JP2007162840A - Pulley and engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pulley and an engine securing sound insulation, and capable of improving maintainability by reducing the number of components. <P>SOLUTION: This pulley is provided with a pulley body 13 fixed to a rotary shaft 5 by using a fixing bolt 25, a sound insulation part 17 attached to the pulley body 13 so as to cover the fixing bolt 25, and an attaching part 15 holding the sound insulation part 17 with the pulley body 13, the sound insulation part 17 is provided with an elastic member comprised of an elastic material in a portion tangent to at least the pulley body 13 and the attachment part 15, a holding part 37 forming a gap for holding the sound insulation part 17 is provided on at least one of the pulley body 13 or the attachment part 15, and regulating faces 29A, 29B regulating an interval of the gap in the holding part 37 at a predetermined interval by contacting each other, are provided on the pulley body 13 and the attachment part 15. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention
The present invention relates to a pulley used as an engine crank pulley and an engine including the pulley.

In recent years, it has been required to reduce noise generated during driving in passenger cars, industrial vehicles, and the like. Most of the noise generated during operation of these vehicles and the like is generated from the internal combustion engine on which the vehicle is mounted, and it is required to reduce the noise generated from the internal combustion engine.
Noise is generated from various parts of the internal combustion engine, and particularly noise generated from a fixing bolt for fixing the crank pulley to the crankshaft is large. Since the noise generated from the internal combustion engine can be effectively reduced by insulating the noise generated from the fixing bolts, a method of mounting the sound insulating cover on the end face of the crank pulley to provide sound insulation has been proposed ( For example, see Patent Documents 1 and 2.)
Japanese Patent Laid-Open No. 10-252866 (page 3, FIG. 1, etc.) JP-A-10-252867 (2nd page, FIG. 8 etc.)

In the above-mentioned Patent Document 1, a configuration of a crank pulley including a crank pulley main body, a fixing bolt for fixing the main body to the crankshaft, a sound insulating cover, and a mounting bolt for fixing the sound insulating cover is disclosed.
According to this crank pulley, since the sound insulation cover is attached to the end face of the main body so as to cover the fixing bolt, it is described that noise generated from the fixing bolt can be sound-insulated.
However, the sound insulation cover is attached to the crank pulley by mounting bolts, and is fixed by mounting bolts at least at four or more locations in order to stably mount the sound insulation cover. Then, there was a problem that the number of parts of the crank pulley increased. Further, when removing the sound insulation cover during engine maintenance, it is necessary to remove and attach four or more mounting bolts, resulting in a deterioration in serviceability.

In Patent Document 2 described above, a crank pulley, a fixing bolt for fixing the crank pulley to the crankshaft, a soundproof cover made of a vibration-proof steel plate and a ring-shaped rubber sheet, and a mounting bolt for attaching the soundproof cover to the crank pulley And the structure of the clamp pulley provided with these is disclosed.
According to this crank pulley, since the sound insulation cover is attached to the end face of the main body so as to cover the fixing bolt, it is described that noise generated from the fixing bolt can be sound-insulated.
However, the sound insulation cover is attached to the crank pulley by mounting bolts, and is fixed by mounting bolts at least at four or more locations in order to stably mount the sound insulation cover. Then, there was a problem that the number of parts of the crank pulley increased. Further, when removing the sound insulation cover during engine maintenance, it is necessary to remove and attach four or more mounting bolts, which causes a problem of deterioration in maintainability.

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a pulley and an engine capable of ensuring sound insulation and improving maintainability by reducing the number of parts. To do.

In order to achieve the above object, the present invention provides the following means.
The pulley of the present invention includes a pulley main body fixed to a rotating shaft using a fixing bolt, a sound insulation portion attached to the pulley main body so as to cover the fixing bolt, and attached to the pulley main body. A mounting portion sandwiching the sound insulating portion therebetween, the sound insulating portion including an elastic member made of an elastic material at least in a portion contacting the pulley main body and the mounting portion, and at least one of the pulley main body and the mounting portion A holding surface that forms a gap in which the sound insulation portion is held, and the pulley body and the mounting portion are in contact with each other, thereby regulating a gap between the gaps in the holding portion to a predetermined interval. Is provided.

According to the present invention, since the sound insulation portion can be attached to the pulley body by attaching the attachment portion to the pulley body, the sound insulation can be secured and the number of parts can be reduced to improve the maintainability.
In order to sandwich the sound insulation portion between the attachment portion and the pulley body, the sound insulation portion is attached to the pulley body by sandwiching the circumferential end thereof. Therefore, the sound insulation part can be stably attached to the pulley body without using a plurality of mounting bolts, and the number of parts can be reduced.
In addition, since the sound insulation part is fixed to the pulley body with one mounting part, the number of steps required for attaching and detaching the sound insulation part can be reduced compared to the method of fixing the sound insulation part to the pulley body with a plurality of mounting bolts, and maintenance is performed. Can be improved.
Since the sound insulation part includes an elastic member at least in a portion in contact with the pulley body and the attachment part, it is possible to prevent the vibration of the pulley body and the attachment part from being transmitted to the sound insulation part. Therefore, the sound insulation can be further ensured as compared with the method of directly attaching the sound insulation part to the pulley body without using an elastic member.
At least one of the pulley main body and the mounting portion is provided with a holding portion that forms a gap for holding the sound insulating portion, and the pulley main body and the mounting portion are provided with a regulating surface that regulates the gap interval in the holding portion. Therefore, it is possible to more reliably prevent the vibration of the pulley main body and the attachment portion from being transmitted to the sound insulation portion. When the attachment portion is attached to the pulley main body, the interval between the holding portions is restricted by the contact between the restriction surfaces. An elastic member is provided in a portion of the sound insulating portion that comes into contact with the holding portion. Since the space | interval in a holding | maintenance part is controlled by a predetermined space | interval, it can prevent that an elastic member is compressed too much and it can prevent more reliably that the vibration of a pulley main body and an attaching part is transmitted to a sound insulation part.

  In the above invention, the mounting portion is provided with a female screw portion having a thread formed on the inner peripheral surface, and the pulley body is formed with a screw thread that is screwed with the female screw portion on the outer peripheral surface. It is desirable that a male screw portion is provided.

According to the present invention, since the female screw portion is provided in the attachment portion and the male screw portion is provided in the pulley main body, the sound insulating portion can be easily attached to and detached from the pulley main body.
By relatively rotating the female screw portion of the attachment portion and the male screw portion of the pulley body in one rotation direction, the attachment portion can be attached to the pulley body, and the sound insulation portion can be attached to the pulley body. On the other hand, by relatively rotating the female screw portion and the male screw portion in other rotational directions, the attachment portion can be removed from the pulley body, and the sound insulation portion can be removed from the pulley body. Therefore, compared with the method of fixing a sound insulation part to a pulley main body with a some mounting | wearing bolt, a sound insulation part can be easily attached or detached to a pulley main body.

In the above invention, a male screw portion is formed on the outer peripheral surface of the mounting portion,
It is desirable that the pulley main body is provided with a female screw portion having an inner peripheral surface formed with a screw thread that is screwed with the male screw portion.

According to the present invention, since the male screw portion is provided in the attachment portion and the female screw portion is provided in the pulley main body, the sound insulating portion can be easily attached to and detached from the pulley main body.
By relatively rotating the male screw portion of the attachment portion and the female screw portion of the pulley body in one rotational direction, the attachment portion can be attached to the pulley body, and the sound insulation portion can be attached to the pulley body. On the other hand, by relatively rotating the female screw portion and the male screw portion in other rotational directions, the attachment portion can be removed from the pulley body, and the sound insulation portion can be removed from the pulley body. Therefore, compared with the method of fixing a sound insulation part to a pulley main body with a some mounting | wearing bolt, a sound insulation part can be easily attached or detached to a pulley main body.
Since the female thread portion is provided on the pulley body, the thread of the female thread portion is not exposed to the outer peripheral surface when the attachment portion is removed from the pulley body, and the pulley body is easily handled.

  In the said invention, it is desirable that the said sound insulation part is an elastic sheet formed from the elastic material.

According to the present invention, since the sound insulation portion is an elastic sheet formed of an elastic material, sound insulation can be secured. That is, since the elastic sheet formed from an elastic material is attached to the pulley body so as to cover the fixing bolt, noise generated from the fixing bolt can be insulated.
Since the sound insulating portion is an elastic sheet formed of an elastic material, the elastic member is in a state where it is in contact with the pulley body and the mounting portion. Therefore, it is easy to form the sound insulation part.

  In the said invention, it is desirable for the elastic sheet in the said sound insulation part to be equipped with the weight member.

  According to the present invention, since the weight member is provided in the elastic sheet, it is easier to ensure sound insulation. That is, by providing the elastic sheet with the weight member, the sound insulation characteristics of the sound insulation portion can be changed. By setting the mass of the weight member to a predetermined mass, the sound insulation property of the sound insulation portion can be adjusted to a property that can effectively sound the noise generated from the fixing bolt, and the sound insulation property can be further ensured.

  In the said invention, it is desirable for the said sound-insulation part to provide the board member formed from the metal material, and the elastic member provided in the edge of this board member.

According to the present invention, since the sound insulating part includes the plate member formed of a metal material and the elastic member provided at the edge of the plate member, the sound insulating property can be ensured. That is, since the sound insulation part is attached to the pulley body so as to cover the fixing bolt, noise generated from the fixing bolt can be insulated.
Since the elastic member is provided only at the edge of the plate member, the amount of the elastic member used in the sound insulating portion can be reduced.

  The pulley of the present invention is arranged between a pulley main body fixed to a rotating shaft using a fixing bolt, a sound insulating part attached to the pulley main body so as to cover the fixing bolt, and between the pulley main body and the sound insulating part. And a sound absorbing member.

  According to the present invention, it is easier to ensure sound insulation by arranging the sound absorbing member between the pulley body and the sound insulation part. That is, compared with the case where nothing is arranged between the pulley main body and the sound insulation part, the sound absorbing member absorbs noise, so that the noise generated from the fixing bolt echoes in the space between the pulley main body and the sound insulation member. This can be prevented and the sound insulation can be more easily secured.

  An engine according to the present invention includes a rotating shaft that transmits a rotational driving force, and a pulley that is fixed to the rotating shaft using a fixing bolt and transmits the rotational driving force of the rotating shaft to an auxiliary device via a belt. It is an engine, Comprising: The said pulley is a pulley in any one of Claims 1-7, It is characterized by the above-mentioned.

  According to the present invention, by using the pulley of the present invention, it is possible to ensure sound insulation of noise generated from the fixing bolt. Also, the maintenance of the engine can be improved by reducing the number of pulley parts.

  According to the pulley and the engine of the present invention, the sound insulation part can be attached to the pulley body by attaching the attachment part to the pulley body, so that the sound insulation is ensured and the number of parts is reduced to improve the maintainability. There is an effect that can be.

[First Embodiment]
Hereinafter, an engine according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3.
FIG. 1 is a schematic diagram illustrating the configuration of the engine according to the present embodiment.
As shown in FIG. 1, the engine 1 includes an engine body 3, a crank pulley (pulley) 7 fixed to a crankshaft (rotary shaft) 5, and a generator (auxiliary machine) 9 attached to the engine body 3. A belt 11 wound between the crank pulley 7 and the generator 9 is provided.
The engine 1 generates rotational driving force by burning supplied fuel and supplies the rotational driving force generated via the crankshaft 5 to the outside. Examples of the engine 1 include a diesel engine and a gasoline engine. Moreover, as a rotational speed of the engine 1, the range from about 800 rpm to 2800 rpm can be illustrated. The generator 9 is rotationally driven by the engine 1 and generates electricity. The generated electricity is supplied to an ignition plug or the like of the engine 1. The belt 11 transmits the rotational driving force transmitted to the crankshaft 5 to the generator 9 via the crank pulley 7. The belt 11 is wound around a crank pulley 7 and is also wound around a pulley attached to the generator 9.

FIG. 2 is a partial cross-sectional view illustrating the configuration of the crank pulley of FIG.
As shown in FIG. 2, the crank pulley 7 includes a pulley main body 13 fixed to the crankshaft 5, an attachment portion 15 attached to the pulley main body 13, and a prevention body disposed between the pulley main body 13 and the attachment portion 15. A vibration rubber sheet (sound insulating part, elastic member, elastic sheet) 17 is provided.

The pulley body 13 is formed in a bottomed cylindrical shape having a bottom surface 19 and a cylindrical portion 21, and transmits the rotational driving force transmitted from the crankshaft 5 to the belt 11.
A through hole 23 is formed at the center of the bottom surface 19 of the pulley body 13. A fixing bolt 25 is inserted into the through hole 23, and the pulley body 13 is fixed to the crankshaft 5 by screwing the fixing bolt 25 and the crankshaft 5.
In the cylindrical portion 21 of the pulley body 13, a belt groove 27 around which the belt 11 is wound, a regulation surface 29 </ b> A that contacts the regulation surface 29 </ b> B of the attachment portion 15, and a male screw that is screwed with the female screw portion 35 of the attachment portion 15. Part 31 is provided. The belt groove 27 is an annular groove formed in the vicinity of the end portion on the bottom surface 19 side in the cylindrical portion 21 and having a substantially trapezoidal cross section. The restricting surface 29 </ b> A is a flat surface formed between the belt groove 27 and the male screw portion 31, and is a substantially ring-shaped flat surface that is substantially perpendicular to the central axis C of the crankshaft 5. The male screw portion 31 is a substantially cylindrical protruding portion provided on the inner peripheral side of the opening side (left side in FIG. 2) of the pulley body 13. On the outer peripheral surface of the male screw portion 31, a screw thread that is screwed with the screw thread of the female screw portion 35 is formed. An anti-vibration rubber sheet 17 is disposed on the front end surface (left end surface) of the male screw portion 31.

The attachment portion 15 is attached to the pulley main body 13 and attaches the vibration-proof rubber sheet 17 to the pulley main body 13 by sandwiching the vibration-proof rubber sheet 17 between the pulley main body 13. Examples of the material for forming the attachment portion 15 include iron-based materials such as stainless steel.
The attachment portion 15 includes a ring plate portion 33 that sandwiches the vibration isolating rubber sheet 17 between the pulley main body 13 and a female screw portion 35 that is screwed into the male screw portion 31 of the pulley main body 13.

FIG. 3 is a front view for explaining the configuration of the attachment portion of FIG. 2.
The ring plate portion 33 is formed with a holding portion 37 on one surface (the right surface in FIG. 2) facing the pulley body 13, and the other surface (the left surface in FIG. 2) has a counterbored hole. 39 is formed.
The holding portion 37 is a ring-shaped concave surface formed on the inner peripheral side of one surface of the ring plate portion 33, and on the other surface side (the left side in FIG. 2) toward the radially inner peripheral side. It is a concave surface. The anti-vibration rubber sheet 17 is sandwiched and held between the front end surface of the male screw portion 31 and the holding portion 37. As shown in FIG. 3, the counterbore holes 39 are three holes formed on the other surface of the ring plate portion 33, and are arranged at equal intervals on the same circumference. The attaching portion 15 is rotated by using a jig (not shown) having a protruding portion inserted into the counterbore hole 39, and attached to and removed from the pulley body 13.
As described above, three counterbore holes 39 or four or more counterbore holes 39 may be provided in the attachment portion 15, and there is no particular limitation. However, the number of counterbore holes 39 is preferably three or more.
As described above, when attaching the attachment portion 15 to the pulley body 13, a jig may be attached to the counterbore hole 39 to rotate the attachment portion 15, or a jig (for example, The attachment portion 15 may be rotated by winding a jig having a belt wound around the outer peripheral surface, and is not particularly limited.

  As shown in FIG. 2, the female thread portion 35 is a substantially cylindrical protruding portion that extends from the outer peripheral side of one surface of the ring plate portion 33 to the pulley body 13 side (right side in FIG. 2). On the inner peripheral surface of the female screw portion 35, a screw thread to be screwed with the screw thread of the male screw portion 31 is formed. A restriction surface 29 </ b> B that contacts the restriction surface 29 </ b> A of the pulley body 13 is formed at the distal end portion (the right end portion in FIG. 2) of the female screw portion 35. The restricting surface 29B is a plane that is substantially perpendicular to the central axis C of the crankshaft 5. The contact between the restriction surface 29A and the restriction surface 29B keeps the distance between the front end surface of the male screw portion 31 and the holding portion 37 at a predetermined distance.

As shown in FIG. 2, the anti-vibration rubber sheet 17 is a rubber sheet formed in a disk shape and insulates noise generated from the fixing bolt 25.
Examples of the rubber forming the vibration-insulating rubber sheet 17 include silicon rubber and butyl rubber. Other known rubbers may be used and are not particularly limited.
The anti-vibration rubber sheet 17 is formed so that the thickness is at least thicker than the distance between the front end surface of the male screw portion 31 and the holding portion 37 in the circumferential portion that contacts the pulley body 13 and the attachment portion 15. ing. By doing so, the anti-vibration rubber sheet 17 can be reliably held between the male screw portion 31 and the holding portion 37. Further, the thickness of the circumferential portion of the anti-vibration rubber sheet 17 is formed so as not to be thicker than a predetermined value with respect to the interval. By doing in this way, it can prevent that the vibration proof rubber sheet 17 is compressed too much in the said circumference part. By preventing over-compression, it is possible to prevent the vibration of the pulley main body 13 and the attachment portion 15 from being transmitted to the central portion of the vibration-proof rubber sheet 17.

Next, functions of the engine 1 and the crank pulley 7 in this embodiment will be described.
First, transmission of rotational driving force in the engine 1 and the crank pulley will be described.
As shown in FIG. 1, the engine 1 generates a rotational driving force by burning the supplied fuel, and supplies the rotational driving force generated via the crankshaft 5 to the outside. A part of the rotational driving force transmitted to the crankshaft 5 is transmitted from the crankshaft 5 to the pulley body 13 as shown in FIG. The rotational driving force transmitted to the pulley body 13 is transmitted to the belt 11 wound around the belt groove 27. The rotational driving force transmitted to the belt 11 is transmitted to the generator 9 and the like via the belt 11 as shown in FIG. The generator 9 is rotationally driven by the transmitted rotational driving force to generate power. Part of the electric power generated by the generator 9 is supplied to an ignition plug of the engine 1 or the like.

Next, sound insulation in the crank pulley 7 which is a feature of the present embodiment will be described.
Noise generated from the fixing bolt 25 is transmitted into the pulley body 13 of the crank pulley 7. Noise transmitted to the inside of the pulley body 13 is blocked by the anti-vibration rubber sheet 17 disposed at the opening of the pulley body 13 and is prevented from being transmitted from the crank pulley 7 to the outside.
On the other hand, the vibration transmitted from the fixing bolt 25 or the crankshaft 5 to the pulley body 13 is also transmitted to the attachment portion 15. The vibration transmitted to the pulley main body 13 and the attachment portion 15 is transmitted from the tip of the male screw portion 31 and the holding portion 37 to the circumferential portion of the anti-vibration rubber sheet 17. When vibration is transmitted to the circumferential portion of the anti-vibration rubber sheet 17, the vibration is attenuated by the elasticity of the anti-vibration rubber sheet 17 and the vibration is prevented from being transmitted to the central portion of the anti-vibration rubber sheet 17.

Next, attachment / detachment of the attachment portion 15 and the vibration-proof rubber sheet 17 in the crank pulley 7 will be described.
When the attachment portion 15 and the vibration isolating rubber sheet 17 are attached to the pulley main body 13, as shown in FIG. 2, the vibration isolating rubber sheet 17 is disposed between the pulley main body 13 and the attachment portion 15, and the pulley main body 13. The mounting portion 15 is screwed onto the screw.
Specifically, the anti-vibration rubber sheet 17 is disposed so as to be sandwiched between the front end surface of the male screw portion 31 in the pulley body 13 and the holding portion 37 in the attachment portion 15. Then, the male thread part 31 of the pulley body 13 and the female thread part 35 of the attachment part 15 are screwed together. The attachment portion 15 is attached to the pulley body 13 so that the regulation surfaces 29A and 29B come into contact with each other, and is fastened to the pulley body 13 with a predetermined torque. The fastening of the mounting portion 15 is preferably performed using a jig (not shown) having a protruding portion inserted into the counterbore hole 39, and the fastening torque is preferably managed.
When removing the attachment portion 15 and the vibration isolating rubber sheet 17 from the pulley main body 13, the vibration isolating rubber sheet 17 is also removed by removing the attachment portion 15 from the pulley main body 13. Specifically, the female screw portion 35 of the mounting portion 15 is removed from the male screw portion 31 of the pulley main body 13 by rotating the mounting portion 15 in the direction opposite to that when the mounting portion 15 is attached to the pulley main body 13.

According to the above configuration, since the vibration isolating rubber sheet 17 can be attached to the pulley main body 13 by attaching the attachment portion 15 to the pulley main body 13, the vibration isolating rubber sheet 17 is secured and the number of parts is reduced. Maintainability can be improved.
Since the anti-vibration rubber sheet 17 is sandwiched between the attachment portion 15 and the pulley main body 13, the anti-vibration rubber sheet 17 is attached to the pulley main body 13 by sandwiching the circumferential end thereof. Therefore, the vibration-proof rubber sheet 17 is stably attached to the pulley body 13 without using a plurality of mounting bolts, and the number of parts can be reduced.
Further, since the vibration isolating rubber sheet 17 is fixed to the pulley main body 13 by one mounting portion 15, the vibration isolating rubber sheet 17 can be attached and detached as compared with the method of fixing the sound insulating portion to the pulley main body 13 by a plurality of mounting bolts. The number of man-hours required can be reduced, and maintainability can be improved.

Since the anti-vibration rubber sheet 17 is a rubber sheet formed of rubber that is an elastic member, it is possible to prevent the vibration of the pulley body 13 and the attachment portion 15 from being transmitted to the anti-vibration rubber sheet 17. Therefore, compared with the method of directly attaching the vibration-proof rubber sheet 17 to the pulley main body 13 without using an elastic member, it is possible to ensure sound insulation.
The attaching portion 15 is provided with a holding portion 37 that forms a gap for holding the vibration isolating rubber sheet 17, and the pulley main body 13 and the attaching portion 15 are provided with a regulating surface 29 </ b> A that restricts the gap between the holding portions. 29B is provided, the vibration of the pulley body 13 and the mounting portion 15 can be more reliably prevented from being transmitted to the vibration-proof rubber sheet 17.
When the attachment portion 15 is attached to the pulley body 13, the interval between the holding portions 37 is restricted by the contact of the restriction surfaces 29 </ b> A and 29 </ b> B.
The circumferential portion of the vibration-insulating rubber sheet 17, that is, the portion that comes into contact with the front end surfaces of the holding portion 37 and the male screw portion 31 is made of an elastic material. Since the interval between the holding portion 37 and the front end surface of the male screw portion 31 is regulated to a predetermined interval, the circumferential portion of the vibration isolating rubber sheet 17 is prevented from being excessively compressed, and the vibration isolating rubber sheet It is possible to more reliably prevent the vibrations of the pulley body 13 and the attachment portion 15 from being transmitted to the central portion of 17.

  Since the female screw portion 35 is provided in the attachment portion 15 and the male screw portion 31 is provided in the pulley main body 13, the vibration isolating rubber sheet 17 can be easily attached to and detached from the pulley main body 13. For example, the vibration-insulating rubber sheet 17 can be easily attached to and detached from the pulley body 13 as compared with a method of fixing the vibration-insulating rubber sheet 17 to the pulley body 13 with a plurality of mounting bolts.

Since the anti-vibration rubber sheet 17 is a rubber sheet formed from rubber which is an elastic material, sound insulation can be secured. That is, since the elastic sheet formed of an elastic material is attached to the pulley body 13 so as to cover the fixing bolt 25, noise generated from the fixing bolt 25 can be sound-insulated.
Since the anti-vibration rubber sheet 17 is a rubber sheet formed from rubber, which is an elastic material, the circumferential portion in contact with the pulley body 13 and the mounting portion 15 is formed from an elastic member. Therefore, the vibration-proof rubber sheet 17 can be easily formed as compared with the case where only the circumferential portion is formed of an elastic member.

  As described above, the attaching portion 15 may be provided with the holding portion 37, and the pulley body 13 may be provided with the holding portion 37, and is not particularly limited.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
The basic configuration of the engine of this embodiment is the same as that of the first embodiment, but the configuration of the crank pulley is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the crank pulley will be described with reference to FIG. 4, and description of the engine and the like will be omitted.
FIG. 4 is a partial cross-sectional view illustrating the configuration of the crank pulley according to the present embodiment.
In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and the description is abbreviate | omitted.
As shown in FIG. 4, a crank pulley (pulley) 107 fixed to the crankshaft 5 of the engine 1 includes a pulley body 13 fixed to the crankshaft 5, a mounting portion 15 attached to the pulley body 13, and a pulley body. 13 and an anti-vibration rubber sheet (sound insulating part, elastic member, elastic sheet) 117 disposed between the mounting part 15 and the mounting part 15.

  A plate member (weight member) 119 made of, for example, a metal material such as iron is disposed at the center of the vibration-proof rubber sheet 117. The plate member 119 is formed in a substantially disc shape and is sized to be disposed inside the ring plate portion 33 of the attachment portion 15. Further, the mass of the plate member 119 is determined so that the anti-vibration rubber sheet 117 can insulate the noise generated from the fixing bolt 25 most efficiently. That is, by changing the mass of the plate member 119, it is possible to adjust the sound insulation characteristics of the noise in the vibration-insulating rubber sheet 117. For this reason, the mass of the plate member 119 is adjusted so that the noise generated from the fixing bolt 25 is adjusted to the sound insulation characteristic that makes the most efficient (see FIG. 2).

Next, functions of the engine 1 and the crank pulley 107 in this embodiment will be described.
Since the transmission of the rotational driving force in the engine 1 and the crank pulley 107 is the same as that in the first embodiment, the description thereof is omitted.
Further, the attachment and detachment of the attachment portion 15 and the vibration isolating rubber sheet 117 in the crank pulley 107 are also the same as those in the first embodiment, and the description thereof is omitted.

Next, sound insulation in the crank pulley 107, which is a feature of this embodiment, will be described.
Noise generated from the fixing bolt 25 is transmitted into the pulley body 13 of the crank pulley 107 as shown in FIG. 4 (see FIG. 2). Noise transmitted to the inside of the pulley body 13 is blocked by the anti-vibration rubber sheet 117 disposed at the opening of the pulley body 13 and is prevented from being transmitted from the crank pulley 107 to the outside.
At this time, the anti-vibration rubber sheet 117 is vibrated by noise and vibrates at the center. Since the vibration isolating rubber sheet 117 is provided with the plate member 119, the vibration of the central portion thereof is suppressed, and the generation of noise due to the vibration of the anti vibration isolating rubber sheet 117 is suppressed.

  According to said structure, since the board member 119 is provided in the vibration-proof rubber sheet 117, it can be made easier to ensure sound insulation. That is, by providing the vibration-proof rubber sheet 117 with the plate member 119, the sound insulation characteristics of the vibration-proof rubber sheet 117 can be changed. By setting the mass of the plate member 119 to a predetermined mass, the sound insulation property of the vibration-insulating rubber sheet 117 can be adjusted to a property capable of effectively insulating the noise generated from the fixing bolt 25 to further ensure sound insulation. it can.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG.
The basic configuration of the engine of this embodiment is the same as that of the first embodiment, but the configuration of the crank pulley is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the crank pulley will be described with reference to FIG. 5, and the description of the engine and the like will be omitted.
FIG. 5 is a partial cross-sectional view illustrating the configuration of the crank pulley according to the present embodiment.
In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and the description is abbreviate | omitted.
As shown in FIG. 5, the crank pulley (pulley) 207 fixed to the crankshaft 5 of the engine 1 includes a pulley main body 13 fixed to the crankshaft 5, a mounting portion 15 attached to the pulley main body 13, and a pulley main body. 13 and a sound insulation part 217 disposed between the attachment part 15 (see FIG. 2).

The sound insulating part 217 includes a disc part (plate member) 219 that insulates noise generated from the fixing bolt 25, and a vibration isolating part (elastic member) 221 provided at the circumferential end of the disc part 219. (See FIG. 2).
The disk part 219 is a disk-shaped member formed from, for example, a metal material. The vibration isolator 221 is formed from an elastic member such as silicon rubber or butyl rubber, and is disposed so as to cover the end of the disc portion 219.

Next, functions of the engine 1 and the crank pulley 207 in the present embodiment will be described.
Since the transmission of the rotational driving force in the engine 1 and the crank pulley 207 is the same as that in the first embodiment, the description thereof is omitted.
Further, the attachment / detachment of the attachment portion 15 and the vibration isolation portion 217 to / from the crank pulley 207 is the same as that in the first embodiment, and thus the description thereof is omitted.

Next, sound insulation in the crank pulley 207, which is a feature of the present embodiment, will be described.
Noise generated from the fixing bolt 25 is transmitted into the pulley body 13 of the crank pulley 207 as shown in FIG. 5 (see FIG. 2). Noise transmitted to the inside of the pulley body 13 is blocked by the disk portion 219 of the sound insulating portion 217 disposed at the opening of the pulley body 13 and is prevented from being transmitted from the crank pulley 207 to the outside.
On the other hand, the vibration transmitted from the fixing bolt 25 or the crankshaft 5 to the pulley body 13 is also transmitted to the attachment portion 15. The vibration transmitted to the pulley body 13 and the mounting portion 15 is transmitted from the tip of the male screw portion 31 and the holding portion 37 to the vibration isolating portion 221 of the sound insulating portion 217. When the vibration is transmitted to the vibration isolator 221, the vibration is attenuated by the elasticity of the vibration isolator 221, and the vibration is prevented from being transmitted to the disk portion 219.
The thickness of the vibration isolator 221 (the length in the left-right direction in FIG. 5) is formed so as to be thicker than the distance between the front end surface of the male screw portion 31 and the holding portion 37, and The thickness of the oscillating portion 221 is formed so as not to be thicker than a predetermined value with respect to the interval.

According to said structure, since the sound insulation part 217 is provided with the disc part 219 formed from the metal material, and the vibration isolator 221 provided in the edge part of the disc part 219, it can ensure sound insulation. it can. That is, since the disc portion 219 is attached to the pulley main body 13 so as to cover the fixing bolt 25, noise generated from the fixing bolt 25 can be insulated.
The vibration isolator 221 is provided at the edge of the disc part 219, and the vibration isolator 221 is in contact with the pulley body 13 and the attachment part 15. Therefore, vibration transmitted from the pulley main body 13 and the attachment portion 15 can be blocked by the vibration isolation portion 221 and can be prevented from being transmitted to the disc portion 219.
Since the vibration isolator 221 is provided only at the edge of the disc part 219, the amount of elastic member such as rubber in the sound insulating part 217 can be reduced.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG.
The basic configuration of the engine of this embodiment is the same as that of the first embodiment, but the configuration of the crank pulley is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the crank pulley will be described with reference to FIG. 6, and description of the engine and the like will be omitted.
FIG. 6 is a partial cross-sectional view illustrating the configuration of the crank pulley according to the present embodiment.
In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and the description is abbreviate | omitted.
As shown in FIG. 6, the crank pulley (pulley) 307 fixed to the crankshaft 5 of the engine 1 includes a pulley main body 313 fixed to the crankshaft 5, a mounting portion 315 attached to the pulley main body 313, and a pulley main body. The anti-vibration rubber sheet 17 is provided between 313 and the attachment portion 315 (see FIG. 2).

The pulley body 313 is formed in a bottomed cylindrical shape having a bottom surface 19 and a cylindrical portion 321.
The cylindrical portion 321 of the pulley body 313 includes a belt groove 27, a regulation surface 329A that contacts the regulation surface 329B of the attachment portion 315, and a female screw portion 331 that is screwed into the male screw portion 335 of the attachment portion 315. Is provided. The restriction surface 329 </ b> A is a flat surface formed adjacent to the inner peripheral side of the female screw portion 331, and is a substantially ring-shaped flat surface that is substantially perpendicular to the central axis C of the crankshaft 5. An anti-vibration rubber sheet 17 is disposed in the inner peripheral region of the regulation surface 329A. The female screw portion 331 is a substantially cylindrical protruding portion provided on the outer peripheral side of the opening side (left side in FIG. 6) of the pulley main body 313. On the inner peripheral surface of the female screw portion 331, a screw thread that is screwed with the screw thread of the male screw portion 335 is formed.

The attaching portion 315 is attached to the pulley main body 313, and attaches the anti-vibration rubber sheet 17 to the pulley main body 313 by sandwiching the anti-vibration rubber sheet 17 between the pulley main body 313. Examples of the material for forming the attachment portion 315 include iron-based materials such as stainless steel.
The attachment portion 315 includes a ring plate portion 333 that sandwiches the vibration isolating rubber sheet 17 between the pulley main body 313, and a male screw portion 331 that is screwed with the female screw portion 331 of the pulley main body 313 on the outer peripheral surface of the ring plate portion 333. A screw portion 335 is formed.

In the ring plate portion 333, a holding portion 37 and a regulating surface 329B are formed on one surface (the right surface in FIG. 6) facing the pulley body 313, and the other surface (the left surface in FIG. 6). ) Has a counterbore hole 39 formed therein.
The holding portion 37 is an annularly concave surface formed on the inner peripheral side of one surface of the ring plate portion 333, and on the other surface side (the left side in FIG. 6) toward the radially inner peripheral side. It is a concave surface. The anti-vibration rubber sheet 17 is sandwiched and held between the regulation surface 329 </ b> A and the holding portion 37.
The restriction surface 329 </ b> B is a flat surface formed on the outer peripheral side of one surface of the ring plate portion 333, and is a flat surface that is substantially perpendicular to the central axis C of the crankshaft 5. The contact between the regulation surface 329A and the regulation surface 329B keeps the distance between the regulation surface 329A and the holding portion 37 at a predetermined distance.

Next, functions of the engine 1 and the crank pulley 207 in the present embodiment will be described.
Since the transmission of the rotational driving force in the engine 1 and the crank pulley 207 is the same as that in the first embodiment, the description thereof is omitted.
Since the sound insulation in the crank pulley 207 is the same as in the first embodiment, the description thereof is omitted.

The attachment / detachment of the attachment portion 15 and the vibration isolating rubber sheet 17 in the crank pulley 207 will be described.
When the attachment portion 315 and the vibration isolating rubber sheet 17 are attached to the pulley main body 313, the vibration isolating rubber sheet 17 is disposed between the pulley main body 313 and the attachment portion 315 as shown in FIG. The mounting portion 315 is screwed onto the screw.
Specifically, the anti-vibration rubber sheet 17 is disposed so as to be sandwiched between the regulation surface 329A of the pulley main body 313 and the holding portion 37 of the attachment portion 315. Then, the female screw portion 331 of the pulley body 313 and the male screw portion 335 of the attachment portion 315 are screwed together. The attachment portion 315 is attached to the pulley body 313 so that the regulation surfaces 329A and 329B come into contact with each other, and is fastened to the pulley body 313 with a predetermined torque. The tightening of the attachment portion 315 is preferably performed using a jig (not shown) having a protruding portion inserted into the counterbore hole 39, and the tightening torque is preferably managed.
When removing the attachment portion 315 and the vibration isolating rubber sheet 17 from the pulley main body 313, the vibration isolating rubber sheet 17 is also removed by removing the attachment portion 315 from the pulley main body 313. Specifically, the male screw portion 335 of the attachment portion 315 is removed from the female screw portion 331 of the pulley main body 313 by rotating the attachment portion 315 in the direction opposite to that when the attachment portion 315 is attached to the pulley main body 313.

According to the above configuration, since the female screw portion 331 is provided in the attachment portion 315 and the male screw portion 335 is provided in the pulley main body 313, the vibration isolating rubber sheet 17 can be easily attached to and detached from the pulley main body 313. Can do.
The female threaded portion 331 of the mounting portion 315 and the male threaded portion 335 of the pulley body 313 are relatively rotated in one rotational direction to attach the mounting portion 315 to the pulley body 313, and the vibration-proof rubber sheet 17 is attached to the pulley body 313. Can be attached. On the other hand, the attachment part 315 can be removed from the pulley body 313 and the vibration-proof rubber sheet 17 can be removed from the pulley body 313 by relatively rotating the female thread part 331 and the male thread part 335 in other rotational directions.
Therefore, the soundproof rubber sheet 17 can be easily attached to and detached from the pulley body 313 as compared with the method of fixing the soundproof rubber sheet 17 to the pulley body 313 with a plurality of mounting bolts.

  Since the female threaded portion 331 is provided on the pulley body 313, the thread of the female threaded portion 331 is not exposed to the outer peripheral surface when the mounting portion 315 is removed from the pulley body 313, and the pulley body 313 is handled. Becomes easy.

[First Modification of Fourth Embodiment]
Next, a first modification of the fourth embodiment of the present invention will be described with reference to FIG.
The basic configuration of the engine of this modification is the same as that of the fourth embodiment, but the configuration of the crank pulley is different from that of the fourth embodiment. Therefore, in this embodiment, only the periphery of the crank pulley will be described with reference to FIG. 7, and the description of the engine and the like will be omitted.
FIG. 7 is a partial cross-sectional view illustrating the configuration of a crank pulley according to this modification.
In addition, the same code | symbol is attached | subjected to the component same as 4th Embodiment, and the description is abbreviate | omitted.
As shown in FIG. 7, a crank pulley (pulley) 407 fixed to the crankshaft 5 of the engine 1 includes a pulley main body 313 fixed to the crankshaft 5, an attachment portion 315 attached to the pulley main body 313, and a pulley main body. The anti-vibration rubber sheet 117 is provided between 313 and the attachment portion 315 (see FIG. 2).

  A plate member 119 made of a metal material such as iron, for example, is disposed at the center of the anti-vibration rubber sheet 117. The plate member 119 is formed in a substantially disk shape and is sized so as to be disposed inside the attachment portion 315. Further, the mass of the plate member 119 is determined so that the anti-vibration rubber sheet 117 can insulate the noise generated from the fixing bolt 25 most efficiently. That is, by changing the mass of the plate member 119, it is possible to adjust the sound insulation characteristics of the noise in the vibration-insulating rubber sheet 117. For this reason, the mass of the plate member 119 is adjusted so that the noise generated from the fixing bolt 25 is adjusted to the sound insulation characteristic that makes the noise most efficient (see FIG. 2).

Next, functions of the engine 1 and the crank pulley 407 in the present embodiment will be described.
Since the transmission of the rotational driving force in the engine 1 and the crank pulley 407 is the same as in the first embodiment, the description thereof is omitted.
Further, the attachment and detachment of the attachment portion 315 and the anti-vibration rubber sheet 117 in the crank pulley 407 are also the same as those in the fourth embodiment, and thus description thereof is omitted.

Next, sound insulation in the crank pulley 407, which is a feature of this embodiment, will be described.
Noise generated from the fixing bolt 25 is transmitted into the pulley body 313 of the crank pulley 407 as shown in FIG. 7 (see FIG. 2). Noise transmitted to the inside of the pulley body 313 is blocked by the anti-vibration rubber sheet 117 disposed at the opening of the pulley body 313 and is prevented from being transmitted from the crank pulley 107 to the outside.
At this time, the anti-vibration rubber sheet 117 is vibrated by noise and vibrates at the center. Since the vibration isolating rubber sheet 117 is provided with the plate member 119, the vibration of the central portion thereof is suppressed, and the generation of noise due to the vibration of the anti vibration isolating rubber sheet 117 is suppressed.

  According to said structure, since the board member 119 is provided in the vibration-proof rubber sheet 117, it can be made easier to ensure sound insulation. That is, by providing the vibration-proof rubber sheet 117 with the plate member 119, the sound insulation characteristics of the vibration-proof rubber sheet 117 can be changed. By setting the mass of the plate member 119 to a predetermined mass, the sound insulation property of the vibration-insulating rubber sheet 117 can be adjusted to a property capable of effectively insulating the noise generated from the fixing bolt 25 to further ensure sound insulation. it can.

[Second Modification of Fourth Embodiment]
Next, a second modification of the fourth embodiment of the present invention will be described with reference to FIG.
The basic configuration of the engine of this modification is the same as that of the fourth embodiment, but the configuration of the crank pulley is different from that of the fourth embodiment. Therefore, in this embodiment, only the periphery of the crank pulley will be described with reference to FIG. 8, and description of the engine and the like will be omitted.
FIG. 8 is a partial cross-sectional view illustrating the configuration of a crank pulley according to this modification.
In addition, the same code | symbol is attached | subjected to the component same as 4th Embodiment, and the description is abbreviate | omitted.
As shown in FIG. 8, a crank pulley (pulley) 507 fixed to the crankshaft 5 of the engine 1 includes a pulley main body 313 fixed to the crankshaft 5, a mounting portion 315 attached to the pulley main body 313, and a pulley main body. 313 and a sound insulation part 217 disposed between the attachment part 315 (see FIG. 2).

The sound insulation part 217 includes a disc part 219 that insulates noise generated from the fixing bolt 25, and a vibration isolation part 221 provided at the circumferential end of the disc part 219 (see FIG. 2).
The disk part 219 is a disk-shaped member formed from, for example, a metal material. The vibration isolator 221 is formed from an elastic member such as silicon rubber or butyl rubber, and is disposed so as to cover the end of the disc portion 219.

Next, functions of the engine 1 and the crank pulley 507 in the present embodiment will be described.
Since the transmission of the rotational driving force in the engine 1 and the crank pulley 507 is the same as in the first embodiment, the description thereof is omitted.
Further, the attachment and detachment of the attachment portion 315 and the vibration isolating portion 217 in the crank pulley 507 are the same as those in the fourth embodiment, and thus description thereof is omitted.

Next, sound insulation in the crank pulley 507, which is a feature of the present embodiment, will be described.
The noise generated from the fixing bolt 25 is transmitted into the pulley body 313 of the crank pulley 507 as shown in FIG. 8 (see FIG. 2). Noise transmitted into the pulley main body 313 is blocked by the disk portion 219 of the sound insulating portion 217 disposed in the opening of the pulley main body 313 and is prevented from being transmitted from the crank pulley 507 to the outside.
On the other hand, the vibration transmitted from the fixing bolt 25 or the crankshaft 5 to the pulley main body 313 is also transmitted to the mounting portion 315. The vibration transmitted to the pulley main body 313 and the attachment portion 315 is transmitted from the regulation surface 329A and the holding portion 37 to the vibration isolation portion 221 of the sound insulation portion 217. When the vibration is transmitted to the vibration isolator 221, the vibration is attenuated by the elasticity of the vibration isolator 221, and the vibration is prevented from being transmitted to the disk portion 219.
The thickness of the vibration isolator 221 (the length in the left-right direction in FIG. 8) is formed so as to be thicker than the interval between the regulating surface 329A and the holding unit 37, and the vibration isolator 221 The thickness is formed so as not to be thicker than a predetermined value with respect to the interval.

According to said structure, since the sound insulation part 217 is provided with the disc part 219 formed from the metal material, and the vibration isolator 221 provided in the edge part of the disc part 219, it can ensure sound insulation. it can. That is, since the disc portion 219 is attached to the pulley main body 313 so as to cover the fixing bolt 25, noise generated from the fixing bolt 25 can be insulated.
The vibration isolator 221 is provided at the edge of the disk portion 219, and the vibration isolator 221 is in contact with the pulley body 313 and the attachment portion 315. Therefore, vibration transmitted from the pulley main body 313 and the attachment portion 315 can be blocked by the vibration isolation portion 221 and can be prevented from being transmitted to the disc portion 219.
Since the vibration isolator 221 is provided only at the edge of the disc part 219, the amount of elastic member such as rubber in the sound insulating part 217 can be reduced.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described with reference to FIG.
The basic configuration of the engine of this embodiment is the same as that of the first embodiment, but the configuration of the crank pulley is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the crank pulley will be described with reference to FIG. 9, and the description of the engine and the like will be omitted.
FIG. 9 is a partial cross-sectional view illustrating the configuration of the crank pulley according to the present embodiment.
In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and the description is abbreviate | omitted.
As shown in FIG. 9, a crank pulley (pulley) 607 fixed to the crankshaft 5 of the engine 1 includes a pulley main body 13 fixed to the crankshaft 5, an attachment portion 15 attached to the pulley main body 13, and a pulley main body. 13 and an anti-vibration rubber sheet 17 disposed between the mounting portion 15 and a sound absorbing member 609 disposed in the pulley body 13.
The sound absorbing member 609 is formed of a porous member such as a sponge and absorbs noise generated from the fixing bolt 25. The sound absorbing member 609 is disposed in a space surrounded by the pulley body 13 and the vibration isolating rubber sheet 17 (see FIG. 2).

Next, functions of the engine 1 and the crank pulley 607 in the present embodiment will be described.
Since the transmission of the rotational driving force in the engine 1 and the crank pulley 607 is the same as in the first embodiment, the description thereof is omitted.
Further, the attachment and detachment of the attachment portion 15 and the vibration isolating rubber sheet 17 in the crank pulley 607 are also the same as those in the first embodiment, and the description thereof is omitted.

Next, sound insulation in the crank pulley 607, which is a feature of this embodiment, will be described.
The noise generated from the fixing bolt 25 is transmitted into the pulley body 13 of the crank pulley 607 as shown in FIG. 9 (see FIG. 2). Part of the noise transmitted into the pulley body 13 is absorbed by the sound absorbing member 609, and the remaining noise is blocked by the anti-vibration rubber sheet 17 disposed in the opening of the pulley body 13, so that the noise is transmitted to the outside from the crank pulley 607. It is prevented from being transmitted.

  According to said structure, it becomes easy to ensure sound-insulating property by arrange | positioning the sound-absorbing member 609 between the pulley main body 13 and the vibration-proof rubber sheet 17. That is, as compared with the case where nothing is arranged between the pulley body 13 and the vibration isolating rubber sheet 17, the noise generated from the fixing bolt 25 due to the sound absorbing member 609 absorbing the noise causes the pulley main body 13 and the vibration isolating rubber sheet to be generated. It is possible to prevent reverberation in the space between the two, and it is easier to ensure sound insulation.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described with reference to FIGS.
The basic configuration of the engine of this embodiment is the same as that of the first embodiment, but the configuration of the crank pulley is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the crank pulley will be described with reference to FIGS. 10 to 13, and the description of the engine and the like will be omitted.
FIG. 10 is a partial cross-sectional view illustrating the configuration of the crank pulley according to the present embodiment.
In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and the description is abbreviate | omitted.
As shown in FIG. 10, a crank pulley (pulley) 707 fixed to the crankshaft 5 of the engine 1 includes a pulley body 713 fixed to the crankshaft 5, a mounting portion 715 attached to the pulley body 713, and a pulley body. And an anti-vibration rubber sheet (sound insulation part, elastic member, elastic sheet) 717 disposed between the reference numeral 713 and the attachment part 715.

The pulley body 713 is formed in a bottomed cylindrical shape having a bottom surface 19 and a cylindrical portion 721.
The cylindrical portion 721 of the pulley body 713 includes a belt groove 27, a regulation surface 729 </ b> A that contacts the regulation surface 729 </ b> B of the attachment portion 715, and a female screw portion 731 that is screwed with the male screw portion 735 of the attachment portion 715. Is provided. The restriction surface 729 </ b> A is a flat surface formed on the inner peripheral side of the female screw portion 731, and is a substantially ring-shaped flat surface that is substantially perpendicular to the central axis C of the crankshaft 5. The female screw portion 731 is a substantially cylindrical protruding portion provided on the outer peripheral side of the opening side (left side in FIG. 10) of the pulley main body 713. On the inner peripheral surface of the female screw portion 731, a screw thread that is screwed with the screw thread of the male screw portion 735 is formed. An anti-vibration rubber sheet 717 is disposed on the front end surface (left end surface) of the female screw portion 731.

The attachment portion 715 is attached to the pulley main body 713, and the vibration-proof rubber sheet 717 is attached to the pulley main body 713 by sandwiching the vibration-proof rubber sheet 717 between the pulley main body 713. Examples of the material for forming the attachment portion 715 include iron-based materials such as stainless steel.
The attachment portion 715 includes a ring plate portion 733 that sandwiches the vibration-proof rubber sheet 717 between the pulley main body 713 and a male screw portion 735 that is screwed with the female screw portion 731 of the pulley main body 713.
In the ring plate portion 733, a holding surface (holding portion) 737 is formed on one surface (the right side surface in FIG. 10) facing the pulley body 713.
The holding surface 737 is an annular surface formed on the outer peripheral side of one surface of the ring plate portion 733. The anti-vibration rubber sheet 717 is sandwiched and held between the front end surface of the female screw portion 731 and the holding surface 737.

FIG. 11 is a rear view illustrating the configuration of the attachment portion 715 of FIG.
As shown in FIGS. 10 and 11, the male screw portion 735 is four protrusions extending from the outer peripheral side of one surface of the ring plate portion 733 to the pulley body 713 side (right side in FIG. 10). The four male screw portions 735 are arranged at equal intervals on the same circumference. On the inner peripheral surface of the male screw portion 735, a screw thread to be screwed with the screw thread of the female screw portion 731 is formed. A regulation surface 729 </ b> B that contacts the regulation surface 729 </ b> A of the pulley body 713 is formed at the distal end portion (right end portion in FIG. 10) of the male screw portion 735. The restriction surface 729 </ b> B is a plane that is substantially perpendicular to the central axis C of the crankshaft 5. Since the regulation surface 729A and the regulation surface 729B are in contact with each other, the distance between the front end surface of the female screw portion 731 and the holding surface 737 is maintained at a predetermined distance.
The number of male screw portions 735 may be four as described above, may be three, may be five or more, and is not particularly limited.

FIG. 12 is a front view illustrating the configuration of the vibration-proof rubber sheet 717 of FIG.
As shown in FIGS. 10 and 12, the anti-vibration rubber sheet 717 is a rubber sheet formed in a disk shape and insulates noise generated from the fixing bolt 25.
Examples of the rubber forming the vibration-proof rubber sheet 717 include silicon rubber and butyl rubber, and other known rubbers may be used and are not particularly limited.
The anti-vibration rubber sheet 717 is formed with a through hole 718 through which the male screw portion 735 is inserted. The anti-vibration rubber sheet 717 is formed so that the thickness thereof is at least thicker than the distance between the front end surface of the female screw portion 731 and the holding surface 737 at the circumferential portion that contacts the pulley body 713 and the mounting portion 715. ing. By doing so, the anti-vibration rubber sheet 717 can be reliably held between the female screw portion 731 and the holding surface 737. Further, the thickness of the circumferential portion of the vibration-proof rubber sheet 717 is formed so as not to be thicker than a predetermined value with respect to the interval. By doing in this way, it can prevent that the vibration isolating rubber sheet 717 is compressed too much in the said circumference part. By preventing over-compression, it is possible to prevent the vibrations of the pulley main body 713 and the attachment portion 715 from being transmitted to the central portion of the vibration-proof rubber sheet 717.

Next, functions of the engine 1 and the crank pulley 707 in the present embodiment will be described.
Since the transmission of the rotational driving force in the engine 1 and the crank pulley 707 is the same as that in the first embodiment, the description thereof is omitted.

Next, sound insulation in the crank pulley 707, which is a feature of this embodiment, will be described.
Noise generated from the fixing bolt 25 is transmitted into the pulley body 713 of the crank pulley 707. Noise transmitted to the inside of the pulley body 713 is blocked by the anti-vibration rubber sheet 717 disposed at the opening of the pulley body 713 and is prevented from being transmitted from the crank pulley 707 to the outside.
On the other hand, the vibration transmitted from the fixing bolt 25 or the crankshaft 5 to the pulley body 713 is also transmitted to the mounting portion 715. The vibration transmitted to the pulley body 713 and the mounting portion 715 is transmitted from the tip of the female screw portion 731 and the holding surface 737 to the circumferential portion of the vibration-proof rubber sheet 717. When the vibration is transmitted to the circumferential portion of the vibration-proof rubber sheet 717, the vibration is attenuated by the elasticity of the vibration-proof rubber sheet 717, and the vibration is prevented from being transmitted to the central portion of the vibration-proof rubber sheet 717.

The attachment / detachment of the attachment portion 715 and the vibration isolating rubber sheet 717 in the crank pulley 707 will be described.
When attaching the mounting portion 715 and the vibration isolating rubber sheet 717 to the pulley main body 713, as shown in FIG. 10, the vibration isolating rubber sheet 717 is disposed between the pulley main body 713 and the mounting portion 715, and the pulley main body 713. The mounting portion 715 is screwed onto the screw.
Specifically, the male screw portion 735 of the attachment portion 715 is inserted into the through hole 718 of the vibration-proof rubber sheet 717, and the female screw portion 731 of the pulley body 713 and the male screw portion 735 of the attachment portion 715 are screwed together. The attachment portion 715 is attached to the pulley body 713 so that the regulation surfaces 729A and 729B come into contact with each other, and is fastened to the pulley body 713 with a predetermined torque.
When removing the attachment portion 715 and the vibration isolating rubber sheet 717 from the pulley main body 713, the vibration isolating rubber sheet 717 is also removed by removing the attachment portion 715 from the pulley main body 713. Specifically, the male screw portion 735 of the attachment portion 715 is removed from the female screw portion 731 of the pulley main body 713 by rotating the attachment portion 715 in the direction opposite to that when the attachment portion 715 is attached to the pulley main body 713.

  According to said structure, since the vibration proof rubber sheet 717 with a large area can be used, the sound insulation in the crank pulley 707 is securable.

FIG. 13 is a partial sectional view for explaining another embodiment of the crank pulley of FIG.
As described above, the inner peripheral surface of the attachment portion 715 may be formed substantially in parallel with the central axis C, or as shown in FIG. 13, the outer periphery in the radial direction toward the direction away from the crank pulley 707. It may be formed so as to be inclined toward the side, and is not particularly limited. By doing in this way, the area of the attaching part 715 can be made small.

It is a mimetic diagram explaining composition of an engine concerning a 1st embodiment of the present invention. It is a fragmentary sectional view explaining the structure of the crank pulley of FIG. It is a front view explaining the structure of the attaching part of FIG. It is a fragmentary sectional view explaining the composition of the crank pulley concerning a 2nd embodiment of the present invention. It is a fragmentary sectional view explaining the composition of the crank pulley concerning a 3rd embodiment of the present invention. It is a fragmentary sectional view explaining the composition of the crank pulley concerning a 4th embodiment of the present invention. It is a fragmentary sectional view explaining the composition of the crank pulley concerning the 1st modification of the 4th embodiment of the present invention. It is a fragmentary sectional view explaining the composition of the crank pulley concerning the 2nd modification of the 4th embodiment of the present invention. It is a fragmentary sectional view explaining the composition of the crank pulley concerning a 5th embodiment of the present invention. It is a fragmentary sectional view explaining the composition of the crank pulley concerning a 6th embodiment of the present invention. It is a rear view explaining the structure of the attaching part 715 of FIG. It is a front view explaining the structure of the vibration-proof rubber sheet 717 of FIG. It is a fragmentary sectional view explaining another Example of the crank pulley of FIG.

Explanation of symbols

1 Engine 5 Crankshaft (Rotating shaft)
7, 107, 207, 307, 407, 507, 607, 707 Crank pulley (pulley)
9 Generator (auxiliary machine)
11 Belt 13,313,713 Pulley body 15,315,715 Mounting portion 17,117,717 Anti-vibration rubber sheet (sound insulation portion, elastic member, elastic sheet)
25 Fixing bolts 29A, 29B, 329A, 329B, 729A, 729B Restricting surfaces 31, 335, 735 Male threaded portions 35, 331, 731 Female threaded portions 37 Holding portions 119 Plate member (weight member)
217 Sound insulation part 219 Disc part (plate member)
221 Vibration isolator (elastic member)
609 Sound absorbing member 737 Holding surface (holding portion)

Claims (8)

A pulley body fixed to the rotating shaft using a fixing bolt;
A sound insulating part attached to the pulley body so as to cover the fixing bolt;
An attachment portion that is attached to the pulley body and sandwiches the sound insulation portion between the pulley body,
The sound insulation portion includes an elastic member made of an elastic material at least in a portion in contact with the pulley main body and the attachment portion,
At least one of the pulley main body and the attachment portion is provided with a holding portion that forms a gap in which the sound insulating portion is held,
The pulley main body and the attachment portion are provided with a regulation surface that regulates a gap interval in the holding portion to a predetermined interval by contacting each other. The mounting portion is provided with a female screw portion having a thread formed on the inner peripheral surface,
The pulley according to claim 1, wherein the pulley main body is provided with a male screw portion having a thread formed on an outer peripheral surface thereof to be screwed with the female screw portion. A male screw portion is formed on the outer peripheral surface of the mounting portion,
The pulley according to claim 1, wherein the pulley main body is provided with a female screw portion having a screw thread formed on an inner peripheral surface thereof to be screwed with the male screw portion.   The pulley according to any one of claims 1 to 3, wherein the sound insulating portion is an elastic sheet formed of an elastic material.   The pulley according to claim 1, wherein a weight member is provided on the elastic sheet in the sound insulating portion.   The pulley according to any one of claims 1 to 3, wherein the sound insulating portion includes a plate member formed of a metal material and an elastic member provided at an edge portion of the plate member. A pulley body fixed to the rotating shaft using a fixing bolt;
A sound insulating part attached to the pulley body so as to cover the fixing bolt;
And a sound absorbing member disposed between the pulley main body and the sound insulating portion. A rotating shaft for transmitting rotational driving force;
An engine including a pulley fixed to the rotating shaft using a fixing bolt and transmitting a rotational driving force of the rotating shaft to an auxiliary machine via a belt,
The engine according to any one of claims 1 to 7, wherein the pulley is the pulley according to any one of claims 1 to 7.

Images