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Variable Speed Belts
Jason Variable Speed belts are for use on variable speed pulley drives requiring exact speed
control and maximum range of speed changes. Variable speed drives are employed where the
operating speed of the driven pulley must vary over a wider range. Axial movement of the
variable speed pulley flange changes the pitch diameter (radial position) of the belt and
therefore belt speed, and so the rotational speed of the driven pulley. The sidewalls of the belt conform to the
angular faces of the pulley flanges.
A variable speed drive may consist of either one or two pulleys with moveable flanges. In a drive with only one
pulley having a single moveable flange, the center distance is changed to force the belt to move radially. For a
drive using two pulleys, each having a moveable flange(s), one pulley's flange works against a spring, which
allows the flange to move axially and change the radial position of the belt. The other pulley is mechanically
opened or closed using axial force. The axial force applies a radial pressure to the angled sides of the belt and
causes radial movement. On the spring pulley, the force from the belt sidewall forces the spring outward and
opens the flanges or allows it to move inward and close. This changes the pitch diameter of the belt and the rota-
tional speed of the driven shaft. Two pulley systems usually provide a wider speed range than a single variable
speed pulley drive.
American Variable Speed (ARPM) belts are specified by top width, the pulley groove angle and pitch length. The
groove angle can be measured from the drive pulleys
- Example: 3236V369
PART NUMBER DESIGNATION
3236V369
32 =
Top width in sixteenths of an inch = 32/16
(or 2 inches)
36 =
Intended sheave angle = 36 degree sheave angle
V =
Variable Speed Belt
369 =
Pitch length in tenths of an inch = 36.9"
(369 = 36.9 x 10)
Features & Benefits
l
High Modulus Tensile Members
- Ensures minimum stretch and excellent belt length stability
l
Raw Edge Sidewalls
- Provides maximum grip and smooth, quiet performance
l
Oil & Heat Resistant
- Delivers excellent durability in harsh environements
l
Chloroprene Rubber Compound
- Excellent resistance to wear
Construction
Compound
- Chloroprene
Cord
- High Modulus
Sidewalls
- Raw Edge
Applications -
General Industry, Agricultural, Machine Tools
Engineering Standards -
American Standard Sizes - conform to ARPM/RMA standard IP-25
ISO Variable Speed Sizes - conform to ISO R1604 standard
VARIABLE SPEED BELTS
POWERING GLOBAL INDUSTRY
VARIABLE SPEED BELTS
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