REFRIGERATION AND FREEZING CONTAINERS

The invention relates to a stackable service unit for operating and maintaining the re- frigeration machinery and the freezing machinery of, respectively, refrigeration and freezing containers, the service unit being arranged to be placed in a storage area, the service unit comprising a frame enclosing a service room and being provided with a bottom portion forming a floor and being provided with a first opening, and side por- tions and end portions surrounding and extending up from the bottom portion and supporting a top portion, an access way extending up from the bottom portion to- wards the top portion, the top portion including a second opening forming a passage between the access way and the service room of an overlying service unit.

When being stored temporarily in harbour areas and the like, standard shipping con- tainers with refrigeration or freezing machinery have a need for energy supply for the operation of the built-in machinery in containers containing refrigerated or frozen car- go, and there is a need to inspect and maintain the machinery. Machinery of this kind generates noise, and there may also be a need to shield the machinery to reduce the noise level towards the surroundings.

Today, inspection and maintenance are, to a great degree, carried out by way of mo- bile access systems that are brought to the container where it is stored alone or in larger or smaller rows and stacks of containers. In its simplest form, an access system may be a ladder that is put up against an end portion of the container where the ma- chinery is located, or mobile lift platforms of a suitable kind are used.

It is laborious and, in part, connected with danger to establish access to the machin- ery in high stacks of refrigeration or freezing containers. The building height of a standard shipping container is between 2.4 and 2.6 metres, and it is not unusual to stack four containers in height. The top of the fourth and uppermost container will thereby be about 10 metres above the ground. The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art or at least provide a useful alternative to the prior art.

The object is achieved through the features that are specified in the description below and in the claims that follow. The invention provides a stackable service unit for use in the operation and mainte- nance of refrigeration and freezing containers. The service unit has a building height corresponding to that of the container and a building length corresponding to a multi- pie of the building width of the container. In a preferred embodiment, the service unit has external measurements corresponding to those of a standard 40-foot shipping container, that is to say with a length corresponding to the width of five standard shipping containers.

The service unit is adapted for several to be stacked in height and several in a row for the establishment of a service rig in a container storage area. The service rig may be established permanently or temporarily, and it may easily be expanded or reduced in size by varying use of the area in which the containers are stored.

The service rig comprises a varying number of service units grouped together for use at the operation and maintenance of a varying number of refrigeration and/or freezing containers that are being placed at the grouped service units with end portions includ- ing, respectively, refrigeration and freezing machinery facing the long side of a corre- sponding service unit and being adjacent thereto. Containers may be stacked at both of the long sides of the service units in a service rig. The service rig may comprise several service units stacked in height and several service units standing in a row.

The service unit includes a frame defining a service room provided with a bottom por- tion which forms a floor, a top portion arranged at a distance above the bottom por- tion and side portions and end portions extending up from the bottom portion and supporting the top portion. The bottom portion is penetrated by an opening.

In an alternative embodiment, the service unit is provided with end sections which, when the service unit is in an operative position, extend the floor of the service unit, for example by a service unit with a transport length corresponding to that of a stand- ard 20-foot shipping container being extended to a length corresponding to that of a 32-foot shipping container, that is to say with an operative length corresponding to the width of four standard shipping containers, by the bottom portion of the service unit being extended by the end sections, possibly being pivotably supported in or at the bottom portion, being pivoted outwards into a horizontal position, or by the end sections being attached to the end portions of the service unit.

An access way, typically in the form of a stairway, extends up from the bottom portion towards the top portion from an opening in the bottom portion. Appropriately, a verti- cal projection of an upper end of the access way substantially coincides with a first side edge of said opening in the bottom portion. For a straight access way, the open- ing is preferably rectangular and extends from said first side edge towards an oppo- site, second side edge, the opening forming a passage between the access way of an underlying service unit and the service unit of said opening, so that, via the access way, personnel and equipment can be moved between the service room in a service unit and the service room in an underlying service unit. A straight access way prefera- bly extends in the longitudinal direction of the service unit. The access way is not re- stricted to being straight but may appropriately be formed with one or more direction- al changes.

The top portion may be open or be formed with braces that provide improved lateral stability in the service unit and can support the bottom portion of an overlying service unit, for example in the form of a horizontal latticework structure.

The access way extends up from the bottom portion and is supported in the bottom portion and possibly in the top portion. The opening forms further side edges which are bounded by guard rails or equivalent means extending up from the bottom portion and preventing access through the opening beyond the ordinary access to the access way via the first side edge, which may appropriately be closable with a gate or some other suitable barrier.

The bottom portion of each service unit, possibly together with the latticework struc- ture of the top portion, forms a floor in a stack of service units. The side portions and end portions of the service unit may be open or closed and may be provided with shielding means preventing personnel and objects that are stored in the service unit from falling out. The shielding means may be guard rails, gates, fenc- es, half walls and fully covering walls or a combination of two or more of these. To facilitate access to the machinery in an adjacent container, it is an advantage if at least parts of the shielding means at one or both side portions can be removed or have suitable openings that can facilitate the access to the machinery of adjacent con- tainers.

The service unit may be provided with a power-distribution system with a first connec- tion point for the supply of electrical energy from an external power-supply installa- tion. The power-distribution system is typically arranged to deliver electrical energy to the machinery of all the containers adjacent to the service unit. It is also an ad- vantage if the service unit is provided with a second connection point for electrical energy to be transmitted to the power-distribution system of an adjacent service unit. The supply of electrical energy to an entire service rig may thereby go through one connection point connected to the external power-supply installation.

The service unit is arranged to provide air exchange for the machinery of all the con- tainers connected. This may take place through flow paths ending in openings in the free sides of the service unit, typically at the ends of the service unit, possibly via ver- tical flow paths ending in or above the top portion of the uppermost service unit. Per- forated floors in each of the service units may constitute parts of the vertical flow paths.

The internal volume of the service unit and especially the flow paths for air exchange may include sound-absorbent means to provide noise reduction of the machinery of the containers.

The top portion of the uppermost service unit in a stack of service units may practical- ly be provided with a removable, sealing roof which may also include sound-absorbent means and openings for air exchange with the interior of the service rig.

Preferably, each service unit is designed for locking connection to an overlying service unit. It is also an advantage if at least the surface on which the service rig is standing is designed for locking attachment of the lowermost service unit to the surface. It is an advantage if the locking means comprise locks of the "Twistlock" type, which is a standardized, rotatable container connector, arranged in the upper corner portions of the service unit, possibly also integrated in the surface on which the service units of the service rig are standing, and corresponding engagement portions in the lower cor- ner portions of the service unit. The optional removable roof may also be provided with engagement portions for locking engagement with the locks of the adjacent ser- vice unit.

The service unit is preferably formed with a frame formed as a latticework structure, preferably made of aluminium to reduce the need for maintenance and also to reduce the weight of the service unit and thereby the carrying capacity of the frame, by the very fact of it being an advantage if all the service units are of the same design and can be randomly placed in the group of service units of the service rig. A service unit with measurements corresponding to those of a standard 40' container may typically weigh a little less than 2500 kg.

The invention is defined by the independent claims. The dependent claims define ad- vantageous embodiments of the invention.

In a first aspect, the invention relates more specifically to a stackable service unit for the operation and maintenance of the refrigeration machinery and the freezing ma- chinery of, respectively, refrigeration and freezing containers, the service unit being arranged to be placed in a storage area for refrigeration and freezing containers, wherein the service unit comprises:

a frame enclosing a service room and being provided with a bottom portion forming a floor and being provided with a first opening, and side portions and end por- tions surrounding and extending up from the bottom portion and supporting a top por- tion,

an access way extending up from the bottom portion towards the top portion, the top portion comprising a second opening forming a passage between the access way and the service room of an overlying service unit, characterized by

the floor forming a working platform surrounding the entire first opening and providing a personnel access way to all the side portions and end portions of the frame,

the side portions and end portions being provided with shielding means defining the floor and forming closable side openings between the service room and the sur- roundings of the service unit.

The top portion may be formed as a horizontal latticework structure.

A vertical projection of an upper end of the access way may substantially coincide with a side edge of the first opening, the first opening extending towards a lower end of the access way.

The side portions may be provided with shielding means forming side openings.

The service unit may be provided with a power-distribution system comprising :

a first connection point adapted for the supply of electrical energy to the pow- er-distribution system,

a distributor adapted for the outlet of electrical energy to the refrigera- tion/freezing machinery of several containers,

a second connection point adapted for the transmission of electrical energy to the power-distribution system of an adjacent service unit. The frame may have external measurements corresponding to those of a standardized 40-foot ISO container.

An end section may be pivotably attached at each end portion and is arranged to form an extension of the floor out from the end portion by being pivoted from a vertical transport position into a horizontal operative position.

An end section may be pivotably attached at each end portion and is arranged to form an extension of the floor out from the end portion by being pivoted from a vertical transport position into a horizontal, operative position, and, in a transport position, the service unit may have external measurements corresponding to those of a standard- ized 20-foot ISO container, and, in an operative position, has external measurements corresponding to those of a standardized 32-foot ISO container.

In lower corner portions of the frame, engagement portions may be arranged for re- leasable connection to lock attachments arranged in the storage area or to upper cor- ner portions of the frame of an underlying service unit. In the lower and upper corner portions, engagement portions may be integrated, adapted for engagement with locks of the Twistlock type or the like.

The service unit may be provided with a detachable, sealing roof attached with locks to the frame.

The service unit may be provided with sound-absorbent means formed as absorption elements completely or partially covering one or more of the side portions, end por- tions and top portion.

The access way may be a stairway.

In a second aspect, the invention relates more specifically to a service rig for operat- ing and maintaining the refrigeration machinery and the freezing machinery of, re- spectively, refrigeration and freezing containers, the service rig comprising one or more stacks of service units as described above, and one or more refrigeration and freezing containers arranged in a storage area with, respectively, the refrigeration machinery and freezing machinery facing the side portion of a service unit, and at least the service units of the service rig being releasably secured to the storage area, and the service units being connected to a power-supply installation.

In what follows, examples of preferred embodiments are described, which are visual- ized in the accompanying drawings, in which: Figure 1 shows a perspective drawing of a first exemplary embodiment of a ser- vice unit according to the invention;

Figure 2 shows a perspective drawing, on a smaller scale, of a group of service units in a service rig comprising a stack of four service units; Figure 2a shows a section, on a larger scale, of a connection between two service units in a service rig;

Figure 2b shows a perspective view of a lock for connecting a service unit to a supporting surface;

Figure 3 shows a side view, on a larger scale, of the group of service units in the service rig according to figure 2;

Figure 4 shows an end view of the service rig according to figure 2 with stacks of refrigeration or freezing containers arranged at the group of service units;

Figure 5 shows a perspective drawing of a service unit provided with a roof and noise-reducing means;

Figure 6 shows a section, on a larger scale and in perspective, of a service unit with a detachable end section; and

Figure 7 shows, on a smaller scale, the stack of a service rig of four service units according to figure 6. Reference is first made to figure 1, in which a first exemplary embodiment of a service unit 1 according to the invention is shown. A frame 11 comprises a bottom portion 111 which forms a floor 1111. The bottom portion 111 is surrounded by opposite side por- tions 113 and intermediate end portions 114 defining the floor 1111 and extending up from the bottom portion 111 and supporting a top portion 112. The frame 11 defines a volume which forms a service room 115. At least the side portions 113 and the end portions 114 are formed as latticework structures to provide rigidity and carrying ca- pacity in the frame 11. The external measurements of the frame 11 correspond to those of a standard ISO shipping container, shown in figures 1-5 with dimensions cor- responding to those of a 40-foot container. Reference is now made especially to figures 2, 2a and 2b. The service unit 1 is stacka- ble, and in lower corner portions 1113 and upper corner portions 1123 of the frame 11, standardized engagement portions 1171 and 1172, respectively, have appropriate- ly been arranged for rotatable locks 1173 of the Twistlock type or an equivalent, uni- versally known for the securing of ISO-standardized shipping containers. A first ser- vice unit 1 may be secured in lock attachments 21 integrated in a storage area 2 by means of a set of locks 1173 that engage with the lock attachments 21 and the lower corner portions 1171 of the first service unit, and further locks 1173 form releasable connections between the upper corner portions 1123 of the first service unit 1 and the lower corner portions 1113 of the adjacent overlying service unit 1.

Reference is made to figure 1 again. The floor 1111 is provided with a rectangular first opening 1112 defined by a first side edge 1112a, an opposite second side edge 1112b and intermediate third and fourth side edges 1112c. The floor 1111 surrounds the en- tire said first opening 1112 and forms a spacious working platform which constitutes an access way for personnel who are to have access to adjacent elements from all side and end portions 113, 114 of the frame 11, for example to refrigeration or freezing containers 4 as is shown in figure 4. It is an advantage if the access way is continu- ous, so that personnel can move freely along the side and end portions 113, 114.

An access way, shown in the figures as a stairway 118, extends up from the bottom portion 111 towards the top portion 112 at a distance from the side portions 113 and end portions 114 of the frame extending upwards, and a vertical projection of an up- per end 1182 of the stairway 118 substantially coincides with the first side edge 1112a of the opening 1112 in the floor 1111, and a lower end portion 1181 of the stairway 118 rests on the bottom portion 111 near the second side edge 1112b. Stairway rail- ings 1183 define the sides of the stairway 118.

In the embodiment shown, the upper end 1182 of the stairway 118 rests on a beam in a horizontal latticework structure 1121 in the top portion 112, where a second opening 1122 is formed, which, in a vertical projection, at least coincides with the first opening 1112 in the floor 1111.

Alternatively, the top portion 112 may form an open top without transverse beams and diagonal braces. With such an embodiment of the top portion 112, the stairway 118 may be supported in the bottom portion 111, for example with posts (not shown) extending between the floor 1111 and the upper end 1182 of the stairway 118.

The stairway 118 and the opening 1122 in the top portion and also the opening in the floor 1111 of the overlying service unit 1 thereby form an access way between the service rooms 115 of vertically adjacent service units 1. See in particular figures 3 and 4.

In a service rig 5 comprising a stack of service units 1, several refrigeration or freez- ing containers 4 may be included, see figure 4, wherein container end portions 41 ac- commodating refrigeration machinery and freezing 42 machinery, respectively, (also called "machinery" in what follows) are facing the side portions 113 of the service units 1. From the respective service rooms 115, personnel may gain access to said machinery 42 to perform necessary maintenance and operations.

Reference is made to figure 1 again. The machinery 42 may have energy supplied to it through a distribution system 12 arranged in each service unit 1, typically in the form of electrical power which is supplied from a power-supply installation 3 (see figure 2) connected to the storage area 2. The distribution system 12 is typically provided with a first connection point 121 for the inlet of electrical power, and a second connection point 122 for the outlet of electrical power to an adjacent service unit 1, and also sev- eral outlets 123 for connection to the machinery 42 of adjacent refrigeration/ freezing containers 4.

The side portions 113 and the end portions 114 are preferably provided with shielding means 116, at least in the form of guard rails, possibly as full or half walls with gates that can be opened and possibly removed for access to the machinery 42 and for air exchange. With advantage, the shielding means 116 may be noise-reducing towards the surroundings. It is an advantage if the shielding means 116 can be removed sec- tionally, so that unobstructed access to the machinery 42 of a refrigeration/freezing container 4 may be provided. With advantage, the shielding means 116 have a sec- tioning corresponding to the width of the refrigeration/freezing container 4.

Reference is now made to figure 5, in which the service unit 1 is shown with a detach- able roof 13 which both shields the service unit 1 against precipitation and is noise- reducing towards the surroundings or carries noise-deadening means in the form of absorption elements 1191 that are attached to the roof 13, and airflow channels 1192 that guide the air exchange between the machinery 42 and the surroundings in a par- ticular direction. The roof 13 is typically attached to the service unit 1 with suitable locking means, preferably with locks (not shown) that engage with the engagement portions 1172 in the top portion 112 of the frame 11.

A service unit 1 according to the first embodiment typically has external measure- ments corresponding to those of a 40-foot ISO-standardized shipping container, and it may then form a service access for five refrigeration/freezing containers 4 on each long side (along each side portion 113).

Reference is now made to figures 6 and 7. I a second exemplary embodiment, the service unit 1 is formed with detachable end sections 1141 which are connected to the end portions 114 of the frame 11. The end sections 1141 form extensions of the floor 1111 out from the end portions 114. In this embodiment, a service unit 1 typically has a transport length, that is to say with end sections 1141 detached, corresponding to that of a 20-foot ISO-standardized shipping container, but the length in an operative position, that is to say with end sections 1141 attached, corresponding to that of a 32- foot ISO-standardized shipping container and may thereby form a service access for four refrigeration/freezing containers 4 on each long side (along each side portion 113 and the end sections 1141). In this embodiment, the lowermost service unit 1 in a service rig 5 may be simplified, as the end sections 1141 may be omitted, as is shown in figure 7.

In an embodiment not shown, the end sections 1141 are pivotably attached to the frame 11, as, for transport purposes, they may be raised into a vertical position.

It should be noted that all the above-mentioned embodiments illustrate the invention, but do not limit it, and persons skilled in the art may construct many alternative em- bodiments without departing from the scope of the attached claims. In the claims, reference numbers in brackets are not to be regarded as restrictive. The use of the verb "to comprise" and its different forms does not exclude the pres- ence of elements or steps that are not mentioned in the claims. The indefinite article "a" or "an" before an element does not exclude the presence of several such elements.

The fact that some features are indicated in mutually different dependent claims does not indicate that a combination of these features cannot be used with advantage.