CN109281874B - Pilot hydraulic control main loop unloading system and pile press - Google Patents

Pilot hydraulic control main loop unloading system and pile press Download PDF

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Publication number
CN109281874B
CN109281874B CN201811483152.6A CN201811483152A CN109281874B CN 109281874 B CN109281874 B CN 109281874B CN 201811483152 A CN201811483152 A CN 201811483152A CN 109281874 B CN109281874 B CN 109281874B
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oil
valve
pilot
control
port
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CN109281874A (en
Inventor
傅祖范
赵黎明
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CHTC Jove Heavy Industry Co Ltd
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CHTC Jove Heavy Industry Co Ltd
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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
    • F15B1/022—Installations or systems with accumulators used as an emergency power source, e.g. in case of pump failure
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
    • E02D7/20—Placing by pressure or pulling power
    • 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
    • F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
    • 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
    • F15B13/024—Pressure relief valves
    • 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
    • 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
    • F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/212—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

The invention provides a pilot hydraulic control main loop unloading system and a pile pressing machine, which comprise an oil cylinder (3), a main valve (1), a pilot valve (2), an oil pump (5) and an energy accumulator (6), wherein the outlet of the oil pump is connected with a driving oil path (8) and a control oil path (9), the driving oil path is connected with the oil inlet of the main valve, the control oil path is connected with the oil inlet of the pilot valve, and a charging and discharging energy port of the energy accumulator is connected to the control oil path. The energy accumulator is arranged on the hydraulic main loop of the engineering machinery, when the oil pump stops, the energy accumulator releases energy to drive the main valve, so that oil pressure remained in a system pipeline can be discharged in time when the oil pump stops working, the safety performance of the pipeline during disassembly is effectively ensured, and the energy accumulator is very suitable for the engineering machinery which needs to be disassembled and transferred to a site, and is particularly suitable for a pile pressing machine.

Description

Pilot hydraulic control main loop unloading system and pile press
Technical Field
The invention relates to the field of large-scale engineering machinery, in particular to a pilot hydraulic control main loop unloading system and a pile press.
Background
At present, large-scale engineering machinery such as a hydrostatic pile press is widely applied to the fields of urban bridges, buildings, road traffic construction and the like, the flow of a hydraulic system of the large-tonnage hydrostatic pile press (which is referred to as a pile press in the application for short) in the working process is large and generally reaches more than 400L/min, and the main valve needs great strength by adopting a common manual operation reversing valve, so a manual pilot valve is generally adopted to control the main valve, a relatively common hydraulic system such as a hydraulic system shown in fig. 1 is adopted as the main valve 1, a hydraulic control reversing valve is adopted as the main valve 1, a hydraulic control signal of the main valve is controlled by a pilot valve 2, and the main valve has a middle-position O-shaped function due to the requirement of working conditions, so that all oil paths are kept in a non-communicated closed.
The weight of a large-tonnage pile press can reach more than 200 tons, the size of the large-tonnage pile press is large, the width of the large-tonnage pile press after general expansion is more than 10 meters, the pile press needs to be disassembled and packaged for transportation in the process of converting a construction site, an oil cylinder 3 of the pile press needs to be disassembled for independent transportation because the height of the oil cylinder exceeds the transportation height, except that a structural part needs to be disassembled after shutdown, a hydraulic pipeline needs to be disassembled together, a joint 4 (see figure 1) is arranged at an oil inlet and an oil outlet of a rod cavity and a rodless cavity in a general disassembling position, and because a main valve is positioned at a middle position after shutdown, high-pressure oil exists in an oil pipe, no method is provided for pressure relief, the high-pressure oil can be sprayed in the process of disassembling the joint, and great. Therefore, there is a need in the art for a solution to this problem.
Disclosure of Invention
The invention aims to provide a pilot hydraulic control main loop unloading system and a pile press, which aim to solve the problems in the background technology.
A pilot-operated hydraulic control main loop unloading system comprises an oil cylinder 3, a main valve 1, a pilot valve 2, an oil pump 5 and an energy accumulator 6, wherein the main valve is a hydraulic control reversing valve, the pilot valve is a reversing valve, two pilot control oil ports of the main valve are respectively connected with two working oil ports of the pilot valve, a rod cavity and a rodless cavity of the oil cylinder are respectively connected with the two working oil ports of the main valve through joints, an oil return port of the main valve and an oil return port of the pilot valve are both connected with an oil tank 7, an inlet of the oil pump is connected with the oil tank, an outlet of the oil pump is connected with a driving oil path 8 and a control oil path 9, the driving oil path is connected with an oil inlet of the main valve, the control oil path is connected with an oil inlet of the pilot valve, a charging and discharging port of the energy accumulator is connected to the control oil path, the, the disassembly safety is ensured. After the oil pump stops working, when the main valve acts to enable the pipeline to be decompressed, the hydraulic oil in the pipeline flows back to the oil tank from the oil return port of the main valve.
Furthermore, a pressure reducing valve 10 is arranged on the control oil path, the pressure reducing valve is positioned at the upstream of the energy accumulator, the positive flow direction of the pressure reducing valve is the direction from the oil pump to the pilot valve and the energy accumulator, the hydraulic oil flowing out of the oil pump flows into the energy accumulator and/or the pilot valve after passing through the pressure reducing valve, and the pressure of the oil outlet is used as the control pressure by the pressure reducing valve.
Furthermore, the charge and discharge energy port of the energy accumulator is divided into two branches L and M which are connected to the control oil path 9, a first check valve 11 is arranged on the branch L, the branch M is directly connected to the control oil path, the connection point of the branch L and the control oil path is located at the upstream of the connection point of the branch M and the control oil path, a second check valve 12 is arranged on the control oil path, the second check valve is located between the branch L and the branch M, the forward flowing directions of the first check valve and the second check valve are directions far away from the oil pump, and the first check valve and the second check valve are used for preventing pressure oil of the energy accumulator from leaking to a pipeline close to the oil pump when the energy accumulator releases energy, so that enough pressure oil is used for driving the main valve.
Further, the exit linkage of oil pump has the overflow valve 13 of taking control port k, and the oil inlet of overflow valve connects the oil pump and exports, and the oil-out of overflow valve connects the oil tank, and the control port k of overflow valve communicates with each other with the e mouth of pilot valve, and the connection status of the e mouth of pilot valve is: when the pilot valve does not act, the e port and the control port K are communicated with the oil tank, the overflow valve is in an unloading state, when the pilot valve acts, the e port is stopped, the overflow valve is in a normal working state, the function of the normal overflow valve is realized, and the system works normally.
Preferably, the pilot valve is a three-position six-way reversing valve, the valve is located in a middle position when the valve does not act, the port e is communicated with the oil tank when the pilot valve does not act in the middle position, and the port e is cut off when the pilot valve acts away from the middle position.
The utility model provides a pile driver, includes pilot hydraulic control's major loop off-load system, the epicoele of hydro-cylinder is the rodless chamber, and the cavity of resorption of hydro-cylinder is for having the pole chamber, is provided with on the pipeline of hydro-cylinder epicoele and cavity of resorption business turn over oil port department and connects 4, and the cavity of resorption of hydro-cylinder is connected with stop valve 14, and the stop valve is located the pipeline between hydro-cylinder cavity of resorption business turn over oil port and the joint, and the stop valve is opened at oil pump during operation, and the stop valve is closed before the hydro-cylinder is dismantled.
The invention has at least the following beneficial effects:
the energy accumulator is arranged on the hydraulic main loop of the engineering machinery, when the oil pump stops, the energy accumulator releases energy to drive the main valve, so that oil pressure remained in a system pipeline can be discharged in time when the oil pump stops working, the safety performance of the pipeline during disassembly is effectively ensured, and the energy accumulator is very suitable for large engineering machinery which needs to be disassembled and transferred to a site, and is particularly suitable for a pile pressing machine.
In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic diagram of a main circuit of a hydraulic system of a prior art pile press;
fig. 2 is a schematic diagram of a main circuit unloading system of the hydrostatic pile press in accordance with a preferred embodiment of the present invention.
In the figure: 1-main valve, 2-pilot valve, 3-oil cylinder, 4-joint, 5-oil pump, 6-accumulator, 7-oil tank, 8-driving oil circuit, 9-control oil circuit, 10-pressure reducing valve, 11-one-way valve I, 12-one-way valve II, 13-overflow valve and 14-stop valve.
Detailed Description
Embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways, which are defined and covered by the claims.
Referring to fig. 2, the unloading system for a pilot hydraulic controlled static pile driver main loop includes an oil cylinder 3, a main valve 1, a pilot valve 2, an oil pump 5 and an energy accumulator 6, in this embodiment, the main valve is a hydraulic control directional valve, the pilot valve is a manual directional valve, two pilot control oil ports of the main valve are respectively connected to an operating oil port c and an operating oil port d of the pilot valve, a rod chamber and a rodless chamber of the oil cylinder are respectively connected to an operating oil port a and an operating oil port b of the main valve through joints, both the main valve and an oil return port of the pilot valve are connected to an oil tank 7, an inlet of the oil pump is connected to the oil tank, an outlet of the oil pump is connected to a driving oil path 8 and a control oil path 9, the driving oil path is connected to an oil inlet of the main valve, the control oil path is connected to an oil inlet of the pilot valve, a charge/discharge port of the energy accumulator, thereby the oil cylinder and the pipeline are decompressed, and the disassembly safety is ensured. After the oil pump stops working, when the main valve acts to enable the pipeline to be decompressed, the hydraulic oil in the pipeline flows back to the oil tank from the oil return port of the main valve.
In this embodiment, a pressure reducing valve 10 is disposed on the control oil path, the pressure reducing valve is located at the upstream of the energy accumulator, the forward flow direction of the pressure reducing valve is the direction from the oil pump to the pilot valve and the energy accumulator, the control oil port of the pressure reducing valve is connected to the control oil path 9, and the pressure reducing valve is used for controlling the oil pressure entering the energy accumulator and the pilot valve to prevent the oil pressure entering the energy accumulator and the pilot valve from being too large.
In this embodiment, the charge and discharge energy port of the energy accumulator is divided into two branches L and M, which are connected to the control oil path 9, a first check valve 11 is disposed on the branch L, the branch M is directly connected to the control oil path, a second check valve 12 is disposed on the control oil path, the position of the second check valve is located between the branch L and the branch M, and the forward flowing directions of the first check valve and the second check valve are directions away from the oil pump.
In this embodiment, the exit linkage of oil pump has the overflow valve 13 of taking control port k, and the oil inlet of overflow valve connects the oil pump and exports, and the oil-out of overflow valve connects the oil tank, and the control port k of overflow valve communicates with each other with the e mouth of pilot valve, and the connection status of the e mouth of pilot valve is: when the oil inlet of the pilot valve does not act, the port e and the control port K are communicated with the oil tank, the overflow valve is in an unloading state, when the pilot valve acts, the port e is stopped, the overflow valve is in a normal working state, the function of the normal overflow valve is played, and the system works normally.
In this embodiment, the pilot valve is a three-position six-way reversing valve, and is located the meso position when the pilot valve is not operated, and when the pilot valve is located the meso position, e mouthful and control mouth K communicate with each other with the oil tank, and the oil-out output pressure of overflow valve increases along with the reduction of control mouth K pressure, and when control mouth K and oil tank switch-on, the oil-out output pressure of overflow valve is the biggest, and the overflow valve is used for letting the system be in idle state when the oil pump stops working, plays the pressure release effect. When the pilot valve leaves the middle position, the e port is cut off, the control port K does not work, and the overflow valve plays a normal safety valve role.
In this embodiment, the upper chamber of the oil cylinder is a rodless chamber, the lower chamber of the oil cylinder is a rod chamber, the pipelines at the oil inlet and the oil outlet of the upper chamber and the lower chamber of the oil cylinder are provided with connectors 4 which can be flexibly detached and connected, the lower chamber of the oil cylinder is connected with a stop valve 14, the stop valve is located on the pipeline between the oil inlet and the oil outlet of the lower chamber of the oil cylinder and the connectors, the stop valve is opened when the oil pump works, and the stop valve is closed before the oil cylinder is detached.
The working process and principle of the embodiment are roughly as follows:
when the oil pump works, the pilot valve is manually switched to the left position or the right position, oil in the control oil way 9 flows out through the pressure reducing valve 10 and then is divided into two paths, one path of oil flows into the energy accumulator 6 through the one-way valve I11 on the branch L, the energy accumulator 6 stores energy, the other path of oil flows into the pilot valve 2 through the two one-way valve II 12, the oil flows into the pilot control oil port of the main valve through the left position or the right position of the pilot valve 2 to drive the main valve 1 to be changed into the right position or the left position, and the oil in the drive oil way 8 enters the lower cavity or the upper cavity of the oil cylinder 3 through the.
When the middle position function of the main valve needs to be used, the pilot valve is switched manually to return to the middle position, the oil pump is closed at the same time, the oil way of the pilot control oil port of the main valve is communicated with the return oil tank, and the main valve returns to the middle position.
When the oil cylinder needs to be disassembled, the stop valve 14 is closed first, the pilot valve is switched from the middle position to the left position manually, then the pilot valve is switched from the left position to the right position, or the middle position is switched to the right position first, then the right position is switched to the left position, and the operation is repeated for a plurality of times, when the pilot valve is positioned at the left position or the right position, the pilot control oil port of the main valve is communicated with the energy accumulator charging and discharging port, the pressure oil released by the energy accumulator flows to the pilot valve through the branch M, the pressure oil enters the pilot control oil port of the main valve through the left position or the right position of the pilot valve, the main valve obtains reversing power, the middle position is switched to the right position or the left position, the pressure oil in the pipeline partially flows back to the oil tank, the oil pressure in.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (4)

1. The pilot hydraulic control main loop unloading system is characterized by comprising an oil cylinder (3), a main valve (1), a pilot valve (2), an oil pump (5) and an energy accumulator (6), wherein the main valve is a hydraulic control reversing valve, the pilot valve is a reversing valve, two pilot control oil ports of the main valve are respectively connected with two working oil ports of the pilot valve, a rod cavity and a rodless cavity of the oil cylinder are respectively connected with the two working oil ports of the main valve through joints, the main valve is an O-shaped reversing valve with a neutral position function, an oil return port of the main valve and an oil return port of the pilot valve are both connected with an oil tank (7), an outlet of the oil pump is connected with a driving oil path (8) and a control oil path (9), the driving oil path is connected with an oil inlet of the main valve, the control oil path is connected with an oil inlet of the pilot valve, an energy charging and discharging port of the energy accumulator is connected to the control, the pilot valve provides pilot control pressure for the main valve to drive the main valve to be switched from a middle position to a right position or a left position, so that the rodless cavity and the rod cavity of the oil cylinder are communicated with the oil tank, and oil pressure in a pipeline connected with the rodless cavity and the rod cavity of the oil cylinder is timely relieved;
the exit linkage of oil pump has overflow valve (13) of taking control port k, and the oil inlet of overflow valve connects the oil pump and exports, and the oil-out of overflow valve connects the oil tank, and the control port k of overflow valve communicates with each other with the e mouth of pilot valve, and the connection status of the e mouth of pilot valve is: when the pilot valve does not act, the port e and the control port K are communicated with the oil tank, the overflow valve is in an unloading state, when the pilot valve acts, the port e is stopped, and the overflow valve is in a normal working state;
the pilot valve is a three-position six-way reversing valve, the pilot valve is positioned in a middle position when not operated, the port e is communicated with the oil tank when the pilot valve is positioned in the middle position, and the port e is stopped when the pilot valve is operated to leave the middle position;
the overflow valve is used for enabling the system to be in an idle state when the oil pump stops working, and the pressure relief effect is achieved;
the energy charging and discharging port of the energy accumulator is divided into an L branch and an M branch which are connected to a control oil way, wherein the connection point of the L branch and the control oil way is located at the upstream of the connection point of the M branch and the control oil way, a one-way valve I (11) is arranged on the L branch, the M branch is directly connected to the control oil way, a two-way valve (12) is arranged on the control oil way, the position of the two-way valve is located between the L branch and the M branch, and the forward flowing directions of the two-way valve I and the one-way valve II are directions far away from an.
2. The pilot-operated hydraulic control main circuit unloading system according to claim 1, wherein a pressure reducing valve (10) is arranged on the control oil path, the pressure reducing valve is located upstream of the accumulator, the positive flow direction of the pressure reducing valve is the direction from the oil pump to the pilot valve and the accumulator, and the pressure reducing valve takes the oil outlet pressure as the control pressure.
3. The pilot-operated hydraulic control main circuit unloader system according to claim 1 or 2, wherein when the line is depressurized by the operation of the main valve after the oil pump stops operating, the hydraulic oil in the line flows back to the tank from the return port of the main valve.
4. A pile pressing machine is characterized by comprising the pilot hydraulic control main circuit unloading system according to any one of claims 1 to 3, wherein the upper cavity of the oil cylinder is a rodless cavity, the lower cavity of the oil cylinder is a rod cavity, the pipelines at the oil inlet and outlet of the upper cavity and the lower cavity of the oil cylinder are provided with connectors (4), the lower cavity of the oil cylinder is connected with a stop valve (14), and the stop valve is positioned on the pipeline between the oil inlet and outlet of the lower cavity of the oil cylinder and the connectors.
CN201811483152.6A 2018-12-05 2018-12-05 Pilot hydraulic control main loop unloading system and pile press Active CN109281874B (en)

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CN110541449B (en) * 2019-09-19 2024-06-25 广西玉柴重工有限公司 Safety device of hydraulic excavator
CN111059089A (en) * 2020-01-09 2020-04-24 安徽合力股份有限公司 Descending energy recovery system of empty container stacking machine
CN111577714B (en) * 2020-05-18 2022-04-29 山东临工工程机械有限公司 Hydraulic system and engineering machinery
CN114087249B (en) * 2021-11-18 2023-05-26 国能神东煤炭集团有限责任公司 Electrohydraulic pressure control system and control method

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CN201380582Y (en) * 2009-04-11 2010-01-13 广东伊之密精密机械有限公司 Oil-outlet servo control device of injection molding machine
CN102418725B (en) * 2011-10-24 2013-03-20 中联重科股份有限公司 Pumping equipment and distribution hydraulic system thereof
CN102606550A (en) * 2012-03-31 2012-07-25 威海华东数控股份有限公司 Energy-saving hydraulic driving system
CN103104005A (en) * 2012-12-07 2013-05-15 青岛鲁达工程机械制造有限公司 Small-sized loader hydraulic pilot control device
CN204300036U (en) * 2014-11-11 2015-04-29 中冶陕压重工设备有限公司 Super high pressure hydraulic can fast automatic off-load shock mitigation system

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