Rotary knob mechanical encoder
A rotary knob for operating an electronically actuable deadbolt is described herein. According to some embodiments, the rotary knob includes a chassis, an outer wall rotatably coupled to the chassis about a central axis of the knob, a cantilevered beam attached to an inner surface of the outer wall and extending towards the central axis of the knob such that the beam is configured to rotate with the outer wall about the central axis, a circuit board coupled to the chassis, the circuit board including signal traces, and an electrical contact extending from the cantilevered beam in a direction toward the signal traces and electrically connectable with the signal traces. A controller of the rotary knob is configured to determine a position of the deadbolt based on at least the state of the electrical connection between the electrical contact and the signal traces.
1. A rotary knob for operating an electronically actuatable deadbolt, the rotary knob comprising:
a chassis;
an outer wall rotatably coupled to the chassis about a central axis of the rotary knob;
a cantilevered beam attached to an inner surface of the outer wall and extending towards the central axis of the rotary knob such that the cantilevered beam is configured to rotate with the outer wall about the central axis;
a circuit board coupled to the chassis, the circuit board including a first signal trace, and
an electrical contact extending from the cantilevered beam in a direction toward the first signal trace and electrically connectable with the first signal trace.
2. The rotary knob of claim 1 , further comprising a controller configured to determine a position of the deadbolt based on at least a state of electrical connection between the electrical contact and at least the first signal trace.
3. The rotary knob of claim 1 , wherein the cantilevered beam includes a free-end adjacent the central axis, the free-end of the cantilevered beam being operatively coupled to a removable adaptor configured to receive a cam shaft that actuates the deadbolt, and wherein rotation of the outer wall and the cantilevered beam rotates the adaptor about the central axis which rotates the cam shaft and actuates the deadbolt.
4. The rotary knob of claim 1 , wherein the cantilevered beam includes a fixed end coupled to the inner surface of the outer wall, and wherein the fixed end of the cantilevered beam flares laterally.
5. The rotary knob of claim 4 , further comprising a first stopper, wherein the fixed end of the cantilevered beam is configured to engage the first stopper to limit rotation of the outer wall.
6. The rotary knob of claim 5 , further comprising a second stopper, wherein the fixed end of the cantilevered beam is configured to engage the second stopper to limit rotation of the outer wall.
7. The rotary knob of claim 6 , wherein the first and second stoppers limit rotation of the outer wall such that the electrical contact is always in contact with at least one of the plurality of signal traces.
8. The rotary knob of claim 7 , wherein the first and second stoppers are positioned at opposing diametric ends of the chassis.
9. The rotary knob of claim 7 , wherein the first and second stoppers limit rotation of the outer wall over a rotation range of 170 degrees.
10. The rotary knob of claim 5 , wherein the fixed end of the cantilevered beam at least partially wraps around the first stopper when engaging the first stopper.
11. The rotary knob of claim 4 , wherein the first signal trace is one of a plurality of signal traces.
12. The rotary knob of claim 11 , wherein the electrical contact comprises one or more leaf springs each configured to elastically deform when in contact with a respective one of the plurality of signal traces.
13. The rotary knob of claim 12 , wherein at least one of the one or more leaf springs comprises a multi-pronged contact end.
14. The rotary knob of claim 11 , wherein the plurality of signal traces are arranged along a plurality of continuous arcs on the circuit board.
15. The rotary knob of claim 14 , wherein the signal traces are arranged along a plurality of arcs, wherein the arcs are concentric about the central axis.
16. The rotary knob of claim 15 , wherein the circuit board is divided into a plurality of sectors, the signal traces are arranged such that the electrical contact is electrically connected with a unique combination of the plurality of signal traces while in each of the plurality of sectors, and a controller is configured to determine a position of the deadbolt based on at least the combination of the plurality of signal traces electrically connected to the electrical contact.
17. The rotary knob of claim 16 , wherein the combination of the plurality of signal traces electrically connected to the electrical contact differs by one signal trace between adjacent sectors of the plurality of sectors.
18. The rotary knob of claim 16 , wherein the electrical contact comprises one or more leaf springs configured to elastically deform when in contact with one or more of the plurality of signal traces.
19. The rotary knob of claim 11 , wherein the plurality of signal traces is arranged along a plurality of discontinuous arcs on the circuit board.
20. The rotary knob of claim 1 , wherein:
the first signal trace is one of a plurality of signal traces, the plurality of signal traces further comprising a second signal trace and a third signal trace;
the plurality of signal traces are arranged along a plurality of lines on the circuit board, the plurality of lines comprising a first line and a second line;
the first signal trace and the second signal trace are arranged in the first line; and
the third signal trace is arranged in the second line.
21. The rotary knob of claim 20 , wherein a non-conductive area is further arranged on the circuit board in the first line separating the first signal trace and the second signal trace.