JPS6234487B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a metalworking bandsaw used for cutting metal.
More specifically, it relates to a band saw that reduces vibration during sawing even if the shape and pitch of the saw teeth are the same, simply by changing the cutting width.

Conventionally, a band saw 1 for metalworking is disclosed in Japanese Patent Application Laid-Open No. 55-31598, and this saw blade has a tooth-shaped blade including a plurality of repeating groups of teeth, each group having the same shape. comprising a series of teeth which are alternately curved laterally by an amount and whose throat depth and pitch gradually decrease and then gradually increase in throat depth and pitch, the rake angle of said teeth being By having shorter teeth have a larger positive rake angle than longer teeth, the amount of material each saw tooth cuts into is reduced, thereby attenuating saw runout caused by set asymmetry. As a result, the uneven pattern that occurs when sawing material with a general band saw, as shown in Figure 2, is no longer recognized, and as a natural result, the cut surface becomes more accurate, the sawing allowance decreases, and the cutting speed increases. The cutting speed is faster, the cutting noise is lower, and the saw blade has a longer lifespan.

However, as mentioned above, the conventional band saw has various saw blades with different shapes and pitches, which not only makes it difficult and expensive to manufacture, but also makes it difficult to sharpen the saw blades even if they become hard to cut due to use. Because of the inability to do so, expensive band saws were now disposable.

The present invention was made in response to this current situation, and
By changing the setting width of an ordinary three-bladed band saw into multiple steps, the same function as the conventional band saw described above can be obtained, but since the shape and pitch of the saw blades are constant, sawing is easy and The purpose of the present invention is to provide a cutting saw that can be sharpened and used repeatedly when the saw teeth become dull.

Next, an embodiment of a band saw for metalworking according to the present invention will be explained based on the drawings.

In Figures 3 and 4 of the drawings, 2 is a band saw, on the front edge of which is formed a sawtooth a with a constant shape and pitch, and these sawtooths a are divided into a straight one a1 and a counterclockwise one a1.
2 and the one that swings to the right, a3, are set into a set of three clams, and the width of the clams in each set is set alternately to the narrow one w and the wide one w' as shown in Figure 4 of the drawing, and then cut with a band saw. When looking at 2 from the front, there is a1 with a straight sawtooth, a2 with a leftward swing, and a3 with a rightward swing.
However, due to the above-mentioned change in the opening width, drawing No. 5
As shown in the figure, b ₁ , b ₂ , b ₃ , b ₄ , b ₅ , b ₆ , b ₇ , b ₈ ,
It has nine cutting edges b ₉ or b ₁ , b ₂ , b ₃ , b ₄ , b ₅ , b ₆ , b ₇ , b ₈ , b ₉ , as shown in Figure 6 of the drawing.
b It has ₁₀ cutting edges,
Furthermore, if necessary, use two or more layers of clam width.
Although it is possible to change the number of stages to three or more, such as w' and w'', the drawings for this case are omitted.

7 to 11 of the drawings, reference numeral 3 indicates a grinding wheel for sharpening, which is disclosed in the patent application filed by the present inventor in 1983.
As in No. 95523 "Grinding device for metalworking saws", it is possible to convert the angle at which the grinding wheel 3 hits the saw teeth a to straight, leftward deflection, and rightward deflection. Using a device that can automatically convert the straight sawtooth a1 to the one shown in Figure 7 of the drawing, the sawtooth a2 and a3 with narrow left and right runout widths are struck as shown in Figure 8 of the drawing. As shown in Figures 10 and 11, for sawtooths a2 and a3 with wide left and right swing widths, each sawtooth with different angles hits as shown in Figures 10 and 11. This is to automatically polish a1, a2, and a3.

Since the metalworking band saw constructed as described above has the same shape and pitch of the saw teeth a, it can be easily manufactured using a normal saw machine, and cutting can be done by simply changing the width into multiple stages. Therefore, it can be easily done using a general machine, and the completed saw can be sharpened using a sharpening machine with an oblique grinding function to make the saw tooth a sharp and sharp. Moreover, since this band saw 2 has the setting width of each saw tooth a varied widely and narrowly, depending on the set setting of the setting width, there are nine cutting edges b ₁ to b ₉ as shown in Figure 5 of the drawing. , or as shown in Figure 6 of the drawing.
Since 10 of b ₁ to _{b 10} are obtained, the cutting of the material by this band saw 2 is performed piecewise with nine or ten cutting edges to reduce the depth of cut per tooth.
Therefore, the saw runout caused by the asymmetry of the cut is significantly attenuated, so when the saw runout is large, the wavy pattern that appears on the cut of the material as shown in Figure 2 no longer appears, and the cut surface In addition to improving the smoothness of the material, the cutting margin of the material by the band saw 2 (the part where the material becomes waste due to sawing) is reduced. Further, if the saw runout is reduced, the cutting speed of the saw is increased, cutting noise is reduced, and the tooth retention of the saw teeth a is improved.

The band saw for metalworking according to the present invention is a band saw with three sets of saw teeth of the same shape and pitch and set in straight, left-handed, and right-handed modes, and is subdivided into band saws by changing the setting width into multiple steps. Since we have obtained a cutting edge of Eliminate most of it. As a result, the cut surface becomes smooth, making subsequent finishing operations easier, and the cutting allowance is reduced, which saves material.Moreover, saw runout is attenuated, and the cutting speed of the saw is increased, making work easier. Efficiency is increased and cutting noise is reduced, which is effective for noise prevention, and it also reduces saw tooth wear and extends tooth life.

In addition, a band saw with three saw blades of the same shape and pitch, and a multi-stage setting width, can be manufactured at a low price like a general band saw.
Moreover, if you use a sharpening machine that can perform oblique angle grinding, automatic sharpening will be possible, which will improve the sharpness of new saws. It has the unique effect of being able to be used repeatedly until the blade runs out.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the smooth pattern of a cut surface made by an ordinary three-bladed band saw. FIG. 2 is a side view of a portion of an embodiment of a band saw for metalworking according to the present invention. Figure 3 is a plan view of the same as above. FIG. 4 and FIG. 5 are enlarged longitudinal sectional front views of main parts showing combinations of saw teeth with different set widths. FIGS. 6 to 10 are explanatory diagrams showing the state of polishing each saw tooth by the grinding wheel. In the figure, 2 is a band saw, a1, a2, and a3 are straight, left-handed, and right-handed saw teeth, and w and w' are set widths.

Claims (1)

[Claims] 1. A band saw for metalworking, characterized by a three-bladed band saw with saw teeth of the same shape and pitch set in straight, left-handed, and right-handed directions, and whose set width is varied in multiple stages.