Driven pulley for a continuously variable transmission
A driven pulley for a continuously variable transmission has a fixed sheave; a movable sheave; a spring biasing the movable sheave axially toward the fixed sheave; and at least one roller assembly connected to one of the sheaves. Another one of the sheaves has at least one ramp configured for abutting the at least one roller assembly. Each roller assembly has: a pin and a roller. The pin has: a first pin portion received in an aperture defined in the one of the sheaves; a second pin portion extending radially from the one of the sheaves; and an annular flange disposed radially between the first and second pin portions. The flange abuts a surface of the one of the sheaves surrounding the aperture. The roller is disposed on the second pin portion. The annular width of the flange is at least half of the annular width of the roller.
1 . A driven pulley for a continuously variable transmission comprising:
a fixed sheave;
a movable sheave operatively connected to the fixed sheave, the movable sheave being movable axially relative to the fixed sheave;
a spring biasing the movable sheave axially toward the fixed sheave; and
at least one roller assembly connected to one of the fixed sheave and the movable sheave,
another one of the fixed sheave and the movable sheave having at least one ramp configured for abutting the at least one roller assembly;
each roller assembly of the at least one roller assembly having:
a pin defining a radially extending pin axis, the pin having:
a first pin portion received in an aperture defined in the one of the fixed sheave and the movable sheave;
a second pin portion extending radially from the one of the fixed sheave and the movable sheave; and
an annular flange extending from and disposed radially between the first pin portion and the second pin portion, the flange having a first annular width, the flange abutting a surface of the one of the fixed sheave and the movable sheave surrounding the aperture; and
a roller disposed on the second pin portion, the roller being rotatable about the pin axis, the roller being axially and radially between the fixed sheave and the movable sheave, the roller having at least one annular portion, the at least one annular portion of the roller having a second annular width,
the first annular width being at least half of the second annular width.
2 . The driven pulley of claim 1 , wherein the movable sheave is rotatable relative to the fixed sheave.
3 . The driven pulley of claim 2 , wherein for each roller assembly of the at least one roller assembly:
the at least one ramp comprises a first ramp and a second ramp;
in response to the movable sheave rotating relative to the fixed sheave in a first direction, the roller abuts the first ramp; and
in response to the movable sheave rotating relative to the fixed sheave in a second direction, the roller abuts the second ramp.
4 . A driven pulley for a continuously variable transmission comprising:
a fixed sheave;
a movable sheave operatively connected to the fixed sheave, the movable sheave being movable axially relative to the fixed sheave;
a spring biasing the movable sheave axially toward the fixed sheave; and
at least one roller assembly connected to one of the fixed sheave and the movable sheave,
another one of the fixed sheave and the movable sheave having at least one ramp configured for abutting the at least one roller assembly;
each roller assembly of the at least one roller assembly having:
a pin defining a radially extending pin axis, the pin having:
a first pin portion received in an aperture defined in the one of the fixed sheave and the movable sheave;
a second pin portion extending radially from the one of the fixed sheave and the movable sheave; and
an annular flange disposed radially between the first pin portion and the second pin portion, the flange having a first annular width, the flange abutting a surface of the one of the fixed sheave and the movable sheave surrounding the aperture; and
a roller disposed on the second pin portion, the roller being rotatable about the pin axis, the roller being slidable radially along the second pin portion, the roller having at least one annular portion, the at least one annular portion of the roller having a second annular width,
the first annular width being at least half of the second annular width.
5 . The driven pulley of claim 1 , wherein for each roller assembly of the at least one roller assembly:
the first pin portion is longer than the second pin portion.
6 . The driven pulley of claim 5 , wherein for each roller assembly of the at least one roller assembly:
the first annular width is at least 90 percent of the second annular width.
7 . The driven pulley of claim 1 , wherein for each roller assembly of the at least one roller assembly a spring pin is inserted through the first pin portion of the pin and the one of the fixed sheave and the movable sheave.
8 . A driven pulley for a continuously variable transmission comprising:
a fixed sheave;
a movable sheave operatively connected to the fixed sheave, the movable sheave being movable axially relative to the fixed sheave;
a spring biasing the movable sheave axially toward the fixed sheave; and
at least one roller assembly connected to one of the fixed sheave and the movable sheave,
another one of the fixed sheave and the movable sheave having at least one ramp configured for abutting the at least one roller assembly;
each roller assembly of the at least one roller assembly having:
a pin defining a radially extending pin axis, the pin having:
a first pin portion received in an aperture defined in the one of the fixed sheave and the movable sheave,
the first pin portion having a threaded portion and an unthreaded portion,
the unthreaded portion being disposed radially between the threaded portion and the flange;
a second pin portion extending radially from the one of the fixed sheave and the movable sheave; and
an annular flange disposed radially between the first pin portion and the second pin portion, the flange having a first annular width, the flange abutting a surface of the one of the fixed sheave and the movable sheave surrounding the aperture; and
a roller disposed on the second pin portion, the roller being rotatable about the pin axis, the roller having at least one annular portion, the at least one annular portion of the roller having a second annular width,
the first annular width being at least half of the second annular width.
9 . The driven pulley of claim 8 , wherein for each roller assembly of the at least one roller assembly:
a radius of the threaded portion is smaller than a radius of the unthreaded portion.
10 . The driven pulley of claim 8 , wherein for each roller assembly of the at least one roller assembly:
the unthreaded portion is press-fit in the aperture.
11 . The driven pulley of claim 1 , wherein:
the at least one roller assembly is connected to the fixed sheave; and
the movable sheave has the at least one ramp.
12 . The driven pulley of claim 11 , wherein for each roller assembly of the at least one roller assembly:
the second pin portion is radially inward of the first pin portion.
13 . The driven pulley of claim 11 , wherein:
the movable sheave has a hub defining the at least one ramp;
the hub extends in the fixed sheave; and
for each roller assembly of the at least one roller assembly, the roller is disposed radially between the flange and the hub, and the roller is radially inward of the flange.
14 . The driven pulley of claim 13 , wherein for each roller assembly of the at least one roller assembly:
a radial distance between a free end of the second pin portion and the hub is less than a height of the roller.
15 . The driven pulley of claim 1 , wherein for each roller assembly of the at least one roller assembly:
the flange has a flange outer radius;
the roller has a roller outer radius; and
the flange outer radius is at least half of the roller outer radius.
16 . The driven pulley of claim 15 , wherein for each roller assembly of the at least one roller assembly:
the flange outer radius is at least 90 percent of the roller outer radius.
17 . The driven pulley of claim 15 , wherein for each roller assembly of the at least one roller assembly:
the flange outer radius is at least 70 percent of a height of the roller.
18 . The driven pulley of claim 1 , wherein the at least one roller assembly is two roller assemblies disposed opposite each other.
19 . A continuously variable transmission comprising:
a drive pulley;
the driven pulley of claim 1 ; and
a belt looped around the drive and driven pulleys.
20 . A powertrain for a vehicle comprising:
a motor having a motor shaft;
the continuously variable transmission of claim 19 , the drive pulley being operatively connected to and driven by the motor shaft; and
a driveshaft operatively connected to and driven by the driven pulley.