JPH0450506B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vehicle refrigerator that is cooled by the latent heat of fusion of a cool storage agent.

[Object of the Invention] The present invention provides a vehicle refrigerator in which a cold storage agent is used as a cold heat source and cold air is stirred by an internal fan. , the purpose is to efficiently draw out the limited cold energy available.

[Structure of the Invention] The cold storage type vehicle refrigerator of the present invention incorporates a cooler containing a cold storage agent and a fan that circulates air in the box inside a heat insulating box, and also detects the temperature of the cold storage agent. temperature sensor and turn the fan on high;
It is provided with a changeover switch for weak or stopped operation, and an electric control mechanism for changing over the changeover switch based on a change in the output signal from the temperature sensor.

According to a preferred embodiment of the present invention, when the temperature of the cool storage agent is equal to or higher than the first set temperature, which is slightly higher than its melting temperature, the fan is stopped, and the temperature of the cool storage agent is lowered to the first set temperature. and a second set temperature lower than its melting temperature, the fan operates weakly and the temperature of the refrigerant reaches the second set temperature.
The electric control mechanism is configured such that the fan operates strongly when the temperature is below a set temperature of
Further, a low-temperature refrigerant supply means is incorporated in the cooler, and the fan is operated weakly during the stage of solidifying the refrigerant.

[Effects of the Invention] The cold storage type vehicle refrigerator having the above configuration has the following effects.

(Regarding item 1) The fan is operated strongly at the initial stage of cold storage, when the cold storage agent is completely solidified and stores maximum cold heat, and this cooling state is maintained during the middle stage of cold storage. By operating the fan weakly and stopping it in the later stages of cold storage, the latent heat of melting of the cold storage agent can be released and distributed rationally over time, and the inside of the insulation box can be rapidly cooled in the early stages. ,
A cooling state can be maintained in the middle stage, and waste of battery can be prevented in the latter stage.

Therefore, in a vehicle refrigerator that uses a cold storage agent as a cold heat source and circulates cold air using a fan,
By changing the circulation of cold air inside the insulating box from strong to weak to stopped according to the progress of melting of the cold storage agent, it is possible to efficiently draw out the limited cold energy.

(Regarding item 2) When the temperature of the cool storage agent is below the second set temperature, which is lower than its melting temperature, the fan is operated strongly, and when it is between the first set temperature and the second set temperature, the fan is turned off. The fan is operated weakly, and the fan is stopped when the temperature is higher than the first set temperature.

Therefore, the latent heat of fusion of the cool storage agent can be released and distributed rationally over time, and when the temperature of the cool storage agent is below the second set temperature, the inside of the insulating box is rapidly cooled to the first set temperature. When the temperature is between the second set temperature and the second set temperature, the cooling state can be maintained, and when the temperature is above the first set temperature, battery waste can be prevented.

(Regarding item 3) When a low-temperature refrigerant supply mechanism for cooling the cold storage agent is attached, at the stage of cooling and solidifying the cold storage agent, the fan should be operated weakly to delay the solidification of the cold storage agent as much as possible. At the same time, it is possible to improve the internal cooling capacity.

[Example] Next, a cold storage type vehicle refrigerator of the present invention will be described based on an example shown in the drawings.

In FIG. 1 as a side sectional view of the refrigerator of the present invention and FIG. 2 as a divided perspective view of this refrigerator having a split type structure, a heat insulating box as a housing of the refrigerator is connected to a storage part 1 for refrigerated articles. ,
Storage part 2 of cooler 4 and this cooler storage part 2
A lid body 3 attached via a hinge 5 to the top end of the
The storage part 1 for refrigerated goods consists of a combination of
The storage part 2 of the cooler 4 is box-shaped with one side wall missing, and the storage part 2 of the cooler 4 is missing one side wall and has a top wall surface. It is assembled so that it can be separated by touching the two. The engagement and disengagement between the two can be performed by any known appropriate fastening means. Each of the walls and the lid that make up the heat insulating box has a structure in which a heat insulating board made of hard polyurethane foam or polyethylene foam is sandwiched between hard synthetic resin boards such as ABS resin. A knob 12 is attached to the lid 3 for convenience in opening and closing, and a handle 13 is attached to the refrigerated article storage section 1.

A fan 6 for forced circulation of air inside the refrigerator is attached to a concave portion 3a formed on the inner surface of the lid 3, and its structure and assembly state are shown in FIGS. 3 and 4.

6a is a fan driving motor, and 7 is a mounting bracket thereof. The cooler 4 provided with the air intake/exhaust hole 4b is filled with a cold storage agent 8, such as water in which a freezing point depressant has been dissolved, and preferably uses a low-temperature refrigerant supplied from an on-vehicle refrigerator to conduct heat. A cooling heat exchanger 9 as a medium is built-in. A thermistor 10 for measuring the temperature of the built-in cool storage agent 8 is attached to the outer wall surface of the cooler 4 using an adhesive 11. Further, on the outer wall surface of the cooler 4 facing the refrigerated article storage section 1, a cooling plate 4a made of metal and having a size sufficient to cover the inside cross section is attached to improve heat transfer efficiency. Such a mounting structure is shown in FIGS. 5 and 6.

Since a refrigerator occupies a considerable amount of space in a narrow vehicle interior or trunk space, the refrigerated article storage section 1 is separated from the cooler storage section 2 and taken out of the vehicle so that it does not become a nuisance during seasons when it is not in use. be able to. In that case, by rotating the lid 3 and bringing it to a position where it covers the cooling plate 4a of the cooler housing part 2, you can avoid the inconvenience of the leftover part becoming unsightly, and protect the cooler. is also helpful.

Next, in FIG. 7, which is a side sectional view of the refrigerator showing another embodiment of the present invention, the fan 14 for internal air circulation is not located in the lid 3' but at the lower bottom of the cooler housing part 2. The cooling plate 16 attached to the cooler 15 has ventilation holes a and b provided on both the upper and lower end surfaces, a ventilation hole c that passes through the center of the cooler 15, and a hole left around the cooler 15. The gap d formed between the inner and outer spaces serves as a ventilation path for circulating the air inside the refrigerator, and the cold heat held by the cooler 15 can be more quickly transmitted to the refrigerated articles.

Next, a circuit diagram of an electrical control mechanism for operating strongly, weakly, or stopping the internal air circulation fan 6 of the refrigerator having the above-described structure in accordance with the degree of cold retention of the built-in cold storage agent 8 will be described. In FIG. 8, the drive motor 6a of the fan 6 is powered by the vehicle battery 17, and the temperature detection circuit A of the cool storage agent 8 is connected to the drive motor 6a of the fan 6.
Relays 18, 19 that operate based on signals from
The operating state of the fan is controlled by a fan operation control circuit B consisting of a voltage drop resistor 20 and a voltage lowering resistor 20.

Temperature detection circuit A includes a thermistor 10 and a cold storage agent 8
A low temperature side temperature detection circuit 21 is in charge of a range below a first set temperature, which is slightly higher than the melting temperature of the cold storage agent 8, and a high temperature side temperature detection circuit 22 is in charge of a range above the first set temperature, which is slightly higher than the melting temperature of the cool storage agent 8. Between the battery 17 and the temperature detection circuit A, there is a regenerator solidification mode in which the refrigerant is supplied to the cooling heat exchanger 9 of the regenerator 8, and a regenerator solidification mode in which the refrigerant supply is cut off and the latent heat of fusion of the refrigerant solidified is detected. A use mode changeover switch 23 is provided for switching between the cooling mode to be used and the three states in which the refrigerator is not used. When the electrical contacts a-a' are closed, refrigerant is supplied, and when the b-b' contacts are closed,
The refrigerant supply is cut off, and the refrigerator becomes unusable in the neutral position. 2
4 is a resistor for lowering the voltage supplied to the fan drive motor 6a to cause the fan 6 to operate weakly (low speed).

To explain in more detail the function of the electric circuit for switching the operating state of the refrigerator circulation fan 6 in relation to fluctuations in the temperature of the cold storage agent 8, when the usage mode changeover switch 23 is in the neutral position and the refrigerator is not in use, Then, both the low-temperature detection circuit 21 and the high-temperature detection circuit 22 are forcibly turned off, so that the relays 18 and 19 remain open and the fan drive motor 6a is not energized. When the cold storage agent is partially solidified, that is, at an intermediate temperature between the first set temperature and the second set temperature, the switch 23 is in the cold storage agent solidification mode with contacts a-a' closed, or Under the b-b′ closed cooling mode, the circuit 22 is ON, the relay 19 is closed, and
The battery current is supplied to the motor 6a through the voltage drop resistor 24, and the fan 6 operates weakly (operates at low speed).

When the cold storage agent is completely solidified and the switch 23 closes the contacts a-a' at a temperature below the second set temperature,
Or when contacts b-b' are closed, both circuits 21 and 22 are
Since the relays 18 and 19 are both in the closed position, the battery current is passed directly to the motor 6a, and the fan 6 enters strong operation (high-speed operation).

Next, in Figure 9, which is a diagram showing how this refrigerator works, the amount of change in the variable factors of each component is plotted on the vertical axis, and the passage of time is plotted on the horizontal axis. When 8 is about to melt,
When the use mode selector switch 23 is set to the cold storage agent solidification mode with the a-a' contacts closed, the fan 6 remains stopped and does not work, and the warm air inside the refrigerator is not blown onto the cooling plate 4a, so the cold storage agent is not blown. Rapid cooling of the cold storage agent 8 proceeds without unnecessary dissipation of cold heat for cooling. When the cool storage agent 8 reaches the first set temperature, in this case 3° C., the fan 6 enters a weak operation, and in parallel with the solidification of the cool storage agent 8, cooling inside the refrigerator is promoted. When the cool storage agent 8 is completely solidified and reaches the second set temperature, in this case -4° C., the fan 6 switches to strong operation to powerfully and rapidly cool the inside of the refrigerator. After the inside of the refrigerator reaches a desired low temperature, the operating mode changeover switch 23 switches to the cooling mode in which contacts bb' are closed. At this time, the supply of refrigerant is interrupted, so the temperature of the cool storage agent rises, and when it reaches the second set temperature, in this case -4° C., the fan 6 shifts to weak operation. This is to gradually dissipate the valuable heat stored in the cold storage agent without wasting it.

FIG. 10 is another aspect of the operation time chart regarding each component of the refrigerator shown in FIG. 9.

In this case, after cutting off the supply of cold heat to the regenerator, the cooling mode with a low fan operation is continued for a long time, and when the regenerator is completely melted and its temperature begins to rise rapidly, the Situations are described in which the fan is automatically shut down to prevent wasting battery current.

[Brief explanation of drawings]

FIGS. 1 and 2 are side sectional views and perspective views showing the divided structure of the refrigerator of the present invention, FIGS. 3 and 4 are explanatory diagrams of how an internal circulation fan is attached to the refrigerator lid,
Figures 5 and 6 are diagrams of thermistor installation in the internal cooler, Figure 7 is a sectional side view of the refrigerator as another embodiment, and Figure 8 is a circuit diagram of the electric control mechanism for fan operation. , FIG. 9, and FIG. 10 are time charts showing the relationship between the operations of each component of the refrigerator for two embodiments, respectively. In the figure, 1... Refrigerated article storage part, 2... Cooler storage part, 3... Lid, 4... Cooler, 4a...
Cooling plate, 5...hinge, 6...fan, 6a...
Fan drive motor, 7... Bracket, 8...
... Cold storage agent, 9 ... Heat exchanger, 10 ... Thermistor, 11 ... Adhesive, 17 ... Vehicle battery,
18, 19... Relay, 20, 24... Resistor, 2
1...Low temperature side temperature detection circuit, 22...High temperature side temperature detection circuit, 23...Usage mode changeover switch, A
...Temperature detection circuit, B...Fan operation control circuit.

Claims (1)

[Scope of Claims] 1. A cooler containing a cool storage agent and a fan that circulates air inside the box are installed in a heat insulating box, and a temperature sensor that detects the temperature of the cool storage agent and a fan that circulates the air inside the box are installed. A cold storage type vehicle refrigerator comprising a changeover switch for operating the switch in strong, weak, or stopped operation, and an electric control mechanism for switching the changeover switch based on a change in the output signal from the temperature sensor. 2. When the temperature of the cool storage agent is above the first set temperature, which is slightly higher than its melting temperature, the fan stops, and the temperature of the cool storage agent is set at a second set temperature, which is lower than the first set temperature and its melting temperature. The electric control mechanism is configured such that the fan operates weakly when the temperature is between the set temperature and the fan operates strongly when the temperature of the cool storage agent is below the second set temperature. Claim 1 characterized in that
The cold storage type vehicle refrigerator described in Section 1. 3. The regenerator type according to claim 1 or 2, wherein a low-temperature refrigerant supply means is incorporated in the cooler, and the fan is operated weakly during the stage of solidifying the regenerator. Vehicle refrigerator.