JPS59172002A - Air cleaning device - Google Patents

Abstract

PURPOSE:To eliminate noises and attain assured working of an air cleaning device by securing the synchronism between the output of a photodetecting element and the light emitting cycle of a light emitting diode and converting said output into an extended pulse signal. CONSTITUTION:A smoke sensor 3 detects smoke particles, and an air cleaning device like a ventilating fan, etc. is actuated via an off-delay timer at a control part. The sensor 3 drives intermittently a light emitting diode through a light emitting drive part 8 to emit light. Thus the smoke particles disperse the emitted light, and these dispersed beams are received by a photodetecting element 2 and detected at a level deciding part 10. This detection signal is synchronized with the light emission of the diode 1 and at the same time delivered in the form of a pulse signal extended to the prescribed pulse width. For this purpose, a pulse extending part 12 is formed with a synchronizing pulse charging part 15 and an output pulse part 16. Thus an output pulse containing no noise component is obtained.

Description

[Detailed Description of the Invention] [Technical Field] The present invention monitors the presence or absence of smoke indoors, particularly in a relatively narrow room such as the inside of a car or an airplane, and
This invention relates to an air purifying device that automatically operates air purifying devices such as ventilation fans and air purifiers when the smoke concentration in a room increases.

[Background technology]

FIG. 1 shows a general block diagram of this type of air purifying device, showing a smoke sensor (3) placed in the room to be purified, and the air generally separated from the smoke sensor (3). Control unit (6) installed near the cleaning equipment (6)
, an air purifying device (5) such as a ventilation fan or an air purifier that purifies indoor air, and a power source (Iη) that supplies power for circuit operation to the smoke sensor (3) and control unit (6). The smoke sensor (3) monitors the smoke concentration in the room, and when the smoke concentration in the room reaches a predetermined level 1 or higher, the air purification device (5) is activated by the output of the control section (6). By the way, in the above-mentioned system, the conventional smoke sensor (3) is as shown in Fig. 2 (
As shown in a), there is a type that outputs an analog signal according to the smoke concentration, and as shown in diagram (b), there is a direct current type that turns on and off depending on whether the smoke concentration is at a predetermined level 1 or higher. There are two types available: a model that outputs 1 stamen output (No. 4). However, in the conventional example, in the former type of Ana 0-Ll-1, It is susceptible to electrical noise that is superimposed on the output signal, and has the problem of a large risk of malfunction, and in the case of the latter type that outputs an on/off signal, it is difficult to directly use the output from the smoke sensor (3). It is configured so that the air purifying device (5) can be operated at
Since most of the functions of 6) are placed on the smoke sensor "j t31," the circuit load on the smoke sensor L3+ 1tllJ is large, and the circuit configuration 7 of the smoke sensor (3) is
5i In addition to having problems that become more complicated, when trying to obtain a signal output of two or more values, the smoke sensor (3) and control unit (6) are required.
The problem was that there was no choice but to increase the number of signal lines between the two. Furthermore, when using either of the above-mentioned types of smoke sensors (3), the control section (6) sets No. 48 on the smoke sensor (3) side to a predetermined detection level L. The configuration is such that the output detected by the level j directly controls the on/off of the air purifier (5), and air purification is performed during the period t□ to t2 and the period t3 to t4 in Fig. 2. g#I equipment (5)
Since the smoke concentration in the room is set to a predetermined detection level L. If there were fluctuations in the vicinity, there was a risk that the air purifying device (5) would repeatedly turn on and off, causing a flapping phenomenon. That is, especially when the room to be cleaned is a narrow space such as the inside of a car or an airplane, the effect can be achieved relatively quickly when the air purifying device (5) is activated. This results in a rapid decline in the smoke rating &, but in the past, the operation of the air purifying equipment (5) was immediately stopped when the smoke concentration fell below a predetermined level, so the smoke concentration in the room ended up decreasing. When the air purifying device (6) is repeatedly turned on and off in the vicinity of the above-mentioned predetermined bell, the air purifying device (6) repeatedly turns on and off, causing a flapping phenomenon, making it difficult to obtain good control of the device. Ta.

[Purpose of the first person] The present invention eliminates noise components well and can accurately determine smoke concentration without malfunction, but the circuit load on the smoke sensor side is small, and the smoke sensor can be miniaturized. It is possible to reduce the cost, and even when cleaning the air in a relatively small room, the control of the air purifying device often fluctuates, so it is not possible to control the air purifying device in a stable manner at all times. The object of the present invention is to provide an air purifying device that can be obtained.

[Disclosure of the invention]

The present invention is similar to the system shown in FIG. 1 in that the smoke sensor (3) and control section (6) are configured as described below. The smoke sensor (3) receives the light scattered by the smoke particles of the light from the light emitting device 1) which is generated intermittently by the light receiving element-F (2), and also uses the output of the light receiving element (2) as described above. It is configured to output a pulse signal that is synchronized with the light emitting cycle of the light emitting diode (IT) and extended during a predetermined pulse.As a specific circuit example, as shown in FIG. ) constant voltage circuit (7
) and a sampler pulse of a predetermined period to cause the light emitting diode 1) to emit light with the output of the sampler pulse, and a light receiving element that receives the light scattered by the smoke particles of the light emitting diode +1). (2); a level determination unit (10) that applies a predetermined voltage to the output of the light reception amplifier J unit (9) and determines the level using a bell; The capacitor (11
), and a pulse stretching section (12) that charges the pulse and stretches it to output the full pulse. R1-R2 in the convex figure
g is a resistor, D1 to D3 are diodes, C1 to C8 are transistors, Trl to Tr9 are transistors, and ZD is a Zener diode. Also, capacitors C1 and C3f
In the through-through cocidenser, all the parts overlapped by the broken lines in Fig. 3 are electrostatically shielded so as not to be affected by electrical noise. Therefore, the operator OP1 constitutes a level determination section (10), and this operator
A synchronous pulse charging section (1 section) is constructed by charging a capacitor (river) via a resistor RI9 by a series circuit of the output stage transistor of Pl and a transistor Tr8.This synchronous pulse charging section (15) is connected to an au pair. ,,7puO
The capacitor (11) is charged when an output is generated at P+ and the transistor Tr1 which is in trouble is on. The pulse output section (16) is composed of a circuit centered on the shortened operational amplifier OF2, and the terminal voltage of the capacitor (11) is level-detected by the shortened operational amplifier OF2 to perform pulse extension and control. output to section (6). FIG. 4 is an explanatory diagram of the operation of the convex circuit, in which the transistor Tr2 is
The collector voltage changes as shown in FIG. 4(&), and a current as shown in FIG. Here, the duration of the sand link pulse is 500 μs, and the repetition period is 0.5
It is g. Next, the output of the light-receiving amplifier section (9) which amplifies the output of the light-receiving element (2) is connected to both ends of the resistor R14.
A signal as shown in c) will be generated.

In FIG. 4(c), N(ri) is a noise component, and only the fc signal synchronized with the sash printer pulse in FIG. 4(a) is an actual smoke detection signal. lO) is determined by the level L1 in Figure 4(c), and the pulse extension is 8<02+ capacitor (11).
is charged by the output of the level determination section (10), and at this time, the output of the level determination section (10) is charged by the transistor T.
This is to charge the capacitor (11) via r8, and since transistor Tr8 is turned on in synchronization with the above-mentioned sash printer pulse, part of the signal shown in FIG. The noise components that do not occur are removed, and the voltage at the terminal of the capacitor (11) as shown in the same figure (d) is obtained. Part θ
6), the output voltage of the capacitor (II) shown in (d) of the same figure is determined by level L2, and as shown in (e) of the same figure, the pulse is extended to 150 m5 and the repetition frequency is set to 150 m5. Next, the control unit (6) inputs the output pulse of the smoke sensor (3) and removes a noise component by pulse subtraction and pulse 1p, and also removes this noise component. The signal is configured to operate air purifying equipment such as a ventilation fan or an air purifier via an off-delay timer (4).As a specific circuit example, as shown in Fig. 5, a smoke sensor A pulse input section (13) integrates the input pulse signal 8' from (3) and then discriminates the level to remove noise components depending on the pulse height and pulse width. It is composed of an off-delay timer (4) that delays for a certain period of time, and a device control section (14) such as a relay output circuit that is driven by the output of the off-delay timer (4) and operates the air purification device (5). ing. In the circuit shown in Fig. 5, R1 to R1o are resistors, 01 to c2 are capacitors, 艮~D3 digit tie auto, Tr is a transistor, oPl, OP2/-i au pair υ
``j'' shows the pulse input section (resistor 1, R
2 and capacitor C1, integrates only the input section as shown in Figure 0 (b)).
) is obtained at both ends of the capacitor c1, and then the level is detected by the comparator oP1 at the detection level L3 to obtain an output as shown in FIG. 4(c).

Here, N in Figure 0 (b)) is a heavy noise component that is transmitted to the signal line between the light receiving element (2) and the control unit (6), and this is shown in Figure ←) (c). As shown in K', the pulse input section (
It is removed at the stage of integration and discrimination in step 13). Next, the capacitor C2 is charged via the resistor R5 and the diode D2 by the output of the pulse input section t131 as shown in FIG. This is determined by the detection level L at the fparator OP2, and an output signal as shown in the figure (e) is sent to the output terminal of the off delay timer (4), which is configured around the capacitor C2 and the comparator OP2. This off-delay timer (4
) becomes approximately 0 after the output of the pulse input section (13) disappears.
4I& is configured so that the output returns to the off state after 0 seconds. In this way, when an output like the one shown in the figure ←) is generated at the output terminal of the off-delay timer (4), the transistor Tr of the device control section (I4) is turned on, the relay Ry is energized, and the air is supplied to the contact r. The cleaning equipment (6) will be activated.

〔Effect of the invention〕

As described above, the present invention has a smoke sensor that outputs the output of the light receiving element as a pulse signal that is extended during the light emission period of the light emitting diode and into a predetermined pulse.
Although noise removal in the smoke sensor is good and reliable, the circuit load on the smoke sensor side is small, and the circuit configuration is simplified and stabilized. By changing the number of signal lines, it is possible to freely obtain a multi-value output of two or more values without increasing the number of signal lines, and it has the effect that noise components can be effectively removed during @ signal transmission. It is also equipped with a control unit that inputs the output pulse of the smoke sensor, removes noise components through pulse compression and during the pulse, and uses the signal from which this noise component has been removed to operate the air purifying equipment via an off-delay timer. Therefore, the noise components mixed on the signal line from the smoke sensor are removed to ensure that there is no risk of malfunction, and the smoke concentration in the room to be cleaned is lower than the detection level of the smoke sensor. Furthermore, it is possible to keep the air purifying equipment running for a certain period of time.
In particular, when purifying the air in a small room, the smoke concentration level in the room rises and falls near the above detection level, and the control of the air purifying equipment does not fluctuate, ensuring stable control at all times. It has the effect that it can do.

In particular, in the embodiment set forth in Ilf claim 2, the smoke sensor v'' supports the constant voltage circuit, so that malfunctions do not occur due to noise components superimposed on the power supply, and stable operation is always possible. Since it has a level determination section that applies a predetermined voltage to the output of the light receiving amplifier section and uses a bell to determine the level, it is possible to reliably detect when the indoor smoke concentration has fallen below a predetermined level. The capacitor is charged and a stretched pulse is output in synchronization with the sampling pulse by the output of the pulse determination unit.Since it has a pulse stretching unit, it is possible to reliably eliminate noise components that are not synchronized with the printer pulse. Since it outputs a signal with a stretched path, it has the effect of being less affected by the noise superimposed on the signal line from the smoke sensor to the control unit, and has the effect of reducing the effects of Since there is no need to convert it to an OFF DC level signal, there is no need for a large time constant circuit or multi-stage time constant circuit as in the past, reducing the circuit load. The circuit configuration also has the effect of being simple and inexpensive.Next, in the embodiment described in claim 2, the control section discriminates the integrated level of the input pulse signal from the smoke sensor and determines the pulse height and the pulse duration. Since it has a pulse manual part that removes noise components, it has a simple configuration and is
1) It is possible to reliably remove the noise components mixed on the surface, and even when the output on the smoke sensor side is set to a single output from a multi-value meter, it can be handled more flexibly by changing the integration time constant, etc. It is effective.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of a general air purification system, Figure 2 (B)) (b) is an output waveform diagram of different conventional smoke sensor outputs, and Figure 5 is a diagram of the output waveform of a conventional smoke sensor. Example smoke t'J
The circuit diagram of Sun, Figure 4 is the time chart of the same as above,! @Figure 5 is a circuit diagram of the control 73B same as above, and Figure 6 is a time cisade same as above, where (1) is a light emitting diode, (2) is a light receiving element, (3) is a smoke sensor, and (4) is an off delay timer. ,(
5) is an air purifying device, (6) is a control unit, (7) is a constant voltage circuit, (8) is a light emitting drive unit, +911d light receiving amplifier,
(10) is the level judgment part, (11) is the koshijinsa, (I
2) is a pulse extension part, (+'al is a pulse input part,
(14) is a device control section. Agent Patent Attorney Ishi 1) Choshichi

Claims (3)

[Claims] (1) A light-receiving element receives the light scattered by the smoke particles of the light-emitting diode that emits light intermittently, and the output of the light-receiving element is synchronized with the light-emitting cycle of the light-emitting diode and extended during a predetermined pulse. A smoke sensor that outputs a pulse signal and the output pulse of the smoke ty"j are input, noise components are removed by the pulse height and pulse width, and the signal from which this noise component is removed is sent to the ventilation fan or air via an off-delay timer. An air purifying device comprising a control section that operates an air purifying device such as a purifier. (2) The smoke sensor includes a constant voltage circuit that supplies power at a stabilized predetermined voltage to all circuits of the smoke sensor, and a light emitting device that oscillates a sampling pulse with a predetermined period and causes a light emitting diode to emit light with the output of the sampling pulse. a driving section, a light receiving amplifier that amplifies the output of the light receiving element that has received the light scattered by the smoke particles of the light of the light emitting diode, and a level determining section that determines the level of the output of the light receiving amplifier section at a predetermined voltage level; and a pulse stretching section that charges nde y+j and outputs a stretched pulse in synchronization with the sample pulse using the output of the level determining section. Air purification device as described in section. (3) The control section includes a pulse input section that integrates the input pulse signal from the smoke sensor, then discriminates the level and removes noise components based on the pulse height and pulse width, and controls the off-time of the output of this pulse input section. The air purifier according to claim 1, comprising an off-delay timer that delays for a certain period of time, and a device control section that is driven by the output of the off-delay timer to operate the air purifying device. conversion device.