JP2005278336A - Oscillating body, slide face polishing device and slide face polishing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oscillating body of which the slide face is formed into an arc shape having a curvature at which stable drive is obtained. <P>SOLUTION: The oscillating body 20 has a plurality of protrusions 4, and transmits an excited oscillation in a sending direction to a moving body 12 that contacts with the slide face 3 at the tip of the protrusion 4. A curvature in the sending direction of the moving body of the slide face 3 of the tip of the protrusion 4 is almost equal to a curvature in the vicinity of the belly of a neutral face parallel curve, and set to a value that coincides with or is slightly larger than a curvature at the maximum amplification of a drive oscillation. The curvature of the slide face 3 is not larger than ten times of the curvature of the neutral face parallel curve at a drive limit minimum amplification. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vibrating body, a sliding surface polishing apparatus, and a sliding surface polishing method that transmit excited vibration in a feeding direction to a moving body that is in contact with a sliding surface of a plurality of protrusion tips.

  FIG. 8 is a perspective view showing an external appearance of a general vibrator incorporated in a conventional vibration wave motor. Conventionally, a general vibrating body 420 incorporated in a vibration wave motor includes an elastic body 401, a piezoelectric member 402, and a friction material 405. The elastic body 401 includes a fixing portion 408 for attaching the vibrating body 420 to a housing (not shown) with a screw, an amplitude expanding portion 409 for amplifying the amplitude of vibration excited by the piezoelectric member 402, the fixing portion 408, and the amplitude. The thin portion 410 that connects the enlarged portion 409 is integrally formed. The amplitude expanding portion 409 includes a protrusion 404 and a base portion 411 formed in a comb shape. Between each protrusion 404, the groove part 407 which consists of a space | gap is formed. On the other hand, the piezoelectric member 402 is fixed to the surface on the side opposite to the protrusion of the base portion 411 of the elastic body 401.

  Further, a friction material 405 is fixed to the sliding surface 403 that is the upper surface of each protrusion 404 by bonding, soldering, welding, or the like. The friction material is desirably a material having a high friction coefficient and excellent wear resistance in order to efficiently transmit output, and various organic materials, inorganic materials, and metal materials that meet this condition are used. In addition, an iron-based powder sintered material is used as the material of the elastic body, but it is not limited to this, and there is little energy loss due to vibration such as stainless steel, carbon steel, brass, phosphor bronze, aluminum, zinc, etc. Metal (ie metal with low vibration damping) is suitable. Further, it may be a polymer compound having a high Young's modulus to some extent and a small vibration damping.

  In the vibration wave motor in which such a vibration body is incorporated, the moving body is pressed from the vertical direction and contacts the sliding surface. In recent years, a high-torque vibration wave motor has been demanded, and there has been the following problem when the applied pressure is increased to increase the torque. As a first problem, not only the average surface pressure of the entire sliding surface increases and the durability of the friction material is somewhat deteriorated, but also pressure is concentrated in the vicinity of the edge. Under the local high-pressure environment, the durability of the friction material forming the sliding surface is remarkably deteriorated, and the vicinity of the edge of the friction material may be destroyed. As a second problem, there is a possibility that the edge of the sliding surface and the moving body may seriously damage the sliding surface on the moving body side due to the line contact between the sliding surface and the moving body.

  With respect to the chained problem that the friction material near the edge is damaged due to the concentration of the surface pressure near the edge, and the sliding surface on the moving body side is also damaged due to the damage, Patent Document 1 discloses sliding. An elastic body is shown in which the surface is curved to increase the contact area and reduce the surface pressure. FIG. 9 is a view showing an elastic body in which the sliding surface of the protrusion tip has a curvature. In the figure, 553 is a protrusion, 558 is a sliding surface, 557 is an elastic body, and 556 is a piezoelectric member. In the elastic body 557, by providing the sliding surface 558 with a curvature, the contact state is kept constant and a stable driving force can be obtained. And the problem that a moving body is damaged mechanically by the edge of a sliding surface, a contact area is small, and power transmission cannot be performed efficiently is solved. In this case, the curvature is set to a value smaller than ½ wavelength of the elastic vibration of the elastic body.

  Also, in order to avoid the occurrence of abrasive wear due to the line contact between the edge of the sliding surface at the tip of the protrusion and the moving body, Patent Document 2 provides a rounded edge to avoid line contact. An elastic body shaped as described above is shown. FIG. 10 is a view showing an elastic body in which the edge portion of the sliding surface at the tip of the protrusion is rounded. In the figure, 651 is an elastic body, 652 is a groove, 653 is a protrusion, and 654 is a sliding surface. FIG. 11 is a view showing an elastic body having a chamfered edge portion of the sliding surface at the tip of the protrusion. 751 is an elastic body, 752 is a groove, 753 is a protrusion, and 755 is a sliding surface. The sliding surface 755 does not always vibrate in parallel with the moving body due to the vibration wave. Therefore, the sliding surface 755 comes into contact with the moving body from the edge portion, but by applying such rounding or chamfering to the edge portion, Further, it is possible to prevent the edge portion of the sliding surface at the tip of the protrusion from making a line contact with the moving body, and to reduce abrasive wear.

Further, Patent Document 3 shows that the line contact between the edge of the sliding surface and the moving body is an excitation source that excites unnecessary vibrations on the moving body, so that the line contact should be avoided as much as possible. ing. Moreover, in the manufacturing method described in Patent Document 4, it is shown that the roundness of the edge portion is set. Specifically, the roundness of the edge portion is set to about the same as the amplitude of the drive vibration to about 10 times, and polishing with the size of the abrasive grains and the length of the hair determined by the size of the round shape. It is shown that a round shape is formed with a cloth. Further, in Patent Document 5, R processing of the edge portion is not suitable for mass production, and a sliding material made of a uniform elastic body is provided in the circumferential direction in order to obtain uniform contact between the vibrating body and the moving body. It has been shown.
Japanese Patent No. 2543145 Japanese Patent No. 2563325 JP 2000-23475 A JP-A-8-47270 JP 7-337039 A

  However, in the above-described conventional example, when the curvature is provided at the tip of the protrusion, the magnitude of the curvature is set to a value smaller than ½ wavelength of the elastic vibration of the elastic body, but the explanation is insufficient. Further, a specific means for forming the tip of the protrusion into an arc shape has not been studied. That is, it has been impossible from the viewpoint of mass productivity to mold the protrusion tips of many friction materials one by one into an arc shape. Moreover, it has been very difficult to set the curvature of the arc shape to a target value. Moreover, the manufacturing method which provides roundness cannot be applied to a sliding material having high hardness.

  On the other hand, when the tip of the projection is connected with a sliding material, the neutral surface of the vibration body in the drive vibration is pushed up to the sliding surface side, so that the effect of expanding the amplitude of the projection cannot be obtained sufficiently and the vibration generation efficiency It was lowered.

  Accordingly, the present invention provides a vibrating body in which a sliding surface is formed in an arc shape having a curvature that allows stable driving, a sliding surface polishing apparatus and a sliding surface polishing method for manufacturing the vibrating body. For the purpose.

  The present invention also provides a sliding surface polishing apparatus and a sliding device capable of manufacturing a vibrating body having a sliding surface with rounded edges so as to be compatible with high hardness friction materials and suitable for mass production. It is another object to provide a dynamic surface polishing method.

  In order to achieve the above object, a vibrating body according to the present invention has a plurality of protrusions, and transmits the excited vibration in the feeding direction to a moving body that contacts the sliding surface of the protrusion tip. The sliding surface is formed in an arc shape, and the curvature of the sliding surface in the moving body feeding direction is substantially equal to the curvature in the vicinity of the antinode of the neutral plane parallel curve.

  The sliding surface polishing apparatus is a sliding surface polishing apparatus that polishes a plurality of protrusions provided on the vibrating body in a state where the sliding surface that contacts the moving body is pressed against the polishing surface. A holding means for holding the vibrating body in a state in which power can be supplied to the piezoelectric member that excites vibrations, and polishing for polishing the sliding surface pressed against the polishing surface in an arc shape while exciting vibration to the vibrating body And means for shaping the sliding surface so that the curvature of the sliding surface to be polished is constant in the moving body feeding direction.

  Further, the sliding surface polishing method is a sliding surface polishing method in which a plurality of protrusions provided on the vibrating body are polished in a state where the sliding surface contacting the moving body is pressed against the polishing surface. A holding step for holding the vibrating body in a state where power can be supplied to a piezoelectric member that excites vibrations, and polishing for polishing the sliding surface pressed against the polishing surface into an arc shape while exciting vibration to the vibrating body And forming the sliding surface so that the curvature of the sliding surface to be polished is constant in the moving body feeding direction.

  According to the vibrating body according to claim 1 of the present invention, the curvature in the moving body feed direction of the sliding surface is substantially equal to the curvature in the vicinity of the antinode of the neutral plane parallel curve. The sliding surface is formed into an arc shape. By using this vibrating body, it is possible to achieve a stable drive that is excellent in durability, does not generate abnormal noise, and does not deteriorate in durability even when the pressure is increased for higher torque. be able to.

  According to the sliding surface polishing apparatus of the sixth aspect, the curvature after the polishing finish can be determined, and a vibrating body having such a curvature can be manufactured. Moreover, a vibrating body can be manufactured so as to be compatible with a high-hardness friction material and suitable for mass production.

  Embodiments of a vibrator, a sliding surface polishing apparatus, and a sliding surface polishing method according to the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a perspective view showing an appearance of a vibrating body incorporated in a vibration wave motor according to the first embodiment. The vibrating body 20 includes an elastic body 1, a piezoelectric member 2, and a friction material 5. The elastic body 1 includes a fixing portion 8 for attaching the vibrating body 20 to a housing (not shown) with screws, an amplitude expanding portion 9 for amplifying the amplitude of vibration excited by the piezoelectric member 2, a fixing portion 8 and The thin-walled portion 10 that connects the amplitude-enlarging portion 9 is integrally formed. The amplitude expanding portion 9 includes a protrusion 4 and a base portion 11 formed in a comb shape. Between each protrusion 4, the groove part 7 which consists of a space | gap is formed. On the other hand, the piezoelectric member 2 is fixed to the surface on the side opposite to the protrusion of the base portion 11 of the elastic body 1.

  A friction material 5 is fixed to the sliding surface 3 that is the upper surface of each protrusion 4 by bonding, soldering, welding, or the like. The friction material is desirably a material having a high friction coefficient and excellent wear resistance in order to efficiently transmit output, and various organic materials, inorganic materials, and metal materials that meet this condition are used. Moreover, although the iron-based powder sintered material is used as a material of the elastic body 1, it is not limited to this, For example, energy loss by vibration, such as stainless steel, carbon steel, brass, phosphor bronze, aluminum, zinc, etc. Less metal (that is, metal with low vibration damping) is suitable. Further, it may be a polymer compound having a high Young's modulus to some extent and a small vibration damping.

  Next, the curvature of the sliding surface at the tip of each protrusion will be considered. FIG. 2 is a view of the contact state between the sliding surface at the tip of the protrusion and the moving body in the vicinity of the antinode of the driving vibration as viewed from the outer diameter side of the vibrating body. In the figure, 12 is a moving body. FIG. 4A shows a case where the sliding surface of the protrusion is not formed in an arc shape. In the figure, 4a is a protrusion. In actual contact, the line contact is not performed only at the edge portion, but the sliding surface on the moving body side is deformed so as to follow the sliding surface on the vibrating body side. ing. FIG. 5B shows a case where the sliding surface of the protrusion is formed in an arc shape and the sliding surface is made to substantially coincide with the neutral plane parallel curve together with the sliding surface on the moving body side. In the figure, 4b is a protrusion. Here, the neutral plane parallel curve refers to a curve that passes through the vibrating body sliding surface and is parallel to the curved surface of the vibrating body neutral surface that represents drive vibration (see the wavy line m in FIG. 4). Further, it is known from experiments that the curvature of the sliding surface on the moving body side substantially matches the neutral plane parallel curve.

  The present inventors have pressed the sliding surface on the movable body side against the sliding surface on the vibrating body side having the shape shown in FIGS. The reaction force was calculated. FIG. 3 is a graph showing the moving body reaction force distribution. The horizontal axis of this graph represents the phase (θangle) in the moving body feed direction of the vibrating body. On the other hand, the vertical axis of the graph represents the magnitude of the reaction force distribution (Repulsive Force) from the sliding surface of the vibrating body against the pressing of the moving body at each node of the analysis model. In the static analysis calculation result of the present inventors, the moving body reaction force distribution in FIG. 2A is as shown by a curve a. The moving body reaction force distribution in FIG. 2B is as shown by the curve b. From these calculation results, by making the curvature of the sliding surface of the protrusion 4 substantially coincide with the curvature in the vicinity of the antinode of the driving vibration in the neutral plane parallel curve, the surface pressure in the vicinity of the edge is reduced and the local pressure due to the applied pressure is reduced. It can be seen that the high pressure environment can be suppressed.

  However, as shown by the curve b, the moving body reaction force distribution in FIG. 2B is still incomplete because the reaction force is still large at the edge portion. On the other hand, when the edge portion of the arc-shaped friction surface (sliding surface) is rounded, the reaction force distribution of the moving body becomes uniform as shown by the curve c. FIG. 2D shows a case where the edge portion is rounded. As described above, there are two reasons why a better result is obtained when the edge portion is rounded. One of them is that the influence of the phenomenon of stress concentration near the edge as seen in contact between two planes is mitigated. The other is that the influence of the phenomenon that the bending point of the moving body is generated near the edge due to the moving body slacking in the groove between the protrusions is mitigated.

  Thus, providing the edge portion with roundness is effective in improving the durability of the motor in order to reduce the influence of the above two phenomena in addition to the abrasive wear of the moving body. In the present embodiment, by forming the sliding surface into such a shape (see FIG. 2D), it is possible to realize a smooth and stable drive that is excellent in durability and does not generate abnormal noise, and has high torque. Therefore, it is possible to obtain a vibration wave motor whose durability does not deteriorate even when the pressure is increased.

  When used as a vibration wave motor, the amplitude of the drive vibration changes depending on the rotation speed or output of the motor, but at the same time, the curvature of the neutral plane parallel curve also changes. FIG. 4 is a diagram showing a driving state of the moving body by the vibrating body in the vibration wave motor when there is no load. As shown in FIG. 3A, the amplitude of the driving wave is the largest at the highest speed rotation, and the curvature of the neutral plane parallel curve is also increased at this time. When the rotational speed is lowered from this state, the amplitude of the driving wave becomes smaller and the curvature of the neutral plane parallel curve becomes smaller as shown in FIG. When the amplitude falls below a certain value, the vibrating body and the moving body are almost in contact with each other, and the motor stops. The amplitude at this time is the drive limit minimum amplitude, and the curvature is the drive limit minimum curvature.

  If the curvature of the sliding surface is matched to the curvature of the neutral plane parallel curve at the drive amplitude that is most desired to be used as a motor, the same rotational speed or output will result due to deterioration of the sliding surface or reduced efficiency due to heat generation. However, when a larger drive amplitude is required, there is a possibility that a line contact occurs at the edge portion, and a problem such as generation of abnormal noise occurs. For this reason, at least, the curvature of the sliding surface must be formed in accordance with the curvature of the neutral plane parallel curve that requires the maximum amplitude under the actual driving environment. Thereby, line contact can be avoided under all driving conditions, and stable driving can be obtained.

  Further, when driving at low speed, that is, when the driving wave has a low amplitude, the curvature on the moving body side is small, but the curvature on the sliding surface on the vibrating body side is the curvature at the maximum amplitude. For this reason, as shown in FIG. 2 (C), the contact between the vibrating body having the sliding surface and the moving body shown in FIG. Get smaller. During driving, a state in which the sliding surfaces of all the plurality of protrusions are not in contact with the moving body at any place may be instantly created. At this moment, there is no torque transmission from the vibrating body to the moving body, and the driving becomes unstable. Therefore, in order to reliably transmit torque from the vibrating body to the moving body and obtain a stable drive, the curvature of the sliding surface at the tip of the protrusion of the vibrating body is set so as to satisfy the condition shown in Equation (1). There is a need to.

Sliding surface curvature / driving limit minimum curvature <10 (1)
Next, as discussed above, a sliding surface polishing apparatus and a polishing method thereof for forming a sliding surface of a vibrating body into an arc shape with rounded edges are shown. FIG. 5 is a perspective view showing the configuration of the sliding surface polishing apparatus. This sliding surface polishing apparatus includes a vibrating body holding unit 41 and a polishing unit 42. In the vibrating body holding portion 41, the vibrating body 20 is fixed to the base 22 with a screw that passes through the fixing portion 8. The base 22 is attached to the lower surface of the case 23, and the case 23 is attached to the holder 25 via the rotary connector 24. A film substrate 29 is connected between the rotary connector 24 and the piezoelectric member 2 of the vibrating body 20. On the other hand, the polishing unit 42 includes a turntable 26, and a soft layer 27 is provided on the upper surface thereof. Furthermore, a wrapping film 28 is stuck on the soft layer 27.

  The polishing method is the same as a general method. A turntable 26 having a lapping film 28, which is a polishing layer containing abrasive grains, is attached to a smooth upper surface, is rotated at an appropriate speed so that the sample does not flutter, and polishing is performed on the turntable 26. By pressing the holder 25 toward the turntable 26 while dropping the liquid, the sliding surface of the vibrating body 20 is pressed against the abrasive grains and brought into contact therewith. When the holder 25 is driven by a drive source (not shown), the vibrating body 20 slides (slides) repeatedly on the turntable 26 in the radial direction together with the holder 25. Here, a wrapping film (manufactured by Sumitomo 3M Limited) is used as the polishing layer. In particular, in this embodiment, since the friction material is a ceramic material, a wrapping film of diamond abrasive grains was used.

  As described above, the vibrating body 20 is fixed to the base 22 with a screw that passes through the fixing portion 8, and is supplied with power through the flexible substrate 29 connected to the rotary connector 24. Then, by polishing the vibrating body 20 while exciting the vibration, the sliding surface is formed into an arc shape with a constant curvature in the moving body feeding direction. This polishing method is referred to as vibration polishing, and the amplitude of vibration excited by the vibrating body during polishing is referred to as polishing amplitude. The polishing amplitude may be considered to be the same as the vibration amplitude in the actual driving state. When the sliding surface is formed into an arc shape when the driving vibration is maximum, the amplitude value of the driving vibration at that time is set as the polishing amplitude. And polish.

  Molding by this polishing proceeds with a distribution in the amount of polishing until the curvature determined by the polishing amplitude, but as the polishing proceeds to that curvature, the distribution of reaction force against the pressing force on the sliding surface becomes uniform, and at this time Thus, the forming of the arc shape is practically stopped. Thereafter, only the edge forming proceeds, and the formation of the sliding surface having a desired arc shape is completed. Thus, in vibration polishing, the curvature after polishing can be determined only by setting the polishing amplitude without performing excessive polishing.

  Here, the polishing amplitude will be described. The amplitude during polishing tends to change due to the rigidity of the system between the vibrating body and the turntable determined by the pressing force on the polishing surface. In addition, the rigidity of the system changes and the polishing amplitude also changes when the contact state changes such that the molding by polishing proceeds and the contact area of the sliding surface increases. Therefore, in order to keep the polishing amplitude value constant, it is necessary to control the input signal to the vibrating body 20. In this embodiment, the polishing amplitude is measured using an output signal from a sensor phase (not shown) provided on the piezoelectric member 2 of the vibrating body 20, and feedback control is performed. Further, as a means for detecting the polishing amplitude, a non-contact type vibration sensor or the like may be used. Thus, by controlling the polishing amplitude, the curvature of the sliding surface can be set to a desired value.

  Further, in general, in polishing using a wrapping film, tension is applied to the wrapping film in order to prevent dust from being caught between the wrapping film and the polishing plate and causing edge dripping. In the present embodiment, a Teflon (registered trademark) sheet having a thickness of 0.5 mm is sandwiched between the wrapping film and the polishing plate as the soft layer 27 for the purpose of intentionally causing a fringing.

  By providing this soft layer, the edge portion of the sliding surface sinks, and the edge portion is polished more strongly than the region inside the edge, causing dripping. The amount of drooping is adjusted by the amount of pressing force between the holder and the polishing plate. The greater the pressing force, the easier it will droop, and increasing the pressing force will increase the amount of polishing in the internal area, but there is a difference between the amount of dripping with respect to the pressing force and the increment of the polishing amount in the internal area. It is possible to mold at once by adjusting within the range. Of course, the edge polishing amount may be adjusted by applying tension to the wrapping film. As described above, since the edge and the arc shape can be formed at a time, this manufacturing method is suitable for mass production. As a result, a sliding surface having a rounded edge (edge) as shown in FIG. 2D is formed.

  Further, when determining the end of polishing, in this embodiment, an output signal from the sensor phase is confirmed. The contact of the edge part with high surface pressure becomes an excitation source that causes unnecessary vibrations even for the vibrating body, so when checking the waveform of the output signal from the sensor phase, the vicinity of the edge contacted at the start of polishing. A pulse-like signal is confirmed at the timing. However, as the polishing progresses, the signal level decreases, and it is determined that the sliding surface has a shape without the influence of the edge when the signal level falls within a substantially negligible range. As described above, the shape of the sliding surface after the polishing is an arc shape having a curvature determined by the polishing amplitude, and a round shape that alleviates the surface pressure increase phenomenon near the edge.

  Furthermore, for a while after the start of polishing, the polishing time can be shortened by setting the amplitude value to be larger than the polishing amplitude for obtaining the final curvature. However, if it is set too large, problems such as breakage of the piezoelectric member or destruction of the edge portion of the friction material occur.

  In the present embodiment, the friction material 5 is made of a hard ceramic material and is manufactured as follows. That is, a ceramic material sheet extracted into a donut shape is fired to form a ceramic ring. After the ceramic ring is bonded to the upper surface of the protrusion of the elastic body, the groove is cut by laser processing to produce the friction material 5. The Here, when comparing the so-called “cutting after bonding” and “adhesion after cutting”, the “adhesion after cutting” is likely to cause a difference in the thickness of the adhesive layer of the friction material at each protrusion, and sticking. At that time, the height varies and the flatness is poor. In “adhesion after cutting”, flatness must be obtained as the first polishing step, and then the vibration polishing step must be performed as the second polishing step, which is not appropriate in terms of cost.

  Thus, according to the vibrating body of the first embodiment, the curvature of the sliding surface in the moving body feed direction is substantially equal to the curvature in the vicinity of the antinode of the neutral plane parallel curve, so that stable driving can be obtained. The sliding surface is formed into an arc shape having a curvature. By using this vibrating body, it is possible to achieve a stable drive that is excellent in durability, does not generate abnormal noise, and does not deteriorate in durability even when the pressure is increased for higher torque. be able to. Further, since the edge of the sliding surface is formed in a round shape, the reaction force distribution from the moving body can be made more uniform. Further, line contact is avoided under all driving conditions, and stable driving can be obtained. Since one of the sliding surfaces of all the protrusions is in contact with the moving body, a stable drive can always be obtained.

  Moreover, the curvature after the polishing finish can be determined, and a vibrating body having such a curvature can be manufactured. Moreover, a vibrating body can be manufactured so as to be compatible with a high-hardness friction material and suitable for mass production. Further, the curvature can be set to a target value by setting the polishing amplitude. Both round shape and arc shape can be formed so as to be suitable for mass production.

[Second Embodiment]
The sliding surface of the vibrating body according to the second embodiment has an arc shape with a curvature corresponding to the sliding width, in addition to the shape considered in the first embodiment. The same reference numerals are used for the same constituent elements as those in the first embodiment.

  First, consider the width of the sliding surface of the vibrating body. In the vibrating body 20 shown in FIG. 1, since the primary vibration is excited in the radial direction, the vibration amplitude on the outer peripheral side is large. Further, the wavelength of out-of-plane vibration that is the driving mode of the vibrating body is also longer on the outer peripheral side in proportion to the diameter of the sliding surface (sliding diameter). For this reason, the neutral plane parallel curve varies depending on the sliding diameter, and the optimum curvature of the arc shape formed on the sliding surface also varies depending on the sliding diameter. In order to increase the contact area of the sliding surface and reduce the average surface pressure, the sliding width must be increased according to the diameter. At this time, it is necessary to make an arc shape with an optimal curvature within the sliding width at each diameter. That is, the neutral surface parallel curve on the outer peripheral side becomes a circular arc with a large curvature, so that the curvature of the sliding surface on the outer peripheral side is increased.

  As a result, even a vibration wave motor with a wide sliding width can achieve a smooth drive that is excellent in durability and does not generate abnormal noise. In addition, since the average surface pressure is reduced by increasing the sliding width, the applied pressure between the vibrating body and the moving body can be increased, and the torque can be increased.

  FIG. 6 is a perspective view showing a configuration of a sliding surface polishing apparatus according to the second embodiment. The sliding surface polishing apparatus 140 according to the second embodiment includes a vibrating body holding unit 41 and a polishing unit 142, and the configuration of the vibrating body holding unit is the same as that of the first embodiment. The polishing unit 142 includes a polishing board 32 having an outer diameter substantially equal to that of the vibrating body 20, a polishing support 33 that supports the polishing board 32, and a wrapping film 31 that is attached to the upper surface of the polishing board 32.

  As described above, when the width of the sliding surface of the vibrating body 20 is expanded in accordance with the diameter, the neutral plane parallel curve differs depending on the sliding diameter, and the optimal curvature of the arc shape formed on the sliding surface is also It depends on the sliding diameter. Therefore, it is desirable to make the arc shape of the sliding surface having a different curvature in the radial direction with an optimal curvature corresponding to the sliding diameter.

  In the second embodiment, an environment close to actual driving is created in order to accurately create an ideal arcuate shape of the sliding surface. That is, the material of the polishing board 32 is a metal material having bending rigidity comparable to that of the moving body actually used as the vibration wave motor with respect to the out-of-plane bending vibration of the vibrating body 20. Alternatively, the moving body can be used as it is.

  However, when the width (length) of the sliding surface in the radial direction is larger than that of the moving body (vibrating body> moving body), only a part of the friction material of the vibrating body is polished, and the moving body is attached. It is strongly influenced by the eccentricity of the side and the side force applied to the moving body. For this reason, a polishing disc is used in which the radial width (length) of the sliding surface is smaller than that of the moving body (vibrating body <moving body), and the same effect is always obtained.

  As described above, according to the second embodiment, it is possible to widen the radial width of the sliding surface, and to form the sliding surface having an arc shape with an optimal curvature according to the diameter. it can.

[Third Embodiment]
FIG. 7 is a perspective view showing the configuration of the sliding surface polishing apparatus in the third embodiment. The sliding surface polishing apparatus 240 according to the third embodiment can manufacture sliding surfaces of a plurality of vibrating bodies at a time in order to increase mass productivity, and includes a vibrating body holding unit 41 and a polishing unit 242. . The configuration of the vibrating body holding unit is the same as that of the first and second embodiments, but a rotating mechanism (not shown) is provided in the vibrating body holding unit in order to rotationally drive the vibrating body. .

  The polishing unit 242 includes a polishing board 52 pressed by the vibrating body 20, a wrapping film 51 that is stretched over the polishing board 52 and is in contact with the vibrating body 20, and a motor 53 that sends the wrapping film 51. A brake 44 for applying a certain tension to the wrapping film 51 is provided. When polishing, the location of the wrapping film 51 once used for polishing is shifted so that the polishing operation is performed efficiently.

  In this embodiment, since the polishing board 52 is not rotatable, as described above, the polishing body 52 is uniformly polished while rotating the vibration body holding portion 41 that rotatably holds the vibration body 20. At this time, the rotational speed of the vibrating body is reproduced to a value corresponding to the relative speed of the vibrating body and the moving body when the motor is actually driven with the same amplitude value as the polishing amplitude. As the driving force, the vibration generated in the vibrating body during polishing is used, but when a sufficient relative speed cannot be obtained by polishing liquid or the like, the output of the external motor is transmitted to the case 23 via the belt. By doing so, you may assist.

  In an actual vibration wave motor that continuously rotates in a certain direction, the phenomenon that the vibration phase of the moving body lags behind the vibration phase of the vibrating body occurs, and when the wear amount of the friction surface is viewed in the moving body feed direction, the wear amount is biased. Arise. This is because the surface pressure of the sliding surface is uneven, and this surface pressure distribution must be relaxed in order to obtain smoother driving. Therefore, polishing in a state close to the contact in the actual drive state while reproducing the relative speed between the elastic body and the mobile body close to the actual drive state makes the stress distribution in the moving body feed direction of the sliding surface uniform. There is an effect to. As described above, according to the third embodiment, the uneven surface pressure in the moving body feeding direction on the sliding surface can be eliminated, and uneven wear can be prevented.

  The above is the description of the embodiments of the present invention. However, the present invention is not limited to the configurations of these embodiments, and the functions shown in the claims or the functions of the configurations of the embodiments can be achieved. Anything is applicable.

It is a perspective view which shows the external appearance of the vibrating body incorporated in the vibration wave motor in 1st Embodiment. It is the figure which looked at the contact state of the sliding surface of the front-end | tip of a protrusion and the moving body in the vicinity of the antinode of drive vibration from the outer diameter side of the vibrating body. It is a graph which shows a mobile body reaction force distribution. It is a figure which shows the drive state of the moving body by the vibrating body in the vibration wave motor at the time of no load. It is a perspective view which shows the structure of a sliding surface grinding | polishing apparatus. It is a perspective view which shows the structure of the sliding surface grinding | polishing apparatus in 2nd Embodiment. It is a perspective view which shows the structure of the sliding surface grinding | polishing apparatus in 3rd Embodiment. It is a perspective view which shows the external appearance of the general vibration body integrated in the conventional vibration wave motor. It is a figure which shows the elastic body which gave the curvature to the sliding surface of the protrusion tip. It is a figure which shows the elastic body which made the edge part of the sliding surface of a processus | protrusion round. It is a figure which shows the elastic body by which the edge part of the sliding surface of the protrusion tip was chamfered.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Elastic body 2 Piezoelectric member 3 Sliding surface 4 Protrusion 20 Vibrating body 26 Turntable 27 Soft layer 28 Lapping film

Claims (15)

In the vibrating body having a plurality of protrusions and transmitting the excited vibration in the feeding direction to the moving body that contacts the sliding surface of the protrusion tip,
The vibrating body is characterized in that the sliding surface is formed in an arc shape, and the curvature of the sliding surface in the moving body feeding direction is substantially equal to the curvature in the vicinity of the antinode of the neutral plane parallel curve.   The vibrating body according to claim 1, wherein an edge portion of the sliding surface is formed in a round shape.   2. When incorporated in a vibration wave motor, the curvature of the sliding surface in the moving body feed direction is a curvature that is equal to or slightly larger than the curvature at the maximum amplitude of the drive vibration. The vibrator described.   4. The vibrating body according to claim 3, wherein the curvature of the sliding surface in the moving body feeding direction is not more than 10 times the curvature of the neutral plane parallel curve at the drive limit minimum amplitude.   The vibrating body according to claim 3, wherein the curvature of the sliding surface in the moving body feeding direction varies depending on the diameter of the sliding surface. A sliding surface polishing apparatus that polishes a plurality of protrusions provided on the vibrating body in a state in which the sliding surface that contacts the moving body is pressed against the polishing surface,
Holding means for holding the vibrating body in a state in which power can be supplied to the piezoelectric member that excites vibration of the vibrating body;
Polishing means for polishing the sliding surface pressed against the polishing surface into an arc shape while exciting vibrations in the vibrator,
The sliding surface polishing apparatus, wherein the sliding surface is shaped so that the curvature of the sliding surface to be polished is constant in the moving body feeding direction.   The sliding surface polishing apparatus according to claim 6, further comprising amplitude detection means for detecting a polishing amplitude that is a vibration amplitude of the vibrating body, and controlling the detected polishing amplitude to be constant. The polishing means has the polishing surface comprising a polishing layer containing abrasive grains, a high hardness elastic body having flatness, and a soft layer provided between the polishing layer and the high hardness elastic body. And
The sliding surface polishing apparatus according to claim 6 or 7, wherein the sliding surface is molded so that the curvature of the sliding surface becomes constant, and at the same time, the sliding surface is shaped so as to cause an edge.   9. The sliding surface polishing apparatus according to claim 8, wherein the high-hardness elastic body is made of a metal material having a bending rigidity comparable to that of the moving body.   The holding means rotatably holds the vibrating body, and the polishing means reproduces the relative speed between the vibrating body, which is rotatably held by the holding means, and a state close to actual driving. The sliding surface polishing apparatus according to claim 6, wherein the polishing is performed while polishing. A sliding surface polishing method for polishing a plurality of projections provided on the vibrating body, with the sliding surface contacting the moving body pressed against the polishing surface,
A holding step of holding the vibrating body in a state in which power can be supplied to the piezoelectric member that excites vibration of the vibrating body;
A polishing step of polishing the sliding surface pressed against the polishing surface into an arc shape while exciting vibrations in the vibrator;
A sliding surface polishing method, wherein the sliding surface is formed so that a curvature of the sliding surface to be polished in a moving body feeding direction is constant.   12. The sliding surface polishing method according to claim 11, further comprising an amplitude detection step of detecting a polishing amplitude that is a vibration amplitude of the vibrating body, wherein the detected polishing amplitude is controlled to be constant.   In the polishing step, the polishing surface including a polishing layer containing polishing abrasive grains, a high-hardness elastic body having flatness, and a soft layer provided between the polishing layer and the high-hardness elastic body is used. 13. The sliding surface according to claim 11 or 12, wherein the sliding surface is polished and molded so that the curvature of the sliding surface is constant, and at the same time, the sliding surface is molded to have an edge. Sliding surface polishing method.   The sliding surface polishing method according to claim 13, wherein the high-hardness elastic body is made of a metal material having a bending rigidity comparable to that of the moving body.   In the holding step, the vibrating body is rotatably held, and in the polishing step, polishing is performed while reproducing a relative speed between the movable body that is rotatably held and is close to actual driving. The sliding surface polishing method according to claim 11, wherein:

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