JPS6152371B2 - - Google Patents

Description

[Detailed Description of the Invention] In general, if the filter of an air conditioner becomes clogged, the cooling, heating, and dust removal abilities of the air conditioner will be affected. It is necessary to notify the

Therefore, it is conceivable to accumulate the operating time of the air conditioner itself, and notify the user of the need to clean the filter when the accumulated time reaches a certain amount, but according to this method, the indoor air Effects such as dirt are ignored. However, indoor air pollution varies considerably depending on usage conditions, and is not a factor to be ignored.

In view of the above reasons, the present invention measures the temperature near the air inlet and the air outlet, and when the temperature difference between these reaches a certain amount, notifies the user that the filter is clogged. This system compensates for the influence of dirt on the filter and accurately reports the degree of dirt on the filter.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. 1 and 2 are an external perspective view and a sectional view taken along line A-A' of an air conditioner in which the clogging alarm device of the present invention is implemented, in which 1 is the conditioner main body, 2
3 is an air inlet, and 3 is an air outlet. Reference numeral 4 denotes a filter provided at the suction port, which is detachably installed in the main body 1. A heat exchanger 5 is a part of the refrigeration cycle, and is maintained at a low temperature using a refrigerant such as fluorocarbon gas. 6 is a ventilation fan. 7 and 8 are near the suction port 2 and the blowout port 3, respectively.
For example, a thermistor is used as a temperature detector provided nearby. Reference numeral 9 denotes a micro switch that is turned on and off in conjunction with the insertion and removal of the filter 4.
Reference numeral 10 denotes a remote control box in which an operation switch, a control section, etc. of the air conditioner are housed. 11 is a clear key switch which will be described later.

In FIG. 2, air sucked in from the air suction port 2 passes through a filter 4 to remove dust, passes through a heat exchanger 5 for heat exchange, and further passes through a fan 6 and is blown out from the air outlet 3. In other words, air flows in the order of arrows a→b→e.

Therefore, during operation of the harmonizer, the temperature of the air blown out is lower than the temperature T of the air sucked into the suction port 2.
T1 is getting lower. This temperature difference (T-T1) is not only related to the capacity of the refrigerator, but also depends on the air volume. That is, when the air volume is large, the temperature difference is small, and when the air volume is small, the temperature difference becomes large.

The present invention focuses on this point and detects the clogging of the filter 4, taking advantage of the fact that when the filter becomes heavily soiled, the air volume decreases and the temperature difference increases. FIG. 3 is a block diagram of an air conditioner embodying the present invention, in which a control section 12 consisting of a microcomputer is housed in a remote control box 10, and a clogging alarm LED is driven by a signal 19 from the control section 12. Clogging alarm circuit 13, reference clock signal P generation circuit 1
4. It consists of a series connection circuit of the clear key switch 11 and the micro switch 9, and a temperature detection circuit 15 including the temperature detectors 7 and 8.

Note that air conditioners whose operations are controlled by digital control circuits such as microcomputers have smaller control units, and the ability to easily set complex conditions.
It has recently become popular due to its features such as ease of input instructions from the outside, and diaphragm switches have been used instead of conventional slide switches and lock switches to instruct various conditions such as timer settings and automatic operation. Switch,
Switches such as snap-action switches that allow input with just a light operation, i.e. key switches similar to those used in calculators (pressing to turn on, releasing to prompt off) are used, and all of the keys are There are many configurations in which the remote controllers are collected in the same remote control box.

The operation control section 12 has a built-in digital counter that counts the reference signal P during each operation of the harmonizer main body 1 (while the fan 6 is rotating). This counter counts the signal P to measure the total operating time of the harmonizer main body 1. When the counted amount exceeds a certain value, that is, when the total operating time exceeds a certain value, the control unit 12 sends an alarm to the above-mentioned both temperatures. A signal is generated to detect the temperature difference between the detectors 7 and 8.

The micro switch 9 and clear key switch 11 are for clearing the contents of the digital counter in the control unit 12, and are used to clear the contents of the digital counter in the control unit 12.
A clear signal can be generated by removing the filter 4 from the filter, turning on the switch 9, and then pressing the clear key switch 11. Therefore, even if the clear key switch 11 is pressed with the filter 4 attached to the main body 1, no clear signal is generated. In this way, the contents of the digital counter will not be cleared even if the clear key switch 11 is operated by mistake when the control key switch disposed on the remote control box 10 is operated.

Further, in this case, compared to the case where the switches 9 and 11 are connected in parallel to the control section 12, the number of terminals of the microcomputer can be reduced, which is advantageous in terms of the circuit configuration.

Next, the operation of the temperature detection circuit 15 will be explained with reference to FIGS. 4 and 5. In the figure, S1 and S2 are analog switches that are turned on by signals P1 and P2 from the control unit 12, 16 is an integrator, and 17 is a comparator, and the reference voltage -E1 for comparison is applied to the + input terminal. . A pulse generating circuit 18 generates a feedback pulse P3 based on the output of the comparator 17.

The temperature difference detection signals P1 and P2 are generated at predetermined time intervals when the digital counter reaches a predetermined count and 30 minutes have passed since the harmonizer started operating. Power is always supplied to the control section 12 regardless of whether the harmonizer is in operation, and the total operating time is always maintained in a digital counter. Also, to determine whether 30 minutes have passed since the start of operation, a separate counter section within the microcomputer is used to measure the time. This counter section is repeatedly executed, and thereafter, during operation of the harmonizer, signals P1 and P2 for detecting a temperature difference are generated every 30 minutes.

Now, when the total operating time of the harmonizer reaches a predetermined time (for example, 60 hours) and 30 minutes have passed since the start of operation, a signal P1 for detecting a temperature difference is supplied from the control section 12 to the analog switch S1. When analog switch S1 is turned on, the resistance value of thermostat 7 and resistance R correspond to the temperature of the intake air at that time.
A positive input unknown voltage vi divided by 1 is applied to the input terminal of the integrator 16. When vi is added, the integrator 16 starts integrating in the negative direction with an integral value determined by the time constant of RC (C is _a capacitor). At the moment the output of the comparator 17 changes from LOW to HIGH, the pulse generation circuit 18 is triggered at the rising edge. In response to this trigger, the pulse generating circuit 18 outputs a constant pulse P ₃ having an amplitude E ₂ and a pulse width t ₁ as shown in FIG. The output P3 is applied by the integrator 16 in a direction opposite to the direction in which the output increases.

In the above operation, the output of the integrator 16 is the comparison voltage -E
It repeats each time it reaches 1, and continues so that the average value of the pulses P ₃ fed back to the input with opposite polarity is equal to the input unknown voltage vi. The shaded area in Figure 5 is the pulse
This is the average value of one cycle of _P3 .

At this time, the operation control section 12 receives the reference clock signal P.
Pulses _P3 generated during a certain time period t2 based on t2 are counted and stored in the storage unit.

Next, the operation control section 12 stops generating the signal P1 and turns off the switch S1, and also generates the signal P2 and turns on the switch S2. Then, since the resistance value of the thermostat 8 corresponding to the temperature of the blown air and the positive unknown input voltage divided by the resistor R1 are input to the integrator 16, the temperature of the blown air is determined in exactly the same way. The corresponding pulse P3 is counted and stored in another storage section. Then, the number of pulses corresponding to the temperature near the air intake port 2 and air outlet 3 is calculated (in the case of a refrigerated model, the air outlet side pulse is subtracted from the air intake side pulse), and the pulse value is greater than a certain value. At the time, the display signal 19 is sent to the notification circuit 13
Output to. If it is below a certain value, it is assumed that the degree of dirt on the filter 4 is not too bad, and the display signal 19 is displayed.
Clears the contents of the two storage units mentioned above without generating. In this case, the same operation is performed 30 minutes later to detect the temperature difference again.

When the display signal 19 is generated, the notification circuit 13 is driven and, for example, an LED emits light to notify the user that the filter 4 is clogged.

In the present invention, the temperature is measured after a certain period of time has elapsed after the heat exchanger is activated after the power is turned on. Further, in the case of an air conditioner in which the air volume of the fan can be changed, the fan may be temporarily fixed at the same switching position, or the criterion for determining the number of pulses of the calculation result may be adjusted by the air volume switching position of the fan.

As described above, according to the present invention, it is possible to accurately notify the degree of contamination of the filter regardless of the degree of contamination of the air depending on the installation location of the air conditioner or the like.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view of an air conditioner embodying the present invention, Fig. 2 is a sectional view of the main parts, Fig. 3 is a block diagram of the main parts, and Fig. 4 is a clogging alarm device for the filter of the present invention. The main circuit diagram and FIG. 5 are time charts for explaining the operation of FIG. 4. 1: Air conditioner body, 2: Air inlet, 3: Air outlet, 4: Filter, 5: Heat exchanger, 6:
Fan, 7, 8: Temperature detector, 12: Operation control circuit.

Claims (1)

[Claims] 1. An integrating means for integrating the operating time of the air conditioner main body, a temperature detecting means provided near the air inlet and an air outlet, and when the integrating means has integrated a certain amount, the temperature detecting means detects the temperature of the air. A filter comprising a state determining means for detecting the temperature near the suction port and near the air outlet and determining whether the filter is clogged based on the temperature difference therebetween, and a filter clogging notification means for notifying the state of the state determining means. clogging alarm device.