JP4465966B2 - Pulley device with built-in roller clutch for alternator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  A pulley device with a built-in roller clutch for an alternator that is an object of the present invention is fixed to an end of a rotating shaft of an alternator, which is a generator for an automobile, and between a driving pulley fixed to an end of an engine crankshaft. It is used to drive the alternator by hanging an endless belt. In particular, the present invention provides a case where a so-called poly V belt in which a plurality of ridges each having a V-shaped cross section are continuously provided over the entire circumference is used as the endless belt. A useful structure is realized.
[0002]
[Prior art]
  Japanese Unexamined Patent Publication No. 7-139550 discloses a structure of an alternator that generates electric power necessary for an automobile using an automobile driving engine as a drive source. FIG. 5 shows the alternator 1 described in this publication. A rotating shaft 3 is rotatably supported by a pair of rolling bearings 4 and 4 inside the housing 2. A rotor 5 and a commutator 6 are provided at an intermediate portion of the rotating shaft 3. Further, a pulley 7 is fixed to a portion protruding from the housing 2 at one end portion (right end portion in FIG. 5) of the rotating shaft 3. In an assembled state to the engine, an endless belt is stretched over the pulley 7 so that the rotary shaft 3 can be driven to rotate by the crankshaft of the engine.
[0003]
  Conventionally, as the pulley 7, a pulley that is simply fixed to the rotating shaft 3 has been used. On the other hand, in recent years, when the traveling speed of the endless belt is constant or increasing, it is possible to freely transmit power from the endless belt to the rotating shaft, and when the traveling speed of the endless belt is decreasing, Various types of pulley devices with built-in roller clutches for alternators that allow relative rotation between the pulley and the rotating shaft have been proposed and used in part. For example, JP-A-56-101353, JP-A-7-317807, JP-A-8-61443, JP-A-8-226462, JP-B-7-72585, French patent publication FR27226059A1, etc. An alternator roller clutch built-in type pulley apparatus having various functions is described. In some cases, such a pulley device with a built-in roller clutch for an alternator is actually used.
[0004]
  FIG. 6 shows a pulley apparatus with a built-in roller clutch for an alternator described in JP-A-8-226462. This pulley device with a built-in roller clutch for an alternator has a sleeve 8 that can be externally fitted and fixed to the rotating shaft 3 of the alternator 1 (FIG. 5). A pulley 7 a is arranged around the sleeve 8 so as to be concentric with the sleeve 8. On the outer peripheral surface of the pulley 7a, a plurality of concave grooves 29, 29 each having a V-shaped cross section that are continuous over the entire circumference are formed in parallel with each other in the axial direction (left-right direction in FIG. 6). An endless belt called a so-called poly V belt, in which a plurality of protrusions each having a V-shaped cross section are continuously provided over the entire circumference, is stretched over the pulley 7a.
[0005]
  A pair of support bearings 9 and 9 and a roller clutch 10 are provided between the outer peripheral surface of the sleeve 8 and the inner peripheral surface of the pulley 7a. Of these, the support bearings 9 and 9 support the radial load applied to the pulley 7a while allowing the sleeve 8 and the pulley 7a to rotate relative to each other. The roller clutch 10 can freely transmit the rotational force from the pulley 7a to the sleeve 8 only when the pulley 7a tends to rotate relative to the sleeve 8 in a predetermined direction. In the case of the structure shown in FIG. 6, each of the support bearings 9 and 9 is a cylindrical roller bearing. However, a structure in which an angular type or deep groove type ball bearing is used as the support bearing is also available, for example, in the above-mentioned JP-A-7-317807. As described in the publication, it is conventionally known.
[0006]
  A plurality of recesses 25 called ramp portions are formed at equal intervals in the circumferential direction on the outer peripheral surface of the inner ring 24 that constitutes the roller clutch 10 and is externally fitted and fixed to the sleeve 8. A cam surface 26 is formed on the outer peripheral surface of the intermediate portion. The outer peripheral surfaces of both ends of the inner ring 24 are inner ring raceways 27 and 27 for the support bearings 9 and 9, respectively. On the other hand, the inner peripheral surface of the outer ring 12 that constitutes the roller clutch 10 and is externally fitted and fixed to the pulley 7a is a simple cylindrical surface over almost the entire length. A plurality of rollers 11 and 11 constituting the roller clutch 10 together with the inner ring 24 and the outer ring 12 are supported by the cage 28 so as to be able to be slightly displaced in the rolling and circumferential directions. And the spring is provided between the pillar part provided in this holder | retainer 28, and each said roller 11, and these each roller 11 is elastically pressed in the same direction regarding the circumferential direction.
[0007]
  The reason why the above-described pulley device with a built-in roller clutch for an ornator is used is as follows. For example, when the driving engine is a diesel engine, the fluctuation of the rotational angular speed of the crankshaft becomes large at low speeds such as idling. As a result, the traveling speed of an endless belt (not shown) that is stretched over a drive pulley fixed to the end of the crankshaft also varies finely. On the other hand, the rotating shaft 3 of the alternator 1 that is rotationally driven by the endless belt via the pulley 7a has an inertial mass such as the rotating shaft 3, the rotor 5 fixed to the rotating shaft 3, and the commutator 6 (FIG. 5). Based on this, it does not change so rapidly. Therefore, when the pulley 7a is simply fixed to the rotary shaft 3, the endless belt and the pulley 7a tend to rub against each other as the rotational angular velocity of the crankshaft varies. As a result, stress in different directions is repeatedly applied to the endless belt that rubs against the pulley 7a, and slippage is likely to occur between the endless belt and the pulley 7a, or the life of the endless belt is shortened. Cause it.
[0008]
  In addition, the life reduction of the endless belt based on the friction between the outer peripheral surface of the pulley 7a and the inner peripheral surface of the endless belt as described above is also caused by repeated acceleration / deceleration during traveling. That is, while driving force is transmitted from the endless belt side to the pulley 7a side during acceleration, braking force is applied from the endless belt to the pulley 7a that continues to rotate based on inertia as described above during deceleration. To do. The braking force and the driving force act as frictional forces in the opposite direction against the inner peripheral surface of the endless belt, and thus cause a decrease in the life of the endless belt. In particular, in the case of a vehicle equipped with an exhaust brake such as a truck, the deceleration of the decrease in rotation of the crankshaft when the accelerator is off is significant, and the frictional force applied to the inner peripheral surface of the endless belt based on the braking force As a result, the above-mentioned decrease in life is remarkable.
[0009]
  Therefore, by using the alternator roller clutch built-in type pulley device as the pulley 7a as described above, when the traveling speed of the endless belt tends to be constant or rising, the pulley 7a is connected to the rotating shaft 3. When the traveling speed of the endless belt tends to decrease, the pulley 7a and the rotating shaft 3 can be freely rotated relative to each other. That is, when the traveling speed of the endless belt tends to decrease, the rotational angular speed of the pulley 7a is made slower than the rotational angular speed of the rotating shaft 3, and the contact portion between the endless belt and the pulley 7a is strong. Prevent rubbing. In this way, the direction of the stress acting on the rubbing portion between the pulley 7a and the endless belt is made constant, slippage occurs between the endless belt and the pulley 7a, or the life of the endless belt is reduced. To prevent it.
[0010]
[Problems to be solved by the invention]
  The first object of the present invention is to prevent displacement of the roller clutch retainer in the axial direction, and the rollers held by the retainer are connected to the outer peripheral surface of the roller clutch inner ring and the inner periphery of the roller clutch outer ring. The point is to prevent it from coming off the surface.
[0011]
  The second object is to prevent the roller clutch retainer from rubbing so as to be stretched between the outer ring and the inner ring for the support bearing that rotate relative to each other, thereby increasing the rotational resistance of the support bearing. It is in.
[0012]
[Means for Solving the Problems]
  Pulley with built-in roller clutch for alternator of the present inventionConventional equipmentLike a known pulley device with a built-in roller clutch for an alternator, a sleeve that can be externally fixed to the rotating shaft of the alternator, and a sleeve that is concentrically arranged around the sleeve, and each of the outer circumferential surfaces of the sleeve is arranged around the entire circumference. A pulley having a plurality of V-shaped concave grooves that extend continuously in parallel with each other in the axial direction, and between the axial intermediate portion of the outer peripheral surface of the sleeve and the axial intermediate portion of the inner peripheral surface of the pulley. And a roller clutch that allows transmission of rotational force between the pulley and the sleeve only when the pulley tends to rotate relative to the sleeve in a predetermined direction. Provided between the outer peripheral surface of the sleeve and the inner peripheral surface of the pulley at the pinched position, and the radial load applied to the pulley is supported while the sleeve and the pulley can rotate freely. And a pair of support bearings.
[0013]
  In particular, the roller clutch built-in type for the alternator of the present inventionIn the pulley apparatus, the pulley has an inner diameter that does not change over the entire length in the axial direction. The both support bearings are ball bearings having a support bearing inner ring separate from the sleeve and a support bearing outer ring separate from the pulley. Further, the roller clutch has a roller clutch inner ring separate from the sleeve and a roller clutch outer ring separate from the pulley. And this inner ring for roller clutchThe outer diameter of the roller clutch and the inner diameter of the roller clutch cage areInner ring for support bearingSmaller than the outer diameter of
  Further, in the pulley device with a built-in roller clutch for an alternator according to claim 2,In addition to the constituent elements of the pulley device with a built-in roller clutch for an alternator described in claim 1, the inner diameter of the outer ring for roller clutch is made larger than the inner diameter of the outer ring for both support bearings. and,Outside diameter of the roller clutch cageTheThan the inner diameter of the outer ring that constitutes the support bearingSmall.
[0014]
[Action]
  In the case of the pulley device with a built-in roller clutch for an alternator according to the present invention configured as described above, displacement of the roller clutch retainer in the axial direction is prevented, and the roller retained by the retainer is the roller clutch. The outer ring of the inner ring and the inner ring of the roller clutchCan be prevented.
  Furthermore, in the case of the pulley device with a built-in roller clutch for an alternator according to claim 2, in addition to the above-mentioned action and effect,The roller clutch cage is rubbed over the outer ring and inner ring for the support bearings that rotate relative to each other to increase the rotational resistance of the support bearings.Can be prevented.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
  FIG. 1 shows a first example of an embodiment of the present invention. The sleeve 8 is formed in a cylindrical shape as a whole, and is fitted around and fixed to the end of the rotating shaft 3 (see FIGS. 5 to 6) of the alternator, and is rotatable with the rotating shaft 3. Therefore, in the illustrated example, a female spline portion 13 is formed on the inner peripheral surface of the intermediate portion of the sleeve 8, and a male spline portion (not shown) formed on the female spline portion 13 and the outer peripheral surface of the end portion of the rotary shaft 3. Can be freely engaged. The structure for preventing the relative rotation between the rotating shaft 3 and the sleeve 8 is not a spline, but a screw or a non-cylindrical surface as shown in FIG. And so on.
[0016]
  A pulley 7 a is arranged around the sleeve 8 as described above concentrically with the sleeve 8. The pulley 7a is equipped with support bearings 9a and 9a and a roller clutch 10a, which will be described below, on the inner side. Also, on the outer peripheral surface of the pulley 7a, a plurality of concave grooves 29, 29 each having a V-shaped cross section are formed over the entire circumference, and the cross-sectional shape extending in the width direction is corrugated and is called a poly V belt. A part of the endless belt can be passed freely.
[0017]
  A pair of support bearings 9a and 9a and one roller clutch 10a are provided between the outer peripheral surface of the sleeve 8 configured as described above and the inner peripheral surface of the pulley 7a. Of these, the support bearings 9a and 9a allow a relative rotation between the sleeve 8 and the pulley 7a while supporting a radial load applied to the pulley 7a. In the illustrated example, deep groove ball bearings are used as the support bearings 9a and 9a. That is, each of these support bearings 9a and 9a has deep groove type outer ring raceways 14 and 14 on the inner peripheral surface, respectively.For support bearingThe outer rings 15 and 15 have deep groove type inner ring raceways 16 and 16 on their outer peripheral surfaces.For support bearingInner rings 17, 17 and a plurality of rolling elements (balls) 18, 18 provided between the outer ring raceways 14, 14 and the inner ring raceways 16, 16 respectively so as to be freely rollable. Such support bearings 9a, 9a are respectivelyFor support bearingThe outer rings 15 and 15 are fitted and fixed to both ends of the inner peripheral surface of the pulley 7a by interference fitting.For support bearingThe inner rings 17 are provided between the outer peripheral surface both ends of the sleeve 8 and the inner peripheral surface both ends of the pulley 7a by being fitted and fixed to both ends of the outer peripheral surface of the sleeve 8 by interference fitting.
[0018]
  Further, the roller clutch 10a can freely transmit the rotational force between the pulley 7a and the sleeve 8 only when the pulley 7a tends to rotate in a predetermined direction with respect to the sleeve 8. In order to constitute such a roller clutch 10a, an inner ring 19 for roller clutch is fitted and fixed to the outer peripheral surface of the intermediate portion of the sleeve 8 by an interference fit. The inner ring 19 for roller clutch is formed in a cylindrical shape as a whole by a hard metal such as bearing steel, and a cam surface 20 is formed on the outer peripheral surface. That is, a plurality of concave portions 21 called ramp portions are formed at equal intervals in the circumferential direction on the outer peripheral surface of the roller clutch inner ring 19, and the cam surface 20 is formed on the outer peripheral surface. On the other hand, the inner peripheral surface of the roller clutch outer ring 22 is a simple cylindrical surface. A plurality of rollers 11a constituting the roller clutch 10a together with the roller clutch inner ring 19 and the roller clutch outer ring 22 are externally fitted to the roller clutch inner ring 19 so that the rotation with respect to the roller clutch inner ring 19 is impossible. The cage 23 made of synthetic resin is supported so as to be slightly displaceable in the rolling and circumferential directions. An elastic material such as a spring is provided between the column portion provided on the cage 23 and each roller 11a, and the rollers 11a are elastically pressed in the same direction with respect to the circumferential direction. . Since the structure and operation of the roller clutch are conventionally known, detailed illustration and description are omitted.
[0019]
  In particular, in the case of the pulley device with a built-in roller clutch for the alternator of this example, the diameter D of the plurality of rollers 11a constituting the roller clutch 10a._a Is made larger than that of the conventional structure. That is, the diameter D of each of these rollers 11a_a And the diameter D of the inner peripheral surface of the outer ring 22 for roller clutch_o Ratio D_a / D_o , A value exceeding 0.070 (D_a / D_o > 0.070). For example, in the illustrated example, the ratio D_a / D_o Is set to 0.14.
[0020]
  In the case of the pulley device with a built-in roller clutch for an alternator of the present example configured as described above, the rotation speed of the pulley 7a over which an endless belt is stretched is applied to the rotating shaft 3 of the alternator by the action of the roller clutch 10a. Torque is transmitted from the pulley 7a to the rotary shaft 3 only when the rotational speed of the fixed sleeve 8 is higher than the rotational speed. In other words, when the rotational speed of the pulley 7a is lower than the rotational speed of the sleeve 8, the pulley 7a and the sleeve 8 are disconnected from each other to prevent an excessive force from being applied to the endless belt.
[0021]
  In particular, in the case of the pulley device with a built-in roller clutch for the alternator of this example, the diameter D of the plurality of rollers 11a constituting the roller clutch 10a._a The diameter D of the inner peripheral surface of the outer ring 22 for roller clutch constituting the roller clutch 10a_o Therefore, the torque capacity of the roller clutch 10a can be sufficiently increased. For this reason, sufficient durability can be ensured even in a use state where the tension of the endless belt stretched over the pulley 7a is increased and the torque transmitted by the roller clutch 10a is increased.
[0022]
  The pulley device with a built-in roller clutch for the alternator of this example has a diameter D of each roller 11a._a And the diameter D of the inner peripheral surface of the roller clutch outer ring 22_o Ratio D_a / D_o The reason why the value exceeds 0.070 is as follows.
  When the endless belt shifts from the deceleration state to the acceleration state, the rollers 11a constituting the roller clutch 10a are pushed by a spring provided between the pillars of the retainer 23 and the inner ring for the roller clutch. Of the gap between the outer peripheral surface of 19 and the inner peripheral surface of the outer ring 22 for roller clutch, a portion that has a narrow width in the diametrical direction bites into a wedge shape. The force with which the spring presses each roller 11a is, for example, as small as 1 kgf or less, and the outer diameter of the rotating shaft 3 (FIGS. 5 to 6) is about 15 to 20 mm. In the case of a pulley device with a built-in roller clutch, the length of space (roller 11a) required to hold the rollers 11a displaceably in the circumferential direction so as to switch the roller clutch 10a between a locked state and an overrun state. The circumferential length W, which is the sum of the space length required to provide the column and the spring, is the following regardless of the diameter of each roller 11a. A substantially constant value (W) expressed by equation (1) is required. In this equation (1), D_i Is the diameter of the portion of the outer peripheral surface of the roller clutch inner ring 19 that comes into contact with the rolling surface of each of the rollers 11a._i ≒ D_o -2D_a It is. Z is the number of the rollers 11a.
[0023]
  π ・ (D_i + D_a ) / Z = D_a + W --- (1)
  Further, the maximum value P of the contact surface pressure between the rolling surface of each roller 11a and the outer peripheral surface of the roller clutch inner ring 19 and the inner peripheral surface of the roller clutch outer ring 22 is shown._max Becomes the following equation (2). In this equation (2), E is the longitudinal elastic modulus (kgf / mm² ), M is the Poisson number, Σρ is the sum of the curvatures of a pair of cylindrical surfaces in contact with each other (mm)^-1), Q_max Is the maximum load (kgf) in the normal direction applied to both cylindrical surfaces, L_a Is the contact length between these two cylindrical surfaces.
  P_max
    = [{E / π / (1-1 / m² )} ・ (Σρ / 2) ・ Q_max / L_a ]^1/2
                                                        ---- (2)
[0024]
  In order to ensure the durability of the roller clutch 10a, when the roller clutch 10a is locked, cracks occur in the outer peripheral surface of the roller clutch inner ring 19 where a larger surface pressure is applied than the inner peripheral surface of the roller clutch outer ring 22. In order to prevent damage such as cracks), the maximum value P of the load applied in the normal direction to the roller clutch inner ring 19 and the outer peripheral surface of each of the rollers 11a._max 250-320kgf / mm² It is necessary to keep it below a certain value determined within the range. Contact length L between the outer peripheral surface of the roller clutch inner ring 19 and the outer peripheral surface of each roller 11a._a Is constant, the maximum value P_max Is constant, the maximum value Q of the load in the normal direction applied to the contact part between these two peripheral surfaces_max Is
  Q_max ∝1 / Σρ ---- (3)
It becomes.
  Further, the diameter D of each roller 11a._a Since the radius of curvature of the cam surface 20 with which the outer peripheral surface of each roller 11a abuts is much larger than 1 / Σρ,_a Can be approximated by / 2. Therefore, the following equation (4) is derived from the above equation (3).
  Q_max ∝D_a   ---- (4)
[0025]
  Next, the torque capacity T of the roller clutch 10a will be described with reference to FIG. This torque capacity T is expressed by the following equation (5). In this equation (5), F is the force with which the inner peripheral surface of the cam surface 20 and the outer ring 22 for roller clutch presses the rolling surface of each roller 11a when locked, and α is the rolling force of each roller 11a. The contact angle between the surface and the cam surface 20 is a constant value determined in the range of 4 to 5 degrees in order to realize the locked state of the roller clutch 10a. Β is an intersection angle between a load vector acting on each roller 11 a and a straight line connecting the rolling surface of each roller 11 a and the rotation center of the cam surface 20.
  T = F ・ sin β ・ Z ・ D_i / 2 ---- (5)
  F ・ cosα = Q_max                 --- (6)
Substituting equation (6) into equation (5) and deleting F,
  T = Z ・ Q_max ・ D_i ・ (Sinβ / cosα) / 2 ---- (7)
  It is a triangle connecting three points of contact points A and B between the cam surface 20 and the inner peripheral surface of the roller clutch outer ring 22 and the rolling surface of each roller 11 a and the center point O of the roller clutch outer ring 22. Applying the sine theorem to a certain AOB,
  sin β / (D₀ / 2) = sin α / (D_i / 2) ---- (8)
Substituting equation (8) into equation (7) to eliminate sin β,
  T = Z ・ Q_max ・ D_i ・ (1 / cos α) ・ (D₀ / D_i ) ・ (Sin α / 2)
    = ZQ_max ・ D₀ ・ Tan α / 2 ---- (9)
  Where Q_max ∝D_a , D_a = (D_i When π−Z · W) / (Z−π) is substituted into equation (9) and tanα is constant,
  T Ｚ Z ・ D_a ・ D₀ ∝Z ・ {(D_i .Pi.-Z.W) / (Z-.pi.)}. D₀
                                              --- (10)
  Here, when the second cosine theorem is used in the ΔAOB,
   cosα = {(D₀ / 2)² + D_a ² ・ Cos²α- (D_i / 2)² }
/ {(D₀ / 2) ・ D_a cos α} ---- (11)
This equation (11) is converted to D₀ When you solve it,
  D₀ = 2D_a ・ Cos²α + √ (D_i ² + 4D_a ² ・ Cos^Fourα-4D_a ² ・ Cos²α)
                                      --- (12)
Substituting this equation (12) into equation (10) above,
  T ∝ Z ・ {(D_i .Pi.-Z.W) / (Z-.pi.)}. {2D_a ・ Cos²α + √ (D_i ² + 4D_a ² ・ Cos^Fourα-4D_a ² ・ Cos²α)} ---- (13)
[0026]
  In the case of a pulley apparatus with a built-in roller clutch for an alternator of an automobile, the outer diameter of the rotating shaft 3 (FIG. 5) of the alternator 1 is added with a thickness necessary for strength as a sleeve 8 and an inner ring 19 for a roller clutch. Outer diameter D of roller clutch inner ring 19_i The value is about 28 to 38 mm. Further, in order to repeatedly realize the locked state and the overrun state, the space length required for holding each roller 11a so as to be displaceable in the circumferential direction and the space length required for providing the column portion and the spring are as follows. The total circumferential length W is about 2 to 3 mm. If the circumferential length W can be reduced, many rollers 11a can be incorporated, and the torque capacity of the roller clutch 10a can be increased. However, the contact angle α for realizing the locked state of the roller clutch 10a is a small value of about 4 to 5 degrees as described above. For this reason, even when the diameter dimension of the cam surface 20 formed on the outer peripheral surface of the roller clutch inner ring 19 is slightly changed, the circumferential position of each roller 11a is large when the roller clutch 10a is locked. fluctuate. Considering this, it is difficult to make the circumferential length W too small. And if such a thing is considered, this circumferential direction length W will need about 2-3 mm.
[0027]
  Therefore, the outer diameter D of the roller clutch inner ring 19_i And various values of the circumferential length W, a value proportional to the torque capacity of the roller clutch 10a is calculated by the above equation (13), and the ratio D and the value proportional to the calculated torque capacity are calculated._a / D_o The relationship is shown in FIG. As is apparent from FIG. 3, in any case, the diameter D of the roller_a And the diameter D of the inner peripheral surface of the roller clutch outer ring 22_o Ratio D_a / D_o Increases as the torque capacity of the roller clutch 10a increases. And the ratio D, which has been used conventionally_a / D_o This ratio D as in the present invention, compared with a value of about 0.05 to 0.07_a / D_o When the value exceeds 0.07, it can be seen that a large capacity can be obtained.
[0028]
  Furthermore, in the case of the present invention, the outer diameter of the roller clutch inner ring 19 is configured to constitute the support bearings 9a, 9a.For support bearingIt is smaller than the outer diameter of the inner rings 17. Accordingly, the outer peripheral surface of the roller clutch inner ring 19 isFor each of the above support bearingsThe inner rings 17 are recessed inward in the diameter direction from the outer peripheral surfaces of the inner rings 17. The inner diameter of the cage 23 constituting the roller clutch 10a (the diameters of the inscribed circles of the plurality of convex portions formed on the inner peripheral edge of the cage 23 to be engaged with the concave portions 21) is Larger than the outer diameter of the inner ring 19 for the roller clutch,For each of the above support bearingsIt is smaller than the outer diameter of the inner rings 17. Therefore, the end portions closer to the inner diameter of the both axial sides of the cage 23 are respectivelyFor support bearingOpposing to the axial end surfaces of the inner rings 17, 17, the cage 23 isFor each of these support bearingsDisplacement in the axial direction (left and right direction in FIG. 1) is prevented by the inner rings 17 and 17. Therefore, the rollers 11 a held by the retainer 23 are not separated from the outer peripheral surface of the roller clutch inner ring 19 and the inner peripheral surface of the roller clutch outer ring 22. Accordingly, there is no need to perform troublesome processing on the inner ring 19 for roller clutch and the outer ring 22 for roller clutch, which are each made of hard metal such as bearing steel, which constitute the roller clutch 10a. Cost reduction.
[0029]
  At the same time, in the case of the present invention, the outer diameter of the cage 23 is configured to form the support bearings 9a and 9a.For support bearingIt is smaller than the inner diameter of the outer rings 15 and 15. Therefore, the end closer to the inner diameter of one side surface of the cage 23 in the axial direction isFor any support bearingEven when it hits the end surface of the inner ring 17, the end portion closer to the outer diameter of the one side surface of the cage 23 in the axial direction is the above.For any support bearingThere is no contact with the end face of the outer ring 15. For this reason, the cage 23 rotates relatively.For support bearingWith outer ring 15For support bearingIt does not increase the rotational resistance of the support bearing 9a by rubbing so as to be stretched over the inner ring 17.
[0030]
  The cage 23 isNot always around the whole circumferenceFor each of the above support bearingsIt is not necessary to engage with the axial end surfaces of the inner rings 17 and 17. A part of the circumferential direction protrudes in the diameter direction, and this protruding part isFor each of the above support bearingsYou may make it engage with the axial direction end surface of the inner rings 17 and 17.
[0031]
  Next, FIG. 4 shows a second example of the embodiment of the present invention. In the case of this example, the roller clutch outer ring 22a is formed to be wide, and support bearings 9a and 9a are formed at both ends of the roller clutch outer ring 22a, respectively.For support bearingThe outer rings 15 and 15 are fitted and fixed. In the case of such a structure, before assembling the pair of support bearings 9a, 9a and the roller clutch 10a between the inner peripheral surface of the pulley 7a and the outer peripheral surface of the sleeve 8, as a non-separable unit. Since it can be handled, the assembly workability of the pulley device with a built-in roller clutch for the alternator can be improved. Also in this example, the diameter D of the roller 11a_a And the diameter D of the inner peripheral surface of the intermediate portion of the outer ring 22a for the roller clutch_o Ratio D_a / D_o Is about 0.12 and a value exceeding 0.07 to secure the torque capacity of the roller clutch 10a. Other configurations and operations are the same as those of the first example described above.
[0032]
【The invention's effect】
  Since the pulley device with a built-in roller clutch for an alternator according to the present invention is configured and operates as described above, displacement of the roller clutch retainer in the axial direction is prevented, and the roller retained by the retainer is It is possible to prevent the roller clutch inner ring from being detached from the outer peripheral surface of the roller clutch outer ring and the inner peripheral surface of the roller clutch outer ring. or,If necessary,It is possible to prevent the roller clutch retainer from being rubbed so as to be stretched between the outer ring and the inner ring for the support bearing that rotate relative to each other, thereby increasing the rotational resistance of the support bearing.
[Brief description of the drawings]
FIG. 1 is a half sectional view showing a first example of an embodiment of the present invention.
FIG. 2 is a schematic view corresponding to the XX section of FIG. 1 for explaining the torque capacity of the roller clutch.
FIG. 3 is a diagram showing the influence of the ratio of the diameter of the roller and the diameter of the inner peripheral surface of the outer ring for roller clutch on the torque capacity of the roller clutch.
FIG. 4 is a half sectional view showing a second example of an embodiment of the present invention.
FIG. 5 is a sectional view showing an example of a conventionally known alternator.
FIG. 6 is a partial cross-sectional view showing an example of the structure of a conventionally known pulley device with a built-in roller clutch for an alternator.
[Explanation of symbols]
    1 Alternator
    2 Housing
    3 Rotating shaft
    4 Rolling bearing
    5 Rotor
    6 Commutator
    7, 7a Pulley
    8 sleeve
    9, 9a Support bearing
  10, 10a Roller clutch
  11, 11a Roller
  12 Outer ring
  13 Female spline part
  14 Outer ring raceway
  15For support bearingOuter ring
  16 Inner ring raceway
  17For support bearingInner ring
  18 Rolling elements
  19 Inner ring for roller clutch
  20 Cam surface
  21 recess
  22, 22a Outer ring for roller clutch
  23 Cage
  24 inner ring
  25 recess
  26 Cam surface
  27 Inner ring raceway
  28 Cage
  29 Groove

Claims (2)

A sleeve that can be fitted and fixed to the rotation shaft of the alternator, and a concentric arrangement with the sleeve around the sleeve, and a plurality of V-shaped concave grooves that are continuous over the entire circumference on the outer periphery of the sleeve. Between the pulley formed in parallel with each other and the axial intermediate portion of the outer peripheral surface of the sleeve and the axial intermediate portion of the inner peripheral surface of the pulley, and the pulley rotates relative to the sleeve in a predetermined direction. A roller clutch that allows the transmission of rotational force between the pulley and the sleeve only when the tendency is present, and the outer peripheral surface of the sleeve and the inner peripheral surface of the pulley at a position sandwiching the roller clutch from both sides in the axial direction. Built-in roller clutch for alternator with a pair of support bearings that support the radial load applied to the pulley and allow the sleeve and pulley to rotate relative to each other. In pulley unit, the pulley, which inner diameter does not change over the entire length in the axial direction, the both support bearings, separate from the support inner and the pulley bearing separate from the said sleeve a ball bearing having a support outer ring bearing body, the roller clutch, the said sleeve has a roller outer ring clutch separate the roller clutch inner race and a separate body from the aforementioned pulley, an inner ring for this roller clutch A roller device with a built-in roller clutch for an alternator, wherein the outer diameter of the roller clutch and the inner diameter of the cage of the roller clutch are smaller than the outer diameter of the inner ring for support bearing . Large inner diameter of the outer ring roller clutch than the inner diameter of the outer ring for two support bearings, and the outer diameter dimension of the cage of the roller clutch is smaller than the inner diameter of the outer ring for the both support bearings, according to claim 1 alternator roller clutch built-in type pulley apparatus.

Images