TM 5-2420-230-24-1
1. PRODUCT DEFINITION
EGS stands for Electronic Gear Selector.
The EGS is designed to control the selected gear in a powershift transmission.
It distinguishes itself from conventional shift levers by it's flexibility (customer's need) and it's ability to
protect the complete driveline from driver's abuse.
The EGS integrates a complete microcomputer and an indicator display (using bi-coloured LED's) into
the shift lever housing.
Possible features include :
Functionally replaces all existing CLARK-HURTH shift levers
Direction reversal protection
Downshift protection
Automatic powerup in neutral
Neutral start protection
Automatic Lockup
Shift sequencing
Kickdown function
Speedo-meter output
Neutral lock function
Declutch function
Speed limitation
... etc.
These functions can be implemented through use of dedicated software programs for the internal
microcomputer.
2. FUNCTIONAL DESCRIPTION
The EGS has a mechanical shift lever which passes information (contactless) to the computer.
This information together with acquired vehicle speed (by using a speed sensor ) is used to shift to the
requested gear or to prevent this, while indicating this on the shift lever's display.
The computer system receives information from 4/5 internal inputs (shift lever and kickdown button, if
used), 2 external ON/OFF inputs, and a speed sensor input channel.
This information is used to control up to 8 power switches (which control the transmission and other
functions) and a speedometer output.
EGS user manual. Page 2 of 25
SPICER CLARK-HURTH
Document reference : egsman4.doc
Revision date: 07/04/97
Ten Briele 3, 8200 Brugge, Belgium
Tel: +32/50/402445
Fax: +32/50/402402
G-4
