Torque-limiting nut
A torque-limiting nut is provided. The torque-limiting nut has a washer, a threaded component, and a tool interface. The threaded component has a plurality of detents and the tool interface has a corresponding plurality of recesses and a spring groove. A plurality of engagement members are sized and shaped to fit within the plurality of detents and recesses. An elastic member in the spring grooves provides a compressive force to seat the pins in the corresponding detents to frictionally couple the threaded component and tool interface. When a torque required to rotate the tool interface exceeds a predetermined value, the pin moves against the spring and unseats from the detent such that the tool interface rotates without rotating the threaded component.
1 . A torque-limiting nut comprising,
a threaded component, the threaded component comprising:
a main body extending axially from a first end to a second end with an outer surface and having an internally threaded through channel,
a flanged portion having a radially extending first side, a radially extending second side opposite the radially extending first side, and an axially extending side surface to connect the radially extending first side and radially extending the second side wherein the flanged portion extends in a radially outward direction from the main body at a first end, and
at least one detent on at least one of the radially extending first side or the radially extending second side of the flanged portion;
a tool interface having at least one flat surface configured to engage a tool and an internal channel sized to receive the main body, the tool interface comprising at least one recess corresponding to the at least one detent;
at least one engagement member for each of the at least one detent wherein the at least one engagement member is configured to reside, in part, in the at least one detent and, in part, in the at least one recess; and
at least one elastic member that provides a force on the at least one engagement member to seat the at least one engagement member in the at least one detent.
2 . The torque-limiting nut of claim 1 wherein the at least one detent is a plurality of detents, the at least one recess is a plurality of recesses, and the at least one engagement member is a plurality of engagement members.
3 . The torque-limiting nut of claim 1 wherein the second side of the flanged portion is a tool interface side and the at least one detent resides in the tool interface side of the flange portion.
4 . The torque-limiting nut of claim 1 wherein the main body has an axially extending outer surface and the at least one detent resides in the axially extending outer surface.
5 . The torque-limiting nut of claim 3 wherein the at least one recess extends axially in the tool interface.
6 . The torque-limiting nut of claim 5 wherein the elastic member extends axially in the at least one recess to seat the at least one engagement member into the at least one detent in the flanged portion.
7 . The torque-limiting nut of claim 6 wherein the at least one recess is a through recess terminating with a retainer.
8 . The torque-limiting nut of claim 5 wherein the at least one recess is open to the internal channel.
9 . The torque-limiting nut of claim 1 wherein the elastic member is a spring.
10 . A torque-limiting nut configured to engage a spindle comprising,
a threaded component and a washer coupled to the threaded component by a first retaining device configured to retain the washer to the threaded component, the threaded component comprising:
a main body extending axially from a first end to a second end with an outer surface and having an internally threaded through channel,
a flanged portion extending in a radially outward direction from the main body at a first end, and
a plurality of detents;
the washer comprising:
an anti-rotation device;
a tool interface having an internal channel sized to receive the main body, the tool interface comprising a plurality of recesses;
a plurality of engagement members engaged with the plurality of detents and plurality of recesses such that the plurality of detents remain in the detent to allow rotation when a force required to rotate the tool interface is below a torque limit and the plurality of engagement members move out of the plurality of detents when the force required to rotate the tool interface exceeds the torque limit.
11 . The torque-limiting nut configured to engage the spindle of claim 10 wherein the plurality of engagement members comprises a plurality of pins and at least one spring.
12 . The torque-limiting nut configured to engage the spindle of claim 10 wherein the plurality of engagement members comprise a plurality of balls and a plurality of springs.
13 . The torque-limiting nut configured to engage the spindle of claim 10 wherein the anti-rotation device is a tang.
14 . The torque-limiting nut configured to engage the spindle of claim 10 wherein the anti-rotation device is a flat.
15 . The toque-limiting nut configure to engage the spindle of claim 10 comprising a second retaining device configured to retain the tool interface and the threaded component.
16 . The torque-limiting nut configured to engage the spindle of claim 10 wherein the first retention device comprises a first groove on the threaded component, a second groove on the washer aligned with the first groove, and a retention ring residing in both the first and second groove.