CN112012972B - Pilot control oil way and control method for super-tonnage excavator - Google Patents
Pilot control oil way and control method for super-tonnage excavator Download PDFInfo
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- CN112012972B CN112012972B CN202010870359.XA CN202010870359A CN112012972B CN 112012972 B CN112012972 B CN 112012972B CN 202010870359 A CN202010870359 A CN 202010870359A CN 112012972 B CN112012972 B CN 112012972B
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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
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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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- 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
- F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
- F15B1/02—Installations or systems with accumulators
- F15B1/021—Installations or systems with accumulators used for damping
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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
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
-
- 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
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/025—Pressure reducing 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
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
- F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
- F15B13/043—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with electrically-controlled pilot valves
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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
- F16N—LUBRICATING
- F16N7/00—Arrangements for supplying oil or unspecified lubricant from a stationary reservoir or the equivalent in or on the machine or member to be lubricated
- F16N7/38—Arrangements for supplying oil or unspecified lubricant from a stationary reservoir or the equivalent in or on the machine or member to be lubricated with a separate pump; Central lubrication systems
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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
- F15B2211/635—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements
- F15B2211/6355—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements having valve means
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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)
Abstract
The invention discloses a pilot control oil way of a super-tonnage excavator and a control method, and belongs to the field of engineering machinery. The pressure oil of the pilot pump is respectively connected with a Psv port of the variable displacement pump, an electromagnetic valve A2 and an electromagnetic valve A1; a first oil outlet of the electromagnetic valve A2 is connected to an oil tank through a throttle valve, and a second oil outlet of the electromagnetic valve A2 is respectively connected with an electromagnetic valve group and an overflow valve; an oil outlet of the electromagnetic valve A1 is connected to a motor in the butter filling system; the electromagnetic valve group is connected with the Pi port and the Pp port of the variable displacement pump and the pilot valve group of the main valve. After the excavator is started, the pilot oil way provides proper pressure for different mechanisms according to actual working conditions, so that long-term high-pressure overflow of a pilot system is avoided, and energy consumption is reduced; the vehicle-mounted controller periodically controls an electromagnetic valve for driving the grease filling system to efficiently lubricate each mechanism of the excavator, and a pressure reducing valve is arranged on a driving oil path of the grease filling system, so that the pressure of a driving motor is not influenced by pressure switching.
Description
Technical Field
The invention relates to the field of engineering machinery, in particular to a pilot control oil way of a super-tonnage excavator and a control method.
Technical Field
The pilot system of the super-tonnage excavator is different from that of a small and medium-sized excavator, and the pilot system not only provides pilot pressure for the control of a main pump, but also provides pressure for an enabling control port, a power and discharge control port and a grease system of the main pump. Different functions require different pressures, the pilot control port of the main valve requires a pressure of about 50bar, and the enabling control port of the main pump and the driving pressure of the centralized lubrication only require 20 bar. Therefore, the existing pilot system is often in a high-pressure overflow state according to different working conditions, and consumes hydraulic energy.
Disclosure of Invention
In order to solve the technical problem, the invention provides a pilot control oil way of an ultra-large tonnage excavator.
The invention is realized by the following technical scheme: a pilot control oil way of a super-tonnage excavator is characterized in that the pressure oil of a pilot pump is respectively connected with a variable pump Psv port, an electromagnetic valve A2 and an electromagnetic valve A1; a first oil outlet of the electromagnetic valve A2 is connected to an oil tank through a throttle valve, and a second oil outlet of the electromagnetic valve A2 is respectively connected with an electromagnetic valve group and an overflow valve; the oil outlet of the electromagnetic valve A1 is connected to a motor in a butter filling system; the electromagnetic valve group is connected with a Pi port and a Pp port of the variable displacement pump and a pilot valve group of a main valve.
It further comprises the following steps: a check valve S1 is installed in an oil passage between the pilot pump pressure oil and the solenoid valve a 1.
And a pressure reducing valve is arranged in an oil path from the electromagnetic valve A1 to a motor in the butter filling system.
The electromagnetic valve group comprises a discharge valve K1, a power valve K2 and a safety valve K3; the discharge valve K1 is respectively connected with the Pi port of the variable pump and a second oil outlet of an electromagnetic valve A2; the power valve K2 is respectively connected with the Pp port of the variable pump and a second oil outlet of the electromagnetic valve A2; and the safety valve K3 is respectively connected with the main valve pilot valve group and the second oil outlet of the electromagnetic valve A2.
And a check valve S2 is installed in an oil path between the safety valve K3 and the second oil outlet of the electromagnetic valve A2, and an accumulator is connected in an oil path between the safety valve K3 and the check valve S2.
A pilot control oil way control method of a super-tonnage excavator,
after the excavator is started up,
when the safety handle is not opened, the electromagnetic valve A1 is electrified; the first path of the pressure oil of the pilot pump passes through an electromagnetic valve A2 and a throttle valve oil return tank, and the generated pressure is 20 bar; the second path of the pilot pump pressure oil controls an enabling control port Psv of the variable pump to enable the variable pump to start working; the third way of the pilot pump pressure oil passes through a one-way valve S1, an electromagnetic valve A1 and a pressure reducing valve, and drives a motor of a butter filling system;
when the safety handle is opened, a safety valve K3 of the electromagnetic valve group is electrified with an electromagnetic valve A2, the pressure oil of the pilot pump is connected to the overflow valve 6, and the system pressure is 50bar at the moment; after the safety valve K3 is electrified, the electromagnetic valve group is communicated with the main valve pilot valve group, the electric pilot handle is controlled, and the excavator starts to work;
when the electric pilot handle returns to the middle position for 6s, the electromagnetic valve A2 loses electricity, the electromagnetic valve A2 is switched to the left position, and the pressure of the pilot system returns to 20 bar;
by operating any electrical pilot handle, solenoid valve a2 is energized, solenoid valve a2 switches to the right position, and the pilot system pressure switches to 50 bar.
It further comprises the following steps: the electric pilot handle is connected with the vehicle-mounted controller; when the electric pilot handle is controlled, the controller outputs electric signals to control the displacement valve K1 and the power valve K2 in the main valve pilot valve group and the electromagnetic valve group, and further control the displacement and the power of the variable pump.
The electromagnetic valve A1 is connected with a vehicle-mounted controller; the vehicle-mounted controller controls the electromagnetic valve A1 to be electrified, after the electromagnetic valve A1 is electrified, the pilot pump pressure oil is communicated with a motor of the grease filling system, and the grease filling system starts to work; after one working cycle of the butter filling system is finished, the electromagnetic valve A1 is powered off, and after 8 minutes, the vehicle-mounted controller controls the electromagnetic valve A1 to be powered on again.
Compared with the prior art, the invention has the beneficial effects that:
1. after the excavator is started, the pilot oil way provides proper pressure for different mechanisms according to actual working conditions, so that long-term high-pressure overflow of a pilot system is avoided, and energy consumption is reduced;
2. the vehicle-mounted controller periodically controls an electromagnetic valve for driving the grease filling system to efficiently lubricate each mechanism of the excavator, and a pressure reducing valve is arranged on a driving oil path of the grease filling system, so that the pressure of a driving motor is not influenced by pressure switching.
Drawings
FIG. 1 is a hydraulic schematic of the present invention;
FIG. 2 is a control schematic of the present invention;
in the figure: 1. the system comprises an electromagnetic valve bank, 2 an energy accumulator, 3 a butter filling system, 4 a pressure reducing valve, 6 an overflow valve, 9 a throttle valve, 10 a variable displacement pump and 11 a main valve pilot valve bank.
Detailed Description
The following is a specific embodiment of the present invention, which will be further described with reference to the accompanying drawings.
Example one
A pilot control oil way of a super-tonnage excavator,
the pressure oil of the pilot pump is respectively connected with a variable pump 10Psv port, an electromagnetic valve A2 and an electromagnetic valve A1;
a first oil outlet of the electromagnetic valve A2 is connected to an oil tank through a throttle valve 9, and a second oil outlet of the electromagnetic valve A2 is respectively connected with the electromagnetic valve group 1 and the overflow valve 6;
an oil outlet of the electromagnetic valve A1 is connected to a motor in the butter filling system; a check valve S1 is arranged in an oil path between the pressure oil of the pilot pump and the electromagnetic valve A1; a pressure reducing valve 4 is arranged in an oil path between the electromagnetic valve A1 and a motor in the butter filling system, and the pressure reducing valve is an adjustable pressure reducing valve, so that the motor is prevented from being influenced by the pressure high-pressure and low-pressure switching of a pilot system;
the solenoid valve group 1 comprises a discharge valve K1, a power valve K2 and a safety valve K3; the discharge valve K1 is respectively connected with a Pi port of the variable pump 10 and a second oil outlet of the electromagnetic valve A2; the power valve K2 is respectively connected with a port Pp of the variable pump 10 and a second oil outlet of the electromagnetic valve A2; and the safety valve K3 is respectively connected with the main valve pilot valve group 11 and the second oil outlet of the electromagnetic valve A2. A check valve S2 is installed in an oil path between the safety valve K3 and the second oil outlet of the electromagnetic valve A2, an energy accumulator 2 is connected in the oil path between the safety valve K3 and the check valve S2, and the energy accumulator 2 can reduce hydraulic impact and play a good buffering role.
Example two
A pilot control oil way control method for a super-tonnage excavator comprises the following steps on the basis of the first embodiment:
the present embodiment uses the solenoid valve a2 to realize switching of high and low pressures;
after the excavator is started up,
when the safety handle is not opened, the electromagnetic valve A1 is electrified; the first path of the pressure oil of the pilot pump returns to the oil tank through the electromagnetic valve A2 and the throttle valve 9, back pressure is generated through the throttle valve, the pressure is 20bar, and the pressure is used for supplying oil to an enabling control port Psv of the variable pump 10 and a butter filling system; specifically, the method comprises the following steps: the second path of the pilot pump pressure oil controls an enabling control port Psv of the variable pump 10 to enable the variable pump 10 to start working; the third way of the pilot pump pressure oil passes through a one-way valve S1, an electromagnetic valve A1 and a pressure reducing valve 7, a motor of a butter filling system is driven, and the excavator starts to pump butter;
when the safety handle is opened, a safety valve K3 of the electromagnetic valve group 1 is electrified with an electromagnetic valve A2, the pressure oil of the pilot pump is connected to the overflow valve 6, and the system pressure is 50bar at the moment; after the safety valve K3 is electrified, the electromagnetic valve group 1 is communicated with the main valve pilot valve group 11, the electric pilot handle is controlled, and the excavator starts to work;
when the electric pilot handle returns to the middle position for 6s, the electromagnetic valve A2 loses electricity, the electromagnetic valve A2 is switched to the left position, and the pressure of the pilot system returns to 20 bar;
when any electric pilot handle is operated, the electromagnetic valve A2 is electrified, the electromagnetic valve A2 is switched to the right position, and the pressure of a pilot system is switched to 50 bar;
the pilot system of the excavator obtains proper pressure in different working states, and the purpose of energy conservation is achieved.
Preferably: the electric pilot handle is connected with the vehicle-mounted controller; when the electric pilot handle is controlled, the controller outputs an electric signal to control the displacement valve K1 and the power valve K2 in the main valve pilot valve group 11 and the electromagnetic valve group 1, so as to control the displacement and the power of the variable displacement pump 10.
Preferably: the electromagnetic valve A1 is connected with a vehicle-mounted controller; the vehicle-mounted controller clock controls the electromagnetic valve A1 to be electrified, after the electromagnetic valve A1 is electrified, the pilot pump pressure oil is communicated with a motor of the grease filling system, and the grease filling system starts to work; after one working cycle of the butter filling system is finished, the electromagnetic valve A1 is powered off; after 8 minutes the onboard controller again controls solenoid a1 to be energized again.
After the excavator is started, the pilot oil way of the embodiment provides proper pressure for different mechanisms according to actual working conditions, and avoids long-term high-pressure overflow of a pilot system. The vehicle-mounted controller periodically controls an electromagnetic valve for driving the grease filling system, so that each mechanism of the excavator can be efficiently lubricated.
Claims (5)
1. A pilot control oil way of a super-tonnage excavator,
the method is characterized in that:
the pilot pump pressure oil is respectively connected with a Psv port of the variable displacement pump (10), an electromagnetic valve A2 and an electromagnetic valve A1;
a first oil outlet of the electromagnetic valve A2 is connected to an oil tank through a throttle valve (9), and a second oil outlet of the electromagnetic valve A2 is respectively connected with the electromagnetic valve group (1) and the overflow valve (6);
the oil outlet of the electromagnetic valve A1 is connected to a motor in a butter filling system;
the electromagnetic valve group (1) is connected with a Pi port and a Pp port of the variable pump (10) and a main valve pilot valve group (11);
a check valve S1 is installed in an oil path between the pilot pump pressure oil and the electromagnetic valve A1;
a pressure reducing valve (4) is installed in an oil path between the electromagnetic valve A1 and a motor in the butter filling system;
the electromagnetic valve group (1) comprises a discharge valve K1, a power valve K2 and a safety valve K3; the discharge valve K1 is respectively connected with a Pi port of the variable pump (10) and a second oil outlet of an electromagnetic valve A2; the power valve K2 is respectively connected with the Pp port of the variable pump (10) and a second oil outlet of the electromagnetic valve A2; and the safety valve K3 is respectively connected with the main valve pilot valve group (11) and the second oil outlet of the electromagnetic valve A2.
2. The pilot control oil way of the ultra-large tonnage excavator according to claim 1, characterized in that: and a check valve S2 is installed in an oil path between the safety valve K3 and the second oil outlet of the electromagnetic valve A2, and an accumulator (2) is connected in an oil path between the safety valve K3 and the check valve S2.
3. A pilot control oil way control method of a super-tonnage excavator adopts the pilot control oil way of the super-tonnage excavator, which is characterized in that:
after the excavator is started up,
when the safety handle is not opened, the electromagnetic valve A1 is electrified; the first path of the pressure oil of the pilot pump returns to the oil tank through an electromagnetic valve A2 and a throttle valve (9), and the generated pressure is 20 bar; the second path of the pilot pump pressure oil controls an enabling control port Psv of the variable pump (10) to enable the variable pump (10) to start working; the third way of the pilot pump pressure oil passes through a one-way valve S1, an electromagnetic valve A1 and a pressure reducing valve (4) to drive a motor of the butter filling system;
when the safety handle is opened, a safety valve K3 of the electromagnetic valve group (1) is electrified with an electromagnetic valve A2, the pilot pump pressure oil is connected to the overflow valve 6, and the system pressure is 50bar at the moment; after the safety valve K3 is electrified, the electromagnetic valve group (1) is communicated with the main valve pilot valve group (11), the electric pilot handle is controlled, and the excavator starts to work;
when the electric pilot handle returns to the middle position for 6s, the electromagnetic valve A2 loses electricity, the electromagnetic valve A2 is switched to the left position, and the pressure of the pilot system returns to 20 bar;
by operating the electric pilot handle, the solenoid valve A2 is energized, the solenoid valve A2 is switched to the right position, and the pilot system pressure is switched to 50 bar.
4. The pilot control oil way control method of the ultra-large tonnage excavator according to claim 3, characterized in that: the electric pilot handle is connected with the vehicle-mounted controller; when the electric pilot handle is controlled, the controller outputs an electric signal to control the discharge valve K1 and the power valve K2 in the main valve pilot valve group (11) and the electromagnetic valve group (1), and further control the discharge capacity and the power of the variable displacement pump (10).
5. The pilot control oil way control method for the ultra-large tonnage excavator according to claim 3, characterized in that: the electromagnetic valve A1 is connected with a vehicle-mounted controller; the vehicle-mounted controller controls the electromagnetic valve A1 to be electrified, after the electromagnetic valve A1 is electrified, the pilot pump pressure oil is communicated with a motor of the grease filling system, and the grease filling system starts to work; after one working cycle of the butter filling system is finished, the electromagnetic valve A1 is powered off; after 8 minutes the onboard controller again controls solenoid a1 to be energized again.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010870359.XA CN112012972B (en) | 2020-08-26 | 2020-08-26 | Pilot control oil way and control method for super-tonnage excavator |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010870359.XA CN112012972B (en) | 2020-08-26 | 2020-08-26 | Pilot control oil way and control method for super-tonnage excavator |
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| CN112012972A CN112012972A (en) | 2020-12-01 |
| CN112012972B true CN112012972B (en) | 2022-05-10 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115059863A (en) * | 2022-06-28 | 2022-09-16 | 徐州徐工矿业机械有限公司 | Automatic lubricating system and method for excavator |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000144813A (en) * | 1998-11-13 | 2000-05-26 | Hitachi Constr Mach Co Ltd | Hydraulic circuit for hydraulic shovel |
| CN102828942A (en) * | 2011-06-16 | 2012-12-19 | 中联重科股份有限公司 | Constant power control device and method of variable pump and concrete pumping device |
| CN107725505A (en) * | 2017-09-25 | 2018-02-23 | 柳工常州机械有限公司 | Hydraulic system with different accessory flow regulating functions |
| CN108910788A (en) * | 2018-06-28 | 2018-11-30 | 江苏理工学院 | Telescopic arm forklift truck and the hydraulic system impacted for improving its starting |
| CN110307143A (en) * | 2019-06-21 | 2019-10-08 | 江苏恒立液压科技有限公司 | A kind of variable servo valve, power servo valve and variable pump |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180319634A1 (en) * | 2014-10-30 | 2018-11-08 | Xuzhou Heavy Machinery Co., Ltd. | Crane hydraulic system and controlling method of the system |
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2020
- 2020-08-26 CN CN202010870359.XA patent/CN112012972B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000144813A (en) * | 1998-11-13 | 2000-05-26 | Hitachi Constr Mach Co Ltd | Hydraulic circuit for hydraulic shovel |
| CN102828942A (en) * | 2011-06-16 | 2012-12-19 | 中联重科股份有限公司 | Constant power control device and method of variable pump and concrete pumping device |
| CN107725505A (en) * | 2017-09-25 | 2018-02-23 | 柳工常州机械有限公司 | Hydraulic system with different accessory flow regulating functions |
| CN108910788A (en) * | 2018-06-28 | 2018-11-30 | 江苏理工学院 | Telescopic arm forklift truck and the hydraulic system impacted for improving its starting |
| CN110307143A (en) * | 2019-06-21 | 2019-10-08 | 江苏恒立液压科技有限公司 | A kind of variable servo valve, power servo valve and variable pump |
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