JPH067862Y2 - Cutting blade with cutting edge tip - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is a cutting blade (circular saw, which has a blade tip fixed to a base metal,
(Including hole saw).

<Prior art> Today, various cutting blades have
The one to which a cutting edge tip such as cemented carbide, CBN or ceramic is attached is widely used. And various mounting structures have been proposed, for example, in Japanese Utility Model Laid-Open No. 61-112825.
Like the blade tip of the saw described in Japanese Patent Publication, in order to secure the fixing of the blade tip, insert the blade tip into the receiving recess of the edge of the saw base metal and join it to the front and rear surfaces of the blade tip. It is also proposed to form a chip positioning groove that fits in front of and behind the recess.

<Problems to be Solved by the Invention> However, when the front and rear surfaces and the bottom surface of the chip are fitted and fixed to the receiving recesses of the base metal of the cutting blade in this manner, there are the following difficult problems.

Usually, brazing is used as the fixing means of the chip. And in the case of this brazing, it is common to pour silver brazing from the end of the rear surface of the chip. However, when the front and rear surfaces of the chip are fitted in the base metal concave portion, the silver braze does not sufficiently flow into each fitting portion, and therefore it is necessary to pour from the front end portion. In addition, even if it is poured from both sides in this way, the silver brazing may not be completely poured to the bottom surface of the chip, which often results in incomplete fixation.

In particular, if the tip is not fitted to the receiving recess to a predetermined depth and there is a gap between the bottom surface of the chip and the bottom wall of the receiving recess, the capillary phenomenon does not occur at this part and the flow of silver brazing stops. I will end up. Therefore, although the silver braze is also made to flow from the bottom surface of the chip, if this gap is large, it is not possible to fill the gap even by pouring the silver braze. As a result, the bottom surface of the tip is not firmly fixed to the base metal, which causes the cutting edge having the tip to come off.

Such incomplete fitting of the chip occurs even in a normal chip, but when a groove is formed in the chip, the shape of the receiving concave portion and the shape of the chip are likely to be inconsistent, and it becomes more remarkable.

<Means for Solving the Problems> Therefore, the present invention provides a cutting blade having a cutting edge formed by fixing a base of a cutting edge tip in a receiving recess formed in a base metal, and a cutting blade having a cutting edge tip characterized by the following configuration. The above-mentioned problems are solved by providing them. In the present invention, a central portion into which the base of the cutting edge tip is fitted into the receiving recess, and left and right side portions formed on both sides of the central portion and protruding in the thickness direction of the base metal,
From the left and right guide parts that project at least rearward from the left and right side parts and contact the side surfaces of the base metal, and from the bottom guide part that protrudes downward from only one of the left and right side parts and contacts the base metal side surface below the receiving recess. Become. The bottom guide portion is projected downward from the bottom surface of the central portion, so that the gap between the bottom surface of the central portion and the bottom wall of the receiving recess is covered by the bottom guide portion, and the blade tip is mounted on the table. It is glued to gold.

Here, the term “adhesion” includes not only adhesion by an adhesive but also adhesion by brazing.

<Operation> In the present invention, the bottom guide portion extends from only one of the left and right sides, and the bottom guide portion projects downward from the bottom surface of the central portion. As a result, even when the cutting edge tip is not fitted to a predetermined depth, that is, even when the bottom surface of the central portion of the cutting edge tip does not contact the bottom wall of the receiving concave portion and a gap is formed, the bottom surface of the central portion and the bottom of the receiving concave portion are formed. The gap between the wall
It is in a state of being covered by the bottom guide surface of the bottom guide portion.
This can prevent and improve the flow of silver braze or adhesive, and if the silver braze or adhesive is poured into the gap from the side of the bottom guide that is not extended, the other side of the gap will be the bottom guide surface. Since it is covered by, the gap can be filled without flowing out, and the bottom surface of the central portion of the cutting edge tip and the bottom wall of the receiving recess can be reliably joined.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

The circular saw base metal (1) of the embodiment is formed with a receiving recess (2) divided by a front wall (21), a rear wall (22) and a bottom wall (23). ), The cutting edge tip (3) is fitted and fixed.
This cutting edge tip (3) has a central part (31) and left and right side parts (32).
(33), left and right guide parts (34) and (35), and a bottom guide part (36) (each part is shown in FIG. 3 to FIG. 8 by dividing each part by a dotted line).

The central part (31) corresponds to the receiving recess (2) and the central front face (31
a), a central rear surface (31b) and a central bottom surface (31c).

The left and right side parts (32) (33) are formed on both sides of the center and
It projects in the thickness direction of (1).

The left guide part (34) projects rearward from the left side part (32), and an inner side surface thereof forms a left guide surface (34a) that abuts a side surface of the base metal.

The right guide part (35) projects rearward from the right side part (33), and an inner side surface thereof forms a right guide surface (35a) that abuts a side surface of the base metal.

The bottom guide portion (36) projects downward only from the left side portion (32), and the inner side surface thereof forms a bottom guide surface (36a) that abuts the side surface of the base metal below the receiving recess.

The left guide portion (34) and the bottom guide portion (36) are continuously formed via the left bottom guide portion (37). Further, the protruding width of the left guide portion (34) (that is, the width in the front-rear direction) is larger than the protruding width of the right guide portion (35).

The tip of the blade tip (3) may have an appropriate shape, but in the embodiment, the shape of the base is extended as it is, and the tip surface (38) is cut obliquely to form a clearance angle.

The cutting edge tip (3) is fitted into the receiving recess (2) of the base metal (FIG. 1, FIG. 9, FIG. 10). In this fitted state, the central part (31) has a front surface (31a), a rear surface (31b) and a bottom surface (31c).
Contact the front wall (21), the rear wall (22) and the bottom wall (23) of the receiving recess (2), respectively. Then, the left and right guide surfaces (34a) (35a) of the left and right guide portions abut on both side surfaces of the base metal (1) behind the receiving recess (2). Further, the bottom guide surface (36a) of the bottom guide portion contacts the left side surface of the base metal (1) below the receiving recess (2).

Thus, the cutting edge tip (3) is attached to the left and right guide surfaces (34a) (35
By the a) and the bottom guide surface (36a), the guide is fitted in the receiving recess (2) of the base metal in a state in which there is no lateral displacement.

Then, as in the conventional case, a silver braze or an adhesive is poured from the rear surface (31b) or the front surface (31a) of the cutting edge tip, and fixed by brazing or bonding.

Here, when the cutting edge tip is inserted to a predetermined depth like the tip on the left side of FIG. 1, no problem occurs, but when it is not inserted to the predetermined depth like the right tip, that is, the cutting edge tip (3 If the bottom surface (31c) of the central part of () does not abut the bottom wall (23) of the receiving recess (2) and a gap (39) occurs, conventionally,
As described above, the silver braze and the adhesive do not flow sufficiently on the bottom surface (31c), and the gap between the bottom surface (31c) and the bottom wall (23) of the receiving recess is
Even if the silver braze or adhesive is poured from (39), the silver braze or adhesive will flow out to the opposite side, and both (31c) and
The fixation of (23) was incomplete.

However, in the present invention, the bottom guide portion (36) extends from only one of the left and right side portions, that is, the left side portion in the embodiment, and the bottom guide portion (36) is the bottom surface of the central portion (31). It projects below (31c). As a result, the gap (39) between the bottom surface (31c) of the central portion and the bottom wall (23) of the receiving recess is the bottom guide portion (36).
It is in a state of being covered by the bottom guide surface (36a). As a result, it is possible to prevent the flow of silver braze or adhesive from becoming worse and improve the gap by pouring silver braze or adhesive into the gap (39) from the right side where the bottom guide part (36) is not extended. Since the left side of the is covered by the bottom guide surface (36a), without flowing out, it is possible to fill the gap (39), the central bottom surface (31c) of the cutting edge tip and the bottom wall (23) of the receiving recess. Can be reliably joined.

In the embodiment, the bottom guide portion (3
Because 6) is extended, the following advantages are created. At the time of brazing, as shown in FIGS. 9 and 10, a horn (H) is arranged on the right side to perform high-frequency heating while pouring silver silver. Then, due to the influence of the high frequency, a force for pulling the cutting edge tip to the right side is generated. Therefore, if you place the bottom guide part (36) on the left side, the bottom guide surface of the bottom guide part
The (36a) surely contacts the left side surface of the base metal, and the lid of the gap (39) also becomes reliable.

Further, as described above, the left guide portion (34) is made to protrude more than the right guide portion (35) and the surface contact of the left guide surface (34a) is made large for the same reason. That is, due to the influence of high frequency,
The left guide surface (34a) contacts the left side surface of the base metal while being pulled rightward. Therefore, by making the left guide surface (34a), which is the contacting surface, large, the position when attracted is stable, and the silver brazing is performed without wobbling.

Further, by enlarging the left guide portion (34), the following advantages occur. When this circular saw is attached to a cutting machine and the plate material is obliquely cut by the front rotation, a right-handed person inclines to the right to cut the plate material overwhelmingly. As described above, when the circular saw is obliquely positioned with respect to the plate material and is rotated toward the front, the left side of the cutting edge first contacts the plate material, and deterioration occurs from the left side. Therefore, by enlarging the left guide portion (34), the reinforcement against this deterioration becomes large, and the left and right life of the cutting edge tip becomes uniform.

Next, FIG. 10 shows an actual exploitation 63
This is an example in which a small hole (5) penetrating the left and right side portions of the base metal is formed at the corner of the bottom wall (23) of the receiving recess, as in No. 70820. Also when pouring, the flow of the silver brazing on the bottom surface (31c) of the central part of the cutting edge tip is improved, and the gap may be filled by pouring the silver brazing directly from the gap as described above.

In the embodiment, the left and right guide portions are projected rearward from both the left and right side portions, but they can also be projected forward.
In this case, the portion of the tip of the blade tip that protrudes forward may be scraped off during the final polishing of the blade tip, whereby a blade edge similar to a normal one can be made to appear. Further, the left and right guide portions may be guides for lateral positioning, and do not necessarily have to be provided over the entire length of the cutting edge tip. Furthermore, the protruding length of the cutting edge tip is free, and the protruding length of the cutting edge tip may be adjusted by polishing the saw base metal (1) as shown by the dotted line in FIG.

In addition to the above, the shape of the cutting edge tip can be variously changed, and in addition to the circular saw, the present invention can be applied to a hole saw that forms a cutting blade at a cylindrical tip and cuts a circular hole.

As the material of the base metal of the cutting blade used for the above circular saw, hole saw, etc., carbon tool steel, alloy tool steel, aluminum alloy and other non-ferrous metals are used, and the cutting edge tip is made of cemented carbide, CBN, cermet ceramic, Various materials developed to enhance cutting ability such as glass can be used.

<Effect of the Invention> As described above, in the present invention, the gap between the bottom surface of the central portion and the bottom wall of the receiving recess, which occurs when the cutting edge tip is not fitted to the predetermined depth, is covered by the bottom guide surface of the bottom guide portion. It becomes a state. This can prevent and improve the flow of silver braze or adhesive, and if the silver braze or adhesive is poured into the gap from the side where the bottom guide does not extend, the gap will be covered by the bottom guide surface. Therefore, the gap does not flow out and the gap can be filled, and the bottom surface of the central portion of the cutting edge tip and the bottom wall of the receiving recess can be reliably joined. Therefore, the present invention can provide a cutting blade capable of completely preventing the cutting edge tip from coming off.

[Brief description of drawings]

FIG. 1 is a side view of a main part of a cutting blade of one embodiment, FIG. 2 is a perspective view of a cutting edge tip of the same embodiment, and FIGS. 3 (A) and (B) are front views of cutting edge tips of the same embodiment, respectively. 4 (A) and 4 (B) are plan views of the cutting edge tip of the same embodiment, FIGS. 5 (A) and 5 (B) are rear views of the cutting edge tip of the same embodiment, and FIG. 6 (A) ( B) is a bottom view of the cutting edge tip of the same embodiment, FIGS. 7 (A) and (B) are right side views of the cutting edge tip of the same embodiment, and FIGS. 8 (A) and (B) are the same embodiment, respectively. Fig. 9 is a left side view of the blade tip of Fig. 9, Fig. 9 is a sectional view taken along line IX-IX in Fig. 1,
FIG. 10 is a sectional view taken along line XX of FIG. 1, and FIG. 11 is a side view of a main part of a cutting blade of another embodiment. (1) ... Base metal, (2) ... Receiving recess, (3) ... Blade tip, (5) ... Small hole, (21) ... Front wall, (22) ... Rear wall, (23) ... Bottom wall, ( 31) ... central part, (31a) ... central part front surface, (31b) ... central part rear surface, (31c) ...
Bottom of center part, (32) ... left side part, (33) ... right side part, (34) ... left guide part, (34a) ... left guide surface, (35) ... right guide part, (35a)
... right guide surface, (36) ... bottom guide part, (36a) ... bottom guide surface, (38) ... tip surface, (39) ... gap, (H) ... horn.

Claims (1)

[Scope of utility model registration request] 1. A cutting blade comprising a base of a cutting edge tip fixed to a receiving recess formed in a base metal, and a central portion into which the base of the cutting edge tip is fitted in the receiving recess.
One of the left and right side portions formed on both sides of the central portion and protruding in the thickness direction of the base metal, the left and right guide portions protruding at least rearward from the left and right side portions and contacting the side surfaces of the base metal, and the left and right side portions. And a bottom guide portion that comes into contact with the side surface of the base metal below the receiving recess and projects downward from the bottom surface of the central portion.
A cutting blade having a cutting edge tip, characterized in that the cutting edge tip is adhered to a base metal in a state where a gap formed between the bottom surface of the central portion and the bottom wall of the receiving recess is covered by the bottom guide portion.