Method and workpiece with an interior angle formed by alternating printing techniques

Abstract

A method for producing a workpiece that is constructed layer-by-layer, and a workpiece that is constructed layer-by layer. The workpiece has a contour acting as an interior angle. Alternating undercuts are provided along a curve at which the surfaces that form the contour which acts as an interior angle intersect. The undercuts are formed in consecutive layers of the workpiece that is constructed layer-by-layer on different sides of the curve.

Claims

1. A method of producing a workpiece, the method comprising: building up the workpiece layer-by-layer in alternating layers and forming the workpiece with at least one contour defining an interior angle, the contour having a curve at which faces spanned by the contour intersect; forming undercuts at the curve at which the faces intersect in alternatingly successive layers of the workpiece on mutually different sides of the curve.

2. The method according to claim 1, which comprises building up the workpiece in a material extrusion method.

3. The method according to claim 1, wherein the faces spanned by the contour defining the interior angle enclose an angle of less than 180°.

4. The method according to claim 1, which comprises producing a layer from one or more material layers that are applied in succession and connected to one another.

5. A computer program product for carrying out the method according to claim 1.

6. A workpiece, comprising: a workpiece structure built up layer-by-layer with a plurality of layers and having at least one contour forming an interior angle; wherein faces which are spanned by the contour forming the interior angle and which enclose the interior angle intersect in a curve; and wherein successive layers of said plurality of layers are formed with undercuts along said curve in alternating successive layers of said workpiece structure, and said undercuts are alternatingly formed on different sides of said curve.

7. The workpiece according to claim 6, wherein said workpiece structure is formed by building up the workpiece layer-by-layer in alternating layers to thereby form the workpiece with at least one contour defining an interior angle, wherein the contour has a curve at which faces spanned by the contour intersect, and wherein the alternating layers are formed with undercuts at the curve at which the faces intersect in alternatingly successive layers of the workpiece on mutually different sides of the curve.

8. The workpiece according to claim 6, wherein said faces spanned by said contour forming the interior angle enclose an angle of less than 180°.

9. The workpiece according to claim 6, wherein a layer of said plurality of layers comprises one material layer or a plurality of material layers which are applied in succession and connected to one another.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows a cross section through an ideal-typical workpiece with an interior angle for abutment of an assembly partner,

(2) FIG. 2 shows a cross section through a workpiece with a rounded, non-sharp contour provided as an interior angle,

(3) FIG. 3 shows a cross section through a workpiece with an interior angle and a corner undercut,

(4) FIG. 4 schematically shows a three-dimensional, perspective view of a workpiece produced in accordance with the invention,

(5) FIG. 5 shows a cross section through a workpiece according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

(6) In FIG. 1, an ideal-typical workpiece 1 with an interior angle α, suitable for abutment of an assembly partner, is illustrated in cross section. The interior angle α is enclosed by two delimiting faces 12 and 13 of the workpiece 1 which intersect along an inner edge 11. Here, the angle width of said interior angle is 90° and it is sharp, i.e. the delimiting faces 12 and 13 intersect along the inner edge 11. Since this is a cross-sectional illustration, the inner edge 11 is depicted at a point of an inside corner—the vertex of the interior angle α. The delimiting faces 12 and 13 are correspondingly drawn as lines—the legs of the interior angle α.

(7) Here, the delimiting faces 12 and 13 are uninterrupted, planar surfaces of the workpiece 1. They serve for the abutment of an, in particular right-angled, assembly partner, which is not outlined in any more detail in this image. Interior angle and contacting faces of the assembly partner are designed to be complementary to one another. The assembly partner may be of cuboidal design, for example. The target contour profile of the interior angle α is correspondingly adapted.

(8) In additive manufacturing (especially in the FDM method), it is not possible to produce “sharp” interior angles. Additive manufacturing of such a geometry results in a rounding of the contour serving as interior angle, as is schematically depicted in FIG. 2. The planar delimiting faces 12 and 13 are connected to one another via a portion 14 which is in the form of a partial tube and which is depicted as a circular arc in the two-dimensional sectional illustration.

(9) Contours acting as an interior angle and having a corner undercut can also be realized technically. FIG. 3 shows such a workpiece 1. An assembly partner 16 has been placed against the delimiting faces 12 and 13. The lateral faces 9 and 10 of said assembly partner contact the delimiting faces 12 and 13. Said assembly partner projects into a corner undercut 15 in the workpiece. As a result, the delimiting faces 12 and 13 have been reduced considerably in relation to the workpiece from FIG. 1.

(10) There are then applications in which a rounding (as per FIG. 2) is not permissible and a conventional corner undercut (as per FIG. 3) would lead to an excessive reduction of the abutment face for an assembly partner.

(11) If a rounded contour serving as an interior angle, as in FIG. 2, is accessible for postprocessing, this problem could be solved by way of subsequent, for example material-removing, postprocessing. However, this would be associated with considerable additional effort and thus with additional costs.

(12) Instead of this, the invention now proposes a production method for a workpiece which is built up layer-by-layer and which has at least one contour acting as an interior angle, according to which method, along a curve in which faces that are spanned by the contour acting as an interior angle and that enclose the interior angle intersect, undercuts are alternatingly provided in successive layers of the workpiece, which is built up layer-by-layer, on different sides of the curve.

(13) A workpiece 1 produced in this way is illustrated in a perspective view in FIG. 4. Analogously to FIG. 1 to FIG. 3, FIG. 5 in turn shows a cross section through the workpiece according to the invention of FIG. 4, with non-visible edges [drawn in dashed and dotted form] and an assembly partner 16, which is designed to be complementary to the contour acting as an interior angle and faces spanned by said contour, with its lateral faces 9 and 10. Both figures are described together below.

(14) The workpiece 1 has a contour acting as an interior angle α. The interior angle α is in this case enclosed by two faces 2 and 3 which are spanned by the contour, which acts as an interior angle α, of the workpiece 1. The faces 2 and 3 intersect in a curve 4, in particular a straight line.

(15) The surfaces of the workpiece in the region of the interior angle α have on both sides undercuts 7 and 8, which are alternatingly arranged in the opposite surfaces.

(16) The delimiting faces 5 and 6, which belong to the surface of the workpiece and delimit the contour acting as an interior angle α, of the webs of the workpiece 1, said webs remaining between the undercuts 7 and 8, are used as abutment faces of the workpiece 1 for the assembly partner 16 which is designed to be complementary to the contour acting as an interior angle.

(17) The widths of the webs and thus of the delimiting faces 5 and 6 and of the undercuts 7 and 8 are the same here and identical to the width of a layer of the workpiece which is built up layer-by-layer. Thus, the reference designations 5, 6, 7 and 8 hereby simultaneously denote layers of the workpiece which is built up layer-by-layer.

(18) The delimiting faces 5 contact the respectively adjacent delimiting faces 6 on one side at a point or on both sides at a respective point on a side. These contact points lie in the curve 4. The undercuts 7 and 8 are thus provided, along the curve 4, alternatingly in adjacent, successive layers of the workpiece, which is built up layer-by-layer, on different sides of the curve 4.

(19) All points of the delimiting face 5 lie in the imaginary face 2 spanned by it. Equally, all points of the delimiting face 6 lie in the imaginary face 3 spanned by it. On account of the particular embodiment of the workpiece 1 illustrated here, with the curve 4 embodied as a straight line, the workpiece 1 in plan view appears identical to the workpiece from FIG. 1. In the projection in a plane perpendicular to the curve 4 embodied as a straight line, a sharp interior angle is obtained.

(20) The contour of the workpiece 1 thus acts as a sharp interior angle without a rounding and without a conventional corner undercut.