EP0505701A1 - Garden waste shredder with a blade housing containing rotating, powered flat blades - Google Patents

Abstract

Garden waste shredders are provided with a blade housing (1) arranged on a frame (4) which bears the drive motor and a charging funnel and surrounds a lower ejection space and in which there is a blade carrier disc (7) which is to be driven in rotation about an essentially vertical axis and is provided with essentially radially extending passage slots (8) and flat blades (10) arranged above the latter in the manner of cutting knives. Furthermore, a counterbearing insert (13) is provided in the blade housing (1), said insert having, at the bottom, a lower counter-cutter (18) which interacts with the cutters (10') of the flat blades (10) and extends in a flat and essentially radial fashion. In order to be able to use the garden waste shredder to cut up even relatively strong branch material to the largest possible extent without producing much noise, the blade cutters (10') consist of short blade cutter sections (10'', 10''') which extend over a sub-length area, which constitutes less than half the length, of the lower counter-cutter (18) which interacts with them, at least some of these blade cutter sections (10'', 10''') being arranged radially offset with respect to one another. <IMAGE>

Description

The invention relates to a garden shredder with a knife housing arranged on a frame supporting the drive motor and a feed hopper and surrounding a lower ejector chamber, in which there is a knife carrier disk to be driven around a substantially vertical axis, which has essentially radial passage slots and, above it, planer knife-like Arranged flat knives is provided and furthermore, an abutment insert is provided in the knife housing, which has a flat and substantially radially extending lower shear, which cooperates with the cutting edges of the flat knives.

Garden shredders of the above type are known from DE-OS 37 22 339. They are still regularly provided with pre-comminution knives arranged in the center of the knife carrier disc, which interact with an inner counter cutting edge which is present on the abutment insert and runs obliquely upwards. Garden shredders equipped with such a knife mechanism work at a comparatively low speed and also relatively quietly with a comparatively low drive power. The chopping material, in particular branch or knot-shaped garden waste, can be fed in unsorted via the feed hopper, since it is sorted by the knife mechanism and in its interaction with the counter-cutting edges on the abutment insert, so to speak, that the larger or stronger knot material from the Flat knives pressed radially outwards and planed in Disc shape is shredded or machined, while the thinner branch and twig material is pressed inwards by the surrounding flat knives in cooperation with the abutment insert to the pre-shredding knives, where it is shredded or shredded more quickly. In these known garden shredders of the type in question, the flat knives arranged on the knife carrier disc extend with straight cutting edges over the entire length of the lower shear bar interacting with them. This means that the discarded branches are always cut in the full width of the flat knives. However, this still places a comparatively narrow limit on the thickness of the branch material to be shredded, especially since the motor power required for this is still relatively large and the degree of shredding of the chopped material that can be achieved is still not fully satisfied.

The invention is therefore based on the object of improving and perfecting a garden shredder of the type in question in such a way that even stronger branch material can be shredded comparatively quietly and extensively with it without any additional construction and motor effort, so that the garden waste that has been shredded with it, if necessary, can also be shredded can be composted even better than before.

Starting from a garden shredder of the type mentioned at the outset, this object is essentially achieved according to the invention in that the knife edges consist of short knife-cutting sections which extend over a less than half the partial length range of the lower shearbar interacting with them, and at least some of these knife-cutting sections being offset radially are arranged to each other. In this way, it is possible to chop even stronger knot material more efficiently than before with comparatively little drive effort and at low speeds, because the knot material is no longer disc-shaped in its full width, but is only cut or chopped into strips in the short knife-cutting sections of the corresponding section. This can on the one hand even much thicker branch material than effectively shredded and on the other hand the degree of comminution of the chopped material can be increased, and all of this with little drive effort and in a low, low-noise speed range.

It has proven to be particularly advantageous if the flat knives are each provided with a plurality of knife cutting sections located next to one another, but offset in terms of height, which preferably form a continuous, corrugated or angled cutting edge. Flat knives designed in this way thus cut respectively narrow and differently thick or thin chip strips from the respective lower end of the branch material which are then subdivided even more finely as they pass through the passage slots and the ejection area located below the knife carrier disc, so that the chopper as a whole passes through Garden waste leaves it in a comparatively finely divided form and can therefore also be composted particularly well.

In practice, it has proven to be advantageous if four flat knives, each with three knife cutting sections arranged vertically offset from one another, are arranged on the knife carrier disc, two flat knives lying opposite one another with a knife cutting section in the middle and the other two flat knives knife cutting sections at an elevated position at both ends. Such a comparatively simply graduated knife cutting edge design already provides effective comminution of even thicker branch material, the different chip thicknesses being able to be achieved by correspondingly more or less high vertical displacement of the knife cutting sections.

The desired chip thickness of the comminution material can also be influenced by the fact that the knife carrier disc in its sections adjacent to the passage slots and opposite the flat knives provided with staggered knife cutting sections with the chip thickness of the shredding material additionally determining, higher lying embossing areas.

Further features according to the invention are the subject of further dependent claims.

Fig.1

den hier allein interessierenden Teilbereich des Gartenhäckslers in senkrechtem Schnitt,

Fig.2

die gleichfalls zum Teil geschnittene Draufsicht auf den Häcksler der Fig.1,

Fig.3

eine bevorzugte Ausführungsform der Messerträgerscheibe in der Draufsicht,

Fig.4

einen Schnitt nach der Linie IV-IV der Fig.3,

Fig.5

Vorderansichten der in Fig.3 dargestellten Flachmesser mit zugehörigen Schnitten entsprechend den Linien a-a und b-b,

Fig.6

die Draufsicht auf eine andere Ausführungsform der Messerträgerscheibe,

Fig.7

einen Schnitt nach der Linie VII-VII der Fig.6,

Fig.8

eine der Fig.5 entsprechende Darstellung der zur Fig.6 gehörenden Flachmesser,

Fig.9

eine weitere Ausführungsform der Messerträgerscheibe in der Draufsicht,

Fig.10

einen Schnitt nach der Linie X-X der Fig.9,

Fig.11

die Draufsicht auf eine vierte Ausführungsform einer Messerträgerscheibe und

Fig.12

einen Schnitt nach der Linie XII-XII der Fig.11.

The drawing shows a number of exemplary embodiments of garden shredders designed according to the invention and their knife carrier disks with flat knives present thereon. Show:

Fig. 1

the only area of the garden shredder of interest here in a vertical section,

Fig. 2

the likewise partially cut top view of the chopper of Fig.1,

Fig. 3

a preferred embodiment of the knife carrier disc in plan view,

Fig. 4

a section along the line IV-IV of Figure 3,

Fig. 5

Front views of the flat knives shown in FIG. 3 with associated cuts according to lines aa and bb,

Fig. 6

the top view of another embodiment of the knife carrier disc,

Fig. 7

a section along the line VII-VII of Figure 6,

Fig. 8

5 shows a representation of the flat knives belonging to FIG. 6,

Fig. 9

another embodiment of the knife carrier disc in plan view,

Fig. 10

a section along the line XX of Figure 9,

Fig. 11

the top view of a fourth embodiment of a knife carrier disc and

Fig. 12

a section along the line XII-XII of Fig.11.

The garden shredder shown only in detail in FIGS. 1 and 2 is provided with a knife housing 1, which is arranged on a frame 4 carrying the drive motor 2 together with the gear 3, which also partially surrounds the ejector chamber 5. In the knife housing 1 there is the knife carrier disk 7 to be driven in rotation by the motor 2 via the gear 3 and the shaft 6. radially extending through slots 8 and flat knives 10 arranged behind in the circumferential direction 9 is provided. In the central area of the knife carrier disk 7 there are the pre-comminution knives 11 in the form of two upright and upwardly inwardly curved knife bars 11 ', 11'', which are provided with correspondingly obliquely running cutting edges 11''' in the circumferential direction.

Above the knife carrier disk 7 and also its pre-comminution knife 11, an abutment insert 13 with its two-sided fastening feet 13 'is exchangeably fastened in corresponding recesses 12 in the frame 4. This abutment insert 13 consists of one-piece, appropriately shaped iron or steel sheet. This divides the area above the revolving knife carrier disk 7 into a feed area 15 to be fed directly via the feed hopper 14 with the garden waste to be chopped and into the ejector area 16 connected to the ejector space 5. As shown in FIGS. 1 and 2, the abutment insert 13 has a flat web part 13 '' which runs flush with its fastening feet 13 'and which comes close to the orbit of the flat knives 10, and an oblique surface 13''' which is angled in relation thereto and has a gate-shaped recess 17 in its area surrounding the pre-shredding knives 11, one of which Gate flank 17 'forms an inner counter cutting edge which interacts with the cutting edges 11''' of the pre-shredding knife. Between the multiple angled oblique area 13 ^IV and the web part 13 '', the abutment insert 13 has a lower shear bar 18 which runs essentially radially, but runs tangentially to the enveloping circle of the pre-shredding knives 11 in order to interact with the flat knives present on the knife carrier disk 10 to act on the garden waste material to be chopped in the feed space 15, in particular also thicker branch material, with retracting, inwardly directed cutting action.

The consisting of thin-walled sheet or plastic feed or hopper 14 has an obliquely upright outer tube 19, which is fixed with it connected foot flange 20 is easily replaceable on the knife housing 1 or frame housing 4. The vertical partition 21 on the outer tube 19 abuts the upper part of the angled abutment insert 13 and thus ensures that the feed funnel 14 is sealed off from the ejector chamber 5.

The knife carrier disk 7 is provided according to FIG. 3 with four radial passage slots 8 arranged evenly distributed over its circumference and the flat knives 10 located behind it in the circumferential direction 9, which are fastened interchangeably according to FIG. 4 in pronounced recesses 7 'by means of two fastening screws 22 each. For these flat knives 10, it is essential to the invention that their knife edges 10 'each consist of a plurality of short knife cutting sections 10' ', 10' '', which extend over a partial length range of less than half of the lower counter cutting edge 18 interacting with them and at least some of these knife cutting sections 10 '', 10 '' 'are arranged radially offset from one another. If L is the length of the lower shear bar 18 on the abutment insert 13, then the short knife cutting sections 10 ″, 10 ″ ″, measured in the radial direction, should be less than L / 2 wide.

In the case of FIG. 3, each flat knife 10 is provided with three such knife cutting sections 10 ″, 10 ″ ″ located next to one another, but offset in height with respect to one another, but these knife cutting sections of different heights are each radially offset from one another in the direction of rotation of the knife carrier disk 7. According to this, in the present exemplary embodiment, the two flat knives 10a lying opposite one another are each provided with a knife cutting section 10 ″ ″ in the middle and the other two flat knives 10b are provided with knife cutting sections 10 ″ which are raised at their two ends. The knife cutting sections 10 ″, 10 ″ ″ present on each flat knife overall form a continuous cutting edge 10 ′ that runs in a corrugated or cranked manner, as is also shown in particular in FIG. 5. In this way, even thicker branch material fed to the chopper does not differ into slices as before, but only into narrow ones cut thick strips, which only requires a low drive power and low speeds. The low speeds can also further reduce the annoyance caused by such garden shredders. The waste material, in particular also stronger knot material, is cut into strips from the higher-lying knife cutting sections with a high chip thickness D and from the lower-lying knife cutting sections with a smaller chip thickness d, which results in comparatively finely chopped waste material, which subsequently occurs can also compost particularly well.

In the embodiment shown in FIGS. 6 to 8, the knife carrier disk 7 is again provided with four flat knives 10a and 10b, which in the same way as the previously described flat knives each have three knife-cutting sections 10 '', 10 '' 'which are offset next to one another are. The only difference here is that the knife carrier disc 7 in its areas adjacent to the passage slots 8, on the side opposite each of the flat knives 10, is additionally provided with the chip thickness D, d of the comminution material, and at elevated embossed areas 7 '' . As a result, as also shown in FIG. 7, the desired chip thickness can be additionally varied. As shown in FIG. 6 in a schematically simplified illustration, in this way thinner branch material A, which is brought into the inner position shown by the drawing cut as described above, can be cut through the inner knife cutting section 10 ″ with a comparatively large chip thickness D , on the other hand, the thick branch B lying on the embossing area 7 ″ with a smaller chip thickness d is cut into strips.

In the embodiment shown in FIGS. 9 and 10, the individual flat knives 30 are each provided with toothed strip-shaped cutting edges, the teeth 30 'of which and the tooth gaps 30''between them form the cutting knife sections lying next to one another and offset in height from one another. The flat knives 30 have a flat S-shaped overall As shown in FIG. 10 in particular, the profile and can also be provided with toothed strip-shaped cutting edges on both sides and can therefore also be used as a reversible knife. It is understood that particularly narrow chip strips of different thickness can be obtained in these cases.

Another embodiment is illustrated in FIGS. 11 and 12. Here, the narrow knife-edge sections 40 'are provided individually on narrow flat knives 40, each of which is assigned correspondingly narrow, largely also self-contained passage slots 8' in the knife carrier disk 7. The flat knives 40 with their narrow cutting sections 40 'are arranged here on a spiral path 41 surrounding the knife carrier disc center 7' ''. Here, too, the material to be chopped is only cut one after the other in a narrow strip shape, the chip thickness depending on the height of the individual knife cutting sections 40 ′ being different or also constant. In this case as well, as in the cases described above, the drive power and speeds can be kept comparatively low.

Claims (10)

Garden shredder with a knife housing (1) arranged on a frame (4) carrying the drive motor (2) and a feed hopper (14) and surrounding a lower ejector chamber (5), in which a knife carrier disc (7) to be driven around an essentially vertical axis is provided, which is provided with essentially radially extending through slots (8) and flat knives (10) arranged above it in the manner of planer knives, and furthermore an abutment insert (13) is provided in the knife housing (1), which has a bottom with the cutting edges (10 ') the flat knife (10) has a cooperating, flat and essentially radially extending lower shear bar (18), characterized in that the knife edges (10 ') consist of short knife cutting sections (10'',10''') which are over a , less than half the partial length range of the lower shear (18) interacting with them and at least some of them Knife cutting sections (10 '', 10 ''') are arranged radially offset from one another. Garden shredder according to claim 1, characterized in that the flat knives (10) are each provided with a plurality of knife cutting sections (10 '', 10 ''') which are adjacent to one another but offset in terms of height (for example FIGS. 2, 3 and 6). Garden shredder according to claim 2, characterized in that the knife cutting sections (10 '', 10 ''') present on each flat knife (10) form a continuous cutting edge (10') which is curled or angled (Fig. 5, 8) . Garden shredder according to claim 3, characterized in that on the knife carrier disc (7) four flat knives (10a, 10b) arranged uniformly distributed over their circumference, each with three staggered in height Knife cutting sections (10 '', 10 ''') are provided, two opposing flat knives (10a) with a centrally elevated knife cutting section (10''') and the other two flat knives (10b) with knife cutting sections () 10 '') are provided (Fig. 3,6). Garden shredder according to one of claims 1 to 4, characterized in that the knife carrier disc (7) in its flat knives (10a, 10b), which are adjacent to the passage slots (8) and are provided with staggered knife cutting sections (10 '', 10 '''). each opposite section is provided with the chip thickness (D, d) of the crushing material which determines the elevated embossing areas (7 '') (FIG. 6). Garden shredder according to Claim 3, characterized in that the flat knives (30) have a toothed-bar-shaped cutting edge, the teeth (30 ') and tooth gaps (30'') between them form the cutting knife sections which are adjacent to one another and offset in height (Fig. 9, 10) ). Garden shredder according to claim 6, characterized in that the flat knives (30) have a flat S-shaped profile and are designed as reversible knives provided with toothed strip-shaped cutting edges (Fig. 10). Garden shredder according to claim 1, characterized in that the knife cutting sections (40 ') are each provided individually on narrow flat knives (40), at least several of which, together with their associated passage slots (8'), are at a radially different distance from the knife carrier disc center (7 '') ') lie (Fig.11). Garden shredder according to claim 8, characterized in that the narrow flat knives (40) with their narrow knife cutting sections (40 ') and the associated, for the most part lie in self-contained, appropriately narrow passage slots (8 ') on a spiral path (41) surrounding the center of the knife carrier disc (7''') (Fig. 11). Garden shredder according to one of claims 1 to 9, characterized in that the knife carrier disc (7) in its central region located within the flat knives (10 '', 10 ''') provided with the narrow knife-cutting sections (10) with upright pre-shredding knives (11 ) is provided, which cooperate with an upright inner shear bar (17 ') on the abutment insert (13) which is interchangeably mounted in the frame (4) (Fig. 1, 2).

Images