A disposable safety syringe

Abstract

The application discloses a disposable safety syringe and relates to the technical field of syringes.The disposable safety syringe comprises a barrel, a push rod arranged to slide along the axial direction of the barrel, a piston arranged on the end of the push rod and matched with the inner wall of the barrel, a nipple arranged on one end of the barrel and used for connecting a needle, the nipple being tapered along the axial direction, an annular recess arranged on the inner wall of the nipple and located in the middle part, a ring-shaped fixing member fixedly connected with the center of the end of the piston, and a blocking member arranged to be compressed in the ring-shaped fixing member, wherein the blocking member is in a radially compressed state in the ring-shaped fixing member in an initial state, and the blocking member is pushed into the annular recess and expanded after being compressed by the piston when the piston abuts against the end of the barrel.The disposable safety syringe is provided with the movable blocking member, the blocking member is pushed by the piston at the end of the injection of the syringe, enters the annular recess and expands, thereby blocking the inside of the nipple, avoiding the secondary use of the barrel, and avoiding the repeated use of the syringe.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of syringes, in particular to a disposable safety syringe. BACKGROUND

[0002] Syringes are the most commonly used medical tools in medical procedures. In order to avoid cross-infection of viruses caused by unhygienic syringes, disposable syringes are mainly used in current medical activities. Therefore, a large number of disposable syringes are discarded every year in countries with relatively high medical standards.

[0003] In order to avoid the discarded disposable syringes being transferred to countries or regions with low medical standards through simple treatment, a locking structure or a destruction structure is usually provided on the disposable syringe, such as an easy-to-break structure provided on the piston push rod. This is the most common and simple way, but there are two problems after use. First, the broken push rod needs to be actively operated by medical staff, and in actual operation, it is directly thrown into a special medical waste bin after use. The second is that the broken push rod does not affect the use of the needle cylinder and the piston, and only the push rod needs to be replaced. Therefore, in the case of interest, the used disposable syringe will still be used. For example, the syringe disclosed in CN113713214B uses two ways of color coating and limiting the movement of the piston rod to prevent secondary use. Although it can play a role, this scheme does not consider the cost and the risk of the color coating when the syringe is normally used. Therefore, it is difficult to be widely used. Therefore, we propose a disposable safety syringe. SUMMARY

[0004] The present application aims to provide a disposable safety syringe to solve the problems raised in the background.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a disposable safety syringe, comprising a barrel, a push rod slidingly arranged in the barrel along the axial direction of the barrel, a piston arranged on the end of the push rod and abutting against the inner wall of the barrel, a nipple arranged on one end of the barrel for connecting a needle, the nipple being tapered along the axial direction, an annular recess arranged in the middle of the inner wall of the nipple, an annular fastener fixedly connected to the center of the end of the piston, the annular fastener being adapted to abut against the inner wall of the nipple, the end of the annular fastener extending to the edge of the annular recess, a plugging member arranged in compression in the annular fastener, the plugging member being in the shape of a shell protruding towards the nipple, and a plurality of expansion joints being arranged at intervals on the radial edge of the plugging member, the plugging member being in a radially compressed state in the annular fastener in the initial state, and the plugging member being pushed into the annular recess after the piston compresses against the end of the barrel.

[0006] Preferably, the annular fixing part is provided with a first extension part at the end face away from the nipple end of the piston, the first extension part is hollow and closed, and the area matched with the annular recess is transitioned outward by a flexible material.

[0007] Preferably, the end part of the push rod is provided with a rigid top rod penetrating the piston and abutting against the blocking part in the initial state.

[0008] Preferably, the annular fixing part is provided with a second extension part at the end face close to the push rod, the second extension part is trumpet-shaped, and the end part is integrally arranged with the piston, and the inner side wall of the second extension part is not fixedly attached to the piston.

[0009] Preferably, the outer edge of the second extension part is further connected with a plurality of protruding parts, and the bottom wall of the protruding part is not fixedly attached to the piston.

[0010] Preferably, the protruding part is an asymmetric part.

[0011] Preferably, the two side edges of the protruding part are arc-shaped, and the distance between the two arc lines decreases radially outward along the empty barrel.

[0012] Preferably, a limiting part is arranged between the end part of the push rod away from the piston and the end part of the empty barrel, and the limiting part limits the excessive movement of the push rod.

[0013] Preferably, the limiting part is a hollow truncated cone formed by the head-to-tail coupling of the two ends of the fan ring.

[0014] Compared with the prior art, the beneficial effects of the present application are:

[0015] By arranging the movable blocking part, the blocking part is pushed by the piston at the end of the injection of the syringe, so as to enter the annular recess and expand, thereby blocking the inside of the nipple, avoiding the reuse of the empty barrel, and avoiding the reuse of the syringe;

[0016] By arranging the first extension part extending into the nipple and being closed, the residual liquid in the nipple can be injected when the piston pushes the liquid injection, thereby reducing the residual amount of the liquid.

[0017] The first extension part of the present application also limits the piston, so that the piston cannot be reused, which makes the most of the syringe cannot be reused, thereby effectively avoiding the reuse and avoiding the health problems such as cross infection;

[0018] The second extension part and the protruding part arranged in the present application will cause the surface of the piston to be damaged when forcibly pulling out the piston, thereby losing the practical value and avoiding the secondary processing and use.

[0019] The setting of the present application is relatively simple, and the relative production cost increment is very small, and it is beneficial to popularize and use in a large range. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a whole sectional structure schematic diagram of a present disposable syringe;

[0021] Figure 2 It is a whole sectional structure schematic diagram of the present application;

[0022] Figure 3 It is Figure 2 It is an enlarged schematic diagram of the structure of area A;

[0023] Figure 4 It is a half sectional structure schematic diagram of the blocking member in two states;

[0024] Figure 5 It is a top view structure schematic diagram of the blocking member in two states;

[0025] Figure 6 It is a half sectional structure schematic diagram of the annular fastener and the first extension and the second extension;

[0026] Figure 7 It is a structure schematic diagram between the second extension and the protruding part and the piston;

[0027] Figure 8 It is a schematic diagram of the second extension and the piston surface in a pulling state;

[0028] Figure 9 It is a schematic diagram of one implementation structure of the limiting part.

[0029] In the figure: 1 - empty barrel; 2 - push rod; 3 - piston; 4 - nipple; 5 - annular recess; 6 - annular fastener; 7 - blocking member; 8 - expansion joint; 9 - ejector rod; 10 - limiting part; 61 - first extension; 62 - second extension; 621 - protruding part. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0031] Reference is made to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6The application provides a technical scheme: a disposable safety syringe, comprising a hollow cylinder 1, the hollow cylinder 1 is a straight cylinder structure with one end open, the open end is connected with a nipple 4 at the other end, the nipple 4 is a hollow cone shape, used for connecting a needle, the open end of the hollow cylinder 1 is also integrally provided with a finger hook;

[0032] One end of the push rod 2 is detachably provided with a piston 3, generally a columnar plug is arranged at the end of the push rod 2, the columnar plug is arranged at intervals along the axial direction, and a groove is adapted to be arranged at the bottom of the piston 3, the end of the push rod 2 away from the piston 3 is integrally connected with a push handle, the push handle is used for pushing the push rod 2, and the other two fingers are placed on the finger hook to realize injection, the above are conventional parts of the existing disposable syringe;

[0033] In the present application, a ring-shaped recess 5 is arranged in the inner wall of the nipple 4, the ring-shaped recess 5 is located at the middle position, that is, the ring-shaped recess 5 does not overlap with the two end edge lines of the inner wall of the nipple 4 along the axial direction of the hollow cylinder 1, and further, the ring-shaped recess 5 is radially outward from the axis of the hollow cylinder 1, and the edge lines of the cross section of the ring-shaped recess 5 tend to be opposite at the two ends in the axial direction of the hollow cylinder 1, that is, the ring-shaped recess 5 does not have the condition of being smaller inside and larger outside in the radial direction, which increases the production difficulty, the ring-shaped fastener 6 is solid, that is, non-flexible, the outer wall of the ring-shaped fastener 6 is adapted to the inner wall of the nipple 4, and the main function of the ring-shaped fastener 6 is to stably block the blocking piece 7 in the initial state;

[0034] The blocking piece 7 is a disc-shaped shell protruding to one side, and a radial expansion joint 8 is arranged at the edge, Figure 4 and Figure 5 as shown, the initial state is a compressed state, that is, Figure 4 the one with a larger arc below in Figure 5 corresponding to the right side in Figure 4 , in the compressed state, the outer edge of the blocking piece 7 is limited by the inner wall of the ring-shaped fastener 6 and moves together with the ring-shaped fastener 6, and after unfolding, the blocking piece 7 is like Figure 5 the one with a smaller arc above and corresponding to the left side in , the unfolded blocking piece 7 enters the ring-shaped recess 5, because the inner wall of the nipple 4 is conical, it cannot be pushed out in the injection direction, and it cannot be compressed in the opposite direction because the bending direction of the blocking piece 7 is opposite, so it cannot be separated;

[0035] Specifically, in use, in the initial state, the piston 3 is attached to the end inner wall of the empty barrel 1, in this state, the blocking piece 7 is compressed in the annular fastener 6, and is in a critical state, only needs to apply external force in the axial direction to enter the annular recess 5 and expand, this initial state is the factory setting state, when the medical staff uses it, first insert the needle, then insert the needle into the medicine bottle or other medicine carrier, pull the push rod 2 to generate negative pressure to suck medicine, after the medicine is sucked, injection is carried out, push the push rod 2, when the end face of the piston 3 contacts the inner bottom wall of the empty barrel 1, that is, at this time, it is in the state of injection completion, because the push rod 2 is directly pushed during extrusion and has no limit, therefore, when the piston 3 contacts the inner bottom wall of the empty barrel 1, the piston 3 will be compressed, and the part of the piston 3 corresponding to the range of the annular fastener 6 is not limited, which will advance a little relatively, so as to push the blocking piece 7 out of the annular fastener 6, the annular fastener 6 itself is limited by the taper of the inner side wall of the nipple 4 and cannot move, after the blocking piece 7 enters the annular recess 5 from the annular fastener 6, because the side is not limited, it will automatically expand, and then block, that is, the empty barrel 1 cannot be used again;

[0036] Because of the structure of the blocking piece 7, it is difficult to be pushed out from both ends of the nipple 4, and if it is forcibly destroyed, the empty barrel 1 will also be easily damaged, and because the blocking piece 7 is in a movable state in the annular recess 5, it is also difficult to handle the blocking piece 7 with a rotating drill bit, so that it is difficult to use it again after being used once, even if it can be used after being handled, it will also lose the value of handling because the handling cost is too large and no longer profitable.

[0037] Referring to Figure 3 and Figure 6 , the first extension 61 is in the form of a reverse cup structure as a whole, the outer side wall is matched with the inner wall of the nipple 4, the first extension 61 is divided into two parts, one part is in a flexible structure and protrudes outward in the radial direction, so as to be matched with the annular recess 5 and be compressed before entering the annular recess 5, the other part is completely attached to the inner wall of the nipple 4, this part can adopt a rubber structure like the piston 3, or a solid plastic structure, its sealing state not only isolates the blocking piece 7 from the internal environment of the empty barrel 1, so as to avoid the influence of the medicine on the medicine, but also can realize the function of cleaning the remaining medicine in the nipple 4, because in the traditional disposable injection, the medicine in the nipple 4 cannot be used to inject into the patient's body, but the first extension 61 can realize this function;

[0038] Referring to Figure 3In this embodiment, the top rod 9 is coaxially arranged at the end of the push rod 2, and one end of the top rod 9 is in contact with the blocking member 7, and the side wall of the top rod 9 is wrapped by the piston 3 and is slidable. The top rod 9 is arranged to facilitate better pushing of the blocking member 7. In the state without the top rod 9, the relative movement amount of the piston 3 in the internal range of the annular fastener 6 is small, and it is possible that the blocking member 7 cannot be completely pushed out. Therefore, the top rod 9 is arranged to completely avoid this situation and better push the blocking member 7.

[0039] In the first extension 61, the end of the piston 3 is directly arranged to avoid friction, one end of the top rod 9 is connected to the push rod 2, and the other end is in contact with the blocking member 7. After the first extension 61 is arranged, the blocking member 7 is limited and cannot be pulled back to the original position for reuse, otherwise the first extension 61 or the piston 3 will be damaged.

[0040] Referring to Figure 3 , Figure 6 and Figure 8 , the second extension 62 is connected to the lower end of the annular fastener 6. The second extension 62 is preferably made of the same material as the piston 3 and is integrally arranged, that is, the second extension 62 can be regarded as a part of the top surface of the piston 3. However, one end of the second extension 62 is in a movable state. When the push rod 2 is pulled or the piston 3 is pulled by other tools during the secondary processing of the syringe, the second extension 62 will be pulled, and the piston 3 will move downward, as shown in Figure 8 . The pulling of the second extension 62 can tear the integrity of the upper surface of the piston 3, and because of the uncertainty of the breakage, it can affect the overall sealing performance, thereby indirectly losing the value of the piston 3 for secondary use.

[0041] Referring to Figure 7 and Figure 8 , compared with the second extension 62 with a complete edge, it can also be torn when it is pulled, without damaging the surface of the piston 3. Therefore, as shown in Figure 7 , the protruding part 621 is arranged in a relatively irregular state and extends to more areas of the surface of the piston 3. Similarly, in the pulling state as shown in Figure 8 , the damage caused by the protruding part 621 to the surface of the piston 3 is greater than that caused by the second extension 62;

[0042] Further, the asymmetric protruding part 621 is easy to concentrate the stress when it is pulled, thereby better tearing the surface of the piston 3;

[0043] Further, the two side edges of the protrusion 621 are arc-shaped, and the distance between the two arcs decreases radially outward along the empty cylinder 1, that is, the two edges first present a same-direction spiral shape, and the surface of the piston 3 decreases in size radially outward. Such a design makes the protrusion 621, when being pulled, can generate a strip-shaped crack on the surface of the piston 3, and because of the spiral shape, it is more conducive to tearing.

[0044] In order to avoid the piston 3 or the ejector rod 9 being pushed out of the sealing element 7 in advance due to collision during the production and transportation of the package, the limiting part 10 is arranged to limit the axial advancement of the push rod 2;

[0045] As one of the embodiments, the limiting part 10 is a ring-shaped conical structure with a fan ring structure in the unfolded state, and the end face can be C-shaped. The limiting part 10 is clamped on the push rod 2 through its toughness to limit the axial movement of the push rod 2, or the limiting part 10 can be connected head to tail, and the connected part is buckled or glued, and an easy-to-tear opening is arranged at one end on the outside.

[0046] It should be noted that the relational terms herein such as first and second, and the like are used only to differentiate one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In addition, the terms "comprise", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment.

[0047] Although the embodiments of the present application have been shown and described, it is understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A disposable safety syringe, comprising an empty cylinder (1), a plunger (2) slidably disposed within the empty cylinder (1) along its axial direction, a piston (3) fitted to the inner wall of the empty cylinder (1) at the end of the plunger (2), and a nipple (4) for connecting a needle at one end of the empty cylinder (1), the nipple (4) being tapered along its axial direction, characterized in that: The inner wall of the nipple (4) is provided with an annular recess (5) in the middle. An annular fastener (6) is fixedly connected to the center of the end of the piston (3). The annular fastener (6) is adapted to fit the inner wall of the nipple (4). The end of the annular fastener (6) extends to the edge of the annular recess (5). A sealing member (7) is compressed inside the annular fastener (6). The sealing member (7) is a shell-shaped body protruding towards the end of the nipple (4). Several expansion joints (8) are opened at intervals at the radial edge of the sealing member (7). In the initial state, the sealing member (7) is in a radially compressed state inside the annular fastener (6). After the piston (3) abuts against the end of the empty cylinder (1) and is compressed, the sealing member (7) is pushed into the annular recess (5). The annular fastener (6) has a first extension (61) at the end facing the nipple (4) away from the piston (3). The first extension (61) is hollow and closed, and the area adapted to the annular recess (5) is made of flexible material for outward transition. The push rod (2) has a rigid push rod (9) at the center of its end, which penetrates the piston (3) and abuts against the sealing member (7) in the initial state. The annular fastener (6) has a second extension (62) on the end face near the push rod (2). The second extension (62) is horn-shaped and its end is integrally formed with the piston (3). The inner sidewall of the second extension (62) is not attached to or fixed to the piston (3).

2. A disposable safety syringe according to claim 1, characterized in that: The outer edge of the second extension (62) is also connected to several protrusions (621), the bottom wall of which is not attached to the piston (3).

3. A disposable safety syringe according to claim 2, characterized in that: The protrusion (621) is an asymmetrical component.

4. A disposable safety syringe according to claim 3, characterized in that: The two sides of the protrusion (621) are arc-shaped, and the distance between the two arcs decreases radially outward along the empty cylinder (1).

5. A disposable safety syringe according to claim 1, characterized in that: A limiting part (10) is provided between the end of the push rod (2) away from the piston (3) and the end of the empty cylinder (1), and the limiting part (10) restricts the excessive movement of the push rod (2).

6. A disposable safety syringe according to claim 5, characterized in that: The limiting part (10) is a hollow frustum-shaped structure formed by the coupling of the two ends of the fan ring.

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