Controller for variable transmission

• US 10,100,927 B2
• Filed: 10/31/2014
• Issued: 10/16/2018
• Est. Priority Date: 11/16/2007
• Status: Active Grant

• Current Assignee: Enviolo BV
• Original Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Inventors: Quinn, Jr., Stanley B., Miller, Alan L., Anderson, Scott R.
• Primary Examiner(s): Smith, Jelani A
• Assistant Examiner(s): Williams, Kelly D
• Application Number:
  US14/529,773
• Publication Number:
  US 20150051801A1
• Time in Patent Office: 1,446 Days
• 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 in a drivetrain having a ball planetary type variator, the drivetrain having at least two forward modes, a reverse mode, and one of a neutral mode and a park mode, the method comprising:

storing, in a shift schedule module, a shift schedule map;

receiving, by a shift point module, a plurality of input signals, wherein the plurality of input signals includes an engine parameter and a transmission ratio;

determining an active control range from a plurality of control ranges based at least in part on the plurality of input signals and the shift schedule map, wherein each control range corresponds to a range of transmission ratios;

configuring a range box into one of the at least two forward modes, the reverse mode, and the neutral mode or the park mode;

determining an active variator mode from a plurality of variator modes based on the plurality of input signals and the active control range, wherein at least one variator mode includes a 1;

1 ratio; 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 controlling actuation of a clutch to activate the configuration of the range box.

3. The method of claim 1, further comprising controlling the range box to provide a gear ratio based on the configuration of the range box.

4. 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.

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

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

7. 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.

8. The method of claim 7, wherein the plurality of input signals comprises:

a throttle position sensor value; and

a vehicle speed value.

9. 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.

10. 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.

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

12. The method of claim 11, 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.

13. A controller system for controlling a variable ration transmission in a drivetrain having a ball planetary type variator, the drivetrain having at least two forward modes, a reverse mode, and one of a neutral mode and a park mode, the controller system comprising:

a controller including a plurality of modules comprising;

a shift schedule module configured to store a shift schedule map on a computer readable medium;

a shift point module communicatively coupled to the shift schedule module and the computer readable medium, the shift point module configured to;

receive a plurality of electronic input signals from one or more sensors, wherein the plurality of electronic input signals includes an engine parameter and a transmission ratio,

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, and wherein each control range corresponds to a range of transmission ratios, and

configure a range box into one of the at least two forward modes, the reverse mode, and the neutral mode or the park mode;

a variator mode module configured to receive the plurality of electronic input signals and the active control range and determine a variator mode based on the plurality of electronic input signals and the active control range, wherein at least one variator mode includes a 1;

1 ratio; and

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

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

14. The controller system of claim 13, wherein the controller further comprises a shift logic module communicatively 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 the range box coupled to the variator.

15. The controller system of claim 14, wherein the controller further comprises a shift quality control module coupled to the shift logic module and configured to control an electronic solenoid to control engagement of the at least one clutch, wherein the shift quality control module is configured to determine an application rate and a corresponding solenoid current.

16. The controller system of claim 13, wherein the controller further comprises an engine speed setpoint module communicatively 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.