JPS63167718A - Circular saw - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a circular saw in which a cemented carbide cutting edge tip is joined to saw teeth formed on the peripheral edge of a disc-shaped steel side body.

BACKGROUND OF THE INVENTION Conventional techniques and their problems For example, circular saws for mowing grass have conventionally had saw teeth formed on the peripheral edge of a disc-shaped steel side body. However, steel saw teeth have low wear resistance and wear out quickly, resulting in an extremely short service life. For this reason, circular saws have come to be used in which one cemented carbide cutting edge tip is joined to each saw tooth formed on the peripheral edge of the steel side body. The steel saw blade itself bends easily even if it collides with a stone, etc. This absorbs the impact, making it less likely to break. However, by bonding extremely rigid cemented carbide cutting tips to these steel sawtooths, the overall rigidity of the sawtooth increases, making it less likely to bend, making the cutting tips more likely to chip when they collide with stones, etc. There's a problem.

An object of the present invention is to solve the above-mentioned problems and provide a circular saw with a cemented carbide cutting edge that is hard to chip and has a long life.

Means for Solving the Problems The circular saw according to the present invention has a cemented carbide cutting edge tip bonded to the saw teeth formed on the peripheral edge of a disc-shaped steel side body, and has the following features: It is characterized by the thickness of the end portion being thinner than the other portion.

By bonding the superalloy cutting edge tip to the working sawtooth, this part becomes more rigid, but because the thickness of the base end of the sawtooth is thinner than the other parts, the sawtooth becomes more susceptible to deflection. Therefore, even if the tip collides with a stone or the like during use, the serrations easily bend, which absorbs the impact, making the cutting edge less likely to chip.

Example Hereinafter, the present invention will be described in detail with reference to the drawings.

In this specification, front, rear, left, and right refer to the moving direction of the cutting edge tip during cutting, and the outside refers to the outside in the radial direction of the side body.

Figure 1 shows a part of a circular saw for mowing grass, in which a plurality of saw teeth (11) formed on the periphery of a disk-shaped hardened steel saw body (10) have a cemented carbide cutting edge. Chips (12) are attached one by one.

The tip (12) can be attached to the sawtooth (11) in any way, but for example, it is as follows.

One approximately U-shaped chip mounting notch (13) facing outward and diagonally forward is formed in the front part of each sawtooth (II) of the side body (10), and the approximately rectangular parallelepiped chip (12) It is inserted into this groove (13) and joined by brazing. Further, the top surface and the upper front surface of each chip (12) are polished, and a cutting edge (12a) is formed between the top polished surface and the front polished surface.

A notch (14) is formed at the rear of the proximal end of each serration (11) of the side body (10), and the longitudinal width of this portion is smaller than that of the other portions. Further, the thickness of the proximal end of the 6 saws (11) is thinner than the other parts. Although the method of thinning this part is arbitrary, for example, by polishing or the like, a shallow circular groove (15) concentric with the side body (IO) is formed on both sides or one side of the base end of the sawtooth (11). By doing so, this part can be made thinner.

By joining the extremely rigid superalloy cutting edge tip (12) to the saw tooth (11), the rigidity of this part is increased, but the front and back width and thickness of the base end of the saw (11) are different from other parts. The smaller size makes the sawteeth (11) more flexible. Therefore, even if the tip (12) collides with a stone or the like during use, the sawtooth (11) easily bends, thereby absorbing the impact, so that the cutting edge tip (12) is less likely to chip. In addition, even if the base end of the sawtooth (11) is made thinner,
effective.

This invention can of course be applied to circular saws other than those for mowing grass.

Effects of the Invention According to the circular saw of the present invention, the thickness of the base end of the saw teeth on the steel side body is thinner than the other parts, so even if the cemented carbide cutting tip is bonded. Regardless, the serrations become easily bent, and the cutting edge tip becomes less likely to chip.

Moreover, since the cutting edge tip is made of cemented carbide, which is hard and has high wear resistance, it has a longer lifespan than conventional ones.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a side view showing a part of a circular saw for mowing grass, and FIG. 2 is an end view taken along line nn in FIG. 1. (lO)...Side body, (11)...Sawtooth, (12)
...Blade tip. or more y) 4″6

Claims (1)

[Scope of Claims] A circular saw in which a cemented carbide cutting edge tip (12) is joined to saw teeth (11) formed on the peripheral edge of a disc-shaped steel saw body (10), comprising: saw teeth (11); ) is characterized in that the thickness of the base end is thinner than the other parts.