CN103953370A - Nitrogen safety valve used by coalmine fully-mechanized mining hydraulic bracket - Google Patents
Nitrogen safety valve used by coalmine fully-mechanized mining hydraulic bracket Download PDFInfo
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- CN103953370A CN103953370A CN201410197673.0A CN201410197673A CN103953370A CN 103953370 A CN103953370 A CN 103953370A CN 201410197673 A CN201410197673 A CN 201410197673A CN 103953370 A CN103953370 A CN 103953370A
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- valve
- swivel nut
- valve casing
- nitrogen
- storing cavity
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Abstract
The invention discloses a nitrogen safety valve used by a coalmine fully-mechanized mining hydraulic bracket. The nitrogen safety valve comprises a valve casing and a valve core, wherein the valve core is internally formed in a valve hole of the valve casing, unloading holes are formed in the outer walls of the valve core and the valve casing, one end of the valve casing is connected with an oil cylinder of the hydraulic bracket, the other end of the valve casing is connected with one end of a threaded sleeve, the other end of the threaded sleeve is closed, an oil inlet is formed in the valve casing, a gas storage cavity is formed in the threaded sleeve, nitrogen is stored in the gas storage cavity, the valve hole and the oil inlet are communicated with the gas storage cavity, and the valve core in the valve hole is reset under the action of the nitrogen in the gas storage cavity. Compared with the prior art, the nitrogen safety valve has the advantages that the properties of the nitrogen are fully utilized through the arrangement of the gas storage cavity storing the nitrogen on the safety valve, the safety valve is used in a wider range of pressure than a mode of adopting a spring in resetting, super-high pressure can be bore, the spring force is constant, and the size is small.
Description
Technical field
The present invention relates to coal mine fully-mechanized mining hydraulic support, specifically, the present invention relates to a kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket.
Background technology
Large-scale enforcement and development along with coal mine fully-mechanized mining hydraulic support; working face is also more and more stricter to the requirement of hydraulic support; so just the safety valve of protective cradle hydraulic jack has been had to further requirement; especially to the application life of the high-flow safety valve using on hydraulic support and reliability having had further requirement; when the pressure from hydraulic support top causes by power; can safety valve in the situation that bearing high pressure, and the short time, in time abundant stable off-load directly affected application life and the supporting safety of support.It not only can damage seal, pipeline and Hydraulic Elements, but also can cause vibrations and noise; Sometimes make some pressure controlled Hydraulic Elements produce error.The structure of the safety valve using at present as shown in Figure 2, it comprises valve body 14, spool 2, valve casing 1 and be built in the spring in valve casing 1, on valve casing 1 and spool 2, there is unloading hole, when the cylinder force of hydraulic support surpasses the pressure that spring sets up, spool 2 promotes spring base and moves to afterbody under pressure promotes, when the unloading hole on spool 2 moves past special sealing ring, the unloading hole of hydraulic oil from valve casing 1 discharged, because there is sealing performance reliably spring base and valve casing 1 inside, hydraulic oil does not enter spring working chamber, at this moment the pressure in oil cylinder can reduce along with off-load, when the pressure of oil cylinder is less than the power of spring, safety valve is resetted by spring action, recover sealing state.Safety valve adopts spring to reset, but the pressure-bearing scope of spring is little, and can not bear super-pressure, cause the working pressure scope of safety valve little, the use of safety valve is restricted, in addition, spring takes up room greatly, make the volume of safety valve become large, spring also needs just can reach the elastic force pressure of needs by pretension, and elastic force pressure is non-constant.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket, and this safety valve working pressure scope is wide, can bear super-pressure.
In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is: a kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket, comprise valve casing and spool, described spool is built in the valve opening of described valve casing, on the outer wall of spool and valve casing, be provided with unloading hole, one end of valve casing is connected with the oil cylinder of described hydraulic support, the other end is connected with one end of a swivel nut, the other end sealing of this swivel nut, on valve casing, there is fuel feed hole, in swivel nut, there is air storing cavity, in air storing cavity, store nitrogen, valve opening is communicated with fuel feed hole and air storing cavity, under the effect of the nitrogen in air storing cavity of the spool in valve opening, reset, the end that described valve casing is connected with described swivel nut has the second air storing cavity being communicated with air storing cavity on swivel nut, described valve casing with described swivel nut for being threaded, in described swivel nut, be provided with a limiting plate, the inwall of swivel nut is provided with the step of placing this limiting plate, the end that described valve casing is connected with swivel nut is resisted against on this limiting plate, is also provided with the air storing cavity that is communicated with on described swivel nut and the through hole of the second air storing cavity on limiting plate, the end towards described swivel nut of described spool has the 3rd air storing cavity being communicated with air storing cavity on swivel nut, the end towards described fuel feed hole of described spool has two deep holes that are communicated with fuel feed hole, is respectively equipped with a described unloading hole on each deep hole, between described spool and described valve casing, be provided with O RunddichtringO, between described valve casing and described swivel nut, be provided with O RunddichtringO.
Blind end at described swivel nut is provided with charge valve and screw plug, and screw plug is threaded with swivel nut and covers charge valve.
The present invention adopts technique scheme, compared with prior art, the air storing cavity that stores nitrogen is set on safety valve, make full use of the characteristic of nitrogen, than the mode that adopts spring to reset, safety valve working pressure scope is wide, can bear super-pressure, elastic force pressure is constant, and volume is little.
Accompanying drawing explanation
Fig. 1 is the structural representation of safety valve of the present invention;
Fig. 2 is the structural representation of the safety valve in background technology;
Mark in above-mentioned figure is: 1, valve casing; 2, spool; 3, swivel nut; 4, limiting plate; 5, charge valve; 6, spring; 7, pad; 8, screw plug; 9, O RunddichtringO; 10, O RunddichtringO; 11, O RunddichtringO; 12, O RunddichtringO; 13, O RunddichtringO; 14, valve body; 15, air storing cavity; 16, the second air storing cavity; 17, the 3rd air storing cavity.
The specific embodiment
Be illustrated in figure 1 a kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket of the present invention, the valve casing 1 and the spool 2 that comprise column, function and the structure of valve body that the valve casing 1 of safety valve has safety valve of the prior art is similar, for valve casing and the valve body of prior art integrated.The spool 2 of safety valve is built in the valve opening of valve casing 1, on the outer wall of spool 2 and valve casing 1, be provided with unloading hole, one end of valve casing 1 is connected with the oil cylinder of hydraulic support, and the other end is connected with one end of a swivel nut 3, the other end sealing of this swivel nut 3, swivel nut 3 is column, on valve casing 1, there is fuel feed hole, in swivel nut 3, there is air storing cavity 15, in air storing cavity 15, store nitrogen, valve opening is communicated with fuel feed hole and air storing cavity 15, under the effect of spool 2 nitrogen in air storing cavity 15 in valve opening, resets.Compared with prior art, the air storing cavity 15 that stores nitrogen is set on safety valve, makes full use of the characteristic of nitrogen, than the mode that adopts spring to reset, safety valve working pressure scope is wide, can bear super-pressure, and elastic force pressure is constant, and volume is little.
As shown in Figure 1, the end that valve casing 1 is connected with swivel nut 3 has the second air storing cavity 16 being communicated with air storing cavity 15 on swivel nut 3, to increase the gas-storing capacity of safety valve.Valve casing 1, with swivel nut 3 and for being threaded, has internal thread on swivel nut 3 inwalls, and the outer wall of valve casing 1 has external screw thread.Between valve casing 1 and swivel nut 3, be provided with O RunddichtringO 11, this O RunddichtringO 11 is quality of rubber materials.In swivel nut 3, be also provided with a limiting plate 4, the inwall of swivel nut 3 is provided with the step of placing this limiting plate 4, the end that valve casing 1 is connected with swivel nut 3 is resisted against on this limiting plate 4, is also provided with the air storing cavity 15 that is communicated with on swivel nut 3 and the through hole of the second air storing cavity 16 on limiting plate 4.
As shown in Figure 1, the end towards swivel nut 3 of spool 2 has the 3rd air storing cavity 17, the three air storing cavity 17 also with the second air storing cavities 16 that are communicated with air storing cavity 15 on swivel nut 3 and communicates, and further increases the gas-storing capacity of safety valve.The end towards fuel feed hole of spool 2 has two deep holes that are communicated with fuel feed hole, and this two deep holes symmetry is located on spool 2, is respectively equipped with a unloading hole on each deep hole.Between spool 2 and valve casing 1, be provided with 3 O RunddichtringOs 13, lay respectively at the position of the unloading hole both sides on valve casing 1, this O RunddichtringO 13 is speciality O type circle, adopts polyurethane material to make, and has good sealing effectiveness.
As shown in Figure 1, blind end at swivel nut 3 is also provided with charge valve 5 and screw plug 8, screw plug 8 is threaded with swivel nut 3 and covers charge valve 5, this charge valve 5 is located on the blind end of swivel nut 3, charge valve 5 one end are positioned at swivel nut 3 inside, the other end is positioned at swivel nut 3 outsides, the end that charge valve 5 is positioned at swivel nut 3 inside has flange, the end that is positioned at swivel nut 3 outsides is provided with pad 7, on charge valve 5, also cover has spring 6, one end of this spring 6 is against on this pad 7, and the other end is against on the outer wall of blind end of swivel nut 3, in charge valve 5, has air-filled pore.Between charge valve 5 and swivel nut 3, be also provided with O RunddichtringO 10, between screw plug 8 and swivel nut 3, be provided with O RunddichtringO 9, to improve sealing performance, prevent nitrogen leakage.The end being connected with the oil cylinder of hydraulic support at valve casing 1 is also provided with O RunddichtringO 13, prevents hydraulic oil leakage.
The operating principle of safety valve: when the cylinder force of hydraulic support surpasses the air pressure in the air storing cavity 15 of safety valve, under the promotion of the hydraulic oil of spool 2 in the fuel feed hole that enters valve casing 1 to the interior movement of air storing cavity 15, when the unloading hole on spool 2 moves past O RunddichtringO 12, entering hydraulic oil in the spool 2 deep holes unloading hole from valve casing 1 discharges, because there is sealing performance reliably spool 2 and valve casing 1 inside, hydraulic oil can not enter air storing cavity 15.Along with constantly sending of hydraulic oil, the pressure in oil cylinder can reduce along with off-load, and when the pressure of oil cylinder is less than the air pressure in air storing cavity 15, spool 2 is resetted by gas pressure, recovers sealing state.
Safety valve has advantages of simple in structure, good sealing effect, longer service life, and reliability is higher.
By reference to the accompanying drawings the present invention is exemplarily described above; obviously specific implementation of the present invention is not subject to the restrictions described above; as long as adopted the improvement of the various unsubstantialities that method of the present invention design and technical scheme carry out; or without improving, design of the present invention and technical scheme are directly applied to other occasion, all within protection scope of the present invention.
Claims (1)
1. the nitrogen safety valve for colliery comprehensive mining hydraulic bracket, comprise valve casing (1) and spool (2), it is characterized in that: described spool (2) is built in the valve opening of described valve casing (1), on the outer wall of spool (2) and valve casing (1), be provided with unloading hole, one end of valve casing (1) is connected with the oil cylinder of described hydraulic support, the other end is connected with the one end of a swivel nut (3), the other end sealing of this swivel nut (3), valve casing has fuel feed hole on (1), in swivel nut (3), there is air storing cavity (15), air storing cavity stores nitrogen in (15), valve opening is communicated with fuel feed hole and air storing cavity (15), under the effect of the spool in valve opening (2) nitrogen in air storing cavity (15), reset, the end that described valve casing (1) is connected with described swivel nut (3) has the second air storing cavity (16) being communicated with air storing cavity (15) on swivel nut (3), described valve casing (1) with described swivel nut (3) for being threaded, in described swivel nut (3), be provided with a limiting plate (4), the inwall of swivel nut (3) is provided with the step of placing this limiting plate (4), it is upper that the end that described valve casing (1) is connected with swivel nut (3) is resisted against this limiting plate (4), is also provided with the air storing cavity (15) that is communicated with on described swivel nut (3) and the through hole of the second air storing cavity (16) on limiting plate (4), the end towards described swivel nut (3) of described spool (2) has the 3rd air storing cavity (17) being communicated with air storing cavity (15) on swivel nut (3),
The end towards described fuel feed hole of described spool (2) has two deep holes that are communicated with fuel feed hole, is respectively equipped with a described unloading hole on each deep hole; Between described spool (2) and described valve casing (1), be provided with O RunddichtringO (12); Between described valve casing (1) and described swivel nut (3), be provided with O RunddichtringO (11).
Priority Applications (1)
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CN201410197673.0A CN103953370B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
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CN201210228756.2A CN102748041B (en) | 2012-07-04 | 2012-07-04 | Nitrogen safety valve for hydraulic support in coal mine fully mechanized mining |
CN201410197673.0A CN103953370B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
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CN201210228756.2A Division CN102748041B (en) | 2012-07-04 | 2012-07-04 | Nitrogen safety valve for hydraulic support in coal mine fully mechanized mining |
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CN103953370A true CN103953370A (en) | 2014-07-30 |
CN103953370B CN103953370B (en) | 2016-01-27 |
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CN201410197695.7A Active CN103953372B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
CN201410197673.0A Active CN103953370B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
CN201410197693.8A Active CN103953371B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
CN201210228756.2A Active CN102748041B (en) | 2012-07-04 | 2012-07-04 | Nitrogen safety valve for hydraulic support in coal mine fully mechanized mining |
CN201410197657.1A Active CN103953369B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
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CN201410197695.7A Active CN103953372B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
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CN201410197693.8A Active CN103953371B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
CN201210228756.2A Active CN102748041B (en) | 2012-07-04 | 2012-07-04 | Nitrogen safety valve for hydraulic support in coal mine fully mechanized mining |
CN201410197657.1A Active CN103953369B (en) | 2012-07-04 | 2012-07-04 | A kind of nitrogen safety valve for colliery comprehensive mining hydraulic bracket |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107725083A (en) * | 2017-11-24 | 2018-02-23 | 鸿大智能机械有限公司 | The nitrogen safety valve that coal supply ore deposit comprehensive mining hydraulic bracket uses |
CN108894805A (en) * | 2018-06-16 | 2018-11-27 | 浙江中煤液压机械有限公司 | A kind of emulsion pump inflation safety valve |
Families Citing this family (6)
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CN104976187B (en) * | 2015-07-13 | 2018-03-27 | 王润宏 | A kind of safety valve for hydraulic pressure of the colliery system |
CN105298527A (en) * | 2015-11-26 | 2016-02-03 | 巨隆集团芜湖兴隆液压有限公司 | Opening and closing mechanism of overflowing safety valve |
CN105386782A (en) * | 2015-11-26 | 2016-03-09 | 巨隆集团芜湖兴隆液压有限公司 | Overflow safety valve |
CN106382125B (en) * | 2016-12-01 | 2018-05-08 | 安徽理工大学 | Colliery pressure three-purpose valve based on micro forming spool and special-shaped valve chamber |
CN110905576B (en) | 2019-12-12 | 2020-12-08 | 山东科技大学 | Hydraulic support magneto-rheological pilot operated safety valve based on magnetic control material and application thereof |
CN112576565B (en) * | 2020-11-27 | 2023-08-22 | 北京天玛智控科技股份有限公司 | Inflatable safety valve |
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CN107725083A (en) * | 2017-11-24 | 2018-02-23 | 鸿大智能机械有限公司 | The nitrogen safety valve that coal supply ore deposit comprehensive mining hydraulic bracket uses |
CN108894805A (en) * | 2018-06-16 | 2018-11-27 | 浙江中煤液压机械有限公司 | A kind of emulsion pump inflation safety valve |
Also Published As
Publication number | Publication date |
---|---|
CN102748041A (en) | 2012-10-24 |
CN103953372B (en) | 2016-02-10 |
CN103953369B (en) | 2016-01-27 |
CN103953371A (en) | 2014-07-30 |
CN103953369A (en) | 2014-07-30 |
CN103953371B (en) | 2016-02-10 |
CN103953370B (en) | 2016-01-27 |
CN103953372A (en) | 2014-07-30 |
CN102748041B (en) | 2014-10-01 |
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