Timing positioning structure and fuel injection pump

Abstract

The utility model relates to a timing positioning structure which comprises a fuel injection pump shell, a fuel injection pump cam shaft, a mounting seat, a bayonet lock and an end cover. A clamping groove is formed in the fuel injection pump camshaft; the mounting seat is mounted on a fuel injection pump shell, a step through hole is formed in the mounting seat, and the step through hole comprises a small-aperture section and a large-aperture section; the end cover is connected to the outer side of the mounting base, and the end cover and the large-aperture section define a containing space; the clamping pin comprises a pin head section, a first pin body section, an outer convex ring and a second pin body section, when the clamping pin is located at the first mounting position, the first pin body section is matched with the small-aperture section, the pin head section is clamped into the clamping groove, and the second pin body section is contained in the containing space; when the clamping pin is located at the second installation position, the second pin body section is matched with the small-aperture section, and the pin head section and the first pin body section are contained in the containing space. The utility model further provides the fuel injection pump. The mounting precision and the maintenance quality of the fuel injection pump can be guaranteed, and the maintenance difficulty of the fuel injection pump can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of internal combustion engines, and particularly relates to a timing positioning structure and a fuel injection pump. Background Art

[0002] In order to ensure the working performance of the fuel injection pump, during the assembly process of the fuel injection pump, it is necessary to ensure the timing installation position of the camshaft. In the prior art, usually a through hole is opened on the pump body, and during the assembly process of the fuel injection pump, a timing positioning pin is used to cooperate with the positioning hole on the camshaft to limit the circumferential position of the camshaft. After the fuel injection pump is assembled, the timing positioning pin is taken out and the through hole on the pump body is closed by a plugging member, so as to ensure the timing installation position of the camshaft.

[0003] The following technical problems exist in using the above method to ensure the timing installation position of the camshaft:

[0004] During the maintenance process of the fuel injection pump, it is necessary to open the through hole and use a timing positioning pin to limit the circumferential position of the camshaft. In some maintenance locations, the corresponding timing positioning pin may not be configured, resulting in problems of high maintenance difficulty and difficult to guarantee the maintenance quality;

[0005] In the assembly workshop, the timing positioning pin is reused. After the timing positioning pin is worn, the accuracy of the timing installation position of the camshaft is likely to be too low, which will have a negative impact on the working performance of the fuel injection pump. Summary of the Utility Model

[0006] The purpose of the utility model is to provide a timing positioning structure and a fuel injection pump to alleviate or eliminate at least one of the above technical problems.

[0007] A timing positioning structure according to the utility model includes a fuel injection pump housing, a fuel injection pump camshaft, a mounting seat, a retaining pin and an end cover;

[0008] A slot is provided on the circumferential side of the fuel injection pump camshaft, and an installation through hole is provided on the fuel injection pump housing;

[0009] The mounting seat is fixedly installed at the installation through hole. A stepped through hole coaxial with the installation through hole is provided in the mounting seat. The stepped through hole includes a small-diameter section, a stepped surface and a large-diameter section arranged in sequence from the inside to the outside;

[0010] The end cover is detachably and fixedly connected to the outside of the mounting seat. The end cover closes the outer port of the stepped through hole. An accommodation space is formed between the end cover and the large-diameter section;

[0011] The clamping pin includes a pin head section, a first pin body section, an outwardly protruding ring, and a second pin body section that are connected in sequence. The clamping pin has a first installation position and a second installation position. When the clamping pin is in the first installation position, the outwardly protruding ring is supported on the step surface, the first pin body section cooperates with the small-diameter section, the pin head section extends into the inner cavity of the fuel injection pump housing and is snapped into the card slot to define the circumferential position of the fuel injection pump camshaft, and the second pin body section is accommodated in the accommodation space; when the clamping pin is in the second installation position, the outwardly protruding ring is supported on the step surface, the second pin body section cooperates with the small-diameter section, the pin head section and the first pin body section are accommodated in the accommodation space, and the clamping pin and the fuel injection pump camshaft are separated from each other.

[0012] Optionally, an outer annular groove is provided on the second pin body section, and a sealing ring is installed in the outer annular groove. When the clamping pin is in the second installation position, the sealing ring forms a seal between the second pin body section and the small-diameter section.

[0013] Optionally, a threaded hole is provided on the end face of the second pin body section facing away from the outwardly protruding ring.

[0014] Optionally, an internal thread is provided in the large-diameter section, and an external thread is provided on the end cover. The internal thread cooperates with the external thread to detachably and fixedly connect the end cover to the outside of the mounting seat.

[0015] Optionally, a blind hole with an opening facing inward is provided in the end cover. The inner diameter of the blind hole is smaller than the outer diameter of the outwardly protruding ring, the inner diameter of the blind hole is larger than the outer diameter of the first pin body section and the outer diameter of the pin head section, and the inner diameter of the blind hole is larger than the outer diameter of the second pin body section.

[0016] Optionally, a sealing gasket is clamped between the end cover and the mounting seat, and the sealing gasket forms a seal between the end cover and the mounting seat.

[0017] Optionally, the mounting seat includes a mating portion that mates with the mounting through hole and an ear portion that protrudes radially from the mating portion. The ear portion is fixedly connected to the fuel injection pump housing by bolts.

[0018] Optionally, a sealing member is provided between the ear portion and the fuel injection pump housing, and the sealing member forms a seal between the mounting seat and the fuel injection pump housing.

[0019] The present utility model also proposes a fuel injection pump, including the timing positioning structure described in any one of the above.

[0020] The present utility model helps to ensure the installation accuracy and maintenance quality of the fuel injection pump, and also helps to reduce the maintenance difficulty of the fuel injection pump. Brief Description of the Drawings

[0021] Figure 1 One of the cross-sectional views of the timing positioning structure described in some embodiments;

[0022] Figure 2 Another cross-sectional view of the timing positioning structure described in some embodiments;

[0023] Figure 3 Schematic structural diagram of the mounting seat, the retaining pin and the end cover described in some embodiments;

[0024] Figure 4 Schematic structural diagram of the fuel injection pump described in some embodiments.

[0025] Wherein: 1 - fuel injection pump housing; 2 - fuel injection pump camshaft; 3 - mounting seat; 4 - retaining pin; 5 - end cover; 6 - gasket; 7 - bolt; 8 - electronic unit pump;

[0026] 101 - mounting through hole; 201 - card slot; 301 - connecting portion; 302 - ear portion; 303 - mating portion; 304 - large-diameter section; 305 - small-diameter section; 306 - connecting hole;

[0027] 401 - pin head section; 402 - first pin body section; 403 - outer convex ring; 404 - second pin body section; 405 - reduced-diameter section; 406 - threaded hole; 407 - outer annular groove; 408 - first guiding portion; 409 - second guiding portion; 410 - third guiding portion;

[0028] 501 - body; 502 - external thread; 503 - blind hole. Detailed Embodiments

[0029] The following will describe the embodiments of the present invention with reference to the drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the protection scope of the present invention.

[0030] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape and size of the components in actual implementation. The type, quantity and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0031] As shown Figures 1 to 3 A timing positioning structure, comprising a fuel injection pump housing 1, a fuel injection pump camshaft 2, a mounting seat 3, a retaining pin 4 and an end cover 5; a slot 201 is provided on the circumferential side of the fuel injection pump camshaft 2, and a mounting through hole 101 is provided on the fuel injection pump housing 1; the mounting seat 3 is fixedly installed at the mounting through hole 101, and a stepped through hole coaxial with the mounting through hole 101 is provided in the mounting seat 3. The stepped through hole includes a small-diameter section 305, a stepped surface and a large-diameter section 304 arranged in sequence from the inside to the outside. The diameter of the large-diameter section 304 is larger than that of the small-diameter section 305; the end cover 5 is detachably and fixedly connected to the outside of the mounting seat 3, the end cover 5 closes the outer port of the stepped through hole, and the end cover 5 and the large-diameter section 304 enclose a receiving space; the retaining pin 4 includes a pin head section 401, a first pin body section 402, an outer convex ring 403 and a second pin body section 404 connected in sequence. The retaining pin 4 has a first installation position and a second installation position. When the retaining pin 4 is in the first installation position, the outer convex ring 403 is supported on the stepped surface, the first pin body section 402 cooperates with the small-diameter section 305, and the pin head section 401 extends into the inner cavity of the fuel injection pump housing 1 and is stuck into the slot 201 to limit the circumferential position of the fuel injection pump camshaft 2, and the second pin body section 404 is received in the receiving space; when the retaining pin 4 is in the second installation position, the outer convex ring 403 is supported on the stepped surface, the second pin body section 404 cooperates with the small-diameter section 305, and the pin head section 401 and the first pin body section 402 are received in the receiving space, and the retaining pin 4 and the fuel injection pump camshaft 2 are separated from each other.

[0032] Adopting the above technical solution, during the assembly process of the fuel injection pump, the mounting seat 3 is fixedly installed on the fuel injection pump housing 1, and then the retaining pin 4 can be installed in the first installation position. The fuel injection pump camshaft 2 is positioned at the timing installation position by using the retaining pin 4. Each fuel injection pump is equipped with a retaining pin 4, which can ensure the positioning accuracy of the fuel injection pump cam, and thus ensure the timing installation position accuracy of the camshaft.

[0033] In the above technical solution, after the fuel injection pump is assembled and before the fuel injection pump is used, the end cover 5 can be removed, the retaining pin 4 can be taken out and the position of the retaining pin 4 can be reversed, the retaining pin 4 is installed in the second installation position, and the end cover 5 is installed on the mounting seat 3, then the positioning of the retaining pin 4 on the fuel injection pump camshaft 2 can be released, so that the fuel injection pump camshaft 2 can rotate. During subsequent maintenance, the end cover 5 can be removed to position the fuel injection pump camshaft 2 at the timing installation position by using the retaining pin 4, which can reduce the maintenance difficulty of the fuel injection pump and ensure the maintenance quality of the fuel injection pump. Moreover, during the transportation of the fuel injection pump before the fuel injection pump is used, the retaining pin 4 can also be used to maintain the circumferential position of the fuel injection pump camshaft 2.

[0034] In some embodiments, an outer annular groove 407 is provided on the second pin body section 404, and a sealing ring is installed in the outer annular groove 407. When the locking pin 4 is in the second installation position, the sealing ring forms a seal between the second pin body section 404 and the small-diameter section 305. With the above technical solution, during the use of the fuel injection pump, the sealing ring can be used to prevent oil leakage at the timing positioning structure. Specifically, the sealing ring can be an O-ring.

[0035] Further, in order to reduce the assembly difficulty of the second pin body section 404, the end of the second pin body section 404 can be set as a reduced-diameter section 405, and the outer annular groove 407 is provided on the reduced-diameter section 405. Setting the reduced-diameter section 405 can reduce the difficulty of inserting the second pin body section 404 into the small-diameter section 305, and can also reduce the difficulty of installing the sealing ring onto the outer annular groove 407.

[0036] In some embodiments, a threaded hole 406 is provided on the end face of the second pin body section 404 at the end facing away from the outer convex ring 403. With the above technical solution, since the length of the second pin body section 404 is short, by providing the threaded hole 406 on the second pin body section 404, when the locking pin 4 is installed in the first installation position, the locking pin 4 can be pulled out from the mounting seat 3 by using a threaded part that mates with the threaded hole 406, reducing the disassembly difficulty of the locking pin 4. Similarly, the threaded part can also be used to assist in installing the locking pin 4, thereby reducing the installation difficulty of the locking pin 4.

[0037] In some embodiments, an internal thread is provided in the large-diameter section 304, and an external thread 502 is provided on the end cover 5. The internal thread cooperates with the external thread 502 to detachably and fixedly connect the end cover 5 to the outside of the mounting seat 3. With the above technical solution, the end cover 5 has the characteristic of being easy to assemble. Specifically, the outer part of the end cover 5 can be set as a multi-prismatic shape, and then a wrench can be used to disassemble and assemble the end cover 5.

[0038] In some embodiments, a blind hole 503 with an opening facing inward is provided in the end cover 5. The inner diameter of the blind hole 503 is smaller than the outer diameter of the outer convex ring 403, the inner diameter of the blind hole 503 is larger than the outer diameters of the first pin body section 402 and the pin head section 401, and the inner diameter of the blind hole 503 is larger than the outer diameter of the second pin body section 404. With the above technical solution, the blind hole 503 is used to form a receiving space, and the first pin body section 402 and the pin head section 401 are inserted and received in the blind hole 503, and the second pin body section 404 can be inserted and received in the blind hole 503. Further, since the inner diameter of the blind hole 503 is smaller than the outer diameter of the outer convex ring 403, the inner end face of the end cover 5 can limit the outer convex ring 403, limiting the outer convex ring 403 between the step surface and the inner end face of the end cover 5, thereby limiting the axial movement range of the locking pin 4, which is beneficial to maintaining the cooperation between the pin head section 401 and the card slot 201, and is beneficial to maintaining the sealing performance of the sealing ring.

[0039] In some embodiments, a gasket 6 is clamped between the end cover 5 and the mounting base 3, and the gasket 6 forms a seal between the end cover 5 and the mounting base 3. With the above technical solution, the gasket 6 can form a layer of seal, and the sealing ring can also form a layer of seal. By adopting double-layer sealing, the sealing performance of the timing positioning structure can be ensured. In specific implementation, the end cover 5 includes a body 501 with a closed outer side, the body 501 encloses a blind hole 503, an external thread 502 is provided at the inner part of the end cover 5, a clamping surface is provided on the end cover 5, and the gasket 6 is clamped between the clamping surface and the outer end surface of the mounting base 3.

[0040] In some embodiments, the mounting base 3 includes a mating portion 303 that mates with the mounting through-hole 101, an ear portion 302 that protrudes radially from the mating portion 303, and a connecting portion 301 connected to the outside of the mating portion 303. The ear portion 302 is fixedly connected to the fuel injection pump housing 1 through a bolt 7, and the end cover 5 is connected to the connecting portion 301. In specific implementation, a connecting hole 306 is provided on the ear portion 302, and the bolt 7 passes through the connecting hole 306 and is connected to the threaded hole on the fuel injection pump housing 1 to fixedly connect the mounting base 3 to the fuel injection pump housing 1.

[0041] The fuel injection pump housing is usually made by casting. If the mounting through-hole of the fuel injection pump housing is directly set as a threaded hole to connect the plug, it is necessary to disassemble and assemble the plug every time the camshaft timing is positioned, which is likely to cause damage to the threaded hole. In this application, by providing the mounting base 3 at the mounting through-hole 101, only the end cover 5 needs to be disassembled and assembled every time the camshaft timing is positioned, without the need to disassemble and assemble the mounting base 3 and the bolt 7, and it will not cause damage to the structure of the fuel injection pump housing 1, which can ensure the reliability of the fuel injection pump housing 1.

[0042] In some embodiments, a seal is provided between the ear portion 302 and the fuel injection pump housing 1, and the seal forms a seal between the mounting base 3 and the fuel injection pump housing 1. With the above technical solution, providing the seal can maintain the sealing performance between the mounting base 3 and the fuel injection pump housing 1. In specific implementation, the seal can be a gasket.

[0043] As a preferred example, in order to improve the installation convenience of the retaining pin 4, a first guiding portion 408 is provided at the end of the pin head section 401, a second guiding portion 409 is provided at the end of the first pin body section 402, and a third guiding portion 410 is provided at the end of the second pin body section 404. In specific implementation, the guiding portion can be formed by chamfering. In specific implementation, the retaining pin 4 can be set as an integrally formed part.

[0044] As a preferred example, a positioning disk is provided on the camshaft 2 of the fuel injection pump, and a notch is provided at the edge of the positioning disk. The notch forms a clamping groove 201, and the pin head section 401 can be set as a flat shaft section matching the clamping groove 201. Setting the clamping groove 201 as a notch structure can reduce the difficulty of the flat shaft section being inserted into the clamping groove 201. In specific implementation, the central axes of the clamping pin 4, the mounting seat 3, and the mounting through hole 101 are all arranged along a radial direction of the camshaft 2 of the fuel injection pump.

[0045] As Figure 4 shown, the present invention also provides a fuel injection pump, including the timing positioning structure described in any one of the above. In specific implementation, a plurality of electronically controlled unit pumps 8 can be installed in the fuel injection pump.

[0046] The above embodiments are only preferred embodiments given to fully illustrate the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples", etc. means that the specific features, structures, materials or characteristics of the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

Claims

1. A timing positioning structure, characterized in that: It includes a fuel injection pump housing, a fuel injection pump camshaft, a mounting seat, a bayonet and an end cover; A clamping groove is arranged on the peripheral side of the camshaft of the fuel injection pump, and a mounting through hole is arranged on the housing of the fuel injection pump; The mounting seat is fixedly mounted at the mounting through hole, and a step through hole coaxial with the mounting through hole is arranged in the mounting seat, and the step through hole includes a small aperture section, a step surface and a large aperture section arranged in sequence from the inside to the outside; The end cover is detachably fixedly connected to the outer side of the mounting seat, the end cover closes the port of the step through hole on the outer side, and the end cover and the large-diameter section enclose a receiving space; The bayonet pin includes a pin head section, a first pin body section, an outer convex ring and a second pin body section connected in sequence, and the bayonet pin has a first installation position and a second installation position. When the bayonet pin is located at the first installation position, the outer convex ring is supported on the step surface, the first pin body section cooperates with the small-diameter section, the pin head section extends into the inner cavity of the fuel injection pump housing and is snapped into the slot to limit the circumferential position of the fuel injection pump camshaft, and the second pin body section is accommodated in the accommodating space; when the bayonet pin is located at the second installation position, the outer convex ring is supported on the step surface, the second pin body section cooperates with the small-diameter section, the pin head section and the first pin body section are accommodated in the accommodating space, and the bayonet pin and the fuel injection pump camshaft are separated from each other.

2. The timing positioning structure according to claim 1, characterized in that: The second pin body section is provided with an outer annular groove, in which a sealing ring is installed. When the bayonet is located at the second installation position, the sealing ring forms a seal between the second pin body section and the small aperture section.

3. The timing positioning structure according to claim 1, characterized in that: A threaded hole is arranged on the end surface of the second pin body section facing away from the outer convex ring.

4. The timing positioning structure according to claim 1, characterized in that: The large-diameter section is provided with an internal thread, and the end cover is provided with an external thread, and the internal thread cooperates with the external thread to detachably and fixedly connect the end cover to the outer side of the mounting seat.

5. The timing positioning structure according to claim 1, characterized in that: A blind hole with an opening facing inward is provided in the end cover, the inner diameter of the blind hole is smaller than the outer diameter of the outer convex ring, the inner diameter of the blind hole is larger than the outer diameter of the first pin body section and the outer diameter of the pin head section, and the inner diameter of the blind hole is larger than the outer diameter of the second pin body section.

6. The timing positioning structure according to claim 1, characterized in that: A sealing gasket is sandwiched between the end cover and the mounting seat, and the sealing gasket forms a seal between the end cover and the mounting seat.

7. The timing positioning structure according to claim 1, characterized in that: The mounting seat comprises a matching portion matched with the mounting through hole and an ear portion protruding from the matching portion in a radial direction of the matching portion, and the ear portion is fixedly connected to the fuel injection pump housing by bolts.

8. The timing positioning structure according to claim 7, characterized in that: A sealing member is arranged between the ear and the fuel injection pump housing, and the sealing member forms a seal between the mounting seat and the fuel injection pump housing.

9. A fuel injection pump, characterized in that: It comprises the timing positioning structure as described in any one of claims 1-8.

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