JPH0748043B2 - Dimension measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention reciprocates a measuring element by an electric motor, detects the amount of movement of the measuring element when the measuring element contacts an object to be measured, and The present invention relates to a size measuring device that measures the size and the like of a measurement object.

[Background technology]

As a dimension measuring device having a relatively large measuring range and capable of easily measuring the dimension of an object to be measured, for example, Japanese Patent Publication No.
As shown in Japanese Patent Publication No. 58-10681, Japanese Patent Publication No. 59-19283, etc., the moving amount of the tracing stylus is detected by moving the tracing stylus by an electric motor and bringing it into contact with the surface of the object to be measured with a predetermined pressure. A type of dimension measuring device is known.

In such a type of conventional dimension measuring device, an electric motor is supported by a support body that is a main body, and a nut member is screwed onto a feed screw shaft that rotates in conjunction with the electric motor, and a nut member is supported on the nut member. A spindle, which is reciprocally supported by the body and has a measuring element at one end, is mounted so as to be engageable and disengageable. The spindle is provided with a measuring pressure by a spring or its own weight provided between the spindle and the nut member. Along with
Detecting means for detecting relative movement of the spindle with respect to the nut member as an on-off type is provided, and further displacement detecting means for detecting the amount of movement of the spindle is provided between the spindle and the support. .

[Problems to be Solved by the Invention]

However, since the conventional dimension measuring device detects the amount of movement of the spindle while stopping the electric motor based on the on-off output of the detection means, only the measured value at one point of the measured object can be obtained. Therefore, there is a problem that it is impossible to measure a plurality of points or continuous points such as unevenness on the surface of the object to be measured. Therefore, it is conceivable that the detecting means is of an analog type, and the electric motor is drive-controlled based on the analog output to move the tracing stylus following the surface of the object to be measured.

However, in the conventional dimension measuring device, the spindle is directly supported by the support so as to be reciprocally movable, and the solid frictional force between the spindle and the support is inevitably large. Therefore, if you simply control the drive of the electric motor,
There is a problem that the measurement pressure is largely different between when the spindle is moved forward and when the spindle is moved backward, and a so-called back-and-forth error occurs in the measurement value, and high-precision measurement cannot be performed.

An object of the present invention is to provide a dimension measuring device that can measure irregularities and the like on the surface of an object to be measured with high accuracy.

[Means for Solving the Problems]

According to the present invention, a parallel link mechanism is provided on a slider that can reciprocate in conjunction with an electric motor, a probe is provided at one end of the parallel link mechanism, and the probe rotates when it comes into contact with an object to be measured. A dimension measuring device that detects the amount of rotation of a parallel link and drives and controls an electric motor so that the amount of rotation is constant, thereby reducing the frictional force associated with the movement of the probe and enabling continuous measurement. .

Specifically, according to the present invention, a support, a slider movably held up and down by the support, an electric motor and a power transmission means for reciprocating the slider along the support, and a predetermined vertical direction. The first and second link members, which are arranged at intervals and each of which has an intermediate portion rotatably supported by the slider, and the slider which is rotatably supported by one end portions of both the link members. A parallel link mechanism configured to include a holder that can move in parallel with the probe, a probe provided at one end of the holder, and the probe being biased downward by a predetermined bias force on the holder side. Biasing means provided, rotation angle detection means for detecting the rotation angles of the first and second link members, and a main scale provided on one of the holder and the support and on the other. Displacement Displacement detecting means including an output device for detecting the vertical displacement of the probe, and drive control of the electric motor based on the output of the rotation angle detecting means so that the link member has a predetermined angle. A dimension measuring apparatus comprising: a control circuit.

[Action]

In the above configuration, the electric motor is driven in advance, the slider is raised through the power transmission means, and the probe is moved by the predetermined amount with respect to the object mounting table through the first and second link members and the holder. To raise.

Then, when the electric motor is reversed in the measurement mode to lower the slider, the tracing stylus also descends, and the tracing stylus comes into contact with the object to be measured on the table and tries to stop at that position.
On the other hand, since the slider is still moving in the descending direction at the moment of attempting to stop, the holder provided with the tracing stylus and the slider move relative to each other in the up-down direction, and the first and second link members are not moved. The rotation angle is detected by the rotation angle detection means, and the output signal of the rotation angle detection means controls the drive of the electric motor so that the rotation angles of both link members are constant. At this time, the position of the tracing stylus is detected by the displacement detecting means, and the dimension of the measured object is measured. Therefore,
When the surface height of the object to be measured changes continuously, the motor moves the slider up and down to keep the rotation angle of both link members constant, and moves the probe to follow the surface of the object to be measured. .

In the above-mentioned measurement, the measuring element and the holder for holding the measuring element are not directly slidably supported by the supporting body as in the conventional case, but are freely rotatable by the slider via the first and second link members. The friction torque acting on the rotation centers of both link members and the torque that tries to rotate both link members has an effect that the arm length from the rotation center to the probe is long. It can be made extremely small, and the friction torque hardly hinders the displacement of the probe with respect to the slider. Therefore, when the tracing stylus is moved forward, the measured pressure when the tracing stylus is moved back is substantially constant, and the above-mentioned back-and-forth error does not occur.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

1 to 5 are a longitudinal sectional view, a front view, a side view, a plan view and a partially omitted exploded perspective view showing an essential part of this embodiment, and FIG. VI-VI line cross section of
FIG. 7 shows a circuit diagram of this embodiment, and FIG. 8 shows a perspective view of the entire structure of a measuring machine incorporating this embodiment.

In FIG. 8, a measuring machine 10 is provided with a base 11, and a column 12 standing on the base 11 is integrally formed with a head portion 13 protruding to one side. A digital display 14 and a display lamp 15 are provided on the front surface of the head portion 13, and a dimension measuring device 20 according to the present invention is incorporated inside. A table 16 on which the object to be measured 5 is placed is provided on the upper surface of the base 11, and an operation panel 17 equipped with a power source and other various switches is incorporated on the front surface.

1 to 6, the dimension measuring device 20 is a support.
It has 21. The support 21 includes a bottom plate 22 and the bottom plate 22.
The guide member 23 has a substantially prismatic shape and is provided upright at substantially the center of the guide member 22, a top plate 24 fixed to the upper end of the guide member 23, and a side plate 25 protruding from one end of the bottom plate 22.

A rectangular tube-shaped slider 27 is supported on the guide member 23 so as to be vertically slidable along the guide member 23. The slider 27 is powered by a motor 28 fixed to a top plate 24.
It is designed to be driven in the vertical direction via 31. The power transmission means 31 has a drive gear 32 fixed to the output shaft 29 of the electric motor 28, a driven gear 33 meshed with the drive gear 32 fixed at one end, and is rotated between the top plate 24 and the bottom plate 22. A feed screw shaft 34 supported freely and immovably in the vertical direction,
The nut member 35 is screwed onto the feed screw shaft 34 and fixed to the slider 27.

As shown in FIGS. 5 and 6, the front and rear side surfaces of the slider 27 are vertically spaced apart by a predetermined distance from each other, and the apex shafts 41 and 42, respectively.
And a first link member formed of two elongated plates in the front and rear through the bearings 43 and 44, respectively, on the pointed shafts 41 and 42.
The center portions of the 51 and the second link member 52 are rotatably supported. At this time, the pivot shaft bearings 45 and 46 are constituted by the pointed shafts 41 and 42 and the bearings 43 and 44, respectively.

The first link member composed of a pair of front and rear plates, respectively.
Between the 51 and the second link member 52, at one end (front end) slightly inside and at the other end (rear end) thereof, a connecting member, respectively.
It is connected by 53 and 54, and the front and rear plates are integrally rotated.

A holder 55 is rotatably supported between the front end portions of the first link member 51 and the second link member 52 via pivot bearings 56 and 57, respectively. These pivot bearings
56 and 57 are composed of pointed shafts 58 and 59, both ends of which are protruded from the holder 55 at a predetermined distance, and bearings 61 and 62, which are attached to the first and second link members 51 and 52, respectively. ing. Also,
The upper and lower cusps 58 and 59 are the cusps 41 and 41 protruding from the slider 27.
The interval is equal to 42, so that the first and second link members 51, 52, the slider 27, and the holder 55 constitute a parallel link mechanism 65.

The lower end of the holder 55 is loosely fitted in a through hole 22A formed in the bottom plate 22 of the support 21, and a probe 67 is attached to the lower end via a spindle 66 penetrating the through hole 22A. Has been. On the other hand, a notch provided on one side of the holder 55
A main scale 71 having a predetermined scale is vertically installed and bonded to 55A. This main scale 71
The scale surface 71A, the spindle 66, and the axis of the probe 67 are arranged on a straight line. On the side plate 25 at a position facing the main scale 71, an index scale 72 having a predetermined scale and a light source not shown, a light receiving element, and a displacement detector 73 incorporating a detection circuit are provided.
The support 21 and the main scale 71, that is, the displacement of the probe 67 with respect to the support 21 can be detected. Here, the main scale 71 and the displacement detector 73 are used to detect a displacement detector 74 for detecting the vertical displacement of the probe 67.
Is configured.

Connecting member 54 for connecting the rear end side of the second link member 52
Is a disc-shaped weight as a biasing means via a screw shaft 76.
77 is rotatably screwed, and the position of the weight 77 with respect to the screw shaft 76 is fixed by a lock nut 78.

The position of the weight 77 is provided on the weight of the holder 55, the main scale 71, the spindle 66, the probe 67, etc., which are connected to one end of the first and second link members 51, 52, that is, the slider 27. The moment that urges the first and second link members 51 and 52 counterclockwise in FIGS. 1 and 2 about the sharp shafts 41 and 42, and the weight of the screw shaft 76, the weight 77, the lock nut 78, and the like. Is set at a position where the moment for rotating the first and second link members 51, 52 in the clockwise direction based on the above is almost balanced, and the moment on the holder 55 side becomes slightly large. That is, the weight 77 is set at a position where the tracing stylus 67 is biased downward with a slight biasing force. Therefore, first,
The second link members 51, 52 are normally urged to rotate counterclockwise in the figure, and the tracing stylus 67 is always about to move downward. 51,52
Is restricted from rotating in either the clockwise or counterclockwise direction by a rotation restricting means 79 composed of L-shaped brackets provided on the front and rear side walls of the slider 27, so that the probe 67 side is slightly lowered. Is stopped while being in contact with the rotation restricting means 79. At this time, the gap between the rotation restricting means 79 and the first and second link members 51, 52 is set to a slight amount, and the inclination angles of the first and second link members 51, 52 are also set to a slight angle. It is said that.

A substantially T-shaped actuating piece 81 is fixed to one of the first link members 51, that is, the plate member on the front side in FIGS. 2 and 5, in correspondence with the position of the bearing 43, and the lower end of the actuating piece 81 is It extends to the vicinity of the second link member 52 and is bent outward, and a slit 82 is formed at this bent portion. At a position facing the operating piece 81, a bottom plate is provided between the bottom plate 22 and the top plate 24.
The support shaft 85 is rotatably supported by bearing stones 84 that are respectively screwed into the top plate 24 and the top plate 24 and have recesses 83 formed in the facing surfaces. An operating shaft 87 is fixed to the supporting shaft 85 in parallel with the supporting shaft 85 via a pair of upper and lower operating shaft holding members 86,
The operating shaft 87 is engaged with the slit 82 of the operating piece 81. Therefore, when the operating piece 81 rotates and is tilted integrally with the first link member 51, the operating shaft 87 turns about the support shaft 85, and accordingly, the operating shaft holding member 86 and the support shaft 85 also. It is designed to rotate. Further, the lower operating shaft holding member 86
A shutter plate 88 is fixed to. This shutter plate 88
Is inserted in a U-shaped groove of a U-shaped photo interrupter 89 having a light emitting portion and a light receiving portion, and the amount of light emitted from the light emitting portion to the light receiving portion can be changed.
The photo interrupter 89 is attached to a holding plate 91 provided upright on the bottom plate 22.

Further, as shown in FIG. 7, the photo interrupter 89 includes an angle detection circuit 93 for detecting the rotation angles of the first and second link members 51, 52 based on the change in the amount of light received by the photo interrupter 89. Are connected. This angle detection circuit 93
Of the displacement detector 73 is input to the control circuit 102, and the output signal from the displacement detector 73 is also input to this control circuit. The control circuit 102 is also connected to the digital display 14, the display lamp 15, the operation panel 17 and the drive circuit 103 for the electric motor 28, and according to the operation of the operation panel 17, the display lamp 15 is turned on and the displacement detector 73 is connected. The displacement detected by is displayed on the digital display 14, and the electric motor 28 is drive-controlled by signals from the operation panel 17 and the angle detection circuit 93. The control of the electric motor 28 is controlled so that the rotation angles of the first and second link members 51 and 52 are substantially constant in the measurement mode. Here, the control circuit 102, the angle detection circuit 93, and the drive circuit 103 constitute control means 101. The control means 101 is provided in the head portion 13 of the measuring machine 10 in FIG. It is located behind.

Further, the operating piece 81, the bearing stone 84, the support shaft 85, the operating shaft holding member 86, the operating shaft 87, the shutter plate 88, the photo interrupter 89.
The holding plate 91 and the angle detection circuit 93 constitute a rotation angle detection means 95 for detecting the rotation angles of the first and second link members 51 and 52.

Reference numeral 38 is a light shielding plate provided on the back side of the main scale 71.

Next, the operation of this embodiment will be described.

At the start of the measurement, the table of the measuring machine 10 shown in FIG.
Without placing the object to be measured 5 on 16, the start switch of the operation panel 17 is pushed to drive the electric motor 28 via the control means 101. By driving this electric motor 28, the power transmission means 31
The slider 27 is lifted via the
The tracing stylus 67 is lifted by a predetermined amount via the link members 51, 52, the holder 55, and the spindle 66 and stopped.

Next, when the electric motor 28 is driven in the reverse direction, the tracing stylus 67 is lowered and brought into contact with the upper surface of the table 16 to be stopped, and the holder 55 is also stopped via the spindle 66. On the other hand, at the moment when the contact point 67 contacts the table 16, the slider 27 moves to the electric motor 28.
Is driven in the descending direction by the
55 and the slider 27 move relative to each other in the vertical direction. As a result, the first and second link members 51, 52 are attached to the pivot bearings 45, 46.
It will rotate and tilt in the clockwise direction centering around.
Along with the inclination of the first link member 51, the operating piece 81 also rotates clockwise and inclines, and the inclination of the operating piece 81 becomes a slit.
It is transmitted to the actuating shaft 87 via 82, and the shutter plate 88 together with the actuating shaft holding member 86 is driven counterclockwise around the support shaft 85 as seen in a plan view. With the rotation of the shutter plate 88, the amount of received light of the photo interrupter 89 changes, and the change in the amount of received light detected by the photo interrupter 89 is converted into an electric signal and taken into the angle detection circuit 93 to calculate the angle. Then, the output signal is output to the control circuit 102. The control circuit 102 compares a preset reference signal with the angle signal, and controls the drive of the electric motor 28 via the drive circuit 103 so that the angle signal becomes substantially equal to the reference signal. That is, when the angle signal differs from the reference signal, the electric motor 28 is driven so that the angle difference becomes smaller. By driving the electric motor 28, the slider is moved through the power transmission means 31.
27 is driven up or down, and the slider 27
The holder 55 and the tracing stylus 67 are displaced relative to each other to change the inclination angles of the first and second link members 51, 52, and the angle signal is detected by the angle detection circuit 93 in the same manner as described above.
It is output to 102, where both signals are compared, and thereafter, this operation is repeated until both signals become substantially equal.

The vertical displacement of the probe 67, that is, the holder 55, is detected by the main scale 71 and the displacement detector 73, and signals from the displacement detector 73 are sequentially displayed on the digital display 14 via the control means 101. ing. At this time, an electric signal based on the change in the amount of light received from the photo interrupter 89 of the rotation detecting means 92 is input, and when the electric signal becomes equal to or lower than the reference signal, the electric motor 28 is operated by the action of the control circuit 102 as described above. The display value of the digital display 14 changes sequentially, but when the measured point is one point, the drive of the electric motor 28 is stopped in a state where the both signals substantially match,
The displayed value becomes constant at a predetermined value. At the start of the measurement, the DUT 5 is not placed on the table 16. Therefore, when the display value becomes constant at the position where the probe 67 hits the upper surface of the table 16, the operation panel Press the reset button 17 and set the display on the digital display 14 to zero.

Next, the raising switch of the operation panel 17 is pressed to drive the electric motor 28 to raise the probe 67 by a predetermined amount, that is, the range in which the DUT 5 can be inserted and stop. In this state, when the DUT 5 is placed on the table 16 and the measurement switch of the operation panel 17 is operated to the measurement mode, the tracing stylus 67 is driven in the descending direction, and the tracing stylus 67 is placed on the upper surface of the DUT 5. Abut. At this time, similarly to the above, the holder 55 and the slider 27 are relatively displaced in the vertical direction, the first and second link members 51 and 52 are rotated, and the rotation angle detection means 95 is provided via the operating piece 81. This rotation is detected by. Upon detection of this rotation, the electric motor 28 is driven so that the rotation angles of the first and second link members 51 and 52 are constant, and the digital display 14 displays the constant rotation angle. Measuring element 67 from the displacement detecting means 74
The display value of the displacement of is the height dimension of the measured object.

By the way, when there is unevenness on the surface to be measured of the DUT 5 and it is also desired to measure the dimensions of these unevenness, the DUT 5 is moved in a predetermined direction on the table 16. With this movement, the tracing stylus 67 is displaced in the vertical direction, and the first and second link members 51, 5
Since the rotation angle of 2 changes, the electric motor 28 is driven following this change, which enables continuous measurement according to the unevenness of the surface to be measured. At this time, if the surface to be measured is convex like the outer peripheral surface of the outer ring of the bearing, the measured value decreases before and after the peak of the diameter part of the bearing, so hold this peak value appropriately. By holding in the circuit, the true diameter can be measured. On the other hand, when the surface to be measured is a concave surface, the depth of the concave surface can be measured by holding the minimum value, and shapes other than these can be measured appropriately, and the maximum and minimum values of the continuous surface to be measured can also be measured. It is also possible to continuously output and draw a diagram.

In the measurement of the height dimension of the DUT 5 as described above, the rotation of the first and second link members 51 and 52 is extremely smoothly performed. That is, in order to displace the tracing stylus 67 with respect to the slider 27, in addition to the turning force (biasing force) based on the difference between the weight on the holder 55 side and the weight on the weight 77 side, each pivot bearing 4
The force that can resist the friction torque at 5,46,56,57 is
These friction torques are extremely small in the present embodiment, though they need to be applied to 67. More specifically, as shown in FIG. 6, the distance l from the rotation center of each link member 51, 52 with respect to the slider 27 to the position where the frictional force acting between the slider 27 and each link member 51, 52 acts. ₁ and the distance l ₂ from the center of rotation of each link member 51, 52 with respect to the holder 55 to the position where the frictional force acting between the holder 55 and each link member 51, 52 is equal, and these two It is extremely smaller than the distance L between the centers of rotation. Therefore, due to the lever action, the force applied to the probe 67 beyond the biasing force based on the weight difference, that is, the first and second link members 51 acting on both pivots of the link members 51, 52. ,
Even if the moment to rotate 52 is extremely small,
This is because it is possible to easily obtain a moment that overcomes the friction torque in each of the pivot bearings 45, 46, 56, 57.
In other words, the contact force of the probe 67 with respect to the DUT 5, that is, the measurement pressure can be made extremely small.

Further, in rotating the first and second link members 51, 52, a force for rotating the operating shaft 87 for detecting the rotation angle is also necessary, but this rotation angle detection The turning power for this is also extremely small. That is, the support shaft 85 is received by the bearing stones 84 having the mortar-shaped recesses 83 at the top and bottom thereof, and the tip of the support shaft 85 is formed to be sharp, and is arranged in the vertical direction. is there.

Therefore, by appropriately setting the position of the weight 77 with respect to the screw shaft 76, the tracing stylus 67 comes into contact with the DUT 5 to rotate the first and second link members 51, 52. The force, that is, the measuring pressure of the probe 67 can be made extremely small.

When the measurement of the predetermined position of the DUT 5 is completed as described above, the probe 67 is raised again and the DUT 5 is replaced, or the same DUT 5 is measured at a different position. The next measurement is performed by arranging it below the child 67, and the measurement is repeated in the same manner. Since the measurement result is displayed on the display device 14, the measurement result is read and recorded, or the output is sent to a printer (not shown) or the like for printing.

According to this embodiment as described above, there are the following effects.

That is, in this embodiment, the spindle 66 to which the tracing stylus 67 is attached is not directly supported by a bearing or the like, but is rotatably supported via the parallel link mechanism 65, and the weight balance of the parallel link mechanism 65 is also supported. Is set by the weight 77, and the rotation of the first and second link members 51, 52 of the parallel link mechanism 65 is detected by the rotation detecting means 92.
The driving force, that is, the urging force associated with the vertical movement of the can be made extremely small, and even if the DUT 5 is easily deformed, for example, even if it is a member such as the outer ring of a ball bearing or a flexible member, it can be accurately measured. be able to. More specifically, the measuring force of the tracing stylus 67 can be set to about 1 gf, and can be set to a value of 1/100 to 1/200 compared with the conventional one. Further, in this measurement, it is possible to perform measurement with high resolution in submicron units without causing deformation such as elastic deformation of Hertz. Further, an angle detection circuit 93 is provided to detect the rotation angles of the first and second link members 51 and 52, and the control circuit 102 is also provided.
Also, since the electric motor 28 is controlled via the drive circuit 103 so that the rotation angle becomes substantially constant, the uneven surface or the like can be continuously measured. Further, since the scale surface 71A of the main scale 71 can be arranged on the extension line of the central axis of the spindle 66 to which the tracing stylus 67 is attached by the action of the notch 55A of the holder 55, the measurement point where the tracing stylus 67 contacts The measurement section and the measurement section are arranged in a straight line, and a measurement system that complies with the so-called Abbe principle can be configured, which also enables highly accurate measurement.

Further, since the slider 27 and the guide member 23 have a rectangular cross section, they do not require a special detent and have a robust structure, so that highly accurate feeding can be performed. Further, in the rotation angle detection means 95 for detecting the rotation of the first and second link members 51, 52 of the parallel link mechanism 65, the photointerrupter 89 requiring electric wiring is provided on the side of the parallel link mechanism 65. Since it is fixedly provided, wiring or the like does not interfere when the slider 27 moves with respect to the guide member 23, and malfunction of the device can be prevented. Further, since the photo interrupter 89 is provided at a fixed position, there is no fear of characteristic changes, and from this point also, highly accurate measurement is possible.

The present invention is not limited to the above embodiment,
Modifications within the scope capable of achieving the object of the present invention are included in the present invention. That is, the dimension measuring apparatus according to the present invention
As shown in FIG. 7, 20 is not necessarily incorporated in the head portion 13 of the measuring machine 10, but only the measuring device 20 is configured as a single item, and the measuring device 20 is attached to a general measuring stand or the like. You may make it measure by measuring. In addition, the first and second link members 51, 5 that form the parallel link mechanism 65.
Each of 2 is formed of a pair of plate members, but each of them may be formed of one plate member. In this case, the bearing structure between the first and second link members 51 and 52 and the slider 27 may be a cantilever structure as in the above-described embodiment, or the slider 27 to the first and second link members may be used. An L-shaped bracket may be provided corresponding to each of 51 and 52, and the pivot shaft may be supported between the bracket and the slider 27 in a both-supported state. Further, the support of the parallel link mechanism 65 is not limited to the one supported by the pivot bearings 45 and 46 as in the above-described embodiment, but may be supported by other general boring. However, the use of the pivot bearings 45 and 46 has the advantages that the parallel link mechanism 65 can be easily and accurately incorporated and the turning torque can be made extremely small. Further, the first and second link members 51, 52 are configured to support the substantially central position thereof by the pivot bearings 45, 46 so that the weight balance can be almost achieved by themselves, but it is not always necessary to do so. Good. However, the above-mentioned embodiment has an advantage that processing and assembling are easy. Further, although the weight 77 is provided on the second link member 52 side, it may be provided on the first link member 51 side, or further on both link members 51, 52. Further, the weight 77 as the biasing means is provided on the screw shaft 76 so as to be adjustable, but it does not necessarily have to be provided so as to be adjustable, and may be provided fixedly. However, if it is provided so as to be adjustable, the biasing force of the tracing stylus 67 can be set extremely precisely, which is advantageous in measurement. Further, the urging means is not limited to the one using only the weight 77 as in the above-described embodiment, but may be a spring, or the weight 77 and the spring may be used together. In addition, the first and second link members 51, 52
Between the other end, that is, between the ends on the side where the weight 77 is provided is connected by a vertically extending link member to form a so-called Roberval mechanism, and the weight balance is achieved by this Roberval mechanism like a so-called balance. It can also be taken. Furthermore, when performing continuous measurement, the movement of the DUT 5 is not limited to the movement of the DUT 5 itself, and
16 may be moved as a so-called XY table together with the table. At this time, the XY table may be driven manually or automatically. Further, the rotation angle detecting means 95 is not limited to the structure of the above-described embodiment, and the photo interrupter 89 is attached to the slider 27 via the bracket, and the first and second link members are provided in the U-shaped groove of the photo interrupter 89. At least one of 51 and 52 may be installed so as to be inserted, and the rotation of the first and second link members 51 and 52 may be directly detected. However, in this way, the slider is moved along the guide member 23.
Since 27 moves, the lead wire from the photo interrupter 89 is moved along with the movement of the slider 27, which is disadvantageous in that it may hinder the movement. Further, the detection means of the rotation angle detection means 95 is not limited to the photo interrupter 89,
Other detection means such as a rotary encoder, a magnetic sensor, or a laser beam may be used. Further, the power transmission means 31 has the same structure as the feed screw shaft as in the above embodiment.
The mechanism is not limited to the one using 34, but may be another mechanism such as a rack and pinion mechanism. Also, the electric motor 28 is a support
It is not limited to the one provided on the side of 21 and may be provided on the side of slider 27. However, the above-described embodiment is more advantageous in terms of reducing the weight of the slider 27 that is the moving member. Further, in continuous measurement, the hold circuit is not used to obtain the maximum value and the minimum value, the movement of the DUT 5 is stopped at the position showing these values while watching the display 14, and the values at this time are set. It may be obtained by reading.

〔The invention's effect〕

According to the present invention as described above, there is an effect that irregularities on the surface of the object to be measured can be measured with high accuracy.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a longitudinal sectional view of this embodiment, FIG. 2 is a front view thereof, FIG. 3 is a side view, and FIG. A plan view, FIG. 5 is an exploded perspective view with a part omitted, FIG. 6 is an enlarged sectional view taken along the line VI-VI of FIG. 1, FIG. 7 is an electric circuit diagram of this embodiment, and FIG. It is a perspective view showing a measuring machine incorporating this example. 5 ... Object to be measured, 20 ... Dimension measuring device, 21 ... Support,
27 …… Slider, 28 …… Motor, 31 …… Power transmission means,
51 …… first link member, 52 …… second link member, 55
…… Holder, 65 …… Parallel link mechanism, 67 …… Stylus, 71
...... Main scale, 73 …… Displacement detector, 74 …… Displacement detection means, 77 …… Weight as biasing means, 93 …… Angle detection circuit, 95 …… Rotation angle detection means, 101 …… Control Means, 102
...... Control circuit, 103 …… Drive circuit.

Claims (1)

[Claims] 1. A support, a slider movably held up and down by the support, an electric motor and a power transmission means for reciprocating the slider along the support, and a predetermined interval in the vertical direction. First and second link members that are arranged and each of which has an intermediate portion rotatably supported by the slider, and one end portions of both the link members are rotatably supported and move in parallel with the slider. Parallel link mechanism configured to include a holder, a probe provided at one end of the holder, and an urging provided so that the holder is urged downward by a predetermined urging force. Means, a rotation angle detecting means for detecting the rotation angles of the first and second link members, a main scale provided on one of the holder and the support, and a displacement detector provided on the other. Including Displacement detection means configured to detect the vertical displacement of the probe, and a control circuit for controlling the drive of the electric motor so that the link member has a predetermined angle based on the output of the rotation angle detection means. A dimension measuring device characterized by being provided.