Machining process for ultra-thin special-shaped patterned ribs of all-steel tire mold

Abstract

The invention discloses a machining process for an ultra-thin special-shaped patterned rib of an all-steel tire mold, and relates to the technical field of pattern machining of all-steel tire molds, the machining process comprises the following steps: step 1, electrically marking a line at the position of the special-shaped patterned rib of a pattern ring, and forming an electrically-punched reference groove for a single-section frequency corrosion cavity material at the marked line by a graphite electrode; 2, the ultra-thin special-shaped patterned rib is machined in a 3D material increasing mode and embedded into a patterned rib base, and the width and the depth of the ultra-thin special-shaped patterned rib are kept consistent with the size of the single-section slotting electrode in the step 1; 3, a special auxiliary punch tool is manufactured, and pattern ribs are intact; and 4, spot welding, appearance finishing and surface strengthening treatment are conducted on the pattern and the seam of the cavity obtained in the step 1. The invention solves the problem that the existing method cannot realize the reverse buckling of multiple parts of complex pattern ribs, and shortens the processing period; and when the thickness of the patterned ribs is smaller than 0.8 mm, the machining quality is better, the patterned ribs are high in rigidity and fatigue resistance, the sintering phenomenon is avoided, the appearance quality of the patterned ribs is improved, and the service life of the patterned ribs is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of pattern processing of an all-steel tire mold, in particular to a processing technology for extremely thin special-shaped ribs of an all-steel tire mold. Background Art

[0002] Tire molds are molds used for vulcanization molding of various tires. They are important tools used in the tire vulcanization process. In the prior art, the processing of all-steel tire mold patterns generally adopts the electrospark forming process, which can complete the processing of conventional patterns. In recent years, as the design of all-steel tire patterns tends to be three-dimensional and complex, special-shaped ribs emerge in an endless stream, which further highlights some shortcomings of the electrospark forming process:

[0003] ① The spindles of existing three-axis electrode engraving and milling machines and EDM forming equipment can only move in a directional manner, which cannot meet the shape requirements of complex ribs with multiple undercuts;

[0004] ② When electro-punching very thin ribs, the electrode loss is large and sintering is easy. High current cannot be used, and the electro-punching efficiency is low and the processing cycle is long.

[0005] ③Electrospark forming will cause the surface of extremely thin ribs to become rough, cracked, and reduce fatigue strength, thus reducing the service life of tire molds;

[0006] ④ After the customer puts forward the demand for new mold products, the development cycle requirements are very urgent. How to realize the processing of extremely thin and special-shaped patterns and other difficult patterns, and how to shorten the processing cycle of patterns are technical problems that technical personnel in this field urgently need to solve.

[0007] Based on this, a processing technology for extremely thin special-shaped ribs of an all-steel tire mold is now provided, which can eliminate the disadvantages of the existing device. Summary of the invention

[0008] The purpose of the present invention is to provide a processing technology for extremely thin special-shaped ribs of an all-steel tire mold to solve the problems in the background technology.

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] A processing technology for extremely thin special-shaped ribs of an all-steel tire mold comprises the following steps:

[0011] Step 1: Electro-mark the position of the special-shaped ribs of the pattern ring, use the graphite electrode to take the marking as the positioning reference, and erode the cavity material in a single frequency to form an electro-marking reference groove;

[0012] Step 2: The ultra-thin special-shaped ribs are processed by 3D additive manufacturing. A special embedded rib base is added to ensure that there is a grinding margin at the junction of the two ultra-thin special-shaped ribs. The width and depth are consistent with the size of the single-section slotted electrode in step 1. The bottom chamfer of the rib base is used to prevent the fillet formed by electrode loss from interfering with the later embedding operation.

[0013] Step 3: During the embedding operation, the rib point is overloaded, and the extremely thin part of the rib is easily deformed and damaged. A special auxiliary punch tool is made, that is, an embedded punch is set to protect the extremely thin part of the rib from being stressed and keep it intact;

[0014] Step 4: Combine the above steps 1 and 2 into a complete cavity pattern. Perform spot welding on the joints to enhance the firmness of the ultra-thin special-shaped ribs and the tread block body. Trim the tread block to make the overall appearance of the pattern uniform.

[0015] Preferably, in step 1, the processing is performed using an electrospark forming device, and the embedded grooves of the extremely thin special-shaped ribs are electrocuted using standard parameters, which needs to be divided into rough processing, semi-finishing and finishing.

[0016] Preferably, before the 3D additive processing of the ultra-thin special-shaped ribs in step 2, the tread ring is processed into petals using a wire cutting device to become a single piece for the rib embedding operation.

[0017] Preferably, the auxiliary punch tool in step 3, i.e., the material and hardness of the embedded punch must be greater than that of the rib part.

[0018] Preferably, the embedded punch is made of 45# steel quenched and has a hardness greater than HRC55.

[0019] Preferably, in step 1, the dimensional error of the groove depth and width of the entire circle of the pattern is ≤0.05mm.

[0020] Preferably, in step 2, the length of the rib base is 0.2 mm.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention solves the technical problem that the existing molding process cannot realize multiple undercut surfaces of complex ribs through the combination of electric spark grooving, 3D additive manufacturing and subsequent embedding process, breaking the limitations of low efficiency and long cycle of traditional electric spark discharge, and greatly shortening the processing cycle of the pattern; when the thickness of the rib is less than 0.8mm, the processing quality is better than that of traditional discharge machining, the rib has strong rigidity and fatigue resistance, and the phenomenon of unstable sintering during the electric spark discharge process is avoided, which greatly improves the appearance quality and service life of the rib. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of step A1 of the present invention.

[0024] Figure 2 Schematic diagram of step A2 of the present invention.

[0025] Figure 3 A schematic cross-sectional view of the structure in step A2 of the present invention

[0026] Figure 4 Schematic diagram of step A3 of the present invention.

[0027] Figure 5 This is a complete cavity effect diagram assembled in step A4 of the present invention.

[0028] Figure 6 The present invention is a process flow chart of the ultra-thin special-shaped ribs of the all-steel tire mold.

[0029] Notes on the accompanying drawings: electric-punched reference groove 1, ultra-thin special-shaped rib 2, rib base 3, embedded punch 4. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0031] See also Figure 1-Figure 6 A processing technology for extremely thin special-shaped ribs of an all-steel tire mold comprises the following steps:

[0032] Step 1: Electro-mark the position of the special-shaped ribs of the pattern ring, use a graphite electrode to use the marking line as a positioning reference, and erode the cavity material in a single-section frequency to form an electro-marking reference groove 1;

[0033] Step 2: The ultra-thin special-shaped ribs 2 are processed by 3D additive manufacturing, and a buried rib base 3 is specially added to ensure that there is a grinding margin at the joints between the ultra-thin special-shaped ribs 2. The width and depth are consistent with the size of the single-section slotted electrode in step 1. The bottom chamfer of the rib base 3 is used to prevent the fillet formed by electrode loss from interfering with the later embedding operation.

[0034] Step 3: During the embedding operation, the rib point is overloaded, and the extremely thin part of the rib is easily deformed and damaged. A special auxiliary punch tool is made, that is, an embedded punch 4 is set to protect the extremely thin part of the rib from being stressed and keep it intact;

[0035] Step 4: Combine the above steps 1 and 2 into a complete cavity pattern. Spot weld the joints to enhance the firmness of the ultra-thin special-shaped ribs 2 and the pattern block body. Trim the pattern block to make the overall appearance of the pattern uniform.

[0036] See also Figure 1In step 1, the processing adopts the electric spark forming equipment, and the embedded groove of the ultra-thin special-shaped flower rib 2 is electrocuted using standard parameters, which needs to be divided into rough processing, semi-finishing and finishing.

[0037] See also Figure 2-Figure 3 Before the 3D additive processing of the ultra-thin special-shaped ribs 2 in step 2, the tread ring is processed in petals using wire cutting equipment to become a single piece for rib embedding operation.

[0038] See also Figure 4 The auxiliary punch tool in step 3, that is, the material and hardness of the embedded punch 4 must be greater than the rib part, and can continuously withstand the impact force of the embedding operation to prevent the embedded punch 4 from being worn, twisted, or the reference is lost, resulting in poor rib embedding effect.

[0039] See also Figure 2-Figure 3 The embedded punch 4 is made of 45# steel and quenched, and its hardness is greater than HRC55.

[0040] See also Figure 1 In step 1, the dimensional error of the groove depth and width of the entire circle of the pattern is ≤0.05mm.

[0041] See also Figure 2-Figure 3 In step 2, the length of the rib base 3 is 0.2 mm.

[0042] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A processing technology for extremely thin special-shaped ribs of an all-steel tire mold, characterized in that: The following steps are involved: Step 1, the position of the special-shaped rib of the pattern ring is electrically marked, and a graphite electrode is used to take the marked line as a positioning reference, and the cavity material is corroded in a single frequency to form an electrically marked reference groove (1); Step 2, the ultra-thin special-shaped ribs (2) are processed by 3D additive manufacturing, and a buried rib base (3) is specially added to ensure that the ultra-thin special-shaped ribs (2) have grinding and polishing margins at the joints, and the width and depth are consistent with the size of the single-section slotted electrode in step 1. The bottom chamfer of the rib base (3) is used to prevent the fillet formed by electrode loss from interfering with the later embedding operation; Step 3: During the embedding operation, the rib point is overloaded, and the extremely thin part of the rib is easily deformed and damaged. A special auxiliary punch tool is made, that is, an embedding punch (4) is set to protect the extremely thin part of the rib from being stressed and keep it intact; Step 4: The above steps 1 and 2 are combined into a complete cavity pattern. The joints are spot-welded to enhance the firmness of the ultra-thin special-shaped ribs (2) and the pattern block body. The pattern block is trimmed to make the overall appearance of the pattern uniform.

2. The processing technology of the ultra-thin special-shaped ribs of the all-steel tire mold according to claim 1 is characterized in that: In the step 1, the processing is carried out using an electrospark forming device, and the embedded groove of the extremely thin special-shaped rib (2) is electrocuted using standard parameters, which needs to be divided into rough processing, semi-finishing processing and finishing processing.

3. The processing technology of the ultra-thin special-shaped ribs of the all-steel tire mold according to claim 1 is characterized in that: Before the 3D additive processing of the ultra-thin special-shaped ribs (2) in step 2, the tread ring is processed into petals using a wire cutting device to become a single piece for the rib embedding operation.

4. The processing technology of the ultra-thin special-shaped ribs of the all-steel tire mold according to claim 1 is characterized in that: The auxiliary punch tool in step 3, i.e. the embedded punch (4), must be made of a material and have a hardness greater than that of the rib part.

5. The processing technology of the ultra-thin special-shaped ribs of the all-steel tire mold according to claim 4 is characterized in that: The embedded punch (4) is made of 45# steel and quenched, and has a hardness greater than HRC55.

6. The processing technology of the ultra-thin special-shaped ribs of the all-steel tire mold according to claim 4 is characterized in that: In step 1, the dimensional error of the groove depth and width of the whole circle of the pattern is ≤0.05mm.

7. The processing technology of the ultra-thin special-shaped ribs of the all-steel tire mold according to claim 4 is characterized in that: In step 2, the length of the rib base (3) is increased to 0.2 mm.

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