EP2233237A2

EP2233237A2 - Mitre Circular Saw With Upper Table

Info

Publication number: EP2233237A2
Application number: EP10157334A
Authority: EP
Inventors: Masahiko Inai
Original assignee: Makita Corp
Current assignee: Makita Corp
Priority date: 2009-03-25
Filing date: 2010-03-23
Publication date: 2010-09-29
Also published as: EP2233237A3; JP2010221389A; CN101844249B; CN101844249A

Abstract

A mitre circular saw (1) with an upper table (36) comprises: a base (10) for placing a workpiece; a main body (30) having a saw blade (34) and vertically movable relative to the base (10); a safety cover (31A, 31B) rotatably movable for shielding or exposing the saw blade (34) by an upward and downward movements of the main body (30); a blade edge plate (14A, 14B) for defining a slit (15) where the saw blade (34) enters when the main body (30) is lowered; and an upper table (36) disposed above the main body (30) along which a workpiece is slidable. An inlet for chips (18) is formed in the upper surface of the base (10) forwardly of and partitioned from the slit (15), and chips generated by cutting the workpiece on the upper table (36) at the predetermined lowered position of the main body (30) arc guided to pass through an interior of the safety cover (31A, 31B) in the open position and to flow toward the inlet for chips (18).

Description

BACKGROUND OF THE INVENTION

1. Field of the invention

This invention relates to a mitre circular saw with an upper table, which can be used both as a mitre circular saw machine for cutting a workpiece placed on a base by lowering a main body having a saw blade and as a table saw with the use of a table provided at an upper part of the main body.

2. Description of related art

Japanese Laid-open Patent Publication No. 2005-169742 discloses a mitre circular saw with an upper table, in which a mitre circular saw mode and a table saw mode can be selectively used. In the mitre circular saw mode, a workpiece placed on a table such as a base is cut using a lower edge portion of a circular saw blade that is driven to rotate, and in the table saw mode, a workpiece placed on the upper table that is arranged above the table is cut using an upper edge portion of the circular saw blade.
This conventional mitre circular saw has a discharge nozzle for chips at a front side of a lower surface of the upper table, and chips generated in the table saw mode are discharged toward the front side of the upper table through the discharge nozzle. A dust collector may be connected to the discharge nozzle through a suction hose, so that chips can be collected by the dust collector through the suction hose.
However, in conventional mitre circular saws with an upper table such as disclosed in JP 2005-169742 A , chips are discharged from the discharge nozzle toward the front side of the upper table. This is disadvantageous because chips are scattered toward a user standing in front of the upper table during cutting of the workpiece, and the user may experience a feeling of discomfort.
Further, in the case where the suction hose is connected to the discharge nozzle, the suction hose may become an obstacle for the user standing in front of the upper table during cutting of the workpiece. This disadvantageously leads to a difficulty in a smooth cutting operation for the workpiece, and thus results in a hard-to-operate mitre circular saw.
In view of the above, it is an object of the present invention to provide a mitre circular saw with an upper table, which can improve the operability while preventing the user from experiencing a feeling of discomfort.

SUMMARY OF THE INVENTION

In accordance with the present invention as embodied and described herein as a first embodiment, a mitre circular saw with an upper table comprises: a base on which a workpiece is placed; a main body disposed above the base and configured to be movable upward and downward with respect to the base; a saw blade provided on the main body and configured to be driven to rotate; a safety cover provided on the main body and configured to be rotatably moved by an upward and downward movements of the main body, between a covering position at which the safety cover is positioned at a lower side of the main body to shield the saw blade and an open position at which the safety cover is positioned at a front side of the main body to expose a lower edge of the saw blade; a blade edge plate provided on an upper surface of the base and having a slit where the saw blade is permitted to enter when the main body is lowered; and an upper table disposed above the main body and configured such that an upper edge of the saw blade penetrates the upper table at a predetermined lowered position of the main body and a workpiece is slidable on an upper surface of the upper table in a front-back direction, characterized in that an inlet for chips is formed in the upper surface of the base forwardly of and partitioned from the slit, and that chips generated by cutting the workpiece on the upper table at the predetermined lowered position of the main body are guided to pass through an interior of the safety cover in the open position and to flow toward the inlet for chips.
With this configuration of the mitre circular saw, chips generated by cutting the workpiece on the upper table are guided to pass through the interior of the safety cover in the open position and to flow toward the inlet for chips. Therefore, chips are not scattered toward the user, so that the user does not feel any discomfort.
Further, it is not necessary to arrange a suction hose for collecting chips at the front face side of the upper table. Therefore, the suction hose does not become an obstacle for the user during the cutting operation of a workpiece, leading to improved operability of the mitre circular saw.
Preferably, in a second embodiment, the mitre circular saw according to the first embodiment may be characterized in that a width dimension of the inlet for chips is not smaller than that of the slit.
With this configuration of the mitre circular saw, chips can readily flow into the inlet for chips, since the width dimension of the inlet for chips is not smaller than that of the slit.
Preferably, in a third embodiment, the mitre circular saw according to the first embodiment or the second embodiment may be characterized in that a discharge passage for chips is formed in the base, by which chips generated by cutting the workpiece on the base are guided toward a rear side of the base, and that the inlet for chips is in communication with the discharge passage for chips.
With this configuration of the mitre circular saw, chips flowing into the inlet for chips can be guided along the discharge passage for chips, since the inlet for chips is in communication with the discharge passage for chips. Therefore, it is not necessary to provide a passage for discharging chips, other than this discharge passage for chips.
Preferably, in a fourth embodiment, the mitre circular saw according to any one of the first to third embodiments may be characterized in that the blade edge plate comprises a right blade edge plate and a left blade edge plate which are slidable in a right-left direction relative to the base, and that the slit is formed between the right blade edge plate and the left blade edge plate when one of or both of the right and left blade edge plates are slid in the right-left direction.
Preferably, in a fifth embodiment, the mitre circular saw according to the fourth embodiment may be characterized in that a partition member for partitioning the slit and the inlet for chips is fixed to one of the right and left blade edge plates, the partition member being configured to bridge across the slit and reach to the other one of the left and right blade edge plates.
With these configurations according to the fourth and fifth embodiments, the partition member is fixed to one of the right and left blade edge plates, and the partition member bridges across the slit at the front end of the slit. Therefore, even in the case where the width dimension of the slit is adjusted by sliding the right and left blade edge plates in the right-left direction relative to the base, the partition member is slidable in the right-left direction while remaining a bridged state at the front end of the slit. This makes it possible to always define the inlet for chips at a front side of the slit separately from the slit.
Further, as described above, since the inlet for chips can be defined even after the width dimension of the slit is adjusted, it is not necessary to perform processing on the base for the purpose of defining the inlet for chips in accordance with the adjusted width dimension of the slit.
This is advantageous because the inlet for chips can be defined in accordance with the width dimension of the slit without substantial increase of the cost.
Preferably, in a sixth embodiment, the mitre circular saw according to any one of the first to fifth embodiments may be characterized in that a front end of the inlet for chips substantially aligns perpendicularly with or is positioned forwardly of a front end of a lower end opening of the safety cover that is positioned in a proximity of the upper surface of the base at its open position.
With this configuration of the mitre circular saw, since the front end of the inlet for chips is set to substantially aligns perpendicularly with or to be positioned forwardly of the front end of the lower end opening of the safety cover that is positioned in the proximity of the upper surface of the base, the inlet for chips can be arranged in a position to which chips flowing inside the safety cover are guided.
Therefore, it is possible to effectively guide the chips toward the inlet for chips.

BRIEF DESCRIPTION OF THE DRAWINGS

The above aspect, other advantages and further features of the present invention will become more apparent by describing in detail illustrative, non-limiting embodiments thereof with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a mitre circular saw with an upper table according to one embodiment of the present invention, illustrating a state before a circular saw main body is lowered;
FIG. 2 is a perspective view of the mitre circular saw, illustrating a state in which the circular saw main body has been lowered;
FIG. 3 is a side view of the mitre circular saw, illustrating a state in which the circular saw main body has been lowered;
FIG. 4 is a plan view showing the structure around a turntable of the mitre circular saw; and
FIG. 5 is a sectional view showing main parts of the mitre circular saw with the circular saw main body positioned in a lowered position.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIGS. 1 to 5, a preferred embodiment of the present invention will be described in detail. A mitre circular saw with an upper table 1 as shown in the figures comprises a base 10, a main body support portion 20, and a circular saw main body 30.
The base 10 comprises a turntable 11 and a fence 12. A workpiece such as wood is placed on an upper surface of the turntable 11. A handle 11A is provided at a front side of the turntable 11. When a user holds and operates the handle 11A, the turntable 11 moves horizontally and comes to rest at predetermined horizontal rotation angles. The fence 12 is positioned at an upper part of the base 10. The fence 12, against which wood (workpiece) is brought into abutment, is used for positioning the wood.
As seen in FIG. 4, a left blade edge plate 14A and a right blade edge plate 14B are mounted on an upper surface of the turntable 11 while being spaced apart from each other. A slit 15 is formed between the left blade edge plate 14A and the right blade edge plate 14B. A long hole 16A, 16B is formed in each of the blade edge plates 14A, 14B. A screw is loosely fitted into the long hole 16A, 16B and then threadedly engaged with a corresponding screw hole formed in the turntable 11. Thereby, the left blade edge plate 14A and the right blade edge plate 14B are fixed to turntable 11. When one of or both of left blade edge plate 14A and the right blade edge plate 14B are slid along the longitudinal direction (right-left direction) of the long holes 16A, 16B relative to the turntable 11, positions to which the left and right blade edge plates 14A, 14B are fixed can be adjusted.
Since the slit 15 is formed between the left blade edge plate 14A and the right blade edge plate 14B, the width dimension W1 of the slit 15 can be adjusted by changing the positions to which the blade edge plates 14A, 14B are fixed on the turntable 11. As will be described later, a lower edge portion of the saw blade 34 enters the slit 15.
As best seen in FIG. 4, a partition member 17 is provided at a front end of the slit 15. The partition member 17 is fixed to a reverse surface of the left blade edge plate 14A, and bridges between the left blade edge plate 14A and the right blade edge plate 14B. Therefore, even if the width dimension W1 of the slit 15 is changed by sliding the respective blade edge plates 14A, 14B along the longitudinal direction of the long holes 16A, 16B, the partition member 17 moves in the same direction as the left blade edge plate 14A and the right blade edge plate 14B slide while remaining a bridged state across the slit 15.
An inlet for chips 18 is defined in a space surrounded by the partition member 17, the left and right blade edge plates 14A, 14B, and the front edge of the upper surface of the turntable 11. As will be described later, chips generated by cutting wood that is placed on the upper table 36 fall into the inlet for chips 18. Because of the partition member 17 at the front end of the slit 15, the slit 15 and the inlet for chips 18 positioned forwardly of the slit 15 can be partitioned. According to this embodiment, the width dimension W2 of the inlet for chips 18 is greater than the width dimension W1 of the slit 15.
Further, as best seen in FIG. 5, a discharge passage for chips R is formed inside the turntable 11. An inlet of the discharge passage for chips R opens toward the upper surface of the turntable 11 through the slit 15, and an outlet of the discharge passage R opens toward the rear side of the base 10 through a discharge tube 19. The discharge passage for chips R extends from the slit 15 downwardly along an outer periphery of the saw blade 34 and then obliquely upwardly to the discharge tube 19 at the rear side of the base 10. The discharge tube 19 is connected to a dust bag or through a suction hose to a dust collector. Chips generated by cutting wood that is placed on the upper surface of the turntable 11 flow into the discharge passage for chips R from the slit 15. The chips are guided along the discharge passage R toward the discharge tube 19. As best seen in FIG. 5, the discharge passage for chips R is in communication with the inlet for chips 18 within the turntable 11.
A main body support portion 20 comprises a support member 21 and an upward-downward movement supporting pin 22. One end of the support member 21 is pivotally supported on the turntable 11 by a tilt pin 23 (see FIG. 5). The support member 21 is tiltable by means of the tilt pin 23 and extends above the turntable 11. Provided in the proximity of the tilt pin 23 is a lock lever 24. The support member 21 can be held stationary by the lock lever 24 while being tilted by a predetermined angle. A circular saw main body 30 to be described later is mounted to the other end of the support member 21 through the upward-downward movement supporting pin 22 in a manner pivotable in the upward-downward direction, and the circular saw main body 30 is urged by a compression spring (not shown) to an upper dead point as shown in FIG. 1.
The circular saw main body 30 includes safety covers 31A, 31B, a blade cover 32, an electric motor 33, a saw blade 34, a handle 35, an upper table 36, and an upper cover 37. Reference characters 39 and 38 in the drawings indicate an actuation switch for the electric motor 33 and a stop switch for the electric motor 33, respectively. As seen in FIG. 1, in a state before the circular saw main body 30 is lowered, the blade cover 32 shields a side portion of the saw blade 34, the safety cover 31A is positioned under the circular saw main body 30 to shield a lower edge portion of the saw blade 34, and the safety cover 31B shields a side portion of the saw blade 34. It is to be noted that the circular saw main body 30 is an example of a main body according to the present invention and the illustrated position before the circular saw main body 30 is lowered indicates an example of a covering position according to the present invention.
Meanwhile, when the user lowers the circular saw main body 30 using the handle 35, because of a synchronization mechanism with a linkage, the safety covers 31A, 31B are rotated upward with a rotary support pin 31C as a rotation center. Therefore, as seen in FIGS. 2, 3 and 5, the safety covers 31A, 31B are positioned at the front side of the circular saw main body 30 and are all substantially superposed one another, and the lower edge portion of the saw blade 34 is exposed from the safety covers 31A, 31B. In this position, as best seen in FIGS. 2 and 5, the lower edge portion of the saw blade 34 enters the slit 15. The position as shown in FIGS. 2, 3 and 5, in which the circular saw main body 30 has been lowered, indicates an example of an open position according to the present invention.
Furthermore, as will be understood from FIG. 5, when the circular saw main body 30 has been fully lowered by the user, the lower end opening of the safety cover 31A is positioned in the close vicinity of the upper surface of the turntable 11. And the perpendicular line passing through the front end 18A of the inlet for chips 18 is substantially aligned with the perpendicular line passing through the front end 31D of the lower end opening of the safety cover 31A. Thereby, when looking down from above the mitre circular saw with the upper table 1, the front end 18A of the inlet for chips 18 is set to substantially overlap with the front end 31D of the lower end opening of the safety cover 31A.
The upper table 36 is disposed above the circular saw main body 30. As seen in FIGS. 2 and 5, a slit 36B is formed in the upper table 36, penetrating the upper table 36. When the circular saw main body 30 is lowered to the position such as shown in FIGS. 2 and 3, the upper end portion of the saw blade 34 protrudes from the upper surface 36A of the upper table 36 through the slit 36B (see FIG. 5). It is to be noted that the position in which the circular saw main body 30 has been lowered as seen in FIGS. 2 and 3 indicates a predetermined lowered position according to the present invention. The circular saw main body 30 can be held stationary in the lowered position (where the circular saw main body 30 has been lowered) by a locking mechanism (not shown).
As best seen in FIG. 5, the upper end portion of the saw blade 34 which protrudes from the upper surface 36A is shielded by the upper cover 37. The upper cover 37 is pivotally mounted to the support member 37B by a rotary support pin 37A. FIG. 5 illustrates a state in which the upper cover 37 is brought into contact with the upper surface 36A. As seen in the figure, the support member 37B penetrates the upper surface 36A and is fixed to the circular saw main body 30 by bolts 37C. As will be described later, wood is placed on the upper surface 36A and cut by the upper edge portion of the saw blade 34.
Next, operation of the mitre circular saw with the upper table 1 will be described. The mitre circular saw with the upper table 1 has a mitre circular saw mode and a table saw mode, which can be used in a selective manner. In the mitre circular saw mode, the actuation switch 39 is turned on and the circular saw main body 30 is lowered by the user, so that the wood placed on the upper surface of the turntable 11 can be cut by the lower edge portion of the saw blade 34 that is driven to rotate by the electric motor 33 in a direction indicated by the solid arrow of FIGS. 3 and 5. Chips discharged by cutting the wood are collected by means of the dust bag or the dust collector, passing through the discharge tube 19 (or passing through the discharge passage for chips R and the discharge tube 19, in the case where the circular saw main body 30 is positioned in the vicinity of the lowered position).
Meanwhile, in the table saw mode, chips generated by cutting wood that is placed on the upper surface 36A of the upper table 36 are collected by the following manner. The user places wood on the upper surface 36A while the circular saw main body 30 is fixed to the lowered position as described above, and then the user holds and slides the wood along the upper surface 36A from the front side of the upper surface 36A toward the upper cover 37 positioned at the rear side of the upper surface 36A. When the wood is slid on the upper cover 37 in this direction, the wood causes the upper cover 37 to be lifted up with the rotary support pin 37A as a rotation center. Thereby, the upper edge portion of the saw blade 34 is exposed from the upper cover 37. The wood slid on the upper surface 36A is cut by the upper edge portion of the saw blade 34 that is driven to rotate by the electric motor 33.
Chips generated by cutting the wood using the upper edge portion of the saw blade 34 (hereinafter referred to as wood chips) flow into the slit 36B that is formed in the upper table 36 in a penetrating manner, and pass through the inside of the blade cover 32 and the safety covers 31A, 31B in a direction indicated by the two-dot chain line of FIG. 5, and thereafter the wood chips are scattered downward from the safety cover 31A. As described above, since the front end 31D of the lower end opening is set to substantially overlap with the front end 18A of the inlet for chips 18, the wood chips scattered downward from the safety cover 31A are guided to the inlet for chips 18. According to this embodiment, since the width dimension W2 of the inlet for chips 18 is greater than the width dimension W1 of the slit 15, the opening width of the inlet for chips 18 becomes greater at the upper surface of the turntable 11 than the opening width of the slit 15.
As described above, since the inlet for chips 18 is in communication with the discharge passage for chips R within the turntable 11, wood chips flow into the base 10 from the inlet for chips 18, and are guided through the discharge passage for chips R toward the discharge tube 19 at the rear side of the base 10. Thereafter, the wood chips are collected from the discharge tube 19 to the dust collector and the like through the suction hose.

Advantageous effects of the preferred embodiment

According to the mitre circular saw with the upper table 1 in this preferred embodiment, in the table saw mode, the lower end opening of the safety cover 31A is positioned in the vicinity of the upper surface of the turntable 11. In this position, wood chips are guided downwardly of the safety cover 31A and then flow into the inlet for chips 18. Therefore, the wood chips can be collectively guided to the inlet for chips 18. Accordingly, it is possible to prevent wood chips from being guided forwardly of the mitre circular saw 1 and scattered toward the user, so that the user does not feel any discomfort.
Further, it is not necessary to arrange a suction hose for collecting wood chips at the front side of the upper table 36. Therefore, the suction hose does not become an obstacle for the user during the cutting operation of wood, leading to improved operability of the mitre circular saw with the upper table 1.
As described above, the opening width of the inlet for chips 18 is greater at the upper surface of the turntable 11 than the opening width of the slit 15. Therefore, in the table saw mode, wood chips are more likely to flow into the inlet for chips 18 than into the slit 15.
Further, since the inlet for chips 18 is in communication with the discharge passage for chips R within the turntable 11, wood chips flowing into the inlet for chips 18 can pass through the discharge passage for chips R. Therefore, it is not necessary to provide a passage for discharging wood chips, other than the discharge passage for chips R.
In the above preferred embodiment, the partition member 17 is fixed to the reverse surface of the left blade edge plate 14A while bridging the slit 15 at the front end of the slit 15. Therefore, even in the case where the width dimension W1 of the slit 15 is adjusted by sliding each of the right and left blade edge plates 14A, 14B in the longitudinal direction of the long holes 16A, 16B relative to the turntable 11, the partition member 17 is slidable in the same direction as the right and left blade edge plates 14A, 14B slide along while bridging across the slit 15. This makes it possible to always define the inlet for chips 18 at the front side of the slit 15 separately from the slit 15.
Further, as described above, since the inlet for chips 18 can be formed even after the width dimension W1 of the slit 15 is changed for adjustment, it is not necessary to perform processing on the turntable 11 or the base 10 for the purpose of defining the inlet for chips 18 in accordance with the adjusted width dimension W1 of the slit 15.
This is advantageous because the inlet for chips 18 can be formed in accordance with the width dimension W1 of the slit 15 without substantial increase of the cost.
Furthermore, in the table saw mode, since the front end 18A of the inlet for chips 18 is set to substantially overlap with the front end 31D of the lower end opening of the safety cover 31A, the inlet for chips 18 can be arranged in a position to which wood chips scattered downward from the safety cover 31A are guided.
Therefore, it is possible to effectively guide the wood chips toward the inlet for chips 18.
Although the present invention has been described in detail with reference to the above preferred embodiment, the present invention is not limited to the above specific embodiment and various changes and modifications may be made without departing from the scope of the appended claims. For example, in the above preferred embodiment, the partition member 17 is fixed to the reverse surface of the left blade edge plate 14A so as to bridge between the left blade edge plate 14A and the right blade edge plate 14B. However, as an alternative, the partition member 17 may be fixed to the reverse surface of the right blade edge plate 14B.
In the above preferred embodiment, the front end 18A of the inlet for chips 18 is set to be substantially aligns perpendicularly with the front end 31D of the lower end opening of the safety cover 31A. However, as an alternative, the front end 18A may be positioned forwardly of the front end 31D, when looking down the mitre circular saw with the upper table 1 from above. Therefore, as with the above preferred embodiment, the inlet for chips 18 can be arranged in a position to which wood chips scattered downward from the safety cover 31A are guided.
Further, in the above preferred embodiment, the safety cover is divided into two parts. However, as an alternative, the safety covers 31A, 31B may be formed as an integral cover.
It is explicitly stated that all features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original disclosure as well as for the purpose of restricting the claimed invention independent of the composition of the features in the embodiments and/or the claims. It is explicitly stated that all value ranges or indications of groups of entities disclose every possible intermediate value or intermediate entity for the purpose of original disclosure as well as for the purpose of restricting the claimed invention, in particular as limits of value ranges.

Claims

A mitre circular saw (1) with an upper table comprising
a base (10) on which a workpiece can be placed,
a main body (30) disposed above the base (10) and configured to be movable upward and downward with respect to the base (10),
a saw blade (34) provided on the main body (30) and configured to be driven to rotate,
a safety cover (31A, 31B) provided on the main body (30) and configured to be rotatably moved by upward and downward movements of the main body (30), between a covering position at which the safety cover (31A, 31B) is positioned at a lower side of the main body (30) to shield the saw blade (34) and an open position at which the safety cover (31A, 31B) is positioned at a front side of the main body (30) to expose a lower edge of the saw blade (34),
a blade edge plate (14A, 14B) provided on an upper surface of the base (10) and having a slit (15) where the saw blade (34) is permitted to enter when the main body (30) is lowered, and
an upper table (36) disposed above the main body (30) and configured such that an upper edge of the saw blade (34) penetrates the upper table (36) at a predetermined lowered position of the main body (30) and a workpiece is slidable on an upper surface of the upper table (36) in a front-back direction,
characterized in that an inlet for chips (18) is formed in the upper surface of the base (10) forwardly of and partitioned from the slit (15), and that chips generated by cutting the workpiece on the upper table (36) at the predetermined lowered position of the main body (30) are guided to pass through an interior of the safety cover (31A, 31B) in the open position and to flow toward the inlet for chips (18).
The mitre circular saw (1) according to claim 1, wherein a width dimension of the inlet for chips (18) is not smaller than that of the slit (15).
The mitre circular saw (1) according to claim 1 or 2, wherein a discharge passage for chips (R) is formed in the base (10), by which chips generated by cutting the workpiece on the base (10) are guided toward a rear side of the base (10), and wherein the inlet for chips (18) is in communication with the discharge passage for chips (R).
The mitre circular saw (1) according to any one of claims 1 to 3, wherein the blade edge plate (14A, 14B) comprises a right blade edge plate (14B) and a left blade edge plate (14A) which are slidable in a right-left direction relative to the base (10), and wherein the slit (15) is formed between the right blade edge plate (14B) and the left blade edge plate (14A) when one of or both of the right and left blade edge plates (14B, 14A) are slid in the right-left direction.
The mitre circular saw (1) according to claim 4, wherein a partition member (17) for partitioning the slit (15) and the inlet for chips (18) is fixed to one of the right and left blade edge plates (14B, 14A), the partition member (17) being configured to bridge across the slit (15) and reach to the other one of the right and left blade edge plates (14B, 14A).
The mitre circular saw (1) according to any one of claims 1 to 5, wherein a front end of the inlet for chips (18) substantially aligns perpendicularly with or is positioned forwardly of a front end of a lower end opening of the safety cover (31A, 31B) that is positioned in a proximity of the upper surface of the base (10) at its open position.
The mitre circular saw (1) according to claim 3, wherein the discharge passage for chips (R) extends from the slit (15) downwardly along a outer periphery of the saw blade (34) and then obliquely upwardly to the rear side of the base (10).
The mitre circular saw (1) according to claim 3 or 7, wherein an outlet of the discharge passage for chips (R) opens rearwardly of the base (10) through a discharge tube (19).
The mitre circular saw (1) according to claim 8, wherein a dust bag or a dust collector is connected to the discharge tube (19).
The mitre circular saw (1) according to claim 5, wherein the partition member (17) is fixed to a reverse surface of one of the right and left blade edge plates (14B, 14A).
The mitre circular saw (1) according to claim 5 or 10, wherein a long hole (16A, 16B) extending in the right-left direction is formed in the right blade edge plate (14B) and the left blade edge plate (14A), respectively, and a screw is loosely fitted into the long hole (16A, 16B) and threadedly engaged with the base (10).
The mitre circular saw (1) according to any one of claims 1 to 11, wherein a fence (12) is provided on the upper surface of the base (10) so that the workpiece is brought into abutment against the fence (12) for positioning thereof.
The mitre circular saw (1) according to any one of claims claim 1 to 12, wherein an upper cover for shielding the upper edge of the saw blade (34) penetrating the upper table (36) is rotatably mounted to the main body (30) through a rotary support pin (31C) and lies on the upper table (36), and wherein by sliding the workpiece on the upper table (36), the upper cover (37) is lifted up with the rotary support pin (31 C) as a rotation center, so that the upper edge of the saw blade (34) is exposed from the upper cover (37).