clippard schematic symbols

8/3/2019 Clippard Schematic Symbols

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Schematic symbols are used to identify andgraphically depict the function of fluid

power components.

Recognizing and understanding schematicsymbols will enable you to comprehend acircuits function.

Schematic drawings document themachine logic only and are never to be

used as a piping diagram.


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All pneumatic circuitsconsist of valves, actuators,

connecting lines and airpreparation equipment.

Valves control the direction and amount of flowwhile actuators are the work producers such ascylinders and rotary actuators.

Air preparation equipment conditions the air byproviding filtration, controlling pressure, andlubricating the valves and actuators.


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Directional Valves

Directional valves control the direction of flow

and are identified by the number of ways orports and their number of positions.

The number of ways defines valve function with away or port being either a line connection or anexhaust point.

Positions identify the number of discrete operatingpositions of the valve element - typically most air

valves are either 2 or 3 positions.


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Boxes are used to indicate the numberof valve positions. The number ofadjacent boxes indicates whether a

valve is a two or three position valve.

Two position valve

Three position valve


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Two way valve

Three way valve

Four way valve

Four way 5 ported valve


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Arrows are used to indicate the flowdirection

A tee indicates that a port or way is

blocked(closed or non passing).

Lines or connections are only drawn

to one valve position and are drawn to

the normal unactuated valve position.


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If the valve is a spring return the

spring position is usually the

normal position.

A way or port that is not connectedto a line outside the normal box

means that port is used for exhaust.


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Valve Actuation (shift)

Actuators are used to change valve positionsand can be mechanical, pneumatic pilot orelectric solenoid.

Mechanical actuators would include springs,push buttons, plungers, levers and cam rollers.

Pneumatic pilots are similar to cylinders and theychange valve position with a pressurized air

signal.


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Electric solenoids that change valve positionby directly moving the valve element are

called direct solenoid.

Electric solenoids that open small pilot valves

and allowing pressurized air to move thevalve element are called solenoid controlled

pilot operators.


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Valve Actuator Symbols

Spring Air Pilot

Push Button Solenoid

Plunger Solenoid Air Pilot

Lever

Cam Roller


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Two and three way valves with a springreturn are further identified as beingnormally closed (non passing) or normally

open (passing).

Three way valves can also be referred to

as a selector valve, diverter valve, and, asan AND and NOT.


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Complete Symbolswith Descriptions

Two position, two way,normally open plunger

operated valve with a springreturn.

Two position, two way, normallyclosed direct solenoid operated

valve with a spring return.


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Two position, three way,

normally closed air pilotoperated valve with spring

return.


normally open push button

operated valve with springreturn.

Two position, three way, lever

operated selector valve.


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Two position, three way, camroller operated diverter valvewith spring return.


normally closed air piloted valvewith spring return used asAND function.

Two position, three way,normally open air piloted valve

with spring return providingNOT function.


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Two position, four way,solenoid air pilot valve withspring return.

Two position, four way, airpilot valve with springreturn.


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Two position, 5 ported four way, double airpilot.

Three position, 5 ported four way, double

air pilot valve spring centered.


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Actuators

Actuators perform the work in Fluid PowerCircuits. They are used to clamp, move, rotate,

turn and position.

Cylinders are used for linear movements

while rotary actuators are used for limitedrotational applications and air motors are

used for continuous rotation.


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Actuators

Single acting cylinder,load return

Single acting cylinder, springreturn

Double acting cylinder


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Actuators

Rotary Actuator

Air Motor


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Lines

Intersecting Lines are shown tobe connected by using a dot.

Dashed lines are used to indicate apilot signal (not mandatory).

Loop jumpers are used to

indicate that lines cross and arenot connected.


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Air PreparationEquipment

Air Filter

Air Regulator

Lubricator


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Accessory Valves

Needle Valve

Check Valve

Flow Control Valve


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Accessory Valves

Shuttle Valve

Quick Exhaust valve

Pulse Valve (one shot)


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clippard schematic symbols

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