Description:
The following specification particularly describes the invention and the manner in which it is to be performed.
TECHNICAL FIELD

Present disclosure relates in general to a field of manufacturing technology. Particularly, but not exclusively, the present disclosure relates to an additive manufacturing process. Further embodiments of the present disclosure discloses an attachment device for improving surface finish of walls produced using wire arc additive manufacturing process.

BACKGROUND

Additive manufacturing is a process used to fabricate 3-dimensional (3D) parts or products by adding layer-upon-layer of material. Additive manufacturing utilizes 3D-modeling (Computer-Aided Design or CAD) software, computer-controlled additive-manufacturing equipment, and raw materials in powder or semi-molten form to build the required product. This process encompasses a wide variety of technologies and incorporates a wide variety of techniques, such as, for example, laser freeform manufacturing (LFM), laser deposition (LD), direct metal deposition (DMD), laser metal deposition, laser additive manufacturing, laser engineered net shaping (LENS), stereolithography (SLA), fused deposition modeling (FDM), 3D printing, rapid prototyping, layered manufacturing, and additive fabrication. Moreover, a variety of raw materials may be used in additive manufacturing to create products. Examples of such materials include plastics, metals, concrete, and glass.

One example of an additive-manufacturing system is a wire arc-based additive manufacturing (WAAM) technique that involves utilizing an electric arc as a heat source in combination with a metallic wire as the feed source. A power source is used to create the electric arc which extends from an electrode to the base material. The arc quickly heats and melts the metallic wire at the base material. Similarly, yet another process such as Gas Tungsten Arc Welding (GTAW) utilizes metallic wires that is fed into a pool of molten metal created when an electrical arc extends from a tip of the tungsten electrode to the base material forming the molten pool of metal. The melted wire is then used to add material in the form of layers to the base material.

However, articles or products formed by additive manufacturing may require some finishing processes such as surface processing to convert it into a final product. Primary reason being that, since the processes includes molten metal, the surface accuracy or finish of such articles is not perfect, as there exists surface defects. One example of surface processing includes smoothing or otherwise reducing roughness on the surface of the product. Surfaces produced by additive manufacturing may have rough surface finishes, e.g., on the order of about 600-1000 microinches. Such rough surfaces may have several undesirable effects. For example, parts having a rough surface finish have limited applications in cyclical-loading environments due to stress risers typically associated with high surface roughness. Additionally, rough surfaces may impede the use of cost-saving, non-destructive inspection systems because rough surface finishes generate high levels of noise in such systems.

More specifically, some products or components like thin-walled structures maybe produced through WAAM technique which also requires post processing like machining or surface grinding, as poor surface finish is one of the limitations of the process. To improve the surface finish of a part fabricated with additive-manufacturing equipment, separate post-processing steps must be undertaken at processing location using conventional surface-finishing equipment and techniques. However, due to the complexity of some parts, post-processing of surfaces thereof may be cumbersome, expensive, and time consuming. In addition, conventional post-processing surface-finishing methods may be ineffective for reducing the surface roughness of the interior surfaces of some complex parts, resulting in products with less than desirable properties. Further to the above, the molten metal buckles under its own weight during the deposition of material until it solidifies. Hence, there is a need for a device and system to overcome at least one of the problems mentioned above.

The present disclosure is directed to overcome one or more limitations stated above or other such limitations associated with the conventional systems.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the conventional method and system are overcome by the method and the system as claimed and additional advantages are provided through the provision of the system as claimed in the present disclosure.

Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one non-limiting embodiment of the disclosure, a device for supporting material deposited by an additive manufacturing machine is disclosed. The device includes a support bracket removably attached to a deposition head of the additive manufacturing machine. At least one connecting rod is provided in the device, such that it extends from the support bracket on either side of the deposition head towards a tip of the deposition head. Further, the device includes a guiding member supported by each of the at least one connecting rod wherein, opposing sides of each of the guiding member defines a space to receive and support the material deposited by the additive manufacturing machine.

In an embodiment of the disclosure, the device includes an adjusting mechanism. The mechanism is provided between the at least one connecting rod extending from either side of the deposition head, wherein the adjusting mechanism is configured to adjust the space between the guiding members.

In an embodiment of the disclosure, each of the at least one connecting rod is connected to the support bracket through a plurality of fasteners.

In an embodiment of the disclosure, the guiding member is connected to each of the at least one connecting rod through the plurality of fasteners.

In an embodiment of the disclosure, the guiding member is made of a thermally conductive material to dissipate heat generated during deposition of the material.

In an embodiment of the disclosure, the additive manufacturing machine is a wire arc additive manufacturing machine.

In another non-limiting embodiment of the disclosure, an additive manufacturing machine is disclosed. The machine includes a robotic arm, a deposition head coupled to the robotic arm, wherein the robotic arm is communicatively coupled to a control unit. The control unit is further configured to operate the robotic arm to traverse the deposition head in a predetermined pattern for depositing a material on a base. A device supporting the material deposited by the deposition head is disclosed. The device includes a support bracket removably attached to the deposition head. At least one connecting rod is provided such that it extends from the support bracket on either sides of the deposition head towards a tip of the deposition head. A guiding member is supported by each of the at least one connecting rod, wherein, opposing sides of each of the guiding member defines a space to receive and support the material deposited by the additive manufacturing machine.

It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiments of the disclosure.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

FIG.1 schematic representation of a wire arc additive manufacturing machine, in accordance with an embodiment of the present disclosure.

FIG.2 illustrates a perspective view of an attachment device for supporting material deposited by the wire arc additive manufacturing machine, in accordance with an embodiment of the present disclosure.

FIG.3 illustrates a side view of the attachment device of FIG 2.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the system and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure.

It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other systems for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent processes do not depart from the scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.

Embodiments of the present disclosure describe a device for supporting material deposited by an additive manufacturing machine. Conventionally, to improve the surface finish of a part fabricated with additive-manufacturing machine, separate post-processing steps must be undertaken at processing location using conventional surface-finishing equipments and techniques. However, due to the complexity of some parts, post-processing of surfaces thereof may be cumbersome, expensive, and time consuming. In addition, conventional post-processing surface-finishing methods may be ineffective for reducing the surface roughness of the interior surfaces of some complex parts, resulting in products with less than desirable properties.

Accordingly, a device and system for supporting material deposited by an additive manufacturing machine is disclosed. The device of the present disclosure includes a support bracket, connecting rod, adjusting mechanism, and guiding members. The device is attached to the deposition head of the additive manufacturing machine with the help of support brackets. Further, a plurality of connecting rods are provided which extends on either sides of the deposition head towards the tip of the deposition head. The guiding members are provided such that they are supported by the plurality of connecting rods. The opposing sides of each of the guiding member defines a space to receive and support the material deposited by the additive manufacturing machine. In some embodiment, the opposing surface of the guide members may be profiled in predetermined shape, relative to the shape and configuration of the structure/article to be manufactured by the additive manufacturing process. The device further includes an adjusting mechanism which is provided in between the at least one connecting rod that extends from either sides of the deposition head. The adjusting mechanism is configured to adjust the space between the guiding members. Presently there is no device available as an attachment device for supporting material deposited by an additive manufacturing process which can improve the surface finish of the walls.

The terms “comprises”, “comprising”, or any other variations thereof used in the specification, are intended to cover a non-exclusive inclusion, such that a system that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or method. In other words, one or more elements in an assembly proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the assembly.

Henceforth, the present disclosure is explained with the help of one or more figures of exemplary embodiments. However, such exemplary embodiments should not be construed as limitation of the present disclosure. One skilled in the art would appreciate that this device may be employed in any manufacturing process including but not limiting to laser additive manufacturing, welding, soldering, casting, and the like.

The following paragraphs describe the present disclosure with reference to Figs.1 to 3. In the figures, the same element or elements which have similar functions are indicated by the same reference signs.

FIG.1 is an exemplary embodiment of the present disclosure, representing a schematic of a wire arc additive manufacturing machine (WAAM). As represented in FIG.1, the wire arc additive manufacturing machine comprises a deposition head (102), a feeder unit (200), a robotic arm (204), a base (206), and a power source [not shown in figure]. The power source may be connectable to a power outlet as standard. However, the same shall not be considered as a limitation as any other form of power such as portable power or grid power may be used. The feeder unit (202) is connected to the deposition head (102) which is provided at the end of the robotic arm (204). The feeder unit (202) may be mounted to a base of the WAAM which is configured to provide the feeder material (114) to the deposition head (102) from a material reservoir [not shown]. The feeder unit (202) may supply or feed metallic wires such as but not limited to aluminium, alloys of titanium, etc., as raw material to the deposition head (102). The deposition head (102) that is coupled to the end of the robotic arm (204) may traverse with the robotic arm (204) and may act as an intermediate material transfer member between a heating unit and the feeder unit (202). The robotic arm (204) is configured with an actuator to position the deposition head (102) at the deposition zone. The robotic arm (204) may further include a plurality of linkages and may be operable in a pre-determined three-dimensional space. In some embodiments, the robotic arm (204) may be a 6-axis robot that is maneuverable in X, Y and Z planes. The robotic arm (204) may include multiple actuators for facilitating the movement of the robotic arm (204) to be maneuverer along the X, Y and Z planes. One end of the robotic arm (204) may be coupled to the heating unit provided in the deposition head (102) whereas, the other end of the robotic arm (204) may be firmly mounted or supported on a floor. The deposition head (102) includes at least one heating element which locally melts the feeder material (114) received from the feeder unit (202) and deposits the molten material onto the base (206). The heat produced by the heating element is controlled depending upon the feeder material used.

Referring now to FIGS. 2 and 3 which are schematic representations of an attachment device (100) for supporting material deposited by an additive manufacturing machine (200). As illustrated in FIGS. 2 and 3, the device (100) includes, a support bracket (104), a connecting rod (106), an adjusting mechanism (108), guiding members (110) and fasteners (112). The support bracket (104) is provided such that it is removably attached to the deposition head (102) of the additive manufacturing machine (200). The support bracket (104) may further have grooves across its length for accommodating deposition heads (102) of various sizes. A plurality of connecting rods (106) are provided such that said connecting rods (106) extends on either sides of the deposition head (102) towards the tip of the deposition head (102). The connecting rods (106) may be made up of at least one of but not limited to copper, aluminum, iron, etc. In some embodiments, the connecting rods (106) can be telescopic in nature such that the length can be adjusted as per the need.

Further, the device (100) includes a guiding member (110) provided such that it is configured to be supported by the plurality of connecting rods (106). The guiding members (110) may be permanently joined to the connecting rods by at least one of but limited to welding, brazing, etc. or removably fixed using mechanical joining process. In an embodiment, the connecting rods (106) are made up of heavy gauged high strength steel to resist bending or twisting during robotic arm (204) movement. Moreover, the opposing sides of each of the guiding member (110) defines a space to receive and support the material deposited by the additive manufacturing machine (200). The device (100) further includes an adjusting mechanism, wherein the adjusting mechanism has an adjustment screw provided in between the at least one connecting rods (106) that extends from either sides of the deposition head (102). The adjusting mechanism is configured to adjust the space between the guiding members (110) to control at least one parameter of the deposited material such as thickness of the deposited material, angle of the deposited material, height of the deposited material, etc. Further, the attachment device (100) may be flexibly attached to the deposition head (102). The connecting rods (106) may be provided with a groove for accommodating one side of the spring [not shown in Fig.] while the other end of the spring may be connected to deposition head (102) to help in keeping the guiding members (110) in contact with the deposited material at all times while still having flexibility for movement. Furthermore, the internal surface of the guiding members (110) may be provided at an angle or with a design to meet the required deposition shape of the deposited material.

In an embodiment, the support bracket (104) is at least one of a clamp defined with holes and grooves to adjust the width between the plurality of connecting rods (106) at the first ends. During the wire arc additive manufacturing process, the surface of the guiding members (110) is always kept in contact with the deposited layer such that the deposited hot metal or material is restrained, cooled, and is continuously subjected to slight casting and solidification forming under the restrain of the guiding members (110). This configuration allows the surface quality of the wall of the structure to be smooth and free of any surface imperfections. In an embodiment, the guiding members (110) maybe made up of a heat conducting material such as but not limited to copper, aluminium, etc and work as heat dissipating channels to control the inter layer temperature. Since the guiding members (110) are actuated, they provide the molten material a specific form instead of uncontrolled spillage or rupture during solidification of the molten material. This inherently creates a smoother surface finish on the product.

In an experimental embodiment, the deposition head (102) is provided in direction perpendicular to the base (206). The wire feeder unit (202) is provided with the feeder material (114) having a diameter of 1.2mm and shielding gas mixture containing 82% argon and 18% carbon dioxide at a constant rate to the deposition head (102). The deposition parameters such as current of 65A, voltage of 9.5V and travel speed of 300mm/min were chosen to achieve a total heat output of 105J/mm. Further, rate of feeder material is selected to be about 5.5m/min and the robotic arm movement was selected at 300cm/min. As a result, with the above conditions a uniform bead width is observed along the pre-determined path with a bead height of 1.5mm. Once, the layer of molten metal has been overlayed over a first layer, the robotic arm (204) may maneuver a nozzle and deposition head (102) along the vertical direction. The deposition head (102) may be maneuvered such that the height between the tip of the nozzle and the surface of the first layer increases. The height at which the deposition unit (102) is maneuvered vertically may vary based on the thickness and the height of the overlayed metal. The deposition head (102) may subsequently stack another layer of molten metal on the already overlayed layer of metal. This process of overlaying a layer of molten metal and increasing the height of the deposition head (102) along the vertical direction may be repeated unit the desired height of the wall is achieved. The above-mentioned deposition parameters must not be construed as a limitation as it is obvious to a person skilled in the art that the same may be varied by changing the various operational parameters.

In an embodiment, the guided members controls the deposition shape and avoids the stacking faults.

In an embodiment, the device of the present disclosure avoids the need of additional machinery, part costs and associated labor costs by providing required finish in real-time during the additive manufacturing process.

Equivalents

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding the description may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated in the description.

Referral Numerals:

Device 100
Deposition Head 102
Support bracket 104
Connecting Rod 106
Adjusting mechanism 108
Guiding members 110
Fasteners 112
Feeder material 114
Addictive manufacturing machine 200
Feeder unit 202
Robotic arm 204
Base 206

Claims:We claim:

1. A device (100) for supporting material deposited by an additive manufacturing machine (200), the device (100) comprising:
a support bracket (104) removably attached to a deposition head (102) of the additive manufacturing machine (200),
at least one connecting rod (106) extending from the support bracket (104) on either sides of the deposition head (102) towards a tip of the deposition head (102); and
a guiding member (110) supported by each of the at least one connecting rod (106), wherein, opposing sides of each of the guiding member (110) defines a space to receive and support the material deposited by the additive manufacturing machine (200).

2. The device (100) as claimed in claim 1 comprises an adjusting mechanism (108) provided between the at least one connecting rod (106) extending from either sides of the deposition head (102), wherein the adjusting mechanism (108) is configured to adjust the space between the guiding members (110).

3. The device (100) as claimed in claim 1, wherein each of the at least one connecting rod (106) is connected to the support bracket (104) through a plurality of fasteners (112).

4. The device (100) as claimed in claim 1, wherein the guiding member (110) is connected to each of the at least one connecting rod (106) through the plurality of fasteners (112).

5. The device (100) as claimed in claim 1, wherein the guiding member (110) is made of a thermally conductive material to dissipate heat generated during deposition of the material.

6. The device (100) as claimed in claim 1, wherein the additive manufacturing machine (200) is a wire arc additive manufacturing machine (200).

7. An additive manufacturing machine (200), comprising:
a robotic arm (204);
a deposition head (102) coupled to the robotic arm (204), wherein the robotic arm (204) is communicatively coupled to a control unit, and wherein the control unit is configured to operate the robotic arm (204) to traverse the deposition head (102) in a predetermined pattern for depositing a material on a base (206);
a device (100) supporting the material deposited by the deposition head (102), the device (100) comprising:
a support bracket (104) removably attached to the deposition head (102),
at least one connecting rod (106) extending from the support bracket (104) on either sides of the deposition head (102) towards a tip of the deposition head (102); and
a guiding member (110) supported by each of the at least one connecting rod (106), wherein, opposing sides of each of the guiding member (110) defines a space to receive and support the material deposited by the additive manufacturing machine (200).

8. The additive manufacturing machine (200) as claimed in claim 7 is a wire arc additive manufacturing machine (200).

9. The additive manufacturing machine (200) as claimed in claim 7 comprises a wire feeder unit (202), wherein the wire feeder unit (202) is coupled to the robotic arm (204) for feeding material through the deposition head (102).

10. The system as claimed in claim 7, wherein the deposition head (102) is aligned perpendicular to the base (206).

11. The system as claimed in claim 7 comprises a heating unit provided in the deposition head (102) for heating and fusing, a feeder material (114) on the base (206).