US3707881A - Control system for hydraulic fluid-feed mechanism - Google Patents
Control system for hydraulic fluid-feed mechanism Download PDFInfo
- Publication number
- US3707881A US3707881A US00121713A US3707881DA US3707881A US 3707881 A US3707881 A US 3707881A US 00121713 A US00121713 A US 00121713A US 3707881D A US3707881D A US 3707881DA US 3707881 A US3707881 A US 3707881A
- Authority
- US
- United States
- Prior art keywords
- valve
- limit control
- piston
- control
- limit
- 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.)
- Expired - Lifetime
Links
- 230000007246 mechanism Effects 0.000 title description 18
- 239000012530 fluid Substances 0.000 claims abstract description 21
- 230000033001 locomotion Effects 0.000 claims abstract description 14
- 230000001360 synchronised effect Effects 0.000 claims description 5
- 230000000977 initiatory effect Effects 0.000 claims description 4
- 238000013459 approach Methods 0.000 claims description 2
- 230000004044 response Effects 0.000 claims description 2
- 230000009471 action Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 230000001133 acceleration Effects 0.000 description 3
- 230000009977 dual effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000003754 machining Methods 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229920001684 low density polyethylene Polymers 0.000 description 1
- 239000004702 low-density polyethylene Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
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
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
- F16K11/02—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit
- F16K11/06—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements
- F16K11/065—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members
- F16K11/07—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members with cylindrical slides
- F16K11/0716—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members with cylindrical slides with fluid passages through the valve member
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L15/00—Valve-gear or valve arrangements, e.g. with reciprocatory slide valves, other than provided for in groups F01L17/00 - F01L29/00
- F01L15/08—Valve-gear or valve arrangements, e.g. with reciprocatory slide valves, other than provided for in groups F01L17/00 - F01L29/00 with cylindrical, sleeve, or part-annularly-shaped valves; Such main valves combined with auxiliary valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L25/00—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means
- F01L25/02—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means by fluid means
- F01L25/04—Drive, or adjustment during the operation, or distribution or expansion valves by non-mechanical means by fluid means by working-fluid of machine or engine, e.g. free-piston machine
- F01L25/06—Arrangements with main and auxiliary valves, at least one of them being fluid-driven
- F01L25/063—Arrangements with main and auxiliary valves, at least one of them being fluid-driven the auxiliary valve being actuated by the working motor-piston or piston-rod
-
- 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
- F04B9/00—Piston machines or pumps characterised by the driving or driven means to or from their working members
- F04B9/08—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid
- F04B9/10—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid
- F04B9/109—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having plural pumping chambers
- F04B9/111—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having plural pumping chambers with two mechanically connected pumping members
- F04B9/113—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having plural pumping chambers with two mechanically connected pumping members reciprocating movement of the pumping members being obtained by a double-acting liquid motor
Definitions
- a T TOR NEYS PATENTEDJM 2 1915 saw 3 or 4 INVENTOR.
- HEI NZ NEUHAUS BY Wadi DR. HENNING PETERS ATTORNEYS CONTROL SYSTEM FOR HYDRAULIC FLUID- FEED MECHANISM BACKGROUND OF THE INVENTION
- the present invention relates to a control system for hydraulic fluid-feed mechanisms intended to produce straight-line reciprocating motions that are typical preferably for piston pumps and plunger pumps and machine tools.
- the hydraulic fluid usually oil
- the working piston moves towards the pressureless cylinder end and, by means of a rigid linkage, its motion is transferred to the working machine, for example to the plungers or pistons of pumps or to the carriages of machine tools.
- Limit control valves or limit switches are intended to effect the change-over of the multiway valve. While fluid delivered by the hydraulic pump is admitted through the multiway valve into the cylinder to one side of the piston, the fluid on the other side of the piston leaves the cylinder at low pressure through the multiway valve into the return or reflux line.
- the control system for hydraulic fluid-feed mechanisms therefore, consists essentially of the two limit control valves or limit switches, the multiway valve and, possible, impulse amplifiers.
- Limit control elements may operate upon the multiway valve either mechanically or through hydraulic, pneumatic or electric transmission.
- the multiway valve must be located in the vicinity of said elements because they operate directly on the multiway valve.
- the disadvantage of these mechanical limit control elements is that they do not open quickly the entire necessary cross-sectional area in the multiway valve for the hydraulic fluid; instead, the rate of opening is proportional to the speed of the reciprocating machine element.
- the multiway valve may be located at a distance from said elements.
- the conventional hydraulically or pneumatically operating limit control valves have, however, the disadvantage that the control piston is actuated through its entire stroke by the reciprocating machine element; this means that the control piston moves at a speed that corresponds to the speed of the reciprocating machine element. This speed, however, is insufficient for the reversing action.
- the reversing action can be shortened by using a pneumatic limit control valve with a very short travel followed by a series of pneumatic amplifiers of progressively upward rating depending on the rating of the hydraulic multiway valve. Obviously, this system is necessarily very expensive.
- a quick reversing action can also be achieved by using an electrically operating control system consisting of limit control element and multiway valve.
- electric control devices also have inherent disadvantages, such as wear of contactors, faulty contacts, difficulties in locating faults in the electric system and an expensive design for use in areas or plants where explosion hazards are encountered.
- the action of force of the return spring is opposed to the direction of motion of the control piston when the interlocking pressure becomes effective.
- the working piston of two or more mechanisms can be connected in parallel in that the limit control valves of one side, i.e., of the same direction of motion, of several mechanisms are interconnected through the interlocking lines of these limit control valves.
- the limit control valves for the opposite direction of motion are not interconnected.
- the invention incorporates the particular advantage that, referring to the limit control valve, a minute initiating stroke measuring a fraction of a millimeter is sufficient to achieve a rapid control stroke of several millimeters and, consequently, to cause a quick breakdown of the pressure on one side of the working piston and a quick build-up of pressure on the opposite side of the piston.
- this method makes it possible to obtain an almost ideal rectangular discharge diagram.
- the pressure on the working piston remains effective until the piston has reached its end position, then breaks down suddenly while becoming fully effective on the opposite side.
- the use of the subject control system results in very short dead periods and, consequently, reduced machining time.
- control cam on the working piston rod will contact the head of the control piston for a short time only and move it a fraction of a millimeter into the valve.
- the return spring then acts to draw the head of the control piston away from the control cam.
- the limit control valve cannot be damaged by the control cam or the working piston rod.
- FIG. 1 is a schematic diagram of a hydraulic cylinder control system constructed according to the invention with the parts shown in neutral positions.
- FIG. 2 is a cross section of a limit control valve or pilot valve used in the control system of FIG. 1, with the valve stem in extended position.
- FIG. 3 is similar to FIG. 2 with the valve stem in retracted position.
- FIG. 4 is a schematic diagram similar to FIG. 1 showing the valve positions as a transfer or reversal of the power cylinder is being completed.
- FIG. 5 is a schematic diagram of two control systems connected for synchronous operation.
- the hydraulic fluid-feed mechanism consists essentially of the system comprising the mechanism and the control and interlocking facilities.
- the fluid is admitted through multiway valve 1 alternately to the two sides of working piston 2 by means of a pump that has been omitted from the drawing for better clarity.
- the fluid returns from the depressurized cylinder end through the multiway valve 1 to a pump suction tank.
- the pump for the control system S the pump has also been omitted from the drawing --produces the constant control pressure ahead of limit control or pilot valves 3 and 3'.
- the interlocking system V consists of the limit control valves with the control lines between limit control valves 3 and 3 and multiway valve 1. Return lines R on the limit control valves are provided to achieve an alternate pressure release on piston 4 in the multiway valve.
- Each of the two limit control valves consists essentially of a valve body 5, two covers 6 and 7, control sleeve 8, control piston 9 and return spring 10.
- Valve body 5 is provided with a pressure control-fluid connection B, a return connection C and a connection D for an interconnecting line between the limit control valve 3 and the multiway valve 1.
- Each cover 6 is provided with a connection E for one of the interlocking lines V. Referring to known control systems, this connection serves for leak oil discharge-
- the limit control valve has two stable positions: a working position and a zero position. In the working position, as shown in FIG. 2, the control piston 9 extends from the valve in position to be actuated by the moving machine, for example a plunger pump.
- connection E the control piston is forced into the extended or working position by the pressure in one line of the interlocking system and against the force of the return spring, the pressure being admitted through connection E.
- the return spring is being compressed.
- Connections D and C are communicating with return line R through piston recess 11 and are, therefore, pressureless.
- Control line 12 connected at D and leading to the multiway valve is also pressureless.
- the control pressure admitted to connection B remains ineffective because the flow from B through piston recess 13 is obstructed.
- a cam 14 on the working piston rod contacts piston head roller 15 of the control piston, the latter will start moving into the valve and establish communication between connection B and connection D through piston recess 13 as may be noted from FIG. 3.
- the control system for a multicylinder mechanism may comprise a plurality of systems as shown in FIG. 5 interconnected to operate in synchronism.
- a first system similar to that shown in FIGS. 1 and 4 is shown in the upper part of the figure and the parts identified with corresponding numerals with a suffix a.
- a second similar system is shown in the lower part of the figure and the parts identified with corresponding numerals with a suffix b.
- the two systems and any others to be operated in synchronism therewith are connected by leads b and c.
- the pump for the fluid-feed is adequately sized to permit simultaneous operation of both working pistons.
- the several fluid-feed mechanisms A are connected to the pump discharge line at a.
- One multiway valve la, lb and two limit control valves 3a, 3'a; 3b, 3'b with control system and interlocking system are associated with each working piston.
- the two control systems are fed from one pump and are interconnected through connection b. Synchronous operation of the two working pistons is achieved by interconnecting the two control lines 12a, 12b through connection c.
- the interlocking lines 18a, 18b are also connected to each other.
- the two limit control valves 3'0, 3b for the opposite direction of travel are not interconnected or interlocked since the pressure changes in the lines 12a, 12b; 18a, 18b as a result of operating one pair of limit control valves can hydraulically operate the other interconnected pairs of valves.
- shutoff valves or change-over valves on the interconnecting lines makes it possible to disconnect individual systems, for example for part-load operation or repair work.
- a control system for a hydraulically actuated valve of a hydraulic power cylinder assembly comprising, in combination, a pair of limit control valves, a spring in each limit control valve for urging the valve in a first direction, a piston and cylinder in each limit valve for urging the valve in a second direction, means responsive to approach of the power cylinder assembly to an end of its stroke for initiating movement of one of the limit control valves, ports in each limit control valve and fluid conduit means connecting a source of contro fluid through the ports in one limit control valve to the piston and cylinder of the other limit control valve and to an end of the hydraulically actuated valve, said piston and cylinder and said spring cooperating to position the limit control valve in response to control fluid supplied through the other limit control valve following an initial movement of one of the limit control valves.
- a limit control valve according to claim 1 in which the spring urges the valve toward its inactive position and the fluid pressure admitted through the other valve to the piston and cylinder urges the valve toward its working position.
- a limit control valve system including fluid conduit means interconnecting first ones of a plurality of pairs of limit control valves in parallel for synchronous operation.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Fluid-Pressure Circuits (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19702011570 DE2011570C (de) | 1970-03-12 | Steuersystem für druckmittelbetriebene Antriebe |
Publications (1)
Publication Number | Publication Date |
---|---|
US3707881A true US3707881A (en) | 1973-01-02 |
Family
ID=5764803
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00121713A Expired - Lifetime US3707881A (en) | 1970-03-12 | 1971-03-08 | Control system for hydraulic fluid-feed mechanism |
Country Status (7)
Country | Link |
---|---|
US (1) | US3707881A (nl) |
JP (1) | JPS5514274B1 (nl) |
CH (1) | CH526051A (nl) |
FR (1) | FR2081893B1 (nl) |
GB (1) | GB1349083A (nl) |
NL (1) | NL168589C (nl) |
SE (1) | SE367461B (nl) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4002103A (en) * | 1974-07-01 | 1977-01-11 | The West Company | Reciprocating apparatus with a controllable dwell time at each end of the stroke |
US4242940A (en) * | 1977-05-30 | 1981-01-06 | Page Victor J | Fluid operated control device |
US4368008A (en) * | 1981-02-10 | 1983-01-11 | Tadeusz Budzich | Reciprocating controls of a gas compressor using free floating hydraulically driven piston |
WO2000077397A1 (fr) * | 1999-06-15 | 2000-12-21 | Bernard Marinzet | Pompe a pistons, procede et installation de filtration d'eau |
WO2005121555A1 (en) * | 2004-06-07 | 2005-12-22 | Hunter Hitech Pty Ltd | A pump assembly |
CN102094780A (zh) * | 2011-01-21 | 2011-06-15 | 晋中开发区宏光实业有限公司 | 液压泥浆泵 |
AU2005252262B2 (en) * | 2004-06-07 | 2011-07-28 | Hitech Hippo Australia Ltd | A pump assembly |
CN102937074A (zh) * | 2012-11-12 | 2013-02-20 | 三一重工股份有限公司 | 连续供料系统及其控制方法、登高平台消防车 |
US20140199182A1 (en) * | 2013-01-11 | 2014-07-17 | Super Products Llc | Reciprocating water pump |
US9233340B1 (en) * | 2015-01-13 | 2016-01-12 | Renergy Technologies Ltd. | Cylinder arrangement and method of use for energy recovery with seawater desalination |
CN106870316A (zh) * | 2017-04-18 | 2017-06-20 | 黄山市汇润机械有限公司 | 一种液压式双作用压力泵橇 |
US20170184090A1 (en) * | 2013-01-11 | 2017-06-29 | Super Products Llc | Reciprocating water pump |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE430532B (sv) * | 1981-01-16 | 1983-11-21 | Blidsberg Verktygsind | System for tillforsel av ett kompressibelt drivmedium |
US4522033A (en) * | 1984-07-02 | 1985-06-11 | Cvi Incorporated | Cryogenic refrigerator with gas spring loaded valve |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1577914A (en) * | 1921-11-08 | 1926-03-23 | Cain John A Le | Steam-engine valve gear |
US2296647A (en) * | 1941-02-28 | 1942-09-22 | Racine Tool & Machine Company | Hydraulic pressure booster |
US2698517A (en) * | 1952-05-21 | 1955-01-04 | Kenneth F Witt | Automatic means to control and reverse fluid-operated cylinder-and-piston units |
US3225663A (en) * | 1963-04-09 | 1965-12-28 | Hispano Suiza Sa | Hydraulic control systems including double action receiver apparatus |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH473319A (de) * | 1968-06-19 | 1969-05-31 | Hydrel Ag Maschf | Vollhydraulische Vorrichtung an Maschine oder Apparat mit geradlinig hin- und hergehendem Teil, für weitgehend last- und geschwindigkeitsunabhängige Genauigkeitsumsteuerung der Bewegung des Teils zwischen zwei einstellbaren Umsteuerpunkten |
-
1971
- 1971-02-08 NL NLAANVRAGE7101639,A patent/NL168589C/nl not_active IP Right Cessation
- 1971-03-08 US US00121713A patent/US3707881A/en not_active Expired - Lifetime
- 1971-03-10 SE SE03080/71A patent/SE367461B/xx unknown
- 1971-03-12 JP JP1314171A patent/JPS5514274B1/ja active Pending
- 1971-03-12 CH CH365771A patent/CH526051A/de not_active IP Right Cessation
- 1971-03-12 FR FR7108679A patent/FR2081893B1/fr not_active Expired
- 1971-04-19 GB GB2391571*A patent/GB1349083A/en not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1577914A (en) * | 1921-11-08 | 1926-03-23 | Cain John A Le | Steam-engine valve gear |
US2296647A (en) * | 1941-02-28 | 1942-09-22 | Racine Tool & Machine Company | Hydraulic pressure booster |
US2698517A (en) * | 1952-05-21 | 1955-01-04 | Kenneth F Witt | Automatic means to control and reverse fluid-operated cylinder-and-piston units |
US3225663A (en) * | 1963-04-09 | 1965-12-28 | Hispano Suiza Sa | Hydraulic control systems including double action receiver apparatus |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4002103A (en) * | 1974-07-01 | 1977-01-11 | The West Company | Reciprocating apparatus with a controllable dwell time at each end of the stroke |
US4242940A (en) * | 1977-05-30 | 1981-01-06 | Page Victor J | Fluid operated control device |
US4368008A (en) * | 1981-02-10 | 1983-01-11 | Tadeusz Budzich | Reciprocating controls of a gas compressor using free floating hydraulically driven piston |
WO2000077397A1 (fr) * | 1999-06-15 | 2000-12-21 | Bernard Marinzet | Pompe a pistons, procede et installation de filtration d'eau |
US6652741B1 (en) | 1999-06-15 | 2003-11-25 | Bernard Marinzet | Piston pump, method and installation for filtering water |
AU2005252262B2 (en) * | 2004-06-07 | 2011-07-28 | Hitech Hippo Australia Ltd | A pump assembly |
US20110044830A1 (en) * | 2004-06-07 | 2011-02-24 | Hunter Hitech Pty Ltd | Pump assembly |
WO2005121555A1 (en) * | 2004-06-07 | 2005-12-22 | Hunter Hitech Pty Ltd | A pump assembly |
CN102094780A (zh) * | 2011-01-21 | 2011-06-15 | 晋中开发区宏光实业有限公司 | 液压泥浆泵 |
CN102937074A (zh) * | 2012-11-12 | 2013-02-20 | 三一重工股份有限公司 | 连续供料系统及其控制方法、登高平台消防车 |
CN102937074B (zh) * | 2012-11-12 | 2015-06-10 | 三一汽车制造有限公司 | 连续供料系统及其控制方法、登高平台消防车 |
US20140199182A1 (en) * | 2013-01-11 | 2014-07-17 | Super Products Llc | Reciprocating water pump |
US20170184090A1 (en) * | 2013-01-11 | 2017-06-29 | Super Products Llc | Reciprocating water pump |
US9233340B1 (en) * | 2015-01-13 | 2016-01-12 | Renergy Technologies Ltd. | Cylinder arrangement and method of use for energy recovery with seawater desalination |
CN106870316A (zh) * | 2017-04-18 | 2017-06-20 | 黄山市汇润机械有限公司 | 一种液压式双作用压力泵橇 |
CN106870316B (zh) * | 2017-04-18 | 2019-06-11 | 黄山市汇润机械有限公司 | 一种液压式双作用压裂泵橇 |
Also Published As
Publication number | Publication date |
---|---|
NL168589B (nl) | 1981-11-16 |
JPS5514274B1 (nl) | 1980-04-15 |
NL168589C (nl) | 1982-04-16 |
GB1349083A (en) | 1974-03-27 |
FR2081893A1 (nl) | 1971-12-10 |
CH526051A (de) | 1972-07-31 |
NL7101639A (nl) | 1971-09-14 |
SE367461B (nl) | 1974-05-27 |
FR2081893B1 (nl) | 1974-10-31 |
DE2011570A1 (de) | 1971-09-30 |
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