Consumable friction reverse additive manufacturing device and additive manufacturing method

Abstract

The invention provides a consumable friction reverse material adding device and a material adding manufacturing method. The consumable friction reverse material adding device comprises a support, an inner base plate, a pressing plate, a cutter, a metal bar and a pressure applying assembly. The support is used for supporting and fixing parts. The inner base plate is connected to the support and provided with a forming groove. The pressing plate is arranged on the part and used for clamping and fixing the part; the cutter is provided with a feeding channel; the metal bar is arranged in the feeding channel in a penetrating mode and arranged on the surface, deviating from the forming groove, of the part. The pressure applying assembly is used for applying loading force to the metal bar so as to drive the metal bar to move. During machining, large-area milling and thinning on the cylinder wall of the part are avoided, only local part of the inward convex structure needs to be machined, the material removal amount is small, the machining period is short, and the machining cost is low.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and more specifically, to a consumable friction reverse additive device and an additive manufacturing method. Background Art

[0002] At present, the inner boss processing method of the cylindrical component is: on the cylindrical blank with a larger wall thickness, various bosses are processed from the inside by milling. In this processing process, the wall thickness of the cylindrical blank needs to be thinned from the inside over a large area, the material removal amount is large, the processing cycle is long, and the processing cost is high. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] The technical problem to be solved by the present invention is that the cylindrical component processed by the existing processing method has a large amount of material removal, a long processing cycle and a high processing cost.

[0005] (II) Technical solution

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] In the first aspect, the present invention provides a consumable friction reverse additive device, comprising a bracket, an inner pad, a pressure plate, a tool, a metal bar and a pressure assembly; the bracket is used to support and fix the part; the inner pad is connected to the bracket, and the inner pad has a molding groove; the pressure plate is arranged on the part and is used to clamp and fix the part; the tool has a feeding channel; the metal bar is passed through the feeding channel and is arranged on the surface of the part away from the molding groove; the pressure assembly is used to apply a load force to the metal bar to drive the metal bar to move.

[0008] Preferably, it also includes a base, which is connected to the bracket and arranged on the side of the bracket away from the tool.

[0009] Preferably, the cross-sectional shape of the metal bar is an axisymmetric shape.

[0010] Preferably, the bottom of the knife is flat or has a groove.

[0011] In a second aspect, the present invention provides an additive manufacturing method, using the consumable friction reverse additive device described in any one of the above technical solutions to additively manufacture a cylindrical component, wherein the cylindrical component has an inner convex structure, comprising the following steps:

[0012] The cylindrical component is mounted on the inner backing plate, the position of the inner convex structure to be added corresponds to the position of the molding groove, and the cylindrical component is pressed by a pressing plate so that the inner surface of the cylindrical component is attached to and fixed to the inner backing plate;

[0013] The bottom end of the metal bar is moved to the position of the inner convex structure to be added, and the bottom end of the metal bar is pressed against the outer surface of the cylindrical component away from the forming groove;

[0014] The tool and the metal bar are driven to rotate at a preset speed, and the pressure component applies a constant preset pressure to the metal bar to push the metal bar to move;

[0015] The bottom of the high-speed rotating metal bar contacts and stirs with the outer surface of the cylindrical component to generate heat, which is converted into a thermoplastic material. The thermoplastic material is squeezed and filled with the molding groove and the cylindrical wall of the cylindrical component under the load force applied by the pressure component.

[0016] The metal bar material is separated from the wall of the cylindrical component, and the thermoplastic material is cooled to form an inner convex structure;

[0017] The inner convex structure is machined to the final size by milling.

[0018] Preferably, a gap of 0-5 mm is reserved between the bottom surface of the tool and the outer surface of the cylindrical component.

[0019] Preferably, the preset speed is 100rpm-3000rpm; the preset pressure is 100N-20000N.

[0020] Preferably, the size of the molding groove is 0-20% larger than the size of the inner convex structure.

[0021] Preferably, when the inner convex structure is a circular inner boss, the distance between the two farthest points of the cross section of the selected metal bar is not less than 50% of the diameter of the circular inner boss, and the diameter of the bottom of the selected tool is not less than 120% of the diameter of the circular inner boss;

[0022] Preferably, when the inner convex structure is a strip-shaped inner boss and an annular inner boss, the distance between the two farthest points of the cross-section of the selected metal bar is not less than 80% of the width of the strip-shaped inner boss and the annular inner boss, and the diameter of the bottom of the selected tool is not less than 120% of the width of the strip-shaped inner boss and the annular inner boss.

[0023] Preferably, a through slot is provided at a position of the cylindrical member corresponding to the inner convex structure, and a width of the through slot is not greater than 80% of a distance between two farthest points of a cross section of the metal bar.

[0024] (III) Beneficial effects

[0025] The above technical solution of the present invention has at least the following advantages:

[0026] In the present invention, the part is fixedly mounted on the bracket by a pressure plate, a tool is arranged on the surface of the part away from the forming groove, the tool is driven to rotate, and then the metal bar is driven to rotate, the pressure component applies a load force to the metal bar to push the metal bar to move, the metal bar and the part generate heat by friction, and the thermoplastic material formed by heating flows into the forming groove under the extrusion of the metal bar, and is formed into an inner convex structure connected to the part under the limiting effect of the forming groove. The present invention can locally add an inner convex structure to the cylindrical component, and then use the milling method to process it to the final size. This method avoids the traditional processing method of large-scale milling and thinning of the cylindrical wall of the cylindrical component, and only the local part of the inner convex structure is processed, the material removal amount is small, the processing cycle is short, and the processing cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a schematic structural diagram of a consumable friction reverse additive device provided in an embodiment of the present invention.

[0029] Figure 2 It is a cross-sectional view of a consumable friction reverse additive device provided in an embodiment of the present invention.

[0030] Figure 3 It is a schematic structural diagram of a cylindrical component provided by an embodiment of the present invention.

[0031] Figure 4 It is a schematic structural diagram of a cylindrical component provided by an embodiment of the present invention in which a through groove is provided.

[0032] Figure 5 It is a schematic diagram of the use principle of the consumable friction reverse additive device provided in an embodiment of the present invention.

[0033] Figure 6 This is one of the structural schematic diagrams of the tool provided by the embodiment of the present invention.

[0034] Figure 7 This is the second structural schematic diagram of the tool provided by the embodiment of the present invention.

[0035] Figure 8 It is a schematic diagram of the cross-sectional shape of the metal bar provided in an embodiment of the present invention.

[0036] The reference numerals in the figures are:

[0037] 10. Parts; 20. Inner convex structure; 1. Bracket; 2. Inner pad; 3. Pressing plate; 4. Cutting tool; 5. Metal bar; 6. Base; 21. Forming groove; 41. Groove; 201. Through groove. DETAILED DESCRIPTION

[0038] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0039] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly located on the other element or indirectly located on the other element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element.

[0040] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention, and do not indicate that a device or element must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0041] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating relative importance or indicating the number of technical features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The specific implementation of the present invention is described in more detail below in conjunction with specific embodiments:

[0042] like Figure 1 , Figure 2 , Figure 3 and Figure 5As shown, an embodiment of the present invention provides a consumable friction reverse additive device, including a bracket 1, an inner pad 2, a pressure plate 3, a tool 4, a metal bar 5 and a pressure assembly (not shown); the bracket 1 is used to support and fix the part 10; the inner pad 2 is connected to the bracket 1, and the inner pad 2 has a molding groove 21; the pressure plate 3 is arranged on the part 10, and is used to clamp and fix the part 10; the tool 4 has a feeding channel; the metal bar 5 is passed through the feeding channel and is arranged on the surface of the part 10 away from the molding groove 21; the pressure assembly is used to apply a load force to the metal bar 5 to drive the metal bar 5 to move. Specifically, the part 10 can be clamped and fixed by the bracket 1 and the pressure plate 3, and then the tool 4 is driven to rotate on the surface of the part 10 away from the molding groove 21, so that the metal bar 5 and the part 10 generate heat by friction, forming a thermoplastic material. With the continuous friction of the metal bar 5, the thermoplastic material generated by heating flows into the molding groove 21, forming an inner convex structure 20 connected to the part 10, thereby realizing the reverse additive manufacturing of the inner convex structure 20 on the part 10. According to the shape and size of the inner convex structure 20, a molding groove 21 of a corresponding shape and size can be specifically selected. Specifically, the pressure component is an oil cylinder or a gear component connected to the output end of the motor, and the metal bar 5 is pushed to move by the output end of the oil cylinder, or the gear component is driven to rotate by the motor, and then the metal bar 6 is driven to move by the gear component.

[0043] In one embodiment, a base 6 is further included, the base 6 is connected to the bracket 1, and the base 6 is arranged on the side of the bracket 1 away from the tool 4. The base 6 is preferably a flat plate structure to facilitate stable placement on a horizontal plane.

[0044] like Figure 8 As shown, in one embodiment, the cross-sectional shape of the metal bar 5 is an axisymmetric shape. Specifically, the axisymmetric shape can be square, circular, etc. More specifically, when the cross-sectional shape of the metal bar 5 is square, its diagonal size ranges from 5mm to 50mm; when the cross-sectional shape of the metal bar 5 is circular, its diameter ranges from 5mm to 50mm; when the cross-sectional shape of the metal bar 5 is other cross-sectional shapes, the distance between the farthest two points on the cross-sectional shape ranges from 5mm to 50mm.

[0045] like Figure 6 and Figure 7 As shown, in one embodiment, the bottom of the tool 4 is flat or has a groove. The gap between the tool 4 and the outer surface of the part 10 ranges from 0 to 5 mm, and the main function is to flatten the upper surface of the additive layer.

[0046] like Figure 1 , Figure 2 , Figure 3 and Figure 5As shown, an embodiment of the present invention provides an additive manufacturing method, using any of the consumable friction reverse additive devices in the above embodiments to additively manufacture a part 10, the part 10 is specifically a cylindrical component, the cylindrical component has an inner convex structure 20, and the additive manufacturing method includes the following steps:

[0047] The cylindrical component is mounted on the inner pad 2, the position of the inner convex structure 20 to be added corresponds to the position of the molding groove 21, and the pressing plate 3 is used to press the cylindrical component so that the inner surface of the cylindrical component is attached to and fixed to the inner pad 2;

[0048] Move the bottom end of the metal bar 5 to the position of the inner convex structure 20 to be added, and the bottom end of the metal bar 5 abuts against the outer surface of the cylindrical component away from the forming groove 21;

[0049] The tool 4 and the metal bar 5 are driven to rotate at a preset speed, and the pressure component applies a constant preset pressure to the metal bar 5 to push the metal bar 5 to move;

[0050] The bottom of the high-speed rotating metal bar 5 contacts the outer surface of the cylindrical component to generate heat through friction and stirring, and is converted into a thermoplastic material. The thermoplastic material is squeezed and filled with the forming groove 21 and the cylinder wall of the cylindrical component under the load force applied by the pressure component; specifically, the bottom of the metal bar 5 and the cylinder wall of the cylindrical component that participate in the friction heat generation are heated and continuously converted into a thermoplastic material. At the same time, the downward pressure of the metal bar 5 squeezes the thermoplastic material to fill the forming groove 21 on the inner pad 2, and the thermoplastic material converted from the metal bar 5 is further filled on the cylinder wall of the cylindrical component.

[0051] The metal bar 5 is separated from the wall of the cylindrical component, and the thermoplastic material is cooled to form an inner convex structure 20;

[0052] The inner convex structure 20 is processed by milling to a final size.

[0053] In one embodiment, a gap of 0-5 mm is reserved between the bottom surface of the cutter 4 and the outer surface of the cylindrical component.

[0054] In one embodiment, the preset speed is 100rpm-3000rpm; the preset pressure is 100N-20000N.

[0055] In one embodiment, the size of the molding groove 21 is 0-20% larger than the size of the inner convex structure 20. Specifically, the size includes the circumferential size, the width size and the depth size, so as to reserve some size margin for machining.

[0056] In one embodiment, when the inner convex structure 20 is a circular inner boss, the distance between the two farthest points of the cross section of the selected metal bar 5 is not less than 50% of the diameter of the circular inner boss, and the diameter of the bottom of the selected tool 4 is not less than 120% of the diameter of the circular inner boss;

[0057] In one embodiment, when the inner convex structure 20 is a strip-shaped inner boss and an annular inner boss, the distance between the two farthest points of the cross section of the selected metal bar 5 is not less than 80% of the width diameter of the strip-shaped inner boss and the annular inner boss, and the diameter of the bottom of the selected tool 4 is not less than 120% of the width diameter of the strip-shaped inner boss and the annular inner boss.

[0058] like Figure 4 As shown, in one embodiment, a through groove 201 is provided at a position of the cylindrical member corresponding to the inner convex structure, and the width of the through groove 201 is not greater than 80% of the distance between the two farthest points of the cross section of the metal bar 5. The through groove 201 is used to promote the downward flow of the thermoplastic material, and the thermoplastic material can flow into the molding groove 21 through the through groove 201.

[0059] Embodiment 1:

[0060] The metal bar 5 is made of 6061 aluminum alloy metal bar, and the bar specifications are 20mm×20mm×450mm; the part 10 (cylindrical component) is made of 6061 square cylinder, and the cross-sectional specifications of the cylindrical component are: outer side length 300mm, wall thickness 5mm, the inner convex structure 20 is a circular inner boss, the size of the circular inner boss is Φ18mm, and the height is 8mm; the material of the inner pad 2 is stainless steel, and the specifications of the through groove 201 are: Φ20mm, depth 10mm.

[0061] Step 1: Install the cylindrical component onto the inner pad 2. The position of the circular inner boss to be added corresponds to the position of the molding groove 21 (circular in this embodiment) on the inner pad 2. Use the pressing plate 3 to press the part 10 so that the inner surface of the cylindrical wall of the cylindrical component is attached to and fixed to the inner pad 2.

[0062] Step 2: Move the bottom end of the metal bar 5 to the position of the circular inner boss to be added, and the bottom end of the metal bar 5 is against the outer surface of the cylindrical wall of the cylindrical component with a pressure value of 8000N. A gap of 2mm is reserved between the bottom surface of the tool 4 and the outer surface of the cylindrical component.

[0063] Step 3: Drive the cutter 4 and the metal bar 5 to rotate at a high speed, with the speed ranging from 100rpm to 3000rpm. At the same time, apply a constant downward pressure to the metal bar 5, with the pressure value ranging from 100N to 20000N.

[0064] Step 4: The bottom of the high-speed rotating metal bar 5 contacts and rubs against the outer surface of the cylindrical wall of the cylindrical component to generate heat; the bottom of the metal bar 5 and the cylindrical wall of the cylindrical component that participate in the frictional heat generation are heated and continuously converted into thermoplastic material. At the same time, the downward pressure of the metal bar 5 squeezes the thermoplastic material to fill the forming groove 21 on the inner pad 2, and the thermoplastic material converted from the metal bar 5 is further filled onto the cylindrical wall of the cylindrical component.

[0065] Step 5: The metal bar 5 is separated from the wall of the cylindrical component, and the thermoplastic material is cooled to form a circular inner boss.

[0066] Step 6: Use milling method to process the inner boss to the final size.

[0067] Embodiment 2:

[0068] The metal bar 5 is made of TC4 titanium alloy metal bar with a bar specification of Φ20mm; the part 10 (cylindrical component) is made of TC4 titanium alloy cylinder with an outer diameter of Φ220mm and a wall thickness of 3mm. The inner convex structure 20 is an annular inner boss with a size of 10mm in width and 5mm in height. The inner pad 2 is made of red copper material, and the through groove 201 is annular. The specifications of the through groove 201 are: width 12mm, depth 7mm.

[0069] Step 1: Install the cylindrical component onto the inner pad 2, and the position of the annular inner boss to be added corresponds to the position of the molding groove 21 (annular in this embodiment) on the inner pad 2. Use the internal support tooling to fit and fix the inner pad 2 to the inner surface of the cylindrical component.

[0070] Step 2: Move the bottom end of the metal bar 5 to the starting position of the annular inner boss to be added. The bottom end of the metal bar 5 is against the outer surface of the cylindrical wall of the cylindrical component with a pressure value of 12000N. A gap of 1.5mm is reserved between the bottom surface of the tool 4 and the outer surface of the cylindrical component.

[0071] Step 3: Drive the cutter 4 and the metal bar 5 to rotate at a high speed, with a speed range of 500rpm-3000rpm. At the same time, apply a constant downward pressure to the metal bar 5, with a pressure value range of 1000N-20000N.

[0072] Step 4: The bottom of the high-speed rotating metal bar 5 contacts and rubs against the outer surface of the cylindrical wall of the cylindrical component to generate heat; the bottom of the metal bar 5 and the cylindrical wall of the cylindrical component that participate in the frictional heat generation are heated and continuously converted into thermoplastic material. At the same time, the downward pressure of the metal bar 5 squeezes the thermoplastic material to fill the forming groove 21, and the thermoplastic material converted from the metal bar 5 is further filled onto the cylindrical wall of the cylindrical component.

[0073] Step 5: Start the tooling to make the cylindrical component rotate circumferentially at a constant speed of 5-30 mm / s. When the cylindrical component rotates one circle and the metal bar 5 returns to the starting material adding position, the metal bar 5 is separated from the cylindrical wall of the cylindrical component.

[0074] Step 6: Use milling method to process the annular inner boss to the final size.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A consumable friction reverse additive device, characterized in that: include: Bracket, used to support and fix parts; An inner pad, connected to the bracket, the inner pad having a formed groove; A pressing plate, disposed on the part, for clamping and fixing the part; A tool having a feeding channel; A metal bar material is passed through the feeding channel and is arranged on the surface of the part away from the forming groove; The pressure-applying assembly is used to apply a load force to the metal bar to drive the metal bar to move.

2. The consumable friction reverse additive device according to claim 1, characterized in that: It also includes a base, which is connected to the bracket and is arranged on a side of the bracket away from the tool.

3. The consumable friction reverse additive device according to claim 1, characterized in that: The cross-sectional shape of the metal bar is an axisymmetric shape.

4. The consumable friction reverse additive device according to claim 1, characterized in that: The bottom of the knife is flat or has a groove.

5. An additive manufacturing method, using the consumable friction reverse additive device according to any one of claims 1 to 4 to additively manufacture a cylindrical component, wherein the cylindrical component has an inner convex structure, characterized in that: The following steps are involved: The cylindrical component is mounted on the inner backing plate, the position of the inner convex structure to be added corresponds to the position of the molding groove, and the cylindrical component is pressed by a pressing plate so that the inner surface of the cylindrical component is attached to and fixed to the inner backing plate; The bottom end of the metal bar is moved to the position of the inner convex structure to be added, and the bottom end of the metal bar is pressed against the outer surface of the cylindrical component away from the forming groove; The tool and the metal bar are driven to rotate at a preset speed, and the pressure component applies a constant preset pressure to the metal bar to push the metal bar to move; The bottom of the high-speed rotating metal bar contacts and stirs with the outer surface of the cylindrical component to generate heat, which is converted into a thermoplastic material. The thermoplastic material is squeezed and filled with the molding groove and the cylindrical wall of the cylindrical component under the load force applied by the pressure component. The metal bar material is separated from the wall of the cylindrical component, and the thermoplastic material is cooled to form an inner convex structure; The inner convex structure is machined to the final size by milling.

6. The additive manufacturing method according to claim 5, characterized in that: A gap of 0-5 mm is reserved between the bottom surface of the tool and the outer surface of the cylindrical component.

7. The additive manufacturing method according to claim 5, characterized in that: The preset speed is 100rpm-3000rpm; the preset pressure is 100N-20000N.

8. The additive manufacturing method according to claim 5, characterized in that: The size of the molding groove is 0-20% larger than the size of the inner convex structure.

9. The additive manufacturing method according to claim 5, characterized in that: When the inner convex structure is a circular inner boss, the distance between the two farthest points of the cross section of the selected metal bar is not less than 50% of the diameter of the circular inner boss, and the diameter of the bottom of the selected tool is not less than 120% of the diameter of the circular inner boss; When the inner convex structure is a strip inner boss and an annular inner boss, the distance between the two farthest points of the cross section of the selected metal bar is not less than 80% of the width of the strip inner boss and the annular inner boss, and the diameter of the bottom of the selected tool is not less than 120% of the width of the strip inner boss and the annular inner boss.

10. The additive manufacturing method according to claim 5, characterized in that: A through slot is provided at a position of the cylindrical component corresponding to the inner convex structure, and a width of the through slot is not greater than 80% of the distance between the two farthest points of the cross section of the metal bar.

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