CN109253118A - A kind of automatic switchover constant pressure oil source device based on pressure judgement - Google Patents
A kind of automatic switchover constant pressure oil source device based on pressure judgement Download PDFInfo
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- CN109253118A CN109253118A CN201811270768.5A CN201811270768A CN109253118A CN 109253118 A CN109253118 A CN 109253118A CN 201811270768 A CN201811270768 A CN 201811270768A CN 109253118 A CN109253118 A CN 109253118A
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- pressure
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- oil
- oil source
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- 238000006073 displacement reaction Methods 0.000 abstract description 5
- 239000002828 fuel tank Substances 0.000 abstract 3
- 238000010586 diagram Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a kind of automatic switchover constant pressure oil source devices based on pressure judgement, comprising: fuel tank, constant pressure variable displacement pump, emergency pump, the first high pressure filter, the second high pressure filter, return filter and Oil-source control unit；Wherein, the fuel tank respectively with the constant pressure variable displacement pump, the emergency pump, the return filter piping connection；The constant pressure variable displacement pump and the first high pressure filter piping connection, first high pressure filter and the Oil-source control unit piping connection；The Oil-source control unit respectively with the return filter, the second high pressure filter piping connection；Second high pressure filter and the emergency pump piping connection.The present invention, which solves traditional oil sources scheme, to automatically adjust output flow according to system requirements, when system requirements are lower, most of flow of hydraulic pump output all passes through overflow valve and returns to fuel tank, there is a problem of that calorific value is big, energy utilization rate is low and system reliability is low.
Description
Technical Field
The invention belongs to the field of hydraulic steering systems of special vehicles, and particularly relates to a device for automatically switching constant-pressure oil sources based on pressure judgment.
Background
In order to improve the maneuverability and flexibility of steering, a large-scale multi-axle vehicle generally adopts an electro-hydraulic steering scheme, an electro-hydraulic steering system is divided into a front axle loop and a rear axle loop, the front axle loop and the rear axle loop are not connected by a mechanical rod system, and the front axle loop and the rear axle loop are two mutually independent steering axles. Wherein the rear axle adopts the power-assisted to align the hydraulic cylinder and realize the power-assisted and align the function respectively. The traditional steering oil source adopts a constant delivery pump for supplying oil and a switching mode based on flow judgment, and realizes automatic switching of a main oil source and an emergency oil source by a current-limiting distribution safety valve. The flow difference required by the system is larger when the power-assisted alignment cylinder works in the power-assisted mode and the alignment mode, the piston moves in the power-assisted mode, the flow of the system is larger, the piston is always in the middle position in the alignment mode, and the flow of the system is close to zero. Therefore, the traditional oil source scheme cannot automatically adjust output flow according to system requirements, when the system requirements are low, most of flow output by the hydraulic pump returns to the oil tank through the overflow valve, and the problems of large heat productivity, low energy utilization rate, low system reliability and the like exist.
Disclosure of Invention
The technical problem solved by the invention is as follows: the defects of the prior art are overcome, the automatic switching constant-pressure oil source device based on pressure judgment is provided, the problem that the conventional oil source scheme cannot automatically adjust the output flow according to the system requirement is solved, when the system requirement is low, most of flow output by the hydraulic pump returns to an oil tank through an overflow valve, the heat productivity is high, the energy utilization rate is low, and the system reliability is low is solved.
The purpose of the invention is realized by the following technical scheme: an automatic switching constant pressure oil source device based on pressure judgment comprises: the emergency pump is connected with the first high-pressure filter and the second high-pressure filter; the oil tank is respectively connected with the constant-pressure variable pump, the emergency pump and the oil return filter through pipelines; the constant-pressure variable pump is connected with the first high-pressure filter through a pipeline, and the first high-pressure filter is connected with the oil source control unit through a pipeline; the oil source control unit is respectively connected with the oil return filter and the second high-pressure filter through pipelines; and the second high-pressure filter is connected with the emergency pump pipeline.
In the automatic switching constant-pressure oil source device based on pressure judgment, the oil source control unit comprises a flow dividing valve, an electromagnetic directional valve, a safety valve, a balance valve, a first one-way valve and a second one-way valve; one end of the flow divider is connected with the second high-pressure filter pipeline, and the other end of the flow divider is respectively connected with the balance valve and the first one-way valve pipeline; the balance valve is connected with the electromagnetic directional valve through a pipeline; the oil return filter is respectively connected with the balance valve and the electromagnetic reversing valve through pipelines; the electromagnetic directional valve is connected with the safety valve through a pipeline; the safety valve is respectively connected with the first one-way valve and the second one-way valve through pipelines; the second one-way valve is connected with the first high-pressure filter pipeline.
In the automatic switching constant pressure oil source device based on pressure judgment, the type of the oil tank is HTFYTK9901A04, and the volume is 925L.
In the automatic switching constant-pressure oil source device based on pressure judgment, the discharge capacity of the constant-pressure variable pump is 30ml/r, and the maximum working pressure is 35 MPa.
In the automatic switching constant-pressure oil source device based on pressure judgment, the maximum working flow of the emergency pump is 25L/min.
In the automatic switching constant-pressure oil source device based on pressure judgment, the maximum working flow of the first high-pressure filter is 110L/min, and the maximum working pressure is 25 MPa.
In the automatic switching constant-pressure oil source device based on pressure judgment, the maximum working flow of the second high-pressure filter is 60L/min, and the maximum working pressure is 25 MPa.
In the automatic switching constant-pressure oil source device based on pressure judgment, the maximum working flow of the oil return filter is 660L/min.
In the automatic switching constant-pressure oil source device based on pressure judgment, the working flow of the flow dividing valve is 20-120L/min, and the maximum working pressure is 35 MPa.
In the automatic switching constant-pressure oil source device based on pressure judgment, the maximum working flow of the electromagnetic directional valve is 120L/min, and the maximum working pressure is 35 MPa.
Compared with the prior art, the invention has the following beneficial effects:
(1) according to the invention, by adopting a scheme of combining the constant-pressure variable pump and the oil source control unit, the output flow can be automatically adjusted according to the system requirement, and when the boosting alignment cylinder works in a boosting mode, the pump is in a high-pressure large-flow state; when the boosting alignment cylinder works in an alignment mode, the oil source is in a high-pressure low-flow state, the system heating is effectively reduced, and the energy utilization rate is improved.
(2) The invention adopts the scheme that the constant-pressure variable pump and the emergency pump are mutually backed up, when the system normally works, the pressure at the outlet of the constant-pressure variable pump is higher than a set value, the system is supplied with oil by the constant-pressure variable pump, and the emergency pump unloads; when the constant-pressure variable pump fails, the system detects that the outlet pressure of the system is lower than a set value, the emergency pump stops unloading and supplies oil to the system, and the double-pump backup scheme greatly improves the reliability of the system.
(3) The integrated safe unloading device ensures that the system can be reliably unloaded when the system works no matter the constant-pressure variable pump or the emergency pump, and further ensures the safety of the system.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
FIG. 1 is a block diagram of an apparatus for automatically switching a constant pressure oil source based on pressure determination according to an embodiment of the present invention;
fig. 2 is a block diagram of an oil source control unit according to an embodiment of the present invention.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
FIG. 1 is a block diagram of an apparatus for automatically switching a constant pressure oil source based on pressure determination according to an embodiment of the present invention; as shown in fig. 1, the automatic switching constant pressure oil source device based on pressure determination includes an oil tank 1, a constant pressure variable pump 2, an emergency pump 3, a first high pressure filter 41, a second high pressure filter 42, an oil return filter 5, and an oil source control unit 6. Wherein,
the oil tank 1 is respectively connected with a constant pressure variable pump 2, an emergency pump 3 and an oil return filter 5 through pipelines; the constant pressure variable pump 2 is connected with a first high pressure filter 41 through a pipeline, and the first high pressure filter 41 is connected with an oil source control unit 6 through a pipeline; the oil source control unit 6 is respectively connected with the oil return filter 5 and the second high-pressure filter 42 through pipelines; the second high-pressure filter 42 is connected to the emergency pump 3.
Fig. 2 is a block diagram of an oil source control unit according to an embodiment of the present invention. As shown in fig. 2, the oil source control unit 6 includes a flow dividing valve 61, an electromagnetic directional valve 62, a relief valve 63, a balance valve 64, a first check valve 65, and a second check valve 66; wherein,
one end of the flow dividing valve 61 is connected with the second high-pressure filter 42 through a pipeline, and the other end of the flow dividing valve is respectively connected with the balance valve 64 and the first check valve 65 through pipelines; the balance valve 64 is connected with the electromagnetic directional valve 62 through a pipeline; the return oil filter 5 is respectively connected with the balance valve 64 and the electromagnetic directional valve 62 through pipelines; the electromagnetic directional valve 62 is connected with the safety valve 63 through a pipeline; the safety valve 63 is respectively connected with a first check valve 65 and a second check valve 66 through pipelines; the second check valve 66 is connected to the first high-pressure filter 41.
The constant pressure variable pump 2 is driven by an engine, the output pressure of the pump is a fixed value, and the output flow can be automatically adjusted according to the system requirement. The emergency pump 3 is driven by the transfer case, the flow of the emergency pump 3 is related to the rotation speed of the wheels, and when the rotation speed of the wheels is higher than a certain value, the flow of the emergency pump 3 is limited to the maximum value.
The oil source device mainly provides power for the front cylinder for the power assistance of the rear axle, when the rear axle is in a power assistance working mode, the flow required by the system is large, the displacement of the constant-pressure variable pump 2 is increased, the output flow is increased, and the outlet pressure is kept unchanged; when the rear axle is in the alignment mode, the piston of the alignment cylinder is kept in the alignment position by the aid of the power assistance, the flow demand of the system is close to zero, the displacement of the constant-pressure variable pump 2 is automatically adjusted to be minimum, the output flow is only used for maintaining the leakage of the system, and the pump works in a high-pressure waiting mode at the moment to ensure that the alignment cylinder is reliably aligned by the aid of the power assistance. By using the constant-pressure variable pump 2, the problem of large flow demand contradiction between cylinder alignment assistance and alignment assistance in two modes can be effectively solved, the overflow capacity and the heat productivity of the system are reduced, and the working reliability of the steering system is improved.
The oil source control unit 6 realizes automatic switching between the constant-pressure variable pump 2 and the emergency pump 3, and the principle thereof is as shown in fig. 2, and the oil source control unit is composed of a flow dividing valve 61, an electromagnetic directional valve 62, a safety valve 63, a balance valve 64, a first check valve 65, a second check valve 66 and the like. The port P1 is connected with a constant pressure variable pump 2 and the port P2 emergency pump 3, the emergency pump 3 is divided into two parts through a flow dividing valve 61 and respectively used as a front axle emergency oil source and a rear axle emergency oil source, the port A1 is used as system output, and the port O is used as an oil return port. The output flow of the constant-pressure variable pump 2 is changed along with the system requirement, but the outlet pressure is kept unchanged, and the automatic switching of the double backup oil sources is realized by adopting a pressure judgment-based method. The control unit 6 is integrated with a balance valve 64, a control port of the balance valve 64 is communicated with an outlet of the constant pressure variable pump 2, the balance valve 64 can be reversely opened by outlet pressure of the constant pressure variable pump 2 when the constant pressure variable pump 2 works normally by setting opening pressure of the balance valve 64, and the emergency pump 3 is unloaded from an O port through the balance valve. When the constant pressure variable pump 2 fails, the outlet pressure of the constant pressure variable pump decreases, the balance valve 64 cannot be opened, and the emergency pump 3 cannot be unloaded and enters the system through the first check valve 65 to supply oil to the system. Therefore, the oil source control unit 6 automatically judges the outlet pressure of the constant-pressure variable pump 2 mainly through the balance 64, so that the automatic switching between the constant-pressure variable pump 2 and the emergency pump 3 is realized, and the reliable work of a steering system is ensured.
Meanwhile, various safety protection measures are adopted in the oil source control unit 6 to ensure that all parts of the system are not damaged under extreme conditions. The safety valve 63 is mainly used as a system safety valve to limit the maximum pressure of the system not to exceed a set value; the reversing valve 62 is mainly used for manual unloading of the emergency pump 3, when the constant-pressure variable pump 2 fails and the emergency pump 3 works, the reversing valve 62 can be used for reversing to enable the emergency pump 3 to be directly communicated with an oil return port so as to unload, and the excessive heat productivity of the system is prevented when the emergency pump 3 works for a long time; the first check valve 65 and the second check valve 66 are respectively connected with the constant-pressure variable pump 2 and the emergency pump 3, so that mutual interference of two oil sources is prevented, and the constant-pressure variable pump 2 and the emergency pump 3 are effectively protected.
Further, the types and parameters of the above components are shown in the following table:
in the embodiment, by using a scheme of combining a constant-pressure variable pump and an oil source control unit, the output flow can be automatically adjusted according to the system requirement, and when the boosting alignment cylinder works in a boosting mode, the pump is in a high-pressure large-flow state; when the power-assisted alignment cylinder works in an alignment mode, the oil source is in a high-pressure low-flow state, so that the heating of a system is effectively reduced, and the energy utilization rate is improved; in the embodiment, a scheme of mutual backup of the constant-pressure variable pump and the emergency pump is adopted, when the system works normally, the pressure at the outlet of the constant-pressure variable pump is higher than a set value, the system is supplied with oil by the constant-pressure variable pump, and the emergency pump unloads; when the constant-pressure variable pump fails, the system detects that the outlet pressure of the system is lower than a set value, the emergency pump stops unloading and supplies oil to the system, and the double-pump backup scheme greatly improves the reliability of the system; the integrated safe unloading device of the embodiment can ensure reliable unloading of the system no matter the system is a constant-pressure variable pump or an emergency pump during working, and further ensure the safety of the system.
The above-described embodiments are merely preferred embodiments of the present invention, and general changes and substitutions by those skilled in the art within the technical scope of the present invention are included in the protection scope of the present invention.
Claims (10)
1. The utility model provides an automatic switch-over constant voltage oil source device based on pressure is judged which characterized in that includes: the emergency pump comprises an oil tank (1), a constant-pressure variable pump (2), an emergency pump (3), a first high-pressure filter (41), a second high-pressure filter (42), an oil return filter (5) and an oil source control unit (6); wherein,
the oil tank (1) is respectively connected with the constant-pressure variable pump (2), the emergency pump (3) and the oil return filter (5) through pipelines;
the constant-pressure variable pump (2) is connected with the first high-pressure filter (41) through a pipeline, and the first high-pressure filter (41) is connected with the oil source control unit (6) through a pipeline;
the oil source control unit (6) is respectively connected with the oil return filter (5) and the second high-pressure filter (42) through pipelines;
the second high-pressure filter (42) is connected with the emergency pump (3) through a pipeline.
2. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 1, wherein: the oil source control unit (6) comprises a flow dividing valve (61), an electromagnetic reversing valve (62), a safety valve (63), a balance valve (64), a first one-way valve (65) and a second one-way valve (66); wherein,
one end of the flow dividing valve (61) is connected with the second high-pressure filter (42) through a pipeline, and the other end of the flow dividing valve is respectively connected with the balance valve (64) and the first check valve (65) through pipelines;
the balance valve (64) is connected with the electromagnetic directional valve (62) through a pipeline;
the oil return filter (5) is respectively connected with the balance valve (64) and the electromagnetic directional valve (62) through pipelines;
the electromagnetic directional valve (62) is connected with the safety valve (63) through a pipeline;
the safety valve (63) is respectively connected with the first one-way valve (65) and the second one-way valve (66) through pipelines;
the second check valve (66) is connected with the first high-pressure filter (41) in a pipeline way.
3. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 1, wherein: the type of the oil tank (1) is HTFYTK9901A04, and the volume is 925L.
4. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 1, wherein: the discharge capacity of the constant-pressure variable pump (2) is 30ml/r, and the maximum working pressure is 35 MPa.
5. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 1, wherein: the maximum working flow of the emergency pump (3) is 25L/min.
6. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 1, wherein: the maximum working flow of the first high-pressure filter (41) is 110L/min, and the maximum working pressure is 25 MPa.
7. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 1, wherein: the maximum working flow of the second high-pressure filter (42) is 60L/min, and the maximum working pressure is 25 MPa.
8. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 1, wherein: the maximum working flow of the oil return filter (5) is 660L/min.
9. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 2, wherein: the working flow of the flow dividing valve (61) is 20-120L/min, and the maximum working pressure is 35 MPa.
10. The automatic switching constant pressure oil source device based on pressure judgment as claimed in claim 2, wherein: the maximum working flow of the electromagnetic directional valve (62) is 120L/min, and the maximum working pressure is 35 MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811270768.5A CN109253118A (en) | 2018-10-29 | 2018-10-29 | A kind of automatic switchover constant pressure oil source device based on pressure judgement |
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| CN201811270768.5A CN109253118A (en) | 2018-10-29 | 2018-10-29 | A kind of automatic switchover constant pressure oil source device based on pressure judgement |
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| CN201811270768.5A Pending CN109253118A (en) | 2018-10-29 | 2018-10-29 | A kind of automatic switchover constant pressure oil source device based on pressure judgement |
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Application publication date: 20190122 |
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