How do you say the accelerator in English?

The function of the valve is specially responsible for inputting air into the engine and discharging exhaust gas after combustion. From the engine structure, it can be divided into intake valve and exhaust valve. The function of the intake valve is to draw air into the engine and mix it with fuel for combustion; The function of the exhaust valve is to exhaust the exhaust gas after combustion and dissipate heat.

The valve consists of a valve head and a stem. The valve head temperature is very high (intake valve 570~670K, exhaust valve 1050~ 1200K), and it also bears the pressure of gas, the force of valve spring and the inertia force of transmission assembly. Its lubrication and cooling conditions are poor, which requires the valve to have certain strength, stiffness, heat resistance and wear resistance. Generally, the intake valve adopts alloy steel (chrome steel, nickel-chrome steel), and the exhaust valve adopts heat-resistant alloy (silicon-chrome steel). Sometimes in order to save heat-resistant alloy, the exhaust valve head is made of heat-resistant alloy and the valve stem is made of chromium steel, and then the two are welded.

The shape of the valve head includes flat top, spherical top and trumpet top. Generally, flat roof is adopted. The invention has the advantages of simple structure, convenient manufacture, small heat absorption area and light weight, and can be used for intake valves and exhaust valves. Spherical top valve is suitable for exhaust valve, which has high strength, low exhaust resistance and good exhaust elimination effect, but it has large heating area, large mass, large inertia and complicated processing. Horn type has a certain streamline, which can reduce intake resistance, but its head has a large heating area and is only suitable for intake valve.

Valve cone angle is the angle of valve sealing surface, which is generally 45, and some are 30 (CA10916 102 engine). Considering the same lift, the valve taper of 30 valve is small, the valve passing end face is large and the intake resistance is small. However, due to the thin edge of the valve head, small taper, low stiffness, poor sealing and thermal conductivity, it is generally used for intake valves. The thickness of the valve edge is generally 1~3mm to prevent the valve seat from being damaged or burned out at high temperature during operation. In order to reduce intake resistance and improve cylinder intake efficiency, the intake valve of most engines is larger than the exhaust valve. The used intake valve and exhaust valve have different colors.

The valve stem is cylindrical, it keeps reciprocating motion in the valve guide, and its surface must be heat treated and polished. The shape of the end of the valve stem depends on the fixed form of the valve spring. The common structure is to fix the spring seat with two locking pieces. At the end of the valve stem, there is an annular groove for installing the locking piece, and some of them are fixed with a locking pin, and the end of the valve stem has a hole for installing the locking pin.

The vowel letter A has a short vowel/? /,when pronounced, the tail of the tongue is close to the lower teeth, the front of the tongue is raised, and the tongue position is lower, which is the lowest among the four front vowels, but the one with the largest opening belongs to the short vowel. However, in actual pronunciation, it has a considerable length, the gums are between half-open and open, and the lips are not round. This sound appears in the prefix and position of words, such as:

Cushion cushion

Map map

Bag

Cat cat

Hat wide-brimmed hat

Fan Fan

racket

apple

I hope it can help you solve the problem.