JPH01197609A - Overlap quantity measuring instrument for joint part of beltlike member - Google Patents

Abstract

PURPOSE:To speedily measure the overlap quantity of the joint part with high accuracy by winding the beltlike member around a drum and the detecting the front end before the front end is covered with the beltlike member. CONSTITUTION:While the forming drum 12 is rotated by a motor 13 as shown by an arrow A, a rubber sheet 11 is wound around the drum 12. When the front end of the rubber sheet 11 reaches the detection position of an edge detector 16, the detector 16 detects that and outputs a front end signal. Then the rubber sheet 1 is superposed partially on the drum 12 and wound. The overlap quantity of the superposed joint part is the length between the front end 11A and rear end 11B. Then the drum 12 is reversed and the detector 16 detects the rear end 11B of the rubber sheet 11 and generates a rear end signal. Then the counter of an arithmetic circuit 15 counts output pulses from a rotary encoder 14 reversibly from the detection of the font end 11A to the detection of the rear end 11B to find the quantity of rotation from the front end 11A to the rear end 11B, i.e. the overlap quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a device for measuring the amount of overlap at the joint portion of a band member wound partially overlappingly on the circumferential surface of a drum while rotating the drum. It is.

(Prior Art) For example, in the manufacturing process of pneumatic tires, there is a step of wrapping a pre-vulcanized rubber sheet around a forming drum so as to partially overlap it. Fig. 5A shows a state in which the rubber sheet 2 is partially overlapped and wound around the rotating molding drum l, and Fig. 5B shows an enlarged view of the overlapping part, that is, the joint part. be. In such a winding operation, it is necessary to check whether the overlap amount W at the joint portion is within a specified value.

In other words, if the overlap amount W at the joint part is outside the specified range, the manufactured tire may not have the desired performance.
need to be measured.

Conventionally, there is a method for measuring the amount of overlap W at the joint of a rubber sheet wound on a forming drum by having a worker visually measure it, but it has the drawback that the measurement results cannot be standardized and requires skill. However, there were drawbacks such as the possibility of human error being introduced. For this reason, technology is being developed to automatically measure the amount of overlap at the joint. Conventional automatic measurement methods focus on the fact that the outer surface of the joint protrudes, and detect this unevenness using a contact or non-contact method, or capture an image of the joint using a television camera and perform image processing. Methods for calculating the amount of overlap have been proposed.

(Problems to be Solved by the Invention) Among the conventional overlap measurement methods described above, those that detect irregularities have a drawback of poor accuracy. That is, the fifth
As shown in the figure, when rubber sheets with a thickness of 1 to 2 mm are stacked over a predetermined length, an end 2A of the rubber sheets that is the lower side at the joint part (in the present invention, this is referred to as the front end) ) and the upper end 2B of the rubber sheet (this is defined as the rear end in the present invention) using a contact or non-contact method to determine the distance between the front end 2A and the rear end 2B. The amount of overlap W is measured by the front end 2A.
This is because the position of the front end cannot be determined accurately at the portion where the outer diameter changes gently, so there is a drawback that the amount of overlap cannot be measured with an accuracy of ±1 mm or more.

In addition, in the method of capturing an image of the joint part using a TV camera and processing it to determine the overlap amount W of the joint part, it takes a long time to process the image, so the pass/fail judgment result is available immediately after wrapping is completed. , which has the disadvantage of decreasing efficiency.

For example, while it takes about 2 seconds to wrap a rubber sheet around a forming drum, image processing takes 2 to 3 seconds, and during this time workers cannot move on to the next task, resulting in a significant drop in work efficiency. Become. Furthermore, the image processing apparatus has the drawback of being large-scale and expensive.

As described above, the conventional joint portion overlap amount measuring device has the drawbacks of low measurement accuracy and long measurement time.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned conventional drawbacks and to provide a device that can quickly and accurately measure the amount of overlap at a joint.

(Means and Effects for Solving the Problems) The present invention provides an apparatus for measuring the amount of overlap of a joint portion of a band member wound partially overlappingly on the circumferential surface of a drum while rotating the drum. means for detecting the amount of rotation of the drum; and means for detecting the front end of the belt-like member wound around the circumferential surface of the drum before the belt-like member is wrapped over the belt-like member; A means for detecting a rear end of the member, receiving signals from the rotation amount detecting means and the front end and rear end detecting means, determines the amount of drum rotation between the front end and the rear end of the strip member, and determines the amount of overlap. It is characterized by comprising a means for measuring.

According to the measuring device of the present invention, the front end is detected before the portion near the rear end is superimposed thereon, so that the detection accuracy is extremely high. Furthermore, since the amount of overlap is determined immediately after the rear end is detected, the measurement can be carried out quickly and work efficiency can be significantly improved.

(Embodiment) FIGS. 1A to 1C are diagrams showing the configuration of an embodiment of an overlap amount measuring device according to the present invention. In this example, the band-like member 11 is a rubber sheet used for manufacturing tires, and is wound around the circumferential surface of the forming drum 12. The forming drum 12 is driven and controlled in both directions by a reversible motor 13.

A rotary encoder 14 is attached to the rotating shaft of the forming drum 12 so that the amount of rotation can be detected. The detection output of the rotary encoder 14 is supplied to an arithmetic circuit 15 having a counter. Further, an edge detector 16 is provided near the forming drum 12 to detect the edge of the rubber sheet 11 wrapped around the forming drum 12. In this example, the rotary encoder 14 is of an incremental type, and the counter provided in the arithmetic circuit 15 is an up/down counter. The edge detector 16 is an optical analog displacement sensor that can detect the front end and the rear end without contact.

First, as shown in FIG. 1A, the forming drum 12 is moved by the motor 13.
The rubber sheet 11 is wound onto the forming drum while being rotated in the direction shown by arrow A. During this time, output pulses are supplied from the low reencoder 14, but the arithmetic circuit 150 counter does not count the output pulses until the edge detector 16 detects the edge.

When the front end of the rubber sheet 11 reaches the detection position of the edge detector 16, the edge detector 16 detects this and outputs a front end signal. This front end signal is supplied to the arithmetic circuit 15 to start the up-counting operation of the counter. The forming drum 12 is further rotated in the A direction to form the rubber sheet 1.
1 is wound around the rubber sheet, and the cutter 17 is driven at a predetermined timing to cut the rubber sheet.

In this way, as shown in FIG. 1B, the forming drum 1
A rubber sheet 11 is partially overlapped and wrapped around 2.

The amount of overlap of the overlapping joint portions is the length between the front end 11A and the rear end 11B. Next, as shown in FIG. 1C, the forming drum 12 is rotated in the opposite direction as indicated by the arrow B, and the edge detector 16 detects the trailing edge 11B of the rubber sheet 11 to generate a trailing edge signal. While the forming drum 12 rotates in the B direction, the counter of the arithmetic circuit 15 is configured to count down the output pulses of the rotary encoder 14. Therefore, by reversibly counting the output pulses from the rotary encoder 14 with the counter of the arithmetic circuit 15 after the front end 11A is detected until the rear end 11B is detected, the front end 11A is detected.
The amount of rotation from A to the rear end 11B, ie, the amount of overlap, is determined. If one output pulse from the rotary encoder 14 corresponds to the circumferential length in mm of the rubber sheet 11 wrapped around the forming drum 12, then if the final counted value of the counter is N, then the overlap amount W (mm
) can be obtained from aXN and can be output.

In this way, in the present invention, the front end 11A is detected before the rubber sheet 11 is completely wrapped around the forming drum 2, and the rear end 11B is detected after the rubber sheet 11 is wrapped. Edges can be detected with extremely high precision, and as a result, the amount of overlap can be measured accurately.

In the embodiment described above, the front end 11A and the rear end 11B of the rubber sheet 11 are detected by one edge detector 16, but in front end detection and rear end detection, the distance to the edge detector 16 is determined by the thickness of the rubber sheet. If there is a risk that the detection accuracy will decrease as a result,
Detection of the leading edge and trailing edge can be performed with separate edge detectors.

Next, an embodiment using two edge detectors in this manner will be described.

Figure 2 shows the configuration of an embodiment of the overlap amount measuring device of the present invention in which the front end and rear end of the rubber sheet are detected by separate edge detectors. Shown with a sign. In this example as well, the amount of overlap at the joint portion when the rubber sheet 11 is wound around the forming drum 12 is measured, and the rubber sheet is continuously fed by the conveyor 21. At time t, the forming drum 12 is rotated in the A direction by the motor 13.

The wrapping of the rubber sheet 11 onto the forming drum starts from.

At time t, as shown in FIG. 4A, the rubber sheet 11
The front end 11A of is detected by the front end detector 16A, and a front end signal is generated. This front end signal is sent to the gate signal generation circuit 22.
supply to. The gate signal generation circuit 22 receives this front end signal, generates a gate signal, supplies this to an up/down counter 23 that counts output pulses from the rotary encoder 14, and starts a counting operation. In this example as well, the rotary encoder 14 is constituted by an incremental encoder.

Assuming that the counter 23 counts up when the forming drum 12 rotates in the input direction, the count value of the counter starts increasing from time t1.

When the forming drum 12 is further rotated in the direction A and the cutter 17 is driven at a predetermined timing to cut the rubber sheet 11, the rubber sheet is partially overlapped on the forming drum as shown in FIG. 4B. The winding operation ends at time t2. Next, the overlapping condition at the joint portion is corrected while slightly rotating the forming drum 12 in both directions. During such an inching operation, the count value of the counter 23 repeats increases and decreases.

Next, at time t2, the correction work is completed and preparations for wrapping the next rubber sheet are started. From this time t, the motor 13 is driven in the opposite direction to rotate the forming drum 12 in the B direction. During this time, the counter 23 counts down the output pulses of the rotary encoder 14, so its count value decreases. At time t4, the rear end 11B of the rubber sheet 11 touches the rear end detector 16 as shown in FIG.
B, the rear end signal is detected at gate signal generation circuit 2.
2, the gate signal ends and the counter 23
will no longer perform counting operations. When viewed in six directions, the rear end detector 16B is located downstream of the front end detector 16A, so the counter 23 at time t4
The count value becomes a positive value D1. This value is the sum of the overlap amount W of the rubber sheet 11 and the separation distance d between the front end detector 16A and the rear end detector 168. Since this separation distance d is set in advance, the count value of the counter 13 is supplied to the calculator 24, and the count value 0. By subtracting the count value D2 corresponding to the separation distance d from , the count value N corresponding to the overlap amount W can be obtained (N=DI-02). Further, in the arithmetic unit 24, the rotary encoder 14 is applied to the count value N obtained in this way.
The amount of overlap W can be determined by multiplying the length a per pulse of (W=axN). The amount of overlap W obtained in this manner is displayed on the display 25.

The forming drum 12 is further rotated in the direction B, and at time t when the forming drum 12 reaches the state shown in the fourth diagram, the preparation for the next wrapping of the rubber sheet is completed.

In this example, a control circuit 26 is provided, which controls the motor 13.
, gate signal generation circuit 22, up/down counter 23
and controls the arithmetic unit 24 to perform the operations described above.

In this case, the detection accuracy of the front edge detector 16A and the rear edge detector 16B is reduced due to surface runout of the forming drum itself, unevenness in the joint, etc., but the front edge 11A and the rear edge 11B of the rubber sheet are detected as the front edge. Vessel 1
Since the approximate time of passing through the detection positions of 6A and rear end detector 16B can be known in advance, a time gate signal is sent from the control circuit 26 to the gate signal generation circuit 22, and the signal detected within this time gate signal is are taken in as a front end signal and a rear end signal, respectively. This makes it possible to further increase the accuracy of edge detection.

The present invention is not limited to the embodiments described above, but can be modified and modified in many ways.

In the embodiment shown in FIG. 2, an incremental type rotary encoder is used, and its output pulses are counted by an up/down counter to determine the amount of rotation of the forming drum. An absolute position display type) can also be used, and in this case, the up/down counter can be omitted.

Furthermore, although in the previous example the front and rear ends of the rubber sheet were detected using optical analog displacement sensors, other types of edge detectors may also be used.

Furthermore, in the example shown in Figure 2, the amount of overlap is calculated and the value is displayed, but it is automatically determined whether or not the amount of overlap is within the appropriate range, and only the pass/fail results are displayed. It may also be displayed. Further, in the above example, the rubber sheet is used as the band-like member, but it is also possible to measure the amount of overlap of the joint portion of another band-like member.

(Effects of the Invention) - According to the overlap amount measuring device of the present invention described above, after the band member is wound around the drum, the front end is Since the rear end is detected after the joint is configured, the front and rear ends can be measured under almost the same measurement conditions, and the detection accuracy of the front and rear ends is significantly high. The amount of overlap can be measured very accurately. In addition, since the rotation of the drum is detected by a row encoder and the overlap l is determined from the amount of rotation from the front end to the rear end, the amount of overlap can be determined immediately after the rear end is detected, and the winding of the band member can be It can be measured during a series of drum rotation operations such as joint operation and preparation for wrapping the next member.
Work efficiency will be extremely high. Furthermore, complicated data processing such as image processing is not required, measurement results can be obtained almost instantaneously, and the configuration of the device is simple and inexpensive.

[Brief explanation of the drawing]

1A to 1C are diagrams showing the configuration of one embodiment of the overlapping amount measuring device for the joint portion of a belt-shaped member according to the present invention; FIG. 2 is a diagram showing the configuration of another embodiment; FIG. 3 4A to 4D are diagrams for explaining the operation thereof, and FIGS. 5A and 5B are diagrams for explaining the conventional method for measuring the amount of overlap. 11... Rubber sheet 12... Molding drum 13...
%-414...Lower encoder 15...Arithmetic circuit 16, 16A, 16B...Edge detector 23...
Up-down counter patent applicant Brideston Co., Ltd. <('A Q Figure 3X Figure 4 BCD Figure 5

Claims (1)

[Claims] 1. In a device that measures the amount of overlap of a joint portion of a band-like member wound partially overlappingly on the circumferential surface of a drum while rotating the drum, the amount of rotation of the drum is detected. means for detecting the front end of the strip member wound around the circumferential surface of the drum before the strip member is overlaid thereon, and detecting the rear end of the strip member wrapped around the drum; and means for receiving signals from the rotation amount detection means and the front end and rear end detection means to determine the amount of drum rotation between the front end and the rear end of the strip member to measure the amount of overlap. A device for measuring the amount of overlap of a joint portion of a band-shaped member.