Engine brake running control for automatic transmission in automatic drive range

Claim 1

An engine brake running control system for an automotive vehicle including a brake pedal, and an automatic transmission, the automatic transmission being shiftable to a predetermined gear position when the automatic transmission operates in a predetermined automatic drive range, the engine brake running control system comprising: means for detecting a depression of the brake pedal and generating a brake pedal depression indicative signal indicative of said depression of the brake pedal; means for detecting a present gear position which the automatic transmission is conditioned in and generating a present gear position indicative signal indicative of said present gear position detected; means for selecting, out of a predetermined group of gear positions including the predetermined gear position, a new gear position lower than said present gear position in accordance with said preset gear position indicative signal and at least one variable which the automotive vehicle is involved in as long said brake pedal depression indicative signal is generated when the automatic transmission operates in the predetermined automatic drive range; means for effecting a downshaft from said present gear position in the automatic transmission to said new gear position when the automatic transmission operates in the predetermined automatic drive range; means for conditioning the automatic transmission for engine brake running at said new gear position as long as said brake pedal depression indicative signal is generated when the automatic transmission operates in the predetermined automatic drive range; and means for preventing said conditioning means from conditioning the automatic transmission for engine brake running at the predetermined gear position when said brake pedal depression indicative signal disappears subsequently when the automatic transmission operates in the predetermined automatic drive range, wherein said selecting means include a first indicator indicative of a gear position higher than and.

Claim 22

A method for engine brake running control for an automotive vehicle including a brake pedal, and an automatic transmission, the automatic transmission being shiftable to a predetermined gear position when the automatic transmission operates in a predetermined automatic drive range, the method comprising the steps of: detecting a depression of the brake pedal and generating a brake pedal depression indicative signal indicative of said depression of the brake pedal; detecting a present gear position which the automatic transmission is conditioned in and generating a present gear position indicative signal indicative of said present gear position detected; selecting, out of a predetermined group of gear positions including the predetermined gear position, a new gear position lower than said present gear position in accordance with said present gear position indicative signal and at least one variable which the automotive vehicle is involved in as long as said brake pedal depression indicative signal is generated when the automatic transmission operates in the predetermined automatic drive range; effecting a downshift from said present gear position in the automatic transmission to said new gear position when the automatic transmission operates in the predetermined automatic drive range; conditioning the automatic transmission for engine brake running at said new gear position as long as said brake pedal depression indicative signal is generated when the automatic transmission operates in the automatic drive range; and preventing the automatic transmission from being conditioned for engine brake running at the predetermined gear position when said brake pedal depression indicative signal disappears subsequently when the automatic transmission operates in the predetermined automatic drive range.

Claim 23

A method for engine brake running control for an automotive vehicle including a brake pedal, and an automatic transmission, the automatic transmission being shiftable to a predetermined gear position when the automatic transmission operates in a predetermined automatic drive range, the method comprising the steps of: detecting a depression of the brake pedal and generating a brake pedal depression indicative signal indicative of said depression of the brake pedal; detecting a present gear position which the automatic transmission is conditioned in and generating a present gear position indicative signal indicative of said present gear position detected; selecting, out of a predetermined group of gear positions including the predetermined gear position, a new gear position lower than said present gear position in accordance with said present gear position indicative signal and at least one variable which the automotive vehicle is involved in as long as said brake pedal depression indicative signal is generated when the automatic transmission operates in the predetermined automatic drive range; effecting a downshift from said present gear position in the automatic transmission to said new gear position when the automatic transmission operates in the predetermined automatic drive range; conditioning the automatic transmission for engine brake running at said new gear position as long as said brake pedal depression indicative signal is generated when the automatic transmission operates in the automatic drive range; and preventing the automatic transmission from being conditioned for engine brake running at the predetermined gear position when said brake pedal depression indicative signal disappears subsequently when the automatic transmission operates in the predetermined automatic drive range.

Claim 24

A method for engine brake running control for an automotive vehicle including a brake pedal, and an automatic transmission, the automatic transmission being shiftable to a predetermined gear position in accordance with a predetermined shift schedule when the automatic transmission operates in a predetermined automatic drive range, the method comprising the steps of: detecting a demand for engine brake running of the automotive vehicle when the automatic transmission operates in the predetermined automatic drive range; detecting a present gear position which the automatic transmission is conditioned in; setting one of a first indicator and a second indicator in response to said present gear position detected and said demand for engine brake running, said first indicator being indicative of a gear position higher than and adjacent to the predetermined gear position, said second indicator being indicative of the predetermined gear position; comparing a gear position that is determined in accordance with the predetermined shift schedule and that gear position which is indicated by said one of said first or second indicators that is set and setting as a new gear position a lower one of said gear position that is determined in accordance with the predetermined shift schedule and that gear position which is indicated by said one indicator that is set; shifting the automatic transmission from said present gear position to said new gear position; conditioning the automatic transmission for engine brake running when one of said first and second indicators is set; detecting a release of the brake pedal after said demand for engine brake running has been detected; and resetting said second indicator when said release of the brake pedal is detected.

Claim 25

A method for engine brake running control for an automotive vehicle including a brake pedal, and an automatic transmission, the automatic transmission being shiftable to a predetermined gear position in accordance with a predetermined shift schedule when the automatic transmission operates in a predetermined automatic drive range, the method comprising the steps of: detecting a demand for engine brake running of the automotive vehicle when the automatic transmission operates in the predetermined automatic drive range; detecting a present gear position which the automatic transmission is conditioned in; setting one of a first indicator and a second indicator in response to said present gear position detected and said demand for engine brake running, said first indicator being indicative of a gear position higher than and adjacent to the predetermined gear position, said second indicator being indicative of the predetermined gear position; comparing a gear position that is determined in accordance with the predetermined shift schedule and that gear position which is indicated by said one of said first or second indicators that is set and setting as a new gear position a lower one of said gear position that is determined in accordance with the predetermined shift schedule and that gear position which is indicated by said one indicator that is set; shifting the automatic transmission from said present gear position to said new gear position; conditioning the automatic transmission for engine brake running when one of said first and second indicators is set; detecting a release of the brake pedal after said demand for engine brake running has been detected; and resetting said second indicator when said release of the brake pedal is detected.

Claim 26

A method for engine brake running control for an automotive vehicle including an automatic transmission, an accelerator pedal, and a foot brake, the automatic transmission including an input shaft and an output shaft and being automatically shiftable to a predetermined gear position when a forward drive range is selected, the method comprising the steps of: detecting whether the forward drive range is selected or not and generating a forward drive range selection signal indicative of the fact that the forward drive range is selected; detecting whether the accelerator pedal is released or not and generating an accelerator pedal release indicative signal indicative of the fact that the accelerator pedal is released; detecting whether the foot brake is depressed or not and generating a foot brake depression indicative signal indicative of the fact that the foot brake is depressed; detecting a velocity of the output shaft of the automatic transmission and generating a velocity indicative signal indicative of said velocity of the output shaft; determining out of said velocity indicative signal a deceleration which the automotive vehicle is subject to and generating a deceleration indicative signal indicative of said deceleration determined; detecting a present gear position which the automatic transmission is conditioned in and generating a present gear position indicative signal indicative of said present gear position detected; preparing a plurality of indicators including a first indicator and a second indicator, said first indicator being indicative of a gear position higher than and next adjacent to the predetermined gear position and said second indicator being indicative of the predetermined gear position; setting one indicator of said plurality of indicators in response to said present gear position indicative signal and said deceleration indicative signal when said forward drive range selection signal, said accelerator pedal release indicative signal, and said foot brake depression indicative signal are all present; resetting said second indicator in response to an absence of said foot brake depression indicative signal when said forward drive range selection signal and said accelerator pedal release signal are both present; and conditioning the automatic transmission for engine brake running in response to said one of said plurality of indicators which has been set.

Claim 27

A method for engine brake running control for an automotive vehicle including an automatic transmission, an accelerator pedal, and a foot brake, the automatic transmission including an input shaft and an output shaft and being automatically shiftable to a predetermined gear position when a forward drive range is selected, the method comprising the steps of: detecting whether the forward drive range is selected or not and generating a forward drive range selection signal indicative of the fact that the forward drive range is selected; detecting whether the accelerator pedal is released or not and generating an accelerator pedal release indicative signal indicative of the fact that the accelerator pedal is released; detecting whether the foot brake is depressed or not and generating a foot brake depression indicative signal indicative of the fact that the foot brake is depressed; detecting a velocity of the output shaft of the automatic transmission and generating a velocity indicative signal indicative of said velocity of the output shaft; determining out of said velocity indicative signal a deceleration which the automotive vehicle is subject to and generating a deceleration indicative signal indicative of said deceleration determined; detecting a present gear position which the automatic transmission is conditioned in and generating a present gear position indicative signal indicative of said present gear position detected; preparing a plurality of indicators including a first indicator and a second indicator, said first indicator being indicative of a gear position higher than and next adjacent to the predetermined gear position and said second indicator being indicative of the predetermined gear position; setting one indicator of said plurality of indicators in response to said present gear position indicative signal and said deceleration indicative signal when said forward drive range selection signal, said accelerator pedal release indicative signal, and said foot brake depression indicative signal are all present; resetting said second indicator in response to an absence of said foot brake depression indicative signal when said forward drive range selection signal and said accelerator pedal release signal are both present; and conditioning the automatic transmission for engine brake running in response to said one of said plurality of indicators which has been set.