CN111773483A - Self-destruction syringe capable of quantitatively drawing liquid - Google Patents

Abstract

The patent relates to the technical field of syringes, and particularly discloses a self-destruction syringe capable of quantitatively drawing liquid, which comprises a cylinder body, a locking component and a core rod component, wherein the core rod component comprises a plug body, a user push rod, an extension body part and a groove arranged along the extension body part, a plurality of first teeth are arranged in the groove, and the first teeth form a plurality of shoulders; the core rod assembly can be inserted into the cylinder body; a locking member positionable within the groove, the locking member including a body portion including a first wall and a second wall connected along a longitudinal axis and extending radially; also included is a first leg and a second leg, at least one of the legs including a pull-out end having a first barb extending from an outer edge of the pull-out end for engaging an inner surface of the barrel to prevent the locking member from sliding in the pull-out direction. This patent makes the syringe wholly destroyed through a motion to avoid syringe part by reuse.

Description

Self-destruction syringe capable of quantitatively drawing liquid

Technical Field

The invention relates to the technical field of injectors, in particular to a self-destruction injector capable of quantitatively drawing liquid.

Background

Syringe reuse has always been a significant potential in medical treatment worldwide, and the intravenous toxicant population who normally shares and reuses syringes is also a high-risk population of aids, and every year, people become infected with aids virus because of the shared and reused syringes. In addition, in many developing countries, patient life-threatening events are frequent and alarming due to viral cross-contamination among people caused by the repeated use of syringes.

A large number of syringes have been designed in the prior art to address this problem. Some require a specific action to destroy the syringe after use, either by using a destructive device or by providing the syringe with a frangible zone to render it unusable by external force. These areas of weakness are often found on pushers used to push fluids, which can be broken off by force, but do not cause any damage to the barrel of the injector, which can be reused after a plunger has been reattached.

Disclosure of Invention

The invention aims to provide a self-destruction injector capable of quantitatively drawing liquid, which can not be reused through one action, so as to solve the technical problem that a part of a syringe can be left undamaged after the self-destruction injector is damaged once in the prior art, and the syringe can still be partially reused.

The self-destruction syringe capable of quantitatively drawing liquid comprises a cylinder body, a locking component and a mandrel component, wherein the mandrel component comprises a plug body, a user push rod, an extension body part and a groove arranged along the extension body part, a plurality of first teeth are arranged in the groove, and the first teeth form a plurality of shoulders facing the pushing direction of the user push rod;

the core rod assembly can be inserted into the cylinder body;

the locking member is positionable within the recess, the locking member including a body portion;

the body portion includes a first wall and a second wall connected along a longitudinal axis and extending radially;

further comprising first and second legs extending from the first and second walls, respectively, in a pull-out direction of the user putter, wherein at least one of the legs includes a pull-out end portion facing in the pull-out direction of the user putter and engageable with the shoulder portion, the pull-out end portion having a first barb portion extending radially outwardly from an outer edge thereof;

a tip of the first barb portion inclined to the pull-out direction for engaging with an inner surface of a barrel to prevent the lock member from sliding in the pull-out direction;

the first teeth are distributed between one end of the groove close to the pull-out direction and the axial middle point of the groove.

Further, the outer edges of the first leg and the second leg are provided with the first barb portions.

Further, the two first barb parts are arranged symmetrically left and right around the longitudinal axis.

Further, a second barb extends radially outwardly from an outer edge of at least one of the first and second walls, a tip of the second barb being inclined in the pull-out direction for engaging an inner surface of the barrel to prevent the locking member from sliding in the pull-out direction.

Further, the outer edges of the first wall and the second wall are provided with the second barb parts respectively.

Further, the two second barb parts are arranged symmetrically left and right around the longitudinal axis.

Further, a gap is left between the first leg and the second leg.

Further, the first and second legs flare outwardly from their connection to the first and second walls.

Further, the locking member is a sheet member made of a metal plate material having elasticity, and a protrusion is provided on a surface thereof.

Furthermore, the user push rod and the extension body part are integrally formed on the core rod assembly, and a connecting part which is easy to break is arranged between the user push rod and the extension body part.

Embodiments of the present invention may provide a simple, reliable, easy to manufacture, single use syringe that may become non-reusable without any additional action by the user, using a locking member that cannot be retracted with the plunger rod assembly; meanwhile, the maximum distance that the core rod assembly can retract is changed by utilizing the initial position of the locking component during installation or selecting which group of first teeth the locking component is meshed with, so that quantitative liquid drawing of different doses can be realized, excessive liquid drawing for accurately obtaining the doses is not needed, and redundant doses are wasted.

And some embodiments of the present invention provide a connection that is easily snapped, allowing the mandrel assembly to break when additional force is applied by the user, resulting in further self-destruction.

Drawings

Fig. 1 is an exploded view of a self-destructive syringe capable of quantitatively drawing liquid in an embodiment of the present invention.

FIG. 2 is a front view of the core rod assembly of FIG. 1.

Fig. 3a is a front view of the locking member of fig. 1.

Fig. 3b is a top view of the locking member of fig. 1.

Fig. 4a is a structural schematic diagram of a self-destructive injector capable of quantitatively drawing liquid in an embodiment of the invention before use.

Fig. 4b is a schematic structural diagram of the self-destructive injector capable of quantitatively drawing liquid after drawing liquid in the embodiment of the invention.

Fig. 4c is a schematic structural diagram of the self-destructive injector capable of quantitatively drawing liquid in the embodiment of the invention after use.

Reference numerals in the drawings of the specification include: the plunger assembly 1, the barrel 2, the locking member 3, the protective sheath 4, the needle hub 21, the puncture needle tube 211, the plug body 5, the user push rod 11, the extension body part 12, the middle disc 121, the plunger head 13, the button 14, the groove 15, the first tooth 16, the shoulder 161, the notch 17, the first wall 31, the second wall 32, the first leg 33, the second leg 34, the pull-out end 331, the first barb 332, the second barb 311 and the protrusion 341.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The self-destructive syringe capable of drawing liquid quantitatively in the present invention is basically as shown in fig. 1, and comprises a protective sheath 4, a cylinder 2, a locking member 3 and a core rod assembly 1.

The barrel 2 in this embodiment is similar to the barrels of most syringes and is used for containing liquid medicine, one end of the barrel 2 is an open end, the other end is a closed end, and a bead extends outwards from the opening of the open end, so that a user can operate and hold the syringe conveniently.

Still integrated into one piece has needle file 21 on the terminal surface of blind end, and is the same as ordinary syringe needle, be provided with the puncture needle pipe 211 with barrel 2 internal intercommunication on the needle file 21 along the axis of barrel 2, and this type of integrated into one piece's needle file 21 and puncture needle pipe 211 wherein are comparatively common in prior art, do not do the repeated description here. In alternative embodiments, a hub 21 and piercing needle 211 that are separable from barrel 2, as is common in the art, may also be used.

The mandrel assembly 1 includes a plug body 5, a user push rod 11, an elongated body portion 12, and a recess 15 disposed along the elongated body portion 12; the end of the extension body 12 is formed with a core rod 13, and the plug body 5 can be fitted over the core rod 13.

As shown in fig. 2, the body portion 12 includes a pair of intermediate disks 121 formed at both ends of the body portion 12. The portion between the two intermediate disks 121 extends outwards with vanes which form the aforementioned recesses 15. The side walls of the blades within the recess 15 are formed with a plurality of first teeth 16, each of the first teeth 16 being a ratchet tooth, each first tooth 16 including a shoulder 161 facing in the advancing direction and a ramp extending obliquely downward from the shoulder 161. In this embodiment, the portion of the user's putter 11 between the pressing hand 14 and the intermediate plate 121 has the same shape as the elongated body portion 12, except that the first teeth 16 are absent; in addition, the first teeth 16 are distributed only on a portion between the intermediate disk 121 in the pull-out direction within the recess 15 and the midpoint in the axial direction of the recess 15. A connecting portion which is easy to be broken is provided between the user pushing rod 11 and the extension body portion 12, specifically, as shown in fig. 2, a portion of each blade on one side of the user pushing rod 11, which is close to the intermediate disc 121, is recessed toward the central axis direction of the core bar assembly 1 to form a notch 17, thereby reducing the cross-sectional area of the core bar assembly 1, more specifically, the cross-sectional area of the user pushing rod 11 portion is reduced in this embodiment. A push handle 14 is formed at an end of the user push rod 11 pointing in the pulling direction thereof to facilitate a user's force to push and pull the core bar assembly 1.

The locking member 3 can be positioned in the recess 15. how the entire core rod assembly 1 can be inserted into the barrel 2 from the open end, the recess 15 serves as a passage for longitudinal movement of the locking member 3 relative to the elongated body portion 12.

As shown in fig. 3, the locking member 3 comprises a body portion comprising, connected along a longitudinal axis and extending radially, a first wall 31 and a second wall 32; a first leg 33 and a second leg 34 extending from the first and second walls 32 in the pulling direction of the user push rod 11, respectively, each leg having a pulling end 331 facing in the pulling direction and engageable with the shoulder 161 of the first tooth 16, the two pulling ends 331 each having a first barb 332 extending radially outward from an outer edge thereof, the two first barbs 332 being arranged symmetrically left and right about the longitudinal axis; the tip of the first barb 332 is inclined to the pull-out direction for engaging with the inner surface of the cylinder 2 to prevent the lock member 3 from sliding in the pull-out direction.

Preferably, in the present embodiment, the outer edges of the first wall 31 and the second wall 32 are also extended with the second barb portions 311 radially outward, and the two second barb portions 311 are also arranged in the tip inclined pull-out direction of the second barb portions 311 symmetrically left and right around the longitudinal axis, so as to further enhance the engagement of the locking member 3 with the inner surface of the cylinder 2, so as to prevent the locking member 3 from sliding in the pull-out direction.

As can be seen from fig. 3a, a gap is left between the first leg 33 and the second leg 34, and the first leg 33 and the second leg 34 flare outwards from their connection with the first wall 31 and the second wall 32.

The locking member 3 may be a sheet member made of a resilient metal plate, and the locking member 3 in this embodiment is preferably made of a thin metal plate (e.g., stainless steel). The size of the locking member 3 is selected according to the barrel 2 and core rod assembly 1 used. The angle between the two halves of the locking part 3 in this embodiment is about 90 degrees, and most preferably may be about 100 degrees. When installed in one of the grooves 15 of the core rod assembly 1, the locking member 3 will exert a corresponding force against both side walls of the groove 15. Therefore, even after the locking member 3 is mounted, a gap remains between the first leg 33 and the second leg 34. This clearance is maintained to act as a cantilever spring so that the force on the barrel 2 is relatively reduced to facilitate use and installation of the locking device within the injection sheath. As can be seen from fig. 3a, a hemispherical protrusion 341 is formed on the surface of the second leg 34, and in this embodiment, the protrusion 341 is formed by stamping, and the protrusion 341 can prevent the locking parts 3 from completely fitting when a plurality of locking parts 3 are stacked at one time, so that a gap is left, and the single locking part 3 can be conveniently taken out from the stacked locking parts 3 for assembly in actual production. In other embodiments, the orientation and specific location of the protrusion 341 is not the same as in the present embodiment, but may serve the same purpose. As can be seen in fig. 3a and b, the first wall 31, the second wall 32, the first leg 33 and the second leg 34 have substantially the same width, and as can be seen in fig. 3b, the overall outer contour (before bending) formed by the walls and legs on the same side is substantially rectangular.

The self-destructive syringe capable of drawing a constant amount of liquid in this embodiment is assembled by placing the locking member 3 in one of the recesses 15, and the two pull-out end portions 331 of the locking member 3 are engaged with a pair of first teeth 16 on both side walls of the recess 15 or directly with the center plate 121 on the pull-out side, respectively. As shown in FIG. 4a, the core rod assembly 1 with the locking element is inserted into the barrel 2, and during the process of pushing the core rod towards the inner end of the barrel 2, the locking element can slide along with the core rod assembly 1 inside the barrel 2 due to the tendency of the tips on the first barb 332 and the second barb 311 on the locking element to pull out in the direction. Until the plug body 5 abuts the end wall inside the barrel 2, which can be used or stored. As shown in FIG. 4a, the needle holder 21 may be sleeved with the protecting sheath 4 to protect the puncture needle tube 211, and the protecting sheath 4 may be removed before use.

In use, as shown in FIG. 4b, the plunger assembly 1 is pulled back from the initial position to the second position to draw fluid along the piercing needle 211 to the middle barrel 2. During such retraction, the locking member 3 remains unmoved and the mandrel assembly 1 is moved outwardly of the barrel 2 relative to the outer sheath 22 and locking member 3. Although the present embodiment shows the locking part 3 having four barbs, the locking part 3 may function with a plurality of barbs or with only one barb, and the number and position of the barbs are selected to improve performance. The withdrawal of the first leg and the second leg of the locking member 3 toward the end 331 goes over the respective first teeth 16 in the groove 15 during the retraction of the core assembly 1 until the intermediate disk 121 on the side of the core rod head 13 abuts against the tip of the locking member 3, and the retraction of the core assembly 1 is restricted by the locking member 3 because the locking member 3 cannot be retracted, which may damage the cylinder 2 if an additional axial force is continuously applied to the core assembly 1. Thus, the amount of drug that can be drawn into the barrel 2 is limited by the maximum distance that the plunger assembly 1 can move, i.e., by the initial position of the locking member 3. Because the grooves 15 are uniformly provided with the plurality of first teeth 16, the maximum retraction distance of the core rod assembly 1 can be limited only by changing the engagement between the pull-out end 331 of the locking component 3 and the first teeth 16 of a plurality of groups during assembly, and a designer can realize different quantitative liquid drawing specifications by using components with the same specification according to a cylindrical/conical volume formula by limiting the diameter of the cylinder body 2, the distance between the first teeth 16 and the structural sizes of the core rod assembly 1 and the locking component 3, such as liquid drawing capacities of 0.01ml,0.05ml,0.5ml,1.0ml and 2.0 ml. Therefore, when a precise and quantitative injection is required, excessive liquid drawing for obtaining a precise dose is not needed, and an excessive dose is wasted. Particularly for small-dose injection, through the design, even if the cylinder body 2 with larger size and the core rod are adopted, the small-dose liquid drawing and injection can be simply realized by utilizing the distance between the smaller first teeth 16, the traditional injector with tiny volume and higher production difficulty is not required to be adopted, the operation difficulty is reduced, and the technical requirements on users are greatly reduced. It should be noted that, during production, the pitch of the first teeth 16 may be set to be equally spaced, or not, depending on how many combinations of liquid-drawing capacities the manufacturer wants to achieve on a group of components; further, the syringe may be provided to the end user as a pre-filled syringe, in which case retraction of the core pin assembly 1 is unnecessary or impossible.

Once fluid is drawn into the barrel 2 from a vial or other fluid source, the needle cannula may be removed from the fluid source and used for injection. During injection of a patient, the user or clinician applies an axial force to the plunger rod assembly 1 and locking member 3. At the end of the injection process, the stopper 5 again abuts against the end wall inside the barrel 2. At this time, as shown in FIG. 4c, the locking member 3 preferably remains distally engaged with the intermediate disc 121 on the side of the core rod head 13, and the pull-out end 331 engages the last set of first teeth 16 in the recess 15, i.e., the distance between the last set of first teeth 16 and the intermediate disc 121 on the side of the core rod head 13 is preferably the length of the locking member 3, thereby preventing the core rod assembly 1 from being retracted again, and certainly not being further advanced, so that after a proper dose has been administered, the core rod assembly 1 and the locking member 3 will not substantially move from their positions, and thus, this embodiment cannot be reused. Meanwhile, as can be seen from the above description, although providing more first teeth 16 in the recess 15 does not affect the use of the present embodiment and the intended effect thereof, if the last one or more sets of first teeth 16 are located at a distance from the intermediate disk 121 on the side of the core rod head 13 that is less than the length of the locking member 3, these first teeth 16 do not play any role because the present embodiment cannot be used until they are moved to be engaged with the locking member 3. Thus, the first teeth 16 of the present embodiment are distributed only on the portion between the middle disc 121 and the middle point of the recess 15 in the axial direction in the drawing direction in the recess 15, which also makes the length of the locking member 3 not less than half of the length of the elongated body portion 12, so that the complexity of the stem assembly 1 and the locking member 3 is reduced and the manufacturing cost is reduced.

Furthermore, if one applies excessive rotational or bending force to the plunger assembly 1 in an attempt to pull out the locking element 3 or to reuse the syringe, the presence of the easily breakable connection may cause the plunger to break, thereby forcing the syringe to be unusable.

Those skilled in the art will recognize that the features described in the exemplary embodiments of the present invention are not limited to reduced size syringe assemblies relative to the prior art, and may be used in assemblies for syringes of any desired size.

In an exemplary embodiment of the invention, the locking member 3 is arranged to be inhaled into the barrel 2 in a dose slightly larger than the dose marked on the barrel 2, preferably about 0.01ml larger. In this embodiment, the user or clinician is able to "air purge" with additional volume to remove any air bubbles that may have entered the barrel 2 without reducing the size of the intended effective dose.

In exemplary embodiments of the present invention, the barrel 2 may be constructed of a variety of thermoplastic materials (e.g., polypropylene, polyethylene, and combinations thereof). In an exemplary embodiment of the invention, accurate dose setting may be facilitated by the use of materials that provide clear visibility, as well as the use of fixed dose and bold single scale markings on one or more surfaces of the device. Similarly, thermoplastic materials such as polypropylene, polyethylene, and polystyrene are preferred for the core rod assembly 1 and the plug body 5 of the one-piece plug head type. If the plug body 5 is manufactured as a separate component or by a secondary molding process or the like, various materials such as natural rubber, synthetic rubber, and thermoplastic elastomer are suitable for the plug body 5. The choice of stopper 5 material will depend on compatibility with the drug being used and the barrel 2 material and thickness, as the stopper 5 must form a seal with the inside surface of the barrel 2 in order to deliver the drug through the syringe. Further, the plug body 5, the core pin assembly 1, and/or the barrel 2 may be constructed of a colored or colored material or have an applied color to indicate one or more characteristics of the device, such as a needle gauge or a desired dosage. For example, the device may include an ISO color coded core rod assembly 1 to facilitate quick identification of the gauge.

As previously mentioned, the locking element 3 is preferably made of a harder material than the barrel 2 so as to lock the barbs and effectively engage the barrel 2, yet still have some resiliency while also being low cost and consistent size manufacturing considerations. In view of this, a metal plate is an ideal material for the locking member 3, and stainless steel is preferred. Although the locking member 3 of the preferred embodiment is made from a single sheet, it is within the scope of the invention to include locking members 3 made from other forms and/or comprising multiple members. The locking member 3 may also employ a structure other than the structure shown and described in the present embodiment.

The cartridge 2 used according to the invention may have a wall thickness that varies along its length. The portion intended to contain the medicament may be relatively thin and resilient to ensure a proper seal with the stopper body 5. The remainder of the barrel 2 may be relatively thick and non-resilient, so that the barrel 2 may crack if squeezed by pliers or other means for attempting tampering.

The self-destruction injector capable of quantitatively drawing liquid is automatically locked after injection, so that the injector is prevented from being reused. Thus, it can be seen that embodiments of the present invention can provide a simple, reliable, easily manufactured disposable syringe capable of drawing liquid in a metered amount, which syringe can become non-reusable without any additional action by the user, and which, if additional force is applied, allows the stem assembly to break for further self-destruction.

The above embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and all simple modifications, equivalent changes and modifications made to the above embodiments according to the technical spirit of the present invention still fall within the technical scope of the present invention.

Claims (10)

1. The self-destruction syringe capable of quantitatively drawing liquid is characterized by comprising a cylinder body, a locking component and a mandrel component, wherein the mandrel component comprises a plug body, a user push rod, an extension body part and a groove arranged along the extension body part, a plurality of first teeth are arranged in the groove, and the first teeth form a plurality of shoulders facing the pushing direction of the user push rod;

the core rod assembly can be inserted into the cylinder body;

the locking member is positionable within the recess, the locking member including a body portion;

the body portion includes a first wall and a second wall connected along a longitudinal axis and extending radially;

further comprising first and second legs extending from the first and second walls, respectively, in a pull-out direction of the user putter, wherein at least one of the legs includes a pull-out end portion facing in the pull-out direction of the user putter and engageable with the shoulder portion, the pull-out end portion having a first barb portion extending radially outwardly from an outer edge thereof;

a tip of the barb portion inclined in the pull-out direction for engaging with an inner surface of the barrel to prevent the lock member from sliding in the pull-out direction;

the first teeth are distributed between one end of the groove close to the pull-out direction and the axial middle point of the groove.

2. The self-destructing syringe capable of drawing liquid quantitatively according to claim 1, wherein the first barb portion is provided on an outer edge of each of the first leg and the second leg.

3. The self-destructing syringe capable of drawing liquid quantitatively according to claim 2, wherein the two first barb portions are disposed left-right symmetrically about the longitudinal axis.

4. The self-destruct syringe capable of drawing liquid quantitatively according to claim 1, wherein a second barb portion extends radially outwardly from an outer edge of at least one of said first wall and said second wall, a tip of said second barb portion being inclined toward said pull-out direction for engaging with an inner surface of a barrel to prevent said locking member from sliding in said pull-out direction.

5. The self-destructive syringe capable of drawing liquid quantitatively according to claim 4, wherein the second barb portion is provided on each of outer edges of the first wall and the second wall.

6. The self-destructing syringe capable of drawing liquid quantitatively according to claim 5, wherein the two second barb portions are disposed left-right symmetrically about the longitudinal axis.

7. The self-destructing syringe capable of drawing liquid quantitatively according to claim 1, wherein a gap is left between the first leg and the second leg.

8. The self-destructing liquid scoopable syringe according to claim 1, characterized in that the first and second legs flare outwards from their connection to the first and second walls.

9. The self-destruct syringe capable of drawing liquid quantitatively according to claim 1, wherein the locking member is a sheet member made of a metal plate having elasticity, and a protrusion is provided on the surface thereof.

10. The self-destructive injector capable of drawing liquid quantitatively of claim 1, wherein the user push rod and the extension body part are integrally formed on the stem assembly, and a connection part which is easily broken is provided between the user push rod and the extension body part.

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