Spring Wire Expert —— Meng Ao Electronic Technology
1. Scope of application:
It is suitable for the operation design of spring wire (no special fixture is used to shape the spring), except for special types of spring wire.
2. Contents:
2. 1. 2. 1. 1. Winding direction: according to the spring direction, it can be divided into first positive and then negative, first negative and then positive. When the winding direction of the spring is S direction (as shown in Figure A), the spring is wound first and then reversely; (Note: the general direction of the steel wire is Z) When the winding direction of the spring is Z (as shown in Figure B), it is wound in the reverse direction first and then in the forward direction. (Note: The general direction of the wire is S)? 2. 1.2. Diameter of iron bar: Select the appropriate iron bar according to "Diameter of iron bar = outer diameter of spring -2 times outer diameter of steel wire".
2. 1.2. 1. Common bar specifications are: φ5.0mm, φ6.0mm,? φ6.35mm，φ7.0mm，？ φ8.0mm，？ φ9.0mm，？ φ 1 1.0mm，？ φ 12.0mm，？ φ14.0mm
2. 1.2.2. The diameter of the iron bar corresponds to the length of the spring body as follows:?
2. 1.3. Positioning length: It depends on the specific shear size of the shortest spring line and its final specific shear size. Generally 120 mm or less, the positioning length is150mm; 120mm or more, the positioning length is "the shortest specific shear size+30mm"; The tolerance of positioning length is designed to be 25mm.
2. 1.4. Length and tolerance of winding spring: according to the final spring length specification and wire material.
2. 1.4. 1. Overall design principle: spring length: outer materials: high-elastic PVC and TPE? (conductor bare copper) sleeve length = spring length specification x1.15+10mm; ? External materials PU and TPE? (Conductor tin and copper) Sleeve length = spring length specification x 1. 1+ 10 mm? Tolerance: set to 10 mm?
2. 1.4.2. The requirements on the dimensions of finished products are harsh (such as small tolerance, long elastic body and large outer diameter), or the wire structure is special (such as large outer diameter, PVC core material and copper foil/nylon rope structure), which should be adjusted according to the actual situation. 2.2. Drying line: oven temperature, holding time and cooling mode are set according to wire material.
2.2. 1. General design principles:? Iron bar diameter? The length of the iron bar? Maximum winding length? 820mm？ 7 10mm？ φ6.0mm？ 14 10mm？ 1300mm？ 820mm？ 7 10mm？ φ8.0mm？ 1360mm？ 1250mm？ Other? 820mm？ 7 10mm？ What is the outer material? Oven temperature setting? Heat preservation time setting? Cooling method PVC? 130 10℃? 20 5 minutes? Air cooling? Pu? 140 10℃? 25 5 minutes? Water cooling? TPE？ 150 10℃? 40 5 minutes? Air cooling or water cooling?
2.2.2. The flexibility required by customers is strict. Consider the outer diameter of the spring, the length of the elastomer, and the wire structure or the wire structure itself (such as the aging situation or material of the core wire and the outer sheath, the oxidation of bare copper at high temperature, the heat shrinkage of copper foil/nylon wire/nylon rope, the thickness of insulation/outer sheath, etc.). ), the corresponding parameters need to be adjusted according to general principles (such as reducing/increasing baking temperature, prolonging holding time and being flexible).
2.3. Secondary winding:? 2.3. 1. Take the primary winding and use the opposite direction for the secondary winding. Choose iron bars according to the primary winding. Under special circumstances, a slightly smaller/larger iron bar can be used for winding. 2.3.2. Ensure the length and outer diameter of the spring: In order to prevent the size of the spring wire from exceeding the specification due to being involved in the assembly process of the finished product, the guaranteed size of the cable winding part should be less than the specification tolerance of the finished product drawing 15%, and the spring wire parts should be manufactured according to this principle. Drawing tolerance (that is, the specifications provided by customers are sometimes not correct, and engineers should communicate with customers). ? 2.3.3. Determination of spring length tolerance: In order to reasonably determine the spring tolerance and meet the process capability, the following principles are adopted without violating the customer specifications and the principle of 2.3.2, which is also applicable to the process capability reference of spring length tolerance.
2.4. Right-angle baking: When the finished product drawing requires that both ends of the spring should be baked at a right angle of 90℃.
2.5. Comparison scissors at both ends: the size of comparison scissors is provided by the customer and verified. Note that for the comparison scissors at both ends of non-baked right-angle spring wire, the winding engineering specification should give the dimensions including the outer diameter of the spring (so as to facilitate the operation of the cable department and not inadvertently cause the error of comparison scissors); Baked at right angles can give the size of the straight parts at both ends.
2.6. Quality inspection of semi-finished products: a. Appearance: no appearance defects such as cracking, deformation and bell mouth. B the specific shear size of the head and tail and the size of the spring part must meet the requirements. C. If the outer cover is white or light gray, the line wiping process should be added. In order to prevent the shell of the wire from getting dirty, it should be kept clean.
2.7. Packaging method: The design principle is to protect the spring wire in addition to meeting the requirements of the finished product drawing. When there is no requirement, the packaging method is designed as follows: every six springs are tied with a PVC-coated spring and wrapped with a PVC film; Every 10PCS, tie a spring covered with PU and TPE and wrap it with PVC film. Note: total length of spring wire = specific shear size of end A+specific shear size of end B+π (spring body OD- wire OD) spring body length/wire OD+.
Meng Ao electronic technology-spring si experts