JPS61250385A - Starter - Google Patents

Abstract

PURPOSE:To enable engaging performance between a pinion and a ring gear to improve by arranging a contact pressure spring between a shaft, having a movable contact, and a plunger so as to contract said spring in case the pinion gets behind to plunge out. CONSTITUTION:A contact pressure spring 17 is arranged between a shaft 8 having a movable contact 10 and a plunger 7, by which even if a drive spring 27 is deformed and a pinion 23 gets behind to plunge out due to inertial weight of an overrunning clutch 22, the pinion 23 and the like, the contact pressure spring 17 contracts and movement of a movable contact 10 is delayed to improve engagement between the pinion 23 and a ring gear 24 while shock can be absorbed by the drive spring 27 in case the pinion 23 clashes on the ring gear 24. Still more, the number of parts can be prevented from increasing since the contact pressure spring 17 is used.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to improving the meshing properties between a pinion in a starter and a ring gear of an internal combustion engine.

(Prior art) In a conventional magnetic switch that uses a plunger to move the pinion toward the ring gear, the attraction of the excitation coil of the magnetic switch during startup attempts to move the pinion toward the ring gear by moving the plunger. However, due to the inertial weight of the overrunning clutch and pinion, the drive spring is bent. Therefore, the contact of the magnetic switch closes and the starter motor is energized before it reaches the pinion or ring gear, and by the time the pinion engages with the ring gear. , the pinion increases to a considerable rotational speed, and the impact when the pinion meshes with the ring gear becomes large.

Therefore, as shown in Japanese Utility Model Publication No. 58-7090, a drive spring is attached to the inner circumference of the plunger that engages a lever that moves the pinion toward the ring gear at one end.
A biased first movable body is housed, and a second movable body having a movable contact at one end is movably provided within the fixed core. Furthermore, a compression spring is disposed between the plunger and the fixed iron core. The distance between the plunger and the fixed core is set smaller than the distance between the first movable body and the second movable body.

Therefore, even when the plunger is attracted by the excitation coil, the drive spring is made stronger than the compression spring, so the drive spring does not bend first, and the compression spring contracts and the plunger moves, causing the pinion to move. Before meshing with the ring gear, the movable contact and the fixed contact contact each other to prevent the starter motor from being energized and improve the meshing performance between the pinion and the ring gear.

(Problem to be Solved by the Invention) However, in the conventional drive spring, when the pinion is moved to the ring gear side by the plunger via the lever, the impact force generated when the end faces of the pinion and the ring gear collide with each other. However, since the drive spring was prevented from deflecting in the conventional drive spring described above, the problem was that the impact force was concentrated on the lever. . Further, it is necessary to provide a first movable body having a plunger center and a second movable body having a movable contact, resulting in a problem that the number of parts increases.

Therefore, the present invention improves the meshing properties between the pinion and the ring gear without increasing the number of parts.

(Means for Solving the Problem) A starter motor, a pinion to which the rotation of the starter motor is transmitted and meshes with a ring gear of an internal combustion engine, an excitation coil, which is moved by energization of the excitation coil, and the pinion is connected to the ring gear. a plunger to be moved to the side; a shaft having a movable contact at one end and disposed coaxially with the plunger; and a fixed contact for energizing the starter motor when the movable contact of the shaft comes into contact with the plunger. and a contact pressure spring disposed between the shaft and the plunger to obtain a predetermined contact pressure between the movable contact and the fixed contact.

(Function) Even if the excitation coil attracts the inside of the plunger and the drive shaft bends, the contact pressure spring also bends, preventing the shaft from moving in the axial direction.

(Example) The present invention will be described below with reference to embodiments shown in the drawings.

In the figure, ■ is a starter motor, and 2 is a magnet switch. 3 is the yoke of the magnetic switch,
An excitation coil 5 wound around a bobbin 4 is arranged on the inner periphery of the yoke 3. 6 is a fixed iron core, and yoke 3
and the fixed iron core 6 form the excitation of the excitation coil 5.

Reference numeral 7 denotes a cylindrical plunger, which is slidable on the inner circumference of the excitation coil 5 in the axial direction. A hook 7a and a collar 7b are provided at one end of the plunger 7, and a recess 7C is formed at the other end. Reference numeral 8 denotes a shaft made of a magnetic material, and a stepped portion 8a is formed on the outer periphery of the shaft 8, and a movable contact 1 is connected to one end via an insulating member 9.
0 is fixed. Reference numeral 11 denotes a circlip, which is fixed inside the opening of the recess 7C of the plunger 7, and is attached to the shaft 8.
The step portion 8a is restricted from moving in the axial direction by a circlip 11. 13.14 is the 1st. These are second fixed contacts, and are fixed to resin contact covers 15 at positions facing the movable contacts 10, respectively. The first fixed contact 13 is connected to a power source (not shown), and the second fixed contact 14 is connected to the starter motor 1. Further, the contact cover 15 is fixed to the yoke 3 via an insulator 16. 17 is a contact pressure spring;
It is inserted between the recess 7c of the plunger 7 and the shaft 8, and presses the step 8a of the shaft 8 against the circlip 11 side. The contact pressure spring 17 is connected to the movable contact lO and the first. This is a spring pressure for obtaining a predetermined contact pressure between the second fixed contact 13 and 14. A return spring 18 is arranged between the tail 8b of the plunger 8 and the yoke 3, and presses the plunger 8 to the left side.

A housing 19 rotatably holds a drive shirt 20 that transmits the rotation of the starter motor 1 via a bearing. And on the drive shaft 20,
A spline tube 21, an overrunning clutch 22, and a pinion 23 are rotatably held. 24
is the ring gear of the internal combustion engine, and the pinion 23 meshes with it. 25 is a lever made of resin or metal;
One end is engaged with the outer periphery of the spline tube 21, and the other end is engaged with the hook portion 7a of the plunger 7. The lever 25 is fixed by a retainer 26. Further, 27 is a drive spring.

Next, the operation of the above configuration will be explained.

Turn on the starter switch (not shown) and turn on the excitation coil 5.
When the excitation coil 5 is excited, the plunger 7 is attracted by the attraction of the exciting coil 5. Then, the pinion 2
3 toward the ring gear 24, but the drive spring 27 is bent due to the inertial weight of the pinion 23 and overrunning clutch 22.

Then, only the plunger 7 moves, and the shaft 8 is moved between the first and second fixed contacts 13 via the contact pressure spring 17.
．． Try to move it to the 14th side. However, due to the inertial weight of the shaft 8 and the movable contact 10, the contact pressure spring 1
7 will shrink. Then, the contact pressure spring 17 is
The movable contact 10 and the first. A distance greater than the distance that the plunger 7 moves when a predetermined contact pressure with the second fixed contact 13, 14 is obtained and the drive spring 27 is deflected;
A spring pressure is set so that the contact pressure spring 17 contracts with respect to the inertial weight of the shaft 8 and the movable contact lO.

Therefore, the contact pressure spring 17 is compressed, the shaft 8 does not move, and only the plunger 7 moves in the axial direction. Thereafter, the plunger 7 is moved to the pinion 2 via the lever 25.
3 and move it to the ring gear 24 side. At the same time, the plunger 7 moves the shaft 8 via the contact pressure spring 17. Then, when the pinion 23 substantially contacts the ring gear 24, the movable contact 10 moves to the first position. It comes into contact with the second fixed contacts 13 and 14 and rotates the starter motor 1' from a power source (not shown). Further, the rotation of the starter motor 1 is transmitted to the pinion 23 via an overrunning clutch. Then, the ring gear 24 is rotated to start the internal combustion engine.

Therefore, before the pinion 23 comes into contact with the ring gear 24, the movable contact 10 and the first. Since the second fixed contacts 13, 14 are in contact and cannot rotate the pinion 23, good meshing between the pinion 23 and the ring gear 24 can be achieved. Furthermore, since the contact pressure spring 17, which is conventionally required, is used, the number of parts does not increase. Furthermore, when the pinion 23 collides with the ring gear 24, the axial impact is absorbed by the drive spring 27.
can be alleviated. Further, a return spring (for example, disposed between the contact cover 15 and the end of the shaft 9) for returning the shaft 8 (movable contact 10) to its original position can be eliminated.

In addition, as another example, the contact cover 15 and the shaft 8
By installing a return spring between the end of the
It is also possible to eliminate the circlip 11 for regulating the axial movement of the shaft 8.

(Effects of the Invention) As described above, in the present invention, since the contact pressure spring is disposed between the shaft having a movable contact and the plunger, the drive spring is Even if the pinion is delayed in ejecting due to deflection, the contact pressure spring contracts and delays the movement of the movable contact to improve the meshing between the pinion and ring gear, and also to prevent the drive from colliding with the pinion. The spring can absorb shock, and since it uses a contact pressure spring, it has the excellent effect of not increasing the number of parts.

[Brief explanation of drawings]

The figure is a partially sectional front view showing an embodiment of the starter of the present invention. l... Starter motor, 2... Magnet switch, 5... Excitation coil, 7... Plunger, 8...
Shaft, 10... Movable contact, 13, 14. ...First. Second fixed contact, 17... Contact pressure spring, 2
2... Overrunning clutch, 23... Pinion, 24... Ring gear, 25... Lever, 27
...Drive spring.

Claims (1)

[Claims] A starter motor, a pinion to which the rotation of the starter motor is transmitted and meshes with a ring gear of an internal combustion engine, and an excitation coil, which is moved by energization of the excitation coil to move the pinion toward the ring gear. a plunger; a shaft having a movable contact at one end and disposed coaxially with the plunger; a fixed contact for energizing the starter motor when the movable contact of the shaft abuts; and the shaft. and a contact pressure spring disposed between the movable contact and the fixed contact to obtain a predetermined contact pressure between the movable contact and the fixed contact.