and then the radiation position returns to the one side in a state in which the radiation of the laser light stops upon reaching the other side.

Abstract: An electric power supply system includes a first battery provided in an electric power supply circuit; a second battery provided in the circuit and electrically connected in parallel to the first battery, the second battery being a lithium-ion battery; an electric load provided in the circuit and electrically connected in parallel to the first battery and the second battery; a switch provided in the circuit, and configured to electrically disconnect the second battery from the circuit when the switch is open; and a control device configured to open the switch when an ignition switch is on and an SOC of the first battery is equal to or higher than a prescribed SOC, and to execute an open-circuit voltage acquisition process that acquires an open-circuit voltage of the second battery after a lapse of a prescribed time from a time when the switch is opened.