JPH08164100A - Vacuum cleaner - Google Patents

Abstract

PURPOSE: To protect a motor from an excess current and to improve operability. CONSTITUTION: When a current value of a motor is equal to 1A or larger and less than 2A, it is measured by counter circuits 71 and 72. When the current value is continuously equal to such a value for two seconds or more, the current which is applied to the motor is cut off by a mono-multi vibrator circuit 75 and the motor is stopped. When the current value of the motor is equal to 2A or larger, it is measured by a counter circuit 73. When the current of such a value continues for 40m/sec or more, the current supplied to the motor is cut off by the mono-multi vibrator circuit 75, thereby stopping the motor. In case of a relatively small excessive current in a range from 1A to less than 2A, the operation of the motor is continued for a relatively long time. In case of an excess current of a large current of 2A or larger, the motor is shortly stopped. In the case where the value is in a range from 1A to less than 2A, when moving direction detecting means 46 detects a reverse rotation, the counter circuits 71 and 72 are reset. When the value is 2A or larger, the counter circuit 73 is reset when the motor is activated. Thus, the motor is certainly protected from the excess current and the reduction of the operability is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vacuum cleaner having a suction body having a rotating body rotated by an electric motor.

[0002]

2. Description of the Related Art Heretofore, as a vacuum cleaner of this type, a structure described in, for example, JP-A-5-146387 has been known.

The electric vacuum cleaner disclosed in Japanese Unexamined Patent Publication No. 5-146387 has a rotary body such as a cleaning blade in the suction port body, and the rotary body is rotationally driven by an electric motor. Further, when an overcurrent of a predetermined set value or more, which is larger than the current flowing through the electric motor, flows through the electric motor during normal cleaning, the electric power supplied to the electric motor is reduced, and when this state continues for a predetermined time or longer, the electric motor is The electric power supplied to is stopped and the electric motor is stopped. In this way, it is possible to prevent foreign matter from getting into the rotating body, heating of the electric motor, heating of electronic parts, scratches on the floor, and the like, and to prevent deterioration of operability due to frequent stop of the electric motor. .

[0004]

However, in a rare short-circuit state in which foreign matter is entangled in the rotating body or the coils of the electric motor are short-circuited, it is necessary to immediately interrupt the current to stop the electric motor. On the other hand, when the current is increased due to the load being increased by pressing the main body of the suction port against the carpet, the life of the motor will be greatly reduced without decreasing the power supplied to the motor within a predetermined time. However, when the power is reduced, the operability is rather deteriorated.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electric vacuum cleaner which can both protect the electric vacuum cleaner and improve operability.

[0006]

The electric vacuum cleaner of the present invention comprises:
A suction port main body, and a rotating body provided in the suction port main body,
An electric motor that rotates the rotating body and a control unit that controls the electric motor are provided, and the control unit includes a moving direction detecting unit that detects a moving direction of the suction port body, and a relatively small first set current. Value and a second set current value larger than the first set current value, and an overcurrent detection for detecting an overcurrent state in which the current value supplied to the electric motor exceeds each set current value. Means, a first set time for determining an overcurrent state corresponding to the first set current value set by the overcurrent detection means, and a second set time shorter than the first set time. A second setting time for judging an overcurrent state corresponding to the set current value, and a measuring means for measuring the state of the overcurrent when the overcurrent exceeding the respective set values flows in the overcurrent detection means; First setting by overcurrent detection means When the moving direction detecting means detects a reversal in a state in which an overcurrent state corresponding to the current value is detected, the measurement of this overcurrent state is reset, and when the electric motor is started, the second set current value of the measuring means is set. It is provided with a reset means for resetting the measurement of the corresponding overcurrent state, and a stop means for shutting off the current supplied to the electric motor when the measuring means measures any one of the set times.

[0007]

In the electric vacuum cleaner of the present invention, when the current value of the electric motor detected by the overcurrent detecting means exceeds the first set current value,
The time when the first set current value is exceeded is measured by the measuring means, and when the set time corresponding to the first set current value is exceeded, the current supplied to the electric motor is cut off and the electric motor is stopped. When the current value of the electric motor detected by the overcurrent detection means exceeds the second set current value, the measuring means measures the time in the state of exceeding the second set value, and the second set value is set. When the corresponding comparatively short set time is exceeded, the electric current supplied to the electric motor is cut off to stop the electric motor. Therefore, in the case of the first set current value, the electric motor operation is continued for a relatively long time and the second set value is set. In the case of the current value, the electric motor is stopped in a relatively short time, and the electric motor is protected from overcurrent without lowering operability. Further, in the case of the first set current value, when the rotation direction of the suction port body is detected to be reversed by the moving direction detection means, the measuring means is reset, and in the case of the second set current value, the measurement is performed at the time of starting the electric motor. Since the means is reset, the electric motor can be surely protected from an overcurrent and the operability is prevented from being deteriorated.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an embodiment of the vacuum cleaner of the present invention will be described below with reference to the drawings.

In FIG. 3, reference numeral 1 denotes an electric vacuum cleaner body. A base end of a hose 2 is detachably connected to the electric vacuum cleaner body 1, and a tip of the hose 2 is branched rearward. A hand operation unit 3 having a shape is provided. A suction port body 5 is attached to the distal end of the hand operation unit 3 via a stretchable extension tube 4.

As shown in FIG. 4, the suction port main body 5 has a suction chamber 11 defined in the front and the left in a substantially left-right direction. Inside the suction chamber 11, a cleaning blade, which is a cleaning body as a rotating body, is formed. A cleaning blade 12 is rotatably supported, and a pulley 13 is formed at one end of the cleaning blade 12.

On the other hand, at the rear end side, there is a motor storage chamber 14
Is formed, the electric motor 15 is housed, and the drive shaft of the electric motor 15 is formed.
A drive pulley 17 is provided at 16, a drive belt 19 is stretched between the pulley 13 of the cleaning blade 12 and the drive pulley 17, and the cleaning blade 12 is rotated by the electric motor 15.

Further, a connecting pipe is provided substantially at the center of the suction port body 5.
20 is rotatably provided in the vertical direction, and the vacuum cleaner body 1 is provided via the suction chamber 11, the extension pipe 4 and the hose 2.
A communication passage 21 that communicates with is formed.

On the other hand, a control unit storage chamber 22 is formed at the other end on the rear side, and a plurality of circuit boards 23 are formed in the control unit storage chamber 22.
Is provided.

A rotation direction detecting section 24 for detecting the traveling direction is provided in the control section accommodating chamber 22. As shown in FIG. 5, the rotation direction detecting unit 24 is a rotation roller that is rotated in a direction following the advancing direction of the suction port body 5 by coming into contact with the floor surface inside a switch case body 25 having an open lower surface. 26
Reflecting rollers 28a and 28b serving as rotating members are mounted coaxially with the rotating shaft 27 of the rotating roller 26, and the case cover body 29 for preventing dust from entering the lower surface of the reflecting rollers 28a and 28b has a screw 30. It is installed in. As shown in FIG. 6, the reflecting rollers 28a and 28b are formed with reflecting surfaces 28a1 and 28b1 and non-reflecting surfaces 28a2 and 28b2, which are different from each other by 90 °, over 180 °.

Further, photosensors 31a and 31b, which are non-contact type sensors, are attached to the switch case body 25 so as to face the reflection rollers 28a and 28b with a gap therebetween.

Next, an electric circuit will be described with reference to FIGS. 1 and 2.

First, as shown in FIG. 2, a frequency of 50 Hz
The AC input terminal of the full-wave rectifier circuit 41 is connected to the commercial AC power source E, and the diode D1, the resistor R1, and the zener diode ZD for constant voltage are connected between the output terminals of the full-wave rectifier circuit 41.
1 is connected, the smoothing capacitor C1 is connected in parallel to the Zener diode ZD1, and the Zener diode ZD1
The connection terminal of the capacitor C1 and the constant voltage source Vcc.

Further, between the diode D1 and the resistor R1,
A transistor Q1, a field effect transistor Q2, and a current detection resistor R2 are connected in series, and a series circuit of a transistor Q3 and a field effect transistor Q4 is connected in parallel to the transistor Q1 and the field effect transistor Q2. And transistor Q1, field effect transistor Q2, transistor Q3 and field effect transistor
The switching means 43 is constituted by Q4.

Further, the emitter and collector of the transistor Q5 and the resistor R3 are connected between the base and the emitter of the transistor Q1, and the base of the transistor Q5 is a resistor.
It is connected to the connection point of the diode D1 and the resistor R1 via R4, and is also connected to the connection point of the transistor Q3 and the field effect transistor Q4 via the resistor R5. The emitter and collector of the transistor Q6 and the resistor R6 are connected between the base and the emitter of the transistor Q3, and the base of the transistor Q6 is connected to the connection point of the diode D1 and the resistor R1 via the resistor R7.
It is connected to the connection point of the transistor Q1 and the field effect transistor Q2 via the resistor R8.

A series circuit of resistors R11 and R12 is connected between the output terminals of the full-wave rectification circuit 41, and an inverter circuit 42 is connected to the connection point of the resistors R11 and R12. 42 output terminals are 1
A clock terminal CK that outputs a clock every 0 ms is configured.

On the other hand, in the control means 44, the photo sensor 31a is connected to the clock terminal of the D-flip-flop circuit 45 for detecting the traveling direction, and the photo sensor 31b is connected to the data input terminal of the D-flip-flop circuit 45. The non-inverting output terminal Q and the inverting output terminal Q are connected to the moving direction detecting means 46, respectively. The moving direction detecting means 46 has flip-flop circuits 47, 48, 49 and 50,
The AND circuit is connected to the gate of the field effect transistor Q2 via the AND circuit 51 and the AND circuit 52, and
Field effect transistor Q4 via 53 and AND circuit 54
Connected to the gate. Further, the photo sensor 31b is connected to the mono multivibrator circuit 55 for maintaining operation, and the connection point of the resistor R15 and the capacitor C2 connected between the constant voltage source Vcc and the ground is connected to the mono multivibrator circuit 55. The output terminal Q of the mono-multivibrator circuit 55 is an AND circuit 52 and an AND circuit.
Connected to 54. In addition, each of the non-inverting input terminal Q and the inverting input terminal Q of the D-flip-flop circuit 45 is
Flip-flop circuits 47 and 48 and flip-flop circuits 49 and 50 are connected in two stages, and photosensors 31a and 31b are connected.
Corresponds to the inversion from.

Further, the control means 44 has an overcurrent detection means 61, and this overcurrent detection means 61 sets a first set current value of an overcurrent of 1 A which is a relatively small current value, for example. The series circuit connected between the constant voltage source Vcc of the resistor R16 and the resistor R17 and the ground, and the resistor R18 that sets the overcurrent setting current value of 2.5A, which is a larger current value.
And a series circuit connected between the constant voltage source Vcc of the resistor R19 and ground.

The connection point of the resistors R16 and R17 is connected to the inverting input terminal of the operational amplifier 62, the non-inverting input terminal of the operational amplifier 62 is connected to the current detecting resistor R2, and the output terminal is connected to the resistor R21. It is connected to the constant voltage source Vcc through and to the input terminal of the mono-multivibrator circuit 63. The connection point of the resistors R18 and R19 is connected to the inverting input terminal of the operational amplifier 64, and the non-inverting input terminal of the operational amplifier 64 is connected to the resistor R2 for current detection.
The output terminal is connected to the constant voltage source Vcc through the resistor R22.
And to the input terminal of the mono-multivibrator circuit 65. Further, the input terminal of the mono-multivibrator circuit 63 has a resistor R23 connected between a constant voltage source Vcc and a ground for setting a time of, for example, 1.5 ms for stabilizing operation, and a resistor R23 and a capacitor in a series circuit of a capacitor C3. The connection point of C3 is connected, and similarly, to the input terminal of the mono multivibrator circuit 65,
A connection point of a resistor R24 and a capacitor C4 in a series circuit of a resistor R24 and a capacitor C4 connected between a constant voltage source Vcc for setting a time of 1.5 ms for stabilizing operation and a ground is connected.

The reset terminal of the mono-multivibrator circuit 63 is connected to the output terminals of the AND circuit 51 and the AND circuit 53 via an OR circuit 66 as a reset means, and the reset terminal of the mono-multivibrator circuit 65 is A reset component 67 as reset means for detecting the start-up of the electric motor 15 is connected.

Further, the measuring means 70 is connected to the output terminals of the mono-multivibrator circuit 63 and the mono-multivibrator circuit 65, and the measuring means 70 has a relatively long 200 clock corresponding to an overcurrent having a relatively small current value. , Two counter circuits 71 for setting the set time of about 2 seconds,
72 and a counter circuit 73 for setting a set time of about 40 ms which is four clocks corresponding to an overcurrent having a larger current value 73
And a counter circuit 72 and a counter circuit 73.
Is connected to an OR circuit 74, the output terminal of the OR circuit 74 is connected to the input terminal of a mono-multivibrator circuit 75 as a stopping means, and the inverting output terminal Q of the mono-multivibrator circuit 75 is an AND circuit 52 and an AND circuit 54. Is connected to the input terminal of.

Next, the operation of the above embodiment will be described.

First, as shown in FIG. 7, the moving direction detecting means 46 has a suction port body 5 when the output of the photo sensor 31a falls from the H level to the L level while the photo sensor 31b is at the H level. Is moving forward, and the output F1 is output from the AND circuit 52, and the photo sensor
The output of the photo sensor 31a is at H level when 31b is at L level.
When it falls from the level to the L level, it is detected that the suction port body 5 is retracted, and the AND circuit 54 outputs the output F2.

When the field effect transistor Q2 and the field effect transistor Q4 are turned on at the same time, a series circuit of the transistor Q1 and the field effect transistor Q2 and a series circuit of the transistor Q3 and the field effect transistor Q4 are formed and short-circuited. Since a current flows, the field effect transistor Q2 or the field effect transistor Q4 is turned off, and then the flip-flop circuits 47, 48, 49, 50 and the AND circuits 51, 52 are used to set the buffer time respectively. Turn on Q4 or field effect transistor Q2.

Then, when the power is turned on, the AC voltage of the commercial AC power source E is full-wave rectified by the full-wave rectifier circuit 41, a constant voltage is set by the Zener diode ZD1, and smoothed by the capacitor C1. A constant DC voltage is applied between Q1 and field effect transistor Q2, and between transistor Q3 and field effect transistor Q4.

Photosensor 31a and photosensor 31b
Based on the output of the above, the moving direction detecting means 46 detects that the moving direction of the suction port main body 5 is the forward direction, and the non-inverted output of the mono-multivibrator circuit 55 for 1 second after the last output from the photo sensor 31b. When the H level output is made from the terminal and the current value flowing through the electric motor 15 is the current value at the normal time, that is, less than 1 A, the mono-multivibrator circuit
The output from the inverting output terminal of 75 becomes H level, and the output is made from the AND circuit 52.

When an output is made from the AND circuit 52, a voltage is applied to the gate of the field effect transistor Q2 to turn on the field effect transistor Q2 and a current is supplied to the base of the transistor Q3 to turn on the transistor Q3. , The transistor Q3 and the field effect transistor Q2 are turned on, a forward current flows to the motor 15,
15 turns forward. In this state, the cleaning blade 12 rotates forward in the traveling direction of the suction port body 5 to scrape up the dust.

On the other hand, on the basis of the outputs of the photosensors 31a and 31b, the moving direction detecting means 46 detects that the moving direction of the suction port body 5 has been reversed to the backward direction, and the output from the photosensor 31b is used to detect the mono-multi. An H level output is made from the non-inverting output terminal of the vibrator circuit 55,
The current value flowing in the electric motor 15 is the normal current value, that is, 1
When it is less than A, the output from the inverting output terminal of the mono-multivibrator circuit 75 becomes H level, and the AND circuit 54 outputs it.

When an output is made from the AND circuit 54, a voltage is applied to the gate of the field effect transistor Q4 to turn on the field effect transistor Q4 and a current is supplied to the base of the transistor Q1 to turn on the transistor Q1. , Transistor Q1 and field effect transistor Q4 turn on, causing a reverse current to flow in motor 15,
15 reverses. In this state, the cleaning blade 12 reversely rotates in the traveling direction of the suction port body 5 to scrape up dust.

Further, for example, the suction port body 5 is pressed against the floor surface such as a carpet or a plate, and the electric motor 15
The rotation speed of the motor decreases, the back electromotive force of the motor 15 decreases, and a relatively small overcurrent of 1 A or more and less than 2 A flows in the motor 15 to increase the current value flowing in the resistor R2.
When it exceeds the set value set by R16 and resistor R17,
The operational amplifier 62 outputs the H level and is input to the mono multivibrator circuit 63.

Then, the counter circuit 71 and the counter circuit 72 measure 200 counts, for example, 2 seconds, and when the load current is 1 A or more and less than 2 A for 2 seconds or more, the inverting output terminal of the mono-multivibrator circuit 75 outputs L level. Then, the AND circuit 52 and the AND circuit 54 are input, the output of each of the AND circuit 52 and the AND circuit 54 becomes L level, and the voltage is applied to both the gates of the field effect transistor Q2 and the field effect transistor Q4. First, the electric motor 15 is stopped. Therefore, deterioration of the electric motor 15 and excessive heating of electronic components are prevented.

When the moving direction detecting means 46 determines that the moving direction of the suction port body 5 is reversed with the load current being 1 A or more, the OR circuit 66 resets the mono-multivibrator circuit 63, The counter circuits 71 and 72 reset the count and start counting from 1. Therefore, since the count is reset each time the moving direction is reversed, it is possible to prevent the electric motor 15 from frequently stopping, and to stop the electric motor 15 unnecessarily even if the suction port body 5 is pressed against a carpet or the like for cleaning. Operation is improved, and because of the relatively small overcurrent,
The short-time energization is unlikely to cause deterioration of the electric motor 15 or excessive heating of electronic components.

On the other hand, for example, when the electric motor 15 is rarely short-circuited or the cleaning blade 12 is entangled with a foreign substance, the electric motor 15
A large overcurrent with a load current of 2 A or more flowing through 15 causes the current value flowing through resistor R2 to rise, causing resistance R18 and resistor R1
When the value exceeds the set value set in 9, the operational amplifier 64 also outputs the H level together with the operational amplifier 62 and is input to the mono-multivibrator circuit 65.

Then, the counter circuit 73 measures 4 counts, for example, 40 ms, and the load current is 2 for 40 ms or more.
When it is A or more, the inverting output terminal of the mono-multivibrator circuit 75 outputs L level and inputs it to the AND circuit 52 and AND circuit 54, and the output of any AND circuit 52 and AND circuit 54 becomes L level. No voltage is applied to the gates of the field effect transistor Q2 and the field effect transistor Q4, and the electric motor 15 is stopped. Therefore, when a large overcurrent occurs, the motor 15
The supply of electric current to the motor 15 is stopped to prevent deterioration of the electric motor 15 and excessive heating of electronic components.

Further, when the load current is 2 A or more, some relatively large abnormality, for example, a rare short circuit of the electric motor 15 or foreign matter entangled in the cleaning blade 12, is considered. Therefore, the counter is kept until the electric motor 15 is restarted. Without resetting the circuit 73, the counter circuit 73 resets the count by starting the motor 15 and starts counting from 1. Therefore, since the state where the load current is large is not maintained, deterioration of the electric motor 15 and excessive heating of electronic components are unlikely to occur.

That is, when the electric motor 15 is rarely short-circuited, it usually takes about 1 second until the fuse (not shown) is blown, and during this time, a large current flows through each circuit component, causing deterioration or destruction of these circuit components or electrical failure. Vacuum cleaner body 1
However, the current supplied to the electric motor 15 can be immediately stopped in 40 msec.
It is possible to prevent the destruction, the heating of other electronic parts, and the destruction.

In this way, protection of the electric vacuum cleaner, that is, suppression of deterioration of parts, while improving operability,
It is possible to prolong the service life of parts and reduce the number of replacement parts by preventing the failure of other parts when some parts fail.

The electronic parts for control are generally 4-5.
Even if the current value of A is 100 msec or less, deterioration and damage can be prevented, so even if a current of 2 A flows, the current is cut off in 40 msec, so it is within the safe operation area of electronic parts, which is a safety problem. Absent.

As described above, in the present embodiment, when a relatively large abnormality such as a state where the cleaning blade 12 as a rotating body is contaminated with foreign matter and the electric motor 15 is locked, the electric current supplied to the electric motor 15 is immediately stopped. 15 can be protected. Further, since the first set time, which is a relatively small overcurrent state, is set longer than the second set time, which is a large overcurrent state, the electric motor 15 is carelessly pressed when the suction port body is temporarily pressed against the floor surface. Since it does not stop, operability can be improved.

Moreover, since the first set time is reset when the moving direction of the suction port body 5 is reversed,
By shortening the first set time, the elements, the electric motor 15, etc. can be protected more reliably. That is, even if the first set time is shortened, the electric motor 15 will not be inadvertently stopped if the suction port body 5 is reversed during cleaning.

In the above embodiment, the electric vacuum cleaner having the function of detecting the advancing direction of the suction port body 5 and reversing the electric motor 15 according to the advancing direction has been described.
It can also be applied to an electric vacuum cleaner provided with only the cleaning blade 12 having no such inversion function.

The frequency of the commercial AC power source E is 50 Hz.
However, 60 Hz can also be supported. In this case, the clock pulse has a frequency of 120 Hz and the clock is output every 8 ms, so that the set times until the stop are 1.7 seconds and 32 ms, respectively.

[0047]

According to the electric vacuum cleaner of the present invention, when the electric current value of the electric motor detected by the overcurrent detecting means exceeds the first set current value, the state of exceeding the first set current value is maintained. The time is measured by the measuring means, and when the set time corresponding to the first set current value is exceeded, the current supplied to the electric motor is cut off to stop the electric motor, and the electric current of the electric motor detected by the overcurrent detecting means is detected. When the value exceeds the second set current value, the time in the state of exceeding the second set value is measured by the measuring means, and when the relatively short set time corresponding to the second set value is exceeded,
Since the electric current supplied to the electric motor is shut off to stop the electric motor, the operation of the electric motor is continued for a relatively long time in the case of the first set current value, and the electric motor is stopped in a comparatively short time in the case of the second set current value. To protect the motor from overcurrent without reducing operability. Further, in the case of the first set current value, when the rotation direction of the suction port body is detected to be reversed by the moving direction detection means, the measuring means is reset, and in the case of the second set current value, the measurement is performed at the time of starting the electric motor. Since the means is reset, it is possible to reliably protect the electric motor from overcurrent, prevent deterioration in operability, and achieve both protection and improvement in operability.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a control means of an embodiment of an electric vacuum cleaner of the present invention.

FIG. 2 is a circuit diagram showing a circuit for driving the same electric motor.

FIG. 3 is a perspective view showing the same electric vacuum cleaner.

FIG. 4 is a perspective view showing a part of the suction inlet main body of the same.

FIG. 5 is an exploded perspective view showing the upper direction detecting means.

FIG. 6 is a cross-sectional view showing the same roller.

FIG. 7 is a timing chart showing the operation of the upward direction detecting means.

[Explanation of symbols]

 5 Suction port body 12 Cleaning blade as a rotating body 15 Electric motor 44 Control means 46 Moving direction detecting means 61 Overcurrent detecting means 66 OR circuit as resetting means 67 Reset component as resetting means 70 Measuring means 75 Mono-multi as stopping means Vibrator circuit

Claims (1)

[Claims] 1. A suction port body, a rotating body provided in the suction port body, an electric motor for rotating the rotating body, and control means for controlling the electric motor, wherein the control means includes the suction means. The moving direction detecting means for detecting the moving direction of the mouth body, a relatively small first set current value, and a second set current value larger than the first set current value are supplied to the electric motor. Overcurrent detecting means for detecting an overcurrent state in which the current value exceeds the set current value, and an overcurrent state corresponding to the first set current value set by the overcurrent detection means. 1 set time, and
There is a second set time which is set to a time shorter than the first set time and which judges an overcurrent state corresponding to a second set current value, and the overcurrent which exceeds each set value by the overcurrent detection means. When the reverse direction is detected by the moving direction detecting means while the overcurrent state corresponding to the first set current value is detected by the overcurrent detecting means, Resetting means for resetting the measurement of the current state and resetting the measurement of the overcurrent state corresponding to the second set current value of the measuring means when the electric motor is started; and the measuring means for measuring any one of the set times. Then, the electric vacuum cleaner comprising: a stopping unit that interrupts a current supplied to the electric motor.