JPH01316123A - Circular saw having cemented carbide cutter - Google Patents

Abstract

PURPOSE:To dissolve stress concentration without reducing the strength of a substrate by carrying out polishing after forming a linear impression in the radial direction between the tips of a disc-shaped substrate made of steel on the outer periphery of which a plurality of superhard tips are soldered. CONSTITUTION:When a circular saw cutter is soldered, a cemented carbide tip 2, solder 3, and the steel of a substrate 1 are put into high temperature, and expanded with each characteristic thermal expansion rate, and in cooling, the stress concentration is generated at the soldered part on the basis of the difference of the thermal expansion rate, and a tip 2 having the smallest thermal expansion rate is applied with a pulling force. The stress concentration can be dissolved by forming an impression 5. Therefore, no warp due to stress concentration is generated on the circular saw cutter, and also the tip 2 is not applied with a pulling force due to the stress concentration, and the superior polishing is permitted. Further, though the tip 2 possesses a high resistance force for a compression force, the tip 2 possesses weak property for a pulling force. Therefore, when polishing is performed in the stress concentration state, a crack is generated on the tip 2 applied with pulling action, but the polishing free from crack is permitted because polishing is carried out after the stress concentration is dissolved by the impression 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a circular saw blade with a carbide edge used for cutting or grooving metal materials.

[Prior art] A circular saw blade with a carbide blade is formed by brazing a carbide tip made of carbide metal or a carbide pressure tip such as artificial diamond onto the outer periphery of a steel disc-shaped substrate, and then polishing the same. It had been. In addition to holes for attachment to the cutting machine, punched holes are bored in the substrate near the area where the chips are to be soldered. This punched hole is provided in order to eliminate stress concentration that occurs at the part where the chip is soldered.

That is, as shown in FIG. 5, a plurality of chips 100 are brazed and fixed at predetermined positions on the outer periphery of a steel disc-shaped substrate 101. During this brazing, the chip 100, the substrate 1
01 and the brazed member 102 reach a high temperature and have unique thermal expansion coefficients that are significantly different from each other. stress concentration occurs. This stress concentration causes a tensile force to act on the chip 100, which has the smallest coefficient of thermal expansion, and when polished in this state, the chip 100
This results in problems such as cracks 103 occurring in the substrate 00 and warping of the substrate 101. Therefore, in the past, 100 chips were used.
After soldering, the above-described punched holes were punched in the substrate 104 to eliminate the above-described stress concentration.

[Problems to be Solved by the Invention] However, punching holes in the substrate of a circular saw blade is not preferable because it significantly reduces the strength of the substrate.
In particular, circular saw blades with small diameters and thin substrates have a problem in that the required strength required for circular saw blades cannot be obtained.

The present invention was made in view of the above-mentioned circumstances, and its purpose is to provide a steel disc-shaped substrate without reducing its strength.
To provide a circular saw blade with a carbide blade that eliminates stress concentration that causes damage to the carbide tip and warping of the board.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method of forming linear indentations in a substantially radial direction between the chips of a steel disc-shaped substrate having a plurality of carbide chips brazed on the outer periphery. It is characterized by being polished.

As the carbide tip, a carbide metal tip or a carbide pressure tip can be used.

[Function] Since the present invention is configured as described above, when brazing a carbide tip or a carbide pressure tip, the tip, solder, and steel (substrate) each have their own coefficient of thermal expansion. Since it expands and contracts, this difference in thermal expansion causes stress concentration in the part after brazing, but this stress is relieved by the linear indentations made on the substrate between the chips. Ru.

[Example] The present invention will be specifically described below based on an illustrated example.

1 and 2 are a front view and a cross-sectional view of a circular saw blade with a carbide edge according to the present invention, in which a plurality of carbide tips 2°2 made of cemented carbide are disposed on the outer periphery of a steel disc-shaped substrate 1. ...is fixed. As shown in FIG. 3, the tip 2a of the carbide tip 2 is formed with a flank face a and a rake face, and the flank face a and the rake face intersect at an acute angle to form a cutting edge C. is formed, and the rear end portion 2b is formed to have a rectangular cross section, so that the overall shape of the carbide tip 2 is approximately prismatic. As the carbide tip 2, a carbide pressure tip may also be used. This carbide tip 2 has a recess 1a formed on the outer periphery of the substrate 1.
It is fitted from the rear end portion 2b side, and this fitting portion is fixed with solder 3 such as silver solder. Further, a part of the outer periphery of the substrate 1 is cut out continuously from the above-mentioned recess 1a to form a sloped surface 1b, and this sloped surface 1b is used to remove chips as well as the swing surface of the fixed carbide tip 2. An escape groove 4 is formed.

Furthermore, indentations 5.5... are formed on this circular saw blade. After the carbide chips 2 are brazed and cooled, the indentations 5 are provided on the substrate 1 between the plurality of carbide chips 2, 2, . . . in a substantially radial direction. This indentation 5 is provided so that one end reaches the escape groove 4 and the other end reaches inside the substrate 1 so as to be at least sufficiently longer than the length of the carbide tip 2. In this embodiment, the length of the indentation 5 is the tip 2.
It is approximately twice as long as the The impressions 5 are formed by applying a jig to the front and back surfaces of the substrate 1, as shown in FIG. That is, FIG. 4(a) shows an acute knife edge 6.
Indentations 5 are formed on the front and back surfaces of the substrate 1 by simultaneously pressing the jigs 6 and 6 having the jigs a and 6a from the front and back surfaces of the substrate 1. FIG. 4(b) shows an example in which jigs 7, 7 having obtuse knife edges 7a, 7a are used in place of the above-mentioned jigs 6.6, and FIG. 4(c) shows a flat plate on the back surface of the substrate 1. 8 and presses the jig 6 against the surface to form an indentation 5 on the surface of the substrate 1. The above-mentioned knives 6a and 7a are the fourth
In addition to being sharply formed as shown in the figure, they may also be somewhat rounded. In this way, the indentations 5 may be provided on both the front and back surfaces of the substrate 1, or may be provided only on one side, and since deep grooves are not provided, even when a thin substrate 1 is used, its strength can be maintained sufficiently. can be secured.

The thus formed circular saw blade can then be polished to form a finished circular saw blade. Incidentally, in FIG. 1, the perforations 9, 9, . . . provided in the substrate 1 are mounting holes for mounting on a cutting machine or the like.

By forming the circular saw blade in this way, during brazing, the carbide tip 2, the solder 3, and the steel of the substrate 1 reach a high temperature, and each thermally expands with its own coefficient of thermal expansion. Stress concentration occurs in brazing parts due to differences in thermal expansion coefficients, and the carbide tip 2 with the smallest thermal expansion coefficient receives tensile force, but by providing the indentations 5, the above stress concentration can be eliminated. .

Therefore, the circular saw blade does not warp due to the above stress concentration, and the carbide tip 2 is not subjected to tensile force due to the above stress concentration, so that good polishing can be performed. The carbide tip 2 has a high resistance against compressive force, but has a property of being weak against tensile force. Therefore,
When polished in the state of stress concentration, the carbide tip 2 subjected to the action of tensile force cracks, but in the present invention, since the stress concentration is eliminated by the indentations 5 before polishing, the carbide tip 2 cracks. It can be polished without any problems.

[Effects of the Invention] Since the present invention is configured as described above, stress concentration in the brazing portion of the carbide tip can be eliminated without reducing the strength of the steel substrate that holds the tip. As a result, it is possible to obtain a highly accurate circular saw blade with a carbide blade that has sufficient substrate and chip strength and is free from warping.

[Brief explanation of the drawing]

FIG. 1 is a front view of a circular saw blade with a carbide blade according to the present invention, FIG. 2 is a sectional view taken along the IT-TI line in FIG. 1, and FIG. 3 is a
FIGS. 4A, 4B, and 4C are explanatory views of the indentation forming means of the present invention, and FIG. 5 is an enlarged view of the main parts of a conventional circular saw with a carbide blade. 1... Steel disc-shaped substrate, 2... Carbide tip, 3...
・Row, 5...indentation. Patent Applicant: Masuda Seiki Co., Ltd. t, -,':t''-No. Related Patent Applicant Address Name Name Masuda Seiso Co., Ltd. 4 Agent 5 Date of Amendment Order Voluntary [Contents of Amendment (1) Substrate 104” on page 2, line 15 of the specification has been replaced with “substrate 101.” ” he corrected. (2) Correct the drawings in Figures 3 and 4 (b) as shown in the attached sheet. Above-1,25-

Claims (1)

[Claims] (1) A circular saw blade with a carbide blade, characterized in that a steel disc-shaped substrate having a plurality of carbide tips brazed on its outer periphery is polished with linear indentations formed approximately in the radial direction between the tips. .