JPH0737011B2 - Square centering device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for pre-grinding a roughly squared square timber, and before performing the centering of the square timber before mounting the square timber on a feeding vehicle of a sawmill.

[0002]

BACKGROUND OF THE INVENTION Roughly ground square timber is deformed to a slight extent by the internal stress of the wood itself and subsequent drying, so it must be finished ground again before it is used as a final product. That is, as shown in FIG. 5, the roughly ground square timber 1 has G (about 3 to 10 mm) in the horizontal (Y axis) direction and H (vertical (Z axis)) in the vertical direction (X axis) with respect to the longitudinal direction (X axis). 3-
There is a bend of about 10 mm), and there is an error of about ± 0.5 mm on each side of the cross section (square) perpendicular to the axis.

Since the centering and stepping work of finish grinding for correcting these bends and errors requires a high degree of skill, conventionally, it has relied on the experience and intuition of a skilled worker. However, the method of relying on human labor involves considerably difficult work, requires a long time even for a skilled worker, and often fails.
There is a problem of inefficiency. Further, recently, the number of skilled workers is decreasing due to the difficulty of successors, making it difficult to continue the lumber business.

For this reason, recently, a high-class device has been developed which measures the outer shape of a roughly cut timber with an ultrasonic sensor and performs centering and stepping by computer control, but for charging during ultrasonic measurement. This requires a precise servomotor and its drive control circuit, which not only makes the entire apparatus extremely expensive, but also is unsuitable for rounded materials and materials with locally recessed parts.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide an ultrasonic measuring instrument, a computer, a servomotor, and other expensive auxiliary equipment. Another object of the present invention is to provide a square bar centering device that can automatically perform centering and stepping work with a simple device and is easy to maintain.

[0006]

[Means for Solving the Problems] The above-described object is, in a centering device for correcting and grinding a roughly sawed timber, freely movable along the machine base and the longitudinal direction of the machine base (X axis). , And each of the roughly ground squares is gripped from both ends at a fixed point approximately 15% inward of the entire length of the square, and the center of the square at the above two fixed points is aligned with the centering reference axis (Xa axis). A pair of centering units, each of the pair of centering units being provided in a longitudinal direction (X
A frame that moves along the axis) and a vertical axis (Z axis) that is attached to the frame and that is orthogonal to the centering reference axis (Xa axis) and that is directed toward the centering reference axis (Xa axis). A pair of fixed clamps in the Z-axis direction that are driven so as to hold the square bar by approaching each other by equal amounts, and a horizontal axis (Y axis) that is attached to the frame and is orthogonal to the centering reference axis (Xa axis). ) Along the centering reference axis (Xa axis) by a uniform amount, and a pair of Y-axis direction fixed clamps that are driven to hold the square bar, and the pair of Y-axis direction fixed clamps as a whole. This can be achieved by a square bar centering device, which is configured by a mechanism for performing parallel translation in the direction.

[0007]

With the above-described structure, when the pair of centering units grips the roughly ground square timber from both ends at a fixed point approximately 15% inside the entire length of the timber, it automatically becomes the best for the reasons described later. Can be centered. Therefore, the centering and the stepping can be performed by completely unmanned operation without using an expensive computer or an ultrasonic measuring device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. FIG. 1 is a front view showing an overall configuration of an embodiment of a square bar centering device according to the present invention, FIG. 2 is a side view of the centering unit, and FIG. 3 is a main part of a Y-axis direction fixed clamp of the centering unit. FIG. 4 is a side view showing the same, FIG. 4 is a top view thereof, FIG. 5 is an explanatory view showing a bent state of a square timber to be subjected to correction finish grinding, and FIG. 6 is an explanatory view of the principle of a centering method by a square timber centering device according to the present invention. 7 is an operation explanatory view of the Y-axis and Z-axis direction fixed clamps in the present invention, and FIG. 8 is an explanatory view showing a function of the Y-axis and Z-axis direction fixed clamps shown in FIG.

First, the square bar centering device according to the present invention shown in FIG. 1 is roughly classified into a machine base 2 and a pair of centering units 3A, 3B movable along the longitudinal direction (X-axis direction) thereof. And the centering units 3A and 3B are moved appropriately according to the length of the loaded timber 1 to grip the timber 1 from both ends at fixed points approximately 15% of the entire length of the timber, respectively. Put out.

As shown in FIG. 2, the square timber 1 is fed into the centering unit from the left side in FIG. 2 (the back side in FIG. 1), and after the centering is performed, the right feeding vehicle 4 is pushed. It is attached to a cup and sent to a sawmill.

In the centering unit, the square bar 1 is clamped in the Y-axis direction by a pair of pressing tools 31, 32 of the Y-axis direction fixed clamps at a fixed point approximately 15% inward of the entire length from both ends thereof, and in the Z-axis direction. Is clamped by a pair of pressing tools 33, 34 of Z-axis direction fixed clamps, and the center of the square bar 1 is aligned with the centering reference axis (Xa axis) at the two fixed points.

The principle of centering the timber by gripping the inside of the timber 1 at a position approximately 15% of the entire length of the timber from both ends of the timber 1 is described below with reference to FIG. . FIG. 6 is a vertical cross-sectional view (cross-sectional view taken along a plane including the X-axis and Z-axis) of the square bar 1 bent in the Y-axis and Z-axis directions with respect to the longitudinal X-axis as shown in FIG. Is Z
It is shown bent axially. 1a is the center curve of the square bar, 1b is the finished square bar cut out from the square bar 1 by correction grinding, Xa is the central axis of the finished square bar, that is, the centering reference axis, that is, the pushing cup of the feeding vehicle at the time of lumbering. It is an axis that should match the center axis X ₀ of. The rectangular member 1 is also bent in a plane including the X axis and the Y axis, but here, for convenience of description, a cross section of the plane including the X axis and the Z axis will be described.

It is assumed that the rectangular member 1 is uniformly curved in an arc shape, and the center curve 1a thereof is an arc SACBT having a radius R (hereinafter, simply referred to as an arc ST). S and T are on both end faces of the log, and C is a point equidistant from both ends of the log, that is, the midpoint of the arc ST. String S
When the center of T is D, CD is the bending amount H of the square bar. In this case, rational centering is realized by mounting so that the bending amount H is distributed with respect to the push cup center axis X _{0 of the} material feeding vehicle. That is, the middle point E of the CD
Letting A and B be the intersections of a straight line passing through and parallel to the chord ST and the arc ST, press the straight line AEB and the cup center axis X ₀
It would be better to match with.

At this time, the length L _AB of the string AB is calculated as follows. Here, L is a square bar, that is, the length of the string ST, h is the bending amount of the string AB, θ is the central angle of the string ST,
η is a central angle set by the string AB. sin θ = L / (2R) where 2R >> L ∴θ ≈ L / (2R) ───────── (1) H = 2R · sin ² (θ / 4) ≈ (R · θ ² ) / 8 = L ² / 32R ───────── (2) sin η = L _AB / (2R) where 2R >> L _AB ∴ η ≈ L _AB / (2R) ───────── (3) h = 2R · sin ² (η / 4) ≈ (R · η ² ) / 8 = L _AB ² / 32R ───────── (4) Also, h = H / 2 ─── ───── (5) ∴ L _AB / L ≈ (h / H) ^0.5 = (1/2) ^0.5 ≈ 0.707 ──────── (6)

That is, in this case, the distance L between points A and B
_AB is about 70% of the total length L of the timber 1. Therefore, symmetrically with respect to the center plane CD, the points A and B are set so that the distance is about 70% of the total length L of the square timber 1 (that is, the points A and B are located at positions of approximately 15% from both ends of the square timber, respectively). If the square bar is gripped at points A and B, and the center of the cross section of the square bar at those points is pushed to coincide with the cup center axis (X ₀ axis), optimum positioning is performed. Become.

The case where the square bar 1 bent in the Z-axis direction is centered has been described above, but the same applies to the Y-axis direction. In the above description, the centering of the push cup center axis (X ₀ axis) is described, but the centering reference axis Xa of the centering device is set parallel to the X ₀ axis,
On the other hand, after centering the square timber 1, the pushing cup center shaft (X
_It may be moved parallel to the ₀ axis) and transferred to a push cup to be fixed.

The structure of the centering unit used in the square bar centering device according to the present invention will be described. As described above, this centering unit is composed of a pair of centering units 3A and 3B for holding the square bar 1 at the positions corresponding to the positions A and B of about 15% from both ends thereof, respectively. The length can be adjusted appropriately according to the length of the timber so that it will be about 70% of the total length. Since the centering units 3A and 3B have the same configuration, the centering unit 3A will be described here with reference to FIG.

Thus, the centering unit 3A shown in FIG.
Is a horizontal axis (Y) orthogonal to the above-mentioned centering reference axis (Xa axis).
A pair of pressing tools 3 are driven so as to hold the square bar by approaching the centering reference axis (Xa axis) by an equal amount along the axis).
Y-axis fixed clamp consisting of 1,32 and square timbers approaching the centering reference axis (Xa axis) equally along the vertical axis (Z axis) orthogonal to the centering reference axis (Xa axis). It has a Z-axis direction fixed clamp composed of a pair of pressing tools 33 and 34 driven so as to hold (see also FIG. 7).

The pressing tool 33 of the Z-axis direction fixed clamp moves forward and backward toward the centering reference axis Xa by raising and lowering the support frame 33a by the hydraulic cylinder 35. Support frame 33a
One end 33b is fixed to one row of a chain 38 that is looped around a pair of sprockets 37a and 37b that are rotatably attached to the column 36. One end 34b of the support frame 34a of the other pressing member 34 of the Z-axis direction fixed clamp is fixed to the other row of the chain 38. Therefore, when the support frame 33a of the pressing tool 33 is moved up and down by the hydraulic cylinder 35, the supporting frame 34a of the pressing tool 34 is moved by the driven movement of the chain 38.
Moves in the opposite direction from the support frame 33a by equal amounts. Therefore,
The square timber 1 brought into the square timber mounting frame 30 of the centering unit 3A is lifted by the pushing tool 33 of the Z-axis direction fixed clamp, and the other pushing tool 34 which descends in synchronization with the pushing tool 33. The point A on the central axis of the square bar 1 is made to coincide with the Z axis position of the centering reference axis Xa.

Next, the operation of the pair of pressing members 31, 32 of the Y-axis direction fixed clamp will be described with reference to FIGS. 3 and 4. FIG. 3 is a detailed side view of the drive mechanism portion of the pressing tools 31 and 32 seen from the same direction as FIG. 2, and FIG. 4 is a top view thereof. The roller-shaped pressing tools 31 and 32 are attached to the arms 31a and 32a so as to be rotatable about axes parallel to the Z-axis, and the arms 31a and 32a are rotated to support shafts 31b and 32b provided on the substrate 300. It is movably mounted. Further, cam plates 31c and 32c are fixed to the arms 31a and 32a,
Cam grooves 31c 'and 32c' are formed in the cam plates 31c and 32c. The board 300 is provided with a slide plate 301 which can slide in the vertical direction in FIG. 4, and the cam followers 31d and 32d attached to the slide plate 301 are fitted into the cam grooves 31c 'and 32c' of the cam plates 31c and 32c. is doing.

Therefore, when the slide plate 301 is reciprocally driven in the vertical direction (X-axis direction) in FIG. 4 by the air cylinder 302, the cam plates 31c and 32c and the arms 31a and 32a rotate about the support shafts 31b and 32b. The pressing tools 31 and 32 approach and separate from each other by equal amounts. Therefore, by setting the centering reference axis Xa in the middle of the pressing tools 31 and 32,
The point A on the central axis of the square bar 1 is aligned with the Y-axis position of the centering reference axis Xa.

Next, a state in which a square bar is centered by the centering unit configured as described above will be described with reference to FIG. In FIG. 8 (a), a center point A (corresponding to point A in FIG. 6) approximately 15% inward of the entire length of the timber from one end of the timber 1 is Z from the centering reference axis Xa to the Y-axis direction.
It is also displaced in the axial direction. Therefore, as shown in FIG. 8 (b), when the pressing members 33 and 34 of the Z-axis direction fixed clamps are brought close to each other and the square bar 1 is clamped, the square bar 1 moves downward, and the point A and the Xa axis in the Z-axis direction. The positions are matched. At this time, the square bar is immovable in the Z-axis direction, but is in a state of being movable in the Y-axis direction. Next, as shown in FIG. 8 (c), when the pressing members 31, 32 of the Y-axis direction fixed clamp are brought close to each other and the square bar 1 is held, the square bar 1 moves to the right, and the point A and the Xa axis in the Y-axis direction. Are made to coincide with each other, so that the point A and the Xa axis are completely coincided with each other.

From the other end of the timber 1 to the total length of the timber
15% inner center point B (corresponding to point B in FIG. 6)
Similarly, point B by the other centering mechanism 3B.
By making the Xa axis coincide with the Xa axis, the square bar 1 is centered by the best step for the above reason.

After centering the square bar 1 as described above, the pressing tools 33 and 34 of the Z-axis direction fixed clamp are opened,
The entire Y-axis direction fixed clamp is moved while the square 1 is held by the pressing tools 31, 32 of the Y-axis direction fixed clamp.
Allows to move along the frame 40 in the Y-axis direction and, if necessary, Z
The reference axis Xa for centering the square bar 1 is translated in the axial direction.
Is made to coincide with the center axis X ₀ of the pushing cup of the material feeding vehicle 4, and both ends of the square bar are held by the pushing cup.
After that, the pressing tools 31, 32 of the Y-axis direction fixed clamp are released, and the entire Y-axis direction fixed clamp is returned to the original position.
The next operation of centering the timber is performed in the same manner, and the feeding vehicle 4 is reciprocally run toward the sawmill to correct and grind the timber 1. The reason that the pressing members 31, 32 of the Y-axis direction fixed clamp are rollers is that the square members are allowed to move slightly along the X-axis direction when the both ends of the square members 1 are fixed by the pressing cups.

[0025]

Since the present invention is constructed as described above, the present invention does not require expensive auxiliary equipment such as an ultrasonic measuring instrument, a computer, a servomotor, etc. The stepping work can be performed automatically,
It is possible to provide a square bar centering device that is easy to maintain.

The structure of the present invention is not limited to the above-described embodiment. For example, instead of using the hydraulic cylinder 35 as the driving force source of the Z-axis direction fixed clamp, either the sprocket 37a or 37b is used. It may be rotated by a motor, and the drive mechanism of the Y-axis direction fixed clamp can be replaced by various known means. Therefore, the present invention can be easily performed by those skilled in the art from the above description within the scope of the object. It embraces all conceivable alternative embodiments.

[Brief description of drawings]

FIG. 1 is a front view showing the overall configuration of an embodiment of a square bar centering device according to the present invention.

FIG. 2 is a side view of the centering unit.

FIG. 3 is a side view showing a main part of a Y-axis direction fixed clamp of the centering unit.

FIG. 4 is a top view thereof.

FIG. 5 is an explanatory view showing a bent state of a square timber to be corrected and finished to be ground.

FIG. 6 is an explanatory view of the principle of the centering method by the square bar centering device according to the present invention.

FIG. 7 is an operation explanatory view of the Y-axis and Z-axis direction fixed clamps in the present invention.

FIG. 8 is an explanatory diagram showing the function of the Y-axis and Z-axis direction fixed clamps shown in FIG.

[Explanation of symbols]

 1 Square bar 1a Center curve 1b Finished square bar 2 Machine stand 3A, 3B Centering mechanism 31,32 Y-axis direction fixed clamp 31a, 32a Arm 31b, 32b Support shaft 31c, 32c Cam plate 31d, 32d Cam follower 300 Board 301 Slide plate 302 Hydraulic pressure Cylinder 33,34 Z-axis direction fixed clamp 35 Hydraulic cylinder 36 Struts 37a, 37b Sprocket 38 Chain 39 Y-axis direction fixed clamp Translation mechanism 40 Frame

Claims (3)

[Claims] 1. A centering device for correcting and grinding a roughly ground timber (1), which is provided so as to be movable along a machine base (2) and a longitudinal direction of the machine base (X axis). , The rough sawn timber from the both ends of the total length of the timber
A pair of centering units (3A, 3B) for gripping each of the 15% inner fixed points and aligning the center of the square bar at the two fixed points with the centering reference axis (Xa axis) are provided. Each of the centering units (3A, 3B) is mounted on the frame and a frame that moves along the longitudinal direction (X axis) of the machine base.
A pair of fixed clamps in the Z-axis direction that are driven to hold the square bar by approaching the centering reference axis (Xa axis) by an equal amount along a vertical axis (Z axis) orthogonal to the (axis). 33,3
4) and attached to the above frame, and the above-mentioned centering reference axis (Xa
A pair of fixed clamps in the Y-axis direction that are driven so as to hold the square bar by approaching the centering reference axis (Xa axis) by an equal amount along a horizontal axis (referred to as the Y-axis) orthogonal to the axis). 31,3
2) and a mechanism (39) for moving the pair of Y-axis direction fixed clamps (31, 32) as a whole in parallel in the Y-axis and Z-axis directions. 2. The pair of Z-axis direction fixed clamps (33, 34)
2. The square bar centering device according to claim 1, wherein the respective chains are attached to mutually opposite rows of loop-shaped chains (38) wound around a pair of sprockets (37a, 37b). 3. The pair of Y-axis direction fixed clamps (31, 32)
Each of the rollers is rotatable about a vertical axis.
The square bar centering device according to claim 1, which is constituted by (31, 32).