Patent ID: 7861612
Filing Date: 2011-01-04
Classification: F16H,Y10T

Abstract:
1. A range selection control system for a multispeed compound transmission facilitating the safe engagement and disengagement and operation of a power take off, the system having both fluid control elements and electrical control elements for use with a source of pressurized fluid and electrical power and comprising: a range cylinder having a range cylinder first end and a range cylinder second end; a fluid actuated range piston assembly slideably disposed within the range cylinder for movement between a low range position at the first end of the range cylinder and a high range position at the second end of the range cylinder and having a range engagement feature in the range piston assembly, the range cylinder and the range piston assembly defining a sealed high range chamber between the first end of the range cylinder and a first surface of the piston assembly and also defining a sealed low range chamber between the second end of the range cylinder and a second side of the piston assembly; a neutral cylinder intersecting the range cylinder having a first neutral cylinder end opposite the range cylinder; a fluid actuated neutral piston assembly slideably disposed within the neutral cylinder defining a neutral chamber between the first neutral cylinder end and a neutral piston assembly end facing the first neutral cylinder end, the neutral piston assembly engaging the range control piston assembly responsive to pressurization of the neutral chamber, the neutral piston assembly being received at least in part by the engagement feature when the range control piston assembly is in a neutral position between the low range position and the high range position, and the neutral piston assembly and neutral the cylinder together retaining the piston assembly in the neutral position; and an electrically responsive locking mechanism in selective locking engagement with the neutral piston assembly when the neutral piston assembly is received by the range engagement feature with the selective locking engagement being controlled by a condition of an electrical switch indicative of a transmission condition.