Two-stage sintering furnace and methods of operating thereof

Patent metadata

Field	Value
Publication number	US-2022016700-A1
Application number	US-202017436790-A
Country	US
Kind code	A1
Filing date	Mar 13, 2020
Priority date	Mar 15, 2019
Publication date	Jan 20, 2022
Grant date	—

Abstract

A sintering and debinding system includes a debinding chamber configured to switch between an open state and a closed state, the open state being configured to permit receipt or removal of at least one part within or from the debinding chamber and a sintering chamber operably connected to the debinding chamber and being vertically positioned above or below the debinding chamber. The sintering system also includes a shelf structure configured to receive the at least one part, the shelf structure being movable between the debinding chamber and the sintering chamber and a gate valve configured to switch between an open state and a closed state, the gate valve being configured to selectively permit or block fluid communication between the debinding chamber and the sintering chamber. The gate valve is configured such that: when the gate valve is in an open state, fluid communication between the debinding chamber and the sintering chamber is permitted and the shelf structure is movable between the debinding chamber and the sintering chamber. The gate valve is further configured such that, when the gate valve is in the closed state, fluid communication between the debinding chamber and sintering chamber is restricted, and at least one of: (i) movement of the shelf structure between the debinding chamber and the sintering chamber is restricted or (ii) the debinding chamber is configured to permit receipt within and removal of the at least one part from the debinding chamber.

First claim

What is claimed is:

1 . A sintering and debinding system, comprising:
a debinding chamber configured to switch between an open state and a closed state, the open state being configured to permit receipt or removal of at least one part within or from the debinding chamber; a sintering chamber operably connected to the debinding chamber and being vertically positioned above or below the debinding chamber; a shelf structure configured to receive the at least one part, the shelf structure being movable between the debinding chamber and the sintering chamber; and a gate valve configured to switch between an open state and a closed state, the gate valve being configured to selectively permit or block fluid communication between the debinding chamber and the sintering chamber, the gate valve being configured such that: when the gate valve is in the open state, fluid communication between the debinding chamber and the sintering chamber is permitted and the shelf structure is movable between the debinding chamber and the sintering chamber, and when the gate valve is in the closed state, fluid communication between the debinding chamber and the sintering chamber is restricted, and at least one of: (i) movement of the shelf structure between the debinding chamber and the sintering chamber is restricted or (ii) the debinding chamber is configured to permit receipt within and removal of the at least one part from the debinding chamber.

2 . The system of claim 1 , wherein the gate valve is configured to be in the closed state when generating heat during a debinding process so as to prevent communication of at least one of volatized binder from the at least one part or moisture from entering the sintering chamber such that, at the conclusion of the debinding process, a greater amount of volatized debinder is present in the debinding chamber as compared to the sintering chamber.

3 . The system of claim 1 , wherein when the gate valve is in the closed state, the debinding chamber is configured to be cleaned by heating an interior of the debinding chamber to a temperature of about 900 degrees centigrade or less.

4 . The system of claim 1 , wherein when the gate valve is in a closed state, the debinding chamber is configured to thermally debind the at least one part by heating an interior of the debinding chamber to a temperature of about 900 degrees centigrade or less.

5 . The system of claim 1 , wherein when the gate valve is in a closed state, the sintering chamber is configured to the at least one part to a temperature greater than about 1 , 000 degrees centigrade.

6 . The system of claim 1 , further comprising:
a cable configured to move the shelf structure between the debinding chamber and the sintering chamber.

7 . The system of claim 6 , wherein an end of the cable includes an enlarged end portion configured to be received by the shelf structure.

8 . The system of claim 1 , further comprising a loading gate configured to selectively permit access to the interior of the debinding chamber.

9 . The system of claim 1 , wherein the debinding chamber and the sintering chamber are connected to each other by a shared housing.

10 . The system of claim 1 , wherein the gate valve further comprises at least one curved plate.

11 . The system of claim 10 , wherein the at least one curved plate is movably positioned between the debinding chamber and the sintering chamber.

12 . A sintering and debinding method, comprising:
placing at least one part inside a debinding chamber, wherein the debinding chamber is operably connected to a sintering chamber; debinding the at least one part by raising a temperature within the debinding chamber to a debinding temperature while sealing the sintering chamber from the debinding chamber; transferring the at least one part from the debinding chamber to the sintering chamber while fluid communication is permitted between the sintering chamber and the debinding chamber; and sintering the at least one part within the sintering chamber.

13 . The method of claim 12 , wherein debinding includes closing a gate valve to seal the sintering chamber from the debinding chamber.

14 . The method of claim 12 , further including, after debinding, opening a gate valve to permit fluid communication between the sintering chamber and the debinding chamber.

15 . The method of claim 12 , further including moving a curved plate of a gate valve to either: (i) close the gate valve to seal the sintering chamber from the debinding chamber, or (ii) open the gate valve to permit fluid communication between the sintering chamber and the debinding chamber.

16 . The method of claim 12 , further including heating an interior of the debinding chamber to a temperature of about 900 degrees centigrade, or less.

17 . The method of claim 16 , further including heating an interior of the sintering chamber to a temperature greater than about 1 , 000 degrees centigrade.

18 . The method of claim 17 , further including transferring the at least one part from the debinding chamber to the sintering chamber after heating the interior of the debinding chamber and before heating the interior of the sintering chamber without removing the at least one part from a common housing of the debinding chamber and the sintering chamber.

19 . A sintering and debinding system, comprising:
a debinding chamber including a loading gate configured to switch between an open state and a closed state, the open state of the loading gate being configured to permit receipt or removal of at least one part from within the debinding chamber; a sintering chamber connected to the debinding chamber and positioned adjacent to the debinding chamber; and a gate valve configured to switch between an open state and a closed state, the gate valve being configured to regulate fluid communication between the debinding chamber and the sintering chamber, the gate valve configured such that: when the gate valve is in the open state, fluid communication is allowed between the debinding chamber and the sintering chamber and the at least one part is movable between the debinding chamber and the sintering chamber, and the loading gate is in the closed state, and when the gate valve is in the closed state in which fluid communication between the debinding chamber and the sintering chamber is restricted, at least one of: (i) movement of the at least one part between the debinding chamber and the sintering chamber is restricted or (ii) the loading gate is in the open position enabling receipt and removal of the at least one part from the debinding chamber.

20 . The system of claim 1 , wherein the gate valve is configured to be closed during a debinding process so as to prevent communication of at least one of volatized binder from the at least one part or moisture from entering the sintering chamber such that, at the conclusion of the debinding process, a greater amount of volatized debinder is present in the debinding chamber as compared to the sintering chamber.

Assignees

• Desktop Metal Inc

Inventors

• Woodard Nathan
• Fontana Richard Remo
• Weiss Robert Edward

Classifications

• B22F10/10

  Formation of a green body · CPC title

• B22F3/003 Primary

  Apparatus, e.g. furnaces (in general F27B) · CPC title

• F27B2017/0091

  Series of chambers, e.g. associated in their use · CPC title

• B22F3/1021

  Removal of binder or filler (removal of binder from ceramics C04B35/638) · CPC title

• Y02P10/25

  Process efficiency · CPC title