JP3172879B2 - Circular sawing machine and pressing device for sawn timber used for it - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circular sawing machine capable of efficiently and stably cutting small-sized sawn timber, and to a sawing machine pressing device used therefor.

[0002]

2. Description of the Related Art Twin circular saw machines having two circular saw blades are:
Since it is possible to grind two places at a time, it can be conveniently used, for example, to remove the ears on both sides of the sawn timber, or to remove only harmful joints in a narrow width. it can.

[0003] This is constituted by combining two circular saw blades and a table for conveying sawn material, and the sawn material can be supplied to the circular saw blade manually or by power feed.

[0004] In the type of power feeding of sawn timber, a caterpillar device or a chain device which is continuous before and after the circular saw blade is used as a feed device, and its conveying surface is bent downward at the position of the circular saw blade. By doing so, it is usual to avoid interference with the circular saw blade. It is also widely practiced to dispose a pressing roller for pressing the sawn material downward before and after the circular saw blade to increase the conveying force applied to the sawn material.

[0005]

According to the prior art, the processing range of the sawn timber is limited, and the problem that it is difficult to work a short small sawn timber cannot be avoided. That is, in general, the bent portion of the caterpillar device or the chain device needs to have a long margin before and after the circular saw blade from the viewpoint of running stability and durability of the caterpillar device and the like, and the pressing roller has It must be disposed farther away from the bent portion of the caterpillar device or the like. At this time, unless the ground material contacts at least one of the pressing rollers, a sufficient transport force cannot be obtained. Therefore, the minimum length of the processed sawn material needs to be at least about 1 m or more.

In view of the above-mentioned problems in the prior art, the object of the present invention is to provide a caterpillar device that is divided before and after a circular saw blade, so that even small-sized sawn lumber can be efficiently used. An object of the present invention is to provide a circular saw capable of performing a stable cutting process and a pressing device for a sawn wood used for the circular saw.

[0007]

Means for Solving the Problems To achieve the above object, a first invention according to the present application comprises a fixed frame, a movable frame mounted on the fixed frame so as to be able to move back and forth, and a movable frame together with a main motor. A spindle mounted on the main frame, an outer cylinder mounted on a fixed frame coaxially with the main spindle, and spline-coupled to the main spindle, and a fixed blade mounted on a tip of the outer cylinder,
It is equipped with a movable blade attached to the tip of the main shaft, a fixed blade, and a caterpillar device for dividing and arranging the saw blade separated and arranged before and after the movable blade, and fixed before and after each of the fixed blade and the movable blade. The gist of the present invention is to provide a pressing device mounted on a frame and a movable frame.

[0008] Each pressing device can take an operating position intersecting with the corresponding fixed blade or movable blade.

Further, a ground material supporting surface having the same height as the conveying surface of the caterpillar device can be provided below the fixed blade and the movable blade.

A second aspect of the present invention comprises a bracket swingably mounted on a lower portion of a base and a plurality of feed chains running along the outer periphery of the common bracket. The gist of the present invention is that the cutting edge of the circular saw blade can be stored at the front end of the saw blade and is driven at the same traveling speed as the transport speed of the sawn timber.

The bracket can be swung up and down via an air cylinder.

[0012]

According to the first aspect of the invention, since the caterpillar device is divided and disposed before and after the fixed blade and the movable blade, its transport surface is located very close to the fixed blade and the movable blade. In addition to the fixed blade and the movable blade, pressing devices disposed before and after each of the fixed blade and the movable blade press the ground material on the caterpillar device, and can provide a stable conveying force to the short ground material. In addition, the pressing device corresponding to the movable blade is mounted on the movable frame, and even if the movable frame is moved and the movable blade is relatively moved with respect to the fixed blade, there is a possibility that the relative positional relationship with respect to the movable blade fluctuates. Absent.

Each of the pressing devices intersects with the corresponding fixed blade or movable blade at the operating position, so that the grind is substantially conveyed to the grind even at a position where it comes into contact with the fixed blade or the movable blade. And the section in which the conveying force of the sawn timber is lost can be minimized.

If a grind support surface having the same height as the transport surface of the caterpillar device is provided below the fixed blade and the movable blade, the grind support surface is also provided between the upstream caterpillar device and the downstream caterpillar device. Thus, the sawn timber can be supported, and even a short sawn timber can be processed extremely stably without the risk of inadvertently disturbing the posture.

According to the second aspect of the present invention, the plurality of feed chains are driven along the outer periphery of the common bracket at the same traveling speed as the transport speed of the sawn timber, so that the feed chains are widely and uniformly applied to the sawn timber. This makes it possible to apply a stable conveying force to the sawn timber over the entire length of the feed chain. In addition, the feed chain can easily intersect with the edge of the circular saw blade by storing the edge of the circular saw blade at the end of the bracket, so that more stable transport force can be applied to the sawn wood It is.

By swinging the bracket via the air cylinder, the feed chain can be set to any desired travel angle by expanding and contracting the air cylinder as needed.

[0017]

Embodiments will be described below with reference to the drawings.

The circular saw machine includes track blades 10 and 20 which are divided and disposed before and after the fixed blade S1 and the movable blade S2, and before and after the fixed blade S1 and the movable blade S2. (See FIGS. 1 and 2). However, fixed blade S1 and movable blade S
2 is a circular saw blade.

The circular saw has a fixed frame 50 as a whole,
The caterpillar devices 10 and 20 are assembled to the movable frame 60 (FIG. 3), and are shared by another fixed frame 11.
Has been assembled. The fixed frame 11 is connected to the front surface of the fixed frame 50.

The fixed frame 50 is a box-shaped frame whose rear and upper parts are open (FIGS. 2 and 4). Guide rails 51 and 51 are disposed on the upper edge of the fixed frame 50. I have. Further, a spline bearing 52 is attached to a front upper portion of the fixed frame 50 via a bracket 52a.

The movable frame 60 is mounted on the fixed frame 50 so as to be able to move back and forth (FIGS. 3 and 4). The movable frame 60 has a rear part formed in a box shape with a bottom and a front part formed in a vertically open frame shape.
It is possible to smoothly move along the guide rails 51, 51 via 1, 61.

A bearing 53 is provided on a side surface of the fixed frame 50.
A screw shaft 53 is provided via a and 53a. The screw shaft 53 is screwed to a screw bracket 62 that is vertically provided on a side surface of the movable frame 60, and one end of the screw shaft 53 is connected to a feed motor 53c via a timing belt 53b.

At the rear of the movable frame 60, a base Ma
The main motor M is incorporated via the main motor M. On the other hand, below the movable frame 60, a main shaft 63 is provided.
Is mounted on the movable frame 60 via a bearing 63 a vertically suspended from the movable frame 60, and penetrates the spline bearing 52 on the fixed frame 50 side forward and backward. Also, the spindle 63
Are connected to the main motor M via V belts Mb, Mb.

The main shaft 63 is a spline shaft (FIG. 5), and is spline-coupled to the inner ring 52b of the spline bearing 52. The spline bearing 52 is fixed to the fixed frame 50 via the outer ring 52c and the bracket 52a.
Attached to. An outer cylinder 63b with both flanges is connected to the front end face of the inner ring 52b. The outer cylinder 63b is mounted on the fixed frame 50 coaxially with the main shaft 63 via a spline bearing 52, and is connected to the main shaft 63 by a spline. Are combined.

A fixed blade S1 is attached to a tip of the outer cylinder 63b via a tightening screw 63c. Spline bearing 5
2. A movable blade S2 is attached to the tip of the main shaft 63 penetrating the outer cylinder 63b via rings 63d, 63d and a nut 63e.

On the bottom surface of the movable frame 60, legs 64, 6
4 are provided vertically (FIGS. 2 and 4). An auxiliary frame 65 is horizontally connected to lower ends of the legs 64, 64, and the auxiliary frame 65 protrudes forward of the fixed frame 50.
Below the auxiliary frame 65, fixed frames 50, 11
The guide rods 65a, 65a are slidably penetrated by sliders 65b, 65b projecting from the lower surface of the auxiliary frame 65.

At the tip of the auxiliary frame 65, a dust removing duct 66 is provided upright. The dust removing duct 66 has a movable blade S2.
On the other hand, the upper end is expanded in a triangular shape so as to cover a part of the movable blade S2 from below. Also, the dust removal duct 66
The upper end surface is a ground material support surface 66a, 66a having the same height as the transport surface of the caterpillar device 10, 20. At the lower part of the dust removal duct 66, the exhaust hose 6 is connected via a joint 66c.
6b can be connected.

A dust removal duct 54 having substantially the same shape as the dust removal duct 66 is also provided for the fixed blade S1. The dust removing duct 54 has sawn wood supporting surfaces 54a, 54a, and the joint 5
The exhaust hose 54b can be connected via 4c. The dust removing duct 54 is fixed to the fixed frame 11 via a spacer 54d.

The caterpillar devices 10 and 20 are incorporated in a common fixed frame 11, and are disposed separately before and after the fixed blade S1 and the movable blade S2 (FIGS. 1 and 3).

Each of the caterpillar devices 10 and 20 has 3
The tracks 13, 23 are extended in an inverted triangular shape via the sprockets 12, 12,..., 22, 22,..., And the upper surfaces of the tracks 13, 23 form a horizontal conveying surface having the same height. I have. The caterpillar devices 10 and 20 are
Sprockets 14a, 1a on the downstream side of the former and on the upstream side of the latter
The caterpillar device 20 on the downstream side is connected to a drive motor 15 via a drive chain 15a. Therefore, the caterpillar devices 10 and 20 can be simultaneously driven by the common drive motor 15. The drive motor 15 is a variable speed motor, and is installed on a base 15 b projecting from a side surface of the fixed frame 50.

Before and after the movable blade S2, pressing devices 30, 4
0 is provided. The pressing devices 30 and 40 are attached to both side surfaces of the front end of the movable frame 60 so that the relative positional relationship with the movable blade S2 does not change even if the movable frame 60 moves back and forth.

The pressing device 30 includes a vertically long U-shaped base 3.
1 and air cylinders 32, 33, a motor 34, and feed chains 35, 35,... As main members (FIGS. 1, 6).

A guide rod 31 is provided inside the base 31.
a and 31a are attached. In addition, the air cylinder 32
Is fixed to the upper surface of the base 31, and the motor 34 is fixed to the lower rear portion of the base 31. A shaft 36 is mounted on the lower surface of the base 31 via bearings 36a, 36a.
One end of the shaft 36 is connected to the motor 3 via a drive chain 34a.
4. The other end of the shaft 36 has a bracket 3
6b is swingably mounted, and sprockets 36c, 36
c is fixed (FIGS. 6 and 7).

The bracket 36b has a groove 35 at its tip.
A chain guide 35a having a1 is attached, and a plurality of feed chains 35, 35, ... are bridged between the sprockets 36c, 36c and the tip of the chain guide 35a, and are shared by the chain guide 35a. It can travel along the outer periphery of the bracket 36b. The feed chains 35 are divided into a single type and a double type.
b. The movable blade S2 corresponds to the concave groove 35a1 of the chain guide 35a.

The air cylinder 33 is swingably mounted on an upper portion of the base 31 via a bracket 33a, and a rod 33b of the air cylinder 33 is pin-connected to a side surface of the bracket 36b. Therefore, the air cylinder 33
Is extended and retracted, the bracket 36b is swung up and down around the shaft 36, and the running angle of the feed chains 35, 35... Can be arbitrarily changed.

The pressing device 40 has substantially the same structure as the pressing device 30 (FIGS. 1 and 3). However, the pressing device 40 mounts a roller 37 at the tip of a shaft 36 instead of the feed chains 35, 35,.
Another roller 38 having a concave groove 38a is pivotally mounted on the tip of the bracket 36b. The rod 33b of the air cylinder 33 is pin-connected to a lever-like projection 36b1 projecting from the tip of the bracket 36b (FIGS. 1 and 8), and the shaft 38b of the roller 38 is connected via a connecting chain 38c. Is connected to the shaft 36. Further, it is assumed that the concave groove 38a of the roller 38 corresponds to the movable blade S2.

The pressing devices 30 and 40 are respectively mounted on a movable frame 60 so as to be vertically movable as a whole. That is, on both side surfaces of the movable frame 60, guide blocks 67a, 67a,.
And a mounting base 6 having a central fixed block 67b.
7, 67 are formed (FIG. 3), and the pressing devices 30, 4
The zero guide rods 31a, 31a vertically penetrate the guide blocks 67a, 67a, respectively (FIG. 6). The rod 32a of the air cylinder 32 is connected to the upper end surface of the fixed block 67b. Therefore, when the air cylinder 32 expands and contracts, the pressing devices 30 and 40
Guide rods 31a, 31a are guide blocks 67a,
The base 31 moves up and down by being guided up and down by being guided by 67a, and can be moved up and down as a whole.

Before and after the fixed blade S1, the pressing devices 30, 4
0 is provided (FIGS. 2 and 3). The pressing devices 30, 40 corresponding to the fixed blade S1 have the same structure as the pressing devices 30, 40 corresponding to the movable blade S2, respectively, and the relative positional relationship with respect to the fixed blade S1 is different from that of the movable blade S1.
It is identical to that for 2. The pressing devices 30, 40 corresponding to the fixed blade S1
The guide blocks 57a, 57a,..., And the fixed block 57b are formed on the mounting bases 57 fixed to the
In the same manner as the pressing devices 30 and 40 corresponding to the movable blade S2, they are mounted on both sides of the fixed frame 50 so as to be vertically movable as a whole.

On the upstream side of the caterpillar device 10 on the upstream side, a mounting base 70a is protruded, and a ruler device 70 is disposed via the mounting base 70a (FIGS. 1 and 3). The ruler device 70 includes a ruler plate 71 that moves left and right along the upper surface of the caterpillar device 10, a screw shaft 72 that drives the ruler plate 71, and a feed motor 73 that drives the screw shaft 72 as main members. I have.

The ruler plate 71 is fixed to the upper surface of a box-shaped moving case 71b via an arm 71a, and guide rods 71c, 71c are arranged inside the moving case 71b. A screw bracket 71d is fixed inside the moving case 71b, and the screw shaft 72 is screwed to the screw bracket 71d. The screw shaft 72 is mounted on the bearing 7
2a, 72a and bearings 72a, 7
2a is fixed to the mounting base 70a via brackets 72b, 72b. Also, the guide rod 71c,
71c penetrates the brackets 72b, 72b slidably. However, the brackets 72b, 72b, the bearing 7
2a and 72a are arranged at both ends of the screw shaft 72 so as to sandwich the screw bracket 71d.

One end of the screw shaft 72 is connected to a drive chain 73a.
Is connected to the feed motor 73 via the. Then, when the feed motor 73 is driven, the screw bracket 71d is moved right and left via the screw shaft 72, and the screw bracket 71d is moved.
The ruler plate 71 can be moved to the left and right via the movable case 71b and the arm 71a integrated with d, and the ruler plate 71 can be positioned at an arbitrary position.

When the main motor M is operated, the movable blade S2 can be driven to rotate via the main shaft 63 (FIG. 5). On the other hand, the rotation of the main shaft 63 is controlled by the rotation of the inner race 52 of the spline bearing 52.
b, since it is also transmitted to the fixed blade S1 via the outer cylinder 63b, the fixed blade S1 and the movable blade S2 can be simultaneously driven to rotate in the same direction by the main motor M.

On the other hand, the screw shaft 53 is driven by the feed motor 53c.
Is rotated, the movable frame 60 is moved to the fixed frame 50.
You can move up and down on the top. Here, the main motor M
Is mounted on the movable frame 60, and the main shaft 63 is assembled integrally with the movable frame 60 via the bearing 63a. Therefore, the main shaft 63 slides on the spline bearing 52 in the axial direction, and therefore, the movable blade 60 S2 moves back and forth together with the movable frame 60. That is, the movable blade S2
Moves relative to the fixed blade S1 back and forth, and the distance between the two can be set arbitrarily. At this time, since the dust removal duct 66 corresponding to the movable blade S2 is mounted on the movable frame 60 via the legs 64, 64 and the auxiliary frame 65, the relative positional relationship between the dust removal duct 66 and the movable blade S2 is also large. Can be kept unchanged. The same applies to the pressing devices 30 and 40 corresponding to the movable blade S2.

The pressing devices 30, 30, 40, and 40 can be moved up and down by expanding and contracting the respective air cylinders 32. That is, when the air cylinder 32 is shortened, the whole is lowered, and the feed chains 35, 3
5, the rollers 37 and 38 of the pressing device 40 are in the operating position H
1 (FIG. 9) and the air cylinder 32
Is extended, the entire body rises, and the ascending position H2 can be taken.

When the air cylinder 33 is expanded and contracted, the bracket 36b swings up and down, and the feed chains 35, 3
.. Can take a horizontal posture in which the traveling angle is horizontal and an inclined posture in which the traveling angle is inclined upward toward the corresponding fixed blade S1 and movable blade S2. , The same height position and a position higher than it. Therefore, when the feed chains 35, 35,... Take a horizontal posture, the corresponding fixed blade S1 and movable blade S2
Are inserted into the concave grooves 35a1 of the chain guide 35a (FIG. 6). At this time, the cutting edges of the fixed blade S1 and the movable blade S2 are between the plural feed chains 35 at the distal end of the bracket 36b. And intersect with the feed chains 35, 35,. When the pressing device 30 is at the raised position H2 and the feed chains 35, 35 are inclined, the cutting edges of the fixed blade S1 and the movable blade S2 are free from the intersection with the feed chains 35, 35, and both are free. (Fig. 9).

The same applies to the pressing device 40. When the roller 38 is at the same height as the roller 37, the pressing device 40 adjusts the cutting edge of the corresponding fixed blade S1 and the movable blade S2 to the roller 3
8 (FIG. 8), the cutting edges of the fixed blade S1 and the movable blade S2 intersect with the roller 38.
When the roller 38 is set higher than the roller 37 with the rising position H2, the intersection between the two is eliminated (FIG. 9).

It should be noted that if the crossing of the pressing devices 30, 30, 40, 40 with the cutting edges of the fixed blade S1 and the movable blade S2 is eliminated,
The fixed blade S1 and the movable blade S2 can be easily replaced.

To grind the sawn wood W at two places, first, the ruler plate 71 is positioned at a predetermined position (FIG. 10A), and the movable frame 60 is moved to move the fixed blade S1 to the movable blade 60. The interval between the blades S2 is set appropriately. Next, the feed chains 35, 35... Of the pressing devices 30, 30 are set in a horizontal position, and the rollers 38, 38 of the pressing devices 40, 40 are set at the same height as the rollers 37, 37.
Place 0 and 40 at the ascending position H2 and wait.

Subsequently, the fixed blade S1 and the movable blade S2 are shown in FIG.
, The caterpillar devices 10 and 20 are driven in the directions of arrows K2 and K2 in FIG.
., And the rollers 38, 38, 37, 37 of the pressing devices 40, 40 are driven in the directions of arrows K3, K4, K4, respectively. However, the feed chains 35, 35, and the rollers 37, 38 can be driven by the motors 34, 34 of the pressing devices 30, 40, respectively, and the motors 34, 34 are driven by the traveling speeds of the feed chains 35, 35, respectively. , And the rollers 37 and 38 are electrically driven synchronously with the drive motor 15 so that the peripheral speed of the saw blades W matches the transport speed of the sawn wood W by the caterpillar devices 10 and 20.

The sawn wood W is moved along the ruler plate 71 by the arrow A in FIG.
When the tip of the sawn wood W has advanced to below the pressing devices 30, 30, the pressing devices 30, 30 are moved to the operating position H.
Lower to 1. Thereby, the feed chains 35, 35
... can press the upper surface of the sawn wood W to give a large conveying force to the sawn wood W.

When the ground material W is broken by the fixed blade S1 and the movable blade S2, and the tip thereof reaches below the pressing devices 40, 40, the pressing devices 40, 40 are lowered to the operating position H1. Thus, the rollers 38 and 37 can press the sawn material W and similarly apply a large conveying force. The pressing devices 30, 30, 40, and 40 are respectively returned to the ascending position H2 when the rear end of the sawn wood W passes, and the same procedure may be repeated thereafter.

The sawn lumber W is supplied to the caterpillar devices 10, 2
Even in the middle of 0, since the lower surface can be supported by the sawing material support surfaces 66a, 66a, 54a, 54a of the dust removing ducts 66, 54, even if the sawing material W is short, the posture is in the middle of its progress. Is very unlikely to be disturbed. In addition, the simultaneous cutting at the two positions can be performed by removing the nodal portion W1 of the sawn material W by appropriately setting the interval between the fixed blade S1 and the movable blade S2 (see FIG. 10A). ), And can be applied to both ears (FIG. (B)). Further, if only one of the fixed blade S1 and the movable blade S2 is used, a simple one-piece cutting can be performed (FIG. 3C).

Further, in the case where the thickness of the sawn wood W to be charged is substantially uniform, for example, the pressing devices 30, 30, 40, 40
Can be set and operated as follows.

First, in the standby state, the pressing device 30,
30 is set so that the lower surface of the feed chains 35, 35,... Is slightly lower than the upper surface of the sawn material W so that the sawn material W is automatically fed between the feed chains 35, 35,. I do. At this time, the travel angle of the feed chains 35, 35 ... via the air cylinder 33 may be slightly lowered toward the fixed blade S1 and the movable blade S2. On the other hand, the pressing devices 40, 40
The whole is lowered sufficiently so that the roller 8 is slightly lower than the roller 37 and the roller 38 is very close to the upper surface of the caterpillar device 20.

When the sawn wood W is loaded, the sawn wood W is automatically drawn into and conveyed between the feed chains 35, 35, and the caterpillar device 10. Then, the feed chains 35, 35,... Are pushed up by the sawn wood W, and the pressing devices 30,
Upon detecting that the air cylinders 33, 33 of the 30 have contracted, the pressing devices 40, 40 are raised, and the rollers 38, 38 are set to a height at which the sawn wood W can be automatically drawn in. When the tip of the sawn wood W reaches the position of the rollers 38, 38, the sawn wood W is drawn in by the rollers 38, 38,
After being conveyed by the rollers 38, 38, 37, 37 and the caterpillar device 20, the pressing devices 40, 40
When the trailing end of the sawn wood W passes through the position of the pressing devices 30 and 30, the extension of the air cylinders 33 and 33 is detected, and the original standby state is restored. At least the tip of the sawn wood W is a fixed blade S
1. At the time of contact with the movable blade S2, the rollers 38,
38 is sufficiently lowered, so that even if an extremely thin sawing material W is erroneously input, it is inadvertently pressed by the pressing devices 40, 40.
The danger of jumping out to the side can be reduced.

[0056]

As described above, according to the first aspect of the present invention, the fixed blade, the movable blade, the caterpillar device divided and disposed before and after the fixed blade and the movable blade, the fixed blade, By providing a pressing device disposed before and after each of the movable blades, the caterpillar device and the pressing device can provide a stable conveying force to the sawn timber, and are very close to the fixed blade and the movable blade. In this case, since the conveying force can be maintained, there is an excellent effect that even a short sawn timber can be efficiently and stably cut.

According to the second aspect of the present invention, the feed chain is provided with a bracket swingably mounted on the lower portion of the base and a plurality of feed chains running along the outer periphery of the bracket. Drives at the same running speed as the speed, and since the cutting edge of the circular saw blade can be housed at the tip of the bracket, it comes into uniform contact with the sawn timber, and the sawn timber extends over the entire length of the feed chain. In addition to providing a stable conveying force to the blade, the sawmill is supplied stably toward the cutting edge of the circular saw blade, is stably separated from the cutting edge of the circular saw blade, and the short sawmill is smoothly transported. There is an excellent effect that you can.

[Brief description of the drawings]

FIG. 1 Overall configuration diagram

FIG. 2 is a perspective view of a main part.

FIG. 3 is an exploded perspective view of a main part.

FIG. 4 is a longitudinal sectional view of a main part.

FIG. 5 is an explanatory diagram of a main part configuration.

FIG. 6 is an explanatory perspective view of a main part.

7 is a sectional view taken along line XX of FIG. 6;

FIG. 8 is an exploded perspective view of a main part.

FIG. 9 is an operation explanatory view (1).

FIG. 10 is an operation explanatory view (2).

[Explanation of symbols]

 W: sawn wood M: main motor S1: fixed blade S2: movable blade H1: operating position 10, 20: caterpillar device 30, 40: pressing device 31: base 35: feed chain 36b ... bracket 50: fixed frame 60: movable frame 63: spindle 63b: outer cylinder 54a, 66a: sawn wood support surface

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B27B 25/00-25/08

Claims (5)

(57) [Claims] A fixed frame, a movable frame mounted on the fixed frame so as to be movable back and forth, a main shaft mounted on the movable frame together with a main motor, and mounted on the fixed frame coaxially with the main shaft. An outer cylinder that is spline-coupled to a fixed blade attached to the tip of the outer cylinder; a movable blade attached to the tip of the main shaft; and a fixed blade that is divided and disposed before and after the movable blade. A circular sawing machine comprising: a caterpillar device according to (1), and a pressing device mounted on the fixed frame and the movable frame before and after each of the fixed blade and the movable blade. 2. The circular saw machine according to claim 1, wherein each of the pressing devices has an operating position intersecting with the corresponding cutting edge of the fixed blade and the movable blade. 3. The circular saw according to claim 1, wherein a ground material supporting surface having the same height as a conveying surface of the caterpillar device is provided below the fixed blade and the movable blade. Board. 4. A bracket mounted on a lower portion of a base so as to be swingable, and a plurality of feed chains running along an outer periphery of the common bracket, wherein the feed chain has a tip portion of the bracket. Wherein the cutting edge of the circular saw blade can be housed in between, and is driven at the same running speed as the transport speed of the sawn material, and the device for pressing a sawn material in a circular sawing machine. 5. The apparatus for pressing a sawn timber in a circular saw machine according to claim 4, wherein said bracket is swung up and down via an air cylinder.