CN217804897U - Steering system of road roller - Google Patents
Steering system of road roller Download PDFInfo
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- CN217804897U CN217804897U CN202221961218.XU CN202221961218U CN217804897U CN 217804897 U CN217804897 U CN 217804897U CN 202221961218 U CN202221961218 U CN 202221961218U CN 217804897 U CN217804897 U CN 217804897U
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Abstract
The utility model discloses a road roller steering system, which comprises a hydraulic steering system and a steering gear, wherein the hydraulic steering system and the steering gear are arranged between a front frame and a rear frame which are hinged with each other, and the steering gear controls the relative swing angle of the front frame and the rear frame through the hydraulic steering system; the hydraulic steering system comprises a steering oil cylinder and an electric control steering proportional valve, and the electric control steering proportional valve controls the stretching of the steering oil cylinder; the steering oil cylinder is provided with a piston rod stretching quantity sensor, the steering gear is provided with a steering angle sensor, a controller is arranged between the hydraulic steering system and the steering gear, and the controller controls the opening of the electric control steering proportional valve according to signals of the steering angle sensor and the piston rod stretching quantity sensor. Has the beneficial effects that: the utility model discloses a steering angle and the steering wheel turned angle of control complete machine keep in step, have improved steering system response speed, have improved the obstacle avoidance ability of complete machine, can reduce operator's manipulation strength simultaneously. The reliability of the steering system is improved by arranging the emergency steering system.
Description
Technical Field
The utility model relates to a part of road roller, in particular to road roller a steering system belongs to engineering machine tool technical field.
Background
The road roller is also called soil compactor, which is a kind of road repairing equipment. The road roller belongs to the field of road equipment in engineering machinery, is widely used for the filling compaction operation of large engineering projects such as high-grade highways, railways, airport runways, dams, stadiums and the like, and can roll sandy, semi-viscous and viscous soil, roadbed stabilized soil and asphalt concrete pavement layers. The roller is suitable for various compaction operations under the action of the gravity of the machine, so that the compacted layer is permanently deformed and compacted.
The existing steering system of the road roller is a traditional hinged steering system, a steering gear is driven by rotating a steering wheel, the stretching of a steering oil cylinder is controlled, a front frame and a rear frame are pushed to form a steering angle, the steering angle of the whole vehicle and the number of turns of the steering wheel do not have a fixed relation, the steering angle and the number of turns of the steering wheel do not depend on the experience of an operator, and the steering system can be a great challenge for a novice. In addition, the weight of the road roller is generally larger, some machines can reach 40 tons, steel wheels of most machines are driven wheels, the braking distance is longer, when an emergency situation occurs, besides emergency braking, the rapid response of a steering system is also a very important obstacle avoidance means, a traditional steering wheel needs to rotate 3-4 circles to adjust the steering angle to the maximum angle, the response speed of the steering system is slower, and the obstacle avoidance capability of the whole machine is influenced. For a single steel wheel road roller constructed on a roadbed, due to the reasons of larger weight, uneven working surface, low working speed and the like, the traditional steering mode operation force is much larger than that of a common machine, the labor intensity of a driver is increased when the road roller is operated for a long time, and the fatigue of personnel is caused.
Disclosure of Invention
The invention aims to: the utility model aims at providing a road roller a steering system to the problem that exists among the prior art, the utility model discloses a steering angle and the steering wheel turned angle of control complete machine keep synchronous, have improved a steering system response speed, have improved the obstacle avoidance ability of complete machine, can reduce operator's manipulation strength simultaneously.
The technical scheme is as follows: a steering system of a road roller comprises a hydraulic steering system and a steering gear, wherein the hydraulic steering system and the steering gear are arranged between a front frame and a rear frame which are hinged with each other; the hydraulic steering system comprises a steering oil cylinder and an electric control steering proportional valve, and the electric control steering proportional valve controls the steering oil cylinder to stretch; the steering oil cylinder is provided with a piston rod stretching quantity sensor, the steering gear is provided with a steering angle sensor, a controller is arranged between the hydraulic steering system and the steering gear, and the controller controls the opening of the electric control steering proportional valve according to signals of the steering angle sensor and the piston rod stretching quantity sensor.
The utility model discloses a turn to angle sensor and monitor the steering angle of steering gear, turn to the turn signal that angle sensor recorded and turn to the instruction as input signal to controller departure, the controller converts into the flexible volume of steering cylinder piston rod according to the calculation procedure that presets, the controller is according to conversion result to automatically controlled steering proportional valve control signal, automatically controlled steering proportional valve realizes turning to for the steering cylinder fuel feeding, the flexible volume of the piston rod of the flexible volume sensor monitoring steering cylinder of piston rod, the flexible volume that the flexible volume sensor of piston rod does not receive feeds back to the controller as the result, the control is according to the automatically controlled break-make that turns to the proportional valve of the flexible volume sensor feedback condition control of piston rod, make the steering angle and the steering gear turned angle of complete machine keep in step.
The utility model discloses not only make steering system's response speed obtain improving to because steering system response speed is fast, improved the sensitivity of complete machine when emergency, avoid taking place comparatively serious accident, simultaneously because complete machine steering angle and steering wheel turned angle keep synchronous, also reduced operator's the operation degree of difficulty.
Preferably, in order to prevent serious accidents caused by the failure of the steering system and further improve the reliability of the steering system, the hydraulic steering system comprises a mechanical steering valve and an emergency steering electromagnetic valve which are connected with the electric control steering proportional valve in parallel, the mechanical steering valve is mechanically connected with a steering gear, the emergency steering electromagnetic valve is a two-position three-way electromagnetic valve and is in control connection with a controller, and a main oil supply path of the hydraulic steering system is respectively communicated with the electric control steering proportional valve and the mechanical steering valve through the emergency steering electromagnetic valve. When a steering system breaks down, the emergency steering electromagnetic valve is powered off, the mechanical steering valve is connected to the main oil supply way, an operator directly controls the mechanical steering valve through the steering gear to complete emergency steering, and shutdown troubleshooting is carried out in time, so that accidents caused by the fact that the steering system breaks down are avoided, risks of accidents when the whole machine breaks down are reduced, and meanwhile, safety of the operator and the public is guaranteed.
Preferably, in order to supply power to the steering angle sensor and the piston rod stretching amount sensor, the controller comprises a sensor power supply input port and a sensor grounding port; the controller respectively supplies power to the steering angle sensor and the piston rod telescopic quantity sensor through the sensor power supply input port and the sensor ground port.
Preferably, in order to control the steering oil cylinder through the electric control steering proportional valve so as to control the left turn or the right turn of the whole machine, the controller comprises a left turn signal port and a right turn signal port; and the controller respectively sends control signals to the electric control steering proportional valve through the left-turning signal port and the right-turning signal port.
Preferably, in order to accurately obtain the steering angle of the steering gear in real time, the controller comprises a steering gear steering angle signal port; and the controller receives a steering angle signal of the steering gear measured by the steering angle sensor through a steering angle signal port of the steering gear.
Preferably, in order to accurately acquire the state of the steering oil cylinder in real time, the controller comprises an oil cylinder state signal port; and the controller receives an oil cylinder state signal measured by the piston rod stretching amount sensor through an oil cylinder state signal port.
Preferably, in order to realize the switching of the working state of the emergency steering electromagnetic valve, the controller comprises an emergency turning switching signal port; and the controller sends a switching signal to the emergency steering electromagnetic valve through the emergency turning switching signal port.
Preferably, in order to reduce the speed of the whole machine in time when the steering system breaks down, the controller comprises a deceleration signal port, the whole road roller is provided with a whole vehicle speed controller, and the controller sends a deceleration signal to the whole vehicle speed controller through the deceleration signal port.
A control method for a steering system of a road roller, comprising the steps of:
the method comprises the following steps that firstly, a system is started, after the whole machine is started, a controller carries out system self-check, the step II is carried out when the system works normally, and the step III is carried out when the system has faults;
step two, the electric control steering system works, the controller energizes the emergency steering electromagnetic valve, and the electric control steering proportional valve is connected to a main oil supply path of the hydraulic steering system through the emergency steering electromagnetic valve; the controller converts the rotating angle of the steering gear measured by the steering angle sensor into the telescopic length of the piston rod of the steering oil cylinder according to the relation between the rotating angle of the steering gear and the hinged point position, the controller controls the telescopic length of the piston rod of the steering oil cylinder by controlling the current of the electric control steering proportional valve, the piston rod telescopic amount sensor monitors the telescopic amount of the piston rod of the steering oil cylinder, and when the telescopic amount of the piston rod of the steering oil cylinder reaches a set value, the electric control steering proportional valve is powered off, and steering is completed;
step three, the emergency steering system works, when the steering system breaks down, the controller sends a deceleration signal to the speed controller of the whole vehicle through a deceleration signal port, the emergency steering electromagnetic valve is powered off, the mechanical steering valve is connected to a main oil supply way of the hydraulic steering system through the emergency steering electromagnetic valve, the steering gear directly controls the mechanical steering valve to complete emergency steering through a mechanical connection mode, and the whole vehicle stops for fault maintenance; returning to the first step after the fault is eliminated;
step four, stopping the machine for self-checking, finish the homework before stopping the body system to carry on the self-checking, when there are faults of the steering system, the system alarms and reminds and overhauls; when there is no fault, the system shuts down automatically.
Has the advantages that: the utility model discloses a steering gear angle signal that the controller detected out according to turning to angle sensor controls the aperture of automatically controlled proportion valve that turns to, and give the signal that automatically controlled proportion valve sent through turning to signal port on a left side and turning to right side signal port, thereby control the flexible length of steering cylinder piston rod that turns to on a left side or turning to the right side, make preceding frame and back frame form the angle of relative swing, then the controller controls the aperture of automatically controlled proportion valve through the steering cylinder status signal that the piston rod flexible volume sensor that the cylinder status signal port received records, further make the steering angle and the steering wheel turned angle of complete machine keep in step, and emergency steering solenoid valve and mechanical steering valve have still been set up, when the steering gear trouble, the deceleration signal port sends the deceleration signal for speed controller, send switching signal for emergency steering solenoid valve through the switching signal port of emergency turning to, carry out emergency steering by the direct mechanical control mechanical steering valve of steering gear, thereby handle the emergency when the steering gear trouble, personnel safety has been ensured, steering gear response speed has been improved, the obstacle avoidance ability of complete machine has been improved, can reduce operator's manipulation strength simultaneously.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a structural view of a steering system of the road roller of the present invention;
FIG. 2 is a structural diagram of the hydraulic steering system of the present invention;
FIG. 3 is a circuit diagram of a controller according to the present invention;
fig. 4 is a flowchart of the control method of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.
In the present application, unless expressly stated or limited otherwise, the recitation of a first feature "on" or "under" a second feature may include the recitation of the first and second features being in direct contact, and may also include the recitation of the first and second features not being in direct contact, but being in contact with another feature between them. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
As shown in fig. 1, a steering system of a road roller comprises a hydraulic steering system 3 and a steering gear 4 which are arranged between a front frame 1 and a rear frame 2 which are hinged with each other, wherein the steering gear 4 controls the relative swing angle of the front frame 1 and the rear frame 2 through the hydraulic steering system 3; the hydraulic steering system 3 comprises a steering oil cylinder 31 and an electric control steering proportional valve 32, and the electric control steering proportional valve 32 controls the telescopic motion of the steering oil cylinder 31; the steering oil cylinder 31 is provided with a piston rod stretching amount sensor 33, the steering machine 4 is provided with a steering angle sensor 41, a controller 5 is arranged between the hydraulic steering system 3 and the steering machine 4, and the controller 5 controls the opening of the electric control steering proportional valve 32 according to signals of the steering angle sensor 41 and the piston rod stretching amount sensor 33.
When an operator starts the system, the steering gear 4 is rotated, the steering angle sensor 41 sends a steering angle signal of the steering gear 4 to a steering gear steering angle signal port of the controller 5, the controller 5 sends the steering angle signal to the electric control steering proportional valve 32 through a left steering signal port or a right steering signal port, so that the expansion and contraction of the piston rod of the steering oil cylinder 31 are controlled, the movement direction of the whole machine is controlled, and after the expansion and contraction amount of the piston rod reaches a set value, the controller 5 receives the state of the steering oil cylinder 31 measured by the piston rod expansion and contraction amount sensor 33 through an oil cylinder state signal port to control the electric control steering proportional valve 32 to be powered off, so that the steering of the whole machine is completed. The utility model discloses not only realize that the complete machine turns to the angle and 4 steering angles of steering gear keep synchronous, still make the response speed of a steering system obtain improving, reduced operator's the operation degree of difficulty to owing to have high response speed's a steering system, so also improved the sensitivity of complete machine when emergency, avoid taking place comparatively serious accident.
As shown in fig. 2, in order to prevent a serious accident caused by a failure of the steering system and further improve the steering reliability, the hydraulic steering system 3 includes a mechanical steering valve 34 and an emergency steering solenoid valve 35 which are connected in parallel with the electric control steering proportional valve 32, the mechanical steering valve 34 is mechanically connected with the steering engine 4, the emergency steering solenoid valve 35 is a two-position three-way solenoid valve and is in control connection with the controller 5, and a main oil supply path of the hydraulic steering system 3 is respectively communicated with the electric control steering proportional valve 32 and the mechanical steering valve 34 through the emergency steering solenoid valve 35.
When the steering system breaks down, the controller 5 sends a deceleration signal to the speed controller 5 of the whole machine through a deceleration signal port, the emergency steering electromagnetic valve 35 is powered off, the steering system is switched to a mechanical mode, the mechanical steering valve 34 is connected to a main oil supply way, an operator directly controls the mechanical steering valve 34 through the steering gear 4 to complete emergency steering, and the emergency steering is stopped for timely fault maintenance, so that accidents caused by the fact that the steering system breaks down are avoided, the risk of accidents when the whole machine breaks down is reduced, and meanwhile, the safety of the operator and the public is guaranteed.
As shown in fig. 3, in order to supply power to the steering angle sensor 41 and the piston rod expansion amount sensor 33, the controller 5 includes a sensor power input port, a sensor ground port; the controller 5 supplies power to the steering angle sensor 41 and the piston rod expansion sensor 33 through a sensor power input port and a sensor ground port, respectively.
In order to control the steering oil cylinder 31 through the electric control steering proportional valve 32 so as to control the left turn or the right turn of the whole machine, the controller 5 comprises a left turn signal port and a right turn signal port; the controller 5 sends control signals to the electrically controlled steering proportional valve 32 through the left-turn signal port and the right-turn signal port, respectively.
In order to accurately obtain the steering angle of the steering gear 4 in real time, the controller 5 comprises a steering gear steering angle signal port; the controller 5 receives a steering angle signal of the steering gear 4 measured by the steering angle sensor 41 through a steering angle signal port of the steering gear.
In order to accurately obtain the state of the steering cylinder 31 in real time, the controller 5 comprises a cylinder state signal port; the controller 5 receives a steering cylinder 31 state signal measured by a piston rod expansion and contraction amount sensor 33 through a cylinder state signal port.
In order to realize the switching of the working state of the emergency steering electromagnetic valve 35, the controller 5 comprises an emergency turning switching signal port; and the controller 5 sends a switching signal to the emergency steering electromagnetic valve 35 through an emergency turning switching signal port.
In order to reduce the speed of the whole vehicle in time when the steering system breaks down, the controller 5 comprises a speed reduction signal port, the whole vehicle speed controller is arranged on the road roller, and the controller 5 sends a speed reduction signal to the whole vehicle speed controller through the speed reduction signal port.
As shown in fig. 4, a method for controlling a steering system of a road roller comprises the following steps:
step one, starting a system, after the whole machine is started, carrying out system self-checking by a controller 5, entering a step two when the system works normally, and entering a step three when the system has a fault;
step two, the electric control steering system works, the controller 5 energizes the emergency steering electromagnetic valve 35, and the electric control steering proportional valve 32 is connected to a main oil supply way of the hydraulic steering system 3 through the emergency steering electromagnetic valve 35; the controller 5 converts the rotating angle of the steering gear 4 measured by the steering angle sensor 41 and the relation of the hinged point position into the telescopic length of the piston rod of the steering oil cylinder 31, the controller 5 controls the telescopic length of the piston rod of the steering oil cylinder 31 by controlling the current of the electric control steering proportional valve 32, the piston rod telescopic amount sensor 33 monitors the telescopic amount of the piston rod of the steering oil cylinder 31, and when the telescopic amount of the piston rod of the steering oil cylinder 31 reaches a set value, the electric control steering proportional valve 32 is powered off, and the steering is completed;
step three, the emergency steering system works, when the steering system breaks down, the controller 5 sends a deceleration signal to the speed controller of the whole vehicle through a deceleration signal port, meanwhile, the emergency steering electromagnetic valve 35 is powered off, the mechanical steering valve 34 is connected to a main oil supply way of the hydraulic steering system 3 through the emergency steering electromagnetic valve 35, the steering gear 4 directly controls the mechanical steering valve 34 to complete emergency steering through a mechanical connection mode, and the whole vehicle stops for fault maintenance; returning to the step one after the fault is eliminated;
step four, stopping the self-checking, finish the operation before stopping the body system to carry on the self-checking, when there is a steering system trouble, the system alarms and reminds and overhauls; when there is no fault, the system shuts down automatically.
In the present specification, the embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (8)
1. A steering system of a road roller comprises a hydraulic steering system (3) and a steering gear (4) which are arranged between a front frame (1) and a rear frame (2) which are hinged with each other, wherein the steering gear (4) controls the relative swing angle of the front frame (1) and the rear frame (2) through the hydraulic steering system (3); the method is characterized in that: the hydraulic steering system (3) comprises a steering oil cylinder (31) and an electric control steering proportional valve (32), and the electric control steering proportional valve (32) controls the steering oil cylinder (31) to stretch and retract; the steering system is characterized in that a piston rod stretching quantity sensor (33) is arranged on the steering oil cylinder (31), a steering angle sensor (41) is arranged on the steering machine (4), a controller (5) is arranged between the hydraulic steering system (3) and the steering machine (4), and the controller (5) controls the opening degree of the electric control steering proportional valve (32) according to signals of the steering angle sensor (41) and the piston rod stretching quantity sensor (33).
2. The road roller steering system of claim 1, wherein: the hydraulic steering system (3) comprises a mechanical steering valve (34) and an emergency steering electromagnetic valve (35) which are connected with the electric control steering proportional valve (32) in parallel, the mechanical steering valve (34) is mechanically connected with the steering gear (4), the emergency steering electromagnetic valve (35) is a two-position three-way electromagnetic valve and is in control connection with the controller (5), and a main oil supply channel of the hydraulic steering system (3) is respectively communicated with the electric control steering proportional valve (32) and the mechanical steering valve (34) through the emergency steering electromagnetic valve (35).
3. The road roller steering system of claim 2, wherein: the controller (5) comprises a sensor power supply input port and a sensor grounding port; the controller (5) respectively supplies power to the steering angle sensor (41) and the piston rod stretching amount sensor (33) through a sensor power supply input port and a sensor grounding port.
4. A road roller steering system according to claim 3, wherein: the controller (5) comprises a left-turn signal port and a right-turn signal port; and the controller (5) respectively sends control signals to the electric control steering proportional valve (32) through the left-turn signal port and the right-turn signal port.
5. The road roller steering system of claim 4, wherein: the controller (5) comprises a steering angle signal port of a steering gear; the controller (5) receives a steering angle signal of the steering gear measured by the steering angle sensor (41) through a steering angle signal port of the steering gear.
6. The road roller steering system of claim 5, wherein: the controller (5) comprises an oil cylinder state signal port; and the controller (5) receives an oil cylinder state signal measured by the piston rod stretching amount sensor (33) through an oil cylinder state signal port.
7. The road roller steering system of claim 6, wherein: the controller (5) comprises an emergency turn-around switching signal port; and the controller (5) sends a switching signal to the emergency steering electromagnetic valve (35) through an emergency turning switching signal port.
8. The road roller steering system of claim 7, wherein: the controller (5) comprises a deceleration signal port, the whole road roller is provided with a whole vehicle speed controller, and the controller (5) sends a deceleration signal to the whole vehicle speed controller through the deceleration signal port.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221961218.XU CN217804897U (en) | 2022-07-26 | 2022-07-26 | Steering system of road roller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221961218.XU CN217804897U (en) | 2022-07-26 | 2022-07-26 | Steering system of road roller |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217804897U true CN217804897U (en) | 2022-11-15 |
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ID=83971207
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202221961218.XU Active CN217804897U (en) | 2022-07-26 | 2022-07-26 | Steering system of road roller |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217804897U (en) |
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2022
- 2022-07-26 CN CN202221961218.XU patent/CN217804897U/en active Active
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