JPH0523206B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has an evaporator dedicated to a refrigerator that is branched from the refrigeration cycle of an automobile air conditioner, and this evaporator performs cooling inside the refrigerator and ice making. This invention relates to a refrigerator for automobiles that obtains functions.

[Prior art] Conventionally, this type of automobile refrigerator
As proposed in Publication No. 45479, etc., both cooling and refrigeration functions are achieved by alternately flowing refrigerant into an air conditioning evaporator and a refrigerator evaporator.

[Problem that the invention seeks to solve]

By the way, in order to increase the capacity of the refrigerator in the above configuration, it is necessary to lengthen the time for the refrigerant to flow into the refrigerator evaporator, but if this time is lengthened, a problem arises in that the cooling capacity is reduced. Therefore, in reality, cooling capacity is usually secured at the expense of refrigerator capacity.

In view of the above points, it is an object of the present invention to improve the capacity of a refrigerator without reducing the cooling capacity.

[Means for solving problems]

In order to achieve the above object, the present invention provides: (a) a refrigerator evaporator installed in parallel with an automobile air conditioning evaporator in a refrigeration cycle; (C) an internal cooling evaporator section provided in the refrigerator evaporator to cool interior air; (d) in the refrigerator evaporator; a freezing evaporator section provided to cool the ice tray; (e) a blower for forcibly circulating air inside the refrigerator to the evaporator section for cooling the refrigerator; and (f) controlling the rotational speed of the blower. (g) increasing the air volume of the blower when the refrigerant is flowing through the refrigerator evaporator, and decreasing the air volume of the blower when the refrigerant is not flowing through the refrigerator evaporator; , and a refrigerator control circuit that controls the valve means and the rotation speed control means in conjunction with each other.

[Effect]

According to the above-mentioned technical means, when the refrigerant does not flow to the evaporator, by increasing or decreasing the air volume of the blower in the refrigerator in response to interruptions in the flow of refrigerant,
Ice making capacity can be increased by suppressing the rise in evaporator temperature. On the other hand, when the refrigerant flows into the evaporator, the air volume is increased to sufficiently cool cans, etc. inside the refrigerator.

〔Example〕

The present invention will be described below with reference to embodiments shown in the drawings. FIG. 1 is a cycle diagram in which a refrigerating evaporator is engaged with a refrigeration cycle for automobile air conditioning, and 10 is a compressor, which is driven by the automobile engine via an electromagnetic clutch 11. 12 is a condenser, 13 is a liquid receiver, 14 is a solenoid valve, 15 is an expansion valve, and 16 is an air conditioning evaporator, which are arranged in the ventilation duct 17 and cool the air blown by the blower 18. This cooling air is blown into the vehicle interior to cool the vehicle interior.

Each of the above devices 10, 12, 13, 14, 1
5, 16 and the piping connecting them constitute an air conditioning refrigeration cycle.

On the other hand, a refrigeration pipe 19 branches from between the liquid receiver 13 and the electromagnetic valve 14, and a constant pressure expansion valve 20, a refrigerator evaporator 21, and a check valve 29 are sequentially connected to this pipe 19 from the upstream side. The downstream end of the pipe 19 joins the outlet pipe section of the air conditioning evaporator 16.
The downstream side of the constant pressure expansion valve 20 has a set pressure (for example,
0.5Kg/cm ² G, evaporation temperature -21℃ for refrigerant R-12
When the pressure drops to a certain level, the valve opens and maintains the set pressure. Further, the evaporator 21 includes an evaporator section 21a for cooling the refrigerator, through which the air inside the refrigerator circulates, and an evaporator section 21b for freezing, which cools the ice tray 22, as in the above-mentioned Japanese Patent Application Laid-Open No. 58-45479. have.
Here, the ice tray 22 and the freezing evaporator section 21b are provided in a freezer compartment 23 that is insulated from the interior space. A refrigerator case 24 is made of resin and has a heat insulating structure, and has a door 24a that can be opened and closed. 25
26 is a resistor for controlling the rotation speed of the blower 25.
It is installed in the duct 27 on the outlet side of the air conditioner and is forcedly air cooled. 28 indicates the canned goods in the refrigerator.

Although the constant pressure expansion valve 20 and the check valve 29 are shown outside the case 24 for convenience of illustration,
Actually, it is installed inside the case 24.

FIG. 2 shows an electric circuit for controlling a refrigerator, where 30 is an on-vehicle battery, 31 is an ignition switch of an automobile engine, and 32 is an electromagnetic clutch 11 of an automobile air conditioner that is energized to operate the compressor 10. A cooling switch 33 is a refrigerator switch, and 34 is a refrigerator control circuit, which controls the energization of the solenoid valve 14 and relays 35 and 36. The control circuit 34 includes a well-known time limit circuit 34a, and the pulse output of the time limit circuit 34a causes the electromagnetic valve 14 and the relay 36 to be energized on and off at predetermined time intervals. Furthermore, to be more specific,
In this example, the pulse output of the time limit circuit 34a cuts off the energization to the solenoid valve 14 for one minute to open the solenoid valve 14, and at the same time cuts off the energization to the relay 36 and connects the movable contact 36a to the contact 36b. Close to the side. When the one minute period has elapsed, the solenoid valve 14 is energized for 15 seconds to close the solenoid valve 14, and the relay 36 is energized to switch the movable contact 36a to the contact 36c side. Thereafter, the solenoid valve 14 is activated at the above-mentioned time intervals by the pulse output of the time limit circuit 34a.
The opening and closing of the relay 36 and the switching of the contacts of the relay 36 are repeated.

Next, the operation of this embodiment in the above configuration will be explained. Now, when the ignition switch 31 of the automobile engine and the cooling switch 32 are turned on and the refrigeration cycle of the automobile air conditioner is operating, when the refrigerator switch 33 is further turned on, power is supplied to the refrigerator control circuit 34. , this control circuit 34 is activated to always energize the relay 35 and keep its contact 35a closed. This results in
The refrigerator blower 25 starts operating. At the same time, a time limit circuit 34a built in the control circuit 34
As described above, the energization of the solenoid valve 14 and the relay 36 is interrupted by the pulse output. When the solenoid valve 14 opens, refrigerant flows into the air conditioning evaporator 16, but the constant pressure expansion valve 2 flows into the refrigerator evaporator 21.
Since valve 0 is closed, refrigerant does not flow. On the other hand, when the electromagnetic valve 14 closes, the flow of refrigerant to the air conditioning evaporator 16 is cut off, so the evaporation pressure of the refrigerator evaporator 21 decreases, and the constant pressure expansion valve 20 opens. As a result, the refrigerant flows into the refrigerator evaporator 21,
The inside of the refrigerator and the ice tray 22 are cooled. Here, the evaporation pressure P in the refrigerator evaporator 21 is
As the solenoid valve 14 opens and closes, the one-dot chain line P ₁ in FIG.
As shown in the figure, it changes. In Figure 3, T ₀
indicates the opening time of the solenoid valve 14 (1 minute in this example), and _T1 indicates the closing time of the solenoid valve 14 (15 seconds in this example). The air volume W of the refrigerator blower 25 is between the contacts 36a and 36 of the relay 36 during _T0 .
b is closed and the resistor 26 is connected in series with the blower 25, so that the amount decreases to W ₀ , while during T ₁ , the contacts 36a and 36c of the relay 36 are closed and the resistor 26 is shorted. Increases to the value of W ₁ . In this way, the air volume W of the refrigerator blower 25 is
By increasing and decreasing in conjunction with the opening and closing of the solenoid valve 14, the following advantages arise.

That is, during T ₀ when the refrigerant is flowing through the air conditioning evaporator 16, by reducing the air volume to W ₀ , the amount of heat exchanged between the indoor air and the refrigeration evaporator part 21a of the refrigerator evaporator 21 is reduced. decreases, the rise in evaporator pressure P ₁ becomes gradual, and therefore evaporator 2
1 temperature rise is suppressed to a low level, and ice making capacity is improved. On the other hand, refrigerant flows into the refrigerator evaporator 21
During T ₁ , the air volume increases to W ₁ , resulting in
The cooling capacity of the air inside the warehouse is increased, and cans 28 and the like can be sufficiently cooled. Even if the air volume increases to _W1 during this _T1 , the temperature of the evaporator 21 does not rise because the refrigerant is flowing through the evaporator 21, and there is no problem.

In Fig. 3, the solid line P ₂ shows the change in evaporation pressure when the air volume is always set to a constant W _1. During T ₀ , the evaporation pressure increases quickly and the ice making capacity decreases. descend.

In addition, in the above-mentioned embodiment, the refrigerator blower 25
Although the rotation speed control means is constructed by the relay 36 and the resistor 26, it goes without saying that the rotation control means can be constructed using various alternative means, such as controlling the voltage applied to the blower 25 by a transistor circuit. be.

In addition to the electromagnetic valve 14, a motor-driven valve, a piezoelectric-driven valve, or the like may be used as the electrically controlled valve means for intermittent refrigerant flow.

〔Effect of the invention〕

As described above, the present invention automatically increases/decreases the air volume of the refrigerator blower in conjunction with the opening/closing of the valve means for intermittent refrigerant flow, thereby improving the refrigerator's performance, especially without causing a decrease in cooling performance. This has a great effect of improving ice making capacity.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a refrigeration cycle diagram, FIG. 2 is an electric circuit diagram, and FIG. 3 is an operation explanatory diagram. 14... Solenoid valve (valve means), 16... Evaporator for air conditioning, 21... Evaporator for refrigerator, 21a... Evaporator section for internal cooling, 21b... Evaporator section for freezing, 2
2... Ice tray, 25... Refrigerator blower, 26...
...Rotational speed control resistor, 34...Refrigerator control circuit.

Claims (1)

[Scope of Claims] 1 (a) A refrigerator evaporator installed in parallel with an automobile air conditioning evaporator in a refrigeration cycle; (b) A refrigerator evaporator installed in the refrigeration cycle and allowing refrigerant to alternately flow through both the evaporators. an electrically controlled valve means; (C) an evaporator section for cooling the refrigerator interior, which is provided in the refrigerator evaporator to cool interior air; and (d) an ice tray cooling tray in the refrigerator evaporator. (e) a blower for forcibly circulating the air inside the refrigerator to the evaporator for cooling the refrigerator; and (f) a rotation speed control means for controlling the rotation speed of the blower. and (g) the valve means so as to increase the air volume of the blower when the refrigerant is flowing to the refrigerator evaporator, and to reduce the air volume of the blower when the refrigerant is not flowing to the refrigerator evaporator. and a refrigerator control circuit that controls rotation speed control means in conjunction with each other.