CN201461569U - Hydraulic balance valve - Google Patents

Hydraulic balance valve Download PDF

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Publication number
CN201461569U
CN201461569U CN2009200726412U CN200920072641U CN201461569U CN 201461569 U CN201461569 U CN 201461569U CN 2009200726412 U CN2009200726412 U CN 2009200726412U CN 200920072641 U CN200920072641 U CN 200920072641U CN 201461569 U CN201461569 U CN 201461569U
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CN
China
Prior art keywords
valve
main valve
guide
main
spool
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
Application number
CN2009200726412U
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Chinese (zh)
Inventor
袁才富
刘峰伟
朱剑根
陈长信
张坚
米根祥
沈至伟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Lixin Hydraulic Co Ltd
Original Assignee
Shanghai Lixin Hydraulic Co Ltd
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
Application filed by Shanghai Lixin Hydraulic Co Ltd filed Critical Shanghai Lixin Hydraulic Co Ltd
Priority to CN2009200726412U priority Critical patent/CN201461569U/en
Application granted granted Critical
Publication of CN201461569U publication Critical patent/CN201461569U/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Abstract

The utility model relates to a hydraulic balance valve which comprises a main valve and a pilot valve, wherein a main valve hole of the pilot valve is internally provided with a push rod seat, and a small radial hole is arranged on the push rod seat; the push rod seat is internally provided with an axial hole, and the axial hole is internally provided with a first steel ball; a pressure adjusting spring is arranged between the first steel ball and the push rod seat, and the right end face of the push rod seat is provided with a small axial hole; one end of a push rod passes through the small axial hole and then is butted against the first steel ball, while the other end is inserted in a blind hole on the left end face of a control valve element; the control valve element is arranged in the body of the main valve; and an ejector rod at the right end of the control valve element extends into a main valve element and is opposite to a pilot valve element. The utility model has the advantages that the response time of the control valve element can be adjusted so as to change the open speed of a main valve port and effectively control the flow amount of hydraulic oil, and a suspension arm cannot shake during working when a heavy object is descended.

Description

Hydraulically balanced valve
Technical field
The utility model relates to the valve assembly that a kind of hydraulic pressure installation is used, and relates in particular to a kind of hydraulically balanced valve that can keep load steadily to transfer.
Background technique
In machinery such as the engineering machinery in modern times, building machinery, widely applied the hydraulic pressure load bearing system, wherein equilibrium valve is the crucial hydraulic element of this type systematic, the quality of its performance directly affects machine performance.The such shortcoming of existing hydraulically balanced valve ubiquity: when load is transferred, because the valve core opening of hydraulically balanced valve is difficult to be stabilized on the definite openings of sizes, make load produce the phenomenon of low-frequency jitter, cause system's instability, influence the safety reliability of complete machine.
For head it off, damping hole has all been set up in a lot of new equilibrium valve inside, the low-frequency jitter when eliminating load and transfer with this, and the shortcoming of this method is: the response time of influence control spool.
The model utility content
Technical problem to be solved in the utility model is, the defective that overcomes prior art provides a kind of and operate steadily, control the adjustable hydraulically balanced valve of response time of spool.
To achieve these goals, the technical solution of the utility model is as follows:
Hydraulically balanced valve, comprise main valve and pilot valve, the valve body of main valve of described main valve is provided with main valve chamber, guide's valve pocket, the aperture that connects main valve chamber and guide's valve pocket, and A mouth that is connected with main valve chamber and B mouth, be provided with main valve plug in the main valve chamber, guide's spool is arranged in the main valve plug, the control spool of pilot valve is installed in guide's valve pocket, the push rod of control spool right-hand member pass stretch in the main valve plug behind the described aperture relative with guide's spool, control mouthful X is arranged on guide's valve body of pilot valve, it is characterized in that, be provided with ram seat in guide's valve body main aperture of described pilot valve, have radial hole on the ram seat, ram seat inside has axial bore, is placed with first steel ball in this axial bore, between first steel ball and ram seat pressure adjusting spring is arranged, the right side of ram seat has axial aperture, one end of one push rod withstands on first steel ball after passing this axial aperture, and the other end is inserted in the blind hole of control spool left side, and the diameter of this push rod is slightly less than the diameter of described axial aperture; Also offer porosely on the left side of control spool, this hole is communicated with the left and right cavity volume of control spool, is provided with pressure check valve in the hole; Also have the leakage hydraulic fluid port that is connected with guide's valve pocket on the described valve body of main valve.
Further, in the utility model, described main valve plug is bar shape, on the middle cylinder of main valve plug, be evenly distributed in the dark right shallow some axial wedge slot in a left side, on main valve plug right-hand member cylinder, have axial throttling groove and main valve plug radial hole from right to left successively, main valve plug inside is provided with guide's spool cavity volume, is used to place guide's spool.
Further, in the utility model, the centre of described ram seat has between one section outer wall and the valve body of main valve inner wall of main hole gapped, also has passage on described guide's valve body, described gap of channel connection and control spool left cavity are provided with second damper and the 3rd damper in the described passage.
Further, in the utility model, the left side of described control spool is a sphere.
Further, in the utility model, described ram seat is threaded in guide's valve body main aperture.
Further, in the utility model, have radially shoulder hole of spring seat on the spring seat of described main valve plug, spring seat radially shoulder hole is communicated with the B mouth of guide's spool right cavity and valve body of main valve, and this spring seat radially is placed with second steel ball on the ladder of shoulder hole.
Advantage of the present utility model is:
1, owing to adopts between ram seat and the guide's valve body and is threaded, the position of ram seat in the pilot valve body can be regulated, when ram seat turns clockwise, make control spool left cavity volume diminish, accelerated the response time of control spool this moment, on the contrary the response time of the control spool that then slowed down.Thereby can control the opening speed of primary valve, control the hydraulic oil flow momentum effectively, weight jitter phenomenon can not occur when descending; Strengthened Security, made action more reliable.
2, be provided with some damping holes in the valve body of main valve, eliminated the low-frequency jitter in the decline weight process, strengthened Security, make action more reliable, and in the load uphill process, energy loss is less, the efficient height.
3, under the situation of the damaged decompression of flexible pipe, can prevent that load stall from descending, can play the effect of a hydraulic lock, protection oil cylinder or hydraulic system are not damaged.
4, valve body structure and processing technology are simple, are convenient to mounting or dismounting and maintenance, and manufacture cost is lower.
The utility model can be used for the hydraulic pressure load bearing system of engineering machinery such as truck crane, automobile truck-mounted crane, large-scale or telescopic fork truck, municipal machinery, forestry machinery.
Description of drawings
Describe the utility model in detail below in conjunction with the drawings and specific embodiments:
Fig. 1 is a cross-sectional view of the present utility model;
Fig. 2 is that the C of Fig. 1 is to the part section structural representation;
Fig. 3 is the cross-sectional view of valve body of main valve of the present utility model;
Fig. 4 is the structural representation of main valve plug of the present utility model;
Fig. 5 is the cross-sectional view of Fig. 4;
Fig. 6 be among Fig. 4 D-D to cross-sectional view;
Fig. 7 is the structural representation of the main valve plug of 200L/min for flow;
Fig. 8 be among Fig. 7 E-E to cross-sectional view;
Fig. 9 is the structural representation of the main valve plug of 300L/min for flow;
Figure 10 be among Fig. 9 F-F to cross-sectional view;
Figure 11 is the structural representation of control spool of the present utility model;
Figure 12 is the structural representation of ram seat of the present utility model;
Figure 13 is a schematic diagram of the present utility model.
Embodiment
For technological means, creation characteristic that the utility model is realized, reach purpose and effect is easy to understand, below in conjunction with concrete diagram, further set forth the utility model.
Referring to Fig. 1,2, a kind of equilibrium valve is made up of main valve and pilot valve, and pilot valve is installed on the main valve.
Referring to Fig. 3, the front surface of valve body of main valve 43 and rear surface process inclined hole A and A1 hydraulic fluid port (as shown in Figure 2) respectively, at valve body of main valve bottom surface machining B mouth, stepped main valve chamber 45, the three hydraulic fluid port A of the right part machining of valve body of main valve 43, A1, B communicate with main valve chamber 45 respectively.The left part machining guide valve pocket 44 of valve body of main valve 43 is used to install the control spool of pilot valve, is connected by Φ 4 apertures between guide's valve pocket and the main valve chamber.On the pilot valve chamber, be provided with and leak hydraulic fluid port L, leak between hydraulic fluid port L and the guide's valve pocket and be communicated with by controlling oily leakage.
Refer again to Fig. 1, valve pocket 26 is arranged in the main valve chamber of valve body of main valve 43, valve pocket 26 is tube structure, makes valve pocket aperture 40 on its circumference side, makes groove at the left end cylindrical place of valve pocket 26, is used to place seal ring and back-up ring, prevents the hydraulic oil internal leakage.The right of valve pocket 26 is the blind nut 34 that has shoulder, and blind nut 34 is threaded with main valve chamber, and there is groove the shoulder of blind nut 34 and screw thread jointing place, are used to place seal ring, prevent the hydraulic oil external leakage.Get out an oilhole at the center of blind nut 34, plug screw 35 can be assembled in right-hand member tap out hole, this plug screw 35 of dismantling, and tapped hole just can be used as the pressure tap MB of B mouth.
Blind nut 34 is embedded with the spring seat 32 of band Steel Cable Baffle Ring, between blind nut 34 and the spring seat 32 butterfly spring is arranged.Make the axial step hole at the left end of spring seat 32, be used to place spring, right-hand member at spring seat 32 has spring seat passage 33, and this spring seat passage 33 and spring seat radially cavity volume 38 (gap between spring seat outer wall and the blind nut inwall) connect mutually, play the effect of throttling.Spring seat 32 is made radially shoulder hole of spring seat on the circumference side in addition, and spring seat radially shoulder hole is communicated with the B mouth of guide's spool right cavity 31 and valve body of main valve, and this spring seat radially is placed with second steel ball 36 on the ladder of shoulder hole.The left end external diameter of spring seat 32 matches with valve pocket 26 right-hand member step holes, and spring seat 32 left sides are pressed on the counterbore step of valve pocket 26 right-hand members.Be placed with first main spool spring 37 in the axial step hole of spring seat 32, the other end of main spool spring 37 withstands on the right-hand member of guide's spool 25.
Main valve plug 24 is installed in the valve pocket 26, and referring to Fig. 4,5,6, main valve plug 24 is bar shape substantially, and the surface is provided with the circular step that matches with valve pocket and constitutes primary sealing area 42.On the middle cylinder of main valve plug 24, be evenly distributed in dark right six the shallow axial wedge slots 46 in a left side, on main valve plug right-hand member cylinder, have axial throttling groove 30 and main valve plug radial hole 29 from right to left successively.Have guide's spool cavity volume in the main valve plug 24, be used to place guide's spool.Fig. 4 is the main valve plug of 100L/min for flow, certainly, the angle of above-mentioned wedge slot, length and quantity can change according to the size of actual flow, shown in Fig. 7,8, the flow of this main valve plug is 200L/min, and Fig. 9,10 is depicted as the main valve plug that flow is 300L/min.
Guide's spool 25 is equipped with in main valve plug 24 inside, it is cylindrical that guide's spool 25 is roughly ladder, the surface is provided with the conical surface that matches with main valve plug and constitutes secondary sealing area 27, have the pilot valve mandrel to endoporus 39 in the right-hand member cylinder of guide's spool 25, also have the pilot valve core diameter on guide's spool 25 to aperture 28, the pilot valve core diameter is communicated with the pilot valve mandrel to endoporus 39 and guide's spool left cavity 41 to aperture 28, the left end cylinder of guide's spool 25 extend into the through hole of guide's spool cavity volume bottom centre, and relative with the push rod of control spool 21.
Be connected by bolt between guide's valve body 17 of pilot valve and the valve body of main valve 43, the control spool 21 of pilot valve is installed in guide's valve pocket 44.Guide's valve body 17 inside have axial guide's valve body main aperture, on the pilot valve body, have radial screw bore, this radial screw bore internal thread connects a connecting sleeve 13, and the top of connecting sleeve 13 is equipped with joint 15 and is constituted control mouthful X, so that be connected with the control mouth of oil hydraulic motor.In the bottom of connecting sleeve first damper 12 is housed, is provided with filter screen 14 between joint 15 and the connecting sleeve 13, can filter the impurity in the fluid.
Guide's valve body main aperture internal thread connects the ram seat 9 of a cylindricality, and referring to Figure 12, ram seat 9 left ends stretch out outside guide's valve body 17, and its outside is with locking nut 8 and nut 10.The centre of ram seat 9 has between one section outer wall and the valve body of main valve inner wall of main hole gapped 18, on this section outer wall, have radial hole 4, have axial bore 19 in ram seat inside, be placed with first steel ball 5 in this axial bore 19, between first steel ball 5 and ram seat 9, pressure adjusting spring 11 is arranged, the right side of ram seat 9 has axial aperture 48, one end of one push rod 20 withstands on first steel ball 5 after passing this axial aperture 48, the other end is inserted in the blind hole of control spool 21 left sides, and the diameter of this push rod 20 is slightly less than the diameter of above-mentioned axial aperture 48.
Also have passage 6 on guide's valve body 17, passage 6 communication gap 18 (gapped between ram seat and the valve body of main valve inner wall of main hole) and control spool left cavity 16 are provided with second damper 7 and the 3rd damper 3 in this passage 6.
Control spool 21 is arranged in guide's valve pocket 44 of valve body of main valve, referring to Figure 11, control spool 21 is the multidiameter shaft shape, its maximum level outer circumferential walls cooperates with the inwall of guide's valve pocket. in pilot valve chamber 44, place pilot valve spring 22, one end of pilot valve spring 22 is positioned at the step place of guide's valve pocket, the other end is positioned on the step of control spool 21. control spool 21 front ends have one section push rod that diameter is thinner, this push rod pass stretch into behind Φ 4 apertures in the main valve plug relative with above-mentioned guide's spool 25. the left side of controlling spool 21 is not plane but a sphere that concaves.
Have a blind hole in the middle of the left side of control spool, push rod 20 is inserted in this blind hole.Also offer porosely 47 on the left side of control spool, this hole 47 is communicated with control left and right cavity volumes of spool (16,23), is placed with the 4th damper 2 in the hole 47 and the 3rd steel ball 1 constitutes pressure check valve.
When the control left and right cavity volume of spool (16,23) produces pressure reduction, control spool 21 is moved right slowly, this moment, first steel ball 5 was also along with moving, until the step place that withstands on ram seat 9 low order ends.This moment first steel ball 5 unidirectional closed conditions, the fluid that control this moment mouthful X enters has only by second damper 7, the 3rd damper 3 and enters control spool left cavity 21, until making control spool 21 be pushed into the interior hole end surface of guide's valve pocket 44.
It is to be noted, be threaded owing to adopt between ram seat and the guide's valve body, the position of ram seat in the pilot valve body can be regulated, when ram seat turns clockwise, make control spool left cavity volume diminish, accelerated the response time of control spool this moment, on the contrary the response time of the control spool that then slowed down.Thereby can control the opening speed of primary valve, control the hydraulic oil flow momentum effectively, weight jitter phenomenon can not occur when descending; Strengthened Security, made action more reliable.
The working procedure of this equilibrium valve is as follows:
(1) load (A → B) that hoists
After pressure oil entered from the A mouth, along with the increase of pressure, pressure oil overcame the pretightening force of main spool spring 37, promotes main valve plug 24 to the right, and pressure oil directly enters the B chamber from the wedge slot 46 of main valve plug then; And the fluid of guide's spool right cavity 31, a part enters the B chamber by the axial throttling groove 30 on the main valve plug, another part under pressure, push second steel ball 36 open, by spring seat radially cavity volume 38 flow into the B chambeies, so just eliminated the back pressure of main valve plug 24, accelerated to open the opening speed of main valve plug 24, when main valve plug 24 came to spring seat 32, this moment, A reached maximum by the B flow.In the whole process, pilot valve is inoperative.
If the high pressure hose that is connected with the A mouth breaks suddenly, cause A mouth instantaneous loss of pressure, this moment, protection oil cylinder or hydraulic system were not damaged because guide's spool right cavity 31 is leading to induced pressure, and main valve plug 24 is closed immediately.
(2) (B → A) is transferred in load
Control mouthful X oil-feed, fluid is through filter screen 14, first damper 12, enter control spool left cavity 16 by the radial hole 4 of ram seat, the axial aperture 48 and the gap between the push rod 20 of ram seat again, part fluid is pushed the 3rd steel ball 1 inflow control valve core right cavity 23 open by the 4th damper 2, and then, make between the left and right cavity volume of controlling spool 21 and produce pressure reduction by controlling the oil leakage passage from leaking the outflow of hydraulic fluid port L mouth.Along with the increase of pressure, pressure oil overcomes the pretightening force of pilot valve spring 22 and main spool spring 37, promotes control spool 21 to the right, makes guide's spool 25 lift away from main valve plug 24, and the secondary sealing area 27 between main valve plug 24 and the guide's spool 25 is opened at this moment; The fluid that the B mouth enters enters guide's spool right cavity 31 by the axial throttling groove 30 of main valve plug radial hole 29 or main valve plug, and fluid flows into A mouth to endoporus 39, pilot valve core diameter to aperture 28, secondary sealing area through the pilot valve mandrel again.Along with guide's spool 25 continues toward moving to right, after guide valve core 25 is closed main valve plug radial hole 29 in the ban, the pressure of guide's spool right cavity 31 descends gradually, decline along with pressure, the fluid in the A chamber that has flowed into forces main valve plug 24 integral body to move right, and the fluid that this moment, the B mouth entered enters the A mouth from the wedge slot 46 on the main valve plug, the valve port standard-sized sheet, move to low order end until main valve plug 24, the flow that B enters A reaches maximum.
More than showing and described basic principle of the present utility model, major character and advantage of the present utility model. the technician of the industry should understand; the utility model is not restricted to the described embodiments; what describe in the foregoing description and the specification is principle of the present utility model; the utility model also has various changes and modifications under the prerequisite that does not break away from the utility model spirit and scope, and these changes and improvements all fall in the claimed scope of the present utility model. and the protection domain that the utility model requires is defined by appending claims and equivalent thereof.

Claims (6)

1. hydraulically balanced valve, comprise main valve and pilot valve, the valve body of main valve of described main valve is provided with main valve chamber, guide's valve pocket, the aperture that connects main valve chamber and guide's valve pocket, and A mouth that is connected with main valve chamber and B mouth, be provided with main valve plug in the main valve chamber, guide's spool is arranged in the main valve plug, the control spool of pilot valve is installed in guide's valve pocket, the push rod of control spool right-hand member pass stretch in the main valve plug behind the described aperture relative with guide's spool, control mouthful X is arranged on guide's valve body of pilot valve, it is characterized in that, be provided with ram seat in guide's valve body main aperture of described pilot valve, have radial hole on the ram seat, ram seat inside has axial bore, is placed with first steel ball in this axial bore, between first steel ball and ram seat pressure adjusting spring is arranged, the right side of ram seat has axial aperture, one end of one push rod withstands on first steel ball after passing this axial aperture, and the other end is inserted in the blind hole of control spool left side, and the diameter of this push rod is slightly less than the diameter of described axial aperture; Also offer porosely on the left side of control spool, this hole is communicated with the left and right cavity volume of control spool, is provided with pressure check valve in the hole; Also have the leakage hydraulic fluid port that is connected with guide's valve pocket on the described valve body of main valve.
2. hydraulically balanced valve according to claim 1, it is characterized in that, described main valve plug is bar shape, on the middle cylinder of main valve plug, be evenly distributed in the dark right shallow some axial wedge slot in a left side, have axial throttling groove and main valve plug radial hole on main valve plug right-hand member cylinder from right to left successively, main valve plug inside is provided with guide's spool cavity volume.
3. hydraulically balanced valve according to claim 1, it is characterized in that, the centre of described ram seat has between one section outer wall and the valve body of main valve inner wall of main hole gapped, also have passage on described guide's valve body, described gap of channel connection and control spool left cavity are provided with second damper and the 3rd damper in the described passage.
4. hydraulically balanced valve according to claim 1 is characterized in that, the left side of described control spool is a sphere.
5. hydraulically balanced valve according to claim 1 is characterized in that, described ram seat is threaded in guide's valve body main aperture.
6. hydraulically balanced valve according to claim 1, it is characterized in that, have radially shoulder hole of spring seat on the spring seat of described main valve plug, spring seat radially shoulder hole is communicated with the B mouth of guide's spool right cavity and valve body of main valve, and this spring seat radially is placed with second steel ball on the ladder of shoulder hole.
CN2009200726412U 2009-05-21 2009-05-21 Hydraulic balance valve Expired - Lifetime CN201461569U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2009200726412U CN201461569U (en) 2009-05-21 2009-05-21 Hydraulic balance valve

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Application Number Priority Date Filing Date Title
CN2009200726412U CN201461569U (en) 2009-05-21 2009-05-21 Hydraulic balance valve

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CN201461569U true CN201461569U (en) 2010-05-12

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CN2009200726412U Expired - Lifetime CN201461569U (en) 2009-05-21 2009-05-21 Hydraulic balance valve

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102072215A (en) * 2011-02-02 2011-05-25 卢宇 Balance valve with quickly-closing valve plug
CN102536943A (en) * 2012-02-24 2012-07-04 徐州重型机械有限公司 Balance valve as well as winch system and crane provided with same
CN101893010B (en) * 2009-05-21 2013-02-13 上海立新液压有限公司 Hydraulic balanced valve
CN103104565A (en) * 2012-12-13 2013-05-15 陈磊 Balance valve
CN108757615A (en) * 2018-06-28 2018-11-06 徐工集团工程机械有限公司 Balanced valve, hydraulic system and engineering machinery

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101893010B (en) * 2009-05-21 2013-02-13 上海立新液压有限公司 Hydraulic balanced valve
CN102072215A (en) * 2011-02-02 2011-05-25 卢宇 Balance valve with quickly-closing valve plug
CN102072215B (en) * 2011-02-02 2012-11-28 卢宇 Balance valve with quickly-closing valve plug
CN102536943A (en) * 2012-02-24 2012-07-04 徐州重型机械有限公司 Balance valve as well as winch system and crane provided with same
CN102536943B (en) * 2012-02-24 2015-06-17 徐州重型机械有限公司 Balance valve as well as winch system and crane provided with same
CN103104565A (en) * 2012-12-13 2013-05-15 陈磊 Balance valve
CN108757615A (en) * 2018-06-28 2018-11-06 徐工集团工程机械有限公司 Balanced valve, hydraulic system and engineering machinery
CN108757615B (en) * 2018-06-28 2020-07-07 徐工集团工程机械有限公司 Balance valve, hydraulic system and engineering machinery

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C14 Grant of patent or utility model
GR01 Patent grant
AV01 Patent right actively abandoned

Granted publication date: 20100512

Effective date of abandoning: 20090521

RGAV Abandon patent right to avoid regrant