JPH0353700Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for detecting changes in the filtration effectiveness of a filtration device for separating contaminants from a gas stream by indicating the change by means of a signal emitting means.

The detection principles known in the art for detecting the degree of blockage in air filtration system filters are not sensitive enough, and by the time a signal is emitted, the filtration system must be relatively heavily contaminated. It will get clogged.
This means that the filtration device may be operated with reduced filtration efficiency.

The object of the invention is to overcome this problem and to provide a simple and reliable device which provides a fairly sensitive detection function.

This applies to paragraphs 1 to 5 of claims for utility model registration.
This is achieved by providing the device with the features described in the section.

The present invention will be explained below based on the accompanying drawings.

1 is a schematic diagram of a filtration device having a device according to the invention, FIG. 2 is a schematic diagram of a voltage field, FIG. 3 is a circuit diagram of a coupling forming part of the device according to the invention, and FIG. 4 is a device according to the invention. It is a drawing which shows the connection state of a part of filtration cell and a detection transmitter in .

The illustrated devices include a voltage transformer 1 and a filtration device 2 for separating contaminants from gases, in particular for separating harmful substances from fumes originating from welding equipment.
Consists of. The filtration device 2 comprises an automatically driven fan 3 and one or several removable filters 4 with filtration means or filtration cells 5.
including.

As shown in FIG. 4, the filtration cell 5 includes an ionization unit 5a that generates positively charged ions.
, the positively charged ions positively charge the particles in the air stream passing through the ionization unit 5a (for example, the voltage in the ionization unit is approximately 8000V). The filtration cell 5 further has a collector unit 5c (so-called ionization unit) provided with so-called collector plates 5b, 5b.
The collector voltages (for example 4000 VDC) at collector plates 5b, 5b have the same potential (higher potential than ionization unit 5a).

Particles in the air stream pass through the aforementioned ionization unit 5a.
The particles acquire a positive charge when passing through the collector plates 5b, 5b, which cause the particles to pass through the collector plates 5b, 5b.
accumulate on top.

The fan 3 sucks the contaminated air 6 into the ionized sector 7 of the filtration device 2, in which the contaminated particles contained in the air stream become positively charged as described above. These particles are deposited on the aforementioned collector plates 5b, 5b of the negatively charged filtration cell 5.

As particles continue to accumulate on the aforementioned collector plates 5b, 5b of the filtration cell 5, the capacity to receive more particles decreases and the filtration effectiveness of the filtration device becomes insufficient after a period of use. become.

When particles adhere to the collector plates 5b, 5b, the collector voltage decreases. This change in collector voltage is used to detect and send signals to indicate degraded filtration before the filtration device continues to operate for an extended period of time with reduced filtration efficiency, or before filtration efficiency decreases to an unacceptable level. It is sensed within device 8 (eg, within A of FIG. 4).

If the collector voltage changes to such an extent that the filtering effect is unacceptable, the sensing and transmitting device 8 transmits a signal (light and/or audio signal). If the filtration continues with unacceptable filtration efficiency, the detection transmitter 8 issues a stop signal to the fan, ie the filtration is stopped.

The generation of light and/or audio signals may initially be intermittent, but if filtering continues, it becomes a continuous signal. The stop signal to the fan can also be sent some time after the collector voltage reaches the value of the stop signal.

The sensing transmitter 8 has inputs 10 and 1 indicating the voltage across the filter cell 5 (called the resonant voltage).
1 (see FIG. 3). Under normal filtration conditions, the voltage across the filtration cell 5 is between 110 and 124 V (see Figure 2), and the input resonator 9 does not apply any voltage to the buzzer 12 and lamp 13. , continue applying voltage to the relay connected to the fan 3 motor. Short circuits in the filtration cell 5 caused by contaminants clogging the filtration cell 5 and/or due to damage to the collector plate and/or due to destruction of the ionization cord (not shown) of the ionized sector. By effect. voltage is below 110V or
If the voltage exceeds 124V, the following will occur. That is, voltage transmission <108.5V Continuous buzzer sound Continuous lighting Fan motor contactor will open within e.g. 12 seconds; 108.5~110V Intermittent buzzer sound Intermittent lighting Contactor will not open; 110 ~124V No buzzer, no light, contactor does not open; 124~125.5V, intermittent buzzer, intermittent light, contactor does not open; >125.5V, continuous buzzer, continuous light, fan motor contactor For example, it opens within 12 seconds.

Opening of the contactor leading to the fan motor, i.e.
The stoppage of the fan 3 is preferably delayed by a number of seconds, for example 6 to 20 seconds, so that the fan 3 is not stopped due to the temporary passage of a metal object that temporarily reduces the voltage across the filtration cells. However, the voltage
If it remains below 108.5V or above 125.5V, the fan 3 is shut off and can only be turned on again after the dirty filter cell 5 has been removed or cleaned.

The above table of voltage values and transmission may naturally vary depending on the types of components of the detection and transmission device 8 or other components of the system.

Although the structure of the control circuit 9 may change, the third
The figure shows a practically useful and functionally superior device. The input resonant voltage is rectified and the voltage is divided and filtered. The level is trimmer partial pressure meter 1
4 and becomes the value of the cleanliness of the filter.

The aforementioned voltages are transmitted to comparators 15-18, the reference voltage being formed by the stable 24V from unit 19.

Comparators 16 and 17 signal at voltages of 124V and 110V, respectively, and comparators 15 and 18 signal at 125.5V and 108.5V, respectively. Comparator 16
and 17 actuate a pulse circuit 20, which supplies power to the buzzer 12 and the triac 21, which ignites the signal lamp 13. When either comparator 16 or 17 is activated, an intermittent optical and acoustic signal is obtained.

Comparators 15 and 18 block the activated pulse circuit and activate timer circuit 22, which after approximately 12 seconds interrupts the control current to triac 23, thereby opening the feeder contactor. . Unit 24 acts as a drive circuit for triac 23, and resistors 25 and 26 create a hysteresis of approximately 1V at the 124V and 110V levels, respectively, to provide a well-defined function.

The device according to the invention is not limited to the embodiments described above, but can be modified within the scope of the claims for utility model registration. The transmission can therefore take the form of a single lighting signal, only an acoustic signal, only a blocking signal, or a suitable combination thereof.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a filtration device having a device according to the invention. FIG. 2 is a schematic diagram of the voltage field.
FIG. 3 shows a circuit diagram of the coupling forming part of the device according to the invention. FIG. 4 is a diagram showing the connection state of a part of the filtration cell and the detection/transmission device in the device of the present invention. 1... Voltage transformer, 2... Filtration device, 3... Fan, 4... Filter, 5... Filtration cell.

Claims (1)

[Claims for Utility Model Registration] (1) A device for detecting a change in the filtration effect of a filtration device and displaying the change in the filtration effect, which device (a) separates contaminants from a gas flow; (b) a plurality of filtration cells in which contaminant particles in the gas flow are positively charged and the contaminant particles are deposited on the negatively charged filtration cells; (c) a detection mechanism for detecting a resonant voltage level between the filter cells, the detection mechanism comprising filtering means for filtering the resonant voltage; (d) (e) signal emitting means for emitting a signal when said resonant voltage exceeds a predetermined high voltage level or falls below a predetermined low voltage level; (e) in response to said emitted signal, display means; activating means for activating a predetermined additional voltage level above the predetermined high voltage level and intermittently operating at the predetermined high voltage level and the predetermined low voltage level; (f) after a predetermined time when said emitted signal is above or below said applied voltage level; An apparatus comprising: means for disabling said fan means. 2. The apparatus of claim 1, wherein the predetermined high voltage level is approximately 124V and the predetermined low voltage level is approximately 110V. 3 each of said predetermined additional voltage levels being approximately
125.5V and approximately 108.5V.