Electric dust collector

Abstract

The invention provides an electric dust collector which can properly control a motor according to the temperature condition of the motor. An electric vacuum cleaner is provided with an electric blower, a motor (12) for driving a cleaning body, and a control unit (13) for controlling the operation of the motor (12). The control means (13) controls the driving power of the motor (12) using, as a necessary condition, a condition in which a state in which the current value of the motor (12) or a related value thereof is the same as a predetermined threshold value continues for a predetermined determination time or longer, and controls the driving power of the motor (12) when it is determined that the cooling effect on the motor (12) is high. By relatively increasing at least one of the reduction correction of the current value of the motor (12) used in the comparison or the related value thereof, the increase correction of the threshold value, and the increase correction of the determination time, the conditions used for implementing the protection control of the motor (12) are made strict.

Description

Technical Field

[0001] Embodiments of the present invention relate to an electric vacuum cleaner having a motor for vacuuming a part to be vacuumed. Background Technology

[0002] Traditionally, electric vacuum cleaners have used a suction inlet with an active brush structure, where a rotating cleaning body is rotated by a motor. In such a suction inlet, the rotating cleaning body, driven by the motor, temporarily gathers dust from the surface being vacuumed and then sucks it in, thus efficiently removing dust from surfaces where dust easily gets tangled, such as carpets.

[0003] Considering safety and energy efficiency, the rotating cleaning body is preferably suppressed or stopped rotating when it leaves the surface being cleaned. On the other hand, in situations where dust removal performance of the suction inlet is required, such as on carpets, it is preferable that the rotating cleaning body rotates with sufficient torque. Therefore, an electric vacuum cleaner is known that, when the motor is driven, reduces the motor's driving power when a comparison value based on the motor's current consumption remains below a predetermined threshold for a specified period of time, and increases the motor's driving power to increase torque when the comparison value exceeds the predetermined threshold, such as when the suction inlet is on a carpet.

[0004] In addition, there are known electric vacuum cleaners that, when the suction inlet is placed on a carpet with a long pile or when a cloth or other object is rolled into the rotating cleaning body, if the motor locks and a very large current flows, there is a risk of component damage. Therefore, the current consumption of the motor is constantly monitored, and when it is determined that the current consumption exceeds a specified threshold for a specified period of time, it is determined that the motor rotation is locked and the motor drive is stopped.

[0005] However, motors tend to consume more current to a load at low temperatures and less current to a load at high temperatures. In a structure that controls motor operation based on current variations, as described above, if the threshold is fixed, it is assumed that temperature conditions affect the decisions used for control. Therefore, in order to reliably make decisions on current variations and differences caused by temperature differences that are highly correlated with the rotating load of the rotating cleaning body or motor, the aforementioned control or decision is maintained for a certain period of time during the initial startup phase when the motor is considered to be cold, or the decision conditions used for control are modified for a certain period of time from the start of operation when the external temperature is low during motor startup.

[0006] However, even after a certain period of time has passed since the start of the operation, the motor is cooled by the suction air from the electric blower during the vacuuming operation, so it is desirable to implement appropriate control.

[0007] Patent Document 1: Japanese Patent Application Publication No. 2022-68680

[0008] Patent Document 2: Japanese Patent Application Publication No. 2024-77208 Summary of the Invention

[0009] The problem to be solved by the present invention is to provide an electric vacuum cleaner that can appropriately control the motor according to the motor temperature conditions.

[0010] The electric vacuum cleaner of the embodiment includes an electric blower, a motor that drives the cleaning body, and a control unit that controls the operation of the motor. The control unit controls the motor drive power when it is necessary that the state in which the result of comparing the motor current value or its associated value with a predetermined threshold is the same for a predetermined determination time or more. Furthermore, when it is determined that the cooling effect on the motor is high, the control unit tightens the conditions for implementing motor protection control by relatively increasing at least one of the following: a reduction correction for the motor current value or its associated value used for comparison, an increase correction for the threshold, and an increase correction for the determination time.

[0011] Based on the above electric vacuum cleaner, the motor can be appropriately controlled according to the motor temperature conditions. Attached Figure Description

[0012] Figure 1 This is a block diagram illustrating the internal structure of a portion of an electric vacuum cleaner according to one embodiment.

[0013] Figure 2 This is a schematic cross-sectional view of the cleaning tool of the aforementioned electric vacuum cleaner.

[0014] Figure 3 This is a three-dimensional diagram representing the aforementioned electric vacuum cleaner.

[0015] Explanation of symbols

[0016] CL: Electric vacuum cleaner; 3: Electric blower; 11: Sweeping body; 12: Motor; 13: Control unit Detailed Implementation

[0017] Hereinafter, one embodiment will be described with reference to the accompanying drawings.

[0018] exist Figure 1 and Figure 2In this document, 1 represents a cleaning tool. The cleaning tool 1, also known as a vacuum head, is used to vacuum the surface to be vacuumed, such as the floor, specifically the vacuuming part F. The cleaning tool 1 includes a housing 10. A dust collection port 100 is formed on the housing 10. Furthermore, a cleaning body 11 is disposed within the housing 10. In this embodiment, a rotating cleaning body is used as an example. The cleaning body 11 is driven by a motor 12 to gather dust from the vacuuming part F towards the dust collection port 100. In this embodiment, the cleaning body 11 is mounted on the dust collection port 100. The motor 12 is controlled by a control unit 13. Additionally, in the cleaning tool 1, a connecting pipe 14, serving as a connecting part, is connected to the housing 10. The connecting pipe 14 communicates with the dust collection port 100.

[0019] like Figure 3 As shown, the cleaning tool 1 is used in an electric vacuum cleaner CL. In this embodiment, the cleaning tool 1 is applied to a suction-type electric vacuum cleaner CL that uses negative pressure generated by the suction source, i.e., the electric blower 3, which is disposed in the vacuum cleaner body 2 of the electric vacuum cleaner CL, to suck dust and air together into the separation section 4. The electric vacuum cleaner CL can be any type of vacuum cleaner, such as a floor-mounted, cantilever, stick, upright, handheld, or self-propelled electric vacuum cleaner. In this embodiment, a stick-type electric vacuum cleaner will be used as an example to describe the electric vacuum cleaner CL. In the illustrated example, the cleaning tool 1 is also referred to as the suction inlet or floor brush, and is mechanically and fluidly connected to the vacuum cleaner body 2 via the connecting pipe 14, either indirectly or directly, through the extension pipe 5, which is a pipe section. The suction side of the electric blower 3 is connected to the dust collection port 100 via the separation section 4 through the connecting pipe 14. In addition, the motor 12 inside the cleaning tool 1 ( Figure 2The motor 12 (shown) is also located in an air duct that is independently connected to the suction side of the electric blower 3 from the dust collection port 100, and uses the external air drawn in by the operation of the electric blower 3 to cool the motor 12. However, the motor 12 may also be located in an air duct via the dust collection port 100. Furthermore, in this embodiment, the operation of the electric blower 3, its suction power, or its operating intensity (e.g., strong mode, weak mode), and the on / off state of the rotation of the cleaning body 11 or the motor 12 are set by the user through the operation of the switch 7 on the handle, i.e., the hand-held operation unit 6. A main control unit 8 is provided on the vacuum cleaner body 2 to operate the electric blower 3 according to the operation set by the switch 7. The switch 7 or the main control unit 8 is electrically connected to the control unit 13. The control unit 13 may also be located on the cleaning tool 1, but in this embodiment, at least a portion of the control unit 13 is assembled on the main control unit 8. The power supply unit B of the electric vacuum cleaner CL is, for example, located on the vacuum cleaner body 2. In this embodiment, the power supply unit B is a battery or a rechargeable battery, but is not limited to these; it can also be an AC-DC adapter, a cord reel device, or the like that that obtains power from an external power source such as a commercial power supply. Furthermore, in this embodiment, it serves as the power supply unit B to the motor 12 and control unit 13 of the cleaning tool 1. Figure 1 The structure shown is for power supply, but it is not limited to this. Alternatively, the cleaning tool 1 may have a separate motor 12 and control unit 13. Figure 1 The power supply section (as shown).

[0020] Furthermore, in the diagram, 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 left direction, and arrow R indicates the right direction. These directions are based on the view from the opposite side of the user when the electric vacuum cleaner CL is in use.

[0021] Next, refer to Figure 1 and Figure 2 The internal structure of the control unit 13 will be described.

[0022] The control unit 13 includes a power variable unit 130 that allows the drive power of the motor 12 to be variable. The power variable unit 130 can allow the drive power of the motor 12 to be changed steplessly or to any one of multiple levels. In this embodiment, the power variable unit 130 can set the drive power of the motor 12 to at least any one of multiple levels.

[0023] As a method for the variable power unit 130 to make the drive power of the motor 12 variable, for example, the energizing time or the amount of power supplied from the power source to the motor 12 is adjusted, and the drive power of the motor 12 is set according to the energizing time of the motor 12. As an example, the variable power unit 130 sets the control signal applied to the motor 12, i.e., the voltage applied, as a PWM signal, and sets the drive power of the motor 12 by adjusting the duty cycle of the PWM signal. That is, if the duty cycle of the PWM signal is set to 100%, the drive power of the motor 12 is at its maximum; by decreasing the duty cycle of the PWM signal, the drive power of the motor 12 decreases, and the rotational speed and torque of the cleaning body 11 decrease. In other words, the variable power unit 130 increases the duty cycle when the drive power of the motor 12 increases, and decreases the duty cycle when the drive power of the motor 12 decreases. In this embodiment, the variable power unit 130 has multiple different duty cycles, and by selectively setting the duty cycle of the PWM signal of the motor 12 to any one of these duty cycles, multiple different drive power settings for the motor 12 can be achieved.

[0024] The power variable unit 130 can set the drive power of the motor 12 based on the switch 7 ( Figure 3 The power variable unit 130 can switch according to user settings (as shown), the strength of the suction power of the electric blower 3, or the operating mode, or automatically according to the suction status. The suction status refers to, for example, the type of flooring constituting the suctioned part F, or the amount of dust suctioned from the suctioned part F. That is, it can be combined with a suction status detection unit such as a type detection unit that detects the type of suctioned part F and / or a dust quantity detection unit that detects the amount of dust suctioned, and the power variable unit 130 can automatically select and set the drive power of the motor 12. The type detection unit and the dust quantity detection unit can be any known structure. In this embodiment, for example, the power variable unit 130 selectively uses any one of a plurality of PWM signals with duty cycles corresponding to the desired control to set the drive power of the motor 12.

[0025] Additionally, the control unit 13 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 according to a predetermined detection cycle. As an example of the method by which the current detection unit 131 detects the current value of the motor 12, current is allowed to flow through a resistor with a small resistance value, called a shunt resistor, which serves as the detection element. The potential difference generated across the shunt resistor is amplified and input to an A / D converter, which serves as a conversion unit, and the output of the A / D converter is obtained. In this embodiment, the current value detected by the current detection unit 131 is, for example, the load current value. The load current value is the current value that represents the load state of the cleaning body 11 driven by the motor 12, and it is related to the actual current value of the motor 12. The actual current value of the motor 12 is, for example, the average value of the current values ​​obtained a predetermined number of times in a predetermined time period. This actual current value is highly dependent on the duty cycle of the PWM signal of the power variable unit 130. Therefore, in this embodiment, the load current value is, for example, obtained by dividing the actual current value by the duty cycle of the PWM signal in the power variable unit 130. That is, (load current value) = (actual current value) / (duty cycle). Therefore, the load current value in this embodiment is a value calculated based on the current flowing in the motor 12 and the duty cycle.

[0026] In the control and decision-making processes performed by the control unit 13, the current value detected by the current detection unit 131 may be used instead of the current value, or its associated value may be used in addition to the current value. The associated value of the current value includes: the current value flowing in the motor 12 itself; the value obtained by subtracting a predetermined value from the current value flowing in the motor 12; a value that is related to the current value calculated based on the current value flowing in the motor 12; and a value after strictening and / or easing based on the conditions described later. Hereinafter, "the current value of the motor 12 or its associated value" will be simply referred to as "the current value of the motor 12", and "the rotating load of the cleaning body 11 or the motor 12" will be simply referred to as "the rotating load".

[0027] Furthermore, in this embodiment, the current detection unit 131 is described as having a current value acquisition unit that acquires the current value flowing in the motor 12 by having a detection element and an A / D converter, an actual current value calculation unit that calculates the actual current value, and a load current value calculation unit that calculates the load current value. However, the current value acquisition unit, the actual current value calculation unit, and the load current value calculation unit can be configured as separate circuit units, or they can be arbitrarily combined, and some of them can also be part of other circuit units. That is, the current detection unit 131 is not limited to having a current value acquisition unit, an actual current value calculation unit, and a load current value calculation unit as a single unit.

[0028] Furthermore, the control unit 13 includes a storage unit 132, such as a memory. In this embodiment, the storage unit 132 stores current values ​​detected by the current detection unit 131, various threshold values ​​for determination, and determination values. In addition, the storage unit 132 stores other arbitrary thresholds, flags, programs, and other data used for the control of the control unit 13.

[0029] Furthermore, the control unit 13 includes a determination unit 133. The determination unit 133 determines the state of the cleaning tool 1, motor 12, or cleaning body 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 determination result based on predetermined determination conditions. In this embodiment, the determination unit 133 takes as a necessary condition that the state in which the current value detected by the current detection unit 131 is the same as a predetermined threshold value has persisted for a predetermined determination time or more, and controls the drive power of the motor 12 by the power variable unit 130.

[0030] The control of the drive power of motor 12 includes increase control to increase the drive power, decrease control to decrease the drive power, and protection control.

[0031] Increase control is control aimed at increasing the rotational speed or torque of the cleaning body 11 by increasing the rotational speed of the motor 12 from a relatively low state. In this embodiment, increase control means that the control unit 13 sets the drive power of the motor 12 to a predetermined first drive power greater than 0 through the power variable unit 130. The first drive power is a relatively large drive power among a plurality of 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 cycle, for example, a duty cycle of 100%. Therefore, if the determination condition for increase control is met when the drive power of the motor 12 is the first drive power, the drive power of the motor 12 remains unchanged. A necessary condition for implementing increase control is that the current value of the motor 12 is greater than a predetermined first threshold for a predetermined first determination time or longer.

[0032] Reduction control aims to reduce the rotational speed or torque of the sweeper body 11 by decreasing the rotational speed of the motor 12 from a relatively high state. In this embodiment, reduction control refers to the control unit 13 setting the drive power of the motor 12 to a predetermined second drive power greater than 0 via the power variable unit 130. The second drive power is a relatively small drive power among a plurality of drive powers that can be set by the power variable unit 130, and is set by a second PWM signal with a duty cycle less than the first PWM signal, preferably less than 50%. Furthermore, if the determination condition for reduction control is met when the drive power of the motor 12 is the second drive power, the drive power of the motor 12 remains unchanged. A necessary condition for implementing reduction control is that the current value of the motor 12 is less than a predetermined second threshold for a predetermined second determination time or longer.

[0033] The second threshold can be the same as or different from the first threshold. To increase the hysteresis between increasing and decreasing control, the second threshold can be lower than the first threshold; conversely, if decreasing control is prioritized for safety reasons, the second threshold can be higher than the first threshold.

[0034] The protection control aims to protect the motor 12 from damage by suppressing its rotational speed or substantially stopping it when it becomes abnormal. For example, a protection control includes a locking control that substantially stops the motor 12 when it is in a locked state, i.e., its rotation is forcibly stopped even when it is energized. In this embodiment, the locking control refers to the control unit 13 setting the drive power of the motor 12 via the power variable unit 130 to a lower speed drive power that is safe even if the user touches the cleaning body 11, i.e., a predetermined third drive power. The third drive power is the smallest of a plurality of drive powers that can be set by the power variable unit 130, and is set by a third PWM signal with a duty cycle less than the second PWM signal, for example, a duty cycle of 0%. A necessary condition for implementing the locking control is that the current value of the motor 12 is greater than a predetermined third threshold for a predetermined third determination time or longer.

[0035] Furthermore, as a protective control, it may also include temperature protection control: when the motor 12 reaches a high temperature, the drive power of the motor 12 is suppressed to reduce the rotational speed to at least lower than when control is increased. In this embodiment, temperature protection control refers to the control unit 13 setting the drive power of the motor 12 to a fourth drive power, which is lower than the first drive power, via the power variable unit 130. The fourth drive power is the drive power set by a fourth PWM signal with a duty cycle less than the first PWM signal. A necessary condition for implementing temperature protection control is that the current value of the motor 12 is greater than a predetermined fourth threshold for a predetermined fourth determination time or longer.

[0036] The third and fourth thresholds are values ​​greater than the first threshold. The third threshold is greater than the fourth threshold. That is, (third threshold) > (fourth threshold) > (first threshold) > (second threshold).

[0037] Furthermore, the aforementioned temperature protection control is preferably implemented such that if the motor 12, which operates with the fourth drive power, is sufficiently cooled, the control is released, allowing the operation of the motor 12 to resume. Releasing the temperature protection control means that the control unit 13, through the power variable unit 130, sets the drive power of the motor 12 to a fifth drive power that is greater than the fourth drive power. The fifth drive power is a drive power set by a fifth PWM signal with a duty cycle greater than the fourth PWM signal. The fifth drive power can be equal to the first drive power or the second drive power. A necessary condition for releasing the temperature protection control is that the current value of the motor 12 is less than 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. That is, (fourth threshold) > (fifth threshold) > (second threshold), or (fourth threshold) > (fifth threshold) > (first threshold).

[0038] Furthermore, since the motor 12 operates using the second drive power, it is difficult to assume that the motor 12 will become overheated; therefore, temperature protection control and its deactivation may not be implemented. In this case, the fourth drive power is a drive power greater than the second drive power.

[0039] In addition, since it is assumed that the motor 12 is basically in a cooled state at the initial stage of startup, the first threshold to the fifth threshold can also be set to be larger at the initial stage of startup of the electric vacuum cleaner CL or the motor 12, and gradually decrease during the period from the initial stage of startup to the specified elapsed time.

[0040] The first to fifth determination times can be set arbitrarily; they can all be equal, any three or any two can be equal, or they can be different.

[0041] Furthermore, in each of the functions of increasing control, decreasing control, locking control, temperature protection control, and releasing temperature protection control, multiple sets of judgment conditions, i.e., thresholds and judgment times, can be set, and control can be implemented based on their AND and OR conditions.

[0042] Here, if the motor 12 is in a relatively cooled state, it tends to consume a relatively increased current relative to the load. Therefore, depending on the cooling effect or cooling state of the motor 12, the determination of the determination unit 133 may be inconsistent with the actual state, raising concerns that the control unit 13's control, especially the locking control and / or temperature protection control, may not function properly.

[0043] Therefore, in this embodiment, the cooling effect of the motor 12 is also considered, and the above-mentioned determination criteria are modified according to the degree of its cooling effect. Therefore, the electric vacuum cleaner CL is equipped with a cooling effect detection unit 9 for detecting the cooling effect of the motor 12.

[0044] The cooling effect detection unit 9 can be a temperature sensor that directly or indirectly detects the internal element of the cooling effect, namely the temperature of the motor 12, or it can be a sensor that detects the external element of the cooling effect. External elements affecting the cooling effect of the motor 12 include, for example, the driving power or input of the electric blower 3, and / or the intake air volume of the electric blower 3. In this embodiment, the cooling effect detection unit 9 detects at least one of the following: the temperature of the motor 12, the driving power of the electric blower 3, and the intake air volume of the electric blower 3.

[0045] The main reasons affecting the driving power of the electric blower 3 include: the operating mode selected by the user; the increase or decrease of the driving power of the electric blower 3 by the main control unit 8 due to the detection of the type of dust-collecting part F by the type detection unit; the increase or decrease of the driving power of the electric blower 3 by the main control unit 8 due to the detection of the dust amount by the dust amount detection unit; the voltage of the power supply unit B based on the voltage sensor and the output of the power supply unit B; the detection of the temperature of the vacuum cleaner body 2 by the main body temperature detection unit; the current limit of the electric blower 3; other protections; or the reduction of the driving power of the electric blower 3 due to the operation of safety devices.

[0046] Furthermore, the intake air volume of the electric blower 3 can also be described in other words as the open / closed or blocked state of the intake air passage of the electric blower 3. For example, if the intake air passage is blocked and the intake air volume decreases, the air around the electric blower 3 becomes thinner, thus reducing the mechanical load on the rotation of the electric blower 3. Consequently, the rotational speed of the electric blower 3 increases, and the power consumption of the electric blower 3 decreases relative to the same phase angle or duty cycle. Therefore, regarding the intake air volume of the electric blower 3, if the electric blower 3 is a brushless motor, it can be estimated based on the rotational speed detected by the speed detection unit; if the electric blower 3 is a brushed motor, it can be estimated based on the power consumption relative to the phase angle and / or duty cycle set by the main control unit 8. In this embodiment, in order to protect the electric blower 3 from overload, if the intake air volume of the electric blower 3 is less than the specified air volume threshold due to blockage of the intake air passage including the separator 4, a warning can be issued to the user to prompt him to perform maintenance or upkeep of the separator 4, etc.

[0047] Therefore, the cooling effect detection unit 9 can be specially set up for the control unit 13 to implement the above control, or it can utilize the functions of sensors and the like that are pre-installed in the electric vacuum cleaner CL.

[0048] Furthermore, in this embodiment, the control unit 13 makes corrections that take into account the cooling effect of the motor 12, at least for lockout control, and preferably for protection control including lockout control and temperature protection control. The control unit 13 predicts the cooling effect of the motor 12 based on the detection results of the cooling effect detection unit 9. If it is determined that the cooling effect on the motor 12 is high, the control unit 13 relatively increases the degree of at least one of the following corrections used in the comparison determination of the motor 12 for implementing protection control: a reduction correction for the current value of the motor 12, an increase correction for the threshold (i.e., the third threshold and / or the fourth threshold), or an increase correction for the determination time (i.e., the third determination time and / or the fourth determination time). This tightens the conditions for implementing protection control of the motor 12. That is, the higher the cooling effect on the motor 12, the more the current value of the motor 12 decreases and / or the third threshold and / or the fourth threshold increases, thereby relatively increasing the difference between the current value of the motor 12 and the third threshold and / or the fourth threshold. By using the value with this correction applied for determination, it is difficult to produce a determination where the current value of the motor 12 exceeds the third threshold and / or the fourth threshold. Furthermore, the higher the cooling effect on motor 12, the greater the third and / or fourth determination time becomes, and the determination is made using the value with this correction applied. This makes it difficult to determine if the current value of motor 12 continues to exceed the third and / or fourth threshold. Therefore, the more the cooling effect on motor 12 is assumed to be relatively high, the more difficult it is to generate protection control for motor 12 compared to the assumption of a lower cooling effect.

[0049] Furthermore, the following "cases where the cooling effect on motor 12 is deemed to be high" include not only cases where the judgment is made by comparing the detection results of the cooling effect detection unit 9 with the threshold using software, but also cases where the circuit is switched based on the detection results of the cooling effect detection unit 9.

[0050] Furthermore, in this embodiment, the control unit 13 makes corrections to the increase control and decrease control taking into account the cooling effect of the motor 12. The control unit 13 predicts the cooling effect of the motor 12 based on the detection results of the cooling effect detection unit 9. If it is determined that the cooling effect of the motor 12 is high, the control unit 13 relatively increases the degree of the decrease correction of the current value of the motor 12 used in the comparison determination for implementing increase control and decrease control in the determination unit 133 of the control unit 13, and / or the increase correction of the threshold, namely the first threshold and the second threshold. This tightens the conditions for implementing increase control of the motor 12 and eases the conditions for implementing decrease control of the motor 12. That is, the higher the cooling effect on motor 12, the lower the current value of motor 12 and / or the higher the first threshold value. This relatively increases the difference between the current value of motor 12 and the first threshold value, making it difficult to determine that the current value of motor 12 exceeds the first threshold value. Furthermore, by increasing the second threshold value, the difference between the current value of motor 12 and the second threshold value relatively decreases. When the determination is made using the value with this correction applied, it is easier to determine that the current value of motor 12 is lower than the second threshold value. Therefore, the more the cooling effect on motor 12 is assumed to be relatively high, the more difficult it is to increase motor 12 control and the easier it is to decrease it compared to assuming a lower cooling effect.

[0051] Furthermore, when the temperature protection control can be released, the control unit 13 corrects the release of the temperature protection control by taking into account the cooling effect of the motor 12. The control unit 13 predicts the cooling effect of the motor 12 based on the detection results of the cooling effect detection unit 9. If it determines that the cooling effect on the motor 12 is high, it relatively increases the degree of the reduction correction of the motor 12 current value and / or the increase correction of the threshold (i.e., the fifth threshold) used in the determination unit 133 for implementing the release of the temperature protection control. This eases the conditions for implementing the release of the temperature protection control on the motor 12. That is, the higher the cooling effect on the motor 12, the more the current value of the motor 12 decreases and / or the fifth threshold increases, thereby relatively reducing the difference between the current value of the motor 12 and the fifth threshold. The determination is made using the value with this correction applied, making it easier to determine that the current value of the motor 12 is lower than the fifth threshold. Therefore, the more the assumption of a relatively high cooling effect on the motor 12 is compared to the assumption of a low cooling effect, the easier it is to release the temperature protection control on the motor 12.

[0052] Regarding the correction amounts for each of the above corrections, they can be calculated as a function of the degree of cooling effect of the motor 12 detected by the cooling effect detection unit 9 as at least one variable, or they can be determined based on comparison results with multiple correction thresholds, or by referring to a table in advance where the correction amounts are predetermined corresponding to these correction thresholds. The correction amount is not limited to additive or subtractive values; it can also be a multiplicative value. That is, instead of adding or subtracting a value, the correction value can be multiplied by a value greater than 1 or less than 1, thereby increasing or decreasing the correction value.

[0053] Next, the operation of one implementation method will be described.

[0054] When vacuuming, the user holds the control unit 6 and operates the switch 7, thereby causing the main 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 through the separation unit 4, thereby drawing the dust and air from the vacuuming unit F into the separation unit 4 through the dust collection port 100.

[0055] Furthermore, the control unit 13 starts the motor 12 of the cleaning tool 1 via the power variable unit 130, thereby driving the cleaning body 11. Driven by the cleaning body 11, dust from the suction unit F is gathered, and this gathered dust is sucked into the separation unit 4 by the negative pressure acting on the dust collection port 100. At this time, the control unit 13 uses, for example, a PWM signal corresponding to the operating mode of the electric blower 3 and the driving force set by the user to operate the motor 12. In addition, the user can operate the switch 7 to stop the operation of the cleaning body 11 of the cleaning tool 1 as needed, such as to prevent the cleaning body 11 from getting caught in objects.

[0056] The user moves the cleaning tool 1 back and forth alternately while it is placed on the dust-collecting part F using the hand-held operating unit 6, thereby sequentially sucking the dust on the dust-collecting part F into the separation unit 4. The dust-laden air sucked into the separation unit 4 is separated and the dust is captured in the separation unit 4. After the dust is separated, the air is cooled by the electric blower 3 and then discharged to the outside of the vacuum cleaner body 2.

[0057] During the operation of the motor 12, the control unit 13 determines the state of the cleaning body 11 and the motor 12 based on the comparison result between the specified current value of the motor 12 detected by the current detection unit 131 in the determination unit 133 and the specified threshold of the current value in the determination condition, and the comparison result between its duration and the specified determination time (time threshold).

[0058] In this embodiment, "the specified current value of the motor 12" refers to the most recent current value within a specified short period of time from the time of determination. Preferably, the latest current value is used, but it is not limited to this. It could also be the current value immediately preceding the latest current value, the latest current value stored in the storage unit 132, or the current value one detection cycle before the current detection unit 131 detects the current value of the motor 12 from the time of determination. Furthermore, the immediately preceding current value is the past current value stored in the storage unit 132 that is closest to the specified current value, i.e., the current value one detection cycle from the specified current value. However, it is not limited to this. It could also be a past current value within a sufficiently short specified time, such as two or three detection cycles from the specified current value, or a value calculated based on multiple immediately preceding current values, such as the average of current values ​​within a specified time from the specified current value.

[0059] Furthermore, when the determination unit 133 determines that the predetermined determination conditions are met during the operation of the motor 12, the control unit 13 controls the drive power of the motor 12 through the power variable unit 130.

[0060] For example, if the type detection unit detects that the dust-collected part F is a carpet or other surface with a relatively large rotational load, the control unit 13 will increase control if the current value of the motor 12 has been greater than the first threshold for more than a first determination time.

[0061] In addition, for example, if the dust-collecting part F detected by the type detection unit is a floor with relatively small rotational load, such as a wooden floor, the control unit 13 performs a reduction control when the current value of the motor 12 has been less than the second threshold for more than a second determination time.

[0062] In addition, if, for example, cloth, paper, or the like gets caught in the cleaning body 11, the control unit 13 performs locking control when the current value of the motor 12 is above the third threshold for a third determination time or more.

[0063] In addition, when the external temperature is high and the rotating load is high, the control unit 13 determines that the temperature of the motor 12 is high and performs temperature protection control when the current value of the motor 12 is above the fourth threshold for more than the fourth determination time.

[0064] At this time, for example, regarding lock-up control and / or temperature protection control, in order to reliably apply control, the worst-case conditions for motor 12 are assumed, that is, the conditions where the cooling effect on motor 12 is the lowest and the temperature is most likely to rise (e.g., the separation section 4, dust collection port 100, etc. are blocked), and the third threshold and / or fourth threshold, and / or third determination time and / or fourth determination time are set. However, under normal use conditions, the temperature of motor 12 will not rise to the level of the worst-case conditions as described above, and the current value of motor 12 will increase more often. Therefore, the conditions may be met during normal vacuuming, and lock-up control and / or temperature protection control may be generated unnecessarily. The cleaning body 11 and / or motor 12 will stop frequently, which will be inconvenient for the user.

[0065] Therefore, in this embodiment, the control unit 13, by referring to the detection results of the cooling effect detection unit 9, at least corrects the lock-in control, and preferably the protection control including lock-in control and temperature protection control. 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, it relatively increases at least one of the following: a reduction correction for the current value of the motor 12 used in the comparison of the determination unit 133 of the control unit 13; an increase correction for the third threshold and / or the fourth threshold; and an increase correction for the third determination time and / or the fourth determination time. This tightens the conditions for implementing protection control of the motor 12, and determines whether protection control needs to be implemented based on the tightened conditions. Therefore, by adjusting the system so that even if time has elapsed since the operation of the electric vacuum cleaner CL or the start-up of the motor 12, it is relatively difficult to apply lock-in control and / or temperature protection control when the motor 12 is cooling down, excessive protection is prevented, and the phenomenon of frequent stops of the cleaning body 11 and / or the motor 12 is suppressed. On the other hand, by adjusting the system so that locking control and / or temperature protection control can be applied relatively easily when the motor 12 is not cooled, the motor 12 can be properly protected. Therefore, the motor 12 can be appropriately controlled according to its temperature conditions.

[0066] Furthermore, in this embodiment, when it is determined that the cooling effect on the motor 12 is high, by relatively increasing at least one of the reduction correction of the motor 12 current value used in the comparison of the determination unit 133 of the control unit 13, and the increase correction of the first threshold and the second threshold, the conditions for implementing the increase control are tightened, while the conditions for implementing the decrease control and releasing the temperature protection control of the motor 12 are relaxed. Therefore, by adjusting the system so that even if time has elapsed since the operation of the electric vacuum cleaner CL or the start-up of the motor 12, it is relatively difficult to apply the increase control when the motor 12 is cooled, and it is relatively easy to apply the decrease control and release the temperature protection control, and by adjusting the system so that it is relatively easy to apply the increase control when the motor 12 is not cooled, and it is relatively difficult to apply the decrease control and release the temperature protection control, the motor 12 can be appropriately controlled according to the temperature conditions of the motor 12.

[0067] In particular, when the average value of the current value of the motor 12 or its related value is used as the current value of the motor 12 used in the determination of the determination unit 133, the variation of the current value of the motor 12 is suppressed, and there is a tendency to be easily determined that the state of exceeding the threshold has continued. Therefore, by applying a correction based on the cooling effect of the motor 12, the motor 12 can be appropriately controlled according to the temperature conditions of the motor 12.

[0068] For example, when the current value and threshold of the motor 12 used in the comparison of the determination unit 133 of the control unit 13 are corrected according to the cooling effect, the magnitude relationship between the first threshold to the fifth threshold is basically maintained. On the other hand, even if the magnitude relationship between the first threshold to the fifth threshold is maintained, if the magnitude relationship between the first determination time to the fifth determination time is not properly set, there is a concern that the conditions for implementing temperature protection control and the conditions for releasing temperature protection control may be reversed. Therefore, when the control unit 13 determines that the cooling effect on the motor 12 is high, it can appropriately maintain the priority relationship between the implementation of temperature protection control and the release of temperature protection control by adjusting the determination time used in the comparison of the determination unit 133 of the control unit 13, such as the fourth determination time and the fifth determination time.

[0069] For example, the motor 12 draws in external air and is cooled by the electric blower 3. Therefore, it can be said that the greater the driving power of the electric blower 3 and / or the greater the air intake, the easier it is to draw in more external air and cool the motor 12. Therefore, by setting the magnitude of the driving power of the electric blower 3 or the magnitude of the air intake of the electric blower 3 as at least one factor affecting the cooling effect on the motor 12, the cooling effect of the motor 12 can be appropriately predicted.

[0070] 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 to these embodiments. These new 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 in the scope and spirit of the invention, and are included in the scope of the invention as described in the claims and its equivalents.

Claims

1. An electric vacuum cleaner, characterized in that, have: Electric blower; The motor that drives the sweeping body; and The control unit that controls the motor's movement. The control unit controls the motor's drive power as a necessary condition if the state in which the comparison between the motor's current value or its associated value and a predetermined threshold is the same continues for a predetermined determination time or more. Furthermore, if it is determined that the cooling effect on the motor is high, the control unit tightens the conditions for implementing the motor's protective control by relatively increasing at least one of the following: a reduction correction for the motor's current value or its associated value used in the comparison, an increase correction for the threshold, and an increase correction for the determination time.

2. The electric vacuum cleaner according to claim 1, characterized in that, The control unit, when it is determined that the cooling effect on the motor is high, tightens the conditions for implementing control that increases the drive power of the motor by relatively increasing at least one of the reduction correction of the current value of the motor or its associated value used in the comparison and the increase correction of the threshold, and eases the conditions for implementing control that decreases the drive power of the motor and releasing the protection control of the motor.

3. The electric vacuum cleaner according to claim 2, characterized in that, The control unit, when determining that the cooling effect on the motor is high, maintains the priority relationship of multiple controls of the motor by relatively increasing the determination time used in the comparison.

4. The electric vacuum cleaner according to any one of claims 1 to 3, characterized in that, The associated value or the threshold includes a value modified by tightening or easing the condition.

5. The electric vacuum cleaner according to any one of claims 1 to 3, characterized in that, The magnitude of the driving power of the electric blower is used as at least one factor in determining the magnitude of the cooling effect on the motor.

6. The electric vacuum cleaner according to any one of claims 1 to 3, characterized in that, The magnitude of the intake air volume of the electric blower is used as at least one factor in determining the magnitude of the cooling effect on the motor.

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