JPH0633745B2 - Internal combustion engine starter - Google Patents

Description

TECHNICAL FIELD The present invention relates to a starting device for an internal combustion engine, and more particularly to a starting device having excellent waterproofness and dustproofness.

[Conventional technology]

A starter for an internal combustion engine generally includes a pinion engageable with a ring gear, a one-way clutch arranged between an output shaft of a motor and a pinion, which transmits rotation of the motor to the pinion, a pinion and a clutch. A surrounding housing, and at least the pinion, usually both the pinion and the clutch, is configured as a reciprocating movable member on the output shaft of the motor.

In this starting device, since the end portion of the housing has an opening structure to the internal space of the internal combustion engine, water or dust is generated from the gap between the inner peripheral surface of the housing and the outer peripheral surface of the moving member. There is a problem that it will penetrate inside and shorten the life of the device, and it has been desired to ensure waterproofness and dustproofness.

In order to ensure this waterproofness and dustproofness, the conventional starter has a shaft support member also serving as a bearing between the inner peripheral surface of the housing and the outer peripheral surface of the pinion, as described in Japanese Utility Model Publication No. 61-36778. Was. In addition, the actual development Sho-60-871
As described in No. 42, the drive end of the electromagnetic solenoid, which is one of the internal devices of the starter, is covered with an elastic cover such as a bellows, and the electromagnetic solenoid is protected from water and dust inside. It was

Furthermore, as described in JP-A-62-20673,
There is also an example in which a partition wall having an L-shaped cross section is attached to a position on the inner circumference of the housing facing the outer circumferential surface of the clutch to separate the inside and the outside of the starting device.

[Problems to be solved by the invention]

However, in the method of ensuring waterproofness and dustproofness by the shaft support member described in JP-B-61-36778, it is necessary to polish the outer peripheral surface of the pinion in order to slide the shaft support member on the outer peripheral surface of the pinion. In addition, there is a problem in terms of productivity, such as the need to change the existing production equipment and equipment with the installation of the shaft support member. Further, in this configuration, the gap of the pinion gear molding portion is not sealed, water and dust may enter from there, and there is also a problem that waterproofness and dustproofness are not always sufficient.

Further, instead of covering the driving end portion of the electromagnetic solenoid described in Japanese Utility Model Laid-Open No. 60-87142 with a bellows, the structure for mounting the bellows must be changed, resulting in an increase in the number of parts and a complicated shape. Therefore, there was a problem that productivity deteriorates. There was also a problem with the strength of the bellows and the increase of the space occupied by the bellows.

In the method of providing a partition wall having an L-shaped cross section described in JP-A-62-20673, there is a minute gap between the inner peripheral end surface of the L-shaped portion of the partition wall and the outer peripheral surface of the clutch, and the clutch is used when the engine is started. If the jumps out, the outer peripheral surface of the clutch disengages from the inner peripheral end surface of the L-shaped part of the partition wall, and a large gap may be generated, from which water and dust may enter, and there is a problem that the waterproofness and dustproofness are not always sufficient. It was

As a general method for sealing the gap between the moving members, there is a method using an O-ring or a mechanical seal, but in this case, friction loss increases and energy loss occurs.

An object of the present invention is to provide a starting device for an internal combustion engine which is excellent in waterproofness and dustproofness, excellent in productivity and mass productivity, and provided with a seal mechanism with little energy loss.

[Means for solving problems]

The above-mentioned object is to provide ring-shaped first and second magnetic iron plates and a ring-shaped permanent magnet at a position on the inner peripheral surface of the housing that faces the outer peripheral surface of the clutch. The magnetic iron plates are located inside the starter respectively, and the permanent magnets are installed so as to be located between them. The inner diameters of the first and second magnetic iron plates are larger than the outer diameter of the outer peripheral surface of the clutch and are small between them. A gap is formed, and the inner diameter of the permanent magnet is made larger than the inner diameters of these magnetic iron plates to form a space between the permanent magnet and the first and second magnetic iron plates. The tip of the inner peripheral side of the iron plate is formed as an inclined surface such that the acute angle portion is located on the side of the space, and the tip inclined surface of the first magnetic iron plate and the outer peripheral surface of the clutch are filled with magnetic fluid. On the outer side of the first magnetic iron plate on the surface, The third magnetic iron plate having the same inner diameter as the first magnetic iron plate and an inclined surface in the same direction as the first magnetic iron plate is formed at the tip of the inner peripheral side in contact with the first magnetic iron plate, and the tip of the first magnetic iron plate is attached. A magnetic fluid is allowed to enter a triangular void formed by the inclined surface and the side surface of the third magnetic iron plate, and a sealing mechanism is formed by the first, second and third magnetic iron plates, the permanent magnet and the magnetic fluid. It is achieved by configuring.

[Action]

In the starting device of the present invention configured as described above, the first
The magnetic fluid filled between the tip inclined surface of the magnetic iron plate and the outer peripheral surface of the clutch completely seals the gap without scattering due to the axial movement and rotation of the clutch and the impact applied to the starter, and the friction Excellent waterproof and dustproof properties without loss.

In other words, the sealing mechanism for the internal combustion engine starter has severe operating conditions, and an axial force acts on the seal mechanism every time the clutch moves during engine start-up. May be shocked. In a sealing mechanism using magnetic fluid, it is necessary to prevent the magnetic fluid from scattering even in such a case.

In the present invention, a third magnetic iron plate having the same shape as the first magnetic iron plate is attached to the outside of the first magnetic iron plate, and is formed by the tip inclined surface of the first magnetic iron plate and the side surface of the third magnetic iron plate. The magnetic fluid is allowed to enter the triangular voids. As a result, the magnetic fluid is firmly held by the third magnetic iron plate and does not scatter to the outside even when the clutch outer peripheral surface moves outward in the axial direction when the engine is started or when the starter is impacted by vibration or the like. It is highly reliable and has excellent waterproof and dustproof properties.

Furthermore, since the seal mechanism of the present invention has a simple structure using a magnetic iron plate, a magnet, and a magnetic fluid, it can be incorporated with a small number of parts without significantly changing the configuration of the current product, resulting in excellent productivity. Is secured.

The present invention also considers the mass productivity of the starting device. That is, when the magnetic fluid is filled in the seal portion, it is injected from the pinion side outside the starter after the starter is assembled. At this time, according to the present invention, the first
Since the magnetic fluid is filled between the magnetic iron plate and the outer peripheral surface of the clutch, it is easy to access when injecting the magnetic fluid, and the filling state of the injected magnetic fluid can be visually checked from the outside to check the extra sealability separately. Is unnecessary. Further, at the time of injecting the magnetic fluid, the third magnetic iron plate is further outside and the tip inclined surface is directed outward, so that the inclined surface is used as a guide to move the injection nozzle in the circumferential direction to inject the magnetic fluid. Therefore, the filling work of the magnetic fluid becomes easy.

〔Example〕

 Preferred embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1 showing the overall configuration of a starting device for an internal combustion engine,
Reference numeral 1 is a housing of the starting device, and this housing 1 is an aluminum die casting type product. Mounted on the housing 1 is a motor casing 4 composed of an rotatably supported armature 2 and a field coil 3 installed in the radial direction of the armature 2. Output shaft 5 of armature 2
A pinion 6 is located above, and the output shaft 5 and the pinion 6 are connected via a one-way clutch 7. Due to this clutch 7, the pinion 6 rotates in the drive direction together with the output shaft 5, while rotating in the opposite drive direction relative to the output shaft 5. Further, the pinion 6 and the clutch 7 are configured as moving members that can reciprocate on the output shaft in the axial direction. The housing 1 surrounds the pinion 6 and the clutch 7.

An electromagnetic solenoid 8 is also mounted on the housing 1, and the shift lever 9 is activated by the activation of the electromagnetic solenoid 8.
The pinion 6 is reciprocated together with the clutch 7 via. When the pinion 6 is pushed by the shift lever 9 to move, the pinion 6 engages with a ring gear of an internal combustion engine (not shown).

The outer peripheral portion of the clutch 6 is made of a magnetic material, and a seal mechanism 30 is arranged in the gap 10 between the inner peripheral surface of the housing 1 and the outer peripheral surface of the clutch 6.

As can be seen from FIG. 2, the sealing mechanism 30 has ring-shaped permanent magnets 12 fixed to the inner peripheral surface of the housing 1 facing the outer peripheral surface of the clutch 7. Two ring-shaped magnetic iron plates 13 and 31 and one magnetic iron plate 32 fixed to the inner peripheral surface of 1.
Are arranged in contact with the magnet 12. That is, the magnetic iron plate 13 is located outside the starting device, the magnetic iron plate 32 is located inside the starting device, and the magnet 12 is located between them. The inner diameters of the magnetic iron plates 13 and 32 are set to be larger than the outer diameter of the outer peripheral surface of the clutch to form a minute gap therebetween, and the inner diameter of the magnet 12 is set to be larger than the inner diameters of the magnetic iron plates 13 and 32 so that the magnet 12 and the magnetic iron plate are A space 15 is formed between the side walls 13 and 32. The tip of the outer magnetic iron plate 13 on the inner peripheral side is formed as an inclined surface so that the acute angle portion 17 is located on the space 15 side, and the magnetic fluid 20 is filled between the tip inclined surface of the magnetic iron plate 13 and the outer peripheral surface of the clutch. Has been done.

Further, the magnetic iron plate 31 is provided outside the magnetic iron plate 13 with the first
The magnetic iron plate 31 is located in contact with the magnetic iron plate 1 of
A slanted surface having the same inner diameter as that of No. 3 and having the same direction as the inner circumferential end is formed, and the magnetic fluid 2 is allowed to enter the triangular void formed by the slanted end of the magnetic iron plate 13 and the side surface of the magnetic iron plate 31. . As a result, the magnetic fluid 20 is transferred to the magnetic iron plates 13 and 3.
1, 32 and the magnetic circuit formed between the magnet 12 and the clutch 7, and magnetically held by the magnetic iron plate 31.

The magnetic iron plate 32 is made thicker than the magnetic iron plate 13 in order to firmly fix the magnet 12 by press fitting, and has an end surface 18 parallel to the outer peripheral surface of the clutch. The magnetic iron plate 32 side is not filled with magnetic fluid.

The magnetic fluids 20 and 21 used have a specific gravity of 1.02 to
1.31, viscosity 50-120 cps / 30 ° C, magnetizing force 20
It has a physical property value of 0 to 500 Gauss.

By configuring the seal mechanism 30 in this manner, the magnetic fluid 20 as the seal material is held without scattering even when the clutch 7 reciprocates, rotates, or an impact is applied to the starter, and the magnetic fluid 20 and the outer peripheral surface of the clutch 7 are retained. Completely prevent water, oil and dust from passing through the gap between the inner peripheral surface of the housing 1 and entering the inside of the starting device, and exhibiting excellent waterproofness and dustproofness without causing friction loss. You can

That is, in the present embodiment, not only is the magnetic fluid 20 simply filled between the tip inclined surface of the magnetic iron plate 13 and the outer peripheral surface of the clutch, but the magnetic iron plate 31 having the same shape as the magnetic iron plate 13 is provided further outside the magnetic iron plate 13. Is attached to allow the magnetic fluid to enter the triangular void formed by the inclined surface of the tip of the magnetic iron plate and the side surface of the third magnetic iron plate. As a result, the magnetic fluid 20 is held by the magnetic iron plate 31 and does not scatter to the outside even when the outer peripheral surface of the clutch moves outward in the axial direction when the engine is started or when the starter is impacted by vibration or the like. It is highly resistant and exhibits excellent waterproof and dustproof properties.

In addition, the seal mechanism 30 of the present embodiment includes the magnetic iron plates 13 and 3
Since it has a simple structure using the magnets 1, 32, the magnets 12 and the magnetic fluid 20, it can be incorporated with a small number of parts without largely changing the configuration of the current product, and high productivity can be secured.

Further, the sealing mechanism 30 of the present embodiment also considers the mass productivity of the starting device. That is, the magnetism that fills the seal with the magnetic fluid 320 is injected from the pinion side outside the starter after the starter is assembled. At this time, in this embodiment, since the magnetic fluid 20 is filled between the magnetic iron plate 13 located outside the starter and the outer peripheral surface of the clutch, access is easy at the time of injecting the magnetic fluid, and the filling of the injecting magnetic fluid 30 is performed. The condition can be visually checked from the outside, and it is not necessary to perform an extra confirmation work of sealing property. Further, when the magnetic fluid is injected, since the magnetic iron plate 31 is further outside and the tip inclined surface faces the outside, the injection nozzle is moved in the circumferential direction using the inclined surface as a guide to inject the magnetic fluid 20. And the filling work of the magnetic fluid becomes easy. As described above, the starting device of this embodiment is excellent in waterproofness, dustproofness, and mass productivity.

A drainage passage 22 is provided in a portion of the housing 1 adjacent to the pinion 6. As a result, the water lifted up by the ring gear of the internal combustion engine is sealed by the seal mechanism 11, and the water flowing into the housing 1 adjacent to the pinion 6 is promptly discharged from the backwater passage 22. Can be prevented more effectively.

As described above, according to the internal combustion engine starter of the present invention, the magnetic fluid is retained without scattering even when the clutch reciprocates and rotates and the starter receives an impact.
It exhibits excellent waterproofness and dustproofness, and can extend the life of the starting device. Further, it is not necessary to change the structure of the existing product significantly, and the productivity is excellent, and the magnetic fluid can be easily filled, which is excellent in mass productivity, and further, there is no friction loss and energy loss can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an essential part of a starting device for an internal combustion engine according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a sealing mechanism of the starting device. Explanation of reference numerals 1 ... Housing 5 ... Output shaft 6 ... Pinion 7 ... Clutch 10 ... Gap 12 ... Magnet 13 ... (First) magnetic iron plate 20 ... Magnetic fluid 30 ... Sealing mechanism 31 ... … (Third) magnetic iron plate 32 …… (Second) magnetic iron plate

Claims (2)

[Claims] 1. A pinion engageable with a ring gear, a one-way clutch disposed between an output shaft of a motor and a pinion for transmitting the rotation of the motor to the pinion, and a housing surrounding the pinion and the clutch. In a starting device for an internal combustion engine, wherein the pinion and the clutch are configured as a movable member capable of reciprocating on an output shaft of a motor, a ring-shaped first and second magnetic member is provided at a position facing an outer peripheral surface of the clutch on an inner peripheral surface of the housing. The iron plate and the ring-shaped permanent magnet are attached such that the first magnetic iron plate is located outside the starting device and the second magnetic iron plate is located inside the starting device, and the permanent magnet is located between them. The inner diameter of the second magnetic iron plate is made larger than the outer diameter of the clutch outer peripheral surface to form a minute gap between them, and the inner diameter of the permanent magnet is made larger than the inner diameter of these magnetic iron plates to make it permanent. A space is formed between the magnet and the first and second magnetic iron plates, and the tip of the inner peripheral side of the first magnetic iron plate located outside the starting device is formed as an inclined surface so that the acute angle portion is located on the space side. Formed, filling the magnetic fluid between the tip inclined surface of the first magnetic iron plate and the outer peripheral surface of the clutch, and further contacting the first magnetic iron plate on the outer peripheral surface of the first magnetic iron plate on the inner peripheral surface of the housing. Then, a third magnetic iron plate having the same inner diameter as the first magnetic iron plate and an inclined surface in the same direction as that of the first magnetic iron plate is formed at the tip on the inner peripheral side, and the tip inclined surface of the first magnetic iron plate and the third magnetic iron plate are attached. The magnetic fluid is allowed to enter into a triangular void formed by the side surface of the magnetic iron plate and the sealing mechanism is configured by the first, second and third magnetic iron plates, the permanent magnet and the magnetic fluid. An internal combustion engine starting device. 2. A starting device for an internal combustion engine according to claim 1, wherein a drainage passage is provided in a portion of the housing adjacent to the pinion.