公开(公告)号：US20210277920A1

公开(公告)日：2021-09-09

申请号：US16810068

申请日：2020-03-05

Applicant: HONEYWELL INTERNATIONAL INC.

Inventor： Paul W. Futa ,  Matthew Arend ,  Charles Walejewski ,  Calin Bondariu

IPC: F15B20/00 ,  F15B15/18

Abstract: A system uses a two-stage, four-way electrohydraulic servo valve that includes an additional control port that commands a fail-fixed valve to lock the position of a device in the last commanded position. The additional port is modulated by an existing land on the EHSV valve element, adding little to no complexity. Major technical benefits of the disclosed system are that it adds little to no cost, complexity, size, or weight the device being controlled. The disclosed configuration allows for the use of a relatively small and simple fail-fixed valve, and the control ports on the controlled device keep “drift” to a minimum, when transitioning between normal operating mode and fail-fixed operating mode.

公开(公告)号：US11242875B2

公开(公告)日：2022-02-08

申请号：US16810068

申请日：2020-03-05

Applicant: HONEYWELL INTERNATIONAL INC.

Inventor： Paul W. Futa ,  Matthew Arend ,  Charles Walejewski ,  Calin Bondariu

IPC: F15B20/00 ,  F15B13/043

Abstract: A system uses a two-stage electrohydraulic servo valve that includes an additional control port that commands a fail-fixed valve to lock the position of a device in the last commanded position. The additional port is modulated by an existing land on the EHSV valve element, adding little to no complexity. Major technical benefits of the disclosed system are that it adds little to no cost, complexity, size, or weight the device being controlled. The disclosed configuration allows for the use of a relatively small and simple fail-fixed valve, and the control ports on the controlled device keep “drift” to a minimum, when transitioning between normal operating mode and fail-fixed operating mode.