Door hinge and method of manufacturing same

Patent metadata

Field	Value
Publication number	US-2020181961-A1
Application number	US-201916520125-A
Country	US
Kind code	A1
Filing date	Jul 23, 2019
Priority date	Dec 10, 2018
Publication date	Jun 11, 2020
Grant date	—

Abstract

A method of manufacturing a door hinge, which can improve productivity by applying both metal injection molding and additive manufacturing is disclosed. The door hinge includes: a first body configured to include at least one first connection member in which a first pinhole is formed; a second body configured to include at least one second connection member in which a second pinhole communicating with the first pinhole is formed; and a pin member configured to be added and filled in a cavity formed by communicating the first pinhole of the first body and the second pinhole of the second body with each other so that the first body and the second body are foldably connected to each other.

First claim

What is claimed is:

1 . A door hinge comprising:
a first body comprising at least one first connection member in which a first pinhole is formed; a second body comprising at least one second connection member in which a second pinhole communicating with the first pinhole is formed; and a pin member added and filled in a cavity formed by communicating the first pinhole of the first body and the second pinhole of the second body with each other so that the first body and the second body are foldably connected to each other.

2 . The door hinge of claim 1 , wherein the first body and the second body are formed in a metal injection molding method, and the pin member is formed in an additive manufacturing method.

3 . The door hinge of claim 2 , wherein the first body, the second body, and the pin member are formed by molding a mixture of a Fe—Ni—C-based metal powder and a binder, and then sintering the molded mixture.

4 . The door hinge of claim 3 , wherein the first body, the second body, and the pin member have a tensile strength of 500 MPa or more and an elongation of 15% or more after sintering.

5 . The door hinge of claim 1 , wherein the pinhole disposed at the lowermost end, which is either the first pinhole or the second pinhole, is closed in a lower end portion thereof.

6 . The door hinge of claim 5 , wherein the pinhole disposed at the lowermost end, which is either the first pinhole or the second pinhole, forms an enlarged region whose lower end portion has a larger volume than other regions thereof.

7 . A method of manufacturing a door hinge, comprising:
preparing a first mixture of a first metal powder and a first binder and a second mixture of a second metal powder and a second binder; molding the first mixture into a first body including at least one first connection member in which a first pinhole is formed; molding the first mixture into a second body including at least one second connection member in which a second pinhole configured to communicate with the first pinhole is formed; arranging the first body and the second body to align the first pinhole and the second pinhole along an axis such that the first pinhole and the second pinhole form a cavity; forming a pin member with the second mixture in the cavity by adding up droplets of the second mixture in the cavity; and sintering the first body, the second body, and the pin member.

8 . The method of manufacturing a door hinge of claim 7 ,
wherein the first body and the second body are molded in a metal injection molding method, and wherein the pin member is formed in an additive manufacturing method.

9 . The method of manufacturing a door hinge of claim 7 , wherein the first body and the second body are molded together in a single mold.

10 . The method of manufacturing a door hinge of claim 9 , wherein a temperature of the mold for molding the first body and the second body is maintained at 20° C. to 40° C.

11 . The method of manufacturing a door hinge of claim 7 , wherein a temperature of the mold for molding the first body and the second body is maintained at 20° C. to 40° C.

12 . The method of manufacturing a door hinge of claim 7 , wherein forming the pin member comprises cooling the second mixture while adding up the droplets of the second mixture in the cavity of which a temperature is 20° C. to 40° C., whereas a temperature of the second mixture is maintained at 90° C. to 100° C.

13 . The method of manufacturing a door hinge of claim 7 , wherein the pin member is formed while reaction with oxygen is blocked by injection of an inert gas.

14 . The method of manufacturing a door hinge of claim 7 , further comprising:
removing residues of the first mixture from the first body and the second body after molding the first body and the second body.

15 . The method of manufacturing a door hinge of claim 7 , further comprising:
removing residues of the first and second mixtures from the first body, the second body, and the pin member after forming the pin member.

16 . The method of manufacturing a door hinge of claim 7 , wherein the second mixture has a contraction ratio greater than that of the first mixture during sintering.

17 . The method of manufacturing a door hinge of claim 7 , wherein the first mixture and the second mixture are the same material.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Lee Jin Hyeon
• Jo Yeong Cheol
• Kwak Hyung Seok

Classifications

• E05D3/02 Primary

  with one pin · CPC title

• B22F3/225 Primary

  by injection molding · CPC title

• B22F12/86

  Serial processing with multiple devices grouped · CPC title

• B22F10/32

  of the atmosphere, e.g. composition or pressure in a building chamber · CPC title

• B22F10/14

  by jetting of binder onto a bed of metal powder · CPC title