JPH0815704B2 - Machine motion accuracy measuring device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relative two-axis movement between a spindle of a machine used in a machining site such as a machine tool or a coordinate measuring machine or a measuring site and a table on which a work is installed. The present invention relates to a machine motion accuracy measuring device for measuring the accuracy of circular motion by means of, in particular, it is possible to measure the motion accuracy of circular motions of various set radii R from a small radius of a machine to a relatively large radius, and the measuring device itself The present invention relates to a motion accuracy measuring device that extracts an intrinsic measurement error factor in advance as a correction value and corrects the measurement of motion accuracy so that the motion accuracy of a machine can be measured with high accuracy.

[0002]

2. Description of the Related Art In a machine tool, a coordinate measuring machine, or the like, a circular movement is carried out by relative biaxial movement between a main shaft and a table facing the main shaft, so that a cylindrical hole is machined in a workpiece or a true workpiece is machined. Circularity and cylindricity are measured. Therefore, the circular motion accuracy of the machine directly affects the processing accuracy and measurement accuracy of the processed product. Therefore, conventionally, various measuring devices have been provided which measure highly accurately the circular motion accuracy due to the relative biaxial movement between the main shaft of the machine and the table.

For example, in a known method as a disk method, a ring-shaped master circle is mounted on a table of a machine, which is the object to be measured, and a circular movement is imparted to the master circle by two-dimensional synthetic movement of the table. Then, at this time, the probe of the two-dimensional displacement sensor is brought into contact with the same master circle under a constant pressure so that the probe also performs two-dimensional circular motion, and the error of the circular motion of the probe with respect to the true circle is measured and detected. Due to
There is a method of detecting the circular motion accuracy of the machine.

Further, a so-called double ball bar in which two high-precision balls are held at both ends of one bar is received by a spherical seat provided on the main shaft of the machine and the table. When a relative circular motion is performed in a two-dimensional plane, the radial displacement of the circular motion is detected by a one-dimensional displacement sensor such as a strain gauge incorporated in the bar of the double ball bar to detect the fluctuation of the radius of the circular motion. DB that measures the accuracy of the relative circular motion between the machine spindle and the table by measuring
There is a well-known method as the B (Double Ball Bar) method.

However, the above-mentioned disc method is troublesome and expensive because it is necessary to prepare the required number of master circles according to the size of the diameter of the circular movement to be measured when measuring the precision of the circular movement of the machine. There is a problem that becomes. Further, since the master circle and the probe of the two-dimensional displacement sensor are in contact with each other under a constant contact pressure, the measurement accuracy is slightly deteriorated due to the influence of friction at the contact portion, and the friction force is affected by the influence of the measurement environment. There is a problem in that the influence on the measurement accuracy becomes even greater due to the fluctuation. For example, there is a drawback that floating dust in the air enters between the master circle and the probe to cause a measurement error, and there is room for improvement in highly accurate measurement of circular motion.

Further, in the latter method using a double ball bar, the double ball bar itself is manufactured by 2 steps.
Connect the center of two high precision spheres with one bar, and
Manufacturing work that incorporates displacement measuring means into the bar is difficult,
In terms of function, there is a drawback that the displacement sensor incorporated in the double ball bar cannot sufficiently detect the movement in the area where the diameter of the circular movement is small, because the movement displacement itself is small. There is also a problem that an arbitrary radius cannot be measured.

In order to solve the problems of the above-mentioned two known methods for measuring the accuracy of circular motion, the motion of a machine already proposed as Japanese Patent Application No. 1-255281 as one of the results of the earnest research by the present applicant. There is a measuring device. That is, when the motion measuring device is outlined, in measuring the motion accuracy of circular motion due to relative biaxial movement between the main shaft and the table, a rotary shaft provided on the main shaft and a table substantially parallel to the rotary shaft are provided. One rotation shaft is fixed to one rotation shaft so that the same point always faces the other rotation shaft with respect to the rotation shaft provided on the side so as to make a relative circular motion, and the other rotation shaft is An attitude control shaft engaged so as to be movable only in the radial direction is provided, and displacement measuring means or a reference block is provided on the attitude control shaft or the rotary shaft on the side to which the attitude control shaft is fixed, and the other rotary shaft. The side is equipped with a master gauge that cooperates with the former displacement measuring means, or is provided with displacement measuring means for detecting the latter reference block, or conversely, the attitude control axis or the attitude control axis. Can be moved in the radial direction Displacement detecting means is provided on the rotating shaft on the engaged side, and at that time, a master gauge that cooperates with the displacement detecting means is provided on the rotating shaft on the side on which the other attitude control shaft is fixed, or the attitude controlling shaft is fixed. The reference block is provided on the rotating shaft on the driven side or the attitude control shaft itself, and the accuracy of the motion is determined by the displacement detecting means during the circular motion by the relative biaxial movement of the main shaft and the table. It is taken out as a displacement output to the outside through the analysis processing.

[0008]

However, even in the above-mentioned motion accuracy detecting device for a machine already proposed,
There are problems to be solved. That is, when a relative circular movement is performed between the main spindle of the machine and the table by movement in two axial directions, the circular movement error due to the accuracy of the control operation in the feed control system of the machine causes the diameter of the circular movement to change. It occurs remarkably when set to a small value, but when trying to set the diameter of the circular motion to a small value in order to measure the error caused by such a control system, the same attitude control axis is used on the machine spindle side and table side. Since they are engaged with both, the radial distance between the axis of the rotary shaft provided on the main shaft side and the axis of the rotary shaft provided on the table side is gradually reduced to reduce the diameter of the circular motion. When they are made to rotate, interference between the rotating shafts eventually occurs, and there arises a problem that it becomes impossible to measure the accuracy of circular motion having a diameter of a certain value or less, that is, the region of minute circular motion.

Moreover, if the diameter of the above-mentioned minute circular motion can be further reduced to set the diameter to a zero value, the measurement accuracy of the motion accuracy measuring device itself can be detected. Therefore, if the detected value is used as a correction value, Knowing that the measurement accuracy of the motion accuracy of the machine will become higher and higher, we have worked on the development of the machine motion accuracy measuring device that can make the diameter of the circular motion as close to zero value as possible.

That is, the object of the present invention is to measure the motion accuracy when performing a circular motion by relative biaxial movement between the main shaft of the machine and the table, and from the circular motion of small diameter to the circle of relatively large diameter. A machine that can measure the accuracy of circular motion in a wide diameter range up to the motion, and separate and measure the motion error caused by the machine control system and the motion error caused by mechanical factors such as the feed mechanism. It is intended to provide a motion accuracy measuring device.

Another object of the present invention is to detect and measure a roundness error caused by the measuring device itself to correct the motion accuracy of the machine, and to correct the motion accuracy of the machine. It is intended to provide a motion accuracy measuring device.

[0012]

In order to solve the above-mentioned object of the invention, the present invention is directed to a posture control interposed between a rotary shaft mounted on a main shaft of a machine and a rotary shaft mounted on a table of the machine. Without using a single shaft as a jig,
Adjusting the radius of movement by forming two rods, one with a radius adjustment rod attached to one of the rotating shafts and the other with a slide rod that is slidable only in the radial direction on the other rotating shaft, into a jig with a stepped shape The axes of the two rotary shafts are brought close to each other by a rod so that the circular motion diameter between the main shaft and the table can be appropriately set from a small diameter value including a zero value to a relatively large diameter, and at the same time, always relatively circular motion in a state in which the same point facing one of the rotary shaft only in the slidable displacement in the radial direction of the circular motion relative to the rotational axis line de rod in a circular motion process around the other axis of rotation It is configured to measure the motion accuracy of the circular motion by the cooperation of the displacement measuring means and the stylus during the operation. We have realized a motion accuracy measuring device that does not cause . Therefore, it is possible to separate the control error of the control system that controls the movable elements such as the main shaft of the machine and the table via the servo system from the mechanical error of the feed mechanism of the machine to measure the motion accuracy of the machine, and to measure the motion accuracy of the measuring device itself. Thus, a motion accuracy measuring device capable of performing high-precision motion accuracy measurement by detecting an error and correcting the motion accuracy measurement data of the machine was obtained.

According to one aspect of the present invention, there is provided a first rotary shaft mountable on a main shaft of a machine and a second rotary shaft mountable on a table of the machine, wherein the main shaft and the table are connected to each other. A motion accuracy measuring device for measuring motion accuracy of circular motion due to relative biaxial movement between the main shaft and the table when the axial center distance between them is set to a predetermined distance value R. And a moving radius adjusting rod having a length in the radial direction of the circular movement, which is attached to any one of the two rotating shafts, and is integrally formed with the moving radius adjusting rod in a stepped shape,
The other rotation shaft has a slide rod that is movably engaged in the radial direction of the circular motion so that the distance value R can be set to any value including zero, and the first and second rotation shafts An attitude control jig for performing relative circular movement with the distance value R as a radius in a posture in which one rotation axis always faces the same point around the other rotation axis, and one rotation axis The probe held at one end of the slide rod of the mounted attitude control jig and the other rotating shaft with which the slide rod of the attitude control jig is movably engaged are fixed, and cooperate with the probe. Then, there is provided a motion accuracy measuring device for a machine, which comprises a displacement measuring means for generating a measurement output according to the radial displacement of the circular motion. According to another aspect of the present invention, there is provided a first rotary shaft mountable on a main shaft of a machine and a second rotary shaft mountable on a table of the machine, and an axial center between the main shaft and the table. A motion accuracy measuring device for measuring motion accuracy of circular motion by relative biaxial movement between the main shaft and a table when the distance is set to a predetermined distance value R, wherein the first and second rotary shafts are provided. Which is attached to one of the rotating shafts, and which is formed integrally with the movement radius adjusting rod having a length in the radial direction of the circular movement and the movement radius adjusting rod, and in a stepped shape,
The other rotation shaft has a slide rod that is movably engaged in the radial direction of the circular motion so that the distance value R can be set to any value including zero, and the first and second rotation shafts A posture control jig for performing a relative circular movement with the distance value R as a radius in a posture in which one rotation axis always faces the same point around the other rotation axis. A probe fixed to the other rotating shaft with which the slide rod is movably engaged, and one end of the slide rod of the attitude control jig mounted on the one rotating shaft, and held together with the probe. Then, there is provided a motion accuracy measuring device for a machine, which comprises a displacement measuring means for generating a measurement output according to the radial displacement of the circular motion. Hereinafter, the present invention will be described in more detail with reference to the embodiments shown in the accompanying drawings.

[0014]

1 is a longitudinal sectional view of a machine motion accuracy measuring apparatus according to the present invention, and FIGS. 2 and 3 show a machine motion accuracy measuring apparatus according to the present invention comprising an attitude control jig and a probe. 4 is a front view showing an embodiment and a side view seen from the line 3-3,
FIG. 5 is a side view taken along the line 4-4 of FIG. 1, and FIG. 5 is a first rotation diagram in which the motion accuracy measuring device including the attitude control jig and the stylus shown in FIGS. The circularity error of the measuring device itself is measured by inserting the radius between the spindle and the table to a zero value by inserting it between the shaft and the second rotary shaft mounted on the machine table. FIG. 6 is a front view showing a setting state in which the measurement accuracy can be measured, and FIG. 6 shows the measurement of the motion accuracy using the motion accuracy measuring device according to the present invention by applying the correction due to the circularity error of the measuring device itself. FIG. 7 is a flow chart showing the measurement and analysis process in this case, and FIG. 7 is a front view showing another embodiment in which the machine motion accuracy measuring apparatus according to the present invention is constituted by a posture control jig and displacement measuring means.

Referring to FIGS. 2 and 3, an attitude control jig and a probe are shown as essential components in the first embodiment of the machine motion accuracy measuring apparatus according to the present invention. The attitude control jig 10 is formed as a measuring jig including a radius-of-movement adjusting rod 12, a spacer member 14, and a slide rod 16, and is a first jig mounted on a main shaft of a machine as described later. The rotary shaft is inserted between the rotary shaft and a second rotary shaft mounted on the table of the machine. Here, the movement radius adjusting rod 12, the spacer member 14, and the slide rod 16 are tightening bolts 18 (only one tightening bolt 18 is shown in FIG. 2; Three tightening bolts 18 are used.) Through the holes formed in the movement radius adjusting rod 12 through the spacer member 14 to engage with the screw holes formed in the slide rod 16 and tighten and fix, the three members are integrated. And the movement radius adjusting rod 12 and the slide rod 16 are formed into a spacer member 14
Are formed into two shaft bodies that are arranged in a staggered manner with their axes substantially parallel to each other. In this example,
As is apparent from FIG. 2, the radius-of-movement adjusting rod 12 and the slide rod 16 each have a cylindrical shaft shape, and a spacer member 14
In order to staggered arrangement having a predetermined distance between the Ryo桿12, 16 has a square bar shape having a predetermined Thickness. Further, the radius-of-movement adjusting rod 12 has a flat surface 12a having a sufficient length in the axial direction on the side surface thereof, and a surface to which a fixing screw on the rotating shaft is locked when it is mounted and fixed to the rotating shaft. Is done.

Further, the slide rod 16 of the attitude control jig 10
A bracket member 20, which is formed as a plate-shaped member, is fixed to the rear end side of the bracket member with a set screw 22.
At 0, a probe 24 is held, which makes it possible to perform a motion accuracy measuring action in cooperation with a displacement measuring means described later. The tracing stylus 24 has a screw shaft 26, and has a front end surface 26a of a screw shaft portion projecting forward from the bracket member 20 as a measured surface that cooperates with the displacement measuring means, and the adjusting ring 2 is provided on the rear end side.
It has 6b and is screw-engaged with the bracket member 20. Further, the tracing stylus 24 has a rotating ring 28a screwed from the side surface of the bracket member 20 toward the side surface of the screw shaft 26.
It is provided so as to be immovably fixed to the bracket member 20 by an attached set screw 28.

Next, by using the motion accuracy measuring device including the attitude control jig 10 and the tracing stylus 24 described above,
A measuring method for measuring the motion accuracy of the relative circular motion between the main shaft of the machine and the table will be described with reference to FIGS. 1 and 4. Now, referring to FIG. 1, a main spindle 30 and a table 32 of a machine are shown, and a first rotary shaft 40 is detachably attached to the former main spindle 30 via a rotary shaft holder 34, and the latter. The table 32 has a second rotary shaft 6
0 is also detachably attached via an appropriate clamp member (not shown). The above-mentioned first and second rotating shafts 4
The structure of Nos. 0 and 60 has the same structure as the rotating shaft provided as an essential element in the machine motion accuracy measuring device proposed by the present applicant (Japanese Patent Application No. 1-255281). The former first rotary shaft 40 has two
It has a rotary shaft main body 46 rotatably supported around a central axis through two rotary bearings 44, 44, and a two-forked structure portion forming a horizontal jig holding hole 46a at the lower end of the rotary shaft main body 46. Clamp screw 4 is provided as shown in FIG.
8 is formed so as to clamp and hold the held body inserted in the jig holding hole 46a.

On the other hand, the second rotary shaft 60 is connected to the table 32.
A rotary shaft main body 68 rotatably supported via two rotary bearings 66, 66 is provided in a housing 64 having a pedestal 62 fixed at its lower end, and a horizontal circular hole is provided at the upper end of the rotary shaft main body 68. Shaped sliding grooves 68a are formed. The detection end 70a of the displacement gauge 70 extending in the center hole of the rotary shaft main body 68 faces outward from the side surface of the rotary shaft main body 68, and the other end is provided at the lower end of the rotary shaft main body 68. It is formed so that it can be connected to the connector 72 and the measurement output can be sent to the outside. The displacement meter 70 is formed of, for example, a well-known eddy current sensor or electrostatic capacitance sensor, and cooperates with a tracing stylus 24 (see FIG. 2) of a motion accuracy measuring device as will be described later, to make a circle. It is provided to measure the motion accuracy of the motion. In addition, this second rotating shaft 6
Further, a phase detection proximity switch 74 is provided in the housing 64 of 0, and detects four detection holes 76a formed at equal intervals in a phase detection plate 76 fixed to the lower end of the rotary shaft body 68. The rotational position of the quadrant switching of the circular motion on the two-axis (X, Y) plane of the main shaft 30 can be detected.

When measuring the accuracy of the relative circular motion of the main shaft 30 and the table 32, the motion according to the present invention shown in FIGS. 2 and 3 between the two rotary shafts 40 and 60 described above. The accuracy measurement device is inserted and set, and the measurement is performed. That is, as shown in FIG. 1, for example, the first rotating shaft 40
In the jig holding hole 46a at the lower end of the rotary shaft main body 46, the movement radius adjusting rod 12 of the attitude control jig 10 is horizontally inserted and fixed by the clamp screw 48, and slides provided in different steps via the spacer member 14. Insert the rod 16 into the horizontal sliding groove 68a of the rotary shaft body 68 of the second rotary shaft 60.
Engage and insert. At this time, the movement radius adjusting rod 12 is set so that the distance between the center axes of the first and second rotating shafts 40 and 60 matches the desired radius value R of the circular movement. That is, the spindle 3
When the radius of the circular movement due to the biaxial movement between 0 and the table 32 is set to the desired value R and measured, a distance equal to the desired value R is set when the movement radius adjusting rod 12 is inserted. The same setting is performed along the movement radius adjusting rod 12 so that the distance between the center of the spindle-side rotating shaft body 46 and the center of the opposing table-side rotating shaft body 68 becomes equal to the desired setting value R. When the set distance R is obtained by adjusting and moving the rotating shaft 40 side of No. 1, the clamp screw 48 may be locked by being fixed to the flat surface 12a of the side surface of the movement radius adjusting rod 12.

It should be noted that, in the attitude control jig 10 according to the present invention, the main shaft 30 in which the movement radius adjusting rod 12 and the slide rod 16 face each other with the spacer member 14 interposed therebetween.
Side lower end of the first rotating shaft 40 and the second rotating shaft 6 on the table side
Since a predetermined space is maintained between the center axis of the first rotary shaft 40 and the center axis of the second rotary shaft 40, it is possible to bring the center axis of the first rotary shaft 40 closer to the center axis of the second rotary shaft 60. It is possible to realize a state in which the diameter of is reduced to perform a circular motion of a small diameter. Furthermore, it is possible to realize a state in which the radius R of the circular motion is substantially zero. The movement radius adjustment rod 12 and the slide rod 16 of the posture control jig 10 described above.
When the settings of and are completed, the tip surface 26a formed at the tip of the screw shaft 26 of the tracing stylus 24 is moved to the detection end 7 of the displacement gauge 70.
It is set so as to face 0a with a minute gap. The setting of the tracing stylus 24 is set by advancing and retracting the screw shaft 26 with respect to the detection end 70a of the displacement meter 70, and is clamped to the bracket 20 with the set screw 28 when a predetermined gap value is established. To be done.

When the setting of the attitude control jig 10 and the tracing stylus 24 is completed, the preparation for measuring the motion accuracy of the circular motion between the spindle 30 and the table 32 is completed. Next, for example, when the table 32 is subjected to a circular motion by an interpolation method in a plane of two axes (X axis, Y axis) orthogonal to each other, the second rotation axis 6
The center line of the first rotation shaft 40 performs a circular motion with a radius R around the center axis of 0. At this time, since the attitude control jig 10 is interposed between the rotary shafts 40 and 60, the first rotary shaft 4
When 0 is maintained around the second rotation axis 60, the same point always faces each other, that is, the tip surface 26a of the probe 24 and the detection end 70a of the displacement gauge 70 face each other, while the relative circular motion is maintained. It is done. Therefore, at this time, if the motion accuracy of the same circular movement fluctuates, the slide rod 16 of the attitude control jig 10 slides and displaces in the slide groove 68a of the second rotary shaft 60, and the displacement amount is measured. Is detected by the cooperative measurement action of the displacement gauge 70 and the displacement gauge 70, and is output from the displacement gauge 70 as measurement data. Therefore, it is possible to measure the motion accuracy of the circular motion by analyzing the measurement data. The measurement data is detected as roundness measurement data in the same manner as the measurement data disclosed in Japanese Patent Application No. 1-255281 described above by the present applicant. In addition, regarding the method of analyzing the roundness measurement data, for example, refer to the literature (“Precision Measurement (2), Chapter 5, (1)” issued by Corona Publishing Co., Ltd.).
Since the difference between the maximum value and the minimum value of the radial displacement with respect to the center of the circle may be calculated as described in "Measurement of Roundness"), it will not be described in detail here.

Now, according to the present invention, as can be understood from the above, by the movement radius adjusting rod 12 of the attitude control jig 10, the relative circular movement due to the biaxial movement between the main spindle of the machine and the table. It is also possible to set the radius R to a minute value close to a substantially zero value. This means that by measuring the accuracy of minute circular motions, which reduces the effect of mechanical errors caused by the machine's feed mechanism, it is possible to use a feed servo system such as a machining center or a computer-controlled CMM. It is possible to detect and measure the error of the biaxial movement that occurs due to the control system of the automatic machinery, and thus it is possible to separate and measure the mechanical error and the error due to the control system. By analyzing the error caused by the system, it can be used for improving the machine feed control system.

According to the invention, it is also possible, as shown in FIG. 5, to set the radius R of the relative circular movement between the machine spindle 30 and the table 32 to substantially zero. . In this way, the radius R is set to zero, that is,
If the center of the first rotating shaft 40 on the side of the main shaft 30 of the machine and the center of the second rotating shaft 60 on the side of the table 32 are made to coincide with each other, both the main shaft 30 and the table 32 perform a circular motion with a radius of zero. It means that both of them are actually in a stationary state. As a result, external means, for example, the rotary motor 80 shown in FIG. 5, a belt / pulley mechanism 88 having a small diameter pulley 82, a large diameter pulley 84, and a belt 86, and a drive arm 90 suspended from the large diameter pulley 84. Attitude control jig 1 via
0 is given a rotational driving force, and the first and second rotary shafts 40, 6
If the displacement measurement is performed between the tracing stylus 24 and the displacement gauge 70 by causing the rotation shaft main bodies 46 and 68 of 0 to rotate at a constant speed, the true motion of the motion accuracy measuring device according to the present invention during rotation can be obtained. Roundness error can be measured.

As described above, if it is possible to detect and measure the roundness error of the measuring device itself, the accuracy of the circular motion between the main shaft 30 of the machine and the table 32 at various radii R can be measured. In the process, the roundness error of the measuring device itself can be detected and measured in advance, and the data of the measurement result can be used to correct the measuring device error when measuring and analyzing the motion accuracy of the machine. FIG. 6 shows the former measurement data and the latter measurement data when measuring the circularity error of the motion accuracy measuring device itself and then causing the machine to execute a circular motion of radius R to measure the motion accuracy. It is a flow chart which shows a processing flow in the case of amending and performing true motion accuracy measurement. In FIG. 6, the measurement process on the left side shows a roundness error measurement flow of the motion accuracy measuring device according to the present invention. The roundness error data obtained by this measurement process is temporarily stored in a data memory of a computer, and then, Execute the flow shown in the right side of the figure to measure the motion accuracy in the actual circular motion of the machine, and use the measurement data of the roundness error of the device that stores the obtained measurement data in the data memory first. The measurement error correction process for correction is performed to obtain the measurement data of the true motion accuracy in the circular motion of the machine. In the flowchart of FIG. 6, the misalignment calculation and misalignment correction steps in the accuracy measurement steps of the left-side measuring device and the right-side machine are performed in the above-described known roundness measurement data analysis process. This is a known process performed according to a well-known arithmetic expression for correcting eccentricity in the roundness measuring stage.

FIG. 7 is a front view showing another embodiment of the machine motion accuracy measuring apparatus according to the present invention. The difference between the embodiment and the embodiment shown in FIGS. 2 and 3 is the attitude control. Jig 1
The probe 24 held by the slide rod 16 of 0 through the bracket 20 is replaced with the displacement measuring device 100, and instead of the second
1 in place of the displacement meter 70 provided on the rotary shaft 60 of
No. 02 or a master ring is attached, and displacement measurement data is obtained from the displacement meter 100. The displacement measuring instrument 100 of this embodiment is a wireless micrometer that wirelessly transmits a measurement output from an attached antenna and receives the measurement output by the measuring device main body 104.

In the two embodiments of the machine motion accuracy measuring apparatus according to the present invention described above, the attitude control jig 1 is used.
The movement radius adjusting rod 12 of 0 is fixed to the first rotary shaft 40 on the main shaft side of the machine, and the slide rod 16 is attached to the second rotary shaft 60 on the table side in the radial direction of the circular motion, that is, in the (radial direction). Although it has been described that the measurement of the motion accuracy is performed with the configuration that is slidably mounted, conversely, the motion radius adjusting rod 12 is fixed to the second rotating shaft 60 on the table side, and the slide rod 16 is attached to the main shaft side. It is also possible to implement by a configuration in which the first rotary shaft 40 is slidably mounted in the radial direction. In that case,
It is necessary to correspondingly change the arrangement and configuration of the displacement gauge and the stylus. Further, in the attitude control jig 10 of the embodiment, the movement radius adjusting rod 12 and the slide rod 16 are constituted by the cylindrical shaft body, but it is not always necessary to form the cylindrical shaft body, and those skilled in the art will know that It is also possible to form the movement radius adjusting rod and the slide rod with the shaft. In addition, it is a fact that processing can be facilitated if it is formed into a cylindrical shaft.

[0027]

As is apparent from the above description, according to the present invention, when measuring the motion accuracy of the machine motion, particularly the circular motion set to the radius R, the radius R is changed from a zero value to a minute radius value. It is possible to measure the motion accuracy of the circular motion of a wide range of machines, which reaches a large radius value through, and especially by measuring the motion of minute circular motion, the motion accuracy error and the machine feed control caused by the mechanical factors of the machine. Since the motion accuracy error caused by the system can be detected and measured separately, it contributes to the maintenance and inspection of the machine by properly pursuing and grasping the error factors of the machine motion accuracy.
Further, it is possible to improve the motion accuracy of the machine.

Further, according to the present invention, it is possible to set the radius R to a substantially zero value by the movement radius adjusting rod of the attitude control jig. High accuracy of measurement by detecting and measuring the roundness error, correcting the measurement data in the actual machine motion accuracy measurement process using the measured data as a correction, and removing the measurement value error from the machine motion accuracy measurement value. It has become possible to achieve this.

[Brief description of drawings]

FIG. 1 is a machine motion accuracy measuring device according to the present invention. A machine motion accuracy measuring device according to the present invention is provided between a first rotating shaft mounted on a machine spindle and a second rotating shaft mounted on a machine table. FIG. 7 is a vertical cross-sectional view showing a setting state in the case of inserting and performing a relative circular motion of a radius R between a main shaft and a table to measure motion accuracy.

FIG. 2 is a front view showing an embodiment in which a machine motion accuracy measuring device according to the present invention is configured by an attitude control jig and a tracing stylus.

FIG. 3 is a view showing an embodiment in which the machine motion accuracy measuring device according to the present invention is configured by an attitude control jig and a tracing stylus;
It is the side view seen from the line.

FIG. 4 is a side view seen from the line 4-4 in FIG.

FIG. 5 is a diagram showing the movement accuracy measuring apparatus shown in FIGS. 2 and 3, in which the posture control jig and the stylus are set so that the radius of the circular movement is zero, and the movement accuracy is measured. FIG. 6 is a front view showing a setting state when a roundness error can be measured.

FIG. 6 is a flow chart showing a measurement analysis process in the case where the motion accuracy measuring apparatus according to the present invention is used to measure the motion accuracy by applying a correction due to a circularity error of the measuring apparatus itself.

FIG. 7 is a front view showing another embodiment in which the motion accuracy measuring device for a machine according to the present invention comprises an attitude control jig and a displacement measuring means.

[Explanation of symbols]

 10 ... Posture control jig 12 ... Movement radius adjusting rod 14 ... Spacer member 16 ... Slide rod 20 ... Bracket 24 ... Measuring element 26 ... Screw shaft 26a ... Tip surface 30 ... Spindle 32 ... Table 40 ... First rotating shaft 60 ... Second rotary shaft 70 ... Displacement meter 70a ... Detecting end 80 ... Rotating motor 88 ... Belt / pulley mechanism 100 ... Displacement measuring meter 102 ... Measuring element

Claims (3)

[Claims] 1. A first rotary shaft mountable on a main shaft of a machine and a second rotary shaft mountable on a table of the machine, wherein an axial center distance between the main shaft and the table is a predetermined distance. relative 2 between the spindle and the table of setting to a value R
A motion accuracy measuring device for measuring motion accuracy of circular motion due to axial movement, wherein the device is mounted on one of the first and second rotary shafts and has a length in a radial direction of the circular motion. is formed on the movement radius adjusting rod and the movement radius adjusting rod integral to and uneven shape, the distance value R a slide rod that match engaged to be movable in the radial direction of the circular movement to the other rotary shaft to be set to any value including zero, the first radius relatively the distance value R in a posture always the same point facing around one of the rotating shaft and the other rotational shaft of the second rotary shaft And a slide of the attitude control jig mounted on one of the rotating shafts.
Before the contact point held at one end of the rod and the slide rod of the posture control jig are movably engaged
It is fixed to the other rotating shaft and cooperates with the probe to
Displacement measuring hand that generates measurement output according to radial displacement of circular motion
Mechanical motion accuracy measurement apparatus characterized by being configured by including a stage, a. 2. A first rotary shaft mountable on a main shaft of a machine and a second rotary shaft mountable on a table of the machine, wherein a predetermined axial distance is provided between the main shaft and the table. relative 2 between the spindle and the table of setting to a value R
A motion accuracy measuring device for measuring motion accuracy of circular motion due to axial movement, wherein the device is mounted on one of the first and second rotary shafts and has a length in a radial direction of the circular motion. is formed on the movement radius adjusting rod and the movement radius adjusting rod integral to and uneven shape, the distance value R a slide rod that match engaged to be movable in the radial direction of the circular movement to the other rotary shaft to be set to any value including zero, the first radius relatively the distance value R in a posture always the same point facing around one of the rotating shaft and the other rotational shaft of the second rotary shaft Before engaging the attitude control jig for performing the circular movement and the slide rod of the attitude control jig so that they can move.
Note: The probe fixed to the other rotating shaft and the slide of the attitude control jig attached to the one rotating shaft.
Displacement measuring means, which is held at one end of a rod and cooperates with the probe to generate a measurement output according to the radial displacement of the circular movement, and is configured to have a motion accuracy of the machine. measuring device. 3. The machine according to claim 1, further comprising a rotation driving means for rotating the first rotary shaft or the second rotary shaft at a constant speed when the distance value R is set to zero. Motion accuracy measuring device.