CN104358684B - A kind of flow equilibrium device for piston pump - Google Patents

A kind of flow equilibrium device for piston pump Download PDF

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Publication number
CN104358684B
CN104358684B CN201410604996.7A CN201410604996A CN104358684B CN 104358684 B CN104358684 B CN 104358684B CN 201410604996 A CN201410604996 A CN 201410604996A CN 104358684 B CN104358684 B CN 104358684B
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valve
piston
pump
rod
pump housing
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CN104358684A (en
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李强
石海峡
柴立平
张�杰
李跃
宫恩祥
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HEFEI HUASHENG VALVE Ltd BY SHARE Ltd
Hefei University of Technology
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HEFEI HUASHENG VALVE Ltd BY SHARE Ltd
Hefei University of Technology
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Abstract

The invention belongs to piston pump field, be specifically related to a kind of flow equilibrium device for piston pump.This device includes the pump housing and the piston being arranged in the pump housing, and one end of main piston rod is affixed with piston, and the other end of main piston rod stretches out the outside at the pump housing;Pump body is divided into two pump chambers by described piston, two pump chambers are connected with respective feed tube and discharging tube respectively, this device includes dummy piston bar, one end of described dummy piston bar is fixedly installed on the side deviating from main piston rod of piston, and the other end of dummy piston bar stretches out in the outside of the pump housing and is slidably matched with hydraulic buffering mechanism composition;The axis of described dummy piston bar is parallel with the axis of main piston rod or overlaps.Comparing piston pump more of the prior art, the opening speed of the piston in the present invention is more uniform, and flow is more steady, and pulsation more balances, and improves the reliability and stability of piston pump work.

Description

A kind of flow equilibrium device for piston pump
Technical field
The invention belongs to piston pump field, be specifically related to a kind of flow equilibrium device for piston pump.
Background technology
Piston pump is widely used in the fields such as petrochemical industry, Coal Chemical Industry and oil field.Double-acting type piston of the prior art Pump configuration is as it is shown in figure 1, include the pump housing 10 and the piston 30 being arranged in the pump housing 10, and one end of main piston rod 20 is solid with piston 30 Connecing, the other end of main piston rod 20 stretches out the outside at the pump housing 10;Described piston 30 is divided into two pump chambers by internal for the pump housing 10, and two Individual pump chamber is connected with respective feed tube and discharging tube respectively.Due in two pump chambers of the piston pump in said structure All the time there is the cylinder difference in volume that main piston rod 20 volume is formed, when the volume of main piston rod 20 is bigger, cylinder difference in volume can Reach more than 20%, therefore for double-acting piston pump, there is instability of flow, the pulsation shortcoming such as bigger, the pump housing all the time And assembly will persistently bear the fluctuation caused because of larger flow difference and unstability impact, thus easily there is event in piston pump Barrier, reduces service life.
Summary of the invention
It is an object of the invention to overcome above-mentioned the deficiencies in the prior art, it is provided that a kind of flow equilibrium for piston pump fills Putting, this apparatus structure is simple, and good stability has ensured the reliability and stability that piston pump works.
For achieving the above object, present invention employs techniques below scheme:
A kind of flow equilibrium device for piston pump, including the pump housing and the piston being arranged in the pump housing, main piston rod One end is affixed with piston, and the other end of main piston rod stretches out the outside at the pump housing;Pump body is divided into two pumps by described piston Chamber, two pump chambers are connected with respective feed tube and discharging tube respectively, and this device includes dummy piston bar, described balance One end of piston rod is fixedly installed on the side deviating from main piston rod of piston, and the other end of dummy piston bar stretches out at the pump housing Outside is also slidably matched with hydraulic buffering mechanism composition;The axis of described dummy piston bar is parallel with the axis of main piston rod or heavy Close.
Preferably, described dummy piston bar and the shaft equal diameters of main piston rod.
Preferably, described hydraulic buffering mechanism includes the balance set with tubular inner chamber and gland, described dummy piston bar The one end outside the pump housing of stretching out insert in the tubular inner chamber of balance set and constitute with balance set and be slidably matched, described gland seals Being located at the other end of the far from equilibrium piston rod of balance set, described dummy piston bar, balance set and gland enclose hydraulic pressure jointly Chamber;Described gland is provided with buffer solution outlet and buffer inlet;Described hydraulic buffering mechanism also includes connecting buffer solution outlet With the liquid valve group of hydraulic cavities and the liquid feed valve group that connects buffer inlet and hydraulic cavities.
Preferably, it is provided with seal washer between described balance set and gland.
Further, described liquid valve group includes the valve seat being fixedly installed in gland;Described valve seat is tubular, valve seat Near the internal face inwardly protruding formation limiting section of buffer solution outlet side, the side towards hydraulic cavities of described limiting section is fixed Having the valve pocket of tubular, valve rod is slidably matched through valve pocket and with valve pocket composition, described valve pocket is axially arranged with along valve pocket and runs through valve The runner of set, the outlet of described flow passage buffer solution and hydraulic cavities;One end of the close buffer solution outlet of described valve rod i.e. seals End is provided with closure sealing head at described limiting section, and the other end of valve rod i.e. positive stop end is through described valve pocket and towards hydraulic pressure Side, chamber extends, and the positive stop end of valve rod is provided with and makes valve rod keep closure reset assembly at limiting section;
Described liquid feed valve group also includes the valve seat being fixedly installed in gland, the valve pocket being admittedly arranged on valve seat, is interspersed in Valve rod in valve pocket;In liquid feed valve group, valve seat, valve pocket and valve rod are the most corresponding with the structure of valve seat, valve pocket and valve rod in liquid valve group Identical, in liquid feed valve group the sealing head of valve rod be positioned at valve rod towards hydraulic cavities one end, the positive stop end of valve rod in liquid feed valve group Be positioned at valve rod towards buffer inlet one end.
Further, described reset assembly includes back-moving spring and positioning element;Described positioning element is installed in valve rod Away from the end of the first end of seal bar, described back-moving spring is sheathed on valve rod, and one end of back-moving spring is solid with positioning element Fixed connection, the other end of back-moving spring is fixedly connected with valve pocket.
Further, one end matched with sealing head of described valve seat limiting section is in the ring to valve seat inner inclination Planar, described sealing head is then in being easy to the conical surface shape that fits with the anchor ring of described limiting section.
The beneficial effects of the present invention is:
1), the present invention opposite side of piston is provided with dummy piston bar, dummy piston bar stretch out the one end at the pump housing Then being provided with hydraulic buffering mechanism, described dummy piston bar and hydraulic buffering mechanism collectively form flow equilibrium device.Dummy piston The setting of bar, decreases the cylinder difference in volume between two pump chambers of the pump housing, when the shaft diameter of dummy piston bar Yu main piston rod Time equal, the operation of the pump housing is up to optimum operating condition.The use of flow equilibrium device, is possible not only to effectively increase plunger and runs Robustness, flow trim, pulsation when also making pump operation reduce, substantially increase piston pump unit resistance to overturning and Reliability.
2), the hydraulic buffering mechanism in the present invention includes balance set and gland, described dummy piston bar and balance set, gland Jointly enclose hydraulic cavities, when dummy piston bar slides along balance set, suction or extrusion buffer solution in hydraulic cavities, thus increase Big dummy piston bar traveling comfort, further increases resistance to overturning and the reliability of piston pump unit.
3) the liquid in-out valve group, in the present invention is made up of valve seat, valve pocket and valve rod, and the sealed end of valve rod is provided with seal bar Head, the positive stop end of valve rod is provided with reset assembly, owing to reset assembly has certain elastic resistance, therefore decreases buffer solution and enters Going out the speed of hydraulic cavities, so that the opening speed of piston is more uniform, the flow of piston pump is more steady, pulses more flat Weighing apparatus.
4) the described valve seat limiting section, in the present invention is inclined-plane with the face that coordinates of described sealing head, thus decreases and work as Seal and when head resets, seal produced vibration and impact when head contacts with limiting section, improve making of flow equilibrium device Use the life-span.
Accompanying drawing explanation
Fig. 1 is the structural representation of double-acting piston pump in prior art.
Fig. 2 is the structural representation of the present invention.
Fig. 3 is the enlarged diagram of part-structure in Fig. 2.
Fig. 4 is the structural representation of liquid valve group in Fig. 3.
In figure, corresponding to label, each component names is as follows:
10 pump housing 11 feed tube 12 drain pipes
20 main piston rod 30 piston 40 dummy piston bars
50 balance set 51 hydraulic cavities
60 gland 61 buffer solutions export 62 buffer inlet
70 seal washer 80a liquid valve group 80b liquid feed valve groups
81 valve seat 811 limiting section 812 confined planes
82 valve rods 821 seal head 83 back-moving spring
84 positioning element 85 valve pocket 851 runners
Detailed description of the invention
For ease of understanding, here in connection with Fig. 2~4 to the integral installation distribution assembly of the flow equilibrium device for piston pump and work Make below flow process work to describe:
As shown in Figure 2,3, a kind of flow equilibrium device for piston pump, including the pump housing 10 be arranged in the pump housing 10 Piston 30, one end of main piston rod 20 is affixed with piston 30, and the other end of main piston rod 20 stretches out the outside at the pump housing 10;Described Piston 30 is divided into two pump chambers by internal for the pump housing 10, and two pump chambers are connected with respective feed tube and discharging tube respectively, This device includes dummy piston bar 40, described dummy piston bar 40 and the shaft equal diameters of main piston rod 20, and described balance is lived One end of stopper rod 40 is fixedly installed on the side deviating from main piston rod 20 of piston 30, and the other end of dummy piston bar 40 stretches out The outside of the pump housing 10 constituting with hydraulic buffering mechanism is slidably matched;The axis of described dummy piston bar 40 and main piston rod 20 Dead in line.
Dummy piston bar 40 in the present embodiment is coaxially disposed with main piston rod 20.Dummy piston bar 40 can certainly set Being set to two or more, the axis making these multiple dummy piston bars 40 during installation is parallel with the axis of main piston rod 20.
As Fig. 2,3, described hydraulic buffering mechanism includes the balance set 50 with tubular inner chamber and gland 60, and described balance is lived Stretching out in the tubular inner chamber 51 of one end insertion balance set 50 outside the pump housing 10 and constituting with balance set 50 of stopper rod 40 is slided Coordinating, described gland 60 envelope is located at the other end of the far from equilibrium piston rod 40 of balance set 50, described dummy piston bar 40, balance Set 50 and gland 60 enclose hydraulic cavities 51 jointly;Described gland 60 is provided with buffer solution outlet 61 and buffer inlet 62;Institute State hydraulic buffering mechanism and also include that connecting buffer solution exports liquid valve group 80a of 61 and hydraulic cavities 51 and connect buffer inlet 62 and liquid feed valve group 80b of hydraulic cavities 51.
As it is shown on figure 3, be provided with seal washer 70 between described balance set 50 and gland 60, the setting of seal washer 70 guarantees The sealing of flow equilibrium apparatus structure and stability.
The structure of liquid feed valve group 80b and liquid valve group 80a is identical, carries out below in detail as a example by liquid valve group 80a Introduce:
As shown in Figure 3,4, described liquid valve group 80a includes the valve seat 81 being fixedly installed in gland 60;Described valve seat 81 In tubular, the close buffer solution of valve seat 81 exports the internal face inwardly protruding formation limiting section 811 of 61 sides, described limiting section The side towards hydraulic cavities 51 of 811 is installed with the valve pocket 85 of tubular, and valve rod 82 constitutes slip through valve pocket 85 and with valve pocket 85 Coordinating, described valve pocket 85 is axially arranged with along valve pocket the runner 851 running through valve pocket, described runner 851 connects buffer solution outlet 61 With hydraulic cavities 51;One end i.e. sealed end of the close buffer solution outlet 61 of described valve rod 82 is provided with closure at described limiting section 811 The sealing head 821 at place, the other end of valve rod 82 i.e. positive stop end extends through described valve pocket 85 and towards hydraulic cavities 51 side, valve The positive stop end of bar 82 is provided with and makes valve rod 82 keep closure reset assembly at limiting section 811;Described reset assembly includes multiple Position spring 83 and positioning element 84;Described positioning element 84 is installed in the end away from sealing head 821 one end of valve rod 82, Described back-moving spring 83 is sheathed on valve rod 82, and one end of back-moving spring 83 is fixedly connected with positioning element 84, back-moving spring 83 The other end be fixedly connected with valve pocket 85.
Described liquid feed valve group 80b also includes the valve seat being fixedly installed in gland, the valve pocket being admittedly arranged on valve seat, interts Valve rod in valve pocket;Valve seat, valve pocket and valve rod and valve seat, valve pocket and the knot of valve rod in liquid valve group 80a in liquid feed valve group 80b Structure is the most corresponding identical, as it is shown on figure 3, in liquid feed valve group 80b the sealing head of valve rod be positioned at valve rod towards hydraulic cavities one end, enter In liquid valve group 80b the positive stop end of valve rod be positioned at valve rod towards buffer inlet 62 one end.
As shown in Figure 4, one end matched with sealing head 821 of described limiting section 811 is in valve seat inner inclination Anchor ring shape, this anchor ring is the confined planes 812 shown in Fig. 4, and described sealing head 821 is then in being easy to and described limiting section 811 The conical surface shape that fits of confined planes 812.
The course of work of 2 couples of present invention elaborates below in conjunction with the accompanying drawings:
During work, as in figure 2 it is shown, when main piston rod 20 drive piston 30 along dotted arrow to left movement time, balance live Stopper rod 40 is followed piston 30 and is moved to the left, and now on the left of the pump housing 10, the medium in pump chamber that is 1 chamber is discharged, now liquid feed valve group 80b opens and liquid valve group 80a is closed, and buffer solution is slowly entered hydraulic cavities 51 by liquid feed valve group 80b;When main piston rod 20 drives Piston 30 along dotted arrow move right time, dummy piston bar 40 follows piston 30 and moves right, now pump on the right side of the pump housing 10 Medium in chamber, chamber that is 2 is discharged, now liquid feed valve group 80b close and liquid valve group 80a is opened, buffer solution is by liquid valve group 80a slowly discharges hydraulic cavities 51.
Comparing piston pump more of the prior art, the opening speed of the piston in the present invention is more uniform, and flow is more flat Surely, pulsation more balances, and improves the reliability and stability of piston pump work.

Claims (5)

1. for the flow equilibrium device of piston pump, including the pump housing (10) and the piston (30) that is arranged in the pump housing (10), One end of main piston rod (20) is affixed with piston (30), and the other end of main piston rod (20) stretches out the outside in the pump housing (10);Institute State piston (30) and be divided into two pump chambers by internal for the pump housing (10), two pump chambers respectively with respective feed tube and discharging tube phase Connection, it is characterised in that: this device includes that dummy piston bar (40), one end of described dummy piston bar (40) are fixedly installed on work Plug (30) the side deviating from main piston rod (20), the other end of dummy piston bar (40) stretch out the outside of the pump housing (10) and with Hydraulic buffering mechanism composition is slidably matched;The axis of described dummy piston bar (40) is parallel with the axis of main piston rod (20) or heavy Close;
Described hydraulic buffering mechanism includes the balance set (50) with tubular inner chamber and gland (60), described dummy piston bar (40) Stretch out in the tubular inner chamber (51) of balance set (50) is inserted in the one end in the pump housing (10) outside and constitute sliding with balance set (50) Dynamic cooperation, described gland (60) envelope is located at the other end of the far from equilibrium piston rod (40) of balance set (50), described dummy piston Bar (40), balance set (50) and gland (60) enclose hydraulic cavities (51) jointly;Described gland (60) is provided with buffer solution outlet And buffer inlet (62) (61);Described hydraulic buffering mechanism also includes connecting going out of buffer solution outlet (61) and hydraulic cavities (51) Liquid valve group (80a) and connection buffer inlet (62) and the liquid feed valve group (80b) of hydraulic cavities (51);
Described liquid valve group (80a) includes the valve seat (81) being fixedly installed in gland (60);Described valve seat (81) in tubular, valve The internal face inwardly protruding formation limiting section (811) of close buffer solution outlet (61) side of seat (81), described limiting section (811) The side towards hydraulic cavities (51) be installed with the valve pocket (85) of tubular, valve rod (82) through valve pocket (85) and with valve pocket (85) structure One-tenth is slidably matched, and described valve pocket (85) is axially arranged with the runner (851) running through valve pocket along valve pocket, and described runner (851) connects Buffer solution outlet (61) and hydraulic cavities (51);One end i.e. sealed end of close buffer solution outlet (61) of described valve rod (82) is provided with The closure sealing head (821) at described limiting section (811) place, the other end i.e. positive stop end of valve rod (82) passes described valve pocket (85) and towards hydraulic cavities (51) side extending, the positive stop end of valve rod (82) is provided with and makes valve rod (82) keep closure at limiting section (811) reset assembly at place;
Described liquid feed valve group (80b) also includes the valve seat being fixedly installed in gland, the valve pocket being admittedly arranged on valve seat, is interspersed in Valve rod in valve pocket;Valve seat, valve pocket and valve rod and valve seat, valve pocket and valve rod in liquid valve group (80a) in liquid feed valve group (80b) Structure is the most corresponding identical, in liquid feed valve group (80b) the sealing head of valve rod be positioned at valve rod towards hydraulic cavities one end, liquid feed valve group (80b) in the positive stop end of valve rod be positioned at valve rod towards buffer inlet (62) one end.
Flow equilibrium apparatus structure for piston pump the most according to claim 1, it is characterised in that: described dummy piston Bar (40) and the shaft equal diameters of main piston rod (20).
Flow equilibrium apparatus structure for piston pump the most according to claim 1, it is characterised in that: described balance set And between gland (60), be provided with seal washer (70) (50).
Flow equilibrium apparatus structure for piston pump the most according to claim 1, it is characterised in that: described reset assembly Including back-moving spring (83) and positioning element (84);Described positioning element (84) be installed in valve rod (82) away from seal head (821) end of one end, described back-moving spring (83) is sheathed on valve rod (82), one end of back-moving spring (83) and location division Part (84) is fixedly connected, and the other end of back-moving spring (83) is fixedly connected with valve pocket (85).
Flow equilibrium apparatus structure for piston pump the most according to claim 4, it is characterised in that: described limiting section (811) one end matched with sealing head (821) is in the anchor ring shape of valve seat inner inclination, described sealing head (821) Then in being easy to the conical surface shape that fits with the anchor ring of described limiting section (811).
CN201410604996.7A 2014-10-30 2014-10-30 A kind of flow equilibrium device for piston pump Active CN104358684B (en)

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CN104358684B true CN104358684B (en) 2016-08-24

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CN111502957A (en) * 2020-05-21 2020-08-07 安慕科技(深圳)有限公司 One-pump multi-head air outlet pump
CN115681124A (en) * 2021-11-26 2023-02-03 深圳华星恒泰泵阀有限公司 Leak-proof anti-loosening structure and corresponding electromagnetic pump
CN117419026B (en) * 2023-11-10 2024-03-08 欧技工业设备(江苏)有限公司 Liquid flow pump with depressurization sealing structure

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Publication number Priority date Publication date Assignee Title
CN1124824A (en) * 1994-12-13 1996-06-19 胡俊威 Reciprocating piston reversible recovery delivery pump
US5605446A (en) * 1994-10-18 1997-02-25 Graco Inc. High viscosity material pump having valved priming piston
CN101372913A (en) * 2007-08-21 2009-02-25 清华大学深圳研究生院 Double group component hydraulic free-piston engine
CN202040296U (en) * 2011-05-17 2011-11-16 侯亚峰 Power transmission and hydraulic stepless speed change device
CN102619743A (en) * 2012-04-17 2012-08-01 三一重工股份有限公司 Distributing valve, pumping system and engineering machinery
CN103291664A (en) * 2013-06-06 2013-09-11 王健 Hydraulic buffering driving and buffering braking device
CN204253354U (en) * 2014-10-30 2015-04-08 合肥工业大学 A kind of flow equilibrium device for reciprocating pump

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5605446A (en) * 1994-10-18 1997-02-25 Graco Inc. High viscosity material pump having valved priming piston
CN1124824A (en) * 1994-12-13 1996-06-19 胡俊威 Reciprocating piston reversible recovery delivery pump
CN101372913A (en) * 2007-08-21 2009-02-25 清华大学深圳研究生院 Double group component hydraulic free-piston engine
CN202040296U (en) * 2011-05-17 2011-11-16 侯亚峰 Power transmission and hydraulic stepless speed change device
CN102619743A (en) * 2012-04-17 2012-08-01 三一重工股份有限公司 Distributing valve, pumping system and engineering machinery
CN103291664A (en) * 2013-06-06 2013-09-11 王健 Hydraulic buffering driving and buffering braking device
CN204253354U (en) * 2014-10-30 2015-04-08 合肥工业大学 A kind of flow equilibrium device for reciprocating pump

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