JP2020003225A - Rubber sheet length measuring device and rubber sheet length measuring method - Google Patents

Abstract

To provide a length measuring device 2 capable of measuring the length of a rubber sheet 4 more accurately.SOLUTION: The length measuring device 2 for the rubber sheet 4 includes: an encoder 22 for outputting a pulse signal associated with a conveyance speed of the rubber sheet 4; photographing means 24 set toward the rubber sheet 4 for photographing at a plurality of times the rubber sheet 4 moving on a conveyor 6 in synchronization with the encoder 22; and measuring means 26b for measuring the length of the rubber sheet 4 on the basis of the pulse signal and an entire image of the rubber sheet 4 obtained by the photographing means 24. The photographing means 24 is a line camera.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rubber sheet length measuring device and a rubber sheet length measuring method. More specifically, the present invention relates to a rubber sheet length measuring device used for manufacturing a tire and a rubber sheet length measuring method.

  In the manufacture of a tire, for example, a tread is formed by winding a rubber sheet for the tread on a drum and joining both end surfaces. This rubber sheet is obtained by extruding the rubber composition into a belt shape, and cutting the belt-shaped rubber composition to a predetermined length using a cutting tool.

  The tread includes a joint portion of the rubber sheet. The joints affect the uniformity of the tire. In the manufacture of tires, the length of the rubber sheet is controlled so that the rubber sheet is not too short or too long.

  In managing the length of the rubber sheet, it is required to accurately measure the length of the rubber sheet. Various studies have been made on a measuring device and a measuring method of the length of the rubber sheet (for example, Patent Document 1 below).

  In the measuring device disclosed in Patent Literature 1, two photographing units are used. One end of the rubber sheet is photographed by one photographing unit from above the rubber sheet, and the other end is photographed by the other photographing unit. The length of the rubber sheet is measured based on the images of both ends obtained by photographing.

JP 2009-115715 A

  In a conventional measuring device, an area camera in which light receiving elements are arranged two-dimensionally is used as a photographing unit. A rubber sheet for a tread, for example, as a component of a tire is long. When a rubber sheet is divided into a plurality of pieces and photographed for measuring the length of the rubber sheet, and the obtained images are combined to obtain an entire image, the entire image has a large number of pixels. Arithmetic processing of an image having a large number of pixels is not easy.

  In the measurement of the length of a long rubber sheet, it is common to use two photographing means as in the measuring device disclosed in Patent Document 1 described above.

  As described above, in Patent Literature 1, the length of the rubber sheet is measured based on images at both ends obtained by photographing. The images at both ends used for this measurement are taken in the process of placing and transporting the rubber sheet on the conveyor. In the conveyance of the rubber sheet, the direction of the rubber sheet being conveyed may be disturbed. There is a risk that this disturbance cannot be grasped only from the images at both ends. This disturbance affects the accuracy of the rubber sheet length measurement.

  The demand for tire uniformity is high, and there is a need to establish a technology that can more accurately measure the length of a rubber sheet.

  The present invention has been made in view of such circumstances, and provides a rubber sheet length measuring device and a rubber sheet length measuring method capable of more accurately measuring the length of a rubber sheet. The purpose is.

The rubber sheet length measuring device according to the present invention, in the process of placing a rubber sheet obtained by cutting a belt-shaped rubber molded article on a conveyor and transporting the rubber sheet at a predetermined transport speed, Is a device for measuring This measuring device
An encoder that outputs a pulse signal associated with the transport speed,
A photographing unit that is set toward the rubber sheet, and photographs the rubber sheet moving the conveyor in synchronization with the encoder in a plurality of times,
Measuring means for measuring the length of the rubber sheet based on the pulse signal and the entire image of the rubber sheet obtained by the photographing means, wherein the photographing means is a line camera.

  Preferably, in the rubber sheet length measuring device, the measuring unit acquires a moving distance of the rubber sheet based on the pulse signal and the transport speed, and displays the moving distance as an entire image of the rubber sheet. The position coordinates of each part of the rubber sheet in the entire image of the rubber sheet are specified in association with the above.

Preferably, the rubber sheet length measuring device includes a first sensor and a second sensor which are set toward the rubber sheet and detect passage of the rubber sheet. The photographing means is located between the first sensor and the second sensor,
When the first sensor detects the passage of the front end of the rubber sheet, the photographing unit starts photographing, and when the second sensor detects the passage of the rear end of the rubber sheet, the photographing unit starts photographing. finish.

  Preferably, the rubber sheet length measuring device includes a main light arranged to face the photographing means with the rubber sheet interposed therebetween. The main camera emits light toward the photographing unit.

  Preferably, in the rubber sheet length measuring device, both end surfaces of the rubber sheet are inclined surfaces inclined with respect to the length direction of the rubber sheet, and a sub-surface is provided to illuminate the end surface facing the photographing means. A light is provided.

  Preferably, in this rubber sheet length measuring device, an end surface at a rear end of the rubber sheet faces the photographing unit.

The method for measuring the length of a rubber sheet according to the present invention is characterized in that, in the process of placing a rubber sheet obtained by cutting a belt-shaped rubber molded article on a conveyor and transporting the rubber sheet at a predetermined transport speed, Is a method for measuring. This measurement method is
(1) Using a photographing unit set toward the rubber sheet, synchronizing the photographing unit with an encoder that outputs a pulse signal related to the transport speed, and moving the rubber sheet moving the conveyor a plurality of times. (2) measuring the length of the rubber sheet based on the pulse signal and the entire image of the rubber sheet obtained by the photographing unit; The means is a line camera.

  In the rubber sheet length measuring device according to the present invention, the photographing means is synchronized with an encoder that outputs a pulse signal associated with the transport speed, and the entire rubber sheet is photographed in a plurality of times, so that the rubber sheet can be photographed. An entire image is obtained. Since the line camera is used as the photographing means, the number of pixels of the whole image is small as compared with the case where the area camera is used as the photographing means, and the calculation processing of this whole image is easy. Since the length of the rubber sheet is measured based on the entire image, it is possible to measure the length in consideration of, for example, disturbance in the direction of the rubber sheet in conveyance. This measuring device can more accurately measure the length of the rubber sheet. Moreover, since only one photographing means is required, this measuring device can contribute to downsizing.

  Also in the rubber sheet length measuring method according to the present invention, by synchronizing the photographing means with an encoder that outputs a pulse signal associated with the transport speed, by photographing the entire rubber sheet in a plurality of times, Is obtained. Since the line camera is used as the photographing means, the number of pixels of the whole image is small as compared with the case where the area camera is used as the photographing means, and the calculation processing of this whole image is easy. Since the length of the rubber sheet is measured based on the entire image, it is possible to measure the length in consideration of, for example, disturbance in the direction of the rubber sheet in conveyance. This measuring method can more accurately measure the length of the rubber sheet. Moreover, since only one photographing means is required, this measuring method can contribute to downsizing of the measuring device.

  According to the present invention, a rubber sheet length measuring device and a rubber sheet length measuring method capable of measuring the length of a rubber sheet more accurately can be obtained.

FIG. 1 is a diagram showing an outline of a rubber sheet length measuring device according to an embodiment of the present invention. FIG. 2 is a diagram for explaining a photographing situation of the tip of the rubber sheet. FIG. 3 is a diagram for explaining a shooting state of the rear end of the rubber sheet. FIG. 4 is a diagram showing an entire image of the rubber sheet.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with reference to the drawings as appropriate.

  FIG. 1 shows an outline of a measuring device 2 according to an embodiment of the present invention. The measuring device 2 is a device for measuring the length of the rubber sheet 4 in the process of placing the rubber sheet 4 on the conveyor 6 and transporting the rubber sheet 4 at a predetermined transport speed.

  In FIG. 1, the left-right direction is the transport direction of the rubber sheet 4. In the measuring device 2, the rubber sheet 4 is conveyed from the right side to the left side. 1, the right side of the drawing is the upstream side of the measuring device 2 and the left side of the drawing is the downstream side of the measuring device 2 in FIG.

[Rubber sheet 4]
The rubber sheet 4 whose length is measured by the measuring device 2 is formed by cutting an unvulcanized rubber composition through an extruder (not shown) into a band-shaped rubber composition, and cutting the rubber composition into a cutting device (not shown). )).

  In the measuring device 2, the rubber sheet 4 to be measured is not particularly limited. Examples of the rubber sheet 4 include a rubber sheet for a tread, a rubber sheet for a sidewall, a rubber sheet for an apex, and the like as tire components.

  In FIG. 1, reference numeral UF is a front end of the upper surface 8 of the rubber sheet 4. The symbol UE is the rear end of the upper surface 8. Reference sign SF is the front end of the lower surface 10 of the rubber sheet 4. The symbol SE is the rear end of the lower surface 10. In the measuring device 2, the length of the upper surface 8 of the rubber sheet 4, that is, the length from the front end UF to the rear end UE, indicated by the double-headed arrow L, is measured as the length of the rubber sheet 4.

  In the rubber sheet 4, a portion including the front end UF of the upper surface 8 and the front end SF of the lower surface 10 is referred to as a front end portion 12, and a portion including the rear end UE of the upper surface 8 and the rear end SE of the lower surface 10 is a rear end. It is referred to as a unit 14. A surface bridging the front end UF of the upper surface 8 and the front end SF of the lower surface 10 and a surface bridging the rear end UE of the upper surface 8 and the rear end SE of the lower surface 10 are end surfaces 16 obtained by cutting.

[Measurement device 2]
The measuring device 2 is provided in the course of transporting the completed rubber sheet 4 on a production line of the rubber sheet 4 to a storage device (not shown) by the conveyor 6. The measuring device 2 is also a part of a production line for the rubber sheet 4. The measuring device 2 may be provided independently of the production line.

  In this measuring device 2, the conveyor 6 includes a number of rollers 18 arranged in parallel in the transport direction. Although not shown, the conveyor 6 includes a frame extending in the transport direction, and the frame rotatably supports the roller 18. This conveyor 6 is a roller conveyor.

  Examples of the roller conveyor include a free roller conveyor in which the roller 18 is not driven and a driving roller conveyor in which the roller 18 is driven.

  In the measuring device 2 shown in FIG. 1, the conveyor 6 is a drive roller conveyor. In this conveyor 6, the rollers 18 are rotated by driving means (not shown). The driving means includes a chain, a belt, a motor, and the like. In the measuring device 2, a free roller conveyor may be used as the roller conveyor. As the conveyor 6, a belt conveyor may be used.

  As described above, in the measuring device 2, the rubber sheet 4 obtained by cutting the belt-shaped rubber molded product is conveyed by the conveyor 6. As shown in FIG. 1, in the measuring device 2, the rubber sheet 4 is placed on the conveyor 6 such that the end surface 16 of the rubber sheet 4 formed by cutting faces in the transport direction.

  In the conveyor 6 of the measuring device 2, the mounting surface 20 on which the rubber sheet 4 is mounted expands horizontally. In the measuring device 2, the rubber sheet 4 is placed horizontally on the conveyor 6.

  The measuring device 2 includes an encoder 22, a photographing unit 24, and a control device 26, in addition to the conveyor 6 that conveys the rubber sheet 4.

  The encoder 22 outputs the displacement of rotation as a pulse signal. This encoder 22 is also called a rotary encoder. In the measuring device 2, the encoder 22 is attached to a rotating shaft (not shown) of the roller 18 of the conveyor 6, and outputs a displacement of the rotation of the roller 18 as a pulse signal.

  As shown in FIG. 1, in the measuring device 2, the rubber sheet 4 comes into contact with the roller 18. The rubber sheet 4 is conveyed downstream by the rotation of the roller 18. In the measuring device 2, for example, the transport speed of the rubber sheet 4 is obtained based on the outer diameter (or circumference) of the roller 18 and the pulse signal output from the encoder 22. This encoder 22 outputs a pulse signal related to the transport speed of the rubber sheet 4.

  In the measuring device 2, there is no particular limitation on the position of the encoder 22 in the measuring device 2 as long as a pulse signal associated with the transport speed of the rubber sheet 4 passing through the photographing position of the photographing unit 24 described later can be obtained. . In the measuring device 2 shown in FIG. 1, the encoder 22 is attached to the roller 18 located on the upstream side of the photographing means 24.

  The photographing means 24 is set to face the rubber sheet 4 placed on the conveyor 6. As shown in FIG. 1, the photographing means 24 of the measuring device 2 is set from above the rubber sheet 4 toward the rubber sheet 4.

  In the measuring device 2, the photographing means 24 is a line camera. This line camera includes light receiving elements arranged in a straight line, not two-dimensionally as in an area camera. In the measuring device 2, the photographing unit 24 photographs an image along the width direction of the conveyor 6. As the line camera, for example, a product name “Line Scan Camera: XG-HL02M” manufactured by Keyence Corporation can be mentioned.

  As described above, the encoder 22 outputs a pulse signal associated with the transport speed of the rubber sheet 4. In the measuring device 2, the photographing unit 24 photographs the rubber sheet 4 moving on the conveyor 6 in a plurality of times in synchronization with the encoder 22. Thereby, an entire image of the rubber sheet 4 is obtained.

  The control device 26 is configured by a microcomputer having a calculation unit such as a CPU, a storage unit including a RAM and a ROM, and the like, and performs a predetermined function when the calculation unit executes a program stored in the storage unit.

  The control device 26 has, as one component of the measuring device 2, a function as a synchronizing unit 26 a that causes the photographing unit 24 to photograph the rubber sheet 4 by inputting a pulse signal from the encoder 22. The synchronizing means 26a synchronizes the photographing means 24 with the encoder 22, and causes the photographing means 24 to photograph the entire rubber sheet 4 a plurality of times at predetermined time intervals.

  The control device 26 serves as a component of the measuring device 2 as a measuring device 26 b that measures the length L of the rubber sheet 4 based on the input of a pulse signal from the encoder 22 and the input of an image signal from the photographing device 24. Has functions. The measuring unit 26b measures the length L of the rubber sheet 4 based on the pulse signal and the entire image of the rubber sheet 4 obtained by the photographing unit 24. More specifically, the measuring unit 26b acquires the moving distance of the rubber sheet 4 based on the pulse signal and the transport speed, and associates the moving distance with the entire image of the rubber sheet 4 so that the entire rubber sheet 4 can be moved. The position coordinates of each part of the rubber sheet 4 in the image are specified. Then, in the entire image of the rubber sheet 4, the ends in the length direction, that is, the positions of the front end UF and the rear end UE of the upper surface 8 are obtained, and the length L of the rubber sheet 4 is measured based on the positions of these ends. Is done.

  In this measuring device 2, the entire image of the rubber sheet 4 is taken by synchronizing the photographing means 24 with the encoder 22 that outputs a pulse signal associated with the transport speed and photographing the entire rubber sheet 4 in a plurality of times. Is obtained. Since a line camera is used as the image capturing means 24, the number of pixels of the entire image is smaller than when an area camera is used as the image capturing means, and the arithmetic processing of the entire image is easy. Since the length L of the rubber sheet 4 is measured based on the entire image, it is possible to measure the length L in consideration of, for example, disturbance in the direction of the rubber sheet 4 during conveyance. This measuring device 2 can measure the length L of the rubber sheet 4 more accurately. Moreover, since only one photographing means 24 is required, this measuring device 2 can contribute to downsizing.

  This measuring device 2 includes a first sensor 28 and a second sensor 30. As shown in FIG. 1, the first sensor 28 and the second sensor 30 are set toward the rubber sheet 4 above the rubber sheet 4. In the measuring device 2, the photographing unit 24 is located between the first sensor 28 and the second sensor 30.

  The first sensor 28 is located on the upstream side of the photographing unit 24. As shown in FIG. 2, the rubber sheet 4 passes through the first sensor 28 and then passes through the photographing unit 24. In the measuring device 2, the first sensor 28 is a photoelectric sensor. The first sensor 28 outputs a first detection signal when detecting that the front end 12 of the rubber sheet 4 has passed. This first detection signal is input to the control device 26 described above.

  In the measuring device 2, the control device 26 has a function as a start unit 26 c that causes the photographing unit 24 to start photographing in response to the input of the first detection signal from the first sensor 28. When the first sensor 28 detects that the front end portion 12 of the rubber sheet 4 has passed, the start unit 26c causes the photographing unit 24 to start photographing.

  The second sensor 30 is located downstream of the photographing unit 24. As shown in FIG. 3, the rubber sheet 4 passes through the second sensor 30 after passing through the photographing means 24. In the measuring device 2, the second sensor 30 is a photoelectric sensor. The second sensor 30 outputs a second detection signal when detecting the passage of the rear end portion 14 of the rubber sheet 4. This second detection signal is input to the control device 26 described above.

  In the measuring device 2, the control device 26 has a function as an ending unit 26 d that causes the imaging unit 24 to end the imaging in response to the input of the second detection signal from the second sensor 30. When the second sensor 30 detects the passage of the rear end portion 14 of the rubber sheet 4, the ending means 26d causes the photographing means 24 to terminate the photographing.

  In this measuring device 2, the conveyor 6 is moved after the position of the front end 12 of the rubber sheet 4 is grasped by the first sensor 28 and the position of the rear end 14 of the rubber sheet 4 is grasped by the second sensor 30. The rubber sheet 4 is photographed by the photographing means 24. In the measuring device 2, the rubber sheet 4 is reliably photographed by the photographing means 24, and image data relating to the rubber sheet 4 can be easily specified. Providing the first sensor 28 and the second sensor 30 in the measuring device 2 contributes to reliably and efficiently measuring the length L of the rubber sheet 4. From this viewpoint, it is preferable that the measuring device 2 includes a first sensor 28 and a second sensor 30 which are set toward the rubber sheet 4 and detect the passage of the rubber sheet 4. In this case, the photographing unit 24 is located between the first sensor 28 and the second sensor 30, and when the first sensor 28 detects the passage of the front end 12 of the rubber sheet 4, the photographing unit 24 starts photographing, The measuring device 2 is preferably configured so that the photographing means 24 terminates photographing when the two sensors 30 detect the passage of the rear end portion 14 of the rubber sheet 4.

  As described above, in the measurement device 2, when the first sensor 28 detects the passage of the front end portion 12 of the rubber sheet 4, the photographing unit 24 starts photographing. In this measuring device 2, the photographing is performed in synchronization with the encoder 22. Therefore, when the first sensor 28 is provided on the upstream side of the photographing means 24, the encoder 22 is positioned upstream of the first sensor 28. More preferably, the roller 18 is provided on the roller 18. From the viewpoint of accurately grasping the transport speed of the rubber sheet 4 passing through the photographing position of the photographing means 24, the encoder 22 is preferably provided at a position close to the photographing means 24. In the case where the encoder 28 is provided, the encoder 22 is preferably provided on the roller 18 located at a position upstream of the first sensor 28 and close to the first sensor 28.

  The rubber sheet 4 has a pair of side edges 32 extending in the length direction. In the rubber sheet 4 being conveyed, grasping the direction of the side edge 32 contributes to detection of a disturbance in the direction of the rubber sheet 4 during conveyance.

  This measuring device 2 includes a main light 34. As shown in FIG. 1, the main light 34 is arranged to face the photographing unit 24 with the rubber sheet 4 interposed therebetween. The main camera irradiates light from below the rubber sheet 4 to the photographing means 24.

  As described above, in the measuring device 2, a line camera is used as the photographing unit 24. For this reason, even if light is emitted from the main light 34 toward the photographing means 24, the influence of the light on the image quality is smaller than when the area camera is used as the photographing means 24. In the measuring device 2, since the rubber sheet 4 blocks the light of the main light 34, the whole image of the rubber sheet 4 in which the side edges 32 of the rubber sheet 4 are clearly shown can be obtained.

  In the measuring device 2, the side edge 32 of the rubber sheet 4 is clearly shown in the image of the rubber sheet 4 obtained by photographing. The length L is measured. In the measuring device 2, the length L of the rubber sheet 4 is measured more accurately. From this viewpoint, the measuring device 2 includes a main light 34 that is disposed to face the photographing unit 24 with the rubber sheet 4 interposed therebetween, and the main camera irradiates the photographing unit 24 with light. Preferably. In this case, from the viewpoint of effectively irradiating the rubber sheet 4 with light and obtaining an image in which the side edges 32 are clearly shown, the photographing unit 24 and the main light 34 are, as shown in FIG. More preferably, it is arranged between one roller 18 and another roller 18 located next to the one roller 18.

  In the measuring device 2, the main light 34 is not particularly limited as long as an image in which the side edge 32 of the rubber sheet 4 is clearly shown can be obtained. The main light 34 includes, for example, a bar-shaped LED illumination.

  As described above, the rubber sheet 4 is obtained by cutting a band-shaped rubber composition with a cutting device. In the manufacture of a tire, a cutting tool of a cutting device is obliquely inserted into a band-shaped rubber composition in order to use a cut surface as a joint surface. For this reason, the cut surface of the rubber sheet 4, that is, the end surface 16 is inclined with respect to the length direction. Both end surfaces 16 of the rubber sheet 4 are inclined surfaces inclined with respect to the length direction of the rubber sheet 4.

  In the measuring device 2, from the viewpoint of smooth conveyance of the rubber sheet 4, the end surface 16 of the front end portion 12 faces the conveyor 6 and the end surface 16 of the rear end portion 14 faces the photographing unit 24. Is placed on the conveyor 6.

  In this measuring device 2, the rubber sheet 4 is photographed from above, so that the image of the front end portion 12 of the rubber sheet 4 does not include the end face 16. As described above, in the measuring device 2, the main light 34 illuminates the rubber sheet 4 from below. Therefore, in the image of the front end portion 12, the end UF of the upper surface 8 of the rubber sheet 4 is clearly shown as shown in FIG.

  On the other hand, the image of the rear end portion 14 of the rubber sheet 4 includes the end face 16. Clearly representing the rear end UE of the upper surface 8, that is, the boundary between the upper surface 8 and the end surface 16 in the image of the rear end portion 14 contributes to more accurate measurement of the length L of the rubber sheet 4.

  The measuring device 2 includes a sub light 36. As shown in FIG. 3, the sub light 36 is arranged on the upstream side of the photographing unit 24 so as to illuminate the end surface 16 of the rear end portion 14 of the rubber sheet 4 passing through the photographing position of the photographing unit 24.

  As described above, in the measuring device 2, a line camera is used as the photographing unit 24. For this reason, light is emitted from the sub light 36 toward the end face 16, and a portion (for example, a roller 18 located near the shooting position and downstream of the shooting position near the shooting position and reflecting light other than the end face 16 (that is, the background)). ), The reflection of light does not affect the image quality as in the case of shooting with an area camera.

  As shown in FIG. 4, in the measurement device 2, an image in which the boundary between the upper surface 8 and the end surface 16, that is, the rear end UE of the upper surface 8 is clearly displayed is obtained. In the measuring device 2, the length L of the rubber sheet 4 is measured more accurately. From this point of view, when the both end surfaces 16 of the rubber sheet 4 are inclined surfaces with respect to the length direction of the rubber sheet 4, the measuring device 2 Preferably, a light 36 is provided. From the viewpoint that the length L of the rubber sheet 4 is more accurately measured while smoothly transporting the rubber sheet 4, the end surface 16 of the rear end portion 14 of the rubber sheet 4 faces the photographing unit 24. The rubber sheet 4 is preferably placed on a conveyor 6.

  In the measuring device 2, the sub light 36 is not particularly limited as long as an image in which the boundary between the upper surface 8 and the end surface 16 of the rubber sheet 4, that is, the rear end UE of the upper surface 8 is clearly obtained. . Examples of the sub light 36 include a bar-shaped LED illumination.

[Measuring method]
Next, a measuring method according to another embodiment of the present invention will be described. In this measuring method, the measuring device 2 shown in FIG. 1 is used. This measuring method is used to measure the length of the rubber sheet 4 in the process of placing the rubber sheet 4 obtained by cutting the belt-shaped rubber molded article on the conveyor 6 and transporting the rubber sheet 4 at a predetermined transport speed. Is the way. This measuring method includes a photographing step and a measuring step.

  In the photographing step, the photographing means 24 set toward the rubber sheet 4 is used to synchronize the photographing means 24 with the encoder 22 which outputs a pulse signal associated with the transport speed, and the rubber sheet moving the conveyor 6 is used. 4 is photographed in a plurality of times.

  In the measurement step, the length L of the rubber sheet 4 is measured based on the pulse signal and the entire image of the rubber sheet 4 obtained by the photographing unit 24.

  In this measurement method as well, the entire image of the rubber sheet 4 is obtained by synchronizing the photographing unit 24 with the encoder 22 that outputs a pulse signal associated with the transport speed and photographing the entire rubber sheet 4 in a plurality of times. can get. Since a line camera is used as the image capturing means 24, the number of pixels of the entire image is smaller than when an area camera is used as the image capturing means, and the arithmetic processing of the entire image is easy. Since the length of the rubber sheet 4 is measured based on the entire image, it is possible to measure the length in consideration of, for example, disturbance in the direction of the rubber sheet 4 during conveyance. This measuring method can measure the length of the rubber sheet 4 more accurately. Moreover, since only one photographing means 24 is required, this measuring method can contribute to downsizing of the measuring device 2.

  In this measuring method, from the viewpoint of reliably and efficiently measuring the length L of the rubber sheet 4, in the photographing step, the first sensor 28 is provided on the upstream side of the photographing means 24, and the first sensor 28 is provided. When the passage of the front end 12 of the rubber sheet 4 is detected, the photographing means 24 starts photographing, and a second sensor 30 is provided downstream of the photographing means 24, and the second sensor 30 is provided at the rear end of the rubber sheet 4. It is preferable that the photographing means 24 terminates the photographing when the passage of 14 is detected.

  In this measuring method, further, from the viewpoint of more accurately measuring the length L of the rubber sheet 4, in the photographing step, a main light 34 is provided opposite to the photographing means 24 with the rubber sheet 4 interposed therebetween. It is preferable that the main light 34 emits light toward the photographing means 24.

  In this measuring method, from the viewpoint that the length L of the rubber sheet 4 is more accurately measured, a sublight 36 that illuminates the end surface 16 of the rubber sheet 4 facing the photographing means 24 is provided in the photographing step. preferable. In this case, from the viewpoint that the length L of the rubber sheet 4 is more accurately measured while smoothly transporting the rubber sheet 4, the end surface 16 of the rear end portion 14 of the rubber sheet 4 faces the photographing unit 24. Preferably, the rubber sheet 4 is placed on a conveyor 6.

  As is apparent from the above description, according to the present invention, the rubber sheet 4 length measuring device 2 and the rubber sheet 4 length measuring method capable of measuring the length of the rubber sheet 4 more accurately can be obtained. .

  The embodiment disclosed this time is an example in all respects and is not restrictive. The technical scope of the present invention is not limited to the above-described embodiment, and includes all modifications within a scope equivalent to the configuration described in the claims.

  The technology for measuring the length of a rubber sheet described above can also be applied to various length measurements of a rubber sheet.

2 ... Measuring device 4 ... Rubber sheet 6 ... Conveyor 8 ... Upper surface of rubber sheet 4 10 ... Lower surface of rubber sheet 4 12 ... Front end of rubber sheet 4 14 ... Rubber Rear end portion of sheet 4 16 End surface of rubber sheet 4 18 Roller 20 Placing surface of conveyor 6 22 Encoder 24 Photographing means 26 Control device 26a Synchronizing means 26b Measuring means 26c Starting means 26d Ending means 28 First sensor 30 Second sensor 32 Side edge of rubber sheet 4 34 Main Light 36 ... Sub light

Claims (7)

In the process of placing a rubber sheet obtained by cutting a belt-shaped rubber molded article on a conveyor and transporting the rubber sheet at a predetermined transport speed, an apparatus for measuring the length of the rubber sheet,
An encoder that outputs a pulse signal associated with the transport speed,
A photographing unit that is set toward the rubber sheet, and photographs the rubber sheet moving the conveyor in synchronization with the encoder in a plurality of times,
Measuring means for measuring the length of the rubber sheet based on the pulse signal and the entire image of the rubber sheet obtained by the photographing means,
A length measuring device for a rubber sheet, wherein the photographing means is a line camera.   In the measuring means, the moving distance of the rubber sheet is acquired based on the pulse signal and the transport speed, and the moving distance is associated with the entire image of the rubber sheet, so that the rubber sheet in the entire image of the rubber sheet is obtained. 2. The rubber sheet length measuring device according to claim 1, wherein the position coordinates of each part are specified. A first sensor and a second sensor that are set toward the rubber sheet and detect passage of the rubber sheet,
The photographing means is located between the first sensor and the second sensor,
When the first sensor detects the passage of the front end of the rubber sheet, the photographing unit starts photographing, and when the second sensor detects the passage of the rear end of the rubber sheet, the photographing unit starts photographing. The rubber sheet length measuring device according to claim 1, wherein the measurement is terminated. A main light disposed opposite to the photographing unit with the rubber sheet interposed therebetween;
The rubber sheet length measuring device according to any one of claims 1 to 3, wherein the main camera irradiates light toward the photographing unit. Both end surfaces of the rubber sheet are inclined surfaces inclined with respect to the length direction of the rubber sheet,
The rubber sheet length measuring device according to any one of claims 1 to 4, wherein a sublight is provided to illuminate an end surface facing the photographing unit.   The rubber sheet length measuring device according to claim 5, wherein an end surface at a rear end portion of the rubber sheet faces the photographing unit. In the process of placing the rubber sheet obtained by cutting the belt-shaped rubber molded article on a conveyor and transporting the rubber sheet at a predetermined transport speed, a method for measuring the length of the rubber sheet,
Using a photographing unit set toward the rubber sheet, synchronizing the photographing unit with an encoder that outputs a pulse signal associated with the transport speed, dividing the rubber sheet moving the conveyor into a plurality of times The process of shooting,
Based on the pulse signal and the entire image of the rubber sheet obtained by the imaging unit, including a measurement step of measuring the length of the rubber sheet,
A method for measuring the length of a rubber sheet, wherein the photographing means is a line camera.