Speaker Driver Assembly: Coil Position and Glue
How an earphone speaker driver line is specified: coil position against distortion, rivet force on the frame, glue amount, and what a run-off checks.
How a speaker driver line is specified
Coil position is the whole game on a speaker line. A coil that sits off centre still plays — it simply fails a distortion test. So the line is specified around the driver size, the magnet and pole pieces, the coil, the glue and its cure, and the distortion limit your customer applies.
Station sequence
Frame, rivet, pole pieces, magnet and voice coil each arrive on their own vibration plate, so orientation is settled before the part reaches a fixture. The frame is loaded, the rivet and pole pieces follow, the magnet goes in, two riveting units set the frame, glue is dispensed onto the frame, and the PCB is placed on the assembled frame one piece at a time before the driver drops into a tray.
The two riveting units run in sequence with the glue station, which is how the line holds a steady rate without an operator handling the rivet. Control is a Delta PLC with a Wenview touch screen, with a safety grating and guards on the moving parts.
What decides reject rate
- Coil centring. Off-centre coils pass a listening test and fail distortion, so the check has to be a measurement, not an ear.
- Glue amount. Too much creeps into the gap and stiffens the coil; too little lets the PCB lift after cure.
- Rivet force. Force that bows the frame moves the pole pieces and changes the gap after everything was aligned.
- Pole piece orientation. A reversed pole piece passes assembly and fails the magnetic test.
What we need from you
- Driver drawing or BOM: frame, pole pieces, magnet, coil and PCB
- Coil specification, and the distortion limit with the test method you use
- Glue type, dispense amount and cure profile
- Target cycle time, annual volume and shifts per day
How the project runs
Quote from drawing, tooling design, build, then run-off with your parts in our plant in Chashan, Dongguan. The drawing set is agreed before metal is cut, and the distortion test method is agreed before run-off so the acceptance is measurable. Two years warranty.
Send a drawing to [email protected] or call +86-18123647785. Related lines: O-ring assembly machines, drill chuck assembly machines.
Machines for this part: Speaker Assembly Machine — the models we build, with station count and cycle time per line.
Send the drawing for this line. We come back with station layout, cycle time and price.
A quote normally takes three working days once the part information is complete. If something is missing we tell you which drawing is needed instead of guessing a price.
- 012D drawing or STEP file, and the sub-parts
- 02Material and surface finish of each component
- 03Target cycle time, annual volume, shifts per day
- 04The defect you cannot ship — leak, torque, appearance
- 05Bottle neck thread or mating part