CN214741778U - Common rail pipe - Google Patents

Abstract

The utility model relates to a common rail pipe, which comprises an inner pipe; the connecting blocks are sleeved on the inner pipe at intervals, and an oil return cavity is formed between the inner wall of each connecting block and the outer wall of the inner pipe; the oil return cavities are arranged on the inner pipe in a sleeved mode, the two ends of each outer pipe are respectively inserted into the two adjacent oil return cavities in a sealing mode, and an oil drainage channel is formed between the inner wall of each outer pipe and the outer wall of the inner pipe; the method is characterized in that: at least one of the oil drainage channels is internally restricted with a sealing ring, a first groove is arranged on the inner wall of the sealing ring, a first sealing ring which is in sealing and abutting contact with the outer wall of the inner pipe is arranged in the first groove, a second groove is arranged on the outer wall of the sealing ring, and a second sealing ring which is in sealing and abutting contact with the inner wall of the outer pipe is arranged in the second groove. The utility model relates to a common rail pipe can reduce the fluting and need not the fluting even, thereby is difficult to fracture life longer.

Description

Common rail pipe

Technical Field

The utility model relates to a diesel engine common rail system technical field specifically is a common rail pipe.

Background

The common rail pipe is used as an important component in a common rail system of the diesel engine, and is mainly used for storing high-pressure diesel oil, reducing pressure fluctuation and controlling injection pressure.

Among the prior art, the common rail pipe mainly includes the inner tube, and the interval cover is located a plurality of connecting blocks and a plurality of outer tubes on the inner tube form back oil cavity between each connecting block inner wall and the inner tube outer wall, and the both ends of each outer tube are sealed respectively and are pegged graft in two adjacent oil return cavities, and form the draining passageway that feeds through with each time oil cavity between each outer tube inner wall and the inner tube outer wall, and each draining passageway and each time oil return cavity form the oil return runner jointly. Generally, in order to check an oil leakage section of the common rail pipe, a seal ring is required to be arranged in each oil leakage passage to divide an oil return flow passage into a plurality of sub-flow passages which are independent from each other, and once high-pressure fuel oil leaks and flows out from a pressure relief opening on a pipe joint, the oil leakage section on the common rail pipe can be found out quickly.

The chinese utility model patent with patent number ZL201921631460.9 (the publication number of grant is CN210799204U) discloses a double-walled double-rail pipe, through set up the recess on the inner tube outer wall, be equipped with in the recess with outer tube inner wall sealing connection's O type sealing washer to separate into a plurality of mutually independent sub-runners with the oil return runner. However, the common rail pipe has the following disadvantages: because the sealing washer is more in the common rail pipe, offer a large amount of recesses on the inner tube and can make the common rail pipe material produce stress, make the bearing capacity of common rail pipe decline, the common rail pipe produces pipe wall fatigue easily and leads to the fracture in the work operation, influences the life of common rail pipe.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a thereby can reduce the fluting and need not the fluting even, be difficult to fracture thereby life is longer altogether rail pipe is provided to foretell technical situation.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: a common rail pipe comprises

The inner pipe is provided with a plurality of inner pipes,

the connecting blocks are sleeved on the inner pipe at intervals, and an oil return cavity is formed between the inner wall of each connecting block and the outer wall of the inner pipe;

the oil return cavities are arranged on the inner pipe in a sleeved mode, the two ends of each outer pipe are respectively inserted into the two adjacent oil return cavities in a sealing mode, and an oil drainage channel is formed between the inner wall of each outer pipe and the outer wall of the inner pipe;

the method is characterized in that:

at least one of the oil drainage channels is internally restricted with a sealing ring, a first groove is arranged on the inner wall of the sealing ring, a first sealing ring which is in sealing and abutting contact with the outer wall of the inner pipe is arranged in the first groove, a second groove is arranged on the outer wall of the sealing ring, and a second sealing ring which is in sealing and abutting contact with the inner wall of the outer pipe is arranged in the second groove.

In order to make the flow area of the oil drainage channel smaller, the first groove and the second groove are sequentially distributed along the axial direction of the sealing ring.

In order to facilitate the assembly of the sealing ring, the sealing ring is arranged close to one end of the outer pipe. When the sealing ring is assembled, the sealing ring and the outer pipe are assembled together and then sleeved on the inner pipe.

In order to facilitate the restraint of the sealing ring, a first step part is formed at one end part close to the outer pipe, the first step part enables the outer pipe to be provided with a large-diameter hole close to one end part of the outer pipe and a small-diameter hole far away from one end part of the outer pipe, and the sealing ring is located in the large-diameter hole and abuts against a step surface of the first step part.

Generally, a flow limiting valve in a common rail system is installed at a connecting rod of a high-pressure oil path and an oil injector, the installation difficulty of the flow limiting valve and the high-pressure oil pipe is high, and when fuel oil leaks due to breakage of the high-pressure oil pipe, the flow limiting valve installed at the connecting rod of the high-pressure oil path and the oil injector cannot close an oil path in the common rail pipe, so that the flow limiting function cannot be achieved. In order to enable the flow limiting valve to better limit the flow of the common rail system, a fuel oil channel is arranged in the inner pipe, a plurality of oil outlet holes communicated with the fuel oil channel are formed in the inner pipe, each oil outlet hole is respectively positioned in the corresponding oil return cavity, and at least one oil outlet hole is connected with the flow limiting valve used for conducting or blocking the high-pressure oil pipe and the fuel oil channel.

In order to make the structure of the current limiting valve simpler, the current limiting valve comprises

The valve body is provided with a first connecting part which is hermetically inserted into the oil return cavity at one end and a second connecting part which is hermetically connected with the high-pressure oil pipe at the other end, and the valve body is provided with an axially through valve cavity, and a valve hole is arranged on the wall of the valve cavity;

one end of the sealing head is hermetically inserted in the oil outlet, the other end of the sealing head is hermetically inserted in the valve cavity, and a first channel which is axially communicated is formed in the sealing head;

a valve needle which is axially movably arranged in the valve cavity in a penetrating way, and the valve needle can open or close the valve hole by axial movement, wherein a second passage which is communicated with the valve cavity and the first passage is arranged;

and the spring is sleeved on the valve needle and enables the valve needle to always have the trend of moving towards the sealing head.

In order to facilitate installation of the flow limiting valve, a pressing block is detachably connected to the connecting block, and the pressing block is sleeved on the valve body and presses the valve body towards the inner pipe.

In order to facilitate recovery of fuel leaked when the high-pressure oil pipe is broken, an oil return passage which is mutually independent of the valve cavity is arranged in the valve body, and the oil return passage is used for communicating the high-pressure oil pipe with the oil return cavity.

In a further design, a third groove is arranged on the first connecting part, and a third sealing ring which is in sealing and abutting contact with the inner wall of the connecting block is arranged in the third groove; and a fourth groove is formed in the second connecting part, and a fourth sealing ring which is used for being in sealing and abutting against the inner wall of the high-pressure oil pipe is placed in the fourth groove.

In a further design, one end of the sealing head is a third connecting part inserted into the oil outlet, the third connecting part is in a circular truncated cone shape, and the diameter of the third connecting part is gradually increased from one end of the sealing head to the other end of the sealing head; the other end of the sealing head is a fourth connecting part inserted in the valve cavity, the fourth connecting part comprises a cylindrical section and a circular table section which are sequentially distributed along the direction from one end of the sealing head to the other end, and the diameter of the circular table section is gradually reduced along the direction from one end of the sealing head to the other end; the valve hole is round platform form, and the one end of keeping away from on the needle sealed the head be can seal the grafting in the round platform portion in the valve hole.

Compared with the prior art, the utility model has the advantages of: there is the sealing ring through restraint in wherein at least one draining passageway, and between sealing ring inner wall and inner tube outer wall, all set up the sealing washer between sealing ring outer wall and the outer tube inner wall, thereby make and form independent draining passageway between each outer tube inner wall and the inner tube outer wall, can reduce the fluting on the inner tube and even need not to fluting on the inner tube, thereby can keep the bearing capacity of common rail pipe, make the common rail pipe be difficult for producing the pipe wall and fracture in the work operation, thereby the life of extension common rail pipe.

Drawings

FIG. 1 is a perspective view of an embodiment of the present invention;

fig. 2 is a partial cross-sectional view of an embodiment of the invention;

FIG. 3 is an enlarged view taken at A in FIG. 2;

fig. 4 is a partially exploded view of an embodiment of the present invention;

fig. 5 is an exploded perspective view of a flow limiting valve according to an embodiment of the present invention;

fig. 6 is a sectional view in the direction of B-B of the flow restriction valve in fig. 3.

Wherein the reference numerals in the above figures are:

11. an inner tube; 111. a fuel passage; 112. an oil outlet hole; 12. an outer tube; 121. a first step portion; 122. a large-diameter hole; 123. a small-diameter hole; 2. connecting blocks; 3. a valve body; 31. a first connection portion; 311. a third groove; 32. a second connecting portion; 321. a fourth groove; 33. a second step portion; 34. a valve cavity; 35. a valve bore; 36. an oil return passage; 37. a pin hole; 4. a sealing head; 41. a third connecting portion; 42. a fourth connecting portion; 421. a cylindrical section; 422. a circular table section; 43. a first channel; 5. a valve needle; 51. a second channel; 52. perforating; 53. a circular table portion; 6. a spring; 7. briquetting; 8. a seal ring; 81. a first groove; 82. a second groove; 91. a first seal ring; 92. a second seal ring; 93. a third seal ring; 94. a fourth seal ring, 100 and an oil return cavity; 200. a flow-limiting valve; 300. and an oil drainage channel.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

As shown in fig. 1-6, is a preferred embodiment of the present invention.

The common rail pipe in this embodiment includes main parts such as an inner pipe 11, an outer pipe 12, a connecting block 2, a valve body 3, a sealing head 4, a valve needle 5, a spring 6, a pressing block 7, a sealing ring 8, a first sealing ring 91, a second sealing ring 92, a third sealing ring 93, and a fourth sealing ring 94.

The connecting blocks 2 are multiple and are sleeved on the inner pipe 11 at intervals (see fig. 1), and an oil return cavity 100 (see fig. 3) is formed between the inner wall of each connecting block 2 and the outer wall of the inner pipe 11. The outer tube 12 is plural and a spacer is provided on the inner tube 11 (see fig. 1). Two ends of each outer tube 12 are respectively sealed and inserted into two adjacent oil return cavities 100, and an oil drainage channel 300 (see fig. 3) is formed between the inner wall of each outer tube 12 and the outer wall of the inner tube 11. As shown in fig. 3, a sealing ring 8 is constrained in each oil drainage channel 300, a first groove 81 is arranged on the inner wall of the sealing ring 8, and a first sealing ring 91 which is in sealing contact with the outer wall of the inner pipe 11 is placed in the first groove 81; the outer wall of the sealing ring 8 is provided with a second groove 82, and a second sealing ring 92 which is in sealing contact with the inner wall of the outer tube 12 is arranged in the second groove 82. The common rail pipe in the embodiment does not need to be grooved on the inner pipe 11, and the pressure bearing capacity of the common rail pipe can be maintained, so that the common rail pipe is not easy to break due to pipe wall generation in the working operation process, and the service life of the common rail pipe is prolonged.

As shown in fig. 3, the first groove 81 and the second groove 82 are distributed in this order in the axial direction of the seal ring 8. The sealing ring 8 is arranged close to one end of the outer tube 12. Specifically, a first stepped portion 121 is formed near one end of the outer tube 12, the first stepped portion 121 causes the outer tube 12 to have a large-diameter hole 122 near the one end thereof and a small-diameter hole 123 far from the one end thereof, and the seal ring 8 is located in the large-diameter hole 122 and abuts against a stepped surface of the first stepped portion 121.

As shown in fig. 3, the inner tube 11 has a fuel passage 111 therein, the inner tube 11 is provided with a plurality of oil outlet holes 112 communicated with the fuel passage 111, each oil outlet hole 112 is respectively located in the corresponding oil return chamber 100, and each oil outlet hole 112 is connected with a flow restriction valve 200 for communicating or blocking the high pressure oil pipe and the fuel passage 111. As shown in fig. 5 to 6, the flow restriction valve 200 includes a valve body 3, a sealing head 4, a valve needle 5, and a spring 6.

One end of the valve body 3 is a first connecting part 31 which is hermetically inserted in the oil return cavity 100; specifically, the first connecting portion 31 is provided with a third groove 311 (see fig. 5-6), and a third sealing ring 93 (see fig. 3) is disposed in the third groove 311 and is in sealing contact with the inner wall of the connecting block 2. The other end of the valve body 3 is provided with a second connecting part 32 which is used for being connected with a high-pressure oil pipe in a sealing way; specifically, the second connecting portion 32 is provided with a fourth groove 321 (see fig. 5-6), and a fourth sealing ring 94 (see fig. 3) for sealing against the inner wall of the high-pressure oil pipe is disposed in the fourth groove 321. The valve body 3 is provided with a second step part 33 (see fig. 5-6), the valve body 3 is sleeved with a pressing block 7 which is detachably connected with the connecting block 2 through a screw, and the pressing block 7 is placed on the step surface of the second step part 33 and used for pressing the valve body 3 towards the direction of the inner pipe 11 (see fig. 3-4). As shown in fig. 3 and 6, the valve body 3 has a valve chamber 34 extending axially therethrough, and a valve hole 35 is provided in a wall of the valve chamber 34. As shown in fig. 3, the valve body 3 is provided therein with an oil return passage 36 independent of the valve chamber 34 for communicating the high-pressure oil pipe and the oil return chamber 100.

As shown in fig. 5 to 6, one end of the seal head 4 is a third connection portion 41 inserted into the oil outlet hole 112, the third connection portion 41 is in a circular truncated cone shape, and the diameter of the third connection portion 41 gradually increases from one end to the other end of the seal head 4, so that the third connection portion 41 and the oil outlet hole 112 are hermetically connected. As shown in fig. 5 to 6, the other end of the sealing head 4 is a fourth connecting portion 42 inserted into the valve cavity 34, the fourth connecting portion 42 includes a cylindrical section 421 and a circular truncated cone section 422 distributed in sequence from one end of the sealing head 4 to the other end, and the diameter of the circular truncated cone section 422 gradually decreases from one end of the sealing head 4 to the other end, so that the fourth connecting portion 42 is connected with the valve cavity 34 in a sealing manner. As shown in fig. 3 and 6, the seal head 4 has a first passage 43 extending axially therethrough, and the first passage 43 communicates with a fuel passage 111.

As shown in fig. 3 and 6, the valve needle 5 is axially movably disposed through the valve cavity 34, and axial movement of the valve needle 5 opens or closes the valve hole 35. Specifically, as shown in fig. 3 and 6, the valve needle 5 is provided therein with a second passage 51 communicating with the first passage 43, and the valve needle 5 is provided thereon with a plurality of perforations 52 uniformly spaced in the circumferential direction, the second passage 51 communicating with the valve chamber 34 through the perforations 52. As shown in fig. 3 and 6, the valve hole 35 is circular truncated cone-shaped, and one end of the valve needle 5 away from the sealing head 4 is a circular truncated cone portion 53 which is inserted into the valve hole 35 in a sealing manner, so that the circular truncated cone portion 53 can block the valve hole 35. The valve hole 35 is opened when the land 53 of the valve needle 5 is escaped from the valve hole 35, and the valve hole 35 is closed when the land 53 of the valve needle 5 is sealingly inserted in the valve hole 35.

As shown in fig. 3 and 6, the spring 6 is sleeved on the valve needle 5 and makes the valve needle 5 always have a tendency to move towards the sealing head 4.

The working principle of the flow limiting valve 200 in this embodiment is as follows: when the common rail pipe normally runs, due to the elastic action of the spring 6, the valve needle 5 always has the tendency of propping against the sealing head 4 towards the direction of the inner pipe 11, the circular table part 53 on the valve needle 35 is separated from the valve hole 35, at the moment, the fuel passage 111, the first passage 43, the second passage 51 and the valve cavity 34 are sequentially communicated, the oil pressure in the valve cavity 34 and the oil pressure at the high-pressure oil pipe are kept balanced, and the common rail pipe can output high-pressure fuel oil; when the rear end of the common rail pipe fails, such as the burst of the high-pressure oil pipe, the blockage of the fuel injector and the like, which causes the imbalance of the oil pressure between the valve cavity 34 and the high-pressure oil pipe, the fuel in the fuel passage 111 can cause the valve needle 5 to move towards the valve hole 35 against the elastic action of the spring 6 until the circular table part 53 on the valve needle 35 is inserted into the valve hole 35 in a sealing way, and the valve needle 5 is separated from the sealing head 4, so that the communication between the fuel passage 111 and the high-pressure oil pipe is blocked, and the fuel leakage is prevented.

The assembling steps of the common rail pipe in the embodiment are as follows:

step one, a first sealing ring 91 is arranged in a first groove 81, a second sealing ring 92 is arranged in a second groove 82, a sealing ring is arranged in a connecting block 2, and a sealing ring 8 is arranged in an outer tube 12;

step two, inserting the inner pipes 11 into the plurality of connecting blocks 2 and the plurality of outer pipes 12 in sequence, and enabling the connecting blocks 2 and the outer pipes 12 to be distributed at intervals in sequence;

step three, a third sealing ring 93 is arranged in a third groove 311, a fourth sealing ring 93 is arranged in a fourth groove 321, a sealing head 4, a needle valve 5 and a spring 6 are sequentially inserted into a valve cavity 34 of the valve body 3, and a fastening screw is inserted into a pin hole 37 to fix the position of the sealing head 4, so that the flow limiting valve 200 is completely assembled;

and step four, inserting the flow limiting valve 200 into the oil return cavity 100, inserting the sealing head 4 into the oil return hole 112, and fixing the flow limiting valve 200 by using a pressure plate 7, a gasket, a spring gasket and a screw to enable the sealing head 4 and the oil return hole 112 to be connected in a sealing mode.

Claims (10)

1. A common rail pipe comprises

An inner tube (11),

the connecting blocks (2) are sleeved on the inner pipe (11) at intervals, and an oil return cavity (100) is formed between the inner wall of each connecting block (2) and the outer wall of the inner pipe (11);

the oil return cavities (100) are arranged in the inner pipe (11) in a sealed and inserted mode, the inner wall of each outer pipe (12) is connected with the outer wall of the inner pipe (11) in a sealed mode, and an oil drainage channel (300) is formed between the inner wall of each outer pipe (12) and the outer wall of the inner pipe (11);

the method is characterized in that:

a sealing ring (8) is constrained in at least one oil drainage channel (300), a first groove (81) is formed in the inner wall of the sealing ring (8), a first sealing ring (91) which is in sealing and abutting contact with the outer wall of the inner pipe (11) is placed in the first groove (81), a second groove (82) is formed in the outer wall of the sealing ring (8), and a second sealing ring (92) which is in sealing and abutting contact with the inner wall of the outer pipe (12) is placed in the second groove (82).

2. A common rail pipe as defined in claim 1, wherein: the first groove (81) and the second groove (82) are distributed in sequence along the axial direction of the sealing ring (8).

3. A common rail pipe as defined in claim 1, wherein: the sealing ring (8) is arranged close to one end part of the outer pipe (12).

4. A common rail pipe according to claim 3, wherein: and a first step part (121) is formed at one end part close to the outer pipe (12), the first step part (121) enables the outer pipe (12) to be provided with a large-diameter hole (122) close to one end part of the outer pipe and a small-diameter hole (123) far away from one end part of the outer pipe, and the sealing ring (8) is positioned in the large-diameter hole (122) and is abutted against the step surface of the first step part (121).

5. A common rail pipe according to any one of claims 1 to 4, wherein: the oil return device is characterized in that a fuel oil channel (111) is arranged in the inner tube (11), a plurality of oil outlet holes (112) communicated with the fuel oil channel (111) are formed in the inner tube (11), each oil outlet hole (112) is located in a corresponding oil return cavity (100), and at least one oil outlet hole (112) is connected with a flow limiting valve (200) used for conducting or blocking a high-pressure oil pipe and the fuel oil channel (111).

6. The common rail pipe of claim 5, wherein: the flow limiting valve (200) comprises

The valve body (3) is provided with a first connecting part (31) which is hermetically inserted into the oil return cavity (100) at one end and a second connecting part (32) which is hermetically connected with a high-pressure oil pipe at the other end, and is provided with an axially through valve cavity (34), and a valve hole (35) is arranged on the cavity wall of the valve cavity (34);

the sealing head (4) is inserted into the oil outlet hole (112) in a sealing mode at one end, inserted into the valve cavity (34) in a sealing mode at the other end, and provided with a first passage (43) which penetrates through the valve cavity in the axial direction;

a valve needle (5) axially movably disposed in the valve cavity (34) and axially moving the valve needle (5) to open or close the valve hole (35), wherein a second passage (51) communicating the valve cavity (34) and the first passage (43) is provided;

and the spring (6) is sleeved on the valve needle (5) and enables the valve needle (5) to always have the trend of moving towards the sealing head (4).

7. The common rail pipe of claim 6, wherein: the valve is characterized in that a pressing block (7) is detachably connected to the connecting block (2), and the pressing block (7) is sleeved on the valve body (3) and presses the valve body (3) towards the inner pipe (11).

8. The common rail pipe of claim 7, wherein: an oil return passage (36) which is independent of the valve cavity (34) is arranged in the valve body (3), and the oil return passage (36) is used for communicating the high-pressure oil pipe with the oil return cavity (100).

9. The common rail pipe of claim 7, wherein: a third groove (311) is formed in the first connecting part (31), and a third sealing ring (93) which is in sealing abutment with the inner wall of the connecting block (2) is arranged in the third groove (311); and a fourth groove (321) is formed in the second connecting part (32), and a fourth sealing ring (94) which is used for being in sealing abutment with the inner wall of the high-pressure oil pipe is placed in the fourth groove (321).

10. The common rail pipe of claim 7, wherein: one end of the sealing head (4) is a third connecting part (41) inserted into the oil outlet hole (112), the third connecting part (41) is in a circular truncated cone shape, and the diameter of the third connecting part (41) is gradually increased from one end of the sealing head (4) to the other end; the other end of the sealing head (4) is a fourth connecting part (42) inserted in the valve cavity (34), the fourth connecting part (42) comprises a cylindrical section (421) and a circular truncated cone section (422) which are sequentially distributed along the direction from one end to the other end of the sealing head (4), and the diameter of the circular truncated cone section (422) is gradually reduced along the direction from one end to the other end of the sealing head (4); the valve hole (35) is in a circular truncated cone shape, and one end, far away from the sealing head (4), of the valve needle (5) is a circular truncated cone portion (53) which can be plugged into the valve hole (35) in a sealing mode.

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