Direct answer
Bottle indexing creates a known container position before the dispense command is allowed
An automatic filler must separate, locate and hold the required number of bottles beneath the nozzles, confirm the expected condition and release them without collision or back-pressure damage. Gates, stops, timing screws, starwheels, pucks, servo indexing or moving-fill systems can perform different parts of that task.
How are bottles stopped beneath filling nozzles?
Bottles can be controlled by entry and exit gates, timing screws, starwheels, pockets, pucks or another indexed transfer. The controls create the required pitch, verify the group and coordinate nozzle movement and dispensing. The selection depends on bottle stability, shape, required rate and the surrounding line.
Guide rails alone do not guarantee an accurate nozzle position. A repeatable datum, adequate settling time and control of downstream back-pressure are also needed.
What does no-bottle-no-fill mean?
No-bottle-no-fill means the machine inhibits dispensing when the required bottle condition is not detected. The phrase does not define the sensor, the number of stations covered or whether the system detects a tipped, doubled or badly positioned bottle. Those functions must be stated in the controls description and tested.
For multi-head filling, ask whether a missing bottle stops the complete group or only the affected channel and how the event is recorded.
Why can transparent, dark or reflective bottles change sensor selection?
Optical sensors interact with bottle colour, transparency, reflections, wall thickness, labels and product residue. A sensor that reliably detects one pack may be inconsistent with another. Alternative optical arrangements, background suppression, ultrasonic sensing or mechanical confirmation may be considered according to the application.
Test every confirmed bottle finish under production lighting and include bottles with normal moulding and decoration variation.
When are pucks, timing screws or starwheels useful?
Pucks are useful when bottles need support or a common external handling shape. Timing screws can establish pitch and smooth bottle transfer. Starwheels and pockets provide positive location through rotary or indexed stations. Each solution introduces format parts, cleaning surfaces, storage and changeover requirements.
Use the simplest handling system that proves stable presentation through the required operations. A support method that works at the filler must also release or continue through the capper and labeller as planned.
What should happen when a bottle tips or a queue backs up?
The control sequence should stop or isolate the relevant movement before bottles collide, fall into a hazard area or trigger an uncontrolled dispense. It should define how the operator identifies the location, makes the equipment safe, removes affected packs and restarts without mixing unprocessed and accepted bottles.
Machine guarding, conveyor access and fault recovery must follow the project risk assessment. The UK Health and Safety Executive provides public guidance on packaging machinery and conveyor hazards.
How should bottle indexing be tested?
Test indexing with the smallest, tallest, lightest, least stable, darkest or most transparent confirmed bottles as applicable. Include normal flow, missing bottles, a controlled downstream stop, restart and the approved changeover. Record bottle position, sensor state, nozzle clearance, rejects and the condition of bottles released downstream.
| Test | Evidence | Acceptance question |
|---|---|---|
| Normal group | Repeated bottle pitch and nozzle alignment | Are all bottles correctly located before filling? |
| Missing bottle | Sensor and dispense response | Is product prevented from discharging into an empty position? |
| Downstream stop | Gate, conveyor and bottle state | Does the line hold without damage or uncontrolled release? |
| Restart | First processed and rejected bottles | Can accepted production resume under the agreed procedure? |