SU730329A1 - Apparatus for timber cross cutting - Google Patents

Description

scheme of action of force on the wood when cutting.

The device for transverse cutting of wood includes two parallel socks 1,2, which are interconnected by means of bolts 3 and plates 4, which have openings 5 at the ends for connecting the device to forest machines or aggregates. Each knife is made with a one-sided sharpening, with the edges b of the knife sharpening facing one another, and the value a, the offset of the blades is 0.01-0.35 cutting width, each knife being made with a double undercut 7 relative to the edge of its sharpening. The undercut on a knife displaced in the cutting direction, facing the other knife, partially overlaps the edge of sharpening the latter by a value equal to 0.025-1.0 of the width b of the cut.

A device for transverse cutting of wood works as follows.

With its cutting edges, the device slides onto the wood across its fibers. In this case, the offset knife 2 (Fig. 3) first deforms and cuts the wood fibers, then the knife 1 cuts these fibers from the other end with some delay and at the same time presses its sharpening edge b on the cut part of the wood,

In the process of cutting, a force P arises on the cutting edge of knives, a force R. on the front cutting edge. Slices 8 of wood in the process of pulling the device through the space between the knives. Since the edge of the sharpening of the knife 2 is shifted by an amount a, the slices 8 of the wood of the fillings rotate in the direction of the moment M created by the force P of the edge of the sharpening of the knife 1. By this the fibers of the wood of the slices 8 are oriented in the direction of the cutting. In addition to turning, the cut part of the wood additionally cleaves along the fibers, as a result of which the height of the slices of the cut part is less, which is the gap between the knives, and thus the cut part of the wood is moved between the knives without significant resistance.

The impact of sharpening b faces on wood with an effort P can lead to chipping of the tree trunk, however, due to the fact that these faces are facing one another (Fig. 2), these chips do not extend into the business part of the trunk.

When felling trees, the edges of the sharpening of both knives can be turned towards the root system: wood (mon). The force on the verge of sharpening the displaced knife 2 in this case will be less as a result of the propagation of compression deformation along the fibers to a greater length, and the possible propagation of cracks in the mon direction does not damage the stem of the tree.

The implementation of the proposed device will eliminate chipping in tree trunks (logs) resulting from power cutting with knives, and thereby increase the volume of business wood, reduce the cutting effort by 15-20%, which approximately gives an annual economic efficiency in relation to the LP-felled machine. 19 in the amount of 1,500 rubles.

Claims (2)

1. APPARATUS for transverse cutting of wood, including parallel and offset relative to each other in the direction of cutting knives, characterized in that, in order to eliminate chipping of wood and reduce cutting effort, The knife is made with one-sided sharpening, with the edges of the sharpening of the knives facing each other, and the amount of offset of the knives is 0.01-0.35 of the width of the cut, each knife being made with two-sided undercuts relative to the edge of its sharpening. 2. The device according to claim 1, characterized in that the undercut on the knife displaced in the cutting direction, facing the other knife, partially overlaps the edge of sharpening the latter. Sources of information taken into account in the examination 1. USSR author's certificate number 507276, cl. A 01 G 23/08, 1974. 2, USSR Author's Certificate 586874, cl. A 01 G 23/08, 1976.