Source: http://www.google.com/patents/US6629577?ie=ISO-8859-1
Timestamp: 2015-08-01 14:04:16
Document Index: 632110958

Matched Legal Cases: ['application No. 09', 'application No. 09', 'application No. 09', 'application No. 09', 'application No. 09', 'application No. 09', 'application No. 09', 'application No. 09', 'application No. 09', 'application No. 09']

Patent US6629577 - Driving apparatus for speed changing and steering of a vehicle - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsA driving apparatus for speed changing and steering of a vehicle consists of a first driving unit for speed changing in advancing and reversing and a second driving unit for steering, which are arranged in a longitudinal row and are attached to a vehicle chassis. Each of the first driving unit and the...http://www.google.com/patents/US6629577?utm_source=gb-gplus-sharePatent US6629577 - Driving apparatus for speed changing and steering of a vehicleAdvanced Patent SearchPublication numberUS6629577 B1Publication typeGrantApplication numberUS 09/700,147PCT numberPCT/US1998/013811Publication dateOct 7, 2003Filing dateJul 2, 1998Priority dateJul 2, 1998Fee statusLapsedAlso published asUS6591936, US6648094, US6651770, US6874593, US20010045316, US20010045317, US20020007980, US20040060270Publication number09700147, 700147, PCT/1998/13811, PCT/US/1998/013811, PCT/US/1998/13811, PCT/US/98/013811, PCT/US/98/13811, PCT/US1998/013811, PCT/US1998/13811, PCT/US1998013811, PCT/US199813811, PCT/US98/013811, PCT/US98/13811, PCT/US98013811, PCT/US9813811, US 6629577 B1, US 6629577B1, US-B1-6629577, US6629577 B1, US6629577B1InventorsRobert Abend, Kerwyn StollOriginal AssigneeTuff Torq CorporationExport CitationBiBTeX, EndNote, RefManPatent Citations (99), Non-Patent Citations (25), Referenced by (3), Classifications (10), Legal Events (6) External Links: USPTO, USPTO Assignment, EspacenetDriving apparatus for speed changing and steering of a vehicle
US 6629577 B1Abstract
What is claimed is: 1. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means. 2. The transaxle apparatus as set forth in claim 1, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions, wherein said first and second steering output shafts are driven by said second transmission so as to generate a difference of rotation between said first and second axles. 3. The transaxle apparatus as set forth in claim 1, wherein said first and second axles of said first driving unit are extended perpendicularly to the traveling direction of said vehicle so as to be opposite to each other, and said first and second steering output shafts are extended in parallel to said first and second axles.
4. The transaxle apparatus as set forth in claim 3, wherein said first and second driving units are aligned along the traveling direction of said vehicle.
5. The transaxle apparatus as set forth in claim 4, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions so that said first and second drive trains are disposed oppositely to each other with respect to said first and second driving units, wherein said first and second steering output shafts are driven by said second transmission so as to generate a difference of rotation between said first and second axles. 6. The transaxle apparatus as set forth in claim 1, wherein said first transmission is a hydrostatic stepless transmission comprising a hydraulic pump and a hydraulic motor fluidly connected with each other.
7. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein said first transmission is a hydrostatic stepless transmission comprising a hydraulic pump and a hydraulic motor fluidly connected with each other and wherein said driving output setting means comprises a movable swash plate of said hydrostatic stepless transmission serving as said first transmission. 8. The transaxle apparatus as set forth in claim 1, wherein said driving output setting means interlocks with a speed control operating member provided on a driver's portion of said vehicle.
9. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein said driving output setting means interlocks with a speed control operating member provided on a driver's portion of said vehicle and wherein a linkage interposed between said driving output setting means and said speed control operating member is disposed below said driver's portion of said vehicle. 10. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein said driving output setting means interlocks with a speed control operating member provided on a driver's portion of said vehicle and wherein said driving output setting means comprises a lever rotated along the traveling direction of said vehicle according to the operation of said speed control operating member. 11. The transaxle apparatus as set forth in claim 10, wherein said lever of said driving output setting means interlocks with a movable swash plate of a hydrostatic stepless transmission serving as said first transmission comprising a hydraulic pump and a hydraulic motor fluidly connected with each other.
12. The transaxle apparatus as set forth in claim 8, wherein said speed control operating member is a foot pedal.
13. The transaxle apparatus as set forth in claim 12, wherein said foot pedal comprises a forward driving pedal and a backward driving pedal, and wherein a direction of output rotation of said first transmission is determined according to which is pressed, said forward driving pedal or said backward driving pedal.
14. The transaxle apparatus as set forth in claim 1, wherein said first driving unit comprises a first differential mechanism differentially connecting said first and second axles, so that the output of said first transmission is transmitted to said first and second axles through said first differential mechanism.
15. The transaxle apparatus as set forth in claim 14, wherein said first driving unit comprises a common housing so that said first transmission and said first differential mechanism are disposed in said common housing.
16. The transaxle apparatus as set forth in claim 14, wherein said first driving unit comprises a housing so that said first transmission is disposed in said housing and said first differential mechanism is disposed outside said housing.
17. The transaxle apparatus as set forth in claim 1, wherein said second transmission is a hydrostatic stepless transmission comprising a hydraulic pump and a hydraulic motor fluidly connected with each other.
18. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein said second transmission is a hydrostatic stepless transmission comprising a hydraulic pump and a hydraulic motor fluidly connected with each other and wherein said steering output setting means comprises a movable swash plate of said hydrostatic stepless transmission serving as said second transmission. 19. The transaxle apparatus as set forth in claim 1, wherein said steering output setting means interlocks with a steering operating member provided on a driver's portion of said vehicle.
20. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein said steering output setting means interlocks with a steering operating member provided on a driver's portion of said vehicle and wherein a linkage interposed between said steering output setting means and said steering operating member is disposed below said driver's portion of said vehicle. 21. A transaxle apparatus for speed changing and steeling of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein said steering output setting means interlocks with a steering operating member provided on a driver's portion of said vehicle and wherein said steering output setting means comprises a lever rotated along the traveling direction of said vehicle according to the operation of said steering operating member. 22. The transaxle apparatus as set forth in claim 21, wherein said lever of said steering output setting means interlocks with a movable swash plate of a hydrostatic stepless transmission serving as said second transmission comprising a hydraulic pump and a hydraulic motor fluidly connected with each other.
23. The transaxle apparatus as set forth in claim 19, wherein said steering operating member is a steering wheel.
24. The transaxle apparatus as set forth in claim 23, wherein said steering wheel is rotatable from a straight traveling position in two opposite directions for left-turning and right-turning of said vehicle, and wherein a direction of output rotation of said second transmission is determined according to which direction said steering wheel is rotated from said straight traveling position.
25. The transaxle apparatus as set forth in claim 1, wherein said second driving unit comprises a second differential mechanism differentially connecting said first and second steering output shafts, so that the output of said second transmission is transmitted to said first and second steering output shafts through said second differential mechanism.
26. The transaxle apparatus as set forth in claim 25, wherein said second driving unit comprises a common housing so that said second transmission and said second differential mechanism are disposed in said common housing.
27. The transaxle apparatus as set forth in claim 25, wherein said second driving unit comprises a housing so that said second transmission is disposed in said housing and said second differential mechanism is disposed outside said housing.
28. The transaxle apparatus as set forth in claim 1, wherein said first driving unit comprises a first differential mechanism differentially connecting said first and second axles, so that the output of said first transmission is transmitted to said first and second axles through said first differential mechanism, and wherein said second driving unit comprises a second differential mechanism differentially connecting said first and second steering output shafts, so that the output of said second transmission is transmitted to said first and second steering output shafts through said second differential mechanism.
29. The transaxle apparatus as set forth in claim 25, wherein said first driving unit comprises a common first housing so that said first transmission and said first differential mechanism are disposed in said common first housing of said first driving unit, and wherein said second driving unit comprises a second common housing so that said second transmission and said second differential mechanism are disposed in said second common housing of said second driving unit.
30. The transaxle apparatus as set forth in claim 29, wherein said first and second driving units are aligned along the traveling direction of said vehicle, wherein said first and second axles supported by said first housing are extended perpendicularly to the traveling direction of said vehicle in opposite to each other, and wherein said first and second steering output shafts supported by said second housing are extended in parallel to said first and second axles, so that said first axle and said first steering output shaft are disposed on one side of said first and second housings and said second axle and said second steering output shaft are disposed on the other side of said first and second housings.
31. The transaxle apparatus as set forth in claim 30, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions so that said first and second drive trains are disposed oppositely to each other with respect to said first and second housings, wherein said first and second steering output shafts are driven by said second transmission so as to generate a difference of rotation between said first and second axles. 32. The transaxle apparatus as set forth in claim 28, wherein said first driving unit comprises a first housing so that said first transmission is disposed in said first housing and said first differential mechanism is disposed outside said first housing, and wherein said second driving unit comprises a second housing so that said second transmission is disposed in said second housing and said second differential mechanism is disposed outside said second housing.
33. The transaxle apparatus as set forth in claim 32, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions, wherein said first and second steering output shafts are driven by said second transmission so as to generate a difference of rotation between said first and second axles. 34. The transaxle apparatus as set forth in claim 1, wherein said driving output setting means interlocks with a speed control operating member provided on a driver's portion of said vehicle, and wherein said steering output setting means interlocks with a steering operating member provided on said driver's portion of said vehicle.
35. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein said driving output setting means interlocks with a speed control operating member provided on a driver's portion of said vehicle, and wherein said steering output setting means interlocks with a steering operating member provided on said driver's portion of said vehicle and wherein linkages interposed between said driving output setting means and said speed control operating member and interposed between said steering output setting means and said steering operating member are disposed below said driver's portion of said vehicle. 36. The transaxle apparatus as set forth in claim 34, wherein said driving output setting means comprises a lever rotated along the traveling direction of said vehicle according to the operation of said speed control operating member, and wherein said steering output setting means comprises a lever rotated along the traveling direction of said vehicle according to the operation of said steering operating member.
37. The transaxle apparatus as set forth in claim 34, wherein said speed control operating member is a foot pedal and said steering operating member is a steering wheel.
38. The transaxle apparatus as set forth in claim 37, wherein said foot pedal comprises a forward driving pedal and a backward driving pedal, and wherein a direction of output rotation of said first transmission is determined according to which is pressed, said forward driving pedal or said backward driving pedal.
39. The transaxle apparatus as set forth in claim 37, wherein said steering wheel is rotatable from a straight traveling position in two opposite directions for left-turning and right-turning of said vehicle, and wherein a direction of output rotation of said second transmission is determined according to which direction said steering wheel is rotated from said straight traveling position.
40. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first transmission transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said first transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second transmission transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said second transmission determined by said steering output setting means, wherein an output shaft of said prime mover is disposed between an input shaft of said first transmission and an input shaft of said second transmission. 41. The transaxle apparatus as set forth in claim 40, wherein three pulleys respectively provided on said output shaft of said prime mover and input shafts of said first and second transmissions are bound through a single belt.
42. The transaxle apparatus as set forth in claim 41, wherein said prime mover is an engine provided with a crankshaft having a vertical axis.
43. The transaxle apparatus as set forth in claim 1, wherein at least one caster is supported by said vehicle chassis.
44. The transaxle apparatus as set forth in claim 1, wherein said vehicle is provided with a mower unit.
45. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first hydrostatic stepless transmission including a hydraulic pump and a hydraulic motor fluidly connected with each other for transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said hydraulic motor of said first hydrostatic stepless transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second hydrostatic stepless transmission including a hydraulic pump and a hydraulic motor fluidly connected with each other for transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said hydraulic motor of said second hydrostatic stepless transmission determined by said steering output setting means. 46. The transaxle apparatus as set forth in claim 45, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions, wherein said first and second steering output shafts are driven by said hydraulic motor of said second hydrostatic stepless transmission so as to generate a difference of rotation between said first and second axles. 47. The transaxle apparatus as set forth in claim 46, wherein said first and second axles of said first driving unit are extended perpendicularly to the traveling direction of said vehicle so as to be opposite to each other, and said first and second steering output shafts are extended in parallel to said first and second axles.
48. The transaxle apparatus as set forth in claim 47, wherein said first and second driving units are aligned along the traveling direction of said vehicle.
49. The transaxle apparatus as set forth in claim 48, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions so that said first and second drive trains are disposed oppositely to each other with respect to said first and second driving units, wherein said first and second steering output shafts are driven by said hydraulic motor of said second hydrostatic stepless transmission so as to generate a difference of rotation between said first and second axles. 50. The transaxle apparatus as set forth in claim 45, wherein said first driving unit comprises a first differential mechanism differentially connecting said first and second axles, so that the output of said hydraulic motor of said first hydrostatic stepless transmission is transmitted to said first and second axles through said first differential mechanism, and wherein said second driving unit comprises a second differential mechanism differentially connecting said first and second steering output shafts, so that the output of said hydraulic motor of said second hydrostatic stepless transmission is transmitted to said first and second steering output shafts through said second differential mechanism.
51. The transaxle apparatus as set forth in claim 50, wherein said first driving unit comprises a common first housing so that said first hydrostatic stepless transmission and said first differential mechanism are disposed in said common first housing of said first driving unit, and wherein said second driving unit comprises a second common housing so that said second hydrostatic stepless transmission and said second differential mechanism are disposed in said second common housing of said second driving unit.
52. The transaxle apparatus as set forth in claim 51, wherein said first and second driving units are aligned along the traveling direction of said vehicle, wherein said first and second axles supported by said first housing are extended perpendicularly to the traveling direction of said vehicle in opposite to each other, and wherein said first and second steering output shafts supported by said second housing are extended in parallel to said first and second axles, so that said first axle and said first steering output shaft are disposed on one side of said first and second housings and said second axle and said second steering output shaft are disposed on the other side of said first and second housings.
53. The transaxle apparatus as set forth in claim 52, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions so that said first and second drive trains are disposed oppositely to each other with respect to said first and second housings, wherein said first and second steering output shafts are driven by said hydraulic motor of said second hydrostatic stepless transmission so as to generate a difference of rotation between said first and second axles. 54. The transaxle apparatus as set forth in claim 53, wherein said first driving unit comprises a first housing so that said first hydrostatic stepless transmission is disposed in said first housing and said first differential mechanism is disposed outside said first housing, and wherein said second driving unit comprises a second housing so that said second hydrostatic stepless transmission is disposed in said second housing and said second differential mechanism is disposed outside said second housing.
55. The transaxle apparatus as set forth in claim 54, further comprising:
a first drive train interlocking said first axle and said first steering output shaft with each other so as to rotate said first axle and said first steering output shaft in the same direction, and a second drive train interlocking said second axle and said second steering output shaft with each other so as to rotate said second axle and said second steering output shaft in opposite directions, wherein said first and second steering output shafts are driven by said hydraulic motor of said second stepless transmission so as to generate a difference of rotation between said first and second axles. 56. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first hydrostatic stepless transmission including a hydraulic pump and a hydraulic motor fluidly connected with each other for transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said hydraulic motor of said first hydrostatic stepless transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second hydrostatic stepless transmission including a hydraulic pump and a hydraulic motor fluidly connected with each other for transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said hydraulic motor of said second hydrostatic stepless transmission determined by said steering output setting means, wherein said driving output setting means comprises a movable swash plate of said hydraulic pump or said hydraulic motor of said first hydrostatic stepless transmission, and wherein said steering output setting means comprises a movable swash plate of said hydraulic pump or said hydraulic motor of said second hydrostatic stepless transmission. 57. The transaxle apparatus as set forth in claim 56, wherein said movable swash plate of said driving output setting means interlocks with a speed control operating member provided on a driver's portion of said vehicle, and wherein said movable swash plate of said steering output setting means interlocks with a steering operating member provided on said driver's portion of said vehicle.
58. The transaxle apparatus as set forth in claim 57, wherein linkages interposed between said movable swash plate of said driving output setting means and said speed control operating member and interposed between said movable swash plate of said steering output setting means and said steering operating member are disposed below said driver's portion of said vehicle.
59. The transaxle apparatus as set forth in claim 57, wherein said driving output setting means comprises a lever rotated along the traveling direction of said vehicle according to the operation of said speed control operating member, and wherein said steering output setting means comprises a lever rotated along the traveling direction of said vehicle according to the operation of said steering operating member.
60. The transaxle apparatus as set forth in claim 57, wherein said speed control operating member is a foot pedal and said steering operating member is a steering wheel.
61. The transaxle apparatus as set forth in claim 60, wherein said foot pedal comprises a forward driving pedal and a backward driving pedal, and wherein a direction of output rotation of said hydraulic motor of said first hydrostatic stepless transmission is determined according to which is pressed, said forward driving pedal or said backward driving pedal.
62. The transaxle apparatus as set forth in claim 60, wherein said steering wheel is rotatable from a straight traveling position in two opposite directions for left-turning and right-turning of said vehicle, and wherein a direction of output rotation of said hydraulic motor of said second hydrostatic stepless transmission is determined according to which direction said steering wheel is rotated from said straight traveling position.
63. A transaxle apparatus for speed changing and steering of a vehicle, comprising:
a vehicle chassis; a prime mover mounted on said vehicle chassis; a pair of drive wheels; a first driving unit for driving said pair of drive wheels forwardly and backwardly at various speeds, said first driving unit comprising, a pair of first and second axles differentially connected with each other, said pair of drive wheels being mounted onto said respective first and second axles, a first hydrostatic stepless transmission including a hydraulic pump and a hydraulic motor fluidly connected with each other for transmitting power from said prime mover to said first and second axles, and driving output setting means, wherein said first and second axles are driven according to a direction and speed of output rotation of said hydraulic motor of said first hydrostatic stepless transmission determined by said driving output setting means; and a second driving unit for generating a difference of rotary speed between said pair of drive wheels so as to steer a vehicle, said second driving unit comprising, a pair of first and second steering output shafts differentially connected with each other, a second hydrostatic stepless transmission including a hydraulic pump and a hydraulic motor fluidly connected with each other for transmitting power from said prime mover to said first and second steering output shafts, and steering output setting means, wherein said first and second steering output shafts are driven according to a direction and speed of output rotation of said hydraulic motor of said second hydrostatic stepless transmission determined by said steering output setting means, wherein an output shaft of said prime mover is disposed between an input shaft of said first transmission and an input shaft of said second transmission. 64. The transaxle apparatus as set forth in claim 63, wherein three pulleys respectively provided on said output shaft of said prime mover and input shafts of said first and second transmissions are bound through a single belt.
65. The transaxle apparatus as set forth in claim 64, wherein said prime mover is an engine provided with a crankshaft having a vertical axis.
66. The transaxle apparatus as set forth in claim 45, wherein at least one caster is supported by said vehicle chassis.
67. The transaxle apparatus as set forth in claim 45, wherein said vehicle is provided with a mower unit.
68. A vehicle comprising:
a vehicle chassis; a prime mover mounted on a rear portion of said vehicle chassis; a pair of first and second drive wheels; a first axle coupled with said first drive wheel; a second axle coupled with said second drive wheel; a transaxle apparatus supported by said vehicle chassis and supporting said first and second axles for speed changing and steering of said vehicle, said transaxle apparatus including a driving transmission for driving said vehicle and a steering transmission, said driving transmission drivingly connecting said prime mover to said first and second axles for rotating said first and second drive wheels at various speeds forwardly and backwardly, a manually operable first output regulating member constituting said driving transmission for controlling the speed and direction of output rotation of said driving transmission, a steering transmission for turning said vehicle, said steering transmission drivingly connecting said prime mover to said first and second axles for accelerating one of said first and second drive wheels and decelerating the other of said first and second drive wheels, and a manually operable second output regulating member constituting said steering transmission for controlling the speed and direction of output rotation of said steering transmission; a steering wheel for manual operation of said second regulating member, said steering wheel provided with a straight driving position for stopping the output rotation of said second transmission and being rotatable from said straight driving position; and a linkage interposed between said steering wheel and said second regulating member, said linkage including a stem of said steering wheel, a first lever interlocking with said stem, a control shaft constituting said second output regulating member, said control shaft provided with a neutral position corresponding to said straight driving position and being rotatable in opposite directions from said neutral position, a second lever interlocking with said control shaft, and a link connecting said first lever to said second lever. 69. The vehicle according to claim 68, wherein said first lever is a fan-shaped gear.
70. The vehicle according to claim 69, further comprising: a pinion provided in said stem, said pinion engaging with said fan-shaped gear.
71. The vehicle according to claim 68, wherein said second lever is a control arm fixed on said control shaft.
72. A vehicle comprising:
a vehicle chassis; a prime mover mounted on a rear portion of said vehicle chassis; a pair of first and second drive wheels; a first axle coupled with said first drive wheel; a second axle coupled with said second drive wheel; a transaxle apparatus supported by said vehicle chassis and supporting said first and second axles for speed changing and steering of said vehicle, said transaxle apparatus including a driving transmission for driving said vehicle and a steering transmission, said driving transmission drivingly connecting said prime mover to said first and second axles for rotating said first and second drive wheels at various speeds forwardly and backwardly, a manually operable first output regulating member constituting said driving transmission for controlling the speed and direction of output rotation of said driving transmission, a steering transmission for turning said vehicle, said steering transmission drivingly connecting said prime mover to said first and second axles for accelerating one of said first and second drive wheels and decelerating the other of said first and second drive wheels, and a manually operable second output regulating member constituting said steering transmission for controlling the speed and direction of output rotation of said steering transmission; a steering operation means for manual operation of said second regulating member; and a mechanical linkage interposed between said steering operation means and said second regulating member. Description
With regard to the transmitting mechanism between an output shaft of the prime mover and the input shafts of the first and second HSTs of the first and second driving units, the output shaft is.disposed between the input shafts of the first and second HST. Pulleys fixed onto the output shaft of the prime mover and the two input shafts of the first and second HSTs are bound with a single belt. Accordingly, the space required for the transmitting mechanism is small, thereby allowing for a more compact vehicle and the cost of production thereof is reduced due to the use of a single belt.
FIG. 8 is a schematic side view showing another entire lawn mower provided with the driving apparatus of the present invention, wherein a cutting deck is provided in front of the vehicle thereof, and
A first input shaft 25 projects from a housing 23 of first driving unit 21 and a second input shaft 26 projects from a housing 24 of second driving unit 22.
A first input pulley 27 and a fan 39 is fixed onto first input shaft 25 and a second input pulley 28 and another fan 39 is fixed onto second input shaft 26. Output pulley 20 and a tension pulley 29 are disposed in a space between first and second input pulleys 27 and 28. All the pulleys 20, 27 and 28 are tied together with a single belt 30, so that first and second input shafts 25 and 26 can receive the power of engine 11 simultaneously. Tension pulley 29 is pushed against belt 30.
A pair of first differential output shafts (axles) 40L and 4OR project respectively from both lateral sides of housing 23 of first driving unit 21. Sprockets 41L and 41R are fixed respectively onto first differential output shafts 40L and 40R. Rear wheels 43 are fixed respectively onto first differential output shafts 40L and 40R so as to be disposed outside of sprockets 41L and 41R, respectively.
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CO., LTD., JAPANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:TUFF TORQ CORPORATION;REEL/FRAME:021018/0038Effective date: 20080520May 16, 2011REMIMaintenance fee reminder mailedOct 7, 2011LAPSLapse for failure to pay maintenance feesNov 29, 2011FPExpired due to failure to pay maintenance feeEffective date: 20111007RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services