CONTROLLER FOR VARIABLE TRANSMISSION

• US 20150051801A1
• Filed: 10/31/2014
• Published: 02/19/2015
• Est. Priority Date: 11/16/2007
• Status: Active Grant

• Current Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Original Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Inventors: Quinn, Stanley B. Jr., Miller, Alan L., Anderson, Scott R.
• Granted Patent: US 10,100,927 B2
• Time in Patent Office: Days
• US Class Current: 701/55
• CPC Class Codes: F16H 15/28 with external friction surface
• CPC Class Codes: F16H 2037/088 Power split variators with summing differentials, with the input of the CVT connected or connectable to the input shaft
• CPC Class Codes: F16H 2037/0886 with switching means, e.g. to change ranges
• CPC Class Codes: F16H 2061/1208 with diagnostic check cycles; Monitoring of failures
• CPC Class Codes: F16H 2061/6601 with arrangements for dividing torque and shifting between different ranges
• CPC Class Codes: F16H 2200/0039 the gear ratios comprising three forward speeds
• CPC Class Codes: F16H 2200/2005 with one sets of orbital gears
• CPC Class Codes: F16H 2200/2023 using a Ravigneaux set with 4 connections
• CPC Class Codes: F16H 2200/2041 with four engaging means
• CPC Class Codes: F16H 3/663 with conveying rotary motion between axially spaced orbital gears, e.g. RAVIGNEAUX
• CPC Class Codes: F16H 37/086 CVT using two coaxial friction members cooperating with at least one intermediate friction member
• 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 61/6648 controlling of shifting being influenced by a signal derived from the engine and the main coupling
• CPC Class Codes: F16H 61/6649 characterised by the means for controlling the torque transmitting capability of the gearing
• CPC Class Codes: F16H 61/70 specially adapted for change-speed gearing in group arrangement, i.e. with separate change-speed gear trains arranged in series, e.g. range or overdrive-type gearing arrangements

Abstract

An electronic controller for a variable ratio transmission and an electronically controllable variable ratio transmission including a variator or other CVT are described herein. The electronic controller can be configured to receive input signals indicative of parameters associated with an engine coupled to the transmission. The electronic controller can also receive one or more control inputs. The electronic controller can determine an active range and an active variator mode based on the input signals and control inputs. The electronic controller can control a final drive ratio of the variable ratio transmission by controlling one or more electronic solenoids that control the ratios of one or more portions of the variable ratio transmission.

Claims

1. A method of controlling a variable ratio transmission, the method comprising:

receiving a plurality of input signals;

determining an active control range from a plurality of control ranges based at least in part on the plurality of input signals;

determining an active variator mode from a plurality of variator modes based on the plurality of input signals and the active control range; and

controlling an operation of the variator based on the input signals and the active variator mode.

2. The method of claim 1, further comprising determining a configuration of a range box coupled to the variator based at least in part on the plurality of input signals.

3. The method of claim 2, further comprising controlling actuation of a clutch to activate the configuration of the range box.

4. The method of claim 2, further comprising controlling the range box to provide a gear ratio based on the configuration.

5. The method of claim 1, further comprising:

determining a configuration of a torque converter clutch corresponding to a torque converter that couples power from a prime mover to the variator; and

selectively engaging the torque converter clutch based on the configuration of the torque converter clutch.

6. The method of claim 1, wherein receiving the input signals comprises receiving at least one sensor value and at least one control state.

7. The method of claim 1, wherein receiving the input signals comprises receiving a throttle position sensor input value and a gear selector value.

8. The method of claim 1, wherein determining the active control range comprises:

retrieving at least a portion of a shift curve; and

determining the active control range based on the portion of the shift curve and the plurality of input signals.

9. The method of claim 8, wherein the plurality of input signals comprise:

a throttle position sensor value; and

a vehicle speed value.

10. The method of claim 1, wherein controlling the operation of the variator comprises modulating a current applied to an electronic solenoid to control a ratio of the variator.

11. The method of claim 1, wherein controlling the operation of the variator comprises controlling the variator to provide a ratio from a range of ratios that spans an underdrive ratio and an overdrive ratio.

12. The method of claim 1, wherein controlling the operation of the variator comprises controlling a longitudinal axis of a rotating planet within the variator.

13. The method of claim 12, wherein controlling the longitudinal axis comprises controlling a position of a shift lever coupled to the rotating planet by modulating a current applied to a control solenoid.

14. A controller system, the system comprising:

a shift schedule module configured to store a shift schedule map;

a shift point module coupled to the shift schedule module, configured to receive a plurality of electronic input signals, and configured to determine an active control range from a plurality of control ranges based at least in part on the plurality of electronic input signals and the shift schedule map;

a variator mode module configured to determine a variator mode based on the plurality of electronic input signals and the active control range; and

a control module configured to control a ratio of a variator based on the variator mode.

15. The controller system of claim 14, further comprising a shift logic module coupled to the shift point module and configured to receive the active control range from the shift point module, wherein the shift point module is configured to determine a state of an upshift flag and a downshift flag based on the plurality of electronic input signals, and wherein the shift logic module is configured to control engagement of at least one clutch controlling a ratio of a rangebox coupled to the variator.

16. The controller system of claim 15, further comprising a shift quality control module coupled to the shift logic module and configured to control an electronic solenoid based on a predetermined shift profile to control engagement of the at least one clutch.

17. The controller system of claim 14, further comprising an engine speed setpoint module coupled to the variator mode module and configured to determine an engine speed setpoint value based on the variator mode, and wherein the control module is configured to receive an engine speed value and is configured to control the ratio of the variator based on the engine speed value and the engine speed setpoint.

18. The controller system of claim 14, wherein each of the shift schedule module, the shift point module, the variator mode module, and the control module are embodied as one or more of an application specific integrated circuit, at least one processor circuit, or software stored on a computer readable media and configured to be executed by a processor.