Abstract: The invention includes a stator disposed inside a yoke, an armature supported inside the stator, a commutator connected to the armature and having a sliding surface in an outer peripheral portion, and a brush disposed opposing the commutator and having a sliding contact surface that comes into sliding contact with the sliding surface of the commutator, wherein the brush has a first member, and a second member with an electrical resistance value higher than that of the first member, the first member is disposed on an entrance side and the second member on an exit side with respect to a direction of rotation of the commutator, and the sliding contact surface of the brush is such that an inclined portion that inclines toward the entrance side with respect to the direction of rotation of the commutator is formed in the first member.

Abstract: The invention includes a stator disposed inside a yoke, an armature supported inside the stator, a commutator connected to the armature and having a sliding surface in an outer peripheral portion, and a brush disposed opposing the commutator and having a sliding contact surface that comes into sliding contact with the sliding surface of the commutator, wherein the brush has a first member, and a second member with an electrical resistance value higher than that of the first member, the first member is disposed on an entrance side and the second member on an exit side with respect to a direction of rotation of the commutator, and the sliding contact surface of the brush is such that an inclined portion that inclines toward the entrance side with respect to the direction of rotation of the commutator is formed in the first member.

Abstract: Obtained is an engine starter having a structure in which, even when frictional heat is generated on a roller due to sliding of a roller and a clutch inner with respect to each other, deformation of a rolling contact surface of the roller is reduced by suppressing reduction in hardness of the rolling contact surface of the roller due to the frictional heat, thereby making it possible to improve transmission of a rotation force from a clutch outer to a clutch inner. The engine starter includes a clutch (5) for transmitting a rotation force of an output shaft (4) to a pinion gear (7), a clutch outer (10), a clutch inner (11) having one end portion facing an inner portion of the clutch outer (10) and another end portion to which the pinion gear (7) is fixed, and a roller (12) which rolls while being provided between the clutch outer (10) and the clutch inner (11). The clutch outer (10) is formed with a notch portion (10a) of a tapered shape.

Abstract: Rollers and springs are installed in notch portions of a clutch outer (S104), an inscribed circle diameter of the rollers is measured in a state in which the rollers are placed in contact with stopping portions by pressure from the springs (S105), and an outside diameter of a cylindrical portion is determined from the inscribed circle diameter measured value such that a predetermined amount of roller bite is achieved (S106). Then, the outside diameter of the cylindrical portion is finished so as to have the determined value of the outside diameter (S108). An overrunning clutch is assembled by pairing together the clutch outer, rollers, and springs and the clutch inner (S110).

Abstract: A motor which, even if the commutator is deformed, suppresses brush deformation to thereby prevent short-circuiting between the positive-pole-side brush and the motor housing. A motor includes: a motor housing; a stator; a rotor; a commutator; a positive-pole-side brush; a negative-pole-side brush; and a brush holding frame fixed to the motor housing and having a positive-pole-side brush holding portion holding the positive-pole-side brush and a negative-pole-side brush holding portion holding the negative-pole-side brush, in which the positive-pole-side brush holding portion and the negative-pole-side brush holding portion each curve about a circumference of the commutator, and in which a thickness of an outer portion of the positive-pole-side brush holding portion in a circumferential direction of the commutator is greater than a thickness of an outer portion of the negative-pole-side brush holding portion in the circumferential direction of the commutator.

Abstract: Disclosed is a motor which, even if the commutator is deformed, suppresses brush deformation to thereby prevent short-circuiting between the positive-pole-side brush and the motor housing.

Abstract: Obtained is an engine starter having a structure in which, even when frictional heat is generated on a roller due to sliding of a roller and a clutch inner with respect to each other, deformation of a rolling contact surface of the roller is reduced by suppressing reduction in hardness of the rolling contact surface of the roller due to the frictional heat, thereby making it possible to improve transmission of a rotation force from a clutch outer to a clutch inner. The engine starter includes a clutch (5) for transmitting a rotation force of an output shaft (4) to a pinion gear (7), a clutch outer (10), a clutch inner (11) having one end portion facing an inner portion of the clutch outer (10) and another end portion to which the pinion gear (7) is fixed, and a roller (12) which rolls while being provided between the clutch outer (10) and the clutch inner (11). The clutch outer (10) is formed with a notch portion (10a) of a tapered shape.

Abstract: Rollers and springs are installed in notch portions of a clutch outer (S104), an inscribed circle diameter of the rollers is measured in a state in which the rollers are placed in contact with stopping portions by pressure from the springs (S105), and an outside diameter of a cylindrical portion is determined from the inscribed circle diameter measured value such that a predetermined amount of roller bite is achieved (S106). Then, the outside diameter of the cylindrical portion is finished so as to have the determined value of the outside diameter (S108). An overrunning clutch is assembled by pairing together the clutch outer, rollers, and springs and the clutch inner (S110).

Abstract: To prevent an attracting force to the plunger from becoming insufficient, at least one of an output shaft and a thrust spline is formed from magnetic material having a lower relative permeability than iron.

Abstract: To secure sufficient attractive force against a plunger, an overrunning clutch is arranged so that one end of a thrust spline is positioned so as to maintain a prescribed interval from the end of the plunger in the condition where the plunger is unexcited by an exciting coil and the outside periphery of the output shaft corresponding to the prescribed interval is covered by a cylinder body formed of a non-magnetic material or less permeable material.

Abstract: To reduce abrasion of the pinion and the ring gear, a coil spring and a plate are arranged between the inner circumference of the plunger and the output shaft. The plate is adapted to the rear end of the thrust spline of the over-running clutch to transmit the elastic force of the coil spring to the thrust spline.

Abstract: To fully secure the precision around an output shaft, an electromagnet is axially held in position between a center bracket and a front bracket which form an enclosing member for a starter.

Abstract: To prevent damage or breakage of a pinion return coil spring employed in a starter, it is held between a first stopper and a second stopper which are coaxially arranged relative to an output shaft. Each stopper is provided with a cylindrical portion for restricting an inner diameter of the pinion return coil spring and controlling the movement of the pinion.

Abstract: To prevent powder caused by wear of brushes from entering a contact chamber, a first stationary contact is electrically connected to a battery and a second stationary contact is connected to positive brushes, wherein a contact bracket is provided to hold the first stationary contact, and a contact chamber cover is provided to interpose and hold the second stationary contact between the contact chamber cover and the contact bracket so that the contact chamber can be kept in an airtight state.

Abstract: A starter in which a terminal is each provided for a motor side fixed contact point and an excitation coil separately, and the terminal of the motor side fixed contact point and the terminal of the excitation coil are of a snap-on type. Therefore, the work efficiency of connecting the motor side fixed contact point and the excitation coil of the electromagnetic switch can be improved.

Abstract: A contact shaft moving device that reduces the wearing of a pinion in a ring gear. More specifically, the contact shaft moving device moves a contact shaft in such a direction as to cause a moving contact to be in direct contact with a stationary contact after a plunger is attracted and moved for a certain period of time by an exiting coil. The movement of the plunger also assists in moving the pinion into abutment with the ring gear prior to contact between the moveable and stationary contacts.