Laminated object manufacturing system

• US 5,730,817 A
• Filed: 04/22/1996
• Issued: 03/24/1998
• Est. Priority Date: 04/22/1996
• Status: Expired due to Term

• Current Assignee: Cubic Technologies, Inc.
• Original Assignee: Helisys, Inc.
• Inventors: Diamond, Michael N., Shkolnik, Alexandr, Dvorskiy, Emmanuil, Feygin, Michael
• Primary Examiner(s): AFTERGUT, JEFFRY H
• Application Number:
  US08/635,506
• Time in Patent Office: 701 Days
• Field of Search: 156/64, 156/358, 156/264, 156/512, 156/517, 156/516, 156/359, 156/256, 156/267
• US Class Current: 156/64
• CPC Class Codes: B29C 64/147 using sheet material, e.g. laminated object manufacturing [LOM] or laminating sheet material precut to local cross sections of the 3D object
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B32B 2309/02 Temperature
• CPC Class Codes: B32B 2309/12 Pressure
• CPC Class Codes: B32B 2309/72 For measuring or regulating, e.g. systems with feedback loops
• CPC Class Codes: B32B 37/1045 Intermittent pressing, e.g. by oscillating or reciprocating motion of the pressing means B32B37/0076 takes precedence
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: Y10T 156/1062 Prior to assembly
• CPC Class Codes: Y10T 156/1075 of plural laminae from single stock and assembling to each other or to additional lamina
• CPC Class Codes: Y10T 156/108 Flash, trim or excess removal
• CPC Class Codes: Y10T 156/13 Severing followed by associating with part from same source
• CPC Class Codes: Y10T 156/1317 Means feeding plural workpieces to be joined
• CPC Class Codes: Y10T 156/1322 Severing before bonding or assembling of parts

Abstract

A laminated object manufacturing (LOM) system for forming a plurality of laminations into a stack to create a three-dimensional object. The system includes an X-Y plotter device positioned above a work table, the work table being vertically movable. The X-Y plotter device includes a forming tool for forming a layer from a sheet of material positioned on the work table. The layers are bonded to each other with heat sensitive adhesives provided on one side thereof. A bonding tool or fuser is mounted to translate across the work table and apply a lamination force and heat to each of the layers. The X-Y plotter device and bonding tool are mounted to translate along rails mounted on a common reference frame. The reference frame includes two rigid beams positioned on a base frame. A sensor is provided between the bonding tool and the reference frame to sense the force applied by the bonding tool to the laminations and adjust the height of the work table in response thereto. An infrared sensor senses the temperature of the layers to also provide feedback to a control device for adjusting the speed of the bonding tool. The forming tool may be a laser system which includes a laser mounted to the reference frame, a plurality of mirrors, and a lens mounted on the X-Y plotter device.

Claims

1. A laminated object manufacturing system for converting sheet material into a three-dimensional object comprised of a plurality of layers of said sheet material, comprising:

a base frame;

a reference frame on said base frame, the reference frame comprising at least one reference frame member comprised of first and second rail portions disposed on a common support structure portion;

a work station adapted to position said sheet material relative to said reference frame;

a forming tool movably mounted on said first rail portion, said forming tool being driven to move relative to said work station so as to form said layers from the sheet material;

a bonding tool movably mounted on said second rail portion, said bonding tool being driven to move relative to said work station so as to bond adjacent layers of said sheet material to each other; and

a controller which electronically controls the movements of said forming tool and said bonding tool.

2. The system of claim 1, wherein said reference frame comprises two reference frame members.

3. The system of claim 2, wherein the work station defines a horizontal work surface, and the two reference frame members are mounted on the base frame in parallel adjacent the work surface, the forming tool and bonding tool being movably mounted on the first and second rail portions, respectively, of both reference frame members.

4. The system of claim 1, wherein said support structure portion comprises a first beam and wherein the system additionally comprises a second reference frame member having first and second rail portions disposed on a common second beam, said first and second beams being mounted on opposite sides of said work station, wherein said forming tool is mounted on the first rail portions of said first and second beams, and said bonding tool is mounted on the second rail portions of said first and second beams.

5. The system of claim 1, wherein said work station is mounted to move with respect to said reference frame.

6. The system of claim 5, wherein the work station comprises a work table mounted on an elevator mechanism enabling vertical positioning of the work table with respect to the reference frame, and wherein the forming tool and bonding tool are movably mounted in an X-Y plane perpendicular to the vertical axis.

7. The system of claim 1, further including a sheet material feed system for providing a continuous web of sheet material across the work station, wherein the reference frame is mounted above the work station so that the forming tool and the bonding tool translate over the sheet material.

8. The system of claim 1, further comprising:

an X-Y plotter mounted on said reference frame member and defining a portion of said forming tool;

a laser mounted on said reference frame member for producing a laser beam; and

at least one mirror mounted on said reference frame member to receive said laser beam and direct the beam onto said sheet material.

9. The system of claim 1, further comprising:

a sensor mounted to sense the force applied by said bonding tool to the sheet material during bonding of said adjacent layer; and

wherein said controller electronically controls the position of said bonding tool with respect to said work station in accordance with the force sensed by said sensor.

10. The system of claim 1, further comprising:

a temperature sensor mounted to sense the temperature of an exposed layer of sheet material that has been bonded to other layers; and

wherein said controller controls the speed of said bonding tool relative to said work station in accordance with the temperature sensed by said temperature sensor.

11. A laminated object manufacturing system for converting sheet material into a three-dimensional object comprised of a plurality of layer of said sheet material, comprising:

a base frame;

a reference frame on said base frame, the reference frame comprising at least one reference frame member;

a work station mounted to position said sheet material;

a forming tool comprising an X-Y plotter, a laser for producing a laser beam and at least one mirror to receive said laser beam and direct the beam onto said sheet material, wherein said X-Y plotter, said laser, and said mirror are mounted on the same said reference frame member.

12. The system of claim 11, wherein said mirror is mounted in a fixed position with respect to said reference frame and the system further includes a second mirror movably mounted with respect to said reference frame on a portion of said X-Y plotter.

13. The system of claim 11, wherein said reference frame member comprises first and second rail portions disposed on a common support structure portion;

and

a bonding tool movably mounted on said second rail portion, said bonding tool being driven to move relative to said work station so as to bond adjacent layers of said sheet material to each other.

14. The system of claim 13, further comprising:

a temperature sensor mounted to sense the temperature of an exposed layer of sheet material that has been bonded to other layers; and

wherein said controller controls the speed of said bonding tool relative to said work station in accordance with the temperature sensed by said temperature sensor.

15. The system of claim 13, further including an infrared sensor mounted on the reference frame above the work station to sense the temperature at one or more points on an exposed layer of sheet material that has been bonded to other layers.

16. The system of claim 11, wherein said reference frame comprises two reference frame members and wherein the work station defines a horizontal work surface, and the two reference frame members are mounted on the base frame in parallel adjacent the work surface, the forming tool and bonding tool being movably mounted on the first and second rail portions, respectively, of both reference frame members.

17. The system of claim 11, further including an elongated knife duct and an elongated vacuum duct positioned on opposite sides of the work station and a blower fan adapted to blow air through the knife duct across the work station to the exhaust duct to remove unwanted smoke or other particles from above the work station which might interfere with the operation of the laser.

18. The system of claim 11, wherein the reference frame comprises two reference frame members each having rail portions disposed on a support structure portion, and the X-Y plotter comprises motor driven pulleys and belts attached to X-axis carriages mounted on linear bearings to said rail portions.

19. The system of claim 18, wherein the X,Y plotter additionally comprises a lateral support mounted across the reference frame members and including a rail, each end of the lateral support being mounted to one of said X-axis carriages and adapted to slide linearly along the rail portions of the reference frame members, the forming tool being mounted to a Y-axis carriage adapted to slide linearly along the rail of the lateral support.

20. A laminated object manufacturing system for converting sheet material into a three-dimensional object comprised of a plurality of layers of said sheet material, comprising:

a work station mounted to position said sheet material;

a forming tool mounted to move relative to said work station to form said layers from the sheet material;

a bonding tool mounted to move relative to said work station to apply force and bond adjacent layers of sheet material to each other to form said three-dimensional object;

at least two spaced sensors on said bonding tool mounted to sense the force applied by said bonding tool to the sheet material during bonding of said adjacent layers;

a controller which electronically controls the position of said bonding tool with respect to said work station in accordance with the force sensed by said sensor to ensure proper bonding of the adjacent layers of sheet material.

21. The system of claim 20, wherein said reference frame comprises two reference frame members and wherein the work station defines a horizontal work surface, and the two reference frame members are mounted on the base frame in parallel adjacent the work surface, the bonding tool being movably mounted across the reference frame members.

22. The system of claim 21, wherein said two reference frame members include rail portions and wherein said bonding tool comprises a roller spring-mounted on each end to a carriage adapted to slide on said rail portions, and said sensors comprise position sensors for sensing the relative position of each end of the roller with respect to the associated carriage, which along with the spring constants of the spring mounts is used to determine the force applied by said roller to the sheet material.

23. A laminated object manufacturing system for converting sheet material into a three-dimensional object comprised of a plurality of layers of said sheet material, comprising:

a work station adapted to position said sheet material;

a forming tool mounted to move relative to said work station to form said layers from the sheet material;

a bonding tool mounted to move relative to said work station to bond adjacent layers of sheet material to each other to form said three-dimensional object;

a temperature sensor mounted to sense the temperature of an exposed layer of sheet material that has been bonded to other layers; and

a controller which controls the application of heat to a layer of sheet material that is applied to said exposed layer, said controller controlling said application of heat in accordance with the temperature sensed by said temperature sensor.

24. The system of claim 23, wherein the temperature sensor comprises an infrared sensor.

25. The system of claim 23, further including a reference frame comprising two reference frame members and wherein the work station defines a horizontal work surface, and the two reference frame members are mounted on the base frame in parallel adjacent the work surface, the system further including:

an X-Y plotter mounted on said reference frame members and defining a portion of said forming tool, wherein said temperature sensor is mounted on said X-Y plotter over said horizontal work surface.

26. The system of claim 25, wherein the reference frame members each have rail portions disposed on a support structure portion, and the X-Y plotter comprises motor driven pulleys and belts attached to X-axis carriages mounted on linear bearings to said rail portions, the X,Y plotter additionally comprising a lateral support mounted across the reference frame members, wherein said temperature sensor is mounted on said lateral support.

27. The system of claim 23, wherein said bonding tool applies said heat to said layer of sheet material that is applied to said exposed layer.

28. The system of claim 23, wherein said controller controls the speed of said bonding tool relative to said work station in accordance with the temperature sensed by said temperature sensor.

29. A method of converting sheet material into a three-dimensional object comprised of a plurality of layers, including the steps of:

positioning said sheet material over a work station;

forming a layer from the sheet material using a forming tool movably mounted over the work station;

bonding said formed layer to an adjacent layer of sheet material to result in a bonded layer using a bonding tool movably mounted over the work station;

sensing the temperature of the sheet material;

adjusting the speed of the bonding tool on a subsequent bonding step based on the temperature sensed.

30. The method of claim 29, further comprising the steps of:

monitoring the speed of the bonding tool relative to a maximum reference speed; and

reducing the temperature of the bonding tool when the speed of the bonding tool reaches said reference speed.

31. The method of claim 29, further comprising the steps of:

monitoring the speed of the bonding tool relative to a minimum reference speed; and

increasing the temperature of the bonding tool when the speed of the bonding tool reaches said reference speed.

32. The method of claim 29, wherein said step of sensing comprises sensing the temperature of the formed layer before said formed layer is bonded to an adjacent layer.

33. The method of claim 29, wherein said step of sensing comprises sensing the temperature of the bonded layer.

34. The method of claim 29, wherein said step of sensing comprises sensing the temperature of said sheet material at more than one position between said steps of bonding.

35. A method of converting sheet material into a three-dimensional object comprised of a plurality of layers of said sheet material, comprising the steps of:

positioning said sheet material over a work station;

forming a layer from the sheet material using a forming tool movably mounted over the work station;

bonding said formed layer to an adjacent layer of sheet material using a bonding tool movably mounted over the work station;

sensing the force applied by the bonding tool to the sheet material during bonding of said layer; and

controlling the position of the bonding tool with respect to the work station in accordance with the force sensed by the sensor.

36. The method of claim 35, wherein said bonding tool is a roller and said step of sensing comprises sensing the force at both ends of said roller applied by contact between said roller and said formed layer.

37. The method of claim 36, wherein said roller is spring-mounted at both ends to a movable carriage and the step of sensing comprises sensing the relative position of each end of the roller with respect to the carriages, which, along with the spring constants of the spring mounts, is used to determine the force applied by said roller to the sheet material.

38. A laminated object manufacturing system for converting sheet material into a three-dimensional object comprised of a plurality of layers of said sheet material, comprising:

a work station adapted to position said sheet material;

a forming tool mounted to move relative to said work station to form said layers from the sheet material;

a bonding tool mounted to move relative to said work station to bond adjacent layers of sheet material to each other, said bonding tool contacting said sheet material in a first position to begin bonding and moving to a second position to complete bonding while maintaining contact with said sheet material between the first and second positions; and

first and second rolls, said sheet material extending between the rolls and across the work station, said first roll feeding said sheet material to said work station and said second roll receiving the material from the work station such that material proximate to the work station is under tension, said system releasing the tension after said bonding tool is in said first position, and restoring tension subsequent to said bonding tool reaching said second position.

39. The system of claim 38, wherein said second rail is a windup roll driven by a reversible motor, wherein said motor places said sheet in tension by rotation in a first direction, and releases the tension from said sheet by rotating in an opposite direction.

40. The system of claim 38, wherein said second roll is a pinch roll mounted on a top surface of said system adjacent said work station, the system further including a third roll which receives said sheet material from said pinch rolls and stores said sheet material, said pinch roll being driven by a reversible motor wherein the tension is applied to the sheet by rotating the motor in a first direction, and the tension is released from the sheet by rotating the motor in an opposite direction.

41. A method of converting sheet material into a three-dimensional object comprised of a plurality of layers, comprising:

sensing the temperature of an exposed layer of sheet material that has been bonded to other layers to form a portion of said object;

applying a subsequent layer of sheet material to said exposed layer;

heating said subsequent layer;

controlling the heating of the subsequent layer in accordance with the sensed temperature of said exposed layer.