Auto-centre barrel cam for small optical systems
An auto-center barrel cam for small optical systems including an outer barrel having a first channel extending longitudinally where the first channel is tapered from an inner surface to an outer surface of the outer barrel at a first angle and an inner barrel within the outer barrel. The inner barrel including a second channel extending longitudinally along the inner barrel where the second channel is tapered from an inner surface to an outer surface of the inner barrel at a second angle. A cam follower includes a flexure part having a first section with a first surface and a second section with a second surface. A spring section pulls the first section and the second section toward each other. The flexure part is arranged to maintain the cam follower within a center of the first and second channels as the inner barrel moves in relation to the outer barrel.
1. An auto-center barrel cam comprising:
an outer barrel including a first channel extending longitudinally along the outer barrel, the first channel being tapered on both a first side and second side from an inner surface to an outer surface of the outer barrel outwardly at a first angle;
an inner barrel within the outer barrel, the inner barrel having an outer surface adjacent to the inner surface of the outer barrel, the inner barrel including a second channel extending longitudinally along the inner barrel, the second channel being tapered on both a first side and a second side from an outer surface to an inner surface of the inner barrel inwardly at a second angle; and
a cam follower including:
a flexure part having a first section with a first surface, a second section with a second surface, a spring section between the first section and the second section configured to pull the first section and the second section toward each other, the first section being tapered at a third angle opposite the first angle to maintain the first surface in contact with a surface along the first tapered channel of the outer barrel and the second section being tapered at a fourth angle opposite the second angle to maintain the second surface in contact with a surface along the second tapered channel of the inner barrel; and
wherein, the flexure part is arranged to maintain the cam follower within a center of the first and second channels as the inner barrel moves in relation to the outer barrel.
2. The cam of claim 1 , wherein the first section and the second section form an hour-glass like shape.
3. The cam of claim 1 , wherein the flexure part is mounted on the cam follower.
4. The cam of claim 1 , wherein, the cam follower includes a connector arranged to connect the cam follower to a cam follower base.
5. The cam of claim 4 , wherein the connector includes a screw part arranged to threadable engage with the cam follower base.
6. The cam of claim 1 comprising a through hole extending from the first section to the second section.
7. The cam of claim 1 , wherein the first channel extends longitudinally along the outer barrel in at least one of a wrapped and non-linear path.
8. The cam of claim 7 , wherein the second channel extends longitudinally along the inner barrel in a linear path.
9. The cam of claim 1 , wherein the first angle and second angle is between 30 degrees and 90 degrees extending from the inner surface to an outer surface of the inner barrel and the outer barrel respectively.
10. The cam of claim 1 , wherein the spring section includes a helical spring.
11. An optical scope for a firearm comprising:
an optical assembly arranged to image a target; and
an auto-center barrel cam including:
an outer barrel including a first channel extending longitudinally along the outer barrel, the first channel being tapered on both a first side and second side from an inner surface to an outer surface of the outer barrel outwardly at a first angle;
an inner barrel within the outer barrel, the inner barrel having an outer surface adjacent to the inner surface of the outer barrel, the inner barrel including a second channel extending longitudinally along the inner barrel, the second channel being tapered on both a first side and a second side from an outer surface to an inner surface of the inner barrel inwardly at a second angle; and
a cam follower including:
a flexure part having a first section with a first surface, a second section with a second surface, a spring section between the first section and the second section configured to pull the first section and the second section toward each other, the first section being tapered at a third angle opposite the first angle to maintain the first surface in contact with a surface along the first tapered channel of the outer barrel and the second section being tapered at a fourth angle opposite the second angle to maintain the second surface in contact with a surface along the second tapered channel of the inner barrel; and
wherein, the flexure part is arranged to maintain the cam follower within a center of the first and second channels as the inner barrel moves in relation to the outer barrel.
12. The cam of claim 11 , wherein the first section and the second section form an hour-glass like shape.
13. The cam of claim 11 , wherein the flexure part is mounted on the cam follower.
14. The cam of claim 11 , wherein, the cam follower includes a connector arranged to connect the cam follower to a cam follower base.
15. The cam of claim 14 , wherein the connector includes a screw part arranged to threadable engage with the cam follower base.
16. The cam of claim 11 comprising a through hole extending from the first section to the second section.
17. The cam of claim 11 , wherein the first channel extends longitudinally along the outer barrel in at least one of a wrapped and non-linear path.
18. The cam of claim 17 , wherein the second channel extends longitudinally along the inner barrel in a linear path.
19. The cam of claim 11 , wherein the first angle and second angel is between 30 degrees and 90 degrees extending from the inner surface of the outer barrel.
20. A method for manufacturing an auto-center barrel cam comprising:
providing an outer barrel including a first channel extending longitudinally along the outer barrel, the first channel being tapered on both a first side and second side from an inner surface to an outer surface of the outer barrel outwardly at a first angle;
providing an inner barrel within the outer barrel, the inner barrel having an outer surface adjacent to the inner surface of the outer barrel, the inner barrel including a second channel extending longitudinally along the inner barrel, the second channel being tapered on both a first side and a second side from an outer surface to an inner surface of the inner barrel inwardly at a second angle; and
connecting the outer barrel to the inner barrel via a cam follower, the cam follower including:
a flexure part having a first section with a first surface, a second section with a second surface, a spring section between the first section and the second section configured to pull the first section and the second section toward each other, the first section being tapered at a third angle opposite the first angle to maintain the first surface in contact with a surface along the first tapered channel of the outer barrel and the second section being tapered at a fourth angle opposite the second angle to maintain the second surface in contact with a surface along the second tapered channel of the inner barrel; and
wherein, the flexure part is arranged to maintain the cam follower within a center of the first and second channels as the inner barrel moves in relation to the outer barrel.