JP5350864B2 - saw - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such the problem that a saw structure in which a moving element enclosed inside a saw handle reciprocates when a saw blade is moved back and forth that ejects air intermittently from the saw blade side has some advantages but has a fatal problem in which the structure is only effective when the saw blade reciprocates in horizontal direction, and the moving element tends to collide with both ends inside the saw handle, causing colliding noise and a shock transmitted to a hand. <P>SOLUTION: The saw has a cylinder-like hollow portion formed inside the saw handle. A piston-like moving element is enclosed in the hollow portion, the tip of an air ejecting port facing the saw blade direction is formed at the end of the saw blade side of the hollow portion, and an air through-hole is formed at the opposite end of the hollow portion or the neighborhood position. The moving element is supported with an elastic body which is fixed to one end of the saw handle side. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

The present invention is a saw that removes the sawdust generated by sawing using a sawing operation, and functions not only when the sawing operation is horizontal but also in any direction including the vertical direction. It is about a saw.

When cutting wood, plywood, or the like with a hand saw, a cutting line is usually drawn in advance on the surface of the target wood (so-called “inking”). However, the ground powder always generated during the cutting operation tends to accumulate in the vicinity of the cutting line and hinder the accurate cutting operation. Then, the worker had to repeat the operation | work which blows on the ground powder accumulation location and exposes a cutting line.
This work is not only complicated, but is also done by bringing the face close to the accumulated ground powder, so if the target material is a kind of new building material, for example, harmful substances will be included in the dust. If it is, it will be sucked. This is serious for those who work long hours every day, and it can be said that the situation is unfavorable for health even if the frequency of work is similar to that of DIY.

  Therefore, the applicant previously proposed an invention as shown in Patent Document 1 as a measure for solving such a situation. This is because a hollow part is formed in the handle part, and a movable element that can move freely in the hollow part with the movement of the handle part is incorporated in the hollow part, and from the front part of the hollow part, It has a saw-tooth structure in which an air ejection port whose tip is directed in the direction of the saw blade is formed, and an air passage hole is formed in the rear portion of the hollow portion.

Because of this structure, when the saw blade is moved back and forth, the handle will reciprocate, and the mover in the hollow part will apparently move in the opposite direction to the direction of movement of the handle due to its moment of inertia. become. At this time, since the air in the hollow portion is fractionated by the moving element, when the moving element moves back and forth in the internal space, air is alternately discharged / sucked from the air outlet.

JP 60-137601 A

  When sawing with a saw having this handle structure, when the saw is reciprocated in the horizontal direction, the moving element generally oscillates in the hollow portion. However, the actual sawing operation is often not only a horizontal back-and-forth movement but also an oblique movement, and in some cases a vertical movement.

A typical example is a “grinding saw”. This saw is used for cutting a curve, drilling, etc., and usually has a narrow width and a thin wall. The saw cutting operation is basically in the vertical direction.
When the structure of Patent Document 1 described above is applied to a sawing operation typified by a sawing saw, the built-in moving element tends to descend in the hollow portion by its own weight. Therefore, when the amplitude of the reciprocating motion is small, the moving element stays at the lower end position of the hollow portion, and the amount of air discharged from the ejection port can hardly be secured.

Furthermore, the moving element that reciprocates in the hollow part has a structure that collides with both end positions of the internal space when sawing with a large stroke, and the user feels uncomfortable with the generated collision sound and the impact of the collision transmitted to the hand. Even a small number have confirmed.

  Therefore, in view of this point, the present inventor has finally completed an ideal structure as a result of earnest research, and the feature thereof is that a cylindrical hollow portion is formed inside the saw handle, and the hollow portion A piston-like moving element is built in, and an air blow-out port whose tip is directed in the direction of the saw blade from the end of the hollow portion on the saw blade side is provided at the opposite end of the hollow portion or in the vicinity thereof. A saw in which a through hole is formed, and the moving element is supported by an elastic body having one end fixed to the saw handle side.

  The present invention solves the problem that the movable element in the hollow part descends by its own weight and a sufficient amount of air discharged from the air outlet cannot be obtained, and the movable element collides with both ends of the hollow part. So that no loud sounds are generated. This can be achieved by supporting the moving element by an elastic body having one end fixed to the sawtooth side.

  The saw according to the present invention is a hand saw composed of a “saw blade” and a “saw handle”. Among these, regarding the “saw blade” portion, there is no limitation on whether or not it is a replaceable blade type, whether it is a double blade or a single blade, and so on. However, it can be said that it is particularly preferable when applied to a “grinding saw” because of its structural characteristics.

  The “saw pattern” has a “cylindrical hollow portion” formed therein. Since it is “cylindrical”, at least in the range of motion of the “moving element”, the cross section is equal and is not curved. In that sense, the appearance of the saw pattern is not preferable to a so-called “pistol-shaped” pattern, and a straight pattern is preferable.

  A “moving element” is built in the hollow cylindrical portion. This moving element is a piston-like member. That is, it is a member that reciprocates while sliding in the hollow portion, and that divides the internal space of the hollow portion into the saw blade side space and the other end side space by itself. However, it is not necessary that the two separated spaces are always cut off and hermetically sealed, and the air in the other end space can flow into the saw blade side space via the check valve structure (the saw blade side). The air in the space may not be moved to the other end side space).

  The cylindrical hollow portion is also provided with an “air blowout port” at one end (end portion of the saw blade side space) and an “air through hole” at the other end (near the end portion of the other end side space), Communicate with the atmosphere. Therefore, when the moving element moves to the saw blade side, the air in the saw blade side space is discharged to the outside from the air outlet. In the present invention, since the tip of the air outlet is oriented in the direction of the saw blade, when the saw blade generates saw dust during the cutting operation, the saw dust is blown off.

Conversely, when the moving element moves to the other end side (opposite to the saw blade side), basically, the air in the other end side space is discharged to the outside from the air outlet. However, in the case where the moving element is of a type having a valve structure, a part of the air in the other end side space also flows into the saw blade side space, so the amount of inflow from the air outlet is reduced. The fact that the amount of inflow from the air outlet is reduced means that it becomes difficult for the saw dust to enter the saw blade side space, and thus contributes to smooth sliding of the moving element over a long period of time.
An appropriate check valve structure may be disposed in the vicinity of the opening of the air ejection port so that outside air is not introduced into the saw blade side space via the port.

  In the present invention, the movable element incorporated in the hollow portion is supported by an elastic body having one end fixed to the sawtooth side. That is, either one (or both) of the both ends of the cylindrical hollow portion and the moving element are supported and connected by the elastic body.

  The form of “support” is a form in which the movable element is suspended from the top, a form in which the movable element is supported from the bottom, or suspended from the top when the longitudinal direction of the hollow portion is placed vertically. In addition, it may be supported from below.

Further, the details of the “elastic body” are not particularly limited. A rubber thread, a coil spring, or the like may be employed as appropriate.

The saw according to the present invention is an extremely advanced invention having the following effects.
(1) The ground powder inevitably generated on the wood in the hand saw can be blown away by using a hand grinding operation without requiring another power source.
(2) Since the conventional operation of blowing the face close is unnecessary, not only the workability is improved, but also the possibility that the operator sucks the sawdust is greatly reduced.
(3) Due to the presence of the elastic body that supports the built-in moving element, the saw is suspended in the hollow portion regardless of the position of the saw, and air necessary for discharge can be secured in the saw blade side space.
(4) Since the moving element is suspended, it is difficult to reach a situation in which the moving element collides with either end during reciprocating operation and an unpleasant noise is generated.

It is a schematic sectional drawing of an example of the saw which concerns on this invention. (A) (b) is all principal part sectional drawing which shows roughly the effect | action of the saw which concerns on this invention. It is a principal part schematic sectional drawing which shows the other example of this invention regarding the support form of a needle | mover. It is a principal part schematic sectional drawing which shows the other example of this invention regarding the structure of a needle | mover.

  FIG. 1 is a schematic cross-sectional view of an example of a saw 1 (hereinafter referred to as “present invention saw 1”) according to the present invention. As is apparent from the figure, the present invention saw 1 of this example is a replaceable blade type saw in a saw generally called a “grinding saw”, and is configured to be separated into a saw blade 2 and a saw handle 3. . Since it is a replaceable blade type, the saw blade 2 and the saw handle 3 are connected by the bolt 4, but the present invention is not limited to this, and a fixed integral type may be used.

  A hollow portion 5 is formed inside the saw handle 3, and a movable element 7 functioning as a piston is built in the hollow portion 5 so as to be suspended by a coil spring 6. Here, the upper and lower spaces fractionated by the movable element 7 are called a saw blade side space 51 and a second end side space 52, respectively. The saw blade side space 51 and the other end side space 52 are not hermetically sealed spaces. The saw blade side space 51 communicates with the atmosphere through the air outlet 53 and the other end side space 52 through the air passage hole 54. ing. Among these, since the air ejection port 53 is a nozzle-like pipe extending from the lower end of the saw blade side space 51, air is discharged toward the periphery of the saw blade 2 when air is discharged. In the state shown in the figure, the saw 1 of the present invention is stationary, and therefore the coil spring 6 is extended by the dead weight of the movable element 7, but the movable element 7 is also stationary and air does not enter and exit.

  The saw 1 reciprocates during the sawing operation. Since the present invention saw 1 in this example is a sawing saw, the sawing operation is basically performed along the vertical direction. In addition, taking a typical example of creating a circular hole, which is a typical operation using a sawing saw, the operation is as follows. First, the saw blade 2 is inserted into a hole H (such as a drill hole) previously engraved in the workpiece wood W. It starts from where you plug it. The state after insertion is shown in FIG.

Subsequently, the present saw 1 is pulled up. Since the mover 7 that slides on the inner wall of the hollow portion 5 and is suspended by the coil spring 6 has inertia derived from its own mass, the coil spring 6 is further extended by the acceleration at the time of lifting. This state is shown in FIG.
Compared with the state of FIG. 5A, the saw blade side space 51 is smaller, and the air originally in this space is discharged to the outside from the air outlet 53 in a form of being pushed out by the moving element 7. Then, outside air flows into the other end side space 52 from the air passage hole 54.
The raised saw 1 is then lowered, so that the coil spring 6 is now contracted from the state shown in FIG. 6A, and the inflow / discharge of air is opposite to the state shown in FIG. It will be made with.
Thereafter, during the sawing operation, the discharge and suction of air from the air ejection port 53 are repeated in such a manner that the moving element 7 moves up and down in the hollow portion 5.

  FIG. 3 shows another example of the present invention. In the examples so far, the movable element 7 is arranged in the hollow part 5 in such a manner that it is suspended from the upper part by the coil spring 6, but in this example, an elastic body is arranged in both the upper and lower sides. The elastic body may be a coil spring, but a rubber thread 61 is used in the figure. As far as the present inventors have experimented, it is preferable that the elastic bodies are arranged above and below the mover 7 because the frequency and volume of collision noise are small.

Although the present invention saw 1 has been described so far as a “grinding saw”, the present invention is not limited to this, and the present invention can be applied to other ordinary saws. In that case, the reciprocating motion of the saw can be in the horizontal direction, the oblique direction, or the vertical direction with the saw blade up, in addition to the vertical direction with the saw blade disposed downward. Therefore, regardless of the reciprocating motion of the saw, in order to exert the effect of reliably discharging air from the air outlet 53 and reducing the noise and impact resulting from the collision of the moving element 7, a rubber thread In this case, as shown in FIG. 4, it can be said that the coil spring is more preferable in the sense that it is necessary to support the movable element 7 from above and below.

  FIG. 4 shows still another example of the present invention, and includes a through hole 71 penetrating vertically inside the moving element 7 and a valve 72 for closing the through hole 71. This valve 72 allows the air in the other end side space 52 to pass through to the saw blade side space 51, but blocks the movement of air from the saw blade side space 51 to the other end side space 52. Check valve). Therefore, when the moving element 7 is lifted and the saw blade side space 51 is expanded, there is air in the other end side space 52 through the valve 72, and the amount of air that must be sucked from the air outlet 53 is reduced. become.

Furthermore, a nozzle valve 55 for blocking the outside air inflow may be disposed in the vicinity of the end of the air outlet 53 as shown in the drawing. In this case, when the mover 7 is lowered and the saw blade side space 51 is contracted, the air is discharged from the air ejection port 53. However, when the mover 7 is lifted and the saw blade side space 51 is expanded, the air in the mover 7 is transparent. Air is introduced only from the hole 71 portion. Accordingly, the amount of the ground powder entering the hollow portion 5 is drastically reduced, and it is expected that the risk of troubles derived from the ground powder such as clogging of the air ejection port 53 and the sliding operation of the moving element 7 can be expected.
However, the presence of the valve 72 provided on the moving element 7 or the nozzle valve 55 provided on the air outlet 53 is not essential to the present invention. The structure without the valve structure has the advantage of being simple and easy to reduce costs.

DESCRIPTION OF SYMBOLS 1 Saw which concerns on this invention 2 Saw blade 3 Saw handle 4 Bolt 5 Hollow part 51 Saw blade side space 52 Other end side space 53 Air ejection port 54 Air through-hole 55 Nozzle valve 6 Coil spring 61 Rubber thread 7 Mover 71 Through-hole 72 Valve W Wood to be processed H Hole

Claims (1)

A cylindrical hollow part is formed inside the saw handle, and a piston-like moving element is built in the hollow part, and an air ejection port whose tip is directed in the direction of the saw blade is formed from the end of the hollow part on the saw blade side. The saw has an air passage hole formed at the opposite end of the hollow portion or in the vicinity thereof, and the moving element is supported by an elastic body having one end fixed on the saw handle side. A saw characterized by being a thing.

Images