JP2003348862A - Vibration wave motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve durability of a contact section of a vibration element with a relative moving member at a low cost and to enable a stick slip to be reduced at starting. <P>SOLUTION: A vibration wave motor comprises a vibrator 11 having a piezoelectric element 13 vibrated by a drive signal, and an elastic section 12 connected to the element 13 for generating an vibration wave on a drive surface made of a metal by its vibration; a moving element 17 having a sliding surface 17a made of a metal brought into pressure contact with the drive surface 12c of the section 12 to generate a relative motion by the vibrating wave; and a sliding material supply section 30 brought into contact with the sliding surface 17a of the element 17, to supply a sliding material for holding the suitable sliding state on the sliding surface 17a by the sliding operation. The supply section 30 has a sliding member 32 disposed in the groove 12a of the section 12 to include the sliding material such as PTFE or the like, and an elastic member 31 mounted with the member 32 to bring into pressure contact with the sliding surface 17a of the element 17 by its elasticity. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration wave motor having an improved structure of a contact portion between a vibrator and a moving element.

[0002]

2. Description of the Related Art Conventionally, a vibration wave motor of this type generates a progressive vibration wave on a driving surface of an elastic body by utilizing expansion and contraction of a piezoelectric body, as is known in Japanese Patent Publication No. 1-17354. Due to this traveling wave, an elliptical motion is generated on the driving surface, and the moving element that comes into pressure contact with the wave front of the elliptical motion is driven. Such a vibration wave motor has a feature that it has a high torque even at a low rotation, so that when mounted on a driving device, the gear of the driving device can be omitted, thereby eliminating gear noise and positioning accuracy. There is an advantage that can be improved.

FIG. 7 is a diagram showing the driving characteristics of a vibration wave motor by comparing the frequency-rotation speed characteristics when a metal and a sliding member are attached to each other. Assuming that the static friction coefficient is μs and the dynamic friction coefficient is μd, as shown in FIG. 7A, when the contact portion between the vibrator and the mover is made of metal, there is a relation of μs> μd. In this case, the characteristics of the frequency f and the rotational speed N are as shown by a curve A2 from the upper side to the lower side when the vibration wave motor decelerates from a high speed. There is a portion A1-1 where the rotation does not rise up to a certain number of rotations as indicated by a curve A1.

As shown in FIG. 7B, when a sliding member such as PTFE is adhered, there is a relation of μs ≒ μd.
The case where the rotation speed is increased (curve B1) and the case where the rotation speed is decreased (curve B2) are substantially the same, and there is no place where the rotation speed suddenly decreases and stops. For this reason, many conventional vibration wave ultrasonic motors have a sliding material such as PTFE adhered thereto. However, when sticking a sliding material, the manufacturing cost is high, and when metal is used, the contact part is more faithful to the basic design, there is no loss in driving force, and performance is lower than when sticking a sliding material. Good.

FIG. 8 is a diagram schematically showing a contact portion between a vibrator and a moving element of a conventional vibration wave motor. FIG. 8 (a)
As shown in (2), when the contact portion between the vibrator 81 and the mover 82 is made of metal, only the wave front of the vibration wave generated in the vibrator 81 hits and the mover 82 advances. However, FIG.
As shown in (b), when the sliding member 83 is stuck, the sliding member 83 seems to be indented, and the speed distribution of the contact surface has a loss at a place other than the peak, and the transmission is performed. There was a problem of inefficiency.

FIG. 9 is a diagram showing the drive characteristics of a conventional vibration wave motor when the contact portion between the vibrator and the mover is made of metal and when a sliding material is adhered, corresponding to the amplitude. When the amplitude of the vibrator is small (see FIG. 9B), FIG.
As shown in FIG.
In the case of B, as described above, if the sliding material 83 is sunk and the amplitude does not become large to some extent,
The same vibrator 81 does not move at low speed when the sliding member 83 is attached.

To solve such a problem, Japanese Patent Laid-Open No. 7-264881 discloses a contact portion between a vibrator and a moving element.
Discloses an aluminum hard oxide film impregnated with PTFE (polytetrafluoroethylene).
Japanese Patent Application Laid-Open No. 11-206159 discloses that a large number of concave portions are provided in a plating film and PTFE is melted and embedded in the concave portions.

[0008]

SUMMARY OF THE INVENTION Japanese Patent Application Laid-Open No. H11-2061
No. 59 discloses a method in which a large number of concave portions are provided in a plating film and PTFE is melted and embedded in the concave portions. However, in addition to increasing the cost for providing a large number of concave portions in the plating film, similar to the case described above, Since the PTFE is embedded in the surface, the layer in which the PTFE is embedded may be lost while the ultrasonic motor is being driven, and there is a problem that the durability is poor.

On the other hand, Japanese Patent Application Laid-Open No. Hei 7-264881 discloses a method in which a hard oxide film of aluminum is impregnated with PTFE (polytetrafluoroethylene), specifically, a hole of 1 μm or less formed on the surface of the hard oxide film is impregnated with PTFE. However, PTFE may not be deeply impregnated in some cases, and the layer impregnated with PTFE may be lost while the vibration wave motor is being driven. there were.

[0010] An object of the present invention is to maintain a low cost without attaching a sliding material and to provide a vibrating body (vibrator) and a relative motion member (moving element) while maintaining a contact portion between metals having good driving performance. The object of the present invention is to provide a highly reliable vibration wave motor capable of improving the durability of the contact portion and improving the rising characteristics of the rotation at the time of starting.

[0011]

According to a first aspect of the present invention, there is provided a piezoelectric member which is excited by a drive signal and which is joined to the piezoelectric member. A vibrating body having an elastic body that generates a vibrating wave;
A relative motion member having a sliding surface made of metal that is brought into pressure contact with the drive surface of the elastic body and generating relative motion by the vibration wave; And / or the sliding surface of the relative motion member extends from the inside of the vibrating body and / or the pressing direction of the relative motion member, and the sliding surface and / or the sliding motion by the relative motion. A vibration wave motor having a sliding material replenishing section for replenishing a sliding material on a driving surface.

According to a second aspect of the present invention, in the vibration wave motor according to the first aspect, the elastic body has a groove on a driving surface, and the sliding material supply section is disposed in the groove. The vibration wave motor is characterized in that:

[0013] The invention of claim 3 is claim 1 or claim 2.
5. The vibration wave motor according to claim 1, wherein the sliding material replenishing portion is provided with a sliding member containing the sliding material and the sliding member, and the elastic member is used to move the sliding member to the relative motion member. And a biasing member for bringing the sliding surface into pressure contact with the sliding surface of the vibration wave motor. According to a fourth aspect of the present invention, in the vibration wave motor according to any one of the first to third aspects, the sliding member is made of PTFE (polytetrafluoroethylene), and the urging member is made of PTFE (polytetrafluoroethylene). Is a vibration wave motor characterized by being made of silicone rubber.

[0014] The invention of claim 5 is the invention of claim 1 or claim 2.
The vibration wave motor according to the above, wherein the vibration body is supported,
And a support portion for supporting the relative movement member in a state capable of relative movement, wherein the sliding material replenishing portion is provided with a sliding member containing the sliding material, and the sliding member is mounted, A vibrating wave motor having a base fixed to the support portion, and an urging member for pressing the sliding member against the sliding surface of the relative motion member by elasticity.

According to a sixth aspect of the present invention, in the vibration wave motor according to the first aspect, the elastic body is an annular member having a comb-shaped groove on a driving surface that is substantially perpendicular to the driving direction. The vibration material motor is characterized in that a plurality of the sliding material supply units are arranged in the groove. Claim 7
According to the invention, in the vibration wave motor according to claim 6, the sliding material replenishing portions are respectively arranged within a range that divides a circumference of the annular member at equal intervals. Vibration wave motor. According to an eighth aspect of the present invention, in the vibration wave motor according to the seventh aspect, the sliding material replenishing portion is disposed substantially at the center in the range.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a vibration wave motor according to the present invention will be described in detail with reference to the accompanying drawings. In the following embodiments, an ultrasonic motor using an ultrasonic vibration region will be described as an example of a vibration wave motor. (First Embodiment) FIG. 1 is a diagram illustrating an ultrasonic motor 10 according to a first embodiment of the present invention. FIG. 2 is an external perspective view showing the vibrator 11 and the moving element 17 of the ultrasonic motor 10 according to the first embodiment.

The ultrasonic motor 10 according to the first embodiment includes a vibrator 11 and a moving element 17, in which the vibrator 11 side is fixed and the moving element (relative moving member) 17 is driven to rotate. I have. The vibration absorbing member 14, the pressing plate 15, and the pressing member 16 are arranged below the vibrator 11, and the vibration absorbing member 18 and the output transmitting member 19 are arranged above the moving element 17. .

The vibrator 11 includes an elastic body 12 and an elastic body 12.
And an electromechanical conversion element (hereinafter, referred to as a piezoelectric body) 13 such as a piezoelectric element or an electrostrictive element for converting electric energy into mechanical energy, which will be described later. A traveling wave is generated in the vibrating body 11. In the present embodiment, as an example, a description will be given of nine traveling waves.

The elastic body 12 is made of a metal material having a large resonance sharpness, and has an annular shape. The elastic body 12 has a groove 12a cut on the opposite surface to which the piezoelectric body 13 is joined, and a protrusion (a portion without the groove 12a) 1
The tip surface of 2b becomes the drive surface 12c and is brought into pressure contact with the moving element 17. The reason for cutting the groove 12a is to make the neutral plane of the traveling wave as close to the piezoelectric body 13 as possible, thereby amplifying the amplitude of the traveling wave on the driving surface 12c.

The piezoelectric body 13 is divided into two phases (A phase and B phase) along the circumferential direction.
Elements with alternate polarizations are arranged every two wavelengths,
An interval of 1/4 wavelength is provided between the A phase and the B phase.

Below the piezoelectric body 13, a vibration absorbing member 14,
The pressing plate 15 and the pressing member 16 are arranged. The vibration absorbing member 14 is disposed below the piezoelectric body 13 and is a member for preventing the vibration of the vibrator 11 from being transmitted to the pressing plate 15 and the pressing member 16. For example, a nonwoven fabric, felt, or the like is used. Have been. The pressing plate 15 is a member that transmits a pressing force for receiving the pressing of the pressing member 16. The pressing member 16 is disposed below the pressing plate 15 and is a member that generates a pressing force. In the present embodiment, the pressing member 1
Although 6 is a disc spring, a coil spring or a wave spring may be used instead of the disc spring.

The moving element 17 is made of a light metal such as aluminum, and the surface of the sliding surface 17a is subjected to a surface treatment for improving abrasion resistance. On top of this mover 17,
In order to absorb the vibration of the moving element 17 in the pressing direction, a vibration absorbing member 18 such as rubber is arranged, and an output transmitting member 19 is arranged thereon.

The ultrasonic motor 10 is incorporated in a vibration motor unit 100. The vibration motor unit 100 includes a cylindrical support member 101 and a support member 10.
Pressing ring 1 attached to the outside lower end of 1 by screw
2 and the outer periphery of the support member 101 (three equally spaced parts, FIG.
(Only one is shown in the figure), and a protrusion 10 that engages with the groove of the elastic body 12 and regulates the rotation direction of the vibrator 11.
3, a bearing 104 provided at the upper end of the outer periphery of the support member 101, and a movable member 17 provided in the bearing 104, which regulates the pressing direction and the radial direction of the output transmission member 19, thereby moving the movable element 17 in the rotational direction. A regulating member 105 that is movable and regulates the pressing direction and the radial direction is provided.

The vibration motor unit 100 can be configured as a single unit incorporating the ultrasonic motor 10 including the output transmission member 19 by the structure described above. The output transmission member 19 is provided with a projection (not shown), and the rotation of the ultrasonic motor 10 is output from the projection to the outside of the vibration motor unit 100.

FIG. 3 is a block diagram for explaining the drive control device 20 for the ultrasonic motor according to the first embodiment. First, the configuration of the drive control device 20 for the ultrasonic motor will be described. The drive control device 20 includes an oscillation unit 21 and a control unit 2
2, a phase shift unit 23, amplification units 24 and 25, and a detection unit 26
And the like.

The oscillating unit 21 receives a command from the control unit 22
A drive signal of a desired frequency is generated. The phase shift unit 23 divides the drive signal generated by the oscillator 21 into two drive signals having different phases by 90 °. The amplifying units 24 and 25 include a phase shift unit 23
The two drive signals divided by are boosted to desired voltages, respectively. The drive signals from the amplifiers 24 and 25 are
The traveling wave is transmitted to the ultrasonic motor 10, and the traveling signal is generated in the vibrator 11 by the application of the driving signal, and the moving element 17 is driven. The detection unit 26 is configured by an optical linear encoder or the like, and detects the position and speed of a driven body (not shown) driven by driving the moving element 17.

The control unit 22 controls the driving of the ultrasonic motor 10 based on a driving command from the CPU. And
The control unit 22 receives the detection signal from the detection unit 26, obtains position information and speed information based on the values, and controls the frequency of the oscillator 21 so as to be positioned at the target position.

Next, the operation of the ultrasonic motor drive control device 20 of this embodiment will be described. First, the target position is transmitted to the control unit 22. A driving signal is generated from the oscillating unit 21, and the driving signal is divided by the phase shift unit 23 into two driving signals having phases different from each other by 90 °.
It is amplified to the desired voltage. The drive signal is the ultrasonic motor 1
0 is applied to the piezoelectric body 13, and the piezoelectric body 13 is excited,
Due to the excitation, a ninth-order bending vibration is generated in the elastic body 12. The piezoelectric body 13 is divided into an A phase and a B phase, and a drive signal is applied to the A phase and the B phase, respectively. A
The ninth bending vibration generated from the phase and the ninth bending vibration generated from the B phase are such that the positional phase is shifted by ４ wavelength, and the A-phase drive signal and the B-phase drive signal are different from each other. , 9
Since the phases are shifted by 0 °, the two bending vibrations are combined to form nine traveling waves.

The traveling wave has an elliptical motion at its wave front. Therefore, since the moving element 17 is in pressure contact with the driving surface 12c, it is frictionally driven by this elliptical motion. The detection unit 26 is disposed on a driven body driven by driving the moving element 17, and a signal of an electric pulse generated from the detection unit 26 is transmitted to the control unit 22. Control unit 22
Can obtain the current position and the current speed based on this signal, and control the drive frequency of the oscillation unit 21 based on the position information, the speed information, and the target position information.

FIG. 4 is a view for explaining a sliding material supply section of the ultrasonic motor according to the first embodiment. The sliding material replenishing section 30 of the first embodiment extends from the inner side in the pressing direction of the elastic body 12 to the driving surface of the elastic body 12 and slides on the sliding surface of the moving element 17 by a sliding operation by relative motion. An elastic member 31 made of a silicone rubber block, which is provided in one of the grooves 12a of the elastic body 12, and
The sliding member 32 made of a TFE (polytetrafluoroethylene) block is overlapped with the sliding member 32 so that the sliding member 32 comes into contact with the sliding surface 17 a of the moving element 17.

Next, a specific structure of the ultrasonic motor according to the first embodiment will be described. The elastic body 12 is made of stainless steel (S
US17), and the moving element 17 is manufactured by subjecting aluminum to hard anodizing. The elastic member 31 is a silicone rubber block having a rectangular parallelepiped shape, and has a soft hardness of about Hs = 30. The sliding member 32 is an L-shaped PTFE block for attaching to the head of the elastic member 31.
00% PTFE (trade name: Nichias Corporation, Naflon P)
TFE etc.).

An elastic member 31 is provided in the groove 12a of the elastic body 12.
And the sliding member 32 is placed thereon as shown in FIG. At this time, the height h when the elastic member 31 and the sliding member 32 overlap is set to be larger than the groove depth d of the elastic body 12. By doing so, when the moving element 17 is pressed against the elastic body 12 by the pressing force, the elastic member 31 is compressed, and the elastic force thereof causes
The PTFE of the sliding member 32 is always in contact with the sliding surface 17a of the moving element 17, so that the PTFE material as the sliding material can always be supplied. It is preferable that the height h when the elastic member 31 and the sliding member 32 overlap each other is about 0.05 to 0.3 mm larger than the groove depth d of the elastic body 12.

An elastic member incorporating the elastic member 31 and the sliding member 32 so that the elastic member 31 and the sliding member 32 do not come off while the ultrasonic motor 10 is being driven. It is desirable that the outer peripheral surface of the groove 12a is closed with a fixing member such as a tape. In addition, since the elastic member 12 has the support member 101 on the inner peripheral side, the elastic member 12 does not come off on the inner peripheral side.

As described above, according to the first embodiment, the elastic member 31 made of silicon rubber and the sliding member 32 made of PTFE are overlapped, and the elasticity of the elastic member 31 causes the sliding member 32 to overlap. Since the PTFE material is brought into contact with the sliding surface 17a of the moving element 17, the PTFE material is always supplied. For this reason, even if the ultrasonic motor 10 is driven for a long time, the effect of the sliding performance by the PTFE material is always obtained, and the durability can be improved. Further, it is no longer necessary to perform a special surface treatment such as providing an extremely fine concave portion on the sliding surface 17a of the movable element 17 and the driving surface 12c of the elastic body 12, and dissolving and filling the concave portion with a PTFE material.

(Second Embodiment) FIG. 5 is a view for explaining a sliding material supply section of an ultrasonic motor according to a second embodiment. In the following embodiments, portions that perform the same functions as those in the first embodiment described above are denoted by the same reference numerals or the same reference numerals at the end, and overlapping drawings and descriptions will be omitted as appropriate. In the sliding material supply section 30 of the first embodiment,
An elastic member 31 made of a silicone rubber block and a sliding member 32 made of a PTFE block are superimposed on the groove 12a of the elastic body 12 so that the sliding member 32 contacts the sliding surface 17a of the moving element 17. However, there are two members,
The assemblability was not always good. For this reason, the sliding material supply unit 40 of the second embodiment is formed by bonding a sliding member 42 made of a PTFE sheet to a head of an elastic member 41 made of a silicone rubber block.

The elastic member 41 is made of a silicone rubber block and has a shape as shown in FIG.
The hardness was set to about soft. In addition, the sliding member 42
It is manufactured from a PTFE sheet of 00% PTFE (trade name: Nippon Valqua Industry Co., Ltd., VALFLON sheet 7000, etc.).

The sliding member 42 was made to roughen the surface roughness of one side of the PTFE sheet, applied with an elastic adhesive, and adhered to the silicon rubber block elastic member 41 using a mold. By doing so, it is possible to easily integrate the elastic member 41 of the silicone rubber block with the sliding member 42 of the PTFE sheet.

In the second embodiment, the sliding material supply section 40
The height h of the silicon rubber block with the TFE sheet is also the same as in the first embodiment, and is greater than the groove depth d of the elastic body 12.
It is preferable that the elastic member 41 made of a silicone rubber block is compressed when the movable member 17 is pressed against the elastic body 12 by a pressing force, and the elastic member 41 has a large elasticity. By force, the PTFE of the sliding member 42
The material can always contact the sliding surface 17a of the moving element 17.

According to the second embodiment, in addition to the effects of the first embodiment, there is an effect that the assemblability is improved.

(Third Embodiment) FIG. 6 is a view for explaining a sliding material supply section of an ultrasonic motor according to a third embodiment. The sliding material replenishing portion 50 of the third embodiment has a thin plate-shaped leaf spring member 51 having a base portion screwed to the holding ring 102, an upper portion bent inward, and having a thinly formed mounting portion, and A sliding member 52 made of a PTFE block or a PTFE sheet attached to an attachment portion of the leaf spring member 51, and a portion of the sliding member 52 to which a PTFE material is attached by utilizing the spring property of the leaf spring member 51. Contact the sliding surface 17a of the moving element 17.

The leaf spring member 51 is made of phosphor bronze, brass, SU
It is an L-shaped thin plate such as an S material, and a mounting portion for mounting the sliding member 52 made of PTFE material is thinner than the groove width of the elastic body 17. The leaf spring member 51 has a hole on the opposite end side (base side) of the thin portion of the thin plate so that the leaf spring member 51 can be screwed to the holding ring 102 of the support member 101. 100% P with sliding member 52
It is produced from a PTFE sheet of TFE.

In the third embodiment, the sliding material replenishing section 50 is in the form of a thin plate with a PTFE sheet, and when the moving element 17 is not pressed against the vibrator 11, the sliding material PTFE is used. The leaf spring member 51 is also urged by the moving member 17 when the moving member 17 is pressed against the vibrator 11. By doing so, the spring property of the leaf spring member 51 allows the PTFE material of the sliding member 52 to always contact the sliding surface 17a of the moving element 17.

(Fourth Embodiment) FIGS. 10 to 12 show a fourth embodiment.
FIG. 1 is a schematic diagram for explaining an ultrasonic motor 10 according to an embodiment. The traveling wave motor 10 according to the fourth embodiment includes the vibrator 1
The first elastic body 12 is an annular member having a comb-shaped groove portion 12a on the driving surface that is substantially perpendicular to the driving direction (see FIG. 2).
The plurality of sliding material supply units 60 are arranged in the comb-shaped groove 12a. The sliding material replenishing portions 60 are respectively arranged within ranges where the circumference of the annular member is equally spaced. At this time, it is preferable that the sliding material replenishing portion is disposed substantially at the center of the range.

The ring-shaped ultrasonic motor 10 usually has 36
Although rotation by 0 degrees is possible, it is not necessarily used by rotating by 360 degrees. As shown in FIG. 10A, only one sliding material replenishing section 60 is provided (at the position B1 of the vibrator 11), and the moving element 17 is in a 90-degree range (A1 of the moving element 17). The position is B1-B2 of the vibrator 11
The range in which the sliding material is supplied is limited to the range of 180 degrees (the shaded area in FIG. 10B). Outside this range, the vibrator (theta) 11 and the moving element (rotor) 17 are in contact with each other, and smooth driving cannot be performed.

Therefore, in this case, FIG.
As shown in the figure, the sliding material supply unit 60-1 is moved to the position of 0 degree (position B1 of the vibrator 11).
2 is preferably provided at a position of 180 degrees (position at B3 of the vibrator 11). By doing so, the range in which the sliding material is replenished is 360 degrees (the shaded area in FIG. 11B), and smooth driving is possible.

Also, as shown in FIG.
Degrees, 180 degrees, and 270 degrees (B1, B of the vibrator 11)
2, B3, B4), the sliding material replenishing section 60-1,
If 60-2, 60-3, and 60-4 are provided, the moving element 17
Can be replenished twice during the 90-degree drive, and can be smoothly driven for a long time. In this case, it is not necessary to arrange at exactly 0 degrees, 90 degrees, 180 degrees, and 270 degrees.
If one is provided in the range of 90 ° to 180 °, one is provided in the range of 180 ° to 270 °, and one is provided in the range of 270 ° to 0 °,
It will have a similar effect. At this time, each of the sliding material replenishing portions 60 may be disposed at substantially the center of the range.

Further, as shown in FIG. 13, when driving in the range of 60 degrees, the sliding material replenishing sections 60-1, 60-2, 60- are located at the positions of 0, 120, and 240 degrees. 3 may be provided. In addition, it is not circular, for example,
In the L1-B4 (combining the first-order longitudinal vibration and the fourth-order bending vibration) type ultrasonic motor, a sliding material supply unit may be arranged near the driving force take-out unit.

(Modifications) Various modifications and changes are possible without being limited to the above-described embodiments, and they are also within the equivalent scope of the present invention. (1) In each of the above embodiments, the ultrasonic motor is the elastic body 1
2 was made of SUS304 and the surface of the moving element 17 was treated with hard alumite. However, the present invention is not limited to this combination, and the material of the elastic body is made of another stainless steel (for example, SUS440). Or phosphor bronze, invar material or the like. Also, the surface treatment of the moving element may be replaced by another surface treatment (for example, electroless nickel, electroless nickel phosphorus).
It may be. Further, the elastic body may be subjected to a surface treatment such as electroless nickel, and the movable member may be subjected to a hard alumite treatment.

(2) In each of the above embodiments, the sliding member is
PTFE sheet or PT composed of 100% PTFE
The FE block has been described as an example.
Even if it is not 0%, if a material containing PTFE is used, a similar effect can be obtained with a similar configuration. (3) Although the ultrasonic motor of the present embodiment uses an ultrasonic motor of nine progressive vibration waves, the ultrasonic motor using other vibrations may be used for the traveling vibration waves of other wave numbers. With a motor or an ultrasonic actuator, a similar effect can be obtained by adopting a similar configuration.

[0050]

As described above, according to the present invention,
A sliding material replenishing section is provided that contacts the driving surface of the vibrating body or the sliding surface of the relative motion member and replenishes the sliding surface with a sliding material that maintains an appropriate sliding state by the sliding operation. The sliding material has always been replenished. For this reason, even if the vibration wave motor is driven for a long time, the effect of the sliding performance by the sliding material is always obtained, and the durability can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an ultrasonic motor 10 according to a first embodiment of the present invention.

FIG. 2 shows a vibrator 11 of the ultrasonic motor 10 according to the first embodiment.
FIG. 2 is an external perspective view showing a moving element 17.

FIG. 3 is a block diagram illustrating an ultrasonic motor drive control device 20 according to the first embodiment.

FIG. 4 is a diagram illustrating a sliding material supply unit of the ultrasonic motor according to the first embodiment.

FIG. 5 is a diagram illustrating a sliding material supply unit of an ultrasonic motor according to a second embodiment.

FIG. 6 is a diagram illustrating a sliding material supply unit of an ultrasonic motor according to a third embodiment.

FIG. 7 is a diagram showing a comparison between the drive characteristics of the vibration wave motor and the frequency-rotation speed characteristics when a metal and a sliding member are attached to each other.

FIG. 8 is a view schematically showing a contact portion between a vibrator and a moving element of the vibration wave motor.

FIG. 9 is a diagram showing the drive characteristics corresponding to the amplitude when the contact portion between the vibrator and the mover of the vibration wave motor is made of metal and when a sliding material is attached.

FIG. 10 is a schematic diagram illustrating an ultrasonic motor 10 according to a fourth embodiment.

FIG. 11 is a schematic diagram illustrating an ultrasonic motor 10 according to a fourth embodiment.

FIG. 12 is a schematic diagram illustrating an ultrasonic motor 10 according to a fourth embodiment.

FIG. 13 is a schematic diagram illustrating an ultrasonic motor 10 according to a fourth embodiment.

[Explanation of symbols]

10 Ultrasonic motor 11 vibrator 12 Elastic body 12a groove 12b Projection 12c drive surface 13 Piezoelectric body 14 Vibration absorbing member 15 Pressure plate 16 Pressure member 17 Moving child 18 Vibration absorbing member 19 Rotating member 20 Drive control device 21 Oscillator 22 Control unit 23 Phase shift unit 24,25 amplifying unit 26 Detector 100 Vibration motor unit 101 Supporting member 102 Press ring 103 Projection 104 bearing 105 Regulation member 30, 40, 50, 60 Sliding material supply section 31, 41 elastic member 51 leaf spring member 32, 42, 52 sliding member

Claims (8)

[Claims] A vibrating body having a piezoelectric body excited by a drive signal and an elastic body which is joined to the piezoelectric body and generates a vibration wave on a driving surface by the excitation; and pressurizing a driving surface of the elastic body. A relative motion member having a sliding surface to be brought into contact with, and a relative motion being generated by the vibration wave, comprising: a driving surface of the vibrating body and / or a sliding surface of the relative motion member. A sliding material that extends from the inside of the vibrating body and / or the relative motion member in the pressing direction and that replenishes the sliding surface and / or the driving surface with a sliding material by a sliding operation based on the relative motion. A vibration wave motor comprising a supply unit. 2. The vibration wave motor according to claim 1, wherein the elastic body has a groove on a driving surface, and the sliding material replenishing section is arranged in the groove. A vibration wave motor characterized by the following. 3. The vibration wave motor according to claim 1, wherein the sliding material replenishing section is provided with a sliding member containing the sliding material, and the sliding member is mounted. A biasing member for pressing the sliding member against the sliding surface of the relative motion member by its elasticity. 4. One of claims 1 to 3
The vibration wave motor according to claim 1, wherein the sliding member is made of PTFE (polytetrafluoroethylene), and the urging member is made of silicon rubber. 5. The vibration wave motor according to claim 1, further comprising: a supporting portion that supports the vibrating body and supports the relative motion member in a state where the relative motion member can be relatively moved. The sliding material replenishing unit includes a sliding member containing the sliding material, a sliding member attached to the sliding member, a base portion fixed to the support portion, and the elasticity of the sliding member to the relative movement member. A vibrating wave motor, comprising: an urging member for bringing the sliding surface into pressurized contact. 6. The vibration wave motor according to claim 1, wherein the elastic body is an annular member having a comb-shaped groove on a driving surface that is substantially perpendicular to a driving direction, and the sliding material is supplied. The vibration wave motor, wherein a plurality of parts are arranged in the groove part. 7. The vibration wave motor according to claim 6, wherein the sliding material replenishing portions are respectively arranged within a range that divides the circumference of the annular member at equal intervals. And a vibration wave motor. 8. The vibration wave motor according to claim 7, wherein the sliding material replenishing portion is disposed substantially at the center of the range.