JPH0428504A - Iron piece detection method for log and its device - Google Patents

Abstract

PURPOSE:To eliminate the touble of malfunction caused by the external turbulence of earth magnetism by bringing a plurality of iron piece detection sensors divided into the blocks of approximately an integral submultiple of the length of a log alternately on its outer periphery in the length direction, moving the sensors in the length direction almost per one rotation of the log and having the remaining iron pieces on the remaining undetected sites detect further. CONSTITUTION:Iron piece detection sensors 2a and 2b, divided into a plurality of blocks of an integral submultiple of its length and divided into two pieces of blocks of almost one-quarter of log 1, are mounted on the ends of movable parallel links 4a and 4b movable up and down through oscillating mechanisms 7a and 7b on the log 1. Also, a transversing mechanism 6 consisting of an air pressure cylinder 6a, a side rail 6b and the like is mounted on a bearing body 5 in a manner of being able to make movable parallel links 4a and 4b transverse approximately by an integral submultiple of its length.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the use of raw wood provided for the cutting process of veneer veneers, etc., to the outer periphery of the raw wood for use in underwater wood storage, etc., or for preventing cracking. Detects residual iron pieces, etc. that have been forgotten to be removed from anchors that have been driven in, during the transportation process before the cutting process.
This invention relates to a method for detecting iron pieces in logs and improvements to the device.

[Conventional technology]

This type of iron piece detection method and apparatus and iron piece detection sensor, which are conventional techniques, are designed to cover the whole log in a magnetic field created by an iron piece detection sensor such as a loop coil during the process of unloading logs using a conveyor such as a live roller. It is theoretically well known to those skilled in the art that residual iron pieces, etc. that have been forgotten to be removed near the outer periphery of the log can be electromagnetically detected by passing the log through the log.

[Problem to be solved by the invention]

However, this type of iron piece detection method and apparatus and iron piece detection sensor which are the above-mentioned prior art are based on an electromagnetic iron piece detection device made of an iron piece detection sensor such as a loop coil that is moved vertically across a conveyor for transporting logs. Therefore, iron piece detection sensors such as large loop coils, which are made to allow the free passage of large logs with a diameter of 1 m or more, are used to anchor the logs and prevent them from cracking. However, it is difficult to detect small residual iron pieces with a diameter of several meters to around 10 meters, and in practice the detection method is indirect from an extremely long distance. There were many unresolved problems, such as various problems with display, etc., and it remained within the scope of a merely theoretical detection technique and could hardly be put to practical use. Furthermore, as prior art, a method and apparatus for detecting iron pieces of logs disclosed in Japanese Patent Application Laid-Open No. 2-122901, which is an earlier invention of the present applicant, and a method using an iron piece detection sensor used in the method and apparatus are also disclosed in the longitudinal direction of the logs. It requires complicated and expensive equipment to arrange a large number of iron piece detection sensors in a line to cover the entire area of the log, and to switch individual control circuits according to the arrangement. If there is a large unevenness, the iron piece detection sensor will shake violently, causing disturbance due to the earth's magnetic field, which can cause malfunctions, which is a serious problem.

[Means to solve the problem]

The present invention improves the problems of the prior art and the difficulties of the prior art. That is, the iron piece detection method of the present invention includes supporting the log horizontally and rotating it in the circumferential direction, and A plurality of iron piece detection sensors divided into blocks each approximately an integer fraction of the length of the outer periphery are brought into contact with every other block in the length direction to detect residual iron pieces, and the iron piece detection sensor is connected to the raw wood. The iron piece is moved in the length and width directions approximately every rotation of the iron piece, thereby further detecting the remaining iron piece in the undetected area.

Further, the iron piece detection device of the present invention includes a drive mechanism that horizontally supports the raw wood at a detection position and rotates it in the circumferential direction, and a drive mechanism that supports the raw wood horizontally at a detection position and rotates the raw wood in the circumferential direction, A plurality of iron piece detection sensors are divided into blocks of approximately one integer fraction of the length, and the iron piece detection sensors are divided into blocks of approximately one integer of the length of the raw wood.
The apparatus includes a traversing mechanism attached to a sliding parallel link supporting body that supports the iron piece detection sensor so as to be able to traverse approximately one integer of its length each time it rotates. A neck capturing mechanism is attached to a sliding parallel link that supports the iron piece detection sensor so as to be able to swing up and down in the length direction, and wheels and a buffer mechanism are attached to both sides of the iron piece detection sensor, Further, the buffer mechanism of the device is composed of a hydraulic cylinder equipped with a pneumatic-hydraulic converter, a hydraulic check valve, and a hydraulic squeezing valve.

[For production]

A means for electromagnetically detecting iron pieces that have been left behind near the outer periphery of a log is to generate an electromotive voltage in the electromagnetic circuit of a detection coil by moving or rotating the log. Being able to detect the presence of residual iron pieces is
It has been theoretically known for a long time. However, iron pieces remaining near the outer periphery of logs are generally small, ranging from a few layers to around 10 meters in diameter, so they must be detected from close range by directly contacting the electromagnetic circuit of a detection coil to the outer periphery of the log. The current situation is that it cannot be put to practical use. Furthermore, if the electromagnetic circuit of the detection coil is brought into direct contact with the outer periphery of the log, the movement or rotation of the log will cause the electromagnetic circuit of the contact coil to oscillate, resulting in significant disturbance due to the geomagnetic field. In addition to being affected by As in the case of the earth's magnetism, it is difficult to put it to practical use because it is affected by disturbances caused by the earth's magnetic field. Therefore, the present invention is an attempt similar to the prior art in order to eliminate the influence of strong geomagnetic force and the influence of mutual induction from the electromagnetic circuit of the detection coil. As illustrated in FIGS. 4 to 6, the iron piece detection sensor includes a detection magnet 101 and a dummy magnet 102 on both sides of a band iron 100.
The magnets 101 and 1 are fixed symmetrically, and the magnets 101, 1
02 each has an iron core 103 for detection and a coil 104.
and a coil 106 containing a dummy iron core 105 are symmetrically stacked and fixed to form a pair of upper and lower unit iron piece detection units 107.
By further arranging a large number of iron piece detection sensors +j--28, 2b for each block on the iron band 100, the iron piece detection sensors 2a, 2b detect logs that are not perfectly round. Even if it swings slowly in the vertical direction as it rotates, disturbances due to the influence of the earth's magnetic field can be detected by the detection coil 104 and the dummy coil, as shown in FIG. 106 generated voltage E1.
By differentially connecting the differential voltage E3 of E2 so that it can be detected, it has become possible to eliminate disturbances in the earth's magnetic field caused by slow fluctuations. However, there were large irregularities such as bumps and depressions on the outer periphery of the log, and it was not possible to eliminate disturbances caused by the earth's magnetic field when the iron piece detection sensors 2a and 2b were suddenly swung vertically. However, in the present invention, a small amount of raw wood is placed on both sides of the iron piece detection sensors 2a and 2b in order to convert the sudden vertical movement into a slow movement and substantially eliminate the disturbance. The wheels are raised from the outer periphery to eliminate shocking rocking caused by sliding, and the shock absorbing mechanism of the pneumatic conversion hydraulic circuit is used to slow down the rapid vertical rocking due to the fluid resistance of incompressible liquid. It was installed. Further, the disturbance caused by the mutual induction of the electromagnetic circuit of the detection coil 104 causes the iron piece detection sensors 2a, 2b to be approximately an integer fraction of the length of the log.
The log is divided into multiple blocks, and the remaining iron pieces are detected only directly under the block by contacting every other block in the length direction of the log. By moving and further detecting the remaining iron pieces in the undetected areas, the mutual spacing between the plurality of iron piece detection sensors 2a and 2b becomes wider,
This is designed to eliminate substantial disturbances due to mutual induction between blocks.

〔Example〕

Figures 1 and 2 show an example of the raw wood iron piece detection device of the present invention, in which a raw wood 1 is first transported horizontally to a detection position by a live roller 14, and a drive that rotates the raw wood 1 in the circumferential direction is used. The conveyor 15a is moved from above the live roller 14 by a lifting mechanism 15b such as a hydraulic cylinder mounted on the conveyor 15a of the mechanism 15.
It is scooped up and rotated by a variable speed motor 15C at a predetermined speed, for example at a speed of about 24 m/-. On the other hand, above the log 1, the log is divided into a plurality of blocks each approximately an integer fraction of its length, for example, as shown in the figure, it is divided into two blocks each approximately a quarter of the length of the log 1. The divided iron piece detection sensors 2a, 2b are attached to the ends of vertically movable sliding parallel links 4a, 4b via swing mechanisms 78, 7b. In addition, the iron piece detection sensors 2a, 2
On both sides of b are wheels 8a that lift it slightly from the outer periphery of log 1.

8b, and buffer mechanisms 9a and 9 that slow down its rapid swinging.
b is attached. Furthermore, the sliding parallel link 4a
, 4b, a support 5 is attached to the machine frame 18, and the support 5 has chenographs 17a, 17b wrapped around hydraulic cylinders 16a, 16b so as to be able to freely move vertically as a whole. A traversing mechanism 6 consisting of a pneumatic cylinder 6a, a slide rail 6b, etc. allows the sliding parallel links 4a and 4b to traverse approximately one integer fraction of the length of the log 1 for each approximately one revolution of the log 1.
is installed. In addition, the sliding parallel links 4a, 4b
Pneumatic cylinders 19a and 19b installed above the
acts to maintain the overall weight balance including heavy objects such as the iron piece detection sensors 2a, 2b attached to the tips of the sliding parallel links 4a, 4b, and is attached on both sides of the iron piece detection sensors 2a, 2b. Wheels Ba,
A magnetic system detects the point in time when Bb contacts the outer periphery of the log 1 by its vertical movement, and thereby automatically controls the vertical movement of the support body 5, which has the chenos 17a, 17b wrapped around the hydraulic cylinders 16a, 16b. It is equipped with a control device such as a sensor. Next, on both sides of the iron piece detection sensors 2a and 2b, buffer mechanisms 9a and 9b of a pneumatic conversion hydraulic circuit as illustrated in FIG. The buffer mechanisms 9a and 9b are equipped with the iron piece detection sensors 2a and 2 because there are large irregularities such as bumps and depressions on the outer periphery of the log 1.
In order to eliminate the disturbance caused by the earth's magnetic field when b suddenly oscillates vertically, the sudden oscillation phenomenon is treated with an incompressible fluid,
For example, compressible gas such as compressed air, which is supplied at a predetermined pressure, is converted into a slow rocking phenomenon by the fluid resistance of liquid such as oil, using the pneumatic-hydraulic converter 10. Hydraulic cylinders 11a, 1
1b, hydraulic check valves 12a, 12b, hydraulic squeezing valve 13a,
A pneumatic conversion hydraulic circuit connected in parallel to the hydraulic cylinder 13b converts the rapid shaking phenomenon acting on the hydraulic cylinders 11a and 11b into a slow shaking phenomenon that does not cause disturbance due to the earth's magnetic field, thereby extending the response time. The system is designed to handle the following situations.

[Effects of the Invention] As explained above, the present invention provides a plurality of blocks divided into blocks each approximately an integer fraction of the length of the raw wood while rotating the raw wood in the circumferential direction during the transportation process of the raw wood. The iron piece detection sensors are brought into contact with every other iron piece in the length direction to detect the remaining iron pieces, and the iron piece detection sensors are moved in the length direction approximately every rotation of the log to detect the remaining undetected parts. Since the remaining iron pieces are further detected and the iron piece detection sensor is equipped with an incompressible fluid resistance buffering mechanism, this kind of iron piece detection method and device, which are conventional techniques, have caused problems. This overcomes all the problems of geomagnetism and mutual guidance, and according to the present invention, the diameter number M to 10#EII, which is driven into the log to stop it and prevent it from cracking.
+ Small residual iron pieces on the front and back can be detected, not only those exposed on the outer surface of the raw wood, but also those that have been driven into the center by several tens of anns and are broken, so they can be used for cutting tools in the later stages of the process. Not only was it extremely beneficial in terms of preventing breakage and thereby improving efficiency and economics, but it also improved the geomagnetic field, which was still caused by the prior art, by detecting iron pieces in logs that had been greatly deformed due to bumps and depressions. Malfunctions caused by external disturbances have been virtually eliminated, and the implementation effects in terms of process control are also extremely significant.

[Brief explanation of the drawing]

Fig. 1 is a front view of the device, Fig. 2 is a plan view, Fig. 3 is a block diagram of the buffer mechanism, Fig. 4 is a front view of the iron piece detection sensor, Fig. 5 is a plan view, and Fig. 6 is a plan view. Similarly, FIG. 7 is a side view and a circuit diagram. 1... Log, 2a, 2b... Iron piece detection sensor, 3
... Drive mechanism, 4a, 4b... Sliding parallel link, 5
...Support, 6...Transverse mechanism, 7a, 7b...Neck capture mechanism, 3a, 3b...Wheel, 9a, 9b...Buffer mechanism, 10...Pneumatic hydraulic converter, 118.11b・
...Hydraulic cylinders 12a, 12b...Hydraulic check valves, 13a, 13b...Hydraulic throttle valves.

Claims (1)

[Claims] 1. The log (1) is supported horizontally and rotated in the circumferential direction, and the outer circumference of the log (1) is divided into blocks each approximately an integer fraction of its length. A plurality of iron piece detection sensors (2a, 2b) are brought into contact with each other in the length direction to detect residual iron pieces, and the iron piece detection sensors (2a, 2b) are rotated approximately once around the log (1). A method for detecting iron pieces in logs, characterized in that the remaining iron pieces in undetected areas are further detected by moving in the length direction of each piece of wood. 2. A drive mechanism (3) that horizontally supports the raw wood (1) at a detection position and rotates it in the circumferential direction; A plurality of iron piece detection sensors (2a, 2b) divided into blocks each approximately an integer fraction of the length of the log (1), and the iron piece detection sensor (
2a, 2b) are freely traversed by approximately an integer fraction of the length of the raw wood (1) approximately every rotation of the log (1), and the iron piece detection sensor (2
A log iron piece detection device characterized in that a traversing mechanism (6) is attached to a support body (5) of a vibrating parallel link (4a, 4b) that supports the vibrating parallel links (4a, 2b). 3. The iron piece detection sensors (2a, 2b) can be freely swung up and down in the length direction of the log (1).
, 2b), and wheels (8a, 8b) and buffer mechanisms ( 9a, 9b), the log iron piece detection device according to claim 2. 4. The buffer mechanism (9a, 9b) is a pneumatic hydraulic converter (10)
Hydraulic cylinders (11a, 11b) equipped with hydraulic check valves (12a, 12b) and hydraulic squeezing valves (13a, 13b)
) The raw wood iron piece detection device according to claim 3, comprising: