JP2005337429A - Pulley unit having built-in clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pulley unit having a built-in clutch, eliminating distortion of a one-way clutch due to coupling of a rotating shaft and the pulley unit and influence of heat transmitted from accessories for an automobile to the clutch exerted on the clutch performance to perform stable clutch operation. <P>SOLUTION: In this pulley unit 10 having a built-in clutch, the inside diameter d1 of the inner peripheral surface of an annular member 14 in the clutch inner ring area (a) is smaller than the diameter d2 of the outer peripheral surface of the annular member 14 in a bearing fitting area (b), and a space part S is provided between a sleeve 12 and the annular member 14 outside in the radial direction of a female screw part 11a. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pulley unit with a built-in clutch, and more particularly, a pulley with a built-in clutch in which a clutch used for a motor for driving an auxiliary machine at the time of engine idle stop is built. The present invention relates to a pulley unit with a built-in clutch used in an auxiliary machine for automobiles.

  For example, an automobile auxiliary machine such as an alternator uses an engine as a drive source, and an endless belt or the like is provided between a driving pulley fixed to the crankshaft of the engine and a driven pulley fixed to a rotating shaft of the automobile auxiliary machine. The winding transmission member is wound and driven. In recent years, alternators and other automotive auxiliary machines have been improved in performance and output, and are used under severe conditions such as high rotation, high load, high temperature, and vibration.

  In addition, minute fluctuations in the rotational angular velocity of the engine induce flapping of the endless belt and belt squeal, which adversely affects the life of the endless belt and contributes to the generation of abnormal noise. For this reason, there is an increasing demand for a pulley unit with a built-in clutch in which a one-way clutch is incorporated in a pulley of an automobile auxiliary machine so that the influence of fluctuations in the rotational angular velocity of the engine on the automobile auxiliary machine is reduced.

  As shown in FIG. 12, the conventional pulley unit 200 with a built-in clutch includes a sleeve 202 that is screwed and fixed to a rotating shaft 201 of an automobile auxiliary machine (not shown) such as an alternator, and a radial direction of the sleeve 202. A pulley member 203 is provided on the outer side and is concentric with the sleeve 202 and has an outer peripheral surface formed with a belt groove 203a. A one-way clutch 204 is disposed between the outer peripheral surface 202a at the axial center of the sleeve 202 and the inner peripheral surface 203b of the pulley member 203, and the outer peripheral surface 202b at both axial ends of the sleeve 202 A pair of rolling bearings 205 is arranged between the inner peripheral surface 203b of the pulley member 203 so as to sandwich the one-way clutch 204.

  The one-way clutch 204 includes a clutch outer ring 206 that is press-fitted and fixed to the inner peripheral surface 203 b of the pulley member 203, a clutch inner ring 207 that is press-fitted and fixed to the outer peripheral surface 202 a of the sleeve 202, and the clutch outer ring 206 and the clutch inner ring 207. And a plurality of rollers 208 disposed rotatably. The one-way clutch 204 includes a clutch retainer 209 having a plurality of pockets that individually accommodate the rollers 208, and a spring 210 that elastically presses the rollers 208 in the locking direction.

  A plurality of ramp portions 207 a are formed on the outer peripheral surface of the clutch inner ring 207 at predetermined intervals in the circumferential direction, and the rollers 208 rotate in an annular clutch space formed by the ramp portions 207 a and the clutch outer ring 206. It is held freely.

  When the rotational angular velocity of the pulley member 203 is higher than the rotational angular velocity of the rotary shaft 201, the roller 208 is engaged in the clutch space between the ramp portion 207a and the clutch outer ring 206 by the wedge action, and the pulley member 203 The sleeve 202 becomes incapable of relative rotation (locked state), and the rotational force of the engine is transmitted to the rotating shaft 201. On the other hand, when the rotational angular velocity of the pulley member 203 is slower than the rotational angular velocity of the rotary shaft 201, the roller 208 is disengaged and the pulley member 203 and the sleeve 202 can be freely rotated (overrun state). .

In the prior art shown in FIG. 12, the sleeve 202 and the clutch inner ring 207 are configured separately, and the inner diameter d ₄ of the clutch inner ring 207 is the axis of the sleeve 202 to which the inner rings of the pair of rolling bearings 205 are fitted. It is larger than the outer diameter d ₃ of the outer peripheral surface 202b of the opposite ends.

  FIG. 13 shows another conventional pulley unit 220 with a built-in clutch. The pulley unit 220 with a built-in clutch is different from the prior art shown in FIG. 12 in the configuration of the sleeve and the inner ring of the clutch, and the inner ring of the clutch is formed integrally with the sleeve 221.

  In addition, as another conventional pulley unit with a built-in clutch, at least one of the outer peripheral surface of the sleeve and the inner peripheral surface of the clutch inner ring, a groove portion that causes biting by partially plastically deforming the other surface. A projection is formed to prevent the occurrence of creep (see, for example, Patent Document 1).

Furthermore, a one-way clutch is interposed between the pulley and the sleeve, and a shaft fixing portion (female screw portion) is formed on the side of the automobile accessory of the sleeve that does not overlap with the one-way clutch in the axial direction. There is known one in which the female screw portion is not disposed inward in the radial direction (see, for example, Patent Document 2).
JP 2001-90810 A (page 3-4, FIG. 1) JP 2002-221270 (page 3-5, FIG. 1)

  For example, in a pulley unit with a built-in clutch used in an alternator, a sleeve and a rotary shaft are fixed by screwing a female screw portion formed on a sleeve with a male screw portion formed on a rotary shaft of the alternator. For this reason, in order to prevent the pulley unit from falling off, it is necessary to increase the tightening strength of the threaded portion. However, as shown in FIGS. 12 and 13, when the tightening strength is increased, the deformation of the thread portion caused by the fastening of the screw is transmitted in the direction of the arrow P to deform the sleeves 202 and 221 and the clutch inner ring 207, and consequently The clutch space in which the plurality of rollers 208 are arranged is distorted, which is a factor that hinders the normal functioning of the clutch.

  In addition, a lubricant for lubricating the rollers 208 is sealed inside the one-way clutch 204, and the characteristic of the lubricant is one factor that affects the engagement operation of the clutch. The viscosity of the lubricant changes depending on the temperature. When the heat generated by the alternator is transmitted to the one-way clutch 204 via the sleeves 202 and 221 and the temperature of the lubricant rises, the viscosity of the lubricant decreases and an oil film is formed. There was a possibility that the roller 208 and the lamp portion 207a were abnormally worn and seized.

  Furthermore, in the pulley unit with a built-in clutch disclosed in Patent Document 1, the clutch inner ring is press-fitted into the sleeve by plastically deforming the outer peripheral surface of the sleeve or the outer peripheral surface of the clutch inner ring. There was a possibility of distorting the space.

  Further, the pulley unit with a built-in clutch disclosed in Patent Document 2 is configured so that the influence of screw fastening between the sleeve and the rotating shaft does not reach the clutch space. However, the coupling length between the rotating shaft and the pulley unit is not limited. Cannot be sufficiently long, and the pulley unit is cantilevered at one end of the rotating shaft. Therefore, if the pulley unit is eccentrically attached to the rotating shaft, or if a radial force acts on the pulley unit due to the tension of the endless belt, the pulley unit may be inclined and affect the clutch performance.

  The present invention has been made in view of the above-mentioned problems, and its purpose is to improve the clutch performance by the distortion of the one-way clutch due to the coupling of the rotating shaft and the pulley unit, and the heat conducted from the auxiliary equipment for automobiles. It is an object of the present invention to provide a pulley unit with a built-in clutch capable of eliminating the influence and performing a stable clutch action.

The above object of the present invention can be achieved by the following constitution.
(1) a pulley member having a belt groove formed on the outer peripheral surface;
A sleeve that can be rotated together with the rotary shaft by screwing and fixing a male screw portion formed on the rotary shaft to a female screw portion formed on the inner peripheral surface;
An annular member that is externally fixed to the sleeve and is arranged concentrically on the inside of the pulley member;
A plurality of torque transmission members provided between the inner peripheral surface of the pulley member and the outer peripheral surface of the annular member, and capable of transmitting torque between the pulley member and the sleeve, and individually accommodating the torque transmission member. A clutch comprising a clutch retainer having a plurality of pockets;
A clutch built-in pulley unit comprising a pair of rolling bearings disposed on both axial sides of the clutch and supporting the pulley member and the sleeve so as to be relatively rotatable;
The annular member includes a clutch inner ring region constituting a clutch inner ring of the clutch, and a bearing fitting region in which inner rings of the pair of rolling bearings are fitted, and an inner peripheral surface of the annular member in the clutch inner ring region. The inner diameter is smaller than the diameter of the outer peripheral surface of the annular member in the bearing fitting region,
A pulley unit with a built-in clutch, characterized in that a space is provided between the sleeve and the annular member on the radially outer side of the female screw part.
(2) The space portion is formed by providing an annular recess on at least one of the outer peripheral surface of the sleeve on the radially outer side of the female screw portion and the inner peripheral surface of the annular member on the radially outer side of the female screw portion. The pulley unit with a built-in clutch as set forth in (1), wherein
(3) The sleeve has a small-diameter portion whose outer peripheral surface is formed in the axial direction from the one axial end portion to the entire female screw portion, and a shaft extending from the small-diameter portion to the other axial end portion. A large-diameter portion formed in the direction,
The annular member has a large-diameter hole portion formed in the axial direction over a portion where an inner peripheral surface thereof is located radially outward of the female screw portion from the one axial end portion, and the large-diameter hole portion. A small-diameter hole formed in the axial direction over the other axial end, and
The space portion is formed by fitting the large-diameter hole portion of the annular member and the large-diameter portion of the sleeve, and the small-diameter hole portion of the annular member and the small-diameter portion of the sleeve. The pulley unit with a built-in clutch as set forth in (1).
(4) At least one of the annular member and the sleeve has an engaging portion that engages with each other and restricts relative axial movement, according to any one of (1) to (3). Pulley unit with built-in clutch.
(5) a pulley member having a belt groove formed on the outer peripheral surface;
A sleeve that can be rotated together with the rotary shaft by screwing and fixing a male screw portion formed on the rotary shaft to a female screw portion formed on the inner peripheral surface;
An annular member that is externally fixed to the sleeve and is arranged concentrically on the inside of the pulley member;
A plurality of torque transmission members provided between the inner peripheral surface of the pulley member and the outer peripheral surface of the annular member, and capable of transmitting torque between the pulley member and the sleeve, and individually accommodating the torque transmission member. A clutch comprising a clutch retainer having a plurality of pockets;
A clutch built-in pulley unit comprising a pair of rolling bearings disposed on both axial sides of the clutch and supporting the pulley member and the sleeve so as to be relatively rotatable;
The annular member includes a clutch inner ring region constituting a clutch inner ring of the clutch, and a bearing fitting region in which inner rings of the pair of rolling bearings are fitted, and an inner peripheral surface of the annular member in the clutch inner ring region. The inner diameter is smaller than the diameter of the outer peripheral surface of the annular member in the bearing fitting region,
A fastening allowance between the sleeve and the annular member on a radially outer side of the female screw portion is set to be smaller than a fastening allowance between the sleeve and the annular member in the remaining region. Pulley unit with built-in clutch.
(6) The torque transmission member of the clutch includes a first clutch raceway constituted by an inner peripheral surface of the pulley member, and a second clutch raceway constituted by an outer peripheral surface of the annular member in the clutch inner ring region. The pulley unit with a built-in clutch according to any one of (1) to (5), which is disposed in a clutch space formed between the two.
(7) The torque transmission member of the clutch is configured by a first clutch raceway configured by a clutch outer ring press-fitted into an inner peripheral surface of the pulley member, and an outer peripheral surface of the annular member in the clutch inner ring region. The pulley unit with a built-in clutch according to any one of (1) to (5), which is disposed in a clutch space formed between the second clutch raceway and the second clutch raceway.

  According to the pulley unit with a built-in clutch of the present invention, the inner diameter of the inner circumferential surface of the annular member in the clutch inner ring region is smaller than the diameter of the outer circumferential surface of the annular member in the bearing fitting region. A space is provided between the sleeve and the annular member. Thereby, the deformation of the sleeve (threaded portion) by screwing and fixing the rotating shaft to the sleeve is absorbed in the space portion and does not affect the one-way clutch, and the deformation of the one-way clutch can be suppressed. it can. Therefore, the function of the clutch can be maintained normally, the roller can be engaged and released reliably, and the function of the device incorporating the clutch built-in pulley unit can be ensured.

  Moreover, since the heat conducted from the sleeve is blocked by the space portion, the amount of heat conducted to the one-way clutch can be reduced as compared with the case where the space portion is not provided. This also makes it difficult for heat energy generated in an automobile auxiliary machine such as an alternator to be transmitted to the inside of the clutch, thereby preventing problems such as insufficient lubrication due to a decrease in the viscosity of the enclosed lubricant. Therefore, the pulley unit with a built-in clutch can be used for an auxiliary machine for automobiles having a large calorific value that is used under severe conditions such as high speed rotation and high load.

  Further, according to the pulley unit with a built-in clutch of the present invention, the space portion is formed on at least one of the outer peripheral surface of the sleeve radially outward of the female screw portion and the inner peripheral surface of the annular member radially outward of the female screw portion. Since it was formed by providing the annular recess, the space portion can be formed between the sleeve and the annular member by simple processing. In particular, when an annular recess is provided on either the outer peripheral surface of the sleeve or the inner peripheral surface of the annular member, the processing of the annular recess is not required on the other, and the manufacturing cost of the clutch built-in pulley unit can be further reduced.

  Further, according to the pulley unit with a built-in clutch of the present invention, the sleeve is formed from the small diameter portion and the large diameter portion, the annular member is formed from the small diameter hole portion and the large diameter hole portion, and the large diameter hole of the annular member is formed. Since the space portion is formed by fitting the portion and the large-diameter portion of the sleeve, and the small-diameter hole portion of the annular member and the small-diameter portion of the sleeve, the annular member and the sleeve can be easily processed. Further, the annular member and the sleeve can be easily press-fitted, and the space portion can be reliably formed at a predetermined position (outward in the radial direction of the female screw portion) simply by assembling the annular member and the sleeve.

  Further, according to the pulley unit with a built-in clutch of the present invention, the annular member and the sleeve are provided with at least one of the engaging portions that engage with each other and restrict relative axial movement. Positioning in the axial direction can be easily performed during press-fitting with the sleeve. Specifically, it can be easily assembled at a predetermined position by simply press-fitting the engagement portion to a position where it comes into contact with the mating member. Further, even if an axial force acts on the inner ring of the clutch due to misalignment of the belt or the like, the axial movement can be prevented by the engagement of the engaging portion. Therefore, the function of the clutch built-in pulley unit is stably maintained.

  According to the pulley unit with a built-in clutch of the present invention, the inner diameter of the inner circumferential surface of the annular member in the clutch inner ring region is smaller than the diameter of the outer circumferential surface of the annular member in the bearing fitting region, and the radial direction of the female thread portion Since the tightening allowance between the sleeve and the annular member on the outer side is set smaller than the tightening allowance between the sleeve and the annular member in the other region, the deformation of the annular member due to screw fastening is absorbed in the region where the tightening allowance is small. And deformation of the one-way clutch can be suppressed. The pulley unit with a built-in clutch according to the present invention is particularly effective when the screw fastening force is small or the Poisson's ratio is small. Therefore, the function of the clutch can be maintained normally, and the roller engagement and release operations can be performed reliably. Further, the processing of the sleeve and the annular member is easy.

  Hereinafter, a pulley unit with a built-in clutch according to each embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)
First, a pulley unit with a built-in clutch according to a first embodiment of the present invention will be described with reference to FIGS.
1 is a longitudinal sectional view of a pulley unit with a built-in clutch according to a first embodiment of the present invention, and FIG. 2 is a partial sectional view in FIG. 1 showing a state in which deformation of a sleeve due to screw fastening is absorbed by a space portion. is there.

As shown in FIG. 1, the pulley unit 10 according to the present embodiment has a female screw portion 12 a with which a male screw portion 11 a formed on a rotary shaft 11 of an automotive auxiliary machine (not shown) such as an alternator is screwed. A sleeve 12 formed on the surface is provided, and the sleeve 12 rotates together with the rotating shaft 11 by screwing and fixing the rotating shaft 11. Further, the pulley unit 10 includes a pulley member 13 which is disposed concentrically with the sleeve 12 on the outer side in the radial direction of the sleeve 12 and has a belt groove 13a formed on the outer peripheral surface thereof. An endless belt (not shown) is wound between the pulley member 13 and a drive pulley (not shown) provided on the crankshaft (not shown), and the endless belt is used to drive the rotational force of the engine. To the pulley member 13.
The belt groove 13a is formed into a V groove, a poly V groove, or a tooth groove according to the endless belt used.

  A separate annular member 14 is fitted and fixed to the outer peripheral surface 12 b of the sleeve 12 by press fitting, and the annular member 14 is disposed concentrically inside the pulley member 13. The annular member 14 has substantially the same axial length as that of the sleeve 12, and the inner peripheral surface 14 a thereof is press-fitted into the outer peripheral surface 12 b of the sleeve 12.

  An annular recess 12c is formed on the outer peripheral surface 12b of the sleeve 12 on the outer side in the radial direction of the female screw portion 12a over substantially the same length as the axial length of the female screw portion 12a. Further, when the sleeve 12 is fitted into the annular member 14 by press-fitting to the inner peripheral surface 14a of the annular member 14, the axial length of the female screw portion 12a is substantially equal to the axial position on the radially outer side of the female screw portion 12a. An annular recess 14b is formed over the same length. When the sleeve 12 is fitted to the annular member 14, the annular recess 12c of the sleeve 12 and the annular recess 14b of the annular member 14 are arranged to face each other, and the sleeve 12 and the annular member 14 are formed by the annular recess 12c and the annular recess 14b. An annular space S is formed between the fitting surfaces.

  Moreover, the outer peripheral surface 14c in the axial direction intermediate part of the cyclic | annular member 14 is formed larger diameter than the outer peripheral surface 14d in an axial direction both ends. A one-way clutch 15, which is a clutch of the present invention, is provided between the inner peripheral surface 13 b of the pulley member 13 and the outer peripheral surface 14 c at the intermediate portion in the axial direction of the annular member 14. Further, on both sides in the axial direction of the one-way clutch 15, a deep groove ball which is a pair of rolling bearings according to the present invention is provided between the inner peripheral surface 13b of the pulley member 13 and the outer peripheral surface 14d at both axial ends of the annular member 14. A bearing 16 is provided.

  Each ball bearing 16 supports the sleeve 12 and the pulley member 13 so as to be relatively rotatable while supporting a radial load applied to the pulley member 13. Each ball bearing 16 is an outer ring 17 having an outer ring raceway 17a on the inner peripheral surface, an inner ring 18 having an inner ring raceway 18a on the outer peripheral surface, and a rolling element provided so as to be able to roll between the outer ring raceway 17a and the inner ring raceway 18a. It has a plurality of balls 19 and a cage 20 that holds each ball 19. Further, seal rings 21 and 21 are provided between the inner peripheral surfaces of both ends of the outer ring 17 and the outer peripheral surfaces of both ends of the inner ring 18, and close both end openings of the bearing spaces of the ball bearings 16. The outer ring 17 is press-fitted to the inner peripheral surface 13b of the pulley member 13 with a margin, and the inner ring 18 is press-fitted to the outer peripheral surface 14d at both axial ends of the annular member 14 with a margin.

  The one-way clutch 15 has a clutch outer ring 22 that is fitted and fixed to the inner peripheral surface 13 b of the pulley member 13 by press fitting. A plurality of lamp portions 14e are formed at predetermined intervals in the circumferential direction on the outer peripheral surface 14c at the axially intermediate portion of the annular member 14. The annular clutch space formed by the inner peripheral surface of the clutch outer ring 22 that is the first clutch raceway of the present invention and each ramp portion 14e that is the second clutch raceway of the present invention includes the torque of the present invention. A plurality of rollers 23 serving as transmission members, a clutch retainer 24 having a plurality of pockets for individually accommodating the rollers 23, and a spring 25 are disposed. The clutch retainer 24 is externally fitted to the annular member 14 so as not to rotate relative to the annular member 14, and supports the rollers 23 so as to be slightly displaceable in the rolling and circumferential directions. In addition, the spring 25 is provided between the roller 23 and the pillar portion (not shown) of the clutch retainer 24 in the circumferential direction, and presses the roller 23 in the direction in which the clutch space becomes shallow, that is, in the locking direction. To do.

  When the rotational angular velocity of the pulley member 13 is higher than the rotational angular velocity of the rotary shaft 11, the one-way clutch 15 is engaged between the ramp portion 14 e and the clutch outer ring 22 by the wedge action, and the pulley member 13. And the sleeve 12 become relatively unrotatable (locked state), and the rotational force is transmitted from the pulley member 13 to the rotating shaft 11. On the other hand, when the rotational angular velocity of the pulley member 13 is slower than the rotational angular velocity of the rotating shaft 11, the engagement of the rollers 23 is released and the relative rotation between the pulley member 13 and the sleeve 12 becomes free (overrun state). .

Here, the annular member 14 includes a clutch inner ring region a constituting a clutch inner ring of the one-way clutch 15 on the outer peripheral surface 14c in the axial intermediate portion, and inner rings 18 of the ball bearings 16 on the outer peripheral surfaces 14d at both axial ends. The bearing fitting area | region b fitted with an internal peripheral surface is comprised. Then, the inner diameter d ₁ of the inner peripheral surface 14a of the annular member 14 of the clutch inner ring region a has a smaller diameter than the diameter d ₂ of the outer circumferential surface 14d of the annular member 14 in the bearing fitting region b. Further, the clutch inner ring region a is positioned so as to overlap the female screw portion 12a in the axial direction, and in the present embodiment, substantially coincides with the axial direction. Of course, the clutch inner ring region a also overlaps with the space S in the axial direction, and in the present embodiment, substantially coincides with the axial direction.

  In the pulley unit with a built-in clutch configured as described above, as shown in FIG. 2, the sleeve 12 is engaged in the radial direction by the fastening force by screwing the female screw portion 12a of the sleeve 12 and the male screw portion 11a of the rotating shaft 11. Although deformed outward (in the direction of the arrow P), the deformation of the sleeve 12 is absorbed by the space S formed between the sleeve 12 and the annular member 14. There is no effect. Therefore, deformation of the clutch space formed by the inner peripheral surface of the clutch outer ring 22 and each ramp portion 14e is suppressed, and a normal clutch function is maintained.

Further, by providing the space S between the sleeve 12 and the annular member 14, the amount of heat conducted from the sleeve 12 to the annular member 14 is greatly reduced. Generally, the amount of conduction heat is obtained by the following equation.
Q = λ × θ × A × t / σ
Here, Q is the total heat of conduction, λ is the thermal conductivity, θ is the temperature difference, A is the surface area, t is the time, and σ is the thickness of the wall through which heat is conducted.

It is known that the thermal conductivity λ of a gas is much smaller than the thermal conductivity λ of a solid. Specifically, the thermal conductivity λ of air existing in the space S is much smaller than the thermal conductivity λ of the solid sleeve 12 and the annular member 14, and from the sleeve 12 through the space S from the above equation. The amount of heat conducted to the annular member 14 is extremely small, and the amount of heat conducted in the space S can be ignored.
Thus, the contact area A between the sleeve 12 and the annular member 14 when the space portion S is provided is smaller than that when the space portion S is not provided, and the temperature difference θ, time t, and wall thickness. It can be seen that when σ is the same condition, the heat of conduction is reduced.

Therefore, the amount of heat that is transmitted to the one-way clutch 15 by the heat energy generated in the auxiliary equipment for automobiles such as an alternator is greatly reduced, and the temperature rise of the one-way clutch 15 is greatly suppressed. Therefore, lubrication failure due to a decrease in the viscosity of the lubricant does not occur, abnormal wear or seizure of the one-way clutch 15 is prevented, and the function can be maintained over a long period of time.
Further, in the configuration of the present embodiment, since the amount of heat conducted to the pair of deep groove ball bearings 16 is also reduced, the same effect can be obtained for the lubricant in the bearing space of the pair of deep groove ball bearings 16.

According to the pulley unit 10 with a built-in clutch of the present embodiment, the inner diameter d ₁ of the inner peripheral surface of the annular member 14 in the clutch inner ring region a is in the bearing fitting region b in which the inner ring 18 of the pair of rolling bearings 16 is fitted. It has a smaller diameter than the diameter d ₂ of the outer circumferential surface 14d of the annular member 14, and between the sleeve 12 and the annular member 14 in the radially outward of the female screw portion 12a, the space portion S is provided. As a result, the deformation of the sleeve 12 (female screw portion 12a) caused by screwing and fixing the rotary shaft 11 to the sleeve 12 is absorbed in the space S and does not affect the one-way clutch 15, and the one-way clutch 15 Can be suppressed. Accordingly, the clutch function can be maintained normally, the roller 23 can be engaged and disengaged reliably, and the function of the device incorporating the clutch built-in pulley unit 10 can be ensured.

  Moreover, since the heat conducted to the sleeve 12 is blocked by the space portion S, the amount of heat Q conducted to the one-way clutch 15 can be reduced as compared with the case where the space portion S is not provided. This also makes it difficult for heat energy generated in an automobile auxiliary machine such as an alternator to be transmitted to the inside of the clutch, thereby preventing problems such as insufficient lubrication due to a decrease in the viscosity of the enclosed lubricant. Therefore, the pulley unit 10 with a built-in clutch according to the present embodiment can perform a stable clutch engagement operation even in an alternator having a large power generation load or a large calorific value used under severe conditions such as high speed rotation and high load. it can.

Further, the inner diameter d ₁ of the inner peripheral surface 14a of the annular member 14 of the clutch inner ring region a, since it has a smaller diameter than the diameter d ₂ of the outer circumferential surface 14d of the annular member 14 in the bearing fitting region b, the annular member 14 Can be thickened. As a result, the stress acting on the annular member, particularly the stress concentration generated in the ramp portion, can be reduced to prevent the annular member 14 constituting the clutch inner ring from cracking.

  Further, since the space portion S is constituted by the annular recess portion 12c of the sleeve 12 and the annular recess portion 14b of the annular member 14, the space portion S can be formed between the sleeve 12 and the annular member 14 by simple processing. The pulley unit 10 with a built-in clutch can be manufactured at low cost.

  As shown in FIG. 2, the thickness of the space S in the radial direction is preferably such that the deformation of the sleeve 12 due to screw fastening is absorbed by the space S and is not transmitted to the clutch space. It is sufficient that the thickness be such that the clutch function is not hindered even if the clutch path is changed.

(Second Embodiment)
Next, a pulley unit with a built-in clutch according to a second embodiment of the present invention will be described with reference to FIG. Note that the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  FIG. 3 is a longitudinal sectional view of a pulley unit with a built-in clutch according to a second embodiment of the present invention. As shown in FIG. 3, the pulley unit 30 with a built-in clutch according to the second embodiment is provided with an annular recess 14b only in the annular member 14, and the sleeve 31 having an internal thread portion 31a formed on the inner peripheral surface is annular. The point which the recessed part is not formed differs from the pulley unit 10 with a built-in clutch of 1st Embodiment.

Therefore, according to the pulley unit 30 with a built-in clutch of the present embodiment, the space portion S is formed by providing the annular recess 14b only on the inner peripheral surface of the annular member 14 on the radially outer side of the female screw portion 31a. The space S can be formed between the sleeve 31 and the annular member 14 by simpler processing, and the pulley unit 30 with a built-in clutch can be manufactured at a lower cost.
Other configurations and operations are the same as those in the first embodiment.

(Third embodiment)
Next, a pulley unit with a built-in clutch according to a third embodiment of the present invention will be described with reference to FIG. Note that the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  FIG. 4 is a longitudinal sectional view of a pulley unit with a built-in clutch according to a third embodiment of the present invention. As shown in FIG. 4, the clutch built-in pulley unit 40 of the third embodiment is provided with an annular recess 12 c only in the sleeve 12, and the annular member 41 is not formed with an annular recess. It differs from the clutch built-in type pulley unit 10 of a form.

Therefore, according to the pulley unit 40 with a built-in clutch of the present embodiment, the space portion S is formed by providing the annular recess 12c only on the outer peripheral surface of the sleeve 12 on the radially outer side of the female screw portion 12a. The space portion S can be formed between the sleeve 12 and the annular member 41 by simple processing, and the pulley unit 40 with a built-in clutch can be manufactured at a lower cost.
Other configurations and operations are the same as those in the first embodiment.

(Fourth embodiment)
Next, a pulley unit with a built-in clutch according to a fourth embodiment of the present invention will be described with reference to FIG. Note that the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  FIG. 5 is a longitudinal sectional view of a pulley unit with a built-in clutch according to a fourth embodiment of the present invention. As shown in FIG. 5, in the pulley unit 50 with a built-in clutch according to the fourth embodiment, the sleeve 51 includes a small-diameter portion 51b on the outer peripheral surface and a large-diameter portion 51c having a larger diameter than the small-diameter portion 51b. . The small diameter portion 51b is formed in the axial direction from one axial end portion of the sleeve 51 to the entire internal thread portion 51a, and the large diameter portion 51c extends from the small diameter portion 51b to the other axial end portion of the sleeve 51. It is formed in the axial direction. The annular member 52 includes a small-diameter hole 52b on the inner peripheral surface and a large-diameter hole 52c having an inner diameter larger than that of the small-diameter hole 52b. The large-diameter hole portion 52c is formed in the axial direction from the one axial end portion of the annular member 52 to a portion located radially outward of the female screw portion 51a, and the small-diameter hole portion 52b is the large-diameter hole portion 52c. To the other end of the annular member 52 in the axial direction. The small-diameter portion 51b of the sleeve 51 and the small-diameter hole portion 52b of the annular member 52 are formed on the front side (automobile accessory side).

  The outer diameter of the small diameter portion 51 b of the sleeve 51 is substantially the same as the inner diameter of the small diameter hole portion 52 b of the annular member 52, and the outer diameter of the large diameter portion 51 c of the sleeve 51 is the same as that of the large diameter hole portion 52 c of the annular member 52. It is almost the same as the inner diameter. Then, the large-diameter hole portion 52c of the annular member 52 and the large-diameter portion 51c of the sleeve 51, and the small-diameter hole portion 52b of the annular member 52 and the small-diameter portion 51b of the sleeve 51 are fitted together by press-fitting. The sleeve 51 is assembled. At this time, between the annular member 52 and the sleeve 51 on the radially outer side of the female screw portion 51a, the axial length of the female screw portion 51a is increased by the large diameter hole portion 52c of the annular member 52 and the small diameter portion 51b of the sleeve 51. A space S having substantially the same axial length is formed.

According to the clutch built-in pulley unit 50 of the present embodiment, the sleeve 51 is composed of a small diameter part 51b and a large diameter part 51c, and the annular member 52 is composed of a small diameter hole part 52b and a large diameter hole part 52c. The space S is formed by fitting the large-diameter hole portion 52c of the member 52 and the large-diameter portion 51c of the sleeve 51, and the small-diameter hole portion 52b of the annular member 52 and the small-diameter portion 51b of the sleeve 51. Thereby, the process of the annular member 52 and the sleeve 51 becomes easy. In addition, the annular member 52 and the sleeve 51 can be easily press-fitted, and the space portion S can be secured at a predetermined position (outward in the radial direction of the female screw portion 51a) simply by fitting the annular member 52 and the sleeve 51 together. Can be formed.
Other configurations and operations are the same as those in the first embodiment.

  As a modified example of the fourth embodiment, the pulley unit 60 with a built-in clutch includes a large-diameter portion 51c of the sleeve 51 and a large-diameter hole portion 52c of the annular member 52 as shown in FIG. Contrary to the clutch built-in type pulley unit 50, the pulley unit 50 may be disposed on the front side (automotive auxiliary machine side), and has the same effect.

(Fifth embodiment)
Next, a pulley unit with a built-in clutch according to a fifth embodiment of the present invention will be described with reference to FIG. Note that the same or equivalent parts as those in the fourth embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  FIG. 7 is a longitudinal sectional view of a pulley unit with a built-in clutch according to a fifth embodiment of the present invention. As shown in FIG. 7, the clutch-embedded pulley unit 70 of the fifth embodiment is different from the clutch-embedded pulley unit 50 of the fourth embodiment in that an engagement portion 71 d is formed on the annular member 71.

  The annular member 71 is composed of a small-diameter hole 71b on the inner peripheral surface and a large-diameter hole 71c having an inner diameter larger than that of the small-diameter hole 71b. The large-diameter hole portion 71c is formed in the axial direction from the axial one end portion of the annular member 71 to the portion located radially outward of the female screw portion 51a, and the small-diameter hole portion 71b is the large-diameter hole portion 71c. To the other end of the annular member 71 in the axial direction. An annular engaging portion 71d that protrudes inward in the radial direction is formed at an intermediate portion of the large-diameter hole portion 71c of the annular member 71.

Similarly to the pulley unit 50 with a built-in clutch, the small-diameter portion 51b of the sleeve 51 and the small-diameter hole portion 71b of the annular member 71 are formed on the front side (automobile accessory side), and the large-diameter portion 51c, large-diameter hole portion 71c is formed on the opposite side.
The engaging portion 71d is positioned so as to engage with the step portion of the small diameter portion 51b and the large diameter portion 51c of the sleeve 51 when the sleeve 51 is fitted into the annular member 71 by press fitting. A space portion S having an axial length substantially the same as the axial length of the female screw portion 51a is formed between the annular member 71 and the sleeve 51 on the radially outer side of the female screw portion 51a.

  Further, the rotating shaft 11 of the present embodiment is formed as a stepped shaft in which a male screw portion 11 a that is screwed into the female screw portion 51 a of the sleeve 51 has a small diameter, and the step portion 11 b of the rotating shaft 11 is formed with the sleeve 51 and an annular shape. The member 71 is in contact with the side surface of the front side (automobile accessory side). Accordingly, the axial movement of the annular member 71 in the direction of arrow A is prevented by the engaging portion 71d engaged with the stepped portion of the sleeve 51, and the axial movement in the direction of arrow B is prevented by the stepped portion of the rotating shaft 11. Blocked by 11b. As a result, the sleeve 51 and the annular member 71 do not move relative to each other in the axial direction.

According to the pulley unit 70 with a built-in clutch of the present embodiment, the engaging portion 71 d that engages with each other and restricts the relative axial movement with the sleeve 51 is provided in the large-diameter hole portion 71 c of the annular member 71. Therefore, the axial positioning can be easily performed when the annular member 71 and the sleeve 51 are assembled. Specifically, it can be assembled at a predetermined position simply by press-fitting the engaging portion 71d to a position where it comes into contact with the stepped portion of the sleeve 51. Further, even if an axial force acts on the annular member 71 constituting the clutch inner ring due to misalignment of the belt or the like, the axial movement can be restricted by the engagement of the engaging portion 71d. Accordingly, the function of the clutch built-in pulley unit 70 is stably maintained.
Other configurations and operations are the same as those in the first embodiment.

  As a modification of the fifth embodiment, as shown in FIG. 8, the pulley unit 80 with a built-in clutch includes a large-diameter portion 51c of the sleeve 51 and a large-diameter hole portion 71c of the annular member 71. Contrary to the pulley unit 70 with a built-in clutch, the pulley unit 70 may be disposed on the front side (auxiliary side for automobiles), and has the same effect.

(Sixth embodiment)
Next, a pulley unit with a built-in clutch according to a sixth embodiment of the present invention will be described with reference to FIG. Note that the same or equivalent parts as those in the fourth embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  FIG. 9 is a longitudinal sectional view of a pulley unit with a built-in clutch according to a sixth embodiment of the present invention. As shown in FIG. 9, in the pulley unit 90 with a built-in clutch according to the sixth embodiment, the sleeve 91 has a small-diameter portion 91b and a small-diameter portion with an outer peripheral surface similar to the pulley unit 50 with a built-in clutch in the fourth embodiment. A large-diameter portion 91c having a larger diameter than 91b. The small diameter portion 91b is formed in the axial direction from one axial end portion of the sleeve 91 to the entire internal thread portion 91a, and the large diameter portion 91c extends from the small diameter portion 91b to the other axial end portion of the sleeve 91. It is formed in the axial direction. The annular member 92 includes a small-diameter hole 92b on the inner peripheral surface and a large-diameter hole 92c having an inner diameter larger than that of the small-diameter hole 92b. The large-diameter hole portion 92c is formed in the axial direction from the one axial end portion of the annular member 92 to a portion located radially outward of the female screw portion 91a, and the small-diameter hole portion 92b is the large-diameter hole portion 92c. Is formed in the axial direction over the other axial end of the annular member 92. The small-diameter portion 91b of the sleeve 91 and the small-diameter hole portion 92b of the annular member 92 are arranged on the front side (automobile accessory side), and the large-diameter portion 91c of the sleeve 91 and the large-diameter hole portion of the annular member 92 are arranged. 92c is arranged on the opposite side.

  An annular engagement portion 92d that protrudes inward in the radial direction is formed at a side end portion of the small-diameter hole portion 92b of the annular member 92. The axial length of the sleeve 91 is shortened by the thickness of the engaging portion 92d, and the engaging portion 92d engages with the front side (automobile accessory side) end surface of the sleeve 91. The step portion 11b of the rotating shaft 11 is in contact with the front side (automobile accessory side) side surface (side surface of the engaging portion 92d) of the annular member 92. Accordingly, the axial movement of the annular member 92 in the direction of arrow A is prevented by the engaging portion 92d that engages with the front end surface of the sleeve 91, and the axial movement in the direction of arrow B is performed by the step of the rotary shaft 11. Blocked by the part 11b. Thereby, the relative axial movement of the sleeve 91 and the annular member 92 is prevented.

Therefore, according to the pulley unit 90 with a built-in clutch according to the present embodiment, the engaging member 92d that engages with each other and restricts relative axial movement is provided at the end of the annular member 92. And the sleeve 91 can be easily positioned in the axial direction, and can be accurately assembled at a predetermined position simply by press-fitting the engaging portion 92d to a position where it abuts against the mating member. Even if an axial force acts on the inner ring of the clutch due to misalignment of the belt or the like, the axial movement can be restricted by the engagement of the engaging portion 92d. Therefore, the function of the clutch built-in pulley unit 90 is stably maintained.
Other configurations and operations are the same as those of the fourth embodiment.

  FIG. 10 shows a clutch built-in pulley unit 100, which is a modification of the sixth embodiment. The sleeve 101 includes a small-diameter portion 101b on the outer peripheral surface and a large-diameter portion 101c having a larger diameter than the small-diameter portion 101b. The small diameter portion 101b is formed in the axial direction from one axial end portion of the sleeve 101 to the entire internal thread portion 101a, and the large diameter portion 101c extends from the small diameter portion 101b to the other axial end portion of the sleeve 101. It is formed in the axial direction. The annular member 102 includes a small-diameter hole 102b on the inner peripheral surface and a large-diameter hole 102c having an inner diameter larger than that of the small-diameter hole 102b. The large-diameter hole portion 102c is formed in the axial direction from the one axial end portion of the annular member 102 to a portion located radially outward of the female screw portion 101a, and the small-diameter hole portion 102b is the large-diameter hole portion 102c. Is formed in the axial direction over the other axial end of the annular member 102.

  In this modification, the large-diameter portion 101c of the sleeve 101 and the large-diameter hole portion 102c of the annular member 102 are disposed on the front side (automobile auxiliary device side), contrary to the pulley unit 90 with a built-in clutch of the sixth embodiment. ing. Further, a hook-like engagement portion 101d protruding radially outward is formed on the front side end surface of the sleeve 101, and the axial length of the annular member 102 is shortened by the thickness of the engagement portion 101d. Is formed. Thus, the engaging portion 101d engages with the front side (automotive accessory side) end surface of the annular member 102, while the step portion 11b of the rotating shaft 11 faces the front side (automotive accessory side) side of the sleeve 101. By abutting on (the side surface of the engaging portion 101d), the same effect is achieved.

(Seventh embodiment)
Next, a pulley unit with a built-in clutch according to a seventh embodiment of the present invention will be described with reference to FIG. Note that the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  FIG. 11 is a longitudinal sectional view of a pulley unit with a built-in clutch according to a seventh embodiment of the present invention. As shown in FIG. 11, the pulley unit 110 with a built-in clutch according to the seventh embodiment includes a sleeve 111 in which an internal thread portion 111 a is formed on the inner peripheral surface and the rotating shaft 11 is screwed and fixed. Rotates together with the rotating shaft 11. A separate annular member 112 is fitted and fixed to the outer peripheral surface 111 b of the sleeve 111 by press fitting, and the annular member 112 is arranged concentrically with the pulley member 13. The annular member 112 has an axial length substantially the same as that of the sleeve 111, and the inner peripheral surface 112 a is press-fitted to the outer peripheral surface 111 b of the sleeve 111 over the axial length.

  The tightening allowance when the sleeve 111 and the annular member 112 are press-fitted is set differently in the axial direction. Specifically, the fastening allowance between the outer peripheral surface 111b of the sleeve 111 and the inner peripheral surface 112a of the annular member 112 on the radially outer side of the female threaded portion 111a of the sleeve 111 (in the range of the region 1 in FIG. 11) It is set smaller than the fastening allowance between the outer peripheral surface 111b of the sleeve 111 and the inner peripheral surface 112a of the annular member 112 in the region (range of the regions m and n in FIG. 11).

Therefore, according to the pulley unit 110 with a built-in clutch according to the present embodiment, the distortion deformation in the radial direction of the sleeve 111 that occurs when the rotary shaft 11 is screwed and fixed to the female screw portion 111a of the sleeve 111 is the female screw portion 111a. Is absorbed by the elastic deformation of the sleeve 111 and the annular member 112 in a region with a small tightening margin set radially outward, and thus the annular member 112 and, consequently, the one-way clutch 15 is not affected. The pulley unit 110 with a built-in clutch according to the present embodiment in which the sleeve 111 and the annular member 112 are not provided with the annular concave portion has a Poisson's ratio especially when the screw fastening force is small, the Young's modulus of the sleeve 111 and the annular member 112 is large. Effective when small.
Other configurations and operations are the same as those in the first embodiment.

  In addition, the interference allowance of this embodiment can be set using the method demonstrated in 1st Embodiment-6th Embodiment in which the space part S was formed. For example, in order to reduce the interference in the region l, an annular recess may be provided on at least one of the outer peripheral surface of the sleeve and the inner peripheral surface of the annular member as in the first to third embodiments. You may make it provide by fitting the annular member which consists of a sleeve which consists of a small diameter part and a large diameter part, and a small diameter hole part, and a large diameter hole part like a form. Further, as in the fifth and sixth embodiments, at least one of the sleeve and the annular member may be configured to have an engaging portion that engages with each other and restricts relative axial movement.

Note that the present invention is not limited to the above-described embodiments and modifications, and modifications and improvements can be made as appropriate.
In this embodiment, the clutch space of the one-way clutch is a first clutch raceway constituted by a clutch outer ring press-fitted into the inner peripheral surface of the pulley member, and a second clutch raceway constituted by a ramp portion of the annular member. However, the first clutch raceway may be formed by an inner peripheral surface of a pulley member in which a clutch outer ring is integrated.

  The pulley unit has been described as having a ramp portion formed on an annular member constituting the clutch inner ring. However, the pulley unit is not limited to this. For example, the pulley unit is press-fitted into the inner peripheral surface of the pulley member or the pulley member. A pulley unit in which a ramp portion is formed on the inner peripheral surface of the outer ring of the clutch may also be used.

Further, in the one-way clutch of the present embodiment, the roller is used as the torque transmission member. However, the sprag may be disposed between the facing clutch raceways as long as the torque can be transmitted between the pulley member and the sleeve. There is no particular limitation. The spring applied to the one-way clutch may be a leaf spring or a coil spring, and is not particularly limited as long as it can press the torque transmitting member toward the lock side.
In the present embodiment, the clutch is a one-way clutch, but it may be a two-way clutch that allows selection of the direction in which the wedge action is performed.

The pulley member of this embodiment is driven by a belt, but may be configured to be driven by a belt and coupling rubber.
Further, the rolling bearings disposed on both sides in the axial direction of the one-way clutch may be a rolling bearing of a type other than the deep groove ball bearing.
Furthermore, the pulley unit of the present invention is not limited to a pulley unit incorporated in an automobile auxiliary machine, and can be applied to any device in which a one-way clutch is incorporated.

It is a longitudinal cross-sectional view of the pulley unit with a built-in clutch which is 1st Embodiment of this invention. It is a fragmentary sectional view in Drawing 1 showing the state where the deformation of the sleeve by screw fastening is absorbed by the space part. It is a longitudinal cross-sectional view of the pulley unit with a built-in clutch which is 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the pulley unit with a built-in clutch which is 3rd Embodiment of this invention. It is a longitudinal cross-sectional view of the pulley unit with a built-in clutch which is 4th Embodiment of this invention. It is a longitudinal cross-sectional view of the modification of the pulley unit with a built-in clutch of 4th Embodiment of this invention. It is a longitudinal cross-sectional view of the pulley unit with a built-in clutch which is 5th Embodiment of this invention. It is a longitudinal cross-sectional view of the modification of the pulley unit with a built-in clutch of 5th Embodiment of this invention. It is a longitudinal cross-sectional view of the pulley unit with a built-in clutch which is 6th Embodiment of this invention. It is a longitudinal cross-sectional view of the modification of the pulley unit with a built-in clutch of 6th Embodiment of this invention. It is a longitudinal cross-sectional view of the pulley unit with a built-in clutch which is 7th Embodiment of this invention. It is a longitudinal cross-sectional view of the pulley unit of a prior art. It is a longitudinal cross-sectional view of the pulley unit of another prior art.

Explanation of symbols

10, 30, 40, 50, 60, 70, 80, 90, 100, 110 Pulley unit with built-in clutch 11 Rotating shaft 11a Male thread portion 12, 31, 51, 91, 101, 111 Sleeve 12a, 31a, 51a, 91a, 101a, 111a Female thread portion 12c, 14b Annular recess 13 Pulley member 14, 41, 52, 71, 92, 102, 112 Annular member 15 One-way clutch (clutch)
16 Deep groove ball bearings (rolling bearings)
18 Rolling bearing inner ring 23 Roller (torque transmission member)
24 Clutch retainer S Space portion 51b, 91b, 101b Small diameter portion of sleeve 51c, 91c, 101c Large diameter portion of sleeve 52b, 71b, 92b, 102b Small diameter hole portion of annular member 52c, 71c, 92c, 102c Large annular member Diameter hole portion 71d, 92d, 101d Engaging portion a Clutch inner ring region b Bearing fitting region

Claims (7)

A pulley member having a belt groove formed on the outer peripheral surface;
A sleeve that can be rotated together with the rotary shaft by screwing and fixing a male screw portion formed on the rotary shaft to a female screw portion formed on the inner peripheral surface;
An annular member that is externally fixed to the sleeve and is arranged concentrically on the inside of the pulley member;
A plurality of torque transmission members provided between the inner peripheral surface of the pulley member and the outer peripheral surface of the annular member, and capable of transmitting torque between the pulley member and the sleeve, and individually accommodating the torque transmission member. A clutch comprising a clutch retainer having a plurality of pockets;
A clutch built-in pulley unit comprising a pair of rolling bearings disposed on both axial sides of the clutch and supporting the pulley member and the sleeve so as to be relatively rotatable;
The annular member includes a clutch inner ring region constituting a clutch inner ring of the clutch, and a bearing fitting region in which inner rings of the pair of rolling bearings are fitted, and an inner peripheral surface of the annular member in the clutch inner ring region. The inner diameter is smaller than the diameter of the outer peripheral surface of the annular member in the bearing fitting region,
A pulley unit with a built-in clutch, characterized in that a space is provided between the sleeve and the annular member on the radially outer side of the female screw part.   The space portion is formed by providing an annular recess on at least one of the outer peripheral surface of the sleeve on the radially outer side of the female screw portion and the inner peripheral surface of the annular member on the radial outer side of the female screw portion. The pulley unit with a built-in clutch according to claim 1. The sleeve has an outer peripheral surface formed in the axial direction from one end portion in the axial direction to the entire internal thread portion and in the axial direction from the small diameter portion to the other end portion in the axial direction. A large diameter portion, and
The annular member has a large-diameter hole portion formed in the axial direction over a portion where an inner peripheral surface thereof is located radially outward of the female screw portion from the one axial end portion, and the large-diameter hole portion. A small-diameter hole formed in the axial direction over the other axial end, and
The space portion is formed by fitting the large-diameter hole portion of the annular member and the large-diameter portion of the sleeve, and the small-diameter hole portion of the annular member and the small-diameter portion of the sleeve. The pulley unit with a built-in clutch according to claim 1.   The pulley with built-in clutch according to any one of claims 1 to 3, wherein at least one of the annular member and the sleeve has an engaging portion that engages with each other and restricts relative axial movement. unit. A pulley member having a belt groove formed on the outer peripheral surface;
A sleeve that can be rotated together with the rotary shaft by screwing and fixing a male screw portion formed on the rotary shaft to a female screw portion formed on the inner peripheral surface;
An annular member that is externally fixed to the sleeve and is arranged concentrically on the inside of the pulley member;
A plurality of torque transmission members provided between the inner peripheral surface of the pulley member and the outer peripheral surface of the annular member, and capable of transmitting torque between the pulley member and the sleeve, and individually accommodating the torque transmission member. A clutch comprising a clutch retainer having a plurality of pockets;
A clutch built-in pulley unit comprising a pair of rolling bearings disposed on both axial sides of the clutch and supporting the pulley member and the sleeve so as to be relatively rotatable;
The annular member includes a clutch inner ring region constituting a clutch inner ring of the clutch, and a bearing fitting region in which inner rings of the pair of rolling bearings are fitted, and an inner peripheral surface of the annular member in the clutch inner ring region. The inner diameter is smaller than the diameter of the outer peripheral surface of the annular member in the bearing fitting region,
A fastening allowance between the sleeve and the annular member on a radially outer side of the female screw portion is set to be smaller than a fastening allowance between the sleeve and the annular member in the remaining region. Pulley unit with built-in clutch.   The torque transmission member of the clutch is between a first clutch raceway constituted by an inner peripheral surface of the pulley member and a second clutch raceway constituted by an outer peripheral surface of the annular member in the clutch inner ring region. The pulley unit with a built-in clutch according to any one of claims 1 to 5, wherein the pulley unit is incorporated in the formed clutch space.   The torque transmission member of the clutch includes a first clutch raceway configured by a clutch outer ring press-fitted into an inner peripheral surface of the pulley member, and a second clutch configured by an outer peripheral surface of the annular member in the clutch inner ring region. The pulley unit with a built-in clutch according to any one of claims 1 to 5, wherein the pulley unit is incorporated in a clutch space formed between the clutch raceway and the clutch raceway.

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