An Introduction to Pneumatic and Electric Self Feed Units
A Versatile Unit to Meet a Wide Range of Needs:
Airmachines’ Self Feed Unit combines a motor with a double acting, self lubricating cylinder into a clean line package. The motor can be powered by air or electricity. With the control system and a variety of attachments, the unit can be used for drilling, tapping, screwdriving and nutrunning in many automated operations.
Single or Double Feed to the Motor and Cylinder*:
Incorporated into the design of the tool, this feature enables both the motor and the cylinder to be fed with air through one connection or separately through two connections which can have different air pressures – an advantage when drilling or tapping small holes.
*Applies to pneumatic units only.
Adjustable Stroke Length:
The unit can be set for any stroke from 5/16″ (8mm) to 3″ (75mm) to provide for deep hole drilling applications, while providing a greater clearance for fixtures and indexing tables, among other things. The stroke is adjusted by means of an adjustment screw. An indicator on the upper guard makes set up quick and easy.
Double Acting Air Cylinder to Maintain Set Thrust:
The main advantage delivered by this method of applying thrust is that the set thrust can be maintained throughout the full 3″ (75mm) stroke. This provides greatly improved cycle times as the drill bit will cut more quickly without burring. It will also enable the feed rate to be accurately controlled, thus prolonging small drill life and preventing tap breakage. The control head incorporates valves that control the rate of feed and retraction of the cylinder, as well as porting for dwell control. For manual control, start and stop push buttons are provided, while for partial or fully automatic control, check valves are supplied.
The cycle completion signal can be obtained as a negative signal from the connection on the back of the feed tube. The pressure is removed when the unit has fully retracted. The cycle signal port on the feed tube provides a positive signal as soon as the unit moves forward.
Flexible Mounting Options:
The different mounting brackets make it possible to permanently mount the unit into a dedicated machine for long run production. Alternatively it can be quickly and easily changed for various set ups for short run production.
Generously Outfitted with Many Attachments and Accessories Standard:
The self-feed units come with many attachments as standard features. These include a drill chuck up to 3/8″ (10mm) capacity, 3/8″ or 1/2″ square drives for nutrunners, a ball clutch for screwdrivers, and a collets for tappers. Both single and multiple spindle tapping heads along with multiple spindle drilling heads are available. The units also include a number of standard accessories, such as isolation fittings for remote advance and retract, upper guard with depth indicator, chuck key with drill unit, and collet wrenches with tapping unit.
Optional Accessories for Special Needs:
In addition to the standard accessories, you can take advantage of a number of optional accessories for self-feed units. These include several kits — hydraulic feed control, peck feed control, bottom limit sensing, dwell control and return limit sensing. Other optional accessories are an exhaust collector, bushing mount nose housing, swarf exclusion kit, skip control units and mounting brackets and clamps. A positive signal air valve or electric limit switch that mounts on the guard can also be supplied. It will give a positive signal when the unit is fully retracted in the home position. Air flow restrictors of 10 cfm and 15 cfm (5 l/s and 7 l/s ) can also be supplied as optional extras if the application involved does not require the utilization of the full motor power. This means a savings in compressed air consumption.