WO1996009482A1 - Transmissions a gammes multiples - Google Patents

Transmissions a gammes multiples Download PDF

Info

Publication number
WO1996009482A1
WO1996009482A1 PCT/GB1995/002207 GB9502207W WO9609482A1 WO 1996009482 A1 WO1996009482 A1 WO 1996009482A1 GB 9502207 W GB9502207 W GB 9502207W WO 9609482 A1 WO9609482 A1 WO 9609482A1
Authority
WO
WIPO (PCT)
Prior art keywords
clutch
transmission
speed
range
pump
Prior art date
Application number
PCT/GB1995/002207
Other languages
English (en)
Inventor
David Richard Armour
Original Assignee
J. C. Bamford Excavators Limited
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 J. C. Bamford Excavators Limited filed Critical J. C. Bamford Excavators Limited
Publication of WO1996009482A1 publication Critical patent/WO1996009482A1/fr

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
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/04—Smoothing ratio shift
    • 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
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/38—Control of exclusively fluid gearing
    • F16H61/40—Control of exclusively fluid gearing hydrostatic
    • 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
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/38—Control of exclusively fluid gearing
    • F16H61/40—Control of exclusively fluid gearing hydrostatic
    • F16H61/46—Automatic regulation in accordance with output requirements
    • F16H61/462—Automatic regulation in accordance with output requirements for achieving a target speed ratio
    • 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
    • F16H37/0833—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 with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths
    • F16H37/084—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 with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths at least one power path being a continuously variable transmission, i.e. CVT
    • F16H2037/088—Power split variators with summing differentials, with the input of the CVT connected or connectable to the input shaft

Definitions

  • This invention relates to a multi-range transmission, hereinafter referred to as being of the kind specified, having a first output element connectable to a first clutch in a torque transmitting path of a first range and a second output element connectable by a second clutch in a torque transmitting path of a second range and in which the speed of the first and second elements vary inversely so as to rotate synchronously at a range change condition.
  • An object of the invention is to provide a multi-range transmission of the kind specified in which the abovementioned problems are overcome or reduced.
  • a multi-range transmission of the kind specified comprising synchronicity sensing means to sense when said elements are rotating synchronously, first clutch operating means to engage the second clutch when the first and second elements are synchronous, torque adjustment means to adjust the torque transmitted by the second clutch to a predetermined value relative to the torque transmitted by the first clutch at synchronicity or at a predetermined speed difference prior to synchronicity and second clutch operating means to disengage the first clutch when the torque transmitted by the second clutch equals said predetermined value.
  • the transmission may comprise a power split transmission comprising a summing gear set having first and second input elements and said first and second output elements, an input member connected to said input elements through a speed varying means to vary the speed of rotation of the first and second input elements to cause said inverse variation of the speed of rotation of said output elements.
  • the input member may be mechanically connected to said first input element and may be connected to the second input element through said speed varying means.
  • the speed varying means may comprise a hydrostatic transmission.
  • the hydrostatic transmission may comprise a hydraulic pump device driven mechanically by said input member and a hydraulic motor drive hydraulically by said pump and having an output element drivingly connected to said second input element.
  • At least one of the hydraulic motor and pump may be of variable displacement.
  • the pump is of variable displacement whilst the motor is of constant displacement.
  • the motor and the pump may be connected in a hydraulic circuit having a first branch extending between a first port of the pump and a first port of the motor and a second branch extending between a second port of the motor and a second port of the pump.
  • the volume and the direction of flow depend upon the setting of the variable displacement pump.
  • a "positive" swash plate angle may cause flow along the first branch A from the pump to the motor and return flow from the motor to the pump along the second branch B whereas negative swash plate angle may cause flow of fluid from the pump to the motor along the second branch and from the motor to the pump along the first branch.
  • the pressure obtaining in the first branch hereinafter referred to as P a may vary compared with the pressure P b obtaining in the second branch, hereinafter referred to as P b and the pressure difference is dependent upon the magnitude of the torque output of the motor. For example, with positive swash plate angle and flow in branch A from pump to motor then P a is greater than P b whereas with negative swash plate angle and flow from the pump to the motor via branch B, P b is greater than P a .
  • Said torque adjustment means may therefore comprise means to sense a pressure difference between the pressure obtaining in the two branches of the hydraulic circuit at synchronicity or at a predetermined speed difference prior to synchronicity, means to determine a target pressure difference for drive transmission by said second clutch, and means to adjust the displacement of the pump to achieve said target pressure difference.
  • Means may be provided to maintain the value of the pressure difference at that sensed or at a predetermined relationship to that sensed whilst determining the target pressure difference and whilst engaging the second clutch.
  • Means may be provided to ascertain that the second clutch is engaged prior to performing the step of adjusting the displacement of the pump to achieve said target pressure difference.
  • Means may be provided to determine that said target pressure difference has been achieved prior to permitting release of the first clutch.
  • Means may be provided to determine that the first clutch has been released before permitting operation in the new range.
  • the control means may comprise a microprocessor.
  • FIGURE 1 is a diagrammatic illustration of a transmission ⁇ embodying the invention
  • FIGURE 2 is another illustration of a transmission of Figure 1 but showing the gear ratios
  • FIGURE 3 is a diagrammatic illustration showing the pressure difference between branches of the hydraulic circuit shown in Figures 1 and 2 with output torque of the transmission;
  • FIGURE 4 is a flow diagram of a programme executed by a microprocessor during use of the transmission embodying the invention.
  • the transmission of Figures 1 and 2 incorporates a four branch differential gear 10 which comprises a planet carrier 30 which carries three first planet gears 31 and three second planet gears 32.
  • the first planet gears are of constant diameter and mesh with a first sun gear 36 and with a portion of the second planet gears 32.
  • a longitudinally adjacent portion of the second planet gears 32 meshes with a second sun gear 39.
  • the second planet gears 32 are also in mesh with an annulus 40.
  • the carrier 30 acts as a first shaft of the controllable four branch differential gear 10, whilst the annulus 40 acts as a second shaft, the first sun gear 36 acts as a third shaft, and the second sun gear 39 acts as a fourth shaft.
  • the annulus 40 is connected to a hollow shaft 60 whilst the second sun gear 39 is carried by a further hollow shaft 61.
  • the first sun gear 36 is connected to a shaft 37 whilst the carrier 30 is connected to a hollow shaft 29.
  • the carrier 30 is provided with a peripheral gear 55.
  • the inner hollow shaft 61 is provided with a gear 62 which meshes with a second gear 63 of a range change gear set 64.
  • the gear 63 is connectable by a fourth, or first output/range change, clutch 65 to a lay shaft 66 to which is fixed a first lay shaft gear 67 which meshes with a gear 68 fixed to the hollow shaft 69 which is mounted to rotate co-axially with the shaft 61.
  • the shaft 69 is connected by gear 82 and gears 80 and 81 to forward and reverse output members 12F and 12R.
  • the outer tubular shaft 60 connected to the annulus 40 is connectable by a fifth or second output clutch 71 to the tubular shaft 69 whilst the inner shaft 61 is connectable by a sixth, or third output, clutch 70 to a tubular shaft 69.
  • the engine 11 is connected by an input member 13 to the transmission.
  • the input member 13 is connected to an input gear 72 with meshes with a first input gear 73 and with a second input gear 74.
  • the second gear 74 meshes with a gear 76 which drives an input element 77 of a variable speed hydrostatic transmission 20.
  • the hydrostatic transmission 20 may be of any suitable variable displacement type and comprises, in this example, a variable displacement swash plate pump and a swash plate motor. However, either or both of which may be of adjustable displacement so as to vary the speed and direction of rotation of the output element 22 of the motor relative to that of the input element 18 of the pump. If desired, instead of a hydrostatic transmission any other suitable (continuously) variable speed transmission may be used.
  • the shaft 37 connected to the first sun gear 36 is connected to a first gear 78 which meshes with a second gear 79 which is driven by a third gear 78 connected to the output element 22 of the transmission 20.
  • the second gear 79 is connected by a first, or hydrostatic, clutch H to an intermediate gear 75 which meshes with the gear 55 of the carrier 30.
  • the carrier 30 is connectable by a second, or forward, clutch F to a hollow shaft connected to the first input idler 73 whilst the second input idler gear 74 is connectable by a third or reverse clutch R to an intermediate gear 75.
  • the engine 11 drives the input element 77 of the hydrostatic transmission 20 via gears 72, 74 and 76. No drive is communicated to the four branch differential directly from the engine since the clutches F and R are disengaged.
  • the output element 22 of the hydrostatic transmission is connected by gears 78, 79 and 78 to the first sun gear 36 and by the gears 78, 79, clutch H and gears 75 and 55 to the carrier 30 and thus the carrier and the sun gear are rotated in the same direction at the same speed. Initially, since the swash plate angle is zero, no movement of the output element 22 takes place and the vehicle remains stationary.
  • the swash plate angle is increased in a forward drive direction to cause the output element 22 to rotate in the forward direction, thus rotating the first sun gear 36 and carrier 55 in the same direction and at the same speed so that the differential 10 rotates as a "locked" unit and hence the two output shafts 60, 67 also rotate at the same speed as each other and at the same speed as the two input shafts 37, 29.
  • the gear set 10 gears are arranged to be driven at the speed of rotation of the input member 13, but in the reverse direction thereto, so that the second clutch F may be engaged and then the first clutch H allowed to become disengaged in a similar manner to previously described embodiments.
  • the swash plate angle may be reduced and hence the speed of rotation of the sun gear 36 decreased whilst the speed of rotation of the carrier 30 is maintained at the same "engine” speed and as a result the speed of rotation of the sun gear 39 increases and this increase in speed of rotation is transmitted to the output members 12F and 12R through the first output/lay shaft clutch 65 as in purely hydrostatic drive.
  • the hereinbefore described transmission therefore provides forward or reverse drive up to a hydrostatic range and three compound ranges thus providing maximum torque at zero vehicle speed as the vehicle starts to move in either forward or reverse.
  • the highest range in reverse may be omitted when it is not required to drive a vehicle in reverse in the speed range which would be provided by the highest speed range. This is provided simply by inhibiting engagement of third clutch 70 and preventing disengagement of clutch 71 when clutch 8R is engaged, in the control means of the transmission.
  • Figure 2 shows the number of teeth provided on the various gears of the embodiment shown in Figure 1.
  • the slowest speed of annulus 40 is 0.448A rpm where Rpm is the speed of rotation of the input member 13, whilst the speed of rotation of the second sun gear 39 is then at its fastest, namely 2.234A.
  • the ratio of the two speeds is 4.99.
  • a pressure transducer P is provided in a first branch A of a hydraulic circuit between the pump 19 and the motor 21 and a second transducer P 2 in the branch B of the circuit.
  • the transducers Pj and P 2 provide a signal dependent upon pressure in the respective branch, on lines L,, L- 2 to a central processing unit CPU.
  • the engine 11 and the output element 22 of the motor 21 are provided with a respective speed sensor S ⁇ , S 2 which provides signals, indicative of the speed of rotation of their associated element, on lines SL, and SL 2 respectively to the CPU. Because the components on opposite sides of the clutches which provide range change are rotated in a fixed and known relationship to the engine and the motor their speed of rotation is calculated by the C.P.U.
  • the CPU is connected by line P to a swash plate control mechanism 90.
  • the CPU is also connected by lines C, - C 6 to solenoid operated valves of hydraulic means M for engaging the clutches.
  • each clutch is engaged by a hydraulic ram unit which, when energised, moves the clutch into engagement against a spring bias and, when de-energised permits the clutch to be disengaged by the spring bias.
  • the CPU determines the pressure difference P a - P b as detected by the sensors P, or P 2 in the branches A and B of the circuit.
  • the CPU then sends a signal to the swash plate control 90 so as to maintain this pressure difference for the time being.
  • the CPU determines, for example either by calculation or by using a look-up table, a target pressure to be attained during initial operation in the new range.
  • the CPU then sends a signal to the swash plate control 90 to cause the swash plate angle to be adjusted to bring the pressure difference to the target pressure or with a predetermined value thereof.
  • the CPU then checks whether or not the target pressure range has been achieved, and, if it has, it sends a signal to the appropriate line C, - C 6 to the clutch of the old range to cause it to be released. Since at this stage the torque is adjusted so as to be equal to the target pressure range for the new range, the old clutch will be unloaded or substantially unloaded and therefore can move out of engagement under spring pressure.
  • the CPU then checks that the clutch has been disengaged and, assuming it has, normal operation of the transmission is permitted.
  • the target pressure in the present example, is determined empirically on the basis of tests but it may be calculated on the basis of the pressure difference and gear ratio and the ratio of the variable speed transmission.
  • Figure 3 illustrates the variation in pressure difference whilst Figure 4 shows a flow diagram of the programme executed by the CPU which, preferably, is a microprocessor controlled device of known type.
  • the CPU may cause the swash ramp to be slowed as synchronicity of the respective pair of elements is approached.

Landscapes

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

Abstract

Transmission à gammes multiples possédant un premier élément de sortie pouvant être raccordé à un premier embrayage dans une voie de transmission de couple d'une première gamme, ainsi qu'un second élément de sortie pouvant être raccordé par un second embrayage dans une voie de transmission de couple d'une seconde gamme, la vitesse des premier et second éléments variant en proportion inverse de manière à tourner de manière synchrone lors d'un changement de gamme; cette transmission comporte également des moyens capteurs de synchronisme destinés à détecter le moment où lesdits éléments tournent de manière synchrone, un mécanisme d'actionnement du premier embrayage destiné à enclencher le second embrayage lorsque les premier et second éléments sont synchrones, des moyens de réglage de couple destinés à régler le couple transmis par le second embrayage au niveau d'une valeur prédéterminée par rapport au couple transmis par le premier embrayage, lors de l'atteinte du synchronisme ou d'une différence de vitesse prédéterminée précédant ce synchronisme, ainsi qu'un mécanisme d'actionnement du second embrayage destiné à débrayer le premier embrayage lorsque le couple transmis par le second embrayage est égal à la valeur prédéterminée.
PCT/GB1995/002207 1994-09-21 1995-09-18 Transmissions a gammes multiples WO1996009482A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9418986A GB9418986D0 (en) 1994-09-21 1994-09-21 Multi-range transmissions
GB9418986.7 1994-09-21

Publications (1)

Publication Number Publication Date
WO1996009482A1 true WO1996009482A1 (fr) 1996-03-28

Family

ID=10761654

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1995/002207 WO1996009482A1 (fr) 1994-09-21 1995-09-18 Transmissions a gammes multiples

Country Status (2)

Country Link
GB (1) GB9418986D0 (fr)
WO (1) WO1996009482A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1128093A3 (fr) * 2000-02-22 2002-01-30 Same Deutz-Fahr S.P.A. Transmission hydromécanique ayant une transmission à rapport continu

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4068543A (en) * 1975-05-30 1978-01-17 Toyota Jidosha Kogyo Kabushiki Kaisha Hydraulic transmission control device
EP0234136A1 (fr) * 1986-02-24 1987-09-02 Shimadzu Corporation Transmission hydromécanique
EP0301590A2 (fr) * 1987-07-31 1989-02-01 Shimadzu Corporation Variateur continu de vitesse
EP0444472A2 (fr) * 1990-02-13 1991-09-04 Michael Meyerle Dispositif de commande, particulièrement pour véhicule à moteur
WO1994008156A2 (fr) * 1992-10-06 1994-04-14 J. C. Bamford Excavators Limited Systeme de transmission variable en continu a division de puissance

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4068543A (en) * 1975-05-30 1978-01-17 Toyota Jidosha Kogyo Kabushiki Kaisha Hydraulic transmission control device
EP0234136A1 (fr) * 1986-02-24 1987-09-02 Shimadzu Corporation Transmission hydromécanique
EP0301590A2 (fr) * 1987-07-31 1989-02-01 Shimadzu Corporation Variateur continu de vitesse
EP0444472A2 (fr) * 1990-02-13 1991-09-04 Michael Meyerle Dispositif de commande, particulièrement pour véhicule à moteur
WO1994008156A2 (fr) * 1992-10-06 1994-04-14 J. C. Bamford Excavators Limited Systeme de transmission variable en continu a division de puissance

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1128093A3 (fr) * 2000-02-22 2002-01-30 Same Deutz-Fahr S.P.A. Transmission hydromécanique ayant une transmission à rapport continu
US6450912B2 (en) 2000-02-22 2002-09-17 Same Deutz-Fahr S.P.A. Hydromechanical transmission having a continuously variable transmission ratio

Also Published As

Publication number Publication date
GB9418986D0 (en) 1994-11-09

Similar Documents

Publication Publication Date Title
US4776233A (en) Hydromechanical transmission and hydromechanical speed-change mechanism
US5088352A (en) System for controlling hydraulic fluid pressure for V-belt type automatic transmission
US4627312A (en) Automatic transmission
EP0417283B1 (fr) Transmission mecanique-hydraulique intermediaire et procede de commande de cette transmission
US5168778A (en) CVT downshift control strategy to minimize slip at the drive pulley
EP0071801A1 (fr) Transmission à courroie en "V" à vitesse continûment variable pour véhicule
US5788600A (en) Continuously variable transmission
US4775938A (en) System and method for controlling a power transmission of a vehicle
US5671137A (en) Response control system for hydrostatic-mechanical transmissions
EP2118523B1 (fr) Procede pour controler deux unites hydrostatiques a deplacement variable dans une transmission hydromecanique variable a l'infini
US4246806A (en) Multi-mode hydromechanical transmission shift system
EP0438486B1 (fr) Transmission variable en continu
JPS63167171A (ja) 油圧式無段変速機
US5813933A (en) Continuously variable transmission with bias springs on the drive and driven pulleys for setting a predetermined speed ratio when the cut is in neutral
JP3500826B2 (ja) 変速比無限大無段変速機の変速制御装置
EP0632217B1 (fr) Transmission de puissance et système de commande
EP0467410A2 (fr) Ensemble valve de commande d'une transmission à rouleaux de traction
WO1996009482A1 (fr) Transmissions a gammes multiples
JPS61103049A (ja) 車両用無段変速機の制御装置
US5157993A (en) Hybrid continuously variable transmission with electronically controlled clutch
EP1092887B1 (fr) Système de commande d' un embrayage de démarrage pour transmission à variation continue
EP0341818B1 (fr) Dispositif pour détecter le freinage du moteur
US4304155A (en) Power shift transmissions
EP1092895A2 (fr) Transmission continue de vitesse du type torique
JP2699328B2 (ja) 車両用ベルト式無段変速機の変速比制御方法

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA GB US

AL Designated countries for regional patents

Kind code of ref document: A1

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

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA