JP2003269538A - Viscous-type damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a viscous-type damper excellent in friction resistance and durability by reducing friction coefficients of a sliding part. <P>SOLUTION: This viscous-type damper 1 is fixed to one end of a crankshaft 11 of an engine. Side sliding bodies 5 are installed on a face perpendicular to the crankshaft 11 of an inertia ring 3, and inner peripheral sliding bodies 6 are installed on faces corresponding to the inside diameter of the inertia ring 3 inside a housing 2. An amorphous carbon membrane 7 is formed on the end faces of the side sliding bodies 5 and the surfaces of the inner peripheral sliding bodies 6. Because the amorphous carbon membrane 7 has a low friction coefficient, a friction coefficient between the inertia ring 3 and the housing 2 is reduced when the viscous-type damper 1 absorbs torsion vibrations of the crankshaft 11, so as to improve friction resistance and durability. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a viscous damper that reduces torsional vibration of a rotary shaft.

[0002]

BACKGROUND ART When a rotating shaft undergoes fluctuations in the rotating speed, the rotating shaft may be twisted. For example, a disk-shaped flywheel is provided at one end of a crankshaft of an engine in order to suppress fluctuations in rotation due to a piston and obtain smooth rotation. However, when the rotation speed of the crankshaft fluctuates abruptly, the inertial force of the flywheel causes twisting of the crankshaft, which causes engine vibration. Therefore, in order to prevent such torsional vibration, a damper is generally provided at the end of the crankshaft opposite to the flywheel.

An example of such a damper is a viscous damper. This viscous damper includes an annular housing and a rotatable inertia ring inside the housing, and a viscous fluid such as silicone oil is filled between the housing and the inertia ring. When there is a change in the rotational speed of the crankshaft, the inertia ring slides inside the housing via the viscous fluid due to the inertial force, thereby exerting the same effect as that of the flywheel. Thus, the flywheel and the viscous damper act on both ends of the crankshaft to absorb the torsional vibration of the crankshaft.

[0004]

In the above-described viscous damper, the inertia ring slides inside the housing, so that the outer surface of the inertia ring and the inner surface of the housing have sliding surfaces that slide with the rotation of the viscous damper. Become. In particular, when the engine is started, the inertia ring is in contact with the housing due to gravity, so that the sliding surfaces may directly contact each other and generate heat due to friction, and this heat generation may cause thermal deterioration of the viscous fluid. In addition, wear powder from the sliding surface caused by friction mixes into the viscous fluid with long-term use. Due to the phenomenon described above, the performance of the viscous damper deteriorates after a certain period of use, and when the performance reaches a predetermined set value, the life of the viscous damper is reached.

When the performance of the viscous damper deteriorates, the torsional vibration of the crankshaft cannot be sufficiently absorbed, and the torsional vibration may adversely affect the crankshaft. Therefore, it is necessary to remove the viscous damper from the crankshaft and replace it before the life of the viscous damper. Therefore, if the life of the viscous damper is short, frequent maintenance is required, and in order to reduce the maintenance cost, it is desired to further extend the life of the viscous damper.

An object of the present invention is to provide a viscous damper which has a reduced friction coefficient at the sliding portion and is excellent in wear resistance and durability.

[0007]

A viscous damper according to claim 1 of the present invention comprises an annular housing attached to a rotary shaft, an inertia ring rotatably provided inside the housing, and a housing. A viscous fluid filled inside is provided, and an amorphous carbon film is provided on at least a part of a sliding surface between the housing and the inertia ring.

In the present invention having this structure, since the amorphous carbon film having a low friction coefficient is provided on the sliding surface, the friction coefficient of the sliding surface is reduced, heat generation is suppressed, and the heat of the viscous fluid is reduced. Deterioration is reduced. Further, as a result, wear on the sliding surface is reduced, wear particles are less likely to be generated, and durability of the viscous damper is improved. Here, amorphous carbon (diamond-like carbon, DLC, Diamond Like Carbon) is a material having an amorphous structure having both a diamond structure and a graphite structure. It has excellent smoothness, has a particularly low coefficient of friction among various coating materials, and has a low opponent attack property, and can form a film on resin, rubber, etc. in addition to metals, ceramics, etc.
The film is formed by ionization deposition or high frequency plasma CVD (Che
mical vapor deposition (chemical vapor deposition) method, arc type ion plating method, etc.

A viscous damper according to a second aspect of the present invention is the viscous damper according to the first aspect, in which both the housing and the inertia ring are formed in a substantially quadrangular shape in cross section, and a plane orthogonal to the axis of rotation is orthogonal to the axis of rotation. And at least one of the four surfaces of the inner surface of the housing and the outer surface of the inertia ring is a sliding surface. In the present invention having this configuration, since the housing and the inertia ring have substantially rectangular cross sections, for example, when the rotating shaft is arranged horizontally or vertically, the sliding surface slides uniformly over the entire surface, preventing concentrated wear. Wear resistance is improved.

A viscous damper according to a third aspect of the present invention is the viscous damper according to the second aspect, wherein at least one of the housing and the inertia ring is provided with a sliding body on a plane orthogonal to the axis, and the sliding body forms an axis orthogonal to the sliding body. A sliding surface is formed, and an amorphous carbon film is provided on at least the sliding surface of the sliding body. In the present invention having this structure, since the sliding surface is formed on the sliding body provided on the axis-perpendicular surface and the amorphous carbon film is provided on the sliding surface, the sliding body is made of an amorphous material during manufacturing. The carbon film may be incorporated into the viscous damper after it is formed, and the manufacturing is easy.
Further, if the sliding body is made small, it can be manufactured at low cost, the sliding surface becomes small, the friction during rotation is further reduced, and the durability is further improved. In particular, when the rotation axis is provided vertically and the viscous damper is arranged with the axis-orthogonal surface facing downward, the surface becomes the surface most susceptible to friction, and the present invention having this configuration is useful.

A viscous damper according to claim 4 of the present invention is the viscous damper according to claim 2 or 3, wherein at least an inner diameter of the inertia ring and a surface of the inner surface of the housing corresponding to the inner diameter of the inertia ring. A strip-shaped sliding body is provided on one side, and this sliding body forms a sliding surface between the inner diameter of the inertia ring and the inner surface of the housing corresponding to the inner diameter of the inertia ring, and at least the sliding surface of the sliding body is amorphous. It is characterized in that a high quality carbon film is provided. In the present invention having this configuration, since the slide body is provided on at least one of the inner diameter of the inertia ring and the surface corresponding to the inertia ring on the inner surface of the housing, when the rotation shaft is horizontally arranged, that portion is gravitated. Is the most sliding part.
Since the amorphous carbon film is provided on the sliding surface of this portion, the coefficient of friction is effectively reduced and the durability is improved. Further, since the sliding body is composed of the belt-shaped member, it is sufficient to form the amorphous carbon film on the belt-shaped sliding body and then incorporate it into at least one of the housing and the inertia ring at the time of manufacturing, which facilitates the manufacturing. This facilitates the formation of a coating on the inner surface of the housing or on the inner ring of the inertia ring where it is difficult to form a coating.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing a part of the engine 10 of this embodiment. In this figure, an engine 10 is provided with a plurality of cylinders and pistons (not shown) inside, and a crankshaft 11 as a rotary shaft that converts reciprocating motions of these pistons into rotary motions.
Is equipped with. The piston is rotatably attached to a horizontally arranged crankshaft 11, and a disk-shaped flywheel 12 is provided at one end of the crankshaft 11 in order to suppress fluctuations in rotation due to the piston and obtain smooth rotation. It is provided. Further, the other end of the crankshaft 11 is provided with a viscous damper 1 according to the present invention in order to absorb the torsional vibration of the crankshaft 11 due to the inertial force of the flywheel 12.

As shown in FIG. 2, the viscous damper 1 has an annular housing 2 fixed to a crankshaft 11, an inertial ring 3 rotatably provided inside the housing 2, and a housing 2 filled with the inertial ring 3. And viscous fluid 4 that has been generated. The housing 2 is made of metal such as cast iron, steel and aluminum, engineering plastic such as fiber reinforced plastic (FRP), and other materials, and is fixed to the other end of the crankshaft 11 by a fixing portion 2.
A and an annular portion 2B that absorbs the torsional vibration of the crankshaft 11. The fixing portion 2A is formed in a disk shape, and a hole 2C formed at the center is fitted into a protruding portion of the crankshaft 11 and is bolted to be fixed to the crankshaft 11. The annular portion 2B has a substantially quadrangular cross section and is orthogonal to the axis 8 orthogonal to the crankshaft 11.
It is a hollow member having a groove and is integrally formed on the outer periphery of the fixed portion 2A.

The inertia ring 3 is a solid ring-shaped member made of a material such as metal such as cast iron or steel and having a substantially quadrangular cross section, and is rotatably housed inside the annular portion 2B of the housing 2. . Therefore, the inertia ring 3 also has the axis orthogonal surface 8 orthogonal to the crankshaft 11.
The viscous fluid 4 is filled inside the annular portion 2B of the housing 2 to fill the gap between the inertia ring 3 and the housing 2. As the viscous fluid 4, conventionally used silicone oil, mercury, barium oxide, or the like can be used.

Here, the housing 2 and the inertia ring 3
The material, size, and the like are appropriately determined in consideration of the material of the viscous fluid 4, the diameter of the crankshaft 11, the rotational speed range, the acceleration range, and the like. Further, the clearance between the housing 2 and the inertia ring 3 is also appropriately determined so as to reduce the frictional resistance in consideration of such setting.

In such a viscous damper 1, a side surface slide body 5 as a slide body is provided on the inertial ring 3 side of the axis orthogonal surface 8. Further, an inner peripheral sliding body 6 as a sliding body is provided on the housing 2 side on an inner peripheral surface 9 formed by the inner diameter of the inertia ring 3 and a surface of the housing 2 corresponding to the inner diameter of the inertia ring 3. . The side slide body 5 is formed in a stepped columnar shape, that is, has a substantially T-shaped cross section. A plurality (8 in the present embodiment) of the side surface slide bodies 5 are provided on both axial orthogonal surfaces 8 of the inertia ring 3, and are arranged at equal intervals from the center of the inertia ring 3 in the circumferential direction. . One of the small diameter portions of the stepped columnar body forming the side surface slide body 5 is fitted into the fitting hole 3A formed in the axis orthogonal surface 8 on the inertia ring 3 side, so that the side surface slide body 5 becomes the inertia ring 3. It is fixed to. An amorphous carbon film 7 is formed on the end surface of the other large-diameter portion, and the amorphous carbon film 7 forms a sliding surface on the axis-orthogonal surface 8. The inner peripheral sliding member 6 is a thin plate-shaped member, and has an inner peripheral surface 9 on the housing 2 side.
It is fixed with adhesive or the like. An amorphous carbon film 7 is formed on the surface of the inner peripheral slide body 6, and the amorphous carbon film 7 constitutes the sliding surface of the inner peripheral surface 9.

Here, the side sliding member 5 and the inner peripheral sliding member 6
The material is polytetrafluoroethylene (PTFE, Poly Te
Tra Fluoro Ethylene), resin such as nylon, phosphor bronze, etc. can be adopted. In addition, the amorphous carbon film 7 (DLC film, Diam
The ond-like carbon film) is a thin film having an amorphous structure that has both a diamond structure and a graphite structure. Since the DLC film has an amorphous structure, it has excellent smoothness and a low friction coefficient, and also has a low opponent attacking property against a rubbing target. The DLC film is formed by
Plasma CVD (Chemical Vapo
(rDeposition, chemical vapor deposition) method, ionization vapor deposition method using benzene as a raw material, and arc ion plating method using graphite as a raw material. DLC
The hardness, adhesion, thickness, etc. of the film differ depending on the forming method and forming conditions.
It is appropriately selected in consideration of dimensions and the like.

In such a structure, when the engine 10 starts and the crankshaft 11 rotates due to the reciprocating motion of the piston, the flywheel 12 suppresses the uneven rotation of the crankshaft 11 due to the inertial force. On the other hand, in the viscous damper 1, the amorphous carbon film 7 on the axially orthogonal surface 8 and the inner peripheral surface 9 is viscous fluid 4 due to the inertial force of the inertial ring 3.
By sliding on the corresponding surfaces of the housing 2 and the inertial ring 3 via, the same operation as that of the flywheel 12 is performed, and these viscous damper 1 and flywheel 1
2 acts on both ends of the crankshaft 11 to absorb the torsion torque.

Further, if the rotational speed fluctuates during the operation of the engine 10, an inertial force is generated in the flywheel 12 by the positive or negative acceleration of the crankshaft 11, thereby suppressing a rapid change in the rotational speed. Also in this case,
In the viscous damper 1, the amorphous carbon film 7 on the axially orthogonal surface 8 and the inner peripheral surface 9 is viscous fluid 4 due to the inertial force of the inertial ring 3.
By sliding through, the torsion torque generated in the crankshaft 11 is absorbed by the same action as the flywheel 12.

In the embodiment having such a structure, the following effects can be obtained. (1) That is, since the amorphous carbon film 7 is provided on the axially orthogonal surface 8 and the inner peripheral surface 9 between the housing 2 and the inertia ring 3, even when the inertia ring 3 rotates inside the housing 2. Since the axis-perpendicular surface 8 slides by the amorphous carbon film 7 formed on the side surface sliding body 5, and the inner peripheral surface 9 slides by the amorphous carbon film 7 formed on the inner peripheral sliding body 6, the housing 2 The coefficient of friction between the inertia ring 3 and the inertia ring 3 can be minimized, wear of the viscous damper 1 can be reduced, and generation of wear powder can be suppressed. Therefore, heat generation due to friction during rotation can be reduced, and thermal deterioration of the viscous fluid 4 can be prevented,
The durability can be improved.

(2) Since a plurality of side surface sliding bodies 5 are provided on the axis orthogonal surface 8 of the inertia ring 3, and the circular sliding surfaces formed on these slide with the housing 2, the sliding surface is made small. Therefore, the friction of the axis orthogonal surface 8 can be reduced.
Further, since the amorphous carbon film 7 is formed on the side surface slide body 5, it is possible to reduce wear on the axis orthogonal surface 8. Although the crankshaft 11 is provided horizontally in the present embodiment, for example, when the crankshaft 11 is provided vertically, this axially orthogonal surface 8 is the most frictional surface due to gravity, which is particularly useful.

(3) Since the inner peripheral sliding member 6 having the amorphous carbon film 7 formed on the inner peripheral surface 9 on the housing 2 side is provided, the inner peripheral surface 9 is amorphous when the viscous damper 1 rotates. The high-quality carbon film 7 slides, whereby the coefficient of friction can be minimized, and thermal deterioration and wear of the viscous fluid 4 due to heat generation can be reduced. Therefore, durability can be improved. In particular, when the engine 10 is started, the crankshaft 11 is provided horizontally, so that the inertia ring 3
The inner peripheral surface 9 of the above contacts the inner peripheral surface 9 of the housing 2 due to gravity, and the frictional force of this portion increases, so that the effect of forming the amorphous carbon film 7 on this portion is remarkable.

(4) Since the side surface sliding member 5 and the inner peripheral sliding member 6 are composed of the inertia ring 3 and the housing 2 as separate members, at the time of manufacturing, the inertia carbon is formed after forming the amorphous carbon film 7 on them. The viscous damper 1 can be easily manufactured by assembling it in the ring 3 or the housing 2. Further, normally, when forming the amorphous carbon film 7, it is necessary to store the film-forming target in a container, but in the present invention, even if the housing 2 or the inertia ring 3 is not stored, it is formed smaller than these. Since the side surface slide body 5 and the inner peripheral slide body 6 which have been formed may be housed, the film can be easily formed.

It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within the scope of achieving the object of the present invention are included in the present invention. For example, although the inner peripheral sliding body 6 is provided on the housing 2 in the above-described embodiment, the inner peripheral sliding body 6 may be provided on the inner peripheral surface 9 of the inertia ring 3, or the housing 2 and the inertia ring 3 may be provided. May be provided in both. In short, it may be provided on at least one of the inner peripheral surface 9 of the inertia ring 3 and the inner peripheral surface 9 of the housing 2.

Further, the side slide body 5 is provided on the inertia ring 3, but the invention is not limited to this. The side slide body 5 may be provided on the housing 2, or the inertia ring 3 and the housing 2 may be provided.
And both may be provided. In short, it may be provided on at least one of the axis orthogonal surface 8 of the inertia ring 3 and the axis orthogonal surface 8 of the housing 2.

The sliding bodies were provided on both the axis-perpendicular surface 8 and the inner peripheral surface 9, but only the axis-perpendicular surface 8 or the inner peripheral surface 9 was provided.
May be provided only on the inertia ring 3
May be provided on at least one of the outer diameter and the surface of the inertia ring 3 inside the housing 2 corresponding to the outer diameter.
In short, the sliding body may be provided on at least a part of the inner surface of the housing 2 and the outer surface of the inertia ring 3.

The side slide body 5 had a T-shaped cross section, but as shown in FIG.
It may be fitted to A. Also, the number that can be installed,
Although the number is eight in the present embodiment, the number is not limited to this, and the number may be set so as to uniformly and stably slide on the axis orthogonal surface 8.

The amorphous carbon film 7 was formed on the end surface of the side surface sliding member 5 and the surface of the inner peripheral sliding member 6, that is, the sliding surface. However, the film is not limited to the sliding surface but the entire sliding member. It may be formed, and in short, it may be formed on at least the sliding surface. Further, the formation of the amorphous carbon film 7 is not limited to the side surface slide body 5 and the inner peripheral slide body 6, and, for example, directly on the inner surface of the annular portion 2B of the housing 2 or the outer surface of the inertia ring 3 without providing the slide body. You may form. In this case, the amorphous carbon film 7 may be provided on at least a part of at least one of the inner surface of the annular portion 2B of the housing 2 and the outer surface of the inertia ring 3.

The annular portion 2B and the inertia ring 3 of the housing 2 have a substantially rectangular cross section, but the shape is not limited to this, and other shapes such as an ellipse and a circle may be used.

The viscous damper 1 is a crankshaft 1
It was attached to the end of 1, but crankshaft 1
It may be provided in the middle of 1. In this case, for example, the flat plate-shaped fixing portion 2A is formed into a cylindrical shape matching the outer diameter of the crankshaft 11, the ring-shaped fixing portion is provided on the inner peripheral side of the annular portion, and the fixing portion is fixed to the crankshaft 11. Good. Further, the viscous damper 1 is used for the engine 10
However, the present invention is not limited to this and can be used for other rotary shafts such as an injection pump drive shaft that generates a torsion torque.

The best configuration, method and the like for carrying out the present invention have been disclosed above, but the present invention is not limited to this. That is, the invention is mainly illustrated and described with respect to particular embodiments, but without departing from the scope of the technical idea and object of the invention, the shape of the embodiments described above ,
Those skilled in the art can make various modifications in the material, quantity, and other detailed configurations. Therefore, the description limiting the shapes and materials disclosed above,
It is described as an example for facilitating the understanding of the present invention and does not limit the present invention.Therefore, the name of a member from which some or all of the limitations such as shape and material thereof are removed. The above description is included in the present invention.

[Brief description of drawings]

FIG. 1 is a side view showing a part of an engine according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a viscous damper according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a modified example of the sliding body of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Viscous damper, 2 ... Housing, 3 ... Inertial ring, 4 ... Viscous fluid, 5 ... Side sliding body which is a sliding body, 6 ...
Inner peripheral sliding body which is a sliding body, 7 ... Amorphous carbon film, 8 ... Axis orthogonal surface, 9 ... Inner peripheral surface, 11 ... Crank shaft which is a rotating shaft.

Claims (4)

[Claims] 1. An annular housing (2) attached to a rotating shaft (11), an inertia ring (3) rotatably provided inside the housing (2), and a filling inside the housing (2). Viscous fluid (4) and an amorphous carbon film (7) provided on at least a part of a sliding surface between the housing (2) and the inertia ring (3). Damper (1). 2. The viscous damper (1) according to claim 1, wherein the housing (2) and the inertia ring (3) are both formed in a substantially rectangular cross section, and are orthogonal to the rotation shaft (11). A viscous damper (1) having a surface (8) orthogonal to the axis, and at least one of the four surfaces of the inner surface of the housing (2) and the outer surface of the inertia ring (3) is a sliding surface. 3. The viscous damper (1) according to claim 2, wherein at least one of the housing (2) and the inertia ring (3) is provided with a sliding body (5) on the axis orthogonal surface (8). A sliding surface of the axis orthogonal surface (8) is formed by the sliding body (5), and an amorphous carbon film is formed on at least the sliding surface of the sliding body (5).
Viscous damper characterized in that (7) is provided
(1). 4. The viscous damper (1) according to claim 2 or 3, wherein the inertia ring (3) has an inner diameter (9) and the housing (2).
The inner surface (9) corresponding to the inner diameter (9) of the inertia ring (3)
And a strip-shaped sliding body (6) is provided on at least one of the inner side and the inner diameter (9) of the inertia ring (3) by the sliding body (6).
And the inner diameter of the inertia ring (3) on the inner surface of the housing (2)
A sliding surface with the surface (9) corresponding to (9) is formed, and an amorphous carbon film is formed on at least the sliding surface of the sliding body (6).
Viscous damper characterized in that (7) is provided
(1).