Converterless multiple-ratio automatic transmission

• US 6,217,479 B1
• Filed: 07/15/1999
• Issued: 04/17/2001
• Est. Priority Date: 07/15/1999
• Status: Expired due to Fees

• Current Assignee: Steve Regan
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Ortmann, Walter Joseph, Kraska, Marvin Paul, Brown, Larry Thomas
• Primary Examiner(s): Estremsky, Sherry
• Assistant Examiner(s): Waddell, Tisha D.
• Application Number:
  US09/353,289
• Time in Patent Office: 642 Days
• Field of Search: 477/70, 477/77, 477/86, 477/87, 477/166, 477/167, 477/169, 475/207, 475/208, 475/214, 475/215
• US Class Current: 477/86
• CPC Class Codes: F16H 2059/366 Engine or motor speed
• CPC Class Codes: F16H 2061/1204 for malfunction caused by simultaneous engagement of different ratios resulting in transmission lock state or tie-up condition
• CPC Class Codes: F16H 2061/1232 Bringing the control into a predefined state, e.g. giving priority to particular actuators or gear ratios
• CPC Class Codes: F16H 2061/1292 the failing part is the power supply, e.g. the electric power supply
• CPC Class Codes: F16H 2200/0043 the gear ratios comprising four forward speeds
• CPC Class Codes: F16H 2312/02 Driving off
• CPC Class Codes: F16H 2312/20 Start-up or shut-down
• CPC Class Codes: F16H 3/66 composed of a number of gear trains without drive passing from one train to another
• CPC Class Codes: F16H 57/0006 Vibration-damping or noise reducing means specially adapted for gearings devices for varying tension of belts, ropes or chains with damping means F16H7/0829; toothed members with construction providing vibration damping F16H55/14; reducing vibrations or noise of the gearbox casing F16H57/028; suppression of vibrations or noise of gear selectors F16H59/0208; control of hydrostatic fluid gearing preventing or reducing vibrations or noise F16H61/4183
• CPC Class Codes: F16H 61/0206 Layout of electro-hydraulic control circuits, e.g. arrangement of valves for control of actuators selecting and moving final output members, e.g. shift forks F16H61/2807
• CPC Class Codes: F16H 61/0246 characterised by initiating reverse gearshift
• CPC Class Codes: F16H 61/0283 Governor valves
• 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 61/686 with orbital gears

Abstract

A multiple-ratio transmission with planetary gearing and a friction clutch and brake for controlling relative motion of the gearing to establish multiple driving ratios between an internal combustion engine and vehicle traction wheels, the clutch and brake include a forward drive clutch and a reverse drive clutch for establishing torque flow paths through the gearing. The forward drive clutch establishes a torque flow path through the gearing from the engine through a torque output element of the transmission during vehicle startup in forward drive range, and the reverse clutch establishes a corresponding torque flow path during startup in reverse. A mechanical connection between the torque input shaft of the gearing and the crankshaft is characterized by minimal rotating mass, thereby reducing the inertia of rotating mass of the elements of the transmission.

Claims

1. A converterless, multiple-ratio, automatic transmission for a vehicle driveline having an internal combustion engine, the transmission including a driven shaft in a torque flow path to vehicle traction vehicles;

planetary gearing of the transmission defining multiple forward drive torque flow paths between the engine and the driven shaft;

the engine having a crankshaft directly connected drivably to a torque input element of the gearing whereby the crankshaft and the torque input element are continuously coupled during torque delivery through the torque flow paths for rotation in unison;

pressure-operated friction clutch means in the transmission for establishing and disestablishing the torque flow paths including a forward drive clutch that is engaged for forward drive operation; and

automatic clutch control means for disengaging and engaging the forward drive clutch to respectively disconnect and connect the engine from and to the gearing, thereby effecting control of the driveline during vehicle startup in forward drive.

3. The automatic transmission set forth in claim 1 wherein the clutch control means comprises a line pressure pump connected to the torque input element of the gearing;

a control valve circuit means including an electronic processor and a manually operable range selector valve for distributing pressure generated by the line pressure pump to the forward drive clutch in a closed-loop fashion with actual engine torque as a feedback variable whereby forward clutch pressure effects a controlled and smooth engagement during vehicle startup;

the processor including means for continuously detecting actual engine torque during a vehicle launch in forward drive and comparing it to a target engine torque determined by a vehicle operator to detect an error and establishing a forward drive clutch pressure that is functionally related to the magnitude of the error.

6. The converterless transmission set forth in claim 3 wherein the control valve circuit includes solenoid-operated valve means communicating with the line pressure pump for establishing a controlled pressure for distribution to the clutch means in the transmission;

and

an auxiliary pressure source including a pitot tube pressure element and a rotary fluid reservoir driven by the engine containing fluid that is engaged by the pitot tube pressure element; and

means for establishing controlled communication between the auxiliary pressure source and the clutch means in the transmission when the solenoid-operated valve means is disabled.

2. A converterless, multiple-ratio, automatic transmission for a vehicle driveline having an internal combustion engine, the transmission including a driven shaft in a torque flow path to vehicle traction wheels;

planetary gearing of the transmission defining a reverse drive torque flow path between the engine and the driven shaft;

the engine having a crankshaft directly connected drivably to a torque input element of the gearing whereby the crankshaft and the torque input element are continuously coupled during torque delivery through the reverse drive torque flow path for rotation in unison;

pressure-operated friction clutch means in the transmission for establishing and disestablishing a reverse drive torque flow path including a reverse drive clutch that is engaged for reverse drive operation; and

automatic clutch control means for disengaging and engaging the reverse drive clutch to respectively disconnect and connect the engine from and to the gearing, thereby effecting control of the driveline during vehicle startup in reverse drive.

4. The automatic transmission set forth in claim 2 wherein the clutch control means comprises a line pressure pump connected to the torque input element of the gearing;

a control valve circuit means including an electronic processor and a manually operable range selector valve for distributing pressure generated by the line pressure pump to the reverse drive clutch in a closed-loop fashion with actual engine torque as a feedback variable whereby reverse clutch pressure effects a controlled and smooth engagement during vehicle startup;

the processor including means for continuously detecting actual engine torque during a vehicle launch in reverse drive and comparing it to a target engine torque determined by a vehicle operator to detect an engine torque error and establishing a reverse drive clutch pressure that is functionally related to the magnitude of the torque error.

5. A converterless transmission as set forth in claim 2 wherein the clutch control means comprises a line pressure pump connected to the torque input element of the gearing;

a control valve circuit means including an electronic processor and a manually operable range selector valve for distributing pressure generated by the line pressure pump to the forward drive clutch in a closed-loop fashion with actual engine speed as a feedback variable to establish modulated pressure engagement of the forward drive clutch thereby effecting torsional vibration isolation during operation of the vehicle following launch;

the processor including means for continuously detecting actual engine speed and comparing to a speed commanded by a vehicle operator to detect an engine speed error and establishing a controlled pressure in a pressure-operated clutch means in the transmission that is functionally related to the speed error.

7. The converterless transmission set forth in claim 4 wherein the control valve circuit includes solenoid-operated valve means communicating with the line pressure pump for establishing a controlled pressure for distribution to the clutch means in the transmission;

and

an auxiliary pressure source including a pitot tube pressure element and a rotary fluid reservoir driven by the engine containing fluid that is engaged by the pitot tube pressure element; and

means for establishing controlled communication between the auxiliary pressure source and the clutch means in the transmission when the solenoid-operated valve means is disabled.