CN215875547U

CN215875547U - Dispensing syringe with built-in vent groove

Info

Publication number: CN215875547U
Application number: CN202120420591.3U
Authority: CN
Inventors: 宋少岩; 俞志平
Original assignee: Meilan Hangzhou Pharmaceutical Technology Co ltd
Current assignee: Meilan Hangzhou Pharmaceutical Technology Co ltd
Priority date: 2020-09-10
Filing date: 2021-02-26
Publication date: 2022-02-22
Anticipated expiration: 2031-02-26
Also published as: CN112915012A

Abstract

The utility model provides a dispensing injector with a built-in vent groove, which comprises an injection tube and a needle tube. The injection tube comprises a main body part for containing liquid medicine and an extension part connected with the main body part, the extension part is provided with a channel communicated with the main body part, the extension part is provided with a first air hole close to the main body part and a second air hole far away from the main body part, and the inner wall of the extension part is provided with a vent groove extending from the position of the first air hole to the position of the second air hole; one end of the needle tube is provided with a puncture needle point, the other end of the needle tube is embedded into the extending part so that the needle tube is fixed in the channel, the needle point is exposed out of the extending part, when dispensing, the needle point of the needle tube is placed into the liquid medicine bottle by the dispensing mechanical arm, the second air hole enters the liquid medicine bottle and is not contacted with the liquid medicine, and the first air hole is arranged outside the liquid medicine bottle; the core bar is movably arranged in the inner cavity of the injection tube, one end of the core bar is provided with a piston, and the other end of the core bar is provided with a holding part matched with the push-pull device. According to the utility model, the liquid medicine pollution can be reduced and the medicine dispensing efficiency can be improved.

Description

Dispensing syringe with built-in vent groove

Technical Field

The utility model particularly relates to a dispensing injector with a built-in vent groove.

Background

With the development of science and technology, mechanical automation is gradually applied to various fields, for example, when dispensing medicines, a medicine dispensing mechanical arm and a medicine dispensing injector can be used for dispensing medicines, so that the labor input is reduced.

At present, a dispensing injector used in cooperation with a dispensing mechanical arm is generally formed by combining a split type injection tube and a needle tube, and the injection tube and the needle tube are connected through an adhesive. When a medicine is dispensed using such a split type dispensing syringe, an adhesive for connecting the syringe and the needle tube may react with the liquid medicine when contacting the liquid medicine, and the liquid medicine may be contaminated. In addition, the liquid medicine bottle usually has pressure difference inside and outside the bottle, so that the liquid medicine may be splashed or difficult to be sucked by the syringe due to abnormal air pressure difference inside and outside the bottle during the process of sucking the liquid medicine, thereby causing low dispensing efficiency.

SUMMERY OF THE UTILITY MODEL

The present invention has been made in view of the above situation, and an object thereof is to provide a dispensing syringe with an internal vent groove, which can reduce contamination of a drug solution and improve dispensing efficiency.

A first aspect of the present invention provides a dispensing syringe, comprising: the injection tube comprises a main body part for containing liquid medicine and an extension part connected with the main body part, wherein the extension part is provided with a channel communicated with the main body part, the extension part is provided with a first air hole close to the main body part and a second air hole far away from the main body part, and the inner wall of the extension part is provided with a vent groove extending from the position of the first air hole to the position of the second air hole; the needle tube is provided with a puncture needle point at one end, the other end of the needle tube is embedded into the extension part, the needle tube is fixed in the channel by forming a fixing part between the insert injection molding and the channel, the main body part forms an injection passage with the needle tube through the channel, the fixing part is positioned between the first air hole and the second air hole, and the needle point is exposed out of the extension part; and the core bar is movably arranged in the inner cavity of the injection tube, one end of the core bar is provided with a piston, the other end of the core bar is provided with a rod body used for pushing and pulling, when dispensing, the needle tube is placed in the liquid medicine bottle, the second air hole enters the liquid medicine bottle and is not contacted with the liquid medicine, and the first air hole does not enter the liquid medicine bottle.

In the dispensing syringe according to the present invention, the passage is provided between the main body portion and the extension portion of the syringe, and the fixing portion is formed between the needle tube and the passage by insert injection to fix the needle tube to the passage, whereby contamination of the liquid medicine can be reduced. In addition, the extension part is provided with a first air hole close to the main body part and a second air hole far away from the main body part, the inner wall of the extension part is provided with a vent groove extending from the position of the first air hole to the position of the second air hole, and when dispensing, the needle tube is placed in the liquid medicine bottle, the second air hole enters the liquid medicine bottle, and the first air hole does not enter the liquid medicine bottle. In this case, the first air hole located outside the liquid medicine bottle and the second air hole located inside the liquid medicine bottle balance the difference in air pressure between the inside and the outside of the liquid medicine bottle, so that the liquid medicine can be easily extracted or pushed, and the dispensing efficiency can be improved.

In the dispensing syringe according to the first aspect of the present invention, a through hole may be provided between the main body portion and the extension portion, and the main body portion may communicate with the channel via the through hole.

In the dispensing syringe according to the first aspect of the present invention, the dispensing syringe may further include a drug solution filtering membrane provided between the main body portion and the extending portion. This enables the filtration of the chemical solution.

In the dispensing syringe according to the first aspect of the present invention, the needle tube may be fitted into one end of the extension portion and connected to the through hole such that the main body portion and the needle tube form an injection passage. This allows the drug solution to enter the body through the needle tube.

In the dispensing syringe according to the first aspect of the present invention, the extension portion may be integrally formed continuously with the main body portion. This can prevent the extension portion and the body portion from being separated from each other when the dispensing syringe is operated.

In the dispensing syringe according to the first aspect of the present invention, the dispensing syringe may further include a gas filtration membrane provided in the first gas hole. This enables air to be filtered.

In the dispensing syringe according to the first aspect of the present invention, the length of the needle tube is longer than the length of the extension portion, and the length of the needle tube protruding from the extension portion is longer than the height of the liquid medicine in the liquid medicine bottle so that the second air hole does not contact the liquid medicine. In this case, when the dispensing syringe is operated, the air pressure inside and outside the liquid medicine bottle can be balanced by the first air hole and the second air hole.

In the dispensing syringe of the first aspect of the present invention, the passage may optionally taper in internal diameter from proximal to distal to the body portion. Thereby, the inner diameter of the channel can be matched with the needle tube by tapering.

In the dispensing syringe according to the first aspect of the present invention, the first air hole may have a size larger than that of the second air hole.

In the dispensing syringe according to the first aspect of the present invention, the outer wall of the body portion may be transparent. This facilitates the external observation of the liquid medicine contained in the cavity.

According to the present invention, it is possible to provide a dispensing syringe with an internal vent groove that can reduce contamination of a drug solution and improve dispensing efficiency.

Drawings

Fig. 1 is a schematic diagram showing the cooperation of a dispensing syringe with an internal vent groove and a dispensing robot according to an embodiment of the present invention.

Fig. 2 is a schematic perspective view of a dispensing syringe with an internal vent groove according to an embodiment of the present invention.

Fig. 3 is a schematic cross-sectional view of a dispensing syringe with an internal vent groove according to an embodiment of the present invention, taken along the longitudinal direction.

Fig. 4 is a partially enlarged schematic view of the extension of fig. 3.

Fig. 5 is a schematic view of a liquid medicine bottle containing a dispensing syringe with an internal vent groove according to an embodiment of the present invention.

Description of reference numerals:

10 … dosage injector, 110 … syringe, 111 … main body part, 1110 … inner cavity, 1111 … cover body, 1112 … through hole, 1113 … liquid medicine filter membrane, 112 … extending part, 1120 … channel, 1121 … first air hole, 1122 … second air hole, 1123 … vent groove, 1124 … gas filter membrane, 1125 … fixed part, 1126 … reinforcing rib, 120 … needle tube, 121 … needlepoint, 130 … core rod, 131 … rod body, 132 … piston, 20 … dosage mechanical arm, 210 … clamping device, 220 … push-pull device, 230 … loading device, 30 … liquid medicine bottle

Detailed Description

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same components are denoted by the same reference numerals, and redundant description thereof is omitted. The drawings are schematic and the ratio of the dimensions of the components and the shapes of the components may be different from the actual ones.

The present embodiment relates to a dispensing syringe, and the dispensing syringe with an internal vent groove may be simply referred to as a dispensing syringe or a syringe. The dispensing syringe of the present embodiment can improve dispensing efficiency and reduce contamination of liquid medicine. The dispensing syringe according to the present embodiment will be described in detail below with reference to the drawings.

Fig. 1 is a schematic diagram illustrating the engagement of a dispensing syringe 10 and a dispensing robot 20 according to an embodiment of the present invention. Fig. 2 is a schematic perspective view of the dispensing syringe 10 according to the embodiment of the present invention. Fig. 3 is a schematic sectional view of the dispensing syringe 10 according to the embodiment of the present invention along the longitudinal direction.

In the present embodiment, the injector 10 may include a syringe 110 and a needle tube 120 (see fig. 1 and 2). In some examples, the syringe 10 may further include a core pin 130 (see fig. 1 and 2).

The dispensing robot 20 may include a gripping device 210, a push-pull device 220, and a loading device 230. The holding unit 210 may hold the syringe 110 of the syringe 10, the push-pull unit 220 may push-pull the stem 130 of the syringe 10, and the loading unit 230 may load the liquid medicine bottle 30 (see fig. 1) containing the liquid medicine.

In this embodiment, the dispensing robot 20 may grip the syringe 10 by the gripping device 210 and may push and pull the core pin 130 of the syringe 10 by the push-pull device 220. In addition, the syringe 10 held on the holding unit 210 may have a position corresponding to the loading unit 230 for loading the liquid medicine bottle 30, and the holding unit 210 of the dispensing robot 20 may be moved in the a direction to enter the syringe 120 of the syringe 10 into the liquid medicine bottle 30, and the holding unit 210 may also be moved in the b direction to leave the syringe 120 of the syringe 10 from the liquid medicine bottle 30 (see fig. 1).

In this embodiment, the injector 10 may include a syringe 110 and a syringe 120, as described above. In some examples, syringe 10 may also include a core pin 130. Wherein the syringe 110 and the needle tube 120 may form an injection passage, the core pin 130 may be movably disposed in an inner cavity 1110 (described later) of the syringe 110, and the injector 10 may push or suck a medical fluid through the needle tube 120 and the injection passage by pushing or pulling the core pin 130.

In some examples, syringe 110 may include a body portion 111 and an extension portion 112 (see fig. 2). The main body 111 may be formed with an inner cavity 1110 for receiving a medical solution, and the extension part 112 may be connected to the main body 111.

In some examples, the body portion 111 may be elongated. For example, the outer contour of the body 111 may have a columnar structure such as a cylindrical shape or a prismatic shape.

In some examples, as described above, the body portion 111 may have an internal cavity 1110, and the internal cavity 1110 may be used to contain a medical fluid. In some examples, the diameter may be the same throughout the lumen 1110. Thereby, the core bar 130 can be easily pushed or pulled within the internal cavity 1110.

In some examples, the main body 111 may be made of plastic or the like. For example, the material of the main body 111 may be polypropylene or polyvinyl chloride. However, the present invention is not limited to this example, and the main body 111 may be made of other materials, such as glass.

In some examples, the body portion 111 may be transparent. This facilitates the external observation of the medical fluid contained in the internal cavity 1110. In some examples, the outer wall of the main body 111 may be provided with a scale (not shown). In some examples, the scale on the outer wall of the main body portion 111 may increase in order from the end near the extension portion 112 to the end far from the extension portion 112. For example, 5ml, 10ml, 15ml, 20ml, 25ml, 30 ml. This facilitates reading of the amount of the chemical liquid in the main body 111.

In some examples, an end of the main body 111 distal from the extension 112 may be provided with a cover 1111. In this case, the holder 210 can restrain the syringe 10 from sliding on the holder 210 by holding the lid 1111 (see fig. 1). In some examples, the cover 1111 may protrude outward from the main body portion 111 in a radial direction of the main body portion 111.

In some examples, an end of the body portion 111 near the extension 112 may be provided with a through hole 1112. The body portion 111 may communicate with the extension portion 112 through a through hole 1112.

In some examples, the extension 112 may be continuously integrally formed with the body portion 111. This can prevent the extension portion 112 and the body portion 111 from being separated from each other when the dispensing syringe 10 is operated. But the example of the present invention is not limited thereto, and the extension part 112 may be connected with the main body part 111 in other ways. The extension portion 112 is connected to the main body portion 111 by, for example, adhesion, screwing, or engagement.

In some examples, the extension 112 may be elongated. In some examples, the outer diameter of the extension 112 may taper from an end proximal to the body 111 to an end distal to the body 111. For example, the extension 112 may be generally conical. Thereby facilitating entry of the extension 112 into the liquid medicine bottle 30.

In some examples, the extension 112 may have a stiffener 1126, and in some examples, the stiffener 1126 may be located on an outer wall of the extension 112 proximate the body portion 111. In some examples, there may be four reinforcing ribs 1126. This makes it possible to make the extension portion 112 less likely to separate from the main body portion 111.

In some examples, the extension 112 may have a channel 1120 running through it lengthwise. In some examples, the channel 1120 may be tapered. That is, the inner diameter of the channel 1120 may gradually decrease from an end close to the body portion 111 to an end far from the body portion 111. But examples of the present invention are not limited thereto and the channel 1120 may have other shapes. For example, the channel 1120 may be cylindrical, etc. In some examples, when the extension 112 is connected with the body portion 111, the channel 1120 may be in communication with the lumen 1110 of the body portion 111. In some examples, the inner diameter of the channel 1120 near an end of the body portion 111 may be equal to the inner diameter of the lumen 1110 of the body portion 111 near an end of the extension 112. Additionally, in some examples, the lumen 1110 of the body portion 111 may communicate with the channel 1120 of the extension 112 via the through-holes 1112 of the body portion 111.

In some examples, a drug solution filtering membrane 1113 (see fig. 3) may be disposed between the extension portion 112 and the body portion 111. In some examples, the drug solution filtering membrane 1113 may include a large number of filtering holes. In this case, when the chemical enters the extension part 112 from the main body part 111, impurities in the chemical can be filtered effectively by the chemical filtering membrane 1113.

In some examples, the drug solution filtering membrane 1113 may be disposed in the through hole 1112 of the main body 111. In some examples, the drug solution filter membrane 1113 may be no smaller than the through-hole 1112. In some examples, the drug solution filter 1113 may fill the through hole 1112. In some examples, the drug solution filtering membrane 1113 may cover the through hole 1112. Thus, impurities in the liquid medicine can be effectively filtered.

In some examples, the drug solution filtering membrane 1113 may be fixed between the main body 111 and the extension 112 by a snap or screw method. For example, the liquid medicine filtering membrane 1113 may include a filter screen (not shown) and a housing (not shown) for carrying the filter screen, and the housing may have a snap-fit structure or a screw-fit structure. In this case, the chemical filtering membrane 1113 may be fixed between the main body 111 and the extension 112 by engagement or screwing. However, the present invention is not limited thereto, and in some examples, the medical fluid filtering membrane 1113 may be fixed between the main body 111 and the extension portion 112 by other methods, for example, the medical fluid filtering membrane 1113 may be fixed by adhesion.

Fig. 4 is a partially enlarged schematic view of the extension 112 of fig. 3.

In some examples, the extension 112 is integrally formed with the body 111. In some examples, the extension part 112 and the main body part 111 of the injection tube 110 can be integrally molded by injecting plastic in a molten state into a mold cavity through an insert injection molding process and cooling the injection tube 110.

In some examples, the extension 112 may have a first air hole 1121 and a second air hole 1122. In some examples, the inner wall of the extension 112 may be provided with a vent groove 1123 (see fig. 4) extending from the position of the first air hole 1121 to the position of the second air hole 1122. Thus, the first air hole 1121 and the second air hole 1122 can communicate through the vent groove 1123.

In some examples, the extension 112 may partially enter the liquid medicine bottle 30. Specifically, when the extension enters the liquid medicine bottle 30, the first air hole 1121 may be located outside the liquid medicine bottle 30 and the second air hole 1122 may be located inside the liquid medicine bottle 30. In this case, the liquid medicine bottle 30 is communicated with the atmosphere through the first air hole 112, the second air hole 1122 and the air vent 1123, and the air pressures inside and outside the liquid medicine bottle 30 can be balanced, so that the problems of the liquid medicine being splashed or the liquid medicine being difficult to be sucked into the syringe 10 due to the abnormal air pressure difference inside and outside the bottle during the liquid medicine suction process can be effectively prevented. This can improve the dispensing efficiency.

In some examples, the first air holes 1121 and the second air holes 1122 may be disposed on an outer wall of the extension 112. In some examples, the first air holes 1121 may be closer to the body portion 111 than the second air holes 1122 (see fig. 2 and 3). But the example of the present invention is not limited thereto and the extension 112 may be provided with three or more air holes.

In some examples, the first air holes 1121 may be circular in shape. However, examples of the present invention are not limited thereto, and in some examples, the shape of the first air holes 1121 may also be a regular shape such as a square, a triangle, or an irregular shape. In some examples, the second air holes 1122 may be circular or square in shape. However, examples of the present invention are not limited thereto, and in some examples, the second air holes 1122 may have a regular shape such as a square, a triangle, or an irregular shape.

In some examples, the size of the first air holes 1121 may be no smaller than the size of the second air holes 1122. In some examples, the first gas apertures 1121 may be provided with a gas filtering membrane 1124 (see fig. 4) that filters gas. In this case, the gas filtering membrane 1124 prevents air from contaminating the liquid medicine.

In some examples, the shape of the gas filtration membrane 1124 may be the same as the shape of the first gas apertures 1121, and the area of the gas filtration membrane 1124 may be slightly larger than the area of the first gas apertures 1121. In some examples, the gas filtering membrane 1124 may be fixed to and cover the first gas hole 1121 by welding or bonding.

In some examples, gas filtration membrane 1124 may be provided with a plurality of vent holes (not shown) that are evenly distributed. Thus, the difference in air pressure between the inside and the outside of the liquid medicine bottle 30 can be rapidly balanced. In some examples, gas filtration membrane 1124 can be a multi-layer structure. This enables air to be filtered more efficiently.

In the present embodiment, as described above, the injector 10 may include the syringe 120 (see fig. 2). In some examples, needle cannula 120 may be embedded in extension 112. In some examples, one end of needle cannula 120 distal to extension 112 may have a piercing needle tip 121 and the other end may be embedded in extension 112 (see fig. 3).

In some examples, needle cannula 120 may be inserted into passage 1120 of extension 112. In some examples, the plastic part in a molten state is coated on the outer circumference of the needle tube 120 by insert injection molding, so that the needle tube 120 can form a fixing portion 1125 with the channel 1120 of the extension portion 112 to be fixed to the channel 1120 (see fig. 4). Thus, contamination of the chemical solution can be reduced.

In some examples, a retainer 1125 may be formed between the needle cannula and the channel 1120, and the needle cannula 120 may be secured to the channel 1120 by the retainer 1125. In some examples, retainer 1125 may be formed by cooling molten plastic between needle 120 and extension 112 by insert molding. In some examples, the fixation portion 1125 may be located on an inner wall of the extension 112. In some examples, the fixation portion 1125 may be located between the first air aperture 1121 and the second air aperture 1122. In some examples, the vent groove 1123 may be located on the fixing portion 1125, and the gas inside and outside the liquid medicine bottle 30 may flow on the vent groove 1123 of the fixing portion 1125, thereby balancing the pressure difference inside and outside the liquid medicine bottle 30.

In some examples, body portion 111 may form an injection path with needle 120 via channel 1120. In some examples, the end of needle cannula 120 inserted into extension 112 may be connected to through-hole 1112 of body 111, thereby enabling an injection path with body 111 via channel 1112. In some examples, the end of the needle 120 inserted into the extension 112 may abut against the through hole 1112 of the body 111. In other examples, the end of the needle tube 120 inserted into the extension 112 may be connected to the through hole 1112 of the main body 111 by, for example, a connecting tube (not shown).

Fig. 5 is a schematic view showing the dispensing syringe 10 according to the embodiment of the present invention being placed in the liquid medicine bottle 30.

In some examples, the syringe 10 may enter the liquid medicine bottle 30 by the needle tip 121 of the needle cannula 120 piercing, for example, a closure of the liquid medicine bottle 30. In some examples, the length of needle cannula 120 may be no less than the length of extension 112. In this case, the needle tube 120 can be fitted into the extension 112 so as to come into contact with the through hole 1112 of the body 111. Examples of the present invention are not limited thereto and the length of needle cannula 120 may be less than the length of extension 112. In some examples, the length from the second air hole 1122 to the needle tip 121 is not less than the height of the liquid medicine in the liquid medicine bottle 30, so that the second air hole 1122 is not in contact with the liquid medicine in the liquid medicine bottle 30.

In some examples, the first air vent 1121 and the second air vent 1122 may be configured in such positions that the first air vent 1121 does not enter the liquid medicine bottle 30 and the second air vent 1122 may not contact the liquid medicine in the liquid medicine bottle 30 after the needle tube 120 enters the liquid medicine bottle 30 (see fig. 5). In this case, when the dispensing syringe 10 is operated, the first air hole 1121 and the second air hole 1122 are positioned outside and inside the liquid medicine bottle 30, respectively, and the second air hole 1122 is not in contact with the liquid medicine in the liquid medicine bottle 30, so that the liquid medicine bottle 30 can be in air communication with the atmosphere, and the air pressures inside and outside the liquid medicine bottle 30 can be balanced.

In some examples, as described above, the syringe 10 may also include a core pin 130 (see fig. 2). In some examples, the mandrel 130 may be disposed within the internal cavity 1110 of the body portion 111 and may be movable within the internal cavity 1110. In this case, when the needle tube 120 is inserted into the liquid medicine bottle 30 and the needle tip 121 is immersed in the liquid medicine bottle 30, the syringe 10 can push or suck the liquid medicine in the liquid medicine bottle 30 by pushing or pulling the stem 130 (see fig. 1). Specifically, when the stem 130 is pushed, the drug solution can be pushed from the inner cavity 1110 of the body 111 into the drug solution bottle 30 through the injection passage formed by the body 111 and the needle tube 120; when the stem 130 is pulled, the drug solution can be sucked from the drug solution bottle 30 into the cavity 1110 of the body 111 through the injection path formed by the body 111 and the needle tube 120.

In some examples, the stem 130 may include a shaft 131 and a plunger 132, and the plunger 132 may be disposed at an end of the shaft 131 near the needle 120 (see fig. 3).

In some examples, the shaft 131 may be elongated. In some examples, the outer diameter of the shaft 131 may be no greater than the diameter of the inner cavity 1110 of the body portion 111. In some examples, the length of the shaft 131 may be no less than the length of the inner cavity 1110 of the body portion 111.

In some examples, piston 132 may have an outer diameter that matches the inner cavity 1110 of body portion 111 to enable piston 132 to move along the walls of inner cavity 1110. In some examples, the piston 132 may be made of an elastic material.

In some examples, the piston 132 may be integrally formed with the rod 131. In other examples, the piston 132 may be coupled to the rod 131 by a snap-fit. However, the present invention is not limited thereto, and the rod 131 may be connected to the piston 132 in other manners. The rod 131 is coupled to the piston 132, for example, by bonding, screwing, or the like.

In some examples, the core pin 130 may also be composed of a piston 132, and the push-pull device 220 may be an air pump device (not shown). In this case, the air pump device is connected to the inner cavity 1110 of the main body 111, and the air pressure in the inner cavity 1110 is increased by the air pump device to push the piston 132 in a direction approaching the needle tube 120, thereby pushing the liquid medicine; the medical fluid can be sucked by reducing the air pressure in the inner cavity 1110 by the air pump means to pull the piston 132 in a direction away from the needle tube 120.

While the utility model has been specifically described above in connection with the drawings and examples, it will be understood that the above description is not intended to limit the utility model in any way. Those skilled in the art can make modifications and variations to the present invention as needed without departing from the true spirit and scope of the utility model, and such modifications and variations are within the scope of the utility model.

Claims

1. A dispensing syringe with a built-in vent groove is characterized by comprising:

the injection tube comprises a main body part for containing liquid medicine and an extension part connected with the main body part, wherein the extension part is provided with a channel communicated with the main body part, the extension part is provided with a first air hole close to the main body part and a second air hole far away from the main body part, and the inner wall of the extension part is provided with a vent groove extending from the position of the first air hole to the position of the second air hole;

the needle tube is provided with a puncture needle point at one end, the other end of the needle tube is embedded into the extension part, the needle tube is fixed in the channel by forming a fixing part between the insert injection molding and the channel, the main body part forms an injection passage with the needle tube through the channel, the fixing part is positioned between the first air hole and the second air hole, and the needle point is exposed out of the extension part; and

a core bar movably arranged in the inner cavity of the injection tube, wherein one end of the core bar is provided with a piston, the other end is provided with a rod body for pushing and pulling,

when dispensing, the needle tube is placed in a liquid medicine bottle, the second air hole enters the liquid medicine bottle and is not in contact with the liquid medicine, and the first air hole does not enter the liquid medicine bottle.

2. A dispensing syringe according to claim 1, wherein:

a through hole is formed between the main body part and the extending part, and the main body part is communicated with the channel through the through hole.

3. A dispensing syringe according to claim 2, wherein:

the dispensing syringe with the built-in vent groove further comprises a liquid medicine filtering membrane arranged between the main body part and the extension part.

4. A dispensing syringe according to claim 2, wherein:

the needle tube is embedded in one end of the extending part and is connected with the through hole, so that the main body part and the needle tube form an injection passage.

5. A dispensing syringe according to claim 1, wherein:

the extension portion is continuously integrally formed with the main body portion.

6. A dispensing syringe according to claim 1, wherein:

the dispensing injector with the built-in vent groove further comprises a gas filtering membrane arranged at the first air hole.

7. A dispensing syringe according to claim 1, wherein:

the length of the needle tube is longer than that of the extension part, and the length of the needle tube protruding from the extension part is longer than the height of the liquid medicine in the liquid medicine bottle so that the second air hole is not in contact with the liquid medicine.

8. A dispensing syringe according to claim 1, wherein:

the passage has an inner diameter that decreases from proximate the body portion to distal the body portion.

9. A dispensing syringe according to claim 1, wherein:

the first air hole has a size larger than that of the second air hole.

10. A dispensing syringe according to claim 1, wherein:

the outer wall of the body portion is transparent.