Vacuum pump with reduced risk of failure

Abstract

The utility model relates to the field of automobile manufacturing, concretely relates to a vacuum pump of reducing failure risk, the utility model discloses a winter northern extremely cold region frequent low-speed low load use scene under the problem of vacuum pump failure, the reason is analyzed: northern low temperature area, 35~‑25 DEG C ambient temperature, the water component in oil is more and freezes, and the rotation resistance of vacuum pump increases and locks, through the slotting of oil drain, the residual amount of vacuum pump oil can be reduced, and the failure of vacuum pump can be effectively reduced. And determine the slotting of pump body oil drain, and the slotting size is 2*2mm, and the groove depth is 1mm, and through overall test, spare part function test, spare part endurance, engine bench endurance, vehicle function test etc. can satisfy each requirement.

Description

Technical Field

[0001] This utility model relates to the field of automobile manufacturing, specifically to a vacuum pump that reduces the risk of failure. Background Technology

[0002] Vacuum pumps, as key automotive components, provide a stable and continuous vacuum source for systems requiring vacuum control (such as vacuum-assisted braking systems, turbocharger systems, and EGR systems), effectively ensuring the normal operation of the engine and the driving safety of the vehicle. Currently, industry-standard vacuum pump designs meet automotive functional requirements, but in certain special usage scenarios and operating conditions, such as in extremely cold regions during winter in northern China, or in frequent low-speed, low-load usage scenarios, vacuum pumps face the risk of failure. Utility Model Content

[0003] To address the aforementioned problems, this utility model proposes a solution for vacuum pump failure under frequent low-speed, low-load operation scenarios in extremely cold northern regions during winter. The specific technical solution is as follows: A vacuum pump with reduced failure risk has a groove in the oil drain port of the pump body, the groove size is 2*2mm and the groove depth is 1mm.

[0004] Analysis confirmed that in low-temperature regions of northern China, at ambient temperatures of 35 to -25°C, the oil contains a high amount of water, which freezes, increasing the rotational resistance of the vacuum pump and leading to its failure. Reducing the amount of residual oil in the vacuum pump by slotting the oil drain port can effectively reduce the likelihood of vacuum pump failure. Attached Figure Description

[0005] Figure 1 A schematic diagram of a vacuum pump structure in the prior art; Figure 2 A schematic diagram of the structure of this utility model; Figure 3 Example 1: 1500h high and low temperature durability test conditions. Detailed Implementation

[0006] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example

[0007] Failure mode and cause analysis for a certain vacuum pump: Failure mode: Vacuum pump failure in extremely cold northern regions during winter, under low-speed and low-load operating conditions, resulting in abnormal engine noise; in severe cases, the VVT ​​plug slips, causing the vehicle to fail to start. Operating conditions: Short-distance commuting within 10km, low speed and low load, insufficient vehicle warm-up, and increased oil dilution; Operating environment: Extremely cold weather of -35~-25℃, causing diluted oil to freeze after shutdown, leading to vacuum pump failure.

[0008] By adopting the structure of this utility model, a groove is cut into the oil drain port of the original vacuum pump body. The groove size is 2*2mm, and the groove depth is 1mm. For example... Figure 1 For the original vacuum pump, Figure 2 This is a vacuum pump designed with slotting.

[0009] Validation of the optimization scheme: 1) On-vehicle test of residual oil in slotted vacuum pump Test method: After the vehicle has warmed up, shut down the machine. Replace the vacuum pump with a transparent cover, start the vehicle, idle for 2 minutes, then turn off the engine and let it stand for 30 minutes. Record the residual oil level in the slotted vacuum pump.

[0010] Actual on-vehicle testing showed that after the oil drain port was grooved, the residual oil level decreased by about 53%, a significant improvement; and the residual oil level remained basically the same regardless of the angle at which the vane stopped.

[0011] 2) Verification and evaluation criteria for the optimization scheme: Once the optimization plan is finalized, it needs to undergo a series of verifications, including component functional testing, component durability testing, engine bench durability testing, and whole vehicle functional testing, before it can be finally approved for mass production. The following procedures are generally recommended: Component functional testing: Meets the vacuum pump's vacuuming capacity requirements for the braking system (375 rpm, 4.559 L air tank volume, 5W-30 engine oil), for example: Component durability: 1500h high and low temperature durability, test conditions refer to Figure 3 ; Engine bench durability: 280hEFT durability, test conditions refer to national standards; Vehicle functional testing: Vehicle braking test BR-1094: The vacuum performance curve must be above the BR-1094 standard curve. BR-1071: When the vehicle is idling stationary, the brake pedal should be pressed at 2.5-second intervals, with the pressing process completed within 1 second. The vacuum level of the vacuum booster must not be lower than the vacuum level corresponding to the booster inflection point at a vehicle deceleration of 3.2 m / s². Furthermore, the impact of the optimization scheme on vehicle fuel consumption and vehicle NVH (noise, vibration, and harshness) must be comprehensively evaluated.

[0012] After adjustment, the vacuum pump of this utility model can meet the above-mentioned working conditions and evaluation requirements.

[0013] The preferred embodiments of this patent have been described in detail above. However, this patent is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this patent.

Claims

1. A vacuum pump with reduced failure risk, characterized in that: The pump body has a slotted oil drain port with a size of 2*2mm and a depth of 1mm.

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