NL1006816C1 - Guard ring for fitted around mower head to prevent it from striking hard objects - Google Patents

Abstract

Ring size can be altered in at least one direction when fitted around a cornerless shape mower head, whilst at least two of its sides are length adjustable when fitted around a polygonal shaped mower head, the angles between the sides of the ring optionally being variable in order to carry out the length adjustment. The ring can be dismantled into two or more sections (4, 5), one of which is raisable away from the mowing surface and joined both to the mower and the other sections. The entire ring can be moved upwards along the mower or the hollow tube (1) housing the mower drive mechanism. The ring is spring-loaded (10) so that when a lifting force is released it automatically returns to the mowing surface. A cover (11) is provided over at least part of the top side of the ring. The manually-operated mower can be carried on the back and utilises a mower mechanism consisting of a circular saw, brushes or blades (2) that rotate at high speed. The hollow tube housing the mower drive mechanism is held by the mower operative during use. The ring guard is placed level with, above or below the mower mechanism plane to form a rigid border around the periphery of a polygonal (e.g. rectangular or octagonal) or cornerless (e.g. circular or oval-shaped) mower head.

Description

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Protection for brushcutters

The invention relates to the field of manually operated, portable mowers, also known as brushcutters.

This type of mower is usually carried on the back, with the mowing mechanism at ground level, in front of the carrier, and with the drive shaft in a hollow pipe, which is held by the carrier and with which it controls the mower. The mowing mechanism usually consists of a circular saw, or a number of blades 10 (also called percussion blades) or brushes, which must rotate at a high speed.

This type of mower is intended for weeding, mowing and harvesting weeds, light bushes and small trees. An important problem is that the mowing mechanism damages all things in the mowing path, including the trees that do not have to be cleared or embellishments and structures such as fences, fences, etc. Moreover, the strength of, for example, knives is so dangerous to people and animal.

This invention solves this problem by providing the mowing mechanism with a protective ring, which has a slightly larger diameter than that mowing mechanism.

However, such a ring immediately causes a number of new problems.

25 - The ring prevents the mowing mechanism from mowing along walls, in gutters, etc.

- In addition, with smaller trees that need to be grubbed up, the trunk is inaccessible to the mower blades, because the ring hits the trunk.

- A final problem is the variety of diameters of 30 cutting mechanisms, all of which can be placed on the same mower. One must then choose from as many rings or a single large ring, which protects the largest diameter. The first choice is impractical, while the second choice creates a distance between the edge of the mowing circle of smaller mowing mechanisms and the ring (after all, it has a larger diameter), which only increases the first two problems.

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This invention solves these problems by making the ring adjustable in diameter and partially folding at the front. As a result, the ring is always as much as possible the same size as the mowing mechanism and yet any growth with the mower is accessible.

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The ring also offers the possibility to easily protect the carrier against clippings thrown up by the mowing mechanism, by (partially) covering the ring at the top.

10 No patents are known of comparable findings.

Advantages of the invention are: - Protection of things that should not be hit by the mowing mechanism, such as fences, trees and of course people and animals.

15 - Remaining accessible despite the ring for the mowing mechanism of small trees and vegetation in gutters and along or against walls and buildings, etc.

- Due to the diameter (partly) adjustable ring, the front of the ring can be given an almost equal diameter as the mowing mechanism, so that vegetation and the like are more accessible to the mowing mechanism.

- By adjusting the diameter of the ring in this way, the ring also gives the wearer a good visual indication of the edge of the operating mowing mechanism, so that the wearer can mow more accurately and precisely.

25 - (The possibility of) protection of the carrier against raised grass clippings.

Below follows a description of a possible implementation of the invention. Figure 1 is a perspective view of the end of the hollow pipe of a brush cutter, with a cutting mechanism consisting of blades attached to it, provided with the described protection ring in folded down (neutral) position. The ring shows two differently set diameters and is also partly equipped with a cover.

Figure 2 shows the same combination as Figure 1, but now with the ring folded up and the tree to be cut away, so that it is immediately clear that the ring must be foldable in order to make the tree accessible for the mowing mechanism.

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The ring consists of two parts - a front half (3) and a rear half (4) - and is attached at different points (5) to the hollow pipe (1) of the brushcutter by the rear half (4), at equal height or slightly higher than the mowing surface of the mowing mechanism (2), in this case percussion blades. The front half (3) is rotatably attached to the rear half (4) at both points (6), in such a way that the front half can only be turned upwards (folded up) (13) in part (maximum perpendicular). the back half (4). However, the mounting (6) can be locked in the neutral position (12) - in which the two halves (3, 4) form a flat surface - to prevent the front half (3) from folding up unintentionally. 10 Here, the locking simply consists of a screw that can be tightened (14).

The diameter of the ring can only be changed in one direction, because the distance from the front point of the front half (3) to the rear point of the rear half (4) can be adjusted over a limited length. This is achieved here in that the two ends of the front half (3) are extended and are provided with a threaded end (7), which is inserted into a sleeve (8), which is mounted on the rotatable mounting (6), so that part of the threaded end (7) protrudes on both sides of the sleeve (8). A nut is attached to the threaded end (7) on both sides of the sleeve (8) and by tightening both nuts from each threaded end (7) 20 to the respective sleeve (8), the front half (3) is secured the back half (4). By turning both nuts of each threaded end (7) in the same direction, the threaded ends (7) (and thus the front half (3)) can be secured at different distances - measured from the end of the threaded end (7) - in relation to the bus (8). The length of the threaded rods (7) determine the length over which the diameter of the ring is adjustable in one direction in this way (9).

At least one of the two attachment points (6) is provided with a tension spring mechanism (10), one end of which is attached to the rear half (4) of the ring and the other end to the front half (3) of the ring, such that that the spring mechanism (10) is untensioned when the ring is in neutral position (12). As a result, in the absence of an upward force, the upwardly folded (13) front half (3) will fold down again into the neutral position (12).

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The rear half (4) of the ring is fitted with a cap (11), which covers the cutting mechanism (2) at the top.

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Possible alternatives of this embodiment are limited to the various options for or omitting a) tiltable ring half, b) (partly) adjustable diameter of the ring, c) automatic folding of the tilting ring half into neutral position and d) the hood.

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Regarding d), a cap, which must cover the entire ring at the top, will preferably be partly transparent (e.g. fine mesh), to maintain a view of the work, and consist of 2 parts, so that each ring half has its own cap . The hood of the front half will cross over at the rear and partly fall over the hood of the rear half. At the height of the tilting line, the front hood must have a flexible part in order to be able to bend in different positions: the tilting line is not fixed relative to the front, adjustable half. Of course, ring and cap can form one whole.

A natural alternative to b) is to provide the ends of the front half (3) with an equal number of connection options at mutually equal distances for attachment and securing at a designated connection point on the rotatable mountings (6). A good example is a combination of a sleeve on the rotatable mounting (6) through which the end fits, with a lockable wedge connection with a number of holes intended for this purpose at equal distances in the end.

A somewhat more complicated alternative to b) is, for example, an octagonal frame, with a straight front, which front is adjustable in length, wherein both sides of the frame are also adjustable in length and are hinged to the rear of the frame. This means that almost the entire frame can be adjusted in diameter, so that the contours of the round cutting surface can be followed more precisely. Ideally, both hinged points are spring-mounted in such a way that the sides of the frame permanently have a force directed towards the center of the mowing surface and thus strengthen the securing of the frame.

Furthermore, the function of folding up the protection - the (partial) lifting of the protection of the mowing surface - can also be achieved, for example by making the entire ring shape movable upwards along the hollow pipe, by means of e.g. slide mechanism fitted to the pipe (possibly with spring force directed downwards (to the neutral position).

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Claims (3)

1. Protection for handheld, portable motor mower (also called brush cutter) - which mower is usually carried on the back, with the 5 cutting mechanism (usually consisting of a circular saw, brushes or (impact) blades, which serve at a high speed round rotate) at or just above ground level, in front of the carrier, with the drive shaft in a hollow pipe, which is held by the carrier and with which it controls the mower - as used and intended for weeding, mowing and harvesting weeds, light 10 scrub and small trees, which protects the cutting mechanism from all those things that should not come into contact with the cutting mechanism, because the protection is placed at the same height or slightly higher or lower than the cutting surface (the surface of the rotary cutting mechanism) and at least follows the outer edge of the mowing surface and thus forms at least a polygonal or angular frame or framework with at least the same surface and / or the same d as large as the mowing surface, which frame is rigid and sturdy enough to withstand impacts from hard, heavy and impact-resistant objects while using the mower, characterized in that the size of the protection - that is, the surface to be protected - is repeatable and locking hair is adjustable because when the framework is angular (circle, oval, etc.) it can be enlarged and / or reduced in at least one direction (such as, for example, oval longer / wider or circle to oval), and because when the framework is multi-sided (square, octagon, etc.), this has at least two sides that can be lengthened and / or shortened, where the angles between the other side (-n) and / or the sides to be adjusted can be changed to allow the length change to be possible ; that the protection is at least partially liftable, because either a part is movable upwards from the mowing surface to the rest of the protection or the mower is attached, or the entire protection 30 is movable upwards along the mower or the hollow tube, which lifting preference is of a temporary nature, because a force is constantly exerted on the part or whole, which, when the force is lifted to move the part or the whole upwards, returns that part or whole to the original position relative to the mowing surface in which it protects the protected functions and in which the part 35 forms one plane with the rest of the protection, in which protection-providing position the part or the whole can preferably be secured; 1 0068 1 6 that the protection preferably also offers protection in an upward direction, because the frame is preferably at least partially shielded at the top, when the frame fulfills the protective function, which shield (or cap) optionally forms a whole with the frame . 5 Protection according to claim 1, characterized in that the frame all around, at a small distance outside the outer edge of the mowing surface, has a skirt, which may or may not be removable, which provides additional protection, which ends lower than the mowing surface. 10 Protection according to claim 1 or 1 and 2, characterized in that the protection comprises only parts of the combination described in the previous claims, such as an exclusively size-adjustable protection, a only folding protection, an adjustable folding protection without shielding, etc. 1006816