A fluid pressure unit and a control method for the fluid pressure unit. The fluid pressure unit (A) comprises a hydraulic pump driven by a motor (2) and a hydraulic cylinder (3) driving a chuck. To simultaneously realize the high-speed operation of the cylinder (3) and a reduction in the surge pressure of the cylinder (3), the fixed displacement type hydraulic pump is combined with the variable speed motor (2) driving the pump. When the cylinder (3) is driven to drive the chuck, a teaching operation is performed to obtain the operating stroke of the cylinder (3) based on the rotational speed of the motor (2), and the motor (2) is rotated at a high rotational speed for operation until the cylinder (3) reaches a pre-set deceleration start position immediately before the end of the operation in the obtained operating stroke and, after the cylinder (3) reaches the deceleration start position, rotated at a low rotational speed for deceleration until the operation is terminated to softly bring the chuck into contact with a work.
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