Sirsalliyan Small Air Compressor

Air Pressure

Inventors Notes – Switching Electronic Air Pressure Regulation

My Asparagus harvester invention utilizes pneumatic cylinders to cut the individual spears, and the stroke length has to right on the money every time.  If the pressure goes up the stroke length becomes longer, and if the pressure goes down the stroke length shortens.

Too much pressure and the piston rod will bottom out against the front cylinder head, and not enough pressure will reduce the stroke length an cause the blade to not cut all the way through the spear or even not reaching the spear at all. Allowing the piston to bottom out against the front head will eventually damage the cylinder.

The asparagus harvester has 14 air cylinders mounted on the header arranged across the asparagus bed.  Each piston rod is equipped with a sharp blade with a slight bit of overlap with the blades next to it. The cylinders are angled down toward the ground and when they extend the blade severs the spear slightly below ground level requiring a stroke length of about 20 inches. Typically the extension stroke takes around 35 to 40 milliseconds.

An optical detection system locates the spears and sends a signal to open the air valve for the cylinder corresponding to the co-ordinates of the spear to be cut.  The harvester is moving forward at between 20 and 30 inches per second, and so the blades must cut the spear and get back up out of the way of any spears that are not quite tall enough to harvest.

Asparagus spears emerge from the bed in a random pattern with random heights.  At any moment during harvesting there may be as many as 5 or 6 cylinders operating at the same time, or none at all. You might have 10 feet with nary a spear, and 18 spears in the next 24 inches.

Because these cylinders are very fast acting they require high flow rates at a constant stable air pressure.  While stroking, the cylinder will be consuming around 165 cubic feet per minute of air. Six cylinders operating at once would require a whopping 990 cubic feet per minute.

With such large swings in flow and rapidly varying air consumption the mechanical air regulator will have a significant variation in the pressure drop, which will have a detrimental affect on the stroke length of the cylinders.

We can, however, use another approach to regulating the air pressure.  We can use a switching electronic air pressure regulation scheme.  With this approach we replace the mechanical pressure regulator with an on or off electric air valve with a high flow rate.

We can then use an accurate analog pressure transducer to open the valve whenever the pressure drops below the set point, and shut off when the pressure is at or above the set point.

The valve has a very low pressure drop unlike the mechanical regulator. The valve can handle the flow required by multiple cylinders without the air pressure drooping that the mechanical regulators end up with.

There will be small pressure spikes or what is known in electronics as a ripple in the pressure.  By properly sizing the manifold I can filter out the small pressure ripples.

About the Author

New Products, Ideas, Inventions: Who invented the electric water heater

Invention help for small inventors: Latest Amazing Scientific Inventions

Inventions, patents, and online marketing: What is a Microcontroller?

Air Pressure Monitor Kit $55.99 Air Pressure Monitor Kit

Experiment to Demonstrate the Strength of Air Pressure $44.99 Experiment to Demonstrate the Strength of Air Pressure - Giclee Print

High Pressure; Air Shock Absorber $168.99 High Pressure; Air Shock Absorber; Expanded Length 20.37 in.; Sold In Pairs;

Pneupac babyPAC High Pressure Air Hose $257.36 Pneupac babyPAC High Pressure Air Hose

Air Pressure Switch Kleinn Horns Air Pressure Switch 2145 $21.81 KLEINN HORNS PRESSURE SWITCH, SOLD INDIVIDUALLY -- 110 psi on; 145 psi off; Features heavy duty tank-mount that regulates the air pressure in your tank; Wired to the compressor and turns the air compressor on and off automatically.. Auto Parts Warehouse has extensive Kleinn Horns Air Pressure Switch catalogs.We are now offering FREE shipping on all Kleinn Horns Air Pressure Switch orders over $50.00. Our secure kleinn horns air pressure switch catalog is available every hour of everyday. Shop with confidence for all your kleinn horns air pressure switch needs. Kleinn Horns Air Pressure Switch are In Stock and available today. Save up to 60% off dealer price on your next Kleinn Horns Air Pressure Switch purchase. Our online catalog contains a wide selection of the OEM and aftermarket parts you need at unbeatable prices

Pressure Air-Flo Gloves $44.95 Alpinestars Pressure Air-Flo Gloves A lightweight, leather and Air-Flo mesh, short-cuff glove. Ideal for summer street riding with a combination of effective venting and robust construction for comfort and safety in warm riding conditions. Features: Full-grain leather palm with Clarino reinforcement Lightweight and comfortable stretch air mesh on top panel Fingertips protected by a layer of perforated leather Comfortable and cool finger internal forchettes TPR knuckle details Wrist strap closure for a secure fit **Closeouts are limited to stock on hand**

Air Suspension Pressure Switch Viair Air Suspension Pressure Switch 90217 $30.92 VIAIR SEALED PRESSURE SWITCH, SOLD INDIVIDUALLY -- 30 amps; 110 psi on, 145 psi off; Comes with 1/8 in. NPT male port fitting; Sealed to ensure moisture resistance.. Auto Parts Warehouse has extensive Viair Air Suspension Pressure Switch catalogs.We are now offering FREE shipping on all Viair Air Suspension Pressure Switch orders over $50.00. Our secure viair air suspension pressure switch catalog is available every hour of everyday. Shop with confidence for all your viair air suspension pressure switch needs. Viair Air Suspension Pressure Switch are In Stock and available today. Save up to 60% off dealer price on your next Viair Air Suspension Pressure Switch purchase. Our online catalog contains a wide selection of the OEM and aftermarket parts you need at unbeatable prices

Air Pressure Gauge Autometer Air Pressure Gauge 2620 $50.54 autometer z-series mechanical air pressure gauge 2-1/16 in. 0 to 150 psi includes 6 ft. nylon tubing and 1/8 to 1/4 in. npt adapter fittings features a rugged air core meter and subtle all black design for a factory look designed for precision movement and extreme accuracy recommends blow memory kit copper tubing gauge mounting cup gauge panel mounting angle ring and nylon tubing auto parts warehouse has extensive autometer air pressure gauge catalogs.we are now offering free shipping on all autometer air pressure gauge orders over $50.00. our secure autometer air pressure gauge catalog is available every hour of everyday. shop with confidence for all your autometer air pressure gauge needs. autometer air pressure gauge are in stock and available today. save upto 60% off dealer price on your next autometer air pressure gauge purchase. our online catalog contains a wide selection of the oem and aftermarket parts you need at unbeatable prices

Prospera Air Pressure Eye Massager $79.99 This massager delivers gentle air pressure to soothe your eye muscles and temples. The 2 heat settings bring warmth to the eye area for added comfort.

AIRHEAD 120V Hi-Pressure Air Pump $44.29 AIRHEAD HI PRESSURE AIR PUMP W/ PRESSURE RELEASE VALVE120V Hi-Pressure Air PumpAirhead's 120V Hi-Pressure Air Pump with pressure release valve quickly inflates and deflates. Best used for towables, boats, rafts, trampolines and other large inflatables. Featues 4 valve adapters, an accordian style ho

Air Suspension Pressure Switch Viair Air Suspension Pressure Switch 90111 $30.92 VIAIR AIR SUSPENSION PRESSURE SWITCH, SOLD INDIVIDUALLY -- For 12-volt systems only (up to 40 amps); 110 psi on, 150 psi off (with a tolerance of +/- 5 percent of specified pressures); Comes with a built-in relay and 1/8 in. NPT male port fitting; Moisture-resistant and tested to endure over 10,000 cycles.. Auto Parts Warehouse has extensive Viair Air Suspension Pressure Switch catalogs.We are now offering FREE shipping on all Viair Air Suspension Pressure Switch orders over $50.00. Our secure viair air suspension pressure switch catalog is available every hour of everyday. Shop with confidence for all your viair air suspension pressure switch needs. Viair Air Suspension Pressure Switch are In Stock and available today. Save up to 60% off dealer price on your next Viair Air Suspension Pressure Switch purchase. Our online catalog contains a wide selection of the OEM and aftermarket parts you need at unbeatable prices

Hi-Pressure Air Pipe Markers $2.3 In-stock identimark economy pipe markers are the most economical way to label indoor pipes. Pipe markers securely identify contents of pipes without falling off! Pressure-sensitive vinyl with adhesive backing permanently marks pipes in one, quick application. Marker reads: Hi-pressure air.

Lo-Pressure Air Pipe Markers $2.3 In-stock identimark economy pipe markers are the most economical way to label indoor pipes. Pipe markers securely identify contents of pipes without falling off! Pressure-sensitive vinyl with adhesive backing permanently marks pipes in one, quick application. Marker reads: Lo-pressure air.

Elmer's: Mythbusters Power of Air Pressure $12.99 Have a gas with 'The Deadly Belch' and other air-powered experiments! In this kit, you'll get to the bottom of air pressure. You might not even notice the air around you, but it packs a powerful punch. Can it cause your stomach to explode? Will it help your bones predict the weather? If you get the air free, can you save your house during a tornado?For ages 9 and up. Type: Board Games Gender: Unisex Age: Child

VIAIR 90150 PSI Air Pressure Regulator $43.64 Viair inline pressure regulator may be used to regulate air pressure from an air tank to any pressure between 0 to 200 PSI. This is useful for installations that supply air to locking differentials and air tools. The regulator also provides an easy to read gauge that allows adjustment of inline pressure a compression fitting for tank pressure side and a T fitting that will allow regulated pressure to be fed to two locations. Regulate air pressure at any point between 0 PSI and 200 PSI. Locking adjustment dial. Mounting bracket included. Includes the following brass fittings: Tfitting (1/4 inch NPT female x 1/4 inch NPT female x 1/4 inch NPT male) compression fitting for 1/4 air line 1/4 NPT Plug. Great for adjusting pressure for air locking differentials.

A-668W Air Pressure Massage Chair in $2099 The A-668 Air Pressure Massage Chair is the ultimate massage chair providing shiatsu massage deep tissue massage and a level of comfort unmatched by any reclining massage chair of its kind Designed to provide users with the most luxurious therapeutic...

A-668B Air Pressure Massage Chair in $2049 The A-668 Air Pressure Massage Chair is the ultimate massage chair providing shiatsu massage deep tissue massage and a level of comfort unmatched by any reclining massage chair of its kind Designed to provide users with the most luxurious therapeutic...

Air $3.95 Six entertaining new books have been added to Science Alive Children will get a thrill out of participating in simple, fun experiments that help show how different scientific principles work. They will also be inspired by history boxes that offer short biographies of scientists and inventors. All you need is the air that you breathe...and a few simple household materials This book examines the properties of air using simple experiments to help demonstrate air pressure and expansion, how flight is achieved, and how to estimate the amount of oxygen in air.

AmStar 1/2'' Air Pressure Regulator with Gauge $57.95 Pneumatic equipment that operates at higher than recommended pressure can cause excess torque, force and wear and can waste compressed air. Operating below specified pressure can cause machines to fail to meet their design performance specifications. Therefore, precise air pressure control is essential to efficient operation of air powered equipment. An air line regulator is a specialized control valve which reduces upstream supply pressure level to a specified constant downstream pressure.Features:? Regulates air pressure of the air line? Self-relieving style units? Features three position non-rising knob-push to lock, pull to adjust, detach to make tamper resistant? Polished brass valve set - regulated pressure will not drift.? Efficient aspirator (minimum pressure drop) - quick response - high cycles - higher productionSpecifications:? 1/2'' NPT Inlet/Outlet? 250 SCFM Max Flow? 5-125 PSIG Adjustment Range

Non-Equilibrium Air Plasmas at Atmospheric Pressure $300.14 Atmospheric-pressure plasmas continue to attract considerable research interest due to their diverse applications, including high power lasers, opening switches, novel plasma processing applications and sputtering, EM absorbers and reflectors, remediation of gaseous pollutants, excimer lamps, and other noncoherent light sources. Atmospheric-pressure plasmas in air are of particular importance as they can be generated and maintained without vacuum enclosure and without any additional feed gases. Non-Equilibrium Air Plasmas at Atmospheric Pressure reviews recent advances and applications in the generation and maintenance of atmospheric-pressure plasmas. With contributions from leading international researchers, the coverage includes advances in atmospheric-pressure plasma source development, diagnostics and characterization, air plasma chemistry, modeling and computational techniques, and an assessment of the status and prospects of atmospheric-pressure air plasma applications. The extensive application sections make this book attractive for practitioners in many fields where technologies based on atmospheric-pressure air plasmas are emerging.

NonEquilibrium Air Plasmas at Atmospheric Pressure $446 Atmosphericpressure plasmas continue to attract considerable research interest due to their diverse applications, including high power lasers, opening switches, novel plasma processing applications and sputtering, EM absorbers and reflectors, remediation of gaseous pollutants, excimer lamps, and other noncoherent light sources. Atmosphericpressure plasmas in air are of particular importance as they can be generated and maintained without vacuum enclosure and without any additional feed gases. NonEquilibrium Air Plasmas at Atmospheric Pressure reviews recent advances and applications in the generation and maintenance of atmosphericpressure plasmas. With contributions from leading international researchers, the coverage includes advances in atmosphericpressure plasma source development, diagnostics and characterization, air plasma chemistry, modeling and computational techniques, and an assessment of the status and prospects of atmosphericpressure air plasma applications. The extensive application sections make this book attractive for practitioners in many fields where technologies based on atmosphericpressure air plasmas are emerging. Author: Becker, K. H./ Kogelschatz, U./ Schoenbach, K. H. Series Title: Series in Plasma Physics Binding Type: Hardcover Number of Pages: 682 Publication Date: 2004/11/29 Language: English Dimensions: 9.49 x 6.51 x 1.71 inches

1/4 Inch Pressure Gauge Air Filter Regulator Compressor#OT852 $6.07 Air Filter Regulator Compressor 1/4 Inch Pressure Gauge

Airhead Watersports / AIRHEAD 120V Hi-Pressure Air Pump / AHP-120HP $49.64 Airhead Watersports - AIRHEAD 120V Hi-Pressure Air Pump - AHP-120HP

ABSOLUTE OUTDOOR / AIR PUMP, UNIV, HIGH PRESSURE 1 / P120BLK99 $60.67 ABSOLUTE OUTDOOR - AIR PUMP, UNIV, HIGH PRESSURE 1 - P120BLK99

His Magdeburg Hemispheres Experiment to Demonstrate the Strength of Air Pressure $34.99 His "Magdeburg Hemispheres" Experiment to Demonstrate the Strength of Air Pressure - Giclee Print

Wind and Air Pressure $6.79 No Synopsis Available

Air And Water Pressure $28.28 No Synopsis Available

Air & Water Pressure $28.76 No Synopsis Available

A-619B 5-in-1 Air Pressure Massage Chair in $2149 The A-619B 5-in-1 Air Pressure Massage Chair is designed to provide anything from leisure to a physiotherapy massage for the back and legs This is greatly helpful for any working individual whether they spend the day sitting down or standing up By ma...

A-619R 5-in-1 Air Pressure Massage Chair in $2099 The A-619B 5-in-1 Air Pressure Massage Chair is designed to provide anything from leisure to a physiotherapy massage for the back and legs This is greatly helpful for any working individual whether they spend the day sitting down or standing up By ma...

AutoMeter Phantom Air Pressure Gauge 5720 $52.51 AutoMeter Performance Gauges in stock now! Read AutoMeter Phantom Air Pressure Gauge 5720 customer reviews. AutoAccessoriesGarage.com has the best selection of AutoMeter Gauges at the lowest prices around. AutoMeter Phantom Air Pressure Gauge 5720 are chosen by auto enthusiasts everywhere to personalize their vehicles. Autometer Phantom Series Gauges available now at AutoAccessoriesGarage.

AutoMeter Carbon Fiber Air Pressure Gauge 4720 $53.03 AutoMeter Performance Gauges in stock now! Read AutoMeter Carbon Fiber Air Pressure Gauge 4720 customer reviews. AutoAccessoriesGarage.com has the best selection of AutoMeter Gauges at the lowest prices around. AutoMeter Carbon Fiber Air Pressure Gauge 4720 are chosen by auto enthusiasts everywhere to personalize their vehicles. Autometer Carbon Fiber Series Gauge available now at AutoAccessoriesGarage.

AutoMeter Ultra-Lite Air Pressure Gauge 4320 $52.88 AutoMeter Performance Gauges in stock now! Read AutoMeter Ultra-Lite Air Pressure Gauge 4320 customer reviews. AutoAccessoriesGarage.com has the best selection of AutoMeter Gauges at the lowest prices around. AutoMeter Ultra-Lite Air Pressure Gauge 4320 are chosen by auto enthusiasts everywhere to personalize their vehicles. Autometer UltraLite Series Gauges available now at AutoAccessoriesGarage.

AutoMeter Sport-Comp Air Pressure Gauge 3320 $48.11 AutoMeter Performance Gauges in stock now! Read AutoMeter Sport-Comp Air Pressure Gauge 3320 customer reviews. AutoAccessoriesGarage.com has the best selection of AutoMeter Gauges at the lowest prices around. AutoMeter Sport-Comp Air Pressure Gauge 3320 are chosen by auto enthusiasts everywhere to personalize their vehicles. Autometer SportComp Series Gauges available now at AutoAccessoriesGarage.

AutoMeter Z-Series Air Pressure Gauge 2620 $59.4 AutoMeter Performance Gauges in stock now! Read AutoMeter Z-Series Air Pressure Gauge 2620 customer reviews. AutoAccessoriesGarage.com has the best selection of AutoMeter Gauges at the lowest prices around. AutoMeter Z-Series Air Pressure Gauge 2620 are chosen by auto enthusiasts everywhere to personalize their vehicles. Autometer ZSeries Gauges available now at AutoAccessoriesGarage.