JPH0623642B2 - Straightness measuring instrument - Google Patents

Description

TECHNICAL FIELD The present invention relates to a straightness measuring instrument for measuring straightness and flatness of an object to be measured.

[Prior Art] Conventionally, as a method for measuring the straightness and flatness of an object to be measured, an autocollimator method and a comparison method with a reference straightedge are known.

First of all, the autocollimator method can measure with high accuracy because it is a measurement by reflected light of parallel rays of kagami, but it requires a large amount of auxiliary equipment, requires a long installation time, and is a two-point chain method. Since it is measured at, the calculation during the measurement is complicated. At present, calculation during measurement is performed by introducing a computer, but it still takes a long time to complete accurate measurement.

On the other hand, the comparison method does not require as much time as the autocollimator method, but it still requires a considerable amount of time, and it is unavoidable that the accuracy is deteriorated due to various conditions during the measurement. For example,
It takes time to combine the block gauges and change the height so that the scales of the pointer micrometer at both the start and end points of the measurement range become zero. When moving it, there is a risk of tipping over, the distance between the two block gauges must be measured while positioning with a tape measure, it takes time to set the measuring line on the surface to be used, and the automatic In the collimator and especially in the comparison method, it is necessary to put the object to be measured on the surface plate, and there are many occasions when the measuring instrument part related to the measurement is touched. For this reason, the measurement changes due to the temperature change.

In Japanese Utility Model No. 61-26111, side frames are provided at both ends, and sliding rods are provided between the side frames.
A surface strain measuring device is disclosed which measures the surface shape of the object under the side frame with reference to this sliding rod.

However, in the above-mentioned surface strain measuring machine, the accuracy of the sliding rod that is the reference and the deviation between the sliding rod and the measuring head directly affect the measuring precision. It needs to be created, and a device to eliminate the gap is required.

Further, since the sliding rod has no reference surface, it is difficult to determine what is the reference.

Japanese Utility Model Laid-Open No. 54-133870 discloses a flatness measuring instrument having a leg portion slidably supported on the lower surface of a spindle and a dial gauge slider slidably gripping the spindle. .

However, the legs are based on the lower surface of the support shaft,
Since the dial gauge slider is based on the upper surface of the support shaft, an error in the support shaft and the slider or a temperature change directly affects the measurement error. Therefore, a highly accurate and high quality support shaft and slider are required.

[Problems to be Solved by the Invention] The present invention eliminates the above-mentioned drawbacks and is simply configured by using an existing reference straight edge, and includes a lower reference surface of the reference straight edge and an upper surface of the object to be measured. Provided is a straightness measuring device which measures distance and measures straightness and flatness with high accuracy.

[Means for Solving the Problem] In order to solve this problem, the straightness measuring instrument of the present invention includes a reference straight edge and at least two slidably supporting the reference straight edge with the reference surface as a lower surface. One support leg, a carriage for slidably gripping the reference straightedge, a meter holder pressed against the lower surface of the reference straightedge by an elastic cushioning body by the carriage, and a holder held by the meterholder. Equipped with a meter, based on the lower surface of the standard straightedge,
The distance between the upper surface of the object to be measured placed under the supporting leg and the lower surface of the reference straight edge is sequentially measured by the meter corresponding to the sliding position of the carriage, and the straightness of the object to be measured is measured. It is characterized by measuring.

[Example] FIG. 1 (a) is an explanatory view showing straightness measurement by a conventional comparison method, in which 1 is an object to be measured, 2 is two block gauges placed on the object to be measured, and 3 is a block gauge. Is 2 block gauges 2
The reference straight edge ruler placed on the upper side, 4 is a stand that can slide in the longitudinal direction on the use surface of the reference straight edge ruler, and 5 is a pointer micrometer for reading the deviation at each measurement point of the measured object.

The procedure of straightness measurement by this configuration will be described according to the procedure flow chart of FIG. 1 (b).

First, in step S1, the DUT 1 is moved onto the surface plate for measurement. Next, at step S2, the block gauge 2
, And the reference straight ruler 3 is installed on the block gauge 2 in step S3. In FIG. 1 (a), when the measurement is performed along a line extending from the front side to the back side of the DUT 1, the step S is performed.
Install the stand 4 at one end of the measurement line at step 4,
Adjust the scale of the pointer micrometer 5 to zero with 5-6. In step S7, the stand 4 is moved to the other end of the measuring line, and in step S8 it is checked whether the scale of the pointer / micrometer 5 is zero. Here, the height of the block gauge is changed so that the scale of the pointer micrometer 5 becomes zero at both ends of the measurement range start point and end point, and steps S2 to S8 are repeated. Next, in step S9, the distance to the next measurement point is measured, in step S10, the stand 4 is moved along the use surface of the reference straight edge ruler 3, and in step S11 it is checked whether or not the predetermined interval is present. If it is a predetermined interval, the scale of the pointer micrometer 5 is read in step S12. In step S13, it is checked whether or not the measurement up to the end point is completed, and steps S9 to S13 are repeated until the end.
After the end, in step S14, the pointer micrometer 5 at both ends again.
Check if the scale is zero and if it is not zero, step S2
Start over. If it is zero, the straightness measurement is completed, and the object to be measured is moved to the work table in step S15 to complete the entire process. Then, the mutual difference in height of the measurement points measured along the measurement line of the used surface is the calculated straightness. The flatness is obtained by calculation based on the mutual difference of the heights of the respective measurement points on the measured line.

FIG. 2 (a) is a perspective view of a straightness measuring instrument according to an embodiment of the present invention. The straightness measuring device 20 is composed of a reference straight ruler 21 made of alumina ceramics supported by two supporting legs 22 movable in the longitudinal direction X, and a measuring section 30. The height of the support leg 22 can be finely adjusted by the fine adjustment knob 22a. The measuring section 30 includes a carriage 23 for sliding on the reference straight edge 21 in the longitudinal direction X, a meter holder 24 for making a reference surface for measurement a lower surface 28 of the reference straight edge 21, and a pointer measuring as a meter. It is composed of a fine instrument 25. The pointer micrometer 25 has a zero correction knob 25a.
There is. The lower side surface 27 of the reference straight edge ruler 21 is used to prevent lateral shake of the meter holder 24. In addition, the scale 26 is attached to the side surface of the reference straight edge ruler 21 to support the support leg 22.
Also, the positioning of the measuring unit 30 is convenient. Since the straightness measuring device 20 is installed on the object to be measured 29 as shown in FIG. 2 (a), it is not necessary to replace the object to be measured 29 on the surface plate, and the work piece is measured on the table of the machine. Is possible. Also, since each part is integrated, it can be carried by one person, and it does not take time and effort for installation.

Here, the measurement procedure will be described according to the procedure flow chart of FIG. First, in step S21, the two support legs 22 of the straightness measuring device 20 are moved and fixed to both ends of the object 29 to be measured or to an arbitrary position to be measured. Next, in step S22, the straightness measuring device 20 is installed so that the two support legs 22 are placed on the object 29 to be measured.

In step S23, the measuring unit 30 is moved to one end, and in step S24-25, the zero correction knob 25a of the pointer micrometer 25 is moved.
Turn to set the pointer to zero.

In step S26, the measuring unit 30 is moved to the other end, and in step S27-28, if the pointer is zero or if it is not zero after checking, the pointer is adjusted to zero by the fine adjustment knob 22a of the support leg 22. To do. When both hands become zero at both ends, the measurement is ready. The fine adjustment was performed by attaching an eccentric member (not shown) to the tips of the supporting legs, but other known methods may be used.

In step S29-30, while moving the measuring unit 30 on the reference straight edge ruler 21 by looking at the scale 26 by a predetermined distance in the X direction, the pointer value is measured in step S31. If the measurement value is positive, the measurement point of the object 29 to be measured is convex from both ends, and if the measurement value is negative, it is concave from both ends. In step S32, it is checked whether or not the measurement up to the end point has been completed, and steps S29 to S32 are repeated until the end. After the measurement is completed, it is confirmed that the pointers at both ends are zero again, and the whole measurement process is completed. Here, the lower surface 28 of the reference straight edge ruler 21 serves as a reference for the pointer, so that the distance between the point to be measured and the reference point is small, and the influence of flaws and the like on each part is small and highly accurate measurement is possible.

Next, referring to FIGS. 3 and 4 (a) and (b), the structure of the measuring unit 30 will be described because the measurement reference is the lower surface 28 of the reference straightedge 21. FIG. 3 is an explanatory view of the measuring unit 30 when viewed from the front, FIG. 4 (a) is an installation explanatory view of the carriage 23, and FIG. 4 (b) is an installation explanatory view of the meter holder 24.

The carriage 23 is installed on the reference straight edge 21 by means of a bearing 31 attached to the tip of the shaft 32, and moves smoothly on the reference straight edge 21 in the longitudinal direction X. The bearing 31 is a standard straight-edge ruler 21 for smooth movement.
There is some swaying in the carriage 23 that is not in close contact with.
The shaft 32 is eccentric to adjust the ease of movement of the carriage 23. Twelve bearings 31 are installed so as to hit the upper, lower, left and right sides of the reference straightedge 21.

The meter holder 24 is not directly connected to the carriage 23, so that the shaking of the carriage 23 is not transmitted to the meter holder. The meter holder 24 is brought into contact with the reference straight-edge ruler 21 by means of six contacts 33 made of Teflon resin having a small friction, and the carriage 23 to the four springs 3 are contacted.
The lower surface and the side surface are pressed against the reference straight edge ruler 21 at 4. The pointer micrometer 25 is fixed to the meter host 24, and is separated from the carriage 23 except for the spring 34.

Here, considering the movement of the measurement unit 30, the carriage 23
Is supported by a bearing 31 and moves on the reference straightedge 21. On the other hand, the meter holder 24 is moved by the spring 34 with reference to the lower surface 28 and the side surface 27 of the reference directing device 21,
The sway of the carriage 23 does not affect the meter holder 24, in other words, the pointer micrometer 25 at all.
Highly accurate measurement can be performed with reference to the lower surface 28 of 1. still,
The carriage 23 that touches the hand is made of a heat insulating material and prevents the meter holder 24 from being affected by heat.

Further, the straightness measuring device 20 of this embodiment has the following features. FIG. 5A shows the handle 51 installed on the upper portion of the support leg 22. By installing this handle 51, it is possible to easily carry it and prevent the reference straight ruler 21 from being touched. As shown in FIG. 55 (b), an arm 22 a is formed at the lower end of the support leg 22 to form an L shape, which enables the measuring section 30 to move to both ends of the object 29 to be measured. Further, the contact point portion 52 of the support leg 22 with the measured portion 29 is made a part of a sphere to prevent the wheel from being finely adjusted during the measurement. FIG. 5C shows the straightness measuring device 20.
The plate 54 is shown to prevent the tumbling. Furthermore,
The claw 53 is provided, and the tip of the claw 53 indicates the position where the tip of the pointer micrometer 25 contacts the object to be measured 29. or,
In order to correct the deflection of the standard straightedge, it may be possible to make the lower surface a concave curved surface. The material of each part including the standard straightedge is not limited as long as the invention can be achieved. Next, the straightness measuring device 2 of this embodiment
An example of the flatness measuring device of FIG. 6 using 0 will be described.

Here, the meter is the electric micrometer 70, and the measuring unit 71 freely receives the signal from the position control output unit 67 through the cable 67 in the longitudinal direction X. Again 2
The two support legs 72 are also moved in the direction Y perpendicular to the longitudinal direction and finely adjusted in height through the cable 67.
It receives the signal from 7 and is controlled. On the other hand, the output signal of the electric micrometer 70 and the position signal of the measuring unit 71 are transmitted from the signal input unit 66 to the flatness measurement control unit 6 through the cable 68.
It is input to 0 as digital data. Flatness measurement control unit 6
In 0, according to the program stored in the ROM 62,
While controlling the movement of the straightness measuring device 20 through the position control output unit 67, the RAM 63 stores the measured values at each point of the measured object 73. From the stored measured values, various arithmetic processing for expressing the flatness is performed, and numerical values and drawings are output to the display device (hereinafter CRT) 64 and the printer (hereinafter PRT) 65.

The flow chart of the flatness measurement program is shown in FIG. First, in step S71, the carriage 71 is moved in the longitudinal direction X, and an initial value for automatically adjusting the support leg 72 so that the output of the electric micrometer 70 has the same value at the left and right ends is set. In step S72, the straightness measuring instrument is set. Set 20 to the start position.

The position data of the measuring unit 71 is input in step S73, and the reading of the electric micrometer 70 is input in step S74. In step S75, the position data input in step S73 is used as an address, and the reading of the electric micrometer 70 input in step S74 is stored in the RAM 63.
In step S76, the measuring unit 71 is moved in the longitudinal direction X by a certain distance.
To check the end of measurement in the longitudinal direction at step S77, and if not, repeat steps S73 to S77.

When the measurement in the longitudinal direction X is completed, the process goes from step S77 to step S78 to automatically move the support leg 72 of the straightness measuring device 20 and move to the next straightness measuring position. Step S
At 79, check whether the measurement of all areas of the DUT 73 has been completed, and if not, return to step S73,
Repeat steps S73-79.

When the measurement of all areas is completed, from step S79 to step S80, various arithmetic processing for expressing the flatness is performed, and in step S81 the CRT 64 is displayed, and in step S82, it is printed on the PRT 65 and the flatness measurement is completed. Becomes

[Effect of the Invention] According to the present invention, the straightness can be configured with high accuracy by using the existing standard straightedge and simply measuring the distance between the reference surface of the lower surface of the standard straightedge and the upper surface of the object to be measured. A straightness measuring device for measuring flatness can be provided.

[Brief description of drawings]

FIG. 1 (a) is an explanatory view of straightness measurement by a conventional comparison method, FIG. 1 (b) is a flow chart of a conventional straightness measurement procedure, and FIG. 2 (a) is a straightness measuring instrument of this embodiment. FIG. 2 (b) is a flow chart of the straightness measurement procedure of the present embodiment, FIG. 3 is an explanatory view of the measuring section as seen from the front, and FIG. 4 (a) is an explanatory view of installation of a carriage. 4 (b) is an explanatory view of the installation of the meter holder, FIG. 5 (a) is a schematic top view of the support leg, FIG. 5 (b) is a schematic side view of the support leg, and FIG. 5 (c) is a schematic view of the support leg. FIG. 6 is a block diagram of a flatness measuring device using the straightness measuring device of this embodiment, and FIG. 7 is a flow chart of a measuring program of the flatness measuring device. In the figure, 20 ... Straightness measuring instrument, 21 ... Standard straightedge, 2
2 ... Support leg, 22a ... Support leg fine adjustment knob, 23 ...
... Carriage, 24 ... Meter holder, 25 ... Pointer micrometer, 25a ... Zero correction knob, 26 ... Scale, 2
7: lower side surface of the reference straightedge, 28: lower surface of the reference straightedge, 29: object to be measured, 30: measurement part.

Claims (9)

[Claims] 1. A reference straight edge, at least two support legs slidably supporting the reference straight edge with a reference surface as a lower surface, a carriage for slidably gripping the reference straight edge, and the carriage. Therefore, it is provided with a meter holder that is pressed against the lower surface of the reference straight ruler via an elastic cushioning body and a meter held by the meter holder, and is placed under the support leg with the lower surface of the reference straight ruler as a reference. The distance between the upper surface of the measured object and the lower surface of the reference straightedge,
A straightness measuring instrument, characterized in that the straightness of the object to be measured is sequentially measured by the meter corresponding to the sliding position of the carriage. 2. The straightness measuring device according to claim 1, wherein at least one of the support legs is capable of finely moving up and down. 3. The straightness measuring instrument according to claim 2, wherein the cut surface of the support portion on the object to be measured of at least one of the support legs is substantially a part of a circle. 4. The support leg is L-shaped, and the entire width of the measurement target can be measured by placing the support leg on the object to be measured. The straightness measuring instrument described in the item. 5. The straightness measuring instrument according to claim 1, wherein the meter is a pointer micrometer. 6. The straightness measuring instrument according to claim 1, wherein the meter is an electric micrometer. 7. The support leg according to claim 1, wherein a side surface of the support leg has a plate having a length sufficient to prevent the straightness meter from falling in a direction substantially perpendicular to the longitudinal direction. Straightness measuring instrument. 8. The straightness measuring instrument according to claim 1, wherein a scale for positioning the support leg is attached to at least one side surface of the reference straight edge ruler. 9. The lower surface of the reference straightedge is formed to have a concave central portion in order to compensate for a deflection caused by the movement of the carriage. A straightness measuring instrument according to the first item of the range.