Back to results
US 10,094,450 B2Granted
Rotational tensioner with stored energy and damping feature
AssigneeBorgWarner Inc.
InventorsSean R. Simmons, Simon Barrette
Life of this patent
Estimating the term…
Abstract
A tensioner uses a low rate torsion spring in a first stage and a high rate torsion spring in a second stage to maintain tension in a chain or belt. The first stage is connected to the second stage by a torque coupling. The high rate torsion spring is maintained in an energized state between a ground and a dead stop to store energy and to provide tension under high loads. In some embodiments, the torque coupling is a damper. In other embodiments, the torque coupling is a clutch. A method stores energy in a high rate torsion spring of a tensioner.
Claims14
A tensioner comprising:
- a first stage (20, 60, 120) comprising:
- an arm (23, 63, 123) comprising a body having a first end extending outwardly from a second end pivotable around a pivot axis, the body receiving torque applied by a load from a chain or belt, and a first ground (24, 64, 124) extending from the body parallel to the pivot axis;
- and
- a low rate torsion spring (25, 125) mounted around the pivot axis and having a first end contacting the first ground (24, 64, 124) to resist rotation of the arm in a first direction around the pivot axis;
- a torque coupling (40, 80, 140) mounted around the pivot axis and receiving torque from the first stage (20, 60, 120);
- and
- a second stage (30, 70, 130) receiving torque transmitted by the torque coupling (40, 80, 140), the second stage comprising:
- a second stage housing (31, 71, 131) rotatable about the pivot axis, the second stage housing having a spring trap (34, 74, 134);
- a high rate torsion spring (33, 133) rotatable with the second stage housing (31, 71, 131), the high rate torsion spring having a first end (151) extending through the spring trap (34, 74, 134) of the second stage housing (31, 71, 131) and a second end (150) opposite the first end (151);
- a dead stop (78, 138), non-rotatable with respect to the pivot axis, extending parallel to the pivot axis, and contacting the first end (151) of the high rate torsion spring (33, 133), when no load is being applied to the arm (23, 63, 123) by the chain or belt;
- and
- a second ground (77, 137), non-rotatable with respect to the pivot axis, extending parallel to the pivot axis, and contacting the second end (150) of the high rate torsion spring (33, 133), when no load is being applied to the arm by the chain or belt;
- wherein the high rate torsion spring (33, 133) is held in an energized state by the dead stop (78, 138) and the second ground (77, 137) when no load is being applied to the arm (23, 63, 123) by the chain or belt.
10 more elements
A method of storing energy in a high rate torsion spring (33, 133) of a tensioner, the method comprising the steps of:
- a) mounting the high rate torsion spring (33, 133) on a second stage housing (31, 71, 131) of the tensioner such that a first end of the high rate torsion spring extends through a spring trap (34, 74, 134) in the second stage housing (31, 71, 131), the tensioner comprising:
- a first stage (20, 60, 120) comprising:
- an arm (23, 63, 123) comprising a body having a first end extending outwardly from a second end pivotable around a pivot axis, the body receiving torque applied by a load from a chain or belt, and a first ground (24, 64, 124) extending from the body parallel to the pivot axis;
- and
- a low rate torsion spring (25,125) mounted around the pivot axis and having a first end located to the first ground (24, 64, 124) to resist rotation of the arm in a first direction around the pivot axis;
- a torque coupling (40, 80, 140) mounted around the pivot axis and receiving torque from the first stage (20, 60, 120);
- and
- a second stage (30, 70, 130) receiving torque transmitted by the torque coupling (40, 80, 140), the second stage comprising:
- the second stage housing (31, 71, 131) rotatable about the pivot axis;
- and
- the high rate torsion spring (33, 133) having the first end (151) extending through the spring trap (34, 74, 134) of the second stage housing (31, 71, 131) and a second end (150) opposite the first end (151);
- b) energizing the high rate torsion spring (33, 133) and pinning the first end (151) of the high rate torsion spring (33, 133) in contact with a dead stop (78, 138), non-rotatable with respect to the pivot axis and extending parallel to the pivot axis, and the second end (150) of the high rate torsion spring (33, 133) in contact with a second ground (77,137), non-rotatable with respect to the pivot axis and extending parallel to the pivot axis, such that the high rate torsion spring (33, 133) is held in an energized state by the dead stop (78, 138) and the second ground (77, 137) when no load is being applied to the arm (23, 63,123) by the chain or belt.
9 more elements
Dependencies are inferred from the claim text.