JP2004195105A - Vacuum cleaner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum cleaner in which a motor-driven air blower can be securely protected. <P>SOLUTION: A control means 24 carries out the duty control of the voltage of a commercial ac current supply E to keep the electric current of a motor-driven air motor 2 at a constant value. When the on-duty of the motor-driven blower 2 is lowered than a predetermined value, the on-duty value of the motor-driven air motor 2 is raised to 100% to fusion cut a fuse 21. The state of the motor-driven air blower 2 can be securely detected even while the electric current value of the motor-driven air blower 2 is kept constant. The motor-driven air blower 2 can be also protected securely even when the motor-driven air blower is locked. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric vacuum cleaner in which a voltage of a power supply is duty-controlled to make a current value of an electric blower constant.
[0002]
[Prior art]
A conventional vacuum cleaner includes an electric blower that forms a closed circuit with a power supply. The electric blower is connected to current detecting means for detecting a current of the electric blower. The electric blower is connected to control means for controlling electric power supplied from a power supply to the electric blower. Further, a fuse is provided in a closed circuit between the power supply and the electric blower. Then, for example, in a state where the electric blower cannot be driven due to a foreign object being caught on the electric blower, for example, when the electric blower is locked, a voltage value corresponding to the current value of the electric blower detected by the current detecting means is preset. If the voltage is larger than the voltage threshold corresponding to the current threshold, the fuse is blown by the control means to electrically open the circuit between the power supply and the electric blower, thereby protecting the electric blower (for example, see Patent Document 1). 1).
[0003]
[Patent Document 1]
JP-A-9-206255 (page 3-4, FIGS. 3 to 5)
[0004]
[Problems to be solved by the invention]
However, in the above-described vacuum cleaner, the lock of the electric blower is detected at a preset voltage threshold. For this reason, for example, when the power supply supplied to the electric blower is duty-controlled to make the current value of the electric blower constant and to reduce the power consumption of the electric vacuum cleaner, the voltage of the electric blower is reduced even if the electric blower is locked. It is suppressed below a preset threshold, and it is not easy to detect the lock of the electric blower.
[0005]
As a result, there is a problem that protection of the electric blower is not reliable.
[0006]
The present invention has been made in view of such a point, and an object of the present invention is to provide a vacuum cleaner that can reliably protect an electric blower.
[0007]
[Means for Solving the Problems]
The present invention includes control means for controlling the voltage of a power supply to make the current value of an electric blower constant by controlling the voltage of a power supply, and for controlling the electric current of the electric blower to be equal to or less than a predetermined value when the on-duty of the electric blower becomes equal to or less than a predetermined value. It is. And, since the state of the electric blower is detected by the on-duty of the electric blower, the state of the electric blower can be reliably detected even when the electric current value of the electric blower is kept constant. The blower can be reliably protected.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the configuration of the first embodiment of the vacuum cleaner of the present invention will be described with reference to the drawings.
[0009]
In FIG. 2, reference numeral 1 denotes a cleaner main body, and the cleaner main body 1 collects dust sucked together with intake air generated by driving an electric blower 2 housed therein by a detachable dust collection pack (not shown). It is a dusty vacuum cleaner.
[0010]
The cleaner body 1 has a body suction port 7 for sucking air from the outside. The main body suction port 7 is connected to a bendable and substantially cylindrical hose body 11 that can be bent. At the tip of the hose body 11, a hand operation unit 12 that can select an operation mode of the electric blower 2 and the like is provided. The manual operation unit 12 is provided with a plurality of setting buttons 13 for setting the driving state of the electric blower 2 and the like in the cleaner main body 1 to a predetermined state, for example, each state of weak, medium, strong and off. At the same time, a gripping portion 14 that is gripped by an operator when cleaning is protruded toward the base end side.
[0011]
Further, an elongate and contractible elongated substantially cylindrical extension tube 15 is detachably connected to the distal end of the hand operation unit 12 in a detachable manner. Further, a floor brush 16 that is installed on, for example, a carpet on the floor in a room and sucks dust on the carpet is detachably connected to the tip of the extension tube 15 in a detachable manner.
[0012]
Next, the internal structure of the vacuum cleaner according to the first embodiment will be described with reference to FIG.
[0013]
In the cleaner body 1, the electric blower 2 is electrically connected in series to a commercial AC power supply E as a power supply via a fuse 21 as a cutoff means. As the fuse 21, a fuse having a fusing current smaller than a current value when the electric blower 2 is driven to the maximum is selected. Further, the electric blower 2 is electrically connected with a current detecting means 22 in series. Further, a triac 23 which is a bidirectional power control element as a current control means is electrically connected to the current detection means 22 in series. The triac 23 is connected to a commercial AC power supply E. A closed circuit is formed by the commercial AC power supply E, the electric blower 2, the current detecting means 22, and the triac 23.
[0014]
A control means 24 for controlling the driving state of the electric blower 2 is electrically connected in parallel between the current detection means 22 and the gate of the triac 23. The setting button 13 of the manual operation unit 12 is electrically connected to the control unit 24. Further, the control means 24 controls the phase conduction angle by turning on and off the triac 23 by supplying a predetermined pulse voltage to the gate of the triac 23 in accordance with the operation of the setting button 13, and controls the electric blower from the commercial AC power source E. 2 is controlled.
[0015]
Then, the control means 24 detects the current value of the electric blower 2 by the current detection means 22 and outputs the detected current value and a constant current value which is a predetermined value set in advance according to each operation mode of the electric blower 2. Is compared, the on-duration time or ratio of the triac 23, that is, the on-duty is increased or decreased, and the current value of the electric blower 2 is kept constant.
[0016]
That is, the control means 24 is in a state where the electric blower 2 cannot be driven due to a foreign substance being caught or the like, that is, in a so-called locked state, the back electromotive force of the electric blower 2 disappears, and the electric blower 2 detected by the current detecting means 22 When the current value rises, for example, the on-duty of the electric blower 2 is sequentially reduced by the triac 23, and the voltage of the electric blower 2 is controlled in order to return the current value to a constant value.
[0017]
When the current value of the electric blower 2 detected by the current detecting means 22 decreases due to accumulation of dust or the like, the control means 24 sequentially increases the on-duty of the electric blower 2 by the triac 23, and Are controlled so as to return the current value to a constant value by sequentially increasing the voltage.
[0018]
Next, the operation of the first embodiment will be described with reference to the flowchart shown in FIG.
[0019]
First, the control unit 24 detects which operation mode of the electric blower 2 is selected by the setting button 13 of the hand operation unit 12.
[0020]
The control means 24 detects whether the electric blower 2 is stopped by the setting button 13, that is, whether or not the cutoff mode is selected (step 1).
[0021]
In this step 1, when the control means 24 determines that the off mode is selected, the electric blower 2 is stopped (step 2), and the process returns to step 1.
[0022]
On the other hand, in step 1, when the control means 24 determines that the off mode has not been selected, it is determined whether the setting button 13 drives the electric blower 2 most strongly, that is, whether the strong mode has been selected. Detect (Step 3).
[0023]
In this step 3, when the control means 24 determines that the strong mode of the electric blower 2 is selected, the control means 24 controls the phase conduction angle by the triac 23 so that the electric blower The input voltage to the blower 2 is duty-controlled to control the current value of the electric blower 2 to be a constant current of, for example, 9 A (step 4). At this time, when the load on the electric blower 2 increases and the current of the electric blower 2 increases, the on-duty is reduced by less than the normal on-duty of the strong mode of the electric blower 2, for example, 80%. The electric current of the electric blower 2 is suppressed to 9A.
[0024]
On the other hand, when the control unit 24 determines in step 3 that the strong mode of the electric blower 2 is not selected, the state in which the electric blower 2 is driven second most strongly by the setting button 13, that is, the middle mode is set. It is detected whether or not it has been selected (step 5).
[0025]
In this step 5, when the control means 24 determines that the middle mode of the electric blower 2 is selected, the control means 24 controls the phase conduction angle by the triac 23 so that the electric blower The input voltage to the blower 2 is duty-controlled to control the current value of the electric blower 2 to be a constant current of, for example, 6 A (step 6). At this time, similarly to step 4, when the load on the electric blower 2 increases and the current of the electric blower 2 increases, the on-duty is set to be smaller than the normal on-duty in the middle mode of the electric blower 2. Thus, the current of the electric blower 2 is suppressed to 6A.
[0026]
On the other hand, if the control unit 24 determines in step 5 that the middle mode of the electric blower 2 has not been selected, the state in which the electric blower 2 is driven the weakest by the setting button 13, that is, the weak mode is selected. Is detected (step 7).
[0027]
In this step 7, when the control means 24 determines that the weak mode of the electric blower 2 is selected, the control means 24 controls the phase conduction angle by the triac 23 so that the electric blower The input voltage to the blower 2 is duty-controlled to control the current value of the electric blower 2 to be a constant current of, for example, 3 A (step 8). At this time, similarly to Steps 4 and 6, when the load on the electric blower 2 increases and the current of the electric blower 2 increases, the on-duty is set lower than the normal on-duty in the weak mode of the electric blower 2. By reducing the size, the current of the electric blower 2 is suppressed to 3A.
[0028]
On the other hand, if the control unit 24 determines in step 7 that the weak mode of the electric blower 2 has not been selected, the process returns to step 1.
[0029]
Further, in step 4, when controlling the electric blower 2 to have a constant current of 9 A, whether the on-duty of the electric blower 2 is a first threshold value which is a predetermined value, for example, 60% or less. It is determined by the control means 24 whether it is (step 9).
[0030]
In step 9, when the control unit 24 determines that the on-duty of the electric blower 2 is 60% or less, and when the on-duty of 60% or less continues for a predetermined time or more, the electric blower 2 The control means 24 determines that the electric blower 2 in which the current value of the electric blower 2 has increased due to the disappearance of the back electromotive force is in an abnormal state, for example, a locked state, and sets the on-duty of the electric blower 2 to 100%, that is, full on. Then, the electric blower 2 is protected by blowing the fuse 21 and electrically opening the closed circuit (step 10), and the operation is terminated.
[0031]
On the other hand, if the control unit 24 determines in step 9 that the on-duty of the electric blower 2 is not less than 60%, the process returns to step 1.
[0032]
Further, in step 6, when controlling the electric blower 2 to have a constant current of 6 A, the on-duty of the electric blower 2 is a second threshold value, which is a predetermined value, for example, 50% or less. The control means 24 determines whether or not this is the case (step 11).
[0033]
In step 11, when the control unit 24 determines that the on-duty of the electric blower 2 is 50% or less, and when the on-duty of 50% or less continues for a predetermined time or more, the electric blower 2 The control means 24 determines that the electric blower 2 in which the current value of the electric blower 2 has increased due to the absence of the back electromotive force is in an abnormal state, for example, a locked state, and proceeds to step 10.
[0034]
On the other hand, when the control unit 24 determines in step 11 that the on-duty of the electric blower 2 is not 50% or less, the process returns to step 1.
[0035]
Then, in step 8, when controlling the electric blower 2 to have a constant current of 3 A, whether the on-duty of the electric blower 2 is a third threshold value which is a predetermined value, for example, 40% or less. It is determined by the control means 24 (step 12).
[0036]
In step 12, when the control unit 24 determines that the on-duty of the electric blower 2 is 40% or less, and when the on-duty of 40% or less continues for a predetermined time or more, the electric blower 2 The control means 24 determines that the electric blower 2 in which the current value of the electric blower 2 has increased due to the absence of the back electromotive force is in an abnormal state, for example, a locked state, and proceeds to step 10.
[0037]
On the other hand, if the control unit 24 determines in step 12 that the on-duty of the electric blower 2 is not 40% or less, the process returns to step 1.
[0038]
As described above, in the first embodiment, the state of the electric blower 2 is detected by the on-duty of the electric blower 2, and when the on-duty of the electric blower 2 becomes equal to or less than the predetermined threshold value, In order to blow the fuse 21 by fully turning on the duty of the blower 2 to blow the fuse 21 and reduce the current of the electric blower 2 to a predetermined value or less, the control means 24 reliably detects an abnormal state such as the lock of the electric blower 2 and closes the circuit. The electric blower 2 can be reliably protected by being electrically opened.
[0039]
When the load on the electric blower 2 is reduced due to the accumulation of dust, the control unit 24 increases the on-duty of the electric blower 2 to keep the current value constant. Since the control is performed in the opposite manner to the case described above, the control means 24 does not mistakenly recognize the case where the dust is accumulated and the case where the dust is locked.
[0040]
Furthermore, since the fuse 21 is blown when the on-duty of the electric blower 2 has become equal to or less than the predetermined threshold for a predetermined time, for example, when the current detection unit 22 erroneously detects the current value of the electric blower 2 or the like. Even when the on-duty of the electric blower 2 instantaneously falls below a predetermined threshold, the fuse 21 is not erroneously blown, and the reliability of detecting the state of the electric blower 2 is further improved. it can.
[0041]
In addition, since the electric blower 2 is controlled to have a constant current according to each operation mode, it is possible to save power as a whole of the vacuum cleaner.
[0042]
Next, a second embodiment of the vacuum cleaner of the present invention will be described with reference to the flowchart shown in FIG.
[0043]
The embodiment shown in FIG. 4 reduces the current of the electric blower 2 to a predetermined value or less when the on-duty of the electric blower 2 is equal to or less than a predetermined value in the embodiment shown in FIGS. It is.
[0044]
That is, the control of steps 1 to 8, steps 11 and 12 is the same as steps 1 to 8, steps 11 and 12 in the embodiment shown in FIGS. In step 12, when the control means 24 determines that the on-duty of the electric blower 2 is 60%, 50%, and 40% or less, respectively, instead of step 10, the electric current of the electric blower 2 is set to a predetermined value. It is reduced below (step 21) and the process returns to step 1.
[0045]
Also in this case, similarly to the first embodiment, the state of the electric blower 2 is detected by the on-duty of the electric blower 2, and when the on-duty of the electric blower 2 becomes equal to or less than a predetermined threshold, the control unit 24 is activated. In order to reduce the electric current of the electric blower 2 to a predetermined value or less, the control means 24 reliably detects an abnormal state such as the lock of the electric blower 2 and electrically opens the closed circuit to reliably protect the electric blower 2. it can.
[0046]
Further, since there is no need to provide a fuse 21 or the like for electrically opening a closed circuit, there is no need to consider a case where the fuse 21 is not blown due to a defect or the like, so that the electric blower 2 can be reliably protected and a configuration of the vacuum cleaner Can be further simplified and manufacturability can be improved.
[0047]
Next, a third embodiment of the vacuum cleaner of the present invention will be described with reference to a flowchart shown in FIG.
[0048]
In the embodiment shown in FIG. 5, the application of voltage to the electric blower 2 is stopped when the fuse 21 does not blow in the embodiment shown in FIGS.
[0049]
That is, control of steps 1 to 9, steps 11 and 12 similar to steps 1 to 9, steps 11 and 12 in the embodiment shown in FIGS. 1 to 3 is performed, and instead of step 10, The electric blower 2 is fully turned on, that is, the on-duty of the electric blower 2 is set to 100% (step 31).
[0050]
Then, in a state where the electric blower 2 is fully turned on, the control unit 24 determines whether or not the fuse 21 has blown after a predetermined condition such as, for example, a predetermined time elapse (step 32).
[0051]
If the control means 24 determines in this step 32 that the fuse 21 has blown, the operation is terminated.
[0052]
On the other hand, when the control means 24 determines in step 32 that the fuse 21 is not blown, the control means 24 stops the application of the voltage to the electric blower 2 (step 33) and ends the operation. .
[0053]
Therefore, according to the third embodiment, after the operation mode of the electric blower 2 is determined by the control unit 24, the state of the electric blower 2 is changed by the on-duty threshold set in advance according to each operation mode. By detecting and performing the same control as in the first embodiment, such as by blowing the fuse 21 when the electric blower 2 is in an abnormal state, the same operation and effect as in the first embodiment can be obtained. .
[0054]
Further, for example, when the fuse 21 having a predetermined blowing current is not mixed at the time of manufacturing the vacuum cleaner, or when the fuse 21 itself is defective, even when the on-duty is set to 100%, the fuse 21 does not blow. However, by stopping the application of the voltage from the commercial AC power supply E to the electric blower 2 by the control means 24, the electric blower 2 can be double protected together with the fuse 21.
[0055]
In the third embodiment, step 32 is omitted, and regardless of whether the fuse 21 is blown or not, after the step 31, after a predetermined condition, for example, a predetermined time has elapsed, the electric blower 2 It is also possible to control so that the application of the voltage is always stopped. In this case, the control by the control means 24 can be further simplified.
[0056]
Further, in each of the above embodiments, as shown in FIG. 6, a secondary battery B as a power supply is provided in the cleaner main body 1 instead of the commercial AC power supply E, and the Alternatively, a drive circuit 25 as current control means may be provided in a closed circuit. In this case, by controlling the electric blower 2 at a constant current, the electric power of the vacuum cleaner can be reduced, so that the usable time of the secondary battery B, that is, the battery life can be extended.
[0057]
Further, the power supply and the current control means can arbitrarily combine the commercial AC power supply E, the secondary battery B, the triac 23, and the drive circuit 25, respectively. A configuration using a circuit other than the circuit 25 is also possible.
[0058]
Furthermore, the current value of the electric blower 2 and the threshold value of the on-duty in each of the low, medium, and strong operation modes can be arbitrarily set.
[0059]
The operation mode of the electric blower 2 is not limited to the above-described four stages of off, weak, medium, and strong, but may be more stages, or may be only on and off.
[0060]
In addition, other than the fuse 21, any other element such as a PTC (Positive Temperature Coefficient) element can be used as long as it can open a closed circuit by increasing the current.
[0061]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, since the state of an electric blower is detected by the on-duty of an electric blower, even if the electric current value of an electric blower is made constant, the state of an electric blower can be detected reliably and an electric blower can be protected reliably. .
[Brief description of the drawings]
FIG. 1 is a block diagram showing a first embodiment of a vacuum cleaner according to the present invention.
FIG. 2 is a perspective view showing the electric vacuum cleaner.
FIG. 3 is a flowchart showing control by a control unit of the electric vacuum cleaner.
FIG. 4 is a flowchart showing control by a control unit of the second embodiment of the vacuum cleaner of the present invention.
FIG. 5 is a flowchart showing control by a control unit of a third embodiment of the vacuum cleaner of the present invention.
FIG. 6 is a block diagram showing another embodiment of the vacuum cleaner of the present invention.
[Explanation of symbols]
2 Electric blower
24 Control means B Secondary battery E as a power source Commercial AC power source as a power source

Claims (4)

Electric blower,
Control means for making the current value of the electric blower constant by controlling the voltage of the power supply to make the current value of the electric blower constant, and for reducing the current of the electric blower to a predetermined value or less when the on-duty of the electric blower becomes a predetermined value or less. Vacuum cleaner characterized by. When the on-duty of the electric blower is equal to or less than a predetermined value, the control means increases the current of the electric blower to electrically open a closed circuit between the electric blower and the power supply, thereby reducing the electric current of the electric blower to a predetermined value or less. 2. The vacuum cleaner according to claim 1, wherein: The control means increases the current of the electric blower and stops application of the voltage from the power supply to the electric blower when the closed circuit between the electric blower and the power supply is not electrically opened after a predetermined condition. An electric vacuum cleaner according to claim 2. The vacuum cleaner according to any one of claims 1 to 3, wherein the power source is a battery.

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