Syringe Selectable Metering Grooves Locking Pins
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Syringes with fixed dosages present challenges for users with poor vision and reduced dexterity, as precise alignment with markings is required for accurate dosage, and existing solutions are either inflexible or overly complex.
Innovation Solution
A syringe design featuring a cavity with movable locking pins and grooves that allow for selectable metering, enabling easy adjustment and precise dispensing of specific dosages, with indicator markings for user orientation and a mechanism to evacuate air and excess liquid, ensuring accurate dosing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If separate syringes are provided for separate doses, then dosage accuracy is improved, but device complexity and inventory requirements worsen
Solution Approach 1:
The syringe employs a dynamic dosing mechanism where the plunger can be positioned at multiple selectable depths corresponding to different dosages (e.g., 0.5ml, 1.0ml, 1.5ml markings). This allows a single syringe to dynamically adapt to different dosage requirements through simple plunger repositioning rather than requiring multiple fixed-dose syringes.
Solution Approach 2:
The syringe barrel is segmented into multiple dosage sections marked at specific intervals (0.5ml, 1.0ml, 1.5ml). These segments allow the user to select and dispense precise portions of the total volume by positioning the plunger at the desired marking, enabling one syringe to replace multiple fixed-dose syringes.
2Measurement precision
If precise alignment with markings is required, then dosage accuracy is improved, but ease of operation worsens for users with poor vision and dexterity
Solution Approach 1:
The syringe incorporates visually distinct markings and color-coded indicators at different dosage levels (0.5ml, 1.0ml, 1.5ml). These enhanced visual cues make it easier for users with vision impairments to identify and align with the correct dosage markings without requiring fine motor skills for precise alignment.
Solution Approach 2:
The syringe design includes self-aligning features where the plunger naturally stops at predetermined dosage markings during the filling process. This self-stopping mechanism reduces the need for users to manually align the plunger with markings, thereby assisting users with limited dexterity while maintaining dosage accuracy.
3Reliability
If the cavity is overfilled to evacuate air, then air removal is improved, but liquid loss increases
Solution Approach 1:
The syringe is designed to be intentionally overfilled beyond the desired dosage mark during the filling process. This preliminary overfilling action ensures that any air bubbles are pushed out through the needle before the plunger is repositioned to the exact dosage marking, thereby eliminating air pockets without requiring additional evacuation steps that would cause further liquid loss.
Solution Approach 2:
The design accepts that some liquid loss during overfilling is inevitable but converts this potential harm into a benefit by ensuring complete air evacuation. The excess liquid that is lost during overfilling is offset by the elimination of air bubbles that would otherwise compromise the accuracy and reliability of the administered dosage.
Data Source
AI summary
A needle syringe has a plunger and a needle for filling and dispensing liquid from the cavity. The cavity has finger clip with movable locking pins. The plunger has at least one set of grooves corresponding to a specific dosage for the needle syringe, the specific dosage of the groove being demarked by a marking ledge that indicates a change to a deeper depth section of the groove. The locking pins are configured to rest in the at least one set of grooves, such that when the plunger is removed, the locking pins pass within a first shallow section of the groove, pass over the ledge, and continue to pass in the deeper depth section of the groove. When the plunger is depressed in a first partial dispensing movement, the locking pins pass in the deeper depth section of the groove until the plunger depression is temporarily locked when the locking pins reach the ledge, where the dose remaining in the cavity is the specific dosage.