JP2018105497A - Pulley with isolation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulley with isolation capable of improving durability.SOLUTION: A pulley P with isolation includes a hub 10 having a boss fixed to a rotating shaft and a radial direction part 12; and a pulley main body 20 having a pulley part 21 to which a belt is installed and a cover part 22 opposing against the radial direction part 12. An isolator rubber 26 is arranged between the radial direction part 12 and the cover part 22 and a coupling rubber 34 is arranged between the other end part of the pulley part 21 and an outside part of the radial direction part 12. An engagement ring 33 fixed to the coupling rubber 34 is engaged with the hub 10 by a protrusion 35 when a deformation stroke of the isolator rubber 26 becomes a specified value and an excessive elastic deformation of the isolator rubber 26 is prevented by the coupling rubber 34.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an isolation pulley that transmits a driving force of a driving-side rotating shaft to a driven-side rotating shaft via a belt while insulating a torque fluctuation caused by an explosion stroke during engine operation.

  In an internal combustion engine mounted on a vehicle or the like, that is, an engine, a pulley is used to transmit a driving force of a crankshaft to main shafts of various auxiliary machines such as a generator and a compressor via a belt such as a V belt. It is attached to each of the crankshaft and the main shafts of auxiliary machinery. An endless belt is stretched around the outer periphery of both pulleys, the pulley mounted on the crankshaft, which is the rotating shaft, is on the drive side, and the pulley mounted on the main shaft, which is the rotating shaft, is on the driven side. Become.

  In recent years, for the purpose of improving fuel efficiency, an increasing number of vehicles have an idling stop function that stops an engine when the vehicle stops for a short time by a signal or the like and then restarts the engine (hot start). Some of these engines also use a generator (alternator), which is a generator, as a motor. Sometimes called. Hereinafter, in this specification, the ISG system is referred to as a unified term. In this ISG type idling stop mechanism, electric power is applied from the battery to the generator when the engine is restarted to cause the generator to function as a starter motor. The driving force of the starter motor is transmitted to the crankshaft via the belt, and the engine is started. Hereinafter, a generator that can function as a motor is referred to as a motor generator. In this case, the main shaft of the motor generator is on the drive side, and the crankshaft of the engine is on the driven side.

  Furthermore, there is an ISG hybrid vehicle that reinforces the motor generator used only for engine restart (hot start) and assists the driving force of the engine.

  In this ISG hybrid vehicle, when the crankshaft is driven by the engine, the motor generator is driven with the crankshaft to which the driving force is applied by the engine as the drive side, and when the crankshaft is driven by the motor generator, The crankshaft is driven with the motor generator to which power is applied from the battery as the drive side. When the main shaft of the motor generator is used as a drive source, the torque of the motor generator can be added to the engine torque to assist the crankshaft, or the engine can be started.

  When a belt is used to transmit the driving force of the engine crankshaft to the accessories, pulleys are attached to the crankshaft and the main shafts of the accessories. As described in Patent Documents 1 to 3, this pulley transmits drive torque from the crankshaft to the main shafts of the auxiliary machinery, and at the same time, reduces vibration caused by resonance of the natural value of the engine. A pulley having a damper function that insulates crankshaft torque fluctuations caused by the above is used. These pulleys include a hub attached to a rotating shaft, and a pulley body provided with a pulley portion around which a belt is stretched. An annular mass body, that is, an inertia ring, and an annular mass body are provided inside the pulley portion. A dynamic damper composed of an annular damper rubber and the above-mentioned annular mass body is arranged between the inner peripheral surface and the large diameter portion of the hub, and this dynamic damper reduces vibrations caused by resonance of the natural value of the engine. Is done. In addition, these pulleys have an isolation rubber disposed between the hub and the pulley body, and transmit the rotational force of the crankshaft from the rotation shaft to the pulley body, while the torque fluctuation of the crankshaft is caused by the elasticity of the isolation rubber. Is insulated. That is, the isolation rubber transmits the rotational force of the crankshaft to the pulley body, but the torque fluctuation (rotation unevenness) superimposed on the crankshaft is absorbed by the elasticity of the isolation rubber and is not transmitted to the pulley body. That is, it is insulated.

JP 2006-17234 A JP 2007-71263 A JP 2008-57553 A

  In the pulley described in Patent Document 1, a rubber coupling portion extending in the radial direction is provided between both axial ends of the pulley portion and the hub. In the pulley described in Patent Document 2, in addition to the damper rubber, a coupling rubber is provided between the coupling cylinder portion having a smaller diameter than the pulley portion and the hub. These coupling parts and coupling rubbers transmit the input torque transmitted to the hub by the shear deformation in the circumferential direction to the pulley part while smoothing it. Further, in the pulley described in Patent Document 3, a cylindrical elastic body extending in the axial direction is attached as an isolator rubber between a radial cover portion integrated with the pulley portion and a radial portion of the hub. ing. This cylindrical elastic body blocks the rotational fluctuation so that the torque fluctuation of the rotating shaft is not transmitted to the pulley portion.

  In the pulley as described above, when the torque difference between the hub and the pulley portion is large, the hub and the pulley main body are greatly displaced in the circumferential direction, and at this time, the isolator rubber is greatly deformed in the circumferential direction. When absorbing torque fluctuations due to the shear deformation of the isolator rubber, if an excessive torque is applied, the isolator rubber may break and the pulley may fall off. For this reason, in the normal use range, the spring constant of the isolator rubber is set so that the displacement amount between the hub and the pulley main body becomes a certain value or less. An engagement mechanism is provided so that power transmission is not interrupted in the short term even when the displacement exceeds a certain value due to abnormal vibration or the like and the isolator rubber is broken. As an engagement mechanism, there is a mechanism in which an arc-shaped long hole extending in the circumferential direction is provided in the pulley body, and a protrusion protruding from the long hole is provided in the hub.

  In addition, as described above, in the normal use range, the protrusion is designed not to contact the end face of the long hole of the hub, but before the deformation limit of the isolator rubber, so that the isolator rubber does not break even during abnormal vibration. In some cases, the protrusion provided on the hub contacts the elongated hole of the pulley body to prevent destruction of the isolator rubber.

  In this case, the deformation stroke of the isolator rubber, that is, the stroke until the protrusion provided on the hub comes into contact with the long hole of the pulley body cannot be made large. Contact is likely to occur. This contact not only generates a large impact sound and makes the driver feel uneasy, but when this contact is repeated, metal wear powder is generated from the contact portion. When the generated wear powder enters the sliding portion inside the pulley, the sliding portion is worn and affects the life of the pulley, which may reduce the durability of the pulley. In an automobile engine, the crankshaft rotation speed is designed to pass through a low-order resonance point before reaching the normal operating rotation range. Therefore, a relatively large torsional vibration occurs at this resonance point when the engine is started. Therefore, at this time, the above-described contact may occur.

  In particular, when the above pulley is used in a vehicle having an ISG type idling stop function for starting a crankshaft by a motor generator or a vehicle of an ISG type hybrid system, it is connected to the motor generator every time the engine is started. Since the driving force is transmitted from the pulley side to the hub connected to the crankshaft, the isolator rubber of the pulley is repeatedly deformed to the maximum circumferential displacement, so in the pulleys used in these systems, Depending on the situation of use, periodic replacement is required, and improvement in durability is strongly desired.

  On the other hand, in order to prevent the protrusion provided on the hub from impactingly contacting the long hole provided in the pulley, it is conceivable to place a cushion rubber between the inner wall surface of the long hole and the protrusion. In that case, since it is necessary to withstand the contact that occurs each time the motor generator is driven, a soft cushion rubber cannot be used, and the shock absorbing force is insufficient. In addition, since hard cushion rubber is likely to generate rubber wear powder due to the impact of the protrusions, if this rubber wear powder enters the sliding portion, the durability of the pulley may be reduced.

  The objective of this invention is providing the pulley with an isolation which can improve durability.

  The pulley with isolation of the present invention includes a mounting portion attached to the rotating shaft, a hub including a radial portion integrally extending to the mounting portion and extending radially outward, a pulley portion to which a belt is attached, And a pulley body including a cover portion extending radially inward from one end portion in the axial direction of the pulley portion and facing the radial direction portion, and an isolator rubber disposed between the radial direction portion and the cover portion An engagement ring is attached, and an annular coupling rubber disposed between the other axial end portion of the pulley portion and the radial direction portion, and the hub or the pulley portion and the engagement ring. An engagement mechanism that is capable of engaging the engagement ring and the hub or the pulley portion, and the engagement mechanism is disengaged by a twist angle of the hub with respect to the pulley body. State and engagement And it can be switched between a state.

  An isolator rubber is disposed between the hub and the pulley body, and a driving force is transmitted between the hub and the pulley. At the same time, torque fluctuation of the hub is insulated by the isolator rubber and is not transmitted to the pulley. When the deformation stroke of the isolator rubber becomes a certain value or more due to the displacement of the hub and the pulley body in the circumferential direction, the coupling rubber is elastically deformed via the engagement ring by the engagement mechanism. That is, when the circumferential displacement between the hub and the pulley main body is a certain value or less, the isolator rubber works alone, and when it is more than a certain value, the isolator rubber and the coupling rubber cooperate. As a result, excessive deformation of the isolator rubber is suppressed, and the durability of the pulley with isolation can be improved. When the coupling rubber starts to cooperate, the elastic deformation of the coupling rubber is gradually superimposed on the elastic deformation of the isolator rubber, so that it has a sufficient shock buffering force and a stronger driving force. Can communicate.

It is the perspective view seen from one side of the pulley with an isolation which is one embodiment. It is the perspective view seen from the opposite side surface of the pulley with an isolation shown by FIG. It is a perspective view which shows the longitudinal cross-sectional view of FIG. It is a perspective view which shows a coupling assembly. FIG. 5 is a front view for explaining a state of a coupling rubber assembly and a protrusion in an isolation pulley used for a vehicle having an ISG type idling stop mechanism or an ISG type hybrid vehicle. It is the sectional view on the AA line in FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, the isolation pulley P includes a hub 10 and a pulley body 20, and the hub 10 is integrated with the boss 11 and a boss 11 that is attached to a rotating shaft. And a radial portion 12 extending radially outward from the boss 11. The pulley body 20 includes a pulley portion 21 to which a belt (not shown) is attached, and a cover portion 22 that extends radially inward from one axial end portion of the pulley portion 21 and faces the radial portion 12. .

  As shown in FIG. 3, a rim portion 13 facing the pulley portion 21 is provided integrally with the radial portion 12 on the outer peripheral portion of the radial portion 12, and the rim portion 13 is axially directed toward the cover portion 22. It extends to. An annular mass body 15 is attached to the outside of the rim portion 13 via an annular damper rubber 14. The damper rubber 14 is formed of vulcanized rubber or the like, and is press-fitted between the outer peripheral surface of the rim portion 13 and the inner peripheral surface of the annular mass body 15 and is arranged coaxially with the rim portion 13. A resin-made journal bearing 16 is disposed between the annular mass body 15 and the pulley portion 21. The damper rubber 14 and the annular mass body 15 constitute a damper that reduces torsional vibration due to resonance of the eigenvalue of the engine.

  A cylindrical portion 17 is provided in the radial direction portion 12 so as to be located radially inward of the rim portion 13 so as to be integrated with the radial direction portion 12. The cylindrical portion 17 is coaxial with the rim portion 13 and has a rim. It faces the part 13. An isolator ring 23 is abutted against the radial portion 12 of the hub 10. The isolator ring 23 includes a radial abutting portion 24 that abuts against the radial portion 12 and an axial fitting portion 25 that is fitted to the outside of the cylindrical portion 17. The isolator ring 23 has an annular shape as a whole, and the abutting portion 24 and the fitting portion 25 are integrally formed by pressing using sheet metal. An isolator rubber 26 is disposed between the radial direction portion 12 and the cover portion 22 via an abutment portion 24 of the isolator ring 23. One end portion in the axial direction of the isolator rubber 26 is vulcanized and bonded to the cover portion 22, and the other end portion in the axial direction is vulcanized and bonded to the abutting portion 24 of the isolator ring 23.

  Thus, the isolator rubber 26 disposed between the cover portion 22 and the radial direction portion 12 is shear-deformed by the speed difference between the hub 10 and the pulley body 20 due to the torque fluctuation of the drive shaft, and driven. The torque fluctuation of the rotating shaft on the side is blocked from being transmitted to the driven rotating shaft. That is, the torque fluctuation of the driving side rotating shaft is insulated from the driven side rotating shaft. For example, when the pulley P with isolation is attached to the crankshaft of the engine and used to transmit to the main spindle of the accessories via a belt, it is caused by the torque fluctuation of the crankshaft when the engine is started or at low speed The crankshaft speed fluctuation is insulated by the isolator rubber 26.

  In order to apply an axial compressive force to the isolator rubber 26, a pressure ring 27 is abutted against the cover portion 22 as a pressing means. The pressure ring 27 includes a pressing portion 28 that is abutted against the outer surface of the cover portion 22 and a fitting portion 29 that is fitted to the fitting portion 25. The pressure ring 27 has an annular shape as a whole, and the pressing portion 28 and the fitting portion 29 are integrally formed by pressing using sheet metal. A resin-made thrust bearing 18 is disposed between the pressing portion 28 and the cover portion 22, and the pressure ring 27 is pressed against the cover portion 22 via the thrust bearing 18.

  The fitting part 25 of the isolator ring 23 is press-fitted outside the cylindrical part 17, and the fitting part 29 of the pressure ring 27 is coaxially fitted outside the fitting part 25. When the cylindrical portion 17, the fitting portion 25, and the fitting portion 29 are fitted to each other, the isolator rubber 26 is held in a precompressed state in the axial direction.

  In the pulley P with isolation shown in FIG. 3, the fitting portion 29 of the pressure ring 27 is fitted to the outside of the fitting portion 25 of the isolator ring 23, but the fitting portion 29 is fitted to the cylindrical portion 17. The isolator rubber 26 can be pre-compressed even when the fitting portion 25 is fitted outside the fitting portion 29.

  As shown in FIGS. 1 and 3, a coupling rubber assembly 31 is disposed between the other end portion of the pulley portion 21 and the radial direction portion 12. As shown in FIGS. 4 to 6, the coupling rubber assembly 31 includes a fixing ring 32 that is press-fitted and fixed to the inner peripheral surface of the pulley portion 21, and an engagement ring 33 that has a smaller diameter than the fixing ring 32. A coupling rubber 34 is vulcanized and bonded between the fixing ring 32 and the engagement ring 33. The coupling rubber 34 extends in the radial direction between the fixing ring 32 and the engagement ring 33, and the outer peripheral portion of the coupling rubber 34 is fixed to the other end portion of the pulley portion 21 via the fixing ring 32. An engagement ring 33 is attached to the inner periphery. In FIG. 6, symbol O is a central axis of the coupling rubber assembly 31, and the central axis O is coaxial with the central axis of the hub 10.

  A protrusion 35 that protrudes toward the coupling rubber assembly 31 is provided on the radial portion 12 of the hub 10. As shown in FIG. 1, three protrusions 35 are provided on the radial portion 12 with a constant interval in the circumferential direction. Each protrusion 35 protrudes into an arc-shaped long hole 36 provided in the engagement ring 33. As shown in FIG. 1, three elongated holes 36 are provided in the engagement ring 33 corresponding to the protrusions 35. The number of the protrusions 35 is not limited to three and can be any number.

  As shown in FIGS. 1 and 3, the surface of the radial portion 12 of the hub 10 that faces the coupling rubber assembly 31 is opposed to the coupling rubber assembly 31 and is longer than the long hole 36 of the engagement ring 33. A dust seal 38 is provided between the outer peripheral surface and the foreign matter from entering between the annular mass 15 and the pulley portion 21. In the present embodiment, the dust seal 38 is provided independently between the radial portion 12 and the engagement ring 33, but is integrated with the coupling rubber 34 as a lip-shaped dust seal portion extending toward the radial portion 12. It is good also as forming. The dust seal 38 may be provided between the coupling rubber assembly 31 and the annular mass body 15.

  FIG. 5 shows an isolation pulley used for a vehicle having an ISG type idling stop mechanism or an ISG type hybrid vehicle, and a protrusion 35 provided on the hub 10 is provided on the engagement ring of the coupling rubber assembly 31. An example assembled in a state of entering the long hole 36 is shown. The pulley with isolation shown in FIG. 5 is in a free state in which no load is applied in the twisting direction. As shown in FIG. 5, the protrusion 35 is relatively displaceable with respect to the engagement ring 33 within the range of the circumferential movement stroke of the long hole 36, and the relative movement of the protrusion 35 with respect to the long hole 36 is The protrusion 35 is regulated by contacting the end face of the long hole 36, and the driving force is transmitted to the coupling rubber 34. As described above, the protrusion 35 and the long hole 36 constitute an engagement mechanism that allows the engagement ring 33 and the hub 10 to be engaged and restricts the amount of elastic deformation of the isolator rubber 26. That is, when the amount of elastic deformation of the isolator rubber 26 exceeds a certain value, the coupling rubber 34 receives the rotational force of the drive side shaft and elastically deforms together with the isolator rubber 26. That is, the apparent spring constant of the composite elastic body composed of the isolator rubber 26 and the coupling rubber 34 that receives the driving force increases stepwise.

  As described above, the engagement mechanism includes the engagement state in which the projection 35 engages with the engagement ring 33 and the non-engagement in which the projection 35 and the engagement ring 33 do not engage with each other depending on the twist angle of the hub 10 with respect to the pulley body 20 It is possible to switch to the state. This prevents an excessive load from being applied to the isolator rubber 26, so that the isolator rubber 26 can be selected from a rubber having a hardness (spring constant) suitable for insulating torque fluctuations while maintaining durability. it can. Further, since the isolator rubber 26 and the coupling rubber 34 cooperate when the protrusion 35 and the engagement ring 33 are in the engaged state, the coupling rubber 34 also has a hardness having a sufficient shock buffering force ( A rubber having a spring constant) can be selected.

  For example, when the pulley P with isolation is mounted on the crankshaft of the engine and used to transmit the driving force of the engine to the main shafts of the auxiliary machinery via the belt, the crankshaft at the time of engine start-up or low rotation The transmission of the crankshaft speed fluctuation caused by the torque fluctuation to the driven rotary shaft is insulated by the isolator rubber 26. When the torque fluctuation of the crankshaft is large and the protrusion 35 engages with the engagement ring 33, the isolator rubber 26 and the coupling rubber 34 cooperate to receive a driving force.

  In addition, in a vehicle having an ISG type idling stop function, when the engine is started by a motor generator, a heavy crankshaft is driven via a belt. In the isolation pulley of the present invention, the isolator rubber 26 and The coupling rubber 34 cooperates to transmit driving force to the crankshaft. As described above, since soft (low spring constant) rubber can be used for the coupling rubber 34, the protrusion 35 of the engagement mechanism and the engagement ring 33 do not come into shock contact, It is difficult to generate a collision sound during engagement, and wear of the engaging portion can be suppressed. Further, since the impact contact can be prevented, the slip between the pulley and the belt can also be suppressed. Therefore, generation of unpleasant noise is suppressed, wear of the engaging portion and wear of the belt are suppressed, and durability of the pulley and the belt can be improved. Further, since the driving force at the time of starting the engine can be shared by the two rubbers, the load of each rubber, that is, the load of the driving force can be reduced, and in particular, the durability of the isolator rubber 26 can be improved.

  Also, in an ISG hybrid vehicle, the motor generator assists the engine. In some cases, when the motor generator is driven alone, the motor generator is continuously driven with a very strong driving force from an auxiliary weak driving force. However, in the pulley with isolation of the present invention, when a strong driving force is applied, the isolator rubber 26 and the coupling rubber 34 cooperate with each other. Since the strong driving force is shared by the two rubbers, the burden on each rubber can be reduced. Moreover, since soft (low spring constant) rubber | gum can be used for the coupling rubber 34, the shift | offset | difference of a non-engagement state and an engagement state can be performed smoothly. Therefore, it is difficult to generate a collision sound at the time of engagement, wear of the engaging portion can be suppressed, and impact contact can be prevented, so that slip between the pulley and the belt can also be suppressed. The durability of the pulley and belt can be improved.

  The operation status of the present embodiment will be described with reference to FIG. The coupling rubber assembly 31 is provided with one end face of the protrusion 35 and the long hole 36 when the pulley with isolation is in an unloaded state, that is, in a state where there is no speed difference between the hub 10 and the pulley body 20. If the stroke of relative movement between the projection 37 and the crankshaft drive side is S1, and the stroke of relative movement between the projection 35 and the other end surface 37e of the long hole 36e is S2, the space on the motor drive side is S2. The space S2 on the motor generator drive side is set shorter than the space S1 on the crankshaft drive side (S1> S2). The space S1 on the crankshaft drive side is a space on the forward rotation direction side of the crankshaft, and the space S2 on the motor generator drive side is a reverse direction, that is, a reverse rotation side space with respect to the space S1.

  Here, in the direction Te, the isolation pulley P incorporating the coupling rubber assembly 31 is mounted on the crankshaft, and the belt is stretched between the pulley of the motor generator (not shown) and the pulley body 20. The rotation direction of the crankshaft when the driving force of the engine is transmitted to the motor generator by the crankshaft is shown. The direction Tm indicates the rotational direction of the pulley body 20 (fixing ring 32) when the driving force of the motor generator is transmitted to the crankshaft.

  When the driving force is applied by the engine and the crankshaft rotates in the direction Te, the driving force is transmitted from the hub 10 side to the pulley body 20 (fixed ring 23) in the direction indicated by the direction Tea via the isolator rubber 26. At this time, during normal operation, the projection 35 provided on the hub sways (for example, 30 °) due to engine torque fluctuation (rotation unevenness), but the sway is within the spaces S1 and S2. 35 and the end faces 37e and 37m do not engage with each other. However, when the isolation rubber 26 is broken due to excessive excessive vibration at the time of starting the engine, the hub 10 and the protrusion 35 rotate counterclockwise to engage with the end surface 37e, and this engagement causes the pulley body 20 to rotate. Is rotated in the direction Tea. As a result, the driving force of the engine is transmitted to the pulley body 20, so that a rotational force is applied to the main shaft of the generator via the belt and power generation is continued. Since the engagement between the protrusion 35 and the end surface 37e is received by the soft coupling rubber 34, the engagement is not shocking and no belt slip or the like occurs.

  When the driving force is applied by the motor generator and the pulley body 20 (fixed ring 32) rotates in the direction Tm via the belt, the engagement ring 33 rotates counterclockwise and is provided on the engagement ring 33. The end surface 37m of the long hole 36 and the projection 35 provided on the hub 10 are engaged, and the engagement state is switched from the non-engaged state to the engaged state where the projection 35 is engaged with the end surface 37e. In order to promptly transmit the driving force by the motor generator, the space S2 between the protrusion 35 and the end surface 37m is within a range that does not hinder the above-described low-order vibration at the time of starting the engine and the vibration of the protrusion 35 due to torque fluctuation during normal operation. It is preferable to make it as narrow as possible. On the other hand, the space S1 between the projection 35 and the end surface 37e is desirably not engaged with the projection 35 and the end surface 37e except in an emergency such as the destruction of the isolation rubber 26. Wide (S1> S2). In addition, in order to prevent destruction of the isolation rubber 26, it is more preferable that the space S1 is engaged before the isolation rubber 26 is destroyed.

  When the protrusion 35 is engaged with the end faces 37e and 37m of the long hole 36, the speed difference between the protrusion 35 and the engagement ring 33 is small. Therefore, when the projection 35 is engaged with the engagement ring 33, it is possible to prevent a large engagement sound, that is, a contact sound from being generated. Moreover, even if the projection 35 engages with the end faces 37e and 37m of the engagement ring 33, the generation of wear powder due to the engagement is reduced.

  The protrusion 35 constituting the engagement mechanism is provided in the radial portion 12 of the hub 10 and the long hole 36 is provided in the engagement ring 33, but the protrusion 35 faces the engagement ring 33 toward the radial portion 12. It is good also as a form which provides the long hole 36 which protrudes and the protrusion 35 enters in the radial direction part 12. FIG.

In the coupling rubber assembly 31 described above, the fixing ring 32 has a larger diameter than the engagement ring 33, and the fixing ring 32 is press-fitted into the inner peripheral surface of the pulley portion 21. On the other hand, in a form in which the fixing ring 32 has a smaller diameter than the engagement ring 33, the fixing ring 32 is fixed to the radial direction portion of the hub 10, and the engagement ring 33 is located inside the pulley portion 21 and the pulley portion 21. It arrange | positions via a clearance gap with respect to an internal peripheral surface. In the pulley P with isolation in this form, the inner peripheral portion of the coupling rubber 34 is fixed to the radial direction portion of the hub 10, the engagement ring 33 is attached to the outer peripheral portion, and the protrusion 35 is provided on the pulley portion 21. . As described above, the protrusion 35 and the long hole 36 constituting the engagement mechanism are provided on either the hub 10 or the pulley portion 21.
In the present invention, the isolation rubber and the coupling rubber are used. However, the material is not limited to rubber, and for example, a resin elastomer can be used.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

10 hub 11 boss 12 radial portion 13 rim portion 14 damper rubber 15 annular mass body 20 pulley body 21 pulley portion 22 cover portion 26 isolator rubber 31 coupling rubber assembly 32 fixing ring 33 engagement ring 34 coupling rubber 35 protrusion 36 length Hole 37e, 37m End face 38 Dust seal

Claims (6)

A hub provided with a mounting portion attached to the rotating shaft, and a radial portion integrally extending to the mounting portion and extending radially outward;
A pulley body including a pulley portion to which a belt is attached, and a cover portion extending radially inward from one axial end portion of the pulley portion and facing the radial portion;
An isolator rubber disposed between the radial portion and the cover portion;
An engagement ring is attached, and an annular coupling rubber disposed between the other axial end portion of the pulley portion and the radial portion,
An engagement mechanism provided on the hub or the pulley portion and the engagement ring, and capable of engaging the engagement ring and the hub or the pulley portion;
Have
The pulley with an isolation, wherein the engagement mechanism can be switched between a non-engaged state and an engaged state depending on a twist angle of the hub with respect to the pulley body.   2. The pulley with isolation according to claim 1, wherein the coupling rubber is configured such that an outer peripheral portion of the coupling rubber is fixed to the other end portion of the pulley portion, and the engagement ring is formed on an inner peripheral portion of the coupling rubber. Installed pulley with isolation.   2. The pulley with isolation according to claim 1, wherein the coupling rubber has an isolation in which an inner peripheral portion of the coupling rubber is fixed to a radial direction portion of the hub and the engagement ring is attached to an outer peripheral portion. Pulley.   4. The pulley with isolation according to claim 2, wherein the engagement mechanism is provided in an arc-shaped long hole provided in the engagement ring, and a radial portion of the hub or the other end of the pulley. A pulley with isolation, comprising a protrusion protruding into the elongated hole.   5. The pulley with isolation according to claim 4, wherein when the pulley with isolation is in a no-load state, the position of the protrusion in the long hole of the engagement ring is closer to the crankshaft than the space in the forward rotation direction of the crankshaft. Isolation pulley with shorter reverse rotation space.   The pulley with isolation according to any one of claims 1 to 5, further comprising an annular mass body attached to the hub via an annular damper rubber on a rim portion provided to face the pulley portion. Pulley with isolation.

Images