CN212880456U - Medical needle type injection system - Google Patents

Abstract

The utility model discloses a medical needle injection system, which comprises a pen container and a quantitative propellant component arranged in the pen container, wherein the quantitative propellant component comprises a push rod seat arranged in the pen container, a push rod matched with a lead screw of the push rod seat, a transmission rod sleeved outside the push rod, a clutch transmission shaft sleeved outside the transmission rod, a dose cylinder sleeved outside the clutch transmission shaft and a button arranged at the top of the pen container; the transmission rod is arranged on the inner wall of the pen container in an axial limiting mode and can rotate along the axis of the transmission rod in a fixed axis one-way mode; and when and only when the button is subjected to axial pressure, the convex position is tightly clamped with the tooth grooves of the end face teeth. The medical needle type injection system can realize the retraction operation of the push rod only by pressing the push rod, and the operation is simple and convenient; and the push rod only can drive the push rod seat to rotate, and the transmission rod and the clutch transmission shaft cannot rotate, so that the problem of jamming is avoided.

Description

Medical needle type injection system

Technical Field

The utility model relates to the technical field of medical equipment, especially, relate to a medical needle type injection system.

Background

At present, a disposable sterile injector is mainly used for medicine injection in the market, but the injection process needs hospital treatment and is operated and injected by professional personnel, and the operation convenience is not suitable for self management of most chronic disease patients.

At present, the purely mechanical injection pen has the optimal safety and reliability in the structures of screw transmission, clutch transmission, tactile feedback and the like in the process of realizing accurate distribution of medicines.

At present, injection pens capable of being used repeatedly exist in the market, the price is high, the service life is short, the operation of pushing the push rod back is complex, the operation is not good, the push rod is easy to block, and the using effect is not good.

In summary, how to solve the problem that the retraction operation of the plunger of the injection pen is complex and easy to be locked has become a technical problem that needs to be solved urgently by those skilled in the art.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a medical needle type injection system to solve the push rod of injection pen and return the complicated and dead problem of easy card of operation.

In order to achieve the above object, the utility model provides a medical needle injection system, including pen container and the quantitative propellant subassembly that sets up in the pen container, the quantitative propellant subassembly includes the push rod seat that sets up in the pen container, with push rod seat lead screw complex push rod, cover establish in the transfer line of the push rod outside, cover establish in the clutch transmission shaft of the transfer line outside, cover establish in the dose canister of the clutch transmission shaft outside and set up the button at the top of the pen container;

the push rod seat can axially slide in the pen container and can axially rotate with the fixed shaft, and when the push rod seat slides to a preset position, the push rod seat is linked with the transmission rod; when the push rod seat is separated from the preset position, the push rod seat is separated from linkage with the transmission rod; an elastic piece is arranged between the push rod seat and the pen container and is used for enabling the push rod seat to have a movement trend of moving away from the preset position;

the push rod penetrates through the push rod seat and is connected with the push block of the medicine bin, and when the medicine bin is installed in place, the medicine bin pushes the push rod seat to slide to the preset position;

the transmission rod is arranged on the inner wall of the pen container in an axial limiting mode and can rotate along the axis of the transmission rod in a fixed axis one-way mode;

the clutch transmission shaft is in axial sliding fit with the transmission rod and circumferentially limits rotation;

a circle of end face teeth are arranged on the inner end face of the barrel bottom of the dosage barrel, at least one protruding position matched with the tooth grooves in the end face teeth is arranged at one end, close to the barrel bottom, of the clutch transmission shaft, the dosage barrel can be screwed into and screwed out of the pen container, and the screwing direction of the dosage barrel is the same as the unidirectional rotation direction of the fixed shaft of the transmission rod;

the button is used for applying axial pressure to the clutch transmission shaft; and when and only when the button is subjected to axial pressure, the protruding position is tightly clamped with the tooth groove of the end face tooth.

Preferably, the outer wall of the transmission rod is provided with an annular clamping groove, and the pen container is internally provided with an annular clamping plate which is matched with the annular clamping groove to realize axial limiting.

Preferably, the inner ring of the annular clamping plate is provided with a guide angle for facilitating the transmission rod to pass through.

Preferably, a one-way limiting bulge is arranged on the outer end face of the bottom of the dosage cylinder, a limiting blocking groove matched with the one-way limiting bulge is arranged on the annular clamping plate, and when the dosage cylinder is screwed into a return-to-zero position, the one-way limiting bulge and the limiting blocking groove complete blocking matching; or, the outer end face of the bottom of the dosage cylinder is provided with a limiting blocking groove, the annular clamping plate is provided with a one-way limiting bulge matched with the limiting blocking groove, and when the dosage cylinder is screwed into the zero return position, the one-way limiting bulge and the limiting blocking groove complete blocking matching.

Preferably, when the one-way limiting protrusion and the limiting blocking groove complete the blocking matching, a preset gap is formed between the outer end face of the bottom of the dose cylinder and the corresponding face of the annular clamping plate.

Preferably, the quantitative pesticide pushing assembly further comprises a transmission gear shaft fixedly connected with the button, a pinion is arranged on the transmission gear shaft, an elastic tooth piece is arranged at one end, close to the button, of the clutch transmission shaft, and the elastic tooth piece and the pinion are in ratchet wheel type one-way meshing.

Preferably, the elastic tooth piece and the clutch transmission shaft are of an integrated structure.

Preferably, the transmission gear shaft is further provided with a large gear which is coaxially arranged with the small gear, one end of the dosage barrel, which is close to the button, is fixedly provided with a spring gear sleeve, and the spring gear sleeve and the large gear are in ratchet type one-way meshing.

Preferably, the quantitative propellant component further comprises a knob fixedly connected with the outer wall of the dosage drum, and the button can freely rotate and penetrate through the knob.

Preferably, a fixing sleeve is embedded in the pen container, and the dosage cylinder is in threaded fit with the fixing sleeve.

Compared with the introduction content of the background technology, the medical needle type injection system comprises a pen container and a quantitative propellant component arranged in the pen container, wherein the quantitative propellant component comprises a push rod seat arranged in the pen container, a push rod matched with a lead screw of the push rod seat, a transmission rod sleeved outside the push rod, a clutch transmission shaft sleeved outside the transmission rod, a dosage cylinder sleeved outside the clutch transmission shaft and a button arranged at the top of the pen container; the push rod seat can axially slide in the pen container and can rotate with the fixed shaft, and when the push rod seat slides to a preset position, the push rod seat is linked with the transmission rod; when the push rod seat is separated from the preset position, the push rod seat is separated from linkage with the transmission rod; an elastic piece is arranged between the push rod seat and the pen container and is used for enabling the push rod seat to have a movement trend of moving away from a preset position; the push rod penetrates through the push rod seat and is connected with the push block of the medicine bin, and when the medicine bin is installed in place, the medicine bin pushes the push rod seat to slide to a preset position; the transmission rod is arranged on the inner wall of the pen container in an axial limiting mode and can rotate along the axis of the transmission rod in a fixed axis one-way mode; the clutch transmission shaft is in axial sliding fit with the transmission rod and circumferentially limits rotation; a circle of end face teeth are arranged on the inner end face of the barrel bottom of the dosage barrel, at least one protruding position matched with the tooth grooves in the end face teeth is arranged at one end, close to the barrel bottom of the dosage barrel, of the clutch transmission shaft, the dosage barrel can be screwed into and out of the pen barrel, and the screwing direction of the dosage barrel is the same as the one-way rotating direction of the fixed shaft of the transmission rod; the button is used for applying axial pressure to the clutch transmission shaft; and when and only when the button is subjected to axial pressure, the convex position is tightly clamped with the tooth grooves of the end face teeth. The medical needle-type injection system is characterized in that a clutch transmission shaft is arranged between a transmission rod and a dosage drum, the clutch transmission shaft and the transmission rod are in axial sliding fit and are limited in rotation in the circumferential direction, the clutch transmission shaft and the dosage drum are matched with each other through a structure of a convex position and an end surface tooth, and when and only when the button is subjected to axial pressure, the convex position is tightly clamped with a tooth socket of the end surface tooth, so when the dosage drum sets dosage, namely when the dosage drum is screwed out, the transmission rod can only rotate around the axis of the transmission rod along the screwing-in direction fixed shaft of the dosage drum in one direction, therefore, when the dosage drum is screwed out, the transmission rod has limited rotation effect on the clutch transmission shaft, and under the condition that the button is not subjected to the axial pressure, the convex position and the tooth socket of the end surface tooth are not tightly clamped, then the clutch transmission shaft can be lifted to slide outwards relative to the transmission rod, therefore, the push rod cannot move, and the process can smoothly complete the dose setting; when the injection dosage barrel is used for setting dosage, the button is pressed to force the dosage barrel to be screwed in, and because the convex position is tightly clamped with the end face teeth at the moment, the clutch rotating shaft can rotate along with the dosage barrel, the medicine bin is installed in place at the moment, the push rod seat is in the preset position, the push rod seat and the transmission rod rotate in a linkage manner, and then the push rod matched with the lead screw of the push rod seat can drive the push block to push the medicine bin; when the medicine bin is required to be replaced to return the push rod, the push rod seat is separated from the preset position under the action of the elastic piece, and the transmission rod is arranged on the inner wall of the pen container in an axial limiting mode, so that the push rod seat is separated from the transmission rod in a linkage relation, and the push rod can be returned only by pressing the push rod, and the operation is simple and convenient; and the push rod only can drive the push rod seat to rotate, and the transmission rod and the clutch transmission shaft cannot rotate, so that the problem of jamming is avoided.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a cross-sectional view of the overall structure of a medical needle injection system according to an embodiment of the present invention;

fig. 2 is an exploded view of the overall structure of a medical needle injection system according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a transmission rod according to an embodiment of the present invention;

fig. 4 is a schematic structural view of a dose measuring cylinder according to an embodiment of the present invention;

fig. 5 is a schematic structural view of an end face tooth arranged on an inner end face of the dose cylinder provided by the embodiment of the present invention;

fig. 6 is a schematic structural view of a ring-shaped clamping plate provided with a limiting groove according to an embodiment of the present invention;

fig. 7 is a schematic structural view of a clutch transmission shaft according to an embodiment of the present invention;

fig. 8 is a schematic structural view of a spring tooth sleeve provided in an embodiment of the present invention;

fig. 9 is a schematic structural view of a transmission gear shaft according to an embodiment of the present invention.

In the above figures 1-9 of the drawings,

the pen container comprises a pen container 1, a push rod seat 2, a push rod 3, a transmission rod 4, a clutch transmission shaft 5, a dosage container 6, a button 7, an elastic part 8, a medicine bin 9, a push block 10, end face teeth 11, a protrusion position 12, an annular clamping groove 13, an annular clamping plate 14, a one-way limiting protrusion 15, a limiting blocking groove 16, a transmission gear shaft 17, a small gear 17a, a large gear 17b, an elastic tooth piece 18, an elastic tooth sleeve 19, a knob 20 and a fixing sleeve 21.

Detailed Description

The core of the utility model is to provide a medical needle type injection system to solve the problem that the push rod of the injection pen returns to operate complicatedly and block easily.

In order to make those skilled in the art better understand the technical solutions provided by the present invention, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1-9, the embodiment of the present invention provides a medical needle injection system, which is characterized in that the medical needle injection system comprises a pen container 1 and a quantitative propellant component arranged in the pen container 1, wherein the quantitative propellant component comprises a push rod base 2 arranged in the pen container 1, a push rod 3 matched with a lead screw of the push rod base 2, a transmission rod 4 sleeved outside the push rod 3, a clutch transmission shaft 5 sleeved outside the transmission rod 4, a dosage barrel 6 sleeved outside the clutch transmission shaft 5, and a button 7 arranged at the top of the pen container 1; the push rod seat 2 can axially slide and axially rotate in the pen container 1, and when the push rod seat 2 slides to a preset position, the push rod seat 2 is linked with the transmission rod 4; when the push rod seat 2 is separated from the preset position, the push rod seat 2 is separated from linkage with the transmission rod 4; an elastic piece 8 is arranged between the push rod seat 2 and the pen container 1, and the elastic piece 8 is used for enabling the push rod seat 2 to have a movement trend of moving to a position away from a preset position; the push rod 3 penetrates through the push rod seat 2 and is connected with the push block 10 of the medicine bin 9, and when the medicine bin 9 is installed in place, the medicine bin 9 pushes the push rod seat 2 to slide to a preset position; the transmission rod 4 is arranged on the inner wall of the pen container 1 in an axial limiting mode, and the transmission rod 4 can rotate along the axis of the transmission rod 4 in a fixed-axis one-way mode; the clutch transmission shaft 5 is in axial sliding fit with the transmission rod 4 and circumferentially limits rotation; a circle of end face teeth 11 are arranged on the inner end face of the barrel bottom of the dosage barrel 6, at least one protruding position 12 matched with tooth grooves in the end face teeth 11 is arranged at one end, close to the barrel bottom of the dosage barrel 6, of the clutch transmission shaft 5, the dosage barrel 6 can be screwed into and out of the pen barrel 1, and the screwing direction of the dosage barrel 6 is the same as the direction of one-way rotation of the fixed shaft of the transmission rod 4; the button 7 is used for applying axial pressure to the clutch transmission shaft 5; the raised portion 12 is in tight engagement with the gullet of the face teeth 11 if and only if the button 7 is subjected to axial pressure.

The medical needle-type injection system is characterized in that a clutch transmission shaft is arranged between a transmission rod and a dosage drum, the clutch transmission shaft and the transmission rod are in axial sliding fit and are limited in rotation in the circumferential direction, the clutch transmission shaft and the dosage drum are matched with each other through a structure of a convex position and an end surface tooth, and when and only when the button is subjected to axial pressure, the convex position is tightly clamped with a tooth socket of the end surface tooth, so when the dosage drum sets dosage, namely when the dosage drum is screwed out, the transmission rod can only rotate around the axis of the transmission rod along the screwing-in direction fixed shaft of the dosage drum in one direction, therefore, when the dosage drum is screwed out, the transmission rod has limited rotation effect on the clutch transmission shaft, and under the condition that the button is not subjected to the axial pressure, the convex position and the tooth socket of the end surface tooth are not tightly clamped, then the clutch transmission shaft can be lifted to slide outwards relative to the transmission rod, therefore, the push rod cannot move, and the process can smoothly complete the dose setting; when the injection dosage barrel is used for setting dosage, the button is pressed to force the dosage barrel to be screwed in, and because the convex position is tightly clamped with the end face teeth at the moment, the clutch rotating shaft can rotate along with the dosage barrel, the medicine bin is installed in place at the moment, the push rod seat is in the preset position, the push rod seat and the transmission rod rotate in a linkage manner, and then the push rod matched with the lead screw of the push rod seat can drive the push block to push the medicine bin; when the medicine bin is required to be replaced to return the push rod, the push rod seat is separated from the preset position under the action of the elastic piece, and the transmission rod is arranged on the inner wall of the pen container in an axial limiting mode, so that the push rod seat is separated from the transmission rod in a linkage relation, and the push rod can be returned only by pressing the push rod, and the operation is simple and convenient; and the push rod only can drive the push rod seat to rotate, and the transmission rod and the clutch transmission shaft cannot rotate, so that the problem of jamming is avoided.

It should be noted here that, the specific structural form of the linkage between the push rod seat 2 and the transmission rod 4 may be that a transmission ring is arranged on one side of the push rod seat 2 facing the transmission rod 4, the specific structural form of the transmission ring may be a clamping structure, a protruding card matched with the clamping position is arranged on the transmission rod 4, the medicine bin may be pushed to one side of the push rod seat 2 away from the transmission rod during installation, after the medicine bin is installed in place, the clamping position on the push rod seat is just matched with the protruding card, and at this time, the linkage between the push rod seat and the transmission rod may be realized. It can be understood that, the above-mentioned engaging manner of the engaging position and the protruding clip is merely a preferred example of the embodiment of the present invention for the linkage structure, and in the practical application process, other common linkage engaging structures may also be selected, which is not limited herein more specifically. In addition, the elastic piece is arranged between the push rod seat and the pen container, so that when the medicine bin is not installed, the push rod seat can be automatically and smoothly separated from the transmission rod due to the fact that the transmission rod is arranged on the pen container in an axial limiting mode, when the push rod is retracted, the phenomenon of mutual interference between the push rod seat and the transmission rod cannot occur, and the phenomenon of blocking is avoided.

In addition, the specific structural form that the transmission rod can rotate in a single direction along the axis fixed shaft of the transmission rod can be that a ratchet ring is arranged between the transmission rod and the inner wall of the pen container so as to realize the single-direction rotation.

In some specific embodiments, the specific structural form of the transmission rod for realizing the axial limit on the pen container may be that an annular clamping groove 13 may be arranged on the outer wall of the transmission rod 4, and an annular clamping plate 14 for cooperating with the annular clamping groove 13 to realize the axial limit is arranged in the pen container 1. It can be understood that the above structure is only a preferred example for realizing the axial limiting structure, and in the practical application process, the projection structure may be directly arranged on the transmission rod, and the inner wall of the pen container is provided with a groove structure adapted to the projection structure. In the practical application process, the selection can be carried out according to the practical requirements.

In a further embodiment, in order to facilitate the installation of the transmission rod into the annular clamping plate and to achieve the axial positioning of the transmission rod and the annular clamping plate, a guide angle for facilitating the transmission rod 4 to pass through may be further provided on the inner ring of the annular clamping plate 14.

In some specific embodiments, the dosage cylinder 6 may be provided with a one-way limiting protrusion 15 on the outer end surface of the bottom, the annular clamping plate 14 is provided with a limiting blocking groove 16 matched with the one-way limiting protrusion 15, and when the dosage cylinder 6 is screwed into the return-to-zero position, the one-way limiting protrusion 15 and the limiting blocking groove 16 complete blocking matching; or, the outer end face of the bottom of the dosage barrel 6 is provided with a limiting stop groove 16, the annular clamping plate 14 is provided with a one-way limiting bulge 15 matched with the limiting stop groove 16, and when the dosage barrel 6 is screwed into the return-to-zero position, the one-way limiting bulge 15 and the limiting stop groove 16 complete stop matching. Through the structure that sets up one-way spacing arch and spacing groove of keeping off, can realize the accurate location of dosing section of thick bamboo zero return position, avoid because of the influence of dosing section of thick bamboo thread machining precision, lead to the inaccurate problem in zero return position.

In a further embodiment, when the one-way limiting projection 15 and the limiting stop groove 16 complete stop matching, the bottom outer end surface of the dosage drum 6 has a preset clearance with the corresponding surface of the ring-shaped clamping plate 14. Through setting up this clearance of predetermineeing for the return to zero position of dose cylinder only needs to be decided by the cooperation of one-way spacing arch and spacing groove of keeping off, has avoided the problem of the processing degree of difficulty increase that the multiple spacing of return to zero position leads to.

In some specific embodiments, the quantitative reagent pushing assembly may further include a transmission gear shaft 17 fixedly connected to the button 7, a pinion 17a is disposed on the transmission gear shaft 17, an elastic gear 18 is disposed at an end of the clutch transmission shaft 5 close to the button 7, and the elastic gear 18 and the pinion 17a are in ratchet type one-way engagement. Through the ratchet type one-way meshing of the elastic tooth piece 18 and the pinion 17a, when the dosage barrel is screwed in, the sound of tooth groove switching meshing can be generated along with the rotation of the clutch transmission shaft, and the sound is used as a sound prompt.

In a further embodiment, the elastic tooth plate 18 and the clutch transmission shaft 5 may be an integral structure, for example, directly formed by machining on the clutch transmission shaft 5; or a split fixed structure, for example, fixed on the clutch transmission shaft by welding or fixed by other fastening methods.

In some more specific embodiments, the driving gear shaft 17 may further be provided with a large gear 17b coaxially arranged with the small gear 17a, and one end of the dose cylinder 6 near the button 7 is fixedly provided with a spring gear sleeve 19, and the spring gear sleeve 19 and the large gear 17b are in ratchet type one-way engagement. Through the structure that sets up gear wheel and bullet tooth cover for when the dosage cylinder was unscrewed, can send the sound that the tooth's socket switched meshing along with the rotation of dosage cylinder, remind as the sound.

In some more specific embodiments, the dosing and expelling assembly may further comprise a knob 20 fixedly connected to the outer wall of the dose barrel 6, the button 7 being freely rotatable through the knob 20. The rotary operation of the dose cylinder is more convenient by arranging the knob.

In a further embodiment, in order to facilitate the structure of the dose cylinder and the pen barrel to realize the screwing fit, a fixing sleeve 21 may be embedded in the pen barrel 1, and the dose cylinder 6 is in threaded fit with the fixing sleeve 21. Through setting up fixed cover, can reduce the processing degree of difficulty on the one hand, on the other hand can avoid the serious pen container life who leads to of wearing and tearing low problem between dose tube and the pen container.

The medical needle-type injection system provided by the utility model is described in detail above. It should be noted that, in the present specification, the embodiments are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

It is also noted that, in this document, terms such as "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in an article or device that comprises the element.

The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of the embodiments are only used to help understand the core concepts of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.

Claims (10)

1. A medical needle type injection system is characterized by comprising a pen container (1) and a quantitative propellant component arranged in the pen container (1), wherein the quantitative propellant component comprises a push rod seat (2) arranged in the pen container (1), a push rod (3) matched with a lead screw of the push rod seat (2), a transmission rod (4) sleeved on the outer side of the push rod (3), a clutch transmission shaft (5) sleeved on the outer side of the transmission rod (4), a dose cylinder (6) sleeved on the outer side of the clutch transmission shaft (5) and a button (7) arranged at the top of the pen container (1);

the push rod seat (2) can axially slide and axially rotate in the pen container (1), and when the push rod seat (2) slides to a preset position, the push rod seat (2) is linked with the transmission rod (4); when the push rod seat (2) is separated from the preset position, the push rod seat (2) is separated from linkage with the transmission rod (4); an elastic piece (8) is arranged between the push rod seat (2) and the pen container (1), and the elastic piece (8) is used for enabling the push rod seat (2) to have a movement trend of moving away from the preset position;

the push rod (3) penetrates through the push rod seat (2) and is connected with a push block (10) of the medicine bin (9), and when the medicine bin (9) is installed in place, the medicine bin (9) pushes the push rod seat (2) to slide to the preset position;

the transmission rod (4) is arranged on the inner wall of the pen container (1) in an axial limiting mode, and the transmission rod (4) can rotate along the axis of the transmission rod (4) in a fixed-axis one-way mode;

the clutch transmission shaft (5) is in axial sliding fit with the transmission rod (4) and circumferentially limits rotation;

a circle of end face teeth (11) are arranged on the inner end face of the bottom of the dosage cylinder (6), at least one protruding position (12) matched with tooth grooves in the end face teeth (11) is arranged at one end, close to the bottom of the dosage cylinder (6), of the clutch transmission shaft (5), the dosage cylinder (6) can be screwed into and out of the pen container (1), and the screwing direction of the dosage cylinder (6) is the same as the fixed-axis one-way rotation direction of the transmission rod (4);

the button (7) is used for applying axial pressure to the clutch transmission shaft (5); and when and only when the button (7) is subjected to axial pressure, the protruding part (12) is tightly clamped with the tooth groove of the end face tooth (11).

2. A medical needle injection system according to claim 1, wherein an annular groove (13) is provided on the outer wall of the transmission rod (4), and an annular snap plate (14) for cooperating with the annular groove (13) to realize axial limit is provided in the barrel (1).

3. A medical needle injection system according to claim 2, wherein the inner ring of the ring-shaped catch plate (14) is provided with a guide angle for facilitating the penetration of the transmission rod (4).

4. A medical needle-type injection system according to claim 2, wherein the dosage cylinder (6) is provided with a one-way limiting protrusion (15) on the outer end surface at the bottom, the ring-shaped snap plate (14) is provided with a limiting groove (16) matched with the one-way limiting protrusion (15), and when the dosage cylinder (6) is rotated to the zero position, the one-way limiting protrusion (15) and the limiting groove (16) complete the stopping fit; or, the outer end face of the bottom of the dose cylinder (6) is provided with a limiting blocking groove (16), the annular clamping plate (14) is provided with a one-way limiting protrusion (15) matched with the limiting blocking groove (16), and when the dose cylinder (6) is screwed into a return-to-zero position, the one-way limiting protrusion (15) and the limiting blocking groove (16) complete blocking matching.

5. A medical needle-type injection system according to claim 4, wherein the bottom outer end face of the dose cylinder (6) has a predetermined clearance with the corresponding face of the ring-shaped catch plate (14) when the one-way stopper protrusion (15) is brought into stop engagement with the stopper groove (16).

6. A medical needle injection system according to claim 1, wherein the quantitative pushing-dose assembly further comprises a transmission gear shaft (17) fixedly connected with the button (7), a pinion (17a) is arranged on the transmission gear shaft (17), an elastic toothed plate (18) is arranged at one end of the clutch transmission shaft (5) close to the button (7), and the elastic toothed plate (18) and the pinion (17a) are in ratchet type one-way engagement.

7. A medical needle injection system according to claim 6, wherein said resilient blade (18) is of one-piece construction with said clutch drive shaft (5).

8. A medical needle injection system according to claim 6, wherein the transmission gear shaft (17) is further provided with a gearwheel (17b) coaxially arranged with the pinion (17a), one end of the dose cylinder (6) close to the button (7) is fixedly provided with a spring gear sleeve (19), and the spring gear sleeve (19) and the gearwheel (17b) are in ratchet type one-way engagement.

9. A medical needle injection system according to claim 1, wherein the dosing assembly further comprises a knob (20) fixedly connected to an outer wall of the dose cylinder (6), the button (7) being freely rotatable through the knob (20).

10. Medical needle injection system according to any of claims 1 to 9, wherein a harness (21) is embedded in said barrel (1) and said dosage cylinder (6) is screw-engaged with said harness (21).

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