JP2932166B2 - Automatic inspection system for pipe dimensions of cast iron pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a large number of multi-type pipes, particularly large and medium-diameter cast iron pipes, each of which is connected to a terminal of a casting process of a cast iron pipe and continuously carried in, and each of which has a specified size. The present invention relates to a dimensional inspection device for measuring pipes.

[0002]

2. Description of the Related Art Cast iron pipes are unified with ductile cast iron in terms of material. However, in order to meet delivery dates based on contracts with local governments, an unspecified number of cast iron pipes are not limited to the same pipe type. Are cast in parallel and brought into the inspection process, so the dimensions of each cast iron tube are measured quickly, and if an anomaly is discovered, information is immediately fed back to the casting site to address the cause of the anomaly. It can not only lead to serious troubles. For that purpose, quick dimensional inspection and its accuracy are the key to quality control.

[0003] Since casting of cast iron tubes is currently all performed by centrifugal casting, if the molten metal is poured into the same mold, the product should have the same outer diameter. It is undeniable that there is a subtle difference in the cooling rate until the temperature reaches room temperature due to fluctuations and the like, and there is a possibility that a factor of the fluctuation may be included in the subsequent heat treatment. In addition, due to the special condition of the shape that the pipe length is large with respect to the diameter, there is a disadvantageous element in which distortion is particularly likely to occur in the longitudinal direction of the pipe. A limit that is dimensionally allowed by absorbing these fluctuation factors is set strictly. If the limit is exceeded, a dimensional defect is selected. Conventionally, the inspection of the dimensions of cast iron pipes has been carried out almost exclusively by inspectors.However, individual measurement is extremely inefficient and also imposes a heavy physical burden on workers. , Measurement results are not always reliable due to individual differences,
Compared to the more automated casting process, the feeling of standing behind was unavoidably problematic.

[0004] Automated attempts to mechanically replace cast iron pipe dimensions, rather than relying solely on manual work, have been undertaken. For example, in Japanese Utility Model Publication No. 4-32572, a pipe to be measured for detecting the roundness of the insertion opening of a cast iron pipe is pressed and rotated by a holding roller and a measuring roller from above and below, and the vertical fluctuation of the measuring roller is detected. The measured value of the linear scale is input to the control device and the degree of eccentricity is automatically detected. In Japanese Utility Model Publication No. 5-37206, a measuring tool is moved to automatically measure each required dimension of a socket of a cast iron pipe, and the amount of movement is counted on a pulse scale. For example the amount of movement of the measuring pin 102 to lift by operation of the cylinder 101 is detected by the pulse scale 103 and input to the controller 104 as shown in FIG. 10, be automatically calculated and the minimum inner diameter D ₃ of the socket. In Japanese Utility Model Publication No. 5-12727, a measuring unit 105 is provided at both ends of a cast iron pipe as shown in FIG. 11, and a caliper 106 which pinches a pipe body from inside and outside and pivots removably is supported in this unit. The detection value of the linear gauge 107 for detecting the rotation of both calipers is transmitted to the controller, and the thickness of the cast iron pipe is automatically measured.

Regarding the measurement of cast iron tubes, Japanese Patent Application No. 62-11878 discloses an automatic ellipse state detection of cast iron tubes.
No.6, automatic measurement of straight pipe bending condition
No. 118785, Japanese Utility Model Application No. 63-73764, and the like, to which a considerable amount of proposals have been made public and many of the prior arts are currently being implemented. Further, regarding the rationalization of measurement of cylindrical pipes other than cast iron pipes, JP-A-60-24909, which measures the axial length of a tapered portion on the inner surface of a pipe, relates to the measurement of the thickness of a circumferential butt weld such as a boiler. Showa 61-13160
JP-A-51-54452, which relates to an arithmetic process for obtaining an accurate numerical value by a simple measuring method, JP-A-1-308907, which measures the shape and defect of a steel pipe by using gamma rays,
Japanese Utility Model Publication No. 60-76209 discloses a method in which a large number of probes are radially arranged to measure the dimensions of a steel pipe.

[0006]

The prior art cited herein may be considered to have been effective in solving the problems each aimed at. However, cast iron pipes, especially large and medium diameter pipes, may be considered to be effective according to any prior art. There is still one problem that cannot be solved. As is well known, cast iron pipes are spliced together in the ground to bury long pipes, from remote reservoirs to homes at the end,
Water is sent to offices and the like, but the pipeline is not a simple straight line, and most of the time it draws a complicated curve that is bent and bent according to the road on the ground. Therefore, in forming the pipe, in addition to joining the receiving port and the inserting port of the straight pipe of a fixed size, there are cases where the direction of the cast iron pipe is changed by cutting the cast iron pipe to fit the curved path. Since the cast iron pipe used in such a case can be spliced with the mating pipe on the mating side, it is essential that the cross-sectional dimensions of the cut end always maintain a constant value regardless of the length of the cut pipe. Becomes In the industry, cast iron pipes satisfying such requirements must be separately prepared for pipe laying work, especially called "cutting pipes".

[0007] The requirements for the cutting tube are not so difficult in the case of a small-diameter cast iron tube (for example, a 75 mm diameter tube), and it can be said that all the tubes are provided. However, it is an unavoidable phenomenon that the pipe diameter increases and the dimensional error during casting is amplified, and even if it falls within the officially allowed tolerance, the difference in shrinkage due to the component difference, The cooling rate after casting and the cooling rate during heat treatment are intricately related to each other, and it is difficult to guarantee that a single cast iron pipe maintains a uniform cross-sectional dimension even when cut at any position. Since this is also a technical limitation, it detects the identity of the cross section over the entire length of the cast iron pipe, selects only the cast iron pipe that satisfies a specific numerical limit, recognizes it as a cutting pipe, and cannot satisfy it. There is a special circumstance in which the steel pipe is provided to the local market separately from other cast iron pipes.

Conventionally, the selection of the cutting tube has all been manually performed. That is, an operator places a cast iron pipe having a mixture of various diameters flowing out of a casting site at a predetermined position along the entire length of the pipe with a specific tape measure (12 stipulated by the Japan Water Works Association).
In each case, the circumference was measured to measure the circumference, and the measurement results at each position were comprehensively compared with an allowable range to perform a test. Since the work is entirely manual work, it is inefficient itself, and it is not easy to work at a very low level in terms of the relatively rationalized processes before and after, and also from the viewpoint of occupational safety and working environment. It must be said that it is serious problem that it is hard to see.

[0009] While the uniformity in each cross section required for a cutting pipe is extremely severe, the technique related to automation of measurement found in many prior arts is a method in which an inspection tool itself directly contacts the inner and outer surfaces of a cast iron pipe. This leaves considerable questions in maintaining accuracy. The cast iron pipe is made of a casting surface unique to casting in an as-cast state, and is formed of a collection surface of fine irregularities called so-called satin finish.In addition, other elements during manufacture, such as the state of the mold surface, the position in the heat treatment furnace There is a possibility that unprecedented distortion and somewhat conspicuous irregularities may be always caused by such influences, so that if a precise measuring instrument directly touches strongly, wear occurs immediately and loses accuracy. Despite the high measurement accuracy required, the surface to be measured itself is rough, and there may be distortion in the tube axis direction.
If it is too strong, the contact surface jumps or tilts, causing shock and vibration, and it is highly likely that the precise circuit of the measuring device will be disrupted or damaged, and it will be measured under the same conditions at many positions along the entire length of the pipe It is considered a difficult task to do.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a pipe dimension for most efficiently and accurately measuring the circumferential length at a number of positions over the entire length of a cast iron pipe, particularly a large-medium diameter pipe. The purpose is to provide an automatic inspection device.

[0011]

According to the present invention, there is provided an automatic apparatus for sizing a cast iron pipe according to the present invention, wherein a cast iron pipe P which is carried in and stands by is kicked one by one and placed on a pair of two rollers 11 arranged on both sides. A centering part 1 for rotating and positioning by means of a roller, and a measuring part 2 for receiving the centered cast iron pipe P on a pair of rollers 21 provided on both sides and rotating to measure the pipe outer peripheral length. And a carriage 31 reciprocating between the opposing sides of the rollers 11 and 21 and a pair of V-shaped blocks 32 and 33 opposed to each other and supported on the carriage 31 so as to be vertically movable. A touch roll sensor 4 which vertically moves up and down with respect to the pipe axis, and presses and rotates on the outer peripheral surface of each position over the entire length of the pipe just above the measuring section 2
And a rotation detector 5 for accurately detecting one rotation of the tube by detecting a rotation detector adsorbed on the outer surface of the tube with an optical fiber, and both detection values of the number of rotations of the touch roller and one rotation of the tube. It comprises a controller 6 for calculating individual circumferential lengths in the longitudinal direction of the pipe and outputting pass / fail of the dimensional inspection as compared with standard specifications. The cast iron pipes P of various sizes, which have been carried into the apparatus at random, are on standby, kicked into the centering unit 1 and enter, where they are positioned and proceed to the adjacent measuring unit 2. This movement is performed by the bogie 31 of the transport unit 3, and the bogie is moved so that the pre-measured preceding cast iron pipe P is carried out from the measuring unit 2, and at the same time, the succeeding cast iron pipe P whose centering is completed is replaced and enters. Go back and forth. Since this operation is repeated, the cast iron pipes P which are successively carried in from the casting site move in the apparatus in synchronization with the casting pace and are carried out, so that the inspection pace is remarkably improved and the problem is solved. On the other hand, in terms of the function of the measuring unit, the touch roll sensor 4 disposed on the full axis of the pipe at the same time vertically hangs down, and the touch roller 41 presses against the outer peripheral surface of the pipe to rotate. And its extension distance is detected. At the same time, the rotation detector 5 detects the rotation of the rotation detector in a non-contact manner by the optical fiber detection sensor 53 and accurately detects one rotation of the cast iron pipe P. Therefore, the total extension distance per one rotation of the pipe is calculated. The problem is solved by calculating the exact circumference at the position of at once.

In this configuration, the touch roll sensor 4
Is a polyurethane touch roller 41 having a narrow width, a long arm 43 for swingably supporting the touch roller 41 by its own weight from a fulcrum shaft 42, and a rotating shaft 44 of the touch roller 41.
The most desirable mode is to connect a pulse oscillation type rotary encoder 45 mounted on the opposite side of the above and a circuit for transmitting a pulse wave from the rotary encoder to the controller 6. The touch roll sensor has high resistance to abrasion and is not easily worn even when used, and since this method is inherently rolling friction, the abrasion effect is minimal and the detection reliability is high. If the width of the touch roller 41 is set to half or less of the normal size and the arm 43 for swingably suspending the touch roller 41 is set to 1.5 to 2 times the normal length, the outer circumference of the cast iron pipe is reduced. Even when pressed against rough casting surface or uneven surface with its own weight, it does not jump, repel or tilt, and even if there is distortion in the pipe axis direction, its fluctuation is absorbed by swinging, and each follows Since the pressure is simultaneously pressed at each position, the problem is solved because there is no fear that the fine function of the rotary encoder 45 attached to the opposite side of the shaft is impaired by impact or vibration.

The rotation detector 5 has a configuration in which a magnet 52 is held by a holder 51 so as to be able to advance and retreat toward and away from the outer peripheral surface of the cast iron pipe P, and to emit light opposing both sides of the magnet 52. Unit 53A and light receiving unit 53B
The most desirable mode is to form an optical fiber detection sensor 53 and a circuit connected to a controller 6 (CPU) that receives and processes the detection. Accurate grasp of one rotation of the cast iron pipe P is an essential premise in the present system that employs a synergistic action with the touch roll sensor. In the conventional rotation detection method, a method in which a disc is pressed against the end face (insertion) of the cast iron pipe P and rotation of the center shaft is detected by a limit switch is customary. Low repeatability and poor reliability. In addition, since the responsivity is poor in the subsequent electric circuit, reproducibility cannot be obtained, and the disadvantage that the error is larger than expected cannot be eliminated. In the present invention, the magnet 52 is adsorbed as a rotation detector on the outer peripheral surface of the cast iron tube P, rotates together with the tube, and does not come into contact with the magnet as the detector, but captures the moment of crossing by the ultrafine optical fiber detection sensor 53. And the passage of time after one rotation is processed by an electrical circuit.
The detection was the most accurate and the problem was solved by minimizing the probability of error.

In addition to the function of measuring the circumference of a cast iron tube,
A laser that advances and retreats into the tube at a fixed position at the end of the tube of the measuring unit 2, projects from a U-shaped laser oscillator 71 opposed to the tube with a gap therebetween, and calculates the tube thickness by capturing reflected waves from the inner and outer surfaces of the tube. If a configuration including a circuit for connecting the gap sensor 7 to the controller 6 is employed, the pipe wall, which is another item required for dimensional inspection, can be automatically and simultaneously inspected, further contributing to the rationalization of the entire inspection process. I do.

As for the controller 6, as shown in the block diagram of FIG. 7 showing the components of the apparatus and the information system, a high-speed counter unit 61 for counting the pulse train of the touch roll sensor 4 and an analog displacement of the laser gap sensor 7 A CP having a built-in A / D conversion unit 62 for digitally converting the value, and a separate dedicated trigger calculator 63 for counting the pulse value of the rotation detector 5 provided separately.
It is characterized by inputting to U. When measuring the circumference of a cast iron tube, the speed response of the signal that limits the range of one rotation is an important factor along with the measurement accuracy of the touch roller, and if the response of the signal is poor, the circumference is within the error. Since the measurement is performed, the measurement accuracy is consequently degraded. CPU
Since the whole device is controlled by a program, if the signal from the optical fiber is also controlled, the responsiveness will decrease.Therefore, a dedicated trigger calculator that counts only the pulse of the optical fiber sensor will be provided to improve the measurement accuracy, Make a great contribution to solving problems.

FIGS. 8 and 9 show flow charts of information processing mainly performed by the controller 6. FIG. 8 and FIG. 9 show that the amount of fluctuation accompanying the temperature change is measured by measuring another standard sample immediately before the measurement of the tube thickness by the laser gap sensor 7. In addition to measuring and calculating the correction coefficient to be absorbed, every time the measurement of the circumferential length of the touch roll sensor 4 is repeated a fixed number of times, another standard sample is measured, and the correction coefficient that absorbs the variation caused by the wear of the touch roller 41 is calculated. The procedure for measuring and calculating is a characteristic in solving the problem of the present invention. In the measurement using the laser displacement meter, the influence of the temperature causes a non-negligible error. FIG. 8 is a flow chart of the measurement of the tube thickness by the laser gap sensor 7. In the procedure of the calibration of the displacement gauge, the variation of the measured value based on the level of the air temperature is compared with a standard sample to obtain a correction coefficient. Since the correction coefficient is performed immediately before the measurement, the amount of fluctuation due to the temperature is absorbed each time, and the reliability of the measured value is increased. Similarly, FIG.
In this case, since the main cause of the measurement error is fluctuation due to the wear of the touch roller 41, a procedure for setting the parameter of the flow is incorporated, and the measurement is corrected by comparing the measured value of the standard sample at regular intervals. The coefficient is obtained and multiplied at the time of counting to improve the reliability of the measured value, and both contribute to solving the problem.

[0017]

FIG. 2 is a schematic plan view showing an entire embodiment of the present invention, and FIG. 3 is a vertical sectional front view taken along a center line of a path of a cast iron pipe. The direction in which the cast iron pipes P are carried in from the previous process is from below in FIG. 2 or from the right side in FIG. 3, and the cast iron pipes P enter the standby unit 8 one by one, and
At 1, it is kicked in a timely manner and rolls into the centering section 1 to enter. The centering portion 1 has two rollers 1 on each side.
The rolled cast iron pipe P provided with 1 is mounted thereon and supported horizontally. An adjusting plate 13 that moves horizontally by a hydraulic cylinder 12 abuts on the end surface of the cast iron pipe P, and the attitude of the pipe in the axial direction slides to a fixed position. The centering is performed with the axis aligned with the roller axis.

The transport section 3 has a carriage 31 and travels in the axial direction. Traveling is performed by the operation of the hydraulic cylinder 34 shown in FIG. The bogie 31 in the centering section 2 is sunk at a low position during the centering so as not to hinder the rotation of the cast iron pipe P. However, when the centering is completed, the axle of the wheel 35 of the bogie rotates and rises. Then, the truck rises and the V-shaped block 32 mounted on the truck becomes higher than the centering roller 11 and supports the cast iron pipe P in place of the roller 11. The trolley 31 travels while supporting the cast iron pipe P and reaches a fixed position of the adjacent measuring unit 2 where the trolley descends and the V-shaped block 32 moves.
The cast iron pipe P supported above is transferred onto the rollers 21 provided on both sides of the measuring section 2.

This movement corresponds to the area of the measuring section of the carriage 31 (FIG. 3).
At the same time), the cast iron pipe P measured on the rollers 21 is transferred to the V-shaped block 33 on the ascending trolley, moves leftward with the movement of the trolley, and moves to the left.
Move to. In this way, the operation of the centering portion on the roller and the operation of the measurement portion on the roller proceed in parallel, and when the operation is completed, the V-shaped blocks before and after the transport portion are moved up and down, and the cast iron pipe P Are simultaneously inherited and supported and moved to the next area, so that the whole forms one flow and the inspection of the cast iron tube proceeds automatically.

FIG. 1 is a layout view of the touch roll sensor 4 mounted on the measuring unit 2 so as to be able to move up and down. In this figure, a bridge 46 for suspending and supporting the touch roll sensors 4 in parallel at once is provided above a position where the pipe axis of the cast iron pipe P is divided into 12 equal parts according to a standard measurement point. The bridge 46 supporting and suspending the touch roll sensor 4 converts the rotation of the motor 47 for vertical movement into a vertical direction, and
8 to move vertically.

The detailed configuration of each touch roll sensor 4 is shown in FIGS. The touch roller 41 is swingably supported by a fulcrum shaft 42 via an arm 43 and presses against the outer peripheral surface of the cast iron pipe P by its own weight to rotate together. The fulcrum shaft 42 is screwed to the bottom surface of the bridge 46 via a bearing 49. A pulse oscillation type rotary encoder 45 is attached to the other end of the rotation shaft 44 of the touch roller 41 to replace the rotation number of the touch roller with a pulse signal,
Further, it is transmitted to the controller 6 and is electrically processed.

FIG. 5 shows a cast iron pipe P rotating in the area of the measuring section 2.
Is a rotation detector 5 that accurately detects one rotation of the rotation detector 5. A magnet 52 is applied as a rotation detector, and is held by the holder 51 and sunk below the outer peripheral surface of the cast iron pipe P at a time other than the measurement (two-dot chain line in the figure). As a result, the tip rises together with the holder 51 and the tip comes into contact with the outer peripheral surface to be sucked. Thereafter, the holder 51 separates from the magnet 52 and descends alone, and the magnet 52 rotates together with the cast iron pipe P while remaining on the outer peripheral surface. The rotation of the magnet 52 is performed by the light-emitting unit 53A and the light-receiving unit 53B which are mounted opposite to each other with the holder 51 therebetween.
Is accurately captured by the optical fiber detection sensor 53 composed of That is, when the magnet 52 starts rotating, the irradiation from the light emitting unit is interrupted and counting starts, and
Detects until the moment when light is turned off and then crossed. The signal is counted by the dedicated trigger calculator 63, input to the controller (CPU) 6, and is subjected to calculation together with the input from the touch roll sensor.

FIGS. 8 and 9 show the flow in the controller 6 as described above. The flow in FIG. 8 shows the measurement procedure by the laser gap sensor 7. Here, the calibration is a process of correcting the measurement error due to the temperature change so as to absorb the measurement error. Just before the measurement of the cast iron pipe, the standard sample having the same temperature is measured and compared to cancel the temperature factor. Also, in the information processing in the touch roll sensor 4 in FIG. 9, a correction for absorbing a fluctuation factor due to the wear of the touch roller is performed in the parameter setting process. In this case, since the progress of the wear is slow, every time immediately before the measurement. There is no need to make corrections. It is desirable from the viewpoint of preventing a decrease in productivity that a correction for each fixed number of times set empirically is input as an initial condition to the controller 6 as appropriate.

The result calculated by the CPU of the controller 6 is weighed against the permissible error limit of each pipe type input as an initial condition in advance, and the pass / fail is output to the display unit 64 and automatically displayed. Inspection record is automatically created by printing out in the format described above. Alternatively, when a certain number of pipe types continuously deviate greatly from the allowable range, it is beneficial for quality control to include a method of feeding back to the previous process using a function as appropriate, such as blinking of an alarm lamp or sounding of a siren.

FIG. 6 shows a form of a laser gap sensor 7 applied for measuring the thickness of a tube. A laser oscillator 71 having a U-shaped cross section receives an operation of an electric cylinder 72 connected below and forms a cast iron tube. From the end of the inside. In the tube, a laser beam is projected toward the inside and outside surfaces of the tube, and the reflected waves are captured and the distance L between the upper and lower oscillators and the distances S ₁ and S ₂ to the inner and outer surfaces of the tube are calculated as thickness = L− (S ₁ + S ₂ )
Is calculated by The cast iron pipe P is rotated and measured at four circumferential positions, and the results are input to the controller 6 to judge the acceptability. A circuit is provided in which all operations are electrically linked. Therefore, the workability is greatly improved, and the reliability of the result is incomparably higher. Since it is a non-contact type, it is possible to accurately measure the wall thickness without being affected by the state of the local outer peripheral surface of the cast iron pipe, and there is a possibility that the detection member itself may be worn or its function may be deteriorated due to external force (vibration, etc.). It has no advantages.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS It is needless to say that there is no limitation on the type of cast iron pipe to be subjected to the automatic inspection apparatus of the present invention, but as mentioned above, the concept of selecting a cutting pipe is unnecessary for a small diameter pipe. However, since the large diameter pipe is used for the main trunk line and the pipe length itself is short, the necessity as a cutting pipe is small, so the most effective embodiments are all medium diameter pipes, that is, 300 to 800.
A cast iron tube of about mm is mainly used. To give an example of this type of tube, the touch roller 41 of the touch roll sensor 4 is made of a polyurethane disc having a diameter of 100 ± 0.1 mm, and the width of the roll is 30 mm, and the width of the roll is 30 mm. Set to less than half. In addition, the distance between the rotation shaft 44 of the touch roller and the fulcrum shaft 42 is set to 270 mm, which is x times longer than the standard length of the conventional arm. By modifying these dimensions, the touch roller has previously jumped up and down, or has been tilted on the measurement surface, preventing accurate touching. 1.7 Kgf / cm ² smoothly pressed and co-rotated.
Regarding the rotary encoder 45, the pulse frequency was up to 750 in the conventional standard equipment,
The capacity was greatly increased to 1024 ppr, and a high-speed and high-precision rotary encoder was formed.

Regarding the rotation detector, the accuracy cannot be obtained by the conventional technology of the limit switch system, and even if the accuracy is confirmed by combining this system with the touch roll sensor,
An error of about 2 mm is inevitable for a circumferential length of 250 x π, and the error range is not specified and the reproducibility is poor and unreliable. The total error was within the error range of 0.16 mm, and a remarkable improvement in the inspection level was demonstrated along with its outstanding reproducibility. After all, 300-800m
± 0.3m on average for medium diameter cast iron pipes
It has been confirmed that the error is kept within the error range of m or less, and the ratio has an amazing accuracy of 0.3 / (800 × π) = 0.012%. Originally, in the cast iron tube itself, surface irregularities, ellipses, distortions, bending, and the like are unavoidable. Therefore, even if it is estimated that the accuracy is reduced by a factor of two in consideration of the factors of the variation, the maximum error is ± 0.6 mm. This proved to be sufficient.

For measuring the wall thickness of a pipe, for example,
In the case where the measurement was carried out directly by hand using a caliper with the tube in place, the accuracy was limited by experience to an error of about 1/10 mm, but the error range up to 1/100 mm in the non-contact type laser beam projection method Was reduced, and the accuracy was outstanding.

[0029]

The apparatus for automatically inspecting the size of a cast iron pipe according to the present invention is applicable to an outer peripheral surface which is a casting surface having a relatively rough inspection surface, and has an extremely high inspection accuracy as compared with the prior art.
In addition, since the function is maintained for a long time and hardly changes, the reliability of the inspection result is much higher than before. In particular, it is suitable for sorting so-called cutting pipes of medium diameter pipes, and if it is limited to measuring the circumference at multiple points in the pipe axis direction required as a requirement, efficiency of inspection that could not be achieved by any conventional technology It will make a great contribution to transforming the workplace into a highly efficient and comfortable workplace by eliminating various problems at the site, such as streamlining, labor saving, purification of work environment, and solving occupational safety and hygiene problems. Another feature of the present invention is that, in addition to the development and combination of unique inspection methods, the overall excellent inspection layout further contributes to this effect. In response to the current situation where an unspecified number of cast iron tubes are flowing in by setting a reasonable area, the effect of smoothly handling and forming a smooth flow is great, and a new inspection capability that can follow the automation of casting work is newly added. Providing is the driving force that increases the productivity of the entire production process.

The second aspect of the present invention relates to a specific correspondence of the touch roll sensor. The touch roll sensor itself is a known technique conventionally applied to the measurement of the thickness of papers and cloths. The problems that could not be applied to a perfect casting surface were identified and improved as a result. As a result, the effect of reaching an inspection method having both excellent accuracy and durability was great.

Claim 3 relates to a specific correspondence of the rotation detector, and it can be said that a detection method itself in which a rotation detector is attached to an inspection surface and a moment when the rotation detector is crossed by an optical fiber detection sensor by movement is known. The combination and operation of various members attached to detect one rotation of a cast iron tube is based on a novel idea which cannot be seen in the prior art. By combining with a touch roll sensor, the inspection flow itself should be regarded as building a factor which produces the above-mentioned effect which cannot be obtained by the conventional individual technology.

A fourth aspect of the present invention relates to a concrete form relating to the thickness measurement of a cast iron pipe. The improvement of efficiency and the securing of reliability are remarkable by non-contact type measurement. The effect of the development of the pioneer is remarkable.

According to a fifth aspect of the present invention, a dedicated pulse counter unit is provided in the rotation detector to prevent a decrease in responsiveness, and as a result, the measurement accuracy of the entire apparatus is greatly improved. Also,
Claim 6 has the effect of incorporating the unique correction procedure of the present invention into a normal measurement flow, eliminating the cause of the occurrence of a specific error, and greatly increasing the reliability of the measured value. It greatly contributes to speeding up and improving accuracy.

[Brief description of the drawings]

FIG. 1 is a front view showing a main part of a measuring unit in an embodiment of the present invention.

FIG. 2 is a plan view showing the entire embodiment.

FIG. 3 is a front view at the center vertical section in the upper figure.

FIG. 4 is a front view (A) and a plan view (B) of a touch roll sensor.

FIG. 5 is a front view of a rotation detector.

FIG. 6 is a front view (A) and a measurement principle (B) of a laser gap sensor for measuring a pipe thickness.

FIG. 7 is a block diagram of the present invention.

FIG. 8 is a flow chart of the tube thickness measurement of the present invention.

FIG. 9 is a flowchart of measuring the circumference of the present invention.

FIG. 10 is a partial cross-sectional front view of the prior art.

FIG. 11 is a front view of another prior art.

[Explanation of symbols]

 1 Centering section 2 Measuring section 3 Transport section 4 Touch roll sensor 5 Rotation detector 6 Controller (CPU) 7 Laser gap sensor 8 Standby section 9 Unloading section 11 Roller 21 Roller 31 Cart 32 V-shaped block 33 V-shaped block 41 Touch Roller 42 Support shaft 43 Arm 44 Rotation axis 45 Rotary encoder 51 Holder 52 Magnet 53 Optical fiber detection sensor 61 High-speed counter unit 62 A / D conversion unit 63 Dedicated trigger calculator 64 Display unit 71 Laser oscillator P Cast iron tube

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takafumi Utsumi 925-2 Yoneda, Yoneda-cho, Takasago-shi, Hyogo Takasago Urban Comfort 103 (56) References JP-A-54-61563 (JP, A) Japanese Utility Model Showa 63-92209 (JP, U) Japanese Utility Model Hei 1-97208 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) G01B 21/00-21/30 B22D 11/16

Claims (6)

(57) [Claims] 1. An apparatus for inspecting a pipe size of a cast iron pipe, in which a cast iron pipe P which is carried in and stands by is kicked one by one and rotated and positioned on a pair of two rollers 11 arranged on both sides, respectively. A centering portion 1, a measuring portion 2 for receiving the centered cast iron pipe P on a pair of rollers 21 provided on both sides and rotating to measure the pipe outer peripheral length, and the rollers 11, 21 Bogie 3 reciprocating between both sides facing
1 and 2 that are opposed to each other on the carriage 31 and supported so as to be able to move up and down.
A pair of V-shaped blocks 32 and 33 are arranged in series and arranged in a conveying section 3. The conveying section 3 is arranged directly above the measuring section 2 and vertically moved up and down with respect to the tube axis. A touch roll sensor 4 which rotates by pressing, a rotation detector 5 which detects a rotation detector adsorbed on the outer surface of the tube with an optical fiber and accurately detects one rotation of the tube, a rotation number of the touch roller and a rotation speed of the tube. A cast iron pipe comprising a controller 6 for inputting both detected values of rotation to calculate a circumferential length at each position in the longitudinal direction of the pipe, and outputting pass / fail of dimensional inspection in comparison with standard specifications. Automatic tube dimension inspection equipment. 2. The touch roll sensor 4 according to claim 1, wherein the touch roll sensor 4 includes a narrow touch roller 41 made of polyurethane, a long arm 43 for swingably supporting the touch roller 41 from a fulcrum shaft 42 by its own weight, and Rotary shaft 4 of roller 41
An automatic pipe size inspection apparatus for a cast iron pipe, comprising: a pulse oscillation type rotary encoder 45 mounted on the opposite side of the pipe 4 and a circuit connected to a controller 6 for receiving and processing the detection. 3. The rotation detector 5 according to claim 1, wherein the rotation detector 5 is opposed to the magnet 52 held by the holder 51 so as to be able to advance and retreat and to be detachable toward the outer peripheral surface of the cast iron pipe P on both sides of the holder 51. Light emitting section 53A and light receiving section 53B
1. An automatic pipe size inspection apparatus for a cast iron pipe, comprising: an optical fiber detection sensor 53 comprising a microsequencer for receiving and processing the detection, a high-speed counter, and a circuit connected to the controller 6 via a main sequencer. 4. The tube according to claim 1, wherein the measuring portion 2 projects into and out of the tube at a fixed position at the end of the tube from a U-shaped laser oscillator 71 which faces the tube with a tube wall therebetween. An automatic pipe size inspection apparatus for a cast iron pipe, comprising a circuit for connecting a laser gap sensor 7 for calculating a pipe wall thickness by capturing a reflected wave from an outer surface to the controller 6. 5. The controller according to claim 1, wherein the controller 6 is a high-speed counter unit 61 for counting a pulse train of the touch roll sensor 4 and an A / D for converting an analog displacement value of the laser gap sensor 7 into a digital signal. A dedicated trigger calculator 63 for counting the pulse value of the rotation detector 5 which comprises a CPU incorporating the conversion unit 62;
And an input to the CPU separately. 6. A method according to claim 5, wherein a correction coefficient for absorbing a variation due to a temperature change is measured and calculated by measuring another standard sample immediately before the measurement of the tube thickness by the laser gap sensor. An automatic pipe size inspection apparatus for a cast iron pipe, wherein another standard sample is measured each time the circumferential length measurement is repeated a fixed number of times, and a correction coefficient for absorbing a variation caused by wear of the touch roller 41 is measured and calculated. .