Piston cooling device

Abstract

The utility model relates to a piston cooling device which comprises a valve body and an oil spraying pipe communicated with the valve body, the valve body is used for receiving oil liquid, a nozzle opening of the oil spraying pipe is provided with a diffusion type flow guiding part, the diffusion type flow guiding part is used for diffusing the oil liquid into oil mist with a preset divergence angle, and the oil liquid is diffused through the diffusion type flow guiding part to form a fan-shaped oil mist covering area. The problem that the piston cooling coverage range is insufficient is effectively solved; the method has the advantages that the piston cooling efficiency is improved, the working temperature of the piston is more uniform, the thermal stress is reduced, the cold start efficiency and time are improved, the cold start resistance is reduced, the temperature of a combustion chamber is rapidly increased, the combustion efficiency is improved, the fuel economy is improved, the engine power is improved, and the emission performance is good.

Description

Technical Field

[0001] This utility model relates to the field of cooling nozzles, and in particular to a piston cooling device. Background Technology

[0002] In the field of turbocharged engines, carbon buildup, seizure, and erosion caused by high piston temperatures have become significant technical bottlenecks restricting engine reliability. Currently, the mainstream solution in the industry is to install a piston cooling device in the cylinder block, using directional oil injection to achieve heat exchange and cooling. However, existing technologies still have significant shortcomings in terms of cooling coverage, structural layout, and cost control.

[0003] Currently, piston cooling devices mainly include single-nozzle, double-nozzle, and triple-nozzle structures. For example, the single-nozzle structure (as shown in the technical solution CN201520788967) uses a single curved nozzle, whose spray trajectory can only cover the central area of ​​the piston bottom. This point-cooling method cannot effectively solve the problem of high temperature accumulation in the main thrust surface and secondary thrust surface areas. Especially under high engine load conditions, there is still a risk of thermal failure on both sides of the piston skirt.

[0004] The patent employs a dual-nozzle structure (as shown in CN201310252341), with one nozzle cooling the intake side (cooling the main thrust side) and the other cooling the exhaust side (cooling the secondary thrust side). However, this patent only cools the main and secondary thrust sides. The bottom center of a single piston often has a high temperature, but this structure does not provide cooling. Furthermore, using two nozzles in one engine doubles the nozzle cost. This structure also requires a main oil passage to be arranged on both the intake and exhaust sides of the cylinder block, increasing the difficulty of cylinder block arrangement and raising manufacturing costs.

[0005] While the three-nozzle structure (such as the technical solution shown in CN111911276A) addresses the cooling blind zone problem through multi-dimensional spraying, it is limited by the scattering characteristics of the high-pressure oil jet. After impacting a point on the piston, the oil jet is reflected back, resulting in a discrete point-like cooling effect that cannot form an effective area coverage. Furthermore, the three-nozzle layout significantly increases the probability of internal space conflicts within the engine, especially in the piston-connecting rod motion envelope, which can easily lead to mechanical interference, limiting its practical engineering application value. In addition, the doubling of the number of nozzles significantly increases production costs, and the reliability of the multi-oil circuit system faces severe challenges.

[0006] Furthermore, all three structures exhibit the characteristics of a surge in main oil passage pressure, high cold start resistance, and slow combustion chamber temperature rise during the cold start phase.

[0007] Therefore, there is an urgent need for a piston cooling device to improve piston cooling efficiency, make piston working temperature more uniform, reduce thermal stress, improve cold start efficiency and time, reduce cold start resistance, enable rapid heating of the combustion chamber, improve combustion efficiency, enhance fuel economy, increase engine power, and achieve good emission performance. Utility Model Content

[0008] In view of this, the present invention provides a piston cooling device that improves piston cooling efficiency, makes piston working temperature more uniform, reduces thermal stress, improves cold start efficiency and time, reduces cold start resistance, enables rapid heating of the combustion chamber, improves combustion efficiency, enhances fuel economy, increases engine power, and provides good emission performance.

[0009] The piston cooling device provided by this utility model adopts the following technical solution:

[0010] A piston cooling device includes a valve body and an oil injection pipe communicating with the valve body. The valve body is used to receive oil, and the nozzle of the oil injection pipe has a diffuser section for diffusing the oil into an oil mist with a predetermined divergence angle.

[0011] Optionally, the diffusion guide is used to diffuse the oil to form a fan-shaped oil mist coverage area with a divergence angle θ ranging from 0° to 120°.

[0012] Optionally, the diffuser includes a frustum-shaped flared section that extends continuously from the inner wall of the nozzle opening to the outlet end.

[0013] Optionally, the included angle α between the conical surface of the frustum-shaped flared section and the axial direction of the fuel injection pipe is in the range of 30°≤α≤60°.

[0014] Optionally, the fuel injection pipe includes a connecting pipe and a fuel outlet pipe. The connecting pipe communicates with the valve body, and the fuel outlet pipe communicates with the connecting pipe. The fuel outlet pipe is rotatably and lockably fitted onto the connecting pipe.

[0015] Optionally, the connecting pipe is provided with a driving mechanism, which includes an oil chamber and a driving component. The oil chamber is in communication with the connecting pipe and the oil outlet pipe respectively, and the driving component is used to control the rotation angle of the oil outlet pipe.

[0016] Optionally, the drive unit can control the rotation of the oil outlet pipe so that the oil mist sprayed from the nozzle avoids the piston.

[0017] Optionally, the valve body is provided with a bracket for fixing the valve body to the cylinder.

[0018] In summary, this utility model includes at least one of the following beneficial technical effects: by using a diffusion guide to diffuse the oil and form a fan-shaped oil mist coverage area, the problem of insufficient piston cooling coverage is effectively solved. It has the advantages of improving piston cooling efficiency, making the piston working temperature more uniform, reducing thermal stress, improving cold start efficiency and time, reducing cold start resistance, enabling the combustion chamber to heat up quickly, improving combustion efficiency, improving fuel economy, improving engine power, and providing good emission performance. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present utility model;

[0020] Figure 2 This is a schematic diagram of the flared section structure of the frustum-shaped section according to an embodiment of the present invention.

[0021] Explanation of reference numerals in the attached drawings: 1. Valve body; 2. Bracket; 3. Frustum-shaped flared section; 4. Connecting pipe; 5. Oil outlet pipe; 6. Drive mechanism. Detailed Implementation

[0022] The following is in conjunction with the appendix Figure 1-2 The present invention will be described in further detail below.

[0023] This utility model discloses a piston cooling device.

[0024] Reference Figure 1 and Figure 2 A piston cooling device includes a valve body 1 and an injection pipe that flows through the valve body 1. The valve body 1 is used to receive oil. The nozzle of the injection pipe has a diffuser section, which is used to diffuse the oil into an oil mist with a predetermined divergence angle, forming a fan-shaped oil mist coverage area. This effectively solves the problem of insufficient piston cooling coverage and has the advantages of improving piston cooling efficiency, making the piston working temperature more uniform, reducing thermal stress, improving cold start efficiency and time, reducing cold start resistance, enabling the combustion chamber to heat up quickly, improving combustion efficiency, improving fuel economy, improving engine power, and providing good emission performance.

[0025] This invention, through the design of a diffuser-type flow guide, can uniformly diffuse the oil into an oil mist with a predetermined divergence angle, thereby expanding the cooling coverage area and improving the piston cooling efficiency. Compared with existing technologies, this solution avoids the problems of limited cooling range of single-nozzle structures, high cost and complex arrangement of dual-nozzle structures, and spatial conflicts and poor reliability of three-nozzle structures. By optimizing the diffusion characteristics of the oil mist, this solution can effectively reduce piston thermal stress, reduce carbon deposits and jamming, while improving cold start efficiency, shortening combustion chamber warm-up time, and enhancing overall engine performance.

[0026] A diffuser is used to diffuse oil into a fan-shaped oil mist coverage area with a divergence angle θ ranging from 0° to 120°. The diffuser can uniformly diffuse the oil, forming a fan-shaped oil mist coverage area with a specific divergence angle. Specifically, the diffuser achieves this by changing the geometry of the nozzle orifice, for example, by using a frustum-shaped, conical, arc-shaped, or stepped structure to optimize the oil mist diffusion effect.

[0027] In this embodiment, the diffusion guide includes a frustum-shaped flared section 3 that extends continuously from the inner wall of the nozzle orifice to the outlet end. The frustum-shaped flared section 3 allows the oil to gradually diffuse as it passes through the nozzle orifice, forming a more uniform oil mist distribution. Specifically, the frustum-shaped flared section 3 refers to a frustum structure that extends continuously from the inner wall of the nozzle orifice to the outlet end. The angle α between its conical surface and the axial direction of the injection pipe determines the angle and range of oil diffusion.

[0028] In this embodiment, the included angle α between the conical surface of the frustum-shaped flared section 3 and the axial direction of the fuel injection pipe is in the range of 30°≤α≤60°, which allows the oil to be effectively diffused and form a fan-shaped oil mist when passing through the diffuser section, covering a wider range and thus improving the cooling effect.

[0029] Specifically, the design of the diffuser section can achieve different divergence angles by adjusting the cone angle of the frustum-shaped flared section 3. For example, when the cone angle is 30°, the divergence angle of the oil is smaller, and the oil mist coverage area is more concentrated; while when the cone angle is 60°, the divergence angle of the oil is larger, and the oil mist coverage area is more extensive.

[0030] In other embodiments, the diffuser section may also adopt other shapes of flared sections, such as parabolic or hyperbolic shapes, to achieve different oil mist diffusion effects.

[0031] In this embodiment, the oil is engine oil, and the valve body 1 adopts the existing technology valve body 1, so that the engine oil in the main oil passage of the cylinder enters the valve body 1 and then enters the fuel injection pipe.

[0032] The fuel injection pipe includes a connecting pipe 4 and a fuel outlet pipe 5. The connecting pipe 4 communicates with the valve body 1, and the fuel outlet pipe 5 communicates with the connecting pipe 4. The fuel outlet pipe 5 has an end cap at the outlet end, and the nozzle opening is opened on the end cap. The fuel outlet pipe 5 is rotatably and lockably fitted to the connecting pipe 4. The flow between the connecting pipe 4 and the valve body 1 allows the fuel to smoothly enter the fuel injection pipe, and the flow between the fuel outlet pipe 5 and the connecting pipe 4 allows the fuel to flow from the connecting pipe 4 to the fuel outlet pipe 5.

[0033] The oil outlet pipe 5 is rotatably fitted to the connecting pipe 4 in a lockable manner, allowing the oil outlet pipe 5 to rotate within a specified range. This allows the nozzle direction of the oil outlet pipe 5 to be adjusted as needed, thereby achieving precise cooling of different areas of the piston.

[0034] In this embodiment, a driving mechanism 6 is provided on the connecting pipe 4. The driving mechanism 6 includes an oil chamber, a first connecting pipe, a second connecting pipe, and a driving component. The oil chamber flows through the first connecting pipe and the second connecting pipe, and the first connecting pipe and the second connecting pipe flow through the connecting pipe 4 and the oil outlet pipe 5, respectively. The driving component is used to control the rotation angle of the oil outlet pipe 5. The driving mechanism 6 flows through the oil chamber to the connecting pipe 4 and the oil outlet pipe 5, so that oil can enter the driving mechanism 6, thereby driving the rotation of the oil outlet pipe 5.

[0035] Connecting pipe one and connecting pipe two can be an integrated flexible hose with an oil chamber, and the driving component uses a motor with a lead wire to drive the corresponding connecting pipe to rotate. Alternatively, they can be two separate pipes, which are rotated by a motor. This technology is existing technology and will not be described in detail here.

[0036] The driving component can be an electric cylinder, a motor, or other device capable of providing rotational power. By controlling the movement of the driving component, the rotation angle of the oil outlet pipe 5 can be precisely adjusted. In this embodiment, a motor is used as the driving component. To further improve the rotation accuracy of the oil outlet pipe 5 and ensure that the oil mist coverage area covers the designated area, a motor with angle detection is preferred, such as a Hall sensor motor, a photoelectric encoder motor, or a magnetic encoder motor.

[0037] The motor can drive the oil outlet pipe 5 to rotate, and by driving the oil outlet pipe 5 to swing back and forth continuously, the oil jet can cover the piston over a large area. The swing speed can be controlled according to the engine load and water temperature to accelerate or reduce the piston cooling efficiency, so as to adapt to various engine operating conditions.

[0038] In this embodiment, the drive unit can control the oil outlet pipe 5 to rotate so that the oil mist sprayed from the nozzle avoids the piston. When the engine is started cold, the piston does not need to be cooled. At this time, the drive mechanism 6 adjusts the angle of the oil outlet pipe 5 so that the spray direction is away from the piston, and the oil mist cannot be sprayed onto the piston. When the oil is not sprayed onto the piston, the piston temperature rises rapidly, which makes the combustion chamber temperature rise, which is beneficial to fuel atomization and combustion, and accelerates the preheating of the combustion chamber.

[0039] In this embodiment, a bracket 2 is provided on the valve body 1, which is used to fix the valve body 1 to the cylinder block. In this embodiment, the bracket 2 secures the valve body 1 to the cylinder block with bolts to ensure the stability of the nozzle during engine operation.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A piston cooling device, characterized in that: It includes a valve body and a fuel injection pipe that flows through the valve body. The valve body is used to receive fuel, and the nozzle of the fuel injection pipe has a diffuser section for diffusing the fuel into a mist with a predetermined divergence angle. The diffusion guide section includes a frustum-shaped flared section that extends continuously from the inner wall of the nozzle opening to the outlet end. The included angle α between the conical surface of the frustum-shaped flared section and the axial direction of the fuel injection pipe is in the range of 30°≤α≤60°.

2. The piston cooling device according to claim 1, characterized in that: The diffusion-type guide section is used to diffuse the oil to form a fan-shaped oil mist coverage area with a divergence angle θ ranging from 0° to 120°.

3. The piston cooling device according to claim 1, characterized in that: The fuel injection pipe includes a connecting pipe and a fuel outlet pipe. The connecting pipe communicates with the valve body, and the fuel outlet pipe communicates with the connecting pipe. The fuel outlet pipe is rotatably and lockably fitted onto the connecting pipe.

4. The piston cooling device according to claim 3, characterized in that: The connecting pipe is provided with a driving mechanism, which includes an oil chamber and a driving component. The oil chamber is in flow with the connecting pipe and the oil outlet pipe respectively, and the driving component is used to control the rotation angle of the oil outlet pipe.

5. The piston cooling device according to claim 4, characterized in that: The drive unit can control the rotation of the oil outlet pipe so that the oil mist sprayed from the nozzle avoids the piston.

6. The piston cooling device according to claim 1, characterized in that: The valve body is provided with a bracket, which is used to fix the valve body to the cylinder.

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