CN107701535B - Oil pumping and pressurizing assembly for tractor plunger pump - Google Patents
Oil pumping and pressurizing assembly for tractor plunger pump Download PDFInfo
- Publication number
- CN107701535B CN107701535B CN201710812436.4A CN201710812436A CN107701535B CN 107701535 B CN107701535 B CN 107701535B CN 201710812436 A CN201710812436 A CN 201710812436A CN 107701535 B CN107701535 B CN 107701535B
- Authority
- CN
- China
- Prior art keywords
- oil
- plunger pump
- pump
- gear pump
- plunger
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
- 238000005086 pumping Methods 0.000 title claims abstract description 9
- 238000010521 absorption reaction Methods 0.000 claims abstract description 14
- 239000003921 oil Substances 0.000 abstract description 152
- 239000010720 hydraulic oil Substances 0.000 abstract description 20
- 230000007246 mechanism Effects 0.000 abstract description 6
- 239000012535 impurity Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 231100000719 pollutant Toxicity 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
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
-
- 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
- F15B20/00—Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
- F15B20/007—Overload
-
- 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
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/04—Special measures taken in connection with the properties of the fluid
- F15B21/041—Removal or measurement of solid or liquid contamination, e.g. filtering
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20538—Type of pump constant capacity
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20576—Systems with pumps with multiple pumps
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Details Of Reciprocating Pumps (AREA)
Abstract
The invention relates to the field of agricultural machinery, in particular to an oil pumping and pressurizing assembly of a plunger piston of a tractor. The hydraulic oil pump comprises a plunger pump and a gear pump, wherein the gear pump is arranged between the plunger pump and an oil tank, an oil inlet of the gear pump is connected with the oil tank, an oil outlet of the gear pump is connected with an oil inlet oil path of the plunger pump, the gear pump is parallelly connected with a pressure protection valve which ensures that the oil absorption pressure of the plunger pump is positive pressure, and two ends of the pressure protection valve are respectively connected with the oil inlet oil path and the oil outlet oil path of the gear pump. When the whole pressurizing system works, the gear pump is arranged between the plunger pump and the oil tank, hydraulic oil is firstly absorbed by the gear pump from the oil tank and is conveyed to the plunger pump, oil support is provided for the plunger pump, meanwhile, the pressure protection valve for ensuring that the plunger pump is positive pressure is arranged in parallel due to the fact that the gear pump is connected in parallel, so that the oil absorption pressure of the plunger pump is positive, the air absorption is effectively avoided, and the actuating mechanism driven by the plunger pump is ensured to obtain hydraulic oil with stable flow.
Description
Technical Field
The invention relates to the field of agricultural machinery, in particular to an oil pumping and pressurizing assembly of a plunger piston of a tractor.
Background
At present, an energy-saving load sensitive system is generally adopted in a high-power tractor hydraulic system, and a variable plunger pump is used for driving all actuating mechanisms, so that the flow is provided according to actual needs, and the purpose of energy saving is achieved. The displacement of the plunger pump is larger, the requirement on oil absorption is higher, the self-absorption capacity of the existing plunger pump is weaker, the unstable oil absorption is easy to occur in work, the oil supply of hydraulic oil is unstable, and a negative pressure suction state is generated.
Disclosure of Invention
The invention aims to solve the technical problem of providing an oil suction and pressurization assembly of a plunger pump of a tractor, which solves the problem that the pumping oil of the plunger pump is in a negative pressure suction state.
The technical scheme for solving the technical problems is as follows: the utility model provides a tractor plunger pump oil pumping pressure boost subassembly, includes plunger pump and gear pump, the gear pump sets up between plunger pump and the oil tank, the gear pump oil inlet with the oil tank is connected, the oil-out of gear pump with the oil inlet oil circuit of plunger pump is connected, the gear pump parallelly connected is provided with the assurance the plunger pump is the pressure protection valve of positive pressure, pressure protection valve both ends respectively with the oil inlet and the oil-out oil circuit of gear pump are connected.
Further, the pressure protection valve is a second one-way valve, an oil inlet of the second one-way valve is connected with an oil outlet oil way of the gear pump, and an oil outlet of the second one-way valve is connected with an oil way of the oil tank.
Further, an oil outlet of the gear pump is provided with a filter, and the filter is connected with an oil path of the gear pump.
Further, the filter is provided with a first one-way valve in parallel, an oil inlet of the first one-way valve is connected with an oil inlet of the filter, an oil outlet of the first one-way valve is connected with an oil outlet of the filter, and the first one-way valve allows oil to flow from the oil inlet to the oil outlet in a one-way manner.
Further, the plunger pump oil outlet is provided with an overload protection component, an oil inlet of the overload protection component is connected with an oil way of the plunger pump oil outlet, and an oil outlet of the overload protection component is connected with an oil way of an oil tank.
Further, the overload protection component is an overflow valve.
The invention provides a tractor plunger pump oil pumping and pressurizing assembly which comprises a plunger pump and a gear pump, wherein the gear pump is arranged between the plunger pump and an oil tank, an oil inlet of the gear pump is connected with the oil tank, an oil outlet of the gear pump is connected with an oil inlet oil way of the plunger pump, a pressure protection valve for ensuring that the plunger pump is positive pressure is arranged in parallel with the gear pump, and two ends of the pressure protection valve are respectively connected with an oil inlet of the gear pump and an oil outlet oil way of the plunger pump. Therefore, when the whole pressurizing system works, as the gear pump is arranged between the plunger pump and the oil tank, the gear pump firstly absorbs hydraulic oil from the oil tank and conveys the absorbed hydraulic oil to the plunger pump, oil is provided for the plunger pump, the oil provided by the gear pump is always larger than the oil required by the plunger pump, and redundant oil flows back to the oil suction port through the second one-way valve. Meanwhile, the gear pump is provided with the pressure protection valve which ensures that the oil suction pressure of the plunger pump is positive in parallel, so that the oil suction pressure of the plunger pump is positive, the suction is effectively avoided, and the hydraulic oil with stable flow can be obtained by an actuating mechanism driven by the plunger pump. Compared with the prior art, the method has the advantages that: the oil suction pressure of the plunger pump is positive, so that the suction is effectively avoided.
Drawings
Fig. 1 is a schematic diagram of a connection structure of a tractor plunger pump oil absorption pressurization assembly according to the present invention.
In the drawings, the list of components represented by the various numbers is as follows:
1. gear pump, 2, filter, 3, first check valve, 4, second check valve, 5, overflow valve, 6, plunger pump.
Detailed Description
The principles and features of the present invention are described below with reference to the drawings, the examples are illustrated for the purpose of illustrating the invention and are not to be construed as limiting the scope of the invention.
In the description of the present invention, it should be understood that the terms "upper," "lower," "center," "inner," "outer," "top," "bottom," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the invention and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
As shown in fig. 1, the invention provides a tractor plunger pump oil pumping and pressurizing assembly, which comprises a plunger pump 6 and a gear pump 1, wherein the gear pump 1 is arranged between the plunger pump 6 and an oil tank, an oil inlet of the gear pump 1 is connected with the oil tank, an oil outlet of the gear pump 1 is connected with an oil inlet oil path of the plunger pump 6, the gear pump 1 is provided with a pressure protection valve in parallel for ensuring positive pressure of the plunger pump 6, and two ends of the pressure protection valve are respectively connected with the oil inlet and the oil outlet oil path of the gear pump 1. Thus, when the whole pressurizing system works, as the gear pump 1 is arranged between the plunger pump 6 and the oil tank, the gear pump 1 firstly absorbs hydraulic oil from the oil tank and conveys the absorbed hydraulic oil to the plunger pump 6 to provide oil for the plunger pump 6, the oil provided by the gear pump is always larger than the oil required by the plunger pump, and the redundant oil flows back to the oil suction port through the second one-way valve 4. Meanwhile, the gear pump 1 is provided with the pressure protection valve which ensures that the oil suction pressure of the plunger pump 6 is positive in parallel, so that the oil suction pressure of the plunger pump 6 is positive, the suction is effectively avoided, and the hydraulic oil with stable flow can be obtained by an actuating mechanism driven by the plunger pump 6. Compared with the prior art, the method has the advantages that: the oil suction pressure of the plunger pump 6 is positive, so that the suction is effectively avoided.
The oil absorption and pressurization assembly of the plunger pump of the tractor, as shown in fig. 1, can be based on the technical scheme described above: the pressure protection valve is a second one-way valve 4, an oil inlet of the second one-way valve 4 is connected with an oil outlet oil way of the gear pump 1, and an oil outlet of the second one-way valve 4 is connected with an oil tank oil way. Like this, second check valve 4 oil inlet is connected with gear pump 1 oil-out oil circuit, second check valve 4 oil-out is connected with the oil tank oil circuit, it is understood that second check valve 4 allows the unidirectional flow of fluid to the oil-out from the oil inlet of second check valve 4, when plunger pump 6 absorbs oil, because the circulation direction of second check valve 4 for the plunger can only absorb oil from gear pump 1, gear pump 1 provides the hydraulic oil of malleation for plunger pump 6, on the oil circuit that second check valve 4 is located, when gear pump 1 oil pressure is too high, excessive hydraulic oil flows back to the hydraulic tank from second check valve 4, under the prerequisite of guaranteeing the oil demand of plunger pump 6, furthest reduces the oil pressure load of plunger pump 6, in order to guarantee the life of plunger pump 6.
The oil absorption and pressurization assembly of the plunger pump of the tractor, as shown in fig. 1, can be based on the technical scheme described above: an oil outlet of the gear pump 1 is provided with a filter 2, and the filter 2 is in oil circuit connection with the gear pump 1. The quality of hydraulic oil has great influence on the working performance of a hydraulic system, the root cause of a plurality of faults is from the hydraulic oil, the hydraulic oil filter 2 is arranged at a proper place for preventing the pollution of the oil, the pollutants in the oil can be trapped, the oil can be kept clean, and the normal operation of the oil system is ensured. According to the application, the filter 2 is arranged at the oil outlet of the gear pump 1, so that the hydraulic oil flowing from the gear pump 1 to the plunger pump 6 can be effectively ensured to pass through the filter 2 to be filtered, the filtered hydraulic oil flows to the plunger pump 6, and the hydraulic oil is driven to each executing mechanism through the plunger pump 6. The further preferable technical scheme is as follows: the filter 2 is provided with a first one-way valve 3 in parallel, an oil inlet of the first one-way valve 3 is connected with an oil inlet of the filter 2, an oil outlet of the first one-way valve 3 is connected with an oil outlet of the filter 2, and the first one-way valve 3 allows oil to flow from the oil inlet to the oil outlet in a one-way manner. In general, the pressurized oil from the gear pump 1 is fed to the plunger pump through the filter 2, and the first check valve 3 is closed. In a hydraulic system, a filter 2 belongs to a consumable element, a large amount of impurities are easily accumulated in the filter 2 after long-time use, and the impurities block a filter element in the filter 2, so that the flow of oil passing through the filter element in the filter 2 is influenced, and further the oil absorption of a plunger pump 6 is not smooth; the filter 2 is connected with the first one-way valve 3 in parallel, the first one-way valve 3 allows oil to flow from an oil inlet to an oil outlet, under the condition that the filter 2 is blocked, the pressure of the oil outlet of the gear pump 1 is increased, at the moment, the first one-way valve 3 is opened, the oil is allowed to pass through the first one-way valve 3 and flow to the plunger pump 6, and the plunger pump 6 can be guaranteed to be normally supplied with oil.
The oil absorption and pressurization assembly of the plunger pump of the tractor, as shown in fig. 1, can be based on the technical scheme described above: the oil outlet of the plunger pump 6 is provided with an overload protection part, the oil inlet of the overload protection part is connected with the oil circuit of the oil outlet of the plunger pump 6, and the oil outlet of the overload protection part is connected with the oil circuit of the oil tank. Thus, an overload protection component is arranged at the oil outlet of the plunger pump 6, and when the oil quantity provided by the plunger pump 6 is larger than the oil quantity required by an actuating mechanism in the system, the overload protection component conveys excessive hydraulic oil into the oil tank so as to protect the working pressure of the hydraulic system in a normal state. The further preferable technical scheme is as follows: the overload protection component is an overflow valve 5. Thus, when the amount of oil provided by the plunger pump 6 is larger than the amount of oil required by an actuator in the system, the relief valve 5 is opened, and the relief valve 5 delivers excess hydraulic oil from the oil drain port into the oil tank to protect the working pressure of the hydraulic system in a normal state.
The foregoing description of the preferred embodiments of the invention is not intended to limit the invention to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the invention are intended to be included within the scope of the invention.
Claims (4)
1. A tractor plunger pump oil pumping and pressurizing assembly, characterized in that: the oil pump comprises a plunger pump (6) and a gear pump (1), wherein the gear pump (1) is arranged between the plunger pump (6) and an oil tank, an oil inlet of the gear pump (1) is connected with the oil tank, an oil outlet of the gear pump (1) is connected with an oil inlet oil way of the plunger pump (6), the gear pump (1) is provided with a pressure protection valve which ensures that the oil suction pressure of the plunger pump (6) is positive pressure in parallel, and two ends of the pressure protection valve are respectively connected with the oil inlet and the oil outlet oil way of the gear pump (1); the pressure protection valve is a second one-way valve (4), an oil inlet of the second one-way valve (4) is connected with an oil outlet oil way of the gear pump (1), and an oil outlet of the second one-way valve (4) is connected with an oil tank oil way; an oil outlet of the gear pump (1) is provided with a filter (2), and the filter (2) is connected with an oil way of the gear pump (1).
2. The tractor plunger pump oil absorption pressurization assembly of claim 1, wherein: the filter (2) is provided with a first one-way valve (3) in parallel, an oil inlet of the first one-way valve (3) is connected with an oil inlet of the filter (2), an oil outlet of the first one-way valve (3) is connected with an oil outlet of the filter (2), and the first one-way valve (3) allows oil to flow from the oil inlet to the oil outlet in a one-way manner.
3. The tractor plunger pump oil absorption pressurization assembly of claim 1, wherein: an oil outlet of the plunger pump (6) is provided with an overload protection component, an oil inlet of the overload protection component is connected with an oil outlet oil way of the plunger pump (6), and an oil outlet of the overload protection component is connected with an oil tank oil way.
4. The tractor plunger pump oil absorption pressurization assembly of claim 3, wherein: the overload protection component is an overflow valve (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710812436.4A CN107701535B (en) | 2017-09-11 | 2017-09-11 | Oil pumping and pressurizing assembly for tractor plunger pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710812436.4A CN107701535B (en) | 2017-09-11 | 2017-09-11 | Oil pumping and pressurizing assembly for tractor plunger pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107701535A CN107701535A (en) | 2018-02-16 |
| CN107701535B true CN107701535B (en) | 2024-04-19 |
Family
ID=61172510
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710812436.4A Active CN107701535B (en) | 2017-09-11 | 2017-09-11 | Oil pumping and pressurizing assembly for tractor plunger pump |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107701535B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108716487B (en) * | 2018-06-11 | 2020-02-11 | 雷沃重工股份有限公司 | Tractor and common oil hydraulic system thereof |
| CN108916136B (en) * | 2018-08-06 | 2024-05-14 | 泉州鑫豪工程机械科技有限公司 | Hydraulic system of mini-excavator |
| CN113027869B (en) * | 2021-03-08 | 2023-03-14 | 潍柴雷沃智慧农业科技股份有限公司 | Oil suction and return filtering system and method and tractor |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007178004A (en) * | 2007-03-07 | 2007-07-12 | Toshiba Corp | Liquid pressure generator |
| CN202348639U (en) * | 2011-12-12 | 2012-07-25 | 中联重科股份有限公司 | Auxiliary starting type hydraulic oil supply unit for swash plate axial plunger pump and engineering machine |
| CN203144016U (en) * | 2013-04-15 | 2013-08-21 | 宁波赛维思机械有限公司 | Ultrahigh voltage electric hydraulic pump station |
| CN204921540U (en) * | 2015-09-01 | 2015-12-30 | 浙江大学 | Hydraulic pressure cavitation test system |
| CN206290512U (en) * | 2016-12-29 | 2017-06-30 | 旭孚（北京）新能源科技有限公司 | A kind of groove type heat collector single-motor double pump type hydraulic drive component |
| CN207178342U (en) * | 2017-09-11 | 2018-04-03 | 雷沃重工股份有限公司 | A kind of tractor plunger pump oil suction pressurizing pack |
-
2017
- 2017-09-11 CN CN201710812436.4A patent/CN107701535B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007178004A (en) * | 2007-03-07 | 2007-07-12 | Toshiba Corp | Liquid pressure generator |
| CN202348639U (en) * | 2011-12-12 | 2012-07-25 | 中联重科股份有限公司 | Auxiliary starting type hydraulic oil supply unit for swash plate axial plunger pump and engineering machine |
| CN203144016U (en) * | 2013-04-15 | 2013-08-21 | 宁波赛维思机械有限公司 | Ultrahigh voltage electric hydraulic pump station |
| CN204921540U (en) * | 2015-09-01 | 2015-12-30 | 浙江大学 | Hydraulic pressure cavitation test system |
| CN206290512U (en) * | 2016-12-29 | 2017-06-30 | 旭孚（北京）新能源科技有限公司 | A kind of groove type heat collector single-motor double pump type hydraulic drive component |
| CN207178342U (en) * | 2017-09-11 | 2018-04-03 | 雷沃重工股份有限公司 | A kind of tractor plunger pump oil suction pressurizing pack |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107701535A (en) | 2018-02-16 |
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Address after: 261206 No. 192 South Beihai Road, Fangzi District, Shandong, Weifang Applicant after: Weichai leiwo Heavy Industry Co.,Ltd. Address before: 261206 No. 192 South Beihai Road, Fangzi District, Shandong, Weifang Applicant before: LOVOL HEAVY INDUSTRY Co.,Ltd. |
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Address after: 261206 No. 192 South Beihai Road, Fangzi District, Shandong, Weifang Applicant after: Weichai Lovol Intelligent Agricultural Technology Co.,Ltd. Address before: 261206 No. 192 South Beihai Road, Fangzi District, Shandong, Weifang Applicant before: Weichai leiwo Heavy Industry Co.,Ltd. |
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