JPS6298210A - Dimension measuring instrument for mobile object - Google Patents

Abstract

PURPOSE:To measure dimensions in the mobile direction of a high-speed object based on a difference in level by sampling signals from displacement sensors and detecting sample values in order changing monotonically the prescribed times and deciding it to be the difference in level. CONSTITUTION:A rotating roller of a rotary encoder 3 is brought into contact with the surface of a rubber cord 1 and a pulse corresponding to conveyance of the cord 1 is generated. Further, optical displacement sensors 4 and 5 are arranged in order to detect the difference in level 1b and 1c of a stuck part 1a of the cord 1. Then, output signals of the sensor 4 and 5 are sent to a signal processing circuit 6 and sampled respectively by an A/D converter and the samples are sent in order to a CPU. The CPU detects it as the difference in level in case these samples are changed monotonically continuously prescribed times. Then, the pulses outputted from the encoder 3 in the course from detecting the difference in level 1b till detecting the difference in level 1c are optionally counted. Then, the length of the stuck part 1a is calculated by multi plying the obtained counted value by the unit length per pulse.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for measuring the dimensions of an object, and particularly to an apparatus for measuring the dimensions of an object in a moving direction in a non-contact manner.

(Prior art) Conventionally, for example, the amount of bonded joints of rubber cords used in the manufacture of tires, that is, the length of the joint portion measured in the longitudinal direction of the rubber cords, has been measured by Probes are brought into contact with the upper and lower surfaces, and steps are detected based on the vertical movement of these probes. For example, between detecting the upper step and lower step, the rubber This was done by measuring the distance the cord was transported.

(Problems to be Solved by the Invention) The conventional measuring device described above has the disadvantage that the rubber cord cannot be moved at high speed because the probe needs to be in constant contact with the rubber cord that is the object to be measured. was there. The conveyance speed of the rubber cord in the tire manufacturing process is extremely high, and it is difficult to accurately detect displacement due to a step by bringing a probe into contact with the rubber cord moving at such high speed.

Furthermore, as described above, the rubber cord conveyed at high speed is prone to meandering and waving phenomena, and the probe is affected by such abnormal movements, making it even more difficult to detect differences in level.

It is also possible to use a non-contact displacement sensor, for example an optical displacement sensor, instead of a contact displacement sensor, but the output signal supplied from such a displacement sensor has large fluctuation components as shown in Figure 3. For example, there is a drawback that it is not possible to accurately detect a stepped portion by comparing it with a fixed limit level.

An object of the present invention is to eliminate the above-mentioned drawbacks and provide a dimension measuring device for a moving object that can accurately measure the dimension in the moving direction by accurately detecting the stepped portion of an object moving at high speed without contact. This is what I am trying to do.

(Means for Solving the Problems) The dimension measuring device of the present invention includes a conveyance device that conveys an object to be measured in a predetermined direction, a device that generates a pulse signal synchronized with the conveyance by this conveyance device, and a conveyance device. A displacement sensor that non-contactly detects the distance to an object being conveyed and outputs a distance signal; The object is characterized by comprising a signal processing circuit that outputs a signal for determining that there is a step, counts the pulse signals based on the step judgment signal, and measures the dimension of the object in the moving direction based on the step. It is something to do.

(Function) In the above-mentioned dimension measuring device of the present invention, it is possible to detect step portions of an object without contact, so the object can be moved at high speed, and the distance signal obtained by sampling the distance signal can be detected in a non-contact manner. Since the step is determined by detecting that the sample value changes continuously and monotonically a predetermined number of times, it is possible to accurately identify the step even if the distance signal detected non-contact contains a fairly large fluctuation component. can be detected.

(Embodiment) FIG. 1 is a perspective view showing the configuration of an embodiment of a dimension measuring device according to the present invention, and in this embodiment, the length of a bonded portion of rubber cords is measured.

The rubber cord 1 is conveyed by a roller conveyor 2 in the direction indicated by arrow A. A rotating roller of a row reencoder 3 is brought into contact with the surface of the rubber cord 1 to generate pulses corresponding to the conveyance of the rubber cord. As usual, the rotary encoder 3 is connected to the rubber cord 1 at a predetermined distance.
For example, since N pulses are generated every time the rubber cord is moved by 1 weight, it is possible to generate pulses corresponding to the amount of movement of the rubber cord, regardless of the conveying speed of the rubber cord. As shown in FIG. 1, steps 1b and 1c are formed in the bonded portion 1a of the rubber cord 1, and the length of the bonded portion is measured as the distance between these steps. In order to detect the steps 1b and 1c without contact, first and second optical displacement sensors 4 and 5 are arranged above and below the conveyance path of the rubber cord 1. In FIG. 1, these displacement sensors 4 and 5 are arranged in alignment in a direction perpendicular to the conveyance path of the rubber cord, but this is not necessarily necessary, and these displacement sensors may be arranged offset in the conveyance direction. You can also. The above-mentioned low reencoder 3 and the first. The output signal of the second displacement sensor 4.5 is supplied to the signal processing circuit 6.

FIG. 2 shows a detailed configuration of the signal processing circuit 6. As shown in FIG. After the output signals of the first and second displacement sensors 4 and 5 are amplified by amplifiers 7 and 8, they are sampled in A/D converters 9 and 10 using appropriate sampling signals, such as pulses supplied from the rotary encoder 3. Convert it to a digital signal and use a digital arithmetic unit (CPU)
11. This digital arithmetic unit 11 is also supplied with pulses from the rotary encoder 3. The digital calculator 11 detects the steps 1b and lc of the rubber cord 1 using a method described later, and calculates the distance between these steps as the product of the pulse count from the rotary encoder 3 and a predetermined coefficient. demand. The length of the rubber cord bonded portion 1a measured in this way is displayed on the display device 12.
Displayed by

Next, the operation of the above-mentioned apparatus will be explained with reference to the signal waveform diagram in FIG. 3 and the flowcharts in FIGS. 4 and 5.

The output signals supplied from the displacement sensors 4 and 5 contain many fluctuating components, as shown in FIG. 3, and it is difficult to detect the steps 1b, lc of the rubber cord 1 as they are. Therefore, these output signals are sent to the A/D converter 9.
and 10 to obtain sequential sipeles, which are supplied to the arithmetic unit 11. The arithmetic unit 11 detects a step when these samples continuously change monotonically a predetermined number of times. According to such signal processing, it is possible to detect a level difference without error even when a large fluctuation component is included as shown in FIG.

In this way, the upper level difference detection signal S is generated from the output of the displacement sensor 4, and this causes the low-level encoder 3
Reset the counter that counts the pulses supplied from and start counting. This count is the displacement sensor 5
It stops when the lower level difference detection signal S2 is detected from the output. Therefore, the counter selectively counts the pulses output from the rotary encoder 3 during the period from when the upper step 1b is detected to when the lower step 1c is detected. This count value corresponds to the distance that the rubber cord 1 has moved during the above-mentioned period, and therefore corresponds to the length of the bonded portion 1a of the rubber cord 1 expressed as the distance between the two lids. That is, the length of the bonded portion 1a can be determined by multiplying the count value obtained in this way by the unit length per pulse.

FIG. 4 is a flowchart showing the entire operation described above in the arithmetic unit 11. After the start, it is determined whether or not to take in data, and then the output of the displacement sensor 3 is taken in via the A/D converter 9, and the upper step Determine whether or not. This determination is made according to the subroutine shown in FIG. That is, after clearing the counter that counts the number of samples, the previous sample Dn supplied from the A/D converter 9
The difference, -Dfi, between -+ and the sample D, .

On the other hand, if the above difference is not greater than X, it is determined that the process ends, the sample number counter is cleared again, and the above-described operation is repeated. The count value of the sample number counter is compared with a predetermined number Y, for example "3", and if n>Y, then
Compare the next sample with the previous sample and determine if the difference is greater than X. As shown in FIG. 3, since the samples in the upper step 1b are monotonically decreasing, the sample number counter continuously counts, and the counted value n becomes larger than Y. When n>Y in this way, a step detection signal is output.

On the other hand, if the count value n of the sample number counter becomes thicker than Y (Dn-, -D, l≦X), this counter is cleared and no step detection signal is output.

The value of the limit count value Y can be determined experimentally by taking into account the sampling frequency, the operating characteristics of the displacement sensor, the characteristics of the object to be tested, and the like.

The lower level difference 1c can be detected using a similar method, but since it increases monotonically as shown in FIG. 3, it is sufficient to determine whether D, -D, or I>X.

The present invention is not limited to the embodiments described above, but can be modified in many ways. For example, in the above embodiment, displacement sensors were placed above and below to measure the length of the bonded part of the rubber cord. In the case where the displacement sensor is to be detected, the displacement sensor may be provided facing one surface. Further, in the above-described embodiment, the distance between steps is measured, but the present invention can also be applied to various applications in which dimensions in the moving direction are measured using the steps as a reference. Further, in the above-described embodiment, the rotary encoder is brought into contact with the running rubber cord to generate pulses proportional to the running distance, but similar pulses can also be generated from a conveying device such as a roller conveyor.

(Effects of the Invention) According to the above-mentioned dimension measuring device of the present invention, dimensions can be measured without contact, so the length of the bonded portion of a rubber cord conveyed at true speed can be measured. ,
Quality control on the production line becomes possible. Level differences are detected by sampling the output signal from the displacement sensor and detecting that the successive samples change monotonically over a predetermined number of times, so large fluctuations in the output signal of the displacement sensor are detected. Even if components are included, steps can be detected accurately, and as a result, dimensions can be measured accurately.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the overall configuration of an embodiment of a dimension measuring device according to the present invention, FIG. 2 is a block diagram showing the configuration of an example of a signal processing circuit thereof, and FIG. 3 is a diagram showing signals in the signal processing circuit. The waveform diagrams, FIGS. 4 and 5 are flowcharts showing signal processing operations in the signal processing circuit. 1.-Rubber cord 1a... pasting part lb
, lc...Step 2...Roller conveyor 3...Rotary encoder 4.5...Displacement sensor 6...Signal processing circuit 7
．． 8...Amplifier 9,1o...A/D converter 11...Arithmetic unit 12...Display device patent applicant Brideston Co., Ltd. Figure 1, Figure 2

Claims (1)

[Claims] 1. A conveyance device that conveys the object to be measured in a predetermined direction, a device that generates a pulse signal synchronized with the conveyance by this conveyance device, and a distance measurement device that detects the distance to the object conveyed by the conveyance device in a non-contact manner. A displacement sensor that outputs a signal, samples this distance signal, and outputs a signal that determines that there is a level difference in the object when it detects that the sequential sample values change monotonically a predetermined number of times, and uses this level difference determination signal. and a signal processing circuit that counts the pulse signals based on the height difference and measures the dimension of the object in the moving direction with respect to the step.