Machine element or mechanism – Rotary member or shaft indexing – e.g. – tool or work turret – Preselected indexed position
Patent
1986-12-02
1988-03-22
Wright, Dirk
Machine element or mechanism
Rotary member or shaft indexing, e.g., tool or work turret
Preselected indexed position
3644241, 192 0052, 192 009, 192 0075, B60K 4118
Patent
active
047320559
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to a shift control apparatus for an automatic transmission system of a type in which the stroke of a friction clutch interposed between an engine of a vehicle and a transmission is electronically controlled through an actuator, and the meshing position of the gears of the transmission is also electronically controlled through gear position change-over means.
BACKGROUND ART
For the purpose of alleviating the driver's effort to maneuver a large-sized truck, bus or the like, an automatic transmission system capable of automatically selecting the gear position depending on the running condition of the vehicle has been proposed.
Conventional automatic transmission systems are exclusively designed for use in small-sized passenger cars.
This automatic transmission system has generally such a structure that a fluid coupling such as a hydraulic torque converter is interposed between an engine and a planetary gear type transmission controlled by hydraulic pressure, and the gear position of the planetary gear type transmission is changed over by gear position change-over means.
An important matter to be taken into consideration for the development of an automatic transmission system suitable for application to a large-sized truck or the like is that the number of production of vehicles of this kind is very small as compared to that of passenger cars. Therefore, newly designing an expensive torque converter or the like is quite disadvantageous from the aspect of cost, and it is desirable that the existing drive system including the friction clutch and transmission as well as the existing production equipment, can be directly utilized for the production without any alteration.
DISCLOSURE OF INVENTION
It is a primary object of the present invention to provide a shift control apparatus for an automatic transmission system, which can automatically achieve a smooth speed shift under electronic control in spite of the fact that the existing drive system is directly used without any alteration.
In accordance with the present invention, there is provided a shift control apparatus for an automatic transmission system comprising a clutch coupled to an output shaft of an engine; a parallel-shaft type gear transmission coupled at its input shaft to the clutch; a clutch actuator actuating engagement and disengagement of the clutch; actuator control means for controlling the operation of the actuator; clutch position detecting means for detecting engagement and disengagement of the clutch; shift position detecting means for generating a signal indicating of the shift position of the parallel-shaft type gear transmission; shift position change-over means for changing the meshing state of the parallel-shaft type gear transmission; operating condition detecting means for detecting the operating condition of the vehicle; and automatic shift control means including map selecting means for selecting a map from among a plurality of maps representing optimum speed ratios determined on the basis of signals applied from the operating condition detecting means and indicative of at least the speed of the vehicle and the position of an accelerator pedal, the map being selected depending on whether a brake device is operated or not, optimum speed ratio determining means for determining an optimum speed ratio on the basis of the map selected by the map selecting means and according to the signals indicative of at least the vehicle speed and accelerator position applied from the operating condition detecting means, coincidence judging means for judging as to whether or not the shift position detected by the shift position detecting means coincides with the optimum speed ratio determined by the optimum speed ratio determining means, and shift position selecting means for applying a shift signal to the shift position change-over means so as to shift the parallel-shaft type gear transmission to the optimum shift position when non-coincidence is judged by the coincidence judging means.
The clutch is operat
REFERENCES:
patent: 3756358 (1973-09-01), Espenschied et al.
patent: 4194608 (1980-03-01), Usui et al.
patent: 4262783 (1981-04-01), Scarrott et al.
patent: 4529072 (1985-07-01), Oguma et al.
patent: 4614258 (1986-09-01), Fukunaga
patent: 4618043 (1986-10-01), Hattori et al.
patent: 4629045 (1986-12-01), Kasai et al.
patent: 4643048 (1987-02-01), Hattori et al.
patent: 4653352 (1987-03-01), Nakao et al.
"Electronically Controlled Automated Five-Speed Transmission", Automotive Engineering, 3/84, pp. 77-79.
Fukushima Shigeki
Iwamoto Tomoyuki
Tateno Toshiaki
Mitsubishi Jidosha Kogyo Kabushiki Kaisha
Wright Dirk
LandOfFree
Shift control apparatus for automatic transmission system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Shift control apparatus for automatic transmission system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Shift control apparatus for automatic transmission system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-435939