GB2057109A

GB2057109A - Refrigeration system

Info

Publication number: GB2057109A
Application number: GB7928821A
Authority: GB
Original assignee: ZEPHYR KOEL EN LUCHTTECKNIEK B
Current assignee: ZEPHYR KOEL EN LUCHTTECKNIEK B
Priority date: 1979-08-17
Filing date: 1979-08-17
Publication date: 1981-03-25

Abstract

A refrigeration system, in particular for refrigerating a space for cooled transport, comprises a container (1) filled with eutectic liquid or the like, said container housing the sinuous coil (5) of a refrigerant circuit, or primary circuit, and also the sinuous coil of a circuit (4) for a fluid to be refrigerated, or secondary circuit. The secondary circuit includes an air cooler (2) disposed in the space to be refrigerated. According to the invention, the secondary circuit contains a cold carrier in the form of a liquid, and is provided with a pump. <IMAGE>

Description

SPECIFICATION Refrigeration device This invention relates to a refrigeration device, in particular for refrigerating a space for refrigerated transport, comprising a container filled with eutectic liquid or the like, which container houses the sinuous part of a refrigerant circuit, i.e. primary circuit, and also the sinuous part of a fluid circuit, i.e. secondary circuit, to be cooled, said secondary circuit including an air cooler disposed in the space to be refrigerated.

A prior device of this kind is described in Dutch patent application No. 76,01449, which is open to public inspection, and it is an object of the present invention to improve the device.

To this effect, according to the invention, the refrigeration device is characterized in that the secondary circuit, which is provided with a pump, contains a cold carrier in the form of a liquid. In such a device, the place of the relatively heavy container with eutectic liquid can be selected at will. Especially when the refrigeration device is used in a motor-lorry, this if of particular importance with regard to the load on the front and rear axle(s) and with regard to the structural height.

In a further elaboration of the invention, the sinuous part of the secondary circuit can be bypassed by means of a valve by a conduit in which in addition to a valve a heater or like heating device is included. By virtue of this arrangement the air cooler can be defrosted while the sinuous part of the secondary circuit is short-circuited. The result is not only that only a limited part of the cold carrier liquid takes part in the defrosting process, which constitutes an improvement in efficiency, but also that, together with the defrosting process, the eutectic liquid in the container can be refrigerated or frozen, whereby a not inconsiderable saving in time is obtained.

In order that expansion and shrinkage of the liquid in the secondary circuit may be taken up, this circuit is optionally equipped with an expansion tank.

Furthermore, the secondary circuit may be provided with a branch for the supply of a cold carrier, and the circuit may also be equipped with a vent pot.

Furthermore, the primary circuit may be provided with a compressor, a condenser and a buffer vessel for bringing the fluid contained in this circuit at the desired low temperature. Another possibility, however, is for the sinuous part of the primary circuit to be provided with couplings arranged for connection to a refrigerant circuit, filled, for example, with cold brine, and present in some service station. By virtue of that arrangement, the weight of the refrigeration device to be mounted on a motor-lorry is considerably decreased.

One embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings. In said drawings, Fig. 1 is a diagram of the refrigeration device according to the invention; Fig. 2 shows a container filled with a eutectic composition, used in the device shown in Fig. 1; Fig. 3 is a diagram of the air cooler used in the device shown in Fig. 1 with an appurtenant defroster; and Fig. 4 shows a diagrammatic part-sectional side elevation of a motor-lorry provided with the refrigeration device shown in Figs. 1-3.

Referring to the drawings, a refrigeration device comprises a container 1 filled with a eutectic composition, in the present case a liquid, the walls of which container consist of sandwich panels made of polyester (Fig. 2).

Disposed within container 1 are a sinuous part of a conduit 4, forming part of a secondary circuit filled with a cold carrier in the form of a liquid, and a sinuous evaporator part 5 of a condenser 3 (forming part of a primary circuit). To ensure proper heat transfer, the sinuous parts are interconnected by a large number of fins 6.

The primary circuit of condenser 3, which is filled for example with freon, includes between the evaporator part 5 and the condenser a compressor 7 for compressing the vapour coming from evaporator part 5. The discharge end of condenser 3 is connected to a buffer vessel 8, whence liquid can be supplied via a conduit 9 to the inlet end of the evaporator part 5. Conduit 9 is provided with a valve 10 and an expansion valve 11, which controls the supply of liquid to the evaporator part 5, and this depending on the pressure and temperature prevailing in conduit 12 between the evaporator part 5 and compressor 7, the arrangement being such that it is ensured at least, that no liquid enters the compressor.

The freezing or cooling of the eutectic composition in container 1 can be effected, instead of with the condenser 3 with appurtenances described hereinbefore, for example, by pumping a cold brine, from for example a central refrigeration system present in some service station, through the sinuous part. In that case parts 3, 7-12 are omitted, and the ends of the "evaporator part" 5, projecting from container 1 are provided with coupling elements.

Conduit 4, which may be insulated, connects with an air cooler 2, suspended within a space 13 to be refrigerated. The air to be cooled is moved over this air cooler, mounted in space 13 separated by a wall 14, by means of one or more fans 1 5 in the direction indicated by arrows.

The cold carrier liquid is circulated (secondary circuit) by means of a pump 1 6 arranged in the return duct 1 7 from air cooler 2 to the sinuous part of conduit 4 disposed in container 1. Pump 16 is driven by a motor 30. The secondary circuit can be filled through a branch connected to the circuit adjacent to the pump.

As appears from Fig. 3, return duct 1 7 includes a vent pot 1 8 for the removal of air present in the cold carrier.

In order that rime and ice deposited during operation on air cooler 2 (which in Fig. 3 is of different construction from that in the device illustrated in Fig. 1) may be removed, the sinuous part of conduit 4 can be short-circuited by means of a conduit 19 and a magnet valve 20 mounted in conduit 4. Conduit 1 9 includes, in addition to a magnet valve 21, a heater 22, in which the liquid is heated. The expansion of the liquid which thereby occurs, is taken up by an expansion vessel 23. Water dripping off during the removal of the rime and ice is collected in an electrically heated drip tray 24 and discharged to the outside. Parts 16, 18-22 can all be housed in the space enclosed by wall 14.

Fig. 4 shows the diagrammatic arrangement of the refrigeration device of Figs. 1-3 in a motorlorry 25 for refrigerated transport, in which the air circulation is indicated by arrows. The air cooler 2 is mounted on the front wall 27 of the body 26. Mounted under the body is a housing 28 accommodating compressor 7, condenser 3 and buffer vessel 8. Mounted within body 26, against or within the top wall finally, is container 1 , filled with eutectic liquid, unlike the arrangement of Figs. 1 and 2, in which the container 1 is mounted outside the space to be refrigerated, i.e., on top of a top wall 13. As the cold carrier used is a liquid with a forced circulation, container 1 can be mounted at any desired position within the body, so that a proper distribution of the load over the front and rear axles of the lorry can be achieved. Moreover, it will suffice to use conduits all having the same diameter.

Owing to the fact that the sinuous part of conduit 4, which part is contained in container 1, is short-circuited during the defrosting of the device, there is provided a system in which air cooler 2 can be defrosted and the eutectic composition can be cooled or frozen at the same time. By virtue of this, not only is a non-negligible amount of time saved, but in addition the cold liquid present in the sinuous part of conduit 4 and the major part of conduits 4 and 17, as well as the eutectic composition contained in container 1 are not heated.

By virtue of the fact that, as described hereinbefore, the eutectic composition, i.e. the liquid in container 1, can also be frozen by means of cold brine present at a service station, there is provided a refrigeration device having a minimum weight.

Claims

1. A refrigeration device, in particular for refrigerating a space for refrigerated transport, comprising a container filled with eutectic liquid or the like, said container housing the sinuous part of a refrigerant circuit or primary circuit, and also the sinuous part of a circuit or secondary circuit for a fluid to be cooled, said secondary circuit including an air cooler disposed within the space to be refrigerated, characterized in that the secondary circuit (4, 2, 1 7) which is equipped with a pump '(1 6), contains a cold carrier in the form of a liquid.

2. A refrigeration device as claimed in claim 1, characterized in that the sinuous part of the secondary circuit can be short-circuited by means of a valve (20) by a conduit (19) which in addition to a valve (21) includes a heater or like heating device (22).

3. A refrigeration device as claimed in claim 1 or 2, characterized in that the secondary circuit includes an expansion vessel (23).

4. A refrigeration device as claimed in claim 1, 2 or 3, characterized in that the secondary circuit comprises a branch for the supply of a cold carrier, and the circuit also comprises a vent pot (18).

5. A refrigeration circuit as claimed in any of the preceding claims, characterized in that the primary circuit (12, 9) includes a compressor (7), a condenser (3) and a buffer vessel (8).

6. A refrigeration device as claimed in any of claims 1 4, characterized in that the sinuous part of the primary circuit comprises couplings arranged for connection to a cooling fluid circuit.

7. A refrigeration device as claimed in any of the preceding claims, characterized in that the walls of the container (1) consist of sandwich panels.

8. A refrigeration device constructed, arranged, and adapted to operate substantially as described herein with reference to the accompanying drawings.