FI122766B - Chopper rotor - Google Patents

Description

HAKKURI ROTATOR

The present invention relates to a chopper rotor according to the preamble of claim 1.

Nowadays, wood is chopped using a rotary chopper with rotating blades attached to it. The rotor has a housing which acts as a rotation axis of the rotor 10. The body is so-called. solid steel as disclosed in FI95109. The blades are fixed to the rotor by milled grooves, the blades are parallel to the rotor axis and also along the entire length of the rotor.

A disadvantage of the rotors of a drum chopper of the type described above is that the chips are ejected by the blades. The removal of chips strongly resists rotor rotation and thus increases the need for rotor rotating force, thereby substantially reducing the efficiency of the chopper. The chips cause friction on the rotor and its housing, which increases the temperature of the rotor and the housing. As the temperature increases, the blade sharpening interval increases, and as the blades warm and cool, the blades become softer, which increases the blade costs. The wood to be chipped rubs against the surface of the rotor, also causing an increase in the rotational power of the rotor and an increase in heat on the surface of the rotor, which can cause the chip to ignite. The feed force of the wood to be chipped must also be high, which easily causes so-called feed rolls. digging into the wood to be chipped, whereupon the wood stops and the chopper becomes blocked.

It is an object of the present invention that the chips removed by the chopper blades from the trees pass well through the rotor so that they do not cause friction. A further aim is to extend the sharpening interval of the blades. It is also an object to position the blades on the rotor si-30 so that the rotor does not vibrate when rotating. The cutting angles of the blades also have to remove the rotor axial forces.

The foregoing disadvantages can be overcome and the above-mentioned objects are achieved by a chopper rotor according to the invention, characterized by what is defined in the characterizing part of claim 1. Preferred embodiments of the invention are disclosed in the dependent claims.

The main advantage of the invention is that the chips removed by the chopper blades from the trees have good access to the exhaust passage through the rotor along the chip passage below the blades so that they do not cause friction to the rotor and the rotor housing. Since the chips do not cause friction on the rotor and its housing, the power requirement of the chipper is small in relation to the amount of wood fed to the chipper. The feed-in power requirement of the feedable trees is also small in relation to the number of trees, since the blades are so-called. suck trees into a chopper. The blades and casing will have a low heat so the blades will stay sharp for a long time, resulting in a long blade sharpening interval. The cutting angles of adjacent blades are in opposite directions, whereby the opposing cutting angles of the blades eliminate the rotational axial force, i.e. the so-called. the cutting angles cancel out the force exerted by each other. The blades are located in different sectors viewed from the end of the rotor, whereby the blades balance the rotor, thus preventing the rotor from vibrating during rotation. Rotor vibration and offset force extensions substantially extend the durability of the rotor bearings. It is clear that the invented chopper rotor achieves great economic savings in wood chipping.

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The invention will now be described in detail with reference to the accompanying figures.

Figure 1 is a top plan view of a chopper rotor according to the invention.

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Fig. 2 shows the chopper rotor of Fig. 1, without blades, cut in direction A-A, perpendicular to the end of the body.

Figure 3 illustrates another embodiment of the invention in which the bottom of the rotor chute of the chipper of Figure 1 30 is curved, without blades, cut from A to A, perpendicular to the end of the body.

Fig. 4 shows the chopper rotor of Figs. 1-3 perpendicular to the front 3.

Figure 5 is a central sectional view of the chopper rotor of Figures 1-4, without blades.

Fig. 6 shows the chopper rotor of Figs. 1-5, viewed perpendicular to the end.

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Fig. 7 shows a top view of the rotor mounting body of the chopper according to Figs. 1, 2, 4 and 5, the direction of rotation being counterclockwise.

Fig. 8 shows the mounting frame of Fig. 7, viewed perpendicularly from the side, the circular direction being in a clockwise direction.

Fig. 9 shows the mounting frame of Figs. 7 and 8, viewed from the wood feeding direction, i.e. perpendicular to the front.

Fig. 10 shows the mounting frame of Figs. 7-9, viewed perpendicularly from the side, the direction of rotation being anticlockwise.

In the figures, the parts are designated as follows. Frame 1. Mounting frame 2 having outer edge 2a, side surface 2b, chip groove 2c and strip 2d. Side surface 2b has ul-25 space surface 2ba. A stop 3 having an outer surface 3a. A blade 4 having a body 4a, a cutting surface 4b and a securing member 4c. The cutting surface 4b has a cutting angle 4ba. Chipway 5 with bottom 5a. Attachment part 6 to which the blade 4 is screwed. Direction of rotation 7.

30 The figures show a chopper rotor used to chop wood. The figures do not show the known chipper structure. The chopper rotor is rotatably mounted on its housing to rotate, the rotor being rotated by a combustion or electric motor. The wood is fed in a known manner, for example, by means of wood chipped with feed rollers, which is chipped when it meets the rotor rotating in the housing. The chip 35 exits the housing due to the force exerted by the rotary motion of the rotor.

4

The chopper rotor shown in the figures has one or more chassis 1 to which is attached one or more chassis 2 with one or more blades 4.

5 The frame 1 is fastened to the axis of rotation by means of known friction sleeves or wedges.

It has now been found in the figures that between the blade 4 and the frame 1 there is an open chip passage 5 which extends into the fixing frames 2, the depth of the chip groove 2c in the fixing frames 2. Figure 2 shows that, viewed from the end of the body 1, the cross-sectional area of the cutting passage 10 is 20 to 40% of the diameter of the chopper rotor. The chip passage 5 is 0-20 percent wide in width or in the width of the cutting surface 4b of the blade 4. The chip passage 5 starts from the front of the blade 4 and extends below the blade 4 behind it. According to the best construction shown in Figure 3, the bottom 5a of the chip passage 5 is inclined, whereby it acts as an effective wind blade when the chopper rotor rotates; The strong air blowing of the base 5a also cools the chopper rotor, thereby improving the life of the blades 4. In Fig. 3, the bottom 5a of the chip passage 5 is curved in the direction of rotation 20 forward. The bottom 5a of the chip passage 5 may also be straight as shown in Figures 2, 7, 8 and 10.

Figures 6, 7 and 9 show that the side surface 2b of one or more fastening bodies 2 has one or more chip grooves 2c. The chip groove 2c is at 25, whereby the chip groove 2c widens the chip path 5. The chip groove 2c is milled or otherwise machined to the mounting frame 2, wherein the mounting frame 2 is thinner than the chip groove 2c. The chuck grooves 2c at the ends of the chopper rotor have milled grooves 2c only on the inner side of the chopper rotor 2b of the side surfaces 2b, so that the outer side surfaces of the end chocks 2 are straight. In the figures, the ulu cosmic surfaces 2ba of the fixing bodies 2 at the ends of the chopper rotor have projections 2d which prevent the chips from being packed at the ends of the chopper rotor. The attachment body 2 is a circular plate-like part when viewed from the end of the body 1 with an outer edge.

«5

The figures show that there is a stop 3 between the fastening bodies 2, the outer surface of which is 3 to 25 mm inside the outer edge 2a of the fastening body 2. Specifically, Figure 2 shows that the stop 3 is an annular ring with an opening at the chip passage 5. The diameter greater than the stop 3 of the outer edge 2a of the mounting body 2 reduces the friction between the wood and the chopper rotor, the end of the wood to be chipped collides with the outer edge 2a, the outer edge 2a has a small cross section;

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The small chipped trees stop on the outer surface of the stop 3, whereby the quality of the chips is even, no barking can happen.

Inventively, the cutting angles 4ba of adjacent blades 4 are in different directions, whereby no strain is exerted on the rotor of the 15 chopper, since the opposing cutting angles 4ba cancel each other's axial force. Preferably, the number of blades 4 is even. Inventively, as shown in Figure 5, the blades 4 are viewed from the end of the chopper rotor in different sectors, whereby the blades 4 do not cause vibration when rotating the chopper rotor.

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The invented chopper rotor can be made by known methods and machines of making the chopper, from raw materials known in the hackers.

It will be apparent to one skilled in the art that the invention is not limited to the above alternatives, but that many modifications are possible within the scope of the inventive concept as defined by the appended claims.

Claims (11)

A rotor for a wood chipper used for chipping wood, said wood chipper rotor comprising one or more frames (1), to which one or more fastening frames (2) having one or more knives (4), there is an open clamp (5) between the knife (4) and the frame (1), and the bottom (5a) of the clamp (5) is straight or curved. Rotor for a wood chipper according to claim 1, characterized in that the area of the cross-section of the chuck (5) is 20-40 percent of the area of the chipper rotor diameter. Rotor for a wood chipper according to claim 1, characterized in that the chuck (5) is as wide as its cutting surface (4b) or 0-20 percent wider than the cutting surface (4b) of the knife (4). Rotor for a wood chipper according to claim 1, characterized in that the chuck (5) starts in front of the knife (4) and extends behind it under the knife (4). Rotor for a wood chipper according to claim 1, characterized in that the side surface (2b) of one or more fastening frames (2) has one or more clamping rafters (2c). Rotor for a wood chipper according to claim 5, characterized in that the clamping groove (2c) coincides with the clamping groove (5), whereby the clamping groove (2c) makes the clamping groove (5) wider. Rotor for a wood chipper according to any one of claims 1-6, characterized in that the fixed frame (2) consists of a disc-shaped part with a round outer edge. Rotor for a wood chipper according to claim 1, characterized in that there is a counterpart (3) between the fastening frames (2) whose outside is 3-25 mm inside the outer edge (2a) of the fastening frame (2). Rotor for a wood chipper according to any one of claims 1-8, characterized in that the counterpart (3) is a ring with a round outer edge which has an opening at the chute (5). Rotor for a wood chipper according to claim 1. characterized in that the cutting angles (4ba) of adjacent blades point in different directions, whereby the wood chipper rotor is not subjected to axial pointing. Rotor for a wood chipper according to claim 1, characterized in that the knives (4) seen from the end of the wood chipper rotor are in different sectors, where the knives (4) during their rotation do not cause vibrations of the wood chipper rotor.