US 12,313,099 B2
Hydraulic system with a functional safety feature for demolition robots
Masoud Varshosaz, Huskvarna (SE)
Assigned to HUSQVARNA AB, Huskvarna (SE)
Filed by HUSQVARNA AB, Huskvarna (SE)
Filed on May 2, 2024, as Appl. No. 18/653,279.
Claims priority of application No. 2350540-7 (SE), filed on May 4, 2023.
Prior Publication US 2024/0369083 A1, Nov. 7, 2024
Int. Cl. F15B 20/00 (2006.01); E02F 9/22 (2006.01); F15B 11/16 (2006.01); F15B 19/00 (2006.01)
CPC F15B 20/00 (2013.01) [E02F 9/2221 (2013.01); E02F 9/2228 (2013.01); E02F 9/226 (2013.01); F15B 11/161 (2013.01); F15B 11/165 (2013.01); F15B 20/002 (2013.01); F15B 20/008 (2013.01); E02F 9/2296 (2013.01); F15B 19/005 (2013.01); F15B 2211/20515 (2013.01); F15B 2211/20546 (2013.01); F15B 2211/6051 (2013.01); F15B 2211/6313 (2013.01); F15B 2211/857 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A hydraulic system for controlling one or more movable members on construction equipment, wherein the hydraulic system is configurable in a safe mode of operation associated with stationarity of at least one movable member, the system comprising:
a load sensing, LS, circuit connected to one or more hydraulic valves of the hydraulic system, wherein a hydraulic pump controller is arranged to control an operation of a hydraulic pump of the hydraulic system based on a pressure feedback signal from the LS circuit,
a first hydraulic pressure sensor arranged to sense a first LS pressure in a first LS circuit part of the LS circuit, wherein the first LS circuit part is connected to the one or more hydraulic valves arranged to operate the at least one movable member associated with stationarity when the hydraulic system is configured in the safe mode of operation, and
a control unit arranged to monitor the sensed first LS pressure,
wherein the control unit is arranged to compare the first LS pressure to a predetermined acceptance criterion associated with stationarity of the at least one movable member, and
wherein the control unit is arranged to trigger a safety-related action by the hydraulic system responsive to the hydraulic system being configured in the safe mode of operation and the first LS pressure not satisfying the acceptance criterion.
 
17. A control unit arranged to control a hydraulic system on construction equipment comprising one or more movable members, wherein the control unit is configured to operate the construction equipment in a safe mode of operation,
wherein the hydraulic system comprises a load sensing, LS, circuit connected to one or more hydraulic valves of the hydraulic system, wherein a hydraulic pump controller is arranged to control an operation of a hydraulic pump of the hydraulic system based on a pressure feedback signal from the LS circuit,
the control unit comprising processing circuitry operable to:
obtain a first LS pressure from a first hydraulic pressure sensor arranged to sense pressure in a first LS circuit part of the LS circuit, wherein the first LS circuit part is connected to one or more hydraulic valves arranged to operate one or more of the movable members,
monitor the sensed first LS pressure,
compare the first LS pressure to a predetermined acceptance criterion associated with stationarity of the one or more movable members, and
trigger a safety-related action by the hydraulic system in response to the hydraulic system being configured in the safe mode of operation and the first LS pressure not satisfying the acceptance criterion.
 
18. A computer-implemented method for controlling a hydraulic system on construction equipment comprising one or more movable members, wherein the hydraulic system is configurable in a safe mode of operation associated with stationarity of at least one of the one or more movable members,
wherein the hydraulic system comprises a load sensing, LS, circuit connected to one or more hydraulic valves of the hydraulic system, wherein a hydraulic pump controller is arranged to control an operation of a hydraulic pump of the hydraulic system based on a pressure feedback signal from the LS circuit,
the computer implemented method comprising:
obtaining a first LS pressure from a first hydraulic pressure sensor arranged to sense pressure in a first LS circuit part of the LS circuit, wherein the first LS circuit part is connected to one or more hydraulic valves arranged to operate one or more of the movable members,
monitoring the sensed first LS pressure,
comparing the first LS pressure to a predetermined acceptance criterion associated with stationarity of the one or more movable members, and
triggering a safety-related action by the hydraulic system in response to the hydraulic system being configured in the safe mode of operation and the first LS pressure not satisfying the acceptance criterion.