CN105673373A - Constant-pressure variable axial plunger pump with adjustable zero load flow - Google Patents
Constant-pressure variable axial plunger pump with adjustable zero load flow Download PDFInfo
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- CN105673373A CN105673373A CN201610090948.XA CN201610090948A CN105673373A CN 105673373 A CN105673373 A CN 105673373A CN 201610090948 A CN201610090948 A CN 201610090948A CN 105673373 A CN105673373 A CN 105673373A
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- 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
- F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
- F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
- F04B1/26—Control
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- 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
- F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
- F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
- F04B1/122—Details or component parts, e.g. valves, sealings or lubrication means
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
- Control Of Positive-Displacement Pumps (AREA)
Abstract
The invention discloses a constant-pressure variable axial plunger pump with adjustable zero load flow, which is used for solving the technical problem that the zero load flow of existing constant-pressure variable axial plunger pumps cannot be adjusted. According to the technical scheme, the constant-pressure variable axial plunger pump with adjustable zero load flow comprises a constant-pressure valve and a variable shell, wherein a variable piston upper cavity, a variable piston and a variable piston lower cavity are arranged in the variable shell; the variable piston is connected with a variable head by a hinge pin; the lower end of the variable shell is connected with a hydraulic cylinder; a piston, a piston rod and a second spring are arranged in the hydraulic cylinder; the piston is connected with the piston rod; the second spring is arranged on the piston rod; a hydraulic pump is used for supplying oil for the hydraulic cylinder; and pressure can be adjusted and controlled by a three-position four-way reversing valve, a first overflow valve and a second overflow valve. The variable piston cannot continue to move downwards when contacting with the piston rod of the hydraulic rod by moving downwards, and the inclination angle of the variable head cannot reach a maximal value, thus reducing the oil mass output of the plunger pump in zero load, and therefore, flow and pressure in zero load can be controlled in levels, and the purpose of saving energy can be achieved.
Description
Technical field
The present invention relates to a kind of ram pump, particularly relate to a kind of unloaded flow adjustable constant-pressure axial variable displacement plunger pump.
Background technology
Ram pump is an important device of hydraulic efficiency system. It relies on plunger to-and-fro movement in cylinder body, the volume of seal operation cavity volume is changed and realizes oil suction, force feed. Ram pump has the advantages such as rated pressure height, compact construction, efficiency height and Flow-rate adjustment convenience, is widely used in the occasion that high pressure, large discharge and flow need to regulate, in such as hydropress, engineering machinery and boats and ships. Axial plunger pump is the vibration-direction of piston or the plunger ram pump parallel with cylinder body central shaft. Axial plunger pump is that the volume change utilizing plunger plunger hole in the to-and-fro movement parallel with transmission shaft to produce carries out work. Owing to plunger and plunger hole are all circular pieces, add the precision that can reach very high man-hour and coordinate, therefore volumetric efficiency height.
Document 1 Chinese utility model patent of CN204610163U " Authorization Notice No. be " discloses a kind of dual rotation constant-pressure variable axial plunger pump. This ram pump comprises the pump housing and pump cover, and pump cover is provided with the first oil mouth and the 2nd oil mouth, and fuel-displaced valve block and fuel charging valve block are fixed on pump cover. The pump of this kind of variable form, when exporting pressure and be less than set pressure, delivery pressure oil output, namely quantitatively exports; When exporting pressure and reach predetermined pressure, just automatically regulate the flow of pump, to keep this constant pressure, and then meet system requirement. Therefore, when pump is when low load, variable piston motion keeps full flow to export to limit position, and flow can not regulate. If adopting throttle valve adjustment flow between hydro-pump and displacement cylinder, then can improve hydro-pump and export pressure, increase energy consumption, increase system heat generation.
Document 2 Chinese utility model patent of CN201763723U " Authorization Notice No. be " discloses a kind of two constant voltage two-stage axial variable displacement plunger pump, and this ram pump comprises high pressure constant pressure valve, low pressure constant pressure valve and double-acting oil cylinder variable device. When system pressure is less than low-pressure adjusting definite value, hydraulic efficiency oil delivery exports; When hydraulic pressure power reaches low-pressure adjusting constant-pressure, hydraulic efficiency oil discharge capacity is decreased to required value; Pressure continues to strengthen, when reaching the setting value of high pressure constant pressure valve, it is achieved Isobarically Control. This ram pump can only realize the unloaded flow control of one-level, cannot realize Multistage Control.
Summary of the invention
In order to overcome the deficiency that the unloaded flow of existing constant-pressure variable axial plunger pump cannot regulate, the present invention provides a kind of unloaded flow adjustable constant-pressure axial variable displacement plunger pump.This ram pump comprises constant pressure valve and variable shell, and described variable shell inside is provided with under variable piston upper chamber, variable piston and variable piston chamber; Described variable piston is connected with variable head by bearing pin; Under described variable shell, termination has hydro-cylinder, and hydro-cylinder inside is provided with piston, piston rod and the 2nd spring, and piston is connected in piston rod, and piston rod is provided with the 2nd spring; Described hydro-cylinder, by hydro-pump fuel feeding, carrys out regulable control pressure by three position four-way directional control valve, the first surplus valve, the 2nd surplus valve. When variable piston down touches the piston rod of hydro-cylinder, cannot continuing to move downward, the inclination angle of variable head cannot reach maximum, reduces the oil amount output of ram pump when zero load. Such that it is able to flow when stepped control is unloaded and pressure, reach energy-conservation object.
The technical solution adopted for the present invention to solve the technical problems is: a kind of unloaded flow adjustable constant-pressure axial variable displacement plunger pump, being characterized in comprising constant pressure valve 3 and variable shell 6, described variable shell 6 inside is provided with under variable piston upper chamber 4, variable piston 5 and variable piston chamber 7; Described variable piston 5 is connected with variable head 13 by bearing pin 12; Described variable shell 6 times terminations have hydro-cylinder 11, and hydro-cylinder 11 inside is provided with piston 10, piston rod 9 and the 2nd spring 8, and piston 10 is connected on piston rod 9, and piston rod 9 is provided with the 2nd spring 8, it is possible to piston 10 is resetted; Described hydro-cylinder 11, by hydro-pump 20 fuel feeding, sets up control pressure by three position four-way directional control valve 19, first surplus valve 17 and the 2nd surplus valve 18.
When ram pump works, pressure oil output inputs to the control oil-in 14 of chamber 7 and constant pressure valve 3 under variable piston simultaneously, when ram pump is when setting up constant pressure and work, the oil pressure thrust acted on constant voltage spool 2 equals the first spring 1 elastic force, oil-in 15 and the oil discharge outlet 16 of constant pressure valve 3 are in opened condition simultaneously, under variable piston upper chamber 4 and variable piston, the oil pressure thrust in chamber 7 is equal, makes variable piston 5 be equilibrated at a certain working position. If hydraulic efficiency oil damping strengthens, oil pressure raises instantaneously, the oil discharge outlet 16 of constant pressure valve 3 is opened greatly, oil-in 15 closes little, variable piston upper chamber 4 is lower than chamber under variable piston 7 pressure, and variable piston 5 moves up, and the flow of ram pump reduces, until pressure drop is to setting up constant pressure, this variations per hour piston 5 is in new equilibrium theory of tide. If hydraulic efficiency oil damping reduces, the instantaneous decline of oil pressure, the oil-in 15 of constant pressure valve 3 is opened greatly, and oil discharge outlet 16 closes little, and variable piston upper chamber 4 is higher than chamber under variable piston 7 oil pressure, and variable piston 5 moves down. When exporting pressure and be less than set pressure, the oil pressure thrust acted on constant voltage spool 2 is less than the first spring 1 power, and constant pressure valve 3 is in opened condition, pressure oil enters variable piston upper chamber 4, variable piston 5 is pressed in extreme lower position, and variable head 13 inclination angle is maximum, ram pump delivery pressure oil output.
After variable piston 5 contacts with the piston rod 9 of hydro-cylinder 11, when the pressure suffered by piston rod 9 and the 2nd spring 8 and the pressure equilibrium suffered by variable piston 5, variable piston 5 cannot continue to move downward, limit the limit position that variable piston 5 moves downward, the inclination angle of variable head 13 cannot continue to increase, and defines the output flow of ram pump when low load. When the right position of three position four-way directional control valve 19 is connected, the first surplus valve 17 accesses; When the left position of three position four-way directional control valve 19 is connected, the 2nd surplus valve 18 accesses, and hydro-cylinder 11 pressure is carried out three class control, the three class control of output flow when final realization is unloaded to ram pump.
Changing the coupling of the first surplus valve 17, the 2nd surplus valve 18 and three position four-way directional control valve 19, the pressure changing hydro-cylinder 11 is differential, it is achieved the one-level of unloaded flow, two-stage or Multistage Control arbitrarily.
The invention has the beneficial effects as follows: this ram pump comprises constant pressure valve and variable shell, described variable shell inside is provided with under variable piston upper chamber, variable piston and variable piston chamber; Described variable piston is connected with variable head by bearing pin; Under described variable shell, termination has hydro-cylinder, and hydro-cylinder inside is provided with piston, piston rod and the 2nd spring, and piston is connected in piston rod, and piston rod is provided with the 2nd spring; Described hydro-cylinder, by hydro-pump fuel feeding, carrys out regulable control pressure by three position four-way directional control valve, the first surplus valve, the 2nd surplus valve. When variable piston down touches the piston rod of hydro-cylinder, cannot continuing to move downward, the inclination angle of variable head cannot reach maximum, reduces the oil amount output of ram pump when zero load. It is thus possible to flow when stepped control is unloaded and pressure, reach energy-conservation object.
Below in conjunction with the drawings and specific embodiments, the present invention done detailed explanation.
Accompanying drawing explanation
Fig. 1 is the structural representation of the unloaded flow adjustable constant-pressure axial variable displacement plunger pump of the present invention.
Fig. 2 is the variable characteristics curve of the unloaded flow adjustable constant-pressure axial variable displacement plunger pump of the present invention.
Fig. 3 is the unloaded flow adjustable constant-pressure axial variable displacement plunger pump hydraulic efficiency system sketch of the present invention.
In figure, 1-first spring; 2-constant voltage spool; 3-constant pressure valve; 4-variable piston upper chamber; 5-variable piston; 6-variable shell; Chamber under 7-variable piston; 8-the 2nd spring; 9-piston rod; 10-piston; 11-hydro-cylinder; 12-bearing pin; 13-variable head; 14-controls oil-in; 15-oil-in; 16-oil discharge outlet; 17-first surplus valve; 18-the 2nd surplus valve; 19-three position four-way directional control valve; 20-hydro-pump.
Embodiment
With reference to Fig. 1～3. The unloaded flow adjustable constant-pressure axial variable displacement plunger pump of the present invention comprises constant pressure valve 3, variable shell 6, and described variable shell 6 inside is provided with under variable piston upper chamber 4, variable piston 5, variable piston chamber 7; Described variable piston 5 is connected with variable head 13 by bearing pin 12; Described variable shell 6 times terminations have hydro-cylinder 11, and hydro-cylinder 11 inside is provided with piston 10, piston rod 9, the 2nd spring 8, and piston 10 is connected in piston rod 9, and piston rod 9 is provided with the 2nd spring 8 (piston 10 can be resetted); Described hydro-cylinder 11, by hydro-pump 20 fuel feeding, sets up control pressure by three position four-way directional control valve 19, first surplus valve 17, the 2nd surplus valve 18.
When ram pump works, pressure oil output inputs to the control oil-in 14 of chamber 7 and constant pressure valve 3 under variable piston simultaneously, when ram pump is when setting up constant pressure and work, the oil pressure thrust acted on constant voltage spool 2 equals the first spring 1 elastic force, oil-in 15, the oil discharge outlet 16 of constant pressure valve 3 are in opened condition simultaneously, under variable piston upper chamber 4, variable piston, the oil pressure thrust in chamber 7 is equal, makes variable piston 5 be equilibrated at a certain working position. If hydraulic efficiency oil damping (load) strengthens, oil pressure raises instantaneously, constant pressure valve 3 oil discharge outlet 16 leaves greatly, oil-in 15 closes little, variable piston upper chamber 4 is lower than chamber under variable piston 7 pressure, variable piston 5 moves up, the flow of ram pump reduces, until pressure drop is to setting up constant pressure, this variations per hour piston 5 is in new equilibrium theory of tide.Otherwise, hydraulic damping (load) reduces, and the instantaneous decline of oil pressure, constant pressure valve 3 oil-in 15 leaves greatly, and oil discharge outlet 16 closes little, and variable piston upper chamber 4 is higher than chamber under variable piston 7 oil pressure, and variable piston 5 moves down. When exporting pressure and be less than set pressure, the oil pressure thrust acted on constant voltage spool 2 is less than the first spring 1 power, and constant pressure valve 3 is in opened condition, pressure oil enters variable piston upper chamber 4, variable piston 5 is pressed in extreme lower position, and variable head 13 inclination angle is maximum, ram pump delivery pressure oil output.
After variable piston 5 contacts with the piston rod 9 of hydro-cylinder 11, when the pressure suffered by piston rod 9 and the 2nd spring 8 and the pressure equilibrium suffered by variable piston 5, variable piston 5 cannot continue to move downward, limit the limit position that variable piston 5 moves downward, thus the inclination angle of variable head 13 cannot continue to increase, and defines the output flow of ram pump when low load. When the right position of three position four-way directional control valve 19 is connected, (set pressure is P to the first surplus valve 171) access; When the left position of three position four-way directional control valve 19 is connected, (set pressure is P to the 2nd surplus valve 182) access, thus reach the object to hydro-cylinder 11 pressure three class control (containing 0 pressure state), the three class control of output flow when final realization is unloaded to ram pump.
By changing the coupling of the first surplus valve 17, the 2nd surplus valve 18 and three position four-way directional control valve 19, the pressure changing hydro-cylinder 11 is differential, it is possible to realize the one-level of unloaded flow, two-stage and Multistage Control arbitrarily.
Claims (2)
1. a unloaded flow adjustable constant-pressure axial variable displacement plunger pump, it is characterized in that: comprise constant pressure valve (3) and variable shell (6), described variable shell (6) inside is provided with under variable piston upper chamber (4), variable piston (5) and variable piston chamber (7); Described variable piston (5) is connected with variable head (13) by bearing pin (12); Under described variable shell (6), termination has hydro-cylinder (11), hydro-cylinder (11) inside is provided with piston (10), piston rod (9) and the 2nd spring (8), piston (10) is connected on piston rod (9), piston rod (9) is provided with the 2nd spring (8), it is possible to piston (10) is resetted; Described hydro-cylinder (11), by hydro-pump (20) fuel feeding, sets up control pressure by three position four-way directional control valve (19), the first surplus valve (17) and the 2nd surplus valve (18);
When ram pump works, pressure oil output inputs to the control oil-in (14) of chamber (7) and constant pressure valve (3) under variable piston simultaneously, when ram pump is when setting up constant pressure and work, the oil pressure thrust acted on constant voltage spool (2) equals the first spring (1) elastic force, oil-in (15) and the oil discharge outlet (16) of constant pressure valve (3) are in opened condition simultaneously, under variable piston upper chamber (4) and variable piston, the oil pressure thrust in chamber (7) is equal, makes variable piston (5) be equilibrated at a certain working position; If hydraulic efficiency oil damping strengthens, oil pressure raises instantaneously, the oil discharge outlet (16) of constant pressure valve (3) is opened greatly, oil-in (15) closes little, variable piston upper chamber (4) is lower than chamber under variable piston (7) pressure, and variable piston (5) moves up, and the flow of ram pump reduces, until pressure drop is to setting up constant pressure, this variations per hour piston (5) is in new equilibrium theory of tide; If hydraulic efficiency oil damping reduces, the instantaneous decline of oil pressure, the oil-in (15) of constant pressure valve (3) is opened greatly, oil discharge outlet (16) closes little, variable piston upper chamber (4) moves down than chamber under variable piston (7) oil pressure height, variable piston (5); When exporting pressure and be less than set pressure, the oil pressure thrust acted on constant voltage spool (2) is less than the first spring (1) power, constant pressure valve (3) is in opened condition, pressure oil enters variable piston upper chamber (4), variable piston (5) is pressed in extreme lower position, variable head (13) inclination angle is maximum, ram pump delivery pressure oil output;
After variable piston (5) contacts with the piston rod (9) of hydro-cylinder (11), when the pressure suffered by piston rod (9) and the 2nd spring (8) and the pressure equilibrium suffered by variable piston (5), variable piston (5) cannot continue to move downward, limit the limit position that variable piston (5) moves downward, the inclination angle of variable head (13) cannot continue to increase, and defines the output flow of ram pump when low load; When the right position of three position four-way directional control valve (19) is connected, the first surplus valve (17) accesses; When the left position of three position four-way directional control valve (19) is connected, the 2nd surplus valve (18) access, carries out three class control to hydro-cylinder (11) pressure, the three class control of output flow when final realization is unloaded to ram pump.
2. unloaded flow adjustable constant-pressure axial variable displacement plunger pump according to claim 1, it is characterized in that: the coupling changing the first surplus valve (17), the 2nd surplus valve (18) and three position four-way directional control valve (19), the pressure changing hydro-cylinder (11) is differential, it is achieved the one-level of unloaded flow, two-stage or Multistage Control arbitrarily.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610090948.XA CN105673373B (en) | 2016-02-18 | 2016-02-18 | No load discharge adjustable constant-pressure axial variable displacement plunger pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610090948.XA CN105673373B (en) | 2016-02-18 | 2016-02-18 | No load discharge adjustable constant-pressure axial variable displacement plunger pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105673373A true CN105673373A (en) | 2016-06-15 |
| CN105673373B CN105673373B (en) | 2018-02-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610090948.XA Expired - Fee Related CN105673373B (en) | 2016-02-18 | 2016-02-18 | No load discharge adjustable constant-pressure axial variable displacement plunger pump |
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| Country | Link |
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| CN (1) | CN105673373B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109139409A (en) * | 2018-09-30 | 2019-01-04 | 杭州力龙液压有限公司 | Digital constant flow inclined shaft plunger pump |
| CN113530783A (en) * | 2021-07-19 | 2021-10-22 | 中航力源液压股份有限公司 | Two-stage pressure control device with unloading function |
| CN116241426A (en) * | 2022-09-08 | 2023-06-09 | 南京卓益控制技术有限公司 | Hydraulic system's oil pressure electric control mechanism and variable pump |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1024284A2 (en) * | 1999-01-28 | 2000-08-02 | Eaton Corporation | Hydraulic pump control |
| CN201155437Y (en) * | 2007-08-31 | 2008-11-26 | 徐绳武 | Integrated type micro-overflow energy-saving axial pump |
| CN201218172Y (en) * | 2008-07-11 | 2009-04-08 | 宁波恒力液压机械制造有限公司 | Electrohydraulic proportion variable axial plunger pump |
| CN201771702U (en) * | 2010-07-23 | 2011-03-23 | 启东高压油泵有限公司 | Energy-saving hydraulic-control variable axial plunger pump |
| CN204152740U (en) * | 2014-08-21 | 2015-02-11 | 天津市天高液压件有限公司 | A kind of plunger pump deciding grade and level stroking mechanism |
-
2016
- 2016-02-18 CN CN201610090948.XA patent/CN105673373B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1024284A2 (en) * | 1999-01-28 | 2000-08-02 | Eaton Corporation | Hydraulic pump control |
| CN201155437Y (en) * | 2007-08-31 | 2008-11-26 | 徐绳武 | Integrated type micro-overflow energy-saving axial pump |
| CN201218172Y (en) * | 2008-07-11 | 2009-04-08 | 宁波恒力液压机械制造有限公司 | Electrohydraulic proportion variable axial plunger pump |
| CN201771702U (en) * | 2010-07-23 | 2011-03-23 | 启东高压油泵有限公司 | Energy-saving hydraulic-control variable axial plunger pump |
| CN204152740U (en) * | 2014-08-21 | 2015-02-11 | 天津市天高液压件有限公司 | A kind of plunger pump deciding grade and level stroking mechanism |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109139409A (en) * | 2018-09-30 | 2019-01-04 | 杭州力龙液压有限公司 | Digital constant flow inclined shaft plunger pump |
| CN113530783A (en) * | 2021-07-19 | 2021-10-22 | 中航力源液压股份有限公司 | Two-stage pressure control device with unloading function |
| CN116241426A (en) * | 2022-09-08 | 2023-06-09 | 南京卓益控制技术有限公司 | Hydraulic system's oil pressure electric control mechanism and variable pump |
| CN116241426B (en) * | 2022-09-08 | 2023-10-13 | 南京卓益控制技术有限公司 | Hydraulic system's oil pressure electric control mechanism and variable pump |
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| Publication number | Publication date |
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| CN105673373B (en) | 2018-02-06 |
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Granted publication date: 20180206 Termination date: 20220218 |