Full-Line Dispensing Solution for Loudspeakers

When a production line under your management simultaneously runs external-magnet automotive loudspeakers, internal-magnet receivers, and several smart speaker models with cone diaphragms, the dispensing process immediately becomes a series of critical decisions: which dispensing approach applies to the three-piece magnetic circuit assembly? Are diaphragm center adhesive dispensing and voice coil lead adhesive dispensing the same process step? For each model change, how many fixtures need readjustment and how many hours of robot teaching will be required?

This is not a challenge faced by only one factory. High-mix, low-volume production with fast delivery has become the norm in the electroacoustic industry. Dispensing is precisely the process in both the magnetic circuit section and vibration system that relies most heavily on manual skill and suffers the most efficiency losses from product changeover. Before purchasing equipment, many enterprises have not yet clarified one core principle: select the right process first, then choose the equipment. A wrong process judgment will cause even the most advanced machinery to fail at dispensing along the correct adhesive path.

This page avoids stacking excessive parameters or repeating details of single-station solutions. Instead, from a perspective of "holistic overview + model selection", it clarifies in one place the commonalities across all loudspeaker dispensing scenarios and the underlying selection logic. We first establish the most core concept:

What is vision-tracking dispensing? A camera identifies the position and orientation of workpieces in real time, and the dispensing head automatically applies adhesive by synchronously tracking the trajectory, requiring no fixtures and no line stoppage.

Three key features:

• Fixture-free positioning: Workpieces can be placed arbitrarily; the vision system automatically identifies and compensates for deviations, eliminating dependence on precision fixtures.
• In-line dynamic tracking: The dispensing head operates synchronously with the assembly line, eliminating the need to stop the line for workpieces and ensuring stable and controllable cycle times.
• Flexible production changeover: Model switching can be completed in minutes by recalling or creating new vision templates, enabling one platform to cover multiple process steps.

With this underlying logic understood, the following four major scenarios and selection table can be easily mapped to your specific applications.

Loudspeaker dispensing can be divided into four process lines by application position. They correspond to different vibration system components, distinct adhesive path patterns, and four specialized solutions from Songqi Intelligence respectively. Clearly defining the boundaries of each process is the first step in solution selection.

1. External-Magnet T-Yoke Dispensing Process: Annular bonding of the three-piece magnetic circuit assembly (T-yoke, magnet steel, washer) in external-magnet loudspeakers. With a magnetic gap width of only 0.3–0.8 mm, adhesive volume, placement accuracy and overflow amount directly determine production yield and acoustic performance, making it a critical quality checkpoint for preventing adhesive overflow into the magnetic gap.
2. Internal-Magnet U-Yoke Dispensing Process: Dispensing for the cup-shaped magnetic circuit of internal-magnet (bowl magnet) structures, consisting of U-yoke, ring magnet and washer. With deep narrow internal cavities and strict concentricity requirements, stable dispensing accuracy is difficult to achieve with conventional fixture-based positioning.
3. Center Adhesive Dispensing Solution: Bonding adhesive for spider-to-voice coil and cone-to-voice coil connections in the vibration system, as well as the bonding between the dust cap (center dome) and the diaphragm center. It often involves complex curved surfaces such as cones and domes, placing high demands on the adaptive posture control of the dispensing valve.
4. Figure-8 Adhesive & Voice Coil Dispensing: Voice coil lead fixing adhesive (also referred to as lead adhesive, wire adhesive, or scribe adhesive). It is precisely applied along the arc section of the lead wire, wrapping the root to prevent breakage. The adhesive must be free of stringing and sagging to avoid voice coil burnout.

To distinguish them in brief: the first two processes address how to securely bond the magnetic circuit, while the latter two solve how to fix the vibration system components. A single loudspeaker typically requires multiple processes in both the magnetic circuit section and the vibration system, which is precisely the core value of the vision-tracking platform in delivering unified coverage for all these operations.

The most intuitive way to apply the aforementioned process scenarios to specific products is summarized in the table below. Structured by the framework of "Loudspeaker Type → Corresponding Vibration System Components → Recommended Dispensing Process → Value of Vision-Tracking", it enables direct matching for your application scenarios:

Note: The above table presents typical corresponding relationships. The specific bonding positions, adhesive types and process steps shall be subject to the actual product BOM and prototype verification. If a loudspeaker involves both magnetic circuit section and vibration system processes, the production line should be planned with a combined process scheme.

Whether for external-magnet structures, internal-magnet structures or vibration systems, the pain points of conventional manual and semi-automatic dispensing share highly consistent root causes. Recognizing these common characteristics is essential to understanding why vision-tracking serves as a unified solution rather than isolated single-point optimizations.

Slow product changeover and high fixture costs. Each product model typically requires custom precision fixtures, with a single set often costing thousands to tens of thousands of yuan. Production changeover requires re-teaching and reprogramming, taking hours or even days. Hesitancy to accept rush orders and reluctance to fulfill small-batch orders is a widespread predicament among many electroacoustic manufacturers.

Difficult access to narrow working spaces. Space is constrained in areas such as cup-shaped deep cavities of the magnetic circuit and curved diaphragm surfaces. Manual handheld operation or simple mechanisms can hardly consistently align with the ideal adhesive path, and dispensing placement accuracy depends entirely on operator dexterity.

Uncontrollable dispensing angle and trajectory. Annular and arc-shaped adhesive paths require precise tracking. Manual visual control of adhesive overflow and eccentricity leads to significant process variation. Adhesive breakage or buildup most frequently occurs at multi-turn closed sections and start-end joints.

Poor consistency and lack of traceability. Product quality is highly dependent on the proficiency of skilled operators, and staff turnover directly causes fluctuations in cycle time and production yield. Key process data such as adhesive volume, dispensing position and speed are not systematically recorded. When batch-wide abnormal noise or voice coil rubbing issues arise, the root cause is difficult to pinpoint.

Songqi Intelligence's vision-tracking dispensing addresses all the aforementioned common pain points through a single unified hand-eye coordination platform, rather than applying piecemeal fixes to individual process steps.

Fixture-Free Operation A 5-megapixel industrial camera identifies the position, angle and posture of workpieces in real time. Workpieces can be placed in any orientation, and the vision system automatically performs positioning and deviation correction, completely eliminating dependence on physical fixtures.

Real-Time Deviation Correction Dimensional and geometric tolerances of incoming workpieces, as well as placement deviations, are adaptively compensated by the vision system. Backed by the self-developed YMC-08-01 motion control card and patented 360° rotating R-axis, the system maintains a stable operation accuracy of ±0.02 mm, fundamentally eliminating failure modes such as eccentricity and adhesive overflow into the magnetic gap.

Non-Stop In-Line Operation The dispensing head operates synchronously with the production line conveyor belt, completing dynamic tracking dispensing without stopping the line for workpieces, and achieving seamless integration into in-line production workflows.

Flexible Production Changeover Model changeover only requires recalling or creating new vision templates, with calibration completed in minutes. Compared with conventional methods, changeover efficiency is significantly improved, and overall equipment effectiveness (OEE) is enhanced accordingly.

Full Traceability & No Hidden Costs The self-developed vision software records key parameters including adhesive volume, dispensing speed and position in real time, and supports deep integration with MES and ERP systems. As fully self-developed proprietary software, it incurs no annual licensing fees or version upgrade charges, and enables one-step troubleshooting.

Process selection is determined by application positions, while equipment selection depends on production volume, number of product models and precision requirements. Below is a ready-to-use decision-making framework:

Step 1: Define the process based on structural type

• External-magnet structure → Adopt External-Magnet T-Yoke Dispensing Process for the magnetic circuit section;
• Internal-magnet structure → Adopt Internal-Magnet U-Yoke Dispensing Process for the magnetic circuit section;
• Products with dust cap / center bonding → Adopt Center Adhesive Dispensing Solution for the vibration system;
• Products requiring voice coil lead fixation → Adopt Figure-8 Adhesive & Voice Coil Dispensing for the vibration system.

Most products adopt combined processes, which can be disassembled process by process with reference to Table 3.

Step 2: Evaluate the number of product models and production changeover frequency For production lines with high-mix, low-volume production and tight delivery schedules, priority should be given to the flexible changeover capability of vision-tracking systems. Production lines with low-mix, high-volume production can also benefit from this technology, but they place greater emphasis on cycle time and continuous operation stability.

Step 3: Assess precision requirements and curved surface complexity

• Flat magnetic circuits and regular annular adhesive paths: 4-axis models (embedded / cabinet type) are fully capable;
• Center adhesive dispensing on complex curved surfaces such as cones and domes, or special-shaped diaphragms: 5-axis models are preferred (X / Y / Z / R / A axes, equipped with the national patented three-dimensional rotary dispensing device, Patent No. ZL202421031124.1). The R-axis enables annular bonding, and the A-axis adjusts the dispensing valve posture, specially designed for complex curved surfaces.

Step 4: Consider production volume and production line configuration

• For existing conveyor belt production lines requiring in-situ replacement and seamless upgrade: choose embedded models that can be directly mounted across the conveyor belt;
• For scenarios requiring independent workstations or large-format / multi-station operations: choose cabinet models to form a self-contained closed-loop system.

When final comparison and selection are required based on full-series model parameters and configurations, please refer to the Vision-Tracking Dispensing Machines product page, or contact Songqi for one-on-one solution design services.

**Pitfall 1: Center adhesive equals figure-8 adhesive.** The two processes differ in both application positions and adhesive types. Center adhesive is used for bonding diaphragms / dust caps to voice coils and spiders; figure-8 adhesive is designed for fixing voice coil leads. Confusing the two processes will lead to misalignment between equipment configuration and adhesive path planning.

**Pitfall 2: Internal-magnet design equals external-magnet design.** They adopt distinct magnetic circuit structures: the external-magnet design uses a flat-plate magnetic circuit consisting of a three-piece T-yoke assembly, while the internal-magnet design features a cup-shaped magnetic circuit with a U-yoke. They differ in dispensing paths, deep cavity accessibility and concentricity control challenges, so their solutions cannot be directly applied interchangeably.

**Pitfall 3: Dispensing is merely "applying a ring of adhesive".** In practice, it involves multi-dimensional requirements such as overflow prevention in magnetic gaps, curved surface bonding, lead wire fixation, and controlled adhesive morphology (no stringing, no sagging, full and uniform deposition). Failure in any single link may lead to voice coil rubbing, abnormal noise or lead breakage.

**Implementation Recommendations:**

1. First sort out the vibration system components in your loudspeaker BOM, and mark which belong to the magnetic circuit section and which belong to the vibration system;
2. Refer to the selection table in Section 3 of this page to confirm the corresponding process for each product model;
3. Preliminarily determine the equipment configuration (4-axis / 5-axis, embedded / cabinet type) in accordance with the decision framework in Section 6;
4. Apply for free prototype dispensing verification, and confirm the adhesive path, production yield and cycle time with actual equipment and samples before finalizing the solution.

Sukiauto provides **free process solution design + free prototype dispensing testing**: after you send samples, our engineering team will conduct dispensing trials with actual equipment and issue a complete prototype test report, allowing you to verify the actual performance before making a decision. If your production line is troubled by slow changeover and poor dispensing consistency, you may start with a selection table to first clarify which process fits your production needs.

• Company: Dongguan Sukiauto Intelligent Technology Co., Ltd. (SUKIAUTO)
• Address: Unit 4, 9th Floor, Building 2 (Daotong Zhigu), approximately 160 meters northeast of the Plaza of Dongcheng Foreign Economic Industrial Park, Huijing Road, Dongcheng Sub-district, Dongguan City, Guangdong Province
• Tel: 13761860627
• Email: service@sukiauto.cn
• Services: Free prototype testing · 1-on-1 dedicated after-sales support · 7×24 hour response · Lifetime maintenance

This page serves as an overview and selection guide for loudspeaker dispensing solutions. The process classifications, selection logic and equipment capabilities listed herein are based on Sukiauto's internal technical documents and publicly available process materials in the electroacoustic industry. The specific product selection, process parameters and equipment configuration shall be subject to actual prototype verification and the process solution confirmed by both parties.