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EP-4386459-B1 - POSITIONAL LENS LOCKING

EP4386459B1EP 4386459 B1EP4386459 B1EP 4386459B1EP-4386459-B1

Inventors

  • DANICICH, JEFFREY P.
  • WICKS, Curtis J.

Dates

Publication Date
20260506
Application Date
20231121

Claims (14)

  1. A positional lens locking assembly (10) for focusing and maintaining focus of a camera lens assembly (12), the positional lens locking assembly comprising: a lens tube (24) having a head (26) and a barrel (28), wherein the head extends outward from the barrel and wherein the barrel has a threaded portion (30); a camera housing (14) having a first threaded bore (32) configured to receive the threaded portion of the barrel; a sealing member (16) disposed between the head and the camera housing, the sealing member configured to be compressed between the head and the camera housing; and a locking member (18) configured to retain the lens tube in a position; characterized in that the locking member (18) comprises a threaded fastener (36) configured to press a portion of the first threaded bore (32) of the camera housing (14) against the threaded portion (30) of the barrel (28).
  2. The positional lens locking assembly of claim 1, wherein the sealing member (16) is an O-ring, the O-ring disposed around the barrel.
  3. The positional lens locking assembly of claim 1, wherein the sealing member (16) comprises: a lens tube ring (40) disposed around the barrel (28) between the head (26) and the camera housing (14); a first O-ring (42) disposed between the head and the lens tube ring; and a second O-ring (44) disposed between the lens tube ring and the camera housing.
  4. The positional lens locking assembly of claim 3, wherein the lens tube ring (40) has a seating portion (50) and a retention portion (52), the seating portion extending perpendicular to and outward from the barrel (28) to the retention portion (52), the retention portion extending parallel to the barrel, wherein the first O-ring (42) is disposed between the retention portion and a first side of the seating portion and the second O-ring (44) is disposed between the retention portion and a second side of the seating portion.
  5. The positional lens locking assembly of claim 1, wherein the camera housing (14) comprises a second threaded bore (34) configured to receive the threaded fastener (36), the second threaded bore having an inner end disposed on a back side of the portion of first threaded bore (32) configured to be pressed against the threaded portion (30) of the barrel (28).
  6. The positional lens locking assembly of claim 5, wherein the second threaded bore (34) is oriented perpendicular to the first threaded bore (32).
  7. The positional lens locking assembly of claim 5 or 6, wherein the locking member (18) further comprises a threaded insert (38), the threaded insert disposed in the second threaded bore (34) and configured to receive the threaded fastener (36); optionally wherein the threaded insert (38) is a thread locking insert.
  8. The positional lens locking assembly of any of claims 5 to 7 and further comprising a plurality of locking members (18) and a corresponding plurality of second threaded bores (34), the plurality of locking members circumferentially spaced around the threaded barrel.
  9. The positional lens locking assembly of any of claims 3 or 4, wherein the first O-ring (42) is compressed between surfaces of the head (26) and the lens tube ring (40) and the second O-ring (44) is compressed between surfaces of the lens tube ring and the camera housing (14).
  10. The positional lens locking assembly of any of claims 3 to 9, wherein the sealing member (19) is sized to hold the lens tube (24) in tension during an operation of rotating the lens tube toward and away from an image sensor (22) to bring an image into focus.
  11. A method of focusing and locking a lens tube (24) of a camera assembly in position, the method comprising: rotating the lens tube (24) in a camera housing (14) toward or away from an image sensor (22) until an image is in focus, wherein the lens tube is in a position of focus when the image is in focus and wherein the lens tube is maintained in tension as the lens tube is rotated; and locking the lens tube (24) in the position of focus; wherein rotating the lens tube (24) comprises engaging threads of the lens tube with threads of a first bore (32) in a camera housing (14); and wherein locking the lens tube (24) in the position of focus comprises fixing the threads of the first bore (32) against threads of the lens tube, characterized in that fixing the threads of the first bore (32) against threads of the lens tube (24) comprises pressing the threads of the first bore against the threads of the lens tube by applying a force, with a threaded fastener (36), against a back side of the first bore (32).
  12. The method of claim 11, wherein rotating the lens tube (24) further comprises engaging a sealing member (16) between surfaces of the lens tube and the camera housing; optionally wherein the sealing member (16) comprises: a first O-ring (42) compressed between the surface of the lens tube (24) and a lens tube ring (40); and a second O-ring (44) compressed between the surface of the camera housing (14) and the lens tube ring; wherein the first and second O-rings are separated by the lens tube ring and wherein the surface of the lens tube faces the surface of the camera housing.
  13. The method of claim 12, wherein the first bore (32) is deformed in the location force is applied by the threaded fastener (26).
  14. The method of claim 12 and further comprising engaging the threaded fastener (36) with a threaded insert (38) disposed in a second bore (34) of the camera housing, the second bore extending to the back side of the first bore, optionally wherein the threaded insert (26) is a thread locking insert, further optionally wherein the lens tube has a seating portion and a retention portion, the seating portion extending outward from and perpendicular to the lens tube to the retention portion, the retention portion extending parallel to the lens tube, and wherein the first and second O-rings are disposed between the retention portion and opposite sides of the seating portion.

Description

BACKGROUND The present disclosure relates generally to a camera for aircraft applications and more particularly to lens tube mounting. It is important to be able to focus a lens assembly via lens tube adjustment and positional locking during the manufacture of custom cameras for aircraft cabins or similar applications. The process of lens tube adjustment and locking can be time consuming and difficult. Rotating a threaded lens tube in a threaded bore of a camera housing can require repeated readjustment due to a clearance between threads. For example, a 5 degree over-rotation inward to focus may require a 10 degree outward rotation for correction because the clearance in the thread is biased to the opposite direction. The clearance in the thread is unavoidable even if tightly controlled and can result in the 5 degree shift in rotation without changing focus. A rotation dampener, such as O-ring, disposed around threads of the lens tube can aid in focusing, however, tactile feedback can vary depending on the direction of rotation as the rotation dampener is compressed and relaxed. It is additionally important to ensure that moisture is kept out of an image sensor area directly below the lens tube during operation. Sealing mechanisms are vital particularly for cameras that may be exposed to aerospace environmental requirements regarding moisture intrusion and susceptibility. New moisture resistant, camera lens tube interface designs that offer ease of focus adjustment and positional locking are needed. US 2020/0041874 A1 discloses an imaging device comprising a lens barrel contained within a housing with a waterproof seal. SUMMARY In one aspect of the invention, a positional lens locking assembly for focusing and maintaining focus of a camera lens assembly according to appended claim 1 is disclosed. In another aspect of the invention, a method of focusing and locking a lens tube of a camera assembly in position according to appended claim 11 is disclosed. The present summary is provided only by way of example, and not limitation. Other aspects of the present disclosure will be appreciated in view of the entirety of the present disclosure, including the entire text, claims and accompanying figures. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simplified cross-sectional view of a positional lens locking assembly.FIG. 2 is a flowchart of a method for focusing and locking a lens tube during manufacture of a camera assembly of FIG. 1. While the above-identified figure sets forth one embodiment of the present disclosure, other embodiments are also contemplated, as noted in the discussion. In all cases, this disclosure presents the invention by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art, which fall within the scope of the invention. The figure may not be drawn to scale, and applications and embodiments of the present invention may include features and components not specifically shown in the drawings. DETAILED DESCRIPTION FIG. 1 is a simplified cross-sectional view of positional lens locking assembly 10. Lens assembly 12, camera housing 14, sealing mechanism 16, positional locking mechanism 18, and camera assembly 20 are shown. Camera housing 14 contains camera assembly 20 and is configured to receive lens assembly 12. Camera assembly 20 includes image sensor 22. Lens assembly 12 includes lens tube 24. Lens tube 24 can include head 26 and barrel 28. Barrel 28 can include threaded portion 30. Camera housing 14 includes lens tube bore 32 and positional locking mechanism 18. Positional locking mechanism 18 can include locking bore 34, fastener 36, and threaded insert 38. Sealing mechanism 16 can include lens tube ring 40 and elastomeric members 42 and 44. Positional lens locking assembly 10 provides a relatively easy means for focusing and fixing lens assembly 12 while providing moisture intrusion resistance. Lens tube 24 is received in lens tube bore 32 of camera housing 14. Lens tube bore 32 can be threaded and configured to receive threaded portion 30 of lens tube 24. During a manufacturing process, lens assembly 12 is focused by rotating lens tube 24 clockwise and/or counterclockwise in lens tube bore 32 toward and/or away from image sensor 22 until an image appears in focus. Sealing mechanism 16 is compressed between surfaces of lens tube 24 and camera housing 14 and holds lens tube 24 in tension during rotation of lens tube 24. Sealing mechanism 16 allows the adjustment of focus inward and outward without hysteresis by maintaining lens tube 24 in tension. As lens tube 24 is rotated, sealing mechanism 16 can provide appropriate resistance to enable ease of minute adjustments with temporary anti-rotation hold once torquing force is removed. When a clear image is obtained, lens tube 24 is in a position of focus. Lens tube 24 can be locked in the position of focus with positional locking mechanism 18 as