TSM 363: Fluid Power Systems

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TSM 363 Fluid Power Systems

• Linear Rotary Hydraulic Actuators

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Linear Actuators in Hydraulic Systems
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Single-Rod Cylinder
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Force Speed Delivered by Cylinders
Rod-end
Cap-end
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Typical Applications of Cylinders
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Some Common Cylinder Applications
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Discussion on a Parallel Application

• Two loaded cylinders are placed in a parallel
  circuit with a pump that delivers 60 L/min and a
  pressure relief that cracks at 15 MPa. Describe
  the operation of the circuit when energized.

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What Happened in the System
The cylinder with the 30 kN load will extend
first, followed by the cylinder with the 40kN
load in sequence. The time of the sequence is
computed from the stroke and flow rate.
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Other Cylinder TypesDouble-Acting Cylinder
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Other Cylinder Types Ram Cylinder
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Cylinder Cushion
cushion velocity
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Rotary Actuators
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Hydraulic Motors and Key Parameters
Uni-directional fixed- or variable-displacement
motor
Bi-directional fixed- or variable-displacement
motor
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High Speed Motors Vane Types
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High Speed Motors Gear Types
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High Speed Motors Gerotor Types
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High Speed Motors Axial Piston Types
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Low Speed Motors Radial Piston Types
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Low Speed Motors Rolling Vane Types
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Oscillating Type Motors
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Torque, Volumetric, Power Efficiencies
Efficiency ()
Each pump has an operating range with acceptable
efficiency.
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Lecture Summary

• Discussed the basic concepts of hydraulic
  actuators
• Linear (cylinders)
• Rotary (motors)
• Introduced key parameters
• Speed and force
• Rotating speed and torque
• Efficiencies