JPH10281261A - Pulley - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the generation of noise due to the fluctuation of rotation of an input shaft, in a pulley incorporating a one-way clutch. SOLUTION: A pulley A comprises a drive annular body 1 fixed on an input shaft B; a driven annular body 2 which is disposed on the outer periphery of the drive annular body 1' and around which a belt C is wound; and a one-way clutch 3 located between the drive annular body 1 and the drive annular body 2. In one-way clutch 3, a torque value per roller 1 to press a roller 13 against the lock side is set to a range of 0.3-12 [N/m] This constitution performs smooth rolling of the roller 13 without jolting even when the input shaft B is rotationally fluctuated when the roller 13 of the one-way clutch 3 is rolled especially from a free position to a lock position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a pulley having a one-way clutch. This pulley may be, for example, a pulley mounted on an outer end of a crankshaft of an engine of an automobile or the like.

[0002]

2. Description of the Related Art In general, it is known that a crankshaft is advanced or delayed due to uneven explosion of a combustion chamber, and its rotational speed is liable to fluctuate particularly in an idling rotation range (for example, around 800 rpm).

On the other hand, for example, Japanese Utility Model Application No. 58-489.
As shown in the microfilm of No. 68 (No. 59-155346), a one-way clutch is provided on an auxiliary drive pulley attached to the crankshaft, and the one-way clutch is in a free state as the crankshaft rotates. And a lock state, so as to attenuate the transmission of rotational fluctuations from the crankshaft to the pulley. This one-way clutch has a general configuration using rollers.

[0004]

By the way, in the above conventional example, when the load of the spring of the one-way clutch is set low, the rollers move from the free position to the locked position in a situation where the rotation of the crankshaft fluctuates. When rolling, the rollers may fluctuate without rolling smoothly due to the effect of the rotation fluctuation, which may cause a so-called knocking noise.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to suppress generation of abnormal noise due to rotation fluctuation of an input shaft in a pulley incorporating a one-way clutch.

[0006]

A first pulley according to the present invention comprises a driving ring fixed to an input shaft, a driven ring disposed around the driving ring and around which a belt is wound, and a driving pulley. The one-way clutch includes a one-way clutch interposed between the ring body and the driven ring body, and the torque value applied to each roller for pressing the rollers toward the lock side in the one-way clutch is 0.1%.
It is set in the range of 3 to 12 [N · m].

The second pulley of the present invention includes a driving ring fixed to the input shaft, a driven ring disposed around the driving ring and around which a belt is wound, a driving ring and a driven ring. A one-way clutch interposed between the cage and the one-way clutch. The one-way clutch includes a plurality of rollers, a retainer having a pocket for accommodating the plurality of rollers, and an outer ring disposed on an outer periphery of the retainer. A one-way clutch including a member, an inner ring member provided with a wedge-shaped space forming cam surface at a position corresponding to a pocket of the retainer, and an elastic member for pressing a roller toward a narrow side of the wedge-shaped space. The torque value obtained by multiplying the elasticity per elastic member by the radius from the axis of the member to the elastic member is set in the range of 0.3 to 12 [N · m].

The one-way clutch provided on the pulley switches between a locked state and a free state in accordance with the rotation fluctuation of the input shaft, and transmits or interrupts power from the driving ring to the driven ring, thereby cutting off. Although the pulsation of the driven ring is attenuated, the rollers roll smoothly without fluttering, particularly when the rollers roll from the free position to the locked position.

In addition, in the second pulley, in addition to the above operation, the cam surface of the one-way clutch is provided on the inner ring member side instead of the outer ring member side. It can be prevented from coming off.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the embodiments shown in FIGS.

1 to 5 relate to an embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a pulley, and FIG. 2 is a sectional view taken along line (2)-(2) of FIG. Diagram,
FIG. 3 is a developed plan view showing a part of the one-way clutch, and FIG.
Is a chart showing fluctuations in the number of revolutions of the pulley, and FIG. 5 is a chart showing noise characteristics of the pulley.

The illustrated pulley A includes a drive ring 1 fixed to the shaft end of a crankshaft B of an automobile engine as an input shaft, and a driven ring 2 around which a belt C is wound.
And a one-way clutch 3 interposed between the driving ring 1 and the driven ring 2. A damper mass 4 is provided on the outer periphery of the driving ring 1 to attenuate phenomena such as torsion and bending resonance occurring in the crankshaft B, particularly in a high-speed rotation region. The damper mass 4 is configured such that an elastic body 7 such as rubber is baked and bonded between a radially outward flange 5 of the drive ring 1 and a metal annular plate 6.

The driven ring 2 is made of a metal plate whose upper half section is formed in a substantially U-shape.

The one-way clutch 3 includes an inner race 10 having a flat key-shaped cam surface 10a at several locations on the outer peripheral surface.
An outer ring 11 which is fitted concentrically to the inner ring 10;
A retainer 12 having pockets 12a formed radially inward and outward corresponding to the cam surface 10a, and a plurality of rollers 13 accommodated one by one in each pocket 12a of the retainer 12.
Recess 1 connected to each pocket 12a in cage 12
A coil spring 14 as an elastic member that presses the rollers 13 toward the lock side (a narrow side of the wedge-shaped space between the cam surface 10a and the inner peripheral surface of the outer ring 11), and one end of the coil spring 14; And a spring receiving member 15 which is engaged and abuts on the peripheral surface of the roller 13. Coil spring 14
The roller 13 is disposed at a position offset toward the inner ring 10, that is, on the inner diameter side, in order to impart the resilient biasing force to the roller 13 in a manner that assists the rotation of the roller 13 in a well-balanced and efficient manner. At the center in the axial direction.

In order to seal the one-way clutch 3, the bushes 20, 21, the cover 22, and the seal 2
3, 24 are provided. First, bushes 20, 21
Are disposed on both sides of the retainer 12 between the inner and outer races 10 and 11 of the one-way clutch 3, and the cover 22 is provided on the drive ring 1 so as to conceal and protect the one-way clutch 3 from being exposed to the outside. Attached to the outer end face, seals 23 and 2
Reference numeral 4 is baked and adhered to both outer peripheral shoulders of the driven ring body 2.

The pulley A described above can absorb rotation fluctuation of the crankshaft B by the one-way clutch 3. I mean. Normally, the rotation speed of the crankshaft B fluctuates in a sine curve shape shown by a broken line in FIG.
The one-way clutch 3 is switched between a locked state and a free state in accordance with the rotation fluctuation of
Causes synchronous rotation with the driving ring 1 or rotation due to the rotational inertia of the driven ring 2 itself, thereby suppressing rotation fluctuation of the driven ring 2 as shown by a solid line in FIG.

In short, when the rotational speed of the crankshaft B and the driving ring 1 is relatively faster than that of the driven ring 2, the rollers 13 of the one-way clutch 3 are rolled to the narrow side of the wedge-shaped space and locked. Drive ring 1
And the driven ring 2 are rotated integrally. However, when the rotation speed of the crankshaft B and the driving ring 1 is relatively lower than that of the driven ring 2 of the one-way clutch 3, the rollers 13 of the one-way clutch 3 roll to the wide side of the wedge-shaped space. The driving ring 1
, The transmission of the rotational power to the driven ring 2 is interrupted, and the driven ring 2 rotates only by the rotational inertia force. By such an operation, the rotation fluctuation of the driven ring 2 can be suppressed.

Here, in the present invention, in the one-way clutch 3, the torque applied to each roller for pressing the roller 13 to the lock side is set in the range of 0.3 to 12 [Nm]. doing. This torque value is determined by the radius r from the axis O of the drive ring 1 to the coil spring 14 and the coil spring 14
Is multiplied by the spring force p per one. Thus, in the operation of the one-way clutch 3 described above, the rollers 13 smoothly roll without fluttering, particularly when the rollers 13 roll from the free position to the lock position. In addition,
In the present embodiment, since the cam surface 10a of the one-way clutch 3 is provided not on the outer ring 11 side but on the inner ring 10 side, it is possible to prevent the rollers 13 from coming off the lock position due to centrifugal force even in a high-speed rotation range. The operation of the rollers 13 is stabilized in combination with the above-described fluttering suppression.

Incidentally, the noise characteristics of the pulley A are examined, and will be described. FIG. 5 is a chart showing the noise characteristics of the pulleys. The measurement conditions are pulley size φ154 mm, rotation speed 800 rpm, and full load.

In FIG. 5A, the torque value is set to 0.2 [N ·
m], the data for the case where
It can be seen that the sound pressure is extremely high at a specific frequency 93 [Hz], and that the rattling of the rollers 13 is generated.

On the other hand, in FIG.
[N · m] or more is shown for the case where it is set to not less than [N · m].
It can be seen that flutter is suppressed and no abnormal noise is generated.

If the torque value of the one-way clutch 3 is less than 0.3 [N · m], the crankshaft B
As a result, the rattling noise of the rollers 13 is generated due to the rotation fluctuation. On the other hand, if the torque value exceeds 12 [N · m], it becomes difficult for the roller 13 to roll from the lock side to the free side, and the original function of the one-way clutch 3 is impaired. Based on these findings, the appropriate range of the torque value is specified as described above.

It should be noted that the present invention is not limited to only the above embodiment, and various applications and modifications are conceivable.

(1) In the above embodiment, the coil spring 14 is taken as an example of the elastic member of the one-way clutch 3, but various types of leaf springs and elastic pieces can be used instead.

(2) In the above embodiment, an example is described in which the cam surface 10a of the one-way clutch 3 is formed on the inner ring member side. However, the present invention can be applied to the one provided on the outer ring member side.

[0026]

According to the first aspect of the present invention, the one-way clutch operates so as to suppress the rotation fluctuation of the input shaft. Especially when the rollers roll from the free position to the lock position, the rollers do not flutter. It can be rolled smoothly.

According to the second aspect of the invention, in addition to the effect of the first aspect, since the cam surface of the one-way clutch is provided on the inner ring member side instead of the outer ring member side, the rollers are rolled by centrifugal force even in a high speed rotation range. It is possible to prevent the lock position from deviating. Therefore, the synergistic effect of this effect and the effect of specifying the torque value makes it possible to enhance the operation stability of the rollers.

As described above, according to the present invention, the operation of the one-way clutch can be stabilized, and the effect of suppressing the rotation fluctuation of the pulley can be enhanced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a pulley according to an embodiment of the present invention.

FIG. 2 is a diagram showing only a one-way clutch in a cross section taken along line (2)-(2) of FIG. 1;

FIG. 3 is a developed plan view showing a part of the one-way clutch.

FIG. 4 is a chart showing fluctuations in the number of revolutions of a pulley.

FIG. 5 is a table showing noise characteristics of pulleys.

[Explanation of symbols]

 Reference Signs List A pulley B crankshaft C belt 1 drive ring 2 driven ring 3 one-way clutch 10a cam surface 13 roller 14 coil spring

Claims (2)

[Claims] 1. A drive ring fixed to an input shaft, a driven ring disposed around the drive ring and around which a belt is wound, and interposed between the drive ring and the driven ring. And a torque value applied to each roller for pressing the roller toward the lock side in the one-way clutch is 0.3 to 12%.
A pulley set in the range of [N · m]. 2. A drive ring fixed to the input shaft, a driven ring disposed around the drive ring and around which a belt is wound, and interposed between the drive ring and the driven ring. A one-way clutch comprising: a plurality of rollers; a cage having a plurality of pockets for accommodating the plurality of rollers; an outer ring member provided on an outer periphery of the cage; and a cage. An inner ring member provided with a cam surface for forming a wedge-shaped space at a position corresponding to the pocket, and an elastic member for pressing the rollers toward the narrow side of the wedge-shaped space. A pulley, wherein a torque value obtained by multiplying a radius up to the elastic member by an elastic force per elastic member is set in a range of 0.3 to 12 [N · m].