Claims
- 1. Process for cutting material on the inner wall of a drum, including the steps of guiding round knives each having a center of rotation on an arc of a circle around the drum axis along the drum inner wall while maintaining and round knives, nonrotating about their respective centers of rotation,
- continuously feeding material into said drum while rotating said drum around said axis with sufficient speed so that the fed material is guided to and positioned against the inside of the drum all by the centrifugal force and cut by said round knives while positioned against the inside of the drum wall,
- and continuously withdrawing the cut material from the drum thus rotating.
- 2. Process according to claim 1 and further including angularly displacing said round knives about their respective axes to expose a different cutting portion of said round knives as said knives move along said arc.
- 3. Process according to claim 1 and further including rotating said round knives and said drum about the drum axis in the same direction.
- 4. Process according to claim 1, and further including rotating said round knives and said drum about the drum axis in opposite directions.
- 5. Apparatus for cutting material on the inner wall of a drum and wherein round knives are guided on an arc of a circle around the drum axis along the drum inner wall while maintaining the round knives nonrotating about their respective centers of rotation comprising,
- said drum having said inner wall,
- said round knives,
- axle means for mounting said round knives stationary about their centers of rotation,
- means for rotatably mounting said round knives held stationary on said axle means angularly spaced around the drum axis guidable along said inner wall,
- means for rotating said drum around said drum axis with sufficient speed to position said material against the inside of said drum wall,
- means for continuously feeding said material into said drum while said drum is rotating with sufficient speed to position said material against the inside of the drum wall,
- means for rotating the assembly of said round knives about the drum axis along the inside of the drum wall to cut said material while said drum is rotating with sufficient speed to position said material against the inside of the drum wall, and means for continuously withdrawing the cut material from said drum while said drum is rotating with sufficient speed to position said material against the inside of the drum wall.
- 6. Apparatus according to claim 5 and further comprising,
- a plurality of said round knives,
- and means for rotatably mounting said round knives angularly spaced around the drum axis guidable along said inner wall.
- 7. Apparatus according to claim 6 and further comprising,
- means for supporting said round knives equiangularly about the drum axis.
- 8. Apparatus according to claim 6 wherein the radial distance between each round knife and said inner wall relative to that of each other knife is within the range of 10 to 20 mm and the angular spacing between adjacent round knives about the drum axis is within the range 30 degrees to 90 degrees.
- 9. Apparatus according to claim 8 wherein said radial distance is substantially 15 mm and said angular separation is substantially 60 degrees.
- 10. Apparatus according to claim 6 wherein at least two of said round knives are angularly spaced about the drum axis by 180 degrees and the radial distance between one of the latter knives and said inner wall and that between the other and said inner wall differs by substantially 15 mm.
- 11. Apparatus according to claim 6 wherein said means for supporting said round knives comprises a tube-shaped cylinder rotatably mounted about the drum axis,
- and means for mounting said round knives on the outer surface of said tube-shaped cylinder.
- 12. Apparatus according to claim 6 and further comprising means for selectively positioning each of said round knives in a predetermined angular orientation about the round knife axis selectively,
- whereby each knife may be selectively angularly displaced to maintain a relatively sharp cutting edge adjacent to said inner wall.
- 13. Apparatus according to claim 12 wherein said means for selectively positioning comprises a plurality of openings angularly displaced about the knife axis and an indexing pin for engagement with a respective one of said openings.
- 14. Apparatus for cutting material on the inner wall of a drum and wherein when operating said apparatus round knives are guided on an arc of a circle around the drum axis along the drum inner wall while maintaining the round knives nonrotating about their respective centers of rotation comprising,
- said drum having said inner wall,
- said round knives,
- axle means for mounting said round knives stationary about their centers of rotation,
- means for rotatably mounting said round knives held stationary on said axle means angularly spaced around the drum axis guidable along said inner wall,
- means for continuously feeding material into said drum when operating while rotating said drum around the drum axis with sufficient speed so that the fed material is guided to and positioned against the inside of the vessel wall by the centrifugal force and cut by the round knives when operating while positioned against the inside of the drum wall,
- means for continuously withdrawing the cut material from the drum when operating and thus rotating,
- and a plurality of removable protective strips mounted for protecting said round knives when being mounted and demounted with said apparatus not operating.
Priority Claims (2)
| Number |
Date |
Country |
Kind |
| 3122266 |
Jun 1981 |
DEX |
|
| 3202618 |
Jan 1982 |
DEX |
|
Parent Case Info
This is a continuation-in-part of application Ser. No. 378,520 filed May 17, 1982, now U.S. Pat. No. 4,520,963, portions of which are reproduced herein as background of the present invention, and a continuation of application Ser. No. 461,254 filed Jan. 26, 1983, now abandoned.
The invention concerns a process as well as an equipment for cutting material on the inner wall of a drum.
Such processes and equipment are used for instance in the meat processing industry. It is of importance to obtain an exact fine cutting for an excellent bond among water, fat and protein by selecting the shape of the knife edges and maintaining their distance from the inner side of the drum wall as low as possible.
This result can be obtained of course by the usual cutter knives of cutters which are used in the meat industry, but they have many great disadvantages.
Due to the fact that the material to be cut is often a relatively thin layer on the inner side of the drum wall, a small sector of the knife edge is utilized only. When this sector of the knife edge is blunt, the knife must be changed and reground. This process takes much time, work and costs, as it can be carried out on special machines only, because of the individual knife shapes.
Another disadvantage is that a relative heavy knife assembly results from the required total number of knives with appropriate rings. Its exact dynamic balancing is difficult, especially after grinding of knives.
Another disadvantage is the long projecting knife shaft of the cutting machine, which is necessary for the knife assembly. When running at high speed, slightest unbalances of the knife assembly cause dynamic vibration of knife shaft and bearing.
Considering this stage of technology, the development must create a process and an equipment of the kind as mentioned above, with removal of the stated disadvantages, especially allowing the whole cutting edge to be full utilizable, simplifying regrinding of the knives and removing or reducing problems of balancing for the fast rotating knives.
This problem is solved according to the invention with round or circular knives guided on an arc of a circle around the drum axis along the drum inner wall. The circular knives are preferably nonrotating about their respective centers and can be angularly displaced around their respective centers after wear and tear of the cutting edge in the cutting sector adjacent the drum wall, so that about six cutting positions result and the whole circumference of each round knife can be used for cutting.
Problems of balancing don't or hardly occur because angularly displacing the round knives around their respective centers to a new unused cutting area does not introduce unbalance.
When the entire circumferential edges of the round knives is completely utilized following angular displacement through a complete revolution, the round knives can be easily replaced. Moreover, the round knives can be easily reground because of the circular form and the small size.
Moreover, the small thickness of the round knives and the flow-favourable shape of the part of round knife dipping in the material to be cut, are of great advantage. The friction produced by the round knives in the material to be cut, which effects the quality of processed material, is very low.
The so-called drawing cut, desired by the meat processing industry, results from the relatively large ratio of the inside diameter of the drum to the diameter of the round knives.
A number of round knives are preferably used, which are guided along the drum inner wall in predetermined axial distance and angular distance, referred to the drum axis. The bearing is exposed to relatively insignificant strains because of the rotationally symmetric arrangement.
The round knives are preferably the same size, which is of special advantage for mounting, knife storage and for the regrinding process.
It has proved to be a special advantage when adjacent round knives are separated by a distance of about 10 to 20 mm, preferably 15 mm, and an angular distance, referred to the drum axis of 30.degree. to 90.degree., preferably 60.degree..
According to a preferred form of the invention, the drum is a rotating hollow cylinder with the material to be cut held on its inner surface by the centrifugal force of the rotating hollow cylinder. The material to be cut of a layer thickness of about 5 to 15 mm is guided in axial direction along the inner wall of the hollow cylinder. A continuous cutting of material results in this way, compared with the usual known cutters, where only a discontinuous cutting of material is possible.
To utilize the whole circumference of the rounded knives as cutting edges, they are preferably mounted rotatably, but in different fixed angular positions. In a specific form the round knives are provided with holes uniformly displaced on a circle concentric with their respective centers for accommodating an indexing pin fixed on the respective knife holder. The holes are preferably numbered consecutively.
Moreover, it has proved to be of practical advantage that at least three removable protective strips be mounted on the tube-shaped cylinder basic body within a circle somewhat larger than the circle inducing the outermost edges of the round knives. These strips prevent round knives from contacting the inside wall of the drum and damaging the cutting edges. Prior to starting the cutting machine, the protective strips are removed. The strips are replaced on removing the knife head from the knife shaft of the cutting machine.
US Referenced Citations (7)
Foreign Referenced Citations (1)
| Number |
Date |
Country |
| 179712 |
May 1922 |
GBX |
Continuations (1)
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Number |
Date |
Country |
| Parent |
461254 |
Jan 1983 |
|
Patent Grant
4623096
