Patent ID: 6626036
Filing Date: 2003-09-30
Classification: F16D,F16H

Abstract:
A method for calibrating hydraulic clutches in a powershift transmission of a work vehicle, comprising the steps of:manually connecting a pressure transducer to a first hydraulic fluid conduit extending between a first clutch control valve and a first clutch in the powershift transmission such that the pressure transducer generates an electronic pressure signal indicative of the fluid pressure in the first clutch; manually connecting the pressure transducer to an electronic transmission controller on the vehicle, wherein the electronic transmission controller is configured to drive the pressure transducer and to receive the electronic pressure signal; electronically signaling the first clutch valve to fill the first clutch with hydraulic fluid; electronically monitoring the time required to fill the first clutch; determining that the digital value indicative of a current clutch pressure signal is greater than the digital value indicative of at least one past dutch pressure signal by a predetermined pressure difference; recording a digital value indicative of the time required to fill the first clutch in an electronic memory of the electronic transmission controller, manually disconnecting the first pressure transducer from the first conduit; and manually disconnecting the first pressure transducer from the electronic transmission controller, wherein the step of manually connecting to a first conduit includes the step of fluidly coupling the first pressure transducer to a quick-connect coupling mounted on the transmission, wherein the pressure transducer is electrically connected to a first electrical connector such that the transducer and connector together define a removable and replaceable structure and further wherein the step of connecting to the controller includes the step of coupling the first electrical connector to a mating electrical connector on the work vehicle, wherein the mating electrical connector is electrical coupled to the electronic transmission controller, wherein the step of electronically monitoring includes the step of comparing a digital value indicative of a current clutch pressure signal provided by the pressure transducer with a digital value indicative of at least one past clutch pressure signal provided by the pressure transducer, wherein the step of comparing includes the step of determining that the digital value indicative of a current clutch pressure signal is greater than the digital value indicative of at least one past clutch pressure signal by a predetermined pressure difference, and wherein the step of electronically storing includes the steps of: calculating a digital elapsed time value in the electronic transmission controller indicative of the elapsed time from the step of electronically signaling to the time of the step of determining; and saving the digital elapsed time value in the electronic transmission controller, the method further comprising the step of subtracting a predetermined time interval from the digital elapsed time value to generate a reduced digital elapsed time value, and saving the reduced digital elapsed time value in the electronic transmission controller.