JPS6040030A - Electric cleaner - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Technical field of invention The present invention relates to a vacuum cleaner.

TECHNICAL BACKGROUND OF THE INVENTION FIG. 1 shows the external appearance of a conventional vacuum cleaner. In front of the main body case 1, there is a dust collection case 3 that can be attached and detached using a clamp 2.
The cover 4 of the main body case 1 is provided with an operation section 5 and a display section 6. FIG. 2 shows the circuit configuration. Basically, an electric blower 8 and a bidirectional thyristor 9 forming a control circuit are connected in series to an AC power supply 7 of AC 50/60 Hz lOOV. A timer circuit 10 is connected to the gate of the bidirectional thyristor 9. This timer circuit 1o includes a resistor R27,
It mainly includes an integrating circuit including R28, a capacitor C19, a comparator amplifier IC24, and a bidirectional thyreiter 11, and also includes resistors R:n, R32, and resistors R29, R30, and VR4 that form a voltage generation circuit. It is configured. Here, an input from the variable resistor V R1, which is varied by operating the operating section 5, is applied to the resistor R2i. A DC power supply is supplied to such a timer circuit 10, and therefore a remote control circuit is connected to the AC power supply 7.

That is, 15V due to Zener diode Z D 12
The 7.5V line is secured by the Zener diode ZD12, and the resistor Rt2
- Rt9, diode Du, capacitor C12-C
17, transistor Trxt, unidirectional thyristor 5C
Rz and a hand switch 12. R12
is a current limiting resistor, R13 and R14 are electric shock prevention resistors,
R15 is a collector current limiting resistor, R1e is a gate protection resistor, RI7. Rte and R19 are bleeder resistances. A zero cross detection circuit 17 is connected to the timer circuit 10. The zero cross detection circuit mainly includes transistors T r 12 to T r 15, and includes resistors R221R23, R26, etc.

Here, the transistor T r lli is the capacitor C1
9 in parallel. In addition, voltage dividing resistors R22, R
23 is connected in parallel to the bidirectional thyristor 9.

In such a configuration, a setting signal for the variable resistor VR1 is input, and the potential at point A of the capacitor Css gradually increases due to the action of the integrating circuit. At this time, the comparator amplifier I
A reference voltage is set for C24 by resistors R29, VR4, and R2O, and when the potential at point A becomes higher than this reference voltage, the output of comparison amplifier IC24 becomes H level. As a result, a current flows to the gate of the bidirectional thyristor 11 in the previous stage, turning the bidirectional thyristor 11 ON, thereby gate-triggering the bidirectional thyristor 9 and turning it ON. Here, the setting value (reference voltage) of one terminal of the comparison amplifier IC 24 determines the minimum input of the electric blower 8. By increasing the input value, the slope of the integrating circuit is changed, and the conduction of the bidirectional thyristor 9 is changed. Control the input by changing the time. Next, the operation of the zero-cross detection circuit for such a timer circuit 10 will be explained. Now, in the positive direction of AC, the transistor T r 1z is ONt
,, the transistor T r 13 becomes OFF. therefore.

Transistors Tr1t and Trt5 are OFF. Then, at the moment when the alternating current changes from the positive direction to the negative direction and crosses zero potential, the transistor T r 12 is turned off and the transistor T r zs is turned on. Therefore, the electric charge stored in the capacitor C19 is transferred to this transistor T.
It is discharged by r 1!1, and the potential at point A drops to OV. After the zero potential cross, when the operating voltage is reached in the negative direction, the transistor Tr13. Tr1a is ONL, and the transistor T r ts is turned OFF.

As a result, the timer circuit 10 starts operating and charging of the capacitor C19 starts. Then, when the potential at point A reaches a predetermined voltage, the comparison amplifier IC24
, the bidirectional thyristor 9 is turned on by the action of the bidirectional thyristor 11. After that, at the moment when the alternating current changes from the negative direction to the positive direction and crosses zero potential, the transistor Tr13.
Tr14 is OFF and transistor Tr15 is ON
As a result, the charge in the capacitor C19 is discharged, and the potential at point A becomes Ov. Then, after the zero potential crosses, when the operating voltage is reached in the positive direction, the transistor T r 12 is turned on and the transistor T r 1s is turned off. Therefore, similar operations are repeated.

That is, when the AC zero potential crosses, the capacitor C19 is discharged and the timer circuit 10 does not operate, and at the operating voltage after the zero potential cross, the transistor Tr 12 or Tr 13 turns ON, and the transistor Tris turns OFF. As a result, the operation of the timer circuit 10, that is, charging of the capacitor Cus is started, and when the potential at point A reaches a predetermined value, the bidirectional thyriter 9 is turned on.

The operation part 5 is the output from the sensor (automatic) with the switch SW.
and the output from variable resistor VR1 (manual).

The sensor section 13 operates by detecting the magnitude of the air volume during dust collection with an operating body, for example, a flap, and converting the movement into an electrical signal, and is provided with a converting body. Here, a Hall element IC3 is used. That is, a magnet is placed on the flap side, and a Hall element IC3 is placed on the opposite fixed side to detect changes in the magnetic field.

Here, take out the output from the 2nd and 4th pins of the Hall element IC3.

A constant current is supplied by 1.3 bins. Further, the operational amplifier IC21 constitutes a constant current power source for driving the Hall element IC3 with a constant current. and.

Operational amplifiers IC22 and IC23 constitute a sensor signal amplifier, and the first stage IC22 performs differential amplification, and the next stage IC23 performs offset adjustment.

It performs gain adjustment, and the output is given to the sensor output terminal of the switch SW of the operation section 5. Here, the gain is set so that it decreases as the slider of the variable resistor VR3 moves toward the output side of the IC 23, and increases toward the ground. Further, the variable resistor VR2 for offset adjustment corrects variations in IC3.

Therefore, the display circuit 14 uses LED D as a light emitting element.
z, D2, D3, and D4 are connected in series, and is under a comparison voltage source made up of resistors R1 to R4.

Comparison amplifier ICI 1. ICI 2. ICI:H:,
, 4J lighting is controlled. Here, LED D, 1 is always lit and also serves as a pilot. Further, the comparator amplifiers IC11 to ICI3 are open collectors, and each switching causes the LEDs D1 to D4 to blink, and is connected to the connection point of each of the LEDs D1 to D4. FIG. 3 shows an isometric circuit near this display circuit 14, in which each comparison amplifier IC11 to
ICI 3 has transistors T r 1 to T r
3 and is an open collector. The second comparison voltage is set by the resistors Rx, R2, R3', and R4 using the 7.5V line as the power source.
When the comparison voltage becomes higher than the comparison voltage of
F, and the transistor Tr2. Since Tr3 remains ON, LEDs Dl and D2 are turned on. Then, when the signal output becomes higher than the comparison voltage of IC:12, the transistor T r 2 is also turned off, and the LED
Dl, Dz, and D3 will light up. Here, L
Power is supplied to the ED via resistors R7 and R11, and the resistor R6 is set to form a constant current circuit, so the brightness will vary regardless of the number of LEDs that should be lit. remains almost unchanged. Multiple L like this
With ED, the air volume is automatically displayed in proportion to the movement of the flap, and when it is manual, it is displayed in relation to the position of the variable resistor V Rt.

In other words, the display is proportional to the input control amount.

Problems with the Prior Art In such a conventional system, the terminal LEDD4 should be lit when all the transistors Trz~T3 are 0FFLL.
, Tr2 is 0FFL, , when the transistor Tr3 is ON, the ON voltage of this transistor Tr3 is 0.6~
When the voltage reaches about IV, a current also flows through the LED D4, so that the LED D4, which should not be lit when the ON voltage is large, also lights up brightly, resulting in an unclear 1 display state.

Purpose of the Invention The present invention has been made in view of the above points, and is capable of performing accurate display according to signal input in a display circuit that uses a plurality of light emitting elements connected in series. Aim to get a vacuum cleaner.

Summary of the Invention The present invention solves one problem by connecting a switching element controlled by the output of a voltage comparator that controls the light emitting element one light emitting element before the end of one light emitting element between the light emitting element at the end and the power supply. The lighting and turning off of the light-emitting element at the terminal end can be reliably controlled by turning ON and OFF the switching element, and an appropriate display can be made according to the signal input.

Examples of the invention An embodiment of the present invention will be described based on FIG. 4.

Components that are the same as those shown in FIGS. 1 to 3 are denoted by the same reference numerals, and description thereof will be omitted. In this example, the terminal LED D
A transistor Tr4 as a switching element is connected between 4 and the power supply (ground side), and this transistor Tr4 is built in the comparison amplifier IC14.

Here, this comparator amplifier ICI 4 is connected to the previous LED.
It has the opposite polarity to the comparison amplifier ICI 3 for D3 control, and I
When Cl3 is turned off, IC14 is turned on.

Therefore, if we look at the lighting states in order, the transistor Trz
~LED Dt lights up due to Tr3ON.

When transistors Trz to Tr3 are turned on, LED Dl,
D2 lights up and becomes L by turning on only transistor Tr3.
ED Dl, D2. D3 lights up. At these times, the transistor Tr4 remains in the OFF state, so the LE
No current flows through the DD4, and the non-lighting state is maintained. Then, when the signal input becomes equal to or higher than the comparison voltage of TC13, the transistor Tr3 is turned off, while the transistor Tr4 is turned on for the first time, and all of the LEDs Dl-D4 are turned on.

Effects of the Invention Since the present invention is configured as described above, even for the problematic light-emitting element at the end, the current can be set to 0 when it should not be lit by the switching element inserted between the power source and the light-emitting element at the terminal end to ensure that it is extinguished. It can be maintained in a lit state, and therefore, the display by the plurality of light emitting elements can be made accurate in accordance with the signal input.

[Brief Description of the Drawings] Fig. 1 is an external perspective view, Fig. 2 is a circuit diagram showing a conventional example, Fig. 3 is an equivalent circuit diagram of a part thereof, and Fig. 4 shows an embodiment of the present invention. It is an equivalent circuit diagram. 7... AC power supply, 8... Electric blower, 9... Bidirectional thyristor (control circuit), 14. Display circuit, D1 to D
, I...LED (light emitting element), ICII~T-C1
4...Voltage comparator, Tr4...Transistor (switching element) Applicant Tokyo Electric Co., Ltd.

Claims (1)

[Claims] An electric blower and a control circuit are connected in series to an AC power source, and multiple light emitting elements are connected in series to display an indication according to changes in the input voltage, air volume, or pressure of the electric blower, or changes in a variable resistor for manual adjustment. A display circuit is provided, and the output of a voltage comparator is connected to the connection point of these light emitting elements, and the output of the voltage comparator is controlled by the output of the voltage comparator that controls the light emitting element one position before the termination of the light emitting element. A vacuum cleaner characterized in that a switching element is connected between a light emitting element at the end and a power source.