Hydraulic Cylinders with Magnetostrictive Transducers

Hydraulic cylinders are an essential component for many types of equipment, and they can be classified according to several criteria. However, this article is not about the types and application of hydraulic cylinders – it covers the options and devices for the hydraulic actuators as well as the advantages that can be taken of them.

Technological progress doesn’t stand still, and every year we discover new opportunities and find the solutions for non-standard situations. This statement is true for hydraulics, too. For example, tracking the linear position of a hydraulic cylinder has been made possible relatively recently thanks to such devices as position feedback sensors, or magnetostrictive transducers.

Hydraulic Cylinders with Magnetostrictive Transducers

Magnetostrictive transducers have been widely applied since it enables to automate some of the production processes. Concerning hydraulic cylinders, these transducers are installed into the rod end of the cylinder for measuring the exact position of the piston.

How does it work in a hydraulic cylinder?

The operating principle of the feedback sensor is based on magnetostriction, a physical phenomenon that is observed in ferromagnetic materials (iron, cobalt, nickel and most of their alloys). The basic components of a magnetostrictive transducer include the waveguide in a protective cover, electronic housing and a position magnet that is, in our case, connected to the piston. The waveguide is placed into a hydraulic cylinder, and the magnet moves along it. To register the position of a moving magnet as accurately as possible, the sensor only needs to measure the time of signal transmission from sending a current pulse to its return in a deformed form. Thus, you can get the reliable value of the object coordinates and the speed of its movement. Once this information is read, it is transmitted to the hardware controller.

Why use such a transducer?

The magnetostrictive sensor can be installed when there is a need to get accurate measurement results. Besides, it has the additional advantage of having no rubbing units, and this eliminates wear on moving parts.

Hydraulic Cylinders with Magnetostrictive Transducers

Let’s consider a real situation. On the veneer production line, high cutting accuracy is required, since the thickness of this product must be uniform. The material is manufactured using a special machine with a knife. How this machine works: the knife comes into contact with the annual rings of the tree, and then we get a piece of veneer. But for this contact to happen, we need a mechanism that will create movement. It is obvious that doing this manually, firstly, is very long, and secondly, it does not guarantee the accuracy of execution. This is why this process (ideally) should be automated. And this is there where we might need a feedback sensor that will be installed in the hydraulic cylinder controlling the knife movement. The transducer will convey the information about the cylinder position to a special device; it will also regulate the time and the moment when the cylinder should be moving to control the knife. Thus, accuracy and precision are ensured.

At HydroCube, we design and produce bespoke hydraulic cylinders of any complexity according to the customers’ specifications. The use of high-quality materials, strict control over each stage of the production and many years of experience of our employees allow us to provide services at the best possible level and produce reliable hydraulic equipment with impeccable design. Before being sent to the customer, the manufactured equipment undergoes tests on a modern test bench. To acquire hydraulic cylinders at HydroCube means to choose truly good equipment with long service life and to eliminate production stoppage.