阅读说明：本技术 一种循环废气混合装置及柴油机 (Circulating exhaust gas mixing device and diesel engine ) 是由 李卫 张磊 潘洁 邹立臣 于 2019-12-20 设计创作，主要内容包括：本发明公开了一种循环废气混合装置,包括壳体,壳体内部设置有隔板,隔板将壳体的内腔分隔为混合腔和稳压腔,隔板上设置有通孔；混合腔内设置有循环废气管和空气管,循环废气管和空气管均为直管,循环废气管上布置有多个循环废气出孔,空气管上布置有多个空气出孔。在混合腔中,循环废气从循环废气出孔散出。由于隔板的阻挡作用,混合气体会在混合腔中产生蓄压,从而利于均匀混合。另外,在循环废气进气量大时,其流速足够大,因此能够确保混合的均匀性,此时调大循环废气出孔的流通面积,以减小泵压损失；在循环废气进气量小时,调小循环废气出孔的流通面积,以提高循环废气的流速,从而提高混合的均匀性。本发明还公开了一种柴油机。(The invention discloses a circulating waste gas mixing device which comprises a shell, wherein a partition plate is arranged in the shell, the partition plate divides an inner cavity of the shell into a mixing cavity and a pressure stabilizing cavity, and a through hole is formed in the partition plate; be provided with circulation exhaust pipe and air pipe in the mixing chamber, circulation exhaust pipe and air pipe are the straight tube, have arranged a plurality of circulation exhaust outlet on the circulation exhaust pipe, have arranged a plurality of air outlets on the air pipe. In the mixing chamber, the circulating exhaust gas escapes from the circulating exhaust gas outlet. Due to the blocking effect of the partition plate, the mixed gas can generate pressure accumulation in the mixing cavity, so that uniform mixing is facilitated. In addition, when the air inflow of the circulating exhaust gas is large, the flow velocity is large enough, so that the uniformity of mixing can be ensured, and the flow area of the circulating exhaust gas outlet is increased to reduce the pumping pressure loss; when the air inflow of the circulating waste gas is small, the flow area of the circulating waste gas outlet is reduced to improve the flow velocity of the circulating waste gas, so that the mixing uniformity is improved. The invention also discloses a diesel engine.)

1. A circulating waste gas mixing device is characterized by comprising a shell, wherein a partition plate is arranged in the shell and divides an inner cavity of the shell into a mixing cavity and a pressure stabilizing cavity, and a through hole for communicating the mixing cavity with the pressure stabilizing cavity is formed in the partition plate;

be provided with circulation exhaust pipe and air pipe in the mixing chamber, circulation exhaust pipe with the air pipe is the straight tube, a plurality of circulation exhaust outlet have been arranged on the circulation exhaust pipe, a plurality of air outlet have been arranged on the air pipe, the steady voltage chamber communicates with the cylinder.

2. The recirculating exhaust mixing device of claim 1 wherein a plurality of the through-holes are evenly distributed through the baffle plate.

3. The recirculating exhaust mixing device of claim 1 wherein the mixing chamber is a rectangular parallelepiped chamber, the partition has a rectangular cross-section, and the contoured edge portions of the partition are in series with the inner wall of the housing at the partition.

4. The circulating exhaust gas mixing apparatus according to claim 1, wherein the circulating exhaust gas pipe and the air pipe are arranged in parallel, and one of them is close to the partition plate with respect to the other.

5. The circulating exhaust gas mixing device according to claim 1, wherein two opposite slots are formed in the inner wall of the housing, openings of the two slots are opposite, and two wide side portions of the partition plate are respectively inserted into the two slots.

6. The circulating exhaust gas mixing device according to claim 1, wherein a convex cavity protruding outward is formed in the side plate in contact with one long side portion of the partition plate, the convex cavity communicates with the pressure maintaining cavity, and a port portion of the convex cavity is provided with a flange connected to the cylinder.

7. The circulating exhaust gas mixing apparatus as set forth in claim 6, wherein the side plate contacting the other long side portion of the partition is fixed by welding.

8. The recirculating exhaust mixing apparatus as set forth in claim 1 further comprising a recirculating exhaust fitting and an air fitting disposed on a side of the housing, the recirculating exhaust pipe communicating with the recirculating exhaust fitting, the air pipe communicating with the air fitting.

9. The circulating exhaust gas mixing device according to claim 1, wherein the circulating exhaust gas pipe is of a sleeve type structure and comprises an outer sleeve and an inner sleeve, circulating exhaust gas enters the inner sleeve, the outer sleeve is fixed relative to the housing, the tail ends of the outer sleeve and the inner sleeve are both blind ends, a pressure spring is arranged between the blind end of the outer sleeve and the blind end of the inner sleeve,

interior macropore and aperture are provided with along its axial interval on the interior sleeve pipe, be provided with a plurality of outer macropores along its axial on the outer tube, when the air input of circulation waste gas is little, the aperture on the interior sleeve pipe with outer macropore on the outer tube aligns, when the air input of circulation waste gas increases, interior sleeve pipe compression the pressure spring, interior macropore on the interior sleeve pipe gradually with outer macropore on the outer tube aligns.

10. The recirculating exhaust mixing device of claim 9 wherein the inner sleeve has a ring of the inner large openings and a ring of the small openings spaced axially therealong, and the outer sleeve has a plurality of rings of the outer large openings axially therealong.

11. The mixing device of claim 9, wherein the outer large hole and the inner large hole are both strip-shaped holes, and the small hole is a circular hole.

12. The exhaust gas recirculation mixing device according to claim 9, further comprising a compression ring which receives the compression force from the exhaust gas recirculation connector and applies the compression force to the end surfaces of the starting ends of the outer sleeve and the inner sleeve, the outer sleeve being compressed against the housing, the inner sleeve compressing the compression spring, and the exhaust gas recirculation connector being connected to the housing and communicating with the inner sleeve.

13. The recirculating exhaust mixing device of claim 12 wherein the recirculating exhaust fitting has a first flange, the housing has a second flange for mating with the first flange, the clamp ring is positioned in a central opening in the second flange, and an end surface of the first flange is adapted to press against the clamp ring.

14. The mixing device of claim 12, wherein a pipe head is further disposed at the beginning of the inner tube, a pipe shoulder is formed between the pipe head and the end surface of the beginning of the inner tube, the compression ring presses the inner tube through the pipe shoulder, and the pipe head extends into the inner cavity of the mixing device of the recirculated exhaust gas.

15. The recirculating exhaust mixing device of claim 9 wherein one of the inner sleeve and the outer sleeve is provided with a projection and the other is provided with a groove that engages the projection, the groove extending axially of the inner sleeve or the outer sleeve.

16. A diesel engine comprising a recirculating exhaust mixing device, wherein the recirculating exhaust mixing device is as claimed in any one of claims 1 to 15.

Technical Field

The invention relates to the field of circulating exhaust gas of diesel engines, in particular to a circulating exhaust gas mixing device and a diesel engine.

Background

In the process of recycling the circulating exhaust gas, the circulating exhaust gas is first mixed with fresh air, and then the mixed gas is introduced into each cylinder of the diesel engine. In order to mix the circulating exhaust gas and the fresh air uniformly, a person skilled in the art arranges a relatively complex cavity structure in the mixing chamber or arranges a relatively complex nozzle structure on the circulating exhaust gas pipeline. Although the above method can improve the uniformity of mixing, it can result in large pumping loss of the system.

Therefore, how to reduce the pumping loss of the system to the maximum extent on the basis of ensuring the uniformity of the mixed gas is a critical problem to be solved urgently by those skilled in the art.

Disclosure of Invention

The invention aims to provide a circulating exhaust gas mixing device which can ensure uniform mixing of mixed gas and reduce pumping loss of a system. In order to achieve the purpose, the invention provides the following technical scheme:

a circulating waste gas mixing device comprises a shell, wherein a partition plate is arranged in the shell, the partition plate divides an inner cavity of the shell into a mixing cavity and a pressure stabilizing cavity, and a through hole for communicating the mixing cavity with the pressure stabilizing cavity is formed in the partition plate;

be provided with circulation exhaust pipe and air pipe in the mixing chamber, circulation exhaust pipe with the air pipe is the straight tube, a plurality of circulation exhaust outlet have been arranged on the circulation exhaust pipe, a plurality of air outlet have been arranged on the air pipe, the steady voltage chamber communicates with the cylinder.

Preferably, a plurality of through holes are uniformly distributed on the partition plate.

Preferably, the mixing chamber is a rectangular chamber, the cross section of the partition is rectangular, and the contour edge of the partition is sequentially connected with the inner wall of the shell at the partition.

Preferably, the circulating exhaust gas pipe and the air pipe are arranged in parallel, and one of them is close to the partition plate with respect to the other.

Preferably, the inner wall of the shell is provided with two opposite slots, openings of the two slots are opposite, and two wide edge portions of the partition plate are respectively inserted into the two slots.

Preferably, a convex cavity protruding outwards is formed on the side plate which is in contact with one long side part of the partition plate, the convex cavity is communicated with the pressure stabilizing cavity, a port part of the convex cavity is provided with a flanging, and the flanging is connected with the cylinder.

Preferably, the side plate contacting the other long side portion of the partition plate is fixed by welding.

Preferably, the exhaust gas circulation device further comprises a circulating exhaust gas joint and an air joint which are arranged on the side part of the shell, the circulating exhaust gas pipe is communicated with the circulating exhaust gas joint, and the air pipe is communicated with the air joint.

Preferably, the circulating exhaust gas pipe is of a sleeve type structure and comprises an outer sleeve and an inner sleeve, circulating exhaust gas enters the inner sleeve, the outer sleeve is fixed relative to the shell, the tail ends of the outer sleeve and the inner sleeve are both blind ends, a pressure spring is arranged between the blind end of the outer sleeve and the blind end of the inner sleeve,

interior macropore and aperture are provided with along its axial interval on the interior sleeve pipe, be provided with a plurality of outer macropores along its axial on the outer tube, when the air input of circulation waste gas is little, the aperture on the interior sleeve pipe with outer macropore on the outer tube aligns, when the air input of circulation waste gas increases, interior sleeve pipe compression the pressure spring, interior macropore on the interior sleeve pipe gradually with outer macropore on the outer tube aligns.

Preferably, the inner sleeve is provided with a circle of the inner large holes and a circle of the small holes at intervals along the axial direction of the inner sleeve, and the outer sleeve is provided with a plurality of circles of the outer large holes along the axial direction of the outer sleeve.

Preferably, the outer large hole and the inner large hole are strip-shaped holes, and the small hole is a round hole.

Preferably, still include the clamp ring, the clamp ring receives the extrusion force that the circulation waste gas connects, and will the extrusion force is in the outer tube with on the terminal surface of interior sheathed tube top, the outer tube is compressed tightly on the casing, interior sleeve pipe extrusion the pressure spring, the circulation waste gas connect with the casing is connected, and with interior sleeve pipe intercommunication.

Preferably, the exhaust gas recirculation connector has a first flange, the housing has a second flange cooperating with the first flange, the clamp ring is located in a central hole of the second flange, and an end face of the first flange is used for pressing the clamp ring.

Preferably, the starting end of the inner sleeve is further provided with a pipe head, a pipe shoulder is formed between the pipe head and the end face of the starting end of the inner sleeve, the compression ring extrudes the inner sleeve through the pipe shoulder, and the pipe head extends into the inner cavity of the circulating waste gas connector.

Preferably, one of the inner sleeve and the outer sleeve is provided with a protrusion, and the other is provided with a groove matched with the protrusion, and the groove extends along the axial direction of the inner sleeve or the outer sleeve.

The invention also provides a diesel engine which comprises a circulating exhaust gas mixing device, wherein the circulating exhaust gas mixing device is any one of the circulating exhaust gas mixing devices.

According to the technical scheme, the inner cavity of the shell is divided into the mixing cavity and the pressure stabilizing cavity by the partition plate. In the mixing chamber, the circulating exhaust gas is emitted from a circulating exhaust gas outlet on the circulating exhaust gas pipe, and the fresh air is emitted from an air outlet on the air pipe. Due to the blocking effect of the partition plate, the mixed gas can generate pressure accumulation in the mixing cavity, so that the uniform mixing of the mixed gas is facilitated. In addition, the flow area of the circulating exhaust outlet can be set to be adjustable: when the air inflow of the circulating waste gas is large, the flow area of the circulating waste gas outlet is enlarged to reduce the interception loss, so that the pumping pressure loss is reduced; when the air inflow of the circulating waste gas is small, the flow area of the circulating waste gas outlet is reduced to improve the flow rate of the circulating waste gas, so that uniform mixing is facilitated.

Drawings

In order to more clearly illustrate the solution of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the description below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without inventive efforts.

Fig. 1 is a sectional view of a circulating exhaust gas mixing apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a circulating exhaust gas mixing device according to an embodiment of the present invention;

FIG. 3 is another cross-sectional view of a recirculating exhaust mixing device in accordance with one embodiment of the present invention;

FIG. 4 is a schematic view of another angle of FIG. 2;

FIG. 5 is a schematic view of the outer and inner sleeves in conjunction with a larger flow of recirculated exhaust gas provided by an embodiment of the present invention;

FIG. 6 is a schematic view of the outer and inner sleeves in conjunction with a relatively low flow rate of recirculated exhaust gas according to an embodiment of the present invention;

fig. 7 is a schematic structural view illustrating the inner sleeve and the outer sleeve being compressed by the compression ring according to an embodiment of the present invention.

Wherein, 1 is an inner sleeve, 2 is an air pipe, 3 is a clapboard, 4 is a circulating waste gas joint, 5 is an air joint, 6 is a shell, 7 is a flanging, 8 is a side plate, 9 is a pressure spring, 10 is a pipe head, 11 is an outer sleeve, 12 is an inner big hole, 13 is an outer big hole, 14 is a small hole, and 15 is a compression ring.

Detailed Description

The invention discloses a circulating waste gas mixing device which can ensure that mixed gas is uniformly mixed and can reduce pumping loss of a system.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

In an embodiment of the present invention, the circulating exhaust gas mixing device includes a housing 6, a partition plate 3, a circulating exhaust gas pipe, and an air pipe 2. The partition plate 3 divides the inner cavity of the housing 6 into a mixing chamber and a pressure stabilizing chamber. The partition plate 3 is provided with a through hole which is used for communicating the mixing cavity and the pressure stabilizing cavity.

A circulating exhaust gas pipe and an air pipe 2 are arranged in the mixing cavity. And a plurality of circulating exhaust outlets are arranged on the circulating exhaust pipe. A plurality of air outlet holes are arranged on the air pipe 2. In order to improve the uniformity of mixing, a plurality of circulating exhaust outlets may be evenly distributed on the circulating exhaust pipe, and a plurality of air outlets may be evenly distributed on the air pipe 2.

In the mixing chamber, the circulating exhaust gas is emitted from a circulating exhaust gas outlet on the circulating exhaust gas pipe, and the fresh air is emitted from an air outlet on the air pipe. Due to the blocking effect of the partition plate, the mixed gas can generate pressure accumulation in the mixing cavity, so that the mixing uniformity of the mixed gas is facilitated. The mixed gas can enter the pressure stabilizing cavity through the through holes in the partition plate after being fully mixed in the mixing cavity, and then enters each cylinder.

Further, both the circulation-restricted exhaust gas pipe and the air pipe 2 are straight pipes. The straight pipe-shaped circulating exhaust gas pipe and the air pipe 2 have a simple structure, so that the resistance of the circulating exhaust gas and the fresh air is small in the process of respectively radiating from the circulating exhaust gas outlet and the air outlet, and the pumping pressure loss can be reduced.

In conclusion, the uniform distribution of the circulating waste gas outlet and the air outlet and the relatively closed mixing cavity can ensure the uniformity of mixing of the circulating waste gas and the fresh air. While the straight pipe-shaped circulating exhaust gas pipe and the air pipe 2 can significantly reduce pumping loss. Therefore, the circulating waste gas mixing device can ensure that the mixed gas is uniformly mixed and can reduce the pumping loss of the system.

In the prior art, the fresh air and the circulating exhaust gas flowing out of the air pipe 2 and the circulating exhaust gas pipe are mixed in the mixing chamber and then enter the intake pipe and then enter each cylinder. However, the air inlet of the intake pipe is usually disposed at one end of the intake pipe or at the middle of the intake pipe, so that the mixture gas entering the intake pipe has a bias, which eventually results in non-uniform gas amount entering each cylinder. In addition, the mixing chamber in the prior art is usually provided with a right-angle structure, and the mixed gas can be deflected when passing through the right-angle structure. The mixed gas concentration near the inner right angle is large, and the mixed gas concentration near the outer right angle is small, so that the mixed gas bias in the intake pipe is increased. The pressure stabilizing cavity is communicated with each cylinder. In the invention, a plurality of through holes are uniformly distributed on the partition plate 3, instead of arranging an air inlet at a certain part of an air inlet pipe as in the prior art, and the mixed gas in the invention is uniformly mixed in the mixing cavity, so that the mixed gas in the invention can uniformly enter the pressure stabilizing cavity in the length direction of the partition plate 3, the amount of the mixed gas at each position of the pressure stabilizing cavity is equal, the bias of the mixed gas is obviously weakened, and the amount of the gas entering each cylinder is ensured to be basically equal.

Further, the mixing chamber is provided as a rectangular parallelepiped chamber, and correspondingly, the cross section of the partition plate 3 is rectangular. The structure can be simplified and the production and the manufacture are convenient. In addition, the contour edge portion defining the partition 3 is in sequential contact with the inner wall of the housing 6 at the partition 3. So set up, can improve the closure of hybrid chamber to do benefit to the mist and produce the pressure accumulation in the hybrid chamber.

Further, the circulating exhaust gas pipe and the air pipe 2 are arranged in parallel, one of which is close to the partition plate 3 with respect to the other. As shown in fig. 1, the circulating exhaust gas pipe is located above the air pipe 2. So set up, can make circulation exhaust gas mixing arrangement's structure compacter.

In the manufacturing process, in order to facilitate the installation and positioning of the partition board 3, a slot may be provided in advance on the inner wall of the housing 6. The two slots are oppositely arranged, and the openings of the slots are opposite. The two wide side portions of the partition plate 3 can be inserted into the two insertion grooves from above, respectively.

The partition 3 has two long side portions. The two long side portions are in contact with the two side plates, respectively. A convex cavity protruding outwards is formed on the side plate contacting with one long side part of the partition plate 3, and the convex cavity is communicated with the pressure stabilizing cavity. The port part of the convex cavity is provided with a flange 7, and the flange 7 is provided with a bolt hole. And the air inlet port of the air cylinder is provided with a matching hole matched with the bolt hole. The bolt passes through the bolt hole and the matching hole so as to realize the connection of the circulating exhaust gas mixing device and the cylinder.

Further, the side plate 8, which is in contact with the other long side portion of the partition plate 3, is fixed to the main body portion of the case 6 by welding. The welding ensures the sealing performance of the housing 6.

Further, for convenience of use, a circulation exhaust joint 4 and an air joint 5 are provided at the side of the housing 6. The circulating waste gas pipe is communicated with a circulating waste gas joint 4, and an air joint 5 is communicated with the air pipe 2.

In one embodiment of the invention, the circulating exhaust gas pipe is provided as a sleeve-type structure. The circulating exhaust gas pipe comprises an outer sleeve 11 and an inner sleeve 1. The inner tube 1 is disposed inside the outer tube 11. The recirculated exhaust gas enters the inner jacket tube 1. The outer sleeve 11 is stationary relative to the housing 6. The ends of the outer sleeve 11 and the inner sleeve 1 are blind ends. The end of the outer sleeve 11 is the end of the outer sleeve 11 far away from the circulating waste gas joint 4. The end of the inner sleeve 1 is the end of the inner sleeve 1 far away from the circulating exhaust gas joint 4. A pressure spring 9 is arranged between the blind end of the outer sleeve 11 and the blind end of the inner sleeve 1. The compression spring 9 is pressed by the blind end of the inner sleeve 1 and the blind end of the outer sleeve 11.

Further, the inner tube 1 is provided with inner large holes 12 and small holes 14 at intervals along the axial direction of the inner tube 1. I.e., along the axial direction of the inner sleeve 1, there are arranged an inner large hole 12, an outer small hole 14, and so on in this order. A plurality of outer large holes 13 are provided in the outer sleeve 11 in the axial direction. When the air inflow of the circulating exhaust gas is small, please refer to fig. 6, the small holes 14 on the inner sleeve 1 are aligned with the large outer holes 13 on the outer sleeve 11. I.e. the small holes 14 and the outer large holes 13 now constitute the recycling exhaust outlet. The circulation area of the circulation waste gas outlet at the moment is smaller, so that the flow velocity of the circulation waste gas is forced to be increased, and the uniform mixing with the fresh air is facilitated.

When the air inflow of the circulating exhaust gas is large, please refer to fig. 7, the air inflow pressure of the circulating exhaust gas in the inner sleeve 1 is large, and the air inflow pressure of the circulating exhaust gas acts on the blind end of the inner sleeve 1, so that the inner sleeve 1 extrudes the compression spring 9, and then the inner sleeve 1 axially moves relative to the outer sleeve 11. During the movement, the inner large hole 12 on the inner sleeve 1 is gradually aligned with the outer large hole 13 on the outer sleeve 11, and the inner sleeve 1 does not move after the inner large hole 12 is aligned with the outer large hole 13. The inner large hole 12 and the outer large hole 13 form a circulation exhaust outlet, and the circulation exhaust outlet has a large flow area. Namely, when the air inflow of the circulating waste gas is large, the flow area of the circulating waste gas outlet is increased, so that the circulating waste gas is discharged favorably, and the pumping pressure loss is reduced.

Further, the outer large hole 13 and the inner large hole 12 are both configured as strip-shaped holes. Which extends in the axial direction of the outer jacket tube 11 or the inner jacket tube 1. The small hole 14 on the outer sleeve 11 is set as a small circular hole. Namely, when the flow of the circulating waste gas is small, the round hole on the inner sleeve 1 is aligned with the strip-shaped hole on the outer sleeve 11 to form a circulating waste gas outlet with a small flow area. When the flow of the circulating waste gas is large, the strip-shaped holes in the inner sleeve 1 are aligned with the strip-shaped holes in the outer sleeve 11 to form a circulating waste gas outlet with a large flow area.

Further, a compression ring 15 is included. The pressure ring 15 is subjected to the pressure of the exhaust gas recirculation connection 4, after which the pressure ring 15 exerts a pressure on the end faces of the beginning of the outer jacket tube 11 and the inner jacket tube 1. The beginning of the outer sleeve 11 is the end of the outer sleeve 11 that is distal from the blind end of the outer sleeve 11. The starting end of the inner jacket tube 1 is the end of the inner jacket tube 1 remote from the blind end of the inner jacket tube 1. The outer jacket tube 11 is pressed against the housing by a pressing ring 15. The inner sleeve 1 is subjected to the extrusion action of the compression ring 15 and then extrudes the compression spring 9, so that pre-tightening force is generated, and the compression spring 9 can be stably extruded by the subsequent inner sleeve 1. In addition, a circulating exhaust gas connection 4 is connected to the housing 6, and the circulating exhaust gas connection 4 communicates with the inner jacket tube 1. I.e. the circulating exhaust gas passes through the circulating exhaust gas connection 4 and enters the inner jacket tube 1.

Further, in order to ensure the stability of the compression spring 9, an inner protrusion is provided on the blind end of the inner sleeve 1, and an outer protrusion is provided on the blind end of the outer sleeve 11. The two ends of the pressure spring 9 are sleeved on the inner convex part and the outer convex part, so that the pressure spring 9 is favorably and stably compressed along the axial direction.

Further, the circulating exhaust joint 4 is connected with the housing 6 in the following manner: a first flange (not shown) is provided on the recirculating exhaust gas connection 4, and a second flange is provided on the housing 6. The first flange plate is matched with the second flange plate. The first flange plate and the second flange plate are locked by the locking bolts, and the connection of the circulating waste gas joint 4 and the shell 6 can be realized. The clamp ring 15 is located in the central bore of the second flange, and the end face of the first flange is used to compress the clamp ring 15.

Further, a tip 10 is provided at the beginning of the inner casing 1, the diameter of the tip 10 being smaller than the diameter of the inner casing 1. A shoulder (not shown) is formed between the tip 10 and the end face of the initial end of the inner jacket tube 1. A portion of the clamp ring 15 acts on the tube shoulder. I.e. the clamping ring 15 presses the inner jacket tube 1 via the tube shoulder. The arrangement of the tube shoulder increases the contact area of the compression ring 15 and the inner sleeve 1. In addition, the pipe head 10 projects into the interior of the waste gas recirculation connection 4.

Further, a circle of large inner holes 12 and a circle of small inner holes 14 are arranged on the inner sleeve 1 at intervals along the axial direction of the inner sleeve 1. Namely, a circle of large inner holes 12, a circle of small inner holes 14, and the like are arranged on the inner sleeve 1. Correspondingly, the outer sleeve 11 is provided with a plurality of circles of outer large holes 13 along the axial direction of the outer sleeve 11. The number of the large holes 12 in each circle, the number of the small holes 14 in each circle and the number of the large holes 13 outside each circle are all equal. I.e. circumferentially, each inner large hole 12, each small hole 14 and each outer large hole 13 correspond.

In order to prevent the inner sleeve 1 from rotating in the circumferential direction relative to the outer sleeve 11, in a particular embodiment of the invention, a projection (not shown) is provided on one of the outer sleeve 11 and the inner sleeve 1 and a recess (not shown) is provided on the other for cooperating with the projection. And the grooves extend in the axial direction of the inner sleeve 1 or the outer sleeve 11. That is, the inner sleeve 1 is axially movable relative to the outer sleeve 11, but is not circumferentially rotatable relative to the outer sleeve 11. Specifically, a projection may be provided on the outer wall of the inner sleeve 1 and a groove may be provided on the inner wall of the outer sleeve 11.

In the process of installing the circulating exhaust gas pipe, the pressure spring 9 is placed at the blind end of the outer sleeve 11, the inner sleeve 1 extends into the inner sleeve 1, the blind end of the inner sleeve 1 extrudes the pressure spring 9, meanwhile, the protrusion on the inner sleeve 1 is matched in the groove of the outer sleeve 11, then, the compression ring 15 is sleeved at the end face of the starting end of the outer sleeve 11, then, the outer sleeve 11 and the inner sleeve 1 are inserted into the shell 6, then, the end face of the first flange of the circulating exhaust gas joint 4 is attached to the end face of the second flange of the shell 6, and meanwhile, the first flange extrudes the compression ring 15. Finally, the first flange plate and the second flange plate are locked through bolts, and meanwhile, the small holes 14 in the inner sleeve 1 are aligned with the large outer holes 13 in the outer sleeve 11.

It should be noted that, when designing the axial distance between the inner large hole 12 and the small hole 14, it is ensured that the inner large hole 12 is already overlapped with the outer large hole 13 before the small hole 14 completely staggers the outer large hole 13. Likewise, it is also ensured that the small holes 14 already coincide with the outer large holes 13 before the inner large holes 12 are completely staggered with respect to the outer large holes 13. Thus, the circulation exhaust gas outlet can be prevented from being clogged while the inner sleeve 1 is axially moved.

In the process of installing the air pipe 2, a third flange plate is welded on the air joint 5, and a fourth flange plate matched with the third flange plate is arranged on the shell 6. The air joint 5 is welded to the air tube 1. Then the end of the air tube 2 remote from the air connection 5 is inserted into the housing 6, after which the air tube 2 is moved towards the inside of the housing 6 until the third flange on the air connection 5 comes into contact with the fourth flange on the housing 6, after which the third flange and the fourth flange are fastened by means of bolts.

In order to reduce the processing difficulty, the length of the air tube 2 is designed to be smaller than the length of the housing 6, so that the problem that the end of the air tube 2 is pressed against the inner wall of the housing 6 and the third flange on the air joint 5 cannot be contacted with the fourth flange can be avoided.

In summary, the flow paths of the circulating exhaust gas and the fresh air are as follows: the circulating exhaust gas enters the inner jacket tube 1 via a circulating exhaust gas connection 4. If the air inflow of the circulating exhaust gas is small, the circulating exhaust gas in the inner sleeve 1 flows out through the small holes 14 on the inner sleeve 1 and the large outer holes 13 on the outer sleeve 11; if the intake of the circulating exhaust gas is large, the circulating exhaust gas in the inner sleeve 1 flows out through the inner large holes 12 on the inner sleeve 1 and the outer large holes 13 on the outer sleeve 11.

Fresh air enters the air tube 2 through the air connection 5 and is then distributed into the mixing chamber through a plurality of air outlet holes evenly distributed in the air tube 2. Because the mixing cavity is relatively closed, the mixed gas forms pressure accumulation in the mixing cavity, and the pressure accumulation can accelerate the flow of the gas, so that the mixed gas is mixed more uniformly. Then the uniformly mixed gas uniformly enters the pressure stabilizing cavity in the length direction of the shell 6 through the through holes uniformly distributed on the partition plate 3. And then the mixed gas in the pressure stabilizing cavity enters each cylinder.

The invention also discloses a diesel engine which comprises the circulating exhaust gas mixing device, particularly, the circulating exhaust gas mixing device is any one of the circulating exhaust gas mixing devices, the circulating exhaust gas mixing device has the advantages, and the diesel engine with the circulating exhaust gas mixing device also has the advantages, so that the description is omitted.

Finally, it should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.