EP0222764A1 - Manual and automatic governor for a hydrostatic transmission - Google Patents

Manual and automatic governor for a hydrostatic transmission

Info

Publication number
EP0222764A1
EP0222764A1 EP85904097A EP85904097A EP0222764A1 EP 0222764 A1 EP0222764 A1 EP 0222764A1 EP 85904097 A EP85904097 A EP 85904097A EP 85904097 A EP85904097 A EP 85904097A EP 0222764 A1 EP0222764 A1 EP 0222764A1
Authority
EP
European Patent Office
Prior art keywords
governor
pump
cylinder
prime mover
lever
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Withdrawn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
EP85904097A
Other languages
German (de)
French (fr)
Inventor
Elio Vielmi
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.)
Sauer Italiana SpA
Original Assignee
Sauer Italiana SpA
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 Sauer Italiana SpA filed Critical Sauer Italiana SpA
Publication of EP0222764A1 publication Critical patent/EP0222764A1/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Withdrawn legal-status Critical Current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
    • 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
    • F16H61/465—Automatic regulation in accordance with output requirements for achieving a target input speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/002—Hydraulic systems to change the pump delivery
    • 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
    • F16H61/42—Control of exclusively fluid gearing hydrostatic involving adjustment of a pump or motor with adjustable output or capacity
    • F16H61/433—Pump capacity control by fluid pressure control means
    • 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

Definitions

  • the subject of this present invention is a governor which acts on the servocontrol of. a variable-delivery pump, the latter being suitable for a closed circuit and such as to drive the motor at constant revs, whatever the number of revs of the prime mover driving the pump.
  • Said servocontrol normally consists of a distributor which continues to oscillate in its equilibrium position, determined by a manual control lever connected to the distributor by means of gears. These also comprise an elastic means which can istantaneously free said manual control lever from said servocontrol.
  • the proposed governor may be used for any kind of automatic control of the variable-delivery pump, without excluding the possibility of also controlling said pump manually. For example, using the 5. proposed device, the r.p.m. of the drum in truck mixers or other mixing equipment, agitators or the like can be maintained constant, the movement of vehicles in general can be controlled and also the actuating of auxiliary movement in road finishing machines, steamrollers, etc.
  • variable-delivery pump has been controlled only by using very complicated devices, which frequently break down.
  • patent US-A-3,212,263 illustrates a known type of variable-delivery hydraulic pump.
  • French patent application 2,264,991 describes a device 15. suitable for limiting the pressure in an open hydraulic circui .
  • German patent application 1,943,601 only describes the power control, not the governing of the motor speed.
  • German patent application 2,252,557 describes an 20. aut ⁇ natic device suitable for allowing variation in the number of revs of a pump. There is no mention at all of being able to obtain a constant number of revs in a motor.
  • the problem of transmitting motion from a variable-delivery pump to a hydraulic motor has never been completely sa ⁇ tisfactorily solved, especially where the variable-delivery pump is a second use of a variable-revs prime mover.
  • the latter also drives -a first use; for example, in truck mixers it provides for vehicle movement.
  • this first use requires the number of revs of the prime mover to be increased - for example, need to accelerate the engine because the vehicle is driving up a slope or overtaking - the hydraulic
  • the object of this invention is to carry out an 20. automatic control of the variable-delivery pump, while allowing also a manual control of the pump at the same time.
  • the proposed governor allows hydraulic driving of the second use at constant speed, 25. even when the number of revs of the prime mover varies.
  • the aforesaid object has been carried out by providing for the variable-delivery pump servocontrol to be actuated automatic ⁇ ally by means of a single-acting cylinder, the piston of which, subjected to the action of a spring, comprises 5. internally a slider .with free abutting end, which is connected to the servocontrol.
  • a preferred embodiment provides for the piston to be subjected to the action of a set of springs arranged in a pack, which have been calibrated differently one from the other so as to 10. adapt to the pressure curve imparted to the cylinder when being actuated.
  • a specific embodiment provides for the cylinder to be actuated by using the pressure produced by an auxiliary pump which, for example, is fitted directly on the prime mover.
  • Fig. 1 shows the hydraulic diagram of the proposed governor and, purely as an indication, its main mechanical 20. parts;
  • Fig. 2 shows a longitudinal section of the governor
  • Fig. 3 shows a section similar to Fig. 2, but forming part of a second embodiment
  • Fig. 4 is a cross section 4-4 of Fig. 2.
  • the proposed governor has been used in the examples which will be described as a governor for a variable-delivery pump 1 , connected to an motor M which must run at constant speed. This should however in no way be considered as binding.
  • variable-delivery pump 1 is driven by a prime mover MP, which impresses motion to the shaft 1A whereto is also splined the gear pump 1E.
  • the variable-delivery pump now being described, has an oscillating plate 1B pivoted at a fixed central point
  • variable-delivery pumps are fitted with a system for controlling the oscillating plate 1B driven by cylinders 20. 1D.
  • the external manual control 12 consisting of a lever with fulcrum 2A (Figs. 1 and 4)
  • pin 6B integral with said manual control 12 is displaced.
  • lever 21 is displaced. Said lever 21 connected to the connecting rod 23 thus moves pin 7B into a position such as to close the forked spring 2B. At the same time lever 21 moves rod 2C into the neutral position thereby stopping the flow of oil to the servocylinder 1D. As a result
  • control 17 from its neutral position. Through this play of balance between opening and closing of rod 2C of servocontrol 17 the displacement determined by the manual control 12 or the proposed governor is maintained constant.
  • a cylinder 11 which is typically fitted so as to be integral with the servocontrol 17, as can be seen in Figs. 2 and 3.
  • the cylinder 11 is actuated by a lever 2, integral with pin 7B, and having its fulcrum at 2A.
  • cylinder 11 overides manual control 12 because it acts directly on pin 7B and through the latter on connecting rod 23, and thereby on lever 21 and rod 2C.
  • Lever 2 is linked to connecting rod 24 and the latter to the slider 62, said lever not being however integral with the piston 61 in order
  • variable pump 1 available the variable pump 1 , the servocontrol 17 and a pump 1E directly connected to the prime mover MP.
  • the signal obtained before the throttling 2E is directly proportional to the revs of the prime mover MP.
  • the spings 4 arranged in a pack and suitably calibrated, oppose the force exerted by the piston 61 due to the variable pressure signal, allowing said piston 61 to be displaced in proportion to the said pressure.
  • Fig. 2 shows the constructional anbodiment of the proposed governing body 11. As stated above, it is constructed in such a way as to be integral with the servocontrol 17; in particular, it is placed above the latter and connected thereto by lever 2. This governing body may be used for a given direction of rotation of the hydraulic motor M; if the hydraulic motor rotates in the opposite direction, the 5. proposed governor is constructed as can be seen in Fig. 3. However, it is possible to provide a governor which governs for both directions of rotation of the hydraulic motor M.
  • the proposed governor works as follows-
  • selector 9 is positioned as shown in Fig.- 1.
  • this pressure is a function of the speed of the shaft 1A in the prime mover means - displaces the piston 61 as a function

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Control Of Fluid Gearings (AREA)

Abstract

Le régulateur proposé consiste en un cylindre à simple effet (11) dont le piston (61), soumis à une poussée élastique, comporte intérieurement un coulisseau ayant une extrémité libre d'aboutement qui est connectée à la servo-commande de la pompe. Dans un mode préférentiel de réalisation, la poussée élastique est produite par un ensemble de ressorts (4) disposés sous la forme d'un paquet et qui sont calibrés de manière à s'adapter à la courbe de pression arrivant au cylindre (11), en cours d'actionnement. On prévoit également l'actionnement du cylindre (11) en utilisant la pression produite par une pompe auxiliaire (1E) qui, par exemple, est montée directement sur le moteur principal.The proposed regulator consists of a single-acting cylinder (11) whose piston (61), subjected to an elastic thrust, internally comprises a slide having a free abutting end which is connected to the servo control of the pump. In a preferred embodiment, the elastic thrust is produced by a set of springs (4) arranged in the form of a package and which are calibrated so as to adapt to the pressure curve arriving at the cylinder (11), during operation. It is also provided for the actuation of the cylinder (11) using the pressure produced by an auxiliary pump (1E) which, for example, is mounted directly on the main engine.

Description

tomatic governor for a hydrostatic
The subject of this present invention is a governor which acts on the servocontrol of. a variable-delivery pump, the latter being suitable for a closed circuit and such as to drive the motor at constant revs, whatever the number of revs of the prime mover driving the pump. Said servocontrol normally consists of a distributor which continues to oscillate in its equilibrium position, determined by a manual control lever connected to the distributor by means of gears. These also comprise an elastic means which can istantaneously free said manual control lever from said servocontrol. The proposed governor may be used for any kind of automatic control of the variable-delivery pump, without excluding the possibility of also controlling said pump manually. For example, using the 5. proposed device, the r.p.m. of the drum in truck mixers or other mixing equipment, agitators or the like can be maintained constant, the movement of vehicles in general can be controlled and also the actuating of auxiliary movement in road finishing machines, steamrollers, etc.
10. Until now a variable-delivery pump has been controlled only by using very complicated devices, which frequently break down.
*»
In particular patent US-A-3,212,263 illustrates a known type of variable-delivery hydraulic pump.
French patent application 2,264,991 describes a device 15. suitable for limiting the pressure in an open hydraulic circui .
German patent application 1,943,601 only describes the power control, not the governing of the motor speed.
Lastly, German patent application 2,252,557 describes an 20. autαnatic device suitable for allowing variation in the number of revs of a pump. There is no mention at all of being able to obtain a constant number of revs in a motor. The problem of transmitting motion from a variable-delivery pump to a hydraulic motor has never been completely sa¬ tisfactorily solved, especially where the variable-delivery pump is a second use of a variable-revs prime mover. Usually
5. the latter also drives -a first use; for example, in truck mixers it provides for vehicle movement. When this first use requires the number of revs of the prime mover to be increased - for example, need to accelerate the engine because the vehicle is driving up a slope or overtaking - the hydraulic
10. pump sends a greater quantity of oil to the hydraulic motor. Consequently this motor runs faster, absorbing a greater amount of power. This is an utmost undesired effect, either because the second use must noπnally be driven at a predetermined speed independent frαn that of the prime mover,
1 . or because this second use wastefully absorbs a greater share of power, required instead by the first use, which has caused the number of revs of the prime mover to vary for this precise reason.
Therefore, the object of this invention is to carry out an 20. automatic control of the variable-delivery pump, while allowing also a manual control of the pump at the same time.
In particular, in a transmission unit comprising at least two uses driven by a single prime mover, the proposed governor allows hydraulic driving of the second use at constant speed, 25. even when the number of revs of the prime mover varies. The aforesaid object has been carried out by providing for the variable-delivery pump servocontrol to be actuated automatic¬ ally by means of a single-acting cylinder, the piston of which, subjected to the action of a spring, comprises 5. internally a slider .with free abutting end, which is connected to the servocontrol.
A preferred embodiment provides for the piston to be subjected to the action of a set of springs arranged in a pack, which have been calibrated differently one from the other so as to 10. adapt to the pressure curve imparted to the cylinder when being actuated.
A specific embodiment provides for the cylinder to be actuated by using the pressure produced by an auxiliary pump which, for example, is fitted directly on the prime mover.
15. This invention will now be illustrated more clearly on the basis of two non-binding exemplary embodiments shown in the accompanying drawings, in which:
Fig. 1 shows the hydraulic diagram of the proposed governor and, purely as an indication, its main mechanical 20. parts;
Fig. 2 shows a longitudinal section of the governor;
Fig. 3 shows a section similar to Fig. 2, but forming part of a second embodiment; and
Fig. 4 is a cross section 4-4 of Fig. 2. The proposed governor has been used in the examples which will be described as a governor for a variable-delivery pump 1 , connected to an motor M which must run at constant speed. This should however in no way be considered as binding.
5 Referring to Figs. 1 and 4, it will be seen that the varia¬ ble-delivery pump 1 is driven by a prime mover MP, which impresses motion to the shaft 1A whereto is also splined the gear pump 1E. The variable-delivery pump, now being described, has an oscillating plate 1B pivoted at a fixed central point
10. 1C. Furthermore, two ends of the oscillating plate 1B are connected to servocylinders indicated by 1D. After the oscillating plate 1B has been positioned, the pump delivery is directly proportional to the speed of rotation of the prime mover MP; this speed is indicated schematically by arrow E. If
15. the number of revs E of the prime mover MP varies it is evident that, no governor being present, the speed of rotation of the hydraulic motor M will also vary.
As is known, variable-delivery pumps are fitted with a system for controlling the oscillating plate 1B driven by cylinders 20. 1D. By inclining the external manual control 12, consisting of a lever with fulcrum 2A (Figs. 1 and 4), pin 6B integral with said manual control 12 is displaced.
Because of the resistance applied by the servocylinders 1D, connected to the oscillating plate 1B, displacement of pin 6B
25. simply causes the opening of spring 2B, made up of a fork pivoted at fulcrum 2A and having two arms wherein pins 6B and 7B are contained.
The elastic action of the spring 2B on pin 7B is transmitted by the connecting rod 23, pivoted on the latter, to the lever 5. 21 which in this case will move as if its fulcrum were at end 4B due to the aforesaid resistance from the servo-cylinders 1D.
The inclination given to the external manual control 12 is thus transmitted by the described gears to rod 2C of the 10. servocontrol 17. When rod 2C inside casing 17A is displaced from its neutral position, it sends oil to one of the servocylinders 1D, which inclines the oscillating plate 1B to the angle set .using the manual control lever 12.
By means of the connecting rod 20 pivoted on an extension of
15. the oscillating plate 1B, lever 21 is displaced. Said lever 21 connected to the connecting rod 23 thus moves pin 7B into a position such as to close the forked spring 2B. At the same time lever 21 moves rod 2C into the neutral position thereby stopping the flow of oil to the servocylinder 1D. As a result
20. of oil oozing into the cylinder 1D, which is being actuated, and also due to the counteraction of the spring of the other cylinder 1D, opposed to the pressurized one being actuated, a displacement of the linkages is obtained equal to that given using the manual control 12, thus moving rod 2C of servo-
25. control 17 from its neutral position. Through this play of balance between opening and closing of rod 2C of servocontrol 17 the displacement determined by the manual control 12 or the proposed governor is maintained constant.
5. In order to achieve the latter a cylinder 11 has been provided, which is typically fitted so as to be integral with the servocontrol 17, as can be seen in Figs. 2 and 3. The cylinder 11 is actuated by a lever 2, integral with pin 7B, and having its fulcrum at 2A. In this arrangement, when
10. inserted, cylinder 11 overides manual control 12 because it acts directly on pin 7B and through the latter on connecting rod 23, and thereby on lever 21 and rod 2C. Lever 2 is linked to connecting rod 24 and the latter to the slider 62, said lever not being however integral with the piston 61 in order
15. to also permit movement in the linkages of the complex system of the servocontrol 17, which maintains constant the fixed displacement of the pump 1.
With the governor disconnected the lever 12 is free for manual control of displacement, since said lever 12 is not connected 20. directly to piston 61 by connecting rod 24 but to the slider 62, which moves freely in the governor cylinder until it strikes against the piston 61.
In order to have the hydraulic motor M run at constant revs with the prime mover at varying revs, it is necessary to have
2 . available the variable pump 1 , the servocontrol 17 and a pump 1E directly connected to the prime mover MP.
Pump 1E, indicated in Fig. 1, is fitted with a maximum pressure valve 3E.
In order to prevent intervention by said valve at a setting 5- fixed below the required signal, the throttling 2E has been applied, which diverts the oil flow to the selector 9 for connecting or disconnecting the governing body 11.
The signal obtained before the throttling 2E is directly proportional to the revs of the prime mover MP.
1°* Inside the cylinder chamber 11B of the governor 11 said signal actuates the piston 61 and then the slider 62, if the latter's free abutting end 62A is touching the piston head 61A; subsequently the servocontrol 17 of the variable-delivery pump is actuated by connecting rod 24, lever 2, connecting rods 23
15. and 20 and lever 21.
The spings 4, arranged in a pack and suitably calibrated, oppose the force exerted by the piston 61 due to the variable pressure signal, allowing said piston 61 to be displaced in proportion to the said pressure.
20. Fig. 2 shows the constructional anbodiment of the proposed governing body 11. As stated above, it is constructed in such a way as to be integral with the servocontrol 17; in particular, it is placed above the latter and connected thereto by lever 2. This governing body may be used for a given direction of rotation of the hydraulic motor M; if the hydraulic motor rotates in the opposite direction, the 5. proposed governor is constructed as can be seen in Fig. 3. However, it is possible to provide a governor which governs for both directions of rotation of the hydraulic motor M.
The proposed governor works as follows-
After having set lever 12 so as to supply the required amount
10. of oil, thereby determining the desired speed of the hydraulic motor M, selector 9 is positioned as shown in Fig.- 1. As a result the pressure produced by the fixed delivery pump 1E - this pressure is a function of the speed of the shaft 1A in the prime mover means - displaces the piston 61 as a function
15. of the oil pressure inside the body 11B of cylinder 11 , said piston being opposed by the different force of the springs 4 arranged in a pack. When the slider 62 is free to run again, the piston 61 actuates lever 2 by means of connecting rod 24. As it is integral with pin 7B, said lever moves the linkages
20. for controlling displacement, causing it to decrease and ii ntaining constant the number of revs of the hydraulic motor M, independently of the torque absorbed by said hydraulic motor. It will be seen in particular that, according to Fig. 2, the springs are compressed when the lever 2 is displaced
25. from right to left, whereas according to Fig. 3 the springs are cαπpressed when the lever 2 is displaced in the opposite direction.

Claims

C L A I M S
1. A manual and automatic governor for a hydraulic motor which is actuated by a variable delivery pump (1 ) in a closed circuit, said pump being driven by a prime mover Injrning at a variable number of revs, said governor comprising
-**• a servo-control (17) consisting of a distributor positioned by a manual control lever (12) connected to said distributor by gears, which also include an elastic means (2A) for instantan¬ eously freeing said manual control lever (12) from said servocontrol (17); characterized in that provision is made to
10. automatically actuate the variable delivery pump (1 ) servo¬ control (17) by means of a single-acting cylinder (11), the piston (61 ) of which, subjected to the action of the spring (4), comprises internally a slider (62) with free abutting end (62A) which is connected to the servocontrol (17).
15.
2. A governor according to claim 1, characterized in that the piston (61 ) is subjected to the action of a set of springs (4), arranged in a pack, which are calibrated differently from one another so as to adapt to the pressure curve arriving at the cylinder (11 ) when actuated.
3. A governor according to claim 1 , characterized in 5. that the cylinder (11 ) is driven using the pressure produced by an auxiliary pump (1E) which, for example, is fitted directly on the prime mover (MP), which also drives the variable delivery pump (1 ).
EP85904097A 1984-07-30 1985-07-15 Manual and automatic governor for a hydrostatic transmission Withdrawn EP0222764A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT22124/84A IT1174619B (en) 1984-07-30 1984-07-30 REGULATOR THAT ALLOWS TO KEEP THE ROTATION SPEED OF A HYDRAULIC MOTOR OPERATED BY A VARIABLE FLOW PUMP CONSTANTLY, EVEN WHEN THE NUMBER OF PRIMARY ENGINE REVOLUTIONS VARY
IT2212484 1984-07-30

Publications (1)

Publication Number Publication Date
EP0222764A1 true EP0222764A1 (en) 1987-05-27

Family

ID=11191850

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85904097A Withdrawn EP0222764A1 (en) 1984-07-30 1985-07-15 Manual and automatic governor for a hydrostatic transmission

Country Status (5)

Country Link
EP (1) EP0222764A1 (en)
JP (1) JPS61502832A (en)
AU (1) AU4773185A (en)
IT (1) IT1174619B (en)
WO (1) WO1986000963A1 (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007047195A1 (en) * 2007-10-02 2009-04-09 Zf Friedrichshafen Ag Adjustment of the stroke volume of hydraulic piston machines
KR101514475B1 (en) 2007-10-02 2015-04-22 젯트에프 프리드리히스하펜 아게 Variable transmission device for a vehicle
WO2009047034A1 (en) 2007-10-02 2009-04-16 Zf Friedrichshafen Ag Power-branched transmission
ATE534849T1 (en) 2007-10-02 2011-12-15 Zahnradfabrik Friedrichshafen TRANSMISSION DEVICE FOR A VEHICLE HAVING A VARIATOR
DE102007047194A1 (en) 2007-10-02 2009-04-09 Zf Friedrichshafen Ag Power split transmission
ATE533970T1 (en) 2007-10-02 2011-12-15 Zahnradfabrik Friedrichshafen TRANSMISSION DEVICE WITH A VARIATOR
EP2381135B1 (en) 2007-10-02 2012-05-30 ZF Friedrichshafen AG Hydromechanical power split drive
WO2009047037A1 (en) 2007-10-02 2009-04-16 Zf Friedrichshafen Ag Hydrostatic-mechanical power split transmission
ATE528548T1 (en) 2007-10-02 2011-10-15 Zahnradfabrik Friedrichshafen TRANSMISSION DEVICE FOR A VEHICLE
US8752374B2 (en) 2007-10-02 2014-06-17 Zf Friedrichshafen Ag Device for adjusting the stroke volume of hydraulic piston machines

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Publication number Priority date Publication date Assignee Title
DE1160734B (en) * 1958-09-18 1964-01-02 Kaemper Motoren G M B H Control unit for axial piston pumps
US3212263A (en) * 1964-04-24 1965-10-19 Sundstrand Corp Hydrostatic transmission
DE1500400B1 (en) * 1965-07-20 1970-12-03 Linde Ag Hydrostatic gear for driving the mixing drum of a transport mixer
DE1943601C3 (en) * 1969-08-27 1975-11-06 Joseph Lucas (Industries) Ltd., Birmingham (Grossbritannien) Control device for an axial piston pump
BE790782A (en) * 1971-11-01 1973-02-15 Massey Ferguson Services Nv SPEED CONTROL DEVICE FOR HYDROSTATIC TRANSMISSION
DD110684A1 (en) * 1974-03-20 1975-01-05
GB1588885A (en) * 1977-10-26 1981-04-29 Zahnradfabrik Friedrichshafen Hydrostatic power transmission in series with a changespeed gear

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8600963A1 *

Also Published As

Publication number Publication date
JPS61502832A (en) 1986-12-04
IT8422124A0 (en) 1984-07-30
AU4773185A (en) 1986-02-25
WO1986000963A1 (en) 1986-02-13
IT1174619B (en) 1987-07-01

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