JP7752560B2 - Rail cutting tool - Google Patents

Description

The present invention relates to a rail cutting tool for cutting the rails of a sash bottom frame.

Conventionally, renovation sashes have been known in which a new sash frame is installed on the inner periphery of an existing sash frame attached to an opening in the frame frame to renovate the sash. When renovating such sashes, the rails on the bottom frame of the existing sash frame are cut away. Traditionally, cutting the bottom frame rails has been done using a tool like a can opener or a chisel and hammer, but cutting the entire length of a long bottom frame rail using such hand tools takes a long time, and cutting the rails themselves is difficult when they are thick.

In light of the above-mentioned circumstances, the present invention aims to provide a rail cutting tool that can cleanly cut the rails of the lower frame in a short amount of time.

In order to achieve the above object, the rail cutting tool of the invention described in claim 1 comprises a main body having a cutting blade, a gripping portion, and a positioning portion, and a guide portion attached to the main body, the gripping portion is arranged in the vertical direction, the cutting blade is arranged below the gripping portion and rotates around a vertical axis by a motor, the positioning portion is positioned lower than the cutting blade and abuts against the upper surface of the lower frame to position the cutting blade in the vertical direction, the guide portion has a rear wall positioned behind the rail of the lower frame and spaced apart from the rail in the prospective direction , the gripping portion is gripped to insert the rail into the gap between the cutting blade and the rear wall of the guide portion, and with the positioning portion abutting against the upper surface of the lower frame, the cutting blade is pushed into the rail and moved in the longitudinal direction of the rail to cut the rail.

The rail cutting tool according to the invention described in claim 1 comprises a main body having a cutting blade, a gripping portion, and a positioning portion, and a guide portion attached to the main body, the gripping portion is arranged in the vertical direction, the cutting blade is arranged below the gripping portion and rotates around a vertical axis by a motor, the positioning portion is positioned lower than the cutting blade and abuts against the upper surface of the lower frame to position the cutting blade in the vertical direction, the guide portion has a rear wall positioned behind the rail of the lower frame and spaced apart from the rail in the prospective direction , the gripping portion is held and the rail is inserted into the gap between the cutting blade and the rear wall of the guide portion, and with the positioning portion abutting against the upper surface of the lower frame, the cutting blade is pushed into the rail and moved in the longitudinal direction of the rail to cut the rail, thereby making it possible to cleanly cut the rail of the lower frame in a short time.

1 is a side view showing one embodiment of the rail cutting tool of the present invention. FIG. FIG. 1A is a perspective view of the rail cutting tool as seen from diagonally above on the outside of the room, and FIG. 1B is a perspective view of the rail cutting tool as seen from diagonally above on the inside of the room. 1A is a perspective view of the rail cutting tool as viewed from diagonally below on the outside of the room, and FIG. 1B is a perspective view of the rail cutting tool as viewed from diagonally below on the inside of the room. 10A to 10C are side views sequentially showing the steps of cutting and removing the rails of the lower frame using the rail cutting tool. 5A to 5C are side views sequentially showing the steps (continuation of FIG. 5A) of cutting and removing the rails of the lower frame using the rail cutting tool. FIG. 2 is a side view showing an example of the rail cutting tool in use. A side view showing the state when the positioning part is replaced with one of a different height for a different lower frame and the inner rail is cut.

Embodiments of the present invention will now be described with reference to the drawings. Figures 1 to 4 show one embodiment of a rail cutting tool according to the present invention. This rail cutting tool is used to cut and remove the rails 7a and 7b from the base of the bottom frame 9 of an existing sash frame attached to an opening in the frame when renovating a sash.

As shown in Figure 1, the lower frame 9 has an outer rail 7a that guides the outer shoji screen and an inner rail 7b that guides the inner shoji screen, which protrude from the upper surface 6 of the lower frame at a distance in the indoor/outdoor direction. The outer rail 7a has a protrusion 10a that forms a tapping hole on its outdoor surface in the middle part in the vertical direction. The inner rail 7b also has a protrusion 10b on its outdoor surface in the middle part in the vertical direction. The upper ends of the outer rail 7a and inner rail 7b are at approximately the same height, with the lower end of the outer rail 7a being lower. The lower frame 9 is formed in a stepped shape with the outdoor side lowered to prevent rainwater from entering, and the upper surface 6 of the lower frame is sloped so that the outdoor side is lower.

1 to 4, the rail cutting tool comprises a main body 4 and a guide part 5 attached to the main body 4. The main body 4 has a columnar grip part 2 that is long in the vertical direction, a gear part 11 connected to the lower part of the grip part 2, a cutting blade 1 attached to a vertical rotation shaft 12 provided below the gear part 11, a cover 13 that surrounds the periphery of the cutting blade 1, and a lower cover 14 and a positioning part 15 attached to the lower surface of the cover 13.
The grip part 2 is columnar and approximately 20 cm long, with curved peripheral surfaces to fit comfortably in the hand. A motor is built into the grip part 2, and the motor is rotated by a 100-volt AC power source supplied via a power cord (not shown) or by a battery housed in the grip part 2. The grip part 2 is also provided with a switch (not shown) to turn the motor on and off.
The gear portion 11 transmits the rotation of a motor built into the grip portion 2 to a rotation shaft 12 (see FIG. 2) provided at an offset position inside the interior of the grip portion 2 .
A commercially available tipped saw for cutting metal is used as the cutting blade 1. The cutting blade 1 rotates clockwise in a plan view.
The cover 13 is formed to surround the upper surface and periphery of the cutting blade 1, and as shown in Figure 1, only the portion facing the interior of the room is open, exposing the cutting blade 1. The lower edge of the portion facing the interior of the cover 13 serves as a positioning portion 3a that positions the cutting blade 1 in the height direction by abutting against the upper surface 6 of the lower frame when cutting the outer rail 7a.
The lower cover 14 is detachably attached to the underside of the cover 13 with screws. A positioning part 15 is detachably attached to the underside of the lower cover 14 with screws, and the underside of the positioning part 15 serves as a positioning part 3b that positions the cutting blade 1 in the height direction by coming into contact with the upper surface 6 of the lower frame when cutting the inner rail 7b. As shown in Figure 4, the positioning part 15 is a square bar-shaped member with a predetermined thickness, and is provided in the left-right direction along the longitudinal direction of the lower frame 9.

The guide section 5 is provided to move the main body section 4 in the longitudinal direction of the lower frame 9 using the rails 7a and 7b of the lower frame 9 as guides, and as shown in Figure 1, has a rear wall 8 disposed behind the rails 7a and 7b and an upper wall 16 that straddles the rails 7a and 7b. The lower end of the rear wall 8 is at approximately the same height as the cutting blade 1.
The guide part 5 is attached to the main body 4 via a slide part 21 so as to be slidable in a direction (indoor/outdoor direction) toward and away from the cutting blade 1. Note that Fig. 1 shows the state in which the guide part 5 has been moved to the farthest indoor side. As shown in Fig. 1, this rail cutting tool has a space 18 between the indoor side wall 17 of the main body 4 and the cutting blade 1 and the upper wall 16 and rear wall 8 of the guide part 5 that can accommodate the protrusions 10a, 10b formed in the vertical middle of the rails 7a, 7b.

Next, the procedure for using this rail cutting tool to cut the rails 7a, 7b of the lower frame 9 will be described. First, hold the gripping portion 2 of this rail cutting tool with both hands, and at the left end position of the lower frame 9 in the longitudinal direction as viewed from the outside of the room, insert the outer rail 7a into the gap between the cutting blade 1 and the rear wall 8 of the guide portion 5 so that the rear wall 8 of the guide portion 5 is aligned with the back of the outer rail 7a, as shown in Figure 5-1(a). Then, as shown in Figure 5-1(b), place the lower edge (positioning portion) 3a of the indoor portion of the cover 13 on the upper surface 6 of the lower frame. This positions the cutting blade 1 at a height near the base of the outer rail 7a while it is spaced away from the outside of the outer rail 7a.
Thereafter, the switch provided on the gripping portion 2 is turned ON to start the rotation of the cutting blade 1, and after waiting until the rotation of the cutting blade 1 stabilizes, the cutting blade 1 is pressed against the outer rail 7a to cut into the base of the outer rail 7a, as shown in Fig. 5-1(c) . If the rotation of the cutting blade 1 is started while it is in contact with the outer rail 7a, or if the cutting blade 1 contacts the outer rail 7a while the rotation of the cutting blade 1 is accelerating, there is a risk that the cutting blade 1 will bite into the outer rail 7a and the rail cutting tool will be thrown in the direction of rotation. However, by keeping the cutting blade 1 separated from the outer rail 7a until the rotation of the cutting blade 1 stabilizes as described above, and then pressing the cutting blade 1 against the outer rail 7a after the rotation of the cutting blade 1 stabilizes, the work can be performed safely without the rail cutting tool being thrown in the direction of rotation.
The rail cutting tool is then moved from left to right along the outer rail 7a as viewed from outside the room, cutting the outer rail 7a sequentially from left to right. The guide portion 5 and positioning portion 3a allow the outer rail 7a to be cut cleanly from the base in a short amount of time. When it reaches the right end, the switch is turned OFF, and the rotation of the cutting blade 1 is stopped, and then the rail cutting tool is removed. Then, by cutting off the remaining portions at both left and right ends of the outer rail 7a using a hacksaw or chisel, the entire length of the outer rail 7a can be removed from the base, as shown in Figure 5-1(d).
Next, as with the outer rail 7a, grasp the gripping portion 2 with both hands, and at the left end position of the lower frame 9 in the longitudinal direction as viewed from the outside of the room, insert the inner rail 7b into the gap between the cutting blade 1 and the rear wall 8 of the guide portion 5 so that the rear wall 8 of the guide portion 5 is placed behind the inner rail 7b, as shown in Figure 5-2(e), and place the lower surface (positioning portion) 3b of the positioning part 15 attached to the lower cover 14 on the upper surface 6 of the lower frame. This positions the cutting blade 1 at a height position near the base of the inner rail 7b, with it spaced apart from the outside of the inner rail 7b.
Next, the switch on the gripping portion 2 is turned on to start the rotation of the cutting blade 1. After waiting for the rotation of the cutting blade 1 to stabilize, the cutting blade 1 is pressed against the inner rail 7b, as shown in FIG. 5-2(f), to cut into the base of the inner rail 7b. At this time, the rear wall 8 of the guide portion 5 is pressed against the interior wall 19 of the lower frame 9, causing the guide portion 5 to slide toward the cutting blade 1. This allows the cutting blade 1 to cut into the inner rail 7b without being obstructed by the interior wall 19 near the inner rail 7b. As with the outer rail 7a, the rail cutting tool is then moved from left to right along the inner rail 7b as viewed from the outside of the room, cutting the inner rail 7b sequentially from left to right. The remaining portions at both ends are then cut using a hacksaw or chisel, and the entire length of the inner rail 7b can be removed from the base, as shown in FIG. 5-2(g).

The above-mentioned cutting work of the rails 7a and 7b can be performed from the outside of the room by an operator standing there. However, because the gripping portion 2 of the rail cutting tool is arranged vertically, the operator can also perform the work from the inside of the room while standing inside, as shown in Figure 6. Working from the inside of the room in this way is convenient because it allows cutting of the rails 7a and 7b even when work cannot be performed from the outside, such as when there is a grille 20 on the outside of the room.

Existing lower frames 9 have a variety of cross-sectional shapes, and the distance from the upper surface 6 of the lower frame to the height position of the base of the inner rail 7b also varies depending on the lower frame 9. However, as shown in Figures 7(a) and (b), by replacing the positioning part 15 on the underside of the lower cover 14 with one that matches the shape of the lower frame 9, it is possible to cut the inner rail 7b from its base.

As described above, this rail cutting tool comprises a main body 4 having a cutting blade 1, a gripping portion 2, and positioning portions 3a, 3b, and a guide portion 5 attached to the main body 4. The gripping portion 2 is arranged in the vertical direction, the cutting blade 1 is arranged below the gripping portion 2, and rotates about a vertical axis by a motor. The positioning portions 3a, 3b are located lower than the cutting blade 1 and abut against the upper surface 6 of the lower frame to position the cutting blade 1 in the vertical direction. The guide portion 5 has a rear wall 8 located behind the rails 7a, 7b of the lower frame 9. The gripping portion 2 is held and the rails 7a, 7b are inserted into the gap between the cutting blade 1 and the rear wall 8 of the guide portion 5, and with the positioning portions 3a, 3b abutting against the upper surface 6 of the lower frame, the cutting blade 1 is pushed into the rails 7a, 7b and moved in the longitudinal direction of the rails 7a, 7b to cut the rails 7a, 7b, thereby cleanly cutting the rails 7a, 7b of the lower frame 9 in a short amount of time. Since the gripping parts 2 are provided in the vertical direction, the cutting operation of the rails 7a and 7b can be performed from the inside of the room, making it easy to use.
This rail cutting tool has a space 18 between the indoor side wall 17 of the main body 4 and the cutting blade 1 and the upper wall 16 and rear wall 8 of the guide part 5 that can absorb the protrusions 10a, 10b formed in the middle of the rails 7a, 7b in the vertical direction, so that even rails 7a, 7b that have protrusions 10a, 10b in the middle of the vertical direction can be easily cut, making it easy to use.
In addition, this rail cutting tool has positioning parts 3a, 3b for the outer rail 7a and the inner rail 7b, respectively, so that the outer rail 7a and the inner rail 7b can be cut continuously without replacing or adjusting parts, making it easy to use.
Furthermore, the positioning portion 3b of this rail cutting tool is replaceable with one of different heights, so that it can flexibly accommodate different cross-sectional shapes of the lower frame 9.
Furthermore, in this rail cutting tool, the rear wall 8 of the guide section 5 can slide freely in the direction of approaching or moving away from the cutting blade 1, which prevents the rear wall 8 of the guide section 5 from getting stuck on the indoor side wall 19 of the lower frame 9 and preventing the cutting blade 1 from being pressed against the rail 7b, thereby further improving usability.

The present invention is not limited to the above-described embodiments. The guide unit may be provided with a rear wall fixed at a position a predetermined distance away from the cutting blade. The main body may have a gripping portion extending in the indoor/outdoor direction or the left/right direction, in addition to the gripping portion extending in the vertical direction. The shape and material of the cutting blade may be modified as appropriate.

REFERENCE SIGNS LIST 1 Cutting blade 2 Grip portion 3a, 3b Positioning portion 4 Main body portion 5 Guide portion 6 Upper surface of lower frame 7a, 7b Rail 8 Rear wall 9 Lower frame

Claims (1)

A rail cutting tool comprising: a main body having a cutting blade, a gripping portion, and a positioning portion; and a guide portion attached to the main body; the gripping portion is arranged in the vertical direction; the cutting blade is arranged below the gripping portion and rotates around a vertical axis by a motor; the positioning portion is positioned lower than the cutting blade and abuts against the upper surface of the lower frame to position the cutting blade in the vertical direction; the guide portion has a rear wall positioned behind the rail of the lower frame and spaced from the rail in the prospective direction ; the tool grips the gripping portion to insert the rail into the gap between the cutting blade and the rear wall of the guide portion, and with the positioning portion abutting against the upper surface of the lower frame, pushes the cutting blade into the rail and moves it in the longitudinal direction of the rail to cut the rail.