JP3402990B2 - CMM - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate measuring machine capable of preventing damage to a device due to high-speed collision between a movable element such as a probe and a fixed element.

[0002]

2. Description of the Related Art There are two methods for measuring using a coordinate measuring machine, a method by CNC and a method by manual operation. The CNC method is a method in which a probe is automatically driven by a preset program in response to a command from a host computer. Also,
The manual method includes a method of manually moving the probe using an operation panel to which a joystick or the like is attached in a CNC coordinate measuring machine having a drive mechanism, and a method of directly moving the probe by hand.

[0003]

However, in any of the conventional coordinate measuring machines, in any method, the probe causes a workpiece or other obstacle due to an operation error when the probe is moved or the presence of an unintended obstacle. There was a possibility that the probe or the work would be damaged by colliding with an object at high speed.

The most typical example is an operation error caused by a joystick. That is, in the measurement using a joystick, the joystick lever usually provided on the operation panel called a joystick box is tilted according to the moving direction of the probe, and the drive mechanism is controlled to realize the probe moving speed according to the tilt. To be done.
In the operation with the joystick, since the operation place and the position of the measuring instrument main body are apart from each other, the operator may accidentally collide the probe with the work at high speed unless the operator is sufficiently proficient in the operation. In addition, the operation panel may be removed from the stand and moved to the side of the work for operation, but in this case, the tilt direction of the joystick and the movement direction of the probe may not coincide with each other, which may cause an erroneous operation. Further, even when the work is tilted with respect to the table, the tilt direction of the joystick and the coordinate system of the work do not match each other, so that an erroneous operation is likely to occur.

The cause of the probe moving faster than intended is the existence of a dead zone with respect to the tilt angle of the joystick. That is, in this kind of operation panel, the tilt of the joystick is detected by a potentiometer and a voltage corresponding to the tilt angle is generated, but a slight tilt due to the weight of the joystick, a potentiometer adjustment error, and a temperature drift. A certain range around the neutral position of the joystick is set as a dead zone so that an erroneous movement command is not generated due to the influence of the above. Therefore, unless the operator is skilled in the work, the joystick is tilted more than necessary and the probe moves at an unintended speed.

Further, such a problem can occur sufficiently if the operator is not familiar with the operation because the inertia in each axial direction is large even in the normal manual operation. Furthermore, CNC
It can also occur during automatic feeding by a coordinate measuring machine. In the case of automatic feed, the probe is automatically fed to the work by the part program generated in advance by teaching operation or CAD data, but the machining error of the work, the mounting error, the work and other members placed on the measurement table. In some cases, an unintended obstacle may be present on the probe movement path that should not be present due to the presence or the like. In this case, the probe may collide with the obstacle at a high speed and the member may be damaged.

The present invention has been made in view of the above circumstances, and in a coordinate measuring machine, a collision of a movable member and another member at a high speed is avoided in advance to prevent an accidental damage to the member. An object of the present invention is to provide a three-dimensional measuring machine that can prevent the occurrence of noise.

[0008]

A three-dimensional measuring machine according to the present invention is a three-dimensional measuring machine for measuring an object to be measured by moving a movable element relative to the object to be measured. Restricted area setting means for setting an area around an object existing in the movable range of the movable element as a restricted area, and restricted area information storage means for storing information on the restricted area set by the restricted area setting means. And the current position of the movable element, information on the restricted area stored in the restricted area storage means, the moving direction of the movable element, and the specified speed.
Moving speed limiting means for detecting that the movable element has approached the above-mentioned restricted area at a speed exceeding a predetermined speed based on the degree information, and restricting the moving speed of the movable element above the designated speed. It is characterized by having and. Incidentally, here, the movable element may move itself, or the support base side supporting the object to be measured may move with respect to the movable element.
In this case, the movable element is actually in a fixed state, but since the movable element moves relatively when viewed from the support base, for convenience of description, the movable element is also moved in such a case. Will be expressed.

A more specific aspect of the coordinate measuring machine according to the present invention is a probe which comes into contact with an object to be measured and outputs a contact signal, and a manual operation means for moving the position of the probe. The probe drive means for driving the probe based on operation information of the manual operation means, and the position detection means for detecting the position of the probe driven by the probe drive means, the contact signal output from the probe and the In a coordinate measuring machine for obtaining a measurement result for the object to be measured based on the position of the probe detected by the position detection means, a region around an object existing within the movable range of the probe is set as a restricted region. For setting the restriction area, a restriction area information storage means for storing information on the restriction area set by the restriction area setting means, and the probe Information restriction area stored in the current position and the restricted area storage means, a moving direction及of the probe
And the specified speed information, the probe determines the specified speed.
A moving speed limiting unit that detects that the moving speed of the probe approaches the restricted area at a speed exceeding the moving speed and limits the moving speed of the probe below the specified speed .

The moving speed limiting means, for example, when the probe is approaching the restricted area, the probe decelerates from that position regardless of the moving speed command given by the manual operating means, and the limiting operation is performed. When you reach the area, when you reach the position where you can stop, deceleration starts,
The moving speed of the probe is limited so that the probe is stopped when the probe reaches the limited area.

According to the present invention, the area around the object existing in the movable range of the movable element is set as the restricted area by the restricted area setting means, and the information on the set restricted area is stored in the restricted area information storage means. When the moving element approaches the limiting area, the moving speed limiting means compares the current position of the moving element with the information on the limiting area stored in the limiting area storing means. Since the moving speed is limited, the speed of the movable element is restricted so that it becomes slow in the restricted area even when the moving element approaches the fixed element or another member at high speed due to the speed command, and the moving element moves to another member. It is possible to avoid a collision at high speed.

In particular, when the probe as a movable element is operated by the manual operation means, even if the manual operation means is mistakenly operated, it is detected that the movement speed limiting means has approached the limited area and the moving speed of the probe is detected. Therefore, it is possible to prevent the probe from colliding with a work or the like at high speed.

In this case, the moving speed limiting means decelerates from the probe position when the probe is approaching the restricted region, and when the probe reaches the restricted region, it just starts decelerating when it reaches the position where it can be stopped. By doing so, the probe can be reasonably stopped in the restricted area.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the configuration of a CNC coordinate measuring machine according to an embodiment of the present invention. This coordinate measuring machine is a coordinate measuring machine body 1
A controller 2 for driving and controlling the coordinate measuring machine body 1 and taking in necessary measurement values from the coordinate measuring machine body 1; and a manual operation of the coordinate measuring machine 1 via the controller 2. Operation panel 3 and controller 2
And a host system 4 for processing the measurement values captured via.

The coordinate measuring machine body 1 is constructed as follows. That is, the surface plate 11 is placed on the vibration isolation table 10 so that the upper surface thereof serves as a base surface so as to coincide with the horizontal plane, and the arm supports 12a and 12b which are erected from both side ends of the surface plate 11 are provided. The X-axis guide 13 is supported at the upper end. The lower end of the arm support 12a is the Y-axis drive mechanism 1
4 is driven in the Y-axis direction by the arm support 12b.
Has its lower end supported by an air bearing on the surface plate 11 so as to be movable in the Y-axis direction. X-axis guide 13
Drives the Z-axis guide 15 extending in the vertical direction in the X-axis direction. A Z-axis arm 16 is provided on the Z-axis guide 15 so as to be driven along the Z-axis guide 15, and a contact-type probe 17 is attached to the lower end of the Z-axis arm 16.
When the probe 17 comes into contact with the work 5 placed on the surface plate 11, a touch signal is output from the probe 17 to the controller 2, and the controller 2 takes in the XYZ coordinate values at that time.

FIG. 2 is a block diagram of this coordinate measuring machine. The coordinate measuring machine body 1 is provided with a probe 17 in XYZ.
XYZ axis motor 18 for driving in the axial direction, and XYZ
XY that outputs movement pulse in each axis direction as the axis moves
The Z-axis encoder 19 is built in. On the operation panel 3, a joystick 31 as a manual operation means for driving the probe 17 of the coordinate measuring machine body 1 in the XYZ axis directions by manual operation, and an XYZ coordinate value of the current position of the probe 17 to the controller 2. A coordinate value input switch 32 for inputting is provided.

A CPU 21 is provided in the controller 2, and the CPU 21 controls the drive of the probe 17 and the measurement value fetch control. That is, the XYZ-axis drive control unit 22 drives the XYZ-axis motor 18 of the coordinate measuring machine main body 1 according to a command from the CPU 21, and the XYZ-axis counter 23 counts the pulse signals corresponding to each axis from the XYZ-axis encoder 19. The current position is obtained and fed back to the CPU 21. This current position is sequentially stored in the current position register 24. The CPU 21 controls the drive of the probe 17 based on this feedback information.
Further, the CPU 21 stops the XYZ axis motor 18 in response to a touch signal from the probe 17.

From the operation panel 3, voltage values of potentiometers corresponding to the respective axes depending on the inclination direction and the inclination angle of the joystick 31 are output, and the moving direction / speed of the controller 2 is determined according to the voltage values of the respective axes. The unit 25 determines the moving direction and moving speed of the probe 17. The control area register 26 stores information on a restricted area according to a preset position and size of the work 5. The moving speed control unit 27, based on the current position stored in the current position register 24, the limited area stored in the limited area register 26, and the moving direction and speed information determined by the moving direction / speed determining unit 25, It is determined whether or not the moving speed of the probe 17 is limited to a specified speed, and when it is determined that the moving speed should be limited, the limited speed information is output to the CPU 21.

The host system 4 comprises a host computer 41, a monitor 42, a printer 43, a keyboard 44 and the like.

Next, the operation of the CNC coordinate measuring machine configured as described above will be described. In this coordinate measuring machine, the probe 17 is moved by operating the joystick 31, and the tip sphere of the probe 17 is brought into contact with each part of the work 5 to measure each part of the work 5. In order to avoid collision with a fixed part at high speed, a speed limit area is set in advance. In this example, as the most typical example, the area around the work 5 (work range) is set as the restricted area. FIG. 3 is a flowchart showing the procedure of the setting operation of the restricted area. First,
The probe 17 is moved (S1), the XYZ coordinates of the positions of the respective parts of the work 5 are input to the CPU 21 by operating the coordinate input switch 32 (S2), and the XYZ coordinates are stored until the designated number is input (S3, S3). S4).

In this example, the designated number is the vertical measuring machine, so as shown in FIG.
However, it can be set to an arbitrary number according to work efficiency, recognition accuracy, and the like. Depending on each point, the CPU 21 causes the work 5
The position of is recognized as follows. X-axis-side input Y-axis + side input X-axis + side input Y-axis-side input Z-axis + side input For a vertical measuring machine, Z-axis-side input = 0.

When the input of the designated number is completed, the restricted area (XYZ coordinates) is calculated (S5). The restricted area is, for example, as shown in FIG. 5, an area in which a margin indicated by hatching in the drawing is added to the range indicating the position of the input work 5.

When the probe 17 is moved outside the restricted area after the restricted area is set by the above setting operation, the speed is set by the joystick 31 (for example, the maximum speed is 90 mm / s), and the restricted area is also set. The moving operation of the probe 17 inside is performed at a low speed (for example, 20 mm / s) regardless of the instruction from the joystick 31. When moving from the inside of the restricted area to the outside of the restricted area, it is possible to return to the high speed movement, but in this embodiment, there is a risk that an operator unfamiliar with the operation suddenly changes to the high speed movement during the operation. In order to avoid this, even if the vehicle moves outside the restricted area, it keeps moving at a low speed. Further, as shown in FIG. 5, when the probe 17 is approaching the restriction area at a high speed from point A, the position B at which the probe 17 decelerates from the speed and can be stopped just when the probe reaches the restriction area is the deceleration start position. The deceleration range is from the position B to the position C where the limit area is reached. In this case, the probe 17 is temporarily stopped at the point C where the probe 17 reaches the restricted area,
After that, the probe 17 is prevented from moving unless the joystick 31 is once returned to the neutral position.

FIG. 6 is a flowchart showing a processing procedure of the controller 2 for realizing such movement control. When the joystick 31 is operated, the process of FIG. 6 is activated. First, the moving direction and moving speed are determined by the moving direction / speed determining unit 25 based on the inclination of the lever of the joystick 31 (S11). Moving speed limiting unit 27
Reads the current position of the probe 17 from the current position register 24 (S12), and determines whether or not the probe 17 exists within the restricted area (S13). If it is within the restricted area, a low speed drive instruction is output to the CPU 21 (S1
4) After that, the low speed output is continued until the lever of the joystick 31 returns to the neutral position (S15). When the lever of the joystick 31 returns to the neutral position, probe 1
In order to stop No. 7, stop processing is executed (S16).

On the other hand, when it is determined in step S13 that the probe 17 is outside the restricted area, it is determined whether the probe 17 is moving toward the restricted area (S17). This can be determined by the relationship between the current position stored in the current position register 24 and the moving direction determined by the moving direction / speed determining unit 25. If the probe 17 is not heading in the direction of the restricted area, the speed command instructed by the joystick 31 is output to the CPU 21, and movement control at the instructed speed is performed (S18). In this process, when the lever of the joystick 31 returns to the neutral position (S19), stop processing is executed (S16). Further, when the probe 17 is moving in the direction of the restricted area, the approach processing described later is executed (S20).

FIG. 7 is a flowchart showing details of the approaching process (S20). First, the moving direction / moving speed is determined by the moving direction / speed determining unit 25 from the inclination of the lever of the joystick 31 (S21). The moving speed limiting unit 27 reads the current position of the probe 17 from the current position register 24 (S22). If the instructed moving speed is low (S23), the speed command is not changed and CP is applied.
If the output to U21 (S24) is not low speed,
The deceleration range is calculated (S25). That is, as shown in FIG. 8, when the probe 17 is moving toward the restricted area, if the deceleration curve for stopping before the restricted area C is a curve as shown in the figure, from point A to point B Probe 17 that reached the maximum speed in the process of moving toward the point
Cannot stop at point C in the restricted area unless deceleration starts at point B. Similarly, the probe 17, which has started moving from the point A ′, must start decelerating at the point B ′ corresponding to the intersection of the acceleration curve and the deceleration curve. In this way, the starting points B and B ′ of the deceleration range differ depending on the current position of the probe 17 and its moving speed. Therefore, the moving speed limiting unit 27 calculates the distance required to decelerate from the current speed and stop, and calculates the range expanded from the point C at the beginning of the restricted area by the calculated distance at each sampling. .

If the probe 17 is not within the deceleration range (S26), the speed command as it is is output to the CPU 21 (S24). If the probe 17 is within the deceleration range (S26), it is determined whether or not it is within the restricted area (S26).
27) If the limit area is not reached, deceleration processing is executed (S28), and the decelerated speed command is output to the CPU 21 (S24). In the deceleration process, the speed command value may be reduced by a constant speed at constant time intervals so that the speed becomes 0 when the vehicle enters the restricted area. In this process, if the lever of the joystick 31 is returned to the neutral position (SS29), stop processing is executed (S3).
0). If the probe 17 reaches the restricted area during the deceleration process (S27), the stop process is executed (S3).
1) After that, unless the lever of the joystick 31 is returned to the neutral position, the probe 17 cannot be moved (S32).

By the above processing, it is possible to prevent the probe 17 and the work 5 from colliding at high speed even if the operation panel 3 is operated by mistake. In the above embodiment, the remote control joystick 31 provided on the operation panel 3 is used as the manual operation means. However, as shown in FIG. 9, the joystick 31 is directly attached to the Z-axis arm 16. The small joystick 33 is operated to operate the probe 17
The present invention can also be applied to the case of moving and operating. At least two two-dimensional force sensors, not shown, are provided inside the operation box 34, and the two-dimensional force sensor detects the magnitude and direction of the force applied to the joystick 33 by the operator. The probe 17 is driven and controlled at a speed corresponding to the detected force in the detected direction. At that time, as described above, regardless of the force applied to the joystick 33, when the vehicle approaches the limited area, the deceleration control → stop processing is executed so that the movement within the limited area is performed at low speed. It should be controlled to.

Further, in the above embodiment, the limiting area around the work 5 is set in advance by the teaching operation, but the limiting area may be set based on the CAD information as the work design information. Further, a method of setting the restricted area by image recognition can be considered. Figure 10
FIG. 3 is a perspective view of a CNC coordinate measuring machine main body showing this example. Note that, in FIG. 10, parts corresponding to those in FIG. 1 are denoted by the same reference numerals and detailed description thereof will be omitted.

In the coordinate measuring machine main body 1, a vibration isolation table 10 extends forward of the surface plate 11 in the Y-axis direction, and the first illumination device 51 is installed on the extended vibration isolation table 10. Has been done. A measurement area is formed above the surface plate 11, and an imaging area is formed above the first illumination device 51. A stage drive mechanism 52 is installed so as to connect these two regions. The stage drive mechanism 52 includes two parallel rails 61 that connect the surface plate 11 of the coordinate measuring machine body 1 and the first lighting device 51, and a U-shaped slide that is guided and moved by the parallel rails 61. It is composed of a table 62, a motor 63 that drives the slide table 62, and a screw-shaped drive shaft 64. The pallet 53 is mounted on the slide table 62. This pallet 53
Is a stage on which the work 5 is placed, and is composed of a transparent glass plate 71 and a frame body 72 mounted on the peripheral edge of the glass plate 71. Positioning holes 73 are formed in the frame 72, and the holes 73 and the positioning bosses 74 provided on the slide table 62 are fitted to position the pallet 53 on the slide table 62.

A CCD camera 5 for picking up an image of the work 5 is provided above and sideways of the work 5 arranged on the pallet 53.
4, 55 are arranged respectively. A second illumination device 56 is arranged on the side of the work 5 opposite to the CCD camera 55. The lighting devices 51 and 56 each include a case 75 in which a light source (not shown) is housed, and a semitransparent plate 76 that seals the case 75 and uniformizes the light from the light source. Reference numeral 20 in the figure denotes an automatic probe exchange device provided in the measurement area.

FIG. 11 is a block diagram showing a signal / information processing system of this system. CCD cameras 54, 55
The image information imaged in (1) is supplied to the image processing device 81, where the position of the work and the size of the work are obtained by the image recognition processing. CMM data processor 8
2 calculates a restricted area from the calculated work position and work size, and supplies it to the controller 2. The controller 2 drives the stage drive mechanism 52 and the coordinate measuring machine body 1.

According to the three-dimensional measuring machine configured as described above, the pallet 53 is moved to the CCD 5 in the measurement start state.
5, 56 are arranged in an imaging area where imaging can be performed. In this state, when the work 5 is carried onto the pallet 53 by a conveyance means such as a human or a robot, the CCD camera 5
The work 5 is imaged by 5, 56. At this time, the illumination light from the first illumination device 51 passes through the parallel rails 61, the hollowed-out portion of the slide table 62 and the glass plate 71 of the pallet 53 to illuminate the work 5 from below. Since the CCD camera 54 images the work 5 from above on the side opposite to the illumination device 51, the work 5 becomes backlit and the contrast between the work 5 and the background is increased as shown in FIG. 12A. It is possible to obtain clear image information with emphasis. Similarly, the image information of the side surface of the work 5 obtained by the CCD camera 55 that receives the illumination light from the second illuminating device 56 shows that the contrast between the work portion and the background is as shown in FIG. The image information is emphasized and clear. This image may be binarized by the image processing device 81, and the position and size of the work may be obtained from the XYZ coordinates of the edge.

According to this embodiment, even if there is an unintended obstacle due to a machining error of the work 5 or another member erroneously placed around it during automatic measurement, these and the probe 17 are There is an advantage that the collision at high speed can be avoided in advance.

Although the restricted area is provided around the work 5 in the above embodiments, the jig supporting the work 5 and a part of the coordinate measuring machine body 1 itself may not interfere with the probe movement path. If there is a possibility, a restricted area may be set in that part. Further, it is conceivable to set the restricted area not only on the fixed side interference point but also on the movable side, for example, the probe, the Z-axis arm of the measuring machine body, and the like. For example, as shown in FIG. 13, probes 17 and 17 ′ having different sizes are considered to have different interference ranges. Therefore, depending on the probe to be used, a movable region is also set with a restricted region as shown by the diagonal lines in the drawing, and the work is The movable-side restriction area is added to the 5-side restriction area. Specifically, in the case of measuring the outer shape area of the work 5, the movable side restriction area is offset outward from the fixed side restriction area, and in the case of the inner shape area of the work 5, the fixed side restriction area is measured. The actual restriction area is determined by offsetting the restriction area on the movable side inward in the restriction area.

The restricted area is XYZ as described above.
Depending on the shape of the work 5, as shown in FIG. 14, in addition to the coordinate system, it may be held by function display such as center coordinates and radius r. Furthermore, FIG.
As shown in FIG. 5 (a), the workpiece 5 is the measuring machine coordinate system X, Y.
If the work 5 itself is deformed with respect to the measurement coordinate systems X and Y as shown in FIG. 7B, the drive axis of the joystick 31 is moved. Work coordinate system WX, WY in the direction / speed determination unit 25
The measurement work may be performed by converting to. In such a case, it is preferable to set the restricted area in the work coordinate systems WX and WY. When repeatedly measuring the same type of work, once the limited area that has been set is saved as a limited area library, the subsequent work becomes easier.

[0037]

As described above, according to the present invention, the area around the object existing within the movable range of the movable element is set as the restricted area by the restricted area setting means, and the set restricted area is set. If the information is stored in the restricted area information storage means, the moving speed restriction means compares the current position of the movable element with the information on the restricted area stored in the restricted area storage means, and the movable element becomes the restricted area. Since the moving speed of the movable element is limited when approaching, even if the moving element approaches the fixed element at high speed by the speed command, the speed of the moving element is limited to be low in the limited area, It is possible to avoid the collision with the fixed element at high speed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of a CNC coordinate measuring machine according to an embodiment of the present invention.

FIG. 2 is a functional block diagram of the measuring machine.

FIG. 3 is a flowchart showing a restricted area setting process in the measuring machine.

FIG. 4 is a diagram for explaining a data input operation in the same restricted area setting process.

FIG. 5 is a diagram for explaining an outline of speed limiting processing in the measuring machine.

FIG. 6 is a flowchart showing a joystick drive process in the measuring machine.

FIG. 7 is a flowchart of a probe approaching process in the driving process.

FIG. 8 is a diagram for explaining a method of determining a deceleration range in the drive process.

FIG. 9 is a perspective view showing a manual operation means according to another embodiment of the present invention.

FIG. 10 is a perspective view showing a coordinate measuring machine according to still another embodiment of the present invention.

FIG. 11 is a functional block diagram of the measuring machine of the embodiment.

FIG. 12 is a diagram showing a work image to be processed in the embodiment.

FIG. 13 is a diagram for explaining still another embodiment of the present invention.

FIG. 14 is a diagram for explaining still another embodiment of the present invention.

FIG. 15 is a diagram for explaining still another embodiment of the present invention.

[Explanation of symbols]

1 ... Coordinate measuring machine main body, 2 ... Controller, 3 ... Operation panel, 4 ... Host system, 5 ... Work.

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Claims (3)

(57) [Claims] 1. A coordinate measuring machine for measuring an object to be measured by moving a movable element relative to the object to be measured, comprising: Restricted area setting means for setting an area as a restricted area, restricted area information storage means for storing information on the restricted area set by the restricted area setting means, current position of the movable element , the restricted area storage means Information of the restricted area stored in the moving direction of the movable element and the finger.
Based on the information on the fixed speed, the movable element exceeds the predetermined speed
And a moving speed limiting means for detecting that the moving speed of the movable element approaches the limited area at a certain speed, and limiting the moving speed of the movable element below the designated speed . 2. A probe for contacting an object to be measured and outputting a contact signal, a manual operation means for moving the position of the probe, and driving the probe based on operation information of the manual operation means. A probe driving unit and a position detecting unit for detecting the position of the probe driven by the probe driving unit are provided, and based on the contact signal output from the probe and the position of the probe detected by the position detecting unit. In a coordinate measuring machine for obtaining a measurement result for the object to be measured, a restricted area setting means for setting an area around an object existing in the movable range of the probe as a restricted area, and the restricted area setting means Restricted area information storage means for storing information on the set restricted area; and a current position of the probe and stored in the restricted area storage means. Information restricted area, the moving direction and the finger of the probe
If the probe exceeds the specified speed from the information of the specified speed
And a moving speed limiting unit that detects that the moving speed of the probe is closer than the specified speed, and that the moving speed of the probe is limited to a specified speed . 3. The moving speed limiting means, when the probe is approaching the limiting area, regardless of a moving speed command given by the manual operating means, the probe decelerates from the position and the limiting area. 3. The moving speed of the probe is limited so that the deceleration is started when the stop position is reached and the probe is stopped when the limit area is reached. Coordinate measuring machine described.