Cleaning device

Abstract

To provide a cleaning device that allows the removal of a tip attachment for cleaning without pressing it against a floor surface.SOLUTION: A motor rotates a tip connection section from a specified position in the first rotational direction to attach a cleaning tool to the tip connection section. The cleaning tool has a higher inertial moment that the inertial moment of the tip connection section. A control unit rotates the motor in the first rotational direction in the first mode. The first mode is the mode for performing cleaning. The control unit drives the motor so as to generate a release force in the first rotational direction in the cleaning tool in the second mode. The release force has magnitude that may release the engagement between an engagement section and an engaged section.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a cleaning device having a detachable tip attachment. [Background technology]

[0002] The scrubber described in Patent Document 1 includes a motor and a motor adapter fixed to the shaft of the motor. A rotary cleaner is attached to the motor adapter. The rotary cleaner has a brush used for cleaning. The rotary cleaner includes three locking flanges, and the motor adapter includes three locking claws.

[0003] When attaching the rotary cleaner to the motor adapter, rotate the motor in the forward direction with the motor adapter in the designated position on the rotary cleaner, causing the three locking flanges to engage with the three locking claws and attaching the rotary cleaner to the motor adapter.

[0004] When removing the rotary cleaner from the motor adapter, the friction between the rotary cleaner and the floor is utilized. That is, while the rotary cleaner is pressed against the floor, the switch is operated to rotate the motor in the reverse direction. This releases the engagement between the three locking flanges and the three locking claws, allowing the user to remove the rotary cleaner from the motor adapter. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 7-327897 Summary of the Invention [Problem to be solved by the invention]

[0006] In the above-mentioned scrubber, in order to remove the rotary cleaning tool, it is necessary to operate a switch while the rotary cleaning tool is pressed against the floor surface. Therefore, a user is required to perform a complicated operation to remove the rotary cleaning tool. In addition, reversing the rotation of the rotary cleaning tool while it is pressed against the floor surface is an operation different from that during normal operation. Therefore, the user is required to pay attention to the behavior of the scrubber when it is reversed. From this viewpoint, the method of removing the rotary cleaning tool in the above-mentioned scrubber is troublesome for the user.

[0007] One aspect of the present disclosure provides a cleaning device in which a cleaning tool (corresponding to the above-mentioned rotary cleaning tool) for cleaning can be removed without being pressed against a floor surface. [Means for solving the problem]

[0008] A cleaning device according to one aspect of the present disclosure includes a motor, a drive circuit, a tip connector, a switch, and a controller. The drive circuit supplies power to the motor to drive the motor. The cleaning tool is removably attached to the tip connection part. The tip connection part is rotated in a first rotation direction or a second rotation direction by the motor. The tip connection part has an engaging part, and the cleaning tool has an engaged part. When the tip connection part is rotated in the first rotation direction from a specified position with respect to the cleaning tool that is detached from the tip connection part, the engaging part engages with the engaged part, and the cleaning tool is attached to the tip connection part. The tip connection part has a moment of inertia smaller than the moment of inertia of the cleaning tool. The switch is manually operated to selectively switch the operation mode of the motor between a first mode for cleaning with the cleaning tool and a second mode for detaching the cleaning tool from the tip connection part.

[0009] In the first mode, the control unit rotates the motor in a first rotation direction via the drive circuit. In the second mode, the control unit executes release control. The release control includes controlling the drive circuit so that a release force is generated in the cleaning tool by the rotation of the motor. The release force is a relative force in the first rotation direction with respect to the tip connection portion. The release force has a magnitude that can release the engagement between the engaging portion and the engaged portion.

[0010] In such a cleaning device, by operating the motor in the second mode, the cleaning tool can be removed without being pressed against an external structure such as a floor surface. [Brief description of the drawings]

[0011] [Figure 1] 1 is a diagram showing the appearance of a cleaning device according to a first embodiment. FIG. [Diagram 2] 3A and 3B are diagrams illustrating a display unit of the cleaning device according to the first embodiment. [Diagram 3] 3A and 3B are diagrams showing a tip attachment connected to the cleaning device according to the first embodiment. [Figure 4] 1A is a diagram showing the underside of a tip attachment according to a first example of the first embodiment. FIG. [Figure 5A] 4 is a diagram showing the underside of the tip connection part of the cleaning device according to the first embodiment. FIG. [Figure 5B] FIG. 2 is a perspective view of a tip connection portion of the cleaning device according to the first embodiment. [Figure 6] FIG. 2 is a diagram showing a state in which a tip attachment according to a first example is connected to a tip connection portion of the cleaning device according to the first embodiment. [Figure 7] 13 is a diagram showing the underside of a tip attachment according to a second example of the first embodiment. FIG. [Figure 8] 13 is a diagram showing a state in which a tip attachment according to a second example is connected to the tip connection portion of the cleaning device according to the first embodiment. FIG. [Figure 9] 5 is a diagram showing an engagement angle between a first prong of the cleaning device and a second prong of the brush according to the first embodiment. FIG. [Figure 10] 3 is a diagram showing a cross section taken along a radial direction of a first claw of the cleaning device according to the first embodiment. FIG. [Figure 11] 3 is a diagram showing a cross section along a radial direction of a first claw and a second claw engaged with the first claw of the cleaning device according to the first embodiment. FIG. [Figure 12] 3 is a diagram showing a cross section taken along a circumferential direction of a first claw of the cleaning device according to the first embodiment. FIG. [Figure 13] 3 is a diagram showing a cross section along a circumferential direction of a first claw and a second claw engaged with the first claw of the cleaning device according to the first embodiment. FIG. [Figure 14] 2 is a block diagram showing the electrical configuration of the cleaning device according to the first embodiment. FIG. [Figure 15] 5 is a flowchart showing a main process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 16] 5 is a flowchart showing an interrupt process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 17] 5 is a flowchart showing a switch operation detection process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 18] 5 is a flowchart showing a power management process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 19] 6 is a flowchart showing a main power supply state off determination process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 20] 6 is a flowchart showing an automatic off determination process of a main power supply state executed by a control circuit of the cleaning device according to the first embodiment. [Figure 21] 5 is a flowchart showing a motor control process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 22] 5 is a flowchart showing a speed mode setting process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 23A] 6 is a flowchart showing a first part of a detachment mode setting process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 23B] 10 is a flowchart showing a second part of the detachment mode setting process executed by the control circuit of the cleaning device according to the first embodiment. [Figure 23C] 10 is a flowchart showing a third part of the detachment mode setting process executed by the control circuit of the cleaning device according to the first embodiment. [Figure 24]13 is a flowchart showing a modified example of the third part of the removal mode setting process executed by the control circuit of the cleaning device according to the first embodiment. [Diagram 25] 5 is a diagram showing target rotation speeds according to speed modes of the motor of the cleaning device according to the first embodiment. FIG. [Figure 26] 6 is a flowchart showing an automatic-off determination process in a detachment mode executed by a control circuit of the cleaning device according to the first embodiment. [Figure 27] 5 is a flowchart showing a state transition process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 28] 5 is a flowchart showing a first output calculation process executed by a control circuit of the cleaning device according to the first embodiment. [Figure 29] 6 is a flowchart showing a second output calculation process executed by the control circuit of the cleaning device according to the first embodiment. [Diagram 30] 5 is a flowchart showing a moment of inertia estimation process executed by a control circuit of the cleaning device according to the first embodiment. [Diagram 31] 4 is a flowchart showing an inverter control process executed by a control circuit of the cleaning device according to the first embodiment. [Diagram 32] 5 is a flowchart showing an INV control process executed by a control circuit of the cleaning device according to the first embodiment. [Diagram 33] 10 is a flowchart showing an interrupt process executed by a control circuit of a cleaning device according to a second embodiment. [Diagram 34] 10 is a flowchart showing a motor control process executed by a control circuit of a cleaning device according to a second embodiment. [Diagram 35] 13 is a flowchart showing a third part of the detachment mode setting process executed by the control circuit of the cleaning device according to the second embodiment. [Diagram 36] 13 is a flowchart showing a first example of a process for obtaining a reverse rotation angle of a tip connector, which is executed by a control circuit of a cleaning device according to a second embodiment. [Figure 37]13 is a flowchart showing a second example of the process for obtaining the reverse rotation angle of the tip connector, which is executed by the control circuit of the cleaning device according to the second embodiment. [Figure 38] 13 is a flowchart showing an automatic stop determination process in a removal mode executed by a control circuit of a cleaning device according to a second embodiment. [Figure 39] 10 is a flowchart showing a first automatic stop determination process executed by a control circuit of a cleaning device according to a second embodiment. [Diagram 40] 10 is a flowchart showing a second automatic stop determination process executed by a control circuit of the cleaning device according to the second embodiment. [Diagram 41] 13 is a flowchart showing a third automatic stop determination process executed by a control circuit of the cleaning device according to the second embodiment. [Diagram 42] 10 is a flowchart showing a rotation direction setting process executed by a control circuit of a cleaning device according to a second embodiment. [Diagram 43] 10 is a flowchart showing a state transition process executed by a control circuit of a cleaning device according to a second embodiment. [Diagram 44] 10 is a flowchart showing an output calculation process executed by a control circuit of a cleaning device according to a second embodiment. [Diagram 45] 10 is a flowchart showing a reverse rotation angle calculation process executed by a control circuit of a cleaning device according to a second embodiment. [Figure 46] 10 is a flowchart showing an inverter control process executed by a control circuit of a cleaning device according to a second embodiment. [Figure 47] 13 is a flowchart showing an INV control process executed by a control circuit of a cleaning device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] [Summary of the embodiment] An embodiment may provide a cleaning device having at least one of the following features 1 to 11. Feature 1: Motor. Feature 2: A drive circuit configured to supply power to a motor to drive the motor. -Feature 3: A tip connection portion configured to allow the cleaning tool to be detachably attached. Feature 4: The tip connection part is rotated in a first rotation direction or a second rotation direction by the motor. Feature 5: The tip connection part has an engaging part, and the cleaning tool has an engaged part. When the tip connection part is rotated in a first rotation direction from a specified position with respect to the cleaning tool detached from the tip connection part, the engaging part engages with the engaged part, and the cleaning tool is attached to the tip connection part. Feature 6: The tip connection part has a moment of inertia smaller than the moment of inertia of the cleaning tool. Feature 7: A switch configured to be manually operated to selectively switch an operation mode of a motor between a first mode and a second mode. The first mode is an operation mode for performing cleaning with a cleaning tool. The second mode is an operation mode for detaching the cleaning tool from the tip connection part. Feature 8: Control unit. Feature 9: In the first mode, the control unit causes the motor to rotate in the first rotation direction via the drive circuit. Feature 10: In the second mode, the control unit executes the release control. Feature 11: The release control includes controlling the drive circuit so that a release force is generated in the cleaning tool by the rotation of the motor. The release force is a relative force in the first rotation direction based on the tip connection part. The release force has a magnitude that can release the engagement between the engaging part and the engaged part.

[0013] In a cleaning device having at least Features 1-11, by operating the motor in the second mode, the cleaning tool can be removed without pressing the cleaning tool against an external structure such as a floor surface.

[0014] In the first mode, the controller may rotate the motor in the first direction of rotation without generating a release force, or may allow a force to be generated on the cleaner in the first mode that is smaller than a release force in the second mode.

[0015] An embodiment may include the following feature 12 and / or feature 13 in addition to or instead of at least one of features 1-11 described above. Feature 12: The control unit is configured to rotate the motor in the first rotation direction in the second mode. Feature 13: The release control includes applying a first brake to the motor via the drive circuit to decelerate the motor in response to a predetermined brake initiation requirement for initiating braking of the motor being satisfied, thereby generating a release force in the cleaning tool.

[0016] In a cleaning device having at least the features 1-13, the release force can be easily generated by deceleration caused by the first brake. Some embodiments may include the following feature 14 and / or feature 15 in addition to or instead of at least one of features 1-13 above. Feature 14: A speed detection unit configured to detect an actual rotation speed of the motor. Feature 15: The brake initiation requirement is met based on the actual rotation speed detected by the speed detection unit being equal to or greater than the first rotation speed threshold value.

[0017] A cleaning device having at least features 1-15 is able to properly determine brake initiation requirements. Some embodiments may include the following feature 16 and / or feature 17 in addition to or instead of at least one of features 1-15 above. Feature 16: In the second mode, the control unit is configured to control the drive circuit so that the motor accelerates from a stopped state toward the target rotation speed. Feature 17: The brake start requirement is met based on the lapse of a threshold time from the start of driving the motor.

[0018] A cleaning device having at least features 1-13, 16, and 17 is capable of properly determining brake initiation requirements. Some embodiments may include the following feature 18 in addition to or instead of at least one of features 1-17 above. Feature 18: In the second mode, in response to the brake initiation requirement being satisfied, the control unit is configured to control the drive circuit to open a path for supplying power from the drive circuit to the motor to coast the motor for a first time period before applying a first brake to the motor.

[0019] Some embodiments may include the following feature 19 in addition to or instead of at least one of features 1-18 above. Feature 19: In the first mode, when a first stop requirement for stopping the motor is satisfied, the control unit is configured to control the drive circuit to coast the motor in the same manner as described above without applying a brake to the motor.

[0020] Some embodiments may include the following feature 20 in addition to or instead of at least one of features 1-19 above. Feature 20: The control unit is configured to apply a second brake having a weaker braking force than the first brake to the motor via the drive circuit in response to the first stop requirement being satisfied in the first mode.

[0021] A cleaning device having at least features 1-13 and 20 can apply brakes with appropriate strength depending on the operating mode. An embodiment may include the following feature 21 in addition to or instead of at least one of the features 1-20 described above. Feature 21: In the first mode, the control unit is configured to control the drive circuit so as to coast the motor in the same manner as described above for a second time period before applying a second brake to the motor in response to the first stop requirement being satisfied.

[0022] An embodiment may include the following feature 22 and / or feature 23 in addition to or instead of at least one of features 1-21 described above. · Feature 22: The second time is shorter than the first time. Feature 23: The control unit is configured to apply a second brake to the motor via the drive circuit after the second time period has elapsed.

[0023] Some embodiments may include the following feature 24 and / or feature 25 in addition to or instead of at least one of features 1-23 above. · Feature 24: The motor is a brushless motor with three terminals for receiving power. Feature 25: The second brake includes a two-phase short-circuit brake that electrically shorts any two of the three terminals of the motor.

[0024] A cleaning device having at least the features 1-13, 20, 24, and 25 can apply brakes with appropriate strength according to the first mode. Some embodiments may include the following feature 26 in addition to or instead of at least one of features 1-25 above. Feature 26: The first brake includes a three-phase short-circuit brake that electrically shorts three terminals of the motor to each other.

[0025] A cleaning device having at least features 1-13 and 26 can apply brakes with appropriate strength according to the second mode. An embodiment may include the following feature 27 in addition to or instead of at least one of features 1-26 above. Feature 27: The release control includes generating a release force in the cleaning tool by controlling the drive circuit to accelerate the motor from a stopped state in the second rotation direction at a first acceleration.

[0026] In a cleaning device having at least features 1-13 and 27, the release force can be easily generated by acceleration. Some embodiments may include the following feature 28 in addition to or instead of at least one of features 1-27 above. Feature 28: In the first mode, the control unit is configured to accelerate the motor at a second acceleration lower than the first acceleration when driving the motor.

[0027] A cleaning device having at least the features 1-13, 27, and 28 can start driving the motor with appropriate acceleration depending on the operation mode. Some embodiments may include the following feature 29 in addition to or instead of at least one of features 1-28 above. Feature 29: The release control includes stopping the motor in response to a second stop requirement being satisfied after the motor starts to be driven.

[0028] A cleaning device having at least the features 1-13, 27, and 29 can stop the motor at an appropriate time in the second mode. Some embodiments may include the following feature 30 in addition to or instead of at least one of features 1-29 above. Feature 30: The second stop requirement is satisfied based on the actual rotational speed of the motor exceeding a second rotational speed threshold.

[0029] A cleaning device having at least the features 1-13, 27, 29, and 30 can stop the motor at an appropriate time in the second mode. An embodiment may include the following feature 31 in addition to or instead of at least one of the features 1-30 above. Feature 31: The second stop requirement is satisfied based on the rotation angle of the tip connection part in the second rotation direction from when the motor starts to be driven exceeding an angle threshold value.

[0030] A cleaning device having at least the features 1-13, 27, 29, and 31 can stop the motor at an appropriate time in the second mode. An embodiment may include the following feature 32 in addition to or instead of at least one of the features 1-31 above. Feature 32: The second stop requirement is satisfied when the elapsed time from when the motor started to be driven exceeds an elapsed time threshold.

[0031] A cleaning device having at least the features 1-13, 27, 29, and 32 can stop the motor at an appropriate time in the second mode. An embodiment may include the following feature 33 in addition to or instead of at least one of the features 1-32 above. Feature 33: The control unit is configured to switch the operation mode to the first mode based on the fact that the motor has been driven in the second mode a predetermined number of times or more in succession.

[0032] A cleaning device having at least Features 1-11 and 33 can prevent the motor from being unintentionally driven excessively in the second mode. Some embodiments may include the following feature 34 in addition to or instead of at least one of features 1-33 above. Feature 34: The cleaning device includes a grip configured to be held by a user of the cleaning device, and the cleaning device is a handheld type that is used while being supported by the user via the grip.

[0033] In some embodiments, any combination of features 1-34 above may be used. In some embodiments, any of features 1-34 above may be excluded. In an embodiment, the control unit may be in the form of a control circuit, which may be integrated into a single electronic unit or a single electronic device or a single circuit board.

[0034] In one embodiment, the control circuit may be a combination of two or more electronic circuits, two or more electronic units, or two or more electronic devices that are provided separately within the electric operating machine.

[0035] In one embodiment, the control circuitry may comprise a microcomputer (or microcontroller or microprocessor), hard-wired logic, an application specific integrated circuit (ASIC), an application specific general purpose product (ASSP), a programmable logic device (e.g., a field programmable gate array (FPGA)), discrete electronic components, and / or combinations thereof.

[0036] Specific Exemplary Embodiments [1. First embodiment] (1-1) Overall configuration of the cleaning device The configuration of the cleaning device 1 of the first embodiment will be described with reference to FIG. 1. The cleaning device 1 is used for polishing work such as removing dirt from floor surfaces and wax polishing. The cleaning device 1 according to this embodiment is a handheld type. The cleaning device 1 includes a main body 10, a rod 11, a support 6, a head 5, and a tip connection part 30. The rod 11 has a rod-like or cylindrical shape and extends vertically. The main body 10 has a cylindrical shape with a larger diameter than the rod 11 and extends vertically. The main body 10 is disposed above the rod 11 and accommodates the rod 11 therein. The main body 10 also accommodates a controller 50 (see FIG. 14) therein.

[0037] The main body 10 includes a first grip portion 12 formed in a T-shape at the upper end of the main body 10. The first grip portion 12 is gripped by a user of the cleaning device 1. The main body 10 includes a trigger 14 disposed on the rear surface of the first grip portion 12. The trigger 14 is configured so as to be pulled by the hand gripping the first grip portion 12. In response to being pulled by the user, the trigger 14 outputs a trigger signal indicating ON to a control circuit 60 described below. In response to being released by the user, the trigger 14 outputs a trigger signal indicating OFF to the control circuit 60.

[0038] The main body 10 includes a display unit 155 on the surface of the first grip portion 12. Furthermore, the main body 10 includes an operation unit 150 below the display unit 155. The display unit 155 and the operation unit 150 are electrically connected to the control circuit 60 by lead wires that pass through the inside of the main body 10. The operation unit 150 and the display unit 155 are shown in FIG.

[0039] The operation unit 150 includes a main power supply / speed mode changeover switch 153. The main power supply / speed mode changeover switch 153 is operated by a user to (i) turn on or off the main power supply of the cleaning device 1, and (ii) select the speed mode of the motor 70. The main power supply / speed mode changeover switch 153 outputs a main power supply signal indicating ON to the control circuit 60 in response to being pressed by the user. If the ON state of the main power supply signal continues for a predetermined time or more, the main power supply switches from ON to OFF or from OFF to ON. Also, if the main power supply signal switches from ON to OFF before the ON state of the main power supply signal continues for a predetermined time or more, the speed mode switches from the set mode to the next mode. The speed mode switches in the order of low speed mode → medium speed mode → high speed mode → low speed mode.

[0040] That is, each time the user presses and holds the main power / speed mode changeover switch 153, the main power is switched between on and off. A long press means that the user continues to press the main power / speed mode changeover switch 153 for a predetermined period of time or longer. When the user turns on the main power and pulls the trigger 14, the motor 70 (see FIG. 14) is driven. When the user turns off the main power or releases the trigger 14, the motor 70 stops.

[0041] Furthermore, each time the user briefly presses main power / speed mode changeover switch 153, the speed mode switches in the following order: low speed mode → medium speed mode → high speed mode → low speed mode. A short press refers to the user releasing main power / speed mode changeover switch 153 before a predetermined time has elapsed since pressing it.

[0042] The operation unit 150 includes a removal mode switch 154. When pressed by a user, the removal mode switch 154 outputs a removal mode signal indicating ON to the control circuit 60. The removal mode switch 154 is pressed by the user when the user removes the tip attachment 20. 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.

[0043] The display unit 155 includes a speed display unit 151. The speed display unit 151 includes three light-emitting diodes (LEDs) corresponding to a high speed mode, a medium speed mode, and a low speed mode. Of the three LEDs of the speed display unit 151, an LED corresponding to a speed mode set via the main power supply / speed mode changeover switch 153 is turned on. In addition, the speed display unit 151 blinks the three LEDs while the motor 70 is rotating in the reverse direction.

[0044] The display unit 155 includes an error display unit 152. The error display unit 152 includes one LED, which lights up when the control circuit 60 detects an error that requires protection of the cleaning device 1 or the battery pack 40.

[0045] The main body 10 includes a battery mounting section 41 on the upper surface of the main body 10 and behind the first grip section 12. A removable battery pack 40 is slidably mounted in the battery mounting section 41. The battery pack 40 mounted in the battery mounting section 41 is electrically connected to the controller 50. The battery pack 40 includes a chargeable and dischargeable secondary battery. The secondary battery is, for example, a lithium ion battery, and includes a plurality of battery cells connected in series.

[0046] The main body 10 includes a second grip portion 13 at the front and lower end of the main body 10. The second grip portion 13 is formed in a rectangular shape and protrudes forward from the front surface of the main body 10. The second grip portion 13 is gripped by the user.

[0047] A user can use the cleaning device 1 by holding the first grip part 12 and / or the second grip part 13 to support and move the cleaning device 1. In other words, the cleaning device 1 of the first embodiment is in the form of a so-called handheld type (or handy type or handheld type).

[0048] The support part 6 is attached to the lower end of the rod part 11. The support part 6 has a bifurcated shape on the lower end side. The head unit 5 is disposed below the support unit 6 and supported by being sandwiched between the forked portions of the support unit 6. The head unit 5 incorporates a motor 70 and a speed reduction mechanism 75 (see FIG. 14). In this embodiment, the motor 70 is a three-phase brushless motor. The speed reduction mechanism 75 is connected to a rotating shaft 77 of the motor 70, and reduces the rotational speed of the motor 70 before outputting it. The motor 70 is electrically connected to the controller 50 by lead wires that pass through the inside of the rod unit 11 and the main body unit 10.

[0049] The tip connection part 30 is formed in a disk or cylinder shape and is disposed at the lower end of the head part 5. The tip connection part 30 has a load shaft 80. The load shaft 80 is connected to a rotating shaft 77 of the motor 70 via a reduction mechanism 75. Therefore, the tip connection part 30 rotates by receiving the driving force of the motor 70. That is, when the motor 70 rotates in the forward direction, the tip connection part 30 rotates in the forward direction, and when the motor 70 rotates in the reverse direction, the tip connection part 30 rotates in the reverse direction. The tip attachment 20 is detachably attached to the lower surface of the tip connection part 30. Details of the tip connection part 30 will be described later.

[0050] The tip attachment 20 is a tool for polishing floor surfaces and the like, and has a disk-shaped member. The tip attachment 20 is attached to the tip connection part 30 so that the center of the disk-shaped member coincides with the load shaft 80. The tip attachment 20 is, for example, a brush in which a tuft of bristles is attached to a disk-shaped resin member, or a pad base for fixing a disk-shaped pad made of nonwoven nylon or polyester fabric. In this embodiment, the tip attachment 20 is a brush.

[0051] In the first embodiment, in the basic mode for performing cleaning work, the motor 70 rotates in the forward direction. That is, the cleaning work is performed while rotating the tip connection part 30 in the forward direction. In the removal mode for removing the tip attachment 20, the motor 70 also rotates in the forward direction, as described later. On the other hand, in the removal mode in the second embodiment described later, the motor 70 rotates in the reverse direction.

[0052] (1-2) Configuration of the tip connection part and tip attachment The configuration of the tip connection part 30 and the tip attachment 20 will be described with reference to Figs. 3 to 13. Fig. 3 shows the top surface of the tip attachment 20. The tip attachment 20 includes a first annular part 21, a second annular part 28, and a third annular part 22. The first annular part 21 is the outermost annular member, and a tuft of bristles is attached to the lower surface of the first annular part 21. The second annular part 28 is an annular part adjacent to the inner side of the first annular part 21 in the radial direction, and is located lower than the first annular part 21. The second annular part 28 has ribs 235, 245, and 255. The ribs 235, 245, and 255 are arranged at equal intervals along the circumferential direction of the second annular part 28. The second annular part 28 is screwed to the first annular part 21 via the ribs 235, 245, and 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.

[0053] Second claws 23, 24, 25 that engage with first claws 33, 34, 35 described below are attached to the third annular portion 22. The second claws 23, 24, 25 are plate-like members having an arc shape, and are arranged at equal intervals along the circumferential direction of the load shaft 80, i.e., along the circumferential direction of the third annular portion 22, so as to protrude radially inward.

[0054] FIG. 4 shows a first example of the lower surface of the second annular portion 28 and the third annular portion 22. The second claws 23, 24, and 25 have the same shape. The second claw 23 includes a protrusion 231, a first region 232, and a second region 233. The protrusion 231 is disposed in the center of the second claw 23 in the circumferential direction and protrudes downward. The first region 232 is a region on the forward rotation side with respect to the protrusion 231. The second region 233 is a region on the reverse rotation side with respect to the protrusion 231. Similarly, the second claw 24 includes a protrusion 241, a first region 242, and a second region 243, and the second claw 25 includes a protrusion 251, a first region 252, and a second region 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.

[0055] 5A and 5B, the tip connection part 30 includes an outer annular part 31 and an inner annular part 38. The outer annular part 31 is an annular member disposed on the outside. The inner annular part 38 is an annular member adjacent to the inner side of the outer annular part 31 in the radial direction, and is disposed below the outer annular part 31.

[0056] The first claws 33, 34, 35 are attached to 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, i.e., along 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.

[0057] 5B, the first claws 33, 34, 35 are disposed below the outer annular portion 31. The reverse rotation side ends in the circumferential direction of the first claws 33, 34, 35 are connected to the outer annular portion 31. The forward rotation side ends in the circumferential direction of the first claws 33, 34, 35 are separated from the outer annular portion 31. That is, there is a gap between the forward rotation side ends and the outer annular portion 31 in the up-down direction.

[0058] 6 shows the underside of the tip connection part 30 in a state where the second claws 23, 24, 25 are engaged with the first claws 33, 34, 35. When attaching the tip attachment 20, the tip attachment 20 is placed on the floor, and the tip connection part 30 is brought over it. At this time, the first claws 33, 34, 35 of the tip connection part 30 are aligned so as to be directly above the gaps 261, 262, 263 of the tip attachment 20. In this state, the tip connection part 30 is lowered, and the first claws 33, 34, 35 are passed through the gaps 261, 262, 263. The position of the tip connection part 30 at this time (specifically, the relative position with respect to the tip attachment 20) is referred to as the specified position.

[0059] By rotating the tip connection part 30 arranged at a specified position in the forward direction, the second claws 23, 24, 25 engage with the first claws 33, 34, 35. In detail, 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 engages with the first claw 33. When the second claw 23 engages with the first claw 33, the second region 233 is sandwiched between the outer annular part 31 and the first claw 33, which generates an engagement force. The second claw 23 engages with the first claw 33 due to this engagement force. Similarly, the second claw 24 engages with the first claw 34, and the second claw 25 engages with the first claw 35. This causes the tip attachment 20 to be attached to the tip connection portion 30.

[0060] That is, in the first embodiment, the engagement of the second claw 23 with the first claw 33 means that the second claw 23 is sandwiched in the gap between the first claw 33 and the outer ring portion 31. In other words, the engagement of the second claw 23 with the first claw 33 means that the second claw 23 is fixed to the first claw 33 by the frictional force between the second claw 23 and the first claw 33 (more specifically, the frictional force between the second claw 23 and the first claw 33 and the outer ring portion 31) generated by the second claw 23 being sandwiched in the gap. That is, the frictional force corresponds to the above-mentioned engagement force. The same is true for the engagement of the second claw 24 with the first claw 34 and the engagement of the second claw 25 with the first claw 35.

[0061] When the tip connection part 30 to which the tip attachment 20 is attached is rotated in the opposite direction relative to the tip attachment 20 by an angle corresponding to the engagement angle Af (see FIG. 9), the tip attachment 20 is detached from the tip connection part 30. Specifically, the first claws 33, 34, 35 move toward the positions of the gaps 261, 262, 263 and move away from the second claws 23, 24, 25. This releases the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25. When the tip connection part 30 is further rotated in the opposite direction from that state and the first claws 33, 34, 35 reach the gaps 261, 262, 263, the tip attachment 20 is detached from the tip connection part 30.

[0062] The engagement angle Af is smaller than the overlap angle A4. As shown in Fig. 6, the overlap angle A4 corresponds to the area where the first claws 33, 34, 35 overlap with the second claws 23, 24, 25. In other words, the overlap angle A4 corresponds to the angle of the arc-shaped area where the first claws 33, 34, 35 overlap with the second claws 23, 24, 25.

[0063] 7 shows a second example of the underside of the second annular portion 28 and the third annular portion 22. The second claws 23, 24, 25 of the second example are smaller than the second claws 23, 24, 25 of the first example. Therefore, as shown in FIG. 8, the overlap angle A4 is smaller than that of the first example. That is, the overlap angle A4 changes depending on the shape of the tip attachment 20.

[0064] With reference to FIG. 9, a method of calculating the overlap angle A4 will be 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, and in this embodiment, the first angle A1 is 120 degrees. The second angle A2 is an angle corresponding to the circumferential width of the rib 255, and is, for example, 10 degrees. The larger the second angle A2 is, the smaller the overlap angle A4 is. The third angle A3 is an angle corresponding to the margin of the gap 263 with respect to the first claw 35, and is, for example, 10 degrees. The larger the third angle A3 is, the smaller the overlap angle A4 is. If the third angle A3 is 0 degrees, it becomes difficult to attach the tip attachment 20 to the tip connection part 30.

[0065] The overlap angle A4 is calculated by overlap angle A4=(first angle A1-second angle A2-third angle A3) / 3. By rotating the tip connection part 30 in the opposite direction by a value larger than the overlap angle A4, the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25 is released. However, in reality, the entire area corresponding to the overlap angle A4 does not generate an engagement force (or a friction force or a bonding force) between the first claws 33, 34, 35 and the second claws 23, 24, 25. A part of the entire area corresponding to the overlap angle A4 generates an engagement force, and the remaining part serves as an insertion guide for the second area 233, 243, 253. The engagement angle Af corresponds to the area corresponding to the overlap angle A4 where an engagement force is generated between the first claws 33, 34, 35 and the second claws 23, 24, 25. That is, the engagement angle Af corresponds to the region where the first claws 33, 34, 35 overlap with the second claws 23, 24, 25 and where an engagement force is generated between the first claws 33, 34, 35 and the second claws 23, 24, 25 (i.e., the region where they are sandwiched and in contact with each other).

[0066] FIG. 10 shows a schematic 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 with respect to a plane perpendicular to the up-down direction. Therefore, the distance between the first claw 33 and the outer annular portion 31 narrows from the inside to the outside in the radial direction. As shown in FIG. 11, 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, and the second region 233 is sandwiched between the first claw 33 and the outer annular portion 31. As a result, an engagement force is generated between the first claw 33 and the second claw 23.

[0067] FIG. 12 shows a schematic cross section of the first claw 33 along the circumferential direction. The first claw 33 has a first portion and a second portion. The first portion is inclined at an angle BB with respect to a plane perpendicular to the vertical direction and is located on the forward rotation side relative to the second portion. The second portion is parallel to the plane perpendicular to the vertical direction and is connected to the outer annular portion 31. The gap between the first portion and the outer annular portion 31 becomes wider from the boundary with the second portion toward the end of the forward rotation side. The first portion serves as an insertion guide for the second claw 23. As shown in FIG. 13, when the second region 233 of the second claw 23 enters from the end of the first portion, the second region 233 interferes with (i.e., abuts against) the first portion, and an engagement force begins to be generated. As the second region 233 advances further from the position where the interference begins, the second region 233 advances into the gap between the second portion of the first claw 33 and the outer annular portion 31, and the engagement force between the first claw 33 and the second claw 23 increases. The engagement angle Af is an angle corresponding to the region generating this engagement force. The engagement angle Af is smaller than the overlap angle A4, and in this embodiment, is half the overlap angle A4.

[0068] Therefore, by rotating the tip connection part 30 in the opposite direction by an engagement angle Af or more and less than 360 degrees, the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25 is released. Preferably, by rotating the tip connection part 30 in the opposite direction by an overlap angle A4 or more and less than 360 degrees, the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25 is released.

[0069] Thus, in the first embodiment, the tip attachment 20 is engaged with the tip connection part 30 by an engagement force (i.e., a frictional force). Therefore, the engaged state is maintained unless a force in the normal rotation direction (a force relative to the tip connection part 30) (hereinafter referred to as a "release force") greater than the frictional force is applied to the tip attachment 20. The release force has a magnitude that can release the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25.

[0070] When a release force is applied to the tip attachment 20, the tip attachment 20 moves in the normal rotation direction relative to the tip connection part 30, thereby releasing the engaged state. Note that the moment in the normal rotation direction of the tip attachment 20 relative to the tip connection part 30 that can release the engaged state (i.e., the moment that can generate a release force in the engaged part) is hereinafter referred to as the "release moment".

[0071] When a release moment occurs in the tip attachment 20, a release force greater than the engagement force occurs at the engagement portion with the tip connection part 30. This causes the engagement state to be released. If a release moment can be generated in the tip attachment 20, the tip attachment 20 can be removed without touching the tip attachment 20 and while the tip attachment 20 is separated from the floor surface.

[0072] There are various possible methods for generating a release moment in the tip attachment 20. In the present first embodiment, the moment of inertia of the tip attachment 20 is greater than the moment of inertia of the tip connection part 30. Therefore, in the present first embodiment, such a difference in the moments of inertia is utilized to generate a release moment, which allows the tip attachment 20 to be removed. Specifically, as described below, when removing the tip attachment 20, the rotating motor 70 is suddenly decelerated to generate a release moment in the tip attachment 20. This allows the tip attachment 20 to be removed.

[0073] The moment of inertia of the tip connection part 30 in this specification may literally mean the moment of inertia of only the tip connection part 30. Alternatively, it may mean the moment of inertia of the entire driven body including, in addition to the tip connection part 30, a mechanism (including the reduction mechanism 75) that is mechanically connected to the rotating shaft 77 of the motor 70 and transmits the rotational force of the rotating shaft 77 to the tip connection part 30. In this first embodiment, the moment of inertia of the tip connection part 30 alone is close to or approximately equal to the moment of inertia of the entire driven body.

[0074] (1-3) Electrical configuration of the cleaning device 14, there is shown an electrical configuration of the cleaning device 1. The cleaning device 1 includes a motor 70, a speed reduction mechanism 75, a tip connector 30, and a position sensor 65.

[0075] The motor 70 has three terminals 70a, 70b, and 70c. These three terminals 70a, 70b, and 70c are connected to three-phase windings in the motor 70. The motor 70 receives power via these three terminals 70a, 70b, and 70c.

[0076] The position sensor 65 includes three Hall sensors. The three Hall sensors are arranged corresponding to the three-phase windings of the motor 70. The three Hall sensors output position signals to the control circuit 60 in sequence each time the rotor of the motor 70 rotates by an electrical angle of 60 degrees. Note that in another embodiment, the motor 70 may be a brushed motor. In this case, the cleaning device 1 does not need to include the position sensor 65.

[0077] The cleaning device 1 further includes a controller 50. The controller 50 includes a power supply control circuit 52, a regulator 53, a control circuit 60, a first data communication unit 61, a second data communication unit 62, a gate circuit 55, an inverter circuit 56, a cutoff switch 59, a battery voltage detection unit 63, a current detection circuit 57, and a temperature detection circuit 58.

[0078] The power supply control circuit 52 is connected to the positive electrode of the battery pack 40, and controls the regulator 53 based on the power supply control signal and the main power supply signal. The power supply control signal is output from the battery pack 40, and indicates on or off. The on state of the power supply control signal corresponds to the remaining capacity of the battery pack 40 being equal to or greater than a predetermined amount, and the off state of the power supply control signal corresponds to the remaining capacity of the battery pack 40 being less than the predetermined amount. When the power supply control signal is on and the main power supply is on, the power supply control circuit 52 causes the regulator 53 to generate power to be supplied to each circuit of the controller 50. When the power supply control signal is off or the main power supply is off, the power supply control circuit 52 stops the regulator 53.

[0079] The inverter circuit 56 is connected to the positive electrode of the battery pack 40 via a cutoff switch 59. The inverter circuit 56 is a full-bridge circuit having three low-side switching elements and three high-side switching elements. The switching elements are, for example, MOSFETs. The cutoff switch 59 is a switching element such as a MOSFET.

[0080] The gate circuit 55 controls the on / off of each switching element of the inverter circuit 56 based on a motor control signal input from the control circuit 60. The inverter circuit 56 applies a voltage corresponding to the on / off of each switching element to a three-phase winding of the motor 70. The gate circuit 55 also controls the on / off of a cutoff switch 59 based on a switch control signal input from the control circuit 60. When the cutoff switch 59 is on, the inverter circuit 56 is conductive to the battery pack 40 and receives power from the battery pack 40. When the cutoff switch 59 is off, the electrical connection between the inverter circuit 56 and the battery pack 40 is cut off.

[0081] The battery voltage detection unit 63 detects the battery voltage value, and outputs the detected battery voltage value to the control circuit 60. The battery voltage value corresponds to the magnitude of the output voltage of the battery pack 40.

[0082] The current detection circuit 57 detects the battery current value, and outputs the detected battery current value to the control circuit 60. The battery current value corresponds to the magnitude of the current flowing from the battery pack 40 to the motor 70.

[0083] The temperature detection circuit 58 detects the circuit temperature of the controller 50 and outputs the detected circuit temperature to the control circuit 60 . The control circuit 60 of the first embodiment includes a microcomputer including a CPU 60a and a memory 60b. The memory 60b includes semiconductor memories such as ROM, RAM, NVRAM, and flash memory. The control circuit 60 (more specifically, the CPU 60a) executes programs stored in the memory 60b to realize various functions. The control circuit 60 also stores temporary data generated according to the various functions in the memory 60b.

[0084] Some or all of the various functions realized by the control circuit 60 may be achieved by execution of a program (i.e., by software processing), or may be achieved by one or more pieces of hardware. For example, instead of or in addition to a microcomputer, the control circuit 60 may include a logic circuit including a plurality of electronic components, an application specific integrated circuit such as an ASIC and / or an ASSP, or a programmable logic device such as an FPGA capable of constructing any logic circuit.

[0085] The control circuit 60 performs serial communication with the battery pack 40 via the first data communication unit 61 and receives battery information. The battery information includes identification data such as whether the battery pack 40 is in a dischargeable state or not, and the model number of the battery pack 40. The control circuit 60 receives a discharge permission signal or a discharge prohibition signal from the battery pack 40 via the second data communication unit 62. The discharge permission signal is transmitted from the battery pack 40 when the battery pack 40 is in a dischargeable state. The discharge prohibition signal is transmitted from the battery pack 40 when the battery pack 40 is in a non-dischargeable state.

[0086] The control circuit 60 generates a motor control signal and a switch control signal based on the main power signal, the removal mode signal, the trigger signal, the circuit temperature, the battery voltage value, the battery current value, the position signal, the battery information, and the discharge permission signal or the discharge prohibition signal. The control circuit 60 outputs the generated motor control signal and switch control signal to the gate circuit 55. The motor control signal includes a pulse width modulation (PWM) signal. The control circuit 60 also controls the LED of the speed display unit 151 based on the main power signal and the removal mode signal.

[0087] (1-4) Control circuit processing (1-4-1) Main processing The main processing executed by the control circuit 60 (specifically, the CPU 60a) will be described with reference to the flowchart of Fig. 15. The control circuit 60 repeatedly executes this processing at a predetermined control period.

[0088] In S10, it is determined whether a control period has elapsed since the start of the current processing cycle. The control period is set in advance. If it is determined that the control period has elapsed (S10: YES), the process proceeds to S20, and if it is determined that the control period has not elapsed (S10: NO), the process of S10 is repeatedly executed.

[0089] In S20, a switch operation detection process is executed to detect user operations of the main power / speed mode changeover switch 153, the removal mode switch 154, and the trigger 14. Then, the process proceeds to S30. The switch operation detection process will be described in detail later.

[0090] In S30, an AD conversion process is executed to convert the analog values ​​of the circuit temperature, the battery voltage value, and the battery current value input to the control circuit 60 into digital values. After that, the process proceeds to S40.

[0091] In S40, an error detection process is executed. More specifically, the occurrence of an error that requires protection of the cleaning device 1 or the battery pack 40 is detected based on the battery current value, battery voltage value, circuit temperature, rotation speed of the motor 70, battery information, etc. 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, an overspeed 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 process proceeds to S50.

[0092] In S50, a motor control process is executed to control the driving of the motor 70. Then, the process proceeds to S60. The motor control process will be described in detail later. In S60, a display process is executed. More specifically, the LED of the speed display unit 151 is turned on, blinked, or turned off based on the set speed mode and rotation direction. Also, if any error is detected in the process of S40, the LED of the error display unit 152 is turned on. Then, the process proceeds to S70.

[0093] In S70, a power management process is executed to turn the main power state on or off. The power management process will be described in detail later. (1-4-2) Interrupt processing The hall sensor interrupt process executed by the control circuit 60 will be described with reference to the flowchart of Fig. 16. When a position signal is input from any of the hall sensors included in the position sensor 65, the control circuit 60 executes this process by interrupt.

[0094] In the Hall sensor interrupt process, the control circuit 60 executes an inverter control process in S80. Specifically, it turns on or off six switching elements of the inverter circuit 56. The inverter control process will be described in detail later.

[0095] (1-4-3) Switch operation detection process The switch operation detection process executed by the control circuit 60 in S20 of the main process will be described with reference to the flowchart of FIG.

[0096] In S100, the states of various switches are obtained. That is, a main power signal is obtained from the main power / speed mode changeover switch 153, and a removal mode signal is obtained from the removal mode switch 154. Furthermore, a trigger signal is obtained from the trigger 14. After that, the process proceeds to S110.

[0097] In S110, a filter process is applied to various signals obtained from various switches, and if the on state continues for a certain period of time or more, the signal is detected as on, and if the off state continues for a certain period of time or more, the signal is detected as off. In other words, no instantaneous signal changes are detected. Then, the process proceeds to S120.

[0098] In S120, a change flag corresponding to the state change of various switches is turned on. More specifically, if the main power signal changes from on to off or off to on, the main power change flag is turned on. If the removal mode signal changes from on to off or off to on, the removal mode change flag is turned on. If the trigger signal changes from on to off or off to on, the trigger change flag is turned on. Then, the process proceeds to S130.

[0099] In S130, the time that each switch continues to be in the ON state or the time that each switch continues to be in the OFF state is measured. (1-4-4) Power management processing The power management process executed by the control circuit 60 in S70 of the main process will be described with reference to the flowchart of FIG.

[0100] In S200, it is determined whether the current main power state is off. If it is determined that the current main power state is on (S200: NO), the process proceeds to S210, and if it is determined that the current main power state is off (S200: YES), the process proceeds to S220.

[0101] In S210, a determination is made as to whether the main power state is off, and whether the main power state is to be switched from on to off or maintained on, and then this process ends. The details of the determination as to whether the main power state is off will be described later.

[0102] In S220, a main power state ON determination is performed to determine whether the main power state is switched from OFF to ON or maintained OFF. Specifically, if the main power change flag is ON, the main power state is switched from OFF to ON. If the main power change flag is OFF, the main power state is maintained OFF. Then, this process is terminated.

[0103] (1-4-5) Main power off detection process The main power supply OFF state determination process executed by the control circuit 60 in S210 of the power supply management process will be described with reference to the flowchart of FIG.

[0104] In S230, a process for determining whether the main power supply state is OFF due to a switch operation is executed. Specifically, if the main power supply change flag is ON, the main power supply state is switched from ON to OFF. If the main power supply change flag is OFF, the main power supply state is maintained ON. Then, the process proceeds to S240.

[0105] In S240, the automatic off determination process of the main power supply state is executed. Specifically, even if the main power supply change flag is off, it is determined whether to switch the main power supply state from on to off in order to save power, and this process is terminated. The details of the automatic off determination process of the main power supply state will be described later.

[0106] (1-4-6) Automatic main power off determination process The automatic off-determination process of the main power supply state executed by the control circuit 60 in S240 of the off-determination process of the main power supply state will be described with reference to the flowchart of FIG.

[0107] In S250, it is determined whether any of the switches has been operated by the user. That is, it is determined whether any of the main power change flag, the removal mode change flag, and the trigger change flag is in the ON state. If it is determined that at least one change flag is in the ON state (S250: YES), the process proceeds to S320, and if it is determined that all change flags are in the OFF state (S250: NO), the process proceeds to S260.

[0108] In S260, the main power on timer is incremented, and the process proceeds to S270. The main power on timer corresponds to the time during which the user has not operated the cleaning device 1 and the main power has been on.

[0109] In S270, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is not set to ON (S270: NO), the process proceeds to S280. If it is determined that the removal mode is set to ON (S270: YES), the process proceeds to S300.

[0110] In S280, it is determined whether the value of the main power on timer is equal to or greater than a first threshold value. The first threshold value is several minutes, for example, 5 minutes. A user may interrupt work using the cleaning device 1 with the main power on to perform another task, such as watering. In this case, if the user resumes work using the cleaning device 1 and the main power is off, the user may feel annoyed. On the other hand, if the user forgets to turn off the main power and stores the cleaning device 1, power from the battery pack 40 will be wasted unless the main power is turned off.

[0111] Therefore, the control circuit 60 judges whether the state where the user is not operating the cleaning device 1 is an interruption of work, and if it is determined that the state is not an interruption of work, it turns off the main power. The first threshold is a threshold for judging whether the state where the cleaning device 1 is not being operated is an interruption of work. If it is determined that the value of the main power on timer is equal to or greater than the first threshold (S280: YES), the process proceeds to S290, and if it is determined that the value of the main power on timer is less than the first threshold (S280: NO), this process ends.

[0112] In S290, if the state where the user has not operated the cleaning device 1 continues for more than the first threshold, it is determined that the current state is not an interruption of work, and the main power is turned off. After that, this process ends.

[0113] In S300, it is determined whether the value of the main power on timer is equal to or greater than the second threshold. The second threshold is a value smaller than the first threshold, for example, 1 minute. Normally, the user does not set the removal mode to on except when removing the tip attachment 20. Therefore, when the removal mode is set to on and the user is not operating the cleaning device 1, it is not necessary to determine whether the current state is an interruption of work, and the main power can be immediately turned off.

[0114] If it is determined that the value of the main power on timer is greater than or equal to the second threshold (S300: YES), proceed to processing at S310; if it is determined that the value of the main power on timer is less than the second threshold (S300: NO), terminate this processing.

[0115] In S310, the main power supply state is turned off, and this process ends. In S320, the main power on timer is cleared in response to the user operating the cleaning device 1. In other words, the value of the main power on timer is reset to zero. After that, this process ends.

[0116] (1-4-7) Motor control processing The motor control process executed by the control circuit 60 at S50 of the main process will be described with reference to the flowchart of FIG.

[0117] In S400, a speed mode setting process is executed to set the speed mode to any one of the high speed mode, the medium speed mode, and the low speed mode, and the process proceeds to S410. The speed mode setting process will be described in detail later.

[0118] In S410, a removal mode setting process is executed to set the removal mode to ON or OFF, and the process proceeds to S420. The removal mode is a mode for removing the tip attachment 20. When the removal mode is set to ON, the control circuit 60 performs control for removing the tip attachment 20, that is, control for generating the release moment described above in the tip attachment 20. The basic mode described above corresponds to a state in which the removal mode is set to OFF. The removal mode setting process will be described in detail later.

[0119] In the first embodiment, the operation mode of the cleaning device 1 is set to a removal mode or a basic mode. The basic mode corresponds to a state in which the removal mode is set to off, and the removal mode corresponds to a state in which the removal mode is set to on. Furthermore, in the first embodiment, in the basic mode, the motor 70 is controlled in one of a plurality of control modes. In the first embodiment, the plurality of control modes include a drive mode, a stop mode, a first brake mode, and a second brake mode (see FIG. 32).

[0120] In S420, a state transition process is executed to set the control mode of the motor 70 to the drive mode, the stop mode, the first brake mode or the second brake mode, and the process ends. The state transition process will be described in detail later.

[0121] (1-4-8) Speed ​​mode setting process The speed mode setting process executed by the control circuit 60 at S400 of the motor control process will now be described with reference to the flowchart of FIG.

[0122] In S430, it is determined whether the main power supply state is off or on. If it is determined that the main power supply state is on (S430: YES), the process proceeds to S440. If it is determined that the main power supply state is off (S430: NO), the process proceeds to S480.

[0123] In S440, it is determined whether the main power / speed mode changeover switch 153 has changed from on to off. In other words, it is determined whether the user has released the main power / speed mode changeover switch 153. In particular, it is determined whether the main power / speed mode changeover switch 153 has just been changed from on to off. If it is determined in S440 that the main power / speed mode changeover switch 153 has just been changed from on to off (S440: YES), the process proceeds to S450. If it is determined in S440 that the main power / speed mode changeover switch 153 has not just been changed from on to off (S440: NO), this process ends.

[0124] In S450, it is determined whether the main power / speed mode changeover switch 153 has been short-pressed. Specifically, it is determined whether the main power / speed mode changeover switch 153 has been short-pressed based on the duration of the on state of the main power / speed mode changeover switch 153 measured in S130. If it is determined that the main power / speed mode changeover switch 153 has been short-pressed (S450: YES), the process proceeds to S460. If it is determined that the main power / speed mode changeover switch 153 has not been short-pressed (S450: NO), this process ends.

[0125] In S460, the currently set speed mode is changed to the next speed mode, and the process proceeds to S470. In S470, the speed mode changed in S460 is stored in the memory 60b, and this process ends.

[0126] In S480, the speed mode stored in the memory 60b is set as the speed mode used to control the motor 70, and this process ends. (1-4-9) Removal mode setting process The removal mode setting process executed by the control circuit 60 at S410 of the motor control process will be described with reference to the flowcharts of FIGS. 23A to 23C.

[0127] First, in the processes of S500 to S560, a process of setting the removal mode switching request to ON or OFF is executed. In S500, it is determined whether the main power supply state is on. If it is determined that the main power supply state is on (S500: YES), the process proceeds to S510, and if it is determined that the main power supply state is off (S500: NO), the process proceeds to S540.

[0128] In S510, it is determined based on the removal mode change flag whether the removal mode switch 154 has changed from off to on. If it is determined that the removal mode switch 154 has changed from off to on (S510: YES), the process proceeds to S520, and if it is determined that the removal mode switch 154 remains off (S510: NO), the process proceeds to S570.

[0129] In S520, it is determined whether the protection of the cleaning device 1 or the battery pack 40 is operating. That is, in S40, it is determined whether any error has been detected. If it is determined that the protection of the cleaning device 1 or the battery pack 40 is operating (S520: YES), the process proceeds to S570. If it is determined that the protection of the cleaning device 1 or the battery pack 40 is not operating (S520: NO), the process proceeds to S530.

[0130] In S530, the removal mode switching request is turned on, and the process proceeds to S570. In S540, since the main power supply state is OFF, the motor stop request is turned OFF, and the process proceeds to S550.

[0131] In S550, the detachment mode is set to OFF so that the next time the user uses the cleaning device 1, operation will start in forward rotation, and the process proceeds to S560. In S560, the removal mode switching request is turned off, and the process proceeds to S570.

[0132] Next, in S570 to S610, a removal mode switching process is executed based on a removal mode switching request. In S570, it is determined whether the removal mode switching request is ON. If it is determined that the removal mode switching request is ON (S570: YES), the process proceeds to S580, and if it is determined that the removal mode switching request is OFF (S570: NO), the process proceeds to S620.

[0133] In S580, it is determined whether the rotation speed of the motor 70 is less than the stop determination threshold. For safety reasons, the rotation direction is not changed while the motor 70 is rotating. In S580, it is determined whether the motor 70 is in a state where it can be considered to be stopped. The stop determination threshold is small enough that the motor 70 can be considered to be stopped. If it is determined that the rotation speed is less than the stop determination threshold (S580: YES), the process proceeds to S590. If it is determined that the rotation speed is equal to or greater than the stop determination threshold (S580: NO), the rotation direction is not changed and the process proceeds to S620.

[0134] In S590, it is determined whether the trigger 14 is off (i.e., the trigger signal is off). If it is determined that the trigger 14 is off (S590: YES), the process proceeds to S600, and if it is determined that the trigger 14 is on (i.e., the trigger signal is on) (S590: NO), the process proceeds to S620.

[0135] In S600, the removal mode is switched to a state different from the currently set state. That is, if the current removal mode is set to OFF, the removal mode is switched to ON. If the current removal mode is set to ON, the removal mode is switched to OFF. Then, the process proceeds to S610.

[0136] In S610, since the removal mode switching has been completed, the removal mode switching request is turned off and the process proceeds to S620. Next, in S620 to S680, the process of setting the motor stop request to ON or OFF is executed.

[0137] In S620, it is determined whether the motor stop request is OFF. If it is determined that the motor stop request is OFF (S620: YES), the process proceeds to S630, and if it is determined that the motor stop request is ON (S620: NO), the process proceeds to S660.

[0138] In S630, it is determined whether the removal mode switching request is ON. If it is determined that the removal mode switching request is ON (S630: YES), the process proceeds to S640, and if it is determined that the removal mode switching request is OFF (S630: NO), the process proceeds to S690.

[0139] In S640, it is determined whether the rotation speed is equal to or greater than the stoppage determination threshold. If it is determined that the rotation speed is equal to or greater than the stoppage determination threshold (S640: YES), the process proceeds to S650. If it is determined that the rotation speed is less than the stoppage determination threshold (S640: NO), the process proceeds to S690.

[0140] In S650, the motor stop request is turned on. As a result, in the state transition process described below, the stop process of the motor 70 is executed, and the rotation speed becomes less than the stop determination threshold. In addition, in S600, the rotation direction is switched. After that, the process proceeds to S690.

[0141] In S660, it is determined whether the rotation speed is less than the stop determination threshold. If it is determined that the rotation speed is less than the stop determination threshold (S660: YES), the process proceeds to S670, and if it is determined that the rotation speed is equal to or greater than the stop determination threshold (S660: NO), the process proceeds to S690.

[0142] In S670, it is determined whether the trigger 14 is off. If it is determined that the trigger 14 is off (S670: YES), the process proceeds to S680, and if it is determined that the trigger 14 is on (S670: NO), the process proceeds to S690.

[0143] In S680, since the motor 70 has stopped and the user has not requested restarting the motor 70, the motor stop request is turned off and the process proceeds to S690. Next, in S690 to S740, if the conditions for applying the brakes for removal are met, a process of setting a motor stop request to ON is executed.

[0144] In S690, the control circuit 60 executes a rotation speed threshold calculation process. In the rotation speed threshold calculation process, a first rotation speed threshold is calculated. The first rotation speed threshold corresponds to the rotation speed of the motor 70 required to detach the end attachment 20.

[0145] In the first embodiment, the motor 70 is braked during rotation to rapidly decelerate it, thereby generating a release moment in the tip attachment 20 (i.e., generating the release force described above) and removing the tip attachment 20. In order to generate a release moment in the tip attachment 20 by braking in this way, it is necessary to apply the brake when the rotation speed of the motor 70 has reached a certain level in order to generate the necessary deceleration.

[0146] "A certain level" depends mainly on the moment of inertia of the tip attachment 20. More specifically, "a certain level" depends on the difference between the moment of inertia of the tip attachment 20 and the moment of inertia of the tip connection part 30, in other words, the relative moment of inertia of the tip attachment 20 based on the moment of inertia of the tip connection part 30. In the following description, when the term "moment of inertia" is used simply, it means the relative moment of inertia of the tip attachment 20 described above, unless otherwise specified.

[0147] The smaller the moment of inertia, the greater the braking torque required to detach the tip attachment 20. In other words, the smaller the moment of inertia, the higher the "certain level" of rotational speed required when braking begins. This "certain level" of rotational speed corresponds to the first rotational speed threshold.

[0148] In the first embodiment, a target rotation speed is set when the motor 70 is driven. When the operation mode is set to the basic mode (i.e., when the removal mode is set to off), the target rotation speed is set according to the set speed mode. Then, power according to the target rotation speed is supplied to the motor 70 to drive the motor 70. As a result, the actual rotation speed of the motor 70 increases (i.e., accelerates) toward the target rotation speed after starting to drive, and reaches the target rotation speed or its vicinity.

[0149] As illustrated in FIG. 25, in the first embodiment, the target rotation speed in the basic mode gradually increases from the start of driving to the specified maximum speed. In detail, it is the specified maximum speed that differs depending on the speed mode. The specified maximum speed in the high speed mode is the highest, and the specified maximum speed in the low speed mode is the lowest. The target rotation speed for each speed mode may be stored in advance in the memory 60b, for example. The target rotation speed may be set to the specified maximum speed from the start of driving. However, in the first embodiment, the target rotation speed is gradually increased from the start of driving to the specified maximum speed.

[0150] The target rotation speed illustrated in FIG. 25 is the target rotation speed in the basic mode in which the removal mode is set to OFF. The target rotation speed in the removal mode (specifically, the specified maximum speed) may be set in any manner. For example, the target rotation speed in the removal mode may be (i) higher than the specified maximum speed in the high speed mode, (ii) the same as the specified maximum speed in any speed mode, (iii) a predetermined speed between the specified maximum speed in the low speed mode and the specified maximum speed in the high speed mode, or (iv) lower than the specified maximum speed in the low speed mode.

[0151] For example, the speed mode setting may be enabled in the removal mode as well. In this case, the target rotation speed in the removal mode may be higher than in the basic mode, may be the same as in the basic mode, or may be lower than in the basic mode. Also, in the removal mode, the target rotation speed may be gradually increased toward the specified maximum speed.

[0152] In the removal mode, the higher the target rotation speed, the longer the rapid deceleration period that can be generated during removal, and this allows a large counter torque (and therefore a release moment) to be generated for a long period in the tip attachment 20. Therefore, it can be said that the higher the target rotation speed, the easier it is to remove the tip attachment 20.

[0153] However, in this first embodiment, what is most important for removing the tip attachment 20 is the deceleration at which a release moment can be generated, rather than the target rotation speed, because no matter how high the target rotation speed is, if the deceleration is low, the release moment cannot be generated.

[0154] Therefore, it is necessary to generate at least a sufficient deceleration in order to reliably remove the tip attachment 20. More preferably, it is more effective to appropriately set the target rotation speed in order to ensure a necessary and sufficient deceleration time.

[0155] In the first embodiment, in any speed mode, the specified maximum speed is set to be at least higher than the rotation speed of the "certain level". Note that in any speed mode (e.g., low speed mode), the specified maximum speed may be set to be lower than the "certain level".

[0156] The first rotational speed threshold may be, for example, a fixed value. That is, in S690, it may be a predetermined value. This fixed value may be theoretically derived based on, for example, the design moment of inertia.

[0157] Alternatively, the first rotational speed threshold may be dynamically calculated based on, for example, an estimated value of the moment of inertia. That is, the end attachment 20 may be actually operated, the moment of inertia may be estimated based on various parameters obtained during the operation, and the first rotational speed threshold may be calculated based on the estimated moment of inertia (hereinafter referred to as the "estimated moment of inertia"). Specifically, the first rotational speed threshold may be calculated so that the smaller the estimated moment of inertia, the higher the first rotational speed threshold.

[0158] S690 in FIG. 23C shows an example of calculating the first rotation speed threshold value based on the estimated moment of inertia. That is, in S691, it is determined whether the estimation of the moment of inertia is completed. As described later, if the estimation of the moment of inertia is completed, the estimation state is set to "completed", and if the estimation is not completed, the estimation state is set to "incomplete". Therefore, it is possible to determine whether the estimation of the moment of inertia is completed based on the set estimation state. Details of the process of estimating the moment of inertia will be described later.

[0159] If the estimation of the moment of inertia is not completed (S691: NO), the first rotation speed threshold is set as the reference threshold in S694, and the process proceeds to S700. In the first embodiment, the reference threshold is the fixed value described above.

[0160] If the estimation of the moment of inertia is completed (S691: YES), the ratio [%] of the estimated moment of inertia to the reference is calculated in S692. The ratio to the reference is the ratio between the estimated moment of inertia and the reference moment of inertia, and is obtained, for example, by calculating "estimated moment of inertia / reference moment of inertia x 100". The reference moment of inertia corresponds to, for example, the design moment of inertia described above.

[0161] An upper limit and / or a lower limit may be set for the ratio to the reference. For example, if the calculated ratio to the reference exceeds an upper limit (e.g., 150%), it may be uniformly treated as 150%. Also, if the calculated ratio to the reference is less than a lower limit (e.g., 50%), it may be uniformly treated as 50%.

[0162] In S693, the first rotation speed threshold is calculated based on the ratio to the reference calculated in S692. Specifically, the first rotation speed threshold may be calculated by, for example, calculating "reference threshold / ratio to the reference [%] x 100". The larger the estimated moment of inertia is, the larger the ratio to the reference becomes, and the lower the first rotation speed threshold becomes. After the process of S693, the process proceeds to S700.

[0163] In S700, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S700: YES), the process proceeds to S710, and if it is determined that the removal mode is set to OFF (S700: NO), the process ends.

[0164] In S710, it is determined whether the control mode of the motor 70 is set to the drive mode. If it is determined that the control mode is set to the drive mode (S710: YES), the process proceeds to S720, and if it is determined that the control mode is not set to the drive mode (S710: NO), this process ends.

[0165] In S720, it is determined whether the actual rotation speed of the motor 70 is equal to or greater than the first rotation speed threshold calculated in S690. If it is determined that the actual rotation speed is equal to or greater than the first rotation speed threshold (S720: YES), the process proceeds to S730, and if it is determined that the actual rotation speed is less than the first rotation speed threshold (S720: NO), the process ends.

[0166] In S730, the motor stop request is turned on, and the process proceeds to S740. In S740, the automatic off determination process of the removal mode is executed. Specifically, it is determined whether it can be inferred that the tip attachment 20 has been detached from the cleaning device 1, and if it can be inferred that the tip attachment 20 has been detached from the cleaning device 1, the removal mode is automatically changed to off without the user operating the removal mode switch 154. The automatic off determination process of the removal mode will be described in detail later. Then, this process is terminated.

[0167] In FIG. 23C, the timing to apply the brakes (i.e., the timing to set the motor stop request to ON) is determined based on the first rotation speed threshold and the actual rotation speed of the motor 70. However, the timing to apply the brakes may be determined in any manner. For example, it may be determined based on the elapsed time since the motor 70 starts to drive. FIG. 24 shows an example in which the timing to apply the brakes is determined based on the elapsed time. FIG. 24 is a modified example of FIG. 23C. In other words, the processing of FIG. 24 may be executed instead of the processing of FIG. 23C.

[0168] When the control circuit 60 proceeds to the processing of FIG. 24, in S750, it sets the automatic stop time to a specified time. The specified time corresponds to an estimate of the time required for the actual rotation speed to reach the aforementioned "certain level" after the motor 70 starts to be driven. The specified time may be estimated in any way. For example, the specified time may be estimated based on the moment of inertia (i.e., the estimated moment of inertia or the designed moment of inertia). The subsequent processing of S700 and S710 is similar to that of FIG. 23C.

[0169] In the next S760, it is determined whether the automatic stop time (i.e., the specified time) has elapsed since the motor drive started. If it is determined that the automatic stop time has elapsed since the motor drive started (S760: YES), the process proceeds to S730, and if it is determined that the automatic stop time has not elapsed since the motor drive started (S760: NO), this process ends. The processes of S730 and S740 are the same as those in FIG. 23C.

[0170] Note that the brake timing determination based on the actual rotation speed shown in Fig. 23C and the brake timing determination based on the elapsed time shown in Fig. 24 may be used together. For example, when the actual rotation speed is equal to or greater than the first rotation speed threshold or the automatic stop time has elapsed since the motor drive started, the motor stop request may be set to ON. Also, for example, when the actual rotation speed is equal to or greater than the first rotation speed threshold and the automatic stop time has elapsed since the motor drive started, the motor stop request may be set to ON.

[0171] (1-4-10) Automatic power-off judgment process for removal mode Next, the automatic OFF determination process of the removal mode in S740 (see FIG. 23C) will be described in detail with reference to the flowchart of FIG. 26. This process automatically sets the removal mode to OFF when a situation arises in which the removal mode should be set to OFF after the removal mode is set to ON. In S780, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S780: YES), the process proceeds to S790. If it is determined that the removal mode is set to OFF (S780: NO), the process proceeds to S810.

[0172] In S790, it is determined whether the control mode has been switched to the stop mode in the current control cycle. If the control mode has been switched to the stop mode, the process proceeds to S800. If the control mode has not been switched to the stop mode (i.e., if the control mode has been set to any mode other than the stop mode), the process proceeds to S820.

[0173] In S800, the currently calculated number of times the motor has been driven in the removal mode is incremented by "1", and the process proceeds to S820. In other words, the number of times the motor has been driven is updated. The number of times the motor has been driven corresponds to the time from when the motor 70 starts to rotate until when it stops.

[0174] In S810, the number of times of driving in the removal mode is set to "0 times", and the process proceeds to S820. In other words, in S810, the number of times of driving is reset. In S820, it is determined whether the currently calculated number of times of driving in the removal mode is equal to or greater than a predetermined number of times. In other words, this determination is a determination as to whether the tip attachment 20 has been detached from the tip connection part 30. When the number of times of driving in the removal mode reaches the predetermined number of times, it can be estimated that the engagement between the first claws 33, 34, 35 and the second claws 23, 24, 25 has been released and the tip attachment 20 has been detached from the tip connection part 30. The predetermined number of times may be determined in any manner. The predetermined number of times may be, for example, one time or two or more times.

[0175] If it is determined that the number of times the device has been driven in the removal mode is equal to or greater than the predetermined number (S820: YES), the process proceeds to S830. If it is determined that the number of times the device has been driven in the removal mode is less than the predetermined number (S820: NO), the process ends.

[0176] In S830, it is determined whether the motor 70 has completely stopped. This determination can be made, for example, based on the position signals from the three Hall sensors. For example, when none of the three position signals has changed for a predetermined period of time or more, it can be determined that the motor 70 has completely stopped.

[0177] If the motor 70 has completely stopped (S830: YES), the process proceeds to S840, and if the motor 70 has not completely stopped (S830: NO), this process ends. In S840, the removal mode is set to OFF, and then the process ends.

[0178] (1-4-11) State transition processing The state transition process of S420 (see FIG. 21) will be described in detail with reference to the flowchart of FIG.

[0179] 27, in S860, the moment of inertia estimation process is executed. Specifically, the moment of inertia described above is estimated. The process of S860 will be described in detail later. In S870, it is determined whether the main power supply state is ON. If it is determined that the main power supply state is ON (S870: YES), the process proceeds to S880, and if it is determined that the main power supply state is OFF (S870: NO), the process proceeds to S950.

[0180] In S880, it is determined whether the protection of the cleaning device 1 or the battery pack 40 is operating. If it is determined that the protection of the cleaning device 1 or the battery pack 40 is operating (S880: YES), the process proceeds to S950. If it is determined that the protection of the cleaning device 1 or the battery pack 40 is not operating (S880: NO), the process proceeds to S890.

[0181] In S890, it is determined whether the trigger 14 is on. If it is determined that the trigger 14 is on (S890: YES), the process proceeds to S900, and if it is determined that the trigger 14 is off (S890: NO), the process proceeds to S940.

[0182] In S900, it is determined whether the motor stop request is OFF. If it is determined that the motor stop request is OFF (S900: YES), the process proceeds to S910, and if it is determined that the motor stop request is ON (S900: NO), the process proceeds to S940.

[0183] In S910, the control mode of the motor 70 is set to the drive mode, and the process proceeds to S920. In S920, the free-run timer is reset. The free-run timer measures the time during which the motor 70 is free-running. "Free-running" means that the motor 70 is rotated by inertia without applying a brake to the motor 70. During free-running, the control circuit 60 stops controlling the inverter circuit 56. Therefore, during free-running, all six switching elements in the inverter circuit 56 are turned off.

[0184] In S930, a first output calculation process is executed. In the first output calculation process, an output duty ratio in the drive mode is calculated. The output duty ratio is the duty ratio of the PWM signal described above. The first output calculation process will be described in detail later.

[0185] In S940, a second output calculation process is executed. In the second output calculation process, a control mode for stopping the motor 70 is set. Specifically, the control mode is set to the first brake mode, the second brake mode, or the stop mode. The second output calculation process will be described in detail later.

[0186] In S950, the control mode of the motor 70 is set to the stop mode, and the process proceeds to S960. In S960, since the control mode is the stop mode, a process for stopping the motor 70 is executed, and the process proceeds to S970.

[0187] In S970, the output duty ratio is initialized (for example, set to 0), and this process ends. (1-4-12) First output calculation process Next, the first output calculation process of S930 (see FIG. 27) will be described in detail with reference to the flowchart of FIG.

[0188] In S105, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S105: YES), the process proceeds to S115. If it is determined that the removal mode is set to OFF (S105: NO), the process proceeds to S135.

[0189] In S115, a target rotation speed when the removal mode is set to ON is set. In S125, the output duty ratio of the PWM signal is calculated based on the target rotation speed set in S115. After that, this process ends. In S125, the output duty ratio may be calculated by proportional-integral control based on the difference between the target rotation speed and the actual rotation speed so that the difference becomes zero. In other words, speed feedback control may be performed. However, open control that does not refer to the actual rotation speed may also be performed. In that case, the output duty ratio may be determined according to the target rotation speed.

[0190] In S135, it is determined whether the estimation of the moment of inertia is complete. If the estimation of the moment of inertia is complete (S135: YES), the process proceeds to S145. If the estimation of the moment of inertia is not complete (S135: NO), the process proceeds to S165.

[0191] In S145, a target rotation speed is set according to the set speed mode. The target rotation speed is set in the basic mode, and is set according to the setting information shown in FIG.

[0192] In S155, the output duty ratio of the PWM signal is calculated based on the target rotation speed set in S145 in the same manner as in S125, after which the process ends. In S165, an estimation motor applied voltage is calculated. The estimation motor applied voltage is a constant voltage to be applied to the motor 70 in order to estimate the moment of inertia. In the first embodiment, the moment of inertia is estimated using a very short period of time immediately after the start of driving in the basic mode. During this short period of time, a constant estimation motor applied voltage is applied to the motor 70. Based on the operating state of the motor 70 at that time, the moment of inertia is estimated, as described below.

[0193] In S175, the output duty ratio of the PWM signal is calculated based on the estimation motor application voltage calculated in S165. After that, this process is terminated. That is, in S175, the output duty ratio is calculated so that the estimation motor application voltage is applied to the motor 70. Here, for example, a constant output duty ratio corresponding to the estimation motor application voltage may be calculated or set in advance. However, when the battery voltage fluctuates, the voltage actually applied to the motor 70 changes even if the output duty ratio is constant. Therefore, the output duty ratio may be calculated based on the battery voltage so that the voltage actually applied to the motor 70 is maintained at the estimation motor application voltage even if the battery voltage fluctuates. For example, the output duty ratio may be increased as the battery voltage decreases, so that a constant estimation motor application voltage is applied to the motor 70 regardless of the battery voltage.

[0194] (1-4-13) Second output calculation process Next, the second output calculation process of S940 (see FIG. 27) will be described in detail with reference to the flowchart of FIG.

[0195] In S205, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S205: YES), the process proceeds to S215. If it is determined that the removal mode is set to OFF (S205: NO), the process proceeds to S285.

[0196] In S215, the braking force for removing the tip attachment 20 is set. In other words, the braking force required to generate a release moment in the tip attachment 20 is set. Specifically, the braking force is set based on the estimated moment of inertia. In this first embodiment, the braking force is set between 0% and 100%. 0% corresponds to no braking. A braking force of 100% corresponds to the strongest braking of the motor 70. When the braking force is set to 100%, in this first embodiment, the motor 70 is braked by three-phase short circuit braking.

[0197] In S215, for example, the smaller the estimated moment of inertia, the larger the braking force is set to. Specifically, in S215, the braking force is set within a range in which the tip attachment 20 can be removed (for example, between 100% and 50%).

[0198] In addition, there may be cases where the moment of inertia has not yet been estimated at the time of S215. In such cases, the braking force may be set based on, for example, the design moment of inertia, or may be set in the same manner as in S226 described later.

[0199] In S225, a free run time is set according to the estimated moment of inertia. In the first embodiment, the motor 70 is made to free run before braking for removal is started. The time for which the motor 70 is made to free run is the free run time. For example, the free run time may be set so that it becomes shorter as the estimated moment of inertia becomes smaller. The free run time may be set within a range of 0.1 to 0.5 seconds, for example. After the process of S225, the process proceeds to S235.

[0200] In S285, the brake force during normal driving (i.e., during basic mode with the removal mode turned off) is set. Here, a predetermined brake force greater than 0% (e.g., 50%) may be set, or a brake force of 0% may be set. Setting a brake force of 0% means that the motor is stopped while rotating by inertia without applying the brakes.

[0201] In S295, a free run time is set. Then, the process proceeds to S235. The free run time set in S295 may be the same as or different from the free run time set in S225. For example, since the removal mode is set to OFF in S295, a time shorter than that in S225 (for example, 1 second) may be set.

[0202] In S235, the free-run timer is counted up. The free-run timer is a timing unit for measuring the time during which the free run is being performed. In S245, it is determined whether the current value (measured time) of the free-run timer is equal to or greater than the set free-run time. If the value of the free-run timer is equal to or greater than the free-run time (S245: YES), the process proceeds to S255. If the value of the free-run timer is less than the free-run time (S245: NO), the process proceeds to S275.

[0203] In S255, the control mode is set according to the set braking force. Specifically, when the braking force is equal to or greater than the first brake threshold, the control mode is set to the first brake mode, when the braking force is less than the first brake threshold and greater than the second brake threshold, the control mode is set to the second brake mode, and when the braking force is equal to or less than the second brake threshold, the control mode is set to the stop mode. The first and second brake thresholds may be determined in any manner. In the first embodiment, the first brake threshold is 100% and the second brake threshold is 0%.

[0204] In S265, the output duty ratio is initialized (for example, set to 0%), and this process ends. When the control mode is other than the drive mode, the motor 70 is braked or stopped by free running. Therefore, the output duty ratio is initialized.

[0205] In S275, the control mode is set to the stop mode, and then the process proceeds to S265. 27 to 29 have been described on the assumption that the moment of inertia is estimated. However, it is not essential to estimate the moment of inertia, and the configuration may be such that the moment of inertia is not estimated.

[0206] In this case, the process of S860 is omitted from FIG. In addition, S135, S165, and S175 are omitted from Fig. 28. In this case, if a negative determination is made in S105, the process proceeds to S145.

[0207] In addition, in FIG. 29, the processes of S226 and S227 are executed instead of the processes of S215 and S225. In S226, a predetermined braking force corresponding to the removal mode is set. The braking force set here may be any magnitude capable of generating a release moment. In the first embodiment, the braking force is set to, for example, 100% in S226. In other words, the maximum value within the range that can be set in S215 is set.

[0208] In S227, a predetermined free run time is set. In the first embodiment, the free run time is set to, for example, 0.1 seconds in S227. That is, the minimum value within the range that can be set in S225 is set.

[0209] In Fig. 27 and Fig. 29, the motor 70 is made to free run when the motor 70 is stopped. However, it is not essential to perform the free run, and the free run may be omitted. In this case, S920 is omitted from Fig. 27, and S225, S235, S245, S275, S295, and S227 are omitted from Fig. 29. Then, after S215, after S295, and after S226, the process proceeds to S255.

[0210] (1-4-14) Moment of inertia estimation process Next, the moment of inertia estimation process of S860 (see FIG. 27) will be described in detail with reference to the flowchart of FIG.

[0211] In S305, it is determined whether the main power state is set to ON. If the main power state is set to ON (S305: YES), the process proceeds to S315. If the main power state is set to OFF (S305: NO), the process proceeds to S365.

[0212] In S315, it is determined whether the removal mode has been switched from on to off at the current control timing. If the removal mode has not been switched from on to off, the process proceeds to S325. If the removal mode has been switched from on to off, the process proceeds to S365.

[0213] In S365, the estimation state of the moment of inertia is set to "incomplete". After that, this process ends. That is, in this first embodiment, the estimation of the moment of inertia is repeated every time the forward rotation of the motor 70 is started. Therefore, after the estimation of the moment of inertia is completed, if the motor is driven once in the removal mode and then the removal mode is released, the estimation state of the moment of inertia is changed to "incomplete" and the estimation is performed again.

[0214] In S325, it is determined whether the estimation of the moment of inertia is complete. If the estimation of the moment of inertia is complete (i.e., the estimation state is "completed"), this process ends. If the estimation of the moment of inertia is not complete, the process proceeds to S335.

[0215] In S335, it is determined whether a predetermined time has elapsed since the start of driving in the forward direction. If the predetermined time has elapsed since the start of driving in the forward direction, the process proceeds to S345. If the predetermined time has not yet elapsed since the start of driving in the forward direction, this process ends.

[0216] In S345, the moment of inertia is calculated (i.e., estimated) from the current actual rotation speed of the motor 70. After the start of normal rotation, a constant estimation motor applied voltage continues to be applied to the motor 70 until the estimation of the moment of inertia is completed (see S165 to S175 in FIG. 28). Therefore, the actual rotation speed after a predetermined time has elapsed since the start of normal rotation depends on the moment of inertia. For example, the larger the moment of inertia, the lower the actual rotation speed after the predetermined time has elapsed. Therefore, in S345, the moment of inertia is estimated based on the actual rotation speed so that the lower the actual rotation speed, the lower the moment of inertia. When the calculation (estimation) of the moment of inertia in S345 is completed, the process proceeds to S355.

[0217] In S355, the estimation state of the moment of inertia is set to "completed." Then, this process ends. (1-4-15) Inverter control processing The inverter control process at S80 (see FIG. 16) will be described in detail with reference to the flowchart of FIG.

[0218] In S405, the set control mode is acquired, and the process proceeds to S415. In S415, the calculated output duty ratio is acquired, and the process proceeds to S425. In S425, the rotor position is obtained based on the position signal output from the position sensor 65, and the process proceeds to S435.

[0219] In S435, the INV control process is executed, and the process ends. The details of the INV control process are shown in FIG. (1-4-16) INV control processing As shown in FIG. 32, in the INV control process, the currently set control mode is determined in S505.

[0220] If the current control mode is the first brake mode, the process proceeds to S515. In S515, a three-phase short circuit brake process is executed. That is, a motor control signal is output for turning on all three low-side switching elements in the inverter circuit 56. When the three low-side switching elements are turned on, the three terminals 70a, 70b, and 70c of the motor 70 are electrically short-circuited to each other. This applies a three-phase short circuit brake to the motor 70, and a strong braking force is applied to the motor 70. This causes the motor 70 to rapidly decelerate. After the process of S515, the process ends.

[0221] If the current control mode is the second brake mode in S505, the process proceeds to S525. In S525, parameters for two-phase short circuit braking are set. Specifically, the brake phase angle for two-phase energization is set according to the set brake force. Then, the process proceeds to S535. In S535, two-phase short circuit braking process is executed. That is, a motor control signal for turning on any two of the three low-side switching elements in the inverter circuit 56 is output. As a result, any two of the three terminals 70a, 70b, and 70c of the motor 70 are electrically short-circuited with each other. As a result, the two-phase short circuit brake is applied to the motor 70, and the motor 70 is decelerated. After the process of S535, the process ends.

[0222] If the current control mode is the stop mode in S505, the process proceeds to S545. In S545, a free-run stop process is executed. That is, the control of the inverter circuit 56 is stopped (i.e., all six switching elements are turned off) without braking the motor 70, and the motor 70 is stopped naturally. After the process of S545, the process ends.

[0223] If the current control mode is the drive mode in S505, the process proceeds to S555. In S555, the motor drive process is executed. Specifically, a motor control signal including a PWM signal is generated based on the control mode, output duty ratio, and position signal acquired in S405 to S425, and the motor control PWM signal is output to the gate circuit 55. This drives the motor 70. After the process of S555, the process ends.

[0224] (1-4-17) Correspondence of terms In the first embodiment, the tip attachment 20 corresponds to an example of a cleaning tool in the summary of the embodiments. The forward direction or forward rotation direction corresponds to an example of a first rotation direction in the summary of the embodiments. The reverse direction or reverse direction corresponds to an example of a second rotation direction in the summary of the embodiments. Each of the first claws 33, 34, 35 corresponds to an example of an engaging portion in the summary of the embodiments. Each of the second claws 23, 24, 25 corresponds to an example of an engaged portion in the summary of the embodiments. The basic mode corresponds to an example of a first mode in the summary of the embodiments. The removal mode corresponds to an example of a second mode in the summary of the embodiments. The removal mode switch 154 corresponds to an example of a switch in the summary of the embodiments. The combination of the gate circuit 55 and the inverter circuit 56 corresponds to an example of a drive circuit in the summary of the embodiments. The process for removing the tip attachment 20 (i.e., for decelerating the motor 70) in the main process, which is executed in the removal mode, corresponds to an example of a release control in the summary of the embodiments. The three-phase short circuit brake executed in the first brake mode corresponds to an example of a first brake in the summary of the embodiments. The two-phase short circuit brake executed in the second brake mode corresponds to an example of the second brake in the summary of the embodiments. The combination of the position sensor 65 and the control circuit 60 corresponds to an example of the speed detection unit in the summary of the embodiments. The automatic stop time corresponds to an example of the threshold time in the summary of the embodiments. The free run time set in S225 and S227 corresponds to an example of the first time in the summary of the embodiments. The free run time set in S295 corresponds to an example of the second time in the summary of the embodiments. Turning off the trigger 14 in the basic mode corresponds to an example of the first stop requirement in the summary of the embodiments.

[0225] [2. Second embodiment] A cleaning device of the second embodiment will be described. The cleaning device of the second embodiment is basically the same in structure as the cleaning device 1 of the first embodiment. The electrical configuration is also basically the same as that shown in FIG. 14. The cleaning device of the second embodiment differs from the cleaning device 1 of the first embodiment mainly in the processing executed by the control circuit 60.

[0226] The control circuit 60 of the second embodiment also basically executes the main processing of Fig. 15. However, the details thereof are partially different from those of the first embodiment. In the first embodiment, the tip attachment 20 was detached by suddenly decelerating the motor 70 during forward rotation. In contrast, in the second embodiment, the tip attachment 20 is detached by rotating the motor 70 in the reverse direction. In detail, when removing the tip attachment 20, the motor 70 is suddenly accelerated in the reverse direction from a stopped state. This sudden acceleration generates a release moment in the tip attachment 20, which allows the tip attachment 20 to be removed.

[0227] Hereinafter, various processes executed by the control circuit 60 of the second embodiment will be described, focusing on those that are basically different from the first embodiment. (2-1) Interrupt processing The Hall sensor interrupt process of the second embodiment will be described with reference to the flowchart of Fig. 33. The Hall sensor interrupt process of the second embodiment is different from the Hall sensor interrupt process of the first embodiment shown in Fig. 16 in that a reverse rotation angle calculation process of S90 is added. The reverse rotation angle calculation process of S90 is executed after the inverter control process of S80.

[0228] In the process of calculating the reverse rotation angle, the control circuit 60 calculates the reverse rotation angle θ of the tip connection part 30. The reverse rotation angle θ is the angle by which the tip connection part 30 rotates in the reverse direction. The process of calculating the reverse rotation angle will be described in detail later.

[0229] The processes in FIGS. 17 to 20 in the first embodiment are also executed in the second embodiment. (2-2) Motor control processing The motor control process of the second embodiment will be described with reference to the flowchart of Fig. 34. The motor control process is the process of S50 in the main process. The motor control process of the second embodiment differs from the motor control process of the first embodiment shown in Fig. 21 in that a rotation direction setting process of S411 is added.

[0230] The rotation direction setting process of S411 is executed after the removal mode setting process of S410. In the rotation direction setting process, the rotation direction of the motor 70 is set to forward or reverse. After the rotation direction setting process of S411 is executed, the process proceeds to S420. The rotation direction setting process will be described in detail later.

[0231] The speed mode setting process of FIG. 22 in the first embodiment is also executed in the second embodiment. (2-3) Removal mode setting process The removal mode setting process of S410 in the motor control process of Fig. 34 is largely similar to the removal mode setting process of the first embodiment shown in Fig. 23A to Fig. 23C. Specifically, the first part (Fig. 23A) and the second part (Fig. 23B) are executed in the same manner in the second embodiment. On the other hand, the third part is partially different from Fig. 23C.

[0232] In FIG. 23C of the first embodiment, the timing to apply the brakes (i.e., the timing to set the motor stop request to ON) is determined based on the rotation speed threshold and the actual rotation speed of the motor 70, or based on the elapsed time from the start of driving.

[0233] In contrast, in the second embodiment, it is determined whether or not the motor 70 should be automatically stopped in the removal mode. If it is determined that the motor should be automatically stopped, the motor stop request is set to ON. Specifically, the process shown in FIG. 35 is executed instead of FIG. 23C.

[0234] 35, the control circuit 60 executes a process of acquiring the reverse rotation angle of the tip connector 30 in S605, acquires the reverse rotation angle θ, and proceeds to the process of S615. The details of the process of acquiring the reverse rotation angle of the tip connector 30 will be described later.

[0235] In S615, automatic stop determination processing in the removal mode is executed, the automatic stop determination in the removal mode is set to ON or OFF, and the process proceeds to S625. The automatic stop determination processing in the removal mode will be described in detail later.

[0236] In S625, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S625: YES), the process proceeds to S635, and if it is determined that the removal mode is set to OFF (S625: NO), the process ends.

[0237] In S635, it is determined whether the control mode of the motor 70 is set to the drive mode. If it is determined that the control mode is set to the drive mode (S635: YES), the process proceeds to S645, and if it is determined that the control mode is not set to the drive mode (S635: NO), this process ends.

[0238] In S645, it is determined whether the automatic stop determination in the removal mode is set to ON based on the processing result of S615. If it is determined that the automatic stop determination in the removal mode is set to ON (S645: YES), the process proceeds to S655, and if it is determined that the automatic stop determination in the removal mode is set to OFF (S645: NO), this process ends.

[0239] In S655, the motor stop request is turned on, similar to S730 in the first embodiment. In the following S665, the automatic off determination process in the removal mode is executed, similar to S740 in the first embodiment. After that, this process is terminated.

[0240] (2-4) First example of the process for obtaining the reversal angle of the connection A first example of the process of acquiring the reverse rotation angle of the connection portion in S605 (see FIG. 35) will be described with reference to the flowchart in FIG.

[0241] In S705, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S705: YES), the process proceeds to S715. If it is determined that the removal mode is set to OFF (S705: NO), the process proceeds to S735.

[0242] In S715, the request to obtain the reverse rotation angle θ is turned on. This causes the reverse rotation angle θ to be calculated in the reverse rotation angle calculation process (see FIG. 45) described later. Then, the process proceeds to S725.

[0243] In S725, the reverse rotation angle θ calculated in the reverse rotation angle calculation process (see FIG. 45) is acquired, and this process ends. In S735, the request to obtain the reverse rotation angle θ is turned off, and the process proceeds to S745.

[0244] In S745, the reverse rotation angle θ is set to 0 degrees, and the process ends. (2-5) Second example of connection reversal angle acquisition process A second example of the process of acquiring the reverse rotation angle of the connection part in S605 (see FIG. 35) will be described with reference to the flowchart in FIG. 37. The second example illustrates the process when the motor 70 is a brushed motor. Note that when the motor 70 is a brushed motor, the control circuit 60 does not execute the process of calculating the reverse rotation angle in S90 in the Hall sensor interrupt process (see FIG. 33).

[0245] In S805, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S805: YES), the process proceeds to S815, and if it is determined that the removal mode is set to OFF (S805: NO), the process proceeds to S855.

[0246] In S815, the rotation speed of the motor 70 is calculated or estimated. In more detail, in the second embodiment, the rotation speed of the motor 70 is calculated or estimated from, for example, the applied voltage value and the output duty ratio. After that, the process proceeds to S125.

[0247] The applied voltage value corresponds to the magnitude of the voltage applied to the windings of the motor 70. The applied voltage value is estimated by the calculation of applied voltage value=output voltage value of the battery pack 40×output duty ratio÷100. The output duty ratio is the duty ratio of the PWM signal that the control circuit 60 outputs to the gate circuit 55.

[0248] In S825, the rotation speed of the tip connection part 30 is calculated or estimated based on the rotation speed of the motor 70 estimated or calculated in S815. Specifically, the rotation speed of the tip connection part 30 is calculated or estimated from the rotation speed of the motor 70 and the gear ratio of the reduction mechanism 75. Then, the process proceeds to S835.

[0249] In S835, the first displacement angle Δθ1 is calculated based on the rotation speed of the tip connector 30. The first displacement angle Δθ1 corresponds to the rotation angle of the tip connector 30 per control cycle. For example, when the rotation speed of the tip connector 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 process proceeds to S845.

[0250] In S845, the first displacement angle Δθ1 is added to the currently calculated reverse rotation angle θ, and the process ends. That is, in S845, the reverse rotation angle θ is updated. In S855, the reverse rotation angle θ is set to 0 degrees, and the process ends.

[0251] (2-6) Automatic stop judgment process in removal mode The automatic stop determination process in the removal mode of S615 (see FIG. 35) will be described with reference to the flowchart of FIG 38. The automatic stop determination process in the removal mode is a process for automatically stopping the motor 70 (more specifically, setting the automatic stop determination to ON) when it is estimated that the tip attachment 20 has been removed during the removal mode.

[0252] 38, in S905, a first automatic stop determination process is executed. The first automatic stop determination process is performed based on the reverse rotation angle θ of the tip connection portion 30. The first automatic stop determination process will be described later in detail.

[0253] In S915, a second automatic stop determination process is executed. The second automatic stop determination process is executed based on the rotation speed (actual rotation speed) of the motor 70. The second automatic stop determination process will be described in detail later.

[0254] In S925, a third automatic stop determination process is executed. The third automatic stop determination process is executed based on the elapsed time from the start of driving of the motor 70. The third automatic stop determination process will be described in detail later.

[0255] The first to third automatic stop determination processes will be described in detail below with reference to FIGS. (2-6-1) First automatic stop judgment process First, the details of the first automatic stop determination process of S905 will be described with reference to Fig. 39. As shown in Fig. 39, in the first automatic stop determination process, it is determined in S1010 whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S1010: YES), the process proceeds to S1020, and if it is determined that the removal mode is set to OFF (S1010: NO), the process proceeds to S1090.

[0256] In S1020, it is determined whether the automatic stop determination in the removal mode is set to OFF. If it is determined that the automatic stop determination in the removal mode is set to OFF (S1020: YES), the process proceeds to S1030, and if it is determined that the automatic stop determination in the removal mode is set to ON (S1020: NO), the process proceeds to S1060.

[0257] In S1030, an angle threshold is set according to the moment of inertia (i.e., the estimated moment of inertia or the designed moment of inertia). The angle threshold is the rotation angle from the start of reverse rotation of the tip connection part 30 that is required to detach the tip attachment 20 by rapid acceleration in the reverse direction. The rotation angle required for detachment differs depending on the moment of inertia. The smaller the moment of inertia, the larger the rotation angle required for detachment. The rotation angle required for detachment also differs depending on the acceleration at the start of reverse rotation. The greater the acceleration at the start of reverse rotation, the smaller the rotation angle required for detachment. In other words, the smaller the moment of inertia, the greater the acceleration and angle threshold required at the start of deceleration.

[0258] Therefore, in S1030, the angle threshold is calculated based on at least the moment of inertia. Note that, if the configuration is such that the moment of inertia is not estimated, in S1030, a predetermined value (for example, a value predetermined based on the design moment of inertia) is set as the angle threshold.

[0259] In S1040, it is determined whether the currently calculated reverse rotation angle θ is greater than the angle threshold value set in S1030. If it is determined that the reverse rotation angle θ is greater than the angle threshold value (S1040: YES), the process proceeds to S1050, and if it is determined that the reverse rotation angle θ is equal to or smaller than the angle threshold value (S1040: NO), this process ends.

[0260] In S1050, the automatic stop determination in the removal mode is set to ON, and then this process ends. In S1060, similarly to S830 in the first embodiment (see FIG. 26), it is determined whether the motor 70 has completely stopped. If the motor 70 has completely stopped (S1060: YES), the process proceeds to S1070, and if the motor 70 has not completely stopped (S1060: NO), the process ends.

[0261] In S1070, it is determined whether the trigger 14 is turned off. This determination may be made based on a trigger signal, for example. If the trigger 14 is turned off (S1070: YES), the process proceeds to S1080. If the trigger 14 is turned on (S1070: NO), the process ends.

[0262] In S1080, the automatic stop determination in the removal mode is set to OFF, and then this process is terminated. In S1090, the automatic stop determination in the removal mode is set to OFF, and then this process is terminated.

[0263] (2-6-2) Second automatic stop judgment process Next, details of the second automatic stop determination process of S915 will be described with reference to Fig. 40. Fig. 40 differs from Fig. 39 in S1110 and S1120. That is, in Fig. 40, S1030 and S1040 in Fig. 39 are changed to S1110 and S1120. The processes other than S1110 and S1120 are the same as those in Fig. 39.

[0264] In S1110, a second rotational speed threshold is set according to the moment of inertia (that is, the estimated moment of inertia or the design moment of inertia). The second rotational speed threshold corresponds to or near the rotational speed of the motor 70 in the reverse direction required to detach the tip attachment 20 by rapid acceleration in the reverse direction. That is, in the second embodiment, when the rotational speed of the motor 70 reaches the second rotational speed threshold in the removal mode, the tip attachment 20 is deemed to have been detached. In other words, the second rotational speed threshold is set to a rotational speed at which the tip attachment 20 can be deemed to have been detached.

[0265] Like the angle threshold described above, the second rotational speed threshold depends on the moment of inertia. The smaller the moment of inertia, the higher the rotational speed required for removal. The rotational speed required for removal also depends on the acceleration at the start of reverse rotation. The higher the acceleration at the start of reverse rotation, the lower the rotational speed required for removal. In other words, the smaller the moment of inertia, the higher the acceleration required at the start of deceleration and the second rotational speed threshold.

[0266] The second rotation speed threshold may be set based on, for example, the acceleration of the motor 70 from the start of reverse rotation and the above-mentioned angle threshold. For example, it is assumed that a value obtained by integrating the control rotation speed with respect to time from the start of reverse rotation reaches the angle threshold when time T0 has elapsed. In this case, the control rotation speed at the time TO has elapsed may be set as the second rotation speed threshold. Note that, in a configuration in which the moment of inertia is not estimated, a predetermined value is set as the second rotation speed threshold in S1110.

[0267] In S1120, it is determined whether the current actual rotation speed of the motor 70 is greater than the second rotation speed threshold set in S1110. If it is determined that the actual rotation speed is greater than the second rotation speed threshold (S1120: YES), the process proceeds to S1050, and if it is determined that the actual rotation speed is equal to or less than the second rotation speed threshold (S1120: NO), this process ends.

[0268] (2-6-3) Third automatic stop judgment process Next, details of the third automatic stop determination process of S925 will be described with reference to Fig. 41. Fig. 41 differs from Fig. 39 in S1160 and S1170. That is, in Fig. 41, S1030 and S1040 in Fig. 39 are changed to S1160 and S1170. The processes other than S1160 and S1170 are the same as those in Fig. 39.

[0269] In S1160, the elapsed time threshold is set according to the moment of inertia (i.e., the estimated moment of inertia or the designed moment of inertia). The elapsed time threshold corresponds to or near the rotation time of the motor 70 in the reverse direction required to detach the tip attachment 20 by rapid acceleration in the reverse direction. That is, in the second embodiment, when the reverse rotation time of the motor 70 reaches the elapsed time threshold in the removal mode, the tip attachment 20 is deemed to have been detached. In other words, the elapsed time threshold is set to a reverse rotation time that can be considered to have the tip attachment 20 detached.

[0270] As with the angle threshold described above, the elapsed time threshold varies with the moment of inertia. The smaller the moment of inertia, the longer the reverse rotation time required for removal. The reverse rotation time required for removal also varies with the acceleration at the start of reverse rotation. The greater the acceleration at the start of reverse rotation, the shorter the reverse rotation time required for removal. In other words, the smaller the moment of inertia, the greater the acceleration and elapsed time threshold required at the start of deceleration.

[0271] The elapsed time threshold may be set based on, for example, the acceleration of the motor 70 from the start of reverse rotation and the above-mentioned angle threshold. Specifically, for example, the above-mentioned time TO may be set as the elapsed time threshold. Note that, in a configuration in which the moment of inertia is not estimated, a predetermined value is set as the elapsed time threshold in S1160.

[0272] In S1170, it is determined whether the drive time from the start of reverse rotation of the motor 70 is greater than the elapsed time threshold set in S1160. If it is determined that the drive time from the start of reverse rotation is greater than the elapsed time threshold (S1170: YES), the process proceeds to S1050, and if it is determined that the drive time from the start of reverse rotation is equal to or less than the elapsed time threshold (S1170: NO), this process ends.

[0273] (2-7) Rotation direction setting process The rotation direction setting process of S411 (see FIG. 34) will be described with reference to the flowchart of FIG 42. The rotation direction setting process is a process for setting the rotation direction of the motor 70 to forward or reverse.

[0274] 42, in S1210, it is determined whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S1210: YES), the process proceeds to S1220, and if it is determined that the removal mode is set to OFF (S1210: NO), the process proceeds to S1230.

[0275] In S1220, the rotation direction of the motor 70 is set to reverse, and then the process ends. In S1230, the rotation direction of the motor 70 is set to the forward direction, after which the process ends. (2-8) State transition processing The state transition process of the second embodiment will be described with reference to the flowchart of FIG.

[0276] In the state transition processing in FIG. 43, steps S870, S880, S890, S900, S910, S950, S960, and S970 are the same as the state transition processing in the first embodiment shown in FIG. 27, and therefore descriptions thereof will be omitted here.

[0277] However, in the second embodiment, if it is determined in S890 that the trigger 14 is OFF, and if it is determined in S900 that the motor stop request is set ON, the process proceeds to S950.

[0278] In the second embodiment, after the control mode is set to the drive mode in S910, the process proceeds to S1300. In S1300, an output calculation process is executed. The details of the output calculation process are as shown in FIG.

[0279] (2-9) Output calculation process 44, when the process shifts to the output calculation process, it is determined in S1310 whether the removal mode is set to ON. If it is determined that the removal mode is set to ON (S1310: YES), the process proceeds to S1320, and if it is determined that the removal mode is set to OFF (S1310: NO), the process proceeds to S1360.

[0280] In S1320, a target rotation speed (specifically, a specified maximum speed) when the removal mode is set to ON is set. In S1330, an acceleration A1 of the motor 70 in the removal mode is set. The acceleration A1 is greater than an acceleration A2, which will be described later. The acceleration A1 has a magnitude that generates a release moment due to the acceleration caused by the acceleration A1. In other words, the acceleration A1 has a magnitude that allows the tip attachment 20 to be removed due to the acceleration caused by the acceleration A1. The acceleration A1 may be theoretically calculated based on the moment of inertia, for example, or may be experimentally determined.

[0281] In S1340, an applied voltage corresponding to the acceleration A1 set in S1330 is calculated. That is, an applied voltage to be applied to the motor 70 in order to start the motor 70 at the acceleration A1 is calculated.

[0282] In S1350, the output duty ratio of the PWM signal is calculated for applying the voltage calculated in S1340 to the motor 70. After that, this process ends. In S1360, a target rotation speed (specifically, a specified maximum speed) according to the set speed mode is set.

[0283] In S1370, the acceleration A2 of the motor 70 when the removal mode is off (i.e., when in the basic mode) is set. The acceleration A2 is smaller than the acceleration A1 described above. The acceleration A2 has a magnitude such that a release moment is not generated by the acceleration due to the acceleration A2. The acceleration A2 may be calculated theoretically or may be obtained experimentally.

[0284] In S1380, an application voltage corresponding to the acceleration A2 set in S1370 is calculated. That is, an application voltage to be applied to the motor 70 in order to start the motor 70 at the acceleration A2 is calculated.

[0285] In S1390, the output duty ratio of the PWM signal is calculated for applying the voltage calculated in S1380 to the motor 70. After that, this process ends. (2-10) Calculation of rotation angle The rotation angle calculation process in S90 (see FIG. 33) will be described in detail with reference to the flowchart in FIG.

[0286] In S1410, it is determined whether or not a request to obtain the reverse rotation angle θ of the tip connector 30 is ON. If the request to obtain the reverse rotation angle θ is ON (S1410: YES), the process proceeds to S1420, and if the request to obtain the reverse rotation angle θ is OFF (S1410: NO), this process ends.

[0287] In S1420, it is determined whether the position signal output from the position sensor 65 is as expected. Specifically, it is determined whether the position signals are being output from the three Hall sensors in the expected order based on the rotation direction of the motor 70. If it is determined that the position signal is as expected (S1420: YES), the process proceeds to S1430, and if it is determined that the position signal is not as expected (S1420: NO), the process proceeds to S1440.

[0288] In S1430, the second displacement angle Δθ2 is added to the currently calculated reverse rotation angle θ. The second displacement angle Δθ2 corresponds to the angle by which the tip connector 30 has rotated between two successive outputs of the position signal. For example, when the motor 70 is a four-pole motor, a mechanical angle of 360 degrees corresponds to an electrical angle of 360 degrees×2. Furthermore, when the gear ratio of the reduction mechanism 75 is 20, one rotation of the tip connector 30 corresponds to 20 rotations of the rotor. In this case, since the second displacement angle Δθ2 corresponds to an electrical angle of 60 degrees (i.e., between the outputs of the position signal), the motor is displaced by 30 degrees in mechanical angle while the tip connector 30 is displaced by the second displacement angle θ2. When the motor is displaced by 30 degrees, the tip connector 30 is displaced by 30 degrees÷20 (gear ratio). Therefore, the second displacement angle Δθ2 becomes 1.5 degrees. After the processing of S1430, this processing is terminated.

[0289] In S1440, the second displacement angle Δθ2 is subtracted from the currently calculated reverse rotation angle θ. If the position signal is not as expected, it is assumed that the rotor is rotating in the opposite direction. Therefore, the second displacement angle Δθ2 is subtracted from the current reverse rotation angle θ. Then, this process ends.

[0290] (2-11) Inverter control processing The inverter control process (S80 in FIG. 33) of the second embodiment will be described with reference to the flowchart in FIG.

[0291] In S405, the set control mode is acquired, similarly to S405 in Fig. 31. After that, the process proceeds to S1510. In S1510, the set rotation direction is obtained, and the process proceeds to S415.

[0292] In S415, similarly to S415 in FIG. 31, the calculated output duty ratio is acquired, and the process proceeds to S425. 31, in S425, the rotor position is obtained based on the position signal output from the position sensor 65. After that, the process proceeds to S1520.

[0293] In S1520, the INV control process is executed, and the process ends. Details of the INV control process in the second embodiment are as shown in FIG. (2-12) INV control processing As shown in FIG. 47, in the INV control process of the second embodiment, the currently set control mode is determined in S1610.

[0294] If the current control mode is the stop mode, the process proceeds to S1620. In S1620, the free-run stop process is executed similarly to S545 in Fig. 32. After the process of S1620, the process ends.

[0295] If the current control mode is the drive mode in S1610, the process proceeds to S1630. In S1630, the motor drive process is executed. Specifically, a motor control signal including a PWM signal is generated based on the control mode, rotation direction, output duty ratio, and position signal acquired in S405, S1510, S415, and S425, and the motor control PWM signal is output to the gate circuit 55. This drives the motor 70. After the process of S1630, the process ends.

[0296] (2-13) Correspondence of terms In the second embodiment, the acceleration A1 set in S1330 corresponds to an example of the first acceleration in the summary of the embodiment, and the acceleration A2 set in S1370 corresponds to an example of the second acceleration in the summary of the embodiment.

[0297] 3. Other embodiments Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be implemented in various modified forms.

[0298] (3-1) The moment of inertia may be estimated by any method. For example, the motor current value when the estimation motor applied voltage is applied to the motor 70 may be acquired and the moment of inertia may be estimated based on the motor current value. The motor current value corresponds to the magnitude of the current flowing through the motor 70. The motor current value is estimated, for example, by motor current value = battery current value ÷ output duty ratio × 100. It is predicted that the larger the moment of inertia is, the larger the motor current value will be. Therefore, the moment of inertia may be estimated so that the larger the motor current value is, the larger the value becomes.

[0299] (3-2) In the INV control process of the first embodiment, the first brake mode is not limited to three-phase short circuit brake. For example, it may be a combination of three-phase short circuit and two-phase short circuit, or it may be two-phase short circuit, or it may be a brake drive method other than three-phase short circuit and two-phase short circuit. Any brake drive method that can apply stronger brake than the second brake mode may be adopted.

[0300] The second brake mode is not limited to two-phase short circuit braking. For example, it may be a combination of three-phase short circuit and two-phase short circuit, or a brake driving method other than three-phase short circuit and two-phase short circuit. Any brake driving method that can apply a weaker brake than the first brake mode may be adopted.

[0301] (3-3) In each of the above embodiments, the cleaning device 1 is a handheld type, but the cleaning device 1 is not limited to a handheld type. The cleaning device 1 may be, for example, a push type equipped with wheels.

[0302] (3-4) In each of the above embodiments, the cleaning device 1 includes the battery mounting unit 41, but it may include a power cord instead of or in addition to the battery mounting unit 41. That is, the cleaning device 1 may receive power from an external power source such as a commercial power source by connecting the power cord to the external power source.

[0303] (3-5) In each of the above embodiments, the tip connection portion 30 has three first claws, but may have one, two, or four or more first claws. The tip attachment 20 has three second claws, but may have one, two, or four or more second claws.

[0304] (3-6) Multiple functions possessed by one component in the above embodiments may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Also, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments. [Explanation of symbols]

[0305] 1...cleaning device, 12...first gripping portion, 13...second gripping portion, 14...trigger, 20...tip attachment, 23-25...second claw, 30...tip connection portion, 33-35...first claw, 50...controller, 55...gate circuit, 56...inverter circuit, 60...control circuit, 60a...CPU, 60b...memory, 65...position sensor, 70...motor, 70a, 70b, 70c...terminals, 154...removal mode switch.

Claims

1. Motor and, A drive circuit configured to supply power to the motor and drive the motor, A cleaning tool is configured to be detachably attached, and is configured to be rotated in a first or second rotational direction by the motor, and has an engaging portion configured to engage with an engaging portion of the cleaning tool, and is configured so that when the detached cleaning tool is rotated from a predetermined position in the first rotational direction, the engaging portion engages with the engaging portion and the cleaning tool is attached, and has a tip connecting portion having a moment of inertia smaller than the moment of inertia of the cleaning tool, A switch is configured to be manually operated to selectively switch the operating mode of the motor between a first mode for performing cleaning with the cleaning tool and a second mode for detaching the cleaning tool from the tip connection part. A control unit, In the first mode, the motor is rotated in the first rotational direction via the drive circuit. In the second mode, release control is performed to control the drive circuit so that a release force is generated in the cleaning tool by the rotation of the motor, and the release force is a relative force in the first rotational direction with respect to the tip connection portion and has a magnitude that is sufficient to release the engagement between the engaging portion and the engaged portion. A control unit configured as follows, A cleaning device equipped with the following features.

2. A cleaning device according to claim 1, The control unit is configured to rotate the motor in the first rotational direction in the second mode. The release control includes, in response to the fulfillment of predetermined brake initiation requirements for initiating the braking of the motor, applying a first brake to the motor via the drive circuit to decelerate the motor and thereby generating the release force in the cleaning tool. Cleaning equipment.

3. A cleaning device according to claim 2, The motor is equipped with a speed detection unit configured to detect the actual rotational speed of the motor, The brake initiation requirement is met based on the fact that the actual rotational speed detected by the speed detection unit is equal to or greater than the first rotational speed threshold. Cleaning equipment.

4. The cleaning device according to claim 2, The control unit is configured to control the drive circuit in the second mode so that the motor accelerates from a stopped state toward a target rotational speed. The brake initiation requirement is met based on the elapsed time since the start of the motor's operation. Cleaning equipment.

5. A cleaning device according to any one of claims 2 to 4, In the second mode, the control unit is configured to control the drive circuit so that, in response to the fulfillment of the brake start requirement, it opens the power supply path from the drive circuit to the motor for a first time before applying the first brake to the motor, thereby allowing the motor to run free. Cleaning equipment.

6. A cleaning device according to any one of claims 2 to 4, The control unit is configured to control the drive circuit in the first mode, in response to the first stop requirement for stopping the motor being met, to allow the motor to run free by opening the power supply path from the drive circuit to the motor without applying the brakes to the motor. Cleaning equipment.

7. A cleaning device according to any one of claims 2 to 4, The control unit is configured, in the first mode, to apply a second brake to the motor via the drive circuit, which has a weaker braking force than the first brake, when the first stop requirement for stopping the motor is met. Cleaning equipment.

8. A cleaning device according to claim 7, The control unit is configured to control the drive circuit in the first mode so as to allow the motor to run free for a second time before applying the second brake to the motor, by opening the power supply path from the drive circuit to the motor, in response to the first stop requirement being met. Cleaning equipment.

9. A cleaning device according to claim 5, In the first mode, the control unit responds when the first stop requirement for stopping the motor is met. For a second time shorter than the first time, the drive circuit is controlled to open the path supplying power from the drive circuit to the motor, thereby allowing the motor to run free. After the elapsed time of the second period, a second brake with less braking force than the first brake is applied to the motor via the drive circuit. It is structured in such a way. Cleaning equipment.

10. A cleaning device according to claim 7, The motor is a brushless motor equipped with three terminals for receiving the power, The second brake includes a two-phase short-circuit brake that electrically short-circuits any two of the three terminals. Cleaning equipment.

11. A cleaning device according to claim 2, The motor is a brushless motor equipped with three terminals for receiving the power, The first brake includes a three-phase short-circuit brake that electrically short-circuits the three terminals to each other. Cleaning equipment.

12. A cleaning device according to claim 1, The release control is a cleaning device that generates the release force in the cleaning tool by controlling the drive circuit to accelerate the motor from a stopped state in the second rotation direction with a first acceleration.

13. A cleaning device according to claim 12, In the first mode, the control unit is configured to accelerate the motor with a second acceleration lower than the first acceleration when driving the motor. Cleaning equipment.

14. A cleaning device according to claim 12, The aforementioned release control includes stopping the motor after the motor has started to drive, in accordance with the fulfillment of a second stop requirement. Cleaning equipment.

15. A cleaning device according to claim 14, The second stopping requirement is met based on the actual rotational speed of the motor exceeding the second rotational speed threshold. Cleaning equipment.

16. A cleaning device according to claim 14, The second stopping requirement is met based on the rotation angle of the tip connection portion in the second rotational direction from the start of the motor's operation exceeding an angle threshold. Cleaning equipment.

17. A cleaning device according to claim 14, The second stop requirement is met based on the fact that the elapsed time from the start of the motor's operation exceeds the elapsed time threshold. Cleaning equipment.

18. A cleaning device according to claim 1, The control unit is configured to switch the operating mode to the first mode based on the fact that the motor has been driven in the second mode for a predetermined number of consecutive times or more. Cleaning equipment.

19. A cleaning device according to claim 1, The cleaning device is equipped with a gripping portion configured to be held by the user of the cleaning device, The cleaning device is a handheld type that is used while being supported by the user via the gripping part. Cleaning equipment.

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