FASTENING UNIT
Technical field of the invention
This invention relates to a fastening unit comprising two holding parts, each insertible in a respective seating or hollow space being provided with slits, said holding parts being interconnected by at least two spaced-apart links being articulatedly attached to the holding parts and sufficiently narrow to pass through said slits.
Short description of the inventive concept
The invention aims to provide a fastening unit, being particularly intended for locking cassette-shaped pontoons together although also useful for other purposes, which is simple to handle and achieves an efficient fastening of the pontoons or parts in question to each other. Accor¬ ding to the most characterizing of the invention this is achieved in that at least one of the holding parts comprises two spaced-apart blocks or halves being insertible, one after the other, in one and the same seating, each of said blocks or halves being connected to the other holding part by means of links and being interconnected by a force-transmitting element, particularly a bolt element, that can be accommodated in the same seating as its associated blocks, by means of which the blocks can be approached to respectively distanced from each other in order to on one 'hand, in a releasing position, keep the two holding parts at a comparatively large distance from each other and, on the other hand, in a fastening position, force the holding parts closer to each other whilst clamping two associated seatings against each other.
Background of the invention
A fastening unit of the general kind described introductorily is disclosed in DE-Al-2426080. However, in this device the holding parts in question are connected by a common bolt, localized centrally between two co¬ operating seatings. This bolt certainly can cause the
holding parts, and thus the seatings,to approach each other, but, due to the central position of the bolt between the holding parts, a movement of the seatings into a close engagement with each other is not possible.,
Brief description of the attached drawings
In the drawings Fig. 1 is a perspective view showing two pontoons being connected to each other by means of fastening units according to the invention, Fig. 2 is perspective view of a fastening unit according to the invention arranged to co-operate with two seatings in pontoons according to Fig. 1 and Fig. 3, and Fig. 4 shows side views showing the unit according to the invention in two different functional conditions.
Detailed description of a preferred embodiment of the invention
In Fig. 1 two cassette-shaped pontoons, denoted with 1,1', are shown that .can be locked to each other and, if desired, also to further similar pontoons, whilst forming a craft that can be used for different purposes, for instance for transports of different kinds or as a work platform, as a temporary ferry, a pontoon bridge, a lifting pontoon, a carrier, etc. In practice the pontoons can have the shape of a parallel-epiped and be manufactured of concrete, sheet metal or another suitable material. In order to make possible the interconnecting of the pontoons, square profiles 2,2', being provided with slits 3 along their entire length, are attached to, or moulded into, the two short sides of the individual pontoon and arranged in pairs. These profiles form hollow spaces or seatings wherein a fastening unit according to the invention can be received.
Reference is now made to Figs. 2-4 that illustrate the fastening unit according to the invention in detail. As can be seen in Fig. 2, the fastening unit, being in its entirety denoted with 4, comprises two holding parts
5,6 of which the last mentioned in turn comprises two mutually spaced-apart blocks or halves 7,8. Each one of the two blocks 7,8 of the holding part 6 is connected to the first-mentioned holding part 5 by means of a pair of links, 7 ',7" and 8',8" respectively, being swingably connected to the respective holding part by means of joints denoted 9,10.
The first holding part 5 includes two comparatively long side pieces 11,11', who at their lower ends are connected to each other by means of a bottom piece 12 and who at their upper ends are connected to each other by means of a cross-piece in the form of a pin 13 that, in practice, advantageously can be used for hanging the fastening unit on a lifting hook or similar. In practice the length of the holding part 5 can be only slightly less than the length of the above-mentioned hollow profiles 2,2'. The block 7 also includes two side-pieces 14,14'. These are interconnected by a first sleeve 15 that has been welded onto the outwardly facing longitudinal edges of the side- pieces in question. In an analogous way the lower block 8 also includes two side-pieces 16,16' interconnected by a second sleeve 17 which is internally threaded. A bolt element 18 extends through the two sleeves, having a head, for instance hexagon head 19, that can be engaged by a suitable tool for rotating the bolt. A collar 20 is arranged on the bolt below the upper sleeve 15. The - bolt 18 is provided with threads at its lower part and is threadedly engaged with the lower sleeve 17. The sleeve 15 is held between the collar 20 and the head 19 and is not in threaded engagement with the bolt element.
The function and advantages of the invention
In Fig. 3 it is shown how the fastening unit 4 has been inserted down into the two hollow profiles 2,2' with the two blocks 7 and 8 located at a certain, comparatively large distance from each other. In this condition the four links extend at a comparatively large angle to the
respective holding part, which means that the blocks 7,8 are separated from the holding part 5 with a pronounced space therebetween. In this condition the fastening unit can be inserted into the hollow profiles in a convenient manner, even if the profiles, respectively the associated pontoons, are not close to each other (it should in this context be pointed out that the distance between the blocks 7,8 and the holding part 5 can be made yet larger than shown in Fig. 3, namely if the links are swung essentially perpendicularly to the holding part 5 and the blocks 7,8 respectively).
After the fastening unit has been inserted into the hollow profiles 2,2', the bolt 18 is tightened in the way shown in Fig. 4, which means that thw two blocks 7 and 8 are approached to each other, which in turn means that the links successively are swung into a decreasing angle in relation to the holding part from which follows that the blocks 7,8 approach the holding part 5. When the bolt 18 has been tightened sufficiently, the blocks 7,8 and the holding part 5 are clamped with a great force against the slit-provided wall in the respective hollow profile thus achieving a close, immovable engagement of the hollow profiles 2,2' with each other. This means of course that the two pontoons 1,1' also are moved into a close, firm engagement with each other.
When the work has been finished with the craft composed of the pontoons, the pontoons can readily and simply be released from each other just by unscrewing the bolt 18 and pulling the fastening unit out of the hollow profiles in question.
Possible modifications of the invention It is evident that the invention not only is limited to the embodiment as shown in the drawings and described. Thus it is conceivable to use the fastening unit in question also for other purposes than just fastening pontoons together,
Individual details can of course be modified in many ways at an application of the invention in other fields of use. For instance other optional hollow spaces or seatings for receiving the fastening unit in question can be arranged instead of the hollow profiles.
Although it is preferred to connect the individual holding block 7 and 8 respectively to the associated holding part 5 by means of pairs of links that form a parallel link system ensuring that the blocks always are kept parallel to the common holding part, it is possible to connect the individual block with the common holding part by only one link instead of two. It is furthermore conceivable to use other power-transmitting elements than bolts, for instance a cylinder-piston mechanism. In this context it should be pointed out that an approach of the two blocks towards the common holding part can be achieved not only by approaching the two blocks against each other but also by distancing the blocks from each other. Although the pontoons only have been illustrated and described as having seatings in their short sides, their long sides of course also can be provided with seatings, thus allowing a side by side relationship of the pontoons as well.