JPH07280670A - Driving and detecting structure and its controller - Google Patents

Abstract

PURPOSE:To provide a driving and detecting structural body that is of a small structure and can perform detection and fine movement and its controller than can be used in such an applicable manner that is suitable to a device to be used. CONSTITUTION:The driving and detecting structural body 10 consists of a rigid body 11, an expansion body 14, elastic bodies 12a and 12b connecting the both ends of the body 14 and the body 11, and strain gauges 15 provided on the bodies 12a and 12b. The strain gauge 15 on either of the bodies 12a and 12b is used to detect the displacement thereof respectively and the force is detected based on the difference between the detected values that are obtained by the both strain gauges 15. The characteristic of target values of displacement or force is set in a controller, and the body 14 is controlled in such a manner that the detected value will become a target value, so that the body 10 can be made to perform actions corresponding to the characteristic of the target value. Desired action can be realized by selecting the characteristic of target value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive / detection structure for detecting a force acting on an object or an amount of displacement of the object, applying a force to the object or displacing the object, or simultaneously performing them. Regarding the control device.

[0002]

2. Description of the Related Art A means for detecting a force acting on an object or a displacement amount of the object is proposed in, for example, Japanese Patent Laid-Open No. 60-62497. This means is basically composed of a parallel plate structure composed of two rigid body parts and two parallel flat plates connecting these rigid body parts. This is shown in FIG.
Will be described.

FIG. 22 is a side view of the parallel plate structure of the load detector. In (a) of this figure, 1 is a rigid block, 2
Is a through hole formed in the block 1. This through hole 2
The formation of two rigid body portions 1a and 1b, and thin parallel flat plates 3a and 3b that connect the rigid body portions 1a and 1b at both ends are formed. These rigid body portions 1a, 1
b and the flat plates 3a and 3b form a parallel flat plate structure.
Reference numeral 4 is a strain gauge attached to a predetermined position on the surface of each of the parallel plates 3a and 3b, and A is a fixed portion to which one rigid body portion 1a is fixed.

When a force F is applied to such a parallel plate structure as shown in FIG. 1B, the parallel plates 3a and 3b bend as shown in the figure, and the strain gauge 4 detects the amount of the bending. To be done. This detection is performed based on the output of the bridge circuit composed of four strain gauges 4. The deflection of the parallel plate is actually a very small (on the order of μm) deflection, and is exaggerated in the drawing for ease of understanding. The same applies to the following figures.

While the above parallel plate structure detects a force applied from the outside, a device for positively generating a displacement utilizing the parallel plate structure is disclosed in, for example, Japanese Patent Laid-Open No. 61-61.
It is proposed in Japanese Patent Publication No. 209846. This will be described with reference to FIG. FIG. 23 is a side view of the fine positioning device. In (a) of this figure, 5 is a rigid block,
Reference numeral 6 is a through hole formed in the block 5. By forming the through hole 6, the two rigid body portions 5a and 5b and the rigid body portion 5a are formed.
Protrusions 5a ₁ protruding into the through-hole 6 from the protrusion 5b which protrudes into the through hole 6 from the rigid portion 5b _1, and these rigid portions 5a, 5b are parallel to each other thin flat plate 7a which connects at both ends, 7b is It is formed. 8 is a protrusion 5 ₁ and a protrusion 5 b
₁ is a laminated piezoelectric element mounted between opposed surfaces of ₁ . In addition, 4 is the same strain gauge as shown in FIG. 22, and A is a fixed part to which one rigid body part 5a is fixed.

When an appropriate voltage is applied to the piezoelectric element 8,
As shown in (b) of FIG. 23, the piezoelectric element 8 expands and the force f
The protrusion 5b ₁ is pushed with, and thereby the rigid body 5b is displaced. This amount of displacement is indicated by δ in the figure. The displacement amount δ is detected by a bridge circuit composed of each strain gauge 4 as in the case of the detecting device having the parallel plate structure. The displacement amount δ is a displacement amount of the order of μm or sub μm, and such a fine positioning device (fine movement mechanism) is used in the fields of ultra-precision processing devices, semiconductor manufacturing devices, optical disk manufacturing devices, and the like.

[0007]

As described above, conventionally, the detection device and the fine movement mechanism have been separately proposed. By the way, in recent years, devices that require both detection and fine movement are used in many fields,
On the other hand, the detection device and the fine movement mechanism are independently used. For this reason, a space for installing them in each of the detection device and the fine movement mechanism was required, but the place where the detection device and the fine movement mechanism are installed is usually extremely small, and the installation is designed by design. However, there was a problem in that the locations concerned were inevitably increased in size due to the difficulty of installation. Of course, by connecting the rigid body portion 1b shown in FIG. 22 to the rigid body portion 5a shown in FIG. 23, or by connecting the rigid body portion 5a shown in FIG. 23 to the rigid body portion 1a shown in FIG. It is conceivable to integrate the above to form a small size,
Even this is inevitable that it will become large.
In addition, in the former case, since the fine movement device is fixed to the tip of the detection device, there arises a problem that the resonance frequency of the detection device decreases and the force detection frequency band decreases.
In the latter case, the detection device is fixed in front of the fine movement device, and the rigidity of the detection device is low, which causes a problem that the displacement generated in the fine movement device cannot be accurately transmitted.

An object of the present invention is to solve the above-mentioned problems in the prior art, to perform detection and fine movement without affecting each other with a compact structure, and to use a driving mode suitable for a device to be used. It is to provide a detection structure and its control device.

[0009]

In order to achieve the above object, the present invention provides a stretchable body which stretches in a predetermined direction, a non-stretchable body facing the stretchable body, both ends of the stretchable body and the non-stretchable body. It is characterized by comprising an elastic body connecting between the body and a detection means for detecting a relative displacement amount between the both ends of the stretchable body and the non-stretchable body in the predetermined direction.

Further, according to the present invention, a stretchable body which stretches in a predetermined direction, a non-stretchable body facing the stretchable body, an elastic body connecting between both ends of the stretchable body and the non-stretchable body, Each displacement amount detecting means for detecting each relative displacement amount between the both ends of the elastic body and the non-elastic body in a predetermined direction, and both ends of the elastic body based on each detection value of the displacement amount detecting means and the above-mentioned And a force detection unit that detects a force that causes relative displacement with the non-stretchable body.

Further, in addition to the configuration, the present invention further comprises a selection means for selecting one of the detection values, a target value generation means for arbitrarily generating a characteristic of the target value of the selected detection value, and Calculating means for calculating a deviation between the target value generated by the target value generating means and the detection value selected by the selecting means, and an elastic body drive for driving the elastic body according to the deviation obtained by the arithmetic means And means are provided.

[0012]

When a force is applied to one of the stretchable body and the non-stretchable body, the elastic body is bent, and the acting force or the amount of displacement can be detected by detecting the bending by the detecting means. Further, when the elastic body is driven, the elastic body is expanded and contracted while the elastic body is flexed, whereby displacement can be generated in the elastic body or the non-elastic body.

Further, in the drive / detection structure control device, each displacement amount detecting means detects each relative displacement amount between both ends of the stretchable body and the non-stretchable body, and the displacement is detected based on these detected values. Detects quantity and force. Thereby, the force and the displacement amount can be detected individually or simultaneously.

Further, any one of the displacement amount and the force detected by the above means is selectively output by the selecting means, and the target value of the selected displacement amount or force is set to an arbitrary characteristic, According to these characteristics, a target value corresponding to the detected displacement amount or force is output from the target value generating means, the deviation between the output value from the selecting means and the output value from the target generating means is calculated, and this deviation is calculated. The expansion and contraction of the elastic body is controlled accordingly. This enables a usage mode adapted to a device using the drive / detection structure.

[0015]

The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a perspective view of a drive / detection structure according to a first embodiment of the present invention. In this figure, reference numeral 10 shows the drive / detection structure of the present embodiment. The drive / detection structure 10 is composed of a non-stretchable body 11 (hereinafter referred to as a rigid body portion), a rigid body portion 11 and flat plate-like elastic bodies 12a and 12b extending in parallel in the same direction from both ends thereof. Elastic body 12a,
Coupling portions 13a and 13b formed at the other end of 12b, and a stretchable body 1 coupled to these coupling portions 13a and 13b.
It is composed of four. In the case of the present embodiment, a laminated piezoelectric element is used for the elastic body 14. 15 is an elastic body 12
4 shows four strain gauges (displacement detecting means) attached to predetermined positions on the surface of a, and four strain gauges same as the strain gauge 15 are also attached to symmetrical portions on the elastic body 12b. As described above, the rigid body portion 11 and the elastic body 12
The a and 12b and the connecting portions 13a and 13b are integrally formed from a rigid block by electrical discharge machining or the like.

FIG. 2 is a modeled view of the drive / detection structure 10 shown in FIG. In this figure, the same parts as those shown in FIG. 1 are designated by the same reference numerals. Reference numerals 11a and 11b denote measuring units attached to detect displacements due to deformation of the elastic bodies 12a and 12b (shown by spring bodies).
The distance between the end surface of the measuring unit 11a and the end surface of the elastic body 14 is y _0.
In addition, the distance between the end surface of the measuring unit 11b and the end surface of the elastic body 14 is z ₀ , and the length of the elastic body 14 in the expansion and contraction direction is x _0.
Each is represented by.

The basic operation of this embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram showing an operation when the rigid body portion 11 is fixed to the fixed portion A. FIG. 3A shows a case where the elastic body 14 is extended in the direction of expansion and contraction with the rigid body portion 11 fixed to the fixed portion A, and this extension is performed while deforming the elastic bodies 12a and 12b. The extension of the elastic body 14 is indicated by x, and the displacement amounts of the joint portions 13a and 13b caused by this extension with respect to the rigid body portion 11 are indicated by y and z, respectively.

FIG. 3B shows a model of this. In the case of this model, when the expandable / contractible body 14 extends by the length x, the respective end surfaces thereof approach the measuring portions 11a and 11b, and the distances between them are (y ₀ −y) and (z, respectively).
_0- z). In this way, by controlling the amount of extension of the elastic body 14 (by controlling the applied voltage in the case of a piezoelectric element), the coupling portions 13a, 13 are connected to the rigid body portion 11.
A desired displacement can be generated in b.

FIG. 3C shows the case where the force component F in the expansion / contraction direction of the elastic body 14 is applied from the outside in the state where the rigid body portion 11 is fixed to the fixed portion A. In this case, the stretchable body 14 acts as a rigid body and operates in the same manner as the conventional parallel plate structure. The displacement amounts of the coupling portions 13a and 13b with respect to the rigid body portion 11 caused by the deformation of the elastic bodies 12a and 12b by the force F are indicated by y and z, respectively.

FIG. 3D shows a model of this. In the case of this model, the force F acts on the stretchable body 14, so that one end face of the elastic body 14 separates from the measuring unit 11a and the other end face thereof approaches the measuring unit 11b. Each interval between the two (y ₀ -y), a (z ₀ -z). These intervals (displacement amount ... Proportional to the force F) are obtained as the output of the bridge circuit based on the strain amount of each strain gauge 15 configured in the bridge circuit.

FIG. 4 is a diagram showing an operation when one end of the expandable body 14 is fixed to the fixed portion A. FIG. 4A shows a case where the elastic body 14 is fixed in the fixing portion A and the elastic body 14 is expanded in the expansion / contraction direction.
It is performed while deforming 12b. The extension of the elastic body 14 is indicated by x, and the connecting portions 13a, 1 generated by this extension
The displacement amounts of 3b with respect to the rigid portion 11 are indicated by y and z, respectively.

FIG. 4B shows a model of this. In the case of this model, when the expandable / contractible body 14 extends by the length x, the respective end surfaces thereof approach the measuring portions 11a and 11b, and the distances between them are (y ₀ −y) and (z, respectively).
_0- z). In this way, by controlling the amount of extension of the elastic body 14 (by controlling the applied voltage in the case of a piezoelectric element), the coupling portions 13a, 13 are connected to the rigid body portion 11.
A desired displacement can be generated in b.

FIG. 4 (c) is a model of the operation shown in FIG. 4 (a) by a model different from that of FIG. 4 (b), and the measuring section 11b is not the rigid body section 11 but the fixed section. It is fixed to the A side and faces the end surface of the rigid body portion 11. In this case, due to the extension of the elastic body 14, the measuring portion 11a and the end surface of the elastic body 14 come close to each other, but the distance between the end surface of the rigid portion 11 and the measuring portion 11b (the distance between the end surface of the rigid portion 11 with respect to the fixed portion A) is As shown in the figure, it is separated from (y ₀ + y).

FIG. 4D shows a case where the force component F in the expansion / contraction direction of the elastic body 14 is applied from the outside while the elastic body 14 is fixed to the fixing portion A. In this case, similarly to the case shown in FIG. 3C, the expansion / contraction body 14 functions as a rigid body and operates in the same manner as the conventional parallel plate structure. Coupling portion 13 caused by deformation of elastic bodies 12a and 12b by force F
The displacement amounts of a and 13b with respect to the rigid body portion 11 are y,
indicated by z.

FIG. 4E is a diagram modeling this. In the case of this model, the force F acts on the stretchable body 14, so that one end face thereof approaches the measuring unit 11a and the other end face thereof separates from the measuring unit 11b. Each interval between the two _{(z 0 -z), (y} 0 -y), and becomes. These intervals (displacement amount ... Proportional to the force F) are obtained as the output of the bridge circuit based on the strain amount of each strain gauge 15 configured in the bridge circuit.

FIG. 4 (f) is a diagram when the same model as in FIG. 4 (c) is used. The force F acts so that the distance between the measuring portion 11a and the end surface of the elastic body 14 and the distance between the end surface of the rigid portion 11 and the measuring portion 11b (the distance between the end surface of the rigid portion 11 and the fixed portion A) are close to each other. To do.

FIG. 5 is a diagram showing a specific example of the stretchable body 14 shown in FIG. These specific examples are shown using the model shown in FIG. The elastic body 14 shown in (a) is a laminated piezoelectric element, electrostrictive element, or magnetostrictive element. The expandable body 14 shown in (b) is an electrostatic actuator in which upper and lower comb-shaped electrodes are alternately opposed to each other. The expandable body 14 shown in (c) is a core 14a, a magnet 14b, and a voice coil 14c.
Is an electromagnetic actuator (voice coil motor). The elastic body 14 shown in (d) is the fluid outflow port 1
It is a fluid actuator composed of a cylinder having 4d and 14e, and a hydraulic cylinder, a pneumatic cylinder or the like is used. The stretchable body 14 shown in (e) is stretched (expanded, by expansion or contraction) by heating or cooling 14 g of a heat member (heating element or cooling body).
It is a thermal actuator composed of a member 14h that contracts. The expandable body 14 shown in (f) is a rotation-to-linear motion converter including a motor 14i, a screw 14j rotated by the motor 14i, and a ball screw 14k. Any of these stretchable bodies 14 is used depending on the object to which the drive / detection structure 10 is applied.

FIG. 6 is a diagram showing a specific example of the displacement detecting means. These specific examples are shown using a model as in the specific example of the stretchable body shown in FIG. The displacement detecting means shown in (a) is a capacitance measuring means which is provided on one of two opposing surfaces where a relative displacement occurs, and which measures the displacement by a change in the capacitance between the other surface. is there. The displacement detecting means shown in (b) is the same strain gauge as that shown in FIG. The displacement detecting means shown in (c) is a piezoelectric element (its rigidity is extremely lower than that of the piezoelectric element used for the expandable body 14) interposed between two opposing surfaces in which displacement relatively occurs. The expansion and contraction due to the displacement of the two surfaces generate a voltage according to the displacement. The displacement detecting means shown in (d) is a laser length measuring device provided on one of the two surfaces facing each other in which displacement relatively occurs, and reaches the other surface by the interference of light with the other surface. Is measured, and the displacement amount is measured based on the measured value. The displacement detecting means shown in (e) is an electromagnetic induction measuring means which is provided on one of two opposing surfaces where a relative displacement occurs and which measures the electromagnetic induction between the other surface and obtains the displacement amount. .

As described above, in this embodiment, since both ends of the rigid body portion 11 and the stretchable body 14 are connected by the elastic bodies 12a and 12b and the displacement detecting means is provided, the operation is simple and small. It is possible to perform both the detection of the force exerted and the driving (fine movement) of the object.

Next, the control of the drive / detection structure 10 will be described. FIG. 7 is a block diagram of a drive / detection structure control device according to an embodiment of the present invention. In this figure, 1
00a is a displacement detector composed of a bridge circuit composed of four strain gauges 15 provided on the elastic body 12a, and 100b is a displacement detection composed of a bridge circuit composed of four strain gauges 15 provided on the elastic body 12b. , 101a, 101b are displacement detectors 100a,
It is a detection signal amplifier circuit for amplifying the output signal of 100b. Reference numeral 102 denotes a level adjusting circuit, which adjusts the output signal of the detection signal amplifying circuit 101b so as to adjust each elastic body 1
Difference in rigidity between 2a and 12b, displacement detectors 100a and 10b
This is a circuit for compensating for the imbalance caused by the difference in sensitivity of. Reference numeral 103 is a calculator that obtains the acting force by calculating the deviation between the output signal of the detection signal amplifier circuit 101a and the output signal of the level adjusting circuit 102. The output signal of the detection signal amplification circuit 101a is used as it is as the signal of the displacement amount D, and the output signal of the calculator 103 is used as the detection signal of the force F.

A selector 104 selects either the detected displacement amount D or the detected force F. 105
Is a target value generating circuit that generates an arbitrary target value, which will be described later. Reference numeral 106 denotes a calculator for calculating the deviation between the output signal (detection signal) of the selector 104 and the output signal (target value signal) of the target value generation circuit 105, and 107 denotes an output for canceling the deviation calculated by the calculator 106. A servo circuit 108 is generated and is an expander / contractor drive circuit for expanding / contracting the expandable / contractible body 14 according to a signal from the servo circuit 107.

Now, the operation of the control device shown in FIG. 7 will be described. Displacement detectors 100a, 10 in this control device
0b, the detection signal amplification circuits 101a and 101b, the level adjustment circuit 102, and the calculator 103 can obviously detect the displacement amount D and the force F by the drive / detection structure 10. However, the drive / detection structure 10 can not only simply detect the displacement amount D and the force F and finely move by the telescopic body 14, but also by setting a target value in the target value generation circuit 105, The special actions described can be performed.

FIG. 8 is a characteristic diagram when the displacement amount D is selected by the selector 104 and the displacement amount D is controlled by the detected force F. 8 (a), (b), (c), (d)
In both figures, the force F is plotted on the horizontal axis and the displacement D is plotted on the vertical axis. These characteristics can be obtained, for example, by storing them in the function generator or the storage unit of the microcomputer. The characteristic C ₁ shown in (a) is a characteristic that holds the displacement at a substantially constant value 0 even if the force changes. This characteristic is set (or selected) by the target value generation circuit 105, and the displacement amount D detected by the selector 104 is selected. In this state, no matter what magnitude of force F is detected and input, signal 0 is output from target value generation circuit 105. Therefore, the expander 14 is driven by the computing unit 106, the servo circuit 107, and the extender drive circuit 108 so that the detection value of the displacement detector 100a becomes zero. That is, no matter what force F acts on the drive / detection structure 10, the stretchable body 14 is driven and the elastic body 12a is maintained in a state of being hardly deformed.

FIG. 9 is a diagram showing this state. In this figure, the same or equivalent parts as those shown in FIG. 1 are designated by the same reference numerals. An external force F is applied to the drive / detection structure 10.
Is working, but the control unit shown in FIG.
4 is stretched so as to generate a force against the force F. As a result, the displacement of the joint portion 13a with respect to the rigid body 11 does not occur, but the displacement of the joint portion 13b occurs, and the force F is detected here.

By the way, since the force detector is generally interposed in the force transmission path, the elastic body (soft portion) of the force detector is interposed in the force transmission path. Therefore, strictly speaking, the detected value of the force detector cannot be said to detect the true value of the force, and a problem arises in a device requiring extremely high precision. However, if the drive / detection structure 10 is controlled to the state shown in FIG. 8, the elastic body 12a is not deformed, so that the rigidity is apparently increased, and the (soft portion) does not intervene in the force transmission path, which is ideal. Force detector can be obtained.

Further, the characteristic C ₁ can be used for cutting, for example. In the cutting process, if a conventional force sensor is inserted to measure the cutting force applied to the tool, the rigidity of the force sensor is low and the supporting rigidity of the tool is reduced. Therefore, there is a problem that elastic deformation occurs due to the force received from the work material during cutting, the tool retracts, and the processing accuracy decreases. However, by applying the drive / detection structure 10 to the holder support and setting the characteristic C ₁ in the target value generation circuit 105, no displacement occurs even if any force is applied from the work material, and the holder Withdrawal can be prevented, and precise processing can be performed by pulling. It is obvious that the inclination of the straight line portion of the characteristic C ₁ can be freely selected (the same applies to the following characteristics).

On the other hand, the characteristic C ₂ is the target value generation circuit 105.
It is a characteristic that the displacement is increased in response to the increase in the detected value of the force input to the, that is, the characteristic that the expansion body 14 is extended. Such characteristics can also be used for cutting, for example. Contrary to the above, when the rigidity of the work material is relatively low, a phenomenon occurs in which the work material escapes due to the cutting force during cutting. However, by using the characteristic C ₂ , when the force received from the work material increases, the tool is displaced toward the work material, that is, the tool positively plunges toward the work material. It is possible to deal with the phenomenon that the material escapes, and finally it is possible to prevent the deterioration of the processing accuracy due to the spring back.

The application of the characteristic C ₂ to cutting is applied when the cutting is performed from the surface of the work material, but the work material is cylindrical and the inner surface is cut. In this case, the movement of the tool is reversed, so the characteristic C ₃ is used (the same applies to the following characteristics). Further, this characteristic C ₃ is also a characteristic that is usually found in various devices, in that the characteristic is displaced in the direction of the force as the force increases.

Other characteristics will be briefly described below.
The characteristics C ₄ and C ₅ shown in FIG. 8 (b) are for preventing further displacement when the acting force exceeds a predetermined value.
A function as a stopper is added to the drive / detection structure 10. The characteristics C ₆ and C ₇ shown in (c) are characteristics in which the displacement decreases (escapes) when the acting force exceeds a certain value, and in the case of cutting processing, the inside of the work material is harder than the periphery. When present, it is used for processing in a mode in which the part is positively left uncut. Further, the characteristics C ₈ and C ₉ shown in (d) are characteristics in which the acting force is displaced in the opposite direction when the force exceeds a certain value. The holder retracts to prevent the system from being damaged.

FIG. 10 is a characteristic diagram when a force is selected by the selector 104 shown in FIG. 7 and the force F is controlled by the detected displacement amount D. The characteristic C ₁₀ shown in (a) is a characteristic of softness that keeps the force almost 0 even if a displacement occurs, and is used, for example, in a surface shape measuring probe or a surface roughness meter. Characteristic C ₁₁ shows a normal spring characteristic and can be used in general fields. The characteristic C ₁₂ is used, for example, when an element having a normal spring characteristic such as the characteristic C ₁₁ is coupled in series to form a flexible structure as a whole. There is a case where the shape measurement is performed by switching.

The characteristics C ₁₃ and C ₁₄ shown in (b) follow a normal movement (following movement (i.e., movement that does not increase the force and follows the shape of the opponent)) when a displacement of a certain value or more occurs in accordance with the normal spring characteristics. It is a characteristic to perform, and is a kind of automatic evacuation characteristic. The characteristics C ₁₅ and C ₁₆ shown in (c) are characteristics that reduce the force, for example, the pressing force, when a certain amount of displacement is reached. Such characteristics prevent the cracking of the back surface of the thin film caused by penetration by reducing the pressing force when processing to a certain depth from the thin film surface when performing drilling, milling, cutting, etc. on the thin film. It is used when The characteristics C ₁₇ and C ₁₈ shown in (d) are characteristics that generate a force in the opposite direction when the displacement reaches a certain amount, and are characteristics of fail-safe or stopper.

As described above, in the control device of the present embodiment, the target value generating circuit 105 is set to a target value of a certain characteristic so that the drive / detection structure 10 simply detects the displacement amount and the force. Alternatively, not only a function of giving a slight movement, but also a special function can be given according to a device to which the drive / detection structure 10 is applied.

The single drive / detection structure 10 shown in FIG. 1 has been described above. However, the drive / detection structure can be constructed with a structure other than that shown in FIG. Hereinafter, such a configuration example will be described with reference to the drawings.

FIG. 11 is a perspective view of a drive / detection structure according to the second embodiment of the present invention. In this figure, 20 shows the drive / detection structure of the present embodiment. 21a, 21b is rigid part, 22a _1, 22b ₁ are mutually parallel plate-shaped elastic body, 22a _2, 22b ₂ are each elastic member 22a _1, 2
2b ₁ has the same surface and is parallel to each other in the form of a plate-like elastic body,
Reference numerals 23a and 23b are joint portions, and 24 is joint portions 23a and 23b.
Is a stretchable body that is joined to. 25 is each elastic body 22a ₁ ~
22b ₂ is a strain gauge attached to the surface. 26
Is a rigid connecting body for connecting the rigid body portions 21a and 21b, 27
Is a through hole for forming the connecting body 26.

The drive / detection structure 20 of this embodiment is used in such a manner that each side surface of the rigid body portions 21a and 21b is fixed to the fixed portion, and a protruding portion is formed on the lower surface of the coupling portion 23b, and the protruding portion is fixed. There is a usage mode in which it is fixed to a part. In the former usage mode, the working end is E ₁ , whereas in the latter usage mode, the working end is E ₂ . Whereas the drive / detection structure 10 described above has a cantilever structure, the drive / detection body 20 of the present embodiment is used.
Has a symmetrical shape, and more stable operation is possible.

FIG. 12 is a side view of the drive / detection structure according to the third embodiment of the present invention. In this figure, reference numeral 30 shows the drive / detection structure of the present embodiment. 31 is a rigid body part, 31a,
31b are protrusions, 32a ₁ ~32b ₂ is similar to the elastic member and the elastic member 22a ₁ ~22b ₂ shown in FIG. 11, 33a ₁ to 3
3b ₂ is a connecting portion, 34 is a portion between the connecting portions 33a ₁ and 33b ₁ ,
And a stretchable body that is joined between the joining portions 33a ₂ and 33b ₂ . Each elastic body 34 is a cylindrical piezoelectric element, and the electrode 3
4e. 36 and 37 the elastic body 22a ₁ ~22b ₂
It is a through hole provided for forming. Note that FIG.
The elastic body 22a ₁ ~22b ₂ shown in 1 can also be configured by forming the same through hole and the through-hole 37, in which case the working end is the rigid part of the through hole. In this embodiment, the strain gauge is not shown. Protrusion 31
When b is fixed to the fixed part, the rigid part is fixed, and the working end is the protrusion 31a. In addition, when the protruding portion 31a is fixed to the fixing portion, it becomes a usage mode for fixing the expandable body,
The working end in that case becomes the protrusion 31b. The drive / detection body 30 of the present embodiment also has a symmetrical shape, and as in the second embodiment, a more stable operation is possible.

[0047] In the configuration described above elastics 34 are provided one on each side, but can either be provided around the rigid portion 31 3 or more, also, coupling portions 33a ₁ ～33B
It is also possible to make ₂ a circular shape and the elastic body 34 a cylindrical elastic body.

FIG. 13 is a perspective view of a drive / detection structure according to the fourth embodiment of the present invention. In this figure, reference numeral 40 indicates the drive / detection structure of the present embodiment. This drive / detection structure 4
0 is formed by stacking thin films. 41 is an insulating layer,
42 is a metal layer, 43 is a piezoelectric layer, 44 is a metal layer, and 45 is an insulating layer. These layers are sequentially laminated by means such as vapor deposition, sputtering and ion implantation.

In the laminated body of layers 41 to 45, 46a ₁ and 46a ₂ are two holes formed in parallel with the layers 45, 44 and 43 from above in the figure. On the other hand, although it is not clear in the drawing, the hole 46a is provided from the opposite side (lower side) of the laminate.
Holes parallel to the layers 41, 42 and 43 are drilled in the direction orthogonal to ₁ , 46a ₂ . By making such a hole, the outer frame-shaped rigid body portion 47, and the elastic bodies 48a ₁ and 48 that cross the frame-shaped rigid body portion 47 in one direction in the upper direction in the figure.
a ₂ , the frame-shaped rigid body portion 47 is attached to the elastic body 48 at the lower side in the figure.
Elastic body 4 that crosses in a direction orthogonal to the directions of a ₁ and 48a _2.
An elastic body 49 composed of 8b ₁ and 48b ₂ and a piezoelectric layer is formed.

Strain gauges are formed at predetermined locations on each elastic body. Metal layers 44 and 42 belonging to the upper and lower elastic bodies
Serves as an electrode of the elastic body 49. L is a lead wire connected to each electrode, and P is a probe fixed to the upper part of the elastic body 49 at the center of the elastic bodies 48a ₁ and 48a ₂ .

FIG. 13B is an enlarged perspective view of the lower elastic body 48b _{2 and its} vicinity. The metal layers 42 and 44 of the frame-shaped rigid body portion 47 are continuous with the metal layer of the elastic body only by making holes in the above-mentioned laminated body, and a voltage is applied to the elastic body 49 as it is. When the metal layer 4 of the frame-shaped rigid body portion 47
A voltage is also applied to 2 and 44, and the piezoelectric layer 43 sandwiched between them expands, which is inconvenient. For this reason, the metal layers 42 and 44 of the frame-shaped rigid body portion 47 and the upper and lower elastic metal layers are separated as indicated by a symbol G in (b).

The driving / detecting structure 4 thus configured
0 is used as a holder of a probe P of a so-called probe microscope such as an atomic force microscope and a tunnel microscope. Since the conventional holder has a cantilever shape in which the probe P is fixed to the tip, there is a problem that the rigidity is low and the direction of displacement changes. However, by using the drive / detection structure 40 as a holder, it is possible to obtain a holder having high rigidity and high natural frequency, and the direction of displacement is always constant.

FIG. 14 is a perspective view of a drive / detection structure according to the fifth embodiment of the present invention. In this figure, reference numeral 50 shows the drive / detection structure of the present embodiment. This drive / detection structure 5
0 is formed by stacking thin films. 51, 53, 5
Reference numerals 5 and 57 are metal layers, and reference numerals 52, 54 and 56 are piezoelectric layers, and these layers are sequentially laminated by means such as vapor deposition, sputtering and ion implantation. The laminated body thus laminated is constructed as shown by removing predetermined portions. Reference numeral 61 is a rigid body portion, 62a, b, and c are piezoelectric beams, 63 is an expandable body, and P is a probe attached to the expandable body 63. Like the drive / detection structure 40 of the previous embodiment, the drive / detection structure 50 of this embodiment is also used as a holder for a probe microscope.

In the above structure, the metal layers 53, 55 and the piezoelectric layer 54 in the elastic body 63 form an elastic member. Further, 64a ₁ and 64a ₂ are detection portions which are composed of the metal layers 57 and 55 and the piezoelectric layer 55 and detect charges generated in the beam 62a of the piezoelectric body, and 64b ₁ and 64b ₂ are the metal layer 5
A piezoelectric beam 62b made up of the piezoelectric layers 52 and 53.
Detectors for detecting electric charges generated in the detectors 64c ₁ and 64c ₂
Is a detection unit configured by the metal layers 51 and 53 and the piezoelectric layer 52 to detect electric charges generated on the beam 62c of the piezoelectric body.

When the drive / detection structure 50 of this embodiment is used in, for example, an atomic force microscope, when the probe P is opposed to the member to be measured at a minute interval, the probe P receives an atomic force, The beams 62a, 62b, and 62c are distorted in response to this force, and electric charges are generated accordingly, and the electric charges are detected by the detection units 64a _{1 to} 64c ₂ . The surface of the measurement target member by scanning with the probe P to collect the detected values of the detecting portions 64a ₁ ~64c _2. On the other hand, during the scanning, the expansion / contraction member composed of the metal layers 53 and 55 of the expansion / contraction member 63 and the piezoelectric layer 54 is expanded / contracted so that the probe P always receives a constant force. In this way, in the embodiment shown in FIGS. 13 and 14, the shape of the surface of the measurement target member can be measured.
An example in which the probe P is attached to the detection structures 40 and 50 has been given. However, it is obvious that if a diamond tip is attached instead of the probe P, it can be used as a fine processing apparatus. Further, in this case, if the expansion / contraction body 14 is driven at a high frequency, a vibration processing machine can be obtained. FIG. 15 shows a control device used as such a vibration processing machine.

FIG. 15 is a block diagram of a control device when the drive / detection structure is applied to a vibration processing machine. In this figure, the same or equivalent parts as those shown in FIG. 7 are designated by the same reference numerals. Reference numeral 109 is a high-frequency signal source, and 110 is an arithmetic unit. The output signal of the servo circuit 107 is added to the high frequency signal of the high frequency signal source 109 by the arithmetic unit 110 and output to the telescopic body drive circuit 108. Therefore, the elastic body 14
The (diamond tip) is vibrated at a high frequency and processed. The frequency of the high-frequency signal source 109 is the arithmetic unit 110.
The band is selected to be higher than the band of the servo system so that the high frequency signal output from is not suppressed by the servo system.

FIG. 16 is a side view of a moving mechanism for moving the driving / detecting structure. In this figure, 10 is the drive / detection structure shown in FIG. Reference numerals 71 and 72 denote supports fixed to the fixing portion A, 73 denotes a motor supported by the support 71, 7
Reference numeral 4 is a rod-shaped screw supported by the supports 71 and 72 and rotated by a motor 73, and 75 is a ball screw screwed with the screw 74. The drive / detection structure 10 is fixed to the ball screw 75. Drive / detection structure 10
When the displacement that can be generated by the above is small, there is a problem when the drive / detection structure 10 is applied to a device requiring a large stroke. However, with the above configuration, if a large stroke is obtained by the screw mechanism and a minute displacement is obtained by the drive / detection structure 10, the inconvenience can be eliminated.

In the above description, the drive / detection structure alone has been described. However, the drive / detection structure can be used not only as a single body but also as a composite structure of them. Hereinafter, a configuration in which a single drive / detection structure is combined will be described.

FIG. 17 is a diagram for explaining an aspect of the composite structure of the drive / detection structure. In this figure, (a) is a diagram schematically showing the drive / detection structure 10 shown in FIG. 1. (B) is a composite configuration in which the drive / detection structure 10 is coupled in series,
(C) shows a composite structure in which the drive / detection structures 10 are connected in parallel, and (d) shows a composite structure in which the drive / detection structures 10 are connected in directions orthogonal to each other. A specific example of the composite structure shown in (b) is shown in FIG. 17, and a specific example of the composite structure shown in (c) is shown in FIG.

It should be noted that the composite structure shown in (d) is not shown because the figure becomes complicated, but it is possible to easily perform such a combination without showing the figure. And
By setting the side indicated by the symbol K as the fixed end and the side indicated by the symbol S as the working end, the working end S can be displaced in the three axial directions. Further, although the composite structure of the three drive / detection structures 10 is shown in FIG.
Obviously, a composite configuration of 0 may be used.

FIG. 18 is a perspective view showing four specific examples of the series coupling shown in FIG. In these specific examples, two driving / detecting structures 10A and 10B are connected in series. (A) shows the rigid body portion 11 of the drive / detection structure 10B as the fixed end B ₁ , the elastic body 14 as the working end B ₂ , and the rigid body portion 11 of the drive / detection structure 10A as the fixed end A ₁ and stretchable body 14 and the end a _2, showing the structure that combines a fixed end a ₁ and working end B _2. (B) shows the stretchable body 14 of the drive / detection structure 10B with the fixed end B ₁ , the rigid body portion 11 with the working end B ₂ , the stretchable body 14 of the drive / detection structure 10A with the fixed end A ₁ , and the rigid body portion 11 acts. and the end a _2, showing the structure that combines a fixed end a ₁ and working end B _2. (C) is a rigid body portion 11 of the drive / detection structure 10B.
Is the fixed end B ₁ , the telescopic body 14 is the working end B ₂ , the telescopic body 14 of the drive / detection structure 10A is the fixed end A ₁ , the rigid portion 11 is the working end A ₂ , and the working end B ₂ and the fixed end A _{1 are} The configuration in which and are combined is shown. (D) is the expansion / contraction body 1 of the drive / detection structure 10B.
4 is the fixed end B ₁ , the rigid body portion 11 is the working end B ₂ , the rigid body portion 11 of the drive / detection structure 10A is the fixed end A ₁ , the telescopic body 14 is the working end A ₂ , and the working end B ₂ and the fixed end A _The configuration in which ₁ and are combined is shown. In such a series connection, one drive / detection structure having a large displacement characteristic is used.
If the other drive / detection structure having a minute displacement characteristic is used, a drive / detection structure having both coarse and fine movements can be constructed.

FIG. 19 is a perspective view showing three specific examples of the parallel connection shown in FIG. In these specific examples, two driving / detecting structures 10A and 10B are connected in parallel. (A) shows a structure in which the expansion / contraction bodies 14 of the drive / detection structures 10A and 10B are connected by a connecting portion 13, and the rigid body portions 11 of the drive / detection structures 10A and 10B are fixed ends A ₁ and B ₁ , respectively. And a structure in which the joint portion 13 has a common working end A ₂ B ₂ . (B) is a drive / detection structure 10A, 1
In this configuration, the rigid bodies 11 of 0B are shared (joined), and the elastic bodies 14 of the drive / detection structures 10A and 10B are fixed ends A ₁ and B ₁ , and the shared rigid body 11 is the working end A ₂ B. ₂ shows the configuration. (C) is a drive / detection structure 10A, 1
It is configured such that the stretchable body 14 and the rigid body portion 11 of 0B are opposed to each other, and the opposite stretchable body 14 and the rigid body portion 11 are joined at the ends on different sides, and the joining portion on one side of the end portion is a fixed end. A ₁ B ₁ and the coupling portion on the other side are working ends A ₂ B ₂ are shown.

In such a parallel connection, one driving / detecting structure is assumed to have a characteristic that the force detection range (rating) is small but the resolution is high, and the other driving / detecting structure displacement is set to the force detection range. If it has a characteristic that the resolution is large, but the resolution is somewhat low, it is possible to cope with forces of various magnitudes and also to cope with a desired detection accuracy.

Next, an example of a device to which a plurality of drive / detection structures 10 shown in FIG. 1 are applied will be illustrated. FIG. 20 is a perspective view of a fine movement table used for a processing device and a positioning device.
Such a fine movement table is disclosed in, for example, Japanese Patent Laid-Open No. 61-159.
No. 349, JP-A-62-88008, and the like. In FIG. 20, reference numeral 80 indicates a fine movement table. 8
Reference numeral 1 is a fixed portion fixed to an XY stage (not shown) or the like, and reference numeral 82 is a table on which a member to be processed or measured is placed. The fixed portion 81 and the table 82 are connected by the drive / detection structure 10 at their four corners.
By selectively driving the expansion / contraction body 14 of the drive / detection structure 10, translational (parallel) displacement in one axis direction (expansion / contraction direction) and rotation about two axes (around an axis orthogonal to the expansion / contraction direction) are performed on the table 82. ) Rotational displacement can be given. In this case, by controlling the characteristic C ₁ shown in FIG. 8, it is possible to increase the rigidity of the system including the table 82 and perform highly accurate machining and positioning.

FIG. 21 is a partially cutaway perspective view of the same fine movement table as in FIG. In this figure, the same or equivalent parts as those shown in FIG. 20 are designated by the same reference numerals. Reference numeral 83 indicates a fine movement table. The drive / detection structure 10 is shown as a straight line. 81a, 81b, 81c are positions on the fixed portion 81 to which one end of the drive / detection structure 10 is fixed,
Reference numerals a, 82b, and 82c denote positions on the table 82 to which the other end of the drive / detection structure 10 is fixed. The drive / detection structure 10 is provided between positions 81a and 82a, and positions 81b and 82b.
, Positions 81c and 82c, positions 81a and 82b, positions 81b and 82c, and positions 81c and 82a. The number of drive / detection structures 10 is six. By appropriately selecting and driving the expansion / contraction body 14 of the drive / detection structure 10, the table 82 has the same characteristics as the fine movement table shown in FIG. The rotational displacement of can be given.

[0066]

As described above, according to the present invention, the stretchable body, the rigid body portion, the elastic body connecting between both ends of the stretchable body and the rigid body portion, and between the both ends of the stretchable body and the rigid body portion. Since the drive / detection structure is composed of the detection means for detecting the displacement amount of, the detection and fine movement can be performed with a small and simple structure. Further, in the present invention, in the drive / detection structure having the above-mentioned structure, one of the detected values of the displacement and the force is selected, and the target value generating means for arbitrarily generating the characteristic of the target value is provided, and the selected detected value Since the stretchable body is driven according to the deviation from the target value according to the detected value, it is possible to use the apparatus in conformity with the device to be used.

[Brief description of drawings]

FIG. 1 is a perspective view of a drive / detection structure according to a first embodiment of the present invention.

FIG. 2 is a diagram modeling the drive / detection structure shown in FIG.

FIG. 3 is a diagram for explaining the operation of the drive / detection structure shown in FIG.

FIG. 4 is a diagram for explaining the operation of the drive / detection structure shown in FIG.

FIG. 5 is a diagram showing a specific example of a stretchable body of the drive / detection structure shown in FIG.

6 is a diagram showing a specific example of a detection unit of the drive / detection structure shown in FIG.

7 is a block diagram of a control device for the drive / detection structure shown in FIG. 1. FIG.

8 is a diagram showing characteristics of a target generation circuit of the control device shown in FIG.

9 is a side view of a drive / detection structure that operates according to the characteristics of the target generation circuit shown in FIG. 7. FIG.

10 is a diagram showing characteristics of a target generation circuit of the control device shown in FIG.

FIG. 11 is a perspective view of a drive / detection structure according to a second embodiment of the present invention.

FIG. 12 is a side view of a drive / detection structure according to a third embodiment of the present invention.

FIG. 13 is a perspective view of a drive / detection structure according to a fourth embodiment of the present invention.

FIG. 14 is a perspective view of a drive / detection structure according to a fifth embodiment of the present invention.

FIG. 15 is a block diagram of a control device for the drive / detection structure shown in FIG.

16 is a diagram showing a combination of the drive / detection structure and the long stroke mechanism shown in FIG. 1. FIG.

17 is a perspective view of a composite configuration of the drive / detection structure shown in FIG. 1. FIG.

FIG. 18 is a perspective view of the drive / detection structure shown in FIG. 1 connected in series.

FIG. 19 is a perspective view of the drive / detection structure shown in FIG. 1 connected in parallel.

20 is a perspective view of an application example of the drive / detection structure shown in FIG. 1. FIG.

21 is a perspective view of an application example of the drive / detection structure shown in FIG. 1. FIG.

FIG. 22 is a side view of a conventional force detector.

FIG. 23 is a side view of a conventional fine positioning device.

[Explanation of symbols]

 10 Drive / Detection Structure 11 Rigid Body Part 12a, 12b Elastic Body 14 Stretchable Body 15 Strain Gauge 20a, 20b Displacement Detector 23, 26 Operator 24 Selection Means 25 Target Value Generation Circuit 27 Servo Circuit 28 Stretchable Body Drive Circuit

Claims (26)

[Claims] 1. A stretchable body that stretches in a predetermined direction, a non-stretchable body facing the stretchable body, an elastic body that connects between both ends of the stretchable body and the non-stretchable body, and the stretchable body in the predetermined direction. A drive / detection structure comprising: a detection unit configured to detect a relative displacement amount between both ends of the stretchable body and the non-stretchable body. 2. The drive / detection structure according to claim 1, wherein the non-stretchable body is fixed to a fixed portion, and one end of the stretchable body is a working portion for an acted body. 3. The drive / detection structure according to claim 1, wherein one end of the stretchable body is fixed to a fixed portion, and one end of the non-stretchable body is a working portion for an acted body. . 4. A drive / detection structure comprising a plurality of single units of the drive / detection structure according to claim 1. 5. The drive / detection structure according to claim 4, wherein the combination is a combination in which the predetermined directions of the plurality of single bodies are parallel to each other. 6. The drive / detection structure according to claim 4, wherein the combination of the plurality of single bodies is a combination in which force transmission paths are in series. 7. The drive / detection structure according to claim 4, wherein the combination of the plurality of single bodies is a combination in which force transmission paths are in parallel. 8. The drive / detection structure according to claim 4, wherein the combination is a combination in which the predetermined directions of two or three of the single bodies are orthogonal to each other. 9. The drive / detection structure according to claim 1 or 4, wherein the elastic body is a thin plate that is deformable only in the predetermined direction. 10. The drive / detection structure according to claim 1, wherein the expandable body is a piezoelectric element. 11. The drive / detection structure according to claim 1, wherein the expandable body is an electrostrictive element. 12. The drive / detection structure according to claim 1, wherein the expandable body is a magnetostrictive element. 13. The drive / detection structure according to claim 1, wherein the expandable body is an electrostatic actuator. 14. The drive / detection structure according to claim 1, wherein the expandable body is an electromagnetic actuator. 15. The drive / detection structure according to claim 1 or 4, wherein the expandable body is an actuator that expands and contracts by supplying and discharging a fluid. 16. The drive / detection structure according to claim 1, wherein the expandable body is a member that expands and contracts by applied heat. 17. The elastic body according to claim 1 or 4, wherein the telescopic body is composed of a rotary motor and a conversion mechanism which is connected to the rotary motor and converts a rotary motion into a linear motion. Drive / detection structure. 18. The drive / detection structure according to claim 1 or 4, wherein the detection means is means for detecting strain of the elastic body. 19. The drive / detection structure according to claim 18, wherein the means for detecting strain is a strain gauge provided on the surface of the elastic body. 20. The driving / driving device according to claim 18, wherein the means for detecting the strain is a piezoelectric element.
Detection structure. 21. The drive / detection structure according to claim 1 or 4, wherein the detection means is means for detecting using a change in electrostatic capacitance. 22. The drive / detection structure according to claim 1 or 4, wherein the detection means is means for detecting by using light interference. 23. The drive / detection structure according to claim 1 or 4, wherein the detection means is means for detection using electromagnetic induction. 24. The drive / detection structure according to claim 1 or 4, wherein the drive / detection structure is moved by a moving mechanism having a stroke longer than an extension / contraction stroke of the extension / contraction body. 25. A stretchable body that stretches in a predetermined direction, a non-stretchable body facing the stretchable body, an elastic body that connects both ends of the stretchable body and the non-stretchable body, and the non-stretchable body in the predetermined direction. Displacement amount detection means for detecting each relative displacement amount between both ends of the stretchable body and the non-stretchable body, and both ends of the stretchable body and the non-stretchable body based on each detection value of these displacement amount detection means And a force detection means for detecting a force that causes relative displacement between the drive and detection structures. 26. The drive / detection structure control device according to claim 25, wherein selection means for selecting one of the detection values, and a characteristic of a target value of the force with respect to the displacement amount or a displacement amount with respect to the force. Target value generating means for arbitrarily generating characteristics of the target value, and calculating means for calculating a deviation between the target value generated by the target value generating means and the detected value selected by the selecting means according to the detected value. A control device for a drive / detection structure, comprising: an expansion / contraction body driving means for driving the expansion / contraction body according to the deviation obtained by the calculation means.