JP2016068176A - Saw blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a saw allowing a person such as a housewife who is not familiar with a use of a saw or a cutter knife to dissection a cardboard box to shred into small pieces, which case is increasing these days, to perform cutting operation smoothly with a small power without causing an injury with a reduced amount of chips produced during cutting operation.SOLUTION: A saw comprises a blade plate provided with a plurality of V-shaped notches arranged at appropriate intervals on a horizontal part of an edge part of the blade plate with a tip tapered off in thickness toward a tooth tip end.SELECTED DRAWING: Figure 2

Description

The present invention relates to a structure of a saw blade for a hand saw that is particularly suitable for cutting a corrugated cardboard or foam plastic plate.

  Hand saws typically cut wooden boards, but they are also called pruning, suitable for cutting raw wood, bamboo cutting, plastic pipe cutting, thin metal Various saws specialized for cutting objects, such as those for cutting plates, have been proposed and are actually sold. That is, it is almost a situation that there exists a saw suitable for them depending on what is to be cut.

  Among them, there is a “cardboard box”. Cardboard boxes are frequently used as packaging materials for home appliances, and are also mainstream as packages for home delivery packages, so they are usually discarded after unpacking. In addition, there is a local government that recommends dismantling to a compact size, especially in urban areas, and it can be said that more and more housewives are dismantling. Corrugated cardboard packaging boxes may contain foamed polystyrene as a buffer, but this is also the case for dismantling in a compact size.

In other words, there is an increasing situation where housewives who are not accustomed to using saws and cutter knives have to dismantle the cardboard boxes and chop them into small sizes (for example, within 50 cm).
Therefore, an instrument that can smoothly perform the cutting operation even if it is weak is desired.
In addition, there is a need for an instrument that is safe enough to prevent cuts from being used by those who are not familiar with it.
Furthermore, since the cutting and dismantling work is not performed in a dedicated work place, an instrument that does not generate much chips is desired wherever it is performed in the room.

By the way, it was not the case that there was no “cardboard box dismantling instrument” so far. For example, in the invention described in Japanese Patent Application Laid-Open No. 7-8641, a cutter suitable for cardboard cutting by measures such as forming the saw blade as narrow as the tip and forming the tip of each tooth in a flat shape. Has been proposed.

JP-A-7-8641

However, what is proposed here is that the attachment part is mainly bent at the tip of the handle part, and a cutting blade having a sawtooth is provided on the attachment part, so that the cutting operation can be performed safely and quickly. However, there is insufficient consideration regarding the shape of the teeth.
The shape of the tooth is described only in the embodiment, and the saw blade is configured so that the width thereof becomes narrower toward the tip, and the thickness thereof becomes thinner near the tip. The tooth itself is merely described as “formed in an arc shape and flat portions 5b and 6b are formed at the tip portions of the tooth tips 5a and 6a”.
Judging from the drawings, the teeth on the circular arc are arranged in zigzag and alternately on both side end faces of the saw blade, and do not protrude from both side planes (in other words, there is no “claw”).

That is, the idea is that safety is ensured by flattening the tip of the tooth to be touched with a finger. Since the teeth are arranged alternately as shown in FIG. 10, when trying to improve the sharpness, it is necessary to sharpen the teeth in the arc shape except for the tip portion, which is safe. It means that sex will be damaged.

In addition, the teeth are not arranged on a straight line, but are arranged alternately on two parallel straight lines (that is, in a zigzag manner), which means that the traces are not beautiful and chips are generated. Means. Therefore, although the point of ensuring safety can be eliminated, an ideal instrument has not been sufficient.

  Therefore, in view of these points, the present inventor finally made the present invention as a result of earnest research in search of an instrument that is safe, has beautiful cuts, and generates almost no chips. However, V-shaped notches are provided at appropriate intervals in the horizontal portion of the blade tip portion where the thickness of the blade at the tip of the saw plate becomes thinner as it approaches the tip of the cutting teeth.

Here, the “saw blade” is one of the members constituting the hand saw, and is fixed to the saw handle. Since the replaceable blade type is prevalent, the present inventor has also researched and developed based on this, but the present invention is not limited to this, and is for a fixed saw (a saw not premised on replacement of the saw blade). A saw blade may be used.
In the present specification, the “saw blade” and its “tooth” are clearly distinguished. The saw is formed by making zigzags on one side surface (both side surfaces in the case of a double-edged saw) of a saw plate as a material, and thus a single-edged saw or a double-edged saw is completed. The individual chevron portions constituting the zigzag contribute to cutting, and are called “saw teeth” or “saw teeth”. The whole (tooth row) formed by the saw blade is a “blade”. Then, in the case of a knife that does not have “tooth” such as a kitchen knife or a cutter knife, a ridge line portion that is sharpened by reducing the material thickness toward the tip is called a “blade”.
The present invention is a structure having both a saw-like element and a cutter-knife-like element, and while having a “blade” as a ridge line portion whose material thickness is thinned toward the tip and sharpened to some extent, It can be said that it also has “teeth”.

  The saw blade according to the present invention has a cutter knife-like blade and teeth like a normal saw, but the teeth are not composed of repeated zigzags as a whole. V-shaped notches and straight lines are alternately repeated. In other words, a conventional saw tooth basically has a set-up, which is strictly speaking that the tooth row is arranged on two straight lines instead of one straight line, and the cutting operation is performed on the two straight lines. It can be said that the cutting teeth alternately arranged on the top scrape off the object to be cut. Therefore, at least a portion sandwiched between the two straight lines becomes chips. In addition, since it is cut out in a zigzag pattern, the traces are not as beautiful as when cutting in a straight line.

  That is, according to the present invention, a V-shaped notch is provided at an appropriate interval on a blade whose tip is thin and sharp like a knife, and there are four edges in this notch (strictly speaking, four per notch). Can be said to contribute to the cutting of cardboard boards, cardboard boxes, foamed plastic boards, etc. (hereinafter referred to as cardboard etc.).

  In the present invention, the corrugated cardboard cutting mechanism is such that a “horizontal portion” that opens and shears like a knife blade and a “notch portion” that shears while breaking like a saw tooth alternate. It is. Unlike the ordinary saw blade, the notch portion is present at the tip portion where the thickness of the blade plate becomes thinner toward the tip, so the “width (thickness)” is very narrow. With a normal blade, notches are formed without changing the thickness of the blade plate, and each tooth is alternately tilted outward to form a clam, so the substantial “width (thickness)” is extremely high. Big. Therefore, in the present invention, the amount of generated chips is extremely reduced.

Further, when cutting is performed depending on only the sharpness of the blade like a knife, it becomes difficult to cut after the sharpness of the blade itself, that is, the so-called sharpness is lost. And unfortunately the time to lose sharpness is very short.
However, in the case of the present invention, the low cutting ability in the horizontal portion can be sufficiently covered in the notched portion, so that the cutting of the horizontal portion is not inferior and cutting is not difficult. Therefore, even if the tip of the horizontal portion is flat or rounded, it can be used. And the thing which the tip of the horizontal part is flat or round is excellent in safety because it does not break even when touched.

  Further, when the shearing is performed, the narrow width (thickness) means that there are few parts that destroy the cardboard and the like, and the cut becomes beautiful.

  In the saw blade of the present invention, the cutting is performed by moving back and forth while pressing it in a state of being applied at an acute angle (for example, 45 degrees) with respect to the surface of the plate to be cut, such as cardboard, in the same manner as a normal saw blade. There is no particular limitation on whether to cut or push, but within the range that the present inventors have experimented, the workability was good when the V-shaped notch was made into an isosceles triangle and pushed and cut.

Further, the depth and length of the notch portion and the length of the horizontal portion are closely related to cutting ability, chip amount, safety, and the like.
If the notch is deep and long, the cutting ability is increased, but the amount of generated chips is also increased. As the horizontal section becomes shorter, the cutting ability increases but the danger increases. As a result of experimental investigation, considering the cutting ability, amount of chips, safety, etc., the width of the V-shaped notch is 0.2 to 2.0 mm and the depth is 0.2 to 2.0 mm. And the width of the horizontal portion is 1.0 to 3.0 mm, which is extremely suitable. However, these numbers do not immediately limit the present invention.

The saw blade of the present invention is not only provided with the claws provided for ordinary saw blades, but the blade is thin and sharp toward the tip, so that cutting of cardboard and the like proceeds. Accordingly, the frictional force between the cardboard and the saw blade surface increases. Therefore, in terms of reducing frictional resistance, it is more convenient to use a narrow and tapered saw plate than a wide and parallel saw plate. Alternatively, it is more effective to apply a coating treatment of polytetrafluoroethylene on the front and back surfaces of the saw plate.

The saw blade according to the present invention is a blade tip portion whose thickness becomes thinner toward the tip of the incisor, and the blade tip portion is provided with V-shaped cutouts at appropriate intervals. This is an extremely advanced invention having the following effects.
(1) Unlike typical saw blades, there are no claws, and unlike typical saw blades, the cutting edge is gradually thinner and sharper, and the cutting teeth are in a straight line, so there is almost no chips. Does not occur.
(2) Since cutting is not hindered even if the blade of the horizontal portion is not sharp, it can be used safely even by women and girls who are unfamiliar with handling.
(3) The edge portion that contributes to the cutting in the cutout portion is a ridgeline of two surfaces that are substantially perpendicular, so that the sharpness is less likely to be lost compared to a cutter knife or the like. Therefore, it can be used for a long time without care.

It is a schematic plan view which shows an example of the saw blade concerning this invention. It is a general | schematic partial expansion perspective view of an example of the saw blade which concerns on this invention. It is a schematic plan view which shows the state attached to the saw handle of an example of the saw blade which concerns on this invention.

FIG. 1 shows an example of a saw blade 1 according to the present invention (hereinafter referred to as “the present invention saw blade 1”), and the present invention saw blade 1 of the present example is of a replaceable blade type.
As apparent from the figure, the saw blade 1 of the present invention has a thickness of about 0.7 mm and a blade span of about 220 mm. The saw width is about 30 mm at the maximum at the hand portion, and gradually becomes narrower from here toward the top side.
In addition, the saw blade is provided with a blade portion 2 having a width of about 2 mm over one end thereof, and the saw plate, which is a flat plate having a thickness of about 0.7 mm, gradually becomes thinner like a knife or a cutter knife at this portion. Has reached. However, it is not as sharp as a normal knife or cutter knife, and it cannot be cut as long as it is traced with a fingertip.

FIG. 2 is a partially enlarged view of the saw blade 1 of the present invention. The blade portion 2 is intermittently provided with V-shaped cutout portions 4 so that the horizontal portions 3 and the cutout portions 4 exist alternately.
In this example, the length a of the horizontal portion 3 is about 1.5 mm, and the notch 4 has a length b of about 1 mm and a height c of about 1 mm.

The four edges 41 that form the cutout 4 contribute most to the cutting of corrugated cardboard or the like, and the cutting ability of the horizontal portion 3 is not so high, and the horizontal portion 3 is present in the cutout portion. Therefore, it may be said that it plays a role of accurately guiding to the adjacent notch 4.

FIG. 3 shows a state in which the saw blade 1 of the present invention is attached to the saw handle 5. When cutting corrugated cardboard or the like with this saw, the blade is basically moved back and forth as in a normal sawing operation, but the saw blade slides at the horizontal portion 3 and cuts at the notch 4 portion. It will be. However, the worker only recognizes as a feeling of vibration and cannot feel it with the recognition of “sliding” or “cutting”. The unique sensation obtained when cutting forwards is different when cutting with a cutter knife or when sawing, and tears perforated paper or stamp sheets along perforations or perforations. It is a feeling that is sometimes obtained, and it is extremely fresh and comfortable.

DESCRIPTION OF SYMBOLS 1 Saw blade which concerns on this invention 2 Blade part 3 Horizontal part 4 Notch part 41 Edge 5 Saw pattern

Claims (4)

A saw blade characterized in that V-shaped notches are provided at appropriate intervals in the horizontal portion of the blade edge portion where the thickness of the blade at the tip of the saw plate becomes thinner as it approaches the tip of the cutting teeth. The saw blade according to claim 1, wherein the width of the blade becomes narrower from the saw handle side toward the saw tip side. The saw blade according to claim 1 or 2, wherein the V-shaped notch has a width of 0.2 to 2.0 mm, a depth of 0.2 to 2.0 mm, and a horizontal portion has a width of 1.0 to 3.0 mm. . The saw blade according to claim 1, 2 or 3, wherein the horizontal portion has a flat or rounded tip.

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