JP7570919B2 - Portable cutting machine - Google Patents

Description

This invention relates to a portable cutting machine, and in particular to a portable cutting machine with a distinctive battery pack mounting section.

This type of portable cutting machine can be broadly divided into two types depending on the type of power source they use: those that use AC power sources and those that use rechargeable battery packs. Of these, those that use AC power sources have the disadvantage that they are difficult to handle due to the power cable that is required, and they cannot be used when there is no power source nearby. Also, with the performance of lithium-ion batteries improving in recent years, the number of machines that use rechargeable battery packs as a power source is increasing.

On the other hand, portable cut-off machines that are used with a battery pack inevitably become larger in size due to the size of the battery pack, and if the battery pack is made higher voltage to bring its performance closer to that of portable cut-off machines that use AC power, the size of the battery pack will also increase. If the overall length of the machine as viewed in the cutting direction (length in the cutting direction) increases due to an increase in the size of the battery pack, problems will arise when cutting corners in work such as replacing floors, as large areas will be out of reach of the saw blade, resulting in an increase in the amount of material left uncut.

To solve these problems, for example, Patent Document 1 discloses a structure that increases the concentration of the battery, electric motor, and saw blade, thereby shortening the overall length of the machine.

JP 2010-201598 A

However, in the conventional configuration described above, the battery mounting section is provided on the top of the battery pack, and the grip is provided above that. At this time, the battery mounting section accommodates connection terminals and wiring for electrically connecting the battery pack, in other words, a space for accommodating the connection terminals and wiring is provided under the grip. In particular, if the connection terminals of the battery mounting section are arranged close to the bottom of the grip, the space for routing the wiring becomes small, which may result in poor assembly. In addition, if space for routing the wiring is secured in the accommodation space on the bottom side of the grip, the space for holding the grip between the grip and the battery mounting section will be small as a result. In other words, when the grip is held, the space around the little finger of the hand holding the grip becomes narrow, which may impair the operability of the operator. To avoid this, the grip is provided at a high position, but if the grip is made high, the grip is farther away from the center of gravity, which reduces operability, and the machine becomes larger and harder to handle.

The objective of the present invention is to provide a portable cutting machine that can ensure space around the little finger of the hand holding the grip, without having to place the grip at a high position.

The present invention has been made to solve the above problems and has the following features:

The invention described in claim 1 is a portable cutting machine that cuts a material to be cut by rotating a saw blade with a motor, and is characterized in that it comprises a battery mounting section to which a battery pack can be attached and detached by sliding it, and a grip located above the battery mounting section, and the battery mounting section comprises a pair of rails arranged above and below to guide the battery pack in a slidable manner, and a connection terminal arranged between the pair of rails to electrically connect the battery pack , and a board on which the connection terminal is mounted is arranged in the battery mounting section so as to be approximately perpendicular to the material to be cut .

A second aspect of the present invention has the same features as the first aspect, and is further characterized in that the substrate is disposed parallel to the rail.

The invention described in claim 3 is characterized in that, in addition to the features of the invention described in claim 1 or 2 above, the battery mounting section has a plurality of the connection terminals, and the plurality of connection terminals are arranged in a vertical line.

The present invention is as described above, and the battery attachment section includes a pair of rails provided above and below to guide the battery pack so that it can slide, and a connection terminal disposed between the pair of rails to electrically connect the battery pack. With this configuration, since no rails or connection terminals are provided between the grip and the battery pack, the battery attachment section does not press on the space below the grip. Therefore, it is possible to ensure space around the little finger of the hand holding the grip without making the grip taller.

FIG. 2 is a right side view of the portable cutting machine. FIG. 2 is a plan view of the portable cutting machine. FIG. 2 is a rear view of the portable cutting machine. FIG. 2 is a right side view of the portable cutting machine with the battery pack removed. FIG. 2 is a plan view of the portable cutting machine with the battery pack removed. FIG. 2 is a rear view of the portable cutting machine with the battery pack removed. FIG. 2 is a right side view of the portable cutting machine with a portion of the housing removed. FIG. 1 is a perspective view of a portable cutting machine with a portion of the housing removed. FIG. 2A is a perspective view of the portable cutting machine with the battery pack removed, and FIG. 2B is a perspective view of the battery pack. 1A is a right side view of a portable cutting machine with adjustable cutting depth, and FIG. FIG. 13 is a right side view of the portable cutting machine according to a modified example. FIG. 13 is a right side view of the portable cutting machine with the battery pack removed, according to a modified example. FIG. 1 is a right side view of a conventional portable cutting machine with a portion of the housing removed.

An embodiment of the present invention will be described with reference to the drawings. In the following description, "upper" means the upward direction of the portable cutting machine 10 when the base 30 is placed on a horizontally placed workpiece (unless otherwise specified, the cutting depth of the saw blade 13 is maximized), and "lower" means the opposite direction to "upper". In the following description, "front" means the forward direction of the portable cutting machine 10 as seen in the cutting direction D1 of the workpiece, and "rear" means the opposite direction to "front".

The portable cutting machine 10 according to this embodiment cuts materials such as wood or steel using a circular saw blade 13 that rotates around a saw blade axis (not shown), and includes a cutting machine body 11 that rotatably supports the saw blade 13, as shown in Figures 1 to 6.

The cutting machine body 11 is equipped with a motor housing 12 that houses a motor (not shown). When the motor is operated, the saw blade 13 is rotated, allowing the material to be cut. The motor is driven by a battery pack 40 that is detachably attached to a battery attachment section 20 provided at the rear of the cutting machine body 11.

A grip 16 is provided on the top of the cutting machine body 11, approximately parallel to the cutting direction D1 of the material to be cut. A trigger 17 provided on the inside of the grip 16 is pulled to rotate the motor. The front end of the grip 16 is integrally connected to the cutting machine body 11 near the motor housing 12, and the rear end of the grip 16 is integrally connected to the rear end of the cutting machine body 11. The grip 16 is inclined so that it gradually becomes lower toward the rear when viewed from the cutting direction D1 of the material to be cut when the cutting depth (described later) is at its maximum. In addition, as shown in FIG. 1 etc., the grip 16 is located above the battery mounting part 20 in a side view (in other words, the grip 16 is located on the opposite side of the base 30, described later, when viewed from the battery mounting part 20).

A base 30 is attached to the bottom of the cutting machine body 11. The base 30 is a metal plate-shaped member that contacts the material to be cut, and is formed so that the material to be cut can be cut below the base 30 by exposing the bottom of the saw blade 13 from a cutting edge 31 that is formed through the base 30.

The front end of the base 30 is supported so as to be freely rotatable by a pivot shaft 19 provided at the front of the cutting machine body 11. By rotating the base 30 around the pivot shaft 19, the amount of protrusion of the saw blade 13 from the underside of the base 30 can be adjusted. In this way, by adjusting the amount of protrusion of the saw blade 13, the cutting depth of the material being cut can be adjusted.

The cutting depth can be adjusted by operating the cutting depth adjustment lever 18. The cutting depth adjustment lever 18 is used to lock or unlock the rotation of the base 30 and the cutting machine body 11. When adjusting the cutting depth, first rotate the cutting depth adjustment lever 18 to release the fixation between the base 30 and the cutting machine body 11. In this state, rotate the base 30 around the pivot 19, and once the desired cutting depth is set, rotate the cutting depth adjustment lever 18 in the fixing direction to fix the base 30 and the cutting machine body 11.

The upper half of the saw blade 13 above the base 30 is covered by a saw cover 14 for safety. The lower part of the saw blade 13 exposed from the cutting edge 31 of the base 30 is covered by an arc-shaped lower guard 15. This lower guard 15 is attached so that it can rotate around the rotation axis of the saw blade 13.

The battery mounting section 20 is a section that detachably engages with the battery pack 40, and as shown in Figures 4, 7, 8, etc., a board 25 is disposed inside. This board 25 is provided with a connection terminal 25a for electrically connecting the battery pack 40. In other words, when the battery pack 40 is mounted on the battery mounting section 20, the battery pack 40 and the cutting machine body 11 are electrically connected via the connection terminal 25a.

As shown in Figs. 1 and 2, the battery mounting section 20 is arranged behind the battery pack 40 (opposite the cutting direction D1 of the material to be cut) when viewed in the cutting direction D1 of the material to be cut with the battery pack 40 attached. In this embodiment, as shown in Fig. 7, etc., the board 25 is arranged so as to be approximately perpendicular to the base 30 when the cutting depth is at its maximum, and the approximately perpendicular surface of the board 25 faces the rear surface of the battery pack 40. By arranging it in this way, the battery mounting section 20 serves as a rear protection section that protects the rear of the battery pack 40 attached to the battery mounting section 20. In addition, the battery mounting section 20 does not exist between the battery pack 40 and the rear end of the grip 16, so that the position of the grip 16 can be set as low as possible.

As shown in Figures 5 and 9(a), the battery mounting section 20 includes a terminal cover section 20a, a protrusion section 20b, a latch receiving section 20c, and a rail 20d.

As shown in FIG. 9(a) and other figures, the terminal cover portion 20a is a portion that covers the circuit board 25. Inside this terminal cover portion 20a, a space is formed to accommodate the wiring cord 25b connected to the rear surface (back surface) of the circuit board 25. In this embodiment, as shown in FIG. 7, the upper end of the circuit board 25 is positioned to face the rear end of the grip 16, so the wiring cord 25b is routed through the inside of the grip 16 and wired to the switch of the trigger 17 and the motor circuit board. This eliminates the need for space for wiring below the grip 16, and allows the position of the grip 16 to be set as low as possible.

In the conventional structure, as shown in FIG. 13, the battery mounting section 20 is located between the battery pack 40 and the rear end of the grip 16, and space is required for wiring below the grip 16, so the grip 16 must be positioned high. In this regard, this embodiment does not cause such problems.

As shown in FIG. 3, a display unit 26 for displaying the status of the portable cutting machine 10 or the battery pack 40 is provided on the rear surface of the terminal cover 20a, which is part of the battery mounting unit 20 serving as the rear protective unit. By providing the display unit 26 in such a position, the display unit 26 is provided in a position directly facing the user, thereby improving the visibility of the display unit 26. Specifically, the display unit 26 is easy to see even when the cutting depth is set to the maximum as shown in FIG. 3, and is also easy to see even when the cutting depth is set to a shallow depth as shown in FIG. 10.

The content displayed on the display unit 26 is not particularly limited, but as an example, it may display the remaining charge of the battery pack 40 or any errors in the portable cutting machine 10 or the battery pack 40.

The protrusion 20b is a portion that protrudes out to the side so as to continue from the terminal cover portion 20a. By providing this protrusion 20b, a wide area of the rear surface of the battery pack 40 is covered, and the latch receiving portion 20c, which will be described later, can be disposed.

As shown in FIG. 9(a), the latch receiving portion 20c is a groove with a substantially V-shaped cross section provided on the back side of the protruding portion 20b. This latch receiving portion 20c is provided to engage with the latch 43 of the battery pack 40.

The rails 20d are provided to guide the battery pack 40 so that it can slide, and are provided along the mounting direction of the battery pack 40. In this embodiment, as shown in FIG. 9(a), two rails 20d are provided on the inside of the battery mounting section 20, one above the other.

The battery pack 40 that can be attached to the battery attachment section 20 described above is box-shaped as shown in FIG. 9(b), and one surface of the case 41 that houses multiple battery cells serves as the attachment surface to the cutting machine body 11. A terminal (not shown) for supplying electricity from the battery cells to the outside is arranged on the attachment surface. This terminal is covered by a terminal cover section 45 that has a slit. When the battery pack 40 is attached to the cutting machine body 11, the connection terminal 25a on the cutting machine body 11 side fits through the slit in the terminal cover section 45, and the terminal of the battery pack 40 and the connection terminal 25a on the cutting machine body 11 side are electrically connected.

The mounting surface of the battery pack 40 is provided with a latch 43 that can be extended and retracted from the case 41. This latch 43 is spring-biased so that it protrudes from the case 41 in its natural state.

A latch operation unit 44 for operating the latch 43 is provided on the front surface of the battery pack 40 as viewed in the removal direction D2 (see FIG. 2, etc.). This latch operation unit 44 is a button used when removing the battery pack 40 from the battery attachment unit 20. In this embodiment, by pressing in this latch operation unit 44, the biasing force of the spring biasing the latch 43 in the protruding direction is released.

In addition, a guide rail portion 42 that engages with the rail 20d of the battery mounting portion 20 described above is provided on the side of the battery pack 40 as seen in the removal direction D2. This guide rail portion 42 engages with the rail 20d, allowing the battery pack 40 to slide relative to the battery mounting portion 20 and be attached and detached. At this time, as shown in FIG. 2, in a plan view, the removal direction D2 of the battery pack 40 is perpendicular to the cutting direction D1 of the workpiece. In other words, the battery mounting portion 20 allows the battery pack 40 to be slid from the side as seen in the cutting direction D1 of the workpiece.

In this way, when the battery pack 40 is slid all the way into the battery mounting section 20, the battery pack 40 and the cutting machine body 11 are electrically connected, and the latch 43 engages with the latch receiving section 20c, fixing the battery pack 40 to the battery mounting section 20. In addition, by pressing the latch operating section 44, the engagement between the latch receiving section 20c and the latch 43 is released, and the battery pack 40 can be removed from the battery mounting section 20.

When the battery pack 40 is attached to the battery attachment section 20, as shown in FIG. 2, the battery pack 40 is offset relative to the grip 16. That is, when viewed in the longitudinal direction of the grip 16, the battery pack 40 is offset to the opposite side of the saw blade 13 (saw cover 14). By offsetting the battery pack 40 in this way, the grip 16 and the saw blade 13 (saw cover 14) can be positioned close to each other, increasing the density of the machine and achieving a compact size.

As shown in Fig. 4 and Fig. 9(a), the portable cutting machine 10 according to this embodiment includes an upper cover part 22 that covers the upper part of the battery pack 40 attached to the battery mounting part 20, and a side cover part 23 that covers the side part of the battery pack 40 attached to the battery mounting part 20 on the saw blade 13 side. As shown in Fig. 2, the upper cover part 22 is provided so that the boundary surface between the battery mounting part 20 and the battery pack 40 is not exposed at least in a plan view. In addition, the side cover part 23 is a wall provided at the end when the battery pack 40 is attached, and covers almost the entire surface (e.g., preferably 80% or more) of the side surface of the battery pack 40 to prevent cutting chips from entering from the saw blade 13 side.

By providing these upper cover portion 22 and side cover portion 23, the battery pack 40 attached to the battery attachment portion 20 is covered on three sides: the top, rear, and side facing the saw blade 13, while being configured so that three sides: the bottom, front, and side facing the saw blade 13 are exposed. However, because the base 30 is provided on the bottom and the motor housing 12 is provided on the front, the only side that is actually exposed is the side facing the saw blade 13, which needs to be opened to attach and detach the battery pack 40.

As described above, the battery attachment section 20 has a connection terminal 25a for electrically connecting the battery pack 40, and is disposed behind the battery pack 40 when viewed in the cutting direction D1 of the workpiece with the battery pack 40 attached. With this configuration, the battery attachment section 20 is not provided between the grip 16 and the battery pack 40, so the battery attachment section 20 does not press on the space below the grip 16. Therefore, it is possible to secure space around the little finger of the hand holding the grip 16 without raising the grip 16.

In addition, the rear of the battery pack 40 is protected by the battery mounting section 20 (rear protection section), so the battery pack 40 can be protected even if the machine is dropped from the rear.

In addition, because the battery pack 40 can be slid from the side when viewed in the cutting direction D1 of the material to be cut, even if the overall length of the battery pack 40 increases due to a higher voltage, the battery pack 40 can be lengthened in the removal direction D2 of the battery pack 40 (a direction perpendicular to the cutting direction D1 of the material to be cut), and this does not affect the overall length (length in the cutting direction) of the portable cutting machine 10. In other words, even if the battery pack 40 becomes larger, the overall length of the portable cutting machine 10 can be kept short, and problems such as an increase in uncut portions do not occur.

In addition, an upper cover part 22 is provided to cover the upper part of the battery pack 40 attached to the battery mounting part 20. That is, in this embodiment, since the battery mounting part 20 is not provided above the battery pack 40, there is a risk of chips falling on the battery pack 40 from above, but by providing the upper cover part 22, it is possible to prevent chips from entering. In addition, since the upper cover part 22 ensures rigidity, it is possible to compensate for the lack of strength caused by the battery mounting part 20 not being provided above the battery pack 40.

The battery pack 40 is attached to the battery mounting section 20, and the side cover 23 covers the side of the battery pack 40 on the saw blade 13 side. This configuration prevents chips from entering from the side, and the side cover 23 ensures rigidity.

In addition, a display unit 26 for displaying the status of the portable cutting machine 10 or the battery pack 40 is provided on the rear surface of the battery mounting section 20 (rear protection section). With this configuration, the display unit 26 is provided in a position directly facing the operator holding the grip 16, making the display unit 26 easy to see. In particular, the display unit 26 can be easily seen even when the cutting depth is increased and the angle of the cutting machine body 11 changes.

The board 25 on which the connection terminal 25a is mounted is arranged approximately perpendicular to the cutting direction of the workpiece. With this configuration, the board 25 is arranged approximately perpendicularly, so the thickness of the board 25 does not affect the height of the machine. In other words, the board 25 does not press on the space below the grip 16, so space can be secured around the little finger of the hand holding the grip 16 without having to make the grip 16 taller.

In the above embodiment, the battery mounting section 20 is disposed at the rear of the battery pack 40, but this is not limiting, and the battery mounting section 20 may be disposed at the front of the battery pack 40 as shown in Figs. 11 and 12. In this case, the rear of the battery pack 40 may be open, or a rear protection section may be provided to protect the rear of the battery pack 40.

REFERENCE SIGNS LIST 10 Portable cutting machine 11 Cutting machine body 12 Motor housing 13 Saw blade 14 Saw cover 15 Lower guard 16 Grip 17 Trigger 18 Cutting depth adjustment lever 19 Rotating shaft 20 Battery mounting section (rear protection section)
20a Terminal cover portion 20b Protrusion portion 20c Latch receiving portion 20d Rail 22 Upper cover portion 23 Side cover portion 25 Board 25a Connection terminal 25b Wiring cord 26 Display portion 30 Base 31 Blade opening 40 Battery pack 41 Case 42 Guide rail portion 43 Latch 44 Latch operation portion 45 Terminal cover portion D1 Cutting direction of material to be cut D2 Removal direction of battery pack

Claims (3)

A portable cutting machine that cuts a workpiece by rotating a saw blade with a motor,
a motor housing that houses the motor and protrudes to the side of the saw blade;
a battery mounting portion that is formed without using a protruding portion of the motor housing and allows a battery pack to be attached and detached by sliding the battery pack;
A grip provided above the battery mounting portion;
Equipped with
the battery mounting section includes an opening formed to expose a pair of upper and lower rails for slidably guiding the battery pack and a connection terminal disposed between the pair of rails for electrically connecting the battery pack;
The opening is disposed adjacent to the motor housing,
The pair of upper and lower rails are arranged so that their forming surfaces are substantially perpendicular to the workpiece,
A substrate on which the connection terminal is mounted is disposed in the battery mounting portion so as to be substantially perpendicular to the workpiece,
The portable cutting machine, wherein the grip has a rear end connected to the battery mounting portion and extends upward from the battery mounting portion. The portable cutting machine of claim 1, characterized in that the base plate is arranged parallel to the rail. The portable cutting machine according to claim 1 or 2, characterized in that the battery mounting section has a plurality of the connection terminals, and the plurality of connection terminals are arranged vertically.

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