JPS6345928B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for adjusting the gap between the cutting edges of a veneer lace by rapidly converting the cutting edge in a stepless manner based on a desired amount of stepping, and in particular to a method for adjusting the gap between the cutting edges. Accordingly, the present invention relates to a method of finely adjusting the advance and retreat of the cutting edge each time when cutting a veneer from a rotated log, in order to control the thickness of the veneer, which changes slightly due to cutting resistance, to a constant constant.

Normally, when rotary cutting raw wood with veneer lace, the spacing between the cutting edges of the planer head is determined by the desired amount of advance and a predetermined reduction amount for this amount of advance, and The wood is cut into veneers by moving the planer stand forward based on a desired amount of advance.

However, even if a veneer is cut from rotating logs by controlling the advance of the planer head at a constant rate based on the desired advance amount, there will be differences in the grade or quality of the individual logs.
In addition, even in a single log, cutting resistance varies depending on conditions such as moisture, cracks, and joints from the surface layer to the core layer, as well as hardness and softness of the wood due to differences in growth conditions in the spring and autumn wood parts. As a result, it is difficult to obtain the desired uniform veneer at all times, and the thickness of the veneer varies slightly from the desired veneer thickness to either thicker or thinner.

For this reason, when composing plywood from veneers that do not have the desired thickness, we have traditionally created the desired veneer thickness based on experience at each plywood factory so that it can be adjusted during the finishing process to meet plywood standards. Slightly correct the amount of stepping to obtain the thickness (slightly increase the amount of feeding of the planer stand),
The current situation is that the veneer is slightly thicker than the desired thickness, and the rate of return on veneer from logs has to be reduced.

In view of the above, the present invention first provides a mechanism that can steplessly and rapidly change the gap between the cutting edges, which is determined by a desired walking amount and a predetermined aperture amount for this walking amount. In addition to adjusting the spacing, a torque detector placed in the feed mechanism detects the amount of variation caused by cutting resistance during rotational cutting, and adjusts the forward and backward movement of the blade edge based on the amount of torque displacement. Examples thereof will be described below based on the accompanying drawings.

A drive device 3 consisting of a DC motor or the like is connected to the spindle 2 of the veneer race 1, and the speed change lever 4 installed on the driver's cab of the veneer race 1 normally switches the speed within the range of 0 to 200 revolutions/minute. be done. The command of the speed change lever 4 is output to the control device 5, which rotates the log 6 at continuously variable speed, and converts the obtained rotation speed into an electrical signal via the rotation detector 7 attached to the drive device 3. Then, the signal is returned to the control device 5.

On the other hand, the planer stand 9 that cuts the veneer 8 from the raw wood 6 that is rotated via the drive device 3 operates at an arbitrary inclination angle with respect to the cutting edge line of the cutter 11 attached to the tool rest 10.
It is composed of a blade holder 14 having a blade 13 that can move forward and backward in accordance with the rotation angle of a block fitted on an eccentric shaft, or as shown in the figure, with the rotation of a feed screw 12. 9 is screwed onto a pair of left and right walking shafts 15, and is movable forward and backward relative to the log 6.

The horizontal distance H between the cutting edge line of the knife 11 and the tip of the cutting edge 13, that is, the cutting edge interval H, varies depending on the thickness of the veneer 8 to be cut, but for a desired walking amount T, Value multiplied by a certain amount of aperture, H = 0.8T~
It is set at around 0.98T.

Therefore, in order to obtain the desired blade gap H, a reducer 16 and a drive device 17 are installed in parallel at the base end of the feed screw 12, and a stepper connected to the drive device 17 is connected to the control device 5. The commands from the amount setting device 18 and the aperture amount setting device 19 are transmitted, and the
4 to an appropriate position on the feed screw 12. This feed screw 12 is equipped with a rotation detector 20 in the same manner as described above, which is fed back to the control device 5 to optimize the feed rate, and also detects the position of the moving blade base 14. A table position detector 21 is installed to convert the amount of movement into an electrical signal and communicate it to the control device 5.

On the other hand, the feed amount of the planer stand 9 screwed onto the feed shaft 15 is determined by an arbitrary step amount from the step amount setting device 18, and The shaft 15 is rotated in the normal direction to move the planer stand 9 forward, and the planer stand feed mechanism 22 has multiple sets of stepped gears, with the drive shaft for rotating the raw wood 6 on the input side and the planer stand 9 on the exit side. Retracted walking mechanism 23
, and set the walking amount mechanically, or the control device 5 calculates the rotation speed of the log 6 and the walking amount from the walking amount setting device 18 to control the rotation of the walking shaft 15. The rotation command is electrically transmitted to the drive device 24 installed on the walking shaft 15. At this time, in order to optimize the amount of step feed, the rotation detector 25 is attached to the step feed axis 15 and returned to the control device 5, as described above.

Next, the torque detector 26, which detects the torque applied to the cutting edge 13 by the cutting resistance generated during cutting of the log 6, is fed forward from the cutting edge stand 14, the planer stand 9, or as shown in the figure, from the planer stand feed mechanism 22. It is disposed between the drive transmission to the shaft 15 and outputs the detected torque amount to the torque level regulator 27 built in the control device 5. This torque level regulator 27 adjusts the amount of torque A that is normally generated based on the desired walking distance, and the amount of constant torque displacement A' that is permissible starting from this torque amount A.
Amount of displacement A′+α, A′− that deviates in the positive or negative direction
In order to keep α within a certain allowable displacement amount A, the drive device 17 is
The feed screw 12 is rotated forward or backward by a certain amount to control fine forward/backward adjustment of the blade opening 13 position.

In the veneer lace 1 having the above configuration, the blade gap H determined by the desired amount of advance and the predetermined amount of aperture for this amount of advance changes the once set planer head 9 to the desired amount of advance. Based on this, the veneer 8 is cut from the rotating log 6 by stepping forward on the walking shaft 15.

When cutting this veneer 8, the blade edge 13 receives cutting resistance.
The torque applied to is detected by the torque detector 26 and sent to the torque level regulator 27 in the control device 5.
However, if this torque is maintained within the ranges A and A' that normally occur with the desired walking distance in FIG. is maintained.

However, when the cutting resistance changes with the properties of the raw wood 6 and the torque reaches the positive direction, that is, the range of A'+α, in the torque level regulator 27, there is a certain amount of displacement that can immediately tolerate this torque. In order to achieve a value within A', a command is given to the drive device 17 via the control device 5, and by slightly reversing the feed screw 12, the cutting edge rest 14 is slightly retracted, and the drawing amount of the cutting edge 13 is reduced. When the torque reaches the negative direction, that is, the range of A'-α,
Contrary to the above description, the feed screw 12 is
By rotating forward by a slight amount, the cutting edge rest 14 is moved forward by a small amount to tighten the amount of narrowing of the cutting edges 13, and the spacing H between the cutting edges is finely adjusted.

As described above, according to the present invention, when the torque applied to the blade edge deviates from the permissible range due to fluctuations in cutting resistance that occur during cutting of a veneer lace, the position of the blade edge is changed from the once set blade position. By finely adjusting the forward and backward movement of the cutting head base each time, the amount of torque displacement is absorbed, so the desired sharp veneer can be obtained at all times.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram showing one embodiment of the present invention,
FIG. 2 is a schematic explanatory diagram showing another embodiment, and FIG. 3 is an explanatory diagram showing the amount of torque displacement. 1...Plywood lace, 2...Spindle, 5...
...control device, 6 ... log, 8 ... veneer, 9 ... plane stand, 12 ... feed screw, 13 ... blade mouth, 14 ...
Cutting head rest, 15...Step feed axis, 18...Step amount setter, 19...Aperture amount setter, 22...Planner stand step feed mechanism, 26...Torque detector, 27...Torque level adjuster .

Claims (1)

[Claims] 1. According to the rotational speed of the spindle that rotates the raw wood, calculate the blade opening interval determined by the desired walking amount and the predetermined aperture amount for this walking amount, and With respect to the cutting edge line of the cutter, the amount of movement of the cutting head base having the cutting edge is determined and its position is adjusted once, and the planer head is moved forward on the walking axis as the spindle rotates based on the desired walking distance. A veneer race characterized in that the cutting edge is kept in constant contact with the raw wood, and the variation in cutting resistance that occurs when cutting a veneer is detected by the amount of torque displacement, and the cutting edge rest is minutely adjusted forward or backward from the aforementioned position. How to adjust the gap between blades.