JPH10185506A - Method and device for detecting position of buried reinforcing bar in alc panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the position of a reinforcing bar buried in an ALC panel by detecting the amplitude variation of electrical oscillations from an eddy- current displacement sensor by bringing the sensor nearer to the header face of the panel while the panel is carried on its production line. SOLUTION: A panel position detector 5 detects an ALC panel when the panel 1 arrives at a prescribed position while the panel 1 is carried on a transporting device 8. Then a sensor moving device 9 brings an eddy-current displacement sensor 7 nearer to the header face 4 of the panel 1 based on the detect signal of the detector 5 and the sensor 7 detects the covering depth of a reinforcing bar (auxiliary bar) 2 from the header surface of the panel 1. When the covering depth is detected, a device for detecting position of buried reinforcing bar in ALC panel outputs some signal in accordance with the detected covering depth, whether or not the depth is smaller than a prescribed value, for informing the defectless/defective condition of the panel 1. When it is detected that the covering depth of the bar 2 is a specified value, the sensor returns to the original position by leaving the header face 4 of the panel 1 behind and waits for the next panel to be carried in.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects whether or not a reinforcing bar (sub-bar) embedded in an ALC panel is located at a predetermined position from a fore face of the panel while the ALC panel is being conveyed on a production line. The present invention relates to a method and an apparatus for detecting a buried position of a reinforcing bar of an ALC panel.

[0002]

2. Description of the Related Art In FIG. 4, an ALC panel (hereinafter, referred to as a panel) 1 has a distance from a small face 4 to a reinforcement reinforcing bar (secondary reinforcing bar 2) embedded therein (hereinafter referred to as a sub-type from the panel small face). If the covering thickness T is not within the predetermined length, the end of the panel 1 hanging on the beam becomes insufficient in strength, especially when used as a roof or floor panel, which is serious in terms of safety such as dropping of the panel 1. It becomes a problem. Therefore, conventionally, the following method has been known in order to inspect the cover thickness T of the accessory bar from the edge of the panel. That is, as shown in FIG. 4, as a first method, the rod pin hole 21 and the secondary bar 2 are determined based on the distance L2 between the rod pin hole 21 formed for suspending the reinforcing bar composed of the reinforcing bars 2 and 3 and the front face 4 of the panel. Subtract the distance L1 that is a constant value in manufacturing to the center of
The cover thickness T of the accessory bar from the front edge of the panel was determined.

[0003] Alternatively, as a second method, Japanese Patent Laid-Open No. 6-2
As disclosed in Japanese Patent No. 94873, a magnet 22a is fixed to the tip of a spring member 22b of the reinforcing bar position detector 22 in FIG.
There is a method of converting the distortion of the spring member 22b, which occurs when it comes close to the sub-reinforcement 2 in the panel 1, into an electric signal by a strain gauge, and measuring the distance between the panel front face 4 and the sub-reinforcement 2 from the size. Was.

[0004]

However, the reinforcing steel bar 2,
When the hanging rod pin comes off due to some trouble while the cage 3 is in a cage state, and the reinforced cage falls off, a panel without reinforcing steel may be finally completed. However, since the rod pin hole 21 is vacant in the panel manufactured in this way, the first method described above has a problem that it is not possible to detect that the reinforcing bar is not embedded in the panel. In addition, if there was an error in the distance L1 that should be a constant value in manufacturing between the rod pin hole 21 and the center of the accessory streak 2, an accurate cover thickness T of the accessory streak from the panel front face could not be obtained.

Further, in order to accurately measure the cover thickness T of the accessory bar from the panel edge by the second method, the rebar position detector 22 is arranged in parallel with the panel edge 4 (in FIG. 5, the vertical direction of the arrow). ), The magnet 22a is attracted to the accessory bar 2 and the spring member 22b is most distorted (the output of the electric signal is largest), that is, the rebar position detector 2
It was necessary to find a position where the second magnet 22a was directly above the accessory muscle 2 (in FIG. 5, right beside the accessory muscle 2).

Therefore, even if this is used for a production line,
When the panel 1 having a different cover bar cover thickness H from the surface of the panel 1 is conveyed, the position of the sub bar 2 in the thickness direction of the panel 1 is not known, and the fixed rebar position detector is fixed. In 22, since there is no magnet 22 a directly above the accessory bar 2, the cover thickness T of the accessory bar from the wrong panel edge is measured, or the rebar position detector 22 is always moved in parallel with the panel edge 4. It is necessary to detect the position of the accessory muscle 2 while searching for a position directly above the accessory muscle 2, and in effect, measure the cover thickness T of the accessory muscle from the panel edge surface by this method while transporting the panel 1. Things were difficult.

Accordingly, the present invention provides a reinforcing reinforcing bar for a panel which can easily detect whether or not the cover thickness T of a sub-reinforcing bar is at a predetermined length from the panel foreground while conveying the panel 1 on a production line. It is an object of the present invention to provide a method and an apparatus for detecting an embedded position of a (secondary muscle).

[0008]

According to a first aspect of the present invention, an eddy current type displacement sensor is provided on a small surface of a panel while the panel is being conveyed on a production line. A method of detecting the embedment position of a reinforcing bar of a panel is provided by detecting a change in amplitude or phase of electric oscillation from the eddy current type displacement sensor by approaching the reinforcing bar to detect a reinforcing bar embedded in the panel.

An apparatus for carrying out the method of claim 1 includes an eddy current displacement sensor for detecting a reinforcing bar embedded in a panel, a panel position detecting device, and a panel position detecting device. A sensor moving device for bringing the eddy current displacement sensor closer to the panel fore face when the position of the eddy current type displacement sensor is detected, and a head for the eddy current displacement sensor for bringing the eddy current type displacement sensor closer to the panel fore face And a guide roller for maintaining a constant distance between the panel and the front edge of the panel.

The operation of the present invention will be described below. In the present invention, the eddy current displacement sensor 7 is used as a method for detecting the cover thickness T of the accessory muscle from the panel edge surface. this is,
In general, it is said to be a high frequency induction type, and the sensor part is LC
The high frequency magnetic field is generated from the ferrite core in the detection direction, and if a conductive metal object enters this magnetic field, an eddy current will be generated on the surface of the nearby object and equivalently oscillate. This is equivalent to a load hanging in the circuit, the Q of the oscillation circuit is reduced, and the oscillation stops. Therefore, in the present invention, in order to detect the cover thickness T of the accessory muscle from the panel edge surface,
When the eddy current type displacement sensor 7 approaches the proximity body (the auxiliary muscle 2 in the panel) from the panel edge 4 side, the phenomenon that the amplitude or phase of the electric oscillation changes or the oscillation stops is used.

Further, the eddy current displacement sensor 7 can have a large surface area for sensing the approaching auxiliary muscle 2 from its structure. Thereby, in FIG. 2, the auxiliary muscle 2 is connected to the eddy current type displacement sensor 7.
If the cover H does not deviate from the surface (head 7a) for sensing the metal body, the cover thickness H of the spike from the surface of the panel 1 changes depending on the type of the panel 1, and even if the spike 2 moves up and down in the figure, the panel edge The cover thickness T of the accessory muscle from the surface can be accurately detected.

In the conventional reinforcing bar position detector 22 using the magnet 22a, the cover thickness T of the sub-reinforcement from the panel foreside is measured while moving parallel to the panel foreside 4 and searching for a position right above the sub-reinforcement 2. Although it was necessary to measure, by employing this eddy current type displacement sensor 7, there was no need to search directly above the accessory muscle 2 which is not known where it was buried. The cover thickness T of the accessory streaks from the panel edge can be detected only by bringing the panel 7 closer.

This makes it easy to detect even the panel 1 being transported. Furthermore, by approaching the eddy current type displacement sensor 7 along the panel edge 4 being conveyed, the cover thickness T of the accessory streaks from the panel edge is continuously changed over the entire panel edge 4 instead of at one point. Can be detected.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, first, the panel position detecting device 5 detects the panel 1 which has been transported on the transport device 8 and has reached a predetermined position. Next, based on the detected signal, the sensor moving device 9 causes the eddy current type displacement sensor 7 to approach the panel fore face 4, and the eddy current type displacement sensor 7 covers the accessory muscle from the panel fore face. The thickness T is detected. At this time, depending on whether or not the cover thickness T of the accessory streaks 2 from the panel edge 4 is within a predetermined length, the device outputs some signal to notify whether or not the panel is defective. When it is detected that the cover thickness T of the accessory muscle from the panel fore face is a predetermined length, the eddy current type displacement sensor 7 returns to the original position away from the panel fore face 4 and another panel 1 is moved. Wait until it is transported.

According to the above-described detection method, all detection (inspection) can be performed automatically, so that there is no need for inspection personnel and no human error.
Since all inspections can be easily performed, safety quality can be ensured. Furthermore, since the cover thickness T of the auxiliary streaks from the panel edge can be detected without stopping the transfer device, the production efficiency of the panel 1 increases. Moreover, even if panels 1 having different cover bar cover thicknesses H from the surface of the panel 1 are mixed and flow on the transport device, the cover cover cover thickness T of the sub bar from each panel edge surface is obtained.
Can be detected correctly.

Next, the device of the present invention will be described. The device of the present invention includes a panel position detecting device 5, an eddy current displacement sensor 7, a sensor moving device 9, and a guide roller 6. As described above, the eddy current type displacement sensor 7 in the present invention employs the high frequency induction type, and the oscillation stops when the eddy current type displacement sensor 7 approaches the accessory muscle 2 in the panel 1 from the side of the small face 4 of the panel. Utilize the phenomenon that you do.

The eddy current type displacement sensor 7 detects the cover thickness T of the sub-reinforcement from the front edge of the panel even in the panel 1 of the type in which the cover H of the sub-reinforce from the surface of the panel 1 in FIG. 2 is different. Has features that can.

As the panel position detecting device 5, various detecting devices using a limit switch, an ultrasonic sensor, a capacitance sensor and the like can be applied. Above all, laser photoelectric switches are most desirable.

The sensor moving device 9 for bringing the eddy current type displacement sensor 7 close to the panel front face 4 can be various types such as a ball screw, a servo motor, a motor drive cylinder, and a hydraulic cylinder, but the air cylinder has a simple structure. It is more preferable in terms of size and cost.

Further, the guide roller 6 is arranged in parallel with the eddy current type displacement sensor 7 so that the head 7a of the eddy current type displacement sensor 7 does not wear due to contact with the panel edge surface 4. At this time, the sensor moving device 9 for approaching the panel edge 4 presses the eddy current displacement sensor 7 against the panel edge 4. A constant gap G is always kept between them. For this reason, the dimensional fluctuation of the gap G is eliminated, and the distance between the head 7a of the eddy current displacement sensor 7 and the auxiliary muscle 2, and finally, the cover thickness T of the auxiliary muscle from the panel edge surface from which the gap G dimension is subtracted. Is detected without error.

In order to prevent the head 7a of the eddy current type displacement sensor 7 from coming into contact with the panel edge 4 to prevent abrasion or breakage, or to obtain a sufficient detection sensitivity, the gap G is set to 0.3 mm or more. Preferably, it is set to 1 mm. Further, the material of the guide roller 6 is preferably a synthetic resin material which has little abrasion and rolls tightly without slipping on the panel edge surface 4, and is preferably wear-resistant nylon.

[0022]

Next, the apparatus of the present invention will be described in detail with reference to more specific examples. As shown in FIGS. 1 and 3, the reinforcing bar burying position detecting device 13 of the present embodiment includes an eddy current displacement sensor 7, a panel position detecting device 5 using a laser photoelectric switch, and the panel position detecting device. 5, a sensor moving device 9 using an air cylinder for bringing the eddy current displacement sensor 7 close to the panel front face 4 when the position of the panel 1 is detected, and bringing the eddy current displacement sensor 7 close to the panel front face 4 In this case, a guide roller 6 made of wear-resistant nylon is used to keep the distance between the head 7a having a diameter of 100 mm of the eddy current type displacement sensor 7 and the front face 4 of the panel constant.

In this embodiment, the panel position detecting device 5, the eddy current displacement sensor 7, and the guide roller 6 are mounted on the same steel plate 14 to reduce the size of the device.

Next, the operation of the embedment position detecting device 13 for reinforcing bars of this embodiment will be described with reference to FIGS.
First, the panel position detecting device 6 of the laser photoelectric switch
Detects the panel 1 that has been transported on the transport device 8 and has come to a predetermined position. Next, based on the detected signal, air
A sensor moving device 9 using a cylinder causes the steel plate 14 on which the eddy current type displacement sensor 7 and the guide roller 6 are mounted to approach the panel front surface 4. Then, the eddy current type displacement sensor 7 detects the cover thickness T of the auxiliary muscle from the panel edge surface.

At this time, the guide roller 6 made of abrasion-resistant nylon, which is mounted on the steel plate 14 together with the eddy current type displacement sensor 7, comes into contact with the panel edge surface 4 and rolls, so that the eddy current type displacement sensor is provided. Since the head 7a and the panel edge 4 are kept at a constant distance, the gap G does not fluctuate. As a result, the distance detected by the eddy current displacement sensor 7 between the head 7a of the eddy current displacement sensor 7 and the accessory muscle 2 is determined by setting the gap G to the allowable thickness T of the accessory muscle from the panel edge. The added value may be set as a threshold.

In the present embodiment, the cover thickness T of the accessory streaks from the panel edge to be detected is 33 mm, and the gap G is 0.5
mm, the threshold value of the distance detected by the eddy current displacement sensor 7 was set to 33.5 mm. Also,
The reinforcing bar 2 used was a reinforcing bar having a diameter of 5 mm.

Then, as shown in FIG. 1, the sensor control amplifier 10 amplifies the detection signal of the eddy current displacement sensor 7. Further, based on the signal, the control device 1
1 judges whether the cover thickness T of the accessory line from the fore edge is within a predetermined length, and sounds an alarm buzzer 12 if the defective panel has no accessory line 2 at a predetermined length. After detecting the accessory muscle 2 within a predetermined length, the steel plate 14 on which the eddy current type displacement sensor 7 is mounted by the sensor moving device 9 of the air cylinder is separated from the panel edge 4 and returns to the original position. return,
It waits until another panel 1 is conveyed. In the steps described above, the conveyance of the panel 1 is not stopped in order to detect the cover thickness T of the accessory streaks from the panel fore edge.

In this embodiment, the head 7a has a diameter of 10 mm.
Since the eddy current type displacement sensor 7 having a circular surface as large as 0 mm is employed, even if the cover 1 having different cover bar thicknesses H of 15 mm and 25 mm from the surface of the panel 1 shown in FIG. In addition, the cover thickness T of the accessory muscle from the front edge of the panel could be correctly detected.

[0029]

According to the present invention, it is possible to determine the cover thickness of the sub-reinforcement from the panel edge and the presence or absence of the reinforcing bar even in the case of panels of different types in which the cover-reinforcement from the panel surface is different from the panel surface while being conveyed on the panel production line. All the panels could be inspected without fail, and only panels that passed those inspections were shipped from the factory. This makes it possible to completely prevent the occurrence of a very serious problem in terms of safety such as dropping of the panel due to insufficient strength of the panel end portion hanging on the beam, particularly when the panel is used as a roof or floor. Further, by automating the reinforcing bar detection process, inspection personnel are eliminated, and the detection can be performed while the panel is being conveyed, so that the efficiency is high and the economic effect of cost reduction is brought.

[Brief description of the drawings]

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of reinforcing bar detection by the eddy current displacement sensor according to the present invention.

FIG. 3 is a schematic plan view of an embodiment of the present invention.

FIG. 4 is an explanatory view of a conventional method for inspecting a cover thickness of a reinforcing reinforcing bar.

FIG. 5 is an explanatory diagram of another inspection method of a cover thickness of a conventional reinforcing bar.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 ALC panel 2 Reinforcing bar (reinforcing bar) 3 Main bar 4 Panel edge 5 ALC panel position detecting device 6 Guide roller 7 Eddy current displacement sensor 7a Head 8 Transport device 9 Sensor moving device 10 Sensor control amplifier 11 Control device Reference Signs List 12 Alarm buzzer 13 Reinforced reinforcing bar burying position detecting device 14 Steel plate 21 Rod pin hole 22 Reinforcing bar position detector 22a Magnet 22b Spring material H Cover thickness of secondary bar from panel surface G Gap L1 Distance between rod pin hole and center of secondary bar L2 Distance between rod pin hole and panel edge T Cover thickness of accessory bar from panel edge

Claims (2)

[Claims] An eddy current displacement sensor is brought close to a small face of the ALC panel while the ALC panel is being conveyed on the production line, and the amplitude or phase of the electric oscillation from the eddy current displacement sensor is adjusted. ALC by detecting change
A method for detecting the embedment position of a reinforcing bar of an ALC panel, comprising detecting a reinforcing bar buried in the panel. 2. An eddy current displacement sensor for detecting a reinforcing bar embedded in an ALC panel, an ALC panel position detecting device, and an ALC panel position detecting device.
A sensor moving device for bringing the eddy current displacement sensor closer to the ALC panel foreface when the position of the panel is detected, and an eddy current displacement sensor for bringing the eddy current displacement sensor closer to the ALC panel foreface Sensor head and AL
A burying position detecting apparatus for reinforcing bars of an ALC panel, comprising: a guide roller for keeping a distance from a front edge of a C panel constant.