Novel high-pressure common rail diesel engine cylinder cover

Abstract

The utility model discloses a novel high-pressure common-rail diesel engine cylinder cover, which belongs to the technical field of diesel engine cylinder covers and comprises a cylinder cover body, an exhaust passage with a forked 'Y'-shaped structure, an air inlet passage with a double-air-passage structure, an oil sprayer hole and a cooling water passage, and the exhaust passage, the air inlet passage, the oil sprayer hole and the cooling water passage are arranged in the cylinder cover body. A single exhaust outlet of the exhaust passage is formed in the exhaust end face of the lower end of the cylinder cover body, two exhaust inlets of the exhaust passage are formed in the bottom face of the cylinder cover body, and three cooling water passage process holes of the cooling water passage are formed in the lower left corner and the left end face and the right end face of the top face of the cylinder cover body respectively. A concave cavity is formed in the joint of the top face of the cylinder cover body and the exhaust end face of the cylinder cover body, a technological boss flush with the exhaust end face is integrally formed in the concave cavity, and a cooling water channel technological hole in the lower left corner of the top face of the cylinder cover body is formed in the concave cavity on the left side of the technological boss. The sealing performance of the exhaust face can be effectively improved, meanwhile, the exhaust efficiency of the exhaust pipe can be effectively improved, and the exhaust performance of the whole machine is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of diesel engine cylinder covers, and in particular relates to a novel high-pressure common rail diesel engine cylinder cover. Background Art

[0002] With the advancement of science and technology, the high-pressure common rail system has become a key direction for the development of diesel engine technology due to its excellent power, economy and environmental performance. The cylinder head is one of the key core parts of the high-pressure common rail diesel engine and an important part of the diesel engine combustion chamber. The basic structure of the cylinder head mainly includes the cylinder head body, spiral dual intake ducts, two-in-one gradient exhaust ducts and complex cooling water channels. Figure 1 As shown, Chinese utility model patent document CN221220644U discloses a water-cooled diesel engine cylinder head, which mainly includes a monolithic cylinder head body 1 and a forked "Y"-shaped exhaust duct, a dual-air duct structure intake duct, an injector hole and a cooling water duct arranged inside the cylinder head. The single exhaust outlet 2 of the exhaust duct is arranged on the exhaust end face 3 at the lower end of the cylinder head, and the two inlets of the intake duct are arranged side by side on the intake end face at the upper end of the cylinder head. The two inlets of the exhaust duct are parallel to the two outlets of the intake duct and are arranged side by side on the fire surface of the bottom surface of the cylinder head; the injector hole is arranged at the center position of the four air duct openings on the fire surface of the cylinder head and penetrates to the valve chamber body sealing surface on the top surface of the cylinder head; the cooling water channel is wrapped around the intake duct and the exhaust duct, wherein the three cooling water channel process holes 4 of the cooling water channel are respectively opened on the left and right end surfaces of the cylinder head and the lower left corner of the top surface, and the cooling water channel process hole 4 at the lower left corner of the top surface of the cylinder head is arranged above the exhaust end face 3 of the cylinder head.

[0003] While the aforementioned water-cooled diesel engine cylinder head meets the requirements of high-pressure common rail diesel engines for greater power, higher fuel injection pressure, cleaner emissions, and improved braking capabilities, it also has some drawbacks. Due to the limited location of the three cooling water channel process holes, it is difficult to completely clean the residual sand remaining in the narrow areas of the cylinder head's built-in cooling water channels after casting. This residual sand, as it circulates with the coolant through the diesel engine's cooling system, can damage various water channel sealing components. Furthermore, the cylinder head's exhaust end face is relatively small, resulting in a smaller sealing surface between it and the exhaust pipe, which can easily lead to air and oil leaks from the exhaust pipe. Furthermore, the exhaust efficiency of existing diesel engine cylinder heads generally has significant room for improvement, which is of great significance for improving the overall engine's emission performance.

[0004] Therefore, there is a need for a new high-pressure common rail diesel engine cylinder head that has good exhaust surface sealing, is conducive to cleaning residual sand in the cooling water channel, and can improve exhaust performance. Utility Model Content

[0005] The purpose of the utility model is to provide a new type of high-pressure common rail diesel engine cylinder head, which can effectively improve the sealing of the exhaust surface, and at the same time is conducive to convenient and quick cleaning of residual sand in the cooling water channel after casting, effectively preventing the residual sand from damaging various water channel sealing components when circulating with the coolant in the diesel engine cooling system, and at the same time can effectively improve the exhaust efficiency of the exhaust pipe and improve the emission performance of the entire machine.

[0006] In order to achieve the above purpose, the technical solution adopted by the present utility model is:

[0007] A new type of high-pressure common rail diesel engine cylinder head includes a cylinder head body and a forked "Y"-shaped exhaust duct, a dual-air duct intake duct, an injector hole and a cooling water duct arranged inside the cylinder head body. The single exhaust outlet of the exhaust duct is arranged on the exhaust end face at the lower end of the cylinder head body, and its two exhaust inlets are arranged on the bottom face of the cylinder head body. The cooling water duct is wrapped around the intake duct and the exhaust duct. The three cooling water channel process holes of the cooling water channel are respectively opened at the lower left corner of the top face of the cylinder head body and the left and right end faces thereof. A concave cavity is opened at the junction of the top face of the cylinder head body and its exhaust end face, and a process boss flush with the exhaust end face is integrally formed in the concave cavity. The cooling water channel process hole at the lower left corner of the top face of the cylinder head body is arranged in the concave cavity on the left side of the process boss.

[0008] A further improvement of the technical solution of the present utility model is that a sand cleaning hole communicating with the cooling water channel is opened on the side wall of the cylinder head body on the right side of the exhaust end face thereof.

[0009] A further improvement of the technical solution of the present utility model is that the exhaust duct is an integrally formed structure, which includes branch air ducts respectively connected to the two exhaust inlets and a main air duct connected to the single exhaust outlet at one end and the two branch air ducts at the other end, and the two branch air ducts intersect with the end portion connected to one end of the main air duct.

[0010] A further improvement of the technical solution of the present invention is that: in the inner cavity of the exhaust duct, a diversion ridge extending to the main air duct is integrally formed at the lower part of the intersection of the two branch air ducts.

[0011] A further improvement of the technical solution of the present invention is that the diverter ridge is a ridge-like structure for guiding airflow, which is arranged symmetrically with the intersection line of the two branch airways as the axis, and the width of the diverter ridge increases from top to bottom along the length direction of the intersection line.

[0012] A further improvement of the technical solution of the present invention is that the highest point of the diverter ridge is arranged close to the main airway, and the height of the diverter ridge decreases from its highest point to its upper and lower ends.

[0013] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is:

[0014] The utility model discloses a new high-pressure common rail diesel engine cylinder head, which can effectively improve the sealing performance of the exhaust surface, and is conducive to conveniently and quickly cleaning the residual sand in the cooling water channel after casting, effectively preventing the residual sand from damaging various water channel sealing components when the coolant circulates in the diesel engine cooling system, and at the same time can effectively improve the exhaust efficiency of the exhaust pipe and improve the emission performance of the entire machine.

[0015] The utility model adopts a concave cavity at the junction of the top surface of the cylinder head body and its exhaust end surface, and a process boss flush with the exhaust end surface is integrally formed in the concave cavity, thereby effectively increasing the area of ​​the exhaust end surface and increasing the contact area during installation of the exhaust pipe. The contact surface is smoother, and the support area of ​​the exhaust pipe gasket is increased, thereby effectively improving the assembly sealing of the exhaust surface and reducing the risk of air leakage and oil leakage in the exhaust pipe.

[0016] The utility model adopts a cylinder head body to open a sand cleaning hole connected to the cooling water channel on the side wall on the right side of the exhaust end face of the cylinder head body, which can completely clean out the sand remaining in the narrow part of the cooling water channel built into the cylinder head after the casting is completed, further avoiding the damage to various water channel sealing components caused by the sand remaining in the cooling water channel when the coolant circulates in the diesel engine cooling system. The reliability of the diesel engine is improved and the frequency of diesel engine coolant leakage failures is reduced.

[0017] The utility model adopts a bifurcated "Y"-shaped exhaust duct, in whose inner cavity, a diversion ridge extending to the main air duct is integrally formed at the lower part of the intersection of the two branch air ducts, and the diversion ridge adopts a ridge-shaped structure. It is arranged symmetrically with the intersection line of the two branch air ducts as the axis, and the width of the diversion ridge increases from top to bottom along the length direction of the intersection line, so that the flow of fluid particles in the cylinder head exhaust duct shows obvious upper and lower stratification. The upper fluid smoothly intersects and flows out of the main air duct. No vortex is generated at the intersection of the two branch air ducts, and the flow is smooth. The lower part of the intersection of the two branch air ducts is integrally formed with a diversion ridge extending to the main air duct. When the two branch air ducts begin to merge, the lower fluid shows obvious vortex and shows signs of vortex mixing. The lower exhaust shows obvious backflow phenomenon, which increases the residence time of the exhaust in the main air duct of the cylinder head and strengthens the secondary mixing of the exhaust. It can make the unburned fuel and oxygen mix for the second time and burn in the cylinder head air duct, reduce the afterburning of the mixed exhaust gas in the exhaust pipe, reduce the exhaust pipe temperature, reduce the emission of CH compounds and carbon soot particles, and improve the emission performance of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural diagram of a water-cooled diesel engine cylinder head in the background technology of the present utility model;

[0019] Figure 2 This is a schematic diagram of the top structure of the high-pressure common rail diesel engine cylinder head of the utility model;

[0020] Figure 3 This is a schematic diagram of the bottom structure of the high-pressure common rail diesel engine cylinder head of the utility model;

[0021] Figure 4 This is an enlarged schematic diagram of the exhaust end of the cylinder head of a high-pressure common rail diesel engine of the present invention;

[0022] Figure 5 This is a schematic structural diagram of the exhaust passage in the cylinder head of a high-pressure common rail diesel engine of the present invention;

[0023] Among them, 1. Cylinder head body, 2. Single exhaust outlet, 3. Exhaust end face, 4. Cooling water channel process hole, 5. Process boss, 6. Sand cleaning hole, 7. Diverter ridge, 8. Branch air channel, 9. Main air channel, 10. Exhaust inlet. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below with reference to the embodiments:

[0025] like Figure 2-Figure 5 As shown, the utility model provides a new type of high-pressure common rail diesel engine cylinder head, which mainly includes a cylinder head body 1 and a bifurcated "Y"-shaped exhaust duct, a dual-air duct structure intake duct, an injector hole and a cooling water duct arranged inside the cylinder head body 1. Among them, the single exhaust outlet 2 of the exhaust duct is arranged on the exhaust end face 3 at the lower end of the cylinder head body 1, and its two exhaust inlets 10 are arranged side by side on the fire surface of the bottom surface of the cylinder head body 1; the intake duct consists of a spiral air duct and a straight air duct, and the two intake inlets of the intake duct are arranged side by side on the cylinder head body 1. On the air intake end face at the upper end of the cover body 1, the two air intake outlets of the intake duct and the two exhaust inlets 10 of the exhaust duct are arranged parallel to each other on the fire surface of the bottom surface of the cylinder head, and the corresponding valve seat rings are respectively set with interference fit; the injector hole passes through the center position of the four air duct openings on the bottom surface of the cylinder head to the top surface of the cylinder head; the cooling water channel is wrapped around the intake duct and the exhaust duct, and the three cooling water channel process holes 4 of the cooling water channel are respectively opened at the lower left corner of the top surface of the cylinder head body 1 and its left and right end surfaces. The cylinder head needs to be sealed when in use.

[0026] Furthermore, a concave cavity is formed at the junction of the top surface of the cylinder head body 1 and its exhaust end surface 3, and a process boss 5 is integrally formed in the concave cavity and is flush with the exhaust end surface 3. Correspondingly, the cooling water channel process hole 4 located at the lower left corner of the top surface of the cylinder head body 1 is disposed in the concave cavity to the left of the process boss 5. Compared with a water-cooled diesel engine cylinder head disclosed in Chinese patent document CN221220644U, the exhaust end surface 3 of the present utility model is additionally provided with a process boss 5 that is flush with it, thereby effectively increasing the area of ​​the exhaust end surface 3, that is, increasing the contact area during exhaust pipe installation. The contact surface is also smoother, increasing the support area of ​​the exhaust pipe gasket, thereby effectively improving the assembly sealing of the exhaust surface and reducing the risk of exhaust pipe leakage.

[0027] Furthermore, a sand cleaning hole 6 connected to the cooling water channel is opened on the side wall of the cylinder head body on the right side of its exhaust end face. The cylinder head needs to be sealed when in use. Compared with a water-cooled diesel engine cylinder head disclosed in Chinese patent document CN221220644U, the utility model can completely clean out the sand remaining in the narrow part of the built-in cooling water channel of the cylinder head after casting, further avoiding the damage to various water channel sealing components caused by the sand remaining in the cooling water channel when the coolant circulates in the diesel engine cooling system, thereby improving the reliability of the diesel engine as a whole and reducing the frequency of diesel engine coolant leakage failures.

[0028] Furthermore, the exhaust duct is an integrally formed structure, which includes two branch air ducts 8 and a main air duct 9. The two branch air ducts 8 are respectively connected to the two exhaust inlets 10. One end of the main air duct 9 is connected to the single exhaust outlet 2, and the other end is connected to the two branch air ducts 8. The ends of the two branch air ducts 8 connected to one end of the main air duct 9 intersect, that is, the side walls of the ends of the two branch air ducts 8 are connected to each other, so that the exhaust duct as a whole has a forked "Y"-shaped structure. In the inner cavity of the exhaust duct, the lower part of the intersection of the two branch air ducts 8 is integrally formed with a diverter ridge 7 extending to the main air duct 9, that is, the diverter ridge 7 is obliquely set at the junction of the two branch air ducts 8 and the main air duct 9.

[0029] Specifically, the diverter ridge 7 is a ridge-like structure for guiding the airflow, which is arranged symmetrically with the intersection line of the two branch airways 8 as the axis, and the width of the diverter ridge 7 increases from top to bottom along the length direction of the intersection line, that is, the upper end of the diverter ridge 7, which is close to the branch airway 8, is narrower, and the lower end, which is close to the main airway 9, is wider. Preferably, the diverter ridge 7 is nose-shaped, and the highest point of its uplift is set close to the main airway 9. The uplift height of the diverter ridge 7 decreases from its highest point to its upper and lower ends respectively, that is, with the highest point of the uplift of the diverter ridge 7 as the boundary, the uplift slope on the side close to the main airway 9 is greater than the uplift slope on the side close to the branch airway 8. Therefore, compared with a water-cooled diesel engine cylinder head disclosed in Chinese patent document CN221220644U, the setting of the diverter ridge 7 causes the flow of fluid particles in the exhaust duct of the cylinder head of the utility model to show obvious upper and lower stratification phenomenon. The upper fluid smoothly converges and flows out of the main air duct 9. No vortex is generated at the intersection of the two branch air ducts 8, and the flow is smooth. Since the lower part of the intersection of the two branch air ducts 8 is integrally formed with a diverter ridge 7 extending to the main air duct 9, the lower fluid shows obvious vortex at the beginning of the convergence of the two branch air ducts 8, and shows signs of vortex mixing. The lower exhaust shows obvious backflow phenomenon, which increases the residence time of the exhaust in the main air duct of the cylinder head and strengthens the secondary mixing of the exhaust. It can make the unburned fuel and oxygen mix for the second time and burn in the cylinder head air duct, reduce the afterburning of the mixed exhaust gas in the exhaust pipe, reduce the exhaust pipe temperature, reduce the emission of CH compounds and carbon soot particles, and improve the emission performance of the whole machine.

[0030] The other component structures, positional relationships, and connection methods of the high-pressure common rail diesel engine cylinder head of this utility model are identical to those of a water-cooled diesel engine cylinder head disclosed in Chinese patent document CN221220644U. Specifically, the exhaust duct has blind holes provided on the sidewalls near the two exhaust inlets near the exhaust valves, or within one of the exhaust inlets. The open ends of the blind holes communicate with the exhaust duct, and the closed ends extend to the cooling water channel. The blind holes are used to mount the brake valve. During installation, the blind holes are finely machined to open the closed ends, and the brake valve is installed within the machined blind holes.

[0031] A connecting pipe hole is provided on the upper end surface of the cylinder head and extends through to the injector hole to form an oil delivery channel. A connecting pipe is installed in the connecting pipe hole. A fuel return channel is provided on the top surface of the cylinder head near the connecting pipe hole. The fuel return channel connects to the connecting pipe hole through an internal oil channel in the cylinder head, which intersects with the oil delivery channel.

[0032] The cooling water channel inlet is arranged at the single exhaust outlet of the exhaust channel on the bottom surface of the cylinder head, and the cooling water channel outlet is arranged between the two air inlets of the air inlet channel on the bottom surface of the cylinder head.

[0033] The cylinder head has an oil return hole on its top surface, located near the exhaust inlet on the left side of the exhaust duct. It extends obliquely from the top surface to the bottom surface. A pushrod hole is also located on the top surface of the cylinder head. This hole is located between the spiral and straight ducts and extends from the top surface to the bottom surface. The shape of the hole is based on the trajectory of the pushrod during one swing.

[0034] There are multiple component fixing holes around the surface of the cylinder head, including exhaust manifold fixing holes around the exhaust duct outlet, cylinder head fixing holes symmetrically arranged on both sides of the top surface of the cylinder head and penetrating from the top surface to the bottom surface, rocker arm fixing holes arranged between the push rod special-shaped holes on the top surface of the cylinder head and the intake valve guide, valve chamber body fixing holes arranged around the top surface of the cylinder head, and intake pipe fixing holes arranged on the upper end surface of the cylinder head.

[0035] The exhaust duct's two exhaust inlets are interference-fitted with corresponding exhaust valve seats, while the intake duct's two intake outlets are interference-fitted with corresponding intake valve seats. Corresponding intake and exhaust valve guides are located above the intake and exhaust ducts. The intake duct is located in the upper half of the cylinder head, while the exhaust duct is located in the lower half.

[0036] It is understood that the present invention is described by way of certain embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. Furthermore, under the guidance of the present invention, these features and embodiments may be modified to suit specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. A novel high-pressure common rail diesel engine cylinder head, comprising a cylinder head body (1) and a bifurcated "Y"-shaped exhaust duct, a dual-air duct intake duct, an injector hole and a cooling water duct arranged inside the cylinder head body (1), wherein a single exhaust outlet (2) of the exhaust duct is arranged on an exhaust end face (3) at the lower end of the cylinder head body (1), and two exhaust inlets (10) thereof are arranged on the bottom face of the cylinder head body (1), a cooling water duct is arranged around the intake duct and the exhaust duct, and three cooling water duct process holes (4) of the cooling water duct are respectively opened at the lower left corner of the top face of the cylinder head body (1) and at both left and right end faces thereof, characterized in that: A concave cavity is provided at the junction of the top surface of the cylinder head body (1) and the exhaust end surface (3), and a process boss (5) flush with the exhaust end surface (3) is integrally formed in the concave cavity. The cooling water channel process hole (4) at the lower left corner of the top surface of the cylinder head body (1) is provided in the concave cavity on the left side of the process boss (5).

2. A novel high-pressure common rail diesel engine cylinder head according to claim 1, characterized in that: The cylinder head body (1) is provided with a sand cleaning hole (6) on the side wall on the right side of the exhaust end surface (3) thereof, the sand cleaning hole (6) being in communication with the cooling water channel.

3. The novel high-pressure common rail diesel engine cylinder head according to claim 2, characterized in that: The exhaust duct is an integrally formed structure, comprising branch air ducts (8) respectively connected to the two exhaust inlets (10) and a main air duct (9) connected at one end to the single exhaust outlet (2) and at the other end to the two branch air ducts (8), wherein the ends of the two branch air ducts (8) connected to one end of the main air duct (9) intersect.

4. A novel high-pressure common rail diesel engine cylinder head according to claim 3, characterized in that: In the inner cavity of the exhaust duct, a diversion ridge (7) extending to the main air duct (9) is integrally formed at the lower portion of the intersection of the two branch air ducts (8).

5. The novel high-pressure common rail diesel engine cylinder head according to claim 4 is characterized in that: The diversion ridge (7) is a ridge-shaped structure for guiding airflow, which is arranged symmetrically with the intersection line of the two branch airways (8) as the axis, and the width of the diversion ridge (7) increases from top to bottom along the length direction of the intersection line.

6. The novel high-pressure common rail diesel engine cylinder head according to claim 5, characterized in that: The highest point of the diversion ridge (7) is located close to the main airway (9), and the height of the diversion ridge (7) decreases from its highest point to its upper and lower ends.

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