CN206439132U - High-pressure pump - Google Patents
High-pressure pump Download PDFInfo
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- CN206439132U CN206439132U CN201720100117.6U CN201720100117U CN206439132U CN 206439132 U CN206439132 U CN 206439132U CN 201720100117 U CN201720100117 U CN 201720100117U CN 206439132 U CN206439132 U CN 206439132U
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- pressure
- plunger
- paragraph
- plunger bushing
- pressure pump
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Abstract
The utility model provides a kind of high-pressure pump, the plunger bushing of the high-pressure pump includes first paragraph and the second segment being connected with first paragraph, projecting part is arranged at second segment on the outside of first paragraph, and first paragraph is located at first pressure intracavitary, and interference point position of the present utility model is moved down compared with prior art.In the pump oil stage, first paragraph is deformed inward contraction under the effect of its inside and outside differential pressure, and the gap shrinks between first paragraph and plunger effectively reduce the loss of clearance backflow；In the oil suction stage, inside and outside no pressure difference of first paragraph makes first paragraph recover the state to deformation by contraction state.Therefore, on the premise of with equal volumetric efficiency, compared with existing high-pressure pump, high-pressure pump of the present utility model has bigger plunger gap in oil suction stroke, less plunger pair abrasion, more life-span surpluses, so as to the further processing gap for reducing plunger pair to lift volumetric efficiency, without increase weight or the material using higher costs.
Description
Technical field
The utility model is related to oil spout pump technical field, more particularly to a kind of high-pressure pump.
Background technology
High-pressure pump is the vital part of direct fuel injection engine, as shown in figure 1, the high-pressure pump include inlet valve 5 ',
Delivery valve 6 ' and the pressure chamber 1 ' being arranged between the inlet valve 5 ' and delivery valve 6 ', it is arranged in the pressure chamber 1 '
Plunger bushing 3 ', is arranged at the projecting part 8 ' being connected on the outside of described plunger bushing one end and with the interference of pressure chamber 1 ', and be arranged at post
Plunger 4 ' on the inside of plug sleeve 3 ', sets up pressure by movement of the plunger 4 ' in pressure chamber 1 ', low-voltage fuel is converted into height
Compression ignition oil (150bar or more).
With the continuous lifting of energy-saving and emission-reduction requirement, manufacturing and designing for high-pressure pump is also faced with new challenges：Do not losing light weight
On the premise of change, it is desirable to further improve pump oil pressure (350bar or more).However, with the lifting of pressure, in pump oil rank
Duan Zhong, hydraulic oil is flowed back to low-pressure area by plunger gap (seal clearance of plunger-plunger bushing), causes what volumetric efficiency declined
Problem is further serious, and the problem is especially pronounced under slow-speed of revolution operating mode so that slow-speed of revolution supply capability has turned into higher pressure oil
The bottleneck ability of pump.
To solve problem above, currently employed scheme is as follows：
1. selecting bigger pump oil volume, the loss that volumetric efficiency descent tape is come is made up；
2. increasing the length of plunger gap section, the loss of clearance backflow is reduced；
3. reducing the processing gap (i.e. 7 ' the object referred in Fig. 1) of plunger pair (plunger and plunger bushing), reduce gap and return
The loss of stream.
Wherein, the cost that scheme 1,2 all increases along with weight, cost is improved；Scheme 3 then accelerates to grind along with plunger pair
Damage, the risk that is remarkably decreased of life-span is, it is necessary to enable wearability more preferably but price higher material or process of surface treatment.
Utility model content
The purpose of this utility model is to provide a kind of high-pressure pump, to improve using high-pressure pump in the prior art in pump oil rank
There is plunger gap in section and there is hydraulic oil and flowed back to low-pressure area, cause the problem of volumetric efficiency declines.
In order to solve the above technical problems, the utility model provides a kind of high-pressure pump, the high-pressure pump includes：Pressure chamber, set
The plunger bushing that is placed in the pressure chamber, it is arranged at the protrusion being connected on the outside of the plunger bushing and with the pressure chamber body wall interference
Part, the plunger being arranged in the plunger bushing, inlet valve and delivery valve；Wherein, the plunger bushing include first paragraph and with institute
The second segment of first paragraph connection is stated, the projecting part is arranged at the second segment on the outside of the first paragraph, described
The pressure chamber is divided into First pressure chamber and second pressure chamber by projecting part, and the first paragraph is located at first pressure intracavitary,
The inlet valve and the delivery valve may be contained within the First pressure chamber.
Optionally, in described high-pressure pump, the high-pressure pump pump oil stage, the plunger from the second pressure chamber to
First pressure chamber is moved.
Optionally, in described high-pressure pump, the high-pressure pump pump oil stage, the pressure of the first pressure intracavitary is higher than
The pressure of the second pressure intracavitary.
Optionally, in described high-pressure pump, the high-pressure pump pump oil stage, the first paragraph of the plunger bushing is deformed inward
Shrink, the gap between the first paragraph of the plunger bushing and the plunger is less than the processing gap of plunger pair.
Optionally, in described high-pressure pump, the high-pressure pump pump oil stage, the pressure of the first pressure intracavitary is to institute
Successively decrease in the direction for stating second pressure chamber.
Optionally, in described high-pressure pump, the high-pressure pump oil suction stage, the plunger from the First pressure chamber to
Second pressure chamber is moved.
Optionally, in described high-pressure pump, the high-pressure pump oil suction stage, the pressure of the first pressure intracavitary is equal to
The pressure of the second pressure intracavitary.
Optionally, in described high-pressure pump, the high-pressure pump oil suction stage, the first paragraph of the plunger bushing and the post
Gap between plug is equal to the gap between the second segment of the plunger bushing and the plunger, the second segment of the plunger bushing and institute
State the processing gap that the gap between plunger is plunger pair.
Optionally, in described high-pressure pump, the second segment of the internal diameter of the first paragraph of the plunger bushing and the plunger bushing
Internal diameter it is identical, the external diameter of the first paragraph of the plunger bushing is identical with the external diameter of the second segment of the plunger bushing.
Optionally, in described high-pressure pump, the second segment of the internal diameter of the first paragraph of the plunger bushing and the plunger bushing
Internal diameter it is identical, the external diameter of the first paragraph of the plunger bushing is different from the external diameter of the second segment of the plunger bushing.
Optionally, in described high-pressure pump, the length of the first paragraph of the plunger bushing and the total length of the plunger bushing
Meet following relation：
Wherein, L2 is the total length of the plunger bushing, and L1 is the length of the first paragraph of the plunger bushing.
Optionally, in described high-pressure pump, the internal diameter of the first paragraph of the plunger bushing, the first paragraph of the plunger bushing
The external diameter of external diameter and the second segment of the plunger bushing meets following relation：
Wherein, D1 is the internal diameter of the first paragraph of the plunger bushing, and D2 is the external diameter of the second segment of the plunger bushing, and D3 is institute
State the external diameter of the first paragraph of plunger bushing.
Optionally, in described high-pressure pump, the first paragraph is connected with the second segment by changeover portion, the transition
The section of section be rendered as in fillet, right angle, oblique angle, multistage curve, multistage straight line it is a kind of, or multistage curve and multistage straight line group
Close.
In high-pressure pump provided by the utility model, the plunger bushing of the high-pressure pump includes first paragraph and connected with first paragraph
The second segment connect, projecting part is arranged at second segment on the outside of first paragraph, and first paragraph is located at first pressure intracavitary, compares
Prior art interference point position of the present utility model is moved down.In the pump oil stage, first paragraph inwardly becomes under the effect of its inside and outside differential pressure
Shape is shunk, and the gap shrinks between first paragraph and plunger effectively reduce the loss of clearance backflow；In the oil suction stage, first paragraph
Inside and outside no pressure difference, makes first paragraph recover the state to deformation by contraction state.Therefore, before with equal volumetric efficiency
Put, compared with existing high-pressure pump, high-pressure pump of the present utility model has bigger plunger gap, less post in oil suction stroke
The secondary abrasion of plug, more life-span surpluses, so as to the further processing gap for reducing plunger pair to lift volumetric efficiency, without
Increase weight or the material using higher costs.Show pump oil pressure bigger, first paragraph deforms bigger, the increasing to volumetric efficiency
The beneficial more significant phenomenon of effect.
Brief description of the drawings
Fig. 1 is the structural representation of high-pressure pump in the prior art；
Fig. 2 is structural representation of the embodiment mesohigh pump of the utility model one at the pump oil stage；
Fig. 3 is structural representation of the embodiment mesohigh pump of the utility model one at the oil suction stage；
Fig. 4 is the diagrammatic cross-section of plunger bushing in the embodiment of the utility model one；
Fig. 5 a~5f is cuing open for the changeover portion between the first paragraph of plunger bushing in the embodiment of the utility model one and second segment
Face schematic diagram.
In Fig. 1：Pressure chamber 1 '；Plunger bushing 3 '；Plunger 4 '；Inlet valve 5 '；Delivery valve 6 '；The processing gap 7 ' of plunger pair；
Projecting part 8 '；
In Fig. 2-Fig. 4：First pressure chamber 1；Second pressure chamber 2；Plunger bushing 3；First paragraph 31；Second segment 32；Plunger 4；Enter
Fuel tap 5；Delivery valve 6；The processing gap 7 of plunger pair；Projecting part 8.
Embodiment
Below in conjunction with the drawings and specific embodiments to the utility model proposes high-pressure pump be described in further detail.According to
Illustrate below and claims, advantages and features of the present utility model will become apparent from.It should be noted that, accompanying drawing is using very
Simplified form and use non-accurately ratio, only to it is convenient, lucidly aid in illustrating the mesh of the utility model embodiment
's.
Fig. 2 and Fig. 4 is refer to, it is the structural representation of high-pressure pump of the present utility model, as shown in Fig. 2 the high pressure
Pump includes：Pressure chamber, the plunger bushing 3 being arranged in the pressure chamber, be arranged at the outside of the plunger bushing 3 and with the pressure chamber
Projecting part 8, the plunger 4 being arranged in the plunger bushing 3, inlet valve 5 and the delivery valve 6 of body wall interference connection；Wherein, it is described
Plunger bushing 3 includes first paragraph 31 and the second segment 32 being connected with the first paragraph 31, and the projecting part 8 is arranged at described second
Section 32 is on the outside of the first paragraph 31, and the pressure chamber is divided into First pressure chamber 1 and second by the projecting part 8
Pressure chamber 2, the first paragraph 31 is located in First pressure chamber 1, and the inlet valve 5 and the delivery valve 6 may be contained within described the
On one pressure chamber 1.
The projecting part is First pressure chamber 1 and the separation of second pressure chamber 2, comparative analysis as pressure chamber is divided
Projecting part 8 is compared the position of projecting part 8 ' in Fig. 1 and moved down in Fig. 1 and Fig. 2, Fig. 2, so that the plunger bushing 3 (i.e. the of predetermined length
One section) first pressure intracavitary, i.e. Fig. 2 are placed in compared to the structure shown in Fig. 1, add the plunger for being placed in first pressure intracavitary
Length is covered, there is plunger gap in the pump oil stage and there is hydraulic oil to improve high-pressure pump and flowed back to low-pressure area, cause volume to imitate
The problem of rate declines.
During high-pressure pump practical application, it is divided into pump oil stage and oil suction stage, the specific work process in two stages is as follows：
As shown in Fig. 2 in the pump oil stage, the plunger 4 is moved from the second pressure chamber 2 to First pressure chamber 1, so that
So that the pressure in the First pressure chamber 1 is higher than the pressure in the second pressure chamber 2, now, the interior external memory of first paragraph 31
In pressure differential, the direction for showing as pressure to the second pressure chamber 2 in the First pressure chamber 1 is successively decreased.Main cause exists
In：The outside of the first paragraph 31 of plunger bushing 3 is the high pressure constant pressure influence in First pressure chamber 1, the first paragraph 31 of the plunger bushing 3
Inner side connected with second pressure chamber 2, therefore the inner side of the first paragraph 31 of plunger bushing 3 pressure along the First pressure chamber 1 to
The direction of the second pressure chamber 2 is successively decreased and is less than the pressure that the outside of first paragraph 31 is subject to, in the presence of pressure differential, and first
Section 31 is deformed inward contraction, so that the gap between the first paragraph 31 and the plunger 4 of the plunger bushing 3 is less than plunger pair
Processing gap 7 (i.e. the original processing gap of plunger 4 and plunger bushing 3).
As shown in figure 3, in the oil suction stage, the plunger 4 is moved from the First pressure chamber 1 to second pressure chamber 2, so that
So that pressure in the First pressure chamber 1 is equal to the pressure in the second pressure chamber 2, therefore, first paragraph 31 it is inside and outside not
There is pressure differential, first paragraph 31 recovers the state to deformation from the pump oil stage to the state of contract, the plunger bushing 3
Gap between first paragraph 31 and the plunger 4 is equal to the gap between the second segment 32 of the plunger bushing 3 and the plunger 4
(being also the original state of plunger bushing 3), is equal to the processing gap 7 of plunger pair.It is preferred that, the processing gap 7 of the plunger pair
Width range be 1 μm~15 μm.
Therefore, on the premise of with the equal gap of pump oil stroke plunger 4 (that is, equal volumetric efficiency), with existing high pressure
Pump is compared, and high-pressure pump of the present utility model has bigger plunger gap in oil suction stroke, and the secondary abrasion of less plunger 4 is more
Life-span surplus, so as to further reduce plunger pair processing gap 7, further to lift volumetric efficiency.In other words, with
Loss of Life surplus is cost, the processing gap 7 of plunger pair is further reduced, to reduce gap loss.Need not increase weight or
Using the material of higher costs.Moreover, pump oil pressure is bigger, adaptive deformation is bigger, more aobvious to the gain effect of volumetric efficiency
Write, effectively improve fuel oil combustion utilization efficiency, save oil consumption.
Further, the internal diameter phase of the internal diameter of the first paragraph 31 of the plunger bushing 3 and the second segment 32 of the plunger bushing 3
Together, the external diameter of the external diameter of the first paragraph 31 of the plunger bushing 3 and the second segment 32 of the plunger bushing 3 is identical or different.This implementation
In example, the external diameter of the first paragraph 31 of preferably described plunger bushing 3 is different from the external diameter of the second segment 32 of the plunger bushing 3, so as to
First paragraph 31 is more easy to be deformed into contraction state in the pump oil stage.
Refer to Fig. 4, no matter the external diameter of the first paragraph 31 of the plunger bushing 3 and the second segment 32 of the plunger bushing 3 it is outer
Whether footpath is identical, all needs to meet the following relation of relation：
Wherein, L2 is the total length of the plunger bushing 3, and L1 is the length of the first paragraph 31 of the plunger bushing 3.
Please continue to refer to Fig. 4, in the external diameter and the second segment 32 of the plunger bushing 3 of the first paragraph 31 of the plunger bushing 3
, it is necessary to meet the following relation of relation during external diameter difference：
Wherein, D1 is the internal diameter of the first paragraph 31 of the plunger bushing 3, and D2 is the external diameter of the second segment 32 of the plunger bushing 3,
D3 is the external diameter of the first paragraph 31 of the plunger bushing 3.
Preferably, refer to Fig. 5 a~5f, the first paragraph is connected with the second segment by changeover portion, the changeover portion
Presence be easy to plunger bushing being installed in pressure chamber, it is bent that the section of the changeover portion is rendered as fillet, right angle, oblique angle, multistage
The combination of line, one kind in multistage straight line or multistage curve and multistage straight line.
To sum up, in high-pressure pump provided by the utility model, the plunger bushing of the high-pressure pump includes first paragraph and with first
The second segment of section connection, projecting part is arranged at second segment on the outside of first paragraph, and first paragraph is located at first pressure intracavitary,
Interference point position of the present utility model is moved down compared with prior art.In the pump oil stage, first paragraph under the effect of its inside and outside differential pressure to
Interior deformation retract, the gap shrinks between first paragraph and plunger effectively reduce the loss of clearance backflow；In oil suction stage, first
Inside and outside no pressure difference of section, makes first paragraph recover the state to deformation by contraction state.Therefore, with equal volumetric efficiency
On the premise of, compared with existing high-pressure pump, high-pressure pump of the present utility model has bigger plunger gap in oil suction stroke, less
Plunger pair abrasion, more life-span surpluses, so as to further reduce plunger pair processing gap to lift volumetric efficiency, and
Weight or the material using higher costs need not be increased.
Foregoing description is only the description to the utility model preferred embodiment, not to any limit of the utility model scope
Calmly, the those of ordinary skill in the utility model field does according to the disclosure above content any change, modification, belonging to right will
Seek the protection domain of book.
Claims (13)
1. a kind of high-pressure pump, it is characterised in that including：Pressure chamber, the plunger bushing being arranged in the pressure chamber, be arranged at it is described
Plunger bushing outside and the projecting part being connected with the pressure chamber body wall interference, the plunger being arranged in the plunger bushing, oil-feed
Valve and delivery valve；Wherein, the plunger bushing includes first paragraph and the second segment being connected with the first paragraph, and the projecting part is set
The second segment is placed on the outside of the first paragraph, the pressure chamber is divided into First pressure chamber by the projecting part
With second pressure chamber, the first paragraph is located at first pressure intracavitary, and the inlet valve and the delivery valve may be contained within described the
On one pressure chamber.
2. high-pressure pump as claimed in claim 1, it is characterised in that the high-pressure pump pump oil stage, the plunger is from described
Two pressure chambers are moved to First pressure chamber.
3. high-pressure pump as claimed in claim 2, it is characterised in that the high-pressure pump pump oil stage, the first pressure intracavitary
Pressure be higher than the second pressure intracavitary pressure.
4. high-pressure pump as claimed in claim 3, it is characterised in that the high-pressure pump pump oil stage, the first of the plunger bushing
Section is deformed inward contraction, and the gap between the first paragraph of the plunger bushing and the plunger is less than the processing gap of plunger pair.
5. high-pressure pump as claimed in claim 3, it is characterised in that the high-pressure pump pump oil stage, the first pressure intracavitary
The direction of from pressure to the second pressure chamber successively decrease.
6. high-pressure pump as claimed in claim 1, it is characterised in that the high-pressure pump oil suction stage, the plunger is from described
One pressure chamber is moved to second pressure chamber.
7. high-pressure pump as claimed in claim 6, it is characterised in that the high-pressure pump oil suction stage, the first pressure intracavitary
Pressure be equal to the second pressure intracavitary pressure.
8. high-pressure pump as claimed in claim 7, it is characterised in that the high-pressure pump oil suction stage, the first of the plunger bushing
Gap between section and the plunger is equal to the gap between the second segment of the plunger bushing and the plunger, the plunger bushing
Gap between second segment and the plunger is the processing gap of plunger pair.
9. high-pressure pump as claimed in claim 1, it is characterised in that the internal diameter of the first paragraph of the plunger bushing and the plunger bushing
Second segment internal diameter it is identical, the external diameter of the first paragraph of the plunger bushing is identical with the external diameter of the second segment of the plunger bushing.
10. high-pressure pump as claimed in claim 1, it is characterised in that the internal diameter of the first paragraph of the plunger bushing and the plunger
The internal diameter of the second segment of set is identical, and the external diameter of the first paragraph of the plunger bushing is different from the external diameter of the second segment of the plunger bushing.
11. the high-pressure pump as described in claim 9 or 10, it is characterised in that the length of the first paragraph of the plunger bushing with it is described
The total length of plunger bushing meets following relation：
<mrow>
<mn>3</mn>
<mo><</mo>
<mfrac>
<mrow>
<mi>L</mi>
<mn>2</mn>
</mrow>
<mrow>
<mi>L</mi>
<mn>1</mn>
</mrow>
</mfrac>
<mo><</mo>
<mn>8</mn>
<mo>;</mo>
</mrow>
Wherein, L2 is the total length of the plunger bushing, and L1 is the length of the first paragraph of the plunger bushing.
12. high-pressure pump as claimed in claim 10, it is characterised in that the internal diameter of the first paragraph of the plunger bushing, the plunger
The external diameter of the external diameter of the first paragraph of set and the second segment of the plunger bushing meets following relation：
<mrow>
<mfrac>
<mrow>
<mi>D</mi>
<mn>2</mn>
<mo>-</mo>
<mi>D</mi>
<mn>1</mn>
</mrow>
<mrow>
<mi>D</mi>
<mn>3</mn>
<mo>-</mo>
<mi>D</mi>
<mn>1</mn>
</mrow>
</mfrac>
<mo>></mo>
<mn>1.2</mn>
<mo>;</mo>
</mrow>
Wherein, D1 is the internal diameter of the first paragraph of the plunger bushing, and D2 is the external diameter of the second segment of the plunger bushing, and D3 is the post
The external diameter of the first paragraph of plug sleeve.
13. high-pressure pump as claimed in claim 12, it is characterised in that the first paragraph is connected with the second segment by changeover portion
Connect, the section of the changeover portion be rendered as in fillet, right angle, oblique angle, multistage curve, multistage straight line it is a kind of, or multistage curve with
The combination of multistage straight line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720100117.6U CN206439132U (en) | 2017-01-23 | 2017-01-23 | High-pressure pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720100117.6U CN206439132U (en) | 2017-01-23 | 2017-01-23 | High-pressure pump |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206439132U true CN206439132U (en) | 2017-08-25 |
Family
ID=59636304
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720100117.6U Active CN206439132U (en) | 2017-01-23 | 2017-01-23 | High-pressure pump |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN206439132U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106762299A (en) * | 2017-01-23 | 2017-05-31 | 联合汽车电子有限公司 | High-pressure pump |
-
2017
- 2017-01-23 CN CN201720100117.6U patent/CN206439132U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106762299A (en) * | 2017-01-23 | 2017-05-31 | 联合汽车电子有限公司 | High-pressure pump |
| WO2018133876A1 (en) * | 2017-01-23 | 2018-07-26 | 联合汽车电子有限公司 | High-pressure pump |
| CN106762299B (en) * | 2017-01-23 | 2023-06-20 | 联合汽车电子有限公司 | High-pressure pump |
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