EP0099108A1

EP0099108A1 - Refrigerator

Info

Publication number: EP0099108A1
Application number: EP83106826A
Authority: EP
Inventors: Masayuki Kikuchi; Kouji Murayama; Hikohisa Arai
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1982-07-14
Filing date: 1983-07-12
Publication date: 1984-01-25
Also published as: JPS5912277A; KR840005543A

Abstract

A refrigerator comprises a cold storage box (2) and a cooling unit (1) both of which may be separated from each other and may be coupled by clamp means (3). The cooling unit (1) are provided with a cold air outlet (26) and a cold air inlet (27) which are, respectively, capable of being sealingly engaged with communication holes (33) and (34) of the cold storage box (2). A cooler (24) of the cooling unit (1) is surrounded by an insulating case (23) except for a motor (25b) for rotating a cold air feeding (25a) fan which serves to forcibly supply cold air to the cold storage box (2). An inverter (8) is provided in the cooling unit (1) so that either alternating current or direct current source may readily be used for the refrigerator.

Description

BACKGROUND OF THE INVENTION

FILED OF THE INVENTION

The present invention relates to a refrigerator for being mounted on automotive vehicles and, more particularly, to a refrigerator with a cold box for storage of substances to be cooled and a cooling unit having a cooling system, in which the cold box and the cooling unit may readily be separated from each other.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

Fig. 1 is a side elevational view of a prior art refrigerator for being mounted on automotive vehicles;
Fig. 2 is a perspective view of a cooling unit of the refrigerator shown in Fig. 1;
Fig. 3 is a plan view of the cold storage box of the refrigerator, showing a state in which the cover of the cold storage box is opened;
Figs 4 through 8 are various views showing one embodiment of the invention;
Fig. 4 is a perspective view of a refrigerator for mounting on automotive vehicles,
Fig. 5 is a perspective view showing a state in which the cooling unit is separated from the refrigerator;
Fig. 6 is a cross-sectional view taken along the line VI-VI of Fig. 5;
Fig. 7 is a cross-sectional view taken along the line VII-VII of Fig. 4; and
Fig. 8 is a circuit diagram for the refrigerator.

DESCRIPTION OF THE PRIOR ART

An automotive refrigerator of the prior art will now be described with reference to Figs. 1 through 3. Fig. 1 shows an entire structure thereof. A cooling unit 51 comprises a condenser 55, a compressor (not shown) and a cooler 54. A cold storage box 52 comprises a box body 56 and an opening/closing cover 57. The cooling unit 51 and the cold storage box 52 are coupled to each other by clamp means 53. By releasing the clamp means, the two units 51 and 52 are separated from each other. The cooling unit 51 separated from the cold storage box 52 is, as shown in Fig. 2, composed of a unit body having the compressor, a radiator and the like and a direct cooling type cooler 54 which is independently formed and is to be located in the cold storage box 52 upon the coupling. The cooler 54 is large in size in the form of an L-shape in cross section, which is substantially the same as the cold storage box 52 in width and height. For use as a refrigerator, the cooling unit 51 is coupled and fixed to the cold storage box 52 so that the cooler 54 is located in a predetermined position in the cold storage box 52, and the cooling unit 51 is operated by a D.C. power (for example, 12V) of the automotive vehicle. With such a construction, in case that the cooler 54 is mounted in the cold storage box 52, the cooling unit 51 which is very heavy as a whole must be lifted after opening the cover 57 of the cold storage box 52 and be inserted into the cold storage box 52 from the upper side. Also in separating the cooling unit from the cold storage box, the opposite operations are required. It is therefore very inconvenient in a restrictive space such as the passenger room of a vehicle and the like. Also, since the cooling of the cold storage box 52 is carried out by a direct cooling with the cooler 54, the interior of the cold storage box 52 is cooled by a natural convection. Therefore, the cooling speed is low and a temperature difference of the storage substance between a part adjacent to the cooler 54 and a part far from the cooler is large; that is, a temperature is varied according to the location of each part of the storage substance. A long period operation is required for making the temperature difference small. Also, it is impossible to cool the cold storage box for a short period of time, particularly for leisure use. Such serious disadvantages are inherent to the refrigerator of the prior art. Furthermore, since the cooler 54 of the cooling unit 51 separated from the cold storage box is exposed to the outside, there is a fear that drops of dew would be leaked or the connecting portion of the cooler 54 would be accidentally damaged. Since the refrigerator is operated only by the D.C. power, in the case that the substances to be cooled are cooled in advance at home, it is disadvantageous that another D.C. power source unit must be used.

SUMMARY OF THE INVENTION

A primary object of the invention is to provide a refrigerator in which a cold storage box may be simply separated from a cooling unit in the lateral direction thereof, the cooling speed is increased and a difference in temperature according to a position of the substance to be cooled is made small without fears that drops of dew would be occur out of a cooler of the cooling unit and that the coupling portion would be damaged after the cooling unit is separated from the cold storage box, and in which either D.C. source or A.C. source may readily be used.
This and other objects of the invention are achieved by providing a refrigerator comprising a cold storage box 2 in which a substance to be cooled is encased, a cooling unit 1 having a refrigerating cycle, and a clamp means 3 for detachably coupling the cold storage box and the cooling unit to each other, the refrigerator being characterized by the cooling unit 1 incorporating a cooler 24, a radiator 30 and a compressor 22, the cooling unit 1 further comprising an insulating case 23 encasing therein the cooler 24 and a fan 25a, communication holes 33 and 34 being provided in a side surface of the cold storage box 2 so as to communicate with a cold air outlet 26 of the insulating case 23 and a cold air inlet 27 thereof, and a cooling system 6 connected to a battery through an inverter 8 for changing D.C. voltage to A.C. voltage and connector terminals 38.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

One embodiment of the invention will now be described with reference to Figs. 4 through 8. A cooling unit 1 comprises means for constituting a refrigerating cycle, air feeding means, controlling means and the like. A cold storage box 2 in which a substance to be cooled is encased is composed of a box body 2a and an opening/closing cover 2b. The cooling unit 1 and the cold storage box 2 are coupled to each other by clamp means 3, and by releasing the clamp means 3, they are separated as shown in Fig. 5. The cooling unit 1 is constructed as follows. An A.C. compressor 22 is mounted on a base 21. A cooler 24 and a fan 25a are surrounded by an insulating case 23 made of insulating material such as foamed stylene resin and urethane resin. The insulating case 23 is mounted on the base 21 with an A.C. motor 25b for feeding air outside the insulating case. An air feeding means 25 is composed of the fan 25a and the motor 25b. An inverter 8 for boosting a D.C. low voltage (for example 12V) to a commertially available power A.C. voltage (for example, 100V) is separated into a signal portion 8a for converting a direct current to an alternating current and an output portion 8b for boosting the voltage and is mounted on an inverted L-shaped mounting plate 8c. The output portion 8b is located on a corner stepped portion 23a of the insulating case 23. A radiator 30 is arranged on the base 21 substantially in the form of a U-shape as viewed from the upper side so as to surround the compressor 22, the insulating case 23 and the invertor 8. A back plate 29 is formed in a U-shape and arranged so as to be connected to free edge portions of the radiator 30. In the insulating case 23, there are formed a cold air outlet 26 and a cold air inlet 27 for forcibly feeding cold air, heat-exchanged in the cooler 24, into the cold storage box 2 by means of the air feeding means 25. The outlet 26 and the inlet 27 are extending from the back plate 29. Annular insulators 29a are attached to the outer periphery of the back plate 29 around the outlet 26 and the inlet 27. On an upper portion of the cooling unit 1, there is provided an upper plate 32 having a grip 31 in the middle portion on the upper surface and couplings 32a and 32b on a front flanged portion and a rear flanged portion. In the cold storage box 2, there are formed communication holes 33 and 34 located in confronting relation with the cold air outlet and inlet 26 and 27 of the cooling unit 1 and communicating therewith upon the coupling. When the cooling unit 1 is coupled to the cold storage box 2, cylindrical portions of the cold air outlet 26 and inlet 27 are engaged with the communication holes 33 and 34 of the cold storage box 2 and the adjacent portions to the engagements are sealed by compression of the annular insulators 29a attached to the back plate 29. Insulating caps 35 and 36 are mounted on the communication passages 33 and 34 for preventing leakage of cooling air from the cold storage box 2 in the case that the cold storage box 2 cooled by the cooling unit 1 is used independently of the cooling unit 1. In Fig. 5, one insulating cap 35 is mountd on the hole 33. Upon cooling in a normal operation, the insulating caps 35 and 36 are to be received in receiving portions 35a and 36a. Reference numeral 37 denotes a shoulder belt.
Fig. 8 shows a power supply circuit for the automotive refrigerator. The inverter circuit 5 functions to convert into an A.C. commertial voltage (e.g., 100V) a supply voltage inputted to terminals a and b from a D.C. power (e.g., 24V) of a truck, a bus, a cruiser and the like or a D.C. power (e.g., 12V) of a passenger car while boosting the latter voltage. The invertor circuit is adapted to be connected to the refrigerating system 6 through conector terminals 38. On the other hand, power terminals c and d of commertially available A.C. voltage (e.g., 100V) are connected to the refrigerating system 6 through the conector terminals 38.
With such a construction, the cold air is fed through the cold air outlet 26 into the cold storage box 2 by the fan 25a of the air feeding means 25 to thereby cool the substance. The cold air used for cooling the substance is returned from the cold air inlet 27 back to the cooler 24 and is cooled again. Thus, since the cooling unit 1 serves to forcibly recirculate the cold air obtained through the refrigerating cycle, the cooling speed of the substance in the cold storage box 2 is high in comparison with a conventional convection type refrigerator and a temperature difference according to the position of the substance may be made small. Furthermore, since only the fan 25a of the air feed means 25 is encased in the insulating case 23 surrounding the cooler 24 and the motor 25b for air feeding is disposed outside of the insulating case 23, the invasion of heat from the outside is small to enhance the efficiency. Also, in the coupling between the cooling unit 1 and the cold storage box 2, since the cylindrical portions of the cold air outlet 26 and inlet 27 of the cooling unit 1 are engaged with the communication holes 33 and 34 of the cold storage box 2 in the lateral direction and then, the coupling therebetween is locked by the clamp means 3, the manual operation therefor may be extremely simplified. In this case, the coupling portions between the cooling unit 1 and the cold storage box 2 are sealed by the insulators 29a, the leakage of cold air therefrom is very small. Moreover, when after cooling the substance, the clamp means 3 is released and the cooling unit 1 is separated from the cooling unit 2, the cooler 24 is not exposed outside. The leakage of dew may be prevented and the damage of the cooler 24 may be also prevented. In case that the cold storage box 2 separated from the cooling unit 1 is carried, by mounting the insulating caps 35 and 36 on the communication holes 33 and 34 of the cold storage box 2, the leakage of cold air may be prevented. Also in this case, the ability to keep cold the cold storage box 2 is improved. On the other hand, since the electric energy is supplied from the terminals a and b for the D.C. power of the automotive vehicle or the like and it is converted into the commertially available A.C. voltage through the inverter circuit 5 and supplied to the refrigerating system 6 for the commertial voltage, or otherwise the electric energy may readily be supplied from the power terminals c and d for the domestic A.C. voltage by simply changing over the connector terminals 38, the refrigerator is very convenient for both D.C. and A.C. operations. In addition, the A.C. commertial voltage may be supplied to the refrigerating system 6. Therefore, it is unnecessary to employ and manufacture specifically designed compressor and air feeding motor for the refrigerating system instruments for general use may be used in the refrigerating system.
As described above, according to the present invention, since without lifting the cooling unit, the cold storage box may be separated simply in the lateral direction apart from the cooling unit, it is very easy to handle the refrigerator. Also, since the cold air is forcibly recirculated in the cold storage box, the cooling speed is extremely increased so that the temperature difference according to the positions of the substance to be cooled may be reduced. Furthermore, since the cooler is not exposed outside, there is no fear that the dew would be leaked to the outside and the coupling portions would be damaged. Furthermore, since the refrigerator may readily be operated by either D.C. source or A.C. source, generally designed A.C. power instruments may be used in the cooling system.

Claims

1. A refrigerator comprising a cold storage box (2) in which a substance to be cooled is encased, a cooling unit (1) having a refrigerating cycle, and a clamp (3) means for detachably coupling said cold storage box and said cooling unit to each other: carac- terized by said cooling unit (1) incorporating a cooler (24), a radiator (30) and a compressor (22); said cooling unit (1) further comprising an insulating case (23) encasing therein said cooler (24) and a cold air feeding fan (25a); communication holes (33) and (34) being provided in a side surface of said cold storage box (2) so as to communicate with a cold air outlet (26) and a cold air inlet (27) of said insulating case (23); and a cooling system (6) connected to a power source through an inverter (8) for converting a D.C. voltage to an A.C. voltage and connector terminals (38).

2. A refrigerator as claimed in claim 1, said cooling unit 1 further including a motor (25b) for said cold air feeding fan (25a), said motor being disposed outside of said insulating case (23).

3. A refrigerator as claimed in claim 1, wherein said cold air outlet (26) and said cold air inlet (27) of said cooling unit (1) are engaged with said communication holes (33) and (34) of said cold storage box (2), and insulators (29a) are interposed at the coupling portions between said cooling unit (1) and said cold storage box (2).

4. A refrigerator as claimed in claim 1, wherein said inverter (8) is composed of separate components of a signal portion (8a) for converting a direct current to an alternating current and an outlet portion (8b) for boosting a voltage.