JPH07332914A - Touch signal probe - Google Patents

Abstract

PURPOSE:To improve the accuracy by obtaining a contact angle of an element to be measured and a contact part from the relationship between a detection signal detected by detecting means and a forced amount to the element to be measured of the contact part, and detecting the contact position according to the angle. CONSTITUTION:A touch signal probe comprises a stylus holder 12, a vibrator 14 supported substantially at its center to the holder 12 to be capable of vertically vibrating, a piezoelectric element 16 installed substantially at the center of the vibrator 14, an oscillator 18 and contact position detecting means 20 connected to the element 16. The vibrator 14 has a substantially spherical contact part 14A in contact with the element to be measured at the time of measuring at its lower end. The means 20 has a comparator for comparing whether the detection signal to be detected from a detecting electrode 16B is a predetermined value or not, a contact angle deciding circuit, etc. A contact latitude angle between the element to be measured and the part 14A is obtained from the relationship between the detection signal detected by the electrode 16B and the forced amount of the part 14A to the element to be measured, and the contact position is detected according to the angle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a touch signal probe, and more particularly to a touch signal probe used when measuring the shape of an object to be measured with a coordinate measuring machine or the like.

[0002]

BACKGROUND ART Three-dimensional measuring machines, contour measuring machines, etc. are known as measuring machines for measuring the shape and size of an object to be measured, but in order to detect coordinates and position in such cases, measurement is performed. The machine uses a touch signal probe that detects contact with the object to be measured.

As a touch signal probe, Japanese Patent Application No. 4-324201
The touch signal probe shown in No. 1 has been proposed. This touch signal probe is installed at a stylus holder, a vibrator having a substantially central portion supported by the stylus holder and a contact portion at one end for contacting an object to be measured, and a substantially central portion of the vibrator. This structure is provided with a piezoelectric element and detects the contact of the contact portion with the object to be measured from the vibration change of the vibrator. Here, the piezoelectric element has a function of a vibrating unit that vibrates the vibrator in the axial direction and a detecting unit that detects the contact of the contact portion with the object to be measured from the change in the vibration of the vibrator.

[0004]

Generally, what can be known by a measuring machine such as a coordinate measuring machine is the coordinate value of the center position of the contact portion. In the above-mentioned touch signal probe, the detection signal detected by the detection means has contact information between the contact portion and the object to be measured, but the contact position between the contact portion and the object to be measured cannot be detected. was there.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a touch signal probe in which the measurement accuracy is improved by obtaining the contact position between the contact portion and the object to be measured.

[0006]

According to the present invention, the contact angle between the object to be measured and the contact portion is obtained from the relationship between the detection signal detected by the detecting means and the amount of pushing of the contact portion with respect to the object to be measured. Is to achieve. Specifically, in the touch signal probe of the present invention, a vibrator having a contact portion that comes into contact with an object to be measured at one end and supported by a stylus holder, and a support point of the vibrator for the stylus holder are vibration nodes. In a touch signal probe having a vibrating means for vibrating a vibrator by means of a vibrator, and a detecting means for detecting a contact of the contact part with the object to be measured from a vibration change of the vibrator,
Contact for determining the contact angle between the object to be measured and the contact portion from the relationship between the detection signal detected by the detection means and the amount of pressing of the contact portion with respect to the object to be measured, and detecting the contact position according to this contact angle It is characterized in that it is provided with a position detecting means.

Here, the vibrator may be arranged such that the vibration direction thereof is the axial direction, and the contact portion may be formed in a substantially spherical shape. In this case, the contact position detection means includes a first comparator that detects that the detection signal detected by the detection means has reached a predetermined first signal level, and a detection signal detected by the detection means. A second comparator for detecting that a predetermined second signal level lower than the first signal level has been reached, and from the time when the first signal level is reached to the time when the second signal level is reached The time interval counting means for determining the time interval of, the contact latitude angle between the object to be measured and the contact portion from the relationship between the relative moving speed between the contact portion and the object to be measured and the time interval. It may be configured to include a contact angle determination circuit to be obtained.
Alternatively, the contact position detecting means may be the first and second contact position detecting means.
Comparator, speed accumulating means for fetching and accumulating moving speed data of the vibrator at every predetermined time from the time when the first signal level is reached to the time when the second signal level is reached, and the speed accumulating means. A contact angle determination circuit that determines the contact latitude angle between the object to be measured and the contact portion from the output of the means may be provided. Further, in addition to the above configuration, the contact angle determination circuit detects the first position where the vibrator is moved from a reference position in a predetermined direction (for example, a horizontal direction) and is in contact with the DUT, and , This first
Second position different from the first position at the same latitude as the position
May be detected, and the contact longitude angle between the contact portion and the object to be measured may be detected from the reference position, the first position, and the second position. The vibrating means and the detecting means may be composed of piezoelectric elements.

[0008]

In the present invention, upon measurement, the vibrator vibrated by the vibrating means is moved toward the object to be measured at a predetermined speed. When the contact portion of the vibrator comes into contact with the object to be measured, the detecting means detects the change in vibration of the vibrator. The detection signal detected by the detection means becomes smaller as the contact portion is pushed into the object to be measured. The detection signal and the pushing amount of the contact portion differ depending on the contact angle between the object to be measured and the contact portion. For example, when the vibration direction of the vibrator and the measured surface of the measured object are orthogonal (contact angle is 90 degrees),
Since the vibration of the oscillator is mechanically restrained in displacement, the detection signal is rapidly attenuated as the amount of pushing of the contact portion increases. On the other hand, when the vibration direction of the vibrator and the measured surface of the object to be measured are parallel (contact angle is 0 degree), the vibration of the vibrator is only constrained by the frictional force, so Even if becomes larger, the attenuation of the detection signal is gentle. As described above, the relationship between the detection signal and the pushing amount of the contact portion with respect to the measured object corresponds to the contact angle between the measured object and the contact portion. The corner or contact position can be detected.

Here, the vibrator is arranged so that the vibration direction is the axial direction, the contact portion is formed into a substantially spherical shape, and the contact position detection means detects a predetermined detection signal detected by the detection means. A first detecting that the first signal level has been reached
Comparator, a second comparator for detecting that the detection signal detected by the detecting means has reached a predetermined second signal level lower than the first signal level, and the first signal level is reached. From the relationship between the relative movement speed between the contact portion and the object to be measured and the time interval, the time interval counting means for obtaining the time interval from the time point when the second signal level is reached to the time point when the second signal level is reached. When a contact angle determination circuit for determining a contact latitude angle between the object to be measured and the contact portion is provided, when the detection signal is between the first signal level and the second signal level, The moving distance (pushing amount) of the vibrator is obtained from the time and the moving speed of the vibrator, and the contact latitude angle is obtained from the moving distance (pushing amount). For example, a ROM table in which the relationship between the amount of depression and the contact latitude angle is created in advance is provided in the contact angle determination circuit, and the contact latitude angle is obtained from the above-described movement distance (push amount). The center position (coordinate value) of the contact portion is obtained from the measuring device main body, and the radius of the contact portion is a known value. Therefore, if the contact latitude angle is obtained, the contact position of the contact portion can be obtained. When the detection signal is between the first signal level and the second signal level and the moving speed of the vibrator is constant, the pushing amount can be calculated from the product of the time interval and the moving speed. On the contrary,
The contact position detection means includes a first and a second comparator, and a moving speed of the vibrator at every predetermined time from the time when the first signal level is reached to the time when the second signal level is reached. If a configuration is provided that includes a velocity accumulating unit that captures and accumulates data and a contact angle determination circuit that obtains a contact latitude angle between the object to be measured and the contact portion from the output of the velocity accumulating unit, the moving velocity of the vibrator Is not constant, the pushing amount can be obtained by taking in and accumulating the moving speed data of the vibrator at a predetermined time interval from the time when the first signal level is reached to the time when the second signal level is reached. Further, the contact angle determination circuit detects the first position in contact with the object to be measured by moving the vibrator in a predetermined direction from the reference position, and then at the same latitude as the first position. If the second position different from the first position is detected, and the contact longitude angle between the object to be measured and the object to be measured is detected from the reference position, the first position and the second position, , The contact longitude angle as well as the contact longitude angle can be obtained, and a more accurate contact position of the contact portion can be obtained.

[0010]

The preferred embodiments of the touch signal probe according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a partial perspective view showing a main part of a touch signal probe according to an embodiment. In FIG. 1, the touch signal probe is installed in a stylus holder 12, a vibrator 14 whose substantially central portion is supported by the stylus holder 12, and which can vibrate in the vertical direction, and a substantially central portion of the vibrator 14. Piezoelectric element 16, an oscillator 18 and a contact position detecting means 2 respectively connected to the piezoelectric element 16.
It is configured with 0 and. The stylus holder 1
2 is formed in a hollow cylindrical shape, and the vibrator 14 is supported at its inner lower end by a pin 21 provided at a support point at a substantially central portion in the axial direction. The stylus holder 12 is attached to a moving shaft of a coordinate measuring machine (not shown), detects the contact with the object to be measured while the moving shaft moves, and measures the shape and the like by reading the coordinates at the time of contact.

The vibrator 14 has a substantially spherical contact portion 14A at its lower end which comes into contact with an object to be measured at the time of measurement, and the balancer 1 having the same weight as the contact portion 14A at its upper end.
It is a structure having 4B. Since this balancer 14B has the contact portion 14A attached to the lower end of the vibrator 14, the balancer 14B is weight-balanced so that the node of vibration does not separate from the center of the vibrator 14, and the entire touch signal probe. Is for preventing the moment around the support point from being received when acceleration is caused by moving in a direction crossing the vibration direction of the vibrator 14. Therefore, the balancer 14B may be the same sphere as the contact portion 14A.

The vibrator 14 is formed with a pair of groove portions 14C cut out in the outer peripheral portion as mounting portions for the piezoelectric element 16, and these two groove portions 14C each have the same shape. 16 is attached by an adhesive or the like. The piezoelectric element 16 is divided into a vibrating electrode 16A which is a vibrating means and a detecting electrode 16B which is a detecting means. Of these, the vibrating electrode 16A receives a signal from the oscillator 18. The vibrator 14 is vibrated in the axial direction (vertical direction in the figure). Since the two piezoelectric elements 16 undergo the same deformation at the same voltage, the vibrator 1
Vibration is applied to 4 and the vibration mode in the axial direction (Z-axis direction) is excited in the vibrator 14. Detection electrode 16B
Is for detecting the contact of the contact portion 14A with the object to be measured from the vibration change of the vibrator 14 and sending the detection signal to the contact position detecting means 20.

The structure of the contact position detecting means 20 is shown in FIG. In this figure, the contact position detecting means 20 has a comparison circuit 22 for comparing whether the value of the detection signal detected from the detection electrode 16B is a predetermined value or not, and a predetermined value in response to the signal from the comparison circuit 22. A logic circuit 24 that sends a signal, a clock circuit 26, an adder 28 that receives signals from the clock circuit 26 and the logic circuit 24 and generates a signal under a certain condition, and a signal from the adder 28 Gate circuit 30, accumulator 32 for accumulating data sent from gate circuit 30, and accumulator 32
And a contact angle determination circuit 34 that determines the contact angle between the contact portion 14A and the object to be measured.

The detection signal compared by the comparison circuit 22 is
The AC signal sent from the detection electrode 16B is a DC signal converted by an AC / DC converter (AD converter) not shown. This signal differs depending on the contact latitude angle between the contact portion 14A and the measurement surface of the measured object. For example, in FIG.
As shown in (A), when the vibrator 14 is moved in the direction of arrow P toward the measured surface O, the vibration direction of the vibrator 14 and the measured surface O are orthogonal to each other. Vibration is mechanically restrained from displacement. On the other hand, FIG.
As shown in (B), when the vibrator 14 is moved in the direction of the arrow Q toward the measured surface O, the vibration direction of the vibrator 14 and the measured surface O are parallel to each other. Vibration is restrained by frictional force. Thus, FIG. 3 (A)
In the case of (B), there is an essential difference in the constraint condition of the vibrator 14, and this causes a difference in detection sensitivity. FIG. 4A shows a state in which the contact portion 14A is in contact with the measured surface O, and the contact latitude angle is θ. Figure 4
(B) shows the relationship between the pushing amount and the detection signal with the contact latitude angle θ as a parameter. Here, the pushing amount is the distance that the contact portion 14A of the vibrator 14 further moves after coming into contact with the surface to be measured. As shown in FIG. 4B, the detection signal decreases as the pushing amount increases, but when the contact latitude angle θ is 0 °, the change of the detection signal is gradual, and as the contact latitude angle θ increases. The change of the detection signal becomes sudden and the contact latitude angle θ is 90.
When it is °, the change of the detection signal becomes the steepest.

As shown in FIG. 2, the comparison circuit 2
2 is a first comparator 36 for detecting that the detection signal has reached a predetermined first signal level (see FIG. 5).
And a second comparator 38 for detecting that the detection signal has reached a predetermined second signal level (see FIG. 5) lower than the first signal level. First
The comparator 36 sends the first trigger signal to the logic circuit 24 when the detection signal reaches the first signal level, and the second comparator 38 outputs the first trigger signal when the detection signal reaches the second signal level. 2 trigger signals are sent to the logic circuit 24. In the logic circuit 24,
The counting enable signal is generated until the second trigger signal is issued after the first trigger signal is issued. In the adder 28, while the counting permission signal is generated,
The clock signal sent from the clock circuit 26 is output to the gate circuit 30. In this gate circuit 30,
The probe movement speed data from the controller 40 of the coordinate measuring machine is sent to the accumulator 32 at a predetermined timing while the counting permission signal is generated. The accumulator 32 accumulates the probe moving speed data at predetermined time intervals, integrates the probe moving speed data during the generation of the counting signal (time t), and pushes the amount (position P _{1 in} FIG. 5). Amount of indentation between position P ₂ and position P ₂ ) is calculated. For example, if the moving speed of the transducer 14 is constant while the counting permission signal is generated, the product of the time t and the moving speed of the probe is the pushing amount. Therefore, when the moving speed fluctuates, the accumulator 32 functions as speed accumulating means for accumulating the moving speed data at a predetermined timing, and when the moving speed is substantially constant, the accumulator 32 operates. , And functions as time interval counting means for measuring the time interval between the first trigger signal and the second trigger signal.

The contact angle determination circuit 34 includes a latitude determination circuit that determines a contact latitude angle θ between the object to be measured and a contact portion, and a longitude determination circuit that determines a contact longitude angle β between the object to be measured and the contact portion.
And a correction circuit for determining the contact position between the object to be measured and the contact portion according to the contact latitude angle θ and the contact longitude angle β. The latitude determination circuit creates a ROM table in which the relationship between the push-in amount and the contact latitude angle θ is stored in advance, and this RO table is stored.
The contact latitude angle θ of the push amount data sent from the accumulator 32 is determined by referring to the push amount in the M table. If the moving speed of the vibrator 14 is constant, the relationship between the time t and the contact latitude angle θ is stored in the ROM table in advance, and the contact latitude angle θ is referred to by referring to the time t in the ROM table. To decide.

The contact longitude angle β determined by the longitude determination circuit is an angle formed by the X axis and the contact position in the horizontal plane as shown in FIG. In order to obtain the contact longitude angle β, as shown in FIG. 7, first, the center of the contact portion 14A is moved in the X-axis direction from the reference position O ₀ and brought into contact with the surface O to be measured to make the first position O ₁ After that, the center of the contact portion 14A is moved in the Y-axis direction from the reference position O ₀ to the position O _{2, and} then the center of the contact portion 14A is moved in the X-axis direction from the position O ₂ to be measured. The second position O ₃ is obtained by contacting the surface O. At this time, assuming that O ₂ −O ₀ = a and O ₃ −O ₂ = b, the contact longitude angle β is obtained from the equation of tan β = b / a. Here, the movement of the contact portion 14A from the positions O ₀ to O ₃ is performed at the same time as or before or after the step of obtaining the contact latitude angle θ. In the correction circuit, the coordinate position (the position of the center point) of the contact portion 14A obtained by the controller 40 of the coordinate measuring machine,
From the known radius of the contact portion 14A, the contact latitude angle θ determined by the latitude determination circuit, and the contact longitude angle β determined by the longitude determination circuit, the contact position between the object to be measured and the contact portion is obtained by a trigonometric function or the like. .

Therefore, according to this embodiment, the piezoelectric element 16
From the relationship between the detection signal detected by the detection electrode 16B (detection means) and the pushing amount of the contact portion 14A with respect to the measured object, the contact latitude angle θ between the measured object and the contact portion 14A.
Since the touch signal probe is provided with the contact position detecting means for detecting the contact position according to the contact latitude angle θ, the contact position between the contact portion 14A and the object to be measured can be calculated, and the measurement accuracy is improved. To do. Further, in the present embodiment, the vibrator 14 is arranged so that its vibration direction is the axial method, the contact portion 14A is substantially spherical, and the contact position detecting means 22 is constituted by the detecting electrode 16B. A first comparator 36 for detecting that the detected detection signal has reached a predetermined first signal level, and a second comparator 36 for which the detection signal detected by the detection electrode 16B is lower than the first signal level. A second comparator 38 for detecting that the signal level has been reached, and the object to be measured and the contact portion from the pushing amount from the time when the first signal level is reached to the time when the second signal level is reached. Since the contact angle determination circuit 34 for determining the contact latitude angle θ with the 14A is provided, it is possible to easily and surely determine the contact latitude angle which is actually a problem during measurement. In particular, if the moving speed of the vibrator 14 is constant, the time from the first comparator 36 issuing the first trigger signal to the second comparator 38 issuing the second trigger signal. The pushing amount can be easily calculated from the distance t and the moving speed of the vibrator 14, and the contact latitude angle θ can be obtained.

Further, the contact angle determination circuit 34 moves the vibrator 14 from the reference position O _{0 in the} horizontal direction to detect the first position O ₁ in contact with the object to be measured, and thereafter, the first position O ₁ is detected. The second position O ₃ which is different from the _first position O ₁ at the same latitude as the first position O ₁ is detected, and from these reference position O ₀ , the first position O ₁ and the second position O _3. DUT and contact part 14
Since the longitude determination circuit for detecting the contact longitude angle β with A is provided, not only the contact latitude angle θ but also the contact longitude angle β can be obtained, so that the measurement accuracy is further improved. In this respect,
Conventionally, a three-point measurement method is known in which the vibrator 14 is moved three times toward the surface O to be measured, the first to third positions are measured, and the contact longitude angle is obtained from these positions. In the present embodiment, the contact latitude angle θ is obtained by the latitude determination circuit, so the contact longitude angle β can be obtained by detecting the positions of two points.

Although the present invention has been described with reference to the preferred embodiment, the present invention is not limited to this embodiment, and various improvements and design changes can be made without departing from the scope of the present invention. Of course it is possible. For example, when the error of the contact longitude angle β is allowable, the contact latitude determination circuit 34 does not necessarily need to be provided with a longitude determination circuit. That is, as shown in FIG. 8A, the normal line of the measured surface O is inclined by the angle β with respect to the X axis, and when the contact portion 14A is located on this normal line, the angle β
Is the contact longitude angle. On the other hand, as shown in FIG. 8B, the vibrator 14 is inclined by the angle β with respect to the X axis, and the normal line of the measured surface O is inclined by the angle γ with respect to the X axis. In this case, the contact longitude angle is γ, so the error is (β-
γ). If the measured surface O is a smooth curved surface, the traveling direction β of the vibrator 14 and the contact longitude angle γ are approximately equal.
The error of the contact longitude angle β is allowable when the shape of the measured surface O is known in advance.

In the above embodiment, the contact position detecting means 22 includes the first and second comparators 37, 38,
Although the accumulator 32 and the contact angle determination circuit 34 are used, the contact position detection means of the present invention uses the relationship between the detection signal detected by the detection electrode 14B and the amount of pressing of the contact portion 14A with respect to the object to be measured. The object to be measured and the contact portion 1
The specific configuration does not matter as long as the configuration is such that the contact angle with 4A is obtained and the contact position is detected according to this contact angle. For example, the contact position detecting means measures a gradient pattern at various contact latitude angles θ in advance through experiments or the like, and stores the measured data as a graph of the pushing amount and the detection signal, and the actual measured data. A graph creating means for creating a graph of the pushing amount and the detection signal based on the above, and a comparing means for comparing the graph created by the graph creating means with the graph stored in the storing means to obtain the contact latitude angle θ. You may comprise.

Further, the vibrator 14 may have various shapes such as a conical shape, a tapered shape, and a conical shape. Further, the number of piezoelectric elements 14 and the mounting positions are not limited to those in the above-described embodiment. In short, if the transducer 14 has a vibration mode in the axial direction and there is no sensitivity difference in the direction perpendicular to the axis (longitudinal direction), but there is a sensitivity difference in the latitude direction (axial direction), the specific The shape is not limited. Further, in the above embodiment,
Arrange the vibrator 14 so that the vibration direction is the item direction,
Although the latitude determination circuit of the contact angle determination circuit 34 determines the contact latitude angle θ between the contact portion 14A and the object to be measured, in the present invention, the vibrator 14 is arranged so that the vibration direction is orthogonal to the axis. You can also do it. In this case, the contact longitude angle β of the contact portion 14A can be obtained with the same configuration as the latitude determination circuit. Further, although the vibrating means is the vibrating electrode 16A of the piezoelectric element 16, in the present invention, a vibrating means combining a magnetostrictive element and a coil, or a coil and an iron piece may be used. Further, the detection means is the detection electrode 16B of the piezoelectric element 16, but in the present invention, a combination of a strain gauge or a permanent magnet and a coil may be used. Furthermore, in the above-described embodiment, the case where the present invention is applied to a coordinate measuring machine has been described, but the present invention is not limited to this, and can be applied to a two-dimensional measuring machine, a contour measuring machine, and the like. Further, in the above embodiment, the piezoelectric element 16 was vibrated by the oscillator 18,
In the present invention, the piezoelectric element 16 may be vibrated by self-oscillation.

[0023]

As described above, according to the present invention,
Contact for detecting the contact angle between the object to be measured and the contact part from the relationship between the detection signal detected by the detection means and the amount of pushing of the contact part of the vibrator with respect to the object to be measured, and detecting the contact position according to this contact angle Since the touch signal probe is provided with the position detecting means, not only the center of the contact portion but also the contact position between the contact portion and the object to be measured can be obtained, and the measurement accuracy is improved. Further, in the present invention, the vibrator is arranged so that the vibration direction thereof is the axial direction, and the contact portion is substantially spherical,
Further, the contact position detecting means is configured to detect the detection signal detected by the detecting means reaching a predetermined first signal level, and the detection signal detected by the detecting means. A second comparator that detects that a second signal level that is lower than the first signal level is reached, and a pushing amount from the time when the first signal level is reached to the time when the second signal level is reached. A time interval counting means or velocity accumulating means for calculating, and a contact angle determination circuit for determining the contact latitude angle between the object to be measured and the contact portion from the relationship between the previously determined indentation amount and the contact latitude angle,
With such a configuration, it is possible to reliably and easily determine the contact latitudinal angle that is a practical problem during measurement. further,
The contact angle determination circuit detects the first position in contact with the object to be measured by moving the vibrator in the horizontal direction from the reference position, and then detects the first position at the same latitude as the first position. If the second position different from the position is detected and the longitude of the object to be measured is detected from the reference position, the first position and the second position, not only the contact latitude angle but also the contact longitude angle Can also be obtained, so that the measurement accuracy can be further improved.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a touch signal probe according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a contact position detecting means.

3A and 3B are diagrams schematically showing a relationship between a vibration state of a vibrator and a moving direction of the vibrator.

FIG. 4 (A) is a schematic view showing a state where the contact portion is in contact with the surface to be measured at a contact latitude angle θ, and FIG. 4 (B) is a relationship between the pushing amount and the detection signal with the contact latitude angle as a parameter. It is a graph showing.

FIG. 5 is a graph showing a relationship between a push-in amount and a detection signal at a predetermined contact latitudinal angle, showing a region of the detection signal detected by the first comparator and the second comparator.

FIG. 6 is a schematic perspective view showing a relationship between a contact latitude angle θ and a contact longitude angle β of a contact portion.

FIG. 7 is a schematic diagram illustrating a step of obtaining a contact longitude angle β of a contact portion.

FIG. 8A is a schematic plan view showing a case where the normal line of the measured surface O is inclined by an angle β with respect to the X axis, and FIG. FIG. 6 is a schematic plan view showing a case in which it is inclined by an angle γ.

[Explanation of symbols]

12 stylus holder 14 vibrator 14A contact part 16 piezoelectric element 16A excitation electrode 16B as excitation means 16B detection electrode as detection means 20 contact position detection means 32 accumulator as time interval counting means and speed accumulation means 34 contact Angle determination circuit 36 First comparator 38 Second comparator

Claims (4)

[Claims] 1. A vibrator supported by a stylus holder having a contact portion at one end for contacting an object to be measured, and a vibrating vibrator that vibrates the vibrator by using a supporting point of the vibrator as a node of vibration. A touch signal probe having means for detecting contact of the contact portion with an object to be measured from a change in vibration of the vibrator, wherein the detection signal detected by the detection means and the measured portion of the contact portion are measured. A touch signal probe, comprising a contact position detection means for determining a contact angle between the object to be measured and the contact portion from the relationship with the amount of pushing into the object and detecting the contact position according to the contact angle. 2. The touch signal probe according to claim 1, wherein the vibrator is arranged so that a vibration direction thereof is an axial direction, the contact portion is formed in a substantially spherical shape, and the contact position detecting means is A first comparator for detecting that the detection signal detected by the detection means has reached a predetermined first signal level; and a predetermined comparator for which the detection signal detected by the detection means is lower than the first signal level. A second comparator for detecting that the second signal level has been reached; and a time interval counting means for obtaining a time interval from the time when the first signal level is reached to the time when the second signal level is reached. A contact angle determination circuit for determining a contact latitude angle between the object to be measured and the contact portion from the relationship between the relative moving speed between the contact portion and the object to be measured and the time interval. Characterized by Chi signal probe. 3. The touch signal probe according to claim 1, wherein the vibrator is arranged such that a vibration direction thereof is an axial direction, the contact portion is formed in a substantially spherical shape, and the contact position detecting means is A first comparator for detecting that the detection signal detected by the detection means has reached a predetermined first signal level; and a predetermined comparator for which the detection signal detected by the detection means is lower than the first signal level. A second comparator that detects when the second signal level is reached, and a movement of the vibrator at every predetermined time from the time when the first signal level is reached to the time when the second signal level is reached. A touch signal probe comprising: a speed accumulating means for taking in and accumulating speed data; and a contact angle determining circuit for obtaining a contact latitude angle between the object to be measured and the contact portion from an output of the speed accumulating means. Boo. 4. The touch signal probe according to claim 2 or 3, wherein the contact angle determination circuit detects the first position where the vibrator is moved from a reference position and is in contact with the object to be measured, , A second position different from the first position at the same latitude as the first position is detected, and the object to be measured and the contact portion are detected from the reference position, the first position and the second position. A touch signal probe characterized by detecting the contact longitude angle of.