JP4956058B2 - Surface texture measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface property measuring apparatus for achieving a high-accuracy profile measurement by a fixed measurement force without increasing a measurement time even if there is a fluctuation in a characteristic and a disturbance in a surface property of a measured object. <P>SOLUTION: The surface property measuring apparatus includes: a force sensor 1; a drive actuator 11; a detector 12; a profile controlling means 54 for capturing a detection signal from the force sensor 1, and driving the drive actuator so as to match the detection signal with a target measurement force; a touch signal generating section 51 for generating a touch signal when the detection signal from the force sensor 1 is matched with the target measurement force; and a measurement value capturing means 55 for capturing a measurement value of a counter 26 at predetermined intervals while a fluctuation width of the detection signal from the force sensor 1 is less than a preset fixed width, and capturing a measurement value of a latch counter 52 every time the touch signal is generated while the detection signal from the force sensor 1 is oscillated and its amplitude exceeds the preset fixed width when the profile controlling means operates. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a surface texture measuring device. For example, the present invention relates to a surface property measuring apparatus that measures surface properties such as the shape and surface roughness of an object to be measured using an excitation type force sensor.

Surface texture measuring devices that measure the surface properties such as the shape and surface roughness of the object to be measured by scanning the surface of the object to be measured, such as roughness measuring machine, contour measuring machine, roundness measuring machine, and three-dimensional measuring machine It has been known.
In such a measuring machine, an excitation type force sensor is used as a sensor for detecting the surface of the object to be measured based on a minute displacement in which the contact portion contacts the surface of the object to be measured.

<Excitation type force sensor>
As shown in FIG. 10, the vibration-type force sensor 1 (measurement unit) includes a metal base 2, a stylus 3 formed integrally with the base 2, and a vibration (vibrates in the axial direction) of the stylus 3. ) And the detection element 5 that detects the vibration state of the stylus 3 and outputs it as a detection signal. A stylus 6 as a contact portion composed of a diamond tip, a ruby or the like is bonded and fixed to the tip of the stylus 3. The vibration element 4 and the detection element 5 constitute measurement force detection means for detecting measurement force when the stylus 6 of the stylus 3 comes into contact with the surface of the object to be measured, and are constituted by one piezoelectric element. The base 2 is bonded and fixed to each of the front and back surfaces.

As shown in FIG. 11, when an excitation signal Pi (voltage signal) having a specific frequency and amplitude is given to the vibration element 4 of the force sensor 1, the detection element 5 has a specific frequency and amplitude. Detection signal Qo (voltage signal) is obtained.
FIG. 12 shows the amplitude change of the detection signal Qo accompanying the contact with the workpiece W. When the excitation signal Pi having a constant amplitude at the resonance frequency of the stylus 3 is applied to the excitation element 4 when the stylus 3 is not in contact with the workpiece W, the stylus 3 resonates and the detection element 5 has an amplitude. Ao detection signal Qo is obtained. When the stylus 3 comes into contact with the workpiece W, the amplitude of the detection signal Qo is attenuated from Ao to Ax.

There is a relationship shown in FIG. 13 between the attenuation rate k (Ax / Ao) and the measuring force.
Here, the case where the detection signal Qo when the stylus 3 (force sensor 1) contacts the workpiece W is attenuated to 90% of the non-contact state (a state where the attenuation factor k = 0.9) is taken as an example. Take. From the relationship of FIG. 13, it can be seen that the measuring force in this contact state is 135 [μN].
Accordingly, when the force sensor 1 is brought into contact with the workpiece W, the distance between the force sensor 1 and the workpiece W is controlled using a driving actuator or the like so that the attenuation rate k is always constant. The shape and roughness of the workpiece W can be measured with a constant force.

<Shape measurement system using force sensor>
FIG. 14 is an example of a shape measuring system using the force sensor 1. This shape measuring system includes a probe 10 and a controller 20 that controls the probe 10.
The probe 10 includes a force sensor 1, a drive actuator 11 that moves the force sensor 1 back and forth with respect to the object W to be measured, and a displacement amount of the force sensor 1 by the drive actuator 11 (that is, a measurement target by the force sensor 1. It comprises a detector (consisting of a scale and a detection head) 12 for detecting the measurement position information of the object W).

  The controller 20 includes an oscillator 21 that applies an excitation signal to the force sensor 1 to vibrate the force sensor 1, a peak hold circuit 22 that converts a detection signal from the force sensor 1 into a DC signal, and a peak hold circuit 22. A calculator 23 for calculating a deviation between the output (force sensor signal) and the target measurement force, a force control compensator 24 having the output from the calculator 23 as an input, and an output from the force control compensator 24 A drive amplifier 25 that drives the drive actuator 11 based on the signal and a counter 26 that counts a signal from the detector 12 and outputs the measurement position information of the force sensor 1 as a position measurement value.

  In FIG. 14, when the stylus 3 of the force sensor 1 is brought into contact with the workpiece W, a detection signal at that time is output from the force sensor 1. Then, the detection signal is converted into a DC signal by the peak hold circuit 22 and then given to the calculator 23. The calculator 25 calculates a deviation between the detection signal (force sensor signal) from the peak hold circuit 22 and the target measurement force. Since the deviation is multiplied by the gain of the force control compensator 24 and the result is given to the drive amplifier 25, the drive actuator 11 drives the deviation to eliminate the deviation.

<Method of using force sensor as a scanning probe>
FIG. 15 shows a change in the detection signal (force sensor signal) from the force sensor 1 when the force sensor 1 shifts from the non-contact state to the contact state.
When the force sensor 1 is further pushed after being brought into contact with the workpiece W, the detection signal (force sensor signal) from the force sensor 1 gradually decreases and is stable in a state substantially in agreement with the target measurement force. To do. In this state, when the force sensor 1 and the object to be measured are relatively moved along the surface shape of the object to be measured, the detection signal from the force sensor 1 and the target measuring force are kept substantially in agreement. Therefore, if the position measurement value from the detector 12 is read, the shape and roughness of the object to be measured can be measured while measuring force is constant.

<Method of using force sensor as touch probe>
In the shape measurement system of FIG. 14, by incorporating a circuit for latching the current position when the attenuation rate reaches a desired value, the force sensor 1 can be used as a touch probe with a constant measurement force.
As shown in FIG. 16, the force sensor 1 represents the detection signal amplitude of the force sensor 1 and the contact detection level (threshold value) for detecting that the object has been contacted. A circuit that outputs a touch signal indicating contact with the object to be measured is constructed. In this configuration, since the touch signal is generated when the force sensor signal exceeds the contact detection level (threshold), the same measurement force is always generated at the timing when the touch signal is generated ( High accuracy).
In addition, as shown in FIG. 17, the measurement force can be controlled by controlling the contact detection level (threshold), and by increasing the contact detection level, a measurement with a lower measurement force is possible and an ultra-high accuracy measurement is possible. It becomes.

<Probe with both constant force measurement function and touch measurement function>
As can be seen from the above description, the use method (detection principle) of the force sensor is the same whether it is used as a scanning probe or a touch probe.
Therefore, conventionally, both a scanning measurement function and a touch measurement function are installed, and the probe mounting part itself is driven by a three-dimensional drive mechanism that drives in a three-dimensional space. A system that switches between and uses has been proposed (see Patent Document 1).

  There are cases in which constant force tracking control is difficult due to fluctuations in characteristics depending on the surface shape, surface properties, and material of the object to be measured and disturbances input to the system. If the constant force scanning control is difficult, that is, if the force control is unstable, the scanning control becomes oscillatory, and the measurement values vary and high accuracy cannot be maintained. As a complementary function in that case, the constant force scanning measurement and the touch measurement are switched and used.

  For example, in the case shown in FIG. 18, if the scanning control becomes oscillatory in the middle of the scanning measurement, the measurement value varies and high accuracy cannot be maintained. Manually switch from measurement mode to touch measurement mode. Alternatively, when the vibration amplitude of the force sensor signal exceeds a predetermined value set in advance, the scanning measurement mode is switched to the touch measurement mode. Further, the surface shape of the object to be measured is estimated in advance, and when the touch measurement area is entered, the scanning measurement mode is automatically switched to the touch measurement mode. Then, the force sensor contacts the surface of the object to be measured while repeating the so-called touch-back operation after coming away from the surface of the object to be measured. The measured value is taken in.

Japanese Patent Application No. 2005-254016

However, in order to supplement the shape scanning measurement with normal touch measurement, it is necessary to perform touch measurement at a pitch shorter than the shape cycle to be measured, which has a disadvantage that the measurement time becomes long.
Also, in general, when measuring a fine shape, the constant force scanning measurement is smaller than the touch measurement, because the discrete interval of the measurement data is narrower and it is possible to measure to a fine shape period. This is better than touch measurement. Accordingly, it has been desired to use constant force scanning measurement as much as possible.

  The object of the present invention is to realize a surface property capable of realizing a high-precision scanning measurement with a constant measuring force even if there is a characteristic fluctuation or disturbance due to the surface property of the object to be measured. It is to provide a measuring device.

  The surface texture measuring apparatus according to the present invention includes a stylus having a contact portion that contacts the surface of the object to be measured, and a measurement force detecting unit that detects a measuring force when the contact portion contacts the surface of the object to be measured. A relative movement means for relatively moving the measurement section and the object to be measured, and a position detection means for outputting the measurement position of the measurement object by the measurement section as measurement position information. A surface texture measuring device that captures measurement position information from the position detection means while driving the relative movement means in contact with the surface of the object to be measured, and measures the surface texture of the object to be measured from the measurement position information. A scanning control means for taking in the detected measurement force from the measurement section and driving the relative movement means so that the detected measurement force substantially coincides with a target measurement force; and a detection from the measurement section When a constant force is taken in and the detected measurement force coincides with the contact measurement force, a touch signal generation unit that generates a touch signal, and a fluctuation range of the detection measurement force from the measurement unit when the scanning control unit is operating. In a state of less than a predetermined fixed width, the measurement position information from the position detection means is taken in based on a predetermined condition, the detected measurement force from the measurement unit vibrates and the amplitude exceeds a predetermined fixed width Then, each time a touch signal is generated from the touch signal generation means, a measurement value acquisition means for acquiring measurement position information from the position detection means is provided.

According to the present invention, the detected measurement force from the measurement unit is taken into the scanning control unit, and the relative movement unit is driven by the scanning control unit so that the detected measurement force substantially matches the target measurement force. Accordingly, the surface property of the object to be measured is measured in a state where the stylus of the measuring unit is brought into contact with the object to be measured and the detected measurement force at this time is controlled to substantially match the target measurement force.
At this time, in a state where the fluctuation range of the detection measurement force from the measurement unit is less than a predetermined fixed range, the measurement position information from the position detection unit is captured based on a predetermined condition. Therefore, in this state, measurement by normal scanning measurement can be realized. Here, the predetermined condition means a predetermined time interval or a predetermined distance interval.
On the other hand, if the detected measurement force from the measurement unit vibrates and the amplitude exceeds a preset fixed width during scanning measurement, for example, the characteristics change due to the shape, material, surface properties, etc. of the object to be measured When the detected measurement force from the measurement unit becomes oscillating due to a disturbance or a disturbance, the measurement force fluctuates, resulting in variations in measurement values.
In this state, every time a touch signal is generated from the touch signal generating means, measurement position information from the position detecting means is taken in. Since the timing at which the touch signal is generated is when the detected measurement force coincides with the contact measurement force, a measurement value with a constant measurement force can be captured. Of course, since the measurement is not performed by switching from the scanning measurement to the touch measurement, the time loss associated with the so-called touch back operation can be eliminated.
Therefore, even if there are characteristic fluctuations or disturbances due to the surface properties of the object to be measured, it is possible to realize scanning measurement with high accuracy and constant measurement force without increasing the measurement time.

  The surface texture measuring apparatus according to the present invention includes a stylus having a contact portion that contacts the surface of the object to be measured, and a measurement force detecting unit that detects a measuring force when the contact portion contacts the surface of the object to be measured. A relative movement means for relatively moving the measurement section and the object to be measured, and a position detection means for outputting the measurement position of the measurement object by the measurement section as measurement position information. A surface texture measuring device that captures measurement position information from the position detection means while driving the relative movement means in contact with the surface of the object to be measured, and measures the surface texture of the object to be measured from the measurement position information. A scanning control means for taking in the detected measurement force from the measurement section and driving the relative movement means so that the detected measurement force substantially coincides with a target measurement force; and a detection from the measurement section Touch signal generating means that takes in a constant force and generates a touch signal when the detected measurement force matches the contact measurement force, a changeover switch means for switching between the scanning measurement mode and the touch measurement mode, and the scanning control means operates In the state where the changeover switch means is switched to the scanning measurement mode, the measurement position information from the position detection means is captured based on a predetermined condition, and in the state where the changeover switch means is switched to the touch measurement mode, Each time a touch signal is generated from the touch signal generation means, a measurement value acquisition means for acquiring measurement position information from the position detection means is provided.

  According to the present invention, since the switching switch means for switching between the scanning measurement mode and the touch measurement mode is provided, the measurement mode is switched from the scanning measurement mode to the touch measurement mode by the switching operation of the switching switch means. Then, every time a touch signal is generated from the touch signal generating means, the measurement position information from the position detecting means is taken in, so that the same effect as described above can be expected. Here, the predetermined condition means a predetermined time interval or a predetermined distance interval.

In the surface texture measuring apparatus of the present invention, it is preferable that the changeover switch unit includes a switching unit that can be switched between a scanning measurement mode and a touch measurement mode according to a user's selection according to the surface shape of the object to be measured. .
According to the present invention, the user selects the portion to be measured and the portion to be touch-measured on the surface of the object to be measured by looking at the inclination and curvature of the surface of the object to be measured. And since the user can arbitrarily switch the switching unit and select the measurement mode, for example, the device itself repeats the scanning measurement and the touch measurement, and automatically selects the optimal measurement mode while trial and error, The measurement mode can be selected quickly and accurately, and the measurement can proceed efficiently.

In the surface texture measuring apparatus of the present invention, the changeover switch means includes a switching unit that switches between a scanning measurement mode and a touch measurement mode, and a switching control unit that controls the switching unit, and the switching control unit includes the switching control unit, It is preferable to switch the switching unit based on a change in the detected measurement force detected by the measurement force detection means.
In the scanning measurement, the detected measurement force from the measurement unit becomes oscillating depending on the surface shape and material of the measurement object or the relative angle between the detection direction of the measurement force and the normal direction of the measurement object surface. In such a state, the measurement force varies, so measurement with a constant measurement force cannot be expected.
According to the present invention, based on the change in the measurement force detected by the measurement force detection means, for example, when the detected measurement force from the measurement unit vibrates and the amplitude exceeds a preset fixed width. , Because it can be switched to touch measurement, the user can switch the switching unit arbitrarily and automatically select the optimal measurement mode through trial and error. be able to.

In the surface texture measuring apparatus of the present invention, the changeover switch means includes a switching unit that switches between a scanning measurement mode and a touch measurement mode, and a switching control unit that controls the switching unit, and the switching control unit includes the switching control unit, It is preferable to switch the switching unit based on the surface shape of the object to be measured.
Here, the switching control unit switches the switching unit based on the surface shape of the object to be measured, for example, after calculating the surface shape of the object to be measured based on the measured measurement data, Examples include selecting and switching between scanning measurement and touch measurement based on the curvature of the object surface, the angle formed by the surface of the object to be measured with respect to the measurement force detection direction, and the like. Alternatively, the shape of the surface of the object to be measured may be obtained from the design data of the object to be measured, and the curvature or inclination of the surface of the object to be measured may be obtained from the design data.
According to the present invention, the surface shape of the object to be measured is analyzed, and, for example, switching control is performed to switch to touch measurement based on curvature, inclination, etc. Convenient. Then, by automatic switching, even if the surface shape cannot be measured by scanning measurement, the shape measurement can be automatically performed by touch measurement.

In the surface texture measuring apparatus of the present invention, the scanning control means includes a computing unit that computes and outputs a deviation between the detected measuring force from the measuring unit and a target measuring force, and an output signal from the computing unit with a set gain. And a gain adjusting unit that amplifies and applies to the relative moving unit, and is configured so that the set gain of the gain adjusting unit can be adjusted so that the detected measuring force from the measuring unit is in a vibrating state. It is preferable.
According to the present invention, by adjusting the setting gain of the gain adjusting means, a state in which the detected measuring force from the measuring section oscillates can be obtained, so that the relative movement position data from the position detecting means is periodically and finely timingd. Can be obtained at Therefore, higher accuracy can be achieved.

In the surface texture measuring apparatus according to the present invention, the relative movement unit includes a fine movement mechanism that slightly displaces the measurement unit and a coarse movement mechanism that displaces the measurement unit together with the fine movement mechanism more than the fine movement mechanism. The scanning control means calculates and outputs a deviation between the detected measurement force and the target measurement force from the measurement unit, and amplifies an output signal from the calculator with a set gain to the fine movement mechanism. It is preferable that the gain adjustment unit is configured so that the set gain of the gain adjustment unit can be adjusted so that the detected measurement force from the measurement unit is in a vibrating state.
Here, it is desirable that the fine movement mechanism is a drive mechanism having a high response speed. For example, a piezoelectric actuator using a piezoelectric element can be given as an example. An example of the coarse movement mechanism is an electromagnetic actuator.
According to the present invention, since the coarse movement mechanism and the coarse movement mechanism are provided, in the scanning measurement, the contact portion is quickly finely displaced by the fine movement mechanism having a quick response speed with respect to the minute unevenness on the surface of the object to be measured. It is possible to cope with a large shape change (swell or the like) on the surface of the object to be measured by a coarse movement mechanism that can tolerate a large displacement. As a result, the contact portion can be moved along the surface of the object to be measured with high accuracy and high speed.

  The surface texture measuring apparatus according to the present invention includes a stylus having a contact portion that contacts the surface of the object to be measured, and a measurement force detecting unit that detects a measuring force when the contact portion contacts the surface of the object to be measured. A surface texture measuring apparatus comprising: a moving part; a relative moving means for relatively moving the measuring part and the object to be measured; and a position detecting means for outputting a measurement position of the object to be measured by the measuring part as measurement position information. A force control loop that takes in the detected measurement force detected by the measurement unit and drives the relative movement means so that the detected measurement force substantially matches the target measurement force, and the detected measurement detected by the measurement unit A touch signal generating means for capturing a force and generating a touch signal when the detected measuring force coincides with the contact measuring force, and each time the touch signal is generated from the touch signal generating means, the position detecting hand A measurement value acquisition means for acquiring measurement position information from the measurement force, and the force control loop is configured to be set so that the detected measurement force detected by the measurement force detection means is in a vibration state. Features.

According to the present invention, the force control loop is set so that the detected measuring force detected by the measuring force detecting means is in a vibrating state in a state where the contact portion of the stylus is in contact with the surface of the object to be measured. Measure with. Then, each time the detected measurement force matches the target measurement force, a touch signal is generated, and each time the touch signal is generated, the measurement position information from the position detection unit is taken into the measurement value taking unit.
In other words, since the touch signal is generated using the vibration state of the detected measurement force, a high-speed touch signal can be generated, and measurement position information can be captured at the generation timing of the touch signal. Highly accurate measurement can be realized. In particular, since the measurement is performed using unstable vibration of the force control loop, it is possible to follow a shape that is strong and stable against disturbance, to measure an object having a steeply inclined surface, and to increase the scanning speed.
Therefore, even if there are characteristic fluctuations or disturbances due to the surface properties of the object to be measured, it is possible to realize scanning measurement with high accuracy and constant measurement force without increasing the measurement time.

In the surface texture measuring apparatus according to the present invention, the force control loop includes a computing unit that outputs a deviation between the detected measuring force detected by the measuring force detecting means and the target measuring force, and an output from the computing unit is set gain. And a gain adjusting unit that amplifies the signal to the relative moving unit and sets the gain adjusting unit of the force control loop so that the detected measuring force detected by the measuring force detecting unit is in a vibrating state. It is preferable that the gain is adjustable.
According to the present invention, by adjusting the setting gain of the gain adjusting means, a state in which the detected measuring force from the measuring section oscillates can be obtained, so that the relative movement position data from the position detecting means is periodically and finely timingd. Can be obtained at Therefore, higher accuracy can be achieved.

In the surface texture measuring apparatus according to the present invention, the relative movement unit includes a fine movement mechanism that slightly displaces the measurement unit and a coarse movement mechanism that displaces the measurement unit together with the fine movement mechanism more than the fine movement mechanism. And the force control loop outputs a deviation between the detected measurement force detected by the measurement force detection means and the target measurement force, and amplifies the output from the calculator with a set gain to thereby adjust the fine movement mechanism. And a gain adjusting means for adjusting the set gain of the gain adjusting means of the force control loop so that the detected measuring force detected by the measuring force detecting means is in a vibration state. Preferably it is.
According to the present invention, since the coarse movement mechanism and the coarse movement mechanism are provided, in the scanning measurement, the contact portion is quickly finely displaced by the fine movement mechanism having a quick response speed with respect to the minute unevenness on the surface of the object to be measured. It is possible to cope with a large shape change (swell or the like) on the surface of the object to be measured by a coarse movement mechanism that can tolerate a large displacement. As a result, the contact portion can be moved along the surface of the object to be measured with high accuracy and high speed.

In the surface texture measuring device according to the present invention, the touch signal generating means may detect when the detected measurement force from the measurement unit exceeds the contact measurement force from a value higher than the contact measurement force, and the detected measurement force from the measurement unit. It is preferable to generate a touch signal at both the timing when the contact measurement force is passed from a value lower than the contact measurement force.
According to the present invention, when the detected measurement force from the measurement unit exceeds the contact measurement force from a value higher than the contact measurement force, and the detected measurement force from the measurement unit exceeds the contact measurement force from a value lower than the contact measurement force. Since the touch signal is generated at both timings, the measurement position information from the position detection means can be acquired at a finer timing. Therefore, higher accuracy can be achieved.

In the surface texture measuring apparatus of the present invention, it is preferable that the measurement unit includes a vibration element that vibrates the stylus and a detection element that detects a vibration state of the stylus and outputs a detection signal.
According to this invention, when the contact portion comes into contact with the surface of the object to be measured and the vibration of the stylus is constrained, the vibration level becomes small. Force can be detected. In particular, since the measurement force is detected from the vibration attenuation due to the vibration being constrained, even a low measurement force can be detected with high accuracy.

[First Embodiment]
<Description of Overall Configuration of First Embodiment (FIG. 1)>
FIG. 1 is a block diagram showing a first embodiment of a surface shape measuring apparatus according to the present invention. In the description of the figure, the same components as those in FIG. 14 are denoted by the same reference numerals, and the description thereof is omitted or simplified.
The surface shape measuring apparatus according to the present embodiment includes a probe 10, a three-dimensional drive mechanism 40, and a controller 50 that controls the probe 10.
As in FIG. 14, the probe 10 includes a force sensor 1, a drive actuator 11 as a relative movement means for moving the force sensor 1 relative to the object W (advancement / retraction), and the drive actuator 11. It comprises a detector (consisting of a scale and a detection head) 12 as position detecting means for detecting a displacement amount of the force sensor 1 (that is, measurement position information of the workpiece W measured by the force sensor 1).

  The three-dimensional drive mechanism 40 constitutes a relative movement means together with the drive actuator 11 and drives the mounting portion of the probe 10 in the three-dimensional direction (X, Y, Z axis directions). The three-dimensional drive mechanism 40 is not limited to the configuration for driving the probe 10 in the three-dimensional direction, and may be a mechanism for driving the object W to be measured in the three-dimensional direction, or the probe 10 and the object W to be measured. One may be driven in at least one axial direction, and the other may be driven in the remaining axial direction.

The controller 50 includes the oscillator 21, the peak hold circuit 22, and the counter 26 as in FIG. 14, and further includes a touch signal generation unit 51, a latch counter 52, and a scanning measurement control unit 53.
The touch signal generation unit 51 (touch signal generation means) takes in a detection signal from the force sensor 1 (that is, a force sensor signal as a detection measurement force) through the peak hold circuit 22, and a contact whose detection signal is a set value. When it matches the measurement force (contact detection level), a touch signal is generated when the detection signal exceeds the contact measurement force (contact detection level) from a value higher than the contact measurement force. 52.
The latch counter 52 latches the count value of the counter 26 every time a touch signal is given from the touch signal generation unit 51, and gives it to the scanning measurement control unit 53 (measurement value fetching means 55 described later).

The scanning measurement control unit 53 includes a scanning control unit 54 and a measurement value capturing unit 55.
The scanning control means 54 takes in the detection signal from the force sensor 1 through the peak hold circuit 22 and drives the driving actuator 11 so that the detection signal substantially coincides with the target measurement force which is a set value. That is, although not shown in the figure, as in FIG. 14, the calculator 23 that calculates the deviation between the output (force sensor signal) from the peak hold circuit 22 and the target measurement force, and the output from this calculator 23 are input. And a drive amplifier 25 that drives the drive actuator 11 based on the output from the force control compensator 24.
The measured value capturing means 55 captures a detection signal (force sensor signal) from the force sensor 1 through the peak hold circuit 22 while the scanning control means 54 is in operation, and the fluctuation range of the detection signal is a predetermined constant width. It is determined whether or not the state is less than (a fluctuation range that can ignore the variation in the measured value). In a state where the fluctuation range of the detection signal is less than a predetermined fixed range, the position measurement value (measurement position information) from the counter 26 is captured at a predetermined time interval. When the detection signal from the force sensor 1 vibrates and the amplitude exceeds a preset fixed width, the position measurement value of the latch counter 52 latched every time a touch signal is generated from the touch signal generation unit 51 ( (Measurement position information).

<Measurement of constant force scanning>
A detection signal (force sensor signal) from the force sensor 1 is taken into the scanning control means 54, and the driving actuator 11 is driven by the scanning control means 54 so that the detection signal substantially matches the target measurement force (reference value). . Accordingly, the stylus 3 of the force sensor 1 is brought into contact with the object to be measured, and the surface property of the object to be measured is measured in a state where the measurement force at this time is maintained at the target measurement force.
When the constant force control is stably controlled (for example, in the state shown in FIG. 14), the deformation amount of the force sensor 1 and the object to be measured is constant, so that the measurement value can be measured with less variation.

However, when the force constant scanning control is difficult due to specific fluctuations due to the surface shape, surface properties and material of the object to be measured and disturbances input to the system, the deformation amount of the force sensor 1 and the object to be measured is stabilized. Since it changes according to the measuring force that is not, the variation of the measured value becomes large.
For example, as shown in FIG. 2, when the detection signal (force sensor signal) from the force sensor 1 reaches the target measurement force and then vibrates, the variation in the measured value increases.
Here, every time the detection signal passes the target measurement force from a value higher than the target measurement force, the touch signal generation unit 51 generates a touch signal. Then, as a result of the touch signal being given to the latch counter 52, the count value of the counter 26 is latched in the latch counter 52.

At the same time, the detection signal from the force sensor 1 is also given to the measured value capturing means 55. The measurement value fetching means 55 determines whether or not the fluctuation range of the detection signal from the force sensor 1 is in a state of being less than a predetermined fixed width. In a state where the fluctuation range of the detection signal is less than a predetermined fixed range, the position measurement value from the counter 26 is captured at predetermined time intervals. In a state where the detection signal from the force sensor 1 vibrates and the amplitude exceeds a preset fixed width, the value of the latch counter 52, that is, every time a touch signal is generated from the touch signal generator 51, the signal is latched. The position measurement value of the latch counter 52 is captured.
The scanning control means 54 operates even when the detection signal from the force sensor 1 is oscillating, so that the average value of the vibration of the detection signal from the force sensor 1 substantially matches the target measurement value. To be controlled.

Since the timing at which the touch signal is generated is when the detection signal coincides with the contact measurement force, the measurement value with a constant measurement force can be captured. That is, the measurement value is always a value when the same measurement force is generated, and a measurement value equivalent to that when the constant force control is stably controlled is obtained. As a result, it is possible to suppress variations in measured values.
In addition, since a touch signal is generated while following the shape of the object to be measured (during copying control), a touch-back operation like a conventional touch probe is unnecessary, and the measurement time can be shortened. That is, it is possible to eliminate the time loss associated with the touchback operation.
Therefore, even if there are characteristic fluctuations or disturbances due to the surface properties of the object to be measured, it is possible to realize scanning measurement with high accuracy and constant measurement force without increasing the measurement time.

In the case of the above-described method, it is a disadvantage that the generation period of the touch signal cannot be generated at an equal interval and an arbitrary period. To compensate for this, the following method can be considered.
<(1) A method of increasing the touch signal generation cycle by changing the generation condition of the touch signal>
In the method described in FIG. 2, a circuit that generates a touch signal only when the detection signal of the force sensor 1 has changed the contact detection level from a high value to a low value is used. Touch signals are generated both when the high value has passed the low value and when the low value has passed the high value. That is, the touch signal generation unit 51 of FIG. 1 is configured as a circuit that generates a touch signal at both timings described above. In this way, since the touch signal generation cycle can be increased, higher accuracy can be achieved. (FIG. 2 and FIG. 3 illustrate a case where the target measurement force of the scanning control means 54 and the contact measurement force of the touch signal generating unit 51 are the same value.)
This method can be used at the same time as the following (2) high-frequency oscillation by setting the force control loop to high gain.

<(2) Method of high-frequency oscillation by setting the force control loop to high gain>
There are mainly two reasons why the constant force scanning control is not stable.
(A) The force is disturbed by the influence of a disturbance that cannot be suppressed by force control.
(B) The force control loop has a high gain, the high frequency region becomes unstable, and an oscillation state occurs.
Although the state (b) is not preferable in normal control, when this method is used, it is possible to obtain measurement values with little variation even in such an oscillation state. In addition, in the case of oscillation by increasing the gain of the force control loop, in general, oscillation often occurs at a resonance frequency in the high frequency region possessed by the probe's mechanical system. Can achieve continuous touch.

Specifically, the scanning control unit 54 calculates the deviation between the detection signal from the force sensor 1 and the target measurement force and outputs the output signal from the calculator 23, as in FIG. It includes a force control compensator 24 as a gain adjusting means for amplifying and outputting with a set gain, and a drive amplifier 25 for driving the driving actuator 11 as a relative moving means based on the output from the force control compensator 24. Therefore, for example, when the scanning position of the force sensor 1 and the object to be measured reaches the region where the detection signal from the force sensor 1 is in a vibrating state, the measurer manually operates the force control compensator. 24 gain is adjusted or switched to high gain.
Alternatively, a circuit is provided for detecting that the detection signal from the force sensor 1 becomes oscillating and the amplitude exceeds a preset fixed width, and the gain of the force control compensator 24 is increased by a function of this circuit. Adjust or switch to.
In this way, a state in which the detection signal from the force sensor 1 oscillates is obtained, so that the position measurement value from the detector 12 can be acquired periodically and at a finer timing. Therefore, higher accuracy can be achieved.

[Second Embodiment]
<Description of Second Embodiment (FIG. 4)>
In the first embodiment, on the condition that the detection signal from the force sensor 1 exceeds a predetermined width set in advance, the value of the latch counter 52 is captured at the timing when the touch signal is generated. Then, as shown in FIG. 4, changeover switch means 56 for switching between the scanning measurement mode and the touch measurement mode is provided.
The changeover switch means 56 includes a changeover unit 56A that switches between the scanning measurement mode and the touch measurement mode according to the user's selection according to the surface shape of the object to be measured. In other words, the switching unit 56A is inserted on the measured value capturing means 55 side so as to be switchable between a terminal on the counter 26 side and a terminal on the latch counter 52 side.

  The measured value fetching means 55 is a position from the counter 26 serving as a position detecting means when the switching unit 56A of the changeover switch means 56 is switched to one side (counter 26 side) while the scanning control means 54 is operating. Measurement values (measurement position information) are taken at predetermined time intervals. In a state where the switching unit 56A is switched to the other side (latch counter 52 side), the count value of the latch counter 52, that is, the count latched by the latch counter 52 every time a touch signal is generated from the touch signal generation unit 51. Capture value.

  In this configuration, when the user discriminates the surface shape of the object to be measured and the scanning position of the force sensor 1 and the object to be measured reaches a region where the detection signal from the force sensor 1 is likely to vibrate. The switching unit 56A of the changeover switch means 56 is switched to the other side (latch counter 52 side). Then, every time a touch signal is generated from the touch signal generator 51, the measured value of the counter 26 is latched by the latch counter 52, and the measured value is captured by the measured value capturing means 55. Can be expected.

  Therefore, according to the second embodiment, the user selects the part to be measured and the part to be touch-measured on the surface of the object to be measured by looking at the inclination or curvature of the surface of the object to be measured. And since the user can arbitrarily switch the switching unit and select the measurement mode, for example, the device itself repeats the scanning measurement and the touch measurement, and automatically selects the optimal measurement mode while trial and error, The measurement mode can be selected quickly and accurately, and the measurement can proceed efficiently.

<Description of Modified Example (FIG. 5) of Second Embodiment>
In 2nd Embodiment, it is also possible to comprise so that the switching part 56A may not be switched manually by a user, but the switching part 56A may be switched automatically.
For example, in the modification shown in FIG. 5, the changeover switch means 56 includes a switching unit 56A that switches between the scanning measurement mode and the touch measurement mode, and a switching control unit 56B that controls the switching unit 56A. The switching control unit 56B switches the switching unit 56A based on a change in the force sensor signal detected by the force sensor 1 serving as a measurement force detection unit.
In the scanning measurement, the force sensor signal from the force sensor 1 becomes vibrational depending on the surface shape or material of the object to be measured. In such a state, the measurement force varies, so measurement with a constant measurement force cannot be expected. In the example illustrated in FIG. 5, the switching control unit 56 </ b> B, for example, vibrates the force sensor signal based on the change in the force sensor signal detected by the force sensor 1, and the amplitude exceeds a predetermined fixed width. In this state, the switching unit 56A is switched to the latch counter 52 side (touch measurement side), so that the user can switch the switching unit arbitrarily and automatically select the optimum measurement mode through trial and error. The selection can be made quickly and accurately, and the measurement can proceed efficiently.

Further, the changeover switch means 56 includes a switching unit 56A that switches between the scanning measurement mode and the touch measurement mode, and a switching control unit 56B that controls the switching unit 56A. It is also possible to configure to switch the switching unit 56A based on the surface shape.
For example, after calculating the surface shape of the object to be measured based on the measured data that has been measured, based on the calculated curvature of the surface of the object to be measured and the angle formed by the surface of the object to be measured with respect to the measurement force detection direction, etc. The scanning measurement and the touch measurement may be selected and switched. Alternatively, the shape of the surface of the object to be measured is obtained from the design data of the object to be measured, and the curvature or inclination of the surface of the object to be measured is obtained from this design data. You may make it switch by selecting.
In this way, the surface shape of the object to be measured is analyzed, and for example, switching control is performed to switch to touch measurement based on curvature, inclination, etc., so the user does not need to perform an operation of determining and switching, Convenient. Then, by automatic switching, even if the surface shape cannot be measured by scanning measurement, the shape measurement is automatically performed by touch measurement.

[Third Embodiment]
<Description of Third Embodiment (FIG. 6)>
In the first embodiment, initially, the scanning force constant control is performed by setting the gain of the force control compensator 24 of the scanning control means 54 to an optimum gain, and for example, the detection signal from the force sensor 1 is in a vibration state. When the scanning position of the force sensor 1 and the object to be measured reaches the area, the user manually adjusts or switches the gain of the force control compensator 24 to a high gain, or the detection signal from the force sensor 1 is oscillating. In addition, a circuit for detecting that the amplitude exceeds a preset fixed width is provided, and the gain of the force control compensator 24 is adjusted or switched to a high gain by the function of this circuit.

  In the third embodiment, as shown in FIG. 6, a force sensor signal (detected measurement force) detected by a force sensor 1 as a measurement unit is captured, and the force sensor signal is used for driving so as to coincide with a target measurement force. A force control loop 28 for driving the actuator 11 (relative movement means) and a force sensor signal detected by the force sensor 1 are captured, and a touch signal is generated when the force sensor signal matches the contact measurement force. Unit 51 and a measurement value capturing means 55 for capturing measurement position information from the counter 26 each time a touch signal is generated from the touch signal generation unit 51, the force control loop 28 is in an unstable state from the beginning. It is configured so that the copying measurement can be performed.

The force control loop 28 outputs a deviation between the force sensor signal detected by the force sensor 1 (measurement force detection means) and the target measurement force, similarly to the scanning control means 54 of FIG. 1 and the force control loop of FIG. A calculator 23, a force control compensator 24 as a gain adjusting means for amplifying and outputting the output from the calculator 23 with a set gain, and amplifying the output of the force control compensator 24 to the drive actuator 11 The drive amplifier 25 is provided.
The force control loop 28 is configured to be set so that the force sensor signal detected by the force sensor 1 is in a vibration state. That is, the setting gain of the force control compensator 24 of the force control loop 28 is configured to be adjustable so that the force sensor signal is in a vibration state.

According to the third embodiment, the force control loop 28 is set so that the force sensor signal detected by the force sensor 1 is in a vibrating state when the contact portion of the force sensor 1 is in contact with the surface of the object to be measured. In this state, the scanning measurement is performed. Then, every time the force sensor signal matches the contact measurement force, a touch signal is generated from the touch signal generation unit 51, and each time a touch signal is generated, the value of the counter 26 is latched by the latch counter 52 and the measured value is acquired. It is taken into the insertion means 55.
That is, since the touch signal is generated using the vibration state of the force sensor signal, a high-speed touch signal can be generated, and measurement position information can be captured at the generation timing of the touch signal. Highly accurate measurement can be realized. In particular, since the measurement is performed using the unstable vibration of the force control loop 28, it is possible to follow a shape that is strong and stable against disturbance, to measure an object having a steeply inclined surface, and to increase the scanning speed.
Therefore, even if there are characteristic fluctuations or disturbances due to the surface properties of the object to be measured, it is possible to realize scanning measurement with high accuracy and constant measurement force without increasing the measurement time.
Since the force control loop 28 is operating in a state where the detection signal from the force sensor 1 is oscillating, control is performed so that the average value of the vibration of the detection signal of the force sensor 1 substantially matches the target measurement value. Is done.

[Fourth Embodiment]
<Description of Fourth Embodiment (FIG. 7)>
In the fourth embodiment, in contrast to the modification of the second embodiment (FIG. 5), the driving actuator 11 as the relative movement means is a fine movement actuator serving as a fine movement mechanism that minutely displaces the force sensor 1 (measurement unit). 11A and a coarse movement part actuator 11B as a coarse movement mechanism that displaces the force sensor 1 more than the fine movement part actuator 11A together with the fine movement part actuator 11A.
The fine movement actuator 11A is preferably a drive mechanism with a fast response speed, and for example, a piezoelectric actuator using a piezoelectric element can be used. An electromagnetic actuator or the like can be used as the coarse movement actuator 11B.

In the same manner as described above, the scanning control means 54 constituting the force control loop amplifies the computing unit 23, the force control compensator 24, and the output of the force control compensator 24 to finely adjust the actuator 11A and the coarse actuator. And a drive amplifier 25 applied to 11B, and the set gain of the force control compensator 24 constituting the force control loop is adjustable so that the force sensor signal is in a vibration state.
In the present embodiment, coarse movement control means 57 that controls the driving of the coarse movement actuator 11B is provided separately following the change in the shape of the surface of the object to be measured.

  In the fourth embodiment, since the fine movement actuator 11A and the coarse movement actuator 11B are provided, in the scanning measurement, the contact portion is moved by the fine movement actuator 11A having a high response speed with respect to minute irregularities on the surface of the object to be measured. The coarse movement actuator 11 </ b> B can be quickly displaced minutely and can cope with a large shape change (swell or the like) on the surface of the object to be measured. As a result, the contact portion can be moved along the surface of the object to be measured with high accuracy and high speed.

<Description of Modified Example (FIG. 8) of Fourth Embodiment>
In the fourth embodiment, the driving actuator 11 includes the fine movement actuator 11A and the coarse movement actuator 11B. However, the coarse movement actuator 11B can be replaced by the three-dimensional drive mechanism 40.
That is, as shown in FIG. 8, the coarse movement actuator 11 </ b> B may be omitted, and the shape tracking may be performed by the three-dimensional drive mechanism 40 instead. In this case, the position of the force sensor 1 is obtained by adding the value of the detector 12 (displacement amount of the force sensor 1) taken into the measurement value taking means 55 and the amount of movement moved by the three-dimensional drive mechanism. What should I do?

  The configuration of the fourth embodiment, that is, the point that the drive actuator 11 is composed of the fine movement actuator 11A and the coarse movement actuator 11B is applied to the drive actuator 11 of the third embodiment. Is also possible.

<Description of modification>
The present invention is not limited to the above-described embodiment, and modifications and improvements within the scope that can achieve the object of the present invention are included in the present invention.
In the above-described embodiment, the base 2 and the stylus 3 of the force sensor 1 are integrally formed. That is, the base 2 and the stylus 3 may be configured separately and the stylus 3 may be bonded and fixed to the base 2.
In the above embodiment, the stylus 3 is vibrated in the axial direction. However, the present invention is not limited to this, and the stylus 3 may be vibrated in a direction intersecting the axis of the stylus 3.
Furthermore, in each embodiment, the target measurement force in the scanning control unit, the target measurement force in the force control loop, and the contact measurement force in the touch signal generation unit are individually described. However, the same measurement force may be used as a value. Absent.
Further, in each embodiment, the example in which the position measurement value (measurement position information) from the counter 26 is fetched at a predetermined time interval is shown. However, the present invention is not limited to this, and the combination of the predetermined position interval or the predetermined time interval and the predetermined distance interval is used. You may capture position measurements.
Furthermore, in the first embodiment (FIG. 1), the example including the driving actuator 11 has been described. However, the present invention is not limited thereto, and the driving actuator 11 may not be provided. In this case, the scanning control means 54 controls the three-dimensional drive mechanism 40 (X, Y, Z axes), and the measured value capturing means 55 is a displacement (for example, X, Y, Z axes) of each axis of the three-dimensional drive mechanism. ) And the position measurement value from the counter 26 or the position measurement value of the latch counter 52 is taken in as a measurement value.
Moreover, although the three-dimensional drive mechanism 40 shown in each embodiment showed what controls the three orthogonal axes of the X, Y, and Z axes, it is not limited to this, and is a two-dimensional drive mechanism or a one-dimensional drive mechanism. In addition, not only the linear motion mechanism but also a rotation mechanism may be included. In short, it is sufficient that the probe 10 and the object to be measured can be driven relative to each other and the driving amount can be detected.

In each of the above embodiments, a stylus that vibrates in the axial direction is used. However, the stylus according to the present invention is not limited to this, and for example, has a structure as shown in FIG. Also good.
The stylus 90 has an elastic lever 91 whose longitudinal direction is arranged substantially orthogonal to the operation direction of the drive actuator 11 (or the fine movement actuator 11A and the coarse movement actuator 11B) and is elastically deformable in the direction along the operation direction. Via the movable part for driving these actuators. When such a stylus is brought into contact with the surface of the object to be measured, the measuring force acting between the object to be measured and the stylus 90 causes the elastic lever 91 to be elastically deformed. Therefore, by detecting the amount of elastic deformation of the elastic lever 91, it is possible to know the change in measuring force. The detecting means for detecting the amount of elastic deformation of the elastic lever 91 may be constituted by, for example, a strain sensor. The detecting means irradiates the upper surface of the elastic lever 91 with the laser beam 92 and the like, and also reflects the reflected light 93 from this upper surface. In addition, a detector 94 that detects the amount of elastic deformation of the elastic lever 91 may be used.

  The present invention can be applied to a surface roughness measuring machine, a shape measuring machine, a contour measuring machine, a roundness measuring machine, a three-dimensional measuring machine, and the like that measure the surface roughness of an object to be measured. In particular, it is suitable for measuring fine shapes.

The block diagram which shows 1st Embodiment of the surface shape measuring apparatus which concerns on this invention. The figure which shows the touch signal at the time of force sensor signal vibration in 1st Embodiment. The figure which shows the touch signal at the time of force sensor signal vibration in 1st Embodiment. The block diagram which shows 2nd Embodiment of the surface shape measuring apparatus which concerns on this invention. The block diagram which shows the modification of 2nd Embodiment. The block diagram which shows 3rd Embodiment of the surface shape measuring apparatus which concerns on this invention. The block diagram which shows 4th Embodiment of the surface shape measuring apparatus which concerns on this invention. The block diagram which shows the modification of 4th Embodiment. The perspective view which shows the modification of a measurement part. The disassembled perspective view which shows the structure of a force sensor. The figure which shows the vibration signal and detection signal which are given to a force sensor. The figure which shows the change of a detection signal when a force sensor contacts a to-be-measured object. The figure which shows the relationship between the attenuation factor of the detection signal of a force sensor, and measurement force. The block diagram which shows the shape measurement system using a force sensor. The figure which shows the change of a force sensor signal in the system of FIG. The figure which shows the relationship between a force sensor signal, a contact detection level, and a touch signal in the system of FIG. The figure which shows a mode when the contact detection level is fluctuated up and down in the system of FIG. The figure which shows a mode when a force detection signal will be in a vibration state in the system provided with the scanning measurement mode and the touch measurement mode.

Explanation of symbols

1 ... Excitation force sensor (measuring unit)
DESCRIPTION OF SYMBOLS 3 ... Stylus 4,5 ... Excitation element and detection element which comprise measurement force detection means 10 ... Probe 11 ... Drive actuator (relative movement means)
12 ... Detector (position detection means)
24. Force control compensator (gain adjustment means)
DESCRIPTION OF SYMBOLS 26 ... Counter 28 ... Force control loop 50 ... Controller 51 ... Touch signal generation part 52 ... Latch counter 53 ... Copying measurement control part 54 ... Copying control means 55 ... Measurement value taking-in means 56 ... Changeover switch means 56A ... Switching part 56B ... Switching control unit.

Claims (12)

A stylus having a contact portion that contacts the surface of the object to be measured, a measuring unit having a measuring force detecting means for detecting a measuring force when the contact portion contacts the surface of the object to be measured, and the measuring unit and the object to be measured A state in which the contact portion of the stylus is brought into contact with the surface of the object to be measured, including relative movement means for relatively moving the object, and position detection means for outputting the measurement position of the object to be measured by the measurement unit as measurement position information A surface texture measuring device that captures measurement position information from the position detection means while driving the relative movement means, and measures the surface texture of the object to be measured from the measurement position information,
A scanning control unit that takes in the detected measurement force from the measurement unit and drives the relative movement unit so that the detected measurement force substantially matches the target measurement force;
Touch signal generating means for capturing a detection measurement force from the measurement unit and generating a touch signal when the detection measurement force matches the contact measurement force;
While the scanning control unit is operating, in a state where the fluctuation range of the detection measurement force from the measurement unit is less than a predetermined fixed range, the measurement position information from the position detection unit is captured based on a predetermined condition, and the measurement is performed. In a state in which the detection measurement force from the part vibrates and the amplitude exceeds a predetermined fixed width, every time a touch signal is generated from the touch signal generation unit, measurement position information from the position detection unit is captured. A surface texture measuring device comprising a value capturing means. A stylus having a contact portion that contacts the surface of the object to be measured, a measuring unit having a measuring force detecting means for detecting a measuring force when the contact portion contacts the surface of the object to be measured, and the measuring unit and the object to be measured A state in which the contact portion of the stylus is brought into contact with the surface of the object to be measured, including relative movement means for relatively moving the object, and position detection means for outputting the measurement position of the object to be measured by the measurement unit as measurement position information A surface texture measuring device that captures measurement position information from the position detection means while driving the relative movement means, and measures the surface texture of the object to be measured from the measurement position information,
A scanning control unit that takes in the detected measurement force from the measurement unit and drives the relative movement unit so that the detected measurement force substantially matches the target measurement force;
Touch signal generating means for capturing a detection measurement force from the measurement unit and generating a touch signal when the detection measurement force matches the contact measurement force;
Changeover switch means for switching between the scanning measurement mode and the touch measurement mode;
In a state in which the scanning control unit is in operation and the changeover switch unit is switched to the scanning measurement mode, the measurement position information from the position detection unit is captured based on a predetermined condition, and the switching switch unit is set to the touch measurement mode. In the switched state, the surface texture measuring device includes a measurement value capturing unit that captures measurement position information from the position detection unit each time a touch signal is generated from the touch signal generation unit. . In the surface texture measuring device according to claim 2,
The surface texture measuring apparatus according to claim 1, wherein the change-over switch means includes a switching unit that can be switched between a scanning measurement mode and a touch measurement mode according to a user's selection according to the surface shape of the object to be measured. In the surface texture measuring device according to claim 2,
The changeover switch means includes a switching unit that switches between the scanning measurement mode and the touch measurement mode, and a switching control unit that controls the switching unit,
The surface texture measuring device according to claim 1, wherein the switching control unit switches the switching unit based on a change in the detected measuring force detected by the measuring force detecting unit. In the surface texture measuring device according to claim 2,
The changeover switch means includes a switching unit that switches between the scanning measurement mode and the touch measurement mode, and a switching control unit that controls the switching unit,
The surface texture measuring device, wherein the switching control unit switches the switching unit based on a surface shape of the object to be measured. In the surface texture measuring device according to any one of claims 1 to 5,
The scanning control means computes and outputs a deviation between the detected measurement force from the measurement unit and the target measurement force, and amplifies an output signal from the computation unit with a set gain, and gives the relative movement means And a gain adjusting means,
The surface texture measuring apparatus, wherein the set gain of the gain adjusting means is adjustable so that the detected measuring force from the measuring unit is in a vibrating state. In the surface texture measuring device according to any one of claims 1 to 6,
The relative movement means includes a fine movement mechanism that finely displaces the measurement unit, and a coarse movement mechanism that displaces the measurement unit larger than the fine movement mechanism together with the fine movement mechanism.
The scanning control means is a calculator that calculates and outputs a deviation between the detected measurement force and the target measurement force from the measurement unit, and a gain that amplifies an output signal from the calculator with a set gain and gives the fine movement mechanism And adjusting means,
The surface texture measuring apparatus, wherein the set gain of the gain adjusting means is adjustable so that the detected measuring force from the measuring unit is in a vibrating state. A stylus having a contact portion that contacts the surface of the object to be measured, a measuring unit having a measuring force detecting means for detecting a measuring force when the contact portion contacts the surface of the object to be measured, and the measuring unit and the object to be measured A surface texture measuring device comprising: a relative movement unit that relatively moves an object; and a position detection unit that outputs a measurement position of the measurement object by the measurement unit as measurement position information,
A force control loop that takes in the measurement force detected by the measurement unit and drives the relative movement means so that the detected measurement force substantially matches the target measurement force;
Touch signal generating means for capturing the detected measurement force detected by the measurement unit and generating a touch signal when the detected measurement force matches the contact measurement force;
Each time a touch signal is generated from the touch signal generation means, the measurement value acquisition means for acquiring measurement position information from the position detection means,
The surface texture measuring apparatus, wherein the force control loop is settable so that the detected measuring force detected by the measuring force detecting means is in a vibrating state. In the surface texture measuring device according to claim 8,
The force control loop outputs a deviation between the detected measurement force detected by the measurement force detection means and the target measurement force, and amplifies the output from the calculation unit with a set gain to the relative movement means. And a gain adjusting means for giving,
The surface texture measuring apparatus, wherein the set gain of the gain adjusting means of the force control loop is adjustable so that the detected measuring force detected by the measuring force detecting means is in a vibration state. In the surface texture measuring device according to claim 8,
The relative movement means includes a fine movement mechanism that finely displaces the measurement unit, and a coarse movement mechanism that displaces the measurement unit larger than the fine movement mechanism together with the fine movement mechanism.
The force control loop outputs a deviation between a detected measurement force detected by the measurement force detection means and a target measurement force, and amplifies an output from the calculator with a set gain and gives the fine movement mechanism And a gain adjusting means,
The surface texture measuring apparatus, wherein the set gain of the gain adjusting means of the force control loop is adjustable so that the detected measuring force detected by the measuring force detecting means is in a vibration state. In the surface texture measuring device according to any one of claims 1 to 10,
The touch signal generation means is configured to perform contact measurement when the detected measurement force from the measurement unit exceeds the contact measurement force from a value higher than the contact measurement force and when the detected measurement force from the measurement unit is lower than the contact measurement force. A surface texture measuring device that generates a touch signal at both the timing when the force is exceeded. In the surface texture measuring device according to any one of claims 1 to 11,
The surface property measuring apparatus, wherein the measurement unit includes a vibration element that vibrates the stylus and a detection element that detects a vibration state of the stylus and outputs a detection signal.

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