Vacuum components

An ejector makes vacuum from compressed air by the Venturi effect, compact and fast, suited to intermittent pick and place. An electric pump is more energy-efficient for continuous high-flow suction. Ejectors consume air the whole time they hold, so factor in air cost.

NBR is general-purpose and tolerates oily surfaces, silicone suits food and high temperature, fluoro rubber suits chemicals. Bellows cups absorb height variation and suit curved surfaces. Porous items like cartons need a higher-flow ejector to make up for leakage.

Theoretical force equals vacuum level times cup area: a 40 mm cup at -60 kPa gives about 75 N. Apply a safety factor of at least 2 for horizontal lifts and 4 for vertical or fast moves. Robot acceleration adds substantial load beyond static weight.

Typically a clogged vacuum filter, worn or hardened cups, or a leak at a fitting. Check and replace the filter element first, as it clogs most often. A dirty silencer on the ejector also reduces achievable vacuum.

Replace them when the lip is cracked, hardened or worn out of shape, or when achievable vacuum drops noticeably below its new level. Frequency depends on the cup material, workpiece roughness and cycle count. Keeping spare cups of the same code avoids long stoppages.

Yes, a vacuum filter between the cup and the pump or ejector stops paper dust, chips and oil vapour. Without it, dust clogs the ejector nozzle or wears the pump. Check the element often because a clogged filter slows evacuation time.

A vacuum switch confirms that the cup has a firm grip before the robot or mechanism moves the workpiece. Set the threshold a sensible margin below normal vacuum level to avoid false alarms. The signal also gives early warning of a torn cup or a leak.

When vacuum is simply switched off, light parts or large cups may cling for a fraction of a second. Use a short blow-off pulse into the cup line to break the vacuum immediately. Many ejectors include a built-in release valve for this.