A disposable injection pen with precise dose adjustment

Abstract

This specification provides a disposable injection pen with precisely adjustable dosage, including a cartridge holder, a pen body tube, a piston, a screw, a positioner, a transmission rod, a guide sleeve, a transmission connecting rod, a locking ring, a dosage cylinder, and a button. The cartridge holder has a cavity for holding the medication. The positioner is fixedly mounted at the connection between the cartridge holder and the pen body tube. The piston is located at one end of the screw, and the other end of the screw passes through the positioner and extends into the transmission rod. One end of the transmission rod is rotatably connected to the positioner, and the other end is axially movable and extends into the cavity. The transmission link is described above; the locking ring is disposed inside the dose rotating cylinder, the transmission link passes through the locking ring and extends into the dose rotating cylinder, the dose rotating cylinder rotatably passes through the guide sleeve and extends into the pen body tube, the guide sleeve is disposed inside the pen body tube and connected to the dose rotating cylinder; a button spring is provided at the tail end of the dose rotating cylinder, one end of the button extends into the dose rotating cylinder and is connected to the transmission link through the button spring. This utility model has low operation difficulty for patients, good user experience, simple product structure, and is easy to design and manufacture.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, and in particular to a disposable injection pen with precisely adjustable dosage. Background Technology

[0002] Injection pens are a common type of drug delivery device. With their advantages of precise dosage, ease of use, and high safety, they have become a popular choice for home self-injection by patients. They are particularly widely used in insulin delivery. In terms of specific categories, injection pens can be divided into disposable non-adjustable injection pens, reusable adjustable injection pens, and disposable or single-use adjustable injection pens. Due to the large number of diabetic patients requiring insulin injections, and the need for 1-4 injections daily (depending on disease progression), there is a very high demand for pen injectors, including reusable and disposable adjustable injection pens. Reusable insulin injection pens are low-cost and environmentally friendly. Single-use adjustable insulin injection pens, on the other hand, have a significant market potential due to their portability, ease of use, and hygiene.

[0003] Most disposable adjustable-dose injection pens on the market today consist of a cartridge, a graduated dose adjustment device, and a rotatable dose button, allowing patients to adjust the injection dosage themselves. Since these injection devices are for a single injection, and the pens are typically complex in structure, have numerous parts, and are difficult to manufacture, and because they are primarily designed for diabetic patients with poor vision, additional dose indication methods are usually required besides the graduated markings.

[0004] Therefore, how to provide an injection pen that is simple in structure, easy to manufacture, and can provide a prompting effect when patients adjust the dosage is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0005] The purpose of this specification is to provide a disposable injection pen with precisely adjustable dosage. The device has a simple structure, is easy to manufacture, and has an audible prompt function.

[0006] This specification provides a disposable injection pen with precisely adjustable dosage, including a cartridge holder, a pen body tube, a piston, a screw, a positioner, a transmission rod, a guide sleeve, a transmission connecting rod, a locking ring, a dosage cylinder, and a button. The cartridge holder has a cavity for holding the medication, and the positioner is fixedly mounted at the connection between the cartridge holder and the pen body tube. The screw has an external thread on its outer wall, and the positioner has an internal thread on its inner wall that mates with the external thread of the screw. The piston is located at one end of the screw, and the other end of the screw extends through the positioner into... Inside the transmission rod; one end of the transmission rod is rotatably connected to the positioner, and the other end extends axially into the transmission connecting rod; the locking ring is disposed inside the dosage drum, the transmission connecting rod passes through the locking ring and extends into the dosage drum, the dosage drum rotatably passes through the guide sleeve and extends into the pen body tube, the guide sleeve is disposed inside the pen body tube and at the connection point with the dosage drum; a button spring is disposed at the tail end of the dosage drum, one end of the button extends into the dosage drum and is connected to the end of the transmission connecting rod through the button spring.

[0007] Preferably, the outer wall of the transmission rod is provided with at least one axial groove, and the inner wall of the transmission connecting rod is provided with a boss that cooperates with the axial groove.

[0008] Preferably, the outer wall of the transmission connecting rod is provided with an external thread, and the inner wall of the locking ring is provided with a locking key and a convex key that mates with the external thread of the transmission connecting rod.

[0009] Preferably, the outer wall of the dose rotating cylinder is provided with an external thread, and the inner wall of the guide sleeve is provided with a guide sleeve thread that mates with the external thread of the dose rotating cylinder.

[0010] Preferably, the pen body tube has a viewing window, and the guide sleeve is fixedly connected to the viewing window of the pen body tube, and the guide sleeve has a guide sleeve viewing window.

[0011] Preferably, the dosing cylinder has multiple settings, each setting of the dosing cylinder corresponds to each unit of the drug dosage in the pen refill holder, and the total number of settings of the dosing cylinder is equal to the total number of drug dosage units.

[0012] Preferably, the locator has two elastic buckles along its axial direction, and the end of the pen refill holder has two tile-shaped elastic buckles, with the two elastic buckles located between the two elastic buckles of the locator, so that the two tile-shaped elastic buckles and the two elastic buckles form a ring.

[0013] Preferably, the end of the transmission rod is provided with an elastic ratchet, and the inner side of the positioner is provided with a plurality of ratchet teeth in the circumferential or axial direction, which cooperate with the elastic ratchet.

[0014] Preferably, the end of the pen refill holder is provided with an external thread for connection to the injection needle.

[0015] Preferably, the disposable injection pen with precisely adjustable dosage includes a pen cap, which is detachably fitted over the refill holder.

[0016] This specification provides a disposable injection pen with precisely adjustable dosage. By incorporating a button spring at the tail end, it provides button damping, optimizing patient comfort during injection. Furthermore, the pen emits an audible alert when the patient rotates the dosage cylinder to adjust the injection volume, thus reminding the patient to adjust the dosage and enhancing the user experience. In addition, the device provided by this technical solution has a simple structure, is easy to process and assemble, and has low production costs. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an exploded view of the embodiments described in this specification;

[0019] Figure 2 This is a schematic diagram illustrating the implementation of the embodiments described in this specification;

[0020] Figure 3 This is a cross-sectional view of an embodiment of this specification;

[0021] Figure 4 This is a schematic diagram of the preferred embodiment 1 of the transmission rod in the embodiments of this specification;

[0022] Figure 5 This is a schematic diagram of the preferred embodiment 2 of the transmission rod in the embodiments of this specification;

[0023] Among them, 1-pen refill holder, 101-tile-shaped elastic retainer, 2-pen body tube, 21-pen body tube window, 3-piston, 4-screw, 5-positioner, 51-elastic retainer, 6-drive rod, 61-elastic ratchet, 7-guide sleeve, 71-guide sleeve window, 8-drive linkage, 9-locking ring, 10-dosage drum, 11-button, 12-button spring. Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments in this specification, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0025] like Figure 1-3 As shown in the figure, this specification provides a disposable injection pen with precisely adjustable dosage, including a pen cartridge holder 1, a pen body tube 2, a piston 3, a screw 4, a positioner 5, a transmission rod 6, a guide sleeve 7, a transmission connecting rod 8, a locking ring 9, a dosage cylinder 10, and a button 11. The pen cartridge holder 1 is provided with a cavity for placing the medicine. The positioner 5 is fixedly connected to the connection between the pen cartridge holder 1 and the pen body tube 2. The outer wall of the screw 4 is provided with an external thread, and the inner wall of the positioner 5 is provided with an internal thread that mates with the external thread of the screw 4. The positioner 5 is sleeved on the screw 4. Piston 3 is located at the end of screw 4 near the pen refill holder 1. The end of screw 4 away from pen refill holder 1 passes through positioner 5 and extends into the transmission rod 6. Screw 4 can move axially relative to transmission rod 6 but cannot rotate. One end of transmission rod 6 is rotatably connected to positioner 5, and the other end can move axially and extend into transmission link 8. Locking ring 9 is rotatably sleeved on the outside of transmission link 8 and located inside dosage cylinder 10. Transmission link 8 passes through locking ring 9 and extends into dosage cylinder 10. Guide sleeve 7 is fixedly located inside pen body tube 2 at the connection with dosage cylinder 10. Dosage cylinder 10 can rotatably pass through guide sleeve 7 and extend into pen body tube 2. A button spring 12 is provided at the tail end of dosage cylinder 10. One end of button 11 extends into dosage cylinder 10 and is connected to the end of transmission link 8 through button spring 12.

[0026] The outer wall of the transmission rod 6 has at least one axial groove, and the inner wall of the transmission connecting rod 8 is provided with a boss that mates with the axial groove.

[0027] The outer wall of the transmission link 8 is provided with an external thread, and the inner wall of the locking ring 9 is provided with a locking key and a protruding key that mates with the external thread of the transmission link 8. The transmission link 8 can rotate and move axially inside the locking ring 9 through the external thread. The locking ring 9 restricts the axial displacement of the transmission link 8 through the locking key, so that the transmission link 8 does not disengage from the locking ring 9.

[0028] The outer wall of the dosing cylinder 10 is provided with external threads, and the inner wall of the guide sleeve 7 is provided with guide sleeve threads that mate with the external threads of the dosing cylinder 10. The pen body tube 2 has a viewing window 21, and the guide sleeve 7 has a guide sleeve viewing window 71 and is fixedly connected to the pen body tube viewing window 21. The dosing cylinder 10 has multiple positions, each position of the dosing cylinder 10 corresponds to each unit of the drug dosage in the pen refill holder 1, and the total number of positions of the dosing cylinder 10 is equal to the total number of drug dosage units.

[0029] The locator 5 is provided with two elastic buckle feet 51 along the axis, and the corresponding pen refill holder 1 is provided with two tile-shaped elastic buckle feet 101 at its end. The two elastic buckle feet 101 are respectively located between the two elastic buckle feet 51 of the locator, so that the two tile-shaped elastic buckle feet 101 and the two elastic buckle feet 51 form a ring.

[0030] The end of the pen refill holder 1 furthest from the pen body tube 2 is provided with an external thread for connection to an external injection needle. It also includes a pen cap 13, which is detachably fitted onto the outside of the pen refill holder 1.

[0031] Specifically, such as Figure 4-5 As shown, the end of the transmission rod 6 is provided with an elastic ratchet 61, and several ratchet teeth are provided circumferentially or axially on the inner side of the positioner 5, which cooperate with the elastic ratchet. The transmission rod 6 can move axially relative to the screw 4 but cannot rotate. Since the positioner 5 is fixed, the transmission rod 6 can rotate relative to the positioner 5 but remains stationary axially. When the transmission rod 6 and the screw 4 rotate simultaneously, the screw 4 can rotate and move downward relative to the positioner 5.

[0032] When the patient rotates the dosage cylinder 10 clockwise, the dosage cylinder 10 extends upward from the pen body tube 2 due to the interaction between the guide sleeve thread and the external thread of the dosage cylinder 10. The button 11 and the transmission rod 8 then move linearly upward. When the patient rotates the dosage cylinder 10 counterclockwise, the above components move in the opposite direction. During dosage adjustment, the patient can observe the required dosage scale through the pen body tube window 21 and the guide sleeve window 71, and then stop rotating the dosage cylinder. During injection, the patient presses the button 11, and the dosage cylinder 10, transmission rod 8, and locking ring 9 form a single unit, rotating downward. Simultaneously, this drives the transmission rod 6 to rotate, which in turn drives the screw 4 to rotate. Under the interaction of the internal thread of the positioner 5 and the external thread of the screw 4, the screw 4 rotates downward and pushes the piston 3 downward linearly. The piston 3 extends into the pen cartridge holder 1, pushing the medication downward, completing the injection. After each injection, the locking ring 9 rises a certain height relative to the transmission link 8. The total stroke of the locking ring 9 corresponds to the total dosage of the medicine in the pen refill holder 1. During repeated adjustments and injections, the locking ring 9 continues to rise until it reaches the top of the transmission link 8, at which point all the medicine has been injected. When the dosage of medicine in the pen refill holder 1 is less than the total dosage at the adjustment setting of the dosing cylinder 10, the dosing cylinder 10 can only adjust the adjustment setting for the remaining dosage of medicine in the pen refill holder 1.

[0033] In this embodiment, by providing a button spring 12, when the patient rotates the dosage cylinder 10 to adjust the dosage, the connection between the transmission linkage 8 and the button spring 12 produces a "tick" sound under the action of the spring force, serving as a prompt sound for the patient to adjust the injection dosage and reminding the patient. Furthermore, when the patient presses the button 11, the button spring 12 can improve the user experience of pressing the injection by providing spring damping.

[0034] In addition, this embodiment has a simple structure and fewer parts, making it easy to manufacture and process, as well as easy for patients to adjust and use.

[0035] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. In this description, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this specification. The illustrative expressions of the above terms in this specification do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples and features described in this specification. The accompanying drawings are merely schematic diagrams and do not represent the actual structure of the various components.

[0036] The above description is merely an embodiment of one or more embodiments of this specification and is not intended to limit the scope of this specification. Various modifications and variations can be made to the one or more embodiments of this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims.

Claims

1. A disposable injection pen with precisely adjustable dosage, characterized in that, The device includes a pen refill holder, a pen body tube, a piston, a screw, a positioner, a transmission rod, a guide sleeve, a transmission connecting rod, a locking ring, a dosage cylinder, and a button. The pen refill holder has a cavity for holding the medication. The positioner is fixedly installed at the connection between the pen refill holder and the pen body tube. The screw has an external thread on its outer wall, and the positioner has an internal thread on its inner wall that mates with the external thread of the screw. The piston is located at one end of the screw, and the other end of the screw passes through the positioner and extends into the transmission rod. One end of the transmission rod is rotatably connected to the positioner, and the other end is axially movable and extends into the transmission connecting rod. The locking ring is located inside the dosage cylinder, and the transmission connecting rod passes through the locking ring and extends into the dosage cylinder. The dosage cylinder rotatably passes through the guide sleeve and extends into the pen body tube. The guide sleeve is located inside the pen body tube and connects to the dosage cylinder. A button spring is provided at the tail end of the dosage cylinder, and one end of the button extends into the dosage cylinder and is connected to the transmission connecting rod through the button spring.

2. The disposable injection pen with precisely adjustable dosage as described in claim 1, characterized in that, The outer wall of the transmission rod is provided with at least one axial groove, and the inner wall of the transmission connecting rod is provided with a boss that cooperates with the axial groove.

3. A disposable injection pen with precisely adjustable dosage as described in claim 2, characterized in that, The outer wall of the transmission connecting rod is provided with an external thread, and the inner wall of the locking ring is provided with a locking key and a convex key that mates with the external thread of the transmission connecting rod.

4. A disposable injection pen with precisely adjustable dosage as described in claim 3, characterized in that, The outer wall of the dose rotating cylinder is provided with an external thread, and the inner wall of the guide sleeve is provided with a guide sleeve thread that mates with the external thread of the dose rotating cylinder.

5. A disposable injection pen with precisely adjustable dosage as described in claim 4, characterized in that, The pen body has a viewing window, and the guide sleeve is fixedly connected to the viewing window of the pen body. The guide sleeve also has a guide sleeve viewing window.

6. A disposable injection pen with precisely adjustable dosage as described in claim 5, characterized in that, The dosing cylinder has multiple settings, each setting of which corresponds to each unit of the drug dosage in the pen refill holder, and the total number of settings of the dosing cylinder is equal to the total number of drug dosage units.

7. A disposable injection pen with precisely adjustable dosage as described in any one of claims 1-6, characterized in that, The locator is provided with two elastic buckles along its axial direction, and the end of the pen refill holder is provided with two tile-shaped elastic buckles. The two elastic buckles are respectively located between the two elastic buckles of the locator, so that the two tile-shaped elastic buckles and the two elastic buckles form a ring.

8. A disposable injection pen with precisely adjustable dosage as described in claim 7, characterized in that, The transmission rod end is provided with an elastic ratchet, and the locator has several ratchet teeth arranged circumferentially or axially on its inner side, which cooperate with the elastic ratchet.

9. A disposable injection pen with precisely adjustable dosage as described in claim 1, characterized in that, The end of the pen refill holder is provided with an external thread for connection to the injection needle.

10. A disposable injection pen with precisely adjustable dosage as described in claim 1, characterized in that, Includes a pen cap, which is detachably fitted over the pen refill holder.

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