JPH0254202B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cutting raw wood for veneer lace.

Traditionally, raw wood has been cut using a so-called center-driven veneer race, which is configured to supply the power required to cut the raw wood, using a spindle with an appropriate number of claws attached to the tip to cut into the end of the raw wood. When cutting, if the diameter of the spindle is relatively small, the end of the log (substantially including the vicinity thereof) into which the nails will dig may not be able to withstand the supply of power and may split into multiple pieces. Otherwise, there is a marked tendency to damage due to twisting and breaking, and in order to avoid this, it is necessary to increase the diameter of the spindle to the extent that the end of the log into which the nails dig can withstand the supply of power. As a result, thick core stripping (usually 110
mm) remains, resulting in a decrease in yield.

Therefore, in recent years, for example, "veneer lace" (Special Publication No. 56-16729) and "veneer lace" (Special Publication No. 16729)
As disclosed in Japanese Pat. Various techniques have also been developed for cutting raw wood using a so-called peripheral drive type veneer race, which is configured to supply part or all of the power required for cutting from the outer peripheral surface of the raw wood immediately before cutting. It is effective in cutting logs with fragile cores that are difficult to cut with driven veneer laces.

However, even with such a drive system, as the diameter of the raw wood decreases as it is cut, the deflection of the raw wood increases rapidly in inverse proportion to this, and it gradually becomes impossible to cut a veneer veneer with a normal thickness. Due to the difficulties involved, it is not possible to reduce the thickness of the core to a certain extent, and even when power is supplied from the spindle, the maximum thickness of the core to be stripped is approximately 90 mm. It was hot.

On the other hand, for example, "wood rotary cutting equipment"
(Japanese Utility Model Publication No. 56-21506) - "Method for stripping off veneer or similar materials and tools for carrying out the method" (Japanese Patent Publication No. 10960/1983), a central hole is inserted into the shaft of the raw wood. A drive shaft is inserted into the penetrating center hole, and is provided with an appropriate number of claws (former) or an appropriate number of fixed flanges (latter) that are retractable on the outer periphery. An improved technique has been proposed in which the power required for cutting is supplied from inside the log through a When engaging with logs,
Since it acts to split the log, the thickness of the stripped core tends to be unexpectedly thick compared to the thickness of the drilled center hole, so it is not suitable for cutting logs that already have cavities due to rot in the core. Although effective, it was extremely insufficient as an improved technique for reducing the diameter of core stripping.

In view of the above-mentioned conventional situation, the present invention aims to establish and provide a new cutting technology that can reduce the diameter of core stripping compared to the conventional method, thereby contributing to improving the yield in plywood factories. And specifically,
A non-penetrating central hole is drilled from the end surface of at least one side of the raw wood into the shaft core of the raw wood, and a hole having approximately the same thickness as the central hole and having a diameter approximately the same as that of the central hole is drilled into the central hole, and at the tip. A log support shaft with excellent rigidity provided with an appropriate number of claws is inserted until the claws bite into the log, and at least a part of the power required for cutting the log is supplied from the log support shaft to the log. This cutting method is characterized by the following.

According to the cutting method configured as described above, not only the bottom part of the center hole (center part of the log) corresponding to the end of the log when using the center-driven veneer race, but also the peripheral part of the center hole (the center part of the log) (the end of the log) also acts to prevent damage to the log by counteracting the power supplied by the claws of the log support shaft, so even if the log support shaft is thinner than a conventional spindle, the probability of damage to the log is reduced. The log support shaft, which has low friction and excellent rigidity, works to reduce the deflection of the log, so even if the diameter of the log is reduced below the conventional limit, it is possible to cut a veneer veneer with a normal thickness. However, unlike in the case of the previously known improved technique, the claws of the log support shaft do not protrude from the shaft in the distal direction and do not act to split the log when engaged with the log. It is effective because it is possible to cut the raw wood very close to the center hole, and in general, it is possible to make the diameter of the stripped core much smaller than in the past, and it is possible to improve the yield.

Hereinafter, the present invention will be described in more detail with reference to an example of implementation illustrated in the drawings.

The cutting method according to the present invention uses a drilling tool (not shown) such as various drills, for example, as shown in FIG. 1 or 2.
As illustrated in the figure, a central hole 2 that does not penetrate through the axis of the log 1 is drilled from the end surface of at least one side of the log 1, and the As illustrated in FIG. 10, a log support shaft 3 made of metal or the like with excellent rigidity is provided with an appropriate number of claws 4 at its tip, has approximately the same thickness as the center hole 2, and is made of metal or the like. As illustrated in Figure 4,
The claw 4 is inserted into the center hole 2 until it bites into the log 1, and as illustrated in FIG. The log is supplied from the log support shaft 3 and the veneer veneer 10 is cut.

In addition, 6 in FIG. 4 is a spindle similar to a known spindle, which has an appropriate number of claws 7 attached to the tip in order to directly support the other end surface of the raw wood 1. The length of the log support shaft 3 is made substantially equal to that of the log support shaft 3, and desirably, a part of the power required for cutting the log 1 can be supplied.

The cutting method according to the present invention is carried out, for example, as described above, and as is clear from the figures,
Regarding the power supply by the claw 4 of the log support shaft 3,
Not only the bottom surface of the center hole 2 with which the pawl 4 engages, but also the surrounding portion of the center hole 2 located closer to the end surface than the bottom surface serves to prevent damage to the log 1. Even if the log support shaft 3 is thinner than a conventional spindle, the probability that the log 1 will be damaged is lower, and the log support shaft 3, which has excellent rigidity, acts to reduce the deflection of the log 1. Even if the diameter is reduced to below the limit, a veneer veneer 10 having a normal thickness can be cut,
However, unlike in the case of the previously known improved technique, the claws 4 of the log support shaft 3 do not protrude in the distal direction from the shaft portion, but act to split the log 1 when engaged with the log 1. Therefore, it is possible to cut the raw wood 1 very close to the center hole 2, and in general, it is possible to make the diameter of the cored core even smaller than in the past, which is effective because the yield can be improved. be.

Incidentally, if the log support shaft is made of metal, its rigidity is approximately 20 times or more that of wood, and the deflection of the log support shaft itself can be almost ignored. limited to non-existent parts,
However, according to the well-known calculation formula for deflection, the amount of deflection in this type of support increases or decreases in proportion to the cube of the support length. It is natural that the deflection of the log will be dramatically reduced.According to experiments, various center holes with a diameter of 40 to 60 mm and a depth of 1 to 4 times the diameter are drilled into both ends of three-meter logs. At the same time, all of the power required for cutting is supplied from the log support shaft that fits tightly into each center hole,
It was possible to remove veneer veneer with a normal thickness until the core diameter reached 60 to 80 mm.

The example shown in FIG. 12 shows a rotating body 14 having a large number of protrusions 15 around it, as illustrated in FIG. 11, for example.
The piercing body 15 is fixedly attached to a plane stand (not shown) or the like, or as necessary, so that the piercing body 15 can pierce both the outer circumferential surface of the raw wood near the cutting edge of the cutting knife 9 and the veneer veneer 10 immediately after cutting. Accordingly, the veneer race is configured to be movable in the centripetal direction of the log using moving means such as hydraulic pressure or screws, and is configured to supply the power required for cutting from the outer peripheral surface of the log immediately before cutting via the rotating body 14. 16 in the figure shows an example of implementing the present invention.
is a pressure bar installed on the planer stand to press the vicinity of the boundary between the log 1 and the veneer veneer 10;
Reference numeral 17 denotes a peeling member provided on the plane stand in order to peel off the veneer veneer 10 stuck to the piercing body 15.

If such a configuration is adopted, it becomes possible to reduce the power supply from the log support shaft due to the power burden from the rotating body, and when combining the conventional center drive type and peripheral drive type. However, as mentioned earlier, the deflection of the log is reduced with the intervention of the log support shaft, so it is possible to more reliably engage the piercing body of the rotating body with the outer circumferential surface of the log. In the embodiment described above, a synergistic effect is achieved that allows power to be transmitted more accurately even to the surrounding area of the center hole, where transmission of power was somewhat unstable. This also makes it possible to make the log support shaft even thinner, which is effective in reducing the diameter of core stripping.

In addition, experimentally, various center holes with a diameter of 30 to 50 mm and a depth of at least three times the diameter were drilled into both ends of three-inch logs, and each center hole was fitted without loosening. By supplying the power required for cutting from the combined log support shaft and rotating body, it was possible to cut veneer veneer with a normal thickness until the core diameter reached 45 to 65 mm.

The depth of the center hole is not limited to the depth of each of the above experimental examples, but can be selected as appropriate depending on various conditions such as the initial log diameter, log length, tree species, and the thickness of the veneer veneer to be cut. There is no problem, and even if the thickness of the hole does not necessarily match the log support axis, there is no practical problem as long as the error is absorbed by the elasticity of the log, and the location of the hole does not necessarily match the log support axis. For example, in order to effectively remove existing growth stress cracks that radially originate from tree rings as a cause of damage to logs, drilling is not limited to the shaft core portion corresponding to the external shape of the log. , may be set as appropriate, and as is clear from the figure, the bottom surface does not necessarily have to be perpendicular to the axis.

As for the log support shaft, it can be made of highly rigid metals such as stainless steel or plain steel with plating treatment if necessary, or other highly rigid materials, in the same way as known spindles. It is most convenient to prepare the veneer race in such a way that it can be moved in and out of the veneer race by means of hydraulic pressure, screws, etc. If necessary, a well-known double spindle mechanism can be used as shown in FIG. Until then, it is possible to adopt a configuration in which power is supplied from the large spindle 5, but as illustrated in FIG. After being inserted into the center hole of the veneer lace, it may be held by a chuck 8 of an appropriate mechanism provided on the veneer lace.

Furthermore, regarding the shape and number of the claws attached to the tip of the log support shaft, in addition to the example shown, there are various shapes and numbers similar to the claws of known spindles. The shape and number of claws should be as long as they can transmit power effectively without damaging them as much as possible.From the viewpoint of transmitting power, the length of the claws should be relatively long within the range that does not damage the claws themselves. However, in any case, the tip of the log support shaft (especially the claw) is relatively subject to wear and tear, so either only the claw is removably provided, as in a well-known spare blade, or a blade according to Fig. 8 is used. It would be convenient if the distal end side of the joint shown in 11 is detachable so that it can be replaced at any time.
Insertion into the center hole is facilitated by chamfering the tip end side of the raw wood support shaft including the claws into an appropriate shape, such as the arc-shaped chamfered portion shown in 2 and 13.

On the other hand, regarding the shape of the rotating body, in addition to the shape as in the above embodiment, which is suitable for installing a pressure bar etc., for example, a shape in which a large number of protrusions are arranged in a distributed manner, or a shape in which a large number of protrusions are arranged as an axis, may be used. Various modifications have been made, such as one in which the blades are arranged in a double row parallel to the core.
In addition to the position as in the above embodiment, which is effective for both imparting a tendering effect to the veneer veneer, the piercing body is located on the outer periphery of the log near the cutting edge of the cutting blade, which is effective only for preventing blade clogging at the cutting part. Various changes can be made, such as a position where a chisel can be pierced, or a position similar to the known back-up roll, which is effective in reducing the bending of logs.Furthermore, the shape of the attached piercing body can also be changed.
In addition to the shape shown in the above embodiment, which has excellent power transmission and ease of piercing, various modifications can be made, such as needle-like, conical, and pyramidal shapes. Any rotating body that can supply power to the outer peripheral surface of the log based on engagement with the surface is sufficient.

Furthermore, regarding the form of power supply between the rotating body and the log support shaft, it is most common to supply power at approximately the same rate from beginning to end. In order to prevent damage due to twisting during the process, it is possible to adopt a configuration in which the supply is given priority from the rotating body at the beginning.
There is no problem as long as the start timing and proportional distribution ratio of each power supply are appropriately set in consideration of various cutting conditions, and as a means for synchronizing them, for example, "veneer lace" (Japanese Patent Application Laid-Open No. 54-298) It is possible to employ various conventionally known mechanical and electrical tuning means, such as the tuning means disclosed in .

[Brief explanation of the drawing]

The drawings are for explaining the present invention, and FIGS. 1 and 2 are cross-sectional views of logs with a center hole drilled in them, and FIGS. 3 to 6 are cross-sectional views of the logs with the center hole and the log support shaft. Seventh schematic cross-sectional explanatory diagram for explaining the engaged state
The figure is a side cross-sectional explanatory view to explain the state in which logs are cut by supplying power exclusively from the log support shaft, Figure 8 is a partial perspective view of the log support shaft, and Figure 9 is a partial front view of the log support shaft. , Figure 10 is a side view of Figure 9,
FIG. 1 is a partial front view of the rotating body, and FIG. 12 is a side sectional explanatory view for explaining the state in which raw wood is cut by supplying power from the log support shaft and the rotating body. 1... Log, 2... Center hole, 3, 3a... Log support shaft, 4... Claw, 5... Large spindle, 6...
Spindle, 9...Cutting blade, 10...Plywood veneer, 14...Rotating body, 15...Punching body.

Claims (1)

[Scope of Claims] 1. A non-penetrating central hole is drilled from the end surface of at least one side of the log into the core of the log, and a hole of approximately the same thickness as the center hole is drilled into the center hole. A log support shaft having excellent rigidity and having an appropriate number of claws attached to the tip is inserted until the claws bite into the log, and at least a part of the power required for cutting the log is transferred to the log support shaft. A method for cutting raw wood in veneer lace, characterized by supplying the raw wood from the raw wood and cutting the raw wood. 2. A method for cutting logs using a veneer race according to claim 1, which uses a veneer race configured to supply power required for cutting exclusively through a log support shaft. 3. A patent claim that uses a veneer lace that has a large number of piercing bodies around it and is configured so that the power required for cutting is supplied from a rotary body that is positioned so that the piercing bodies can pierce the outer circumferential surface of the raw wood. A method for cutting raw wood for veneer lace as described in Item 1. 4. Claim 3, comprising a veneer race equipped with a rotating body in a position where the piercing body can pierce both the outer circumferential surface of the raw wood near the cutting edge of the cutting blade and the veneer veneer immediately after cutting. The method for cutting raw wood for veneer lace described in . 5. A method for cutting raw wood with a veneer race according to claim 3, which uses a veneer race equipped with a rotating body at a position where the piercing body can pierce only the outer peripheral surface of the raw wood near the cutting edge of a cutting blade. .