The invention relates to a blade, in particular for a meat grinder. Meat grinders of this type are used in particular in the meat-processing industry.
During the operation of the meat grinder, the material to be ground is pressed against the cutting set by means of a screw conveyor. The cutting set usually consists of pre-cutters, washers and blades. The cutting elements of the cutting set used must withstand these loads. The blades are mounted on a blade journal and have a central hub provided with a bore for the purpose of preventing rotation of the blades relative to the journal. In order to prevent accumulations around the hub of material to be ground, in a known blade according to document DE 199 08 665 C1, sealing rings were provided at the inner end of the knife blades adjacent to the hub. These sealing rings have the height of the knife blades. Advantageously, a wear equilibrium is established between the wear surface of the knife blades and the sealing ring. Due to wear, the blades must be reground after a certain period of time. However, such a blade according to DE 199 08 665 C1 shows disadvantages during regrinding of the knife blades.
Based on this prior art, an improved blade is to be proposed. This object is achieved with a blade having the features of claim 1. The blade configured in this way facilitates the grinding of the cutting edges and of the sealing ring.
The new blade also has a central hub provided with a bore for a rotation-fixed chamfer on a blade journal and a plurality of knife blades with cutting edges. In this blade, the cutting edges are preferably provided on both sides. The radially outer ends of the knife blades are connected to a blade ring. The radially inner ends of the blade wings terminate in an inner rim. A collar-like sealing ring is provided between the hub and the inner ends of the blade wings. In one embodiment, on the other hand, the same height as the hub has the same height, so that when grinding the blades and the sealing ring, the hub is not an obstacle.
In a further embodiment, the sealing ring has, on the one hand, the height of the cutting edges and the hub has a lower height than the adjacent sealing ring. Also in this case, the hub does not impede the grinding of the blades and the sealing ring. The height of the hub can be so small that it does not protrude beyond the inner rim.
The sealing ring is preferably provided only on one side of the blade, preferably on the outlet side. On the other side, the side without a sealing ring, the hub has a height greater than the height of the blades. In this case, too, the hub impedes the grinding of the blade less, since no sealing ring is provided in the region of the inner rim of the blade and the cutting edges are arranged at a sufficient distance from the hub, for example at a distance of 3 mm to 25 mm.
In addition, for good mixing of the material to be ground, the blade can have knife blades with different cutting edges, namely, on the one hand, cutting edges which extend over the entire radial length of the blade wings, that is to say between the inner ring and the outer blade ring, and on the other hand cut the cutting edges which are shortened in their radial length. The cutting edges are present on both sides of the blade wing, that is, both on the inlet side and on the outlet side. In this case, in particular, an alternating arrangement of full-length and shortened cutting edges on the blade is provided. Such an arrangement is provided in particular for the outlet side but also for the inlet side. In a preferred embodiment, each blade wing has on one side a shortened cutting edge and on the other side a full-length cutting edge. As a result of the cutting edges of different lengths, the material to be ground is mixed in addition to the rotary movement of the blade. For components which accumulate on the outer diameter of the blade, in a preferred embodiment, a plurality of separating openings can be provided on the outer blade ring, which facilitate the further transport of the material to be ground.
The good mixing of the material to be ground is further supported by openings of different sizes, namely openings in each case between two knife blades, the inner ring and the outer blade ring. The openings of different sizes are produced, for example, by blade wings of different widths. However, in the case of equally wide knife blades, it is also possible to achieve intermediate spaces of different sizes if the blade wings protrude from the inner ring at different angles. In both cases, there are openings which have different angles between the adjacent blade wings. Furthermore, it has been shown that such differently sized openings, in particular when there is no symmetrical arrangement of openings in the blade of different sizes, vibrations of the blade are prevented during the rotation of the blade.
In the drawing, an exemplary embodiment of the new blade for a meat grinder is shown. The drawing is in several figures, of which:
The blade 10 has centrally a hub 11 with a through bore 12. This central hub 11 serves to support the blade 10 in a rotationally fixed manner onto a blade journal which is connected to a screw conveyor of the meat grinder. Upon rotation of the screw conveyor, the blade 10 is rotated. In this example, the hub 11 has a coding 13, so that only suitable blades 10 can be placed on a coded blade journal with an identical cross section. This coding also has the advantage that the blade 10 cannot be arranged incorrectly in the meat grinder but always points into the outlet side shown in
For good mixing of the material to be ground and for preventing vibrations of the blade 10 during the operation of the meat grinder, differently sized openings 21 are also provided, which show different angles a1 to a8 between the adjacent knife blades 14. In this example, all blade wings 14 are the same width. The openings 21 of different sizes between in each case two knife blades 14, the inner ring 19 and the outer blade ring 15 are achieved in that the blades 14 protrude from the inner ring 19 at different angles. The openings 21 in the blade 10 are arranged asymmetrically, so the stated angles have the following values: a1=41°, a2=42°, a3=48°, a4=43°, a5=47°, a6=46°, a7=44°, and a8=49°. This asymmetrical arrangement of larger and smaller openings 21 promotes the smooth rotation of the blade 10.
On the outlet side of the blade 10 shown in
No sealing ring is present on the opposite side of the blade, the entry side. Here, adjacent to the hub 11, the inner rim 19, from which the blade wings 14 extend outwardly to the outer blade ring 15, is arranged adjacent to the hub 11. The inlet side of the blade 10 shown in
Knife blades 14 with shortened cutting edges 17 and full-length cutting edges 16 are also provided on this entry side. As can be better seen from
This arrangement leads to a good mixing of the material to be ground. Should components of the material to be ground accumulate at the outer diameter, that is, on the inner side of the outer blade ring, they can be moved further on the outlet side via separating openings 20 in the conveying direction. In this example, there are four separating openings 20, shown in
Number | Date | Country | Kind |
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20 2020 103 763.3 | Jun 2020 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2021/058914 | 4/6/2021 | WO |
Publishing Document | Publishing Date | Country | Kind |
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WO2022/002450 | 1/6/2022 | WO | A |
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4153208 | Vomhof | May 1979 | A |
4422582 | Roeger | Dec 1983 | A |
20130284835 | Quadrana | Oct 2013 | A1 |
Number | Date | Country |
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201002042 | Jan 2008 | CN |
1759328 | Jan 1958 | DE |
1851135 | May 1962 | DE |
2901112 | Jul 1980 | DE |
29905706 | Jul 1999 | DE |
19908665 | Jan 2001 | DE |
102009049844 | Apr 2011 | DE |
102013018785 | May 2015 | DE |
102017109978 | Nov 2018 | DE |
202020103763 | Aug 2020 | DE |
2821143 | Jan 2015 | EP |
Entry |
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International search report in international patent application No. PCT/EP2021/058914, dated Jun. 22, 2021. |
Number | Date | Country | |
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20230191422 A1 | Jun 2023 | US |