Damping mechanism
View Patent ↗An asymmetric damping mechanism for use in a belt tensioner. The damping mechanism comprises two parts having substantially similar arcuate shapes for engaging a tensioner. The first part is in contact with the second part at a pivotable point of contact. The point of contact position is determined according to the desired asymmetric damping factor. The first part is also in contact with a spring. The second part is in contact with a tensioner arm. The damping mechanism also comprises two damping shoes, each having a damping band. The damping band is joined to the damping shoe by a plurality of vertical grooves on the damping shoe cooperating with a plurality of grooves on the damping band. The damping mechanism has an asymmetric damping factor in the range of approximately 1.5 to 5.
1. A damping mechanism comprising:
a damping shoe having an arcuate form;
a damping band engaged with the damping shoe by a locking mechanism comprising a groove and cooperating rib, the locking mechanism opposing a frictional force imparted to the damping band during operation;
a protrusion extending from the damping band for engaging a cooperating recess in the damping shoe;
a lip in the damping band for engaging the damping shoe;
the damping shoe comprising a surface for supporting a spring coil; and
the damping shoe comprising a spring receiving portion having two spring contact points for contacting a spring.
2. The damping mechanism as in claim 1 further comprising:
a second damping shoe having an arcuate form;
a second damping band engaged with the second damping shoe by a second locking mechanism, the second locking mechanism disposed to opposed a frictional force imparted to the second damping band during operation.
3. The damping mechanism as in claim 2 further comprising:
a protrusion extending from the second damping band for engaging a cooperating recess in the second damping shoe.
4. The damping mechanism as in claim 2 further comprising:
a lip in the second damping band for engaging the second damping shoe.
5. The damping mechanism as in claim 2 further comprising:
the damping shoe engaged with the second damping shoe at a point of contact;
the point of contact disposed a radial distance from a lever arm axis of rotation whereby an asymmetric damping factor is achieved.
6. The damping mechanism as in claim 5 , wherein the asymmetric damping factor is in the range of approximately 1.5 to 5.
7. The damping mechanism as in claim 2 , wherein the locking mechanism comprises a groove and cooperating rib.
8. A tensioner comprising;
a base;
a lever arm pivotally engaged to the base;
a pulley journalled to the lever arm;
a damping mechanism engaged with the lever arm and frictionally engaged with the base;
the damping mechanism comprises a damping shoe engaged with damping band by a groove on an engagement surface, the groove oriented to opposed a frictional force imparted to the damping band during operation;
a spring engaged with the damping shoe and the base;
the damping shoe comprising a spring receiving portion having two spring contact points for contacting a spring end whereby a pair of reaction forces are created;
a protrusion extending from the damping band for engaging a cooperating recess in the damping shoe; and
the damping mechanism having an asymmetric damping factor.
9. The tensioner as in claim 8 , wherein the damping mechanism further comprises:
a lip in the damping band for engaging the damping shoe.