GB2438189A

GB2438189A - Stackable wheeled container

Info

Publication number: GB2438189A
Application number: GB0609816A
Authority: GB
Inventors: Peter Ross
Original assignee: CP Cases Ltd
Current assignee: CP Cases Ltd
Priority date: 2006-05-18
Filing date: 2006-05-18
Publication date: 2007-11-21
Also published as: GB0609816D0

Abstract

A generally rectangular container 1 includes a base (5, Figure 3), a top 7, two opposite sides 11 and two opposite ends 13. The base (5, Figure 3) and the ends 13 define rectangular envelopes (17, Figure 3) at the lower corners 15 of the container; wherein at least one wheel 19 is mounted at one of the lower corners 15, the wheel 15 being positioned entirely within the rectangular envelope (17, Figure 3) of the base (5, Figure 3) and adjacent end of the container 1. Preferably the container 1 is a case. Additionally the container 1 may be provided with stacking formations 23 protruding from the base (5, Figure 3) and top 7.

Description

Container This invention relates to containers. In particular, it

relates to containers for the transportation and storage of scnsitive equipment such as electrical, electronic, military or photographic equipment.

Transportation and storage cases and "racks" for sensitive equipment or material are well known. Commonly, to allow the case or rack to be moved, protruding wheels are provided in a lower corner at one end of the case. Generally the case or rack is lifted at the opposite end to the wheels, to pivot the case or rack on the wheels to an angle at which an adequate clearance between a base of the case and the ground is achieved, so that the case or rack may be pushed or pulled along the ground.

Whilst such an arrangement is generally effective for moving cases along the ground, problems arise when storing or transporting a case, since the wheels protrude from the stacking envelope of the case. That is, the external envelope of the case excluding any feet or stacking elements which intermesh with corresponding stacking elements on similar cases. The problem is increased with a plurality of cases.

Prior art attempts have been made to address this problem. In one example, indents in the lid of a case are provided that conform to the wheels protruding from the base of the case so that identical cases may be stacked on top of each other. This arrangement results in deep lids that take up unnecessary space and is useless if a number of cases from different manufacturers are being stored or transported together, since the protruding wheels prevent effective stacking of the cases. The protruding wheels are generally inconvenient and vulnerable to damage..

An object of the present invention is therefore to provide a container that has one or more wheels which do not protrude from the stacking envelope of the container, or interfere with stacking with simiJar or different containers.

According to the present invention in a first aspect, there is provided a generally rectangular container having a base, a top, two opposite sides and two opposite ends, the base and the ends defining rectangular envelopes at the lower corners of the container; wherein at least one wheel is mounted at one of the lower corners, the wheel being positioned entirely within the rectangular envelope of the base and adjacent end of the container.

According to a further aspect of the present invention there is provided a generally rectangular container having a base, a top, two opposite sides, two opposite ends and stacking formations protruding from the base and the top; wherein the base and the ends define rectangular envelopes at the lower corners of the container; the stacking formations are positioned entirely outside the rectangular envelope; and at least one wheel is mounted at one of the lower corners, positioned entirely within the rectangular envelope of the base and adjacent end of the container, such that when the container is placed directly on top of an identical container, the base of the container contacts stacking formations provided on a lid of the identical container, and the stacking formations provided on the base of the container contact the lid of the identical container.

These arrangements provide a container without any protrusion from the rectangular envelope and therefore enable effective stacking and storage.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a container according to a first embodiment.

Figure 2 shows a side view of the container; Figure 3 shows an enlarged partial side view of the container, showing the lower corner of the container; Figure 4 shows an enlarged partial side view of the container, showing the lower corner of the container, with the wheel removed; a 3 Figure 5 shows a perspective view of a wheel cup in isolation; Figure 6 shows a side view of the wheel cup; Figure 7 shows a side view of the container pivoted on its wheels; Figure 8 shows a perspective view of a container according to a second embodiment.

Figures 1 and 2 show a container in the form of a case. The container comprises a body 2 with an open top that is closed by a lid 4 that may be hinged to the body or connected by catches (not shown). The body 2 and lid 4 of the container I are provided with complimentary stacking formations 23. The container 1 is preferably formed from plastic material by a rotational moulding process.

The container I comprises a base 5, a top 7, two opposite sides 11 and two opposite ends 13. A pair of wheels 19 are mounted in cups 21 on a common axis in a lower corner 15 of the container 1. The wheels preferably compnse "rollerblade" style wheels and have relatively large diameters (about 5 to 8cm). The wheel axis runs parallel to a lower corner of the container 1.

Referring now to Figure 3, an enlarged partial side view of the container 1, showing the lower corner 15 is shown. The profile of the container I is cut away at the lower corner with the base 5 and the end 13 defining a rectangular envelope 17. This envelope is part of the stacking envelope of the container which is defined as the external envelope of the container excluding any feet or stacking elements which are designed to intermesh with corresponding stacking elements on similar cases. The axis of the wheel 19 lies within the profile of the container I and runs parallel to the corner 15. The wheel 19 extends outwardly of the profile of the container 1 but lies entirely within the rectangular envelope 17. The stacking formations 23 are positioned entirely outside the rectangular envelope 17.

There may be provided protrusions, such as ribs, on the ends 13, in such a case these would also be positioned entirely outside the rectangular envelope 17.

Since the wheel does not protrude from the rectangular envelope 17 the container may be placed flat on its base 5 or its end 3 without the wheel 19 contacting the ground or just touching it. Furthermore, since the wheel 19 does not project outside the rectangular envelope 17, the base 5 of the container 1 can contact stacking formations 23 provided on the lid 7 of an identical container and the stacking formations 23 provided on the base 5 of the container I can contact the lid 7 of the identical container without any interference from the wheel 18. There is therefore, no special provision for acconimodation of the wheel required in the lid 4 of the containers.

Referring now to Figure 4, an enlarged partial side view of container 1, showing the lower corner 15 is shown with the wheel 19 omitted. The profile of the lower corner 15 of the container 1 is cut away at an angle a at the base 5 and at an angle 3 at the end 13, wherein angle a is about 15 from the base 5 and angle f3 is about 45 from the end 13. The angled end and base portions meet at a point 14 located below and nearer to the end 13 than the axis of the wheel 18. By virtue of the angles provided, a maximum ground clearance may be achieved when the base 5 of the container 1 is angled to the ground at any angle within the range of 15 to 45 .

Referring now to Figures 5 and 6, a wheel cup in isolation is shown from perspective and side views, respectively. The wheel cup 21 comprises a single piece construction that is installed in a recess provided in a lower corner 15 of the container 1.

The wheel cup is preferably a metal casting but may be produced from any suitable material e.g. a plastic material. The wheel cup 21 is mounted in the recess such that it lies entirely within the profile of the container 1. The wheel cup comprises a main body portion 21a that partially contains the wheel 19 and a mounting flange that extends around an opening of the main body portion 21 a. The mounting flange features holes 27 that accommodate screws used to mount the wheel housing to the container 1. The wheel is rotatably mounted in the cup on axle 25. The mounting flange comprises three sections 21b, 21c and 21d. Section 21 b generally conforms to the base cutaway of the lower corner 15, section 21 c generally conforms to the end cutaway of the lower corner 15 and section 21d generally conforms to the end 13. The wheel axis is located above section 21b and inwards of section 21c at an angle y of about 400 to 450 to the vertical.

Referring now to Figure 7, the container is shown pivoted on its wheels, as would be the case when the container was being moved. The container is lifted using a handle 25 at the end opposed to the end at which the wheels 19 are mounted. The angle a is a relatively shallow angle so that only a relatively small angle of incline of the container 1 from the ground is required to give sufficient ground clearance for use on irregular surfaces and the angle 13 is a relatively steep angle to maintain such ground clearance at the extreme corner of the container if the container I is angled at a steep inclination angle. By virtue of this arrangement a single wheel cup 21 may be used with a range of cases of different sizes -a long container being inclined a smaller amount than a shorter case. Whilst it is preferable that the angles a and 13 are about 150 and 45 0 respectively so that a maximum ground clearance may be achieved when the case is angled between 15 0 and 450 to the ground, any suitable angles may be used.

Referring now to Figure 8, a perspective view of a container according to a second embodiment is shown. In this embodiment the container comprises a generally rectangular body 2 with the two opposite ends 13 being closed by detachable end covers 14. The container is preferably a "19 inch rack". In this embodiment the wheels 19 are arranged in a lower corner 15 of one of the detachable end covers. The arrangement of the wheel mounting and the lower corner 15 are identical to those of the first embodiment. r,s

Claims

Claims 1. A generally rectangular container having a base, a top, two

opposite sides and two opposite ends, the base and the ends defining rectangular envelopes at the lower corners of the container; wherein at least one wheel is mounted at one of the lower corners, the wheel being positioned entirely within the rectangular envelope of the base and adjacent end of the container.

2. A generally rectangular container as claimed in Claim 1, wherein the axis of the wheel is parallel to the lower corner at which it is mounted; the profile of the container is cut away at the corner; the axis of the wheel is located within the profile of the container; and the wheel extends outwardly of the profile of the container.

3. A generally rectangular container as claimed in Claim 1 or 2, wherein the lower corner of the container is cut away at an angle of about 15 at the base of the container.

4. A generally rectangular container as claimed in any preceding claim, wherein the lower corner of the container is cut away at an angle of about 45 at the end of the container.

5. A generally rectangular container as claimed in any preceding claim, wherein the wheel is mounted in a cup, which is fitted into a corresponding recess at the corner of the container.

6. A generally rectangular container as claimed in any preceding claim, wherein at least two wheels are provided.

7. A generally rectangular container as claimed in any preceding claim, wherein the container comprises a generally rectangular body with an open top closed by a lid, the base of the body and the lid being formed with stacking formations for stacking a plurality of such containers.

8. A generally rectangular container as claimed in any of Claims I to 6, wherein the container comprises a generally rectangular body with the two opposite open ends closed by detachable end covers, wherein the wheel is located in one of the end covers.

10. A generally rectangular container as claimed in any preceding claim, wherein the container is rotationally moulded from plastic material.

ii. A generally rectangular container having a base, a top, two opposite sides, two opposite ends and stacking formations protruding from the base and the top; wherein the base and the ends define rectangular envelopes at the lower corners of the container; the stacking formations are positioned entirely outside the rectangular envelope; and at least one wheel is mounted at one of the lower corners, positioned entirely within the rectangular envelope of the base and adjacent end of the container, such that when the container is placed directly on top of an identical container, the base of the container contacts stacking formations provided on a lid of the identical container, and the stacking formations provided on the base of the container contact the lid of the identical container.

12. A generally rectangular container as hereinbefore described with reference to, and as illustrated by, the accompanying drawings.