WO2013083019A1

WO2013083019A1 - Saw blade

Info

Publication number: WO2013083019A1
Application number: PCT/CN2012/085739
Authority: WO
Inventors: Gang Liu
Original assignee: Bosch Power Tools (China) Co., Ltd.
Priority date: 2011-12-06
Filing date: 2012-12-03
Publication date: 2013-06-13
Also published as: CN103143774B; CN103143774A

Abstract

A saw blade (1) comprises a saw blade body (5) having a plurality of tooth seats (7) and tips (15) attached respectively to respective tooth seats (7) of the saw blade body (5). The saw blade body (5) comprises two or three saw blade body parts (3) which can fixed together, and the tips (15) are sandwich tightly by the two or three saw blade body parts (3) to be secured to the tooth seats (7). According to the saw blade (5) of the present invention, the tips (15) may be attached fixedly to the saw blade body (5) without using any welding process, the tips (15) each may be separately detached and replaced, and it is possible to reduce the vibration and the noise during operation of the saw blade (1).

Description

Saw blade

FIELD OF THE INVENTION

The present invention relates to a saw blade.

BACKGROUND OF THE INVENTION

A saw blade is used widely to cut various materials such as timber, wood-based panel, stone, metal, nonmetal and so on. The conventional carbide saw blade generally comprises a saw blade body and a plurality of tips brazed to the tooth seats at an edge of the saw blade body. The tips are usually made from carbide material and carbide -based super-hard material. The brazing process for soldering the tips to the tooth seats needs to use some solders. The solders are not only costly but also have adverse effect on the environment. The high temperature during brazing results in an increasing stress in the carbide tips, thereby increasing the probability of breaking the tips. The high temperature during brazing also deteriorates the flatness of the soldering region of the saw blade so that a subsequent flattening treatment is necessary.

With the use of the saw blade, the tips become gradually blunt. During cutting the tips are even damaged, for example partially broken or missed, thereby causing inefficient cutting or causing the saw blade out of operation. Because the tips are soldered to the tooth seats, each of the blunt or broken tips needs to be sharpened or be replaced by brazing a new tip individually. Obviously, sharpening the tip or re-brazing a new tip individually is inefficient.

To solve these problems, CN201565672U proposes a reusable saw blade. The saw blade comprises a saw blade body having a projecting shoulder and a plurality of sectors. The sectors each are provided at its inner edge with a groove for matching with the projecting shoulder of the saw blade body and at its outer edge with a plurality of tooth seats to each of which a tip is brazed. The plurality of sectors are arranged closely and riveted onto the saw blade body. When a tip becomes blunt or broken, it is still possible to use the saw blade by replacing the respective sector. However, the brazing process is still required for such a saw blade to solder the tips to the tooth seats. Further, when only some of the tips on one sector become blunt or broken, replacing the whole sector is wasteful too. Moreover, sharpening or re-brazing to replace the individual tip soldered to the sector is still inefficient Thus, there is a need to make some improvements on the conventional saw blade.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to overcomes the above-mentioned shortcomings in the prior art and provide a saw blade. According to the saw blade of the present invention, the tips may be attached fixedly to the saw blade body without using any welding process, the tips each may be separately detached and replaced, and it is possible to reduce the vibration and the noise during operation of the saw blade.

According to one aspect of the present invention, it is to provide a saw blade comprising:

a saw blade body having a plurality of tooth seats; and

tips attached respectively to a respective tooth seat of the saw blade body;

wherein the saw blade body comprises two or three saw blade body parts which can be fixed together, and the tips are sandwiched tightly by the two or three saw blade body parts to be secured to the tooth seats.

Preferably, a mounting portion is formed on one of the tooth seats on at least one saw blade body part and the tips, and a structure which matches with the mounting portion is formed in the other one of the tooth seats on at least one saw blade body part and the tips.

Preferably, the mounting portion is formed on the tips and extends from the tip body, and the structure which matches with the mounting portion is formed in the at least one saw blade body part.

Preferably, the two or three saw blade body parts comprise an identical tooth shoulder having the identical tooth seats.

Preferably, the structure which is formed in the saw blade body part and matches with the mounting portion is a cavity, the shape of the cavity matches with the shape of the mounting portion on the tips and the cavity is used to receive the mounting portion on the tips. Preferably, a plurality of aligned through holes are formed respectively in the two or three saw blade body parts, and the two or three saw blade body parts are fixed together by means of the fasteners passing through the through holes to sandwich tightly the tips.

Preferably, the depth of the cavity is chosen such that there is no gap between the adjacent saw blade body parts when the two or three saw blade body parts are fixed together.

Preferably, an insert is disposed between the adjacent saw blade body parts of the two or three saw blade body parts, and the insert is made from a further material that is different from a material of the saw blade body parts.

Preferably, one of the two or three saw blade body parts is provided with a boss, and the other of the two or three saw blade body parts is provided correspondingly with an opening for receiving the boss.

Preferably, the saw blade is a circular saw blade, and the saw blade body parts are circular.

Preferably, the saw blade is an elongate saw blade, and the saw blade body parts are elongate.

Preferably, the saw blade body comprises two circular saw blade body parts, the first saw blade body part has the same outer diameter and the same tooth seats in number and shape as the second saw blade body part, the opposite surfaces of the tooth seats of the first saw blade body part and the tooth seats of the second saw blade body part are provided respectively at a corresponding position with a cavity, the tips comprises a tip body and a mounting portion extending from the tip body, the cavity has a shape which matches with the shape of the mounting portion of the tips to receive the mounting portion of the tips.

Preferably, a central recess is formed in a central portion of the opposite surfaces of the first saw blade body part and the second saw blade body part, an insert is disposed within the central recess, and the insert is made from a further material that is different from a material of the first saw blade body part and the second saw blade body part. Preferably, the saw blade body comprises three circular saw blade body parts, and a through cavity for receiving partially the tip is formed in a central saw blade body part of the three circular saw blade body parts.

Preferably, the other two of the three circular saw blade body parts are annular, the two annular saw blade body parts sandwich the central saw blade body part and fix the tips in position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a saw blade according to the present invention;

FIG. 1A is an enlarged view showing a portion of one saw blade body part of Fig 1 and the tips corresponding to the portion;

FIG. 2 is a side view of an embodiment of a tip according to the present invention;

FIG. 2A is a right view of the tip shown in FIG2;

FIG. 3 is an enlarged view showing a portion of a saw blade body part corresponding to the tip shown in FIG 2;

FIG. 4 is a side view of a further embodiment of a tip according to the present invention;

FIG. 4A is a right view of the tip shown in FIG4;

FIG. 5 is an enlarged view showing a portion of a saw blade body part corresponding to the tip shown in FIG 4;

FIG. 6 is a partially enlarged view showing the tip shown in FIG 4 disposed within a cavity of the saw blade body part shown in FIG 5; and

FIG. 7 is a perspective view of the saw blade body parts according to a further embodiment of the present invention with a tooth shoulder comprising the tooth seats at the outer edge of the saw blade body parts to be omitted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments will be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view of a saw blade according to the present invention. FIG. 1A is an enlarged view showing a portion of one saw blade body part of Fig 1 and the tips corresponding to the part. As shown in FIGS 1 and 1A, the saw blade 1 according to the present invention comprises a first saw blade body part 3 in a circular shape and a second saw blade body 5 in a circular shape. A tooth shoulder 6 at an outer edge of the first saw blade body part 3 is provided with a plurality of tooth seats 7. A tooth shoulder 8 at an outer edge of the second saw blade body part 5 is provided with a plurality of tooth seats 9. The first saw blade body part 3 has the same outer diameter and the same tooth seats in number and shape as the second saw blade body part 5. The opposite surface of each of the tooth seats 7 and 9 is provided respectively at a corresponding position with a cavity 13 opening to a side of the tooth seats to which the tips are attached (in the drawings, the cavity 13 in the tooth seats 9 of the second saw blade body part 5 is invisible). The saw blade 1 according to the present invention further comprises a plurality of tips 15 which each comprises a tip body 17 and a mounting portion 21 extending from the tip body 17 and opposite to a cutting edge 19 of the tip body 17.

The cavity 13 in each of the tooth seats 7 and 9 has a shape matching with that of the mounting portion 21 of the tip 15. For example, when the mounting portion 21 of the tip 15 is inclined to the tip body 17 as shown in FIGS 2 and 2A, the cavity 13 in each of the tooth seats 7 and 9 is also obliquely arranged as shown in FIG 3; when the mounting portion 21 of the tip 15 is substantially T-shaped as shown in FIGS 4 and 4A, the cavity 13 in each of the tooth seats 7 and 9 is also substantially T-shaped as shown in FIG 5. It is envisaged for a person skilled in the art that it is possible to devise the mounting portion 21 and the cavity 13 in other various shapes such as L-shape or star-shape. The shape match between the cavity 13 in each of the tooth seats 7 and 9 and the mounting portion 21 of the tip 15 may ensure that the tip 15 is sandwiched fixedly between the first saw blade body part 3 and the second saw blade body part 5. Please note that the term "cavity" used herein should be broadly understood to be any structure that can receive the mounting portion of the tip. Of course, it is also feasible that a projecting mounting portion is formed on each of the tooth seats and a cavity whose shape matches with the shape of the mounting portion on the tooth seats is formed in each of the tips.

A through hole 23 is formed in each of the tooth seats 7 of the first saw blade body part 3. A through hole 25 is formed correspondingly in each of the tooth seats 9 of the second saw blade body part 5. A fastener such as a blot or a rivet may pass through the through holes 23 and 25 to fix tightly the first saw blade body part 3 and the second saw blade body part 5 together. It is also possible that the first saw blade body part 3 and the second saw blade body part 5 are fixed tightly together by means of other ways such as soldering and gluing. The first saw blade body part 3 and the second saw blade body part 5 are also provided with a central hole 27 and 29 respectively to attach the assembled saw blade body to a driving shaft (not shown).

How to assemble the saw blade 1 according to the present invention is described below.

Firstly, one saw blade body part for example the first saw blade body part 3 is laid horizontally. Then, the tip 15 is placed within the cavity 13 of each of the tooth seats 7 of the first saw blade body part 3 so that the tip body 17 of the tip 15 abuts against the tooth seat 7 and the mounting portion 21 of the tip 15 is positioned in the cavity 13 of the tooth seat 7 while they match in shape with each other, as shown in FIG 6. Then, the second saw blade body part 5 is overlaid onto the first saw blade body part 3 so that each of the tooth seats 9 of the second saw blade body part 5 aligns with each of the tooth seats 7 of the first saw blade body part 3 to ensure that the mounting portion 21 of the tip 15 is also positioned partially in the cavity 13 of each of the tooth seats 9 of the second saw blade body part 5. Finally, by means of the fasteners passing through the through holes 23 in each of the tooth seats 7 and the corresponding through holes 25 in each of the tooth seats 9, the first saw blade body part 3 and the second saw blade body part 5 are fixed tightly together to form a complete saw blade 1.

In the above-mentioned embodiment, both the tooth seats 7 of the first saw blade body part 3 and the tooth seats 9 of the second saw blade body part 5 are provided with the cavity 13. It should be understood that, only one of the first saw blade body part 3 and the second saw blade body part 5 is provided with the cavity 13. However, this situation may cause an increasing vibration and noise during operation of the saw blade. It is also feasible that every other one of all the tooth seats 7 of the first saw blade body part 3 and all the tooth seats 9 of the second saw blade body part 5 is provided with the cavity 13. In this situation, when the first saw blade body part 3 and the second saw blade body part 5 are fixed tightly together, the tooth seats 7 of the first saw blade body part 3 provided with the cavity 13 align or stagger with the tooth seats 9 of the second saw blade body part 5 provided with the cavity 13. In any situation, the depth of the cavity 13 is chosen so that there is almost no gap between the first saw blade body part 3 and the second saw blade body part 5 and the tips 15 are sandwiched fixedly between the first saw blade body part 3 and the second saw blade body part 5 when the first saw blade body part 3 and the second saw blade body part 5 are fixed tightly together. A central recess 31 (in Fig 1, the central recess 31 of the second saw blade body part 5 is invisible) may be formed in a central portion of the opposite surfaces of the first saw blade body part 3 and the second saw blade body part 5 respectively. When the first saw blade body part 3 and the second saw blade body part 5 are fixed tightly together, an insert 33 with a central hole 35 may be disposed within the central recess 31 so that the central hole 35 of the insert 33 aligns with the central hole 27 of the first saw blade body part 3 and the central hole 29 of the second saw blade body part 5 and the insert 33 is sandwiched fixedly between the first saw blade body part 3 and the second saw blade body part 5. The insert 33 is made from a further material that is different from the material of the first saw blade body part 3 and the second saw blade body part 5. Preferably, the through holes 3a, 5a and 33a which align with each other are formed in the central portion of the first saw blade body part 3 and the second saw blade body part 5 and in the insert 33 respectively to further fix the first saw blade body part 3, the insert 33 and the second saw blade body part 5. Since the material from which the insert 33 is made is different from the material of the first saw blade body part 3 and the second saw blade body part 5, it is possible to reduce the vibration frequency and the noise during operation of the saw blade.

FIG. 7 is a perspective view of the saw blade body parts according to a further embodiment of the present invention with a tooth shoulder comprising the tooth seats at the outer edge of the saw blade body parts to be omitted. As shown in FIG 7, the first saw blade body part 3' comprises a boss 37 around the central hole 27', and the second saw blade body part 5' comprises an opening 39 whose shape corresponds with the shape of the boss 37 of the first saw blade body part 3' . Both the boss 37 and the opening 39 are shown to be circular in FIG 7. However, it should be understood that the boss 37 and the opening 39 may be in any other suitable shape such as ellipse, square or triangle. When the first saw blade body part 3' and the second saw blade body part 5' are fixed tightly together, the boss 37 is received within the opening 39. It should be understood that the number of the boss 37 and the opening 39 may be more than one and they may be arranged at any other position other than the center. Further, it is also possible for both saw blade body parts to be provided with the boss and the corresponding opening.

In the above-mentioned preferred embodiments, the saw blade according to the present invention is shown to be circular. However, it should be understood that the present invention also applies to an elongate saw blade. For the elongate saw blade, the first saw blade body part and the second saw blade body part are elongate too.

Further, according to a variant of the present invention, the saw blade of the present invention may comprise thee saw blade body parts. A through cavity for receiving the mounting portion of the tip is formed in the tooth seats of the central one of the three saw blade body parts. The tooth seats of the other two saw blade body parts may be provided with or without a corresponding cavity. The central saw blade body part and the tips are sandwiched fixedly between the other two saw blade body parts. For a circular saw blade, the other two saw blade body parts are preferably in a substantially annular shape. For an elongate circular saw blade, the width of the other two saw blade body parts is preferably less than that of the central saw blade body. Thus, the central saw blade body part may be sandwiched by the other two saw blade body parts only at the tooth shoulder portion of the central saw blade body part including the tooth seats. In this way, it is possible to save the material used to form the saw blade body parts.

As stated, the saw blade according to the present invention sandwiches tightly the tips by means of two or three saw blade body parts to fix the tips in place without using a brazing process. According to the present invention, it is unnecessary to use the expensive solder, which not only reduces the cost of the saw blade but also does not have adverse effect on the environment. Further, the present invention also avoids the risk of breaking the tips caused by the high temperature during brazing and a subsequent flattening treatment.

In the situation that the saw blade body parts are fixed together by means of the fasteners such as bolts or riveters, when a tip becomes blunt or broken, it is possible to replace only the blunt or broken tip, thereby reducing the expensive in use. The blunt or broken and replaced tips may be collected and treated in batches, thereby enhancing substantially the efficiency of the treatment. Since the tips are attached removably to the saw blade body, they may be replaced with a different type of tips to meet the different cuttings. Further, the cutting speed of the saw blade may be changed by increasing or decreasing the number of the tips.

Additionally, the saw blade body of the saw blade according to the present invention has a multilayer structure comprising two or three saw blade body parts, which may reduce the vibration and thus the noise during operation of the saw blade.

Although the invention has been described in detail in connection with the preferred embodiments, it is to be understood that such detail is solely for the purpose of illustrating the present invention and does not form a limit to the present invention. The present invention is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims.

Claims

1. A saw blade comprising:

a saw blade body having a plurality of tooth seats; and

tips attached respectively to a respective tooth seat of the saw blade body;

2. The saw blade according to claim 1, wherein a mounting portion is formed on one of the tooth seats on at least one saw blade body part and the tips, and a structure which matches with the mounting portion is formed in the other one of the tooth seats on at least one saw blade body part and the tips.

3. The saw blade according to claim 2, wherein the mounting portion is formed on the tips and extends from the tip body, and the structure which matches with the mounting portion is formed in the at least one saw blade body part.

4. The saw blade according to claim 1, wherein the two or three saw blade body parts comprise an identical tooth shoulder having the identical tooth seats.

5. The saw blade according to claim 3, wherein the structure which is formed in the saw blade body part and matches with the mounting portion is a cavity, the shape of the cavity matches with the shape of the mounting portion on the tips and the cavity is used to receive the mounting portion on the tips.

6. The saw blade according to claim 1, wherein a plurality of aligned through holes are formed respectively in the two or three saw blade body parts, and the two or three saw blade body parts are fixed together by means of the fasteners passing through the through holes to sandwich tightly the tips.

7. The saw blade according to claim 5, wherein the depth of the cavity is chosen such that there is no gap between the adjacent saw blade body parts when the two or three saw blade body parts are fixed together.

8. The saw blade according to claim 1, wherein an insert is disposed between the adjacent saw blade body parts of the two or three saw blade body parts, and the insert is made from a further material that is different from a material of the saw blade body parts.

9. The saw blade according to claim 1, wherein one of the two or three saw blade body parts is provided with a boss, and the other of the two or three saw blade body parts is provided correspondingly with an opening for receiving the boss.

10. The saw blade according to claim 1, wherein the saw blade is a circular saw blade, and the saw blade body parts are circular.

11. The saw blade according to claim 1, wherein the saw blade is an elongate saw blade, and the saw blade body parts are elongate.

12. The saw blade according to claim 1, wherein the saw blade body comprises two circular saw blade body parts, the first saw blade body part has the same outer diameter and the same tooth seats in number and shape as the second saw blade body part, the opposite surfaces of the tooth seats of the first saw blade body part and the tooth seats of the second saw blade body part are provided respectively at a corresponding position with a cavity, the tips comprises a tip body and a mounting portion extending from the tip body, the cavity has a shape which matches with the shape of the mounting portion of the tips to receive the mounting portion of the tips.

13. The saw blade according to claim 12, wherein a central recess is formed in a central portion of the opposite surfaces of the first saw blade body part and the second saw blade body part, an insert is disposed within the central recess, and the insert is made from a further material that is different from a material of the first saw blade body part and the second saw blade body part.

14. The saw blade according to claim 3, wherein the saw blade body comprises three circular saw blade body parts, and a through cavity for receiving partially the tip is formed in a central saw blade body part of the three circular saw blade body parts.

15. The saw blade according to claim 14, wherein the other two of the three circular saw blade body parts are annular, the two annular saw blade body parts sandwich the central saw blade body part and fix the tips in position.