JP7499066B2 - Vacuum cleaner - Google Patents

Description

The present invention relates to a vacuum cleaner.

A typical vacuum cleaner has operating modes such as a high suction mode, a low suction mode, and an automatic switching mode (see, for example, Patent Document 1). A user switches between these operating modes using a switch when cleaning. For example, if a user wants to clean as quietly as possible, the user selects the low suction mode. For example, if a user wants to vacuum up dirt powerfully, the user selects the high suction mode. For example, if a user wants to clean while reducing power consumption, the user selects the automatic switching mode.

JP 2012-152303 A

However, conventional vacuum cleaners do not change the power supplied to the motor that rotates the rotating brush or the motor of the electric blower even when the type of surface to be cleaned changes while operating in high suction power mode, which can result in more power being consumed than necessary.
The present invention has been made in consideration of the above circumstances, and provides a vacuum cleaner capable of reducing power consumption.

The present invention provides a vacuum cleaner comprising an electric blower having a fan arranged to draw air into the vacuum cleaner and a first motor to rotate the fan, a rotating brush, a second motor arranged to rotate the rotating brush, and a control unit arranged to control the vacuum cleaner in switchable operation modes, the control unit arranged to determine the type of surface to be cleaned, the type of surface to be cleaned including a first surface to be cleaned and a second surface to be cleaned in which the load on the rotation of the second motor is greater than that of the first surface to be cleaned, the operation modes including a high suction mode and a low suction mode in which the power supplied to the first motor is less than that of the high suction mode, and the control unit arranged to control the vacuum cleaner with a set value of a control parameter such that the rotation speed of the second motor when cleaning the first surface to be cleaned in the high suction mode is smaller than the rotation speed of the second motor when cleaning the second surface to be cleaned in the high suction mode.

The vacuum cleaner of the present invention can reduce power consumption.

1 is a schematic perspective view of a vacuum cleaner according to an embodiment of the present invention; 1 is a block diagram showing an electrical configuration of a vacuum cleaner according to an embodiment of the present invention;

The vacuum cleaner of the present invention comprises an electric blower having a fan arranged to draw air into the vacuum cleaner and a first motor to rotate the fan, a rotating brush, a second motor arranged to rotate the rotating brush, and a control unit arranged to control the vacuum cleaner in switchable operation modes, the control unit arranged to determine the type of surface to be cleaned, the type of surface to be cleaned including a first surface to be cleaned and a second surface to be cleaned in which the load on the rotation of the second motor is greater than that of the first surface to be cleaned, the operation modes including a high suction mode and a low suction mode in which the power supplied to the first motor is less than that of the high suction mode, and the control unit arranged to control the vacuum cleaner with a set value of a control parameter such that the rotation speed of the second motor when cleaning the first surface to be cleaned in the high suction mode is smaller than the rotation speed of the second motor when cleaning the second surface to be cleaned in the high suction mode.

It is preferable that the control unit is configured to control the vacuum cleaner without changing the set values of the control parameters for adjusting the power supplied to the first motor and the second motor even if the type of surface to be cleaned changes when the vacuum cleaner is controlled in the low suction mode. By controlling the vacuum cleaner in such a low suction mode, cleaning can be performed quietly regardless of the type of surface to be cleaned, and the usability of the vacuum cleaner can be improved in situations where quietness is preferable, such as when cleaning at night.
The operation modes preferably include an automatic switching mode in which a set value of a control parameter for adjusting the power supplied to the first motor and the second motor is changed according to the type of surface to be cleaned. The control unit is preferably configured to control the vacuum cleaner with a set value of a control parameter such that, when the first surface to be cleaned is being cleaned in the automatic switching mode, both the rotation speed of the first motor and the rotation speed of the second motor are smaller than when the second surface to be cleaned is being cleaned in the automatic switching mode. This can improve the dirt removal efficiency of the vacuum cleaner.

The vacuum cleaner preferably includes a dust detection sensor arranged to detect the amount of dust sucked by the vacuum cleaner. The control unit is also preferably arranged to control the vacuum cleaner without changing the set values of the control parameters for adjusting the power supplied to the first motor and the second motor, even if an increase in the amount of dust sucked is detected based on the sensor output of the dust detection sensor when the vacuum cleaner is controlled in low suction mode. By controlling the vacuum cleaner in such a low suction mode, cleaning can be performed quietly regardless of whether an increase in dust is detected, and the usability of the vacuum cleaner can be improved in situations where quietness is preferable, such as when cleaning at night.

The present invention will be described in more detail below with reference to several embodiments. The configurations shown in the drawings and the following description are merely examples, and the scope of the present invention is not limited to those shown in the drawings and the following description.

First Embodiment FIG. 1 is a schematic cross-sectional view of a vacuum cleaner according to this embodiment, and FIG. 2 is a block diagram showing the electrical configuration of the vacuum cleaner.
The electric vacuum cleaner 50 of this embodiment comprises an electric blower 4 having a fan 2 arranged to suck air into the vacuum cleaner 50 and a first motor 3 to rotate the fan 2, a rotating brush 17, a second motor 18 arranged to rotate the rotating brush 17, and a control unit 8 arranged to control the electric vacuum cleaner 50 in switchable operating modes, the control unit 8 being arranged to determine the type of surface to be cleaned, the types of surface to be cleaned including a first surface to be cleaned and a second surface to be cleaned in which the load on the rotation of the second motor 17 is greater than that on the first surface to be cleaned, the operating modes including a high suction power mode and a low suction power mode in which the power supplied to the first motor 3 is less than that in the high suction power mode, and the control unit 8 being arranged to control the vacuum cleaner 50 with set values of control parameters such that the rotation speed of the second motor 18 when the first surface to be cleaned is cleaned in the high suction power mode is smaller than the rotation speed of the second motor 18 when the second surface to be cleaned is cleaned in the high suction power mode.

The vacuum cleaner 50 of this embodiment may be a stick type, a canister type, a handheld type, or a self-propelled vacuum cleaner (robot vacuum cleaner). The dust collection method of the vacuum cleaner 50 may be a paper bag type, a cyclone type, or a filter type. The vacuum cleaner 50 may be a cordless vacuum cleaner that uses a battery 13 as a driving power source, or a corded vacuum cleaner that connects to an outlet by an electric cord. The vacuum cleaner 50 illustrated in FIG. 1 is a stick type cordless vacuum cleaner that uses a cyclone dust collection method and a battery as a driving power source.

The electric blower 4 is a member that draws in and exhausts air, and includes a fan 2 and a first motor 3 that rotates the fan 2. The electric blower 4 can be placed downstream of the air flow of the dust collection section 11. A control board including an electric blower drive circuit and the like may be attached to the electric blower 4. The first motor 3 may be a motor with carbon brushes, or may be a brushless motor.

In the vacuum cleaner 50, as the fan 2 of the electric blower 4 rotates, outside air is sucked into the vacuum cleaner 50 together with dust from the suction port 5, thereby cleaning surfaces such as floors, tatami mats, and carpets. The air sucked into the vacuum cleaner 50 from the suction port 5 flows through an air flow path and into the dust collection section 11, and the dust sucked in together with the air is collected inside the dust collection section 11, and the dust in the air is removed. The air that has passed through the dust collection section 11 is discharged from the exhaust port.
The suction power of the vacuum cleaner 50 can be controlled by adjusting the power or current supplied from the power supply unit 12 to the first motor 3 of the electric blower 4 by the first adjustment unit 37 of the control unit 8, thereby adjusting the rotation speed of the fan 2.
In addition, the rotation speed of the rotating brush 17 can be controlled by adjusting the power or current supplied from the power supply unit 12 to the second motor 18 by the second adjustment unit 38 of the control unit 8 .

When the vacuum cleaner 50 uses a paper bag for dust collection, the dust collection unit 11 is a paper bag. When the vacuum cleaner 50 uses a cyclone for dust collection, the dust collection unit 11 is a cyclone dust collector. When the vacuum cleaner 50 uses a filter for dust collection, the dust collection unit 11 can have a filter and a dust cup.

The power supply unit 12 may be a DC power supply unit or an AC power supply unit. The power supply unit 12 is connected to the control unit 8 by a power line and can supply power to the first motor 3 of the electric blower 4 and the like via the control unit 8.
When the power supply unit 12 is a DC power supply unit, the power supply unit 12 may include a battery 13, and DC power may be supplied from the battery 13 to the first motor 3 of the electric blower 4, etc. The type of battery 13 is not particularly limited as long as it is a secondary battery that can be charged and discharged, and may be, for example, a lithium ion battery, a nickel metal hydride battery, a nickel cadmium battery, etc. In addition, the control unit 8 may include a power supply circuit 14 provided to control the charging and discharging of the battery 13.

When the power supply unit 12 is an AC power supply unit, the power supply unit 12 can be a power supply unit that uses AC current supplied from an outlet via a power cord. AC power from this AC power supply unit or DC power converted by an AC-DC converter can be supplied to the first motor 3 of the electric blower 4, etc.

The suction port body 16 is a part having the suction port 5, and is provided so that dust on the surface to be cleaned can be sucked from the suction port 5. The suction port body 16 can be a suction port body for cleaning floors and carpets.
The suction port body 16 has a rotating brush 17. The rotating brush 17 is a brush that rotates when the suction port body 16 is moved to clean the surface to be cleaned. The rotating rotating brush 17 can scrape out dust from the surface to be cleaned, and the scraped out dust can be sucked in from the suction port 5. This makes it possible to thoroughly remove dust from the surface to be cleaned. The rotating brush 17 is a power brush that is rotated by the second motor 18.

The operation unit 10 is a portion with which an operator operates the vacuum cleaner 50. The operation unit 10 can include a hand grip 6 and a switch unit 9.
The hand grip 6 is a part that an operator holds with his/her hand in order to move the suction port body 16. The hand grip 6 has a shape that allows the operator to easily hold it with his/her hand.

The switch unit 9 is a part provided so that an operator can perform operations such as turning the vacuum cleaner 50 on and off and switching the operation mode. The switch unit 9 can be connected to the control unit 8 by a signal line or the like. When the operator presses a button on the switch unit 9, the control unit 8 detects that the button has been pressed and controls the vacuum cleaner 50.
The switch unit 9 may include, for example, operation mode switching buttons such as a strong operation button, a weak operation button, and an automatic operation button, and an off button. The vacuum cleaner 50 may have operation modes such as a low suction mode, a high suction mode, and an automatic switching mode, and the switch unit 9 includes operation mode switching buttons such as a weak operation button for operating in a low suction mode, a strong operation button for operating in a high suction mode, and an automatic operation button for operating in an automatic switching mode, and an off button. When the vacuum cleaner 50 is stopped, the operator presses the operation mode switching button, and the vacuum cleaner 50 starts operating according to the mode of the pressed button. Note that if a button for another mode is pressed while operating in a certain mode, the vacuum cleaner 50 continues operating in the newly pressed mode. The operation is stopped by pressing the off button. The switch unit 9 may also be a part that operates the vacuum cleaner 50 using an external device such as a smartphone. When the operation modes include, for example, a low suction mode, an automatic switching mode, and a high suction mode, the operator can use the switch unit 9 to switch to any one of these operation modes.
The switch unit 9 can be disposed at a position where an operator can press the button of the switch unit 9 with his/her thumb while holding the hand grip 6 .

The control unit 8 is a part that controls the vacuum cleaner 50, and has, for example, a calculation unit, a memory unit 36, a first adjustment unit 37, a second adjustment unit 38, etc. The control unit 8 can have a control module 19. The control module 19 is, for example, a microcontroller having a calculation unit, a memory unit 36, a timer, an input/output port, etc. The calculation unit is, for example, a CPU, a GPU, an FPGA, etc. The memory unit 36 can include ROMs such as mask ROM, EPROM, EEPROM, and flash memory (non-volatile memory), and RAMs such as FeRAM, SRAM, and DRAM.
The control unit 8 may be composed of a plurality of control boards. These plurality of control boards can be connected by signal lines or power lines. The control unit 8 is composed of, for example, a control board having a drive circuit for the electric blower, a control board having a drive circuit for the rotary brush, a control board having a power supply circuit 14, a microcontroller, and the like. These circuits, etc. may be mounted on the same control board.

Control software for controlling the vacuum cleaner 50 is installed in the memory unit 36 of the control unit 8. The control software may include a control system. The control software may also include firmware for controlling the electric blower 4, the second motor 18, the power supply circuit 14, the first adjustment unit 37, the second adjustment unit 38, the switch unit 9, and the like. The firmware may also be considered as part of the electric blower 4, the second motor 18, the power supply circuit 14, the first adjustment unit 37, the second adjustment unit 38, the switch unit 9, and the like. The control software may include control parameters for adjusting the power or power supplied to the first motor 3 using the first adjustment unit 37 and control parameters for adjusting the power or power supplied to the second motor 18 using the second adjustment unit 38. The memory unit 36 stores the setting values of these control parameters for each operation mode.

The control unit 8 may have a first adjustment unit 37 provided to adjust the power or current supplied from the power supply unit 12 to the first motor 3 of the electric blower 4. The suction power of the vacuum cleaner 50 may be adjusted (controlled) using this first adjustment unit 37.
The first adjustment unit 37 is, for example, a part of a drive circuit for an electric blower. The first adjustment unit 37 can include a PWM circuit having a transistor. By adjusting the cycle or duty ratio of repeatedly turning on and off this transistor, it is possible to adjust the power supplied from the power supply unit 12 to the first motor 3. The first adjustment unit 37 can be provided so as to stop the supply of power from the power supply unit 12 to the first motor 3. The first adjustment unit 37 may also include a phase control circuit having a bidirectional thyristor.

During stable operation, for example, the first adjustment unit 37 can adjust (control) the power or current supplied to the first motor 3 by setting a set value stored in the memory unit 36 as a control parameter. The control parameter can be, for example, the rotation speed of the first motor 3, the power value supplied to the first motor 3, or the current value flowing through the first motor 3. The set value of this control parameter can be set for each operation mode and is stored in the memory unit 36. Furthermore, the first adjustment unit 37 can perform feedback control based on a measured value corresponding to the control parameter.

The control unit 8 may have a second adjustment unit 38 provided to adjust the power or current supplied from the power supply unit 12 to the second motor 18 that rotates the rotating brush 17. The rotation speed of the rotating brush 17 may be adjusted using the second adjustment unit 38.
The second adjustment unit 38 can include a PWM circuit having a transistor. By adjusting the cycle or duty ratio of repeatedly turning on and off this transistor, it is possible to adjust the power supplied from the power supply unit 12 to the second motor 18. The second adjustment unit 38 can also be provided to stop the supply of power from the power supply unit 12 to the second motor 18.
The second adjustment unit 38 may also include a phase control circuit having a bidirectional thyristor.
The second adjustment unit 38 can adjust the power or current supplied to the second motor 18, for example, so that the rotation speed of the second motor 18 is substantially constant during stable operation.

For example, during stable operation, the second adjustment unit 38 can adjust the power or current supplied to the second motor 18 by setting a set value stored in the storage unit 36 as a control parameter. The control parameter can be, for example, the rotation speed of the second motor 18, the value of power supplied to the second motor 18, or the value of current flowing through the second motor 18. The set value of this control parameter can be set for each operation mode and is stored in the storage unit 36.
In addition, the second adjustment unit 38 can perform feedback control based on a measured value corresponding to the control parameter.

The control unit 8 is configured to determine the type of surface to be cleaned based on the amount of current, voltage or power flowing through the second motor 18 .
The rotating brush 17 driven by the second motor 18 scrapes off dust from the surface to be cleaned while rotating, so frictional resistance occurs between the rotating rotating brush 17 and the surface to be cleaned. The magnitude of this frictional resistance varies depending on the type of surface to be cleaned. For example, when the surface to be cleaned is flooring or tatami (first surface to be cleaned), the surface to be cleaned has few irregularities, so the frictional resistance is small. Therefore, the load on the second motor 18 is also small. For example, when the surface to be cleaned is a carpet (second surface to be cleaned), the surface to be cleaned has many irregularities, so the frictional resistance is large. Therefore, the load on the second motor 18 is also large.

When the control parameter for the power supplied to the second motor 18 is the rotation speed of the second motor 18, the second adjustment unit 38 adjusts the power supply so that the rotation speed of the second motor 18 is constant at the set value (rotation speed) of the control parameter. When cleaning of the surface to be cleaned is proceeded under such control, if the surface to be cleaned changes from flooring or tatami (first surface to be cleaned) to carpet (second surface to be cleaned), the load on the second motor 18 increases and the amount of current flowing to the second motor 18 increases. This amount of current can be detected by a current sensor. Also, if the surface to be cleaned changes from carpet (second surface to be cleaned) to flooring or tatami (first surface to be cleaned), the load on the second motor 18 decreases and the amount of current flowing to the second motor 18 decreases. Therefore, the control unit 8 can determine whether the surface to be cleaned is flooring or tatami (first surface to be cleaned) or carpet (second surface to be cleaned) based on the amount of current flowing to the second motor 18.

For example, a threshold value (amount of current) for determining the type of surface to be cleaned can be stored in the memory unit 36. Then, the control unit 8 can determine that the surface to be cleaned is a flooring or tatami mat (first surface to be cleaned) when the amount of current flowing through the second motor 18 is smaller than the threshold value, and can determine that the surface to be cleaned is a carpet (second surface to be cleaned) when the amount of current flowing through the second motor 18 is larger than the threshold value. Then, the control unit 8 can change the setting value of the control parameter based on the determination result of the type of surface to be cleaned, and change the suction power of the vacuum cleaner 50 (the power of the first motor 3) or the rotation speed of the rotating brush 17 (the power of the second motor 18).
Here, an example is described in which the surface to be cleaned is determined based on the amount of current, but the surface to be cleaned can also be determined based on the power supplied to the second motor 18 or the voltage applied to the second motor 18. Furthermore, the control unit 8 may determine the type of the surface to be cleaned based on an image or video captured by a camera or the like that is provided to capture an image of the surface to be cleaned.

The control unit 8 is configured to control the vacuum cleaner 50 in switchable operation modes. An operation mode is an operation method of the vacuum cleaner 50, and the user can switch the operation mode to operate the vacuum cleaner 50 based on the cleaning target, time of day, power consumption, etc. The operation modes of the vacuum cleaner 50 can include a high suction mode, a low suction mode, and an automatic switching mode. Table 1 shows examples of the power of the first motor 3 (the suction power of the vacuum cleaner 50) and the power of the second motor 18 (the rotation speed of the rotating brush 17) in the high suction mode, the low suction mode, and the automatic switching mode.

In this example, the control unit 8 is provided so that the power of the first motor 3 (the suction power of the vacuum cleaner 50) can be switched between three levels: high, medium, and low. In this case, the storage unit 36 stores the set values of the control parameters corresponding to the high, medium, and low powers of the first motor 3. The control unit 8 is also provided so that the power of the second motor 18 (the number of rotations of the rotating brush 17) can be switched between three levels: high, medium, and low. In this case, the storage unit 36 stores the set values of the control parameters corresponding to the high, medium, and low powers of the second motor 18.
Here, an example is shown in which the control unit 8 switches the power of the first motor 3 and the power of the second motor 18 in three stages, but the control unit 8 may be configured to be able to adjust the power of the first motor 3 or the power of the second motor 18 more finely.

When the operator switches (selects) the operating mode using the switch unit 9, the control unit 8 reads the setting value stored in the memory unit 36 and sets the control parameters to this setting value, thereby changing the power of the first motor 3 (the suction power of the vacuum cleaner 50) and the power of the second motor 18 (the rotation speed of the rotating brush 17). In addition, when the control unit 8 detects that the type of surface to be cleaned has changed, it reads the setting value stored in the memory unit 36 and sets the control parameters to this setting value, thereby changing the power of the first motor 3 (the suction power of the vacuum cleaner 50) and the power of the second motor 18 (the rotation speed of the rotating brush 17).

For example, when the operator presses the switch unit 9 to start cleaning flooring or tatami mats (first surface to be cleaned) in high suction mode (or when switching from low suction mode or automatic switching mode to high suction mode), the control unit 8 sets the control parameter to a setting value corresponding to the power "high" of the first motor 3 and supplies power to the first motor 3 by the first adjustment unit 37. This allows the operator to clean with high suction. The control unit 8 also sets the control parameter to a setting value corresponding to the power "medium" of the second motor 18 and supplies power to the second motor 18 by the second adjustment unit 38. As a result, the rotating brush 17 rotates at a "medium" rotation speed. Because flooring or tatami mats (first surface to be cleaned) have few irregularities, it is possible to sufficiently remove dust from the first surface to be cleaned even if the rotation speed of the rotating brush 17 is "medium". In addition, by setting the rotation speed of the rotating brush 17 to "medium", the impact of the rotating brush 17 on the first surface to be cleaned can be reduced, and damage to the first surface to be cleaned can be suppressed. Furthermore, the power consumption of the second motor 18 can be reduced, slowing down the rate at which the remaining charge of the battery 13 decreases.

After that, when the control unit 8 detects that the surface to be cleaned has changed from the first surface to the second surface to be cleaned (carpet), the control unit 8 uses the set value corresponding to the power "high" of the first motor 3 as a control parameter and supplies power to the first motor 3 through the first adjustment unit 37. In other words, even if the surface to be cleaned has changed, the set value of this control parameter does not change. Also, when the control unit 8 detects that the surface to be cleaned has changed from the first surface to the second surface to be cleaned (carpet), the control unit 8 sets the set value corresponding to the power "high" of the second motor 18 as the control parameter and supplies power to the second motor 18 through the second adjustment unit 38. In other words, the rotation speed of the rotating brush 17 is increased from "medium" to "high". By increasing the rotation speed of the rotating brush 17, dust that has entered the carpet can be thoroughly scraped out by the rotating brush 17, and dust on the second surface to be cleaned can be thoroughly removed.

In this way, by providing the control unit 8 to control the vacuum cleaner 50 with a set value of the control parameter such that the rotation speed of the second motor 18 when cleaning the first cleaned surface in the high suction power mode is smaller than the rotation speed of the second motor 18 when cleaning the second cleaned surface in the high suction power mode, the first cleaned surface and the second cleaned surface can be thoroughly cleaned, damage to the first cleaned surface can be prevented, and power consumption of the second motor 18 can be reduced.
When the surface to be cleaned is changed from the second surface to the first surface to be cleaned, the control method is reversed.

When the operator uses the switch unit 9 to switch from the high suction mode or the automatic switching mode to the low suction mode to clean flooring or tatami (first surface to be cleaned) (or to start cleaning in the low suction mode), the control unit 8 sets the control parameter to a setting value corresponding to the "low" power of the first motor 3 and supplies power to the first motor 3 by the first adjustment unit 37. The control unit 8 also sets the control parameter to a setting value corresponding to the "low" power of the second motor 18 and supplies power to the second motor 18 by the second adjustment unit 38. This makes it possible to clean the first surface to be cleaned while suppressing the operating noise of the vacuum cleaner 50 (maintaining quietness).

Thereafter, even if the control unit 8 detects that the surface to be cleaned has changed from the first surface to the second surface to be cleaned (carpet), the control unit 8 supplies power to the first motor 3 and the second motor 18 without changing the set values of the control parameters for adjusting the power supplied to the first motor 3 and the second motor 18. This allows the vacuum cleaner 50 to clean the second surface to be cleaned while suppressing the operating noise (maintaining quietness). In other words, in the low suction power mode, cleaning can be performed quietly regardless of the type of surface to be cleaned. As a result, the usability of the vacuum cleaner 50 can be improved in situations where quietness is preferable, such as when cleaning at night.
The same applies when the surface to be cleaned is changed from the second surface to be cleaned to the first surface to be cleaned.

When the operator uses the switch unit 9 to switch from the low suction mode or high suction mode to the automatic switching mode to clean flooring or tatami (first surface to be cleaned) (or when starting cleaning in the automatic switching mode), the control unit 8 sets the control parameter to a setting value corresponding to the "medium" power of the first motor 3 and supplies power to the first motor 3 by the first adjustment unit 37. The control unit 8 also sets the control parameter to a setting value corresponding to the "medium" power of the second motor 18 and supplies power to the second motor 18 by the second adjustment unit 38. By setting both the power of the first motor 3 and the power of the second motor 18 to "medium", it is possible to suppress the power consumption of the first motor 3 and the second motor 18, and to slow down the rate at which the remaining charge of the battery 13 decreases.

After that, when the control unit 8 detects that the surface to be cleaned has changed from the first surface to be cleaned to the second surface to be cleaned (carpet), the control unit 8 sets the control parameter to a setting value corresponding to the "high" power of the first motor 3 and supplies power to the first motor 3 via the first adjustment unit 37, and sets the control parameter to a setting value corresponding to the "high" power of the second motor 18 and supplies power to the second motor 18 via the second adjustment unit 38. This makes it possible to increase both the suction power of the vacuum cleaner 50 and the rotation speed of the rotating brush 17, and to thoroughly remove dust from the second surface to be cleaned.

Second Embodiment A vacuum cleaner 50 according to a second embodiment includes a dust detection sensor 20 .
The dust detection sensor 20 is a sensor provided to detect dust passing through the air flow path through which the air sucked in from the suction port 5 flows. The dust detection sensor 20 is controlled by the control unit 8. The dust detection sensor 20 may have, for example, a light-emitting unit and a photoelectric conversion unit. The light-emitting unit and the photoelectric conversion unit are arranged to face each other across the air flow path through which the air and dust sucked into the vacuum cleaner 50 pass, and the photoelectric conversion unit is provided so as to receive light emitted by the light-emitting unit. The light emitted by the light-emitting unit may be infrared light.
When dust flows through the airflow path together with the air, the dust blocks the light or infrared rays irradiated from the light emitting unit to the photoelectric conversion unit. Therefore, the output (sensor output) of the photoelectric conversion unit changes depending on the amount of dust flowing through the airflow path. Therefore, the control unit 8 can detect the amount of dust sucked in by the vacuum cleaner 50 using the dust detection sensor 20.

The control unit 8 can be configured to detect an increase in the amount of dust sucked into the vacuum cleaner 50 based on the sensor output of the dust detection sensor 20. For example, when the sensor output of the dust detection sensor 20 becomes larger than a threshold value or when the sensor output becomes smaller than a threshold value, the control unit 8 determines that the amount of dust has increased and detects an increase in dust.

The control unit 8 can also change the set values of the control parameters based on whether an increase in dust is detected using the dust detection sensor 20, and change the suction power of the vacuum cleaner 50 (the power of the first motor 3) or the rotation speed of the rotating brush 17 (the power of the second motor 18).

For the vacuum cleaner 50 of the second embodiment, the power of the first motor 3 (the suction power of the vacuum cleaner 50) and the power of the second motor 18 (the rotation speed of the rotating brush 17) in the low suction power mode, the automatic switching mode, and the high suction power mode are shown in Table 2.

When the control unit 8 does not detect an increase in dust, the power of the first motor 3 and the power of the second motor 18 are the same as those in the first embodiment.
In the high suction power mode or automatic switching mode, when the control unit 8 is controlling the vacuum cleaner 50 with the power of the first motor 3 at "medium" or the power of the second motor 18 at "medium," if an increase in dust is detected based on the sensor output of the dust detection sensor 20, the control unit 8 changes the set value of the control parameter and switches the power of the first motor 3 or the power of the second motor 18 from "medium" to "high." This makes it possible to increase the suction power of the vacuum cleaner 50 or the rotation speed of the rotating brush 17 when the amount of dust increases, thereby improving the dust removal efficiency of the vacuum cleaner 50.

In the low suction mode, when the control unit 8 controls the vacuum cleaner 50 with the power of the first motor 3 set to "low" and the power of the second motor 18 set to "low," even if an increase in dust is detected based on the sensor output of the dust detection sensor 20, the control unit 8 supplies power to the first motor 3 and the second motor 18 without changing the set value of the control parameter for adjusting the power supplied to the first motor 3 and the second motor 18. This allows the vacuum cleaner 50 to clean the surface to be cleaned while suppressing the operating noise. In other words, in the low suction mode, cleaning can be performed quietly regardless of whether an increase in dust is detected. As a result, the usability of the vacuum cleaner 50 can be improved in situations where quietness is preferable, such as when cleaning at night.
Other configurations are similar to those of the first embodiment. Furthermore, the description of the first embodiment also applies to the second embodiment unless there is a contradiction.

2: Fan 3: First motor 4: Electric blower 5: Suction port 6: Hand grip 8: Control unit 9: Switch unit 10: Operation unit 11: Dust collection unit 12: Power supply unit 13: Battery 14: Power supply circuit 16: Suction port body 17: Rotating brush 18: Second motor 19: Control module 20: Dust detection sensor 25: Extension tube 36: Memory unit 37: First adjustment unit 38: Second adjustment unit 50: Vacuum cleaner

Claims (3)

The vacuum cleaner includes an electric blower having a fan arranged to draw air into the vacuum cleaner and a first motor for rotating the fan, a rotating brush, a second motor arranged to rotate the rotating brush, and a control unit arranged to control the vacuum cleaner in switchable operating modes,
The control unit is configured to determine a type of surface to be cleaned;
The types of the surfaces to be cleaned include a first surface to be cleaned and a second surface to be cleaned that imposes a larger load on the rotation of the second motor than on the first surface to be cleaned,
the operation modes include a high suction force mode and a low suction force mode in which power supplied to the first motor and the second motor is smaller than that in the high suction force mode;
the control unit is configured to supply power to the first and second motors and, when detecting that the surface to be cleaned has changed from the first surface to the second surface to be cleaned while the first surface to be cleaned is being cleaned in the high suction power mode, control the vacuum cleaner with a set value of a control parameter such that the rotation speed of the second motor is made higher than the rotation speed of the second motor when the first surface to be cleaned is being cleaned in the high suction power mode;
the control unit is configured to control the vacuum cleaner without changing the set values of control parameters for adjusting the power supplied to the first motor and the second motor even if it detects that the type of the surface to be cleaned has changed from the first surface to the second surface when controlling the vacuum cleaner in the low suction power mode while supplying power to the first and second motors. The operation mode includes an automatic switching mode in which a set value of a control parameter for adjusting power supplied to the first motor and the second motor is changed according to the type of the surface to be cleaned,
2. The vacuum cleaner according to claim 1, wherein the control unit is configured to control the vacuum cleaner with set values of control parameters such that, when a first cleaning surface is being cleaned in the automatic switching mode, both the rotation speed of the first motor and the rotation speed of the second motor are smaller than when a second cleaning surface is being cleaned in the automatic switching mode. a dust detection sensor arranged to detect an amount of dust sucked by the vacuum cleaner;
3. The vacuum cleaner according to claim 1 or 2, wherein the control unit is configured to control the vacuum cleaner without changing the set values of control parameters for adjusting the power supplied to the first motor and the second motor even when an increase in dust to be sucked in is detected based on the sensor output of the dust detection sensor when the vacuum cleaner is controlled in the low suction power mode.