US20140330490A1 - Work Vehicle - Google Patents

Work Vehicle Download PDF

Info

Publication number
US20140330490A1
US20140330490A1 US14/360,963 US201214360963A US2014330490A1 US 20140330490 A1 US20140330490 A1 US 20140330490A1 US 201214360963 A US201214360963 A US 201214360963A US 2014330490 A1 US2014330490 A1 US 2014330490A1
Authority
US
United States
Prior art keywords
height position
work
bucket
height
work tool
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US14/360,963
Other languages
English (en)
Inventor
Isamu Aoki
Koji Hyodo
Tetsuji Tanaka
Keigo Kikuchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Construction Machinery Co Ltd
Original Assignee
Hitachi Construction Machinery Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Construction Machinery Co Ltd filed Critical Hitachi Construction Machinery Co Ltd
Assigned to HITACHI CONSTRUCTION MACHINERY CO., LTD. reassignment HITACHI CONSTRUCTION MACHINERY CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KIKUCHI, KEIGO, AOKI, ISAMU, HYODO, KOJI, TANAKA, TETSUJI
Publication of US20140330490A1 publication Critical patent/US20140330490A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F3/00Dredgers; Soil-shifting machines
    • E02F3/04Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/28Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
    • E02F3/36Component parts
    • E02F3/42Drives for dippers, buckets, dipper-arms or bucket-arms
    • E02F3/43Control of dipper or bucket position; Control of sequence of drive operations
    • E02F3/431Control of dipper or bucket position; Control of sequence of drive operations for bucket-arms, front-end loaders, dumpers or the like
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/2058Electric or electro-mechanical or mechanical control devices of vehicle sub-units
    • E02F9/2079Control of mechanical transmission
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2203Arrangements for controlling the attitude of actuators, e.g. speed, floating function
    • E02F9/2207Arrangements for controlling the attitude of actuators, e.g. speed, floating function for reducing or compensating oscillations
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2217Hydraulic or pneumatic drives with energy recovery arrangements, e.g. using accumulators, flywheels
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2253Controlling the travelling speed of vehicles, e.g. adjusting travelling speed according to implement loads, control of hydrostatic transmission
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/26Indicating devices
    • E02F9/264Sensors and their calibration for indicating the position of the work tool
    • E02F9/265Sensors and their calibration for indicating the position of the work tool with follow-up actions (e.g. control signals sent to actuate the work tool)

Definitions

  • the present invention relates to a work vehicle such as a wheel loader, and particularly relates to a work vehicle provided with a ride control device or a transmission control device in which the height position of a work tool such as a bucket is used as a control parameter.
  • the ride control device is a device in which a hydraulic pressure accumulator is connected through a control valve to a lift cylinder hydraulic circuit which supplies hydraulic oil to a lift cylinder for driving a work tool.
  • the hydraulic oil is allowed to circulate between the lift cylinder and the hydraulic pressure accumulator when the control valve is opened.
  • the fluctuation of bottom pressure generated in the lift cylinder due to the vertical motion of the work vehicle which is travelling can be absorbed to the hydraulic pressure accumulator so as to reduce the impact acting on the vehicle body.
  • the control valve is fundamentally changed over by manual operation performed on a ride control switch by an operator.
  • the control valve may be opened and closed in a state which is not intended by the operator.
  • a sense of discomfort or a sense of insecurity in operation may be easily given to the operator.
  • description will be made by way of example in the case where in which a bucket is provided as a work tool for performing excavation work, hauling work and loading work onto a dump truck or the like.
  • the control valve is automatically changed over from the closed state to the open state in spite of the excavation work.
  • the force acting on the bucket escapes to the hydraulic pressure accumulator through the lift cylinder due to the damper effect of the hydraulic pressure accumulator, so as to give the operator a sense of discomfort as if the start timing of excavation has been delayed.
  • the control valve is automatically changed over from the closed state to the open state.
  • the oscillation of the bucket increases due to the damper effect of the hydraulic pressure accumulator, so as to give a needless sense of insecurity to the operator.
  • the applicant of the present application has already made a proposal in which a position of excavation, a position of hauling and a position of loading are set in a controller in advance, and a control valve is kept in a closed state in spite of a vehicle speed not lower than a set speed when a bucket is in a position not higher than the set position of excavation or not lower than the set position of loading (Japanese Patent Application No. 2011-56644).
  • Japanese Patent Application No. 2011-56644 Japanese Patent Application No. 2011-56644.
  • the bucket can be prevented from oscillating during excavation work or during loading work, so that the sense of discomfort or the sense of insecurity can be removed from the operator.
  • a work vehicle such as a wheel loader is also mounted with a transmission control device which automatically changes a speed stage of a transmission when the vehicle speed reaches a set speed.
  • shift-up operation may be performed against the operator's intention to accelerate the work vehicle when the vehicle speed is higher than the set speed.
  • the work efficiency may deteriorate instead.
  • the following work is performed when soil etc. fully loaded on the bucket is loaded onto a dump truck. That is, the work vehicle is moved forward from the position of excavation toward the stop position of the dump truck.
  • the amount of accelerator pedal depression is reduced to lower the vehicle speed.
  • the bucket is lifted up to the loading height onto the dump truck while the work vehicle is moved forward due to an inertia force.
  • the work vehicle is stopped in the loading position of the soil etc.
  • shift-up operation is carried out in spite of a small amount of accelerator pedal depression.
  • the work vehicle may be accelerated.
  • the operator must brake and stop the work vehicle in the loading position of the soil etc.
  • the work efficiency deteriorates.
  • the applicant of the present application has already proposed a transmission control device in which a loading position is set in a controller in advance, and shift-up operation by a transmission device is inhibited when the vehicle speed reaches a set speed or higher as long as a bucket is not lower than the set loading position (for example, see Patent Literature 2). In this manner, needless braking operation can be avoided so that the work efficiency of the work vehicle can be improved.
  • the closing/opening operation of the control valve is controlled in consideration of the height position of the work tool such as a bucket, so that the sense of discomfort or the sense of insecurity can be removed from the operator.
  • control to inhibit shift-up operation is carried out in consideration of the height position of the work tool such as a bucket, so that the work efficiency can be improved.
  • the height of the work tool during the excavation work, the height of the work tool during the hauling work and the height of the work tool during the loading work are required to be set properly as threshold values of control for the closing/opening operation of the control valve provided in the ride control device or for the automatic transmission control device.
  • the heights of the work tool depend on the preferences or habits of operators. Therefore, when the heights of the work tool are decided in one and the same way, it is difficult for all the operators to always obtain the aforementioned effects. For example, even when a certain value is set as the height of the work tool during the hauling work as to the control of the ride control device, the control valve cannot be changed over from the closed state to the open state during the hauling work for an operator who has a habit of travelling the work vehicle with the work tool kept at a height lower than the set height of the work tool. Thus, the effect of suppressing the vibration of the vehicle body by the ride control device cannot be obtained. Such a problem may occur in the same manner when the height of the work tool during the excavation work or the height of the work tool during the loading work does not match with the preference or habit of an operator.
  • An object of the invention is to provide a work vehicle which is capable of appropriately setting the height of a work tool as a control threshold value for a ride control device or an automatic transmission control device, and which is excellent in operability and work efficiency.
  • the invention provides a work vehicle including: a work tool which is moved vertically within a predetermined movable range by driving of a lift cylinder; a sensor which detects a height position of the work tool; and a controller which serves to control driving of a control target; wherein: the controller includes a signal import unit which imports a detection signal of the sensor as a signal of an excavation position by manual operation of an operator, a height position storage unit in which a specific height position of the work tool is stored as an offset value from the excavation position as to the control of driving of the control target, and a signal generating unit which generates a control signal for the control target in accordance with a height position of the work tool obtained from the detection signal of the sensor as soon as the obtained height position reaches the height position of the work tool stored in the height position storage unit.
  • the controller includes a signal import unit which imports a detection signal of the sensor as a signal of an excavation position by manual operation of an operator, a height position storage unit in which a specific height position of the work tool
  • the control target may include at least one of a ride control device by which circulation of hydraulic oil between the lift cylinder and a hydraulic pressure accumulator is changed over in accordance with a vehicle speed and the height position of the work tool, and a transmission control device by which a speed stage of a transmission is changed over in accordance with the vehicle speed, an engine speed and the height position of the work tool.
  • the sensor detects the height position of the work tool and outputs a detection signal in accordance with the detected height position of the work tool.
  • the signal import unit is of a manual operation type. In response to the operation by the operator, the detection signal of the sensor in accordance with the height position of the work tool at that time is imported as an excavation position signal.
  • the height of the work tool is desirably decided when the operator operates the signal import unit. Thus, the operator can reflect his/her own preference or habit on the setting of the excavation position.
  • a specific height position serving for controlling the driving of a control target such as the ride control device or the transmission control device for example, the height of the work tool during the hauling work, the height of the work tool during the loading work, or the like, is stored in the height position storage unit as an offset value from the excavation position set by the operation of the signal import unit.
  • the operator generally uses the amount of lifting-up of the work tool from the excavation position so as to adjust the height of the work tool during the hauling work, the height of the work tool during the loading work, etc. Therefore, when the specific height positions are stored in the height position storage unit as offset values from the excavation position, the preference or habit of the operator can be also reflected on these specific height positions.
  • a control signal for always appropriately controlling driving of the control target such as the ride control device or the transmission control device in accordance with the height position of the work tool can be generated in the signal generating unit, so that the operability and the work efficiency of the work vehicle can be improved.
  • a controller serving for controlling the driving of a control target is provided with a signal import unit by which a detection signal of a sensor for detecting the height position of a work tool is imported as a signal of an excavation position by manual operation of an operator, a height position storage unit in which a specific height position of the work tool is stored as an offset value from the excavation position imported by the signal import unit as to the control of the driving of the control target, and a signal generating unit which generates a control signal for the control target in accordance with a height position of the work tool obtained from the detection signal of the sensor as soon as the obtained height position reaches the height position of the work tool stored in the height position storage unit.
  • FIG. 1 An outline configuration view of a work vehicle according to Example 1.
  • FIG. 2 A configuration diagram of a travel vibration suppression device according to Example 1.
  • FIG. 3 A configuration diagram of a main controller according to Example 1.
  • FIG. 4 A table for explaining a height position and a flag stored in the main controller according to Example 1.
  • FIG. 5 A flow chart showing the operation of a work machine according to Example 1.
  • FIG. 6 A configuration diagram of a transmission control device provided in a work machine according to Example 2.
  • FIG. 7 A graph showing the relationship between a vehicle speed and a speed stage in the transmission control device according to Example 2.
  • FIG. 8 A graph showing the travel performance of the work machine according to Example 2.
  • FIG. 9 A view for explaining V-shape loading using the work machine according to Example 2.
  • FIG. 10 A view for explaining a change of a speed stage in a transmission during loading operation of soil etc. according to the background art.
  • FIG. 11 A view for explaining a change of a speed stage in a transmission during loading operation of soil etc. according to the present invention.
  • FIG. 12 A flow chart showing a transmission control process of a transmission according to Example 2.
  • a work vehicle according to Example 1 is characterized in that the invention is applied to a travel vibration suppression device called a ride control device.
  • a wheel loader 1 is mainly constituted by a rear vehicle body 3 provided with a cab 2 , a front vehicle body 5 connected to the front side (on the forward moving side of the wheel loader 1 ) of the rear vehicle body 3 through a connection pin 4 , rear wheels 6 and front wheels 7 provided in the rear vehicle body 3 and the front vehicle body 5 , a front work machine 8 attached to a front portion of the front vehicle body 5 , and a travel vibration suppression device 9 added to a hydraulic system of the front work machine 8 .
  • the rear wheels 6 and the front wheels 7 are connected to a transmission 37 (see FIG. 2 ) mounted on the rear vehicle body 3 , and driven by an engine 36 likewise mounted on the rear vehicle body 3 (see FIG. 2 ).
  • the front work machine 8 is driven by hydraulic oil ejected from a not-shown hydraulic pump which is driven by the engine 36 .
  • the not-shown hydraulic pump and the travel vibration suppression device 9 are mounted on the front vehicle body 5 .
  • the front vehicle body 5 is configured to be bent in the left/right direction with respect to the rear vehicle body 3 .
  • a not-shown steering device provided in the cab 2 is operated to bend the front vehicle body 5 in the left direction or the right direction with respect to the rear vehicle body 3 to thereby move the wheel loader 1 in that direction.
  • the front work machine 8 is constituted by an arm 11 , a bucket (work tool) 13 , a lift cylinder 16 , a bell crank 18 , a link member 19 and a bucket tilting cylinder 22 .
  • One end of the arm 11 is connected to the front vehicle body 5 through a connection pin 10 .
  • the bucket 13 is attached to a front end portion of the arm 11 through a connection pin 12 .
  • Opposite end portions of the lift cylinder 16 are connected to the front vehicle body 5 and the arm 11 through connection pins 14 and 15 .
  • the bell crank 18 is swingably connected to the arm 11 through a connection pin 17 .
  • the link member 19 has one end connected to the bell crank 18 and the other end connected to the bucket 13 .
  • Opposite end portions of the bucket tilting cylinder 22 are connected to the front vehicle body 5 and the bell crank 18 through connection pins 20 and 21 .
  • one arm 11 , one connection pin 12 , one connection pin 14 , one connection pin 15 and one lift cylinder 16 are provided in this Example, a pair of arms 11 , a pair of connection pins 12 , a pair of connection pins 14 , a pair of connection pins 15 and a pair of lift cylinders 16 are provided on the left and right sides of the bucket 13 in a real machine.
  • the lift cylinder 16 and the bucket tilting cylinder 22 are driven by hydraulic oil ejected from a not-shown hydraulic pump.
  • the lift cylinder 16 When the lift cylinder 16 is extended, the arm 11 and the bucket 13 move up.
  • the lift cylinder 16 is shrunk, the arm 11 and the bucket 13 move down.
  • the extension and shrinkage of the lift cylinder 16 that is, the upward and downward movement of the arm 11 and the bucket 13 can be carried out by operation on an operating instrument such as a control lever provided in the cab 2 .
  • the bucket tilting cylinder 22 is extended, the bucket 13 swings upward.
  • the bucket tilting cylinder 22 is shrunk, the bucket 13 swings downward.
  • the extension and shrinkage of the bucket tilting cylinder 22 that is, the upward and downward swing of the bucket 13 can be carried out by operation on an operating instrument such as a control lever provided in the cab 2 .
  • the travel vibration suppression device 9 is constituted by a hydraulic pressure accumulator 31 , a control valve 32 , a ride control portion 33 and a hydraulic circuit 34 .
  • Hydraulic oil circulates between the hydraulic pressure accumulator 31 and the lift cylinder 16 .
  • the flow of the hydraulic oil between the lift cylinder 16 and the hydraulic pressure accumulator 31 is changed over by the control valve 32 .
  • the open/close state of the control valve 32 is changed over by the ride control portion 33 .
  • the control valve 32 is operated to open and close by the hydraulic circuit 34 in accordance with an instruction from the ride control portion 33 .
  • a plurality of hydraulic pressure accumulators 31 may be provided in accordance with the size and volume of a hydraulic system in use.
  • the ride control portion 33 is constituted by a main controller 35 , an engine controller 38 , a ride control switch 39 , an angle sensor 40 , an indicator 42 and a manual operation type signal import switch (signal import unit) 46 .
  • the main controller 35 manages the entire control of the wheel loader 1 .
  • the engine controller 38 controls driving of the engine 36 and the transmission 37 .
  • the ride control switch 39 is operated by the operator.
  • the angle sensor 40 is attached coaxially with the connection pin 10 so as to detect the swing angle of the arm 11 with respect to the front vehicle body 5 .
  • the indicator 42 is connected to the main controller 35 through a monitor unit 41 .
  • the signal import switch 46 imports a detection signal of the angle sensor 40 into a storage portion in the main controller 35 .
  • the reference numeral 47 in FIG. 2 represents a torque converter which is a fluid joint provided between the engine 36 and the transmission 37 .
  • the aforementioned embodiment has a configuration in such a manner that driving of the engine 36 and driving of the transmission 37 are controlled by the engine controller 38
  • the configuration may be replaced by a configuration in which driving of the engine 36 and driving of the transmission 37 are controlled using controllers dedicated thereto respectively.
  • the aforementioned embodiment has a configuration in such a manner that the indicator 42 is connected to the main controller 35 through the monitor unit 41
  • the configuration may be replaced by a configuration in which the indicator 42 is displayed within the monitor unit 41 .
  • the aforementioned embodiment has a configuration in such a manner that the manual operation type signal import switch 46 is connected to the main controller 35
  • the configuration may be replaced by a configuration in which the signal import switch 46 is displayed within the monitor unit 41 .
  • the ride control switch 39 consists of an on/off switch, whose output signal is inputted to the main controller 35 .
  • the main controller 35 When the operator operates to turn on the ride control switch 39 , the main controller 35 outputs a changeover signal for the control valve 32 to change over the control valve 32 to the open state, so that the hydraulic oil can circulate between the lift cylinder 16 and the hydraulic pressure accumulator 31 .
  • the main controller 35 outputs a changeover signal for the control valve 32 to change over the control valve 32 to the closed state, so as to block the circulation of the hydraulic oil between the lift cylinder 16 and the hydraulic pressure accumulator 31 .
  • the operating state of the ride control switch 39 is displayed on the indicator 42 through the monitor unit 41 .
  • the main controller 35 controls driving of the engine 36 through the engine controller 38 , and at the same time, controls driving of the control valve 32 and the monitor unit 41 .
  • the control of the driving of the engine 36 and the control of the driving of the monitor unit 41 are well-known matters and not the scope and spirit of the invention. Therefore, their description will be omitted.
  • the main controller 35 includes an input portion 35 a , a height position storage portion 35 b , an arithmetic operation portion 35 c , a determination portion 35 d , a signal generating portion 35 e , an output portion 35 f and a CPU 35 g .
  • the input portion 35 a imports a detection signal of the angle sensor 39 and an output signal of the signal import switch 46 .
  • the height position storage portion 35 b stores a height position of the bucket 13 .
  • the arithmetic operation portion 35 c calculates the height position of the bucket 13 from the detection signal of the angle sensor 39 .
  • the determination portion 35 d determines whether the height position of the bucket 13 calculated by the arithmetic operation portion 35 c reaches the specific height position stored in the height position storage portion 35 b or not.
  • the signal generating portion 35 e generates an on/off signal for the control valve 32 in accordance with the height position of the bucket 13 calculated by the arithmetic operation portion 35 c when the determination portion 35 d concludes that the height position reaches the specific height position stored in the height position storage portion 35 b .
  • the output portion 35 f outputs the on/off signal generated by the signal generating portion 35 e to the control valve 32 .
  • the CPU 35 g drives these respective portions 35 a to 35 f along a predetermined program.
  • the arithmetic operation portion 35 c calculates the height position of the bucket 13 from the detection signal of the angle sensor 40 .
  • the height position of the bucket 13 corresponds to the height position of the connection pin 12 which connects the arm 11 with the bucket 13 .
  • the height position of the bucket 13 can be calculated from the swing radius of the connection pin 12 which is a known value, and the detection value of the angle sensor 39 .
  • a detection value of the angle sensor 39 obtained when the signal import switch 46 is operated by the operator is stored in the height position storage portion 35 b .
  • height position information as a reference for on/off control of the control valve 32 such as height position information of the bucket 13 during hauling work or height position information of the bucket 13 during loading work is stored in the height position storage portion 35 b in advance.
  • the height position information stored in the height position storage portion 35 b in response to the operation performed on the signal import switch 46 serves as height position information of the bucket 13 in the excavation position on which the preference or habit of the operator is reflected.
  • the height position information of the bucket 13 stored in the height position storage portion 35 b in advance is stored as an offset value from the height position stored in the height position storage portion 35 b in response to the operation performed on the signal import switch 46 .
  • the operator generally adjusts the bucket height during the hauling work, the bucket height during the loading work, etc. by means of the lifting-up amount of the bucket 13 from the excavation position. Accordingly, when the bucket height during the hauling work and the bucket height during the loading work are stored in the height position storage portion 35 b as offset values from the excavation position, the preference or habit of the operator can be reflected on those height positions.
  • FIG. 4 shows a storage format of the height position storage portion 35 b .
  • a lower limit position H0 and an upper limit position H4 of a movable range an excavation position H1 which is as high as or higher than the lower limit position H0 and which is set by the operator operating the signal import switch 46 , a hauling position H2 which is higher than the excavation position H1, and a loading position H3 which is lower than the upper limit position H4 and higher than the hauling position H2, are stored as to the vertical moving direction of the bucket 13 .
  • the lower limit position H0 of the bucket 13 is a position where the outer surface of the bucket 13 abuts against the ground, and the upper limit position H4 depends on the vehicle rank (size) of the wheel loader 1 .
  • the hauling position H2 corresponds to the height position of the bucket 13 during the hauling work
  • the loading position H3 corresponds to the height position of the bucket 13 during the loading work.
  • Each of the hauling position H2 and the loading position H3 is stored as an offset quantity from the excavation position H1.
  • a flag for selecting whether to permit to automatically change over the control valve 32 in accordance with the height position of the bucket 13 or not is stored in the height position storage portion 35 b as shown in FIG. 4 .
  • a check mark indicating permission to automatically change over the control valve 32 is stored for each of the case where the height position H of the bucket 13 is in a range of H0 ⁇ H ⁇ (H1+H2), the case where the height position H of the bucket 13 is in a range of (H1+H2) ⁇ H ⁇ (H1+H3) and the case where the height position H of the bucket 13 is in a range of (H1+H3) ⁇ H ⁇ H4.
  • the control valve 32 is automatically changed over in accordance with the height position H of the bucket 13 in the whole movable range of the bucket 13 . That is, in this example, the control valve 32 is changed over to the closed state when the height position H of the bucket 13 is in a range of H0 ⁇ H ⁇ (H1+H2) or when the height position H of the bucket 13 is in a range of (H1+H3) ⁇ H ⁇ H4, and the control valve 32 is changed over to the open state when the height position H of the bucket 13 is in a range of (H1+H2) ⁇ H ⁇ (H1+H3). In this manner, the bucket 13 can be prevented from oscillating during the excavation work and during the loading work.
  • the hydraulic circuit 34 is configured as follows. That is, as shown in FIG. 2 , a rod-side chamber 16 a of the lift cylinder 16 is connected to a hydraulic oil tank 43 through the control valve 32 , and a bottom-side chamber 16 b of the lift cylinder 16 is connected to the hydraulic pressure accumulator 31 through the control valve 32 .
  • the control valve 32 is a pilot operation valve, which is opened/closed in accordance with a hydraulic pilot signal from an electromagnetic pilot valve 44 for ride control.
  • the electromagnetic pilot valve 44 is operated to be changed over in accordance with a changeover signal outputted from the main controller 35 . That is, when a signal for changing over the control valve 32 to the open state is outputted from the main controller 35 , the electromagnetic pilot valve 44 opens an oil path to introduce the pilot pressure ejected from the pilot pump 45 to a pilot port of the control valve 32 so that the control valve 32 can be changed over to the open state. On the other hand, when a signal for changing over the control valve 32 to the closed state is outputted from the main controller 35 , the electromagnetic pilot valve 44 opens an oil path to drop the pilot pressure down to the hydraulic oil tank 43 so that the control valve 32 can be changed over to the closed state due to the elastic force of a built-in return spring.
  • Step S 1 the main controller 35 reads an output signal of the ride control switch 39 (Step S 1 ), and determines whether the output signal of the ride control switch 39 is an ON signal or not (Step S 2 ).
  • Step S 2 the routine of processing moves to Step S 7 , and the system is terminated (ended).
  • Step S 2 When it is concluded in Step S 2 that the output signal of the ride control switch 39 is an ON signal, the height position of the bucket 13 calculated by the main controller 35 is read (Step S 3 ), and the flag stored in the main controller 35 is read (Step S 4 ). After that, determination as to whether the read height position H of the bucket 13 is in a range of H0 ⁇ H ⁇ (H1+H2) or not (Step S 5 ) and determination as to whether permission to automatically change over the control valve 32 is given to the range of H0 ⁇ H ⁇ (H1+H2) by the operator or not (Step S 6 ) are carried out in this order.
  • Step S 5 When it is concluded in Step S 5 that the height position H of the bucket 13 is in the range of H0 ⁇ H ⁇ (H1+H2) and it is concluded in Step S 6 that permission to automatically change over the control valve 32 is given to the range of H0 ⁇ H ⁇ (H1+H2), the routine of processing moves to Step S 8 , in which a signal for changing over the control valve 32 to the closed state is outputted to the electromagnetic pilot valve 44 .
  • Step S 7 the routine of processing moves to Step S 7 , in which a signal for changing over the control valve 32 to the open state is outputted to the electromagnetic pilot valve 44 .
  • Step S 5 When it is concluded in Step S 5 that the height position H of the bucket 13 is not in the range of H0 ⁇ H ⁇ (H1+H2), the routine of processing moves to Step S 9 , in which it is determined whether the height position H of the bucket 13 is in a range of (H1+H2) ⁇ H ⁇ (H1+H3) or not.
  • Step S 9 When it is concluded in Step S 9 that the height position H of the bucket 13 is in the range of (H1+H2) ⁇ H ⁇ (H1+H3), the routine of processing moves to Step S 7 , in which a signal for changing over the control valve 32 to the open state is outputted to the electromagnetic pilot valve 44 .
  • Step S 9 it is concluded in Step S 9 that the height position H of the bucket 13 is not in the range of (H1+H2) ⁇ H ⁇ (H1+H3), determination as to whether the height position H of the bucket 13 is in a range of (H1+H3) ⁇ H ⁇ H4 or not (Step S 10 ) and determination as to whether permission to automatically change over the control valve 32 is given to the range of (H1+H3) ⁇ H ⁇ H4 by the operator or not (Step S 11 ) are carried out in this order.
  • Step S 10 When it is concluded in Step S 10 that the height position H of the bucket 13 is in the range of (H1+H3) ⁇ H ⁇ H4 and it is concluded in Step S 11 that permission to automatically change over the control valve 32 is given to the range of (H1+H3) ⁇ H ⁇ H4, the main controller 35 outputs, to the electromagnetic pilot valve 44 , a signal for changing over the control valve 32 to the closed state.
  • Step S 10 that permission to automatically change over the control valve 32 is not given to the range of (H1+H3) ⁇ H ⁇ H4, the routine of processing moves to Step S 7 , in which a signal for changing over the control valve 32 to the open state is outputted to the electromagnetic pilot valve 44 .
  • the work vehicle according to Example 1 can reflect the preference or habit of the operator on the height positions of the bucket 13 during the excavation work, during the hauling work and during the loading work, which height positions are involved in the control to open/close the control valve 32 provided in the travel vibration suppression device.
  • the control valve 32 can be prevented from being opened/closed in a state which is not intended by the operator, so that the travelling stability and the work efficiency of the wheel loader 1 can be improved.
  • Example 2 of the work vehicle according to the invention will be described.
  • the work vehicle according to Example 2 is characterized in that the invention is applied to a transmission control device mounted on a wheel loader.
  • the wheel loader has the same outline configuration as that of the wheel loader 1 according to Example 1 shown in FIG. 1 .
  • a not-shown input shaft of a torque converter 47 is linked with an output shaft of an engine 36 mounted on the wheel loader 1
  • a not-shown output shaft of the torque converter 47 is linked with a transmission 37 .
  • the torque converter 47 is a well-known fluid clutch which consists of an impeller, a turbine and a stator, so that the rotation of the engine 36 can be transmitted to the transmission 37 through the torque converter 47 .
  • the transmission 37 has a hydraulic pressure clutch for shifting its speed stage to any one of first to fourth gears, so that the rotation of the output shaft of the torque converter 47 can be shifted by the transmission 37 .
  • the shifted rotation is transmitted to the front wheels 7 and the rear wheels 6 through a propeller shaft 51 and an axle 52 so that the wheel loader 1 can travel.
  • the engine speed of the engine 36 is detected by an engine speed sensor 53 .
  • the engine 36 drives a hydraulic pump 57 for working. Hydraulic oil ejected from the hydraulic pump 57 for working is introduced into a lift cylinder 16 and a bucket tilting cylinder 22 through a directional control valve 54 .
  • the directional control valve 54 is driven by operation on a control lever 55 .
  • the lift cylinder 16 and the bucket tilting cylinder 22 are driven in accordance with the operating amount of the control lever 55 .
  • the torque converter 47 has a function of increasing output torque relatively to input torque, that is, a function of setting a torque ratio at 1 or higher.
  • e a torque converter speed ratio
  • the number of rotations of the output shaft of the torque converter 47 that is, the vehicle speed decreases
  • the torque converter speed ratio e decreases.
  • the vehicle can travel with a larger drive force (traction) due to the increase in torque ratio.
  • the transmission 37 is an automatic transmission with solenoid valves corresponding to respective speed stages. These solenoid valves are driven in accordance with a control signal outputted from a main controller 35 to a transmission control device 56 , so that the speed stage can be automatically shifted to anyone of the first to fourth gears.
  • the stage of the first gear to the stage of the fourth gear are provided as the speed stages for the transmission 37 .
  • FIG. 7 is a graph showing the relationship between a vehicle speed v and a speed stage.
  • the main controller 35 outputs a control signal to the transmission control device 56 in accordance with the vehicle speed v so as to shift a gear in the transmission 37 in accordance with the vehicle speed v as shown in FIG. 7 . That is, when the vehicle speed v increases to a gear shift permission vehicle speed v12, the gear is shifted up from the first gear to the second gear. When the vehicle speed v increases from the gear shift permission vehicle speed v12 to a gear shift permission vehicle speed v23, the gear is shifted up from the second gear to the third gear.
  • the gear shift permission vehicle speeds v12, v23 and v34 are set to be higher than the gear shift permission vehicle speeds v21, v32 and v43 respectively so that the gear can be shifted stably.
  • Each of the gear shift permission vehicle speeds is a threshold value for permission to shift up or down the gear.
  • the gear shift permission vehicle speeds are set in the main controller 35 in advance.
  • the transmission control device 56 consists of solenoid valves corresponding to the respective speed stages. The solenoid valves are driven in accordance with a control signal from the main controller 35 .
  • the main controller 35 decreases the gear shift permission vehicle speeds when the engine speed of the engine 36 is low, and increases the gear shift permission vehicle speeds when the engine speed of the engine 36 is high. In this manner, the main controller 35 changes the gear shift permission vehicle speeds in accordance with the engine speed of the engine 36 so as to obtain an effect in reducing the fuel consumption.
  • FIG. 8 is a graph showing the travel performance of the wheel loader 1 according to the Example.
  • gear shift permission speeds for shifting up the gear are depicted in FIG. 8 .
  • gear shift permission speeds for shifting down the gear are depicted in FIG. 8 .
  • Intersection points x1, x2 and x3 of curves indicating travel performance in the respective speed stages move as shown by arrows a1, a2 and a3 respectively when the engine speed of the engine 36 decreases.
  • the gear shift permission speeds are generally set at the intersection points x1, x2 and x3.
  • vehicle speed ranges referenced by A, B and C designate the ranges where the gear shift permission speeds v12, v23 and v34 vary in accordance with the engine speed of the engine 36 .
  • a first set height and a second set height are defined for the height of the bucket 13 in advance.
  • the main controller 35 increases (raises) the gear shift permission speeds v23 and v34 to gear shift permission vehicle speeds v23a and v34a as shown in FIG. 8 regardless of the engine speed of the engine 36 , so that the gear is hardly shifted up from the second gear to the third gear or from the third gear to the fourth gear.
  • the main controller 35 forbids shifting up from the second gear to the third gear and from the third gear to the fourth gear.
  • the gear shift permission speeds v23a and v34a are set at values which are, for example, about 10% higher than the maximum values of the gear shift permission speeds v23 and v34 varying in accordance with the engine speed of the engine 36 respectively. Incidentally, even when the height of the bucket 13 exceeds the second set height, shifting down is not forbidden.
  • the first set height and the second set height are stored in the height position storage portion 35 b as offset values from the excavation position which is imported into the height position storage portion 35 b by the operator operating the signal import switch 46 , in the same manner as in the work vehicle according to Example 1.
  • the height position of the bucket 13 during the hauling work (a hauling position H2) and the height position of the bucket 13 during the loading work (a loading position H3) may be set as the first set height and the second set height, in the same manner as in the work vehicle according to Example 1.
  • a pedal operation amount detector 62 detects the amount of operation on an accelerator pedal 61 .
  • the rotation number detector 63 detects the number Ni of rotations in the input shaft of the torque converter 47 .
  • the rotation number detector 64 detects the number Nt of rotations in the output shaft of the torque converter 47 .
  • the vehicle speed detector 65 detects the rotation speed of the output shaft of the transmission 37 , that is, the vehicle speed v.
  • a forward/backward movement changeover switch 67 issues an instruction to move the vehicle forward/backward.
  • the shift switch 68 issues an instruction of a maximum speed stage among the first to fourth gears.
  • the manual/automatic transmission changeover unit 70 changes over the transmission 37 between automatic transmission and manual transmission.
  • the main controller 35 controls the engine speed (the number of rotations) of the engine 36 in accordance with the amount of operation on the accelerator pedal 61 .
  • the main controller 35 changes each gear shift permission vehicle speed in accordance with the height of the bucket 13 calculated based on the engine speed of the engine 36 detected by the engine speed sensor 53 and the height of the bucket 13 calculated based on the detection value of the angle sensor 40 .
  • the main controller 35 does not permit output of a shift-up signal to the transmission control device 56 , so as to forbid shifting up in the transmission 37 .
  • FIG. 9 is a view for explaining V-shape loading which is one of methods for loading soil etc. on a dump truck.
  • V-shape loading the wheel loader 1 is first moved forward to scoop up soil etc. as shown by the arrow a, and then the wheel loader 1 is once moved backward as shown by the arrow b. Then, the wheel loader 1 is moved forward toward the dump truck to load the scooped soil etc. on the dump truck as shown by the arrow c, and the wheel loader 1 is moved backward to its original position as shown by the arrow d.
  • the speed stage of the transmission 37 changes in the background-art wheel loader 1 during the work of loading soil etc. on the dump truck.
  • the wheel loader 1 is moved forward toward the dump truck while lifting up the bucket 13 .
  • the speed stage is in the first gear or the second gear at the beginning (start time) of the forward movement toward the dump truck.
  • the gear shift permission vehicle speed v23 decreases as described above.
  • the vehicle speed reaches the gear shift permission vehicle speed v23 to shift up the speed stage from the second gear to the third gear before the bucket 13 moves up to the height required for loading on the dump truck.
  • the speed stage of the transmission 37 changes at the time of loading soil etc. on the dump truck as shown in FIG. 11 .
  • the gear shift permission speeds v23 and v34 are increased to the gear shift permission speeds v23a and v34a as shown in FIG. 8 when the height of the bucket 13 exceeds the first set height.
  • shift-up from the second gear to the third gear and from the third gear to the fourth gear is forbidden when the height of the bucket 13 exceeds the second set height.
  • the first set height that is, the height position of the bucket 13 during the hauling work is generally set in a position which is slightly higher than the height position of the bucket 13 during the excavation work, as described above. Therefore, when the wheel loader 1 begins to lift up the bucket 13 while moving forward toward the dump truck, the bucket 13 reaches the first set height quickly. When the height of the bucket 13 exceeds the first set height, the gear shift permission speed v23 is increased to v23a. Thus, the timing of shifting up from the second gear to the third gear is delayed in comparison with that in the background-art wheel loader 1 . It is therefore possible to suppress the rising of the vehicle speed caused by the shift-up.
  • the timing of shifting up from the second gear to the third gear can be delayed in comparison with that in the background-art wheel loader 1 .
  • shifting up from the second gear to the third gear is forbidden when the height of the bucket 13 exceeds the second set height. Accordingly, it is possible to prevent the problem that the wheel loader 1 may arrive at the dump truck due to acceleration caused by shift-up before the bucket 13 moves up to the height required for loading on the dump truck.
  • FIG. 12 is a flow chart showing the operation of a transmission control process of the transmission 37 in the wheel loader 1 according to the embodiment.
  • a program for carrying out the process shown in FIG. 12 is started up and executed repeatedly in the main controller 35 .
  • Step S 1 the engine speed of the engine 36 detected by the engine speed sensor 53 is read, and the routine of processing advances to Step S 3 .
  • Step S 3 each gear shift permission speed is changed and set as shown in FIG. 8 in accordance with the engine speed of the engine 36 read in Step S 1 , and the routine of processing advances to Step S 5 .
  • Step S 5 the height of the bucket 13 is calculated based on the detection value of the angle sensor 40 , and the routine of processing advances to Step S 7 .
  • Step S 7 it is determined whether the height of the bucket 13 calculated in Step S 5 exceeds the first set height (more strictly, the excavation position H1+the hauling position H2) or not.
  • the routine of processing advances to Step S 9 , in which the gear shift permission speeds v23 and v34 are changed to and set at the aforementioned gear shift permission speeds v23a and v34a, and the routine of processing advances to Step S 11 .
  • Step S 11 it is determined whether the height of the bucket 13 calculated in Step S 5 exceeds the second set height (more strictly, the excavation position H1+the loading position H3) or not.
  • the routine of processing advances to Step S 13 , in which it is determined whether the current speed stage selected in the transmission 37 is in the second or third gear or not, based on information about the selected state of the speed stage outputted from the transmission control device 56 .
  • Step S 17 a well-known transmission control operation is carried out based on each gear shift permission speed set in Step S 3 , and a control signal indicating shift-up or shift-down is outputted to the transmission control device 56 in accordance with the necessity of gear shift. Then, the routine of processing returns.
  • Step S 17 when Step S 9 has been executed, a transmission control operation on which a result of the execution of Step S 9 is reflected is carried out.
  • Step S 17 when Step S 15 has been executed, a transmission control operation on which a result of the execution of Step S 15 is reflected is carried out. As a result, shifting up from the second gear to the third gear and from the third gear to the fourth gear is forbidden.
  • Step S 17 When the conclusion in any one of Steps S 7 , S 11 and S 13 is No, the routine of processing advances to Step S 17 .
  • the preference or habit of the operator can be reflected on the height position of the bucket 13 during the hauling work involved in the delay of shift-up by the transmission control device 56 and the height position of the bucket 13 during the loading work involved in the forbiddance of shift-up by the transmission control device 56 . Accordingly, the delay of shift-up or the forbiddance of shift-up can be prevented from being cancelled in a state which is not intended by the operator. It is therefore possible to improve the operability, the travel stability and the work efficiency of the wheel loader 1 .
  • the present invention can be used for improvement in operability and travel stability in work vehicles such as a wheel loader and a fork lift.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Operation Control Of Excavators (AREA)
US14/360,963 2011-12-19 2012-10-05 Work Vehicle Abandoned US20140330490A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2011277310A JP5707313B2 (ja) 2011-12-19 2011-12-19 作業車両
JP2011-277310 2011-12-19
PCT/JP2012/075986 WO2013094283A1 (fr) 2011-12-19 2012-10-05 Véhicule de travail

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/075986 A-371-Of-International WO2013094283A1 (fr) 2011-12-19 2012-10-05 Véhicule de travail

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US15/361,267 Continuation US10704223B2 (en) 2011-12-19 2016-11-25 Work vehicle

Publications (1)

Publication Number Publication Date
US20140330490A1 true US20140330490A1 (en) 2014-11-06

Family

ID=48668188

Family Applications (2)

Application Number Title Priority Date Filing Date
US14/360,963 Abandoned US20140330490A1 (en) 2011-12-19 2012-10-05 Work Vehicle
US15/361,267 Active 2033-03-11 US10704223B2 (en) 2011-12-19 2016-11-25 Work vehicle

Family Applications After (1)

Application Number Title Priority Date Filing Date
US15/361,267 Active 2033-03-11 US10704223B2 (en) 2011-12-19 2016-11-25 Work vehicle

Country Status (7)

Country Link
US (2) US20140330490A1 (fr)
EP (1) EP2796625B1 (fr)
JP (1) JP5707313B2 (fr)
KR (1) KR101971646B1 (fr)
CN (1) CN104011302B (fr)
IN (1) IN2014KN01152A (fr)
WO (1) WO2013094283A1 (fr)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180016768A1 (en) * 2015-03-27 2018-01-18 Sumitomo(S.H.I.) Construction Machinery Co., Ltd. Shovel
US9943023B2 (en) 2014-08-01 2018-04-17 Kubota Corporation Lift control apparatus for ground work apparatus
CN108097746A (zh) * 2018-02-16 2018-06-01 广西建工集团智慧制造有限公司 一种工业用可翻转式手自一体化钢筋线材放料架
US10030364B2 (en) 2015-10-26 2018-07-24 Caterpillar Inc. Hydraulic system having automatic ride control
US10323389B2 (en) * 2016-04-08 2019-06-18 Caterpillar Inc. Control system and method for a machine
CN110651087A (zh) * 2017-10-04 2020-01-03 株式会社小松制作所 控制装置及控制方法
US10866579B2 (en) * 2019-03-01 2020-12-15 Toyota Motor Engineering & Manufacturing North America, Inc. Automated manufacturing process tooling setup assist system
US20200407951A1 (en) * 2018-06-29 2020-12-31 Komatsu Ltd. Work machine and system including work machine
US20210002852A1 (en) * 2018-03-26 2021-01-07 Sumitomo Construction Machinery Co., Ltd. Shovel
US11015706B2 (en) * 2019-05-09 2021-05-25 Zf Friedrichshafen Ag Method and device for controlling a transmission of a working machine
US20220127816A1 (en) * 2020-10-28 2022-04-28 Deere & Company Container load assist system and method for a work vehicle
US11408146B2 (en) 2017-04-28 2022-08-09 Komatsu Ltd. Work machine and method for controlling the same
US20220389684A1 (en) * 2019-09-30 2022-12-08 Komatsu Ltd. Work machine and method for controlling work machine
US11608614B2 (en) 2020-12-23 2023-03-21 Caterpillar Inc. Loading machine with selectable performance modes
US11708682B2 (en) 2017-09-21 2023-07-25 Hitachi Construction Machinery Co., Ltd. Construction machine
US20230279642A1 (en) * 2020-09-29 2023-09-07 Komatsu Ltd. Work machine
US11881061B2 (en) 2018-06-29 2024-01-23 Komatsu Ltd. Work machine and system including work machine
US11946230B2 (en) 2020-10-28 2024-04-02 Deere & Company Container load assist system and method for a work vehicle
US12024851B2 (en) 2018-09-12 2024-07-02 Komatsu Ltd. Loading machine control device and control method

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5707313B2 (ja) * 2011-12-19 2015-04-30 日立建機株式会社 作業車両
US10563376B2 (en) * 2014-10-13 2020-02-18 Sandvik Mining And Construction Oy Arrangement for controlling a work machine
JP6883813B2 (ja) * 2014-10-27 2021-06-09 ヤンマーパワーテクノロジー株式会社 トラクタ
JP6735249B2 (ja) * 2017-03-30 2020-08-05 日立建機株式会社 作業機械の走行振動抑制装置
US10480155B2 (en) 2017-12-19 2019-11-19 Caterpillar Trimble Control Technologies Llc Excavator implement teeth grading offset determination
WO2019180843A1 (fr) * 2018-03-20 2019-09-26 日立建機株式会社 Véhicule de travail
JP7034010B2 (ja) * 2018-06-04 2022-03-11 日立建機株式会社 ホイール式作業機械
US11898331B2 (en) 2020-12-02 2024-02-13 Caterpillar Sarl System and method for detecting objects within a working area
JP7523394B2 (ja) 2021-03-24 2024-07-26 日立建機株式会社 ホイールローダ

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010044685A1 (en) * 1999-07-15 2001-11-22 William L. Schubert Apparatus and method for facilitating reduction of vibration in a work vehicle having an active cab suspension system
US7344351B2 (en) * 2003-09-12 2008-03-18 Deere & Company Electronic boom height sensor
US20120010790A1 (en) * 2009-03-27 2012-01-12 Komatsu Ltd. Fuel consumption saving control device for work vehicle and fuel consumption saving method for work vehicle
US20120155999A1 (en) * 2009-10-05 2012-06-21 Komatsu Ltd. Travel vibration suppressing device of work vehicle
US20130103247A1 (en) * 2010-06-23 2013-04-25 Doosan Infracore Co., Ltd. Apparatus and Method for Controlling Work Trajectory of Construction Equipment

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5147172A (en) 1991-09-03 1992-09-15 Caterpillar Inc. Automatic ride control
US20050002742A1 (en) * 2002-12-11 2005-01-06 Martin Bachmann Method and device for transporting powdery substances
SE526989C2 (sv) * 2004-04-19 2005-11-29 Volvo Constr Equip Holding Se Metod för skakning av arbetsredskap
KR100997310B1 (ko) * 2006-02-01 2010-11-29 닛본 덴끼 가부시끼가이샤 등화 장치 및 등화 방법
US20080047170A1 (en) * 2006-08-24 2008-02-28 Trimble Navigation Ltd. Excavator 3D integrated laser and radio positioning guidance system
JP4559493B2 (ja) * 2008-01-24 2010-10-06 住友建機株式会社 2段折れ式高所解体機の作業範囲規制装置
US8428832B2 (en) * 2008-12-23 2013-04-23 Caterpillar Inc. Method and apparatus for calculating payload weight
JP5270464B2 (ja) * 2009-06-17 2013-08-21 日立建機株式会社 産業車両の変速制御装置
JP2011056644A (ja) 2009-09-14 2011-03-24 Sumitomo Forestry Co Ltd 釘打機又はねじ打機用ガイド
JP5503955B2 (ja) 2009-12-14 2014-05-28 日立建機株式会社 作業車両の変速制御装置
JP5690620B2 (ja) * 2011-03-15 2015-03-25 日立建機株式会社 走行振動抑制装置を備えた作業車両
JP5707313B2 (ja) * 2011-12-19 2015-04-30 日立建機株式会社 作業車両

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010044685A1 (en) * 1999-07-15 2001-11-22 William L. Schubert Apparatus and method for facilitating reduction of vibration in a work vehicle having an active cab suspension system
US7344351B2 (en) * 2003-09-12 2008-03-18 Deere & Company Electronic boom height sensor
US20120010790A1 (en) * 2009-03-27 2012-01-12 Komatsu Ltd. Fuel consumption saving control device for work vehicle and fuel consumption saving method for work vehicle
US20120155999A1 (en) * 2009-10-05 2012-06-21 Komatsu Ltd. Travel vibration suppressing device of work vehicle
US20130103247A1 (en) * 2010-06-23 2013-04-25 Doosan Infracore Co., Ltd. Apparatus and Method for Controlling Work Trajectory of Construction Equipment

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9943023B2 (en) 2014-08-01 2018-04-17 Kubota Corporation Lift control apparatus for ground work apparatus
US11015319B2 (en) * 2015-03-27 2021-05-25 Sumitomo(S.H.I.) Construction Machinery Co., Ltd. Vehicle shovel
US12110652B2 (en) 2015-03-27 2024-10-08 Sumitomo(S.H.I.) Construction Machinery Co., Ltd. Vehicle shovel
US20180016768A1 (en) * 2015-03-27 2018-01-18 Sumitomo(S.H.I.) Construction Machinery Co., Ltd. Shovel
US10030364B2 (en) 2015-10-26 2018-07-24 Caterpillar Inc. Hydraulic system having automatic ride control
US10323389B2 (en) * 2016-04-08 2019-06-18 Caterpillar Inc. Control system and method for a machine
US11408146B2 (en) 2017-04-28 2022-08-09 Komatsu Ltd. Work machine and method for controlling the same
US11708682B2 (en) 2017-09-21 2023-07-25 Hitachi Construction Machinery Co., Ltd. Construction machine
CN110651087A (zh) * 2017-10-04 2020-01-03 株式会社小松制作所 控制装置及控制方法
CN108097746A (zh) * 2018-02-16 2018-06-01 广西建工集团智慧制造有限公司 一种工业用可翻转式手自一体化钢筋线材放料架
US20210002852A1 (en) * 2018-03-26 2021-01-07 Sumitomo Construction Machinery Co., Ltd. Shovel
US20200407951A1 (en) * 2018-06-29 2020-12-31 Komatsu Ltd. Work machine and system including work machine
US11881061B2 (en) 2018-06-29 2024-01-23 Komatsu Ltd. Work machine and system including work machine
US12098527B2 (en) * 2018-06-29 2024-09-24 Komatsu Ltd. Work machine and system including work machine
US12024851B2 (en) 2018-09-12 2024-07-02 Komatsu Ltd. Loading machine control device and control method
US10866579B2 (en) * 2019-03-01 2020-12-15 Toyota Motor Engineering & Manufacturing North America, Inc. Automated manufacturing process tooling setup assist system
US11015706B2 (en) * 2019-05-09 2021-05-25 Zf Friedrichshafen Ag Method and device for controlling a transmission of a working machine
US20220389684A1 (en) * 2019-09-30 2022-12-08 Komatsu Ltd. Work machine and method for controlling work machine
US20230279642A1 (en) * 2020-09-29 2023-09-07 Komatsu Ltd. Work machine
US20220127816A1 (en) * 2020-10-28 2022-04-28 Deere & Company Container load assist system and method for a work vehicle
US11946230B2 (en) 2020-10-28 2024-04-02 Deere & Company Container load assist system and method for a work vehicle
US11608614B2 (en) 2020-12-23 2023-03-21 Caterpillar Inc. Loading machine with selectable performance modes

Also Published As

Publication number Publication date
US10704223B2 (en) 2020-07-07
CN104011302B (zh) 2016-12-14
JP2013127187A (ja) 2013-06-27
JP5707313B2 (ja) 2015-04-30
EP2796625A1 (fr) 2014-10-29
US20170073923A1 (en) 2017-03-16
IN2014KN01152A (fr) 2015-10-16
EP2796625B1 (fr) 2017-07-19
CN104011302A (zh) 2014-08-27
KR101971646B1 (ko) 2019-04-23
WO2013094283A1 (fr) 2013-06-27
EP2796625A4 (fr) 2016-05-04
KR20140112513A (ko) 2014-09-23

Similar Documents

Publication Publication Date Title
US10704223B2 (en) Work vehicle
JP5161380B1 (ja) 作業車両及び作業車両の制御方法
CN102656390B (zh) 作业车辆的变速控制装置及轮式装载机
JP5192605B1 (ja) ホイールローダ
JP5092070B1 (ja) ホイールローダ及びホイールローダの制御方法
EP2538121B1 (fr) Véhicule de travail et procédé de commande d'un véhicule de travail
US8504257B2 (en) Work vehicle and method of controlling the same
CN102803686B (zh) 工作车辆和工作车辆的控制方法
JP5192601B1 (ja) 作業車両及び作業車両の制御方法
JP5113946B1 (ja) 作業車両及び作業車両の制御方法
JP2009103258A (ja) 作業車両および作業車両の制御方法
KR20090083425A (ko) 산업 차량의 변속 제어 장치
JP5270464B2 (ja) 産業車両の変速制御装置
WO2020194953A1 (fr) Chargeuse sur roues
KR102452805B1 (ko) 휠 로더의 제어 방법 및 시스템

Legal Events

Date Code Title Description
AS Assignment

Owner name: HITACHI CONSTRUCTION MACHINERY CO., LTD., JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:AOKI, ISAMU;HYODO, KOJI;TANAKA, TETSUJI;AND OTHERS;SIGNING DATES FROM 20140424 TO 20140425;REEL/FRAME:032978/0404

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION