JP2980509B2 - Straightness 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 straightness measuring device for measuring the straightness of, for example, the surface of a large roll or the surface of a sheet material.

[0002]

2. Description of the Related Art Conventionally, as a device for measuring the straightness of the surface of a large roll or the surface of a plate material, for example, there are a laser measuring device, an autocollimator, a level, and a guide type measuring device.

[0003] A laser measuring device utilizes the straightness of a laser beam. A target is placed on a measurement surface, a target is irradiated with a laser beam, and a light receiving position of the irradiated laser beam is detected. Thus, straightness is detected.

[0004] The autocollimator is a surveying instrument using parallel rays, and measures the displacement of a target placed on the surface to be measured with the naked eye. In addition, when using a level, the straightness is measured by moving the level at a constant pitch along the surface to be measured and continuously combining the inclination angles at each measurement point. is there.

Further, in the guide type measuring device, a carriage having a displacement sensor attached to a reference guide rail is movably provided, and the carriage is moved on the surface to be measured, thereby measuring the straightness of the surface to be measured. It was done. Further, according to the guide measuring instrument, when the measurement length is longer than the measurable range of the measuring instrument, the measurement is performed while shifting the guide measuring instrument so that the measuring range partially overlaps. I was

[0006]

However, according to the laser measuring instrument and the autocollimator described above, it is usually difficult to automate the target because it is necessary to manually move the target on the surface to be measured. According to this method, there is a disadvantage that the measurement pitch cannot be made fine. Furthermore, according to the above-mentioned guide type measuring instrument, when the measurement length is long, it is necessary to move the reference guide rail and move it so that a part thereof is overlapped to perform the measurement. There is a problem that the surface cannot be measured with high accuracy over the entire length. It is sufficient that the reference guide rail is made longer according to the length of the surface to be measured. However, a guide rail that is long and has good straightness is very expensive.

Therefore, an object of the present invention is to provide a straightness measuring device which can solve the above-mentioned problem.

[0008]

In order to solve the above-mentioned problems, a straightness measuring apparatus according to the present invention is provided with a gantry provided on a surface to be measured and provided with a first guide member along a predetermined direction. A first moving body guided by the first guide member and made movable by the first moving device; and provided on the first moving body and provided in parallel with the first guide member. Second guide member, and the second
A second moving body guided by the guide member and made movable by the second moving device; a distance sensor provided on the second moving body for measuring a distance to a surface to be measured; The displacement of the surface to be measured is obtained by inputting the measurement signal value, and when a part of the surface to be measured is overlapped and measured by the distance sensor during the movement of the second movable body, the overlap portion is measured. The measurement value is obtained as an approximate curve by the least square method, and the arithmetic control unit corrects the entire measured value so that the approximate curves of the overlapped portion overlap each other.

[0009]

According to the above arrangement, the second device having the distance sensor is provided.
The movable body is moved in a parent-child manner, the measurable range of the second movable body is partially overlapped and measured, and the measured distance obtained by the overlap is determined using the least squares method.
The measurement distances over the entire surface to be measured, that is, the displacements with respect to the surface to be measured are determined so as to coincide with each other. Therefore, straightness can be accurately measured over the entire surface to be measured.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. 1 and 2, reference numeral 1 denotes a straightness measuring device according to the present invention, in which a mounting leg plate portion 2a is attached to both ends and a first guide rail (first guide member) 3 is formed in a horizontal direction. Guide frame 2 and this first
Between a first moving body 5 that is movably guided in a horizontal direction via a pair of slide members 4 that engage with the guide rail 3, and a support plate 5a protruding from both ends of the first moving body 5. A second guide rail (second guide member) 6 provided in parallel with the first guide rail 3;
And a distance sensor (also referred to as a displacement sensor, which is also referred to as a displacement sensor, attached to the second moving body 7 and configured to measure a distance to a surface to be measured. Eddy current type, capacitance type is used)
8 and the first moving body 5 provided on the guide base 2 side.
, A second moving device 12 provided on the first moving body 5 side for moving the second moving body 7, and a control device for controlling these moving devices 11 and 12 ( (Not shown, for example, a computer is provided) and a measurement signal from the distance sensor 8 is input to obtain a measurement distance (displacement of the surface to be measured). When a part of the surface to be measured is measured by the sensor 8 in an overlapping manner, the measured distance of the overlapping portion is obtained as an approximate curve by the least square method, and the approximate curves of the overlapping portion overlap each other. And a calculation control unit (not shown, for example, having a computer) for correcting the measurement distance over the entire surface to be measured.

As the distance sensor 8, there is a contact type or a non-contact type. In the case of the contact type, a linear encoder type is used. In the case of the non-contact type, an eddy current type is used. , An optical type, or an air sensor is used.

A linear guide system (LM) is used as a slide mechanism of each of the moving bodies 5 and 7 with respect to each of the guide rails 3 and 6. Further, the first moving device 11 includes a male screw body 21 provided on the upper surface of the guide base 2 in parallel with the first guide rail 3 so as to be rotatable, and a male screw body provided at an end of the guide base 2. It comprises a first motor 22 for rotating the body 21 and a nut body 23 screwed to the male screw body 21 and fixed to the first moving body 5 side. In addition, a ball screw mechanism is employed for engagement between the male screw body 21 and the nut body 23, and smooth movement of the first moving body 5 is ensured. Of course, a normal screw mechanism may be used.

The second moving device 12 is wound around a driving pulley 25 and a driven pulley 26 provided at both ends of the second guide rail 6, and is wound around these pulleys 25, 26. Both ends are the second moving body 7
And a second motor 28 that is attached to the second guide rail 6 and rotates the drive pulley 25.

Therefore, by rotating the first motor 22, the first moving body 5 can be moved in the horizontal direction, and by rotating the second motor 28,
The distance sensor 8 attached to the second moving body 7 can be moved in the horizontal direction with respect to the first moving body 5. That is, the distance sensor 8 is moved in two steps in a parent-child manner.

The second guide rail 7 for guiding the second moving body 7 is made of ceramic and has an accuracy such that the straightness is 5 to 10 μm or less for a length of 1000 to 1500 mm, for example. It is made with.

A case of measuring the straightness of a surface to be measured longer than the length of the second moving body 7 in the above configuration will be described with reference to FIG. Surface to be measured (for example, roll surface)
Assuming that the distance of the measurement range is L and the distance of the range that can be measured by the second moving body 7 is M, for example, the measurement is performed in three steps as shown in FIG.

[0017] That is, dividing the measurement range into three and M _1, M _2, M _3, yet a part of the measurement range adjacent to each other (m
₁ , m ₂ ) are overlapped. Then, in each of these measurement ranges (M ₁ , M ₂ , M ₃ ),
By moving the second moving body 7, the distance to the surface to be measured is measured in each range.

Next, each measurement distance in the overlap portion (m ₁ , m ₂ ) of each measurement range is approximated by the least squares method, and an approximate curve is obtained. Then, the curves obtained by the measurement distances are made to match so that the approximate curves on both sides in the adjacent measurement ranges overlap each other, that is, over the whole.

Thus, the overlap portion (m ₁ ,
m ₂ ) was approximated by the method of least squares, and the approximated curves were overlapped with each other.
In order to cope with the case where the straightness of the first guide rail 3 is not good, that is, when the straightness of the first guide rail 3 is not good, the overlap portions (m ₁ , m ₂₎ measured in the respective measurement ranges. This is because the measurement distance (displacement on the surface to be measured) does not always match.

Thus, the overlap portion (m ₁ ,
m ₂ ), the measurement distance (displacement on the surface to be measured)
By superimposing them so that they coincide with each other, straightness can be accurately obtained over the entire surface to be measured.

Further, according to this configuration, the straightness accuracy of the second guide rail 7 which can be shorter than the first guide rail 3 may be maintained satisfactorily, and the straightness of the first guide rail 3 itself may be maintained. Since the accuracy does not have to be good, it can be manufactured relatively inexpensively.

[0022]

As described above, according to the structure of the present invention, the second movable body having the distance sensor is moved in a parent-child manner, and the measurable range of the second movable body is partially overlapped and measured. In addition, the measurement distances obtained by the overlap are corrected by the least squares method so as to match each other, and the measurement distance over the entire surface to be measured, that is, the displacement with respect to the surface to be measured, is obtained. However, straightness can be accurately measured over the entire surface to be measured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic overall configuration of a straightness measuring device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a main part of a straightness measuring device in the embodiment.

FIG. 3 is a diagram illustrating a method of measuring straightness in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Straightness measuring device 2 Guide stand 3 First guide rail 4 Slide member 5 First moving body 6 Second guide rail 7 Second moving body 8 Distance sensor 11 First moving device 12 Second moving device

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) G01B 21/00-21/32 G01B 5/00-5/30

Claims (1)

(57) [Claims] 1. A gantry provided with a first guide member provided on a surface to be measured and provided along a predetermined direction, and a first moving device guided by the first guide member. A movable first movable body, a second guide member provided on the first movable body and provided in parallel with the first guide member, and a second movable body guided by the second guide member A second movable body movable by the device, a distance sensor provided on the second movable body for measuring a distance to a surface to be measured, and a measurement signal value input from the distance sensor to receive a measurement on the surface to be measured. When a part of the surface to be measured is measured by the distance sensor while the second moving body is moving while the second moving body is moving, the measured value of the overlapped portion is approximated by an approximation curve by the least square method. Asking for The overlap portion approximated to the curve overlap each other, the entire measurement straightness measuring apparatus characterized by being configured from a calculation control unit that corrects.