Modulation control system and method for a hybrid transmission

• US 9,182,034 B2
• Filed: 03/19/2013
• Issued: 11/10/2015
• Est. Priority Date: 02/17/2011
• Status: Active Grant

• Current Assignee: Allison Transmission Incorporated (Allison Transmission Holdings Incorporated)
• Original Assignee: Allison Transmission Incorporated (Allison Transmission Holdings Incorporated)
• Inventors: Long, Charles F., Taylor, Charles T.
• Primary Examiner(s): Lewis, Tisha
• Application Number:
  US13/846,971
• Publication Number:
  US 20130213501A1
• Time in Patent Office: 966 Days
• Field of Search: 477/15
• US Class Current: 1/1
• CPC Class Codes: B60K 6/12 by means of a chargeable fluidic accumulator
• CPC Class Codes: B60K 6/20 the prime-movers consisting of electric motors and internal combustion engines, e.g. HEVs
• CPC Class Codes: B60K 6/36 characterised by the transmission gearings
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60Y 2200/92 Hybrid vehicles
• CPC Class Codes: F16D 25/14 Fluid pressure control
• CPC Class Codes: F16H 2061/0037 characterised by controlled fluid supply to lubrication circuits of the gearing
• CPC Class Codes: F16H 61/0021 Generation or control of line pressure
• CPC Class Codes: F16H 61/0025 Supply of control fluid; Pumps therefore
• CPC Class Codes: F16H 61/0031 using auxiliary pumps, e.g. pump driven by a different power source than the engine
• 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: F16K 31/0644 One-way valve
• CPC Class Codes: G05D 7/0652 the plurality of throttling means being arranged in parallel
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/902 Prime movers comprising electrical and internal combustion motors
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/915 Specific drive or transmission adapted for hev
• CPC Class Codes: Y10T 137/8593 Systems
• CPC Class Codes: Y10T 137/85986 Pumped fluid control
• CPC Class Codes: Y10T 137/86131 Plural

Abstract

A hydraulic system includes a main modulation control scheme which relies in part on the use of a VBS solenoid and the multiplexing of that solenoid. The hydraulic system is associated with a hybrid module and by controlling the main pressure at a reduced level, the fuel economy and reliability of that hybrid module are improved. The system pressure is controlled by the multiplexed VBS solenoid in order to maintain adequate clutch pressure based on torque requirements. The overall system cost is reduced by the multiplexing of valves and solenoids.

Claims

1. A hydraulic system for a hybrid electrical vehicle comprising:

a sump containing hydraulic fluid;

a main regulator valve constructed and arranged in flow communication with said sump;

a main regulator by-pass valve constructed and arranged in flow communication with said sump;

first and second control solenoids wherein said first control solenoid is a variable bleed solenoid; and

a control module for managing fluid flow of said hydraulic system, wherein said control module is constructed and arranged for multiplexing of said variable bleed solenoid, wherein said multiplexing is applied for said variable bleed solenoid to either hold the main regulator by-pass valve at an applied position or make the variable bleed solenoid available for main boost.

2. The hydraulic system of claim 1 wherein the hybrid electric vehicle has three operational modes associated with the hydraulic system, including an eMode, a transition mode and a cruise mode.

3. The hydraulic system of claim 1 which further includes a mechanical pump constructed and arranged in flow communication with said sump and in flow communication with said main regulator valve for delivering hydraulic fluid from said sump to said main regulator valve.

4. The hydraulic system of claim 3 which further includes an electric pump constructed and arranged in flow communication with said sump and in flow communication with said main regulator by-pass valve for delivering hydraulic fluid from said sump to said main regulator by-pass valve.

5. The hydraulic system of claim 4 wherein said control module is constructed and arranged for managing the operational status of said mechanical pump and of said electric pump based on an operational mode of the hybrid electric vehicle.

6. The hydraulic system of claim 1 wherein said first control solenoid is constructed and arranged in flow communication with said main regulator by-pass valve.

7. The hydraulic system of claim 1 which further includes a clutch trim valve.

8. The hydraulic system of claim 7 wherein said second control solenoid is constructed and arranged in fluid communication with said clutch trim valve.

9. The hydraulic system of claim 1 which further includes a lube bleed conduit in flow communication with a control main valve.

10. The hydraulic system of claim 1 wherein said control module is a hybrid control module with two drivers.

11. The hydraulic system of claim 10 wherein one of said two drivers corresponds to said variable bleed solenoid and the other of said two drivers corresponds to said second control solenoid.

12. The hydraulic system of claim 1 wherein said control module is constructed and arranged to adjust a pressure level of said hydraulic system based on a gearbox torque value.

13. A hydraulic system for a hybrid electrical vehicle comprising:

a sump containing hydraulic fluid;

a main regulator valve constructed and arranged in flow communication with said sump;

a main regulator by-pass valve constructed and arranged in flow communication with said sump;

a hybrid control module; and

a control solenoid constructed and arranged in flow communication with said main regulator by-pass valve wherein said hybrid control module is constructed and arranged for the multiplexing of said control solenoid, wherein said multiplexing is applied for said control solenoid to either hold the main regulator by-pass valve at an applied position or make the control solenoid available for main boost.

14. The hydraulic system of claim 13 wherein said control solenoid is a variable bleed solenoid.

15. The hydraulic system of claim 14 wherein the hybrid electric vehicle has three operational modes associated with the hydraulic system, including an eMode, a transition mode and a cruise mode.

16. The hydraulic system of claim 15 wherein said hybrid control module is constructed and arranged with two drivers.

17. The hydraulic system of claim 16 wherein one of said two drivers corresponds to said variable bleed solenoid and the other of said two drivers corresponds to a second control solenoid.

18. The hydraulic system of claim 17 wherein said hybrid control module is constructed and arranged to adjust a pressure level of said hydraulic system based on a gearbox torque value.

19. A hydraulic system for a hybrid electrical vehicle comprising:

a sump containing hydraulic fluid;

a main regulator valve constructed and arranged in flow communication with said sump;

a main regulator by-pass valve constructed and arranged in flow communication with said sump;

first and second control solenoids wherein said first control solenoid is a variable bleed solenoid;

a mechanical pump in flow communication with said sump;

an electric pump in flow communication with said sump; and

a control module for managing the operational status of each pump, wherein said control module is constructed and arranged for the multiplexing of said variable bleed solenoid, wherein said multiplexing is applied for said variable bleed solenoid to either hold the main regulator by-pass valve at an applied position or make the variable bleed solenoid available for main boost.

20. The hydraulic system of claim 19 wherein the hybrid electric vehicle has three operational modes associated with the hydraulic system, including an eMode, a transition mode and a cruise mode.

21. The hydraulic system of claim 19 wherein said first control solenoid is constructed and arranged in flow communication with said main regulator by-pass valve.

22. The hydraulic system of claim 19 which further includes a clutch trim valve.

23. The hydraulic system of claim 22 wherein said second control solenoid is constructed and arranged in fluid communication with said clutch trim valve.

24. A hydraulic system for a hybrid electrical vehicle comprising:

a sump containing hydraulic fluid;

a main regulator valve constructed and arranged in flow communication with said sump;

a main regulator by-pass valve constructed and arranged in flow communication with said sump;

first and second control solenoids wherein said first control solenoid is a variable bleed solenoid;

a clutch trim valve; and

wherein said second control solenoid is constructed and arranged in fluid communication with said clutch trim valve.

25. The hydraulic system of claim 24 wherein the hybrid electric vehicle has three operational modes associated with the hydraulic system, including an eMode, a transition mode and a cruise mode.

26. The hydraulic system of claim 24 wherein said control module is constructed and arranged for managing the operational status of said mechanical pump and of said electric pump based on an operational mode of the hybrid electric vehicle.

27. The hydraulic system of claim 24 wherein said first control solenoid is constructed and arranged in flow communication with said main regulator by-pass valve.

28. A hydraulic system for a hybrid electrical vehicle comprising:

a sump containing hydraulic fluid;

a main regulator valve constructed and arranged in flow communication with said sump;

a main regulator by-pass valve constructed and arranged in flow communication with said sump;

first and second control solenoids wherein said first control solenoid is a variable bleed solenoid;

a clutch trim valve, wherein said second control solenoid is constructed and arranged in fluid communication with said clutch trim valve; and

a control module for managing fluid flow of said hydraulic system, wherein said control module is constructed and arranged for multiplexing of said variable bleed solenoid.

29. A hydraulic system for a hybrid electrical vehicle comprising:

a sump containing hydraulic fluid;

a main regulator valve constructed and arranged in flow communication with said sump;

a main regulator by-pass valve constructed and arranged in flow communication with said sump;

first and second control solenoids wherein said first control solenoid is a variable bleed solenoid;

a clutch trim valve, wherein said second control solenoid is constructed and arranged in communication with said clutch trim valve;

a mechanical pump in flow communication with said sump;

an electric pump in flow communication with said sump; and

a control module for managing the operational status of each pump, wherein said control module is constructed and arranged for the multiplexing of said variable bleed solenoid.