Project Overview

A customer developing a next-generation smart lock system encountered a critical issue during product testing. The lock actuator failed to operate consistently during startup, resulting in unreliable unlocking performance and an unacceptable user experience.

As the core actuation component, the solenoid needed to deliver sufficient force instantly while maintaining low power consumption and long service life.

The customer turned to Nextcore Electronic for an engineering solution.

The Challenge

Problem

The smart lock solenoid occasionally failed to actuate during startup.

The issue was particularly noticeable:

• Under low battery conditions

• During cold-start operation

• After extended periods of inactivity

This created a risk of lock malfunction and reduced overall system reliability.

Engineering Analysis

After reviewing the application requirements and evaluating the customer's existing design, the engineering team at Nextcore Electronic identified two primary causes.

Root Cause #1: Excessive Spring Preload

The return spring was designed with a high preload force to ensure secure locking.

However, the spring generated excessive resistance during the initial actuation phase, increasing the force required to move the plunger.

Root Cause #2: Insufficient Initial Pull Force

Although the solenoid met the nominal force specification, its initial force output at the beginning of the stroke was insufficient to overcome the combined resistance of:

• Spring preload

• Mechanical friction

• Lock mechanism resistance

As a result, the plunger occasionally failed to complete the required movement.

Nextcore Electronic Solution

To solve the problem without increasing overall system power requirements, our engineering team implemented several design optimizations.

1. Coil Redesign

The electromagnetic coil was redesigned to improve magnetic force generation at the critical starting position.

Benefits:

• Increased initial pull force

• Faster response time

• Improved startup reliability

2. Spring Force Optimization

The spring characteristics were carefully analyzed and optimized.

Benefits:

• Reduced unnecessary preload force

• Lower actuation resistance

• Improved force balance

3. Plunger Structure Optimization

The plunger geometry and magnetic circuit were redesigned to maximize magnetic efficiency.

Benefits:

• Better magnetic flux utilization

• Higher force output

• Smoother movement throughout the stroke

Results

Following implementation of the optimized design, the smart lock achieved significant performance improvements.

✔ Reliable Actuation

The startup failure issue was completely eliminated, ensuring consistent unlocking performance across all operating conditions.

✔ Reduced Power Consumption

The improved magnetic efficiency allowed the lock to operate using less energy, helping extend battery life.

✔ Extended Product Lifecycle

Lower mechanical stress and optimized force distribution reduced wear on both the solenoid and locking mechanism.

✔ Improved User Experience

The lock delivered faster, smoother, and more dependable operation.

Why Engineering Optimization Matters

Many solenoid failures are not caused by the solenoid itself, but by the interaction between:

• Spring force

• Mechanical load

• Stroke requirements

• Installation conditions

• Power limitations

At Nextcore Electronic, we work closely with customers to analyze the complete application rather than simply selecting a standard solenoid.

By optimizing the electromagnetic design, mechanical structure, and operating parameters together, we help customers achieve:

• Higher reliability

• Lower power consumption

• Longer service life

• Reduced development risk

About Nextcore Electronic

With more than 10 years of experience in designing and manufacturing custom solenoids, solenoid valves, and electromagnets, Nextcore Electronic provides engineering-driven solutions for:

• Smart Locks

• Vending Machines

• Medical Devices

• Industrial Automation

• Automotive Systems

• Gaming Equipment

• Security Applications

Need help solving a solenoid performance challenge?
Contact Nextcore Electronic today to discuss your application and discover how our engineering team can optimize your design for maximum performance and cost efficiency.