Hydraulic and Pneumatic Cylinders
SCI Sharp Controls



LeHigh Position Sensing Cylinders

Lehigh JHDA Series Linear Air Motors features the JHD heavy duty air cylinder with an air valve mounted to create a cylinder and valve designed as a unit. These units are also available for automatic operation: Automatic Return or Automatic Reciprocating.
JHDA Series Cylinder With Lehigh 2MA Series Slide Valve, Brass Tube & Standard Steel Construction

Lehigh Position Sensing Cylinders

Lehigh Fluid Power Position Sensing Cylinders

Lehigh Position Sensing Available on All Series Cylinders!
There are four main types of position sensing devices for pneumatic and hydraulic cylinders:

Tie rod mounted limit switches that are actuated by a magnetic piston
End-of-stroke proximity switches that are actuated by the cylinder cushion boss
Linear displacement transducer constructed as a probe inside the cylinder rod
Servo-type positioner for an air cylinder operating by force-balance

Tie-rod mount limit switches that are adjustable throughout the cylinder stroke length are commonly available on pneumatic cylinders. We also offer this on our pressure rated hydraulic cylinders!

This is possible because the tube material in this JHDH series is not steel. Never has been. For 60 years we have built our pneumatic and pressure rated hydraulic cylinders with tubes made of tempered brass. This material enables us to feature the same magnetic piston sensing option in hydraulics that is common in pneumatics.

This same limit switch option is also available on our line of all-stainless steel cylinders

High Pressure Hydraulic cylinders with tie rod mounted limit switches
Lehigh has the capability to offer tie rod mounted limit switches on high pressure hydraulic cylinders and LSSW stainless series cylinders. The advantage of tie rod mounted switches is the ability to sense piston position anywhere along the stroke. In the past, end-of-stroke piston sensing was the only option available. The switch senses a magnet in a groove on the piston through the tube wall. The cylinder tube and piston must be made of non-ferrous material. The switch offered is the Balluff BMF 21. This switch and its mounting bracket are made specifically for tie rod cylinders. The switch is available in PNP or NPN normally-open, 10-30 VDC.

This new switch option is available for cylinder bores 1 1/2” through 4”. The switches can be used with any standard catalog NFPA mounting option

Tie Rod Mounted Limit Switches

This series of compact reed and hall effect switches is designed to be rugged and cost effective to electrically sense cylinder stroke position. Mounting is accomplished by clamping the the switch to the cylinder tie rod with the self adjusting clamp that comes with the switch. A large number of custom circuits are featured to match your application requirements

Technical Information

Working temperature: -22F to 176F
Vibration Resistance: 10 to 55 Hz
Life Expectancy at Full Load: 10,000,000 cycles
Max Switch Current: .25 amp to 4 amp
Repeatability: .001″
Shock Resistance: 30g @11 ms
Operating time: OPERATE: 1.5 usec – .6msec / RELEASE: .5 usec – .05 msec
NEMA Rating: NEMA 6 with wire lead cables, style 0 – NEMA 4 with connectors, styles 1, 2, 3 and 5