EP0624232A1 - Continuously-variable hydromechanical parallel-type transmission device - Google Patents

Continuously-variable hydromechanical parallel-type transmission device

Info

Publication number
EP0624232A1
EP0624232A1 EP93903241A EP93903241A EP0624232A1 EP 0624232 A1 EP0624232 A1 EP 0624232A1 EP 93903241 A EP93903241 A EP 93903241A EP 93903241 A EP93903241 A EP 93903241A EP 0624232 A1 EP0624232 A1 EP 0624232A1
Authority
EP
European Patent Office
Prior art keywords
pump
hydrostatic
transmission device
housing
fluid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP93903241A
Other languages
German (de)
French (fr)
Inventor
Thomas William Wielkopolski
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP0624232A1 publication Critical patent/EP0624232A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H47/00—Combinations of mechanical gearing with fluid clutches or fluid gearing
    • F16H47/02—Combinations of mechanical gearing with fluid clutches or fluid gearing the fluid gearing being of the volumetric type
    • F16H47/04—Combinations of mechanical gearing with fluid clutches or fluid gearing the fluid gearing being of the volumetric type the mechanical gearing being of the type with members having orbital motion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H37/00—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00
    • F16H37/02—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings
    • F16H37/06—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts
    • F16H37/08—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing
    • F16H37/10—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing at both ends of intermediate shafts
    • F16H2037/101—Power split variators with one differential at each end of the CVT

Definitions

  • the present invention relates to a hydro-mechanical device for the transmission of rotary motion or torque. 5 It particularly relates to a device permitting variation of the transmitted rotational speed.
  • a conventional variable hydro-mechanical gear system splits drive into two parts. One part of this drive is 0 then transmitted through a hydrostatic device to be recombined with the other part of the drive. Variation in control of the hydrostatic device controls the gear system. This invention simplifies and increases the efficiency of the gear system. 5 Disclosure of the Invention
  • the present invention concerns a transmission device in which an input is arranged to drive a hydrostatic (or hydraulic) unit directly and also to transmit drive mechanically through a housing.
  • the 0 output from the device may be in two parts, one a reaction from the house, the other a reaction from the hydrostatic unit. These two reactions may be combined through one or more planetary gear systems to provide the output drive.
  • the input directly drives the hydrostatic unit housing.
  • a reaction through a hydrostatic output drive shaft drives one torque path.
  • the resistance of this torque path turns the hydrostatic unit, so driving the other output and providing a second torque path.
  • It may include a gear pump in this form.
  • the output from the unit is transmitted to a planetary gear system and combined with the output from the * irst torque path to provide the output drive from the unit.
  • FIG. 1 is a schematic axial section through a transmission device embodying the invention
  • Fig. 2 is an alternative arrangement showing reversed drive from the hydrostatic unit
  • Fig. 3 shows a third embodiment with drive taken from the outer casing
  • Fig. 4 shows an embodiment with power output through a gear
  • Fig. 5 shows an alternative way of driving the planetary gear system
  • Fig. 6 shows an embodiment with a gear pump with different size driving and driven gears, as well as but not necessarily used with two planetary gears;
  • Fig. 7 shows a device using a bevel gear arrangement
  • Fig. 8 is a cross-section through a hydrostatic unit, in this case a gear pump.
  • Fig. 9 is a cross-section through a hydrostatic unit, in this case a double gear pump.
  • references to "input” and “output” components and the like refer to a conventional mode of usage of the devices in question.
  • FIG. 1 shows an embodiment having an outer housing
  • the input shaft 12 is tubular, and contains a displaceable control rod 13 and a pressure relief valve 16, whose function will be explained later.
  • a hydrostatic unit Inside the main housing 10, there is a hydrostatic unit with a hydrostatic unit housing 18.
  • the drive shaft 20 is fast with an oil pumping gear 32 which meshes with a gear 34 in a pumping arrangement, such that rotation of the drive shaft 20 causes the pumping of oil.
  • the oil is returned from an output side of the oil pump to the input side, preferably via a pressure relief valve 16 and/or via a flow control device.
  • a pressure relief valve 16 is controllable by longitudinal sliding of the rod 14 within the input shaft 12.
  • the driveshaft 20 When the driveshaft 20 is rotated about the axis of the input shaft 14, thus turning the gear 22 coupled to the outer housing 10, the driveshaft 20 is rotated about its own axis in the hydrostatic unit housing 18. This not only causes the oil pumping gear 32 to turn. It also rotates the gear 30 fast with the outward end of the shaft 20. This meshes with the gear 28 on the output shaft 14 and thus tends to transmit torque to that output shaft.
  • the output shaft 14 may be held fast, and drive taken from the outer housing 10.
  • the gear 22 linking the drive shaft 20 to the outer casing 10 may be an internal gear on the casing 10 or it could be an external gear on the axis of the input shaft 12.
  • Fig. 2 shows an embodiment similar to that of Fig. 1, with corresponding opponents correspondingly numbered.
  • the hydrostatic unit now includes a motor comprising gears 50 and 52. This acts to turn an internal output shaft 54, which acts to drive the gear 28 on the main output shaft 14.
  • Shafts 56 and 58 in the pump and in the motor respectively are idler shafts not connected to the drive shaft 20' and the internal output shaft 54. It can, of course, be arranged that the motor gears 50,52 should rotate at the same speed as, or a selected different speed from, the pump gears 32,34.
  • Fig. 3 shows another embodiment which is quite similar to that shown in Fig. 2. It should be appreciated that the embodiments described so far show the hydrostatic unit coupled directly to the outer housing 10. Alternatively, the coupling could be via an idler gear system.
  • the operation of the pump and motor can be controlled by control means which are not shown (such as a flow control device or a pressure relief valve as shown within the input shaft 12 in Figs. 1 and 2). If both the pump and motor are stopped, then there is direct transmission of torque from the input shaft 12 via the drive shaft 20' and gear 22 to the outer housing 10. Thus the housing rotates at the same speed as the input shaft 12. An output can be derived from the outer housing 10.
  • Fig. 4 shows an embodiment substantially as in Fig. 3 but with the output shaft 14 integral with a gear assembly for output drive.
  • Fig. 5 shows another variant in which the outer housing 10' has a reduced-diameter output shaf portion 70 at the output end, coupled to planet gears 72 of a gear train 74 to which the output shaft is also coupled.
  • output can be derived through the shaft or the gear train 74.
  • Fig. 6 shows a further variant having a hydrostatic unit whose drive is arranged through two planetary gear systems. This is exemplified in an embodiment similar to that of Fig. 1, having a pump but no motor.
  • a hydrostatic unit 80 includes a motor 82 and a pump 84. They are coupled to respective axial shafts 86,88 (that of the motor passing through that of the pump). Each of the drives 86,88 is fast with a respective one of an opposed pair of frustoconical bevel gears 90,92 (which may have the same or different numbers of teeth. These are engaged by complementary portions of a surrounding annular bevel gear 94. This is coupled to a housing 96, from which an output is derived. Input is fed to a housing 98 of the hydrostatic unit.
  • bevel gears instead of planetary gears can be applied to other embodiments too. Also generally applicable is the coaxial arrangement of the input and output of the pump (and motor).
  • Figs. 8 and 9 are sectional views through pumps.
  • Fig. 8 illustrates a pump of any of the previously-described embodiments showing a pair of gears 100,102 which might be, for example, the gears 32,34 of the pump shown in Fig. 1 or .Fig 2.
  • gears 100,102 which might be, for example, the gears 32,34 of the pump shown in Fig. 1 or .Fig 2.
  • the oil flow impelled by the gears may be as shown by the arrows.
  • Fig. 9 shows a variant in which the gears are doubled-up, to produce a mechanically balanced assembly.
  • the invention is not limited to the use of gear pumps. Any type of fluid pump and/or motor may be used, or even other types of hydrostatic coupling device e.g. a torque converter.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Retarders (AREA)
  • Structure Of Transmissions (AREA)

Abstract

La transmission d'un élément d'entrée (12) est divisée en deux parties. Une partie est transmise mécaniquement par l'intermédiaire d'un boîtier (10) à un élément de sortie (14). L'autre partie actionne un ensemble hydrostatique, par exemple, une pompe à engrennage (32, 34) pouvant faire fonctionner un moteur hydraulique (50, 52) produisant une sortie mécanique pouvant également actionner l'élément de sortie (14).The transmission of an input element (12) is divided into two parts. A portion is mechanically transmitted through a housing (10) to an output element (14). The other part actuates a hydrostatic assembly, for example, a gear pump (32, 34) which can operate a hydraulic motor (50, 52) producing a mechanical output which can also actuate the output element (14).

Description

Continuously-variable hydromechanlcal parallel-type transmission device.
Technical Field
The present invention relates to a hydro-mechanical device for the transmission of rotary motion or torque. 5 It particularly relates to a device permitting variation of the transmitted rotational speed. Background Art
A conventional variable hydro-mechanical gear system splits drive into two parts. One part of this drive is 0 then transmitted through a hydrostatic device to be recombined with the other part of the drive. Variation in control of the hydrostatic device controls the gear system. This invention simplifies and increases the efficiency of the gear system. 5 Disclosure of the Invention
Broadly, the present invention concerns a transmission device in which an input is arranged to drive a hydrostatic (or hydraulic) unit directly and also to transmit drive mechanically through a housing. The 0 output from the device may be in two parts, one a reaction from the house, the other a reaction from the hydrostatic unit. These two reactions may be combined through one or more planetary gear systems to provide the output drive.
25 In a preferred form, the input directly drives the hydrostatic unit housing. A reaction through a hydrostatic output drive shaft drives one torque path. The resistance of this torque path turns the hydrostatic unit, so driving the other output and providing a second torque path. It may include a gear pump in this form. The output from the unit is transmitted to a planetary gear system and combined with the output from the * irst torque path to provide the output drive from the unit. (Note: the designations "input" and "output" are essentially arbitrary. They relate to the usual mode of use, but the device may be used the other way round. )
Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings. Brief Description of Drawings Fig. 1 is a schematic axial section through a transmission device embodying the invention;
Fig. 2 is an alternative arrangement showing reversed drive from the hydrostatic unit;
Fig. 3 shows a third embodiment with drive taken from the outer casing;
Fig. 4 shows an embodiment with power output through a gear;
Fig. 5 shows an alternative way of driving the planetary gear system; Fig. 6 shows an embodiment with a gear pump with different size driving and driven gears, as well as but not necessarily used with two planetary gears;
Fig. 7 shows a device using a bevel gear arrangement;
Fig. 8 is a cross-section through a hydrostatic unit, in this case a gear pump; and
Fig. 9 is a cross-section through a hydrostatic unit, in this case a double gear pump. Modes for Carrying Out the Invention
In the following description, references to "input" and "output" components and the like refer to a conventional mode of usage of the devices in question.
Unless the context requires otherwise, it will be appreciated that these terms are not absolute, and could be reversed. Fig. 1 shows an embodiment having an outer housing
10 which is generally cylindrical, with a coaxial input shaft 12 and output shaft 14. The input shaft 12 is tubular, and contains a displaceable control rod 13 and a pressure relief valve 16, whose function will be explained later. Inside the main housing 10, there is a hydrostatic unit with a hydrostatic unit housing 18.
This is coupled to the input shaft 12 so as to be rotatable thereby. Off-centre, there is a drive shaft 20 parallel to the input shaft 12. This extends axially beyond the hydrostatic unit housing 18 in both directions. At the input end, it is fast with a gear 21 which engages a gear 22 which turns the outer housing 10. Adjacent the output end, the outer housing 10 has an internal ring gear 24 which turns a planetary gear 26 which, in turn, reacts against a sun gear 28 to turn the output shaft 13. On the end of the drive shaft 20 that projects at the output end, there is a fast-mounted gear 30. Within the hydrostatic unit 18, the drive shaft 20 is fast with an oil pumping gear 32 which meshes with a gear 34 in a pumping arrangement, such that rotation of the drive shaft 20 causes the pumping of oil. In this embodiment, there is no motor to be driven by pumped oil. The oil is returned from an output side of the oil pump to the input side, preferably via a pressure relief valve 16 and/or via a flow control device. As shown, a pressure relief valve 16 is controllable by longitudinal sliding of the rod 14 within the input shaft 12.
When the driveshaft 20 is rotated about the axis of the input shaft 14, thus turning the gear 22 coupled to the outer housing 10, the driveshaft 20 is rotated about its own axis in the hydrostatic unit housing 18. This not only causes the oil pumping gear 32 to turn. It also rotates the gear 30 fast with the outward end of the shaft 20. This meshes with the gear 28 on the output shaft 14 and thus tends to transmit torque to that output shaft.
In use, the output shaft 14 may be held fast, and drive taken from the outer housing 10.
The gear 22 linking the drive shaft 20 to the outer casing 10 may be an internal gear on the casing 10 or it could be an external gear on the axis of the input shaft 12.
Fig. 2 shows an embodiment similar to that of Fig. 1, with corresponding opponents correspondingly numbered. However, the hydrostatic unit now includes a motor comprising gears 50 and 52. This acts to turn an internal output shaft 54, which acts to drive the gear 28 on the main output shaft 14. Shafts 56 and 58 in the pump and in the motor respectively are idler shafts not connected to the drive shaft 20' and the internal output shaft 54. It can, of course, be arranged that the motor gears 50,52 should rotate at the same speed as, or a selected different speed from, the pump gears 32,34.
Fig. 3 shows another embodiment which is quite similar to that shown in Fig. 2. It should be appreciated that the embodiments described so far show the hydrostatic unit coupled directly to the outer housing 10. Alternatively, the coupling could be via an idler gear system.
Considering, for example, the operation of the embodiment shown in Fig. 3, the operation of the pump and motor can be controlled by control means which are not shown ( such as a flow control device or a pressure relief valve as shown within the input shaft 12 in Figs. 1 and 2). If both the pump and motor are stopped, then there is direct transmission of torque from the input shaft 12 via the drive shaft 20' and gear 22 to the outer housing 10. Thus the housing rotates at the same speed as the input shaft 12. An output can be derived from the outer housing 10.
However, rotation of the components as described tends to cause rotation of the drive shaft 20' . If such rotation is allowed, it creates pressure in the pump 32,34. Oil tends to be pumped to the motor 50,52, which acts to turn the output shaft 14. Thus two outputs are available, from the outer housing 10 and from the output shaft 14. By reducing the force from the housing 10, the oil pressure is reduced, thus affecting the transmission of torque. If the hydrostatic unit has a pressure relief control, this can be used to set torque. If there is a flow control, this can be used to set the speed. (The controls will generally act on the fluid passing between the pump and the motor. )
Fig. 4 shows an embodiment substantially as in Fig. 3 but with the output shaft 14 integral with a gear assembly for output drive.
Fig. 5 shows another variant in which the outer housing 10' has a reduced-diameter output shaf portion 70 at the output end, coupled to planet gears 72 of a gear train 74 to which the output shaft is also coupled. Thus output can be derived through the shaft or the gear train 74.
Fig. 6 shows a further variant having a hydrostatic unit whose drive is arranged through two planetary gear systems. This is exemplified in an embodiment similar to that of Fig. 1, having a pump but no motor.
Fig. 7 shows another variant of a device, very schematically. A hydrostatic unit 80 includes a motor 82 and a pump 84. They are coupled to respective axial shafts 86,88 (that of the motor passing through that of the pump). Each of the drives 86,88 is fast with a respective one of an opposed pair of frustoconical bevel gears 90,92 (which may have the same or different numbers of teeth. These are engaged by complementary portions of a surrounding annular bevel gear 94. This is coupled to a housing 96, from which an output is derived. Input is fed to a housing 98 of the hydrostatic unit.
The use of bevel gears instead of planetary gears can be applied to other embodiments too. Also generally applicable is the coaxial arrangement of the input and output of the pump (and motor).
Figs. 8 and 9 are sectional views through pumps.
(Motors are similar. ) Fig. 8 illustrates a pump of any of the previously-described embodiments showing a pair of gears 100,102 which might be, for example, the gears 32,34 of the pump shown in Fig. 1 or .Fig 2. There are input and output conduits 104. The oil flow impelled by the gears may be as shown by the arrows. Fig. 9 shows a variant in which the gears are doubled-up, to produce a mechanically balanced assembly.
The invention is not limited to the use of gear pumps. Any type of fluid pump and/or motor may be used, or even other types of hydrostatic coupling device e.g. a torque converter.

Claims

Claims
1. A hydromechanlcal transmission device comprising a first member (12), a second member (14) and h y d r o m e c h a n i c a l c o u p l i n g m e a n s (18, 20, 21, 22, 10, 32,34; 52, 54) for transmitting torque between said first and second members (12,14); said coupling means comprising a housing (10) and a hydrostatic device ( 18, 32, 34;52, 54) located generally within the housing; and wherein the housing (10) is mechanically coupled to the first member (12) so as to be rotatable thereby, and the hydrostatic device (18,32,34) is mechanically coupled to the first member to be driven thereby, and the second member (14) is mechanically coupled to the housing ( 10) so as to be rotatable thereby; the arrangement being such that drive input to the first member (12) is partitioned between the housing (10) and the hydrostatic device ( 18,32,34;52, 54) .
2. A transmission device according to claim 1 wherein the hydrostatic device comprises a fluid pump (32,34) under the control of a pressure relief valve and/or flow control means (16).
3. A transmission device according to claim 1 or 2 wherein the hydrostatic device (18,32,34,52,54) has a first portion coupled to the first member (12) , a second portion coupled to the second member (14), and hydrostatic coupling means between said first and second portions for transmitting torque between them.
4. A transmission device according to claim 3 wherein the hydrostatic coupling means comprises a pump (32,34) and a fluid motor (52,54) the pump being in flow communication with the fluid motor so that the motor is drivable by fluid from the pump.
5. A transmission device according to claim 4 wherein the pump and motor are also operable as a motor and pump respectively.
6. A transmission device according to claim 1 or 2 wherein the hydrostatic device comprises a fluid pump (32,34) having a fluid inlet and a fluid outlet, and the outlet is coupled to the inlet to recycle working fluid through the pump.
7. A transmission device according to any preceding claim wherein the hydrostatic device comprises a casing (18) containing a fluid pump (32,34) operable by a driveshaf (20) ; said first member (12) is coupled to said casing (18) to effect rotation thereof within the housing (10); said driveshaft (20) projects from the casing (18) parallel to but spaced from the axis of rotation thereof and carries a gear (21) which meshes with gear means (22) for rotating the housing (10); and rotation of the driveshaf (20) on its own axis drives the pump (32,34).
8. A transmission device according to claim 7 wherein the housing (10) is coupled by gearing (24,26,28) to the second member ( 14) .
9. A transmission device according to claim 7 or 8 wherein the hydrostatic device includes a fluid motor (52,54) arranged to receive fluid pumped by pump (32,334) and to urge rotation of an internal output shaft (54); and wherein said internal output shaft is coupled by gearing to the second member ( 14) .
10. A transmission device according to any preceding claim wherein the second member (12) is coupled to an annular bevel gear (94) having two angled engagement faces; and there are two inner bevel gears (90,92) located within the annular gear (94) and engaging with respective engagement faces thereof; one of said inner bevel gears (90) being arranged to be driveable by the hydrostatic unit while the other is arranged to be driveable by mechanical transmission from the first member (12).
EP93903241A 1992-02-04 1993-02-04 Continuously-variable hydromechanical parallel-type transmission device Withdrawn EP0624232A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB9202339 1992-02-04
GB929202339A GB9202339D0 (en) 1992-02-04 1992-02-04 Transmission device
PCT/GB1993/000234 WO1993015338A1 (en) 1992-02-04 1993-02-04 Continuously-variable hydromechanical parallel-type transmission device

Publications (1)

Publication Number Publication Date
EP0624232A1 true EP0624232A1 (en) 1994-11-17

Family

ID=10709797

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93903241A Withdrawn EP0624232A1 (en) 1992-02-04 1993-02-04 Continuously-variable hydromechanical parallel-type transmission device

Country Status (5)

Country Link
EP (1) EP0624232A1 (en)
JP (1) JPH07505941A (en)
AU (1) AU3458693A (en)
GB (1) GB9202339D0 (en)
WO (1) WO1993015338A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5569110A (en) * 1991-10-10 1996-10-29 Warren; Walter S. Integrated hydro-mechanical automobile transmission
GB9316143D0 (en) * 1993-08-04 1993-09-22 Wielkopolski Thomas W Rotary drive transmissions
DE102006061116A1 (en) * 2006-12-22 2008-06-26 Audi Ag Power-branching vehicle drive has drive shaft connected mechanically and via hydrostatic pump unit to summation drive, pump unit being connected by sun wheel to shaft and via planet carrier and planet wheel to sun wheel of summation drive
WO2009129666A1 (en) * 2008-04-21 2009-10-29 Feng Zhengmin A automobile hydraulic transmission and differential speed system and a variable volume gear pump

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR994129A (en) * 1944-12-27 1951-11-12 Improvements to motion transmission devices
FR77091E (en) * 1960-02-05 1962-01-12 Renault Variable-ratio hydraulic differential transmission
DE2144063C3 (en) * 1970-09-04 1981-08-13 Antonio Moron Buenos Aires Sardelli Compound transmission
FR2315043A1 (en) * 1975-06-17 1977-01-14 Cerneau Georges Variable speed transmission system - has mechanical and hydraulic system connecting input and output shafts
DE2910184A1 (en) * 1979-03-15 1980-09-25 Gerhard Arnold Steplessly-adjustable drive unit - comprises differential gear train with sun-wheels driven from different sources
US4887487A (en) * 1988-05-03 1989-12-19 Charles D. Johnson Hydro-planetary power division system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9315338A1 *

Also Published As

Publication number Publication date
GB9202339D0 (en) 1992-03-18
WO1993015338A1 (en) 1993-08-05
AU3458693A (en) 1993-09-01
JPH07505941A (en) 1995-06-29

Similar Documents

Publication Publication Date Title
US3986412A (en) Redundant motor reducer drive
US9567999B2 (en) Gear pump or hydraulic gear motor with helical toothing provided with hydraulic system for axial thrust balance
EP0295296B1 (en) Integrated drive generator with common centerline
US4926713A (en) Multiple gear-ratio automatic transmission
US4181041A (en) Dual path, dual range transmission
JPH03539B2 (en)
US4472984A (en) Automatic planetary transmission
US20190113110A1 (en) Infinitely variable power transmission system
US4637275A (en) Torque feedback transmission
US6533695B2 (en) Hydromechanical transmission
EP0624232A1 (en) Continuously-variable hydromechanical parallel-type transmission device
US5545098A (en) Compact steering apparatus
US6338689B1 (en) Hydromechanical transmission
WO2008045368A3 (en) Hydromechanical continuously variable transaxle transmissions
EP2949497B1 (en) A transmission system for a vehicle
US5613919A (en) Zero velocity gear mesh differential
EP0040904B1 (en) Planetary gear assembly and application thereof
US4455891A (en) Power transmission configuration having continuous variable progression of gear reduction ratios
CN112728019A (en) Motor with built-in gear difference planetary gear box
US5624015A (en) Infinitely variable positive gear ratio transmission
CA2250476A1 (en) Hydrostatic coupling comprising a planetary gear pump
RU2110720C1 (en) Stepless closed planetary hydromechanical variable-speed drive
US20080280718A1 (en) Power-splitting hydromechanical continously variable transmission
EP1214534A1 (en) Step-up or reduction gearing
JPS621636A (en) Transmission for vehicle

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19940824

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE

RBV Designated contracting states (corrected)

Designated state(s): DE DK ES FR GB IE IT NL

17Q First examination report despatched

Effective date: 19960814

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19960903