Valve assembly for fuel pump and fuel pump

Abstract

The utility model relates to the field of fuel pumps, in particular to a valve assembly for a fuel pump, the valve assembly is arranged on the fuel pump and used for controlling the fuel pump to convey fuel to a fuel consumption device, and the valve assembly comprises a valve shell; a valve holder disposed on the valve housing and configured to be adapted to hold a valve element; a seal disposed in the annular groove of the valve holder and configured to be adapted to seal an interior of the valve housing with respect to an ambient fluid in a state in which the valve holder is disposed on the valve housing; wherein an anti-corrosion layer is at least arranged on the surface of the annular groove. The utility model further relates to the fuel pump comprising the valve assembly. By means of at least one embodiment of the fuel pump and the valve assembly, it can be guaranteed that stress corrosion caused by the influence of the external environment cannot occur in the annular groove, used for the sealing piece, of the valve maintaining piece, and therefore the operation reliability of the fuel pump and the valve assembly is guaranteed.

Description

Technical Field

[0001] The utility model relates to the field of fuel pumps, in particular to a valve assembly for a fuel pump. In addition, the utility model relates to a fuel pump with the valve assembly. Background Art

[0002] A delivery valve is usually arranged in a fuel pump, for example a plunger pump, which serves to deliver the liquid fuel compressed by the plunger pump in a controlled manner to a fuel consumer, for example to an internal combustion engine.

[0003] The delivery valve includes a valve holder, which is used to hold the valve element therein and is connected to the valve housing, for example, by screwing. In the prior art, the valve holder is constructed as a steel cylinder and an annular groove for an O-ring is machined on the outer circumference of the cylinder by a known processing technology, such as turning. As a result, when the valve holder is connected to the valve housing together with the valve element by screwing, the interior of the valve housing or the interior of the fuel pump can be sealed from the external environment fluid by the sealing ring located in the annular groove between the valve housing and the valve holder. Therefore, dirt or fluids in the external environment, such as water, etc., cannot penetrate into the delivery valve and the fuel pump.

[0004] However, due to the material of the valve holder and the processing technology of the annular groove, a large stress is generated at the annular groove. If the annular groove is exposed to a corrosive environment, for example, water intrudes into the annular groove, stress corrosion cracking (SCC) may occur at the annular groove under the combined action of stress, corrosive media and alternating loads of the fuel pump, which leads to damage to the valve holder and failure of the delivery valve and thus damage to the fuel pump.

[0005] Therefore, in view of the many deficiencies in the prior art, there is still a need for improvement of the above technical solutions. Utility Model Content

[0006] In order to overcome one of the above disadvantages and / or possible other disadvantages of the prior art not mentioned herein, the purpose of the present invention is to provide an improved valve assembly for a fuel pump and a corresponding improved fuel pump.

[0007] According to a first aspect of the utility model, a valve assembly for a fuel pump is provided, wherein the valve assembly is arranged on the fuel pump and is used to control the fuel delivery of the fuel pump to a fuel consuming device, and the valve assembly comprises:

[0008] valve housing;

[0009] a valve retainer disposed on the valve housing and configured to retain a valve element;

[0010] a sealing member arranged in the annular groove of the valve holder and configured to seal the interior of the valve housing from the external environment in a state where the valve holder is arranged on the valve housing;

[0011] Wherein, an anti-corrosion layer is provided at least on the surface of the annular groove.

[0012] The basic idea of ​​the utility model is that by coating at least the annular groove of the valve holder with an anti-corrosion layer, the risk of stress corrosion cracking of the annular groove due to exposure to a corrosive environment, such as exposure to water, can be particularly simply and effectively avoided. In addition, the valve assembly or the valve holder can also be manufactured in a particularly cost-effective manner through this solution.

[0013] The advantageous configuration of the technical solution of the utility model can be obtained from the following optional embodiments.

[0014] According to an optional embodiment of the valve assembly of the utility model, the valve retainer is configured as a cylinder and includes a first section, a second section, and an intermediate section located between the first section and the second section and connected to the first section and the second section respectively along the direction from the first end to the second end of the valve retainer, and the annular groove is configured on the second section in the circumferential direction of the valve retainer. This embodiment can realize a three-section structure of the valve retainer and realize different functions of each section.

[0015] According to an optional embodiment of the valve assembly of the utility model, a shaft shoulder is configured on the second section to connect with the middle section, and the annular groove is configured to connect with the shaft shoulder. This embodiment has a simple structure and is easy to process.

[0016] According to an optional embodiment of the valve assembly of the present utility model, a first external thread is configured on the first section, and the first external thread extends to the first end.

[0017] According to an optional embodiment of the valve assembly of the utility model, a second external thread is configured on the second section, the second external thread is connected with the annular groove and extends to the second end, wherein an opening is configured on the valve housing, and an internal thread corresponding to the second external thread is configured on the inner wall of the opening. This embodiment realizes a tight connection between the valve retainer and the valve housing by means of threaded fit.

[0018] According to an optional embodiment of the valve assembly of the utility model, the middle section is configured as a tool attachment portion for an assembly tool, and the valve holder is assembled on the valve housing by means of the tool attachment portion. This embodiment facilitates the assembly of the valve holder.

[0019] According to an optional embodiment of the valve assembly of the utility model, an anti-corrosion layer is additionally provided on the surface of the shaft shoulder. This embodiment facilitates the coating of the anti-corrosion layer.

[0020] According to an optional embodiment of the valve assembly of the present utility model, a stepped through passage for arranging the valve element is configured in the valve retainer along a direction from the first end to the second end.

[0021] According to an optional embodiment of the valve assembly of the utility model, the anti-corrosion layer is a coating sprayed by metal. This embodiment ensures reliable corrosion resistance of the coating, especially prevents rust.

[0022] According to an optional embodiment of the valve assembly of the utility model, the anti-corrosion layer is a zinc-aluminum coating. This embodiment is particularly effective in protecting the annular groove from corrosion, especially rust.

[0023] According to an optional embodiment of the valve assembly of the utility model, the sealing element is a rubber O-ring. This embodiment has a simple structure and is cost-effective.

[0024] According to an optional embodiment of the valve assembly of the present invention, the valve retainer is a steel valve retainer.

[0025] According to a second aspect of the utility model, a fuel pump is provided, wherein the fuel pump comprises a valve assembly according to one of the above embodiments.

[0026] According to an optional embodiment of the fuel pump of the present invention, the fuel pump is configured to deliver fuel to a vehicle engine.

[0027] According to an optional embodiment of the fuel pump of the present invention, the fuel pump is configured as a diesel pump.

[0028] More features of the utility model become apparent from the claims, the drawings and the description of the drawings. The features and feature combinations mentioned in the above description and the features and feature combinations mentioned in the following description of the drawings and / or shown only in the drawings can be used not only in the corresponding specified combinations, but also in other combinations without departing from the scope of the utility model. Therefore, the following contents are also regarded as being covered and disclosed by the utility model: these contents are not explicitly shown in the drawings and are not explicitly explained, but are derived from a combination of features separated from the explained contents and are generated by these combinations. The following contents and feature combinations are also regarded as being disclosed: they do not have all the features of the originally drafted independent claims. In addition, the following contents and feature combinations are regarded as being particularly disclosed by the above contents: they exceed or deviate from the feature combinations defined in the reference relationship of the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further optional details and features of the invention emerge from the following description of preferred exemplary embodiments which are schematically illustrated in the drawings.

[0030] Figure 1 A perspective view of an embodiment of a fuel pump according to the present utility model is shown;

[0031] Figure 2 A partial cross-sectional view of an embodiment of a valve assembly according to the present utility model is shown;

[0032] Figure 3 shows a front view of a valve retainer of a valve assembly according to the prior art;

[0033] Figure 4 A front view showing an embodiment of a valve retainer of a valve assembly according to the present invention; and

[0034] Figure 5 Shows Figure 4 A partial enlarged cross-sectional view of the valve retainer in FIG.

[0035] Reference numerals list

[0036] 1 Fuel Pump

[0037] 2 valve assembly

[0038] 3 valve housing

[0039] 4 Valve retainer

[0040] 5 Seals

[0041] 6 Anti-corrosion layer

[0042] 31 Opening

[0043] 41 First End

[0044] 42 The Second End

[0045] 43 First Segment

[0046] 44 Middle section

[0047] 45 Second Section

[0048] 46 Annular groove

[0049] 47 Shoulder

[0050] 48 Through Passage

[0051] 311 Internal thread

[0052] 431 First external thread

[0053] 451 Second external thread

[0054] 461 Chamfer. DETAILED DESCRIPTION

[0055] In order to make the technical problems, technical solutions and beneficial technical effects to be solved by the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and multiple exemplary embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the scope of protection of the present invention.

[0056] In the absence of conflict, the features in the embodiments of the present invention can be combined with each other. In different drawings, the same components are represented by the same reference numerals, and other components are omitted for the sake of brevity, but this does not mean that the technical solution of the present invention cannot include other components. It should be understood that the size, proportional relationship and number of components in the drawings are not intended to limit the present invention.

[0057] Figure 1 A perspective view of a fuel pump 1 according to an embodiment of the present invention is shown.

[0058] The fuel pump 1 is used to deliver fuel to a fuel consumption device. In this embodiment, the fuel pump 1 is used for a vehicle and delivers liquid fuel to the engine of the vehicle. Exemplarily, the fuel pump 1 can compress diesel to high pressure and deliver it to the high-pressure common rail system of the diesel engine. Therefore, the fuel pump 1 is configured as a diesel pump.

[0059] The fuel pump 1 is constructed as a plunger pump as known in the prior art, and the liquid fuel is sucked and compressed by the reciprocating motion of the plunger in the cylindrical cylinder. Since the fuel pump 1 as a plunger pump is known in the prior art, the description of each specific component of the fuel pump 1 and the corresponding working method is omitted here.

[0060] In order to control the delivery of high-pressure fuel in a controlled manner, a valve assembly 2 is arranged on the fuel pump 1. Figure 1 As shown schematically, the valve assembly 2 is arranged at the upper part of the fuel pump 1 and two valve assemblies 2 are provided exemplarily, and each valve assembly 2 corresponds to a fuel delivery passage.

[0061] Figure 2 A partial cross-sectional view of an embodiment of a valve assembly 2 according to the utility model is shown. According to this embodiment, see also Figure 1 The valve assembly 2 includes a valve housing 3. The valve housing 3 may be made of a metal material and is fastened to the fuel pump 1 by bolts.

[0062] In addition, the valve assembly 2 further includes a valve retainer 4, which is arranged on the valve housing 3 and is configured to be suitable for retaining a valve element (not shown in detail). An opening portion 31 is configured at the upper portion of the valve housing 3. The opening portion 31 is in fluid communication with the fuel pump 1. The valve retainer 4 is made of steel or alloy steel and has high strength.

[0063] According to this embodiment, the valve holder 4 is configured as a cylinder, for example a circular cylinder. The valve holder 4 is configured in multiple sections and is manufactured by machine tool processing, for example turning. Figure 2 The drawing plane is the upper end) to the second end 42 (at Figure 2 The first section 43, the second section 45, and the middle section 44 located between the first section 43 and the second section 45 and connected to the first section 43 and the second section 45, respectively, are provided in the direction of the drawing plane (the lower end). In other words, the first section 43 and the second section 45 are respectively machined from the middle section 44, for example, by turning. Therefore, a shoulder 47 is constructed in the second section 45 to connect to the middle section 44. Figure 2 As shown in the example, the circumferential size of the first segment 43 is smaller than the circumferential size of the second segment 45 , and the circumferential size of the first segment 43 and the circumferential size of the second segment 45 are both smaller than the circumferential size of the middle segment 44 .

[0064] A stepped through-channel 48 for arranging a valve element is formed in the valve holder 4 in the direction from the first end 41 to the second end 42. The stepped through-channel 48 is thus in fluid communication with the interior of the valve housing 3 and with the fuel pump 1 in a defined manner.

[0065] In the second section 45, an annular groove 46 is formed in the circumferential direction in connection with the shaft shoulder 47, that is, the annular groove 46 is formed on the outer periphery of the second section 45. The annular groove 46 is used to accommodate the seal 5 of the valve assembly 2. In this embodiment, the seal 5 is formed as an O-ring made of rubber.

[0066] When the valve holder 4 is arranged on the valve housing 3, the seal 5 is pressed between the annular groove 46 and the inner wall of the opening 31 in the radial direction and is in sealing contact with the inner wall and the surface of the annular groove 46. As a result, the interior of the valve housing 3 or the interior of the fuel pump 1 is sealed from the external environment. Therefore, pollutants or corrosive substances such as liquids or particles from the external environment of the valve housing 3 will not penetrate into the interior of the fuel pump 1 through the valve holder 4.

[0067] In order to facilitate assembly, a first external thread 431 is configured on the first section 43. According to this embodiment, the first external thread 431 extends from the junction of the first section 43 and the middle section 44 to the first end 41. With the help of the first external thread 431, the first end 41 can be fastened to a delivery pipe of a high-pressure common rail system leading to a diesel engine, for example. A second external thread 451 is configured on the second section 45, and the second external thread 451 is connected to the annular groove 46 and extends to the second end 42. Correspondingly, an internal thread 311 corresponding to the second external thread 451 is configured on the inner wall of the opening 31 of the valve housing 3. As a result, the valve holder 4 can be fastened in the opening 31 of the valve housing 3 by screw connection in a particularly simple manner.

[0068] Further, the middle section 44 is configured as a tool attachment portion for an assembly tool, by means of which the valve holder 4 is assembled on the valve housing 3. In this embodiment, the tool attachment portion is configured to have an outer hexagonal shape, see also the subsequent Figure 3 or 4. Therefore, the valve holder 4 can be easily screwed into the opening portion 31 of the valve housing 3 by a hexagonal wrench.

[0069] Figure 3 A front view of a valve holder 4 of a valve assembly 2 according to the prior art is shown. The valve holder 4 is machined in a similar manner, for example by turning and then subjected to a corresponding heat treatment and then fine machining.

[0070] However, due to the stress generated on the valve retainer 4 during the processing, especially the chamfer 461 of the annular groove 46 may generate a large stress. When the valve retainer 4 is installed on the valve housing 3, the seal 5 seals the inside of the valve housing 3 from the external environment. However, the upper part of the annular groove 46, i.e., the Figure 3 The portion at the chamfer 461 in the plane of the accompanying drawing is not fluid-tight with respect to the external environment. In other words, this portion is exposed to the external environment. If the external environment is humid or, for example, the user flushes and cleans the fuel pump 1 with water, water or moisture may invade this portion. Due to the combined effects of water and the greater stress, especially at the above-mentioned portion, and in some cases, the alternating load factors of the fuel pump 1 during operation, stress corrosion cracking may occur at this portion. This may not only cause corrosion and rusting at this portion, but more seriously, it may cause the valve retainer 4 to break, the seal 5 to be damaged and fail, and further cause damage to the entire fuel pump 1. Therefore, it is urgent to solve the failure risk of the valve retainer 4 in the prior art due to stress corrosion cracking.

[0071] Based on the above problems existing in the prior art, Figure 4 and Figure 5 , combined Figure 1 and 2 And with Figure 3 The embodiments of the present utility model are described in detail in contrast.

[0072] Figure 4 A front view of an embodiment of a valve holder 4 of a valve assembly 2 according to the present invention is shown. Figure 5 Shows Figure 4 A partially enlarged sectional view of the valve retainer 4 in FIG.

[0073] If already Figure 2 As explained in detail in FIG. 2 , an annular groove 46 is formed in the second section 45 of the valve holder 4 in the circumferential direction adjoining the shoulder 48. The annular groove 46 serves to accommodate the seal 5 of the valve assembly 2.

[0074] Compared with the prior art, in order to prevent stress corrosion cracking from occurring on the upper portion of the annular groove 46, according to one embodiment, an anti-corrosion layer 6 is provided at least on the surface of the annular groove 46. The anti-corrosion layer 6 is a coating sprayed by metal. In the present utility model, the metal coating includes a coating composed of a single metal or a composite metal layer composed of multiple metals.

[0075] According to this exemplary embodiment, the anti-corrosion layer 6 is a zinc-aluminum coating, which has correspondingly good corrosion protection.

[0076] Alternatively, in another embodiment, the anti-corrosion layer 6 may be composed of a non-metallic coating, such as a nano coating, etc., which can at least protect the annular groove 46 with relatively large stress from the risk of stress corrosion cracking.

[0077] According to this embodiment, even if stress still exists at the annular groove 6, stress corrosion cracking will not occur in the annular groove 46 due to the coating of the anti-corrosion layer 6. This significantly improves the corrosion resistance and service life of the valve holder 4.

[0078] according to Figure 4 and Figure 5 In the illustrated embodiment, the anti-corrosion layer 6 is also coated on the surface of the shaft shoulder 47 of the valve holder 4. That is, the anti-corrosion layer 6 is coated from the middle section 44 or the tool attachment portion of the valve holder 4 toward the second section 45 until the lower edge of the annular groove 6 or until above the second external thread 451. In this way, not only can the coating process be simplified, but also the shaft shoulder 47, which is also exposed to the external environment and has relatively small stress, can be additionally protected from the risk of stress corrosion cracking, thereby further improving the service reliability and life of the valve holder 4.

[0079] Of course, it is also conceivable to coat the surfaces of the annular groove 6 and the shaft shoulder 47 with more than one anti-corrosion layer to avoid the risk of corrosion to the greatest extent.

[0080] In this specification, unless otherwise clearly specified and limited, the terms "arrangement", "connection" and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, or a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate, or a connection between the two elements. The expressions "first", "second", etc. are only used for descriptive purposes and should not be understood as indicating or implying relative importance, nor should they be understood as implicitly indicating the number of technical features indicated. Features defined as "first" or "second" may explicitly or implicitly indicate that at least one of the features is included. For those of ordinary skill in the art, the meaning of the above terms in the utility model can be understood according to the circumstances.

Claims

1. A valve assembly for a fuel pump, wherein the valve assembly (2) is arranged on the fuel pump (1) and is used to control the fuel delivery of the fuel pump (1) to a fuel consuming device, characterized in that: The valve assembly (2) comprises: Valve housing(3); a valve retainer (4) arranged on the valve housing (3) and configured to retain a valve element; a sealing member (5) arranged in an annular groove (46) of the valve retainer (4) and configured to seal the interior of the valve housing (3) from the external environment fluid when the valve retainer (4) is arranged on the valve housing (3); An anti-corrosion layer (6) is provided at least on the surface of the annular groove (46).

2. The valve assembly according to claim 1, characterized in that The valve retaining member (4) is constructed as a cylinder and includes a first section (43), a second section (45) and an intermediate section (44) located between the first section (43) and the second section (45) and connected to the first section (43) and the second section (45) respectively along the direction from the first end (41) to the second end (42) of the valve retaining member (4), and the annular groove (46) is constructed on the second section (45) in the circumferential direction of the valve retaining member (4).

3. The valve assembly according to claim 2, characterized in that A shoulder (47) is formed on the second section (45) so as to adjoin the central section (44), and the annular groove (46) is formed so as to adjoin the shoulder (47).

4. The valve assembly according to claim 2 or 3, characterized in that: A first external thread (431) is formed on the first section (43), and the first external thread (431) extends to the first end (41); and / or A second external thread (451) is formed on the second section (45), the second external thread (451) is connected to the annular groove (46) and extends to the second end (42), wherein an opening (31) is formed on the valve housing (3), and an internal thread (311) corresponding to the second external thread (451) is formed on the inner wall of the opening (31); and / or The intermediate section (44) is designed as a tool attachment for a mounting tool, by means of which the valve holder (4) is mounted on the valve housing (3).

5. The valve assembly according to claim 3, characterized in that An anti-corrosion layer (6) is additionally provided on the surface of the shaft shoulder (47).

6. The valve assembly according to claim 2 or 3, characterized in that: A stepped through-channel (48) for arranging the valve element is formed in the valve holder (4) in the direction from the first end (41) to the second end (42).

7. The valve assembly according to any one of claims 1 to 3 and 5, characterized in that The anti-corrosion layer (6) is a coating sprayed by metal.

8. The valve assembly according to claim 7, characterized in that The anti-corrosion layer (6) is a zinc-aluminum coating; and / or The sealing element (5) is a rubber O-ring; and / or The valve retainer (4) is a steel valve retainer.

9. A fuel pump, characterized in that: The fuel pump (1) comprises a valve assembly (2) according to any one of claims 1 to 8.

10. The fuel pump according to claim 9, characterized in that The fuel pump (1) is configured to deliver fuel to a vehicle engine; and / or The fuel pump (1) is designed as a diesel pump.

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