固定剂量注射装置及其致动组件
By adding a limiting structure and spring design to the automatic injection device, the push rod is ensured to move within the set range, which solves the problem of inaccurate drug dosage control, achieves accuracy and safety of injection dosage, and simplifies the operation process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG SUMMED MEDTECH CO LTD
- Filing Date
- 2025-03-03
- Publication Date
- 2026-07-17
AI Technical Summary
Traditional automated injection devices lack effective limiting structures, resulting in inaccurate drug dosage control, which may lead to over- or under-injection, affecting treatment efficacy and increasing medication risks.
An additional limiting structure, including a slider and a groove, is added to limit the movement range of the push rod. Automatic injection is achieved through the design of push rod spring and sleeve spring. The combination of limiting and positioning components ensures the fixation of the needle cap, thereby ensuring the accuracy and safety of the injection stroke.
It achieves accurate and safe injection dosage, reduces the risk of accidental punctures, is easy to operate, and realizes automated injection process.
Smart Images
Figure CN224506018U_ABST
Abstract
Claims
1. An actuation assembly of a fixed dose injection device, characterized in that, The actuation components of the fixed-dose injection device include: The actuator extends a predetermined length along a virtual axis; A push rod is mounted on the actuator sleeve and is movable relative to the actuator sleeve; A push rod spring is disposed between the actuator sleeve and the push rod; The limiting structure has a slider and a groove. The groove is provided on the actuator sleeve and extends along the axis for a predetermined groove length. The slider is provided on the push rod in cooperation with the groove, and the free end of the slider extends toward the actuator sleeve and falls into the groove. When the push rod is pushed by the elastic force of the push rod spring, the push rod moves relative to the actuator sleeve along the axis. The movement range of the slider is limited by the predetermined groove length, thereby limiting the movement range of the push rod. A sleeve, fitted onto the actuator rod, and movable relative to the actuator rod; and A sleeve spring is disposed between the actuator rod and the sleeve. When the sleeve is pushed by the elastic force of the sleeve spring, the sleeve moves relative to the actuator rod along the axis.
2. The actuation assembly of a fixed dose injection device of claim 1, wherein, The actuation components of the fixed-dose injection device also include: The positioning structure has a slot, a cantilever, a front positioning slot and a rear positioning slot. The front positioning slot and the rear positioning slot are spaced apart along the axis and are provided on the push rod. The front positioning slot and the slot are provided on the actuating sleeve along the axis. The cantilever is located in the slot and extends from the actuating sleeve along the axis. A positioning protrusion is provided on the free end of the cantilever and extends toward the push rod. The push rod moves between a starting position and a ending position. When the push rod moves from the ending position to the starting position, it gradually approaches the actuator sleeve while compressing the push rod spring until the push rod is in the starting position and the positioning protrusion is engaged in the front positioning groove. When the push rod moves from the starting position to the ending position, the positioning protrusion disengages from the front positioning groove, and the push rod moves under the push of the push rod spring until it is in the ending position and the positioning protrusion is engaged in the rear positioning groove.
3. A fixed dose injection device characterized in that, The fixed-dose injection device includes: The pen barrel has a front end and a rear end, and the pen barrel has an accommodating space extending from the front end toward the rear end along a virtual axis. The actuation component according to any one of claims 1 to 2 is disposed in the accommodating space and located adjacent to the rear end; A needle cap extends a predetermined length along a virtual axis and has a front end and a rear end at opposite ends of the extended length. The needle cap is movably disposed in the accommodating space and positioned adjacent to the front end, and is movable along the axis between a starting position and a ending position by the actuating component. When the needle cap is in the starting position, the rear end of the needle cap retracts to be flush with the front end of the pen barrel; when the needle cap is in the ending position, a portion of the rear end of the needle cap is exposed beyond the front end of the pen barrel. The limiting structure has a limiting member and a positioning member. The positioning member is disposed on the inner wall surface of the pen barrel, and the limiting member is disposed on the needle cover. When the needle cover is located in the termination position, the limiting member is hooked onto the positioning member to restrict the needle cover from moving again.
4. The fixed dose injection device of claim 3, wherein, The limiting member has a groove, an extension arm, and a limiting protrusion. The groove is formed on the needle cover along the axis. The extension arm is located in the groove and extends from the needle cover along the axis. The limiting protrusion is provided on the free end of the extension arm and extends toward the pen barrel.
5. The fixed dose injection device of claim 4, wherein, The positioning element has a protrusion that is located on the inner wall of the pen barrel and extends toward the needle cap, with the protrusion having a guide surface and a stop surface on its two sides, respectively.
6. The fixed dose injection device of claim 3, wherein, The fixed-dose injection device also includes a syringe sleeve, which is fitted inside the needle cap.
7. The fixed dose injection device of claim 3, wherein, The fixed-dose injection device also includes an extended pen barrel disposed at the front end of the pen barrel.
8. The fixed dose injection device of claim 7, wherein, The fixed-dose injection device also includes a front cover, which is detachably mounted on the extension pen barrel and closes the opening at the front end of the pen barrel.
9. The fixed dose injection device of claim 8, wherein, The fixed-dose injection device also includes a rear cover disposed on the rear end of the pen barrel, which closes the opening at the rear end of the pen barrel.