Rotating contact assemblies for self-leveling camera heads
Camera heads and associated rotating contact assemblies are disclosed. In one embodiment a slip-ring assembly includes a rotating contact assembly including slip rings having a cylindrical ring assembly and a flexible or bendable brush assembly. Brush elements may flexed to remain in contact with corresponding ring assembly electrical contacts. Bush contacts may be coated or have attached contact assemblies to increase hardness and oxide resistance with materials such as palladium nickel, rhodium, or hard gold, though a variety of other materials may be used as a suitable coating.
1. A camera head, comprising:
a cylindrical housing;
an imager disposed within the housing on a first element movable relative to the housing;
a second element rotationally movable relative to the first element, the second element including an electrical output connection; and
a slip ring coupled between the first element and the second element to provide an electrical connection between an output of the imager and the electrical output connection, wherein the slip ring comprises:
a cylindrical rotor assembly including a plurality of electrical contacts disposed circumferentially thereon; and
a stator assembly disposed in flexion around the cylindrical rotor assembly, the stator assembly including one or more printed circuit board brush elements having electrical contacts thereon, where the electrical contacts are electrical circuit traces on the one or more printed circuit board brush elements for providing electrical coupling to corresponding rotor assembly electrical contacts and where the brush element electrical contacts are held in contact with corresponding ones of the one or more ring electrical contacts through the flexion of the stator assembly.
2. The camera head of claim 1 , further including a counterweight to self-level the imager via gravity.
3. The camera head of claim 1 , wherein the stator assembly comprises two printed circuit board brush elements having contacts thereon.
4. The camera head of claim 3 , wherein the two printed circuit brush elements have finger with the electrical contacts thereon and the printed circuit brush elements and corresponding electrical contacts are interleaved.
5. The camera head of claim 1 , wherein the printed circuit board brush element electrical contacts are coated with one or more of palladium, nickel, rhodium, and hard gold to decrease frictional contact erosion and/or corrosion.
6. The camera head of claim 1 , wherein the cylindrical rotor assembly includes three or more contact rings and one or more dielectric separate rings.
7. The camera head of claim 6 , further including a contact guide cap.
8. The camera head of claim 1 , further comprising a lubricant disposed on a slip contact surface of the cylindrical rotor assembly.
9. The camera head of claim 1 , further comprising a grease or flypaper placed inside the housing to scavenge dirt and debris.
10. The camera head of claim 9 , wherein the grease or flypaper is disposed on one or more contact surfaces of the slip ring.
11. The camera head of claim 1 , wherein at least one of the electrical connections is soldered with a low temperature, compliant solder.
12. The camera head of claim 11 , wherein the low temperate, compliant solder comprises one or more of Alpha WS-852, Indium Corp. alloys 281, and Indium Corp. alloys 282.
13. The camera head of claim 1 , further comprising a desiccant material disposed in the housing to remove moisture.
14. The camera head of claim 1 , wherein the position of the slip rings and brushes are interchanged between the first element and the second element.
15. The camera head of claim 1 , wherein the camera head includes one or more bearings.
16. The camera head of claim 15 , wherein the bearing are ball bearings including ceramic balls.
17. The camera head of claim 1 , wherein the rings are fabricated using an oven reflow soldering process.
18. A camera head, comprising:
a housing;
an imager disposed within the housing on a first element movable relative to the housing;
a second element rotationally movable relative to the first element, the second element including an electrical output connection; and
a slip ring coupled between the first element and the second element to provide an electrical connection between an output of the imager and the electrical output connection, wherein the slip ring comprises:
a cylindrical ring assembly including one or more ring electrical contacts; and
a brush assembly disposed around the cylindrical ring assembly, the brush assembly comprising one or more printed circuit brush elements each including one or more elongate cantilevers arranged in a spaced apart relationship thereto and each elongate cantilever having one or more brush electrical contacts disposed thereon as printed circuit board electrical traces, wherein the elongate cantilevers are flexed to conform to shape of the cylindrical ring assembly at a contact surface area to position the brush electrical contacts in a substantially flat and continuous contact arrangement with corresponding one or more ring electrical contacts.