US 7,509,197 B2
Retarding system implementing transmission control
James W. Landes, East Peoria, Ill. (US); Mark E. Rettig, Peoria, Ill. (US); and Ryan E. Graham, Peoria, Ill. (US)
Assigned to Caterpillar Inc., Peoria, Ill. (US)
Filed on Jan. 31, 2005, as Appl. No. 11/45,297.
Prior Publication US 2006/0173599 A1, Aug. 03, 2006
Int. Cl. G06F 17/00 (2006.01); G06F 19/00 (2006.01); B60W 10/04 (2006.01); B60W 10/10 (2006.01); G06F 7/00 (2006.01); F16H 59/60 (2006.01)
U.S. Cl. 701—50  [701/54; 701/53; 701/93; 477/37; 477/109; 477/115; 477/98; 477/120; 477/156; 477/186; 477/119; 477/94; 74/625; 74/114; 74/335; 74/473.11; 74/473.21] 21 Claims
OG exemplary drawing
 
1. A retarding system for a machine having a power source, a transmission, and a manually operated braking mechanism, comprising:
an engine retarder associated with the power source; and
a controller in communication with the transmission, the manually operated braking mechanism, and the engine retarder, the controller being configured to:
determine a deceleration rate of the machine and compare the deceleration rate of the machine to a predetermined threshold rate;
determine if the manually operated braking mechanism is active;
cause the transmission to downshift if the deceleration rate is less than the predetermined threshold rate and the manually operated braking mechanism is determined to be active; and
prevent the transmission from downshifting if the deceleration rate is less than the predetermined threshold rate and the manually operated braking mechanism is determined to be inactive.