Dual chamber cartridge pen

Abstract

The application discloses a double-cavity card type bottle pen and relates to the technical field of injection pens, which comprises a pen shell and a pen core frame which are mutually clamped, a pen cap is clamped on the outer surface of the lower end of the pen core frame, a double-cavity card type bottle is clamped in the pen core frame, different to-be-mixed medicaments are pre-sealed in the double-cavity card type bottle, an injection push rod is inserted into the pen shell, a mixing push rod is threadedly connected to the inside of the injection push rod, the upper part of the mixing push rod is a limiting part, the lower part of the mixing push rod is clamped with the abutting block, the thread directions of the injection push rod and the mixing push rod are opposite, a driving rod is clamped in the inside of the mixing push rod, and the top of the driving rod is clamped with the button. The application integrates the operation entrance of medicament mixing into the top of the pen body, completely conforms to the general use habit of the conventional injection pen that the operation is concentrated on the top, is simple and convenient to operate, eliminates the possibility of action confusion from the operation logic level, significantly reduces the probability of misoperation, and improves the drug safety.

Description

Technical Field

[0001] This invention relates to the field of injection pen technology, specifically to a dual-chamber cartridge pen. Background Technology

[0002] Dual-chamber cartridge vials are widely used for pre-filled formulations that require mixing immediately before use. The accompanying injection pen must simultaneously possess both pre-mixing and quantitative injection functions. Existing technologies, such as the dual-chamber automatic injection pen disclosed in Chinese invention patent application number 202511447384.6, employ a rotating pen cartridge holder at the bottom of the pen body. Through threaded transmission, an internal push rod is axially fed, pushing a piston within the dual-chamber cartridge to complete pre-mixing. This approach places the mixing operation at the bottom of the pen body, completely separating it from the dosage adjustment and injection operation positions at the top, breaking the conventional logic of centralized operation at the top of injection pens. Patients must switch holding positions multiple times to complete the entire process, making it cumbersome and inconvenient. Furthermore, it contradicts mainstream injection pen usage habits, easily leading to operational confusion and errors, and posing potential medication safety risks. Summary of the Invention

[0003] The purpose of this invention is to design a dual-chamber cartridge pen to solve the problem mentioned in the background art that the mixed operation of existing dual-chamber cartridge injection pens is located at the bottom of the pen body, which contradicts the general logic of centralized operation at the top of conventional injection pens. This not only makes the operation cumbersome and inconvenient, but also easily leads to operational errors due to differences in usage habits, posing potential drug safety hazards.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: A dual-chamber cartridge pen includes a pen shell and a refill holder that are interlocked. A pen cap is fitted onto the lower outer surface of the refill holder. A dual-chamber cartridge bottle is fitted inside the refill holder, and the dual-chamber cartridge bottle is pre-filled with different reagents to be mixed. An injection plunger is inserted inside the pen shell. The top of the injection plunger has a button, and a stop block is fixed to the bottom of the injection plunger. The stop block abuts against a piston at the upper end of the dual-chamber cartridge bottle. A drive cylinder is inserted inside the pen shell. A knob for driving the drive cylinder to rotate is rotatably engaged on the outer top of the pen shell. A connecting cylinder is sleeved on the outer surface of the drive cylinder. The bottom end of the connecting cylinder is engaged with the bottom end of the drive cylinder. A digital tube is circumferentially limited and engaged on the outer surface of the connecting cylinder. The outer surface of the digital tube is threadedly connected to the inner surface of the pen shell. An observation window for observing the values ​​on the surface of the digital tube is opened on the surface of the pen shell. A torsion spring is provided between the connecting cylinder and the driving cylinder. The top end of the torsion spring is engaged with the upper part of the connecting cylinder, and the bottom end of the torsion spring is engaged with the lower part of the connecting cylinder. The button abuts against the driving cylinder, and a return spring is provided between the button and the pen shell. A cavity is opened inside the driving cylinder, and the upper part of the injection push rod is inserted into the cavity. A driving ratchet is provided below the connecting cylinder, and a clutch spring is provided between the driving ratchet and the connecting cylinder. A driving rack is fixed to the inner wall of the bottom end of the connecting cylinder, and a clutch rack is fixed to the outer wall of the top end of the driving ratchet. The clutch rack and the driving rack mesh with each other. A limit block is fixed to the upper side inside the driving ratchet, and a limit groove that mates with the limit block is opened on the side wall of the injection push rod. A threaded hole that mates with the thread of the injection push rod is provided on the lower side inside the driving ratchet. The injection plunger is internally threaded with a mixing plunger. The upper part of the mixing plunger is a limiting part, and the lower part of the mixing plunger is engaged with the abutment. The threads of the injection plunger and the mixing plunger are opposite in direction. A drive rod is internally engaged with the mixing plunger, and the top of the drive rod is engaged with the button. This invention integrates the mixing plunger completely within the injection plunger, employing a coaxial nested reverse thread pair for mixing and feeding. This eliminates the need for an additional threaded structure at the bottom of the pen body for rotating the cartridge holder, and does not increase the pen's radial dimensions or overall length. While fully retaining dosage adjustment and automatic injection functions, it achieves integrated dual-chamber mixing functionality. Furthermore, the drug mixing operation inlet is integrated to the top of the pen body, perfectly aligning with the common practice of "top-centralized operation" in conventional injection pens. This simplifies and facilitates operation, eliminates the possibility of confusion from an operational logic perspective, significantly reduces the probability of misoperation, and improves medication safety.

[0005] Preferably, the lower end of the inner wall of the injection push rod is fixed with a threaded block that mates with the threaded portion of the mixing push rod; the outer diameter of the limiting portion of the mixing push rod is larger than the outer diameter of the threaded portion; so that the limiting portion of the mixing push rod is limited at the threaded block at the bottom of the injection push rod when it rotates down, and when the drive rod continues to rotate, the mixing push rod rotates freely and no longer moves down, while the medicine in the dual-chamber cartridge is mixed.

[0006] Preferably, the inner surface of the hybrid push rod is in close contact with the outer surface of the drive rod; the drive rod is configured as a "D" shape; rotating the drive rod can drive the hybrid push rod to rotate, thereby achieving reliable circumferential limiting transmission.

[0007] Preferably, a first one-way ratchet is engaged with the outer surface of the upper end of the drive rod, and a first one-way ratchet tooth that cooperates with the first one-way ratchet is fixed at the upper end of the inner surface of the drive cylinder; the first one-way ratchet and the first one-way ratchet tooth form a one-way locking structure for the mixing transmission circuit, which only allows the drive rod to rotate in the mixing feed direction and restricts reverse rotation, preventing the mixing push rod from springing back after mixing, avoiding piston reset that could cause drug backflow and chamber re-separation, ensuring a stable and reliable mixing state, and eliminating the risk of drug mixing failure.

[0008] Preferably, the connecting cylinder includes a positioning cylinder and a movable cylinder. The positioning cylinder is engaged with the inner wall of the upper end of the pen shell, and the movable cylinder is sleeved on the outer surface of the driving cylinder. The top of the movable cylinder and the bottom of the positioning cylinder abut against each other, and the digital tube is circumferentially limited and sleeved on the outer surface of the movable cylinder. The top of the torsion spring is engaged with the inner wall of the positioning cylinder, and the bottom of the torsion spring is engaged with the lower end of the movable cylinder. The positioning cylinder keeps the cylinder stationary, and the movable cylinder rotates with the driving cylinder to tighten the torsion spring and achieve energy storage. The outer surface of the injection plunger is threaded with a dose adjustment ring, which is circumferentially limited and engaged within the cavity to move axially. The axial position of the dose adjustment ring limits the maximum feed stroke of the injection plunger, corresponding to the set injection dose, thus achieving precise quantitative drug delivery control. Combined with the digital display, this ensures the accuracy of the drug delivery dose. The drive ratchet is engaged inside the fixing block, which is engaged with the inner wall of the pen casing. A screw block is engaged at the bottom of the fixing block. The screw hole is located in the middle of the screw block. A check rack that mates with the drive ratchet is fixed to the inner wall of the screw block above the screw hole. By fixing the radial position of the drive ratchet, the check rack restricts the reverse rotation of the drive ratchet, ensuring the unidirectional nature of the injection feed, stabilizing the transmission during the injection process, preventing the injection push rod from retracting and causing drug backflow, and further ensuring the accuracy of the injection dosage and the safety of the injection.

[0009] Preferably, the knob includes a mixing knob and an adjustment knob; the adjustment knob is rotatably engaged with the outer surface of the top of the pen shell, and a second one-way ratchet is locked at the middle position of the adjustment knob; a second one-way ratchet tooth that mates with the second one-way ratchet is fixed to the inner wall of the top of the positioning cylinder; the second one-way ratchet is sleeved on the outer surface of the drive cylinder, a first transmission rack is fixed to the inner surface of the second one-way ratchet, and a second transmission rack that meshes with the first transmission rack is fixed to the outer surface of the drive cylinder; the mixing knob is rotatably engaged with the outer wall of the top of the adjustment knob, the button is locked to the inner side of the mixing knob, and the return spring is located between the button and the adjustment knob; by separating the input ends of the mixing operation and the dose adjustment operation and concentrating them on the top of the pen body, the operation area is completely unified, and the patient does not need to cut The entire operation can be completed simply by changing the grip position, conforming to the user habit of centralized operation at the top, and the operation logic is clear and intuitive. At the same time, the cooperation of the second one-way ratchet and the second one-way ratchet tooth forms a one-way locking structure for the dose adjustment circuit, preventing the dose from rebounding due to reverse rotation of the adjustment knob. This ensures that the set dose will not fall back on its own without external force, ensuring stable dose adjustment and guaranteeing the accuracy of the administered dose. Furthermore, the meshing design of the first and second transmission racks transmits the rotational power of the adjustment knob to the drive cylinder through the one-way ratchet, simultaneously completing the torsion spring energy storage. This allows the dose adjustment and energy storage actions to be completed synchronously, with a simple and reliable transmission path. Meanwhile, the design of the return spring provides axial return force to the button, automatically pushing the button back to the initial position after injection, achieving automatic button reset after injection, and providing a clear tactile feedback.

[0010] Preferably, a top block is symmetrically fixed to the side wall of the adjustment knob, and the end wall of the top block cooperates with the second one-way ratchet. The design of the top block makes it possible for the second one-way ratchet to squeeze the top block when the adjustment knob is rotated in the opposite direction under the action of external force, and the second one-way ratchet is compressed under the action of the top block. By repeating this process, the dose reset operation can be completed, ensuring that the dose adjustment operation can be performed normally during the next injection.

[0011] Preferably, the adjustment knob has an opening, and a movable toothed ring engages with the opening. The top of the positioning cylinder is fixed with a positioning tooth that mates with the movable toothed ring. The bottom surface of the return spring abuts against the top surface of the movable toothed ring, and the top surface of the return spring abuts against the bottom surface of the button. This allows the movable toothed ring to rotate with the adjustment knob during dose adjustment, alternately engaging and disengaging with the fixed positioning tooth, generating a tactile feel and sound, providing clear feedback on the dose adjustment level. The patient can judge the adjustment level through feel and sound, improving the accuracy of dose adjustment and operational awareness.

[0012] Preferably, a support cylinder is fixed at the center of the adjustment knob, and a sound-emitting cylinder is sleeved on the outer wall of the support cylinder. A latch is provided on the side wall of the sound-emitting cylinder, and an elastic locking block that cooperates with the latch is fixed on the outer wall of the support cylinder. A compression spring is provided between the sound-emitting cylinder and the support cylinder. The inner wall of the support cylinder tightly abuts against a limiting cylinder. An adjustment ring is threadedly connected to the inner wall of the mixing knob. The inner wall of the adjustment ring is fixedly connected to the limiting cylinder through a support arm. Grooves that cooperate with the support arm are symmetrically provided on the support cylinder and the sound-emitting cylinder. When the mixing push rod rotates and moves until the mixed medicine is completely mixed and emits sound while spinning freely, the limiting cylinder moves to release the limiting of the elastic locking block. After the sound-emitting cylinder is released from the limiting, it moves down quickly under the restoring force of the compression spring and strikes the adjustment knob to emit sound, which is used to remind the patient that the medicine has been mixed. The mixing is completed without visual observation.

[0013] Preferably, a docking block is fixed circumferentially at the bottom of the sound-emitting tube, and a docking groove that mates with the docking block is provided on the inner surface of the adjustment knob. This allows the patient to know that dosage adjustment is required after drug mixing, and simply continue to rotate the mixing knob to rotate the adjustment knob and complete the dosage adjustment. This achieves a seamless connection between "drug mixing operation - dosage adjustment", allowing the patient to complete both steps by rotating the top knob without changing any operating parts. The operation process is highly consistent, further reducing the complexity of operation and the learning cost.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention embeds the drug mixing transmission mechanism inside the injection plunger, and transmits hybrid power through the top drive rod, so that the operation entry for drug mixing, dosage adjustment, and injection triggering area are all concentrated at the top of the pen body. This fully conforms to the common operation logic of "top-centralized operation" of conventional injection pens, making operation simple and convenient, avoiding confusion and operation errors caused by differences in operating habits, and significantly improving medication safety.

[0015] This invention fully embeds the mixing plunger within the internal cavity of the injection plunger, achieving mixing and feeding through a reverse threaded pair. It eliminates the need for an additional rotating threaded structure for the pen refill holder at the bottom of the pen body, thus not increasing the pen's radial dimensions or overall length. While integrating dual-cavity mixing functionality, the overall product size is essentially the same as a conventional single-cavity injection pen, offering significantly better portability than rotating refill holder designs. Furthermore, the refill holder and pen shell maintain a fixed, snap-fit ​​connection without relative rotation, structurally eliminating issues such as contaminant intrusion into gaps, loose needle interfaces leading to leakage, and accidental needle punctures caused by refill holder rotation. This enhances the product's long-term reliability and hygiene safety.

[0016] This invention utilizes a linked structure of a support cylinder, a sound-emitting cylinder, and a limiting cylinder to trigger an axial impact sound from the sound-emitting cylinder simultaneously with the completion of drug mixing. This provides auditory feedback to the patient, indicating the completion of the mixing process. Patients can accurately confirm the mixing point without visual observation, making it suitable for core user groups such as diabetic patients and elderly patients with poor vision.

[0017] After the mixing is completed, the sound tube moves down synchronously, and the bottom docking block is engaged with the docking groove of the adjustment knob, so that the mixing knob and the adjustment knob can automatically achieve circumferential linkage. The patient can complete the drug mixing and dosage adjustment in sequence by rotating the top mixing knob throughout the process. There is no need to change the operating parts. The operation process is smooth and seamless, which greatly reduces the patient's learning cost and operation complexity. Attached Figure Description

[0018] Figure 1 This is a front view schematic diagram of the structure of the present invention; Figure 2 This is a schematic cross-sectional view of the structure of the present invention; Figure 3 This is a front view schematic diagram of the pen refill holder structure in this invention; Figure 4 This is a front view schematic diagram of the structure of the dual-cavity cartridge bottle in this invention; Figure 5 This is a frontal cross-sectional view of the dose adjustment component in this invention; Figure 6 This is a front cross-sectional view of the automatic injection component in this invention; Figure 7 This is a front cross-sectional view of the clutch assembly in this invention; Figure 8 This is a front cross-sectional view of the structure of the dose adjustment anti-retrograde component in this invention; Figure 9 This is a three-dimensional structural diagram of the dose-adjustable sound generation method in this invention; Figure 10 This is a three-dimensional structural diagram of the adjustment knob in this invention; Figure 11 This is a front sectional view of the adjustment knob in this invention; Figure 12 This is a three-dimensional structural diagram of the second one-way ratchet in this invention; Figure 13 This is a front view schematic diagram of the structure of the pharmaceutical mixing component in this invention; Figure 14 This is a frontal cross-sectional view of a partial structure of the pharmaceutical mixing component in this invention; Figure 15 This is a top view schematic diagram of the structure of the pharmaceutical mixing component in this invention; Figure 16This is a frontal cross-sectional schematic diagram of the structure in this invention that produces sound after the medicine is mixed; Figure 17 This is a top cross-sectional view of the structure in this invention that produces sound after the medicine is mixed. Figure 18 This is a front view schematic diagram of the structure of the drive cylinder in this invention.

[0019] The image shows: 110. Pen casing; 111. Observation window; 120. Pen refill holder; 130. Pen cap; 140. Dual-chamber cartridge bottle; 150. Injection plunger; 151. Stop block; 152. Limiting groove; 153. Threaded block; 210. Drive cylinder; 211. Cavity; 212. First one-way ratchet; 213. Second transmission rack; 220. Adjustment knob; 221. Opening; 222. Top block; 223. Connecting groove; 230. Positioning cylinder; 231. Second one-way ratchet; 232. Positioning tooth; 240. Movable cylinder; 241. Drive rack; 250. Digital display; 260. Second one-way ratchet; 261. First transmission rack; 270. Movable gear ring; 310. Torsion spring; 320. Dosage adjustment ring; 330. Button; 340. Return spring; 350. Drive ratchet; 351. Clutch rack; 352. Limit block; 360. Clutch spring; 370. Fixing block; 380. Screw block; 381. Screw hole; 382. Anti-reverse rack; 410. Hybrid push rod; 420. Drive rod; 430. Hybrid knob; 440. First one-way ratchet; 510. Support cylinder; 511. Elastic locking block; 520. Sound-emitting cylinder; 521. Bayonet; 522. Connecting block; 530. Compression spring; 540. Adjusting ring; 550. Limiting cylinder; 560. Support arm; 570. Slotted. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0021] Therefore, the following detailed description of embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely illustrates some embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0022] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] The embodiments of the present invention are as follows: See Figure 1-18 As shown, the dual-chamber cartridge pen includes a pen shell 110, a refill holder 120, a pen cap 130, a dual-chamber cartridge bottle 140, and an injection plunger 150. The pen shell 110 and the refill holder 120 are axially interlocked and fixed, with no relative rotational movement between them. The pen cap 130 is fitted onto the lower outer surface of the refill holder 120 to protect the needle interface during daily storage. The dual-chamber cartridge bottle 140 is interlocked and fixed inside the refill holder 120. The bottle has two independent chambers formed by a separator piston, each pre-filled with different medications to be mixed. The injection plunger 150 is coaxially inserted inside the pen shell 110, and a stop block 151 is fixed at its bottom. The stop block 151 abuts against the injection piston at the upper end of the dual-chamber cartridge bottle 140 to transmit axial thrust during injection. A limiting groove 152 is formed on the side wall of the injection plunger 150 along the axial direction. The drive cylinder 210 is coaxially inserted into the upper inner cavity of the pen shell 110, and has a cavity 211 inside. The upper part of the injection push rod 150 is slidably inserted into the cavity 211 and can move relative to it along the axial direction. The connecting cylinder is sleeved on the outside of the drive cylinder 210 and is specifically divided into two parts: a positioning cylinder 230 and a movable cylinder 240. The positioning cylinder 230 is snapped and fixed to the inner wall of the upper end of the pen shell 110, keeping it stationary in the circumferential direction. The movable cylinder 240 is sleeved on the outer surface of the drive cylinder 210 and can rotate synchronously with the drive cylinder 210. Its top end is aligned with the bottom end of the positioning cylinder 230. The digital tube 250 is circumferentially limited and sleeved on the outer surface of the movable tube 240, and the outer surface is threadedly engaged with the inner surface of the pen shell 110; the pen shell 110 has an observation window 111 on its surface, which can intuitively display the dosage value on the surface of the digital tube 250; the torsion spring 310 is set between the connecting tube and the driving tube 210, with its top end locked to the inner wall of the positioning tube 230 and its bottom end locked to the lower end of the movable tube 240; when adjusting the dosage, the driving tube 210 drives the movable tube 240 to rotate, causing the two ends of the torsion spring 310 to generate relative torsion, thereby achieving energy storage; A drive ratchet 350 is located below the connecting cylinder, with a clutch rack 351 fixed to its top outer wall. A drive rack 241 is correspondingly fixed to the bottom inner wall of the connecting cylinder. A clutch spring 360 is located between the drive ratchet 350 and the connecting cylinder, normally pushing the drive ratchet 350 downwards to keep the clutch rack 351 and drive rack 241 separated. The drive ratchet 350 is engaged inside a fixing block 370, which is fixed to the inner wall of the pen housing 110. A screw block 380 is engaged at its bottom. The screw block 380 has a screw hole 381 at its center that engages with the injection plunger 150. A non-reverse rack 382 is fixed to the inner wall of the screw block 380 above 81, which engages unidirectionally with the outer peripheral teeth of the drive ratchet 350 to restrict the reverse rotation of the drive ratchet 350; a limit block 352 is fixed to the upper side inside the drive ratchet 350, which slides axially with the limit groove 152 on the side wall of the injection push rod 150 to achieve circumferential synchronous transmission; a dose adjustment ring 320 is also threadedly connected to the outer surface of the injection push rod 150. The dose adjustment ring 320 is circumferentially limited and engaged in the cavity 211, and its axial position corresponds to the set injection dose, which is used to limit the maximum feed stroke of the injection push rod 150 to achieve quantitative drug delivery; A threaded block 153 is fixed to the lower end of the inner wall of the injection plunger 150. The mixing plunger 410 is coaxially inserted inside the injection plunger 150, with its lower part being a threaded section that engages with the threaded block 153. The upper part of the mixing plunger 410 is a limiting section, the outer diameter of which is larger than the outer diameter of the threaded section, and its outer surface is smooth. This limiting section is used to axially limit the mixing plunger 410 when it descends to the threaded block 153. The threads of the injection plunger 150 and the mixing plunger 410 have opposite directions of rotation. When the mixing plunger 410 rotates circumferentially, it can generate axial displacement relative to the injection plunger 150. Its bottom end engages with the stop block 151, thereby pushing the separator piston inside the dual-chamber vial 140 to move and open the drug chamber. The mixing plunger 410 has an internal... A drive rod 420 is coaxially engaged. The drive rod 420 has a "D" shaped cross-section, and its outer surface is tightly fitted with the inner surface of the mixing push rod 410 to achieve reliable circumferential limiting transmission. At the same time, the two can slide relative to each other along the axial direction, which is compatible with the button pressing action during injection. The top of the drive rod 420 is engaged with the button 330 to transmit the rotational power of the top to the mixing push rod 410. The upper outer surface of the drive rod 420 is also engaged with a first one-way ratchet 440, and the upper upper surface of the inner surface of the drive cylinder 210 is correspondingly fixed with a first one-way ratchet 212. The two engage in one-way meshing to form a mixing anti-reverse structure, which only allows the drive rod 420 to rotate in the mixing feed direction to prevent the push rod from springing back after mixing and causing the drug to flow back. The adjustment knob 220 is rotatably engaged with the outer surface of the top of the pen housing 110, and a second one-way ratchet 260 is engaged at its intermediate position. A second one-way ratchet tooth 231, which mates with the second one-way ratchet 260, is fixed to the inner wall of the top of the positioning cylinder 230, forming a one-way anti-reverse structure for the dosage adjustment circuit. The second one-way ratchet 260 is sleeved on the outside of the drive cylinder 210, with a first transmission rack 261 fixed to its inner surface. A second transmission rack 213 is correspondingly fixed to the outer surface of the drive cylinder 210, and their meshing transmits rotational power. A top block 222 is symmetrically fixed to the side wall of the adjustment knob 220, and the end wall of the top block 222 mates with the second one-way ratchet 260. Reverse rotation of the adjustment knob 220 can compress the second one-way ratchet 260, causing it to contract radially. Disengaging the ratchet allows for dose adjustment; the adjustment knob 220 has an opening 221, within which a movable toothed ring 270 engages, and a positioning tooth 232 is fixed to the top of the positioning cylinder 230; the bottom surface of the return spring 340 abuts against the top surface of the movable toothed ring 270, and the top surface abuts against the bottom surface of the button 330, providing axial preload to the movable toothed ring 270; during dose adjustment, the movable toothed ring 270 rotates with the knob, alternately engaging and disengaging with the positioning tooth 232, generating tactile and audible feedback on the gear position; the mixing knob 430 is rotatably engaged on the outer wall of the top of the adjustment knob 220, and the button 330 is limited and engaged on the inner side of the mixing knob 430; the return spring 340 is located between the button 330 and the adjustment knob 220, providing axial return force to the button after it is pressed; The support cylinder 510 is fixed at the middle position of the adjusting knob 220, and a sound-generating cylinder 520 is sleeved on its outer wall. A compression spring 530 is provided between the two. A slot 521 is opened on the side wall of the sound-generating cylinder 520, and an elastic block 511 is fixed on the outer wall of the support cylinder 510. Under normal conditions, the elastic block 511 is engaged with the slot 521, restricting the axial movement of the sound-generating cylinder 520 and keeping the compression spring 530 in a compressed and energy-storing state. An adjusting ring 540 is threadedly connected to the inner wall of the mixing knob 430. The inner wall of the adjusting ring 540 is fixedly connected to the limiting cylinder 550 through the support arm 560. Slots 570 are symmetrically opened on the support cylinder 510 and the sound-generating cylinder 520. The support arm 560 passes through the slot 570 and can slide axially. When the mixing knob 430 is rotated, the adjusting ring 540 drives the limiting cylinder 550. 0. Synchronous axial downward movement; when the mixing push rod 410 moves to the point where the drug is completely mixed and enters the idling state, the limiting cylinder 550 moves downward synchronously to release the radial support of the elastic locking block 511. The sound-emitting cylinder 520 moves downward rapidly under the restoring force of the compression spring 530, and its bottom strikes the adjusting knob 220 to produce a sound, indicating that the drug mixing is complete. A docking block 522 is fixed circumferentially at the bottom of the sound-emitting cylinder 520, and a docking groove 223 is correspondingly opened on the inner surface of the adjusting knob 220. After the sound-emitting cylinder 520 moves downward, the docking block 522 is engaged in the docking groove 223, so that the mixing knob 430 and the adjusting knob 220 achieve circumferential linkage through the sound-emitting cylinder 520. Continuing to rotate the mixing knob 430 will synchronously drive the adjusting knob 220 to complete the dosage adjustment, realizing seamless connection between mixing and dosage adjustment. The working principle is as follows: In use, first remove the pen cap 130 and install the double-ended needle. Rotate the top mixing knob 430 clockwise, which drives the mixing push rod 410 to rotate via the drive rod 420. The reverse threaded pair pushes the separator piston down to open the chamber. After mixing is complete, the mixing push rod 410 is limited to idle rotation, and at the same time, the sound tube 520 strikes to indicate that mixing is complete. The mixing knob 430 and the adjustment knob 220 are automatically linked. Continue to rotate the mixing knob 430 to drive the adjustment knob 220 to rotate synchronously, completing the dosage setting and the energy storage of the torsion spring 310. When injecting, press the top button 330. The drive tube 210 moves down to make the drive rack 241 mesh with the clutch rack 351. The torsion spring 310 releases energy to drive the drive ratchet 350 to rotate, which in turn drives the injection push rod 150 to advance axially to complete the injection.

[0025] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship conventionally understood by those skilled in the art. These terms are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described herein. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the specific embodiments described above. Therefore, any modifications or equivalent substitutions to the present invention, as well as all technical solutions and improvements that do not depart from the spirit and scope of the invention, are covered within the scope of the claims of the present invention.

Claims

1. A dual-chamber cartridge pen, comprising a pen shell (110) and a pen refill holder (120) that are interlocked with each other, wherein a pen cap (130) is fitted onto the lower outer surface of the pen refill holder (120); a dual-chamber cartridge bottle (140) is fitted inside the pen refill holder (120), wherein different reagents to be mixed are pre-filled inside the dual-chamber cartridge bottle (140); an injection plunger (150) is inserted inside the pen shell (110), wherein a button (330) is provided on the top of the injection plunger (150), and a stop block (151) is fixed at the bottom of the injection plunger (150), wherein the stop block (151) abuts against the piston at the upper end inside the dual-chamber cartridge bottle (140); A drive cylinder (210) is inserted inside the pen shell (110). A knob for driving the drive cylinder (210) to rotate is rotatably engaged on the outer top of the pen shell (110). A connecting cylinder is sleeved on the outer surface of the drive cylinder (210). The bottom end of the connecting cylinder is engaged with the bottom end of the drive cylinder (210). A digital tube (250) is circumferentially limited and engaged on the outer surface of the connecting cylinder. The outer surface of the digital tube (250) is threadedly connected to the inner surface of the pen shell (110). An observation window (111) is opened on the surface of the pen shell (110) for observing the values ​​on the surface of the digital tube (250). A torsion spring (310) is provided between the connecting cylinder and the driving cylinder (210). The top end of the torsion spring (310) is engaged with the upper part of the connecting cylinder, and the bottom end of the torsion spring (310) is engaged with the lower part of the connecting cylinder. The button (330) and the drive cylinder (210) abut against each other, and a return spring (340) is provided between the button (330) and the pen shell (110); a cavity (211) is provided inside the drive cylinder (210), and the upper part of the injection push rod (150) is inserted into the cavity (211); a drive ratchet (350) is provided below the connecting cylinder, and a clutch spring (360) is provided between the drive ratchet (350) and the connecting cylinder; a drive rack (2) is fixed to the inner wall of the bottom end of the connecting cylinder. 41), a clutch rack (351) is fixed to the outer wall of the top of the drive ratchet (350), and the clutch rack (351) and the drive rack (241) mesh with each other; a limit block (352) is fixed to the upper side inside the drive ratchet (350), a limit groove (152) is opened on the side wall of the injection push rod (150) to cooperate with the limit block (352), and a threaded hole (381) is provided on the lower side inside the drive ratchet (350) to cooperate with the threaded part of the injection push rod (150); characterized in that: The injection push rod (150) is internally threaded with a mixing push rod (410). The upper part of the mixing push rod (410) is a limiting part, and the lower part of the mixing push rod (410) is a threaded part. The bottom end of the mixing push rod (410) is engaged with the abutment (151). The threads of the injection push rod (150) and the mixing push rod (410) are opposite. The mixing push rod (410) is internally engaged with a drive rod (420), and the top of the drive rod (420) is engaged with the button (330).

2. The dual-cavity cartridge pen according to claim 1, characterized in that, The lower end of the inner wall of the injection push rod (150) is fixed with a threaded block (153) that mates with the threaded portion of the mixing push rod (410); the outer diameter of the limiting portion of the mixing push rod (410) is larger than the outer diameter of the threaded portion.

3. The dual-cavity cartridge pen according to claim 2, characterized in that, The inner surface of the hybrid push rod (410) is in close contact with the outer surface of the drive rod (420); the drive rod (420) is configured as a "D" shape.

4. The dual-cavity cartridge pen according to claim 3, characterized in that, The upper outer surface of the drive rod (420) is engaged with a first one-way ratchet (440), and the upper upper surface of the inner surface of the drive cylinder (210) is fixed with a first one-way ratchet tooth (212) that cooperates with the first one-way ratchet (440).

5. The dual-cavity cartridge pen according to claim 4, characterized in that, The connecting cylinder includes a positioning cylinder (230) and a movable cylinder (240). The positioning cylinder (230) is snapped onto the upper inner wall of the pen shell (110). The movable cylinder (240) is sleeved on the outer surface of the driving cylinder (210). The top of the movable cylinder (240) and the bottom of the positioning cylinder (230) abut against each other. The digital cylinder (250) is circumferentially limited and sleeved on the outer surface of the movable cylinder (240). The top of the torsion spring (310) is engaged with the inner wall of the positioning cylinder (230), and the bottom of the torsion spring (310) is engaged with the lower end of the movable cylinder (240); The injection plunger (150) is threaded with a dose adjustment ring (320) on its outer surface. The dose adjustment ring (320) is circumferentially limited and engaged in the cavity (211) for axial movement. The drive ratchet (350) is engaged inside the fixing block (370), the fixing block (370) is engaged inside the pen shell (110), and a screw block (380) is engaged at the bottom of the fixing block (370); the screw hole (381) is located at the middle position inside the screw block (380); a backstop rack (382) that cooperates with the drive ratchet (350) is fixed on the inner wall of the screw block (380) above the screw hole (381).

6. The dual-cavity cartridge pen according to claim 5, characterized in that, The knob includes a mixing knob (430) and an adjustment knob (220); the adjustment knob (220) is rotatably engaged with the outer surface of the top of the pen shell (110), and a second one-way ratchet (260) is engaged at the middle position of the adjustment knob (220); a second one-way ratchet tooth (231) that cooperates with the second one-way ratchet (260) is fixed on the inner wall of the top of the positioning cylinder (230). The second one-way ratchet (260) is sleeved on the outer surface of the drive cylinder (210), and the inner surface of the second one-way ratchet (260) is fixed with a first transmission rack (261). The outer surface of the drive cylinder (210) is fixed with a second transmission rack (213) that meshes with the first transmission rack (261). The mixing knob (430) is rotated and engaged on the outer wall of the top of the adjusting knob (220), the button (330) is engaged on the inner side of the mixing knob (430), and the reset spring (340) is located between the button (330) and the adjusting knob (220).

7. The dual-cavity cartridge pen according to claim 6, characterized in that, The adjustment knob (220) has a top block (222) symmetrically fixed on its side wall, and the end wall of the top block (222) cooperates with the second one-way ratchet (260).

8. The dual-cavity cartridge pen according to claim 7, characterized in that, The adjustment knob (220) has an opening (221), and a movable toothed ring (270) is engaged in the opening (221). The top of the positioning cylinder (230) is fixed with a positioning tooth (232) that cooperates with the movable toothed ring (270). The bottom surface of the return spring (340) abuts against the top surface of the movable toothed ring (270), and the top surface of the return spring (340) abuts against the bottom surface of the button (330).

9. The dual-cavity cartridge pen according to claim 8, characterized in that, A support cylinder (510) is fixed at the middle position of the adjusting knob (220). A sound-emitting cylinder (520) is fitted on the outer wall of the support cylinder (510). A slot (521) is opened on the side wall of the sound-emitting cylinder (520). An elastic block (511) that cooperates with the slot (521) is fixed on the outer wall of the support cylinder (510). A compression spring (530) is provided between the sound-emitting cylinder (520) and the support cylinder (510). The inner wall of the support cylinder (510) tightly abuts against the limiting cylinder (550). An adjusting ring (540) is threadedly connected to the inner wall of the mixing knob (430). 40) The inner wall is fixedly connected to the limiting cylinder (550) by the support arm (560). The support cylinder (510) and the sound-emitting cylinder (520) are symmetrically provided with slots (570) that cooperate with the support arm (560). When the mixing push rod (410) rotates and moves until the mixed medicine is completely mixed and makes a sound, the limiting cylinder (550) moves to release the limiting of the elastic block (511). After the sound-emitting cylinder (520) is released from the limiting, it moves down quickly under the restoring force of the compression spring (530) and hits the adjusting knob (220) to make a sound, which is used to remind the patient that the medicine has been mixed.

10. The dual-cavity cartridge pen according to claim 9, characterized in that, The bottom of the sound tube (520) is fixed with a docking block (522). The inner surface of the adjustment knob (220) is provided with a docking groove (223) that cooperates with the docking block (522). This allows the patient to know that when the drug needs to be adjusted after mixing, they only need to continue to turn the mixing knob (430) to drive the adjustment knob (220) to rotate and complete the dosage adjustment.

Images