DE1030095B - Pruning shears - Google Patents

Description

GERMAN

The invention relates to pruning shears, in particular for cutting branches and saplings, in which a curved cutting knife is moved against a fixed hook and through a appropriately designed leverage with little effort exerted great cutting forces can be. This makes it possible, even by untrained workers with the necessary Safety measures to carry out all cutting work on trees, shrubs and plants.

To carry out this cutting work are the best known and most common so-called pruning shears, which with simple lever transmission and proportionately long cutting knives can easily cut through thin branches and saplings that but are no longer sufficient for cuts that require greater forces. To such pruning shears To make it more suitable for inoculating work in particular, the fulcrum of the leaf-shaped Cutting blade placed eccentrically to the pivot point of the scissor handles, the extension of one Grip engages beyond the main pivot point on the leaf-shaped cutting blade in an elongated slot and thus results in a pulling cut, which is especially useful when cutting branches and saplings important is. Even if this has partially improved the usual pruning shears, they are thus possible cutting forces in many cases too low to remove thicker branches and saplings from the Separate main stem.

Cutting tools, in particular scissors, are now known which are positioned between the actuating levers and the cutting edges have more or less strong translations in order to exert great cutting forces to be able to. However, these scissors have the major disadvantage that the resulting large cutting forces at the expense of the opening angle of the scissors, d. H. that these scissors, mostly for cutting of sheet metal, cables and the like are used, 4c are unsuitable as pruning shears, since they only use branches and saplings of relatively small diameters can be cut.

The invention, however, has a pruning shears as an object, which the two main requirements a pulling cut and a corresponding increase in force if the opening angle is sufficient Fulfills. This is done in detail in that the between the movement lever and the cutting knife Activated power transmission via two pivot points lying one above the other and one between them lying, attached to the cutting knife takes place, the so incorporated in the lever Long slot swings so that its upper

Applicant:

Alfred Giesser,

Winnenden near Stuttgart, Marktstr. 12th

Alfred Giesser, Winnenden near Stuttgart,
has been named as the inventor

limit forms the stop for the two end positions of the scissors. The pivot points of the cutting knife and the movement lever lie on the part of the hook which is enlarged to form a plate, and the cutting knife slides on the surface of this plate against which it is held by part of the lever. At this The arrangement and power transmission result in a pulling force if the opening angle of the scissors is sufficient Cut of the curved cutting knife against the fixed hook and with the appropriate design and lengthening the operating lever ratios that meet all cutting requirements branches, saplings and all other inoculating work is sufficient. The curvature of the Fixed hook gives at the same time the security that the cross-section to be cut is firmly in the scissors area and is pressed inward by the cutting knife moved against it. It is also a guarantee given that neighboring parts of the tree or shrub are not injured by the knife will.

For more convenient operation, the operating handles are opposite the plane given by the plate angled upwards so that it is possible to work in an upright position, which in turn is less Means exhaustion of the operator's strength. The handles or levers are expedient provided with covers made of elastic material, which reduces the risk of blistering on the hands of the operator. Finally, it is important for the durability of the scissors that According to the invention, the vibrating cutting edge made of a particularly resistant material, for. B. made of special steel.

In the drawing, an embodiment of the invention is explained, namely shows
Fig. 1 is a plan view of the scissors,
Fig. 2 is a side view of the scissors and
3 shows a schematic representation of the lever transmission.

809 510/67

Il 030

The fixed part of the scissors is denoted by α , with the cutting edge a! is bent like a hook. This hook a ' is extended to a plate a' ″ in which the pivot points e and f lie. The movable cutting knife b is mounted in the upper pivot point e , while the two-armed lever c moves around the pivot point / the two-armed lever c in its upper part c ' a recess c'", e.g. B. an elongated slot 'is arranged'. A pin d connected to the knife b engages in this recess c '" , so that when the handle c is moved, the knife b is entrained. In the case of the fixed part α , the plate a!" in the upwardly bent handle a ″ and the two-armed lever c in the likewise cranked handle c ″ . These handles a ", c" are expediently provided with a casing g, which can consist of rubber or another suitable material. The elongated slot c '" located in part c can also be covered on the outside either by a special plate or by the wall that has not been milled through at this point.

The pin d of the cutting knife b , swinging around the point e , moves on the circular arc h when the scissors are opened or closed, while the point 0 of the elongated slot c '"selected as an example describes the circular arc i . The intersections of the two circles h and i result the end positions of the cutting blade B in the semi-closed position of the blade b, the pin comes to lie d p to the point, resulting for the three main positions - fully open, half-closed, fully closed scissors - following lever ratios..:

Open and closed position
P · k = Q · I and further
Q m = R- η

Middle position

P ■ k = Q ■ ΐ and further

Q ■ m - R ■ n.

40

Due to the lever arm / 'reduced in the middle position / », the force Q will be greater at this point than in the two end positions. Over the entire path of the cutting knife b , however, the muscle force P up to the cutting force R is multiplied at every moment.

Of course, in the context of the invention, as already indicated earlier, instead of the force transmission through pins and elongated slots, one can also use toothed segments on parts b and c . The embodiment is particularly useful in that the cutting knife b as part

35 made for itself and therefore made of the best special steel! can exist, which increases the service life of the scissors considerably. In terms of application, the fj Do not shear in any way on the examples given limited. It can be organic and anofga * '"! niche fabrics of all kinds, such as leather, linoleum, !! Rubber or buna plates or strands, braided ^ !! or woven fiberboard, strong cardboard, kurzuaj | all non-metallic, but flexible materials ^ get cut. i |

Claims (5)

Claims:, | 1. Pruning shears, especially for cutting branches and saplings with an ulcer! genes cutting knife against a solid Häfeerx | is moved, characterized in that the | j between the movement lever (c) and the detail cutting knife (b) switched on force transfer ^ ¹ ^ zung over two superimposed pivot points;! ::! (e, f) and an anffj cutting knife (b) attached between them and a driver pin (rf); | takes place, which is carried out in one of the lever (c) ^! || The left long slot (c "') swings so that its upper limit forms the stop for the two end stops of the scissors 2. Pruning shears according to claim 1, characterized in that || indicates that the pivot points (e, f) dBs | Cutting knife (b) and movement lever (c)! lie on the part of the | hook (ei ') expanded to form a plate (a'") and that the cutting knife (|?) |. slides on the surface of this plate (a '") against "! which it from the part ( c ') of lever (c) is held; | 3. Pruning shears according to claim 1 or 2, daidürÄ: i: characterized in that the handles (a ", c") ^ J! the plane given by the plate (a '") , n ^
are angled at the top. ;. ', i ::: | 4. Pruning shears according to one of Anspri | ■ felJei to 3, characterized in that the vibration ii constricting cutting edge (b) of a particularly ¹ ^ of ¹ -; "stand-wearing material, for example from probe ^ i $ l?. | Ii *! Is established. ■, -; ■. | 5. Pruning shears according to one of claims 1 ;; - to 4, characterized in that the handles ;-( α ", c") are provided with coatings (g) made of elastic material J ₁ '. ^:: ' Documents considered: ■ '': j German Patent Nos. 106,629, 382,890; }. German utility model No. 1 699 187; : French Patent Nos. 502 432, 673 954; _^::. USA. Patent Nos 1,553,039, 1,666,832 ,: ί 647 312.: i 1 sheet of drawings © 809 510/67 5.