GB2436539A

GB2436539A - Combined light emitting diode and extrusion carriage for use on three dimensional modelling machines

Info

Publication number: GB2436539A
Application number: GB0606482A
Authority: GB
Inventors: John Tebbitt
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-03-31
Filing date: 2006-03-31
Publication date: 2007-10-03
Also published as: GB0606482D0

Abstract

The invention relates to a combined Light Emitting Diode (L.E.D) and extrusion carriage used on a three dimensional modelling machine such as that used in Fused Deposition Modelling (F.D.M). A nozzle (4 figure 2) builds a perimeter wall in multi layers of a formulated transparent but weak material that may be easily removed from the model when finished. The perimeter wall 2 (figure 2) width is determined by setting a centre rod 12 (figure 4) that allows a lifting bar 7-1 (figure 5) to open one, two 7-2 (figure 6) or three sections 7-1-2-3 (figure 4). The three sections allow material for a support platform matching the size of the produced model to be laid down without any wastage. When the model shape 6 (figure 2) and the outer wall 2 (figure 2) have been built to the same level, the extrusion carriage 1 is lowered under computer control to a distance above the previous material without opening the lifting bar 7-1-2-3 (figure 4). The Light Emitting Diodes 10 are switched on and the extrusion carriage 1 travels along the area of the model and perimeter wall curing the material. On the return movement the extrusion carriage 1 is lowered on top of the cured perimeter wall which automatically opens the lifting bar against spring pressure 8 (figure 4) and releases the infill support platform material followed by a levelling blade 9 which is then followed by an array of Light Emitting Diodes 10 which cures and sets the infill support platform material.

Description

TITLE OF INVENTION

A method and process for building a support platform used on 3 dimensional modelling machines using 6 combined light emitting diodes (L.E.D.) and extrusion carriage.

BACKGROUND TO INVENTION

This invention refers to a process for making 3 dimensional objects or models by producing multi layers of material to a predetermined shape produced by a C.A.D. (Computer Aided Design) system.

Such prior art systems are known as rapid prototyping or model making machines.

All work in different ways using different materials. Some use powders, resins, lasers, and Ultra Violet Light (UV) produced by mercury lamps and bulbs.

The apparatus to which this invention relates is a (F.D.M.) Fused Deposition Modelling machine which melts a variety of thermoplastics before depositing, chemical setting materials can also be used.

The disadvantages are slow build time, heat, fumes and complicated computer software to produce support structures which are necessary to support the model overhangs since the material cannot be suspended in free space.

Other disadvantages refer to systems which use UV light systems which uses a mercury light source which in some environments it is considered unsafe to use.

STATEMENT OF INVENTION

An automatic extrusion carriage to produce a support platform on 3 dimensional modelling machines incorporating an array of L.E.D.s which are mercury free used for UV light curing of both model and support materials.

ADVANTAGES

To overcome these disadvantages this invention is for a simple automatic extrusion carriage which produces a support platform (not a support structure) which eliminates the need for complicated computer software and by producing UV at room temperature using L.E.D.s which are mercury free.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 Shows the combined L.E.D. and extrusion carriage travelling along the outer wall of material.

Figure 2 A view of the outer wall being produced by one nozzle, and the model material being produced by a second nozzle. The infill support platform material is shown between the outer wall and the model material (Fig 2) 6.

Figure 3 End view of the extrusion carriage showing the lifting bar and the L.E.D.

Figure 4 This shows the lifting bar with 3 sections open and the centre rod.

Figure 5 A view of the lifting bar with 1 section open.

Figure 6 A view of the lifting bar with 2 sections open.

Figure 7 A view of the lifting bar in the open and closed position.

DESCRIPTION OF INVENTION

A bridge type 3 axis (X.YZ) robot or any similar apparatus, which is linked to any C.A.D.

(Computer Aided Design) software which exports S.T.L. (Stereolithography) files, is used to produce the shape of the model (Fig. 2) 6 in multi layers of material 0.25m/m to 5.OOmIm thick, by a conventional nozzle (Fig. 2) 3 using a specially formulated (U.V.) curable material in different colours, and unbreakable. A nozzle (Fig. 2) 4 builds a perimeter wall in multi layers of a specially formulated transparent weak material and easily removed from the model when finished. The width size of the perimeter wall (Fig. 2)2 is determined by setting the centre rod, (Fig. 4)12 to allow the lifting bar (Fig. 5) 7-1 to open 1 section, (Fig. 6)7-2 to open 2 sections, and (Fig. 4) 7-1-2-3 to open 3 sections. These 3 increments allow the area of the support platform material to match the size of the model being produced, without any wastage. The length of the perimeter wall is determined and controlled by the machine movement. When the model shape (Fig. 2) 6 and the outer perimeter wall (Fig. 2)2 has been built both to the same level, the extrusion carriage (Fig. 1) 1 is lowered (under computer control) to a distance above the previous material level without opening the lifting bar (Fig. 4) 7-1-2-3. The L.E.D.s (Fig 1)10 which are manufactured to a specific wavelength are switched on and the extrusion carriage (Fig. 1) 1 travels along the area of the model, and the perimeter wall material and is then cured and set. On the return movement the extrusion carriage (Fig. 1) 1 is lowered (under computer control) on top of the cured and set perimeter wall (Fig. 2)2 which automatically opens the lifting bar against the spring pressure (Fig. 4) 8 and releases the infill support platform material at a controlled volume and speed, followed by a levelling blade (Fig. 1) 9 which is then followed by an array of L.E.D.s (Fig. 1)10 which cures and sets the infill support platform material (Fig. 2) 5. At this stage the first layer of the process is completed.

Any residue of material left on the levelling blade (Fig. 1) 9 is cleaned against the end of the perimeter wall (Fig. 2) 2 at the beginning of the next layer cycle.

The process is repeated until the model is completed, when finished the model is enclosed within the transparent outer wall (Fig. 2) 2 and the transparent support platform material (Fig. 2) 5, which allows the model to be seen during the build process. The support material is then easily removed and the process is completed.

Claims

CLAIMS

1. A combined Light Emitting Diode (L.E.D.) and extrusion carriage used on 3 dimensional modelling machines.

2. A combined L.E.D. and extrusion carriage according to Claim 1, incorporates an array of light emitting diodes manufactured to a specific wavelength for instant curing and setting of ultra violet materials and is mercury free.

3. A combined L.E.D. and extrusion carriage according to Claim 1, automatically releases a specially formulated transparent material to provide a support platform for model overhangs.

4. A combined L.E.D. and extrusion carriage according to Claim 3, allows the model to be seen during build time.