JP3147917B2 - Vibrator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration generating element such as a piezoelectric element, and a member, for example, a rotor, which is pressed against a vibrating body by vibrating the vibrating body which receives the vibration from the element. it relates vibration Doko for vibration type motor for relatively moving the vibration member and.

[0002]

2. Description of the Related Art A group of two vibration generating elements such as piezoelectric elements are superimposed to form a group of vibration generating drivers, and two groups are used as a vibration driving source. A metal block as a vibrator is disposed on both sides of the piezoelectric element, a piezoelectric element is disposed between the metal blocks, and an electrode plate for supplying a voltage from an external power supply to the piezoelectric element is interposed between the piezoelectric elements. A vibrator has been proposed in which these metal blocks are fastened together by fastening members such as bolts while sandwiching these piezoelectric elements and electrode plates.

A conventional vibrator will be described with reference to FIG.

[0004] Reference numerals 1 and 2 denote metal blocks before and after forming a vibrating body, reference numerals 3, 4, 5, and 6 denote piezoelectric elements as electro-mechanical energy conversion elements made of PZT or the like, 7, 8, 9, 1, and 1.
Reference numeral 0 denotes an electrode plate, which constitutes a group of vibration generating and driving units (hereinafter referred to as A phase) by the piezoelectric elements 3 and 4, and a group of vibration generating and driving units (hereinafter referred to as B phase) by the piezoelectric elements 5 and 6, respectively. The male screw portion 11a of the fastening bolt 11 inserted from the rear metal block 2 side is
The members constituting these vibrators are integrated by being screwed to a.

[0005] Electrode plate for ground (common ground electrode)
An AC voltage from an A-phase driving AC power supply circuit (not shown) is supplied to the 8 and A-phase electrode plates 7, and a B-phase driving electrode is applied to the ground electrode 10 and the B-phase electrode plate 9. An AC voltage is supplied from an AC power supply circuit (not shown). The ground electrode plate 10 is electrically in contact with the rear metal block 2 having conductivity, and the common ground electrode 8 is connected to the ground-side outputs of the A-phase and B-phase driving AC power supply circuits 13 and 14. The conductive rear metal block 2 is electrically connected to the common ground electrode 8 and the front metal block 1 via the conductive fastening bolt 11.

The vibrator shown in FIG. 3 is used as a vibrator of a pencil-type motor. The vibrator shown in FIG. Rotor 12 in contact with, output member 13 having gear 13a on the outer peripheral portion in contact with rotor 12, output member 13
Sleeve member 16 which is fitted inside bearing 14
The rotor 12 is pressed against the front metal block 1 by a pressure spring 17 elastically mounted between a stopper plate 18 fixed to the distal end of the small diameter shaft portion 15 and the sleeve member 16. .

[0007] Such a pencil-type motor can be miniaturized even smaller than the little finger of a human hand.
The power supply terminal portions 7a to 10a extending radially outward from the power supply terminals 7a to 10a are unbalanced factors in the vibrating system of the vibrator, and have a considerable influence on the vibration. There is a demand to minimize the influence of the department.

Further, since the direction of the power supply terminals 7a to 10a is not particularly specified, it differs for each vibrating body, and is usually determined by a lead wire between power supply circuits. For example, as shown in FIG. 3A, each is arranged at a different position (angle) in the circumferential direction.

However, when these terminal portions 7a to 10a are connected to a power supply circuit by a flexible printed circuit board, the flexible printed circuit board becomes unnecessarily large and complicated due to a large interval between the terminals. There is.

Further, since these terminal portions 7a to 10a do not overlap in the axial direction, when the vibrator is actually arranged, in the example of FIG. It is necessary to provide a maximum of four reliefs, and there is a problem that a space is remarkably wasted when used in a pencil-type motor capable of miniaturization.

[0011]

The problem to be solved by the present invention is that the power supply terminal portion of the electrode plate in contact with the piezoelectric element of the vibrator has an effect on the vibration of the vibrator depending on its arrangement position. It is not suitable for connection to a flexible printed wiring board due to the plurality of terminal portions being located in different directions, and requires extra space around the vibrator.

An object of the present invention is to provide a vibrator capable of minimizing the influence on vibration and minimizing the connection with a flexible printed wiring board and the useless space around it.

[0013]

According to an aspect of the present invention, there is provided an electro-mechanical energy conversion element which generates vibration in response to an electric signal supplied via an interposed power supply member. laminated arrangement, electrical multiple layers - mechanical energy conversion element is a first-phase driving group, stand for the first-phase driving group
And a 90 ° phase different from the first two-phase drive unit, these electric - is integrated in the placement vibration member so as to hold the mechanical energy conversion element and a power supply member, the said first phase driving group In a vibrator that generates vibration such as swinging by combining vibrations excited by the second phase drive group, the power supply member and an external circuit are electrically connected.
And provided outside the power supply member.
The projecting portion for power supply that is output is connected to the first phase drive group and the second phase drive group.
In the position of approximately 45 degree phase, which is in the middle of the phase shift with the drive group
It is characterized by being located .

[0014]

The vibrator having the above-described structure is an electric element such as a piezoelectric element.
Interposed to supply power to the mechanical energy conversion element
The power supply member has a power supply protrusion protruding to the outside thereof,
Approximately 90, which is the phase shift between the one-phase drive group and the second-phase drive group
At a position with a phase shift of about 45 degrees, which is halfway between degrees.
Therefore, the vibration excited by the first phase drive group and the second phase drive
Make the effects on vibrations excited by the motion group approximately equal
Can drive vibration like sway as rigid vibration
An efficient perfect circle can be approached .

[0015]

1 and 2 show an embodiment of a vibrator according to the present invention. The vibrator shown in FIG. 1 is used for a pencil type motor and has the same basic structure as that of the conventional example shown in FIG. 3, so that the same reference numerals are used as those of the components of the motor shown in the conventional example.

The piezoelectric element plates 3 to 6 constituting the vibrator according to the present embodiment have the same structure. For example, in the case of the piezoelectric element plate 3 shown in FIG. Of the piezoelectric element plate 3 has a slit portion 3C where the electrode film is not formed on the diameter line portion, and the electrode films 3A on both sides thereof.
And 3B are formed, and the regions of the electrode films 3A and 3B are polarized in different polarization directions. And the first phase
The driving A-phase piezoelectric elements 3 and 4, which are the driving group, are overlapped, for example, by reversing their polarities (shifting the phase by 180 degrees) so that the central slit portions 3C coincide with each other .
The driving B-phase piezoelectric elements 5 and 6, which are a two-phase driving group, are superposed with the phase shifted by 180 degrees as in the case of the A-phase, but the phase is shifted by 90 degrees with respect to the A-phase. They are staggered. That is, the slit 5C of the piezoelectric element 5 is orthogonal to the slit 3C of the piezoelectric element 3.

On the other hand, a power supply interposed between these piezoelectric elements
The electrode plates 7 to 10 as members are formed as power feeding protrusions.
All of the terminal portions 7a to 10a are aligned in a state of being overlapped in the axial direction.
a is arranged with a phase angle α shifted with respect to the slit 3C of the piezoelectric element 3, and in this embodiment, the phase difference between the driving A-phase piezoelectric element group and the driving B-phase piezoelectric element group is shifted by 90 degrees. The phase angle α is set to 45 degrees because of the arrangement.

That is, in order to vibrate the vibrator only in its length direction, it is not necessary to provide a two-phase piezoelectric element group. Vibrations having different phases are excited by the two-phase piezoelectric element group, and the combined In order to generate vibration such as swinging on the vibrator and frictionally drive the rotor 12 by a circular or elliptical motion formed on the surface of the distal end of the vibrator, a vibration system vibrated by an A-phase driving piezoelectric element group; It is most desirable that the vibration system vibrated by the B-phase driving piezoelectric element group is equivalent.

However, the terminal portion extending from the electrode plate is one.
Therefore, the symmetry of the vibrator is impaired, and in the conventional arrangement as shown in FIG. 3, the axis due to the vibration of the A-phase driving piezoelectric element group and the B-phase driving piezoelectric element group A difference occurs in the mechanical impedance between the directional vibration and the radial vibration,
It becomes impossible to cause the vibrator to perform the swinging motion that draws a substantially perfect circle as described above.

On the other hand, as in the present embodiment, the positions of the electrode plates are conjugate with a phase angle shifted by 45 degrees, which is a position equivalent to the vibration system of the A-phase piezoelectric element group and the vibration system of the B-phase piezoelectric element group. Positioning eliminates differences in mechanical impedance and therefore has no effect on motor performance.

[0021]

As described above, according to the present invention, power is supplied to an electro-mechanical energy conversion element such as a piezoelectric element .
The power supply member installed for
The power projecting portion is out of phase between the first phase drive group and the second phase drive group.
At a position of approximately 45 degrees, which is halfway between approximately 90 degrees.
Therefore, the vibration excited by the first phase drive group and the second phase drive
Make the effects on vibrations excited by the motion group approximately equal
Can be used to drive vibration such as swing as a synthetic vibration.
It is possible to approach a perfect circle with high dynamic efficiency.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a vibrator according to the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a longitudinal sectional view showing a conventional vibrator.

[Explanation of symbols]

 1, 2, metal block 3-6, piezoelectric element plate 7-10, electrode plate 7a-10a, terminal portion 11, bolt 12, rotor 13, output member 14, bearing

Claims (1)

(57) [Claims] 1. An electro-mechanical energy conversion element that generates vibration in response to an electric signal supplied through an interposed power supply member is arranged in a stack, and a plurality of layers of the electro-mechanical energy conversion element are a first layer . The phase drive group and the first phase drive group are approximately
And a 90 ° phase different from the first two-phase drive unit, these electric - is integrated in the placement vibration member so as to hold the mechanical energy conversion element and a power supply member, the said first phase driving group In order to electrically connect the power supply member to an external circuit in a vibrator that generates vibration such as swinging by combining vibrations excited by the second phase drive group ,
Provided outside the power supply member.
The power supply protruding portion, the first phase drive group and the second phase drive
Located at a position of approximately 45 degrees phase, which is halfway between the group and
Vibrator, characterized in that is.