Method and system for layerwise production of a tangible object

Abstract

A method cycle of a method for layerwise production of a tangible object (5) comprises the steps of: —solidifying a predetermined area of a layer (10) of a liquid (3) when said liquid layer (10) is adjoining a construction shape, so as to obtain a solid layer (14) of the tangible object (5); —separating said solid layer from said construction shape; and —moving, relative to one another, the separated solid layer and the construction shape to a predetermined position relative to one another for carrying out a successive such method cycle, so as to obtain a successive such solid layer adhered to the solid layer. For at least one of said method cycles, said solidifying and said separating are carried out such that solidifying of certain parts of the layer (14) takes place simultaneously with separating of other, already solidified parts of the layer.

Description

FIELD AND BACKGROUND OF THE INVENTION[0001]The invention relates to a method for layerwise production of a tangible object according to the preamble of claim 1. The invention also relates to a system for layerwise production of a tangible object.[0002]Such a method is known. For example it is known from DE10256672A1 that the liquid reservoir has a transparent bottom plate whose upper side has a separation layer. In the space above the bottom plate there is a carrier plate which can be moved up and down. During its movement, the carrier plate can reach positions ranging from under the liquid level to above it. A firstly formed solid layer of the tangible object is adhered to the underside of the carrier plate by selectively solidifying the liquid. Consecutively formed solid layers are each adhered to a previously formed solid layer, respectively.[0003]Each time after solidification of a new layer, the carrier plate together with the earlier solidified layers adhered thereon are moved...

AI Technical Summary

Benefits of technology

[0009]At first, the simultaneous solidifying and separating provides a speed gain of the process in itself. That is, the start of separating a layer does not have to wait until all parts of the layer have been solidified. Hence, there is little or no downtime of the separating means. Also, there is little or no downtime of the solidifying means.

[0010]Secondly, the separating of the layer is carried out more gradually in that it is performed part by part, instead of the whole layer at once. This means that, as compared to known methods, external forces to be exerted for the separation movement, and therefore the internal stresses in the tangible object, do not need to be that high anymore for a given separation speed. In fact, such external forces can be increased relative to known methods, without violating a maximum permissible internal stress level in the tangible object. In this respect, a further gain in production speed can be obtained.

Problems solved by technology

A drawback of the known method is, that during each method cycle the time required for said separation and for the liquid to flow-in between the separated solid layer and the separation layer of the bottom plate is relatively long.

This restricts the speed of the production process.

Note that this restriction in production speed is especially severe for objects having strongly varying cross-sections.

This external force results in an increase of internal stresses in the tangible object being produced.

If these stresses become too high, the object can deform, deteriorate or break.

Hence, for the known method, the maximum permissible internal stress level in the tangible object restricts the maximum permissible level of external forces to be applied, and hence restricts the production speed.

Since vertical tensile stresses in objects with varying cross-sections can become locally very high, the restriction in production speed is especially severe for such objects.

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