JP4040172B2 - Vibration wave device and vibration wave drive device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vibration wave device such as a vibration wave motor and a vibration wave drive device having the vibration wave device as a drive source.
[0002]
[Prior art]
Conventionally, as a vibration wave device, for example, a metal elastic body formed in a ring shape or the like bonded with a piezoelectric element as an electro-mechanical energy conversion element is used as a vibration body, and an alternating signal as a drive signal is supplied to the piezoelectric element. A traveling wave type vibration wave motor that utilizes bending vibration excited by the vibration body by applying a vibration, or a rod-shaped vibration wave motor that utilizes bending vibration of a vibration body formed in a rod shape has been put into practical use.
[0003]
As a method of supporting and fixing a vibrating body in a ring-shaped traveling wave type vibration wave motor, a vibrating body is placed on and supported on a felt arranged in a motor case, and the vibrating body is fixed to a fixing portion that fixes the vibrating body to the case. A structure that prevents the propagation of vibration, or the vibrating body itself has a ring shape, and the vibrating body with the fixed part arranged inside is connected with a thin plate (Note that the vibrating body and thin plate are further fixed. In some cases, the structure may be formed integrally), a structure for preventing propagation of vibration to the fixed part, and the like.
[0004]
On the other hand, for the support and fixing of the vibrating body in the rod-shaped vibration wave motor, a structure that prevents the vibration from propagating to the fixed part by connecting the vibrating body and the fixed part using a thin pin (pin) coaxially with the rod-shaped vibrating body is proposed. It had been.
[0005]
[Problems to be solved by the invention]
However, as a method for supporting and fixing the above-described conventional vibrating body, using a felt to support and fix the ring-shaped vibrating body, the felt may be deformed or the vibrating body may be displaced on the felt. Could not be supported and fixed.
[0006]
In addition, in the method using a thin plate or a thin pin, it can be supported and fixed more strongly than a felt, but the vibration energy is transmitted to the fixed part through this plate or pin. It is conceivable that the efficiency of the vibration wave motor is deteriorated, and the vibration leaking to the fixed part is further propagated to the outside to adversely affect peripheral devices.
[0007]
In addition, when a vibrating body is fixed with a thin pin, when a large torque is applied to the vibration wave motor, or when the vibration wave motor outputs a large torque, a large torsional torque is applied to the thin pin and the screw may be broken. is there.
[0008]
However, if the pins are made thicker, more vibrations propagate to the fixed part and the above-described problem becomes even greater.
[0009]
An object of the invention according to the present application is to provide a vibration wave device and a vibration wave drive device that have no vibration propagation to a fixed portion and can firmly fix a vibration body.
[0010]
[Means for Solving the Problems]
The present invention, first electrical between the first elastic body and the second elastic body - mechanical energy conversion element and the second electro - sandwiching the mechanical energy conversion element, the first electrical - mechanical energy A vibration wave having a vibrating body that forms a circular or elliptical motion on surface particles of the first elastic body and the second elastic body by applying an alternating signal to the conversion element and the second electro-mechanical energy conversion element. In the apparatus, the apparatus includes a support member that is disposed between the first electro-mechanical energy conversion element and the second electro-mechanical energy conversion element and is formed of a thin plate member, and the first elastic body. The second elastic body is characterized in that it deforms symmetrically across the support member by applying the alternating signal .
Moreover, the vibration wave drive device of the present invention has the above-described vibration wave device as a drive source.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an embodiment of the present invention.
[0012]
Reference numeral 1 denotes a disk-shaped stator as a vibrating body, a pair of metal elastic plates 2 as elastic bodies having protrusions 5 for amplitude expansion on the outer peripheral portion, and piezoelectric elements 3a and 3b as a pair of electro-mechanical energy conversion elements, It comprises a pair of flexible substrates 6 that electrically connect the piezoelectric elements 3a, 3b and a drive circuit (not shown), a support fixing plate 4, and a hollow bolt 7.
[0013]
Two metal elastic plates 2, two piezoelectric elements 3 a and 3 b, and two flexible substrates 6 are arranged from the outside, and a support fixing plate 4 is arranged on the center plane of the symmetry, and these parts are formed by hollow bolts 7. Is fixed to one piece. The screw holes formed in the central portion of the metal elastic plate 2 are screwed into the screw portions formed on the outer peripheral surface of the hollow bolt 7 so that the piezoelectric elements 3a, 3b, The flexible substrate 6 and the support fixing plate 4 are clamped and fixed.
[0014]
On the other hand, the rotor (not shown) is arranged on one or both sides of the vibrating body 1 and is pressed by a pressing means (not shown) to contact the tip of the amplitude-enlarging protrusion 5 and is driven by a frictional force. .
[0015]
When the piezoelectric elements 3a and 3b are repeatedly deformed in the thickness direction as shown in FIGS. 2 (a) and 2 (b) by the drive alternating signal applied by the drive circuit (not shown), the metal elastic plate 2 generates vibrations that repeat deformation as shown in FIGS. 3 (a) and 3 (b). 2 and 3 are exaggerated in order to facilitate understanding of the state of vibration.
[0016]
Since this vibration is deformed symmetrically in the vertical direction, the support fixing plate 4 arranged on the symmetrical center plane of the vibrating body does not vibrate at all due to the vibration of the metal elastic plate 2 . Therefore, even if the outer peripheral portion of the support fixing plate 4 is supported and fixed to a fixing portion (not shown), the vibration of the vibrating body 1 is not propagated to the fixing portion (not shown). Does not occur at all.
[0017]
Although the support fixing structure of the support fixing plate 4 is not shown, any method such as screw fixing, adhesion, welding or the like may be used.
[0018]
As shown in FIG. 4 (a), the amplitude-enlarging protrusion 5 in the present embodiment is an arch-shaped stainless steel plate formed by press sheet metal, and is arranged side by side on the metal elastic plate 2 and fixed. The fixing method may be any method such as adhesion, brazing, welding, and screwing.
[0019]
Moreover, as the shape of the projection 5 for expanding the vibration, a shape such as the cap shown in FIG. 4B being turned down, an L shape shown in FIG. 4C, a trapezoidal shape shown in FIG. Various shapes may be used.
[0020]
In addition, the wear resistance can be improved by applying or sticking a material having good wear resistance to the tip of the protrusion.
[0021]
FIG. 5 shows the polarization phase and relative phase relationship between the two piezoelectric elements 3a and 3b. When an alternating voltage as an alternating signal whose phase is shifted in time is applied to the piezoelectric elements that are polarized in this manner and are shifted in position, the vibration as shown in FIG. A rotor (not shown) that makes pressure contact with the protrusion 5 of the elastic plate 2 rotates.
[0022]
Here, when the vibrating body 1 is driven by the polarization-treated piezoelectric element shown in FIG. 5, the metal elastic plate 2 deforms and vibrates into a shape having one node diameter as shown in FIG.
[0023]
In addition, when the vibrating body 1 is driven by a piezoelectric element that is polarized as shown in FIG. 6 and is displaced in position, the metal elastic plate 2 has a shape having two node diameters as shown in FIG. 7B. Vibrates and deforms. Also in this case, since the upper and lower metal elastic plates 2 are deformed symmetrically, the support fixing plate 4 does not vibrate at all due to the vibration of the metal elastic plate 2.
[0024]
In the above-described embodiment, the vibrating body 1 is described as the fixed side. However, the protrusion 5 of the vibrating body 1 is brought into contact with the linear rail, and the vibrating body 1 is moved along the rail. You may do it.
[0025]
In the above-described embodiment, the structure in which the support fixing plate 4 protrudes toward the outer diameter side of the vibrating body and the outer diameter portion of the support fixing plate 4 is fixed has been described. The object of the present invention can also be achieved by a structure that protrudes toward the inner diameter side and fixes the inner diameter portion of the support fixing plate 4.
[0026]
Furthermore, as a vibration wave drive device using the vibration wave motor of the above-described embodiment as a drive source, it can be applied to a conventionally used one and provide various devices with high quietness without vibration propagation. Can do.
[0027]
【The invention's effect】
According to the present invention, to vibrate symmetrically vibrator in the thickness direction, since placing the support member in its symmetry center plane, can solve the problem that the vibration propagates in the vibrator to the fixing portion for supporting and fixing the vibration member In addition, it is possible to realize an efficient vibration wave device and vibration wave drive device that can firmly fix the vibration body.
[0028]
In addition, a vibration wave device that can withstand a large torque can be realized.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an embodiment of the present invention.
2A and 2B are diagrams showing deformation of the piezoelectric element of FIG.
FIGS. 3A and 3B are views showing vibration forms of the vibrating body (stator) in FIG. 1;
4A to 4D are perspective views showing examples of protrusion shapes. FIG.
FIGS. 5A and 5B are diagrams showing the polarization polarity and positional phase difference of a piezoelectric element. FIGS.
6A and 6B are diagrams showing the polarization polarity and positional phase difference of a piezoelectric element.
7A and 7B are perspective views showing a deformed shape due to vibration of an elastic body. FIG.
[Explanation of symbols]
1 Vibrating body (stator)
2 Elastic body 3 Piezoelectric element 4 Support fixing plate 5 Protrusion 6 Flexible printed circuit board 7 Bolt

Claims (10)

First electrical between the first elastic body and the second elastic body - mechanical energy conversion element and the second electro - sandwiching the mechanical energy conversion element, the first electrical - said the mechanical energy conversion element In a vibration wave device having a vibrating body that forms a circular or elliptical motion on the surface of the first elastic body and the second elastic body by applying an alternating signal to a second electro-mechanical energy conversion element,
A support member formed between the first electro-mechanical energy conversion element and the second electro-mechanical energy conversion element and formed of a thin plate member ;
The vibration wave device according to claim 1, wherein the first elastic body and the second elastic body are subjected to symmetrical deformation with the support member interposed therebetween by application of the alternating signal . Between the support member and the first electro-mechanical energy conversion element and between the support member and the second electro-mechanical energy conversion element , the first electro-mechanical energy conversion element and the first The vibration wave device according to claim 1 , wherein a flexible printed circuit board that is electrically connected to the two electro-mechanical energy conversion elements is disposed. 3. The vibration wave device according to claim 1, wherein one or both of the first elastic body and the second elastic body is used as a vibration energy output unit. 4. The vibrator vibration wave apparatus according to any one of claims 1 to 3, characterized in that formed in a ring shape. Vibration wave apparatus according to any one of 4 from claim 1, characterized in that the outer peripheral portion of the support member is fixed to the fixing unit. The vibration wave device according to any one of claims 1 to 4 , wherein an inner peripheral portion of the support member is fixed to a fixed portion. The circular or elliptic motion is formed on the surface of the first elastic member and the second elastic body, according to any one of claims 1 to 6, characterized in that in which phase is inverted Vibration wave device. The outer periphery of the support member, the vibration wave apparatus according to claim 5, characterized in that protrudes outward from the first elastic body and the second elastic body. The has a vibrator and a pressure contact with the contact member, the vibrator and the vibration wave apparatus according to any one of claims 1 to 8, characterized in that for relatively moving the said contact body. Vibration wave driving apparatus characterized by having a vibration wave device according to claim 1, any one of 9 as a driving source.

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