Self-lubricating pin

Patent metadata

Field	Value
Publication number	US-12454979-B2
Application number	US-202217934768-A
Country	US
Kind code	B2
Filing date	Sep 23, 2022
Priority date	Sep 23, 2022
Publication date	Oct 28, 2025
Grant date	Oct 28, 2025

Abstract

A pin for a pinned joint includes a hollow body with a first and second end caps coupled to first and second ends, respectively. The body and the end caps at least partially define a cavity within the body, wherein at least one aperture extends through the hollow body. A main piston is slidably disposed within the cavity and divides the cavity into a first chamber proximate to the first end and a second chamber proximate to the second end and fluidly isolated from an environment around the body. A lubricant is disposed within the first chamber. The main piston moves toward the first end of the body when a pressure in the second chamber is greater than a pressure of the environment. Movement of the main piston toward the first end of the body discharges lubricant through the at least one aperture.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1 . A pin pivotably coupling a clevis arm to a lug of a second element, the pin comprising:
a hollow cylindrical body with a first end cap coupled to a first end of the body and a second end cap coupled to a second end of the body, the body and the first and second end caps at least partially defining a cavity within the body, one of the first and second ends including an annular flange extending radially therefrom for seating against a first clevis arm lug, the other of the first and second ends including external threads formed thereon for receiving a nut which abuts a second clevis arm lug, the pin extending through aligned apertures in the first and second clevis arm lugs and the lug of the second element disposed therebetween; a piston slidably disposed within the cavity and dividing the cavity into a first chamber proximate to the first end and a second chamber proximate to the second end, wherein at least one aperture extends through the body and is in fluid communication with the first chamber, and the second chamber is fluidly isolated from an environment around the body; a valve comprising a standard grease fitting mounted to an aperture formed in the first end cap and fixedly positioned relative to the body, wherein the valve is configured to selectively provide a path to fill the first chamber with lubricant; a seal mounted to an aperture formed in the second end cap and configured to be removed selectively to enable fluid communication between the second chamber and the environment around the body; and a lubricant disposed within the first chamber, wherein, when a pressure in the second chamber is greater than a pressure of the environment, the piston moves within the cavity toward the first end of the body, and wherein movement of the piston toward the first end of the body discharges lubricant through the at least one aperture.

2 . The pin of claim 1 , further comprising a stop configured to limit travel of the piston toward the first end of the body.

3 . The pin of claim 1 , wherein the seal isolates the second chamber from the environment.

4 . The pin of claim 1 , wherein the first chamber is configured to receive lubrication when the seal is removed.

5 . The pin of claim 4 , wherein the first chamber receiving lubrication when the seal is removed drives the piston toward the second end of the body.

6 . A landing gear assembly, comprising a pinned joint with the pin according to claim 1 .

7 . The landing gear assembly of claim 6 mounted to one of an aircraft or a maglev vehicle.

8 . A pin for a pinned joint comprising:
a hollow body with a first end cap coupled to a first end of the body and a second end cap coupled to a second end of the body, the body and the first and second end caps at least partially defining a first cavity within the body; a main piston slidably disposed within the first cavity and dividing the first cavity into a first chamber proximate to the first end and a second chamber proximate to the second end, wherein the first chamber is in fluid communication with an environment around the body through a first aperture, and the second chamber is fluidly isolated from the environment around the body; a housing disposed within the first chamber, the housing at least partially defining a second cavity; a secondary piston slidably disposed within the second cavity and sealingly engaging an inner surface of the housing to divide the second cavity into a first housing chamber and a second housing chamber, a second aperture extending through the housing and being in fluid communication with the first housing chamber; a rod coupled at a first end to the main piston and at a second end to the secondary piston; and a lubricant disposed within the first housing chamber, wherein movement of the main piston toward the first end of the body drives the secondary piston to discharge lubricant through the second aperture.

9 . The pin of claim 8 , further comprising a valve mounted to the first end cap and configured to selectively provide a path to fill the first housing chamber with lubricant.

10 . The pin of claim 9 , wherein the valve is in fluid communication with the second cavity.

11 . The pin of claim 8 , wherein a portion of the first chamber outside of the housing is in fluid communication with the environment.

12 . The pin of claim 8 , further comprising a one-way housing valve disposed within the housing and dividing the first housing chamber into a first chamber portion and a second chamber portion.

13 . The pin of claim 12 , wherein the first chamber portion is proximate to the first end cap.

14 . The pin of claim 12 , wherein the second aperture is in fluid communication with the second chamber portion.

15 . A landing gear assembly, comprising a pinned joint with the pin according to claim 8 .

16 . The landing gear assembly of claim 15 mounted to one of an aircraft or a maglev vehicle.

Assignees

• Safran Landing Systems
• Safran Landing Systems Canada Inc

Inventors

• Ellis Andrew Michael
• Gohil Aakash
• Klim Graeme Peter Arthur

Classifications

• Y10T403/32918

  fork and tongue · CPC title

• F16C11/045 Primary

  with at least a pair of arms pivoting relatively to at least one other arm, all arms being mounted on one pin (crank-pins F16C11/02) · CPC title

• Y10T403/32926

  with interposed antifriction means · CPC title

• B64C25/32

  characterised by elements which contact the ground or similar surface  (arrester hooks B64C25/68) · CPC title

• F16C2326/10

  Railway vehicles · CPC title