WO1991010784A1 - System for changing over running speed of hydraulic excavator - Google Patents
System for changing over running speed of hydraulic excavator Download PDFInfo
- Publication number
- WO1991010784A1 WO1991010784A1 PCT/JP1991/000043 JP9100043W WO9110784A1 WO 1991010784 A1 WO1991010784 A1 WO 1991010784A1 JP 9100043 W JP9100043 W JP 9100043W WO 9110784 A1 WO9110784 A1 WO 9110784A1
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- WO
- WIPO (PCT)
- Prior art keywords
- traveling
- spring
- valve
- pressure
- switching
- Prior art date
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/4148—Open loop circuits
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
- E02F9/2253—Controlling the travelling speed of vehicles, e.g. adjusting travelling speed according to implement loads, control of hydrostatic transmission
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
- F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
- F15B11/044—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed by means in the return line, i.e. "meter out"
- F15B11/0445—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed by means in the return line, i.e. "meter out" with counterbalance valves, e.g. to prevent overrunning or for braking
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/42—Control of exclusively fluid gearing hydrostatic involving adjustment of a pump or motor with adjustable output or capacity
- F16H61/423—Motor capacity control by fluid pressure control means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/42—Control of exclusively fluid gearing hydrostatic involving adjustment of a pump or motor with adjustable output or capacity
- F16H61/433—Pump capacity control by fluid pressure control means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/46—Automatic regulation in accordance with output requirements
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/46—Automatic regulation in accordance with output requirements
- F16H61/47—Automatic regulation in accordance with output requirements for achieving a target output speed
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20546—Type of pump variable capacity
- F15B2211/20553—Type of pump variable capacity with pilot circuit, e.g. for controlling a swash plate
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/305—Directional control characterised by the type of valves
- F15B2211/30505—Non-return valves, i.e. check valves
- F15B2211/30515—Load holding valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/31—Directional control characterised by the positions of the valve element
- F15B2211/3122—Special positions other than the pump port being connected to working ports or the working ports being connected to the return line
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/505—Pressure control characterised by the type of pressure control means
- F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
- F15B2211/50545—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using braking valves to maintain a back pressure
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
- F15B2211/5153—Pressure control characterised by the connections of the pressure control means in the circuit being connected to an output member and a directional control valve
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/605—Load sensing circuits
- F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/605—Load sensing circuits
- F15B2211/6058—Load sensing circuits with isolator valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/67—Methods for controlling pilot pressure
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
- F15B2211/7058—Rotary output members
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/75—Control of speed of the output member
Definitions
- the present invention relates to a traveling speed switching device for a hydraulic excavator, and in particular, by switching the traveling speed to three or more stages, to select an optimal traveling speed according to road surface conditions and work conditions,
- the present invention relates to a traveling speed switching device for a hydraulic excavator that improves simultaneous operability during fine operation of a work machine. Background
- the traveling speed of a hydraulic excavator is controlled by controlling the discharge pressure of a hydraulic pump 51 with left and right traveling control valves 52a and 52b / siberge. It is controlled by supplying to left and right traveling motors 54a and 54b via point 53.
- the travel speed switching switch 55 is set to the first speed, the solenoid 56 a of the control pressure switching valve 56 is demagnetized, so that the control pressure switching valve 56 is in the a position. It becomes.
- the traveling speed switching valves 58a and 58b of the left and right traveling motors 54a and 54b and the output cylinders 59a and 59b Since the control pressure switching valve 56 is connected to the tank 66 via the joint 53, the traveling speed switching valves 58a and 58b are also at the a position. As a result, the driving motor capacity control cylinder Since the dams 60a and 60b are connected to the tank 66, the capacities of the left and right traveling motors 54a and 54b are increased, and the first traveling speed stage is established.
- the traveling operation valves 52a and 52b are respectively operated to positions a by a traveling operation lever (not shown)
- the oil discharged from the hydraulic pump 51 is supplied to the left and right traveling motors 54a.
- 54b are supplied to the left and right traveling motors 54a, 54b via the driving lines 61a, 61b, and the traveling motors 54a, 54b force, and the discharge line 62a , 62b, but the counter-noise valves 63a, 63b are set to the a position respectively by the working oil pressure of the drive pipelines 61a, 61b.
- the hydraulic oil discharged to the discharge pipes 6 2a and 6 2b passes through the counter valve and the lance valves 63 a and 63 b, so that the hydraulic oil is swiveled.
- the return pipe (not shown) returns to the tank &'6 via the return pipe (not shown) via the port 53 and the travel operation valves 52a and 52b. Accordingly, since the left and right traveling motors 54a and 54b are image-produced by the first traveling speed stage at an image number corresponding to the operation amount of the traveling operation lever, the surface rotation is performed.
- the vehicle can move forward or backward at a speed that depends on the number.
- Reference numeral 64 denotes a load sensing valve, which is the first of the load sensing valve 64, and the hydraulic chamber 51 is connected to the load chamber 64.
- the discharge oil is led to the second pilot chamber
- the traveling operation valves 52a, 52b and the check valves 65a, 65b provide a driving line 6 la for the traveling motors 54a, 54b at 64c.
- the solenoid 56a of the control pressure switching valve 56 is not energized.
- the pressure switching valve 56 is in the b position.
- the traveling speed switching valves 58a, 58b of the left and right traveling motors 54a, 54b are at the b position.
- the drive hydraulic pressures of the left and right travel motors 54a, 54b are supplied to the travel motor displacement control cylinders 60a, 60b, so that the left and right travel motors 54a, The capacity of 54b is reduced, and the second speed stage is established.
- the operation of the travel control valves 52a and 52b is the same as that in the case of the first-speed travel speed stage, and will not be described.
- the traveling speed of the traveling motors 54a, 54b Since the gears are two-stage switching, if the high gear and the low gear are set to the optimal gears for the work conditions and road surface conditions, the speed difference becomes too large, and either the high gear or the low gear is changed. If the optimal speed was set, the other speed would be too fast or too slow, and the operator had a disadvantage that it was difficult for the operator to select the optimal speed stage according to work conditions and road surface conditions. . Also, since the discharge oil amount of the hydraulic pump 51 is generally set to be maximum while the vehicle is running, operating the work implement while the vehicle is running is, for example, a small operation.
- the present invention has a drawback that the traveling speed of the vehicle is reduced and the simultaneous operability is reduced due to the occurrence of load sway and the like.
- a spring adjuster is provided to adjust the traveling speed of the traveling motor to multiple speeds to optimize speed for road conditions, and to reduce the simultaneous operability even when operating the work equipment while the vehicle is traveling. It is an object to provide a traveling speed switching device for a hydraulic excavator without any. Disclosure of the invention
- the present invention provides a load sensing device that supplies oil discharged from a hydraulic pump to left and right traveling motors via left and right traveling operation valves to control a capacity control cylinder of the hydraulic pump.
- the hydraulic pressure of the hydraulic pump is guided to the first pipe port chamber of the valve, and the driving pressure of the traveling motor is supplied to the second and third chambers of the valve. Guiding, the first, the capacity control of the hydraulic pump by the balance between the thrust of the pilot chamber, the thrust of the second pilot chamber and the force of the differential pressure setting spring.
- a travel control device for a hydraulic excavator for controlling a cylinder a spring set-ca adjusting device for switching a set-ca of the differential pressure setting spring to a plurality of stages is provided.
- This device includes a traveling speed switching switch, a controller that processes the setting signal, an electromagnetic control pressure switching valve that is activated by the controller's command, and an electromagnetic control pressure switch.
- a spring force adjusting cylinder for adjusting the set pressure of the differential pressure setting spring of the load sensing valve by operating the switching valve.
- a traveling speed switching switch a controller for processing the set signal, an electromagnetic control pressure switching valve operated by a controller command, and an electromagnetic control pressure
- a traveling motor displacement switching device comprising a traveling motor displacement switching valve for switching the displacement of the traveling motor in two stages by operating a switching valve and a traveling motor displacement control cylinder.
- the amount of oil Q passing through the control valve is determined by the upstream pressure P of the control valve.
- the upstream pressure PP of the travel operation valves Ri discharge pressure der hydraulic port down-flop
- the downstream pressure P _ is Ri driving ⁇ Dea traveling motors
- the pressure difference P P -! PL is loaded Since it is determined by the spring force F of the differential pressure setting spring of the sensing valve
- the spring force F is switched to a plurality of stages, the hydraulic pump discharge amount Q of the plurality of stages with respect to the operation amount (opening) A of the same traveling control valve, in other words, the plurality of stages. Running and speed are obtained. Further, if a traveling motor capacity switching device for switching the capacity of the traveling motor to two stages is provided, the traveling speed stages of the plurality of stages are doubled. The traveling speed is switched to multiple stages by selectively connecting the spring set force adjusting device or the traveling motor displacement switching device to the control pressure source or the tank by an electromagnetic control pressure switching valve. Can be replaced. BRIEF DESCRIPTION OF THE DRAWINGS FIG.
- FIG. 1 is a hydraulic circuit diagram of a traveling speed control device of a hydraulic excavator according to an embodiment of the present invention
- FIG. 2 is a hydraulic pump discharge amount and a comparison between the embodiment of the present invention and the prior art
- FIG. 3 is a diagram showing the relationship of the discharge hydraulic pressure
- FIG. 3 is a hydraulic circuit diagram of a conventional traveling speed control device.
- the traveling speed of the hydraulic excavator is controlled by controlling the discharge oil of the hydraulic pump 1 by the left and right traveling control valves 2a and 2b.
- the control is performed by supplying to left and right traveling motors 4a and 4b via 3.
- the traveling speed control of the hydraulic excavator is specifically controlled as follows. First, when the traveling speed switching switch 5 is set to the first speed stage, the setting signal of the traveling speed switching switch 5 is transmitted via the controller 7 to the solenoid of the control pressure switching valve 6. In order to demagnetize the node 6a, the control pressure switching valve 6 is set to the a position, and the spring force adjusting cylinder 9 is connected to the tank 10.
- the spring rod 9b in the spring force adjusting cylinder 9 causes the screw rod 9b to move to the left, and the differential pressure setting spring 1 1 of the load sensing valve 1 1 1 a), the discharge oil amount Q of the hydraulic pump 1 can be reduced even if the operation amounts (openings) A of the travel operation valves 2a and 2b are the same in the above equation (2).
- the set pressure F of the differential pressure setting spring 11a is reduced by the amount corresponding to the decrease, and the traveling speed is also reduced by that amount.
- the setting signal of the traveling speed switching switch 5 passes through the controller 7 to demagnetize the solenoid 12a of the control pressure switching valve 12 so that the control signal is deactivated.
- the pressure switching valve 12 is set to the a position, and the pilot cylinders 14 a and 14 b of the traveling motor capacity switching valves 13 a and 13 b communicate with the tank 10. To Therefore, the traveling motor capacity The quantity changeover valves 13a and 13b are in the a position, and the traveling motor capacity control cylinders 15a and 15b communicate with the tank. b is set to a large capacity and travels at one speed.
- the setting signal of the traveling speed switching switch 5 is transmitted via the controller 7 to the solenoid of the control pressure switching valve 6.
- the control pressure switching valve 6 is set to the a position, and the spring force adjusting cylinder 9. is connected to the tank 10. Therefore, the piston rod 9b in the spring force adjusting cylinder 9 moves leftward by the spring 9a, and the differential pressure setting spring 11a of the load sensing valve 11 is moved.
- the set oil F of the hydraulic pump 1 decreases in the above equation (2) even if the operation amounts (openings) A of the travel operation valves 2a and 2b are the same in the above equation (2).
- the differential pressure setting spring 11 decreases by the amount of the setka F of the 1a, and the traveling speed also decreases by that amount.
- the setting signal of the traveling speed switching switch 5 is passed through the controller 7 to excite the solenoid 12a of the control pressure switching valve 12 so that the control pressure switching is performed.
- the valve 12 is in the b position, and the pilot cylinders 14 a and 14 b of the traveling motor displacement switching valves 13 a and 13 b are connected to the control pump 8. Therefore, the traveling motor displacement valves 13a and 13b are in the position b, and the traveling motor driving pressure is supplied to the traveling motor displacement control cylinders 15a and 15b.
- Running motors 4a and 4b are set to small capacity and run at two speeds. Run.
- the traveling speed switching switch 5 when the traveling speed switching switch 5 is set to the third speed stage, the setting signal of the traveling speed switching switch 5 is transmitted to the controller 7 via the controller 7 to control the control pressure switching valve 6.
- the control pressure switching valve 6 is set to the position “b”, and the spring force adjusting cylinder 9 is connected to the control pump 8. Accordingly, the piston rod 9b in the spring force adjusting cylinder 9 overcomes the spring force of the spring 9a and moves rightward to set the differential pressure setting spring of the load sensing valve 11.
- the discharge oil amount Q of the hydraulic pump 1 Increases by the increase of the setka F of the differential pressure setting spring 11a, and the traveling speed also increases by that amount.
- the setting signal of the traveling speed switching switch 5 is supplied to the solenoid valve 2a of the control pressure switching valve 12 via the control port 7 so that the control pressure switching valve 12 is activated.
- the position b is set, and the drive cylinder displacement switching valves 13a 'and 13b are connected to the control pump 8 by the eject cylinders 14a and 14b.
- the traveling motor displacement switching valves 13a and 13b are at the position b, and the traveling motor drive pressure is supplied to the traveling motor displacement control cylinders 15a and 15b.
- the left and right traveling motors 4a and 4b are set to small capacity and travel at three speeds.
- the left and right traction motors 4a and 4b force are discharged to the discharge lines 18a and 18b, but the counter-norance valves 20a and 2b 0b is at the position a by the drive hydraulic pressure of the drive pipelines 16a and 16b, respectively, so the operation discharged to the discharge pipelines 18a and 18b
- the oil passes through counter balance valves 20a and 20b, passes through divergence point 3, travel speed switching valves 2a and 2b, returns from a return line (not shown), It is returned to link 10.
- the vehicle can be moved forward or backward at a speed corresponding to the rotation speed. Wear . If the position a of the cruise control valves 2a and 2b is the forward direction of the vehicle, the position b is the backward direction of the vehicle.However, the operation in this case is the same as that of the forward direction of the vehicle. Therefore, the description is omitted.
- the discharge oil of the hydraulic pump 1 is led to the first chamber of the load sensing valve 11, i.e., the outlet chamber 11 b, and the second pilot chamber 11 c
- the traveling operation valves 2a and 2b and the check valves 21a and 21b are used to select one of the driving pipelines 16a and 16b of the traveling motors 4a and 4b.
- a higher driving pressure is introduced, and the differential pressure between the first pilot chamber 11b and the second pilot chamber 11c (the differential pressure setting spring 1 In response to the seta F) of 1a, the discharge hydraulic pressure of the hydraulic pump 1 is reduced to actuate the displacement control cylinder '1a of the hydraulic pump 1 to be controlled.
- a differential pressure corresponding to the spring force of the spring 11a of the load sensing valve 11 is always generated upstream and downstream of the traveling operation valves 2a and 2b, and the hydraulic pressure is adjusted.
- the discharge oil amount of the pump 1 is always controlled according to the operation amount of the travel operation valves 2a and 2b.
- FIG. 2 shows the relationship between the discharge amount Q of the hydraulic pump and the load pressure P in the present invention.
- Table 1 the relationship between the first speed stage and the second speed stage is shown in Table 1.
- the simultaneous operability is improved without lowering the traveling speed. can do.
- FIGS. 2 (b) and 2 (c) show the conventional technology for comparison.
- (B) is a running state in which 100% of the discharge amount of the hydraulic pump 1 is supplied to the left and right traveling motors 4a and 4b (the operation amount of the traveling operation valves 2a and 2b is full).
- (c) if the work machine is further operated to supply 20% of the discharge amount of the hydraulic pump 1, the remaining 80% is supplied to the left and right traveling motors.
- Driving speed 2 Decrease to reduce simultaneous operability Table 1
- the present invention relates to a traveling speed switching device for a hydraulic excavator, which facilitates selection of an optimal traveling speed according to road surface conditions and work conditions by switching the traveling speed to three or more stages. It is useful as a traveling speed switching device that improves the simultaneous operability during fine operation of the vehicle.
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Operation Control Of Excavators (AREA)
- Fluid-Pressure Circuits (AREA)
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1019920701621A KR0141976B1 (ko) | 1990-01-18 | 1991-01-17 | 유압굴삭기의 주행속도 변환장치 |
EP91902759A EP0511387B1 (en) | 1990-01-18 | 1991-01-17 | System for changing over running speed of hydraulic excavator |
DE69120254T DE69120254T2 (de) | 1990-01-18 | 1991-01-17 | System für das wechseln der fahrgeschwindigkeit eines hydraulikbaggers |
US07/910,261 US5331812A (en) | 1990-01-18 | 1991-01-17 | Traveling speed changeover device for hydraulic excavator |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2009762A JP2520314B2 (ja) | 1990-01-18 | 1990-01-18 | 油圧掘削機の走行速度切換装置 |
JP2/9762 | 1990-01-18 |
Publications (1)
Publication Number | Publication Date |
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WO1991010784A1 true WO1991010784A1 (en) | 1991-07-25 |
Family
ID=11729288
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP1991/000043 WO1991010784A1 (en) | 1990-01-18 | 1991-01-17 | System for changing over running speed of hydraulic excavator |
Country Status (6)
Country | Link |
---|---|
US (1) | US5331812A (ja) |
EP (1) | EP0511387B1 (ja) |
JP (1) | JP2520314B2 (ja) |
KR (1) | KR0141976B1 (ja) |
DE (1) | DE69120254T2 (ja) |
WO (1) | WO1991010784A1 (ja) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2668516A1 (fr) * | 1990-10-31 | 1992-04-30 | Samsung Heavy Ind | Systeme de commande pour commander automatiquement des moyens d'actionnement d'une excavatrice. |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4307872C2 (de) * | 1993-03-12 | 2001-05-17 | Orenstein & Koppel Ag | Lastdruckunabhängige Steuerung der Geschwindigkeit von hydraulischen Stellelementen |
US5553453A (en) * | 1995-05-18 | 1996-09-10 | Caterpillar, Inc. | Method for providing different speed ranges for a speed pedal |
WO1997010457A1 (de) * | 1995-09-11 | 1997-03-20 | O & K Mining Gmbh | Verfahren und einrichtung zur lastabhängigen automatischen umschaltung von fahrmotoren |
JP2002087336A (ja) * | 2000-09-21 | 2002-03-27 | Kobelco Contstruction Machinery Ltd | 速度切換機能付き建設機械 |
US20030230083A1 (en) * | 2002-06-14 | 2003-12-18 | John Dorscht | Continuously variable torque shredder drive |
KR101155718B1 (ko) * | 2004-12-31 | 2012-06-12 | 두산인프라코어 주식회사 | 굴삭기의 주행제어장치 |
US7571605B2 (en) * | 2007-01-03 | 2009-08-11 | Clark Equipment Company | Synchronized speed shifting of multiple motors |
DE102010009704A1 (de) * | 2010-03-01 | 2011-09-01 | Robert Bosch Gmbh | Hydraulischer Fahrantrieb und Verfahren zum Steuern eines derartigen Fahrantriebs |
CN103782069B (zh) * | 2011-08-26 | 2016-05-18 | 沃尔沃建筑设备公司 | 用于操作液压驱动式工程机械的驱动控制方法和系统 |
CN102359587B (zh) * | 2011-08-31 | 2014-03-05 | 贵州詹阳动力重工有限公司 | 轮式液压挖掘机手自一体变速系统 |
KR102597793B1 (ko) * | 2016-11-02 | 2023-11-03 | 에이치디현대인프라코어 주식회사 | 굴삭기 |
CN106763743B (zh) * | 2016-12-26 | 2019-02-12 | 潍柴动力股份有限公司 | 一种静液压传动移动换档控制方法及系统 |
JP6959905B2 (ja) * | 2018-11-29 | 2021-11-05 | 日立建機株式会社 | 油圧駆動装置 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS49100090U (ja) * | 1972-12-21 | 1974-08-28 | ||
JPS59106333A (ja) * | 1982-12-09 | 1984-06-20 | Daikin Ind Ltd | 回転体駆動液圧回路 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3203165A (en) * | 1962-08-10 | 1965-08-31 | New York Air Brake Co | Hydraulic device |
JPS49100090A (ja) * | 1973-01-30 | 1974-09-20 | ||
DE3340332C2 (de) * | 1983-11-08 | 1988-11-10 | Hydromatik GmbH, 7915 Elchingen | Leistungs-Regelvorrichtung für einen hydrostatischen Antrieb mit Fördermengeneinstellung |
KR920010875B1 (ko) * | 1988-06-29 | 1992-12-19 | 히다찌 겐끼 가부시기가이샤 | 유압구동장치 |
US5177964A (en) * | 1989-01-27 | 1993-01-12 | Hitachi Construction Machinery Co., Ltd. | Hydraulic drive traveling system |
KR940009219B1 (ko) * | 1989-03-30 | 1994-10-01 | 히다찌 겐끼 가부시기가이샤 | 장궤식차량의 유압구동장치 |
-
1990
- 1990-01-18 JP JP2009762A patent/JP2520314B2/ja not_active Expired - Lifetime
-
1991
- 1991-01-17 WO PCT/JP1991/000043 patent/WO1991010784A1/ja active IP Right Grant
- 1991-01-17 KR KR1019920701621A patent/KR0141976B1/ko not_active IP Right Cessation
- 1991-01-17 DE DE69120254T patent/DE69120254T2/de not_active Expired - Fee Related
- 1991-01-17 EP EP91902759A patent/EP0511387B1/en not_active Expired - Lifetime
- 1991-01-17 US US07/910,261 patent/US5331812A/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS49100090U (ja) * | 1972-12-21 | 1974-08-28 | ||
JPS59106333A (ja) * | 1982-12-09 | 1984-06-20 | Daikin Ind Ltd | 回転体駆動液圧回路 |
Non-Patent Citations (1)
Title |
---|
See also references of EP0511387A4 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2668516A1 (fr) * | 1990-10-31 | 1992-04-30 | Samsung Heavy Ind | Systeme de commande pour commander automatiquement des moyens d'actionnement d'une excavatrice. |
Also Published As
Publication number | Publication date |
---|---|
DE69120254D1 (de) | 1996-07-18 |
EP0511387B1 (en) | 1996-06-12 |
US5331812A (en) | 1994-07-26 |
EP0511387A1 (en) | 1992-11-04 |
DE69120254T2 (de) | 1996-10-10 |
KR920703939A (ko) | 1992-12-18 |
JPH03212523A (ja) | 1991-09-18 |
EP0511387A4 (en) | 1993-04-07 |
JP2520314B2 (ja) | 1996-07-31 |
KR0141976B1 (ko) | 1999-02-18 |
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