Gravity regulated vented expansion tank for engine cooling system

Abstract

The utility model discloses a gravity pressure stabilization exhaust expansion water tank for engine cooling system, include: water tank body, the water tank body side wall is equipped with cooling liquid import and is equipped with cooling liquid export in the bottom, exhaust pressure stabilization unit is set up in the water tank body top portion, including with exhaust cavity of water tank body intercommunication, with piston of exhaust cavity inner wall sliding seal cooperation, lower portion with piston is connected and upper portion extends to the piston rod of exhaust cavity above and sets up in the counterweight assembly of piston rod upper portion, exhaust cavity has exhaust port. The utility model provides expansion water tank, exhaust pressure is adjustable, adopts counterweight assembly to provide exhaust pressure constant, improves exhaust sensitivity, and then improves cooling efficiency.

Description

Technical Field

[0001] This utility model relates to the field of engine technology, and in particular to a gravity-pressure-stabilized exhaust expansion tank for an engine cooling system. Background Technology

[0002] During engine bench testing, phenomena such as localized boiling and insufficient vapor-liquid separation often occur within the cooling system, particularly in the high-temperature areas of the cylinder head and the hot end of the EGR cooler. Air bubbles carried in the high-temperature coolant accumulate in large quantities inside the water jacket, causing a sharp rise in localized temperature, leading to uneven cooling, increased localized thermal stress, and abnormal experimental data. To promptly expel these vaporized gases, engines typically have a degassing connector installed in the hot-end water passages, which is then connected to the expansion tank.

[0003] Most existing expansion tanks use spring-loaded pressure relief valves to achieve pressure stabilization and venting, with the venting pressure determined by the spring stiffness, such as the automatic pressure-stabilizing expansion tank cover disclosed in Chinese patent CN205117483U. However, this structure has the following shortcomings:

[0004] (1) The spring stiffness decays with temperature and usage time due to fatigue, resulting in exhaust pressure drift and poor long-term stability;

[0005] (2) The opening characteristics of the spring valve are relatively steep, and pressure fluctuations are likely to occur during the exhaust process, which is not conducive to the precise control of system pressure in bench tests.

[0006] (3) When local boiling is intense, the spring valve is limited by its structural characteristics and its exhaust response is not sensitive enough, which can easily lead to gas accumulating inside the engine for a long time, affecting the stability of the experiment or even damaging the engine. Utility Model Content

[0007] In order to solve the problems of the prior art, the purpose of this utility model is to provide a gravity-stabilized exhaust expansion tank for engine cooling systems, which has high stability and adjustable exhaust pressure.

[0008] Based on the above problems, the technical solution provided by this utility model is as follows:

[0009] Gravity-stabilized exhaust expansion tank for engine cooling systems includes:

[0010] The water tank body has a coolant inlet on its side wall and a coolant outlet at its bottom.

[0011] An exhaust pressure stabilizing unit is disposed on the upper part of the water tank body, including an exhaust chamber communicating with the interior of the water tank body, a piston that slides and seals with the inner wall of the exhaust chamber, a piston rod whose lower part is connected to the piston and whose upper part extends to the top of the exhaust chamber, and a counterweight assembly disposed on the upper part of the piston rod. The exhaust chamber has an exhaust port.

[0012] In one embodiment, a guide component is fixed to the upper end of the exhaust chamber, the guide component having a guide groove that runs vertically through the chamber, and the piston rod passes through the guide groove.

[0013] In one embodiment, the exhaust chamber is a cylindrical structure and is integrally formed on the upper end of the water tank body.

[0014] In one embodiment, a limit nut is fixed to the upper part of the piston rod, and the counterweight assembly is sleeved on the piston rod with its lower end abutting against the limit nut.

[0015] In one embodiment, the counterweight assembly includes several counterweight blocks stacked vertically.

[0016] In one embodiment, the exhaust port is provided with an upwardly bent exhaust pipe.

[0017] In one embodiment, a liquid level monitoring unit is also included, the liquid level monitoring unit comprising a liquid level gauge arranged along the height direction of the water tank body, a first connecting pipe connecting the lower part of the liquid level gauge to the lower part of the water tank body, and a second connecting pipe connecting the upper part of the liquid level gauge to the upper part of the water tank body.

[0018] In one embodiment, the level gauge is a transparent tube with graduations on its outer wall arranged along the height of the water tank body.

[0019] In one embodiment, a pressure monitoring unit is further included, which is a pressure gauge installed on the upper part of the water tank body, and the pressure measuring end of the pressure gauge is connected to the interior of the water tank body.

[0020] In one embodiment, a replenishment unit is also included, the replenishment unit comprising a water inlet disposed at the upper end of the water tank body and a sealing cap that cooperates with the water inlet.

[0021] Compared with the prior art, the advantages of this utility model are:

[0022] (1) The pressure is stabilized by the gravity of the counterweight assembly, which will not drift over time, overcomes the problem of exhaust pressure change caused by spring fatigue, has high long-term stability, effectively avoids abnormal engine temperature rise caused by local steam resistance and uneven cooling, and improves experimental stability and engine safety.

[0023] (2) High exhaust sensitivity; the pressure increase generated by local boiling can immediately drive the piston to open the exhaust passage, effectively reducing gas accumulation in the cylinder head and high-temperature area, and improving vapor-liquid separation efficiency and cooling efficiency.

[0024] (3) The exhaust pressure is adjustable. The exhaust opening pressure can be changed by adjusting the counterweight mass, which is suitable for bench testing of multiple engine models.

[0025] (4) Equipped with pressure monitoring unit and liquid level monitoring unit, it has pressure visualization and liquid level monitoring capabilities, enabling test personnel to monitor the operating status of the cooling system in real time, thereby improving test safety and data reliability. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the following description of the embodiments will be briefly introduced. The drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of an embodiment of the gravity-stabilized exhaust expansion tank for an engine cooling system according to this utility model;

[0028] in:

[0029] 1. Water tank body; 1-1. Coolant inlet; 1-2. Coolant outlet;

[0030] 2. Exhaust chamber;

[0031] 3. Piston;

[0032] 4. Piston rod;

[0033] 5. Counterweight;

[0034] 6. Guide components;

[0035] 7. Limit nut;

[0036] 8. Exhaust pipe;

[0037] 9. Level gauge;

[0038] 10. First connecting tube;

[0039] 11. Second connecting pipe;

[0040] 12. Pressure gauge;

[0041] 13. Water injection port;

[0042] 14. Sealing cap. Detailed Implementation

[0043] The above solution will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrating the present invention and are not intended to limit the scope of the present invention. The implementation conditions used in the embodiments can be further adjusted according to the conditions of specific manufacturers, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0044] See Figure 1 The above is a schematic diagram of an embodiment of the present invention, which provides a gravity-stabilized exhaust expansion tank for an engine cooling system, including a tank body 1, and an exhaust pressure stabilizing unit, a liquid level monitoring unit, a pressure monitoring unit and a liquid replenishment unit disposed on the tank body 1.

[0045] The water tank body 1 is a three-dimensional container structure for holding coolant, made of stainless steel. A coolant inlet 1-1 is provided on the side wall of the water tank body 1 to receive high-temperature liquid-gas mixture fluid from the hot end of the engine cylinder head or the degassing connector of the hot end of the EGR cooler. A coolant outlet 1-2 is provided at the bottom of the water tank body 1, communicating with the inlet of the test bench's circulating water system to achieve coolant return.

[0046] The exhaust pressure stabilizing unit is located on the upper part of the water tank body 1. It includes an exhaust chamber 2 communicating with the interior of the water tank body 1, a piston 3 that slides and seals against the inner wall of the exhaust chamber 2, a piston rod 4 connected to the piston 3 at the bottom and extending to the exhaust chamber 2 at the top, and a counterweight assembly located on the upper part of the piston rod 4. An exhaust port is provided on the exhaust chamber 2. When the air pressure inside the water tank body 1 changes, the piston 3 moves up and down in the exhaust chamber 2. When the piston 3 moves above the exhaust port, the gas inside the water tank body 2 can be discharged through the exhaust port. When the air pressure inside the water tank body 2 stabilizes, the piston 3 descends below the exhaust port under the action of gravity, thereby stabilizing the air pressure inside the water tank body 1.

[0047] In this example, the exhaust chamber 2 is a cylindrical structure and is integrally formed on the upper end of the water tank body 1. The piston 3 is made of stainless steel or aluminum alloy and is sealed with a sealing ring between it and the inner wall of the exhaust chamber 2.

[0048] To further optimize the implementation effect of this utility model and avoid the piston rod 4 from shifting and getting stuck during the up and down movement, a guide component 6 is fixed at the upper end of the exhaust chamber 2. The guide component 6 has a guide groove that runs through the upper and lower parts. The piston rod 4 passes through the guide groove. When the piston 3 moves up and down, the piston rod 4 can move up and down along the guide component 6 to avoid the problem of shifting.

[0049] To facilitate the installation of the counterweight assembly, a limit nut 7 is fixed on the piston rod 4. The counterweight assembly is sleeved on the piston rod 4 and its lower end abuts against the limit nut 7. Specifically, the upper part of the piston rod 4 can be a threaded rod body, and the limit nut 7 is threadedly connected to the threaded rod body.

[0050] The counterweight assembly provides a constant downward force to create the exhaust initiation pressure. It consists of several counterweight blocks 5 stacked vertically, each with a through-hole for mounting on the piston rod 4. When the pressure in the gas phase space inside the water tank 1 rises to a value greater than the ratio of the counterweight's weight to the effective pressure-bearing area of ​​the piston 3, the piston 3 moves upward to open the exhaust passage; when the pressure drops, the piston 3 moves downward to close the exhaust passage, thus achieving automatic pressure stabilization and exhaust.

[0051] The exhaust opening pressure P_start satisfies the balance relationship:

[0052]

[0053] in,

[0054] m - The total mass of the counterweight and piston rod, etc.

[0055] A - Effective pressure-bearing area of ​​the piston;

[0056] g - gravitational acceleration.

[0057] By adjusting the mass m of the counterweight 5 or the diameter of the piston 3 to change A, the exhaust pressure can be flexibly adjusted to adapt to different engine types and test conditions.

[0058] To improve exhaust safety, an upward-bent exhaust pipe 8 is provided at the exhaust port.

[0059] The liquid level monitoring unit is used to visually display the liquid level inside the water tank body 1. It includes a liquid level gauge 9 arranged along the height direction of the water tank body 1, a first connecting pipe 10 connecting the lower part of the liquid level gauge 9 to the lower part of the water tank body 1, and a second connecting pipe 11 connecting the upper part of the liquid level gauge 9 to the upper part of the water tank body 1. The liquid level gauge 9 is a transparent tube and has scale lines arranged along the height direction of the water tank body 1 on its outer wall.

[0060] The pressure monitoring unit is used to monitor the pressure changes of the engine cooling system. Specifically, the pressure monitoring unit is a pressure gauge 12 installed on the upper end of the water tank body 1, and the measuring end of the pressure gauge 12 is connected to the inside of the water tank body 1.

[0061] The coolant replenishment unit is used for replenishing and maintaining the coolant in the water tank body 1. It includes a water inlet 13 provided on the water tank body 1 and a sealing cap 14 that cooperates with the water inlet 13. The sealing cap 14 is detachably provided on the water inlet 13.

[0062] The working principle of this utility model is as follows:

[0063] During engine operation, air bubbles enter the water tank body 1 along with the liquid and complete vapor-liquid separation inside; when the internal pressure of the water tank body 1 increases, the piston 3 moves upward to above the exhaust port under the action of air pressure to open the exhaust passage and release gas; after the pressure decreases, the piston 3 descends to below the exhaust port to automatically close the exhaust passage and achieve system pressure stabilization.

[0064] In summary, this expansion tank can adjust the exhaust pressure as needed, and the exhaust pressure is constant, solving the problems of insensitive exhaust response and difficulty in local gas accumulation, and improving the gas-liquid separation efficiency.

[0065] The above examples are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be used to limit the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. A gravity-fed pressure-stabilizing exhaust expansion tank for an engine cooling system, characterized in that, include: The water tank body has a coolant inlet on its side wall and a coolant outlet at its bottom. An exhaust pressure stabilizing unit is disposed on the upper part of the water tank body, including an exhaust chamber communicating with the interior of the water tank body, a piston that slides and seals with the inner wall of the exhaust chamber, a piston rod whose lower part is connected to the piston and whose upper part extends to the top of the exhaust chamber, and a counterweight assembly disposed on the upper part of the piston rod. The exhaust chamber has an exhaust port.

2. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 1, characterized in that: A guide component is fixed at the upper end of the exhaust chamber. The guide component has a guide groove that runs vertically through the chamber, and the piston rod passes through the guide groove.

3. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 1, characterized in that: The exhaust chamber is a cylindrical structure and is integrally formed on the upper part of the water tank body.

4. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 1, characterized in that: A limit nut is fixed to the upper part of the piston rod, and the counterweight assembly is sleeved on the piston rod with its lower end abutting against the limit nut.

5. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 4, characterized in that: The counterweight assembly includes several counterweight blocks stacked vertically.

6. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 1, characterized in that: The exhaust port is equipped with an upward-bent exhaust pipe.

7. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 1, characterized in that: It also includes a liquid level monitoring unit, which includes a liquid level gauge arranged along the height direction of the water tank body, a first connecting pipe connecting the lower part of the liquid level gauge to the lower part of the water tank body, and a second connecting pipe connecting the upper part of the liquid level gauge to the upper part of the water tank body.

8. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 7, characterized in that: The level gauge is a transparent tube with graduations on its outer wall arranged along the height of the water tank.

9. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 1, characterized in that: It also includes a pressure monitoring unit, which is a pressure gauge installed on the upper part of the water tank body, and the pressure measuring end of the pressure gauge is connected to the inside of the water tank body.

10. The gravity-pressure-stabilized exhaust expansion tank for an engine cooling system according to claim 1, characterized in that: It also includes a liquid replenishment unit, which includes a water inlet located at the upper end of the water tank body and a sealing cap that cooperates with the water inlet.

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