Ruggeri, M., Massarotti, G., Marani, P., and Ferraresi, C., "New Matrix Pump Switching Valve," SAE Technical Paper 2015-01-2855, 2015, doi:10.4271/2015-01-2855.
Losses reduction and oil flow optimization management in construction machines and, in general, in heavy duty vehicles are two of the most challenging missions of today fluid power research. One of the most promising ideas is to implement multiple hydraulic power sources but this requires a flexible pump switch system; in fact, depending on flow request and machine mode, one or more pumps can be switched to serve each actuator. To put into practice these concepts it is necessary to in-depth design the distribution system, through which hydrostatic transmissions supply the different loads. The new component here presented realizes the pump switch management, creating a matrix framework of the hydraulic flow connections. Putting this concept it into practice the new architecture is able to connect alternatively a pump to one actuator at a time providing also for cross connections, enabling different sources flow summation. The matrix for oil flow management is aimed at offering a flexible, safe and scalable solution, and it can be replicated to form a stack, providing a physical matrix of rows and columns for oil distribution to actuators. The basic rule for the matrix management is that only a single actuator can be fed by each pump, but more connections can be activated for an actuator, offering a flexible flow management and enabling a new approach to pump sizing studies on machines. The component is a rotating distributor with a safety spool, that can connect discharge and return ports of one pump to the A and B port of each actuator, moving the safety spool only when the rotary distributor is coupled with the desired actuator. Both closed center and open center configurations are possible, as well as regenerative systems can be implemented.The paper will focus mainly on design concept and architectural alternatives and potential benefits of the implementation of the concept on state of art architectures from the functional capability point of view.