US3750534A - Fluidic regulating apparatus for a reversible hydraulic pump or motor - Google Patents

Fluidic regulating apparatus for a reversible hydraulic pump or motor Download PDF

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Publication number
US3750534A
US3750534A US3750534DA US3750534A US 3750534 A US3750534 A US 3750534A US 3750534D A US3750534D A US 3750534DA US 3750534 A US3750534 A US 3750534A
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signal
fluidic
machine
actual
amplifier
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English (en)
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V Leutner
R Romes
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • 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
    • F16H61/475—Automatic regulation in accordance with output requirements for achieving a target power, e.g. input power or output power
    • 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
    • F04B49/06—Control using electricity
    • 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
    • F04B49/08—Regulating by delivery pressure
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
    • Y10T137/2065—Responsive to condition external of system
    • Y10T137/2071—And causing change or correction of sensed condition

Definitions

  • ABSTRACT A regulating apparatus for a reversible hydraulic machine operating as pump or hydraulic motor in both directions of rotation.
  • the machine can be adjusted to different displacement volumes by fluidic actuating means controlled by an output control signal of an additive control amplifier which compares a first control signal representing the actual displaced volume with a second control signal representing the desired displaced volume.
  • the second control signal is generated in a fluidic control device which includes a fluidic limiting device limiting the second control signal, and being controlled by a first fluidic circuit responsive to the product of the actual and desired volume and fluid pressure of the machine, and by a second fluidic circuit responsive to the highest actual fluid pressure of the machine.
  • the present invention relates to a fluidic regulating apparatus for a reversible hydraulic machine operating as pump or hydraulic motor, and in both directions of rotation.
  • Our above-mentioned U.S. patent application filed Mar. 7, 1972 discloses a regulating apparatus for a hydrostatic pump which is particularly advantageous for a pump operating in open circulation so that regulating and limiting operations can be carried out only when the machine operates as pump in a predetermined direction of rotation, corresponding to a quadrant of a graphical representation of the power output depending on the displaced volume and the pressure of the pump.
  • the object of the invention is obtained by passing the desired value signal obtained by the regulating circuit for the volume adjusting means of the machine, through a bipolar fluidic limiting device to which a limiting signal in the form of a hydraulic value is transmitted, which represents information for the desired value and actual value of the power output and of the pump pressure, and which regulates and limits these values.
  • the regulating apparatus of the invention includes elements of the regulating apparatus disclosed in our prior patent application and uses in the same manner, hydraulic differential pressures, while the introduction of the desired values may be carried-out by means of electro-fluidic transducers.
  • An embodiment of the invention comprises adjusting means for varying the volume of fluid displaced by the machine, actual position measuring means responsive to the position of the adjusting means to generate a first fluidic control signal representing the actual volume displaced by the machine, a fluidic control device for generating a second fluidic control signal representing the desired position of the adjusting means and thereby the volume desired to be displaced by the machine, a fluidic control amplifier receiving the first and second control signals and generating a differential output control signal representing the difference between the actual displaced volume and the volume desired to be displaced by the machine, and actuating means responsive to the output signal to vary the position of the adjusting means until the adjusting means is in the desired position and the machine displaces the desired volume.
  • control device includes a transducer producing the second control signal, a fluidic limiting device receiving the second control signal and transmitting the limited second control signal to the control amplifier, and fluidic control means responsive to the actual value and to the desired value of the power output and of the fluid pressure of the machine to transmit to the fluidic limiting device, a fluidic limiting signal representing the difference between the actual values and the desired values of the power output and fluid pressure of the machine.
  • control means include a fluidic additive limit amplifier transmitting the limiting signal to the limiting device, a first fluidic circuit responsive to the actual and desired volume and fluid pressure of the machine to transmit a first input signal to the additive limit amplifier, and a second fluidic circuit responsive to the actual and desired fluid pressure of the machine to transmit a second input signal to the additive limit amplifier so that the first and second input signals control the limiting signal.
  • the control of the pressures when the machine operates as a hydraulic motor in forward or rearward direction is obtained in accordance with the invention by hydraulic logic means which determine whether the machine operates undersuch conditions. In this event, the adjusting speed of the machine is regulated so tha no excessively high pressure develops.
  • FIG. I is 'a diagrammatic view illustrating a regulating apparatus according to the invention for regulation and limitation of the power output, the pressure, and the displaced volume of an adjustable hydraulic machine, which may operate as a pump or hydraulic motor in either direction of rotation;
  • FIG. 2 is a diagrammatic view illustrating details of a fluidic circuit shown schematically in FIG. 1', and
  • FIG. 3 is a diagram graphically representing the operation of the hydraulic machine in four above-explained operational conditions, represented by hyperbolas in the four quadrants of the diagram shown in FIG. 2.
  • a hydraulic machine 11 which can operate as a pump or hydraulic motor, has
  • adjusting means and may be constructed as an axial piston pump with an adjustable swash plate, as described, for example, in the U. S. Pat. No. 3,489,094.
  • the position of the adjusting means of the hydraulic machine 11 is measured by a position measuring means 12 which transmits a control signal representing the adjusted position and the volume displaced in the adjusted position of the hydraulic machine 11.
  • the control amplifier 13 receives another control signal A from an electro-fluidic transducer, "the signal A passing through a bipolar fluidic limiting device, which may be of the type described in the U. S. Pat. No. 3,516,428.
  • the output control signal of the control amplifier 13 is transmitted to a bipolar fluidic limiting device 14 of the same type and then transmitted to a servo valve and force amplifier 15 for the adjusting means of the hydraulic machine 11.
  • the above-described elements are shown surrounded by a rectangular chain line, and form a unit L for regulating the position of the adjusting means of the hydraulic machine 11 and thereby the pumped volume.
  • the control signal A can be supplied to the regulating unit L mechanically, hydraulically or by means of an electro-fluidic transducer 16 of the type described in the U. S. Pat. No. 3,521,654.
  • the limiting and regulating of the power output and pressure of the hydraulic machine 11 is effected by limiting the control signal A in the bipolar fluidic limiting device 17 which receives a fluidic limiting signal B from the output of an additive limit amplifier 23.
  • the limiting signal B includes information about the desired value and actual value of the power output and pressure of the machine 11.
  • a first fluidic circuit 18 to 22 includes a fluidic multiplier 18, which may be of the type disclosed in the U. S. Pat. No. 3,516,605, which forms the actual value of the power output as a product of the pressure P and the displaced volume 0.
  • the signal representing the product passes through a fluidic rectifier 19, which may be of the type disclosed in the U. S. Pat. No. 3,552,414, which forms the absolute value of the actual power output.
  • This absolute value is supplied as an actual power output signal to an additive power signal amplifier 20, which also receives a desired power output representing signal C from the electrofluidic transducer 31.
  • the additive power signal amplifier forms and amplifies the difference between the absolute value of the actual power output value and the desired power output value.
  • amplifier 20 is shunted by the selective fluidic transmitter 22, which may be of the type described in the U. S. Pat. No. 3,504,689, and preferably includes check valve means, or means for limiting the signal of the power signal amplifier 20.
  • the regulating apparatus of the invention is particularly suitable for hydraulic machines which operate in a closed circulation, in all four quadrants ofa graphical representation of the machine operations, as shown in FIG. 3.
  • the abscissa represents the pressure P of the hydraulic apparatus 11, and the ordinate represents the displaced fluid volume Q.
  • the 6 graphs are hyperbolas representing a constant power output N P.Q.
  • Horizontal lines represent the value Q is constant, and in quadrants I and III, limiting lines representing the pressure P to be substantially constant, are shown.
  • quadrant I and III the hydraulic machine operates as a pump in forward direction in quadrant I and in rearward direction of rotation in quadrant III.
  • quadrants II and IV the machine operates as a hydraulic motor in forward and rearward directions of rotation, respectively.
  • the pressure limitation in quadrants I and III, and the limiting of the speed of pump adjustment in quadrants II and IV, is obtained by a second fluidic circuit 24, shown as a box in FIG. 1, and illustrated in detail in FIG. 2.
  • the hydraulic circuit 24 determines the quadrant and operational condition in which the machine operates. Hydraulic circuit 24 receives, for example from a fluidic transducer 25, the desired value of the pressure P, the electro-fluidic transducer 25 being shown both in FIGS. 1 and 2.
  • the output signals E and E of the fluidic selector circuit 24 corresponds to the difference between the actual pressure P and the desired pressure D.
  • the input signal for the additive limit amplifier 23 is suppressed, but if signal E is positive, during operation of the machine in quadrant I or III, the input signal E is transmitted to the limit amplifier 23.
  • the signal E is supplied to the bi-polar fluidic amplifier 14 of the actuating means l4, 15 of the adjusting means of the hydraulic machine 11.
  • Signal E determines the speed of adjustment of the hydraulic machine 11.
  • the bipolar fluidic limiting device 17 operates in such a manner that its output control signal to the additive control amplifier 13, cannot be greater than the difference between q, b, wherein q is the value of the entire range of the signal from zero to saturation, and b is the value of the limiting signal B. As long as signal B is zero, the amount of displaced fluid volume is not limited.
  • FIG. 2 illustrates in greater detail a selective fluidic circuit 24 connected to the closed circulation of a hydrostatic transmission including the hydraulic machine 11 and a hydraulic motor 27.
  • the hydraulic motor 27 drives an apparatus, for example a winch 27a which drives the hydraulic motor 27 when the load drops due to gravity so that hydraulic motor 27 operates as a pump whereby the hydraulic machine 11 is operated as a hydraulic motor.
  • a pressure selecting valve 28 responds to the highest pressure in the conduits 29, 30, 31, 32 to supply an actual pressure signal through conduit 34 to the additive pressure signal amplifier 33 where the actual pressure signal is compared with the desired pressure signal generated by the electro-fluidic transducer 25. The difference between the pressure signals is amplified, and if negative, blocked by a selective fluidic transmitter 35 of the type described in U. S. Pat. No.
  • the output signal F of the fluidic transmitter 35 is supplied to fluidic logic means 36 which includes slide valves 37 and 38.
  • the logic valve means 36 shifts the fluidic signal F dependent on the operational condition at which the hydraulic machine operates in one of quadrants I to IV, to one of the two outputs 39, 40 whereby the slide valve 37 cancels the selection of the pressure selecting valve which was required for the processing of the signals at the pressure signal amplifier 33.
  • the signal F is supplied to conduit 39, and during operation in quadrants II and IV to conduit 40.
  • the slide valve 38 is controlled by a signal representing the actual value 0 representing the position of the adjusting means of hydraulic machine 1 l, and the associated fluid volume, derived from the regulating unit L,
  • the signal F if supplied to conduit 39, is shifted to conduit 41, and supplied to the additive limit amplifier 23, as shown in FIG. 1. If the signal F is supplied to conduit 40, it is shifted to output 42 and from there to the bipolar fluidic amplifier 14 which controls the actuating means 15 of the adjusting means of the hydraulic machine 11. During operation in the first and third quadrants as shown in FIG. 3, signal F is supplied to output 41. During operation in the second and fourth quadrants, signal F is supplied to output 42.
  • the hyperbolas represent in all four quadrants, the maximum constant value of the power output.
  • quadrants II and IV broken lines 0 indicate a substantially constant value for the pressure P.
  • the fluidic devices used in the apparatus of the invention are well-known, and not an object of the invention.
  • the devices 16, 25, 21 are electro-fiuidic transducers as described in the U. S. Pat. No. 3,521,654; the devices 13, 20, 23, 33 are additive amplifiers of the type disclosed in the U. S. Pat. No. 3,554,206; the devices 14 and 17 are bipolar fluidic limiting devices as described in the U. S. Pat. No. 3,516,428;
  • the measuring device 12 is connected with the swash plate, for example, of an axial piston pump as described in the U. S. Pat. No. 3,489,094;
  • Regulating apparatus for a reversible hydraulic machine comprising adjusting means having a plurality of positions for varying the volume of fluid displaced by said machine; actual position measuring means responsive to the position of said adjusting means to generate a first fluidic control signal representing the actual volume displaced by said machine; a fluidic control device for generating a second fluidic control signal representing the desired position of said adjusting means and thereby the volume desired to be displaced by said machine; a fluidic control amplifier receiving said first and second control signals and generating a differential output-control signal representing the difference between the actual displaced volume and the volume desired to be displaced by said machine; actuating means responsive to said output signal to vary the position of said adjusting means until said adjusting means is in said desired position and said machine displacesthe desired volume; said control device including a transducer producing said second control signal, a fluidic limiting device receiving said second control signal and transmitting the limited second control signal to said control amplifier, and fluidic control means responsive to the actual value and to the desired value of the power output and
  • control means include a fluidic additive limit amplifier transmitting said limiting signal to said limiting device, a first fluidic circuit rep'onsive to the actual and desired volume and fluid pressure of the machine to transmit a first input signal to said additive limit amplifier, and a second fluidic circuit responsive to the actual and desired fluid pressure of the machine to transmit a second input signal to said additive limit amplifier so that said first and second input signals control said limiting signal.
  • said first fluidic circuit includes a fluidic multiplier responsive to the actual displaced volume and to the fluid pressure in the machine to generate an actual power output signal, electro-fluidic transducer means for generating a desired power output signal, and an additive power signal amplifier receiving actual power and desired power signals to generate said first input signal.
  • said first fluidic circuit includes check valve means for shunting said additive power signal amplifier when said first input signal is negative and the desired power output is greater than the actual power output.
  • said second fluidic circuit includes selector valve means responsive to the actual fluid pressure in said machine to transmit an actual pressure signal, electro-fluidic transducer means for transmitting a desired pressure signal, an additive pressure signal amplifier receiving said pressure signals generating a differential pressure signal and a fluidic pressure transmitter for suppressing a negative differential pressure signal and transmitting a positive differential pressure signal to said additive limit amplifier.
  • said second fluidic circuit includes hydraulic logic means connected with conduits of said machine and with said fluidic differential pressure transmitter for determining whether said machine operates as a pump or hydraulic motor and for determining the direction of rotation of said machine whereby the quad rant of a graphical representation of the power output depending on pressure and displaced volume is determined, the first and the third quadrant representing operation of said machine as pump in opposite directions of rotation, respectively, and the second and fourth quadrant representing operation of said machine as hydraulic motor in opposite directions of rotation, respectively, said hydraulic logic means including a first output connected with said limit amplifier for supplying said second input signal when the actual power output is greater than the desired power output, and a second output connected with said actuating means for supplying an actuating signal to said actuating means when the desired power output is greater than the actual power output.
  • Regulating apparatus as claimed in claim 8 wherein said actuating means includes a servo valve; and wherein said fluidic actuating limiting device is an amplifier transmitting a signal to said servo valve.
  • control means include a fluidic additive limit amplifier transmitting said limiting signal to said limiting device, a first fluidic circuit responsive to the actual and desired volume and fluid pressure of the machine to transmit a first input signal to said additive limit amplifier, and a second fluidic circuit responsive to the actual and desired fluid pressure of the machine to transmit a second input signal to said additive limit amplifier so that said first and second input signals control said limiting signal;
  • said first fluidic circuit includes a fluidic multiplier responsive to the actual displaced volume and to the fluid pressure in the machine to generate an actual power output signal, electro-fluidic transducer means for generating a desired power output signal, and an additive power signal amplifier receiving said actual power and desired power signals to generate said first input signals;
  • said second fluidic circuit includes selector valve means responsive to the actual fluid pressure in said machine to transmit an actual pressure signal, electrofluidic transducer means for transmitting a desired pressure signal, an additive pressure signal amplifier receiving said pressure signals generating a differential pressure signal and a fluidic pressure

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Control Of Fluid Gearings (AREA)
  • Reciprocating Pumps (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
US3750534D 1971-04-22 1972-04-20 Fluidic regulating apparatus for a reversible hydraulic pump or motor Expired - Lifetime US3750534A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19712119647 DE2119647A1 (de) 1971-04-22 1971-04-22 Regeleinrichtung für eine Hydropumpe

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US3750534A true US3750534A (en) 1973-08-07

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US3750534D Expired - Lifetime US3750534A (en) 1971-04-22 1972-04-20 Fluidic regulating apparatus for a reversible hydraulic pump or motor

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US (1) US3750534A (enrdf_load_stackoverflow)
CH (1) CH535455A (enrdf_load_stackoverflow)
DE (1) DE2119647A1 (enrdf_load_stackoverflow)
FR (1) FR2136563A6 (enrdf_load_stackoverflow)
GB (1) GB1386472A (enrdf_load_stackoverflow)
IT (1) IT1006535B (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4432703A (en) * 1980-11-26 1984-02-21 Bso Steuerungstechnik Gmbh Industriestrasse Adjusting arrangement for a hydraulic pump with variable discharge flow quantity
US6099273A (en) * 1997-12-02 2000-08-08 Poclain Hydraulics Industrie Hydraulic motor with function selector
EP1751424A4 (en) * 2004-01-14 2012-07-25 Ocean Power Technologies Inc ACTIVE-IMPEDANCE-ADAPTATION SYSTEMS AND METHOD FOR A WAVE-GENERATOR TRANSFORMER
US20250172131A1 (en) * 2022-01-14 2025-05-29 Robert Bosch Gmbh Method with a Hydraulic Pressure Medium Supply Arrangement, and Hydraulic Pressure Medium Supply Arrangement

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4091617A (en) * 1977-05-11 1978-05-30 Eaton Corporation Hydraulic controller
IT1114651B (it) * 1977-05-31 1986-01-27 Eaton Corp Dispositivo di controllo idraulico
EP0105523B1 (en) * 1982-10-05 1988-01-13 Hitachi Construction Machinery Co., Ltd. Automatic neutral point detecting system for hydraulic pump
DE3473909D1 (en) * 1983-01-19 1988-10-13 Hitachi Construction Machinery Failure detection system for hydraulic pump

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3478731A (en) * 1966-08-08 1969-11-18 Honeywell Inc Engine startup sequence control apparatus
US3488948A (en) * 1968-04-29 1970-01-13 Gen Electric Gas turbine engine transient fuel control
US3499599A (en) * 1968-07-25 1970-03-10 Westinghouse Air Brake Co Compressor governor having fluidic devices
US3592083A (en) * 1968-07-13 1971-07-13 Toyoda Machine Works Ltd Automatic transmission control system
US3647322A (en) * 1967-04-12 1972-03-07 Hans Molly Device for controlling quantities which are defined by the product of two measured variables

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3478731A (en) * 1966-08-08 1969-11-18 Honeywell Inc Engine startup sequence control apparatus
US3647322A (en) * 1967-04-12 1972-03-07 Hans Molly Device for controlling quantities which are defined by the product of two measured variables
US3488948A (en) * 1968-04-29 1970-01-13 Gen Electric Gas turbine engine transient fuel control
US3592083A (en) * 1968-07-13 1971-07-13 Toyoda Machine Works Ltd Automatic transmission control system
US3499599A (en) * 1968-07-25 1970-03-10 Westinghouse Air Brake Co Compressor governor having fluidic devices

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4432703A (en) * 1980-11-26 1984-02-21 Bso Steuerungstechnik Gmbh Industriestrasse Adjusting arrangement for a hydraulic pump with variable discharge flow quantity
US6099273A (en) * 1997-12-02 2000-08-08 Poclain Hydraulics Industrie Hydraulic motor with function selector
EP1751424A4 (en) * 2004-01-14 2012-07-25 Ocean Power Technologies Inc ACTIVE-IMPEDANCE-ADAPTATION SYSTEMS AND METHOD FOR A WAVE-GENERATOR TRANSFORMER
US20250172131A1 (en) * 2022-01-14 2025-05-29 Robert Bosch Gmbh Method with a Hydraulic Pressure Medium Supply Arrangement, and Hydraulic Pressure Medium Supply Arrangement

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Publication number Publication date
CH535455A (de) 1973-03-31
GB1386472A (en) 1975-03-05
FR2136563A6 (enrdf_load_stackoverflow) 1972-12-22
DE2119647A1 (de) 1972-11-02
IT1006535B (it) 1976-10-20

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