Coating machine, filling device, system for coating a plurality of material layers, and method for additive manufacturing of

Abstract

The invention relates to a coating machine (10) for applying a plurality of layers of material to a carrier (31) of a machine tool (30), the coating machine (10) being configured to make a workpiece layer by layer from the coated layers of material wherein the coating machine (10) comprises a body (11) movable relative to the carrier (31) of the machine tool (30), a material reservoir (12) having a filling chamber (13) for storing the material (1), the material reservoir (12) being carried by the body (11); and a discharge device which is designed to empty the filling chamber (13) of the material reservoir (12) by a first movement of the filling chamber (13) relative to the body (11) in order to discharge the material (1) stored in the filling chamber (13) onto the carrier (31). The invention also relates to a filling device having a dispensing device. The filling device is driven by the movement of the coating machine.

Description

Technical Field

[0001] The present application relates to a coating machine for applying a material layer, a filling device for use with the coating machine, a system for coating a plurality of material layers, and a method for additive manufacturing of a workpiece. Background Art

[0002] In the prior art, one-shot processes for additively manufacturing three-dimensional workpieces are currently known, in which the workpiece is built up layer by layer from provided material.

[0003] For this purpose, a material layer of powdered material is usually applied to a carrier of the machine tool and then partially solidified to form a workpiece layer by means of site-specific irradiation, for example by melting or sintering individual material particles in the material layer.

[0004] When a workpiece layer has solidified, a new layer of unprocessed material is applied to the support or the produced workpiece layer, and then the fixed-point irradiation is carried out again.

[0005] In this way, the workpiece is formed layer by layer from the material applied to the carrier in the form of a plurality of material layers.

[0006] The process generally involves a coater spreading a quantity of raw material on a carrier to apply a layer of material of a predetermined thickness.

[0007] In the prior art, currently known coating machines move relative to a carrier of a machine tool and spread a certain amount of material on the carrier in a layer-forming manner by means of a spreading element, wherein the spreading element can be, for example, in the form of a brush or lip. For example, such coating machines are shown in DE202019103407U1 or EP2818305A1.

[0008] In order to improve production efficiency, some attempts have been made to reduce the number of movement paths of the coater so that after applying the first layer of material, the coater does not necessarily need to move back to a starting position or a refilling position with a fixed material storage before applying the next layer of material.

[0009] To achieve this purpose, DE202019103407U1 or EP2818305A1 provide known solutions, in which the coating machine includes a material storage device with a filling chamber, in which a certain amount of material is carried, and when needed, the material storage device applies the material to the carrier by driving a closing mechanism for opening and closing the lower discharge port of the filling chamber. Subsequently, the applied material can be spread in a layer-forming manner, especially during the movement of the coating machine, the coating machine returns to the starting position, where the material storage device can be refilled for the next cycle.

[0010] However, when the closing mechanism is actuated, problems may arise including, but not limited to, loss of functionality due to incomplete opening and / or closing of the discharge port, and uncontrolled or incomplete application of the stored material to the carrier. As a result, the material layer cannot be applied to the carrier as intended, which in turn negatively affects the production quality of the workpiece to be processed. Summary of the invention

[0011] It is therefore an object of the present invention to provide an improved possibility for the additive production of workpieces, in which the applied material layers can be applied reliably and in a controllable manner.

[0012] In order to solve this problem, the present invention provides a coating machine according to claim 1 , a filling device according to claim 11 and a system for coating material layers according to claim 15 .

[0013] A further object of the present invention is to provide an improved possibility for the additive production of workpieces.

[0014] In order to achieve this further object, the invention provides a method according to claim 16 .

[0015] The dependent claims refer to preferred embodiments, wherein each embodiment can be provided individually or in combination.

[0016] According to a first aspect of the present invention, a coating machine is provided for coating a plurality of material layers onto a carrier of a machine tool, the carrier being configured to produce a workpiece layer by layer from the coated material layers. To this end, the coating machine comprises a base body movable relative to the carrier of the machine tool; a material reservoir carried by the base body and having a filling chamber for storing material; and a coating device, the coating device being configured to empty the filling chamber of the material reservoir by a first relative movement of the filling chamber relative to the base body, so as to coat the material stored in the filling chamber onto the carrier.

[0017] The coating machine according to the first aspect of the present invention provides a particularly effective method for coating a material layer onto a carrier, during an additive manufacturing process, in particular by selectively melting or sintering the coated material layer, for example, during an SLM (Selective Laser Melting) process, the workpiece is stacked layer by layer by a laser beam processing device of a machine tool.

[0018] The material to be coated is usually in powder form, and preferably comprises a metallic material, such as aluminum, steel, titanium, a nickel-based alloy or any other alloy suitable for use in the SLM process.

[0019] When referring to a carrier, for example, in the process of applying a material to a carrier and applying a material layer to a carrier, all material layers and / or solidified workpiece layers previously applied to the carrier should also be included. Therefore, the situation where a new material layer is formed on a material layer and / or a workpiece layer already existing on the carrier should also be included.

[0020] In order to reduce the distance that the coater needs to move for each layer of material, the coater preferably carries a certain amount of material in a material reservoir so that it can be applied to the carrier when needed and a new layer of material can be applied to the carrier. In this way, the coater does not have to always return to the starting position at the fixed material dispenser, which itself will also apply a certain amount of material to the carrier.

[0021] Therefore, the coating machine provides a particularly advantageous possibility, that is, in the first relative movement process of the filling chamber as a whole, the stored material is completely emptied. Therefore, a particularly wear-free and particularly reliable operation of the coating machine is achieved, and the material stored in the material reservoir can always be completely emptied.

[0022] Therefore, the coating machine does not need any additional closing mechanism for opening and closing the filling chamber outlet opening. For example, such closing mechanisms are known from DE 20 2019 103 407 U1 or EP 2 818 305 A1, which use a movably mounted closing element to close and open the opening of the filling chamber towards the carrier.

[0023] These closing mechanisms are subject to greater loads due to the continuous contact with the material, which is usually in powder form and can deposit on the bearing points, guide joints, fits, etc. of the movable closing mechanism and impair its function. The vibrations that inevitably occur during the movement of the coating machine favor the formation of these deposits.

[0024] This can lead to increased wear of the closure mechanism and, in certain cases, to its blocking. As a result, the opening of the filling chamber can no longer be opened or closed as intended, which can result in uncontrolled dispensing of the material contained therein.

[0025] By emptying the filling chamber by the first relative movement, such a closure can be omitted, so that the stored material essentially does not come into contact with bearing points or guides of the coating machine, which would otherwise have a negative impact on them. This ensures functionality and, in particular, low-wear operation.

[0026] The first relative movement also ensures that the filling chamber is completely emptied as the filling chamber moves as a whole. In this way, the flow limit of powdered materials can usually be exceeded more easily than in a case where the filling chamber is essentially fixed and the lower opening is only opened / released by a closing mechanism, in which case the material in the filling chamber has the potential to be "wedged" or "stuck", resulting in so-called bridging, where the material cannot move or start to flow.

[0027] On the other hand, the movement of the filling chamber itself generates additional dynamic forces on the material, so that even poorly flowing materials, especially powdered materials, can be dispensed reliably and thoroughly.

[0028] In a preferred embodiment, the coating device comprises a rotatable support for supporting the material reservoir so that the material reservoir can be rotated relative to the base body about the rotation axis, so that the first relative movement for emptying the filling chamber is a rotation about the rotation axis.

[0029] In this way, a particularly efficient method for emptying the filling chamber is provided, during which the filling chamber can be moved, for example, from an initial position (opening generally vertically upwards) to an upper position (rotated 180°, opening generally vertically downwards). Thus, the material filled through the filling chamber opening is moved out of the filling chamber and applied to the carrier through the same opening under the effect of gravity. By completely "tilting" the filling chamber relative to the base body into the upper position, all the material stored in the filling chamber can be reliably charged without any residual material remaining in the filling chamber.

[0030] Preferably, the rotation axis is parallel to the surface of the carrier and orthogonal to the moving direction of the base body.

[0031] Therefore, preferably, the coating device is configured to rotate the filling chamber from an initial position in which the filling chamber is filled to an end position at a predetermined angle, wherein the predetermined angle is preferably 90° to 270°, particularly preferably 180°.

[0032] Preferably, the angular position of the filling chamber relative to the base body of the coating machine is expressed as a zenith angle between a filling chamber reference line fixed to the filling chamber and the vertical direction of the earth's gravitational field. In cross section, the reference line starts from the center point of the filling chamber, is perpendicular to the rotation axis, and passes through the opening of the filling chamber. In the initial position of the filling chamber, the zenith angle is preferably 0°, and in the end position of the filling chamber, the zenith angle is between 90° and 180°, particularly preferably 180°.

[0033] In a preferred embodiment, the coating machine comprises a spreading element connected to the base body, the spreading element being configured to spread a quantity of material placed on the carrier in a layer-forming manner by movement of the base body.

[0034] In this way, a certain amount of material, for example the material can be placed as a deposit on one end face of the carrier surface and spread onto the carrier by the spreading element, so that a particularly uniform application of the material layer is achieved.

[0035] Spreading mainly refers to sweeping or spreading the material. In this process, the spreading element pushes the accumulated material in front of the base body when it moves, and at the same time conveys the material through a predetermined size gap between the spreading element and the carrier, thereby spreading the material in the form of a layer.

[0036] In a preferred embodiment, the base body can be moved back and forth between a first and a second end position relative to the carrier, in particular in a translational manner, wherein the coating machine is configured to spread a first amount of material on the carrier in a layer-forming manner using a spreading element by a first movement of the base body from the first end position to the second end position, and is further configured to empty the filling chamber of the material reservoir by a first relative movement so as to apply a second amount of material to the carrier when the second end position or a coating position located between the first and second end positions is reached.

[0037] Preferably, the coating machine is configured to spread a second amount of material in a layer on the carrier by means of the spreading element during a second movement of the base body from the second end position to the first end position, which material is applied to the carrier when reaching the second end position or coating position.

[0038] This avoids unnecessary movement of the coating machine and allows two material layers to be coated in one reciprocating cycle from the first end position to the second end position and back again. The design of the coating device has the advantage that the coating of the material for forming the second layer can be controlled without material remaining in the filling chamber, so that a material layer of consistent quality can be coated on the carrier.

[0039] In a preferred embodiment, the coating device comprises a drive unit connected to the material reservoir, in particular an electric drive unit, which is configured to drive the first relative movement of the filling chamber.

[0040] In another preferred embodiment, the coating device comprises a drive element connected to the material reservoir, wherein actuation of the drive element causes a relative movement of the filling chamber relative to the base body.

[0041] Execution here is to be understood as a mechanical interaction in which a force and / or a torque is transmitted to the drive element, thereby causing a relative movement of the filling chamber.

[0042] In this way, the coating device does not rely on an internal drive unit or similar device, but can be driven by the interaction of the drive element with other elements. This can reduce costs and maintenance work compared to designs with drive units.

[0043] In a preferred embodiment, the coating machine comprises a first contact element attached to the machine tool, in particular to the carrier, wherein the coating machine is configured to drive the interaction between the drive element and the first contact element by a movement of the base body, in particular by a first movement of the base body, thereby generating a first relative movement for emptying the filling chamber.

[0044] Thus, once the drive element interacts with the first contact element, the coating device for emptying the filling chamber is effectively activated by the coating machine's own movement. In this way, it is possible to dispense with an otherwise necessary drive unit in the coating machine, thereby reducing costs, installation space and maintenance effort.

[0045] Furthermore, the mechanical interaction is a reliable "limit switch" which always causes the filling chamber to be emptied at the same position during the movement of the base body and which is also safer against malfunctions than electronic limit switches.

[0046] Examples of the pairing of the drive element and the first contact element include the pairing of a contact disk and a rolling contact element (see Figure 1 ), the pairing of the gear plate and the rack (see Figure 2 ), eccentric crank and profile pairing (see Figure 3 ) or any type of pairing of sliders or grooved guides.

[0047] In a preferred embodiment, the coating machine includes a second contact element connected to the machine bed, wherein the coating machine is configured to drive the driving element by moving the base body to contact the second contact element, thereby generating a second relative movement of the filling chamber relative to the base body, so that the filling chamber is brought to an initial position suitable for refilling the material to be stored into the filling chamber.

[0048] In this way, the filling chamber realizes a completely automated movement step, which depends only on the movement of the base body of the coating machine.

[0049] In a preferred alternative embodiment, the coating machine includes a restoring element connected to the material reservoir, which applies a restoring force to the material reservoir to cause a second relative movement of the filling chamber relative to the base body, thereby bringing the filling chamber to an initial position suitable for refilling the material to be stored into the filling chamber.

[0050] In this way, after the first relative movement has occurred, the filling chamber can be restored to the initial position under the action of the restoring force, in particular when the drive element no longer interacts with the first contact element.

[0051] According to a second aspect of the present invention, there is provided a filling device for filling a material reservoir of a coating machine, the coating machine being configured to apply a plurality of material layers to a carrier of a machine tool so as to be movable relative to the carrier, the filling device comprising a supply reservoir having a storage chamber for storing material and an outlet for discharging the material stored in the storage chamber, and a dispensing device arranged on the supply reservoir, the dispensing device being configured to be brought from a first position in which the outlet is closed to a second position in which the outlet is open by the movement of the coating machine, so that the material stored in the storage chamber is filled into the material reservoir of the coating machine through the outlet. In particular, the machine tool is configured to produce a workpiece layer by layer from the material layers applied by the coating machine.

[0052] In this way, the movement of the coating machine itself becomes the trigger for filling or refilling the material reservoir, so there is no need for any electronic limit switches or similar devices, such as by a metering screw, which initiates filling when the coating machine reaches the refilling position below the outlet of the supply reservoir.

[0053] Furthermore, since the driving force required to operate the dispensing device is provided entirely by the coating machine itself, there is no need to directly drive relatively driven mechanical closing parts of the supply reservoir, for example by means of an electric motor.

[0054] The filling device is therefore designed as a passive, essentially stationary device connected to the machine tool and which serves to interact with the movable coating machine in order to fill the material reservoir through said interaction.

[0055] The outlet of the supply reservoir remains closed and does not interact with the coating machine, so that when the coating machine moves to other places, such as applying a layer of material, a larger amount of material can be supplied to the storage cavity of the supply reservoir for a subsequent filling process.

[0056] Preferably, the dispensing device comprises a restoring element which closes the outlet of the supply reservoir by exerting a restoring force when the applicator no longer interacts with the filling device, for example due to a loss of contact when the applicator is moved out of the filling position.

[0057] In a preferred embodiment, the dispensing device is designed as a sliding element, which is movably mounted relative to the supply reservoir and has a contact portion, which is designed to contact the coating machine during the movement of the coating machine and to move the sliding element from the first position to the second position as the movement proceeds.

[0058] In this way, a transmission-free interaction between the filling device or its dispensing device and the coating machine is achieved, with the dispensing device being activated by establishing contact at the contact part. Therefore, when installing the filling device on the machine, only the initial positioning of the contact part relative to the coating machine is required.

[0059] In order to be able to adapt to coating machines of different sizes, the sliding element preferably comprises an adjustment assembly, such as a pull-out assembly or the like, so that the position of the contact portion relative to the supply reservoir can be adjusted to the loading position of the coating machine.

[0060] As an alternative to a sliding element design, the dispensing device can also be designed as a tilting element, whose lever portion is designed to contact the coater when the coater moves and tilt the tilting element from a first position to a second position during the movement process (i.e., rotation around the support point of the tilting element).

[0061] In a preferred embodiment, the filling device further comprises a material reservoir and a dosing device, wherein the dosing device is configured to fill a predetermined amount of material from the material reservoir into the storage cavity of the supply reservoir.

[0062] This ensures that between the individual filling operations the storage chamber of the supply reservoir is always filled with the required amount of material for the coating machine.

[0063] In a preferred embodiment, the supply reservoir comprises an additional storage chamber for storing material and an additional outlet for discharging the material stored in the additional storage chamber, wherein the dispensing device is configured to also close the additional outlet in the first position and to also open the additional outlet in the second position.

[0064] In this way, the material reservoir of the coater is filled as the coater moves, and a greater amount of material can be applied to the carrier of the machine through the additional outlet, which is then spread on the carrier in a layer-by-layer manner as the coater moves out of the loading position.

[0065] Thus, a single movement of the coater on the feeding device can be well utilized in such a way that a first quantity of material is automatically applied to the carrier and a second quantity of material is filled into the material reservoir of the coater essentially at the same time, wherein the first quantity of material applies a first material layer and then a second material layer is applied to the carrier based on the material stored in the material reservoir.

[0066] According to a third aspect of the invention, there is provided a system for coating a carrier of a machine tool with a plurality of material layers. The machine tool is configured to produce a workpiece layer by layer from the coated material layers and comprises a coating machine according to an embodiment of the first aspect of the invention and a filling device according to an embodiment of the second aspect of the invention, the filling device being configured to fill a material reservoir of the coating machine.

[0067] In this way, a system for depositing material layers by additive manufacturing is provided, which combines the above-mentioned advantages of the coating machine according to the first aspect and the filling device according to the second aspect.

[0068] Particularly in the embodiment of the coating machine with drive elements, almost all actions for moving the material to be coated are triggered or performed by the movement of the carrier of the coating machine relative to the machine bed.

[0069] Thus, the system according to the third aspect exemplarily demonstrates that no electronic limit switches are required to coordinate the movements of the individual components, thereby achieving a simple and fully mechanized synchronization of the carrier, the coater and the filling device, which is both safe against failures and cost-effective with low maintenance requirements.

[0070] According to a fourth aspect of the present invention, there is provided a method for additively manufacturing a workpiece using a machine tool, the machine tool comprising at least a carrier and a coating machine for coating a plurality of material layers on the carrier. In this case, the method comprises at least the following steps: coating a certain amount of material stored in a filling chamber of a material reservoir of the coating machine onto the carrier of the machine tool; spreading a certain amount of material applied from the filling chamber in a layer-forming manner by the coating machine, thereby coating the material layer onto the carrier; and forming a workpiece layer of the workpiece by melting or sintering a portion of the coated material layer, wherein coating a certain amount of material stored in the filling chamber of the material reservoir of the coating machine onto the carrier of the machine tool comprises moving the filling chamber relative to a base body of the coating machine carrying the material reservoir to empty the filling chamber.

[0071] Thus, this additive manufacturing process exploits the advantages of uniform, rapid and reliable application of material layers, which has been described in the coating machine associated with the present invention.

[0072] This enables efficient additive manufacturing of workpieces with low downtimes and high manufacturing quality.

[0073] The material layer should usually be applied evenly from a predetermined amount of material. However, due to irregular and sometimes incomplete application by a closing mechanism, for example, the amount of applied material may fluctuate, so that the material layer may not be completely applied because too little material is applied. In the case of a closing mechanism, in order to compensate for this problem, an overdose of application material exceeding the predetermined amount is usually used.

[0074] On the other hand, when using the coating machine of the present invention, since the relative movement of the filling chamber can completely empty the material stored therein, overfilling is no longer necessary, so that material can be saved during the coating of the material layer.

[0075] Likewise, according to the coating machine of the present invention, the mechanical parts of the coating machine are only slightly loaded by the material to be coated, so when the coating machine is used by additive manufacturing, the inaccuracy caused by wear when coating the material layer can be reduced and the service life can be extended.

[0076] Preferably, the layer of material is applied to the carrier by spreading the amount of material applied from the filling chamber in a layer-forming manner by a coater, comprising moving a base body of the coater relative to the carrier of the machine bed.

[0077] Preferably, before using the amount of material stored in the filling chamber of the material reservoir, the method comprises applying a first amount of material to a carrier of the machine tool and filling the filling chamber of the material reservoir of the coating machine with the amount of material to be stored in the filling chamber.

[0078] In this way, the required amount of material for two consecutive material layers can be provided together at one feeding position of the coating machine.

[0079] Preferably, the method also includes applying a first material layer on the carrier by spreading a first amount of material applied to the carrier in a layer-forming manner, in particular during a first movement of the base body relative to the carrier, and forming a first workpiece layer of the workpiece by melting or sintering a portion of the material of the applied first material layer.

[0080] In this way, while the first material layer is applied by the coater, the material required for the subsequent application of the material layer spread out from the material stored in the filling chamber can also be carried along. This reduces the number of strokes and thus the production time. When the coater reaches the end position and has applied the first layer of material, the first workpiece layer can be formed immediately without having to move the coater back to the starting position beforehand.

[0081] After the first workpiece layer has been deposited, the stored material is discharged from the filling chamber and the above-mentioned process steps are then carried out.

[0082] However, in order to further reduce the processing time during production, it is advantageous if the stored material can also be applied while the first workpiece layer is being deposited.

[0083] Further aspects and advantages of the above-mentioned aspects and features as well as more specific embodiments will be described below with the aid of the accompanying drawings.

[0084] Figure 1 A to 1C are schematic cross-sectional views showing different positions of the first embodiment of the coating machine according to the present invention during the movement of the base body.

[0085] Figure 2 A schematic cross-sectional view of a second embodiment of a coating machine according to the invention is shown.

[0086] Figure 3 A to Figure 3 C shows a cross-sectional perspective view of the third embodiment of the coating machine according to the present invention at different positions during the movement of the base body.

[0087] Figure 4 4A and 4B show schematic diagrams of a fourth embodiment of a coating machine according to the present invention.

[0088] Figure 5 5A and 5B are schematic diagrams showing a machine tool with a coating machine and a filling device according to an embodiment of the present invention in different states.

[0089] Figure 6 A flow chart of a method for additive manufacturing of a workpiece according to an embodiment of the present invention is shown.

[0090] It should be emphasized that the present invention is by no means limited to the following embodiments and their features. The present invention also includes modifications to the embodiments, in particular modifications and / or combinations of single or multiple features of the embodiments within the scope of protection of the independent claims. DETAILED DESCRIPTION

[0091] Figure 1 A to 1C are cross-sectional schematic diagrams showing different positions of the base body 11 of the coating machine 10 according to the first embodiment of the present invention during the movement of the base body 11 of the coating machine 10 .

[0092] The coating machine 10 shown in the figure includes a base body 11 and a material storage device 12. The material storage device 12 is supported by the base body 11 and is used to apply the material 1 coated by the coating machine 10 to a carrier 31 of a machine tool in the form of a material layer, so as to form a workpiece layer of the workpiece on the carrier 31 by additive manufacturing.

[0093] In the embodiment shown, the carrier 31 is plate-shaped, on the basis of which the base body 11 of the coating machine 10 is movable relative to the carrier 31 of the machine tool.

[0094] In the illustrated embodiment, the base body 11 is translatably movable back and forth between a first end position and a second end position along the illustrated x-direction relative to the carrier 31 , so that the x-direction is parallel to the surface of the plate-shaped carrier 31 .

[0095] The lower side of the coating machine 10 includes a spreading element 19 toward the carrier 31, which element can be designed, for example, as a coating brush, a coating lip or a coating knife, for spreading the material 1 located on the carrier 31 layer by layer during the movement of the base body 11 between the first end and the second end position (or vice versa).

[0096] In the embodiment shown, the material reservoir 12 is cylindrical and comprises a filling chamber 13 having a semicircular cross section and a filling chamber 14 having a semicircular cross section and a filling chamber 15 having a semicircular cross section and a filling chamber 16 having a semicircular cross section and a filling chamber 17 having a semicircular cross section and a filling chamber 18 having a semicircular cross section and a filling chamber 19 having a semicircular cross section and a filling chamber 11 having a semicircular cross section and Figure 1 A) an opening at the top, through which the material 1 to be stored can be filled into the filling chamber 13 of the material storage 12. The material storage 12 with the filling chamber 13 can store the material 1 and carry it during the movement of the base body 11.

[0097] In this way, during the first movement from the first end position to the second end position along the X-axis direction, and while the first quantity of material 1 is spread on the carrier 31 to form a first layer through the spreading element 19, the second quantity of material 1 can be carried for spreading the second layer, that is, in the subsequent second movement, back from the second end position to the first end position against the X-direction.

[0098] When the base body 11 reaches its end position relative to the carrier 31 at the end of the first movement, the coating machine 10 is configured to coat the amount of material 1 stored in the filling chamber 13 onto the carrier 31, such as Figure 1 A to 1C are shown in chronological order.

[0099] To this end, the coating machine 10 comprises a coating device which, in this case, comprises a support for a rotatable material reservoir 12 whose filling chamber 13 is emptied by a rotational relative movement of the filling chamber 13 relative to the base body 11 (about the rotation axis R).

[0100] In order to initiate the rotational relative movement, the coating device comprises a drive element which is connected to the material reservoir 12 and is designed in the present example as a semicircular contact disk 15 a.

[0101] The shape of the contact disk 15a is not limited to a semicircle, and can be designed as any part of a circle or a complete circle in the cross section shown. The rotation of the contact disk 15a is thus transmitted to the material storage 12, and drives the rotational relative movement of the filling chamber 13.

[0102] The coating machine 10 further comprises a first contact element connected to the carrier 31, in this case designed as a rolling contact element 16a. The coating machine 10 is thus configured in such a way that when the base body 11 moves in the x direction, the contact disc 15a interacts with the rolling contact element 16a, thereby generating a rotational relative movement for emptying the filling chamber 13.

[0103] from Figure 1 Starting from the position in A, as the base body moves, the contact plate 15a contacts the rolling contact element 16a (see Figure 1B), as a result, the contact disc 15a rolls on the rolling contact element, the rotation of the contact disc 15a is transmitted to the material reservoir 12 and its filling chamber 13, and then the filling chamber 13 starts to rotate from its initial position relative to the base body 11 according to the rolling of the contact disc 15a.

[0104] The rotation causes the filling chamber 13, especially the position of its opening relative to the base body 11 to change, and the powdered material 1 thus begins to flow relative to the filling chamber 13 as it rotates, and moves toward the opening of the filling chamber 13, thereby passing through and reaching the carrier 31. Figure 1 The position shown in C ends, when the filling chamber 13 is completely emptied.

[0105] The powdered material 1 does not come into contact with mechanical parts of the coating machine 10 (such as bearing points, guide joints, etc.), thereby reducing wear and extending the service life.

[0106] Likewise, the mobile filling chamber 13 itself ends, exemplarily, at Figure 1 The upper position of the filling chamber 13 shown in C ensures that it is completely emptied without any residual material remaining therein.

[0107] like Figure 1 C, a quantity of material 1 has been applied to the carrier from the filling chamber 13 of the material reservoir and can be spread in a layer-by-layer manner on the carrier 31 by the spreading element 19 in a second movement of the base body 11 against the X direction.

[0108] Furthermore, the coating machine 10 further comprises a channel 14 located on the left side of the cross section shown, which extends from the upper side of the base body 11 to the lower side facing the carrier 31. The channel 14 is used to directly convey the material 1 onto the carrier 31 in interaction with a filling device (not shown). The filling device is used to fill the material into the filling chamber 13 of the material reservoir 12 and to apply the material directly onto the carrier 31 through the channel 14, in particular in order to spread onto the carrier 31 in a layer-forming manner during the first movement, while carrying a larger amount of material 1 in the filling chamber 13.

[0109] Figure 2 A schematic cross-sectional view of a second embodiment of a coating machine according to the present invention is shown.

[0110] In addition to the design of the drive element and the first contact element of the coating device, the design of the coating machine 10 is similar to Figure 1 A to Figure 1 The first embodiment in C corresponds to the first embodiment, so it will not be repeated here.

[0111] The drive element in the second embodiment is designed as a gear wheel 15b, which interacts as a first contact element with a toothed rack 16b connected to the carrier 31, so as to cause the filling chamber 13 to undergo a rotational relative movement via a toothed mechanism.

[0112] and Figure 1 Compared to the version with contact disc 15a and rolling contact element 16a, this version is more expensive, but there are no slipping problems when rolling contact disc 15a, so the rotational relative movement can be better controlled.

[0113] In the first and second embodiments, the first contact element (rolling contact element 16a or rack 16b) is also the second contact element, which interacts with the driving element (contact disk 15a or gear 15b) during the second movement of the base body 11 so as to return the filling chamber 13 to its initial position through a second relative movement, thereby allowing the filling chamber 13 to be filled with the material 1 to be stored again.

[0114] Figure 3 A to Figure 3 C shows another possibility of starting the relative movement of the filling chamber 13, Figure 3 A to Figure 3 C shows a cross-sectional perspective view of the third embodiment of the coating machine 10 according to the present invention at different positions during the movement of the base body 11 .

[0115] The coating machine 10 shown comprises a base body 11 (only partially shown) and a material storage device 12 carried by the base body 11 for storing material to be coated in the form of a material layer by the coating machine 10 onto a machine tool carrier (not shown here) so as to produce a workpiece layer of the workpiece by an additive manufacturing method.

[0116] The base body 11 of the coating machine 10 can be moved relative to the carrier of the machine tool. In the example shown, the base body 11 can be translated back and forth along the x-direction shown.

[0117] In the illustrated embodiment, the material reservoir 12 is cylindrical and includes a groove-shaped recess combined with the cylindrical geometry as an opening of a filling chamber 13 on one side of the cylindrical wall, through which the material to be stored can be filled into the filling chamber 13 of the material reservoir 12.

[0118] The coating machine 10 comprises a coating device arranged transversely to a material reservoir 12 , which comprises a rotatable mount of the material reservoir 12 relative to the illustrated part of a base body 11 .

[0119] For example, the support can be designed as a roller bearing or a sliding bearing. The coating device is configured to rotate the filling chamber 13 relative to the base body 11 around the rotation axis R (refer to Figure 3 A and Figure 3 B) to empty the filling chamber 13 of the material storage 12.

[0120] In order to initiate the rotational relative movement, the coating device comprises a drive element connected to the material reservoir 12, which is designed as an eccentric crank 15c. The eccentric crank 15c comprises a pin eccentrically positioned relative to the rotation axis R of the material reservoir 12, which is configured to interact with contact elements 16c, 16d on the side of the machine tool to drive the rotational relative movement of the filling chamber 13.

[0121] To this end, the coating machine 10 includes a first contact element connected to the machine tool, which is designed as a contour body 16c with an arc-shaped guide surface. During the first movement along the x-axis direction, the pin of the eccentric crank 15c that contacts the contour body 16c is guided by the guide surface of the contour body 16c (see Figure 1 B), thereby driving the eccentric crank 15c to rotate, the rotation is transmitted to the material reservoir 12, and causes a relative movement to empty the filling chamber 13.

[0122] Upon reaching the end position (see Figure 3 C), the emptied filling chamber 12 can return to the initial position by interacting with the second contact element on the machine tool. Similar to the first contact element, the second contact element is also designed as a second contour body 16d with an arc-shaped guide surface. During the second movement in the direction opposite to the x-axis, the pin of the eccentric crank 15c that contacts the second contour body 16d is guided by the guide surface of the second contour body 16d, thereby driving the eccentric crank 15c to rotate, and the rotation is transmitted to the material storage 12, and the filling chamber 13 is brought back to the initial position.

[0123] Figure 4 4A and 4B show perspective views of a fourth embodiment of a coating machine according to the present invention ( Figure 4 A) and enlarged cross-sectional view ( Figure 4 B).

[0124] The coating machine 10 shown in the figure includes a frame-shaped base body 11, in which a material storage device 12 is installed in the first groove of the base body 11 for storing the material that the coating machine 10 will coat in the form of a material layer onto a carrier of a machine tool (not shown here), so as to produce a workpiece layer of a workpiece on the carrier by an additive manufacturing method.

[0125] The base body 11 of the coating machine 10 can be moved relative to the carrier of the machine tool. In the example shown, the base body 11 can be translated back and forth along the x-direction shown.

[0126] The underside of the coating machine comprises a spreading element 19 located towards the carrier, which element is designed as a coating lip in the present example for spreading a quantity of material 1 located on the carrier in a layer-forming manner during the movement of the base body 11 .

[0127] In the exemplary embodiment shown, the material reservoir 12 is designed as a grooved shaft, whose groove-shaped recess serves as a filling chamber 13 for the material.

[0128] The coating machine 10 comprises a coating device which comprises a rotatable mounting of material reservoirs 12 relative to a base body 11 , each material reservoir 12 having a transverse bearing point 17 . Figure 4 B shows Figure 4 A is an enlarged sectional view in the region of the front end support point 17, showing the rotatable support by means of a ball bearing.

[0129] The coating apparatus is configured to empty the filling chamber 13 of the material reservoir 12 by a rotational relative movement of the filling chamber 13 relative to the base body 11 about the rotational axis R.

[0130] In order to initiate the rotational relative movement, the coating device comprises a drive element connected to the material reservoir 12, which is designed in this case as an eccentric crank 15c and Figure 3 The embodiments shown are similar.

[0131] The eccentric crank 15c comprises a pin which is eccentrically positioned relative to the rotation axis R of the material reservoir 12 and which is configured to interact with a contact element (not shown here) on the side of the machine tool to bring about a rotational relative movement of the filling chamber 13 (see also Figure 3 A to Figure 3 C). The eccentric crank 15c is fixed to one end face of the material storage 12 by means of screws. The material storage 12 is designed as a grooved shaft, so that the rotation of the eccentric crank 15c can be transmitted to the grooved shaft.

[0132] In addition, the coating machine includes an elastic restoring element 18 designed as a helical spring, which is connected to the material reservoir 12 via an eccentric crank 15c. The connection point is eccentric to the rotation axis R, so that the restoring force applied by the restoring element 18 applies a restoring torque to the material reservoir 12 to return it to the initial position suitable for filling the filling chamber 13 (corresponding to Figure 4 position shown in A).

[0133] Figure 5 5A and 5B show schematic views of a machine tool 30 with a coating machine 10 and an exemplary embodiment of a filling device 20 according to the invention in different states.

[0134] Figure 5 A shows the coating machine 10 in the filling position, while Figure 5B shows the coating machine 10 in the end position opposite to the filling position.

[0135] The machine tool comprises a carrier 31 , a processing device 32 for optically irradiating a material layer on the carrier with a laser beam 33 , and a housing 34 defining a processing space of the machine tool 30 .

[0136] Furthermore, the machine tool 30 comprises a coating machine 10 and a filling device 20 for filling a material reservoir 12 of the coating machine 10 .

[0137] Figure 5 The coating machine 10 shown in A and 5B can be a coating machine designed according to the first aspect of the present invention, but is not limited thereto, as long as the coating machine 10 includes a material storage device 12, which has a filling chamber that can be filled by a filling device 20 so that the material 1 stored therein can be transported away during the movement of the coating machine 10 (in this case, translation in direction T).

[0138] The coating machine 10 comprises a channel 14 for transferring the material 1 from the upper opening directly to the lower opening facing the carrier 31 .

[0139] The filling device 20 comprises a supply reservoir 21 with a storage chamber 22 for storing the material 1, an outlet 22a for discharging the material 1 stored in the storage chamber 22, and a dispensing device arranged on the supply reservoir 21, which is designed as a sliding element 24, which can be moved by the coating machine 10 from a first position in which the outlet 22a is closed (see Figure 5 B) moves to the second position where the outlet 22a is opened (see Figure 5 A), thus, the material 1 stored in the storage chamber 22 is filled into the material storage 12 of the coating machine 10 through the outlet 22a.

[0140] The sliding element 24 has a contact portion 24a orthogonal to the moving direction T, and its purpose is to contact the contact portion 24a during the movement of the coating machine 10 and move the sliding element 24 from the first position to the second position during the movement. In this case, when the coating machine 10 moves from left to right, the outlet 22a is opened during this process.

[0141] Thus, when the coating machine 10 moves to the feeding position (see Figure 5 A), the material reservoir 12 can be filled without an additional drive unit or the like, simply by causing the coating machine 10 itself to displace a sliding element 24 which is mounted on the underside of the supply reservoir 21 so as to be movable parallel to the displacement direction T.

[0142] The filling device 20 is thus arranged as a passive and substantially stationary device mounted on the machine bed 30 for interacting with the mobile coating machine 10 , by means of which interaction the material reservoir 12 thereof is filled.

[0143] Furthermore, the filling device 20 comprises an additional storage chamber 23 with an associated additional outlet 23a, which can also be opened or closed by a sliding element 24, preferably together with the further outlet 22a.

[0144] The material 1 discharged through the additional outlet 23a falls directly onto the carrier 31 through the channel 14 of the coating machine 10 and Figure 5 The feeding position shown in A is Figure 5 The end position shown in B spreads out in a layered manner during the movement.

[0145] In addition, the filling device 20 also includes a dosing device 26, which is arranged at the top opening of the supply storage container 21 and is designed as a rotary valve in this case. After the coating machine 10 drives the sliding element 24 to empty the storage chamber 22 and the additional storage chamber 23, the material 1 can be injected into the storage chamber 22 and the additional storage chamber 23 from the material reservoir 25 through the dosing device 26.

[0146] In this way, a further filling of the material reservoir 12 can take place or material can be discharged through the channel 14 of the coating machine 10 onto the carrier 31 .

[0147] Figure 6 A flow chart of an exemplary embodiment of a method according to the invention is shown, the method having steps S1 to S7 for additive manufacturing of a workpiece using a machine tool, the machine tool comprising at least a carrier and a coating machine for applying a material layer to the carrier.

[0148] In step S1 , a first amount of material is applied to a carrier of a machine tool.

[0149] In step S2 , a second amount of material is filled into a filling chamber of a material reservoir of the coating machine.

[0150] In step S3 , a layer of material is applied to the carrier by spreading a first amount of material in a layer onto the carrier, in particular in a first movement of a base body of the coating machine relative to the carrier.

[0151] In step S4 , a part of the applied material layer is formed into a workpiece layer of the workpiece to be produced by melting or sintering, in particular by means of a laser processing device of a machine tool.

[0152] In step S5 , the second amount of material stored in the filling chamber is applied to the carrier of the machine tool by moving the filling chamber relative to the base body of the coating machine in such a way as to empty the filling chamber.

[0153] In step S6 , a next layer of material is applied to the carrier by spreading a second amount of material in a layer-forming manner onto the carrier, in particular in a second movement of the coating machine relative to the carrier.

[0154] In step S7 , a part of the applied next material layer is melted or sintered, in particular by means of a laser processing device of a machine tool, so as to form the next workpiece layer of the workpiece to be produced.

[0155] Subsequently, steps S1 to S7 are repeated as many times as necessary to form a large number of workpiece layers until the desired workpiece is produced. Description of reference numerals: 1 Materials 10 Coating machine 11 Base body 12 Material Storage 13 Filling chamber 14 channels 15a Contact plate 15b Gear 15c eccentric crank 16a Rolling contact element 16b Rack 16c Contour Body 16d Second contour 17 Support point 18 Recovery Components 19 Spreading Elements 20 Filling device 21 Supply Storage 22 Storage chamber 22a Exit 23 Additional storage chamber 23a Additional exit 24 Sliding elements 24a Contact part 25 Material storage 26 Batching device 30 Machine Tools 31 Carrier 32 Processing equipment 33 Laser Beam 34 Shell

Claims

1. A coating machine (10) for coating a plurality of material layers onto a carrier (31) of a machine tool (30), wherein the coating machine (10) is configured to produce a workpiece layer by layer from the coated material layers, comprising: A base body (11) movable relative to the carrier (31) of the machine tool (30); A material storage container (12) supported by the base body (11), wherein the material storage container (12) has a filling chamber (13) for storing the material (1); It is characterized by that it also includes A coating device is configured to empty the filling chamber (13) of the material reservoir (12) by a first relative movement of the filling chamber (13) relative to the base body (11) so as to coat the material (1) stored in the filling chamber (13) onto the carrier (31).

2. The coating machine (10) according to claim 1, characterized in that: The coating device comprises a rotatable support, by which the material reservoir (12) is supported so that the material reservoir (12) can rotate relative to the base body (11) around a rotation axis (R), so that the first relative movement for emptying the filling chamber (13) is a rotation around the rotation axis (R).

3. The coating machine (10) according to claim 1 or 2, characterized in that: The coating machine (10) comprises a spreading element (19) connected to the base body (11), and the spreading element (19) is configured to spread a certain amount of material placed on the carrier (31) in a layer-forming manner through the movement of the base body.

4. The coating machine (10) according to claim 3, characterized in that: The base body (11) is movable relative to the carrier (31) between a first end position and a second end position. wherein the coating machine (10) is configured to spread a first quantity of material (1) on the carrier (31) in a layer-forming manner using the spreading element (19) by a first movement of the base body (11) from the first end position to the second end position, while carrying a second quantity of material (1) in the material reservoir (12), and is further configured to empty the filling chamber (13) of the material reservoir (12) by the first relative movement so as to apply the second amount of material (1) to the carrier (31) when the second end position or a coating position between the first end position and the second end position is reached.

5. The coating machine according to claim 4, characterized in that: The coating machine (10) is configured to spread the second amount of material (1) applied to the carrier (31) in a layer-forming manner on the carrier (31) by a second movement of the spreading element (19) from the second end position to the first end position through the base body (11). The second amount of material (1) applied to the carrier (31) when the second end position or the coating position is reached.

6. The coating machine (10) according to any one of the preceding claims, characterized in that The coating device comprises a drive unit connected to the material reservoir (12), the drive unit being configured to cause the first relative movement of the filling chamber (13) relative to the base body (11).

7. The coating machine (10) according to any one of claims 1 to 5, characterized in that The coating device comprises a drive element (15a; 15b; 15c) connected to the material reservoir (12), wherein actuation of the drive element causes a relative movement of the filling chamber (13) relative to the base body (11).

8. The coating machine (10) according to claim 7, characterized in that The coating machine (10) comprises a first contact element (16a; 16b; 16c) attached to the machine bed (30), The coating machine (10) is configured to drive the interaction between the driving element (15a; 15b; 15c) and the first contact element (16a; 16b; 16c) by the movement of the base body (11), thereby generating the first relative movement for emptying the filling chamber (13).

9. A coating machine (10) according to claims 7 to 8, characterized in that The coating machine (10) comprises a second contact element (16d) attached to the machine bed (30), The coating machine (10) is configured to drive the driving element (15a; 15b; 15c) by moving the base body (11) to contact the second contact element (16d) to cause a second relative movement of the filling chamber (13) relative to the base body (11), so that the filling chamber (13) is brought to an initial position suitable for refilling the material (1) to be stored into the filling chamber (13).

10. The coating machine (10) according to any one of claims 1 to 8, characterized in that The coating machine (10) includes a recovery element connected to the material reservoir (12), and the recovery element applies a restoring force to the material reservoir (12) to cause a second relative movement of the filling chamber (13) relative to the base body (11), so that the filling chamber (13) is brought to an initial position suitable for refilling the material (1) to be stored into the filling chamber (13).

11. A filling device (20) for filling a material reservoir (12) of a coating machine (10), the coating machine (10) being configured to apply a plurality of material layers to a carrier (31) of a machine bed (30), and the coating machine (10) being movable relative to the carrier (31) in the carrier (31), the filling device (20) comprising: a supply storage device (21) having a storage chamber (22) for storing a material and an outlet (22a) for discharging the material (1) stored in the storage chamber (22); It is characterized by that it also includes A dispensing device (24) is arranged on the supply storage (21), and is configured to be brought from a first position where the outlet (22a) is closed to a second position where the outlet (22a) is opened through the movement of the coating machine (10), so that the material (1) stored in the storage chamber (22) is filled into the material storage (12) of the coating machine (10) through the outlet (22a).

12. The filling device according to claim 11, characterized in that The dispensing device is designed as a sliding element (24), which is movably mounted relative to the supply reservoir (21), and the sliding element (24) has a contact portion (24a), which is designed to contact the coating machine (10) during the movement of the coating machine (10) and to move the sliding element (24) from the first position to the second position as the movement proceeds.

13. The filling device according to any one of claims 11 to 12, characterized in that The filling device (20) further comprises a material reservoir (25) and a dosing device (26), wherein the dosing device (26) is configured to fill a predetermined amount of material (1) from the material reservoir (25) into the storage cavity (22) of the supply reservoir (21).

14. The filling device according to any one of claims 11 to 13, characterized in that The supply storage (21) comprises an additional storage chamber (23) for storing the material (1) and an additional outlet (23a) for discharging the material (1) stored in the additional storage chamber (23), The dispensing device (24) is configured to close the additional outlet (23a) in the first position and to open the additional outlet (23a) in the second position.

15. A system for coating a carrier (31) of a machine tool (30) with a plurality of material layers, the system being configured to manufacture a workpiece layer by layer by means of the coated plurality of material layers, comprising: A coating machine (10) according to any one of claims 1 to 10; as well as A filling device according to any one of claims 11 to 14, for filling the material reservoir (12) of the coating machine (10).

16. A method for additive manufacturing of a workpiece using a machine tool (30), the machine tool (30) comprising at least one carrier (31) and a coating machine (10) for coating a plurality of material layers on the carrier (31), the method comprising at least the following steps: Applying a certain amount of material (1) stored in a filling chamber (13) of a material storage device (12) of the coating machine (10) onto the carrier (31) of the machine tool (30); spreading a quantity of material (1) applied from the filling chamber (13) in a layer-forming manner using the coating machine, thereby coating the material layer on the carrier (31); Forming a part of the applied material layer into a workpiece layer of the workpiece by melting or sintering; It is characterized in that Applying the quantity of material (1) stored in the filling chamber (13) of the material reservoir (12) of the coating machine (10) onto the carrier (31) comprises: The filling chamber (13) is moved relative to a base body (11) of the coating machine (10) carrying the material reservoir (12) in order to empty the filling chamber (13).

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