GB2432202A

GB2432202A - Vented apparatus for housing electronic equipment

Info

Publication number: GB2432202A
Application number: GB0523248A
Authority: GB
Inventors: John Lougart; Bent Ove Andersen; Kim Lasota
Original assignee: Motorola Inc
Current assignee: Motorola Solutions Inc
Priority date: 2005-11-15
Filing date: 2005-11-15
Publication date: 2007-05-16
Anticipated expiration: 2025-11-15
Also published as: WO2007059425A2; WO2007059425A3; GB0523248D0; TW200730068A; GB2432202B; TWI301742B

Abstract

A container 103 housed within a cabinet 101 and at least one passage (421, 423, fig 4) adapted to allow air to flow between the cabinet and the container and at least one passage (425, 427, fig 4) adapted to allow air to flow between the container and the cabinet. The apparatus may include a plurality of inner containers 103, 105 stacked inside the cabinet 101 and arranged to allow air to enter both of the containers from at least one of the passages (421, 423 fig 4) and to allow air to leave both of the containers into at least another one of the passages (425, 427 fig 4) especially see figure 3.

Description

1 2432202 TITLE: APPARATUS FOR HOUSING ELECTRONIC EQUIPMENT

FIELD OF THE INVENTION

This invention relates to apparatus for housing electronic equipment. In particular, the invention relates to apparatus which facilitates cooling of electronic equipment housed thereby.

BACKGROUND OF THE INVENTION

Some electronic and electrical equipment generates considerable heat in use and an arrangement is needed to remove the heat to leave the equipment at a safe operating temperature. A base transceiver station as used in a mobile communications network provides an example of such equipment. Such a station typically comprises a housing in which is contained electrical and electronic equipment in the form of various interconnected modules which carry out the various functions of the station. The equipment may consist of modules that have different power dissipation rates and different sensitivities to ambient temperature. In general, the modules may be considered to consist of high power modules and low power modules depending on their power dissipation rate. Usually, the high power modules will be designed to operate at an ambient temperature that results from the heating of the air around them by their power dissipation. If the low power modules are also tolerant to a similar ambient temperature the high power and low power modules may be 2 CMO8532/GB/JM housed together in the same housing. However if any of the low power modules have a high sensitivity to ambient temperature this simple arrangement is not possible.

One well known way of dealing with this problem is to apply fans to cool the high power modules and arrange the airflow from the high power modules so the hot air is led out of the housing and is not used to cool the lower power modules. However the fans have a finite lifetime and it is necessary to monitor the conditions inside the housing to check that the fans are working properly. Also, when the fans have an operating fault, it is necessary to close down the station so that the fan(s) may be serviced or replaced.

US 3874444 describes an apparatus which allows heat to be removed from equipment racks held in the apparatus. Separation is maintained between airflows in upper and lower sections of the equipment. The apparatus does not provide an enclosed housing for the equipment and does not allow maximum cooling efficiency to be obtained because coolant air is delivered only on one side of the apparatus.

SUMMARY OF THE INVENTION

According to the present invention in a first aspect there is provided apparatus for housing electronic equipment including an outer cabinet, an inner container inside the cabinet, a plurality of enclosed air passages between the cabinet and the container, the cabinet having a plurality of cabinet vents adapted to allow air to enter and/or leave each of fl 3 CM08532/GB/DJM the passages, the container having a plurality of container vents including a first container vent adapted to allow air to enter the container from one of the passages and a second container vent adapted to allow air to leave the container into another one of the passages.

The container vents may further include a third container vent adapted to allow air to enter the container from a third one of the passages and a fourth container vent adapted to allow air to leave the container into a fourth one of the passages. The first and third passages may conveniently be adjacent to one another and the second and fourth passages may be adjacent to one another.

The apparatus may advantageously include a plurality of inner containers stacked vertically inside the outer cabinet. The inner containers may thus include a first inner container and a second inner container, wherein the first inner container has a first plurality of container vents adapted to allow air to enter the container from a first one of the passages and to leave the container into a second one of the passages and wherein the second inner container has a second plurality of container vents adapted to allow air to enter the container from the first one of the passages and to leave the container into the second one of the passages. The first plurality of container vents may further include a third container vent adapted to allow air to enter the first inner container from a third one of the passages and a fourth container vent adapted to allow air to leave the first inner container into a 4 CM08532/GJ3IDJM fourth one of the passages, and the second plurality of container vents may further include a third container vent adapted to allow air to enter the second inner container from a third one of the passages and a fourth container vent adapted to allow air to leave the second inner container into a fourth one of the passages.

In the apparatus, the inner container or each of the inner containers may be closed, except at its container vents, and may have at least four side faces and the container vents may conveniently be provided in the side faces. The outer cabinet and the inner container or containers may for example be box shaped.

The inner container or each of the inner containers of the apparatus may conveniently include electronic equipment modules which are stacked with vertically extending gaps between them to allow air to flow upwardly, e.g. vertically upwardly, between the modules to withdraw heat from the modules.

When the apparatus is in use, the passages may suitably extend substantially vertically so that air may rise vertically upward therein.

The apparatus may include partitions inside the outer cabinet between the cabinet and the inner container or containers and the passages may suitably be formed between the partitions.

Where the outer cabinet and the inner container or containers of the apparatus are box shaped, the partitions may extend between inner corners of the cabinet and outer corners of the inner container or containers.

CM08532/G13/DJM A particular preferred form of the apparatus may include four passages. The outer cabinet may include a first cabinet vent adapted to allow air to enter a first one of the passages and a second cabinet vent adapted to allow air to leave the first one of the passages. The outer cabinet may also include a third cabinet vent adapted to allow air to enter a second one of the passages and a fourth cabinet vent adapted to allow air to leave the second one of the passages. The outer cabinet may also include a fifth cabinet vent adapted to allow air to enter a third one of the passages and a sixth cabinet vent adapted to allow air to leave the third one of the passages. The outer cabinet may also include a seventh cabinet vent adapted to allow air to enter a fourth one of the passages and an eighth cabinet vent adapted to allow air to leave the fourth one of the passages.

The outer cabinet may include at least one plate or panel which seals one of the passages.

The outer cabinet may have at least four side faces and may be adapted to receive in each of its side faces a removable plate or panel. The plate or panel may be attached one of a number of well known ways. For example, the plate may have a hinge on one side (near one side edge of the front face), and a fastener such as a screw or lock on the other side. It can also be fixed in place using removable fasteners only, such as screws or rivets. It can also be push fitted or click fitted to be held in position.

The plate or panel may be either of a first kind which has at least one of the cabinet vents or of a

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6 CM08532/GB/DJM second kind which is without vents to seal one of the passages, at least two of the plates being of the first kind. Each of the plates of the first kind when fitted in a side face of the outer cabinet provides a cabinet vent which may conveniently face a corresponding container vent of an inner container. Where a removable plate is not without vents it is preferred that the plate has both a lower vent and an upper vent for simplicity and convenience in use, as exemplified later.

According to the present invention in a second aspect there is provided a closed container for use as an inner container in the apparatus according to the first aspect, the container having a plurality of vents including a first inlet vent in a first side face of the container, a second inlet vent in a second side face of the container, a first outlet vent in a third side face of the container and a second outlet vent in a fourth side face of the container, wherein the first and second side faces are adjacent to one another and have a common corner and the third and fourth side faces are adjacent to one another and have a common corner. The container may include electronic equipment modules therein which are stacked with vertically extending gaps between them to allow air to flow upwardly between the modules to withdraw heat from the modules, wherein the inlet vents of the container are formed in the first and second side faces at a height not above the bottom of the modules and the outlet vents are formed in the third and fourth side faces at a height not below the top of the modules. n

7 CM08532/GB/DJM Further features of the invention are as disclosed in the embodiments of the invention to be described and benefits of the invention are illustrated later with reference to such embodiments.

Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of apparatus embodying the invention for housing electronic equipment.

FIG. 2 is a perspective view of an inner container included in the apparatus of FIG. 1.

FIG. 3 is a perspective view of stacked inner containers included in the apparatus of FIG. 1.

FIG. 4 is a cross-sectional plan view of the apparatus of FIG. 1.

FIG. 5 is a front view of a plate for use with an outer cabinet of the apparatus of FIG. 1.

FIG. 6 is a front view of an alternative plate for use with an outer cabinet of the apparatus of FIG. 1.

FIG. 7 is a front view of an alternative plate for use with an outer cabinet of the apparatus of FIG. 1.

FIG. 8 is a front view of an alternative plate for use with an outer cabinet of the apparatus of FIG. 1.

FIG. 9 is a front view of an alternative form of vent for use in the apparatus of FIG. 1.

FIG. 10 is a front view of an alternative form of vent for use in the apparatus of FIG. 1.

8 CM08532/GB/DJM FIG. 11 is a front view of an alternative form of vent for use in the apparatus of FIG. 1.

FIG. 12 is a front view of an alternative form of vent for use in the apparatus of FIG. 1.

DESCRIpTION OF EMBODIMENTS OF THE INVENTION

FIG. 1 is a perspective view of apparatus 100 embodying the invention for housing electronic equipment. The apparatus 100 includes an outer box shaped cabinet 101 and, fitted inside the cabinet 101, an upper box shaped inner container 103 stacked on top of an identical lower box shaped inner container 105.

The container 103 includes a container vent 117 in the form of a horizontal rectangular slot. The container 105 includes a similar vent 119. The containers 103 and 105 are described in more detail later with reference to FIGS. 2 and 3.

The outer cabinet 101 includes a horizontal top face 107 and a horizontal base 109 and has four vertical side faces extending between the top face 107 and the base 109. Each of the side faces of the cabinet 101 is adapted to receive a removable plate. The removable plates may take various forms as described later with reference to FIGS. 5 to 8. In FIG. 1, a plate having a form 500 is shown fitted in one of the side faces of the cabinet 101. The plate of form 500 includes an upper cabinet vent 501 and a lower cabinet vent 503. In FIG. 1, a plate which covers another one of the side faces of the cabinet 101 (a side face to the left of the plate n 9 CM08532/GBIDJM 111 as shown) has been removed allowing the containers 103 and 105 to be seen.

FIG. 2 is a perspective view of the inner container 103 showing more detail of the inner container 103. The inner container 103 is a box shaped structure having a horizontal top face 201 and a horizontal bottom face 203 and four vertical side faces 205, 207, 221 and 223 (the side faces 221 and 223 are not shown in FIG. 2 but are shown in FIG. 4) . The inner container 103 is closed on all faces apart from container vents formed in each of the side faces of the container 103. The side face 205 includes near its bottom edge (its edge adjacent to the bottom face 203) the vent 117 already seen in FIG. 1.

The side face 207 includes near its bottom edge a vent 209 (through which is seen an inner surface of the bottom face 203) . The vent 209 is similar to the vent 117. The side face of the container 103 which is opposite the side face 205 (i.e. the side face 221 shown in FIG. 4) includes a vent 211 as indicated by a dashed line in FIG. 2. Similarly, the side face of the container 103 which is opposite the side face 207 (i.e. the side face 223 shown in FIG. 4) includes a vent 213 as indicated by a dashed line in FIG. 2. The vents 211 and 213 are in the form of horizontal rectangular slots near the top edge of the respective side faces in which they are formed, i.e. near the edges joining the top face 201.

The inner container 103 houses electronic equipment modules 215, 217 and 219. The modules 215, 217 and 219 are arranged so that coolant air can flow between them and between the modules 215, 217 and 219 and the side n CM08532/GBIDJM faces of the inner container 103. In use, with the electronic modules 215, 217 and 219 operational and producing heat, cool air flows into the container 103 via both of the vents 117 and 209, which serve as dual air inlet container vents for the container 103. The air may flow into the container 103 via the inlet vents 117 and 119 by simple convection. Alternatively, or in addition the air may be blown or drawn by a fan, pump or similar known device (not shown) located internally or externally to the container 103 (and internally or externally to the cabinet 101) . The air in the container 103 flows upwardly between the individual modules 215, 217 and 219 and between the modules 215, 217 and 219 and the side faces of the container 103 thereby carrying heat from the modules 215, 217 and 219. The heated air leaves the inner container 103 via the vents 211 and 213 which thereby serve as dual outlet container vents of the container 103.

The positions in the appropriate side faces of the container 103 of the inlet container vents 117 and 209 and of the outlet container vents 211 and 213 depends on heat flows obtained in use in the container 103. The positions may be optimised by carrying out simulation experiments or experiments using a development container. The inlet container vents 117 and 209 may be positioned at a height which is not above the bottom of the electronic equipment modules 215, 217 and 219 when housed in the container 103. Furthermore, the outlet container vents 211 and 213 may be positioned at a height which is not below the top of the electronic equipment modules 215, 217 and 219 when housed in the 11 CM08532/GB/DJM container 103. If the container 103 is considered to have a height h measured between the top face 201 and the bottom face 203, the upper edge of the inlet container vents 117 and 209 is preferably provided at a distance not greater than 0.2h from the (outer surface of) the bottom face 103. Similarly, the lower edge of the outlet container vents 211 and 213 is preferably provided at a distance not greater than 0.2h from the (outer surface of) the top face 201.

FIG. 3 shows the inner container 103 stacked on top of the inner container 105 in the same manner as in FIG. 1. The inner containers 103 and 105 are identical in construction, and the inner container 105 includes the container vent 119 shown in FIG. 1 and further container vents 301, 303 and 305. The vents 119, 301, 303 and 305 of the container 105 are the same as the vents 117, 209, 211 and 213 of the container 103 respectively. The vents 119 and 301 of the container 105 are respectively dual container inlet vents beneath the vents 117 and 209 of the container 103, and the vents 303 and 305 are dual container outlet vents respectively beneath the vents 211 and 213 of the container 103. In use, cool air applied to the container 103 via the inlet vents 117 and 209 is also applied to the container 105 via the inlet vents 119 and 301. Heated air leaves the outlet vents 303 and 305 of the container 105 as well as from the outlet vents 211 and 213 of the container 103.

FIG. 4 is a cross-sectional plan view of the apparatus 100 of FIG. 1 as seen on a plane indicated by the line 4-4 in FIG. 1. In FIG. 4, all side faces of the cabinet 101 are shown and these are indicated by 12 CM08532/GB/DJM reference numerals 403, 405, 407 and 409 respectively.

All side faces of the container 103 are also shown and these are indicated by reference numerals 205, 207, 221 and 223 respectively. A Y shaped partition 411 extends from the internal corner at the junction between the side faces 403 and 405 of the cabinet 101. The external corner formed between the side faces 205 and 207 of the container 103 fits in the space between the arms of the Y of the partition 411. A Y shaped partition 413 extends from the internal corner at the junction between the side faces 405 and 407 of the cabinet 101. The external corner formed between the side faces 207 and 221 of the container 103 fits in the space between the arms of the Y of the partition 413. A Y shaped partition 415 extends from the internal corner at the junction between the side faces 407 and 409 of the cabinet 101. The external corner formed between the side faces 221 and 223 of the container 103 fits in the space between the arms of the Y of the partition 415. A Y shaped partition 417 extends from the internal corner at the junction between the side faces 403 and 409 of the cabinet 101. The external corner formed between the side faces 205 and 223 of the container 103 fits in the space between the arms of the Y of the partition 417.

The partitions 411, 413, 415 and 417 are vertically extending between the cabinet 101 and the container 103 inside it. Four separated vertically extending passages or chimneys 421, 423, 425 and 427 are thereby formed between each pair of the partitions 411, 413, 415 and 417 and between the outer cabinet 101 and the inner container 103. The passages 421, 423, 425 and 427 also 13 CM08532/GBIDJM extend between the outer cabinet 101 and the lower inner container 105.

Each of the side faces 403, 405, 407 and 409 may receive a removable plate having one of four possible forms shown In FIGS. 5 to 8. In a first form 500 of the removable plate shown in FIG. 5 (and already seen fitted in a side face of the cabinet 101 in FIG. 1), the removable plate includes an upper cabinet vent 501 in the form of a horizontally extending rectangular slot near the top of the plate and a lower cabinet vent 503 in the form of a horizontally extending rectangular slot near the bottom of the plate. Alternatively, in a second form 600 of the removable plate shown in FIG. 6, the plate includes only the upper cabinet vent 501.

Alternatively, in a third form 700 of the removable plate shown in FIG. 7 (which is the inverse of the form 600), the plate includes only the lower cabinet vent 503. Alternatively, in a fourth form 800 of the removable plate shown in FIG. 8, the plate is without any vents.

Normal use of the apparatus 100 is as follows. Two of the passages 421, 423, 425 and 427 serve as air inlet passages, and the other two of the passages 421, 423, 425 and 427 serve as air outlet passages. Removable plates of the form 500 shown in FIG. 5 are fitted in each of the side faces 403, 405, 407 and 409 of the outer cabinet 101. The lower cabinet vent 503 of the plate of the form 500 which is fitted in the side face 403 of the cabinet 101 thereby faces (i.e. is level with) the container vent 119 of the container 105. The lower cabinet vent 503 of the plate of the form 500

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14 CM085 32/GB/DiM which is fitted in the side face 405 of the cabinet 101 thereby faces the container vent 301 of the container 105. The upper cabinet vent 501 of the plate of the form 500 which is fitted in the side face 407 of the cabinet 101 thereby faces the container vent 211 of the container 103. The upper cabinet vent 501 of the plate the form 500 which is fitted in the side face 409 of the cabinet 101 thereby faces the vent 213 of the container 103. Cool air flows through the lower cabinet vents 503 in the plates of form 500 fitted in the side faces 403 and 405 of the cabinet 101. The cool air thereby enters the passages 421 and 423. The cool air in the passages 421 and 423 flows through the lower or inlet container vents 119 and 301 of the container 105 into the interior of the container 105. The cool air in the passages 421 and 423 also flows through the lower or inlet container vents 117 and 209 of the container 103 into the interior of the container 103.

Air heated by the electronic equipment modules 215, 217 and 219 leaves the container 103 via the upper or outlet container vents 211 and 213 of the container 103 and thereby enters the passages 425 and 427. Likewise, air heated by similar electronic equipment components (not shown) in the container 105 leaves the container 105 via the upper or outlet container vents 305 and 303 of the container 105 and thereby also enters the passages 425 and 427. The heated air in the passages 425 and 427 from the container vents 303 and 305 rises in the passages 425 and 427. Heated air in the passages 425 and 427 leaves the passages 425 and 427 via the upper cabinet vents 501 on the plates of form 500 fitted in 1 5 CM08532/GBIDJM the side faces 407 and 409 of the cabinet 101 respectively and thereby leaves the apparatus 100.

In an alternative way of using removable plates in the apparatus 100, a plate of the form 600 is fitted in the side faces 407 and 409 adjacent to the air outlet passages 425 and 427. The upper cabinet vents 501 of the plate face the upper container vents 211 and 213 of the container 103. Furthermore, a plate of the form 700 is fitted in the side faces 403 and 405 adjacent to the air inlet passages 421 and 423, the lower cabinet vents 503 of the plate facing the lower container vents 119 and 301 of the container 105.

In a further alternative way of using the apparatus 100, one or two of the side faces 403, 405, 407 and 409 of the cabinet 101 may be fitted with a plate of the form 800 as shown in FIG. 8. In this case, one of the two remaining passages is used to deliver cool air and the other of the remaining passages is used to remove heated air. Thus, the side faces remaining (after two are fitted with plates of the form 800) are preferably both fitted with a plate of the form 500 or one is fitted with a plate of the form 600 and the other is fitted with a plate of the form 700 as appropriate.

Thus, for example, if the side faces 405 and 409 of the cabinet 101 are closed with a plate of the form 800, the side faces 403 and 407 are both fitted with a plate of the form 500, or the side face 403 is fitted with a plate of the form 700 and the side face 407 is fitted with a plate of the form 600. The passage 421 in each case thereby serves as a passage for delivery of cool air and the passage 425 in each case serves as a passage 16 CM08532/GBIDJM for removal of heated air. Similarly, for example, if the side faces 403 and 407 of the cabinet 101 are closed with a plate of the form 800, the side faces 405 and 409 are both fitted with a plate of the form 500 or the side face 405 is fitted with a plate of the form 700 and the side face 409 is fitted with a plate of the form 600.

The passage 423 thereby serves in each case as a passage for delivery of cool air and the passage 427 serves in each case as a passage for removal of heated air.

The plates of the forms 500, 600, 700 and 800 may be attached to the side faces of the cabinet 101 in one of a number of well known ways. For example, the plate may have a hinge on one side (near one side edge of the front face), and a fastener such as a screw or lock on the other side. It can also be fixed in place using removable fasteners only, such as screws or rivets. It can also be push fitted or click fitted to be held in position.

The container vents provided in the containers 103 and 105 and the cabinet vents provided in the plates of the forms 500, 600 or 700 fitted in the side faces of the cabinet 101 in the embodiments of the invention described above are all elongate rectangular slots. In further embodiments of the invention, alternative vent forms may be used for any one or more of the container vents or the cabinet vents. Examples of further vent forms are shown in FIGS. 9 to 12. In an alternative vent form 900 shown in FIG. 9, the vent is in the form of an elongate oval slot. In an alternative vent form 1000 shown in FIG. 10, the vent is in the form of an elongate elliptical slot. In an alternative vent form 1100 shown 17 CM08532/GBIDJM in FIG. 11, the vent is in the form of multiple side by side elongate slots. These slots are shown as rectangular but they could be of another form, e.g. similar to the form 900 or the form 1000. In an alternative vent form 1200 shown in FIG. 12, the vent is in the form of multiple elongate slots one above the other. These slots are shown as rectangular but they could be of another form, e.g. similar to the form 900 or the form 1000. In another alternative form of the vent (not shown), the vent may be a grille or grating comprising a multiplicity of small holes formed between intersecting ribs, e.g. arranged in rows and columns.

By use of the apparatus 100, electronic equipment may be securely housed in an enclosed housing and may be efficiently kept cool in operation, particularly for example by providing coolant air inlets on at least two side faces of the outer cabinet 101 and air outlets on at least two other side faces of the outer cabinet 101, thereby separating flows of cool air and heated air.

Furthermore, use of the apparatus 100 is very flexible and convenient in that one or twoside faces of the outer cabinet 101 and the passages adjacent to those faces need not be used and may conveniently be sealed with a plate or panel having no vents. This provides a very convenient form of the apparatus 100 where the apparatus has to be operated next to a wall or a corner between two walls.

Another benefit of the apparatus 100 is that it allows electronic equipment modules to be housed in a plurality of inner containers, namely the container 103 and the container 105, and kept cool within the same 18 CM08532/GBIDJM outer cabinet 101. Vertical stacking of the containers 103 and 105 is beneficial to minimise the amount of floor space occupied by the apparatus 100. The modules in the respective containers 103 and 105 may have similar or different power dissipation rates and, where the power dissipation rates are different, the modules are conveniently separated into the containers 103 and 105. The apparatus 100 allows cool air to be delivered to the upper container 103 as well as to the lower container 105 without being pre-heated in the lower container 105 before it reaches the upper container 105.

The apparatus 100 may avoid the use of fans, pumps and other known serviceable devices to deliver the coolant air, which is beneficial in avoiding loss of operating time when such devices break down and/or have to be serviced. However, use of such devices may optionally be made if desired to assist delivery and removal of coolant air. )

Claims

19 CM08532/GBIDJM

CLAIMS

1. Apparatus for housing electronic equipment including an outer cabinet, an inner container inside the cabinet, a plurality of enclosed air passages between the cabinet and the container, the cabinet having a plurality of cabinet vents adapted to allow air to enter and/or leave each of the passages, the container having a plurality of container vents including a first container vent adapted to allow air to enter the container from one of the passages and a second container vent adapted to allow air to leave the container into another one of the passages.

2. Apparatus according to claim 1 wherein the container vents further include a third container vent adapted to allow air to enter the container from a third one of the passages and a fourth container vent adapted to allow air to leave the container into a fourth one of the passages.

3. Apparatus according to claim 2 wherein the first and third passages are adjacent to one another and the second and fourth passages are adjacent to one another.

4. Apparatus according to claim 1 including a plurality of inner containers stacked vertically inside the outer cabinet.

5. Apparatus according to claim 4 including a first inner container and a second inner container, wherein the first inner container has a first plurality of container vents adapted to allow air to enter the container from a first one of the passages and to leave CM08532/GB/DJM the container into a second one of the passages and the second inner container has a second plurality of container vents adapted to allow air to enter the container from the first one of the passages and to leave the container into the second one of the passages.

6. Apparatus according to claim 5 wherein the first plurality of container vents further includes a third container vent adapted to allow air to enter the first inner container from a third one of the passages and a fourth container vent adapted to allow air to leave the first inner container into a fourth one of the passages and wherein the second plurality of container vents further include a third container vent adapted to allow air to enter the second inner container from a third one of the passages and a fourth container vent adapted to allow air to leave the second inner container into a fourth one of the passages.

7. Apparatus according to any one of the preceding claims wherein the inner container or each of the inner containers is closed, except at its container vents, and has at least four side faces and the container vents are provided in the side faces.

8. Apparatus according to claim 7 wherein the outer cabinet and the inner container or containers are box shaped.

9. Apparatus according to any one of the preceding claims wherein the inner container or each of the inner containers includes electronic equipment modules which are stacked with vertically extending gaps between them to allow air to flow upwardly between the modules to withdraw heat from the modules.

21 CM08532/GBIDJM 10. Apparatus according to any one of the preceding claims wherein, when the apparatus is in use, the passages extend substantially vertically.

11. Apparatus according to claim 10 including partitions inside the outer cabinet between the cabinet and the inner container or containers and wherein the passages are formed between the partitions.

12. Apparatus according to claim 11 wherein the outer cabinet and the inner container or containers are box shaped and the partitions extend between inner corners of the cabinet and outer corners of the inner container or containers.

13. Apparatus according to any one of the preceding claims including four passages, wherein the outer cabinet includes a first cabinet vent adapted to allow air to enter a first one of the passages and a second cabinet vent adapted to allow air to leave the first one of the passages and the outer cabinet includes a third cabinet vent adapted to allow air to enter a second one of the passages and a fourth cabinet vent adapted to allow air to leave the second one of the passages.

14. Apparatus according to claim 13, wherein the outer cabinet further includes a fifth cabinet vent adapted to allow air to enter a third one of the passages and a sixth cabinet vent adapted to allow air to leave the third one of the passages and the outer cabinet includes a seventh cabinet vent adapted to allow air to enter a fourth one of the passages and an eighth cabinet vent adapted to allow air to leave the fourth one of the passages.

22 CMO8532JGBIDJM 15. Apparatus according to claim 13 wherein the outer cabinet includes at least one baffle plate or panel which seals one of the passages.

16. Apparatus according to any one of the preceding claims wherein the outer cabinet has at least four side faces and is adapted to receive in each of its side faces a removable plate or panel either of a first kind which has at least one of the cabinet vents or of a second kind which is without vents to seal one of the passages, at least two of the plates being of the first kind.

17. Apparatus according to claim 16 wherein each of the plates of the first kind when fitted in a side face of the outer cabinet provides a cabinet vent which faces a container vent of an inner container.

18. Apparatus according to any one of the preceding claim 1 and substantially as described herein with reference to the accompanying drawings.

19. A closed container for use as an inner container in the apparatus according to any of the preceding claims, the container having a plurality of vents including a first inlet vent in a first side face of the container, a second inlet vent in a second side face of the container, a first outlet vent in a third side face of the container and a second outlet vent in a fourth side face of the container, wherein the first and second side faces are adjacent to one another and have a common corner and the third and fourth side faces are adjacent to one another and have a common corner.

20. A container according to claim 19 which includes electronic equipment modules therein which are stacked 23 CM08532/GB/DJM with vertically extending gaps between them to allow air to flow upwardly between the modules to withdraw heat from the modules, wherein the inlet vents of the container are formed in the first and second side faces at a height not above the bottom of the modules and the outlet vents are formed in the third and fourth side faces at a height not below the top of the modules.