GB2346928A

GB2346928A - Cargo conveyor with means to stiffen the mountings of securing latches

Info

Publication number: GB2346928A
Application number: GB9926111A
Authority: GB
Inventors: Thomas Huber
Original assignee: Telair International GmbH
Current assignee: Telair International GmbH
Priority date: 1998-11-24
Filing date: 1999-11-05
Publication date: 2000-08-23
Anticipated expiration: 2019-11-05
Also published as: FR2786157A1; GB9926111D0; FR2786157B1; GB2346928B

Abstract

A cargo conveyor 10 for an aircraft comprises a U shaped conveyor fitted with a plurality of rollers 21 and at least one latch claw 30. Roller 21 are fixed to side walls 11, 12 of the conveyor to form a box shape, providing additional stiffness. The one or more claws 30 may be mounted on side support elements or "cheeks" 33. The cheeks 33 provide greater stiffness to the mountings of the latch claws 30; the cheeks 33 may be changed to suit the load or weight of the cargo in order to give optimum stiffness and stability and minimum weight to the conveyor 10. The cheeks 33 may be attached to the inner or outer side walls of the conveyor. The axles of claws 30 are provided with bearing bushes which connect the side cheeks 33 and side walls firmly to one another (figure 4).

Description

2346928

Latch element DESCRIPTION

The invention relates to a latch element for securing containers or similar cargo on the floor of the cargo space in an aircraft.

The German patent DE 42 24 820 C I discloses a latch element of this kind, which comprises a U-shaped frame that can be attached to the floor of a cargo space by means of special connecting elements. The weight of such a latch element is relatively great. The reason is in particular that the frame, which has a relatively complicated shape and is expensive to manufacture, is ordinarily so designed that the latch element can be universally employed. That is, it can be used both at sites where very large loads are imposed as well as at much less heavily loaded sites. In the latter case, although the frame of the latch element is overdimensioned, it would be too expensive to provide special frames for such lower-load purposes.

The object of the invention is to disclose a latch element for securing containers or similar cargo on the floor of the cargo space in an aircraft that while having minimal weight exhibits the greatest possible stability, which in particular is adjusted in accordance with the load to be supported. This object is achieved by provision of the following elements:

at least one roller conveyor that can be mounted in or on the cargo-space floor and is substantially U-shaped in cross section, with side walls and a bottom; at least one latch claw, which is fixed within the roller conveyor so as to be pivotable about at least one claw axis.

This construction makes it possible to use the roller conveyor, which is provided in any case, simultaneously as a mounting frame for the latch claws.

For cases in which increased stability is demanded, it is advantageous for additional side cheeks to be installed, to which the latch claws are fixed.

2 An additional increase in stability can be achieved by mounting the rollers in the roller conveyor so that the latter is stiffened, by converting its basic U-shaped profile into a box shape, which substantially increases the overall stability of the arrangement. This is also achieved by the bearing bushes to support the claw axles, which are so constructed that they firmly connect the side cheeks and the side walls to one another.

Preferably the side cheeks are disposed within the roller conveyor, against the inner surfaces of its sides. As a result, the outer dimensions of the roller conveyors and hence their assembly dimensions are not increased.

Preferably the side cheeks are attached to the side walls so that they mak6 contact therewith over a large area. This arrangement optimizes the increase in stifffiess or stability of the side walls that is brought about by the side cheeks.

The side cheeks preferably comprise a plurality of bores for connection to the side walls, and these connections preferably are achieved by way of rivets, which considerably facilitates installation while only slightly adding to the weight.

The bearing bushes preferably comprise sheaths with stop elements near their ends, which can be placed under tension so that they are forced together with a side cheek and side wall interposed between them. This measure ensures that although the thicknesses of the side walls and the side cheeks are relatively slight, no bulging is produced at the bearing bushes even when relatively large loads are imposed on the latch elements. In this arrangement, preferably at least one stop element of each bearing bush is constructed as a tensioning element and is removably attached to the sheath. A simple and secure fixation is thus made possible. The tensioning element in a preferred embodiment comprises a threaded ring, which is connected to a nut or similar tensioning piece that can be gripped by a tool, by way of a preformed breaking site that allows the nut be separated from the threaded ring if a predetermined tightening force is exceeded. Break-off nuts of this kind are known per se. In the present case their use is especially advantageous because it enables rapid and simple installation of the latch elements. The other tensioning element is preferably fixedly connected to the sheath, in particular integral therewith, and comprises engagement surfaces with which a tool can be engaged, which are used when the threaded ring is 3 to be released or screwed off. By this means a very simple exchange of the bearing bushes is made possible.

The side cheeks preferably have a thickness andior a shape corresponding to a maximal load expected to be imposed on the latch element at the site where it is installed. Thus by simply exchanging the side cheeks according to the site at which the apparatus is to be used, the stability can be made optimal, which in turn allows a maximal weight reduction.

Preferred embodiments of the invention will be apparent from the subordinate claims and the following description of exemplary embodiments, which are explained with reference to drawings, wherein

Fig. I shows an embodiment of a roller conveyor with double latch claws drawn in perspective, one installed in and one removed from the conveyor, Fig. 2 is a drawing Re that of Fig. 1, but with all latch claws installed, Fig. 3 is a drawing like that of Fig. 1, but showing latch claws separate from the conveyor and attached to side cheeks, Fig. 4 is a perspective, exploded view of a roller conveyor with side cheeks in place and uninstaEed bearing bushes.

In the following description, the same reference numerals are used for identical parts or parts with identical actions.

In the embodiments of the invention shown in Figures 1, 2 and 3 a roller conveyor 10 with substantially U-shaped cross section is provided, which comprises a first side wall 11, a second side wall 12 and a bottom 13. To reinforce the side walls 11, 12 their upper edges are bent outward, the roller conveyor 10 preferably being constructed as an extruded (aluminium) profile.

In the roller conveyor 10 are mounted rollers 20, which comprise a roller body 21 and roller axles 22. The roller axles 22 are fixed within the roller conveyor 10 by way of 4 screw connections at their ends, in such a way that the side walls 11, 12 are connected to one another through the roller axles 22 so as to form a stiff box profile.

Latch claws 3 0, 3 0' are provided, which in a manner kown per se are so mounted, by way of arms 31, 31' on claw axles 32, 32', that they can be pivoted about the claw axes 32, 32'. The springs for pivoting, and the locking means that serve to hold the latch in its rotated-upward position (Figs. 1-3) or in its retracted position (not shown), are not shown here in detail because they are known per se, for example from the patent DE 42 24 820 C I cited above.

In addition, side cheeks 3 3, 3 3' are provided, which comprise a plurality of rivet bores 34 by way of which the side cheeks 33, 33', when placed in contact with inner surfaces of the side walls 11, 12, are riveted thereto.

The claw axles 32, 32' are rotatably seated in bearing bushes 35, which preferably are constructed substantially as is known from the German patent DE 42 15 715 C2. These bearing bushes 35 each consist of a sheath 36 which comprises at its one end, situated in the interior of the roller conveyor 10, a flange-shaped stop element 41 and at its other end a threaded section. Onto diis threaded section of the sheath 36 can be screwed tensioning elements 40 comprising a threaded ring 39 connected to a breakoff nut 37 by way of a preformed breaking site 38. For assembly, the sheaths 36 are inserted through bores in the side cheeks 33, 33' and corresponding bores in the side walls 11, 12 until their stop elements 41 are seated against the side cheeks 33, 33'. Then the threaded rings 39 are screwed on and the break-off nuts 37 are tightened until the preformed breaking sites 38 give way an d the break-off nuts are removed. The preformed breaking sites 38 are so dimensioned that a tightening force sufficient for long-term load-bearing is ensured. For disassembly the stop elements 41 can be gripped with pliers and turned so that the threaded rings 39 become released from the bearing bushes 35. Then a new bearing bush 35 can be inserted in a simple manner.

This modular construction of the latch element with exchangeable side cheeks 33, 33' makes it possible to undertake a minimal dimensioning such that for each desired application, the latch elements have the necessary stability while the weight of the arrangement as a whole is minimized. This stability can be achieved by a suitable choice of both the thickness of the material of which the side cheeks 33, 33' are made and their shape (for simplicity, only planar surfaces are shown here). The most problematic place with regard to loading is the site at which the bearing bushes 35 are disposed. Because these bearing bushes 35 are fixed firn-Ay under tension in such a way that the side cheeks 33, 33' are pressed against the side walls 11, 12, an especially great stability is achieved.

Furthermore, the multiple rollers 20 and their axles 22, as shown in particular in Figures 2 and 3, also bring about a considerable stiffening of the roller conveyor 10. Nevertheless, the arrangement is simple to assemble and disassemble.

It will be evident from the above that in a single roller conveyor 10 a plurality of differently "strong" individual latch elements can be mounted quite simply by installing side cheeks 3 3, 33' of different thicknesses, depending on the site.

6 List of reference numerals Roller conveyor 11 First side wall 12 Second side wall 13 Bottom Roller 21 Roller body 22 Roller axle 30, 30' Latch claw 31, 3 V Arm 32, 32' Claw axle 33,33' Side cheek 34 Rivet bore Bearing bush 36 Sheath 37 Break-off nut 38 Preformed breaking site 39 Threaded ring Tensioning element 41 Stop element I 7 Latch element

Claims

I. Latch element for securing containers or similar cargo on the cargospace floor of an aircraft, comprising - at least one roller conveyor (10), which can be installed in or on the cargospace floor and has a substantially U-shaped cross section with side walls (11, 12) and a bottom (13), and - at least one latch claw (30, 30'), which can be fixed within the roller conveyor (10) in such a way as to be pivotable about at least one claw axle (3 2, 3 2');
2. Latch element according to Claim 1, characterized by - a plurality of rollers (20) that are rotatable about roller axles (22) the ends of which are fixed in the side walls (11, 12) of the roller conveyor (10);
3. Latch element according to Claim I or 2, characterized by - at least one pair of side cheeks (33, 33'), which can be attached to inner surfaces or outer surfaces of the side walls (11, 12); 8
4. Latch element according to Claim 3, characterized by bearing bushes (35) to support the claw axles (32, 32'), which are so constructed that they connect the side cheeks (33, 33') and the side walls (11, 12) firmly to one another and are held in both.
5. Latch element according to one of the preceding claims, characterized in that the side cheeks (33, 33') of the roller conveyors (10) are attached to the inner surfaces of the side walls (11, 12).
6. Latch element according to one of the preceding claims, characterized in that the side cheeks (33, 33') are in contact over a large area with the side walls (11, 12) and are fixed to the latter.
7. Latch element according to one of the preceding claims, characterized in that the side cheeks (33, 33') comprise a plurality of bores (34) for connection to the side walls (11, 12), preferably by way of rivets.
8. Latch element according to one of the preceding claims, characterized in that the bearing bushes (35) comprise sheaths (36) with stop elements (40, 41) near their ends, which can be forced towards one another under tension with a side cheek (33, 33') and a side wall (11, 12) interposed therebetween.

I
9 9. Latch element according to Claim 8, characterized in that at least one stop element of each bearing bush (35) is constructed as tensioning element (40) and is releasably attached to the sheath (36).
10. Latch element according to Claim 9, characterized in that the tensioning element (40) comprises a threaded ring (39) that is connected by way of a preformed breaking site (38) to a nut (37) or similar tensioning piece that can be gripped with a tool, which can be separated from the threaded ring (39) when a predetermined tightening force is exceeded.
11. Latch element according to Claim 10, characterized in that oen of the stop elements (41) is fixedly connected to the sheath (36), in particular is integral therewith, and comprises engagement surfaces to which a tool is applied for loosening or unscrewing the threaded ring (39).
12. Latch element according to one of the preceding claims, characterized in that the side cheeks (33, 33') have a thickness and/or shape that corresponds to a maximal load expected to act on the latch element.