FIELD OF THE INVENTION

The present invention relates to a drying apparatus, in particular for use in a freight container. The present invention relates also to a dehumidifier for use in the apparatus of the invention and to a device for mounting the dehumidifier in the container.

BACKGROUND OF THE INVENTION

Cargo of various kind is shipped in aluminium or steel freight or transport containers usually being approximately 8x8x20 or 8x8x40 feet in size. Recently a freight container approximately 8x8x13 feet in size has been proposed as a new standard (WO 01/62631) . A modular freight container of this sort is of generally rectangular parallelepipedal form and comprises a base, a pair of opposed side walls, at least one of which comprises a door, usually a double wing door, for loading and unloading freight, and a roof. The walls are usually made of corrugated plate. While freight containers are made to withstand severe weather conditions they are generally not airtight. To seal them completely is costly.

Due to changes in temperature of the air inside of the freight container or in the atmosphere surrounding it, changes in atmospheric pressure, wind pressure, and the like, a difference in pressure between the air in the container and that surrounding it may be created, causing humid air to leak into the container from outside and to affect cargo sensitive to humidity. Dehumidifying devices suitable for or specifically designed for use in freight containers, such as

those disclosed in U.S. patents nos . 5,676,739, 6,273,942, 6,344,072, and 6,423,122, are known in the art.

Known devices, which are generally of an oblong shape, are mounted in the container pending from steel lashing eyes welded to the inside of the container side walls. The eyes are designed for attaching belts, straps, etc. fastened at the freight to prevent it from moving during transport. Eyes or hooks are however not normally provided at the ceiling of freight containers . A problem with known devices is that they often become disposed at the level of freight. To avoid damage attention to their presence has to be given when the container is loaded or emptied, and also when the freight is secured against displacement in the container.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a drying apparatus for use in a freight container, which is easy to mount and to demount, and the risk of which to interfere with the freight or with loading and unloading is substantially reduced.

Other objects of the invention will be evident to a person skilled in the art by studying the following summary of the invention, a description of preferred embodiments thereof illustrated in a number of figures, and the appended claims.

SUMMARY OF THE INVENTION

The present invention is based on the insight that a lashing eye of the aforementioned kind or other fixture disposed at an inner side wall of the container or even at a venting bore in such wall can be used for mounting a known or

novel dehumidifier in a novel manner, that is, in clamped abutment with the container ceiling.

Accordingly the present invention discloses a drying apparatus for mounting in a freight container, comprising a dehumidifier capable being mounted in abutment with the container ceiling, a support means for supporting the dehumidifier capable of being mounted at a fixture disposed at an inner wall of the container or at a venting bore in said wall, and a clamping means disposed on the support means for clamping the dehumidifier against the ceiling. A preferred fixture is a lashing eye, extending in a horizontal or skew direction from the inner wall of the freight container.

It is preferred for the support means to comprise a hook portion for mounting at the lashing eye or other fixture extending from an inner side wall face of the container or in a venting bore in the side wall, and an oblong slide portion extending, in a mounted position, to a substantial degree beneath the hook portion. The hook and slide portions are preferably integral and of polymer material. It is preferred for the slide portion to extend generally vertically and parallel with the container wall in a mounted (clamped) state; it is however also within the scope of the invention that its extension may deviate somewhat from that direction so as to form an acute angle (towards the ceiling) with the container wall at which it is mounted. In a mounted state a lower end section of the slide portion or a spacer portion extending from that section in the direction of the container side wall abuts the container wall carrying the fixture or venting bore. According to a preferred aspect of the invention the dehumidifier is slidingly mounted on the clamping device so as to be slidingly displaceable along the slide portion thereof, the displacement preferably being in a substantially vertical direction.

In a mounted (clamped) state it is preferred for the slide portion to be disposed substantially between the dehumidifier and the lashing eye or other fixture.

According to a preferred aspect of the invention the dehumidifier comprises a rigid or semi-rigid casing and a guide shoe fixed at or integral with the casing. The guide shoe is slidingly mounted on the slide portion, for instance on a sliding rail. It is however also possible for the slide portion to comprise a guide shoe extending along it, which guide shoe encloses, in a mounted state, a sliding rail fixed at or integral with the dehumidifier casing.

According to another preferred aspect of the invention, the dehumidifier can be secured at a selected position, preferably at any position, over a distance along the slide portion. In particular, it can be secured at a position at which the top of the dehumidifier abuts the container ceiling, which position is the mounting (clamping) position of the dehumidifier in the container. To allow the dehumidifier of the invention to be correctly mounted, the longitudinal extension of the slide portion including that of its sliding rail portion has to be chosen in consideration of the distance between the eye or other point of fixation, while additionally taking into account the vertical extension of the dehumidifier and the disposition of the hook element; this selection and consideration is within the easy reach of a person skilled in the art.

In a mounted state the dehumidifier of the invention comprises a desiccant, preferably a deliquescent desiccant, housed in the casing. The casing is preferably made of polymer material. It can be made in one piece, such as by form blowing, or be assembled from several parts produced by, for instance, injection moulding. The casing may comprise a generally horizontally extending partition by which it is divided into two compartments . The upper compartment houses

the desiccant; it communicates with the lower compartment by channels or other kind of through openings in a manner so as to retain the deliquescent desiccant in the upper compartment while allowing liquid formed from it by contact with humidity to drain into the lower compartment. Access of humid ambient air to the desiccant is by through openings in the wall(s) of the upper compartment. It is however also possible to use a desiccant that is not deliquescent, in particular a desiccant that can be regenerated. In such case there is no reason for dividing the casing into two compartments.

In this application the terms "front", "rear", and "side" are defined by the perspective of an observer looking at the apparatus of the invention in the direction of the container wall at which it its clamping device is fixed. "Horizontal", "vertical", "upper", "lower", "top", and "bottom" in respect of the dehumidifier and the clamping device relate to their disposition mounted in a container. The term container "side wall" includes the end wall opposite to the container door. While the dehumidifier, the support means, and the clamping means are described herein as a combination of separate, demountable entities, they or some of them may also be combined in a manner making disassembly difficult or only possible at risk of damage. Combinations of this kind are within the easy reach of a person skilled in the art and thus comprised by the present invention.

The dehumidifier of the invention may be provided charged with drying agent or empty, in which case the drying agent will have to be provided separately for charging prior to use. Anhydrous calcium chloride is a preferred deliquescent drying agent. Silica gel is a preferred non-deliquescent regenerable drying agent.

According to the present invention is furthermore disclosed a device for mounting the dehumidifier in the

container, the mounting device comprising a support means and a clamping means that is slidingly displaceable on the support means, the support means comprising a hook portion and an oblong slide portion, the clamping means comprising a slide shoe portion and a means for arresting it in a desired position.

Further advantageous aspects of the invention are disclosed in the appended claims.

The invention will now be explained in more detail by reference to a number of preferred but not limiting embodiments shown in a drawing.

SHORT DESCRIPTION OF THE FIGURES

Fig. 1 is a first embodiment of a dehumidifier of the invention comprising a housing consisting of a cover, a receptacle, and a partition element, in an assembled state, in a vertical longitudinal section D-D (Fig. 5); Fig. 2 is a horizontal section A-A (Fig. 1) of the embodiment of Fig. 1; Fig. 3 is the same section as in Fig. 2, with the receptacle and the partition element omitted;

Fig. 4 is a horizontal section B-B (Fig. 1) of the embodiment of Fig. 1;

Fig. 5 is a vertical transverse section C-C (Fig. 1) of the embodiment of Fig. 1; Fig. 6 is the embodiment of Fig. 1, in a storage and transport state, in a section corresponding to that of Fig. 1;

Fig. 6a is an enlarged detail of Fig. 6, in the same section; Fig. 7 is an enlarged detail of the combination of the dehumidifier of Fig. 1 and the clamping device of the invention illustrated in Fig. 8, in a state mounted

at a lashing eye, in horizontal section E-E (Fig.

8a); Fig. 8 is the combination of the dehumidifier of Fig. 1 and a first clamping device of the invention, in a loosely mounted state, and in a vertical transverse section corresponding to that of Fig. 5; Fig. 8a is the combination of Fig. 8 in a final mounted

(clamped) state, in the same view; Fig. 8b is a partial view of Fig. 8, enlarged; Fig. 8c is another partial view of Fig. 8, in horizontal section F-F (Fig. 8a), enlarged; Fig. 9 is a partial side view of the combination of Fig. 8, with an damping patch added;

Fig. 10 is the combination of a variant of the dehumidifier of Fig. 1, and a second clamping device of the invention, in a final mounted (clamped) state and in the same view as the combination of Fig. 8; Fig. 10a is a partial view of the combination of Fig. 10, enlarged; Fig. 11 is the combination of the dehumidifier of Figs.

1-6 and a third clamping device of the invention, in a final mounted state and in the same view as the combination of Fig. 8;

Fig. 12 is a second embodiment of the dehumidifier of the invention, in a front view;

Fig. 13 is a top view of the dehumidifer of Fig. 12;

Fig. 14 is a horizontal sectional view K-K (Fig. 12) of the dehumidifier of Fig. 12;

Fig. 15 is a side view of the dehumidifier of Fig. 12; Fig. 16 is the combination of the dehumidifier of Fig. 12 and a fourth clamping device of the invention, loaded with a bag of desiccant, assembled but not mounted, in a vertical transverse section H-H (Fig. 12); Fig. 17 is a rear view of the combination of Fig. 16.

The dehumidifier of Figs. 1-6 comprises of an oblong housing formed by two trough-shaped halves termed cover 10 and receptacle 20 (Figs. 3 and 4). The inner space of the housing 10, 20 is divided by a horizontally disposed partition element 30 into an upper compartment U and a lower compartment L. The housing 10, 20 and the partition element 30 are of a stiff polymer material such as injection-moulded polystyrene. The receptacle 20 has a flat bottom 21, short side walls 22, 22' and long side walls 23, 23' . At a short distance from the rectangular rim of the receptacle 20 shoulders 24, 24', 24'', and 24''' extend inwardly from the centre of the respective wall 22, 22', 23, 23'. From the outer face of rear long side 23' extend two vertically disposed mirroring L-shaped flanges 25, 26 forming a T-shaped vertically extending channel between them centred in respect of the rear wall 23' .

From the rim to the level of the support faces of the shoulders 24, 24', 24", 24'" the receptacle wall short and long side walls 22, 22' and 23, 23', respectively extend vertically to form vertical wall sections 27, 27', 28, 28'; from there onwards they converge in direction of the bottom 21. The cover 10 comprises a corresponding vertically extending circumferential short wall section 17, 17' and long wall section 18, 18' of equal height bordering to the main section of the cover in which the short 12, 12' and long 13, 13' side walls converge in direction of the top wall 11. The vertically extending wall sections 17, 17', 18, 18' of the cover 10 fit snugly inside of the vertically extending wall sections 27, 27', 28, 28' of the receptacle 20 but are hindered from further insertion by the converging receptacle walls 22, 22', 23, 23'; they would not be hindered by the shoulders 24, 24', 24", 24"' since the vertical wall sections 17, 17', 18, 18' carry vertically extending centred slits 14, 14', 14", 14'", which extend a short distance into the corresponding converging wall portions 12, 12', 13, 13'.

The shoulders 24, 24', 24'', 24''' are designed to support the partition element 30, which is of a rectangular shape and has vertically extending short 31, 31' and long 31'', 31''' side wall sections that fit snugly into the vertically extending portions 17, 17', 18, 18' of the cover's 10 side walls 12, 12', 13, 13' .

The partition element 30 has a bottom comprising two oblong sections 35 and 36 inclined towards each other. They are joined to opposite short sides of a horizontal central bottom section 33. Slits 34 in the horizontal bottom section 33 provide for communication between the upper compartment ϋ_ and the lower compartment L of the housing.

The partition element 30 is designed for holding deliquescent granular CaCl ₂ 41 or another appropriate deliquescent drying agent such as sodium hydroxide. The long side walls 13, 13' of the cover 10 are provided with an array of circumferentially extending through openings 15, 15' to allow humid ambient air to contact the drying agent 41. Aqueous calcium chloride solution 42 thereby formed leaves the upper compartment U via the slits 34 and accumulates at the bottom 21 of the lower compartment IJ.

The dehumidifier of Figs. 1-6 has the additional advantage of a storage and transport volume that is only about half its assembled volume (Fig. 6) . For storage and transport the parts of the dehumidifier can be packed in the following manner: The receptacle 20 is put on a flat surface. Then the cover 10 is inserted upside down into the receptacle 20. Next the partition element 30 filled with drying agent 41 is inserted into the cover 10 in its normal (assembled) position. Finally a seal of polyethylene foil 50 comprising a lip 52 for easy removal is attached to the circumferential end face of the receptacle wall sections 27, 27', 28, 28'. In addition the upper circumferential end face of the partition element 30 may

receive a seal 51 to prevent drying agent 41 from being accidentally dispersed.

Figs. 7-8c illustrate the combination of the dehumidifier of Figs. 1-6 with a first embodiment of the clamping device of the invention. The oblong clamping device 60 comprises a rod element 64 with an upper end and a lower end so defined by its vertically mounted disposition. Near its upper end the clamping device 60 carries an integral hook 61. Near its lower end the clamping 60 device has an integral spacer 63 extending from its rear side and which abuts the container wall 71 in a mounted position. The purpose with the spacer 63 is to keep the rod element 64 vertically disposed. As shown in Fig. 7 the rod element 64 has a T-profile 62 in a horizontal section. The T-profile fits snugly into the aforementioned T-shaped vertically extending channel formed by the mirroring L-shaped flanges 25, 26 that extend from the rear wall 23', 28' portions of the receptacle 20. This allows the dehumidifier to be slidingly displaced along the clamping element 60 without coming off. Fig. 8 illustrates the first step of mounting the combination in a freight container. The hook 61 hung up in a lashing eye 70 mounted at a side wall 71 of the container; in this figure the top of the dehumidifier is at a distance from the ceiling 72 of the container. Also shown is a lock 80 comprised by the clamping device 60. The lock 80 runs freely on the T-profile 62 of the rod 64 to which it is kept attached by L-shaped flanges 87, 88. It comprises a housing 89 in which a locking arm 81 is rotatably mounted on a shaft 83 disposed horizontally and parallel with the front face 62' of the T- profile 62. The locking arm 81 extends through an opening 84 in the housing 89. Except for a sector 82' of slightly larger diameter comprising a flat outwardly facing circumferential face the journalled end of the locking arm 81 has a circular profile 82 that barely abuts said front face 62' of the

T-profile 62 so as not to bar displacement of the lock 80 along the rod element 64. The sector 82' is separated from the remainder of the circular profile 82 by slits 85, 86, which render the sector 82' somewhat flexible in a circumferential direction. When the circumferential face of the sector 82' is brought into abutment with the front face of the T-profile 62 by turning the free end of the arm 81 the lock 80 becomes arrested against displacement along the rod element 64. By its own weight the dehumidifier rests on the top face of the housing 89 (Figs. 8a, 8b). Fig. 8a illustrates the dehumidifier in a mounted (clamped) position. The dehumidifier of the invention reaches this position and becomes locked in it by being manually pushed upwards along the rod element 64 until the top wall 11 of its cover 10 abuts the container ceiling 72, followed by (or simultaneous with) displacing the lock 80 in the same direction until the upper face of its housing 89 abuts the bottom 21 of the recipient 20. Finally the lock 80 is arrested by turning the locking arm 81 in the manner described above. In other words, the humidifier of the invention has now become clamped between the lashing eye 70 and the container ceiling 72. As shown in Fig. 9 a resiliently compressible patch 17 of, for instance, polyurethane foam may be glued on the top 11 of cover 10 to dampen the effect of sudden bumps and vibration that may affect the container during transport.

In the embodiment of Figs. 10 and 10a the dehumidifier of Figs. 1-6 is arrested by a wedge element 180 substituted for the lock 80 of the first embodiment of the clamping device. The wedge element 180 is provided with a saw- tooth profile 181 on one of its wedge faces. The front face of the T-profile of the rod element 164 is provided with a corresponding saw-tooth profile 181' . In all other respects the combination of dehumidifier and the clamping device 160 is identical with that illustrated in Figs. 8a-8c. As explained

earlier for the embodiment of Figs. 8a-8c the combination is loosely mounted at a latching eye 170 fastened at a container side wall 171 by a hook 161 integral with the clamping device 160. By displacing the dehumidifier upwards along the rod element 164 of the clamping device 160 it is brought in a position in which the top wall 111 of its cover 110 abuts the ceiling 172. Then the wedge element 180 is inserted from below in the upwardly narrowing space between the front face 165 of the T-profile and the converging rear wall 123' of the receptacle 120 in a manner that the wedge face provided with the saw-tooth profile 181 faces front face of the T-profile provided with the saw-tooth profile 181' , and forcing it further upwards to make the saw-tooth profiles 181, 181' interlock so as to firmly clamp the dehumidifier against the ceiling 172 of the container. In this embodiment 141 designates the deliquescent drying agent, 142 the aqueous solution formed by contact of the deliquescent agent 141 with humidity in the atmosphere surrounding the dehumidifier. In the embodiment of Fig. 11 the dehumidifier of Figs. 1-6 is again shown in a state locked (clamped) against the container ceiling 272 which the top of its cover 210 abuts. Locking is accomplished by a screw 265 arranged in a threaded through bore of a horizontal end section 262 of the clamping device that extends in a direction away from the container wall 271 at which a lashing eye 270 is fixed. The end section 262 joins the rod section 264 at the level of a spacer 263, the purpose of which is the same as that of spacer 63. The screw 265 has a handle 266 at its lower end and a base 267 at its upper end. In the clamped position of the assembly the upper face of base 267 abuts the bottom 221 of the receptacle 220, which is thereby supported. The receptacle 220 is partially filled with an aqueous solution 242 of a deliquescent drying agent 241.

Figs. 12-17 illustrate a further embodiment of the invention, the dehumidifier of which has been manufactured in one piece by blow moulding and thus has rather thin and somewhat flexible walls. This dehumidifier is about rectangular in a front view and of small depth, i.e., the distance between its front and rear wall. All openings in the dehumidifier wall except for the inblow opening were cut out from the raw blow-moulded device. Sufficient rigidity is imparted to it by a corrugated wall profile, cf . the array of parallel grooves 316, 336. The dehumidifier has an upper desiccant compartment V and a lower desiccant solution compartment W corresponding to compartments O_ and IJ, respectively, in the embodiment of Figs. 1-11. The compartments are separated by a V-shaped partition wall 332 interrupted by channels 334 (channel wall 333) and 334'

(channel wall 333' ) , which provide for communication between the upper and lower compartments V and W. Arrays of through openings 315 are arranged in the front and rear walls 312 of the upper compartment V, which has a large opening 317 (the blow opening) at its one short side. The opening 317 is surrounded by a thickened rim 318, which can be used for mounting a lock of appropriate size (not shown) . Deliquescent desiccant 341 in an air- and water-permeable bag 343 is loaded into the upper compartment V through the inblow opening 317. Desiccant solution 342 accumulates at the bottom of the desiccant solution recipient compartment W, the wall of which is identified by reference no. 322. Near its centre the solution recipient compartment W has a through opening 339 around which the compartment wall 322 forms a double truncated cone section with the small cone bases facing each other and forming an annular wall section 338 with a central through opening 339. A corresponding mirroring conical wall section is disposed at the rear wall making the annular wall section 338 to be disposed about midway between the front and rear walls

of the dehumidifier. The through opening in the annular wall section 338, and the adjacent wall sections 337, 338 are arranged for mounting the clamping device 360.

The clamping device 360 comprises a rod-like clamping element 360' near the one end of which a hook 361 is disposed. With the clamping device 360 mounted at the dehumidifier the hook 361 extends away from the dehumidifier. At its face facing away from the dehumidifier the clamping element 360' carries a saw-toothed profile 362, which cooperates with a corresponding profile arranged at an inner (front) face of a through opening 384 in a rectangular non-slotted screw head 385, through which opening 384 the clamping element 360' extends. In an unlocked state of the screw head 385 the dehumidifier can be displaced along the clamping element 360' . The through opening 384 extends in a direction perpendicular to that of the screw 380, which is provided with right-handed threads 381 only over a portion extending from its free end. The screw head 385 is drawn towards the saw-toothed profile 362 of the clamping element 360' by turning a large threaded nut 382 provided with grips 383 disposed on the threaded 381 portion of the screw 380 in a clockwise direction. Thereby the clamping element 360' becomes locked. For improved function the clamping device 360 is kept at a distance from the rear wall of the dehumidifier by a spacer element comprising a base 350 abutting said rear wall. Spacer flanges 351, 352, 353, 354 extend from the base 350 and support the (front) face of the clamping element 360' opposite to its tooth-shaped profile 362. For passage of the screw 380 a through bore 355 is arranged at the centre of the base 350. Bulges 358, 359 extend from the front face of the base 357 at locations allowing them to become disposed in the V-formed slot defined by container wall section 332, thereby preventing the spacer element to rotate around the screw 380 in a mounted state.