JP7519785B2 - Saw blade - Google Patents

Description

The present invention relates to a saw blade.

Patent Document 1 describes a saw blade in which cutting noise is suppressed.
The saw blade described in Patent Document 1 has a tooth tip pitch, which is the pitch of multiple teeth repeatedly formed as a set, that is different from each other. Also, in this saw blade, multiple set teeth that cut the same division width with respect to the full width of the cutting groove are repeatedly formed in a predetermined set pattern, and the tooth tip functional pitch, which is the pitch of the multiple teeth corresponding to each set pattern, is different from each other.
This saw blade is said to reduce cutting noise by suppressing resonance of cutting vibrations caused by the repetition of set patterns when cutting a workpiece.

JP 2009-233782 A

It is desirable to reduce cutting noise even more than the saw blade described in Patent Document 1.

Therefore, the problem that this invention aims to solve is to provide a saw blade that can further reduce cutting noise.

In order to solve the above problems, the present invention has the following configuration.
1) The sawtooth section has a repeating set of sawtooth teeth formed as sawtooth, the set of sawtooth teeth being arranged in a certain order, the set of sawtooth teeth being two straight teeth having a first function of cutting with a first cutting width, three left set teeth having a second function of cutting with a second cutting width, and three right set teeth having a third function of cutting with a third cutting width ;
The fixed order is, facing the opposite direction of the running direction during cutting, a straight tooth, a right set tooth, a left set tooth, a right set tooth, a straight tooth, a left set tooth, a right set tooth, a left set tooth,
The three left set teeth are a left set tooth functional set,
The three right set teeth are a right set tooth functional set,
The tooth tip pitches of adjacent left set teeth in the left set tooth functional set of one saw tooth set are defined as a first pitch and a second pitch from the front side in the traveling direction, and the tooth tip pitch between the rearmost left set tooth and the foremost left set tooth of the saw tooth set adjacent to the rear side of the one saw tooth set is defined as a third pitch,
When the tooth tip pitches of adjacent right set teeth in the right set tooth functional group of the one saw tooth group are defined as a fourth pitch and a fifth pitch from the front side in the traveling direction, and the tooth tip pitch between the rearmost right set tooth and the right set tooth furthest in the traveling direction in the saw tooth group adjacent to the rear side of the one saw tooth group is defined as a sixth pitch,
the first pitch, the second pitch, and the third pitch are different from one another and have a first magnitude relationship;
the fourth pitch, the fifth pitch, and the sixth pitch are different from one another according to a second magnitude relationship;
When the magnitude of the tooth tip area of the sawtooth is associated with the magnitude of the tooth tip mass set by the presence or absence of a protruding portion on the flank and the difference in the protruding amount when the protruding portion is present, or the presence or absence of a hollowed-out portion on the flank and the difference in the hollowed-out amount when the hollowed-out portion is present,
In each of the first pitch, the second pitch, and the third pitch, the magnitude relationship of the tooth tip areas of the left set tooth on the opposite side to the traveling direction coincides with the first magnitude relationship,
A saw blade in which the dimensional relationship of the tooth tip areas of the right set teeth on the opposite side to the traveling direction at each of the fourth pitch, the fifth pitch, and the sixth pitch coincides with the second dimensional relationship .
2) when the tooth tip pitch of the two straight teeth in the saw tooth set is defined as a seventh pitch, the tooth tip pitch of the straight tooth on the rear side and the straight tooth on the side furthest in the running direction in the saw tooth set adjacent to the rear side of one of the saw tooth sets is defined as an eighth pitch, and the magnitude relationship between the seventh pitch and the eighth pitch is defined as a third magnitude relationship,
The saw blade according to 1) , wherein, in each of the seventh pitch and the eighth pitch, the dimensional relationship of the tooth tip areas of the straight teeth on the opposite side to the traveling direction coincides with the third dimensional relationship.
3) The saw blade according to 1) or 2), wherein the saw blade is a band saw blade.

The present invention has the effect of further reducing cutting noise.

FIG. 1 is a partial side view showing a band saw blade 91A which is Example 1 of a saw blade according to an embodiment of the present invention. FIG. 2 is a bottom view of FIG. FIG. 3 is a schematic cross-sectional view showing cutting widths W1 to W3 when the band saw blade 91A forms the cutting groove Wm. FIG. 4 is a diagram illustrating the difference in the side shape of the saw teeth of the band saw blade 91A. FIG. 5 is a diagram showing the side shapes of sawtooths with different tooth tip areas, where (a) is a side view showing a sawtooth with a tooth tip area S, (b) is a side view showing a sawtooth with a tooth tip area M, and (c) is a side view showing a sawtooth with a tooth tip area L. FIG. 6 is a partial side view showing a band saw blade 91B which is Example 2 of the band saw blade according to an embodiment of the present invention. FIG. 7 is a bottom view of FIG. FIG. 8 is a diagram showing the side shapes of sawtooth showing examples of sawtooth having different tip areas. FIG. 9 is a diagram illustrating another example of sawtooth having different tip areas, illustrating differences in the side shapes of the sawtooth. 10A is a side view showing the shape of the sawtooth shown in FIG. 9, where (a) is a side view showing a sawtooth having a tooth tip area S, (b) is a side view showing a sawtooth having a tooth tip area M, and (c) is a side view showing a sawtooth having a tooth tip area L. FIG. 11 is a graph showing the relationship between the saw blade speed during cutting and the sound pressure level of the generated sound in Examples 1 and 2 and Comparative Examples 1 and 2.

Examples of saw blades according to the present invention will be described using saw blades 91A and 91B of Examples 1 and 2. Since the saw blades 91A and 91B are band saw blades, they will be referred to as band saw blades 91A and 91B, respectively, hereinafter.
Example 1
A band saw blade 91A according to a first embodiment will be described with reference to Figures 1 and 2. Figure 1 is a partial side view of the band saw blade 91A, and Figure 2 is a bottom view of the band saw blade 91A.

As shown in FIG. 1, a band saw blade 91A has a band-shaped body portion 1 and a sawtooth portion 2A formed on one edge of the body portion 1.
The sawtooth portion 2A is configured by a sawtooth set G1, which is a set of multiple teeth, repeatedly formed in the longitudinal direction of the body portion 1. In this example, the sawtooth portion 2A has N sawtooth sets G1-1, G1-2, ..., G1-N (N is a positive integer of 3 or more).

1 and 2, the sawtooth set G1 has eight sawtooth members, namely, straight teeth C11 and C12 as a straight tooth functional set CG, left set teeth L11, L12, and L13 as a left set tooth functional set LG, and right set teeth R11, R12, and R13 as a right set tooth functional set RG. The straight tooth functional set CG, the left set tooth functional set LG, and the right set tooth functional set RG are collectively referred to as the sawtooth functional set.
The arrangement order of the eight saw teeth in saw tooth set G1 is as follows: straight tooth C11 is used as reference A, and they face in the opposite direction to the traveling direction DRa during cutting, as follows: straight tooth C11, right set tooth R11, left set tooth L11, right set tooth R12, straight tooth C12, left set tooth L12, right set tooth R13, left set tooth L13.

FIG. 3 is a schematic cross-sectional view showing the cutting width allocated when the band saw blade 91A cuts the workpiece WP to form the cut groove Wm.
3, with respect to the total width Wa of the cutting groove Wm, the straight tooth functional group CG is responsible for cutting the cutting width W1 indicated by the straight tooth C11. The left set tooth functional group is responsible for cutting the cutting width W3 indicated by the left set tooth L12. The right set tooth functional group is responsible for cutting the cutting width W2 indicated by the right set tooth R12.

As shown in FIGS. 1 and 2, in the sawtooth set G1, the tooth tip pitch, which is the distance between the tips of adjacent teeth in the running direction DRa, is set so that four consecutive tooth tip pitches P11, P12, P13, and P14 form one tooth tip pitch pattern PT1, and this tooth tip pitch pattern PT1 is repeated.
In the band saw blade 91A, the four tooth tip pitches P11 to P14 are different from one another. Specific dimension examples of the tooth tip pitches P11 to P14 are as follows.
Tooth pitch P11: 8.3 mm
Tooth pitch P12: 6.9 mm
Tooth pitch P13: 6.2 mm
Tooth pitch P14: 7.6 mm

In more detail, the tooth tip pitch P11 is set to the tooth tip pitch between the straight tooth C11 and the right set tooth R11, and between the straight tooth C12 and the left set tooth L12. The tooth tip pitch P12 is set to the tooth tip pitch between the right set tooth R11 and the left set tooth L11, and between the left set tooth L12 and the right set tooth R13. The tooth tip pitch P13 is set to the tooth tip pitch between the left set tooth L11 and the right set tooth R12, and between the right set tooth R13 and the left set tooth L13. The tooth tip pitch P14 is set to the tooth tip pitch between the right set tooth R12 and the straight tooth C12, and between the left set tooth L13 and the leading straight tooth C11 in the next sawtooth set G1-2.

The eight sawtooths of the sawtooth set G1 are classified into three groups of teeth with different functions according to the cutting width that is assigned to the entire width of the cutting groove.
The three types of teeth groups are a straight teeth functional set CG, a left set teeth functional set LG, and a right set teeth functional set RG. The straight teeth functional set CG is made up of straight teeth C11 and C12, the left set teeth functional set LG is made up of left set teeth L11 to L13, and the right set teeth functional set RG is made up of right set teeth R11 to R13.

The pitch of multiple saw teeth classified according to the same function is called a tooth tip function pitch.
In the band saw blade 91A, a straight tooth tip function pitch is set as the tooth tip function pitch corresponding to the straight tooth functional group CG, a right set tooth tip function pitch is set as the tooth tip function pitch corresponding to the right set tooth functional group, and a left set tooth tip function pitch is set as the tooth tip function pitch corresponding to the left set tooth functional group.

Specifically, the tooth tip pitch of the multiple saw teeth that make up the straight tooth functional group CG is called the straight tooth tip function pitch, and as shown in Figures 1 and 2, in the band saw blade 91A, the straight tooth tip function pitch for the straight teeth C11 and C12 of the straight tooth functional group CG is one type, the straight tooth tip function pitch KPC11. The straight tooth tip function pitch KPC11 is the sum of the tooth tip pitches P11 to P14.
When the above-mentioned dimension example is applied to the tooth tip pitches P11 to P14,
KPC11=P11+P12+P13+P14=8.3mm+6.9mm+6.2mm+7.6mm=29mm
It is.

The tooth tip pitch of the multiple saw teeth that make up the left set tooth functional group LG is referred to as the left set tooth tip functional pitch, and as shown in Figures 1 and 2, the left set tooth tip functional pitches of the left set teeth L11 to L13 of the left set tooth functional group are of three types, left set tooth tip functional pitches KPL11 to KPL13.
The left set tooth tip functional pitch KPL11 is the sum of the tooth tip pitches P12 and P13.
The left set tooth tip functional pitch KPL12 is the sum of the tooth tip pitches P14, P11, and P12. The left set tooth tip functional pitch KPL13 is the sum of the tooth tip pitches P13, P14, and P11.
When the above-mentioned dimension example is applied to the tooth tip pitches P11 to P14,
KPL11=P12+P13=6.9mm+6.2mm=13.1mm
KPL12=P11+P12+P14=8.3mm+6.9mm+7.6mm=22.8mm
KPL13=P11+P13+P14=8.3mm+6.2mm+7.6mm=22.1mm
KPL11<KPL13<KPL12... (Formula 1)
It is.

If the tooth tip pitch of the multiple saw teeth that make up the right set tooth functional group RG is referred to as the right set tooth tip functional pitch, the right set tooth tip functional pitches of the right set teeth R11 to R13 in the right set tooth functional group are of three types, namely right tip functional pitches KPR11 to KPR13.
Specifically, the right set tooth tip function pitch KPR11 is the sum of the tooth tip pitches P12 and P13. The right set tooth tip function pitch KPR12 is the sum of the tooth tip pitches P14, P11 and P12. The right set tooth tip function pitch KPR13 is the sum of the tooth tip pitches P13, P14 and P11.

As is clear from the above, in the band saw blade 91A, the left set tooth tip functional pitch KPL11 and the right set tooth tip functional pitch KPR11 are equal, and the left set tooth tip functional pitch KPL12 and the right set tooth tip functional pitch KPR12 are equal.
That is,
KPR11=P12+P13=6.9mm+6.2mm=13.1mm
KPR12=P11+P12+P14=8.3mm+6.9mm+7.6mm=22.8mm
KPR13=P11+P13+P14=8.3mm+6.2mm+7.6mm=22.1mm
KPR11<KPR13<KPR12... (Formula 2)
It is.

The band saw blade 91A is determined so that the outer shape of the saw blade is classified into different sizes of tooth tip areas according to the groups of teeth with different functions to which they belong. In this example, the tooth tip areas are classified into three types, S, M, and L, in order from smallest to largest.
The tooth tip area is the area of the portion of the sawtooth from the tooth bottom position to the tip side in a side view.
In the sawtooth portion 2A of the band saw blade 91, the tooth root positions of all the saw teeth are on a tooth root line LN that is parallel to the edge of the body portion 1 as shown in FIG.
In FIG. 1, the sawtooths having a tooth tip area L are cross-hatched, the sawtooths having a tooth tip area M are hatched, and the sawtooths having a tooth tip area S are left unshaded to distinguish them from one another.

For example, in FIG. 1, the size of the tooth tip area of each of the right set teeth R11, R12, and R13 included in the right set tooth functional group RG is determined according to the size of the right set tooth tip functional pitch between the adjacent right set teeth on the running direction DRa side.

In detail, if the relationship of the tooth tip areas is as described above as tooth tip area S < tooth tip area M < tooth tip area L, then based on the relationship of (Equation 2),
The tooth tip area of the right set tooth R12 whose right set tooth tip functional pitch on the traveling direction DRa side is the minimum right set tooth tip functional pitch KPR11 is defined as the minimum tooth tip area S.
The tooth tip area of the right set tooth R11, whose right set tooth tip functional pitch on the traveling direction DRa side is the intermediate right set tooth tip functional pitch KPR13 among the three, is defined as the intermediate tooth tip area M.
The tooth tip area of the right set tooth R13, whose right set tooth tip functional pitch on the traveling direction DRa side is the maximum right set tooth tip functional pitch KPR12, is defined as the maximum tooth tip area L.

As shown in FIG. 4, in the first embodiment, the difference between the tooth tip areas S, M, and L of the saw tooth T1 is set with the rake angle θa and the clearance angle θb in common, and is set by whether or not a protrusion T1b is provided on the clearance face T1a, and by the amount of protrusion if a protrusion T1b is provided.
Specifically, the tooth tip area when no protrusion T1b is provided (solid line) is defined as tooth tip area S. If the tooth tip area when the protrusion T1b is provided with a first protrusion height is defined as tooth tip area M, the tooth tip area when the protrusion T1b is provided with a second protrusion height higher than the first protrusion height is defined as tooth tip area L.

As a result, as shown in FIG. 5, three types of sawtooth shapes having different tooth tip areas are set by different protruding shapes of the flank T1a.
FIG. 5A shows a sawtooth shape having a tooth tip area S, which corresponds to, for example, a straight tooth C11 as shown in FIG.
FIG. 5B shows a sawtooth shape having a tooth tip area M, which corresponds to, for example, the right set tooth R11 as shown in FIG.
FIG. 5C shows a sawtooth shape having a tooth tip area L, which corresponds to, for example, the left set tooth L11 as shown in FIG.

As described above, if the function of each saw tooth in the saw tooth portion 2A of the band saw blade 91A is classified by the division width, which is the cutting width allocated to each saw tooth relative to the total width of the cutting groove formed by cutting, the band saw blade 91A can be classified into three types: straight teeth C11, C12, C13, right set teeth R11, R12, R13, and left set teeth L11, L12, L13.
Generally, when cutting with a band saw blade, a fundamental tone and its overtones at a frequency corresponding to the repeating pattern, which is the arrangement of the sawtooth for each function, are generated as sounds, which are heard by workers and others as cutting noise.

The band saw blade 91A has left set tooth tip functional pitches KPL11 to KPL13 corresponding to the left set teeth which are different values as shown in (Equation 1), and right set tooth tip functional pitches KPR11 to KPR13 corresponding to the right set teeth which are different values as shown in (Equation 2).
As a result, the frequencies of the sounds of each saw tooth generated from the right set teeth R11 to R13 and the left set teeth L11 to L13 during cutting are dispersed rather than concentrated, suppressing the occurrence of resonance and reducing the sound pressure of the resonance frequency when resonance occurs due to cutting conditions such as the cutting speed.

Furthermore, as described above, the band saw blade 91A has a plurality of saw teeth with the same function, each of which has a different tooth tip area depending on the tooth tip functional pitch on the traveling direction DRa side.
The frequency of sounds generated by sawtooths with the same function during cutting is affected not only by the above-mentioned right set tooth tip functional pitch and left set tooth tip functional pitch, but also by the tooth tip mass of the sawtooth.
Specifically, a sawtooth with a large tooth tip mass produces a lower frequency sound during cutting than a sawtooth with a small tooth tip mass.

Therefore, as described above, the band saw blade 91A has a plurality of saw teeth with the same function, and the tooth tip area corresponding to the tooth tip mass is made to vary depending on the tooth tip functional pitch on the running direction side. For example, the right set tooth R12, which has the smallest right set tooth tip functional pitch KPR11 on the running direction DRa side, is formed with the smallest tooth tip area S.
As a result, the right set tooth R12 has the smallest right set tooth tip functional pitch KPR11, so that the frequency of the sound generated during cutting is higher than that of saw teeth with other right set tooth tip functional pitches. In addition, the right set tooth R12 has the smallest tooth tip area S, i.e., the smallest tooth tip mass, so the frequency of the sound generated during cutting is shifted even higher.

On the other hand, the right set tooth R13, which has the maximum right set tooth tip functional pitch KPR12 which is the pitch on the traveling direction DRa side, is formed with the maximum tooth tip area L.
As a result, the right set tooth R13 has the largest right set tooth tip functional pitch KPR12, so that the frequency of the sound generated during cutting is lower than that of saw teeth with other right set tooth tip functional pitches. In addition, the right set tooth R13 has the largest tooth tip area L, i.e., the largest tooth tip mass, so the frequency of the sound generated during cutting is shifted even lower.

From this, during cutting, the difference in frequency of the sound generated by the right set tooth R11 having the medium tooth tip area M becomes large, and the difference in frequency of the sound generated by the right set tooth R12 and the difference in frequency of the sound generated by the right set tooth R13 become large, respectively.
In other words, with the band saw blade 91A, the sound frequencies generated by each of the right set teeth R11 to R13 during cutting are dispersed farther apart from each other, thereby further suppressing the occurrence of resonance and further reducing the sound pressure of the resonant frequency when resonance occurs due to cutting conditions such as the cutting speed.

The tooth tip mass depends on the tooth tip area because the material and thickness of the tooth tip of each saw tooth can be considered to be roughly homogeneous and uniform.

The effects of the right set teeth functional set described above can be obtained similarly for the left set teeth L11 to L13 which are the left set teeth functional set.
That is, the left set tooth L13 having the minimum left set tooth tip functional pitch KPL11 on the traveling direction DRa side is formed with the minimum tooth tip area S.
As a result, the left set tooth L13 has the smallest left set tooth tip functional pitch KPL11, so that the frequency of the sound generated during cutting is higher than that of saw teeth with other left set tooth tip functional pitches. In addition, the left set tooth L13 has the smallest tooth tip area S, i.e., the smallest tooth tip mass, so the frequency of the sound generated during cutting is shifted to a higher frequency.

On the other hand, the left set tooth L11, whose maximum left set tooth tip functional pitch KPL12 is the pitch on the traveling direction DRa side, is formed with the maximum tooth tip area L.
As a result, since the left set tooth L11 has the largest left set tooth tip functional pitch KPL12, the frequency of the sound generated during cutting is lower than that of saw teeth with other left set tooth tip functional pitches. In addition, the left set tooth L11 has the largest tooth tip area L, i.e., the largest tooth tip mass, so the frequency of the sound generated during cutting is shifted even lower.

From this, during cutting, the difference in frequency of the sound generated by the left set tooth L12 having the medium tooth tip area M becomes large, and the difference in frequency of the sound generated by the left set tooth L13 and the difference in frequency of the sound generated by the left set tooth L11 become large, respectively.
In other words, with the band saw blade 91A, the sound frequencies generated by each of the left set teeth L11 to L13 during cutting are dispersed farther apart from each other, thereby further suppressing the occurrence of resonance and further reducing the sound pressure of the resonant frequency when resonance occurs due to cutting conditions such as the cutting speed.

For the straight tooth functional group CG, the straight tooth tip functional pitch KPC11 is constant, so the straight teeth C11 and C12 are formed with the same tooth tip area. In this example, the tooth tip area is set to the minimum tooth tip area S, and is configured to shift to the high-pitched side within the audible band, which is less likely to be perceived as noise at high cutting speeds due to the sensitivity characteristics of the hearing.

As described above, the band saw blade 91A determines the size of the tooth tip area of each of multiple saw teeth with the same function based on the size of the tooth tip functional pitch of the multiple saw teeth. This further reduces cutting noise with the band saw blade 91A.

Example 2
A band saw blade 91B according to a second embodiment will be described with reference to Figures 6 and 7. Figure 6 is a partial side view of the band saw blade 91B, and Figure 7 is a bottom view of the band saw blade 91B.

Band saw blade 91B differs from band saw blade 91A in the following two respects. First, band saw blade 91A has four consecutive tooth tip pitches configured as one tooth tip pitch pattern, whereas band saw blade 91B has eight consecutive tooth tip pitches configured as one tooth tip pitch pattern. Second, there are two types of straight tooth tip area.

As shown in FIG. 6, a band saw blade 91B has a band-shaped body portion 1 and a sawtooth portion 2B formed on one edge of the body portion 1.
The sawtooth portion 2B is configured by repeatedly forming a plurality of sawtooth sets G2, which are sets of teeth, in the longitudinal direction of the body portion 1.

As shown in Figures 6 and 7, the sawtooth set G2 has eight saw teeth, including straight teeth C21, C22, left set teeth L21, L22, L23, and right set teeth R21, R22, R23.
The arrangement order of the eight saw teeth in saw tooth set G2 is as follows: straight tooth C21 is used as reference A, and they face in the opposite direction to the traveling direction DRa during cutting, in the order of straight tooth C21, right set tooth R21, left set tooth L21, right set tooth R22, straight tooth C22, left set tooth L22, right set tooth R23, and left set tooth L23.

In addition, in the sawtooth set G2, the tooth tip pitch, which is the distance between the tips of adjacent teeth in the running direction DRa, is set so that eight consecutive tooth tip pitches P21, P22, P23, P24, P25, P26, P27, and P28 form one tooth tip pitch pattern, and this tooth tip pitch pattern PT2 is repeated.
In the band saw blade 91B, among the eight tooth tip pitches P21 to P28, the tooth tip pitches P21 to P24 and the tooth tip pitches P25 to P28 are associated such that the tooth tip pitch P24, which is the tooth tip pitch on the running side of the straight teeth C21 and C22, is different from the tooth tip pitch P28, and the tooth tip pitches P21 to P23 are the same as the tooth tip pitches P25 to P28. Specific dimensional examples of the tooth tip pitches P21 to P28 are as follows.
Tooth pitch P21: 8.3 mm
Tooth pitch P22: 6.9 mm
Tooth pitch P23: 6.2 mm
Tooth pitch P24: 7.6 mm
Tooth pitch P25: 8.3 mm
Tooth pitch P26: 6.9 mm
Tooth pitch P27: 6.2 mm
Tooth pitch P28: 7.0 mm

In more detail, the tooth tip pitch P21 is set between the straight tooth C21 and the right set tooth R21, and between the straight tooth C22 and the left set tooth L22. The tooth tip pitch P22 is set between the right set tooth R21 and the left set tooth L21, and between the left set tooth L22 and the right set tooth R23. The tooth tip pitch P23 is set to the pitch between the left set tooth L21 and the right set tooth R22, and between the right set tooth R23 and the left set tooth L23.

The eight sawtooths of the sawtooth set G2 are classified according to their functions based on the cutting widths that are allocated to the overall width of the cutting groove. More specifically, the sawtooth set G2 is classified into three types of tooth groups with different functions.
The three groups of teeth are a straight teeth functional set CG, a left set teeth functional set LG, and a right set teeth functional set RG. The straight teeth functional set CG is made up of straight teeth C21 and C22, the left set teeth functional set LG is made up of left set teeth L21-L23, and the right set teeth functional set RG is made up of right set teeth R21-R23.

The pitch of multiple sawtooths having the same function is called a tooth tip function pitch.
In the band saw blade 91B, a straight tooth tip functional pitch corresponding to the straight tooth functional group CG, a right set tooth tip functional pitch corresponding to the right set tooth functional group RG, and a left set tooth tip functional pitch corresponding to the left set tooth functional group LG are set.

The tooth tip pitch of the multiple saw teeth that make up the straight tooth functional group CG is called the straight tooth tip function pitch, and as shown in Figures 6 and 7, in the band saw blade 91B, the straight tooth tip function pitches for the straight teeth C21, C22 of the straight tooth functional group CG are of two types: straight tooth tip function pitch KPC21 and straight tooth tip function pitch KPC22.
As shown in Figures 6 and 7, the straight tooth tip functional pitch KPC21 is the sum of the tooth tip pitches P21 to P24, and the straight tooth tip functional pitch KPC22 is the sum of the tooth tip pitches P25 to P28.
When the above-mentioned dimension example is applied to the tooth tip pitches P21 to P28,
KPC21=P21+P22+P23+P24=8.3mm+6.9mm+6.2mm+7.6mm=29mm
KPC22=P25+P26+P27+P28=8.3mm+6.9mm+6.2mm+7.0mm=28.4mm
KPC22<KPC21... (Formula 3)
It is.

The tooth tip pitch of the multiple saw teeth that make up the left set tooth functional group LG is referred to as the left set tooth tip functional pitch, and as shown in Figures 6 and 7, the left set tooth tip functional pitches of the left set tooth functional groups L21 to L23 are of three types, left set tooth tip functional pitches KPL21 to KPL23.
The left set tooth tip functional pitch KPL21 is the sum of the tooth tip pitches P22 and P23.
The left set tooth tip functional pitch KPL22 is the sum of the tooth tip pitches P24, P25, and P26. The left set tooth tip functional pitch KPL23 is the sum of the tooth tip pitches P27, P28, and P21.
When the above-mentioned dimension example is applied to the tooth tip pitches P21 to P28,
KPL21=P22+P23=6.9mm+6.2mm=13.1mm
KPL22=P24+P25+P26=7.6mm+8.3mm+6.9mm=22.8mm
KPL23=P27+P28+P21=6.2mm+7.0mm+8.3mm=21.5mm
KPL21<KPL23<KPL22... (Formula 4)
It is.

The tooth tip pitch of the multiple saw teeth that make up the right set tooth functional group RG is referred to as the right set tooth tip functional pitch, and as shown in Figures 6 and 7, the right set tooth tip functional pitches of the right set teeth R21 to R23 of the right set tooth functional group RG are of three types, namely right set tooth tip functional pitches KPR21 to KPR23.
The right set tooth tip function pitch KPR21 is the sum of the tooth tip pitches P22 and P23. The left set tooth tip function pitch KPR22 is the sum of the tooth tip pitches P24, P25, and P26. The left set tooth tip function pitch KPR23 is the sum of the tooth tip pitches P27, P28, and P21.
When the above-mentioned dimension example is applied to the tooth tip pitches P21 to P28,
KPR21=P22+P23=6.9mm+6.2mm=13.1mm
KPR22=P24+P25+P26=7.6mm+8.3mm+6.9mm=22.8mm
KPR23=P27+P28+P21=6.2mm+7.06mm+8.3mm=21.5mm
KPR21<KPR23<KPR22... (Formula 5)
It is.

The band saw blade 91B is designed so that the outer shape of the saw blade is classified into a plurality of different sizes of tooth tip areas according to the groups of teeth with different functions to which the respective shapes belong. In this example, the tooth tip areas are of three types, S, M, and L, from smallest to largest.
In FIG. 6, the sawtooth having a tooth tip area L is cross-hatched, the sawtooth having a tooth tip area M is hatched, and the sawtooth having a tooth tip area S is left blank to distinguish them.

The difference in tooth tip area in the band saw blade 91B is set by the presence or absence of a protrusion T1b on the clearance surface T1a, and by the difference in the protrusion height if a protrusion T1b is present, while keeping the rake angle θa and clearance angle θb the same, as in the case of the band saw blade 91A in Example 1.

For example, in FIG. 6, the size of the tooth tip area of each of the right set teeth R22, R23, and R24 included in the right set tooth functional group RG is determined according to the size of the right set tooth tip functional pitch between the adjacent right set teeth on the traveling direction DRa side.

The relationship of the tooth tip areas is S<M<L, so
Based on the above-mentioned relationship of KPR21<KPR23<KPR22,
The right set tooth R22 whose right set tooth tip functional pitch on the traveling direction DRa side is the minimum right set tooth tip functional pitch KPR21 has the minimum tooth tip area S.
The right set tooth R21 having a right set tooth tip functional pitch on the traveling direction DRa side that is the intermediate right set tooth tip functional pitch KPR23 has an intermediate tooth tip area M.
The right set tooth R23, whose right set tooth tip functional pitch on the traveling direction DRa side is the maximum right set tooth tip functional pitch KPR22, has the maximum tooth tip area L.

Also, as shown in Figure 6, in the band saw blade 91B, the size of the tooth tip area of each of the straight teeth C21, C22 included in the straight tooth functional group CG is determined according to the size of the straight tooth tip functional pitch between the adjacent straight teeth on the traveling direction DRa side.
The relationship between the tooth tip areas is S < L, so
Based on the relationship KPC22<KPC21, which is the above-mentioned (Equation 3),
The tooth tip area of the straight tooth C21 whose straight tooth tip functional pitch on the traveling direction DRa side is the smaller straight tooth tip functional pitch KPC22 is defined as tooth tip area S, and the tooth tip area of the straight tooth C22 whose straight tooth tip functional pitch on the traveling direction DRa side is the larger straight tooth tip functional pitch KPC21 is defined as tooth tip area L.
As a result, during cutting, the sound frequencies generated by the straight teeth C21 and the sound frequencies generated by the straight teeth C22 are dispersed rather than concentrated, suppressing the occurrence of resonance and further reducing the sound pressure of the resonant frequency when resonance occurs due to cutting conditions such as the cutting speed.
In this example, during cutting, the frequency of the sound generated by the straight teeth C21 shifts to a higher frequency, and the frequency of the sound generated by the straight teeth C22 shifts to a lower frequency and is dispersed.

In the right set tooth functional group RG, the right set tooth R22 having the minimum right set tooth tip functional pitch KPR21 which is the pitch on the traveling direction DRa side is formed with the minimum tooth tip area S.
As a result, since the right set tooth R22 has the smallest right set tooth tip functional pitch KPR21, the frequency of the sound generated during cutting is higher than that of saw blades with other right set tooth tip functional pitches. In addition, the right set tooth R22 has the smallest tooth tip area S, i.e., the smallest tooth tip mass, so the frequency of the sound generated during cutting is shifted even higher.

On the other hand, the right set tooth R23, whose maximum right set tooth tip functional pitch KPR22 is the pitch on the traveling direction DRa side, is formed with the maximum tooth tip area L.
As a result, the right set tooth R23 has the largest right set tooth tip functional pitch KPR22, so that the frequency of the sound generated during cutting is lower than that of saw teeth with other right set tooth tip functional pitches. In addition, the right set tooth R23 has the largest tooth tip area L, i.e., the largest tooth tip mass, so that the frequency of the sound generated during cutting is shifted to a lower level.

Therefore, when cutting, the difference in sound frequency generated by the right set tooth R21 having the medium tooth tip area M, and the difference in sound frequency generated by the right set tooth R22, and the difference in sound frequency generated by the right set tooth R23, are each large.
The same is true for the left set tooth functional group LG, and when cutting, the difference in sound frequency generated by the left set tooth L22 having the medium tooth tip area M becomes large compared to the sound frequency generated by the left set tooth L21 and the sound frequency generated by the left set tooth L23.
Furthermore, the band saw blade 91B also distributes the sound frequencies generated by the straight teeth C21 and the straight teeth C22 during cutting in the straight tooth functional group CG so that they are different from each other.
As a result, when cutting, the sound frequencies generated by each of the saw teeth of the right set teeth R21-R23, the left set teeth L21-L23, and the straight teeth C21, 21 of the band saw blade 91B are dispersed rather than concentrated, thereby further suppressing the occurrence of resonance and further reducing the sound pressure of the resonance frequency when resonance occurs due to cutting conditions such as the cutting speed.

As a method for obtaining sawtooths with different tooth tip areas, differences in tooth bottom positions may be utilized as shown in FIG.
For example, the position of the tooth bottom is set on either the tooth bottom line LN1 or the tooth bottom line LN2 which is located deeper than the tooth bottom line LN1.
Specifically, the tooth bottoms of the saw teeth T1 and T2 are set as the tooth tooth T1 whose rake side and clearance side are both on the tooth root line LN1, the tooth tooth T2 whose rake side is on the tooth root line LN2 and the clearance side is on the tooth root line LN2, and the tooth bottoms of the saw teeth T3 and T4 whose rake side is on the tooth root line LN1 and the clearance side is on the tooth root line LN2, and the tooth tooth T4 whose rake side and clearance side are on the same tooth root line LN2.
According to this method, it is possible to form four saw teeth with different tooth tip areas: tooth tip area S of saw tooth T1, tooth tip area M- of saw tooth T2, tooth tip area M+ of saw tooth T3, and tooth tip area L of saw tooth T4, in order from the smallest tooth tip area.

As another method for obtaining sawtooths with different tooth tip areas, the presence or absence of a carved portion T1c on the flank T1a of the sawtooth, and the difference in the amount of carving when the carved portion T1c is present, may be utilized, as shown in Figures 9 and 10.
As shown in FIG. 9, in the sawtooth, the rake angle θa and the clearance angle θb are common, and the difference in tooth tip area is set depending on whether or not a carved portion T1c is provided on the clearance face T1a and, if a carved portion T1c is provided, the amount of carving.
Specifically, as shown in Fig. 10(a), the tooth tip area of the sawtooth T5 having the deepest recessed portion T1c is defined as tooth tip area S. As shown in Fig. 10(b), the tooth tip area of the sawtooth T6 having a shallower recessed portion T1c than the sawtooth T5 is defined as tooth tip area M. As shown in Fig. 10(c), the tooth tip area of the sawtooth T7 having no recessed portion T1c is defined as tooth tip area L.

11 is a graph showing the relationship between saw blade speed and sound pressure level of sound generated during cutting, for four types of test band saw blades: band saw blade 91A of Example 1, band saw blade 91B of Example 2, band saw blade 101 of Comparative Example 1, and band saw blade 102 of Comparative Example 2. The sound generated during cutting is substantially heard by the operator as noise.
The sound pressure measurements were performed using a sound level meter, NL-42 manufactured by RION Co., Ltd., under the same measurement conditions for all the test band saw blades. The maximum value of the A-weighted sound pressure was plotted on the graph.

The band saw blade 101 of Comparative Example 1 has the same sawtooth arrangement and tooth tip pitch pattern as the band saw blade 91A, but the sawtooth portions are formed so that the tooth tip areas are simply alternatingly larger and smaller regardless of the function of the sawtooth.
The band saw blade 102 of Comparative Example 2 is different from the band saw blade 101 in that all the saw teeth are formed with the same tooth tip area.

As is clear from Fig. 11, the sound pressure level of the band saw blades 91A and 91B of Examples 1 and 2 is lower at all saw blade speeds than that of Comparative Examples 1 and 2, and the effect of reducing noise by setting the tooth tip area according to the tooth tip functional pitch is recognized. The sound pressure level of the band saw blades 91A and 91B of Examples 1 and 2 is about 5 dB lower than that of Comparative Examples 1 and 2.
The band saw blade 91B of Example 2 has a lower sound pressure level than the band saw blade 91A of Example 1, and it is recognized that noise is further reduced.

The embodiment of the present invention is not limited to the above-mentioned configuration, and may be modified without departing from the spirit of the present invention.

In the band saw blades 91A and 91B of the first and second embodiments, the sawtooth portion is classified into three types of functions, namely, a straight tooth and left and right set teeth, but the present invention is not limited to this configuration. The band saw blade may be classified into more than three types of cutting widths corresponding to finer set amounts.
Although a band saw blade has been described in the first and second embodiments, the saw blade is not limited to a band saw blade and may be a circular saw blade or the like.

1 Body portion 2A, 2B Saw tooth portion 91A, 91B Band saw blade A Reference C11, C12, C21, C22 Straight tooth CG Straight tooth functional group L11, L12, L13, L21, L22, L23 Left set tooth LG Left set tooth functional group R11, R12, R13, R21, R22, R23 Right set tooth RG Right set tooth functional group G1, G1-1, G1-2, G2, Saw tooth group P11 to P14, P21 to P28 Tooth tip pitch KPC11, KPC21, KPC22 Straight tooth tip functional pitch KPL11, KPL12, KPL13, KPL21, KPL22, KPL23 Left set tooth tip functional pitch KPR11, KPR12, KPR13, KPR21, KPR22, KPR23 Right set tooth tip functional pitch LN, LN1, LN2 Root line P11 to P14, P21 to P28 Tooth tip pitch PT1 Tooth tip pitch pattern S, M, L Tooth tip area T1 to T7 Sawtooth T1a Relief face T1b Projection portion T1c Gouged portion WP Workpiece Wm Cutting groove Wa Overall width W1, W2, W3 Cutting width θa Rake angle θb Clearance angle

Claims (3)

The sawtooth section has a repeating sawtooth set in a certain order, the sawtooth set including two straight teeth having a first function of cutting with a first cutting width, three left set teeth having a second function of cutting with a second cutting width, and three right set teeth having a third function of cutting with a third cutting width, the sawtooth set being formed as sawtooth;
The fixed order is, facing the opposite direction of the running direction during cutting, a straight tooth, a right set tooth, a left set tooth, a right set tooth, a straight tooth, a left set tooth, a right set tooth, a left set tooth,
The three left set teeth are a left set tooth functional set,
The three right set teeth are a right set tooth functional set,
The tooth tip pitches of adjacent left set teeth in the left set tooth functional set of one saw tooth set are defined as a first pitch and a second pitch from the front side in the traveling direction, and the tooth tip pitch between the rearmost left set tooth and the foremost left set tooth of the saw tooth set adjacent to the rear side of the one saw tooth set is defined as a third pitch,
When the tooth tip pitches of adjacent right set teeth in the right set tooth functional group of the one saw tooth group are defined as a fourth pitch and a fifth pitch from the front side in the traveling direction, and the tooth tip pitch between the rearmost right set tooth and the right set tooth furthest in the traveling direction in the saw tooth group adjacent to the rear side of the one saw tooth group is defined as a sixth pitch,
the first pitch, the second pitch, and the third pitch are different from one another and have a first magnitude relationship;
the fourth pitch, the fifth pitch, and the sixth pitch are different from one another according to a second magnitude relationship;
When the magnitude of the tooth tip area of the sawtooth is associated with the magnitude of the tooth tip mass set by the presence or absence of a protruding portion on the flank and the difference in the protruding amount when the protruding portion is present, or the presence or absence of a hollowed-out portion on the flank and the difference in the hollowed-out amount when the hollowed-out portion is present,
In each of the first pitch, the second pitch, and the third pitch, the magnitude relationship of the tooth tip areas of the left set tooth on the opposite side to the traveling direction coincides with the first magnitude relationship,
A saw blade in which the dimensional relationship of the tooth tip areas of the right set teeth on the opposite side to the traveling direction at each of the fourth pitch, the fifth pitch, and the sixth pitch coincides with the second dimensional relationship . When a tooth tip pitch of the two straight teeth in the sawtooth set is defined as a seventh pitch, a tooth tip pitch of the straight tooth on the rear side and the straight tooth on the side furthest in the traveling direction in the sawtooth set adjacent to the rear side of one of the sawtooth sets is defined as an eighth pitch, and a magnitude relationship between the seventh pitch and the eighth pitch is defined as a third magnitude relationship,
2. The saw blade according to claim 1 , wherein the relationship in magnitude between the tooth tip areas of the straight teeth on the opposite side to the traveling direction in each of the seventh pitch and the eighth pitch coincides with the third relationship in magnitude . The saw blade according to claim 1 or claim 2, wherein the saw blade is a band saw blade.

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