Chongqing Songyo Auto Parts Co., Ltd.

There are multiple classifications of automotive automotive equipment There are mechanical devices, air breathing apparatus, straws, retractable devices, etc.   What we are going to explain today is the mechanical maintenance device. There are also sub-items in the mechanical maintenance device that are daily maintenance devices and maintenance devices.   Let me explain to you what is the difference between the two of them Hydraulic device The oil is used for high-speed transmission, through the cylinder oil and the inner oil of the hole wall to generate force, but it forms an impact on the body, forming a continuous and working on the body, which is prone to atomization, making the user unable to work However, the expected effect is not achieved. At low temperatures, the viscosity of the oil continuously pursues the performance of the hunter; during continuous operation, the oil flow of the aircraft during continuous operation will make a noise and generate its own sonic noise. Inflatable shock absorber The gas-filled shock absorber is also called the oil-gas hybrid shock absorber. It uses oil as the medium and adds part of the gas in the cylinder as an auxiliary. The gas medium is added on the basis of hydraulic shock absorption, which increases the stability and reduces The noise caused by the high-speed flow of oil, but the working principle is still the working principle of hydraulic shock absorption. How do we distinguish between hydraulic shock absorbers and pneumatic shock absorbers (there is no difference in appearance)   I’m here to share my own judgment skills, provided that the shock absorber is not faulty. After unpacking the shock absorber, if the piston rod of the shock absorber is not extended without any fixing device, it is an air-filled shock absorber, and if the piston rod does not extend, it is a hydraulic shock absorber.   Reminder: Some brands of shock absorbers have a self-locking function for the convenience of packaging and transportation. That is, before installing the shock absorber, you need to rotate the piston rod with a tool before the piston rod pops out.   Why do I distinguish between pneumatic and hydraulic shock absorbers in this way? The reason is this When the inflatable shock absorber is assembled, the piston rod is extended. At this time, the inside of the shock absorber has just reached the balance of force. When compressed in, the gas will be compressed, destroying the balance of force. When the piston rod is not compressed, the compressed gas will return to its original shape, which will push the piston rod to rebound and regain the balance of force. But the hydraulic shock absorber is different because there is no gas in it, only liquid, and there is still The built-in spring, the piston rod is stretched inside when assembling. When you pull it out and let go, the spring will force the piston rod to retract. At the same time, because of the rapid pull out, the hydraulic oil has not all been reduced from the working cylinder. Flowing into the working cylinder with increased volume, this force will also force the piston rod to retract, but it usually does not retract to the original position because part of the hydraulic oil flows into the working cylinder with increased volume.   Reminder: Some inflatable shock absorbers also have a built-in spring inside. When the piston rod moves up, it will press this spring. The spring will buffer and improve comfort. Hydraulic shock absorber do not rebound Inflatable shock absorber      Reminder: So in the future, if the piston rod of the shock absorber does not rebound, it may not be the quality problem of the shock absorber. Maybe this shock absorber is a hydraulic shock absorber.

Harsh winter weather and new-car supply constraints should help prospects for auto-parts retailers Auto-parts retailers look revved up and ready to go. Their share prices have some catching up to do. O’Reilly Automotive, ORLY 1.89% which held its earnings call Thursday morning, saw record quarterly sales and earnings. The auto-parts retailer reported a 25% revenue jump for the first quarter compared with a year earlier, well above the 14.7% analysts polled by Visible Alpha expected. Net income rose 67%. The coronavirus pandemic reduced traffic levels to unusual lows last year, but that barely scuffed auto-parts retailers’ top lines. O’Reilly’s 2020 sales increased 14.3%, a substantial jump compared with the 7.1% growth it saw on average over the preceding five years. For the 12 months ended Feb. 13, AutoZone AZO 1.60% saw its revenue grow 10.9%, more than double the five-year average growth rate. The concern is this growth may not be sustainable. Auto-parts retailers say they aren’t writing off the possibility that demand last year was pulled forward as consumers received stimulus checks and had more time at home to pursue do-it-yourself projects. Yet there are plenty of conditions that could yield surprising sales bumps. For one, traffic still isn’t back to pre-pandemic levels. Once more cars return to the road, it is likely that there will be a rotation in the categories that perform well. AutoZone had noted that brakes and rotors weren’t selling as well in its most recent fiscal quarter because cars were on the road less; that should come back as traffic recovers fully. The harsh winter weather seen earlier this year should mean more maintenance and repairs are needed on many vehicles, which could help boost sales throughout this year after two consecutive years of mild winters, O’Reilly said during its earnings call.

In recent years, almost all vehicles on the market use injection fuel supply systems. The main reason is that they have to respond to increasingly stringent environmental regulations. The fuel injection system has evolved from the early mechanical single-point injection to the current electronic multi-point injection. Then, what are single-point injection and multi-point injection? Assuming a four-cylinder engine, from a single injector to the branch of the intake manifold, the fuel is injected from one place and then distributed to the four cylinders with the intake air. This is a single point injection; In the intake port of each of the four cylinders, because each cylinder has one fuel injection nozzle, the four-cylinder engine has four fuel injection nozzles. This is called multi-point injection.   From the perspective of the fuel path, first, the fuel pump sends the fuel from the fuel tank to the fuel pipeline, and the fuel pipeline sends the fuel to the fuel rail. The fuel rail is controlled by the pressure regulating valve to control the fuel pressure and ensure the fuel delivered to each cylinder. The pressure can all be the same. On the other hand, the pressure regulating valve will also send excess oil to the oil return pipe and flow back into the oil tank by releasing the pressure. One end of the fuel injection nozzle is connected to the fuel rail, and the nozzle is on the air inlet of each cylinder. The engine ECU will issue a fuel injection command to the fuel injector according to the engine operating status. The fuel injection quantity is determined by the fuel pressure and the fuel injection time of the fuel injector. The fuel pressure at the fuel rail is controlled by the pressure regulating valve, and the fuel is regulated. The pressure of the pressure valve is adjusted by the manifold vacuum (engine load), so the ECU can control the fuel injection time. When the engine needs more fuel, the fuel injection time will be longer, otherwise the fuel injection time will be shorter.   The injector itself is a normally closed valve (normally closed valve means that the valve is always closed when there is no input control signal; while the normally open valve is the valve is always open when no control signal is input). A valve needle moves up and down to control the opening and closing of the valve. When the ECU issues a fuel injection command, its voltage signal will cause current to flow through the coil in the fuel injection nozzle, generating a magnetic field to suck up the valve needle, and open the valve so that the fuel can be ejected from the fuel injection hole.   The biggest advantage of fuel injection is that the control of fuel supply is very precise, allowing the engine to have the correct air-fuel ratio in any state. Not only does it keep the engine running smoothly, but its exhaust gas can also comply with environmental regulations.

Answer:Failure of the shock absorber will increase the braking distance I will not explain the working principle of the shock absorber in detail here. To put it briefly, it is to convert the elastic potential energy of the automobile spring vibration into heat energy, so as to achieve the purpose of attenuating the frequency and amplitude of the spring vibration. From this principle, we can also draw a judgment method for judging whether the shock absorber is invalid: that is, after the vehicle has been running for a period of time, touch the barrel of the shock absorber by hand, and if there is heat, the shock absorber It has not completely failed. On the contrary, it means that the shock absorber has failed and needs to be replaced in time. With the above foreshadowing, let’s analyze together why the failure of the shock absorber will cause the braking distance to become longer. We know that when braking, the friction between the tire and the ground is used to slow down or stop the car. If the shock absorber fails, the vibration frequency and amplitude of the car spring will increase, resulting in a reduction in the effective contact area between the tire and the ground. The tire grip is reduced, and the failure of the shock absorber will cause the center of gravity of the car to move forward seriously when braking. Because there is no support of the damping force of the shock absorber, the front wheel damping system is soft, so it will cause the center of gravity to move forward. Due to the failure of the shock absorber of the front wheel, the compression force of the spring will be very large. The greater the compression force, the greater the rebound force, which will cause the vibration frequency and amplitude of the spring to further increase. The effective contact area is smaller and the tire grip is worse. In addition, the forward movement of the center of gravity will also cause the rear of the car to tilt, resulting in a reduction in the contact area between the rear tires and the ground, and a reduced grip. The superimposition of the front and rear tires will eventually cause the braking distance to be extended.   Supplementary knowledge:   How to judge whether the shock absorber has failed (without oil leakage) 1. Press the car body to the lowest point with your hand, and then quickly let go. If the car body jumps up and down more than 2 times with a large amplitude, it means that the shock absorber may fail and further analysis is required 2. Remove the shock absorber and check whether the damping force of the shock absorber is normal: hold both ends of the shock absorber with your hand to pull the shock absorber several times, and keep the shock absorber in the installed state during this process In the same posture, if the shock absorber has a stable damping force, it means that the shock absorber is good and has not failed; if the damping force of the shock absorber is unstable or there is obviously no resistance, it can be judged as a failure   3. When the car stops after driving on a bad road for a certain distance (generally more than 10Km is appropriate), touch the outer surface of the shock absorber oil tank with your hands. If the temperature of the shock absorber oil tank is not higher than the neighboring oil tank, it will not generate heat. Parts (such as springs) indicate that the shock absorber has failed. If the cylinder temperature of the left and right shock absorbers is high and the other is low, and the temperature difference between the left and right shock absorber cylinders is relatively large, it indicates that the performance of the low-temperature shock absorber has degraded or the shock absorber has failed. If the shock absorber has leaked oil, you need to look at the specific severity of the oil leak. If the oil has spread all over the barrel, it is recommended to replace the shock absorber with a new one as soon as possible. If there is only a slight oil leak or the leaking area is not wet In the case of this, please consult a professional repair shop master.