Linear actuator assembly and system

A hydraulic system, comprising:

• a linear hydraulic actuator having first and second actuator ports;
• a first hydraulic pump assembly connected to the linear hydraulic actuator, the first pump assembly to provide hydraulic fluid to operate the linear hydraulic actuator, the first hydraulic pump assembly including,
• a first hydraulic pump having a first casing defining a first interior volume, the first casing having a first inlet port in fluid communication with the first interior volume, and a first outlet port in fluid communication with the first interior volume, the first hydraulic pump having at least one first fluid driver disposed inside the first interior volume, each first fluid driver having at least one of a variable-speed or a variable torque motor;
• and
• a first control valve assembly with a first control valve in fluid communication with the first outlet port;
• a second hydraulic pump assembly connected to the linear hydraulic actuator, the first pump assembly and the second pump assembly arranged in a parallel or series flow configuration to provide hydraulic fluid to operate the linear hydraulic actuator, the second hydraulic pump assembly including,
• a second hydraulic pump having a second casing defining a second interior volume, the second casing having a second inlet port in fluid communication with the second interior volume, and a second outlet port in fluid communication with the second interior volume, the second hydraulic pump having at least one second fluid driver disposed inside the second interior volume, each second fluid driver having at least one of a variable-speed or a variable torque motor;
• and
• a second control valve assembly with a second control valve in fluid communication with the second outlet port;
• and
• a controller that establishes at least one of a speed or a torque of at least one of the first or second hydraulic pumps so as to maintain at least one of a flow in the hydraulic system at a flow set point or a pressure in the hydraulic system at a pressure set point and concurrently establishes an opening of the respective at least one of the first or second control valves so as to maintain at least one of the flow in the hydraulic system at the flow set point or the pressure in the hydraulic system at the pressure set point,
• wherein, based on a mode of operation for the controller, the controller performs one of,
• controlling the at least one of the first or second hydraulic pumps to maintain the pressure to the pressure set point and the at least one of the first or second control valves to maintain the flow to the flow set point,
• controlling the at least one of the first or second hydraulic pumps to maintain the pressure to the pressure set point or the at least one of the first or second control valves to maintain the pressure to the pressure set point,
• controlling the at least one of the first or second hydraulic pumps to maintain the flow to the flow set point and the at least one of the first or second control valves to maintain the flow to the flow set point, or
• controlling the at least one of the first or second hydraulic pumps to maintain the flow to the flow set point and the at least one of the first or second control valves to maintain the pressure to the pressure set point.

A linear actuator system comprising:

• a linear actuator;
• at least one pump assembly connected to the linear actuator, the at least one pump assembly to provide fluid to operate the linear actuator, each pump assembly including,
• a pump with at least one fluid driver comprising a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from an inlet port of the pump to an outlet port of the pump and to the linear actuator, and
• a control valve in fluid communication with the pump and disposed on a downstream side of the outlet port;
• and
• a controller that establishes at least one of a speed or a torque of the at least one prime mover so as to maintain at least one of a flow in the linear actuator system at a flow set point or a pressure in the linear actuator system at a pressure set point and concurrently establishes an opening of the control valve so as to maintain at least one of the flow in the linear actuator system at the flow set point or the pressure in the linear actuator system at the pressure set point,
• wherein, based on a mode of operation for the controller, the controller performs one of,
• controlling the at least one prime mover to maintain the pressure to the pressure set point and the control valve to maintain the flow to the flow set point,
• controlling the at least one prime mover to maintain the pressure to the pressure set point and the control valve to maintain the pressure to the pressure set point,
• controlling the at least one prime mover to maintain the flow to the flow set point and the control valve to maintain the flow to the flow set point, or
• controlling the at least one prime mover to maintain the flow to the flow set point and the control valve to maintain the pressure to the pressure set point.