Low-temperature high-efficiency tread extrusion and external compounding device

Abstract

The invention relates to the technical field of tire manufacturing equipment, in particular to a low-temperature efficient tread extrusion and external compounding device which comprises a machine body, two single-roller extruders and a compounding mechanism, each single-roller extruder comprises a screw extruder for conveying rubber, and the axes of the two screw extruders are parallel; and the compounding mechanism is arranged between the two single-roller extruders and is used for compounding sizing materials extruded by the two single-roller extruders. Two products with different formulas are extruded through the two independent single-roller extruders and then are attached outside the single-roller extruders, so that the double-roller extruder has the characteristics of low temperature and low extrusion pressure of the extruded products, effectively solves the problem of advanced vulcanization of rubber materials caused by high extrusion temperature, and improves the product quality. The purposes of reducing the rubber extrusion temperature, ensuring the composite precision, reducing the comprehensive operation energy consumption of equipment and improving the extrusion quality of the composite tread from the source are achieved, and support is provided for quality improvement, cost reduction and efficiency improvement of tire enterprises.

Description

Technical Field

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

[0002] In tire tread manufacturing, traditional in-machine compounding extrusion technology has long dominated. This technology utilizes a single compounding extruder, with multiple extruders arranged in a vertical arrangement working in tandem to combine rubber compounds of varying formulations at high temperatures and high pressures within the extruder head. The equipment is typically arranged in a V-shape: the upper extruder extrudes the crown compound, while the lower extruder processes the base compound or sidewall compound. The two compounds flow through precise flow channels into the compounding die, where they are forcibly pressed together at the die plate.

[0003] However, this process has significant drawbacks:

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

[0005] Secondly, the energy consumption and cost are high. In order to control the temperature of the rubber compound, the traditional solution requires multiple equipment such as plasticizing extruder, coarse / fine mixing mill and hot feed extruder. The total motor power is about 1300kW, and the energy consumption is huge. At the same time, the composite die requires a hydraulic locking structure, and the processing is highly complex. The investment cost of a single device is as high as 15 million yuan.

[0006] In addition, traditional in-machine compounding has poor adaptability to differences in rubber shrinkage rates, which can easily lead to wrinkling and delamination of the composite tread; and there is a lack of a real-time and precise control mechanism for the size of the extruded rubber, which affects the accuracy of the composite centering.

[0007] To this end, we propose a low-temperature and high-efficiency tread extrusion and off-machine compounding device to solve the above-mentioned problems. Summary of the Invention

[0008] Technical problems solved

[0009] In response to the above-mentioned shortcomings of the prior art, the present invention provides a low-temperature, high-efficiency tread extrusion and off-machine compounding device, which can solve the problems of high cost of tire tread compounding equipment in the prior art and the tread processing defects easily caused by high temperature.

[0010] Technical Solution

[0011] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0012] The present invention 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, wherein two single-roll extruders are provided, each of which includes a screw extruder for conveying rubber material, and the axes of the two screw extruders are parallel; the compounding mechanism is arranged between the two single-roll extruders, and is used to compound the rubber material extruded by the two single-roll extruders; wherein, the end of each screw extruder is respectively provided with a roller for extruding the rubber material into shape, and a cutting mechanism for cutting the rubber material is provided on the side of the roller away from the screw extruder, and after the rubber material is cut by the cutting mechanism, it enters the compounding mechanism via a conveying roller arranged on the rear sides of the two cutting mechanisms.

[0013] Furthermore, the single-roll extruder also includes a feeder, and a feeding funnel is provided above the starting section of the screw extruder, and the end of the feeder is located directly above the feeding funnel.

[0014] Furthermore, a screw is provided inside the screw extruder, and a plurality of pins are detachably inserted at the outer end of the screw extruder. One end of each pin is inserted into the screw extruder along the radial direction of the screw extruder, and a notch is provided on the screw at the position corresponding to the pin.

[0015] Furthermore, the plurality of pins are divided into several groups, and the several groups of pins are arranged at intervals on the outer end surface of the screw extruder, and each group of pins is distributed in a ring shape on the outer end surface of the screw extruder.

[0016] Furthermore, the cutting mechanism includes a lower roller parallel to the roller, and two cutters are provided above the lower roller, and the distance and height between the two cutters are adjustable.

[0017] Furthermore, two visual inspection cameras for collecting image information of the rubber material on the roller are provided directly above the roller, and the visual inspection cameras are communicatively connected with the driving mechanisms for controlling the movement of the cutters in the two single-roller extruders.

[0018] Furthermore, the single-roll extruder is provided with two observation holes, each of which is located between the roller and the visual inspection camera.

[0019] Furthermore, the composite mechanism includes two auxiliary rollers whose axes are perpendicular to the conveying direction of the conveying roller and a composite roller. The composite roller is composed of a rotatable shaft roller and a columnar pressure roller sleeved on the shaft roller.

[0020] Furthermore, the pressure roller is composed of a plurality of disc-shaped roller sheets sleeved on the shaft roller, the axis length of the roller sheet is smaller than the axis length of the shaft roller and the position of the roller sheet on the shaft roller is adjustable.

[0021] Furthermore, a circular hole is provided in the middle of the roller sheet, and the diameter of the circular hole is larger than the diameter of the pressure roller.

[0022] Beneficial effects

[0023] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0024] The present invention realizes the extrusion of two products with different formulas through two independent single-roller extruders, and then bonds them together outside the machine, so that the extruded products have the characteristics of low temperature and low extrusion pressure, effectively solving the premature vulcanization phenomenon of rubber due to high extrusion temperature, achieving the goals of lowering rubber extrusion temperature, ensuring composite accuracy, and reducing the overall operating energy consumption of equipment, thereby improving the extrusion quality of the composite tread from the source, and providing support for tire companies to improve quality, reduce costs and increase efficiency; at the same time, the rubber can be made of recyclable plastic material, which is more environmentally friendly and diversified.

[0025] In addition, the traditional in-machine composite extrusion solution uses a composite die head, which requires hydraulic locking, has a complex structure and high processing cost. Although this solution has two single-roller extruders, it uses a single-roller structure, so the manufacturing and processing are relatively simple. The investment cost of the same equipment is lower than that of the composite equipment, further reducing the company's investment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0027] Figure 1 Schematic diagram of the overall structure of the composite device in an embodiment of the present invention;

[0028] Figure 2 It is a front view schematic diagram of the overall structure of the composite device in an embodiment of the present invention;

[0029] Figure 3 Schematic diagram of a single-roller extrusion mechanism in an embodiment of the present invention;

[0030] Figure 4 In the embodiment of the present invention Figure 3 Schematic diagram of the structure at A in the middle;

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

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

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

[0034] Figure 8 It is a schematic diagram of the partial cross-sectional structure of the screw extruder in an embodiment of the present invention.

[0035] The numbers in the figure represent: 1. Machine body; 2. Single-roller extruder; 20. Roller; 201. Conveyor roller; 21. Screw extruder; 211. Feed hopper; 212. Pin; 22. Cutting mechanism; 221. Lower roller; 222. Cutter; 223. Visual inspection camera; 224. Observation hole; 3. Composite mechanism; 31. Auxiliary roller; 32. Composite roller; 321. Shaft roller; 322. Pressure roller; 323. Roller; 324. Round hole. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0037] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0038] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0039] In the description of this embodiment, the terms "upper," "lower," "left," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0040] The present invention will be further described below with reference to the embodiments.

[0041] Example:

[0042] Please refer to the attached Figure 1-8 This proposal proposes a low-temperature, high-efficiency tread extrusion and off-machine composite device. The tread extrusion and off-machine composite device of the present invention includes a machine body 1, a single-roll extruder 2 and a composite mechanism 3. In this case, there are two single-roll extruders 2 distributed up and down. Each single-roll extruder 2 includes a screw extruder 21 for conveying rubber material, and the axes of the two screw extruders 21 are parallel.

[0043] Each single-roll extruder 2 includes a row of feeders 23, which are composed of a conveyor belt and a conveyor roller located at the front end of the conveyor belt. A feeding funnel 211 is provided above the starting section of the screw extruder 21. The end of the feeder 23 is located directly above the feeding funnel 211, and the rubber material conveyed by the feeder 23 will fall directly above the feeding funnel 211.

[0044] A screw is provided inside the screw extruder 21, and the screw is driven to rotate by a driving mechanism arranged on one side of the body 1. It should be noted that the rubber material needs to be sheared when passing through the screw extruder 21. A double-headed deep-groove screw is used in this case.

[0045] The rubber material firstly falls precisely into the feeding hopper 211 above the starting section of the screw extruder 21 through the feeder 23 , and is then transported to the end under the rotation of the screw extruder 21 .

[0046] Specifically, the outer end of the screw extruder 21 is provided with a plurality of holes, and a plurality of pins 212 are detachably inserted into the holes provided at the outer end of the screw extruder 21. The operator selects the number of pins to be inserted according to the rubber compound formula, and the ends of the pins radially extend into the rubber compound flow channel. A rectangular notch is provided at the corresponding position of 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 into the interior of the screw extruder 21 along the radial direction of the screw extruder 21. When the rubber compound inside the screw extruder 21 is transported forward by the screw, the rubber compound will come into contact with the pins 212, and the pins 212 will shear the transported rubber compound. A notch is provided on the screw at the position corresponding to the pins 212 to prevent 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 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 shape on the outer end face of the screw extruder 21, so that the rubber material can be sheared evenly and the rubber material can be sheared multiple times during the stroke.

[0048] It should be noted that the traditional in-machine composite extrusion solution has a high content of white carbon ink in the tread rubber, and the dispersion of white carbon ink in rubber is relatively poor. The temperature of the rubber material at the head of the extruder is high. In order to make the rubber material have a lower temperature when extruding, a low-heat-rise short-screw hot feed extruder is conventionally used as the host machine to extrude the rubber material (because the extruded product is prone to overheating when a cold feed extruder is directly used). The rubber material required by the hot feed extruder needs to be plasticized, roughed and refined in advance before it can be supplied to the hot feed extruder. In this process, it is equivalent to controlling the overall rubber temperature. The temperature change process of the rubber material is heating-cooling-cooling-reheating-heating. In order to achieve continuous production, it is necessary to match the corresponding specifications and sizes of plasticizing extruders, roughing mills, refining mills and hot feed extruders. The total power of the relevant motors of these units is about 1300kw, and the energy consumption of the equipment operation is very large.

[0049] However, two single-roll extruders 2 are used in this application, and there is no need to operate them in one device. The traditional in-machine composite extrusion solution uses a composite head, which requires hydraulic locking, has a complex structure, and has high processing costs. The investment cost of the same equipment is about 15 million yuan per set. Although the newly designed off-machine composite model has two machines, it adopts a single-machine structure, so the manufacturing and processing is relatively simple. The investment cost of the same equipment is only 11 million yuan per set, which can save users 4 million yuan per set in direct equipment investment costs.

[0050] The products extruded by the extruder with a single roller head have the characteristics of low extrusion temperature and low extrusion pressure. Two independent single-roller extruders are used to replace the structural type of two extruders + an internal compounding head to realize the extrusion of two products with different formulas, and then compound them outside the machine. The compounding mechanism 3 is arranged between the two single-roller extruders 2, which is used to compound the rubber materials extruded by the two single-roller extruders 2; wherein, the end of each screw extruder 21 is respectively provided with a roller 20 for extruding the rubber material into shape, and a cutting mechanism 22 for cutting the rubber material is provided 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, and the mechanism includes a lower roller 221 and two sets of independently driven cutter assemblies.

[0051] In addition, the use of low-temperature and low-pressure extrusion effectively solves the problem of premature vulcanization of rubber caused by high extrusion temperature, thereby reducing the extrusion temperature of rubber, ensuring compounding accuracy, and reducing the overall energy consumption of equipment operation, thereby improving the extrusion quality of composite treads from the source and providing support for tire companies to improve quality, reduce costs and increase efficiency.

[0052] Since a set of CNC cutter devices is installed at the head of each single roller, the extruded rubber can be cut into width according to the formula requirements, ensuring that the width size of each rubber block meets the requirements. In order to solve the problems of the accuracy of the bonding of the two rubber materials and the uncontrollable size caused by the shrinkage of different rubber materials, the rubber materials of thick products are pre-shrunk to ensure that the two rubber materials will not wrinkle or delaminate due to different shrinkage after bonding. During the centering and bonding process of the two rubber materials, two sets of CCD cameras are used to detect the position of the rubber materials at any time and control the overall left and right movement of the cutter, so as to ensure that the centering accuracy of the bonding of the two rubber materials is controlled within the process requirements.

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

[0054] Two CCD visual inspection cameras 223 are provided directly above the roller 201 , and the collection direction of the cameras is directly above the central axis of the roller 201 to align with the rubber material on the roller surface.

[0055] It is worth noting that two observation holes 224 are provided on the single-roll extruder 2. Each observation hole 224 is located between the roller 20 and the visual inspection camera 223, thereby reducing the imaging range of the camera and improving the response speed.

[0056] The camera and cutter servo system are connected via industrial Ethernet to analyze the edge position data of the rubber material in real time.

[0057] After the rubber material is cut by the cutting mechanism 22 , it enters the compounding mechanism 3 via the conveying rollers 201 provided at the rear sides of the two cutting mechanisms 22 .

[0058] When the base rubber material extruded from the upper extruder is formed into a strip by the roller, the visual camera 223 detects that the rubber material shrinks, causing the right edge to deviate from the designed position. The control system immediately drives the right cutter 222 to move left to compensate and cut, so that the rubber material width is precisely maintained at the desired position.

[0059] The cut rubber blocks fall onto the conveying roller 201 below. The two conveying rollers run at the same speed to synchronously convey the two rubber materials to the compounding mechanism 3.

[0060] The composite mechanism 3 includes two auxiliary rollers 31 whose axes are perpendicular to the conveying direction of the conveying roller 201 and a composite roller 32. The composite roller 32 consists of a rotatable shaft roller 321 and a cylindrical pressure roller 322 sleeved on the shaft roller. The pressure roller 322 consists of a plurality of disc-shaped roller sheets 323 sleeved on the shaft roller 321. The axial length of the roller sheet 323 is smaller than the axial length of the shaft roller 321 and its position on the shaft roller 321 is adjustable. A circular hole 324 is provided in the middle of the roller sheet 321, and the diameter of the circular hole 324 is larger than the diameter of the pressure roller 32.

[0061] The compounding mechanism 3 is located between the two single-roll extruders and includes two diameter auxiliary rollers 31 and a compounding roller 32 .

[0062] The surface of the auxiliary roller 31 is coated with silicone to increase the friction coefficient and ensure smooth transfer of the rubber material. The composite roller's shaft 321 is made of high-strength alloy steel and secured at both ends by hydraulic bearing blocks. Several 304 stainless steel rollers 323 are mounted on the shaft. The inner diameter of the circular holes 324 of the rollers 323 is 2mm larger than the shaft diameter, allowing the rollers to move up and down along the shaft. The rubber material is compacted by a specially designed gravity-driven multi-piece pressure roller, ensuring bonding strength while preventing deformation of the rubber from the pressing device.

[0063] A discharge port is provided on the other side of the composite mechanism 3 to transport the composite-molded tire tread to the next process.

[0064] When producing a 215 / 55R17 specification tread, due to the undulating slope on the tread, when the rubber passes through, the roller 323 can move up and down according to the height fluctuation, which can ensure automated production while also compacting the tire shoulder area to ensure high-strength bonding of the tread.

[0065] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A low-temperature, high-efficiency tread extrusion and off-machine compounding device, comprising: Body (1); A single-roll extruder (2), wherein two single-roll extruders (2) are provided, each single-roll extruder (2) comprises a screw extruder (21) for conveying rubber material, and the axes of the two screw extruders (21) are parallel; A compounding mechanism (3), the compounding mechanism (3) being arranged between the two single-roll extruders (2) and being used for compounding the rubber materials extruded by the two single-roll extruders (2); The end of each screw extruder (21) is provided with a roller (20) for extruding the rubber material into shape, and a cutting mechanism (22) for cutting the 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) via a conveying roller (201) provided at the rear side of the two cutting mechanisms (22).

2. A low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 1, characterized in that: The single-roll extruder (2) further comprises a feeder (23), and a feeding funnel (211) is provided above the starting section of the screw extruder (21), and the end of the feeder (23) is located directly above the feeding funnel (211).

3. The low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 1, characterized in that: A screw is provided inside the screw extruder (21), and a plurality of 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 of the screw extruder (21), and a notch is provided on the screw at a position corresponding to the pin (212).

4. A low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 3, characterized in that: The plurality of pins (212) are divided into a plurality of groups, and the plurality of groups of pins (212) are arranged at intervals on the outer end surface of the screw extruder (21), and each group of pins (212) is distributed in a ring shape on the outer end surface of the screw extruder (21).

5. The low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 1, characterized in that: The cutting mechanism (22) comprises a lower roller (221) parallel to the roller (20), and two cutters (222) are arranged above the lower roller (221), and the distance and height between the two cutters (222) are adjustable.

6. The low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 5, characterized in that: Two visual inspection cameras (223) for collecting image information of the rubber material on the roller (20) are provided directly above the roller (20). The visual inspection cameras (223) are communicatively connected with the driving mechanisms for controlling the movement of the cutters (222) in the two single-roller extruders (2).

7. The low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 6, characterized in that: The single-roll extruder (2) is provided with two observation holes (224), and each observation hole (224) is located between the roller (20) and the visual inspection camera (223).

8. The low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 7, characterized in that: The composite mechanism (3) comprises two auxiliary rollers (31) whose axes are perpendicular to the conveying direction of the conveying roller (201) and a composite roller (32). The composite roller (32) is composed of a rotatable shaft roller (321) and a columnar pressure roller (322) sleeved on the shaft roller.

9. The low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 8, characterized in that: The pressure roller (322) is composed of a plurality of disc-shaped roller sheets (323) sleeved on the shaft roller (321); the axis length of the roller sheet (323) is smaller than the axis length of the shaft roller (321), and its position on the shaft roller (321) is adjustable.

10. The low-temperature and high-efficiency tread extrusion and off-machine compounding device according to claim 9, characterized in that: A circular hole (324) is provided in the middle of the roller sheet (321), and the diameter of the circular hole (324) is larger than the diameter of the pressure roller (32).

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