An electro-hydraulic energy-saving beam type
oil pump for reusing the energy under the condition of power generation is provided, which comprises a frame, a drive, a beam, a polish rod, a pre-drive head and an auxiliary hydraulic energy regenerator comprising a hydraulic
system and an
electric control unit. The hydraulic
system comprises an auxiliary supporting truss, a
hydraulic pump, a
hydraulic cylinder, an accumulator, a hydraulic integration block, an auxiliary hydraulic
oil tank and a movably contacting mechanism that is located on the beam and transmits the displacement of the beam to the
piston rod of the
hydraulic cylinder; the movably contacting mechanism is connected respectively with the
piston rod and the auxiliary supporting truss; on the platform of the auxiliary supporting truss, the
hydraulic cylinder and the accumulator are arranged parallelly; the hydraulic cylinder is connected with the accumulator through the hydraulic integration block; the base of the auxiliary supporting truss is connected with the
hydraulic pump, which is respectively connected with the auxiliary
oil tank and the hydraulic integration block. For the invention, the
drive motor of the
oil pump can be standby in a negative-power area and can recycle and reuse the
residual energy of the
negative power, so as to save power and energy without changing the structure and operation principle of the former beam type
oil pump.