JP2002181082A - Power transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a power transmission for a vehicle. SOLUTION: This transmission is characterized by comprising a one-way clutch in which a boss 3 and a clutch outer 5 arranged with space in a radial direction around the boss 3 are connected with each other via a rolling element 4 held between the boss 3 and the clutch outer 5, integrally constituting the clutch outer 5 and a power transmission member driven by rotation of a starter and mounting the boss 3 on a crankshaft 1 so as not to be rotatable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission device for a vehicle, and more particularly, to a device for transmitting the rotational power of a starter to a crankshaft via a one-way clutch.

[0002]

2. Description of the Related Art FIG. 3 is a cross-sectional view (a cross-sectional view taken along the line III-III of FIG. 4) showing an example of a conventional power transmission device for a vehicle, and FIG. .

In these figures, a boss 03 is rotatably mounted around a crankshaft 01 of an internal combustion engine via a bush 02. A driven gear 01 is attached to an end of the boss 03.
7 are welded together. The driven gear 017 meshes with the drive gear 018, and rotational power of a starter (not shown) is transmitted.

[0004] A clutch outer 05 is disposed around the boss 03 with a gap in the radial direction. The two members 03 and 05 are connected to each other via a columnar rolling element 04 held in a space 08 formed in the clutch outer 05 to form a one-way clutch.

The one-way clutch portion will be described in detail. A cam surface 05a is formed at the deepest portion of the space 08, that is, at the inner peripheral surface of the clutch outer 05 where the rolling element 04 contacts.
A spring holder hole 012 is formed from the outer periphery of the clutch outer 05 to the inside of the space 08, and a spring stopper 013 is press-fitted into the spring holder hole 012. And its spring stopper 013 and rolling element 0
4, the spring 010 and the spring holder 011 are fitted, and the rolling element 04 is urged in the counterclockwise direction in FIG. Reference numeral 014 is a cover made of sheet metal.

A flange 020 fixed to a magnet rotor 022 of the generator with rivets 021 is attached to the clutch outer 05 by bolts 019. The center boss of the flange 020 is connected to the crankshaft 01.
Is fixed so that it cannot rotate.

In such a vehicle power transmission device,
The drive gear 018 is rotated by a starter (not shown), and the driven gear 01 meshed with the drive gear 018.
7, and boss 03 welded to this driven gear 017
When the roller rotates in the direction of the arrow P (counterclockwise) in FIG. 3, the rolling element 04 is also urged by the spring 010 and moves counterclockwise. Then, the rolling element 04 is pressed tightly against the boss 03 and the clutch outer 05 in a wedge-shaped space formed between the outer peripheral surface of the boss 03 and the cam surface 05a of the clutch outer 05. It is transmitted to the clutch outer 05 as it is. The rotation of the clutch outer 05 is further transmitted to the crankshaft 01 and the magnet rotor 022 of the generator via the flange 020.

On the other hand, when the boss 03 rotates in the direction of the arrow Q (clockwise) in FIG. 3, the rolling element 04 moves clockwise against the force of the spring 010. Then the rolling element 04 becomes the boss
Neither the outer peripheral surface of 03 nor the cam surface 05a of the clutch outer 05 comes into close contact, and the rotation of the boss 03 is not transmitted to the clutch outer 05. The same applies to the case where the crankshaft 01 and thus the clutch outer 05 rotate relatively counterclockwise with respect to the boss 03.

[0009]

In the conventional vehicle power transmission device, the magnet rotor 022 of the generator is attached to the clutch outer 05 of the one-way clutch via the dedicated flange 020, so that the number of parts is large. , The dimensions in the axial direction are widened, and the layout restrictions are great. In addition, since the driven gear 017 is fixed to the boss 03, the axial dimension is further increased.

Also, a clutch outer of a one-way clutch is provided.
The cam surface 05a of the 05 is required to have strength and hardness, but a material that satisfies them is expensive and difficult to work. Furthermore, since the spring holder hole 012 can be drilled only from the outer peripheral side of the clutch outer 05, it is necessary to press-fit the spring stopper 013 to stop the spring 010,
It was troublesome.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, an invention according to claim 1 is characterized in that a boss and a clutch outer that is radially spaced around the boss. A one-way clutch in which the boss and the clutch outer are connected to each other via the held rolling element, and the clutch outer and a power transmission member driven by rotation of a starter are integrally formed, The boss is non-rotatably mounted on the crankshaft.

According to the first aspect of the present invention, since the power transmission member driven by the rotation of the starter is integrally formed with the clutch outer, the dimension in the axial direction is significantly reduced. Further, since the boss is non-rotatably mounted on the crankshaft, the number of parts is small, and the layout of the generator is free.

Next, according to a second aspect of the present invention, in the first aspect of the invention, the clutch outer comprises a retainer on the shaft center side and an outer body in contact with the outer periphery of the retainer. And a space for accommodating the rolling element is formed in the retainer at a position corresponding to the cam surface.

According to a second aspect of the present invention, the clutch outer of the one-way clutch comprises a retainer on the shaft center side and an outer body in contact with the outer periphery of the retainer. The cam surface is formed in a part of the retainer, and the retainer has a space for accommodating the rolling element at a position corresponding to the cam surface, so that only the outer body on which the cam surface is formed has strength and hardness. For the retainer, which is made of an expensive material with a large size and only needs to play the role of housing and holding the rolling element, use a material that is inexpensive and easy to process, and simplify the design to save costs. At the same time, the weight can be reduced. Further, since the main part of the processing of the outer body is only the shallow cam surface, the processing cost is further reduced.

According to the second aspect of the present invention, the bottom of the spring holder hole into which the spring for biasing the rolling element is inserted can be formed on the inner peripheral surface of the outer body. Can be eliminated from the outside to press-fit a separate spring stopper.

According to a third aspect of the present invention, in the second aspect of the present invention, the retainer is divided into two parts by a plane intersecting the rotation axis, and the divided plane is provided with a space for accommodating the rolling element and the rolling element. A spring holder hole 12 for a spring for biasing the moving body is formed. Therefore, according to the third aspect of the invention, it becomes easier to machine the space for accommodating the rolling element and the spring holder hole of the spring for biasing the rolling element.

[0017] In addition, the invention according to claim 4 provides the invention according to claim 3.
In the invention described above, the outer peripheral surface of the retainer is formed in a truncated cone shape whose diameter gradually increases from the divided surface toward both end surfaces, and the inner peripheral surface of the outer body has two correspondingly. It is characterized by forming a truncated cone surface. Therefore, according to the fourth aspect of the invention, when assembling the clutch outer, if one of the divided retainers is overlapped with the other of the outer body and the other of the retainer, positioning can be performed very easily.

[0018]

1 is a partially cutaway side view showing an embodiment of the present invention (a view taken along the line II of FIG. 2), and FIG.
2 is a sectional view taken along the line II-II, showing a state in which a rolling element 4, a spring 10, and a spring holder 11 in FIG. 1 are removed.

In these figures, a boss 3 is non-rotatably attached to a crankshaft 1 of an internal combustion engine by a key 2. A clutch outer 5 is arranged around the boss 3 with a gap in the radial direction. The boss 3 and the clutch outer 5 are connected to each other via a cylindrical rolling element 4 held between the boss 3 and the clutch outer 5 to form a one-way clutch.

The clutch outer 5 comprises a retainer 6 on the shaft center side and an outer body 7 in contact with the outer periphery of the retainer 6. A cam surface 7a is formed on a part of the inner periphery of the outer body 7. On the other hand, a space 8 for accommodating the rolling element 4 is formed in the retainer 6 at a position corresponding to the cam surface 7a.

In the present embodiment, the retainer 6 is divided into a left retainer 6a and a right retainer 6b by a plane 6c orthogonal to the rotation axis 9, and connected by screws 15. A space 8 for accommodating the rolling element 4 and a spring holder hole 12 are formed along the dividing surface 6c. Further, the spring 10 is inserted into the spring holder hole 12.
And the spring holder 11 are inserted to urge the rolling element 4 in the counterclockwise direction in FIG.

In this embodiment, the left retainer 6
a, The outer peripheral surface 6d of the right retainer 6b is formed in a truncated cone shape whose diameter gradually increases from the dividing surface 6c toward both end surfaces. And, correspondingly, the inner peripheral surface of the outer body 7 forms two truncated conical surfaces.

Further, in the present embodiment, the outer body 7
A driven gear 7b is formed on the outer periphery of the drive gear 18 and meshes with a drive gear 18 which is driven to rotate by a starter (not shown).

In such a vehicle power transmission device,
The drive gear 18 is rotated by a starter (not shown), and when the driven gear 7b meshing with the drive gear 18 rotates in the direction of the arrow R (clockwise) in FIG.
Is urged in the counterclockwise direction by the spring 10 so that its movement is hindered, and is a wedge-shaped space formed between the outer peripheral surface of the boss 3 and the cam surface 7a of the outer body 7. 7 is pressed tightly. Thus, the rotation of the outer body 7 is transmitted to the boss 3 as it is, and the crankshaft 1 rotates.

On the other hand, when the outer body 7 rotates in the direction of the arrow S (counterclockwise) in FIG. 1, the rolling elements 4 are brought into contact with both the outer peripheral surface of the boss 3 and the cam surface 7a of the outer body 7.
The rotation of the outer body 7 is not transmitted to the boss 3 and the crankshaft 1 in a close contact. Outer body 7
The same applies to the case where the crankshaft 1 and therefore the boss 3 rotate relatively clockwise.

Thus, the clockwise rotation of the clutch outer 5 by the starter is transmitted to the crankshaft 1, but the clockwise rotation of the crankshaft 1 after the engine is started is not transmitted to the clutch outer 5.

In this embodiment, the driven gear 7b
Are formed integrally with the outer body 7 instead of the boss 3, so that the dimension in the axial direction is much smaller than that of the conventional one. Further, since the boss 3 is directly mounted on the crankshaft 1 so as not to rotate and there is no flange 020 as in the conventional case, the number of parts is small, and the layout of the generator is free.

In this embodiment, the clutch outer 5
Are divided into a retainer 6 in which a space 8 for accommodating the rolling element 4 is formed and an outer body 7 in contact with the outer periphery of the retainer 6 and having a cam surface 7a formed in a part of the inner periphery. In addition to manufacturing only the outer body 7 that requires strength and hardness from a strong material,
For the retainer 6 having only the role of holding, an inexpensive and easy-to-process material such as plastic can be used. Therefore, not only the cost can be reduced, but also the weight can be reduced.

Since the spring holder hole 12 is formed in the retainer 6 and the bottom of the spring holder hole 12 is formed on the inner peripheral surface of the outer body 7, the spring holder hole 012 is formed from the outside as in the conventional case. The step of piercing and press-fitting the spring stopper 013 becomes unnecessary. The main part of the processing of the outer body 7 made of a strong material is only the cam surface 7a, and the space 8 is formed in the retainer 6 which can use a material which can be easily processed. The processing cost is significantly reduced as compared with the case where the space 08 is deeply cut.

In the original embodiment, the retainer 6 is divided into two parts by a plane 6c perpendicular to the rotation axis 9, and the space 8 accommodating the rolling element 4 and the spring 1 are formed along the division surface 6c.
0, since the spring holder hole 12 for inserting the spring holder 11 is formed, the processing is also easy at that point.

In addition, in the present embodiment, each of the outer peripheral surfaces 6d of the divided retainers 6a, 6b is formed in a truncated conical shape whose diameter gradually increases from the divided surface 6c toward both end surfaces.
Correspondingly, the inner peripheral surface of the outer body 7 forms two frusto-conical surfaces, so when assembling the outer body 7, one of the divided retainers 6a and 6b, the other of the outer body 7 and the other of the retainers, is used. Positioning can be performed very easily if they are sequentially stacked.

In this embodiment, the driven gear 7b is used as a power transmission member driven by the rotation of the starter. However, this is not necessarily a gear. For example, a combination of a sprocket and a chain, a pulley and Various types can be used depending on the case, such as combination with a belt. Although the driven gear 7b is formed integrally with the outer body 7, the outer body 7 and the driven gear 7b may be formed separately and then fixed to each other to be integrally formed.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing a preferred embodiment of the present invention (a view taken in the direction of an arrow II in FIG. 2).

FIG. 2 is a sectional view taken along the line II-II of FIG.

FIG. 3 is a cross-sectional view (a cross-sectional view taken along line III-III in FIG. 4) showing an example of a conventional vehicle power transmission device.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Crank shaft, 2 ... Key, 3 ... Boss, 4 ... Rolling element, 5
... clutch outer, 6 ... retainer, 6a ... left retainer, 6b ... right retainer, 6c ... dividing surface, 6d ... outer peripheral surface,
7: outer body, 7a: cam surface, 7b: driven gear, 8: space, 9: rotation axis, 10: spring, 11: spring holder, 12: spring holder hole, 15: screw, 18: drive gear.

Claims (4)

[Claims] 1. The boss and the clutch outer are connected to each other via a rolling element held between the boss and a clutch outer disposed at a radial distance from the boss and surrounding the boss. A power transmission device comprising a direction clutch, wherein the clutch outer and a power transmission member driven by rotation of a starter are integrally formed, and the boss is non-rotatably mounted on a crankshaft. . 2. The clutch outer comprises a retainer on the shaft center side and an outer body in contact with an outer periphery of the retainer. The outer body has a cam surface formed on a part of an inner periphery thereof. The power transmission device for a vehicle according to claim 1, wherein a space for accommodating the rolling element is formed at a position corresponding to the cam surface. 3. The retainer is divided into two parts by a surface intersecting a rotation axis, and a space for accommodating the rolling element and a spring holder hole of a spring for biasing the rolling element are formed on the divided surface. The vehicle power transmission device according to claim 2, wherein: 4. An outer peripheral surface of the retainer is formed in a truncated cone shape whose diameter gradually increases from the divided surface toward both side end surfaces, and the inner peripheral surface of the outer body has two correspondingly. The power transmission device for a vehicle according to claim 3, wherein a frustoconical surface is formed.