JPS61217207A - Method and device for centering log - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention provides
The present invention relates to a method and apparatus for determining the overall axis of the turning center of a log, and in particular, over the longitudinal direction of the log.
Three or more arbitrary positions, including the areas near both ends, are used as calculation standards to determine the coordinate values of the entire body axis of the log, and the calculation results obtained by rotating the gripping claws around the temporary center of the log as the rotation center. Based on this, calculate the forward correction amount on the y-axis and the downward correction amount on the y-axis of the gripping claw located at the backward limit,
It is used to move logs.

``Prior art'' Generally, in order to determine the turning center of a veneer lace on raw wood, the maximum inscribed circle common to the side end faces of the raw wood cut to an appropriate length is calculated, and the center of this circle is found. It is done by

Specifically, at each plywood factory, workers place property rights on both grain edges of raw wood, measure the lengths of the major and minor axes that intersect at right angles, and then calculate the median line of each major and minor axis and mark it in chalk. The center of turning was determined by finding the intersection of the median lines.

Another method is to support the area near the end of the log by a pair of supports that can move up and down and back and forth, and to project concentric circles from a pair of projectors placed above onto the end of the side of the log. Based on this, adjustments were made by vertical movement of the pedestal on the y-axis of both grain end faces of the raw wood, and back and forth movement of the pedestal on the X-axis, and the turning center was set at the center of an arbitrary concentric circle inscribed in the outer shape of the side wood end face .

Furthermore, a method in which a pedestal on which the log is placed and a detector that detects the top surface of the log are placed facing each other near both ends of the grain of the log, and the two are brought close to each other from above and below at equal distances to sandwich the log, can also be used. I was looking for a turning center.

However, among the various methods described above, the first method independently sets the major and minor axes of the end face of the log depending on the operator's subjectivity, and when calculating the median line from the measured major and minor axes, it is necessary to Errors occur and it is difficult to ensure accuracy. Even in the first and second methods, the concentric circles projected on both wood grain end faces are images from projectors separated by a certain distance, so it is difficult to ensure accuracy. The concentric circles are in a widened state, making it difficult for the operator to distinguish between the end face contour and the arbitrary concentric circles. Furthermore, in the third method, even if the amount of rise of the pedestal and the amount of fall of the detector are controlled to be equidistant, the cross section of each log is irregular, so the clamping state will be inaccurate.

In addition, each of the above methods uses both ends of the raw wood or the positions near them as calculation criteria for determining the center of turning, so bending or deformation in the longitudinal direction of the raw wood depends on the operator's intuition each time. Therefore, the error in the turning center is further increased. Therefore, when a veneer lace is actually rotary cut, a large amount of veneer veneer with a narrow width that is less than the specified size is cut out.

``Problems to be Solved by the Invention'' In view of the upward slope, the present invention is designed to rotate the temporary center of the raw material as a rotation center by means of a gripping claw that waits at the retraction limit at the centering position of the raw material, and to extend in the longitudinal direction. After detecting the cross-sectional contours at multiple locations and calculating the coordinate values of the overall body axis, the correction amount on the X axis based on these coordinate values is
The amount of correction on the axis is performed by the downward movement of the transport claws that grip and replace the raw wood from the gripping claws, and then the raw wood is transported a fixed distance to the turning center of the veneer race.

"Example" Embodiments of the present invention will be described below with reference to the accompanying drawings.

A plurality of pairs of machine frames 1 are erected in the vertical direction at arbitrary intervals left and right, and cross beams 2 are horizontally suspended between the upper parts of the machine frames 1 to form a gate shape. Horizontal beams 3 are fixed and connected between the upper parts of the machine frames l.

Between each machine frame 1 on both the left and right sides, there is a pair of guide shafts 4 facing each other.
are respectively attached, and the perforated portions at both ends of the upper part of the bearing box 5 are fitted into the pair of guide shafts 4 to support the bearing box 5.

A gripping fluid cylinder 7 is attached to the rear part of the support body 6 extending from the lower end of the bearing box 5, and the tip of the piston rod 8 is fitted into and supported by the substantially central part of the bearing box 5. It is attached to the rear end of 9.

At the tip of this spindle 9, there is a butt end surface 11 of the log 10.
A gripping claw 12 is attached near the center of the gripping claw 12 for gripping the support 6, and a motor 13 installed at the bottom of the support 6 rotates
A chain wheel 15 that is passively driven via a chain 714 is slidable in the axial direction and is integrally fitted in the rotating direction. At this time, as shown in FIGS. 6 and 7, a large gear 16 is mounted on the driven side spindle 9, which is fitted and supported by the other bearing box 5 located opposite to each other, and which is slidable in the axial direction. A small-diameter linking gear 17 is fitted into the large gear 16 integrally with respect to the rotating direction, and a small gear 18 fitted onto the shaft of the linking gear 17 is attached to the support 6. The binions 20 of the attached rotary encoder 19 are meshed,
A log rotation angle detector 21 is arranged to measure the rotation angle of the log 10 at each arbitrary angle.

Further, an X-axis correction fluid cylinder 22 is attached to the center of the bearing box 5, and the tip of its piston rod 23 is attached to one of the machine frames 1, and is arranged parallel to the guide shaft 4. The pinion 26 of the encoder 25 attached to the support body 6 is meshed with the rack 24, and the limit switch 2
7, an X-axis correction device 28 is arranged to reset the encoder 25 and regulate the amount of movement of the bearing box 5 from the backward limit.

On the other hand, the cross beam 2 is provided with displacement detectors 29 at a plurality of locations for detecting arbitrary cross-sectional contours in the longitudinal direction of the log 10.
In this embodiment, three locations are provided, one in the center and one at both ends.

That is, between a pair of side plates 30 attached to the side surfaces of the cross beam 2 in the direction in which the logs 10 are carried in, the vicinity of the base of the dogleg-shaped swinging arm 31 is pivoted by a pin 32, and the rear part of the swinging arm 31 is supported by a pin 32. It is pivoted to the displacement fluid cylinder 33, and the tip of the piston rod 34 is pivoted to the upper part of the pair of side plates 30, and the tip of the swinging arm 31 is constantly moved by fluid movement, using the contact part of the bin 32 as a fulcrum. It is brought into pressure contact with the outer peripheral surface of 10. Furthermore, the semicircular measuring plate 35 fitted to the contact portion of the swinging arm 31 with the bin 32 and the pinion 37 of the encoder 36 attached to the side plate 30 are brought into mesh with each other, and the swinging displacement of the swinging arm 31 is adjusted. Detecting the amount.

In addition, the displacement amount detectors 29 located at both ends are arranged so that their detection positions can be moved freely according to the length of the log 10, as shown in the illustrated example.
In some cases, the side plate 30 is fitted onto a pair of adjustment shafts 38 attached to the cross beam 2, and the tip of the piston rod 40 of the adjustment fluid cylinder 39 attached to the cross beam 2 is connected to the side plate 30.

Next, using the left and right horizontal beams 3 as rails, a traveling body 42 with wheels 41 supported at its four corners is horizontally suspended parallel to the cross beam 2, so that it can freely reciprocate up to the veneer race.

On both left and right sides of the running body 42, suspension supports are fitted into horizontal shafts 43 arranged parallel to the crossbeam 2 so as to face each other, and each suspension support 44 is provided with an opposite side at the bottom of the running body 42. The ends of piston rods 46 of a pair of fluid cylinders 45 for suspension bodies are attached to each other, and each suspension body 44 is movable along a horizontal axis 43.

Furthermore, a transport claw 48 is fitted into a pair of guide shafts 47 hanging from the lower end of each suspension member 44, and the rear end of the transport claw 48 is attached to the suspension member 44 in the opposite direction. An encoder 51 is attached to the piston rod 50 of the X-axis correction fluid cylinder 49 and attached to the side of the suspension body 44.
An X-axis correcting device 54 is provided that meshes the pinion 52 with a rack 53 attached to the side of the transport claw 48 and regulates the amount of descent of the transport claw 48.

and the second stage descending after grasping the log 10. Therefore, the position after descending from the second stage is regulated to either the middle stage or the lower stage depending on the diameter of the log. There is.

In order to restrict the two-stage descent of the transport claw 48, a fluid cylinder (not shown) for lowering the second stage is further suspended in series on the piston rod 50 of the X-axis correction fluid cylinder 49. The rear end of the conveyance claw 48 is connected to the tip of the piston rod (not shown), and the first stage downward movement T and second stage downward movement of the X-axis correction fluid cylinder 49 is mechanically restricted. It is also possible to provide a movable stop (not shown).

In addition, numeral 56 in the figure is a chuck made of veneer lace.

1 action” Next, the action will be explained.

First, when carrying the log 10 to the centering position, the piston rod 8 of the gripping fluid cylinder 7 is contracted, and the first
As shown in the figure, the gripping claw 12 is retracted, and as shown in FIG. At the same time, the positions of the swinging arms 31 at both ends are adjusted by the adjustment fluid cylinder 39 according to the length of the log 10, and then the piston rod 34 of the displacement fluid cylinder 33 is extended, and the swinging arm 31 is moved to the pin 32. Retract to the upper limit position using the contact part as a fulcrum.

Next, the raw wood 10 that has been temporarily centered according to the method described above is carried to the centering position, and the pair of gripping fluid cylinders 7 is operated to align the temporary center of the side grain end face 11 and the center of the gripping claw 12. Match them and grasp the log 10.

Furthermore, the displacement fluid cylinder 33 is activated to press the swinging arms 31, which had been retracted to the upper limit, against the longitudinal outer circumferential surface of the log 10 using the contact portion of the bin 32 as a fulcrum with a constant pressure.

When the drive of the motor 13 is transmitted to the cheno wheel 15 via the chenno 14, the spindle 9 is rotated, and the log 10 is rotated once around the temporary center. At this time, the amount of rotation of the log 10 is determined by the log rotation angle detector 21, and each arbitrary cross section near both ends and the center of the log 10 is determined by the displacement from the line connecting the tentative centers of the side end faces 11 of the log 10. As the amount, each displacement amount detector 29
In other words, in the log rotation angle detector 21, the rotation angle of the spindle 9 on the driven side is sequentially detected by the rotary encoder 19 via the pinion 20. In the detector 29, the radius and deflection angle from the rotation center axis for each arbitrary cross section are taken as the amount of displacement of the swinging arm 31 that swings around the contact portion of the bottle 32 as a fulcrum, and this amount of displacement is determined by the measurement plate. Encoder 3 via a pinion 37 meshing with 35
6 has been successively detected.

Therefore, the electric signal of the arbitrary angle detected by the log rotation angle detector 21 and the electric signal of the displacement amount detected by the displacement amount detector 29 are taken out synchronously, and a plurality of cross-sectional contours are detected. . Each of these cross-sectional contours is calculated by the calculation unit (
(not shown) and is appropriately calculated based on each data to obtain the coordinate values of the entire body axis of the log 10. Furthermore, the y-axis and the deviation of the y-axis from this coordinate value and the temporary center, that is, the rotation center, are determined, and the X-axis correction device 28,
Each instruction is given to the axis correction device 54.

Next, based on FIG. 10, correction of each deviation will be specifically explained. Suppose that the rotation center 0 is the coordinate origin (0, 0), and the coordinate value of the total body axis G is (Gx).

-Gy), then the correction amount on the y-axis is the predetermined advance amount A of the bearing box 5, for example, the advance amount of the transport claw 48 waiting at the upper limit position to the branch perpendicular line, minus (Gx). Become. In addition, the correction amount on the y-axis is determined by subtracting the radius α of the chuck 56 from the predetermined lowering amount B of the transport claw 48, for example, the distance from the lower end of the transport claw 48 waiting at the upper limit position to the y-coordinate (0). It is the amount of descent, and from now on (-Gy)
The first stage descending T is obtained by subtracting .

Therefore, if the coordinate values of the overall axis G are (,0,0), that is, the same as the rotation center O, the amount of movement of the bearing box 5 on the y-axis is the predetermined advance amount A, and the amount of movement on the y-axis is Transport claw 4
The first stage lowering T of 8 becomes a predetermined lowering amount B.

The calculated correction amount is first transmitted to the X-axis correction fluid cylinders 22 of the X-axis correction devices 28 located on the left and right, moves the bearing box 5 forward individually along the guide shaft 4, and is finally transmitted by the encoder 25. Next, the detected amount of advance is returned to the calculation/device to accurately control the amount of correction.

Next, the correction amount is transmitted to the X-axis correction fluid cylinders 49 of the X-axis correction device 54 located on the left and right, and the conveying claws 48 are lowered along the guide shaft 47, and the lowering amounts sequentially detected by the encoder 51 are transmitted. The amount of correction is accurately controlled by returning it to the arithmetic unit.

After the correction is completed, the pair of suspension fluid cylinders 45 are operated to cause the conveyance claws 48 to bite into the side end faces 11 of the logs 10, and then the grip claws 12 are removed from the side end faces 11. At this time, the raw wood 10 is held in a relatively centered state by the pair of transport claws 48 on the geometric coordinates of the side end face 11, and under this state, the X-axis correction fluid cylinder 49 is activated, and the second step is lowered in the cylinder chamber until the second stage descending is restricted and the piston portion of the piston 50 comes into contact with the tip of the rod portion of the circumscribed piston rod 55.

Therefore, the height of the axis gripped by the conveying jaws 48 becomes the same as the turning center S of the chuck 56 of the veneer race, and after that, the traveling body 42 is advanced by a fixed distance C on the horizontal beam 3, and the raw wood is The overall axis G of the log 10 and the turning center S are made to coincide with each other, and the log 10 is gripped and converted by the conveying claws 48 and the chuck 56.

Incidentally, if the second stage lowering of the transport claw 48 and the forward movement of the traveling body 42 by a fixed distance C are carried out at the same time, the time for supplying the logs 10 to the veneer race can be shortened.

"Effects of the Invention" As described above, according to the present invention, the log is rotated about the temporary center by the gripping claws waiting at the retraction limit, and the cross-sectional contours at multiple locations in the longitudinal direction are detected. , calculate the coordinate values of the overall axis of the log, and based on these coordinate values, first move the gripping claws forward to perform correction on the X axis,
Next, after the raw wood is gripped and exchanged from the gripping jaws to the conveying jaws, the conveying jaws are lowered to perform correction on the X axis, so that an accurate turning center can be obtained, and in the case of veneer veneer cut by the veneer race, The yield rate of continuous veneer veneers is improved compared to those obtained by the various conventional methods described above. In addition, the amount of discontinuous veneer veneer discharged is reduced, and workability in subsequent steps can be improved.

In particular, during correction, the bearing box is constantly regulated from moving forward by subtracting the correction amount on the X axis from the predetermined moving amount;
The conveying claw is constantly regulated to descend by subtracting the correction amount on the X axis from the predetermined descending amount, and both are controlled in one direction, resulting in a simple control method and mechanism.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing an embodiment of the present invention, Fig. 2 is a partially cutaway front view of the same, Fig. 3 is a front view of the X-axis correction device, Fig. 4 is a plan view of the same, Figure 5 is a side view of the same, Figure 6 is a front view of the log rotation angle detector, Figure 7 is a side view of the same, Figure 8 is a front view of the displacement detector, and Figure 9 is a front view of the X-axis correction device. The front view and FIG. 10 are schematic illustrations. 1. Machine frame, 5. Bearing box, 9. Spindle, 10.
... Log, 12. Gripping claw, 2]... Log rotation angle detector, 28. X-axis correction device, 29.. Displacement amount detector, 31.
- Swinging arm, 42... Traveling body, 48... Conveyance claw, 54...
・X-axis correction device, patent applicant: Taihei Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. The original is rotated around a temporary center by a gripping claw waiting at the retraction limit, and the cross-sectional contours at multiple locations in the longitudinal direction are detected, thereby determining the overall axis of the original. The coordinate values are calculated, and based on these coordinate values, the gripping claws are first moved forward to make corrections on the x-axis, and then the log is gripped and exchanged from the gripping claws to the transporting claws, and then the transporting claws are lowered and corrected on the y-axis. A method for centering logs, which is characterized by making corrections. 2. A pair of bearing boxes, which are horizontally movable between vertically erected machine frames using an x-axis correction device, have gripping claws attached to their tips and a rotation angle detector. The spindles are slidably inserted into each, and the horizontal beams at the top of the machine frame are used as guides to move the spindles onto the horizontally suspended traveling body.
Transport claws that can be raised and lowered by a y-axis correction device are suspended from both sides, and a displacement detector is installed at the base end of each swinging arm, which is arranged at arbitrary intervals in the longitudinal direction of the log. The forward correction amount of the bearing box is transferred to the x-axis correction device based on the coordinate value of the overall body axis calculated from each data of the rotation angle detector and the displacement amount detector. A log centering device characterized in that a downward correction amount of a claw is outputted to a y-axis correction device.