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US 4,380,048 AGranted
Shift control system for a vehicle automatic transmission
AssigneeNissan Motor Co., Ltd.
InventorsNorimasa Kishi, Tadashi Suzuki
Life of this patent
Estimating the term…
Abstract
At each of a plurality of sub-time intervals within a fixed time interval, the speed and the throttle opening are accumulated sequentially. Averaged values of the speed and the throttle opening derived at every fixed time interval are used together with an averaged associated acceleration to select a correct shift pattern well matched to an actual running condition of the vehicle.
Claims12
In a shift control system for an automatic transmission of the type having a plurality of predetermined shift characteristics and of the type for use in an engine powered vehicle, wherein said shift control system includes:
- engine load sensor means for producing a signal corresponding to an engine load of a vehicle;
- vehicle speed sensor means for producing a signal corresponding to a vehicle speed;
- and means for providing a signal indicative of the presently selected one of the shift characteristics of the transmission;
- the improvement comprising:
- deriving means responsive to the signal from said engine load sensor means for deriving an averaged value of the engine load during a predetermined time interval for each of a succession of said predetermined time intervals;
- and responsive to the signal from said vehicle speed sensor means for deriving an averaged value of the vehicle speed during said predetermined time interval for each time interval and for deriving an actual acceleration during each time interval;
- means responsive to the signals from said deriving means indicative of the average value of the engine load and the average value of the vehicle speed and a signal from said signal indicator means indicative of the presently selected shift characteristic of the automatic transmission for determining a programmed acceleration as a function of said averaged engine load, said averaged vehicle speed, and the presently selected shift characteristic;
- and means responsive to said so-determined programmed acceleration and said actual acceleration for comparing them to each other and discriminating whether or not another one of the transmission shift characteristics is to be selected.
5 more elements
In a shift control system for an automatic transmission of the type having a plurality of predetermined transmission shift characteristics and of the type for use in an engine powered vehicle, wherein said shift control system includes:
- engine load sensing means for providing a signal responsive to engine load;
- vehicle speed sensing means for providing a signal responsive to vehicle speed;
- and means coupled to the transmission for providing a signal indicative of the presently selected one of the transmission shift characteristics of the transmission;
- the improvement comprising:
- means connected to said engine load sensing means and said vehicle speed sensing means for determining, respectively, the average value of the engine load and the vehicle speed during each of a succession of predetermined time intervals and for determining the actual vehicle acceleration during each of the succession of predetermined time intervals;
- storage means having predetermined vehicle acceleration data stored therein as a function of average engine load, average vehicle speed, and the transmission shift characteristic;
- means connected to said storage means and responsive to the so-determined average engine load, vehicle speed, and indicated transmission shift characteristic for obtaining at least one of said predetermined vehicle acceleration values stored as a function of said average engine load, vehicle speed, and indicated transmission shift characteristic;
- and
- comparing means for comparing the actual vehicle acceleration and the predetermined acceleration value obtained from said storage means and discriminating whether or not another one of the transmission shift characteristics is to be selected as a function of the comparison.
6 more elements
In a shift control system for an automatic transmission of the type having a plurality of predetermined shift characteristics and of the type for use in an engine powered vehicle, wherein said shift control system includes:
- engine load sensor means for producing a signal corresponding to an engine load of a vehicle;
- vehicle speed sensor means for producing a signal corresponding to a vehicle speed;
- and means for providing a signal indicative of the presently selected one of the shift characteristics of the transmission;
- the improvement comprising:
- means (1) responsive to the signal from said engine load sensor means for deriving an averaged value of the engine load during a predetermined time interval for each of a succession of said predetermined time intervals, (2) responsive to the signal from said vehicle speed sensor means for deriving an averaged value of the vehicle speed during said predetermined time interval for each time interval, (3) responsive to the derived averaged values of engine load and vehicle speed and the signal indicative of the presently selected shift characteristic of the automatic transmission for determining a programmed acceleration as a function of said averaged engine load, said averaged vehicle speed, and the presently selected shift characteristic, (4) responsive to the signal indicative of the vehicle speed from said vehicle speed sensor means for deriving an actual acceleration during each of said predetermined time intervals, and (5) responsive to said so-determined programmed acceleration and said actual acceleration for comparing them to each other and discriminating whether or not another one of the predetermined transmission shift characteristics is to be selected.
2 more elements
A shift control system for an automatic transmission of the type having a plurality of predetermined transmission shift characteristics and of the type for use in an engine powered vehicle, wherein said shift control system includes:
- engine load sensing means for providing a signal responsive to engine load;
- vehicle speed sensing means for providing a signal responsive to vehicle speed;
- means coupled to the transmission for providing a signal indicative of the presently selected one of the transmission shift characteristics of the transmission;
- the improvement comprising:
- storage means having predetermined vehicle acceleration data stored therein as a function of average engine load, average vehicle speed, and the transmission shift characteristics;
- means connected to said engine load sensing means, said vehicle speed sensing means and said storage means (1) for determining, respectively, the average value of the engine load and the vehicle speed during each of a succession of predetermined time intervals, (2) for determining the actual vehicle acceleration during each of the succession of predetermined time intervals, (3) responsive to the so-determined average engine load, vehicle speed, and indicated transmission shift characteristic for obtaining at least one of said predetermined vehicle acceleration values stored as a function of said average engine load, vehicle speed, and indicated transmission shift characteristic, and (4) for comparing the actual vehicle acceleration and the predetermined acceleration value obtained from said storage means and discriminating whether or not another one of the transmission shift characteristics is to be selected as a function of the comparison.
3 more elements
Dependencies are inferred from the claim text.