Abstract: Outer circumference of a rotor is alternately provided with a plurality of circumferential portions and a plurality of convex portions. Straight lines each connecting a rotational axis to one of circumferential centers of circumferential portions are referred to as radial lines. Straight lines each bisecting one of convex portions are referred to as bisectors. A plurality of magnetic flux blocking regions are located on a rotor. One of the magnetic flux blocking region is located in a range between the radial line and the bisector adjacent to and preceding the radial line in the rotation direction. Therefore, a permanent magnet embedment rotating electric machine is capable of preventing decreases in torque and suppressing torque ripple.

Abstract: A plurality of convex portions are located inside of a virtual circumferential surface. Each convex portion connects an adjacent pair of circumferential portions with each other. Each convex portion is an arcuate curve bulging radially outward. Each convex portion defines a minimum radius. A difference between a radius R and the minimum radius is a depth Dh. Dhr=Dh×25.5/R. A range of an angular width A in relation to circumferential portion and a range of the depth Dh are set by the following expression, (5.6×Dhr+11.3)°×6/p?A<35°×6/p and A<[360/p?2×arccos]°??(1) Therefore, decrease in torque is prevented. Torque pulsation is suppressed.

Abstract: A stator includes a first through a third windings, and a first and a second interphase insulators. The first interphase insulator has a first pair of strip-shaped insulating sheets and a first connecting portion. End portions of the insulating sheets are connected to the respective opposite end portions to form joints. The first connecting portion connects the insulating sheets so that the joints are shifted so as to be disposed in a region avoiding an interference with the first winding on both of a lead-extending side and the opposite side. In the second interphase insulator similarly constructed, a second connecting portion connects a second pair of the strip-shaped insulating sheets so that joints are shifted so as to be disposed in a region avoiding an interference with the third winding on both of the lead-extending side and the opposite side.

Abstract: A stator of an electric motor includes teeth, coils each wound about one of the teeth, and a yoke. Each tooth includes a tooth main body and a tooth reinforcing portion, which is integrally molded with at least a part of the surface of the tooth main body. The tooth main portions are formed a powder magnetic core material. The tooth reinforcing portions have a higher mechanical strength than that of the tooth main bodies. The yoke has fitting openings each receiving one of the teeth. Each tooth is fitted to the corresponding fitting opening in such a manner that the tooth reinforcing portion contacts a wall surface that defines the fitting opening.

Abstract: A housing of an electric motor includes an inner circumferential surface, which includes recesses arranged along the circumferential direction. On an outer circumferential surface of a stator core of a stator are provided protrusions arranged along the circumferential direction. Fitting each protrusion to the corresponding recess fixes the stator core to the housing. A rotor is provided radially inward of the stator. In a state where each protrusion is fitted to the corresponding recess, a pair of side surfaces of each protrusion are retained by a pair of inner side surfaces of the corresponding recess in the circumferential direction of the housing. A gap is formed between an end face of each protrusion and an inner bottom surface of the corresponding recess facing the end face along the entire surface of the end face.

Abstract: A stator includes a cylindrical stator core and a coil. The stator core is formed by stacking a plurality of core sheets. The stator core has a groove formed in an outer circumferential surface thereof and a slot. The coil is inserted in the slot. The groove is located parallel to an axis of the stator core and the slot is skewed with respect to the axis.

Abstract: A rotating electric machine including circumferential portions respectively corresponding to magnetic pole centers of permanent magnets and defined along the outer circumference of the rotor at a plurality of locations, with each circumferential portion extending along part of a virtual circumferential surface, which is coaxial with the rotor. The circumferential portions are spaced from one another in the circumferential direction. Convex portions connect adjacent pairs of the circumferential portions. Each convex portion is located radially inward from the circumferential surface, projects in a radially outward direction, and includes angled portions directed in the radially outward direction. The rotating electric machine suppresses decrease in the average value of the output torque and does not use reluctance torque to increase the average value of the output torque.

Abstract: A stator includes a first through a third windings, and a first and a second interphase insulators. The first interphase insulator has a first pair of strip-shaped insulating sheets and a first connecting portion. End portions of the insulating sheets are connected to the respective opposite end portions to form joints. The first connecting portion connects the insulating sheets so that the joints are shifted so as to be disposed in a region avoiding an interference with the first winding on both of a lead-extending side and the opposite side. In the second interphase insulator similarly constructed, a second connecting portion connects a second pair of the strip-shaped insulating sheets so that joints are shifted so as to be disposed in a region avoiding an interference with the third winding on both of the lead-extending side and the opposite side.

Abstract: A stator of an electric motor includes teeth, coils each wound about one of the teeth, and a yoke. Each tooth includes a tooth main body and a tooth reinforcing portion, which is integrally molded with at least a part of the surface of the tooth main body. The tooth main portions are formed a powder magnetic core material. The tooth reinforcing portions have a higher mechanical strength than that of the tooth main bodies. The yoke has fitting openings each receiving one of the teeth. Each tooth is fitted to the corresponding fitting opening in such a manner that the tooth reinforcing portion contacts a wall surface that defines the fitting opening.

Abstract: A housing of an electric motor includes an inner circumferential surface, which includes recesses arranged along the circumferential direction. On an outer circumferential surface of a stator core of a stator are provided protrusions arranged along the circumferential direction. Fitting each protrusion to the corresponding recess fixes the stator core to the housing. A rotor is provided radially inward of the stator. In a state where each protrusion is fitted to the corresponding recess, a pair of side surfaces of each protrusion are retained by a pair of inner side surfaces of the corresponding recess in the circumferential direction of the housing. A gap is formed between an end face of each protrusion and an inner bottom surface of the corresponding recess facing the end face along the entire surface of the end face.

Abstract: Outer circumference of a rotor is alternately provided with a plurality of circumferential portions and a plurality of convex portions. Straight lines each connecting a rotational axis to one of circumferential centers of circumferential portions are referred to as radial lines. Straight lines each bisecting one of convex portions are referred to as bisectors. A plurality of magnetic flux blocking regions are located on a rotor. One of the magnetic flux blocking region is located in a range between the radial line and the bisector adjacent to and preceding the radial line in the rotation direction. Therefore, a permanent magnet embedment rotating electric machine is capable of preventing decreases in torque and suppressing torque ripple.

Abstract: A power transmission device includes a first one-way clutch that transmits a rotational power of a pulley to a rotating shaft, and a second one-way clutch that transmits a rotational power of a rotor of a motor to the rotating shaft. The first one-way clutch is of inner cam type in which an engagement cam-surface is formed in an outer periphery of a first inner ring, while the second one-way clutch is of outer cam type in which an engagement cam-surface is formed in an inner periphery of a second outer ring. This arrangement improves engagement performance of the first one-way clutch as well as reducing heat generation of the second one-way clutch, so that the lifetime of grease is prolonged.

Abstract: An electric motor includes an annular housing and an annular stator core having the inner periphery the shape of which differs from a perfect circle. The stator core is supported by the housing in such a manner that the outer periphery of the stator core and the inner periphery of the housing are partially in contact with each other. The inner periphery of the stator core is deformed to become close to the shape of the perfect circle when the stator core is securely fitted in the housing by shrink fitting.

Abstract: A plurality of convex portions are located inside of a virtual circumferential surface. Each convex portion connects an adjacent pair of circumferential portions with each other. Each convex portion is an arcuate curve bulging radially outward. Each convex portion defines a minimum radius. A difference between a radius R and the minimum radius is a depth Dh. Dhr=Dh×25.5/R. A range of an angular width A in relation to circumferential portion and a range of the depth Dh are set by the following expression, (5.6×Dhr+11.3)°×6/p?A<35°×6/p and A<[360/p?2×arccos]° ??(1) Therefore, decrease in torque is prevented. Torque pulsation is suppressed.

Abstract: There is provided a one-way clutch unit that is simple in structure and compact. An annular recess 67 is provided in an inner periphery of a side of a deep groove ball bearing portion 55 of a first inner ring 7 of a first one-way clutch 1, and an end portion on the side of a deep groove ball bearing portion 65 of a second one-way clutch 2 is disposed in the annular recess 67. Thereby, the dimension in an axial direction of the one-way clutch unit is reduced by a dimension in the axial direction of the second one-way clutch 2 that is disposed in the annular recess 67.

Abstract: A stator includes a cylindrical stator core and a coil. The stator core is formed by stacking a plurality of core sheets. The stator core has a groove formed in an outer circumferential surface thereof and a slot. The coil is inserted in the slot. The groove is located parallel to an axis of the stator core and the slot is skewed with respect to the axis.

Abstract: A rotating electric machine including circumferential portions respectively corresponding to magnetic pole centers of permanent magnets and defined along the outer circumference of the rotor at a plurality of locations, with each circumferential portion extending along part of a virtual circumferential surface, which is coaxial with the rotor. The circumferential portions are spaced from one another in the circumferential direction. Convex portions connect adjacent pairs of the circumferential portions. Each convex portion is located radially inward from the circumferential surface, projects in a radially outward direction, and includes angled portions directed in the radially outward direction. The rotating electric machine suppresses decrease in the average value of the output torque and does not use reluctance torque to increase the average value of the output torque.

Abstract: A compressor provided with a torque limiter constructed such that, in view of possible occurrence of accidental locking of the compressor, in the case where a one-way clutch is used in place of an electromagnetic clutch in order to permit a refrigerant compressor for a vehicle air-conditioning system to be driven by an electric motor instead of an internal combustion engine, when an excessive torque is to be transmitted by the one-way clutch, rollers ride over wedge surfaces and fall into pocket sections, or sprags are reversed to roll-over.

Abstract: An electric motor includes a stator and a rotor disposed surrounding the stator and being rotatable around the stator. The rotor has a plurality of permanent magnets each of which is movable in a radial direction of the rotor. The radially outward movement of the permanent magnets is urged by centrifugal force caused by the rotation of the rotor.

Abstract: There is provided a compact one-way clutch unit that can perform connection and disconnection of power in two systems. An end portion on a side of a deep groove ball bearing portion 65 of a second one-way clutch 2 is disposed in an annular recess 67, which is provided at an end portion in an inner peripheral surface of a first inner ring 7, so that the dimension in an axial direction of a one-way clutch unit is reduced. Further, an outer peripheral diameter on a side of the deep groove ball bearing portion 65 is made smaller than that on the side of a one-way clutch portion 60 of a second outer ring 14 so as to reduce a diameter of the recess 67 and the outer peripheral diameter of the first outer ring 5 of the first one-way clutch 1.