JPH0438283B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method and apparatus for determining the overall axis, which is the turning center of the raw wood, when rotary cutting the raw wood using a veneer lace. Three or more arbitrary positions in the longitudinal direction of the log, including the vicinity of both ends, are used as calculation criteria for determining the overall axis of the log, and by rotating the gripping claws around the temporary center of the log as the rotation center. Based on the obtained calculation results, the amount of correction for the transport claws is calculated and the log is moved.

"Prior Art" Generally, when determining the turning center of a veneer lace on a log, the maximum inscribed circle common to both end faces of the log cut to an appropriate length is calculated, and
This is done by finding the center of this circle.

Specifically, at each plywood factory, a worker places a ruler on both ends of the wood, measures the lengths of the long and short axes that intersect at right angles, and then calculates the median line of each long and short axis and marks it in chalk. , the intersection of the median lines was found and used as the turning center.

Another method is to support the vicinity of both ends of the raw wood by a pair of cradle that can be raised and lowered and can move back and forth, and to project concentric circles onto both ends of the log from a pair of projectors placed above. Based on
Adjustments were made by vertical movement of the pedestal on the Y-axis of both butt ends 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 external shape of both butt ends of the raw wood. .

In addition, a pedestal on which the log is placed and a detector that detects the top surface of the log are placed opposite each other near both end faces of the log, and the two are brought close to each other from above and below at equal distances to sandwich the log. However, I was looking for a turning center.

"Problems to be solved by the invention" However, among the various methods described above,
In the first method, the major and minor axes of both end faces of the log are set independently by the operator's subjectivity, and when calculating the median line from the measured major and minor axes, errors inevitably occur and accuracy cannot be achieved. It is difficult to predict.

In addition, in the second method as well, the concentric circles projected onto both butt end faces are images from a projector separated by a certain distance, so the multiple concentric circles are in an expanded state, and the end face outline and arbitrary It becomes difficult to distinguish it from 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 positions near them as calculation criteria for determining the center of turning, so the bending or deformation of the raw wood in the longitudinal direction is determined by the operator's estimation each time. Therefore, the error in the turning center is further increased. Therefore, when rotary turning is actually performed using a veneer race, a large amount of veneer veneer with a narrow width that is less than the specified size is cut out.

"Means for Solving the Problems" In view of the above, the present invention detects cross-sectional contours at multiple locations in the longitudinal direction of the log by rotating the log gripped by gripping claws around a temporary center of rotation. Then, after correcting each transport claw located on both sides of the running body based on the coordinate value of the overall axis of the raw wood calculated from the detection results, the raw wood is gripped and exchanged from the gripping claw to the transport claw, and then this transport The claws are moved relative to the traveling body based on the amount of correction, and then the log is transported a fixed distance to the turning center of the veneer lace.

"Embodiments" Hereinafter, embodiments of the present invention will be described first from the configuration with reference to the accompanying drawings.

Machine frames 1 are vertically set up at arbitrary intervals on the left and right, and horizontal beams 2 are installed horizontally between the upper parts of the machine frames 1 to form a gate shape. A horizontal beam 3 is fixedly connected between the upper parts of each of the horizontal beams 3.

A pair of gripping fluid cylinders 4 are mounted facing each other between the left and right machine frames 1, and the tip of the piston rod 5 is fitted into and supported by a spindle 6 approximately at the center of the machine frame 1. It is attached to the rear end.

A gripping claw 9 for gripping the end face 8 of the log 7 is attached to the tip of the spindle 6, and a chain wheel 12 receives the rotation of a motor 10 installed in the machine frame 1 via a chain 11. It is slidable in the axial direction and is fitted integrally in the rotational direction. At this time, as shown in FIGS. 6 and 7, a large gear 13 is fitted into the driven spindle 6 located opposite to each other so as to be slidable in the axial direction and integrally with respect to the rotational direction. A small-diameter linking gear 14 is meshed with this large gear 13, and a small gear 15 fitted into the shaft of this linking gear 14 and a pinion 17 of a rotary encoder 16 attached to the machine frame 1 are meshed with each other. In addition, a log rotation angle detector 18 is arranged to measure the rotation angle of the log 7 at arbitrary angles.

On the other hand, a displacement detector 19 is installed on the cross beam 2 to detect an arbitrary cross-sectional contour of the log 7 in the longitudinal direction.
However, they are installed at multiple locations, in this example, at three locations at the center and at both ends.

That is, the vicinity of the base of the swinging arm 21 is pivotally fixed between a pair of side plates 20 attached to the side faces of the cross beam 2 in the direction in which the logs 7 are carried in, with a pin 22, and a displacement fluid cylinder is attached to the front part of the cross beam 2. 23 is pivoted, and the tip of the piston rod 24 is pivoted to the swinging arm 21, and the tip of the swinging arm 21 is constantly moved to the outer peripheral surface of the log 7 using the contact part of the pin 22 as a fulcrum by fluid movement. It is pressed into contact. Further, the semicircular measuring plate 25 fitted to the contact portion of the pin 22 of the swinging arm 21 and the pinion 27 of the encoder 26 attached to the side plate 20 are brought into mesh with each other,
The swing position of the swing arm 21 is detected.

In addition, the displacement detectors 19 located at both ends are connected to a pair of adjustment shafts 2 attached to the cross beam 2 so that the detection position can be moved freely according to the length of the log 7, as shown in the illustrated example.
In some cases, the end of the piston rod 30 of the adjusting fluid cylinder 29 attached to the cross beam 2 is connected to the side plate 20 by inserting the side plate 20 into the side plate 8 .

Next, using the left and right horizontal beams 3 as rails, a traveling body 32 with wheels 31 supported at its four corners is horizontally suspended parallel to the cross beams 2, so that it can freely reciprocate up to the veneer race 33.

Hanging bodies 35 are fitted on the left and right sides of the traveling body 32 so as to face each other on horizontal shafts 34 arranged parallel to the cross beam 2. The tips of the piston rods 37 of a pair of suspension fluid cylinders 36 are fixed in the same direction, and
Each hanging body 35 is movable along the horizontal axis 34.

Furthermore, a pair of vertical sliding shafts 38 are attached to both sides of opposing surfaces of each suspension body 35, and the tip of a piston rod 40 of a Y-axis correction fluid cylinder 39 is pivotally fixed to the back surface of each suspension body 35. is attached to an adjusting plate 41 fitted into the vertical sliding shaft 38, and the adjusting plate 41 is moved up and down in balance along the vertical sliding shaft 38, and the Y
A piston rod 40 is attached to the axis correction fluid cylinder 39.
An encoder 42 for detecting the amount of movement of the adjustment plate 41 is attached thereto, and a Y-axis correction device 43 for regulating the amount of descent of the adjustment plate 41 is provided.

In addition, a pair of horizontal sliding shafts 44 are attached to the upper and lower parts of the adjustment plate 41, and an X-axis correction fluid cylinder 45 is attached to the center thereof, and the tip of the piston rod 46 is connected to a pair of horizontal sliding shafts 44. The X
A piston rod 46 is attached to the axis correction fluid cylinder 45.
An encoder 48 for detecting the amount of movement of the conveyance claw 47 is attached thereto, and an X-axis correction device 49 for regulating the amount of advance and retreat of the transport claw 47 is provided.

In addition, the Y-axis correction fluid cylinder 39 is regulated from the upper limit position of the adjusting plate 41 to two stages: a first-stage lowering T for Y-axis correction, and a second-stage lowering L after gripping the raw wood 7. . Therefore, in order to regulate the position after the second stage lowering L to either the middle stage or the lower stage depending on the size of the diameter of the log 7, a circumscribed piston rod 50 is included that slides on the outer periphery of the piston rod 40 in the cylinder chamber. There is.

In addition, in order to restrict the second stage lowering L of the transport claw 47, a fluid cylinder (not shown) for the second stage lowering L is suspended in series on the piston rod 40 of the Y-axis correction fluid cylinder 39. , connects the rear end of the conveying claw 48 to the tip of the piston rod (not shown), and furthermore, is movable to mechanically restrict the first stage lowering T and second stage lowering L of the Y-axis correction fluid cylinder 39. It is also possible to provide a stop (not shown).

In addition, 51 in the figure is a chuck of the veneer lace 33.

"action" Next, the action will be explained.

First, when transporting the log 7 to the centering position,
The piston rod 5 of the gripping fluid cylinder 4 is retracted to retract the gripping claw 9 as shown in FIG. 3, and the piston rod 40 of the Y-axis correction fluid cylinder 39 is retracted as shown in FIG. let me,
The adjustment plate 41 is placed on standby at the upper limit position along the vertical sliding shaft 38, and the X-axis correction fluid cylinder 45
The piston rod 46 is extended, and the conveying claw 47 is placed on standby at the backward limit position along the horizontal sliding shaft 44.

In addition, after adjusting the positions of the swinging arms 21 at both ends using the adjustment fluid cylinder 29 according to the length of the logs 7 to be carried in, the piston rod 24 of the displacement fluid cylinder 23 is extended, and the swinging arms 21 pin 2
Retract to the upper limit position using the 2nd contact part as a fulcrum.

Next, the log 7 that has been tentatively centered is carried into the centering position, and the gripping fluid cylinder 4 is operated to align the tentative center of both end faces 8 with the center of the gripping claw 9, and the log 7 is gripped. do.

Furthermore, by operating the displacement fluid cylinder 23, each swinging arm 21, which had been retracted to the upper limit, is moved to the pin 2.
It is pressed against the outer peripheral surface of the log 7 in the longitudinal direction using the 2nd contact part as a fulcrum with a constant pressure.

When the drive of the motor 10 is transmitted to the chain wheel 12 through the chain 11, the spindle 6 is rotated, and the log 7 is rotated once around the temporary center. At this time, the amount of rotation of the log 7 is measured by the log rotation angle detector 18, and each arbitrary cross section near both ends and the center of the log 7 is measured as the amount of displacement from the line connecting both end faces of the log 7. Each amount is detected synchronously by the quantity detector 19.

That is, in the log rotation angle detector 18, the rotation angle of the spindle 6 on the driven side is sequentially detected by the rotary encoder 16 via the pinion 17, and on the other hand, in each displacement detector 19,
The radius and deviation angle from the rotation center axis for each arbitrary cross section are
The contact portion of the pin 22 is regarded as a fulcrum, and the amount of displacement is sequentially detected by the encoder 26 via the pinion 27 that meshes with the measurement plate 25.

Therefore, the electric signal of the arbitrary angle detected by the log rotation angle detector 18 and the electric signal of the displacement amount detected by the displacement amount detector 19 are extracted synchronously and Contours are detected. Each of these cross-sectional contours is input to a calculation device (not shown) and is appropriately calculated based on each data to obtain the coordinate value of the overall axis of the log 7. Furthermore, the deviations of the X-axis and Y-axis from this coordinate value and the temporary center, that is, the rotation center, are determined, and the X-axis correction device 4
9. Give instructions to the Y-axis correction device 43.

Next, based on FIG. 9, correction of each deviation will be specifically explained. If the rotation center O is the coordinate origin 0, 0, and the coordinate values of the overall axis G are GX, -GY, then the correction amount on the The claw 47 is the horizontal sliding shaft 44
The midpoint of the distance traveled from the backward limit to the forward limit,
In other words, the amount of movement is obtained by subtracting GX from the center position of the adjustment plate 41.

In addition, the correction amount on the Y axis is a predetermined lowering amount B of the adjusting plate 41, that is, the conveying claw 47 (for example, when the adjusting plate 41 waits at the upper limit position on the vertical sliding shaft 38, the lower end of the conveying claw 47 Therefore, the moving amount is obtained by subtracting -GY from the descending amount, which is the distance to the origin on the Y coordinate minus a slight margin for the radius of the chuck 51, and this is the first stage descending T.

Therefore, the coordinate value of the total body axis G is 0,0, that is,
If it is the same as the rotation center 0, the amount of movement on the X axis (the amount that the conveying claw 47 moves on the horizontal sliding shaft 44) is
The predetermined advance amount is A, and the correction amount on the Y axis is (the amount by which the adjustment plate 41 moves on the vertical sliding shaft 38)
becomes a predetermined amount of fall B.

The calculated correction amount is transmitted to the X-axis correction fluid cylinders 45 of the X-axis correction devices 49 located on the left and right, moves the conveyance claws 47 forward along the horizontal sliding shaft 44 on the left and right separately, and is transmitted to the encoder 48. Therefore, the amount of advance detected sequentially is fed back to the arithmetic unit to accurately control the amount of correction.

In synchronization with this, the correction amount is transmitted to the Y-axis correction fluid cylinders 39 of the Y-axis correction devices 43 located on the left and right, and the adjustment plate 41 (conveying claw 47) is moved to the vertical sliding shaft 3.
8, and the amount of descent successively detected by the encoder 42 is fed back to the arithmetic unit to accurately control the amount of correction.

Next, the pair of suspension fluid cylinders 36 are operated to cause the conveying claws 47 to bite into both end faces 8 of the log 7, and then the gripping claws 9 are removed from both end faces 8 of the log. After replacing the grip, operate the X-axis correction fluid cylinder 45 to move the conveying claw 47 to the horizontal sliding axis 4.
4, the piston rod 40 is slid to the forward limit position, the Y-axis correction fluid cylinder 39 is activated, and the piston portion of the piston rod 40 is moved to the tip of the rod portion of the circumscribed piston rod 50, where the second stage downward movement L is regulated in the cylinder chamber. Lower it until it touches the
The log 7 is moved in accordance with the correction.

At this time, the raw wood 4 is held in a relatively centered state by the pair of transport claws 47 on the geometric coordinates of both end faces 8 of the wood.

Therefore, the height of the axis gripped by the conveying claws 47 becomes the same as the turning center S of the chuck 51 of the veneer race 33, and then the traveling body 32 is moved to the horizontal beam 3.
The upper part is moved forward by a fixed distance C to align the overall axis G of the log 7 with the turning center S, and the grip of the log 7 is exchanged between the transport claw 47 and the chuck 51.

Note that the second stage lowering L of the transport claw 47 and the moving body 32
If the constant advance C is carried out at the same time, the time for supplying the raw wood 7 to the chuck 51 of the veneer lace 33 can be shortened.

In addition, in this embodiment, for convenience, the Y-axis correction device 43 has a Y-axis correction fluid cylinder 39 attached to the back surface of each suspension body 35, and the adjustment plate 41 is moved along the vertical sliding axis 38. Balance lifting and X-axis correction device 49
A fluid cylinder 45 for X-axis correction is attached to this adjustment plate 41.
is attached to control the balance of the conveyance claw 47 along the horizontal sliding shaft 44. However, the X-axis correction device 49 is attached to the back of each suspension member 35, and the Y-axis correction device 43 is attached to the adjustment plate 4.
It is also possible to change the installation to 1.

Furthermore, in this embodiment, the X
Although it is explained that the starting point of the correction amount on the axis is the backward limit and the end point is the forward limit, it is possible to change this end point again to the backward limit, or to change the starting point to the forward limit and the end point to the backward limit, etc. .

"Effects" As described above, according to the present invention, by rotating the raw wood gripped by the gripping claws around a temporary center of rotation, the cross-sectional contours of multiple locations in the longitudinal direction of the log are detected, and based on the detection results. After correcting each transport claw located on both sides of the running body based on the calculated coordinate values of the entire axis of the log, the log is gripped and exchanged from the gripping claw to the transport claw, and then the transport claw is adjusted to the correction amount. The log is then moved a certain distance to the center of turning of the veneer race.
For veneer veneers cut by veneer laces in which accurate turning centers are automatically obtained, compared to those determined by the various conventional methods described above,
The acquisition rate of continuous veneer veneer is improved. Also,
The amount of discontinuous veneer veneer discharged is reduced, and workability in subsequent steps can be improved.

In addition, the correction based on the coordinate value of the overall axis of the raw wood can be performed by a single transporting claw, and the movement of the raw wood based on the correction amount is regulated at the mechanical limit position of the transporting claw. This is not only effective in controlling heavy objects such as logs, but also reduces the time required.

[Brief explanation of drawings]

FIG. 1 is a plan view showing one embodiment of the present invention, and FIG.
The figure is a side view of Fig. 1, Fig. 3 is a partially cutaway front view of Fig. 1, Fig. 4 is a view taken along the line A-A of Fig. 3,
Figure 5 is a view taken along line B-B in Figure 4, Figure 6 is a front view of the log rotation angle detector, Figure 7 is a side view of Figure 6, and Figure 8 is a front view of the displacement detector. FIG. 9 is a schematic explanatory diagram of the operation. 1...Machine frame, 3...Horizontal beam, 6...Spindle, 7...
Log, 9...Gripping claw, 18...Log rotation angle detector, 1
9... Displacement amount detector, 21... Rocking arm, 32... Traveling body, 35... Hanging body, 41... Adjustment plate, 43... Y-axis correction device, 47... Transport claw, 49... X-axis correction device.

Claims (1)

[Claims] 1. By rotating the log gripped by the gripping claws around a temporary center, the cross-sectional contours of multiple locations in the longitudinal direction of the log are detected, and the entire log is calculated from the detection results. After correcting each conveyance claw located on both sides of the traveling body based on the coordinate value of the axis center, the log is gripped and exchanged from the gripping jaw to the conveyance jaw, and furthermore, the conveyance jaw is moved relative to the traveling body based on the correction amount. A method for centering logs that is characterized by moving them. 2. The method for centering logs according to claim 1, wherein the standby position of the transport claw before correction is the backward limit and the upward limit position with respect to the traveling body. 3. The method for centering logs according to claim 1, wherein the standby position before correction of the conveyance claw is at the forward limit and ascent limit position with respect to the traveling body. 4. The method for centering logs according to claim 1, wherein the movement position based on the correction of the transport claw relative to the traveling body is the backward limit and the lower limit position. 5. The method for centering logs according to claim 1, wherein the movement position based on the correction of the transport claw relative to the traveling body is the forward limit position and the downward limit position. 6 A gripping claw is attached to the tip of the spindle, which is arranged in a pair on the left and right and can move forward and backward in the horizontal direction, and a rotation angle detector is attached near the base end, while the spindle can move freely using the horizontal beam at the top of the machine frame as a guide. Transport claws, which are movable forward and backward by an X-axis correction device and can be raised and lowered by a Y-axis correction device, are suspended from both sides of a traveling body suspended horizontally, and furthermore, the logs are placed at arbitrary intervals in the longitudinal direction of the logs. A displacement detector is attached to the base end of each of the plurality of swinging arms and pivotally fixed, and the total body axis is calculated from each data of the rotation angle detector and the displacement detector. Based on the coordinate values of
A log centering device characterized by outputting a correction amount to an axis correction device and outputting a downward correction amount to a Y-axis correction device.