GB2513901A

GB2513901A - Housings for refrigeration beams

Info

Publication number: GB2513901A
Application number: GB1308420.7A
Authority: GB
Inventors: Peter Maitland Jackson
Original assignee: L E JACKSON COACHWORKS Ltd
Current assignee: L E JACKSON COACHWORKS Ltd
Priority date: 2013-05-10
Filing date: 2013-05-10
Publication date: 2014-11-12
Also published as: GB201308420D0

Abstract

A housing 2 is located within a refrigerated compartment that defines a space to be cooled 4. An array of refrigeration beams 8 for use with a refrigeration apparatus are located within the housing 2 and are adapted to cool air that is circulated between the interior of the housing and the space to be cooled 4. The housing 2 includes a panel 10 that is selectively movable between a first position where it provides an opening 12 in an outer wall of the housing that provides access to the interior of the housing and a second position where it closes the opening. The system preferably is used in the loading space of a vehicle or container. The refrigeration apparatus preferably contains a refrigeration member which may be a refrigeration beam. The refrigeration beam preferably includes first and second pipes within a casing where the space between the pipes and the outer casing includes a phase change material.

Description

TITLE

Housings for refrigeration beams

DESCRIPTION

Technical Field

The present invention relates to an improved housing, particularly for refrigeration beams that can be used as part of a refrigeration apparatus to cool a space.

Background Art

In a lmown refrigeration apparatus, an elongate refrigeration beam is located in a space to be cooled. The space to be cooled can be the interior of a refrigerated compartment such as the loading space of a vehicle body or container. The refrigeration beam typically has a hollow metal or plastic outer casing with metal pipes for carrying a refrigerant gas (such as an HFC or a CFC!HCFC gas) running longitudinally through the interior. The space between the outer surface of the pipes and the inner surface of the outer casing is filled with a phase change material. The phase change material is a freezing mixture that can be formed from a combination of non-toxic salts and organic compounds in an aqueous solution. It can be presented either as a liquid or converted to a gel by using one of a number of different proprietary gelling agents.

An electrically powered condensing unit is used to compress the refrigerant gas which is then passed through the pipes to lower the temperature of the phase change material. Once the temperature of the phase change material has been reduced to below its freezing point (including any margin for super-freezing) the liquid or gel is converted into a solid. Once the flow of refrigerant gas is stopped, the phase change material will eventually start to thaw and return back to a liquid or gel. The temperature of the phase change material will not alter during the change of state (due to the well known principle of latent heat) and the refrigeration beam will therefore remain at a low temperature for a certain period of time during which it will cool the space.

If the refrigeration beam is mounted in the loading space of a transport vehicle, for example, then it is usual for the condensing unit to be operated during the night to reduce the temperature of the phase change material to below its freezing point. The refrigeration beam is then able to cool the loading space when the transport vehicle is used during the daytime. In a typical refrigeration apparatus, a spaced array of refrigeration beams are mounted in the loading space and the metal pipes running longitudinally through the interior of each beam are connected together to form a closcd piping nctwork that is connccted to thc inlct and outlet of thc condcnsing unit.

The refrigeration beam(s) can be located within an insulated housing that is itself located within the space to be cooled. The insulated housing can be fitted to the underside of the roof of the vehicle body or container that defines the refrigeration compartment. The surface temperature of the refrigeration beam(s) will typically be lower than the desired air temperature of the space to be cooled. Air from outside the is housing is moved through the insulated chamber through one or more openings (e.g., by thermostatically operated fans). The air passes over the surface of the refrigeration bcam(s) so that it is cooled bcforc being rc-circulatcd back into the loading spacc.

The applicant has noted that with such an arrangement it is not possible to have access to thc rcfrigcration beam(s) for maintenance or repair. Acccss is typically only possible by removing the housing completely. It will also be appreciated that the refrigeration beam(s) will need to be defrosted periodically to remove any ice that has accumulated on the outer surface. There is therefore a need for an improved housing that addresses these problems.

Summary of the Invention

The present invention provides a housing (typically an insulated housing, which may also be described as an insulated box or plenum chamber) located within a refrigerated compartment that defines a space to be cooled, part of a refrigeration apparatus being locatable within the housing and adapted to cool air that is circulated between the interior of the housing and the space to be cooled, wherein the housing includes a panel that is selectively movable between a first (or open) position where it provides an opening in an outer wall of the housing that provides access to the interior of the housing, and a second (or closed) position where it closes the opening.

In one arrangement the panel is a hinged panel. In other words, the panel is hingedly attached to an outer wall of the housing and can be selectively moved between the first and second positions by a user.

Locking or rctaining mcans can bc providcd to selectively retain the panel in one or both of the first and second positions. For example, locks or catches can be provided to retain the panel in the second (or closed) position so that the opening remains covered when access to the interior of the housing is not required.

Access to the interior of the housing is provided through the opening when the panel is in the first position. The part of the refrigeration apparatus that is optionally locatable within the housing can be, for example, a refrigeration beam, panel or plate that provides radiant cooling. An array of refrigeration beams, panels or plates can be accommodated within the housing depending on the refrigeration apparatus. The housing panel allows access to the refrigeration beam(s), panel(s) or plate(s) for maintenance or repair. The refrigeration beam(s), panel(s) or plate(s) can also be easily defrosted by allowing air at ambient temperature to flow through the opening in the housing.

The housing panel can be any suitable size and shape.

The housing can include a plurality of panels if necessary.

The panel(s) can be provided in a lower (or bottom) wall of the housing.

The present invention frirther provides a refrigerated compartment (e.g., the loading space of a vehicle body or a compartment) that defines a space to be cooled, the refrigerated compartment including a housing as described above.

The housing can be fitted to the underside of an upper wall of the refrigerated compartment.

The present invention further provides a refrigeration apparatus comprising at least one refrigeration member (e.g., one or more refrigeration beams, panels or plates having any suitable shape and construction) located within a housing as described above, and a source of cooling fluid (optionally a refrigeration gas).

A refrigeration beam can include an outer easing, a first pipe for carrying cooling fluid, a second pipe for carrying cooling fluid, and wherein the space between the outer surfaces of the first and second pipes and the inner surface of the outer easing contains a phase change material, wherein the outer casing includes a first areuate section that is shaped to enclose a first substantially cylindrical volume and a second arcuate section that is shaped to enclose a second substantially cylindrical volume, wherein the first and second sections of the outer casing are joined together by rounded arcuate intermediate sections that extend inwards to reduce the amount of space therebetween, wherein the first and second substantially cylindrical volumes are substantially tangent, wherein the first and second pipes are located substantially at a centre of the first and second substantially cylindrical volumes, respectively.

The refrigeration beam can further include a compressible member in the form of a strip of compressible material extending along a longitudinal axis of the refrigeration beam and being located within the space substantially at a centre of the refrigeration beam to accommodate any expansion of the phase change material. The phase change material will typically expand as it freezes. The incorporation of a compressible member within the space can therefore help to eliminate the risk of the refrigeration beam being damaged or fractured by the expansion.

The source of cooling fluid can be a condensing unit, for example.

Drawings Figure 1 is a top view of a housing according to the present invention; Figure 2 is a side view of the housing of Figure 1; and Figure 3 is an end view of the housing of Figure 1 with the panel in an open position.

With reference to Figures 1 to 3, an insulated housing 2 is made of a suitable material such as expanded foam sandwiched between metal or fibreglass laminates and is located with a refrigerated compartment that defines a space 4 to be cooled. The refrigerated compartment can be the loading space of a vehicle body or compartment having an uppcr wall 6 to which the housing 2 is fixcdly mounted or secured.

An array of refrigeration beans S are located within the housing 2. It will be readily appreciated that the panels or plates can also be used in place of the refrigeration beams and that the prescnt invention is equally applicable to other refrigeration members that provide radiant cooling.

The refrigeration beams S are adapted to cool air that is circulated between the interior of the housing 2 and the external space to be cooled 4. For example, air can be moved through the housing 2 by thermostatically controlled fans (not shown). The direction of air flow through the housing 2 is indicated in Figure 1 by the arrows. The cooled air is re-circulated into the refrigerated compartment to cool it.

The housing 2 includes a hinged panel 10 which in this case is defined by the lower wall of the housing. The panel 10 is shown in an open position in Figure 3 and provides an opening 12 through which the interior of the housing 2 can be accessed.

The panel 10 can be selectively moved to a closed position where the opening is covered and where the panel is substantially parallel with the upper wall of the housing 2. The panel 10 can be selectively retained iu the closed position by suitable locks or catches (not shown) which can be provided on one or both of the panel and an adjacent part of the outer wall of the housing. It will be readily appreciated that the panel 10, once open, will remain in the open position under its own weight until it is closed.

To defrost the refrigeration beams 8, the panel 10 can be moved to the open position to allow air at ambient temperature to flow through the opening 12 in the housing 2.

The incoming air will naturally melt any ice that has accumulated on the outer surface of the refrigeration beams 8. The opening 12 can also be used to gain access to the refrigeration beams 8 for routine maintenance or repair.

The refrigeration beams can have any suitable shape or cross-section. However, a particularly suitable construction is described in GB 2432411 and GB 2475882 where the refrigeration beams have a metal or plastics outer easing with two distinct rounded lobes or sections and that are joined together by rounded intermediate sections. When considered along the length of the refrigeration beam, each of the sections and defines a substantially cylindrical volume. A pipe for carrying refrigerant gas supplied by a condensing unit is located in each cylindrical volume. The pipes arc therefore positioned parallel to each other and to a longitudinal axis of the outer casing along the length of the refrigeration beam. The volume between the outer surfaces of the pipe and the inner surface of the outer casing is filled with a phase change material such as a combination of non-toxic salts and organic compounds in an aqueous solution. Compressed refrigerant gas is passed through the pipes from the condensing unit. Such refrigeration beams provide a much more uniform freezing of the phase change material as compared to a conventional refrigeration beam. Forming the outer casing with two distinct rounded sections and has the additional beneficial effect of increasing the surface area of the refrigeration beam that is available for cooling. A strip of compressible, resilient material such as rubber can be supported at the centre of the refrigeration beam. Positioning the strip at the centre of the refrigeration beam means that it is at the meeting point of the two cooling zones which originate at the pipes and can undergo compression at the critical time when substantially all of the phase change material in the cylindrical volumes is frozen and only the phase change material in the intervening regions adjacent the strip remains in the liquid or gel state.

The refrigeration beam is also at its narrowest at this point and may suffer significant stresses as the phase change material expands. These stresses are substantially eliminated by the addition of the strip which is compressed as the surrounding phase change material expands as it freezes.

Claims

CLAIMS1. A housing located within a refrigerated compartment that defines a space to be cooled, part of a refrigeration apparatus being locatable within the housing and adapted to cool air that is circulated between the interior of the housing and the space to be cooled, wherein the housing includes a panel that is selectively movable between a first position where it provides an opening in an outer wall of the housing that provides access to the interior of the housing, and a second position where it closcs the opening.
2. A housing according to claim 1, being an insulated housing.
3. A housing according to claim I or claim 2, wherein the panel is a hinged panel.
4. A housing according to any preceding claim, wherein the panel is provided in a lower wall of the housing.
5. A refrigerated compartment that defines a space to be cooled, the refrigerated compartment including a housing according to any preceding claim.
6. A refrigerated compartment according to claim 5, wherein the housing is fitted to the underside of an upper wall of the refrigerated compartment.
7. A refrigerated compartment according to claim 5 or claim 6, being the loading space of a vehicle body or container.
8. A refrigeration apparatus comprising at least one refrigeration member located within a housing according to any of claims 1 to 4, and a source of cooling fluid.
9. A refrigeration apparatus according to claim 8, wherein the refrigeration mcmbcr is a refrigeration beam comprising an outcr casing, a first pipc for carrying cooling fluid, a second pipe for carrying cooling fluid, and wherein the space between the outer surfaces of the first and second pipes and the inner surface of the outer casing contains a phase change material, wherein the outer casing includes a first arcuate section that is shaped to enclose a first substantially cylindrical volume and a second arcuate section that is shaped to enclose a second substantially cylindrical volume, wherein the first and second sections of the outer casing are joined together by rounded arcuate intermediate sections that extend inwards to reduce the amount of space thcrebetween, wherein the first and second substantially cylindrical volumes are substantially tangent, wherein the first and second pipes are located substantially at a centre of the first and second substantially cylindrical volumes, respectively.
10. A refrigeration apparatus according to claim 9, wherein the refrigeration beam further comprises a compressible member in the form of a strip of compressible material extending along a longitudinal axis of the refrigeration beam and being located within the space substantially at a centre of the refrigeration beam to accommodate any expansion of the phase change material.
11. A refrigeration apparatus according to claim 8 wherein the refrigeration member is a refrigeration panel or plate.
12. A refrigeration apparatus according to claim 11, wherein the refrigeration panel or plate contains a phase change material.
13. A refrigeration apparatus according to any of claims 8 to 12, wherein the source of cooling fluid is a condensing unit.
14. A housing substantially as herein described and with reference to the drawings.