JPH0420003Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This invention is a gripping tool used in a device for determining the chuck center, which is the center of rotation of the raw wood, when rotary cutting the raw wood with a veneer lace. It is related to.

``Prior art'' Generally, to determine the chuck center of a log, the maximum inscribed circle common to both end faces of the log cut to an appropriate length is calculated, and the center of this circle is determined. It is being done.

Specifically, the vicinity of both ends of the log are supported by a pair of V-shaped pedestals that can be moved up and down and back and forth, and light is projected onto the end surface of the log from a pair of projectors placed above. Based on the concentric circles, the pedestal moves up and down on the Y-axis of both end faces of the raw wood.
On the X-axis, centering is performed by adjusting the back and forth movement of the pedestal, and then a pair of conveyor claws grips both ends of the raw wood and conveys it parallel or oscillatingly to the chuck center of the veneer lace. Ta.

However, the maximum inscribed circle is artificially determined based on the concentric circles projected onto the irregularly shaped butt end surface, and the core of the log is artificially determined by taking into account the curvature that exists in the longitudinal direction of the log. This lacks accuracy, and if you actually perform rotary cutting with veneer lace, you will end up cutting out a large amount of narrow veneer veneer that is less than the specified size.

For this purpose, we have eliminated the above-mentioned manual work, and in recent years, we have detected arbitrary cross-sections at multiple locations in the longitudinal direction of the log while holding both end faces of the log and rotating them. Based on each detected data, we have been able to determine the maximum right cylinder of the log. A method of obtaining the axial center is adopted, and the position of the log after calculation is corrected as appropriate for centering, and as described above, after gripping the pair of conveyor claws on both end faces of the wood, the log is released from its grip. This improves the centering accuracy and allows the veneer lace to be conveyed in parallel or in an oscillating manner to the chuck center.

Therefore, the gripping claws that clamp the log and move it at least once, and the conveyance claws that transport the log in parallel or in an oscillating manner, are both located on both end faces of the log, so the gripping claws are held so that they do not interfere with each other. It is not possible to make the nail small in diameter.

However, when the central part of both end faces of a log is held and rotated with small-diameter gripping claws, a large-diameter log, a log with irregularly shaped both end faces, and cracks, especially near the core, can occur on the end faces. For logs with weak parts, the rotation torque required for the log cannot be resisted, and the wood structure in the gripping area is destroyed, and the log becomes unable to rotate due to the gripping claws, making it difficult to perform this kind of centering work. It was considered impossible.

``Problems to be solved by the invention'' In view of the above, the present invention is designed to avoid mutual interference with the conveying claws that are synchronously interposed on both end faces of the raw wood, and has a simple structure. The present invention provides a gripping tool for rotating logs that can expand the gripping area on both wood end faces and resist rotational torque.

"Embodiments" Hereinafter, embodiments of the present invention will be described based on the accompanying drawings.

A plurality of claws 5 are planted on the surface 2 of the disc-shaped base 1, that is, on the side facing both end faces 4 of the log 3, and at arbitrary positions eccentric from the center K of the base 1. , into which the shaft portion of the spindle 6 is fitted from the back side, forming a gripping tool 7 for rotating logs.

On the other hand, as shown in FIGS. 3 and 4, a pair of left and right rails 9 are laid on the machine frame 8 above the centering position of the log 3, and on these rails 9 are mounted wheels supported at the four corners. 10, a running body 11 is installed which can run freely in parallel to a check center of a veneer lace (not shown). In addition, this running body 1
A pair of support shafts 12 are arranged on the left and right sides of the log 1 , and a transport claw 13 that is slidable in the axial direction of the raw wood 3 is fitted and supported by the support shafts 12 .

In addition, it is also possible to carry out the conveyance claw 13 from parallel conveyance by the traveling body 11 as described above to oscillating conveyance to the chuck center of the veneer lace (not shown) using the swing shaft 14 as a fulcrum, as shown in FIG. It is.

Therefore, the temporary center O of the log 3 can be determined by using concentric circles based on the project method described above, or by bringing the pedestal and the detector close to each other at the same distance from above and below, and holding the log 3 on the pedestal. The calculation is made once, and then the log rotation gripping tool 7 is pressed and gripped on both end faces 4 of the log.

At the time of this pressing, the rotation center P of the spindle 6 axis of the log rotation gripping tool 7 and the temporary center O of both butt ends 4 are made to almost match, and the log rotation gripping tool 7 is rotated with respect to the rotation center P. The center K side of the base body 1 is positioned below both the butt ends 4, and the upper parts of both the butt ends 4 are opened to allow the conveying claws 13 to intervene.

That is, a suitable positional relationship means that, as shown in FIGS. 3 and 5, the conveyance claw 13 is placed on the extension of a line segment passing from the center K of the base body 1 to the rotation center P of the spindle 6 shaft.
In this way, the line segment with the shortest distance from the rotation center P to the outer periphery of the base 1 can be obtained. Therefore, the upper openings of the end surfaces 4 at both ends, which are branched by the tangent between this line segment and the outer periphery of the base body 1, are increased, and the gripping area with the conveying claws 13 is increased, resulting in an advantageous clamping state.

When the log rotation gripping tool 7 is pressed, the claws 5 bite into both butt end faces 4 and grip the log 3 while the amount of biting is regulated by the surface 2 of the base 1, and after gripping, the spindle 6 The rotation is transmitted to the log 3 to move it at least once.

As the log 3 rotates, as described above, the log 3
The axis of the log is calculated and the position of the log 3 is corrected as appropriate.

Next, the transport claw 13 is waiting outside the upper part.
is slid on the support shaft 12 or the swing shaft 14 to grasp the opening upper portions of both the butt ends 4, and at the same time, the spindle 6 is retracted and the log rotation gripping tool 7 is removed from both the butt ends 4. let

Thereafter, the raw wood 3 is supported by the conveying claws 13 and conveyed in parallel or oscillatingly to the veneer race, so that its axis is aligned with the chuck center.

"Effects of the invention" As described above, according to the invention, the axis of the spindle 6 is attached to the base 1 on which a plurality of claws 5 are planted on the end surface 4 side of the log 3, with the center of rotation P being eccentric. Since it is fitted from the back side to form the log rotation grip 7, the log 3 has a large diameter, the logs 3 have irregularly shaped end faces 4, and the end faces are broken, cracks, and especially weak parts near the core of the tree. Even with existing logs 3, etc., the core part is included and part of it extends to the tree edge to be gripped, so the gripping area is expanded compared to the conventional small-diameter gripping tool, and a certain number of rotations are possible. can withstand dynamic torque.

Furthermore, since the rotation center K of the log rotation gripping tool 7 is eccentric, the conveyance claws 13 can be synchronously interposed above the openings of both butt ends 4 of the log 3, and do not interfere with each other.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of the device of the present invention;
Fig. 2 is a side view of the same, Fig. 3 is a front view showing the gripping state with the conveyance claw, Fig. 4 is a partially cutaway side view of Fig. 3, and Fig. 5 is another embodiment of Fig. 3. FIG. 1...Substrate, 2...Surface, 3...Log, 4...
Both wood end faces, 5...claw, 6...spindle, 7...
...Gripper for rotating raw wood, 13...Transportation claw.

Claims (1)

[Scope of utility model registration request] A gripping tool for rotating logs, characterized in that a shaft portion of a spindle is fitted from the back side of a base body having a plurality of claws planted on the end surface of the log, with the center of rotation being eccentric.