Roller structure for hot-pressing aramid paper, hot-pressing equipment comprising roller structure and hot-pressing preparation method of aramid paper

Abstract

The invention discloses a roller structure for hot-pressing aramid paper, hot-pressing equipment comprising the roller structure and a hot-pressing preparation method of the aramid paper. The roller structure comprises a first controllable medium-height roller, a first heating roller, a second heating roller and a second controllable medium-height roller which are vertically aligned and sequentially distributed; the rotating directions of the first controllable medium-height roller and the first heating roller are opposite; the rotating directions of the first heating roller and the second heating roller are opposite; and the rotating directions of the second heating roller and the second controllable medium-height roller are opposite. Aramid paper to be subjected to hot pressing sequentially passes through a first pressing area between the first controllable medium-height roller and the first heating roller, a second pressing area between the first heating roller and the second heating roller and a third pressing area between the second heating roller and the second controllable medium-height roller to be subjected to hot pressing. According to the invention, uniform thickness of the aramid paper product can be ensured, deformation and internal stress of the aramid paper are reduced, product quality is improved, post-treatment is avoided, efficiency is improved, and production cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of aramid paper manufacturing, in particular to a roller structure for hot-pressing aramid paper, hot-pressing equipment comprising the roller structure, and a hot-pressing preparation method for aramid paper. Background Art

[0002] In recent years, aramid paper has been widely used in the insulation of automobiles, motors, transformers, and electronic appliances. It can also be further processed into honeycomb structure materials as an important component of aircraft, high-speed railways, and EMUs.

[0003] Currently, aramid paper is hot-pressed using a two-roller system, with the upper rollers being cross-shaped and the lower rollers being fixed at a fixed height. To expand its range of applications, the fixed height is set to the minimum possible value, and the thickness of the paper is adjusted by the cross-shaped arrangement of the upper rollers. However, the existing hot-pressing method for aramid paper presents the following problems:

[0004] 1. Thickness deviation problem: Due to the use of fixed mid-height and cross-adjustment of thickness, the thickness curve of the product will be the same as the fitted fixed curve instead of a straight curve, which will cause deviation in the thickness of the product.

[0005] 2. Lateral deformation problem: When using cross adjustment, half of the aramid paper will contact the paper first and the other half will contact the paper later during the production process. This is equivalent to hot pressing half of the paper first and the other half later. This will cause lateral deformation, especially for wet paper.

[0006] 3. Product deformation and internal stress problems: Due to cross-adjustment, the product may be deformed, resulting in internal stress in the product, affecting product quality.

[0007] 4. Limitations of hot-pressing temperature and pressure: During the hot-pressing process, the synergistic effects of force and heat are required to effectively improve the structure and properties of aramid paper. After hot-pressing, the structure of aramid paper becomes denser and its porosity decreases, but the chemical structure remains unchanged. Furthermore, the degree of intermolecular hydrogen bonding in aramid precipitated paper increases. This indicates that traditional methods do not fully utilize the potential of the hot-pressing process.

[0008] In summary, the traditional hot pressing cross-adjustment method for aramid paper has multiple defects, including thickness deviation, lateral deformation, product deformation and internal stress problems, as well as limitations of hot pressing temperature and pressure. These problems limit the further improvement of aramid paper performance. Therefore, the product usually undergoes a further heat treatment after hot pressing.

[0009] A mid-height roller is a rubber roller with a slightly larger diameter in the middle section than at its ends. This raised portion of the roller's middle section compensates for deformation caused by roller deflection during operation. The mid-height roller market has rapidly evolved from fixed mid-height rollers to controllable mid-height rollers, and then to zoned and shoe-type controllable mid-height rollers. The controllable mid-height roller design allows the roller's mid-height to be adjusted to suit varying processing requirements and material properties. This adjustment can be achieved through hydraulic systems or motor-driven mechanical systems, dynamically changing the mid-height during operation, making it suitable for a wide range of applications. Summary of the Invention

[0010] Due to the above-mentioned defects in the prior art, the present invention provides a roller structure for hot-pressing aramid paper, a hot-pressing device containing the same, and a hot-pressing preparation method for aramid paper, which can ensure the uniformity of the thickness of the aramid paper product, reduce the deformation and internal stress of the aramid paper, and improve product quality.

[0011] To achieve the above objectives, in a first aspect, the present invention provides a roller structure for hot-pressing aramid paper, comprising a first controllable mid-height roller, a first heating roller, a second heating roller, and a second controllable mid-height roller, which are vertically aligned and sequentially distributed; the first controllable mid-height roller and the first heating roller rotate in opposite directions; the first heating roller and the second heating roller rotate in opposite directions; and the second heating roller and the second controllable mid-height roller rotate in opposite directions.

[0012] The aramid paper to be hot-pressed passes through the first pressing zone between the first controllable middle-height roller and the first heating roller, the second pressing zone between the first heating roller and the second heating roller, and the third pressing zone between the second heating roller and the second controllable middle-height roller for hot pressing.

[0013] Using the technical solution of the present invention, the aramid paper to be hot-pressed is subjected to single-sided flat hot pressing in the first and third nips, respectively, using a controllable mid-height roller and a heated roller. Adjustment of the controllable mid-height roller ensures uniform product thickness without causing deformation or internal stress. Simultaneously, in the second nip, because the two heated rollers are supported by upper and lower controllable mid-height rollers, their displacement is minimal, virtually eliminating product deformation, thereby improving the quality of the aramid paper. Furthermore, the controllable mid-height rollers allow precise control of paper thickness during the hot pressing process by adjusting the mid-height, which is crucial for producing aramid paper with specific thickness requirements. This allows for adaptability to varying production conditions and paper properties, improving the adaptability and flexibility of the production line.

[0014] Furthermore, the first controllable mid-height roller and the second controllable mid-height roller are hydraulically controllable mid-height rollers or mechanically controllable mid-height rollers, respectively.

[0015] Furthermore, both ends of the first controllable mid-height roller, the first heating roller, the second heating roller and the second controllable mid-height roller are provided with independent supporting structures to ensure the stability of the roller positions of the rollers.

[0016] Furthermore, the set temperature of the first and second controllable mid-height rollers is lower than the set temperature of the first and second heating rollers. This technical solution, combining zoned flat hot pressing with low temperatures at both ends and high temperatures in the middle, can further increase the density of the aramid paper after hot pressing, improving the overall performance of the paper.

[0017] In a second aspect, the present invention further provides a hot pressing device for aramid paper, comprising an unwinding mechanism, a preheating guide mechanism, the roller structure as described above, and a winding mechanism, which are connected in sequence.

[0018] Furthermore, the unwinding mechanism is provided in several sets according to the quantity of the aramid paper raw materials.

[0019] Furthermore, a traction mechanism is provided between the roller structure and the winding mechanism to shape the aramid paper after heat pressing.

[0020] In a third aspect, the present invention also provides a hot pressing preparation method for aramid paper, which uses the hot pressing equipment as described above to hot press the aramid paper; first, several portions of aramid paper raw materials are pulled out through a unwinding mechanism, then preheated and guided through a preheating guiding mechanism, and then hot-pressed through a first pressing area, a second pressing area, and a third pressing area in sequence, and then wound up through a winding mechanism.

[0021] Furthermore, the hot-pressed aramid paper is wound after being traction-processed.

[0022] Compared with the prior art, the above invention has the following advantages or beneficial effects:

[0023] This invention utilizes a multi-zone hot pressing scheme that utilizes a unique combination of controllable mid-height rollers and heated rollers. This not only ensures uniform product thickness while effectively preventing deformation and internal stress, thereby improving the quality of aramid paper, but also eliminates the traditional post-press heat treatment step for aramid paper, reducing production costs. Furthermore, the two controllable mid-height rollers enable convenient online adjustment of paper thickness, improving the production line's efficiency, adaptability, and flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention and its features, configurations, and advantages will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings. Like reference numerals indicate like parts throughout the drawings. The drawings are not necessarily drawn to scale, emphasis instead being placed on illustrating the subject matter of the present invention.

[0025] Figure 1A schematic front view of the overall structure of a roller structure provided by one embodiment of the present invention;

[0026] Figure 2 A schematic diagram of the overall structure of a hot pressing device provided in one embodiment of the present invention;

[0027] Figure 3 for Figure 2 Schematic top view of the unwinding mechanism, roller structure and traction processing mechanism;

[0028] Among them, 1. unwinding mechanism; 2. preheating guide mechanism; 3. winding mechanism; 4. supporting structure; 5. traction processing mechanism; 11. first controllable middle and high roller; 12. second controllable middle and high roller; 21. first heating roller; 22. second heating roller; 31. first pressing area; 32. second pressing area; 33. third pressing area. DETAILED DESCRIPTION

[0029] The structure of the present invention is further described below with reference to the accompanying drawings and specific embodiments, but is not intended to limit the present invention.

[0030] In the description of the present invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first," "second," "third," etc. may explicitly or implicitly include one or more of such features.

[0031] In addition, the device structure and drawings of the present invention mainly describe the principles of the present invention. In terms of the technology of the design principle, the settings of the power mechanism, power supply system and control system of the device are not fully described. On the premise that those skilled in the art understand the principles of the above invention, they can clearly know the details of its power mechanism, power supply system and control system. The control method of the application document is automatic control through a controller, and the control circuit of the controller can be realized by simple programming by those skilled in the art. The standard parts used therein can be purchased from the market, and can be customized according to the description and drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. Machinery, parts and equipment all adopt conventional models in the prior art, and the components known to those skilled in the art, their structures and principles are all known to those skilled in the art through technical manuals or through conventional experimental methods.

[0032] Example

[0033] See Figures 1 to 3 This embodiment provides a roller structure for hot pressing aramid paper and a hot pressing device containing the roller structure. Figure 1The roller structure includes a first controllable mid-height roller 11, a first heating roller 21, a second heating roller 22, and a second controllable mid-height roller 12, all aligned and arranged vertically. The first controllable mid-height roller 11 rotates in opposite directions to the first heating roller 21; the first heating roller 21 rotates in opposite directions to the second heating roller 22; and the second heating roller 22 rotates in opposite directions to the second controllable mid-height roller 12. The first controllable mid-height roller 11 and the second controllable mid-height roller 12 can be hydraulically or mechanically controlled, respectively. For example, the hydraulic system of a hydraulically controllable mid-height roller includes components such as a hydraulic pump, a proportional relief valve, an accumulator, and a hydraulic cylinder. These components work together to precisely control the roller pressure. The proportional relief valve is the component in the system that implements the variable loading function, and its pressure adjustment is proportional to the input electrical signal. The hydraulic cylinder adjusts the roller's mid-height using the pressure of the hydraulic oil to control the paper thickness.

[0034] As a preferred technical solution, independent support structures 4 are provided at both ends of the first controllable middle and high roller 11, the first heating roller 21, the second heating roller 22 and the second controllable middle and high roller 12 to ensure the stability of the roller position of each roller.

[0035] The aramid paper to be hot pressed passes through the first pressing zone 31 between the first controllable middle and high roller 11 and the first heating roller 21, the second pressing zone 32 between the first heating roller 21 and the second heating roller 22, and the third pressing zone 33 between the second heating roller 22 and the second controllable middle and high roller 12 for hot pressing.

[0036] The aramid paper to be hot-pressed passes through a controllable mid-height roller and a heated roller in the first and third nips, respectively, for single-sided flat hot pressing. Adjustment of the controllable mid-height rollers ensures uniform product thickness, preventing deformation or internal stress. Meanwhile, in the second nip, because the two heated rollers are supported by upper and lower controllable mid-height rollers, their displacement is minimal, virtually eliminating product deformation, thereby improving the quality of the aramid paper. Furthermore, the controllable mid-height rollers allow precise control of paper thickness during the hot-pressing process by adjusting the mid-height, which is crucial for producing aramid paper with specific thickness requirements. They can also adapt to varying production conditions and paper properties, improving the adaptability and flexibility of the production line.

[0037] As a preferred technical solution, the set temperature of the first controllable mid-height roller 11 and the second controllable mid-height roller 12 is lower than that of the first heating roller 21 and the second heating roller 22. This technical solution, combining zoned flat hot pressing with low-temperature zones at the end and high-temperature zones in the middle, can further improve the density of the aramid paper after hot pressing, enhancing the overall performance of the paper. It should be noted that the maximum hot pressing temperature is closely related to the number of aramid paper layers and the thickness of the product. Establishing a temperature gradient between the end zones and the middle zone can significantly optimize the compaction performance of the roller structure in this embodiment.

[0038] See also Figure 2 and Figure 3 The aramid paper hot pressing equipment of this embodiment includes an unwinding mechanism 1, a preheating guide mechanism 2, the roller structure as described above, and a winding mechanism 3 which are connected in sequence.

[0039] The unwinding mechanism 1 is provided with several sets according to the quantity of the aramid paper raw materials. For example, Figure 2 There are three sets of unwinding mechanisms in the machine.

[0040] As a preferred technical solution, a traction mechanism 5 is further provided between the roller structure and the winding mechanism 3 to shape the aramid paper after heat pressing.

[0041] The method for hot-pressing aramid paper raw materials using the hot-pressing apparatus described above includes: first, several portions of aramid paper raw materials are drawn out through an unwinding mechanism 1, then preheated and guided through a preheating and guiding mechanism 2, and then sequentially passed through a first nip 31, a second nip 32, and a third nip 33 for hot pressing, before being reeled up by a reeling mechanism 3. Furthermore, the hot-pressed aramid paper can be reeled up after being pulled through a traction process.

[0042] In summary, the present invention provides a roller structure for hot-pressing aramid paper, hot-pressing equipment including the same, and a method for hot-pressing aramid paper. The roller structure comprises a first controllable mid-height roller, a first heated roller, a second heated roller, and a second controllable mid-height roller, all vertically aligned and sequentially arranged. The first controllable mid-height roller rotates in opposite directions to the first heated roller; the first heated roller rotates in opposite directions to the second heated roller; and the second heated roller rotates in opposite directions to the second controllable mid-height roller. The aramid paper to be hot-pressed passes sequentially through a first nip between the first controllable mid-height roller and the first heated roller, a second nip between the first heated roller and the second heated roller, and a third nip between the second heated roller and the second controllable mid-height roller. This invention ensures uniform thickness of aramid paper products, reduces deformation and internal stress in the aramid paper, improves product quality, and avoids post-processing, thereby improving efficiency and reducing production costs.

[0043] Those skilled in the art should understand that they can implement variations by combining the prior art with the above embodiments, which will not be described in detail here. Such variations do not affect the essence of the present invention and will not be described in detail here.

[0044] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-mentioned disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, or modify them into equivalent embodiments of equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention that do not depart from the content of the technical solutions of the present invention are still within the scope of protection of the technical solutions of the present invention.

Claims

1. A roller structure for hot pressing aramid paper, characterized in that: The invention comprises a first controllable middle-height roller (11), a first heating roller (21), a second heating roller (22) and a second controllable middle-height roller (12) which are vertically aligned and sequentially distributed; the first controllable middle-height roller (11) and the first heating roller (21) rotate in opposite directions; the first heating roller (21) and the second heating roller (22) rotate in opposite directions; the second heating roller (22) and the second controllable middle-height roller (12) rotate in opposite directions; The aramid paper to be hot-pressed is sequentially passed through a first pressing zone (31) between the first controllable middle-height roller (11) and the first heating roller (21), a second pressing zone (32) between the first heating roller (21) and the second heating roller (22), and a third pressing zone (33) between the second heating roller (22) and the second controllable middle-height roller (12) for hot pressing.

2. The roller structure for hot pressing aramid paper according to claim 1, characterized in that: The first controllable medium-high roller (11) and the second controllable medium-high roller (12) are respectively hydraulically controllable medium-high rollers or mechanically controllable medium-high rollers.

3. The roller structure for hot pressing aramid paper according to claim 1, characterized in that: Both ends of the first controllable middle-height roller (11), the first heating roller (21), the second heating roller (22), and the second controllable middle-height roller (12) are provided with mutually independent support structures (4).

4. The roller structure for hot pressing aramid paper according to claim 1, characterized in that: The set temperatures of the first controllable middle-height roller (11) and the second controllable middle-height roller (12) are lower than the set temperatures of the first heating roller (21) and the second heating roller (22).

5. A hot pressing device for aramid paper, characterized in that: It comprises an unwinding mechanism (1), a preheating guiding mechanism (2), a roller structure according to any one of claims 1 to 4, and a winding mechanism (3) which are connected in sequence.

6. The hot pressing equipment for aramid paper according to claim 5, characterized in that: The unwinding mechanism (1) is provided in several sets according to the quantity of the aramid paper raw materials.

7. The hot pressing equipment for aramid paper according to claim 5, characterized in that: A traction mechanism (5) is further provided between the roller structure and the winding mechanism (3) to shape the aramid paper after heat pressing.

8. A hot pressing method for preparing aramid paper, characterized in that: Aramid paper is hot-pressed using the hot-pressing equipment as described in claim 5 or 6; first, a plurality of aramid paper raw materials are pulled out through a reeling mechanism (1), then preheated and guided through a preheating guiding mechanism (2), and then hot-pressed through a first pressing area (31), a second pressing area (32), and a third pressing area (33) in sequence, and then reeled through a reeling mechanism (3).

9. The hot-pressing preparation method of aramid paper according to claim 8, characterized in that: The hot-pressed aramid paper is drawn and then rolled up.

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