EP4367045A1

EP4367045A1 - Drive unit for product hold-down element

Info

Publication number: EP4367045A1
Application number: EP22735488.3A
Authority: EP
Inventors: Denise Wetter; Christian Baumeister
Original assignee: Weber Food Technology GmbH
Current assignee: Weber Food Technology GmbH
Priority date: 2021-07-06
Filing date: 2022-07-06
Publication date: 2024-05-15
Also published as: WO2023280930A1

Abstract

The invention relates to a drive unit (1) for a product hold-down element (51) of a food cutting machine (73) for driving a transport means (55) of a product hold-down element (51). The drive unit (1) comprises a driveshaft (3), a gearbox (5) having a gear housing (7) with a first and a second side (13, 15), a motor (9), and a torque support (11). The drive shaft (3) is connected to the gearbox (5) and is designed to drive a transport means (55). The motor (9) is connected to the gearbox (5) so that a rotation of the motor (9) is transmitted to the drive shaft (3) by means of the gearbox (5). The drive shaft (3) and the motor (9) are connected to the gearbox (5) on the first side (13) of the gearbox housing (7). The gearbox housing (7) is mounted on the torque support (11) on the second side (15).

Description

Drive unit for product hold-down device

The present invention relates to a drive unit for a product hold-down device, a product hold-down device including the drive unit, a food slicing machine including the product hold-down device, a food processing line and a method for producing a drive unit.

Food slicing machines usually have a product feed, which feeds a food product, for example an oblong loaf of cheese or a sausage, to a cutting blade. For this purpose, the food product is usually guided on a product support in the form of a conveyor belt, with a product hold-down device being able to press on the food product from above in order to achieve precise advancement. The product hold-down device expediently also includes a drivable conveyor belt which is in contact with the food product.

Product hold-down devices are known from US Pat. No. 9,950,869 B1 and WO 2010/011237 A1, which have drivable conveyor belts, for which purpose an electric motor is used, the rotation of which is transmitted to a drive shaft of the respective conveyor belt by means of a toothed belt. For this purpose, the electric motor is arranged laterally outside the extension of the drive shaft.

A packaging machine with conveyor belts for a product support is known from US 2013/0008133 A1, in which the power is transmitted from the electric motor to the drive shaft by means of a gear, with the electric motor and the drive shaft being on the same side of the gear.

The known variants for driving a conveyor belt, in particular a product hold-down device, are technically complex, take up a relatively large amount of space or have disadvantages with regard to the mechanical bearing and force dissipation.

The object of the invention is to provide a drive unit for a product hold-down device that is improved in terms of dimensioning and operating properties, as well as a method for producing such a device.

A drive unit according to the invention for a product hold-down device of a food slicing machine for driving a transport means of a product hold-down device comprises a drive shaft, a gear with a gear housing with a first and a second side, a motor, and a torque arm. The drive shaft is connected to the gearbox and designed to drive a means of transport. The motor is connected to the gearbox so that rotation of the motor is transmitted to the drive shaft via the gearbox. The drive shaft and the motor are connected to the transmission on the first side of the transmission housing and the transmission housing is mounted on the torque arm on the second side. The means of transport is in particular a circulating means of transport, for example a transport belt or a transport chain, or a transport roller. The arrangement of the motor and drive shaft on the same side of the gearbox housing saves a lot of space. The arrangement makes it possible to deflect the rotation of the drive, ie the motor, in particular by between 150° and 210°, advantageously by essentially 180°. Advantageously, all components of the drive train, ie in particular the engine, transmission and drive shaft, are mounted together on the torque support via the outer, opposite, second side of the transmission housing. Consequently, in particular the desired strength, in particular torsional strength, can be achieved. Advantageously, greater elasticity with regard to a tilting of the transmission housing relative to the normal direction of extension of the drive shaft can be made possible than with regard to a rotation of the transmission housing about the drive shaft, so as not to strain the transmission. The second side of the gear case may be opposite the first side of the gear case.

The transmission can have a gear ratio i=1 to i=16, in particular i=8, with the input speed being reduced on the output side. The gearbox can be two-stage or multi-stage. In particular, an odd number of stages is provided. This allows the input and output torques to be compensated in order to keep the bearing torques on the torque arm low. However, an even number of stages can also be provided. Then the torque arm can be used advantageously to derive higher bearing torques.

The gear can have a mass moment of inertia related to the drive of the gear of J tot of 0.05 _kgcm ² to 0.5 kgcm ² , in particular of 0.113 kgcm ² . The gear has angular play, i.e. backlash, which is smaller than the play between the drive shaft and the means of transport, and can therefore make a significant contribution to improved cutting quality through a more precise product drive when the product is fed. The rapid reversal of the conveying direction and changes in speed when products are advanced and/or retracted in the infeed area of a food slicing machine can thus be managed more precisely. To protect against the ingress of water, the gear housing can be watertight. The gear can be provided with a lubricant that is approved for the food industry, in particular with silicone oil, polyalphaolefin (PAO) or white oil. The gear shafts can be mounted using ball bearings, in particular deep groove ball bearings. The gearbox housing can be made of aluminum. The transmission housing can have a length of 100 mm to 250 mm, in particular approx. 166 mm, a width of 50 mm to 100 mm, in particular approx. 70 mm and a height of 50 mm to 100 mm, in particular approx. 87 mm exhibit. That Transmission housing can be chamfered at its corners, which means that more installation space is available. The motor can be a servo motor.

The torque arm is preferably more elastic in the axial direction of the drive shaft than in the radial direction of the drive shaft. On the one hand, this achieves a sufficiently stable positioning of the transmission with a torsional strength. On the other hand, a certain elasticity is ensured in the axial direction of the drive shaft in order not to distort the transmission. The elasticity of the torque support in the axial direction of the drive shaft is in particular at least twice as high, advantageously at least 4 times as high as in the radial direction of the drive shaft.

In an advantageous embodiment, the torque support is flat, in particular essentially X-shaped, Y-shaped or T-shaped. The main extension surface of the torque arm can extend perpendicularly to the axial direction of the drive shaft and parallel to the second side of the transmission. The rigidity of the torque arm can be adjusted based on the thickness of the torque arm, but also through its shape. The extension of the area of the torque support in length and width can also depend on the position of the drive unit. As described in more detail below with reference to the figures, the torque arm can be axisymmetric. However, the torque support can also be asymmetrical, in particular extending in different directions in different lengths, in order to achieve a desired arrangement of the drive unit, in particular a particularly space-saving arrangement, an arrangement along an arc of a circle or according to predetermined housing dimensions. For example, the individual legs of an X-shaped, Y-shaped or T-shaped torque support can be of different lengths.

The torque support is preferably made of metal, in particular metal with a thickness in the range from 0.8 to 2.0 mm. The torque arm can be a metal sheet, that is to say it can have a significantly greater width and length than its thickness, for example of the order of a few centimetres. In particular, the sheet metal can have a thickness of 1.5 mm. Such dimensions and materials result in advantageous mechanical properties, in particular greater elasticity in the axial direction of the drive shaft than in its radial direction.

In a preferred variant, the transmission housing has two or more spaced-apart fastening means for connection to the torque support, so that the transmission housing can be positioned in at least two different positions relative to the torque support. The fastening means can be, for example, a screw mount or a group of screw mounts with an internal thread in order to fasten the torque arm to the transmission housing by means of a screw connection. Different positioning of the gearbox housing relative to the torque arm, and thus also of the drive shaft and motor relative to the torque arm, can be achieved by connecting a torque arm of a specific shape to one of the two or more fasteners. Furthermore, different forms of torque supports can be used in order to achieve different positioning of the transmission housing relative to the torque support with one or more fastening means. Likewise, an asymmetric reaction arm can be flipped or rotated to provide another location option for the gear housing. The fastening means are provided in particular in the area of the second side of the transmission housing. However, they can also be provided elsewhere on the transmission housing.

In this way, the transmission housing can be arranged depending on the spatial restrictions, for example due to a housing. In particular, a standardized drive unit can be provided for use in different machine types, with different spatial requirements due to the machine types being taken into account in the form and arrangement of the torque supports used. Thus, a simple, standardized manufacture of drive units is possible, in which only different shapes of torque supports have to be manufactured in order to correspond to different machine types. However, the torque supports can be produced easily and inexpensively from sheet metal, for example by stamping or laser cutting.

In a further advantageous variant, the drive shaft can be connected to the transmission by means of a plug connection. A particularly simple installation is thus possible. In addition, prefabricated units made up of motor and transmission, so-called motor-transmission units, can be connected to the drive shaft in a particularly simple manner.

A toothed sleeve is preferably arranged on the drive shaft, which can be displaced and clamped on the drive shaft by means of a ring clamping element. The sleeve rotates as a result of the rotation of the drive shaft and is intended for engagement with a circulating transport means, which can be a toothed belt in particular, in order to drive it. The sleeve can thus be freely positioned on the drive shaft and the drive unit can be adapted to the requirements of different machine types. In particular, multi-track product hold-down devices can be manufactured with a corresponding number of drive units, with the sleeve only having to be moved to the respective track position in order to drive the corresponding transport means. Instead of toothed belts, other transport belts, such as flat belts or V-belts, can also be used, and the sleeve can have the appropriate surface structure. In a further variant, the torque support is attached to a frame element. The frame element can be part of the drive unit and can be provided, for example, as a support for installing the drive unit in the product hold-down device. Alternatively, the frame element can be part of a product hold-down device or a frame of a food slicing machine. The frame element takes care of dissipating the forces that are applied to the torque support, in particular the torque or weight of the transmission, the motor and the drive shaft. The torque support and frame element can be connected by a screw connection.

In an expedient variant, the motor, the transmission, and the torque arm are enclosed by a housing. This protects the components from contamination and splashing water when cleaning the food slicing machine. The housing may have an openable cover so that an opening is provided through which access to the interior of the housing and maintenance or replacement of the components is possible. Due to the opening in the housing and the compact design of the components, the plug-in connections of the electric motors in particular are easily accessible. A seal is expediently present at the point of contact between the cover and the rest of the housing.

The housing preferably has a sealed through-opening through which the drive shaft is guided. The drive shaft outside the housing can therefore drive a means of transport for the product hold-down device, and the components inside the housing, i.e. gears and motor, are protected from dirt and splashing water.

Preferably, the drive unit has two or more drive shafts, each of which is connected to a gearbox, each gearbox being connected to a motor, so that a rotation of the motor is transmitted to the respective gearbox and the respective drive shaft, the drive shafts in the Are arranged essentially along a circular arc. The product hold-down device can thus have multiple lanes and due to the arrangement, the drive units and the other components of the product hold-down device can be structurally identical. In particular, all circulating means of transport can be of the same length. For this purpose, a deflection roller of a carrier frame, which can be provided in a product hold-down device for each track and serves to guide the circulating transport means, can be aligned with those of the other carrier frames along one axis. Thus several food products can be conveyed side by side or several carrier frames and thus means of transport for one food product can be provided.

The respective torque supports, on which the respective transmission housings are mounted, can expediently have a different shape from the other torque supports. So each individual position of the gear, for example along an arc of a circle. Additionally or alternatively, the torque supports can each be connected to differently positioned fastening means of the transmission housing.

In one embodiment, the drive unit has a second frame element on which the drive shaft is mounted. The drive shaft can be connected to the second frame element with its side opposite the transmission in the axial direction. Thus, the drive shaft is also stably mounted at both ends. The drive unit can also have a spar which connects the first frame element, to which the torque support is attached, and the second frame element. As a result, the drive unit is additionally mechanically stabilized. The spar can be designed in the form of a round tube, a square tube, a square profile, a flat strut or the like. The bar can be provided in order to anchor a support frame of the product hold-down device. The spar can have a scale, which serves as a positioning aid for the support frames and the sleeves of the drive shafts. In addition, a strut can be provided, which is connected to the first and the second frame element and serves as an additional bearing for the support frames.

A product hold-down device according to the invention comprises a drive unit according to one of the above-described embodiments, a carrier frame and a means of transport, the means of transport being mounted in the carrier frame and the carrier frame being mounted on the drive unit by means of a strut. During operation, the product hold-down device is lowered to such an extent that the means of transport presses on the food product from above with a desired force. The means of transport is in particular a circulating means of transport, for example a transport belt or a transport chain, or a transport roller. The powered transport aids in conveying the food product toward the cutting blade. The circulating transport means can be guided over deflection rollers of the support frame and over the sleeve of the drive shaft of the drive unit in order to be driven by the drive shaft.

A food slicing machine according to the invention comprises a product hold-down device and a cutting knife for slicing a food product.

A food processing line according to the invention comprises a food slicing machine and at least one upstream food product conveying device and/or at least one downstream food portioning device.

A method according to the invention for producing a drive unit comprises the following method steps:

connecting an engine to a transmission on a first side of a transmission case into an engine transmission unit; connecting the motor transmission unit to a drive shaft on the first side of the transmission housing; and

Connecting a second side of the transmission case to a torque arm.

In particular, the method steps can be carried out in the aforementioned order.

This means that prefabricated motor-gear units can be kept in stock and installed on site in a particularly simple manner. The motor gear units are uniform and can be used for different machine types. The respective geometry of the machine types can then be taken into account, for example, by selecting the appropriately shaped torque arms.

Exemplary embodiments of the invention are described in more detail below with reference to the figures. show it

Figure 1: a perspective view of a first embodiment of a

drive unit,

Figure 2: a schematic view of torque supports in different forms,

Figure 3: a perspective view of a second embodiment of a

drive unit with housing,

Figure 4: another perspective view of the second embodiment of the drive unit,

Figure 5: a side view of the second embodiment of the drive unit,

FIG. 6: another side view of the second embodiment of the drive unit, FIG. 7: a perspective view of a product hold-down device,

FIG. 8: a schematic view of a food processing line comprising a food slicing machine with a product hold-down device.

Corresponding components are each provided with the same reference symbols in the figures.

Figure 1 shows a drive unit 1 with a drive shaft 3, a gearbox 5, which is encapsulated in a gearbox housing 7, a motor 9 and a torque arm 11. The drive shaft 3 and the motor 9 are on a first side 13 of the gearbox housing 7 with the gearbox 5 connected. The torque arm 11 is connected to a second side 15 of the transmission housing 7 . The second side 15 of the transmission housing is turned away from the viewer in this view, so that the torque arm 11 is covered by the transmission housing 7 and is shown here in broken lines. The torque support 11 is X-shaped and is connected to a first frame element 17 at its lower end. On the opposite side of the transmission housing 7 is the drive shaft 3 these rotatably mounted on a second frame element 19 in this representation. A sleeve 21 , which can be a toothed sleeve 21 , for example, is arranged on the drive shaft 3 and is provided for driving a transport means in the form of a transport belt of a product hold-down device due to the rotation of the drive shaft 3 . The first frame member 17 may be part of the drive unit, a product hold down or other frame component of a food slicing machine. The drive shaft 3 is connected to the transmission 5 by means of a plug connection 23 . In its longest extension, the drive shaft 3 defines its axial direction A. Its radial direction R is defined perpendicularly to the axial direction A.

FIG. 2 shows a schematic view of torque supports 11 in different forms. The torque supports 11 are essentially all flat, i.e. their extension in length and width, which are in the plane of the drawing here, is significantly greater than their thickness, which is perpendicular to the plane of the drawing here. Variants a), b), and c) are essentially X-shaped, with different areas of material being left out. Variant d) is Y-shaped and variant e) is T-shaped, with the top bar being slanted. The torque supports 11 can have holes 25 in order to be connected to fastening means of the transmission housing 7 by means of a screw connection.

FIG. 3 shows a perspective view of a second embodiment of a drive unit 1, which comprises four drive shafts 3, each of which is driven by a motor 9 by means of its own gear 5, in order in turn to drive a transport belt. The sleeves 21 are all still in a right-handed position, but can be shifted to drive the transport belt of the corresponding track. Ring clamping elements 27 serve to fix the sleeves 21 in the respective position on the drive shaft 3 . The housing 29 has through openings 31 through which the drive shafts 3 are guided. The through openings 31 are watertight. A spar 33 connects the first frame element 17 and the second frame element 19 and thus gives the drive unit 1 additional stability or is used for the further assembly of carrier frames and attachment of the drive unit 1 in a product hold-down device. The spar 33 in the form of a tubular support has a scale 35 in order to facilitate positioning of support frames or sleeves 21 . A strut 37 is used for further storage of support frames.

FIG. 4 shows a perspective view of the second embodiment of the drive unit 1 with four drive shafts 3 with a viewing angle of the second sides 15 of the transmission housing 7, ie from a right-hand side. In order to make the arrangement and in particular the housing 29 as space-saving as possible, the gear housings 7 arranged in partly different orientations. In this way, a housing 29 that is as small as possible can be filled particularly advantageously. For this purpose, the torque supports 11 are designed in different sizes and shapes and are partly connected to the transmission housing 7 by different fastening means 39 of the latter. The torque supports 11 are attached to the first frame element 17 . In this example, the housing 29 has an access opening 41 in order to enable access to the components located in the housing 29 . A cover 43 shown here in dashed lines closes the access opening 41 in a watertight and reversible manner. For this purpose, it can be designed in the form of a door, flap or a completely removable cover with correspondingly appropriate connecting or holding elements. A motor 9 and a gearbox 5 each form a motor-gear unit 45.

FIG. 5 shows a side view of the second embodiment according to FIG its shape essentially follows this arrangement and the motors 9 and transmission housing 7 are arranged in the housing 29 in a space-saving manner.

FIG. 6 shows a side view of the second embodiment according to FIG. 3 looking from the right onto the housing 29 or the torque supports 11 and transmission housing 7. It can be seen that each torque support 11 has an individual size and shape. In this way, the respective position of the drive shafts 3 can be matched and the torque supports 11 can be attached to a common, straight first frame element 17 . It can be seen that the position of the gear housing 7 is determined by the size and shape of the torque supports 11 themselves, as well as by the attachment to different fastening means 39 on the second side 15 of the gear housing 7.

Figure 7 shows a perspective view of a product hold-down device 51 with a drive unit 1 comprising four drive shafts 3. Four support frames 53 are mounted on the strut 37 and the beam 33, in each of which a transport means 55 in the form of a transport belt is guided, of which only the transport belt 55 of the rearmost support frame 53 seen in the viewing direction. The transport belts 55 are guided over deflection rollers 57 of the carrier frames 53 and the sleeve 21 of the drive shaft 3 . For this purpose, the sleeves 21 are pushed onto the respective track position and fixed there by means of a ring clamping element 27 . For example, toothed sleeves 21 can be used, which come into engagement with a transport belt 55 in the form of a toothed belt. The product hold-down device 51 can also be attached in a food slicing machine via the bar 33 .

FIG. 8 shows a schematic view of a food processing line 71 comprising a food slicing machine 73. The Food slicing machine 73 includes a product hold-down device 51 in order to supply a food product 75, for example an oblong loaf of sausage or cheese, to a cutting blade 77 in a controlled manner. Stacks 79 of slices 81 of the food product are conveyed to a food portioning device 83 and placed in packaging trays, for example. A loading robot or a suitably arranged conveyor belt can be used for this. The filled packaging trays are sealed airtight in a sealing machine 85 . A food product conveyor 87 is located upstream of the food slicing machine 73 and feeds the food product 75 to it.

Claims

Expectations

1. Food slicing machine (73) comprising a product hold-down device (51) and a cutting blade (77) for slicing a food product (75), the product hold-down device (51) comprising a drive unit (1), a support frame (53) and a transport means ( 55), wherein the means of transport (55) is mounted in the support frame (53), and wherein the support frame (53) is mounted on the drive unit (1) by means of a strut (37), the drive unit (1) for driving the means of transport (55) of the product hold-down device

(51) is provided, wherein the drive unit (1) comprises a drive shaft (3), a gear (5) with a gear housing (7) with a first and a second side (13, 15), a motor (9), and a torque arm (11), wherein the drive shaft (3) is connected to the gearbox (5) and is designed to drive a means of transport (55), wherein the motor (9) is connected to the gearbox (5) so that rotation of the motor (9) is transmitted to the drive shaft (3) by means of the gearbox (5), the drive shaft (3) and the motor (9) being connected to the gearbox (5) on the first side (13) of the gearbox housing (7). are connected, and wherein the transmission housing (7) is mounted on the second side (15) on the torque arm (11).

2. Food slicing machine according to claim 1, wherein the torque arm (11) is more elastic in the axial direction (A) of the drive shaft (3) than in the radial direction (R) of the drive shaft (3).

3. Food slicing machine according to claim 1 or 2, wherein the torque support (11) is flat, in particular essentially X-shaped, Y-shaped or T-shaped.

4. Food slicing machine according to one of the preceding claims, wherein the torque arm (11) is made of metal, in particular metal having a thickness in the range of 0.8 to 2.0 mm. 5. Food slicing machine according to one of the preceding claims, wherein the gear housing (7) has two or more spaced-apart fastening means (39) for connection to the torque support (11), so that the gear housing (7) can be in at least two different positions relative to the torque support ( 11) is positionable.

6. Food slicing machine according to one of the preceding claims, wherein the drive shaft (3) can be connected to the gear (5) by means of a plug connection (23).

7. Food slicing machine according to one of the preceding claims, wherein on the drive shaft (3) a toothed sleeve (21) is arranged, which can be displaced and clamped on the drive shaft (3) by means of a ring clamping element (27).

8. Food slicing machine according to one of the preceding claims, wherein the torque arm (11) is fixed to a frame member (17).

9. Food slicing machine according to one of the preceding claims, wherein the motor (9), the gearbox (5) and the torque arm (11) are enclosed by a housing (29).

10. Food slicing machine according to claim 9, wherein the housing (29) has a sealed through opening (31) through which the drive shaft (3) is passed.

11. Food slicing machine according to one of the preceding claims, which has two or more drive shafts (3), each of which is connected to a respective gearbox (5), wherein each gearbox (5) is respectively connected to a motor (9) so that a Rotation of the engine (9) on the respective gear (5) and the respective drive shaft (3) is transmitted, wherein the drive shafts (3) are arranged substantially along a circular arc.

12. Food processing line (71) comprising a food slicing machine (73) according to any one of the preceding claims, and at least one upstream food product conveyor (87) and/or at least one downstream food portioning device (83). 13. Method of making a

Drive unit (1) for a product hold-down device (51) of a

Food slicing machine (73) for driving a transport means (55) of the product hold-down device (51), the drive unit (1) comprising a drive shaft (3), a gear (5) with a gear housing (7) with a first and a second side (13 , 15), a motor (9), and a torque arm (11), wherein the drive shaft (3) is connected to the transmission (5) and is designed to drive a means of transport (55), wherein the motor (9) with the Gear (5) is connected so that rotation of the motor (9) is transmitted to the drive shaft (3) by means of the gear (5), the drive shaft (3) and the motor (9) being on the first side (13) of the transmission housing (7) are connected to the transmission (5), and wherein the transmission housing (7) is mounted on the second side (15) on the torque support (11), the method comprising the method steps:

connecting an engine (9) to a transmission (5) on a first side (13) of a transmission housing (7) to form a motor transmission unit (45);

connecting the motor gear unit (45) to a drive shaft (3) on the first side (13) of the gear housing (7); and

Connecting a second side (15) of the gear housing (7) to a torque arm (11), the second side (15) of the gear housing (7) being opposite the first side (13) of the gear housing (7).

14. The method according to claim 13, wherein the torque arm (11) in the axial direction (A) of the drive shaft (3) is more elastic than in the radial direction (R) of the drive shaft (3).

15. The method according to any one of claims 13 or 14, wherein the drive unit (1) has two or more drive shafts (3), each of which is connected to a gearbox (5), each gearbox (5) being connected to a motor (9 ) is connected so that a rotation of the motor (9) is transmitted to the respective gearbox (5) and the respective drive shaft (3), the drive shafts (3) being arranged essentially along a circular arc.