FI76475C - Fastener - Google Patents

Description

76475

The present invention relates to a fastening device for a shrub clearing device, by means of which and to which clearing chains are fastened to a rotating end, to a hub.

Nk. In a conventional embodiment of a shrub clearing device, there is a horizontally rotating head, i.e. a hub, formed by a substantially planar, circular plate mounted on a hydraulically driven shaft, usually with three chains attached to the head spaced 120 ° circumferentially and in use to turn out horizontally.

In known devices, attaching chains to said end has proved to be quite a problem. A device is known in which chains are threaded on a wire or steel rope with a hook or the like at each end. The second planar circular surface of the head has grooves that form an equilateral triangle with corners located on the circumference of the head. Said wire is intended to be placed in these grooves so as to form a loop at each corner to which the chain is attached and so that the wire remains in place in the grooves by means of two fixing pins fitted to the grooves to which said hooks are connected and by a cover covering the grooves.

In such a device, said pins and / or said loops break, often after a very short period of use, whereby one or more chains become detached. The considerable dynamic stresses that occur in use are concentrated in the structure shown for these elements. The loops are subject to e.g. a large number of bends due to forces in the circumferential direction of the head that move from the chain to the loop.

2,76475

The detachable chain can fly up to 300 meters and thus poses a great danger to the user or the public, as clearing work is often carried out near or along roads.

The present invention means a fastening head or a chain fastener by means of which the above-mentioned problems are completely ignored.

The invention therefore relates to a chain fastening device for a shrub clearing device, comprising in its plane a rotating head, usually formed by a circular plate, to which the chains, usually three in number, are intended to be fastened and from which they are intended to pivot substantially in said plane. the fasteners are intended to be fastened and are intended to be at least partially covered by a lid or the like.

The fastening device is characterized in that the head comprises three preferably similar grooves made in said plane, each groove opening at two points on the circumference of the head and extending as an arc, preferably forming part of the arc of the circle, between these points, each groove being fitted with a chain retaining ring. into protruding outside the perimeter of the head.

The invention will now be described in more detail with reference to the accompanying drawing, in which Figure 1 shows a head, hub according to the invention, from the side from which the chains with the fastening rings are brought to the end, one chain shown and the cover not shown, and Figure 2 showing section A-A of Figure 1.

In Fig. 1, 1 means a fastening head or hub belonging to the device, which is preferably formed by a circular plate 1, which is adapted to rotate in its own plane, for example by means of a central hole 2, in which a shaft (not shown) is intended to be placed against said plane.

n 3 76475

Said hub 1 comprises, in the event that three chains are to be fastened, three similar grooves 3 located substantially in said plane and evenly distributed on the circumference 4 of said hub, i.e. at 120 ° intervals. Each groove 3 opens at two points 5, 6 on the circumference 4 and runs as an arc 7, which preferably forms part of a circular arc 7, between the two points 5, 6.

A fastening ring 8 is arranged in each groove 3, which then partially protrudes outside the circumference 4. Figure 1 shows only one fastening ring 8. The fastening rings 8 are intended to remain in place in the grooves by the action of a cover 9 or the like, which cover is formed, for example, by a circular plate 9 placed in the cut 10 and intended to be fastened by through bolts not shown. The cover 9 is not shown in Figure 1 and in Figure 2 it is shown in broken lines.

The chain 11 can be fastened directly to the fastening ring 8, but according to a preferred embodiment, a clutch ring 12 is arranged to connect the ring 8 and the chain 11, which clutch ring then passes through the ring 8 and the loop 13 of the chain 11.

Likewise, according to the preferred embodiment, the cross-sectional shape of the grooves 3 and the rings 8, 12 is substantially square, as shown in Fig. 1.

The operation of the device according to the invention is obvious from the technical description presented above.

In the device according to the invention e.g. dynamic stresses and forces are retained without detrimental bending moments being transferred to the fastener. Experiments performed with the use prototype show that the service life of the fastening device according to the invention is many times higher than the known devices. The service life is also more than ten times that of the chains under normal conditions of use. The manufacturing cost of 4,76475 is approximately similar to that of known devices.

A few embodiments of the device according to the invention have been presented above. Of course, other embodiments and minor modifications are conceivable without departing from the spirit of the invention.

Thus, it is conceivable for said hub to consist of two substantially similar halves, which are, for example, connected to each other by bolts and between which said grooves 3 are formed. Each half then forms a "lid".

According to yet another and in some cases preferred embodiment, there are six grooves 3 for six chains, three grooves being located on one side of said hub, substantially as shown in Figure 1, and three grooves correspondingly located on the opposite side of said hub, and wherein the grooves are positioned so that the chains are substantially evenly distributed on the circumference of said hub.

According to a variation of this embodiment, the grooves 3, the chains, are arranged in groups, each group comprising two closely spaced grooves, one on the top side and the other on the bottom side, the division between the grooves in each group being less than 60 °, such as 50-55 °, and the division between the groups correspondingly greater than 60 °, such as 70-65 °.

The invention is therefore not limited to the embodiments described above, but can be modified within the scope of the appended claims.

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Claims (3)

5,76475 The patent claims A fastening device for chains of a shrub clearing device, comprising a head rotatable in its plane, preferably formed by a circular plate, to which the chains, usually three, are intended to be fastened and from which they are intended to pivot substantially in said plane, the end having grooves substantially in the plane to which it is fastened. are intended to be fastened and are intended to cover at least partially the lid or the like, characterized in that the head (1) comprises preferably similar grooves (3) made in said plane, each groove (3) opening at two points (5, 6) to the circumference (4) and runs as an arc (7), preferably forming part of a circular arc (7), between these points (5, 6), and in each groove (3) a fastening ring (8) of one chain (11) is placed, which then partially protrudes beyond the circumference (4) of the head (21). Device according to claim 1, characterized in that the chain (11) is intended to be connected to said fastening ring (8) by means of a clutch ring (12) passing through the fastening ring (8) and the chain link (13). Device according to claim 2, characterized in that the groove (3) and said rings (8, 12) have a substantially square cross-section.