Shift lever assembly for minimizing jumpout
AssigneeEaton Corporation
InventorJohn J. Bair
Life of this patent
Estimating the term…
Abstract
A directly mounted shift lever assembly (30) for a manually shifted vehicular transmission (16) for minimizing shift lever-induced jumpout. A counterweight (52) is mounted to the shift lever (31) in a forwardly extending manner to move the center of gravity (CG) of the resultant shift lever assembly forward of the shift lever Y--Y pivot axis (34).
Claims4
A shift lever assembly (30) for reducing shift lever-induced jumpout in a manually shifted transmission system comprising:
- a shift lever subassembly (31) associated with a manually shifted vehicular transmission having an output shaft, said shift lever subassembly comprising an elongated shift lever having a shift knob at one end thereof and pivotably mounted about a pivot axis defined in a shift tower mounted directly to the transmission for generally fore-and-aft pivotable movement to selectively engage and disengage selected transmission ratios, said shift lever subassembly having a center of gravity located rearwardly of a plane (44) containing said pivot axis and perpendicular to the axis of said output shaft;
- and
- a counterweight (50) attachable to said shift lever at a location intermediate said shift knob and said pivot axis and including a forwardly extending mass, said counterweight and said shift lever subassembly forming a resultant shift lever assembly (30), said mass being of sufficient magnitude and of sufficient forward extension to offset the center of gravity of said resultant shift lever assembly to a position forward of said plane.
A method for providing a shift lever assembly (30) for a manually shifted vehicular transmission having an output shaft, said shift lever assembly comprising an elongated shift lever (31) having a shift knob at one end thereof and pivotably mounted about a pivot axis defined in a shift tower mounted directly to the transmission for generally fore-and-aft pivotable movement to selectively engage and disengage selected transmission ratios, said shift lever assembly is considered to be subjected to vertical accelerations (a.sub.Y) and angular acclerations about said pivot axis (.varies.), which are related in a known manner, said method comprising:
- providing a mass (50) extending forwardly from said shift lever from a position intermediate said shift knob and said pivot axis for offsetting the center of gravity of said shift lever assembly forwardly of a plane (44) containing said pivot axis and perpendicular to the axis of said output shaft, said mass selected to provide a shift lever assembly center of gravity which will reduce the value of the expression I.varies.-a.sub.Y Mx where:
- I=moment-of-inertia of shift lever assembly;
- .varies.=angular acceleration of shift lever assembly in counterclockwise direction about said pivot axis;
- a.sub.Y =vertical upward acceleration;
- M=mass of shift lever assembly;
- and
- x=distance between center of gravity and said plane.
Dependencies are inferred from the claim text.