SU736884A3 - Volumetric hydrodrive control system - Google Patents

Volumetric hydrodrive control system Download PDF

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Publication number
SU736884A3
SU736884A3 SU752178649A SU2178649A SU736884A3 SU 736884 A3 SU736884 A3 SU 736884A3 SU 752178649 A SU752178649 A SU 752178649A SU 2178649 A SU2178649 A SU 2178649A SU 736884 A3 SU736884 A3 SU 736884A3
Authority
SU
USSR - Soviet Union
Prior art keywords
valve
pump
pressure
fluid
servomotor
Prior art date
Application number
SU752178649A
Other languages
Russian (ru)
Inventor
Х.Борн Эллис
Е.Адамс Сесил
Л.Терстон Давид
Х.Вейлз Алан
Original Assignee
Абекс Корпорейшн (Фирма)
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
Priority to US51527074 priority Critical patent/US3908519A/en
Application filed by Абекс Корпорейшн (Фирма) filed Critical Абекс Корпорейшн (Фирма)
Application granted granted Critical
Publication of SU736884A3 publication Critical patent/SU736884A3/en

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00Control, 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
    • F04B49/002Hydraulic systems to change the pump delivery
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01BMACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/10Control of working-fluid admission or discharge peculiar thereto
    • F01B3/103Control of working-fluid admission or discharge peculiar thereto for machines with rotary cylinder block
    • F01B3/106Control of working-fluid admission or discharge peculiar thereto for machines with rotary cylinder block by changing the inclination of the swash plate
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/26Control
    • F04B1/30Control of machines or pumps with rotary cylinder blocks
    • F04B1/32Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block
    • F04B1/324Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block by changing the inclination of the swash plate
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00Control, 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
    • F04B49/08Regulating by delivery pressure

Abstract

1522027 Reciprocating pumps ABEX CORP 23 Sept 1975 [16 Oct 1974] 39049/75 Heading F1A [Also in Divisions F2 and G3] A variable displacement pump has its rocker cam 34 connected to a pivoted vane servomotor in which chambers 80, 81 communicate with ports 98, 97 having a moving-seat follow-up relationship with an input port 134 in a manually-operated valve 118, the pressure of the fluid supplied to and exhausted from the servomotor being automatically limited to values dependent on the pressure supplied by a servo pump 52 and the pressure of the fluid delivered by the variable displacement pump being limited by means which override the manual control of the servomotor. Check-valves 107, 108 and restrictors 109, 110 restrict exhaust flow from the servomotor while allowing a high flow into it. Flow through the pump is reversible so that either port P1 or P2 may be the output port. When P1 is the delivery port, and fluid pressure is excessive, output pressure acts through lines 249, 255 and 256 on a pilot valve 247 which lifts and allows a valve 203 to lift and establish communication from a line 248 through a line 269 to the chamber 80 to reduce the pump output. A further valve 207 loaded through a line 212 by pressure from the servo pump 52 lifts if the flow from the valve 203 is more than twice servo pressure and allows the excess flow to pass into a circuit 230 communicating with the pump inlet P2 through a check-valve 224. Excess pressure in the circuit 230 is relieved by a valve 201 delivering into the pump case 11 which is connected through a further relief valve 202 to tank. A valve 208, corresponding to the valve 207, but arranged to be loaded by half the pressure from the servo pump through two restrictors 285, 287 and a check-valve 289 limits the pressure in the exhaust chamber of the servomotor to servo pressure and spills any surplus into the circuit 230. Restrictors 205, 206 provide a pressure drop to operate the valve 203, or a valve 204 when P2 is the delivery port, to operate the servomotor in response to excess flow while a further valve 200 loaded through a plunger 218 by the output pressure from the variable displacement pump provides a relief valve for the servo pump 52, excess flow passing through the valve 201. Fluid spilled through the latter valve flows through passages 244 to cool the port plate of the pump before passing into the case 11. If the inlet port demands more fluid than the circuit 230 can supply, pressurized fluid from the pump case flows back through the passages 244 and the valve 201. The shaft 112 has a handle (111) Fig. 3 (not shown) at one end to operate the follow-up valve 118 and an indicator (140) at its other end.

Description

(54) OBJECT MANAGEMENT SYSTEM

one

This invention relates to volumetric hydraulic actuators, in particular with a closed circulation loop between the pump and the hydraulic motor.

A known system for controlling a volumetric hydraulic drive with a closed circulation circuit, equipped with a make-up system, with a variable flow direction in the hydrolines of this circuit, contains the main pump, changing its displacement volume by turning the regulating element through an actuating hydraulic motor with variable volume chambers controlled by a switchgear manual control action, providing alternate communication of these chambers with the pressure hydroline of the control pump, equipped with second overflow valve or discharge depending on the desired value of the working volume of the main pump 1.

However, its relative inertia during overloads leads to significant overshoots of the upper limit, overpressure in the closed-loop pressure line. HYDRAULIC DRIVE

The purpose of the invention is to increase the speed of response to the sieperpysk, except for the high pressure injection in the closed loop hydraulic line above a predetermined level, regardless of the position of the switchgear with manual control action, as well as the automatic return of the pump regulator to the original manual control position after removal of overload. This is achieved

10 in that the control pump overflow valve of the control pump is equipped with a device for changing the level of its adjustment depending on the change in the pressure overpressure level in the closed pressure hydraulic line

(5 contours, made in the form of an additional hydraulic circuit connected to the pressure hydraulics of the closed circuit, the plunger of which interacts with the h;;: the overflow valve, and each of the hydraulic lines of the closed circuit is provided with an indirect action safety valve, the output of which is connected with an additional hydraulic line to the corresponding 1c n camera variable volume executive

-3, ...

the hydraulic motor and said additional gdrolini are connected to the inlet of the additional differential safety valve, the control cavity of which, through the throttle, communicates with the porous hydraulic line of the control pump, and the output from this valve is connected with the main circuit make-up system to provide two different levels of overpressure in the additional hydraulic line - the first (smaller) for the period of increasing the volume of the corresponding chamber of the variable volume of the executive hydraulic motor and the second (more st) - by umenschenie last.

FIG. 1 shows the proposed volumetric hydraulic drive; in fig. 2 shows the main pump of a volumetric hydraulic drive, a longitudinal section; in fig. 3 shows a regulating element of a pump with an actuating hydraulic motor; in fig. 4 shows a regulating element of a pump with an actuating hydraulic motor in a disassembled state; in fig. Figure 5 shows the hydraulic circuit of the hydraulic control system.

The volumetric hydraulic drive with a closed circuit 1irculation contains the main pump 1 and the hydraulic motor 2 interconnected by hydrolines 3 and 4. The internal cavities of the pump 1 and the hydraulic motor 2 communicate with each other by means of the hydroline 5, and with the hydraulic line 6 with the valve 8. In addition, the hydraulic drive contains a control pump (not shown in Fig. 1) embedded in the main, pump 1. The control pump inlet is connected to the hydraulic tank 6 by means of 9 hydraulic lines.

The main pump 1 includes a housing 10 with covers 11 and 12. In the housing 10, a cylinder block 14 with piston groups 15 is mounted on the bearing 13, the supporting bashmaks 16 of which interact with the supporting disk 17 mounted on the movable swing cam 18, which is adjustable element of the pump. The cylinder block 14 is matched to the slots with a drive shaft 19 mounted on a bearing 20, and has, at the end face facing the lid 12, working windows 21 communicated with working chambers 22. A distribution disk 23 is installed between the cylinder block 14 and the lid 12, having two bridged working windows 24 and 25, which are connected to channels 26 and 27 with lids 12. One of the “1X” channels is inlet and serves for the passage of a fluid with a low overpressure, and the other - an outlet that serves to pass the fluid; high overpressure in The dependence on the direction of flow of fluid in a closed circulation circuit between pump 1 and the hydraulic motor 2, ie, passage 26 communicates with hydraulic line 3, and the channel 27 -.. from the hydraulic line 4. The cover 12

736884

A control pump 28 is installed, the drive shaft 29 of which is splined to the cylinder block 14. The cylinder cylinder 14 of the cylinder 14 is pressed into the distribution disk 24 by a spring 30. The change in displacement of the pump 1 is made by turning the cam element 18 by means of an actuating hydraulic motor with variable volume chambers. switchgear with manual control action. Executive hydraulic motor

c has a “symmetrical with respect to the swinging cam 18 design. Below is a description of its left side, and the same elements located on the right side will also have a positional notation with the index “approx.

The swinging cam 18 has an arc cylindrical support surface 31, which mates with a corresponding surface 32 formed on the support 33 installed in the flap 11, and rotates around a fixed axis perpendicular to the axis of the cylinder block 14. The cam 18 has a boss 34, in the slot of which placed sealing element 35. On the support 33 is fixed to the housing 36 with an internal arcuate hole 37, which includes a boss 34. The housing 36 is provided with a cover 38. Thus, the boss 34 and the sealing element 35 divides the arcuate hole 37 in a housing 36 with a cover 38 into two variable volume chambers 39 and 40. Between

0, the housing 36 and the swing cam 18 are fitted with an elastic seal 41 sealing the chambers 39 and 40. The chambers 39 and 40 on one side of the support 33 are connected by channels 42 and 43 with similar chambers located on the other side.

The control device of the actuating hydraulic motor contains a plate 44 mounted on a spacer 45 fixed on the cam 18 by means of clamp 46 (the plate 44 and the spacer 45 are fixed with screws 47). Plate 44 has a pair of holes 48 and 49, which are connected to the corresponding chambers 39 and 40 by channels 50 and 51. When the hydraulic actuator is turned against, in the direction of the clockwise direction, the pressure is supplied to the hole 48 and through the channel 50 enters the chamber 39 to move the lug 34 and swing cam 18 against movement

 hour hand. An increase in the volume of chamber 39 entails a decrease in the volume of chamber 40, the fluid from the latter through channel 51 and opening 49 is displaced into the casing 10 of pump 1. When the actuator motor rotates in the direction of the clockwise rotation, the fluid flow reverses - pressurized fluid flows to the opening 19 49 and The channel 51 enters the chamber 40 to move the boss 34 and the swinging cam 18 in the clockwise direction. The volume of chamber 40 is increased, and chamber 39 is reduced and fluid from the latter is channeled through channel 50 and hole 48 into pump 10 casing 10. Channels 50 and 51 have check valves 52 and 53 and throttles 54 and 55, which ensures free flow of fluid. into the chamber, the volume of which increases and creates a prop in the chamber, the volume of which decreases, i.e. these elements are installed to limit the speed of the actuating hydraulic motor and, therefore, the swing cam 18.

The switchgear of the actuating hydraulic motor also has a manual actuating arm 56, which is mounted on an axis 57 mounted in a cover 58 attached to the housing 10. A lever 59 with an opening 60, in which two shoes 61 and 62 are mounted, is attached to the axis 57-. When the handle 56 is rotated, the shoe 61 slides along the flat surface of the cover 58, and the shoe 62 over the flat surface of the plate 44. The cover 58 in the area of the movement path of the shoe 61 has an opening (not shown in Fig. 4) into which fluid is supplied through the channel 63 pressure by controlling the pump 28. The shoes 61 and 62 are provided with windows 64, each of length equal to the distance between the holes 48 and 49 of the plate 44, and holes 60 are sealed relatively sealing rings 65. Between the washers 66 in the bore 60 a spring washer

67, while preloading the supporting surfaces of the shoes 61 and 62 to the corresponding surfaces of the cover 58 and the plate 44.

On the right side of the cam 18 on the axis 57 instead of the handle 56 there is a pointer

68, showing the exact angular position of the cam 18. The executive hydraulic motor works as follows. At the neutral position of the handle 56, the window 64 in the shoe 62 is located between the openings 48 and 49, which are blocked by the supporting shoe of the shoe 62. To change the displacement of the pump 1, the control handle 56 moves to the desired position. For example, the movement of the handle 56 clockwise moves the shoes 61 and 62 clockwise and sets the window 64 coaxially to the hole 49, the hole 48 opens. The pressurized fluid from the control pump 28 through the channel 63 enters the window 64 of the shoe 61 and further into the window 64 of the shoe 62, from where through the hole 49 and the channel 51 into the chamber 40. At the same time, the liquid is expelled from the chamber 39 through the channel 50 and the hole 48 of the plate 44 Fitted into the casing 10 of the pump 1. A change in the volume of the chambers 39 and 40 causes the swinging cam 18 to rotate in the direction of clockwise rotation, as described above. After moving the cam 18 to the same angle as the handle 56, the window 64 is installed between the openings 48 and 49 of the plate 44 and the executing 5 hydraulics valve stops. In addition, the manual control action on the actuating hydraulic motor of the invention provides for an automatic control system for the pump 1 displacement volume. The main elements of the automatic control system are mounted on the cover 12 of the pump 1. As it was before, the control pump 28 injects fluid under pressure through the channel 63 to the switchgear executive hydraulic motor. The pressure in the pressure line 69 of the pump 28 is controlled by the overflow valve 70. Since the force required to turn the rocker cam 18 increases with increasing pressure developed by the main pump 1,

0, the overflow valve 70 is controlled so that the control pressure varies directly with the pressure in the discharge line of the closed-loop hydraulic circuit.

5 The excess fluid in the control system is discharged through the overflow valve 70 to the closed circuit make-up and circulation system, while the pressure in the closed-loop discharge line is controlled by the retaining valve 71, and the excess liquid in the make-up system is discharged through this valve into the body 10. The scheme provides As mentioned above, a retaining valve 8, which maintains a predetermined level of fluid overpressure inside the housing 10. Maintaining a given level of overpressure in the casing 10 of pump 1 provides for feeding a closed circulation loop through valve 71, if the entire volume flow of the control pump 28 is used for the rapid movement of the actuating hydraulic motor, which can occur with a sharp loading of the hydraulic motor 2.

Claims (1)

1. Prokofiev V.N. and others. Axial-piston adjustable hydraulic drive. M., “Mechanical Engineering, 1969, p. 25, fig. 1.23.
FIG. one
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sixteen
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SU752178649A 1974-10-16 1975-10-10 Volumetric hydrodrive control system SU736884A3 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US51527074 US3908519A (en) 1974-10-16 1974-10-16 Control systems for a variable displacement pump

Publications (1)

Publication Number Publication Date
SU736884A3 true SU736884A3 (en) 1980-05-25

Family

ID=24050665

Family Applications (1)

Application Number Title Priority Date Filing Date
SU752178649A SU736884A3 (en) 1974-10-16 1975-10-10 Volumetric hydrodrive control system

Country Status (16)

Country Link
US (1) US3908519A (en)
JP (1) JPS6127592B2 (en)
AU (1) AU472949B2 (en)
BR (1) BR7506777A (en)
CA (1) CA1032441A (en)
CH (1) CH617248A5 (en)
DE (1) DE2545362C2 (en)
ES (1) ES441550A1 (en)
FR (1) FR2288236B1 (en)
GB (1) GB1522027A (en)
IN (1) IN142703B (en)
IT (1) IT1047520B (en)
MX (1) MX147117A (en)
NL (1) NL178807C (en)
SE (1) SE407101B (en)
SU (1) SU736884A3 (en)

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DE2451380C2 (en) * 1974-10-29 1985-08-14 Linde Ag, 6200 Wiesbaden, De
US3982470A (en) * 1975-08-04 1976-09-28 Abex Corporation Control system for axial piston fluid energy translating device
US4029439A (en) * 1975-12-22 1977-06-14 Abex Corporation Control system for variable displacement pumps
US4008004A (en) * 1975-12-22 1977-02-15 Abex Corporation Control system for variable displacement pumps
US4076459A (en) * 1976-09-14 1978-02-28 Abex Corporation Horsepower limiter control for a variable displacement pump
US4142841A (en) * 1977-08-31 1979-03-06 Parker-Hannifin Corporation Variable displacement pump control
US4476680A (en) * 1979-08-14 1984-10-16 Sundstrand Corporation Pressure override control
US4336003A (en) * 1980-08-11 1982-06-22 Abex Corporation Crane swing control
DE3238362A1 (en) * 1982-10-15 1984-04-19 Linde Ag Axial piston machine
US4455124A (en) * 1982-12-20 1984-06-19 Abex Corporation Automatic pressure setting adjustment for a pressure compensated pump
GB2144242B (en) * 1983-07-26 1987-07-22 Linde Ag A machine control arrangement
US4617797A (en) * 1984-05-09 1986-10-21 Sundstrand Corporation Multi-function valve
US4722186A (en) * 1986-01-24 1988-02-02 Sundstrand Corporation Dual pressure displacement control system
US4768340A (en) * 1987-04-24 1988-09-06 Allied-Signal Inc. Automatic displacement control for variable displacement motor
US4892465A (en) * 1988-09-14 1990-01-09 Hagglunds Denison Corporation Automatic control for variable displacement pump
US5076145A (en) * 1990-06-04 1991-12-31 Hagglunds Denison Corporation Axial piston pump having a blocking valve in a manually controlled valve plate
US5590579A (en) * 1995-10-31 1997-01-07 Eaton Corporation Hydrostatic pump and bearing-clocking mechanism therefor
US6889595B1 (en) 1999-07-16 2005-05-10 Hydro-Gear Limited Partnership Pump
US6694729B1 (en) 1999-07-16 2004-02-24 Hydro-Gear Limited Partnership Pump
US7178336B1 (en) 1999-07-16 2007-02-20 Hydro-Gear Limited Partnership Pump
US7082762B1 (en) 1999-07-16 2006-08-01 Hydro-Gear Limited Partnership Pump
US6332393B1 (en) 1999-07-16 2001-12-25 Hydro-Gear Limited Partnership Pump
US6672843B1 (en) 2002-04-08 2004-01-06 Hydro-Gear Limited Partnership Dual pump apparatus comprising dual drive shafts and auxiliary pump
US6893228B2 (en) * 2002-11-22 2005-05-17 Caterpillar Inc Axial piston pump with fluid bearing arrangement
US7562944B2 (en) * 2002-12-16 2009-07-21 Walker Frank H Hydraulic regenerative braking system for a vehicle
US6953327B1 (en) 2003-03-11 2005-10-11 Hydro-Gear Limited Partnership Dual pump
US7107892B2 (en) * 2003-03-26 2006-09-19 Parker-Hannifin Housing with multiple case drain ports for hydrostatic transmission pumps
WO2006066156A2 (en) * 2004-12-17 2006-06-22 Walker Frank H Hydraulic regenerative braking system and method for a vehicle
US7789846B2 (en) * 2005-01-25 2010-09-07 Thermopeutix, Inc. System and methods for selective thermal treatment
WO2006122241A2 (en) * 2005-05-11 2006-11-16 Walker Frank H Hydraulic regenerative braking system for a vehicle
US8176838B2 (en) * 2007-02-12 2012-05-15 Walker Frank H Hydraulic machine arrangement
US8162621B2 (en) * 2007-02-12 2012-04-24 Walker Frank H Hydraulic machine arrangement
US8974203B2 (en) * 2007-04-03 2015-03-10 Parker-Hannifin Corporation Hydraulic pump end cover

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DE1154689B (en) * 1960-07-09 1963-09-19 Linde Eismasch Ag Device for controlling a continuously variable hydrostatic unit
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US3187509A (en) * 1964-09-16 1965-06-08 Sundstrand Corp Hydrostatic transmission
US3383857A (en) * 1966-05-24 1968-05-21 Borg Warner Hydrostatic transmission mechanism
US3396536A (en) * 1966-08-08 1968-08-13 Cessna Aircraft Co Hydraulic transmission
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Also Published As

Publication number Publication date
NL178807B (en) 1985-12-16
CA1032441A1 (en)
DE2545362C2 (en) 1984-05-24
CH617248A5 (en) 1980-05-14
US3908519A (en) 1975-09-30
SE7511568L (en) 1976-04-17
CA1032441A (en) 1978-06-06
IT1047520B (en) 1980-10-20
JPS5157001A (en) 1976-05-19
FR2288236B1 (en) 1979-02-16
ES441550A1 (en) 1977-04-01
AU8478675A (en) 1976-06-10
IN142703B (en) 1977-08-20
GB1522027A (en) 1978-08-23
BR7506777A (en) 1976-08-17
AU472949B2 (en) 1976-06-10
MX147117A (en) 1982-10-11
FR2288236A1 (en) 1976-05-14
SE407101B (en) 1979-03-12
DE2545362A1 (en) 1976-04-22
NL7510658A (en) 1976-04-21
JPS6127592B2 (en) 1986-06-26
NL178807C (en) 1986-05-16

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