Resettable mechanical disconnect
A resettable mechanical disconnect comprises: first and second shafts having coupling features to engage each other such that first and second shafts rotate together around first axis; axial surface of ramp increasing in height around outer surface of second shaft around first axis; pawl and spring to rotate toward radial surface of ramp of second shaft; movable pin to retain pawl in place away from ramp when extended; control mechanism to retract movable pin; when control mechanism causes movable pin to retract, spring causes pawl to rotate about second axis to contact radial surface of ramp; pawl applies pressure against ramp as it rotates and pressure of pawl against increase in height of axial surface of ramp causes second shaft to move away from first shaft axially along first axis such that coupling features shafts disengage to cause first shaft and second shaft to no longer rotate together.
1 . A resettable mechanical disconnect, comprising:
a first shaft portion positioned about a first axis and having first coupling features positioned at a first end of the first shaft portion; and
a second shaft portion positioned about the first axis and adjacent to the first shaft portion, the second shaft portion having:
second coupling features positioned at a second end of the second shaft portion and configured to engage with the first coupling features of the first shaft portion to cause the first shaft portion and the second shaft portion to rotate together radially about the first axis; and
a ramp section positioned around an outer surface of the second shaft portion, an axial surface of the ramp section increasing in height, substantially parallel to the first axis, around the outer surface of the second shaft portion about the first axis;
a controllable spring loaded rotatable pawl apparatus having:
a pawl configured to rotate about a second axis toward a radial surface of the ramp section of the second shaft portion;
a spring configured to cause the pawl to rotate about the second axis toward the radial surface of the ramp section of the second shaft portion;
a movable pin configured to retain the pawl in place away from the ramp section when extended; and
a control mechanism configured to retract the movable pin based on an electrical control signal;
when the control mechanism causes the movable pin to retract, the spring causes the pawl to rotate about the second axis to come into contact with the radial surface of the ramp section of the second shaft portion; and
as the pawl applies pressure against the ramp section of the second shaft portion as the ramp section of the second shaft portion rotates about the first axis, the pressure of the pawl against an increase in the height, substantially parallel to the first axis, of the axial surface of the ramp section of the second shaft portion about the first axis causes the second shaft portion to move away from the first shaft portion axially along the first axis such that the second coupling features of the second shaft portion disengage from the first coupling features of the first shaft portion to cause the first shaft portion and the second shaft portion to no longer rotate together, thereby mechanically disconnecting the second shaft portion from the first shaft portion.
2 . The resettable mechanical disconnect of claim 1 , further comprising:
wherein the pawl is configured to be rotated about the second axis and back into a position where a portion of the pawl is past the movable pin; and
wherein the movable pin is configured to extend so that the movable pin holds the pawl from rotating about the second axis and prevents the pawl from coming into contact with the ramp section of the second shaft portion of the resettable mechanical disconnect.
3 . The resettable mechanical disconnect of claim 1 , further comprising:
wherein the height, substantially parallel to the first axis, of the axial surface of the ramp section increases around the outer surface of the second shaft portion as a first width, substantially parallel to the first axis, of the radial surface of the ramp section of the outer surface of the second shaft portion decreases around the second shaft portion.
4 . The resettable mechanical disconnect of claim 3 , further comprising:
wherein the first width, substantially parallel to the first axis, of the radial surface of the ramp section of the outer surface of the second shaft portion is wider than a second width, substantially parallel to the second axis, of the pawl in a first section of the ramp section.
5 . The resettable mechanical disconnect of claim 1 , further comprising:
when the control mechanism causes the movable pin to retract, the spring causes the pawl to rotate about the second axis to initially come into radial contact with the radial surface of the ramp section of the outer surface of the second shaft portion.
6 . The resettable mechanical disconnect of claim 1 , further comprising:
wherein the height, substantially parallel to the first axis, of the axial surface of the ramp section increases around the outer surface of the second shaft portion as a first width, substantially parallel to the first axis, of the radial surface of the ramp section of the outer surface of the second shaft portion decreases around the second shaft portion;
wherein the first width, substantially parallel to the first axis, of the radial surface of the ramp section of the outer surface of the second shaft portion is wider than a second width, substantially parallel to the second axis, of the pawl in a first section of the outer surface; and
when the control mechanism causes the movable pin to retract, the spring causes the pawl to rotate about the second axis to initially come into radial contact with the radial surface of the ramp section of the outer surface of the second shaft portion in the first section of the ramp section of the outer surface without being in axial contact with the axial surface of the ramp section.
7 . The resettable mechanical disconnect of claim 6 , further comprising:
wherein the pawl comes into the axial contact with the axial surface of the ramp section as the second shaft portion rotates causing the pawl to apply the pressure against the axial surface of the ramp section of the second shaft portion.
8 . The resettable mechanical disconnect of claim 1 , further comprising:
wherein the second shaft portion moves into a cavity of a third shaft portion as the second shaft portion moves away from the first shaft portion axially along the first axis.
9 . The resettable mechanical disconnect of claim 8 , further comprising:
wherein the second shaft portion comprises guiding surfaces that are smaller in outer diameter than corresponding guiding surfaces on an inner diameter of the cavity of the third shaft portion, wherein the guiding surfaces of the second shaft portion and the corresponding guiding surfaces of the third shaft portion guide the second shaft portion inside the cavity of the third shaft portion as the second shaft portion moves away from the first shaft portion axially along the first axis.
10 . A method of operating a resettable mechanical disconnect, comprising:
receiving an electrical control signal at a control mechanism;
causing, based on the electrical control signal received at the control mechanism, a movable pin to retract, allowing a spring to cause a pawl to rotate about a first axis to come into contact with a radial surface of a ramp section of a first shaft portion of a resettable mechanical disconnect; and
allowing the spring to cause the pawl to apply pressure against an axial surface of the ramp section of the first shaft portion as the ramp section of the first shaft portion rotates about a second axis, the pressure of the pawl against an increase in height, substantially parallel to the first axis, of the axial surface of the ramp section of the first shaft portion about the second axis cause the first shaft portion to move away from a second shaft portion axially along the second axis such that first coupling features of the first shaft portion disengage from second coupling features of the second shaft portion to cause the first shaft portion and the second shaft portion to no longer rotate together, thereby mechanically disconnecting the first shaft portion from the second shaft portion.
11 . The method of claim 10 , further comprising resetting the resettable mechanical disconnect by:
rotating the pawl about the second axis and back into a position where a portion of the pawl is past the movable pin; and
extending the movable pin so that the movable pin holds the pawl from rotating about the second axis and prevents the pawl from coming into contact with the ramp section of the first shaft portion of the resettable mechanical disconnect.
12 . The method of claim 10 , further comprising:
wherein the height, substantially parallel to the first axis, of the axial surface of the ramp section increases around an outer surface of the second shaft portion as a first width, substantially parallel to the first axis, of the outer surface of the radial surface of the ramp section of the second shaft portion decreases around the second shaft portion.
13 . The method of claim 12 , further comprising:
wherein the first width, substantially parallel to the first axis, of the radial surface of the ramp section of the outer surface of the second shaft portion is wider than a second width, substantially parallel to the second axis, of the pawl in a first section of the ramp section.
14 . The method of claim 10 , further comprising:
when the control mechanism causes the movable pin to retract, the spring causes the pawl to rotate about the second axis to initially come into radial contact with the radial surface of the ramp section of an outer surface of the second shaft portion.
15 . The method of claim 10 , further comprising:
wherein the height, substantially parallel to the first axis, of the axial surface of the ramp section increases around an outer surface of the second shaft portion as a first width, substantially parallel to the first axis, of the radial surface of the ramp section of the outer surface of the second shaft portion decreases around the second shaft portion;
wherein the first width, substantially parallel to the first axis, of the outer surface of the ramp section of the outer surface of the second shaft portion is wider than a second width, substantially parallel to the second axis, of the pawl in a first section of the outer surface; and
allowing the spring to cause the pawl to initially come into radial contact with the radial surface of the ramp section of the outer surface of the second shaft portion in the first section of the ramp section of the outer surface without being in axial contact with the axial surface of the ramp section.
16 . The method of claim 15 , further comprising:
allowing the spring to cause the pawl to come into the axial contact with the axial surface of the ramp section as the second shaft portion rotates causing the pawl to apply the pressure against the axial surface of the ramp section of the second shaft portion.
17 . The method of claim 10 , further comprising:
wherein the second shaft portion moves into a cavity of a third shaft portion as the second shaft portion moves away from the first shaft portion axially along the first axis.
18 . The method of claim 17 , further comprising:
using guiding surfaces of the second shaft portion that are smaller in outer diameter than corresponding guiding surfaces on an inner diameter of the cavity of the third shaft portion to guide the second shaft portion inside the cavity of the third shaft portion as the second shaft portion moves away from the first shaft portion axially along the first axis.
19 . A resettable mechanical disconnect, comprising:
a first shaft portion positioned about a first axis and having first coupling features positioned at a first end of the first shaft portion;
a second shaft portion positioned about the first axis and adjacent to the first shaft portion, the second shaft portion having:
second coupling features positioned at a second end of the second shaft portion and configured to engage with the first coupling features of the first shaft portion to cause the first shaft portion and the second shaft portion to rotate together radially about the first axis; and
a ramp section positioned around an outer surface of the second shaft portion, an axial surface of the ramp section increasing in height, substantially parallel to the first axis, around the outer surface of the second shaft portion about the first axis, wherein the height, substantially parallel to the first axis, of the axial surface of the ramp section increases around the outer surface of the second shaft portion as a first width, substantially parallel to the first axis, of a radial surface of the ramp section of the outer surface of the second shaft portion decreases around the second shaft portion;
a controllable spring loaded rotatable pawl apparatus having:
a pawl configured to rotate about a second axis toward the radial surface of the ramp section of the second shaft portion;
a spring configured to cause the pawl to rotate about the second axis toward the radial surface of the ramp section of the second shaft portion;
a movable pin configured to retain the pawl in place away from the ramp section when extended; and
a control mechanism configured to retract the movable pin based on an electrical control signal;
when the control mechanism causes the movable pin to retract, the spring causes the pawl to rotate about the second axis to initially come into radial contact with the radial surface of the ramp section of the outer surface of the second shaft portion in a first section of the ramp section of the outer surface without being in axial contact with the axial surface of the ramp section, wherein the first width, substantially parallel to the first axis, of the radial surface of the ramp section of the outer surface of the second shaft portion is wider than a second width, substantially parallel to the second axis, of the pawl in the first section of the outer surface, wherein the pawl subsequently comes into the axial contact with the ramp section as the second shaft portion rotates causing the pawl to apply pressure against the ramp section of the second shaft portion; and
as the pawl applies the pressure against the ramp section of the second shaft portion as the ramp section of the second shaft portion rotates about the first axis, the pressure of the pawl against an increase in the height, substantially parallel to the first axis, of the ramp section of the second shaft portion about the first axis causes the second shaft portion to move away from the first shaft portion axially along the first axis such that the second coupling features of the second shaft portion disengage from the first coupling features of the first shaft portion to cause the first shaft portion and the second shaft portion to no longer rotate together, thereby mechanically disconnecting the second shaft portion from the first shaft portion.
20 . The resettable mechanical disconnect of claim 19 , further comprising:
wherein the second shaft portion moves into a cavity of a third shaft portion as the second shaft portion moves away from the first shaft portion axially along the first axis; and
wherein the second shaft portion comprises guiding surfaces that are smaller in outer diameter than corresponding guiding surfaces on an inner diameter of the cavity of the third shaft portion, wherein the guiding surfaces of the second shaft portion and the corresponding guiding surfaces of the third shaft portion guide the second shaft portion inside the cavity of the third shaft portion as the second shaft portion moves away from the first shaft portion axially along the first axis.