CN116764036B - Quantitative injection device - Google Patents

Abstract

The invention belongs to the technical field of medical instruments, namely pen-type injectors, and particularly relates to a quantitative injection device. The invention sets the fixed ratchet wheel, the pawl-tube combination unit, the slotted screw unit, the movable ratchet wheel unit and the rotary pawl unit on the shell unit, so that: 1. each rotation action of the rotating pawl unit is a fixed angle, and the pawl-tube combination unit is driven to rotate by a fixed angle, so that each advancing distance of the slotted screw unit is fixed, and the aim of quantitative injection is finally fulfilled; 2. after one injection operation, the reverse rotation reset angle of the rotary pawl unit is fixed, and the pawl-tube combination unit is not driven to reversely rotate together, so that the gap slotting screw unit for the injection operation is ensured to be completely fixed.

Description

Dosing injection device

Technical Field

The invention belongs to the technical field of medical devices-pen-type injectors, and in particular relates to a quantitative injection device.

Background technique

A quantitative injection device refers to a new type of syringe that can eject equal amounts of medicine in batches. Compared with existing common syringes, the biggest difference is that it can achieve equal amount injection in batches without the need for professional medical staff to control the injection volume. Therefore, quantitative injection devices are mostly used in scenarios where patients need to inject themselves, such as osteoporosis patients injecting themselves with teripasculoskeletal injection.

On the other hand, for the structure and functional characteristics of the quantitative injection device, it needs to do at least the following:

1. After a single injection, the push rod is fixed and can neither push the drug forward nor return to a vague position;

2. The distance the push rod moves forward each time is fixed;

3. The forward moving structure of the push rod must ensure that it can be used multiple times. For example, if 1/5 of the drug dose is injected each time, the forward moving structure must ensure that it can be accurately and repeatedly pushed at least 5 times.

For example, a Chinese utility model patent with patent announcement number CN216169226U and announcement date 2022.04.05 discloses a one-way propulsion type anti-reusable micro-volume and quantitative syringe, the structure of which includes an empty barrel, a rubber plug arranged at the top end of the core rod in the empty barrel, an outer sleeve arranged in the opening direction of the empty barrel, and a quantitative propulsion structure arranged in the outer sleeve, and quantitative injection is achieved through the propulsion structure.

The quantitative syringe in the utility model patent achieves the above-mentioned effect of "the push rod does not move after the injection operation" mainly by: pushing the card to clamp the core rod;

The method for achieving the above-mentioned effect of "the push rod moving forward at a constant distance" is mainly as follows: the push clamp and the clamp can be periodically stuck;

The method for achieving the above-mentioned "pushing rod moving forward multiple times" effect is mainly as follows: pressing the hand can release the clamping action of the pushing card on the core rod, so that the core rod can move forward again.

However, the biggest defect of the quantitative syringe in actual use, which is also the technical problem to be solved by the present invention, is:

After the core rod completes an injection operation, the type of force that fixes it is friction. Friction itself has a relatively high instability characteristic and cannot guarantee that the core rod has a higher precision forward and backward immobilization effect.

The structural and functional characteristics are ultimately reflected in the amount of medicine injected in a single quantitative injection, that is, it is difficult to ensure that the amount of medicine each time is equal with high precision.

Therefore, in summary, there is an urgent need for a new quantitative injection device with a more stable and clear endpoint indication state for quantitative injection operations, so that the difference between the amount of medicine injected each time can be as small as possible.

Summary of the invention

The present invention provides a quantitative injection device, which can be provided with a fixed ratchet, a ratchet-tube combination unit, a slotted screw unit, a movable ratchet unit, and a rotating ratchet unit on a housing unit, so that: 1. Each rotation of the rotating ratchet unit is at a fixed angle, which drives the ratchet-tube combination unit to rotate at a fixed angle, thereby making the distance of the slotted screw unit moving forward each time fixed, and finally achieving the purpose of quantitative injection; 2. After one injection operation, the reverse rotation reset angle of the rotating ratchet unit is also fixed, and will not drive the ratchet-tube combination unit to rotate reversely, thereby ensuring that the slotted screw unit is completely fixed during the injection operation; 3. Each time the rotating ratchet unit rotates forward first and then reversely, it is a complete one-time injection operation, which can be repeated completely independently for multiple times until the medicine in the cartridge bottle is injected in batches; 4. A single quantitative injection device corresponds to a single cartridge bottle and multiple needles, thereby ensuring multiple injection operations within a relatively long period of time and the effect of overall single use.

The technical solution adopted by the present invention to solve the above-mentioned problem is: a quantitative injection device, which structure includes a shell unit, a fixed ratchet arranged in the shell unit, a ratchet-tube combination unit inserted in the shell unit and connected to the fixed ratchet, a slotted screw unit screwed on the shell unit and engaged with the ratchet-tube combination unit and used to push the drug, a movable ratchet unit engaged in the ratchet-tube combination unit and used to rotationally drive the ratchet-tube combination unit, and a rotating ratchet unit arranged in the shell unit and used to drive the movable ratchet unit.

A further preferred technical solution is that the outer shell unit includes a tube body, an end plate arranged on the tube body and having the fixed ratchet on the inner side surface, an internal threaded hole arranged on the end plate and used to install the slotted screw unit, and an angle limit block arranged on the inner annular surface of the tube body and used to block the engagement of the rotating ratchet unit.

A further preferred technical solution is that the housing unit further comprises an opening arranged on the tube body, and an anti-dropping buckle plate arranged on the opening and used for engaging the ratchet-tube combination unit.

A further preferred technical solution is that the pawl-tube combination unit includes an intermediate ring arranged on the anti-drop buckle plate, an arc-shaped pawl arranged on the intermediate ring and connected to the fixed ratchet, a rear end tube arranged on the intermediate ring and used for inserting and installing the movable ratchet unit, a drive block arranged on the inner ring surface of the intermediate ring and used for engaging the slotted screw unit, and a drive groove arranged on the inner ring surface of the rear end tube and used for engaging the movable ratchet unit.

A further preferred technical solution is that the pawl-tube combination unit also includes a fixing opening provided on the rear end tube and used for inserting the rotating pawl unit.

A further preferred technical solution is that the slotted screw unit includes a threaded rod arranged on the internal threaded hole, plugged into the pawl-tube combination unit, the movable ratchet unit and the rotating pawl unit, and used to push the cartridge bottle, and a lengthwise slot arranged on the threaded rod and used to insert the drive block.

A further preferred technical solution is that the movable ratchet unit includes a support spring arranged on the intermediate ring and used to allow the rotating pawl unit to rotate idly, a slotted ratchet arranged on the support spring, and a protruding block arranged on the slotted ratchet and engaging the driving groove.

A further preferred technical solution is that the rotating pawl unit includes a rotating tube arranged in the tube body, a protruding pawl arranged on the end surface of the rotating tube and used to engage the slotted ratchet, and a fan-shaped protruding block arranged on the outer annular surface of the rotating tube and used to engage the angle limit block.

A further preferred technical solution is that the rotating pawl unit further includes a connecting ring which is arranged on the outer annular surface of the rotating tube and is used for inserting into the fixing port.

A further preferred technical solution is that: a sliding tube unit for driving the rotating pawl unit is further provided in the tube body.

A further preferred technical solution is that: the sliding tube unit comprises a round tube arranged between the tube body and the rotating tube, a protruding thread arranged on the inner annular surface of the round tube, and a lengthwise protruding strip arranged on the outer annular surface of the round tube;

The housing unit further comprises a slide groove disposed on the annular surface of the tube body and used for engaging the length-direction protruding strip;

The rotating pawl unit further includes a thread groove which is arranged on the outer annular surface of the rotating tube and is used for connecting with the protruding thread.

A further preferred technical solution is that: an outer tube unit for inserting and installing a cartridge bottle and connecting and installing a needle is also sleeved on the tube body.

A further preferred technical solution is that: the outer tube unit comprises a front end tube, a needle mounting tube arranged on the front end tube, and a rear opening arranged on the front end tube and used for engaging the tube body;

The housing unit also includes a clamping block which is arranged on the outer annular surface of the tube body and is used for clamping into the rear opening.

A further preferred technical solution is that the outer tube unit further comprises a front opening arranged on the front end tube, and a buckle unit for clamping the cartridge bottle is provided on the front opening.

A further preferred technical solution is that the buckle unit includes a circular ring body arranged in the front end tube, an outer buckle arranged on the circular ring body and used to engage the front opening, and an inner buckle arranged on the circular ring body and used to clamp the cartridge bottle.

A further preferred technical solution is that the buckle unit also includes an arc-shaped strip with both ends arranged on the annular body and used to receive the pressing effect of the end plate.

A further preferred technical solution is that: the arc-shaped strip protrudes toward the radial outer side of the annular body;

The outer tube unit also includes an installation positioning groove arranged on the inner annular surface of the front end tube and used for clamping the arc strip.

A further preferred technical solution is that the housing unit further comprises a rectangular opening provided on the end plate and used for engaging the arc strip.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of the present invention.

FIG. 2 is a schematic diagram showing the position of the slotted screw unit in the present invention.

FIG. 3 is an exploded view of the pawl-tube combination unit of the present invention.

FIG. 4 is an exploded view of the movable ratchet unit in the present invention.

FIG. 5 is a schematic structural diagram of a rotary pawl unit in the present invention.

FIG. 6 is a schematic diagram showing the matching relationship between the pawl-tube combination unit and the rotating pawl unit in the present invention.

FIG. 7 is a schematic structural diagram of the housing unit in the present invention.

FIG. 8 is a schematic diagram showing the position of the rectangular opening in the present invention.

FIG. 9 is a schematic diagram showing the position and shape of the driving block in the present invention.

FIG. 10 is a schematic structural diagram of the slotted screw unit in the present invention.

FIG. 11 is a schematic diagram showing the position and shape of the annular protruding block and the connecting ring in the present invention.

FIG. 12 is a schematic structural diagram of the sliding pipe unit in the present invention.

FIG. 13 is a schematic diagram of the structure of the outer tube unit in the present invention.

FIG. 14 is a schematic diagram showing the position and shape of the installation positioning groove in the present invention.

FIG. 15 is a schematic diagram showing the use of the buckle unit in the present invention.

In the figure, the meanings of the symbols are as follows:

Cartridge bottle a;

Housing unit 1, fixed ratchet 2, pawl-tube combination unit 3, slotted screw unit 4, movable ratchet unit 5, rotating pawl unit 6;

Tube body 101, end plate 102, internal threaded hole 103, angle limit block 104, opening 105, anti-drop plate 106, slide groove 107, clamping block 108, rectangular opening 109;

The middle ring 301, the arc-shaped ratchet 302, the rear end tube 303, the driving block 304, the driving groove 305, and the fixing port 306;

Threaded rod 401, slotted in length direction 402;

Support spring 501, slotted ratchet 502, protruding block 503;

Rotating tube 601, protruding pawl 602, fan-shaped protruding block 603, connecting ring 604, thread groove 605;

Sliding tube unit 7, outer tube unit 8, buckle unit 9;

Round tube 701, protruding thread 702, and protruding strip 703 in length direction;

Pen tip tube 801, needle mounting tube 802, rear opening 803, front opening 804, mounting positioning groove 805;

Ring body 901, outer buckle 902, inner buckle 903, arc strip 904;

Pen cap 10.

Detailed ways

The following descriptions are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention.

As shown in Figures 1-15, the quantitative injection device comprises a housing unit 1, a fixed ratchet 2 arranged in the housing unit 1, a ratchet-tube combination unit 3 inserted in the housing unit 1 and connected to the fixed ratchet 2, a slotted screw unit 4 threadedly arranged on the housing unit 1 and engaged with the ratchet-tube combination unit 3 and used to push the drug, a movable ratchet unit 5 engaged in the ratchet-tube combination unit 3 and used to rotationally drive the ratchet-tube combination unit 3, and a rotating ratchet unit 6 arranged in the housing unit 1 and used to drive the movable ratchet unit 5.

In this embodiment, when the quantitative injection device is initially used, the slotted screw unit 4 is simultaneously threadedly connected to the housing unit 1 and clamped to the pawl-tube combination unit 3, so that the rotational movement of the pawl-tube combination unit 3 can be converted into the forward movement of the slotted screw unit 4.

In addition, the fixed ratchet 2 and the pawl-tube combination unit 3 are a pair of ratchet mechanisms, and the movable ratchet unit 5 and the rotating pawl unit 6 are another pair of ratchet mechanisms. Between the two pairs of ratchet mechanisms, the movable ratchet unit 5 drives the pawl-tube combination unit 3, so the initial rotational motion of the rotating pawl unit 6 can be converted step by step into the forward motion of the slotted screw unit 4.

What is more critical is that when the rotating pawl unit 6 is reversely rotated and reset, it cannot reversely rotate together with the movable ratchet unit 5, which is reflected in the slotted screw unit 4, that is, it will not retreat, which is very important for quantitative injection operation.

Of course, it is necessary to additionally explain that a complete quantitative injection device product also needs to include a suitable "front end cavity", which is used to load the cartridge bottle a and is connected to the housing unit 1, and finally ensures that the slotted screw unit 4 can smoothly push the cartridge bottle a. In this case, the "front end cavity" can be a partial structure of an existing quantitative injection device.

The housing unit 1 includes a tube body 101, an end plate 102 arranged on the tube body 101 and having the fixed ratchet 2 on the inner side surface, an internal threaded hole 103 arranged on the end plate 102 and used to install the slotted screw unit 4, and an angle limit block 104 arranged on the inner annular surface of the tube body 101 and used to block the engagement of the rotating pawl unit 6.

In this embodiment, the single rotation angle of the rotating pawl unit 6 is proportional to the single forward distance of the slotted screw unit 4. Therefore, the effect of quantitative injection requires that the rotating pawl unit 6 has a rotation angle limiting function, that is, a single complete rotation of the rotating pawl unit 6 is difficult to go over the angle limit block 104. In other words, this is the purpose of setting the angle limit block 104.

In addition, the inner annular surface of the fixed ratchet 2 is aligned with the internal threaded hole 103, so the internal thread on the internal threaded hole 103 can appropriately extend into the fixed ratchet 2, ensuring that the screw connection between the housing unit 1 and the slotted screw unit 4 is more stable.

The housing unit 1 further includes an opening 105 disposed on the tube body 101 , and an anti-drop plate 106 disposed on the opening 105 and used for engaging the ratchet-tube combination unit 3 .

In this embodiment, the pawl-tube combination unit 3 can only rotate in the tube body 101 and cannot move left and right, otherwise it will accidentally push or pull the slotted screw unit 4, so this is the role of the anti-drop buckle plate 106.

The general shape of the anti-drop buckle plate 106 is an "L-shape", and the short side of the "L-shape" protrudes inward appropriately to ensure that the pawl-tube combination unit 3 is difficult to retreat outward after installation.

The pawl-tube combination unit 3 includes an intermediate ring 301 arranged on the anti-drop buckle plate 106, an arc-shaped pawl 302 arranged on the intermediate ring 301 and connected to the fixed ratchet 2, a rear end tube 303 arranged on the intermediate ring 301 and used for inserting and installing the movable ratchet unit 5, a driving block 304 arranged on the inner annular surface of the intermediate ring 301 and used for engaging the slotted screw unit 4, and a driving groove 305 arranged on the inner annular surface of the rear end tube 303 and used for engaging the movable ratchet unit 5.

In this embodiment, the arc-shaped pawl 302 and the fixed ratchet 2 form a ratchet mechanism commonly used in the prior art, ensuring that the pawl-tube combination unit 3 can only rotate forward, and "forward rotation" refers to driving the slotted screw unit 4 forward.

It should also be noted that: 1. The end point of the insertion and installation action of the intermediate ring 301 is to abut against the fixed ratchet 2; 2. At the same time, the end point of the insertion and installation action of the arc pawl 302 is to abut against the end plate 102, so as to improve the front and rear position stability of the rotation action of the pawl-tube combination unit 3.

In addition, a circle of protrusions is provided on the non-installation end surface of the fixed ratchet 2, and the cross-sectional shape of the protrusions is arc-shaped. The direct effect of the protrusions is to reduce the contact area between the fixed ratchet 2 and the intermediate ring 301, and the ultimate effect is to reduce the friction resistance of the rotation action of the ratchet-tube combination unit 3.

The pawl-tube combination unit 3 further includes a fixing opening 306 disposed on the rear end tube 303 and used for inserting the rotating pawl unit 6 .

In this embodiment, the rotating pawl unit 6 is the same as the pawl-tube combination unit 3 , which can only rotate but cannot move left or right. Therefore, the fixing opening 306 is provided to indirectly fix the rotating pawl unit 6 left or right on the tube body 101 .

The slotted screw unit 4 includes a threaded rod 401 which is arranged on the internal threaded hole 103 and is plugged into the pawl-tube combination unit 3, the movable ratchet unit 5 and the rotating pawl unit 6 and is used to push the cartridge bottle a, and a lengthwise slot 402 which is arranged on the threaded rod 401 and is used to insert the driving block 304.

In this embodiment, a circular enlargement block is further provided at the front end of the threaded rod 401, and the enlargement block is closely attached to the inner wall of the cartridge bottle a, so as to ensure that the pushing action of the rubber stopper in the cartridge bottle a is more uniform and stable.

The movable ratchet unit 5 includes a support spring 501 disposed on the intermediate ring 301 and used to allow the rotating pawl unit 6 to rotate idly, a slotted ratchet 502 disposed on the support spring 501 , and a protruding block 503 disposed on the slotted ratchet 502 and engaging with the driving slot 305 .

In this embodiment, the shape of the slot on the slotted ratchet 502 is a commonly used right triangle. In other words, the shape of the pawl on the rotating pawl unit 6 is also a right triangle, ensuring that the latter can effectively drive the former in one direction.

In addition, the protruding block 503 is always inserted into the driving groove 305 and slides relatively on the driving groove 305. When the protruding block 503 slides relatively, the rotating pawl unit 6 rotates in the opposite direction. At this time, a complete quantitative injection operation is completed, and the rotating pawl unit 6 rotates outward to reset.

Therefore, the support spring 501 is the key to allow the rotating pawl unit 6 to reversely rotate and reset. At this time, the rotating pawl unit 6 has a certain damping, or "feel" when it reverses, and the resistance comes from the compression of the support spring 501.

The rotating pawl unit 6 includes a rotating tube 601 arranged in the tube body 101, a protruding pawl 602 arranged on the end surface of the rotating tube 601 and used to engage the slotted ratchet 502, and a fan-shaped protruding block 603 arranged on the outer annular surface of the rotating tube 601 and used to engage the angle limit block 104.

In this embodiment, the protruding pawl 602 is the above-mentioned right-angled triangle block, and the fan-shaped protruding block 603 rotates back and forth between two adjacent angle limit blocks 104 and cannot cross the angle limit blocks 104.

Specifically, when the fan-shaped protruding block 603 abuts against one of the angle limit blocks 104 at the rear end in the rotation direction, the protruding pawl 602 is stuck on one of the slots of the slotted ratchet 502, and the last injection operation is completed.

Next, the fan-shaped protrusion 603 rotates and moves from the rear end of the angle limit block 104 to the front end of the angle limit block 104, which is the process in which the protruding pawl 602 rotates the slotted ratchet 502 together with the complete angle of the injection operation.

Finally, the fan-shaped protruding block 603 rotates in the opposite direction and returns to the initial state of pressing against the angle limit block 104 at the rear end, and the protruding pawl 602 passes over the upper surface of the slotted ratchet 502 and comes to the slotted position of the previous slotted ratchet 502.

Therefore, a complete quantitative injection operation is an action in which the protruding pawl 602 drives between two adjacent slots on the slotted ratchet wheel 502 and then retracts.

The rotating pawl unit 6 further includes a connecting ring 604 which is arranged on the outer annular surface of the rotating tube 601 and is used for inserting into the fixing port 306 .

In this embodiment, the fixing opening 306 includes an opening edge portion protruding inwardly, so as to ensure that the connecting ring 604 is always stuck on the fixing opening 306 even when rotating, and to ensure that the rotating pawl unit 6 does not fall outward.

Of course, the fan-shaped annular protruding block 603 always presses the end surface of the rear end tube 303, and the rotating pawl unit 6 will not shift inwards.

The tube body 101 is further provided with a sliding tube unit 7 for driving the rotating pawl unit 6 .

In this embodiment, the function of the sliding tube unit 7 is to convert the initial action of the injection operation: the rotation of the rotating pawl unit 6, into an inward pushing action of the sliding tube unit 7. This method is relatively simpler and more convenient.

The sliding tube unit 7 includes a circular tube 701 arranged between the tube body 101 and the rotating tube 601, a protruding thread 702 arranged on the inner annular surface of the circular tube 701, and a length-protruding strip 703 arranged on the outer annular surface of the circular tube 701; the outer shell unit 1 also includes a sliding groove 107 arranged on the inner annular surface of the tube body 101 and used to engage the length-protruding strip 703; the rotating pawl unit 6 also includes a thread groove 605 arranged on the outer annular surface of the rotating tube 601 and used to connect the protruding thread 702.

In this embodiment, the end point of the inward push of the circular tube 701 may be that the inner end surface of the slide groove 107 abuts against the length-protruding strip 703 , or that the arc-shaped pawl 302 completes a complete single rotation action on the fixed ratchet 2 .

The end point of the circular tube 701 withdrawing outward is that the protruding pawl 602 brought with it retreats to the next slotted position on the slotted ratchet 502 .

In addition, the inner annular surface of the tube body 101 may be provided with a left and right limit structure for the length-direction protruding strip 703 to ensure that the pushing-in and withdrawing actions of the circular tube 701 have a clear end position.

The tube body 101 is also sleeved with an outer tube unit 8 for inserting and installing the cartridge bottle a and connecting and installing a needle.

In this embodiment, a protruding block for engaging the pen cap 10 is further provided on the outer ring surface of the outer tube unit 8 .

The outer tube unit 8 includes a nib tube 801, a needle mounting tube 802 arranged on the nib tube 801, and a rear opening 803 arranged on the nib tube 801 and used to engage with the tube body 101; the outer shell unit 1 also includes a block 108 arranged on the outer annular surface of the tube body 101 and used to engage with the rear opening 803.

In this embodiment, the needle mounting tube 802 is an externally threaded tube, and the pen tip tube 801 is also provided with an opening for observing the liquid level of the cartridge bottle a.

The outer tube unit 8 further comprises a front opening 804 arranged on the nib tube 801 , and a buckle unit 9 for clamping the cartridge bottle a is provided on the front opening 804 .

In this embodiment, the front end of the cartridge bottle a is supported by the needle mounting tube 802, and the rear end is clamped by the buckle unit 9, so as to ensure that the cartridge bottle a itself is fixed, which is also the basis for the precision of the quantitative injection operation.

The buckle unit 9 includes a circular body 901 disposed in the pen tip tube 801, an outer buckle 902 disposed on the circular body 901 and used to engage the front opening 804, and an inner buckle 903 disposed on the circular body 901 and used to clamp the cartridge bottle a.

In this embodiment, the rear opening 803 can be used as a transitional position when the buckle unit 9 is installed, so the front opening 804 and the rear opening 803 are circumferentially aligned.

In addition, the outer buckle 902 and the inner buckle 903 are both generally in an "L-shape", and when the outer buckle 902 is inserted into the front opening 804, the inner buckle 903 clamps the rear end of the cartridge bottle a.

The buckle unit 9 further includes an arc-shaped strip 904 , both ends of which are arranged on the annular body 901 and are used to receive the pressing effect of the end plate 102 .

In this embodiment, the first function of the arc strip 904 is to allow the housing unit 1 to assist in clamping the cartridge bottle a, because it may be difficult to ensure sufficient fixing strength at the outer buckle 902 .

The arc strip 904 protrudes radially outward from the annular body 901 ; the outer tube unit 8 also includes an installation positioning groove 805 arranged on the inner annular surface of the pen tip tube 801 and used for engaging the arc strip 904 .

In this embodiment, after the arc strip 904 protrudes radially outward from the annular body 901, it has a second function, that is, when the arc strip 904 is installed, it is stuck and docked with the installation positioning groove 805, which can ensure that the outer buckle 902 is always located on the straight path determined by the rear opening 803 and the front opening 804, avoiding the problem of the outer buckle 902 being unable to engage.

The housing unit 1 further includes a rectangular opening 109 disposed on the end plate 102 and used for engaging the arc strip 904 .

In this embodiment, if the rectangular opening 109 is not opened, the end plate 102 can only support the middle highest point of the arc strip 904. At this time, the auxiliary clamping force of the shell unit 1 on the arc strip 904 is to press and deform the arc strip 904 instead of driving the entire buckle unit 9, which needs to be avoided.

After the rectangular opening 109 is introduced, the edges at both ends of the rectangular opening 109 can directly squeeze the "root" of the arc strip 904, so that the auxiliary clamping force of the shell unit 1 squeezes and fixes the buckle unit 9 as much as possible, and finally further reinforces the cartridge bottle a.

At the same time, this also makes the positioning effect and the circumferential non-missing characteristics between the arc strip 904 and the installation positioning groove 805 more important, otherwise the arc strip 904 is difficult to be partially inserted into the rectangular opening 109.

The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various modifications can be made within the knowledge of ordinary technicians in the technical field without departing from the purpose of the present invention. These are all non-creative modifications and are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims (10)

1. A quantitative injection device, characterized in that: the structure comprises a housing unit (1), a fixed ratchet (2) arranged in the housing unit (1), a ratchet-tube combination unit (3) inserted in the housing unit (1) and connected to the fixed ratchet (2), a slotted screw unit (4) screwed on the housing unit (1) and engaged with the ratchet-tube combination unit (3) and used to push the medicine, a movable ratchet unit (5) engaged in the ratchet-tube combination unit (3) and used to rotationally drive the ratchet-tube combination unit (3), and a rotating ratchet unit (6) arranged in the housing unit (1) and used to drive the movable ratchet unit (5), The housing unit (1) comprises a tube body (101), an end plate (102) disposed on the tube body (101) and having an inner side surface provided with the fixed ratchet (2), an internal threaded hole (103) disposed on the end plate (102) and used for mounting the slotted screw unit (4), and an angle stopper (104) disposed on the inner annular surface of the tube body (101) and used for blocking and engaging the rotating ratchet unit (6). The housing unit (1) further comprises an opening (105) arranged on the tube body (101), and an anti-dropping buckle plate (106) arranged on the opening (105) and used for engaging the ratchet-tube combination unit (3). The pawl-tube combination unit (3) comprises an intermediate circular ring (301) arranged on the anti-drop buckle plate (106), an arc-shaped pawl (302) arranged on the intermediate circular ring (301) and connected to the fixed ratchet (2), a rear end tube (303) arranged on the intermediate circular ring (301) and used for inserting and installing the movable ratchet unit (5), a driving block (304) arranged on the inner annular surface of the intermediate circular ring (301) and used for engaging the slotted screw unit (4), and a driving groove (305) arranged on the inner annular surface of the rear end tube (303) and used for engaging the movable ratchet unit (5). The ratchet-tube combination unit (3) further comprises a fixing opening (306) provided on the rear end tube (303) and used for inserting the rotating ratchet unit (6). The slotted screw unit (4) comprises a threaded rod (401) disposed on the internal threaded hole (103), plugged into the pawl-tube combination unit (3), the movable ratchet unit (5) and the rotating pawl unit (6) and used to push the cartridge bottle (a), and a lengthwise slot (402) disposed on the threaded rod (401) and used to insert the drive block (304). The movable ratchet unit (5) comprises a support spring (501) arranged on the intermediate ring (301) and used to allow the rotating pawl unit (6) to rotate idly, a slotted ratchet (502) arranged on the support spring (501), and a protruding block (503) arranged on the slotted ratchet (502) and engaging with the driving groove (305). The rotating pawl unit (6) comprises a rotating tube (601) arranged in the tube body (101), a protruding pawl (602) arranged on the end surface of the rotating tube (601) and used to engage with the slotted ratchet (502), and a fan-shaped protruding block (603) arranged on the outer annular surface of the rotating tube (601) and used to engage with the angle limiting block (104). The rotating pawl unit (6) further comprises a connecting ring (604) which is arranged on the outer annular surface of the rotating tube (601) and is used for being inserted into the fixing port (306). 2. The quantitative injection device according to claim 1, characterized in that: a sliding tube unit (7) for driving the rotating pawl unit (6) is further provided in the tube body (101). 3. The quantitative injection device according to claim 2, characterized in that: the sliding tube unit (7) comprises a round tube (701) arranged between the tube body (101) and the rotating tube (601), a protruding thread (702) arranged on the inner annular surface of the round tube (701), and a lengthwise protruding strip (703) arranged on the outer annular surface of the round tube (701); The housing unit (1) further comprises a sliding groove (107) arranged on the inner annular surface of the tube body (101) and used for engaging the lengthwise protruding strip (703); The rotating pawl unit (6) further comprises a thread groove (605) which is arranged on the outer annular surface of the rotating tube (601) and is used to connect to the protruding thread (702). 4. The quantitative injection device according to claim 2, characterized in that: the tube body (101) is also sleeved with an outer tube unit (8) for inserting and installing the cartridge bottle (a) and connecting and installing the needle. 5. The quantitative injection device according to claim 4, characterized in that: the outer tube unit (8) comprises a pen tip tube (801), a needle mounting tube (802) arranged on the pen tip tube (801), and a rear opening (803) arranged on the pen tip tube (801) and used for engaging the tube body (101); The housing unit (1) further comprises a clamping block (108) arranged on the outer annular surface of the tube body (101) and used for clamping into the rear opening (803). 6. The quantitative injection device according to claim 5, characterized in that: the outer tube unit (8) further comprises a front opening (804) arranged on the pen tip tube (801), and the front opening (804) is provided with a buckle unit (9) for clamping the cartridge bottle (a). 7. The quantitative injection device according to claim 6, characterized in that the buckle unit (9) comprises a circular body (901) arranged in the pen tip tube (801), an outer buckle (902) arranged on the circular body (901) and used to engage the front opening (804), and an inner buckle (903) arranged on the circular body (901) and used to clamp the cartridge bottle (a). 8. The quantitative injection device according to claim 7, characterized in that: the buckle unit (9) further comprises an arc-shaped strip (904) with both ends arranged on the annular body (901) and used to receive the pressing effect of the end plate (102). 9. The quantitative injection device according to claim 8, characterized in that: the arc-shaped strip (904) protrudes toward the radial outer side of the annular body (901); The outer tube unit (8) further comprises a mounting positioning groove (805) arranged on the inner annular surface of the pen tip tube (801) and used for engaging the arc-shaped strip (904). 10. The quantitative injection device according to claim 8, characterized in that the housing unit (1) further comprises a rectangular opening (109) provided on the end plate (102) and used for engaging the arc strip (904).