JPH08229735A - Chip saw - Google Patents

Abstract

PURPOSE: To perform accurately positioning a chip in a recessed part so as to obtain sufficient brazing strength, by forming the recessed part in almost triangular shape widening a breadth toward a center side from a peripheral edge side of a round saw material to have a right angle part in a bottom surface side, and bringing a right angle part of the almost right angled triangular shaped chip into contact with the right angle part of the recessed part. CONSTITUTION: A chip 5, fixed by brazing to a recessed part 6, is formed into a right angled triangular shape as viewed by plane, to have three side surfaces 5a to 5c. In this chip 5, corresponding to a shape of the recessed part 6, a crossing angle of the side surfaces 5a and 5c is a right angle, to set a width of the side surface 5c almost equal to or slightly smaller than a width t2 of a bottom surface 6c. Each side surface 5a to 5c of the chip 5 is formed straight in a plate thickness direction. Since a right angle part is respectively formed in the recessed part 6 and the chip 5, only by bringing the right angle part of the chip 5 into fitting contact with the right angle part of the recessed part 6, positioning can be accurately performed, and the chip 5 can be fixed by brazing to a prescribed position of the recessed part 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tip saw in which a tip is brazed and fixed in a concave portion of a peripheral edge of a circular saw material.

[0002]

2. Description of the Related Art Conventionally, as a tip saw used for cutting grass, cutting wood, etc., for example, the one disclosed in JP-A-6-344221 has been proposed by the present applicant. In this tip saw, for example, a taper-shaped substantially triangular concave portion that spreads from the outer peripheral side toward the center side is formed in the peripheral portion of a disk-shaped circular saw material, and a substantially equilateral triangular tip is formed in the concave portion. It is brazed and fixed.

[0003]

However, in this tip saw, compared to the conventional tip saw, the tip saw is prevented from coming off from the concave portion of the tip, but the tip is accurately and sufficiently strong at a predetermined position of the concave portion. There was a problem that it was difficult to braze. That is, for example, when the tip is formed into an equilateral triangle shape and the tip is fitted into the substantially triangular concave portion of the circular saw material, it is difficult to form the angle of the corner portion with high precision, and the reference surface is It is difficult to accurately set the chip at a predetermined position of the recess because it is not specified and the dimensional variations of the recess and the chip easily occur.

Further, even if the brazing material is brought into contact with the fitting portion that is induction-heated due to the variation in the set position of the chip, the brazing material does not flow well along all the fitting surfaces, and the brazing strength is increased. Variations easily occur and it is difficult to obtain sufficient brazing strength.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a tip saw capable of accurately positioning a tip in a recess and obtaining sufficient brazing strength.

[0006]

In order to achieve the above object, the tip saw according to claim 1 is one in which a plurality of recesses are formed in the peripheral edge of a circular saw material, and the tips are brazed and fixed in the recesses. In the above, the concave portion is formed in a substantially triangular shape having a wide portion from the peripheral side of the circular saw material toward the center side and having a right-angled portion on the bottom surface side, and the chip is formed in a substantially right-angled triangular shape. Is fitted in the recess from the plate thickness direction, and the right-angled portion of the chip is brought into contact with the right-angled portion of the recess to be brazed. A tip saw according to a second aspect of the invention is characterized in that the opening of the concave portion is positioned such that the edge of the tip saw on the rotation direction side is located inside the edge on the opposite side of the rotation direction.

[0007]

According to the tip saw of the first aspect, the substantially right-angled triangular tip is fitted from the plate thickness direction of the circular saw material, in which case the right-angled portion as the reference portion of the tip is recessed. The chip is accurately positioned and set in a predetermined position of the recess by abutting on the right angle part of the. Further, the right-angled portion having an angle larger than the acute angle allows the molten brazing material to flow well on both sides of the right-angled portion, so that the chip is firmly brazed and fixed in the recess. Further, according to the tip saw of claim 2,
By positioning the opening edge on the rotation direction side of the tip saw on the inner side of the counter rotation direction side, the tip of one side of the right angle portion of the tip can be a cutting edge having a sufficient length.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a plan view of a tip saw according to the present invention. In FIG. 1, a tip saw 1 has a disk-shaped circular saw material 2 formed by pressing a steel plate material. A mounting hole 3 is formed at the center of the circular saw material 2, and a plurality of chips 5 are provided at its peripheral edge 4.
Are brazed and fixed at equal intervals in the circumferential direction.

The chip 5 is, as shown in FIGS. 2 and 3,
It is brazed and fixed to a plurality of concave portions 6 formed at equal intervals on the peripheral portion 4. The recessed portion 6 is formed in a generally right-angled triangular shape that is tapered toward the center (toward the attachment hole 3) from the peripheral edge of the circular saw material 2.
The width t2 of the bottom surface 6c located on the center side is set to be larger than the width t1 of the opening 7 on the peripheral side (opening end portions of both side surfaces 6a and 6b of the recess 6).

The crossing angle between the bottom surface 6c of the recess 6 and the side surface 6a is formed at a right angle (90 degrees), and the edge of the opening 7 of the recess 6 on the side surface 6a side is the end on the side surface 6b side. It is located inside the dimension t3 from the edge. Both side surfaces 6a, 6b and the bottom surface 6c of the recess 6 are formed straight (vertical) in the plate thickness direction.

A chip 5 brazed and fixed in the recess 6
Are formed in a right-angled triangle shape in a plan view and have three side surfaces 3a ...
3c. The tip 5 corresponds to the shape of the recess 6, the side surface 5a and the side surface 5c intersect at a right angle, and the width t3 of the side surface 5c is set to be substantially the same as or slightly smaller than the width t2 of the bottom surface 6c of the recess. Also, each side surface 5a of the chip 5
5c are formed straight in the plate thickness direction. When the tip 5 is fitted into the recess 6 as described later, for example, the tip portion 8 which is the intersection of the side surfaces 5a and 5b protrudes from the outer peripheral edge of the circular saw material 2 by a predetermined length, and the tip saw 1
Is formed.

The tip saw 1 is manufactured, for example, as follows. That is, first, the circular saw material 2 formed into a predetermined shape is set in a substantially vertical state as shown in FIG. 4, and the concave portion 6 of the circular saw material 2 is provided with one side surface (the thickness direction of the circular saw material 2). The chip 5 is fitted from one side). At that time, the recess 6
The side surface 5a, which is one side of the right-angled portion of the chip 5, is placed on the side surface 6a, which is one side of the right-angled portion, due to its own weight. In this state, by pushing the chip 5 toward the bottom surface 6c of the recess 6, the side surface 5c contacts the bottom surface 6c,
The chip 5 is set in the recess 6.

After the chip 5 is set in the concave portion 6, a heating coil (not shown) is arranged in the vicinity of the fitting portion, and an inverter (not shown) is operated to heat the fitting portion by high-frequency induction heating, and the chain double-dashed line is shown. As shown by, the brazing material 9 is brought into contact with the fitting portion. As a result, the brazing material melts, and the molten brazing material 9 enters the gap between the recess 6 and the chip 5 by the capillary phenomenon. The invading brazing material 9 flows downward along the substantially vertical side surface 5c of the chip 5 as shown by the arrow a.
Then, it flows along the substantially horizontal side surface 5a. That is, the molten brazing material 9 flows by its own weight together with the capillary phenomenon, and the chip 5 is brazed to the recess 6.

When one chip 5 is brazed to the recess 6, the circular saw material is rotated in the direction of arrow B, and the chip 5 is brazed to the next recess 6 in the same manner as described above. By performing this work on all the concave portions 6 of the circular saw blank 2, the brazing work of the tip saw 1 is completed.

As described above, in the tip saw 1 of the above-described embodiment, since the right-angled portion is formed in the recess 6 and the tip 5, respectively, the right-angled portion of the tip 5 is simply fitted and abutted with the right-angled portion of the recess 6. Thus, the positioning can be accurately performed, and the chip 5 can be brazed and fixed at a predetermined position of the recess 6. Further, the right angle portion of the tip 5 and the concave portion 6 can be processed (manufactured) relatively easily, and the cost of the tip saw 1 can be reduced.

Further, the molten brazing material 9 flows by its own weight along the substantially vertical side of the right-angled portion in combination with the capillary phenomenon.
The flow of the brazing material 9 is improved, and the side surface 5a of the chip 5,
5c and at least 2 of the side surface 6a and the bottom surface 6c of the recess 6
The surface is surely brazed, and a sufficient brazing strength of the chip 5 is obtained. Further, the edge of the opening 7 on the side surface 6a side is
Since it is located inside the dimension t3 with respect to the edge on the side surface 6b side, the length of the cutting edge can be set to be large, and the sharpness of the tip saw 1 can be improved.

Furthermore, the opening 7 of the recess 6 has a bottom surface 6c.
Since the chip 5 having a substantially right triangle shape is fitted and brazed into the recess 6 which is formed to be narrower, the movement of the chip 5 in the direction of the opening 7 is surely prohibited. Even when an excessive force is applied to the tip portion 8 of the chip 5, the tip 5 does not drop from the recess 6. Therefore,
For example, even if there is a place where the brazing strength of the tip 5 is weak,
The tip 5 can be prevented from falling off with ease, the tip saw 1 can be used for a long period of time, and the tip 5 can be prevented from falling off and scattering, for example, the safety of mowing work is improved.

In the tip saw 1 described above, the bottom surface 6c and the side surface 6a of the recess 6 are formed at right angles, but the present invention is not limited to this, and is formed, for example, as shown in FIG. Good. That is, the tip saw 1 shown in FIG.
The bottom surface 6c and the side surface 6b are formed at a right angle, and an isosceles right triangle chip 5 is fitted into the recess 6 and brazed. Even with this configuration, in addition to the same effects as the above-described embodiment, the force with respect to the rotational direction C of the tip 5 can be received at the right angle portion, and the durability of the brazing strength of the tip 5 is improved. Can be made.

Further, in the above embodiment, the three sides of the recess 6 and the chip 5 are formed in a straight line. For example, as shown in FIG. 6, the bottom face 6c and the side face 6a of the recess 6 are in a straight line at right angles. In addition to the above, the side surface 6b may be curved, and the chip 5 having a curved side surface 5b and a substantially triangular shape as a whole may be fitted and fixed to correspond to the shape of the recess 6. By doing so, the tip portion 8 of the tip 5, which is the cutting edge, can be formed wide, and the durability of the cutting edge can be further improved.

Further, in the above embodiment, the chip 5
Although the side surfaces of the recess 6 and the recess 6 are formed straight in the plate thickness direction, for example, the side surfaces on both sides of the right angle portion of at least one of the chip 5 and the recess 6 may be tapered. With this configuration, when the chips 5 are set in the recesses 6, the setting positions of the chips 5 in the plate thickness direction can be made uniform, and the setting work of the chips 5 is further facilitated. in this case,
Of course, all surfaces of the fitting portion of the chip 5 and the recess 6 may be tapered surfaces.

The shapes of the recess 6 and the chip 5 in the above embodiment are not limited to those in the above embodiments, and the recess 6 having a right angled portion and having a substantially triangular shape, and the recess 6 are provided. It goes without saying that the chips 5 of all the above shapes are included.

[0022]

As described in detail above, according to the tip saw of the present invention, the chip can be fitted into the recess with reference to the recess and the right angle portion of the chip, and the chip is accurately positioned and set in the recess. In addition to the above, the right-angled portion has an effect that the flow of the molten brazing material becomes good, and the chip can be firmly brazed to the recess.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a tip saw according to the present invention.

FIG. 2 is a plan view of the main part.

FIG. 3 is an exploded perspective view of the main part.

FIG. 4 is an explanatory view of the brazing method.

FIG. 5 is a plan view of an essential part showing another embodiment of the tip saw according to the present invention.

FIG. 6 is a plan view of a main portion showing still another embodiment of the tip saw according to the present invention.

[Explanation of symbols]

 1 Tip Saw 2 Circular Saw Material 4 Peripheral Edge 5 Tip 5a, 5b, 5c Side 6 Recess 6a, 6b Side 6c Bottom 7 Opening 8 Tip 9 Brazing Material

Claims (2)

[Claims] 1. A chip saw in which a plurality of recesses are formed in the peripheral edge of a circular saw material, and chips are brazed and fixed in the recesses, the recesses being wider from the peripheral side of the circular saw material toward the center side. , Forming a substantially triangular shape having a right-angled portion on the bottom surface side, forming the chip in a substantially right-angled triangular shape, and fitting the chip into the recess from the plate thickness direction of a circular saw material, A tip saw, which is brought into contact with the right-angled portion of the recess and brazed. 2. The tip saw according to claim 1, wherein in the opening of the recess, the edge of the tip saw on the rotational direction side is located inside the edge on the anti-rotation side.