公开(公告)号：US11318988B2

公开(公告)日：2022-05-03

申请号：US16247056

申请日：2019-01-14

申请人： Caterpillar Inc.

发明人： Edward W. Mate ,  John R. Connolly

IPC分类号： B62D5/06 ,  B62D5/087

摘要： An autonomous steering control unit for a hydraulic steering control system has a pilot selector valve, primary and secondary electro-hydraulic (EH) steering valves, and an output selector valve. In a primary autonomous steering mode, the primary EH steering valve operates to output pilot fluid from the pilot selector valve through the output selector valve to the steering control system to control steering of a work machine while the pilot selector valve and the output selector valve isolate the secondary EH steering valve from the steering control system. In a secondary autonomous steering mode, the secondary EH steering valve operates to output pilot fluid through the output selector valve to the steering control system while the primary EH steering valve is isolated from the steering control system. In alternative embodiments, a load sense selector valve alternately connects an dynamic load sense line to the operative steering valve.

公开(公告)号：US20200223476A1

公开(公告)日：2020-07-16

申请号：US16247056

申请日：2019-01-14

申请人： Caterpillar Inc.

发明人： Edward W. Mate ,  John R. Connolly

IPC分类号： B62D5/06 ,  B62D5/087 ,  G05D1/02

摘要： An autonomous steering control unit for a hydraulic steering control system has a pilot selector valve, primary and secondary electro-hydraulic (EH) steering valves, and an output selector valve. In a primary autonomous steering mode, the primary EH steering valve operates to output pilot fluid from the pilot selector valve through the output selector valve to the steering control system to control steering of a work machine while the pilot selector valve and the output selector valve isolate the secondary EH steering valve from the steering control system. In a secondary autonomous steering mode, the secondary EH steering valve operates to output pilot fluid through the output selector valve to the steering control system while the primary EH steering valve is isolated from the steering control system. In alternative embodiments, a load sense selector valve alternately connects an dynamic load sense line to the operative steering valve.

公开(公告)号：US20230017953A1

公开(公告)日：2023-01-19

申请号：US17379745

申请日：2021-07-19

申请人： Caterpillar Inc.

发明人： John R. Connolly ,  Aleem Junaidi ,  Jun Wen

IPC分类号： B60P1/16 ,  E02F9/22

摘要： A hoist valve assembly for a work machine cylinder includes a main control valve, a counterbalance valve and a counterbalance shutoff valve. A main control valve raise position connects a head end of the cylinder with a pressurized fluid source and a rod end of the cylinder to a low pressure reservoir to extend the cylinder. The counterbalance valve is between the rod end and the main control valve, is biased to a closed position and has an open position connecting the rod end to the low pressure reservoir. Rod end and head end pressure signals apply force to the counterbalance valve toward the open position. The counterbalance shutoff valve is positioned between the head end and the counterbalance valve, and has a normal position to apply the head end pressure signal to the counterbalance valve and a shutoff position that blocks the head end pressure signal from the counterbalance valve.