JPH0552220A - Clutch device - Google Patents

Abstract

PURPOSE:To eliminate generation of abnormal noises caused by oil shortage and improve durability by forming an Sn diffusion layer on surfaces of powder particles opposed to sintering holes of a sintered body which composes a bearing, and also forming sintering holes which have large diameters on portions surrounded by the Sn diffusion layer. CONSTITUTION:When a clutch is connected and disconnected, an end of a rotary shaft 3 goes in and out of a bearing 10 integrated with an end of a rotary shaft 1. In such a device, composition containing 14 to 40wt.%. of Sn, 0.5 to 4wt.% of C, remainder of Cu and inevitable impurity is provided. In a sintered body, powder particulates are fused to each other, while an Sn diffusion layer is formed on the surfaces of the powder particulates opposed to sintering holes of the sintered body. The bearing 10 is composed of such a device and a sintered oil-contained bearing wherein lubricating oil is impregrated into the sintering holes. The rotary shaft 3, going in and out of the bearing 10, are made of Fe alloy whose hardness is 40HRC or more and containing Cr. Abrasion of the rotary shafts 1, 3 is reduced, and durability is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch device, and more particularly, to a bearing excellent in lubricity and oil retention, and the wear of a rotating shaft which slides intermittently on this bearing and the generation of noise accompanying the sliding are small. The present invention relates to a clutch device.

[0002]

2. Description of the Related Art A drive shaft and a driven shaft are arranged so as to be freely connectable,
BACKGROUND ART A clutch device for intermittently transmitting power from a drive shaft side to a driven shaft side is used in a power system of automobiles and machine tools.

5 and 6 are cross-sectional views for explaining an example of use of a clutch device arranged to intermittently transmit power from an automobile engine to a rotary shaft on a transmission side. This clutch device includes a flywheel 2 formed integrally with a crankshaft 1 on the engine side.
A disc-shaped clutch disc 4 formed integrally with the transmission-side clutch shaft 3, and a driver 5
When the clutch pedal 6 is stepped on or released, the clutch disc 4 is released from the sliding surface of the flywheel 2 via the hydraulic circuit 7 and the diaphragm spring 8, or the pressure plate 9 is pressed against the sliding surface. Prepare In the center of the flywheel 2,
A pilot bush 10, which is a sintered oil-impregnated bearing that receives and slidably supports the end of the clutch shaft 3 that moves in the axial direction according to the gear shift, is press-fitted.

As shown in FIG. 5, when the clutch pedal 6 is depressed, the clutch disc 4 is pressed against the flywheel 2 by the clutch spring 8.
Is separated from the sliding surface, and the clutch shaft 3 is released from the rotational force of the engine. At this time, the end portion of the clutch shaft 3 is in a state of being disengaged from the pilot bush 10.

On the other hand, as shown in FIG.
When the clutch is released, the pressure plate 9 is biased toward the engine by the clutch spring 8, the clutch disc 4 is pressed against the flywheel 2, and the rotational force of the crankshaft 1 is transmitted to the clutch shaft 3 via the frictional force between the two. It In this way, when the clutch is connected, the end portion of the clutch shaft 3 on the left side in FIG. 6 is fitted into the pilot bush 10. At this time, a relative rotation speed difference between the crankshaft 1 and the clutch shaft 3 (maximum 7500 to 8000 rpm) is generated, so that the pilot bush 10 and the clutch shaft 3 are in sliding contact with each other at high speed. Further, when the clutch disc 4 comes into full contact with the sliding surface of the flywheel 2 without slipping, the rotation speeds of the pilot bush 10 and the clutch shaft 3 become the same, and both do not slide. As described above, the pilot bush 10 and the clutch shaft 3 slide intermittently with each clutch switching operation.
Since the lubricating oil impregnated inside exudes to the sliding surface, abrasion between both members is prevented. In order to prevent the lubricating oil from scattering on the sliding surface of the clutch device and losing the clutch function, the pilot bush as a bearing is formed as a sintered oil-impregnated bearing.

Conventionally, as a sintered oil-impregnated bearing of this type, Sn has been used.
8 to 11 wt%, C is 3% or less, and the remainder is formed by shaving cutting powder prepared by cutting out from an ingot having a composition substantially made of copper, and then impregnated with lubricating oil. In addition, bronze powder or copper (Cu) powder, tin (Sn) powder, lead (Pb) powder, or other metal powder, graphite (C)
A porous body (sintered body) obtained by mixing powder, compression molding, and sintering, and impregnating lubricating oil is used.

[0007]

However, in the clutch device using the pilot bush as the conventional oil-impregnated sintered bearing, the size of the sintered hole formed in the sintered body forming the pilot bush is small. The lubricating oil is poor in oil retention, especially when it is used as a bearing material that slides intermittently like a pilot bush.
There is a risk that oil will easily run out, abnormal noise such as gear noise will be generated when the clutch is switched, and the sliding portion will wear in a short period of time.

That is, in the case of a bearing material and a rotating shaft that are constantly sliding during operation, frictional heat is generated at the sliding interface immediately after the start of rotation, and the difference in expansion between the bearing metal and lubricating oil causes The lubricating oil gradually exudes to the sliding interface and an oil film can be formed.

On the other hand, in a so-called friction plate type clutch device in which the bearing and the rotating shaft slide intermittently at a high speed, there is a high possibility that oil will run out when the clutch is switched.

According to the knowledge of the present inventors, in order to solve the above-mentioned problems, the size of the sintered hole of the sintered body constituting the bearing is enlarged, and the lubricating oil is constantly applied to the surface of the sliding portion. It has been confirmed that it is necessary to form a sintered body, which is a bearing base material, so as to be in a floating state.

However, simply using a coarse raw material powder to increase the size of the sintering pores leads to a decrease in the sintering density, resulting in insufficient strength as a bearing that is susceptible to a mechanical impact force. Such a cylindrical bearing has a problem that the radial crushing strength is significantly reduced and the durability of the entire clutch device is also reduced.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to secure a large sintered hole without impairing the mechanical strength, which is excellent in oil retention and wear resistance. It is an object of the present invention to provide a clutch device having more excellent durability by mounting a sintered oil-impregnated bearing having high durability.

[0013]

In order to achieve the above-mentioned object, the present inventors produced sintered bearing bodies made of various material compositions by various methods, and compared and examined their characteristics. As a result, a sintered oil-impregnated bearing having high strength and a large sintering hole is obtained when the raw material powder to which a predetermined amount of coarse Sn raw material powder is added is fired, and as a result, the rotating shaft is less worn and is durable. The invention of the present application has been completed based on the knowledge that a clutch device having improved properties has been obtained.

That is, the clutch device according to the present invention is
By intermittently connecting a pair of rotary shafts arranged on a straight line, the transmission of power from one rotary shaft to the other rotary shaft is interrupted, and at the time of the intermittent operation, it is integrally provided at the end of one rotary shaft. In a clutch device in which the end of the other rotary shaft slidably comes in and out of the bearing, Sn has a composition of 15 to 40 wt%, C of 0.5 to 4 wt%, and the balance Cu and inevitable impurities. The powder particles are made of a sintered body which is fused to each other, and Sn is formed on the surface of the powder particles facing the sintering holes of the sintered body.
While forming the diffusion layer and forming the bearing by a sintered oil-impregnated bearing in which lubricating oil is impregnated in the sintered hole, the rotating shaft entering and leaving the bearing has a hardness of 40 H _RC or more and contains Cr. It is characterized in that it is formed of a Fe-based alloy.

Further, the above-mentioned Sn, C constituting the sintered body for bearings
It is also possible to further improve the lubricity and strength of the bearing by substituting at least one of Pb, Ni and metal sulfide for a part of copper (Cu) which is the rest of the components. In this case, the Pb content is suitably 0.5 to 3 wt%, and the Ni and metal sulfide contents are 1 to 10 respectively.
wt% is a suitable amount.

Further, the ratio of the sintered holes having an inner diameter of 40 μm or more is 5% with respect to all the sintered holes of the sintered body constituting the bearing.
By setting the above, lubricity can be improved.

The reasons for limiting the composition of the bearing used in the clutch device according to the present invention will be described below.

Sn is an element that alloys with copper, which is the main component of the bearing, to improve the sliding characteristics of the bearing, and in particular, coarse Sn powder with a particle size of 40 μm or more is used as a raw material powder for other purposes. By adding it to the raw material powder mixture, the pore size becomes 40
It is an element necessary for forming sintered pores of μm or more.
The content of Sn is 15 to 40 wt% with respect to the entire raw material powder
Is suitable, and in particular, in the method of manufacturing a sintered body for a bearing described later, in order to form a sintered hole having a large pore diameter, coarse Sn is used.
The powder content is set in the range of 5 to 30 wt%. If the content is less than 5 wt%, the formation ratio of the sintered pores having a large pore size is small, while if the content exceeds 30 wt%,
The proportion of pores increases, and the strength of the sintered body (radial crushing strength as a bearing) decreases.

C enhances the strength of the sintered body base of the bearing, and is dispersed as a solid lubricant in the base to enhance the lubricity of the sliding surface to prevent galling of the sliding material and to improve the initial sliding characteristics. In order to improve the content of 0.5 to 4 wt%. C content is 0.5
If it is less than wt%, the effect of improving the sliding characteristics is not sufficient, while if it exceeds 4 wt%, it becomes brittle and the formability decreases, and a high-density and high-strength sintered body is obtained. It is hard to be caught.

Cu is the main component that constitutes the sintered body base of the bearing, and 60 to 85 w is added to improve the strength of the sintered body.
Contains t%. If the content is less than 60 wt%, sufficient strength cannot be obtained, while if the content exceeds 85 wt%, the sliding characteristics deteriorate.

Pb has the effect of improving the lubrication characteristics of the bearing, and in addition to Sn and C mentioned above, Pb has a content of 0.
By containing 5 to 3 wt%, the lubricity of the sintered body can be further enhanced. If the content is less than 0.5 wt%, the effect of improving the lubricating property is small and the content is 3
If it exceeds wt%, the base strength will decrease.

Ni is an element effective for improving the strength of the sintered matrix of the bearing, and may be added by substituting a part of Cu in the range of 1 to 10 wt%. When the content is less than 1 wt%, the strength improving effect is not sufficient, while when the content exceeds 10 wt%, the expansion and coarsening of the sintered pores is hindered,
This reduces the lubricity of the bearing.

The metal sulfide is effective in improving the initial sliding characteristics of the bearing and is contained in the range of 1 to 10 wt%. If the content is less than 1 wt%, the improvement effect is not sufficient,
On the other hand, when the content exceeds 10 wt%, the bearing strength is lowered.

The sintered oil-impregnated bearing exhibiting the above-mentioned various characteristics is manufactured by the following steps. That is, first, copper powder or bronze powder prepared by the atomization method, 5 to 30 wt% Sn powder having an average particle size of 40 μm or more and graphite powder, Sn powder, Pb powder, Ni powder, metal sulfide, and solid for molding. A predetermined amount of a lubricant is added and mixed, and the composition excluding the solid lubricant is 15 to 40 wt% Sn and 0.5 C.
A raw material mixture having a composition of ˜4 wt%, the balance Cu and unavoidable impurities is prepared.

Next, this raw material mixture is molded at a molding pressure of 200-4.
Pressure molding at 00 MPa to form a molded body of a predetermined shape,
This molded body is heated to a temperature of 3 in a hydrogen or non-oxidizing atmosphere.
Degreasing is performed at 00 to 600 ° C. for 30 to 120 minutes, and then firing is performed in hydrogen or a non-oxidizing atmosphere at a temperature of 700 to 800 ° C. for 40 to 120 minutes to form a sintered body having sintered pores having a large pore size. ..

The manner in which sintered pores having a large pore size are formed will be described with reference to FIGS. 1 and 2. That is, as shown in FIG. 2, when the temperature of the compact is increased so as to fire the compact body in which the coarse Sn powder 2 is mixed between the powder particles 1, the Sn having a relatively low melting point is heated in the heating process below the sintering temperature. While the powder melts and adheres to the surface of the adjacent powder particles 1, a part of Sn diffuses from the surface of the powder particles 1 to the inside, and as shown in FIG. More Sn-rich Sn diffusion layer 3 is formed. As a result, coarse Sn
A sintered hole 4 having a large pore size is formed in the tissue space filled with the powder 2. Then, as a final step, a sintered oil-impregnated bearing is manufactured by impregnating the obtained sintered body with lubricating oil under reduced pressure.

Here, in the case of a sintered body which constitutes a bearing that slides intermittently, such as a pilot bush of an automobile clutch, the diameter of the sintered hole 4 is such that the lubricating oil always floats on the sliding surface. In order to maintain the state, it is desirable that the thickness be 40 μm or more. Further, it is desirable that the ratio of the sintered pores having a diameter of 40 μm or more to all the sintered pores is 5% or more.

The pore diameter of the sintered pores 4 and the generation ratio thereof can be adjusted by appropriately changing the average particle diameter of the Sn powder added together with the powder particles and the addition amount of the Sn powder. Specifically, in order to generate the sintered pores 4 having a pore size of 40 μm or more at a rate of 5% or more, coarse Sn powder having an average particle size of 40 μm or more is added in an amount of 5 wt% or more, and the temperature rises below the sintering temperature. In the warming process, it is necessary to melt the Sn powder.

The density of the sintered body is 6.8 to 7.3 g / cm.
The range of ³ is preferable, and in this range, the pore size is 40μ.
The ratio of the sintered pores of m or more to all the sintered pores is 5% or more, and a sintered body having excellent lubricity can be obtained, and the radial crushing strength is 100 N / mm ^{2 in} spite of expanding the sintered pores. The above bearing can be formed.

On the other hand, the rotary shaft that slides in and out of the sintered oil-impregnated bearing and slides intermittently is preferably a Fe-based alloy containing Cr and having an hardness of 40 H _RC or more. As an example of the alloy material, a general-purpose SCr material or SCM material is preferable. By adding a trace amount of Cr of about 1 wt% or less, the hardness of the rotary shaft can be increased to 40H _RC , and the wear resistance of the rotary shaft can be increased.

The rotary shaft formed of the above-mentioned material has excellent compatibility with the sintered oil-impregnated bearing having the above composition, and has a small amount of wear and galling, resulting in a combination having excellent sliding characteristics. Thus, the clutch device of the present invention is formed by combining the sintered oil-impregnated bearing having the above composition and the rotating shaft.

In the clutch device according to the present invention, the sintered pores of the sintered body forming the bearing can be set to be large without impairing the strength as compared with general sintered oil-impregnated bearing materials. A large amount of lubricating oil can be stored. Therefore, even at the moment when the sliding is intermittently started at the time of switching the clutch, the lubricating oil film exists at the sliding interface between the bearing and the rotating shaft, and the abnormal noise due to the oil shortage can be eliminated.

As described above, in the clutch device according to the present invention, the Sn diffusion layer is formed on the surface portion of the powder particles facing the sintering holes of the sintered body forming the bearing, and the Sn diffusion layer is surrounded by the Sn diffusion layer. Since a sintered hole having a large hole diameter is formed in the open portion, the lubricating oil retaining property is excellent, and a lubricating oil film is formed at the sliding interface even when the clutch is switched. as a result,
It is possible to provide a clutch device that does not generate abnormal noise due to oil shortage and that has less wear on the sliding portion and has excellent durability.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the clutch device according to the present invention will now be described in comparison with a conventional device by taking the case of application to the automobile clutch device shown in FIG. 5 as an example.

Sintered oil-impregnated bearings used in the clutch devices according to Examples 1 to 6 and Comparative Example 1 were prepared by the following procedure.

As Example 1, 88.5 wt% of bronze (Cu-10% Sn-1% Pb) powder having a particle size of 150 μm or less was used.
And 10 wt% of Sn powder having an average particle size of 40 μm and a particle size of 1
A mixed powder was prepared by adding 1.5 wt% of graphite powder having a particle size of 00 μm or less and 1 wt% of a solid lubricant for mold forming.

As Example 2, 88.5 wt% of bronze (Cu-10% Sn) powder having a particle size of 150 μm or less, 10 wt% of Sn powder having an average particle size of 40 μm, and 1.5 wt of graphite powder having a particle size of 100 μm or less. % And 1 wt% of a solid lubricant for mold forming were added to prepare a mixed powder.

As Example 3, 83 wt% of bronze (Cu-10% Sn) powder having a particle size of 150 μm or less and an average particle size of 4
0 wtm Sn powder 10 wt%, Ni powder 5 wt%,
A mixed powder was prepared by adding 1.5 wt% of graphite powder having a particle diameter of 100 μm or less and 1 wt% of a solid lubricant for mold forming.

As Example 4, 83.5 wt% of bronze (Cu-10% Sn) powder having a particle size of 150 μm or less, 10 wt% of Sn powder having an average particle size of 40 μm, 5 wt% of metal sulfide powder, and 100 μm of particle size. 1.5 wt% of the following graphite powder
% And 1 wt% of a solid lubricant for mold forming were added to prepare a mixed powder.

As Example 5, 83.5 wt% of bronze (Cu-10% Sn-1% Pb) powder having a particle size of 150 μm or less
And 10 wt% of Sn powder having an average particle size of 40 μm, 5 wt% of Ni powder, and 1.5% of graphite powder having a particle size of 100 μm or less.
1% by weight of a solid lubricant for mold forming was added to prepare a mixed powder.

As Example 6, 83.5 wt% of bronze (Cu-10% Sn) powder having a particle size of 150 μm or less, 10 wt% of Sn powder having an average particle size of 40 μm, 5 wt% of metal sulfide powder, and a particle size of 100 μm. 1.5 wt% of the following graphite powder
% And 1 wt% of a solid lubricant for mold forming were added to prepare a mixed powder.

On the other hand, as Comparative Example 1, 98.5 wt% of bronze (Cu-10% Sn-1% Pb) powder and 1.5 wt of graphite powder having a particle size of 100 μm or less were added without adding coarse Sn powder. %, And 1 wt% of a solid lubricant for mold forming were added to prepare a conventional mixed powder.

The mixed powders of Examples 1 to 6 and Comparative Example 1 thus prepared were pressed at a molding pressure of 200 to 400 MPa, and had dimensions of an outer diameter of 20 mm, an inner diameter of 16 mm and a height of 17 mm, and a molding density of 6 A molded product of 0.3 to 6.5 g / cm ³ was obtained. Then, each molded body is heated to a temperature of 30 in a hydrogen gas atmosphere.
Degreasing was performed by heating at 0 to 600 ° C. for 30 minutes to 2 hours.

Next, the degreased compacts were sintered in a depressurized hydrogen gas atmosphere at a temperature of 700 to 800 ° C. for 40 minutes to 2 hours and gradually cooled. Then, in the sizing step, as a result of adjusting the dimensional accuracy of the inner and outer diameters to a predetermined value, the density becomes 6.8.
A sintered body of ˜7.3 g / cm ³ was obtained. Then, the obtained sintered bodies were impregnated with lubricating oil under reduced pressure conditions to obtain sintered oil-impregnated bearings. The oil content of each bearing was 18 vol%.

In order to evaluate the lubricity and oil retention characteristics of each sintered oil-impregnated bearing thus prepared, a deoiling test under high temperature conditions was carried out in the following manner. The test conditions are
The bearing of each sample was placed in a furnace whose environmental temperature was set to 200 ° C., and the residual ratio of the lubricating oil retained in each bearing was measured with time at a predetermined time interval from the start of the experiment. The test results are shown in FIG.

As is clear from the results shown in FIG. 3, all the bearings according to Examples 1 to 6 are excellent in lubricity and oil retaining property, and when used as a pilot bush of a clutch device for automobiles, gear noise etc. It has been proved that the time until reaching the limit of the oil residual ratio (20 Vol%) for generating the abnormal noise is about 20% longer than that of the bearing according to Comparative Example 1, and the lubricating performance is significantly improved. It was

Further, in order to evaluate the wear resistance characteristics of the bearings used in the clutch devices according to Examples 1 to 6 and Comparative Example 1, each bearing was tested by using the Amsler type wear resistance tester shown in FIG. A peripheral speed of 23 m /
A wear resistance test was carried out by pressing the rotary drum 6 to which a load of 250 N was applied for 2 minutes for 2 hours and measuring the maximum wear depth of each test piece 5 as the wear amount.

Further, the metallographic structure of each sintered body was examined under a microscope to measure the ratio of the sintered pores having a pore diameter of 40 μm or more, and the radial crushing strength of each bearing was measured to obtain the results shown in Table 1 below. It was

[0049]

[Table 1]

As is clear from the results shown in Table 1, the sintered oil-impregnated bearings used in the clutch devices according to Examples 1 to 6 were compared with the conventional clutch device bearings shown in Comparative Example 1. Abrasion resistance is 2 without significantly reducing radial crushing strength
It was possible to improve it by about 0%. It should be noted that the bearings of Examples 3 and 5 in which the sintered body composition of the bearing contains Ni can have a radial crushing strength of 150 N / mm ² as compared with the other Examples 1, 2, 4, and 6. It was found that both the strength and the wear resistance can be improved, and the durability of the clutch device can be improved.

The sintered oil-impregnated bearings according to Examples 1 to 6 are mounted on the crankshaft side as the pilot bush 10 of the automobile clutch device shown in FIG. 5, while the crankshaft 3 entering and exiting the pilot bush 10 is SCr. An automobile equipped with a clutch device formed of steel (hardness 45H _RC ) was operated for a long time to investigate the performance of each clutch device, but no abnormal noise was generated during running.

In the above embodiments, the present invention is applied to the automobile clutch device. However, the application of the present invention is not limited to the automobile clutch device. For example, a clutch for a machine tool or a construction machine. The same can be applied to devices and the like.

[0053]

As described above, according to the clutch device of the present invention, the Sn diffusion layer is formed on the surface portion of the powder particles facing the sintering holes of the sintered body forming the bearing. Since a sintered hole having a large hole diameter can be formed in the portion surrounded by, a sintered oil-impregnated bearing having excellent lubricity and oil retention can be formed, and a bearing and a rotating shaft that slide intermittently can be formed. The lubricating oil film always exists at the sliding interface of. Therefore, it is possible to provide a clutch device that is excellent in durability without generating abnormal noise due to oil shortage.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a part of a matrix structure of a sintered oil-impregnated bearing used in a clutch device according to the present invention.

FIG. 2 is a cross-sectional view schematically showing a part of the matrix structure before sintering.

FIG. 3 is a graph showing changes over time in the oil residual rate of a sintered oil-impregnated bearing used in the clutch device according to each example, as compared with the conventional example.

FIG. 4 is a diagram showing a wear resistance test procedure of a bearing material.

FIG. 5 is a sectional view showing a state in which power is cut off in an automobile clutch device using a sintered oil-impregnated bearing.

FIG. 6 is a cross-sectional view showing a state in which power is transmitted in an automobile clutch device using a sintered oil-impregnated bearing.

[Explanation of symbols]

 1 powder particle 2 Sn powder 3 Sn diffusion layer 4 sintering hole 5 test piece 6 rotating drum

Claims (6)

[Claims] 1. A power transmission from one rotary shaft to the other rotary shaft is interrupted by connecting and disconnecting a pair of rotary shafts arranged on a straight line, and at the time of the interrupting operation, the end portion of one rotary shaft is interrupted. In a clutch device in which the end of the other rotary shaft is slidably inserted into and removed from a bearing integrally provided in the
A powder having a composition of 0 wt%, 0.5 to 4 wt% of C, the balance of Cu and unavoidable impurities, and composed of a sintered body in which powder particles are fused to each other and facing a sintering hole of the sintered body. While forming the Sn diffusion layer on the surface portion of the particle and forming the bearing by a sintered oil-impregnated bearing in which the lubricating oil is impregnated in the sintering hole, the rotary shaft entering and leaving the bearing has a hardness of 40H.
A clutch device characterized by being made of a Fe-based alloy containing at least _RC and containing Cr. 2. A power transmission from one rotating shaft to the other rotating shaft is interrupted by connecting and disconnecting a pair of rotating shafts arranged on a straight line, and at the time of the interrupting operation, one end of one rotating shaft is connected. In a clutch device in which the end of the other rotary shaft is slidably inserted into and removed from a bearing integrally provided in the
0 wt%, C 0.5-4 wt%, Pb 0.5-3 w
t%, the balance Cu, and unavoidable impurities, and the powder particles are composed of a sintered body fused to each other. An Sn diffusion layer is provided on the surface of the powder particles facing the sintering holes of the sintered body. The sintered oil-impregnated bearing, which is formed and impregnated with lubricating oil in the sintered hole, constitutes the above-mentioned bearing, while the rotary shaft entering and leaving the above-mentioned bearing has a hardness of 40 H _RC or more and a Fe system containing Cr. A clutch device formed of an alloy. 3. The transmission of power from one rotary shaft to the other rotary shaft is interrupted by disconnecting between a pair of rotary shafts arranged on a straight line, and an end portion of one rotary shaft during the interrupting operation. In a clutch device in which the end of the other rotary shaft is slidably inserted into and removed from a bearing integrally provided in the
0 wt%, C 0.5 to 4 wt%, Ni 1 to 10 wt%
%, Balance Cu and inevitable impurities,
The powder particles were made of a sintered body in which they were fused to each other, and a Sn diffusion layer was formed on the surface of the powder particles facing the sintering holes of the sintered body, and the lubricating oil was impregnated in the sintered holes. The sintered oil-impregnated bearing constitutes the above-mentioned bearing, while the rotary shaft entering and leaving the above-mentioned bearing has a hardness of 40 H _RC or more and Fe containing Cr.
A clutch device characterized by being formed of a system alloy. 4. The transmission of power from one rotary shaft to the other rotary shaft is interrupted by connecting and disconnecting a pair of rotary shafts arranged in a straight line, and at the time of the interrupting operation, one end of the rotary shaft is connected. In a clutch device in which the end of the other rotary shaft is slidably inserted into and removed from a bearing integrally provided in the
0 wt%, C 0.5-4 wt%, metal sulfide 1-1
The composition is 0 wt%, the balance is Cu, and unavoidable impurities, and the powder particles are made of a sintered body fused to each other. An Sn diffusion layer is provided on the surface of the powder particles facing the sintering holes of the sintered body. The sintered oil-impregnated bearing, which is formed and impregnated with lubricating oil in the sintered hole, constitutes the above-mentioned bearing, while the rotary shaft entering and leaving the above-mentioned bearing has a hardness of 40 H _RC or more and a Fe system containing Cr. A clutch device formed of an alloy. 5. The clutch device according to claim 1, wherein the ratio of the sintered holes having an inner diameter of 40 μm or more is 5% or more with respect to all the sintered holes of the sintered body forming the bearing. .. 6. The radial crushing strength of the sintered oil-impregnated bearing is 100 N / mm.
The clutch device according to claim 1, wherein the clutch device is set to ² or more.