JP2022152714A - Vibration type actuator, apparatus, contact body, and manufacturing method thereof - Google Patents

Abstract

To provide a contact body that makes contact with a vibrator in a vibration type actuator, has a metal sintered compact that makes contact with the vibrator and has high corrosion resistance.SOLUTION: A contact body 6 that makes contact with a vibrator 2 in a vibration type actuator 1 is made of a sintered compact 6a obtained by sintering metal and has a resin-impregnated portion 6c in which epoxy resin has been impregnated, on at least one of surfaces of the sintered compact 6a. The resin-impregnated portion 6c has a first resin-impregnated surface 6e covered by epoxy resin, and a second resin-impregnated surface 6f not covered by epoxy resin, and has a structure in which the first resin-impregnated surface 6e and the second resin-impregnated surface 6f are flush with each other.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to a vibration type actuator, a device provided with the vibration type actuator, a contact body used in the vibration type actuator, and a manufacturing method thereof.

A vibration type actuator is known in which a vibrating body and a contact body are brought into pressure contact with each other, a predetermined vibration is excited in the vibrating body, and a friction driving force is applied from the vibrating body to the contact body, thereby relatively moving the vibrating body and the contact body. ing. Such a vibration type actuator has a large holding force because it utilizes the frictional force caused by the contact between the vibrating body and the contact body. Demonstrate the ability to maintain relationships.

Various proposals have been made for the material used for the contact body that constitutes the vibration type actuator. For example, Patent Literature 1 proposes using a stainless steel sintered body impregnated with a resin mixed with hard particles as a contact body. In the contact body described in Patent Document 1, the impregnated resin as a sliding material contributes to improving wear resistance and maintaining a high coefficient of friction. A high coefficient of friction can be maintained even after being exposed to the environment.

JP 2017-225333 A

In the contact body described in Patent Document 1, abrasion powder generated by friction sliding between the contact body and the vibrating body when the vibration type actuator is driven adheres to the periphery of the friction sliding surface of the contact body. When the contact body is placed in a high-humidity environment in such a state, the abrasion powder has a large surface area, so it tends to retain moisture. Become. Such a decrease in corrosion resistance causes problems such as a decrease in driving force due to falling off of metal particles from the friction sliding surface and contamination of equipment due to falling off particles turning into dust.

SUMMARY OF THE INVENTION An object of the present invention is to provide a contact body that contacts a vibrating body in a vibration type actuator, has a metal sintered body that contacts the vibrating body, and has high corrosion resistance.

A contact body according to the present invention is a contact body in contact with a vibrating body in a vibration type actuator, the contact body having a sintered metal body in contact with the vibrating body and impregnated with a first resin. at least one surface of the sintered metal body, and the resin-impregnated portion includes a first resin-impregnated surface coated with a second resin and a resin-impregnated surface coated with the second resin. The first resin-impregnated surface and the second resin-impregnated surface are flush with each other.

According to the present invention, it is possible to provide a contact body that is in contact with a vibrating body in a vibration-type actuator, has a metal sintered body that comes into contact with the vibrating body, and has high corrosion resistance.

It is a figure explaining the schematic structure of the vibration-type actuator which concerns on embodiment. FIG. 4 is a diagram for explaining vibrations excited in a vibrating body of a vibrating actuator; It is a figure explaining the manufacturing method of the contact body of a vibration-type actuator. It is a figure explaining the structure of the contact body in the former and this embodiment. It is a figure which shows the structural example of an imaging device provided with a vibration-type actuator. It is a figure which shows the structural example of the robot provided with a vibration-type actuator.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1(a) is a diagram for explaining a schematic configuration of the vibration type actuator 1. FIG. A vibration-type actuator 1 has a vibrating body 2 and a contact body 6 that contacts the vibrating body 2 . The vibrating body 2 includes a flat plate-like elastic body 3, a piezoelectric element 4 as an electro-mechanical energy conversion element adhered to one surface of the elastic body 3, and two piezoelectric elements provided on the other surface of the elastic body 3. It has a protrusion 5 .

FIG. 1(b) is a cross-sectional view of the protrusion 5 provided on the vibrating body 2. FIG. The projecting portion 5 is a portion of the vibrating body 2 that becomes a contact portion with respect to the contact body 6 . The projecting portion 5 has a spring property in order to prevent abnormal noise from being generated during driving. In addition, the cross-sectional area of the protrusion 5 in the plane parallel to the contact surface 5a with the contact body 6 of the protrusion 5 increases as the distance from the contact surface 5a side increases so that the change in spring rigidity due to wear becomes small. have.

The term "contact body" refers to a member that contacts the vibrating body and moves relative to the vibrating body due to vibration generated in the vibrating body. The contact between the contact body and the vibrating body is not limited to direct contact with no other member interposed between the contact body and the vibrating body. The contact between the contact body and the vibrating body is an indirect contact in which another member is interposed between the contact body and the vibrating body if the vibration generated in the vibrating body causes the contact body to move relative to the vibrating body. good too. "Another member" is not limited to a member independent of the contact member and the vibrating member (for example, a high-friction material made of a sintered body). The "other member" may be a surface-treated portion formed on the contact body or vibrating body by plating, nitriding, or the like.

FIG. 2(a) is a diagram for explaining the first vibration mode (hereinafter referred to as "A mode") of the two bending vibration modes excited in the vibrating body 2. FIG. A common electrode (whole surface electrode) (not shown) is formed on the surface of the piezoelectric element 4 on the side of the elastic body 3, and the surface on the opposite side of the surface on the side of the elastic body 3 is divided into two equal parts in the length direction for driving (not shown). Electrodes are formed.

The A mode is a secondary bending vibration in the longitudinal direction (X direction) of the vibrating body 2, and has three nodal lines substantially parallel to the lateral direction (Y direction (width direction)) of the vibrating body 2. ing. By applying an alternating voltage with a predetermined frequency and a phase difference of 180° to the driving electrodes of the piezoelectric element 4, the vibrating body 2 can be excited to vibrate in A mode. The projecting portion 5 is arranged in the vicinity of a node in the A-mode vibration, and performs reciprocating motion in the X direction when the vibrating body 2 is excited by the A-mode vibration.

FIG. 2(b) is a diagram for explaining the second vibration mode (hereinafter referred to as "B mode") of the two bending vibration modes excited in the vibrating body 2. As shown in FIG. The B mode is primary bending vibration in the lateral direction (Y direction) of the vibrating body 2 and has two nodal lines substantially parallel to the longitudinal direction (X direction). B-mode vibration can be excited in the vibrating body 2 by applying an alternating voltage having a predetermined frequency and the same phase to the driving electrodes of the piezoelectric element 4 . The protrusion 5 is arranged near the antinode of the B-mode vibration, and when the vibrating body 2 is excited by the B-mode vibration, the protrusion 5 reciprocates in the axial direction (Z direction). conduct.

The vibrating body 2 is configured such that the nodal line in the A mode and the nodal line in the B mode are substantially orthogonal in the XY plane. A flexible substrate (not shown) is adhered to the piezoelectric element 4, and by supplying an alternating current to the piezoelectric element 4 through the flexible substrate, it is possible to simultaneously excite vibrations in the A mode and the B mode in the vibrating body 2. can. At this time, by exciting the A-mode and B-mode vibrations with a predetermined phase difference, it is possible to generate an elliptical motion in the ZX plane at the tip of the protrusion 5 .

In the vibration type actuator 1 , each of the three vibrating bodies 2 is arranged such that the straight line connecting the two protrusions 5 is the tangential line of the ring-shaped contact body 6 and is in contact with the contact body 6 . Therefore, while the contact member 6 is rotatably supported in the direction of rotation (the circumferential direction of the contact member 6) indicated by the arrow in FIG. The contact member 6 can be frictionally driven by the protrusion 5 to rotate in its circumferential direction.

In FIG. 1, illustration of a supporting member that rotatably supports the contact member 6, a holding member that holds the vibrating member 2, a pressurizing means for bringing the vibrating member 2 and the contact member 6 into contact, etc. is omitted. ing. In this embodiment, the vibrating body 2 is fixed and the contact body 6 is rotatable, but conversely, the contact body 6 is fixed and the three vibrating bodies 2 are rotated together with the holding member. is also possible.

Next, a method for manufacturing the contact member 6 will be described. 3A and 3B are diagrams for explaining a method for manufacturing the contact body 6. FIG. FIG. 3(e) is a cross-sectional view of the contact member 6 taken along line AA shown in FIG. 1(a), the left side being the inner diameter side and the right side being the outer diameter side.

FIG. 3(a) is a cross-sectional view of a sintered body 6a used as a base material (substrate) of the contact body 6. FIG. In this embodiment, a metal sintered body made of martensitic stainless steel equivalent to SUS420J2 is used as the base material of the contact member 6 . Note that FIG. 3(a) and FIGS. 3(b) to (d), which will be described later, are represented by the same cross section as FIG. 3(e).

The sintered body 6a is manufactured by a process (sintering process) in which a compact of raw material powder, which is a mixture of SUS410L powder having a particle size of 150 μm or less and carbon powder, is held at a predetermined temperature below the melting point to bond the powders together. be. The sintered density ranges from 6.1 g/ml (=6.1 kg/dm ³ ) to 6.6 g/ml (=6.6 kg/dm ³ ).

The sintered body 6a has a Vickers hardness of 550HV0.2 or more, preferably 600HV0.2 or more. The reason for this is that while the wear resistance of the friction sliding surface against the vibrating body 2 is ensured, the pores are closed or the pore area is reduced due to the plastic flow of the metal portion that occurs in the subsequent polishing process. This is to prevent The hardness of the sintered body 6a can be adjusted by sinter hardening or quenching, which is heat treatment in the sintering process by adjusting the cooling rate in the sintering furnace. In addition, the Vickers hardness measurement of the sintered body 6a was performed with a micrometer with a test force of 200 g (=0.2 kg) against the metal surface polished after impregnating the resin in order to reduce the influence of the pores of the sintered body 6a. I'm doing it with Vickers.

The cross-sectional shape of the sintered body 6a is substantially rectangular as shown in FIG. 3(a). The flatness of the "sintered surface 6aa") may be about 100 μm. In addition, thickness unevenness may also occur between lots in which the sintering process is mainly performed. Therefore, in order to improve the flatness of the contact surface with respect to the vibrating body 2 and the surface on the opposite side (back surface), correct the thickness of the contact body 6 to a predetermined value, and further adjust the surface roughness etc. of the contact surface, The sintered surface 6aa of the sintered body 6a is ground or polished (hereinafter simply referred to as "polishing").

FIG. 3(b) is a cross-sectional view of the sintered body after polishing (hereinafter referred to as "post-polishing sintered body 6b"). As shown in FIG. 3(b), a polished sintered body 6b having a predetermined flatness, surface roughness and thickness is obtained by polishing. For polishing, for example, loose abrasive grains such as GC (green carbide) #800 and GC #3000, loose diamond grains (3 μm), and the like are used. GC#800 loose abrasive grains are combined with an iron surface plate, GC#3000 free abrasive grains are combined with a resin pad, and diamond free abrasive grains are combined with a copper surface plate for polishing. By using loose abrasive grains of GC # 3000 during finishing, it is possible to cause so-called sagging in the sintered powder as the metal part near the surface, and maintain the porosity of the surface relatively high. can do. On the other hand, when diamond abrasive grains are used for finishing, the sharpness is better than when GC # 3000 is used, so sagging does not occur, and as a result, the porosity of the surface is reduced, but the surface is smooth. is obtained. In addition, it is desirable to finish the surface with either GC#3000 free abrasive grains or diamond abrasive grains so that the flatness is 10 μm or less and the surface roughness is Ra 0.05 or less. Further, whether the finishing is performed with GC#3000 or with diamond abrasive grains may be determined from the viewpoint of cost and specifications.

As a resin to be impregnated into the pores of the sintered body 6b after polishing, a two-liquid curable liquid adhesive is prepared. The adhesive preferably contains a fluorescent dye so that the degree of impregnation can be easily observed. In addition, as the adhesive, an adhesive whose main component is a liquid epoxy resin can be used as a main component, and an adhesive whose main component is an amine can be used as a curing agent. In addition, in order to enhance the holding force effect of the vibration type actuator 1, it is desirable that the adhesive contains (disperses) SiC abrasive grains (GC abrasive grains) with extremely high purity and hardness as hard particles. .

Next, an epoxy resin (not shown), which is a liquid adhesive, is applied by a dispenser (not shown) to the polished surface 6ab of the sintered body 6b after polishing, which serves as a sliding surface for the vibrating body 2 . Note that the upper and lower surfaces in FIG. 3(b) are the polished surfaces of the sintered body 6b after polishing. shall point to

After applying an epoxy resin (not shown), the polished sintered body 6b is placed on a hot plate heated to, for example, about 80° C. so that the surface opposite to the surface coated with the epoxy resin (polished surface 6ab) is placed. It is placed in contact with a hot plate for a certain period of time. As a result, the viscosity of the epoxy resin is lowered by heat conduction through the polished sintered body 6b, and the permeation of the epoxy resin into the pores is promoted. A hot plate is a device that heats a plate using an electric heater as a heat source.

After that, the polished sintered body 6b on the hot plate is placed in an oven set at, for example, about 80° C. and left for a predetermined time to cure the epoxy resin. An oven is a device that heats an object to be heated in a closed space, and in a steady state, the ambient temperature inside the oven and the temperature of the object to be heated are the same. Heat treatment in an oven is not necessarily required when the epoxy resin has the property of curing even at room temperature. The duration of the oven heat treatment is determined by the temperature setting of the oven and the curing properties of the epoxy resin. In other words, the temperature and time set for the impregnation treatment using the hot plate and the curing treatment using the oven of the epoxy resin are set according to the curing characteristics of the epoxy resin. need not be the same.

The impregnation and curing treatment of the epoxy resin are not limited to the above methods. For example, after the epoxy resin is applied, the applied epoxy resin is covered with a sheet or film made of a difficult-to-adhere material such as polypropylene, fluororesin, or polyethylene, or rubber, and the epoxy resin is polished from above, and then the sintered body 6b is coated. Apply uniform pressure. The sintered body 6b can be impregnated with the applied epoxy resin and hardened by placing the sintered body 6b in this state directly in an oven without heating with a hot plate. By using such a method, the resin can remain in the pores of the surface layer of the sintered body 6b after polishing due to the surface tension, and the thickness of the resin coating, which will be described later, can be easily adjusted. Become.

FIG. 3(c) is a cross-sectional view schematically showing a state in which resin-impregnated portions 7c are formed by impregnating the pores of the polished sintered body 6b with epoxy resin. By heat-treating the polished sintered body 6b in which the epoxy resin is applied to the polished surface 6ab as described above, the epoxy resin permeates to a depth of a certain distance from the polished surface 6ab, and the resin-impregnated portion 7c is formed. is formed.

The epoxy resin that has not penetrated into the pores remains on the polishing surface 6ab to form a resin film 7b, covering the polishing surface 6ab. That is, in the present embodiment, the step of impregnating the pores of the sintered body 6b after polishing with the epoxy resin is also a film forming step of forming the resin film 7b on the polished surface 6ab. In addition, in FIG. 3C, for convenience of explanation, the thickness of the resin film 7b covering the polishing surface 6ab is exaggerated.

When the polished sintered body 6b having the resin-impregnated portion 7c formed thereon is used as the contact member 6 of the vibration type actuator 1, in order to stabilize the performance, the protruding portion 5 of the vibrating body 2 is aligned with the resin-impregnated portion 7c. Direct contact is required. Therefore, of the resin film 7b that entirely covers the polishing surface 6ab, the portion formed on the region that slides on the contact surface 5a of the protrusion 5 is removed. Such partial removal processing of the resin film 7b can be performed by a so-called aging, which is generally performed before shipment after assembly.

FIG. 3(d) is a cross-sectional view showing a state in which the protrusion 5 of the vibrating body 2 is in contact with the contact body 6 as a product after aging. Due to aging, the contact surface 5a of the protrusion 5 of the vibrating body 2 contacts the second resin-impregnated surface 6f of the surface of the resin-impregnated portion 7c. In addition, the upper portion of the protrusion 5 is in contact with the resin film 7b remaining on the surface of the resin-impregnated portion 7c. is drawn with adjustment. While it is desirable that the amount of resin coating 7b removed in the aging process is small, the resin coating 7b has a thickness The thickness t is desirably 10 μm or less.

As mentioned above, FIG. 3( e ) shows the completed contact 6 . The resin-impregnated portion 7c has a first resin-impregnated surface 6e covered with the resin film 7b and a second resin-impregnated surface 6f not covered with the resin film 7b. The first resin-impregnated surface 6e and the second resin-impregnated surface 6f are substantially coplanar. That is, the polished surface 6ab serves as the first resin-impregnated surface 6e and the second resin-impregnated surface 6f. The second resin-impregnated surface 6f is a friction sliding surface with respect to the vibrating body 2 (projections 5).

When the protrusion 5 (vibrating body 2) and the contact body 6 move relative to each other in the state shown in FIG. occur. Wear powder tends to be discharged to both sides (right and left in FIG. 3(e)) of the second resin-impregnated surface 6f, which is a friction sliding surface. However, since the resin coating 7b is formed on the first resin-impregnated surface 6e, and the upper portion of the protrusion 5 is in contact with the resin coating 7b, the abrasion powder is generated by the metal of the sintered compact 6b after polishing. It is difficult to make direct contact with the part. In this way, it is possible to suppress the corrosion of the contact body 6 caused by moisture adhering to the abrasion powder.

The second resin-impregnated surface 6f, which is a frictional sliding surface, is covered with the first resin-impregnated surface, which is not covered with the resin film 7b, because an epoxy resin transfer film and an oxide film are formed by frictional sliding. Corrosion resistance is higher than 6e.

Further, in this embodiment, the epoxy resin that has not completely penetrated the pores remains on the polishing surface 6ab to form the resin film 7b, covering the polishing surface 6ab. However, the resin coating of the present invention is not limited to this, and the resin coating of the present invention includes various forms that make it difficult for abrasion powder to come into direct contact with the metal part of the sintered body after polishing. For example, the resin film of the present invention only needs to cover the metal portion of the first resin-impregnated surface, and it is not necessary to fill the pores of the first resin-impregnated surface with the resin film.

Further, in the present embodiment, the same resin material is used for the resin (first resin) used to form the resin-impregnated portion 7c and the resin (second resin) used to form the resin coating 7b. Thus, the resin-impregnated portion 7c and the resin coating 7b were formed in one step. However, the present invention is not limited to this, and after forming the resin-impregnated portion 7c using the first resin, the resin coating 7b is formed using a second resin having a viscosity lower than that of the first resin. may be equal.

The resin materials (the first resin and the second resin) used to form the resin-impregnated portion 7c and the resin coating 7b are not limited to epoxy resins, and are generally impregnated materials such as acrylic resins and polyester resins. You can choose the resin used as

Furthermore, in the present embodiment, the polished surface 6ab of the polished sintered body 6b is impregnated with epoxy resin to form the resin-impregnated portion 7c, but the resin-impregnated portion 7c may be formed using another method. As another method, for example, by immersing the entire post-polishing sintered body 6b in a liquid resin under a reduced pressure environment, the post-polishing sintered body is not only polished from the polished surface 6ab but also from the entire post-polishing sintered body 6b. The resin-impregnated portion 7c may be formed by impregnating the inside of the resin 6b with resin. In addition, it is also possible to form the resin film 7b on the polishing surface 6ab with the resin used in such a method.

As described above, the contact member 6 has a structure in which a resin-impregnated portion is formed by sintering metal powder and impregnating the pores of the sintered body 6a with a resin in a part of the sintered body 6a. The pores of the sintered body 6a generally have a maximum length of several μm to 100 μm, although they differ depending on the location. In the present embodiment, a method of performing resin impregnation treatment after polishing the sintered body 6a is adopted, and a method of performing polishing after impregnating the sintered body 6a with resin to form a resin-impregnated portion is adopted. do not have. The reason for this will be explained below with reference to FIG.

FIG. 4(a) is a diagram showing the result of measuring the ratio of pores to resin portions of a sintered body used for manufacturing a contact body for each polishing depth. FIG. 4(a) shows the relationship between the polishing depth, the pores, and the resin portion when resin impregnation is performed before polishing and then polishing is performed, unlike the manufacturing method of the present embodiment. The ratio of pores refers to the ratio of pores to the entire polished surface, regardless of whether or not the pores are impregnated with resin. Moreover, the ratio of the resin portion refers to the ratio of the resin portion to the entire polishing surface. For convenience of explanation, when the polishing depth is 0 mm, the polishing surface is entirely covered with a resin film, so each ratio is 100%.

The density of the SUS420J2 sintered body used for measurement and another sintered body of the same lot was 6.3 g/ml as a result of measurement by the Archimedes method. Since the SUS420J2 ingot has a density of 7.75 g/ml, the ratio of pores in the sintered body is about 19%.

The flatness of the sintered body immediately after sintering generally varies in the range of 0 to 100 μm. The flatness of the sintered body in FIG. 4(a) was 42 μm. When polishing is started, the state in which the entire surface is covered with resin changes to the state in which the metal surface forming the sintered body is exposed. In this case, diamond free abrasive grains (3 μm) are used for polishing. As the polishing proceeds, a metal surface appears on the entire polished surface at a polishing depth of about 57 μm. At this point, the ratio of the pores and the ratio of the resin portions are almost the same, that is, almost all the pores are impregnated with the resin.

When the polishing depth is about 70 μm, the ratio of pores is about 13.5%, and the ratio of the resin portion is about 10%. is about 3.5%. At a polishing depth of 85 μm, the ratio of non-impregnated pores was 3.7%, and the ratio of non-impregnated pores to pores was 31%. ratio is 39%. In this way, as the polishing progresses, the ratio of the resin portion to the pores decreases.

In the region where the polishing depth is 75 μm or more, which is indicated by the square frame in FIG. Therefore, conventionally, by polishing up to such a region, variations in performance of each contact body caused by variations in flatness of the sintered body, variations in the amount of grinding, and the like have been reduced.

On the other hand, in the present embodiment, after polishing the sintered body 6a, the polishing surface 6ab is impregnated with a resin, and then polishing is not performed. This makes it possible to impregnate almost all the pores of the polishing surface 6ab with the resin, that is, to increase the proportion of the resin portion on the surface of the resin-impregnated portion. In addition, in the present embodiment, a region with a stable surface porosity is used by performing polishing to a certain depth or more before impregnating with resin. can be made even smaller. As a result, variations in performance between contact bodies can be reduced.

FIG. 4(b) is an optical microscope photograph of the surface of the resin-impregnated portion of the contact body obtained by the conventional method of polishing after resin impregnation. FIG. 4(c) is an optical micrograph of the second resin-impregnated surface 6f of the contact body according to this embodiment. FIG. 4(b) is an image of a photographing range of about 363 μm×272 μm of the polished surface taken at a magnification of 200 times. FIG. 4(c) is an image of a photographing range of about 363 μm×272 μm of the second resin-impregnated surface 6f taken at a magnification of 200 times. Common to FIGS. 4(a) and 4(b), blackish portions are pores, and whiteish portions are metal portions.

Conventionally, diamond abrasive grains are used for finishing in order to prevent a part of the resin portion from not existing on the same surface as the metal portion on the surface (polished surface) due to the resin being scooped out during polishing. Thus, the surface shown in FIG. 4(b) was obtained. On the other hand, in the present embodiment, since polishing is not performed after resin impregnation, it is possible to obtain a friction sliding surface with a higher ratio of resin-impregnated portions by using GC#3000, which can increase the ratio of pores. can. As a result, the holding force can be improved in the vibration type actuator 1 using the contact member 6 according to this embodiment.

Next, an example of equipment to which the vibration type actuator using the contact body according to the present invention is applied will be described. FIG. 5A is a top view showing a schematic configuration of the imaging device 200. FIG. The imaging device 200 includes a camera body 230 on which an imaging device 210 and a power button 220 are mounted. The imaging device 200 also includes a lens group (not shown) and a lens barrel 240 including a vibration actuator. The driving of the lens group is performed by a vibration type actuator which will be described later. The lens barrel 240 is detachable from the camera body 230 as an interchangeable lens.

FIG. 5B is a cross-sectional view of the lens barrel. The lens barrel includes a leaf spring 10, a contact member 11, a vibrating member 12, a manual ring 15, a lens barrel unit main body 16, an output key 17, a pressure ring 18, a holding base 20, a rotor rubber 21 (anti-vibration rubber) and an output A transmission member 22 is provided.

The contact member 11 is a member corresponding to the contact member 6 described above, and the vibrating member 12 is a member corresponding to the vibrating member 2 described above. The contact member 11 and the vibrating member 12 constitute a vibration type actuator. One surface of the contact member 11 perpendicular to the optical axis L is in contact with the protrusion of the vibrating member 12 , and the other surface is in contact with the rotor rubber 21 . The rotor rubber 21 is sandwiched between the contact member 11 and the output transmission member 22 . Although the details will be described later, when the vibration type actuator is driven, the contact member 11, the rotor rubber 21, and the output transmission member 22 rotate about the optical axis L together.

The holding base 20 holds the vibrating body 12 so as not to hinder the vibration excited by the vibrating body 12 . The leaf spring 10 is pressurizing means that presses the vibrating body 12 against the contact body 11 by pressing the holding base 20 holding the vibrating body 12 against the contact body 11 . By sandwiching the leaf spring 10 between the pressure ring 18 and the holding base 20 , the pressure ring 18 compresses the leaf spring 10 to generate a predetermined pressure force, thereby causing the pressure between the vibrating body 12 and the contact body 11 . Appropriate pressure is applied. The pressure ring 18 is engaged with the lens barrel unit main body 16 on the inner peripheral side by a screw or a bayonet structure, and the amount of compression of the leaf spring 10 is adjusted by moving the pressure ring 18 in the optical axis direction. be. The lens barrel has a structure in which members arranged in the optical axis direction from the holding base 20 to the manual ring 15 are sandwiched between the flange 16 a and the pressure ring 18 .

The lens barrel unit main body 16 has a flange 16a projecting outward so as to be orthogonal to the optical axis L, and a manual ring 15 for manual focusing operation is provided on one surface of the flange 16a. The roller ring 19 includes a plurality of roller shafts 13 formed to extend radially outward, and rollers 14 engaged with the respective roller shafts 13 and mounted rotatably around the roller shafts 13. is installed. The output transmission member 22 and the manual ring 15 are stacked in the optical axis direction with the roller 14 interposed therebetween. The output key 17 is installed on the roller ring 19 .

When the elliptical motion described with reference to FIG. 2 is excited in the projection of the vibrating body 12, a frictional driving force is generated in the contact body 11 in contact with the projection, causing the contact body 11, rotor rubber 8, and output transmission. The member 22 rotates around the optical axis L integrally. The roller 14 in contact with the output transmission member 22 rolls on the surface of the manual ring 15 and moves on the circumference around the optical axis L, thereby rotating the roller ring 19 around the optical axis L. . By rotating the roller ring 19, the output key 17 rotates a cam ring or the like (not shown) engaged therewith to perform an autofocus operation or the like.

The drive of the lens by the vibration type actuator 1 is not limited to the drive of the autofocus lens, and can be used for the drive of the zoom lens. The vibration actuator can also be used to drive a lens or an imaging device for correcting image blur, and in this case, a linear drive vibration actuator is preferably used.

FIG. 6 is a perspective view showing a schematic structure of a robot 100 equipped with vibration type actuators. The robot 100 is an example of a horizontal articulated robot, which is a kind of industrial robot, and has an arm 120 , an arm joint section 111 and a hand section 112 . The arm joint part 111 connects the two arms 120 so that the angle at which the two arms 120 intersect can be changed. The hand portion 112 has a grip portion 121 attached to one end of the arm 120 and a hand joint portion 122 connecting the arm 120 and the grip portion 121 .

Motors used for bending the arm joint 111 and gripping the hand 112 are required to have TN characteristics (sagging characteristics indicating the relationship between the load torque and the number of rotations) of high torque at a low rotation speed. Vibration type actuators are believed to be suitable. Therefore, the vibration type actuator 1 is incorporated in the arm joint section 111 to change the angle between the arms 120, and is incorporated in the hand section 112 to rotate the hand joint section 122 by a predetermined angle.

Although the present invention has been described in detail based on its preferred embodiments, the present invention is not limited to these specific embodiments, and various forms without departing from the gist of the present invention can be applied to the present invention. included. For example, in the above-described embodiment, a sintered body is used as the base material of the contact body, but instead of this, a stainless wrought material having holes formed near the surface by blasting or the like may be used. In addition, although the ring-shaped contact body is shown, the contact body according to the present invention is not limited to this, and can also be used as a square bar-shaped contact body mainly used for linear drive type vibration actuators. can.

Reference Signs List 1 vibrating actuator 2 vibrating body 5 protrusion 6 contact body 6a sintered body 6ab polished surface 6b sintered body after polishing 6e first resin-impregnated surface 6f second resin-impregnated surface 7b resin coating 7c resin-impregnated portion 100 robot 200 Imaging device

Claims (15)

A contact body that contacts a vibrating body in a vibration actuator,
The contact body has a metal sintered body that contacts the vibrating body, and has a resin-impregnated portion impregnated with a first resin on at least one surface of the metal sintered body,
The resin-impregnated portion is
a first resin-impregnated surface coated with a second resin;
a second resin-impregnated surface not coated with the second resin;
A contact body, wherein the first resin-impregnated surface and the second resin-impregnated surface are flush with each other. 2. The contact body according to claim 1, wherein the first resin and the second resin are the same resin. 3. The contact body according to claim 1, wherein the second resin-impregnated surface is a friction sliding surface that receives a frictional driving force from the vibrating body. 4. The contactor according to claim 1, wherein the thickness of said second resin film covering said first resin-impregnated surface is 10 [mu]m or less. 5. The contactor according to claim 1, wherein the first resin contains hard particles. The contact body according to any one of claims 1 to 5, wherein the metal sintered body is a sintered body of martensitic stainless steel and has a Vickers hardness of 550HV0.2 or more. a vibrating body that generates vibration;
and a contact body according to any one of claims 1 to 6,
A vibration-type actuator, wherein the vibrating body and the contact body move relative to each other. 3. A contact portion of said vibrating body with respect to said contact body has a portion in which a cross-sectional area in a plane parallel to said friction sliding surface of said contact body increases with increasing distance from said friction sliding surface. 8. The vibration type actuator according to 7. 9. The vibration type actuator according to claim 7, wherein a contact portion of the vibrating body with respect to the contact body is in contact with the second resin film covering the first resin-impregnated surface. . The vibration type actuator according to any one of claims 7 to 9;
and a member driven by the vibration type actuator. A method for manufacturing a contact body that contacts a vibrating body in a vibration type actuator, comprising:
a sintering step of sintering the metal powder to produce a metal sintered body;
A polishing step of polishing the surface of the metal sintered body;
an impregnation step of impregnating the metal sintered body from the polished surface formed by the polishing step with the first resin to form a resin-impregnated portion;
a film forming step of forming a resin film covering the surface of the resin-impregnated portion with a second resin;
and a removing step of bringing the vibrating body into contact with the surface on which the resin coating is formed, and driving the vibrating body to remove a portion of the resin coating that contacts the vibrating body. manufacturing method. 12. The method of manufacturing a contactor according to claim 11, wherein the impregnation step and the film formation step are performed simultaneously with the same resin. 13. The method of manufacturing a contact body according to claim 11, further comprising a hardening step of making the hardness of the metal sintered body 550HV0.2 or more before the polishing step. 14. The method of manufacturing a contactor according to any one of claims 11 to 13, wherein in said polishing step, free abrasive grains of green carbide are used for finishing. A method for manufacturing a vibrating actuator having a vibrating body and a contact body that contacts the vibrating body, comprising:
a sintering step of sintering the metal powder to produce a metal sintered body;
A polishing step of polishing the surface of the metal sintered body;
an impregnation step of impregnating the metal sintered body from the polished surface formed by the polishing step with the first resin to form a resin-impregnated portion;
a film forming step of forming a resin film covering the surface of the resin-impregnated portion with a second resin;
an assembling step of assembling the sintered metal body and the vibrating body such that the resin coating is in contact with the vibrating body;
and a removing step of removing a portion of the resin coating that contacts the vibrating body by driving the vibrating body.

Images