CN103212154A - One-way positive valve - Google Patents

One-way positive valve Download PDF

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Publication number
CN103212154A
CN103212154A CN 201210019406 CN201210019406A CN103212154A CN 103212154 A CN103212154 A CN 103212154A CN 201210019406 CN201210019406 CN 201210019406 CN 201210019406 A CN201210019406 A CN 201210019406A CN 103212154 A CN103212154 A CN 103212154A
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CN
China
Prior art keywords
valve
flexible member
plunger portion
cavity
unidirectional positive
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Pending
Application number
CN 201210019406
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Chinese (zh)
Inventor
王晓东
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AMSINO HEALTHCARE (SHANGHAI) Co Ltd
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AMSINO HEALTHCARE (SHANGHAI) Co Ltd
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Publication date
Application filed by AMSINO HEALTHCARE (SHANGHAI) Co Ltd filed Critical AMSINO HEALTHCARE (SHANGHAI) Co Ltd
Priority to CN 201210019406 priority Critical patent/CN103212154A/en
Publication of CN103212154A publication Critical patent/CN103212154A/en
Pending legal-status Critical Current

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Abstract

The invention discloses a one-way positive valve, which comprises a valve casing, a valve base and an elastic element. The valve casing comprises a valve casing body and a liquid inlet, wherein the liquid inlet is arranged on the valve casing body; the valve base comprises a substrate, a liquid outlet, a gas passage and a liquid passage, wherein the liquid outlet, the gas passage and the liquid passage are arranged on the substrate; the valve casing body and the substrate of the valve base are connected with each other in a sealing way, and define a valve cavity together; and the valve cavity is communicated with the liquid outlet through the liquid passage on the substrate of the valve base. The elastic element comprises an elastic element body and a plunger; both the elastic element body and the plunger are provided with cavities; one end of the elastic element body is connected with the upper surface of the substrate of the valve base in a sealing way, and the other end of the elastic element body is connected with the plunger; and the cavity of the elastic element body is communicated with the atmosphere through the gas passage arranged on the substrate of the valve base. The one-way positive valve is simple in structure, acting force of the elastic element on the valve is small, and enough positive pressure can be generated.

Description

Unidirectional positive valve
Technical field
The present invention relates to valve, relate in particular to the unidirectional positive valve that cooperates transfusion catheter and syringe use clinically, can prevent medicinal liquid backflow and blood back.
Background technology
At present, need to infuse in the venous transfusion therapeutic process or when injecting, multiselect is with venous detaining needle or inlying catheter prolonged and repeatedly.Usually connect the threeway conduit on these venous detaining needles or the inlying catheter, be furnished with standard Luer (Luer) joint or calparine cap on the threeway conduit usually, to satisfy the clinical requirement of multiple transfusion.But there is certain defective in above-mentioned medical apparatus and instruments in clinical use: the use of female Luer on the tee T, and need carry out partly sterilised at every turn, and will use entry needle to puncture, so just increase work load and operational risk to medical and nursing work; The use of calparine cap then needs medical personnel after the filling medicinal liquid, and injection heparin or normal saline carry out tube sealing in calparine cap, prevents that blood coagulation from forming thrombosis, and this brings burden to clinical manipulation equally.In addition, the application of calparine cap also might cause little air to enter blood circulation, has risk.Simultaneously, above-mentioned two class apparatuses all can't solve after transfusion finishes, because the negative pressure that produces when drawing back entry needle or not having needle adapter causes blood of human body to pass back into the indwelling flexible pipe, blood coagulation is blocked needle tubing, stop transfusion next time and the serious potential safety hazard that produces.
For preventing above-mentioned malpractice, people design unidirectional positive valve and are applied in the clinical transfusion process.Known unidirectional positive valve is made of the parts more than four mostly, and structure is comparatively complicated, has brought inconvenience for manufacturing and assembling.In addition, existing unidirectional positive valve mostly adopts spring as flexible member, because spring is bigger to the active force of valve body, causes the damage of valve body sometimes.In addition, the spring of metal material more easily produces elastic fatigue, can't thoroughly sterilize, and has brought potential safety hazard to infusion process.
Summary of the invention
Technical problem to be solved by this invention is to overcome the above-mentioned shortcoming of prior art, a kind of unidirectional positive valve is provided, it is after finishing transfusion, produce the unidirectional normal pressure that prevents medicinal liquid backflow even blood back by valve itself, in addition, this unidirectional positive valve simple in structure, flexible member is little to the active force of valve itself, and can produce enough malleation amounts.
The technical solution used in the present invention is: a kind of unidirectional positive valve comprises valve casing, valve seat and flexible member; Valve casing comprises valve casing body and the liquid inlet that is arranged on the valve casing body, and valve seat comprises pedestal and the liquid outlet, gas passage and the fluid passage that are arranged on this pedestal; The pedestal of valve casing body and this valve seat is tightly connected, and surrounds a valve pocket jointly, and this valve pocket is communicated with liquid outlet by the fluid passage of being located on the valve seat pedestal; Flexible member comprises a flexible member body and a plunger portion; Flexible member body and plunger portion are equipped with cavity; The upper surface of one end of flexible member body and the pedestal of valve seat is tightly connected, and the other end of this flexible member body links to each other with plunger portion; The cavity of this flexible member body is communicated with atmosphere by the gas passage of being located on the valve seat pedestal; When unidirectional positive valve was in closed condition, plunger portion was closed and the seal fluid inlet; When unidirectional positive valve was in opening, the liquid that flows into from the liquid inlet was successively by influent outlet behind valve pocket and the fluid passage.
The invention has the beneficial effects as follows:
When 1, unidirectional positive valve of the present invention was in open mode, flexible member was compressed, smaller volume, and it is big that the volume of the flow path of the liquid in the valve pocket becomes; And finish when using, after external force is eliminated, the flexible member body promotes the plunger portion resilience, unidirectional positive valve cuts out, flexible member restores to the original state, and becomes big when the more unidirectional positive valve of volume is in open mode, the smaller volume of the flow path of the liquid in the valve pocket, thereby produce the normal pressure of valve pocket inner liquid medicine, prevent that medicinal liquid from refluxing even blood back to the liquid outlet promotion.Therefore, unidirectional positive valve of the present invention is finished when screwing out syringe, transfusion device etc. in transfusion, can avoid causing medicinal liquid to reflux even blood is back to the phenomenon of veins indwelling catheter because of producing negative pressure.The present invention adopts the needleless operation, has ensured medical personnel's safety, has improved medical and nursing work efficient, has alleviated patient's misery;
2. flexible member of the present invention is compared with spring, and is little to the active force of valve body.And, because the intrinsic cavity of flexible member is communicated with atmosphere, in the time of can avoiding the flexible member body to be compressed at the excessive air pressure of this cavity inner accumulated, thereby can make flexible member obtain bigger compress variation, allow unidirectional positive valve produce enough malleation amounts;
3. the present invention only is made up of three parts, and is simple in structure, is convenient to assembling, thereby improved production efficiency;
4. elastomer element of the present invention adopts the non-metallic elastic material manufacturing, is convenient to use together in conjunction with the antibacterial material, also makes the present invention be suitable for using the occasion of MRI.
Description of drawings
Fig. 1 is the sketch map of unidirectional positive valve one embodiment of the present invention when being in closed condition.
Fig. 2 is the sketch map of unidirectional positive valve one embodiment of the present invention when being in opening.
Fig. 3 is the sketch map of another embodiment of the unidirectional positive valve of the present invention when being in closed condition.
The specific embodiment
Below in conjunction with accompanying drawing the present invention is made and to further specify.
With reference to figure 1 and Fig. 2.Unidirectional according to an embodiment of the invention positive valve is made up of valve casing 1, valve seat 2, flexible member 3.Wherein, valve casing 1 is made up of valve casing body 11 and liquid inlet 12, and liquid inlet 12 is arranged on an end of valve casing body 11.Only show a liquid inlet in the drawings, also can in the side of valve casing body a plurality of liquid inlets be set according to the requirement of transfusion.
Valve seat 2 is made up of pedestal 21 and the fluid passage 23, gas passage 24 and the liquid outlet 25 that are arranged on this pedestal 21.Valve casing body 11 is tightly connected with the pedestal 21 of valve seat, and surrounds a valve pocket 13 jointly, and valve pocket 13 is communicated with liquid outlet 25 by the fluid passage of being located on the pedestal 21 23.Preferably, liquid inlet 12 and liquid outlet 25 are equipped with the standard Luer joint.
Flexible member 3 comprises a flexible member body 31 and a plunger portion 32.Be provided with cavity 311 in the flexible member body 31, when strain takes place in flexible member body 31, the volume generation significant change of cavity 311.Be provided with cavity 321 in the plunger portion 32.In embodiment illustrated in figures 1 and 2, the cavity 321 of plunger portion is opened on the side of this plunger portion, is not communicated with mutually with the intrinsic cavity 311 of flexible member, and the shape of cross section of this cavity 321 is a rhombus.The cavity 321 of plunger portion can be an end opening in the side of plunger portion and other end sealing also can be the lateral through hole that laterally runs through this plunger portion 32.The upper surface of one end of flexible member body 31 and the pedestal 21 of valve seat is tightly connected, and separates with the liquid flow path that cavity 311 and flexible member is outer.In one embodiment, the upper surface 210 of the pedestal 21 of valve seat is provided with a boss 22, and boss 22 is provided with a central through hole 221 that is connected with gas passage 24.One end of flexible member body 31 is set on this boss 22, the cavity wall interference fit of the outer wall of boss 22 and this flexible member body.The cavity 311 of flexible member body is communicated with atmosphere by central through hole 221 and the gas passage of being located on the valve seat pedestal 24.Among the figure, flexible member body 31 further comprises connecting portion 313 and corrugated part 314; One end of connecting portion 313 is set on the boss 22, and corrugated part 314 links to each other with the other end of connecting portion 313, and the cross sectional shape of the sidewall of corrugated part 314 is a corrugated.In another embodiment, also boss 22 can be set, make connecting portion 313 directly and the upper surface 210 of the pedestal 21 of valve seat be tightly connected, at this moment, the cavity 311 of flexible member body is communicated with atmosphere by the gas passage of being located on the valve seat pedestal 24.The other end of flexible member body 31 links to each other with plunger portion 32, and flexible member body 31 can provide a resilience force to the direction resilience of described liquid inlet to plunger portion.Preferably, the perisporium of the end that links to each other with flexible member body 31 of plunger portion 32 is provided with annular groove 322.
The material of flexible member 3 preferably adopts non-metallic elastic material, for example silica gel, rubber etc.
The valve casing body 11 of the unidirectional positive valve of the present invention is arranged on the pedestal 21 of valve seat 2.Be interference fit between the inwall of plunger portion 32 and liquid inlet 12, like this, when unidirectional positive valve was in closed condition, plunger portion 32 can be closed and seal fluid inlet 12.In valve pocket 13, the space between the outer wall of the inwall of valve casing body 11 and flexible member 3 has constituted liquid flow path, and 12 liquid that flow into valve pocket 13 can export 25 by this liquid flow path influent from the liquid inlet, thereby can infuse.
As depicted in figs. 1 and 2, the operation principle of unidirectional positive valve is according to an embodiment of the invention:
After the preexhaust process, be full of normal saline or medicinal liquid in the unidirectional positive valve, the use of can infusing.When unidirectional positive valve was in opening, the upper surface of plunger portion 32 was by external female Luer 4 pushings, and the cavity 321 in the plunger portion 32 produces distortion under pressure, and volume diminishes.Plunger portion 32 transfers the pressure on the flexible member body 31 simultaneously, causes 31 compressions of flexible member body, and the liquid in the cavity 311 of flexible member body is discharged by the gas passage 24 of valve seat.The smaller volume of flexible member body 31, thereby plunger portion 32 is dropped under the liquid inlet 12, and elastic deformation takes place in plunger portion 32, its upper surface caves in, and valve pocket 13 is opened, and medicinal liquid is 12 inputs from the liquid inlet, the valve pocket 13 of flowing through, enter the fluid passage 23 of valve seat, in other conduit of inlying catheter that fluid passage 23 flows into the liquid outlet 25 of valve seat 2 links to each other, carry out the process of clinical transfusion then.The flow direction of liquid is shown in arrow among the figure.
When external female Luer 4 is closed unidirectional positive valve by back-out, flexible member 3 loses external force, reinstatement, and air enters in the cavity 311 of flexible member body by the gas passage 24 of valve seat, it is big that the volume of flexible member body 31 becomes, and promotes the position that plunger portion 32 moves to closed condition.Because it is big that the volume of flexible member 3 becomes, the volume of the liquid flow path in the valve pocket 13 diminishes, because the volume-variation of liquid flow path, generation promotes normal pressure from liquid residual in the valve to liquid outlet, make the residual medicinal liquid in the valve pocket 13, continuation enters into by valve pocket 13 in the fluid passage 23 of valve seat, and the liquid outlet 25 from valve seat flows out then.That is, make the residual liquor in the valve,, continue to flow along former flow direction.Thereby avoided medicinal liquid because the caused medicinal liquid of negative pressure that produces when screwing out external female Luer refluxes even blood refluxes.
Fig. 3 shows an alternative embodiment of the invention.In this embodiment, the cavitys 321 in the plunger portion 32 are not communicated with mutually with the outer surface of plunger portion, and the cavity 311 interior with flexible member body 31 is interconnected.Its operation principle is identical with the above embodiments, is described below:
After the preexhaust process, be full of normal saline or medicinal liquid in the unidirectional positive valve, the use of can infusing.When unidirectional positive valve was in opening, the upper surface of plunger portion 32 was pushed by external female Luer, and the cavity 321 in the plunger portion 32 produces distortion under pressure, and volume diminishes.Plunger portion 32 transfers the pressure on the flexible member body 31 simultaneously, cause 31 compressions of flexible member body, gas in the cavity 321 of plunger portion and the cavity of flexible member body 311 is discharged by the gas passage 24 of valve seat, the smaller volume of flexible member body 31, thereby plunger portion 32 is dropped under the liquid inlet 12, and elastic deformation takes place in plunger portion 32, its upper surface caves in, valve pocket 13 is opened, medicinal liquid is 12 inputs from the liquid inlet, and the valve pocket 13 of flowing through enters the fluid passage 23 of valve seat, in other conduit of inlying catheter that fluid passage 23 flows into the liquid outlet 25 of valve seat 2 links to each other, carry out the process of clinical transfusion then.
When external female Luer is closed unidirectional positive valve by back-out, flexible member 3 loses external force, reinstatement, the gas passage 24 of air by valve seat enters in the cavity 321 of the cavity 311 of flexible member body and plunger portion, it is big that the volume of flexible member body 31 becomes, and promotes the position that plunger portion 32 moves to closed condition.Because it is big that the volume of flexible member 3 becomes, the volume of the liquid flow path in the valve pocket 13 diminishes, because the volume-variation of liquid flow path, generation promotes normal pressure from liquid residual in the valve to medicine liquid outlet, make the residual medicinal liquid in the valve pocket 13, continuation enters into by valve pocket 13 in the fluid passage 23 of valve seat, and the liquid outlet 25 from valve seat flows out then.
The present invention cooperates transfusion catheter or syringe to use clinically.The liquid inlet can connect the female Luer of syringe, transfusion device, tee T etc., and liquid outlet can connect the conduit that inserts human vas.Use the clinical purpose of this unidirectional positive valve to be: after transfusion finishes, when extracting the female Luer of syringe, transfusion device, tee T etc. out, unidirectional positive valve can produce a kind of interior residual liquid of valve that makes and continue mobile normal pressure to former flow direction, prevent to cause medicinal liquid backflow even blood back in valve or in the conduit because of the negative pressure that the female Luer of extracting syringe, transfusion device out produces, this unidirectional positive valve can also be carried multiple liquid simultaneously.In addition, producing under the condition of enough malleation amounts, flexible member by gas discharge and enter and change shape, the suffered active force of flexible member itself is less relatively.
The description of the present embodiment combines certain embodiments, but it should be understood by one skilled in the art that the present invention is not limited to embodiment described here, and can carry out various modifications and variations and do not deviate from the spirit and scope of the present invention.

Claims (10)

1. a unidirectional positive valve is characterized in that, comprises valve casing, valve seat and flexible member;
Described valve casing comprises valve casing body and the liquid inlet that is arranged on the valve casing body, and described valve seat comprises pedestal and the liquid outlet, gas passage and the fluid passage that are arranged on this pedestal; The pedestal of described valve casing body and this valve seat is tightly connected, and surrounds a valve pocket jointly, and this valve pocket is communicated with described liquid outlet by the described fluid passage of being located on the valve seat pedestal;
Described flexible member comprises a flexible member body and a plunger portion; Described flexible member body and described plunger portion are equipped with cavity; The upper surface of one end of described flexible member body and the pedestal of valve seat is tightly connected, and the other end of this flexible member body links to each other with plunger portion; The cavity of this flexible member body is communicated with atmosphere by the described gas passage of being located on the valve seat pedestal;
When described unidirectional positive valve was in closed condition, described plunger portion was closed and the seal fluid inlet; When described unidirectional positive valve was in opening, the liquid that flows into from the liquid inlet was successively by influent outlet behind described valve pocket and the described fluid passage.
2. unidirectional positive valve as claimed in claim 1 is characterized in that, the material of described flexible member is a non-metallic elastic material.
3. unidirectional positive valve as claimed in claim 2 is characterized in that, described non-metallic elastic material is silica gel or rubber.
4. unidirectional positive valve as claimed in claim 1 is characterized in that the upper surface of the pedestal of described valve seat is provided with a boss, and described boss is provided with a central through hole that is connected with described gas passage; One end of described flexible member body is set on this boss, the cavity wall interference fit of the outer wall of this boss and this flexible member body.
5. unidirectional positive valve as claimed in claim 4 is characterized in that, described flexible member body further comprises connecting portion and corrugated part; One end of described connecting portion is set on this boss, and described corrugated part links to each other with the other end of connecting portion, and the cross sectional shape of the sidewall of corrugated part is a corrugated.
6. unidirectional positive valve as claimed in claim 1 is characterized in that, the cavity of the plunger portion of described flexible member is opened on the side of this plunger portion.
7. unidirectional positive valve as claimed in claim 6 is characterized in that, the cavity of the plunger portion of described flexible member is the lateral through hole that runs through this plunger portion.
8. unidirectional positive valve as claimed in claim 1 is characterized in that, the cavity of the cavity of the plunger portion of described flexible member and this flexible member body is interconnected, and is not communicated with mutually with the outer surface of this plunger portion.
9. unidirectional positive valve as claimed in claim 1 is characterized in that, described plunger portion is provided with annular groove with the perisporium of the end that described flexible member body links to each other.
10. unidirectional positive valve as claimed in claim 1 is characterized in that described liquid inlet and liquid outlet are equipped with the standard Luer joint.
CN 201210019406 2012-01-21 2012-01-21 One-way positive valve Pending CN103212154A (en)

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Application Number Priority Date Filing Date Title
CN 201210019406 CN103212154A (en) 2012-01-21 2012-01-21 One-way positive valve

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Application Number Priority Date Filing Date Title
CN 201210019406 CN103212154A (en) 2012-01-21 2012-01-21 One-way positive valve

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CN103212154A true CN103212154A (en) 2013-07-24

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103845791A (en) * 2014-03-13 2014-06-11 李宜 Indwelling catheter trace slow-release transfusion device
CN104720827A (en) * 2015-03-27 2015-06-24 河北鑫乐医疗器械科技股份有限公司 Blood taking tool anti-counter-flow structure and blood taking needle with same
CN105771029A (en) * 2016-04-29 2016-07-20 光玲 Anti-reflux positive pressure device
CN106267451A (en) * 2016-08-23 2017-01-04 徐俊鸽 A kind of venous detaining needle
WO2017016093A1 (en) * 2015-07-29 2017-02-02 佳承精工股份有限公司 Positive pressure needle-free injection cap
CN107802920A (en) * 2017-12-17 2018-03-16 湖南平安医械科技有限公司 A kind of security closed positive pressure needle-free joint
CN108815698A (en) * 2018-07-06 2018-11-16 苏州鑫康道医疗科技有限公司 Continuous positive pressure connector
CN108837224A (en) * 2018-07-16 2018-11-20 杭州光启医疗科技发展有限公司 The medical fluid delivery instrument of anti-backflow
CN111544709A (en) * 2020-05-14 2020-08-18 郑孝祥 Infusion apparatus for pediatrics
CN111569183A (en) * 2020-05-14 2020-08-25 郑孝祥 Infusion apparatus with air-flow-preventing and blood-return functions for department of pediatrics
CN117563122A (en) * 2023-12-21 2024-02-20 燕山大学 Pressure control valve for blood system and pressure regulating method thereof

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103845791A (en) * 2014-03-13 2014-06-11 李宜 Indwelling catheter trace slow-release transfusion device
CN103845791B (en) * 2014-03-13 2017-01-11 广东先来医疗器械有限公司 Indwelling catheter trace slow-release transfusion device
CN104720827A (en) * 2015-03-27 2015-06-24 河北鑫乐医疗器械科技股份有限公司 Blood taking tool anti-counter-flow structure and blood taking needle with same
WO2017016093A1 (en) * 2015-07-29 2017-02-02 佳承精工股份有限公司 Positive pressure needle-free injection cap
CN105771029A (en) * 2016-04-29 2016-07-20 光玲 Anti-reflux positive pressure device
CN106267451A (en) * 2016-08-23 2017-01-04 徐俊鸽 A kind of venous detaining needle
CN107802920A (en) * 2017-12-17 2018-03-16 湖南平安医械科技有限公司 A kind of security closed positive pressure needle-free joint
CN108815698A (en) * 2018-07-06 2018-11-16 苏州鑫康道医疗科技有限公司 Continuous positive pressure connector
CN108837224A (en) * 2018-07-16 2018-11-20 杭州光启医疗科技发展有限公司 The medical fluid delivery instrument of anti-backflow
CN108837224B (en) * 2018-07-16 2021-02-02 青岛市精神卫生中心(青岛市第七人民医院、青岛市心理咨询中心) Liquid medicine delivery device capable of preventing backflow
CN111544709A (en) * 2020-05-14 2020-08-18 郑孝祥 Infusion apparatus for pediatrics
CN111569183A (en) * 2020-05-14 2020-08-25 郑孝祥 Infusion apparatus with air-flow-preventing and blood-return functions for department of pediatrics
CN117563122A (en) * 2023-12-21 2024-02-20 燕山大学 Pressure control valve for blood system and pressure regulating method thereof

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Application publication date: 20130724