Hybrid fan drive with CVT and electric motor

Patent metadata

Field	Value
Publication number	US-9181850-B2
Application number	US-201013500946-A
Country	US
Kind code	B2
Filing date	Oct 15, 2010
Priority date	Oct 17, 2009
Publication date	Nov 10, 2015
Grant date	Nov 10, 2015

Abstract

A hybrid accessory drive system having two operational modes, a mechanical mode and an electric mode. The accessory is typically a cooling fan. A continuously variable mechanical belt drive mechanism drives the accessory as one mode of operation. An electric motor along with a planetary roller screw mechanism which converts rotary motion to axial motion is used to change the sheave position and thus the drive ratio. Upon disengagement of the mechanical drive mode, the electric motor can be used to drive the accessory in a second mode.

First claim

What is claimed is:

1. A hybrid system for driving a cooling fan comprising:
a driving member having a pair of sheave members and a first rotating shaft member, said shaft member connected to a source of rotary motion;
a driven member having a pair of sheave members and a second rotating shaft member, a first sheave of said pair of sheave members of said driven member being securely attached to said second rotating shaft member, and second sheave of said pair of sheave members of said driven member being slidingly connected to said second rotating shaft member;
a belt member connected between said driving member and said driven member;
a fan member attached to said first sheave of said pair of sheave members of said driven member on said driven member;
a sheave actuation system for axially sliding said second sheave of said pair of sheave members of said driven member on said driven member along said second rotating shaft member;
said sheave actuation system comprising an electric motor and a planetary roller screw mechanism; and
a clutch mechanism for allowing said electric motor to independently drive said driven member.

2. A hybrid system as described in claim 1 wherein said driving member has at least one flyweight to provide tensioning to the belt drive system.

3. The hybrid system as described in claim 1 further comprising a belt disengagement mechanism on said driving member.

4. The hybrid system as described in claim 3 wherein said belt disengagement mechanism comprises a pair of free spinning surface members.

5. The hybrid system as described in claim 4 further comprising bearing members for allowing rotation of said pair of free spinning surface members independent of said driving member.

6. The hybrid system as described in claim 1 wherein said belt member is a V-shaped belt member.

7. The hybrid system as described in claim 1 further comprising a Hall Effect Device for measuring the speed of rotation of said second rotating shaft member.

8. The hybrid system as described in claim 7 wherein said Hall Effect Device also measures the speed of said fan member.

9. The hybrid system as described in claim 1 wherein said electric motor is a brushless DC motor.

10. The hybrid system as described in claim 1 further comprising a sheave drive member attached to said second of said pair of sheave members on said driven member, and said clutch mechanism selective connecting said sheave drive member directly to said electric motor.

11. The hybrid system as described in claim 10 wherein said clutch mechanism is a pawl-type clutch mechanism.

12. The hybrid system as described in claim 1 wherein said clutch mechanism is a pawl-type clutch mechanism.

13. The hybrid system as described in claim 1 wherein said electric motor comprises a stator member and a rotor member, and further comprising a rotor housing member attached to said rotor member and rotatable therewith.

14. The hybrid system as described in claim 13 further comprising a sheave drive member attached to said second of said pair of sheave members on said driven member, and said clutch mechanism is a pawl-type clutch mechanism with a plurality of pawl members, said sheave drive member having a plurality of notches for mating with said pawl members.

15. The hybrid system as described in claim 1 wherein said planetary roller screw mechanism comprises a roller screw housing member, a threaded sleeve member and a plurality of roller members.

16. The hybrid system as described in claim 15 wherein said threaded sleeve member has spiral-type screw threads and said roller members have circular-type ridge members.

17. The hybrid system as described in claim 1 further comprising a thrust bearing positioned between said planetary roller screw mechanism and said second sheave of said pair of sheave members of said driven member.

18. The hybrid system as described in claim 1 wherein said electric motor has a stator member, a rotor member, and a rotor housing member, and further comprising a second clutch mechanism for selectively engaging said rotor housing member to said planetary roller screw mechanism.

19. A hybrid system for driving an accessory member for a vehicle engine, said system comprising:
a driving member having a pair of sheave members and a first rotating shaft member, said shaft member connected to a source of rotary motion;
a driven member having a pair of sheave members and a second rotating shaft member, a first sheave of said pair of sheave members of said driven member being securely attached to said second rotating shaft member, and a second sheave of said pair of sheave members of said driven member being slidingly connected to said second rotating shaft member;
a belt member connected between said driving member and said driven member;
an accessory member attached to said first sheave of said pair of sheave members of said driven member on said driven member;
a sheave actuation system for axially sliding said second sheave of said pair of sheave members of said driven member on said driven member along said second rotating shaft member;
said sheave actuation system comprising an electric motor and a planetary roller screw mechanism; and
a clutch mechanism for allowing said electric motor to independently drive said driven member.

20. The hybrid system as described in claim 19 wherein said accessory member comprises a fan member.

Assignees

• Roby Joshua L
• Borgwarner Inc

Inventors

• Roby Joshua L

Classifications

• F01P7/046 Primary

  using mechanical drives · CPC title

• F01P7/048

  using electrical drives · CPC title