CN111156210A - Pumping oil cylinder control system and control method for concrete pump - Google Patents
Pumping oil cylinder control system and control method for concrete pump Download PDFInfo
- Publication number
- CN111156210A CN111156210A CN202010231063.3A CN202010231063A CN111156210A CN 111156210 A CN111156210 A CN 111156210A CN 202010231063 A CN202010231063 A CN 202010231063A CN 111156210 A CN111156210 A CN 111156210A
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- oil cylinder
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- valve
- variable
- pumping oil
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- 238000005086 pumping Methods 0.000 title claims abstract description 56
- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000006073 displacement reaction Methods 0.000 claims abstract description 19
- 230000007246 mechanism Effects 0.000 claims abstract description 18
- 230000008569 process Effects 0.000 claims abstract description 6
- 230000003111 delayed effect Effects 0.000 claims description 2
- 230000008859 change Effects 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Classifications
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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
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
- F15B11/166—Controlling a pilot pressure in response to the load, i.e. supply to at least one user is regulated by adjusting either the system pilot pressure or one or more of the individual pilot command pressures
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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
- F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more 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
- 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
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Reciprocating Pumps (AREA)
Abstract
A control system and a control method for a pumping oil cylinder of a concrete pump comprise a variable pump (1), an electro-hydraulic directional valve (10), a first pumping oil cylinder (11), a second pumping oil cylinder (12), a first proximity switch (SQ 1), a second proximity switch (SQ 2) and a control mechanism for controlling the variable pump; the control process comprises the following steps: the electro-hydraulic reversing valve (10) is in a left position, the second pumping oil cylinder (12) is retracted and then touches a second proximity switch (SQ 2), the electro-hydraulic reversing valve is switched to a middle position for unloading, and the PWM controller controls the displacement of the variable displacement pump to be 0; after a period of time delay, the electro-hydraulic directional valve (10) is switched to the right position, and the variable pump (1) starts to ramp up the flow; after the first pumping oil cylinder (11) retracts and touches a first proximity switch (SQ 1), the electro-hydraulic reversing valve (10) is switched to a middle position for unloading, meanwhile, the PWM controller controls the displacement of the variable pump (1) to be 0, after a period of delay, the electro-hydraulic reversing valve (10) is switched to a left position, and the variable pump (1) starts to rise the flow in a slope mode.
Description
Technical Field
The invention relates to the technical field of concrete pumps, in particular to a control system of a pumping oil cylinder for a concrete pump, and further relates to a control method of the pumping oil cylinder for the concrete pump.
Background
The concrete pump is mostly a double-pump double-loop electro-hydraulic combined control hydraulic system. When the oil cylinder reaches the head, the reversing action of the oil cylinder is realized through the switching of the reversing valve or the oil pump swash plate. When a concrete pump or a vehicle-mounted concrete pump is in a normal pumping process and is switched to a middle position instantly, the hydraulic impact generated by instant release of high-pressure oil and large-flow oil is huge; the instantaneous high-speed motion of the oil cylinder and the concrete form collision to generate huge structural impact. Impact and vibration can affect the positioning accuracy of the piston head, shorten the service life of the equipment and prevent the normal operation of the equipment.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a control system and a control method for a pumping oil cylinder for a concrete pump, which can solve the technical defects.
In order to solve the technical problems, on one hand, the invention provides a pumping oil cylinder control system for a concrete pump, which comprises a variable pump and a control mechanism for controlling the variable pump, wherein the control mechanism comprises a variable oil cylinder and a reset oil cylinder, an adjusting piston communicated with a rod cavity of the reset oil cylinder, a variable control valve connected with a connecting rod of the adjusting piston, a pressure control valve, a proportional electromagnet control valve, a shuttle valve connected with the variable control valve, the pressure control valve and the proportional electromagnet control valve, and a PWM controller for controlling the control mechanism; the pumping oil cylinder control system for the concrete pump further comprises an electro-hydraulic reversing valve communicated with an outlet of the variable pump, a first pumping oil cylinder and a second pumping oil cylinder communicated with working oil ports of the electro-hydraulic reversing valve, a first proximity switch for detecting whether the first pumping oil cylinder retracts or not, and a second proximity switch for detecting whether the second pumping oil cylinder retracts or not, wherein the first proximity switch and the second proximity switch are respectively and electrically connected with two electromagnetic valve coils of the electro-hydraulic reversing valve.
In order to solve the technical problem, on the other hand, the invention provides a method for controlling a pumping oil cylinder for a concrete pump, wherein the concrete pump is provided with an electro-hydraulic control system for controlling the pumping oil cylinder, the electro-hydraulic control system comprises a variable pump and a control mechanism for controlling the variable pump, the control mechanism comprises a variable oil cylinder and a reset oil cylinder, an adjusting piston communicated with a rod cavity of the reset oil cylinder, a variable control valve connected with a connecting rod of the adjusting piston, a pressure control valve and a proportional electromagnet control valve, a shuttle valve connected with the variable control valve, the pressure control valve and the proportional electromagnet control valve, and a PWM controller for controlling the control mechanism; the control system of the pumping oil cylinder for the concrete pump further comprises an electro-hydraulic reversing valve communicated with an outlet of the variable pump, a first pumping oil cylinder and a second pumping oil cylinder communicated with a working oil port of the electro-hydraulic reversing valve, a first proximity switch for detecting whether the first pumping oil cylinder retracts or not, and a second proximity switch for detecting whether the second pumping oil cylinder retracts or not, wherein the first proximity switch and the second proximity switch are respectively and electrically connected with two electromagnetic valve coils of the electro-hydraulic reversing valve; the control process comprises the following steps:
the electro-hydraulic reversing valve is switched to the left position, the first pumping oil cylinder pushes out, the second pumping oil cylinder retracts, the second pumping oil cylinder touches a second proximity switch after retracting, the electro-hydraulic reversing valve is switched to the middle position for unloading, and meanwhile, the PWM controller controls the displacement of the variable pump to be 0, so that unloading and oil return impact are reduced; after a period of time is delayed, after the electro-hydraulic reversing valve is switched to the right position, the variable pump starts to increase the flow in a slope, the flow gradually rises, the oil inlet speed is increased in a slope mode, and unloading and oil return impact are reduced; the first pumping oil cylinder contacts a first proximity switch after retracting, the electro-hydraulic reversing valve is switched to a middle position for unloading, and meanwhile, the PWM controller controls the displacement of the variable pump to be 0, so that unloading and oil return impact are reduced; after a period of time delay, after the electro-hydraulic reversing valve is switched to the left position, the variable pump starts to increase the flow in a slope, the flow gradually rises, the oil inlet speed is increased in a slope mode, and unloading and oil return impact are reduced.
The invention has the beneficial effects that: constant power control is used to regulate the operating pressure and the output flow of the pump so that a predetermined drive power is not exceeded at a constant drive speed, thereby driving equipment, such as a diesel engine, to protect the diesel engine from stalling. The electro-hydraulic reversing valve is adopted for smooth reversing, the reversing time is long, the variable pump starts to increase the flow in a slope when the electro-hydraulic reversing valve reverses, and the flow gradually rises, so that structural impact generated by collision between instant high-speed motion of the oil cylinder and concrete can be overcome, the balance is realized in the operation process, and the equipment is protected.
Drawings
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this application, but are not intended to limit the invention. In the drawings:
FIG. 1 is a schematic diagram illustrating the control principle of a pumping cylinder control system for a concrete pump according to an embodiment.
Detailed Description
Embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.
The pumping cylinder control system for the concrete pump as shown in fig. 1 comprises a variable pump 1, a control mechanism for controlling the output of the variable pump 1, the control mechanism comprises a variable cylinder 2 and a reset cylinder 3, an adjusting piston 4 communicated with a rod cavity of the reset cylinder 3, a variable control valve 6 connected with a connecting rod of the adjusting piston 4, a pressure control valve 7 and a control valve 8 with a proportional electromagnet, a shuttle valve 9 connected with the variable control valve 6, the pressure control valve 7 and the control valve 8 with the proportional electromagnet, and a PWM controller for controlling the control mechanism; the pumping oil cylinder control system for the concrete pump further comprises an electro-hydraulic directional valve 10 communicated with an outlet of the variable displacement pump 1, a first pumping oil cylinder 11 and a second pumping oil cylinder 12 communicated with a working oil port of the electro-hydraulic directional valve 10, a first proximity switch SQ1 for detecting whether the first pumping oil cylinder 11 retracts or not, a second proximity switch SQ2 for detecting whether the second pumping oil cylinder 12 retracts or not, and the first proximity switch SQ1 and the second proximity switch SQ2 are respectively and electrically connected with two electromagnetic valve coils of the electro-hydraulic directional valve 10; the pressure control valve 7 is arranged in the control valve shell and is integrated. The control process comprises the following steps: the electro-hydraulic directional valve 10 is switched to the left position, the first pumping oil cylinder 11 is pushed out, the second pumping oil cylinder 12 retracts, the second pumping oil cylinder 12 contacts a second proximity switch SQ2 after retracting, the electro-hydraulic directional valve 10 is switched to the middle position for unloading, meanwhile, the PWM controller controls the displacement of the variable displacement pump 1 to be 0, and unloading and oil return impact are reduced; after delaying a period of time (for example, 200 milliseconds), after the electro-hydraulic reversing valve 10 is switched to the right position, the PWM controller controls the proportional electromagnet control valve 8 to control the variable pump 1 to start the ramp flow rate rise, the flow rate gradually rises from the minimum value to a constant value or a maximum value, the oil inlet speed is increased gradually at a constant speed, and unloading and oil return impact are reduced; the first pumping oil cylinder 11 is retracted and then collides with a first proximity switch SQ1, the electro-hydraulic directional valve 10 is switched to a middle position for unloading, and meanwhile, the PWM controller controls the displacement of the variable displacement pump 1 to be 0, so that unloading and oil return impact are reduced; after delaying for a period of time, after the electro-hydraulic reversing valve 10 is switched to the left position, the variable pump 1 starts to increase the flow in a slope manner, the flow gradually rises, the oil inlet speed is increased gradually at a constant speed, and unloading and oil return impact are reduced.
The working principle is as follows: the working pressure and the output flow of the pump are controlled and adjusted by adopting constant power, the preset driving power is not exceeded under the constant driving rotating speed, the working pressure exerts a force on the adjusting piston 4, the adjusting piston 4 is controlled to push the rocker arm 5, and a spring force which can be adjusted from the outside acts on the other side of the rocker arm 5 to determine the power set value. If the working pressure exceeds the set spring force, the variable control valve 6 is operated by the rocker arm, swinging the variable pump 1 towards zero output. The effective torque on the rocker arm 5 is reduced, thereby increasing the working pressure at the same rate that the output flow is reduced. The control valve 8 with the proportional electromagnet enables the displacement of the variable displacement pump 1 to be set in a stepless and programmable manner, the control of the displacement of the variable displacement pump 1 is formal with the electromagnetic force (current intensity), and the control force on the control piston is controlled by the control valve 8 with the proportional electromagnet. The constant power control is used, namely, the constant pressure control is used, when a preset pressure value is reached, the pump is swung back to the maximum flow, and the function is prior to the constant power control, namely, the constant power control is acted when the pressure is lower than the preset pressure. The electro-hydraulic directional valve 10 is stable in direction change and long in direction change time, and mainly comprises an electromagnetic directional valve and a hydraulic directional valve, wherein the electromagnetic directional valve plays a role of a pilot valve, and the hydraulic directional valve plays a role of a main valve.
It is obvious that the present invention is not limited to the above preferred embodiments, and various changes and modifications can be made within the spirit of the present invention defined by the claims and the specification, so that the same technical problems can be solved and the intended technical effects can be obtained, and thus, they are not repeated. All solutions which can be directly or indirectly derived from the disclosure of the present invention by a person skilled in the art are within the spirit of the present invention as defined by the appended claims.
Claims (2)
1. A pumping oil cylinder control system for a concrete pump comprises a variable pump (1) and a control mechanism for controlling the variable pump, wherein the control mechanism comprises a variable oil cylinder (2), a reset oil cylinder (3), an adjusting piston (4) communicated with a rod cavity of the reset oil cylinder (3) and a variable control valve (6) connected with a connecting rod of the adjusting piston (4), and is characterized in that the control mechanism is also provided with a pressure control valve (7), a proportional electromagnet control valve (8), a shuttle valve (9) connected with the variable control valve (6), the pressure control valve (7) and the proportional electromagnet control valve (8), and a PWM controller for controlling the control mechanism; the pumping oil cylinder control system for the concrete pump further comprises an electro-hydraulic directional valve (10) communicated with an outlet of the variable displacement pump (1), a first pumping oil cylinder (11) and a second pumping oil cylinder (12) communicated with a working oil port of the electro-hydraulic directional valve (10), a first proximity switch (SQ 1) for detecting whether the first pumping oil cylinder (11) retracts, a second proximity switch (SQ 2) for detecting whether the second pumping oil cylinder (12) retracts, and the first proximity switch (SQ 1) and the second proximity switch (SQ 2) are electrically connected with two electromagnetic valve coils of the electro-hydraulic directional valve (10) respectively.
2. A control method of a pumping oil cylinder for a concrete pump is characterized in that the concrete pump is provided with an electro-hydraulic control system for controlling the pumping oil cylinder, the electro-hydraulic control system comprises a variable pump (1) and a control mechanism for controlling the variable pump, the control mechanism comprises a variable oil cylinder (2) and a reset oil cylinder (3), an adjusting piston (4) communicated with a rod cavity of the reset oil cylinder (3), and a variable control valve (6) connected with a connecting rod of the adjusting piston (4), and the control mechanism is characterized by further comprising a pressure control valve (7), a proportional electromagnet control valve (8), a shuttle valve (9) connected with the variable control valve (6), the pressure control valve (7) and the proportional electromagnet control valve (8), and a PWM controller for controlling the control mechanism; the pumping oil cylinder control system for the concrete pump further comprises an electro-hydraulic directional valve (10) communicated with an outlet of the variable displacement pump (1), a first pumping oil cylinder (11) and a second pumping oil cylinder (12) communicated with a working oil port of the electro-hydraulic directional valve (10), a first proximity switch (SQ 1) for detecting whether the first pumping oil cylinder (11) retracts, a second proximity switch (SQ 2) for detecting whether the second pumping oil cylinder (12) retracts, and the first proximity switch (SQ 1) and the second proximity switch (SQ 2) are respectively and electrically connected with two electromagnetic valve coils of the electro-hydraulic directional valve (10); the control process comprises the following steps:
the electro-hydraulic directional valve (10) is switched to a left position, the first pumping oil cylinder (11) is pushed out, the second pumping oil cylinder (12) retracts, the second pumping oil cylinder (12) touches a second proximity switch (SQ 2) after retracting, the electro-hydraulic directional valve (10) is switched to a middle position for unloading, and meanwhile, the PWM controller controls the displacement of the variable displacement pump (1) to be 0, so that unloading and oil return impact are reduced; after a period of time is delayed, after the electro-hydraulic reversing valve (10) is switched to the right position, the variable pump (1) starts to increase the flow in a slope, the flow gradually rises, the oil inlet speed is increased in a slope mode, and unloading and oil return impact are reduced; the first pumping oil cylinder (11) is retracted and then collides with a first proximity switch (SQ 1), the electro-hydraulic reversing valve (10) is switched to a middle position for unloading, and meanwhile, the PWM controller controls the displacement of the variable pump (1) to be 0, so that unloading and oil return impact are reduced; after a period of time delay, after the electro-hydraulic reversing valve (10) is switched to the left position, the variable pump (1) starts to rise in the slope, the flow rises gradually, the oil inlet speed is increased gradually in the slope, and unloading and oil return impact are reduced.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010231063.3A CN111156210A (en) | 2020-03-27 | 2020-03-27 | Pumping oil cylinder control system and control method for concrete pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010231063.3A CN111156210A (en) | 2020-03-27 | 2020-03-27 | Pumping oil cylinder control system and control method for concrete pump |
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| Publication Number | Publication Date |
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| CN111156210A true CN111156210A (en) | 2020-05-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010231063.3A Pending CN111156210A (en) | 2020-03-27 | 2020-03-27 | Pumping oil cylinder control system and control method for concrete pump |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113339340A (en) * | 2021-07-08 | 2021-09-03 | 湖南拓沃重工科技有限公司 | Control system of stirring trailer pump |
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|---|---|---|---|---|
| DE59407096D1 (en) * | 1993-09-07 | 1998-11-19 | Putzmeister Ag | HYDRAULIC PRESSURE SUPPLY AND CONTROL UNIT FOR A CAR CONCRETE PUMP |
| CN101858368A (en) * | 2010-05-13 | 2010-10-13 | 山东泰丰液压设备有限公司 | Multiple directional control valve system for return oil throttle control with load sensitive pressure compensation |
| CN201687787U (en) * | 2010-05-25 | 2010-12-29 | 中铁轨道系统集团有限公司 | Concrete pump hydraulic system for conveying high-viscosity concrete |
| CN102996391A (en) * | 2012-12-03 | 2013-03-27 | 中联重科股份有限公司 | Load-sensitive pump, load-sensitive hydraulic system and concrete pumping equipment |
| CN203702702U (en) * | 2013-11-25 | 2014-07-09 | 中联重科股份有限公司 | Hydraulic control system and concrete pumping equipment |
| CN104563856A (en) * | 2015-01-15 | 2015-04-29 | 山河智能装备股份有限公司 | Quick soil throwing control system for rotary drilling rig |
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-
2020
- 2020-03-27 CN CN202010231063.3A patent/CN111156210A/en active Pending
Patent Citations (7)
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|---|---|---|---|---|
| DE59407096D1 (en) * | 1993-09-07 | 1998-11-19 | Putzmeister Ag | HYDRAULIC PRESSURE SUPPLY AND CONTROL UNIT FOR A CAR CONCRETE PUMP |
| CN101858368A (en) * | 2010-05-13 | 2010-10-13 | 山东泰丰液压设备有限公司 | Multiple directional control valve system for return oil throttle control with load sensitive pressure compensation |
| CN201687787U (en) * | 2010-05-25 | 2010-12-29 | 中铁轨道系统集团有限公司 | Concrete pump hydraulic system for conveying high-viscosity concrete |
| CN102996391A (en) * | 2012-12-03 | 2013-03-27 | 中联重科股份有限公司 | Load-sensitive pump, load-sensitive hydraulic system and concrete pumping equipment |
| CN203702702U (en) * | 2013-11-25 | 2014-07-09 | 中联重科股份有限公司 | Hydraulic control system and concrete pumping equipment |
| CN104563856A (en) * | 2015-01-15 | 2015-04-29 | 山河智能装备股份有限公司 | Quick soil throwing control system for rotary drilling rig |
| CN105134578A (en) * | 2015-07-30 | 2015-12-09 | 徐州重型机械有限公司 | Plunger pump with energy recycling function |
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| Title |
|---|
| 叶鑫: "混凝土泵泵送系统液压冲击抑制方法研究", 《中国优秀硕士学位论文全文数据库工程科技Ⅱ辑》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113339340A (en) * | 2021-07-08 | 2021-09-03 | 湖南拓沃重工科技有限公司 | Control system of stirring trailer pump |
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Application publication date: 20200515 |
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