JPS6113072A - Actuator - Google Patents

Abstract

PURPOSE:To permit the control with high accuracy by forming at least a part of the horizontal part and the vertical part of a plurality of displacement members planted in matrix form onto the body part, from piezoelectric element units. CONSTITUTION:A plurality of displacement members 12 are planted in matrix form onto the surface of a body part 10. In said displacement member 12, a pair of vertical parts 14 and 20 are formed, having a horizontal part 18 interposed, and the first and the second piezoelectric element units 22a and 22b are installed onto a part of the horizontal part 18 and the other vertical part 20. When signals are supplied from a control circuit alternately for each displacement member group which shifts in the X direction or Y direction, among the displacement members 12 planted onto the body part 10, the body part 10 shifts freely in the direction of X-Y with respect to a floor surface 26.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an actuator, and more particularly to an actuator that moves or drives an object by effectively utilizing the displacement force of a piezoelectric element.

BACKGROUND ART Moving means that utilize fluid pressure, such as hydraulic pressure or pneumatic pressure, have conventionally been used to transport objects in various machines. This type of moving means can be said to be indispensable for conveyance systems because it generates relatively large forces and strokes. On the other hand, this type of moving means has hitherto encountered a problem in that highly accurate control is difficult because it utilizes fluid.

However, in recent years, piezoelectric elements (piezo) have been attracting attention. In other words, the displacement force of a piezoelectric element is obtained by the distortion that occurs when an electric field is applied to a certain type of crystal or sintered body, and therefore, if this displacement force is used to move or drive an object, Since the control is electrical rather than mechanical, positioning and the like can be reliably performed with high accuracy.

Therefore, the present invention includes the invention of composite piezoelectric ceramics, etc.
The present invention was developed in light of the remarkable performance improvement of piezoelectric elements in recent years, and the object is to provide a novel actuator that moves or drives an object by effectively utilizing the displacement force of the piezoelectric element.

In order to achieve the above object, in the present invention, a plurality of bent rod-shaped displacement members are implanted in a matrix in the main body, and at least a portion of the horizontal and vertical portions of the displacement members are formed by piezoelectric element units. However, it is characterized in that these displacement members are configured to be displaced in conjunction with each other.

Hereinafter, preferred embodiments of the actuator according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a first embodiment of an actuator according to the present invention.

As shown in the figure, a plurality of bent rod-shaped displacement members 12 that are displaced like inchworms are implanted in a matrix on the surface of the main body 10 via piezoelectric element units to be described later.

In this embodiment, the displacement members 12 are disposed so that the displacement members 12 located in odd-numbered rows and even-numbered rows as counted in the direction of the arrow in the figure are displaced in different directions in the X-Y direction. . In this case, as shown in FIG. 2, the displacement member 12 is formed into a round bar shape and is bent in the middle, that is, a pair of vertical parts 14 and 20 are formed with a horizontal part 18 in between, and One vertical part 1
4 has a mounting hole 16 formed on one side of the main body 1o.
It is fixed with a press fit cap as appropriate. Further, the displacement member 1
The second horizontal part 1 and the other vertical part 20 have first and second piezoelectric element units 22a and 22 in their parts, respectively.
Contains b.

The first and second piezoelectric element units 22a and 22b are formed into a round rod shape of a predetermined length by laminating a large number of disc-shaped piezoelectric ceramics, and are connected to a DC power source (not shown) via power wires 24a and 24b. Connect each. Note that in this embodiment, the power lines 24a and 2 from each displacement member 12
4b is connected to a control circuit (not shown), and each displacement member 12 is configured to be displaced in conjunction with a signal from the control circuit. Further, the first and second piezoelectric element units 22a and 22b are connected to the power supply lines 24a and 24, respectively.
It will be easily understood that when a voltage with a predetermined polarity is applied through b, the displacement member 12 is expanded and displaced in the axial direction.

The actuator according to the present invention is basically constructed as described above, and its operation and effects will be explained next.

Now, for each group of displacement members displacing in the X direction and the Y direction among the displacement members 12 implanted in the main body 10, a control circuit (not shown) performs a displacement operation in which one cycle includes the four operations shown in FIG. 4, the main body 10 can freely move in the X-Y direction with respect to the floor 26, as shown in FIG.

To explain this in more detail with reference to FIGS. 3A to 3D, first, the power supply line 22b is
A predetermined voltage is applied via 4b. As a result, the second piezoelectric element Unisol l-22b of the vertical section 20 is elongated and displaced, and the tip surface 20a of the vertical section 20 comes into contact with the floor surface 26 and is strongly pressed against it, as shown in FIG. 3A. . At this time, in each displacement member 12 of the other displacement member group, since no voltage is applied to the second piezoelectric element UNISOL 1-22b, the vertical portion 20 does not extend and displace. is slightly lifted from the floor surface 26.

Next, while maintaining the above state, a predetermined voltage is applied to the first piezoelectric element Unisol 1-22a in the horizontal portion 18 via the power supply line 24a. As a result, the first portion of the horizontal portion 18
The piezoelectric element unit 22a is in the state shown in FIG. 3B,
Elongation displacement in the horizontal direction. At this time, the tip surface 20a of the vertical portion 20 is strongly pressed against the floor surface 26, and the tip surface 20a,
Since it remains fixed due to the frictional resistance between the floor surfaces 26, the main body 10 eventually moves horizontally in the direction of the arrow in the figure as the horizontal portion expands during the day.

After this, the second piezoelectric element 22 of the vertical portion 20
The application of voltage to b is stopped, and the piezoelectric element
22 b is contracted and displaced. Note that at this time, in each displacement member 12 of the other displacement member group, the second piezoelectric element
When a voltage is applied to 22b, the piezoelectric element 22b
is elongated and displaced. As a result, the main body 10 is now supported by the other displacement member group, and each displacement member 12 of one displacement member group is in a state slightly floating above the floor surface 2G (the state shown in FIG. 3C). reference).

And finally, the first piezoelectric element Unison of the horizontal part 18)
The application of voltage to 22a is stopped.

As a result, the piezoelectric element 22a is contracted and displaced, and eventually each displacement member 12 of one displacement member group returns to the state shown in FIG. 2 (see the state shown in the third diagram). Of course, after this, the application of voltage to the second piezoelectric element unit 22b of each displacement member 12 in the other displacement member group is also stopped, and the main body portion IO is supported by both displacement member groups.

In this way, each displacement member 12 of one displacement member group is adjusted to the vertical displacement (extension displacement) in the second piezoelectric element unit l-22b - the horizontal displacement (extension displacement) in the first piezoelectric element unit 22a - the second piezoelectric element unit 1-22b. If the vertical displacement (shrinkage displacement) in the element unit 22b and the horizontal displacement (shrinkage displacement) in the first piezoelectric element unit 22a are repeated as one cycle, the main body 10 will sequentially move in the X direction or the Y direction. do. In other words, each displacement member 1
2 moves the main body 10 linearly by a predetermined stroke by a displacement movement like a so-called inchworm. Therefore, by alternately displacing the displacing member group displacing in the X direction and the displacing member group displacing in the Y direction, the main body 10 can freely move in the X-Y direction, as shown in FIG. .

On the other hand, when performing a movement in the opposite direction to the movement illustrated in FIG. 4, each displacement member 12 of each displacement member group
is the horizontal displacement (
elongation displacement) - vertical displacement (elongation displacement) in the second piezoelectric element unit 22b - first piezoelectric element unit 22a
It is easily understood that it is sufficient to repeat the displacement (horizontal displacement (contraction displacement) in the second piezoelectric element 22b - vertical displacement (contraction displacement) in the second piezoelectric element 22b) as one cycle.

Next, FIGS. 5 to 8 show second to fifth embodiments of the actuator according to the present invention.

FIG. 5 shows the vertical portion 20 of the actuator shown in FIG.
An embodiment is shown in which an elastic body 30 made of rubber or the like is disposed on the distal end surface 20a. In this case, the elastic body 30 increases the frictional resistance during crimping with the floor surface 26, etc.
Movement control is precisely achieved.

FIG. 6 shows an embodiment in which the main body part 10 in FIG. 4 is formed into a curved shape so that it can move freely in the X-Y direction on a floor surface 26 which is also formed into a curved shape.

FIG. 7 shows that the main body 10 in FIG. 4 is formed into a cylindrical shape and is fixed, and a shaft 32 having a circular cross section is inserted into the body, and a displacement member 12 that moves in the X-Y direction is used. An embodiment in which the shaft 32 is moved or rotated in the axial direction is shown.

FIG. 8 shows an embodiment in which the main body portions 10 in FIG. 7 are combined in multiple stages to form a cylindrical member that is entirely rotatable and expandable.

As explained above, according to the present invention, a plurality of bent rod-shaped displacement members are implanted in a matrix shape in the main body, and at least a portion of the horizontal and vertical portions of the displacement members are connected to the piezoelectric element unit 2. Since the piezoelectric element is formed with a piezoelectric element, and these displacement members are displaced in conjunction with each other, an object can be easily moved or driven in any direction by effectively utilizing the displacement force of the piezoelectric element. is obtained. In this case, since the displacement control is performed electrically, it is also effective in that it is performed with extremely high precision.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to the above embodiments, and various improvements and changes in design are possible without departing from the gist of the present invention. Of course.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a first embodiment of the actuator according to the present invention, FIG. 2M is an enlarged sectional view of the main part of the device shown in FIG. 1,
3A to 3D are sectional views showing the operating order of the displacement members of the device shown in FIG. 1, FIG. 4 is an explanatory diagram showing the operating state of the device shown in FIG. 1, and FIG. FIG. 6 is a cross-sectional view showing a second embodiment of the actuator according to the present invention, FIG. 6 is a front view showing a third embodiment of the actuator according to the present invention, and FIG. FIG. 8 is a front view showing a fifth embodiment of the actuator according to the present invention. 10...Body part 12...Displacement member 14...Vertical part j6...Mounting hole ■8...Horizontal part
20... Vertical parts 22a, 22b... Piezoelectric element units 24a, 24b... Electric wire 26... Floor surface 3o... Elastic body 32... Shaft (c) lUO (d) Uq

Claims (4)

[Claims] (1) A plurality of bent rod-shaped displacement members are implanted in a matrix in the main body, and at least a portion of the horizontal and vertical portions of the displacement members are formed by piezoelectric element units;
An actuator characterized in that these displacement members are configured to displace in conjunction with each other. (2) In the device according to claim 1, the displacement member is configured to perform a displacement operation in the order of vertical displacement→horizontal displacement→vertical displacement→horizontal displacement, or the opposite displacement as one cycle. An actuator that does this. (3) In the device according to claim 1 or 2, the displacement members are arranged in rows divided into a group of displacement members that displace the main body in the X direction and a group of displacement members that displace the main body in the Y direction. An actuator configured to be provided in a shape. (4) In the device according to any one of claims 1 to 3, the displacement member is an actuator in which an elastic body such as rubber is disposed on the distal end surface of the free end.