CN111851618B - Method and system for solving problem of slow bucket collecting speed of constant-variable flow converging system - Google Patents
Method and system for solving problem of slow bucket collecting speed of constant-variable flow converging system Download PDFInfo
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- CN111851618B CN111851618B CN202010752885.6A CN202010752885A CN111851618B CN 111851618 B CN111851618 B CN 111851618B CN 202010752885 A CN202010752885 A CN 202010752885A CN 111851618 B CN111851618 B CN 111851618B
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/28—Dredgers; 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
- E02F3/36—Component parts
- E02F3/42—Drives for dippers, buckets, dipper-arms or bucket-arms
- E02F3/425—Drive systems for dipper-arms, backhoes or the like
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/28—Dredgers; 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
- E02F3/30—Dredgers; 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 with a dipper-arm pivoted on a cantilever beam, i.e. boom
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Operation Control Of Excavators (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention provides a method for solving the problem that the bucket collecting speed of a constant-variable flow converging system is reduced, which comprises the following steps: a pilot flow dividing pipeline is additionally arranged on a pipeline which is connected with a reversing valve from a pilot valve in the constant-variable flow combining system; one end of the pilot flow dividing pipeline is connected with the pilot valve, and the other end of the pilot flow dividing pipeline is connected with a valve core of a sequence valve in the confluence valve; when the pilot valve works, pilot oil acts on a valve core of the sequence valve through the pilot flow dividing pipeline; the invention acts on the sequence valve in the converging valve through the one-way valve, ensures the converging state when the system pressure is low, solves the problem that the bucket collection is slow with lower cost while the existing converging valve is not changed, keeps the speed of the bucket collection process unchanged, further shortens the bucket collection time when the loader works, and improves the working efficiency.
Description
Technical Field
The invention relates to the field of monitoring systems, in particular to a method for solving the problem that the speed of a constant variable converging system becomes slow after a hopper passes a gravity center point.
Background
The bucket of the loader rotates by pulling the rocker arm and the pull rod through the extension and retraction of the bucket oil cylinder to drive the bucket to rotate. In the constant-variable flow-combining hydraulic system, a power oil source is provided after a gear pump and a variable pump are combined through a flow-combining valve, a pilot oil source is provided by a pilot valve to push a reversing valve to reverse, and the power oil source pushes a bucket oil cylinder to move in a reversing mode through the reversing valve.
On the existing public engineering vehicle applying the constant-variable flow converging system, oil output from a plunger pump is conveyed to a flow converging valve after passing through a priority valve, the oil output from a gear pump is connected to the flow converging valve, the two pumps are converged to provide an oil source for a reversing valve, meanwhile, an LS signal is provided for the plunger pump to control the discharge capacity of the plunger pump, a pilot oil source is provided by a pilot valve to push the reversing valve to reverse, the oil source flows to a bucket oil cylinder after reversing to push the oil cylinder to act, and the oil cylinder drives the bucket to rotate through a rocker arm and a pull rod;
when the bucket is collected by using the constant-variable flow converging system, the bucket can be collected at a constant speed in the initial stage, when the gravity center of the bucket passes through a rotation center, the bucket collecting speed can be slowed down, the problem that the bucket collecting speed is slowed down can cause that the bucket collecting time is prolonged when the loader works, and the working efficiency is reduced.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a method and a system for solving the problem that the speed of a constant variable converging system after the hopper goes through a gravity center point is slow. When the bucket is collected by the constant-variable flow converging system, the bucket can be collected at a constant speed in the initial stage, after the gravity center of the bucket passes through a vertical line of a rotation center, the stress of an oil cylinder of the bucket is pulling force as shown in fig. 5, and the pressure required by a large cavity of the oil cylinder is extremely low, so that the pressure of the system is low (less than 20 bar). The valve core of the sequence valve on the left side in the confluence valve is closed due to low system pressure, oil of the plunger pump cannot be converged to the reversing valve, only the gear pump supplies oil to the system at the moment, the speed of the oil cylinder is reduced, and the bucket collecting speed is intuitively reduced. This application adopts following mode to solve the problem that receipts fill speed becomes slow:
the invention provides a method for solving the problem that the closing speed of a constant variable converging system is reduced, which comprises the following steps: a pilot flow dividing pipeline is additionally arranged on a pipeline which is connected with a reversing valve from a pilot valve in the constant-variable flow combining system;
one end of the pilot flow dividing pipeline is connected with the pilot valve, and the other end of the pilot flow dividing pipeline is connected with a valve core of a sequence valve in the confluence valve;
when the pilot valve works, pilot oil acts on the valve core of the sequence valve through the pilot flow dividing pipeline, so that the flow converging valve is in a communication position, an oil source is not influenced by system pressure and flows to the reversing valve through the flow converging valve, and the bucket collecting speed is kept unchanged.
In a second aspect, the present invention further provides a constant/variable quantity confluence system using the method of the first aspect, comprising a pilot branch pipeline, wherein one end of the pilot branch pipeline is connected with a pilot valve, and the other end of the pilot branch pipeline is connected with a valve core of a sequence valve in a confluence valve; when the pilot valve works, pilot oil acts on the valve core of the sequence valve through the pilot flow dividing pipeline.
Compared with the prior art, the invention has the following beneficial effects:
1. the invention utilizes pilot oil to divide pressure oil, and the pressure oil is acted on the sequence valve in the flow-merging valve through the one-way valve, thereby ensuring the flow-merging state when the system pressure is low, and solving the problem that the bucket collection is slow with lower cost while the existing flow-merging valve is not changed.
2. At present, the plunger pump and the gear pump are combined to supply oil, the oil supply speed of the oil cylinder is sufficient and normal, and the pressure is reduced after the gravity center of the bucket passes through a hinge point, so that the plunger pump does not supply oil any more, only the gear pump supplies oil, and the speed is reduced due to the reduction of the oil quantity; the pilot oil source acts on the sequential valve core to force the sequential valve core to be in a confluence state, so that the plunger pump and the gear pump supply oil simultaneously, the speed is kept unchanged, the problem that the bucket retracting speed is reduced due to the fact that the oil amount is reduced after the gravity center of the bucket passes through the rotation center is solved, the bucket retracting time of the loader during operation is shortened, and the working efficiency is improved.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.
FIG. 1 is a schematic structural diagram of a constant variable converging system adopting a method for solving the problem of slowing down of a closing speed, which is provided by the invention;
FIG. 2 is a schematic view of a flow converging valve of a constant variable flow converging system adopting a method for solving the problem of slowing down of the bucket collecting speed, which is provided by the invention;
FIG. 3 is a schematic view of the flow direction of an oil source of a constant variable converging system adopting a method for solving the problem of slowing down the closing speed according to the present invention;
FIG. 4 is a diagram illustrating a bucket structure of a construction vehicle employing a constant/variable confluence system according to the prior art;
FIG. 5 is a bucket diagram of a construction vehicle employing a fixed variable flow combining system according to the prior art;
FIG. 6 is a schematic structural diagram of a related art constant variable confluence system;
fig. 7 is a schematic structural diagram of a confluence valve using a constant variable confluence system in the background art.
The specific implementation mode is as follows:
the invention is further described with reference to the following figures and examples.
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
In the present invention, terms such as "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "side", "bottom", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only terms of relationships determined for convenience of describing structural relationships of the parts or elements of the present invention, and are not intended to refer to any parts or elements of the present invention, and are not to be construed as limiting the present invention.
In the present invention, terms such as "fixedly connected", "connected", and the like are to be understood in a broad sense, and may be a fixed connection, or may be an integral connection or a detachable connection; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be determined according to specific situations by persons skilled in the relevant scientific or technical field, and are not to be construed as limiting the present invention.
Example 1
The invention solves the problem that the oil cylinder becomes slow in the moving process: the plunger pump and the gear pump are started to perform confluence oil supply, the oil supply speed of the oil cylinder is sufficient and normal, and the pressure is reduced after the hinge point is crossed at the gravity center of the bucket, so that the plunger pump does not supply oil any more, only the gear pump supplies oil, and the oil quantity is reduced to slow down the speed. The invention forces the sequential valve core to be in a confluence state by the action of the pilot oil source on the sequential valve core, thereby simultaneously supplying oil to the plunger pump and the gear pump and keeping the speed unchanged.
A method for solving the problem that the bucket collecting speed of a constant variable flow converging system is reduced comprises the following steps:
a pilot flow dividing pipeline is additionally arranged on a pipeline which is connected with a reversing valve from a pilot valve in the constant-variable flow combining system;
one end of the pilot flow dividing pipeline is connected with the pilot valve, and the other end of the pilot flow dividing pipeline is connected with a valve core of a sequence valve in the confluence valve;
when the pilot valve works, pilot oil acts on the valve core of the sequence valve through the pilot flow dividing pipeline, so that the flow converging valve is in a communication position, an oil source is not influenced by system pressure and flows to the reversing valve through the flow converging valve, and the bucket collecting speed is kept unchanged.
Further, the pilot flow dividing pipeline is provided with a one-way valve.
Furthermore, when the pilot valve acts, the pilot oil pushes the reversing valve core to reverse and collect the hopper, and meanwhile, the pilot oil is divided into partial pressure oil through the pilot flow dividing pipeline and acts on the valve core of the sequence valve in the flow merging valve after passing through the one-way valve.
Furthermore, when the constant variable flow converging system starts to collect the hopper, the system pressure is high, high-pressure oil acts on a valve core of a sequence valve in the flow converging valve to enable the flow converging valve to be in a communicating position, and the high-pressure oil is blocked by the one-way valve and cannot interfere with a pilot oil way.
Furthermore, when the constant variable converging system receives the bucket to the rotating center, the system pressure is reduced, the pilot oil pressure is higher than the system pressure, the pilot oil passes through the one-way valve and then acts on the valve core of the sequence valve, the converging valve is pushed to be in a communicating position, the oil source of the plunger pump can pass through the converging valve to the reversing valve, and the bucket receiving speed is kept unchanged.
Furthermore, the fixed-variable confluence system adopts a plunger pump to discharge oil, the oil is conveyed to a confluence valve through a priority valve, the oil discharged by a gear pump is connected to the confluence valve, the two pumps are converged to provide a confluence oil source for a reversing valve, and meanwhile, a control system sends an LS signal to the plunger pump, wherein the LS signal is a feedback signal and controls the discharge capacity of the plunger pump.
Furthermore, the pilot valve provides a pilot oil source to push the reversing valve to reverse, after reversing, the combined oil source flows to the bucket oil cylinder to push the oil cylinder to act, and the oil cylinder drives the bucket to rotate through the rocker arm and the pull rod.
Specifically, oil output from the plunger pump is conveyed to the flow merging valve after passing through the priority valve, oil output from the gear pump is connected to the flow merging valve, an oil source is provided for the reversing valve after the two pumps are merged, an LS signal is provided for the plunger pump to control the displacement of the plunger pump, a pilot oil source is provided by the pilot valve to push the reversing valve to reverse, the reversed oil source flows to the bucket oil cylinder to push the oil cylinder to act, and the oil cylinder drives the bucket to rotate through the rocker arm and the pull rod.
As shown in fig. 4: a pipeline is divided from a pipeline of the pilot valve connected with the reversing valve, and the pipeline is connected with a one-way valve and then connected to a valve core of a sequence valve in the flow combination valve. When the pilot valve acts, pilot oil pushes the reversing valve core to reverse and collect the hopper, and part of pressure oil is divided and acts on the valve core of the sequence valve in the flow merging valve after passing through the one-way valve.
When the bucket begins to be collected, the system pressure is high, high-pressure oil acts on the valve core of the sequence valve in the flow-merging valve, the flow-merging valve is in a communicating position, and the high-pressure oil is blocked by the one-way valve and does not interfere with a pilot oil way. When the bucket is collected to the rotation center, the system pressure is reduced, the pilot oil pressure is higher than the system pressure, the pilot oil passes through the one-way valve and then acts on the valve core of the sequence valve, the confluence valve is pushed to be in a communication position, an oil source of the plunger pump can pass through the confluence valve to the reversing valve (as shown in figure 5), and the bucket collecting speed is kept unchanged.
Also provided in other embodiments are:
the constant-variable flow converging system adopting the method in the embodiment 1 comprises a pilot flow dividing pipeline, wherein one end of the pilot flow dividing pipeline is connected with a pilot valve, and the other end of the pilot flow dividing pipeline is connected with a valve core of a sequence valve in a flow converging valve; when the pilot valve works, pilot oil acts on the valve core of the sequence valve through the pilot flow dividing pipeline.
Further, the pilot flow dividing pipeline is provided with a one-way valve.
Furthermore, the constant-variable flow converging system also comprises a plunger pump, a priority valve, a flow converging valve, a gear pump and a control system; an oil outlet pipeline of the plunger pump is connected with a first oil inlet pipeline of the confluence valve after passing through the priority valve, and an oil outlet pipeline of the gear pump is connected with a second oil inlet pipeline of the confluence valve; the oil outlet pipeline of the flow merging valve is connected with the oil inlet pipeline of the reversing valve; the control system is connected with the plunger pump and used for transmitting the LS signal and controlling the displacement of the plunger pump.
Furthermore, an oil outlet pipeline of the reversing valve is connected with the bucket cylinder; the pilot valve provides a pilot oil source to push the reversing valve to reverse, after reversing, the combined oil source flows to the bucket oil cylinder to push the oil cylinder to act, and the oil cylinder drives the bucket to rotate through the rocker arm and the pull rod.
Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.
Claims (8)
1. A method for solving the problem that the bucket collecting speed of a constant variable flow converging system is reduced is characterized by comprising the following steps:
a pilot flow dividing pipeline is additionally arranged on a pipeline which is connected with a reversing valve from a pilot valve in the constant-variable flow combining system;
one end of the pilot flow dividing pipeline is connected with the pilot valve, and the other end of the pilot flow dividing pipeline is connected with a valve core of a sequence valve in the confluence valve;
when the pilot valve works, pilot oil acts on a valve core of the sequence valve through the pilot flow dividing pipeline to enable the flow merging valve to be in a communication position, an oil source is not influenced by system pressure and flows to the reversing valve through the flow merging valve, and the bucket collecting speed is kept unchanged;
the pilot flow dividing pipeline is provided with a one-way valve; when the constant-variable converging system is collected to the rotating center, the system pressure is reduced, the pilot oil pressure is higher than the system pressure, the pilot oil passes through the one-way valve and then acts on the valve core of the sequence valve to push the converging valve to be in a communicating position, and the oil source of the plunger pump can pass through the converging valve to the reversing valve to keep the collecting speed unchanged.
2. The method for solving the problem of slow bucket-closing speed of the constant-variable flow converging system as claimed in claim 1, wherein when the pilot valve is actuated, the pilot oil pushes the reversing valve core to reverse the bucket-closing, and meanwhile, the pilot oil is divided into partial pressure oil through the pilot flow dividing pipeline and acts on the valve core of the sequence valve in the flow converging valve after passing through the one-way valve.
3. The method for solving the problem of slow bucket collecting speed of the constant-variable confluence system as claimed in claim 1, wherein when the constant-variable confluence system starts to collect the bucket, the system pressure is high, high-pressure oil acts on the valve core of the sequence valve in the confluence valve to enable the confluence valve to be in a communicating position, and the high-pressure oil is blocked by the one-way valve and does not interfere with the pilot oil path.
4. The method for solving the problem of slow bucket collecting speed of the constant-variable confluence system as claimed in claim 1, wherein the constant-variable confluence system adopts a plunger pump to pump the oil out, pass through a priority valve and then deliver the oil to a confluence valve, a gear pump is connected with the confluence valve, and the two pumps are converged to provide a confluence oil source for a reversing valve; the control system sends an LS signal to the plunger pump and controls the displacement of the plunger pump.
5. The method for solving the problem of slow bucket retracting speed of the constant-variable flow converging system as claimed in claim 4, wherein the pilot valve provides a pilot oil source to push the reversing valve to reverse, after reversing, the converging oil source flows to the bucket oil cylinder to push the oil cylinder to act, and the oil cylinder drives the bucket to rotate through the rocker arm and the pull rod.
6. A constant-variable confluence system using the method as claimed in any one of claims 1 to 5, comprising a pilot split line having one end connected to the pilot valve and the other end connected to the spool of the sequence valve in the confluence valve; when the pilot valve works, pilot oil acts on the valve core of the sequence valve through the pilot flow dividing pipeline.
7. A constant-variable confluence system according to claim 6 wherein said pilot split conduit is provided with a check valve.
8. The fixed-variable confluence system of claim 6 wherein said fixed-variable confluence system comprises a plunger pump, a priority valve, a confluence valve, a gear pump, and a control system; an oil outlet pipeline of the plunger pump is connected with a first oil inlet pipeline of the confluence valve after passing through the priority valve, and an oil outlet pipeline of the gear pump is connected with a second oil inlet pipeline of the confluence valve; the oil outlet pipeline of the flow merging valve is connected with the oil inlet pipeline of the reversing valve; the control system is connected with the plunger pump and used for transmitting the LS signal and controlling the displacement of the plunger pump.
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JPS57165537A (en) * | 1981-04-07 | 1982-10-12 | Hitachi Constr Mach Co Ltd | Rotary oil-pressure circuit for construction machinery |
KR101088752B1 (en) * | 2009-05-22 | 2011-12-01 | 볼보 컨스트럭션 이큅먼트 에이비 | hydraulic system with improvement complex operation |
CN105317067B (en) * | 2015-11-30 | 2018-06-19 | 周驰军 | A kind of outer converging system of double pump valve suitable for digging machine disintegrating hammer |
CN208816427U (en) * | 2018-08-23 | 2019-05-03 | 山推工程机械股份有限公司 | Close flux controllable loader dual-pump combining hydraulic system |
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Address after: No.75, Huanghe East Road, Huangdao District, Qingdao City, Shandong Province 266599 Patentee after: Lovol Heavy Industry Group Co.,Ltd. Address before: No.75, Huanghe East Road, Huangdao District, Qingdao City, Shandong Province 266599 Patentee before: LOVOL Engineering Machinery Group Co.,Ltd. |