JPS6124147B2 - - 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, it can be raised and lowered in the direction of arrow B, and is raised to a predetermined height corresponding to the projected image by log diameter detection devices 3a and 3b, which will be described later, and the outside diameter of the log and the projected image are measured. Centering is then 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 aligns the center of the log image 2' on the display 12 with the center of the scale pattern 13.
The fluid cylinders 2a, 2b will be adjusted.

In this way, the conventional method requires the operator to center the logs manually while watching the image on the display, which is one way 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 pedestal 1, lifted and lowered by the fluid cylinder 2 for centering, 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, at least two, preferably three sets of projectors PH1, PH2, PH3 and a receiver (not shown) are used. . These light emitters and receivers face each other at a predetermined height on a pair of base posts 17 (the other one is located at a symmetrical position across the log L) installed between the trolley rail 7 and the pedestal 16. It is arranged as follows. and floodlight PH
2. Unless the light emitted from PH3 is blocked by the log L, a window 18 is opened at an appropriate position in the clamp arm 5 so that the light enters the corresponding light receiver, and a window 18 is opened at an appropriate position in the light projector PH1. The light receiver is placed at a position where the light is not blocked by the log holder 1 located at the lowest position or by the logs placed on the carry-in conveyor and transported.

The details of the positional relationship between the projectors PH1, PH2, PH3 and their corresponding light receivers in the apparatus of the present invention constructed as described above will be explained with reference to FIG. Note that in the following description, the light projector and light receiver that are combined together will be referred to as a detector.

The horizontal positions of the detectors PH1, PH2, and PH3 are on the center line (y-y line) of the V-groove on the top surface of the log round 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.

Although the diameters of the logs brought in vary in size, the minimum and maximum dimensions of the logs that can be cut are regulated according to the scale of the charger and veneer lace. Detector PH1 is located at a position where, when the log holder is at the reference position (usually the lowest position), the light is always blocked by the log, regardless of the diameter of the log being carried in, and It is placed at a position farther from the centering position (the intersection of the XY axes) than the radius of the maximum diameter log to be centered. Detector
PH2 is located at a position where the light is exactly blocked by the upper edge of the log with the smallest diameter when the log is centered, in other words, it is placed at a position above the centering position by the radius of the log with the minimum diameter. . Also detector PH3
is placed slightly above the position where the upper edge of the log log is exactly shielded from light when the log log with the largest diameter is carried onto the log pedestal at the reference position.

The log pedestal 1 on which the log L is placed is gradually lifted upward by a fluid cylinder, and at this time, as shown in FIG. 5, it is raised a certain distance by the pulse generator PG connected to it. pulse per degree (for example, one per 1 mm rise).

The detector PH1 sends a signal to the pulse counter PC1 connected thereto to start counting the pulses at the same time as the lower end of the log finishes passing.

When the detectors PH2 and PH3 reach the upper end of the log, they simultaneously send a signal to the pulse counters PC2 and PC3 connected thereto to count the pulses. Pulse counter PC2 and PC3
One of the outputs is selected by the changeover switch SW1, and the output is led to the adder ADD and added together with the output of the pulse counter PC1. Setting device EST1
One of the set values of and EST2 is selected by a switch SW2 interlocked with the switch SW1, and compared with the output of the adder ADD by a comparator COM.
When the comparator output becomes zero, the fluid cylinder stops rising. In that state, the axis of the log is always in the 4th position.
It will be located at the XY intersection in the figure, and centering will be completed.

Next, the principle of operation will be explained. In addition, if the diameter of the raw wood log to be processed is about 200 mm at the minimum and 400 mm at the maximum, each dimension in Figures 4 and 6 is S1 =
240mm, S2=100mm, S3=170mm,
Further, when 1 mm = 1 count, the setting device EST1 in FIG. 5 is set to 140 counts, and the setting device EST2 is set to 70 counts.

Example (When the raw wood log is 200 mm) In Figure 6 [] C1=S1-d/2=240-100=140 C2=d/2-S2=100-100=0 ∴C1+C2=140+0=140 Therefore, As shown in Figure 5, switch SW1,
If SW2 is connected to PC2 and EST1 side, C1=
140, the comparator output is zero-centered when C2=0.

Example (when log is 340mm) In this case, in Figure 6 [] C1=S1-d/2=240-170=70 C2=d/2-S2=170-100=70 ∴C1+C2=70+70=140 Therefore, it is the same as the case in FIG.

Example (When log diameter is 370mm) In this case, in Figure 6 [] C1=S1-d/2=240-185=55 C3=d/2-S3=185-170=15 ∴C1+C3=55+15= 70 Therefore, switches SW1 and SW2 in Fig. 5
If is connected to the PC3 and EST2 sides and the number of comparisons of the comparator COM is set to 70 counts, the comparator output will be zero at the position of C1 = 55 and centering will be performed.

As described above, according to the present invention, three sets of detectors are arranged at predetermined positions to detect the passage of the lower and upper edges of the log being raised and lowered, and pulse counting is started from there. When the total value of the logs reaches a predetermined set value, the ascent is stopped, making it possible to center logs of any diameter accurately and quickly. This is no longer necessary, resulting in labor savings. In addition, the above-mentioned switch SW1,
Switching of SW2 can also be done automatically by adding a simple electric circuit based on the presence or absence of the output of detector PH2.

In the above explanation, an example has been described in which a light emitter and a light receiver arranged on both sides of the log are used to detect the upper and lower edges of the log. However, the present invention is not limited to this, and the present invention is not limited to this. Other detectors can be used, such as a type of detector that uses reflected light from an end face or a limit switch.

Furthermore, the pedestal is not limited to one with a V-groove on the top surface.
A flat-topped pedestal with suitable 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. In addition, the detector PH2 should be installed movably with respect to the log, or the range of the target log diameter should always be unobstructed when the detector PH2 is at the reference position, and when the detector PH2 is at the centering position. If the detector PH2 is always shielded from light, the detector PH3 can be omitted. In this case, the pulse counter PC3, setter EST1, and switches SW1 and SW2 of the rise stop control circuit shown in FIG. 5 are omitted.

In addition, in the above embodiment, an example was explained in which centering was performed while moving the raw wood log vertically upward, but the present invention is not limited to such embodiment, and the log was moved vertically downward, diagonally, or It is also possible to perform centering while moving in the horizontal direction.

[Brief explanation of the drawing]

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 lifting stop control circuit for the log holder used in the apparatus of the present invention, and FIG. 6 is an explanatory diagram of the operation of the method and apparatus of the present invention. be. 1... Log log pedestal, 5... Clamp arm,
6...Trolley, 7...Trolley rail, 8...
Plywood rail, 14... Carrying conveyor, L... Raw logs, PH1, PH2, PH3... Detector, PG...
...Pulse generator, PC1, PC2, PC3...
Pulse counter, ADD...Adder, EST1,
EST2...Count number setter, COM...Comparator.

Claims (1)

[Claims] 1. A first detector disposed at a distance greater than or equal to the radius of the columnar object to be centered from the centering position, and a detector located on the opposite side of the first detector across the centering position. A second spacer spaced apart from the centering position by a distance equal to or less than the radius of the columnar object to be centered from the centering position.
A columnar object to be centered is moved horizontally between the detectors from the first detector side to the second detector side, and at the same time as the columnar object finishes passing, the first detector moves the columnar object according to the moving distance. The second detector generates a signal corresponding to the travel distance at the same time as the columnar object arrives, adds this signal to the above signal, and when the total value reaches a certain value, the columnar object is detected. A method for centering a columnar object, characterized by stopping the movement of the object and clamping it at that position. 2. The method for centering a columnar object according to claim 1, wherein the columnar object is raw wood for veneer lace. 3. The method for centering a columnar object according to claim 1 or 2, wherein the signal corresponding to the moving distance is a number of pulse signals corresponding to the moving distance of the columnar object. 4. The method for centering a columnar object according to claim 1, wherein the moving direction is a vertical direction. 5. A liftable pedestal having a receiving portion on the upper surface, at least two detectors arranged vertically apart from each other on the pedestal, and an output of one of these detectors. A pulse counter counts the number of generated pulses after the columnar object placed on a pedestal has passed, and the output of another detector counts the number of pulses generated after the columnar object arrives. A pulse counter, an adder that adds the counts of both counters, a count number setter, and an output that outputs when the output of this adder and the output of the count number setter are compared and become equal. a comparator for stopping the vertical movement of the columnar object;
A centering device for a columnar object, comprising a conveyance device that maintains the stopped columnar object at that level and moves it in parallel. 6. The apparatus for centering a columnar object according to claim 5, wherein the columnar object is a log made of veneer lace. 7 Consisting of three detectors, with at least two detectors arranged vertically apart, the first detector being shielded from light when it is in the reference position for a columnar object of any diameter. placed in the second position
The second detector is placed in a position where the light is blocked when the columnar object with the smallest diameter moves up and down to the centering position, and the third detector is placed in a position where the light is not blocked even when the columnar object with the largest diameter is at the reference position. A centering device for a columnar object according to claim 5 or 6, which is located at a position. 8. The apparatus for centering a columnar object according to any one of claims 5 to 7, wherein the pulse counter and setting device changeover switch is controlled depending on whether or not the second detector is shielded from light. .