JP6049277B2 - Vibration type driving device - Google Patents

Description

  The present invention relates to a vibration type driving device. In particular, the present invention relates to a vibration type driving device that relatively moves an ultrasonic vibrator and a driven body by combining vibrations of different vibration modes.

There has been proposed a vibration type driving device that generates vibrations of different vibration modes in an ultrasonic vibrator and combines these vibrations to move the ultrasonic vibrator and a driven body relative to each other.
This vibration type driving device is provided with a pressurizing structure for generating a frictional force between the ultrasonic transducer and the driven body. Further, for example, Patent Document 1 proposes a vibration type driving device that uses two ultrasonic vibrators having the same shape in order to increase the generated output.
In the vibration type driving device as disclosed in Patent Document 1, one ultrasonic spring for applying a pressing force to the ultrasonic transducer and the driven body, and two ultrasonic transducers for holding and fixing the ultrasonic transducer Four support springs are provided.
In addition, the spring and the ultrasonic vibrator are surrounded by a substantially box-shaped case component so that these springs can generate elastic force.
A pair of support springs pressurize and support both ends of one ultrasonic transducer in the longitudinal direction, that is, the relative motion direction. Each of the two ultrasonic transducers is similarly pressurized and supported.
With such a configuration, the displacement and backlash of the ultrasonic transducer due to the reaction force generated when the vibration wave driving device generates an output is suppressed.

In addition to the above, as a vibration type driving apparatus using two ultrasonic vibrators, for example, those taking the form shown in FIGS. 15 and 16 are known.
FIG. 15 is a perspective view of a vibration type driving apparatus in a conventional example, and FIG. 16 is an exploded perspective view of the vibration type driving apparatus.
The vibration type driving device 1 includes substantially rod-like driven bodies 20. Since the driven body 20 is in frictional contact with the ultrasonic vibrator, the driven body 20 is formed of a material having excellent wear resistance such as a stainless steel material.
A first transducer unit 3-1 having an ultrasonic transducer is arranged on the −Z side in the drawing with respect to the driven body 20.
The first vibrator unit 3-1 is fixed to the vibrator unit fixing member 24. A second transducer unit 3-2 including an ultrasonic transducer is disposed on the + Z side of the driven body 20 in the drawing. The second vibrator unit 3-2 is fixed to the vibrator unit fixing member 25.
The vibrator unit fixing member 24 is formed with two guide holes 24b formed in a round hole shape in the Z direction in the drawing.
The vibrator unit fixing member 24 is formed with two protrusions 24c combined with an elastic member 27 described later.
Similarly, the vibrator unit fixing member 25 is formed with two guide holes 25b formed in a round hole shape in the Z direction in the drawing. The transducer unit fixing member 25 is formed with two protrusions 25c combined with an elastic member 27 described later.

The vibration type driving device 1 includes a transmission member 16. The transmission member 16 includes a transmission portion 16a that transmits the output generated by the vibration type driving device 1 to the outside, and four transmission pins 16b that extend in the schematic Z direction.
The two transmission pins 16b of the transmission member 16 are fitted into the two guide holes 24b of the vibrator unit fixing member 24 to form a guide mechanism.
Similarly, the transmission pin 16b and the two guide holes 25b of the vibrator unit fixing member 25 are fitted to form a guide mechanism.
By being combined in this way, the vibrator unit fixing members 24 and 25 can move only in the Z direction in the figure with respect to the transmission member 16.
The vibrator units 3-1 and 3-2 are disposed so as to sandwich the driven body 20, and the vibrator units 3-1 and 3-2 are Z with respect to the driven body 20 in the drawing. Relative movement is possible in the direction, that is, the pressing direction of the contact portion.
An elastic force is applied by the two elastic members 27 so that the vibrator unit fixing members 24 and 25 are pulled in the Z direction.
As described above, the above-described guide mechanism can transmit the generated force in the X direction without inhibiting the application of a desired pressing force to the two ultrasonic transducers and the sliding surface of the slider.
However, since the guide mechanism shown here is fitted so that the round bar and the round hole slide, it is inevitable that a gap of about several tens of micrometers in the X direction in the figure is generated.

JP 2001-86777 A ([0013] etc., FIG. 1)

In the case of the support structure of the ultrasonic vibrator in the vibration type driving device disclosed in Patent Document 1, a pressure spring for generating a pressing force between the ultrasonic vibrator and the driven body, and the ultrasonic vibration A total of five spring parts including four support springs for holding and fixing the child are provided.
In addition, the vibration type driving device requires a substantially box-shaped case part.
As described above, the vibration type driving device has a problem that a plurality of parts and a space are required to support and fix the ultrasonic transducer.
In addition, the vibration type driving apparatus described with reference to FIGS. 15 and 16 is effective in terms of the number of parts and downsizing. However, since the rattling caused by the gaps in the guide mechanism described above occurs, high-accuracy positioning is possible. And the response performance cannot be obtained.

  In view of the above problems, an object of the present invention is to provide a vibration type driving device that can be miniaturized without increasing the number of components and that can improve positioning accuracy and response performance.

Vibration type driving device of the present invention, electrical - a vibrator to have a vibration plate which mechanical energy conversion element is joined, - a mechanical energy conversion element, the electric
A vibration type driving device comprising: a friction surface that is in pressure contact with a contact portion of the vibrator; and a driven body that relatively drives the vibrator in a relative movement direction along the friction surface .
A holding member for holding the vibrator;
A guide mechanism for guiding the holding member so as to be movable along a normal direction of the friction surface;
A pressing force along the relative movement direction with the pressing force along the normal direction against the friction surface, and pressurizing means for generating the holding member,
It is characterized by having.

  According to the present invention, it is possible to reduce the size without increasing the number of components, and it is possible to realize a vibration type driving device that can improve positioning accuracy and response performance.

The perspective view which shows the structural example of the vibration type drive device in Embodiment 1 of this invention. The top view which shows the structural example of the vibration type drive device in Embodiment 1 of this invention. 1 is an exploded perspective view showing a configuration example of a vibration type driving device in Embodiment 1 of the present invention. Sectional drawing which shows the structural example of the vibration type drive device in Embodiment 1 of this invention. The perspective view of the drive mechanism using the vibration type drive device in Embodiment 1 of this invention. The perspective view of the ultrasonic transducer | vibrator in Embodiment 1 of this invention. The figure showing the vibration mode of the ultrasonic transducer | vibrator in Embodiment 1 of this invention. FIG. 3 is a perspective view showing a vibrator unit according to the first embodiment of the present invention. The perspective view which shows the other form of the vibration type drive device in Embodiment 1 of this invention. The disassembled perspective view which shows the structural example of the vibration type drive device in Embodiment 2 of this invention. The perspective view which shows the structural example of the vibration type drive device in Embodiment 2 of this invention. The perspective view which shows the structural example of the vibration type drive device in Embodiment 3 of this invention. The disassembled perspective view which shows the structural example of the vibration type drive device in Embodiment 3 of this invention. Sectional drawing which shows the structural example of the vibration type drive device in Embodiment 3 of this invention. The perspective view which shows the structure of the vibration type drive device in a prior art example. The disassembled perspective view which shows the structure of the vibration type drive device in a prior art example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(Embodiment 1)
As a first embodiment, a configuration example of a vibration type driving device will be described with reference to FIG.
First, the outline | summary of the vibration type drive device in this embodiment is demonstrated.
As shown in FIG. 1, the vibration type driving apparatus 1 includes a driven body 20 having a substantially square bar shape.
Since the driven body 20 is in frictional contact with the ultrasonic vibrator 2, it is formed of a material having excellent wear resistance such as a stainless steel material.
The first vibrator unit 3-1 is arranged on the −Z side in the drawing with respect to the driven body 20. The direction of the transducer unit 3-1 is determined so that a projection 11 b of the ultrasonic transducer 2 described later comes into contact with the driven body 20.
The first vibrator unit 3-1 is fixed to a vibrator unit fixing member (first holding member) 14.
Further, the second vibrator unit 3-2 is arranged on the + Z side of the driven body 20 in the drawing. The orientation of the transducer unit 3-2 is determined so that a projection of the ultrasonic transducer 2 described later comes into contact with the driven body 20.
The second vibrator unit 3-2 is fixed to the vibrator unit fixing member (second holding member) 15.

The vibration type driving device 1 includes a transmission member 16.
The transmission member 16 holds the vibrator unit fixing members 14 and 15 and transmits the output generated by the vibration type driving device 1 to the outside.
Furthermore, two elastic members (pressurizing means) 17 held by the vibrator unit fixing members 14 and 15 are arranged.
In the present embodiment, a coil spring is used as the elastic member 17. Since the generated force can be obtained with respect to the size if it is a coil spring, it is easy to achieve downsizing of the vibration type driving device 1 as a result.
However, other forms such as a leaf spring may be used as the elastic member 17.

Next, the configuration of the ultrasonic transducer 2 according to Embodiment 1 of the present invention will be further described.
FIG. 6 is a perspective view of the ultrasonic transducer 2 used in the first embodiment.
The ultrasonic vibrator 2 is formed by bonding a vibration plate 11 formed in a substantially plate shape with a metal material and a piezoelectric element plate 12 formed in a substantially rectangular shape with a piezoelectric element material which is an electro-mechanical energy conversion element. It is formed integrally.
The ultrasonic transducer 2 is provided with a flexible substrate (not shown) for electrical connection between the piezoelectric element plate 12 and the outside.
The diaphragm 11 includes a rectangular vibrating portion 11a located substantially at the center, protrusions 11b formed at two positions in the X direction on the upper surface of the vibrating portion 11a, and fixed portions formed on both sides in the X direction of the vibrating portion 11a. 11c.
The diaphragm 11 has a substantially symmetrical shape in the X direction and the Y direction. The upper ends of the two protrusions 11b are places where they come into pressure contact with a friction surface of a driven body (not shown).

The two vibration modes excited by the ultrasonic transducer 2 described above will be described with reference to FIG.
In this embodiment, an AC voltage is applied to the piezoelectric element plate 12 to excite the ultrasonic transducer 2 in two out-of-plane bending vibration modes (MODE-A and MODE-B).
MODE-A is a temporary out-of-plane bending vibration mode in which two nodes appear approximately parallel to the X direction in the figure, which is the longitudinal direction of the ultrasonic transducer 2, and has a shape that is substantially symmetrical with respect to the YZ plane.
Due to the vibration of MODE-A, the two protrusions 11b are excited with an amplitude that is displaced in a direction perpendicular to the surface in contact with the driven body (Z direction). MODE-B is a supported out-of-plane bending vibration mode in which three nodes appear substantially parallel to the Y direction in the drawing of the ultrasonic transducer 2 and has a shape that is inversely symmetric with respect to the YZ plane and substantially symmetric with respect to the XZ plane.
The amplitude of displacement in the direction parallel to the surface in contact with the driven body (X direction) is excited by the vibration of MODE-B.
By combining these two vibration modes, an elliptical motion component in a substantially XZ plane is generated on the upper surface of the two protrusions 11b that are contact portions, and a force for driving the driven body in a substantially X direction is generated.
The ultrasonic transducer 2 and the driven body are relatively moved in the substantially X direction by the driving force by the elliptical motion that can be generated in this way.

FIG. 8 is a perspective view of the transducer unit 3 using the ultrasonic transducer 2.
The vibrator unit 3 is formed of the ultrasonic vibrator 2 described with reference to FIG. 6 and the like, and the vibrator holding member 13.
The vibrator holding member 13 is formed with a base portion 13a formed in a substantially plate shape and two vibrator fixing portions 13b protruding on one surface.
The vibrator fixing portion 13b is joined to the fixing portion 11c of the ultrasonic vibrator 2 by means such as adhesion or welding.

Returning to FIG. 1, the vibration type driving device 1 in the present embodiment will be described in more detail.
FIG. 3 is an exploded perspective view of the vibration type driving device of the present embodiment shown in FIG. 2 as seen from the Y direction.
The vibration type driving apparatus 1 will be described with reference to FIGS.
The vibrator unit fixing member 14 is formed with two guide holes 14b formed in a round hole shape in the Z direction in the drawing.
The transducer unit fixing member 14 is formed with two protrusions 14 c that are combined with the elastic member 17.
Similarly, the vibrator unit fixing member 15 is formed with two guide holes 15b formed in a round hole shape toward the Z direction in the schematic drawing.
The transducer unit fixing member 15 is formed with two protrusions 15 c that are combined with the elastic member 17.

The transmission member 16 includes a transmission portion 16a that transmits the output generated by the vibration type driving device 1 to the outside, and four transmission pins (substantially cylindrical members) 16b that extend in the Z direction in the drawing.
Two transmission pins 16b of the transmission member 16 are fitted into two guide holes (substantially cylindrical holes) 14b of the vibrator unit fixing member 14 to form a guide mechanism.
Similarly, the transmission pin 16b and the two guide holes 15b of the vibrator unit fixing member 15 are fitted to form a guide mechanism.
By being combined in this way, the vibrator unit fixing members 14 and 15 can move only in the Z direction in the figure with respect to the transmission member 16.
The vibrator units 3-1 and 3-2 are disposed so as to sandwich the driven body 20, and the vibrator units 3-1 and 3-2 are Z with respect to the driven body 20 in the drawing. It is possible to move relative to the direction, that is, the pressing direction of the contact portion.
For this reason, as will be described later, when a pressing force is applied, the force acts as a pressing force.
However, since the guide mechanism shown here is fitted so that the round bar and the round hole slide, it is inevitable that a gap of about several tens of micrometers in the X direction in the figure is generated.
The guide mechanism is not limited to the configuration described here, and a configuration in which the two vibrator unit fixing members 14 and 15 are guided in the X direction may be selected.
However, the same gap is unavoidable in a position regulating mechanism with general slip.
Two elastic members 17 are arranged so as to connect the two protrusions 14 c of the vibrator unit fixing member 14 and the two protrusions 15 c of the vibrator unit fixing member 15.
The two vibrator unit fixing members 14 and 15 are pulled by the elastic force generated by the elastic member 17, thereby generating a pressing force on the driven body 20 and the protrusions 11 b of the two ultrasonic vibrators 2.

As shown in FIG. 2, the two elastic members 17 are arranged so as to have an angle in the XZ plane with respect to the Z direction, and the elastic members 17 generate a tensile force in the X direction.
FIG. 4 schematically shows a cross section of the vibration type driving device in the XZ plane including the transmission pin 16 b of the transmission member 16.
The two elastic members 17 cause the vibrator unit fixing member 14 to receive a force in the + X direction as well as a force in the + Z direction.
The force in the + X direction acts on the contact surface between the two guide holes 14b and the transmission pin 16b, and the transducer unit fixing member 14 is restricted in the + X direction with respect to the transmission member 16.
Similarly, the vibrator unit fixing member 15 receives the force in the −X direction together with the force in the −Z direction by the two elastic members 17.
The force in the −X direction acts on the contact surface between the two guide holes 15b and the transmission pin 16b, and the transducer unit fixing member 15 is restricted in the −X direction with respect to the transmission member 16.
In this way, the elastic member (pressurizing means) 17 generates an elastic force in the Z direction (normal direction), thereby applying a pressing force to the friction surface of the driven body with the contact portion of the vibrator and the guide. A pressing force in the X direction (relative movement direction) can be generated with respect to the mechanism.
As a result, it is possible to suppress the play due to the gaps inherent in the guide mechanism, and to directly transmit the driving force of the two vibrator units 3 to the transmission member 16, and the vibration type with high precision positioning and high responsiveness. The drive device 1 can be realized.
Further, the vibration type driving device 1 of the present embodiment can obtain a high output by combining the generated forces of the two ultrasonic transducers 2.

FIG. 5 shows a drive mechanism 4 using the vibration type drive device 1.
The drive mechanism 4 includes a base member 31, two guide holding members 32 and 33, two guide shafts 36 and 37, and an operating unit 35.
The guide holding members 32 and 33 are fixed to the base member 31. The two guide shafts 36 and 37 are fixed to the guide holding members 32 and 33 at both ends. The operating unit 35 is combined with the two guide shafts 36 and 37 and is held so as to be movable in the X direction in the figure. Both ends of the driven body 20 of the vibration type driving device 1 are fixed by guide holding members 32 and 33 and two driven body fixing members 34. The fixed portion 16 a of the transmission member 16 provided in the vibration type driving device 1 is fixed to the operating portion 35.
The operating unit 35 is driven in the X direction in the figure by the relative moving force between the ultrasonic transducer 2 and the driven body.
The present invention is not limited to a vibration type driving device that generates a linear motion. For example, the present invention can also be applied to a vibration type driving device that generates a rotational motion using a driven body 21 that can obtain a rotational motion as shown in FIG.

(Embodiment 2)
As a second embodiment, unlike the first embodiment in which two ultrasonic transducers are used, a configuration example of a vibration type driving apparatus using one ultrasonic transducer will be described with reference to FIGS. 10 and 11. explain.
FIG. 10 is an exploded perspective view of the vibration type driving device in the present embodiment, and FIG. 11 is a perspective view.
As in this embodiment, the present invention can be applied even if only one ultrasonic transducer is used according to the required output.
In the present embodiment, the ultrasonic transducer 1 and the transducer unit 3 are the same as those described in the first embodiment.
The vibrator unit fixing member (first holding member) 14, the transmission member 16, and the driven body 20 are the same as those described in the first embodiment. Therefore, description of these components is omitted.

A guide roller (rolling member) 18 is disposed at a position facing the vibrator unit 3 with the driven body 20 interposed therebetween.
The guide roller 18 is held rotatably by a guide roller holding member (second holding member) 19.
The guide roller holding member 19 is formed with two guide holes 19b formed in a round hole shape in the Z direction in the schematic drawing.
The guide roller holding member 19 is formed with two protrusions 19 c that are combined with the elastic member 17.
The two transmission pins 16b of the transmission member 16 and the two guide holes 19b of the guide roller holding member 19 are fitted to form a guide mechanism.
By being combined in this way, the guide roller 18 and the guide roller holding member 19 can move in the Z direction in the figure with respect to the driven body 20.

Two elastic members 17 are arranged so as to connect the two protrusions 14 c of the vibrator unit fixing member 14 and the two protrusions 19 c of the guide roller holding member 19.
When the vibrator unit fixing member 14 and the guide roller holding member 19 are pulled with each other by the elastic force generated by the elastic member 17, a pressing force is generated between the driven body 20 and the protrusion 11 b of the ultrasonic vibrator 2.
As shown in FIG. 2, the two elastic members 17 are arranged so as to have an angle in the XZ plane with respect to the Z direction, and the elastic members 17 generate a tensile force in the X direction.
As in the first embodiment, the force generated by the elastic member 17 is used to generate a pressing force between the ultrasonic vibrator 2 and the driven body 20 and a force that regulates the positional relationship in the X direction in the drawing to the guide mechanism. Can be made.
As a result, since the driving force of the vibrator unit 3 can be directly transmitted to the transmission member 16, the vibration type driving device 1 with high accuracy positioning and high responsiveness can be realized.

(Embodiment 3)
As a third embodiment, a configuration example of a vibration-type driving device having a form different from that of the second embodiment of the vibration-type driving apparatus using one ultrasonic transducer will be described with reference to FIGS.
FIG. 12 is a perspective view of the vibration type driving apparatus 1 in the present embodiment, and FIG. 13 is an exploded perspective view.
In the present embodiment, since the ultrasonic transducer 1, the transducer unit 3, and the driven body 20 are the same as those described in the first and second embodiments, description thereof is omitted.
Further, since the vibrator unit fixing member 15 is the same as that described in the first embodiment, the description thereof is omitted.

The vibration type driving device 1 includes a vibrator unit fixing member 22 that fixes the vibrator unit 3-1.
The vibrator unit fixing member 22 includes a fixing part 22a for fixing the vibrator unit 3-1, a transmission part 22c for transmitting the output generated by the vibration type driving device 1 to the outside, and two transmission pins extending in the Z direction in the drawing. 22b.
Further, two protrusions 22d are provided.
The generated force of the ultrasonic vibrator 2 provided in the vibrator unit 3-1 can be directly transmitted to the outside through the vibrator unit fixing member 22.
The two transmission pins 22b of the vibrator unit fixing member 22 are fitted into the guide holes 15b of the vibrator unit fixing member 15 and are combined so as to be displaceable in the Z direction. Two elastic members 17 are arranged so as to connect the two protrusions 15 c of the vibrator unit fixing member 15 and the two protrusions 22 d of the vibrator unit fixing member 22.
When the two vibrator unit fixing members 15 and 22 are pulled with each other by the elastic force generated by the elastic member 17, a pressing force is generated between the driven body 20 and the protrusions 11 b of the two ultrasonic vibrators 2.
As shown in FIG. 2, the two elastic members 17 are arranged so as to have an angle in the XZ plane with respect to the Z direction, and the elastic members 17 generate a tensile force in the X direction.

FIG. 14 schematically shows a cross section of the vibration type driving device on the XZ plane including the transmission pin 22 b of the vibrator unit fixing member 22.
The two elastic members 17 cause the vibrator unit fixing member 22 to receive a force in the + X direction together with a force in the + Z direction, and the vibrator unit fixing member 15 receives a force in the −X direction together with a force in the −Z direction.
These forces in the X direction act on the contact surface between the two guide holes 15b and the transmission pin 22b, and the vibrator unit fixing member 15 is restricted in the -X direction with respect to the vibrator unit fixing member 22.
As a result, the driving force of the vibrator unit 3-2 is directly transmitted to the vibrator unit fixing member 22.
As described above, since the driving force of the vibrator unit 3-1 is directly transmitted to the vibrator unit fixing member 22, the generated force of the two vibrator units 3- and 3-2 can be directly taken out.
As a result, it is possible to realize the vibration type driving device 1 with high precision positioning and high responsiveness.
According to the configuration of each embodiment of the present invention described above, the backlash caused by the gap inherent in the guide mechanism for holding the ultrasonic transducer and transmitting the output in the vibration type driving device is increased. It becomes possible to suppress without it.
As a result, it is possible to realize a vibration type driving device that is simple and space-saving and that provides excellent positioning accuracy and response performance.

1: Vibration type drive device 2: Ultrasonic vibrator 3: Vibrator unit 4: Drive mechanism 11: Vibration plate 12: Piezoelectric element plate 13: Vibrator holding member 14: Vibrator unit fixing member (first holding member)
15: Vibrator unit fixing member (second holding member)
16: transmission member 17: elastic member 18: guide roller 19: guide roller holding member 20: driven member 21: driven member 22: vibrator unit fixing member

Claims (5)

A vibrator having an electro-mechanical energy conversion element and a diaphragm to which the electro-mechanical energy conversion element is bonded;
A vibration type driving device comprising: a friction surface that is in pressure contact with a contact portion of the vibrator; and a driven body that relatively drives the vibrator in a relative movement direction along the friction surface. A holding member for holding the vibrator;
A guide mechanism that guides the holding member so as to be movable along a normal direction of the friction surface, and a pressing force along the relative movement direction together with a pressing force along the normal direction with respect to the friction surface. Pressurizing means to generate;
A vibration type driving device comprising: The vibration type driving device has a first vibrator and a second vibrator arranged to face each other with the driven body interposed therebetween,
The holding member that holds the two vibrators includes a first holding member that holds the first vibrator and a second holding member that holds the second vibrator.
The first holding member and the second holding member are guided by the guide mechanism so as to be movable in the normal direction of the friction surface,
The pressing means generates an elastic force to apply a pressing force along the normal direction to the friction surface of the driven body with the contact portion of the vibrator, and the relative force to the guide mechanism. 2. The vibration type driving device according to claim 1, wherein a pressing force along the moving direction is generated. The vibrator is constituted by a first vibrator and a rolling member arranged to face each other with the driven body interposed therebetween,
The holding member that holds the vibrator includes a first holding member that holds the first vibrator and a second holding member that holds the rolling member,
The first holding member and the second holding member are guided by the guide mechanism so as to be movable in the normal direction of the friction surface,
The pressing means generates an elastic force to apply a pressing force along the normal direction to the friction surface of the driven body with the contact portion of the vibrator, and the relative force to the guide mechanism. 2. The vibration type driving device according to claim 1, wherein a pressing force along the moving direction is generated.   4. The vibration type driving device according to claim 1, wherein the guide mechanism includes a fit between a substantially cylindrical hole and a substantially columnar member. 5. 5. The vibration type according to claim 1, wherein the pressurizing unit is configured by a coil spring that is inclined with respect to the normal direction and generates a tensile force. 6. Drive device.

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