Vacuum cleaner

Abstract

To provide a vacuum cleaner capable of properly controlling a motor according to the temperature condition of the motor.SOLUTION: The vacuum cleaner includes an electric blower, a motor 12 for driving a cleaning body, and a control means 13 for controlling the operation of the motor 12. The control means 13 controls the driving power of the motor 12 on the condition that the result of comparison between the current value of the motor 12 or its related value and a predetermined threshold value is the same for a predetermined determination time or longer, and when it is determined that the cooling effect on the motor 12 is high, the control means 13 makes at least one of the reduction correction of the current value of the motor 12 used for the comparison, the increase correction of the threshold value, and the increase correction of the determination time stricter to execute the protection control of the motor 12.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a vacuum cleaner including a motor for cleaning a part to be cleaned. [Background technology]

[0002] Conventionally, electric vacuum cleaners have used suction inlets with a so-called active brush structure, in which a rotating cleaning body is rotated by a motor. In such suction inlets, the rotating cleaning body rotated by the power of the motor first picks up dust from the surface to be cleaned and then sucks it up, thereby efficiently removing dust from surfaces to be cleaned, such as carpets, where dust tends to become entangled.

[0003] In consideration of safety and energy saving, it is preferable that the rotation of the rotating cleaning element be suppressed or stopped when the rotating cleaning element of the suction port element is away from the surface to be cleaned. On the other hand, in situations where dust removal performance by the suction port element is required, such as on a carpet, it is preferable that the rotating cleaning element rotates with sufficient torque. Therefore, there is known a device that reduces the driving power of the motor when a comparison value based on the motor's current consumption continues to be below a predetermined threshold value for a predetermined time while the motor is running, and increases the driving power of the motor to increase the rotational torque when it is determined that the comparison value exceeds the predetermined threshold value, such as when the suction port element is on a carpet.

[0004] Furthermore, when the suction nozzle is placed on a long-pile carpet or when a cloth or other material gets caught in the rotating cleaning body, the motor may lock and a very large current may flow, which could result in the risk of element damage.Therefore, some vacuum cleaners constantly monitor the current consumption of the motor, and when it is determined that the current consumption exceeds a predetermined threshold for a predetermined period of time, it is determined that the motor rotation has locked and the motor operation is stopped.

[0005] Motors tend to consume more current per load in low-temperature environments and less current per load in high-temperature environments. In the case of a configuration in which motor behavior is controlled based on current fluctuations, if the threshold value is fixed, it is expected that temperature conditions will affect the judgment for control. Therefore, in order to reliably make judgments even for fluctuations or differences in current values ​​due to temperature differences, which are closely related to the rotational load of the rotating cleaning element or motor, the above-mentioned control or judgment is suspended for a certain period of time at the beginning of startup when the motor is thought to be cold, or the judgment conditions for control are corrected for a certain period of time from the start of operation when the outside temperature is low when the motor is started.

[0006] However, even after a certain time has elapsed since the start of operation, the motor is cooled by the air drawn in by the electric blower during cleaning operation, and so it is desirable to be able to perform control appropriately. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2022-68680 [Patent Document 2] Japanese Patent Application Laid-Open No. 2024-77208 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a vacuum cleaner that can appropriately control a motor in accordance with the temperature condition of the motor. [Means for solving the problem]

[0009] The vacuum cleaner of the present embodiment includes an electric blower, a motor that drives a cleaning element, and a control means for controlling the operation of the motor. The control means controls the drive power of the motor when a comparison of the motor current value or a related value with a predetermined threshold value indicates that the result is the same for a predetermined determination time or longer. If it is determined that the cooling effect on the motor is high, the control means tightens the conditions for implementing protection control of the motor by relatively increasing at least one of the following: a reduction correction of the motor current value or the related value used for comparison, an increase correction of the threshold value, or an increase correction of the determination time. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a partial internal structure of an electric vacuum cleaner according to an embodiment; [Figure 2] FIG. 2 is a cross-sectional view schematically showing a cleaning tool of the electric vacuum cleaner. [Figure 3] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment will be described with reference to the drawings.

[0012] 1 and 2, reference numeral 1 denotes a cleaning tool. The cleaning tool 1 is also called a cleaning head or the like and cleans a cleaning target F, which is a surface to be cleaned such as a floor. The cleaning tool 1 includes a case body 10. A dust collection port 100 is formed in the case body 10. A cleaning body 11 is also arranged in the case body 10. In this embodiment, the cleaning body is, for example, a rotatable cleaning body. The cleaning body 11 is driven by a motor 12 to sweep up dust on the cleaning target F into the dust collection port 100. In this embodiment, the cleaning body 11 is attached to the dust collection port 100. The motor 12 is controlled by control means 13. In addition, the cleaning tool 1 has a connection pipe 14, which is a connection part, connected to the case body 10. The connection pipe 14 is in communication with the dust collection port 100.

[0013] As shown in FIG. 3 , the cleaning tool 1 is used in a vacuum cleaner CL. In this embodiment, the cleaning tool 1 is applied to a suction-type vacuum cleaner CL that sucks dust and air into a separation unit 4 by using negative pressure generated by driving an electric blower 3, which is a suction source disposed in a vacuum cleaner body 2 of the vacuum cleaner CL. The vacuum cleaner CL may be any type, such as a floor-traveling type, a canister type, a stick type, an upright type, a handheld type, or a self-propelled vacuum cleaner. In this embodiment, the vacuum cleaner CL will be described using a stick-type vacuum cleaner as an example. In the illustrated example, the cleaning tool 1, also referred to as a suction port body or floor brush, is mechanically and fluidly connected to the vacuum cleaner body 2 by a connecting pipe 14, either directly or indirectly via an extension pipe 5, which is a pipe portion. Through the connecting pipe 14, the suction side of the electric blower 3 communicates with the dust collection port 100 via the separation unit 4. Furthermore, the motor 12 (shown in FIG. 2 ) in the cleaning tool 1 is also located in an air passage that communicates with the suction side of the electric blower 3 separately from the dust collection port 100, and is cooled by the outside air drawn in by the operation of the electric blower 3. Alternatively, the motor 12 may be located in an air passage that passes through the dust collection port 100. Furthermore, in this embodiment, the operation of the electric blower 3, the suction power, or the operating intensity (i.e., operating mode, such as strong mode or weak mode), and the on / off of the cleaning element 11 or the motor 12 are set by the user by operating a switch 7 on the handheld control unit 6, which is a grip for gripping and operation. The vacuum cleaner body 2 is provided with a main body control unit 8 that operates the electric blower 3 in accordance with the operation set by the switch 7. The switch 7 or the main body control unit 8 is electrically connected to a control means 13. The control means 13 may be located in the cleaning tool 1, but in this embodiment, at least a part of the control means 13 is incorporated into the main body control unit 8. The power supply unit B of the electric vacuum cleaner CL is located, for example, in the vacuum cleaner body 2. In this embodiment, power supply unit B is a battery or a secondary battery, but is not limited to this and may be an AC-DC adapter that draws power from an external power source such as a commercial power source, a cord reel device, etc. Note that in this embodiment, power is supplied from power supply unit B to motor 12 and control means 13 (shown in FIG. 1) of cleaning tool 1, but is not limited to this and power supplies for motor 12 and control means 13 (shown in FIG. 1) may be provided separately within cleaning tool 1.

[0014] In the drawings, arrow FR indicates the forward direction, arrow RR indicates the backward direction, arrow U indicates the upward direction, arrow D indicates the downward direction, arrow L indicates the leftward direction, and arrow R indicates the rightward direction. These directions are based on the direction seen from the opposite side to the user when the vacuum cleaner CL is in use.

[0015] Next, the internal structure of the control means 13 will be described with reference to FIGS.

[0016] The control means 13 has a power variable unit 130 that varies the drive power of the motor 12. The power variable unit 130 may vary the drive power of the motor 12 continuously or may vary it in one of a plurality of steps. In this embodiment, the power variable unit 130 is capable of setting the drive power of the motor 12 to at least one of a plurality of steps.

[0017] The power variable unit 130 varies the drive power of the motor 12, for example, by adjusting the duration or amount of current flow from the power source to the motor 12, and sets the drive power of the motor 12 according to the duration of current flow to the motor 12. As an example, the power variable unit 130 sets the drive power of the motor 12 by using a PWM signal as the control signal, i.e., the applied voltage, to the motor 12 and adjusting the duty ratio of the PWM signal. That is, when the duty ratio of the PWM signal is set to 100%, the drive power of the motor 12 is maximized, and by lowering the duty ratio of the PWM signal, the drive power of the motor 12 is reduced, and the rotation speed and rotation torque of the cleaning element 11 are reduced. That is, when the power variable unit 130 increases the drive power of the motor 12, it increases the duty ratio, and when it decreases the drive power of the motor 12, it decreases the duty ratio. In this embodiment, the power variable unit 130 has a plurality of different duty ratios, and by selectively setting the duty ratio of the PWM signal of the motor 12 to one of these duty ratios, the drive power of the motor 12 can be set to a plurality of different drive powers.

[0018] The drive power setting of the motor 12 by the power variable unit 130 may be switched according to a user setting using the switch 7 (shown in FIG. 3 ), the strength of the suction power or the operating mode of the electric blower 3, or automatically according to the cleaning status. The cleaning status may refer to, for example, the type of floor constituting the area to be cleaned F or the amount of dust collected on the area to be cleaned F. That is, the power variable unit 130 may automatically select and set the drive power of the motor 12 in combination with a cleaning status detection unit, such as a type detection unit for detecting the type of area to be cleaned F and / or a dust amount detection unit for detecting the amount of dust collected. The type detection unit and the dust amount detection unit may have any known configuration. In this embodiment, for example, the power variable unit 130 sets the drive power of the motor 12 by selectively using one of a plurality of PWM signals with different duty ratios according to the desired control setting.

[0019] The control unit 13 also includes a current detection unit 131 that detects the current value of the motor 12. The current detection unit 131 detects the current value of the motor 12 at predetermined detection intervals. For example, the current detection unit 131 detects the current value of the motor 12 by passing a current through a low-resistance resistor (a detection element, i.e., a shunt resistor). The potential difference generated across the shunt resistor is amplified and input to an A / D converter (conversion unit), and the output of the A / D converter is captured. In this embodiment, the current value detected by the current detection unit 131 is, for example, a load current value. The load current value indicates the load state of the cleaning element 11 driven by the motor 12 and correlates with the actual current value of the motor 12. The actual current value of the motor 12 is, for example, the average of current values ​​acquired a predetermined number of times at predetermined intervals. This actual current value is highly dependent on the duty ratio of the PWM signal from the power variable unit 130. Therefore, in this embodiment, the load current value is calculated by dividing the actual current value by the duty ratio of the PWM signal in the power variable unit 130. That is, (load current value) = (actual current value) / (duty ratio). Therefore, the load current value in this embodiment is calculated based on the value of the current flowing through the motor 12 and the duty ratio.

[0020] In the control and judgment by the control means 13, a value related to the current value detected by the current detection unit 131 may be used instead of or in addition to the current value. The value related to the current value includes the current value itself flowing through the motor 12, a value calculated from the current value flowing through the motor 12 and correlated with this current value, such as a value obtained by subtracting a predetermined value from the current value flowing through the motor 12, and a value corrected by tightening and / or relaxing the conditions described below. Hereinafter, the "current value of the motor 12 or a value related thereto" will be simply referred to as the "current value of the motor 12," and the "rotational load of the cleaning element 11 or the motor 12" will be simply referred to as the "rotational load."

[0021] In the present embodiment, the current detection unit 131 has been described as including a current value acquisition unit that has a detection element, an A / D converter, etc. and acquires the value of a current flowing through the motor 12, an actual current value calculation unit that calculates an actual current value, and a load current value calculation unit that calculates a load current value, but the current value acquisition unit, actual current value calculation unit, and load current value calculation unit may each be configured as separate circuit units, or may be configured in any combination, or some of them may form part of other circuit units. In other words, the current detection unit 131 is not limited to being configured as an integrated unit that includes the current value acquisition unit, actual current value calculation unit, and load current value calculation unit.

[0022] Furthermore, the control means 13 has a storage unit 132 such as a memory. In this embodiment, the storage unit 132 stores the current value detected by the current detection unit 131, various judgment thresholds, judgment values, etc. The storage unit 132 also stores various data used for control by the control means 13, such as other arbitrary thresholds, flags, programs, etc.

[0023] The control means 13 also has a determination unit 133. The determination unit 133 determines the state of the cleaning tool 1, the motor 12, or the cleaning element 11 based on the current value detected by the current detection unit 131, and controls the setting of the drive power of the motor 12 by the power variable unit 130 according to the result of the determination based on predetermined determination conditions. In this embodiment, the determination unit 133 controls the drive power of the motor 12 by the power variable unit 130, assuming that a necessary condition is that the result of comparing the current value detected by the current detection unit 131 with a predetermined threshold value remains the same for a predetermined determination time or longer.

[0024] The control of the driving power of the motor 12 includes an increase control for increasing the driving power, a decrease control for decreasing the driving power, and a protection control.

[0025] The increase control is a control that aims to increase the rotation speed or rotation torque of the cleaning element 11 by increasing the rotation speed of the motor 12 from a relatively low state. In this embodiment, the increase control refers to the control means 13 setting the drive power of the motor 12 to a predetermined first drive power greater than 0 using the power variable unit 130. The first drive power is a relatively large drive power among multiple drive powers that can be set by the power variable unit 130, and is a drive power set by a first PWM signal with a relatively large duty ratio, for example, a duty ratio of 100%. Therefore, if the drive power of the motor 12 satisfies the determination condition for the increase control while it is at the first drive power, the drive power of the motor 12 is maintained as is. A necessary condition for implementing the increase control is that the current value of the motor 12 remains greater than a predetermined first threshold value for a predetermined first determination time or longer.

[0026] The reduction control is a control that aims to reduce the rotation speed or rotation torque of the cleaning element 11 by reducing the rotation speed of the motor 12 from a relatively high state. In this embodiment, the reduction control refers to the control means 13 setting the drive power of the motor 12 to a predetermined second drive power greater than 0 using the power variable unit 130. The second drive power is a relatively small drive power among the multiple drive powers that can be set by the power variable unit 130, and is a drive power set by a second PWM signal having a smaller duty ratio than the first PWM signal, preferably a duty ratio of less than 50%. Note that if the drive power of the motor 12 satisfies the determination condition for the reduction control while it is at the second drive power, the drive power of the motor 12 is maintained as is. A necessary condition for implementing the reduction control is that the current value of the motor 12 remains smaller than a predetermined second threshold value for a predetermined second determination time or longer.

[0027] The second threshold value may be the same as or different from the first threshold value. To increase the hysteresis between the increase control and the decrease control, the second threshold value may be set lower than the first threshold value. To prioritize the decrease control for safety reasons, the second threshold value may be set higher than the first threshold value.

[0028] The protective control is intended to protect the motor 12 from damage by reducing the rotational speed of the motor 12 or substantially stopping the motor 12 when the motor 12 is in an abnormal state. For example, the protective control includes lock control, which substantially stops the motor 12 when the motor 12 is locked, i.e., when the motor 12 is forcibly stopped from rotating even while power is being supplied. In this embodiment, the lock control refers to the control unit 13 setting the drive power of the motor 12 to a predetermined third drive power, which is a drive power that is low enough to safely allow a user to touch the cleaning element 11, using the power variable unit 130. The third drive power is the smallest drive power among multiple drive powers that can be set by the power variable unit 130, and has a duty ratio smaller than that of the second PWM signal, e.g., a drive power set by a third PWM signal with a duty ratio of 0%. A necessary condition for executing the lock control is that the current value of the motor 12 remains greater than a predetermined third threshold for a predetermined third determination time or longer.

[0029] Furthermore, the protection control may include temperature protection control, which reduces the drive power of the motor 12 when the motor 12 is in a high temperature state, thereby keeping the rotation speed at least lower than during the increase control. In this embodiment, temperature protection control refers to the control means 13 setting the drive power of the motor 12 to a fourth drive power, which is lower than the first drive power, using the power variable unit 130. The fourth drive power is set by a fourth PWM signal having a smaller duty cycle than the first PWM signal. A necessary condition for implementing temperature protection control is that the current value of the motor 12 remains higher than a predetermined fourth threshold for a predetermined fourth determination time or longer.

[0030] The third threshold and the fourth threshold are greater than the first threshold. The third threshold is greater than the fourth threshold. That is, the relationship is (third threshold)>(fourth threshold)>(first threshold)>(second threshold).

[0031] Furthermore, it is preferable to cancel the temperature protection control and restore operation of the motor 12 once the motor 12, which is operating at the fourth drive power, has sufficiently cooled. Cancellation of the temperature protection control refers to the control unit 13 setting the drive power of the motor 12 to a fifth drive power, which is greater than the fourth drive power, using the power variable unit 130. The fifth drive power is a drive power set by a fifth PWM signal having a duty cycle greater than that of the fourth PWM signal. The fifth drive power may be equal to the first drive power or the second drive power. A necessary condition for canceling the temperature protection control is that the current value of the motor 12 remains below a predetermined fifth threshold for a predetermined fifth determination time or longer. The fifth threshold is greater than the second threshold and / or the first threshold, and less than the fourth threshold. In other words, the relationship is (fourth threshold) > (fifth threshold) > (second threshold) or (fourth threshold) > (fifth threshold) > (first threshold).

[0032] When the motor 12 is operating at the second drive power, it is unlikely that the motor 12 will reach a high temperature, so the temperature protection control and its cancellation may not be performed. In this case, the fourth drive power is set to a drive power greater than the second drive power.

[0033] Furthermore, since it is assumed that the motor 12 is basically in a cold state at the beginning of startup, the first threshold value to the fifth threshold value may be set to be large at the beginning of startup of the electric vacuum cleaner CL or the motor 12, respectively, and to gradually decrease from the beginning of startup until a predetermined elapsed time has elapsed.

[0034] The first to fifth judgment times are each arbitrary, and may all be equal, any three or any two may be equal, or may be different from each other.

[0035] In addition, for each of the increase control, decrease control, lock control, temperature protection control, and release of temperature protection control, multiple sets of judgment conditions, i.e., threshold values ​​and judgment times, may be set, and control may be performed based on these AND conditions or OR conditions.

[0036] When the motor 12 is in a relatively cold state, the current consumption relative to the load tends to increase. Therefore, depending on the cooling effect or cooling state of the motor 12, a discrepancy may occur between the judgment of the judgment unit 133 and the actual state, which may cause the control by the control means 13, particularly the lock control and / or the temperature protection control, to malfunction.

[0037] Therefore, in this embodiment, the above-mentioned determination conditions are changed according to the degree of the cooling effect of the motor 12, taking into account the cooling effect of the motor 12. For this reason, the electric vacuum cleaner CL includes a cooling effect detection means 9 for detecting the cooling effect of the motor 12.

[0038] The cooling effect detection means 9 may be, for example, a temperature sensor that directly or indirectly detects the temperature of the motor 12, which is an internal factor of the cooling effect, or a sensor that detects an external factor of the cooling effect. Examples of external factors that affect the cooling effect of the motor 12 include the driving power or input of the electric blower 3 and / or the amount of air suctioned by the electric blower 3. In this embodiment, the cooling effect detection means 9 detects at least one of the temperature of the motor 12, the driving power of the electric blower 3, and the amount of air suctioned by the electric blower 3.

[0039] Factors that affect the driving power of the electric blower 3 include the operating mode selected by the user, an increase or decrease in the driving power of the electric blower 3 by the main body control unit 8 due to the detection of the type of the part F to be cleaned by the type detection means, an increase or decrease in the driving power of the electric blower 3 by the main body control unit 8 due to the detection of the amount of dust by the dust amount detection means, the voltage of the power supply unit B based on the output from the voltage sensor or the power supply unit B, detection of the temperature of the vacuum cleaner main body 2 by the main body temperature detection means, current limiting of the electric blower 3, other protection, or a reduction in the driving power of the electric blower 3 due to the activation of a safety device, etc.

[0040] The intake air volume of the electric blower 3 can also be expressed as the open / closed state or clogging state of the intake air passage of the electric blower 3. For example, as the intake air passage becomes clogged and the intake air volume decreases, the air around the electric blower 3 becomes thinner, reducing the mechanical load on the rotation of the electric blower 3. This increases the rotation speed of the electric blower 3, and reduces the power consumption of the electric blower 3 for the same phase angle or duty ratio. Therefore, the intake air volume of the electric blower 3 can be estimated by detecting the rotation speed using a rotation speed detection means if the electric blower 3 is a brushless motor, or by estimating the power consumption for the phase angle and / or duty ratio set by the main body control unit 8 if the electric blower 3 is a brushed motor. In this embodiment, to protect the electric blower 3 from overload, if the intake air volume of the electric blower 3 falls below a predetermined air volume threshold due to clogging of the intake air passage including the separation unit 4, a warning is issued to the user, prompting them to clean or maintain the separation unit 4, etc.

[0041] Therefore, the cooling effect detection means 9 may be provided exclusively for carrying out the above control by the control means 13, or may utilize the function of a sensor or the like that is already provided in the vacuum cleaner CL.

[0042] In this embodiment, the control means 13 corrects at least the lock control, and preferably the protection control including the lock control and the temperature protection control, taking into account the cooling effect of the motor 12. The control means 13 predicts the cooling effect of the motor 12 from the detection result of the cooling effect detection means 9, and if it is determined that the cooling effect of the motor 12 is high, the control means 13 tightens the conditions for implementing the protection control of the motor 12 by relatively increasing at least one of the following: a decrease in the current value of the motor 12 used in the comparison and determination for implementing the protection control by the determination unit 133 of the control means 13; an increase in the threshold value, i.e., the third threshold value and / or the fourth threshold value; or an increase in the determination time, i.e., the third determination time and / or the fourth determination time. That is, the greater the cooling effect on the motor 12, the more the current value of the motor 12 is reduced and / or the third threshold and / or the fourth threshold are increased, thereby relatively increasing the difference between the current value of the motor 12 and the third threshold and / or the fourth threshold. By performing a determination using the value obtained by multiplying the corrected value, it becomes less likely that the current value of the motor 12 has exceeded the third threshold and / or the fourth threshold. Furthermore, the greater the cooling effect on the motor 12, the more the third judgment time and / or the fourth judgment time are increased, and by performing a determination using the value obtained by multiplying the corrected value, it becomes less likely that a determination is made that the current value of the motor 12 has continued to exceed the third threshold and / or the fourth threshold. Therefore, in a situation where the cooling effect on the motor 12 is expected to be relatively high, protective control of the motor 12 is less likely to be triggered compared to a situation where the cooling effect is expected to be low.

[0043] In the following, "when it is determined that the cooling effect on the motor 12 is high" refers not only to the case where the detection result of the cooling effect detection means 9 is compared with a threshold value by software, but also to the case where a circuit or the like is switched depending on the detection result of the cooling effect detection means 9.

[0044] Furthermore, in this embodiment, the control means 13 performs corrections to the increase control and decrease control taking into account the cooling effect of the motor 12. The control means 13 predicts the cooling effect of the motor 12 from the detection result of the cooling effect detection means 9, and when it is determined that the cooling effect of the motor 12 is high, the control means 13 tightens the conditions for performing the increase control of the motor 12 and relaxes the conditions for performing the decrease control of the motor 12 by relatively increasing the degree of decrease correction of the current value of the motor 12 used in the comparison determination for performing the increase control and decrease control by the determination unit 133 of the control means 13 and / or increasing the degree of increase correction of the thresholds, i.e., the first threshold and the second threshold. That is, the higher the cooling effect on the motor 12, the more the current value of the motor 12 is reduced and / or the first threshold is increased, thereby relatively increasing the difference between the current value of the motor 12 and the first threshold, making it less likely that the current value of the motor 12 has exceeded the first threshold, and the second threshold is increased, thereby relatively decreasing the difference between the current value of the motor 12 and the second threshold, and by making a determination based on this corrected value, it becomes more likely that the current value of the motor 12 has fallen below the second threshold. Therefore, in a situation where the cooling effect on the motor 12 is expected to be relatively high, the increase control of the motor 12 is less likely to occur and the decrease control is more likely to occur, compared to a situation where the cooling effect is expected to be low.

[0045] Furthermore, when it is possible to cancel the temperature protective control, the control means 13 corrects the cancellation of the temperature protective control by taking into account the cooling effect of the motor 12. The control means 13 predicts the cooling effect of the motor 12 from the detection result of the cooling effect detection means 9, and when it is determined that the cooling effect of the motor 12 is high, the control means 13 relaxes the conditions for canceling the temperature protective control of the motor 12 by relatively increasing the degree of reduction correction of the current value of the motor 12 and / or the degree of increase correction of the threshold value, i.e., the fifth threshold value, used in the comparison determination for canceling the temperature protective control by the determination unit 133 of the control means 13. In other words, the higher the cooling effect of the motor 12, the more the current value of the motor 12 is reduced and / or the fifth threshold value is increased, thereby relatively reducing the difference between the current value of the motor 12 and the fifth threshold value, and by making a determination using the corrected value, it becomes more likely that the current value of the motor 12 has fallen below the fifth threshold value. Therefore, the situation where the cooling effect on the motor 12 is expected to be relatively high makes it more likely that the temperature protection control for the motor 12 will be released, compared to a situation where the cooling effect is expected to be low.

[0046] The amount of each of the above corrections may be calculated using a function that uses the degree of cooling effect of the motor 12 detected by the cooling effect detection means 9 as at least one variable, or may be determined by referring to a table or the like in which correction amounts are predetermined corresponding to a plurality of correction thresholds based on the comparison results with the correction thresholds. The correction amount is not limited to an addition or subtraction value, but may also be a multiplication value. In other words, instead of adding or subtracting a numerical value to or from the correction value, the correction value may be increased or decreased by multiplying it by a value greater than or equal to 1 or by a value less than 1.

[0047] Next, the operation of one embodiment will be described.

[0048] When cleaning, the user grasps the handheld operating unit 6 and operates the switch 7, causing the main body control unit 8 to operate the electric blower 3. The negative pressure generated by the operation of the electric blower 3 acts on the extension tube 5 and the cleaning tool 1 via the separation unit 4, and dust on the area to be cleaned F is sucked into the separation unit 4 together with air through the dust collection port 100.

[0049] The control means 13 also activates the motor 12 of the cleaning tool 1 using the power variable unit 130 to drive the cleaning element 11. As the cleaning element 11 is driven, dust on the area to be cleaned F is stirred up, and the stirred-up dust is sucked into the separating unit 4 by the negative pressure acting on the dust collection port 100. At this time, the control means 13 operates the motor 12 using a PWM signal corresponding to, for example, the operating mode of the electric blower 3 or the driving force set by the user. Note that the user can stop the operation of the cleaning element 11 of the cleaning tool 1 by operating the switch 7 as necessary, for example, to prevent an object from being caught in the cleaning element 11.

[0050] The user places the cleaning tool 1 on the area to be cleaned F and moves it back and forth alternately using the hand-operated control unit 6, thereby successively sucking dust from the area to be cleaned F into the separation unit 4. The dust-containing air sucked into the separation unit 4 is separated and collected in the separation unit 4. The air from which the dust has been separated cools the electric blower 3 and is then discharged outside the vacuum cleaner body 2.

[0051] During operation of the motor 12, the control means 13 judges the state of the cleaning body 11 and the motor 12 in the judgment unit 133 based on the result of comparing the magnitude of a predetermined current value of the motor 12 detected by the current detection unit 131 with a predetermined threshold value of the current value in the judgment conditions, and the result of comparing the magnitude of the duration with a predetermined judgment time (time threshold value).

[0052] In this embodiment, the "predetermined current value of the motor 12" refers to a current value within a predetermined short time from the time of determination, i.e., the most recent current value, and preferably uses the most recent current value, but is not limited to this. It may also be the current value immediately prior to the latest current value, i.e., the most recent current value stored in the memory unit 132, i.e., the current value one detection cycle before the current value of the motor 12 by the current detection unit 131 from the time of determination. Furthermore, the immediately prior current value refers to the current value stored in the memory unit 132 that is closest to the predetermined current value, i.e., the current value one detection cycle before the predetermined current value, but is not limited to this. It may also be a past current value within a sufficiently short predetermined time, such as two or three detection cycles before the predetermined current value, or a value calculated from multiple immediately prior current values, such as the average current value within a predetermined time from the predetermined current value.

[0053] Then, when the determining unit 133 determines that a predetermined determination condition is satisfied while the motor 12 is operating, the control means 13 controls the drive power of the motor 12 using the power varying unit 130.

[0054] For example, the control means 13 performs an increase control when the current value of the motor 12 remains greater than the first threshold value for a first determination time or longer, such as when the area to be cleaned F detected by the type detection means is a floor surface with a relatively large rotational load, such as a carpet.

[0055] In addition, the control means 13 performs reduction control when the current value of the motor 12 remains below the second threshold value for a second judgment time or longer, for example, when the area to be cleaned F detected by the type detection means is a floor surface with a relatively small rotational load, such as a wooden floor (flooring).

[0056] Furthermore, the control means 13 performs lock control when the current value of the motor 12 remains equal to or greater than the third threshold value for a third determination time or longer, for example, when cloth, paper, or the like is caught in the cleaning element 11.

[0057] In addition, when the current value of the motor 12 remains above the fourth threshold for a fourth judgment time or longer, such as when the outside air temperature is high and the rotation load remains high, the control means 13 determines that the temperature of the motor 12 is high and performs temperature protection control.

[0058] In this case, for example, with regard to lock control and / or temperature protection control, normally, in order to ensure that control is applied reliably, the third threshold and / or fourth threshold and / or the third judgment time and / or the fourth judgment time are set assuming the worst-case conditions for the motor 12, i.e., a situation in which the cooling effect on the motor 12 is lowest and the temperature is most likely to rise (for example, a situation in which the separation section 4, dust collection port 100, etc. are blocked). However, under normal usage conditions, the temperature of the motor 12 does not rise as high as in the worst-case conditions as described above, and the current value of the motor 12 is often high, so that the conditions are met during normal cleaning, and the lock control and / or temperature protection control are activated unnecessarily, causing the cleaning body 11 and / or motor 12 to stop frequently, which may cause inconvenience to the user.

[0059] Therefore, in this embodiment, the control unit 13 corrects at least the lock control, preferably the protection control including the lock control and the temperature protection control, by referring to the detection result by the cooling effect detection unit 9. That is, the control unit 13 predicts the cooling effect on the motor 12, and if it determines that the cooling effect on the motor 12 is high, the control unit 13 relatively increases at least one of the following: a decrease in the current value of the motor 12 used for comparison in the determination unit 133 of the control unit 13; an increase in the third threshold value and / or the fourth threshold value; and an increase in the third determination time and / or the fourth determination time, thereby tightening the conditions for implementing the protection control for the motor 12, and determining whether or not to implement the protection control based on the tightened conditions. Therefore, even if time has passed since the operation of the vacuum cleaner CL or the start of the motor 12, if the motor 12 has cooled down, excessive protection is prevented by adjusting the lock control and / or the temperature protection control so that they are relatively less likely to be applied, thereby suppressing the phenomenon of frequent stopping of the cleaning element 11 and / or the motor 12. On the other hand, if the motor 12 is not cooled, the lock control and / or temperature protection control is adjusted to be relatively more likely to be activated, thereby appropriately protecting the motor 12. Therefore, the motor 12 can be appropriately controlled according to the temperature condition of the motor 12.

[0060] Furthermore, in this embodiment, when it is determined that the cooling effect on motor 12 is high, the conditions for implementing the increase control are tightened by relatively increasing at least one of the decrease correction of the current value of motor 12 used for comparison in determination unit 133 of control means 13 and the increase correction of the first threshold value and the second threshold value, and the conditions for implementing the decrease control and the release of the temperature protection control of motor 12 are relaxed. Therefore, even if time has passed since operation of vacuum cleaner CL or start-up of motor 12, if motor 12 has cooled down, adjustment is made so that the increase control is relatively unlikely to be applied and the release of the decrease control and the temperature protection control is relatively likely to be applied, and if motor 12 has not cooled down, adjustment is made so that the increase control is relatively likely to be applied and the release of the decrease control and the temperature protection control is relatively unlikely to be applied, thereby making it possible to control motor 12 appropriately according to the temperature condition of motor 12.

[0061] In particular, when the average value of the current value of motor 12 or its correlation value is used as the current value of motor 12 used for the judgment by judgment unit 133, fluctuations in the current value of motor 12 are suppressed, and there is a tendency for a judgment to be made that the state in which the threshold value has been exceeded continues.Therefore, by applying a correction according to the cooling effect of motor 12, motor 12 can be appropriately controlled according to the temperature conditions of motor 12.

[0062] For example, if the current value or threshold value of the motor 12 used for comparison in the determination unit 133 of the control means 13 is corrected according to the cooling effect, the relative magnitude relationships between the first through fifth threshold values ​​are basically maintained. On the other hand, even if the relative magnitude relationships between the first through fifth threshold values ​​are maintained, if the relative magnitude relationships between the first through fifth threshold values ​​are not appropriately set, there is a concern that, for example, the conditions for implementing the temperature protective control and the conditions for canceling the temperature protective control may be reversed. Therefore, when the control means 13 determines that the cooling effect on the motor 12 is high, the control means 13 adjusts the determination times used for comparison in the determination unit 133 of the control means 13, for example, the fourth and fifth determination times, to appropriately maintain the priority relationship between implementing the temperature protective control and canceling the temperature protective control.

[0063] For example, motor 12 is cooled by taking in outside air as electric blower 3 is driven. Therefore, it can be said that the greater the driving power and / or the greater the air intake volume of electric blower 3, the more outside air is taken into motor 12, and the easier it is to cool motor 12. Therefore, by using the driving power of electric blower 3 or the air intake volume of electric blower 3 as at least one factor in determining the cooling effect on motor 12, it becomes possible to appropriately predict the cooling effect on motor 12.

[0064] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention to these embodiments. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0065] CL vacuum cleaner 3 Electric blower 11 Cleaning body 12 motors 13 Control measures

Claims

1. An electric blower, a motor that drives the cleaning body; a control means for controlling the operation of the motor; The control means controls the drive power of the motor on the condition that the result of comparing the motor current value or a value related thereto with a predetermined threshold value remains the same for a predetermined determination time or longer, and when it is determined that the cooling effect on the motor is high, the control means tightens the conditions for implementing protection control of the motor by relatively increasing at least one of the reduction correction of the motor current value or a value related thereto used in the comparison, the increase correction of the threshold value, and the increase correction of the determination time. A vacuum cleaner characterized by:

2. When it is determined that the cooling effect on the motor is high, the control means tightens the conditions for implementing control to increase the drive power of the motor by relatively increasing at least one of the reduction correction of the motor current value or its related value used in the comparison and the increase correction of the threshold value, and relaxes the conditions for implementing control to reduce the drive power of the motor and release the protection control of the motor.

2. The vacuum cleaner according to claim 1.

3. When it is determined that the cooling effect on the motor is high, the control means relatively increases the increase correction of the judgment time used in the comparison, thereby maintaining the priority relationships in the plurality of controls of the motor.

3. The vacuum cleaner according to claim 2.

4. The related value or the threshold value includes a value corrected by tightening the condition or relaxing the condition.

4. The vacuum cleaner according to claim 1, wherein the vacuum cleaner comprises:

5. The magnitude of the driving power of the electric blower is at least one factor in determining the magnitude of the cooling effect on the motor.

4. The vacuum cleaner according to claim 1, wherein the vacuum cleaner comprises:

6. The amount of air intake by the electric blower is at least one factor in determining the amount of cooling effect on the motor.

4. The vacuum cleaner according to claim 1, wherein the vacuum cleaner comprises:

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