JPH0126322B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method and apparatus for centering a columnar object, and in particular to a method for centering a columnar object suitable for centering a log when the log is carried into a veneer lace. The present invention relates to a method and an apparatus used for the same.

When manufacturing veneered plywood, a veneer lace equipped with a cutting tool is used to peel and shave raw wood logs.
Cut the obtained long veneer veneer into appropriate dimensions,
A method is adopted in which they are combined in the vertical and horizontal directions and laminated and bonded. In this case, the bark and irregularly shaped protrusions of the logs carried into the veneer lace are removed in advance, and the logs are shaped into a perfect circle.The log is fed into the veneer lace by a charger, and its axis is held by a spindle and carved. Accurately detecting and aligning the shaft center of the raw wood logs is important in reducing the incidence of short veneer waste, making effective use of resources, and maintaining the quality of the plywood. This is an extremely important matter.

FIG. 1 shows an outline of the charger used for centering the raw wood logs mentioned above and transporting them to the veneer lace. In the figure, logs L are carried into the charger from the direction of arrow A by a carry-in conveyor (not shown) and are transferred onto the V-grooves of log log holders 1a and 1b at predetermined positions.
These raw wood log holders 1a and 1b are the fluid cylinders 2
a and 2b in the direction of arrow B, and is raised to a predetermined height corresponding to the image projected by log diameter detection devices 3a and 3b, which will be described later. Centering is performed.

After centering in this way, the fluid cylinders 4a, 4b are operated and the clamp arms 5a,
5b in the axial direction of the log L, and drive clamp claws (not shown) provided on the inner surface of each clamp arm into both ends of the log L. As a result, the log L is clamped by the clamp arms 5a and 5b.
Since the fluid cylinder 2 is in a gripped state between
a, 2b to move the log supports 1a, 1b downward, and move the trolleys 6a, 6b, to which the clamp arms 5a, 5b are attached, along the trolley rails 7a, 7b while keeping the horizontal level. By moving the log L, the axis of the raw wood log L is aligned with the spindles 9a and 9b of the veneer race 8. In this state, when the spindles 9a and 9b are brought close to each other in the axial direction, a spindle pawl 10b (the other one is not shown) provided on the opposing inner surfaces of the spindles 9a and 9b.
bites into the axis of the log L and supports it.

When the centering and positioning of the log L with respect to the veneer race 8 is completed in this way, the clamp arm 5 is moved by operating the fluid cylinders 4a and 4b.
a and 5b are separated from each other in the axial direction, and after their clamp claws (not shown) are removed from the log L, the trolleys 6a and 6b return to their original state (as shown in FIG. 1) by running the trolleys 6a and 6b. and prepare for the next round of logs. In the figure, 11 and 12 indicate an operation panel and a display.

In the above, log diameter detection devices 3a, 3b
For example, an industrial television camera is used, and its image is displayed on the display 12.
This display 12 is equipped with a plurality of concentric annular scale patterns 13, as illustrated in FIG.
The operator displays the log image 2' on the display 12.
The fluid cylinders 2a and 2b are adjusted so that the center of the scale pattern 13 coincides with the center of the scale pattern 13.

As described above, in the conventional method, it is necessary for the operator to center the raw wood logs manually while watching the image on the display, which has been a bottleneck in efforts to save labor.

The present invention has been made in order to eliminate the drawbacks of the conventional methods as described above, and aims to provide a method and device for centering raw wood logs that can be performed automatically, easily and accurately. It is something.

Hereinafter, details of the present invention will be explained with reference to FIGS. 3 to 5.

In FIG. 3, the log L carried into the charger by the carry-in conveyor 14 is transferred onto the log holder 1, lifted up by the fluid cylinder 2 and centered, and then moved by the clamp arm 5. It is shown in FIG. 1 that the veneer is gripped and conveyed along the trolley rail 7 by the trolley 6, suspended by the spindle 9 of the veneer race 8, and cut into a thin veneer by the cutting blade 15. However, in the present invention, instead of using an industrial television camera and a display, it consists of a pair of emitter and receiver installed above the reference level B, which is the lowest point of the pedestal 1. Detector PH is used. This emitter and receiver are connected to the trolley rail 7.
A pair of base pillars 17 planted between the and pedestal 16
(The other one is in a symmetrical position with the log L in between.) They are arranged facing each other at a predetermined height. A window 18 is opened in the clamp arm 5 at an appropriate position so that the light emitted from the emitter enters the receiver unless it is blocked by the log L, and the emitter and the corresponding receiver are placed at the lowest position. The logs are placed at a location where the light is not blocked by the log pedestal 1' in the log holder 1' or the logs placed on the carry-in conveyor and transported.

A centering method of the present invention using a light emitter and a corresponding light receiver in the apparatus of the present invention configured as described above will be explained with reference to FIGS. 4 and 5.

The horizontal position of the detector PH is on the center line ( y - y line) of the V-groove on the top surface of the log holder 1. As mentioned above, the logs carried onto the log pedestal 1 by the carry-in conveyor are shaved in advance and made into a nearly perfect circle, so the axis of the logs is aligned with the y-y line regardless of the diameter. matches.

The diameters of the logs brought in vary in size, but the minimum and maximum dimensions of the logs that can be cut are regulated according to the scale of the charger and Venice lace.

The detector PH detects that when the log pedestal 1 is at the reference level (usually the lowest position), the light is not blocked by the largest diameter of the log L being carried in, and the log L turned sideways is detected. Whenever the upper edge of the log pedestal 1 is raised to block light, the center of the log L is always at the centering center O or a position below this.

The log pedestal 1 on which the log L is placed is gradually lifted upward from the reference level by the fluid cylinder 2. At the same time, as shown in FIG. is activated, and this pulse generator PG generates a pulse every time a certain distance is lifted (for example, one pulse per 1 mm rise). SW is a switch that starts the pulse generator PG at the same time as the log pedestal 1 is raised.

This pulse is sent to the pulse counter PC connected to the pulse generator PG, which starts counting the number of pulses, and the counted pulse number is transferred to the processing device.
Sent to CPU.

The detector PH is shielded from light by reaching the upper edge of the log, and at the same time the processing equipment connected to it
A signal is sent to the CPU, the processing device opens the gate, reads the number of pulses at this time, performs the calculations described below from this number of pulses, and calculates the number of pulses that should be counted until the log reaches the centering position. and sends this result to the comparator COM. After this,
The comparator COM takes in the count number of the pulse counter PC, compares it with the count number from the processing unit CPU, and when the comparison output becomes 0, the control unit
Sends a signal to CON to stop the fluid cylinder from rising. In this state, the axis of the log is always located at the X - Y intersection O in FIG. 4, that is, the centering position, and centering is completed.

Next, the principle of operation will be explained with reference to FIG.

The diameter of the log is D, the number of pulses counted by the pulse counter PC until the log is detected by the detector PH is _C1 , and the center of the log reaches the centering position O after being detected by the detector PH. C ₂ is the number of pulses to be counted until then, x is the distance from the reference level B to the lower edge of the log, l ₁ is the distance from the reference level B to the detector PH, and from the centering center O to the detector PH If the distance of is l ₂ , then
Regardless of the diameter of the log, C ₁ +D+x=l ₁ ……(1) D/2−C ₂ =l ₂ ……(2) ∴C ₁ +2C ₂ +x=l ₁ −2 ₂ ……(3 ) If the inclination angle of the V-shaped receiving groove of the pedestal is θ, then x = D/2 (1/cos θ-1) ... (4) From equations (2) and (4), x = (C ₂ + l ₂ )(1/cosθ−1) …(5) From formulas (3) and (5), C ₂ = (1−1/cosθ+1)(l ₁ −C ₁ )−l ₂ …(6) where l ₁ , l ₂ and θ are values determined by design, so the value of C ₂ can be found from equation (6) once the value of C ₁ is determined.

That is, the processing unit CPU takes in the value of _C1 , performs the calculation of equation (6), and sends the result to the comparator COM.
It is sent out as a reference value.

As described above, according to the present invention, a set of detectors is arranged at a predetermined position, pulse counting is started at the same time as the pedestal starts rising from the reference level, and at the same time the upper end of the log is detected by the detector. The subsequent ascending distance is calculated from the number of counts counted up to that point, and by stopping the ascending when a predetermined ascending distance is reached, it is possible to accurately and quickly center logs of any diameter. Unlike conventional methods, manual operations by the operator are no longer required, resulting in labor savings.

In the case of the trolley type shown in Fig. 3, the log L after centering has been completed is gripped by the clamp arms on the left and right end surfaces of the log, as explained at the beginning of Fig. 3, and is rolled along the trolley rail. move parallel,
It is fed to the spindle of the veneer lace. The log transport device after centering is completed is as follows:
In addition to the horizontal trolley type in which the log moves along the horizontal center line x-x shown in Figure 3, the center of the log
A trolley rail is installed obliquely along an inclined line connecting this point and the center point of the spindle of the veneer race, and the trolley rail is transferred diagonally upward on the inclined line to the veneer race. Furthermore, a swing arm other than a trolley type, for example, is erected with a fulcrum shaft installed on a floor located approximately midway between the base column 17 and the veneer lace 8, and swings toward the base column side or the veneer lace side; Alternatively, a log clamp similar to the clamp arms 5a and 5b shown in FIG. 1 may be attached to a swing arm that is suspended from a fulcrum shaft provided at an intermediate position above the base pillar 17 and the veneer lace, and swings back and forth between the two. In the case of the so-called swing type, which has a function, by adjusting the swing range correctly, the log will be rotated slightly when transferring from the centering position to the veneer lace, but there is no problem and the core The log will be conveyed to the spindle of the veneer lace while maintaining the center of extraction.

As described above, in the present invention, with one detector placed above the reference level, the outer diameter parameter of the columnar object is acquired from the count number from the reference level until the upper edge of the log reaches the detector. Since the number of counts from to the centering position can be calculated, there are fewer restrictions on the degree of freedom in design due to the mounting position of the detector, etc., and the manufacturing cost is also low.

Note that the pedestal is not limited to one having a V-groove on the top surface, and a pedestal with a flat top surface having appropriate positioning means can also be used. Further, the scope of application of the present invention is not limited to the above-mentioned centering of raw wood logs, but can also be widely used for centering various columnar objects having circular, rectangular, or hexagonal cross sections. Furthermore, it has also been adopted for centering for rough stripping of logs that generally have a generally circular cross section and omit shaving, and has achieved some results as a centering tool that is quick and accurate enough to handle rough stripping. Can be done.

Furthermore, the pulse counter PC may be provided separately for _C1 counting and _C2 counting. In this case, the number of pulses compared with the comparator may be only for _C2 counting,
The sum of both pulse numbers may be used.

[Brief explanation of drawings]

1 and 2 are a perspective view and a front view of a display device showing an example of a conventional centering device, FIG. 3 is a side view showing an embodiment of the device of the present invention, and FIG. 4 is a detection in the device of the present invention. FIG. 5 is a block diagram showing an example of a circuit for controlling the lifting and stopping of the log stand used in the apparatus of the present invention. 1... Log log pedestal, 5... Clamp arm,
6...Trolley, 7...Trolley rail, 8...
Plywood lace, 14... Carrying-in conveyor, L... Log log, PH... Detector, PG... Pulse generator, PC... Pulse counter, COM... Comparator,
CPU...processing unit, CON...control unit.

Claims (1)

[Claims] 1. A centering center is set in advance in a space above a reference level, a pedestal on which a columnar object is placed on the upper surface is raised from the reference level, and a detector placed above the reference level detects the columnar object. The arrival of the upper edge of the columnar object is detected, and the remaining distance required for the center of the columnar object to reach the centering center is calculated based on the distance from the reference level to the arrival of the upper edge of the columnar object by the detector, and the center of the columnar object is calculated. A method for centering a columnar object, characterized in that the object is raised until it coincides with the centering center and then stopped. 2. The method for centering a columnar object according to claim 1, wherein the columnar object is a raw wood log to be supplied to the veneer lace. 3. The method for centering a columnar object according to claim 1 or 2, wherein the rising distance of the pedestal is processed by counting pulse signals transmitted in response to the rising. 4. A pedestal that is movable up and down and on which a columnar object is placed, and when this pedestal is at a reference level, it is above the upper edge of the columnar object placed on it, and when the pedestal is raised, the center of the columnar object is A detector that is placed at a position that the upper edge passes through before reaching the centering center and sends a detection signal to the processing device, a pulse generator that emits a pulse corresponding to the lifting distance of the pedestal, and a signal from the pulse generator. A pulse counter that counts the distance from which the columnar object is placed and a rise distance signal from the reference level of the cradle to the detection signal output by the detector is received from the pulse counter, and the remaining rise distance to the centering center is calculated. A centering device for a columnar object, comprising: a processing device that performs calculations; and a control device that receives a signal from the processing device and stops the lifting of the pedestal when the centering center is reached using a signal from a pulse counter. 5. The apparatus for centering a columnar object according to claim 4, wherein the columnar object is a raw wood log supplied to the veneer lace.