JP7260547B2 - circular saw - Google Patents

Description

The present invention relates to a circular saw in which a plurality of cutting tips are joined to the outer periphery of a base metal, which can reduce the sound pressure level of noise generated during cutting and facilitates polishing of the cutting tips by an automatic polishing machine. Circular saw.

Circular saws, which have a large number of cutting tips bonded to the outer circumference of a circular base metal, are used for rotary cutting (hereinafter referred to as "cutting") of various materials such as wood, metal, and synthetic resin (hereinafter referred to as "work material"). .

Japanese Patent No. 3030705 Utility Model Registration No. 3176639

When cutting various work materials with a circular saw, depending on the material, hardness, or shape of the work material, the noise generated during cutting is loud and the sound range is high, making the work environment unpleasant. making it worse

For example, at the cutting site of work materials made of aluminum alloy, there is a demand for improvement of the poor work environment due to loud cutting noise in the high frequency range. In addition, since the former Ministry of Labor formulated the "Guidelines for Preventing Noise Disturbances" (October 1992), each business establishment has been working on noise countermeasures. In the field of circular saw machines using circular saws as well, according to the above-mentioned guidelines, there is a demand for reducing the noise generated in the cutting work using circular saw machines. Noise is generally evaluated by sound pressure level (a unit of noise level measured by a sound level meter having an A-characteristic dBA auditory sense correction circuit).

In a general circular saw, the intervals (pitch) between adjacent cutting tips are even with respect to the many cutting tips joined to the outer circumference of the base metal, and the work material and each cutting tip are separated during cutting. contact period is constant. For this reason, a loud sound of a specific frequency is generated during cutting of the work material, which is a source of noise. Pitch here refers to the interval between adjacent saw teeth in one chip group (A, B, C, ...) (Dictionary of Wood Processing Terms, The Japan Wood Society, Machining Study Group). say.

In this way, if the pitch of the cutting tip is the same, a high-pitched sound of a specific frequency is generated during cutting, causing noise. An irregular circular saw has been proposed. For example, for cutting tips that are joined to the outer periphery of a circular base metal, if five tips are arranged so that one set of teeth is sequentially connected, one set (5 tips) has four cutting tips with equal pitches. , and the remaining one cutting tip is a circular saw with a different pitch from the other cutting tip. This can be evaluated in that it is effective in reducing noise during cutting because the sound generated during cutting does not have a specific frequency and the peak frequency is dispersed.

However, since the sharpness of the cutting tip of the circular saw gradually deteriorates with use, it is necessary to polish the tip periodically or irregularly. Further, when a circular saw (new product) with a cutting tip bonded to the outer periphery is manufactured, grinding for sharpening is required. An automatic grinder is generally used for sharpening a new cutting tip or resharpening the cutting tip of the circular saw. That is, a circular saw attached to an index shaft of an automatic grinder is rotated one pitch at a time by the number of cutting chips, and the chips are sharpened and ground with a grindstone rotating at a fixed position. This operation poses no problem for an automatic grinder if the pitch of each cutting tip in the circular saw is constant. However, if the pitch of the cutting tip described above is irregular, it is necessary to numerically control the irregular pitch with the control device of the automatic polishing machine, and in some cases the range of numerical control may be exceeded. There is a problem that it cannot be dealt with by an automatic polishing machine.

In order to solve the above problems and achieve the intended purpose, the invention according to claim 1,
In a circular saw in which a required number of cutting tips are joined to the outer periphery of a base metal,
Two or more tip groups are provided in which a large number of cutting tips are arranged on the outer circumference of the circular saw,
The pitches of the chips in each chip group are set so that the pitch between the last chip and the first chip is an arbitrary value, and the others are set equal.
The equal pitch of at least one chip group among the two or more chip groups and the equal pitch of the other chip groups are different in pitch dimension,
The gist is that three or more chips in the same chip group are not arranged continuously in the outer peripheral direction.
According to the first aspect of the invention, since the pitches of a large number of cutting tips are changed for each tip group, the pitches of each tip group can be memorized in the automatic polishing machine. Automatic polishing can be achieved without large numerical changes. In addition, by not arranging three or more chips of the same chip group continuously in the outer peripheral direction, the chips of each chip group are dispersed over the entire circular saw, so that there is no bias in the pitch of adjacent chips.

In the second aspect of the present invention, the gist is that all the pitches in at least one chip group among the two or more chip groups are equal.

The gist of the third aspect of the invention is that two chip groups are provided.

According to the present invention, even if the pitch of the cutting chips joined to the outer periphery of the circular saw is irregular, the combination of the cutting chips enables grinding of the cutting chips with a constant pitch. It can be polished in an automatic polishing machine without major modifications.

FIG. 2 shows the arrangement of two groups of cutting chips in a circular saw according to an embodiment of the present invention, FIG. Partial front view of an array of cutting tips joined in the circumferential direction, (c) shows the shape of the rake face of each tip in (1), (2), and (3) described in (a) and (b) The upper side is a tip cutting edge. FIG. 2 is a schematic front view of a circular saw showing Modification 1 of the embodiment shown in FIG. 1; FIG. 3 is a table showing pitches of tip groups A and B of the circular saw shown in Modification 1 of FIG. 2 and pitches of adjacent tips; FIG. 2 is a schematic front view of a circular saw showing Modification 2 of the embodiment shown in FIG. 1. FIG. FIG. 5 is a table showing the pitches of tip group A and tip group B of the circular saw shown in modified example 2 of FIG. 4 and the pitches of adjacent tips; FIG. FIG. 11 is a schematic front view of a circular saw showing a modified example 3 of the embodiment shown in FIG. 1; FIG. 7 is a table showing pitches of chip groups A, chip groups B, and chip groups C of the circular saw shown in modified example 3 of FIG. 6 and pitches of adjacent chips; FIG.

In the circular saw according to the present invention, in order to reduce noise when cutting a work material, the basic structure of intentionally changing the pitch of a large number of cutting tips joined to the outer circumference of the circular saw base is as described above. Common with prior art circular saws. However, in the present invention, a certain regularity is given to the pitch of the cutting tip so that the cutting tip can be ground within the numerical control range of the automatic grinding machine.

FIG. 1 shows the arrangement of cutting tips in a circular saw according to a preferred embodiment of the present invention. FIG. FIG. 1(a) is a partial plan view of the arrangement of cutting tips 14 in FIG. 1(b) observed from above. In this embodiment, the number of cutting chips in the chip group A is 75, and the number of cutting chips in the chip group B is 75. That is, as shown in FIGS. 1(a) and 1(b), on the outer periphery of the base metal 12, a plurality of cutting tips 14 are arranged on the outer periphery of the circular saw 10, and the tips A ₁ to A ₇₅ of the tip group A are arranged. Chips B ₁ to B ₇₅ of chip group B are alternately arranged. The number of cutting tips 14 in each tip group A (B) may be arbitrary. Also, in this embodiment, there are two chip groups A and B, but the number of chip groups may be increased.

In this specification, chip A ₀ is used to indicate any chip in the chip group A, and specific individual chips are indicated by chip A ₁ , chip A ₂ . . . chip A _{m- 1.} , chip A _m . Similarly, chip B ₀ shall be used when indicating any chip in the chip group B, and when indicating individual specific chips, chip B ₁ , chip _{B 2 .} . . _Bn .

In the embodiment of FIG. 1, the pitch of the chips _A0 constituting the chip group A is equal to the pitch .chi. as shown in FIGS. 1(a) and 1(b). However, regarding the chip group A, the pitch between the last chip A ₇₅ and the first chip A ₁ in the circumferential direction of the base metal is set to a pitch χ′ different from the equal pitch χ. All the chips _B0 in the chip group B have an equal pitch y as shown in FIGS. 1(a) and 1(b). In the circular saw according to the embodiment of the present invention, _the chips A 0 , B ₀ , . . . of the same chip groups A, B, . 1 or more are not continuously arranged in the outer peripheral direction. Here, when the pitch is represented by central angles, χ=4.8196°, χ′=3.3496°, and y=4.8°.

For each chip _A0 and _B0 in the chip group A and chip group B, as shown in FIG. (1), (2), (3), . . . That is, in FIG. 1(c), the tip cutting edge of the tip indicated by (1) is inclined on the right side, and the tip cutting edge of the tip indicated by (2) is inclined on the left side. Also, both sides of the cutting edge at the tip of the tip shown by (3) are inclined. By sequentially changing the shape of the rake face of each insert in this manner, noise during cutting can be suppressed to a low level. For example, when a circular saw with an outer diameter of 455 mm is used to cut an aluminum sash at a rotation speed of 3600 rpm, the cutting noise is 98 dBA, which is lower than 103 dBA in the case of a conventional circular saw with all teeth having the same pitch. ing. Note that the tip (1) and the tip (2) may be provided with a lateral rake angle, in which case the noise can be further suppressed.

(Modification 1)
Modification 1 of the embodiment described with reference to FIG. 1 will be described with reference to FIGS. 2 and 3. FIG. That is, Modification 1 relates to another pitch of the cutting tips 14. The circular saw ₁₀ shown in FIG. of chips _B0 are arranged alternately. Here, the pitch of each chip shown in FIG. 2 is represented by the central angle.

The central angles of the chip groups A and B have the relationship shown in the table of FIG. For example, in chip group A, the pitch between chip A ₁ and chip A ₂ is 60 degrees, which is the sum _of the pitch α ₁ (25°) of the adjacent chips and the pitch α ₂ (35°) of the adjacent chips. The pitch of _A3 is 60°, which is the sum of the pitch _α3 (27°) of the adjacent chip and the pitch _α4 (33°) of the adjacent chip, and in the same way, the last chip _A6 and the first chip _A1. is 60° which is the sum of the pitch _α11 of the adjacent chip and the pitch _α12 of the adjacent chip. Therefore, in the embodiment shown in FIG. 2, all the pitches in the chip group A are equal.

In chip group B, the pitch between chip _{B1 and} chip _B2 is 62 degrees, which is the sum of the pitch _β2 (35°) of the adjacent chip and the pitch _β3 (27°) of the adjacent chip. ₃ is 62° which is the sum of _the pitch β ₄ (33°) of the adjacent chip and the pitch β ₅ ( ₂₉ °) of the adjacent chip. It is 62° which is the sum of the chip pitch β ₁₀ (27°) and the adjacent chip pitch β ₁₁ (35°). However, the pitch between the last chip _B6 and the first chip _B1 is 50° which is the sum of the pitch _β12 (25°) of the adjacent chip and the pitch _β1 (25°) of the adjacent chip. The pitch of each chip in the chip group B is 62°. Adjacent tips of the circular saw are 6 kinds ranging from 25° to 35°, arranged irregularly and with uneven pitch.

(Modification 2)
Next, in Modified Example 2 shown in FIGS. 4 and 5, in one chip group A, the pitch between chip _A0 and the next chip _A0 is not equal, and in the other chip group B, It shows a form in which there is an unequal pitch between a chip _B0 and the next chip _B0 . In the circular saw 10 shown in FIG. 4, the tips _A0 of the tip group A and the tips _B0 of the tip group B are alternately arranged. Here, the pitch of each chip shown in FIG. 4 is represented by the central angle.

The central angles of the chip groups A and B have the relationship shown in the table of FIG. For example, in chip group A, the pitch between chips A ₁ and A ₂ is 58 degrees, which is the sum of the pitch α ₁ (25°) of the adjacent _chips and the pitch α ₂ (33°) of the adjacent chips. ₃ is 58°, which is the sum of the pitch α ₃ (29°) of the adjacent chip and the pitch α ₄ (29°) of the adjacent chip, and in the same way the pitch between chip A ₅ and chip A ₆ is the adjacent chip pitch 58° which is the sum of the pitch α ₉ (41°) of the chip and the pitch α ₁₀ (17°) of the adjacent chip. However, the pitch between the chips A ₆ and A ₁ is 70 degrees, which is the sum of the pitch α ₁₁ (45°) of the adjacent chips and the pitch α ₁₂ (25°) of the adjacent chips.

In chip group B, the pitch between chip _B1 and chip _B2 is 62°, which is the sum of the pitch _β2 (33°) of _the adjacent chip and the pitch _β3 (29°) of the adjacent chip. The pitch of _B3 is 62 _° which is the sum of the pitch _β4 (29°) of the adjacent chip and the pitch _β5 ( ₃₃ °) of the adjacent chip. It is 62° _{which is the sum of the pitch β 10 (} 17°) of the adjacent chips and the pitch β ₁₁ (45°) of the adjacent chips. However, the pitch between the last chip _B6 and the first chip _B1 is 50° which is the sum of the pitch _β12 (25°) of the adjacent chips and the pitch _β1 (25°) of the adjacent chips. It differs from the previous pitch of 62°. Also, the pitches of the adjacent tips of the circular saw are unequal pitches arranged irregularly in eight types ranging from 17° to 45°.

(Modification 3)
Next, in Modified Example 3 shown in FIGS. 6 and 7, the pitches of chips _A0 in chip group A are all equal, but there are chips that are not equal to the pitch of chips _B0 in chip group B, and chip group C also shows a form in which there is a pitch that is not equal to the pitch of the chip _C0 . In the circular saw 10 shown in FIG. 6, the chips _A0 of the chip group A, the chips _B0 of the chip group B, and the chips _C0 of the chip group C are arranged alternately. there is Here, the pitch of each chip shown in FIG. 6 is represented by the central angle.

The central angles of the chip groups A, B, and C have the relationship shown in the table of FIG. Here, the pitches of the chips _A0 in the chip group A are all equal. However, in chip group B, for example, the pitches of chip _B1 and chip _B2 are the pitch _β2 (33°) of adjacent chips, the pitch _β3 (25°) of adjacent chips, and the pitch _β4 (25°) of adjacent chips. 30.5°) is 88.5°. The pitches of the chips _B2 and _B3 are the pitch _β5 (31.5°) of the adjacent chips, the pitch _β6 (28°) of the adjacent chips, and the pitch _β7 (29°) of the adjacent chips. The sum is 88.5°. Similarly, the pitches of the chips _B3 and _B4 are the pitch _β8 (30°) of the adjacent chips, the pitch _β9 (31°) of the adjacent chips, and the pitch _β10 (27.5°) of the adjacent chips. °) is 88.5°. However, the pitches of the chips _B4 and _B1 are the pitch _β11 (28.5°) of the adjacent chips, the pitch _β12 (34°) of the adjacent chips, and the pitch _β1 (32°) of the adjacent chips. The sum is 94.5°.

In the chip group C, the pitches of the chips _C1 and _C2 are the adjacent chip pitch γ ₃ (25°), the adjacent chip pitch γ ₄ (30.5°), and the adjacent chip pitch γ ₅ ( 31.5°) is the sum of 87°. The pitch between the chips _C2 and _C3 is the sum of the adjacent chip pitch _γ6 (28°), the adjacent chip pitch _γ7 (29°), and the adjacent chip pitch _γ8 (30°). 87°. Similarly, the pitches of chips _C3 and _C4 are the pitch of adjacent chips _γ9 (31°), the pitch of adjacent chips _γ10 (27.5°), and the pitch of adjacent chips _γ11 (28°). .5°), which is 87°. However, the pitch between the chips _C4 and _C1 is the sum of the adjacent chip pitch _γ12 (34°), the adjacent chip pitch _γ1 (32°), and the adjacent chip pitch _γ2 (33°). It is 99°. The pitches of the adjacent tips of the circular saw are 12 different pitches ranging from 25° to 34°.

As described above, according to the circular saw according to the present invention, the pitches of a large number of cutting chips are changed according to each chip group. Therefore, by simply storing the pitch of each tip group in the control device of the automatic polishing machine, automatic polishing of each cutting tip can be achieved without a large change in numerical values. For example, in modification 1, chip group A can be ground at a pitch of 60°, and then chip group B can be ground at a pitch of 62° after chip _B1 is ground. Similarly, in Modification 2, the chip _A1 of the chip group A can be ground at a pitch of 58°, and the chip _B1 of the chip group B can be ground at a pitch of 62°.

10 circular saw, 12 base metal, 14 tip for cutting, A ₀ , B ₀ tip,
A, B chip group, A ₁ , B ₁ first chip, A _m , B _n last chip

Claims (3)

A circular saw in which a required number of cutting tips (14) are joined to the outer circumference of a base metal (12),
Two or more tip groups (A, B, .
The pitches of the chips (A ₀ , B ₀ , . _. . ) in each chip group ₍ A _, B _, . ) is an arbitrary value, the others are set equal,
The equal pitch of at least one chip group (A, B, . . . ) in the two or more chip groups (A, B, . . . ) and the equal pitch of the other chip groups (A, B, . are different and
A circular saw characterized in that three or more tips (A ₀ , B ₀ , . . . ) of the same tip group (A, B, . 2. The circular saw according to claim 1, wherein at least one tip group (A, B, . . . ) among said two or more tip groups (A, B, . . . ) has the same pitch. 3. A circular saw according to claim 1, wherein said two groups of chips (A, B) are provided.

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