Hydraulically coupled multi-variator actuator

A continuously variable transmission comprising:

• a mechanical transmission having an input, the mechanical transmission having;
• a planetary gear arrangement;
• a hydrostatic transmission having an input and an output, the output of the hydrostatic transmission being connected to the planetary gear arrangement, the hydrostatic transmission having;
• a first variator having a hydraulic pump and a hydraulic motor;
• a second variator having a hydraulic pump and a hydraulic motor;
• a first actuator linked to the hydraulic pump of the first variator and configured to control a displacement of the hydraulic pump of the first variator;
• a second actuator linked to the hydraulic pump of the second variator and configured to control a displacement of the hydraulic pump of the second variator;
• a hydraulic link connecting the first actuator and the second actuator and configured to facilitate a coordinated operation of the first actuator and the second actuator;
• a valve disposed in fluid communication with the hydraulic link connecting the first actuator and the second actuator;
• and
• a controller connected to the valve and configured to control an operation of the valve to regulate hydraulic flow in the hydraulic link based on a difference in a pump loop pressure of the first hydraulic variator and a pump loop pressure of the second hydraulic variator.

A method of operating a multi-variator system, the method comprising:

• hydraulically connecting, via a hydraulic link, a first actuator configured to control a first hydraulic pump of a first variator and a second actuator configured to control a second hydraulic pump of a second variator, wherein the hydraulically connecting facilitates a coordinated operation of the first actuator and the second actuator;
• determining a difference in a pump loop pressure of the first variator and a pump loop pressure of the second variator;
• and
• regulating, by a valve disposed in fluid communication with the hydraulic link, a hydraulic flow in the hydraulic link to further facilitate the coordinated operation of the first actuator and the second actuator to equalize the pump loop pressure of the first variator and the pump loop pressure of the second variator.