DE892391C - Mechanical hedge trimmer - Google Patents

Description

l. P. 175) ISSUED OCTOBER 8, 1953

St 3666IH / 45 f

The invention relates to a mechanical pick cutter with a fixed, A base plate rotatably arranged on one side with finger-like projections and 'consists in that the cutting edges of the finger-like projections run parallel and cut the circle of the wing knife at different angles.

In the known hedge trimmers with over

ίο the sharpened teeth of a base plate rotating wing knife, the position of the cutting edges of the knife and the teeth to each other is constantly the same during the cutting process. Likewise, the size of the interacting cutting edges always remains the same for each individual cutting process. The wing knife therefore theoretically has to overcome the same resistance in each tooth gap when cutting the shrubbery.

This means that the effect of the inertia force of the Flügehnesser at the first tooth gaps on strongest, but in the last tooth gaps it is so small that pulling through the wing knife is endangered by all gaps between the teeth covered with shrubbery and blockages can easily occur can. One has therefore mostly switched to making the wing knife particularly heavy or with long ones To train arms or to install a flywheel. This can cause the Can be corrected, but not its cause.

But if the force given to the wing knife by its drive is increasing and decreasing Dimensions during the cutting process is claimed, with the greatest decrease in force is roughly in the middle, the aforementioned disadvantage can also be caused by a lighter design of the

The hedge trimmer. According to the invention therefore the cutting edges of the teeth are at different angles to the Set the cutting edge of the rotating wing knife and / or the tooth gaps for the area of action of the wing knife staggered accordingly.

In the drawing, the invention is shown in one embodiment, namely illustrated

ίο Fig. ι a symmetrical longitudinal section through the hedge trimmer,

Fig. 2 a cross section along line AA of Fig. I,

Fig. 3 a cross section along line CC of "x5 Fig. 2 (execution of the cutting edges of the fingers ii),

Fig. 4 View of the wing knife (elevation) and

Fig. 5 View of the wing knife (plan to

Fig. ₄ ),
Fig. 6 a cross section along line DD in Fig. ₅ :

In a housing ι with foot 2 is the horizontal Drive shaft 3 and the vertical impeller shaft 4 supported in ball bearings. At the bottom of the

Shaft 4 sits the wing knife 5, which can be tightened by a nut 6. The wing knife 5 slides over a base plate 7 which, by means of countersunk screws 8, is attached to the foot 2 of the housing · 1 is attached. On the top of the shaft 4

sits a worm wheel 9 which is in engagement with a worm 10 dm attached to the drive shaft 3.

The base plate / has parallel fingers ii on the shear side, which are opposite to the direction of rotation

of the wing knife are provided with cutting edges. The fingers 11 have the task of Pick up shrubbery and guide it in front of the circling wing knife 5. As can be seen from Fig. 2, is the free cross-section between the individual ones covered by the "rotating wing knife" Pairs of fingers in the outer pair of fingers less than in the middle pair of fingers. Furthermore is the angle between the cutting edges of the knife and the fingers, on the outer fingers large and diminishes after the middle fingers to the acute or most acute angle. The one to be expended Cutting force is within the first pair of fingers (in the direction of rotation of the wing knife seen) least, because here only shear forces come into play and to the others the shrubbery can still evade. In the middle pair of fingers, on the other hand, are the Cutting at the most acute angle, and the wing knife has to exert the greatest pressure here. The knife then has a mandatory bevel cut position between the subsequent pairs of fingers as well as decreasing amount of shrubbery in front of you, so decreasing force decrease.

The base plate 7 has no protruding parts on its underside, so that the tips of the cut shrubbery underneath the cutting device. For this purpose, the base plate 7 is also provided with inclined run-out surfaces 12 between the roots the finger 11 is provided.

The cutting apparatus is provided with a hood 13 to protect the moving parts and the operator. As the drawing illustrates, the apparatus can be coupled directly to a motor 14 and held by the handles ¹ S. ^τ 5 ' . The shaft 3 can, however, also be coupled to a flexible shaft, and the housing 1, which then receives the connecting piece for the flexible shaft, can be designed as a handle.

Claims (4)

Patent claims: 1. Mechanical hedge trimmer with one over a fixed one on the cutting side base plate provided with finger-like projections rotatably arranged wing knife, characterized in that the cutting edges of the finger-like projections are parallel run and cut the circle of the wing knife at different angles. 2. Hedge cutter according to claim 1, characterized in that the wing knife circle covers the middle fingers more than the outer ones. 3. Hedge trimmer according to claim 1 and 2, characterized in that the underside of the base plate has no protruding parts. 4. Hedge cutter according to claim 1, 2 and 3, characterized in that the base plate (7) is provided with inclined run-out surfaces (12) between the roots of the fingers (11). ■ 1 sheet of drawings © 5462 9.5?