JP2024107594A - Measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure dimensions of a cylindrical measurement target.

SOLUTION: A measuring apparatus 1 includes: a first measuring device 10 including a transmission type laser measuring instrument configured such that a light projector 12 and a light receiver 13 are disposed across an end measurement position 95 being a position in a part of a circumference of one end of a cylindrical measurement target 90 so as to measure the end measurement position 95, the first measuring device being configured to output a first signal indicative of the end measurement position 95; and a calculation device 82 configured to calculate a length from a reference position to the end measurement position 95 of the measurement target 90 based on the first signal.

SELECTED DRAWING: Figure 1A

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a measuring device.

For example, the can manufacturing process includes many processing steps. Each processing step is checked to ensure that the processing is performed appropriately. For example, an inspection is performed in which a worker periodically extracts cans from the middle of the production line and measures the dimensions of the cans during production. Patent Document 1 discloses efficient inspection to detect defective cans early and remove them from the production line. This document discloses a measuring device and a rejection device that are installed in a trimming device that performs trimming after drawing and ironing, and that measure the can height dimensions and reject cans whose dimensions are outside the allowable range. As in the above example, in the manufacturing process of goods, it is necessary to measure various dimensions to judge the quality of the processing and the product.

Japanese Patent Application Publication No. 5-318006

The purpose of the present invention is to measure the dimensions of a cylindrical measurement object.

According to one aspect of the present invention, the measurement device includes a transmission type laser measurement device configured to arrange a light projector and a light receiver on either side of an end measurement position, which is a position of a portion of the circumference of one end of a cylindrical measurement object, and is equipped with a first measurement device configured to output a first signal indicating the end measurement position, and a calculation device configured to calculate the length from a reference position of the measurement object to the end measurement position based on the first signal.

In the above-mentioned measuring device, the light projector may be configured to irradiate the laser light in a band-like parallel manner at an angle with respect to a plane formed including the one end of the object to be measured.

In any of the above measuring devices, the light projector and the light receiver may be arranged outside the object to be measured, sandwiching the entire object to be measured.

Any of the above measuring devices may further include a calibration member arranged at a known position, and the known position of the calibration member may be a position that blocks a part of the laser light irradiated from the projector when the measurement object is not present at a measurable position where the first measuring device can identify the end measurement position, and is not hit by the laser light irradiated from the projector when the measurement object is present at the measurable position because it is blocked by the measurement object.

In any of the above measuring devices, the first measuring device may be configured to output a second signal indicating the position of the end of the calibration member at least once when the measurement object is not present at the measurable position, and the calculation device may be configured to perform a calibration calculation based on the second signal when calculating the length.

In any of the above measuring devices, the calibration member may include a plurality of calibration elements fixed at different known positions corresponding to a plurality of types of the measurement object, and the light projector and the light receiver may be configured to be movable to different positions corresponding to a plurality of types of the measurement object.

Any of the above measuring devices may further include a second measuring device configured to measure a side measurement position, which is a part of the side of the measurement object, and output a third signal indicating the side measurement position, and the calculation device may be configured to perform a calibration calculation using the third signal when calculating the length, or to determine whether or not it is necessary to calculate the length based on the third signal.

In any of the above measuring devices, the end measurement position and the side measurement position may be located in the same plane that includes the axis of the measurement object.

In any of the above measuring devices, the second measuring device may include a through-beam type laser measuring device configured such that a light projector and a light receiver are disposed outside the measurement object with the side measurement position in between.

In any of the above measuring devices, the light projector may be configured to irradiate a band of laser light parallel to a surface formed including the one end of the object to be measured, and one of the light projector and the light receiver may be arranged inside the object to be measured, and the other of the light projector and the light receiver may be arranged outside the object to be measured.

Any of the above measuring devices may further include a rotation device configured to rotate the measurement object around the axis of the measurement object, the first measuring device may be configured to identify multiple end measurement positions on one of the measurement objects, and the calculation device may be configured to calculate lengths from multiple reference positions to the end measurement positions on one of the measurement objects.

In any of the above measuring devices, the computing device may be configured to determine whether or not there is a step around one end of the object to be measured.

Any of the above measuring devices may further include a transport device configured to transport the multiple measurement objects sequentially to a measurement position where the first measuring device can identify the end measurement position, the first measuring device configured to sequentially identify the end measurement positions of the multiple measurement objects, and the calculation device configured to calculate the lengths of the multiple measurement objects and analyze the differences in the lengths of the multiple measurement objects.

In any of the above measuring devices, the arithmetic device may be configured to analyze the state of the material of the object to be measured or the state of the processing device that processed the object to be measured based on the difference in length.

In any of the above measuring devices, the measurement object may be a can that has been trimmed after drawing and ironing in a can manufacturing process.

According to one aspect of the present invention, the measurement method includes positioning a cylindrical object to be measured such that an end measurement position, which is a part of the circumference of one end of the object, is located between a light projector and a light receiver of a transmission type laser measurement instrument, measuring the end measurement position with the laser measurement instrument, obtaining a first signal indicating the measurement result of the end measurement position, and calculating the length from a reference position of the object to the end measurement position based on the first signal.

According to one aspect of the present invention, a method for manufacturing a can includes the above-described measurement method.

The present invention makes it possible to measure the dimensions of a cylindrical measurement object.

FIG. 1A is a schematic front view illustrating an outline of a configuration example of a measurement device according to one embodiment. FIG. 1B is a schematic right side view illustrating an outline of a configuration example of a measurement device according to one embodiment. FIG. 1C is a schematic plan view illustrating an outline of a configuration example of a measurement device according to an embodiment. FIG. 2A is a diagram for explaining measurement by the first measuring device, and is a front view showing a state in which a measurement object is placed on a turntable and laser light is blocked. FIG. 2B is a diagram for explaining measurement by the second measuring device, and is a plan view showing a schematic state in which the measurement object is placed on the turntable and the laser light is blocked. FIG. 3 is a diagram for explaining a state when the measurement object is distorted. FIG. 4 is a diagram for explaining a method for deriving the height of a measurement object. FIG. 5 is a diagram illustrating a schematic configuration of a first measuring device according to a first modified example.

One embodiment will be described with reference to the drawings. This embodiment relates to a measuring device and a measuring method for measuring the length from a reference position to one end of a cylindrical measuring object. The measuring object is, for example, a trimmed can obtained in the middle of a can manufacturing process. Here, the trimmed can is, for example, a can in a state in which a cup punched out of a plate material such as an aluminum alloy is drawn and ironed to trim the open end. The trimmed can has a cylindrical shape with a bottom. The plate thickness of the trimmed can is, for example, about 0.1 mm. The length measured by the measuring device is, for example, the height of the trimmed can. Therefore, this measuring device can be used in the manufacture of cans, and this measuring method can be used in the manufacture of cans. The measuring device of this embodiment is not limited to this, and can also be used to measure cylindrical objects of various shapes.

[Configuration of measuring device]
Fig. 1A is a schematic front view showing an outline of a configuration example of a measurement device 1 according to the present embodiment. Fig. 1B is a schematic right side view showing an outline of the configuration example of the measurement device 1. Fig. 1C is a schematic plan view showing an outline of the configuration example of the measurement device 1.

In the measuring device 1, the measurement is performed when the measurement object 90 is in the position shown by the two-dot chain line in the figure. That is, the measurement is performed in a state where the measurement object 90 is fixed on the horizontal disk-shaped rotating table 71 of the rotating device 70 with its central axis facing vertically. The position of the measurement object 90 when the measurement is performed is referred to as the measurable position. As an example, the bottom of the measurement object 90 is recessed in a dome shape. The rotating device 70 fixes the measurement object 90 on the flat rotating table 71 by sucking air from the dome part of the bottom of the measurement object 90 through a hole (not shown) provided in the rotating table 71. The measurement object 90 is fixed at a position where its central axis coincides with the center of the rotating table 71. The method of fixing the measurement object 90 to the rotating table 71 is not limited to the method exemplified here, and any method may be used.

The measuring device 1 is configured to measure the height of the upper end of the measuring object 90. The upper end of the cylindrical measuring object 90 is trimmed to a circular shape. The measuring device 1 is configured to measure an end measurement position 95, which is one position on the circumference. In other words, the measuring device 1 is configured to measure the height from the rotating table 71 to the end measurement position 95.

The rotating table 71 of the rotating device 70 is configured to rotate around the central axis of the disk by the motor 72. That is, the rotating device 70 rotates the measurement object 90 around its central axis. Therefore, the measuring device 1 can measure the height of each position on the circumference of the upper end of the measurement object 90 as the end measurement position 95.

The measuring device 1 is equipped with a first measuring device 10, which is a laser measuring device of a transmission type, for measuring the end measurement position 95. The first measuring device 10 has a projector 12 and a receiver 13. The projector 12 is configured to irradiate a laser beam 16 in a parallel band shape. The receiver 13 is configured to receive the laser beam 16. The receiver 13 is configured to detect the width and position of the received band-shaped laser beam 16. The projector 12 and the receiver 13 are provided so as to face each other across the end measurement position 95. In this embodiment, the projector 12 and the receiver 13 are arranged outside the measurement object 90, sandwiching the entire measurement object 90 between them. In addition, as described in detail later, the projector 12 and the receiver 13 are arranged so that the band-shaped laser beam 16 is located in a vertical plane and the traveling direction of the laser beam is slightly inclined from the horizontal so that the first measuring device 10 can detect the vertical position.

The measuring device 1 includes a calibration member 30 arranged to block a small portion of the band-shaped laser light 16. The calibration member 30 is, for example, a block gauge. The calibration member 30 is fixed at a known position. When the measurement object 90 is not on the rotating table 71, the calibration member 30 blocks a portion of the laser light 16, but when the measurement object 90 is on the rotating table 71, the calibration member 30 is fixed at a position where the measurement object 90 blocks a portion of the laser light 16 and the laser light 16 does not hit the calibration member 30.

The measuring device 1 is equipped with a second measuring device 40, which is a transmission type laser measuring device, for measuring the position of the side of the measuring object 90 below the end measurement position 95 of the measuring object 90. The second measuring device 40 has a light projector 42 and a light receiver 43. The light projector 42 is configured to irradiate a laser beam 46 in a parallel band shape. The light receiver 43 is configured to receive the laser beam 46. The light receiver 43 is configured to detect the width and position of the received band-shaped laser beam 46. The light projector 42 and the light receiver 43 are provided so as to face each other across the side of the measuring object 90. The light projector 42 and the light receiver 43 are arranged so that the band-shaped laser beam 46 is located in a horizontal plane so that the second measuring device 40 can detect the horizontal position.

The measuring device 1 includes a conveying device 60 that conveys the measurement object 90 to the turntable 71 of the rotating device 70 and removes the measurement object 90 from the turntable 71 after measurement. The conveying device 60 includes a first conveying device 61, a second conveying device 62, and a third conveying device 63. The second conveying device 62 has an arc-shaped conveying table 621 that is installed horizontally. The turntable 71 is installed without any steps midway on the conveying table 621. The second conveying device 62 has a conveying arm 622 that rotates horizontally by a motor 623. The measurement object 90 is pushed and conveyed by the conveying arm 622 that rotates on the arc-shaped conveying table 621.

The first conveying device 61 is, for example, a belt conveyor. The first conveying device 61 conveys the upright measurement object 90 from outside the measuring device 1 in a horizontal direction into the measuring device 1. The measurement object 90 conveyed by the first conveying device 61 is transferred to the second conveying device 62. The second conveying device 62 conveys the measurement object 90 to a measurable position on the turntable 71 for measurement. The third conveying device 63 is, for example, a belt conveyor. The measurement object 90 measured on the turntable 71 is conveyed by the second conveying device 62 and transferred to the third conveying device 63. The third conveying device 63 conveys the upright measurement object 90 from inside the measuring device 1 in a horizontal direction out of the measuring device 1.

The measuring device 1 includes a computer 80. The computer 80 includes various integrated circuits and the like. The computer 80 functions as a control device 81 and an arithmetic device 82. The control device 81 controls the operation of each part of the measuring device 1. The arithmetic device 82 acquires measurement data from the first measuring device 10 and the second measuring device 40, and performs various analyses. The arithmetic device 82 calculates, for example, the height from the top surface of the turntable 71 of the measurement object 90 to the end measurement position 95 based on the signal output from the first measuring device 10.

[About acquiring measurement signals]
Measurement by the first measuring device 10 will be described. The projector 12 irradiates a parallel band of laser light. The receiver 13 receives the laser light irradiated from the projector 12. The measurement object 90 is disposed between the projector 12 and the receiver 13 so as to block a portion of the band-like laser light 16. The receiver 13 detects the laser light 16 that reaches the receiver 13 out of the band-like laser light 16, and can output a signal indicating the size, position, etc. of the measurement object 90 that blocks the laser light 16.

Figure 2A is a diagram for explaining measurement by the first measuring device 10, and is a front view showing a state in which a measurement object 90 is placed on a rotating table 71. As shown in Figure 2A, the light projector 12 and the light receiver 13 are arranged so that the band-shaped laser light 16 is located in a vertical plane. The light projector 12 and the light receiver 13 are arranged so that a portion of the band-shaped laser light 16 is blocked by the upper end of the measurement object 90. In addition, the light projector 12 and the light receiver 13 are arranged so that the traveling direction of the laser light 16 is slightly tilted with respect to the horizontal, that is, with respect to a plane formed including the upper end of the measurement object 90.

Due to this arrangement, part of the lower side of the band-shaped laser light 16 emitted from the projector 12 is blocked by the outer peripheral surface of the object 90 on the projector 12 side. The part of the laser light 16 above the upper end 90a of the object 90 on the projector 12 side passes through and proceeds. The part of the band-shaped laser light 16 that is not blocked by the side of the object 90 on the projector 12 side is blocked by the inner peripheral surface of the object 90 on the receiver 13 side. The part of the laser light 16 above the upper end 90b of the object 90 on the receiver 13 side passes through and proceeds further to reach the receiver 13.

If there is no measurement object 90, the receiver 13 can detect the laser light 16 in the area 17a where all of the laser light 16 irradiated from the projector 12 reaches. The receiver 13 detects the laser light 16 only in the area 17b where the laser light 16 that is not blocked by the presence of the measurement object 90 reaches. The receiver 13 outputs a detection result signal indicating the edge position between the position on the receiver 13 where the laser light reaches and is detected and the position where the laser light is blocked and not detected. The detection result signal is transmitted to the computer 80. Based on the detection result signal obtained from the receiver 13, the computer 80 determines the length from the reference position of the measurement object 90 to the position of the upper end 90b of the measurement object 90 on the receiver 13 side, that is, the end measurement position 95, as described below. If this reference position is the lowest part of the measurement object 90, that is, the upper surface of the rotating table 71, the computer 80 determines the height of the measurement object 90. The reference position may be set anywhere.

In this embodiment, the first measuring device 10 is installed at an angle to the horizontal. If the first measuring device 10 were installed horizontally, the higher of the upper end 90a on the projector 12 side of the measurement object 90 and the upper end 90b on the receiver 13 side would be measured by the first measuring device 10. In this embodiment, the projector 12 and receiver 13 of the first measuring device 10 are installed at an angle to ensure that the upper end 90b on the receiver 13 side of the measurement object 90 is the end measurement position 95.

The measuring device 1 rotates the measurement object 90 around its axis using the rotation device 70, so that each position around the top of the measurement object 90 can be set as an end measurement position 95. A number of positions can be consecutively set as end measurement positions 95 around the top of the measurement object 90, or, for example, eight positions at 45 degrees each can be set as end measurement positions 95. The number of end measurement positions 95 to be measured can be appropriately determined taking into consideration the purpose of the measurement, the time required for the measurement, and the like. For example, the number of end measurement positions 95 to be measured can be determined to be a number sufficient to determine whether the trim can is normal or abnormal during the manufacturing process, or whether the process up to the manufacture of the trim can is normal or abnormal.

Measurement by the second measuring device 40 will be described with reference to FIG. 2B. FIG. 2B is a diagram for explaining measurement by the second measuring device 40, and is a plan view that shows a state in which a measurement target 90 is placed on a rotating table 71. The light projector 42 and light receiver 43 of the second measuring device 40 are similar to the light projector 12 and light receiver 13 of the first measuring device 10, respectively.

The light projector 42 and the light receiver 43 are arranged so that the band-shaped laser light 46 is positioned within a horizontal plane. The laser light 16 of the first measuring device 10 and the laser light 46 of the second measuring device 40 are arranged so that they are perpendicular to each other when projected onto the horizontal plane. The light projector 42 and the light receiver 43 of the second measuring device 40 are arranged so that a portion of the band-shaped laser light 46 is blocked by the side of the object to be measured 90.

A portion of the band-shaped laser light 46 irradiated from the projector 42 is blocked by the outer peripheral surface of the measurement object 90. The portion of the laser light 46 on the side of the receiver 13 of the first measuring device 10 of the measurement object 90 passes through and travels to the receiver 43 of the second measuring device 40. The receiver 43 can detect the laser light 46 in the area 47a where all of the laser light 46 irradiated from the projector 42 reaches if there is no measurement object 90. The receiver 43 detects the laser light 46 only in the area 47b where the laser light 46 that is not blocked by the presence of the measurement object 90 reaches. A signal indicating the detection result is transmitted to the computer 80. Based on this signal, the computer 80 identifies the position of the side of the measurement object 90 on the side of the receiver 13 of the first measuring device 10 at the height where the second measuring device 40 is provided. The position of the measurement object 90 on the side of the light receiver 13 of the first measuring device 10 is referred to as the side measurement position 96. In this embodiment, due to the positional relationship described above, the end measurement position 95 and the side measurement position 96 are located on the same plane that includes the axis of the measurement object 90.

[About dimensional measurements]
The dimension measurement according to this embodiment will be further described. In this embodiment, the light projector 12 and the light receiver 13 of the first measuring device 10 are arranged at an angle, so that when the measurement target 90 is distorted, correct measurement cannot be performed. This will be described with reference to FIG.

For example, if the measurement object 90 is a trim can, the thickness of the cylindrical side surface is thin up to the top end, and its rigidity is low. For this reason, the top end of the measurement object 90 is easily deformed to become elliptical. As shown in FIG. 3, even if the height from the top surface of the rotating table 71 to the top end of the measurement object 90 is the same, if the position in the diameter direction of the measurement object 90 is different, the position of the edge of the laser light 16 detected by the receiver 13 will be different. In other words, in contrast to the case where the side wall is ideally vertical as shown by the solid line 90c, if the side wall is deformed outward as shown by the dashed line 90d, the height of the measurement object 90 is measured higher than the actual height based on the detection by the receiver 13. Also, if the side wall is deformed inward as shown by the dotted line 90e, the height of the measurement object 90 is measured lower than the actual height based on the detection by the receiver 13.

In this embodiment, therefore, in order to minimize such measurement errors, the inclination of the first measuring device 10 is set as small as possible. This angle of inclination can be determined, for example, taking into consideration the ellipticity that may occur in the measurement object 90 and the acceptable range of measurement errors. This angle of inclination is, for example, about 0.2 to 2.0°, or about 0.5 to 1.0°. If the angle of inclination of the first measuring device 10 can be made sufficiently small, it may not be necessary to provide the second measuring device 40 described below. Alternatively, by providing the second measuring device 40, the angle of inclination of the first measuring device 10 can be made a little larger.

The measuring device 1 of this embodiment is provided with a second measuring device 40, which measures the position of the side of the measurement object 90 and acquires information related to the deformation of the measurement object 90. The computer 80 uses the value related to this deformation to correct the measurement result by the first measuring device 10 and calculates the height of the measurement object 90. Note that if the ellipticity of the measurement object 90 is extremely high, the measurement object 90 may be excluded from the measurement object. In other words, the need for measurement itself may be determined depending on the ellipticity of the measurement object 90.

A method for deriving the height of the end measurement position 95 of the measurement target 90 will be described with reference to Fig. 4. Using a jig 98 that rises vertically from the rotation table 71 at a known distance from the center of the rotation table 71, the installation angle θ1 of the first measuring device 10 is determined. That is, using a value indicating a height D from the top surface of the rotation table 71 to the tip of the jig 98 outputted from the receiver 13 when the jig 98 is located on the receiver 13 side, a value indicating a height E from the top surface of the rotation table 71 to the tip of the jig 98 outputted from the receiver 13 when the jig 98 is located on the projector 12 side, and a known horizontal distance C between when the jig 98 is located on the receiver 13 side and when it is located on the projector 12 side, the installation angle θ1 is determined as follows:
θ1=tan ^-1 ((DE)/C)
is obtained.

In this embodiment, the height of the measurement object 90 detected by the optical receiver 13 is corrected based on the end measurement position 95 when the measurement object 90 is a perfect circle, that is, based on the case where the side wall is ideally vertical as shown by the solid line 90c in Figure 3.

In the example shown in Fig. 4, the jig 98 is assumed to be in this reference position. For calibration purposes, the measuring device 1 is provided with a calibration member 30 at a known position on the receiver 13 side of the position where the measurement target 90 is placed. The height from the top surface of the rotating table 71 to the top end of the calibration member 30 is defined as height A. The horizontal position of the calibration member 30 is a distance B away from the above-mentioned reference position. Therefore, the edge position value output from the receiver 13 at the above-mentioned reference position is
Height = A + B tan θ1
This corresponds to a value detected as . Using this relationship, a calibration calculation is performed using the value detected by the light receiver 13 when the measurement object 90 is not present on the turntable 71. Therefore, according to the measurement device 1 of this embodiment, it is also possible to perform calibration using the calibration member 30 every time between measurements of the measurement object 90 and the next measurement of the measurement object 90. Calibration using the calibration member 30 does not have to be performed every time the measurement object 90 is measured. By performing calibration frequently as necessary, the measurement device 1 can always perform measurements with high accuracy.

In this embodiment, as described above, the second measuring device 40 is provided, and the side measurement position 96 below the end measurement position 95 is identified. Based on this position, the horizontal deviation of the end measurement position 95 from the reference position can be identified. Using this deviation value, the height from the top surface of the rotating table 71 to the end measurement position 95 can be accurately calculated based on the edge position value output from the optical receiver 13, in the same manner as described above.

In addition, when the measurement object 90 is a perfect circle and the side of the measurement object 90 is vertical, the height of the measurement object 90 measured as described above and the longitudinal length of the side of the measurement object 90 coincide. However, when the measurement object 90 is deformed into an ellipse, the side of the measurement object 90 is inclined. In this case, the height of the measurement object 90 detected as described above and the longitudinal length along the side of the measurement object 90 do not coincide. Since the inclination angle of the side of the measurement object 90 can be obtained based on the side measurement position 96 measured by the second measuring device 40, it is also possible to calculate the longitudinal length of the side of the measurement object 90 based on the height of the measurement object 90.

In this embodiment, the end measurement position 95 and the side measurement position 96 are arranged on the same plane including the axis of the measurement object 90 as described above. However, this is not limited to this. Since the measurement object 90 is measured while rotating around its axis, as long as the positional relationship between the end measurement position 95 and the side measurement position 96 can be grasped, it is possible to handle the situation by data processing even if the end measurement position 95 and the side measurement position 96 are not arranged on the same plane including the axis of the measurement object 90.

Although an example has been shown in which the degree of deformation of the measurement object 90 is obtained from the measurement results of the second measuring device 40 and used for analysis, the measurement results of the second measuring device 40 are not limited to the deformation of the measurement object 90. The measurement object 90 may be placed on the turntable 71 of the rotating device 70 in a state in which the rotation axis of the turntable 71 and the central axis of the measurement object 90 are misaligned, depending on the transportation and holding conditions. According to the measurement results obtained by the second measuring device 40 while rotating the turntable 71, such a misalignment of the axes can also be detected. Based on the measurement results obtained while rotating the turntable 71, it can be determined whether the measurement object 90 is deformed or misaligned. For example, when the amount of change in the measurement results of the second measuring device 40 obtained while rotating the turntable 71 becomes larger than a predetermined value, there is a possibility that a large deformation and/or a large positional shift has occurred, so the measurement by the first measuring device 10 may be invalidated.

[Measuring equipment]
In the measuring device 1 of this embodiment, a transmission type laser measuring instrument is used, so that the height of a cylindrical measurement object 90 having a thin plate thickness can be measured accurately and inexpensively. For example, in a contact type measurement, it is necessary to consider the effect of damaging or deforming the measurement object 90 and the wear of the measuring probe. In contrast, the use of a laser measuring instrument allows measurement to be performed in a non-contact manner, so that measurement can be performed without damaging the measurement object 90. In addition, the use of a transmission type laser measuring instrument allows measurement of the position of the upper end of the measurement object 90, which has an extremely thin plate thickness and has almost no upper surface.

Because the measuring object 90 is not damaged, even if the measuring device 1 is used for sampling inspection in a can manufacturing process, the measuring object 90 after measurement can be returned to the can manufacturing process. In addition, because laser measuring instruments can perform measurements at high speed, by appropriately designing the conveying device 60 and rotating device 70, the measuring device 1 can also be used for 100% inspection in a can manufacturing process, for example.

In addition, there is a known defect in trim cans where the height positions at the start and end of the cut during trimming are misaligned, resulting in a step. By using the measuring device 1, for example, it is possible to precisely measure the height of the top end of the trim can (measurement object 90) at multiple positions around its circumference, thereby inspecting for the occurrence of defects that result in such a step.

In a can manufacturing process, if the measuring device 1 can measure the heights of a large number of measurement objects 90, such as trim cans, the arithmetic device 82 of the computer 80 can analyze the height differences and changes in the heights of the large number of measurement objects 90 based on the measurement results. Based on these height differences and changes, the computer 80 can analyze the state of the material of the measurement objects 90, or the state of the processing device that processed the measurement objects 90. For example, if there is an abnormality in the trimming device, height abnormalities will be detected in a large number of trim cans. In this way, if similar abnormalities are detected continuously, it can be assumed that there is an abnormality in the trimming device or the process preceding it, or that there is an abnormality in the materials. For example, by continuously measuring a large number of trim cans in a can manufacturing process, it is possible to detect signs of abnormalities in the trimming device or other devices.

[Modification]
A modified example will be described below. Differences from the above-described embodiment will be described, and the same parts will be denoted by the same reference numerals and description thereof will be omitted.

First Modified Example
5 is a diagram showing a schematic configuration of a first measuring device 10 according to a first modified example. In this modified example, the measuring device 1 is configured to be able to measure the heights of two types of measurement objects 90 having different heights, i.e., a first measurement object 91 and a second measurement object 92.

For this reason, the measuring device support part 51 that supports the first measuring device 10 is configured to be able to move up and down relative to the support 53 via a movable mechanism 52. With this mechanism, the first measuring device 10 can move parallel up and down between a position suitable for measuring the height of the first measuring object 91 and a position suitable for measuring the height of the second measuring object 92.

The calibration member 30 also has two calibration members, namely a first calibration element 31 and a second calibration element 32, for measuring the height of the first measurement object 91 and the height of the second measurement object 92. The first calibration element 31 and the second calibration element 32 are fixed via a calibration member support part 55 at appropriate positions with different heights. Since the first calibration element 31 and the second calibration element 32 are fixed, even if the height of the first measuring device 10 is changed, appropriate calibration can be easily performed.

The rest of the configuration is the same as in the above-described embodiment. With this configuration, the measuring device 1 can easily measure the heights of two types of measuring objects 90 that are different in height.

Second Modified Example
In the above embodiment, the light projector 12 and the light receiver 13 of the first measuring device 10 are disposed outside the measurement object 90 with the measurement object 90 sandwiched therebetween, but this is not limited thereto. One of the light projector 12 and the light receiver 13 may be disposed inside the measurement object 90 and the other outside the measurement object 90. With this arrangement, only one part of the side wall is located between the light projector 12 and the light receiver 13, instead of two parts of the side wall of the measurement object 90 being located between the light projector 12 and the light receiver 13 as in the above embodiment. Therefore, the first measuring device 10 can be disposed horizontally, that is, parallel to a plane formed including one end of the measurement object 90.

By arranging the light projector 12 and light receiver 13 of the first measuring device 10 close to each other horizontally, the device configuration of this modified example may be superior in terms of arrangement in terms of measurement accuracy compared to the embodiment described above in which the first measuring device 10 is arranged at an angle. However, this modified example requires a mechanism for moving the first measuring device 10 up and down as in the first modified example, and the first measuring device 10 needs to be moved up and down each time a measurement is made. In terms of being able to fix the first measuring device 10, the device configuration of the embodiment described above may be superior in terms of measurement accuracy.

In this modified example in which the first measuring device 10 is positioned horizontally, no error occurs due to the end measurement position 95 being displaced horizontally when the measurement object 90 becomes elliptical, for example. However, it is useful to make corrections in the calculation of the length of the side of the measurement object 90 by measuring the side measurement position 96, for example, to measure the inclination of the side of the measurement object 90.

<Third Modification>
In the above embodiment, a transmission type laser measuring instrument similar to the first measuring instrument 10 is used as the second measuring instrument 40. However, this is not limited to this. A relatively wide surface exists at the side measurement position 96 measured by the second measuring instrument 40. Therefore, instead of the second measuring instrument 40 which is a transmission type laser measuring instrument, various measuring instruments such as a reflection type laser displacement sensor, an eddy current type displacement sensor, an ultrasonic type displacement sensor, etc. may be used.

The present invention has been described above with reference to preferred embodiments, but it goes without saying that the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the present invention.

1: Measuring device 10: First measuring device, 12: Light projector, 13: Light receiver, 16: Laser light 30: Calibration member, 31: First calibration element, 32: Second calibration element 40: Second measuring device, 42: Light projector, 43: Light receiver, 46: Laser light 51: Measuring device support, 52: Movable mechanism, 53: Support, 55: Calibration member support 60: Transport device, 61: First transport device, 62: Second transport device, 621: Transport table, 622: Transport arm, 623: Motor, 63: Third transport device 70: Rotation device, 71: Rotation table, 72: Motor 80: Computer, 81: Control device, 82: Arithmetic device 90: Measurement object, 91: First measurement object, 92: Second measurement object, 95: End measurement position, 96: Side measurement position, 98: Jig

Claims (16)

a first measuring device including a transmission type laser measuring device configured to have a light projector and a light receiver disposed on either side of an end measurement position, the end measurement position being a position of a portion of the circumference of one end of a cylindrical measurement object, and configured to output a first signal indicative of the end measurement position;
and a calculation device configured to calculate a length from a reference position of the object to be measured to the end measurement position based on the first signal. The measuring device according to claim 1, wherein the light projector is configured to irradiate the laser light in a band-like parallel manner at an angle with respect to a surface formed including the one end of the object to be measured. The measurement device according to claim 2, wherein the light projector and the light receiver are disposed outside the object to be measured, sandwiching the entire object to be measured. a calibration member disposed at a known position;
The known position of the calibration member may be
When the measurement target is not present at a measurable position where the first measuring device can identify the end measurement position, a part of the laser light irradiated from the light projector is blocked,
a position where the laser light irradiated from the light projector does not hit because the laser light is blocked by the object to be measured when the object to be measured is present at the measurable position;
the first measuring device outputs a second signal indicating a position of an end of the calibration member at least once when the measurement object is not present at the measurable position;
The calculation device is configured to perform a calibration calculation based on the second signal when calculating the length.
4. A measuring device according to claim 1. the calibration member includes a plurality of calibration elements fixed at different known positions corresponding to a plurality of types of the measurement objects,
The light projector and the light receiver are configured to be movable to different positions according to a plurality of types of the measurement objects.
5. The measuring device according to claim 4. a second measuring device configured to measure a side surface measurement position that is a part of a side surface of the measurement object and output a third signal indicating the side surface measurement position;
The arithmetic unit is configured to perform a calibration calculation using the third signal when calculating the length, or to determine whether or not it is necessary to calculate the length based on the third signal.
4. A measuring device according to claim 1. The measuring device according to claim 6, wherein the end measurement position and the side measurement position are located in the same plane including the axis of the measurement object. The measurement device according to claim 6, wherein the second measuring device includes a transmission type laser measuring device configured such that a light projector and a light receiver are disposed outside the measurement object with the side measurement position in between. The light projector is configured to irradiate a band of laser light parallel to a surface formed including the one end of the object to be measured,
One of the light projector and the light receiver is arranged inside the measurement object, and the other of the light projector and the light receiver is arranged outside the measurement object.
2. The measuring device of claim 1. a rotation device configured to rotate the measurement object around an axis of the measurement object,
the first measuring device is configured to identify a plurality of edge measurement positions in one of the measurement objects;
The arithmetic device is configured to calculate lengths from a plurality of the reference positions to the end measurement positions in one of the measurement objects.
4. A measuring device according to claim 1. The measuring device according to claim 10, wherein the computing device is configured to determine whether or not there is a step around one end of the object to be measured. a conveying device configured to sequentially convey the plurality of measurement objects to a measurement position where the first measuring device can identify the end measurement position;
the first measuring device is configured to sequentially identify the end measurement positions of the plurality of measurement objects;
The computing device is configured to calculate the lengths of the plurality of measurement objects and analyze the differences in the lengths of the plurality of measurement objects.
4. A measuring device according to claim 1. The measuring device according to claim 12, wherein the computing device is configured to analyze the state of the material of the measured object or the state of the processing device that processed the measured object based on the difference in length. The measuring device according to any one of claims 1 to 3, wherein the object to be measured is a can that has been trimmed after drawing and ironing in a can manufacturing process. A cylindrical object is disposed between a light projector and a light receiver of a transmission type laser measurement instrument such that an end measurement position, which is a part of a circumference of one end of the object, is located;
measuring the edge measurement position with the laser measuring device;
acquiring a first signal indicating a measurement result of the end measurement position, and calculating a length from a reference position of the object to be measured to the end measurement position based on the first signal. A method for manufacturing a can, comprising the measurement method according to claim 15.

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