Three-dimensional printing apparatus

Patent metadata

Field	Value
Publication number	US-9833952-B2
Application number	US-201514837073-A
Country	US
Kind code	B2
Filing date	Aug 27, 2015
Priority date	Aug 28, 2014
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

A three-dimensional printing apparatus that forms a three-dimensional object using cross-sectional shapes of the object includes a controller that is configured or programmed to include a dividing unit that divides a cross-sectional shape into a plurality of blocks, a shape determining unit that determines whether one of the blocks has a predetermined shape and defines the block having the predetermined shape as a characteristic block, a count determining unit that determines whether the proportion of the number of the characteristic blocks to the total number of the blocks is equal to or greater than a predetermined proportion, and a light application unit that sets the energy of light from a light source to a first energy or to a second energy being lower than the first energy depending on the proportion, when applying the light to a photocurable resin in a region corresponding to the characteristic blocks.

First claim

What is claimed is:

1. A three-dimensional printing apparatus that forms a three-dimensional object by preparing cross-sectional shapes of the three-dimensional object and successively stacking resin layers with corresponding shapes to the cross-sectional shapes, each of the layers formed by curing a liquid photocurable resin, the three-dimensional printing apparatus comprising:
a vat made of a resin and accommodating the photocurable resin;
a lighting device disposed below the vat and including a light source emitting light, the lighting device applying the light from the light source to the photocurable resin in the vat; and
a controller controlling the lighting device; wherein
the controller is programmed to include:
a dividing unit that divides at least one of the cross-sectional shapes into a plurality of blocks;
a divided block calculating unit that counts a total number of the plurality of blocks divided by the dividing unit;
a shape determining unit that determines whether or not each one of the plurality of blocks divided by the dividing unit has a predetermined shape and that defines at least one of the plurality of blocks that has been determined to have the predetermined shape as a characteristic block;
a counting unit that counts a number of the characteristic blocks;
a count determining unit that determines whether or not a proportion of the number of the characteristic blocks counted by the counting unit to the total number of the plurality of blocks counted by the divided block calculating unit is equal to or greater than a predetermined proportion; and
a light application unit that sets an energy of the light from the light source to a first energy at least when applying the light to the photocurable resin in a region corresponding to the characteristic blocks if the proportion is determined by the count determining unit to be less than the predetermined proportion, and that sets the energy of the light from the light source to a second energy being lower than the first energy at least when applying the light to the photocurable resin in the region corresponding to the characteristic blocks if the proportion is determined by the count determining unit to be equal to or greater than the predetermined proportion.

2. The three-dimensional printing apparatus according to claim 1 , wherein the light application unit sets the energy of the light from the light source to the second energy when applying the light to the photocurable resin in a region corresponding to the at least one cross-sectional shape, if the proportion of the number of the characteristic blocks to the total number of the plurality of blocks is determined by the count determining unit to be equal to or greater than the predetermined proportion.

3. The three-dimensional printing apparatus according to claim 1 , wherein
the dividing unit is programmed to include:
an extracting unit that extracts a connecting point of adjacent line segments of a contour of the at least one cross-sectional shape as a characteristic point if an interior angle defined by the adjacent line segments is equal to or greater than about 270 degrees; and
a shape dividing unit that, when the extracting unit extracts a plurality of the characteristic points and when a connecting line that connects two adjacent ones of the characteristic points to each other on the contour of the at least one cross-sectional shape is within a region of the at least one cross-sectional shape, divides the at least one cross-sectional shape at the connecting line to divide the at least one cross-sectional shape into the plurality of blocks.

4. The three-dimensional printing apparatus according to claim 3 , wherein the shape determining unit is programmed to include an area determining unit that determines one of the plurality of blocks to be the characteristic block if the proportion of the area of the one of the plurality of blocks to the area of a target region of the light source is equal to or less than a predetermined proportion.

5. The three-dimensional printing apparatus according to claim 3 , wherein the shape determining unit is programmed to include an interior angle determining unit that determines one of the plurality of blocks to be the characteristic block if, among interior angles at vertices of the one of the plurality of blocks that are not at the characteristic points, a smallest one of the interior angles is an acute angle.

6. The three-dimensional printing apparatus according to claim 3 , wherein the shape determining unit is programmed to include a spacing determining unit that determines one of the plurality of blocks to be the characteristic block if the one of the plurality of blocks and an adjacent one of the plurality of blocks are spaced apart from each other and a spacing distance therebetween is equal to or less than a predetermined distance.

7. A three-dimensional printing apparatus that forms a three-dimensional object by preparing cross-sectional shapes of the three-dimensional object and successively stacking resin layers with corresponding shapes to the cross-sectional shapes, each of the layers formed by curing a liquid photocurable resin, the three-dimensional printing apparatus comprising:
a vat made of a resin and accommodating the photocurable resin;
a lighting device disposed below the vat and including a light source emitting light, the lighting device applying the light from the light source to the photocurable resin in the vat; and
a controller controlling the lighting device; wherein
the controller is programmed to include:
a dividing unit that divides at least one of the cross-sectional shapes into a plurality of blocks;
a divided block calculating unit that counts a total number of the plurality of blocks divided by the dividing unit;
a shape determining unit that determines whether or not each one of the plurality of blocks divided by the dividing unit has a predetermined shape and that defines at least one of the plurality of blocks that has been determined to have the predetermined shape as a characteristic block;
a counting unit that counts a number of the characteristic blocks;
a count determining unit that determines whether or not the number of the characteristic blocks counted by the counting unit is equal to or greater than a predetermined number; and

a light application unit that sets an energy of the light from the light source to a first energy at least when applying the light to the photocurable resin in a region corresponding to the characteristic blocks if the number of the characteristic blocks is determined by the count determining unit to be less than the predetermined number, and that sets the energy of the light from the light source to a second energy being lower than the first energy at least when applying the light to the photocurable resin in the region corresponding to the characteristic blocks if the number of the characteristic blocks is determined by the count determining unit to be equal to or greater than the predetermined number.

8. The three-dimensional printing apparatus according to claim 7 , wherein the light application unit sets the energy of the light from the light source to the second energy when applying the light to the photocurable resin in the region corresponding to the at least one cross-sectional shape, if the number of the characteristic blocks is determined by the count determining unit to be equal to or greater than the predetermined number.

9. The three-dimensional printing apparatus according to claim 7 , wherein
the dividing unit is programmed to include:
an extracting unit that extracts a connecting point of adjacent line segments of a contour of the at least one cross-sectional shape as a ch

Assignees

• Roland Dg Corp

Inventors

• Kobayashi Kouichi

Classifications

• B29C64/393

  for controlling or regulating additive manufacturing processes · CPC title

• B33Y50/02

  for controlling or regulating additive manufacturing processes · CPC title

• B29K2105/0058

  Liquid or visquous · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B29K2105/0002

  monomers or prepolymers · CPC title