JPH10202609A - Circular saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a clamping bolt from missing by holding the clamping bolt on a transparent cover when a circular saw blade is replaced, and in addition, prevent cutting chip from splashing at the time of cutting. SOLUTION: A circular saw blade 2 is detachably clamped to a rotating shaft 9 which is rotate-driven, and held with a clamping bolt 5, and at the same time, the circular saw blade 2 is covered with a transparent cover 6 for this circular saw. In this case, an insertion hole 10 in which a wrench 15 is passed is provided at a location corresponding with the clamping bolt 5, on the transparent cover 6, and at the same time, a holding part 11 to hold the clamping bolt 5 under a state wherein the clamping bolt 5 is removed by inserting the wrench 15 in the insertion hole 10, is provided on the transparent cover 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric circular saw for cutting an object to be cut such as wood or metal by rotating a circular saw blade, and more particularly to a structure for replacing a circular saw blade. Things.

[0002]

2. Description of the Related Art As shown in FIG. 11, a conventional electric circular saw has a circular saw blade 2 attached to a rotating shaft of a circular saw main body 1 which is driven to rotate. The circular saw blade 2 cuts the object to be cut by rotating the base plate 3 on the object to be cut and moving the base plate 3 with respect to the object to be cut. The circular saw blade 2 is removably attached to the rotating shaft by screwing a tightening bolt 5 to an end surface of the rotating shaft via a holding plate 4. A portion above the base plate 3 of the circular saw blade 2 is covered with a fixed transparent cover 6, and a portion below the base plate 3 of the circular saw tooth 2 is covered with a movable lower guard 7. The lower guard 7 is configured to rotate in the directions indicated by arrows B and C in FIG. 11 around the rotation axis, and is elastically urged to rotate in the direction indicated by arrow B. In other words, when the lower guard 7 hits the object to be cut at the time of cutting, the lower guard 7 rotates so as to retreat against the elasticity of the elastic body. The transparent cover 6 has a substantially C-shaped notch 8 exposing the fastening bolt 5 and the holding plate 4.
Is provided. When replacing the circular saw blade 2 with this circular saw, insert a wrench such as a hexagon wrench from the notch 8, loosen the tightening bolt 5, remove the tightening bolt 5 from the notch 8, and remove the holding plate 4. Then, the lower guard 7 is rotated to take out the circular saw blade 2, the new circular saw blade 2 is set on the rotating shaft in the reverse of the above, the holding plate 4 and the tightening bolt 5 are set from the notch 8, and the notch 8
The tightening bolt 5 is tightened with a wrench.

[0003]

By the way, in the above conventional example, the tightening bolt 5 is loosened from the notch 8 with a wrench such as a hexagon wrench, and the tightening bolt 5 and the holding plate 4 are removed from the notch 8. Although the circular saw blade 2 is removed and removed, the tightening bolt 5 and the holding plate 4 may be lost in the middle to take out the fastening bolt 5 and the holding plate 4 from the notch 8. Further, since the notch 8 is provided in the transparent cover 6 to replace the circular saw blade 2 as described above, there is a possibility that chips may be scattered from the notch 8 during cutting. If the circular saw blade 2 is covered with the transparent cover 6 without the notch 8 in order to eliminate the scattering of the chips, the entire transparent cover 6 is removed when the circular saw blade 2 is replaced, and the circular saw blade 2 is removed in the above-described procedure. Must be replaced, circular saw blade 2
There is a problem that it becomes difficult to replace the battery.

SUMMARY OF THE INVENTION The present invention has been made in view of the above description, and when a circular saw blade is replaced, the transparent cover can hold the tightening bolt or the tightening bolt and the holding plate, and the tightening bolt or the holding plate is lost. It is an object of the present invention to provide a circular saw capable of preventing swarf and scattering of chips during cutting.

[0005]

According to a first aspect of the present invention, there is provided a circular saw, wherein a circular saw blade 2 is removably fastened to a rotating shaft 9 which is driven to rotate by a tightening bolt 5. When the circular saw blade 2 is covered with the transparent cover 6, an insertion hole 10 for passing a wrench 15 is provided at a position corresponding to the fastening bolt 5 on the transparent cover 6, and the wrench 15 is inserted through the insertion hole 10. It is characterized in that the holding portion 11 for holding the fastening bolt 5 with the fastening bolt 5 removed is provided on the transparent cover 6. The wrench 15 is inserted through the insertion hole 10 and the wrench 15 is turned to remove the tightening bolt 5 so that the tightening bolt 5 can be held in the holding portion 11 without removing the tightening bolt 5 outside. The blade 2 can be replaced and there is no risk of losing the fastening bolt 5. Further, the fastening bolts 5 can be removed only by providing the through holes 10 through which the wrench 15 passes through the transparent cover 6, and even if the circular saw blade 2 can be replaced without removing the transparent cover 6, chips are generated at the time of cutting. Spattering can be prevented.

Further, in the circular saw according to the present invention, the holding plate 4 for holding the circular saw blade 2 when the circular saw blade 2 is tightened and fixed to the rotating shaft 9 is also integrally formed with the tightening bolt 5. It is characterized by being held by the holding section 11. In this case, when the tightening bolt 5 is removed, both the tightening bolt 5 and the holding plate 4 can be held, and loss of both the tightening bolt 5 and the holding plate 4 can be prevented.

In the circular saw according to the third aspect, in the first or second aspect, the polygonal portion 12 is provided on the rotating shaft 9 and the pressing plate 4 for holding the circular saw blade 2 corresponds to the polygonal portion 12. A polygonal hole 13 is provided, and the polygonal hole 13 of the holding plate 4 is slidably fitted in the polygonal portion 12 of the rotating shaft 9 in the axial direction of the rotating shaft 9 to prevent the holding plate 4 from rotating. It is characterized by comprising. In this case, the rotation of the holding plate 4 with respect to the rotating shaft 9 is stopped, and the tightening of the tightening bolt 5 due to the locking of the main body or the like can be prevented.

According to a fourth aspect of the present invention, in the first or second aspect, the rotary shaft 9 is provided with the spline-shaped portion 14 and the holding plate 4 for holding the circular saw blade 2 corresponds to the spline-shaped portion 14. A spline hole is provided, and the spline hole of the holding plate 4 is slidably fitted in the spline-shaped portion 14 of the rotating shaft 9 in the axial direction of the rotating shaft 9 to prevent the holding plate 4 from rotating. And Also in this case, the rotation of the holding plate 4 with respect to the rotating shaft 9 is stopped, and the tightening of the tightening bolt 5 due to the locking of the main body or the like can be prevented.

According to a fifth aspect of the present invention, there is provided the circular saw according to the first or second aspect, wherein the fastening bolt is held on the holding portion by the magnet.
In this case, the fastening bolt 5
Can be reliably held.

[0010]

2 to 4 show the entire circular saw. The circular saw main body 1 has a motor 17, a battery pack mounting portion 18, a grip 19 and the like. Circular saw body 1
Has a rotating shaft 9 rotatably supported by a bearing 20 or the like.
The rotating shaft 9 is driven by a motor 17 via a speed reducer. A receiving plate 21 is mounted on the rotating shaft 9, and a female screw hole 23 is formed in the rotating shaft 9 from an end face. In the receiving plate 21, the fitting hole 24 of the circular saw blade 2 is fitted. In this state, the male screw portion 5a of the tightening bolt 5 is screwed into the female screw hole 23 via the holding plate 4. 2
The circular saw blade 2 is clamped and held so as to sandwich the circular saw blade 2 between 1 and the holding plate 4. A base plate 3 is mounted on the circular saw main body 1, a transparent cover 6 is mounted on a portion above the base plate 3 so as to cover the circular saw blade 2, and a conventional example is provided below the base plate 3. Similarly, the lower guide 7 is rotatably mounted.

At the portion of the transparent cover 6 corresponding to the tightening bolt 5, a bottomed cylindrical holding portion 11 large enough to accommodate the head 5b of the tightening bolt 5 projects outward as shown in FIG. It is provided to do. A female screw 11a is formed in the inner periphery of the holding portion 11 so that the fastening bolt 5
The male screw 5c on the outer periphery of the head 5b can be screwed. An insertion hole 10 through which an end of a wrench 15 such as a hexagon wrench can be inserted is formed in an end of the holding portion 11.
When the circular saw blade 2 is to be replaced, a wrench 15 such as a hexagon wrench is inserted through the insertion hole 10, and the end of the wrench 15 is tightened to fit a hole such as a hexagonal hole of the head 5 b of the bolt 5. Then, the tightening bolt 5 is loosened by rotating the wrench 15 to remove the tightening bolt 5, and the male screw 5 c is screwed into the female screw 11 a of the holding portion 11 to store and hold the tightening bolt 5 in the holding portion 11. 4 and the circular saw blade 2 are removed (when the circular saw blade 2 is removed, the lower guide 7 is rotated and retracted), a new circular saw blade 2 is set, and the holding plate 4 is set. The circular saw blade 2 is attached by tightening the bolt 5. At this time, even if the fastening bolt 5 is removed, the fastening bolt 5 can be held by the holding portion 11, so that the fastening bolt 5 is not lost.

FIG. 5 shows another example. In the case of this example, the holding plate 4 is integrally provided at the base of the shaft of the fastening bolt 5. In this case, the holding plate 4 may be fixed to the fastening bolt 5 integrally, or the holding plate 4 may be rotatable around the shaft of the fastening bolt 5.
In this case, since the fastening bolt 5 and the holding plate 4 are integrated, when the fastening bolt 5 is held on the holding portion 11, the holding plate 4 is also held by the holding portion 11, and not only the fastening bolt 5 but also the holding plate 4 is lost. There is no danger.

FIGS. 6 and 7 show other examples.
In the case of the above example, since the presser plate 4 was rotatable with respect to the rotating shaft 9, when the main body was locked, the presser plate 4 was rotated together with the circular saw blade 2 by inertia, and the tightening bolts 5 were further tightened. There is a possibility that the tightening bolt 5 cannot be loosened at 15, but this example prevents this. The rotary shaft 9 is provided with a polygonal column-shaped polygonal portion 12 such as a hexagonal column, and the holding plate 4 is provided with a polygonal hole 13 such as a hexagonal hole corresponding to the polygonal portion 12. The polygonal hole 13 of the holding plate 4 is slidably fitted in the axial direction of the rotating shaft 9 to the polygonal portion 12 of the holding plate 4 to prevent the holding plate 4 from rotating. With this configuration, the holding plate 4 is prevented from rotating with respect to the rotating shaft 9 as described above, and the tightening bolt 5 is not further tightened even when the main body is locked. In this example, the holding plate 4 is separate from the fastening bolt 5, but the fastening bolt 5 and the holding plate 4 may be integrated as in the example of FIG. However, when the holding plate 4 is integrated with the fastening bolt 5, the holding plate 4 needs to be rotatable with the fastening bolt 5.

FIGS. 8 and 9 show other examples.
This embodiment also prevents retightening of the tightening bolt 5 as in the examples of FIGS. The rotating shaft 9 is provided with a spline-shaped portion 14, and the holding plate 4 is provided with a spline hole corresponding to the spline-shaped portion 14.
The spline hole of the holding plate 4 is slidably fitted in the spline-shaped portion 14 of the rotating shaft 9 in the axial direction of the rotating shaft 9 to prevent the holding plate 4 from rotating. With this configuration, the holding plate 4 is prevented from rotating with respect to the rotating shaft 9 as described above, and the tightening bolt 5 is not further tightened even when the main body is locked. Also in this example, the fastening bolt 5 and the holding plate 4 may be separate or integrated as in the above example.

FIG. 10 shows another example. In the case of the above example, when the head 5b of the tightening bolt 5 is stored and held in the holder 11, the male screw 5c of the head is inserted into the female screw 11 of the holder 11.
In this example, the magnet 16 is embedded in the transparent cover 6 around the holding portion 11 without providing the male screw 5c or the female screw 11a. With this configuration, when the fastening bolt 5 is removed and the head 5b is housed in the holding portion 11, the magnet 16 is attracted and the fastening bolt 5 and the holding plate 4 are held. However, in this case, the fastening bolt 5 and the holding plate 4 need to be formed of a ferromagnetic metal that is magnetically attached to the magnet 16.

[0016]

According to the first aspect of the present invention, as described above, an insertion hole for passing a wrench is provided at a position corresponding to the fastening bolt on the transparent cover, and the wrench is inserted into the insertion hole to remove the fastening bolt. Since the holding portion for holding the tightening bolt in the transparent state is provided on the transparent cover, the wrench can be inserted through the insertion hole, and the tightening bolt can be held in the holding portion with the wrench turned to remove the tightening bolt. The circular saw blade can be replaced without taking out the tightening bolts, and there is no danger of losing the tightening bolts.Moreover, it is necessary to remove the tightening bolts only by providing an insertion hole enough to pass a wrench through the transparent cover. Even if it is possible to replace the circular saw blade without removing the transparent cover, it can prevent chips from scattering at the time of cutting. That.

Further, the invention of claim 2 of the present invention is directed to claim 1
In tightening the circular saw blade to the rotating shaft, the holding plate that presses the circular saw blade is also held together with the tightening bolt in the above-mentioned holding portion of the transparent cover, so when the tightening bolt is removed, the tightening bolt and It is possible to hold both the holding plate and prevent the loss of both the fastening bolt and the holding plate.

Further, the invention of claim 3 of the present invention provides the method of claim 1
Or a polygonal portion corresponding to the polygonal portion is provided on a holding plate for holding the circular saw blade, and a polygonal hole of the holding plate is provided on the polygonal portion of the rotating shaft. The part is slidably fitted in the axial direction of the rotating shaft to prevent rotation of the holding plate, so that the holding plate is prevented from turning with respect to the rotating shaft, and tighten the tightening bolts with the body lock etc. It can be prevented.

The invention of claim 4 of the present invention provides the method of claim 1
Alternatively, in claim 2, a spline-shaped portion is provided on the rotating shaft and a spline hole corresponding to the spline-shaped portion is provided on a holding plate for holding the circular saw blade, and a spline hole of the holding plate is provided on the spline-shaped portion of the rotating shaft. The press plate is prevented from rotating with respect to the rotary shaft by slidably fitting in the axial direction of the rotary shaft, preventing the press plate from rotating with respect to the rotary shaft, and preventing additional tightening of the tightening bolts due to the body lock etc. Things.

[0020] The invention of claim 5 of the present invention is directed to claim 1.
Alternatively, in the second aspect, since the fastening bolt is held on the holding portion by the magnet, the fastening bolt can be easily and reliably held on the holding portion by the magnet.

[Brief description of the drawings]

FIG. 1 is a partially exploded sectional view of a main part of an example of the present invention.

FIG. 2 is a side view of the entire circular saw according to the first embodiment.

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is a front view of FIG. 2;

FIG. 5 is a sectional view of a main part of another example of the embodiment.

FIG. 6 is an exploded perspective view of a main part of another example of the above.

7A and 7B show the rotation shaft of FIG. 6, wherein FIG. 7A is a partially cutaway front view and FIG. 7B is a side view.

FIG. 8 is a partially cutaway perspective view of a main part of another example of the embodiment.

9A and 9B show the rotation shaft of FIG. 8, wherein FIG. 9A is a partially cutaway front view and FIG. 9B is a side view.

FIG. 10 is a sectional view of a main part of another example of the above.

FIG. 11 is a side view of a conventional example.

[Explanation of symbols]

 2 Circular saw blade 4 Holding plate 5 Tightening bolt 6 Transparent cover 10 Insertion hole 11 Holder 12 Polygonal part 13 Polygonal hole part 14 Spline shape part 15 Wrench 16 Magnet

Claims (5)

[Claims] 1. A circular saw in which a circular saw blade is removably fastened to a rotating shaft that is driven to rotate by a fastening bolt and the circular saw blade is covered with a transparent cover, and corresponds to the fastening bolt of the transparent cover. A circular saw comprising: a transparent cover provided with an insertion hole through which a wrench is inserted at a position, and a holding portion for holding the tightening bolt with the wrench inserted through the insertion hole and the tightening bolt being removed. 2. A holding plate for holding a circular saw blade when the circular saw blade is fastened and fixed to a rotating shaft is held together with a tightening bolt on the holding portion of the transparent cover. Circular saw as described. 3. A polygonal portion is provided on the rotating shaft, and a polygonal hole corresponding to the polygonal portion is provided on a holding plate for holding the circular saw blade, and a polygonal hole of the holding plate is provided on the polygonal portion of the rotating shaft. The circular saw according to claim 1 or 2, wherein the pressing plate is slidably fitted in the axial direction of the rotating shaft to prevent rotation of the holding plate. 4. A spline-shaped portion is provided on the rotating shaft, and a spline hole corresponding to the spline-shaped portion is provided on a holding plate for holding the circular saw blade, and the spline hole of the holding plate is rotated on the spline-shaped portion of the rotating shaft. 3. The circular saw according to claim 1, wherein the holding plate is slidably fitted in the axial direction of the shaft to prevent the holding plate from rotating. 5. The circular saw according to claim 1, wherein the fastening bolt is held on the holding portion by a magnet.