JP4399052B2 - Operation control structure of touch signal probe - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a stylus having a contact portion that contacts a measurement object at the tip, a stylus holder that supports the stylus, a vibration unit that resonates the stylus in the axial direction at a frequency f1, and the vibration unit that uses the vibration unit. The present invention relates to an operation control structure of a touch signal probe that performs operation control of a touch signal probe including a detecting unit that detects a change in vibration of a stylus.
[0002]
[Background]
Height gauges (one-dimensional measuring instruments), three-dimensional measuring instruments, and contour measuring instruments are known as measuring instruments that measure the shape and dimensions of the object to be measured. In these measuring instruments, various probes are used to detect the positional relationship between the measuring instrument body and the object to be measured. These probes are classified into non-contact probes and contact probes, or continuous measurement probes and touch trigger probes.
An ultrasonic touch signal probe disclosed in Japanese Patent Application Laid-Open No. 6-221806 is known as a contact touch trigger probe for a coordinate measuring machine.
[0003]
The touch signal probe disclosed in the publication includes a stylus having a contact portion that contacts a measurement object, a stylus holder that supports the stylus, a vibration unit that resonates the stylus in an axial direction, and the vibration source. Detecting means for detecting a change in the vibration of the stylus by the means.
According to such a touch signal probe, when the tip portion is brought into contact with the end surface of the object to be measured in a state where the stylus is vibrated by the vibration means, the vibration state of the stylus is changed by the contact force. By detecting by the detection means, the position of the end face of the object to be measured can be detected.
[0004]
  On the other hand, such an ultrasonic touch signal probe may be used to measure a small hole diameter, etc., and in order to enable measurement of small holes, etc., as an ultrasonic touch signal probe that has been downsized,Japanese Patent Application No. 10-220474A touch signal probe shown in FIG.
  As shown in FIG. 17, the touch signal probe 100 includes a stylus holder 101, a stylus 102, a vibration means 103A, and a detection means 103B. The tip of the stylus 102 is provided with a contact portion 102A that comes into contact with the object to be measured, and a counter balance 102B is provided at the base end thereof, and the center position in the axial direction of the stylus 102 is the center of gravity. When the stylus 102 is vibrated in the axial direction, the vibration node becomes the position of the center of gravity.
[0005]
In such a touch signal probe 100, the stylus 102 is formed of a thin rod-like member and the contact portion 102A is formed of a small-diameter spherical body in accordance with the stylus 102 in order to enable measurement of a small hole. . Further, since it is difficult for the stylus holder 101 to support such a thin stylus 102 at one place, the stylus 102 supports the stylus 102 at two places across the center of gravity of the stylus 102.
[0006]
The vibration means 103A and the detection means 103B are configured by dividing the piezoelectric element 103 arranged so as to straddle two support portions of the stylus holder 101 into two parts. Then, when the stylus 102 is resonated along the axial direction by the vibration means 103A, a vibration node is generated at the center of gravity of the stylus 102, and the support portion of the stylus 102 of the stylus holder 101 sandwiches the vibration node. It is considered as a position.
[0007]
According to such a touch signal probe 100, since the stylus holder 101 supports the stylus 102 at two positions with the vibration node interposed therebetween, even if the stylus 102 is configured by a very thin rod-shaped member, the stylus holder 101 The inner surface of a small hole having a large aspect ratio can be measured.
[0008]
[Problems to be solved by the invention]
However, when continuous measurement is performed along the inner surface of a small hole or the like with the touch signal probe 100 for small hole measurement described above, there are the following problems.
That is, in the touch signal probe 100, since the shaft rigidity of the stylus 102 becomes low as a result of reducing the shaft diameter of the stylus 102, the side surface of the object to be measured, etc. while the contact portion 102A is in contact with the object to be measured. When the stylus is moved along the stylus 102, the stylus 102 is deflected and a so-called adhesion phenomenon occurs.
[0009]
This adhesion phenomenon is not a major problem if only the presence or absence of contact between the object to be measured and the contact portion 102A is detected. However, when continuous contact measurement is performed along the end surface of the object to be measured, There is a problem that phase delay occurs, and mechanical deformation occurs due to adhesion force, resulting in a position error.
[0010]
An object of the present invention is to provide an operation control structure of a touch signal probe that can prevent a stylus adhesion phenomenon caused by contact with an object to be measured and can perform continuous measurement along the surface of the object to be measured. is there.
[0011]
[Means for Solving the Problems]
  In order to achieve the above object, an operation control structure of a touch signal probe according to the present invention includes:
  A stylus having a contact portion at the tip that comes into contact with the object to be measured, a stylus holder that supports the stylus, vibration means for resonating the stylus at a frequency f1 in the axial direction, vibration of the stylus by the vibration means An operation control structure of a touch signal probe that performs operation control of a touch signal probe provided with a detecting means for detecting a change,
  A support that is mechanically coupled to the stylus holder and moves at a predetermined velocity vector in a three-dimensional space by a driving mechanism;
  A vibration element that vibrates the stylus at a frequency f2 in a direction orthogonal to the axial direction of the stylus, and a means for controlling the vibration direction of the vibration element in the normal direction of the end face of the object to be measured.A second excitation means;
  Control means for controlling the drive mechanism to operate the support in a direction along the end surface of the object to be measured and a direction along the vibration direction of the stylus by the second vibration means; With
  The control means starts scanning the measurement object by bringing the contact portion into contact with an end surface of the measurement object while vibrating the stylus by the second vibration means, and the detection means during the scanning The movement in the direction along the end face of the object to be measured and the movement in the direction along the vibration direction of the stylus by the second vibration means so that the minimum value of the detected signal to be detected becomes a constant value. It is characterized by controlling.
[0012]
According to the operation control structure of the touch signal probe having such a configuration, the touch signal probe can be used for continuous measurement of the surface of the object to be measured while avoiding the adhesion phenomenon as follows.
That is, as shown in FIG. 1A, the contact portion 102A of the stylus 102 is arranged in the vicinity of the end face of the object to be measured W, and vibrates at the frequency f2 in the normal direction of the end face of the object to be measured by the second vibration means. If it does, contact part 102A will repeat contact and non-contact with the end face of to-be-measured object W, and will perform what is called a tapping operation.
[0013]
  At this time, the vibration at the frequency f1 in the axial direction of the stylus 102 by the vibration means is free vibration in the non-contact state, and the vibration is constrained by the contact force F in the contact state, and as shown in FIG. As the force F increases, the amplitude A of the vibration of the stylus 102 in the axial direction decreases. Here, as shown in FIG. 2, the detection signal V representing the change in vibration (for example, the amplitude of vibration) detected by the detection means has a vibration period (1 / f2) of the frequency f2 by the second vibration means. Depending on,Minimum value of detection signal during scanningTake Va.
  In this state, as shown in FIG. 3, when the stylus 102 is moved in the B direction along the end face of the workpiece W, the detection signal V is as shown in FIG.Minimum value of detection signal during scanningTake Va and every vibration periodMinimum value of detection signal during scanningVa is constant.
[0014]
  On the other hand, as shown in FIG. 4, when the moving direction B of the stylus 102 is tilted with respect to the end surface of the object W to be measured, the change in the detection signal V due to the tapping operation causes As the distance gradually approaches, the contact force of the contact portion 102A increases, and the extreme value Va changes as shown in FIG.
  Therefore, the detection signal V is a predetermined value.Minimum value of detection signal during scanningTake Va and theMinimum value of detection signal during scanningIf the operation of the touch signal probe 100 is controlled by the control means so that Va becomes constant, the touch signal probe 100 moves along the end surface of the workpiece W and continuously measures the end surface of the workpiece W. Can be done. And saidMinimum value of detection signal during scanningBy setting Va so as not to exceed a predetermined value, the mechanical phase delay can be set to a very small state, and it is possible to prevent the detection position error caused by the adhesion phenomenon from occurring. It is possible to perform continuous measurement of the end face.
[0015]
Specifically, as shown in FIG. 6, the second oscillating means may perform operation control such that the stylus 102 approaches and separates in the direction C along the vibration direction perpendicular to the axial direction of the stylus, By repeating the operation in the direction B and the operation in the direction C, the stylus 102 can be moved along the end surface of the workpiece W.
[0016]
In the above, as the control means described above, a control means for operating the support in a direction orthogonal to the normal line of the end surface of the object to be measured can be employed.
Specifically, the control means moves the support along the X-axis direction, the Y-axis direction of the XY table on which the object to be measured is placed, and the Z-axis direction which is the normal direction of the XY table surface. What is necessary is just to comprise so that it may control.
[0017]
That is, when such a control means is employed, as shown in FIG. 7, when measuring the inner surface of the small hole W1 formed in the workpiece W, the contact portion 102A is arranged in the inner circumferential direction of the small hole. It becomes possible to move along H, and continuous measurement of the opening part of the small hole W1 is attained. Further, as shown in FIG. 7, the contact portion 102A can be moved in the depth direction D of the small hole W1, and continuous measurement in the depth direction of the small hole W1 becomes possible.
[0018]
Further, as the above-described vibration means and the second vibration means, the vibration means and the second vibration means constituted by two vibration elements arranged so as to form 90 ° around each other around the stylus axis. Can be adopted.
Further, as the other vibration means and the second vibration means, the vibration means and the second vibration means composed of at least three or more vibration elements arranged at equal intervals around the stylus axis are adopted. can do.
A piezoelectric element can be employed as the above-described vibration element.
[0019]
Such a vibration means and a second vibration means can be configured by arranging piezoelectric elements on the surface of a cylindrical body through which a rod-like stylus is inserted. The piezoelectric elements may be provided so as to form an angle, or the three piezoelectric elements may be provided equally on the cylindrical surface so as to form an angle of 120 degrees.
Then, by giving two types of frequencies f1 and f2 to each piezoelectric element, the stylus can be vibrated in the axial direction at the frequency f1, and the stylus can be vibrated in the bending direction at the frequency f2.
[0020]
Specifically, the frequency f1 is set to a natural frequency that causes the stylus to resonate in the axial direction, and the frequency f2 is set to a frequency that is equal to or lower than the natural frequency that causes the stylus to vibrate in the bending direction.
If the frequency f1 is synchronously applied to each piezoelectric element, the axial force of each piezoelectric element is not canceled out, so that the stylus can resonate in the axial direction.
On the other hand, if a frequency f2 is applied to a plurality of piezoelectric elements arranged at 90 ° around the stylus axis or at equal intervals, the force in the bending direction of the stylus of each piezoelectric element is synthesized and acts on the stylus. Therefore, it is possible to set the vibration surface of the vibration by the second vibration means in an arbitrary direction around the stylus axis.
[0021]
The second vibration means described above can be provided separately from the vibration means, and can be configured to vibrate the stylus holder in two directions perpendicular to the axis of the stylus.
Specifically, the second vibration means can be configured by providing in series a vibration element that vibrates in one direction between the stylus holder and the support and a vibration element that vibrates in a different direction. it can.
Further, the other second vibration means can be configured by providing a plurality of vibration elements in parallel on the surface of the cylindrical body that supports the stylus holder provided with the vibration means.
Since such second vibration means is provided separately from the vibration means, the present invention can be implemented using a touch signal probe provided with a conventionally known vibration means. It is possible to easily replace only the stylus while leaving the second vibration means.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, parts that are the same as or similar to the parts or members that have already been described are assigned the same reference numerals, and descriptions thereof are omitted or simplified.
FIG. 8 shows an inner / outer surface measuring apparatus incorporating the operation control structure of the touch signal probe according to the first embodiment of the present invention.
[0023]
The inner / outer surface measuring apparatus 1 includes a measuring instrument main body 2, a controller 3, a drive circuit 4, a detection circuit 5, and a personal computer 6. The drive circuit 4 is for vibrating the touch signal probe 100 in the axial direction of the stylus and in a direction perpendicular to the axis, and the detection circuit 5 processes an electrical signal from detection means provided in the stylus to control the controller. 3 is a portion to be output. In addition, the personal computer 6 outputs a control signal to the controller 3 to control the operation of the measuring instrument main body 2, and the detection signal from the detection circuit 5 is input via the controller 3 to calculate the detection signal. Go and evaluate the roundness of the workpiece W.
[0024]
The measuring device main body 2 is for measuring the surface shape by setting the workpiece W. The XYZ table 21 on which the workpiece W is set, the support column 22 standing on the end of the XYZ table 21, and the The support 23 is provided so as to be slidable in the extending direction of the column 22, and the touch signal probe 100 is supported by the support 23.
Although the XYZ table 21 is not shown in FIG. 8, an X-axis adjustment mechanism and a Y-axis adjustment mechanism that move the work W along the surface of the XYZ table 21 in order to place the work W at a predetermined position, And a Z-axis adjusting mechanism that moves the workpiece W in the normal direction of the surface of the XYZ table 21. Then, after the work W is placed on the XYZ table 21, these axis adjustment mechanisms are operated to perform accurate and accurate position adjustment of the work.
[0025]
Although not shown in FIG. 8, the support 23 is supported by the X and Y axes driving mechanisms that move the touch signal probe 100 along the surface of the XYZ table 21, and the support 23 up and down along the column 22. These axis drive mechanisms are controlled by a controller 3 to be described later.
The controller 3 is a part that controls the operation of the support 23, and includes a control means 31 and an avoidance means 32.
[0026]
  The control means 31 controls the operation of the support 23 of the measuring instrument body 2 based on the measurement start signal from the personal computer 6, and the detection signal V from the detection circuit 5Minimum value of detection signal during scanningTake Va and theMinimum value of detection signal during scanningThe operation of the support 23 is controlled so that Va is constant (see FIG. 2).
  The avoiding means 32 detects that the detection signal V from the detection circuit 5 is a predetermined value.Minimum value of detection signal during scanningWhen Va cannot be maintained, the operation control by the control unit 31 is stopped, and a control signal for moving the support 23 in the direction opposite to the movement direction of the touch signal probe 100 by the control unit 31 is output. . By this avoiding means 32, the touch signal probe 100 is brought into a non-contact state with the workpiece W, and damage due to an excessive contact force is prevented.
[0027]
As shown in FIG. 9, the touch signal probe 100 includes a stylus holder 101, a stylus 102, a contact portion 102A, a counter balance 102B, a vibration means 103A, and a detection means 103B. And between the support body 23 and the stylus holder 101 supported by this support body 23, the 2nd vibration means 110 which vibrates the stylus 102 in the direction orthogonal to the axis | shaft of this stylus 102 is provided. In order to vibrate the stylus 102 in an arbitrary direction within a plane perpendicular to the axis of the stylus 102, the second vibration means 110 includes an X-axis vibration element 110X and a Y-axis vibration element that vibrate in directions orthogonal to each other. The vibration element 110 </ b> Y is provided, and the X-axis vibration element 110 </ b> X and the Y-axis vibration element 110 </ b> Y are arranged in series between the stylus holder 101 and the support body 23.
[0028]
The drive circuit 4 is a portion that provides an electrical signal at a predetermined frequency to the vibration means 103 </ b> A and the second vibration means 110, and includes a vibration circuit 41 and a second vibration circuit 42.
The vibration circuit 41 includes a transmitter that generates an electrical signal that causes the vibration means 103A to operate at a predetermined amplitude and a predetermined frequency, whereby the stylus 102 vibrates in the axial direction at the frequency f1.
[0029]
The second vibration circuit includes a transmitter that generates an electrical signal that operates the X-axis vibration element 110X and the Y-axis vibration element 110Y described above at a predetermined amplitude and a predetermined frequency. In this transmitter, the X-axis vibration element 110X and the Y-axis vibration element 110Y are operated in synchronization, but the amplitudes of the electric signals of the vibration elements 110X and 110Y can be independently adjusted. . Then, by applying electric signals having different amplitudes to the respective excitation elements 110X and 110Y, the stylus 102 vibrates in an arbitrary direction, and by synchronizing the vibrations of the two excitation elements 110X and 110Y, the stylus 102 has the frequency It vibrates in an arbitrary direction orthogonal to the axis of the stylus 102 at f2.
[0030]
Next, the operation of the inner diameter measuring apparatus 1 according to the first embodiment described above will be described in the case of measuring the inner surface of the small hole W1 as shown in FIG.
(1) As shown in FIG. 10, the position coordinates of the center O of the inner diameter of the small hole W1 and the approximate radius R are acquired in advance by three-point measurement or the like.
(2) Considering the amplitude of the stylus 102 by the second vibration means 110, a circle S1 smaller than the radius R by Δr is set in the control means 31 as a basic motion locus of the contact portion 102A. Specifically, the operation control of the contact portion 102A is performed based on the angle θ from the measurement start point P0 and the radius R−Δr in FIG. In addition, since the amplitude of the vibration orthogonal to the axis of the stylus 102 by the vibration means 2 is extremely small, this Δr can actually be considered as a value substantially equal to the radius of the contact portion 102A.
[0031]
(3) The electric signal of the second vibration circuit 42 is set as a function of the angle θ so that the vibration of the stylus 102 by the second vibration means 110 is in the normal direction of the inner surface of the small hole W1. The X-axis vibration element 110X and the Y-axis vibration element 110Y constituting the two vibration means 110 are operated. Specifically, the direction connecting the center point O of the circle S1 and the measurement start point P0 is the vibration direction of the X-axis vibration element 110X, and the axis of the stylus 102 of the X-axis vibration element 110X and the Y-axis vibration element 110Y. When the maximum force in the orthogonal direction is F and the frequency by the second vibration circuit is f2, the force Fx in the X-axis direction by the X-axis vibration element 110X and the force Fy in the Y-axis direction by the Y-axis vibration element 110Y are Is set as the following function.
Fx = F · sin (2π · f2 · t) · cos θ
Fy = F · sin (2π · f2 · t) · sinθ
Accordingly, the contact portion 102A taps the inner surface of the small hole W1 at a predetermined period (1 / f2).
(4) The stylus 102 is vibrated in the axial direction by the vibration means 103B, and the control means 31 starts scanning the inner surface of the small hole W1 while tapping the inner surface of the small hole W1 with the contact portion 102A.
[0032]
(5) During scanning, the detection signal V from the detection means 103BMinimum value of detection signal during scanningWhen Va changes as shown in FIG. 5, that is, when the inner circumference of the small hole W1 is deviated from the arc locus S1 set by the control means 31, it changes.Minimum value of detection signal during scanningVa is input to the control means 31 via the detection circuit 5, and the control means 31 moves the stylus 102 along the vibration surface by the second vibration means 110,Minimum value of detection signal during scanningThe operation of the support 23 is controlled so as to return to Va. In particular,Minimum value of detection signal during scanningIf the change is such that Va becomes small, the control means 31 controls the operation in a direction in which the contact portion 102A moves away from the inner surface of the small hole W1 toward the center point O,Minimum value of detection signal during scanningIf the change is such that Va increases, the operation is controlled so that the contact portion 102 approaches the inner surface of the small hole W1 from the center point O.
[0033]
(6) The detection signal V from the detection means 103BMinimum value of detection signal during scanningWhen Va cannot maintain a predetermined value even by the operation of the control means 31, the controller 3 stops the operation control of the support 23 by the control means 31 and causes the avoidance means 32 to perform the avoidance operation. Specifically, the avoidance unit 32 operates the support 23 in the direction opposite to the operation direction by the control unit 31.
(7) On the other hand, when measuring the depth direction of the small hole W1, the control means 31 should just control operation | movement so that the support body 23 may be operated up and down. When the support body 23 is controlled to operate downward, when the contact portion 102A comes into contact with the surface of the XYZ table 21, the detection signal V becomes smaller than the detection signal in the non-contact state throughout. Therefore, the support body 23 is moved upward by the avoidance means 32.
[0034]
  According to the first embodiment as described above, there are the following effects.
  That is, the contact portion 102A taps the inner surface of the small hole W1 that is the object to be measured, and the detection signal V at that time isMinimum value of detection signal during scanningSince the control means 31 controls the operation of the support 23 so as to take Va, it is possible to prevent an excessive force in the bending direction from acting on the stylus 102 and in a state in which the mechanical phase delay is extremely small. The measurement of the inner surface of the small hole W1 can be performed, the detection position error due to the adhesion phenomenon is prevented, and the inner surface of the small hole W1 can be measured.
[0035]
  Further, since the control means 31 is configured to control the drive mechanism that moves the support 23 in the X-axis direction, the Y-axis direction, and the Z-axis direction of the XYZ table 21, it is three-dimensional like the small hole W1. Even an object to be measured having a complicated inner surface can be continuously measured.
  Further, the detection signal VMinimum value of detection signal during scanningWhen Va changes, the control means 31 is configured to control the operation of the support 23 in the direction of approaching or separating the vibration surface of the vibration by the second vibration means 41, so that the contact portion 102A always has a constant contact force. Thus, the inner surface of the small hole W1 can be brought into contact, and continuous measurement by the touch signal probe 100 can be performed with high accuracy.
[0036]
  Since the operation control structure of the touch signal probe includes the avoidance means 32, the detection signal V from the detection means 103B isMinimum value of detection signal during scanningWhen Va cannot be maintained, the support 23 can be moved in a direction opposite to the operation direction of the support 23 by the control unit 31, and an excessive contact force is prevented from acting on the stylus 102, and the touch signal probe 100. Therefore, the touch signal probe 100 can also be used in measurement of blind holes and the like.
  Further, since the second vibration means 110 is provided separately from the vibration means 103B, a touch signal probe provided with a conventionally known vibration means 103B can be used, and has various shapes and sizes. The present invention can be implemented with a touch signal probe.
[0037]
Next, a second embodiment of the present invention will be described.
In the operation control structure of the touch signal probe according to the first embodiment described above, the touch signal probe 100 includes the vibration means 103A provided on the stylus holder 101, and the second vibration means 41 includes the support 23 and the stylus holder 101. The two excitation means 102A and 41 are driven by independent excitation circuits 41 and 42, respectively.
[0038]
On the other hand, in the operation control structure of the touch signal probe according to the second embodiment, the vibration means and the second vibration means are integrally provided around the axis of the stylus constituting the touch signal probe. Is different.
That is, as shown in FIG. 11, a touch signal probe 200 according to the second embodiment is sandwiched between a stylus holder 201 and two support pieces 201A provided on the stylus holder 201, and a cylindrical body through which the stylus 102 is inserted. 202.
[0039]
As shown in FIG. 12, four piezoelectric elements 203A, 203B, 203C, and 203D are provided on the outer periphery of the cylindrical body 202, and are arranged so as to form a 90 ° around the axis of the stylus 102. The two piezoelectric elements 203A and 203B serve as vibration elements, and constitute vibration means and second vibration means.
The piezoelectric elements 203C and 203D arranged to face the piezoelectric elements 203A and 203B are configured as detection means, and the detection signal V output from each of the piezoelectric elements 203C and 203D is processed by the detection circuit 5.
Note that the other parts of the touch signal probe 200 and the structure of the inner / outer surface measuring device to which the touch signal probe 200 is attached are the same as those in the first embodiment, and thus the description thereof is omitted.
[0040]
Although not shown in FIG. 12, the piezoelectric elements 203A and 203B are driven by electric signals of two types of frequencies f1 and f2, respectively, from the vibration circuit. One is the natural frequency f1 of the stylus 102 in the axial direction, and the other is the frequency f2 of the stylus 102 in the bending direction.
The forces FA1 and FB1 that cause the piezoelectric elements 203A and 203B to vibrate at the natural frequency f1 are synchronized, and FA1 = FB1, so that the stylus 102 resonates in the axial direction.
[0041]
On the other hand, the forces FA2 and FB2 in the direction orthogonal to the axis of the stylus 102 of the piezoelectric elements 203A and 203B generated by the frequency f2 are measured starting points on the circle S1 centered on the center point O with reference to FIG. From the clockwise angle θ with P0 as the base point, it is as follows.
FA2 = F · sin (2π · f2 · t) · cos θ
FB2 = F · sin (2π · f2 · t) · sinθ
When measuring the inner surface of the small hole W1 shown in FIG. 10 with such a touch signal probe 200, first, the center position coordinates O and the radius R of the inner diameter of the small hole are obtained as in the first embodiment. After that, the touch signal probe 200 is moved in a direction such that θ = 0, and is brought into contact with the inner surface of the small hole W1. The piezoelectric elements 203C and 203D as detection means output a resonance state change of the natural frequency f1 due to the contact to the detection circuit 5, recognize this position coordinate, and continuously detect it along the inner surface of the small hole W1. By doing so, it is possible to grasp the inner surface shape of the small hole W1.
[0042]
Here, what should be noted when attaching the above-described touch signal probe 200 to the support is the above-described direction of θ = 0. Since this is a structural problem determined by the arrangement of the piezoelectric elements 203A and 203B constituting the vibration means and the second vibration means, when the touch signal probe 200 is mounted on the support, the axis of the stylus 102 It is necessary to uniquely determine the surrounding positions.
[0043]
According to the second embodiment as described above, in addition to the effects described in the first embodiment, there are the following effects.
That is, since the frequency f1 is synchronously applied to the piezoelectric elements 203A and 203B, the axial forces FA1 and FB1 of the piezoelectric elements 203A and 203B constituting the excitation means are not canceled, and the stylus 102 is Resonate in the direction.
[0044]
In addition, since the piezoelectric elements 203A and 203B constituting the second vibration means are arranged at 90 ° around the axis of the stylus 102, the force FA2 in the bending direction of the stylus 102 of each pressure line element 203A and 203B. , FB2 are combined and act on the stylus 102, and the vibration surface of the stylus 102 by the second vibration means can be set in any direction around the axis of the stylus 102, and the inner surface of the small hole W1 is continuous. Measurements can be made.
[0045]
Furthermore, since the vibrating means and the second vibrating means are integrally formed on the cylindrical body 202, the touch signal probe 200 can be reduced in size, and a small hole having a smaller diameter can be measured. Can do.
Unlike the case of the first embodiment, there is no need to separately provide the second vibration means between the support 23 and the stylus holder 101, so that the operation of the touch signal probe according to the present invention can be performed with various inner and outer surface measuring devices. The control structure can be implemented and its versatility is significantly improved.
[0046]
Next, a third embodiment of the present invention will be described.
In the touch signal probe 200 according to the second embodiment described above, the four piezoelectric elements 203A to 203D are integrally provided on the cylindrical body 202 disposed around the stylus 102, and are disposed so as to form 90 ° C. with respect to each other. Piezoelectric elements 203A and 203B constitute the vibrating means and the second vibrating means.
[0047]
On the other hand, as shown in FIG. 13, the touch signal probe 300 according to the third embodiment is the same as the touch signal probe 200 according to the second embodiment with respect to the stylus holder 210, the stylus 102, the contact portion 102A, and the like. However, the difference is that six piezoelectric elements are equally arranged on the outer periphery of the cylindrical body 302 through which the stylus 102 is inserted.
[0048]
That is, as shown in FIG. 14, the piezoelectric elements 303A, 303B, 303C, 303D, 303E, and 303F are provided at equal intervals on the outer periphery of the cylindrical body, and are equally arranged at 120 ° around the axis of the stylus 102. The three piezoelectric elements 303A, 303C, and 303E arranged in FIG. 5 serve as the vibration element, and constitute the vibration means and the second vibration means, and the piezoelectric elements that are arranged to face the three piezoelectric elements 303A, 303C, and 303E. 303B, 303D, and 303F constitute detection means.
[0049]
The three piezoelectric elements 303A, 303C, and 303E that constitute the vibrating means and the second vibrating means are synchronously provided with a signal having a frequency f1 that vibrates the stylus 102 in the axial direction, and the stylus 102 is An electric signal having a frequency f2 that is oscillated in a direction orthogonal to is provided. The force in the direction perpendicular to the axis of the stylus 102 is given as the resultant force generated by the vibration of the three piezoelectric elements 303A, 303C, 303E at the frequency f2.
[0050]
The touch signal probe 300 according to the third embodiment has the following effects in addition to the effects described in the second embodiment.
That is, since the piezoelectric elements 303A, 303C, and 303E are equally arranged around the axis of the stylus 102 so as to form 120 ° from each other, the stylus 102 is orthogonal to each other regardless of the arrangement of the piezoelectric elements 303A, 303C, and 303E. If it is a direction, the stylus 102 can be vibrated in an arbitrary direction.
In addition, since the piezoelectric elements 303A, 303C, and 303E are arranged on the axis without any deviation, the tapping operation of the stylus 102 can be made uniform in any direction within the measurement surface.
Further, with such a configuration, it becomes easy to reduce the influence of variations in the characteristics of the piezoelectric elements.
[0051]
Next, a fourth embodiment of the present invention will be described.
The touch signal probe 200 according to the second embodiment described above has a cylindrical body 203 through which the shaft of the stylus 102 is inserted, and the piezoelectric elements 203A and 203B provided on the outer peripheral portion of the cylindrical body 203 include the vibration means and the first. It had the role of 2 vibration means.
On the other hand, the touch signal probe 400 according to the fourth embodiment includes a plurality of piezoelectric elements 403A provided on a cylindrical body 402 through which the shaft of the stylus 102 is inserted, as shown in FIGS. Another difference is that a piezoelectric element 103A is separately provided at the center of gravity of the stylus 102, the piezoelectric element 403A serves as the second vibrating means, and the piezoelectric element 103A serves as the vibrating means.
[0052]
That is, as shown in FIG. 15, the touch signal probe 400 includes a stylus 102, a contact portion 102A, a counter balance 102B, a stylus holder 201, a second stylus holder 401, a cylindrical body 402, and a base 410 as a support. Composed. The cylindrical body 402 has a proximal end fixed to the base 410 and a second stylus holder 401 attached to the distal end, and is held between the base 410 and the second stylus holder 401.
[0053]
A plurality of piezoelectric elements 403A are provided in parallel on the outer periphery of the cylindrical body 402, and these constitute a second vibration means. The plurality of piezoelectric elements 403 </ b> A are provided on the outer periphery of the cylindrical body 403 and are arranged at equal intervals.
The second stylus holder 401 is a cylindrical body in which a step is formed at an intermediate portion of the side surface, and the cylindrical body 402 is fitted to the upper portion of the step having a small outer radius, and a slit formed on the cylindrical side surface of the stylus holder 401. 401A and a fixing screw 401B are provided.
[0054]
As shown in FIG. 16, the stylus 102 is supported by the stylus holder 201 at two positions so as to sandwich the position of the center of gravity that becomes the node of the axial vibration, and the stylus holder 201 includes the excitation means 103A made of piezoelectric elements and the detection unit. Means 103B are provided.
The stylus holder 201 is inserted into the slit 401A of the second stylus holder 401, and is fixed to the second stylus holder 401 by a fixing screw 401B.
An electric signal having a frequency f2 is given to the piezoelectric element 403A constituting the second vibration means from a second vibration circuit (not shown), and the frequency f1 is given to the piezoelectric element 103A constituting the vibration means from the vibration circuit. The electrical signal is given. Note that the direction of the vibration plane in the vibration in the direction orthogonal to the axial direction of the stylus 102 is given as a combined vector of the plurality of piezoelectric elements 403A, as in the second embodiment, and a description thereof will be omitted.
[0055]
The touch signal probe 400 according to the fourth embodiment has the following effects in addition to the effects described in the second embodiment.
That is, since the piezoelectric element 403A provided on the cylindrical body 402 does not require detection electrodes, the number of the piezoelectric elements 403A can be relatively small, and the structure of the touch signal probe 400 can be simplified.
[0056]
In addition, since the piezoelectric element 103A causing the axial vibration of the stylus 102 and the piezoelectric element 403A causing the vibration in the direction orthogonal to the axis are separated, the tapping operation of the stylus 102 is changed to the axial vibration of the stylus 102. Without affecting, it is possible to obtain axial vibrations without disturbance and perform highly accurate measurement.
[0057]
Further, when considering the change of the stylus 102, the second oscillating means is not provided integrally with the stylus 102, so that the stylus 102 is replaced while the piezoelectric element 403 </ b> A serving as the second oscillating means remains unchanged. This can reduce the cost of parts.
The piezoelectric element 403A on the cylindrical body 402 serving as the second vibrating means and the piezoelectric element 103A serving as the vibrating means are provided separately, and the stylus 102 is fixed to the second stylus holder 401 by the fixing screw 401B. Therefore, a conventionally known touch signal probe can be used, and the stylus 102 can be easily replaced.
[0058]
Note that the present invention is not limited to the above-described embodiments, and includes modifications as described below.
The operation control structure of the touch signal probe according to the first embodiment has been used to measure the inner surface of the small hole W1, but is not limited thereto. That is, the present invention may be used to continuously measure the outer peripheral surface of a cylindrical workpiece or a workpiece having another complicated three-dimensional shape.
[0059]
Moreover, in the said 2nd Embodiment, although the vibration means and the 2nd vibration means were comprised from piezoelectric element 203A, 203B, it is not restricted to this, A vibration means and a 2nd vibration means are comprised by another structure. It may be configured. In short, any other configuration may be employed as long as it is a vibration means and a second vibration means that can vibrate the stylus at a predetermined frequency in the axial direction and in a direction orthogonal to the axis.
In addition, the specific structure, shape, and the like when implementing the present invention may be other structures as long as the object of the present invention can be achieved.
[0060]
【The invention's effect】
According to the operation control structure of the touch signal probe of the present invention as described above, the contact portion can be tapped with respect to the end surface of the object to be measured by the second vibration means, thereby avoiding the adhesion phenomenon. The touch signal probe can perform continuous measurement along the surface of the object to be measured.
[Brief description of the drawings]
FIG. 1 is a schematic diagram and a graph for explaining the operation of the present invention.
FIG. 2 is a graph showing changes in detection signals for explaining the operation of the present invention.
FIG. 3 is a schematic diagram showing the moving direction of the stylus and the arrangement of the end face of the object to be measured for explaining the operation of the present invention.
FIG. 4 is a schematic diagram showing the moving direction of the stylus and the arrangement of the end face of the object to be measured for explaining the operation of the present invention.
FIG. 5 is a graph showing a change in a detection signal for explaining the operation of the present invention.
FIG. 6 is a schematic diagram showing the operation control of the touch signal probe by the operation control structure of the touch signal probe according to the present invention.
FIG. 7 is a schematic diagram showing a scanning direction of the touch signal probe by the operation control structure of the touch signal probe according to the present invention.
FIG. 8 is a schematic diagram illustrating an operation control structure of the touch signal probe according to the first embodiment of the present invention.
FIG. 9 is a schematic diagram showing the structure of a touch signal probe in the embodiment.
FIG. 10 is a schematic diagram for explaining a measurement procedure in the embodiment.
FIG. 11 is a schematic perspective view showing the structure of a touch signal probe of the operation control structure of the touch signal probe according to the second embodiment of the present invention.
FIG. 12 is a schematic diagram showing the arrangement of the vibration means and the second vibration means in the embodiment.
FIG. 13 is a schematic perspective view showing a structure of a touch signal probe of an operation control structure of a touch signal probe according to a third embodiment of the present invention.
FIG. 14 is a schematic diagram showing the arrangement of the vibration means and the second vibration means in the embodiment.
FIG. 15 is a schematic perspective view showing a structure of a touch signal probe of an operation control structure of a touch signal probe according to a fourth embodiment of the present invention.
FIG. 16 is a schematic perspective view showing the structure of a stylus and vibration means in the embodiment.
FIG. 17 is a schematic perspective view showing the structure of a conventional touch signal probe.
[Explanation of symbols]
1. Operation control structure of touch signal probe
23 Support
31 Control means
100, 200, 300, 400 Touch signal probe
101, 201, 401 Stylus holder
102 Stylus
102A contact area
103A Exciting means
103B detection means
110 Second vibration means
203A, 203B, 303A, 303C, 303E Piezoelectric elements (excitation means and second excitation means)
403A Piezoelectric element as second vibrating means
D Stylus axial direction
H Tangent direction of vibration surface
V detection signal
VaMinimum value of detection signal during scanning
W DUT

Claims (7)

A stylus having a contact portion at the tip that comes into contact with the object to be measured, a stylus holder that supports the stylus, vibration means for resonating the stylus at a frequency f1 in the axial direction, vibration of the stylus by the vibration means An operation control structure of a touch signal probe that performs operation control of a touch signal probe provided with a detecting means for detecting a change,
A support that is mechanically coupled to the stylus holder and moves at a predetermined velocity vector in a three-dimensional space by a driving mechanism;
A second element having a vibration element that vibrates the stylus at a frequency f2 in a direction orthogonal to the axial direction of the stylus, and a means for controlling the vibration direction of the vibration element in the normal direction of the end face of the object to be measured. Shaking means;
Control means for controlling the drive mechanism to operate the support in a direction along the end surface of the object to be measured and a direction along the vibration direction of the stylus by the second vibration means; With
The control means starts scanning the measurement object by bringing the contact portion into contact with an end surface of the measurement object while vibrating the stylus by the second vibration means, and the detection means during the scanning The movement in the direction along the end face of the object to be measured and the movement in the direction along the vibration direction of the stylus by the second vibration means so that the minimum value of the detected signal to be detected becomes a constant value. An operation control structure of a touch signal probe characterized by controlling. The operation control structure of the touch signal probe according to claim 1 ,
The operation of the touch signal probe is characterized in that the excitation means and the second excitation means are composed of two excitation elements arranged at 90 ° around the axis of the stylus. Control structure. The operation control structure of the touch signal probe according to claim 1 ,
Operation control of a touch signal probe, wherein the excitation means and the second excitation means are composed of at least three or more excitation elements arranged at equal intervals around the axis of the stylus. Construction. In the operation control structure of the touch signal probe according to claim 2 or 3 ,
An operation control structure of a touch signal probe, wherein the vibration element is composed of a piezoelectric element. The operation control structure of the touch signal probe according to claim 1 ,
The second vibration means vibrates the stylus holder in two directions perpendicular to the axis of the stylus. The operation control structure of the touch signal probe according to claim 5 ,
The second vibration means is configured by arranging in series a vibration element that vibrates the stylus holder in one direction and a vibration element that vibrates in a different direction. Motion control structure. The operation control structure of the touch signal probe according to claim 5 ,
2. The touch signal probe operation control structure according to claim 2, wherein the second vibration means is configured by arranging a vibration element in one direction and a vibration element in a different direction in parallel.

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