CN221233860U - Hydraulic steering system and engineering machinery - Google Patents
Hydraulic steering system and engineering machinery Download PDFInfo
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- CN221233860U CN221233860U CN202323642180.7U CN202323642180U CN221233860U CN 221233860 U CN221233860 U CN 221233860U CN 202323642180 U CN202323642180 U CN 202323642180U CN 221233860 U CN221233860 U CN 221233860U
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- 239000003921 oil Substances 0.000 claims abstract description 99
- 238000006073 displacement reaction Methods 0.000 claims abstract description 73
- 230000001105 regulatory effect Effects 0.000 claims abstract description 65
- 239000010720 hydraulic oil Substances 0.000 claims abstract description 20
- 238000004891 communication Methods 0.000 claims description 6
- 238000010276 construction Methods 0.000 claims description 3
- 230000009471 action Effects 0.000 description 4
- 238000001514 detection method Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000010009 beating Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000036544 posture Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000010729 system oil Substances 0.000 description 1
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Abstract
The utility model relates to the technical field of engineering machinery, in particular to a hydraulic steering system and engineering machinery. The hydraulic steering system comprises a main pump, a main control valve, a flow regulating valve, a displacement regulating oil cylinder, a steering gear and a steering oil cylinder, wherein an oil outlet of the main pump is communicated with an oil inlet of the main control valve, and an oil outlet of the main control valve is simultaneously communicated with an oil inlet of the flow regulating valve and an oil inlet of the displacement regulating valve; an oil outlet of the flow regulating valve is communicated with an oil inlet of the steering gear, and the flow regulating valve is used for regulating the flow of hydraulic oil entering the steering gear; two oil outlets of the displacement adjusting valve are respectively communicated with a rod cavity and a rodless cavity of the displacement adjusting oil cylinder, and a telescopic rod of the displacement adjusting oil cylinder is connected with the steering gear to adjust the displacement of the steering gear; the two oil outlets of the steering gear are respectively communicated with the two cavities of the steering oil cylinder. The comprehensive control of the steering speed of the steering gear is realized by the double speed regulation principle of flow and volume, and the driving safety and the operation smoothness are greatly improved.
Description
Technical Field
The utility model relates to the technical field of engineering machinery, in particular to a hydraulic steering system and engineering machinery.
Background
Currently, vehicles using hydraulically driven steering almost always use hydraulic steering to control steering angles. The existing steering hydraulic system is characterized in that oil pumped by a gear pump flows to a steering gear after being subjected to fixed diversion of a main control valve or flow control with priority of steering, and under the parameters corresponding to the number of turns of the steering gear, only a fixed turning angle can be correspondingly output, the speed of the whole vehicle and the surrounding environment cannot be intelligently identified, and rollover risks are easy to occur under the condition of too high vehicle speed. In addition, the existing steering hydraulic system has the problem that the matching between the steering device looping speed and the flow is poor, for example, under a fast-beating steering device, the flow of the gear pump controlled by the flow of the steering device through the main control valve by fixed diversion or steering priority is insufficient, the flow distributed to the steering oil cylinder by the steering device cannot be met, the problem of heavy steering wheel occurs, the operation force of a driver is greatly increased, and the vibration resistance is felt.
Disclosure of utility model
The utility model aims to provide a steering hydraulic system and engineering machinery, which realize comprehensive control of steering speed of a steering gear and improve driving safety and operation smoothness.
To achieve the purpose, the utility model adopts the following technical scheme:
The hydraulic steering system comprises an oil tank, a main pump, a main control valve, a flow regulating valve, a displacement regulating oil cylinder, a steering gear and a steering oil cylinder, wherein an oil inlet of the main pump is communicated with the oil tank, an oil outlet of the main pump is communicated with an oil inlet of the main control valve, and an oil outlet of the main control valve is simultaneously communicated with an oil inlet of the flow regulating valve and an oil inlet of the displacement regulating valve; the oil outlet of the flow regulating valve is communicated with the oil inlet of the steering gear, and the flow regulating valve is used for regulating the flow of hydraulic oil entering the steering gear; two oil outlets of the displacement adjusting valve are respectively communicated with a rod cavity and a rodless cavity of the displacement adjusting oil cylinder, and a telescopic rod of the displacement adjusting oil cylinder is connected with the steering gear to adjust the displacement of the steering gear; and two oil outlets of the steering gear are respectively communicated with two cavities of the steering oil cylinder.
As a preferable technical scheme of the hydraulic steering system, the flow regulating valve is a proportional valve, and the flow of hydraulic oil entering the steering gear can be regulated by regulating the opening amount of the flow regulating valve.
As the preferable technical scheme of the hydraulic steering system, the displacement regulating valve is a proportional reversing valve, the displacement regulating valve is provided with two working positions, when the displacement regulating valve is in a first working position, the telescopic rod of the displacement regulating cylinder stretches out, when the displacement regulating valve is in a second working position, the telescopic rod of the displacement regulating cylinder retracts, and the flow of hydraulic oil entering the displacement regulating cylinder can be regulated by regulating the opening amount of the displacement regulating valve.
As the preferable technical scheme of the hydraulic steering system, the displacement regulating valve is a two-position four-way valve.
As the preferable technical scheme of the hydraulic steering system, an oil suction filter is arranged on a communicating pipeline between an oil inlet of the main pump and the oil tank.
As the preferable technical scheme of the hydraulic steering system, an oil return port of the steering gear is communicated with the oil tank, and an oil return filter is arranged on a communicating pipeline between the oil return port of the steering gear and the oil tank.
As the preferable technical scheme of the hydraulic steering system, the hydraulic steering system further comprises a controller, and the flow regulating valve and the displacement regulating valve are both in communication connection with the controller.
As the preferable technical scheme of the hydraulic steering system, the hydraulic steering system further comprises a vehicle speed sensor, a road condition sensor and a goods position sensor, wherein the vehicle speed sensor, the road condition sensor and the goods position sensor are all in communication connection with the controller.
A construction machine comprising a hydraulic steering system according to any one of the above aspects.
As a preferable technical scheme of the engineering machinery, the engineering machinery is a forklift.
The utility model has the beneficial effects that:
According to the hydraulic steering system provided by the utility model, the hydraulic oil pumped by the main pump enters the steering gear after passing through the main control valve and the flow regulating valve, the flow rate of the hydraulic oil entering the steering gear can be regulated through the flow regulating valve, the matching property between the looping speed and the flow rate of the steering gear is improved, and when an operator performs a quick turning action through misoperation, the flow rate of the hydraulic oil entering the steering gear can be increased through regulating the flow regulating valve, so that the operability and the operation comfort of the whole steering gear are improved. Meanwhile, hydraulic oil pumped by the main pump enters the displacement adjusting oil cylinder through the main control valve and the displacement adjusting valve so as to adjust the expansion of the telescopic rod of the displacement adjusting oil cylinder, thereby adjusting the displacement of the steering gear, and when an operator performs quick turning action through misoperation, the displacement of the steering gear can be reduced through adjusting the displacement adjusting valve, and the occurrence of the risks of side turning of a vehicle and falling of goods is avoided. The comprehensive control of the steering speed of the steering gear is realized by the double speed regulation principle of flow and volume, so that the steering gear is better adapted to the speed and the surrounding environment of the whole car, and the driving safety and the operation smoothness are greatly improved.
Drawings
Fig. 1 is a schematic diagram of a hydraulic steering system according to an embodiment of the present utility model.
In the figure:
1. An oil tank; 2. a main pump; 3. a main control valve; 4. a flow regulating valve; 5. a displacement regulating valve; 6. a displacement adjusting cylinder; 7. a diverter; 8. a steering cylinder; 9. a controller; 10. a vehicle speed sensor; 11. road condition sensors; 12. a cargo position sensor; 13. an oil absorption filter; 14. and (5) an oil return filter.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present utility model and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be configured and operated in a specific direction, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance. In the description of the present utility model, unless otherwise indicated, the meaning of "a plurality" is two or more.
In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed", "connected" and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected or integrally connected; either mechanically or electrically. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.
In the present utility model, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.
Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the utility model.
As shown in fig. 1, the embodiment of the utility model provides a hydraulic steering system, which comprises an oil tank 1, a main pump 2, a main control valve 3, a flow control valve 4, a displacement control valve 5, a displacement control oil cylinder 6, a steering device 7 and a steering oil cylinder 8, wherein an oil inlet of the main pump 2 is communicated with the oil tank 1, an oil outlet of the main pump 2 is communicated with an oil inlet of the main control valve 3, an oil outlet of the main control valve 3 is simultaneously communicated with an oil inlet of the flow control valve 4 and an oil inlet of the displacement control valve 5, and the main control valve 3 is used for realizing steering priority or fixed diversion, which is the prior art and is not described in detail herein. The oil outlet of the flow regulating valve 4 is communicated with the oil inlet of the steering gear 7, and the flow regulating valve 4 is used for regulating the flow of hydraulic oil entering the steering gear 7; two oil outlets of the displacement adjusting valve 5 are respectively communicated with a rod cavity and a rodless cavity of the displacement adjusting oil cylinder 6, and a telescopic rod of the displacement adjusting oil cylinder 6 is connected with the steering gear 7 to adjust the displacement of the steering gear 7; the two oil outlets of the steering gear 7 are respectively communicated with the two cavities of the steering cylinder 8.
The hydraulic oil pumped by the main pump 2 enters the steering gear 7 after passing through the main control valve 3 and the flow regulating valve 4, the flow of the hydraulic oil entering the steering gear 7 can be regulated through the flow regulating valve 4, the matching performance between the looping speed and the flow of the steering gear 7 is improved, and when an operator performs quick turning action through misoperation, the flow of the hydraulic oil entering the steering gear 7 can be increased through regulating the flow regulating valve 4, so that the operability and the operation comfort of the whole vehicle are improved. Meanwhile, hydraulic oil pumped by the main pump 2 enters the displacement adjusting oil cylinder 6 through the main control valve 3 and the displacement adjusting valve 5 to adjust the expansion of a telescopic rod of the displacement adjusting oil cylinder 6, so that the displacement of the steering gear 7 is adjusted, when an operator performs quick turning action through misoperation, the displacement of the steering gear 7 can be reduced through adjusting the displacement adjusting valve 5, and the occurrence of risks of rollover of a vehicle and falling of goods is avoided. The comprehensive control of the steering speed of the steering gear 7 is realized by the double speed regulation principle of flow and volume, so that the steering gear is better adapted to the speed and the surrounding environment of the whole vehicle, and the driving safety and the operation smoothness are greatly improved.
In the present embodiment, the flow rate adjustment valve 4 is a proportional valve, and the flow rate of the hydraulic oil that enters the steering gear 7 can be adjusted by adjusting the opening amount of the flow rate adjustment valve 4. The flow regulating valve 4 is illustratively a two-position three-way valve, the flow regulating valve 4 has two working positions, when the flow regulating valve 4 is in the first working position, hydraulic oil only flows to the oil inlet of the steering gear 7 through the first working position of the flow regulating valve 4, when the flow regulating valve 4 is in the second working position, one path of hydraulic oil flows to the oil inlet of the steering gear 7 through the second working position of the flow regulating valve 4, and the other path flows back to the oil tank 1 through the second working position of the flow regulating valve 4. Of course, the foregoing is illustrative only and not limiting.
In this embodiment, the displacement adjusting valve 5 is a proportional reversing valve, the displacement adjusting valve 5 has two working positions, when the displacement adjusting valve 5 is in the first working position, the telescopic rod of the displacement adjusting cylinder 6 extends out, when the displacement adjusting valve 5 is in the second working position, the telescopic rod of the displacement adjusting cylinder 6 retracts, and the flow rate of hydraulic oil entering the displacement adjusting cylinder 6 can be adjusted by adjusting the opening amount of the displacement adjusting valve 5. The displacement adjusting valve 5 is a two-position four-way valve, but not limited thereto.
An oil suction filter 13 is arranged on a communicating pipeline between the oil inlet of the main pump 2 and the oil tank 1. The oil return port of the steering gear 7 is communicated with the oil tank 1, and an oil return filter 14 is arranged on a communicating pipeline between the oil return port of the steering gear 7 and the oil tank 1. The oil suction filter 13 and the oil return filter 14 are arranged to filter the system oil, so that the influence of impurities on the components in the system can be avoided, and the service life of the components in the system can be prolonged.
The hydraulic steering system provided by the utility model further comprises a controller 9, and the flow regulating valve 4 and the displacement regulating valve 5 are all in communication connection with the controller 9. The controller 9 controls the operation position and the opening of the flow rate adjusting valve 4 and the operation position and the opening of the displacement adjusting valve 5 according to the traveling speed, the traveling road condition, the cargo position, and the like. Further, the hydraulic steering system further comprises a vehicle speed sensor 10, a road condition sensor 11 and a cargo position sensor 12, wherein the vehicle speed sensor 10, the road condition sensor 11 and the cargo position sensor 12 are all in communication connection with the controller 9, and the controller 9 controls the flow regulating valve 4 and the displacement regulating valve 5 according to signals of the vehicle speed sensor 10, the road condition sensor 11 and the cargo position sensor 12, so that intelligent control of steering speed is realized.
In this embodiment, the controller 9 stores allowable vehicle speeds and turning speeds of different cargo weights under different vehicle postures, and the vehicle speed sensor 10, the road condition sensor 11 and the cargo position sensor 12 transmit detection results to the controller 9, and the controller 9 combines detection parameters of the vehicle speed sensor 10, the road condition sensor 11 and the cargo position sensor 12 to control the maximum rotation speed of the whole vehicle engine or the motor, the flow regulating valve 4 and the displacement regulating valve 5, thereby realizing limitation of the running speed and the turning speed of the whole vehicle and improving the running safety and the operation smoothness.
In this embodiment, the road condition sensor 11 is a non-contact road condition detector, which adopts a remote sensing technology, and a multispectral measurement technology can accurately detect the existence state and thickness of ice, snow and water on the road surface, and can also detect weather phenomena such as fog, rain and snow affecting traffic safety in real time. The specific functions are as follows: a. detecting the accumulated water, snow and icing state of the road surface; b. remote sensing to detect road surface and bridge surface condition; c. the non-embedded type installation is quick and simple; d. traffic flow and accident-prone areas. The road condition sensor 11 is a prior art and will not be described in detail herein.
The embodiment of the utility model also provides engineering machinery comprising the hydraulic steering system. By adopting the hydraulic steering system, the comprehensive control of the steering speed of the steering gear 7 is realized, so that the hydraulic steering system is better adapted to the speed of the whole vehicle and the surrounding environment, and the driving safety and the operation smoothness are greatly improved. In the present embodiment, the construction machine is a forklift, but is not limited thereto.
It is to be understood that the above examples of the present utility model are provided for clarity of illustration only and are not limiting of the embodiments of the present utility model. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the utility model are desired to be protected by the following claims.
Claims (10)
1. A hydraulic steering system, comprising:
The hydraulic control system comprises an oil tank (1), a main pump (2), a main control valve (3), a flow control valve (4), a displacement control valve (5), a displacement control oil cylinder (6), a steering gear (7) and a steering oil cylinder (8), wherein an oil inlet of the main pump (2) is communicated with the oil tank (1), an oil outlet of the main pump (2) is communicated with an oil inlet of the main control valve (3), and an oil outlet of the main control valve (3) is simultaneously communicated with an oil inlet of the flow control valve (4) and an oil inlet of the displacement control valve (5); an oil outlet of the flow regulating valve (4) is communicated with an oil inlet of the steering gear (7), and the flow regulating valve (4) is used for regulating the flow of hydraulic oil entering the steering gear (7); two oil outlets of the displacement adjusting valve (5) are respectively communicated with a rod cavity and a rodless cavity of the displacement adjusting oil cylinder (6), and a telescopic rod of the displacement adjusting oil cylinder (6) is connected with the steering gear (7) to adjust the displacement of the steering gear (7); two oil outlets of the steering gear (7) are respectively communicated with two cavities of the steering oil cylinder (8).
2. The hydraulic steering system according to claim 1, characterized in that the flow rate adjustment valve (4) is a proportional valve, and the flow rate of the hydraulic oil entering the steering gear (7) can be adjusted by adjusting the opening amount of the flow rate adjustment valve (4).
3. The hydraulic steering system according to claim 1, wherein the displacement adjustment valve (5) is a proportional directional valve, the displacement adjustment valve (5) has two working positions, when the displacement adjustment valve (5) is in a first working position, a telescopic rod of the displacement adjustment cylinder (6) is extended, when the displacement adjustment valve (5) is in a second working position, the telescopic rod of the displacement adjustment cylinder (6) is retracted, and the flow rate of hydraulic oil entering the displacement adjustment cylinder (6) can be adjusted by adjusting the opening amount of the displacement adjustment valve (5).
4. A hydraulic steering system according to claim 3, characterized in that the displacement regulating valve (5) is a two-position four-way valve.
5. Hydraulic steering system according to claim 1, characterized in that an oil suction filter (13) is arranged on the communication line between the oil inlet of the main pump (2) and the oil tank (1).
6. The hydraulic steering system according to claim 1, characterized in that the return port of the steering gear (7) communicates with the oil tank (1), and that an return filter (14) is provided on the communication line between the return port of the steering gear (7) and the oil tank (1).
7. The hydraulic steering system according to claim 1, further comprising a controller (9), wherein the flow regulating valve (4) and the displacement regulating valve (5) are both communicatively connected to the controller (9).
8. The hydraulic steering system according to claim 7, further comprising a vehicle speed sensor (10), a road condition sensor (11) and a cargo position sensor (12), wherein the vehicle speed sensor (10), the road condition sensor (11) and the cargo position sensor (12) are all communicatively connected to the controller (9).
9. A construction machine comprising a hydraulic steering system according to any one of claims 1-8.
10. The work machine of claim 9, wherein the work machine is a forklift.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202323642180.7U CN221233860U (en) | 2023-12-29 | 2023-12-29 | Hydraulic steering system and engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202323642180.7U CN221233860U (en) | 2023-12-29 | 2023-12-29 | Hydraulic steering system and engineering machinery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN221233860U true CN221233860U (en) | 2024-06-28 |
Family
ID=91599621
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202323642180.7U Active CN221233860U (en) | 2023-12-29 | 2023-12-29 | Hydraulic steering system and engineering machinery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN221233860U (en) |
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2023
- 2023-12-29 CN CN202323642180.7U patent/CN221233860U/en active Active
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