CUTTING UNIT OF A PLANT RAW MATERIAL GRINDER

Abstract

The utility model relates to the field of shredding equipment, in particular to cutting units of rotary shredders of wood and plant materials, and can be used in shredders of branches, twigs, shoots, and other plant waste with rotary cutting elements. The cutting unit comprises a knife (2) with a working edge mounted on a rotor disk (4), and an eccentric (3) mounted so as to be rotatable about an axis and resting against the knife (2). The eccentric (3), when rotating about the mounting axis, rests its working surface against the knife (2), ensuring the limitation of the displacement of the knife (2) relative to the rotor disk (4) under the action of operational loads. In one embodiment, the cutting unit comprises a support in the form of a knife edge (1) secured in an opening in the rotor disk (4), the knife (2) is mounted on the knife edge (1) by means of fasteners passing through the oblong openings of the knife (2), and the eccentric (3) is mounted on the knife edge (1).The oblong holes of the knife (2) provide the ability to adjust the position of the knife (2) relative to the support in the direction of its working edge, including after resharpening. The working edge of the knife (2) protrudes through the hole (6) in the rotor disk (4), secured to the rotor shaft (5). The stop of the eccentric (3) in the knife (2) can be implemented in a recess made in the knife (2), in the edge of the knife (2) opposite to its working edge, in the edge of the oblong hole of the knife (2), in a projection on the knife (2) or in another way that ensures limiting the displacement of the knife (2). 3 ill.

Description

[0001] FIELD OF TECHNOLOGY

[0002] The utility model relates to the field of shredding equipment, in particular to cutting units of rotary shredders of wood and plant materials, and can be used in shredders of branches, twigs, shoots and other plant waste, equipped with rotary cutting elements with knives installed on them, subject to periodic sharpening and adjustment during operation.

[0003] STATE OF THE ART

[0004] Cutting units for rotary crushers of plant materials are known, comprising a rotor disk and knives fixed to it, having a working edge protruding through openings in the rotor disk into the cutting zone.

[0005] A branch shredder chipping unit, according to patent RU 234605 U1 (IPC B02C 18 / 06), features removable and sharpenable knives mounted on a rotor disk. This design allows for resharpening of the knives and adjustment of the resulting chip size by adjusting their position. However, a significant drawback of this solution is the lack of a reliable means to prevent the knife from shifting in the direction of its longitudinal axis under impact loads that occur during operation (a branch striking the cutting edge of the knife, the ingress of solid inclusions, etc.). As a result, the knife shifts relative to its support during operation, disrupting the specified position of its cutting edge relative to the rotor disk plane. This leads to deterioration in cutting quality, increased wear on the unit components, and the need for frequent shutdowns for readjustment of the knife position.

[0006] A known rotary crusher knife, according to patent RU 2235598 C2 (IPC B02C 18 / 18), comprises a knife base, a replaceable cutting tip, and a removable locking element mounted on the base that prevents rotation and axial displacement of the replaceable cutting tips. A disadvantage of this solution is the complexity of the design, due to the multiple components of the replaceable cutting tip, as well as the inability to adjust the protrusion of the working edge relative to the supporting surface after resharpening.

[0007] A brush cutter rotor, patented by RU 2049382 C1, comprises a shaft with disks, support axles, and pivotally mounted chopping knives with an oblong elliptical opening. This design allows for the knife's cutting edges to be adjusted without removing it from the axle. However, the pivoted mounting of the knife on the axle does not ensure rigid fixation of the knife in a given position, making this solution unsuitable for rotary shredders with rigidly mounted knives and precluding fine adjustment of the knife's working edge after resharpening.

[0008] Common disadvantages of known solutions are:

[0009] the absence of a reliable means to prevent the knife from shifting relative to the support in the direction of its mounting holes under impact operating loads;

[0010] difficulty or impossibility of accurately adjusting the amount of protrusion of the working edge of the knife relative to the plane of the rotor disk after each resharpening;

[0011] reduction of the knife service life due to the need to replace it when the original dimensions are lost or when it is impossible to reinstall it in the required position;

[0012] increased costs for consumable cutting elements.

[0013] The stated technical solution is aimed at eliminating the indicated shortcomings.

[0014] DISCLOSURE OF THE ESSENCE OF THE UTILITY MODEL

[0015] The technical problem that the claimed utility model is aimed at solving is the creation of a cutting unit for a plant material shredder that ensures the possibility of multiple resharpening of the knife with its subsequent installation on the rotor with adjustment of the position of the working edge, as well as reliable fixation of the knife from displacement relative to the rotor disk under the action of impact loads that arise during operation.

[0016] The technical result that the claimed technical solution is aimed at achieving is:

[0017] increasing the service life of the knife due to the possibility of its repeated sharpening and re-installation on the rotor with adjustment of the position of the working edge;

[0018] preventing the knife from shifting relative to the rotor disk in the direction of its mounting holes when subjected to impact loads during operation, which ensures that the specified cutting geometry is maintained throughout the entire service life of the knife;

[0019] increasing the operational reliability of the cutting unit by stably holding the knife in a given position;

[0020] reducing the consumption of cutting elements and the cost of their replacement by extending the service life of each knife.

[0021] The specified technical result is ensured by a cutting unit of a plant material shredder, containing a knife with a working edge, mounted on a rotor disk, characterized in that the cutting unit is equipped with an eccentric, mounted with the possibility of rotation around an axis and abutting against the knife, ensuring the limitation of the displacement of the knife relative to the rotor disk under the action of operational loads.

[0022] BRIEF DESCRIPTION OF DRAWINGS

[0023] Fig. 1 - Cutting unit on the rotor of the plant material shredder, front view.

[0024] Fig. 2 - Section A-A of the cutting unit, side view.

[0025] Fig. 3 - General view of the cutting unit on the plant material shredder without the casing.

[0026] The following positions are indicated in Fig. 1-3:

[0027] 1 - knife edge (support);

[0028] 2 - knife;

[0029] 3 - eccentric;

[0030] 4 - rotor disk;

[0031] 5 - rotor shaft;

[0032] 6 - hole.

[0033] IMPLEMENTATION OF A UTILITY MODEL

[0034] The following describes in detail all the components of the present utility model with reference to the drawings and the reference numbers indicated therein for a more complete understanding of the scope and all technical aspects of the claimed technical solution by a person skilled in the art.

[0035] The cutting unit contains (Fig. 1-3):

[0036] knife edge 1, which serves as a support and fastening for the knife;

[0037] knife 2 with a working edge and oblong holes for fastening;

[0038] eccentric 3, which functions as a knife position lock;

[0039] rotor disk 4, on which the knife edge 1 is installed;

[0040] rotor shaft 5, to which rotor disk 4 is rigidly connected;

[0041] hole 6 in rotor disk 4 for protruding the working edge of knife 2 into the cutting zone.

[0042] The edge of the knife 1 is a plate fixed on the disk of the rotor 4 at an angle to its plane and is a support and a base for fastening the knife 2. The edge of the knife 1 is connected to the disk of the rotor 4 by fastening it in an opening made in the disk of the rotor 4, while the shape of the said opening can be rectangular or other, ensuring a reliable mutual arrangement of the edge of the knife 1 and the disk of the rotor 4. The connection of the edge of the knife 1 with the disk of the rotor 4 is made by a welded or other rigid connection, ensuring the immobility of the edge of the knife 1 relative to the disk of the rotor 4 during the operation of the unit.

[0043] Knife 2 is a plate with a sharpened working edge formed on one of its sides and is mounted on the edge of knife 1 with the possibility of removal for subsequent sharpening and reinstallation. At least two oblong holes are formed in knife 2 for fastening it to the edge of knife 1 by means of bolts or other fasteners. The oblong shape of these holes allows for the possibility of changing the position of knife 2 relative to the edge of knife 1 in the direction of its working edge within the length of these holes, which is necessary to compensate for the decrease in the width of knife 2 after its resharpening and to adjust the amount of protrusion of the working edge of knife 2 through hole 6 of rotor disk 4.

[0044] In the central part of the knife 2, a recess is made, designed to interact with the eccentric 3. The recess can have a round, oval or other shape, ensuring the possibility of interaction with the working surface of the eccentric 3.

[0045] Eccentric 3 is mounted on the edge of knife 1 and can be rotated around its mounting axis and is designed to prevent knife 2 from shifting relative to the edge of knife 1 in the direction of its longitudinal axis during operation of the cutting unit. Eccentric 3 is secured to the edge of knife 1 by means of a bolt or other fastening element, which ensures the ability to fix eccentric 3 in a given angular position. The working surface of eccentric 3 is located in the recess of knife 2 and presses knife 2 against the supporting surface of the edge of knife 1, ensuring that knife 2 is held from longitudinal displacement. Since the distance from the mounting axis of eccentric 3 to its working surface changes depending on its angular position, rotation of eccentric 3 provides smooth adjustment of the position of knife 2 relative to the edge of knife 1 and subsequent rigid stop for holding knife 2 in a given position.

[0046] The working edge of knife 2 is positioned so that it protrudes through opening 6 of rotor disk 4 by the amount necessary to effectively cut the feed material. The amount of protrusion is adjusted by positioning knife 2 on the edge of knife 1 by moving it within the oblong openings and securing it in the selected position with fasteners and eccentric 3.

[0047] The cutting unit can be installed on the rotor disk 4 in the amount of two or more units, while the cutting units can be located on the rotor disk 4 evenly around the circumference or symmetrically relative to the axis of rotation, ensuring balancing of the rotor and uniform load on the drive.

[0048] Rotor disk 4 is rigidly connected to rotor shaft 5, which is installed in the bearing supports of the shredder body and is driven into rotation by the engine via a belt, chain or other transmission.

[0049] Working principle.

[0050] The cutting unit operates as follows.

[0051] Preparing for work and installing the knife.

[0052] Before putting into operation and after each resharpening of knife 2, it is installed on the edge of knife 1. Knife 2 is placed on the supporting surface of the edge of knife 1 so that its working edge protrudes through opening 6 of rotor disk 4 by a specified amount. The position of knife 2 relative to the edge of knife 1 is adjusted by moving knife 2 within its oblong openings. After installing knife 2 in the required position, it is preliminarily fixed by tightening fasteners passing through the specified oblong openings. Next, eccentric 3 is adjusted: eccentric 3 is rotated around its fastening axis until its working surface rests against the wall of the recess of knife 2, after which it is fixed in this position by tightening the corresponding fastener. As a result, knife 2 is simultaneously pressed against the supporting surface of the edge of knife 1 by fasteners and held from longitudinal displacement by eccentric 3.

[0053] Starting and idling.

[0054] When the engine starts, torque is transmitted through the drive to rotor shaft 5, and rotor disk 4, together with the cutting units mounted on it, begins to rotate. When no material is fed into the cutting zone, knife 2, mounted on the edge of knife 1 and secured by fasteners and eccentric 3, maintains a constant position relative to rotor disk 4.

[0055] Working mode.

[0056] When the material to be shredded (branches, twigs, shoots, etc.) is fed into the cutting zone, the working edge of knife 2, protruding through opening 6 of rotor disk 4, cuts a layer of the material with each rotor revolution. The cut material is removed from the cutting zone in the form of chips through the discharge opening of the shredder housing. During operation, knife 2 is subjected to significant impact loads directed along its longitudinal axis and tending to shift knife 2 relative to the edge of knife 1 in the direction of the oblong openings. However, the displacement of knife 2 is prevented by eccentric 3, the working surface of which rests against the wall of the recess of knife 2, holding it in its original position. Thus, knife 2 maintains a predetermined amount of protrusion of the working edge through opening 6 of rotor disk 4 throughout its entire service life until the next resharpening.

[0057] Sharpening and reinstalling the knife.

[0058] As the working edge of knife 2 wears, it must be removed from the edge of knife 1 for sharpening. To do this, loosen the fastening element of eccentric 3 and rotate eccentric 3 to a position in which its working surface protrudes from the recess of knife 2. Then loosen the fasteners securing knife 2 to the edge of knife 1 and remove knife 2. After sharpening the working edge, the width of knife 2 is reduced by the amount of metal removed. Sharpened knife 2 is returned to the edge of knife 1 and, by moving it within the oblong holes, the position is adjusted so that the working edge again protrudes through hole 6 of rotor disk 4 by the required amount. Then, the fastening elements of knife 2 are tightened, after which the position of eccentric 3 is adjusted by turning it around the fastening axis until its working surface rests against the wall of the recess of knife 2 and eccentric 3 is fixed by tightening the fastening element.Repeated re-sharpening of knife 2 and its re-installation ensures a significant increase in the service life of each knife.

[0059] Stop.

[0060] When the engine is turned off, the torque on rotor shaft 5 ceases, and rotor disk 4, together with the cutting units, slows to a complete stop. Knife 2, held by fasteners and eccentric 3, maintains its position relative to knife edge 1.

[0061] Emergency situations.

[0062] When a hard inclusion (stone, metal object, etc.) enters the cutting zone or when another impact load acts on the working edge of knife 2, the longitudinal component of the impact load is absorbed by eccentric 3, which rests against the wall of the recess of knife 2, which prevents displacement of knife 2 relative to the edge of knife 1. The lateral (normal to the plane of the knife) component of the load is absorbed by the fastening elements of knife 2 and the supporting surface of the edge of knife 1. Thus, the cutting unit maintains its functionality under the action of impact loads.

[0063] The knife support is not limited to being a rib of knife 1 in the form of a plate welded at an angle to rotor disk 4, but may also be implemented as a bracket, post, block, eye, collar, or other element that secures knife 2 relative to rotor disk 4 in a given position. The support can be attached to rotor disk 4 by welding, bolting, keying, wedge-shaped, or other connection that ensures the immobility of the support relative to rotor disk 4.

[0064] The hole in the rotor disk 4 for fastening the edge of the knife 1 is not limited to a rectangular shape and can have a square, oval, round, trapezoidal or other shape that ensures the installation and fixation of the edge of the knife 1.

[0065] The recess in knife 2 for engaging eccentric 3 is not limited to the central portion of the knife and may be located anywhere on knife 2 that allows engagement with eccentric 3, including closer to one of the side edges of knife 2 or at its end. The shape of the recess is not limited to the described embodiment and may be round, oval, rectangular, polygonal, or other, ensuring contact with the working surface of eccentric 3.

[0066] Eccentric 3 is not limited to being made with a round working surface eccentrically located relative to the fastening axis, and can be made in the form of a cam, a rotary bar with an eccentric working surface, an adjusting wedge or another element that ensures the pressing of knife 2 and prevents its displacement relative to the support.

[0067] The interaction of the eccentric 3 with the knife 2 is not limited to the placement of the working surface of the eccentric 3 in the recess of the knife 2 and can be implemented in other ways that ensure the retention of the knife 2 from displacement relative to the support in the direction of its oblong openings. In particular, the eccentric 3 can be positioned so that its working surface rests against the edge of the knife 2 opposite its working edge (stop against the non-working edge or end of the knife). In this case, the recess in the knife 2 is not performed, and the function of the stop surface is performed by the edge of the knife 2 itself. Alternatively, the eccentric 3 can be positioned so that its working surface rests against the edge of one of the oblong openings of the knife 2, in which case the oblong opening of the knife 2 simultaneously functions as a fastening and stop element. Also, the knife 2 can be provided with a protrusion (lug, boss), and the eccentric 3 is positioned with the possibility of resting against the said protrusion.A mirror-image design is also possible, in which eccentric 3 is mounted directly to knife 2 with the ability to rotate, and its working surface interacts with the corresponding stop surface of the support (the ribs of knife 1), preventing knife 2 from shifting relative to the support. In all of these embodiments, the functional purpose of eccentric 3 is retained—to prevent knife 2 from shifting relative to the support in the direction of the oblong openings of knife 2.

[0068] The fastening elements of the knife 2 are not limited to bolts and can be made in the form of screws, studs with nuts, rivets (provided that they can be removed), pins with a lock or other fastening elements that ensure a rigid fastening of the knife 2 to the support with the possibility of removal.

[0069] The oblong holes of the knife 2 may have the form of rectangular grooves, oval grooves, elongated holes with rounded ends, or another shape that allows the knife 2 to move relative to the support in a given direction.

[0070] Knife edge 1, knife 2, and eccentric 3 can be made of structural steel, tool steel, alloy steel, or other materials that provide the required strength, wear resistance, and sharpening ability. The working edge of knife 2 can be subjected to additional heat or chemical-thermal treatment (hardening, carburizing, nitriding, surfacing with wear-resistant alloys, etc.) to increase wear resistance.

[0071] The number of cutting units installed on the rotor disk 4 can be from two to eight or more, depending on the diameter of the rotor disk 4, the required performance of the shredder and the characteristics of the material being crushed.

[0072] Thus, the declared cutting unit provides:

[0073] the possibility of multiple resharpening and reuse of the knife, which significantly increases its service life;

[0074] reliable retention of the knife from longitudinal displacement under the action of impact operational loads due to the interaction of the eccentric with the recess of the knife;

[0075] the ability to precisely adjust the position of the working edge of the knife relative to the rotor disk after each sharpening;

[0076] simplifies maintenance of the cutting unit due to the ease of removal, resharpening and reinstallation of the knife;

[0077] increasing the operational reliability of the cutting unit and the stability of cutting parameters throughout the entire service life of the knife;

[0078] Reduces operating costs by reducing the need to replace cutting elements.

Claims

1. A cutting unit for a plant material shredder, comprising a knife with a working edge, mounted on a rotor disk, characterized in that the cutting unit is equipped with an eccentric, mounted with the ability to rotate around an axis and rest against the knife, ensuring that the displacement of the knife relative to the rotor disk is limited under the action of operational loads.

2. The cutting unit according to paragraph 1, characterized in that it contains a knife support secured to the rotor disk, wherein the knife is mounted on said support.

3. The cutting unit according to item 2, characterized in that the eccentric is installed on the knife support.

4. The cutting unit according to paragraph 2, characterized in that the knife support is made in the form of a knife edge, which is a plate fixed on the rotor disk at an angle to its plane.

5. The cutting unit according to item 4, characterized in that the edge of the knife is secured in an opening made in the rotor disk.

6. The cutting unit according to paragraph 1, characterized in that the knife is provided with oblong holes for fastening, providing the ability to change the position of the knife in the direction of its working edge.

7. A cutting unit according to claim 1, characterized in that the knife is provided with a recess made on the side of the knife facing the eccentric, wherein the eccentric is positioned with the possibility of resting against the wall of said recess.

8. The cutting unit according to item 7, characterized in that the recess is made in the central part of the knife.

9. The cutting unit according to item 1, characterized in that the eccentric is positioned so as to be able to rest against the edge of the knife opposite its working edge.

10. The cutting unit according to item 6, characterized in that the eccentric is positioned so as to be able to rest against the edge of the oblong hole of the knife.

11. The cutting unit according to paragraph 1, characterized in that the knife is provided with a protrusion, and the eccentric is positioned with the possibility of resting against said protrusion.

12. The cutting unit according to paragraph 1, characterized in that the knife is installed with the possibility of removal for sharpening and reinstallation with adjustment of the position of its working edge relative to the rotor disk.

13. The cutting unit according to paragraph 1, characterized in that the working edge of the knife is positioned so as to protrude through an opening made in the rotor disk.

14. The cutting unit according to item 6, characterized in that the knife is secured by means of bolts passing through the oblong holes of the knife.

15. The cutting unit according to paragraph 1, characterized in that the eccentric is secured by means of a bolt with the possibility of rotation around its axis and fixation in a given angular position.

16. The cutting unit according to paragraph 1, characterized in that at least two cutting units are installed on the rotor disk, located symmetrically relative to the axis of rotation of the rotor.

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