Work equipment
The work machine's innovative intake opening layout and waterproof groove design prevent water entry into the motor housing, addressing the issue of motor damage from water ingress.
Patent Information
- Application Number
- JP2022037156
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-03-10
- Publication Date
- 2025-10-30
- Estimated Expiration
- 2042-03-10
AI Technical Summary
In work machines, water entering the motor housing can lead to motor damage due to adhesion, particularly when air intake openings allow water ingress along with external air flow.
The design includes a first air intake opening located above a second intake opening in the axial direction, with a tapered wall and waterproof groove to direct water away from the second intake, reducing water entry into the motor housing.
This configuration effectively minimizes water ingress into the motor housing, protecting the motor from damage even in wet conditions.
Smart Images
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Abstract
Description
[Technical Field]
[0001] The technology disclosed in this specification relates to a work machine. [Background technology]
[0002] Patent Document 1 discloses a work machine including a working unit and a main body having a motor housing. The main body includes a fan housed in the motor housing, and a motor housed in the motor housing for driving the working unit and the fan. A wall defining the motor housing, which is located on a first side of the motor in the axial direction of the motor, has an intake opening. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-210705 Summary of the Invention [Problem to be solved by the invention]
[0004] In the work machine of Patent Document 1, when the fan is driven, air flows from the outside of the main body into the motor housing through the intake opening. If water is present on the outer periphery of the main body, the water will enter the motor housing along with the air. If water enters the motor housing, the water may adhere to the motor.
[0005] This specification provides a technique that can prevent water from entering a motor housing in a work machine. [Means for solving the problem]
[0006] The working machine disclosed in this specification comprises a working unit and a main body portion having a motor accommodating portion, the main body portion comprising a fan accommodated in the motor accommodating portion, a motor accommodated in the motor accommodating portion and driving the working unit and the fan, and one or more first air intake openings, the motor accommodating portion being located on a first side of the motor in an axial direction of the motor and comprising a wall portion defining the motor accommodating portion and a second air intake opening provided in the wall portion, when the fan is driven, air outside the main body portion passes through the one or more first air intake openings and then the second air intake opening and flows into the motor accommodating portion, and when the working machine is in a working state, at least one of the one or more first air intake openings is located above the second air intake opening, and the one or more first air intake openings may be located on a second side of the second air intake opening that is opposite the first side in the axial direction.
[0007] According to the above configuration, water adhering to the outer peripheral surface of the main body flows into the first intake opening. The water that flows into the first intake opening adheres to the wall of the motor housing. The water that adheres to the wall of the motor housing flows from the second side to the first side in the axial direction. As it flows from the second side to the first side, the water flows downward. This reduces the amount of water that reaches the second intake opening. This prevents water from entering the motor housing. [Brief explanation of the drawings]
[0008] [Figure 1] 1 is a perspective view of a chainsaw 2 of a first embodiment as viewed from above and behind the left side. FIG. [Figure 2] FIG. 2 is a left side view of the chainsaw 2 of the first embodiment as viewed from the left. [Figure 3] 1 is a perspective view of a chainsaw 2 of a first embodiment as viewed from above and rear right. [Figure 4] 1 is a perspective view of the chainsaw 2 in the first embodiment, seen from above and behind the left, with the battery cover 50 and the battery pack 200 removed. FIG. [Figure 5] 1 is a perspective view of the chainsaw 2 in the first embodiment, seen from above and to the front right, with the battery cover 50 and the battery pack 200 removed. FIG. [Figure 6] 1 is a left cross-sectional view of a chainsaw 2 according to a first embodiment, as viewed from the left. [Figure 7] 1 is a front cross-sectional view of a chainsaw 2 according to a first embodiment, as viewed from the front. [Figure 8] 1 is a front cross-sectional view of a chainsaw 2 according to a first embodiment, as viewed from the front. [Figure 9] FIG. 2 is a perspective view of the fan 110 of the first embodiment as viewed from above on the front left. [Figure 10] FIG. 1 is a perspective view of the fan 110 in the first embodiment with the cover removed, as viewed from above and on the front left. [Figure 11] 2 is a front cross-sectional view of a fan 110 according to the first embodiment, as viewed from the front. FIG. [Figure 12] 1 is a perspective view of an inner housing 86, a fan 110, a duct 130, and a mounting unit 66 in the first embodiment, as viewed from above, rear, left. [Figure 13] 1 is a front cross-sectional view of a chainsaw 2 according to a first embodiment, as viewed from the front. [Figure 14] 1 is a perspective view of an inner housing 86, a motor unit 82, a duct 130, and a mounting unit 66 in the first embodiment, as viewed from above, rear right. FIG. [Figure 15] 1 is a perspective view of a battery pack 200 according to a first embodiment, as viewed from the front right below. [Figure 16] FIG. 10 is a front cross-sectional view of a chainsaw 302 according to a second embodiment, as viewed from the front. [Figure 17] FIG. 10 is a front cross-sectional view of a chainsaw 402 according to a third embodiment, as viewed from the front. [Figure 18] FIG. 10 is a top cross-sectional view of a chainsaw 402 according to a third embodiment, as viewed from the front. DETAILED DESCRIPTION OF THE INVENTION
[0009] Representative, non-limiting examples of the present invention will now be described in detail with reference to the drawings. This detailed description is intended simply to provide those skilled in the art with details for implementing preferred examples of the present invention, and is not intended to limit the scope of the present invention. In addition, additional features and inventions disclosed below can be used separately or in conjunction with other features and inventions to provide further improved work machines, methods of manufacturing and using the same.
[0010] Furthermore, the combinations of features and steps disclosed in the following detailed description are not essential to practicing the invention in its broadest sense, but are described solely to specifically illustrate exemplary embodiments of the invention. Furthermore, the various features of the exemplary embodiments described above and below, and those described in the independent and dependent claims, do not necessarily have to be combined in the exact embodiments described herein, or in the exact order listed, to provide additional and useful embodiments of the invention.
[0011] All features described in this specification and / or claims are intended to be disclosed individually and independently of one another as limitations on the original disclosure and claimed particulars, apart from any configuration of features described in the examples and / or claims. Furthermore, all numerical ranges and group or aggregation descriptions are intended to disclose intermediate configurations thereof as limitations on the original disclosure and claimed particulars.
[0012] In one or more embodiments, the work machine includes a working unit and a main body portion having a motor housing portion, the main body portion including a fan housed in the motor housing portion, a motor housed in the motor housing portion and driving the working unit and the fan, and a first air intake opening, the motor housing portion being located on a first side of the motor in an axial direction of the motor and including a wall portion defining the motor housing portion and a second air intake opening provided in the wall portion, when the fan is driven, air outside the main body portion passes through the first air intake opening and then the second air intake opening and flows into the motor housing portion, and when the work machine is in an operating state, the first air intake opening is located above the second air intake opening, and the first air intake opening may be located on a second side of the second air intake opening in the axial direction, opposite the first side in the axial direction.
[0013] In one or more embodiments, the wall portion may include a reduced diameter portion that reduces in diameter from the second side toward the first side in the axial direction, wherein the second intake opening is defined by an end of the reduced diameter portion on the first side, and a waterproof groove portion that is provided between the first intake opening and the second intake opening in the axial direction and is recessed from the outer peripheral surface of the wall portion.
[0014] According to the above configuration, water that passes through the first intake opening and travels down the narrowed portion of the wall enters the waterproof groove. The water that enters the waterproof groove flows downward without reaching the second intake opening. This reduces the amount of water that reaches the second intake opening. This further reduces the amount of water that enters the motor housing.
[0015] In one or more embodiments, the wall portion may further include a bellmouth portion disposed at the first end of the reduced diameter portion.
[0016] With this configuration, even if water that passes through the first intake opening and trickles down the narrowed portion of the wall passes through the waterproof groove, it is blocked by the bellmouth. This reduces the amount of water that reaches the second intake opening. This further reduces the amount of water that enters the motor housing.
[0017] In one or more embodiments, the main body portion may have a main body housing having the motor accommodating portion, and the first intake opening may be provided on an outer peripheral surface of the main body housing.
[0018] Let us assume that an air intake opening different from the first and second air intake openings is provided on the outer peripheral surface of the main housing. When the work machine is in operation, the different air intake opening is located higher than the second air intake opening and is located axially closer to the first air intake opening than the second air intake opening. In this case, it is necessary to provide a member for defining an air passage connecting the first air intake opening and the different air intake opening. With the above configuration, it is not necessary to provide a member for defining an air passage connecting the first air intake opening and the different air intake opening. Therefore, the configuration of the work machine can be simplified.
[0019] In one or more embodiments, the implement may be a chainsaw.
[0020] Chainsaws are sometimes used in environments where there is a possibility of water getting on the main body, such as in rainy weather. Therefore, even if water gets on the main body, it is necessary to prevent the water from entering the motor housing space. The above configuration is useful because it can prevent water from getting on the motor housing space.
[0021] (First Example) As shown in FIG. 1, the chainsaw 2 includes a main body 4, a guide bar 6, and a saw chain 8. The guide bar 6 is a long, thin, plate-like member attached to the main body 4 so as to protrude forward from the main body 4. The guide bar 6 is made of a metal material such as iron. The saw chain 8 includes a plurality of interconnected cutters and is attached along the periphery of the guide bar 6. In the following description, when the chainsaw 2 is placed on a horizontal mounting surface S such as the ground as shown in FIG. 2, the direction perpendicular to the mounting surface S is referred to as the up-down direction of the chainsaw 2, the direction obtained by projecting the longitudinal direction of the guide bar 6 onto the mounting surface S is referred to as the front-rear direction of the chainsaw 2, and the direction perpendicular to the up-down direction and the front-rear direction of the chainsaw 2 is referred to as the left-right direction of the chainsaw 2.
[0022] As shown in Figure 1, the main body 4 includes a main body housing 10, a front hand guard 12, a front handle 14, a sprocket cover 16 (see Figure 3), a battery storage section 18, a rear handle 20, and a rear hand guard 22. The main body housing 10 is made up of a left housing 24 and a right housing 26. The main body housing 10 has a generally rectangular parallelepiped shape with its longitudinal direction extending in the front-to-rear direction of the main body 4.
[0023] A front air intake section 30 that protrudes leftward is provided on the left surface of the left housing 24. The front air intake section 30 has a truncated cone section 32 and a flat plate section 34. The flat plate section 34 is provided at the left end of the truncated cone section 32. The diameter of the truncated cone section 32 increases from left to right. The truncated cone section 32 has a plurality of outer air intake openings 32a. The plurality of outer air intake openings 32a are arranged in a line in the circumferential direction of the truncated cone section 32. Each of the plurality of outer air intake openings 32a has an elongated hole shape, and has a longitudinal direction that follows the direction in which the generatrix of the truncated cone section 32 extends.
[0024] The front handle 14 includes a left-side fixing portion 14a extending leftward from the front lower portion of the left housing 24 (more specifically, the front intake portion 30), a left-side grip portion 14b extending upward from the left end of the left-side fixing portion 14a, an upper grip portion 14c extending rightward from the upper end of the left-side grip portion 14b, a right-side grip portion 14d extending rearward and downward from the right end of the upper grip portion 14c, and a right-side fixing portion 14e (see FIG. 3) extending downward from the lower end of the right-side grip portion 14d. The left-side fixing portion 14a is fixed to the front lower portion of the left housing 24 with a screw. As shown in FIG. 3, the right-side fixing portion 14e is fixed to the right housing 26 rearward of the sprocket cover 16 with a screw. The front hand guard 12 is rotatably supported on the front upper portion of the main housing 10. The front hand guard 12 is located forward of the front handle 14. The front hand guard 12 protects the user's hands when gripping the upper grip portion 14 c of the front handle 14 .
[0025] The rear handle 20 extends rearward and downward from the upper rear surface of the main body housing 10 and is bent downward. The rear hand guard 22 extends rearward from the lower rear surface of the main body housing 10 and is connected to the lower end of the rear handle 20. The rear hand guard 22 includes a first guard portion 22a located directly below the rear handle 20 and a second guard portion 22b extending rightward from the first guard portion 22a. The rear hand guard 22 protects the user's hands when gripping the rear handle 20.
[0026] A power button 40 is located on the upper surface of the rear handle 20 near the front end, allowing the user to switch the power of the chainsaw 2 on and off. A trigger lever 42 is located on the lower surface of the rear handle 20 near the front end, allowing the user to operate the rotational drive of the saw chain 8. A lock lever 44 is located on the upper surface of the rear handle 20, switching between a state in which the user is permitted to operate the trigger lever 42 and a state in which the user is prohibited from operating the trigger lever 42. When using the chainsaw 2, the user holds the chainsaw 2 by grasping the rear handle 20 with their right hand and the front handle 14 with their left hand. From this state, when the user presses down on the lock lever 44 of the rear handle 20 with the palm of their right hand, the user is permitted to operate the trigger lever 42. In this state, when the user pulls up the trigger lever 42 with the index finger of their right hand, the saw chain 8 is rotated.
[0027] The battery housing 18 is provided between the front handle 14 and the rear handle 20. The battery housing 18 includes an openable battery cover 50 and a battery interface (hereinafter, sometimes referred to as "IF") section 52 (see FIG. 4). As shown in FIG. 4, the battery IF section 52 includes an IF front surface 54, an IF right surface 56, an IF rear surface 58 (see FIG. 5), an IF left surface 60 (see FIG. 5), and an IF bottom surface 62. The IF front surface 54 extends along the left-right and up-down directions and faces rearward. The IF right surface 56 extends along the front-rear and up-down directions and faces leftward. The IF bottom surface 62 extends along the front-rear and left-right directions and faces upward. As shown in FIG. 5, the IF rear surface 58 extends along the left-right and up-down directions and faces forward. The IF left surface 60 extends along the front-rear and up-down directions and faces rightward.
[0028] As shown in FIG. 4, the IF front face 54 is provided with an IF-side intake opening 54a. As shown in FIG. 6, an intake pipe 64 is connected to the IF-side intake opening 54a. The intake pipe 64 is made of, for example, rubber. In a modified example, the intake pipe 64 may be made of resin or other materials. The intake pipe 64 includes a first air passage 64a extending forward from the IF-side intake opening 54a and a second air passage 64b bending from the front end of the first passage and extending downward. The opening of an end 64c of the second air passage 64b faces vertically downward. In this embodiment, the intake pipe 64 is attached to the IF front face 54 so that the opening of the end 64c faces vertically downward when the chainsaw 2 is in the state shown in FIG. 2. In a modified example, the intake pipe 64 may be rotatably attached to the IF-side intake opening 54a so that the opening of the end 64c faces vertically downward regardless of the state of the chainsaw 2.
[0029] As shown in FIG. 7, a right opening 56a is formed in the IF right surface 56. A mounting unit 66 is provided in the right opening 56a. As shown in FIG. 4, a first front rail 66a extending in the vertical direction is provided at the front end of the mounting unit 66, and a first rear rail 66b extending in the vertical direction is provided at the rear end. Five device-side terminals 68 are held by the mounting unit 66. The five device-side terminals 68 are provided between the first front rail 66a and the first rear rail 66b and are aligned in the front-rear direction. An inner exhaust hole 66c is provided at the bottom of the mounting unit 66. As shown in FIG. 7, an outer exhaust hole 66d is formed at the bottom of the rear surface of the mounting unit 66. A battery storage space BS is defined by the battery cover 50 and the battery IF section 52. As shown in FIG. 6, a seal member 53 is provided at the location where the battery cover 50 and the battery IF section 52 abut when the battery cover 50 is closed. Therefore, when the battery cover 50 is closed, the inside of the battery housing portion 18 is sealed.
[0030] As shown in Figure 6, a rear air intake opening 70 is provided at the lower rear surface of the main body housing 10. The rear air intake opening 70 has an elongated hole shape with its longitudinal direction along the left-right direction. A sponge 72 is attached to the rear air intake opening 70. The sponge 72 allows air to enter the interior of the main body housing 10 while preventing water and dust from entering the interior of the main body housing 10.
[0031] A control unit 80, a motor unit 82, an oil tank 84, and an inner housing 86 are arranged in the front interior of the main body housing 10. The control unit 80, the motor unit 82, and the oil tank 84 are arranged forward of the battery housing 18. The control unit 80 is arranged above the motor unit 82. The oil tank 84 stores lubricating oil for lubricating the saw chain 8. A motor housing 88 that houses the motor unit 82 is provided in the front interior of the main body housing 10. The motor housing 88 is defined by the left housing 24 (see FIG. 8), the right housing 26, the control unit 80, the oil tank 84, and the inner housing 86. A front exhaust opening 88a is formed in the front surface of the motor housing 88. The motor unit 82 is fixed to the left housing 24 with screws.
[0032] The motor unit 82 includes a motor cover 90 and a motor 92. The motor cover 90 has a waterproof structure. As shown in FIG. 8, the motor cover 90 includes a cover main body portion 94 and a lid portion 96. The cover main body portion 94 includes a main body side disc portion 94a, a first cylindrical portion 94b having a cylindrical shape, and a second cylindrical portion 94c having a cylindrical shape. A main body side opening 94e is provided in the center of the main body side disc portion 94a. The first cylindrical portion 94b extends leftward from the radially outer end of the main body side disc portion 94a. The second cylindrical portion 94c extends rightward from the outer peripheral end of the main body side opening 94e of the main body side disc portion 94a. The first cylindrical portion 94b is provided with a plurality of fins 94d extending radially outward. The lid portion 96 includes a lid side disc portion 96a. A lid-side circular opening 96b is provided in the center of the lid-side disk portion 96a. The lid-side disk portion 96a covers the opening at the left end of the first cylindrical portion 94b.
[0033] The motor 92 is waterproofed by a motor cover 90. The motor 92 is an inner rotor type DC brushless motor. The motor 92 includes a stator 100, a rotor 102 disposed inside the stator 100, and an output shaft 104 disposed to penetrate the center of the stator 100 and the rotor 102 and engaged with the rotor 102. The output shaft 104 extends along an axial direction A. The axial direction A is parallel to the left-right direction. The left end of the output shaft 104 is located to the left of the left end of the motor cover 90, and the right end of the output shaft 104 is located to the right of the right end of the motor cover 90. In other words, the output shaft 104 penetrates the motor cover 90 in the left-right direction. Multiple waterproof members 90a are provided in the motor cover 90 at the locations where the output shaft 104 penetrates.
[0034] A worm gear 105 and a sprocket 106 are fixed to the right end of the output shaft 104. The left end of the sprocket 106 is engaged with the worm gear 105, and a brake drum 107 is provided on the right end. A saw chain 8 (see FIG. 1) is stretched over the sprocket 106 from the guide bar 6. When the motor 92 is driven, the sprocket 106 rotates together with the output shaft 104, causing the saw chain 8 to rotate around the sprocket 106 and the guide bar 6. When the motor 92 is driven and the user pushes the front hand guard 12 (see FIG. 1) forward, the rotation of the output shaft 104 is braked via the brake drum 107.
[0035] A fan 110 is attached to the left end of the output shaft 104 via a bushing 108. As shown in FIG. 9, the fan 110 is a so-called closed fan. The fan 110 includes a fan disk 112, a plurality of blades 114, and a cover 116. A central opening 112a is provided in the center of the fan disk 112. The fan disk 112 has a cylindrical rib 112b extending forward from the outer circumferential edge of the central opening 112a. As shown in FIG. 10, the fan disk 112 and the plurality of blades 114 are integrally molded. The plurality of blades 114 extend leftward from the fan disk 112. When the fan 110 is viewed from the left, the radially inner ends of the plurality of blades 114 are shaped such that the radially outer ends are positioned clockwise relative to the radially inner ends. As shown in FIG. 9, the cover portion 116 is welded to the left end of the blade portion 114. A cover-side intake opening 116a is provided in the center of the cover portion 116. The diameter of the cover-side intake opening 116a is larger than the diameter of the central opening 112a. As shown in FIG. 11, a plurality of ventilation passages 110a are defined by the left surface of the fan disk portion 112, the right surface of the cover portion 116, and two blade portions 114 adjacent in the circumferential direction. As shown in FIG. 9, a plurality of fan exhaust openings 110b are defined on the outer peripheral surface of the fan 110 in the circumferential direction.
[0036] The inner housing 86 in FIG. 12 is fixed to the right housing 26 (see FIG. 1) with screws. As shown in FIG. 8, the left wall portion 86a of the inner housing 86 is provided with an inner air intake opening 120 and a waterproof portion 122. The waterproof portion 122 has a reduced-diameter portion 122a and a bell-mouth portion 122b. The reduced-diameter portion 122a has an outer diameter and an inner diameter that decrease from right to left. The bell-mouth portion 122b is provided at the left end of the reduced-diameter portion 122a. The bell-mouth portion 122b has a shape that does not obstruct the flow of air that flows from right to left along the outer peripheral surface of the left wall portion 86a and is drawn into the motor housing portion 88 via the inner air intake opening 120. The bell-mouth portion 122b defines the inner air intake opening 120. A waterproof groove portion 124 recessed from the outer peripheral surface of the left wall portion 86a is formed in the bell-mouth portion 122b. More specifically, the waterproof groove 124 is recessed radially inward from the outer circumferential surface of the left wall portion 86a. The depth D1 of the waterproof groove 124 is constant around the entire circumference.
[0037] As shown in FIG. 13, the inner air intake opening 120 is located a distance L1 to the left of the outer air intake opening 32a. The inner air intake opening 120 has a circular shape. The inner air intake opening 120 is located more inward than the outer air intake opening 32a. Here, "the inner air intake opening 120 is located more inward than the outer air intake opening 32a" means that air flowing from the outside of the chainsaw 2 to the inside passes through the outer air intake opening 32a and then the inner air intake opening 120. As shown in FIG. 8, the inner air intake opening 120 is located farther from the motor 92 than the outer air intake opening 32a in the left-right direction. As shown in FIG. 13, the vertical distance L2 between the lower end of the uppermost outer air intake opening 32a and the upper end of the waterproof groove portion 124 is within 10 cm.
[0038] As shown in FIG. 6, a duct 130 is accommodated inside the main body housing 10. As shown in FIG. 12, the duct 130 includes a fan-side end 132, a mounting unit-side end 134 (see FIG. 14), and a flow path 136 connecting the fan-side end 132 and the mounting unit-side end 134. As shown in FIG. 8, the fan-side end 132 is provided between the left surface of the left housing 24 and the left wall 86a of the inner housing 86. A fan-side opening 132a is formed in the fan-side end 132 of the duct 130. The fan-side opening 132a faces the inner air intake opening 120 of the inner housing 86. The opening area of the fan-side opening 132a is in the range of 1 / 3 to 1 / 2 times the opening area of the inner air intake opening 120. As shown in FIG. 14, the mounting unit-side end 134 of the duct 130 is attached to the lower part of the right surface of the mounting unit 66. As shown in FIG. 7, the mounting unit side end 134 is formed with a mounting unit side opening 134a.
[0039] As shown in FIG. 15, the battery pack 200 includes a battery housing 202. The battery housing 202 accommodates a plurality of battery cells C (see FIG. 7). The battery housing 202 includes a hook 204, a second front rail 206 provided at the front end of the battery housing 202, and a second rear rail 208 provided at the rear end of the battery housing 202. The second front rail 206 and the second rear rail 208 have shapes corresponding to the first front rail 66a and the first rear rail 66b (see FIG. 4) of the chainsaw 2, respectively. The hook 204 includes an engagement portion 204a and a hook operating portion 204b. The hook 204 is biased toward the outside of the battery housing 202 by a spring (not shown). When the battery pack 200 is attached to the battery IF unit 52 (see FIG. 4) of the chainsaw 2, the engaging portion 204a of the hook 204 enters the engaged portion 66e (see FIG. 7) of the mounting unit 66 of the chainsaw 2, thereby fixing the battery pack 200 to the battery IF unit 52. When the hook operating portion 204b is pressed in from this state, the engaging portion 204a comes out of the engaged portion 66e. In this state, the battery pack 200 can be slid relative to the battery IF unit 52, and the battery pack 200 can be removed from the battery IF unit 52 (i.e., the chainsaw 2).
[0040] A first battery vent 202a is formed in the lower part of the right surface of the battery housing 202. As shown in Fig. 7, when the battery pack 200 is attached to the chainsaw 2, the first battery vent 202a faces the inner exhaust hole 66c of the mounting unit 66. As shown in Fig. 15, a second battery vent 202b is formed in the left part of the front surface of the battery housing 202. When the battery pack 200 is attached to the chainsaw 2, the second battery vent 202b faces the IF-side air intake opening 54a (see Fig. 4) of the IF front surface 54 of the battery IF section 52.
[0041] Next, the airflow when the motor 92 of the chainsaw 2 is driven will be described. When the motor 92 in FIG. 8 is driven, the sprocket 106 and the fan 110 rotate. In this embodiment, the fan disk 112, blades 114, and cover 116 of the fan 110 rotate integrally. When the fan 110 is driven, air outside the main housing 10 passes through the outer air intake opening 32a of the left housing 24 and the inner air intake opening 120 of the inner housing 86 and is drawn into the motor housing 88. As shown in FIG. 6, the air that flows into the motor housing 88 passes around the motor cover 90. This cools the motor 92 inside the motor cover 90. The air flowing through the motor housing 88 also cools the control unit 80 that defines the motor housing 88. The air inside the motor housing 88 is then exhausted to the outside through the front exhaust opening 88a on the front surface of the motor housing 88.
[0042] Furthermore, when the fan 110 is driven, air within the battery housing 18 is drawn into the motor housing 88 via the duct 130. Specifically, as shown in FIG. 7, the air within the battery housing 18 passes through the second battery vent 202b (see FIG. 15) of the battery pack 200, the first battery vent 202a of the battery pack 200, the inner exhaust hole 66c of the mounting unit 66, the outer exhaust hole 66d of the mounting unit 66, and the mounting unit side opening 134a of the duct 130, before being drawn into the duct 130. The air flowing through the battery pack 200 cools the multiple battery cells C within the battery pack 200. As shown in FIG. 8, the air that has flowed into the duct 130 passes through the fan side opening 132a and the inner intake opening 120 of the inner housing 86, before being drawn into the motor housing 88. The air flow thereafter is the same as the air flow that flows in through the outer intake opening 32 a of the left housing 24 .
[0043] As described above, when the battery cover 50 is closed, the battery receptacle 18 is sealed. Therefore, if the motor 92 continues to be driven, a negative pressure state will be created inside the battery receptacle 18. In this case, as shown in FIG. 6 , air inside the main body housing 10 will be sucked into the battery receptacle 18. Specifically, the air inside the main body housing 10 passes through the intake pipe 64 and the IF-side intake opening 54a of the IF front surface 54 and is sucked into the battery receptacle 18.
[0044] Furthermore, as the motor 92 continues to be driven, a negative pressure state also develops inside the main body housing 10. In this case, air outside the main body housing 10 is drawn into the main body housing 10 through the rear air intake opening 70 provided at the bottom of the rear surface of the main body housing 10. The air that passes through the rear air intake opening 70 and flows into the main body housing 10 flows forward, passes through the air intake pipe 64 and the IF-side air intake opening 54a of the IF front surface 54, and flows into the battery receptacle 18. In this way, while the motor 92 is being driven, the motor 92, the control unit 80, and the multiple battery cells C in the battery pack 200 are cooled.
[0045] In one or more embodiments, as shown in FIGS. 1 and 8 , a chainsaw 2 (an example of a “working machine”) includes a saw chain 8 (an example of a “working unit”) and a main body 4 having a motor housing 88. The main body 4 includes a fan 110 housed in the motor housing 88, a motor 92 housed in the motor housing 88 and driving the saw chain 8 and the fan 110, and an outer air intake opening 32a (an example of a “first air intake opening”). The motor housing 88 includes an inner air intake opening 120 (an example of a “second air intake opening”) that is provided in a left wall 86a (an example of a “wall”) located to the left of the motor 92 in the axial direction A of the motor 92 (an example of a “first side”), and a front exhaust opening 88a (an example of an “exhaust opening”). When the fan 110 is driven, air flowing into the motor housing 88 from outside the main body 4 passes through the outer air intake opening 32a, the inner air intake opening 120, and the front exhaust opening 88a, in that order. When the chainsaw 2 is in an operating state (as shown in FIG. 2 ), the uppermost outer air intake opening 32a is located higher than the inner air intake opening 120, and the outer air intake opening 32a is located to the right (an example of the “second side”) of the inner air intake opening 120 in the axial direction A. With the above configuration, water adhering to the outer peripheral surface of the main body 4 flows into the outer air intake opening 32a. The water that flows into the outer air intake opening 32a adheres to the left wall 86a of the motor housing 88. The water that adheres to the left wall 86a of the motor housing 88 flows from the right to the left. As it flows from the right to the left, the water flows downward. This reduces the amount of water that reaches the inner air intake opening 120. This makes it possible to prevent water from entering the motor housing 88. The chainsaw 2 is sometimes used in environments where there is a possibility that water may adhere to the main body 4, such as in places where it is raining. For this reason, even if water adheres to the main body 4, it is necessary to prevent the water from entering the motor housing 88. The above configuration is useful in that it makes it possible to prevent water from entering the motor housing 88.
[0046] In one or more embodiments, as shown in FIG. 8 , the left wall portion 86a includes a tapered portion 122a whose diameter decreases from right to left in the axial direction A, with the left end of the tapered portion 122a defining the inner air intake opening 120, and a waterproof groove 124 recessed from the outer peripheral surface of the left wall portion 86a, located between the outer air intake opening 32a and the inner air intake opening 120 in the axial direction A. According to the above configuration, water that passes through the outer air intake opening 32a and trickles down the tapered portion 122a of the left wall portion 86a enters the waterproof groove 124. Water that enters the waterproof groove 124 trickles down from the waterproof groove 124. This reduces the amount of water that reaches the inner air intake opening 120. This further reduces water intrusion into the motor housing 88.
[0047] In one or more embodiments, as shown in FIG. 8 , the left wall portion 86a further includes a bellmouth portion 122b provided at the left end of the reduced diameter portion. With the above configuration, even if water that passes through the outer air intake opening 32a and trickles down the reduced diameter portion 122a of the left wall portion 86a passes through the waterproof groove portion 124, it is blocked by the bellmouth portion 122b. This makes it possible to further reduce the amount of water that reaches the inner air intake opening 120. This makes it possible to further prevent water from entering the motor housing portion 88.
[0048] In one or more embodiments, as shown in FIG. 8A , the main body 4 includes a main body housing 10 having a motor housing 88, and the outer air intake opening 32a is provided on the outer peripheral surface of the main body housing 10. As will be described in detail later, as shown in FIG. 14 , in a chainsaw 302 including an outer air intake opening 332a, a left air intake opening 332b provided to the right of the outer air intake opening 332a, and a right extension 334 defining an air passage connecting the outer air intake opening 332a and the left air intake opening 332b, the right extension 334 is necessary to prevent water from entering the motor housing 88. However, with the above-described configuration, the right extension 334 for defining the air passage connecting the left air intake opening 332b and the outer air intake opening 332a is not required. This simplifies the configuration of the chainsaw 2.
[0049] (Second Example) A chainsaw 302 of the second embodiment will be described with reference to Figure 16. In the chainsaw 2 of the second embodiment, the structure of the left housing 324 is different from the structure of the left housing 24 (see Figure 8) of the first embodiment. In the following, components common to the embodiments will be given the same reference numerals and descriptions thereof will be omitted.
[0050] The left housing 324 has a plurality of outer air intake openings 332a, a plurality of left air intake openings 332b located to the right of the outer air intake openings 332a, and a right extension 334 that defines an air passage connecting the outer air intake openings 332a and the left air intake openings 332b. In this embodiment, the outer air intake openings 332a and the left air intake openings 332b are arranged side by side in the front-to-rear direction. The outer air intake openings 332a and the left air intake openings 332b are located above the inner air intake openings 120.
[0051] According to the above configuration, water adhering to the outer peripheral surface of the main body 4 passes through the outer air intake opening 332a and the left air intake opening 332b (an example of a "first air intake opening") and adheres to the left wall 86a of the motor housing 88. The water adhering to the left wall 86a of the motor housing 88 flows from the right to the left. As it flows from the right to the left, the water flows downward. This reduces the amount of water that reaches the inner air intake opening 120. This prevents water from entering the motor housing 88.
[0052] (Third Example) A chainsaw 402 of the third embodiment will be described with reference to Figures 17 and 18. In the chainsaw 402 of the third embodiment, the structure of a left wall portion 486a of an inner housing 486 differs from the structure of the left wall portion 86a of the inner housing 86 of the first embodiment (see Figures 8 and 13).
[0053] As shown in FIG. 17 , the left wall portion 486a of the inner housing 486 is provided with an inner air intake opening 420 and a waterproof portion 422. The waterproof portion 422 has a reduced diameter portion 422a and a bellmouth portion 422b extending radially outward from the left end of the reduced diameter portion 422a. The outer and inner diameters of the reduced diameter portion 422a decrease from right to left. The bellmouth portion 422b is provided at the left end of the reduced diameter portion 422a. The bellmouth portion 422b defines the inner air intake opening 420. The bellmouth portion 422b is provided with a waterproof groove 424 recessed from the outer peripheral surface of the left wall portion 486a. Specifically, the waterproof groove 424 is recessed radially inward from the outer peripheral surface of the left wall portion 486a. The depth of the waterproof groove portion 424 is maximum at the top and bottom of the waterproof groove portion 424, D2. Also, as shown in FIG. 18, the depth of the waterproof groove portion 424 is minimum at the left and right sides of the waterproof groove portion 424, D3. The depth D3 is smaller than the depth D2. In this embodiment, the depth of the waterproof groove portion 424 varies along the circumferential direction. That is, the depth of the waterproof groove portion 424 is not constant around the entire circumference.
[0054] (First Modification) The "working machine" is not limited to the chainsaw 2, but may be a pole saw, a blower, a brush cutter, a hedge trimmer, a high-pressure washer, a sprayer, a lawn mower, a scarifier, a cultivator, or the like.
[0055] (Second Modification) The chainsaw 2 may have a waterproof groove portion to the right of the waterproof portion 122. The waterproof groove portion may be provided between the right end of the outer air intake opening 32a and the inner air intake opening 120 in the axial direction A.
[0056] (Third Modification) The chainsaw 2 does not have to have the waterproof portion 122. In this modification, the chainsaw 2 does not have the waterproof groove portion 124 either.
[0057] (Fourth Modification) The motor 92 may be a brushed DC motor or another type of motor such as an AC motor. [Explanation of symbols]
[0058] 2: Chainsaw 4: Main body 6: Guide bar 8: Saw chain 10: Main body housing 12: Front handguard 14: Front handle 14a: Left side fixed part 14b: Left side grip 14c: Upper grip part 14d: Right grip part 14e: Right side fixed part 16: Sprocket cover 18: Battery compartment 20: Rear handle 22: Rear handguard 22a: First guard section 22b: Second guard section 24: Left housing 26: Right housing 30: Front intake 32: Cone truncated part 32a: Outer intake opening 34: Flat plate part 40: Power button 42: Trigger lever 44: Lock lever 50: Battery cover 52: Battery IF section 53: Sealing material 54 :IF front 54a: IF side intake opening 56 :IF right side 56a: Right side opening 58:IF rear side 60:IF left side 62:IF bottom 64: Intake pipe 64a: First air passage 64b: Second air passage 64c: end 66: Mounting unit 66a: First front rail 66b: First rear rail 66c: Inner exhaust hole 66d:Outside exhaust hole 66e: Engaged part 68: Device side terminal 70: Rear intake opening 72: Sponge 80: Control unit 82: Motor unit 84: Oil tank 86: Inner housing 86a:Left wall part 88: Motor housing 88a: Front exhaust opening 90: Motor cover 90a: Waterproof material 92: Motor 94: Cover body 94a: Main body side disc part 94b: First cylindrical part 94c: Second cylindrical section 94d: Fin 94e: Main body side opening 96: Lid 96a: Lid side disc 96b: Circular opening on the lid side 100: Stator 102: Rotor 104: Output shaft 105: Worm gear 106: Sprocket 107: Brake drum 108: Bush 110: Fan 110a: Ventilation path 110b: Fan exhaust opening 112: Fan disc section 112a: Central opening 112b: Rib section 114: Blade 116: Cover part 116a: Cover side intake opening 120: Inner intake opening 122:Waterproof part 122a: Reduced diameter part 122b: Bell mouth part 124:Waterproof groove 130: Duct 132: Fan side end 132a: Fan side opening 134: Mounting unit side end 134a: Mounting unit side opening 136: Flow path section 200: Battery pack 202: Battery housing 202a: First battery vent 202b: Second battery vent 204: Hook 204a: Engagement part 204b: Hook operating part 206: Second front rail 208: Second rear rail 302: Chainsaw 324: Left housing 332a: Outer intake opening 332b: Left intake opening 334: Right extension part 402: Chainsaw 420: Inner intake opening 422: Waterproof section 422a: Reduced diameter part 422b: Bell mouth part 424:Waterproof groove 486: Inner housing 486a:Left wall part A: Axial direction BS: Battery storage space C: Battery cell S: Placement surface
Claims
1. A handheld work machine, A working section; a main body having a motor housing, The main body portion is a fan accommodated in the motor accommodating section; a motor housed in the motor housing portion and driving the working portion and the fan; one or more first intake openings; The motor accommodating portion is a wall portion that is located on a first side of the motor in an axial direction of the motor and that defines the motor accommodating portion; a second intake opening provided in the wall portion, When the fan is driven, air outside the main body passes through the one or more first air intake openings and the second air intake opening in this order, and then flows into the motor accommodating section, When the work machine is in a working state, at least one first air intake opening of the one or more first air intake openings is located above the second air intake opening, A work machine, wherein, in the axial direction, the one or more first intake openings are provided on a second side opposite the first side in the axial direction relative to the second intake opening.
2. The wall portion is a reduced diameter portion whose diameter decreases from the second side toward the first side in the axial direction, and an end portion of the reduced diameter portion on the first side defines the second intake opening; The work machine according to claim 1, further comprising: a waterproof groove portion provided between the first air intake opening and the second air intake opening in the axial direction and recessed from the outer peripheral surface of the wall portion.
3. The wall portion further comprises: The work machine according to claim 2 , further comprising a bell-mouth portion provided at an end of the first side of the reduced diameter portion.
4. The main body portion is a main body housing having the motor accommodating portion; The work machine according to claim 1 , wherein the first intake opening is provided on an outer peripheral surface of the main body housing.
5. The work machine according to claim 1 , wherein the work machine is a chainsaw.
Citation Information
Patent Citations
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