JP2015142443A - Work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work machine 1 on which a brushless motor 10 with a self-cooling fan 13 is loaded, which can protect a control substrate 28 for changing polarity of a driving current of the motor 10 from moisture, and which has excellent cooling properties of the control substrate 28.SOLUTION: In the work machine 1, a passage 24 for intake air flow by the self-cooling fan 13 is partitioned from a passage 23 of exhaust stream, and the intake air passage 24 includes a substrate cooling air passage 30 reaching from a suction port 25 opened toward the outward of the work machine 1 to the control substrate 28. The work machine is formed so that the suction port 25 is opened sideways or downward, and the substrate cooling air passage 30 reaches the control substrate 28 after extending upward from the suction port 25.

Description

  The present invention relates to a working machine using a brushless motor as a drive source, and more particularly to a working machine suitable for use in a moisture-rich environment such as an agricultural power sprayer.

  Some work machines use a brushless motor as a drive source. Some brushless motors have a fan (self-cooling fan) on the motor shaft to cool the motor itself. Further, Patent Documents 1 and 2 disclose that the polarity of the drive current of the brushless motor is changed. A work machine is described in which a control board is cooled by an air flow created by a self-cooling fan.

JP 2010-269409 A Utility Model Registration No. 3098140

  However, in the working machine described in Patent Document 1, since the air inlets of the cooling fan are arranged on the entire circumference of the casing of the working machine, the casing of the working machine is used during rainy weather or in a place with a lot of moisture. There is a concern that moisture will enter the inside and damage the motor itself and the control board.

  Further, since the control board is arranged in a wide space immediately inside the air inlet, the speed of the substrate cooling air taken in from the air inlet is slow, and the cooling of the control board is disclosed in Patent Document 1. There is also a problem that the nature is bad.

  Moreover, in the working machine described in Patent Document 2, since the motor is disposed on the wind of the cooling fan and the control board is disposed on the lee, air current from the cooling fan becomes warm air by cooling the motor itself, The control board is cooled by this warm air, and the cooling performance of the control board is poor.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a working machine capable of protecting a control board from moisture and having good cooling performance of the control board.

  In order to solve the above problems, a work machine according to the present invention includes a brushless motor with a self-cooling fan, an operating member driven by the brushless motor, and a control board for controlling the brushless motor, A work machine configured to cool both the brushless motor itself and the control board by an air flow created by the self-cooling fan, wherein an intake passage by the self-cooling fan is partitioned from an exhaust flow passage, The air intake passage includes a substrate cooling air passage extending from an air inlet opening toward the outside of the work machine to the control board, the air inlet opening sideways or downward, and the substrate cooling air passage is It is formed so as to reach the control board after extending upward from the air inlet (Claim 1).

  According to the present invention, since the intake port is opened sideways or downward, moisture such as rainwater hardly enters the substrate cooling air passage. In addition, since the substrate cooling air passage is formed so as to reach the control board after extending upward from the intake port, even if moisture has entered the substrate cooling air passage, It is easy to be naturally discharged from the intake port. Therefore, the control board can be prevented from being damaged by moisture.

  Note that the substrate cooling air passage is within the scope of the present invention not only when it extends right above the air inlet but also when it extends obliquely upward from the air inlet.

  Further, since the intake air flow passage by the self-cooling fan is partitioned from the exhaust air flow passage, the control board is always cooled by fresh outside air, and the cooling performance of the control board is improved. Further, since the intake flow passage and the exhaust flow passage are partitioned, both the intake flow and the exhaust flow flow smoothly without stagnation, so that the cooling performance of the control board and the brushless motor is improved. .

  As a preferred embodiment, the substrate cooling air passage may be bent after extending upward from the intake port, and the control substrate may be disposed downstream of the bent portion. 2). In this way, since the substrate cooling air collides with the inner wall of the substrate cooling air passage at the bent portion, moisture contained in the substrate cooling air is easily removed upstream of the control board. Therefore, the waterproof property of the control board is further improved.

  As a preferred embodiment, the substrate cooling air passage may include a folded portion (Claim 3). In this way, the substrate cooling air collides frontally with the inner wall of the substrate cooling air passage at the folded portion, so that moisture contained in the substrate cooling air is more easily removed upstream of the control board, and is waterproof. Is further improved.

  As one preferred embodiment, when the substrate cooling air passage has a portion extending obliquely or horizontally, the control board is disposed on the upper wall side of the oblique portion or the horizontal portion of the substrate cooling air passage. It is preferable in terms of waterproofing (Claim 4). This is because moisture does not easily accumulate on the control board.

  For the same reason, it is also effective to dispose at least a part of the substrate cooling air passage vertically and dispose the control substrate vertically in the vertical portion.

  As a preferred embodiment, the substrate cooling air passage may be a sealed passage in which a portion other than the air inlet is substantially closed (Claim 6). In this way, the air velocity of the substrate cooling air can be further increased, and the cooling performance of the control substrate is further improved.

  As an embodiment that contributes to improving the cooling performance of the control board, the control board is arranged such that the board cooling air flows along one side surface of the control board (Claim 7), or the board cooling It is also possible to adopt a mode (Claim 8) in which the control board is arranged such that wind flows along a heat sink provided on the control board.

  As a preferred embodiment, the control board wiring may be disposed outside the board cooling air passage (Claim 9). In this way, there is no adverse effect of moisture on the wiring of the control board.

  As a preferred embodiment, the substrate cooling air passage may be defined by one side surface of a battery that supplies power to the brushless motor. This is preferable because the battery is also cooled by the substrate cooling air when the battery is used while being heated by charging.

It is a side view of a backpack type power sprayer as an example of a working machine concerning one embodiment of the present invention. It is a top view of the power part of the backpack type power sprayer of FIG. It is an III-III arrow expanded sectional view of FIG. FIG. 4 is a cross-sectional view taken along arrow IV-IV in FIG. 2. It is a VV arrow sectional view of Drawing 4. It is explanatory drawing which simplified and showed a part of FIG. FIG. 5 is a simplified explanatory diagram illustrating a modification of FIG. 4. It is a simplified explanatory drawing of the principal part of other embodiment of this invention. It is a simplified explanatory drawing of the principal part of other embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  As a working machine according to an embodiment of the present invention, FIG. 1 shows a backpack type power sprayer.

  As shown in FIG. 1, a backpack-type sprayer 1 according to the present embodiment includes a backpack 2 and a pair of left and right backpack belts 3 and 3 on which a worker W carries the backpack 2. The worker W hangs the backpack belts 3 and 3 on his shoulders, carries the backpack 2 and carries out a spraying operation of, for example, a medicine on a vegetable or the like using a spray basket (not shown).

  The back body 2 includes a liquid tank 4 that stores the spray liquid, a gantry 5 that supports the liquid tank 4, and a power unit 6 that is mounted in the gantry 5. The liquid tank 4 is placed on the gantry 5 and fixed to the gantry 5 with screws or the like.

  FIG. 2 is a plan view of the gantry 5, and shows a plate-like bottom frame 7 constituting the gantry 5 and the power unit 6 disposed on the bottom frame 7. The gantry 5 has a square cylindrical peripheral wall 8 (see FIGS. 1 and 4) fixed on the bottom frame 7 so as to surround the power unit 6, but FIG. 2 shows the peripheral wall 8. It is a top view of the state removed.

  As shown in FIG. 2, the power unit 6 includes a pump 9 as an operating member, a brushless motor 10 that drives the pump 9, and a battery 11 that is a power source of the brushless motor 10. The pump 9 is driven by the brushless motor 10 to pump the sprayed liquid in the liquid tank 4 toward a spray nozzle (not shown) at the tip of the spray tank.

  The brushless motor 10 is a brushless motor 10 having a well-known self-cooling fan 13 in which a fan 13 is fixed on a motor shaft 12 in order to cool the motor itself. As shown in FIG. 3, which is a cross-sectional view taken along the line III-III in FIG. 2, the self-cooling fan 13 is fixed on the motor shaft 12 and disposed inside the motor case 14 of the brushless motor 10. .

  As shown in FIG. 2, an air inlet 15 and an air outlet 16 are formed at both ends of the peripheral surface of the motor case 14. As the self-cooling fan 13 rotates, outside air is sucked into the motor case 14 from the air inlet 15. The air taken into the motor case 14 flows through the motor case 14 by the rotation of the self-cooling fan 13, cools the inside of the motor 10, and is discharged from the air outlet 16. As shown in FIG. 3, the air discharged from the air outlet 16 is discharged to the outside (downward) of the sprayer 1 from an exhaust port 17 formed in the bottom frame 7.

  The brushless motor 10 is further covered with a motor cover 18 and has a double wall structure as a whole. The motor cover 18 defines a motor chamber 19 (FIG. 4) and imparts waterproof properties to the brushless motor 10. That is, since spray particles float around the sprayer 1 and the operator W during the spraying operation, these floating particles adhere to the surface of the liquid tank 4 and flow down as a water droplet on the surface of the liquid tank 4. . The motor cover 18 covers and protects the entire brushless motor 10 so that the brushless motor 10 is not affected even if these water droplets enter the frame 5.

  As shown in FIG. 2, the motor chamber 19 is partitioned by a partition 21 into an upstream chamber 22 on the air inlet 15 side and a downstream chamber 23 on the air outlet 16 side. The upstream chamber 22 communicates with an intake port 25 (see FIG. 4), which will be described later, via an intake passage 24, and the intake port 25, the intake passage 24, the upstream chamber 22, and the air inlet 15 allow intake flow to flow. A passage is formed. On the other hand, the downstream chamber 23 communicates with the exhaust port 17, and an exhaust flow path is formed by the air outlet 16, the downstream chamber 23, and the exhaust port 17. Since the flow path of the intake flow and the flow path of the exhaust flow are partitioned by the partition 21, the air in the downstream chamber 23 that has become high temperature by cooling the inside of the brushless motor 10 is transferred to the upstream chamber side 22. There is no inflow. Since fresh outside air is always introduced into the upstream chamber 22 from the intake port 25, the cooling performance of the brushless motor 10 is improved. Further, the provision of the partition 21 has an advantage that both the intake air flow and the exhaust air flow can flow smoothly without stagnation.

  Although not limited, in the example of FIG. 2, the partition 21 is provided integrally with the motor cover 18. As shown in FIG. 3, the motor cover 18 has, for example, a vertically divided structure, and an upper cover 27 can be attached to and detached from a lower cover 26 formed integrally with the bottom frame 7. Maintenance and inspection work in the motor chamber 19 is facilitated.

  As shown in FIG. 3, the downstream chamber 23 is defined by the motor cover 18, the partition 21, and the bottom frame 7, and the downstream chamber 23 communicates with the outside through the exhaust port 17. The warm air discharged from the air outlet 16 is smoothly discharged from the exhaust port 17 to the outside. The arrows in FIG. 3 indicate the flow of the exhaust flow.

  As shown in FIG. 4, the power unit 6 is provided with a control board 28 for controlling the brushless motor 10. The control board 28 connects the battery 11 and the brushless motor 10, controls the supply voltage from the battery 11, changes the polarity of the drive current of the brushless motor 10, etc. Control. As shown in FIGS. 2 and 4, the control board 28 is covered with a board cover 29 for reasons of waterproofing, as with the brushless motor 10. The substrate cover 29 covers and protects the control board 28 so that the control board 28 is not hindered even when water droplets caused by spray particles or the like enter the gantry 5.

  The control board 28 is separate from the brushless motor 10, connects the battery 11 and the brushless motor 10, and also has an effect of controlling the supply voltage from the battery 11. The control board 28 is also a heat generating member like the brushless motor 10 itself.

  Therefore, in the present embodiment, the control board 28 is cooled in addition to the brushless motor 10 itself by the air flow created by the self-cooling fan 13. For this purpose, as shown in FIG. 4, the intake passage 24 is extended upstream to form a substrate cooling air passage 30, and the control substrate 28 is disposed so as to face the substrate cooling air passage 30. .

  The substrate cooling air passage 30 reaches the control substrate 28 from the intake port 25 that opens downward of the sprayer 1, and then communicates with the upstream chamber 22 of the motor chamber 19. Since the control board 28 is cooled prior to the brushless motor 10 by fresh outside air continuously taken in from the intake port 25, the cooling performance of the control board 28 is improved.

  In the example of FIG. 4, the substrate cooling air passage 30 is defined using one side surface 11 a of the battery 11 that supplies power to the brushless motor 10, and the battery 11 is also cooled by the substrate cooling air. It is like that. For this reason, when the battery 11 is used in a state of being heated by charging, the battery 11 is also cooled by the substrate cooling air, which is preferable.

The battery 11 is detachable from a battery storage chamber 31 formed on the bottom frame 7, and a lid 32 for opening and closing the battery storage chamber 31 is rotatable on the mount 5. (See FIGS. 1 and 4).

  In the example of FIG. 4, a control board with a heat sink 33 in which a large number of plate-like heat radiation fins 34 are arranged in parallel is used as the control board 28. As shown in FIG. 5, the heat sink 33 is positioned in the substrate cooling air passage 30, and the control substrate 28 is arranged so that the substrate cooling air flows along the heat sink 33. However, the present invention is not limited to this, and as shown in FIG. 7, in the case of the control board 28 having no heat sink, the board cooling air flows in the board cooling air passage 30 so that the board cooling air flows along one side surface of the control board 28. It is also possible to arrange the control board 28.

  Further, since the control board 28 is an electronic device, it needs to be highly waterproof. For this reason, the control board 28 is sealed in a case filled with urethane resin to provide waterproofness, and only the heat sink 33 is exposed in order to improve cooling performance. Further, in the present embodiment, the following various measures are taken in order to further improve the waterproofness and cooling performance of the control board 28.

  In the example of FIG. 4, the air inlet 25 is formed in the bottom frame 7, and the air inlet 25 opens downward. This is to make it difficult for moisture to enter the substrate cooling air passage 30 in the sprayer 1 used in an environment with a lot of moisture in which the spray particles float.

  As shown in FIG. 4, the wiring 35 of the control board 28 is disposed outside the board cooling air passage 30. This is to prevent the wiring of the control board 28 from being adversely affected by moisture.

  FIG. 6 shows the substrate cooling air passage 30 in FIG. 4 in a simplified manner so that the features thereof can be easily understood.

  As is apparent from FIG. 6, the substrate cooling air passage 30 is formed so as to reach the control substrate 28 after extending upward from the intake port 25. For this reason, even if moisture enters the substrate cooling air passage 30, the moisture is easily discharged from the intake port 25. Therefore, the control board 28 can be prevented from being damaged by moisture.

  The substrate cooling air passage 30 is defined so as to be elongated with a wall surface 36 extending along the passage axis X. For this reason, a sufficient wind speed of the substrate cooling air is obtained in the substrate cooling air passage 30, and the cooling performance of the control board 28 by the substrate cooling air is improved.

  Further, the substrate cooling air passage 30 is bent (bent substantially at right angles in the example of FIG. 6) after extending upward from the intake port 25, and the control board 28 is disposed downstream of the bent portion 37. The By doing so, the substrate cooling air collides frontally with the front wall 37a of the substrate cooling air passage 30 at the bent portion 37, so that moisture contained in the substrate cooling air is easily removed upstream of the control board 28. Therefore, the waterproof property of the control board 28 is further improved. The removed water is naturally discharged from the intake port 25.

  In the example of FIG. 6, the substrate cooling air passage 30 includes a folded portion 38. In this way, since the substrate cooling air collides with the front wall 38a of the substrate cooling air passage 30 at the folded-back portion 38, the moisture contained in the substrate cooling air is more easily removed upstream of the control substrate 28. Further, waterproofness is further improved.

  The substrate cooling air passage 30 is formed so as to extend longer by being bent many times or provided with a folded portion, so that the substrate cooling air can collide with the wall many times. The effect of removing moisture in the cooling air can be enhanced.

  As shown in FIG. 6, by making the substrate cooling air passage 30 a sealed passage in which portions other than the air inlet 25 are substantially closed, the air velocity of the substrate cooling air can be further increased, and the control is performed. The cooling property of the substrate 28 can be further improved.

  Further, when the substrate cooling air passage 30 has a horizontally extending portion 39, it is preferable for waterproofing to arrange the control board 28 on the upper wall side of the horizontal portion 39 of the substrate cooling air passage 30. This is because moisture is unlikely to accumulate in the control board 28.

  For the same reason, it is also effective to dispose at least a part of the substrate cooling air passage 30 vertically and dispose the control substrate 28 vertically in the vertical portion 40 as shown in FIG. FIG. 7 shows a modification of FIG. 4 in a simplified manner as in FIG. 6. By providing a vertical partition 41 in the upstream chamber 22 of the motor chamber 19, a substrate cooling air passage is formed. It is a further extension from that of FIG. A control board 28 is disposed vertically in the vertical portion 40 of the board cooling air passage 30 which is additionally formed by providing the partition 41.

  8 and 9 show the main part of another embodiment of the present invention in a simplified manner as in FIG. 8 and 9 show various examples of the layout of the substrate cooling air passage 30 and the position of the control board 28 in the substrate cooling air passage 30.

  FIG. 8 is an example in which the intake port 25 is provided downward, as in the example of FIG. 6, and FIG. 9 is an example in which the intake port 25 is provided sideways. As described above, it is most preferable in terms of waterproofing to open the intake port 25 downward. However, even when the intake port 25 is opened laterally, there is an advantage over the upward opening, and a certain waterproof effect can be obtained.

  As shown in FIGS. 8 and 9, the substrate cooling air passage 30 preferably has a portion (which may be vertical or oblique) extending upward from the air inlet 25. This is because moisture adhering to the inner wall on the inlet side of the substrate cooling air passage 30 is naturally discharged. From the viewpoint of the spontaneous discharge of moisture, as shown in FIGS. 8A and 8C, it is most preferable that all of the substrate cooling air passage 30 extends upward from the air inlet 25 to the control substrate 28. .

  Further, it is preferable that at least one bent portion 37 is provided in the middle of the substrate cooling air passage 30, and the control substrate 28 is disposed downstream of the bent portion 37. This is because when the substrate cooling air hits the front wall 37a at the bent portion 37, moisture contained in the substrate cooling air is removed. If the angle of bending is a right angle or more, it is more preferable because the substrate cooling air collides with the wall of the substrate cooling air passage in front.

  As shown in FIGS. 8 (f), 9 (b) and 9 (c), it is also preferable to provide a folded portion 38 in the substrate cooling air passage 30. In this case, the substrate cooling air collides frontally with the front wall 38a at the folded-back portion 38, so that moisture contained in the substrate cooling air is more easily removed on the wind of the control board 28, and the waterproof property is improved. It is because it improves further.

  As shown in FIGS. 8B, 8C, 8D, 9G, and 9C, control is performed when the substrate cooling air passage 30 has a portion extending obliquely or horizontally. It is preferable in terms of waterproofing that the substrate 28 is disposed on the oblique wall 42 or the horizontal wall 39 of the substrate cooling air passage 30. This is because moisture does not easily accumulate on the control board. For the same reason, at least a part of the substrate cooling air passage 30 is vertically arranged as shown in FIGS. It is also effective to arrange the control board 28 vertically.

  8 (d), (e), (f), and FIG. 9 (b), when there is a portion where moisture easily collects in the vicinity of the control board 28 due to the layout of the board cooling air passage 30. It is preferable to provide a drain hole 43 on the lower wall surface of the passage.

  As an example of the working machine according to the present invention, not only the back-loaded power sprayer 1 shown in FIG. 1 but also a stationary power sprayer or a pump device may be mentioned. Moreover, it is suitable to apply to various working machines used outdoors, such as a power brush cutter and a hedge trimmer.

1 Working machine 9 Actuating member (pump)
DESCRIPTION OF SYMBOLS 10 Brushless motor 11 Battery 11a One side of battery 13 Self-cooling fan 16, 23, 17 Exhaust flow passage 24 Intake passage 25 Intake port 28 Control board 30 Substrate cooling air passage 33 Heat sink 35 Wiring 37 Bending portion 38 Folding portion 39 Horizontal portion 40 Vertical part 42 Diagonal part

Claims (10)

  A brushless motor (10) with a self-cooling fan (13), an operating member (9) driven by the brushless motor (10), a control board (28) for controlling the brushless motor (10), A working machine (1) that cools both the brushless motor (10) itself and the control board (28) by an air flow created by the self-cooling fan (13), The intake passage (24) by the self-cooling fan (13) is partitioned from the exhaust flow passages (16, 23, 17), and the intake passage (24) opens toward the outside of the work machine (1). A substrate cooling air passage (30) extending from the air inlet (25) to the control board (28) is provided, the air inlet (25) opens sideways or downward, and the substrate cooling air passage (30) is the air intake. Mouth (25) It is formed so as to extend to the control substrate after extending Luo upward (28), the working machine.   The substrate cooling air passage (30) is bent after extending upward from the air inlet (25), and the control substrate (28) is disposed leeward of the bent portion (37). The working machine described.   The working machine according to claim 1 or 2, wherein the substrate cooling air passage (30) includes a folded portion (38).   The substrate cooling air passage (30) has a portion extending obliquely or horizontally, and the control substrate (28) is an upper wall of the oblique portion (42) or the horizontal portion (39) of the substrate cooling air passage (30). The working machine according to claim 1, 2, or 3 disposed on a side.   The at least one part of the said board | substrate cooling air channel | path (30) is arrange | positioned perpendicularly | vertically, The said control board (28) is arrange | positioned vertically long in this perpendicular | vertical part (40), The Claim 1, 2, or 3 Work machine.   The working machine according to any one of claims 1 to 5, wherein the substrate cooling air passage (30) is formed as a sealed passage in which a portion other than the air inlet (25) is substantially closed.   The work machine according to any one of claims 1 to 6, wherein the control board (28) is arranged such that a substrate cooling air flows along one side surface of the control board (28).   The control board (28) is arranged according to any one of claims 1 to 6, wherein the control board (28) is arranged such that a substrate cooling air flows along a heat sink (33) arranged on the control board (28). Work machine.   The work machine according to any one of claims 1 to 8, wherein the wiring (35) of the control board (28) is disposed outside the board cooling air passage (30).   10. The substrate cooling air passage (30) is defined by one side surface (11a) of a battery (11) that supplies electric power to the brushless motor (10). Work machine.

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