CN2920294Y - A reverse flow prevention valve including an expansion device and the expansion device - Google Patents

Abstract

The utility model provides a countercurrent preventing valve containing an expansion device, and the countercurrent preventing valve includes a cylinder part, as well as a crow mouth part at one side of the cylinder part, the crow mouth part is the symmetric anti-inverse wedge valve structure formed by flatting the two sides of the front end of the cylinder part gradually, the front end of the anti-inverse wedge valve structure is a rectangular cross-section or a similar rectangular cross-section, a valve opening having the line-shape middle slot is provided along the direction of the length, the utility model is characterized in that the countercurrent preventing valve also contains the expansion device, the expansion device includes a pair of column shape members positioned in the inner side of the countercurrent preventing valve and located at the two ends of the valve opening, and the expansion device drives the valve opening to expand outside. The utility model also provides an expansion device which is the same as the above said. The utility model can effectively improve the existing closing performance of the countercurrent preventing valve in the indwelling needle and achieve simple, precise, quick and reliable closure.

Description

A reverse flow prevention valve including an expansion device and the expansion device

technical field

The utility model relates to a medical device, in particular to a backflow prevention valve including an expansion device and the expansion device.

Background technique

The indwelling needle includes an inner needle and an outer needle. The inner needle is arranged on the inside of the outer needle. When the indwelling needle is inserted into the blood vessel, the outer needle is placed in the blood vessel and the inner needle is pulled out, so that multiple infusions can be performed thereafter.

The application of indwelling needles reduces the repeated puncture of blood vessels by medical staff, and at the same time reduces the pain of patients. Greatly shorten the time of infusion operation.

In order to prevent the hidden danger of blood backflow through the indwelling needle caused by the pressure at the infusion infusion end of the indwelling needle being lower than the blood pressure at the outflow end when the infusion is completed, the existing indwelling needles are generally equipped with a backflow prevention valve. The wedge-shaped anti-reverse valve structure on the upper body prevents blood from flowing backward. Since the shape of the wedge-shaped anti-reverse valve structure is similar to that of a crow's bill, it is referred to as the crow's mouth hereinafter. The structure of the crow's mouth is usually made of soft materials such as silica gel. The crow's mouth can effectively ensure the smooth input of medicinal liquid into veins or arteries and prevent blood backflow. Such as the anti-reverse flow venous indwelling needle disclosed in Chinese Patent No. 200420078043.3.

But because there is no other auxiliary measures at the front end valve port of the black duckbill in the anti-backflow venous indwelling needle, when the indwelling needle is used, when the inner needle passes through the backflow prevention valve, the two adjacent closing lengths of the valve port There will be a certain gap after the inner needle is pulled out, and a small amount of blood will flow back through the gap, especially if the inner needle is positioned at the valve port for a long time, the closing force of the valve port will decrease, so that the closed part cannot be closed quickly after the inner needle is pulled out. Closing will cause blood to flow back along the valve port; in addition, when the indwelling needle is left in the blood vessel for a long time or the drip time is long, the valve port may not be completely closed due to weak closing force and repeated use. If the drip tube falls off during the drip Or blood backflow will occur at the end of the infusion, causing the risk of massive bleeding.

In addition, the wedge-shaped anti-reverse valve constituting the duckbill has parallel inner and outer surfaces. Such a structure will cause the valve to close automatically under the action of the elastic force of the valve itself when the pressure difference between the two ends of the valve port is small. Therefore, when the pressure When the difference is positive, that is, when the pressure at the input end of the backflow prevention valve is slightly greater than the pressure at the output end, that is, when the blood pressure in the blood vessel is slightly lower than the infusion pressure, the valve port is closed and the liquid input cannot be performed. Therefore, the backflow prevention valve with this structure Reliable infusion under small pressure differentials cannot be guaranteed.

To sum up, the existing backflow prevention valves have defects such as poor anti-backflow performance, low response sensitivity, poor infusion reliability at small pressure differences, and large safety hazards, which largely limit their applications.

Utility model content

Aiming at the defects and deficiencies of the backflow prevention valve in the existing indwelling needles, the purpose of the utility model is to provide a backflow prevention valve and the expansion device including an expansion device which can eliminate the above defects and deficiencies.

The technical scheme of the utility model is as follows:

A backflow prevention valve including an expansion device, the backflow prevention valve includes a cylindrical part and a crow's mouth located on one side of the cylindrical part, and the crow's mouth is gradually flattened from both sides of the front end of the cylindrical part. A symmetrical wedge-shaped anti-reversal valve structure is formed. The front end of the wedge-shaped anti-reverse valve structure is a rectangular section or an approximately rectangular section. An expansion device is also included, and the expansion device includes a pair of column parts arranged inside the backflow prevention valve and located at both ends of the valve port, and can drive the valve port to expand outwards.

The two column parts are arranged in parallel along the axial direction of the backflow prevention valve and expand outward only at their respective front ends.

The section of the columnar part is triangular.

The inner side of the front end gradually converges toward the outer side.

The wedge-shaped anti-reversal valve has inner and outer surfaces with different inclination angles, and the inclination angle of the inner surface is slightly smaller than the inclination angle of the outer surface.

The outer surface of the wedge-shaped anti-reverse valve is composed of two planes with different inclination angles, wherein the inclination angle of the plane close to the valve port is smaller than the inclination angle of the plane far away from the valve port.

An expansion device as described above, characterized in that: the expansion device includes a pair of cylindrical parts that can be arranged inside the backflow prevention valve and located at both ends of the valve port and can drive the valve port to expand outwards; Mounting part for fixing the columnar part.

The two column parts are arranged in parallel along the axial direction of the backflow prevention valve and expand outward only at their respective front ends.

The cross-section of the columnar part is triangular, and the front end thereof converges outward into a wedge shape.

The installation part is a cylindrical structure and fits inside the cylindrical part of the backflow prevention valve.

The technical effect of the utility model is:

The utility model arranges an expansion device in the backflow prevention valve, and the expansion device includes a pair of columnar parts arranged inside the backflow prevention valve and located at both ends of the valve port, which can drive the valve port to expand outwards.

Because the valve port of the backflow prevention valve expands outwards under the action of the expansion device, and the backflow prevention valve is generally made of soft materials such as silica gel, which has good elasticity, and the closing part of the valve port is subjected to lateral stretching. It acts and naturally fits to the joint part, thereby increasing the closing force of the closing part and improving the effect of preventing backflow. Therefore, the utility model can significantly improve the anti-reverse effect of the existing anti-backflow valve, so that the anti-backflow valve can prevent blood backflow simply, precisely and reliably. The anti-backflow valve has the characteristics of fast closing, making the response of the anti-backflow valve more sensitive and reliable, which can effectively improve the safety of the anti-backflow valve, and solve the problem of the existing backflow prevention valve due to weak closing force. The problem of reverse flow of blood.

The utility model also sets the wedge-shaped anti-reversal valve of the crow's mouth as inner and outer surfaces with different inclination angles, and the inclination angle of the inner surface is slightly smaller than the inclination angle of the outer surface. In such an anti-reverse structure, the pressure at the liquid input end is slightly greater than that at the output end. When the positive pressure difference between the two ends of the reverse flow prevention valve is very small, the pressure acting on the inside of the wedge-shaped valve will more effectively promote the opening of the valve port, thus reliably ensuring that the valve port can still work normally under the condition of small positive pressure difference. Turn on for infusion operation.

In addition, in the anti-reflux valve of the present invention, the wedge-shaped valve also has the following structure: the included angle between the front part of its outer surface and the axial projection plane is smaller than the included angle between the rear part of its outer surface and the axial projection surface.

Such a structure optimizes the wedge-shaped valve's stress condition. While not reducing the structural strength of the anti-reflux valve, the pressure of the wedge-shaped valve from the blood vessel is the force component in the direction perpendicular to the closed contact part of the valve port. Larger, that is to say, the force to close the valve port is greater, so the anti-reverse effect and performance are also more significant.

The utility model also provides an expansion device as described above, the expansion device includes a pair of columnar parts that can be arranged inside the backflow prevention valve and located at both ends of the valve port and can drive the valve port to expand outwards; Mounting part for fixing the columnar part.

Since the two outwardly expanding cylindrical parts of the expansion device are respectively arranged on both sides of the valve port of the backflow prevention valve, the two ends of the valve port of the crow's mouth are expanded outward, so that the closing parts on both sides of the valve port have a certain tension , and under the action of the tension, the closing part tends to shrink in the closing direction, so as to achieve the purpose of enhancing the closing force of the valve port.

The columnar members are arranged parallel to the axial direction of the backflow preventing valve and expand outward only at their respective front ends. Since most of the columnar parts are arranged in parallel and only expand outward at the front end, such a structure can not only achieve the purpose of expanding the valve port, but also facilitate the installation and positioning of the expansion device in the backflow prevention valve.

Therefore, the expansion device has simple structure, reliable action, and is convenient for processing and installation.

Description of drawings

Fig. 1 is a structural schematic diagram of a backflow prevention valve including an expansion device of the present invention.

FIG. 2 is a schematic top view of the structure of FIG. 1 .

FIG. 3 is a schematic structural diagram of the left view of FIG. 1 .

1-backflow prevention valve, 2-expansion device, 11-black duck mouth, 12-cylindrical part, 13-installation part, 21-columnar body, 22-expansion body, 23-small cylindrical part, 112-front slope Surface, 113-rear slope surface, 114-inner side, 115-section, 116-opening line, 117-valve port, 118-long side, 119-long side.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described.

As shown in Fig. 1, it is a structural schematic diagram of the reverse flow preventing valve of the present invention. The expansion device 2 is arranged inside the anti-backflow valve 1. The anti-backflow valve 1 includes a cylindrical part 12, a duckbill part 11 located at the front of the cylindrical part 12, and a mounting part 13 located at the rear of the cylindrical part 12, wherein the mounting part 13 is matched with the outer needle seat of indwelling needle. The expansion device 2 includes a small cylindrical portion 23, a columnar body 21 and an expansion body 22 located at the front of the cylindrical body 21, wherein the small cylindrical portion 23 is adapted and connected to the inner side of the cylindrical portion 12, and the cylindrical body 21 is symmetrically arranged on the small cylindrical body. The cylindrical portion 23 has one end and two sides.

The black duckbill 11 is a symmetrically arranged wedge-shaped anti-reversal valve structure formed by gradually flattening the two sides of the cylindrical part 12. The front end of the wedge-shaped anti-reversal valve structure is a rectangular or approximately rectangular section 115. Slope 112 and rear slope 113, the rear slope 113 has a greater inclination angle than the front slope 112, as shown in Figure 2, the inclination of the inner surface 114 of the wedge-shaped valve is slightly smaller than the inclination of the front slope, both sides The intersecting front ends of the inner surfaces 114 form a slotted line 116. Of course, the two inner sides 114 do not need to intersect but form a rectangular section. A slit forms the valve port 117 .

For the inner surface 114 , as the inclination angle of the inner surface 114 changes, the width of the valve port 117 changes accordingly. In extreme cases, the valve port 117 coincides with the center line of the section 115 .

In this embodiment, the outer surface of the wedge-shaped valve is divided into a front slope surface 112 and a rear slope surface 113, and the rear slope surface 113 has a larger inclination angle than the front slope surface 112. On the one hand, the rear slope surface 113 has a larger inclination angle. , then this part has a larger thickness, which can well ensure the structural strength of the black duckbill 11; The component force in the direction will be increased, thereby effectively improving the force condition of the valve port 117 and improving the closing effect of the valve port 117 .

For the expansion device 2, the columnar body 21 is a triangular prism structure arranged in parallel, and of course it can also be other columnar structures, such as round rods or quadrangular prisms. The expansion body 22 is located at the front end of the columnar body 21. The tendency to converge toward the outer surface of the front end is mainly to improve and strengthen the elasticity of the expansion body 22 and reduce its weight to the greatest extent. The outer side of the columnar body 21 and the expansion body 22 is in contact with the inner side of the backflow prevention valve 1, and the black duckbill 11 is stretched to both ends under the action of the expansion body 22, thereby driving the front end of the duckbill 11 to expand to both ends, as shown in Figure 3 As shown, this expansion will generate tension in the material near the valve port 117 to extrude to the valve port 117, and this tension will increase the closing force of the valve port 117, so that the two phases of the section 115 adhere to the long sides 118, 119. Close quickly and tightly, so that the valve port 117 can be closed simply, precisely, quickly and reliably, so that the utility model has a more effective anti-reversal effect.

Of course, it is also possible not to expand at the front end of the columnar body 21, and the columnar bodies 21 on both sides are not arranged in parallel but gradually expanded to the outside, and the distance between the front ends of the two columnar bodies 21 is greater than the inner diameter of the cylindrical portion 12. A preferred solution is that the expansion body 22 is located at the front ends of the two cylindrical bodies 21 and penetrates into the crow's mouth 11 inside the cylindrical portion 12, so that the closing force of the valve port 117 is stronger.

The above descriptions are only preferred implementations of the present utility model. It should be pointed out that for those skilled in the art, many variations and improvements can be made according to the concepts and solutions of the present utility model, but these variations and improvements will all fall within the protection scope of the utility model.

Claims (10)

1. check valve that includes extension fixture, the Corvus macrorhuchus mouth that described check valve comprises cylindrical portion and is positioned at this cylindrical portion one side, described Corvus macrorhuchus the mouth gradually flat and anti-reverse valve structure of symmetric wedge shape that forms in these cylindrical portion front end both sides of serving as reasons, the anti-reverse valve structure front end of described wedge shape is rectangle section or approximate rectangle section, described section has the valve port of the wire centre joint along its length direction, it is characterized in that: described check valve also comprises an extension fixture, and described extension fixture comprises that a pair of check valve that is arranged at is inboard and be positioned at described valve port two ends and can drive this valve port with its columnar part that expands outwardly.

2. a kind of check valve that includes extension fixture as claimed in claim 1 is characterized in that: described two columnar parts are along the setting of check valve axially parallel and only expand outwardly at front end position separately.

3. a kind of check valve that includes extension fixture as claimed in claim 2 is characterized in that: its section of described columnar part is a triangle.

4. a kind of check valve that includes extension fixture as claimed in claim 3 is characterized in that: its inboard, described front end position is convergence laterally gradually.

5. a kind of check valve that includes extension fixture as claimed in claim 1 is characterized in that: the anti-reverse valve of described wedge shape has the interior lateral surface of different angle, and its medial surface inclination angle is slightly less than the lateral surface inclination angle.

6. a kind of check valve that includes extension fixture as claimed in claim 5 is characterized in that: its lateral surface of the anti-reverse valve of described wedge shape is made up of two planes of different angle, and wherein its inclination angle, plane of close valve port is less than the planar inclination angle away from valve port.

7. extension fixture as claimed in claim 1 is characterized in that: described extension fixture comprises that a pair of check valve that is arranged at is inboard and be positioned at its valve port two ends and can drive this valve port with its columnar part that expands outwardly and in order to fix the installation portion of this columnar part.

8. extension fixture as claimed in claim 7 is characterized in that: described two columnar parts are along the setting of check valve axially parallel and only expand outwardly at front end position separately.

9. extension fixture as claimed in claim 8 is characterized in that: its section of described columnar part is that triangle and its front end position converge wedge-like laterally.

10. extension fixture as claimed in claim 7 is characterized in that: described installation portion is a cylindrical structure and suitable with the cylindrical portion inboard of described check valve.

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