CN116815586A - Paver and paving control method - Google Patents
Paver and paving control method Download PDFInfo
- Publication number
- CN116815586A CN116815586A CN202310750528.XA CN202310750528A CN116815586A CN 116815586 A CN116815586 A CN 116815586A CN 202310750528 A CN202310750528 A CN 202310750528A CN 116815586 A CN116815586 A CN 116815586A
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- state
- paving
- lifting
- switching valve
- cavity
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- 238000000034 method Methods 0.000 title claims abstract description 12
- 230000001276 controlling effect Effects 0.000 claims description 25
- 230000002596 correlated effect Effects 0.000 claims description 4
- 230000001105 regulatory effect Effects 0.000 claims description 4
- 238000010276 construction Methods 0.000 abstract description 4
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 239000000463 material Substances 0.000 description 7
- 239000010426 asphalt Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- 238000007373 indentation Methods 0.000 description 4
- 230000007613 environmental effect Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C19/00—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving
- E01C19/22—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving for consolidating or finishing laid-down unset materials
- E01C19/42—Machines for imparting a smooth finish to freshly-laid paving courses other than by rolling, tamping or vibrating
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- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Road Paving Machines (AREA)
Abstract
The invention discloses a paver and a paving control method. When the paver is switched from a paving stopping state to a normal paving state, the paving controller controls the state switching valve to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state, and after the first set time, the paving controller controls the state switching valve to enable the descending cavity of the lifting oil cylinder to be in a locking state, the lifting cavity to be in the non-pressure state or the locking state and controls the paver to start paving; after the second set time, the paving controller controls the state switching valve to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state. The paving control method is beneficial to avoiding the phenomenon of starting and lifting the pavement and ensuring the pavement construction quality.
Description
Technical Field
The invention relates to a paver and a paving control method, and belongs to the technical field of pavement construction machinery.
Background
The paver is special construction equipment for paving base stable materials and surface asphalt mixed materials of roads, municipal roads and the like of various grades, and has great influence on the construction quality of the pavement. The paver includes a main machine, screed and boom, and in most cases also an automatic leveling system. The main machine is used for providing power and pulling the screed plate to advance, and the big arm is hinged with the main machine and is connected with the screed plate at the rear, and the screed plate is used for preliminarily compacting, trowelling and finally forming the pavement. The main machine also generally comprises a leveling oil cylinder and a lifting oil cylinder, wherein the leveling oil cylinder is used for adjusting the height of a hinge point of the large arm and the main machine, and the lifting oil cylinder is used for lifting or lowering the screed.
The paver generally adopts a floating paving principle, namely under a normal paving working condition, two cavities of the lifting oil cylinder are communicated and are in a non-pressure state (namely, no pressure difference exists relative to atmospheric pressure), and the screed is in a balanced state under the actions of dead weight, traction force, material acting force and the like. The automatic leveling system comprises a leveling sensor and a leveling controller, wherein the leveling sensor can detect the height deviation of the screed relative to a leveling reference, and the leveling controller receives the height deviation signal detected by the leveling sensor and finally controls the height of the screed by controlling a leveling oil cylinder so as to ensure the paving thickness and the flatness.
It is well known to those skilled in the art that when a paver is in a stopped state of paving (the forward speed is 0 but the paver still has a control function) due to a waiting skip or the like during paving, a road surface is liable to be subject to stop impression and affect the final quality of the road surface. The most common solution in the industry is to put the lifting chamber of the lifting cylinder in a locked state when the paving is stopped, but the shutdown indentation phenomenon cannot be completely eliminated.
Chinese patent No. CN202110858811.5 proposes a method of reducing the downtime impression by applying pressure in the lift chamber of the lift cylinder when the paver is in a paving-stopped state. Further research shows that although the method can better eliminate shutdown indentation, the pressure applied by the lifting cavity of the lifting oil cylinder can cause the change of the posture of the host machine when the paving is stopped, and the change of the posture of the host machine can cause the starting and lifting phenomenon when the paving machine starts to pave again, which is unfavorable for the final forming quality of the pavement.
Disclosure of Invention
The invention aims to provide a paver and a paving control method, when the paver is switched to a normal paving state, the states of a lifting cavity and a descending cavity of a lifting oil cylinder are changed through a state switching valve, so that the phenomenon of starting and lifting is avoided, and the final forming quality of a pavement is improved.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the invention provides a paver, which comprises a host machine, a screed plate, a large arm, a lifting oil cylinder, a state switching valve and a paving controller, wherein the state switching valve is arranged on the host machine;
the state switching valve is used for changing the state of a lifting cavity and a descending cavity of the lifting oil cylinder;
the paving controller is used for controlling the power supply of the state switching valve and controlling the paving machine to perform paving;
the paving control apparatus is particularly useful for,
when the paving state is switched from the paving stopping state to the normal paving state, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state;
after the first set time, controlling the state switching valve to enable the descending cavity of the lifting oil cylinder to be in a locking state, enable the lifting cavity to be in a non-pressure state or a locking state, and controlling the paver to start paving;
after the second set time, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state.
Further, the first set time is a preset value.
Further, the second set time is inversely related to the paving speed.
Further, the second set time is positively correlated with the time when the paver is in a paving stop state.
Further, the paver further comprises an ambient temperature sensor;
the ambient temperature sensor comprises an air temperature sensor and a roadbed temperature sensor.
Further, the second set time is inversely related to the ambient temperature; the ambient temperature is a weighted average of the air temperature value detected by the air temperature sensor and the roadbed temperature detected by the roadbed temperature sensor.
Further, the state switching valve comprises a first state switching valve and a second state switching valve;
two inlets of the first state switching valve are connected to the oil return box, and two outlets of the first state switching valve are connected to a lifting cavity and a descending cavity of the two lifting cylinders respectively;
two inlets of the second state switching valve are respectively connected to the pressure oil tank and the oil return tank, and an outlet of the second state switching valve is connected to lifting cavities of the two lifting cylinders;
the paver further comprises an electric adjusting booster valve, wherein the electric adjusting booster valve is connected between the second state switching valve and the lifting cavity of the lifting oil cylinder, and the electric adjusting booster valve is used for adjusting the pressure of the lifting cavity of the lifting oil cylinder in a paving stopping state.
Further, the set time is positively correlated with the pressure of the electric regulating booster valve.
The invention also provides a paving control method, which comprises the following steps:
the state of the paver is obtained,
if the paver is switched from the paving stopping state to the normal paving state, the lifting cavity and the descending cavity of the lifting oil cylinder are controlled to be in a non-pressure state by controlling the on-off state of the state switching valve;
after the first set time, controlling the state switching valve to enable the descending cavity of the lifting oil cylinder to be in a locking state, enabling the lifting cavity to be in a non-pressure state or a locking state and controlling the paver to start paving;
after the second set time, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state.
Further, if the paver is in a paving stop state, the state switching valve is controlled so that the lifting cavity of the lifting oil cylinder is in a pressure state and the descending cavity is in a non-pressure state.
The beneficial effects of the invention are as follows:
the invention provides a paver, which changes the states of a lifting cavity and a descending cavity of a lifting oil cylinder through a state switching valve, when the paver is switched from a paving stopping state to a normal paving state, firstly, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state, after a set time is passed, a host machine returns to the normal paving state, at the moment, the descending cavity of the lifting oil cylinder is in a locking state, the lifting cavity is in the non-pressure state or the locking state, and the paver is controlled to start paving, so that the phenomenon of starting and lifting can be effectively avoided. After the second set time, the screed plate is supercooled in the material area, and the paving controller controls the state switching valve to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state, so that the screed plate enters a normal floating paving state. When the paver is in a paving stop state, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a pressure state and a non-pressure state respectively, and at the moment, shutdown indentation can be well avoided.
Drawings
FIG. 1 is a schematic view of a paver provided by the present invention;
fig. 2 is a schematic diagram of hydraulic pressure in the paver according to the present invention.
Detailed Description
The invention is further described below. The following examples are only for more clearly illustrating the technical aspects of the present invention, and are not intended to limit the scope of the present invention.
The invention provides a paver, which is shown in fig. 1 and comprises a host machine 1, a screed plate 2, a large arm 3, a lifting oil cylinder 4, a state switching valve and a paving controller 8, wherein the host machine is used for providing power and pulling the screed plate to advance, the large arm is hinged with the host machine and connected with the screed plate at the rear, the screed plate is used for primarily compacting, screeding and finally forming a pavement for paving materials, the lifting oil cylinder is hinged with the host machine and connected with the rear of the large arm so as to adjust the height of the screed plate, the state switching valve is used for changing the states of a lifting cavity and a descending cavity of the lifting oil cylinder, and the paving controller is used for controlling the state switching valve and paving functions of the paver.
In the present invention, a paving controller is particularly useful for,
when the hydraulic control system is in a paving stop state, the control state switching valve enables the lifting cavity of the lifting oil cylinder to be in a pressure state, and the descending cavity is in a non-pressure state, so that shutdown indentation can be better avoided.
When the paving state is switched from the paving stopping state to the normal paving state, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state;
after the first set time, controlling the state switching valve to enable the descending cavity of the lifting oil cylinder to be in a locking state, enabling the lifting cavity to be in a non-pressure state or a locking state and controlling the paver to start paving;
after the second set time, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state.
In the present invention, the state switching valve may be a single hydraulic valve or a combination of a plurality of hydraulic valves.
It should be noted that, in the present invention, the paving controller may be an additional controller, however, it is preferable to use the existing controller on the paving machine, so that any cost may not be increased.
It should be noted that, the lift cylinder is usually that one side of the cylinder is connected to the host, one side of the piston rod is connected to the large arm, and at this time, the lower cavity of the cylinder is a lift cavity, and the upper cavity is a descent cavity. In the present invention, this common mode is also adopted. However, the reverse arrangement is theoretically possible.
It should be noted that, one of the lifting chamber and the lowering chamber of the lifting cylinder is in a locking state, and the other is in a pressurized state, which can be equivalently regarded as a two-chamber locking state.
It should be noted that, when the paver enters the paving stop state from the normal paving state, the posture of the host machine will change to a certain extent no matter whether the paver adopts the technical scheme that the lifting cavity of the lifting cylinder is in the locking state or the technical scheme that the lifting cavity and the descending cavity of the lifting cylinder are respectively in the pressure state and the non-pressure state.
It should be noted that, the controller of the current paver generally has a timing function, so that a timer is not required to be specially set to time the paving stop state time, the first setting time and the second setting time.
In the present invention, the first set time may be a fixed value, for example, 2s or 3s, and typically, such a time interval is sufficient to allow the host pose to fully recover.
When the paver is in a paving stop state and waiting for the skip car to be longer, the asphalt mixture can become cold and harden, and when paving is restarted, the screed is easily lifted to generate a starting bench phenomenon, and at the moment, the descending cavity of the lifting oil cylinder is in a locking state, so that the screed can be prevented or lightened. And when the second set time passes, the screed plate is in a non-pressure state, namely a normal floating paving state, after the screed plate passes through the cold material area, the lifting cavity and the descending cavity of the lifting oil cylinder are in a non-pressure state again.
The faster the paving speed, the shorter the screed will take to pass through the cold-material zone, so the second set time may be inversely related, e.g., inversely related, to the paving speed.
The longer the paver is in the state of paving stop time, the more the asphalt mixture is cooled, and the longer the setting time is, so that the starting and lifting can be avoided.
The cooling degree of the asphalt mixture is related to the paving stop time, and is also related to the environment temperature, and the lower the environment temperature is, the more the asphalt mixture is cooled in the same time, and the longer the setting time is, the better the setting time is. The environment temperature can specifically comprise the temperature of the roadbed and the temperature, or the lower the temperature of the roadbed, the more the asphalt mixture is cooled in the same time, and the longer the setting time is, the better.
In one embodiment of the invention, an environmental temperature sensor 7 is arranged on the paver, and the environmental temperature sensor comprises an air temperature sensor and a roadbed temperature sensor, and is used for detecting the air temperature value and the roadbed temperature value, and the setting time II is inversely related to the environmental temperature, so that the starting and lifting phenomenon is favorably eliminated or reduced. The environment temperature value is a weighted average of the air temperature value detected by the air temperature sensor and the roadbed temperature detected by the roadbed temperature sensor. The ambient temperature sensor 7 may be mounted on a host machine, screed or other location suitable for detecting air temperature values or roadbed temperature values.
Referring to fig. 2, in one embodiment of the present invention, there are two lift cylinders and two state switching valves each. Wherein, the first state switching valve 51 is a three-position four-way electromagnetic reversing valve, and the second state switching valve 52 is a two-position three-way electromagnetic reversing valve. The two inlets of the first state switching valve 51 are connected to the T port (i.e., connected to the return tank), and the two outlets are connected to the lifting chambers and the lowering chambers of the two lifting cylinders, respectively. The two inlets of the second state switching valve 52 are connected to the P port (pressure oil) and the T port, respectively, and the outlets are connected to the lift chambers of the two lift cylinders.
In addition, the hydraulic control system further comprises an electric adjusting booster valve 6 which is connected between the second state switching valve 52 and the lifting cavity of the lifting oil cylinder, and the electric adjusting booster valve 6 is used for adjusting the pressure of the lifting cavity of the lifting oil cylinder in the paving stop state.
The paving control mode based on the structure is as follows:
in a normal paving state, the paving controller 8 controls the first state switching valve 51 and the second state switching valve 52 to be not powered, so that the lifting cavity and the descending cavity of the two lifting cylinders 4 are connected to the port T (namely connected with the oil return tank) to be in a non-pressure state, and the electric adjustment booster valve 6 is not in action at the moment.
When the paving is stopped, the paving controller 8 controls the upper position of the first state switching valve 51 and the second state switching valve 52 to be powered on, so that the descending chambers (upper chambers) of the two lifting oil cylinders 4 are connected to the T port and are in a non-pressure state, and the P port (pressure oil) is communicated with the lifting chambers (lower chambers) of the two lifting oil cylinders 4 through the second state switching valve 52 and the electric regulating booster valve 6, so that the lifting chambers are in a pressure state; in the present embodiment, the upper and lower positions of the state switching valve 51 refer to the upper and lower positions of the state switching valve 51 shown in fig. 2.
When the paver is switched from the paving stopping state to the normal paving state, the paving controller 8 controls the state switching valve I51 and the state switching valve 52 to be not powered, so that the lifting cavity and the descending cavity of the two lifting cylinders 4 are connected to the T port (namely connected with the oil return tank) and are in a non-pressure state;
after the first setting time, the paving controller 8 controls the first state switching valve 51 to be electrified in the lower position and the second state switching valve 52 to be not electrified, so that lifting cavities (lower cavities) of the two lifting oil cylinders 4 are connected to a T port and are in a non-pressure state, and descending cavities (upper cavities) of the two lifting oil cylinders 4 are in a locking (non-communicating) state;
after the second setting time, the paving controller 8 controls the state switching valve one 51 and the state switching valve 52 to be not powered, so that the lifting cavity and the descending cavity of the two lifting cylinders 4 are connected to the port T (i.e. connected to the oil return tank) and are in a non-pressure state.
It should be noted that the electric adjusting booster valve is preferably an electric proportional constant value pressure reducing valve, and the outlet pressure of the constant value pressure reducing valve, namely the pressure of a lifting cavity of the lifting oil cylinder, can be directly adjusted through current. It is also possible to achieve pressure regulation of the lift cylinder lift chamber by means of an electro proportional relief valve or other hydraulic valve.
The electrically controlled booster valve may be of a fixed pressure or of a manually controlled pressure or of an electrically controlled pressure.
The setting time may be directly related to the pressure of the electric control booster valve, for example, may be linearly related or directly proportional, for example, when the pressure of the electric control booster valve reaches the maximum value, the setting time may reach the maximum value of 3s, and when the pressure of the electric control booster valve reaches a certain proportion of the maximum value, the setting time may also reach a certain proportion of 3 s. The greater the pressure of the electrically-regulated booster valve, the greater the degree of change in the attitude of the host machine when the paver is switched from the paving-stopped state to the normal paving state, thus requiring a longer recovery time.
The paving control method based on the paver comprises the following steps:
the state of the paver is obtained,
if the paver is in a normal paving state, controlling the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state by controlling the on-off state of the state switching valve;
if the paver is in a paving stop state, controlling the lifting cavity of the lifting oil cylinder to be in a pressure state and the descending cavity to be in a non-pressure state by controlling the on-off of the state switching valve;
if the paver is switched from the paving stopping state to the normal paving state, the lifting cavity and the descending cavity of the lifting oil cylinder are controlled to be in a non-pressure state by controlling the on-off state of the state switching valve;
after the first set time, controlling the state switching valve to enable the descending cavity of the lifting oil cylinder to be in a locking state, enabling the lifting cavity to be in a non-pressure state or a locking state and controlling the paver to start paving;
after the second set time, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and variations could be made by those skilled in the art without departing from the technical principles of the present invention, and such modifications and variations should also be regarded as being within the scope of the invention.
Claims (10)
1. The paver comprises a host machine, a screed plate, a large arm and a lifting oil cylinder, and is characterized by further comprising a state switching valve and a paving controller;
the state switching valve is used for changing the state of a lifting cavity and a descending cavity of the lifting oil cylinder;
the paving controller is used for controlling the power supply of the state switching valve and controlling the paving machine to perform paving;
the paving control apparatus is particularly useful for,
when the paving state is switched from the paving stopping state to the normal paving state, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state;
after the first set time, controlling the state switching valve to enable the descending cavity of the lifting oil cylinder to be in a locking state, enable the lifting cavity to be in a non-pressure state or a locking state, and controlling the paver to start paving;
after the second set time, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state.
2. A paver according to claim 1, wherein the set time-one is a preset value.
3. A paver as claimed in claim 1, wherein the set time two is inversely related to the paving speed.
4. A paver as claimed in claim 1, wherein the set time two is positively correlated with the time at which the paver is in a paving-stopped condition.
5. A paver as claimed in claim 1, wherein the paver further comprises an ambient temperature sensor;
the ambient temperature sensor comprises an air temperature sensor and a roadbed temperature sensor.
6. A paver according to claim 5, wherein the set time two is inversely related to the ambient temperature; the ambient temperature is a weighted average of the air temperature value detected by the air temperature sensor and the roadbed temperature detected by the roadbed temperature sensor.
7. A spreading machine according to any one of claims 1-6, wherein the status switching valve comprises a first status switching valve and a second status switching valve;
two inlets of the first state switching valve are connected to the oil return box, and two outlets of the first state switching valve are connected to a lifting cavity and a descending cavity of the two lifting cylinders respectively;
two inlets of the second state switching valve are respectively connected to the pressure oil tank and the oil return tank, and an outlet of the second state switching valve is connected to lifting cavities of the two lifting cylinders;
the paver further comprises an electric adjusting booster valve, wherein the electric adjusting booster valve is connected between the second state switching valve and the lifting cavity of the lifting oil cylinder, and the electric adjusting booster valve is used for adjusting the pressure of the lifting cavity of the lifting oil cylinder in a paving stopping state.
8. A paver as claimed in claim 7, wherein the set time-is positively correlated with the pressure of the electrically-regulated booster valve.
9. A paving control method of a paving machine as claimed in any one of claims 1 to 8, including:
the state of the paver is obtained,
if the paver is switched from the paving stopping state to the normal paving state, the lifting cavity and the descending cavity of the lifting oil cylinder are controlled to be in a non-pressure state by controlling the on-off state of the state switching valve;
after the first set time, controlling the state switching valve to enable the descending cavity of the lifting oil cylinder to be in a locking state, enabling the lifting cavity to be in a non-pressure state or a locking state and controlling the paver to start paving;
after the second set time, the state switching valve is controlled to enable the lifting cavity and the descending cavity of the lifting oil cylinder to be in a non-pressure state.
10. The paving control method of a paving machine according to claim 9, wherein if the paving machine is in a paving stop state, the state switching valve is controlled such that the lifting chamber of the lifting cylinder is in a pressurized state and the lowering chamber is in a non-pressurized state.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310750528.XA CN116815586A (en) | 2023-06-25 | 2023-06-25 | Paver and paving control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310750528.XA CN116815586A (en) | 2023-06-25 | 2023-06-25 | Paver and paving control method |
Publications (1)
| Publication Number | Publication Date |
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| CN116815586A true CN116815586A (en) | 2023-09-29 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202310750528.XA Pending CN116815586A (en) | 2023-06-25 | 2023-06-25 | Paver and paving control method |
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| Country | Link |
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| CN (1) | CN116815586A (en) |
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2023
- 2023-06-25 CN CN202310750528.XA patent/CN116815586A/en active Pending
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