阅读说明：本技术 电池式电动工具 (Battery type electric tool ) 是由 藤森崇太 横山聪哉 井户田淳 稻垣史雄 于 2020-03-12 设计创作，主要内容包括：提供能够抑制外部的灰尘等被吸引到工具主体内的电池式电动工具,该电池式电动工具(1)具有：壳体(24),其具有吸气口(46)及排气口(48)；马达(26),其安装于该壳体内；工具驱动部(38),其被马达(26)驱动而旋转；冷却风扇(30),其与马达(26)一起旋转；以及电池装配部(32),其设置于壳体(24)的周壁(24-3),且将电池(14)以能够装卸的方式装配于周壁(24-3)的外侧面上。电池装配部(32)在装配的电池(14)与周壁(24-3)的设置有吸气口(46)的部分之间划定出具有朝向上方的向上开口(74-1)的空气取入空间(74)。(Provided is a battery-powered power tool capable of suppressing external dust and the like from being attracted into a tool body, the battery-powered power tool (1) comprising: a casing (24) having an air inlet (46) and an air outlet (48); a motor (26) mounted within the housing; a tool driving unit (38) that is driven by the motor (26) to rotate; a cooling fan (30) that rotates together with the motor (26); and a battery mounting part (32) which is provided on the peripheral wall (24-3) of the case (24) and detachably mounts the battery (14) on the outer side surface of the peripheral wall (24-3). The battery mounting section (32) defines an air intake space (74) having an upward opening (74-1) facing upward between the mounted battery (14) and the portion of the peripheral wall (24-3) where the air intake opening (46) is provided.)

1. A battery-powered electric tool in which, in a state in which,

the battery-powered electric tool includes:

a housing having a bottom wall facing a workpiece during machining operation, a top wall located above the bottom wall, and a peripheral wall between the bottom wall and the top wall, the housing having an air inlet for taking air from outside the housing into the housing, and an air outlet for discharging air from the housing to outside the housing, and at least the air inlet being provided in the peripheral wall;

a motor mounted in the housing;

a tool driving unit mounted on the housing and driven by the motor;

a cooling fan which is installed in the housing and rotates with the rotation of the motor, and which sucks air outside the housing into the housing through the air inlet and discharges the air outside the housing through the air outlet to cool the housing; and

and a battery mounting portion that is provided on the peripheral wall of the casing and detachably mounts a battery that supplies electric power to the motor on an outer surface of the peripheral wall, wherein the battery mounting portion defines an air intake space that has an upward opening between the battery and a portion of the peripheral wall where the air intake port is provided when the battery is mounted, and draws air into the casing through the upward opening, the air intake space, and the air intake port when the cooling fan rotates.

2. The battery-powered power tool according to claim 1,

the battery mounting portion has a bottom plate extending from the peripheral wall of the case to at least partially cover a bottom surface of the mounted battery from below.

3. The battery-powered power tool according to claim 1 or 2, wherein,

the battery mounting portion has a battery facing portion that contacts or approaches the mounted battery at a position below the air intake port to suppress air from flowing from below into the air intake space.

4. The battery-powered power tool according to any one of claims 1 to 3,

the air intake space has a side opening that opens in at least either of the left and right directions and allows air to flow into the air intake space.

5. The battery-powered power tool according to any one of claims 1 to 4,

when the battery is mounted, an extended lower space continuous with the air intake space is defined between the peripheral wall and the battery at a position continuing downward from the air intake port.

6. The battery-powered power tool according to any one of claims 1 to 5,

the tool driving part is arranged at the front part of the shell, the peripheral wall is composed of a front side wall part, a rear side wall part and a left side wall part and a right side wall part, the air suction port is arranged at the rear side wall part, and the battery assembling part is arranged at the rear side wall part.

7. The battery-powered power tool according to any one of claims 1 to 6,

the housing is a rectangular parallelepiped shape extending in the front-rear direction, and the tool driving unit, the cooling fan, and the motor are arranged in the housing in the horizontal direction in this order from the front to the rear, and are mounted in the housing.

8. The battery-powered power tool according to any one of claims 1 to 7,

at least a part of a control circuit for controlling the motor is arranged between the motor and the air suction port,

the casing further includes a guide portion that leads the air sucked from the air inlet to the at least a part of the control circuit.

9. The battery-powered power tool according to any one of claims 1 to 8,

the battery-powered power tool further includes a motor holding member which is cylindrical and which holds the motor coaxially inside the motor holding member,

the air sucked from the air suction port passes through the motor holding member and then goes to the air discharge port.

10. The battery-powered power tool according to any one of claims 1 to 9,

the air outlet is arranged at a position adjacent to the cooling fan.

11. The battery-powered power tool according to any one of claims 1 to 10,

the battery mounting portion can mount the battery so as to be received in the width in the height direction of the case.

12. The battery-powered power tool according to any one of claims 1 to 11,

the battery-powered tool further includes a fixing member attached to the bottom wall of the housing for fixing the housing to the workpiece.

13. The battery-powered power tool of claim 12, wherein,

the bottom wall has a horizontal portion extending horizontally from the front to the rear and an inclined portion inclined rearward and downward from a rear end of the horizontal portion to extend to a rear end of the housing,

the fixing fitting is mounted to the horizontal portion,

the fixing member is provided with a stabilizer extending rearward to a lower side of the battery mounting portion.

14. The battery-powered power tool of claim 13, wherein,

the tool driving unit has a tool mounting portion at a lower end thereof to which a working tool is detachably mounted, and is displaceable between a retracted position at which the tool mounting portion is retracted into the housing and an extended position at which the tool mounting portion is extended downward from the housing.

15. The battery-powered power tool according to any one of claims 1 to 14,

the handle is displaceable between a holding position where the leg portion extends upward from the axis and the holding portion can be held by a user, and a storage position where the holding portion is stored in a recess provided in the top wall of the housing.

Technical Field

The present invention relates to a battery-type electric power tool, and more particularly, to a battery-type electric power tool having a structure in which a cooling fan disposed in a housing sucks external air into the housing to cool a member disposed in the housing.

Background

Conventionally, there have been known battery-powered electric tools such as a portable wire saw and a piercing machine that are driven by electric power supplied from a battery. In such a battery-powered electric tool, there is a technique of taking in outside air into the tool body by rotating a cooling fan disposed in the tool body by a motor in order to cool a heat generating body such as a motor and a control circuit in the tool body. Specifically, a heating element such as a motor or a control circuit is disposed between an intake port and an exhaust port provided in a tool body, and external air sucked from the intake port is blown onto the heating element to cool the heating element (patent document 1).

Prior art documents

Patent document

Patent document 1: japanese patent No. 4998846

Disclosure of Invention

Problems to be solved by the invention

In general, electric power tools are often used in environments with much dust and dirt. In addition, the present invention may be used in an environment wetted with water or oil. In particular, in the case of an electric tool such as a wire saw or a piercing machine that performs cutting, piercing, or other machining of a workpiece, chips of the workpiece are generated. When the electric power tool having the cooling structure as described above is used in such an environment, there are cases where: dust such as chips, water, oil, and the like scattered around the workpiece are sucked into the tool body through the air inlet together with the outside air, which causes a failure in the motor and the electric circuit in the tool body.

The present invention aims to provide a battery-powered electric tool that can suppress such dust and the like from being attracted into a tool body.

Means for solving the problems

That is, the present invention provides a battery-powered electric tool in which,

the battery-powered electric tool includes:

a housing having a bottom wall facing a workpiece during machining operation, a top wall located above the bottom wall, and a peripheral wall between the bottom wall and the top wall, the housing having an air inlet for taking air from outside the housing into the housing, and an air outlet for discharging air from the housing to outside the housing, and at least the air inlet being provided in the peripheral wall;

a motor mounted in the housing;

a tool driving unit mounted on the housing and driven by the motor;

a cooling fan which is installed in the housing and rotates with the rotation of the motor, and which sucks air outside the housing into the housing through the air inlet and discharges the air outside the housing through the air outlet to cool the housing; and

and a battery mounting portion that is provided on the peripheral wall of the casing and detachably mounts a battery that supplies electric power to the motor on an outer surface of the peripheral wall, wherein the battery mounting portion defines an air intake space that has an upward opening between the battery and a portion of the peripheral wall where the air intake port is provided when the battery is mounted, and draws air into the casing through the upward opening, the air intake space, and the air intake port when the cooling fan rotates.

In this battery-powered electric tool, the air sucked into the housing is mainly sucked from above, and therefore, particularly in the case of cutting a horizontally-placed workpiece from above, the suction of chips, dust, and the like scattered around the workpiece, a table, and the like, which are in the vicinity of the battery-powered electric tool in which work is performed, into the housing is suppressed. Further, by forming such an air intake space by the battery to be mounted, the shape of the case can be simplified as compared with a case where the same air intake space is formed in the case itself. In the present specification, terms such as "upper", "bottom wall", "top wall", and the like are used to define a relative positional relationship in the housing of the battery-powered electric tool, and are not used to specify an absolute position or direction with respect to the direction of gravity. For example, when the "bottom wall" is set to the upper side with reference to the vertical direction as the direction of gravity, the "ceiling wall" is set to the lower position of the "bottom wall", and the direction of the battery-powered electric tool does not necessarily coincide with the direction with reference to the vertical direction.

In the above battery-powered power tool, the battery mounting portion may have a bottom plate extending from the peripheral wall of the housing to at least partially cover a bottom surface of the mounted battery from below. When a horizontally placed workpiece is cut from above, the bottom plate is located at a position where the air intake space is shielded from the workpiece, work table, and the like, where chips and the like are scattered, and the chips and the like can be more reliably suppressed from being sucked into the housing.

The battery mounting portion may have a battery facing portion that contacts or approaches the mounted battery at a position below the air inlet to suppress air from flowing from below into the air intake space.

The air intake space may have a side opening that opens in at least either of the left and right directions to allow air to flow into the air intake space. Assisting in drawing air into the housing.

In addition, when the battery is mounted, the battery mounting portion may define an extended lower space continuous with the air intake space between the peripheral wall and the battery at a position extending downward from the air intake port. When the air flowing into the upward opening is sucked into the suction port while changing its direction, the dust falls into the extended lower space and is prevented from being sucked into the housing, taking into account the relatively heavy dust and the like that may be contained in the air flowing into the upward opening.

In the battery-powered electric tool of the present invention, the tool driving unit may be disposed at a front portion of the housing, the peripheral wall may be formed by a front side wall portion, a rear side wall portion, and left and right side wall portions, the air inlet may be provided in the rear side wall portion, and the battery mounting unit may be provided in the rear side wall portion. By setting the tool driving unit and the battery mounting unit in such a positional relationship, chips and the like can be more effectively sucked into the housing.

The housing may have a rectangular parallelepiped shape extending in the front-rear direction, and the tool driving unit, the cooling fan, and the motor may be arranged in the housing in the horizontal direction in this order from the front to the rear, and may be attached to the housing. Thus, the vertical width of the housing can be reduced, and the battery-powered electric tool can be made low in height.

In the battery-powered tool according to the present invention, at least a part of a control circuit for controlling the motor may be disposed between the motor and the air inlet, and the housing may further include a guide portion that allows air drawn from the air inlet to flow to the at least a part of the control circuit. This is to efficiently cool the control circuit generating heat.

The battery-powered power tool of the present invention may further include a motor holding member that is cylindrical and holds the motor coaxially inside the motor holding member, and the air sucked from the air inlet may pass through the motor holding member and then go to the air outlet. This is for forced cooling of the motor.

The exhaust port may be disposed adjacent to the cooling fan. This is to efficiently perform the exhaust to improve the cooling effect.

The battery mounting portion may be capable of mounting the battery so as to be received in the height-directional width of the case. This is for the purpose of reducing the height of the battery-powered electric tool.

The battery-powered power tool of the present invention may further include a fixing member attached to a lower surface side of the bottom wall of the housing for fixing the housing to the workpiece. When drilling a hole in a workpiece, the battery-powered power tool can be fixed to the workpiece to perform the drilling. The fixing member may be mechanically fixed, magnetically fixed, or the like.

In this case, the bottom wall may have a horizontal portion extending horizontally from the front to the rear and an inclined portion extending to the rear end of the case while being inclined rearward and downward from the rear end of the horizontal portion, the fixing metal fitting may be attached to the horizontal portion, and the stabilizer may be provided on the fixing metal fitting so as to extend rearward to the lower side of the battery mounting portion. Such a structure is intended to reduce the height of the battery-powered power tool. The stabilizer is used to prevent the battery-powered tool from being lifted from the workpiece due to a reaction force when the tool is pressed against the workpiece during operation of the battery-powered tool, and the stabilizer can protect the battery mounting portion even when the operator accidentally drops the battery-powered tool.

In this case, the tool driving unit may have a tool mounting portion to which the working tool is detachably mounted at a lower end thereof, and may be displaceable between a retracted position at which the tool mounting portion is retracted into the housing and an extended position at which the tool mounting portion is extended downward from the housing.

In the battery-powered electric tool according to the present invention, the housing may include an inverted U-shaped grip including a pair of legs and a grip portion extending between the legs, the pair of legs may be rotatably attached to the housing about an axis extending horizontally in a left-right direction of the housing, and the grip may be displaceable between a grip position at which the legs extend upward from the axis and the grip portion is graspable by a user and a storage position at which the grip portion is stored in a recess provided in the top wall of the housing. The battery-powered tool is easy to transport.

Hereinafter, embodiments of the battery-powered electric tool according to the present invention will be described with reference to the drawings.

Drawings

Fig. 1 is a side view of a battery-powered electric tool according to an embodiment of the present invention.

Fig. 2 is a sectional view taken along line II-II of fig. 1.

Fig. 3 is a sectional view taken along line III-III of fig. 2.

Fig. 4 is a perspective view of the battery-powered electric tool of fig. 1 with the battery removed.

Detailed Description

As shown in fig. 1, a battery-powered power tool 1 according to an embodiment of the present invention includes a tool body 10 and a fixing portion 12 attached to a lower side of the tool body 10. The battery 14 is detachably mounted to a rear portion of the tool body 10. The annular cutter (power tool) 16 is detachably attached to a front position of the tool body 10. The fixing portion 12 includes an electromagnet type fixing metal fitting 20 and a stabilizer 22 extending rearward from the electromagnet type fixing metal fitting 20. The battery-powered power tool 1 is a piercing machine that performs piercing of a metal workpiece by lowering a rotating ring cutter 16 by operation of a rod 18. In the piercing process, the tool body 10 is fixed to the workpiece by magnetically attracting the electromagnet-type fixing metal fittings 20 of the fixing portion 12 to the workpiece. In the piercing process, the front portion of the tool body 10 receives a force of being lifted upward by a reaction force received from the workpiece by the annular cutter 16 pressed against the workpiece, but the lifting is more reliably prevented by the stabilizer 22 coming into contact with the workpiece.

As shown in fig. 2 and 3, the tool body 10 includes a housing 24, a motor 26 disposed in the housing 24, a cooling fan 30 attached to a rotary shaft 28 of the motor 26, and a battery mounting portion 32 that mounts the battery 14 that supplies driving power to the motor 26. The motor 26 is disposed such that the rotation axis R thereof faces the front-rear direction (left-right direction as viewed in the drawing) of the tool body 10, and is held coaxially with the motor holding member 34 inside the motor holding member 34 that extends cylindrically in the front-rear direction in the housing 24. The rotary shaft 28 of the motor 26 is drivingly coupled to a tool driving unit 38 via a reduction gear mechanism 36. The tool driving portion 38 is formed as a cylindrical member that is rotatable about a vertically extending rotation axis and is vertically displaceable as a whole, and a tool mounting portion 40 for detachably mounting the annular cutter 16 is provided at a lower end thereof. The tool driving section 38 is moved up and down along with the turning operation of the lever 18 by a feed mechanism 44, and the feed mechanism 44 includes: a rack 42 extending in the vertical direction on the outer surface of the tool driving portion 38; and a pinion 41 attached to the rotation shaft of the lever 18 and engaged with the rack 42. The tool driving portion 38 is displaceable between a retracted position in which the tool attachment portion 40 is retracted into the housing 24 and an extended position in which the tool attachment portion 40 is extended downward from the housing 24. As shown in the drawing, the tool driving unit 38, the feeding mechanism 44, the reduction gear mechanism 36, the cooling fan 30, and the motor 26 are arranged in the housing 24 in this order from the front to the rear in the horizontal direction.

The housing 24 has a rectangular parallelepiped shape extending long in the front-rear direction as a whole. The housing has: a bottom wall 24-1 facing the workpiece when the fixing portion 12 is fixed to the workpiece and the piercing process is performed; a top wall 24-2 at an upper position opposite to the bottom wall 24-1; and a peripheral wall 24-3 between the bottom wall 24-1 and the top wall 24-2. The peripheral wall 24-3 includes a front side wall portion 24-4, a rear side wall portion 24-5, and left and right side wall portions 24-6 extending between the front side wall portion 24-4 and the rear side wall portion 24-5. As shown in fig. 3 and 4, the casing 24 has an air inlet 46 for sucking outside air into the casing 24 in a rear side wall portion 24-5 of the peripheral wall 24-3. As shown in fig. 2 and 4, the casing 24 has exhaust ports 48 for discharging the outside air sucked through the air inlet 46 in the left and right side wall portions 24-6 of the peripheral wall 24-3. The air inlet 46 is formed of a plurality of slit-shaped holes extending in the lateral direction, and is usually provided with a mesh filter 50. Further, a louver 52 extending obliquely upward toward the front is formed in the inner portion of the casing 24 of the air inlet 46. The louver 52 prevents water from entering through the air inlet 46. The exhaust port 48 is disposed to face obliquely rearward at a position adjacent to the cooling fan 30. In the illustrated example, the bottom wall 24-1 has a horizontal portion 24-1a extending rearward from the front position and an inclined portion 24-1b extending rearward and downward from the horizontal portion 24-1a and reaching the rear end of the case 24, the electromagnet type fixing member 20 is fixed to the horizontal portion 24-1a, and the stabilizer 22 passes below the inclined portion 24-1b and is positioned below the battery 14. As a result, the battery 14 is accommodated in the width of the housing 24 in the height direction, and the electromagnet-type fixing metal fitting 20 and the battery 14 are compactly accommodated in the vertical direction of the battery-type electric power tool 1. In the illustrated example, a handle 25 for carrying the battery-powered power tool 1 is provided on the housing 24. The handle 25 is formed in an inverted U shape including a pair of leg portions 25-1 and a grip portion 25-2 extending between the leg portions, the pair of leg portions 25-1 is rotatably attached to the housing 24 about an axis extending horizontally in the left-right direction, the handle 25 is displaceable between a grip position where the leg portions 25-1 extend upward and the grip portion 25-2 can be gripped by a user and a storage position where the grip portion 25-2 is stored in a recess 24-7 provided in the top wall 24-2 of the housing 24.

Within the housing 24, a control circuit 56 is also disposed for controlling the motor 26. The control circuit 56 has: a circuit board 58 disposed along the front-rear direction above the motor 26; an FET (electric field effect transistor) 60 disposed to extend downward from the circuit substrate 58; and a heat radiation fin 61 sandwiched by the FETs 60. The FET60 and the heat radiating fins 61, which are part of the control circuit 56, are located between the air inlet 46 and the motor 26. The FET60 is an electronic component for adjusting the power supplied from the battery 14 to the motor 26, and generates heat and reaches a high temperature when a relatively large current flows.

When the cooling fan 30 is rotated by the motor 26, the outside air is sucked into the casing 24 through the air inlet 46. The sucked air goes upward by the louver 52 and goes downward along the wall surface 62 in front thereof. A guide portion 64 inclined downward toward the front is formed at a position below the air inlet 46 in the casing 24, and the air sucked is guided by the guide portion 64 toward the FET60 of the control circuit 56 and the heat radiation fins 61. The air is blown to the heat-generated FET60 and the heat-radiating fins 61, and the FET60 and the heat-radiating fins 61 are cooled. The air having passed through the FETs 60 and the heat dissipating fins 61 passes between the stator 66 and the rotor 68 of the motor 26 in the motor holding member 34, thereby cooling the motor 26. The air passing between the stator 66 and the rotor 68 passes through the cooling fan 30 and is discharged from the exhaust port 48 to the outside of the housing 24. The air outlet 48 is directed obliquely rearward, so the air is discharged toward the rear. In this battery-powered electric tool 1, by introducing the outside air into the case 24 in this manner, the FET60 and the motor 26 that generate heat during driving can be efficiently cooled. By discharging air rearward from the air outlet 48, chips generated during the punching process by the ring cutter 16 are prevented from being lifted by the discharged air.

The battery mounting portion 32 has: a bottom plate 32-1 extending rearward from the bottom wall 24-1 of the case 24 to cover the bottom surface of the battery 14 from below; support side portions 32-2 extending rearward from left and right side wall portions 24-6 of the case 24 and supporting the battery 14 from both sides; a battery facing portion 32-3 extending vertically between the two support side portions 32-2 and substantially contacting the assembled battery 14; a terminal portion 32-4 provided at an intermediate position in the vertical direction of the battery facing portion 32-3 (fig. 4) and electrically connected to a connection terminal of the assembled battery 14; and a locking portion 32-6 having a surface 32-5 extending from the widthwise central position of the battery facing portion 32-3 to the height of the lower end of the air inlet 46 in a coplanar manner with the battery facing portion 32-3. On the right side surface of the locking portion 32-6 as viewed in fig. 4, a locking groove 32-7 that receives the locking portion of the battery (not shown) to lock the battery 14 to the battery mounting portion 32 is provided. The air intake opening 46 is provided at a position above the rear side wall portion 24-5 of the case 24 located forward of the battery facing portion 32-3, an air intake space 74 having an upward opening 74-1 opening upward is formed between the upper half of the rear side wall portion 24-5 where the air intake opening 46 is provided and the battery 14 in a state where the battery 14 is mounted in the battery mounting portion 32, and an extended lower space 76 continuing to the air intake space 74 is formed between the battery 14 and the rear side wall portion 24-5 at a position continuing downward from the air intake opening 46. In the illustrated example, the extended lower space 76 is provided so as to be opened laterally on both sides of the locking portion 32-6. The extended lower space 76 can store dust falling from the outside air that is switched in direction in the air intake space 74 and is sucked into the air inlet 46.

In the battery-powered electric tool 1, since the air intake space 74 that opens upward is formed between the battery 14 and the air inlet 46 as described above, the external air sucked through the air inlet 46 is mainly sucked from above and not from below. Therefore, suction of chips and the like scattered around the battery-powered power tool 1 during the punching operation can be suppressed. Further, by forming such an air intake space 74 by using the battery 14 detachably mounted, the shape of the case 24 can be simplified as compared with the case where the same air intake space 74 is formed only by the case 24. In this embodiment, the air intake space 74 has a side opening 74-2 that opens to the left and right to allow air to flow into the air intake space 74.

The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments. For example, in the above-described embodiment, the tool driving unit is disposed at the front portion of the tool main body, and the air inlet is disposed at the rear position, but another arrangement may be adopted in which the air inlet is disposed on any of the left and right side wall portions, for example. The fixing metal fitting may be fixed by another form such as vacuum suction or a vise without using an electromagnet, and the fixing portion does not necessarily need to be provided. Further, for example, a drill device using a drill as a power tool, or a battery-powered electric tool other than a drilling machine, such as a wire saw that drives a tool mounting portion up and down and uses a saw blade as a power tool, may be used.

Description of the reference numerals

1 Battery type electric tool

10 tool body

12 fixed part

14 cell

16 Ring cutter (working tool)

18 bar

20 electromagnet type fixing accessory

22 stabilizer

24 casing

24-1 bottom wall

24-1a horizontal part

24-1b inclined portion

24-2 top wall

24-3 peripheral wall

24-4 front side wall part

24-5 rear side wall part

24-6 side wall part

24-7 recess

25 handle

25-1 leg

25-2 grip part

26 Motor

28 rotating shaft

30 Cooling fan

32 Battery mounting part

32-1 bottom plate

32-2 support side

32-3 battery facing part

32-4 terminal portion

32-5 sides

32-6 locking part

32-7 locking groove

34 Motor holding member

36 reduction gear mechanism

38 tool drive

40 tool mounting part

41 pinion

42 rack

44 feeding mechanism

46 air inlet

48 air outlet

50 mesh filter

52 louver

56 control circuit

58 circuit board

60 FET (electric field effect transistor)

61 Heat radiating fin

62 wall surface

64 guide part

66 stator

68 rotor

74 air intake space

74-1 open upward

74-2 side opening

76 extended lower space

R axis of rotation.