JPH11206159A - Vibration type driving equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce wear of a hardened film of a vibrating body and obtain more stable motor performance, by forming a slide contact surface of one out of a vibrating body and a moving body of a composite resin layer in which resin or resin composition is filled with at least reinforcing material, and forming the other slide contact surface of a plating film having a recess. SOLUTION: A plating film is a nonelectrolytic plating film having porous surface quality. Its recess is coated with fluororesin (PTFE) as solid lubricant. Heat treatment is performed at a temperature higher than or equal to a melting point of PTFE, it is sealed and welded, the nonelectrolytic plating film is hardened, and a composite hardened film having self lubrication is obtained. An annular moving body 7 is concentrically fitted to the outer periphery of an intermediate member 15. The moving body 7 is constituted of an annular retainer 5 of aluminum alloy or the like and a composite resin layer 6 concentrically fixed on the surface of the retainer 5 with adhesive agent. As a result, wear due to friction drive of the slide contact surfaces of one composite hardened film and the other composite resin layer can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration type driving device, and more particularly to a vibration member which is a component of the vibration type driving device and a material of a sliding contact surface of a moving member which comes into pressure contact with the vibration member. It is.

[0002]

2. Description of the Related Art A vibration type driving device such as a vibration wave motor utilizes a friction between a vibrating body and a moving body which comes into pressure contact with the vibrating body to generate power in a form of converting vibrational energy into continuous mechanical kinetic energy. Source. Therefore, it is necessary that both sliding surfaces have self-lubricating properties and are made of a material having high wear resistance.

In a conventional vibration type driving device (hereinafter referred to as a vibration wave motor), a sliding surface of a moving body is made of polyether nitrile (trade name: Idemitsu PEN) which is a thermoplastic resin as a base resin, which is used as a reinforcing material. A composite resin layer filled with 10-20% by weight of PAN-based carbon fiber and further filled with fluororesin (PTFE) and graphite as a solid lubricant is used, and the sliding surface of the other vibrator has a particle diameter of 1 μm or less. 1.5 to 8.5% by weight of fluororesin (PTFE)
Co-folded electroless nickel plating film (Ni-p) with thickness 2
It was formed at 5 μm and cured by heating at 300 ° C. to form a self-lubricating cured film having a Vickers hardness (Hv) of 800 to 450.

The sliding surface of the moving body is formed of a heat-resistant and wear-resistant composite resin layer, and the sliding surface of the vibrating body is a self-lubricating cured film. This is because it was considered that the friction coefficient between the sliding contact surfaces was steadily stable, and that the abrasion of both sliding contact surfaces could be minimized.

[0005]

However, in the conventional vibration wave motor as described above, the rotational load is 5 kg.
cm and a rotation speed of 64 rpm, a continuous operation test was performed for 1800 hours. As a result, the wear amount of the composite resin layer on the sliding surface of the moving body was 18 μm, and the wear of the cured film on the sliding surface of the other vibrating body was circular. It was shown as circumferential wear marks, had a maximum depth of 2 μm, did not meet any of the wear requirements, and further reduction in wear was required.

An object of a first invention according to the present application is to further reduce wear of sliding surfaces of a moving body and a vibrating body in continuous operation of a vibration wave motor for a long period of time, and in particular, to harden the vibrating body. It is an object of the present invention to provide a vibration-type driving device having more stable motor performance by reducing abrasion of a film.

An object of a second invention according to the present application is to improve a self-lubricating hardened film which forms a sliding contact surface of a vibration wave motor in terms of surface properties, and to reduce a difference between a static friction coefficient and a dynamic friction coefficient. It is another object of the present invention to provide a vibration type driving device in which a stick slip at the time of starting is reduced.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a vibrating body in which vibration is excited, and a vibrating body in which a moving body is brought into contact with the vibrating body by a pressing force to perform a relative friction drive. In the mold driving device, one of the vibrating body and the moving body is formed of a composite resin layer in which at least a reinforcing material is filled in a resin or a resin composition, and the other sliding contact surface is a plating film having a recess. It is formed by.

Further, a solid lubricant (molybdenum disulfide, graphite, fluororesin, etc.) is provided in the recess of the plating film.
To form a composite cured film having self-lubricating properties.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) In a first embodiment of the present invention, an electroless plating film (Ni-p, Co-p, etc.) having a porous surface texture is used as the plating film. The recess is coated with a fluorocarbon resin (PTFE) as a solid lubricant, and is heated to a temperature equal to or higher than the melting point of PTFE (for example, 350 ° C.).
C), heat-sealing the PTFE, sealing and fusing the PTFE, and curing the electroless plating film to form a self-lubricating composite cured film.

As shown in FIG. 4, a conventional cured film of electroless plating obtained by co-folding PTFE has a particle size of 1 μm or less, for example, about 0.5 μm PTFE having a volume ratio of 5 μm in a plating film of 25 μm. It is uniformly dispersed by about 25%, so that the hardness or toughness for supporting the load is smaller than that of the cured film itself of electroless plating, which is disadvantageous in this point.

However, in the cured film of the electroless plating according to the first embodiment of the present invention, PTFE having a particle diameter of 1 μm or less is sealed only in the recesses dotted on the sliding contact surface, so that the load is not applied. The supporting hardness or toughness has the characteristics of the electroless plating itself, and has relatively high hardness and toughness, and a large amount of P.
It is a self-lubricating composite cured film in which TFE is encapsulated, and further improvement in wear resistance can be expected.

As a surface treatment technique for making an electroless plating film porous, there are Nidax (trade name: ULVAC TECHNO) or RESIST (trade name: Asahi Techno Produce). This is a well-known surface treatment technique for forming fine unevenness having a depth of 2 to 8 μm in a cured film in the process of forming a nickel plating film.

Next, as shown in FIG. 5A, PTFE having a particle size of 1 μm or less is coated on the concave portion of the electroless nickel film, and heat-treated at a temperature of about 350 ° C. higher than the melting point of PTFE. And PTFE are impregnated and fused to form a composite cured film having a strong self-lubricating property with strong adhesion.

As shown in FIG. 5 (b), another surface treatment technique employs a group 8 metal (Fe, Co, or Co) in the periodic table of Linden 809 and Combos P (both are trade names: World Metal Co., Ltd.). In the process of producing electroless plating by the catalytic action of Ni or the like, the cured film has a diameter and depth of 5 to 10 μm.
PTF coated with a takotsubo-shaped recess
In some cases, E is heat-treated at a temperature of 350 ° C. to form a composite cured film having self-lubricating properties.

(Second Embodiment) In a second embodiment of the present invention, as shown in FIG. 5C, the plating film has a crack (depth of 10 to 20 μm). This is chrome plating, in which PTFE is sealed in the microcrack-shaped recesses to form a self-lubricating composite cured film.

Examples of such techniques include Teff Rock (trade name: Otec) or Protonics System TA (trade name: Nippon Proton). The former employs porous chrome plating whose surface is a network-like crack. Heating at about 200 ° C., the bag-like crack is expanded, and PTFE fine particles that have been cooled and shrunk to −70 ° C. are enclosed therein and expanded to form a tightly adhered composite cured film. Is a method in which a composite material composed of PTFE and a heat-resistant resin binder is subjected to a special treatment to the same porous chrome plating, and ultrafine particles of PTFE are pressed and fixed.

The sliding surface of the vibrating body of the first and second embodiments has a high hardness and a moderate toughness for supporting a load,
This is a composite cured film having a surface property in which a wear-resistant plating film surface and a solid lubricant surface having non-adhesive and lubricity functions are separated.

Therefore, the hardness or toughness of the composite cured film of the present invention has the characteristics of the plating film itself, and supports the load, as compared with the cured film in which the conventional PTFE is uniformly dispersed on the entire sliding surface. This is advantageous in terms of abrasion resistance, and since PTFE, which is a solid lubricant, can be occupied in a large amount on the sliding surface, the frictional drive can be performed in the sliding direction in a short time.
Since the molecules are oriented to form the transfer film, the difference between the static and dynamic friction coefficients is small, and it is possible to reduce stick-slip during startup.

Further, since the transfer film of the solid lubricant can be formed in a short time, it is effective against the initial abrasion of any of the sliding surfaces of the composite cured film of the vibrating body and the composite resin layer of the moving body. is there.

[0021]

FIG. 1 shows an overall configuration of a vibration wave motor (vibration type driving apparatus) according to a first embodiment of the present invention, and FIG. 2 shows a configuration of the vibration wave motor. The vibrating body and the moving body that move are shown in an enlarged manner.

In these figures, reference numeral 1 denotes a thin ring-shaped piezoelectric element. Reference numeral 2 denotes a vibrating body made of an elastic material, and four protrusions (comb teeth) per [lambda] / 2 are formed on the sliding surface side of the vibrating body 2 at equal intervals over the entire circumference. A hardened film described later is formed on the surface (sliding contact surface) of each comb tooth. Further, the entire surface of the electrode surface of the piezoelectric element 1 is fixed to the surface of the vibrating body 2 opposite to the sliding contact surface, and the two constitute a stator.

Reference numeral 3 denotes a housing of the vibration wave motor, and a vibrating body 2 is concentrically fixed to the housing 3 by screws 4. The outer ring of the first ball bearing 11 is fixed to the center of the housing 3. Reference numeral 10 denotes a rotating shaft, and an intermediate member 15 is fixed to an axially intermediate portion of the rotating shaft 10 by, for example, shrink fitting. One end of the rotating shaft 10 is axially slidably supported by the inner ring of the first ball bearing 11, and the other end is axially slidably supported by the inner ring of the second ball bearing 12. The second ball bearing 1
The outer ring 2 is fixed to a central axis of a housing cover 8 fixed to the housing 3 with screws 9.

On the outer peripheral portion of the intermediate member 15, an annular moving body 7 is provided so as to fit concentrically. This moving body 7
Is composed of an annular support 5 made of an aluminum alloy or the like, and a later-described composite resin layer 6 concentrically fixed to the surface of the support 5 with an adhesive. An elastic sheet material 17 made of rubber is interposed between the back surface of the support 5 and the flange portion of the intermediate member 15, and a compression member provided between the intermediate member 15 and the inner ring of the second ball bearing 12. Spring member 1
The axial pressure generated by the pressure member 4 acts on the support 5 in the axial direction via the elastic sheet member 17.
By this axial pressure, the sliding contact surface of the moving body 7 (the surface of the composite resin layer 6) is pressed against the sliding contact surface of the vibrating body 2.

The axial pressing force generated by the compression spring member 14 (that is, the pressure contact force between the moving body 7 and the vibrating body 2) is
It can be adjusted by a spacer member (not shown) provided between the inner ring of the second ball bearing 12 and the compression spring member 14.

The composite resin layer 6 fixed to the support 5 is made of polyether nitrile (Idemitsu PEN: Idemitsu Material) which is a crystalline thermoplastic resin having a melting point of 340 ° C. and a glass transition point of 145 ° C. PAN-based carbon fiber as a reinforcing material in a weight ratio of 1%.
0%, and a fluororesin (PT
A composite resin layer filled with FE) and graphite was used.

Table 1 shows the configuration of the cured film, the Vickers hardness (Hv) and the friction coefficient μ of the vibrating body of the conventional vibration wave motor and the vibrating body 2 of the vibration wave motor of the present embodiment.

In the conventional example, a fluorine resin (PTFE) is co-folded by about 7.5% by weight on an electroless nickel film (Ni-p).
Heat treatment was performed at 300 ° C. to obtain a predetermined Vickers hardness and a friction coefficient.

In this embodiment, an electroless nickel plating film having a porous surface property is adopted, PTFE having a particle size of 1 μm or less is coated on the concave portion of the cured film for forming fine irregularities, and a temperature of 360 ° C. The composite cured film heat-treated in was used.

[0030]

[Table 1]

Table 2 shows the target performance of the vibration wave motor of this embodiment, and Table 3 shows the main design specifications.

[0032]

[Table 2]

[0033]

[Table 3]

A vibration wave motor having the structure shown in FIG. 1 in which the vibration body 2 of the present embodiment was incorporated into the vibration wave motor having the above-described design specifications was manufactured, and a continuous operation test was performed in accordance with the target performance shown in Table 2.

In the test, a perm torque (trade name: manufactured by Kojin Seisakusho) was communicated to the output side of the rotating shaft 10 of the motor, the rotating load was set to 5 kgcm, the rotating plate of the encoder was supported at the other end of the rotating shaft, and 64 rpm. It was controlled at a constant level.

The performance of the motor was measured at 300 hour intervals,
The wear of the sliding contact surface was measured at 900-hour intervals, giving a total of 18
A continuous rotation test of 00 hours was performed.

The motor performance is greatest in the early stage of operation, and tends to decrease slightly as time progresses, but the fluctuation range is smaller than that of the conventional vibrating body motor.

The reason is that the transfer film of PTFE on the sliding surfaces of the vibrating body and the moving body is formed in a shorter time in the present embodiment than in the conventional example, and the variation of the wear coefficient of the sliding surface is changed. This is probably due to the small width.

Since the lubricating PTFE of this embodiment occupies a large amount on the sliding contact surface, the transfer film in the sliding direction is generated quickly, the difference between the static and dynamic friction coefficients is small, and the startability is excellent. It was also confirmed that.

The wear amount of the composite resin layer on the sliding contact surface of the moving body by continuous operation was 6 μm after 900 hours, 10 μm after 1800 hours, the wear rate per hour was 0.006 μm, and the conventional wear rate was 0.01 μm. It was smaller.

Further, the maximum depth of the friction mark of the composite cured film of the vibrating body was improved to 0.9 μm.

(Second Embodiment) FIG. 3 is an enlarged view of a vibrating body and a moving body of a vibration wave motor according to a second embodiment of the present invention.

In FIG. 3, reference numeral 51 denotes a piezoelectric element, and 52, a vibrator to which the piezoelectric element 51 is fixed, which is made of the same material and shape as the vibrator of the vibration wave motor of the first embodiment.

Reference numeral 56 denotes a composite resin layer, which is fixed to the surface of the comb teeth of the vibrator with an adhesive, and is the same material as the composite resin layer fixed to the support of the first embodiment.

Reference numeral 57 denotes a moving body made of an aluminum alloy having the same shape and dimensions as the support 5 of the first embodiment, and the surface thereof (the surface in sliding contact with the composite resin layer 56) has the first shape. This is a composite cured film obtained by impregnating and welding fluorine resin (PTFE) in a recess of an electroless nickel film having the same kind of porous surface properties as the vibrating body cured film of the example.

[0046]

As described above, according to the present invention,
A plating film having a recess is formed on one of the sliding surfaces of the vibrating body and the moving body, and the recess is filled with a solid lubricant, for example, fluororesin (PTFE). The self-lubricating composite cured film is formed by separating the wear-resistant plating film surface and the lubricating solid lubricant surface, so the plating film itself has high wear resistance and the solid lubricant lubrication function. By the synergistic effect of the above, it is possible to reduce the abrasion in the friction drive of the respective sliding contact surfaces of the one composite cured film and the other composite resin layer.

Further, since a solid lubricant such as a fluororesin (PTFE) enables a transfer film to be formed between the sliding surfaces in a short time, the difference between the static and dynamic friction coefficients is small, and Can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a vibration wave motor according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of a vibrating body and a moving body of FIG. 1;

FIG. 3 is a partially enlarged sectional view of a vibrating body and a moving body according to a second embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a conventional cured film.

FIGS. 5A and 5B are enlarged sectional views of the composite cured film of the first embodiment, and FIGS. 5C and 5C are enlarged sectional views of the composite cured film of the second embodiment.

[Explanation of symbols]

 1, 51: piezoelectric element 2, 52: vibrator 5: support 6, 56: composite resin layer 7, 57: moving body

Claims (6)

[Claims] 1. A vibration-type driving device that relatively frictionally drives a vibrating body for which vibration is excited and a moving body that presses and contacts the vibrating body, wherein one of the vibrating body and the moving body is slidably contacted. A vibration type driving device, wherein the surface is formed of a composite resin layer in which a resin or a resin composition is filled with at least a reinforcing material, and the other sliding contact surface is formed of a plating film having a recess. 2. The vibration-type driving device according to claim 1, wherein a solid lubricant is sealed in the recess of the plating film to form a composite cured film having self-lubricating properties. 3. The vibration type driving device according to claim 1, wherein the solid lubricant is a fluororesin. 4. The vibration type driving device according to claim 1, wherein said plating film is an electroless plating film having a porous surface property. 5. The method according to claim 1, wherein the recess of the electroless plating film is coated with a fluororesin as a solid lubricant, and heat-treated at a temperature equal to or higher than the melting point to fuse the fluororesin and to cure the electroless plating film. The vibration type driving device according to claim 1, 2, 3, or 4, wherein 6. The plating film according to claim 1, wherein said plating film is chrome plating having cracks.
The vibration-type driving device according to item 1.