WO2020192043A1

WO2020192043A1 - Three-way cylinder head cooling structure having partially tapered exhaust channel

Info

Publication number: WO2020192043A1
Application number: PCT/CN2019/106534
Authority: WO
Inventors: 张雷; 余晓强; 李壮; 石峰; 魏威
Original assignee: 广西玉柴机器股份有限公司
Priority date: 2019-03-28
Filing date: 2019-09-18
Publication date: 2020-10-01
Also published as: CN109915275A

Abstract

A three-way cylinder head cooling structure having a partially tapered exhaust channel comprises a ridge region water channel (1) between a gas inlet channel (7) and an exhaust channel (6) on a cylinder head, a fuel injector mounting protection sleeve (4), a main water injection channel (2) communicating with the ridge region water channel, and an upper water hole (3) extending upwards from the bottom of the cylinder head and connected to the main water injection channel. A tapered portion (5) is provided on the exhaust channel, and extends inwards from the bottom of the ridge region water channel. The ridge region water channel extends to the outside of the tapered portion so as to form a cooling channel (8). The cooling channel and the tapered portion are provided at a junction between the exhaust channel and the fuel injector mounting protection sleeve. A bypass water channel (9) extends upwards from the upper water hole. The bypass water channel communicates with an upper portion water channel (10) above the main water injection channel. An inner diameter of the main water injection channel is greater than that of the bypass water channel. The invention solves the problem of heat accumulation at a junction between a fuel injector mounting hole boss and the exhaust channel, and solves the problem in which water of a water injection channel of a ridge region can only flow in one direction, thereby allowing portions other than the ridge region to be evenly cooled.

Description

Three-way cylinder head cooling structure with partial necking of exhaust duct

Technical field

The invention relates to the field of engine cylinder heads, in particular to a three-way cylinder head cooling structure with a partial necking of an exhaust duct.

Background technique

Engine supercharging technology has been widely used in engines. The technical route of supercharging technology can greatly increase the power per liter, the strengthening of the engine will be further improved, the explosion pressure and combustion temperature will be greatly increased, and the thermal load on the cylinder head will increase. The cooling system puts forward higher requirements.

In the prior art, the fuel injector mounting hole boss is stuck with the exhaust duct, and there is a lot of local metal accumulation in the stuck part. For example, Chinese patent CN104295394A discloses a diesel engine cylinder head, including: a cylinder head body and the cylinder head In the water cavity in the main body, there is an upper water hole communicating with the water cavity under the cylinder head exhaust duct of the cylinder head body, and a deflector facing the injector installation hole is arranged on the right side of the exhaust duct wall of the cylinder head body; A water passage outside the exhaust duct is opened between the exhaust pipe mounting surface of the cylinder head body and the wall of the push rod hole. The water passage outside the exhaust duct is a cooling channel outside the exhaust duct, which is directly connected to the water outlet and at the same time partially A bridging channel is provided to isolate the exhaust duct wall of the cylinder head body from the exhaust pipe mounting screw boss. As can be seen from Figure 2 of the document, the diesel engine cylinder head separates the exhaust duct wall and the exhaust pipe screw hole boss, which effectively reduces the temperature of the exhaust pipe mounting surface and bolts, and ensures the cooling effect. However, this structure has serious metal accumulation at the junction of the injector mounting hole boss and the exhaust duct, which is likely to cause heat accumulation and poor local cooling, and there is a risk of thermal fatigue damage; and the cooling passage between the exhaust duct and the injector mounting hole is relatively short Narrow, the cooling channel is higher than the cooling channel in the nose bridge, blocking the flow of cooling liquid in the nose bridge, the cooling effect of the nose bridge and the fire surface is not good, the cylinder head is prone to thermal fatigue damage and the valve seat is prone to abnormal wear.

In addition, in the prior art, by adding a water jet in the nose bridge area to increase the amount of cooling water in the nose bridge area to improve the cooling effect, the prior art only introduces cooling water from the jet water channel to the nose bridge area, although it effectively cools the nose bridge. Area and fire surface, but the directivity of the cooling water is too strong, the position outside the nose bridge area is not well cooled, the position above the main injection channel is not cooled uniformly, the cylinder head is prone to local heat accumulation, and the cylinder head is prone to deformation and cracking .

Summary of the invention

The present invention provides a three-way cylinder head cooling structure with a partially necked exhaust duct, which solves the problem of heat accumulation at the junction of the injector mounting hole boss and the exhaust duct, improves the cooling effect of the nose bridge area, and improves the performance of the exhaust gas supercharger Energy utilization rate of exhaust gas; solve the problem of single directionality of water jet in the nose bridge area, and make the nose bridge area and its surrounding parts cool evenly.

The technical scheme of the present invention is as follows:

A three-way cylinder head cooling structure with a partially necked exhaust duct, comprising a nose bridge water channel between an intake duct on the cylinder head and the exhaust duct, and a fuel injector installation sheath, which is connected to the nose bridge water channel The main injection channel, the upper water hole connected to the main injection channel set up from the bottom of the cylinder head, the exhaust channel is provided with a constriction inwardly at the bottom of the nose bridge water channel, and the nose bridge water channel is along the The outer side of the necked part extends to form a cooling channel, and the cooling channel and the necked part are arranged at the junction of the exhaust duct and the fuel injector installation sheath. This technical solution removes the metal accumulated at the junction of the injector installation sheath and the exhaust duct. The design of the necking part makes the cooling channel replace the metal accumulation position, eliminates the local heat accumulation and removes The blocking of the water passage in the nose bridge area improves the cooling effect of the nose bridge area and the fire surface, avoiding thermal fatigue damage of the cylinder head and abnormal wear of the valve seat; in addition, the exhaust pipe is provided with a partial contraction to the inside, and the flow interface is locally reduced, and the exhaust The flow rate is increased, the return vortex is reduced, the flow coefficient of the exhaust duct is increased, and the exhaust gas energy utilization rate of the exhaust gas turbocharger is improved.

The upper water hole is provided with a bypass water channel extending upward, the bypass water channel is communicated with the upper water channel above the main water jet, and the inner diameter of the main water jet is larger than the inner diameter of the bypass water channel; The hole, the bypass water channel and the main injection water channel are in a three-way structure. The cooling water mainly circulates through the upper water hole to the main injection water channel and enters the nose bridge water channel, while part of the cooling water flow enters the bypass The water channel finally enters the water channel above the cylinder head, which realizes the diversion of cooling water and reduces the unity of the cooling direction of the traditional water jet cooling method in the nose bridge. The inner diameter of the main water jet is larger than the inner diameter of the bypass water channel to ensure that all The water flow of the main water jet is greater than the water flow of the bypass water channel, which not only retains the function of the water jet to rapidly cool the nose bridge area, but also ensures that the parts outside the nose bridge area are also cooled. The water channel above the main water jet The cooling is uniform, local heat accumulation is avoided, and the reliability of the cylinder head is improved.

Preferably, the height of the cooling channel and the bottom of the main water injection channel are level, the main water injection channel can enter the cooling channel more smoothly, and the cooling efficiency is further improved.

Preferably, the fuel injector installation sheath (4) is integrally formed with the cylinder head, which is formed by integral casting, which simplifies the installation process and saves costs.

Preferably, the arc transitional connection between the main water jet and the water channel in the nose bridge area is beneficial to reduce the flow resistance of the cooling water, the flow speed is fast, and the cooling efficiency is improved.

The upper water hole and the main water injection channel are integrally cast and formed, and the bypass water channel is a drilled forming hole and is processed by a drilling method. The axis of the upper water hole and the axis of the bypass water channel are both perpendicular to the bottom surface of the cylinder head, the cooling water flow resistance is small, and the drilling location and installation of the bypass water channel are facilitated, thereby reducing the cost.

The beneficial effects of the present invention:

1. The metal accumulated at the junction of the injector installation sheath and the exhaust duct is removed, the local heat accumulation is eliminated, the cooling effect of the nose bridge area and the fire surface is improved, and the thermal fatigue damage of the cylinder head and abnormal valve seat ring are avoided Wear.

2. A partial shrinkage is set to the inner side of the exhaust duct, the flow interface is locally reduced, the exhaust flow rate is increased, the return vortex is reduced, the flow coefficient of the exhaust duct is improved, and the exhaust energy utilization rate of the exhaust gas turbocharger is improved.

3. The bypass water channel partially diverts the cooling water of the main injection channel, which not only retains the function of the injection channel to quickly cool the nose area, but also ensures the cooling above the cylinder head. The cylinder head is cooled evenly, which improves the reliability of the cylinder head.

Description of the drawings

Fig. 1 is a schematic cross-sectional view of a cylinder head according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of the cross-sectional structure in the direction B-B in Fig. 1.

Fig. 3 is a schematic view of the cross-sectional structure in the direction A-A in Fig. 1.

Fig. 4 is a schematic diagram of the outline of an exhaust duct according to an embodiment of the present invention.

In the picture: 1. Water channel in the bridge of the nose; 2. Main injection channel; 3. Water hole; 4. Injector installation sheath; 5. Neck part; 6. Exhaust duct; 7. Inlet duct; 8. Cooling channel; 9. Bypass water channel; 10. Upper water channel.

detailed description

The present invention will be further described below in conjunction with specific embodiments and drawings:

As shown in Figures 1 to 2, this embodiment is a two-valve structure engine, a three-way cylinder head cooling structure with a partially narrowed exhaust port, including one of the intake port 7 and the exhaust port 6 on the cylinder head. Nose bridge area water channel 1, injector installation sheath 4, injector installation sheath 4 is used to install the injector, the main injection water channel 2 connected with the nose bridge area water channel 1 is set up from the bottom of the cylinder head The upper water hole 3 connected to the main jetting channel 2, and the exhaust channel is provided with a constriction 5 inwardly at the bottom position of the nasal bridge area water channel 1, and the nasal bridge area water channel 1 extends along the constriction 5 The outer side extends to form a cooling channel 8. The nose bridge area water channel 1 extends downward to the outer side of the necked portion 5 to form a cooling channel 8. The cooling channel 8 and the necked portion 5 are arranged in the exhaust channel 6 The junction with the injector installation sheath 4;

As shown in FIG. 3, the upper water hole 3 is provided with a bypass water channel 9 extending upward, and the bypass water channel 9 is connected to the upper water channel 10 above the main water injection channel 2, and the inner diameter of the main water injection channel 2 is larger than The inner diameter of the bypass water channel 9, the upper water hole 3, the bypass water channel 9 and the main injection channel 2 are in a three-way structure with a "T"-shaped structure.

As shown in Figure 3, the height of the bottom of the cooling channel 8 is flush with the height of the bottom of the main water jet 2;

As shown in Figure 2, the injector mounting sheath 4 is integrally formed with the cylinder head;

As shown in Figure 3, the main water jet 2 and the nose bridge water channel 1 are connected in a circular arc transition.

The upper water hole 3 and the main water injection channel 2 are integrally cast and formed, and the bypass water channel 9 is a drilled shaped hole and is processed by a drilling method.

The working principle of the present invention is as follows:

Figures 1 and 3 show the flow direction of the cooling water in the working state of the present invention: the upper water hole 3, the bypass water channel 9 and the main water jet 2 are in a three-way structure, and the cooling water passes through the water The hole 3 flows upwards and then divides into two water paths: the main injection water path and the bypass water path. The main injection water path passes through the main injection water path 2 and flows into the nose bridge water path 1, and then sprays from the main injection water path 2 to the cooling channel 8 and the nose bridge. District waterway 1, cooling channel 8 cools the junction of the injector installation sheath 4 and exhaust duct 6, and the nose bridge area waterway 1 cools the nose bridge area and the fire surface; the bypass waterway enters after passing through the bypass waterway 9 To the upper water channel 10 above the main injection channel 2, and then disperse and flow to other water channels for cooling, so the area outside the nose bridge area is also cooled. By adopting this structure, the nose bridge area, the fire surface and the upper water channel 10 above the main injection channel 2 can be cooled, the cooling effect of the cylinder head is uniform, and the thermal deformation or cracking of the cylinder head can be avoided.

Figure 4 shows the outline of the exhaust duct 6 and the flow direction of the cooling water. Because the exhaust duct 6 is provided with the necked portion 5, the corresponding cross-sectional area at this position is reduced, and the exhaust flow rate is increased. , Improve the exhaust flow coefficient and improve the exhaust gas energy utilization rate of the exhaust gas turbocharger.

Claims

A three-way cylinder head cooling structure with a partially narrowed exhaust duct, which includes a water duct (1) in the nose bridge area between an intake duct (7) and an exhaust duct (6) on the cylinder head. The sleeve (4), the main injection channel (2) connected with the water channel (1) of the nose bridge area, and the upper water hole (3) connected with the main injection channel (2) set up from the bottom of the cylinder head, is characterized by: At the junction of the exhaust passage (6) and the injector installation sheath (4), the exhaust passage (6) is provided with a constriction (5) inwardly, and the nose bridge area water passage (1) A cooling channel (8) is formed along the outer side of the necking part (5); the upper water hole (3) is provided with a bypass water channel (9) extending upward, and the bypass water channel (9) is connected to the main The upper water channel (10) above the water jet (2) is connected, and the inner diameter of the main water jet (2) is larger than the inner diameter of the bypass water channel (9).
A three-way cylinder head cooling structure with a partially necked exhaust duct according to claim 1, wherein the cooling channel (8) is at the same height as the bottom of the main injection channel (2).
A three-way cylinder head cooling structure with a partially necked exhaust duct according to claim 1 or 2, characterized in that the injector mounting sheath (4) is integrally formed with the cylinder head.
A three-way cylinder head cooling structure with a partially narrowed exhaust duct according to claim 1 or 2, characterized in that: the main injection water channel (2) and the nose bridge water channel (1) arc transition connection.
A three-way cylinder head cooling structure with a partially necked exhaust duct according to claim 1 or 2, characterized in that: the upper water hole (3) and the main injection channel (2) are integrally cast and formed , The bypass water channel (9) is a drilled shaped hole.