Static hydraulic continuously variable transmission

• US 4,845,951 A
• Filed: 02/05/1988
• Issued: 07/11/1989
• Est. Priority Date: 06/28/1985
• Status: Expired due to Term

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Yoshida, Yoshihiro, Saito, Mitsuru, Ito, Kazuhito, Hayashi, Tsutomu
• Primary Examiner(s): Look, Edward K.
• Application Number:
  US07/150,442
• Time in Patent Office: 522 Days
• Field of Search: 91/461, 91/437, 91/438, 91/506, 60/487, 60/488, 60/489, 60/490, 60/468, 60/494, 137/636, 137/625.69, 188/300, 267/64.12
• US Class Current: 60/488
• CPC Class Codes: F16H 39/14 with cylinders carried in rotary cylinder blocks or cylinder-bearing members
• CPC Class Codes: F16H 61/40 hydrostatic
• CPC Class Codes: F16H 61/423 Motor capacity control by fluid pressure control means

Abstract

A static hydraulic continuously variable transmission includes a cylinder block which is secured to an output shaft and comprises a pump cylinder of a hydraulic pump and a motor cylinder of a hydraulic motor, these cylinders being connected to each other, wherein, a number of pump cylinder bores and a number of motor cylinder bores are annularly arranged respectively in the pump cylinder and the motor cylinder and the transferring of a working oil between the group of the pump cylinder bores and the group of the motor cylinder bores is conducted through the medium of a pair of oil chambers which are concentrically provided around the output shaft communincation between these cylinder bores is controlled by a number of first and second dispensing valves extending between both the oil chambers and adapted to be reciprocally radially moved. There is no relatively sliding portion between the pump cylinder and the motor cylinder, making the transferring of the working oil reliable and providing a high transmitting efficiency.

Claims

1. A static hydraulic continuously variable transmission including a hydraulic closed circuit formed between a swashplate type hydraulic pump and a swashplate type hydraulic motor, wherein:

a cylinder block comprising a pump cylinder in said hydraulic pump and a motor cylinder in said hydraulic motor which are interconnected is secured to an output shaft;

a pair of annular oil chambers are concentrically defined around said output shaft between a number of annularly arranged cylinder bores of said pump cylinder and a number of annularly arranged cylinder bores of said motor cylinder;

a number of first dispensing valves and a number of second dispensing valves are radially arranged respectively, said first dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said pump cylinder respectively into communication with said oil chambers, and said second dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said motor cylinder respectively into communication with said oil chambers;

a common first eccentric ring is engaged with said individual first dispensing valves at positions outside of said cylinder block for imparting the reciprocal movement to said dispensing valves with the relative rotation between said cylinder block and an input member of said hydraulic pump; and

a common second eccentric ring is engaged with said individual second dispensing valves at positions outside of said cylinder block for imparting the reciprocal movement to said dispensing valves with the rotation of the cylinder block;

whereby each cylinder bore of said pump cylinder is brought into communication with one of said oil chambers during the discharge stroke thereof and with the other chamber during the suction stroke thereof, while each cylinder bore of said motor cylinder is brought into communication with said one of said oil chambers during the expansion stroke thereof and with said other chamber during the contraction stroke thereof.

2. A static hydraulic continuously variable transmission according to claim 1, wherein the discharge port of a supplement pump is connected to said other oil chamber through a check valve for blocking the issuing of a working oil out of said other chamber.

4. A static hydraulic continuously variable transmission according to claim 1, wherein at least one of said first and second dispensing valves comprises an operating portion engaging the corresponding first or second eccentric ring and a valve portion provided independently of said operating portion and slidably fitted in the valve bore made in said cylinder block, said valve portion and operating portion slidably abutting against each other.

5. A static hydraulic continuously variable transmission according to claim 1, wherein a follower ring is engaged with the inner ends of each said first and second dispensing valves.

6. A static hydraulic continuously variable transmission according to claim 5, wherein said follower ring is disposed concentrically to the corresponding first or second eccentric ring.

3. A static hydraulic continuously variable transmission including a hydraulic closed circuit formed between a swashplate type hydraulic pump and a swashplate type hydraulic motor, wherein:

a cylinder block comprising a pump cylinder in said hydraulic pump and a motor cylinder in said hydraulic motor which are interconnected is secured to an output shaft;

a pair of annular oil chambers are concentrically defined around said output shaft between a number of annularly arranged cylinder bores of said pump cylinder and a number of annularly arranged cylinder bores of said motor cylinder;

a number of first dispensing valves and a number of second dispensing valves are radially arranged respectively, said first dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said pump cylinder respectively into communication with said oil chambers, and said second dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said motor cylinder respectively into communication with said oil chambers;

a common first eccentric ring is engaged with said individual first dispensing valves for imparting the reciprocal movement to said dispensing valves with the relative rotation between said cylinder block and an input member of said hydraulic pump; and

a common second eccentric ring is engaged with said individual second dispensing valves for imparting the reciprocal movement to said dispensing valves with the rotation of the cylinder block;

whereby each cylinder bore of said pump cylinder is brought into communication with one of said oil chambers during the discharge stroke thereof and with the other chamber during the suction stroke thereof, while each cylinder bore of said motor cylinder is brought into communication with said one of said oil chambers during the expansion stroke thereof and with said other chamber during the contraction stroke thereof;

wherein said output shaft is fitted in said cylinder block at the central portion thereof, and a sleeve is fitted over the outer peripheral surface of said cylinder block, and wherein said pair of oil chambers are defined between the respective opposed surfaces of said cylinder block, output shaft and sleeve.

7. A static hydraulic continuously variable transmission including a hydraulic closed circuit formed between a swashplate type hydraulic pump and a swashplate type hydraulic motor, wherein:

a cylinder block comprising a pump cylinder in said hydraulic pump and a motor cylinder in said hydraulic motor which are interconnected is secured to an output shaft;

a pair of annular oil chambers are concentrically defined around said output shaft between a number of annularly arranged cylinder bores of said pump cylinder and a number of annularly arranged cylinder bores of said motor cylinder;

a number of first dispensing valves and a number of second dispensing valves are radially arranged respectively, said first dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said pump cylinder respectively into communication with said oil chambers, and said second dispensing vlaves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said motor cylinder respectively into communication with said oil chambers;

a common first eccentric ring is engaged with said individual first dispensing valves for imparting the reciprocal movement to said dispensing valves with the relative rotation between said cylinder block and an input member of said hydraulic pump; and

a common second eccentric ring is engaged with said individual second dispensing valves for imparting the reciprocal movement to said dispensing valves with the rotation of the cylinder block;

whereby each cylinder bore of said pump cylinder is brought into communication with one of said oil chambers during the discharge stroke thereof and with the other chanber during the suction stroke thereof, while each cylinder bore of said motor cylinder is brought into communication with said one of said oil chambers during the expansion stroke thereof and with said other chamber during the contraction stroke thereof;

wherein a plurality of clutch valves are radially arranged between said first and second dispensing valves, and a clutch control ring is engaged with the outer ends of the clutch valves, and wherein means are mounted between said first and second eccentric rings and said clutch control ring for preventing mutual interference.

8. A static hydraulic continuously variable transmission including a hydraulic closed circuit formed between a swashplate type hydraulic pump and a swashplate type hydraulic motor, wherein:

a cylinder block comprising a pump cylinder in said hydraulic pump and a motor cylinder in said hydraulic motor which are interconnected is secured to an output shaft;

a pair of annular oil chambers are concentrically defined around said output shaft between a number of annularly arranged cylinder bores of said pump cylinder and a number of annularly arranged cylinder bores of said motor cylinder;

a number of first dispensing valves and a number of second dispensing valves are radially arranged respectively, said first dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said pump cylinder respectively into communication with said oil chambers, and said second dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said motor cylinder respectively into communication with said oil chambers;

a common first eccentric ring is engaged with said individual first dispensing valves for imparting the reciprocal movement to said dispensing valves with the relative rotation between said cylinder block and an input member of said hydraulic pump; and

a common second eccentric ring is engaged with said individual second dispensing valves for imparting the reciprocal movement to said dispensing valves with the rotation of the cylinder block;

whereby each cylinder bore of said pump cylinder is brought into communication with one of said oil chambers during the discharge stroke thereof and with the other chamber during the suction stroke thereof, while each cylinder bore of said motor cylinder is brought into communication with said one of said oil chambers during the expansion stroke thereof and with said other chamber during the contraction stroke thereof;

wherein a follower ring is engaged with the inner ends of each said first and second dispensing valves; and

wherein a plurality of clutch valves are radially arranged between said first and second dispensing valves, a clutch control ring being engaged with the outer ends of the clutch valves and a follower ring being engaged with the inner ends of said clutch valves, and means are mounted between the respective follower rings of said first and second dispensing valves and said clutch valves for preventing mutual interference.

9. A static hydraulic continuously variable transmission including a hydraulic closed circuit formed between a swashplate type hydraulic pump and swashplate type hydraulic motor, wherein:

a cylinder block comprising a pump cylinder in said hydraulic pump and a motor cylinder in said hydraulic motor which are interconnected is secured to an output shaft;

a pair of annular oil chambers are concentrically defined around said output shaft between a number of annularly arranged cylinder bores of said pump cylinder and a number of annularly arranged cylinder bores of said motor cylinder;

a number of first dispensing valves and a number of second dispensing valves are radially arranged respectively, said first dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said pump cylinder respectively into communication with said oil chambers, and said second dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said motor cylinder respectively into communication with said oil chambers;

a common first eccentric ring is engaged with said individual first dispensing valves for imparting the reciprocal movement to said dispensing valves with the relative rotation between said cylinder block and an input member of said hydraulic pump; and

a common second eccentric ring is engaged with said individual second dispensing valves for imparting the reciprocal movement to said dispensing valves with the rotation of the cylinder block;

whereby each cylinder bore of said pump cylinder is brought into communication with one of said oil chambers during the discharge stroke thereof and with the other chamber during the suction stroke thereof, while each cylinder bore of said motor cylinder is brought into communication with said one of said oil chambers during the expansion stroke thereof and with said other chamber during the contraction stroke thereof;

wherein said output shaft is fitted in said cylinder block at the central portion thereof, and a sleeve is fitted over the outer peripheral surface of said cylinder block, and wherein said pair of oil chambers are defined between the respective opposed surfaces of said cylinder block, output shaft and sleeve;

wherein a plurality of clutch valves are radially arranged between said first and second dispensing valves, and that portion of said sleeve which is penetrated by said clutch valves is in the form of a reinforcing rib, and further, a pair of reinforcing means are secured to the outer peripheral surface of said sleeve in such a manner to clamp said first and second eccentric rings therebetween from the outside.

10. A static hydraulic pressure type continuously variable transmission comprising:

a hydraulic pump having a pump cylinder;

a hydraulic motor having a motor cylinder;

a hydraulic closed circuit between said hydraulic pump and motor; and

a transmission shaft;

said pump cylinder and said motor cylinder being integrally connected with each other to form a cylinder block which is disposed on said transmission shaft;

wherein a pair of annular oil chambers are defined concentrically around said transmission shaft between a number of cylinder bores annularly arranged in said pump cylinder and a number of cylinder bores annularly arranged in said motor cylinder;

wherein a number of first dispensing valves are radially arranged and are reciprocatingly movable between respective radial inner and radial outer positions so as to alternately connect said number of cylinder bores of said pump cylinder with said pair of annular oil chambers, respectively, and a number of second dispensing valves are radially arranged and are reciprocatingly movable between respective radial inner and radial outer positions so as to alternately connect said number of cylinder bores of said motor cylinder with said pair of annular oil chambers, respectively; and

wherein a first common eccentric ring is in engagement with said first dispensing valves at positions outside of said cylinder block for imparting reciprocating motions to the first dispensing valves in response to relative rotations between said hydraulic pump and an input member, and a second common eccentric ring is in engagement with said second dispensing valves at positions outside of said cylinder block for imparting reciprocating motions to the second dispensing valves in response to rotations of said cylinder block;

said cylinder bores of the pump cylinder being communicated with one of said pair of annular oil chambers during discharge strokes thereof and with the other annular oil chamber during suction strokes thereof, said cylinder bores of the motor cylinder being communicated with said one of said pair of annular oil chambers during expansion strokes thereof and with said other annular oil chamber during contraction strokes thereof.

11. A static hydraulic pressure type continuously variable transmission according to claim 10, further comprising a supplement pump having a discharge port, said other annular oil chamber being communicated with said discharge port of said supplement pump via a check valve, which check valve blocks operation oil from flowing out of said other annular oil chamber.

12. A static hydraulic pressure type continuously variable transmission comprising:

a hydraulic pump having a pump cylinder;

a hydraulic motor having a motor cylinder;

a hydraulic closed circuit between said hydraulic pump and motor; and

a transmission shaft;

said pump cylinder and said motor cylinder being integrally connected with each other to form a cylinder block which is disposed on said transmission shaft;

wherein a pair of annular oil chambers are defined concentrically around said transmission shaft between a number of cylinder bores annularly arranged in said pump cylinder and a number of cylinder bores annularly arranged in said motor cylinder;

wherein a number of first dispensing valves are radially arranged and are reciprocatingly movable between respective radial inner and radial outer positions so as to alternately connect said number of cylinder bores of said pump cylinder with said pair of annular oil chambers, respectively, and a number of second dispensing valves are radially arranged and are reciprocatingly movable between respective radial inner and radial outer positions so as to alternately connect said number of cylinder bores of said motor cylinder with said pair of annular oil chambers, respectively; and

wherein a first common eccentric ring is in engagement with said first dispensing valves for imparting reciprocating motions to the first dispensing valves in response to relative rotations between said hydraulic pump and an input member, and a second common eccentric ring is in engagement with said second dispensing valves for imparting reciprocating motions to the second dispensing valves in response to rotations of said cylinder block;

said cylinder bores of the pump cylinder being communicated with one of said pair of annular oil chambers during discharge strokes thereof and with the other annular oil chamber during suction strokes thereof, said cylinder bores of the motor cylinder being communicated with said one of said pair of annular oil chambers during expansion strokes thereof and with said other annular oil chamber during contraction strokes thereof;

wherein a plurality of clutch valves are arranged radially between said first and second dispensing valves and a clutch control ring is in engagement with respective outer ends of said clutch valves, and wherein means are provided between said first eccentric ring, said second eccentric ring and said clutch control ring for preventing mutual interference therebetween.

13. A static hydraulic pressure type continuously variable transmission comprising:

a hydraulic pump having a pump cylinder;

a hydraulic motor having a motor cylinder;

a hydraulic closed circuit between said hydraulic pump and motor; and

a transmission shaft;

said pump cylinder and said motor cylinder being integrally connected with each other to form a cylinder block which is disposed on said transmission shaft;

wherein a pair of annular oil chambers are defined concentrically around said transmission shaft between a number of cylinder bores annularly arranged in said pump cylinder and a number of cylinder bores annularly arranged in said motor cylinder;

wherein a number of first dispensing valves are radially arranged and are reciprocatingly movable between respective radial inner and radial outer positions so as to alternately connect said number of cylinder bores of said pump cylinder with said pair of annular oil chambers, respectively, and a number of second dispensing valves are radially arranged and are reciprocatingly movable between respective radial inner and radial outer positions so as to alternately connect said number of cylinder bores of said motor cylinder with said pair of annular oil chambers, respectively; and

wherein a first common eccentric ring is in engagement with said first dispensing valves at positions outside of said cylinder block for imparting reciprocating motions to the first dispensing valves, and a second common eccentric ring is in engagement with said second dispensing valves at positions outside of said cylinder block for imparting reciprocating motions to the second dispensing valves;

said cylinder bores of the pump cylinder being communicated with one of said pair of annular oil chambers during discharge strokes thereof and with the other annular oil chamber during suction strokes thereof, said cylinder bores of the motor cylinder being communicated with said one of said pair of annular oil chambers during expansion strokes thereof and with said other annular oil chamber during contraction strokes thereof.

14. A static hydraulic pressure type continuously variable transmission comprising:

a hydraulic pump having a pump cylinder;

a hydraulic motor having a motor cylinder;

a hydraulic closed circuit between said hydraulic pump and motor; and

a transmission shaft;

said pump cylinder and said motor cylinder being integrally connected with each other to form a cylinder block which is disposed on said transmission shaft;

wherein said hydraulic closed circuit is formed integral with said cylinder block and includes a high pressure oil chamber and a low pressure oil chamber, said high and low pressure oil chambers being communicated with a number of cylinder bores arranged in said pump cylinder and a number of cylinder bores arranged in said motor cylinder, respectively, via a dispensing valve arrangement; and

wherein said dispensing valve arrangement includes dispensing valves which are disposed separately for the motor and the pump so as to be rotatable in response to rotation of the cylinder block and are operable to alternately communicate said pump cylinder bores and said motor cylinder bores with said high pressure oil chamber and said low pressure oil chamber, respectively, said dispensing valves projecting outside of said cylinder block and at projected parts thereof engaging with and being driven by a dispensing valve driving means which is disposed outside of the cylinder block.

15. A static hydraulic pressure type continuously variable transmission according to claim 14, wherein said high and low pressure oil chambers are formed annularly and one of the chambers encircles the other, and wherein said dispensing valves are reciprocatingly movable between said annular high and low pressure oil chambers.

16. A static hydraulic pressure type continuously variable transmission according to claim 15, wherein said annular high and low pressure oil chambers are disposed concentrically with respect to said transmission shaft and said dispensing valves are adapted to reciprocate between a radial outer position and a radial inner position in said cylinder block.

17. A static hydraulic pressure type continuously variable transmission according to claim 16, wherein said dispensing valve driving means comprises eccentric rings which are disposed eccentrically with respect to the axis of said cylinder block.

18. A static hydraulic pressure type continuously variable transmission according to claim 16, wherein said dispensing valves are disposed radially and said dispensing valve drive means comprises eccentric rings which are disposed eccentrically with respect to the axis of said cylinder block.

19. A static hydraulic pressure type continuously variable transmission according to claim 14, wherein said dispensing valve driving means drives said dispensing valves disposed separately for the motor and the pump in such a manner that through operation of the valves the pump cylinder bores are communicated with said high pressure oil chamber during discharge strokes thereof and with said low pressure oil chamber during suction strokes thereof while said motor cylinder bores are communicated with said high pressure oil chamber during expansion strokes thereof and with said low pressure oil chamber during contraction strokes thereof.

20. A static hydraulic pressure type continuously variable transmission according to claim 19, wherein said high and low pressure oil chambers are formed annularly and one of the chambers encircles the other, and wherein said dispensing valves are reciprocatingly movable between said annular high and low pressure oil chambers.

21. A static hydraulic pressure type continuously variable transmission according to claim 20, wherein said dispensing valves are adapted to reciprocate between a radial outer position and a radial inner position in said cylinder block.

22. A static hydraulic continuously variable transmission including a hydraulic closed circuit formed between a swashplate type hydraulic pump and a swashplate type hydraulic motor, wherein:

a cylinder block comprising a pump cylinder in said hydraulic pump and a motor cylinder in said hydraulic motor which are interconnected is secured to an output shaft;

a pair of annular oil chambers are concentrically defined around said output shaft between a number of annularly arranged cylinder bores of said pump cylinder and a number of annularly arranged cylinder bores of said motor cylinder;

a number of first dispensing valves and a number of second dispensing valves are radially arranged respectively, said first dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said pump cylinder respectively into communication with said oil chambers, and said second dispensing valves being adapted to be reciprocally moved between radially outer and inner positions to alternately bring the number of cylinder bores of said motor cylinder respectively into communication with said oil chambers;

a common first eccentric ring is engaged with said individual first dispensing valves for imparting the reciprocal movement to said dispensing valves with the relative rotation between said cylinder block and an input member of said hydraulic pump; and

a common second eccentric ring is engaged with said individual second dispensing valves for imparting the reciprocal movement to said dispensing valves with the rotation of the cylinder block;

whereby each cylinder bore of said pump cylinder is brought into communication with one of said oil chambers during the discharge stroke thereof and with the other chamber during the suction stroke thereof, while each cylinder bore of said motor cylinder is brought into communication with said one of said oil chambers during the expansion stroke thereof and with said other chamber during the contraction stroke thereof;

wherein a follower ring is engaged with the inner ends of each said first and second dispensing valves, said follower ring being disposed concentrically to the corresponding first or second eccentric ring;

wherein a plurality of clutch valves are radially arranged between said first and second dispensing valves, a clutch control ring being engaged with the outer ends of and a follower ring being engaged with the inner ends of said clutch valves, and means are mounted between the respective follower rings of said first and second dispensing valves and said clutch valves for preventing the mutual interference.

23. A static hydraulic pressure type continuously variable transmission comprising:

a hydraulic pump having a pump cylinder;

a hydraulic motor having a motor cylinder;

a hydraulic closed circuit between said hydraulic pump and said hydraulic motor; and

a transmission shaft;

said pump cylinder and said motor cylinder being integrally connected with each other to form a cylinder block and said cylinder block being disposed on said transmission shaft;

wherein said hydraulic closed circuit includes a pair of oil chambers, said oil chambers being in communication with a number of cylinder bores arranged in said pump cylinder and a number of cylinder bores arranged in said motor cylinder, respectively, via a dispensing valve arrangement;

wherein said dispensing valve arrangement includes dispensing valves which are operable to alternately communicate said pump cylinder bores and said motor cylinder bores with each of said oil chambers, said dispensing valves being driven by a dispensing valve driving means; and

wherein said dispensing valves engage with and are driven by the dispensing valve driving means at positions outside of the cylinder block.

24. A static hydraulic pressure type continuously variable transmission according to claim 23, wherein said dispensing valves project outside of the cylinder block and at projected parts thereof are driven by said driving means.

25. A hydraulically operated power transmission system comprising a swashplate type hydraulic pump and a swashplate type hydraulic motor, each of the pump and the motor including a cylinder having a number of cylinder bores annularly arranged therein, a number of plungers each slidably received in one of the cylinder bores, and a swashplate engaging those ends of the plungers which protrude from the cylinder bores,

wherein a low pressure oil chamber and a high pressure oil chamber are defined in the cylinders in a manner distanced from each other,

wherein the transfer of a working oil between the cylinder bores and the low and high pressure oil chamber is carried out during relative rotation between the cylinders and a member supporting one of the swashplates,

wherein a plurality of dispensing valves are provided in each cylinder in a radially arranged configuration for reciprocation between radially outer and inner positions to permit the respective cylinder bores to alternately communicate with the low and high pressure oil chambers,

wherein a dispensing valve driving means is provided to cause the dispensing valves to reciprocate interlockingly with the relative rotation between the one cylinder and the swashplate supporting member, and

wherein the dispensing valves engage with and are driven by the dispensing valve driving means at positions outside of the cylinders.

26. A hydraulically operated power transmission system according to claim 25, wherein the dispensing valves project outside of the cylinders and at projected parts thereof are driven by the dispensing valve drive means.

27. A hydraulically operated power transmission system according to claim 25, wherein the system is applied to a static hydraulic pressure type continuously variable transmission.

28. A hydraulically operated power transmission system according to claim 26, wherein the system is applied to a static hydraulic pressure type continuously variable transmission.