single acting a single acting cylinder develops thrust in one direction only the piston is usually...

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Single Acting A single acting cylinder develops thrust in one direction only The piston is usually returned by a spring, but can be returned by some external means as well(ex. vertical load) Cylinders and Actuators

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Single Acting• A single acting cylinder develops thrust in one direction only• The piston is usually returned by a spring, but can be returned by some external means as well(ex. vertical load)

Cylinders and Actuators

Single Acting• A single acting cylinder develops thrust in one direction only• The piston is usually returned by a spring, but can be returned by some external means as well(ex. vertical load)

Advantages• lower air consumption compared to double acting• 3 way valve needed instead of 4 way (lower cost)

Cylinders and Actuators

Single Acting• A single acting cylinder develops thrust in one direction only• The piston is usually returned by a spring, but can be returned by some external means as well(ex. vertical load)

Advantages• lower air consumption compared to double acting• 3 way valve needed instead of 4 way (lower cost)

Disadvantages• Reduction in piston thrust• Longer length body due to size of spring

Cylinders and Actuators

Single Acting Spring Return

Single Acting Spring Return

Rest state. No pressure applied.Cylinder is retracted.

Single Acting Spring Return

Rest state. No pressure applied.Cylinder is retracted.

Air pressure applied.Cylinder extends. Springis compressed.

Single Acting

Rest state. No pressure applied.Cylinder is retracted.

Air pressure applied.Cylinder extends. Springis compressed.

Air pressure exhausted. Cylinderretracts due to the force of the spring and is returned to rest state.

Spring Return

Single Acting

Rest state. No pressure applied.Cylinder is extended.

Spring Extend

Single Acting Spring Extend

Rest state. No pressure applied.Cylinder is extended.

Air pressure applied.Cylinder retracts. Springis compressed.

Single Acting Spring Extend

Rest state. No pressure applied.Cylinder is extended.

Air pressure applied.Cylinder retracts. Springis compressed.

Air pressure exhausted. Cylinder extends due to the force of the spring and is extended to rest state.

Thrust is developed in both extending and retracting directionsas air pressure is applied to the appropriate ports.

Double Acting Cylinders

Thrust is developed in both extending and retracting directions as air pressure is applied to the appropriate ports.

Advantages• More compact body when compared to single acting• Higher force with smaller bore size due to absence of spring

Double Acting Cylinders

Thrust is developed in both extending and retracting directions as air pressure is applied to the appropriate ports.

Advantages• More compact body when compared to single acting• Higher force with smaller bore size due to absence of spring

Disadvantages• Force on retraction(piston rod side) is different than the

extension due to the reduced surface area where the piston rod attaches to the piston

Double Acting Cylinders

A B

Cylinder is at rest when neitherport is energized.

Double Acting

A B

Cylinder is at rest when neitherport is energized.

When A is pressurizedthe piston extends outand B exhausts air.

Double Acting

A B

Cylinder is at rest when neitherport is energized.

When A is pressurizedthe piston extends outand B exhausts air.

When B is pressurized, the pistonretracts and A exhausts air. Thecylinder is now back to its originalstate.

Double Acting

• Tandem Type

1

Variations in Cylinders

Double Rod Type

2 3

Variations in Cylinders

Double Rod Type

• Tandem Type

1

Variations in Cylinders

Double Rod Type

2 3

Rodless cylinders can typically be installed in 1/2 the space of that of a standard cylinder. They are offered in much longer strokes and have higher side load capabilities.

Rodless Cylinders

Rodless cylinders can typically be installed in 1/2 the space of that of a standard cylinder. They are offered in much longer strokes and have higher side load capabilities.

Magnetically Coupled• The cylinder is coupled to the piston by magnetic force

requiring no physical attachment between the body

and the piston. Coupling permits smooth load transfer without allowing seal contamination.

Rodless Cylinders

Mechanically Coupled(Band Cylinder)• The cylinder is joined by a lip sealing mechanism suited for

very high loads while maintaining high accuracy. It has much higher side load capabilities but is not as totally leak free when compared to the magnetically coupled type.

• Commonly used in very precision type applications whichrequire compact and low profile dimensions.

Preciselymachined work mounting surfaces and parallel pistonguide rods ensure accurate and straight line movement.

Slide Units

• Commonly used in very precision type applications whichrequire compact and low profile dimensions.

Preciselymachined work mounting surfaces and parallel pistonguide rods ensure accurate and straight line movement.

• Either the body can be fixed and the rods with end barscan move or the end bars can be fixed and the body canmove

Slide Units

Designed to grip components using 2, 3, or 4 fingers

Air Chucks (Grippers)

Rack and Pinion Type• The output shaft has an integral pinion gear driven by a

a rack attached to a double piston. Standard angles of

rotation are 90° and 180°.

Rotary Actuators

Vane Type• Air pressure acts on a vane which is attached to the

output shaft. The vane is sealed against leakage bya lifted rubber seal or elastomer coating. Standardangles of rotation are 90°, 180° or 270°.

In certain applications, it is necessary to specify air cushionsor shock absorbers due to high speeds and considerableend of stroke forces.

Cushioning

In certain applications, it is necessary to specify air cushionsor shock absorbers due to high speeds and considerableend of stroke forces.

Rubber Cushions• Often used on smaller size bore and stroke cylinders to absorb

shock and prevent internal damage.

Cushioning

In certain applications, it is necessary to specify air cushionsor shock absorbers due to high speeds and considerableend of stroke forces.

Rubber Cushions• Often used on smaller size bore and stroke cylinders to absorb

shock and prevent internal damage.

Adjustable Air Cushions• Often used on larger size bore and stroke cylinders to decelerate

the piston over the last portion of the stroke. This cushion traps some of the exhausting air near the end of the strokebefore allowing it to bleed off slowly through an adjustableneedle valve.

Cushioning

Special “Sine” Cylinder Cushion• Rapid load transfer while allowing smooth acceleration

and deceleration of load which dramatically reducesshock/impact.

Special “Sine” Cylinder Cushion• Rapid load transfer while allowing smooth acceleration

and deceleration of load which dramatically reducesshock/impact.

Shock Absorbers• Used for very high speed and heavy load applications

to consistently decelerate loads without requiringadditional adjustment. Can withstand impacts of16 ft/second.

• Locking Cylinder- Allows for +/- .5mm incremental stopping accuracy

Cylinder Options

• Locking Cylinder- Allows for +/- .5mm incremental stopping accuracy

• Non-Rotating - Prevents piston rod and the load from rotating

Cylinder Options

• Locking Cylinder- Allows for +/- .5mm incremental stopping accuracy

• Non-Rotating - Prevents piston rod and the load from rotating

• Low Friction/Low Speed- Special internal seals and lubricants allows speeds

of 2mm per second

Cylinder Options

• Locking Cylinder- Allows for +/- .5mm incremental stopping accuracy

• Non-Rotating - Prevents piston rod and the load from rotating

• Low Friction/Low Speed- Special internal seals and lubricants allows speeds

of 2mm per second

• High Speed- Enlarged orifices are added to maximize speed

Cylinder Options

• Copper Free- all components can be electroless nickel plated for

copper free environments

• Copper Free- all components can be electroless nickel plated for

copper free environments

• High Temperature- up to 300°F applications

• Copper Free- all components can be electroless nickel plated for

copper free environments

• High Temperature- up to 300°F applications

• Low Temperature- down to -58 °F applications

• Copper Free- all components can be electroless nickel plated for

copper free environments

• High Temperature- up to 300°F applications

• Low Temperature- down to -58 °F applications

• Heavy Duty Rod- enlarged piston rod for heavy side load applications

• Copper Free- all components can be electroless nickel plated for

copper free environments

• High Temperature- up to 300°F applications

• Low Temperature- down to -58 °F applications

• Heavy Duty Rod- enlarged piston rod for heavy side load applications

• Adjustable Stroke- allows final extension or final retraction to be

adjusted

•Auto Switch Mount- allows stroke feedback/conformation to controller to

confirm work has been completed

•Auto Switch Mount- allows stroke feedback/conformation to controller to

confirm work has been completed

• High Magnetic Field Capability- special auto-switches and internal magnets allow

cylinder to be used in applications 2” awayfrom magnetic field displacing 20,000 Amps

Determining Which Cylinder Bore Size to Use

For a double acting cylinder:

Extending Stroke: Fe = ( / 4) * D² x PRetraction Stroke: Fr = ( / 4) * (D²-d²) x P

For a single acting cylinder:

Extending Stroke: Fes = ( / 4) * D² x P - Fs

D = Piston Diameter F = Forced = Piston Rod DiameterFs = Spring Force at the End of StrokeP = Gauge Pressure