Rotary Controls Bring Revolution in Size and Robustness to Servo Valves
By harnessing the power of additive manufacturing and other 21st century technologies, Domin have taken a largely common design (the linear servo valve) and have created a unique interpretation that squeezes out every possible drop of performance.
We then took the manual for a ‘traditional’ hydraulic servo valve and threw it out the window. Domin’s new creation has now opened the flood gates on what is achievable in fluid power.
Introducing, the new rotary-controlled servo valve and all the possibilities that come with it!
Channelling the direction of fluid is the primary function of a hydraulic servo valve. Traditionally, this has been done through the linear movement of a spool. This type of fluid control has dominated the hydraulics industry for many years and is very successful.
We have our own linear designed servo valve, the S6 Pro.
One of the major differences between the S6 Pro and a competitor’s valve is the way the galleries deliver fluid to the bore. The S6 Pro has spiralling galleries that inject fluid around the entire circumference of the bore. This clever design has increased flow to the service ports and reduced the space in which it does so. Architecture like this is only possible due to Domin’s commitment to additive manufacturing.
Our designers are always looking for innovative ways to direct hydraulic fluid. We look for a path that has the least resistance and delivers the most amount of flow, giving the unit the highest possible efficiency. Fluid travels best in curves and additive manufacturing gives access to a 3D world that engineers can now manipulate to their advantage.
Throwing out the manual to revolutionise the design.
The Next Chapter
Rotary to Rotary Design:
Continuing from the success of the S6 Pro, the team here have taken our knowledge and implemented a completely new approach to fluid control. Moving away from the old linear spool movement, we have now introduced a brand-new world leading design.
The S4 Pro combines both rotor and spool into one single component. All four flow paths are then intertwined around a central bore and the motor directly controls a spool. This approach mitigates the need for cam linkages and offers a more robust and compact form of control. The rotor/spool is then driven in a rotational motion allowing fluid to flow through precisely placed grooves in the spool. These grooves govern the amount of flow to each port and channel the fluid to the desired gallery.
Restructuring the design has increased performance and reduced the step response time to value of 3ms (100% amplitude), that’s 75% faster than the MOOG D633. The faster response time and high accuracy in control means that the product can confidently provide a solution to the increasing demands of today’s digitally controlled actuators. Redesigning the traditional servo valve and miniaturising the unit has had a huge impact on its robustness and space saving ability. Reducing the number of components and condensing the size and weight has made this product an attractive choice for weight saving industries such as automotive, aerospace and animatronics.
The patented technology is now revolutionising the way hydraulic systems operate. We now have the ability to build from the foundations of the S4 Pro and create even more complicated systems. Combining this technology with active suspension units and digital fluid control systems is now the focus for Domin.
Rotary design is now completely reforming how integrated hydraulic systems are controlled.
A New World
The future for hydraulics and where Domin makes its most significant impact, is with integrated systems. Combining motors, pumps, valves, and actuators into one compact unit and driving the system by wire is the future for hydraulics. We are currently developing a multitude of integrated systems that have only been made possible due to the success of the S4 Pro rotary design.
One project in particular has accelerated the rotary design to ambitious levels and could change the way the next generation of vehicles are driven. Creating a complicated network of fluid galleries, the FAST project (full active suspension technology) has effectively integrated seven servo valves into one active suspension unit, with only one integral spool controlling all seven valves. One sweep of the 150° angle range and an array of different galleries will open and close simultaneously. Along with the multiple galleries, the system includes four different accumulators that are designed to store hydraulic energy instead of dumping waste fluid back to a return tank.
Most hydraulic systems are highly inefficient and waste energy either through excessive pump speed or internal leakage. The FAST unit can recycle fluid by storing energy in accumulators and using it when it is needed. It can even reuse its own internal leakage. Rotary control has forever changed the way fluid is manipulated and it will bring revolution to how the world optimises hydraulic energy use, helping us, together, to save 1 billion tons of CO2.