CN2060866U - Computer controller for refrigerator or cold cupboard - Google Patents

Abstract

At present, the electric control of the refrigerator adopts a temperature-controlling switch, a delayer and some other ordinary devices, and thus the function is simple and the fault rate is high. The utility model, a micro computer controller for refrigerator control developed by utilizing a microcomputer SCM (containing a cold cupboard), can be added with functions of temperature display, various defrosting function, over and under voltage protection and power-off time-delay protection, etc. The controller can receive and process inputting signals by an 8035 SCM, and measure the temperature of the refrigerated chamber by an SL134 (temperature sensor). The signals enter an LM324 after passing through a 4053, and then are converted into pulse signals by a time-base circuit slice 555 to be input into the No. 1 pin b of the 8035, and the 8035 controls a compressor, etc. The temperature is displayed and controlled by a display circuit composed of three LED digits and two slices of 73L164.

Description

Computer controller for refrigerator or cold cupboard

The utility model relates to the controller of refrigerator, refrigerator, refers to refrigerator especially.Temperature detect switch (TDS) is adopted in the control of refrigerator, refrigerator more, parts such as chronotron, and these device functions are comparatively single, and failure rate is higher.

The purpose of this utility model is to propose a kind of refrigerator, temperature controller, chronotron, the defrost temperature controller of refrigerator computer controller to be replaced in refrigerator, refrigerator; refrigerator protector etc., and have temperature demonstration, multiple defrost function; overvoltage/undervoltage protection, and multiple function such as outage time-delay.

Scheme of the present utility model is as follows: regulator block 7805,7812 is formed the stabilized voltage supply parts, to complete machine provide+5V and+the 12V power supply, provide the fluctuation DC voltage for relatively for overvoltage/undervoltage detects simultaneously.Sensor SL134 is transformed into the correspondent voltage value with temperature value, after multi-way switch MC4053 samples respectively, the signal of a chamber of gating enters the high power amplifying circuit that LM324 forms, send into the voltage-frequency converter that constitutes by NE555 through the voltage after amplifying, convert magnitude of voltage to a series of corresponding square-wave signals, enter microsystem by the T0 of single-chip microcomputer 8035 end and detect.The pulse width values that records under the standard temperature is deposited among the EPROM2716, utilize relative method can detect actual temperature value in the refrigerator, this actual temperature is compared with design temperature, output is opened, stopping signal control compressor operating.

Elaborate to the utility model below in conjunction with accompanying drawing.

Fig. 1 is a theory diagram of the present utility model.

Fig. 2 is this controller detecting unit hardware block diagram.

Fig. 3 is the family curve of this controller sensor.

Fig. 4 is this controller overvoltage/undervoltage testing circuit schematic diagram.

Fig. 5 is this controller microsystem schematic diagram.

Fig. 6 is the connection layout of single-chip microcomputer and display part.

Fig. 7 is the MOVDPPA sequential chart.

Fig. 8 is the utility model control section connection layout.

Fig. 9 is software main program figure.

Figure 10 is a specific embodiment circuit diagram of the present utility model.

With reference to Fig. 1 the utility model is core with the single-chip microcomputer, can be 8035 slice, thin pieces in the MCS-48 series, the 8035th, a kind of computing machine stamen sheet of high integration, inside comprises clock circuit CPu, parts such as RAM and I/O interface, with these partly integrated dual inline types (40 pin) of dressing up, with refrigerating chamber, temperature of refrigerating chamber converts voltage signal to through sensor, through shaping, 8035 T0 end is delivered in filtering, with the detection that software is surveyed wide its temperature of realization, after machine is handled as calculated, deliver to display unit displays temperature result on the one hand, on the other hand, compressor and well heater are controlled.With reference to Fig. 2 temperature detecting unit by integrated temperature sensor SL134, analog switch MC4053, amplifier LM324 and formed by the voltage-frequency change-over circuit that NE555 forms.Integrated temperature sensor SL134 temperature-sensitive scope is between-50 ℃～150 ℃, and sensitivity is 10mv/ ℃, and its output characteristics is seen Fig. 3.Two sensor SL134 are placed appropriate location freezing, reefer respectively, analog switch MC4053 is delivered in the output of sensor, respectively temperature freezing, reefer is detected according to signal condition from 8035 single-chip microcomputer P24, "+" end of its signal voltage being delivered to LM324 amplifies zeroing.Amplifier LM324 takes the power work mode, form the amplification filtering network, again processed signal voltage is imported the voltage-frequency change-over circuit of being made up of NE555, the square wave that output changes along with signal voltage, detect the width of square wave with computing machine, just can realize the variation to the detection square wave width of its temperature, be exactly variation of temperature.

With reference to Fig. 4, refrigerator refrigerating part compressor operating voltage is 220V, all is in abnormal working position during greater than 245V or less than 175V at voltage, and should stop compressor and play a protective role this moment.The fluctuation of line voltage causes that the variation of output voltage V out utilizes LM324 to form comparer, with the dividing potential drop of 12V as a comparison voltage carry out the detection signal of overvoltage/undervoltage, when P25 is high level, for superpotential when P23 be under-voltage during for low level.

The temperature setting of this controller is set by toggle switch, and toggle switch is exported 8421 radix-minus-one complements, detects by computing machine, realizes different control.

Referring to Fig. 5,8035 single-chip microcomputers are by ALU (ALU), data memory (RAM), totalizer (ACE), three parallel input/output interfaces of 8 bit timings/counter (CTC) (P1, P2, BVS), three input test lines (T0, T1, INT) independently separately, order register (IR), programmable counter (PC), program status word register (PSW) and clock circuit, reset circuit is formed.

8035 single-chip microcomputers are because no internal processes device, so native system uses 8035 outside expansion ROM modes, used a slice 2716 as the memory under program 8035 of 8035 single-chip microcomputers with 2716 to be connected be by an address latch 74ls373 high 3 as the signal 2716 of address wire least-significant byte A0～A7 of 2716, link to each other with low 3 of 8035P2 mouth, constituted 11 bit address.This is because 2716 are a kind of memories that can rewrite, has the capacity of 2K.8035 single-chip microcomputers all are by the BUS mouth with being connected of peripheral stamen sheet, and 8035 BUS mouth both linked to each other with the data of peripheral stamen sheet, and the address wire with peripheral stamen sheet links to each other again.In this control system, 74LS373 is 8 latch stamen sheets, their functions of undertaking the address latch in the counting unit circuit.

8035 single-chip microcomputers have clock oscillation circuit, will make it vibration as long as insert quartz crystal oscillator circuit on XTAL1 and the XTAL2 pin sheet outside, produce clock and export.Native system inserts the quartz crystal of 4MHE, produces 8035 main synchronous clock TC～1.333MHE through state 3 frequency divisions.

With reference to Fig. 6, display unit circuit is made up of the digital display tube of three LED and two 74LS164, and three LED adopt the common cathode connection, and one of them is a sign bit, all the other two is that numeral shows that 74 LS164 are connected with single-chip microcomputer by SI PO shift register.74LS164 is a kind of 8 bit shift register that seal in and go out, and has shown among the figure how 8035 link to each other with LED by 74LS164.The 8243rd, a kind of is the I/O extender of MCS-48 series monolithic special setting, four special instruction: MOVDPI, A, ANLDPiA, ORLDPiA are arranged in the MCS-48 series of instructions system, and Ci=4～7 these several instructions aim at the service of 8243z/O extender.

With reference to Fig. 7, ALE is that the address allows latch signal, PSEN is the program gating signal, and PROG is expansion mouthful signal, as can be seen from the figure, when PROG is rising edge, P20～P23 is data, P20 is received input A, the B end of 74LS164 and carries out MCVA, OIH, MCVDPiA, and a high level is sent into 74LS164, after carrying out MOVAOOH, MOVPPA a low level is sent into 74LS164, so just can realize its Presentation Function.

With reference to Fig. 8, the controller controlling object has two: one is compressor, and one is electric resistance heater, uses bidirectional triode thyristor as gauge tap.As P26(P27) when being high level, T1(T2) current collection low level very BCR1(BCR2) is cut-off state, not conducting.Compressor (resistance wire) is not worked.As P26(P27) when being low level, trigger end BCR1(BCR2) is a high level, BCR1(BCR2) conducting, compressor (resistance wire) work is P26(P27) by Single-chip Controlling.R1C1 is the BCR1 rc protection circuit, and R2C2 is the rc protection circuit of BCR2.

System software also comprises a plurality of subroutines of time delay subroutine (with reference to Fig. 9) except that master routine.This controller adopts the control of delaying time of CTC timing mode, and clock frequency is 4M, and the input pulse of CTC is 15 * 32 frequency divisions of crystal oscillator frequency in the single-chip microcomputer, and then the pulsed frequency of CTC is:

4MHZ÷15÷32＝9.8KHZ

Time cycle is: 0.102ms

If count with an eight bit register, then the maximum count time is:

256×0.102＝20.112ms

Per 16 maximum count time is 256 * 26.112=6.684672 minute.Time-delay is except 16 digit counters, and with an eight bit register counting, its time constant that should send is about again:

360÷6.684＝45D＝2DH

Count with the CTC operation so send into the register time constant, when its counter all was " 0 ", promptly delay time arrived, thereby realized the effect of time-delay.Equally, also to adopt realization in the same way in 10 hours.

The detection of temperature value:

Mentioned in the hardware circuit introduction of front convert variation of temperature to pulse the variation of width as long as we detect the variation of pulse width, just can determine the variation of refrigerator temperature.Deposit among the EPOM2716 according to the pulse width values that under standard temperature, records, utilize relative method just can determine the actual temperature value in the refrigerator, thereby finish the detection of temperature.

MCVA A zero clearing

TEXT JTO TEXT looks for negative edge

TEXT2 JNT0 TEXT2 looks for rising edge

TEXT3 WCA A－→A

JTO TEXT3 TO is the high TEXT3 of commentaries on classics

So just can realize the width detection of its square wave, finally obtain its actual temperature value with software.

Native system shows and shows with tabling look-up, and the temperature value that detects meter is sent among the A, takes out the number of putting in advance the memory under program that will show from corresponding demonstration storage portions again, carries out the output of display port, thereby reaches the purpose of demonstration.

Claims (1)

1, refrigerator, refrigerator computer controller, provide 15V to 12V dc supply by transformer, it is characterized in that receiving by 8035 Single Chip Microcomputer (SCM) system, handle input signal, promptly record the temperature of reefer by SL134, after 4035, enter LM324, convert pulse signal to by 555 again and import 8035 No. 1 pin b; Temperature shows and control that form display circuit by three LED charactrons and two 74L164, LED adopts the common cathode connection, uses bidirectional triode thyristor BCR ₁, BCR ₂Be the handing-over of strong and weak electricity, control compressor and heating wire heating.

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