electric vacuum cleaner

Abstract

This invention provides an electric vacuum cleaner that can continue driving the motor and ensure operating time even when the output voltage of the secondary battery is prone to decrease. The electric vacuum cleaner of this embodiment includes a motor, a secondary battery, and a control unit. The secondary battery supplies power to the motor. The control unit determines the magnitude of a control element for the power supplied from the secondary battery to the motor based on information indicating the state of the secondary battery.

Description

Technical Field

[0001] Embodiments of the present invention relate to electric vacuum cleaners.

[0002] This application is based on Japanese Patent Application 2019-083231 (filed April 24, 2019) and Japanese Patent Application 2020-006902 (filed January 20, 2020), from which it enjoys priority benefits. This application incorporates the entire contents of those applications by reference. Background Technology

[0003] Electric vacuum cleaners are known to have an electric motor and a secondary battery that supplies power to the motor. If the secondary battery becomes over-discharged, its lifespan will be shortened. Therefore, when the terminal voltage of the secondary battery drops to a preset discharge termination voltage, the electric vacuum cleaner needs to be stopped to accelerate the charging of the secondary battery.

[0004] However, the output voltage tends to decrease when the secondary battery deteriorates significantly or its internal resistance increases. Therefore, if you want to use an electric vacuum cleaner when the secondary battery is deteriorating significantly or its internal resistance is increasing, there is a possibility that even if the secondary battery still has remaining capacity, the terminal voltage of the secondary battery will be lower than the discharge termination voltage, causing the electric vacuum cleaner to stop.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2018-19998 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] The problem to be solved by the present invention is to provide an electric vacuum cleaner that can continue to drive the motor and ensure the running time even when the output voltage of the secondary battery is prone to decrease.

[0010] Methods used to solve problems

[0011] The electric vacuum cleaner of this embodiment includes an electric motor, a secondary battery, and a control unit. The secondary battery supplies power to the electric motor. The control unit determines the magnitude of a control element for the power supplied from the secondary battery to the electric motor based on information indicating the state of the secondary battery.

[0012] Invention Effects

[0013] According to the present invention, even when the output voltage of the secondary battery is prone to decrease, the motor can continue to be driven and the running time can be ensured. Attached Figure Description

[0014] Figure 1 This is a perspective view of an electric vacuum cleaner according to the first embodiment.

[0015] Figure 2 This is a block diagram showing the circuit configuration of the electric vacuum cleaner according to the first embodiment.

[0016] Figure 3 This is a schematic diagram illustrating the electric blower of the first embodiment.

[0017] Figure 4 Is with Figure 3 The timing diagram corresponding to the electric blower model shown.

[0018] Figure 5 This is a diagram illustrating an example of the range of variation in the current value supplied to the electric blower in the first embodiment.

[0019] Figure 6 This is a diagram illustrating an example of the contents of the first reference table of the first embodiment.

[0020] Figure 7 This diagram illustrates an example of the control mode of the electric blower according to the first embodiment.

[0021] Figure 8 This is a diagram used to illustrate the changes in characteristics caused by the deterioration of the secondary battery in the first embodiment.

[0022] Figure 9 This is a diagram showing the second reference table of the first embodiment.

[0023] Figure 10 This is a flowchart illustrating the charging process of the secondary battery according to the first embodiment.

[0024] Figure 11 This is a diagram showing the third reference table of the first embodiment.

[0025] Figure 12 This is a flowchart illustrating the processing flow when using the electric vacuum cleaner according to the first embodiment.

[0026] Figure 13 This is a diagram illustrating an example of the contents of a reference table showing a first variation of the first embodiment.

[0027] Figure 14 This is a diagram showing a reference table of a third variation of the first embodiment.

[0028] Figure 15 This is a diagram illustrating the method for detecting the internal resistance of a secondary battery according to the second embodiment.

[0029] Figure 16 This is a diagram illustrating an example of the contents of a reference table for the second embodiment.

[0030] Figure 17 This is a flowchart illustrating the processing flow when using the electric vacuum cleaner according to the second embodiment.

[0031] Figure 18 This is a diagram of a reference table showing a first variation of the second embodiment.

[0032] Figure 19 This is a diagram of a reference table showing a second variation of the second embodiment.

[0033] Figure 20 This is a diagram showing a reference table for the third embodiment.

[0034] Figure 21 This is a schematic diagram illustrating the electric blower of the fourth embodiment.

[0035] Figure 22 Is with Figure 21 The timing diagram corresponding to the electric blower model shown.

[0036] Explanation of reference numerals in the attached figures

[0037] 1… Electric vacuum cleaner, 14, 14A… Electric blower (motor), 43… Secondary battery, 65… Voltage detection unit, 46… Temperature detection unit, 71… Main unit storage unit (storage unit), 74… Main unit control unit (control unit). Detailed Implementation

[0038] Hereinafter, the electric vacuum cleaner according to the embodiments will be described with reference to the accompanying drawings. In the following description, components having the same or similar functions will be labeled with the same reference numerals. Moreover, repeated descriptions of these components will sometimes be omitted. In this specification, "based on XX" means "at least based on XX", and also includes cases where it is based on other elements besides XX. Furthermore, "based on XX" is not limited to the direct use of XX, and also includes cases based on elements obtained by calculation or processing of XX. "XX" is any element (e.g., any information). In addition, "during this use" as used in this specification means using the electric vacuum cleaner after "the last use".

[0039] (First Implementation)

[0040] <1. Overall Components of an Electric Vacuum Cleaner>

[0041] First, refer to Figures 1 to 12The electric vacuum cleaner 1 according to the first embodiment will be described. The first embodiment is an example of determining the magnitude of the control element of the electric blower 14 based on information indicating the deterioration state of the secondary battery 43 mounted on the electric vacuum cleaner 1. Hereinafter, the power-on time will be described as an example of the control element.

[0042] Figure 1 This is a perspective view showing the electric vacuum cleaner 1 according to the first embodiment. The electric vacuum cleaner 1 of this embodiment is, for example, a so-called stick vacuum cleaner, which has a built-in secondary battery 43 (see reference). Figure 2 The cordless electric vacuum cleaner 1 is not limited to the example above, but may also be a canister or other type of electric vacuum cleaner with a vacuum cleaner body including wheels.

[0043] The electric vacuum cleaner 1, for example, includes a main unit MU and a secondary battery unit BU. The main unit MU includes, for example, the vacuum cleaner body 10, an extension tube 20, and a suction inlet (floor brush) 30.

[0044] First, the vacuum cleaner body 10 will be described. The vacuum cleaner body 10 includes, for example, a main body shell 11, a handle 12, a dust collection device 13, and an electric blower 14.

[0045] The main housing 11 forms the outer contour of the vacuum cleaner body 10. The main housing 11 houses the electric blower 14 and the secondary battery unit BU. In addition, the main housing 11 has an extension tube connection portion 11a for connecting one end of the extension tube 20, which will be described later.

[0046] The handle 12 is located at the upper rear end of the main housing 11. The handle 12 is the part held by the user when vacuuming the floor surface (the surface to be vacuumed). The handle 12 is provided with an operation section 16, which accepts user operations to select the operation of the electric blower 14 and the rotating brush 33 (described later). The operation section 16 includes, for example, a plurality of operation buttons 16a.

[0047] The operation buttons 16a include a power button for turning the power on / off of the electric vacuum cleaner 1, and one or more mode selection buttons for switching the operating modes (running modes) of the electric vacuum cleaner 1. The operating modes of the electric vacuum cleaner 1 include, for example, a "weak mode" that causes the electric blower 14 (described later) to rotate at a low speed and a "strong mode" that causes the electric blower 14 to rotate at a high speed. Additionally, the operating modes of the electric vacuum cleaner 1 include a "brush rotation mode" that causes the rotating brush 33 (described later) to rotate and a "brush stop mode" that prevents the rotating brush 33 from rotating.

[0048] The dust collection device 13 is installed on the main housing 11. The dust collection device 13 is a device that separates dust contained in the air drawn into the vacuum cleaner body 10 by the action of the electric blower 14 (described later). The dust collection device 13 is, for example, a multi-stage centrifugal separation type dust collection device that centrifugally separates dust contained in the air drawn into the vacuum cleaner body 10. However, the dust collection device 13 can also be a single-stage centrifugal separation type dust collection device or a dust collection device including a paper bag filter, etc.

[0049] The electric blower 14 includes a motor, referred to as a fan motor or main motor, which generates negative pressure by driving it. The electric blower 14 draws dust-laden air into the dust collection device 13 through the suction port 35 of the suction body 30 (described later) using the generated negative pressure. After the air has been self-cooled by the dust collection device 13, the air is exhausted. The motor of the electric blower 14 is, for example, a DC motor, but is not limited to this. The electric blower 14 is an example of an "electric motor".

[0050] Next, the extension tube 20 will be described. The extension tube 20 is, for example, formed as a long strip, having a first end 21 and a second end 22. The first end 21 of the extension tube 20 is airtightly connected to the extension tube connection portion 11a of the vacuum cleaner body 10. The second end 22 of the extension tube 20 is airtightly connected to the suction inlet body 30. Inside the extension tube 20, there are connecting wires that electrically connect the vacuum cleaner body 10 and the suction inlet body 30.

[0051] Next, the suction inlet body 30 will be described. The suction inlet body 30 is a part that moves along the floor surface. The suction inlet body 30 includes, for example, a suction inlet body housing 31, a connecting pipe 32, a rotating brush 33, and a brush motor 34.

[0052] The suction inlet housing 31 is elongated in the horizontal direction (left-right direction). The suction inlet housing 31 houses a brush motor 34. Additionally, the suction inlet housing 31 has a suction port 35 at its lower portion facing the floor. The suction port 35 is an opening for drawing dust from the floor surface by driving an electric blower 14.

[0053] The connecting pipe 32 is a portion used for airtight connection between the suction inlet housing 31 and the second end 22 of the extension pipe 20, and is rotatably connected to the suction inlet housing 31. By connecting the suction inlet housing 31 and the extension pipe 20 through the connecting pipe 32, an air path is formed from the suction inlet 35 of the suction inlet housing 31 through the extension pipe 20 to the vacuum cleaner body 10.

[0054] A rotating brush 33 is provided at the suction port 35 and is arranged along the floor surface. The rotating brush 33 is arranged in a manner that allows it to rotate relative to the suction port housing 31. The rotating brush 33 serves to lift dust from the floor surface or to make the fibers of carpets, etc., stand up.

[0055] Brush motor 34 is mechanically connected to rotating brush 33 via a rotary drive mechanism (not shown), driving rotating brush 33 (causing rotating brush 33 to rotate). Brush motor 34 is, for example, a DC motor, but is not limited to this. Brush motor 34 is another example of an "electric motor".

[0056] The secondary battery unit BU supplies the main unit MU with the power required for the main unit MU to operate. Details about the secondary battery unit BU will be described later.

[0057] Next, the charging device 8 attached to the electric vacuum cleaner 1 will be described. The charging device 8 has a receiving part for mounting the electric vacuum cleaner 1, supporting the electric vacuum cleaner 1 when not in use. The charging device 8 connects to an external power source PG (see reference). Figure 2 Electrical connection. By mounting the electric vacuum cleaner 1 to the charging device 8, the secondary battery unit BU of the electric vacuum cleaner 1 is charged by being electrically connected to an external power source PG via the charging device 8. Alternatively, the charging device 8 may be, for example, an AC adapter or the like, connected to the electric vacuum cleaner 1 while it is leaning against a wall in a room. The charging device 8 includes a power conversion circuit 8a (see reference 8a) that converts the power supplied from the external power source PG into power suitable for charging the secondary battery 43. Figure 2 ).

[0058] <2. Circuit Structure of an Electric Vacuum Cleaner>

[0059] Next, the circuit configuration of the electric vacuum cleaner 1 will be explained.

[0060] Figure 2 This is a block diagram showing the circuit configuration of the electric vacuum cleaner 1. Figure 2 In the diagram, solid lines represent power lines that supply electricity, while dashed lines represent the flow of signals (information).

[0061] <2.1 Circuit configuration of the secondary battery unit BU>

[0062] First, the circuit configuration of the secondary battery unit BU will be explained. The secondary battery unit BU includes, for example, connection terminals 41A and 41B, power lines 42A and 42B, a secondary battery 43, a current detection unit 44, a voltage detection unit 45, a temperature detection unit 46, a secondary battery unit storage unit 51, a secondary battery unit communication unit 52, and a secondary battery unit control unit 53.

[0063] Connection terminals 41A and 41B are exposed on the outside of the outer casing of the secondary battery unit BU. When the secondary battery unit BU is installed in the main unit MU, power lines 42A and 42B are electrically connected to the power lines 62A and 62B of the main unit MU via connection terminals 41A and 41B and connection terminals 61A and 61B of the main unit MU. In this embodiment, the power lines 42A and 42B of the secondary battery unit BU and the power lines 62A and 62B of the main unit MU form a power line that electrically connects the secondary battery 43 to the drive source (electric blower 14, brush motor 34). Power line 42A is, for example, a positive wire. Power line 42B is, for example, a negative wire that is paired with power line 42A.

[0064] The secondary battery 43 is, for example, a battery pack consisting of multiple batteries connected in series or parallel. The secondary battery 43 supplies power to the main unit MU via power lines 42A and 42B. Thus, the various components of the main unit MU (e.g., the electric blower 14, brush motor 34, main unit storage unit 71 (described later), main unit communication unit 73 (described later), and main unit control unit 74 (described later)) are operated by the power supplied from the secondary battery 43. Furthermore, the secondary battery 43 supplies power to the various functional units of the secondary battery unit BU (e.g., the secondary battery unit storage unit 51, the secondary battery unit communication unit 52, and the secondary battery unit control unit 53). In this specification, "supplying power from the secondary battery" is not limited to the case where power output from the secondary battery 43 is directly supplied to the target component; it also includes the case where power is supplied from the secondary battery 43 to a power circuit provided between the secondary battery 43 and the target component, and where power, in which voltage has been adjusted, is supplied to the target component from the power circuit.

[0065] The current detection unit 44 is connected to the power line 42A, for example, inside the secondary battery cell BU, and detects the current value flowing from the secondary battery 43 during discharge and the current value flowing into the secondary battery 43 during charging. The voltage detection unit 45 is connected to the power lines 42A and 42B, for example, inside the secondary battery cell BU, and detects the voltage value of the terminal voltage of the secondary battery 43. The temperature detection unit 46 is located near the secondary battery 43, for example, inside the secondary battery cell BU, and detects the temperature of the secondary battery 43. The detection results of the current detection unit 44, the voltage detection unit 45, and the temperature detection unit 46 are output to the secondary battery cell control unit 53.

[0066] The secondary battery cell storage unit 51 is located inside the secondary battery cell BU. The secondary battery cell storage unit 51 is, for example, a non-volatile memory such as EEPROM (Electrically Erasable Programmable Read-only Memory). Secondary battery status information BSb, generated later by the secondary battery cell control unit 53, is written into the secondary battery cell storage unit 51.

[0067] The secondary battery unit communication unit 52 is located inside the secondary battery unit BU. The secondary battery unit communication unit 52 includes, for example, a high-frequency communication circuit. The secondary battery unit communication unit 52 communicates with the main unit communication unit 73 (described later in the text) of the main unit MU, sending the secondary battery status information BSb generated by the secondary battery unit control unit 53 to the main unit MU. Furthermore, communication between the secondary battery unit communication unit 52 and the main unit communication unit 73 can be conducted via wired or wireless means.

[0068] The secondary battery unit control unit 53 is located inside the secondary battery unit BU and controls the entire secondary battery unit BU. In this embodiment, the secondary battery unit storage unit 51, the secondary battery unit communication unit 52, and the secondary battery unit control unit 53 are implemented, for example, by a single IC (Integrated Circuit) component such as a microcomputer. However, the secondary battery unit storage unit 51, the secondary battery unit communication unit 52, and the secondary battery unit control unit 53 can also be implemented by different components. The secondary battery unit control unit 53, for example, includes a status detection unit 53a and a status information generation unit 53b.

[0069] The state detection unit 53a detects the state of the secondary battery 43 based on the detection results from the current detection unit 44, voltage detection unit 45, and temperature detection unit 46. The "state of the secondary battery" may include, for example, one or more of the following: (a) the deterioration state of the secondary battery 43, (b) the state of the internal resistance of the secondary battery 43, and (c) the temperature state of the secondary battery 43. Furthermore, the detection methods and timing for the deterioration state, the internal resistance state, and the temperature state of the secondary battery 43 are, for example, the same as those described and timed in the description of the main unit MU. The detection results from the state detection unit 53a are output to the state information generation unit 53b. In this specification, "temperature state" can refer to temperature itself or to a classification of temperatures (low temperature, medium temperature, high temperature, etc.).

[0070] The status information generation unit 53b generates secondary battery status information BSb representing the status of the secondary battery 43 based on the detection results of the status detection unit 53a. The secondary battery status information BSb may include one or more of the following: (a) the degradation state of the secondary battery 43, (b) the state of the internal resistance of the secondary battery 43, and (c) the temperature state of the secondary battery 43, as well as a timestamp indicating the time when the secondary battery status information BSb was generated. Additionally, the secondary battery status information BSb may also include detection results based on the current detection unit 44 and the voltage detection unit 45. The status information generation unit 53b writes the generated secondary battery status information BSb into the secondary battery cell storage unit 51 and outputs it to the secondary battery cell communication unit 52. The secondary battery cell communication unit 52 sends the secondary battery status information BSb received from the status information generation unit 53b to the main unit communication unit 73.

[0071] <2.2 Circuit Structure of the Main Unit MU>

[0072] Next, the circuit configuration of the main unit MU will be described. The main unit MU includes, for example, connection terminals 61A and 61B, power lines 62A and 62B, a first switch unit 63, a second switch unit 64, a voltage detection unit 65, a first current detection unit 66, a second current detection unit 67, a main unit storage unit 71, a control power supply unit 72, a main unit communication unit 73, a main unit control unit 74, and external connection terminals 76A and 76B.

[0073] Connection terminals 61A and 61B are connected to connection terminals 41A and 41B of the secondary battery unit BU. Power lines 62A and 62B are electrically connected to connection terminals 61A and 61B. Power line 62A is, for example, a positive wire. Power line 62B is, for example, a negative wire that is paired with power line 62A.

[0074] Power lines 62A and 62B include power lines 62Aa and 62Ba for the electric blower and power lines 62Ab and 62Bb for the brush motor. Power lines 62Aa and 62Ba for the electric blower electrically connect terminals 61A and 61B to the electric blower 14. For example, power line L1, which is part of power lines 62Aa and 62Ba for the electric blower, connects the first switching unit 63 to the electric blower 14. Power lines 62Ab and 62Bb for the brush motor electrically connect terminals 61A and 61B to the brush motor 34. For example, power line L2, which is part of power lines 62Ab and 62Bb for the brush motor, connects the second switching unit 64 to the brush motor 34.

[0075] A first switching unit 63 is disposed between the secondary battery 43 and the electric blower 14. The first switching unit 63 is composed of one or more semiconductor switching elements. When the first switching unit 63 is closed, power is supplied to the electric blower 14 from the secondary battery 43. On the other hand, when the first switching unit 63 is opened, the power supply to the electric blower 14 from the secondary battery 43 is stopped. By controlling the first switching unit 63 to be turned on and off at a predetermined period, pulsed input power is supplied from the secondary battery 43 to the electric blower 14.

[0076] A second switching unit 64 is disposed between the secondary battery 43 and the brush motor 34. The second switching unit 64 is composed of one or more semiconductor switching elements. When the second switching unit 64 is closed, power is supplied from the secondary battery 43 to the brush motor 34. On the other hand, when the second switching unit 64 is opened, the power supply from the secondary battery 43 to the brush motor 34 is stopped. By controlling the second switching unit 64 to be turned on and off at a predetermined cycle, pulsed input power is supplied from the secondary battery 43 to the brush motor 34.

[0077] The voltage detection unit 65 is connected, for example, to the power lines 62Aa and 62Ba of the electric blower, and detects the voltage value (e.g., equivalent to the terminal voltage of the secondary battery 43) of the power input to the electric blower 14 and the brush motor 34. The detection result of the voltage detection unit 65 is output to the main unit control unit 74.

[0078] The first current detection unit 66 is connected, for example, to the power line 62Aa of the electric blower, and detects the current value of the current supplied from the secondary battery 43 to the electric blower 14. The second current detection unit 67 is connected, for example, to the power line 62Ab of the brush motor, and detects the current value of the current supplied from the secondary battery 43 to the brush motor 34. The detection results of the first current detection unit 66 and the second current detection unit 67 are output to the main unit control unit 74.

[0079] The main unit storage unit 71 is, for example, a non-volatile memory such as an EEPROM. Secondary battery status information BSa (described later) generated by the main unit control unit 74 is written into the main unit storage unit 71, for example.

[0080] The control power supply unit 72 is electrically connected to power lines 62A and 62B, for example. For instance, a portion of the power supplied from the secondary battery 43 to power line 62A is input to the control power supply unit 72. The control power supply unit 72 is, for example, a constant voltage power supply circuit that generates the desired DC voltage. The control power supply unit 72 converts (steps down) the input power into power suitable for the main unit storage unit 71, the main unit communication unit 73, and the main unit control unit 74, and supplies the converted power to these components.

[0081] The main unit communication unit 73 includes, for example, a high-frequency circuit for communication. The main unit communication unit 73 communicates with the secondary battery unit communication unit 52 of the secondary battery unit BU, and receives secondary battery status information BSb sent from the secondary battery unit communication unit 52. The main unit communication unit 73 outputs the received secondary battery status information BSb to the main unit control unit 74.

[0082] The main unit control unit 74 controls the entire main unit MU. In this embodiment, the main unit storage unit 71, the main unit communication unit 73, and the main unit control unit 74 are implemented, for example, by a single IC component such as a microcomputer. However, the main unit storage unit 71, the main unit communication unit 73, and the main unit control unit 74 can also be implemented by different components. The main unit control unit 74 includes, for example, an electric blower control unit 74a, a brush motor control unit 74b, a status detection unit 74c, a status information generation unit 74d, and a power-on time determination unit 74e.

[0083] The electric blower control unit 74a controls the drive of the electric blower 14. For example, the electric blower control unit 74a controls the first switching unit 63 to turn on / off based on the lead angle and energizing time for controlling the electric blower 14, thereby controlling the drive of the electric blower 14.

[0084] The brush motor control unit 74b controls the drive of the brush motor 34. For example, the brush motor control unit 74b controls the second switching unit 64 to turn on / off based on the lead angle and energizing time for controlling the brush motor 34, thereby controlling the drive of the brush motor 34.

[0085] The state detection unit 74c detects the state of the secondary battery 43 based on the detection results from the voltage detection unit 65, the first current detection unit 66, the second current detection unit 67, and the temperature detection unit 46 of the secondary battery cell BU. In this embodiment, the state detection unit 74c detects the deterioration state of the secondary battery 43 as the state of the secondary battery 43. This will be described in detail later.

[0086] Based on the detection results of the state detection unit 74c, the state information generation unit 74d generates secondary battery state information BSa, representing the state of the secondary battery 43. The secondary battery state information BSa includes a timestamp indicating the time when it was generated. The state information generation unit 74d writes the generated secondary battery state information BSa as at least part of historical data representing the state of the secondary battery 43 into the main unit storage unit 71. Alternatively, the state information generation unit 74d may also write secondary battery state information BSb, sent from the secondary battery unit communication unit 52 and received by the main unit communication unit 73, as at least part of the aforementioned historical data into the main unit storage unit 71.

[0087] The power-on time determination unit 74e determines the power-on time (e.g., the power-on time of the electric blower 14 supplied from the secondary battery 43 to the electric blower 14 per predetermined unit rotation of the electric blower 14) based on information indicating the state of the secondary battery 43. This will be described in detail later. The power-on time determination unit 74e may also determine the power-on time (e.g., the power-on time of the brush motor 34 supplied from the secondary battery 43 to the brush motor 34 per predetermined unit rotation of the brush motor 34) based on information indicating the state of the secondary battery 43. In the following description, the control of the electric blower 14 will be illustrated; the control of the brush motor 34 will also be described in the same way.

[0088] External connection terminals 76A and 76B are connected to power lines 62A and 62B respectively inside the main body unit MU. External connection terminals 76A and 76B are exposed on the outside of the electric vacuum cleaner 1 and are connected to the charging device 8.

[0089] <3. Control>

[0090] (3.1 Control Elements)

[0091] First, the control elements ("lead angle" and "energizing time") of the electric blower 14 will be explained.

[0092] Figure 3 This is a schematic diagram illustrating the electric blower 14. Additionally, in Figure 3 For the sake of simplicity, a model of a bipolar electric blower 14 is shown. However, the electric blower 14 can also be a three- or higher electric blower.

[0093] An electric blower 14, for example, includes a first stator coil LA, a second stator coil LB, a rotor RT, and a position detector PD. The first stator coil LA and the second stator coil LB are configured, for example, in a pole-pole relationship. The position detector PD is configured, for example, at a position corresponding to the stator coil LB. The position detector PD detects the position (phase) of the rotor RT by detecting the polarity of the nearest pole of the rotor RT. Figure 3 In the state shown, the position detector PD detects the S pole.

[0094] Figure 4 Is with Figure 3 The timing diagram corresponding to the model of the electric blower 14 shown. Figure 4 In the attached diagram, the reference numeral T indicates the period of one revolution of the electric blower 14. One period is the time from time tM11 to time tM21. Similarly, one period is the time from time tM12 to time tM22. Figure 4 In the example shown, time passes in the order of tM11, tM12, tM21, and tM22. The rotor RT of the electric blower 14 rotates at a predetermined speed corresponding to the period T.

[0095] At time tM11, position detector PD detects the N pole instead of the S pole. Based on the detection result of position detector PD, main unit control unit 74 starts energizing stator coil LA at time tM11, and stops energizing stator coil LA after a predetermined time ETA. Similarly, at time tM12, position detector PD detects the S pole instead of the N pole. Based on the detection result of position detector PD, main unit control unit 74 starts energizing stator coil LB at time tM12, and stops energizing stator coil LB after a predetermined time ETB. If these predetermined times ETA and ETB are extended, the current value supplied to electric blower 14 increases.

[0096] Here, the specified time ETA and the specified time ETB are examples of the "energizing time" of the electric blower 14. In this embodiment, the energizing time determination unit 74e determines the energizing time of the power supplied from the secondary battery 43 to the electric blower 14 in each specified unit rotation of the electric blower 14. The "specified unit rotation" can be a rotation of 1 / 4 revolution, a rotation of half a revolution, a rotation of 1 revolution, a rotation of 2 revolutions or more, or any other rotation. For example, "the energizing time of the power supplied from the secondary battery to the motor in each rotation of the motor" refers to the total time of the specified time ETA and the specified time ETB. Here, the specified time ETA and the specified time ETB are generally set to the same length. Therefore, hereafter, the specified time ETA and the specified time ETB are not distinguished and are referred to as "energizing time ET", and the method of determining the energizing time ET based on the state of the secondary battery 43 will be described.

[0097] On the other hand, "lead angle" refers to the offset of the phase (timing) of the power supplied to the reference phase (the switching point between the S and N poles) of the rotor RT. Figure 4 The solid lines representing the energizing states of the first stator coil LA and the second stator coil LB indicate the case where the lead angle θ is zero. On the other hand, Figure 4 The double-dotted line representing the energization state of the second stator coil LB indicates the presence of a lead angle θ. If the lead angle θ is increased, the rotational speed of the electric blower 14 increases, and the current value supplied to the electric blower 14 (current value per unit time) increases.

[0098] Therefore, the main unit control unit 74 can change the current value of the current supplied from the secondary battery 43 to the electric blower 14 by adjusting at least one of the lead angle θ of the electric blower 14 and the energizing time ET.

[0099] (3.2 Range of Current Value Changes)

[0100] Figure 5 This is a diagram illustrating an example of the range of changes in the current value supplied from the secondary battery 43 to the electric blower 14. Additionally, Figure 5 This example represents a new secondary battery 43 (when the secondary battery 43 has not deteriorated). In this embodiment, when operating in "strong mode," the current supplied to the electric blower 14 varies, for example, between 15 [A] and 8 [A]. On the other hand, when operating in "weak mode," the current supplied to the electric blower 14 varies, for example, between 8 [A] and 6 [A]. Furthermore, the following explanation will be based on the case where the electric vacuum cleaner 1 is driven in "strong mode."

[0101] Here, we will provide a supplementary explanation of the reason for changing the current value supplied from the secondary battery 43 to the electric blower 14. If the secondary battery 43 continues to discharge, the terminal voltage of the secondary battery 43 gradually decreases. As a result, if the terminal voltage of the secondary battery 43 falls below a predetermined threshold (hereinafter referred to as the "discharge termination voltage value"), it is necessary to stop the operation of the electric vacuum cleaner 1 to expedite the charging of the secondary battery 43. This helps to prevent premature degradation of the secondary battery 43's lifespan.

[0102] However, the secondary battery 43 has internal resistance. Therefore, if the current value supplied from the secondary battery 43 to the electric blower 14 is reduced, the voltage drop caused by the internal resistance of the secondary battery 43 is correspondingly reduced. As a result, the terminal voltage of the secondary battery 43 can be restored to a certain extent, and the time until the terminal voltage of the secondary battery 43 reaches the discharge termination voltage value can be extended. Therefore, in response to the decrease in the terminal voltage of the secondary battery 43, control is performed to reduce the current value supplied to the electric blower 14.

[0103] Figure 6 This diagram illustrates an example of the contents of the first reference table TB1 used when changing the current value as described above. Additionally, Figure 6 This example illustrates the case when the secondary battery 43 is a new product. The first reference table TB1 registers the magnitudes of the various terminal voltages of the secondary battery 43, corresponding to the current values ​​suitable for supplying to the electric blower 14 at those terminal voltage levels. In the first reference table TB1, the lower the terminal voltage, the lower the corresponding current value. For example, when the terminal voltage of the secondary battery 43 decreases from 20 [V] to 19 [V], the electric blower control unit 74a reduces the current value supplied to the electric blower 14 from 15 [A] to 14 [A].

[0104] (3.3 An example of the control mode of an electric blower)

[0105] Figure 7 This diagram illustrates an example of the control modes of the electric blower 14. In this embodiment, the control modes of the electric blower 14 include "first control," "second control," and "third control." The main unit storage unit 71 stores a first reference table TB1, a "target voltage value" (described later), and a "discharge termination voltage value" in advance.

[0106] exist Figure 7In this context, t11 represents the start time of discharge of the secondary battery 43. t12 represents the moment when the terminal voltage of the secondary battery 43 falls below the "target voltage value" (described later). t13 represents the moment when the current supplied to the electric blower 14 reaches the "lower current limit" (8A in the example above, where it is between 15A and 8A). t14 represents the end time of discharge of the secondary battery 43. Figure 7 For ease of explanation, the voltage drop between terminals t12 and t13 is schematically enlarged to represent the amount of voltage decrease. In this embodiment, "first control" is performed from t11 to t12, "second control" from t12 to t13, and "third control" from t13 to t14. Furthermore, Figure 7 The “discharge termination voltage value” refers to the reference value used to stop the power supply to the electric blower 14 when the terminal voltage of the secondary battery 43 (the voltage value detected by the voltage detection unit 65) is lower than the discharge termination voltage value for a specified time.

[0107] In the "first control," the main unit control unit 74 uses the first reference table TB1 to change the current value supplied to the electric blower 14. For example, the electric blower control unit 74a obtains the terminal voltage value of the secondary battery 43 based on the detection result of the voltage detection unit 65. Then, when the terminal voltage of the secondary battery 43 drops to the voltage value registered in the first reference table TB1, the main unit control unit 74 changes the magnitude of the current supplied to the electric blower 14 to the current value registered in the first reference table TB1 corresponding to the voltage value. As a result, as... Figure 7 As shown, the terminal voltage of the secondary battery 43 decreases while exhibiting a wave-like action.

[0108] In the "second control," the main unit control unit 74 repeatedly performs a predetermined adjustment process to bring the terminal voltage of the secondary battery 43 close to a preset target voltage value. This "prescribed adjustment process" includes, for example, comparing the terminal voltage of the secondary battery 43 detected by the voltage detection unit 65 with the target voltage value at predetermined intervals. If the voltage value detected by the voltage detection unit 65 is lower than the target voltage value, the current supplied from the secondary battery 43 to the electric blower 14 is reduced by a predetermined amount. The predetermined interval is, for example, a time interval of 1 second or less, or a time interval of 10 milliseconds or less. An example of the predetermined interval is 1 millisecond. By performing this process, the terminal voltage of the secondary battery 43 can be stably maintained at a position higher than the discharge termination voltage value, enabling a longer operating time for the electric vacuum cleaner 1. Alternatively, the main unit control unit 74 may skip the "second control" and move to the "third control" after the "first control."

[0109] "Third control" refers to reducing the current supplied to the electric blower 14 to a range of changing current values ​​by performing the aforementioned adjustment processes multiple times in the second control (see reference). Figure 5 Control is performed after the current lower limit value is reached. In the "third control", the process of reducing the current value is stopped. When the "third control" is executed, the terminal voltage of the secondary battery 43 decreases as it discharges. Moreover, if the terminal voltage of the secondary battery 43 falls below the discharge termination voltage value for a predetermined time, the electric blower control unit 74a stops the operation of the electric blower 14.

[0110] (3.4 Determination of the charging time based on the degradation state of the secondary battery)

[0111] (3.4.1 Detection of the deterioration state of secondary batteries)

[0112] Next, the method for determining the power-on time ET based on the degradation state of the secondary battery 43 will be explained. First, the method for detecting the degradation state of the secondary battery 43 will be explained. In this embodiment, the State of Health (SOH) is used as an example of the degradation state of the secondary battery 43. SOH is an example of a degradation parameter.

[0113] First, refer to Figure 8 The changes in characteristics caused by the deterioration of the secondary battery 43 will be explained. When the secondary battery 43 is charged using power supplied from the charging device 8 through constant current control, the rate of change of voltage of the secondary battery 43 per unit time varies depending on the state of harmonics (SOH) of the secondary battery 43.

[0114] Figure 8 This is a diagram used to illustrate the changes in characteristics caused by the deterioration of the secondary battery 43. Figure 8 The relationship between the charging time required for secondary batteries 43 in different deterioration states and the voltage change of secondary batteries 43 after charging begins (characteristic curve).

[0115] like Figure 8 As shown, the more the secondary battery 43 deteriorates, the shorter the charging time required to charge from the specified voltage to the target voltage. In other words, the time width Δt required for the voltage V1 to change from the initial charging voltage to V2 is an example of a characteristic quantity of each characteristic curve. Δt1, Δt2, and Δt3 are examples of the aforementioned time width Δt. The characteristic curve labeled Δt1 shows less deterioration than other characteristic curves. Here, the potential difference between voltage V1 and voltage V2 is called the voltage change (voltage change ΔV), and the rate of change of voltage of the secondary battery 43 per unit time is defined as "ΔV / Δt". Furthermore, in Figure 8For ease of explanation, only three characteristic curves are shown, but in fact, more characteristic curves for each of the multiple degradation states (SOH) are calculated in advance.

[0116] Figure 9 This is a graph representing the second reference table TB2. The second reference table TB2 is a table that records the correspondence between the rate of change of voltage "ΔV / Δt" of the secondary battery 43 per unit time and the state of charge (SOH). Additionally, in... Figure 9 In order to facilitate understanding, the following is used: Figure 8 The relationship between the rate of change of each characteristic curve and the state of harmonics (SOH) of the secondary battery 43 is illustrated. In fact, the rate of change of various voltages of the secondary battery 43, "ΔV / Δt," is categorized in a manner corresponding to a certain level of SOH. The second reference table TB2 is stored in the main unit storage section 71.

[0117] Figure 10 This is a flowchart illustrating the processing flow during the charging of the secondary battery 43. In this embodiment, the state of oxygen (SOH) of the secondary battery 43 is detected during charging. This is because the SOH can be detected with higher accuracy during charging compared to when the secondary battery 43 is discharging (when the electric vacuum cleaner 1 is in use). The reason for this is that, compared to when the electric vacuum cleaner 1 is in use, the current value affecting the secondary battery 43 is smaller or the change in current value is smaller (e.g., constant) during charging. In addition, the secondary battery 43 is undergoing an endothermic chemical reaction, and its temperature is more stable compared to when it is discharging.

[0118] As a specific process, when the status detection unit 74c receives the "charging in progress" information from the secondary battery cell BU, it detects the start of charging of the secondary battery 43 (step SA11). After detecting the start of charging, the status detection unit 74c obtains the time width (Δt) required for charging of a predetermined voltage change (ΔV) based on the detection result of the voltage detection unit 65 (step SA12).

[0119] Here, the characteristic curve of SOH is affected by the temperature of the secondary battery 43. Therefore, in order to improve the detection accuracy of SOH, it is preferable to perform correction based on the temperature of the secondary battery 43. Therefore, the state detection unit 74c corrects the rate of change of voltage (ΔV / Δt) of the secondary battery 43 based on the temperature state of the secondary battery 43 during charging detected by the temperature detection unit 46 and the correction amount preset according to each temperature state of the secondary battery 43 (step SA13).

[0120] Next, the state detection unit 74c compares the rate of change of voltage (ΔV / Δt) of the secondary battery 43, which has been corrected for temperature conditions, with the second reference table TB2 (data table) (step SA14). In detail, the state detection unit 74c first compares the rate of change of voltage (ΔV / Δt) registered in the second reference table TB2 corresponding to "First Level (100% or less and 90% or more)" with the rate of change of voltage (ΔV / Δt) detected during charging of the secondary battery 43, and determines whether the state of harm (SOH) is "First Level" (step SA15). If the rate of change of voltage (ΔV / Δt) registered in the second reference table TB2 corresponding to "First Level" and the rate of change of voltage (ΔV / Δt) detected during charging of the secondary battery 43 are consistent, the state detection unit 74c determines that the SOH of the secondary battery 43 is "First Level" (step SA16).

[0121] On the other hand, if the voltage change rate (ΔV / Δt) registered in the second reference table TB2 corresponding to "First Level" is inconsistent with the voltage change rate (ΔV / Δt) detected during the charging of the secondary battery 43, then the voltage change rate (ΔV / Δt) registered in the second reference table TB2 corresponding to "Second Level (less than 90% and more than 80%)" and the voltage change rate (ΔV / Δt) detected during the charging of the secondary battery 43 are compared to determine whether the SOH is "Second Level" (step SA17). The same process is repeated below (steps SA18 to SA20).

[0122] If the voltage change rate (ΔV / Δt) registered in the second reference table TB2 corresponding to the second lowest "fourth level (less than 70% and more than 60%)" is inconsistent with the voltage change rate (ΔV / Δt) detected during the charging of the secondary battery 43, the SOH is determined to be "fifth level (less than 60%)" (step SA21).

[0123] Next, if the status detection unit 74c has stored historical SOH data in the main unit storage unit 71 (for example, if secondary battery status information BSa is accumulated), it compares the historical SOH data (for example, the latest SOH contained in the historical data) with the newly detected SOH to determine whether the degradation state of the secondary battery 43 exceeds a predetermined amount and thus improves it (step SA23). If the status information generation unit 74d determines that the degradation state of the secondary battery 43 exceeds a predetermined value and has improved it, and assumes that the secondary battery 43 has been replaced, it deletes (initializes) the historical SOH data stored in the main unit storage unit 71 (step SA24).

[0124] On the other hand, if the state information generation unit 74d determines that the deterioration state has not been improved, or if it determines that there is no historical data of SOH in the main unit storage unit 71, it generates secondary battery state information BSa indicating the newly detected SOH, and appends the generated secondary battery state information BSa to the historical data of the secondary battery 43 (step SA25). SOH is an example of "information indicating the state of the secondary battery", and an example of "state indicating the deterioration state of the secondary battery".

[0125] The processes described above, from steps SA11 to SA25, are performed each time the secondary battery 43 is charged. Therefore, each time the secondary battery 43 is charged, the latest SOH value is appended to the historical SOH data stored in the main unit storage unit 71.

[0126] (3.4.2 Determination of energizing time based on SOH)

[0127] Next, the method for determining the energizing time ET based on SOH will be explained.

[0128] Figure 11 This diagram illustrates an example of the contents of the third reference table TB3, which is used to determine the energizing time ET based on the State of Health (SOH). In the third reference table TB3, an appropriate energizing time ET is correspondingly registered for each SOH level of the secondary battery 43. The length of the energizing time ET is established in the third reference table TB3 in a correspondence where the lower the SOH, the shorter the energizing time ET. For example, energizing time ET2 is shorter than energizing time ET1. Energizing time ET3 is shorter than energizing time ET1. Furthermore, Figure 11 The example shown is an example of urging the replacement of the secondary battery 43 without driving the electric vacuum cleaner 1 when the SOH is at level 5.

[0129] Figure 11 The phrase "variable range of current values ​​based on lead angle" indicates the range of current values ​​that can be changed solely by adjusting the lead angle θ, given various energizing times ET (ET1 to ET4). For example... Figure 11 As shown, the shorter the energizing time ET, the lower the lower limit of the variable current value range can be reduced. Furthermore, the "variable current value range based on the lead angle" may not actually be registered in the third reference table TB3.

[0130] Figure 12 This is a flowchart illustrating the process of using the electric vacuum cleaner 1. First, the main unit control unit 74 detects the user's operation of turning on the power to the electric vacuum cleaner 1 via the operation unit 16 (step SA31).

[0131] Next, the power-on time determination unit 74e determines whether historical data on the state of harm (SOH) of the secondary battery 43 exists in the main unit storage unit 71 (step SA32). If historical data on the SOH exists in the main unit storage unit 71, the power-on time determination unit 74e determines the power-on time ET corresponding to the most recent SOH based on the most recent SOH contained in the historical data stored in the main unit storage unit 71 and the third reference table TB3 (step SA33). On the other hand, if historical data on the SOH does not exist in the main unit storage unit 71, the power-on time determination unit 74e determines the power-on time ET based on a preset initial value (step SA34).

[0132] Furthermore, the term "recent SOH" is not limited to the last detected SOH (the latest SOH). It can also be the average (including weighted averages) of multiple SOHs detected within a specified period (e.g., one month) immediately preceding the current time (the time of execution of step SA33), obtained by performing a prescribed statistical process on the multiple SOHs detected within the aforementioned specified period. Additionally, the "recent SOH" can also be the lowest among the multiple SOHs detected within the aforementioned specified period. Based on these configurations, even if there are errors in the SOH detection, the impact of those errors can be reduced.

[0133] In this embodiment, the power-on time determination unit 74e determines the power-on time ET before starting the drive of the electric blower 14. Moreover, the power-on time ET will not be changed as long as the operation unit 16 receives an operation from a user to disconnect the power to the electric vacuum cleaner 1, or if the operation unit 16 does not receive an operation from a user to change the drive mode of the electric vacuum cleaner 1 ("strong mode" and "weak mode", etc.).

[0134] Next, the electric blower control unit 74a starts discharging the secondary battery 43 based on the energizing time ET determined by the energizing time determination unit 74e (step SA35). Then, the electric blower control unit 74a monitors the terminal voltage of the secondary battery 43 detected by the voltage detection unit 65, and performs the aforementioned "first control," "second control," and "third control" based on the terminal voltage of the secondary battery 43. In this embodiment, the electric blower control unit 74a changes the current value in the aforementioned "first control" and "second control" by changing the lead angle θ of the electric blower 14. According to this control, the current value is changed only by the lead angle θ, thus simplifying the control.

[0135] Furthermore, the electric blower control unit 74a, for example, ends the discharge of the secondary battery 43 (step SA36) when the operation unit 16 receives an operation from the user to disconnect the power of the electric vacuum cleaner 1.

[0136] (4. Advantages)

[0137] In this embodiment, a main unit control unit 74 is provided to determine the power-on time ET based on information indicating the state of the secondary battery 43. With this configuration, an appropriate power-on time ET can be determined according to the state of the secondary battery 43. Therefore, when the output voltage of the secondary battery 43 is prone to decrease due to its state, shortening the power-on time ET can reduce the current value of the discharge current from the secondary battery 43. If the current value of the discharge current from the secondary battery 43 can be reduced, the voltage drop caused by the internal resistance of the secondary battery 43 can be suppressed at least in proportion to the amount of current reduction. Therefore, even when the output voltage of the secondary battery 43 is prone to decrease due to deterioration, it is easier to maintain a higher terminal voltage of the secondary battery 43. For example, even when there is a limit to the range of current value variation based on the lead angle θ, it is easier to maintain a higher terminal voltage of the secondary battery 43 when the output voltage of the secondary battery 43 is prone to decrease. Therefore, the secondary battery 43 can be depleted to a lower level of remaining capacity. Therefore, the operation of the electric blower 14 can continue, ensuring the operating time of the electric vacuum cleaner 1.

[0138] In this embodiment, the power-on time determination unit 74e determines the power-on time ET before starting the operation of the electric vacuum cleaner 1, and drives the electric vacuum cleaner 1 based on the determined power-on time ET. Furthermore, during the operation of the electric vacuum cleaner 1, the current value supplied to the electric blower 14 is changed only by adjusting the lead angle θ. With this configuration, since an appropriate power-on time ET corresponding to the state of the secondary battery 43 is initially determined, the current value supplied to the electric blower 14 can be changed only by adjusting the lead angle θ while maintaining a high terminal voltage of the secondary battery 43. This simplifies control and contributes to the cost reduction of the electric vacuum cleaner 1.

[0139] In this embodiment, the main unit control unit 74 determines the power-on time ET for the use of the electric vacuum cleaner 1 after the charging time based on information indicating the state of the secondary battery 43 detected during charging. According to this configuration, the power-on time ET is determined based on information detected during charging of the secondary battery 43, which is more stable than during the use of the electric vacuum cleaner 1. Therefore, a power-on time ET more suitable for the state of the secondary battery 43 can be determined. Furthermore, the detection of the state of the secondary battery 43, such as SOH, can be performed during use, not during charging.

[0140] In this embodiment, the main unit control unit 74 determines the power-on time ET based on information indicating the degradation state of the secondary battery 43 (e.g., SOH). Here, if the degradation state of the secondary battery 43 worsens, its internal resistance increases, and the terminal voltage of the secondary battery 43 tends to decrease. However, according to this embodiment, an appropriate power-on time ET can be determined based on the degradation state of the secondary battery 43. Therefore, even if the secondary battery 43 is degraded, the electric blower 14 can continue to be driven, ensuring the operating time of the electric vacuum cleaner 1.

[0141] Next, several variations of the first embodiment will be described. Furthermore, in each variation, the configuration is the same as the first embodiment described above, except as described below.

[0142] (First variation of the first embodiment)

[0143] The first variation is an example of determining the power-on time ET based on the state of state (SOH) and the temperature state of the secondary battery 43. The impact of the degradation state of the secondary battery 43 varies depending on the temperature of the secondary battery 43. When the temperature of the secondary battery 43 is relatively high, it is less affected by the degradation state. On the other hand, when the temperature of the secondary battery 43 is relatively low, it is more susceptible to degradation. Therefore, in this variation, the power-on time ET is determined based on the most recent SOH and the temperature of the secondary battery 43 detected during the use of the electric vacuum cleaner 1.

[0144] Figure 13 This is a diagram illustrating an example of the contents of reference table TB3a in the first variation. In this variation, reference table TB3a, for example, categorizes each SOH level into three temperature states: "low temperature," "medium temperature," and "high temperature," and pre-registers the energizing time ET for each temperature state. For example, the energizing times ET1a, ET2a, ET3a, and ET4a at low temperature are shorter than the energizing times ET1, ET2, ET3, and ET4 at medium temperature. On the other hand, the energizing times ET1b, ET2b, ET3b, and ET4b at high temperature are the opposite.

[0145] The power-on time determination unit 74e determines the power-on time ET based on reference table TB3a, the most recent SOH contained in historical data, and information indicating the temperature state of the secondary battery 43 detected by the temperature detection unit 46. In addition, "information indicating the temperature state of the secondary battery 43" refers to, for example, information on the temperature state detected immediately before the start of driving the electric vacuum cleaner 1 at the beginning of this use of the electric vacuum cleaner 1 (for example, after step SA31).

[0146] Based on this configuration, the main unit control unit 74 can determine a more appropriate power-on time ET based on information indicating the degradation state of the secondary battery 43 and information indicating the temperature state of the secondary battery 43. Furthermore, "determining the power-on time ET based on information indicating the degradation state of the secondary battery 43 and information indicating the temperature state of the secondary battery 43" is not limited to the method based on reference table TB3a; it can also be achieved by correcting a temporarily determined power-on time ET based on information indicating the temperature state of the secondary battery 43.

[0147] (Second variation of the first embodiment)

[0148] The second variation is an example of determining the power-on time ET based on information supplied from the secondary battery unit BU (e.g., secondary battery status information BSb). In the second variation, the secondary battery unit control unit 53 of the secondary battery unit BU detects the state of emergency (SOH) inside the secondary battery unit BU. The method for detecting the SOH is, for example, the same as in the first embodiment. The secondary battery unit control unit 53 sends the secondary battery status information BSb indicating the detected SOH to the main unit control unit 74. The main unit control unit 74 appends the secondary battery status information BSb sent from the secondary battery unit communication unit 52 to the historical SOH data stored in the main unit storage unit 71. Then, the power-on time determination unit 74e determines the power-on time ET based on the most recent SOH (the SOH detected by the secondary battery unit control unit 53) contained in the historical data.

[0149] (Third variation of the first embodiment)

[0150] The third variation is an example of processing the fully charged voltage value of the secondary battery 43, which is changed by the secondary battery unit BU, as information representing the state of the secondary battery 43.

[0151] Figure 14 This is a diagram showing reference table TB4 for the third modified example. Reference table TB4 records the fully charged voltage values ​​(limiting voltages) applied before and after the secondary battery 43 deteriorates. The fully charged voltage value (limiting voltage) refers to the voltage at which charging stops when the battery has been charged to that value. Reference table TB4 is stored in the secondary battery cell storage unit 51. The secondary battery cell control unit 53 detects the state of equilibrium (SOH), and if the SOH exceeds a predetermined threshold, it reduces the fully charged voltage value of the secondary battery 43 based on reference table TB4. This provides more reliable protection for the secondary battery 43. Figure 14 In the example, OCV1 had a value of 4.0 [V]. OCV2 had a value of 3.8 [V].

[0152] In this modified example, the main unit control unit 74 can indirectly detect the degradation state of the secondary battery 43, for example, by detecting the terminal voltage of the secondary battery 43 when it is fully charged during charging. In this case, the information indicating the indirectly detected degradation state of the secondary battery 43 is stored as historical data of the secondary battery 43 in the main unit storage unit 71, for example, for determining the power-on time ET of the electric vacuum cleaner 1 for the next use.

[0153] (Fourth variation of the first embodiment)

[0154] In the fourth variation, the state of equilibrium (SOH) is detected based on the cumulative time from a certain voltage state to the discharge termination voltage. Here, as the SOH decreases, the rechargeable capacity (charge amount) decreases. Therefore, the discharge time from a certain voltage state to the discharge termination voltage also shortens due to increased degradation. Therefore, in this variation, the focus is on the discharge time from a certain voltage state to the discharge termination voltage. Furthermore, when the discharge time is divided into multiple operations, for example, the cumulative value (cumulative time) of the discharge time from a certain voltage state to the discharge termination voltage can be used. In this variation, the state detection unit 74c detects SOH based on the discharge time (e.g., its cumulative time) from the voltage state to the discharge termination voltage. In this case, information indicating the detected SOH is stored as historical data of the secondary battery 43 in the main unit storage unit 71, for example, for determining the power-on time ET during the next use of the electric vacuum cleaner 1.

[0155] Furthermore, in the first embodiment, the degradation state of the secondary battery 43 is not limited to SOH. For example, the degradation state of the secondary battery 43 can also be determined based on the voltage drop curve ZA following the voltage drop immediately after the start of discharge (see reference). Figure 15 The shape of the voltage drop curve ZA can be used to infer the state of the secondary battery 43. Therefore, the state detection unit 74c can also generate information indicating the deterioration state of the secondary battery 43 based on the shape of the voltage drop curve ZA. In this case, the information indicating the generated deterioration state of the secondary battery 43 is stored as historical data of the secondary battery 43 in the main unit storage unit 71, for example, for determining the power-on time ET when the electric vacuum cleaner 1 is used next.

[0156] (Second Implementation)

[0157] Next, the electric vacuum cleaner 1 according to the second embodiment will be described. The difference between the second embodiment and the first embodiment is that the power-on time determination unit 74e determines the power-on time ET based on the internal resistance of the secondary battery 43 instead of SOH. Otherwise, the configuration is the same as the first embodiment, except as described below.

[0158] First, the method for detecting the internal resistance of the secondary battery 43 will be explained.

[0159] Figure 15 This is a diagram illustrating the method for detecting the internal resistance of secondary battery 43. Figure 15 The diagram shows the changes in terminal voltage of the secondary battery 43 before and after the start of discharge and before and after the end of discharge. When the secondary battery 43 begins to discharge, a voltage drop occurs corresponding to the magnitude of its internal resistance. Conversely, at the end of discharge, the opposite phenomenon occurs.

[0160] In this embodiment, the state detection unit 74c detects the internal resistance of the secondary battery 43 as the state of the secondary battery 43. For example, the state detection unit 74c detects the internal resistance of the secondary battery 43 based on at least one of the change in the terminal voltage of the secondary battery 43 before and after the start of discharge and the change in the terminal voltage of the secondary battery 43 before and after the end of discharge. In the former case, the state detection unit 74c, for example, is based on the change in the terminal voltage of the secondary battery 43 before and after the start of discharge detected by the voltage detection unit 65 (…). Figure 15 The internal resistance of the secondary battery 43 is detected by the current value detected by the first current detection unit 66 and / or the second current detection unit 67 after the start of discharge (VA1-VB1). In the latter case, the state detection unit 74c is based, for example, on the change in terminal voltage of the secondary battery 43 before and after the end of discharge detected by the voltage detection unit 65 (VA1-VB1). Figure 15 The internal resistance of the secondary battery 43 is detected by measuring the current value before the end of discharge, which is detected by the first current detection unit 66 and / or the second current detection unit 67 (VA2-VB2) in the secondary battery.

[0161] Figure 16 This diagram illustrates an example of the contents of reference table TB5, which is used to determine the energizing time ET based on the internal resistance of the secondary battery 43. In reference table TB5, an appropriate energizing time ET is correspondingly registered for each value of the internal resistance of the secondary battery 43. Reference table TB5 establishes a correspondence between the lengths of the energizing time ET and the internal resistance of the secondary battery 43, with the latter corresponding to a shorter energizing time ET. For example, energizing time ET2 is shorter than energizing time ET1. Energizing time ET3 is shorter than energizing time ET2.

[0162] Figure 17 This is a flowchart illustrating the process of using the electric vacuum cleaner 1. First, the main unit control unit 74 detects the user's operation of turning on the power to the electric vacuum cleaner 1 via the operation unit 16 (step SB11).

[0163] Next, the power-on time determination unit 74e determines whether historical data on the internal resistance of the secondary battery 43 exists in the main unit storage unit 71 (step SB12). If historical data on the internal resistance of the secondary battery 43 exists in the main unit storage unit 71, the power-on time determination unit 74e determines the power-on time ET corresponding to the most recent internal resistance of the secondary battery 43 stored in the historical data in the main unit storage unit 71 and reference table TB5 (step SB13). On the other hand, if historical data on the internal resistance of the secondary battery 43 does not exist in the main unit storage unit 71, the power-on time determination unit 74e determines the power-on time ET based on a preset initial value (step SB14).

[0164] Furthermore, the term "recent internal resistance" is not limited to the last detected internal resistance (the latest internal resistance). For example, it could be the average of the internal resistance of the secondary battery 43 detected based on the change in terminal voltage of the secondary battery 43 before and after the start of discharge, and the internal resistance of the secondary battery 43 detected based on the change in terminal voltage of the secondary battery 43 before and after the end of discharge. Additionally, "recent internal resistance" could also be the average of multiple internal resistance values ​​detected within a specified period (e.g., one month) immediately preceding the current time (the time of execution of step SB13), including weighted averages, obtained by performing a prescribed statistical processing on the values ​​of multiple internal resistances detected within the aforementioned specified period. Furthermore, "recent internal resistance" could also be the largest internal resistance among the multiple internal resistances detected within the aforementioned specified period. Based on these configurations, even if there is an error in the detection of the internal resistance, the impact of that error can be minimized.

[0165] Next, the electric blower control unit 74a controls the first switch unit 63 to supply power to the electric blower 14 based on the power-on time ET determined by the power-on time determination unit 74e, and starts discharging the secondary battery 43 (step SB21). Correspondingly, vacuuming is performed by the user using the electric vacuum cleaner 1.

[0166] At this time, the state detection unit 74c detects the internal resistance of the secondary battery 43, for example, based on the change in terminal voltage of the secondary battery 43 before and after the start of discharge detected by the voltage detection unit 65, and the current value after the start of discharge detected by the first current detection unit 66 and / or the second current detection unit 67 (step SB22). Specifically, when the secondary battery 43 starts discharging, the state detection unit 74c causes the voltage detection unit 65 to detect the terminal voltage of the secondary battery 43 before the start of discharge, and causes the voltage detection unit 65 to detect the terminal voltage of the secondary battery 43 at a time when a predetermined time (e.g., the time required for the voltage fluctuation to stabilize within a certain range) has elapsed since the start of the discharge of the secondary battery 43, and detects the internal resistance of the secondary battery 43 based on their detection results.

[0167] Here, the internal resistance of the secondary battery 43 is affected by the temperature of the secondary battery 43 and its remaining capacity. Therefore, to further improve the detection accuracy of the internal resistance, it is preferable to perform correction based on the temperature and remaining capacity of the secondary battery 43. Therefore, the state detection unit 74c corrects the detected internal resistance of the secondary battery 43 based on information indicating the temperature state of the secondary battery 43 at the start of discharge detected by the temperature detection unit 46, and a correction amount preset according to each temperature state of the secondary battery 43 (step SB23). In addition, the state detection unit 74c corrects the detected internal resistance of the secondary battery 43 based on information indicating the terminal voltage of the secondary battery 43 before the start of discharge detected by the voltage detection unit 65, and a correction amount preset according to each terminal voltage of the secondary battery 43 (the remaining capacity of the secondary battery 43) (step SB23). Alternatively, only correction based on the temperature state of the secondary battery 43 or correction based on the remaining capacity of the secondary battery 43 may be performed.

[0168] Then, the status information generation unit 74d generates secondary battery status information BSa representing the corrected internal resistance of the secondary battery 43, and appends the generated secondary battery status information BSa to the historical data of the secondary battery 43. Furthermore, similar to the first embodiment, the main unit control unit 74 compares the historical data of the internal resistance of the secondary battery 43 stored in the main unit storage unit 71 with the newly detected internal resistance of the secondary battery 43, determines whether the degradation state of the secondary battery 43 exceeds a predetermined amount, and improves it accordingly. If it is determined that the degradation state of the secondary battery 43 exceeds the predetermined amount and has been improved, and the secondary battery 43 has been replaced, the historical data of the internal resistance of the secondary battery 43 stored in the main unit storage unit 71 is deleted (initialized). This is also the same as the case where the internal resistance of the secondary battery 43 is detected at the end of discharge.

[0169] Next, the electric blower control unit 74a detects the user's operation of disconnecting the power supply to the electric vacuum cleaner 1 via the operation unit 16. In this case, the electric blower control unit 74a controls the first switch unit 63 to stop the power supply to the electric blower 14, thereby ending the discharge of the secondary battery 43 (step SB31).

[0170] At this time, the state detection unit 74c detects the internal resistance of the secondary battery 43, for example, based on the change in terminal voltage of the secondary battery 43 before and after the end of discharge detected by the voltage detection unit 65, and the current value before the end of discharge detected by the first current detection unit 66 and / or the second current detection unit 67 (step SB32). Specifically, when the discharge of the secondary battery 43 ends, the state detection unit 74c causes the voltage detection unit 65 to detect the terminal voltage of the secondary battery 43 before the end of the discharge, and causes the voltage detection unit 65 to detect the terminal voltage of the secondary battery 43 at a time when a predetermined time (e.g., the time required for the voltage fluctuation to stabilize within a certain range) has elapsed since the end of the discharge of the secondary battery 43, and detects the internal resistance of the secondary battery 43 based on their detection results.

[0171] Next, similarly to step SB23, the state detection unit 74c corrects the detected internal resistance of the secondary battery 43 based on its temperature and remaining capacity (step SB33). In this case, the "temperature state at the start of discharge" and "terminal voltage before the start of discharge" in step SB33 are replaced with the "temperature state at the end of discharge" and "terminal voltage after the end of discharge," respectively. Alternatively, only the correction based on the temperature state of the secondary battery 43 or the correction based on its remaining capacity may be performed.

[0172] Alternatively, one of the following can be performed: detecting the internal resistance based on the change in terminal voltage of the secondary battery 43 before and after the start of discharge (steps SB22 and SB23) or detecting the internal resistance based on the change in terminal voltage of the secondary battery 43 before and after the end of discharge (steps SB32 and SB33).

[0173] In the embodiment described above, the main unit control unit 74 determines the power-on time ET for the current use of the electric vacuum cleaner 1 based on information indicating the state of the secondary battery 43 detected during the previous use of the electric vacuum cleaner 1. This simplifies control compared to detecting the state of the secondary battery 43 after the start of operation and adjusting the power-on time ET accordingly.

[0174] In this embodiment, the main unit control unit 74 determines the power-on time ET based on information indicating the internal resistance of the secondary battery 43. With this configuration, an appropriate power-on time ET corresponding to the internal resistance of the secondary battery 43 can be determined directly based on the internal resistance of the secondary battery 43. Therefore, even when the internal resistance of the secondary battery 43 is high, the electric blower 14 can continue to be driven, ensuring the operating time of the electric vacuum cleaner 1.

[0175] Here, the internal resistance of the secondary battery 43 is less affected when the temperature of the secondary battery 43 is high, and is more easily affected when the temperature of the secondary battery 43 is low. In this embodiment, the state detection unit 74c detects the internal resistance of the secondary battery 43 based on the change in the terminal voltage of the secondary battery 43 at the start of discharge. With this configuration, the internal resistance of the secondary battery 43 can be detected before its temperature rises. That is, the internal resistance of the secondary battery 43 can be detected even when its internal resistance is significantly affected. Therefore, the internal resistance of the secondary battery 43 can be detected with higher accuracy.

[0176] In this embodiment, the state detection unit 74c detects the internal resistance of the secondary battery 43 based on the change in the terminal voltage of the secondary battery 43 at the end of discharge. With this configuration, the internal resistance of the secondary battery 43 can be detected even after the secondary battery 43 has been fully discharged. Therefore, the latest internal resistance of the secondary battery 43 can be detected.

[0177] In this embodiment, the state detection unit 74c detects the internal resistance of the secondary battery 43 based on the change in the terminal voltage of the secondary battery 43 at the start of discharge, and also detects the internal resistance of the secondary battery 43 based on the change in the terminal voltage of the secondary battery 43 at the end of discharge. With this configuration, the internal resistance of the secondary battery 43 can be detected based on various states (e.g., various temperatures). Therefore, a more suitable energizing time ET corresponding to the internal resistance of the secondary battery 43 can be determined.

[0178] Next, several variations of the second embodiment will be described. Furthermore, in each variation, the configuration is the same as that of the second embodiment described above, except as described below.

[0179] (First variation of the second embodiment)

[0180] The first variation is an example where the power-on time ET is determined based on the internal resistance and temperature of the secondary battery 43. As described above, the internal resistance of the secondary battery 43 varies depending on its temperature. When the temperature of the secondary battery 43 is relatively high, the internal resistance decreases. On the other hand, when the temperature of the secondary battery 43 is relatively low, the internal resistance increases. Therefore, in this variation, the power-on time ET is determined based on the most recent internal resistance and the temperature state of the secondary battery 43 detected during this use of the electric vacuum cleaner 1.

[0181] Figure 18 This is a diagram representing reference table TB5a for the first variation. In this variation, reference table TB5a, for example, divides each internal resistor into three temperature states: "low temperature," "medium temperature," and "high temperature," and pre-registers the appropriate energizing time ET for each temperature state. The energizing times ET1c, ET2c, ET3c, and ET4c at low temperature are shorter than the energizing times ET1, ET2, ET3, and ET4 at medium temperature. On the other hand, the energizing times ET1d, ET2d, ET3d, and ET4d at high temperature are the opposite.

[0182] The power-on time determination unit 74e determines the power-on time ET based on reference table TB5a, the most recent internal resistance contained in historical data stored in the main unit storage unit 71, and information indicating the temperature state of the secondary battery 43 detected by the temperature detection unit 46. Furthermore, the "information indicating the temperature state of the secondary battery 43" refers, for example, to the temperature state detected by the temperature detection unit 46 immediately before the start of the current use of the electric vacuum cleaner 1 (after step SB11).

[0183] Based on this configuration, the main unit control unit 74 can determine a more appropriate energizing time ET based on information indicating the internal resistance of the secondary battery 43 and information indicating the temperature state of the secondary battery 43. Furthermore, "determining the energizing time ET based on information indicating the internal state of the secondary battery 43 and information indicating the temperature state of the secondary battery 43" is not limited to the method based on reference table TB5a; it can also be achieved by correcting a temporarily determined energizing time ET based on information indicating the temperature state of the secondary battery 43.

[0184] (Second variation of the second embodiment)

[0185] The second variation is an example where the power-on time ET is determined based on the internal resistance of the secondary battery 43 and its remaining capacity. As described above, the internal resistance of the secondary battery 43 varies depending on its remaining capacity. When the remaining capacity of the secondary battery 43 is relatively high, the internal resistance decreases. On the other hand, when the remaining capacity of the secondary battery 43 is relatively low, the internal resistance increases. Therefore, in this variation, the power-on time ET is determined based on the most recent internal resistance and the remaining capacity of the secondary battery 43 (terminal voltage of the secondary battery 43) detected during this use of the electric vacuum cleaner 1.

[0186] Figure 19 This is a diagram representing reference table TB5b for the second variation. In this variation, reference table TB1e, for example, divides each internal resistor into three states of remaining capacity: "Remaining Capacity: Low," "Remaining Capacity: Medium," and "Remaining Capacity: High," and pre-registers the appropriate energizing time ET for each state of remaining capacity. The energizing times ET1e, ET2e, ET3e, and ET4e for "Remaining Capacity: Low" are shorter than the energizing times ET1, ET2, ET3, and ET4 for "Remaining Capacity: Medium." On the other hand, the energizing times ET1f, ET2f, ET3f, and ET4f for "Remaining Capacity: High" are the opposite.

[0187] The power-on time determination unit 74e determines the power-on time ET based on reference table TB5, the most recent internal resistance contained in the historical data stored in the main unit storage unit 71, and information indicating the terminal voltage of the secondary battery 43 detected by the voltage detection unit 65. In addition, "terminal voltage of the secondary battery 43" refers, for example, to the terminal voltage detected by the voltage detection unit 65 immediately before the start of driving the electric vacuum cleaner 1 at the beginning of this use (for example, after step SB11).

[0188] Based on this configuration, the main unit control unit 74 can determine a more appropriate power-on time ET based on information indicating the internal resistance of the secondary battery 43 and information indicating the remaining capacity of the secondary battery 43. Furthermore, "determining the power-on time ET based on information indicating the internal state of the secondary battery 43 and information indicating the remaining capacity of the secondary battery 43" is not limited to the method based on reference table TB5b; it can also be achieved by correcting a temporary power-on time ET based on information indicating the remaining capacity of the secondary battery 43.

[0189] (Third variation of the second embodiment)

[0190] The third variation is an example in which the power-on time ET is determined by switching between the state of equilibrium (SOH) and the internal resistance. In this variation, the state of the secondary battery 43 is detected as information indicating its state, just as in the first embodiment, and the internal resistance of the secondary battery 43 is detected as in the second embodiment, and these are stored as historical data in the main unit storage unit 71.

[0191] In this modified example, the power-on time determination unit 74e determines the power-on time ET based on the historical data of the internal resistance (SOH) during the period until the amount of historical data accumulated in the main unit storage unit 71 exceeds a certain threshold. This is because the detection error of the internal resistance is larger than that of the SOH, so determining the power-on time ET based on the SOH is more effective when the amount of historical data accumulated is small. On the other hand, the internal resistance is a physical quantity that can predict the voltage drop in the secondary battery 43 with higher accuracy than the SOH. Therefore, after the power-on time determination unit 74e accumulates the historical data of the internal resistance in the main unit storage unit 71 to the amount exceeding a certain threshold, it determines the power-on time ET based on the historical data of the internal resistance instead of the SOH. As a result, a more suitable power-on time ET can be determined.

[0192] (Third Implementation)

[0193] Next, the electric vacuum cleaner 1 according to the third embodiment will be described. The third embodiment differs from the first embodiment in that the power-on time determination unit 74e determines the power-on time ET based on the temperature of the secondary battery 43, independent of the state of equilibrium (SOH) or internal resistance. Otherwise, the configuration is the same as the first embodiment, except as described below.

[0194] Figure 20 This is a diagram showing reference table TB6 of the third embodiment. In this embodiment, reference table TB6 is divided into three temperature states, for example, "low temperature", "medium temperature" and "high temperature", and the energizing time ET suitable for each temperature state is pre-registered. For example, the energizing time ET2 at medium temperature is shorter than the energizing time ET1 at high temperature. The energizing time ET3 at low temperature is shorter than the energizing time ET2 at medium temperature.

[0195] In this embodiment, the power-on time determination unit 74e determines the power-on time ET of the electric vacuum cleaner 1 for the current use, for example, based on information indicating the temperature detected by the temperature detection unit 46 before the discharge of the secondary battery 43 begins during the current use of the electric vacuum cleaner 1, and reference table TB6. With this configuration, a more appropriate power-on time ET corresponding to the temperature of the secondary battery 43 can be determined.

[0196] The above describes several implementation methods and their variations, but the implementation methods are not limited to the examples described above. For example, the first to third implementation methods and their variations can also be combined with each other.

[0197] Furthermore, the power-on time determination unit 74e can also determine the power-on time ET in the second operating mode based on information indicating the state of the secondary battery 43 detected in the first operating mode (e.g., information indicating deterioration or information indicating internal resistance) when the operation unit 16 receives a user's operation to switch from a first operating mode (e.g., "weak mode") to a second operating mode with a relatively higher rotation speed (e.g., "strong mode"). With this configuration, the power-on time ET of the second operating mode with a higher rotation speed (higher current value) can be appropriately set according to the immediate state of the secondary battery 43.

[0198] Furthermore, in the various embodiments and modifications described above, the main unit control unit 74 may change the lead angle θ instead of changing the energizing time ET based on information indicating the state of the secondary battery 43, or it may change the lead angle θ in addition to changing the energizing time ET based on information indicating the state of the secondary battery 43. The main unit control unit 74 may also change the magnitude of the current by changing at least one of the energizing time ET and the lead angle θ.

[0199] (Fourth Implementation)

[0200] Next, the electric vacuum cleaner 1 according to the fourth embodiment will be described. The configuration of the electric blower (motor) and the accompanying control in the fourth embodiment are different from those in the embodiments described above. However, the configuration is the same as that in the first embodiment, except for the following description.

[0201] First, let's explain the electric blower 14A.

[0202] Figure 21 This is a schematic diagram illustrating the electric blower 14A. Additionally, in Figure 21 For the sake of simplicity, a model of a bipolar electric blower 14A is shown. Electric blower 14A corresponds to the electric blower 14 described above. Electric blower 14A can also be a three-pole or higher electric blower, similar to electric blower 14.

[0203] An electric blower 14A, for example, includes a first stator coil LA, a second stator coil LB, a rotor RT, and a position detector PD. The first stator coil LA and the second stator coil LB are configured, for example, in a pole-pole relationship. The first stator coil LA and the second stator coil LB are electrically connected in series, and the orientation of the windings is determined by the increase in the strength of the magnetic field generated when energized. The position detector PD is, for example, positioned corresponding to the stator coil LB. The position detector PD detects the position (phase) of the rotor RT by detecting the polarity of the nearest pole of the rotor RT. Figure 21 In the state shown, the position detector PD detects the S pole. This electric blower 14A is an example of a brushless motor (permanent magnet synchronous motor, reluctance motor). The stator coil of the electric blower 14A is single-phase, but it is not limited to this and can also be multi-phase. The following description is for the bipolar and single-phase type.

[0204] Figure 22 Is with Figure 21 The timing diagram corresponding to the model of the electric blower 14A shown. Figure 22 In the attached diagram, reference numeral T indicates the period of one revolution of the electric blower 14A. One cycle is the period from time tM11 to time tM21. Similarly, one cycle is the period from time tM12 to time tM22. Figure 22 In the example shown, time passes in the order of tM11, tM12, tM21, and tM22. The rotor RT of the electric blower 14A rotates at a specified speed corresponding to the period T.

[0205] Reference Figure 22 In section (a) and (c), explanations are provided for cases where there is no adjustment amount based on the adjustment element (the case where the lead angle θ is zero). Figure 22 (a) shows the energizing mode, and (c) shows the polarity detected by the position detector PD. At time tM11, the position detector PD detects the N pole instead of the S pole. Based on the detection result of the position detector PD, the main unit control unit 74 starts energizing the stator coils LA and LB in the first direction at time tM11, and stops energizing the stator coils LA and LB after a predetermined time ETA. Similarly, at time tM12, the position detector PD detects the S pole instead of the N pole. Based on the detection result of the position detector PD, the main unit control unit 74 starts energizing the stator coils LA and LB in the second direction at time tM12, and stops energizing the stator coils LA and LB after a predetermined time ETB. If these predetermined times ETA and ETB are extended, the current value supplied to the electric blower 14A increases. Figure 22The specified time ETA and specified time ETB can be of the same length, and they are referred to as the energizing time ET.

[0206] Figure 22 (b) is an example of an energizing mode in the case of an adjustment amount based on the adjustment element (in the case of a lead angle θ). Figure 22 The power-on mode in (b) is the same as Figure 22 The energizing mode shown in (a) has a phase difference with a leading angle θ.

[0207] Next, the control elements that can be applied to the control of the electric blower 14A will be explained.

[0208] Among the aforementioned control elements are the energizing time ET, lead angle θ, freewheeling time FWT, freewheeling angle, duty cycle DF, or the frequency PF of the pulse signal used to control the energizing of the electric blower 14A, which are related to the driving of the electric blower 14A.

[0209] The control elements other than the energizing time and lead angle mentioned above will be explained in turn.

[0210] like Figure 22 As shown, the freewheeling time FWT is defined as the length of the period from the end of the first energizing time ET to the beginning of the next second energizing time ET.

[0211] The freewheeling angle is defined based on the energizing time ET and the freewheeling time FWT. For example, the freewheeling angle is calculated based on the following formula.

[0212] (Freewheeling time FWT) / (Power-on time ET + Freewheeling time FWT)

[0213] The duty cycle DF is the ratio of the energizing period (energizing time ET) to the cycle T associated with the drive of the electric blower 14A. For example, it is preferable to specify the duty cycle DF using the formula shown below.

[0214] One of the following formulas: (Electrification time ET / period T), (Specified time ETA / period T), (Specified time ETB / period T), (Electrification time ET×2 / period T), or ((Specified time ETA+Specified time ETB) / period T).

[0215] The control elements described above are an example of control elements relating to PWM (pulse width modulation) control with a fixed period T. These control elements can also be applied to the control of the various embodiments described above.

[0216] (Common variations of the implementation method)

[0217] In the first to fourth embodiments, examples of PWM control with a fixed period T were described. In this modified example, PFM (Pulse Frequency Modulation) control, which varies the period T, will be described. In PFM control, the width (energizing time) of the pulse signal used to control the energization of the electric blower 14A is not changed, but the repetition frequency (period) of the pulses in the pulse signal is changed to obtain the desired control quantity. For example, the main unit control unit 74 frequency modulates the control quantity that drives the electric blower 14A, thereby changing the frequency or period of the aforementioned pulse signal sequentially. In this way, the main unit control unit 74 can also control the electric blower 14A and drive it by means of PFM control instead of the aforementioned PWM control.

[0218] According to at least one embodiment described above, the electric vacuum cleaner determines the magnitude of control elements related to the power supplied from the secondary battery to the electric blower based on information indicating the state of the secondary battery, so that even if the output voltage of the secondary battery 43 is prone to decrease, the electric blower can continue to be driven, ensuring the operating time.

[0219] Several embodiments of the present invention have been described, but these embodiments are provided by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, and likewise within the scope of the invention as described in the claims and its equivalents.

[0220] Below are some examples of electric vacuum cleaners.

[0221] [1] An electric vacuum cleaner, comprising:

[0222] Electric motor;

[0223] A secondary battery supplies power to the electric motor; and

[0224] The control unit determines the magnitude of control elements related to the power supplied from the secondary battery to the motor based on information indicating the state of the secondary battery.

[0225] [2] In the electric vacuum cleaner as described in [1],

[0226] The control unit,

[0227] The control elements are determined as the energizing time, lead angle, freewheeling time, freewheeling angle, duty cycle related to the energizing period of the motor windings relative to the repetition period, or the modulation frequency of the pulse signal used to control the energizing, and the magnitude of the determined control elements is determined.

[0228] [3] In the electric vacuum cleaner as described in [1],

[0229] The control unit determines the magnitude of the control element when the electric vacuum cleaner is used after the charging time based on information indicating the state of the secondary battery detected during charging.

[0230] [4] In the electric vacuum cleaner as described in [1] or [2],

[0231] The control unit determines the magnitude of the control element for the current use of the electric vacuum cleaner based on information indicating the state of the secondary battery detected during the last use of the electric vacuum cleaner.

[0232] [5] In any of the electric vacuum cleaners described in [1] to [3],

[0233] The control unit can drive the motor in a first operating mode and a second operating mode with a higher speed than the first operating mode. When switching from the first operating mode to the second operating mode, it determines the magnitude of the control element in the second operating mode based on information indicating the state of the secondary battery detected in the first operating mode.

[0234] [6] In any of the electric vacuum cleaners described in any of [1] to [4],

[0235] The information indicating the state of the secondary battery includes information indicating the degradation state of the secondary battery.

[0236] The control unit determines the magnitude of the control element based on information indicating the degradation state of the secondary battery.

[0237] [7] In any of the electric vacuum cleaners described in any of [1] to [5],

[0238] Information indicating the state of the secondary battery includes information indicating the temperature state of the secondary battery.

[0239] The control unit determines the magnitude of the control element based on information indicating the degradation state of the secondary battery and information indicating the temperature state of the secondary battery.

[0240] [8] In any of the electric vacuum cleaners described in any of [1] to [6],

[0241] Information indicating the state of the secondary battery includes information indicating the internal resistance of the secondary battery.

[0242] The control unit determines the magnitude of the control element based on information representing the internal resistance of the secondary battery.

[0243] [9] In the electric vacuum cleaner as described in [7],

[0244] Information indicating the state of the secondary battery includes information indicating the temperature state of the secondary battery.

[0245] The control unit determines the magnitude of the control element based on information representing the internal resistance of the secondary battery and information representing the temperature state of the secondary battery.

[0246]

[10] In any of the electric vacuum cleaners described in [1] to [8],

[0247] Information indicating the state of the secondary battery includes information indicating the remaining capacity of the secondary battery.

[0248] The control unit determines the size of the control element based on information representing the internal resistance of the secondary battery and information representing the remaining capacity of the secondary battery.

[0249]

[11] In any of the electric vacuum cleaners described in any of [1] to [9],

[0250] Information indicating the state of the secondary battery includes information indicating the temperature state of the secondary battery.

[0251] The control unit determines the magnitude of the control element based on information indicating the temperature state of the secondary battery.

[0252]

[12] An electric vacuum cleaner as described in any one of [1] to

[10]

[0253] The electric vacuum cleaner also includes a storage unit that stores information indicating the state of the secondary battery.

[0254] When the control unit detects an improvement in the deterioration state of the secondary battery, it initializes at least a portion of the information stored in the storage unit.

[0255]

[13] An electric vacuum cleaner, comprising:

[0256] Electric motor;

[0257] A secondary battery supplies power to the electric motor; and

[0258] The control unit determines the magnitude of the current supplied from the secondary battery to the motor during the current use of the electric vacuum cleaner based on at least one of information indicating the state of the secondary battery detected during charging and information indicating the state of the secondary battery detected during the last use of the electric vacuum cleaner.

Claims

1. An electric vacuum cleaner, comprising: Electric motor; A secondary battery supplies power to the electric motor; and The control unit, based on information indicating the state of the secondary battery, determines the magnitude of control elements related to the power supplied from the secondary battery to the motor. The information indicating the state of the secondary battery includes information indicating the degradation state of the secondary battery. The control unit detects the degradation state of the secondary battery based on the rate of change of the secondary battery's voltage during charging, and determines the magnitude of the control element for use of the electric vacuum cleaner after charging based on information indicating the detected degradation state of the secondary battery, and energizes the motor in a phase determined based on the detection result of the motor's rotor position. The control unit determines the control elements as the energizing time, lead angle, freewheeling time, freewheeling angle, duty cycle related to the energizing period of the motor windings relative to the repetition period, or the modulation frequency of the pulse signal used to control the energizing, and determines the magnitude of the determined control elements.

2. The electric vacuum cleaner as described in claim 1, The control unit determines the magnitude of the control element for the current use of the electric vacuum cleaner based on information indicating the state of the secondary battery detected during the last use of the electric vacuum cleaner.

3. The electric vacuum cleaner as described in claim 1, The control unit can drive the motor in a first operating mode and a second operating mode with a higher speed than the first operating mode. When switching from the first operating mode to the second operating mode, it determines the magnitude of the control element in the second operating mode based on information indicating the state of the secondary battery detected in the first operating mode.

4. The electric vacuum cleaner as described in claim 1, Information indicating the state of the secondary battery includes information indicating the temperature state of the secondary battery. The control unit determines the magnitude of the control element based on information indicating the degradation state of the secondary battery and information indicating the temperature state of the secondary battery.

5. The electric vacuum cleaner as described in claim 1, The electric vacuum cleaner also includes a storage unit that stores information indicating the state of the secondary battery. When the control unit detects an improvement in the deterioration state of the secondary battery, it initializes at least a portion of the information stored in the storage unit.

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