JPH0269201A - Band saw for cold district - Google Patents

Abstract

PURPOSE:To eliminate the freezing trouble developing during winter season in cold district by a simple structure wherein raised teeth, the depth of each of which is larger than that of ordinary saw tooth, are made at the specified frequency and the set of the raised tooth is made to be the very small set slightly larger than the blade thickness of the saw concerned. CONSTITUTION:The band saw concerned 1 is an ordinary band saw made of band-like thin steel sheet having the saw width of about 100 - 255mm. The optimum pitch and depth of teeth 2 to be made is determined by various conditions such as the kind of trees, sawing width, efficiency of power source and the like. Raised teeth 3, 3..., the depth of each of which is special or higher than the depth of each of the standard teeth 2, 2... by about 0.1 - 1mm, are arranged among the standard teeth under the ideal distribution of one raised tooth in every three teeth. Further, the tooth form of the standard tooth 2 may well be made to have a swage set having a plectrum-like shape with a flat upper end edge point line or with a share point line, the upper end of which is obliquely cut alternately as scarf jointer.

Description

Detailed Description of the Invention (Object of the Invention) This invention relates to a band saw that is mainly used in sawmills located in cold regions such as Tohoku and Hokkaido. The purpose of the present invention is to provide a band saw with a new structure that can eliminate the problem of deformation of the band saw due to frictional heat caused by freezing of sawdust and adding frictional resistance to the band saw.

(Prior art) Speaking of sawmills, most of them have a building structure with an open border to the outside for the convenience of transporting lumber, and are located in cold regions such as Tohoku and Hokkaido. In many places, the work is grueling during the winter in cold temperatures that are almost the same as outside temperatures.

When sawing lumber in such an environment, if you use a regular bandsaw to proceed with the work, the surface of the lumber brought in will be frozen, making it difficult for the teeth to engage when cutting, making it difficult to find the exact location. This means that the engagement of the teeth on the band saw cannot be guaranteed, requiring great care when sawing to the exact dimensions.In addition, during the process of sawing, the sawdust that is generated can be damaged by the sawing lines or the band saw itself due to the cold. When it freezes, frictional resistance is applied to the bandsaw, generating frictional heat, which causes deformation of the bandsaw, resulting in a major defect in that the lumber is sawn with a lack of accuracy overall.

In addition, this resistance due to freezing weakens the strength of the band saw itself and reduces the sharpness and shelf life of the teeth. This is a challenge that many sawmills face during the winter months.

Up until now, no effective means of dealing with these phenomena have been found, so it has been necessary to change the band saw frequently and sharpen the saw each time, or to prevent rough cuts after sawing. Some companies even replace the band saw with a band saw with a much coarser tooth pitch, such as 40 mm or 50 m1, which is larger than the normal pitch (around 30 mm), knowing that this will result in severe damage. It is.

It is true that a bandsaw with coarse teeth not only has better grip on wood, but also reduces the amount of sawdust generated in proportion to the cube of the difference in pitch. This will make it easier to avoid the harmful effects of freezing, but on the other hand, as mentioned above, the cut end after sawing will be rough, and the resistance from the frozen wood will be the enemy. As the number of teeth decreases, the resistance applied to each tooth naturally increases, causing the teeth to wear out extremely quickly. This, in turn, causes a major drawback in that it imposes an excessive financial burden.

Under these circumstances, the development of a bandsaw that is effective for use during the winter in cold regions has been long-awaited, and as a result of extensive development and research, we have finally developed a band saw with the configuration detailed below. This was a successful development of an extremely effective band saw.

(Structure of the Invention) A band saw for use in cold regions according to the present invention shown in the drawings is basically a band saw having the following structure.

That is, the pitch of tiI2 is around 30 mm, the set is about 1.6 times the thickness of the plate, and the retraction size is almost the same as the pinch of a normal band saw 1. A standing tooth 3 with a tooth height of about 0.1 to 11 WwI is formed in about one out of three bandsaws 1 having ... This is a band saw for use in cold regions that is formed into slightly larger clams.

The band saw 1 is a normal band saw made of a thin steel plate with a saw width of about 100 to 255 mm, and its teeth 2 are designed to match the type of tree,
It is sufficient that the height of the teeth is determined by various conditions such as the grinding width and the performance of the power source. 3...
・Ideally, about one in three should be formed at a special height of about 0.1 to 1 degree higher.

In addition, the tooth profile of tooth 2, which serves as the reference, has an upper cutting edge line that is
As shown in the third country map, it is flat and shaped like a drumstick (or flat head) with an overall shape similar to a drumstick. It is also possible to have a tooth shape in which the upper end is formed into alternating diagonally cut cutting edge lines as shown in the figure. As can be understood from the enlarged part A shown in the third country drawing, the set 21.21 of the tooth 2, which serves as a reference, is the same as the plate thickness of the band saw 1, as is the case with commonly used band saws. It is formed over the side edges so that it spreads about 1.6 times as wide as the curve.

On the other hand, the standing tooth 3 is the set 21 of the tooth 2 described above.
Most of 21 has been shaved off, and as can be seen in the enlarged portion, the thickness of the plate has been reduced to the extent that it has expanded to the point of blood.

As shown in Drawing 2, the height of the standing tooth 3 is a shape that protrudes by 0.1 to 1 square inch from the imaginary line connecting the cutting edges of the tooth 2, which serves as a reference (dotted chain line). This state is shown in the cross-sectional view from A to A in Fig. 4 and from B to A in Fig. 5.
As shown in section B, they overlap in a straight line. In addition, standing tooth 3 for tooth 2 shown in each figure
The height is shown in a slightly exaggerated state in the figure.

(Function and Effect) The band saw for cold regions of the present invention having the above-described configuration has standard teeth 2, 2, and so on that are the same size as the 6 teeth of a commonly used band saw. Basically, we took care not to make the cut surface rough, and formed it so that about one out of every three teeth had standing teeth 3, and the burrs were almost small. Therefore, the standing teeth 3.3... take the lead in biting into the frozen timber surface.
In addition to enabling accurate cutting, this standing tooth 3.3・
Due to the formation of ..., the generation of saw dust can be reduced compared to that of a normal band saw, and the harmful effects caused by freezing of saw dust are minimized.

Also, what is particularly important is the standard tk2゜2...
The ratio of standing teeth 3, 3... to ... is 3
Since the ratio is limited to about one per book, the roughness of the cut, the bite condition, the generation of sawdust, the durability of the standing tooth 3, etc. are harmonized to almost ideal conditions. It is possible to form a band saw.

In other words, if the ratio of the standing teeth 3, 3, etc. to the standard teeth 2, 2, etc. is increased, the shelf life of the standing teeth 3 will certainly be improved, and the generated sawdust will be reduced. Although the amount will be reduced, the teeth that can really cut 2, 2...
If there is less ..., it will lead to the disadvantage that the cut will be rough and the efficiency of sawing will be lowered, and if there is less, the bite will be poor, and each standing tooth will be 3, 3...
The burden on ... increases, and the shelf life becomes worse.
Naturally, the leading effect will be weakened, and the amount of sawdust will be the same as usual, resulting in the problem of freezing.

As mentioned above, the product of this invention has an extremely simple structure that almost eliminates the harmful effects of frostbite that occurs during the winter in cold regions, guaranteeing accurate and efficient lumber production, and making it ideal for locations in such regions. The purpose of the present invention is to realize a band saw that can reliably reduce the burden on sawmills.

[Brief explanation of the drawing]

The drawings are based on representative embodiments of the present invention; FIG. 1 is a partial perspective view, FIG. 2 is a partial front view, and FIG. 3 is a partial plan view including an enlarged portion. , FIG. 4 is a sectional view taken along A-A, and FIG. 5 is a sectional view taken along B-B. ■... band saw, 2... tooth, 21... same clam, 3...
... Standing tooth, L...Virtual line. Figure λ

Claims (1)

[Claims] 1 The pitch of the teeth is around 30mm, and the clam is 1.6mm thick.
The pitch of a normal band saw is about twice that, and the height of the teeth is about 0.1 to 1 mm in about 1 out of 3 band saws that are the same size as a clam and have teeth shaped like a drumstick. This band saw for use in cold regions is formed by forming standing teeth with a high height, and forming the gap of the standing teeth into an extremely small gap that is slightly larger than the thickness of the board.