JPH033364Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention is mainly used when cutting out openings for installing pipes, cords, etc. in building materials that have already been pasted to form the walls and floors of buildings. Now, regarding a convenient small saw.

For example, when it becomes necessary to cut out an opening for inserting a synthetic resin pipe into a plywood wainscot board that has already been pasted, conventionally it is necessary to cut out an opening for inserting a synthetic resin pipe into it. Generally, a drag saw A is used, but even if an attempt is made to cut out an opening large enough to insert the pipe through the pulling operation of the saw A, the surface of the wainscot board M is smooth; On the other hand, unless the imaginary line (X-X) connecting the cutting edge of the sawtooth b is kept almost parallel to the surface of the wainscoting board M as a whole as shown in Fig. 8, the cutting edge will bite into the wainscoting board M. Therefore, it is impossible to efficiently cut out an opening of a desired size in the wainscot board M at once using only the saw a.

Therefore, as shown in Fig. 9, a small drilled hole P is drilled in advance in the waist plate M using an drill, and then the sawtooth b of the saw a is inserted into the hole from its sharp tip and pulled. The actual situation is that the opening is cut out to the desired size by manipulation.

However, since the opening is still small at the initial stage of notching, it is difficult to pull and operate the sawtooth b smoothly, and the sawtooth b must be moved in small increments. As a result, the cutting edge of the sawtooth b may accidentally come off from the drilled hole P, or when reinserted, the cutting edge may be located on a different cutting line, making it difficult to accurately and efficiently cut an opening of the desired size. Cannot work with cutouts. Since the tip of the sawtooth b also tends to swing, the sawtooth b may even be damaged due to forced contact with the drilled hole P. There is a concern that the cosmetic effect of the existing building will be hindered in the future by the above-mentioned work.

The main purpose of the present invention is to solve such problems, and its specific configuration will be explained in detail based on the illustrated embodiment. is its handle,
It is made of wood or synthetic resin and has a curved shape that is easy to hold. B is a saw blade for pulling, which is made of hardened band-like ribbon steel, and its base end is inserted and set into the split groove 11 provided at the tip of the grip handle A. , is attached and fixed with a plurality of screws, rivets 12, etc.

The pulling saw blade B has a sharply tapered shape and extends from the grip handle A, and the abdomen of one of its thick sides has a cutting edge 1 with a sorting tip.
3 is carved completely up to the tip of the saw blade B. 14 is a smooth arc-shaped notch provided on the back of the other board, which forms the other plate's thickness surface, so that when the intersection angle θ between the abdomen and the back is seen from the side, the tip of the saw blade B Sharpened to a significantly smaller acute angle. It is designed so that it can be easily inserted into the hole of the target object, which will be described later, and can be smoothly routed and used.

When the above-mentioned grip handle A is viewed from the side, it gradually becomes wider as it goes toward the base end, and the groove 15 that is obvious from FIGS. 3 to 5 is also cut out at the base end. ing. C is a circular saw blade inserted and set into the groove 15, and has a cutting edge 16 on its circumferential surface. In other words, the circular saw blade C is in the form of a so-called ratchet wheel, and the cutting edge 16 is, needless to say, subjected to a chamfering process. 17
is a shaft hole opened at the center of the circular saw blade C.

Reference numeral 18 denotes a support shaft fixed so as to pass through the shaft hole 17 and cross the groove 15 of the grip handle A, and thereby the circular saw blade C is rotatably held. In that case, the cutting edge 16 of the circular saw blade C is the grip handle A.
It protrudes outward by a certain amount H from the periphery of the hole 1, so that a hole 19 of a certain depth can be cut into an object M such as a building material. or,
In the illustrated example, the support shaft 18 is a screw consisting of a male and female removable screw fastener, but it is of course possible to use a form of support shaft 18 in place of the screw.

Further, reference numeral 20 denotes a claw piece which fixes and locks the rotation of the circular saw blade C in one direction R, while freely allowing rotation in the other direction F, and is made of a hardened plate spring having a constant band width W. Its tip is projected along the tangential direction to the circumferential surface of the circular saw blade C, and is always engaged with the cutting edge 16. In other words, the circular saw blade C and the claw piece 20 form a so-called ratchet or one-way clutch mechanism. Reference numeral 21 indicates a screw for attaching and fixing the proximal end of the claw piece 20 to the grip handle A, but it goes without saying that an adhesive or other fixing device may be used in place of the screw 21. As the claw piece 20, it is also possible to use something instead of a leaf spring.

To fix the claw piece 20, as is clear from the illustration, a concave step surface 22 is cut out in a part of the periphery of the grip handle A, and the claw piece 20 is attached to the concave step surface 22 in a so-called buried state. By doing so, it is preferable to safely keep the claw piece 20 from protruding outward from the periphery of the grip handle A, and to further restrict horizontal vibration of the claw piece 20.

In addition, based on the relationship with the usage grip form of the grip handle A shown in FIG. Depending on how you grip it, on the other hand, it may be possible to hold it in the middle of the convex curved surface that forms the back, or in the middle of the groove 15.
It is also conceivable to attach and fix the claw pieces 20 to the respective notch wall positions. However, the most suitable configuration is one in which the claw piece 20 is attached to the position shown in the figure and the grip handle A can be gripped and used as shown in FIG.
This is because it is possible to effectively apply a strong cutting force to the object M by closing the lid.

In the above configuration, when using the saw of the present invention, grip the handle A with the fingertips of one hand as shown in FIG. While pressing, pull repeatedly in the direction of arrow Y in the figure, as if scraping the smooth surface. Then, since the rotation in one direction R opposite to the arrow Y is fixed and locked by the claw piece 20, the cutting edge 16 of the circular saw blade C cuts the strip hole 19 in the object M. It can be cut open.

If the pulling operation is repeated and pushed back in the direction opposite to the arrow Y, the circular saw blade C will rotate freely, so there is no need to raise the cutting edge 16 from the surface of the object M one by one. As if tracing the hole 19, the grinding operation can be performed correctly on the same line.

After completing the opening to penetrate the target object M, as shown in FIG.
Smoothly insert the saw blade B from the tip and pull it around to completely cut out an opening for inserting a pipe or cord of the desired size and shape. In that sense, grip handle A
Although it is extremely convenient to have a circular saw blade C and a pulling saw blade B at both ends of the You can safely omit it. In addition, circular saw blade C
It is also conceivable to attach the covering opening/closing cover to the base end of the grip handle A.

In any case, in the present invention, a circular saw blade C, whose cutting edge 16 slightly protrudes from the periphery of the grip handle A, is rotatably supported on one end of the grip handle A, and a circular saw blade C is also rotatably supported on the grip handle A. Attach a claw piece 20 that engages with the cutting edge 16 of the circular saw blade C and fixes and locks only the rotation of the circular saw blade C in one direction R, and with the circular saw blade C fixed and locked by the claw piece 20, Since it is configured to use sawing to cut the holes 19 into the object M, it has the effect of completely eliminating the problems of the prior art mentioned at the beginning.

In other words, the circular saw blade C is literally circular, and therefore it is possible to reliably cut out the strip holes 19 even on the smooth surface of the object M such as existing building materials. Since only the rotation of the blade C in one direction R is fixedly locked by the claw piece 20, it is possible to apply a manual sawing action similar to that of a so-called sword-shaped saw blade. Since rotation in the direction F is freely allowed, the cutting edge 16 can be pushed back in a traced manner while the cutting edge 16 remains in contact with the slot 19, and work can therefore be done extremely smoothly and efficiently. At the same time, the desired accurate and beautiful opening can be cut out. Since the necessary configuration for this purpose is extremely simple, it can be said to be a practical device that is suitable for mass production.

[Brief explanation of the drawing]

Figures 1 and 2 are an overall side view and an overall bottom view of the saw according to the present invention, Figure 3 is a partially enlarged rear view thereof, Figure 4 is a sectional view taken along the - line in Figure 3, and Figure 5 is Figures 6 and 7 are side views showing how the circular saw blade and the pulling saw blade are used, respectively, and Figures 8 and 9 are side views showing how the conventional saw is used to cut out an opening. FIG. A... Grip handle, B... Saw blade for pulling, C... Circular saw blade, M... Target, 11, 15... Division groove, 1
3, 16...Blade tip, 18...Spindle, 19...Slot hole, 20...Claw piece, 21...Screw.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A circular saw blade C, whose cutting edge 16 slightly protrudes from the periphery of the grip handle A, is rotatably supported at one end of the grip handle A, and a circular saw blade C is rotatably supported at one end of the grip handle A. Blade C
A claw piece 20 that engages with the cutting edge 16 of the circular saw blade and fixes only the rotation of the circular saw blade C in one direction R.
This saw is configured to be used for cutting a hole 19 into an object M with the circular saw blade C fixed and locked by a claw piece 20. 2 Using the claw piece 20 as a leaf spring, attach its base end to the wooden grip handle A using a fixing device such as a screw 21, and also attach the tip end to the cutting edge 16 of the circular saw blade C. A saw according to Claim 1 of the Utility Model Registration Claim, which is secured from a tangential direction. 3. The saw according to claim 1 of the Utility Model registration claim, which comprises a grip handle A and a saw blade B for pulling at the other end.