公开(公告)号：US11536265B2

公开(公告)日：2022-12-27

申请号：US17089095

申请日：2020-11-04

Applicant: Danfoss Power Solutions II Technology A/S

Inventor： Don Rulon Draper ,  Robert Leslie Isaacs

IPC: F04B49/12 ,  F04B1/324 ,  F04B49/00 ,  F04B49/22 ,  F04B49/08 ,  F04B1/2078 ,  F04B1/2085 ,  F04B1/124 ,  F04B1/146 ,  F04B1/295

Abstract: The present invention relates to a hydraulic pump system including a variable displacement pump that generates an outlet pressure. The hydraulic pump system also includes a control system that decreases a displacement volume of the variable displacement pump in response to an increase in the outlet pressure and increases a displacement volume of the variable displacement pump in response to a decrease in the outlet pressure.

公开(公告)号：US11378068B2

公开(公告)日：2022-07-05

申请号：US16927316

申请日：2020-07-13

Applicant: Danfoss Power Solutions II Technology A/S

Inventor： Anil Balasaheb Kharpas ,  Avinash Dadaso Patil ,  Sanjay Dhondappa Mali ,  Amit Ranjit Panchal ,  Robert Leslie Isaacs

IPC: F04B1/324 ,  F15B13/16 ,  F15B13/044 ,  G05D16/20 ,  F04B49/00 ,  F15B13/04 ,  F04B49/08 ,  F15B13/02

Abstract: A pump control assembly for controlling a variable displacement hydraulic pump includes a spool mounted within a valve block. The spool is configured to move between a first and a second position within the valve block so as to selectively control the displacement of the attached pump. The pump control assembly further includes first and second chambers that each apply a force to opposite ends of the spool. The first chamber is positioned at a first end of the spool in fluid communication with a pump output port. The second chamber is positioned at a second end of the spool and in fluid communication with a hydraulic tank port and a proportional pressure reducing valve. The second chamber also includes a piston and first and second springs positioned on either side of the piston. The proportional pressure reducing valve provides a regulated pressure to a first side of the piston along with the first spring, and the hydraulic tank port provides a tank pressure on the opposite side of the piston along with the second spring. The pump control assembly also includes a stop structure having a positive stop that limits movement of the piston in a direction toward the first chamber.