Cleaning device

Abstract

A cleaning device includes a motor, a switch, a tip connection portion, a plurality of first claws, and a control portion. The front end connecting part can be connected with the front end accessory and is rotated by the driving force of the motor. The plurality of first claws are disposed on the tip connection portion along the circumferential direction of the rotation axis of the tip connection portion. The plurality of first claws engage with a plurality of second claws of the tip attachment in response to rotation of the tip connection portion in the forward direction, and are separated from the plurality of second claws in response to rotation of the tip connection portion in the reverse direction. When the motor rotates in the reverse direction, the control unit stops the motor on the basis of a condition that a first condition related to the rotation state of the front end connecting part is satisfied.

Description

Technical Field

[0001] The invention relates to a cleaning device for installing a rotating front end attachment. Background Art

[0002] The washer described in Japanese Patent Publication No. 7-327897 has: a motor, and a motor adapter fixed to the shaft of the motor, and can be installed with a rotating cleaning member. The rotating cleaning member has three locking flanges, and the motor adapter has three locking claws. The rotating cleaning member is installed on the motor adapter by engaging the three locking flanges with the three locking claws. The user rotates the motor in the opposite direction, so that the engagement between the three locking flanges and the three locking claws is released. Furthermore, the user can remove the rotating cleaning member from the motor adapter without using hands. Summary of the invention

[0003] Sometimes, the user may not notice that the motor rotates in the reverse direction and use the scrubber. As a result, the rotating cleaning member may be separated from the scrubber during operation, resulting in interruption of the operation. In addition, if the rotating cleaning member is separated from the scrubber during operation, the rotating cleaning member may hit a person or an object.

[0004] One aspect of the present invention is preferably to provide a cleaning device that is prevented from being used while a motor is rotating in the reverse direction.

[0005] A cleaning device according to one embodiment of the present invention is capable of installing a front-end attachment, and comprises: a motor, an operating switch, a front-end connection part, a plurality of first claws, and a control part. The operating switch is manually operated to switch the rotation direction of the motor to forward or reverse. The front-end connection part is configured to be connectable to the front-end attachment and rotated by the driving force of the motor. The plurality of first claws are arranged on the front-end connection part along the circumferential direction of the rotation axis of the front-end connection part. The plurality of first claws engage with the plurality of second claws corresponding to the rotation of the front-end connection part in the forward direction, and separate from the plurality of second claws corresponding to the rotation of the front-end connection part in the reverse direction. The plurality of second claws are provided on the front-end attachment. The control part controls the drive of the motor. During the reverse rotation of the motor, the control part stops the motor based on the fact that the first condition related to the rotation state of the front-end connection part is satisfied.

[0006] A cleaning device according to one embodiment of the present invention stops the motor when the motor rotates in the reverse direction based on the first condition related to the rotation state of the front end connecting portion being satisfied. Therefore, it is possible to prevent the user from using the cleaning device without noticing that the motor is rotating in the reverse direction.

[0007] A control method for a motor of a cleaning device in another embodiment of the present invention comprises the following steps: rotating the motor in the reverse direction so that a plurality of first claws are separated from a plurality of second claws, wherein the plurality of first claws are arranged on the front end connecting portion along the circumferential direction of the rotation axis of the front end connecting portion, the front end connecting portion is configured to be connectable to a front end attachment and rotated by the driving force of the motor, the plurality of second claws are provided on the front end attachment, and the plurality of first claws engage with the plurality of second claws corresponding to the rotation of the motor in the forward direction; and stopping the motor based on the fact that a prescribed condition related to the rotation state of the front end connecting portion has been satisfied during the reverse rotation of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a figure which shows the external appearance of the cleaning device which concerns on 1st Embodiment.

[0009] Figure 2 It is a diagram showing a display unit of the cleaning device according to the first embodiment.

[0010] Figure 3 It is a diagram showing a front end attachment connected to the cleaning device according to the first embodiment.

[0011] Figure 4 It is a diagram showing the bottom surface of the distal end attachment according to the first example of the first embodiment.

[0012] Figure 5A It is a figure which shows the lower surface of the front-end|tip connection part of the cleaning device concerning 1st Embodiment.

[0013] Figure 5B It is a perspective view showing the front end connection portion of the cleaning device according to the first embodiment.

[0014] Figure 6 This is a diagram showing a state in which the front end attachment according to the first example is connected to the front end connection portion of the cleaning device according to the first embodiment.

[0015] Figure 7 It is a figure which shows the bottom surface of the front-end|tip attachment concerning the 2nd example of 1st Embodiment.

[0016] Figure 8 This is a diagram showing a state in which the front end attachment according to the second example is connected to the front end connection portion of the cleaning device according to the first embodiment.

[0017] Fig. 9 It is a figure which shows the engagement angle between the 1st claw of the cleaning device which concerns on 1st Embodiment, and the 2nd claw of a brush.

[0018] Fig.10 It is a diagram showing a cross section along the radial direction of the first claw of the cleaning device according to the first embodiment.

[0019] Fig.11 It is a diagram showing a cross section along the radial direction of a first claw of the cleaning device according to the first embodiment and a second claw engaged with the first claw.

[0020] Fig.12 It is a figure which shows the cross section along the circumferential direction of the first claw of the cleaning device which concerns on 1st Embodiment.

[0021] Fig.13 It is a diagram showing a cross section along the circumferential direction of a first claw of the cleaning device according to the first embodiment and a second claw engaged with the first claw.

[0022] Fig.14 This is a block diagram showing the electrical configuration of the cleaning device according to the first embodiment.

[0023] Fig.15 This is a flowchart showing a main process executed by the microcomputer of the cleaning device according to the first embodiment.

[0024] Fig.16 This is a flowchart showing an interruption process executed by the microcomputer of the cleaning device according to the first embodiment.

[0025] Fig.17 This is a flowchart showing a switch operation detection process executed by the microcomputer of the cleaning device according to the first embodiment.

[0026] Fig.18 This is a flowchart showing a power management process executed by the microcomputer of the cleaning device according to the first embodiment.

[0027] Fig.19 This is a flowchart showing the main power supply off state determination process executed by the microcomputer of the cleaning device according to the first embodiment.

[0028] Fig. 20 This is a flowchart showing the automatic shutoff determination process of the main power supply state executed by the microcomputer of the cleaning device according to the first embodiment.

[0029] Fig.21 This is a flowchart showing a motor control process executed by the microcomputer of the cleaning device according to the first embodiment.

[0030] Fig. 22 This is a flowchart showing a speed mode setting process executed by the microcomputer of the cleaning device according to the first embodiment.

[0031] Fig.23AThis is a flowchart showing a first part of a rotation direction setting process executed by the microcomputer of the cleaning device according to the first embodiment.

[0032] Fig. 23B This is a flowchart showing the second part of the rotation direction setting process executed by the microcomputer of the cleaning device according to the first embodiment.

[0033] Fig.23C This is a flowchart showing the third part of the rotation direction setting process executed by the microcomputer of the cleaning device according to the first embodiment.

[0034] Fig.24 This is a flowchart showing a first example of a process of acquiring the rotation angle of the front end connecting portion executed by the microcomputer of the cleaning device according to the first embodiment.

[0035] Fig.25 This is a flowchart showing a second example of the process of acquiring the rotation angle of the front end connecting portion executed by the microcomputer of the cleaning device according to the first embodiment.

[0036] Fig.26 This is a flowchart showing a first example of the automatic return determination process to the forward rotation executed by the microcomputer of the cleaning device according to the first embodiment.

[0037] Fig. 27 This is a flowchart showing a second example of the automatic return determination process to the forward rotation executed by the microcomputer of the cleaning device according to the first embodiment.

[0038] Fig.28 This is a flowchart showing a third example of the automatic return determination process to the forward rotation executed by the microcomputer of the cleaning device according to the first embodiment.

[0039] Fig.29 This is a flowchart showing the automatic recovery determination process based on the second rotation angle executed by the microcomputer of the cleaning device according to the first embodiment.

[0040] Fig.30 This is a flowchart showing an automatic recovery determination process based on the number of times the cleaning device is driven during reverse rotation, which is executed by the microcomputer of the cleaning device according to the first embodiment.

[0041] Fig.31 This is a flowchart showing the state transition process executed by the microcomputer of the cleaning device according to the first embodiment.

[0042] Fig.32 This is a flowchart showing a rotation angle calculation process executed by the microcomputer of the cleaning device according to the first embodiment.

[0043] Fig.33This is a flowchart showing the inverter control process executed by the microcomputer of the cleaning device according to the first embodiment.

[0044] Fig.34 This is a diagram showing target rotation speeds corresponding to speed patterns of the motor of the cleaning device according to the first embodiment.

[0045] Fig.35 This is a flowchart showing the third part of the rotation direction setting process executed by the microcomputer of the cleaning device according to the second embodiment.

[0046] Fig.36 This is a flowchart showing a first example of the pressure determination process executed by the microcomputer of the cleaning device according to the second embodiment.

[0047] Fig.37 This is a flowchart showing a second example of the pressure determination process executed by the microcomputer of the cleaning device according to the second embodiment.

[0048] Fig.38 This is a flowchart showing the state transition process executed by the microcomputer of the cleaning device according to the second embodiment.

[0049] Fig.39 This is a diagram showing the output duty ratio and the rotation angle of the motor during and after the pressing determination when the front attachment is pressed against the ground according to the second embodiment.

[0050] Fig.40 It is a diagram showing the output duty ratio and the rotation angle of the motor during and after the pressing determination when the front attachment is not pressed against the ground according to the second embodiment. DETAILED DESCRIPTION

[0051] (Summary of Implementation Methods)

[0052] In one embodiment, there can be provided a cleaning device having at least one of the following features 1 to 7 and to which a front end attachment can be mounted.

[0053] Feature 1: Motor.

[0054] Feature 2: The switch is manually operated to switch the rotation direction of the motor between forward and reverse.

[0055] Feature 3: A front end attachment can be connected and the front end connection portion is configured to rotate by the driving force of the motor.

[0056] · Feature 4: A plurality of first claws are arranged at the distal end connecting portion along the circumferential direction of the rotation axis of the distal end connecting portion.

[0057] Feature 5: The plurality of first claws engage with the plurality of second claws in response to the front end connecting portion rotating in the forward direction, and separate from the plurality of second claws in response to the front end connecting portion rotating in the reverse direction.

[0058] ·Feature 5.5: A plurality of second claws are provided on the front end attachment.

[0059] ·Feature 6: The control unit is configured to control the driving of the motor.

[0060] Feature 7: The control unit stops the motor when the motor is rotating in the reverse direction based on the fact that a first condition related to the rotation state of the distal end connecting portion is satisfied.

[0061] The cleaning device having at least features 1 to 7 stops the motor when the motor rotates in the reverse direction based on the first condition related to the rotation state of the front end connection portion being satisfied. Therefore, it is possible to prevent the user from using the cleaning device without noticing that the motor is rotating in the reverse direction.

[0062] In one embodiment, in addition to or instead of at least any one of the above-mentioned features 1 to 7, at least one of the following features 8 and 9 may be included.

[0063] Feature 8: The first condition is satisfied when the distal end connecting portion is rotated in the reverse direction by an angle equal to or greater than the engagement angle.

[0064] Feature 9: The engagement angle corresponds to a region in which (i) the first claw overlaps with the second claw and (ii) an engagement force is generated between the first claw and the second claw, the first claw being included in the plurality of first claws and the second claw being included in the plurality of second claws.

[0065] The cleaning device having at least features 1 to 9 stops the motor when the first condition is satisfied, thereby making it possible to detach the front attachment from the cleaning device and to prevent the user from using the cleaning device while the motor is rotating in the reverse direction.

[0066] In one embodiment, in addition to or instead of at least any one of the above-mentioned features 1 to 7, at least one of the following features 10 to 11 may be included.

[0067] Feature 10: The first condition is satisfied when the distal end connecting portion rotates in the reverse direction for a predetermined time, and the predetermined time corresponds to the rotation speed of the motor and the engagement angle.

[0068] Feature 11: The engagement angle corresponds to a region in which (i) the first claw overlaps with the second claw and (ii) an engagement force is generated between the first claw and the second claw, the first claw being included in the plurality of first claws and the second claw being included in the plurality of second claws.

[0069] The cleaning device having at least features 1 to 7, 10, and 11 stops the motor when the first condition is satisfied, thereby making it possible to remove the front attachment and prevent the user from using the cleaning device while the motor is rotating in the reverse direction.

[0070] In one embodiment, the following feature 12 may be provided in addition to or in place of at least one of the features 1 to 11 described above.

[0071] Feature 12: The control unit changes the rotation direction to the forward direction based on the fact that a second condition related to the driving state of the motor is satisfied while the motor is rotating in the reverse direction.

[0072] The cleaning device having at least features 1 to 9 and 12 or features 1 to 7 and 10 to 12 returns the rotation direction of the motor to the forward direction after the front attachment is removed from the front connection portion. Thus, the user can use the cleaning device without paying attention to the rotation direction of the motor the next time he uses the cleaning device.

[0073] In one embodiment, in addition to or in place of at least one of the above-mentioned features 1 to 12, the following feature 13 may be provided.

[0074] Feature 13: The second condition is satisfied when the front end connecting portion rotates in the reverse direction by an angle equal to or greater than the engagement angle while the motor is subjected to a load equal to or greater than a load threshold.

[0075] The cleaning device having at least features 1 to 9, 12 to 13, or features 1 to 7, 10 to 13, causes the front end attachment to rotate in the reverse direction while receiving a reaction force from the ground, thereby releasing the engagement between the plurality of first claws and the plurality of second claws. When the front end attachment receives a reaction force from the ground, the motor receives a load. Therefore, by stopping the motor based on the fact that the second condition is satisfied, the front end attachment can be more appropriately removed from the front end connection portion.

[0076] In one embodiment, in addition to or instead of at least any one of the above-mentioned features 1 to 13, at least one of the following features 14 to 16 may be included.

[0077] Feature 14: The second condition is satisfied when the number of driving times is equal to or greater than a predetermined number of times.

[0078] Feature 15: The number of times the motor has been driven in the reverse direction.

[0079] Feature 16: One drive corresponds to a period from when the motor starts rotating to when it stops rotating.

[0080] The cleaning device having at least features 1 to 9, 12, 14 to 16, or features 1 to 7, 10 to 12, 14 to 16 can more reliably release the engagement between the plurality of first claws and the plurality of second claws by rotating the motor in the reverse direction a plurality of times. Therefore, by stopping the motor based on the satisfaction of the second condition, the front end attachment can be more appropriately detached from the front end connection portion.

[0081] In one embodiment, in addition to or instead of at least any one of the above-mentioned features 1 to 16, at least one of the following features 17 and 18 may be included.

[0082] Feature 17: The control unit acquires a signal indicating whether the front end attachment mounted on the front end connecting portion via the plurality of first claws is pressed against the ground, based on the fact that the rotation direction is switched to the reverse direction by the operation switch.

[0083] Feature 18: The control unit immediately stops the motor based on the fact that the acquired signal indicates that the front attachment is not pressed against the ground.

[0084] In a cleaning device having at least features 1 to 7, 17, and 18, the front end attachment is rotated in the reverse direction while being pressed against the ground and receiving a reaction force from the ground, thereby the front end attachment is detached from the front end connection portion. In a case where the rotation direction has been switched to the reverse direction but the front end attachment is not pressed against the ground, the user may mistakenly believe that the rotation direction has been switched to the forward direction, thereby possibly starting work with the cleaning device. Based on the situation where the rotation direction has been switched to the reverse direction and the front end attachment is not pressed against the ground, the motor is immediately stopped, thereby being able to more appropriately suppress the situation where the user uses the cleaning device while the motor is rotating in the reverse direction.

[0085] In one embodiment, in addition to or instead of at least any one of the above-mentioned features 1 to 18, at least one of the following features 19 to 21 may be included.

[0086] Feature 19: The present invention is configured as a drive circuit for controlling a voltage applied to the motor.

[0087] Feature 20: When the rotation direction is switched to the reverse direction by operating the switch, the control unit (i) controls the drive circuit so that the first voltage is applied to the motor and (ii) acquires a signal.

[0088] Feature 21: The control unit controls the drive circuit so as to apply a second voltage higher than the first voltage to the motor based on the acquired signal indicating that the front attachment is pressed against the ground.

[0089] In a cleaning device having at least features 1 to 7 and 17 to 21, during the acquisition of the signal, the torque of the motor can be suppressed to a level where the motor cannot rotate by overcoming the load borne by the motor. Furthermore, in response to the acquisition of the signal indicating that the front-end attachment is installed on the ground, the torque of the motor is increased so that the motor can rotate by overcoming the load. Therefore, the user can safely remove the front-end attachment from the front-end connection portion.

[0090] In one embodiment, in addition to or instead of at least any one of the above-mentioned features 1 to 21, at least one of the following features 22 and 23 may be included.

[0091] Feature 22: When the rotation direction is switched to the reverse direction by operating the switch, the control unit (i) controls the drive circuit so as to apply a pulse width modulation signal having a first duty ratio to the motor, and (ii) acquires the signal.

[0092] Feature 23: The control unit gradually increases the first duty ratio based on the fact that the acquired signal indicates that the front attachment is pressed against the ground.

[0093] In the cleaning device having at least features 1 to 7 and 17 to 23, the voltage applied to the motor can be increased based on the fact that the front attachment is pressed against the ground.

[0094] In one embodiment, in addition to or instead of at least one of the above-mentioned features 1 to 21, the following feature 24 may be provided.

[0095] Feature 24: The control unit acquires a signal based on the rotation state of the motor.

[0096] In the cleaning device having at least features 1 to 7, 17, 18, and 24, when the front attachment is pressed against the ground, the motor does not rotate due to the reaction force from the ground. When the front attachment is not pressed against the ground, there is no load applied to the motor from the ground, so the motor rotates. Therefore, the control unit can obtain a signal based on the rotation state of the motor.

[0097] In one embodiment, the above features 1 to 24 can be combined arbitrarily.

[0098] In one embodiment, any one of the above features 1 to 24 may be deleted.

[0099] (First embodiment)

[0100] <1. Structure>

[0101] <1-1. Overall structure>

[0102] Reference Figure 1 The structure of the cleaning device 1 is described. The cleaning device 1 is used for polishing operations such as cleaning or waxing the floor. The cleaning device 1 involved in the present embodiment is a handheld device. The cleaning device 1 includes: a main body 10, a rod 11, a support portion 6, a head 5, and a front end connection portion 30. The rod 11 has a rod-like shape or a cylindrical shape, and extends in the up and down direction. The main body 10 has a cylindrical shape with a larger diameter than the rod 11, and extends in the up and down direction. The main body 10 is arranged on the rod 11, and the rod 11 is accommodated therein. In addition, the main body 10 accommodates a controller 50 (see Fig.14 ).

[0103] The main body 10 includes a first gripping portion 12 formed in a T-shape at the upper end of the main body 10. The first gripping portion 12 is gripped by a user of the cleaning device 1. The main body 10 includes a trigger 14 disposed at a rear surface position of the first gripping portion 12. The trigger 14 is configured to be pulled by the hand gripping the first gripping portion 12. In response to the trigger 14 being pulled by the user, a trigger signal indicating that the switch is on is output to a microcomputer (microcomputer) 60 described later. In response to the trigger 14 being released by the user, a trigger signal indicating that the switch is off is output to the microcomputer 60.

[0104] The main body 10 includes a display unit 155 on the surface of the first grip 12. The main body 10 also includes an operation unit 150 below the display unit 155. The display unit 155 and the operation unit 150 are electrically connected to the microcomputer 60 via wires passing through the inside of the main body 10. Figure 2 The operation unit 150 and the display unit 155 are shown in FIG.

[0105] The operating unit 150 includes a main power supply / speed mode switching switch 153. The main power supply / speed mode switching switch 153 is operated by the user to (i) turn the main power supply of the cleaning device 1 on or off, and (ii) select the speed mode of the motor 70. In response to the main power supply / speed mode switching switch 153 being pressed by the user, a main power supply signal indicating that it is turned on is output to the microcomputer 60. When the on state of the main power supply signal continues for more than a specified time, the main power supply is switched from on to off, or from off to on. In addition, when the main power supply signal is switched from on to off before the on state of the main power supply signal continues for more than a specified time, the speed mode is switched from the set mode to the next mode. The speed mode is switched in the order of low speed mode → medium speed mode → high speed mode → low speed mode.

[0106] That is, each time the user long-presses the main power / speed mode switching switch 153, the main power is switched between on and off. Long-pressing means that the user continuously presses the main power / speed mode switching switch 153 for a predetermined time or longer. The user turns on the main power and pulls the trigger 14 to turn on the motor 70 (see Fig.14 ) is driven. The user stops the motor 70 by disconnecting the main power supply or releasing the trigger 14.

[0107] In addition, each time the user short presses the main power / speed mode switching switch 153, the speed mode is switched in the order of low speed mode → medium speed mode → high speed mode → low speed mode. Short press means that the user releases the main power / speed mode switching switch 153 after pressing the main power / speed mode switching switch 153 and before a specified time has passed.

[0108] The operation unit 150 includes a reverse mode switch 154. In response to the user pressing the reverse mode switch 154, a reverse mode signal indicating that the switch is turned on is output to the microcomputer 60. As a result, the rotation direction of the motor 70 is switched from the forward direction to the reverse direction. Hereinafter, the rotation of the motor 70 in the forward direction is referred to as forward rotation, and the rotation of the motor 70 in the reverse direction is referred to as reverse rotation.

[0109] The display unit 155 includes a speed display unit 151. The speed display unit 151 includes three light emitting diodes (LEDs) corresponding to the high speed mode, the medium speed mode, and the low speed mode. Among the three LEDs of the speed display unit 151, the LED corresponding to the speed mode set by the main power supply / speed mode switching switch 153 is lit. In addition, the speed display unit 151 flashes the three LEDs during the process of the motor 70 rotating in the reverse direction.

[0110] The display unit 155 includes an error display unit 152. The error display unit 152 includes one LED, and lights up when the microcomputer 60 detects an error that requires protection of the cleaning device 1 or the battery pack 40.

[0111] The main body 10 includes a battery assembly portion 41 on the upper surface of the main body 10 and on the rear side of the first grip portion 12. A detachable battery pack 40 is slidably mounted on the battery assembly portion 41. The battery pack 40 mounted on the battery assembly portion 41 is electrically connected to the controller 50. The battery pack 40 includes a secondary battery that can be charged and discharged. The secondary battery is, for example, a lithium ion battery and includes a plurality of battery cells connected in series.

[0112] The main body 10 includes a second grip 13 at the front surface and the lower end of the main body 10. The second grip 13 is formed in a rectangular shape and protrudes forward from the front surface of the main body 10. The second grip 13 is gripped by a user.

[0113] The support portion 6 is attached to the lower end of the rod portion 11. The support portion 6 has a two-branch shape with a lower side separated.

[0114] The head 5 is disposed under the support 6 and is supported by the two forks of the support 6. The head 5 has a motor 70 and a speed reduction mechanism 75 (see Fig.14 In the present embodiment, the motor 70 is a three-phase brushless motor. The speed reduction mechanism 75 is connected to the rotating shaft 77 of the motor 70 to reduce the rotation speed of the motor 70 and output it. The motor 70 is electrically connected to the controller 50 by a wire passing through the rod 11 and the inside of the main body 10.

[0115] The front end connection part 30 is formed in a disk or cylindrical shape and is arranged at the lower end of the head 5. The front end connection part 30 has a load shaft 80. The load shaft 80 is connected to the rotating shaft 77 of the motor 70 by means of a speed reduction mechanism 75. Therefore, the front end connection part 30 receives the driving force of the motor 70 and rotates. That is, when the motor 70 rotates in the forward direction, the front end connection part 30 rotates in the forward direction, and when the motor 70 rotates in the reverse direction, the front end connection part 30 rotates in the reverse direction. The front end attachment 20 is detachably mounted on the lower surface of the front end connection part 30. The front end connection part 30 will be described in detail later.

[0116] The front attachment 20 is a tool for grinding the floor or the like, and has a disc-shaped member. The front attachment 20 is attached to the front connection portion 30 so that the center of the disc-shaped member coincides with the load shaft 80. The front attachment 20 is, for example, a brush or a cushion. The brush is formed by attaching a bundle of hair to a disc-shaped member made of resin. A pad formed into a disc shape by a nonwoven fabric of nylon or polyester is fixed to the cushion. In the present embodiment, the front attachment 20 is a brush.

[0117] <1-2. Configuration of the front end connection and front end attachment>

[0118] Reference Figures 3 to 13 , the structure of the front end connection part 30 and the front end attachment 20 will be described. Figure 3 The top surface of the front end attachment 20 is shown. The front end attachment 20 includes a first annular portion 21, a second annular portion 28, and a third annular portion 22. The first annular portion 21 is an outermost annular member, and a hair bundle is mounted on the lower surface of the first annular portion 21. The second annular portion 28 is an annular member adjacent to the radial inner side of the first annular portion 21, and is located below the first annular portion 21. The second annular portion 28 has ribs 235, 245, 255. The ribs 235, 245, 255 are arranged at equal intervals along the circumferential direction of the second annular portion 28. The second annular portion 28 is fixed to the first annular portion 21 by screws with the aid of the ribs 235, 245, 255. The third annular portion 22 is an annular member adjacent to the radially inner side of the second annular portion 28 , and is located above the second annular portion 28 .

[0119] The third annular portion 22 is provided with second claws 23, 24, 25 that engage with first claws 33, 34, 35 described later. The second claws 23, 24, 25 are arc-shaped plate-like members and are arranged at equal intervals so as to protrude radially inward along the circumferential direction of the load shaft 80, i.e., the circumferential direction of the third annular portion 22.

[0120] exist Figure 4The first example of the lower surface of the second annular portion 28 and the third annular portion 22 is shown. The second claws 23, 24, and 25 have the same shape as each other. The second claw 23 includes: a protrusion 231, a first area 232, and a second area 233. The protrusion 231 is arranged at the center position of the circumferential direction of the second claw 23 and protrudes downward. The first area 232 is: an area at the positive rotation side position relative to the protrusion 231. The second area 233 is: an area at the reverse rotation side position relative to the protrusion 231. Similarly, the second claw 24 includes: a protrusion 241, a first area 242, and a second area 243, and the second claw 25 includes: a protrusion 251, a first area 252, and a second area 253. A gap 261 is formed between the second claw 23 and the second claw 24 , a gap 262 is formed between the second claw 24 and the second claw 25 , and a gap 263 is formed between the second claw 25 and the second claw 23 .

[0121] exist Figure 5A as well as Figure 5B The bottom surface of the front end connecting portion 30 is shown. The front end connecting portion 30 includes an outer annular portion 31 and an inner annular portion 38. The outer annular portion 31 is an annular member disposed at an outer position. The inner annular portion 38 is an annular member adjacent to the radial inner side of the outer annular portion 31 and disposed at a position lower than the outer annular portion 31.

[0122] The first claws 33, 34, 35 are mounted on the inner annular portion 38. The first claws 33, 34, 35 are plate-like members having an arc shape and are arranged at equal intervals so as to protrude radially outward along the circumferential direction of the rotating shaft 77, that is, the circumferential direction of the inner annular portion 38. The first claws 33, 34, 35 have the same shape as each other. The size of the first claws 33, 34, 35 is smaller than the gaps 261, 262, 263.

[0123] The first claws 33, 34, 35 are arranged at a position lower than the outer annular portion 31. The ends of the first claws 33, 34, 35 on the reverse rotation side in the circumferential direction are connected to the outer annular portion 31. The ends of the first claws 33, 34, 35 on the normal rotation side in the circumferential direction are separated from the outer annular portion 31. That is, there is a gap between the ends on the normal rotation side and the outer annular portion 31 in the up-down direction.

[0124] exist Figure 6The lower surface of the front end connecting part 30 is shown in a state where the second claws 23, 24, 25 are engaged with the first claws 33, 34, 35. When the front end attachment 20 is placed on the ground, the first claws 33, 34, 35 are passed through the gaps 261, 262, 263, and the front end connecting part 30 is rotated in the forward direction, so that the second claws 23, 24, 25 are engaged with the first claws 33, 34, 35. Specifically, the second region 233 of the second claw 23 enters from the end of the forward rotation side of the first claw 33 and the end of the forward rotation side of the first claw 33 contacts the protrusion 231 of the second claw 23, so that the second claw 23 is engaged with the first claw 33. When the second claw 23 is engaged with the first claw 33, the second region 233 is sandwiched between the outer annular portion 31 and the first claw 33. Similarly, the second claw 24 engages with the first claw 34 , and the second claw 25 engages with the first claw 35 .

[0125] By rotating the front end connection part 30 in the reverse direction at an angle corresponding to the engagement angle Af, the first claws 33, 34, 35 are separated from the second claws 23, 24, 25 and move toward the positions of the gaps 261, 262, 263. As a result, the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25 is released, and the front end attachment 20 can be removed from the front end connection part 30.

[0126] The engagement angle Af is smaller than the overlap angle A4. Figure 6 As shown, the overlapping angle A4 corresponds to the area where each of the first claws 33, 34, 35 overlaps with each of the second claws 23, 24, 25. That is, the overlapping angle A4 corresponds to the angle of the arc-shaped area where each of the first claws 33, 34, 35 overlaps with each of the second claws 23, 24, 25.

[0127] exist Figure 7 The second example of the lower surface of the second annular portion 28 and the third annular portion 22 is shown. The second claws 23, 24, 25 involved in the second example are smaller than the second claws 23, 24, 25 involved in the first example. Figure 8 As shown in FIG. 1 , the overlapping angle A4 of the second example is smaller than the overlapping angle A4 of the first example. That is, the overlapping angle A4 changes according to the shape of the front attachment 20 .

[0128] Reference Fig. 9, the calculation method of the overlap angle A4 is described. The first angle A1 is: the interval between the protrusion 231 and the protrusion 251, and is 360 / N degrees. N is the number of the first claws. In the present embodiment, the first angle A1 is 120 degrees. The second angle A2 is: the angle corresponding to the circumferential width of the rib 255, for example, 10 degrees. The larger the second angle A2 is, the smaller the overlap angle A4 is. The third angle A3 is: the angle corresponding to the margin of the gap 263 relative to the first claw 35, for example, 10 degrees. The larger the third angle A3 is, the smaller the overlap angle A4 is. When the third angle A3 is 0 degrees, it will be difficult to mount the front end attachment 20 on the front end connection portion 30.

[0129] The overlapping angle A4 is calculated by overlapping angle A4=(first angle A1-second angle A2-third angle A3) / 3. By rotating the front end connecting portion 30 in the opposite direction at an angle greater than the overlapping angle A4, the engagement between each of the first claws 33, 34, 35 and each of the second claws 23, 24, 25 is released. However, in reality, the entire region corresponding to the overlapping angle A4 does not generate an engagement force (or a bonding force) between each of the first claws 33, 34, 35 and each of the second claws 23, 24, 25. A portion of the entire region corresponding to the overlapping angle A4 generates an engagement force, and the remaining portion serves as an insertion guide for the second region 233, 243, 253. The engagement angle Af corresponds to the region in which the engagement force is generated between the first claws 33, 34, 35 and the second claws 23, 24, 25 in the region corresponding to the overlapping angle A4. That is, the engagement angle Af corresponds to a region where each of the first claws 33 , 34 , 35 overlaps each of the second claws 23 , 24 , 25 and an engagement force is generated between each of the first claws 33 , 34 , 35 and each of the second claws 23 , 24 , 25 .

[0130] exist Fig.10 FIG. 2 shows a cross section of the first claw 33 along the radial direction. The upper surface of the first claw 33 is inclined at an angle BA relative to a plane perpendicular to the vertical direction. Accordingly, the interval between the first claw 33 and the outer annular portion 31 narrows from the inner side to the outer side in the radial direction. Fig.11 As shown, when the second region 233 of the second claw 23 enters between the first claw 33 and the outer annular portion 31, the first claw 33 bends downward to clamp the second region 233 between the first claw 33 and the outer annular portion 31. Thus, an engaging force is generated between the first claw 33 and the second claw 23.

[0131] exist Fig.12The cross section of the first claw 33 along the circumferential direction is shown. The first claw 33 has a first part and a second part. The first part is inclined at an angle BB relative to a plane perpendicular to the up-down direction, and is located closer to the positive rotation side than the second part. The second part is parallel to the plane perpendicular to the up-down direction, and is connected to the outer annular portion 31. The interval between the first part and the outer annular portion 31 widens from the boundary with the second part toward the end on the positive rotation side. The first part plays the role of an insertion guide for the second claw 23. As shown in FIG. Fig.13 As shown, when the second region 233 of the second claw 23 enters from the end of the first portion, the second region 233 interferes with the first portion, and an engaging force is generated between the first claw 33 and the second claw 23. The engaging angle Af is an angle corresponding to the region where the engaging force is generated. The engaging angle Af is smaller than the overlapping angle A4. In the present embodiment, the engaging angle Af is half of the overlapping angle A4.

[0132] Therefore, by rotating the front end connecting portion 30 in the reverse direction at an angle greater than the engagement angle Af and less than 360 degrees, the engagement between each of the first claws 33, 34, 35 and each of the second claws 23, 24, 25 is released. Preferably, by rotating the front end connecting portion 30 in the reverse direction at an angle greater than the overlap angle A4 and less than 360 degrees, the engagement between each of the first claws 33, 34, 35 and each of the second claws 23, 24, 25 is released.

[0133] <1-3. Electrical configuration>

[0134] Reference Fig.14 The electrical structure of the cleaning device 1 is shown. The cleaning device 1 includes: a motor 70, a speed reduction mechanism 75, a front end connection portion 30, and a position sensor 65. The position sensor 65 includes three Hall sensors. The three Hall sensors are arranged corresponding to the three-phase winding of the motor 70. Whenever the rotor of the motor 70 rotates by 60 degrees in electrical angle, the three Hall sensors will output position signals to the microcomputer 60 in sequence. In addition, in other embodiments, the motor 70 can be a brushed motor. In this case, the cleaning device 1 may not have the position sensor 65.

[0135] The cleaning device 1 also includes a controller 50. The controller 50 includes a power supply control circuit 52, a regulator 53, a microcomputer 60, a first data communication unit 61, a second data communication unit 62, a gate circuit 55, an inverter circuit 56, a disconnect switch 59, a battery voltage detection unit 63, a current detection circuit 57, and a temperature detection circuit 58.

[0136] The power control circuit 52 is connected to the positive electrode of the battery pack 40, and controls the regulator 53 based on the power control signal and the main power signal. The power control signal is output from the battery pack 40 and indicates on or off. The on of the power control signal corresponds to: the remaining capacity of the battery pack 40 is greater than the prescribed amount, and the off of the power control signal corresponds to: the remaining capacity of the battery pack 40 is less than the prescribed amount. When the power control signal is on and the main power is on, the power control circuit 52 causes the regulator 53 to generate power to be supplied to each circuit of the controller 50. When the power control signal is off or the main power is off, the power control circuit 52 stops the regulator 53.

[0137] The inverter circuit 56 is connected to the positive electrode of the battery pack 40 via the disconnect switch 59. The inverter circuit 56 is a full bridge circuit having three switching elements on the low side and three switching elements on the high side. The switching element is, for example, MOSFET. The disconnect switch 59 is a switching element such as MOSFET.

[0138] The gate circuit 55 controls the on / off of each switch element of the inverter circuit 56 based on the motor control signal input from the microcomputer 60. The inverter circuit 56 applies a voltage corresponding to the on / off of each switch element to the three-phase winding of the motor 70. In addition, the gate circuit 55 controls the on / off of the cut-off switch 59 based on the switch control signal input from the microcomputer 60. When the cut-off switch 59 is on, the inverter circuit 56 is connected to the battery pack 40 and receives power from the battery pack 40. When the cut-off switch 59 is off, the electrical connection between the inverter circuit 56 and the battery pack 40 is cut off.

[0139] The battery voltage detection unit 63 detects a battery voltage value, and outputs the detected battery voltage value to the microcomputer 60. The battery voltage value corresponds to the magnitude of the output voltage of the battery pack 40.

[0140] The current detection circuit 57 detects the battery current value and outputs the detected battery current value to the microcomputer 60. The battery current value corresponds to the magnitude of the current flowing from the battery pack 40 to the motor 70.

[0141] The temperature detection circuit 58 detects the circuit temperature of the controller 50 and outputs the detected circuit temperature to the microcomputer 60 .

[0142] The microcomputer 60 includes a CPU 60a and a memory 60b. The memory 60b includes, for example, a semiconductor memory such as a ROM, a RAM, an NVRAM, and a flash memory. The microcomputer 60 implements various functions by executing programs stored in the memory 60b. In addition, the microcomputer 60 stores temporary data generated according to various functions in the memory 60b. In the present embodiment, the microcomputer 60 is equivalent to an example of a control unit of the present invention.

[0143] Part or all of the various functions implemented by the microcomputer 60 may be implemented by executing a program (i.e., by software processing), or may be implemented by one or more hardware. For example, the microcomputer 60 may replace the microcomputer, or in addition to the microcomputer, may also include a logic circuit including multiple electronic components, or may include an integrated circuit for a specific purpose such as an ASIC and / or an ASSP, or may include a programmable logic device such as an FPGA that can construct any logic circuit.

[0144] The microcomputer 60 performs serial communication with the battery pack 40 via the first data communication unit 61, and receives battery information. The battery information includes whether the battery pack 40 is in a state where discharge is possible, or identification data such as the model of the battery pack 40. The microcomputer 60 receives a discharge permission signal or a discharge prohibition signal from the battery pack 40 via the second data communication unit 62. When the battery pack 40 is in a state where discharge is possible, the battery pack 40 transmits a discharge permission signal. When the battery pack 40 is in a state where discharge is not possible, the battery pack 40 transmits a discharge prohibition signal.

[0145] The microcomputer 60 generates a motor control signal and a switch control signal based on the main power signal, the reverse mode signal, the trigger signal, the circuit temperature, the battery voltage value, the battery current value, the position signal, the battery information, the discharge permission signal or the discharge prohibition signal. The microcomputer 60 outputs the generated motor control signal and the switch control signal to the gate circuit 55. The motor control signal is a pulse width modulation (PWM) signal. In addition, the microcomputer 60 controls the LED of the speed display unit 151 based on the main power signal and the reverse mode signal.

[0146] <2. Processing>

[0147] <2-1. Main Process>

[0148] Reference Fig.15 The main process executed by the microcomputer 60 will be described with reference to the flowchart of FIG. The microcomputer 60 repeatedly executes this process in a predetermined control cycle.

[0149] In S10, the microcomputer 60 determines whether a control cycle has passed since the start of this processing cycle. The control cycle is preset. If the microcomputer 60 determines that the control cycle has passed (S10: YES), it proceeds to the processing of S20. If it determines that the control cycle has not passed (S10: NO), it repeatedly executes the processing of S10.

[0150] In S20, the microcomputer 60 performs switch operation detection processing to detect the user's operation on the main power / speed mode switching switch 153, the reverse mode switch 154, and the trigger 14. Then, the microcomputer 60 proceeds to the processing of S30. The switch operation detection processing will be described in detail later.

[0151] In S30, the microcomputer 60 performs AD conversion processing to convert the analog values ​​of the circuit temperature, the battery voltage value, and the battery current value input to the microcomputer 60 into digital values. Then, the microcomputer 60 proceeds to the processing of S40.

[0152] In S40, the microcomputer 60 performs error detection processing. Specifically, the microcomputer 60 detects the occurrence of an error that requires protection of the cleaning device 1 or the battery pack 40 based on the battery current value, the battery voltage value, the circuit temperature, the rotation speed of the motor 70, the battery information, etc. The types of errors include: an overcurrent error in which an excessive current flows through the motor 70, an overload error in which the motor 70 is subjected to an excessive load, a high temperature error in which the circuit temperature is higher than the normal range, a speed exceeding error in which the rotation speed of the motor 70 exceeds the upper limit, and a battery error in which the battery pack 40 is in a discharge prohibited state. Then, the microcomputer 60 enters the processing of S50.

[0153] In S50, the microcomputer 60 executes the motor control process to control the driving of the motor 70. Then, the microcomputer 60 proceeds to the process of S60. The motor control process will be described in detail later.

[0154] In S60, the microcomputer 60 performs display processing. Specifically, the microcomputer 60 turns on, flashes, or turns off the LED of the speed display unit 151 based on the set speed mode and rotation direction. In addition, when the microcomputer 60 detects any error in the processing of S40, the LED of the error display unit 152 is turned on. Then, the microcomputer 60 enters the processing of S70.

[0155] In S70, the microcomputer 60 executes a power management process to turn the main power supply on or off. The power management process will be described in detail later.

[0156] <2-2. Interrupt processing>

[0157] Reference Fig.16The flowchart of FIG. 1 is used to explain the Hall sensor interrupt processing executed by the microcomputer 60. When a position signal is input from any Hall sensor included in the position sensor 65, the microcomputer 60 executes this processing in an interrupt mode.

[0158] In S80, the microcomputer 60 executes the inverter control process to turn on or off the six switching elements of the inverter circuit 56. Then, the microcomputer 60 proceeds to the process of S90. The inverter control process will be described in detail later.

[0159] In S90, the microcomputer 60 performs a calculation process of the rotation angle, and calculates a first rotation angle θ1 and a second rotation angle θ2. The first rotation angle θ1 is an angle at which the front end connection part 30 rotates in the reverse direction. The second rotation angle θ2 is an angle at which the front end connection part 30 rotates in the reverse direction when the front end attachment 20 is pressed against the ground and the front end attachment 20 receives a reaction force from the ground. That is, the second rotation angle θ2 is an angle at which the front end connection part 30 rotates in the reverse direction when the motor 70 receives a load greater than a specified value. Therefore, θ1 ≥ θ2. The calculation process of the rotation angle will be described in detail later.

[0160] <2-1-1. Switch detection processing>

[0161] Reference Fig.17 The switch operation detection process executed by the microcomputer 60 in S20 of the main process will be described with reference to the flowchart of FIG.

[0162] In S100, the microcomputer 60 obtains the states of various switches. That is, the microcomputer 60 obtains the main power signal from the main power / speed mode switching switch 153 and obtains the reverse mode signal from the reverse mode switch 154. In addition, the microcomputer 60 obtains the trigger signal from the trigger 14. Then, the microcomputer 60 enters the process of S110.

[0163] In S110, the microcomputer 60 applies filtering processing to various signals obtained from various switches. Furthermore, when the on state of the signal after filtering processing continues for a certain time or more, the microcomputer 60 detects that the signal is on, and when the off state of the signal after filtering processing continues for a certain time or more, the microcomputer 60 detects that the signal is off. That is, the microcomputer 60 does not detect instantaneous changes in the signal. Then, the microcomputer 60 enters the processing of S120.

[0164] In S120, the microcomputer 60 sets the change flags corresponding to the state changes of various switches to on. Specifically, when the main power signal changes from on to off, or from off to on, the microcomputer 60 sets the main power change flag to on. When the reversal mode signal changes from on to off, or from off to on, the microcomputer 60 sets the reversal mode change flag to on. When the trigger signal changes from on to off, or from off to on, the microcomputer 60 sets the trigger change flag to on. Then, the microcomputer 60 proceeds to the processing of S130.

[0165] In S130, the microcomputer 60 measures the time that various switches are continuously in the on state or the time that various switches are continuously in the off state.

[0166] <2-1-2. Power management processing>

[0167] Reference Fig.18 The power management process executed by the microcomputer 60 in S70 of the main process will be described with reference to the flowchart of FIG.

[0168] In S200, the microcomputer 60 determines whether the current main power state is off. If the microcomputer 60 determines that the current main power state is on (S200: NO), it proceeds to S210, and if the microcomputer determines that the current main power state is off (S200: YES), it proceeds to S220.

[0169] In S210, the microcomputer 60 performs a main power state off determination to determine whether the main power state is switched from on to off or maintained on, and terminates the present process. The main power state off determination will be described in detail later.

[0170] In S220, the microcomputer 60 performs a main power state on determination, determining whether the main power state is switched from off to on or maintained off. Specifically, when the main power change flag is on, the microcomputer 60 switches the main power state from off to on. When the main power change flag is off, the microcomputer 60 maintains the main power state as off. Then, the present process ends.

[0171] <2-1-2A. Main power supply disconnection determination process>

[0172] Reference Fig.19 The main power supply state off determination process executed by the microcomputer 60 in S210 of the power supply management process will be described with reference to the flowchart of FIG.

[0173] In S230, the microcomputer 60 performs: a main power state disconnection determination process based on the switch operation. Specifically, when the main power change flag is on, the microcomputer 60 switches the main power state from on to off. When the main power change flag is off, the microcomputer 60 maintains the main power state as on. Then, the microcomputer 60 proceeds to the process of S240.

[0174] In S240, the microcomputer 60 executes: automatic disconnection determination processing of the main power state. Specifically, even if the main power change flag is off, the microcomputer 60 will determine whether to switch the main power state from on to off in order to save power, and end this processing. The automatic disconnection determination processing of the main power state will be described in detail later.

[0175] <2-1-2Aa. Automatic disconnection determination process>

[0176] Reference Fig. 20 The automatic main power supply state shutoff determination process executed by the microcomputer 60 in S240 of the main power supply state shutoff determination process will be described with reference to the flowchart of FIG.

[0177] In S250, the microcomputer 60 determines whether any switch is operated by the user. That is, the microcomputer 60 determines whether any of the main power change flag, the reverse mode change flag, and the trigger change flag is in the on state. When the microcomputer 60 determines that at least one change flag is in the on state (S250: YES), it proceeds to the processing of S320, and when it determines that all the change flags are in the off state (S250: NO), it proceeds to the processing of S260.

[0178] In S260, the microcomputer 60 increments the main power on timer and proceeds to S270. The main power on timer corresponds to the time during which the main power is on while the user is not operating the cleaning device 1.

[0179] In S270, the microcomputer 60 determines whether the rotation direction of the motor 70 is set to the forward direction. When the microcomputer 60 determines that the rotation direction is set to the forward direction (S270: YES), the microcomputer 60 proceeds to the process of S280. When the microcomputer 60 determines that the rotation direction is set to the reverse direction (S270: NO), the microcomputer 60 proceeds to the process of S300.

[0180] In S280, the microcomputer 60 determines whether the value of the main power supply on timer is a value greater than the first threshold value. The first threshold value is several minutes, for example, 5 minutes. When the user turns on the main power supply, the user sometimes interrupts the operation performed by the cleaning device 1 and performs other operations such as watering. In this case, when the user restarts the operation using the cleaning device 1, if the main power supply is disconnected, the user may feel troubled. On the other hand, in the case where the user forgets to disconnect the main power supply and keeps the cleaning device 1, if the main power supply is not disconnected, the power of the battery pack 40 will be wasted.

[0181] Based on this, the microcomputer 60 determines whether the state in which the user does not operate the cleaning device 1 is an interruption of the operation. If it is determined that it is not an interruption of the operation, the main power supply is turned off. The first threshold is a threshold for determining whether the state in which the cleaning device 1 is not operated is an interruption of the operation. If the microcomputer 60 determines that the value of the main power supply on timer is greater than the first threshold (S280: YES), it enters the process of S290. If it is determined that the value of the main power supply on timer is less than the first threshold (S280: NO), the present process is terminated.

[0182] In S290, the microcomputer 60 determines that the current state is not a work interruption because the user has not operated the cleaning device 1 for a period of time equal to or greater than the first threshold, and sets the main power supply state to OFF. Then, the microcomputer 60 ends the present process.

[0183] In S300, the microcomputer 60 determines whether the value of the main power supply on timer is greater than or equal to the second threshold value. The second threshold value is a value less than the first threshold value, for example, 1 minute. Usually, the user does not reverse the motor 70 except when removing the front end attachment 20. Therefore, when the rotation direction is set to reverse and the user does not operate the cleaning device 1, the microcomputer 60 does not need to determine whether the current state is an interruption of the operation, and only needs to immediately disconnect the main power supply.

[0184] When the microcomputer 60 determines that the value of the main power supply ON timer is equal to or greater than the second threshold value (S300: YES), it proceeds to the process of S310. When it determines that the value of the main power supply ON timer is less than the second threshold value (S300: NO), it ends the process.

[0185] In S310, the microcomputer 60 turns off the main power supply state and ends the present process.

[0186] In S320, the microcomputer 60 clears the main power supply ON timer in response to the user's operation of the cleaning device 1. That is, the microcomputer 60 returns the value of the main power supply ON timer to zero. Then, the microcomputer 60 ends the present process.

[0187] <2-1-3. Motor control processing>

[0188] Reference Fig.21 The motor control process executed by the microcomputer 60 in S50 of the main process will be described with reference to the flowchart of FIG.

[0189] In S400, the microcomputer 60 executes a speed mode setting process and sets the speed mode to any one of the high speed mode, the medium speed mode, and the low speed mode. Then, the microcomputer 60 proceeds to the process of S410. The speed mode setting process will be described in detail later.

[0190] In S410, the microcomputer 60 executes a rotation direction setting process to set the rotation direction of the motor 70. Then, the microcomputer 60 proceeds to a process of S420. The rotation direction setting process will be described in detail later.

[0191] In S420, the microcomputer 60 executes the state transition process to set the control mode of the motor 70 to the drive mode or the stop mode. Then, the microcomputer 60 ends this process. The state transition process will be described in detail later.

[0192] <2-1-3A. Speed ​​mode setting process>

[0193] Reference Fig. 22 The speed mode setting process executed by the microcomputer 60 in S400 of the motor control process will be described with reference to the flowchart of FIG.

[0194] In S430, the microcomputer 60 determines whether the main power state is OFF or ON. When the microcomputer 60 determines that the main power state is ON (S430: YES), the process proceeds to S440. When the microcomputer 60 determines that the main power state is OFF (S430: NO), the process proceeds to S480.

[0195] In S440, the microcomputer 60 determines whether the main power / speed mode switching switch 153 has changed from on to off. That is, the microcomputer 60 determines whether the user has taken his hand off the main power / speed mode switching switch 153. Specifically, the microcomputer 60 determines whether the main power / speed mode switching switch 153 has just been switched from on to off. In S440, the microcomputer 60 determines that the main power / speed mode switching switch 153 has just been switched from on to off (S440: YES), and proceeds to the processing of S450. In S440, the microcomputer 60 determines that the main power / speed mode switching switch 153 has not just been switched from on to off (S440: NO), and ends this processing.

[0196] In S450, the microcomputer 60 determines whether the main power / speed mode switching switch 153 is short pressed. Specifically, the microcomputer 60 determines whether the main power / speed mode switching switch 153 is short pressed based on the duration of the on state of the main power / speed mode switching switch 153 measured in S130. When the microcomputer 60 determines that the main power / speed mode switching switch 153 is short pressed (S450: YES), the microcomputer 60 proceeds to the processing of S460. When it is determined that the main power / speed mode switching switch 153 is not short pressed (S450: NO), the present processing ends.

[0197] In S460, the microcomputer 60 changes the currently set speed mode to the next speed mode, and proceeds to the process of S470.

[0198] In S470, the microcomputer 60 stores the speed pattern changed in S460 in the memory 60b, and ends the present process.

[0199] In S480 , the microcomputer 60 sets the speed mode stored in the memory 60 b as the speed mode for controlling the motor 70 , and ends the present process.

[0200] <2-1-3B. Rotation direction setting process>

[0201] Reference Figures 23A to 23C The flowchart of FIG. 1 will now be described with respect to the rotation direction setting process executed by the microcomputer 60 in S410 of the motor control process.

[0202] First, in the processes of S500 to S560 , the microcomputer 60 executes a process of setting the request for switching the rotation direction of the motor 70 to on or off.

[0203] In S500, the microcomputer 60 determines whether the main power state is on. If the microcomputer 60 determines that the main power state is on (S500: YES), the microcomputer 60 proceeds to the process of S510. If the microcomputer 60 determines that the main power state is off (S500: NO), the microcomputer 60 proceeds to the process of S540.

[0204] In S510, the microcomputer 60 determines whether the reverse mode switch 154 has changed from off to on based on the reverse mode change flag. When the microcomputer 60 determines that the reverse mode switch 154 has changed from off to on (S510: YES), the microcomputer 60 proceeds to the processing of S520. When the microcomputer 60 determines that the reverse mode switch 154 remains off (S510: NO), the microcomputer 60 proceeds to the processing of S570.

[0205] In S520, the microcomputer 60 determines whether a protection action is executed on the cleaning device 1 or the battery pack 40. That is, the microcomputer 60 determines whether any error is detected in S40. When the microcomputer 60 determines that a protection action is executed on the cleaning device 1 or the battery pack 40 (S520: YES), the microcomputer 60 proceeds to the process of S570. When the microcomputer 60 determines that a protection action is not executed on the cleaning device 1 or the battery pack 40 (S520: NO), the microcomputer 60 proceeds to the process of S530.

[0206] In S530 , the microcomputer 60 turns on the request for switching the rotation direction, and proceeds to the process of S570 .

[0207] In S540 , the microcomputer 60 turns off the stop request of the motor 70 based on the fact that the main power supply state is OFF, and proceeds to the process of S550 .

[0208] In S550, the microcomputer 60 sets the rotation direction to the forward direction so as to start the operation in the forward rotation mode when the user uses the cleaning device 1 next time, and proceeds to the process of S560.

[0209] In S560 , the microcomputer 60 turns off the request for switching the rotation direction, and proceeds to the process of S570 .

[0210] Next, in S570 to S610 , the rotation direction switching process is executed based on the rotation direction switching request.

[0211] In S570, the microcomputer 60 determines whether the rotation direction switching request is on. If the microcomputer 60 determines that the rotation direction switching request is on (S570: YES), the microcomputer 60 proceeds to the process of S580. If the microcomputer 60 determines that the rotation direction switching request is off (S570: NO), the microcomputer 60 proceeds to the process of S620.

[0212] In S580, the microcomputer 60 determines whether the rotation speed of the motor 70 is less than the speed threshold. For safety reasons, the microcomputer 60 does not switch the rotation direction during the rotation of the motor 70. In S580, the microcomputer 60 determines whether the motor 70 is in a state that is considered to be stopped. The speed threshold is small enough to be considered to be stopped. If the microcomputer 60 determines that the rotation speed is less than the speed threshold (S580: YES), the microcomputer 60 proceeds to the processing of S590. If the microcomputer 60 determines that the rotation speed is a speed greater than the speed threshold (S580: NO), the microcomputer 60 does not switch the rotation direction and proceeds to the processing of S620.

[0213] In S590, the microcomputer 60 determines whether the trigger 14 is off. If the microcomputer 60 determines that the trigger 14 is off (S590: YES), the microcomputer 60 proceeds to the process of S600. If the microcomputer 60 determines that the trigger 14 is on (S590: NO), the microcomputer 60 proceeds to the process of S620.

[0214] In S600, the microcomputer 60 switches the rotation direction of the motor 70 to a direction different from the currently set rotation direction. That is, when the current rotation direction is set to the forward direction, the microcomputer 60 switches the rotation direction to the reverse direction. When the current rotation direction is set to the reverse direction, the microcomputer 60 switches the rotation direction to the forward direction. Then, the microcomputer 60 proceeds to the processing of S610.

[0215] In S610 , the microcomputer 60 has completed the switching of the rotation direction, and therefore turns off the request for switching the rotation direction, and proceeds to the processing of S620 .

[0216] Next, in S620 to S680 , the microcomputer 60 executes a process of setting the motor stop request to on or off.

[0217] In S620, the microcomputer 60 determines whether the motor stop request is OFF. If the microcomputer 60 determines that the motor stop request is OFF (S620: YES), the microcomputer 60 proceeds to the process of S630. If the microcomputer 60 determines that the motor stop request is ON (S620: NO), the microcomputer 60 proceeds to the process of S660.

[0218] In S630, the microcomputer 60 determines whether the rotation direction switching request is on. If the microcomputer 60 determines that the rotation direction switching request is on (S630: YES), the microcomputer 60 proceeds to the process of S640. If the microcomputer 60 determines that the rotation direction switching request is off (S630: NO), the microcomputer 60 proceeds to the process of S690.

[0219] In S640, the microcomputer 60 determines whether the rotation speed is greater than the speed threshold. If the microcomputer 60 determines that the rotation speed is greater than the speed threshold (S640: YES), the microcomputer 60 proceeds to the process of S650. If the microcomputer 60 determines that the rotation speed is less than the speed threshold (S640: NO), the microcomputer 60 proceeds to the process of S690.

[0220] In S650, the microcomputer 60 turns on the motor stop request. As a result, in the state transition process described later, the motor 70 is stopped so that the rotation speed is less than the speed threshold. Furthermore, in the next control cycle, the rotation direction is switched in S600. Then, the microcomputer 60 proceeds to the process of S690.

[0221] In S660, the microcomputer 60 determines whether the rotation speed is less than the speed threshold. If the microcomputer 60 determines that the rotation speed is less than the speed threshold (S660: YES), the microcomputer 60 proceeds to the processing of S670. If the microcomputer 60 determines that the rotation speed is greater than the speed threshold (S660: NO), the microcomputer 60 proceeds to the processing of S690.

[0222] In S670, the microcomputer 60 determines whether the trigger 14 is off. If the microcomputer 60 determines that the trigger 14 is off (S670: YES), the microcomputer 60 proceeds to the process of S680. If the microcomputer 60 determines that the trigger 14 is on (S670: NO), the microcomputer 60 proceeds to the process of S690.

[0223] In S680 , since the motor 70 is stopped and the user has not requested the motor 70 to be restarted, the microcomputer 60 turns off the motor stop request and proceeds to the process of S690 .

[0224] Next, in S690, the microcomputer 60 executes a process for acquiring the rotation angle of the distal end connection portion 30 to acquire the first rotation angle θ1 and the second rotation angle θ2. Then, the microcomputer 60 proceeds to the process of S700. The process for acquiring the rotation angle of the distal end connection portion 30 will be described in detail later.

[0225] In S700, the microcomputer 60 determines whether the rotation direction is set to reverse. If the microcomputer 60 determines that the rotation direction is set to reverse (S700: YES), the microcomputer 60 proceeds to the process of S710. If the microcomputer 60 determines that the rotation direction is set to forward (S700: NO), the microcomputer 60 ends the process.

[0226] In S710, the microcomputer 60 determines whether the control mode of the motor 70 is set to the drive mode. In the state transition process described later, the control mode is set to the drive mode or the stop mode. When the microcomputer 60 determines that the control mode is set to the drive mode (S710: YES), the microcomputer 60 proceeds to the process of S720. When the microcomputer 60 determines that the control mode is set to the stop mode (S710: NO), the present process ends.

[0227] In S720, the microcomputer 60 determines whether the first rotation angle θ1 acquired in S690 is an angle greater than or equal to the engagement angle Af+α. A is a value of 0 to 360 degrees. Here, the microcomputer 60 does not determine whether the front attachment 20 is detached from the cleaning device 1. However, when the front attachment 20 is pressed against the floor, if the front connection part 30 is rotated in the reverse direction by an angle greater than or equal to the engagement angle Af+α, the front attachment 20 is detached from the cleaning device 1. The microcomputer 60 stops the motor 70 because a malfunction may occur if the front connection part 30 continues to reverse. In S720, the microcomputer 60 determines whether the rotation state of the front connection part 30 is a state in which the motor 70 should be stopped. When the microcomputer 60 determines that the first rotation angle θ1 is an angle greater than or equal to the engagement angle Af+α (S720: YES), the microcomputer 60 proceeds to the processing of S730. When the microcomputer 60 determines that the first rotation angle θ1 is smaller than the engagement angle Af+α ( S720 : NO), the present process ends.

[0228] In S730 , the microcomputer 60 turns on the motor stop request and proceeds to the process of S740 .

[0229] In S740, the microcomputer 60 performs an automatic recovery determination process toward forward rotation. Specifically, the microcomputer 60 determines whether the front attachment 20 has been separated from the cleaning device 1. When the microcomputer 60 determines that the front attachment 20 has been separated from the cleaning device 1, the microcomputer 60 automatically changes the rotation direction to forward rotation without the user operating the reverse mode switch 154. The automatic recovery determination process toward forward rotation will be described in detail later. Then, the microcomputer 60 ends this process.

[0230] <2-1-3Ba. Processing of obtaining the rotation angle of the connection portion>

[0231] Reference Fig.24 A first example of the process of acquiring the rotation angle of the connection portion executed by the microcomputer 60 in S690 of the process of setting the rotation direction will be described with reference to the flowchart of FIG.

[0232] In S800, the microcomputer 60 determines whether the rotation direction is set to the reverse direction. If the microcomputer 60 determines that the rotation direction is set to the reverse direction (S800: YES), the microcomputer 60 proceeds to the process of S810. If the microcomputer 60 determines that the rotation direction is set to the forward direction (S800: NO), the microcomputer 60 proceeds to the process of S830.

[0233] In S810, the microcomputer 60 turns on the acquisition request of the first rotation angle θ1. As a result, the first rotation angle θ1 is calculated in the rotation angle calculation process described later. Then, the microcomputer 60 proceeds to the process of S820.

[0234] In S820 , the microcomputer 60 acquires the first rotation angle θ1 calculated in the rotation angle calculation process, and proceeds to the process of S850 .

[0235] In S830 , the microcomputer 60 turns off the acquisition request of the first rotation angle θ1 and proceeds to the process of S840 .

[0236] In S840 , the microcomputer 60 sets the first rotation angle θ1 to 0 degrees, and proceeds to the process of S880 .

[0237] In S850, the microcomputer 60 determines whether the motor load is greater than the load threshold. The motor load is the load borne by the motor 70. When the front attachment 20 is pressed against the ground, the front attachment 20 receives a reaction force from the ground, and the motor 70 receives the load through the front attachment 20.

[0238] The motor load corresponds to the rotation speed, the battery current value, or the motor current value. Therefore, the microcomputer 60 can determine whether the motor load is above the load threshold value based on the rotation speed, the battery current value, or the motor current value. The motor current value corresponds to the magnitude of the current flowing through the motor 70 and is estimated by the motor current value = battery current value ÷ output duty ratio × 100. The output duty ratio is: the duty ratio of the PWM signal output by the microcomputer 60 to the gate circuit 55.

[0239] When the microcomputer 60 performs the determination of S850 based on the battery current value or the motor current value, the load threshold is set to, for example, 10A. When the microcomputer 60 performs the determination of S850 based on the rotation speed, the motor load is set to the difference between the expected rotation speed and the actual rotation speed, and the load threshold is set to, for example, 1000 rpm. The expected rotation speed is the rotation speed corresponding to the applied voltage value when the motor 70 is not subjected to the load. The applied voltage value corresponds to the magnitude of the voltage applied to the winding of the motor 70, and is estimated by the applied voltage value = the output voltage value of the battery pack 40 × the output duty ratio ÷ 100. For example, when the applied voltage value is 32V, the expected rotation speed is 20000 rpm. When the expected rotation speed is 2000 rpm and the actual rotation speed is 18000 rpm, the microcomputer 60 determines that the motor load is greater than the load threshold. In addition, when the motor 70 is controlled to rotate at a constant speed, when the motor load increases, the rotation speed is maintained, but the applied voltage value increases. For example, when the applied voltage value for maintaining a rotation speed of 2000 rpm is 36V, and the rotation speed is 22500 rpm when a voltage of 36V is applied to the motor 70 without a load, the microcomputer 60 determines that the motor load is above the load threshold.

[0240] When the microcomputer 60 determines that the motor load is equal to or greater than the load threshold (S850: YES), the microcomputer 60 proceeds to the process of S860. When the microcomputer 60 determines that the motor load is less than the load threshold (S850: NO), the microcomputer 60 proceeds to the process of S880.

[0241] In S860, the microcomputer 60 turns on the acquisition request of the second rotation angle θ2. Thus, the second rotation angle θ2 is calculated in the rotation angle calculation process. Then, the microcomputer 60 proceeds to the process of S870.

[0242] In S870 , the microcomputer 60 acquires the second rotation angle θ2 calculated in the rotation angle calculation process, and ends this process.

[0243] In S880 , the microcomputer 60 turns off the acquisition request for the second rotation angle θ2 and proceeds to the process of S890 .

[0244] In S890, the microcomputer 60 sets the second rotation angle θ2 to 0 degrees, and ends the present process.

[0245] Next, refer to Fig.25 , a second example of the processing for obtaining the rotation angle of the connection portion executed by the microcomputer 60 in S690 of the rotation direction setting processing is described. In the second example, it is assumed that the motor 70 is a brush motor. When the motor 70 is a brush motor, the microcomputer 60 does not execute the processing for calculating the rotation angle in S90 of the Hall sensor interrupt processing.

[0246] In S105, the microcomputer 60 determines whether the rotation direction is set to the reverse direction. If the microcomputer 60 determines that the rotation direction is set to the reverse direction (S105: YES), the microcomputer 60 proceeds to the process of S115. If the microcomputer 60 determines that the rotation direction is set to the forward direction (S105: NO), the microcomputer 60 proceeds to the process of S175.

[0247] In S115, the microcomputer 60 calculates or estimates the rotation speed of the motor 70. Specifically, the microcomputer 60 calculates or estimates the rotation speed of the motor 70 based on the applied voltage value and the output duty ratio. Then, the microcomputer 60 proceeds to the process of S125.

[0248] In S125, the microcomputer 60 calculates or estimates the rotation speed of the front end connection part 30 based on the rotation speed of the motor 70 estimated or calculated in S115. Specifically, the microcomputer 60 calculates or estimates the rotation speed of the front end connection part 30 based on the rotation speed of the motor 70 and the gear ratio of the speed reduction mechanism 75. Then, the microcomputer 60 proceeds to the process of S135.

[0249] In S135, the microcomputer 60 calculates the first displacement angle Δθ1 based on the rotation speed of the front end connection part 30. The first displacement angle Δθ1 corresponds to the rotation angle of the front end connection part 30 in each control cycle. For example, when the rotation speed of the front end connection part 30 is 300 rpm and the control cycle is 1 ms, the first displacement angle Δθ1 = 360 degrees × 300 ÷ 60000 = 1.8 degrees. Then, the microcomputer 60 enters the process of S135.

[0250] In S145, the microcomputer 60 adds the first shift angle Δθ1 to the first rotation angle θ1, and proceeds to the process of S155.

[0251] In S155, the microcomputer 60 determines whether the motor load is greater than the load threshold value, similar to the process of S850. When the microcomputer 60 determines that the motor load is greater than the load threshold value (S155: YES), the microcomputer 60 proceeds to the process of S165. When the microcomputer 60 determines that the motor load is less than the load threshold value (S155: NO), the microcomputer 60 proceeds to the process of S185.

[0252] In S165, the microcomputer 60 adds the first shift angle Δθ1 to the second rotation angle θ2, and ends the present process.

[0253] In S175 , the microcomputer 60 sets the first rotation angle θ1 to 0 degrees, and proceeds to the process of S185 .

[0254] In S185, the microcomputer 60 sets the second rotation angle θ2 to 0 degrees, and ends the present process.

[0255] <2-1-3Bb. Automatic recovery determination process for forward rotation>

[0256] Reference Fig.26 A first example of the automatic return determination process toward forward rotation executed by the microcomputer 60 in S740 of the rotation direction setting process will be described with reference to the flowchart of FIG.

[0257] In S205, the microcomputer 60 executes an automatic recovery determination process based on the second rotation angle θ2, and terminates the present process. The automatic recovery determination process based on the second rotation angle θ2 will be described in detail later.

[0258] Next, refer to Fig. 27 A second example of the automatic return determination process toward forward rotation executed by the microcomputer 60 in S740 of the rotation direction setting process will be described with reference to the flowchart of FIG.

[0259] In S215, the microcomputer 60 executes an automatic recovery determination process based on the number of times the drive is performed during reverse rotation, and terminates the present process. The automatic recovery determination process based on the number of times the drive is performed during reverse rotation will be described in detail later.

[0260] Next, refer to Fig.28 A third example of the automatic return determination process toward forward rotation executed by the microcomputer 60 in S740 of the rotation direction setting process will be described with reference to the flowchart of FIG.

[0261] In S225 , the microcomputer 60 executes the automatic recovery determination process based on the second rotation angle θ2 in the same manner as in S205 , and proceeds to the process of S235 .

[0262] In S235, the microcomputer 60 executes the automatic recovery determination process based on the number of driving times during reverse rotation similarly to S215, and ends this process. That is, in the third example, the microcomputer 60 executes both the determination process of the first example and the determination process of the second example.

[0263] <2-1-3Bba. Automatic recovery determination process based on the second rotation angle>

[0264] Next, refer to Fig.29 The automatic recovery determination process based on the second rotation angle executed by the microcomputer 60 in S205 or S225 of the automatic recovery determination process toward the forward rotation will be described with reference to the flowchart of FIG.

[0265] In S245, the microcomputer 60 determines whether the second rotation angle θ2 is an angle greater than or equal to the engagement angle Af+β. β≤α. Here, the microcomputer 60 determines whether the front end attachment 20 has been separated from the front end connection part 30. When the front end attachment 20 is pressed against the ground, if the front end connection part 30 is reversed by an angle greater than or equal to the engagement angle Af+β, the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25 is released, and it can be estimated that the front end attachment 20 has been separated from the front end connection part 30. When the microcomputer 60 determines that the second rotation angle θ2 is an angle greater than or equal to the engagement angle Af+β (S245: YES), the microcomputer 60 proceeds to the processing of S255. When the microcomputer 60 determines that the second rotation angle θ2 is smaller than the engagement angle Af+β (S245: NO), the present processing ends.

[0266] In S255, the microcomputer 60 can infer that the front attachment 20 has been separated from the front connection portion 30, and therefore the rotation direction is returned to the forward direction, and thus turns on the rotation direction switching request. Then, the microcomputer 60 ends the present process.

[0267] <2-1-3Bbb. Automatic recovery determination process based on the number of times of driving during reverse rotation>

[0268] Next, refer to Fig.30 The automatic recovery determination process based on the number of driving times in reverse rotation, which is executed by the microcomputer 60 in S215 or S235 of the automatic recovery determination process toward forward rotation, is described with reference to the flowchart of FIG. 1. One driving time corresponds to: from the start of rotation of the motor 70 to the stop.

[0269] In S265, the microcomputer 60 determines whether the rotation direction has been set to forward rotation in the previous drive of the motor 70. When the microcomputer 60 determines that the rotation direction has been set to forward rotation (S265: YES), the microcomputer 60 proceeds to the process of S275. When the microcomputer 60 determines that the rotation direction has been set to reverse rotation (S265: NO), the microcomputer 60 proceeds to the process of S285.

[0270] In S275, the microcomputer 60 sets the number of driving times in reverse rotation to 1, and proceeds to the process of S295.

[0271] In S285, the microcomputer 60 adds "1" to the number of driving times in reverse rotation, and proceeds to the process of S295.

[0272] In S295, the microcomputer 60 determines whether the number of times of driving in reverse rotation is equal to or greater than a predetermined number of times. Here, the microcomputer 60 determines whether the front attachment 20 has been separated from the front connection part 30. When the number of times of driving in reverse rotation has reached the predetermined number of times while the front attachment 20 is pressed against the ground, the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25 is released, and it can be estimated that the front attachment 20 has been separated from the front connection part 30. One driving corresponds to the period from the start of rotation of the motor 70 to the stop. The rotation speed of the motor 70×the control cycle×the predetermined number of times corresponds to the engagement angle Af+β. When the microcomputer 60 determines that the number of times of driving in reverse rotation is equal to or greater than the predetermined number of times (S295: YES), the microcomputer 60 proceeds to the process of S305. When the microcomputer 60 determines that the number of times of driving in reverse rotation is less than the predetermined number of times (S295: NO), the present process is terminated.

[0273] In S305, the microcomputer 60 turns on the request for switching the rotation direction so as to return the rotation direction to the forward direction. Then, the present process ends.

[0274] <2-1-3C. State transition processing>

[0275] Reference Fig.31 The state transition process executed by the microcomputer 60 in S420 of the motor control process will be described with reference to the flowchart of FIG.

[0276] In S405, the microcomputer 60 determines whether the main power state is on. If the microcomputer 60 determines that the main power state is on (S405: YES), the microcomputer 60 proceeds to the process of S415. If the microcomputer 60 determines that the main power state is off (S405: NO), the microcomputer 60 proceeds to the process of S475.

[0277] In S415, the microcomputer 60 determines whether the protection operation of the cleaning device 1 or the battery pack 40 is executed. When the microcomputer 60 determines that the protection operation of the cleaning device 1 or the battery pack 40 is executed (S415: YES), the microcomputer 60 proceeds to the processing of S475. When the microcomputer 60 determines that the protection operation of the cleaning device 1 or the battery pack 40 is not executed (S415: NO), the microcomputer 60 proceeds to the processing of S425.

[0278] In S425, the microcomputer 60 determines whether the trigger 14 is on. If the microcomputer 60 determines that the trigger 14 is on (S425: YES), the microcomputer 60 proceeds to the process of S435. If the microcomputer 60 determines that the trigger 14 is off (S425: NO), the microcomputer 60 proceeds to the process of S475.

[0279] In S435, the microcomputer 60 determines whether the motor stop request is OFF. If the microcomputer 60 determines that the motor stop request is OFF (S435: YES), the microcomputer 60 proceeds to the process of S445. If the microcomputer 60 determines that the motor stop request is ON (S435: NO), the microcomputer 60 proceeds to the process of S475.

[0280] In S445 , the microcomputer 60 sets the control mode of the motor 70 to the drive mode, and proceeds to the process of S455 .

[0281] In S455, the microcomputer 60 sets the target rotation speed corresponding to the set speed mode based on the fact that the control mode is the drive mode. Fig.34 As shown in FIG. 6 , the target rotation speed for each speed mode is stored in the preset memory 60 b. Then, the microcomputer 60 proceeds to the process of S465 .

[0282] In S465, the microcomputer 60 calculates the output duty ratio of the PWM signal based on the target rotation speed set in S455. Specifically, the microcomputer 60 calculates the output duty ratio based on the speed difference between the target rotation speed and the actual rotation speed through proportional-integral control. Then, the microcomputer 60 ends this process.

[0283] In S475 , the microcomputer 60 sets the control mode of the motor 70 to the stop mode, and proceeds to the process of S485 .

[0284] In S485 , the microcomputer 60 executes a stop process of the motor 70 based on the fact that the control mode is the stop mode, and proceeds to the process of S495 .

[0285] In S495, the microcomputer 60 initializes the output duty ratio and ends the present process.

[0286] <2-2-1. Calculation of rotation angle>

[0287] Reference Fig.32 The calculation process of the rotation angle executed by the microcomputer 60 in S90 of the Hall sensor interrupt process will be described with reference to the flowchart of FIG.

[0288] In S900, the microcomputer 60 determines whether the acquisition request of the first rotation angle θ1 is on. When the microcomputer 60 determines that the acquisition request of the first rotation angle θ1 is on (S900: YES), the microcomputer 60 proceeds to the process of S910. When the acquisition request of the first rotation angle θ1 is off (S900: NO), the microcomputer 60 proceeds to the process of S940.

[0289] In S910, the microcomputer 60 determines whether the position signal output from the position sensor 65 meets expectations. Specifically, the microcomputer 60 determines whether the position signals are output from the three Hall sensors in the expected order based on the rotation direction of the motor 70. When the microcomputer 60 determines that the position signal meets expectations (S910: YES), the microcomputer 60 proceeds to the processing of S920. When the microcomputer 60 determines that the position signal does not meet expectations (S910: NO), the microcomputer 60 proceeds to the processing of S930.

[0290] In S920, the microcomputer 60 adds the second displacement angle Δθ2 to the first rotation angle θ1. The second displacement angle Δθ2 corresponds to the angle at which the front end connection part 30 rotates between the output of two consecutive position signals. For example, when the motor 70 is a 4-pole motor, a mechanical angle of 360 degrees corresponds to an electrical angle of 360 degrees × 2. In addition, when the gear ratio of the speed reduction mechanism 75 is 20, one rotation of the front end connection part 30 corresponds to 20 rotations of the rotor. In this case, the second displacement angle Δθ2 corresponds to an electrical angle of 60 degrees (that is, between the outputs of the position signals), so that while the front end connection part 30 is displaced by the second displacement angle θ2, the motor is displaced by 30 degrees in units of mechanical angle. When the motor is displaced by 30 degrees, the front end connection part 30 is displaced by 30 degrees ÷ 20 (gear ratio) = 1.5 degrees. Therefore, the second displacement angle Δθ2 is 1.5 degrees. Then, the microcomputer 60 proceeds to the process of S940.

[0291] In S930, the microcomputer 60 subtracts the second displacement angle Δθ2 from the first rotation angle θ1. If the position signal does not meet expectations, it can be considered that the rotor rotates in the opposite direction. Based on this, the microcomputer 60 subtracts the second displacement angle Δθ2 from the first rotation angle θ1. Then, the microcomputer 60 proceeds to the processing of S940.

[0292] In S940, the microcomputer 60 determines whether the acquisition request of the second rotation angle θ2 is on. When the microcomputer 60 determines that the acquisition request of the second rotation angle θ2 is on (S940: YES), the microcomputer 60 proceeds to the process of S950. When the microcomputer 60 determines that the acquisition request of the second rotation angle θ2 is off (S940: NO), the present process ends.

[0293] In S950, the microcomputer 60 determines whether the position signal output from the position sensor 65 meets expectations. If the microcomputer 60 determines that the position signal meets expectations (S950: YES), the microcomputer 60 proceeds to the process of S960. If the microcomputer 60 determines that the position signal does not meet expectations (S960: NO), the microcomputer 60 proceeds to the process of S970.

[0294] In S960 , the microcomputer 60 adds the second shift angle Δθ2 to the second rotation angle θ2 and ends the present process.

[0295] In S970 , the microcomputer 60 subtracts the second shift angle Δθ2 from the second rotation angle θ2 and ends the present process.

[0296] <2-2-2. Inverter control processing>

[0297] Reference Fig.33 The inverter control process executed by the microcomputer 60 in S80 of the Hall sensor interrupt process will be described with reference to the flowchart of FIG.

[0298] In S505 , the microcomputer 60 acquires the set control mode and proceeds to the process of S515 .

[0299] In S515 , the microcomputer 60 acquires the set rotation direction and proceeds to the process of S525 .

[0300] In S525 , the microcomputer 60 acquires the calculated output duty ratio, and proceeds to the process of S535 .

[0301] In S535 , the microcomputer 60 acquires the position of the rotor based on the position signal output from the position sensor 65 , and proceeds to the process of S545 .

[0302] In S545, the microcomputer 60 controls the inverter circuit 56 via the gate circuit 55, thereby driving the motor 70. Specifically, the microcomputer 60 generates a PWM signal based on the acquired control mode, rotation direction, output duty ratio, and position signal, and outputs the PWM signal to the gate circuit 55. Then, the microcomputer 60 ends the present process.

[0303] <3. Effect>

[0304] According to the first embodiment described in detail above, the following effects can be achieved.

[0305] (1) The microcomputer 60 stops the motor 70 when the first rotation angle θ1 becomes equal to or larger than the engagement angle Af+α. Therefore, it is possible to prevent the user from using the cleaning device 1 without noticing that the motor 70 is rotating.

[0306] (2) The microcomputer 60 stops the motor 70 and returns the rotation direction to the forward direction based on the fact that the second rotation angle θ2 becomes equal to or greater than the engagement angle Af+β. Thus, the front end attachment 20 can be more reliably detached from the front end connection portion 30, and when the user uses the cleaning device 1 again, the user can use the cleaning device 1 without paying attention to the rotation direction of the motor 70.

[0307] (3) The microcomputer 60 stops the motor 70 and returns the rotation direction to the forward direction when the number of times the motor 70 is driven in the reverse direction is greater than a predetermined number of times. Thus, the front end connection part 30 and the front end attachment 20 can be more appropriately detached from the front end connection part 30, and the user can use the cleaning device 1 without paying attention to the rotation direction of the motor 70 when using the cleaning device 1 next time.

[0308] (Second embodiment)

[0309] <1. Differences from the first embodiment>

[0310] The basic structure of the second embodiment is the same as that of the first embodiment, so the differences will be described below. In addition, the same reference numerals as those of the first embodiment represent the same structure, and the previous description is referred to.

[0311] The second embodiment differs from the first embodiment in the rotation direction setting process and the state transition process. The rotation direction setting process of the second embodiment differs from the first embodiment in that a pressing determination is added to determine whether the front attachment 20 is pressed against the ground.

[0312] <2. Processing>

[0313] <2-1. Rotation direction setting process>

[0314] Reference Fig.35 Flow chart of microcomputer 60 replaces Fig.23C The third part of the setting process of the rotation direction shown in FIG. 1 is described below. Fig.23A as well as Fig. 23B After completing the first and second parts of the rotation direction setting process shown in the flowchart of Fig.35 Part 3 of the rotation direction setting process is shown in the flowchart.

[0315] In S605, the microcomputer 60 executes the same processing as S690, and proceeds to the processing of S615.

[0316] In S615, the microcomputer 60 performs a push determination process. That is, the microcomputer 6 acquires a first signal indicating whether the front end attachment 20 is pressed against the ground, and determines whether the front end attachment 20 is pushed toward the ground based on the acquired first signal. Then, the microcomputer 60 proceeds to the process of S625. The push determination process will be described in detail later.

[0317] In S625, the microcomputer 60 checks the result of the push determination process. When the microcomputer 60 sets the result of the determination to "yes", the process proceeds to S635. When the microcomputer 60 sets the result of the determination to "no", the process proceeds to S685. When the microcomputer 60 sets the result of the determination to "not completed", the present process ends.

[0318] In S635 to S675, the microcomputer 60 executes the same processing as S700 to S740, and ends the present processing.

[0319] In S685, based on the fact that the acquired first signal indicates that the front attachment 20 is not pressed against the ground, the microcomputer 60 turns on the motor stop request, thereby immediately stopping the motor 70. Then, the microcomputer 60 ends the present process.

[0320] <2-1-1. Push determination processing>

[0321] Reference Fig.36 , a first example of the push determination process executed by the microcomputer 60 in S615 of the rotation direction setting process will be described. In the first example, the push determination process is executed based on the rotation state of the front end connection part 30.

[0322] Here, in the state transition process described later, when the rotation direction is set to the reverse direction and the push determination is not completed, the output duty ratio is calculated in such a manner that the first voltage of the predetermined voltage value is applied to the motor 70. Furthermore, based on the fact that the push determination is completed, the output duty ratio is calculated in such a manner that the first voltage of the applied voltage value corresponding to the target rotation speed is applied to the motor 70.

[0323] The predetermined voltage value is smaller than: the applied voltage value corresponding to the target rotation speed. The predetermined voltage value is: a very small voltage value for performing the push judgment. Specifically, when the first voltage is applied to the motor 70, (i) the motor 70 and the front end connection part 30 are not rotated corresponding to the front end attachment 20 being pushed against the ground, and (ii) the motor 70 and the front end connection part 30 are rotated corresponding to the front end attachment 20 not being pushed against the ground. That is, when the first voltage is applied to the motor 70, (i) the torque of the motor 70 is smaller than the external force (that is, the reaction force from the ground) corresponding to the front end attachment 20 being pressed against the ground, and (ii) the torque of the motor 70 is larger than the external force corresponding to the front end attachment 20 not being pushed against the ground.

[0324] In S705, the microcomputer 60 determines whether the control mode of the motor 70 is set to the drive mode. When the microcomputer 60 determines that the control mode is set to the drive mode (S705: YES), the microcomputer 60 proceeds to the process of S715. When the microcomputer 60 determines that the control mode is not set to the drive mode (S705: NO), the microcomputer 60 proceeds to the process of S775.

[0325] In S715, the microcomputer 60 determines whether the mask time has passed since the start of the drive of the motor 70. The mask time is the time required for the drive force of the motor 70 to be transmitted to the front end connection part 30 via the speed reduction mechanism 75. The mask time is a very short time, for example, 0.05 seconds. When the microcomputer 60 determines that the mask time has passed (S715: YES), the microcomputer 60 proceeds to the process of S725. When the microcomputer 60 determines that the mask time has not passed (S715: NO), the microcomputer 60 proceeds to the process of S775.

[0326] In S725, the microcomputer 60 determines whether the result of the push determination is set to "not completed". If the microcomputer 60 determines that the result of the push determination is set to "not completed", the microcomputer 60 proceeds to the process of S735. If the microcomputer 60 determines that the result of the determination is set to "yes" or "no", the microcomputer 60 ends the present process.

[0327] In S735, the microcomputer 60 determines whether a predetermined time has passed since the start of the drive of the motor 70. The predetermined time is longer than the masking time, and corresponds to a time for confirming that the motor 70 does not rotate even if the motor 70 is driven for a period of time. If the microcomputer 60 determines that the predetermined time has passed (S735: YES), the microcomputer 60 proceeds to the process of S745. If the microcomputer 60 determines that the predetermined time has not passed (S735: NO), the microcomputer 60 proceeds to the process of S755.

[0328] In S745, the microcomputer 60 sets the determination result to "yes", and proceeds to the process of S755.

[0329] In S755, the microcomputer 60 determines whether the first rotation angle θ1 is an angle greater than the angle threshold. The angle threshold may be a very small value that can determine whether the front end connection portion 30 has moved. For example, the angle threshold is 3 degrees. When the microcomputer 60 determines that the first rotation angle θ1 is an angle greater than the angle threshold (S755: YES), the microcomputer 60 proceeds to the process of S765. When the microcomputer 60 determines that the first rotation angle θ1 is less than the angle threshold (S755: NO), the present process ends.

[0330] In S765, the microcomputer 60 sets the determination result to "no", and ends the present process.

[0331] In S775, the microcomputer 60 sets the determination result to "not completed" and ends the present processing.

[0332] Reference Fig.37 The flowchart of FIG. 6 illustrates a second example of the push determination process executed by the microcomputer 60 in S615 of the rotation direction setting process. In the second example, the push determination process is executed based on the battery current value. The battery current is generated according to the voltage difference between the applied voltage value and the induced voltage value. The induced voltage value corresponds to the magnitude of the voltage induced in the winding by the rotation of the motor 70, and corresponds to the rotation speed of the motor 70. Therefore, when the front end attachment 20 is pushed against the ground, the battery current value increases in accordance with the increase in the voltage difference. When the front end attachment 20 is not pushed against the ground, the battery current value decreases in accordance with the decrease in the voltage difference.

[0333] In S805 to S825, the microcomputer 60 executes the same processing as S705 to S725, and proceeds to the processing of S835, or proceeds to the processing of S865, or ends the present processing.

[0334] In S835, the microcomputer 60 determines whether the battery current value is a current greater than the current threshold value. The current threshold value may be a very small value that can determine whether the front end connection portion 30 is active. For example, the current threshold value is 1A. When the microcomputer 60 determines that the battery current value is greater than the current threshold value (S835: YES), the microcomputer 60 proceeds to the process of S845. When the microcomputer 60 determines that the battery current value is less than the current threshold value (S835: NO), the microcomputer 60 proceeds to the process of S855.

[0335] In S845, the microcomputer 60 sets the determination result to "yes", and ends the present process.

[0336] In S855, the microcomputer 60 sets the determination result to "no", and ends the present process.

[0337] In S865, the microcomputer 60 sets the determination result to "not completed", and ends the present process.

[0338] <2-2. State transition processing>

[0339] Reference Fig.38 Flow chart of microcomputer 60 replaces Fig.31 The state transition processing performed by the state transition processing shown in FIG.

[0340] In S905 to S945, the microcomputer 60 executes the same processing as S405 to S445, and proceeds to the processing of S948 or S995.

[0341] In S948, the microcomputer 60 determines whether the rotation direction is set to the reverse direction. If the microcomputer 60 determines that the rotation direction is set to the reverse direction (S948: YES), the microcomputer 60 proceeds to the process of S955. If the microcomputer 60 determines that the rotation direction is set to the forward direction (S948: NO), the microcomputer 60 proceeds to the process of S975.

[0342] In S955, the microcomputer 60 determines whether the judgment result of the push judgment is set to "not completed". When it is determined that the judgment result is set to "not completed" (S955: YES), the microcomputer 60 proceeds to the processing of S965. When it is determined that the judgment result of the push judgment is set to "yes" or "no" (S955: NO), the microcomputer 60 proceeds to the processing of S975.

[0343] In S965 , the microcomputer 60 calculates the output duty ratio so that the applied voltage value of the motor 70 becomes a predetermined voltage value.

[0344] In S975 and S985, the microcomputer 60 performs the same processing as S455 and S465. The microcomputer 60 applies the second voltage to the motor 70 based on the first signal indicating that the front end attachment 20 is pressed against the ground. The second voltage has a voltage value greater than a predetermined voltage value. Specifically, the microcomputer 60 gradually increases the output duty ratio. Then, the microcomputer 60 ends this processing.

[0345] In S995 to S1015, the microcomputer 60 executes the same processing as S475 to S495, and ends the present processing.

[0346] exist Fig.39 40 shows the result after the microcomputer 60 executes the state transition process. Fig.39 As shown, when the front end attachment 20 is pressed against the ground, the output duty ratio is constant during the period from time t0 to time t1, and the first rotation angle θ1 is 0 degrees. Time t0 is the time when the drive of the motor 70 is started. Time t1 is the time when the push judgment is completed. During the period from time t0 to time t1, the output duty ratio corresponds to the value calculated by applying the first voltage to the motor 70. From time t1, the output duty ratio and the first rotation angle θ1 gradually increase. Moreover, at time t2, based on the fact that the first rotation angle θ1 becomes an angle greater than the engagement angle Af+α, the rotation of the motor 70 is automatically stopped.

[0347] In addition, if Fig.40 As shown in FIG. 1 , when the front end attachment 20 is not pressed against the ground, the motor 70 rotates, so the first rotation angle θ1 gradually increases from time t10. Time t10 is the time when the motor 70 starts driving. And at time t11, the rotation of the motor 70 is automatically stopped based on the fact that the first rotation angle θ1 becomes an angle greater than the engagement angle Af+α.

[0348] <3. Effect>

[0349] According to the second embodiment described in detail above, it is possible to achieve the effects (1) to (3) of the first embodiment described above, and further, the following effects can be achieved.

[0350] (4) When the front attachment 20 is pressed against the ground and the motor 70 is subjected to a load from the ground, the motor 70 rotates in the reverse direction, thereby detaching the front attachment 20 from the front connection portion 30. In a case where the front attachment 20 is not pressed against the ground even though the rotation direction has been switched to the reverse direction, the user may mistakenly believe that the rotation direction has been switched to the forward direction and start working with the cleaning device 1. When it is determined that (i) the rotation direction has been switched to the reverse direction and (ii) the front attachment 20 is not pressed against the ground, the microcomputer 60 immediately stops the motor 70, thereby more appropriately preventing the user from using the cleaning device 1 while the motor 70 is rotating in the reverse direction.

[0351] (5) In the cleaning device 1, during the judgment process of pushing, the voltage applied to the motor 70 is suppressed, so that the torque of the motor 70 is suppressed to the extent that the motor 70 cannot rotate despite the load received from the ground. Furthermore, when it is determined that the front attachment is pressed against the ground, the voltage applied to the motor 70 is increased, so that the torque of the motor is increased so that the motor can rotate despite the load received from the ground. Therefore, the user can safely remove the front attachment 20 from the front connection portion 30.

[0352] (6) The microcomputer 60 can obtain the first signal indicating whether the front attachment 20 is pressed against the ground based on the rotation state of the motor 70 .

[0353] (Other embodiments)

[0354] As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, Various deformation|transformation can be made and it can be implemented.

[0355] (a) In the above-mentioned embodiments, the microcomputer 60 determines whether the first rotation angle θ1 is an angle greater than or equal to the engagement angle Af+α in the processing of S720 and S655. However, instead of this determination, it is possible to determine whether the front end connection part 30 has rotated in the reverse direction for a first time. The first time is a time corresponding to the rotation speed and the engagement angle Af, and is calculated based on (engagement angle Af+α) / rotation speed of the front end connection part 30. In addition, in the processing of S245, the microcomputer 60 determines whether the second rotation angle θ2 is an angle greater than or equal to the engagement angle Af+β. However, instead of this determination, it is possible to determine whether the front end connection part 30 has rotated in the reverse direction for a second time when the motor 70 is subjected to a load greater than a load threshold. The second time is a time corresponding to the rotation speed and the engagement angle Af, and is calculated based on (engagement angle Af+β) / rotation speed of the front end connection part 30.

[0356] (b) In the processes of S720 and S245 of the first embodiment and S655 of the second embodiment, the microcomputer 60 uses the engagement angle Af to perform the determination. However, the determination may be performed using the overlap angle A4 instead of the engagement angle Af. The overlap angle A4 is larger than the engagement angle Af, so the front end attachment 20 can be more appropriately removed from the front end connection part 30. Alternatively, the microcomputer 60 may determine in the processes of S720 and S655 whether the front end connection part 30 has rotated in the reverse direction for a third time. The third time is a time corresponding to the rotation speed and the overlap angle A4, and is calculated based on (overlap angle A4+α) / rotation speed of the front end connection part 30. In addition, the microcomputer 60 may determine in the process of S245 whether the front end connection part 30 has rotated in the reverse direction for a fourth time. The fourth time is a time corresponding to the rotation speed and the overlap angle A4, and is calculated based on (overlap angle A4+β) / rotation speed of the front end connecting portion 30.

[0357] (c) In the second embodiment, the output duty ratio is reduced during the push determination process to suppress the voltage applied to the motor 70, and after the push determination is completed, the output duty ratio is gradually increased to increase the voltage applied to the motor 70, but the present invention is not limited thereto. As long as the motor 70 is controlled to rotate at a constant speed, the motor 70 is controlled to have a first rotation speed during the push determination process, and after the push determination is completed, the motor 70 is controlled to have a second rotation speed higher than the first rotation speed.

[0358] (d) In each of the above embodiments, the cleaning device 1 is a handheld device. However, the cleaning device 1 is not limited to the handheld type, and may be a hand-pushed device having at least one wheel.

[0359] (e) In the above embodiments, the cleaning device 1 includes the battery mounting unit 41, but may include a power cord instead of or in addition to the battery mounting unit 41. That is, the cleaning device 1 may connect the power cord to an external power source such as a commercial power source to receive power from the external power source.

[0360] (f) In the above-mentioned embodiments, the cleaning device 1 includes three first claws, but may include two or four or more first claws. The front attachment 20 includes three second claws, but may include two or four or more second claws.

Claims

1. A cleaning device capable of being equipped with a front end attachment, characterized in that: The cleaning device comprises: motor; an operating switch configured to be manually operated to switch the rotation direction of the motor to forward or reverse; a front end connection portion configured to be connectable to the front end attachment and to be rotated by the driving force of the motor; a plurality of first claws, the plurality of first claws being arranged on the front end connecting portion along the circumferential direction of the rotation axis of the front end connecting portion, wherein the plurality of first claws are configured to engage with the plurality of second claws corresponding to the front end connecting portion rotating in the forward direction, and to separate from the plurality of second claws corresponding to the front end connecting portion rotating in the reverse direction, and the plurality of second claws are provided on the front end attachment; and A control unit is configured to control the driving of the motor, wherein the control unit is configured to stop the motor when the motor rotates in the reverse direction based on the fact that a first condition related to the rotation state of the front end connecting portion is satisfied.

2. The cleaning device according to claim 1, characterized in that: The first condition is satisfied when the front end connecting portion is rotated in the reverse direction by an angle greater than the engagement angle. The engagement angle corresponds to an area in which (i) the first claw and the second claw overlap and (ii) an engagement force is generated between the first claw and the second claw, wherein the first claw is included in the plurality of first claws and the second claw is included in the plurality of second claws.

3. The cleaning device according to claim 1, characterized in that: The first condition is satisfied when the front end connecting portion rotates in the reverse direction for a predetermined time, and the predetermined time corresponds to the rotation speed of the motor and the engagement angle. The engagement angle corresponds to an area in which (i) the first claw and the second claw overlap and (ii) an engagement force is generated between the first claw and the second claw, wherein the first claw is included in the plurality of first claws and the second claw is included in the plurality of second claws.

4. The cleaning device according to claim 2 or 3, characterized in that: The control unit is configured to change the rotation direction to the forward direction based on a condition that a second condition related to a driving state of the motor is satisfied while the motor is rotating in the reverse direction.

5. The cleaning device according to claim 4, characterized in that: The second condition is satisfied when the front end connecting portion rotates in the reverse direction by an angle equal to or greater than the engagement angle while the motor is subjected to a load equal to or greater than a load threshold.

6. The cleaning device according to claim 4 or 5, characterized in that: The second condition is satisfied when the number of driving times is equal to or greater than the predetermined number of times. The driving times are: the number of times the motor has been driven in the reverse direction, One driving operation corresponds to a period from when the motor starts rotating to when it stops rotating.

7. The cleaning device according to any one of claims 1 to 6, characterized in that: The control unit is composed of: In response to the rotation direction being switched to the reverse direction by the operation switch, a signal is obtained, which indicates whether the front attachment mounted on the front connecting portion by the plurality of first claws is pressed against the ground. The motor is immediately stopped based on the fact that the acquired signal indicates that the front attachment is not pressed against the ground.

8. The cleaning device according to claim 7, characterized in that: The cleaning device further includes: a drive circuit configured to control a voltage applied to the motor; The control unit is composed of: In response to the rotation direction being switched to the reverse direction by the operation switch, (i) the drive circuit is controlled so as to apply a first voltage to the motor, and (ii) the signal is acquired. Based on the fact that the acquired signal indicates that the front attachment is pressed against the ground, a second voltage higher than the first voltage is applied to the motor.

9. The cleaning device according to claim 8, characterized in that: The control unit is composed of: In response to the rotation direction being switched to the reverse direction by the operation switch, (i) the drive circuit is controlled so as to apply a pulse width modulation signal having a first duty cycle to the motor, and (ii) the signal is acquired. The first duty ratio is gradually increased based on the fact that the acquired signal indicates that the front attachment is pressed against the ground.

10. The cleaning device according to any one of claims 7 to 9, characterized in that: The control unit is configured to acquire the signal based on a rotation state of the motor.

11. A method for controlling a motor of a cleaning device, characterized in that: The control method of the motor of the cleaning device comprises the following steps: Rotate the motor in the reverse direction so that the plurality of first claws are separated from the plurality of second claws, wherein the plurality of first claws are arranged on the front end connecting portion along the circumferential direction of the rotation axis of the front end connecting portion, the front end connecting portion is configured to be connectable to the front end attachment and rotated by the driving force of the motor, the plurality of second claws are provided on the front end attachment, and the plurality of first claws are engaged with the plurality of second claws corresponding to the rotation of the motor in the forward direction; and During the process of the motor rotating in the reverse direction, the motor is stopped based on a condition that a predetermined condition related to the rotation state of the front end connecting portion is satisfied.

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