Low-temperature high-efficiency tread extrusion and off-machine compounding device

Abstract

The present application relates to the technical field of tire manufacturing equipment, and specifically relates to a low-temperature and high-efficiency tread extrusion and off-machine compounding device, which comprises a machine body, single-roll extruders and a compounding mechanism, the single-roll extruders are provided with two, each single-roll extruder comprises a screw extruder for conveying rubber material, and the two screw extruders are parallel to each other; the compounding mechanism is arranged between the two single-roll extruders and is used for compounding the rubber materials extruded by the two single-roll extruders. The present application realizes the extrusion of two different formula products by two independent single-roll extruders, and then realizes the lamination off the machine, so as to have the characteristics of low extrusion product temperature and low extrusion pressure, effectively solves the phenomenon of premature vulcanization caused by high extrusion temperature of the rubber material, achieves the reduction of the extrusion temperature of the rubber material, the guarantee of the compounding precision and the reduction of the comprehensive operation energy consumption of the equipment, improves the extrusion quality of the compounded tread from the source, and provides support for the quality improvement, cost reduction and efficiency improvement of the tire enterprise.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tire manufacturing equipment, in particular to a low-temperature and high-efficiency tread extrusion and off-machine compounding device. BACKGROUND

[0002] In the field of tire tread manufacturing, the traditional in-machine compounding extrusion technology has long dominated. This technology uses a single compounding extrusion device, with multiple extruders arranged above and below working together to make the different formula rubbers realize high-temperature and high-pressure compounding inside the co-extrusion head. The device is usually arranged in a V shape: the upper machine extrudes the crown rubber, and the lower machine processes the base rubber or the side rubber. The two rubbers are combined through a precise flow channel and are forced to press and form at the die plate.

[0003] However, this process has significant defects:

[0004] First, there is a risk of high-temperature scorching. The reason is that the rubber needs to be transported through a 1.5-2 meter winding path in the flow channel inside the head, and is compounded in a high-pressure environment of 18-45 MPa. During this process, the continuous friction between the rubber and the flow channel wall causes the temperature to rise sharply. Especially for high-white carbon black content formulas (the proportion in the tread rubber is usually more than 30%), poor dispersibility is more likely to cause local overheating, with a temperature peak of more than 120°C, approaching the scorching critical point of natural rubber (NR) and styrene-butadiene rubber (SBR). High temperature causes the rubber to undergo early vulcanization, generating micro-scorch particles, reducing the tensile strength of the rubber, and ultimately damaging the durability of the tire.

[0005] Second, the energy consumption and cost are high. To control the temperature of the rubber, the traditional solution requires multiple devices such as plastic extruders, coarse / precision refining mills, and hot feed extruders, with a total motor power of about 1300 kW, resulting in huge energy consumption. At the same time, the compounding head requires a hydraulic locking structure, which has high processing complexity and a single device investment cost of 15 million yuan.

[0006] In addition, the traditional in-machine compounding has poor adaptability to the difference in rubber shrinkage, which easily leads to wrinkles and delamination of the compounded tread; and lacks a real-time and accurate size control mechanism for the extruded rubber, affecting the compounding centering accuracy.

[0007] Therefore, we propose a low-temperature and high-efficiency tread extrusion and off-machine compounding device to solve the above problems. SUMMARY

[0008] Technical problems to be solved

[0009] In view of the above shortcomings of the prior art, the present application provides a low-temperature and high-efficiency tread extrusion and off-machine compounding device, which can solve the problem of high cost of the tire tread compounding device in the prior art and the problem of defects in the tread processing caused by high temperature.

[0010] Technical scheme

[0011] To achieve the above object, the present application is realized by the following technical solutions:

[0012] The present application provides a low-temperature high-efficiency tread extrusion and off-machine compounding device, comprising a machine body, a single-roll extruder and a compounding mechanism, the single-roll extruder is provided with two, each single-roll extruder comprises a screw extruder for conveying rubber material, and the two screw extruders are parallel in axis; the compounding mechanism is arranged between the two single-roll extruders and is used for compounding the rubber materials extruded by the two single-roll extruders; wherein the end of each screw extruder is provided with a roller for extruding rubber material into a shape, and a cutting mechanism for cutting rubber material is arranged on the side of the roller away from the screw extruder; after the rubber material is cut by the cutting mechanism, it enters the compounding mechanism through the conveying roller arranged on the back side of the two cutting mechanisms.

[0013] Further, the single-roll extruder further comprises a feeder, an inlet hopper is arranged above the starting section of the screw extruder, and the end of the feeder is located directly above the inlet hopper.

[0014] Further, the screw extruder is internally provided with a screw, a plurality of pins are detachably inserted into the outer side end of the screw extruder, one end of each pin is inserted into the interior of the screw extruder along the radial direction of the screw extruder, and a notch is formed on the screw corresponding to the position of the pin.

[0015] Further, the plurality of pins are divided into a plurality of groups, and the pins in each group are arranged on the outer side end surface of the screw extruder in a ring shape.

[0016] Further, the cutting mechanism comprises a lower roller parallel to the roller, two cutters are arranged above the lower roller, and the distance and height between the two cutters are adjustable.

[0017] Further, two visual detection cameras for collecting image information of the rubber material on the roller are arranged directly above the roller, and the visual detection cameras are in communication connection with the driving mechanism for controlling the movement of the cutters in the two single-roll extruders.

[0018] Further, two observation holes are arranged on the single-roll extruder, and each observation hole is located between the roller and the visual detection camera.

[0019] Further, the compounding mechanism comprises two auxiliary rollers and a compounding roller, the two auxiliary rollers are perpendicular to the conveying direction of the conveying roller in axis, and the compounding roller is composed of a rotatable shaft roller and a cylindrical compression roller sleeved on the shaft roller.

[0020] Further, the compression roller is composed of a plurality of disc-shaped roller pieces sleeved on a shaft roller, an axis length of the roller pieces is less than an axis length of the shaft roller, and a position of the roller pieces on the shaft roller is adjustable.

[0021] Further, a middle part of the roller piece is provided with a circular hole, a diameter of the circular hole is greater than a diameter of the compression roller.

[0022] Advantages

[0023] Compared with the prior art, the technical scheme provided by the application has the following advantages:

[0024] The application realizes extrusion of two different formula products by two independent single-roller extruders, and then realizes lamination outside the machine, so that the extruded product has the characteristics of low temperature and low pressure, effectively solves the phenomenon of premature vulcanization caused by high extrusion temperature of the rubber material, reduces the extrusion temperature of the rubber material, ensures the composite precision, reduces the comprehensive operation energy consumption of the equipment, improves the extrusion quality of the composite tread from the source, and provides support for the quality improvement, cost reduction and efficiency improvement of the tire enterprise; meanwhile, the rubber material can use recyclable plastic material, which is more environmentally friendly and diversified.

[0025] And in the traditional in-machine composite extrusion scheme, a composite head is used, the head needs to use hydraulic locking, the structure is complex, and the processing cost is high, while in the present scheme, although there are two single-roller extruders, the single-roller structure is used, the manufacturing and processing are relatively simple, the investment cost of the same configuration equipment is lower than that of the composite equipment, and the enterprise investment cost is further reduced. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical schemes in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0027] Figure 1 It is a schematic view of the overall structure of the composite device in the embodiment of the application;

[0028] Figure 2 It is a schematic view of the overall structure of the composite device in the embodiment of the application;

[0029] Figure 3 It is a schematic view of the single-roller extruder in the embodiment of the application;

[0030] Figure 4 It is a schematic view of the structure at A in the embodiment of the application; Figure 3

[0031] Figure 5 ​This is a schematic diagram of the composite mechanism in an embodiment of the present invention;

[0032] Figure 6 This is a top view of the composite mechanism in an embodiment of the present invention;

[0033] Figure 7 This is a side view cross-sectional structural diagram of the composite mechanism in an embodiment of the present invention;

[0034] Figure 8 This is a partial cross-sectional view of the screw extruder in an embodiment of the present invention.

[0035] The labels in the diagram represent: 1. Machine body; 2. Single-roll extruder; 20. Roller; 201. Conveyor roller; 21. Screw extruder; 211. Feed hopper; 212. Pin; 22. Cutting mechanism; 221. Lower roller; 222. Cutter; 223. Vision inspection camera; 224. Observation hole; 3. Compounding mechanism; 31. Auxiliary roller; 32. Compound roller; 321. Shaft roller; 322. Pressure roller; 323. Roller blade; 324. Circular hole. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0037] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0038] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0039] In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used to distinguish in description, and have no special meaning.

[0040] The present application will be further described below in conjunction with the embodiments.

[0041] Embodiment:

[0042] Please refer to the accompanying Figures 1-8 The present application provides a low-temperature and high-efficiency tire tread extrusion and off-machine compounding device, which comprises a machine body 1, a single-roll extruder 2 and a compounding mechanism 3. The single-roll extruder 2 in the present application is provided with two single-roll extruders 2 distributed in an upper and lower manner. Each single-roll extruder 2 comprises a screw extruder 21 for conveying rubber material. The two screw extruders 21 have parallel axes.

[0043] Each single-roll extruder 2 comprises a feeder 23 composed of a conveying belt and a conveying roller located at the front end of the conveying belt. An inlet hopper 211 is arranged above the starting section of the screw extruder 21. The end of the feeder 23 is located directly above the inlet hopper 211. The rubber material conveyed by the feeder 23 will fall directly into the inlet hopper 211.

[0044] The screw extruder 21 is internally provided with a screw which is driven to rotate by a driving mechanism arranged on one side of the machine body 1. It should be noted that the rubber material needs to be sheared when passing through the screw extruder 21. The screw used in the present application is a double-head deep groove screw.

[0045] The rubber material first falls accurately into the inlet hopper 211 above the starting section of the screw extruder 21 through the feeder 23, and is conveyed to the end under the rotation of the screw extruder 21.

[0046] Specifically, the outer end of the screw extruder 21 has multiple holes, and multiple pins 212 are detachably inserted into these holes. The operator selects the number of pins to insert according to the rubber compound formula. The ends of the pins extend radially into the rubber compound flow channel. A rectangular notch is provided at the corresponding position on the screw. When the rubber compound flows through the notch area, the pins 212 shear and tear the rubber compound. One end of each pin 212 is inserted radially into the screw extruder 21. When the rubber compound inside the screw extruder 21 is conveyed forward by the screw, it comes into contact with the pins 212, and the pins 212 shear the conveyed rubber compound. The notch on the screw at the position corresponding to the pins 212 prevents the pins 212 from interfering with the screw.

[0047] It is worth noting that the multiple pins 212 are divided into several groups, and the groups of pins 212 are arranged at intervals on the outer end face of the screw extruder 21. Each group of pins 212 is distributed in a ring on the outer end face of the screw extruder 21, so that the rubber material can be sheared evenly and sheared multiple times during the stroke.

[0048] It should be noted that traditional in-machine compound extrusion schemes have a high content of silica in the tread rubber, and silica has poor dispersion in rubber. During extrusion, the rubber compound in the head section heats up significantly. To ensure a lower temperature during extrusion, a low-heat-generating short-screw hot-feed extruder is conventionally used as the host extruder to extrude the rubber compound (because directly using a cold-feed extruder can easily cause overheating of the extruded product). The rubber compound required for the hot-feed extruder needs to be plasticized, roughened, and refined before it can be supplied to the hot-feed extruder. In this process, the rubber compound temperature changes from heating up to cooling down to cooling down again and then heating up again in order to control the overall rubber temperature. To achieve continuous production, this requires a plasticizing extruder, a roughing open mill, a refining open mill, and a hot-feed extruder of appropriate size and specifications. The combined power of the motors for these machines is approximately 1300 kW, resulting in high energy consumption during equipment operation.

[0049] In this application, two single-roller extruders are used, eliminating the need for them to operate in a single unit. Traditional in-machine compound extrusion solutions require a compound die head with hydraulic locking, resulting in a complex structure and high processing costs. The investment cost for the same equipment configuration is approximately RMB 15 million per unit. Although the newly designed external compound extrusion model has two machines, its single-machine structure simplifies manufacturing and processing. The investment cost for the same equipment configuration is only RMB 11 million per unit, saving users RMB 4 million in direct equipment investment costs per unit.

[0050] The product extruded by the single-roller barrel extruder has the characteristics of low extrusion product temperature and low extrusion pressure. Two independent single-roller extruders are used to replace the structure type of two extruders + in-machine composite head to realize the extrusion of two different formula products, and then the products are compounded outside the machine. The composite mechanism 3 is arranged between the two single-roller extruders 2, and is used to compound the rubber materials extruded by the two single-roller extruders 2. The end of each screw extruder 21 is provided with a roller 20 for extruding the rubber material into a shape. A cutting mechanism 22 for cutting the rubber material is arranged on the side of the roller 20 away from the screw extruder 21. The cutting mechanism 22 is installed on the outlet side of the roller 201 of each single-roller extruder 2. The cutting mechanism 22 includes a lower roller 221 and two groups of independently driven cutter assemblies.

[0051] In addition, since low-temperature and low-pressure extrusion is adopted, the phenomenon of premature vulcanization caused by high extrusion temperature is effectively solved, the extrusion temperature of the rubber material is reduced, the compounding accuracy is ensured, the comprehensive operating energy consumption of the equipment is reduced, the extrusion quality of the compound tread is improved from the source, and support is provided for the quality improvement, cost reduction and efficiency improvement of the tire enterprise.

[0052] Since a set of numerical control cutter device is arranged at each single-roller head part, the width of the extruded rubber material can be cut according to the formula requirement, so that the width size of each rubber block meets the requirement. In order to solve the accuracy of the adhesion of the two kinds of rubber materials and the uncontrollability of the size caused by the shrinkage of different rubber materials, the rubber material of the thick product is pre-shrunk, so that the two kinds of rubber materials do not produce wrinkles and delamination due to different shrinkage after being attached. During the centering and attaching process of the two kinds of rubber materials, the position of the rubber material is detected and controlled at any time by the two sets of CCD cameras, and the overall left and right movement of the cutter is controlled, so that the centering accuracy of the attachment of the two kinds of rubber materials is controlled within the process requirement.

[0053] The cutter 222 adopts a tungsten steel disc cutter blade, which can be lifted in the vertical direction by a servo motor and the horizontal spacing is also adjustable.

[0054] Two CCD visual detection cameras 223 are arranged directly above the roller 201. The collection direction of the cameras is directly above the central axis of the roller 201 to align the rubber material on the surface of the roller.

[0055] Notably, two observation holes 224 are arranged on the single-roller extruder 2, and each observation hole 224 is located between the roller 20 and the visual detection camera 223, so as to reduce the image taking range of the camera and improve the response speed.

[0056] The camera and the cutter servo system are connected through an industrial Ethernet, and the edge position data of the rubber material is analyzed in real time.

[0057] After the rubber material is cut by the cutting mechanism 22, the rubber material enters the composite mechanism 3 through the conveying roller 201 arranged on the rear side of the two cutting mechanisms 22.

[0058] When the base rubber material extruded by the upper extruder is formed into a strip shape by the roller, the visual camera 223 detects that the right edge of the rubber material deviates from the designed position due to shrinkage. The control system immediately drives the right cutter 222 to move left for compensation cutting, so that the width of the rubber material is accurately kept at the expected position.

[0059] The cut rubber block falls into the lower conveying roller 201, and the two conveying rollers run at the same speed to synchronously convey the two rubber materials to the compounding mechanism 3.

[0060] The compounding mechanism 3 includes two auxiliary rollers 31 and a compounding roller 32, the auxiliary rollers 31 are perpendicular to the conveying direction of the conveying roller 201, the compounding roller 32 is composed of a rotatable shaft roller 321 and a cylindrical compression roller 322 sleeved on the shaft roller 321, the compression roller 322 is composed of a plurality of disc-shaped roller pieces 323 sleeved on the shaft roller 321, the axis length of the roller pieces 323 is less than that of the shaft roller 321, and the position of the roller pieces 323 on the shaft roller 321 is adjustable, the middle part of the roller piece 321 is provided with a circular hole 324, and the diameter of the circular hole 324 is greater than that of the compression roller 32.

[0061] The compounding mechanism 3 is located at the middle position of the two single-roll extruders, and includes two auxiliary rollers 31 and a compounding roller 32.

[0062] The surface of the auxiliary roller 31 is coated with a silica gel layer to increase the friction coefficient and ensure smooth transition of the rubber material. The shaft roller 321 of the compounding roller is made of high-strength alloy steel, and its two ends are fixed through a hydraulic bearing seat. A plurality of 304 stainless steel roller pieces 323 are sleeved on the shaft roller, the circular hole 324 in the inner diameter of the roller piece 323 is 2 mm larger than the diameter of the shaft roller, so that the roller piece can move up and down along the shaft roller. The rubber material is compacted by the special gravity multi-piece compression roller, which not only ensures the bonding strength, but also prevents the extrusion deformation of the compression device on the rubber material.

[0063] The other side of the compounding mechanism 3 is provided with a discharge port to convey the tire tread formed by compounding to the next process.

[0064] When producing a 215 / 55R17 specification tread, the slope on the tread has fluctuations, so when the rubber material passes through, the roller piece 323 can move up and down according to the fluctuation of the height, which can ensure automatic production and also compact the shoulder part, ensuring high-strength bonding of the tread.

[0065] The above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements will not make the essence of the corresponding technical solutions deviate from the protection scope of the technical solutions of the embodiments of the present application.

Claims

1. A low-temperature, high-efficiency tread extrusion and external compounding device, comprising: Body (1); A single-roller extruder (2) is provided, and two single-roller extruders (2) are provided. Each single-roller extruder (2) includes a screw extruder (21) for conveying rubber material. The two screw extruders (21) are parallel in axis. A compounding mechanism (3) is provided between two single-roll extruders (2) and is used to compound the rubber material extruded by the two single-roll extruders (2); Each screw extruder (21) is equipped with a roller (20) for extruding rubber material at its end. A cutting mechanism (22) for cutting rubber material is provided on the side of the roller (20) away from the screw extruder (21). After the rubber material is cut by the cutting mechanism (22), it enters the compounding mechanism (3) through the conveying roller (201) provided behind the two cutting mechanisms (22). The screw extruder (21) has a screw inside, and multiple pins (212) are detachably inserted at the outer end of the screw extruder (21). One end of each pin (212) is inserted into the screw extruder (21) along the radial direction, and a notch is opened on the screw corresponding to the position of the pin (212). The cutting mechanism (22) includes a lower roller (221) parallel to the roller (20), and two cutters (222) are provided above the lower roller (221), and the distance and height between the two cutters (222) are adjustable; Two visual inspection cameras (223) are provided directly above the roller (20) for collecting image information of the rubber material on the roller (20). The visual inspection cameras (223) are communicatively connected to the drive mechanism in the two single-roll extruders (2) for controlling the movement of the cutter (222). The composite mechanism (3) includes two auxiliary rollers (31) with axes perpendicular to the conveying direction of the conveying roller table (201) and a composite roller (32). The composite roller (32) consists of a rotatable shaft roller (321) and a columnar pressure roller (322) sleeved on the shaft roller. The pressure roller (322) is composed of multiple disc-shaped rollers (323) sleeved on the shaft roller (321). The axial length of the roller (323) is less than the axial length of the shaft roller (321), and its position on the shaft roller (321) is adjustable. During the centering and bonding process of the two adhesives, the position of the adhesives is detected at any time by two vision inspection cameras (223) and the cutting blade (222) is moved left and right as a whole to ensure that the centering accuracy of the bonding of the two adhesives is controlled within the process requirements.

2. The low-temperature high-efficiency tread extrusion and external lamination device according to claim 1, characterized in that, The single-roll extruder (2) also includes a feeder (23), and a feed hopper (211) is provided above the starting section of the screw extruder (21), with the end of the feeder (23) located directly above the feed hopper (211).

3. The low-temperature high-efficiency tread extrusion and external lamination device according to claim 1, characterized in that, The multiple pins (212) are divided into several groups, and the several groups of pins (212) are arranged at intervals on the outer end face of the screw extruder (21). Each group of pins (212) is distributed in a ring on the outer end face of the screw extruder (21).

4. The low-temperature high-efficiency tread extrusion and external lamination device according to claim 1, characterized in that, The single-roll extruder (2) is provided with two observation holes (224), each observation hole (224) being located between the roller (20) and the vision inspection camera (223).

5. The low-temperature high-efficiency tread extrusion and external lamination device according to claim 4, characterized in that, A circular hole (324) is provided in the middle of the roller (321), and the diameter of the circular hole (324) is larger than the diameter of the pressure roller (32).

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