Forming process and forming system of aluminum alloy synchronous belt pulley

Abstract

The invention provides a forming process and a forming system for an aluminum alloy synchronous belt pulley, and the forming process comprises the following steps: S1, high-temperature aluminum drawing: heating an aluminum alloy blank at a high temperature to soften the aluminum alloy blank, and manufacturing an aluminum alloy profile with an inner hole in the middle and teeth on the peripheral surface through an extruding machine; wherein the tooth surface structure of the aluminum alloy profile with the teeth on the peripheral surface is smaller than a standard tooth forming structure; s2, bar measuring and slitting, wherein the mass or volume needed by a product is measured, and the aluminum alloy profile is slit to form a plurality of tooth forming blanks; the tooth forming blank is extruded through a press machine, and finally a belt pulley die with the surface wall thickness is formed at the bottom face end of the tooth forming blank, and the periphery of the tooth forming blank forms a standard tooth shape; and S4, machining is conducted, specifically, auxiliary machining such as cleaning, trimming and chamfering is conducted on the belt pulley die, and the aluminum alloy synchronous belt pulley is formed. The invention further provides a forming system of the aluminum alloy synchronous belt pulley, and the forming system comprises an extrusion forming system, a modeling and slitting system, an upsetting forming system and a machining system.

Description

Technical Field

[0001] The invention relates to a forming process and a forming system for an aluminum alloy synchronous pulley. Background Art

[0002] Synchronous pulleys are mechanical components used to transmit power and motion and are widely used in industrial automation, automotive, textile, agricultural machinery, and other fields. Key technologies for synchronous pulleys include tooth profile design, material selection, and manufacturing processes. Tooth profile design typically adheres to international or industry standards, such as DIN and ISO, to ensure compatibility between synchronous belts and pulleys produced by different manufacturers and achieve standardized parameters.

[0003] At present, the manufacturing process of synchronous pulleys includes a variety of technologies such as precision casting, CNC machining, laser cutting, and stamping. High-precision CNC machine tools are widely used in the tooth processing of synchronous pulleys to ensure the accuracy and consistency of the tooth profile. Material surface treatment technologies such as heat treatment, electroplating, and spraying are also used to improve the wear resistance and corrosion resistance of synchronous pulleys. Among them, the wheel body and tooth forming of aluminum alloy pulleys are two important aspects of synchronous pulley manufacturing, which directly determine the quality and feasibility of manufacturing. The forming method of aluminum alloy structures can be selected according to the size, shape, performance requirements and production batch of the parts. Common methods include casting, pressure casting, forging, extrusion, machining, etc. The forming process of aluminum alloy parts needs to be selected according to the specific application requirements and production conditions to achieve the best cost-effectiveness and product quality. In addition, tooth processing is a complex process that requires precise equipment and process control to meet higher precision and efficiency requirements.

[0004] At present, the company adopts the traditional mechanical processing method. The main process route is to cut the aluminum alloy bar, then process the outer diameter, end face and inner hole of the blank on the CNC lathe, and then change the machining center to mill the tooth shape (here the gear hobbing machine can also be used), and finally process the chamfer, deburring and other surface treatments (products such as Figure 7 As shown in the figure, it has the limitations of low processing efficiency, high processing cost, long process flow, etc., and has the following disadvantages:

[0005] 1. Production efficiency is not high enough, especially when processing tooth shapes, which requires multiple layers of repeated milling operations. The working hours are long and limited by the number of machining centers. In addition, because multiple processes require the use of different machine tools, they also need to be clamped, moved, and adjusted on different machine tools.

[0006] 2. The cost of processing equipment is high, and the material removal rate is high, which easily leads to material waste.

[0007] 3. Heat is easily generated during the processing, affecting material properties.

[0008] 4. There is a certain demand for cutting tools and coolants, and the processing process generates a large amount of waste chips, which increases the site processing cost. Summary of the Invention

[0009] The purpose of the present invention is to overcome the above-mentioned defects. The inventors found in the process of repeated experiments that the process of directly using high-temperature aluminum drawing to form standard teeth in one step has poor precision of the stretched profile due to factors such as thermal expansion and contraction deformation, extrusion pressure, etc., and a bottoming process is also required; while the inventors directly use cold forging to form standard teeth in one step of the blank, which has the problems of high cold forging pressure, uneven material flow, high probability of fission, and easy jamming during stripping. The present invention provides a forming process and forming system for an aluminum alloy synchronous pulley.

[0010] The present invention adopts the following technical solutions:

[0011] A forming process for an aluminum alloy synchronous pulley comprises the following steps:

[0012] S1, high-temperature aluminum drawing: heating the aluminum alloy billet at high temperature to soften it, and forming it into an aluminum alloy profile with an inner hole in the middle and teeth on the outer peripheral surface through an extruder; wherein the tooth surface structure of the aluminum alloy profile with teeth on the outer peripheral surface is smaller than the standard tooth structure.

[0013] S2, bar measurement and cutting: Calculate the mass or volume required for the product and cut the aluminum alloy profile into multiple toothed blanks.

[0014] S3, upsetting forming: the tooth blank is extruded by a press, and finally the bottom end of the tooth blank is formed into a pulley mold with a thick wall and a standard tooth shape at the periphery.

[0015] S4, machining: perform auxiliary machining such as smoothing, edge removal, and chamfering on the pulley mold to form an aluminum alloy synchronous pulley.

[0016] Preferably, in step S1, it also includes an aluminum drawing die; the aluminum alloy billet is heated at high temperature to soften it, and is made into an aluminum alloy profile with a hole in the middle and teeth on the outer peripheral surface through the extruder and the aluminum drawing die.

[0017] Preferably, in step S2, the mass or volume required for the product is calculated by modeling simulation software, and the aluminum alloy profile is cut into a plurality of tooth blanks.

[0018] Preferably, in step S3, the press is a hydraulic press, and the punch of the hydraulic press is slightly larger than the inner hole of the tooth blank. During upsetting, the hole wall margin of the tooth blank is gradually squeezed downward, and the gear end face wall thickness is accumulated at the bottom of the tooth. Step S3 also includes a tooth forming mold, and the tooth blank is placed in the tooth forming mold. Through upsetting by the hydraulic press, a standard tooth shape is formed around the tooth blank.

[0019] Preferably, in step S1, it also includes an aluminum drawing die; the aluminum alloy billet is heated at high temperature to soften it, and is made into an aluminum alloy profile with a hole in the middle and teeth on the outer peripheral surface through the extruder and the aluminum drawing die; in step S2, the mass or volume required for the product is calculated by modeling simulation software, and the aluminum alloy profile is cut to form a plurality of toothed billets; in step S3, the press is an oil hydraulic press, and the punch of the oil hydraulic press is slightly larger than the inner hole of the toothed billet. During upsetting, the hole wall margin of the toothed billet is gradually squeezed downward, and the gear end face wall thickness is accumulated at the bottom of the tooth; step S3 also includes a toothed die, the toothed billet is placed in the toothed die, and is upset by the oil hydraulic press to form a standard tooth shape around the toothed billet; and step S5 is also included, feedback adjustment: the relevant parameters of the mold and the toothed billet are adjusted according to the deviation of the toothed structure of the aluminum alloy synchronous pulley in S4.

[0020] A forming system for an aluminum alloy synchronous pulley includes: an extrusion forming system: used to heat an aluminum alloy billet at high temperature to soften it, and extrude it into an aluminum alloy profile with an inner hole in the middle and teeth on the outer peripheral surface; wherein the tooth surface structure of the aluminum alloy profile with teeth on the outer peripheral surface is smaller than the standard tooth structure.

[0021] Modeling and slitting system: used to calculate the mass or volume required for the product and to slit the aluminum alloy profile into multiple toothed blanks.

[0022] Upsetting forming system: used to extrude the tooth blank through a press, and finally form a pulley die with a thick wall at the bottom end of the tooth blank and a standard tooth shape at the periphery.

[0023] Machining system: used for auxiliary machining such as smoothing, deburring, and chamfering of the pulley mold to form an aluminum alloy synchronous pulley.

[0024] Preferably, the extrusion molding system includes a high-temperature aluminum extruder and an aluminum drawing die. The high-temperature aluminum extruder is connected to the aluminum drawing die and is used to heat the aluminum alloy billet at high temperature to soften it, and extrude it into an aluminum alloy profile with an inner hole in the middle and teeth on the outer peripheral surface.

[0025] Preferably, the modeling and slitting system includes a modeling and simulation system and a cutting system; the modeling and simulation system is used to calculate the mass or volume required for the product; and the cutting system is used to slit the aluminum alloy profile to form a plurality of toothed blanks.

[0026] Preferably, the upsetting forming system includes a hydraulic press and a tooth forming die; the punch size of the hydraulic press is equal to the inner diameter of the aluminum alloy synchronous pulley and larger than the inner hole of the tooth forming blank; the tooth surface structure size of the tooth forming die is equal to the standard tooth forming structure size.

[0027] Preferably, an ejection system is provided at the bottom of the tooth forming mold; the ejection system includes a movable bottom plate and a hydraulic cylinder at the bottom of the tooth forming mold; the hydraulic cylinder is connected to the bottom of the bottom plate, providing support force to the bottom plate while driving the bottom plate to move upward.

[0028] Compared with the prior art, the advantages and positive effects of the present invention are:

[0029] 1. The application of this lightweight aluminum pulley cold heading process greatly improves raw material utilization. Raw material utilization has increased by 45%, processing costs have decreased by 28%, and based on an annual output of 800,000 pieces, profits can increase by more than 5 million yuan, with good social benefits.

[0030] Second, it eliminates the limitations of traditional, complex machining processes, such as low efficiency, high processing costs, and lengthy process flows. When bar profiles are outsourced, only a single hydraulic press press and simple surface treatment are required to complete the product. The ramming process achieves standard tooth profile dimensions, ensuring stable dimensional control suitable for mass production and adapting to automated production lines. This ensures product quality and reduces manufacturing costs.

[0031] 3. The tooth surface structure is formed by extrusion, and the surface quality is smoother, avoiding the impact of tool marks produced during layered milling on the surface quality. At the same time, the extrusion process will cause the material to undergo work hardening, thereby improving the strength and hardness of the material.

[0032] Cold heading is a precision pressure forming process. After metal extrusion, fibers are continuously and completely formed, resulting in refined grains and improved mechanical properties. The extrusion process flattens the metal surface of the finished product. The resulting surface roughness is low (i.e., smooth), typically reaching Ra0.8. Improving the accuracy and finish of synchronous pulley teeth significantly extends the service life of the belt, reduces costs, and improves overall equipment performance.

[0033] Fifth, manufacturing costs are low: a single set of cold heading dies can complete batch production. Different models and specifications of synchronous pulleys can be manufactured with only the cost of the die. Cold precision pressing is a process with little or no cutting. The finished workpiece is very close to the final product, with minimal machining allowance and high material utilization, saving raw materials and reducing production costs. For batch production, this not only saves labor time but also reduces product costs, achieving a 30% improvement in technical and economic benefits compared to conventional machining processes.

[0034] 6. The purpose of pre-forming by extrusion is to stabilize the subsequent pulley tooth profile size. This is because the synchronous pulley tooth profile is a special-shaped part, and extrusion molding can pre-distribute the material first. This can reduce the secondary cold heading pressure. Secondly, the material flows smoothly during cold heading, and it can also reduce material fission, ensuring that the secondary molding tooth profile is full and the size is stable. Thirdly, it is easy to remove the material without affecting the deformation of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is an overall schematic diagram of the extrusion molding system of the present invention.

[0036] Figure 2 It is a schematic diagram of the extrusion molding system of the present invention.

[0037] Figure 3 It is a schematic diagram of the aluminum alloy profile and the tooth blank of the present invention.

[0038] Figure 4 It is a three-dimensional schematic diagram of the upsetting forming system of the present invention.

[0039] Figure 5 It is a schematic diagram of the upsetting forming system of the present invention.

[0040] Figure 6 It is a schematic diagram of the punch operation of the oil press of the present invention.

[0041] Figure 7 It is a schematic diagram of an aluminum alloy synchronous pulley of the present invention. DETAILED DESCRIPTION

[0042] In order to make the purpose and technical solution of the present invention clearer, the present invention will be further described below with reference to the accompanying drawings and embodiments:

[0043] A forming process for an aluminum alloy synchronous pulley comprises the following steps:

[0044] S1, high-temperature aluminum drawing: heating the aluminum alloy billet at high temperature to soften it, and forming it into an aluminum alloy profile with an inner hole in the middle and teeth on the outer peripheral surface through an extruder; wherein the tooth surface structure of the aluminum alloy profile with teeth on the outer peripheral surface is smaller than the standard tooth structure.

[0045] In step S1, a high-temperature aluminum extruder and an aluminum drawing die can be used to achieve: the aluminum alloy billet is heated at high temperature to soften it, and an aluminum alloy profile 3 with a hole in the middle and teeth on the outer peripheral surface is made through an extruder (high-temperature aluminum extruder 1) and an aluminum drawing die 2. The high-temperature heating, i.e., extrusion, can be directly performed using a high-temperature aluminum extruder (such as Figure 1 、 Figure 2 shown).

[0046] S2, bar material measurement and cutting: the mass or volume required for the product is measured, and the aluminum alloy profile 3 is cut into multiple toothed blanks 4.

[0047] In step S2, the mass or volume required for the product can be calculated by modeling simulation software, and a cutting machine (not shown in the figure) is used to cut the aluminum alloy profile into a plurality of tooth blanks 4 (such as Figure 3 shown);

[0048] S3, upsetting forming: the tooth blank is extruded by a press, and finally the bottom end of the tooth blank is formed into a pulley mold with a thick wall and a standard tooth shape at the periphery.

[0049] In step S3, the press is a hydraulic press, and the punch 5 of the hydraulic press is slightly larger than the inner hole of the gear blank. During the upsetting, the hole wall margin of the gear blank is gradually squeezed downward, and the gear end face wall thickness is accumulated at the bottom of the gear. In step S3, a gear die 6 is also included. The gear blank is placed in the gear die, and the gear blank is upset by the hydraulic press to form a standard tooth shape ( Figures 4 to 6 shown).

[0050] S4, machining: A machine tool (not shown in the figure) is used to perform auxiliary machining such as smoothing, deburring, and chamfering on the pulley mold to form an aluminum alloy synchronous pulley. Machine tool processing is a traditional process and will not be described in detail in this invention.

[0051] The method further includes step S5, feedback adjustment: adjusting parameters related to the mold and the gear blank according to the deviation of the tooth structure of the aluminum alloy synchronous pulley in S4.

[0052] The inventor conducted experimental research and found that adjustments can be made to key locations based on experimental tests:

[0053] 1. Synchronous pulleys generally perform cyclic motion. At a certain fixed moment, multiple teeth often contact the synchronous belt and are subjected to stress at the same time. However, the stress conditions of each tooth are basically the same. The stress of multiple teeth can be regarded as the superposition of the stress effects of a single tooth. Therefore, only performing stress analysis on a single tooth can actually achieve the expected strain trend analysis purpose.

[0054] 2. According to stress analysis simulation, the stress-strain trend is most obvious in the pulley center hole and the gear tooth surface, and the maximum value appears on the cylindrical surface inside the small hole, so this is the location that needs to be monitored most.

[0055] 3. As for the gear teeth, since the synchronous belts have a unified standard, if you need to increase the gear tooth strength, you can choose a larger series of synchronous belts. At the same time, the gear tooth size will also increase accordingly, which requires adjustment from the initial die size.

[0056] 4. Add a hub at the axle hole and lengthen and thicken the axle hole, but generally leave a certain strength margin, because lightweighting improves transmission efficiency.

[0057] like Figures 1 to 7 As shown, the present invention also provides a forming system for an aluminum alloy synchronous pulley, comprising:

[0058] Extrusion molding system: used for heating aluminum alloy billets at high temperature to soften them, and extruding them into aluminum alloy profiles with an inner hole in the middle and teeth on the outer peripheral surface; wherein the tooth surface structure of the aluminum alloy profile with teeth on the outer peripheral surface is smaller than the standard tooth structure; the extrusion molding system includes a high-temperature aluminum extruder 1 and an aluminum drawing die 2, wherein the high-temperature aluminum extruder 1 is connected to the aluminum drawing die 2, and is used for heating aluminum alloy billets at high temperature to soften them, and extruding them into aluminum alloy profiles 3 with an inner hole in the middle and teeth on the outer peripheral surface.

[0059] Modeling and slitting system: used to measure the mass or volume required for the product, and to cut the aluminum alloy profile into a plurality of the toothed blanks 4; the modeling and slitting system includes a modeling simulation system (not shown in the figure) and a cutting system; the modeling simulation system is used to measure the mass or volume required for the product; the cutting system is used to cut the aluminum alloy profile into a plurality of the toothed blanks. In this embodiment, the cutting system adopts a cutting machine (not shown in the figure).

[0060] Upsetting forming system: used to extrude the gear blank through a press, and finally form a pulley die with a thick wall at the bottom end of the gear blank and a standard tooth shape around the periphery; the press is an oil press, and the punch 5 of the oil press is slightly larger than the inner hole of the gear blank 4. The tooth surface structure size of the gear die is equal to the standard tooth structure size. During upsetting, the hole wall margin of the gear blank is gradually squeezed downward, and the gear end face wall thickness is accumulated at the bottom of the gear; in the step S3, a gear die 6 is also included, the gear blank 4 is placed in the gear die, and the gear blank is upset by the oil press, and the standard tooth shape ( Figures 4 to 6 shown).

[0061] Machining system: used for performing auxiliary machining such as smoothing, deburring, and chamfering on the pulley mold to form an aluminum alloy synchronous pulley 7; this embodiment adopts a machine tool (not shown in the figure) to perform auxiliary machining such as smoothing, deburring, and chamfering on the pulley mold to form an aluminum alloy synchronous pulley.

[0062] Preferably, an ejection system is provided at the bottom of the tooth forming mold; the ejection system includes a movable bottom plate 61 and a hydraulic cylinder (not shown in the figure) at the bottom of the tooth forming mold; the hydraulic cylinder is connected to the bottom of the bottom plate, and while providing support force to the movable bottom plate, it can drive the bottom plate to move upward to eject the tooth forming blank after upsetting.

[0063] In the description of the invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," "the other end," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] In the description of the invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "provided with," "connected," etc., should be understood broadly. For example, "connected" may refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0065] The components used in the present invention are all universal standard parts or components known to those skilled in the art, such as its high-temperature aluminum extruder, aluminum drawing die, hydraulic press, etc., whose structures and principles can be known to those skilled in the art through technical manuals or conventional experimental methods.

[0066] The above description is merely a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any minor modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of protection of the present invention.

Claims

1. A forming process for an aluminum alloy synchronous pulley, characterized in that: The following steps are involved: S1, high temperature aluminum drawing: the aluminum alloy billet is heated at high temperature to soften it, and an aluminum alloy profile having an inner hole in the middle and teeth on the outer peripheral surface is formed by an extruder; wherein the tooth surface structure of the aluminum alloy profile having teeth on the outer peripheral surface is smaller than the standard tooth structure; S2, bar material measurement and cutting: Calculate the mass or volume required for the product, and cut the aluminum alloy profile into multiple toothed blanks; S3, upsetting forming: the tooth blank is extruded by a press, and finally the bottom end of the tooth blank is formed into a pulley mold with a thick wall and a standard tooth shape at the periphery; S4, machining: perform auxiliary machining such as smoothing, edge removal, and chamfering on the pulley mold to form an aluminum alloy synchronous pulley.

2. The forming process of an aluminum alloy synchronous pulley according to claim 1, characterized in that: In step S1, it also includes an aluminum drawing die; the aluminum alloy billet is heated at high temperature to soften it, and is made into an aluminum alloy profile with a hole in the middle and teeth on the outer peripheral surface through the extruder and the aluminum drawing die.

3. The forming process of an aluminum alloy synchronous pulley according to claim 1 is characterized in that: In step S2, the mass or volume required for the product is calculated by modeling and simulation software, and the bar is cut into a plurality of tooth blanks.

4. The forming process of an aluminum alloy synchronous pulley according to claim 1, characterized in that: In step S3, the press is a hydraulic press, the punch of which is slightly larger than the inner hole of the gear blank, and the hole wall margin of the gear blank is gradually squeezed downward during upsetting, accumulating to form the gear end face wall thickness at the bottom of the gear; The step S3 also includes a tooth forming die, in which the tooth forming blank is placed and pressed by a hydraulic press to form a standard tooth shape around the tooth forming blank.

5. The forming process of an aluminum alloy synchronous pulley according to claim 1, characterized in that: In step S1, it also includes an aluminum drawing die; the aluminum alloy billet is heated at high temperature to soften it, and is made into an aluminum alloy profile with a hole in the middle and teeth on the outer peripheral surface through the extruder and the aluminum drawing die; In step S2, the mass or volume required for the product is calculated by modeling and simulation software, and the aluminum alloy profile is cut into a plurality of tooth blanks; In step S3, the press is a hydraulic press, the punch of which is slightly larger than the inner hole of the gear blank, and the hole wall margin of the gear blank is gradually squeezed downward during upsetting, accumulating to form the gear end face wall thickness at the bottom of the gear; The step S3 also includes a gear forming die, wherein the gear forming blank is placed in the gear forming die and is pressed by a hydraulic press to form a standard tooth shape around the gear forming blank; The method further includes step S5, feedback adjustment: adjusting the parameters related to the mold and the gear blank according to the deviation of the tooth structure of the aluminum alloy synchronous pulley in S4.

6. A forming system for an aluminum alloy synchronous pulley, characterized in that: include: Extrusion molding system: used to heat the aluminum alloy billet at high temperature to soften it, and extrude it into an aluminum alloy profile with an inner hole in the middle and teeth on the outer peripheral surface; wherein the tooth surface structure of the aluminum alloy profile with teeth on the outer peripheral surface is smaller than the standard tooth structure; Modeling and slitting system: used to calculate the mass or volume required for the product, and to slitting the aluminum alloy profiles into multiple toothed blanks; Upsetting forming system: used to extrude the tooth blank through a press, and finally form a pulley die with a thick wall at the bottom end of the tooth blank and a standard tooth shape at the periphery; Machining system: used for auxiliary machining such as smoothing, edge removal, chamfering, etc. of the pulley mold to form an aluminum alloy synchronous pulley.

7. The forming system of an aluminum alloy synchronous pulley according to claim 6, characterized in that: The extrusion molding system includes a high-temperature aluminum extruder and an aluminum drawing die. The high-temperature aluminum extruder is connected to the aluminum drawing die and is used to heat the aluminum alloy billet at high temperature to soften it, and extrude it into an aluminum alloy profile with an inner hole in the middle and teeth on the outer peripheral surface.

8. The forming system of an aluminum alloy synchronous pulley according to claim 6, characterized in that: The modeling and cutting system includes a modeling simulation system and a cutting system; The modeling and simulation system is used to calculate the mass or volume required for the product; The cutting system is used for cutting the aluminum alloy profile into a plurality of toothed blanks.

9. The forming system of an aluminum alloy synchronous pulley according to claim 6, characterized in that: The upsetting forming system includes an oil press and a tooth forming die; The punch size of the hydraulic press is equal to the inner diameter of the aluminum alloy synchronous belt pulley and larger than the inner hole of the toothed blank; The tooth surface structural dimensions of the tooth forming mold are equal to the standard tooth forming structural dimensions.

10. The forming system of an aluminum alloy synchronous pulley according to claim 6, characterized in that: The bottom of the tooth forming mold is provided with an ejection system; The ejection system comprises a movable bottom plate and a hydraulic cylinder at the bottom of the tooth forming mold; the hydraulic cylinder is connected below the movable bottom plate, and can drive the bottom plate to move upward while providing support force to the bottom plate.

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