Community self-service car washing machine scheme design

Through the analysis of the experimental data of the current portable car washing machine, it is found that the water consumption of the current car washing machine does not exceed 5L, and the motor pump is selected from the motor pump used to wash the front windshield of the car, so this energy-saving portable car washing machine can be simply modified. type, it can become a self-service car washing device equipped with the vehicle itself.

1. The composition of the experimental prototype

1.1 Selection of motor pump

The selection of the motor pump is a key step in the design of the car washer. The selected motor pump should meet the following requirements:

(1) The hydraulic pump used is a pressure compensation pump with adjustable flow. The pump's flow control matches the flow specification at which a nozzle of a given size produces the required discharge pressure, so no excess flow is generated.

(2) If the nozzle is blocked, the hydraulic pump is immediately in a state of zero flow, thereby protecting the system from overpressure.

(3) The power of the motor pump is relatively small, which matches the 12V power supply. Because the power supply is 12V power supply from the car, and the motor pump is used in the car washing system, the motor pump for washing the front windshield can be selected. The appearance size of the motor pump is 90×61×30 (length×width×height, unit mm), the inlet diameter of the pump is 9mm, the outlet diameter is 5mm; the power is 36W, and the resistance is 4.3Ω.

1.2 Nozzle

Nozzles are an important element of water jet equipment. Its function is to gather the pressure energy of high-pressure water through the shrinkage of the cross-section of the inner hole of the nozzle, and convert it into kinetic energy, and finally spray it out in the form of high-speed water jets for cleaning. From the perspective of effective jet operation and energy saving and consumption reduction, an ideal nozzle should meet the following requirements.

(1) The water beam sprayed by the nozzle should be able to effectively convert the pressure into the spray force on the jet surface.

(2) The nozzle has a small flow resistance, the sprayed water beam is less affected by entrainment, and can maintain the stability of the jet flow to facilitate the effect on the jet flow surface.

(3) Nozzles are not prone to clogging.

(4) Under the premise of ensuring a certain jet effect, reduce water consumption as much as possible.

1.3 Hoses

The outlet pressure of the nozzle is equal to the outlet pressure of the high pressure pump minus the pressure loss of the pressure water in the hose. Pipeline pressure loss is the main factor affecting the cleaning efficiency. Pipeline pressure loss is related to the diameter, length, inner surface roughness of the pipe and joint condition, and is the main part of the system pressure loss. The pressure loss of pressure water flowing in the hose can be calculated using the following two forms of formulas,

△p=59.7q2/ D15 Re0.25; △p=8λLq2/ gD15 where: △p——pressure loss of high-pressure water in the hose, Mpa;

D1—inner diameter of hose, mm; Re—Reynolds number of water, take 11165q/D;

λ——the drag coefficient along the way; L—the length of the high-pressure hose, mm.

2. Feasibility scheme of vehicle self-service car washing machine

2.1 Design concept of vehicle self-service car wash

At present, the on-board cleaning device on the automobile mainly includes the cleaning of the front windshield and the rear windshield, and on some cars, there is a cleaning device for the headlight. as shown in picture 2. Figure 2 The physical picture of the nozzle retractable headlight washer. This kind of headlight washer is directly installed on the car. Its characteristic is that the liquid reservoir of the front windshield is designed to be slightly larger than the liquid reservoir alone. Sharing a liquid reservoir with the windshield before washing is a good solution to achieve the purpose of two cleanings in the limited space of the car. Inspired by this idea, is it possible to directly install a car washer on the car, which not only makes up for the gap that the car washes itself, but also reflects the humanized design of the car.

2.2 Prerequisites for the realization of vehicle self-service car wash

As we all know, in the past, due to the relatively large water consumption required for car washing, it was difficult and unrealistic to place a large-volume liquid storage container in the limited space of the car. Now with the successful development of the energy-saving portable car washing machine, the water consumption for car washing has been greatly saved, and the water consumption is less than 5L. This volume is consistent with the viewpoint that the volume of the car washing device in literature [28] is 5-7L, so it can be Consider the development of a self-service car wash for vehicles. After the development of the energy-saving portable car washer, the following favorable prerequisites have been clarified for the development of the vehicle self-service car washer.

(1) The motor pump can share one with the motor pump for washing the front windshield.

(2) Because the water consumption is greatly reduced, the liquid reservoir can also share one with the liquid reservoir for washing the front windshield. With these two favorable conditions, the energy-saving portable car washer can become a car washer directly installed on the vehicle with a slight modification.

3. Design features of vehicle self-service car wash

The vehicle self-service car washing device effectively utilizes the existing resources on the vehicle, and better solves the problem of placing a car washing device in a limited space. It has the following characteristics.

(1) The power supply is also battery-powered, and it is usually not necessary to start the engine.

(2) The use of low-power motor pumps can save water resources.

(3) Using the liquid reservoir on the vehicle, the equipment does not need to be moved around.

4. Conclusion

This paper analyzes the possibility of a vehicle self-service car wash solution and introduces its basic design. The development of this car washer is a beneficial attempt to perfect the car washing function.