Interrelated power delivery controls – including engine control – Transmission control – With clutch control
Patent
1995-12-07
1997-01-21
Wright, Dirk
Interrelated power delivery controls, including engine control
Transmission control
With clutch control
477 91, B60K 4102, F16H 6104
Patent
active
055955509
DESCRIPTION:
BRIEF SUMMARY
This invention relates to a clutch control system for the automatic control of a motor vehicle clutch which connects an engine with a gearbox under the control of a driver-operated gear ratio selector lever, the control system controlling both initial clutch take-up on starting of the vehicle, clutch re-engagement following each ratio change, clutch disengagement on movement of the gear selector lever to change the operative ratio of the gearbox, and clutch disengagement on the coming to rest etc. of the vehicle. Such a clutch control system is herein after referred to as a clutch control system of the kind specified.
Examples of such systems are described in the Applicants earlier European patents Nos 0038113, 0043660, 0059035 and 0101220 and European Application No 0566595.
Problems can arise with such systems if, with the vehicle stationary, the operator moves the gear selector lever to select the initial drive take-up ratio and finds his movement of the gear selector lever baulked by the non-alignment of the gear teeth to be engaged in the gearbox.
It is an object of the present invention to overcome the above baulking problem.
Thus according to the present invention there is provided a clutch control system of the kind specified in which, if the gear lever is in the neutral position, an anti-baulking routine is enabled which allows engagement of the clutch by increasing the engine speed above an idle level.
Typically the clutch will be arranged to be fully engaged at an engine speed of say 1500 r.p.m. and by temporarily increasing engine speed with the gearbox in neutral the relevant gears can be spun so that any baulking situation which exists will be removed.
The system ensures that with the engine idling the clutch is disengaged thus preventing idle rattle.
The level of clutch engagement achieved by the anti-baulking routine may be proportional to the actual engine speed or to the position of the accelerator pedal or hand throttle lever or butterfly throttle valve (or diesel injector pump setting) or to a combination of one or more of these parameters as appropriate.
The clutch engagement cycle when in neutral may operate with hysteresis so that, for example, engagement commences at 1000 r.p.m. and is completed by 1500 r.p.m. whilst subsequent clutch disengagement does not begin until 1000 r.p.m. and is not completed until 800 r.p.m. This hysteresis feature is particularly helpful since it allows engine driven accessories to be operated with the engine speed being controlled via the accelerator or a hand throttle control. The progressive clutch engagement with increasing engine speed ensures a soft start for any such accessories.
One embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:
FIG. 1 shows in diagrammatic form the general layout of a clutch control system of the kind specified embodying the present invention, and
FIG. 2 is a data flow diagram of the anti-baulking routine of the present invention.
Referring to FIG. 1 this shows an engine 10 and a gearbox 12 coupled through a friction clutch 14, via a gearbox input shaft 15. Fuel is supplied to the engine by a throttle 16 which includes a throttle valve 18 operated by accelerator pedal 19. The clutch 14 is actuated by release fork 20, which is operated by a slave cylinder 22. The gearbox is controlled by a gear ratio selector lever 24 which is connected with the gearbox via selector linkage 25 and which includes a load-sensing switch means 33 which detects forces applied to the lever 24 by the driver and produces a signal Vs indicating an intention to change gear.
A control unit 36 controls the actuation of the clutch 14 via an hydraulic control 38 which controls the operation of slave cylinder 22. Control unit 36 receives signals Vs from gear lever 24 and signals Ve proportional to engine speed from engine speed sensor 26. Signals Vt from throttle valve position sensor 30 proportional to the current throttle opening and accelerator pedal position signals Va
REFERENCES:
patent: 4324322 (1982-04-01), Sibeud
patent: 4727472 (1988-02-01), Deutsch et al.
patent: 4899623 (1990-02-01), Wokan et al.
Jarvis Roger P.
Jones Charles J.
Automotive Products plc
Germain Lee A.
Milliken Paul E.
Wright Dirk
LandOfFree
Clutch control 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 Clutch control system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clutch control system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2321173