CN220125255U - Protective device for syringe and disposable safety syringe thereof - Google Patents

Abstract

The utility model relates to a protective device for a syringe and a disposable safety syringe thereof, wherein the protective device for the syringe comprises a shell, a protective inner sleeve, an excitation ring and a spring; the upper side of the inner part of the shell is respectively provided with a guide bulge and a limit bulge; the lower part of the shell is provided with a locking spring piece; the upper part of the excitation sleeve is a guide cylinder, a guide groove is formed in the wall surface of the guide cylinder, the lower part of the excitation sleeve is an excitation cylinder, an excitation groove penetrating through the wall surface is formed in the excitation cylinder, and an excitation inclined surface which is obliquely arranged upwards is arranged in the excitation groove; the upper part of the protective inner sleeve is provided with an outwards-protruding guide post, the middle upper part of the protective inner sleeve is provided with an outwards-protruding limiting ring, and the limiting ring is provided with an opening. The disposable safety syringe, the disposable prefilled syringe is installed in the protective device for the syringe. The utility model has simple structure, easy manufacture and assembly, no exposure of the excitation part, consistent force application direction of the excitation action and the injection action, convenient operation and better safety and reliability.

Description

Protective device for syringe and disposable safety syringe thereof

Technical Field

The utility model relates to a protective device for a syringe, which provides a needle head protective function for a disposable prefilled syringe, and a disposable safety syringe formed by adopting the protective device, and belongs to the field of medical injection instruments.

Background

The inventor previously applied for a safety syringe with a Chinese patent publication No. CN111888580A and a needle protection device for the safety syringe with a Chinese patent publication No. CN111888581A, designed a special needle protection device, when the disposable syringe is used, the syringe (containing medicament) is arranged in the protection device, then after the medicine pushing injection process is finished, the protection device is excited, a protective sleeve is ejected, the needle of the syringe is protected, and the needle of the syringe is shielded, so that accidents such as hurting people and the like caused by the needle of the syringe after the use are prevented.

However, a safety syringe of chinese patent publication No. CN111888580a needs to use a special syringe piston rod, and is activated by a release activation piece on the piston rod, which may require the pharmaceutical manufacturing enterprise to replace the piston rod of the syringe, resulting in some inconvenience. On the basis, the Chinese patent publication No. CN218187476U prevents the stab protection device, reduces the requirement on the piston rod, but requires additional operation for excitation; the excitation action is separated from the injection action, and the excitation device can be misoperated before injection to directly excite, so that the injection of the medicament can not be performed.

The needle head protection device for the safety syringe with the Chinese patent publication No. CN111888581A is provided with a guide groove with a relatively complex structure, the production and manufacturing difficulties are relatively high, and the assembly process is relatively complex.

Therefore, there is a need for further improvements in needle protection devices for safety syringes that simplify handling and reduce the requirements on the syringe itself, as well as ease of manufacture and assembly.

Disclosure of Invention

The utility model aims to provide a protective device for an injector and a disposable safety injector formed by sampling the protective device for the injector, and the integral structure of the protective device is improved, so that the requirement on the injector is simplified, and the protective device is matched with a conventional disposable prefilled injector; the parts of the protection device have simple structure and are easy to manufacture and assemble; in addition, the protective device is convenient to assemble with the injector in the use process, and the excitation operation process is also convenient, so that false excitation is avoided; the whole protection device is externally provided with no excitation mechanism, and can not be triggered by mistake from the outside, so that the problem of false excitation is further effectively avoided.

In order to achieve the above object, according to a first aspect of the present utility model, there is provided a protector for a syringe, comprising a housing, a protective inner sleeve, an energizing ring, and a spring;

the lower part of the main body is a shell of a thin-wall cylinder, a cylindrical inner sleeve accommodating cavity is formed in the shell, and the inner sleeve accommodating cavity is vertically communicated; handle fins extending outwards from two sides are arranged above the shell; the top of the shell is provided with a mounting table which is of a hollow structure, and the mounting table forms a hollow movable space above the handle wing pieces;

the upper side of the inner part of the shell is respectively provided with a guide bulge and a limit bulge; wherein, the guide bulge is arranged close to the mounting table and is positioned at the top of the inner side of the shell; the limiting bulge is positioned at the middle upper part of the shell, and a space is arranged between the limiting bulge and the guide bulge;

the lower part of the shell is provided with a locking spring piece, and a limit boss is arranged below the locking spring piece; a locking cavity is formed between the locking spring plate and the limiting boss;

the locking spring piece is a cantilever spring piece arranged along the outer wall of the shell, three sides of the locking spring piece are hollowed out to form a yielding groove, the fixed end of the locking spring piece is arranged along the radial direction of the shell, the fixed end of the locking spring piece is positioned above, and the lower part of the locking spring piece is a movable end; the lower part of the locking spring plate protrudes inwards to form a locking boss, and the upper part of the locking boss is provided with a guide inclined surface which is arranged downwards and inwards;

the limiting boss is a horizontally arranged platform and protrudes towards the inner wall of the shell;

the shell is internally provided with an excitation assembly consisting of a protective inner sleeve, an excitation sleeve and a spring;

the excitation sleeve is a thin-wall cylinder, and a cylindrical spring accommodating cavity is arranged on the inner side of the excitation sleeve; the upper part of the excitation sleeve is a guide cylinder, the top of the guide cylinder extends inwards to form a spring seat, and the top of the spring accommodating cavity is partially sealed to form top limit of the spring; the wall surface of the guide cylinder is provided with a guide groove, the guide groove is arranged along the axial direction of the excitation sleeve and penetrates through the axial direction of the guide cylinder, the guide groove is internally provided with a guide bulge of the shell, and the guide groove and the guide bulge can move relatively; the lower part of the excitation sleeve is an excitation cylinder, an excitation groove penetrating through the wall surface is arranged on the excitation cylinder, and an excitation inclined plane which is arranged obliquely upwards is arranged in the excitation groove;

the protective inner sleeve is a thin-wall cylinder, and a syringe accommodating cavity which penetrates up and down is arranged in a cylinder shell of the protective inner sleeve; the upper part of the cylinder shell is provided with a guide post which protrudes outwards; the upper middle part of the cylinder shell is provided with a limiting ring which protrudes outwards, and the limiting ring is provided with an opening;

the width of the limiting bulge is smaller than the width of the opening and smaller than the width of the locking spring plate;

the top of the cylinder shell is a supporting surface of the spring;

the spring is a compression spring and is always in a compression state;

the protective inner sleeve is positioned in the inner sleeve accommodating cavity of the shell; before excitation, a limiting ring of the protective inner sleeve is propped against the upper part of the limiting bulge, and the opening is far away from the limiting bulge; before excitation, the guide post is clamped into the excitation groove and is propped against the excitation inclined plane;

when the device is excited, the opening of the limiting ring is consistent with the position of the limiting bulge;

after excitation, the limiting ring is positioned in the locking cavity, and the lower part of the protective inner sleeve protrudes out of the outer shell;

the spring is positioned between the supporting surface of the protective inner sleeve and the spring seat of the excitation sleeve.

As a further improvement of the utility model, the inner side of the shell is provided with 2 guide bulges and limiting bulges;

the guide protrusions and the limit protrusions are symmetrically arranged on the inner side wall surface of the shell;

the guide protrusions and the limit protrusions are narrow protrusions;

the width of the guide protrusion is smaller than the width of the opening;

the opening on the limiting ring of the protective inner sleeve is provided with 2 parts, the two parts are symmetrically arranged on the limiting ring, and the position of the opening corresponds to the limiting bulge.

As a further improvement of the utility model, the guide projection and the limit projection are positioned on the same direction of the inner wall of the housing.

As a further improvement of the utility model, the locking spring plate is provided with 2 parts which are symmetrically arranged on the shell.

As a further improvement of the utility model, the excitation groove and the excitation inclined plane on the excitation sleeve are provided with 2 parts which are symmetrically arranged in the wall surface of the excitation cylinder;

the number of the guide posts is 2, and the guide posts are symmetrically arranged on the outer wall of the cylinder shell;

the setting position of the guide post corresponds to the excitation inclined plane.

As a further improvement of the utility model, the outer diameter of the limiting ring of the protective inner sleeve is smaller than the inner diameter of the inner sleeve accommodating cavity of the shell, and the protective inner sleeve and the shell can move relatively freely.

As a further development of the utility model, the thickness of the stop collar is smaller than the height of the locking cavity.

The protective device for the injector of the utility model comprises the following components:

(1) Firstly taking a shell;

(2) Then taking the protective inner sleeve, plugging the lower part of the protective inner sleeve from the upper part of the shell, penetrating through the mounting table and completely entering the inner sleeve accommodating cavity; in the process, an opening on the limiting ring firstly passes through the guide bulge to enable the limiting ring to be positioned between the guide bulge and the limiting bulge, then the protective inner sleeve is rotated for a certain angle to enable the opening to leave the position of the limiting bulge, finally the limiting ring is enabled to fall on the limiting bulge, and the protective inner sleeve is temporarily fixed in an inner sleeve accommodating cavity of the shell;

(3) Taking a spring, plugging the bottom of the spring from the upper part of the shell, penetrating through the mounting table, abutting the bottom of the spring on a supporting surface at the top of a cylinder shell of the protective inner sleeve, and limiting the bottom of the spring;

(4) The method comprises the steps that an excitation sleeve is taken, the lower part of the excitation sleeve is compared with the top of a spring, the upper part of the spring is accommodated in a spring accommodating cavity, and the top of the spring is propped against the lower surface of a spring seat, so that the top of the spring is limited;

compressing the excitation sleeve downwards to enable the excitation sleeve to enter the mounting table part of the shell, and aligning the guide groove with the guide protrusion; the excitation sleeve is continuously compressed downwards, the spring is further compressed, the guide protrusion is clamped into the guide groove, the guide post is accommodated in the excitation groove, and the guide post abuts against the excitation inclined plane.

Thus, the assembly of the protective device for the injector is completed; the actuating sleeve is then held against the spring and is not held in place, and once the force applied to the actuating sleeve is released, the spring is released, ejecting the actuating sleeve from the housing.

To achieve locking of the trigger sleeve, a further need exists to incorporate a disposable pre-filled syringe, a second aspect of the present utility model, providing a disposable safety syringe comprising a guard for a syringe as described above, having a disposable pre-filled syringe mounted therein;

the flange of the injector is arranged in the mounting table and is positioned above the excitation sleeve; the needle cylinder is positioned in the injector accommodating cavity of the protective inner sleeve;

before the disposable safety syringe is used, the needle of the syringe passes through the protective device for the syringe and is positioned at the outer side of the protective inner sleeve;

after the disposable safety syringe is used, the lower part of the protective inner sleeve passes over the needle of the syringe after the protective device for the syringe is completely excited, and the needle of the syringe is wrapped in the syringe accommodating cavity.

As a further improvement of the utility model, the length of the push rod is longer than the length of the needle cylinder;

after the injection of the medicament in the needle cylinder is finished, the push head of the push rod is positioned above the mounting table or positioned at the upper part of the mounting table.

As a further improvement of the utility model, the inner diameter of the injector accommodating cavity of the protective inner sleeve is larger than the outer diameter of the syringe of the injector, and the protective inner sleeve and the syringe can move relatively freely.

The assembly process of the disposable safety syringe comprises the following steps:

taking a disposable prefilled syringe, aligning the needle of the syringe with the protective device for the syringe, inserting the needle into the excitation sleeve, penetrating through the spring, and entering into the syringe accommodating cavity of the protective inner sleeve, wherein the needle cylinder of the syringe also enters into the syringe accommodating cavity along with the needle part penetrates through the syringe accommodating cavity and reaches the outside of the protective inner sleeve; the flange of the injector is installed in the installation table, the bottom of the flange is contacted with the top of the excitation sleeve, the flange completely enters the movable space, the flange is limited by the solid part of the installation table because the section size of the flange is larger than the inner side size of the installation table, the flange is loosened at the moment, the flange is also left in the installation table to form fixation, the excitation sleeve is limited by the flange, temporary fixation is obtained, and the spring is compressed.

When the disposable safety syringe is used, similar to a common syringe, the shell is grasped, the needle is pricked into a patient, and the downward acting force grasping the shell in the process is completely applied to the needle through the mounting table, the flange and the syringe; then the finger buckles the lower part of the handle wing, the other 1 finger is propped against the push head at the top of the push rod to apply force, and the push rod pushes the piston at the bottom to move in the syringe, so that the medicament is injected into a patient through the needle head.

When the medicine pushing injection is finished, the piston reaches the end of the needle cylinder, and the pushing head is positioned outside the mounting table, so that the subsequent operation is convenient; after the injection is finished, the injector is driven to integrally move upwards, and the needle head is pulled out of the patient.

After the needle cylinder is pulled out, the force is still applied to the push head, so that the push rod drives the piston to continuously move downwards, and then the piston pushes the needle cylinder to move downwards along with the relative shell, and then the flange also moves downwards along with the needle cylinder; the flange moves downwards along with the excitation sleeve, the spring is further compressed, the excitation sleeve moves vertically downwards relative to the shell under the limit of the guide protrusion and the guide groove 34, the excitation inclined plane presses the guide pillar of the protection inner sleeve downwards in the process, so that the guide pillar slides along the excitation inclined plane, and the guide pillar moves obliquely relative to each other along the excitation inclined plane due to the fact that the limit ring of the protection inner sleeve abuts against the limit protrusion in the process, and the excitation sleeve moves downwards relative to the shell and the protection inner sleeve rotates relative to the shell.

The force is applied to the push head to enable the push head to move one end for a distance until the flange moves downwards to be close to the handle wing, the limiting ring of the protective inner sleeve reaches the limiting bulge along with rotating to the opening part, at the moment, the limiting ring of the protective inner sleeve loses the limiting of the limiting bulge, the spring is instantly released, the protective inner sleeve is pushed downwards relative to the shell, and the limiting ring passes through the limiting bulge and reaches the lower part of the limiting bulge.

The spring continues to release, and the protective inner sleeve continues to be pushed out downwards relative to the outer shell.

Finally, the limiting ring passes over the locking elastic sheet under the action of the spring and enters the locking cavity, and finally abuts against the limiting boss, the locking elastic sheet automatically resets, the limiting ring of the protective inner sleeve is clamped in the locking cavity, and the protective inner sleeve is fixed; the bottom of the protective inner sleeve extends out fully relative to the outer shell, so that the needle head of the syringe is covered fully, and the needle head of the used syringe is protected fully.

And the force on the pushing head is removed, the spring also pushes the excitation sleeve to reset upwards, the excitation sleeve drives the flange to move upwards in the movable space, and finally the top of the flange is propped against the lower part of the top entity of the mounting table, so that the limit is obtained. The flange carries the injector to reset upwards, so that the needle head is properly lifted, and the safety protection distance is further increased.

The utility model mainly improves the protective device for the syringe, and further combines with the disposable prefilled syringe to form a disposable safety syringe, which can be conveniently matched with the conventional disposable prefilled syringe; the mounting table is reasonably designed, so that the flange of the existing injector can be conveniently mounted and fixed, and the assembly is also convenient; the final excitation of the protective device is required to rely on the full use of the medicament in the prefilled syringe, and the piston is utilized to push the needle cylinder and drive the flange to push the excitation sleeve for excitation, so that the false triggering of the protective device is avoided; the force application process of the excitation process is completely consistent with the medicine pushing injection process, and no additional operation steps are needed, so that the method is simple and convenient; particularly, the upper part of the outer side of the shell of the protecting device for the syringe is free of an exposed part, the exciting assembly cannot be excited by external force, and only after the medicament in the prefilled syringe is completely injected, the internal excitation can be realized, so that the safety and the reliability are better.

The protective device for the injector has a simple structure and is easy to process and manufacture; the final safety syringe has the advantages of convenient assembly, simple and convenient operation and good protection effect.

Drawings

FIG. 1 is a view showing the overall structure of a protector for a syringe (before excitation) according to the present utility model;

FIG. 2 is an overall structural outline view of the disposable safety syringe (before use) of the present utility model;

FIG. 3 is an exploded view of the components of a guard for a syringe according to the present utility model;

figure 4 is an overall structural outline view of the housing of the protective device;

fig. 5 is a perspective view showing an internal structure of a housing of the guard;

FIG. 6 is a cross-sectional view of the internal structure of the housing of the guard;

FIG. 7 is a schematic view of the internal structure of the housing of the guard;

FIG. 8 is an overall structural outline view of the firing assembly of the guard;

FIG. 9 is an overall structural outline of the excitation sheath of the protective device of FIG. 1;

FIG. 10 is an overall structural outline of the excitation sheath of the protective device of FIG. 2;

FIG. 11 is an overall structural outline view of the inner protective sleeve of the protective device;

FIG. 12 is a schematic view in internal cutaway of FIG. 2;

FIG. 13 is an overall structural outline view of the disposable safety syringe when the injection of the medicament is completed;

FIG. 14 is an internal cutaway schematic view of FIG. 13;

FIG. 15 is an internal cross-sectional view of the activation process of the guard of the single use safety syringe;

FIG. 16 is an overall structural outline view of the excitation assembly in the state of FIG. 15;

FIG. 17 is an internal cross-sectional view of the shield apparatus of the single use safety syringe at the moment of activation;

FIG. 18 is a schematic view in internal cutaway in the state of FIG. 17;

FIG. 19 is an overall structural outline view of the excitation assembly of FIG. 17;

FIG. 20 is an overall structural outline view of the disposable syringe-containing activation assembly in the state of FIG. 17;

FIG. 21 is a schematic view in perspective with internal cutaway of the shielding device in an initial stage of actuation;

FIG. 22 is a general structural outline view of the disposable safety syringe at an intermediate stage of activation of the guard;

fig. 23 is an internal cross-sectional view in the state of fig. 22;

FIG. 24 is a view showing the overall structure of the disposable safety syringe after the activation of the guard is completed;

FIG. 25 is a schematic view in internal cutaway in the state of FIG. 24;

fig. 26 is an internal cross-sectional view in the state of fig. 24.

Detailed Description

The following describes the embodiments of the present utility model in further detail with reference to the drawings.

Fig. 1 is a view showing the overall structure of a protector for a syringe (before activation) according to the present utility model, in which a disposable prefilled syringe is assembled, i.e., a view showing the overall structure of a disposable safety syringe (before use) according to the present utility model shown in fig. 2.

The protective device for the injector of the utility model further comprises a shell 1, a protective inner sleeve 2, an excitation sleeve 3 and a spring 4 as shown in figure 3.

The housing 1 is shown in fig. 4, and the interior thereof is shown in fig. 5, 6 and 7; the lower part of the main body of the shell 1 is a shell 11 of a thin-wall cylinder, a cylindrical inner sleeve accommodating cavity 12 is formed in the shell 11, and the inner sleeve accommodating cavity 12 is vertically communicated; handle fins 13 extending to the outside of both sides are arranged above the shell 11; the top of the shell 1 is provided with an installation table 14 which is of a hollow structure, and a hollow movable space 141 is formed above the handle wing pieces 13.

A guide protrusion 15 and a limit protrusion 16 are respectively arranged on the upper side of the interior of the shell 11; wherein the guide projection 15 is provided close to the mounting table 14, i.e., at the inner top of the housing 11; and the limit projection 16 is positioned at the middle upper part of the shell 11 and is spaced from the guide projection 15.

Further, 2 guide protrusions 15 and limiting protrusions 16 are preferably arranged on the inner side of the shell 11, and the guide protrusions 15 and the limiting protrusions 16 are symmetrically arranged on the inner side wall surface of the shell 11; the guide protrusion 15 and the limit protrusion 16 are narrow protrusions.

In this embodiment, for convenience of processing, the guide protrusion 15 and the limit protrusion 16 are in the same orientation; in actual production, the guide protrusion 15 and the limit protrusion 16 can be in different orientations.

The lower part of the shell 11 is provided with a locking spring piece 17, a limit boss 18 is arranged below the locking spring piece 17, the locking spring piece 17 and the limit boss 18 extend and protrude towards the inner side of the shell 11, and a locking cavity 19 is formed between the locking spring piece 17 and the limit boss 18.

Further, the locking spring 17 is a cantilever spring arranged along the outer wall of the shell 11, preferably 2 parts are arranged, and symmetrically arranged on the shell 11; three sides of the locking spring piece 17 are hollowed out to form a yielding groove 171, the fixed end of the locking spring piece 17 is arranged along the radial direction of the shell 11, the fixed end of the locking spring piece 17 is positioned above, and the lower part of the locking spring piece 17 is a movable end; the lower part of the locking spring 17 protrudes inwards to form a locking boss, and the upper part of the locking boss is provided with a guiding inclined surface 172 which is arranged downwards and inwards.

And the limit boss 18 is a horizontally disposed platform.

The shell 1 is internally provided with an excitation component, as shown in fig. 8, which is formed by combining a protective inner sleeve 2, an excitation sleeve 3 and a spring 4.

The specific structure of the excitation sleeve 3 is shown in fig. 9 and 10; a thin-walled cylinder barrel, the inner side of which is provided with a cylindrical spring accommodating cavity 32; the upper part of the excitation sleeve 3 is provided with a guide cylinder 31, the top of the guide cylinder 31 extends inwards to form a spring seat 33, the top of the spring accommodating cavity 32 is partially closed, and the top of the spring accommodating cavity is used for limiting the top of the spring 4; the guide tube 31 has a relatively thick wall thickness, and is provided with a guide groove 34, and the guide groove 34 is arranged along the axial direction of the excitation sleeve 3 and penetrates through the axial direction of the guide tube 31. The lower part of the excitation sleeve 3 (namely, the lower part of the guide cylinder 31) is an excitation cylinder 35, an excitation groove 36 penetrating through the wall surface is arranged on the excitation cylinder 35, and an excitation inclined surface 37 arranged obliquely upwards is arranged in the excitation groove 36; preferably, the excitation grooves 36 and the excitation inclined planes 37 are symmetrically arranged in the wall surface of the excitation cylinder 35 at 2 positions.

The protective inner sleeve 2 is a thin-wall cylinder, the specific structure of which is shown in fig. 11, and a syringe accommodating cavity 22 which is penetrated up and down is arranged in a cylinder shell 21 of the inner sleeve; the upper part of the cylinder shell 21 is provided with guide posts 23 protruding outwards, and the number of the guide posts 23 is preferably 2 and symmetrically arranged on the outer wall of the cylinder shell 21. The guide posts 23 are clamped into the excitation grooves 36 and abut against the excitation inclined surfaces 37, so that the number and positions of the guide posts 23 correspond to the excitation grooves 36 and the excitation inclined surfaces 37. The middle upper part of the cylinder shell 21 (namely, the lower part of the guide post 23) is provided with a limiting ring 24 which protrudes outwards, the limiting ring 24 is provided with openings 25, and the number and the positions of the openings 25 correspond to those of the limiting protrusions 16.

Further, the width of the limiting protrusion 16 is narrower than the width of the locking spring 17, the width of the corresponding opening 25 is wider than the width of the limiting protrusion 16, and the width of the opening 25 is narrower than the width of the locking spring 17. (width of the limit projection 16) < (width of the opening 25) < (width of the locking spring piece 17).

The top of the cartridge 21 is the bearing surface 211 of the spring 4 (see fig. 12 for details).

The spring 4 is a compression spring, and is always in a compressed state in the utility model, and provides elastic force outwards on the upper side and the lower side.

The protective device for the injector of the utility model comprises the following components:

(1) Firstly taking a shell 1;

(2) Then taking the protective inner sleeve 2, plugging the lower part of the protective inner sleeve 2 from the upper part of the shell 1, penetrating the mounting table 14 and completely entering the inner sleeve accommodating cavity 12; in the process, the opening 25 firstly passes through the guide bulge 15 to enable the limiting ring 24 to be positioned between the guide bulge 15 and the limiting bulge 16, then the protective inner sleeve 2 is rotated for a certain angle to enable the opening 25 to enable the limiting bulge 16 to be opened, and finally the limiting ring 24 is enabled to fall on the limiting bulge 16 to enable the protective inner sleeve 2 to be temporarily fixed in the inner sleeve accommodating cavity 12 of the shell 1;

(3) Taking the spring 4, plugging the bottom of the spring 4 from the upper part of the shell 1, penetrating through the mounting table 14, and abutting the bottom of the spring 4 on a supporting surface 211 at the top of a cylinder shell 21 of the protective inner sleeve 2 to limit the bottom of the spring 4;

(4) Taking the excitation sleeve 3, comparing the lower part of the excitation sleeve 3 with the top part of the spring 4, accommodating the upper part of the spring 4 into the spring accommodating cavity 32, and enabling the top part of the spring 4 to prop against the lower surface of the spring seat 33 so as to limit the top part of the spring 4;

compressing the excitation sleeve 3 downwards to enable the excitation sleeve 3 to enter the mounting table 14 of the shell 1, and aligning the guide groove 34 with the guide protrusion 15; continuing to compress the energizing sleeve 3 downwards, the spring 4 is further compressed, the guide projection 15 snaps into the guide groove 34, and the guide post 23 is received in the energizing groove 36, and the guide post 23 is made to abut against the energizing inclined surface 37, i.e. a space-like guide cam mechanism is formed between the guide post 23 and the energizing inclined surface 37.

Namely, the assembly of the protective device for the injector of the utility model is completed, and the state shown in figure 1 is formed; at this time, the energizing sleeve 3 is held against the spring 4 and is not in a fixed state, and the spring 4 is released to eject the energizing sleeve 3 from the housing 1 upon releasing the force applied to the energizing sleeve 3.

To lock the trigger sleeve 3, a disposable prefilled syringe is further required to be filled, and the state shown in fig. 2 and 12 is formed, namely, the assembly process of the disposable safety syringe of the utility model is as follows:

taking a disposable prefilled syringe, aligning the needle 53 of the syringe with the protective device for the syringe, inserting the needle 53 into the trigger sleeve 3 and penetrating the spring 4 into the syringe accommodating cavity 22 of the protective inner sleeve 2, and enabling the needle 51 of the syringe to penetrate the syringe accommodating cavity 22 and reach the outside of the protective inner sleeve 2; the flange 52 of the syringe is fitted into the mounting block 14 such that the bottom of the flange 52 is in contact with the top of the trigger sleeve 3, the flange 52 is fully seated in the movable space 141, and the flange 52 is restrained by a solid portion of the mounting block 14 because the flange 52 has a larger cross-sectional dimension than the mounting block 14, and at this time, the flange 52 is released, and is also retained in the mounting block 14, thereby forming a fixation, while the trigger sleeve 3 is restrained by the flange 52, thereby temporarily fixing, and the spring 4 is compressed.

The spring 4 provides elastic force to press the top surface of the flange 52 against the top of the movable space 141, and is limited by the mounting body at the upper part of the mounting table 14. At this time, the plunger 6 of the syringe is not pushed, and the piston 62 at the bottom of the plunger 6 is located at the upper portion of the cylinder 51, in which the medicine is stored.

When the disposable safety syringe is used, similar to a common syringe, the shell 1 is grasped, the needle 53 is pricked into a patient, and the downward force grasping the shell 1 in the process is completely applied to the needle 53 through the mounting table 14, the flange 52 and the syringe 51; the finger then grips the lower part of the handle tab 13 and the other 1 finger is pressed against the push head 61 on top of the push rod 6, exerting a force, the push rod 6 pushing the bottom piston 62 to move in the barrel 51, thereby injecting the medicament into the patient through the needle 53.

As shown in fig. 13 and 14, when the injection of the disposable safety syringe of the present utility model is completed, the piston 62 reaches the end of the cylinder 51, and the push head 61 is located outside the mounting table 14; after the injection is completed, the injector is driven to move upwards integrally, and the needle 53 is pulled out of the patient.

After the needle is pulled out, the pushing head 61 is still forced, so that the pushing rod 6 drives the piston 62 to move downwards, and the piston 62 pushes the needle cylinder 51 to move downwards along with the needle cylinder 1, and then the flange 52 moves downwards along with the needle cylinder; the flange 52 moves downwards together with the energizing sleeve 3, the spring 4 is further compressed (as shown in fig. 15), the energizing sleeve 3 moves vertically downwards relative to the housing 1 under the limit of the guide protrusion 15 and the guide groove 34, the energizing inclined surface 37 presses the guide post 23 of the protective inner sleeve 2 downwards in the process, so that the guide post 23 slides along the energizing inclined surface 37, and the guide post 23 moves diagonally relative to the housing 1 due to the abutment of the limiting ring 24 of the protective inner sleeve 2 on the limiting protrusion 16 in the process, which is the fact that the energizing sleeve 3 moves downwards relative to the housing 1, and the protective inner sleeve 2 rotates relative to the housing 1, as shown in fig. 16.

The pushing head 61 is forced to move by one end distance until the flange 52 moves downwards to approach the handle wing piece 13, namely, as shown in fig. 17, 18, 19 and 20, the limiting ring 24 of the protective inner sleeve 2 reaches the position of the limiting boss 16 along with rotating to the position of the opening 25, at the moment, the limiting ring 24 of the protective inner sleeve 2 loses the limit of the limiting boss 16, the spring 4 is instantly released, the protective inner sleeve 2 is pushed downwards relative to the shell 1, namely, as shown in fig. 21, the limiting ring 24 passes over the limiting boss 16 and reaches the lower part of the limiting boss 16; the spring 4 continues to release, continuing to push the inner protective sleeve 2 downwardly relative to the outer shell 1, as shown in fig. 22 and 23.

Finally, under the action of the spring 4, the limiting ring 24 passes over the locking elastic sheet 17 (extrudes the guide inclined surface 172 and moves downwards along the guide inclined surface 173 to push the locking elastic sheet 17 outwards), enters the locking cavity 19, finally abuts against the limiting boss 18, and the locking elastic sheet 17 automatically resets to clamp the limiting ring 24 of the protective inner sleeve 2 in the locking cavity 19 (the thickness of the limiting ring 24 is smaller than the height of the locking cavity 19), so that the protective inner sleeve 2 is fixed; the bottom of the protective inner sleeve 2 fully extends relative to the shell 1, so that the needle 53 of the syringe is fully covered, and the needle 53 of the used syringe is fully protected.

The force on the push head 61 is removed, the spring 4 also pushes the excitation sleeve 3 to reset upwards, the excitation sleeve 3 drives the flange 52 to move upwards in the movable space 141, and finally the top of the flange 52 abuts against the lower part of the entity at the top of the mounting table 14, so that the limit is obtained. The flange 52 carries the syringe up to reset and also causes the needle 53 to be properly raised, further increasing the safety distance.

That is, the final release is completed, and the state shown in fig. 24, 25 and 26 is formed.

The inner diameter of the injector accommodating cavity 22 of the protective inner sleeve 2 is equal to the outer diameter of the needle cylinder 51 of the injector, and the inner diameter and the outer diameter can move freely relatively; the outer diameter of the limiting ring 24 of the protective inner sleeve 2 is slightly smaller than the inner diameter of the inner sleeve accommodating cavity 12 of the shell 11, and the limiting ring and the inner sleeve can move freely relatively.

While the preferred embodiments of the present utility model have been described in detail, the present utility model is not limited to the embodiments described above, and various equivalent modifications and substitutions can be made by those skilled in the art without departing from the spirit of the present utility model, and these are intended to be included in the scope of the present utility model as defined in the appended claims.

Claims (10)

1. The protective device for the injector is characterized by comprising a shell, a protective inner sleeve, an excitation ring and a spring;

the lower part of the main body is a shell of a thin-wall cylinder, a cylindrical inner sleeve accommodating cavity is formed in the shell, and the inner sleeve accommodating cavity is vertically communicated; handle fins extending outwards from two sides are arranged above the shell; the top of the shell is provided with a mounting table which is of a hollow structure, and the mounting table forms a hollow movable space above the handle wing pieces;

the upper side of the inner part of the shell is respectively provided with a guide bulge and a limit bulge; wherein, the guide bulge is arranged close to the mounting table and is positioned at the top of the inner side of the shell; the limiting bulge is positioned at the middle upper part of the shell, and a space is arranged between the limiting bulge and the guide bulge;

the lower part of the shell is provided with a locking spring piece, and a limit boss is arranged below the locking spring piece; a locking cavity is formed between the locking spring plate and the limiting boss;

the locking spring piece is a cantilever spring piece arranged along the outer wall of the shell, three sides of the locking spring piece are hollowed out to form a yielding groove, the fixed end of the locking spring piece is arranged along the radial direction of the shell, the fixed end of the locking spring piece is positioned above, and the lower part of the locking spring piece is a movable end; the lower part of the locking spring plate protrudes inwards to form a locking boss, and the upper part of the locking boss is provided with a guide inclined surface which is arranged downwards and inwards;

the limiting boss is a horizontally arranged platform and protrudes towards the inner wall of the shell;

the shell is internally provided with an excitation assembly consisting of a protective inner sleeve, an excitation sleeve and a spring;

the excitation sleeve is a thin-wall cylinder, and a cylindrical spring accommodating cavity is arranged on the inner side of the excitation sleeve; the upper part of the excitation sleeve is a guide cylinder, the top of the guide cylinder extends inwards to form a spring seat, and the top of the spring accommodating cavity is partially sealed to form top limit of the spring; the wall surface of the guide cylinder is provided with a guide groove, the guide groove is arranged along the axial direction of the excitation sleeve and penetrates through the axial direction of the guide cylinder, the guide groove is internally provided with a guide bulge of the shell, and the guide groove and the guide bulge can move relatively; the lower part of the excitation sleeve is an excitation cylinder, an excitation groove penetrating through the wall surface is arranged on the excitation cylinder, and an excitation inclined plane which is arranged obliquely upwards is arranged in the excitation groove;

the protective inner sleeve is a thin-wall cylinder, and a syringe accommodating cavity which penetrates up and down is arranged in a cylinder shell of the protective inner sleeve; the upper part of the cylinder shell is provided with a guide post which protrudes outwards; the upper middle part of the cylinder shell is provided with a limiting ring which protrudes outwards, and the limiting ring is provided with an opening;

the width of the limiting bulge is smaller than the width of the opening and smaller than the width of the locking spring plate;

the top of the cylinder shell is a supporting surface of the spring;

the spring is a compression spring and is always in a compression state;

the protective inner sleeve is positioned in the inner sleeve accommodating cavity of the shell; before excitation, a limiting ring of the protective inner sleeve is propped against the upper part of the limiting bulge, and the opening is far away from the limiting bulge; before excitation, the guide post is clamped into the excitation groove and is propped against the excitation inclined plane;

when the device is excited, the opening of the limiting ring is consistent with the position of the limiting bulge;

after excitation, the limiting ring is positioned in the locking cavity, and the lower part of the protective inner sleeve protrudes out of the outer shell;

the spring is positioned between the supporting surface of the protective inner sleeve and the spring seat of the excitation sleeve.

2. The guard for the syringe as claimed in claim 1, wherein 2 guide protrusions and limit protrusions are provided on the inner side of the housing;

the guide protrusions and the limit protrusions are symmetrically arranged on the inner side wall surface of the shell;

the guide protrusions and the limit protrusions are narrow protrusions;

the width of the guide protrusion is smaller than the width of the opening;

the opening on the limiting ring of the protective inner sleeve is provided with 2 parts, the two parts are symmetrically arranged on the limiting ring, and the position of the opening corresponds to the limiting bulge.

3. The guard for a syringe of claim 1 or 2, wherein the guide projection and the limit projection are in the same orientation as the inner wall of the housing.

4. The guard for the syringe of claim 1, wherein the locking spring is provided with 2 parts symmetrically arranged on the housing.

5. The protective device for the injector according to claim 1, wherein the excitation groove and the excitation inclined plane on the excitation sleeve are provided with 2 parts and are symmetrically arranged in the wall surface of the excitation cylinder;

the number of the guide posts is 2, and the guide posts are symmetrically arranged on the outer wall of the cylinder shell;

the setting position of the guide post corresponds to the excitation inclined plane.

6. The guard for the syringe of claim 1 wherein the outer diameter of the guard inner sleeve stop collar is less than the inner diameter of the inner sleeve receiving cavity of the housing, the guard inner sleeve and the housing being relatively free to move therebetween.

7. The guard for the syringe of claim 1, wherein the stop collar has a thickness less than a height of the locking cavity.

8. A disposable safety syringe comprising a protector for a syringe according to any one of claims 1 to 7, in which a disposable prefilled syringe is mounted;

the flange of the injector is arranged in the mounting table and is positioned above the excitation sleeve; the needle cylinder is positioned in the injector accommodating cavity of the protective inner sleeve;

before the disposable safety syringe is used, the needle of the syringe passes through the protective device for the syringe and is positioned at the outer side of the protective inner sleeve;

after the disposable safety syringe is used, the lower part of the protective inner sleeve passes over the needle of the syringe after the protective device for the syringe is completely excited, and the needle of the syringe is wrapped in the syringe accommodating cavity.

9. The single use safety syringe of claim 8 wherein the length of the plunger is longer than the length of the barrel;

after the injection of the medicament in the needle cylinder is finished, the push head of the push rod is positioned above the mounting table or positioned at the upper part of the mounting table.

10. The disposable safety syringe according to claim 8, wherein the inner diameter of the syringe receiving chamber of the protective sleeve is larger than the outer diameter of the barrel of the syringe, the protective sleeve and the barrel being relatively freely movable.