CONSTANT SPEED DRIVE AND GENERATOR

• US 3,576,143 A
• Filed: 09/05/1969
• Issued: 04/27/1971
• Est. Priority Date: 09/05/1969
• Status: Expired due to Term

• Current Assignee: Stephen S. Baits
• Original Assignee: Stephen S. Baits
• Inventors: Baits, Stephen S.
• Application Number:
  US04/855,495
• Time in Patent Office: 599 Days
• US Class Current: 475/77
• CPC Class Codes: F16H 47/04 the mechanical gearing being of the type with members having orbital motion
• CPC Class Codes: H02K 7/1807 Rotary generators H02K7/006 takes precedence

Abstract

An integrated constant speed drive and generator for providing electrical power to aircraft including a constant speed drive housing open at one end and having drive components therein including a differential and an hydraulic drive, and a generator housing also open at one end and having a generator mounted therein with the housings interconnected so that they open to one another and define a common sump for generator cooling fluid as well as drive control and lubrication fluid, there being provided a single charge pump in the generator drive housing portion that provides hydraulic fluid for controlling the drive, lubricating the drive components, and cooling the generator rotor and stator by direct contact of the cooling fluid therewith.

Claims

1. A drive and generator combination, comprising:

a generator having a stationary stator and a rotor adapted to be driven at a substantially constant speed, a constant speed drive for driving the rotor including an input shaft member adapted to be driven by a prime mover, an output shaft member connected to drive the rotor, differential gearing between the input and output shaft members including a control gear for varying the speed of the output shaft member with respect to the input shaft member, a first hydraulic unit drivingly connected to one of said members, a second hydraulic unit drivingly connected to said control gear, conduit means hydraulically interconnecting said first and second hydraulic units, control means for varying the displacement of one of said hydraulic units to maintain a substantially constant rotor speed, housing means for said generator, said differential and said hydraulic units, means for delivering control fluid to said control means, means for delivering hydraulic fluid to said generator, and a common sump in said housing means for both of said fluids.

2. A drive and generator combination as defined in claim 1, including a single scavenge pump in said housing means for scavenging fluid from said common sump.

3. A drive and generator combination as defined in claim 1, including a single charge pump in said housing means for supplying said fluid to said control means and to said generator.

4. A drive and generator combination as defined in claim 3, including means for supplying lubrication fluid to said differential, said charge pump being connected to supply said lubrication fluid to the differential.

5. A drive and generator combination as defined in claim 1, wherein said means for supplying fluid to said generator includes means for supplying cooling hydraulic fluid in direct contact with said stator.

6. A drive and generator combination as defined in claim 1, wherein said means for supplying fluid to said generator includes means for supplying cooling hydraulic fluid in direct contact with said rotor.

7. A drive and generator combination as defined in claim 1, wherein said housing means includes a reservoir hydraulically separate from said sump and adapted to contain fluid to be supplied to both the drive and the generator, a single charge pump for receiving fluid from said reservoir and for conveying the fluid to the control means and said generator.

8. A drive and generator combination as defined in claim 7, including a scavenge pump in said housing means for delivering fluid from said common sump to said reservoir.

9. A drive and generator combination, comprising:

a generator having a stationary stator and a rotor adapted to be driven at a substantially constant speed, a constant speed drive for driving the rotor including an input shaft member adapted to be driven by a prime mover, an output shaft member connected to drive the rotor, differential gearing between the input and output shaft members including a control gear for varying the speed of the output shaft member with respect to the input shaft member, a first hydraulic unit drivingly connected to one of said members, a second hydraulic unit drivingly connected to said control gear, conduit means hydraulically interconnecting said first and second hydraulic units, control means for varying the displacement of one of said hydraulic units to maintain a substantially constant rotor speed, said differential including a gear carrier in line with said input shaft member and with said output member, said control gear being in line with said input shaft member and said output shaft member, said output shaft member being directly connected to said rotor thereby eliminating the necessity for drive gearing between the differential output member and the rotor.

10. A drive and generator combination as defined in claim 9, including a third hydraulic unit drivingly connected to said one shaft member, a fourth hydraulic unit drivingly connected to said control gear, second conduit means interconnecting the third and fourth hydraulic units, second control means for varying the displacement of at least one of said third and fourth hydraulic units, said first and second hydraulic units being in back-to-back relation and offset with respect to the axis of said input and output shaft members, said third and fourth hydraulic units being in back-to-back relation and offset with respect to said input and output shaft members.

11. In an integrated constant speed drive and generator, the combination, comprising:

a generally cylindrical generator housing open at one end, a generally cylindrical drive housing open at one end, means for attaching the two housings in end to end relationship with the apertured and open ends adjacent each other, a generator in the generator housing including a stator stationarily mounted in the housing, and a rotor mounted for rotation within the stator, an input shaft mounted in one of the housings, a mechanical differential including input gearing adapted to be driven by the input shaft, output gearing adapted to drive the generator rotor, and control gearing adapted to vary the speed ratio of the output gearing to the input gearing, a hydrostatic transmission in the constant speed drive housing including a pair of rotary axial piston hydraulic units connected in closed hydraulic circuit, means for varying the displacement of at least one of the hydraulic units, means connecting one of the hydraulic units to be driven by the input shaft, and means connecting the other hydraulic unit to drive the control gearing in the differential, means responsive to the speed of the output gearing for controlling the displacement-varying means so that the output gearing and generator are driven at a constant speed regardless of variation in speed of the input shaft, a reservoir in the constant speed drive housing, a charge pump communicating with the reservoir for supplying control fluid to the constant speed control, conduit means communicating with the charge pump for lubricating the differential gearing, conduit means communicating with the charge pump for cooling the generator, means for collecting leakage, lubricating and cooling fluid, and a scavenge pump in communication with the collecting means for delivering fluid from the collecting means to the reservoir.

12. A drive and generaTor combination, comprising:

a generator having a stationary stator and a rotor adapted to be driven at a substantially constant speed, a constant speed drive for driving the rotor including an input shaft member adapted to be driven by a prime mover, an output shaft member connected to drive the rotor, differential gearing between the input and output shaft members including a control gear for varying the speed of the output shaft member with respect to the input shaft member, a first hydraulic unit drivingly connected to one of said members, a second hydraulic unit drivingly connected to said control gear, conduit means hydraulically interconnecting said first and second hydraulic units, control means for varying the displacement of one of said hydraulic units to maintain a substantially constant rotor speed, a charge pump in said housing means for supplying control fluid to said control means, passage means in said housing means for supplying cooling fluid to said generator, said passage means being connected to receive cooling fluid from said charge pump, said passage means including integrally molded axial passage means in said housing means directly communicating with the generator stator.

13. A drive and generator combination, comprising:

a generator having a stationary stator and a rotor adapted to be driven at a substantially constant speed, a constant speed drive for driving the rotor including an input shaft member adapted to be driven by a prime mover, an output shaft member connected to drive the rotor, differential gearing between the input and output shaft members including a control gear for varying the speed of the output shaft member with respect to the input shaft member, a first hydraulic unit drivingly connected to one of said members, a second hydraulic unit drivingly connected to said control gear, conduit means hydraulically interconnecting said first and second hydraulic units, control means for varying the displacement of one of said hydraulic units to maintain a substantially constant rotor speed, a charge pump in said housing means for supplying control fluid to said control means, passage means in said housing means for supplying cooling fluid to said generator, said passage means being connected to receive cooling fluid from said charge pump, and shaft means supporting said rotor, said passage means including first passage means extending radially in said rotor shaft means and adapted to directly apply cooling fluid to said rotor.

14. A drive and generator combination, comprising:

a generator having a stationary stator and a rotor adapted to be driven at a substantially constant speed, a constant speed drive for driving the rotor including an input shaft member adapted to be driven by a prime mover, an output shaft member connected to drive the rotor, differential gearing between the input and output shaft members including a control gear for varying the speed of the output shaft member with respect to the input shaft member, a first hydraulic unit drivingly connected to one of said members, a second hydraulic unit drivingly connected to said control gear, conduit means hydraulically interconnecting said first and second hydraulic units, control means for varying the displacement of one of said hydraulic units to maintain a substantially constant rotor speed, a charge pump in said housing means for supplying control fluid to said control means, passage means in said housing means for supplying cooling fluid to said generator, said passage means being connected to receive cooling fluid from said charge pump, and means freely communicating the generator and the differential and hydraulic units whereby the environment for the generator is the same as the environment for the differential and hydraulic units.

15. A drive and generator combination, comprising:

a generator having a stationary stator and a rotor adapted to be driven at a substantially constant speed, a constant speed drive for driving the rotor including an input shaft member aDapted to be driven by a prime mover, an output shaft member connected to drive the rotor, differential gearing between the input and output shaft members including a control gear for varying the speed of the output shaft member with respect to the input shaft member, a first hydraulic unit drivingly connected to one of said members, a second hydraulic unit drivingly connected to said control gear, conduit means hydraulically interconnecting said first and second hydraulic units, control means for varying the displacement of one of said hydraulic units to maintain a substantially constant rotor speed, housing means for said generator, said differential and said hydraulic units, a rotor shaft carrying said generator rotor, said differential including a first gear and a second gear in addition to said control gear, at least two of said gears being located within said rotor shaft.

16. A drive and generator combination as defined in claim 15, wherein said rotor shaft, said differential and said input shaft are aligned on a common axis.

17. A drive and generator combination as defined in claim 16, wherein said differential includes a first sleeve-shaped ring gear, a second sleeve-shaped ring gear coaxial with said first ring gear, a carrier extending within said ring gears and having two intermeshing pinions thereon, one of said sleeve ring gears being within said rotor shaft, one of said ring gears being stepped and having an external gear thereon, governor means for said control means, and gear means drivingly interconnecting said external gear and said governor means.

18. A drive and generator combination as defined in claim 15, said housing means having bearing means supporting one end of said rotor shaft, second bearing means in said housing means supporting the other end of said rotor shaft, and third bearing means within said rotor shaft for supporting one of said differential gears.

19. A drive and generator combination, comprising:

a generator having a stationary stator and a rotor adapted to be driven at a substantially constant speed, a constant speed drive for driving the rotor including an input shaft member adapted to be driven by a prime mover, an output shaft member connected to drive the rotor, differential gearing between the input and output shaft members including a control gear for varying the speed of the output shaft member with respect to the input shaft member, a first hydraulic unit drivingly connected to one of said members, a second hydraulic unit drivingly connected to said control gear, conduit means hydraulically interconnecting said first and second hydraulic units, control means for varying the displacement of one of said hydraulic units to maintain a substantially constant rotor speed, a charge pump for supplying cooling fluid to said generator rotor, first passage means in said generator rotor for carrying cooling fluid in a direction toward the differential and second passage means for carrying cooling fluid from said charge pump to said first passage means.

20. A drive and generator combination as defined in claim 19, including third passage means in said differential for lubricating the same, said first passage means being connected to convey lubricating fluid to said third passage means.