Search

JP-2026075248-A - Powder conveying equipment, machine tools, and screws

JP2026075248AJP 2026075248 AJP2026075248 AJP 2026075248AJP-2026075248-A

Abstract

[Problem] To provide a powder conveying device, machine tool, and screw capable of preventing cold welding of powders. [Solution] The powder conveying device comprises a screw (300) having a first threaded portion (310) and rotatable around a rotating shaft (201), and a housing (210) that houses the screw (300). The housing (210) is provided with a first powder supply port (221) and a powder discharge port (231). The first threaded portion (310) includes a first threaded region (311) located between the first powder supply port (221) and the powder discharge port (231) in the axial direction of the rotating shaft (201), where the threads constituting the first threaded portion (310) extend continuously, and a second threaded region (312) located on the opposite side of the powder discharge port (231) with the first powder supply port (221) in between, in the axial direction of the rotating shaft (201), where the threads constituting the first threaded portion (310) extend intermittently. [Selection Diagram] Figure 3

Inventors

  • 大多和 毅
  • 山崎 慶一
  • 石元 宏幸
  • 米澤 峻
  • 須藤 三樹大

Assignees

  • ＤＭＧ森精機株式会社

Dates

Publication Date
20260508
Application Date
20241022

Claims (8)

  1. A screw having a first threaded portion and capable of conveying powder by rotating around a rotation axis, The system comprises a housing for the aforementioned screw, The aforementioned housing includes, A first powder supply port for supplying powder toward the first screw portion, A powder discharge port is provided, located at a position offset in the direction of the rotation axis from the first powder supply port, for discharging the powder conveyed by the screw. The first threaded portion is, In the rotation axis direction, a first thread region is located between the first powder supply port and the powder discharge port, and the threads constituting the first thread portion extend continuously around the rotation axis, A powder conveying device that includes a second threaded region located on the opposite side of the powder discharge port, with the first powder supply port in the direction of the rotation axis, and in which the threads constituting the first threaded portion extend intermittently around the rotation axis.
  2. The screw further has a second threaded portion which is the opposite thread to the first threaded portion, The powder conveying device according to claim 1, wherein the housing is further provided with a second powder supply port, which is located on the opposite side of the first powder supply port in the rotation axis direction, straddling the powder discharge port, and for supplying powder toward the second screw portion.
  3. The aforementioned second threaded portion is, In the rotation axis direction, a third thread region is located between the second powder supply port and the powder discharge port, and the threads constituting the second thread portion extend continuously around the rotation axis, The powder conveying device according to claim 2, further comprising a fourth threaded region located on the opposite side of the powder discharge port, with the second powder supply port in the direction of the rotation axis, wherein the threads constituting the second threaded portion extend intermittently around the rotation axis.
  4. The tank further comprises a bottom surface that opens directly above the housing and sides that rise from the bottom surface, and a space for storing powder is formed on the bottom surface and at a position surrounded by the sides. The aforementioned side surface includes a first side surface portion and a second side surface portion facing the first side surface portion in the direction of the rotation axis, wherein the angle made by the first side surface portion with respect to the vertical direction is greater than the angle made by the second side surface portion with respect to the vertical direction. The powder conveying device according to claim 1, wherein, when viewed from above, the first powder supply port is positioned closer to the first side surface than the second side surface in the direction of the rotation axis.
  5. A tank positioned above the screw for storing the powder to be supplied to the first powder supply port, A powder conveying unit having the aforementioned screw and conveying powder from the tank, A pipe is positioned below the screw through which the powder from the powder discharge port flows, The powder conveying apparatus according to claim 1, further comprising a powder delivery unit located below the aforementioned piping, which mixes the powder from the piping with gas and delivers it.
  6. The powder conveying apparatus according to claim 1, A machine tool comprising a machine tool body that performs additional processing on a workpiece using powder conveyed by the aforementioned powder conveying device.
  7. A screw capable of conveying powder by rotating around a rotation axis, The first threaded portion and The first threaded portion is a reverse thread, and the device comprises a second threaded portion located at a position offset from the first threaded portion in the direction of the rotation axis, The first threaded portion is, The threads constituting the first thread portion extend continuously around the axis of rotation in a first thread region, In the rotation axis direction, the second screw region is located on the opposite side of the first screw region, with the first screw region in between, and the threads constituting the first screw region extend intermittently around the rotation axis. The aforementioned second threaded portion is, The threads constituting the second threaded portion extend continuously around the axis of rotation in a third threaded region, A screw comprising, in the direction of the rotation axis, a fourth threaded region located on the opposite side of the first threaded portion, with the third threaded region in between, and in which the threads constituting the second threaded portion extend intermittently around the rotation axis.
  8. A screw capable of conveying powder by rotating around a pivot axis, The system comprises a housing for the aforementioned screw, The aforementioned housing includes, A powder supply port for supplying powder toward the screw, A powder discharge port is provided, located at a position offset in the direction of the rotation axis from the powder supply port, for discharging the powder conveyed by the screw. The housing has an inner wall facing the screw in the radial direction of the rotation axis, through which the powder supply port opens. A powder conveying device, wherein the housing is provided with a recess on the inner wall that is recessed toward the radially outward direction of the rotation axis, on the opposite side of the powder discharge port from the powder supply port in the rotation axis direction.

Description

This invention relates to a powder conveying device, a machine tool, and a screw. For example, Japanese Patent Publication No. 2024-3370 (Patent Document 1) discloses a powder bed type three-dimensional additive manufacturing apparatus. The three-dimensional additive manufacturing apparatus has a powder supply device for supplying powder to the upper part of the table in the chamber. Japanese Patent Publication No. 2024-3370 This is a perspective view showing a machine tool equipped with a powder conveying device according to Embodiment 1 of the present invention.This is a front view showing the powder conveying device in Figure 1.This is a cross-sectional view partially showing the powder conveying device in Figure 2.This figure shows the screw in Figure 3.This is a cross-sectional view of the powder conveying device as seen in the direction of the arrow along the line V-V in Figure 2.This is a cross-sectional view showing the powder conveying device in Figure 3.This is a cross-sectional view showing a powder conveying device according to Embodiment 2 of the present invention. Embodiments of this invention will be described with reference to the drawings. In the drawings referred to below, identical or equivalent components are given the same number. (Embodiment 1) Figure 1 is a perspective view showing a machine tool equipped with a powder conveying device according to Embodiment 1 of the present invention. Referring to Figure 1, the powder conveying device 100 in this embodiment is used in a machine tool 10. The machine tool 10 is an additive manufacturing (AM) machine capable of additive processing. The machine tool 10 employs a powder bed system, where metal powder is spread on a table, and a laser is irradiated onto the powder to melt and solidify the required parts. The machine tool 10 comprises a machine tool body 21 and a powder conveying device 100. The machine tool body 21 is the main body of the machine tool 10 and performs additional machining. The machine tool body 21 includes a cover 31, a door 33, a processing chamber 50, a table (not shown) placed in the processing chamber 50 and covered with powder, and a laser irradiation device (not shown) that irradiates the powder on the table with a laser. The cover body 31 encloses the processing chamber 50 and forms the exterior of the machine tool 10. The processing chamber 50, together with the door 33, partitions the space where additional processing is performed. The processing chamber 50 is filled with an inert gas such as argon to prevent oxidation of the powder. The door 33 is mounted to the machining chamber 50 so as to be rotatable around a pivot axis extending vertically. The rotation of the door 33 separates the machining chamber 50 from the outside space or opens it to the outside space. Figure 2 is a front view showing the powder conveying device in Figure 1. Referring to Figures 1 and 2, the powder conveying device 100 conveys the powder used for additive machining in the machine tool body 21. The powder conveying device 100 is located outside the machining chamber 50. The cover body 31 partitions the containment space 60. The powder conveying device 100 is housed within the containment space 60. The powder conveying device 100 includes a tank 110, a powder conveying section 130, piping 140, and a powder discharge section 150. The tank 110 stores powder. The tank 110 has a bottom surface 121, a side surface 126, and a top surface 128. An opening 122 is provided in the bottom surface 121. The side surface 126 rises from the opening edge of the opening 122 in the bottom surface 121. A storage space 116 for storing powder is formed on the opening surface of the opening 122 in the bottom surface 121, at a position surrounded by the side surface 126. The top surface 128 faces the opening surface of the opening 122 in the vertical direction. The top surface 128 is connected to the upper end of the side surface 126. The tank 110 is equipped with a powder recovery port 111 and a powder replenishment port 112. The powder recovery port 111 and the powder replenishment port 112 open to the top surface 128 and communicate with the storage space 116. Powder not used in the additive machining process in the machine tool body 21 is transported from the machining chamber 50 towards the powder conveying device 100 and recovered into the storage space 116 through the powder recovery port 111. If the amount of powder stored in the storage space 116 becomes insufficient, new powder is replenished into the storage space 116 through the powder replenishment port 112. The powder conveying unit 130 conveys powder from the tank 110. The powder conveying unit 130 conveys the powder stored in the tank 110 toward the piping 140 and powder discharge unit 150, which will be described later. The powder conveying unit 130 is located below the tank 110. The bottom surface 121 of the tank 110 is connected to the top of the powder conveying unit 130. Powder flows throug