When designing the valve spring, the vibration generated should be minimized, and the natural frequency of the spring is an important parameter.
The transition from the positive inertial force of the spring to the negative inertial force of the spring fluctuates the most, and the detachment of the system is most likely to occur. The spring force should exceed the inertial force of the system vibration, and there is a certain amount of wealth. G has equal point is the spring length of the horizontal line to the corresponding vertical line, the inertial force obtained on the inertial force diagram curve. The load characteristic curve of the spring should be high enough, and the load generated by the vibration reduction is still greater than the inertia load; when the engine is at the maximum speed, the valve system does not detach; the spring has sufficient load to close the valve without generating valve rebound; The elastic force should be 30% larger than the inertial force.
In order to overcome the above effects, most of the valve springs of automobile and motorcycle engines adopt variable pitch springs. The variable pitch springs are divided into: one end variable pitch valve springs: the pitch increases from one end to a certain value and becomes a pitch spring; Variable pitch valve spring: The pitch increases from both ends, and the pitch is a symmetrical valve spring.
With the improvement of the performance of automobiles and motorcycles, the valve spring material is required to have high tensile strength, good heat resistance and strong anti-relaxation force. The oil-quenched alloy spring steel wire used is a small amount of silicon steel, chromium, and cold-drawn into a carbon steel, and then continuously quenched and tempered. Its surface defects, such as dents, strains, decarburization and non-metallic inclusions, can affect the life of the valve spring. Japan has established standards for surface dents and strains. At present, it has developed better oil-hardened steel wires, which have slightly changed the composition of silicon and chrome steel. The tensile strength can reach 2100N, and a small amount of nickel can be added to crack propagation. The speed is slower. Commonly used valve spring materials are 50CrVA, 60SiZCIA, 60SiZCrVA, 55Crsi and the like. Due to the fatigue damage of the valve spring, there is now a design of the profiled valve spring wire. A is an oval section composed of a circle and a straight line, B is a circular section, C is an oval section composed of several arcs, and D is an elliptical section composed of a rotation curve. Japan's new engine is widely used in the production of valve springs with special-shaped cross-section (ellipse and egg type) oil quenched alloy spring steel wire. It should be noted that when winding the spring, special adjustable angle guide wire plate, coil spring pin and other tooling are used. To ensure the accuracy of the winding, the special tool for spring application is manufactured to check the cross section. The surface hardness of the valve spring soft nitriding is above 90Hv. If the internal hardness is lower than 0.05, the shot peening and heat setting technology should be adopted after spring molding, which mainly ensures the spring has good durability.
1.with 3000 square meter factory about 35 workshop workers and 25 office workers.
2.More than 20 sets of advanced machines with more than ten years domestic trade experience and international trade experience.
3.Manufacture and supply good quality automatic doors
4.With ISO 9001 Certification and many others certifications
5. Excellent DC brushless motor , high wear-resistant qualities wheels and reasonable structure design makes it more stable, quiet, longer life
6.Our Service system is perfect
Controller Dimensions : 85×124×600mm
Weight :12 kg
Maximun leaf weight :150 kg
Open range : 70°~115°
Closing speed : 10~43 cm/s
Door hold time :0.5~10 seconds
Main Power :AC 220V~250V,50~60 Hz
Maximum current :1A
Maximun motor power:55W
Wait Power :14W
Fuse :Minimum 3.5 ASlow
Operating Temperature : -30℃ ~+50℃
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