JP2007002916A - Pulley with damper and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small-sized pulley with a damper manufacturable at low cost with less assembling man-hours and having a radially smaller dimension. <P>SOLUTION: This pulley 1 with the damper comprises a damper assembly 2 and a pulley assembly 3 assembled thereto. The damper assembly 2 comprises a hub 10 having a boss part 12 fitted to the crankshaft of an engine and an outer cylindrical part 14 formed integrally with the boss part 12 through a radial part 13 and an annular mass body 17 fitted to the outer cylindrical part 14 through an annular elastic body 16. The pulley assembly 3 comprises a pulley body 20 having a cylindrical part 22 with a pulley groove 21 in its outer peripheral part and a cover part 23. A projection 26 engaged with an engagement hole 27 formed in a radial part 13 is formed at the other end part of the annular elastic body 25 fixed, at its one end, to the pulley body 20. The pulley assembly 3 is fixed to the damper assembly 2 by an engagement system. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique of a pulley with a damper that is mounted on a crankshaft of an engine and transmits torque of the crankshaft to various auxiliary machines via an endless belt.

The pulley for transmitting the crankshaft rotation of the engine to various auxiliary machines mainly cuts off the crankshaft speed fluctuation caused by engine torque fluctuation at low engine speed, such as idling rotation, There is a pulley with a damper having a function of reducing torsional vibration of a shaft. This pulley with a damper is also called an isolation damper pulley. As described in Patent Document 1, a damper assembly to be mounted on a crankshaft and a pulley assembly in which an endless belt is stretched over the damper assembly. It has a solid.
International Publication No. 2005/005865 Pamphlet (Figure 1)

  The conventional damper assembly includes a hub attached to the crankshaft and an annular mass body fixed to the outer periphery of the hub via a first elastic body, and has a function of reducing torsional vibration of the crankshaft. Have. On the other hand, the pulley assembly includes a cover body having a cylindrical portion in which a pulley groove is formed on the outer peripheral portion and a cover portion extending in the center direction from one axial end portion of the cylindrical portion. One end of the elastic body is fixed, and an isolation ring is fixed to the other end of the elastic body. The isolation ring has a radial portion to which the other end portion of the second elastic body is fixed, and a fitting portion that fits into a cylindrical portion provided in the hub when the pulley assembly is assembled to the damper assembly. The second elastic body is fixed between the damper assembly and the pulley body via the isolation ring, and functions to block the crankshaft speed fluctuation caused by the crankshaft torque fluctuation at the time of low engine rotation. have.

  In the damper-equipped pulley in which the second elastic body is fitted to the cylindrical portion of the damper assembly at the fitting portion of the isolation ring fixed to the second elastic body, the second elastic body is attached to the cover body. When molding by vulcanization molding, since it is necessary to vulcanize and bond the isolation ring to the cover body via the second elastic body, a part of the mold that forms the inner peripheral surface of the second elastic body Must be disposed outside the fitting portion of the isolation ring, and a gap corresponding to the space for the mold is formed between the second elastic body and the fitting portion. As a result, the radial dimension of the pulley with a damper is increased.

  In the conventional pulley with a damper, in order to fix the isolation ring to the cover body via the second elastic body, in order to improve the adhesion between the isolation ring and the second elastic body at the time of vulcanization molding, After the surface of the isolation ring is roughened, an adhesive is applied, and when performing the roughening treatment and the adhesive application, it is necessary to mask the surface on which these treatments are not performed. In particular, the masking of the fitting portion of the isolation ring is an essential process in order to prevent the surface flatness from being impaired by the roughening treatment or the like.

  Further, a press-fitting step for pre-compressing the second elastic body by fitting the pressure ring to the fitting portion of the isolation ring on the cover body formed by vulcanizing the second elastic body, and covering the pressure ring After the fitting to the main body, a press-fitting process for fitting the cover main body to the damper assembly together with the pressure ring is necessary, and thus two press-fitting processes are necessary.

  An object of the present invention is to provide a small pulley with a damper having a small radial dimension by reducing a gap between an elastic body and a pressure ring.

  Another object of the present invention is to provide a pulley with a damper that can reduce an assembling man-hour without requiring an isolation ring for attaching an elastic body to the damper assembly.

  A pulley with a damper according to the present invention is a pulley with a damper that is attached to a crankshaft of an engine, and a boss portion provided with an attachment hole for the crankshaft, and a radial direction extending radially outward from the boss portion A damper assembly including a hub having a portion and an outer cylindrical portion provided in the radial direction portion, an annular mass body mounted on the outer cylindrical portion via a first elastic body, and a pulley on the outer peripheral portion A pulley body including a cylindrical portion formed in a groove and disposed outside the annular mass body, and a cover portion extending in a central direction from one axial end portion of the cylindrical portion, and one end fixed to the pulley main body, A meshing end portion that engages with an engagement portion formed in the radial direction portion is provided at the other end, a second elastic body that forms a pulley assembly with the pulley body, and a damper assembly that is provided in the damper assembly. Inside The second elastic body has a fitting portion to be fitted to the cylindrical portion, and presses the pulley main body in the axial direction in a state where the meshing end portion is engaged with the engaging portion. And a pressing member for applying axial pre-compression.

  In the present invention, the engaging portion and the meshing end portion that engages with the engaging portion have all the configurations in which both are integrally assembled and rotated when the engaging portion is engaged with the meshing end portion. It shall be said.

  The pulley with a damper according to the present invention is characterized in that the meshing end portion is formed by a plurality of protrusions, and the engagement portion is formed by an engagement hole with which the protrusion is engaged.

  The pulley with a damper according to the present invention is characterized in that a reinforcing ring is provided at the other end of the second elastic body, and a convex portion that engages with the engaging hole is provided on the reinforcing ring.

  The pulley with a damper according to the present invention is characterized in that the outer side of the convex portion is covered with a coating layer made of an elastic material connected to the second elastic body, and the coating layer contacts the engagement hole.

  A method for manufacturing a pulley with a damper according to the present invention is a method for manufacturing a pulley with a damper to be mounted on a crankshaft of an engine, and a boss portion provided with an attachment hole to the crankshaft, and a radial direction from the boss portion A damper assembly comprising a hub having a radially extending portion extending outward and an outer cylindrical portion provided in the radially extending portion, and an annular mass body mounted on the outer cylindrical portion via a first elastic body And a pulley main body including a cylindrical portion in which a pulley groove is formed in the outer peripheral portion and disposed outside the annular mass body, and a cover portion extending in the central direction from one axial end portion of the cylindrical portion. And a step of preparing a pulley assembly including a second elastic body having one end fixed to the pulley main body and a meshing end that engages with an engagement portion formed in the radial direction portion. And the chewing Under the state where the mating end is engaged with the engaging portion, the pressing portion facing the cover portion and the fitting portion fitted to the inner cylindrical portion provided in the damper assembly are provided. A pressing member is press-fitted into the inner fitting portion to apply axial precompression to the second elastic body by the radial portion and the pressing member, and an end surface of the damper assembly, the pulley groove, And a step of fitting the pressing member to the inner fitting portion at a position where the axial separation length becomes a predetermined value.

  According to the present invention, the engaging end is provided at the end of the second elastic body fixed to the pulley body of the pulley assembly, and the engaging end engages with the radial portion of the hub of the damper assembly. By providing the joint portion, the pulley assembly and the damper assembly are fixed by the engagement method, so that it is not necessary to attach an isolation ring to the pulley assembly. This eliminates the need for a mold placement gap between the outer peripheral surface of the fitting portion of the isolation ring and the inner peripheral surface of the second elastic body, and makes the second elastic body closer to the axis than before. Since the outer diameter of the pulley with a damper can be reduced, the pulley with a damper can be reduced in size.

  Since the isolation ring is not required, the surface of the isolation ring is roughened to improve the adhesion to the second elastic body, and masking of other parts during application of the adhesive is not required. The attached pulley can be manufactured with few steps. Further, the damper assembly side end portion of the second elastic body and the damper assembly are integrally assembled by the engagement method, and the second elastic body is pre-compressed by the pressing member. The press-fitting process using a machine can be reduced as compared with the case of using an isolation ring, and a pulley with a damper can be manufactured with fewer processes. Thereby, the pulley with a damper can be manufactured at low cost.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a damper-equipped pulley according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a state where the damper-equipped pulley shown in FIG. 1 is separated into a damper assembly and a pulley assembly. 3 is a cross-sectional view showing the assembly process of the pulley with a damper, and FIG. 4 is a front view of the pulley with a bumper as seen from the direction of arrow A in FIG.

  A pulley 1 with a damper according to the present invention includes a damper assembly 2 mounted on a crankshaft, and a pulley assembly 3 that is assembled to the damper assembly 2 and over which an endless belt is stretched. The damper assembly 2 has a hub 10, and the hub 10 has a cylindrical boss portion 12 formed with a mounting hole 11 through which a crankshaft (not shown) passes, and radially outward from the boss portion 12. A radial portion 13 that extends, and an outer cylindrical portion 14 that extends in the axial direction from the radial tip of the radial portion 13 and is coaxial with the central axis O of the boss portion 12 are provided. An inner cylindrical portion 15 having a smaller diameter than the outer cylindrical portion 14 and coaxial with the central axis O is provided in the radial direction portion 13 so as to be parallel to the outer cylindrical portion 14 and extend in the axial direction. Are formed integrally by casting, sheet metal rolling or the like.

  On the outer side of the outer cylindrical portion 14 of the hub 10, a damper rubber, that is, an annular elastic body 16 formed in an annular shape by an elastic material such as vulcanized rubber is disposed as a first elastic body. An inertia ring made of metal such as cast iron or cast steel, that is, an annular mass body 17 is disposed, and the annular elastic body 16 is press-fitted between the inner peripheral surface of the annular mass body 17 and the outer peripheral surface of the outer cylindrical portion 14. . The damper assembly 2 having such a structure is attached to the crankshaft via a key attached to a key groove 11a provided in the boss portion 12, and has a function of reducing torsional vibration of the crankshaft.

  On the other hand, the pulley assembly 3 has a pulley body 20, and the pulley body 20 has a cylindrical portion 22 in which a pulley groove 21 is formed on the outer peripheral portion, and radially inward from one axial end portion of the cylindrical portion 22. When the pulley assembly 3 is assembled to the damper assembly 2, the cylindrical portion 22 is disposed outside the annular mass body 17. A journal bearing 24 is provided between the inner peripheral surface of the cylindrical portion 22 and the outer peripheral surface of the annular mass body 17, and the journal bearing 24 is formed into a cylindrical shape with resin.

  An isolator rubber, that is, an annular elastic body 25 formed in an annular shape by an elastic material such as vulcanized rubber is fixed to the pulley main body 20 at one end thereof, and an annular elastic body as a second elastic body. A plurality of protrusions 26 are formed on the other end of the body 25, and the other end of the annular elastic body 25 is a meshing end provided with the protrusions 26. On the other hand, a plurality of engaging holes 27 are formed as engaging portions in the radial direction portion 13 of the hub 10 constituting the damper assembly 2 corresponding to each protrusion 26. As shown in FIG. 4, four engagement holes 27 are formed in the radial direction portion 13 at equal intervals in the circumferential direction, and the other end portions of the annular elastic body 25 are formed in the respective engagement holes 27. Correspondingly, four protrusions 26 are provided.

  A metal reinforcing ring 28 is provided at the other end of the annular elastic body 25, and the reinforcing ring 28 is inclined so that the radially inner portion is closer to the cover portion 23 than the radially outer portion. . The reinforcing ring 28 is integrally provided with a hollow convex portion 29 that protrudes in the axial direction on the opposite side to the cover portion 23, and the convex portion 29 is plastically processed when the reinforcing ring 28 is pressed. The ring 28 is embedded in the end of the annular elastic body 25 when the annular elastic body 25 is vulcanized and bonded to the pulley body 20. Thus, the pulley assembly 3 includes the pulley main body 20 and the annular elastic body 25 in which the reinforcing ring 28 is embedded. The convex portion 29 is formed by attaching a solid pin to the reinforcing ring 28 without forming the convex portion 29 integrally with the reinforcing ring 28 by pressing the reinforcing ring 28. You may make it do.

  The reinforcing ring 28 is covered with the rubber material of the annular elastic body 25 except for the inner peripheral surface 28a. The rubber material is embedded in the convex portion 29 and the outer surface of the convex portion 29 is made of a rubber material continuous with the annular elastic body 25. Covered by the covering layer 30. Thus, since the protrusion 26 is formed by the convex portion 29 of the reinforcing ring 28 embedded in the other end portion of the annular elastic body 25 and the covering layer 30 covered outside thereof, the protrusion engaging with the engaging hole 27. 26 is secured, and the rubber coating layer 30 comes into contact with the inner peripheral surface of the engagement hole 27, thereby preventing the generation of vibration noise.

  Further, since the surface of the reinforcing ring 28 on the damper assembly 2 side is also covered with the covering layer 30, the covering layer 30 is interposed between the reinforcing ring 28 and the hub 10, and the reinforcing ring 28 and the hub 10 are connected. There is no contact and the generation of vibration noise is prevented.

  In order to apply a compressive force to the annular elastic body 25 in a state where the pulley assembly 3 is assembled to the damper assembly 2 with the projections 26 engaged with the engagement holes 27, the inner cylindrical portion 15 of the hub 10 A metal pressure ring 31 is disposed on the outside as a pressing member. The pressure ring 31 is coaxial with the center axis O and is fitted into the inner cylindrical portion 15 and is fitted into the inner cylindrical portion 15, and a pressure radially extending from the end of the fitting portion 32. Part 33, and has a ring shape as a whole. The pressure ring 31 is formed by pressing using a plate material. A resin-made thrust bearing 34 is disposed between the pressing portion 33 and the cover portion 23, and the pressing portion 33 presses the cover portion 23 of the pulley assembly 3 via the thrust bearing 34. 25 is pre-compressed.

  Thus, when the damper assembly 2 and the pulley assembly 3 are assembled, a predetermined precompression can be applied to the annular elastic body 25 in the axial direction, and the fitting portion 32 of the pressure ring 31 and the hub 10 can be applied. The relative position in the axial direction between the damper assembly 2 and the pulley assembly 3 can be adjusted by adjusting the position in the axial direction with respect to the inner cylindrical portion 15. The distance L in the axial direction from the pulley groove 21 at the center in the direction can be adjusted. Therefore, the axial position of the pulley assembly 3 with respect to the damper assembly 2, that is, the separation length L can be kept within a predetermined tolerance range while maintaining the precompression applied to the annular elastic body 25 within an allowable range. Therefore, it becomes unnecessary to process the pulley body 20 and the pressure ring 31 with high accuracy.

  Next, the manufacturing method of the pulley 1 with a damper which is this Embodiment is demonstrated based on FIG. 2 and FIG.

  The damper assembly 2 is formed by subjecting a hub 10 formed by casting using a metal material such as cast iron or cast steel to a predetermined machining process such as polishing, and then forming an annular mass outside the hub 10 via an annular elastic body 16. By assembling the body 17, as shown in FIG.

  On the other hand, a pulley body 20 molded by casting using a metal material such as cast iron or cast steel, together with a press-worked reinforcing ring 28, is placed in a mold for vulcanization molding and flows into the mold. Inject rubber material. Thus, the annular elastic body 25 is molded, and the reinforcing ring 28 is covered with vulcanized rubber and embedded in the end portion of the annular elastic body 25, and the annular elastic body 25 is fixed to the cover portion 23 at the end portion. The In this way, the pulley assembly 3 is manufactured in advance in the preparation process. In this way, after the pulley assembly 3 is manufactured by vulcanizing and bonding the annular elastic body 25 to the pulley body 20 by the molding die, the journal bearing 24 is provided inside the cylindrical portion 22 as shown in FIG. It is assembled to solid 3. In addition, you may make it provide a coating layer with a vulcanized rubber in the inner peripheral part of the opposite side surface of the cover part 23 at the time of shaping | molding.

  In order to assemble the pulley assembly 3 to the damper assembly 2, the pulley assembly 3 is disposed on the damper assembly 2 in a state where the damper assembly 2 is disposed on a mold (not shown), as shown in FIG. Thus, the protrusion 26 of the annular elastic body 25 of the pulley assembly 3 is engaged with the engagement hole 27 of the damper assembly 2. At this time, by aligning the positions of the protrusions 26 and the engagement holes 27 and disposing the pulley assembly 3 in the mold, the damper assembly 2 and the pulley assembly 3 can be easily connected without using a hydraulic actuator. Can be assembled.

  Next, with the thrust bearing 34 interposed between the cover portion 23 of the pulley assembly 3 and the pressing portion 33 of the pressure ring 31, the fitting portion 32 of the pressure ring 31 is connected to the inner cylinder of the hub 10. The fitting portion 32 and the inner cylindrical portion 15 are fitted by press-fitting the portion 15 in the axial direction using a hydraulic actuator (not shown). As a result, the damper assembly 2 and the pulley assembly 3 are assembled in a state where a predetermined precompression is applied to the annular elastic body 25 in the axial direction. In the pulley 1 with a damper assembled in this way, the radius of the inner cylindrical portion 15 is R0, the radius of the inner peripheral surface of the annular elastic body 25 is Ra, and the radius of the pulley assembly 3 is Rb.

  FIG. 5 is a cross-sectional view showing a conventional pulley 1A with a damper shown as a comparative example. In FIG. 5, members having the same functions as those of the component 1 of the pulley 1 with a damper of the present invention are denoted by the same reference numerals. ing.

  As shown in FIG. 5, a conventional pulley 1 </ b> A with a damper is provided with an isolation ring 41 that is fixed to the cover portion 23 of the pulley assembly 3 via an annular elastic body 25. The isolation ring 41 includes a support portion 42 fixed to the annular elastic body 25 and a fitting portion 43 that is integrated with the support portion 42 and is fitted to the fitting portion 32 of the pressure ring 31. As described above, the conventional pulley 1A with a damper is configured such that the isolation ring 41 is fitted to the inner cylindrical portion 15 of the hub 10 via the fitting portion 32 of the pressure ring 31, thereby the annular elastic body 25 by a fitting method. Is fixed to the hub 10, so that the pre-compression is applied to the annular elastic body 25, the fitting portion 32 of the pressure ring 31 and the fitting portion 43 of the isolation ring 41 are connected using a press machine. In addition to the press-fitting process for press-fitting, the pulley assembly 3 to which the pressure ring 31 is assembled is press-fitted into the inner cylindrical portion 15 of the hub 10 by using a press machine to press-fit the pulley assembly 3 to the hub 10 and the pulley assembly. A press-fitting process for assembling the solid 3 is required.

  On the other hand, in the pulley 1 with a damper according to the present invention, the protrusion 26 provided at the end of the annular elastic body 25 has an engagement hole formed in the radial direction portion 13 of the hub 10 of the damper assembly 2. 27, the pressure ring 31 as a pressing member is fitted into the inner cylindrical portion 15 to apply pre-compression to the annular elastic body 25, and the end face of the damper assembly 2 and the pulley assembly. Since the axial separation length L with respect to the three pulley grooves 21 is set, the pulley 1 with a damper can be assembled in one press-fitting process.

  Further, in the conventional pulley 1A with a damper, the annular elastic body 25 is fixed to the hub 10 by a fitting method. In order to improve the adhesion between the surface of the support portion 42 of the isolation ring 41 and the annular elastic body 25, it is necessary to apply an adhesive after the surface of the support portion 42 is roughened. Since the fitting portion 32 is fitted to the inner cylindrical portion 15, it is necessary to finish the surface flat. When performing the roughening process and the adhesive application of the support portion 42, the fitting portion 32 is covered and masked. There is a need to.

  For this reason, in order to manufacture the pulley 1A with a damper conventionally, not only many press-fitting processes but a masking process is needed, Therefore The manufacturing cost of the pulley 1A with a damper becomes high. On the other hand, the damper-equipped pulley 1 according to the present invention has the annular elastic body 25 by the engagement method in which the annular elastic body 25 is directly engaged with the radial portion 13 of the hub 10 at the meshing end of the end portion. Since it is attached to the hub 10 and the isolation ring 41 is not used, the masking process of the isolation ring 41 is not necessary. A reinforcing ring 28 is embedded in the end portion of the annular elastic body 25. Since the reinforcing ring 28 does not have a fitting portion, the entire reinforcing ring 28 is roughened without using masking. And adhesive application.

  Further, in the fitting method as in the conventional pulley 1A with a damper, when the annular elastic body 25 is formed using a mold, the pulley body 20 and the isolation ring 41 are added via the annular elastic body 25. In order to perform adhesive bonding, it is necessary to dispose a portion of the mold that molds the inner peripheral surface of the annular elastic body 25 outside the fitting portion 43 of the isolation ring 41. Therefore, in order to maintain a desired mold strength, a space 44 having a desired thickness is provided between the inner peripheral surface of the annular elastic body 25 and the fitting portion 43, as shown in FIG. A part of the mold needs to enter the space 44. For this reason, when the outer diameter of the inner cylindrical portion 15 of the hub 10 is the same radius R0 as the radius R0 of the damper-equipped pulley 1 shown in FIG. 1, the inner diameter of the annular elastic body 25 is set to the pulley with the damper of the present invention. If the inner diameter Ra of the pulley 1A with the damper is not set larger than the outer diameter Rb of the pulley 1 with the damper, the same torsional vibration is caused. A reduction function and a speed fluctuation blocking function could not be obtained. For this reason, there is a limit to downsizing the pulley with damper 1A. However, according to the present invention, the damper assembly 2 and the pulley assembly 3 are fixed by the engagement method. The outer diameter Rb of the pulley can be made smaller than before, and the pulley 1 with a damper can be miniaturized.

  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. For example, the radial portion 13 of the hub 10 has a disc shape or a disc shape, but the radial portion 13 may be formed by a plurality of rod-like members each having a notch. Further, the protrusions 26 are provided at the end portions of the annular elastic body 25 so that the end portions of the annular elastic body 25 are engaged with each other, but the engagement holes are provided by providing engagement holes at the end portions of the annular elastic body 25. A projection that engages with the engagement hole may be formed on the radial direction portion 13 of the hub 10.

It is sectional drawing which shows the pulley with a damper which is one embodiment of this invention. It is sectional drawing which shows the state which isolate | separated the pulley with a damper shown by FIG. 1 into the damper assembly and the pulley assembly. It is sectional drawing which shows the assembly process of a pulley with a damper. It is a front view of the pulley with a bumper seen from the arrow A direction in FIG. It is sectional drawing which shows the conventional pulley with a damper shown as a comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pulley with damper 2 Damper assembly 3 Pulley assembly 10 Hub 11 Mounting hole 12 Boss part 13 Radial direction part 14 Outer cylindrical part 15 Inner cylindrical part 16 Annular elastic body (first annular elastic body)
17 annular mass body 20 pulley body 21 pulley groove 22 cylindrical portion 23 cover portion 25 annular elastic body (second annular elastic body)
26 Protrusion 27 Engagement hole 28 Reinforcement ring 30 Cover layer 31 Pressure ring (pressing member)
32 fitting part 33 pressing part

Claims (5)

A pulley with a damper attached to the crankshaft of the engine,
A hub having a boss part provided with a mounting hole for the crankshaft, a radial part extending radially outward from the boss part, and an outer cylindrical part provided in the radial part, and the outer cylinder A damper assembly comprising an annular mass mounted on the part via a first elastic body;
A pulley main body including a cylindrical portion in which a pulley groove is formed on the outer peripheral portion and disposed outside the annular mass body, and a cover portion extending in the center direction from one axial end portion of the cylindrical portion;
A second elastic body, one end of which is fixed to the pulley body and the other end of which is provided with a meshing end portion that engages with an engaging portion formed in the radial direction portion and forms a pulley assembly with the pulley body. When,
The pulley main body in the axial direction has a fitting portion that is fitted to an inner cylindrical portion provided in the damper assembly, and the engagement end portion is engaged with the engagement portion. A pulley with a damper, comprising: a pressing member that presses and applies axial pre-compression to the second elastic body.   The pulley with a damper according to claim 1, wherein the engagement end portion is formed by a plurality of protrusions, and the engagement portion is formed by an engagement hole with which the protrusion is engaged.   The pulley with a damper according to claim 2, wherein a reinforcing ring is provided at the other end of the second elastic body, and a protrusion that engages with the engaging hole is provided on the reinforcing ring.   The pulley with a damper according to claim 3, wherein an outer side of the convex portion is covered with a coating layer made of an elastic material connected to the second elastic body, and the coating layer is in contact with the engagement hole. Pulley with. A method of manufacturing a pulley with a damper to be mounted on a crankshaft of an engine,
A hub having a boss part provided with a mounting hole for the crankshaft, a radial part extending radially outward from the boss part, and an outer cylindrical part provided in the radial part, and the outer cylinder Preparing a damper assembly comprising an annular mass mounted on the part via a first elastic body;
A pulley main body comprising a cylindrical portion formed on the outer periphery of which a pulley groove is formed and disposed outside the annular mass body, a cover portion extending in the center direction from one axial end of the cylindrical portion, and one end of the pulley main body Preparing a pulley assembly comprising a second elastic body fixed at the other end and having a meshing end portion engaged with an engagement portion formed in the radial direction portion at the other end;
With the engagement end portion engaged with the engagement portion, a pressing portion facing the cover portion and a fitting portion fitted to an inner cylindrical portion provided in the damper assembly The pressing member having the inner fitting portion is press-fitted to apply axial pre-compression to the second elastic body by the radial portion and the pressing member, and the end face of the damper assembly and the pulley groove And a step of fitting the pressing member into the inner fitting portion at a position where the axial separation length becomes a predetermined value.

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