Function and quality requirements of pressure plate spring

It has special function of wire rod and pressure plate, and also has special technology of making spring. The function of the pressure plate spring is to use its tension to press the clutch pressure plate and clutch plate tightly on the wheel, so that the power of the engine can be reliably transmitted to the transmission system.

The quality requirements for making pressure plate spring are as follows:
1. Material: pressure plate spring material is 65Mn steel wire or group I and II carbon spring steel wire.
2. Appearance quality requirements: the surface quality of the finished spring should be smooth without cracks, oxide skin, rust and other defects. The cold coil spring is not allowed to have individual indentation, dent and scratch with depth exceeding half of the material diameter tolerance.
3. Hardness: after quenching and tempering, the hardness value of cold coil spring should be in the range of 44-52hrc. Under special circumstances, the selection range of hardness value can be extended to 55HRC.
4. Processing density
a. The surface roughness of spring should not be less than 12.5 μ M.
b. The flattened part of the supporting ring of compression spring with both ends tightly ground shall not be less than 3 / 4 of the circumference of the circle, and the thickness of the end shall not be less than 1 / 8 of the diameter of the steel wire. For the spring with flat ends, the thickness of the end shall not be greater than 1 / 3 of the diameter of the steel wire, and the width shall not be less than 70% of the diameter of the steel wire.
c. According to the use requirements, the nonuniformity of spring pitch can be checked. The tolerance is 10% of the spacing, and the minimum tolerance is generally 0.3mm. When the compression spring is compressed to 80% of the total deformation, the spring coil with normal pitch is not allowed to contact.
d. The perpendicularity tolerance between the two ends of the compression spring and the spring axis line is 2.5% of the free height, and the minimum tolerance is 1 mm.
e. The straightness tolerance of axis line of compression spring is half of perpendicularity tolerance.