Engine ignition timing for a clutch engagement control system

• US 4,792,902 A
• Filed: 12/12/1985
• Issued: 12/20/1988
• Est. Priority Date: 12/12/1985
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Motor Company
• Inventors: Heermann, Charles, Tobler, William E., Hrovat, Davorin
• Primary Examiner(s): Gruber, Felix D.
• Application Number:
  US06/808,186
• Time in Patent Office: 1,104 Days
• Field of Search: 364/424.1, 74/851, 74/860, 74/866, 123/419, 123/422, 192/0.052, 192/0.092, 192/3.28
• US Class Current: 701/105
• CPC Class Codes: B60W 2050/0052 Filtering, filters
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/104 Output speed
• CPC Class Codes: F02P 5/1455 by using a second control of the closed loop type dependent on pinking F02P5/152
• CPC Class Codes: F02P 5/1504 with particular means during a transient phase, e.g. acceleration, deceleration, gear change during starting F02P5/1506
• CPC Class Codes: F16H 61/0437 by using electrical signals F16H61/0403 and F16H61/061 take precedence
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A system and method for controlling the ignition timing of a spark ignition internal combustion engine in a driveline that includes a multiple speed ratio transmission, at least one of whose operating speed ratios depends on the engaged or disengaged state of a clutch, the rotating inertia of the engine, equivalent vehicle inertia, a spring associated with the stiffness of the axle, inherent structural damping, and a spark advance controller-filter, whose output advances and retards the spark timing of the engine in accordance with the magnitude of engine speed and transmission output speed according to a control algorithm, which improves speed ratio control during shifts and minimizes the underdamped oscillations that result after the clutch is fully engaged.

Claims

1. A method for controlling the operation of a powertrain that includes a spark ignition internal combustion engine, a multiple speed ratio transmission, means for commanding the speed ratios at which the transmission operates, a hydraulic clutch and a solenoid-operated valve that engages and disengages the clutch in accordance with a duty cycle applied to the solenoid, comprising:

producing a signal representing a commanded speed ratio SR_c ;

producing signals representing transmission output speed ω

_o and engine speed ω

_e ;

producing a commanded engine speed signal ω

_ec from the relationship ω

_ec =SR_c *ω

_o ;

producing an engine speed error signal Δ

ω

_e from the relationship Δ

ω

_e =ω

_ec -ω

_e ;

producing a duty cycle change signal Δ

M(k) from the engine speed error signal;

producing a current duty cycle signal M(k) by adding the current duty cycle change signal to a previous duty cycle signal M(k-1);

engaging or disengaging the clutch by applying to the solenoid-operated valve the current duty cycle signal;

retarding the engine ignition with respect to a nominal engine spark ignition according to the following relationship;

space="preserve" listing-type="equation">SA=K.sub.1 [I.sub.e ω

.sub.o d/dt(SR.sub.c)]+K.sub.2 (Δ

ω

.sub.e)+K.sub.2 d/dt(Δ

ω

.sub.e)

wherein d/dt is the differential with respect to time, I_e is the rotational inertia of the engine about the axis of the engine shaft, and K₁, K₂ and K₃ are gain constants.

2. The method of claim 1 further comprising:

passing the engine speed error signal through a PID filter to produce an output variable signal f(k); and

passing said output variable signal through a lead-lag filter to produce the duty cycle change signal Δ

M(k).

3. A method for controlling torsional vibrations in a powertrain that includes a spark ignition internal combustion engine, a multiple speed ratio transmission, means for commanding the speed ratios at which the transmission operates and a clutch driveably connecting the engine and the transmission comprising:

producing a signal representing a commanded speed ratio SR_c ;

producing a signal representing transmission output speed ω

_o ;

differentiating the commanded speed ratio with respect to time;

retarding the engine ignition with respect to a nominal engine spark ignition according to the following relationship;

space="preserve" listing-type="equation">SA.sub.1 =K.sub.1 [I.sub.e ω

.sub.o (d/dt) (SR.sub.c)]

wherein I_e is the rotational inertia of the engine about the axis of the engine shaft and K₁ is gain.

4. The method of claim 3 further comprising:

producing a signal representing engine speed ω

_e ;

calculating the commanded engine speed ω

_ec from the relationship ω

_ec =SR_c *ω

_o ;

calculating an engine speed error Δ

ω

_e from the relationship Δ

ω

_e =ω

_ec -ω

_e ;

retarding the engine ignition with respect to a nominal engine spark ignition according to the following relationship

space="preserve" listing-type="equation">SA=SA.sub.1 +K.sub.2 (Δ

ω

.sub.e)+K.sub.3 (d/dt)(Δ

ω

.sub.e)

wherein d/dt is the differential with respect to time and K₂ and K₃ are gain constants.