Why Are Springs and Stampings Essential in Inhalers?

Springs and stampings are critical to the performance, reliability, and consistency of inhalers. They ensure smooth actuation, accurate dosing, and mechanical durability across a wide range of drug delivery platforms.

What types of springs are used in inhalers, and how are they applied?

Different inhaler devices use a variety of springs depending on their actuation mechanism:

• Compression springs are commonly used to control the return mechanisms of button actuation in pressurized metered-dose inhalers (pMDIs) and their valves, as well as in systems like SMIs and DPIs that pierce the capsule.
• Torsion springs enable rotational movement in reusable inhaler systems or dry powder inhalers (DPIs).
• Extension springs are found in components that require tension-based activation, such as dose counters or locking features.
• Stampings provide structural support, precise alignment, and actuation interfaces within inhaler devices, enabling reliable function and compact design.
• Piercing needles for DPIs

Each spring and stamping part is engineered for consistent force delivery, minimal fatigue, and long-term mechanical stability.

Which types of inhalers use springs and stamped components?

Springs and metal stampings are present in most modern inhalers, including:

• pMDIs (Pressurized Metered-Dose Inhalers) and inhaler valves: Springs enable consistent press-and-release action, ensuring precise medication delivery.
• DPIs (Dry Powder Inhalers): Components support dosing mechanisms and internal movement of drug reservoirs.
• SMIs (Soft Mist Inhalers): These systems often include highly complex stamped and spring-loaded parts for energy storage and precise release.

Custom-designed stamped parts also help create structural enclosures, guides, and actuator supports.

Why are springs and stamped parts so critical in inhaler performance?

• Precise dosing: Springs and stamped parts control key mechanisms, such as drug release, ensuring each dose is accurate and consistent.
• Firing synchronization: In devices like DPIs or pMDIs, these components ensure the medication is released at the right moment about the patient's inhalation.
• Mechanical reliability: They endure repeated cycles and must maintain their shape, force, and function throughout the inhaler's lifespan.
• Miniaturization and design efficiency enable the integration of complex mechanical functions into compact spaces, thereby optimizing the device's size and ergonomics.
• User feedback and feel: Springs provide tactile resistance or a "click" that confirms proper activation, enhancing the user experience.

Springs and stamped parts must meet stringent medical-grade standards to ensure performance throughout a product's lifecycle.

Need support for your inhaler project?

RPK Medical partners with device manufacturers worldwide to develop and industrialize high-performance springs, stampings, and assemblies tailored to respiratory drug delivery.

Contact our team to discuss your next inhaler program.

As inhalers evolve to become smarter, smaller, and more user-friendly, the role of miniature mechanical components, such as springs and stampings, is more critical than ever. They're not just parts — they're enablers of life-changing therapies.