JPS60108663A - Absorption type refrigerator - 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 (a) Industrial Application Field The present invention is directed to an absorption type cold N1. It is related to storage.

(B) Conventional technology Conventionally, this type of absorption refrigerator has a burner installed below the generator, and fuel such as gas is supplied to this burner and burned in the burner, and the generator is heated by the flame. . Ignition of the flame is achieved by generating a spark in an ignition device installed in the burner, and this ignition control and fuel supply control are performed by a predetermined control circuit.

However, if the burner is not ignited due to some reason, such as an abnormality in the ignition system or wind, raw gas etc. are generated and there is a risk of explosion.

Furthermore, many of these types of absorption-type refrigerated FFI storages are used in vehicles, and the power supply of the control circuit tends to become unstable, resulting in abnormal control and damage to stored items.

(C) Object of the Invention The object of the present invention is to provide an absorption type refrigeration system which prevents inconveniences due to burner ignition failures, and prevents damage to elements and abnormal control due to abnormalities in the power supply of the control circuit.

B) Structure of the Invention The present invention provides an absorption refrigerator that operates by heating a generator with the flame of a burner, which includes: a valve device for controlling the supply of fuel to the burner; It consists of a control circuit that controls the ignition device, and the control circuit starts integration when the ignition device starts operating, and is reset when flame is generated in the burner and outputs a predetermined integrated pressure. preparing a timer means and a voltage detection means for detecting the voltage supplied to the control circuit and generating an output at a predetermined value or less;
- The ignition device and valve system are operated by a predetermined ignition signal, and the ignition signal is invalidated by the output of either the timer means or the voltage detection means (i'J).

(E) Embodiment FIG. 1 shows a schematic sectional view of this type of absorption refrigerator (1). The refrigerator (1) is an in-vehicle absorption type refrigerator particularly used in a camping car or the like. The refrigerator (1) uses, for example, ammonia as a refrigerant, and ammonia vapor is generated in a generator (3) installed at the back of an insulated box (2), condensed in a condenser (not shown), and then stored in a refrigerator compartment (4).
It is evaporated in a cooler (5) installed inside the refrigerator compartment (4), and the interior of the refrigerator compartment (4) is cooled using the heat absorption effect generated at that time. (6) is a door that freely opens and closes the front opening of the heat insulating box (2).

In order to generate ammonia vapor in the generator (3), it is necessary to heat the generator (3), and the heating means are an AC heater (7), a DC heater (8), and a burner (9). ). Each heating means operates separately, and both heaters (7) and (8) are connected to the generator (3).
) The burner (9) is attached directly to the outer surface of the generator (3) in a heat conductive manner, and the burner (9) is connected to the smoke pipe (g) attached to the outer surface of the generator (3) in a heat conductive manner.
A downward pressure is provided, and the heat generated by the burner (9) is transmitted to the generator (3) via this smoke pipe α0. This is a conduit for supplying gas as fuel to the α-side small burner (9), and is connected to a gas cylinder or the like (not shown). An electromagnetic on-off valve @ is interposed in the middle of the conduit α°C, and this valve (2) controls the supply of gas to the burner (9).

FIG. 2 shows the control circuit (to) of the refrigerator (1).

(DC) is a direct current power source such as a battery for a camper, and (AC) is a commercial alternating current power source.

The direct current power source (DC) is connected to the contact point tb of the double changeover switch (SW, ), and the alternating current power source (AC) is connected to the rectifier circuit Q4.
), the voltage is input to an AC voltage detection circuit (TRY), and is also input to a stabilizing circuit composed of a transistor (Try), a Zener diode (ZD), and a capacitor (C1). The stabilization circuit has a changeover switch (S
Direct current (DC) is also connected through the Wυ common contact (0), and the stabilization circuit becomes the power source for the subsequent electronic circuit (
V, D). Direct current power (DC) also has resistance (R
7) to the DC voltage detection circuit 00, and the power supply (
(2) DD) is input to the detection circuit 10 via the common contact (6) and contact (X) of the changeover switch (SWθ).

Here, the changeover switch (SWθ contact (not connected to alibi).The detection circuit (to) outputs a high potential (hereinafter referred to as rHJ) when the output voltage of the power supply (AC) decreases to, for example, 80V or less. When the voltage rises to 95V or more, the output becomes a low potential (hereinafter referred to as [L]), and the detection circuit 00 has a low potential when the input decreases to, for example, IOV.
becomes "H", rises to 10.5V or more, and rL
J.

An electromagnetic coil (l''h is connected between the output end of the detection circuit (1G) and the power supply (V power), and the tt magnetic coil a''h is excited and switched when the 1b force of the detection circuit u0 is 1-L. The switch (SW,) is closed to the contacts (al and (K)), and the contact (bl and (t)) is closed in the de-energized state. The output of the detection circuit 9 is further input to the alarm control circuit via the analog switch (2). (
2), and the output of the detection circuit Q5 is input to the analog switch -0 gate.

The output of the detection circuit Q0 is input to the AND gate 11 through the NOT gate (2) and the analog switch (E), and the output of the NOT gate is input to the AND gate @. The output of the AND gate (■) is input to the AND gate (C), and the AND gate (C) is further input with the 'output' of the switch (for example, when the car engine ignition switch is turned on, the output becomes "H"). (AND game) (The output of 213 is a light emitting diode (LED2) for DC operation indication, N
OIn'-Hl is input to the gate of the analog switch ■. The output of the NOR gate Q1) is connected to the power supply (VDD) via a resistor (R2) and
31).

(SW2) is manually opened and closed by the electric operation start switch, and is inserted between the power supply (VDD) and the resistor (R3).
The terminal potential of 5) is input to the gate of the analog switch Q and the AND gate OI). AND gate θ1)
The output of is input to the gate of analog switch (2).

2) is a thermistor (G) which senses the temperature of the cold room (4) or the temperature of the cooler (5), for example, has a negative characteristic with respect to temperature.
In order to maintain the temperature of refrigeration plan (4) at a substantially constant refrigeration temperature based on be.

The output of the temperature control circuit (2) is connected to the pace of the transistor (Tr, ) via an analog switch and to the pace of the transistor ('rrs) via the analog switch (1). The coil (c) of the relay switch (b) connected between the power source (AC) and the AC heater (7) in Figure 3 is connected to the collector of the transistor (Tr2), and the is the fourth
The coil of the relay switch (to) connected between the power supply (DC) and the DC heater (8) in the figure is connected, and each relay switch @masu is energized to its respective coil (to) θO to close the contact. It is something. Here coil wire 0Q
should be connected to the power supply (Vec), which is the input voltage of the stabilization circuit.

(SW, ) is a waste operation start switch, which is opened and closed manually, but it should not be closed at the same time as switch (SW, ). The switch (sWs) is electric #, (
Between the resistor (Rs) and the intervening resistor (Rs), the potential of the resistor (Rs) is applied to the AND gate (), the exclusive OR gate (hereinafter referred to as EXOR gate), and the inverter circuit (INV). is input. The first output of EXOR gate is EXOR gate (Foundation) and AND gate I
It is input to JI, and furthermore, a light emitting diode (
LEDm) K is connected. The output of the EXOR gate is input to the AND gate tn, and the output of the temperature control circuit (2) is further input to the ANI gate, and the output is also input to the AND gate Gli. AN
The output of the D gate... is the input terminal (51a) of the timer circuit 6υ.
) is entered. The timer circuit 6υ has an internal oscillator.
- It is a normal semiconductor timer and the input terminal (51a) is
11" and starts integration, and for example, after about 2 minutes, the fII
After completing the t calculation, the output terminal (51b) becomes l'-H-J. Furthermore, when the reset terminal (51c) reaches rLJ, the integration is stopped and reset. The output terminal (51b) of the timer circuit 6υ is connected to the inputs of the AND gate () and the EXOR gate (b). The output of the AND gate ring is connected to the pace of the transistor (Trs) and
An igniter circuit (IG) is connected between the collector of i'ra) and 'mcA (Vec). Igniter circuit (I
G) starts operating when the transistor ('i'rs) becomes conductive and outputs a periodic high voltage, and a spark plug (Sr) is connected to this output via a neon tube. . The spark plug (SP) is connected to a grounded burner (
9) It is installed so that it is exposed to the flame of the burner (9) nearby, and the burner (9) is activated by the output of the igniter circuit (IQ).
) that generates periodic ignition sparks.

The inverter circuit (INV) converts the DC voltage generated in the resistor (ILfi) into an oscillation transformer Q and a transistor (Tra
) etc., the output of the inverter circuit (INV) is applied to the ignition flag (SI) via the resistor (Ro), as well as the resistor (L) Ota) and the capacitor (C). Comparator 6 smoothes and removes the AC component.
4) is input to the (-) input terminal. A voltage dividing resistor (Re) (RIG) is connected to this (-) input terminal, and a diode (D) is connected between the power supply (VDD) and ground.
+) (Dt) and a capacitor (CI) (C4) are connected to prevent failures due to looping of the output of the IG circuit (IG). A reference potential is applied to the input terminal of the comparator (b) through a resistor (no) (Rn), and the output of the comparator 6a is connected to the EXOIL gate (
The signal is input to the reset terminal (51c) of the timer circuit 6υ via the NOT gate.

When a flame occurs in the burner (9), the impedance between the spark plug (SP) and the open burner (9) decreases, so the (-) input of the comparator r54) decreases, and the output of the comparator 54) becomes "H". However, before the burner (9) is ignited, the (-) input is higher than the (+l input), so the output is rLJ. Furthermore, a DC voltage is applied between the spark plug (SP) and the burner (9). In this case, there is a risk that soot or the like adhering to the ignition plug (SP) or the burner (9) may cause a short circuit between the two, but this configuration prevents such inconvenience.

The output of the ANDNO gate is a transistor (Tr?)
The electromagnetic coil □□□ that drives the valve (6) and the positive temperature characteristic thermistor j1G? are connected to the base of the transistor (Tr7) and the power supply (V, D). ) are connected in series, and further, resistors (R, , ) are connected in parallel to the thermistor 6η. As the positive temperature of the thermistor 5 increases, its resistance value increases, and as shown in Figure 5, the current flowing through the electromagnetic coil changes with the passage of time (t). This is due to the increase in resistance value due to self-heating of the 6D.Here, a relatively large operating current is required on the electromagnetic coil side at the beginning of opening the valve (2), but after that, a relatively small holding current can be applied. Therefore, by connecting a thermistor 5?), it is possible to secure the initial operating current and then reduce it, but with this alone, the value at which the current (10) is balanced will be as shown by the dotted line in Figure 5. Since there is a risk that the current will drop below the holding current of the coil 5e of the valve (A), the current value balanced by the resistor (RI3) is increased as shown by the solid line in Figure 5 to prevent the current (10) from decreasing. regulation and ensure holding current. As a result, the valve (6) opens properly and the current value decreases thereafter, so that the power consumption of the electromagnetic coil (6) can be kept low and less heat is generated, which improves safety in controlling gas.

The output of the detection circuit αQ is input to the ANDNO gate, and A
ND gate (4G output is E together with the output of timer circuit 6υ)
This becomes the input of the X OIt game l-θη. The outputs of () and () to the AND gate both become inputs to the alarm control circuit (e). The input of the alarm control circuit is “H” and the output is “H”.
This output has a buzzer (BZ) and a switch.
Switch (SW4) that opens and closes in conjunction with Sochi (SW3)
A light emitting diode for the gas pipe shaft (LED4) is connected to the light emitting diode for the electric obituary (LED4) through the analog switch.
LED, ) is connected. The output of the detection circuit Qf9 via the analog switch (branch) is connected to the gate of the analog switch 6@.

The operation will be explained using the above configuration. For example, a camper is parked at a campsite, a predetermined connector is connected to a commercial alternating current power source (AC), and a switch (SWI) is closed. (At this time, the switch (SW, ) is open.) At this time, the power supply (AC) is showing a predetermined voltage value, and the power supply (SW, ) is open.
), the output of the detection circuit QllG is l-L J, the coil αη is excited, the switch (SWt) is closed to the contact (al(a)), and the power supply (V
D,) is input to the detection circuit αG and 'l[1, storage (DC
), the output is rLJ and the output of NOT gate (2) is rHJ. Since the analog switch (2) is non-conductive, the output of the ANDNO gate 2) is rLJ and the analog switch (2) is non-conductive. The output of the NOT gate (g) is "l(" and the analog switch Q is conductive, so the light emitting diode (LEDI) lights up, the analog switch is conductive, and the output of the NOR gate ((9) is rLJ and A
The output of the NDNO gate (NDNO gate) is also "L", so the analog switch (2) is non-conductive and no alarm is generated. In this state, the AC heater (7) is controlled by the temperature control circuit to heat the generator (3), and the refrigerator compartment (4) is cooled.

Next, when there is no alternating current power (AC) at the campsite, or it is unstable and the voltage value drops and the output of the power source (AC) is 80
When the voltage drops below V or while driving, press the switch (
When SW2) is closed, the output of the detection circuit Qυ is r
Since I(J), the coil αη is de-energized and the switch (SW + ) is closed to the contact tb+ +g+.
At this time, the voltage of the battery, that is, the power supply (DC) is 10.5V.
If it is above, the output of the detection circuit αG is “L”, so N
OT gate (a) is I-I-IJ, analog switch (
C) is conductive, so the ANDNO gate output +t “H
J. If the engine switch is turned on at this time, AND
The NO gate output is a light emitting diode (LEDt) in Hol.
) lights up, the analog switch (2) is conductive, and the output of the NOT gate (g) is rLJ, so it is a NOR gate υ
is rLJ and the ANDNO gate is also rLJ, so the analog switch (A) is non-conducting and no alarm is generated, and the analog switch holder is also non-conducting.

In this state, the DC heater (8) is controlled by the temperature control circuit to heat the generator (3) and cool the refrigerator compartment (4).

In this state, the battery is discharged too much and the power supply (DC) is turned off.
When the voltage drops below OV, the output of the detection circuit (2) becomes ")1" and the N O'r gate (c) also becomes "L". As a result, the output of the ANDNO gate (c) becomes rLJ, and the analog switch () becomes non-conducting and the light emitting diode (LED
ri C lights out L, NOR'j-) 1a and AND goo) C3
The output of 1) becomes HJ, the analog switch (A) is conductive, the input of the alarm control circuit (C) becomes rHJ, the buzzer (BZ) sounds, and the analog switch (2) is conductive, so there is no electricity. The alarm light emitting diode (LED, ) lights up and alerts the user to alternating current power (AC) and direct current power (
(DC) has fallen below the allowable potential, and warns of the occurrence of a control malfunction.
) will be disabled.

Next, when heating the generator (3) with the gas burner (9), close the switch (SW,).
) is open. ), AND gate (c) t3b, E
A voltage (Vt, ) is input to the XOR gate (XOR gate) 1'7 and the inverter circuit (INV). At this time, the output of the timer circuit 6υ is still "L", so the output of the EXOR gate θη is "■~I", and the light emitting diode (LED, ) lights up, and the output of the comparator I5 (a) is also rLJ. Because there is EXOR
The output of the gate (7) becomes "H". At this time, if the output of the temperature control circuit (to) has reached rHJ, that is, the refrigerator compartment (4) has reached the predetermined upper limit temperature, the ANDNO gate output becomes "H", the transistor (Trs) conducts, and the igniter circuit (IG ) is working and plug (SP) and burner (9)
generate a spark between them. On the other hand, since all the inputs of the AND gate (6) are "I", the output is "H", the coil (to) is energized, the valve (6) is opened, and the gas flows into the burner (
9) and ignited, heating the generator (3) and cooling the refrigerator compartment (4). When a flame occurs in the burner (9), the output of the comparator 64J becomes rHJ, so the output of the EXOR gate is rLJ, which is the AND gate).
As a result, the operation of the igniter circuit (IG) stops. On the other hand, the timer circuit 6υ has started integrating since the igniter circuit (IG) started operating, but is reset because the NOT gate-like output becomes rLJ. When this cooling action progresses and the inside of the chamber (4) reaches a predetermined lower limit temperature, the circuit (
The output of 2) becomes rLJ, the output of the AND gate (to) becomes rLJ, the coil (support) becomes de-energized, and the valve (2)
is closed and the flame of burner (9) is extinguished. Repeat the above operations to cool the inside of the refrigerator to a predetermined temperature.

Next, if the burner (9) does not ignite in the above conditions due to the plug (SP) getting wet or the gas running out, the timer circuit 6υ will be integrated 2 minutes after the igniter circuit (IG) starts operating. ends. At this point, the output terminal (51b) of the timer circuit 6D is inverted, so E
When the output of the X OIt gate (L471 is rL), the light emitting diode (LED) goes out, and the ANDNO gate output becomes [L], the coil is de-energized, the valve (2) is closed, and the comparator is turned off. Since the output is also rLJ, the output of the EX wheel is rLJ and the operation of the igniter circuit (IG) is stopped.On the other hand, the output of the ANI (gate) is rHJ and W
The alarm is input to control circuit 4, the buzzer (BZ) sounds, and at this time, the switch (SW4) is also closed in conjunction with the switch (SW3), so the light emitting diode (LED4) for gas alarm is activated.
lights up.

Also, if both the alternating current power supply (AC) and the direct current power supply (DC) decrease in potential and the output of the detection circuit θQ becomes rHJ, A
The output of the ND gate (G) becomes r l - I J, the light emitting diode (LEDa) goes out as described above, the operation of the igniter circuit (IG) stops, the valve (2) closes, and the υ alarm control circuit goes off. is activated, the buzzer (BZ) sounds, and the light emitting diode (LED) for gas n warning lights up to notify the user of the abnormality. In this way, generation of raw gas from the burner (9) is prevented, malfunction of the flilJ control circuit port due to voltage drop is prevented, and failure of the contacts and each semiconductor element is prevented.

(f) Effects of the Invention According to the present invention, even if the fuel-powered absorption type cold gas is thick, the ignition operation will be stopped after a predetermined time and the fuel supply will also be stopped, thereby minimizing radio wave interference caused by large spots. Furthermore, in the case of products that use gas, it is possible to prevent the generation of raw gas, thereby preventing explosions and explosions.

Further, even when the voltage applied to the control circuit decreases, ignition and fuel supply are similarly stopped, so abnormal control can be prevented and damage to stored articles can be prevented.

[Brief explanation of the drawing]

Each figure shows an embodiment of the present invention. Figure 1 is a schematic side sectional view of an absorption refrigerator, Figure 2 is a control circuit diagram, Figure 3 is an electric circuit of an AC heater, and Figure 4 is a schematic side sectional view of an absorption refrigerator. FIG. 5 is a diagram showing the time course of current flowing through the coil of a solenoid valve. (1)...Absorption refrigerator, (3)...Generator,
(9)...burner, (2)...electromagnetic on-off valve,
OQ...DC voltage detection circuit, (SW,)...Gas operation start switch, 61)...Timer circuit, (SP
)...Spark plug. Figure 5

Claims (1)

[Claims] In an absorption refrigerator that operates by heating a l1 generator with a burner flame, the valve device controls the supply of fuel to the burner, the ignition device for the burner, and the valve device and the ignition device. and a control circuit that starts the operation when the ignition device starts operating, and is reset when a flame is generated in the burner, and a timer that generates an output at a predetermined product nK. and a voltage detection means for detecting the voltage supplied to the control circuit and generating an output below a predetermined value, the ignition device and the valve device are operated by a predetermined ignition signal, and the timer means An absorption type refrigerator, characterized in that the ignition signal is invalidated by one output of the voltage detection means.