Method of pulley manufacture and product
AssigneeDrive Manufacturing Inc.
InventorKlaus K. Bytzek
Life of this patent
Estimating the term…
Abstract
This invention relates to a novel method of making pulleys and pulley blanks from sheet metal. The sheet metal is stamped into pulley blanks having an upstanding cylindrical wall, the cylindrical wall is then thickened by being partially collapsed axially, followed by contacting with a roller. The roller can have a plurality of v-shaped grooves on its surface, to form a pulley for use with a poly-v belt.
Claims13
A poly v pulley formed from a pulley can blank of sheet metal of a predetermined minimum permissible thickness comprising:
- a circular base of a wall thickness equal to said predetermined minimum permissible thickness, and
- an integral annular wall portion having a generally smooth cylindrical interior peripheral surface and an exterior peripheral surface shaped to operatively engage a poly v-belt,
- said wall portion having a cross-sectional configuration defined by metal cold flow which is straight along its interior periphery and has a plurality of v grooves in its exterior periphery,
- the distance between the trough of each v groove and said straight interior periphery being sufficient to provide required strength but less than the predetermined minimum thickness of said sheet metal can blank,
- the cross-sectional area of said wall portion being greater than the cross-sectional area of a section of said sheet metal can blank of said predetermined thickness having a length equal to the axial extent of said wall portion whereby said pulley contains less metal and weighs less than a pulley with a similarly configured wall portion made from a can blank of the same metal having a thickness such that a length thereof equal to the axial extent of said wall portion has a cross-sectional area equal to or slightly greater than the cross-sectional area of said wall portion.
In a method of making a pulley from a pulley can blank of sheet metal of a predetermined minimum permissible thickness in which a circular base is formed from said pulley can blank with a thickness equal to said predetermined minimum permissible thickness, the improvement which comprises
- forming integral with said base a thickened annular wall portion from said pulley can blank which has a thickness greater than said predetermined minimum thickness, said thickened wall portion being formed by
- partially collapsing an annular section of the pulley can blank having an axial extent greater than the axial extent of said annular wall portion to an axial extent equal to that of said annular wall portion without materially changing the thickness thereof but not completely such that interior surface portions thereof are interengaged, and
- moving the partially collapsed section of the pulley can blank radially inwardly while restraining the same against axial expansion and radially inward movement beyond a predetermined radial position so that the interior peripheral surface area of said partially collapsed section is reduced without portions thereof interengaging.
Dependencies are inferred from the claim text.