Anti-oil-leakage structure of common rail pipe

Abstract

This utility model discloses a common rail leak prevention structure, belonging to the field of engine technology. It includes multiple enclosures, each housing a section of common rail. A leak outlet is provided at the bottom of each enclosure, and the leak outlets of adjacent enclosures are connected via return pipes. The return pipe at the bottom of the end enclosure is connected to a collection box. A level sensor is installed in the collection box and connected to the ECU via a wire. The use of multiple enclosures arranged in a relatively continuous manner reduces manufacturing costs. In case of fuel leakage, the entire enclosure does not need to be disassembled; only the leaking enclosure needs to be disassembled for repair and replacement, facilitating maintenance. Connecting the leak outlets of adjacent enclosures via return pipes and connecting the return pipe at the bottom of the end enclosure to the collection box, where a level sensor monitors for leaks and collects leaked fuel, further saves costs by using only one level sensor across multiple enclosures.

Description

Technical Field

[0001] This utility model belongs to the field of engine technology, specifically relating to a structure for preventing common rail oil leakage. Background Technology

[0002] The statements in this section are merely background information related to this utility model and do not necessarily constitute prior art.

[0003] The common rail is a component of an electronically controlled high-pressure common rail system, connecting several high-pressure oil pipes through which high-pressure fuel flows. Currently, in a certain mining truck's V-type engine (a V-type engine divides all cylinders into two groups, arranging adjacent cylinders at a certain angle), the exhaust pipe is located outside the V-angle. Considering space and cost factors, the common rail is fixed to the cooling system's water outlet pipe, located above the exhaust pipe. If a leak occurs at the joint between the high-pressure oil pipe and the common rail, fuel will leak onto the high-temperature exhaust pipe, potentially causing an open flame and affecting engine reliability.

[0004] To ensure the safety of the common rail, a protective cover is usually installed on the outside of the common rail. For example, an integrated pipeline and an engine disclosed in the prior art include an intake manifold, a high-pressure common rail, and a protective cover. The high-pressure common rail is installed and fixed on the upper surface of the outside of the intake manifold, and the protective cover is connected to the upper part of the intake manifold and forms a sealed space with the intake manifold to accommodate the high-pressure common rail. Multiple fuel venting channels and leakage sensors are also provided for fuel leak alarm, leaked fuel discharge, and leaked fuel emptying functions.

[0005] While the above solution can prevent fuel from leaking out of the protective shield when a leak occurs at the joint between the high-pressure oil pipe and the common rail, it still has the following shortcomings: The protective shield is installed on the outside of the intake pipe to provide continuous protection for the common rail. This means that when a leak is found in the common rail, the entire protective shield needs to be removed to find the leak, which is time-consuming and laborious. In addition, the continuous installation will increase the cost of the protective shield. Utility Model Content

[0006] To address the aforementioned issues, this invention provides a common rail leak prevention structure. By setting multiple protective covers to protect the common rail, it can prevent fuel leakage onto the high-temperature exhaust pipe. Compared to a continuous protective cover, this reduces manufacturing costs. Furthermore, in case of fuel leakage, there is no need for complete disassembly; only the leaking cover needs to be removed for repair and replacement, facilitating maintenance. Simultaneously, leakage outlets are provided at the bottom of multiple covers, and the leakage outlets of adjacent covers are connected via return pipes. The return pipes at the bottom of the end covers are connected to a collection box (mounted on the vehicle). A level sensor is installed in the collection box to monitor for leaks and collect leaked fuel. The fact that only one level sensor is needed for multiple covers also saves costs.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A common rail leak prevention structure for a V-type engine includes multiple covers arranged sequentially on the water outlet pipe, with a section of common rail installed inside each cover.

[0009] An oil leakage outlet is provided at the bottom of the cover, and a hollow bolt oil pipe connector is fixedly connected to the oil leakage outlet. The oil leakage outlets of adjacent covers are connected through a return oil pipe. An oil collection box is connected to the bottom of one end of the cover. A liquid level sensor is installed in the oil collection box and is connected to the ECU through the vehicle wiring harness.

[0010] Preferably, the cover includes a lower cover integrated on the water outlet pipe, and the side of the lower cover away from the water outlet pipe is connected to the upper cover by a second bolt; a sealed space for accommodating the common rail pipe is formed between the upper cover and the lower cover.

[0011] Preferably, the water outlet pipe is divided into multiple sections, which are connected by flanges, and each section of the water outlet pipe is equipped with a lower cover.

[0012] Preferably, both the lower and upper cover are hollow shells with one open side and the other closed side; the lower and upper cover are provided with multiple second threaded holes in the circumference, and the second bolts are connected to the internal threads of the second threaded holes.

[0013] Preferably, one side of the common rail is connected to multiple high-pressure oil pipes via a connector, and the two ends of the other side are respectively provided with connecting lugs, and the connecting lugs are provided with first threaded holes.

[0014] Preferably, inside the lower cover, there are connecting protrusions at both ends of the bottom, and the connecting protrusions are provided with first threaded holes, and first bolts are connected to the first threaded holes.

[0015] Preferably, at both ends of the cover, above the connecting protrusion, common rail end holes are opened on the cover shell; at the top of the cover, multiple high-pressure oil pipe holes are opened.

[0016] Preferably, the diameter of the high-pressure oil pipe hole is larger than that of the high-pressure oil pipe, and a sealing plug is provided between the high-pressure oil pipe hole and the high-pressure oil pipe.

[0017] Preferably, a pressure plate is provided on the sealing plug, the pressure plate is threadedly connected to the cover, and multiple high-pressure fuel avoidance grooves are opened on the pressure plate. The number and position of the high-pressure fuel avoidance grooves are consistent with the high-pressure fuel pipe holes.

[0018] Preferably, the V-type engine is equipped with a cover for every two cylinders.

[0019] Compared with the prior art, the advantages and positive effects of this utility model are:

[0020] This invention protects the common rail by setting multiple protective covers, preventing fuel leakage onto the high-temperature exhaust pipe. Compared to a continuous protective cover, this reduces manufacturing costs. Furthermore, in case of fuel leakage, the entire system can be disassembled; only the leaking cover needs to be removed for repair or replacement, facilitating maintenance. Additionally, leak outlets are located at the bottom of the multiple covers, connecting adjacent covers via return pipes. The return pipes at the bottom of the end covers are connected to a collection box (mounted on the vehicle). A level sensor in the collection box monitors for leaks and collects leaked fuel. The fact that only one level sensor is needed for multiple covers also saves costs. Attached Figure Description

[0021] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.

[0022] Figure 1 This is an overall schematic diagram of the anti-common rail oil leakage structure according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the lower cover of an embodiment of the present utility model;

[0024] In the picture:

[0025] 1. Common rail; 2. High-pressure oil pipe; 3. Connector; 4. Leakage outlet; 5. Vent pipe; 6. Sealing plug; 7. Pressure plate; 8. Lower cover; 9. Return oil pipe; 10. Upper cover; 11. Water outlet pipe. Detailed Implementation

[0026] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0027] The present invention will now be described in detail with reference to the accompanying drawings. This embodiment discloses a common rail leak prevention structure for a V-type engine, such as... Figure 1 As shown, it includes multiple enclosures, each enclosure containing a section of common rail pipe 1; the enclosure includes a lower enclosure 8 integrated on the water outlet pipe 11, multiple sections of common rail pipe 1 are respectively installed on multiple lower enclosures 8, and the side of the lower enclosure 8 away from the water outlet pipe 11 is connected to the upper enclosure 10 by a second bolt; a sealed space is formed between the upper enclosure 10 and the lower enclosure 8 to accommodate the common rail pipe 1.

[0028] like Figure 1 As shown, a leak outlet 4 is provided at the bottom of the enclosure. A hollow bolt oil pipe connector is fixedly installed on the leak outlet 4 (for example, the leak outlet 4 is provided with an internal thread and is fixedly connected to the hollow bolt oil pipe connector by thread). The leak outlet 4 is connected to the return oil pipe 9 through the hollow bolt oil pipe connector to discharge the leaked fuel inside the enclosure.

[0029] Furthermore, multiple covers are sequentially arranged on the water outlet pipe, which has ends A and B. The bottom of the cover closest to end A uses a single-hole hollow bolt oil pipe connector, while the bottoms of the remaining covers use double-hole hollow bolt oil pipe connectors. Even further, the leakage outlets 4 of adjacent covers are connected via return oil pipes 9. At the bottom of the cover closest to end B, double-hole hollow bolt oil pipe connectors connect to the return oil pipe 9 and the oil collection box, respectively. The oil collection box has two ports: one port connects to the leakage outlet 4 at the bottom of the cover at end B via an oil collection pipe, and the other port is open to the atmosphere. The oil collection box can be mounted on the vehicle frame.

[0030] Understandably, when fuel leaks from the common rail 1 inside the enclosure, since the enclosure is a sealed space and the oil collection box is open to the atmosphere, high-pressure fuel flows out from the leak outlet 4 and then flows into the oil collection box for collection via the return oil pipe 9.

[0031] To monitor leaks in the cover and repair leaks promptly, a level sensor is installed in the oil collection box and connected to the ECU (Electronic Control Unit) via the machine's wiring harness. When the cover leaks, the leaked hydraulic oil flows into the oil collection box and reaches a set amount (e.g., 50ml). At this point, the level sensor transmits the monitoring information to the ECU, indicating that a leak has occurred inside the cover.

[0032] Unlike traditional methods where the entire protective cover needs to be disassembled for inspection, in this embodiment, upon discovering a leak inside the cover, the driver can simply disassemble multiple covers individually for inspection, and then repair or replace the components inside the leaking cover.

[0033] It should also be noted that the reason why the return oil pipe 9 of each enclosure is not connected to a separate oil collection box and a liquid level sensor is not installed in each oil collection box is that the leakage of the V-type engine used in mining trucks is not large when a leak occurs. Installing an oil collection box in each enclosure and a liquid level sensor in each oil collection box would undoubtedly increase the manufacturing cost.

[0034] It is important to note that the fuel collection box must be placed away from high-temperature components (such as the exhaust pipe) to avoid the high temperature affecting the fuel or level sensor.

[0035] like Figure 1 As shown, on one side of the common rail pipe 1, multiple high-pressure oil pipes 2 are connected along the axial direction of the common rail pipe 1. The common rail pipe 1 and the high-pressure oil pipes 2 are connected together by a joint 3. On the opposite side of the joint 3, a connecting ear plate is provided at each end of the common rail pipe 1. The connecting ear plate has a first threaded hole for installing the common rail pipe 1 on the lower cover 8.

[0036] Furthermore, the common rail 1 is provided with multiple protruding threaded interfaces for connecting to the high-pressure oil pipe 2 via a connector 3.

[0037] In this embodiment, the common rail 1 is provided with four protruding threaded interfaces, so four high-pressure oil pipes 2 are connected to the common rail 1. The four protruding threaded interfaces are symmetrically divided into two groups along the centerline of the axial length of the common rail 1, and each group includes two protruding threaded interfaces. It should be noted that each high-pressure oil pipe is connected to one injector.

[0038] like Figure 1 , Figure 2 As shown, the lower enclosure 8 is a rectangular hollow shell with an opening on one side and a fixed connection to the water outlet pipe 11 on the other side. The bottom of the lower enclosure 8 is provided with a leakage oil outlet 4, which is connected to the return oil pipe 9 to discharge the leaked fuel inside the enclosure and prevent the fuel from burning under the influence of the high-temperature exhaust pipe 5.

[0039] like Figure 1 , Figure 2 As shown, inside the lower cover 8, connecting protrusions are provided at the bottom of both ends. The connecting protrusions are provided with corresponding first threaded holes. The common rail tube 1 is placed inside the lower cover 8, and the first bolt is inserted into the first threaded hole to install the common rail tube 1 inside the lower cover 8. The lower cover 8 can fix the common rail tube 1.

[0040] like Figure 1 , Figure 2 As shown, at both ends of the lower cover 8, above the connecting protrusion, a semi-circular common rail pipe end hole is provided on the cover housing; threaded joints are provided at both ends of the common rail pipe 1, and the internal condition of the common rail pipe 1 can be inspected by opening the threaded joints; the threaded joints at both ends of the common rail pipe 1 are located at the common rail pipe end hole, as shown. Figure 1 As shown, the threaded connector extends out of the common rail pipe end hole, allowing the internal condition of the common rail pipe 1 to be inspected by opening the threaded connector without opening the cover.

[0041] like Figure 1 , Figure 2 As shown, multiple semi-circular high-pressure oil pipe holes are provided on the top of the lower cover 8 for the high-pressure oil pipe 2 to pass through and extend out of the lower cover 8. In this embodiment, there are four high-pressure oil pipes, so there are also four high-pressure oil pipe holes, which correspond to the positions of the four protruding threaded interfaces installed on the common rail pipe 1 of the lower cover 8.

[0042] like Figure 1 , Figure 2 As shown, along the circumference of the lower cover 8, a plurality of second threaded holes are provided on the side wall of the lower cover 8. The second threaded holes are arranged perpendicular to the axis of the lower cover 8 and are used to connect with the upper cover 10. In this embodiment, six second threaded holes are provided at the four corners of the lower cover 8 and at the midline of its axial length.

[0043] like Figure 1 As shown, the upper cover 10 also has an equal number of second threaded holes in the circumferential direction, and the corresponding second threaded holes are connected together by the second bolts, so that the upper cover 10 and the lower cover 8 are tightly connected.

[0044] It should be noted that the upper enclosure 10 is also a rectangular hollow shell, and its dimensions are the same as those of the lower enclosure 8; after the upper enclosure 10 and the lower enclosure 8 are connected, they form a closed space to accommodate the common rail tube 1; as Figure 1 As shown, the upper cover 10 also has semi-circular common rail pipe end holes at both ends, which cooperate with the lower cover 8 to house and seal the common rail pipe 1 inside the cover; the upper cover 10 has the same number and position of semi-circular high-pressure oil pipe holes. In some embodiments, sealing rings are provided at the common rail pipe end holes to enhance the sealing of both ends of the common rail pipe.

[0045] like Figure 1As shown, the high-pressure oil pipe 2 extends from the high-pressure oil pipe hole at the top of the upper cover 10 and the lower cover 8. The high-pressure oil pipe hole and the high-pressure oil pipe 2 are in direct contact, which will form a gap between them. When fuel leaks at the joint 3 between the high-pressure oil pipe 2 and the common rail pipe 1, the high-pressure fuel may be sprayed out from the gap between the high-pressure oil pipe hole and the high-pressure oil pipe 2 due to the closed space formed between the upper cover 10 and the lower cover 8, resulting in fuel leakage. This fuel may then come into contact with the high-temperature exhaust pipe and cause an open flame.

[0046] To prevent high-pressure fuel from potentially spraying out from the gap between the high-pressure fuel line orifice and high-pressure fuel line 2, such as... Figure 1 , Figure 2 As shown, the diameter of the high-pressure oil pipe hole is larger than that of the high-pressure oil pipe 2, and a sealing plug 6 is set between the high-pressure oil pipe hole and the high-pressure oil pipe 2; the high-pressure oil pipe hole is shaped like a frustum, with the smaller diameter end set on the inner wall of the cover.

[0047] like Figure 1 As shown, the sealing plug 6 is also frustum-shaped, and its height is greater than that of the high-pressure oil pipe hole. The end of the sealing plug 6 with a larger diameter is larger than the end of the high-pressure oil pipe hole with a larger diameter, and the end of the sealing plug 6 with a smaller diameter is smaller than the end of the high-pressure oil pipe hole with a smaller diameter.

[0048] like Figure 1 As shown, a high-pressure oil pipe through hole is drilled in the center of the sealing plug 6 for the high-pressure oil pipe 2 to pass through; after the sealing plug 6 is passed through the high-pressure oil pipe 2, the sealing plug 6 is installed in the high-pressure oil pipe hole to avoid gaps between the high-pressure oil pipe hole and the high-pressure oil pipe 2.

[0049] Because a closed space is formed between the upper cover 10 and the lower cover 8, when fuel leaks at the joint 3 between the high-pressure oil pipe 2 and the common rail pipe 1, the high-pressure fuel may push up the sealing plug 6, thus creating a leakage path for fuel injection in the high-pressure oil pipe hole. To prevent the sealing plug 6 from being pushed up and causing fuel injection, a pressure plate 7 is also provided in this embodiment to press down the sealing plug 6.

[0050] Specifically, such as Figure 1 As shown, the pressure plate 7 is installed above the upper cover 10 and the lower cover 8. The pressure plate 7 has multiple high-pressure fuel avoidance grooves. The number and position of the high-pressure fuel avoidance grooves are consistent with the high-pressure fuel pipe holes. Multiple third threaded holes are opened along the circumference of the pressure plate 7. Correspondingly, multiple third threaded holes are also opened at the corresponding positions on the top of the upper cover 10 and the lower cover 8. The pressure plate 7 is installed on the top of the upper cover 10 and the lower cover 8 by passing a third bolt through the third threaded hole.

[0051] It should be noted that the third threaded hole opened on the upper cover 10 and the lower cover 8 must not penetrate the side wall of the upper cover 10 and the lower cover 8.

[0052] like Figure 1 As shown, the water outlet pipe 11 is divided into multiple sections, and the water outlet pipes 11 are connected by flanges. Each section of the water outlet pipe 11 is equipped with a common rail pipe 1, as well as an upper cover 10 and a lower cover 8.

[0053] Considering that V-type engines divide all cylinders into two groups, arranging adjacent cylinders together at a certain angle; existing mining trucks use V-type engines of 8, 12, 16, and 20 cylinders. In this embodiment, a cover is provided for every two cylinders; thus, it is applicable to V-type 8, 12, 16, and 20 cylinder models, offering good versatility; compared to a continuous protective cover, the two-cylinder section cover design is easier to process than a one-piece cover, and correspondingly, the processing cost is also reduced due to the shorter length.

[0054] In this embodiment, taking a V12 engine as an example, when a leak is detected inside the cover, all six covers can be disassembled for inspection. In practice, during the inspection, the cover where the fuel leak is observed to have a slight fuel seepage between the sealing plug 6 and the high-pressure fuel line hole. After identifying the cover corresponding to two specific cylinders, only the common rail connector at the leak point needs to be repaired or replaced. However, the entire protective cover needs to be disassembled before inspection and replacement of the internal common rail, and then the entire protective cover needs to be reinstalled, which is time-consuming and labor-intensive.

[0055] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solution of the present utility model are still within the scope of protection of the present utility model.

Claims

1. A common rail leak prevention structure for a V-type engine, characterized in that, It includes multiple covers arranged sequentially on the water outlet pipe, with a section of common rail pipe installed inside each cover; An oil leakage outlet is provided at the bottom of the cover, and a hollow bolt oil pipe connector is fixedly connected to the oil leakage outlet. The oil leakage outlets of adjacent covers are connected through a return oil pipe. An oil collection box is connected to the bottom of one end of the cover. A liquid level sensor is installed in the oil collection box and is connected to the ECU through the vehicle wiring harness.

2. The anti-leakage structure for common rail pipes as described in claim 1, characterized in that, The enclosure includes a lower enclosure integrated on the water outlet pipe, and the side of the lower enclosure away from the water outlet pipe is connected to the upper enclosure by a second bolt; a sealed space is formed between the upper enclosure and the lower enclosure to accommodate the common rail pipe.

3. The anti-leakage structure for common rail pipes as described in claim 2, characterized in that, The water outlet pipe is divided into multiple sections, which are connected by flanges. Each section of the water outlet pipe is equipped with a lower cover.

4. The anti-leakage structure for common rail pipes as described in claim 2, characterized in that, Both the lower and upper covers are hollow shells, with one side open and the other side closed; the lower and upper covers are provided with multiple second threaded holes around their circumference, and the second bolts are connected to the threads inside the second threaded holes.

5. The anti-leakage structure for common rail pipes as described in claim 1, characterized in that, The common rail is connected to multiple high-pressure oil pipes on one side via a connector, and connecting lugs are provided at both ends of the other side, with a first threaded hole on the connecting lug.

6. The anti-leakage structure for common rail pipes as described in claim 1, characterized in that, Inside the lower cover, there are connecting protrusions at both ends of the bottom, and the connecting protrusions are provided with first threaded holes, and the first bolts are connected to the first threaded holes.

7. The anti-leakage structure for common rail pipes as described in claim 1, characterized in that, At both ends of the cover, above the connecting protrusion, common rail pipe end holes are opened on the cover shell; at the top of the cover, multiple high-pressure oil pipe holes are opened.

8. The anti-common rail oil leakage structure as described in claim 7, characterized in that, The diameter of the high-pressure oil pipe hole is larger than that of the high-pressure oil pipe, and a sealing plug is installed between the high-pressure oil pipe hole and the high-pressure oil pipe.

9. The anti-common rail oil leakage structure as described in claim 8, characterized in that, A pressure plate is provided on the sealing plug. The pressure plate is threadedly connected to the cover. Multiple high-pressure fuel avoidance grooves are opened on the pressure plate. The number and position of the high-pressure fuel avoidance grooves are consistent with the high-pressure oil pipe holes.

10. The anti-common rail oil leakage structure as described in claim 1, characterized in that, The V-type engine has a cover for every two cylinders.

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