ADDITIVE MANUFACTURING APPARATUS AND ADDITIVE MANUFACTURING METHOD
FIG18 is a view for explaining control in the additive manufacturing apparatus according to a fourth embodiment of the present invention  FIG19 is a view for explaining building of a deposit by the additive manufacturing apparatus according to a fifth embodiment of the present invention  FIG17 is a view for explaining correction to parameters in the additive manufacturing apparatus according to a third embodiment of the present invention
FIG18 is a view for explaining control in the additive manufacturing apparatus 1 according to a fourth embodiment of the present invention. In the fourth embodiment, a temperature of the substrate 2 or the first bead is measured, and building is stopped or conditions are changed on the basis of the measured temperature. In the fourth embodiment, the same components as those in the first to third embodiments are denoted by the same reference numerals, and a difference of the fourth embodiment from the first to third embodiments will mainly be described. In the fourth embodiment, the measurement device 17 includes a temperature sensor. The temperature sensor is a laser device such as a non-contact pyrometer. The measurement device 17 measures a temperature LTR of the substrate 2 when the bead 22-1 as the first bead is formed. The measurement device 17 measures the temperature LTR of the first bead when the second bead is formed. FIG18 illustrates the temperature LTR of the substrate 2 and the temperature LTR of the bead 22-1 as the first bead when the bead 22-2 as the second bead is formed. The arithmetic device 4 compares a temperature LT stored in the database with the temperature LTR. In a case where a step of stacking the second bead on the first bead is performed successively, LTR becomes approximately equal to LT.  FIG19 is a view for explaining building of a deposit by the additive manufacturing apparatus 1 according to a fifth embodiment of the present invention. In the fifth embodiment, the additive manufacturing apparatus 1 builds a lid-like deposit 32 on a cylindrical structure 31 by forming the bead 22 along a circle while gradually decreasing the diameter of the circle. In the fifth embodiment, the same components as those in the first to fourth embodiments are denoted by the same reference numerals, and a difference from the first to fourth embodiments will mainly be described.  FIG17 is a view for explaining correction to parameters in the additive manufacturing apparatus 1 according to the third embodiment of the present invention. In the third embodiment, the measurement device 17 measures a value BHR of the height BH of the bead 22 or a value BTR of a stacking height of the bead 22 from the substrate 2. On the basis of the measured value BHR or the measured value BTR, the pitch KP is corrected. In the third embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and a difference of the third embodiment from the first and second embodiments will mainly be described. FIG17 illustrates the measured value BHR of the bead 22-1 and the measured value BTR of the bead 22-3. When BH>BHR holds, the arithmetic device 4 corrects the pitch KP stored in the database, to KP'=KP+(BH-BHR)×γ. Alternatively, when the sum of the heights BH of the beads 22-1, 22-2 and 22-3 is expressed by BH+BHn and BTR>BH+BHn holds, the arithmetic device 4 corrects the pitch KP stored in the database, to KP'=KP+(BH+BHn-BTR)×δ. γ and δ are numerical values of 1 or more and 2 or less and are arbitrarily set numerical values. The arithmetic device 4 stores, in the database, the corrected pitch KP', and γ and δ set in calculating the pitch KP'.
view
22
bead beads
2
substrate
20
laser beam
21
tip
31
structure
32
deposit
['1. An additive manufacturing apparatus (1) for building a deposit on a substrate (2), the apparatus comprising: a feeding unit (6, 8) to feed a build material (7) to a feeding position; an irradiation unit (10, 11, 12) to irradiate the feeding position with a laser beam that melts the build material; a control unit (3) to perform control for building the deposit by stacking beads formed by movement of the feeding position with respect to the substrate and melting of the build material; and an arithmetic unit (4) to execute an arithmetic process of computing parameters for the control unit to perform the control, wherein the beads include two beads (22-1, 22-2) stacked on each other, the two beads are a first bead (22-1) and a second bead (22-2) stacked on the first bead, the first bead being formed earlier than the second bead, the feeding position being a first position (C1) in formation of the first bead, the feeding positon being a second position (C2) in formation of the second bead,  characterized in that  the arithmetic unit calculates an interval (KS) between the first position and the second position in a set direction on a basis of a width (BW) of the first bead and a diameter (LD) of the laser beam, the set direction being a direction of the width of the first bead, and the control unit performs control for setting the second position to a position shifted from the first position in the set direction by the interval, so as to allow a part of the second bead to protrude from the first bead in the set direction.', '8. The additive manufacturing method according to claim 7, comprising: a step of building a first deposit by stacking the beads when the set direction is a first set direction (A); a step of building a second deposit extending toward the first deposit by stacking the beads when the set direction is a second set direction (B); and a step of building a single structure by connecting the first deposit and the second deposit above the substrate.']