Abstract: A starter (1) includes a motor unit (3), an output shaft (4) configured to receive a rotational force of the motor unit (3) and rotate, a pinion gear (74) (a pinion mechanism) helically engageable with a ring gear (23) of an engine, a clutch mechanism (5) configured to transmit the rotational force of the output shaft (4) to the pinion gear (74), and an electromagnetic device (9) configured to bias a pressing force toward the ring gear (23) to the clutch mechanism (5) and the pinion gear (74), wherein a plunger spring (91) (a backlash absorption mechanism) configured to bring one end (81a) (a point of action) of a plunger inner part (81) in constant elastic contact with the clutch mechanism (5) is installed at the electromagnetic device (9).

Abstract: A starter includes an output shaft which rotates by a rotary force applied from the motor unit, a housing in which an end of the output shaft is rotatably supported, and an electromagnetic device configured to apply/shut off current to the motor unit, and biases a suppressing force toward the ring gear to the pinion gear through a clutch mechanism, wherein a load receiving member which abuts one end of the output shaft to receive an axial load generated from the output shaft is installed in the housing.

Abstract: A starter includes a motor section; an output shaft which rotates with receiving a rotational force of the motor section; a gear mechanism which transmits the rotational force of the output shaft to a ring gear of an engine; and a switch unit which performs electrical connection and disconnection to the motor section. Thus, the output shaft, the gear mechanism and the switch unit are accommodated in a housing, and a groove section for weakening the stiffness of the housing is formed in housing at a position which avoids a position where the switch unit is arranged.

Abstract: A starter (1) includes a motor unit (3), an output shaft (4) configured to receive a rotational force of the motor unit (3) and rotate, a pinion gear (74) (a pinion mechanism) helically engageable with a ring gear (23) of an engine, a clutch mechanism (5) configured to transmit the rotational force of the output shaft (4) to the pinion gear (74), and an electromagnetic device (9) configured to bias a pressing force toward the ring gear (23) to the clutch mechanism (5) and the pinion gear (74), wherein a plunger spring (91) (a backlash absorption mechanism) configured to bring one end (81a) (a point of action) of a plunger inner part (81) in constant elastic contact with the clutch mechanism (5) is installed at the electromagnetic device (9).

Abstract: A starter includes a motor section; an output shaft which rotates with receiving a rotational force of the motor section; a gear mechanism which transmits the rotational force of the output shaft to a ring gear of an engine; and a switch unit which performs electrical connection and disconnection to the motor section. Thus, the output shaft, the gear mechanism and the switch unit are accommodated in a housing, and a groove section for weakening the stiffness of the housing is formed in housing at a position which avoids a position where the switch unit is arranged.

Abstract: In a coaxial engine starter comprising a pinion (6) connected to the output shaft (4) which is driven by an electric motor (3), via a helical spline (19), a switch unit (7) for selectively closing a power supply line to the electric motor, and a solenoid device (9) consisting of an annular armature and an annular energization coil surrounding the output shaft to axially drive the pinion and a moveable contact of the switch unit in the axial direction, the switch is adapted to be closed before the pinion is actuated by the solenoid device. Therefore, the output requirement for the solenoid device can be reduced as opposed to the conventional starter in which the pinion is actuated strictly by the solenoid device, and the size of the engine starter can be reduced.

Abstract: In an engine starter comprising a pinion slidably fitted on the output shaft for driving a ring gear of an engine that is to be started, and a one-way clutch having a first end secured to the pinion and a second end which is engaged by the output shaft via spline means, a compression coil spring is interposed between a stopper secured to the output shaft and an annular shoulder defined in a cylindrical extension of the second end of the one-way clutch. Therefore, even when the pinion is forced into a high speed rotation by the engine which has been started by the engine starter, the pinion simply rotates freely, and no friction is applied to the compression coil spring or the stopper.

Abstract: In a coaxial engine starter comprising a pinion connected to the output shaft which is driven by an electric motor, via a helical spline, a switch unit for selectively closing a power supply line to the electric motor, and a solenoid device consisting of an annular armature and an annular energization coil surrounding the output shaft to axially drive the pinion and a moveable contact of the switch unit in the axial direction, the energization coil is disposed between the electric motor and the pinion with a commutator of the electric motor facing the energization coil, and a pigtail for one of the brushes is directly connected to the moveable contact. Also, the contacts of the switch unit are placed between a pair of adjacent brushes of the commutator.

Abstract: A plurality of square projections 26 are arranged in two mutually perpendicular directions at the pitch of P on to the surface of a plate member 27 between a first group of punched recesses 29a. The pitch P is twice the length of a side of each punched recess 29a. Shifted with respect to the first group of punched recesses 29a by P/2 in both the vertical and horizontal directions is a second group of punched recesses 29b. The punched recesses 29a and 29b define the projections 26 in the parts which are not occupied by these recesses generally in the pattern of a checker board. Because the projections 26 are separated from each other, and can effectively dissipate heat therefrom, the increase in the contact resistance due to heat generation can be prevented, and the efficiency of the starter motor can be increased.

Abstract: The capability of heat dissipation from the contact surface of a magnetic switch for a starter motor is improved without increasing the fabrication cost. A punch 28 having a plurality of square projections arranged in two mutually perpendicular directions at the pitch of P is applied to the surface of a plate member 27 to form a first group of punched recesses 29a. The pitch P is twice the length of a side of each punched recess 29a. Then, the punch 28 is shifted with respect to the first group of punched recesses 29 by P/2 in both the vertical and horizontal directions before forming a second group of punched recesses 29b. The punched recesses 29a and 29b define projections 26 in the parts which are not occupied by these recesses generally in the pattern of a checker board.