Control system/method for automated mechanical transmission systems

• US 5,487,004 A
• Filed: 10/29/1993
• Issued: 01/23/1996
• Est. Priority Date: 10/29/1993
• Status: Expired due to Fees

• Current Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Amsallen, Marcel
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US08/143,230
• Time in Patent Office: 816 Days
• Field of Search: 364/424.1, 364/424.01, 364/426.04, 477/78, 477/108, 477/120, 477/906, 477/115, 477/94, 477/148, 477/12.3, 477/808, 477/109, 477/127-129, 477/908, 477/131, 477/155, 477/133, 73/118.1, 74/337, 74/335, 74/339, 74/336 R, 74/357, 74/359, 74/360, 180/170, 192/3.31, 192/3.58, 324/546, 324/418, 324/422, 475/123
• US Class Current: 701/51
• CPC Class Codes: B60W 2510/105 Output torque
• CPC Class Codes: F16H 2059/144 characterised by change between positive and negative drive line torque, e.g. torque changes when switching between coasting and acceleration
• CPC Class Codes: F16H 2059/148 Transmission output torque, e.g. measured or estimated torque at output drive shaft
• CPC Class Codes: F16H 2061/1208 with diagnostic check cycles; Monitoring of failures
• CPC Class Codes: F16H 2061/1284 the failing part is a sensor
• CPC Class Codes: F16H 2302/04 Determining a modus for shifting
• CPC Class Codes: F16H 59/14 Inputs being a function of torque or torque demand
• CPC Class Codes: F16H 59/40 Output shaft speed
• CPC Class Codes: F16H 59/42 Input shaft speed
• CPC Class Codes: F16H 59/46 dependent on a comparison between speeds
• CPC Class Codes: F16H 59/48 Inputs being a function of acceleration
• CPC Class Codes: F16H 61/0213 characterised by the method for generating shift signals
• CPC Class Codes: F16H 61/0248 Control units where shifting is directly initiated by the driver, e.g. semi-automatic transmissions generation of movements for final actuating mechanisms F16H61/28
• CPC Class Codes: F16H 61/12 Detecting malfunction or potential malfunction, e.g. fail safe in control of hydrostatic gearing F16H61/4192; Circumventing or fixing failures
• CPC Class Codes: F16H 61/16 Inhibiting or initiating shift during unfavourable conditions, e.g. preventing forward reverse shift at high vehicle speed, preventing engine over speed unintentional control input F16H61/18
• CPC Class Codes: F16H 61/682 with interruption of drive
• CPC Class Codes: Y10T 74/19251 Control mechanism
• CPC Class Codes: Y10T 74/1926 Speed responsive
• CPC Class Codes: Y10T 74/19274 torque responsive
• CPC Class Codes: Y10T 74/194 Selective

Abstract

A control system (104)/method for a vehicular automated mechanical transmission is provided, which will compare input signals indicative of input shaft speed (IS) to the product of input signals indicative of output shaft speed multiplied by engaged gear ratio (OS*GR) to develop control parameters indicative of drivetrain torque magnitude and/or phase requiring a driveline torque transducer.

Claims

1. A control system (104) for at least partially automatic implementation of selected shifts of a mechanical change gear transmission system comprising a fuel throttle controlled engine (E), a multispeed change gear mechanical transmission (10) having an input shaft (16) and an output shaft (90)and having a plurality of selectably engageable gear ratios, a non-positive coupling (C) driving interposed between the engine and the transmission, a first sensor (98) for providing a first input signal (IS) indicative of input shaft rotational speed, a second sensor (100) for providing a second input signal (OS) indicative of output shaft rotational speed, a third sensor (70/110) for providing a third signal indicative of currently engaged transmission ratio, a non-manually controllable transmission actuator (112, 70, 96) for controlling shifting of the transmission, and a central processing unit (106) for receiving said first, second and third input signs and for processing same in accordance with predetermined logic rules to select and implement upshifts and downshifts from the currently engaged gear ratio and to issue command output signals to implement said upshifts and downshifts by the sequence of disengaging a first positive clutch and then engaging a second positive clutch, both of said positive clutches comprising a first clutch member (80, 82, 84) having a rotational speed determined by the rotational speed of the vehicle engine and a second clutch member (86, 88, 90) having a rotational speed determined by vehicle speed, said shift actuator having a first mode of operation wherein a maximum force is applied for disengaging said first positive clutch;

said central processing unit including;

logic rules effective for determining a value equal to a difference between said input signal indicative of input shaft rotational speed and the product of said input signal indicative of output shaft rotational speed multiplied by currently engaged transmission ratio, and if an absolute value of the difference between said first input signal and said product is less than a first reference value (|IS-(OS*GR)|<

REF₁) corresponding to an expected value of said absolute value in the absence of a fault in said first, second or third input signals, upon sensing a selection of a transmission shift from a currently engaged ratio, for (i) determining a presence or absence of conditions indicative of non-jaw clutch torque lock conditions if said absolute value of said difference is less than a second reference value equal to or less than 10 RPM (|IS-(OS*GR)|<

REF₂ ≦

10 RPM); and

(ii) for prohibiting issuing command output signals to said transmission actuator to cause disengagement of said currently engaged transmission ratio in said first mode of operation until it is determined that said conditions indicative of non-jaw clutch torque lock conditions are present.

2. The control system of claim 1 wherein it is determined that conditions indicative of non-jaw clutch torque lock conditions are present if the rate of change of the absolute value of said difference ((d/dt (|IS-(OS*GR)|)<

REF₂ <

0) is less than a second reference value having a negative value.

3. The control system of claim 1 wherein it is determined that conditions indicative of non-jaw clutch torque conditions are present if said difference changes from a positive to a negative value.

4. A control method for at least partially automatic implementation of selected shifts of a mechanical change gear transmission system comprising a fuel throttle controlled engine (E), a multispeed change gear mechanical transmission (10) having an input shaft (16) and an output shaft (90) and having a plurality of selectably engageable gear ratios, a non-positive coupling (C) drivingly interposed between the engine and the transmission, a first sensor (98) for providing a first input signal (IS) indicative of input shaft rotational speed, a second sensor (100) for providing a second input signal (OS) indicative of output shaft rotational speed, a third sensor (70/110) for providing a third signal indicative of currently engaged transmission ratio, a non-manually controllable transmission actuator (112, 70, 96) for controlling shifting of the transmission, and a central processing unit (106) for receiving said first, second and third input signals and for processing same in accordance with predetermined logic rules to select and implement upshifts and downshifts from the currently engaged gear ratio and to issue command output signals to implement said upshifts and downshifts by the sequence of disengaging a first positive clutch and then engaging a second positive clutch, both of said positive clutches comprising a first clutch member (80, 82, 84) having a rotational speed determined by the rotational speed of the vehicle engine and a second clutch member (86, 88, 90) having a rotational speed determined by vehicle speed, said shift actuator having a first mode of operation wherein a maximum force is applied for disengaging said first positive clutch;

said control method comprising;

determining a value equal to the difference between said input signal indicative of input shaft rotational speed and the product of said input signal indicative of output shaft rotational speed multiplied by currently engaged transmission ratio;

if an absolute value of a difference between said first input signal and said product is less than a first reference value (|IS -(OS*GR)|<

REF₁) corresponding to an expected value of said absolute value in the absence of a fault in said first, second or third input signals upon sensing a selection of a transmission shift from a currently engaged ratio, (i) determining a presence of conditions indicative of non-jaw clutch torque lock conditions if said absolute value of said difference is less than a second reference value equal to or less than 10 RPM (|IS -(OS*GR)|>

REF₂ <

10 RPM); and

(ii) prohibiting issuing command output signals to said transmission actuator to cause disengagement of said currently engaged transmission ratio in said first mode of operation until it is determined that said conditions indicative of non-jaw clutch torque lock conditions are present.

5. A control method for at least partially automatic implementation of selected shifts of a mechanical change gear transmission system comprising a fuel throttle controlled engine (E), a multispeed change gear mechanical transmission (10) having an input shaft (16) and an output shaft (90) and having a plurality of selectably engageable gear ratios, a non-positive coupling (C) drivingly interposed between the engine and the transmission, a first sensor (98) for providing a first input signal (IS) indicative of input shaft rotational speed, a second sensor (100) for providing a second input signal (OS) indicative of output shaft rotational speed, a third sensor (70/110) for providing a third signal indicative of currently engaged transmission ratio, a non-manually controllable transmission actuator (112, 70, 96) for controlling shifting of the transmission, and a central processing unit (106) for receiving said first, second and third input signals and for processing same in accordance with predetermined logic rules to select and implement upshifts and downshifts from the currently engaged gear ratio and to issue command output signals to implement said upshifts and downshifts by the sequence of disengaging a first positive clutch and then engaging a second positive clutch, both of said positive clutches comprising a first clutch member (80, 82, 84) having a rotational speed determined by the rotational speed of the vehicle engine and a second clutch member (86, 88, 90) having a rotational speed determined by vehicle speed, said shift actuator having a first mode of operation wherein a maximum force is applied for disengaging said first positive clutch;

said control method comprising;

determining a value equal to the difference between said input signal indicative of input shaft rotational speed and the product of said input signal indicative of output shaft rotational speed multiplied by currently engaged transmission ratio;

if an absolute value of a difference between said first input signal and said product is less than a first reference value (|IS -(OS*GR)|<

REF₁) corresponding to an expected value of said absolute value in the absence of a fault in said first, second or third input signal, upon sensing a selection of a transmission shift from a currently engaged ratio, (i) determining a presence of conditions indicative of non-jaw clutch torque lock conditions if said difference changes from a positive to a negative value; and

(ii) prohibiting issuing command output signals to said transmission actuator to cause disengagement of said currently engaged transmission ratio in said first mode of Operation until it is determined that said conditions indicative of non-jaw clutch torque lock conditions are present.

6. A control system (104) for at least partially automatic implementation of selected shifts of a mechanical change gear transmission system comprising a fuel throttle controlled engine (E), a multispeed change gear mechanical transmission (10) having an input shaft (16) and an output shaft (90) and having a plurality of selectably engageable gear ratios, a non-positive coupling (C) drivingly interposed between the engine and the transmission, a first sensor (98) for providing a first input signal (IS) indicative of input shaft rotational speed, a second sensor (100) for providing a second input signal (OS) indicative of output shaft rotational speed, third sensor means (70/110) for providing a third signal indicative of currently engaged transmission ratio, a non-manually controllable transmission actuator (112, 70, 96) for controlling shifting of the transmission, and a central processing unit (106) for receiving said first, second and third input signals and for processing same in accordance with predetermined logic rules to select and implement upshifts and downshifts from the currently engaged gear ratio and to issue command output signals to implement said upshifts and downshifts by the sequence of disengaging a first positive clutch and then engaging a second positive clutch, both of said positive clutches comprising a first clutch member (80, 82, 84) having a rotational speed determined by the rotational speed of the vehicle engine and a second clutch member (86, 88, 90) having a rotational speed determined by vehicle speed, said shift actuator having a first mode of operation wherein a maximum force is applied for disengaging said first positive clutch;

said control unit including;

logic rules effective, upon sensing a selection of a transmission shift from a currently engaged ratio, for (i) determining a presence of conditions indicative of non-jaw clutch torque lock conditions if an absolute value of a difference between said first input signal and a product of said second input signal multiplied by the currently engaged gear ratio is less than a reference value ((|IS-(OS*GR)|)>

REF); and

(ii) prohibiting issuing command output signals to said transmission actuator to cause disengagement of said currently engaged transmission ratio in said first mode of operation until it is determined that said conditions indicative of non-jaw clutch torque lock conditions are present.

7. A control system (104) for at least partially automatic implementation of selected shifts of a mechanical change gear transmission system comprising a fuel throttle controlled engine (E), a multispeed change gear mechanical transmission (10) having an input shaft (16) and an output shaft (90) and having a plurality of selectably engageable gear ratios, a non-positive coupling (C) drivingly interposed between the engine and the transmission, a first sensor (98) for providing a first input signal (IS) indicative of input shaft rotational speed, a second sensor (100) for providing a second input signal (OS) indicative of output shaft rotational speed, third sensor means (70/110) for providing a third signal indicative of currently engaged transmission ratio, a non-manually controllable transmission actuator (112, 70, 96) for controlling shifting of the transmission, and a central processing unit (106) for receiving said first second and third input signals and for processing same in accordance with predetermined logic rules to select and implement upshifts and downshifts from the currently engaged gear ratio and to issue command output signals to implement said upshifts and downshifts by the sequence of disengaging a first positive clutch and then engaging a second positive clutch, both of said positive clutches comprising a first clutch member (80, 82, 84) having a rotational speed determined by the rotational speed of the vehicle engine and a second clutch member (86, 88, 90) having a rotational speed determined by vehicle speed, said shift actuator having a first mode of operation wherein a maximum force is applied for disengaging said first positive clutch;

said control unit including;

logic rules effective, upon sensing a selection of a transmission shift from a currently engaged ratio, for (i) determining a presence of conditions indicative of non-jaw clutch torque lock conditions if a rate of change of an absolute value of a difference between said first input signal and the product of said second input signal multiplied by the currently engaged gear ratio is less than a reference value having a negative value ((d/dt (|IS-(OS*GR)|)<

REF<

0); and

(ii) prohibiting issuing command output signals to said transmission actuator to cause disengagement of said currently engaged transmission ratio in said first mode of operation until it is determined that said conditions indicative of non-jaw clutch torque lock conditions are present.

8. A control system (104 for at least partially automatic implementation of selected shifts of a mechanical change gear transmission system comprising a fuel throttle controlled engine (E), a multispeed change gear mechanical transmission (10) having an input shaft (16) and an output shaft (90) and having a plurality of selectably engageable gear ratios, a non-positive coupling (C) drivingly interposed between the engine and the transmission, a first sensor (98) for providing a first input signal (IS) indicative of input shaft rotational speed, a second sensor (100) for providing a second input signal (OS) indicative of output shaft rotational speed, third sensor means (70/110) for providing a third signal indicative of currently engaged transmission ratio, a non-manually controllable transmission actuator (112, 70, 96) for controlling shifting of the transmission, and a central processing unit (106) for receiving said first second and third input signals and for processing same in accordance with predetermined logic rules to select and implement upshifts and downshifts from the currently engaged gear ratio and to issue command output signals to implement said upshifts and downshifts by the sequence of disengaging a first positive clutch and then engaging a second positive clutch, both of said positive clutches comprising a first clutch member (80, 82, 84) having a rotational speed determined by the rotational speed of the vehicle engine and a second clutch member (86, 88, 90) having a rotational speed determined by vehicle speed, said shift actuator having a first mode of operation wherein a maximum force is applied for disengaging said first positive clutch;

said control control unit including;

logic rules effective, upon sensing a selection of a transmission shift from a currently engaged ratio, for (i) determining a presence of conditions indicative of non-jaw clutch torque lock conditions if the value of a difference between said first input signal and the product of said second input signal multiplied by the currently engaged gear ratio (|IS-(OS*GR)|) changes from a positive to a negative value; and

(ii) prohibiting issuing command output signals to said transmission actuator to cause disengagement of said currently engaged transmission ratio in said first mode of operation until it is determined that said conditions indicative of non-jaw clutch torque lock conditions are present.