Continuously variable transmission using planetary gearing with regenerative torque transfer and employing belt slip to measure and control pulley torque

• US 5,011,458 A
• Filed: 09/12/1989
• Issued: 04/30/1991
• Est. Priority Date: 11/09/1988
• Status: Expired due to Fees

• Current Assignee: KUMM Industries Incorporated
• Original Assignee: KUMM Industries Incorporated
• Inventors: Kumm, Emerson L.
• Primary Examiner(s): Herrmann, Allan D.
• Assistant Examiner(s): TA, KHOI QUANG
• Application Number:
  US07/406,975
• Time in Patent Office: 595 Days
• Field of Search: 474/18, 474/28, 474/49, 474/52, 474/56, 474/70, 474/109, 74/866, 475/208-211
• US Class Current: 474/49
• 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 2061/6614 Control of ratio during dual or multiple pass shifting for enlarged ration coverage
• CPC Class Codes: F16H 37/0846 CVT using endless flexible members
• CPC Class Codes: F16H 61/66263 using only hydraulical and mechanical sensing or control means
• CPC Class Codes: F16H 9/10 engaging a pulley provided with radially-actuatable elements carrying the belt
• CPC Class Codes: Y10T 74/19 Gearing

Abstract

A continuously variable, regenerative transmission is disclosed in which a continuously variable transmission assembly is employed in conjunction with a regenerative gear assembly incorporating high and low clutches and situated intermediate a prime mover, such as a vehicle engine, and an output, such as the drive train to vehicle wheels. By monitoring certain system conditions (such as the rate and direction of rotation desired for the output, the rate of rotation of the engine and belt slip) while simultaneously controlling the engine speed, a control subsystem adjusts the effective diameters of input and output pulleys of the continuously variable transmission assembly to obtain a pulley torque versus belt tension that gives a belt slip value which results in rotation of the output in the desired direction at a rate according to a predetermined ratio schedule of the rate of rotation of the engine with respect to the rate of rotation of the output under the measured instantaneous conditions and in view of the output speed desired.

Claims

1. A continuously variable, regenerative transmission mechanically disposed intermediate a prime mover source of variable rotational power and variable unidirectional rotational speed output and a geared output shaft having a variable rotational rate and variable rotational direction, said regenerative transmission comprising:

(A) a continuously variable transmission assembly

(1) a first variable diameter pulley;

(2) a first actuator for establishing the diameter of said first variable diameter pulley;

(3) a second variable diameter pulley;

(4) a second actuator for establishing the diameter of said second variable diameter pulley; and

(5) a belt coupling said first and second variable diameter pulleys;

(B) an input shaft coupled to said first variable diameter pulley and to a prime mover;

(C) a sun gear shaft coupled to said second variable diameter pulley, said sun gear shaft carrying a high gear rotating therewith;

(D) a planetary gear assembly coupled to said sun gear shaft, said planetary gear assembly including;

(1) a sun gear rotating with said sun gear shaft;

(2) a planet carrier rotatably about said sun gear shaft axis;

(3) a plurality of planet gears carried by said planet carrier and meshing with said sun gear;

(4) a ring gear meshing with said planet gears; and

(5) a low gear rotating with said ring gear;

(E) transfer means coupling rotation of said input shaft to said planet carrier;

(F) an output shaft, said output shaft having an output gear rotating therewith;

(G) a high output gear rotatably carried by said output shaft, said high output gear being coupled to said high gear;

(H) a low output gear rotatably carried by said output shaft, said low output gear being coupled to said low gear;

(I) a high clutch adapted to selectively couple said high output gear to said output shaft;

(J) a low clutch adapted to selectively couple said low output gear to said output shaft; and

(K) control means including;

(1) means to sense the rate of rotation of said output gear, on said output shaft;

(2) means to give a desired rotational direction of said output gear, on said output shaft;

(3) means to sense the rotation-al direction of said output gear, on said output shaft;

(4) means to sense the rate of rotation of a prime mover;

(5) means to adjust the rate of rotation of a prime mover;

(6) means to actuate at least one of said high and low clutches; and

(7) means to adjust said first and second actuators to obtain a belt slip that corresponds to a pulley torque versus belt tension which results in rotation of said output gear in the desired direction at a rate according to a predetermined ratio of the rate of rotation of the prime mover with respect to the rate of rotation of said output gear.

2. The continuously variable, regenerative transmission of claim 1 in which said transfer means comprises an idler gear.

3. The continuously variable, regenerative transmission of claim 1 in which said transfer means comprises a belt.

4. A continuously variable, regenerative transmission mechanically disposed intermediate a prime mover source of variable rotational power and variable unidirectional rotational speed output and a geared output shaft having a variable rotational rate and variable rotational direction, said regenerative transmission comprising:

(A) a continuously variable transmission assembly including;

(1) first and second pulley assemblies, each said pulley assembly including;

(a) a pulley assembly shaft with an axis of rotation;

(b) a pair of pulley sheaves;

(c) a series of belt engaging elements, each of said belt engaging elements having;

(i) an elongated central shank including a drive surface adapted to be engaged by said drive belt;

(ii) a first bearing region at a first end of said central shank; and

(iii) a second bearing region at a second end of said central shank;

(d) each of said pulley sheaves including;

a pair of relatively movable guideway disks lying alongside each other in juxtaposition, an inner guideway disk of each said pair including a first series of spiral guideways extending radially in one direction, an outer guideway disk of each said pair including a second series of spiral guideways extending radially in a second direction, said first and second series of spiral guideways providing intersections for capturing and locating said bearing regions of said belt engaging elements, said intersections providing locations for said bearing regions to establish radial positions of said belt engaging elements with respect to said shaft;

(e) means connecting said inner guideway disks of said pulley sheaves together to establish an inner guideway disk set which rotates about the axis of said shaft;

(f) means connecting said outer guideway disks of said pulley sheaves together to establish an outer guideway disk set which rotates about the axis of said shaft;

(g) means coupling at least one of said guideway disks to said shaft for rotation therewith; and

(h) means for adjusting the rotational position on said shaft between said inner guideway disk set and said outer guideway disk set to establish the radial position of said belt engaging elements of said pulley assembly; and

(2) a flat drive belt coupling said first and second pulley assemblies;

(B) an input shaft coupled with said assembly shaft of said first pulley assembly and to a prime mover;

(C) a sun gear shaft coupled with said assembly shaft of said second pulley assembly, said sun gear shaft carrying a high gear rotating therewith;

(D) a first planetary gear assembly coupled to said sun gear shaft, said planetary gear assembly including;

(1) a sun gear rotating with said sun gear shaft;

(2) a planet carrier rotatably about said sun gear shaft axis;

(3) a plurality of planet gears carried by said first planet carrier and meshing with said sun gear;

(4) a ring gear meshing with said set of planet gears; and

(5) a low gear rotating with said first ring gear;

(E) transfer means coupling rotation of said input shaft to said planet carrier;

(F) an output shaft, said output shaft having an output gear rotating therewith;

(G) a high output gear rotatably carried by said output shaft, said high output gear being coupled to said high gear;

(H) a low output gear rotatably carried by said output shaft, said low output gear being coupled to said low gear;

(I) a high clutch adapted to selectively couple said high output gear to said output shaft;

(J) a low clutch adapted to selectively couple said low output gear to said output shaft; and

(K) control means including;

(1) means to sense the rate of rotation of said output gear, on said output shaft;

(2) means to give a desired rotational direction of said output gear, on said output shaft;

(3) means to sense the rotational direction of said output gear, on said output shaft;

(4) means to sense the rate of rotation of a prime mover;

(5) means to adjust the rate of rotation of a prime mover;

(6) means to actuate at least one of said high and low clutches; and

(7) means to adjust said first and second actuators to obtain a belt slip value that corresponds to a pulley torque versus belt tension which results in rotation of said output gear in the desired direction at a rate according to a predetermined ratio of the rate of rotation of the prime mover with respect to the rate of rotation of said output gear.

5. The continuously variable, regenerative transmission of claim 4 in which said means for adjusting the angular relationship between said inner guideway disk set and said outer guideway disk set of at least one of said pulley assemblies comprises:

(A) a second planetary gear system mechanically disposed intermediate said inner guideway disk set and said outer guideway disk set, said second planetary gear system including;

(1) a second sun gear coupled to said inner guideway disk set;

(2) a third sun gear coupled to said outer guideway disk set;

(3) said second and third sun gears being axially aligned;

(4) a rotatable planet carrier with a variable angular position relative to said sun gears;

(5) a second set of planet gears meshing with one of said second and third sun gears, said second set of planet gears being supported on said rotatable planet carrier;

(6) a set of star gears meshing with the other of said second and third sun gears, each of said star gears being supported in fixed angular position with respect to said other of said second and third sun gears;

(7) an internal ring gear meshing with said second set of planet gears and said star gears; and

(8) means for selectively changing the angular relationship between the said rotatable planet carrier and said star gears.

6. The continuously variable, regenerative transmission of claim 5 in which said means for selectively changing the angular relationship between said second planet carrier and said star gears further includes:

(A) an external ring gear carried by said second planet carrier;

(B) a pinion meshing with said external ring gear; and

(C) means for selectively rotating said pinion.

7. The continuously variable, regenerative transmission of claim 6 in which said means for selectively rotating said pinion includes a reversible electric motor-generator.

8. The continuously variable, regenerative transmission of claim 6 in which said means for selectively rotating said pinion includes a reversible hydraulic motor-pump unit.

9. The continuously variable regenerative transmission of claim 5 which further includes a gear system mechanically disposed intermediate one of said second and third sun gears and the one of said inner or outer guideway disk sets to which said one sun gear is coupled, differentially coupling:

A. one of said second or third sun gears;

B. said inner guideway disk structure; and

C. said outer guideway disk structure;

said differential gear system giving a smaller degree of change to the angular relationship between said inner and outer guideway disk sets than the change in angular relationship between the said second and third sun gears when coupled directly to said inner and outer guideway disk sets.

10. The continuously variable, regenerative transmission of claim 9 in which said means for selectively changing the angular relationship between said second planet carrier and said star gears further includes:

(A) an external ring gear carried by said planet carrier;

(B) a pinion meshing with said external ring gear; and

(C) means for selectively rotating said pinion.

11. The continuously variable, regenerative transmission of claim 10 in which said means for selectively rotating said pinion includes a reversible electric motor-generator unit.

12. The continuously variable, regenerative transmission of claim 10 in which said means for selectively rotating said pinion includes a reversible hydraulic motor-pump unit.

13. The continuously variable, regenerative transmission of claim 9 in which said differential gear system comprises a harmonic drive.

14. The continuously variable, regenerative transmission of claim 13 in which said means for selectively changing the angular relationship between said second planet carrier and said star gears further includes:

(A) an external ring gear carried by said planet carrier;

(B) a pinion meshing with said external ring gear; and

(C) means for selectively rotating said pinion.

15. The continuously variable transmission of claim 13 in which said means for selectively rotating said pinion includes a reversible electric motor-generator unit.

16. The continuously variable transmission of claim 13 in which said means for selectively rotating said pinion includes a reversible hydraulic motor-pump unit.

17. The continuously variable, regenerative transmission of claim 4 in which said transfer means comprises an idler gear.

18. The continuously variable, regenerative transmission of claim 4 in which said transfer means comprises a belt.

19. The continuously variable, regenerative transmission of claim 5 in which said transfer means comprises an idler gear.

20. The continuously variable, regenerative transmission of claim 5 in which said transfer means comprises a belt.

21. A continuously variable transmission assembly including:

(A) a first variable diameter pulley;

(B) a first actuator for establishing the diameter of said first variable diameter pulley;

(C) a second variable diameter pulley;

(D) a second actuator for establishing the diameter of said second variable diameter pulley;

(E) a belt coupling said first and second variable diameter pulleys; and

(F) means to measure and calculate belt slip in said pulleys when rotating to give pulley torque in said power transmitting belt driven pulley system, said means including;

(1) means to measure the radius of the pulley surface of each pulley;

(2) means to measure the distance from each pulley surface to the mean load bearing location of said belt at a pulley torque similar to or less than that obtained when operating the engine input at idle or minimum speed;

(3) means to measure the speed of each pulley in RPM; and

(4) means to utilize the said measurements to determine belt slippage during operation according to the formula;

percent slip=(1-N₂ RC₂)/(N₁ RC₁) 100%

wherein

R=the radius of a pulley surface in feet;

a=the distance of a pulley surface to the load bearing location of said belt;

N=the speed of a pulley in RPM;

= the driving pulley;

2=the driven pulley

RC₁ =R₁ +a

RC₂ =R₂ +a.

22. The continuously variable transmission assembly of claim 21 wherein said means to measure and calculate belt slip additionally includes means to utilize said measurement of belt slip to operate means on said pulleys to alter the pulley radius ratio and belt tension.

23. The continuously variable transmission of claim 21 or claim 22 wherein said belt is a flat belt.

24. A transmission assembly including:

(A) a first fixed diameter pulley;

(B) a second fixed diameter pulley;

(C) a belt coupling said first and second fixed diameter pulleys;

(D) means to measure and calculate belt slip in said pulleys when rotating to give pulley torque in said power transmitting belt driven pulley system, said means including;

(1) means to measure the radius of the pulley surface of each pulley;

(2) means to measure the distance from each pulley surface to the mean load bearing location of said belt at very low torque;

(3) means to measure the speed of each pulley in RPM; and

(4) means to utilize the said measurements to determine belt slippage during operation according to the formula;

space="preserve" listing-type="equation">percent slip=(1-N.sub.2 RC.sub.2)/(N.sub.1 RC.sub.1) 100%

wherein

R=the radius of a pulley surface in feet;

a=the distance of a pulley surface to the load bearing location of said belt;

N=the speed of a pulley in RPM;

= the driving pulley;

2=the driven pulley

RC₁ =R₁ +a

RC₂ =R₂ +a.