CONCHING DEVICE AND METHOD FOR CONCHING A PRODUCT MASS

Description

[0001] The present invention relates to a conching device and a method for conching a product mass. Conching devices and corresponding methods are known from documents DE 198 35 347 A1, DE 196 36 989 A1, DE 196 37 098 A1, GB 2 523 271 A, DE 42 21 315 A1, US 5 707 145 A, DE 44 33 039 A1, and DE 36 03 155 A1.

[0002] A conching device (also called a conche) is a device for processing a food product mass, particularly in chocolate production. With such a device, raw materials such as cocoa mass, sugar, cocoa butter, and / or milk powder can be blended and processed in a manner known to those skilled in the art by exerting compression and / or shear forces. The latter is also commonly referred to as conching and serves, among other things, to remove moisture and thus substances with undesirable properties, such as acetic acid or aldehydes.

[0003] Conching is an important process step that can significantly determine the quality and flavor of the final product. Furthermore, it is a relatively time-consuming process step, resulting in a correspondingly high energy requirement.

[0004] It has been shown that the desired product quality cannot always be achieved with the known devices and methods, especially if this is to be done efficiently and in an energy-saving manner.

[0005] The invention is therefore based on the object of providing a conching device and a method for conching a product mass which enable high product quality with improved efficiency.

[0006] To solve this problem, the invention proposes a conching device having the features specified in claim 1 and a method having the features specified in claim 11.

[0007] The conching device according to the invention comprises a container that forms a receiving space for a product mass. The container can be closed or at least partially open. In other words, the receiving space can essentially completely surround the product mass. However, the receiving space and / or container can also be at least locally interrupted and open by openings or feed channels.

[0008] The receiving space can be defined by an inner container wall and / or an inner cross-section of the container. The inner container wall and thus the receiving space can also be heated or cooled, for example via channels and / or pipes arranged in the container wall through which a heated fluid is conducted. The container can have a substantially similar shape to the receiving space. In other words, the shape of the outer cross-section of the container can substantially correspond to the shape of its inner cross-section, at least over a large part of its axial length, whereby the latter can form the receiving space.

[0009] The product mass may comprise at least one of the following ingredients: cocoa mass, sugar, cocoa butter, milk powder, and fat. In general, it may be a fat-based product mass for the production of luxury foods, in particular for the production of chocolate.

[0010] According to the invention, the conching device further comprises a shaft that is at least partially accommodated in the container and designed to rotate about its longitudinal axis. The shaft can also extend at least partially through the receiving space. In one embodiment, the shaft extends substantially centrally through the container and / or receiving space and, in particular, such that the container and / or receiving space extend substantially rotationally symmetrically around the shaft. Deviations from the rotational symmetry can arise due to local openings or feed channels in the container and / or the receiving space.

[0011] Within the scope of the present disclosure, the terms "axial" and "radial" may refer to the longitudinal axis of the shaft, unless otherwise stated or apparent. Furthermore, within the scope of the present disclosure, it may generally be contemplated that the shaft's longitudinal axis corresponds to a horizontal plane in space, so that the radial extensions may refer to a vertical plane in space. The terms "above" and "below" may refer to a position vertically above or vertically below the shaft's longitudinal axis or a horizontal plane containing the shaft's longitudinal axis. For example, a position below the shaft's longitudinal axis may refer to a position between the shaft's longitudinal axis and a floor area in the vicinity of the conching device.

[0012] The shaft may be substantially cylindrical and / or elongated. Furthermore, the shaft may extend from one end to an opposite end of the container or receiving space, and optionally beyond, to be supported on both sides within the device.

[0013] The conching device further comprises at least one conching tool coupled to the shaft for joint rotation, such that the conching tool is moved in a first rotational direction along an orbit during a conching operation of the device. In other words, it is provided that the conching operation of the device is characterized by a predetermined rotational direction of the shaft and thus a predetermined rotational direction of the conching tool. The rotational direction of the conching tool can relate in particular to a rotational direction of its active surface explained below. As also explained below, a discharge operation of the device for discharging the product mass from the receiving space can also be provided.During this discharge operation, the shaft can rotate opposite to the direction of rotation of the conching operation and the conching tool can thus move along the orbit in a second direction of rotation opposite to the first direction of rotation.

[0014] The orbit along which the conching tool is moved can run concentrically around and in particular circularly around the longitudinal axis of the shaft. The conching tool can further comprise a positioning section and an active surface. The positioning section can extend substantially radially from the shaft and arrange the active surface with a desired orientation and / or a desired distance relative to the inner wall of the container. The active surface can also extend at an angle to the positioning section. Specifically, the invention provides that the active surface of the conching tool faces the inner wall of the container. According to one variant, the active surface further extends at a relatively shallow angle of, for example, between 0° and 40° relative to the longitudinal axis of the shaft or else parallel thereto.

[0015] The active surface can be the section of the conching tool that performs the desired processing of the product mass during conching and interacts with it for this purpose. For example, the active surface can be designed to exert the compression and / or shear forces required for conching on the product mass. Accordingly, the orbit of the conching tool can be defined as the orbit of its active surface during rotation of the shaft.

[0016] In general, the conching device can also comprise a plurality of conching tools, each of which is coupled to the shaft and can rotate therewith in a predetermined manner. For example, more than three conching tools can be provided, and in particular at least four, at least five, or at least six conching tools. In this context, the conching tools can be arranged relative to one another such that their active surfaces are lined up along the shaft without any significant axial spacing and / or slightly overlap axially. This makes it possible to achieve a substantially axially continuous covering of the container's inner wall or, in other words, a virtually gap-free axial processing of the product mass along the shaft.

[0017] The active surface is further designed such that a radial gap between the inner container wall and the active surface decreases at least in sections when viewed counter to the first direction of rotation. The active surface can thus be designed such that the product mass is compressed and / or sheared at least in sections, since the space between the active surface and the inner container wall increasingly narrows as the movement progresses in the first direction of rotation. More precisely, the product mass can initially pass between the active surface and the inner container wall via a comparatively large radial gap, although this gap narrows as the shaft continues to rotate in the first direction of rotation. This means that compression and / or shear forces can be exerted on the product mass.Overall, a gap between the active surface and the inner wall of the container can thus be essentially wedge-shaped or funnel-shaped, at least in sections.

[0018] In other words, the active surface during conching operation can comprise an inlet-side region through which the product mass enters a gap between the active surface and the container's inner wall. The active surface can also comprise an outlet-side region located downstream of the inlet-side region, viewed opposite the first direction of rotation. A radial distance (or in other words, a radial gap) between the active surface and the container's inner wall can decrease, at least in sections, between the inlet-side and outlet-side regions.

[0019] In other words, the effective surface can be designed such that a radial gap between the inner wall of the container and the effective surface is at least temporarily reduced when sweeping over a predetermined section of the fixed inner wall of the container, which can in particular be point-shaped.

[0020] It is understood that the radial gap between the active surface and the inner container wall can also expand again in certain sections. This can occur, in particular, in a region that, viewed opposite to the first direction of rotation, is located downstream of an active surface section with a narrowing radial gap. In other words, the active surface can be designed such that the radial gap expands again, at least in certain sections, after compression and / or shearing of the product mass. This can particularly apply to a region of the active surface on the outlet side during conching operation.

[0021] In general, the active surface can comprise a curved region opposite the container inner wall, and in particular a convexly curved region. The active surface can thus be shaped such that it curves or bulges toward the container inner wall. In general, the active surface can comprise recesses, inclined regions, or guide surfaces to achieve a desired product flow through the space between the active surface and the container inner wall. However, it is also conceivable for the active surface to have a substantially smooth and closed surface.

[0022] A further development of the invention provides that the active surface has a recess extending along the orbit. The recess can be defined by opposing edge regions of the active surface, which can, for example, be inclined relative to the recess. In other words, the edge regions can form inclined sidewall regions of the recess. The recess can define a guide region or, in other words, a guide channel that extends along the orbit. This can enable a product mass flow along the active surface and along the orbit.

[0023] In this context, it can further be provided that a width of the recess, which extends substantially transversely to the orbit, increases when viewed along the first direction of rotation. The increase in width can occur in steps or continuously through a variable or constant increase. The recess can therefore be generally funnel-shaped or wedge-shaped, whereby it can narrow when viewed opposite to the first direction of rotation. Accordingly, a guide region or guide channel defined by the recess can narrow when viewed opposite to the first direction of rotation, which can promote the generation of the desired compression and / or shear forces.

[0024] The conching tool can further comprise a stripper which is at least partially spaced apart from the active surface when viewed along the orbit. In particular, the stripper can be located downstream of the active surface when viewed opposite to the first direction of rotation and / or can only slightly overlap therewith along the orbit. The active surface can, for example, assume a forward position during conching operation compared to the stripper when viewed in the first direction of rotation. In other words, during conching operation, the stripper can be closer to an outlet-side region of the active surface than to an inlet-side region. Consequently, during conching operation, the stripper can be designed to interact substantially with product mass that has already been processed by the active surface within the current movement or rotation cycle of the conching tool.

[0025] The scraper can generally be designed to remove product mass adhering to the container's inner wall and / or to convey it in a desired direction. The scraper can be arranged at a distance of less than 3 mm, less than 2 mm, approximately 1 mm, or less from the container's inner wall. Compared to the active surface of the conching tool, the scraper can be designed with a significantly smaller surface area opposite the container's inner wall. This surface can, in particular, be essentially linear and, for example, occupy less than 25%, less than 10%, or less than 5% of the area defined by the active surface of the conching tool.

[0026] In this context, it can further be provided that the scraper is arranged on the active surface via a spacer, wherein the spacer is designed in particular to allow a radial passage of product mass. The spacer can extend substantially parallel to or along the orbit and arrange the scraper along the orbit at a predetermined distance from the active surface. The spacer can comprise at least one rod, at least one profile, or another suitable structure.

[0027] The passage of the product mass can refer in particular to a product mass volume that, viewed along the orbit, is located between the wiper and the active surface. The wiper can enable the passage of this product mass volume in the direction of the shaft. For this purpose, the spacer can comprise an opening or generally not completely cover an area between the wiper and the active surface.

[0028] Without limitation to the features explained above in connection with the scraper, the scraper can also be elastically preloaded against the inner container wall. Preloading can generally be elastic, in particular such that the scraper rests against the inner container wall with a predetermined contact pressure. For this purpose, the scraper can be hingedly connected to the active surface and / or the conching tool and resiliently urged toward the inner container wall. In this way, a small distance or even contact between the scraper and the inner container wall can be achieved, whereby manufacturing tolerances of the container are compensated for due to the preloading of the scraper.

[0029] The wiper and the active surface can also extend along a common section of the shaft's longitudinal axis. In other words, the wiper and the active surface can at least partially overlap axially or even substantially completely overlap, for example, they can be configured with a matching axial length. One embodiment provides that the wiper protrudes axially beyond the active surface by no more than 50%, or by no more than 25%, or by no more than 10%, relative to the axial length of the active surface.

[0030] The scraper can further be oriented such that, at least upon rotation of the conching tool in a second direction of rotation opposite to the first direction of rotation, it generates a product mass flow in the direction of a product outlet of the container. The second direction of rotation can be a direction of rotation in the aforementioned discharge operation of the conching device. In this case, the scraper can be angled in a preferred manner, for example, relative to the longitudinal axis of the shaft, and thus generate a preferred product mass flow. The product outlet can, in particular, be arranged axially centrally on the container and on its underside.

[0031] With a plurality of conching tools, the scrapers can each be individually aligned according to the position of the conching tools along the shaft's longitudinal axis. In particular, they can each be aligned such that the product mass flow described above can be generated in the direction of the container center. For example, scrapers arranged on either side of the product outlet or the container center can be aligned opposite and / or mirrored to each other in order to be able to convey the product mass in the direction of the product outlet. The term "container center" can generally refer to an axial central region of the container and / or the receiving space.

[0032] The scrapers can therefore perform different functions depending on the shaft's rotation direction. During discharge, they can support the fast and efficient discharge of the product mass, whereas during conching, they can remove product residue from the inner wall of the container.

[0033] The device can further comprise at least one deflection tool coupled to the shaft for common rotation, wherein the deflection tool, in particular with optional cooperation with an adjacent container inner wall, is designed to generate a product mass flow toward a container center. The product mass flow toward the container center can be generated at least during conching operation of the device. Compared to the active surfaces of the conching tools, the deflection tool can have a significantly smaller surface area opposite the container inner wall (for example, less than 25%, less than 10%, or less than 5% of the active surface area). This surface can also be substantially linear or elongated.

[0034] The deflection tool can be arranged on the shaft at an axial distance from the conching tool. An active surface of the deflection tool, which interacts with the product mass for deflection, can in turn be radially spaced from the shaft via a positioning section of the deflection tool.

[0035] According to one embodiment, at least two deflection tools are provided, which are arranged at opposite axial ends of the receiving space and / or the shaft. All conching tools can be arranged axially between the at least two deflection tools. Accordingly, the deflection tools can be designed to convey product mass from the axial end regions of the receiving space back toward the center of the container in order to generate a preferred product mass flow within the receiving space.

[0036] The deflection tool can achieve the product mass flow essentially solely by means of an active surface specially aligned for this purpose. According to one embodiment, however, the product mass flow is generated essentially in cooperation with the adjacent inner container walls and in particular with an adjacent axial end region of the receiving space. The deflection tool can be aligned such that, during conching operation, it initially pushes the product mass further axially outwards and thus away from the container center, whereupon the product mass is redirected by the inner container walls towards the container center. The product mass flow can be returned towards the container center in particular in a region near or above the longitudinal axis of the shaft.

[0037] More generally, the inventor has recognized that the deflection tool can be used to create a preferred product flow within the receiving space, which can, among other things, lead to more intensive aeration of the product mass.

[0038] According to the invention, the length of the receiving space along the shaft's longitudinal axis is greater than the radial extent of the receiving space. Viewed in a section containing the shaft's longitudinal axis (hereinafter also referred to as a "longitudinal section"), the receiving space can thus be formed with a substantially elongated shape, for example, as an elongated ellipse.

[0039] In addition, it can be provided that a radial extent of the receiving space increases from each axial end of the receiving space towards a region of the largest cross-section of the receiving space, wherein a product outlet and / or air outlet is arranged in particular in or near the region of the largest cross-section. The increase in the radial extent can be substantially uniform, variable, or stepped. The largest cross-section can be a region that encompasses a largest radial extent of the container, for example a largest diameter. In other words, it can be a region that encompasses the largest inner circumference of the receiving space around the longitudinal axis of the shaft. The largest cross-section can further form a plane of symmetry of the receiving space, wherein the receiving space can be designed to be substantially mirror-symmetrical to this plane of symmetry.

[0040] According to a variant, the receiving space, viewed in the longitudinal section explained above, is essentially elliptical, diamond-shaped or designed as a double cone in which the base surfaces of the cones are placed next to one another.

[0041] In this case, a major axis of the ellipse, rhombus, or double cone shape can coincide with the longitudinal shaft axis. Additionally or alternatively, a minor axis of the ellipse, rhombus, or double cone shape can coincide with a radial extension of the longitudinal shaft axis and, in particular, define the largest cross-section of the receiving space.

[0042] Within the scope of the present disclosure, the container can be generally stationary, with the shaft with the conching tools attached thereto being moved relative to the container within its interior. The air outlet and / or the product outlet can therefore also be generally stationary within the conching device. For example, the product outlet can generally be arranged on an underside of the container, which can face a floor area in the vicinity of the conching device. Likewise, the air outlet can be arranged on an upper side of the container, which faces away from the floor area. In other words, the product outlet can be arranged below the longitudinal axis of the shaft and / or the air outlet can be arranged above the longitudinal axis of the shaft.

[0043] In one embodiment, the air outlet and the product outlet can be substantially opposite one another or, in other words, positioned on mutually opposite inner wall regions of the container. The product outlet and the air outlet can each provide an opening to the environment, which can also be opened and closed, for example via a valve device. The optional proximity to the region of the largest cross-section can mean an axial distance of no more than 2 m, no more than 1 m, no more than 50 cm, or no more than 20 cm. In particular, it can be provided that at least the product outlet is arranged directly in the region of the largest cross-section and the air outlet is only slightly axially spaced therefrom.

[0044] The inner walls of the container can define conveyor or guide slopes to direct the product mass toward the product outlet. By arranging the air outlet in the area of ​​the largest cross-section, a deliberately large distance from the product mass fill level within the receiving space can be achieved. This can, for example, limit the discharge of dust into the environment during conching.

[0045] According to the invention, the container further comprises an air inlet which is positioned such that it is arranged below a filling level of the product mass during conching operation, and / or wherein the air inlet is positioned below the longitudinal axis of the shaft.

[0046] Accordingly, it can be provided that, during conching, the product mass is filled up to a maximum of a predetermined fill level. The air inlet is located below this predetermined fill level. This, in turn, can involve positioning it on or near a bottom of the container, which faces a floor area in the vicinity of the conching device.

[0047] Overall, this allows for the introduction of air below the fill level into the product mass, as well as fatty additives, which can also be fed in via the air inlet. The inventor recognized that this approach allows for better mixing and thus a more comprehensive removal of bitter substances from the product mass.

[0048] In general, the air inlet can be designed such that the air supplied via it, or any other additives, can be fed to the product mass essentially in the first direction of rotation. For this purpose, the air inlet comprises a feed channel. In other words, the air inlet enables the supply of air or additives to the product mass essentially tangentially to the first direction of rotation and / or to the orbit of the conching tool and / or to the adjacent container inner wall. The term "essentially tangential" can refer to a vector component of the feed direction that runs tangentially to the first direction of rotation, the orbit, or the container inner wall significantly exceeding a vector component running transversely thereto, in particular by at least two, three, or four times.

[0049] Without being limited to the features previously explained in connection with the air inlet, it is further conceivable for the air inlet to comprise an at least partially constricted region and / or a throttle device. This region or this throttle device can be arranged near a transition region between the air inlet and the receiving space or directly in this transition region. An example of a suitable throttle device is a metal sheet that locally constricts the cross-section of the air inlet in the transition region to the receiving space. In general, these variants enable the flow velocity of the air supply to be specifically increased due to the cross-sectional constriction of the air inlet. This makes it possible, for example, to achieve more effective drying of the product mass.This also allows for more effective removal of dirt in the area of ​​the air inlet, particularly in the transition area discussed above.

[0050] The conching device can further comprise a compressed air unit configured to supply compressed air to the container via the air inlet, in particular such that the compressed air supply occurs substantially in the first direction of rotation. The compressed air unit can comprise a nozzle through which compressed air can be selectively blown into the air inlet. The nozzle can be positioned and / or dimensioned such that additional additives, for example in the form of greases or cleaning agents, can also be supplied through the air inlet.

[0051] The term "compressed air" can also encompass pressurized gases or gas mixtures other than conventional ambient air. The supply in the first direction of circulation can refer to the tangential supply explained above. The supplied compressed air can have an air pressure of, for example, 0.1 to 0.3 bar above ambient pressure.

[0052] Furthermore, in this context, the conching device may comprise a heating unit configured to heat the air supplied via the air inlet. This may, in particular, involve heating the air before it is supplied or blown into the receiving space, for example, heating it within a compressed air reservoir.

[0053] The device may further comprise a weight detection unit configured to detect the weight of the container, including the product mass contained therein, during operation of the device. This may be the weight of the product mass during the conching process, for example, to monitor moisture and thus weight loss of the product mass. The weight detection unit may comprise a so-called load cell for this purpose.

[0054] The conching device may further comprise a control device configured to control and / or regulate the conching operation based on detection signals from the weight detection unit. For example, the control device may be configured to control at least the rotational speed of the shaft, the total duration of the conching operation, the timing or amount of air supply, and a temperature of the heatable container walls based on the detected weight and, in particular, a detected weight loss.

[0055] The invention further relates to a method for conching a product mass, in particular by means of a device according to one of the preceding aspects, which comprises the steps specified in claim 11.

[0056] In general, the method may include any further step and any further feature to achieve all of the advantages and interactions explained above. For example, the method may further include a step of processing the product mass using the active surfaces of the conching tool during conching and / or a step of discharging the product mass using the conching tool's stripper described above during discharging.

[0057] According to the invention, the method comprises the step of supplying air and / or a fat-containing additive below a filling level of the product mass through an air inlet of the container tangential to the first direction of circulation.

[0058] The method may also include the step of detecting the weight of the product mass contained in the container, in particular to determine the degree of dehumidification of the product mass. For this purpose, the total weight of the container and the product mass contained therein may be detected, whereupon the weight of the product mass contained therein, and in particular its weight loss during the conching operation, can be calculated by subtracting the known empty container weight. The method may further include a step of controlling the conching operation according to the detected weight, wherein the control may relate to the parameters discussed above with reference to the control device.

[0059] The method may further comprise the step of reversing the direction of rotation of the conching tool in order to convey the product mass out of the container. This may occur within the scope of the discharge operation discussed above. Reversing the direction of rotation may involve moving the conching tool in a second direction of rotation opposite to the first direction of rotation. In this context, a further step of opening a product outlet may be provided so that the product mass can exit via the product outlet. This may involve opening a valve device of the product outlet.

[0060] Finally, the method may further comprise the step of adding a predetermined portion of a total amount of a fatty additive only during the discharge of the product mass from the container. This allows the fatty additive to assume a cleaning function to effectively remove residues of the product mass from the receiving space of the container.

[0061] Preferred embodiments of the invention are explained in more detail below with reference to the accompanying schematic drawings. They show: Figure 1 shows a longitudinal sectional view of a conching device according to a first embodiment; Figure 2 shows a perspective detail view of the shaft of the conching device from Figure 1 ; Figure 3 a perspective detail view of a conching tool of the conching device from Figure 1 ; Figure 4 a cross-sectional view of the device from Figure 1to explain a conching operation of the device; Figure 5 shows a perspective detail view of a conching tool according to a further embodiment; and Figure 6 shows a flow chart of a method according to the invention.

[0062] In Figure 1 A conching device according to a first embodiment of the invention is shown and generally designated 10. The conching device 10 is supported on a horizontal floor surface in its surroundings via supports 12. The conching device 10 further comprises two lateral frame assemblies 14, which are spaced apart from one another and each supported by one of the support units 12. Extending between the frame assemblies 14 is a cylindrical shaft 16, which is rotatably mounted in each of the frame assemblies 14. The shaft 16 runs along a longitudinal shaft axis L, along which the frame assemblies 14 are spaced apart from one another.

[0063] In the Figure 1left frame assembly 14, the shaft 16 is coupled to a drive unit 18. The drive unit 18 is designed to drive the shaft 16 for rotation about its longitudinal axis L. In the Figure 1 In the right frame arrangement 14, the shaft 16 is rotatably mounted about its longitudinal axis L in a bearing unit 20.

[0064] The conching device 10 further comprises a container 22 extending between the frame assemblies 14 along the shaft's longitudinal axis L. The container 22 is fixedly coupled to the frame assemblies 14 and is generally hollow. More specifically, the container 22 forms a receiving space 24 defined by corresponding interior walls of the container 22. The container 22 and the receiving space 24 are closed, except for the openings explained below.

[0065] In Figure 1It can be seen that the container 22 accommodates that section of the shaft 16 which extends between the frame assemblies 14 and between the drive unit 18 and the bearing unit 20. The shape of the container 22 further corresponds to the shape of the receiving space 24 or, to put it another way, the outer cross-section of the container 22 substantially corresponds to the inner cross-section of the receiving space 24. In the case shown, the container 22 and thus also the receiving space 24 are substantially rotationally symmetrical to the shaft longitudinal axis L, wherein the shaft longitudinal axis L is concentrically accommodated in the container 22 and extends through it. An axial length A of the receiving space 24 formed by the container 22 further exceeds a maximum radial extension E of the receiving space 24.

[0066] Specifically, it can be seen that the radial extent E of the receiving space 24 increases from a first axial end region 26 near the drive unit 18 to a region 28 of a largest cross-section or, in other words, a largest radial extent E. In the same sense, a radial extent E increases starting from a second axial end region 30 of the receiving space 24 near the bearing unit 20 in the direction of the region 28 of the largest cross-section. In other words, a radial extent E of the receiving space 24 increases continuously starting from its respective axial ends 26, 30 towards the region 28 of the largest cross-section. The receiving space 24 is therefore elliptical, wherein the smaller ellipse axis of the Figure 1The shape of the receiving space 24 can also be described as a double cone with adjacent base surfaces and rounded tips in the end regions 26, 30. The tips can, for example, be spherically rounded or alternatively also be designed as flat ends. Finally, it should be noted that the region 28 of the largest cross-section forms a plane of symmetry running orthogonal to the longitudinal shaft axis L. The receiving space 24 is essentially mirror-symmetrical to this plane of symmetry.

[0067] Note that the container 22 in Figure 1 comprises two container halves 23, 25, which, however, are not joined together in the region 28 of the largest cross-section. Instead, the Figure 1right container half 25 is characterized by a greater axial length and extends from the right axial end region 30 axially beyond the region 28 of the largest cross-section. Figure 1 The left container half 23, on the other hand, extends from the left axial end region 26 in the direction of the other container half 25. The container halves 23, 25 are assembled and connected to one another along a flange 27 surrounding the longitudinal axis L of the shaft.

[0068] This container structure with two container parts or halves 23, 25 of different axial length, which are assembled outside the region 28 of the largest axial cross-section, represents in itself an independent aspect of the invention and is not limited to a combination with the further features of the present embodiment.

[0069] In the area 28 of the largest cross-section, an air outlet 32 ​​is arranged on an upper side facing away from the floor area and the support units 12. At an opposite location and thus facing the floor area and the support units 12, a product outlet 34 with a selectively openable and closable valve device is arranged. Furthermore, Figure 1 a filling funnel 36, through which a product mass to be processed or its raw materials can be filled into the receiving space 24.

[0070] The shaft 16, whose longitudinal axis L forms a horizontal line in space in the illustrated case, is rotatable about its longitudinal axis L relative to the stationary container 22 by means of the drive unit 18. At its section accommodated in the container 22, the shaft has several conching and deflection tools 38, 40. The exact arrangement and number of these tools 38, 40 is shown in the perspective individual illustration of Figure 2clearly, in which the positions of the drive and bearing unit 18, 20 of the conching device 10 are also indicated.

[0071] In Figure 2 It can be seen that the shaft 16 has a deflection tool 40 at its axial ends near the end regions 26, 30 of the receiving space 24 as well as near the drive or bearing unit 18, 20. The deflection tool 40 comprises a curved deflection section 42, which is arranged at a predetermined radial distance from the shaft 16 via a positioning section 44. The deflection section 42 has a substantially linear surface 47 facing the inner wall of the container. As can be seen in Figure 1recognizes, it is inclined in a predetermined manner relative to the shaft longitudinal axis L, so that it can generate a desired product mass flow within the receiving space 24. Along the shaft longitudinal axis L and axially between the deflection tools 40, a total of six conching tools 38 are arranged at uniform axial distances R1 from one another. With the exception of their positioning along the shaft longitudinal axis L and in the circumferential direction of the shaft 16, the conching tools 38 are largely identical to one another. A further exception to this is, for example, the alignment of strippers 62 of the respective conching tools 38, explained below. For reasons of clarity, Figure 1 and 2 Not all of the features explained below are always provided with separate reference symbols for all of the conching tools 38.

[0072] The conching tools 38 each comprise a positioning section 46, which extends radially from the shaft longitudinal axis L in the direction of an opposite container inner wall. The positioning section 46 has a substantially round cross-section near the shaft 16, which merges into a flattened area 48. An orientation of the flattened area 48 is individually selected to reduce flow resistance depending on the position of the conching tool 38 along the shaft longitudinal axis L (see Figure 2 ).

[0073] At a radially outer end of the flattened region 48, a bottom side of a working area 50 of the respective conching tool 38 is arranged. The working area 50 extends at an angle to the positioning section 46 and along an opposite container inner wall. Furthermore, the working area 50 comprises an active surface 52 facing the container inner wall (see also Figure 1 ).

[0074] The structure and function of this active surface 52 is explained below using Figure 4 explained. Figure 4 shows a cross-sectional view of the conching device 10 from Figure 1 , where a position of the section plane AA in Figure 1 Container 22 is in Figure 4 shown only schematically and with a cross-section open at the top.

[0075] In Figure 4 First, one can see the shaft 16, with the shaft longitudinal axis L perpendicular to the plane of the sheet. Furthermore, a deflection tool 40 and a conching tool 38 are shown. Figure 4 one can also see the positioning section 46 extending radially from the shaft 16 and the working area 50 of the conching tool 38 arranged thereon. Finally, it can be seen that the active surface 52 faces the inner wall of the container, which defines the receiving space 24.

[0076] The active surface 52 has a first region 54 and a second region 56, which are spaced apart from one another along the inner circumference of the container 22. More specifically, the conching device 10 is designed to rotate the shaft 16 in a first rotational direction R1 during a conching operation and consequently also to move the deflection and conching tools 38, 40 coupled thereto in this direction. The active surface 52 of each conching tool 38 is moved relative to the container inner wall in a first circumferential direction U1.

[0077] The working area 50 and in particular the effective surface 52 of each conching tool 38 is moved along a circular orbit 58 around the shaft longitudinal axis L along the inner wall of the container. The course of such an orbit 58 is shown in Figure 2shown schematically, whereby this orbit 58 is assigned to the third conching tool 38 from the left in this figure. For the sake of completeness, it should be mentioned that in Figure 1 When moving in the first rotational and orbital direction R1, U1, the lower two conching tools 38 move in the direction of the viewer.

[0078] Returning to Figure 4 It can be seen that the first region 54 of the active surface 52, viewed in the first direction of rotation U1, is located upstream of the second region 56. In other words, the first region 54 forms an inlet-side region of the active surface 52 during conching operation of the device 10, whereas the second region 56 forms an outlet-side region.

[0079] Accordingly, one recognizes in Figure 4that a radial gap S1, S2 or, in other words, a radial distance S1, S2 between the active surface 52 and the container inner wall varies in the first circumferential direction U1. More precisely, the size of this radial gap S1, S2 decreases from the first to the second region 54, 56, so that an intermediate space between the active surface 52 and the container inner wall 22 increasingly narrows (see Fig.4 : S1>S2). One can see in Figure 4 but also that this gap S3 increases again in an effective area 60, wherein the effective area 60 is located downstream of the second area 56 opposite to the first direction of rotation U1.

[0080] In summary, the effective surface 52 is designed such that, at least during conching operation and during a movement in the first direction of rotation U1, a radial gap S1, S2 between the effective surface 52 and the container inner wall is reduced at least in sections. Consequently, one can see in Figure 4 that the space delimited by the active surface 52 and the container inner wall is essentially wedge-shaped or funnel-shaped and tapers and narrows when viewed opposite to the first rotational direction U1. With continued rotation of the shaft 16 in the direction R1, successive inner circumferential sections of the container 22 are thus swept over by the active surface 52. From the perspective of a fixed point on the container inner wall, this results in an at least temporary reduction of the radial gap S1, S2.

[0081] Further details on the structure and function of the active surface 52 of each conching tool 52 can be found in Figure 3 . There it can be seen that the effective surface 52 comprises an axially centrally arranged depression 53, which extends along the orbit 58 and thus in the direction of rotation U1 of the effective surface 52. The position of the shaft longitudinal axis relative to the effective surface 52 results from Figure 1. Furthermore, one can see in Figure 3 that an axial width B of the recess 53 decreases when viewed opposite to the direction of rotation UI. In other words, the recess 53 tapers increasingly, which is advantageous for generating compression and / or shear forces on the product mass to be processed. The recess 53 is further surrounded by edge regions 55 of the active surface 52, which also extend along the orbit 58 and centrally receive and delimit the recess 53. The edge regions 55 are inclined relative to the plane of the recess 53.

[0082] In the following, referring to Figure 2It can be seen that the conching tools 38 further each comprise a stripper 62. This is coupled to the working area 50 of a respective conching tool 38 via a spacer 64. More precisely, the stripper 62 comprises a linear surface 65 facing the inner wall of the container and a planar area 66 extending substantially radially to the inner wall of the container. The spacer 64 is connected to the active surface 52 near the widening area 60 of the latter (see also Fig. 4 ).

[0083] In the present case, the spacer 64 comprises a first section 66, which extends axially along the active surface 52, as well as two sections 68 projecting therefrom in the circumferential direction (see Figure 2, right half). Overall, the spacer 64 extends at a substantially constant distance from the opposite inner container wall. The sections 68 running in the circumferential direction are dimensioned differently, so that the wiper 62 and in particular its surface 65 facing the inner container wall are aligned in a predetermined manner. For example, one can see the two lower wipers 62 in Figure 1 that they are inclined opposite to each other and relative to the longitudinal axis L of the shaft.

[0084] In summary, the spacer 64 serves to couple the stripper 62 with the active surface 52 of a respective conching tool 38. Furthermore, the spacer 64 is Figure 2The sections 68 shown are designed to arrange the wiper 62 with a predetermined orientation and at a predetermined distance relative to the active surface 52 and the container inner wall. Alternatively or additionally, the wiper 62 can also be elastically prestressed against the container inner wall, which can be achieved, for example, via a suitable resilient device between the wiper 62 and the active surface 52.

[0085] As can be seen from Figure 4 As illustrated, the wiper 62 is located downstream of the effective surface 52, viewed opposite to the first direction of rotation U1. Furthermore, the spacer 64 and the wiper 62 define an opening 70, which allows a radial passage of product mass. Figure 1 Finally, it can be seen that the wiper 62 and the active surface 52 span a substantially identical axial section A1 of the shaft longitudinal axis L or, in other words, axially overlap along the section A1.

[0086] Based on the figures explained above, a conching operation of the conching device 10 is described below. The raw materials of the product mass to be processed are first fed into the container 22 via the filling hopper 36. This can be done manually or, particularly in larger systems, mechanically, for example, via separate pipe connections. In this case, the raw materials include cocoa mass, sugar, cocoa butter, and milk powder, from which a product mass for chocolate production is obtained. Figure 4 a product level P is schematically indicated, up to which the product mass in the container 22 increases.

[0087] Then, the shaft 16 is driven by the drive unit 18 in the first rotational direction R1, so that the conching tools 38 and in particular their active surfaces 52 are moved in the first rotational direction U1 along their respective orbit 58. When the active surfaces 52 move below the shaft longitudinal axis L, a certain portion of the product mass enters the space between the active surface 52 and an opposite area of ​​the container inner wall. Due to the Figure 4 Due to the narrowing gap S1, S2 between these elements, this portion of the product mass is subjected to increasing compression pressure and / or shear forces (so-called conching). This leads to the desired blending and mixing of the product mass and, in particular, the gradual removal of bitter substances.

[0088] A possible path Z of a corresponding product mass fraction is shown schematically in Figure 4indicated. It can be seen that path Z extends along the active surface 52 and then enters the area of ​​the scraper 62. The scraper 62 is designed to detach a portion of the product mass that has already been processed by the active surface 52 from the container's inner wall. Likewise, a portion of the product mass that has already been processed can pass radially through the opening 70 between the spacer 64 and the scraper 62.

[0089] In Figure 1 It can also be seen that the conching tools 38 are positioned along the shaft longitudinal axis in such a way that they each span directly adjacent axial sections A1 of the shaft 16. Figure 1 not all corresponding axial sections A1 are entered. In other words, the product mass can be processed axially by the conching tools 38 practically without gaps. Figure 4product level P, it is understood that the processing of the product mass only takes place when the active surfaces 52 are located below the shaft longitudinal axis L. This applies to the Figure 1 Conching tools 38 positioned below the shaft longitudinal axis L, whereas the conching tools 38 positioned above the shaft longitudinal axis L are arranged above the product level P and thus outside the product mass.

[0090] Furthermore, one can see in Figure 1 that the deflection tools 40, of which in Figure 1only one can be seen, generate a product mass flow U during rotation in conching operation, which presses the product mass to a respective adjacent axial end region 26, 30 of the receiving space 24. This results in the product mass being continuously deflected according to the arrow U during conching operation via the axial end regions 26, 30 in the direction of the container center. The container center means an axial center comprising the region 28 of the largest cross-section. Specifically, the product mass is guided from a region below the longitudinal shaft axis along the inner walls of the container to approximately the level of the longitudinal shaft axis L or even beyond, from where it flows to the container center.

[0091] The container 22 further comprises two stripping rollers 33, each arranged near one of the axial end regions 26, 30. The stripping rollers 33 are designed to interact with the axially outer conching tools 38 and strip off any product mass adhering thereto.

[0092] By continuing the rotation of the shaft 16 for several minutes or hours, the product mass can be conched.

[0093] The following also describes the air supply during the conching process. Figure 1 It can be seen that the container 22 comprises at least one air inlet 72 on each side of its axial center. According to further embodiments, however, at least two, at least four, or at least six air inlets 72 can be provided on each side of the axial center. The air inlet 72 is also arranged below the shaft longitudinal axis L. This is further illustrated by Figure 4, in which it can also be seen that the air inlet 72 is also positioned below the product level P. The air inlet 72 defines a supply channel which is aligned such that the air can be introduced into the receiving space 24 and into the product mass received therein essentially tangentially to the adjacent container inner wall, the first circulation direction U1 and an active surface 52 moved along the air inlet 72.

[0094] The air supply can be done via a Figure 4 This can be done by means of a schematically indicated compressed air unit 74, which can heat the air to a predetermined temperature before feeding it by means of a heating unit 75. Fat-containing additives below the product level P can also be added through the air inlet 72.

[0095] Furthermore, in Figure 1A blower 76 of the compressed air unit 74 is shown, which is arranged within one of the lateral frame assemblies 14 of the conching device 10. A connecting channel between the blower 76 and the air inlets 72 is not shown, but can be provided in the usual way via pipes, hoses, or fluid channels.

[0096] In Figure 4 Furthermore, an optional throttle device 73 is indicated by dashed lines, which in the illustrated case is formed as a sheet metal component. The throttle device 73 is arranged in the transition area between the air inlet 72 and the receiving space 24 and constricts the flow cross-section of the air inlet 72 there. This increases the flow velocity of the supplied compressed air, making it easier to remove contaminants from the transition area and drying the product mass more effectively.

[0097] Finally, it should be noted that the conching device 10 comprises a weight detection unit in the form of a Figure 1 may include a schematically indicated load cell 78. This can detect a weight of the container 22 together with the product mass filled therein in a known manner and, from this, also detect a change in the weight of the product mass within the container 22 during the conching and / or discharge operation. Based on this, the progress of the conching or discharge operation can be monitored and the operation of the device 10 can be suitably adjusted via a control unit (not shown).

[0098] Furthermore, there is a difference between the Figure 1 , 2 and 4 a slight deviation in that in the case of Figure 1 and 2 a transition area between the conching tools 38 and the shaft 16 is designed in the shape of a base. A corresponding transition base 67 is in Figure 2For example, one of the conching tools 38 is provided with a separate reference symbol. In the case of Figure 4 For reasons of simplicity, such transition bases 67 are not shown, but are also provided there. In principle, however, it is conceivable to optionally design the conching device 10 without such transition bases 67.

[0099] Based on the Figure 1 and 4 In the following, a discharge operation of the conching device 10 is described. In the discharge operation, the drive shaft 16 is rotated in a direction of rotation R2 opposite to the first direction of rotation R1 (see Figure 4 ). Consequently, the conching tool 38 is also made of Figure 4 and in particular, its active surface 52 rotates in a direction U2 opposite to the first direction of rotation U1. This means that the product mass essentially interacts with the scraper 62 and is largely guided away from the active surface 52.

[0100] Specifically, one can see in Figure 1 that the scrapers 62 of the conching tools 38 are each aligned such that, upon corresponding rotation of the shaft 16 in the direction of rotation R2, they generate a product mass flow P2 in the direction of the container center or the largest radial cross-section 28. This results in the product mass being able to be quickly conveyed out of the container 22 via the axially centrally arranged product outlet 34. This is further supported by the elliptical longitudinal section of the receiving space 24 explained above. Due to this shape, the inner walls of the container define guide slopes near the product outlet 34, so that the product mass flows towards the product outlet 34 under the influence of gravity.

[0101] In Figure 5a conching tool 38 according to an alternative embodiment of a conching device 10 according to the invention is shown. In comparison to the first embodiment, features with the same or similar functions are designated by the same reference numerals. The conching tool 38 again comprises a positioning section 46, at the radially outer end of which a working area 50 of the conching tool 38 is arranged. This differs from the first embodiment in that the active surface 52 is formed with a flat and convexly curved active surface 52 in the direction of the opposite container inner wall. A radius of curvature of the active surface 52 and / or an orientation of the working area 50 relative to the inner wall is selected such that a radial gap narrowing is again achieved during conching operation, as described above with reference to Figure 4 explained.

[0102] In Figure 5A scraper 62 can also be seen, which is arranged downstream of the active surface 52, viewed opposite to the first direction of rotation U1. This is achieved via a spacer 64, which comprises two webs 68 extending substantially parallel to the inner wall of the container. The scraper 62 is again aligned via the spacer 64 in such a way that the conveying effect described during discharge operation is achieved in the direction of the product outlet 34.

[0103] Based on Figure 6 Finally, an example of the sequence of a method according to the invention is described. In a first step S1, the container 22 is filled via the filling hopper 36 with the raw materials forming the product mass, here essentially cocoa mass, sugar, cocoa butter, and milk powder. This can again be done manually or, especially in larger systems, mechanically, for example, via suitable pipe connections.

[0104] Subsequently, in a second step S2, the shaft 16 is driven in the first rotational direction R1 to mix the individual components into a mixture that is as homogeneous as possible and to loosen this mixture. This step S2, also referred to as premixing, can involve driving the shaft 16 for three to ten minutes.

[0105] In step S3, a so-called dry conching process is carried out while the shaft rotation continues. In this process, additional hot air is drawn in via the air inlets 72 from Figure 4blown into the product mass below the product level P. This promotes mixing and the removal of bitter substances. Due to the essentially tangential supply of the air, which is also preheated to a specific temperature, the distribution of the air within the product mass is also improved. Depending on the desired product quality and the properties of the product mass, this step can last significantly longer than the premixing according to step S2.

[0106] The air supply can take place at predetermined time intervals during step S3. At the same time, air and the moisture contained therein are discharged via the air outlet 32 ​​of the container 22 (see Figure 1 ). This leads to an increasing weight loss of the product mass, which is measured by the load cell 78 from Figure 1The recording of this weight reduction (or the resulting degree of dehumidification) is Figure 3 shown as a separate step S4. However, this step can also overlap with step S3 or be performed entirely in parallel. Furthermore, the conching operation of step S3 can be continuously adjusted to the detected weight reduction. A typical weight loss after a completed dry conching can, for example, be approximately 1% of the weight of the original product mass.

[0107] During dry conching in step S3, the product mass can contain a maximum fat content of 23%, and in particular between 12% and 15%. However, this can vary depending on the product mass and the final product to be produced. When producing dark chocolate, for example, the addition of milk powder can be omitted, thus increasing the fat content.

[0108] Up to and including steps S3 and S4, no further liquid or fat is added, so that the product mass is processed only with the described supply of hot air. In step S5, however, a fatty additive is added, which leads to a liquefaction of the product mass as the shaft 16 continues to rotate in the first rotation direction R1. As described, this fatty additive can be added via the tangential air inlets 72 below the product level P. Furthermore, when fed via the air inlets 72, any product adhesions present therein can also be loosened, thus cleaning the air inlets 72.

[0109] Once conching is complete, the discharge operation of the conching device 10 can begin in step S6. As described above, the shaft 16 is driven in the opposite second rotational direction R2, so that the scrapers 62 convey the product mass toward the axially central product outlet 34. The valve arrangement of the product outlet 34 is opened. Furthermore, a predetermined portion of the total fatty additive to be added can be added only in this step or shortly before in order to prevent product mass residues from adhering to the inner wall of the container and to achieve the most complete emptying of the container 22. Using this method, it was achieved, for example, that less than 0.5% and in particular less than 0.2% or less than 0.1 percent of the total mass remains in the container 22.

[0110] The cleaning operation can then begin in step S7. This can start automatically when the product emptying described above has taken place, which in turn can be determined by detecting a decrease in the weight of the product mass in the container 22. Cleaning of the container 22 can be carried out with water, grease or other suitable cleaning agents. In this case, a negative pressure can also be created within the container 22 in step S8. This lowers the boiling point of the water and, in addition, promotes the discharge of remaining product mass and / or cleaning agent from the container 22. The supply of cleaning agent can in turn take place via the tangential air inlets 72 and / or via cleaning heads that are arranged near the rollers 33 in Figure 1 are arranged.

[0111] In step S8, the receiving space 24 of the container 22 is then dried. This can be achieved by generating a vacuum, rotating the shaft 16, supplying hot air, and / or heating the container walls. Finally, it should be noted that steps S2 and S4, in particular, are purely optional.

Claims

1. A conching device (10), comprising: - a container (22) forming a receiving space (24) for a product mass, - a shaft (16) at least partially accommodated in the container (22) and configured to rotate about its longitudinal axis (L), wherein a length (A) of the receiving space (24) along the longitudinal axis (L) of the shaft is greater than a radial extension (E) of the receiving space (24), and - at least one conching tool (38) which is coupled to the shaft (16) for common rotation so that the conching tool (38) moves in a first direction of rotation (U1) along a path of rotation (58) during a conching operation of the conching device (10), characterized in that the container (22) has an air inlet (72) for supplying air and / or a fat-containing additive, wherein the air inlet (72) comprises a supply channel configured to supply air and / or a fat-containing additive tangentially to the first direction of rotation (U1) and / or to the path of rotation of the conching tool (38) and / or to the inner wall of the container (22), wherein the air inlet (72) is positioned such that it is arranged below a filling level (P) of the product mass and / or below the longitudinal axis (L) of the shaft during conching operation.

2. The conching device according to claim 1, wherein the receiving space (24) has a largest cross-section (28) in an area viewed in direction of the longitudinal axis (L), the radial extension (E) of the receiving space (24) increases from each axial end (26, 30) of the receiving space (24) towards the area of the largest cross-section (28) of the receiving space (24), and a product outlet (34) and / or an air outlet (32) is arranged in or near the area of the largest cross-section (28).

3. The conching device according to claim 1 or 2, wherein the area (28) of the largest cross-section of the receiving space (24) forms a symmetry plane orthogonal to the longitudinal axis (L).

4. The conching device according to one of claims 1 to 3, wherein the receiving space (24) is formed in an elliptical shape and the smaller ellipse axis corresponds to the radial extension (E).

5. The conching device according to one of claims 1 to 4, wherein the product outlet (34) is arranged at a bottom of the container (22) and / or the air outlet (32) is arranged at a top of the container (22).

6. The conching device according to one of the preceding claims, wherein the conching tool (38) comprises a scraper (62) and the scraper (62) is aligned such that it generates a flow of product mass towards a product outlet (34) of the container (22) at least during a rotation of the conching tool (38) in a second direction of rotation (U2) opposite to the first direction of rotation (U1).

7. The conching device according to one of the preceding claims, wherein the conching device (10) further comprises at least one deflection tool (40) coupled to the shaft (16) for common rotation, wherein the deflection tool (40), in particular with optional cooperation with an adjacent inner wall of the container, is configured to generate a flow of product mass towards a container center.

8. The conching device according to one of the preceding claims, wherein the conching device comprises a compressed air unit (74) configured to supply compressed air to the container (22) through the air inlet (72), in particular such that the compressed air supply occurs substantially in the first direction of rotation (U1).

9. The conching device according to claim 8, wherein the conching device (10) further comprises a heating unit (75) configured to heat the air to be supplied via the air inlet (72).

10. The conching device according to one of the preceding claims, wherein the conching device (10) comprises a weight detection unit (78) configured to detect a weight of the container (22) including the product mass contained therein during operation of the conching device (10).

11. A method for conching a product mass, in particular by means of a conching device (10) according to one of the preceding claims, comprising the steps of: - filling a product mass into a receiving space (24) formed by a container (22), the length (A) of which along the longitudinal axis (L) of the shaft is greater than a radial extension (E) of the receiving space (24), wherein the container (22) has an air inlet (72) for supplying air and / or a fat-containing additive, wherein the air inlet (72) comprises a supply channel configured to supply air and / or a fat-containing additive tangentially to the first direction of rotation (U1) and / or to the path of rotation of the conching tool (38) and / or to the inner wall of the container (22), - rotating a shaft (16) at least partially received in the container (22) about its longitudinal axis (L), and - moving a conching tool (38) coupled to the shaft (16) for common rotation in a first direction of rotation (U1) along a path of rotation (58), and - supplying air and / or a fat-containing additive tangentially to the first direction of rotation (U1) and / or to the path of rotation of the conching tool (38) and / or to the inner wall of the container (22) through the air inlet (72) and below a filling level (P) of the product mass and / or below the longitudinal axis (L) of the shaft.

12. The method of claim 11, further comprising the step: - detecting a weight of the product mass contained in the container (22).

13. The method according to any one of claims 11 or 12, further comprising the step: - reversing the direction of rotation (U1, U2) of the conching tool (38) to convey the product mass out of the container (22).

14. The method according to any one of claims 11 to 13, further comprising the step: - supplying a predetermined proportion of a total amount of a fat-containing additive to be supplied only during discharge of the product mass from the container (22).