CN214577481U - High-pressure in-line plunger pump and high-pressure common rail fuel injection system - Google Patents

Abstract

The utility model discloses a high pressure in-line plunger pump, include: the oil pump, the eccentric driving mechanism, the plunger matching part, the oil valve part, the oil outlet valve, the oil control valve fastening cap and the oil inlet metering valve are arranged on the pump body part; the eccentric driving mechanism drives the plunger and barrel assembly to reciprocate in the pump body part, high-pressure oil output by the oil delivery pump enters a high-pressure cavity formed by the oil valve part and the plunger and barrel assembly after passing through the oil inlet metering valve, and the high-pressure oil sequentially flows out of the oil outlet valve and the oil control valve fastening cap through the reciprocating motion of the plunger and barrel assembly. Also discloses a high-pressure common rail fuel injection system, which comprises the high-pressure in-line plunger pump.

Description

High-pressure in-line plunger pump and high-pressure common rail fuel injection system

Technical Field

The utility model relates to a plunger pump especially relates to a high pressure in-line plunger pump and high pressure common rail fuel injection system.

Background

With the rapid development of electronic control technology and the stricter emission regulations, the electronic control high-pressure common rail fuel injection system of the diesel engine becomes one of the development trends of modern diesel engine technology. The diesel engine electric control high-pressure common rail fuel injection system can accurately and flexibly control the fuel injection quantity, the fuel injection timing and the injection pressure of the diesel engine, and mainly depends on an adopted plunger pump. However, the plunger pump applied to the conventional electronic control high-pressure common rail fuel injection system has the problems of poor usability on fuel impurities, influence on the service life of a product, high processing difficulty, high cost, unsmooth exhaust and poor low-speed starting performance.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a high pressure in-line plunger pump and high pressure common rail fuel injection system to it is poor to fuel impurity's usability to solve correlation technique at least, influences product life, and the processing degree of difficulty is high, and is with high costs, and the exhaust is not smooth, the poor problem of low-speed startability.

In order to achieve the above object, the embodiment of the present invention adopts the following technical solutions:

in a first aspect, an embodiment of the present invention provides a high-pressure in-line plunger pump, including: the oil pump, the eccentric driving mechanism, the plunger matching part, the oil valve part, the oil outlet valve, the oil control valve fastening cap and the oil inlet metering valve are arranged on the pump body part; the eccentric driving mechanism drives the plunger and barrel assembly to reciprocate in the pump body part, high-pressure oil output by the oil delivery pump enters a high-pressure cavity formed by the oil valve part and the plunger and barrel assembly after passing through the oil inlet metering valve, and the high-pressure oil sequentially flows out of the oil outlet valve and the oil control valve fastening cap through the reciprocating motion of the plunger and barrel assembly.

Furthermore, the oil pump also comprises overflow valves which are connected in parallel at two ends of the oil transfer pump.

Furthermore, a first pressure balance hole is formed in the pump body part and used for guiding fuel leaked from the gap of the oil inlet metering valve to return to the oil inlet position.

Further, the eccentric drive mechanism includes: the plunger pump comprises a driving shaft bearing bush, a roller containing the bearing bush, an eccentric shaft and a flange bearing block, wherein one end of the eccentric shaft is supported on the pump body part through the driving shaft bearing bush, the other end of the eccentric shaft is supported on the flange bearing block through the other driving shaft bearing bush, the flange bearing block is fixed on the pump body part, the roller containing the bearing bush is fixed in the eccentric shaft, and the lower end of a plunger coupling part is abutted to the roller containing the bearing bush.

Further, the relative rotation of the eccentric shaft drives the fuel oil to enter the gaps between the eccentric shaft and the flange bearing, the eccentric shaft and the roller, and the eccentric shaft and the pump body component to form a fluid lubricating oil film.

Furthermore, be equipped with the oil blanket on the flange bearing frame, be equipped with second pressure balance hole on the flange bearing frame for the balance the pressure of oil blanket, be equipped with the oil blanket spacing groove on the flange bearing frame, pack into the oil blanket spacing groove through the snap ring in, prevent that the oil blanket from scurrying outward.

Furthermore, the oil valve part and the oil outlet valve are arranged in parallel, and are mutually attached, compressed and sealed through the oil valve part, the plunger matching part and the oil control valve tightening cap.

Furthermore, the oil inlet ends of the overflow valve, the oil valve component and the oil inlet metering valve are all provided with filtering structures.

Furthermore, an exhaust port is formed in the pump body component, and an exhaust screw is screwed on the exhaust port.

In a second aspect, embodiments of the present invention provide a high pressure common rail fuel injection system, comprising a high pressure in-line plunger pump according to the first aspect.

According to the technical scheme, the method has the following technical effects:

by adopting the design of split combined parts, the part which is difficult to process is converted into exposed processing from the processing of the inner cavity, so that the processing difficulty is greatly reduced.

The oil valve part is placed into the plunger matching part and then is mutually pressed and attached to the component part through the oil control valve tightening cap to form a closed oil inlet and return channel and a closed volume cavity, so that the sealing between parts is ensured while the simplicity of part processing is ensured, and the reliability of the high-pressure oil pump under the limit pressure is ensured.

The key parts are protected by adding the filtering structure, so that the early damage of the key parts caused by the fact that impurities are brought into fuel oil is prevented, the service life is prolonged, and the fault occurrence probability is reduced.

And a hydrodynamic lubrication mode is adopted to replace oil hole lubrication, so that an oil duct is simplified, and the processing difficulty is reduced.

The oil inlet and outlet of the high-pressure cavity are designed in a parallel oil way structure, and the arrangement space of the oil inlet and outlet way is saved, so that the structure is more compact.

The utility model discloses be equipped with exhaust structure, be favorable to the gaseous evacuation in the pipeline, guarantee low-speed startability.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is to be expressly understood that the drawings in the following description are illustrative of specific embodiments only and are not intended as a definition of the limits of the invention. It is obvious to a person skilled in the art that other embodiments and drawings can of course be obtained from the following embodiments of the invention and their drawings without inventive work.

Fig. 1 is a schematic diagram of an oil path structure of a high-pressure in-line plunger pump according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a high-pressure in-line plunger pump according to an embodiment of the present invention;

in the figure: the oil pump comprises a pump body component 1, an oil inlet bolt 2, an oil delivery pump 3, an end cover 4, a thrust washer 5, a driving shaft bearing bush 6, a roller 7 with a bearing bush, an eccentric shaft 8, a flange bearing block 9, an oil seal 10, a clamping ring 11, an oil return screw 12, an overflow valve 13, a plunger matching part 14, an oil inlet filter screen 15, an oil valve component 16, an oil outlet valve 17, an oil control valve fastening cap 18, an oil inlet metering valve 19, an exhaust screw 20, a hand pump 21, a filter 22 and an oil injector 23.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present application, the technical solution of the embodiment of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiment of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the specific embodiments described herein without making any inventive step, shall fall within the scope of the inventive concept.

Referring to fig. 1 and 2, the present embodiment provides a high-pressure inline plunger pump, mainly for a high-pressure common rail fuel injection system, comprising: the oil pump comprises a pump body part 1, and an oil delivery pump 3, an eccentric driving mechanism, a plunger matching part 14, an oil valve part 16, an oil outlet valve 17, an oil control valve fastening cap 18 and an oil inlet metering valve 19 which are arranged on the pump body part 1; the eccentric driving mechanism drives the plunger and barrel assembly 14 to reciprocate in the pump body part 1, high-pressure oil output by the oil delivery pump 3 enters a high-pressure cavity formed by the oil valve part 16 and the plunger and barrel assembly 14 after passing through the oil inlet metering valve 19, and the high-pressure oil sequentially flows out of the oil outlet valve 17 and the oil control valve fastening cap 18 through the reciprocating motion of the plunger and barrel assembly 14.

The fuel pump 3 sucks fuel from the fuel tank, the fuel pump 3 pumps the fuel into the plunger chamber through the fuel inlet metering valve 19 (the plunger and barrel assembly 14 is mounted in the plunger chamber), the plunger and barrel assembly 14 moves forward (suction stroke), and the fuel valve member 16 is closed when the plunger and barrel assembly 14 passes the bottom dead center. When the pressure reaches the supply pressure, the compressed fuel enters the high-pressure circulation (oil path). The plunger and barrel assembly 14 continues to supply fuel until, after top dead centre (delivery stroke) is reached, the pressure is reduced, causing the outlet valve 17 to close and the fuel pressure still in the plunger chamber to drop and the plunger and barrel assembly 14 moves downwardly again. As soon as the pressure in the plunger chamber drops below the supply pressure of the supply pump, the oil valve member 16 opens again and the oil pumping process starts again. The oil from the oil outlet valve 17 is sprayed through an oil sprayer 23.

In an embodiment of the present application, the oil valve member 16 mainly includes an oil inlet valve, a valve seat, and an oil inlet valve spring, the oil inlet valve is in clearance fit with the valve seat and sealed by a seat surface, and the oil inlet valve spring is sleeved on the oil inlet valve and fixed by a snap ring.

In an embodiment of the present application, the system further includes overflow valves 13, where the overflow valves 13 are connected in parallel to two ends of the oil transfer pump 3, and the overflow valves 12 play a role of pressure relief protection, so as to protect the high-pressure oil pump from leakage due to overpressure.

In this application embodiment, pump body part 1 on be equipped with first pressure balance hole for the guide the fuel that 19 gaps of oil feed metering valve were revealed gets back to oil feed department, furtherly, first pressure balance hole is realized through the mode of inlaying the dress throttle pin on pump body part 1, greatly reduced processing degree of difficulty, reduce cost.

In this application embodiment, the pump body adopts the design of wall thickness structure appearance such as constant on the basis of guaranteeing intensity, and oil feed, oil return, produce oil, plunger and oil feed metering valve, on the basis of guaranteeing enough installation space, the position is compact, easy to assemble.

In an embodiment of the present application, the eccentric driving mechanism includes: the pump comprises a drive shaft bearing bush 6, a roller 7 with a bearing bush, an eccentric shaft 8 and a flange bearing block 9, wherein one end of the eccentric shaft 8 is supported on the pump body part 1 through the drive shaft bearing bush 6, the other end of the eccentric shaft 8 is supported on the flange bearing block 9 through another drive shaft bearing bush 6, the flange bearing block 9 is fixed on the pump body part 1, the roller 7 with the bearing bush is fixed in the eccentric shaft 8, and the lower end of a plunger coupling 14 is abutted to the roller 7 with the bearing bush. When the eccentric shaft connecting device is used, the power of the eccentric shaft 8 comes from an engine, specifically, the engine gear is connected with the conical surface of the eccentric shaft 8 to drive the eccentric shaft 8 to rotate, and the eccentric shaft 8 drives the oil transfer pump to rotate through key connection.

Further, a hydrodynamic lubrication mode is adopted to replace oil hole lubrication, fuel oil is driven to enter gaps among the eccentric shaft 8, the flange bearing 9, the eccentric shaft 8, the roller 7, the eccentric shaft 8 and the pump body part 1 through relative rotation of the eccentric shaft 8 to form a fluid lubrication oil film, friction coefficient and abrasion are reduced, movement gaps are well protected and cooled, parts are prevented from being rusted, friction heat is reduced, and stable operation is guaranteed.

Furthermore, an oil seal 10 is arranged on the flange bearing seat 9, so that engine oil and diesel oil are effectively blocked, and the problem of mutual mixing of the engine oil and the diesel oil is prevented; a second pressure balance hole is formed in the flange bearing seat 9 and used for balancing the pressure of the oil seal 10 and preventing the oil seal from being leaked due to overhigh pressure; an oil seal limiting groove is formed in the flange bearing seat 9, and the oil seal limiting groove is filled with a clamping ring 11 to prevent the oil seal 10 from jumping outwards.

The first pressure balance hole and the second pressure balance hole are used for balancing the pressure of each cavity and are mainly arranged at different positions and in different modes, and the pump body is provided with a pin hole in an embedding mode, so that pressure can be maintained and balanced through a throttling hole; the flange bearing seat is realized by directly drilling a long and thin oil hole, and only pressure is balanced. And a hydrodynamic lubrication mode is adopted to replace oil hole lubrication, so that an oil duct is simplified, and the processing difficulty is reduced.

Furthermore, antifriction component thrust washers 5 are arranged between the eccentric shaft 8 and the pump body component 1 and between the eccentric shaft 8 and the flange bearing seat 9, so that relative abrasion among parts is reduced, and the service life of the product is prolonged.

In an embodiment of the present application, the inlets of the overflow valve 13, the inlet valve and the inlet metering valve 19 are all provided with an inlet filter screen 15, so as to filter the fuel entering the high-pressure oil pump for multiple times.

In an embodiment of the present application, the oil valve component 16 and the oil outlet valve 17 are disposed in parallel, so that the space for arranging the oil inlet and outlet paths can be saved, and the structure is more compact. The oil valve part 16, the plunger and barrel assembly 14 and the oil control valve fastening cap 18 are mutually abutted and pressed for sealing. The oil circuit design with the parallel structure is adopted, compared with the vertical direction design of other similar products, the product structure is more compact, the design of split combined parts is adopted, the part which is difficult to process is converted into exposed processing from the inner cavity processing, and the processing difficulty is greatly reduced. And meanwhile, the mode of tongue-and-groove sealing and plane sealing is used, so that the parts are attached without leakage. The oil inlet filter screen 15, the oil inlet valve 16, the oil outlet valve 17 and the oil control valve tightening cap 18 are respectively arranged in the plunger matching part 14 to form a whole and then are arranged in the pump body part 1.

In an embodiment of the application, the pump body component 1 is provided with an exhaust port, an exhaust screw 20 is screwed on the exhaust port, and the hand pump 21 is matched to discharge gas in a front oil path of the oil inlet metering valve 19 out of a pump cavity, so that the gas in a pipeline can be emptied conveniently, and the low-speed starting capability is ensured. In addition, a filter 22 can be installed to filter the oil before the oil is fed into the pump body member 1. The utility model discloses be equipped with exhaust screw 20, be favorable to the gaseous evacuation in the pipeline, guarantee low-speed startability.

In an embodiment of the present application, by controlling the matching length of the plunger matching part 14, the form and location tolerance of the matching surface, and the shape requirement, it is ensured that the high-pressure oil pump can meet higher sealing pressure, thereby meeting higher discharge requirement. The oil valve part is placed into the plunger matching part and then is mutually pressed and attached to the component part through the oil control valve tightening cap to form a closed oil inlet and return channel and a closed volume cavity, so that the sealing between parts is ensured while the simplicity of part processing is ensured, and the reliability of the high-pressure oil pump under the limit pressure is ensured.

In one embodiment of the application, fuel enters the pump body component 1 through the fuel inlet bolt 2, and the fuel inlet bolt 2 is in threaded connection with the pump body component 1; the fuel oil flows out of the pump body component 1 through the oil return screw 12 and returns to the oil tank, and the oil return screw 12 is connected with the pump body component through threads; the end cover 4 is fixed on the pump body component 1 through screws and is used for protecting the oil transfer pump 4.

The key oil circuit related to the steel ball seal and the movement of the matching parts is internally provided with a filtering structure, and the oil inlet ends of the oil inlet bolt part 2, the overflow valve 13, the oil valve part 16 and the oil inlet metering valve 19 are respectively provided with a filtering structure so as to prevent impurities from entering each key moving part and prevent early abrasion or clamping stagnation of key parts. The key parts are protected by adding the filtering structure, so that the early damage of the key parts caused by the fact that impurities are brought into fuel oil is prevented, the service life is prolonged, and the fault occurrence probability is reduced.

By adopting the design of split combined parts, the part which is difficult to process is converted into exposed processing from the processing of the inner cavity, so that the processing difficulty is greatly reduced.

The embodiment also provides a high-pressure common rail fuel injection system, which comprises the high-pressure in-line plunger pump and has all the effects of the high-pressure in-line plunger pump, and the details are not repeated herein.

The foregoing is merely a preferred embodiment of the present application and those skilled in the art will be able to understand and implement the present invention based on the foregoing. Various modifications to the above-described embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the particular embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A high pressure in-line plunger pump, comprising:

pump body component, and

the oil delivery pump, the eccentric driving mechanism, the plunger matching part, the oil valve part, the oil outlet valve, the oil control valve fastening cap and the oil inlet metering valve are arranged on the pump body part;

the eccentric driving mechanism drives the plunger and barrel assembly to reciprocate in the pump body part, high-pressure oil output by the oil delivery pump enters a high-pressure cavity formed by the oil valve part and the plunger and barrel assembly after passing through the oil inlet metering valve, and the high-pressure oil sequentially flows out of the oil outlet valve and the oil control valve fastening cap through the reciprocating motion of the plunger and barrel assembly.

2. A high pressure in-line plunger pump as claimed in claim 1, further comprising relief valves connected in parallel across the fuel delivery pump.

3. The high pressure in-line plunger pump of claim 1, wherein said pump body member defines a first pressure balancing hole for directing fuel leaking from said inlet metering valve gap back to the inlet.

4. A high pressure in-line plunger pump as claimed in claim 1, wherein the eccentric drive mechanism comprises: the plunger pump comprises a driving shaft bearing bush, a roller containing the bearing bush, an eccentric shaft and a flange bearing block, wherein one end of the eccentric shaft is supported on the pump body part through the driving shaft bearing bush, the other end of the eccentric shaft is supported on the flange bearing block through the other driving shaft bearing bush, the flange bearing block is fixed on the pump body part, the roller containing the bearing bush is fixed in the eccentric shaft, and the lower end of a plunger coupling part is abutted to the roller containing the bearing bush.

5. The high pressure in-line plunger pump of claim 4, wherein relative rotation of the eccentric shaft drives fuel into the gap between the eccentric shaft and the flange bearing, the eccentric shaft and the roller, and the eccentric shaft and the pump block member to form a fluid lubricating film.

6. The high-pressure in-line plunger pump as claimed in claim 4, wherein the flange bearing seat is provided with an oil seal, the flange bearing seat is provided with a second pressure balance hole for balancing the pressure of the oil seal, the flange bearing seat is provided with an oil seal limiting groove, and the flange bearing seat is arranged in the oil seal limiting groove through a clamping ring to prevent the oil seal from channeling outwards.

7. The high-pressure in-line plunger pump of claim 1, wherein the oil valve member and the oil outlet valve are arranged in parallel, and are pressed and sealed by the oil valve member, the plunger and barrel assembly and the oil control valve cap.

8. The high pressure in-line plunger pump of claim 2, wherein the oil inlet ends of the spill valve, the oil valve member and the oil inlet metering valve are provided with a filter structure.

9. The high pressure in-line plunger pump of claim 1, wherein the pump body member has a vent port with a vent screw threaded thereon.

10. A high pressure common rail fuel injection system comprising a high pressure in-line plunger pump as claimed in any one of claims 1 to 9.

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