Oil delivery pump plunger and barrel assembly and high-pressure common-rail fuel injection pump
By adopting an oblique connecting channel and arc transition design in the high-pressure common rail fuel injection pump of the diesel engine, the problem of reduced mechanical strength caused by concentrated fuel pressure is solved, and the stability of high-pressure fuel output and the improvement of mechanical performance are achieved.
Patent Information
- Application Number
- CN202423324154.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-10-24
- Estimated Expiration
- 2034-12-31
AI Technical Summary
In existing diesel engine high-pressure common rail fuel injection pumps, the sharp corners in the fuel passage are prone to excessive fuel pressure concentration, leading to pressure fluctuations and reduced mechanical strength, posing a safety hazard.
Design an oil pump plunger assembly with an oblique connecting channel that connects to the fuel chamber and an arc transition at the connection point, with a radius ranging from 1.5mm to 2.5mm, preferably 2mm, and an acute angle of 60° to reduce impact stress and local stress concentration.
It improves the stability of fuel output and mechanical properties, avoids pressure shocks, enhances the strength of parts, simplifies production, and improves quality control efficiency.
Smart Images
Figure CN223469360U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a kind of oil transfer pump plunger pair and high-pressure common rail fuel injection pump. BACKGROUND
[0002] Diesel engine high-pressure common rail fuel injection pump is mainly used for matching diesel engine, and is installed to the power assembly of bus, truck etc. with diesel as fuel. Diesel engine high-pressure common rail fuel injection pump is composed of pump body component, oil transfer pump, camshaft and several components. Among them, plunger pair is composed of plunger sleeve and plunger, and is functional component for providing fuel injection. Low-pressure fuel is inhaled by the up and down movement of plunger, and high-pressure fuel is supplied.
[0003] In prior art, high-pressure fuel cavity in plunger sleeve is communicated with high-pressure output port through inclined hole. In existing design, high-pressure cavity is directly communicated with inclined hole, and the radius R of connecting part is about 0. When fuel engine needs higher fuel pressure (for example, pressure reaches 200MPa), internal fuel pressure is large, and sharp corner part in internal fuel passage is prone to excessive concentration of fuel pressure, so that pressure impact is directly generated on the part when high-pressure fuel is output, not only fuel pressure is fluctuated, but also mechanical strength of part is reduced, which brings safety hazard to use of high-pressure common rail fuel injection pump. UTILITY MODEL CONTENT
[0004] The utility model solves the technical problem that internal passage junction is prone to concentrate larger stress and reduce mechanical performance in prior art, and provides an oil transfer pump plunger pair and high-pressure common rail fuel injection pump.
[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme:
[0006] An oil transfer pump plunger pair, characterized in that: it includes plunger sleeve and plunger, first fuel cavity and first output port are arranged in the plunger sleeve, the plunger penetrates the first fuel cavity, the first fuel cavity and the first output port are communicated through inclined connecting hole, the connecting part of the inclined connecting hole and the first fuel cavity is provided with circular arc transition, and the radius of the circular arc transition ranges from
[0007] 1.5mm to 2.5mm.
[0008] Preferably, the radius of the circular arc transition is 2mm, the internal diameter of the first fuel cavity is 8.5mm, and the internal diameter of the inclined connecting hole is 4mm.
[0009] Preferably, the acute angle between the central axis of the inclined connecting hole and the central axis of the first fuel cavity is 60°.
[0010] Preferably, one end of the oblique connecting hole is connected to the bottom of the first output port, and the other end of the oblique connecting hole is connected to the side wall of the first fuel cavity.
[0011] The utility model discloses still provide a kind of high-pressure common rail fuel injection pump, its characterized in that: it includes pump body and camshaft, and the oil pump plunger pair of any one described above, the oil pump plunger pair and the camshaft respectively on the pump body described, the plunger of the oil pump plunger pair with the cam on the camshaft one-to-one correspondence, and linear reciprocating motion is presented with the rotation of the cam.
[0012] The above technical solution can achieve the following beneficial effects: The oil pump plunger pair in the utility model reduces impact stress and local stress concentration by enlarging the fillet, prevents the generation of internal cracks in the fuel passage, improves mechanical properties, makes the output of 200MPa high-pressure fuel more stable, improves the quality of the fuel pump, increases the angle of the fillet, simplifies the difficulty of subsequent deburring and control of the collapse amount, improves the production efficiency of the plunger sleeve, and ensures the quality control of the plunger sleeve. The high-pressure common rail fuel injection pump in the utility model avoids pressure impact when low-pressure fuel is input and high-pressure fuel is output, the high-pressure fuel output is more stable, the strength of the parts is also enhanced, and the mechanical properties of the plunger sleeve are improved. BRIEF DESCRIPTION OF DRAWINGS
[0013] Figure 1 It is a sectional view of the oil pump plunger pair of the preferred embodiment in the utility model.
[0014] Figure 2 It is a structural schematic view of the high-pressure common rail fuel injection pump of the preferred embodiment in the utility model. DETAILED DESCRIPTION
[0015] The utility model will be further described by way of examples below, but it is not limited to the scope of the examples.
[0016] In the description of the utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the utility model and 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 therefore cannot be understood as a limitation on the utility model.
[0017] As Figure 1As shown, the fuel delivery pump plunger pair in the embodiment includes a plunger sleeve 1 and a plunger (not shown in the figure), and a first fuel cavity 11 and a first output port 14 are arranged in the plunger sleeve 1, and the plunger penetrates through the first fuel cavity 11; the first fuel cavity 11 and the first output port 14 are communicated through a diagonal connecting channel 12, the inner diameter of the first fuel cavity 11 is 8.5 mm, and the inner diameter of the diagonal connecting channel 12 is 4 mm. An arc transition 13 is arranged at the connecting part of the diagonal connecting channel 12 and the first fuel cavity 11, and the radius of the arc transition 13 is 2 mm. Of course, in other embodiments, the radius can be preferably set to be 1.5 mm-2.5 mm.
[0018] The acute angle between the central axis of the diagonal connecting channel 12 and the central axis of the first fuel cavity 11 is 60°. The upper end of the diagonal connecting channel 12 is connected to the bottom of the first output port 14, and the lower end of the diagonal connecting channel 12 is connected to the side wall of the first fuel cavity 11. The arc transition 13 is arranged at the connecting part of the lower end of the diagonal connecting channel 12 and the first fuel cavity 11.
[0019] The embodiment also provides a high-pressure common rail fuel injection pump provided with the fuel delivery pump plunger pair. The high-pressure common rail fuel injection pump includes a pump body 2, a camshaft, and the fuel delivery pump plunger pair. The fuel delivery pump plunger pair and the camshaft are arranged on the pump body 2 respectively, the plunger of the fuel delivery pump plunger pair corresponds to the cam on the camshaft one by one, and performs linear reciprocating motion with the rotation of the cam. A fuel delivery pump 3 is also connected to the pump body 2, and the common rail fuel injection pump sucks low-pressure fuel into the first fuel cavity 11, compresses the fuel, and then sprays the required high-pressure fuel from the first output port 14 into the common rail through the diagonal connecting channel 12. The fuel delivery pump plunger pair in the embodiment can meet the requirement of outputting oil pressure of 200 MPa, and will not cause stress concentration cracks at the connecting part of the diagonal connecting channel 12 and the first fuel cavity 11 due to excessively high output oil pressure.
[0020] The fuel delivery pump plunger pair in the embodiment reduces the problems of impact stress and local stress concentration by enlarging the round angle of the arc transition, prevents the generation of internal cracks of the fuel passage, improves the mechanical performance, makes the output of 200 MPa high-pressure fuel more stable, improves the quality of the fuel pump, increases the angle of the round angle, simplifies the difficulty of subsequent deburring and control of the collapse amount, improves the production efficiency of the plunger sleeve, and guarantees the quality control of the plunger sleeve. The high-pressure common rail fuel injection pump in the embodiment avoids the pressure impact when low-pressure fuel is input and high-pressure fuel is output, the output of high-pressure fuel is more stable, the strength of the part is also enhanced, and the mechanical performance of the plunger sleeve is improved.
[0021] Although the specific embodiments of the present application are described above, those skilled in the art should understand that this is only an example, the protection scope of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present application, but these changes and modifications all fall within the protection scope of the present application.
Claims
1. An oil transfer pump plunger pair characterized by: It includes a plunger sleeve and a plunger, a first fuel cavity and a first output port are arranged in the plunger sleeve, and the plunger penetrates the first fuel cavity; The first fuel cavity and the first output port are communicated through a diagonal connecting channel, and a circular arc transition is arranged at a connecting part of the diagonal connecting channel and the first fuel cavity, and the radius of the circular arc transition ranges from 1.5 mm to 2.5 mm.
2. The fuel pump plunger pair of claim 1 wherein: The radius of the circular arc transition is 2 mm, the inner diameter of the first fuel cavity is 8.5 mm, and the inner diameter of the diagonal connecting channel is 4 mm.
3. The fuel pump plunger pair of claim 2 wherein: The acute angle between the central axis of the diagonal connecting channel and the central axis of the first fuel cavity is 60°.
4. The fuel pump plunger pair of claim 3 wherein: One end of the diagonal connecting channel is connected to the bottom of the first output port, and the other end of the diagonal connecting channel is connected to the side wall of the first fuel cavity.
5. A high-pressure common-rail fuel injection pump characterized by comprising: It includes a pump body and a camshaft, and the fuel pump plunger pair of any one of claims 1-4, the fuel pump plunger pair and the camshaft are arranged on the pump body respectively, the plunger of the fuel pump plunger pair corresponds to the cam on the camshaft one by one, and linear reciprocating motion is realized with the rotation of the cam.