KR100395362B1 - Pulley unit - Google Patents

Abstract

A belt drive pulley unit for transmitting the rotation of the crankshaft of the engine fluctuating within a narrow range of the angular velocity to the rotational shaft of the engine aid, wherein the pulley unit is mounted around the rotational shaft of the engine aid and is oriented in one direction by the crankshaft through the belt. A pulley which is rotated by a pulley, an inner member provided in the pulley and mounted on the rotating shaft to rotate with the rotating shaft, a radial load acting on the pulley, and a cloud mounted between the pulley and the inner member to support a moment load. To transmit the rotation of the pulley to the rotary shaft when the angular speed of the pulley exceeds the angular velocity of the rotary shaft of the engine aid during one rotation of the contact bearing and the crankshaft, and the rotary shaft rotates at a larger angle than the pulley To block the rotation of the pulley on the axis of rotation Is mounted between the pulley and the inner member consists of a one-way clutch with the engaging element.

Description

Pulley Unit {PULLEY UNIT}

The present invention relates to a pulley unit mounted on a rotating shaft of an engine auxiliary such as an alternator driven by an engine.

Most internal combustion engines generate driving energy during an explosion stroke. No other driving energy is generated during the other stroke. The angular speed of the crankshaft changes during one revolution.

Therefore, in most internal combustion engines, the crankshaft is equipped with a flywheel for smooth rotation by increasing the inertia of the crankshaft. Since the resistance to torsional stress is limited, it is impossible to infinitely increase the inertia of the crankshaft.

Therefore, it is impossible to completely eliminate the fluctuation in the angular velocity.

Diesel engines have a large angular velocity fluctuation, especially compared to gasoline engines.

The crankshaft of many diesel engines in the low speed range varies by more than ± 20%.

An engine aid, such as an alternator, is driven from this crankshaft through a belt at a constant speed. Since these braces have large moments of inertia, slip and slip noise tend to occur between pulleys and belts mounted on the rotating shaft of the engine aids due to variations in the angular speed of the crankshaft.

Thus the belt wears out quickly. Also, if no slip occurs between them, belt life is reduced due to changes in belt tension.

Japanese Patent Laid-Open No. 61-228153 discloses a solution to these problems.

In fact, the belt transfer device disclosed in this publication has a one-way clutch mounted between the rotational shaft of the engine aid and the pulley supported on the rotational shaft.

This clutch transmits the rotation of the crankshaft to the rotating shaft while the angular velocity of the crankshaft increases and blocks the transmission of rotation to the rotating shaft while decreasing.

In fact, while the angular speed of the crankshaft increases, the one-way clutch engages the pulley with the rotational shaft of the engine aid so that rotation of the crankshaft is transmitted to the rotational shaft.

When the axis of rotation begins to rotate faster than the pulley, the one-way clutch disengages, causing the axis of rotation to idle.

It is therefore possible for slip to not occur between the belt and the pulley to extend the life of the belt. However, such a belt transfer device has one problem.

If the one-way clutch is mounted without assistance between the rotating shaft and the pulley, the radial and moment loads on the pulley act on the one-way clutch.

Therefore, it is impossible for the one-way clutch to be operated with high precision and reliability.

It is an object of the present invention to provide a pulley with a one-way clutch that allows the pulley rotation in one direction to be transmitted to the rotating shaft of the engine aid with high precision and reliability, and smoothly rotates the pulley while idling.

According to the present invention, there is provided a belt driven pulley unit for transmitting the rotation of the crankshaft of the engine, which fluctuates within a narrow range of angular speed, to the rotational shaft of the engine auxiliaries, the pulley unit being mounted around the rotational axis of the engine auxiliaries and A pulley adapted to rotate in one direction through the belt, an inner member provided in the pulley and provided on the rotating shaft to rotate with the rotating shaft, and a rolling contact mounted between the pulley and the inner member to support radial and moment loads acting on the pulley To transfer the pulley's rotation to the rotating shaft when the angular velocity of the pulley during the one rotation of the bearing, the crankshaft exceeds the rotational axis of the engine aid, and also to the rotating shaft when the rotating shaft begins to rotate at a greater angular speed than the pulley. It is installed between the pulley and the inner member to block the rotational transmission of the pulley It consists of a one-way clutch with engaging elements.

Rolling contact bearings and one-way clutches can be arranged in many different ways.

For example, rolling contact bearings may be provided on both sides of the one-way clutch provided at the axial center portion between the pulley and the inner member. Further, the one-way clutch may be provided on at least one side of the rolling bearing provided in the axial central portion between the pulley and the inner member.

The engagement element of the one-way clutch may be a roller.

The one-way clutch may include an engagement element received in a wedge-shaped space formed between the cam surface formed on the inner circumference of the pulley and the cylindrical outer surface of the inner member.

It includes an outer ring with a cam formed on the inner circumferential surface of the pulley and a roller formation received in a wedge-shaped space formed between the cam surface and the cylindrical outer surface of the inner member. The rolling contact bearing includes a bowl housed in a raceway groove formed at the inner circumference of the pulley and the outer circumference of the inner member. Or the rolling contact bearing has an outer ring fitted in the pulley and / or an inner ring fitted on the inner member.

By mounting the rolling contact bearing and the one-way clutch between the pulley and the inner member, the rolling contact bearing supports the radial and moment loads applied on the pulley to make the one-way clutch operate with high accuracy and reliability. The pulley also rotates smoothly.

Other features and objects of the present invention will become apparent from the following description with reference to the accompanying drawings.

1 to 3 show a first embodiment of the present invention,

The pulley unit of this embodiment has a pulley 1 mounted around the rotation axis of the engine assist and a cylindrical inner member 2 provided inside the pulley 1 so as to rotate together with the rotation axis.

The one-way clutch 10 and the pair of rolling contact bearings 30a and 30b are mounted between the pulley 1 and the inner member 2. The one-way clutch 10 has a roller shape held in the wedge-shaped space 13 formed between the cam surface 11 formed on the inner circumference of the pulley 1 and the cylindrical outer surface 12 of the inner member 2. And a plurality of engagement elements 14.

The engagement element 14 is held in place by the cage 15.

As shown in FIG. 3, the cage 15 has a plurality of axial crossbars arranged at equal intervals in the circumferential direction so as to extend between the pair of annular members 16 spaced in the axial direction and these annular members 16. It includes (17). The rollers 14 are received in each pocket 18 formed between adjacent crossbars 17.

One of the annular members 16 has a flange 19 having an outer diameter larger than the outer diameter of the annular member 16.

In addition, the annular member 16 is provided along its outer edge with the protrusion 20 engaged with each cam surface 11 of the pulley 1.

The cage 15 has a flange 19 that engages in a groove 21 formed in the inner circumference of the pulley 1 to prevent its axial movement.

The cage 15 also prevents the projection 20 from rotating because it engages the cam surface 11 of the pulley 1 (FIG. 3). The engagement element 14 received in the pocket 18 of the cage 15 is in one direction by the elastic member 22 to engage both the cam surface of the pulley 1 and the cylindrical outer surface 12 of the inner member 2. Is pressurized.

Rolling contact bearings 30a and 30b are provided on both sides of the one-way clutch so as to effectively support radial loads and moment loads acting on the pulley 1.

One of the rolling contact bearings 30a and 30b, that is, the bearing 30a, is opposed to the bowl 33 and the raceway groove 31 accommodated in the raceway groove formed in the inner circumference of the pulley 1 at one end thereof and has an inner member. It has the raceway groove 32 formed in the outer periphery of (2).

Another rolling contact bearing 30b is a counterbore inner ring 34 press-fitted on the small diameter cylindrical portion 3 of the inner member 2 and having a raceway surface 35, and a raceway surface 35. And a plurality of bowls 37 accommodated in the raceway groove 36 formed in the inner circumference of the pulley 1 at the other end.

The rolling contact bearings 30a and 30b are sealed by the sealing member 38.

4 shows the pulley unit A of this embodiment and shows how this pulley unit is used. In practice, the pulley unit A is mounted on the rotary shaft 41 of the engine auxiliary such as an alternator driven by the crankshaft 40.

The belt 43 meshes with the pulley 1 of the pulley unit A and the pulley 42 firmly mounted on the crankshaft 40. Pulley unit (A) is a roller 14 of the one-way clutch 10, the cam surface 11 and the inner member (2) of the pulley (1) when the pulley (42) of the crankshaft 40 is rotated in the direction of the arrow It is mounted to engage with the cylindrical outer surface 12 of.

As the crankshaft 40 rotates, its angular velocity changes within a narrow range.

When the angular velocity increases, the rotation of the crankshaft 40 is transmitted to the pulley 1 of the pulley unit A through the belt 43.

In this state, the one-way clutch 10 is held in place to connect the pulley 1 and the inner member 2. Therefore, the rotation of the pulley 1 is transmitted to the rotating shaft of the engine aid through the inner member (2). When the angular velocity of the crankshaft 40 is reduced, the result is that the angular velocity of the rotary shaft 41 is faster than the angular velocity of the crankshaft 40 such that the one-way clutch is disengaged and the rotary shaft 41 is idling relative to the pulley 1 accordingly. .

In this state, the pulley 1 is completely separated from the rotation shaft 41 so that there is no force that resists the driving force transmitted from the belt 43 to the pulley 1.

This ensures that no slip occurs between the belt 43 and the pulley 1.

Thus, it is possible to extend the life of the belt 43.

We mounted the pulley unit shown in FIG. 1 on the rotating shaft of the alternator driven by the diesel engine, and measured the rotational speed change of the crank shaft, the pulley and the inner member.

The measurement results are shown in FIG.

Referring to the graph of FIG. 5, the rotational speed of the crankshaft varies ± 26% at 800 rpm while the rotational speed of the pulley is ± 25%.

In contrast, the rotational speed of the inner member changes only ± 4%.

From this graph, by using the pulley unit of this embodiment, the rotational speed change of the alternator can be greatly reduced, especially while the rotational speed of the crankshaft is low.

In fact, it is possible to smoothly rotate the rotating shaft of the alternator at a constant speed.

In the embodiment of FIG. 1, the pulley 1 is supported by a pair of rolling contact bearings 30a and 30b. Rolling contact bearings support radial and moment loads acting on the pulley 1.

Excessive force does not act on the one-way clutch 10.

Thus, the one-way clutch 10 operates with high precision and reliability.

The one-way clutch can be rotated smoothly while the pulley 1 is idling.

6 to 13 show another embodiment.

In the embodiment of FIG. 6, the rolling contact bearing 30 is provided at the center of the pulley 1 with respect to the width direction thereof.

The roller type one-way clutch 10 is provided on one side of the rolling contact bearing 30.

The one-way clutch 10 and the rolling contact bearing 30 are the same type used in the first embodiment.

Therefore, the description is omitted. Identical components are denoted by the same reference numerals.

The apparatus of this embodiment is operated in the same manner as the pulley units shown in FIGS. 1 to 3 and achieves the same result. Since only one rolling contact bearing is used for each one-way clutch, the device can be manufactured at low cost.

In the embodiment shown in FIG. 7, a pair of roller type one-way clutch 10 is provided on both sides of the rolling contact bearing 30 provided at the center of the pulley 1 with respect to the width direction thereof.

The pulley unit of this embodiment operates in the same manner as the pulley unit shown in FIGS. 1 to 3 and achieves the same result. Furthermore, two one-way clutches 10 are provided on both sides of the rolling contact bearing 30, at least one of which engages even if the pulley 1 is somewhat inclined to one side.

In the embodiment shown in FIGS. 8 to 10, the one-way clutch 10 is a roller type one-way clutch with a clutch ring 23 pressed into the pulley 1.

The outer ring 23 is formed with a plurality of cam surfaces 24 arranged in the circumferential direction at equal intervals on the inner circumference thereof. The wedge-shaped space 13 is formed between the cam surface 24 and the cylindrical outer surface 12 of the inner member 2.

As shown in FIG. 10, the cage 25 for holding the engagement element 14 in place connects the annular member 26, the annular flange 27 and the annular member 26 to the flange 27. A plurality of crossbars 28 are included. The annular member 26 has a projection 29 that engages with the cam surface 24 and thus prevents rotation of the cage 25.

Each of the rolling contact bearings 30a and 30b is press-fitted to each end of the pulley 1 and has an outer ring 50 having a raceway groove 51 and a circumference of the raceway groove 51 and the inner member 2. And a plurality of bowls 53 formed therein and received in the raceway grooves 52 opposite the raceway grooves 51.

The full flange 27 of the cage 25 is sandwiched between the outer ring 23 of the one-way clutch 10 and the outer ring of the rolling contact bearing 30b to prevent the cage 25 from moving in the axial direction. .

The apparatus of this embodiment operates in the same manner as the embodiment shown in FIGS. 1 to 3 and achieves the same result. In the embodiment of Fig. 11, each of the rolling contact bearings 30a and 30b has an outer ring 60 of each contact type having a counterbore shape.

The angular contact type outer ring 60 can be inserted into the pulley 1 from both sides after the bowl 53 is set in the raceway groove 52 of the inner member.

This pulley unit can thus be assembled more easily than the pulley unit shown in FIG.

In addition, the use of the bearing outer ring 60 of the angular contact type can eliminate the radial bearing clearance in the bearing or make it negative and thus improve the bearing strength.

In the embodiment of FIG. 12, the outer ring 60 of the clutch outer ring 23 and the other bearing 53 shown in FIG. 11 is formed as an integral outer ring 61.

The use of the integral outer ring 61 allows the number of components to be reduced in comparison with the pulley unit shown in FIG. Thus, the pulley unit can be assembled inexpensively.

In addition, the integral outer ring 61 provides a large contact area with the pulley 1.

Thus, even if the latter is inserted into the pulley 1 having a small gap, it is possible to transmit the required torque between the pulley 1 and the outer ring 61.

Therefore, the outer ring 61 can be fitted more easily.

In the embodiment of FIG. 13, the one-way clutch 10 has an outer ring 62 having a cam surface on its inner circumference, an inner ring 63 having a cylindrical outer surface, and an engagement element 64 mounted between the inner and outer rings. It consists of).

The rolling contact bearings 30a and 30b each have a bowl 67 mounted between the outer ring 65, the inner ring 66 and the rings 65 and 66, respectively. Such one-way clutch 10 and rolling contact bearings 30a and 30b are standard types that can be manufactured on a conventional production line.

Therefore, the pulley 1 and the inner member 2 can be easily manufactured at low cost.

In the embodiment of FIG. 13, the cam surface of the outer ring 62 of the one-way clutch 10 may be formed directly on the inner circumference of the pulley 1 and / or the outer rings of the rolling contact bearings 30a, 30b. 65 can be formed integrally with the pulleys and these arrangements are not shown.

In this embodiment, the roller is used as the engagement element of the one-way clutch.

However, sprags can be used as interlocking elements.

According to the pulley unit of the present invention, the rotation of the pulley in only one direction is transmitted to the inner member through the one-way clutch.

This pulley unit is used in the belt transmission to transmit the rotation of the crankshaft, which varies within a narrow range of angular velocity, to the rotary shaft of the alternator or other engine aids. It is possible to prevent and thus extend the belt life.

Since any radial or moment load is supported by the rolling contact bearings, no excessive force acts on the one-way clutch. Thus, the one-way clutch operates with high precision and reliability. The pulley can also be smoothly idled.

In an arrangement in which rolling contact bearings are provided on both sides of the one-way clutch, it is possible to prevent any non-uniform load from being applied to the one-way clutch.

Thus, the one-way clutch works more accurately and reliably.

The pulleys, inner members, one-way clutches and rolling contact bearings are assembled in a single unit so that this pulley unit can be easily fitted on any axis of rotation.

In one arrangement, the one-way clutch is provided between the pair of rolling bearings.

The one-way clutch operates with high precision and reliability because a pair of rolling contact bearings support any radial and moment loads acting on the pulley.

In another arrangement, a single rolling contact bearing is provided at the center of the pulley with respect to the width direction thereof while a single one-way clutch is provided at one side of the rolling contact bearing.

The unit can be manufactured inexpensively due to the small number of parts.

The method of claim 4, wherein the one-way clutch is provided on both sides of the single cloud contact bearing.

Thus, even if the pulley is slightly inclined, one of the one-way clutches can be operated so that the rotation of the pulley can be transmitted more reliably.

1 is a cross-sectional view of an embodiment of a pulley unit according to the present invention,

2 is a cross-sectional view on the line II-II of FIG. 1,

3 is a partial perspective view of the cage of the pulley,

4 is a schematic diagram of a pulley unit showing how the pulley unit is actually used,

5 is a graph showing that the coefficient change in the rotational speed of the inner member of the pulley unit is changed as the crankshaft speed when the pulley unit is mounted on the rotary shaft of the alternator driven by the diesel engine,

6 to 8 are cross-sectional views of another embodiment of a pulley unit,

9 is a cross-sectional view on line IX-IX of FIG. 8,

10 is a partial perspective view of the cage of the pulley unit,

11 through 13 are cross-sectional views of yet another embodiment of a pulley unit.

"Description of Symbols for Major Parts of Drawings"

A: pulley unit 1, 42: pulley

2: cylindrical inner member 10: one-way clutch

11, 24: cam surface 13: wedge space

14,64: engagement elements 15,25: cage

30: rolling contact bearing 40: crankshaft

41: shaft 43: belt

Claims (12)

In the belt drive pulley unit for transmitting the rotation of the crankshaft of the engine that fluctuates within a narrow range of angular velocity to the rotational shaft of the engine auxiliary, The pulley unit is mounted on a rotation shaft of the engine aid and rotates in one direction by the crankshaft through a belt, an inner member provided on the pulley and mounted on the rotation shaft to rotate with the rotation shaft, on the pulley. The rolling contact bearing mounted between the pulley and the inner member and the crankshaft while the crankshaft rotates in one rotation to support the acting radial load and the moment load when the angular velocity of the rotational axis of the engine With an engaging element mounted between the pulley and the inner member to transmit rotation of the pulley to the rotation axis and to block rotation of the pulley to the rotation axis when the rotation axis begins to rotate at a greater angle than the pulley. Belt sphere characterized by consisting of a one-way clutch Pulley unit. The belt drive pulley unit according to claim 1, wherein the one-way clutch is provided at an axial center portion between the pulley and the inner member, and one rolling contact bearing is provided at each side of the one-way clutch. . The belt drive pulley unit according to claim 1, wherein the rolling contact bearing is provided at an axial center portion between the pulley and the inner member, and the one-way clutch is provided at one side of the rolling bearing. The belt drive pulley unit according to claim 1, wherein the rolling contact bearing is provided at an axial center portion between the pulley and the inner member, and the one-way clutch is provided at each side of the rolling contact bearing. . The belt drive pulley unit according to any one of claims 1 to 4, wherein the engagement element of the one-way clutch is a roller. The belt drive pulley unit according to any one of claims 1 to 5, wherein the one-way clutch has an outer ring fitted in the pulley. The belt drive pulley unit according to any one of claims 1 to 6, wherein the one-way clutch has an inner ring fitted on the inner member. 6. The one-way clutch according to any one of claims 1 to 5, wherein the one-way clutch includes an engagement element received in a wedge-shaped space formed between a cam surface formed on an inner circumference of the pulley and a cylindrical outer surface of the inner member. Belt driven pulley unit. The belt drive pulley unit according to any one of claims 1 to 8, wherein the rolling contact bearing has an outer ring fitted to the pulley. 10. The belt drive pulley unit according to any one of claims 1 to 9, wherein the rolling contact bearing has an inner ring fitted on the inner member. The belt drive pulley according to claim 3 or 4, wherein the rolling contact bearing includes a raceway groove formed on an outer circumference of the inner member and a bowl accommodated in a raceway groove formed on an inner circumference of the pulley. Unit. 3. An inner ring of each contact type in which one of the pair of rolling contact bearings is press-fitted at one end of the inner member and has a raceway surface, and the raceway surface and the inner circumference of the pulley at one end. And a bowl accommodated in the raceway groove formed at the other end, and the other rolling contact bearing includes a raceway groove formed at the outer end of the inner member at the other end and a bowl accommodated in the raceway groove formed at the inner circumference of the pulley at the other end thereof. Belt drive pulley unit, characterized in that included.