A POWER SYSTEM FOR A WORKING MACHINE AND CORRESPONDING OPERATION METHOD

    公开(公告)号:US20230135081A1

    公开(公告)日:2023-05-04

    申请号:US17923368

    申请日:2020-05-04

    IPC分类号: E02F9/20 E02F9/22

    摘要: A power system for a working machine, including a prime mover drivingly connectable to a main shaft; a planetary gear set including a rotatable first member drivingly connected to the main shaft, a rotatable second member and a rotatable third member for propulsion of the working machine; a hydraulic system including at least one hydraulic actuator for performing a working function of the working machine; an electric energy storage system; a first hydraulic machine mechanically coupled to the main shaft and hydraulically coupled to the hydraulic system; a first electric machine mechanically coupled to the main shaft; a second electric machine mechanically coupled to the rotatable second member, wherein the electric energy storage system is electrically connected to the first and second electric machines, and wherein the power system further includes a second hydraulic machine mechanically coupled to the rotatable second member and hydraulically coupled to the hydraulic system.

    Hydraulic Circuit for a Construction Machine

    公开(公告)号:US20230131384A1

    公开(公告)日:2023-04-27

    申请号:US17973789

    申请日:2022-10-26

    申请人: Caterpillar SARL

    摘要: Problem to be solved: To provide a hydraulic circuit for the construction machine which enables to use the relief valve of low capacity in the work tool circuit. Solution: The hydraulic circuit 2 for a construction machine has: a hydraulic pump 4 of variable capacity, a work tool 6 operated by hydraulic oil delivered by the hydraulic pump 4, a work tool operating device 10 to output a signal for operating the work tool 6, a control valve 14 allowing the hydraulic pump 4 to supply the hydraulic oil to the work tool 6 based on the signal output from the work tool operating device 10, a tool's relief valve 44 to release the hydraulic oil flowing between the control valve 14 and the work tool 6, a pressure sensor 46 to detect a pressure of hydraulic oil flowing into the work tool 6, and a controller 48 to reduce a delivery rate from the hydraulic pump 4 when the pressure detected by the pressure sensor 46 exceeds a predetermined value.

    Hydraulic system and a method for controlling a hydraulic system of a working machine

    公开(公告)号:US11635095B2

    公开(公告)日:2023-04-25

    申请号:US17606459

    申请日:2019-04-26

    摘要: A hydraulic system for a working machine includes a first electric machine connected to a first hydraulic machine; a second electric machine connected to a second hydraulic machine, an output side of the second hydraulic machine being connected to an input side of the first hydraulic machine; at least one hydraulic consumer hydraulically coupled to an output side of the first hydraulic machine via a supply line and configured to be powered by the first hydraulic machine; and a valve arrangement arranged between the hydraulic consumer and the first and second hydraulic machines, wherein the valve arrangement is configured to control a return flow of hydraulic fluid from the hydraulic consumer to either the input side of the first hydraulic machine or an input side of the second hydraulic machine based on a requested output pressure from the first hydraulic machine.

    HYDRAULIC CONTROL SYSTEM FOR A WORKING MACHINE

    公开(公告)号:US20230119892A1

    公开(公告)日:2023-04-20

    申请号:US17792446

    申请日:2021-01-08

    申请人: Caterpillar SARL

    摘要: To enable to arbitrarily change a hydraulic pump which supplies pressure oil to a hydraulic actuator at first in a hydraulic control system equipped with the hydraulic actuator using both first and second hydraulic pumps as a pressure oil source. An operation means is installed which can arbitrarily change working order of the first flow rate control valves for boom and stick for controlling the supply flow rate from first hydraulic pump to boom cylinder and stick cylinder and second flow rate control valves for boom and stick for controlling the supply flow rate from second hydraulic pump to boom cylinder and stick cylinder.

    Hydraulic control circuit for a construction machine

    公开(公告)号:US11629479B2

    公开(公告)日:2023-04-18

    申请号:US17413831

    申请日:2019-12-11

    申请人: Caterpillar SARL

    摘要: To make it possible to control supply, discharge, and recycled flow rates independently of each other for the stick cylinder in a construction machine comprising first and second stick spool valves respectively connected to first and second hydraulic pumps. [Solution] A poppet valve is provided at upstream side of the first stick spool valve for controlling a supply flow rate from first hydraulic pump, the first stick spool valve is configured to supply hydraulic flow from the poppet valve to the stick cylinder without restricting the flow, and when the stick cylinder is extended, the poppet valve is configured to control supply flow rate from the first hydraulic pump to head side oil chamber, the first stick spool valve is configured to control recycled flow rate from a rod side oil chamber to the head side oil chamber, and the second stick spool valve is configured to control the supply flow rate from second hydraulic pump to head side oil chamber and the discharge flow rate from the rod side oil chamber to an oil tank.

    Shovel having boom raising assisting function using attachment information

    公开(公告)号:US11619030B2

    公开(公告)日:2023-04-04

    申请号:US16558708

    申请日:2019-09-03

    发明人: Youji Misaki

    摘要: A shovel includes a lower traveling body, an upper turning body turnably mounted on the lower traveling body, a cab mounted on the upper turning body, an attachment including a boom attached to the upper turning body, a boom cylinder configured to drive the boom, a control device configured to control hydraulic oil flowable into the boom cylinder, and an information obtaining device configured to obtain information on the attachment. The control device is configured to increase the pressure of hydraulic oil flowable into the boom cylinder in accordance with the information on the attachment before a boom raising operation is performed.

    SYSTEM AND METHOD FOR CONTROLLING PUMP OPERATING SPEED RANGE OF AN ELECTRIC WORK VEHICLE BASED ON HYDRAULIC FLUID PRESSURE

    公开(公告)号:US20230098498A1

    公开(公告)日:2023-03-30

    申请号:US17802732

    申请日:2021-02-25

    IPC分类号: E02F9/22

    摘要: An electric work vehicle a pump configured to supply hydraulic fluid to a component of the electric work vehicle. Moreover, the electric work vehicle includes a sensor configured to capture data indicative of a pressure of the hydraulic fluid and a controller communicatively coupled to the sensor. As such, the controller is configured to monitor the pressure of the hydraulic fluid relative to a predetermined threshold pressure value based on the data captured the sensor. In addition, the controller is configured to control the operation of the pump such that the pump is switched from a first operating speed range to a second operating speed range when the monitored pressure of the hydraulic fluid falls below the predetermined threshold pressure value.

    CONSTRUCTION MACHINE
    8.
    发明申请

    公开(公告)号:US20230098211A1

    公开(公告)日:2023-03-30

    申请号:US17908985

    申请日:2021-09-16

    发明人: Kazuyuki ITO

    摘要: Provided is a construction machine capable of improving the accuracy of load weight measurement without reducing the operational efficiency of a working device. A wheel loader 1 as a construction machine comprises a hydraulically driven working device 2 and a controller 5,5A for measuring the weight of a load, wherein the wheel loader 1 includes a changeover switch 121 as a changeover device for switching whether to measure the weight of the load, and in a case where an attitude of the working device 2 satisfies a predetermined load measurement condition, the changeover switch 121 is valid, and pistons 222, 242 are positioned in a first area provided on one end side or in a second area provided on the other end side, the controller 5, 5A limits the command current to be output to lift arm solenoid proportional valves 45 and the bucket solenoid proportional valves 46.

    Loading machine with selectable performance modes

    公开(公告)号:US11608614B2

    公开(公告)日:2023-03-21

    申请号:US17132533

    申请日:2020-12-23

    申请人: Caterpillar Inc.

    IPC分类号: E02F9/22 E02F9/20

    摘要: A loading machine for loading, hauling, and dumping material about a worksite includes a lifting implement pivotally joined to a machine frame to articulate with respect to a work surface. A lift sensor is operatively configured to measure vertical articulation of the lifting mechanism. An electronic controller communicating with the lift sensor can be programmed to operate the loading machine in one of a rated performance mode and a limited performance mode depending upon the vertical articulation of the lifting implement with respect to the work surface.

    Hydraulic unit
    10.
    发明授权

    公开(公告)号:US11608612B2

    公开(公告)日:2023-03-21

    申请号:US17760718

    申请日:2020-09-02

    摘要: A hydraulic unit includes a hydraulic circuit fluidly connected to a hydraulic actuator, and a control device to control the hydraulic circuit. The hydraulic circuit includes a hydraulic oil tank, a hydraulic pump that supplies the hydraulic oil to the hydraulic actuator from the hydraulic oil tank, a discharge flow path fluidly connecting a discharge side of the hydraulic pump to the hydraulic actuator, a valve that blocks a flow of the hydraulic oil in the discharge flow path, and a pressure sensor that detects a pressure of the hydraulic oil the discharge flow path. In a pressure holding state, when a rotational frequency of the hydraulic pump exceeds a predetermined first determination rotational frequency or when a discharge flow rate of the hydraulic pump exceeds a predetermined first determination discharge flow rate, the control device determines that the hydraulic circuit is abnormal.