FOOD GRINDING DEVICE

Description

[0001] The invention relates to a food chopping device having the features set out in the preamble of claim 1.

[0002] In the past, so-called grinders were often used to chop foodstuffs such as meat, fish, cheese or fat. These grinders used a rotating blade to chop up the entire amount of food.

[0003] Corresponding meat grinders are described in DE 43 41 606 A1, EP 0 573 759 A1 and DE 195 01 966 A1. Each of these grinders has a feed hopper for the food to be ground and a conveyor screw that draws the food to be ground from the feed hopper and transfers it to a main screw. The main screw feeds the food to be ground to a set of knives comprising several blades. The main disadvantage of these grinders is that unwanted residues such as bone fragments, tendons and sometimes even ground foreign matter end up in the ready-to-sell product. Another disadvantage has been found to be the considerable agitation of the food to be ground in the transition area between the conveyor screw and the main screw, which reduces the fill level of the ground-up module and the overall performance of the ground-up device.Furthermore, cleaning the transition between the transport and main auger in a barely accessible area is particularly cumbersome, which in turn leads to long cleaning breaks and a further reduction in the overall cutting performance.

[0004] For some time now, efforts have been made to combine shredding with the separation of undesirable residues from usable food. US Patent No. 32,060 describes a shredding device for producing a boneless meat product. The known device has a pressure housing with a cylindrical drum wall in which a conveyor screw is rotatably mounted. The conveyor screw consists of a transport screw and a main screw connected to it in a rotationally fixed manner, which differ in terms of their diameter, pitch and shape of the respective screw flight. Usable meat is separated from the bones by means of the main screw and cutting openings arranged in the cylindrical drum wall and is pushed through the cutting openings. Unusable bones are conveyed towards an ejection opening arranged at the end and removed from the pressure housing.However, it has been found to be disadvantageous that the speed and torque of the transport screw and main screw can only be adjusted uniformly and therefore the cutting performance of the main screw in particular is limited.

[0005] EP 2 783 572 B1 discloses a shredding device with a conveyor screw and a main screw, each arranged offset from one another in separate housings. The food to be shredded passes from the conveyor screw housing via an S-shaped connecting pipe into the main screw housing, which is provided with cutting openings and in which the shredding of the food takes place. The conveyor screw and the main screw each have their own motor. In operation, however, it has proven disadvantageous that the food must be pushed by the conveyor screw over a relatively long path through the S-shaped connecting pipe, which results in considerable friction losses and circulation resistance that must be overcome, which negatively impact the cutting performance and service life of the shredding device.

[0006] CN 204362836 U discloses a comminution device with a feed hopper, through the lower section of which extend a conveyor screw shaft and a main screw shaft aligned coaxially therewith. The main screw shaft continues in the axial direction of the conveyor screw shaft into a comminution module. The conveyor screw shaft and the main screw shaft are mounted on a first side in the area of ​​the feed hopper and on an opposite, second side at the end of the comminution module. Both bearing points are therefore spaced very far apart in the axial direction, which in practice results in the disadvantage that, when a large feed quantity of the food to be comminuted is added, the conveyor screw shaft and the main screw shaft begin to vibrate, and the comminution device can only be operated at a reduced cutting power.Furthermore, the known shredding device only achieves a relatively short service life due to the high vibration load.

[0007] The invention was therefore based on the object of developing a shredding device that enables an even higher cutting performance of the food to be shredded.

[0008] The problem is solved by the features of claim 1. The conveyor screw and the main screw are typically aligned axially. The conveyor screw serves to convey the food to be shredded to the main screw and does not perform any shredding work. Since no shredding work needs to be performed by the conveyor screw and a relatively low pressure is exerted on the food to be shredded, only a relatively low torque needs to be provided. The outer diameter of the conveyor screw is usually selected to be larger than the outer diameter of the main screw. Its main screw flight can preferably be formed in a section within the cutting drum on the main screw shaft and transports the food to be shredded at high pressure over and into the cutting openings formed radially in the cutting drum.

[0009] The conveyor screw motor unit and the main screw motor unit are preferably separately controllable and each designed for the expected power requirements. With the help of the main screw motor unit, the main screw can be operated at a different speed than the conveyor screw and with a torque designed for this purpose. A further advantage of the invention is that, thanks to the conveyor screw motor unit and the separate main screw unit, a higher overall drive power can be installed with little effort and the overall food throughput can be significantly increased.

[0010] The main screw shaft is arranged coaxially with the conveyor screw shaft and enclosed by it. Due to this design, a section of the main screw shaft runs centrally within the conveyor screw shaft outside the shredding module. The term "enclosed" refers to the axial enveloping or overlapping of the main screw shaft by the conveyor screw shaft, whereby, within the feed hopper up to the attached shredding module, no entry of the food to be shredded in a radial direction through the conveyor screw shaft to the main screw shaft is possible. This causes the food to be shredded to rotate while being advanced exclusively by the conveyor screw.The main auger shaft transfers no work to the food to be shredded in the feed hopper area, allowing the food to enter the shredding module with reduced flexing work, enabling a particularly high cutting performance of the shredding device. Because the transport auger shaft axially surrounds the main auger shaft, the conveyor auger shaft is evacuated of the food to be shredded, eliminating the need to clean the particularly hard-to-reach area at the feed hopper outlet.

[0011] Furthermore, it is possible to arrange the conveyor screw and the main screw axially one behind the other and in one plane, so that the food to be shredded is fed straight to the cutting drum without any deflections, thus minimizing friction losses of the food to be shredded. This, in turn, ensures a high throughput of the food to be shredded, as the torque generated by the conveyor screw and the main screw is available to maximize cutting performance.

[0012] The conveyor screw and the main screw shaft run at least partially through the feed hopper. A feed hopper is a trough-like container with an upper opening through which the food to be shredded is fed to the shredding device. The conveyor screw runs through the lower end of the feed hopper and draws the food to be shredded from the feed hopper. Within the section of the conveyor shaft running through the feed hopper, the main screw shaft is accommodated by the conveyor screw shaft and evacuated by the feed hopper. This also has the advantage that the food to be shredded is not contaminated by lubricant residues from the main screw shaft or by abrasion during operation of the shredding device.

[0013] A particularly preferred embodiment is one in which only the main screw shaft of the main screw is enclosed by the conveyor screw shaft. Accordingly, no sections of the main screw flight are present within the area of ​​the main screw shaft covered by the conveyor screw shaft. The outer diameter of the main screw shaft is matched to the inner diameter of the conveyor screw shaft in such a way that no contact occurs under the expected operational loads and an annular space formed between the conveyor screw shaft and the main screw shaft is minimized. This results in the advantage that a particularly large free cross-section for the food to be shredded between the conveyor screw shaft and a passage opening to the shredding module is possible, thereby enabling an even higher cutting performance of the shredding device.

[0014] For practical purposes, the conveyor screw shaft is designed as a closed tubular body along its entire axial length. This does not need to be a single, integral unit, but covers the main screw shaft without providing a passage opening for the food to be ground.

[0015] It has proven particularly advantageous if the conveyor screw motor unit and the main screw motor unit are arranged on a side of the conveyor screw facing away from the shredding module. This creates a modular separation of the food shredding and drive technology functional areas. The conveyor screw motor unit and main screw motor unit can be arranged adjacent to each other, making them particularly easy to access for maintenance purposes. Furthermore, the routing of electrical cables can be reduced to a spatially defined area, which is located at a distance from the food to be shredded and is subject to significantly reduced splash water during cleaning.In addition, the installation space around the shredding module remains largely free, so that both the usable food and the non-usable residues can be transported away by means of downstream conveyors that can be arranged in a largely arbitrary manner.

[0016] The feed hopper has a first and second passage opening on opposite sides, through which the conveyor screw shaft and the main screw shaft pass. The first passage opening can be arranged on a side of the feed hopper adjacent to the conveyor screw motor unit and the main screw motor unit and can serve exclusively for the passage of the conveyor screw shaft and the main screw shaft mounted therein. The second passage opening is then arranged on a side of the feed hopper adjacent to the shredding module. The conveyor screw shaft, with its conveyor screw flight, usually extends into the second passage opening. Furthermore, the second passage opening forms a channel for the food to be shredded from the feed hopper to the shredding module.

[0017] Preferably, the shredding module is attached to the front side around the second passage opening. The food to be shredded passes directly from the second passage opening into the shredding module, which is aligned in an extension of the second passage opening, whereby the food to be shredded enters the shredding module in a straight line and without deflection.

[0018] The conveyor screw shaft and the main screw shaft are advantageously mounted in a common bearing block. This minimizes the installation space in the axial extension of the conveyor screw shaft and main screw shaft. The common bearing block can be arranged stationary relative to the feed hopper and spatially between it and the associated conveyor screw motor unit and the main screw motor unit.

[0019] It is sensible to provide a rotatable support for the conveyor screw shaft in the axial extension of the bearing block by means of several first conveyor screw bearings relative to the bearing block, and the main screw shaft by means of at least one first main screw bearing relative to the conveyor screw shaft. The conveyor screw bearing and the main screw bearing are thus arranged within the bearing block and transfer the operating loads occurring both radially and axially to the bearing block. This has the advantage that no significant axial forces need to be absorbed on the shredding module side, allowing the use of small, simple bearings. This allows for particularly rapid installation and removal of the shredding module, particularly for repair and cleaning purposes.

[0020] Preferably, the first conveyor screw bearings and the at least one first main screw bearing are designed as rolling bearings. Rolling bearings are characterized by low bearing friction and a long service life. A potentially complex disassembly of the first conveyor screw bearing and the first main screw bearing only needs to be performed in the event of repairs, since the section of the conveyor screw shaft and main screw shaft adjacent to the first conveyor screw bearing and the first main screw bearing does not need to be removed for cleaning purposes.

[0021] The conveyor screw shaft can have a conveyor screw separation point on the bearing block, and the main screw shaft can have a main screw separation point. At this point, the corresponding shafts can be separated in front of the bearing block and pulled axially out of the feed hopper toward the second through-hole.

[0022] Advantageously, the bearing block is arranged on an outer side of the feed hopper around the first passage opening. The bearing block is thus mounted outside the feed hopper and does not come into contact with the food to be shredded. This installation position of the bearing block is particularly advantageous when the first conveyor screw bearing and the first main screw bearing are designed as roller bearings, since otherwise, additional sealing of the bearing block against incoming food and / or the escape of lubricant would be required.

[0023] A centering insert is inserted into the second passage opening, in which the conveyor screw shaft is rotatably supported by a second conveyor screw bearing, and the main screw shaft is rotatably supported by a second main screw bearing. The centering insert accommodates the second conveyor screw bearing and the second main screw bearing in its central area. Open openings are formed in the centering insert in a decentralized, axial direction, through which the food to be shredded exits the second passage opening and enters the shredding module attached to it.

[0024] Conveniently, the second conveyor screw bearing and the second main screw bearing are designed as plain bearings. The plain bearing can be designed without lubrication, is largely resistant to food penetration during operation, thus eliminating the need for a separate seal, and can be easily removed or disassembled for cleaning purposes.

[0025] The shredding module preferably comprises a pre-shredding drum, which is arranged axially between the cutting drum and the second passage opening. The pre-shredding drum serves to roughly tear the food and prepare it for subsequent shredding and separation. For this purpose, the pre-shredding drum has a closed peripheral wall through which no food to be shredded passes.

[0026] The inner surface of the pre-shredding drum can be configured with slots and grooves, which facilitate coarse shredding. The grooves are shaped like a helical groove and extend through the slots toward the cutting drum. The food to be shredded is pressed into the slots by the rotating main screw, is fixed in the slots, and is then sheared off by the main screw flight of the rotating main screw shaft, which sweeps over the slots.

[0027] For a better understanding, the invention is explained in more detail below with reference to four figures. Fig. 1: a perspective view from behind of a shredding device cut lengthwise; Fig. 2: a perspective side view from the front of the shredding device according to Fig. 1 ; Fig. 3:an enlarged section of a longitudinal section through the shredding device in the area of ​​a bearing block and Fig. 4: an enlarged section of a longitudinal section through the shredding device in the area of ​​a shredding module.

[0028] The Fig. 1 shows a perspective view of a longitudinal section through the shredding device according to the invention, which has a machine frame 70 that is fixedly positioned on the floor by means of several support feet 71 attached thereto. The machine frame 70 supports an upwardly open feed hopper 50, into which the food to be shredded is placed and homogenized and loosened by a mixing shaft 54 ​​running through the feed hopper.

[0029] At a lower end of the feed hopper 50 there is a conveyor screw 10, with which the food to be shredded is fed to a shredding module 20. The shredding module 20 is arranged downstream of the conveyor screw 10 in the axial direction x. The conveyor screw 10 comprises a conveyor screw shaft 12 and a conveyor screw thread 13, wherein the conveyor screw shaft 12 is guided through a first passage opening 51 formed in the feed hopper 50 and is coupled to a conveyor screw motor unit 11, which is particularly well suited to Fig. 2 can be seen. The food to be shredded enters the shredding module 20 through a second passage opening 52, which is arranged on the opposite side of the feed hopper 50 with respect to the first passage opening 51. A centering insert 63 is inserted into the second passage opening 52.

[0030] The shredding module 20 has a cylindrical cutting drum 30 at its end with a plurality of radially aligned cutting openings 31. In the axial direction x, the shredding module 20 is penetrated by a main screw 32, the main screw flight 34 of which rotates over the cutting openings 31. As the main screw 32 rotates, the main screw flight 34 pushes the food to be shredded toward a discharge opening 37, through which the residual materials contained in the food exit the shredding module 20 and are removed by means of a residual material chute 38.

[0031] The food to be processed is relatively softer and is pressed into the cutting openings 31 due to the pressure generated by the main screw 32, held therein, and sheared off due to the rotational movement of the main screw flight 34. Food is discharged 39 through the cutting openings 31.

[0032] The main screw 32 performs the comminution work and, for this purpose, has a separate main screw motor unit 35, which is kinematically coupled to a main screw shaft 33. The main screw shaft 33 extends axially through the comminution module 20 and is formed exclusively in this section with the main screw flight 34. In the second passage opening 52, the main screw shaft 33 enters coaxially into the interior of the hollow conveyor screw shaft 12 and passes through it over its entire axial length. Within the feed hopper 50, the main screw shaft 33 is accommodated by the conveyor screw shaft 12 and completely surrounded by it.

[0033] The Fig. 3illustrates, in an enlarged view, the passage of the conveyor screw shaft 12 and the main screw shaft 33 mounted therein through the first passage opening 51 of the feed hopper 50. A bearing block 60 is arranged on an outer side 53 of the feed hopper 50, aligned with the first passage opening 51, which absorbs the radial and axial forces of both the conveyor screw shaft 12 and the main screw shaft 33. For this purpose, the bearing block 60 has a plurality of first conveyor screw bearings 61 arranged one behind the other in the axial direction x, which engage the conveyor screw shaft 12 from the outside. The main screw shaft 33 is supported relative to the conveyor screw shaft 12 by a first main screw bearing 62, which is also overlapped by the bearing block 60 in the axial direction x.

[0034] The conveyor screw shaft 12 is led out of the bearing block 60 on the side facing away from the feed hopper 50 and is connected to the Fig. 2 connected to the conveyor screw motor unit 11 shown. In the embodiment shown, the conveyor screw motor unit 11 has a drive motor 11a and a power transmission means 11b in the form of a chain, into which a pinion fixedly formed on the conveyor screw shaft 12 engages.

[0035] The main screw shaft 33 also emerges from the bearing block 60 on the side facing away from the feed hopper 50 and projects beyond the transport screw shaft 12 in the axial direction x. The main screw shaft 33 is accommodated at the end by the main screw motor unit 35.

[0036] For easy disassembly, for example, for cleaning or repair purposes, the conveyor screw 10 has a conveyor screw separation point 14, and the main screw 32 has a main screw separation point 36. The conveyor screw separation point 14 is formed in the immediate vicinity of the first passage opening 51 within the feed hopper 50 and is visible from above when the conveyor screw 10 is inserted into the comminution device, thereby considerably simplifying insertion. The main screw separation point 36 is offset in the axial direction x from the conveyor screw separation point 14 and is encompassed from the outside by the bearing block 60.The offset arrangement of the conveyor screw separation point 14 and the main screw separation point 36 in the axial direction x further simplifies installation, since the conveyor screw 10 with the main screw shaft 33 inserted therein can be pushed in axially in the assembled state and contact their separation points 14, 36 one after the other.

[0037] The Fig. 4 shows, in an enlarged view, the connection of the comminution module 20 to the second passage opening 52, in which the conveyor screw shaft 12 is rotatably received by means of a second conveyor screw bearing 64 supported by the centering insert 63. The second conveyor screw bearing 64 is formed from a bearing sleeve, against the outer side of which the centering insert 63 and the inner side of the hollow conveyor screw shaft 12 rest. The inner side of the bearing sleeve forms a second main screw bearing 65, on which the outer side of the main screw shaft 33 is supported.

[0038] The shredding module 20 also has a pre-shredding drum 40, which is attached to the cutting drum 30 at its end. An end of the pre-shredding drum 40 facing away from the cutting drum 30 engages the second through-opening 52 at its end. On an inner side 41, the pre-shredding drum 41 is provided with a surface consisting of fields 42 and grooves 43. The grooves 43 form a spiral groove running through the fields 42 and provide a wave-like surface. The main screw flight 34 of the section of the main screw 32 running axially through the pre-shredding module 40 transports the food to be shredded towards the cutting drum 30, wherein the food to be shredded undergoes pre-shredding at the fields 42 and grooves 43. List of reference symbols

[0039] 10Conveyor screw 11Conveyor screw motor unit 11aDrive motor 11bPower transmission means 12Conveyor screw shaft 13Conveyor screw gear 14Conveyor screw separation point 20Crushing module 30Cutting drum 31Cutting openings 32Main auger 33Main auger shaft 34Main auger gear 35Main auger motor unit 36Main auger separation point 37Residue discharge opening 38Residue chute 39Food discharge 40Pre-shredding drum 41Inside of pre-shredding drum 42Fields 43Trains 50Feed hopper 51First opening 52Second opening 53Outside of feed hopper 54Mixing shaft 60Bearing block 61First conveyor screw bearing 62First main screw bearing 63Centering insert 64Second conveyor screw bearing 65Second main screw bearing 70Machine frame 71Support feet xaxial direction

Claims

1. A shredder device for foodstuffs comprising a feed hopper (50), a screw conveyor (10) running at least in sections through the feed hopper (50) and a shredder module (20) following the screw conveyor (10) in an axial direction (x), wherein the screw conveyor (10) comprises a screw conveyor shaft (12) driven by a screw conveyor motor unit (11) and having a screw conveyor flight (13) integrally formed thereon in sections, and the shredder module (20) comprises a cutting drum (30) having cutting openings (31) formed therein, and a main screw (32) rotatably arranged in the shredder module (20) having a main screw shaft (33), which is driven by a main screw motor unit (35), and a main screw flight (34), which is formed thereon and passes over the cutting openings (31), wherein the main screw shaft (33) is coaxially enclosed by the screw conveyor shaft (12) inside the feed hopper (50) up to the shredder module (20), and wherein the feed hopper (50) has a first and second passage opening (51, 52) on opposite sides through which the screw conveyor shaft (12) and the main screw shaft (33) are passed, characterized in that a centering insert (63) is inserted into the second passage opening (52), in which the screw conveyor shaft (12) is rotatably supported by means of a second screw conveyor bearing (64) and the main screw shaft (33) is rotatably supported by means of a second main screw bearing (65).

2. The shredder device according to claim 1, characterized in that only the main screw shaft (33) of the main screw (32) is enclosed by the screw conveyor shaft (12).

3. The shredder device according to claim 1 or 2, characterized in that the screw conveyor shaft (12) is designed as a closed tubular body in the axial extension.

4. The shredder device according to one of claims 1 to 3, characterized in that the screw conveyor motor unit (11) and the main screw motor unit (35) are arranged on a side of the screw conveyor (10) facing away from the shredder module (20).

5. The shredder device according to one of claims 1 to 4, characterized in that the shredder module (20) is fastened on the front side around the second passage opening (52).

6. The shredder device according to one of claims 1 to 5, characterized in that the screw conveyor shaft (12) and the main screw shaft (33) are mounted in a common bearing block (60).

7. The shredder device according to claim 6, characterized in that within the axial direction (x) of the bearing block (60) the screw conveyor shaft (12) is rotatably supported by means of several first screw conveyor bearings (61) with respect to the bearing block (60) and the main screw shaft (33) is rotatably supported by means of at least one first main screw bearing (62) relative to the screw conveyor shaft (12).

8. The shredder device according to claim 7, characterized in that the first screw conveyor bearings (61) and the at least one first main screw bearing (62) are designed as roller bearings.

9. The shredder device according to one of claims 6 to 8, characterized in that at the bearing block (60) the screw conveyor shaft (12) has a screw conveyor disconnection point (14) and the main screw shaft (33) has a main screw disconnection point (36).

10. The shredder device according to one of claims 6 to 9 as far as dependent on claim 5, characterized in that the bearing block (60) is arranged on an outside (53) of the feed hopper (50) around the first passage opening (51).

11. The shredder device according to one of claims 1 to 10, characterized in that the second screw conveyor bearing (64) and the second main screw bearing (65) are designed as slide bearings.

12. The shredder device according to one of claims 1 to 11, characterized in that the shredder module (20) comprises a pre-shredding drum (40) which is arranged in the axial direction (x) between the cutting drum (30) and the second passage opening (52).

13. The shredder device according to claim 12, characterized in that lands (42) and grooves (43) are formed on an inner side (41) of the pre-shredding drum (40).