Hot pressing tool, hot pressing apparatus having the hot pressing tool, and method of hot pressing a preform

Abstract

The invention relates to a tool part (640), a hot-pressing device (610) and a method for hot-pressing a preform made of a fiber-containing material, wherein the hot-pressing device (610) has a first tool part (640) with a first tool body (642) and at least one first molding device (670) and a second tool part (690) with a second tool body (692) and at least one second molding device (694). The method comprises: providing at least one preform made of a fiber-containing material; heating at least the first tool body (640) and the at least one first molding device (670) via at least one first temperature control device; placing the at least one preform onto a first contact surface (676) of the at least one first molding device (670); moving the second tool part (690) relative to the second tool part (640).

Description

Technical Field

[0001] This invention describes a tool component for a hot pressing apparatus, a hot pressing apparatus, and a method for hot pressing a preform made of a fiber-containing material.

[0002] Fiber-containing materials are increasingly used, for example, in the manufacture of food packaging (such as bowls, capsules, boxes, etc.) and consumer product packaging (such as electronic devices) as well as beverage containers. These fibrous materials typically contain natural fibers, which may be derived from renewable resources or waste paper. The natural fibers are mixed with water and possibly other additives, such as starch, in a so-called pulp. Furthermore, additives may affect color, shielding properties, and mechanical properties. This pulp may contain, for example, 0.5 to 10% by weight of natural fibers. The proportion of natural fibers depends on the process used to manufacture the packaging and the characteristics of the product being manufactured. Background Technology

[0003] Typically, the production of fiber-containing products from pulp involves several steps. First, the pulp is provided as a raw material, and a suction unit with a suction tool, whose geometry substantially matches the product to be manufactured, is at least partially immersed in the pulp. During immersion, suction is performed through an opening in the suction tool, which is connected to a corresponding device, during which fibers from the pulp aggregate onto the suction tool. These fibers are then carried through the suction tool into a pre-pressing tool, where they form a preform. In this pre-pressing process, the fibers are pressed into the preform, and the moisture content of the preform decreases.

[0004] In subsequent steps, the preform is typically pressed into a finished product using a hot press. Here, the preform is fed into a hot press tool, which consists of a lower and an upper section, both of which are heated. Within the hot press tool, the preform is pressed into a cavity under heat, where residual moisture is forced out by pressure and heat, resulting in a preform containing approximately 60% residual moisture by gravity, which after hot pressing has only, for example, 5% residual moisture by gravity. Water vapor generated during hot pressing is expelled through openings in the cavity and channels of the hot press tool. A suction device to create a relative vacuum is designed for this purpose. This suction is typically accomplished by the lower section of the tool. A vacuum pump or another device serving the same function is designed and fluidly connected to the openings in the cavity.

[0005] Hot pressing tools and manufacturing processes using the above-described hot pressing method are known, for example, from patent DE 10 2019 127 562 A1.

[0006] Crucially, in hot pressing, the preforms with high moisture content must be sufficiently heated and pressed for a long enough time to achieve the desired residual moisture in the finished product and to compress the fibers. This typically requires very long cycle times for each hot pressing process to ensure that all preforms contained within the hot pressing tool meet the required maximum residual moisture content.

[0007] However, excessively long compression times waste cycle time, resulting in longer cycles than actually needed. If the selected cycle time is too short, not all preforms in the hot press will be adequately heated and compressed, forcing some preforms to be discarded as scrap due to excessive moisture and / or damage. For example, overly moist preforms may remain "stuck" to the hot press tool when it is opened, and / or at least partially torn, causing damage.

[0008] It has been found that, especially when the hot press tool has multiple cavities in which preforms are placed, the cavities initially heated by a temperature control device, as well as the tool components that at least partially constitute these cavities, experience varying degrees of temperature fluctuations during hot pressing. Thus, for example, the high moisture content of the preform significantly affects the temperature of the cavity contact surfaces. Since the preform may have different moisture contents before hot pressing, this also leads to varying degrees of "cooling" of the cavities and the hot press tool. Furthermore, it has been found that the surface temperature of the cavity contact surfaces varies considerably for each cavity, depending on its location within the hot press tool.

[0009] Furthermore, it has been found that if the closing speed of the hot press tool, i.e. the speed at which the two tool parts of the hot press tool move relative to each other, is not adapted to the discharge of water from the preform, less water will be produced relative to the (local) evaporable moisture, thus making the energy drawn away insufficient to cool the surface temperature to the boiling point (surface temperature > boiling point), thereby “wasting” cycle time.

[0010] Furthermore, the closing rate of water generation within the cavity cannot be adjusted, resulting in the release of more water than (locally) could evaporate within a given time window. The heat absorbed from the cavity causes the surface temperature of the contact surfaces to cool below the typical boiling point of the fibrous material under the dominant pressure (surface temperature < boiling point temperature). Therefore, the cycle time / cycle cannot be used efficiently because the cavity surface is overcooled. Thus, the cycle time must be increased.

[0011] Furthermore, excessively rapid closure may lead to excessively rapid steam generation, creating localized "steam pads." Here, the spherical diffusion of steam within the enclosed localized space of the cavity, accompanied by increased pressure, could potentially cause the preform contained within to rupture. Additionally, steam may be unable to escape sufficiently quickly through existing openings due to "blockage," and the increased pressure may also raise the boiling point of water, or liquids carried in the preform's slurry, making the finished product appear "wetter" because insufficient energy can be carried away from the cavity surface. "Blockage" refers to blocking or closing openings and / or channels, for example, when the generated steam exceeds the amount that can be discharged. Summary of the Invention

[0012] Therefore, there is significant potential for improvement in the manufacture of products using fibrous materials, particularly in the hot pressing process and the necessary tools. To date, it has not been possible to solve the aforementioned problem—namely, to adequately heat the preform within a correspondingly short cycle time, thereby reducing waste—using known tools and methods.

[0013] Therefore, the object of the present invention is to provide a hot pressing tool and a method that can provide hot-pressed preforms (finished products) made of fibrous materials, which do not exceed a predetermined residual moisture content, while generating no waste, or at least generating less waste compared to known methods and hot pressing tools. Furthermore, cycle time should be optimized to avoid wasting resources in terms of time, energy, and material turnover.

[0014] The aforementioned task is solved by a tool component for a hot pressing apparatus, having a first tool body having at least one first molding device on at least one side, the molding device having a first contact surface for a preform to be accommodated, wherein the first tool body is made of a thermally conductive material and has a first temperature regulating device configured to regulate the temperature of the first tool body and the at least one first molding device, wherein the at least one first molding device has a first opening on the first contact surface for the preform to be accommodated, these openings leading to at least one first channel in the first tool body, wherein the at least one first channel leads from the first opening to at least one first interface.

[0015] At least one second opening is designed here, which provides fluid connection to the first opening of the at least one first molding device, separate from the at least one first interface.

[0016] Generally, it has been found that the surface temperature of the cavity formed between the first and second contact surfaces of at least one complementary second molding device, particularly the surface temperatures of the first and second contact surfaces, drops drastically regardless of the initial temperature level at the start of the cycle, due to excess water or liquid or fluid from the slurry in the preform generated by the closing force. Therefore, a hot pressing device with a hot pressing tool (having a first tool assembly, such as the lower half of a tool, and a second tool assembly, such as the lower half of a tool) cannot function effectively when the surface temperature of the contact surfaces of at least one cavity drops below a critical level for the hot pressing process, because the excess water cannot evaporate. Here, the first and second tool components can be configured such that the cavity is tightly closed during hot pressing. This saves energy during hot pressing because, for example, no water vapor escapes, thus preventing cooling of the cavity. For this purpose, the first molding device and the cooperating second molding device can be constructed accordingly, and they can be pressed together with corresponding force during hot pressing. In a further embodiment, a partial unsealing can be intentionally designed to create a second opening in the cavity between the first molding device and the second molding device, which can thus provide a "secondary airflow" for example when venting water vapor formed in the suction cavity.

[0017] In a hot press tool, a cavity is formed between the first contact surface of the first molding device in the first tool component and the second contact surface of the second molding device in the second tool component.

[0018] When the first and second tool components of the hot pressing tool are compressed, excess moisture or fluid from the slurry of the primary product (preform) flows to the surface / contact surface of the cavity and evaporates when the surface temperature is sufficiently high, which may also cause a brief drop in temperature level. In the subsequent process, the material capacity of the tool components directly in contact with the surrounding area provides heat to the area near the surface, and thus very quickly restores the contact surface to an average level corresponding to the required total power. The first tool body and molding device can therefore be made of, for example, metal or metal alloy, and here have good thermal conductivity. For example, the first tool body and the at least one first molding device are made of aluminum; other metals and metal alloys are also suitable. In selecting materials, the temperature to be achieved, the heat storage capacity (capacity) of the material, and the composition of the slurry and its components must also be considered. The first tool body and the at least one molding device may also have, for example, a coating that serves both to protect the surface from damage and / or to interact with one of the components of the slurry / water and / or the tool device.

[0019] The coating can also protect sensor elements on the surface of the first tool body and / or on the first contact surface of the at least one first molding device. Furthermore, the properties of the coating can be adapted to suit the requirements of the tool.

[0020] Furthermore, the at least one molding device can be an integral part of the first tool body. Thus, for example, the at least one molding device can be designed as a protrusion or recess in the first tool body, and the recess and protrusion of the product to be manufactured can be produced therein.

[0021] In a further embodiment, the at least one first molding device can be interchangeably connected to the first mold body. For this purpose, both the first tool body and the at least one first molding device have mating fasteners. For example, the connection between the first molding device and the at least one first tool body can be achieved via screws, through the fasteners between the first tool body and the at least one first molding device. These fasteners can be, for example, openings with or without threads, bolts, hooks, slide rails, etc.

[0022] Traditionally, hot pressing tools and related tooling components typically have multiple molding devices or cavities, allowing for the simultaneous production of multiple products during the hot pressing process. When multiple cavities or molding devices are present, the aforementioned problems become more pronounced, such as differences in moisture content of the preform, temperature fluctuations on the surface of the cavity or molding device due to different locations, and the resulting differences in pressure and temperature, which can lead to different evaporation processes and thus "clogging." Furthermore, multiple first channels can be designed in the first tooling component, each with a flow path of varying length to the exhaust device, thereby further affecting the state within the cavities and first channels.

[0023] The proposed tool component provides a solution to the aforementioned problem through the at least one second opening, particularly in cases with multiple first molding devices or cavities. The second opening, while spaced apart from the at least one first interface, is fluidly connected to the first opening of the at least one first molding device, thus preventing "blockage" within the cavities and ensuring consistent boiling point regulation of the fluids in different cavities through pressure equalization within all cavities. This prevents differences in boiling points within cavities due to large temperature variations, thereby avoiding increased localized temperature differences within the cavities (which are caused by the cavity's position on the tool body and are related to the proximity between cavities), and thus minimizing the impact on hot pressing. Therefore, the proposed solution provides the possibility of determining a cycle time for the hot pressing process that is long enough for all preforms produced simultaneously, thus avoiding wasted cycle time.

[0024] The fluid (gaseous or liquid) generated from the slurry during the hot pressing process can be drawn away or otherwise discharged through the at least one first channel via the first opening. The fluid is typically water evaporated on the hot surface of the cavity. Therefore, water vapor is typically discharged from the cavity. For this purpose, a corresponding device (e.g., a vacuum pump) can be connected to the first interface. The discharge of the fluid (wherein "fluid" includes not only gaseous but also liquid substances, and also represents water and aqueous solutions from the slurry) can be accomplished, for example, at a pressure below ambient pressure. For example, the vacuum thus provided can have an absolute pressure of 0.2 to 0.9 bar. The at least one second opening provides fluid connection to the surrounding environment, a gas or gas mixture reservoir, or equipment for supplying the gas or gas mixture (pump, radial compressor, etc.) while discharging, for example, water vapor, through the first opening. Therefore, not only is gaseous and / or liquid fluid drawn away from the cavity, but also gas or gas mixtures, such as ambient air, are simultaneously drawn in. This makes it possible to adjust the pressure in the at least one first channel and in all chambers to balance it with the ambient pressure or the gas / mixed gas pressure, which may differ from the ambient pressure depending on the supply method (e.g., due to supply by a compressor).

[0025] According to the definition chosen here, even if the "closed" connection only exists when the first and second tooling components are in a closed state, a fluid connection exists between the second opening (e.g., formed by a guide groove) and the first opening within the connection area between the first and second molding devices. This means that the connection in the tooling components also exists along the contact surface via the surface of the first molding device. Here, the at least one second opening may be formed by a recess in the contact area of ​​the first molding device and / or the second molding device having a complementary structure, thereby eliminating the need for a closed crimping edge for the at least one second opening.

[0026] Because additional gas, gas mixture, or ambient air is drawn in, fluid extraction can be performed at different pressures via a first opening in the first contact surface or from the at least one cavity. For example, because gas, gas mixture, or ambient air is drawn in simultaneously, extraction and extraction can be performed at a slightly low pressure (less than 1 bar) via the at least one first interface.

[0027] In general, what is achieved by providing a secondary flow of gas or a mixture of gases (wherein the mixture also includes ambient air) is that no “blockage” occurs because, for example, more “vapor volume” can be discharged from the cavity compared to the usual low pressure.

[0028] Therefore, for example, at volumetric flow near ambient pressure (approximately 1 bar), more "vapor volume" is removed than at lower pressures (e.g., 0.5 bar). If the supply gas or gas mixture has a higher pressure (greater than 1 bar), there is a greater likelihood of, for example, water vapor being expelled or drawn from the cavity. Among other factors, the saturation of the water in the inlet is also crucial. The lower the saturation, the more water can be drawn from the cavity, resulting in more water being expelled or removed. Furthermore, when the amount of gas or gas mixture supplied via the inlet increases, or the pressure of the gas or gas mixture increases, the ability to expel moisture evaporated at the hot contact surfaces of the cavity per unit time increases.

[0029] The enthalpy of vaporization of the fluid (especially water) from the slurry is essentially independent of the temperature level in the cavity and is many times higher than the energy required to heat it to the evaporation temperature. Therefore, it is advantageous to remove the generated water vapor at as much effective pressure as possible.

[0030] In summary, the tool components described herein enable consistent regulation of the boiling point within the cavity of the hot pressing tool while achieving pressure equilibrium in the discharge channel (at least one first channel). This allows for a significant increase in the volume of fluid discharged from the preform without affecting the cycle time. The proposed solution significantly improves the hot pressing process, thereby enhancing the final fabrication of fibrous material products, with relatively low overhead.

[0031] The first interface of the first channel can be implemented in different forms. Thus, the first interface can only have a connection to another channel outside the first tool body. In a further embodiment, the first connector can have a connecting element for engagement with a mating connecting element. In a further embodiment, the at least one first interface can also have a valve, which is adjustable for suction and vacuum supply.

[0032] The at least one second opening may be provided on the first tool body and / or at least one first molding device. As described above, the at least one second opening may be configured as a recess in the contact area of ​​the first molding device, which provides fluid connection between the opening and the corresponding first opening on the first contact surface when connected to the second molding device. These second openings may be constructed in the form of relatively small, circular, elliptical, or slotted openings. As with other second openings, the opening width of these second openings is determined in such a way that the secondary flow of gas or mixed gas supplied within the cavity does not cause the dominant state there to collapse. Since these states depend on the size of the cavity, the moisture content of the preform, the cycle time, and the media involved, the description of the limitations on these states (especially temperature and pressure) (which in turn determine the size of the second opening) is not placed together with the opening width of the second opening. However, it is thus understood that the opening width of the at least one second opening depends on this and is determined accordingly. The at least one second opening may also be provided, for example, in the first tool body and fluidly connected to the at least one first channel and / or first opening.

[0033] In a further embodiment, the first tool body may have at least one second channel fluidly connected to the at least one first channel and the at least one second opening. In a still further embodiment, the at least one second channel may be fluidly connected to the surrounding environment, a gas or gas mixture reservoir, or a device (e.g., a compressor) for providing a gas or gas mixture bypass via at least one second connector in the first tool body.

[0034] The at least one second connector can be implemented in a different form than the first connector, for example, configured as an opening. A connecting element can also be designed on the at least one second connector to enable connection with a valve. In a further embodiment, the connecting element itself can also constitute the second connector.

[0035] Furthermore, in a further embodiment, the at least one second opening may also be connected to the surrounding environment, a gas storage device, or a device for providing gas or a gas mixture.

[0036] In a further embodiment, the tool component may have at least one adjusting element for adjusting the opening width of the at least one second opening. These adjusting elements are used to regulate the flow rate of the conveyed secondary flow. Depending on the specific embodiment, the adjusting element may be implemented as a valve or, for example, a baffle.

[0037] In a further embodiment, the at least one second opening and / or the at least one first channel may have at least one valve through which the flow rate of the delivered gas or mixed gas secondary stream can be controlled. Therefore, it can be adapted to different, measured or detected states in the cavities and / or channels of the mold body, different moisture contents of the preform, and / or different cavity arrangements of the corresponding products. The second connector may also be connected to or have a valve.

[0038] This allows for the adjustment of the amount of gas or gas mixture (e.g., ambient air) being drawn in. Consequently, it can significantly affect the amount of fluid (e.g., water vapor) discharged. Especially in the continuous monitoring of the hot pressing process, the amount of fluid discharged and the temperature in the cavity can be persistently adjusted, thereby regulating the boiling point and pressure in the channels or cavities of the tool components to suit a preset optimal state in terms of cycle time or periodicity.

[0039] In a further improvement, the adjusting element can be implemented, for example, as a baffle movably arranged on the first tool body, and having at least one opening that overlaps with at least one second opening in the neutral position. If the baffle is displaced or otherwise shifted (e.g., twisted, tilted, etc.), the opening width of the at least one second opening changes. For example, in an embodiment with multiple, particularly parallel, second channels, corresponding second openings are arranged on one side of the first tool body, and baffles with corresponding openings are movably arranged. By pushing the baffle, the opening width of all the second openings can be changed simultaneously. This can be done, for example, to adapt the opening width of the second openings to a new product or cavity, or to adapt to changes in the state of the cavity and / or changes in the properties of the prefabricated part. For example, the movement of the baffle can be performed manually by the operator, for which, for example, a locking element (such as a screw) can be loosened and can be relocked after a new setting, or it can be locked by a motor. Motor control can be based, for example, on measured, detected, and / or calculated values ​​of states and / or parameters.

[0040] In a further embodiment, the hot-pressing component may have multiple second channels extending within the first tool body. This, for example, results in a relatively large amount of fluid being discharged in a short time compared to conventional embodiments where the tool body has only one first channel and embodiments with only one second channel. Furthermore, "clogging" is further reduced, ensuring that the channels within the tool body have sufficient capacity to accommodate variable volumes of fluid or water vapor, even in the event of strong steam formation. Additionally, this ensures that the boiling point in the cavity and the pressure in the channels are balanced or at the same level.

[0041] In a further embodiment, the second channels may extend parallel to each other. Furthermore, the parallel-extending second channels may be connected to each other via, for example, connecting conduits that intersect with the second channels. This ensures that the drawn-in gas or gas mixture (e.g., ambient air) reaches the respective cavities of the tool component in sufficient quantity to allow fluid (e.g., water vapor) to be discharged without a short-term pressure rise in the channels. For example, a large amount of water vapor can be generated in a short period during hot pressing. The channels in the tool body are typically designed to have a relatively small diameter (e.g., in the range of 1 to 5 mm), so that only a limited amount of water vapor can be discharged per unit of time. For heat storage capacity reasons, the diameter of the second channels cannot be arbitrarily large, because otherwise the second channels would cool drastically due to the drawn-in ambient air (which is, for example, 20°C at normal room temperature), or due to the gas / gas mixture having a significantly different temperature, which would subsequently lead to cooling of the tool body and thus the first molding device, which operates, for example, in a temperature range of 150°C to 250°C. The more tightly the channels are interconnected, the better it ensures that sufficient water vapor can be discharged even during short-term peaks, and that localized pressure spikes do not occur within the chambers or channels. This also prevents localized increases in boiling point within individual chambers.

[0042] In a further embodiment, the channel extending within the tool body for discharging fluid (e.g., water vapor) from the preform can have a diameter that gradually increases toward the first interface. Precisely in configurations with multiple cavities, multiple channels typically extend within the tool body, terminating at a common first channel with a single first interface. This common first channel must dissipate a greater volume of evaporated fluid per unit time, as from the individual channels within the cavities, and therefore requires a correspondingly larger diameter. The diameter design can be determined here based on the construction of the tool body and the number and construction of the cavities or molding devices.

[0043] The aforementioned task is also solved by a hot pressing device having at least one first tool component and at least one second tool component according to the above embodiments, wherein the second tool component has a second tool body made of a thermally conductive material, and the second tool body has at least one second molding device on at least one side, which is complementary to the at least one first molding device, and has a second contact surface on its surface for accommodating a preform, such that when the at least one first tool component and the at least one second tool component are pressed together for hot pressing the preform, a cavity for accommodating the preform is formed between the first contact surface and the second contact surface, respectively.

[0044] The first and second tool components are designed such that they have mating molding devices that, in the closed state, form cavities for pressing the preforms together. Furthermore, the first and second tool components can be configured substantially similarly, wherein the first and second tool components are made of, for example, the same material and may have the same coating.

[0045] This type of hot-pressing apparatus enables the shaping of a product from a preform during the hot-pressing process, maintaining a short cycle time and producing preforms / products within a specified framework, meaning they have maximum residual moisture content and do not experience "clogging" during manufacturing. As described above, this is achieved by additionally introducing gas, a mixed gas, or ambient air through at least one second opening in the first tool component during the hot-pressing process while venting fluid (e.g., water vapor). This allows for pressure compensation in the channels of the first tool body and adjustment of boiling points in different chambers to achieve equilibrium. Furthermore, a larger volume of fluid (e.g., water vapor) can be discharged.

[0046] Not only the at least one first molding device, but also the at least one second molding device can be made of a material with good thermal conductivity, and which, in turn, is resistant to damage from fibers, pulp, and escaping water vapor, just like the first and second tool bodies. Metals and alloys are particularly suitable as materials. For example, the at least one first molding device and the at least one second molding device can be made of aluminum.

[0047] In a further embodiment, the second tool component may have a second temperature regulating device configured to regulate the temperature of the second tool body and the at least one second molding device. In addition to heating the first tool component, the second tool component can also be heated via the second temperature regulating device. Here, the first and second tool components can reach substantially the same or different temperatures. This allows for directional heating of the preform within the cavity. Furthermore, this takes into account, for example, the fact that the preform is initially placed on the first or second contact surface, which cools due to the liquid (water) contained in the preform. This may, for example, allow these contact surfaces to be heated more intensely, so that during hot pressing, when the first and second tool components are pressed against each other, substantially equal amounts of heat energy can be introduced to both sides of the preform within the cavity.

[0048] The first and / or second temperature control devices may include, for example, heating cylinders inserted into the first and / or second tool bodies. The configuration of the temperature control devices and the number of heating cylinders depend on the construction of the tool components (size, material / raw material), the number of molding devices, and their construction (size and volume).

[0049] In a further embodiment, the first temperature control device and / or the second temperature control device may also have other heating devices configured to heat the first tool body and / or the second tool body and the molding device disposed thereon.

[0050] In a further embodiment, the temperatures of the first and second tool components can be adjusted during operation of the hot pressing apparatus in a method of regulating the hot pressing apparatus with the hot pressing tool (which has the first and second tool components). For this purpose, values ​​detected during hot pressing can be considered, for example. Values ​​detected after and before the hot pressing process can also be used. Furthermore, predetermined or prepared values ​​and data of the components and materials involved in the process can also be used. These values ​​can be, for example, the temperature within the hot press tool, particularly the temperature within the cavity, and here the surface temperatures of the first and / or second contact surfaces, the pressure within the cavity, the pressure of the at least one first channel, the pressure of the at least one second channel, the pressure of the at least one third channel, and / or the pressure of at least one additional channel within the second tool body, the weight of the preform / finished product, the energy required to heat the first and / or second tool bodies, the temperature of the secondary flow of the transported gas or gas mixture (e.g., ambient air), the temperature of the transported gas or gas mixture or the temperature of the fluid discharged from the hot press tool, the composition of the slurry, the electrical conductivity of the preform / finished product, and / or reference values, where the reference values ​​refer to, for example, the core temperature of the tool body or a temperature below and very close to the contact surface within the cavity. The surface temperature on the contact surface is then derived using the reference values. Thus, for example, the dominant temperature of the contact surface within the tool body cavity at a distance of, for example, 5 mm below the surface is predetermined. Simultaneously, the actual surface temperature is measured using a separate measuring device. The corresponding surface temperature on the contact surface can be determined for multiple reference values ​​(temperatures within the tool body). This provides the possibility of deriving the dominant temperature on the surface of the contact surface during the hot pressing process via a thermal sensor installed below the contact surface within the tool body. Here, corresponding reference values ​​can also be predetermined before placing the wet preform onto the contact surface to account for the influence of these reference values ​​on the surface temperature.

[0051] In a further embodiment, the at least one second molding device has a third opening on the second contact surface of the preform to be accommodated, these third openings leading to a third channel in the second tool body, wherein the at least one third channel leads from the third opening to at least one third interface. This provides the possibility of draining fluid from the preform from both sides. For this purpose, in a further embodiment, a suction device can be connected, for example, via the third interface. A suction device similar to that used for the first interface can be used here. Furthermore, similar to the at least one second channel in the first tool body, an additional channel can be provided in the second tool body through which gas, mixed gas, or ambient air is delivered. This allows an "air cushion" to be formed on the second contact surface, because leaked fluid can always be drained, and the cavities facing the preform will not become blocked.

[0052] Sensor elements for temperature detection can be arranged on the surfaces of the first and / or second contact surfaces. In particular, multiple sensor elements can be arranged at different locations in the molding apparatus to detect the local dominant temperature in the cavity, thereby controlling, in further embodiments, the closing speed, cycle time, heating of the tool by a temperature control device, and the position of the valve, and possibly also the power of the exhaust device or the power of the conveying device for conveying gas or mixed gas side streams.

[0053] In a further embodiment, sensor elements for determining the surface temperature of the contact surface may be additionally or alternatively arranged below the surface. These sensor elements detect temperature reference values, which are also used as the corresponding, pre-determined surface temperatures on the contact surface. Here, the smaller the difference between the actual surface temperature and the reference temperature in the tool body that is lower than the surface temperature, the smaller the distance between the sensor elements and the surface. For example, the sensor elements for detecting temperature may be arranged a few millimeters below the surface, for example, in the range of 1 mm to 5 mm. The closer the sensor elements are to the surface, the faster the temperature change can be detected. This is particularly important when a damp preform is placed and when the fluid / water is expelled at the beginning of the hot pressing process, when the surface temperature of the contact surface is decreasing. When the distance between the sensor elements and the surface of the contact surface is large, even if the tool body has relatively high thermal conductivity, the sensor elements will lag, resulting in a relatively late detection of temperature changes.

[0054] In a further embodiment, at least one second opening may be formed in the contact area between the at least one first molding device and the at least one second molding device. For this purpose, corresponding contact areas of the at least one first molding device and the at least one second molding device have partial sections, for example, recesses, which together form an opening when the first and second molding devices are in a connected state. This opening is partially formed by the area of ​​the at least one first molding device surrounding the opening, and partially by the area of ​​the at least one second molding device surrounding the opening. In a still further embodiment, the at least one second opening may also be formed by a recess in the connection area of ​​the at least one first molding device or the connection area of ​​the at least one second molding device.

[0055] Furthermore, the second opening may also be arranged below the connection area of ​​at least one first molding device and / or at least one second molding device. This second opening may also extend around the first molding device and / or the second molding device at regular or irregular intervals.

[0056] Furthermore, the aforementioned task also includes a method for hot-pressing a preform made of a fibrous material using a hot-pressing apparatus according to any one of the above embodiments, wherein a first tool component has a first tool body and at least one first molding device, and a second tool component has a second tool body and at least one second molding device complementary to the at least one first molding device, the method comprising the following steps:

[0057] - Provide at least one preform made of a fiber-containing material.

[0058] - Heating at least the first tool body and the at least one first molding device via at least one first temperature control device.

[0059] - Place the at least one preform onto the first contact surface of the at least one first molding device.

[0060] - The second tooling component is moved relative to the second tooling component, wherein the at least one preform abuts against the second contact surface of the at least one second molding device.

[0061] - Press the first tool component and the second tool component together until the first contact surface and the second contact surface form at least one closed cavity.

[0062] The residual humidity evaporated from the at least one first preform due to the heat input generated by the first temperature control device and the pressure generated by the mutual pressing of the first tool component and the second tool component is discharged through at least the first opening, the at least one first channel and the first interface. During the discharge of the evaporated residual humidity, the introduction of a gas or mixed gas having a different water saturation relative to the discharged water vapor is completed through at least one second opening that is separately provided from the at least one first interface and fluidly connected to the first opening of the at least one first molding device.

[0063] At least one second opening, fluidly connected to the first opening of the at least one first molding device, allows for the simultaneous intake of gas or a mixture of gases (e.g., ambient air) by the suction device during the removal of residual moisture content from evaporation. Depending on the flow rate and water saturation of the secondary stream introduced in this manner, sufficient water vapor can always be adequately removed without causing a collapse of the environmental parameters required for hot pressing when adjusting the thermodynamic conditions in the consistent chamber. Such a collapse could occur, for example, when the temperature in the chamber drops sharply and / or the pressure in the chamber changes drastically. Therefore, the method optimizes production time or cycle time for hot pressing preforms from relatively moist slurry, where the boiling points in each chamber can be uniformly adjusted while simultaneously improving water vapor removal, as described below for the tool components of the hot pressing tool and for the hot pressing device.

[0064] In the method, the second tooling component and the at least one second molding device may also be temperature regulated, wherein uniform heating or differentiated heating for this purpose can be achieved via the first contact surface and the second contact surface.

[0065] In a further embodiment, the method also regulates the hot pressing process, wherein the cycle time, the pressure generated by the respective presses when pressing the first and second tooling components, the amount of fluid drawn in (e.g., by adjusting the suction power), and perhaps also the position of the valve at the passage for drawing in gas or a mixture of gases (e.g., ambient air), and the closing speed (i.e., the speed at which the first and second tooling components move relative to each other) are all regulated by a control system. For this purpose, the control system is connected to a device capable of changing or influencing the aforementioned settings and parameters.

[0066] Temperatures in tool components can be detected and determined using sensor elements (temperature measuring devices or tools for detecting surface temperature) that can be arranged as described above, wherein closing speed, cycle time, suction power and / or valve position can be adjusted by a control system based on these temperatures.

[0067] In a further embodiment, the gas or gas mixture may be derived from the surrounding environment of the at least one tool component or provided by a feeding device, wherein the temperature and / or pressure of the gas or gas mixture delivered via the at least one second opening is regulated by the feeding device in at least one cavity.

[0068] The feeding device may, for example, have a compressor that brings in ambient air, a gas (e.g., oxygen), or another mixture of gases at a higher pressure than ambient air. What may occur here is that the low pressure used to draw water vapor away from the chamber via the suction device cannot be maintained at the level provided by the suction device. It is important here to maintain the suction effect of water vapor removal at least in a specified direction, or, if necessary, to provide support through overpressure of the supplied gas or mixed gas offflow ("blowing" water vapor towards the suction device).

[0069] In a further embodiment, the residual moisture content from evaporation can be drawn in via the at least one first interface at an absolute pressure of 0.1 to 0.7 bar, and / or the gas or gas mixture can be delivered via the at least one second opening at an absolute pressure of 0.5 to 5 bar, preferably 1 to 1.5 bar.

[0070] The embodiments described above for tool components and hot pressing devices are also applicable to different methods.

[0071] Further features, implementation methods and advantages will become apparent from the following description of the embodiments with reference to the accompanying drawings. Attached Figure Description

[0072] The diagram shows:

[0073] Figure 1 This is a schematic diagram of a fiber forming machine used to produce products made of fibrous materials;

[0074] Figure 2 This is a schematic diagram of a molding station with a hot pressing device used to hot press preforms with hot pressing tools to produce products made of fibrous materials.

[0075] Figure 3 This is a perspective view of a tool component of a hot press tool;

[0076] Figure 4 yes Figure 3 First schematic cross-sectional view of the tool component shown;

[0077] Figure 5 yes Figure 3 The second schematic cross-sectional view of the tool component shown;

[0078] Figure 6It is a method for producing products made of fibrous materials; and

[0079] Figure 7a , Figure 7b This is a variety of illustrations of a finished bowl made of fibrous material, produced according to the manufacturing process described in this article. Detailed Implementation

[0080] The technical guidance described herein is illustrated below with reference to the accompanying drawings. The same reference numerals are used for the same components, parts, and processes in the description of the drawings. Components, parts, and processes that are not essential to the technical guidance disclosed herein or that can be deduced by a person skilled in the art will not be repeated. Unless otherwise explicitly stated, features listed in the singular also include the plural form, especially when “a” or “an” is used in the text.

[0081] The accompanying drawings illustrate various embodiments of the tool components 640, 690, the hot pressing device 610 and the corresponding forming station 600, the fiber forming machine 1000, and the method 2000 for operating the fiber forming machine (particularly for hot pressing fiber molded articles). The embodiments shown herein do not constitute a limitation on the improvement and modification of the described embodiments.

[0082] Figure 1 A schematic diagram of a fiber forming machine 1000 for producing products made from fibrous materials is shown. In the illustrated embodiment, the fibrous material for manufacturing the product is prepared by fiber processing equipment and supplied to the fiber forming machine 1000. This preparation and supply can be achieved, for example, via a supply conduit, wherein liquid slurry is continuously or intermittently conveyed from the fiber processing equipment to a storage container or slurry tank 200 of the fiber forming machine 1000. Alternatively, the slurry can be prepared in the slurry tank 200 of the fiber forming machine 1000. For this purpose, water and fibrous material, and if necessary, additives, can be added to the slurry tank 200 via liquid conveying, and the slurry in the slurry tank 200 is processed by mixing the various components under heat input and by auxiliary tools (e.g., a mixer).

[0083] Pulp refers to a solution containing fibers, wherein the fiber content of this aqueous solution ranges from 0.5% to 10% by weight. It may also contain additives such as starch, chemical additives, and waxes. The fibers can be, for example, natural fibers, such as cellulose fibers, or fibers made from fiber-containing raw materials (such as waste paper).

[0084] The fiber processing equipment provides the possibility of producing large quantities of virgin pulp and supplies it to multiple fiber forming machines (1000).

[0085] For example, biodegradable cups, capsules, and bowls can be manufactured using a fiber forming machine 1000 (3000). Figure 7a , Figure 7b Plates and other molded parts and / or packaging components (e.g., as brackets / support structures for electronic devices). Because the raw material for the products is fiber pulp containing natural fibers, the products produced can be reused as raw materials for manufacturing such products or composted after use, as they are generally completely decomposable and do not contain any worrying, environmentally harmful substances.

[0086] Figure 1 The fiber forming machine 1000 shown has a frame 100 that can be enclosed by a cladding. The cladding may have transparent sidewalls through which the workstations and work units of the fiber forming machine can be viewed, allowing for visual monitoring of the production process. The cladding serves to protect the machine from damage caused by movable parts and sometimes heated sections of the fiber forming machine 1000, as well as from the fiber material from the pulp and the pulp itself, which may "splash" during production. The supply unit 300 of the fiber forming machine 1000 is accessible through a door. Figure 1 As shown on the longitudinal side, the cladding may have sliding or rotating doors, thereby enabling maintenance of all workstations of the fiber forming machine 100.

[0087] The supply unit 300 of the fiber forming machine 1000 includes, for example, ports for supplying media (e.g., water, pulp, compressed air, gas, etc.) and energy (power supply), a central control unit 310, at least one suction / exhaust device 320, conduit systems for different media, pumps, valves, conduits, sensors, measuring devices, bus systems, etc., and ports for bidirectional communication via wired and / or wireless data connections. Alternatively, a data connection can be formed via fiber optic cable. The data connection can be formed, for example, between the control unit 310 and a central control system for multiple fiber forming machines 1000, connecting fiber processing equipment, service points, and / or other facilities. Control of the fiber forming machine 1000 can also be accomplished via indirect data connections through mobile devices (e.g., smartphones, tablets, or the like).

[0088] The control unit 310 communicates bidirectionally with the HMI panel 700 via a bus system or data connection. The HMI panel 700 has a display showing the operating data and status of optional components of the fiber forming machine 1000 or the entire fiber forming machine 1000. This display can be configured as a touch screen, allowing the operator of the fiber forming machine 1000 to manually complete settings. Alternatively or additionally, more input tools, such as keyboards, joysticks, and keypads, can be designed on the HMI panel 700 for operator input. This allows for changes to settings and influences the operation of the fiber forming machine 1000.

[0089] The fiber forming machine 1000 includes a robot 500. The robot 500 is designed as a so-called six-axis robot, enabling it to pick up, rotate, and move parts in any spatial direction within its radius of operation. Alternatively to the robot 500 shown in the figure, other processing devices can be designed, configured to accommodate, rotate, or rotate products and move them in different spatial directions. Furthermore, such processing devices can be configured in different ways, wherein the arrangement of the corresponding workstations of the fiber forming machine 1000 may differ from the illustrated embodiment.

[0090] A suction tool is arranged on the robot 500. In the illustrated embodiment, the suction tool has, for example, a suction mold manufactured in reverse to the shape of the product to be molded, such as... Figure 7a , Figure 7b The bowl 3000 is shown in the diagram. These suction molds can, for example, have a mesh-like structure on which fibers from the pulp are deposited. These suction molds also have openings through which the pulp can be drawn by vacuum when the suction tool is in the pulp tank 200 and the suction mold is at least partially immersed in the aqueous fiber solution (pulp). When the suction tool is in the pulp tank 200 and in the pulp, a vacuum or low pressure can be provided via the exhaust device 320 for drawing the fibers. For this purpose, the fiber forming machine 1000 arranges corresponding tools near the supply unit 300. The suction tool has a conduit for providing vacuum / low pressure, extending from the exhaust device 320 at the supply unit 300 to the suction tool, and has an opening in the suction mold. Valves are arranged in the conduit, which can be driven via the control unit 310 to regulate the drawing of fibers. This can also be accomplished by the exhaust device 320 not by drawing but by “blowing”, for which the exhaust device 320 is switched to another operating mode according to its design.

[0091] When manufacturing products from fibrous materials, a suction tool is immersed in the pulp, and low pressure / vacuum is applied at the opening of the suction mold, thereby drawing the fibers from the pulp and adhering them to the suction mold of the suction tool. Subsequently, a robot 500 moves the suction tool, along with the fibers attached to the suction mold (which still have a relatively high moisture content, e.g., more than 80% by weight), to the pre-compression station 400 of the fiber forming machine 1000. During this process, the low pressure on the suction mold is maintained. The pre-compression station 400 has a pre-compression tool with a pre-compression mold. The pre-compression mold can, for example, be configured to conform to the shape of the product to be molded and has dimensions appropriate to the product design in order to accommodate the fibers attached to the suction mold.

[0092] During product manufacturing, a suction tool with fibers attached to a suction mold is moved toward a pre-compression station 400 such that the fibers are pressed into the pre-compression mold. Here, the fibers on the suction mold are pressed together, thereby creating a stronger bond between the fibers. Furthermore, the moisture content of the resulting preform decreases, so that the preform formed after pre-compression has a moisture content of, for example, 60% by weight.

[0093] During precompression, liquid or slurry can be sucked away and returned via a suction device and / or other openings in the precompression mold. Liquid or slurry exiting the precompression station 400 during suction and / or during precompression can be returned to the slurry tank 200.

[0094] After pre-pressing in pre-pressing station 400, the preform produced in this manner is moved by robot 500 on a suction tool to forming station 600. For this purpose, a vacuum is maintained on the suction tool to keep the preform on or within the suction mold. The preform is conveyed via the suction tool to a first tool body 642 below, which can exit from the hot press 610 along the production line. If the tool 642 is in its exit position, the suction tool moves toward the tool body 642 such that the preform can be placed onto the first molding device 670 of the tool body 642. Subsequently, overpressure is created through an opening in the suction tool, causing the preform to be actively removed from the suction mold, or the extraction process to stop, allowing the preform to remain on the first molding device 670 of the first tool body 642 due to gravity. By providing overpressure at the opening of the suction mold, the pre-pressed preform resting against / adhering to the suction mold can be released and discharged.

[0095] After this, the suction tool is removed by robot 500 and immersed in the pulp tank 200 to extract more fibers to produce fiber-containing products.

[0096] Then, pressing is performed in the forming station 600 under heat input. After this hot pressing process, the first tool body 642 and the second tool body 692 move away from each other, and the upper second tool body 692 moves along the fiber forming machine 1000 in the production direction, wherein, after hot pressing, the finished product is sucked up by the upper second tool body 692 and thus retained in the second molding device 694. Therefore, the finished product is taken away from the forming station 600 and, after processing by the second tool body 692, is placed on the conveyor belt of the conveyor 800. After placement, the suction operation of the second tool body 692 ends, and the product remains on the conveyor belt. The upper second tool body 692 moves back to the forming station 600, and another hot pressing process can be performed.

[0097] The molding station 600 includes a hot press device 610. In the hot press device 610, the preform is extruded under heat into a finished product made of fibrous material. One possible embodiment of the molding station 600 is as follows: Figure 2 As shown in the image.

[0098] The fiber forming machine 1000 also includes a conveyor 800 with a conveyor belt. After final forming and hot pressing are completed at the forming station 600, the finished product made of the fiber-containing material can be placed on the conveyor belt and carried out from the fiber forming machine 1000. In a further embodiment, further processing, such as printing, filling, and / or stacking, can be performed after the product is placed on the conveyor belt of the conveyor 800. Stacking can be done, for example, by an additional robot or another device. Such a device may, for example, have at least one gripper 910 that grips the product placed on the conveyor belt and stacks it in a crate or the like. The at least one gripper 910 may work in conjunction with an optical device (such as a camera) to detect the position and orientation of the product, wherein the image captured by the camera is evaluated by software, and then the software outputs control commands to the at least one gripper based on the evaluated image.

[0099] Furthermore, the fiber forming machine 1000 has a stacking device 900 arranged downstream of the forming station 600 in the production line direction. In the illustrated embodiment, the stacking device 900 has two gripper devices arranged in a front-to-back manner, each gripper device having a gripper 910. The grippers 910 can be used to grip and, for example, stack the individual bowls 3000 after hot pressing. Figure 1 As shown in the diagram, a camera 810 is positioned in front of the stacking device 900 to detect the position and orientation of bowls 3000 arranged on the conveyor belt of the conveyor 800. The captured images are evaluated by a controller that generates control commands for the gripper 910 to pick up the bowls 3000.

[0100] In a further embodiment, the fiber forming machine 1000 may have a crane for replacing the first tool body 642 and the second tool body 692, for retrofitting the fiber forming machine 1000 to produce other products, or for maintaining the tool body 642 and / or the tool body 992.

[0101] Figure 2 A schematic diagram of a molding station 600 with a hot pressing device 610 is shown, which is used to hot press preforms with a hot pressing tool to produce products made of fibrous materials.

[0102] Figure 2 A molding station 600 in the open state is shown. The molding station 600, having a hot press 610, has a base 620 with a tool table 622. A first tool component 640 is arranged on the tool table 622. The first tool component 640 has a first tool body 642 arranged linearly on the tool table 622 below it. The first tool body 642 can move relative to the tool table 622 in a drawing direction. A guide rail system or other device is designed for the linearly movable first tool body 642. Additionally, a drive is designed to perform the movement of the first tool body 642. This drive is adjusted by a control unit 310 according to a control signal. A plurality of molding devices 670 are arranged on the upper side of the first tool body 642, and they are configured in the opposite shape to the product to be molded. (Refer to below...) Figure 3 and 4 The structural design of the molding device is described in detail.

[0103] The molding station 600 has a second tool component 690 with a second tool body 692. The upper second tool body 692 has a second molding device 696 on its bottom side, which is configured to conform to the shape of the product to be molded. When the first tool component 640 and the second tool component 690 move and press against each other, cavities are generated between the contact surfaces 676 and 696 of the first molding device 670 and the second molding device 694, respectively, whose size and shape conform to the size and shape of the product to be manufactured.

[0104] The upper tool body 692 is linearly movable on the upper tool table 628, thereby allowing the upper tool body 692 to be moved in the opposite direction to the first tool body 642 via a guide rail system or similar device and a matching drive member at the end of a hot pressing process, so as to place the finished product onto the conveyor belt of the conveyor 800. The drive member is controlled by the control unit 310.

[0105] The upper tool table 628 can be moved in the direction of movement 602 via a press (e.g., a toggle press 630) via a guide rod 626. Alternatively, in another embodiment, the press is implemented by a linearly movable pressure device (also indicated by reference numeral 630). This pressure device can be pneumatically, hydraulically, and / or electrically driven via corresponding means, and performs relative movement between the first tool part 640 and the second tool part 690. The toggle press 630 is arranged on the support yoke 632 of the forming station 600. According to the control unit 310d, the second tool part 690 is moved downward toward the first tool part 640 via the toggle press 630, wherein the second tool body 692 with the second molding device 694 is guided above the upper tool table 628 and the guide rod 626.

[0106] In the illustrated embodiment, port 624 is used to provide control commands, supply power, provide a medium (e.g., compressed air) and discharge a medium (e.g., drawn fluid, air, water, etc.).

[0107] The first tool body 642, the first molding device 670, and the second tool body 692 with the second molding device 694 are made, in particular, of a material with very good thermal conductivity. Preferably, metal is used for this purpose. In the illustrated embodiment, the first tool body 642, the first molding device 670, the second tool body 692, and the second molding device 694 are made of aluminum.

[0108] Temperature control devices are housed in the first tool body 642 and the second tool body 692, providing heating for the tool bodies 642 and 692, as well as the molding devices 670 and 694. These temperature control devices are driven by control signals from the control unit 310. For example, the temperature control device is a heating cylinder 660. The heating cylinder 660 generates heat by applying voltage. Therefore, the heating of the tool parts 640 and 690 can be easily adjusted. Other temperature control devices may be used in other embodiments.

[0109] Figure 3A schematic partial cross-sectional view of the tool component 640 of the hot press tool is shown in perspective. The first tool component 640 has a plate 644 on its upper side, on which a molding device 670 for heating the bowl 3000 can be connected via fasteners (such as screws 662 and corresponding openings in the plate 644) to the first tool body 642. The first molding device 670 has a socket 672 with a corresponding opening for fastening to the first tool body 642, wherein the socket 672 is not used for molding the bowl 3000. This allows the first molding device 670 to be replaced, for example, to modify a fiber forming machine to produce other products, or to replace a contaminated or damaged first molding device 670 for maintenance.

[0110] On the bottom side, the first tool body 642 is formed into a first tool body 641 according to a guide rail system for repositioning the first tool body 642. For this purpose, a rack and pinion are further arranged on the first tool body 642, which mesh with the driven gear of a drive provided on the tool table 622. By rotating the gear via the drive device, the first tool body 642 can be fed to reposition it.

[0111] In the illustrated embodiment, two first channels 646 extend substantially in the direction shown in the drawing within the first tool body 642. The first channels 646 are fluidly connected via a connecting unit 650 to a suction device (e.g., suction device 320), thereby allowing a vacuum to be created in the first channels 646 via a corresponding first interface and connecting unit 650. The first channels 646 in the first tool body 642 are also connected to a second channel 652, wherein the second channel 656 extends transversely to the first channels 646 and is oriented parallel to each other.

[0112] The second channel 652 has a second port 654 equipped with a valve 656. In this embodiment, the second port 654 constitutes a second opening through which ambient air is supplied, or in a further embodiment, a gas (e.g., oxygen) or another gas mixture is supplied. In a still further embodiment, the amount and pressure of the supplied gas or gas mixture can be regulated by a compressor. Such a compressor may, for example, be arranged in the supply unit 300 and fluidly connected via port 624 to at least one of the second openings to provide a “sidestream” of gas or gas mixture during thermocompression.

[0113] In a further embodiment, the second opening is arranged on other surfaces of the first tool body 642. For example, one or more second openings can be arranged on the upper surface of the plate 644, on the bottom side opposite to the plate 644, or on other sidewalls, and with... Figure 3The sidewalls of the valve 656 shown are orthogonal or opposite to each other. For example, when the second opening is arranged on the upper surface of the plate 644, it is possible to design a relatively short second channel to achieve a small amount of cooling to the tool body 642, and thus to the molding apparatus 670. The second opening arranged on the upper surface of the plate 644 can be designed, in particular, between the first molding apparatus 670, because there may be localized areas where the most intense heating of the tool body 642 may occur during the operation of the hot press. Thus, heating of the gas or gas mixture supplied via the second opening can be achieved without causing the energy extracted from the tool body 642 for this purpose to locally drop the tool body 642 below the required temperature for heating the molding apparatus 670.

[0114] In a further embodiment, the supply unit 300 includes a heating device for heating the gas or gas mixture in the secondary stream, thereby allowing the secondary stream with a specified temperature to be introduced via the second opening. Since the water saturation of the secondary stream is crucial to its ability to discharge water vapor, in a further embodiment, the supply unit 300 may also have a device for dehumidifying the gas or gas mixture in the secondary stream before it is conveyed via at least one second opening. This dehumidification device is particularly necessary when, for example, ambient air is introduced into the secondary air stream, and the ambient air already has a relatively high water saturation or humidity content.

[0115] In a further embodiment, a water vapor / gas stream with a relatively high temperature (>90°C) that is being drawn in or otherwise discharged can be guided via a heat exchanger that transfers heat to the drawn in or otherwise supplied secondary stream, which is introduced via a second opening or valve 656. This utilizes the energy of the discharged fluid from the cavity to heat the secondary stream. This prevents or reduces the possibility of tool parts 640, 690 being cooled via the secondary stream. Furthermore, warmer air, for example, has a higher water vapor absorption capacity due to its lower saturation. This further improves water vapor discharge.

[0116] The second channel 652 is fluidly connected to the surrounding environment via valve 656, thereby allowing the intake of, for example, a gas mixture (e.g., ambient air) or gas. Valve 656 can be actuated via control unit 310, thus allowing adjustment of the amount of gas mixture or gas that can be drawn in. At the end opposite to valve 656, the second channel 652 is closed. In a further embodiment, the second channel 652 does not have valve 656, thereby permanently creating a connection to the surrounding environment or to a device for supplying gas or gas mixture via a corresponding second opening, and the gas mixture or gas is drawn into the second channel 646 in conjunction with the provision of a vacuum or low pressure.

[0117] Starting from the second channel 652, a vertical channel segment 653 extends through the plate 644 and is opposite to a matching opening in the socket 672 on the underside of the first molding device 670. The first molding device 670 has a molding channel 648 leading to a plurality of openings 678 on the surface of the mold 674 formed by the first molding device 67. The surfaces of these molds 674 here form a first contact surface 676 for receiving a preform made of a fibrous material.

[0118] The molds 674 shown are used to manufacture a bowl 3000 as a finished product from a preform. For this purpose, the molds 674 have a flat surface for forming the bottom 3010 of the bowl 3000. A surrounding sidewall 3020 extends from the bottom 3010 and is formed by the inclined sides of the molds 674. In the illustrated embodiment, the finished bowl 3000 ( Figure 7a It has a generally circular bottom surface and a surrounding, steep side surface, with an edge 3030 at the upper end opposite to the bottom 3010, which is formed on the lower ring of the mold 674 extending around the inclined side surface.

[0119] Parallel to the second channel 652, a heating cylinder 660 extends through a first tool body 642, which is powered via a connection unit 650 and can be driven via a control unit 310. In the illustrated embodiment, the first tool body 642 is heated to, for example, 250°C via the heating cylinder 660. In a further embodiment, the first tool body 642 can be heated, for example, in a temperature range of 150°C to 300°C. The second tool body 692 can also be heated via the heating cylinder 660 or other temperature control devices, particularly within the same temperature range as the first tool body 642. In the illustrated embodiment, for example, the first tool body 642 and the second tool body 692 are heated to substantially the same temperature level.

[0120] exist Figure 3A first temperature sensor 680 is shown, arranged in the connection point area between the sockets 672 of the respective first molding devices 670. The first temperature sensor 680 can be designed and operated to determine the temperature during hot pressing only for a specific time period or continuously during the production process. The first temperature sensor 680 is connected to the control unit 310 via corresponding wires. In a further embodiment, a wireless bidirectional communication segment may also exist between the temperature sensors 680, 681, 682 and the control unit 310. For the operation of the temperature sensors, the required energy can be provided, for example, via an energy storage device, which is then connected to the respective temperature sensor. Therefore, the control unit 310 can use the detected temperature values ​​to adjust the heating of the first tooling part 640 and the second tooling part 690, as well as the cycle time of hot pressing, particularly the duration and approach speed of the molding device 600.

[0121] exist Figure 3 Another embodiment is shown, which has a second opening configured as a groove 658. The groove 658 is located in the contact area of ​​the molding device 670, which serves as the corresponding contact area of ​​the second molding device 694. When the hot pressing device 610 is in the closed state, the first molding device 670 and the second molding device 694 are located on opposing surfaces of the contact area. A small second opening is thus formed in the region of the groove 658, through which a fluid connection to the first opening 678 is provided separately from the first interface. Ambient air can be drawn in via such a groove 658, for example, during hot pressing. Furthermore, another mixed gas or a single gas can be introduced into the cavity via this groove. In a further embodiment, the second molding device 694, with a corresponding structure, may also have a groove 658 or not. In a further embodiment, multiple grooves 658 may be designed to be distributed around the cavity.

[0122] Figure 4 It shows Figure 3 First schematic cross-sectional view of the first tool component 640. From Figure 4 As can be seen, the first channel 646, the second channel 652, and the molding channel 648 are connected via a vertical channel segment 653. The molding device 670 has an opening in its socket 672 at its bottom 672 opposite to the channel segment 653, thereby automatically holding the preform placed on the contact surface 676 by providing low pressure in the first channel 646. Furthermore, moisture exiting from the preform during hot pressing is drawn in through the first opening 678 in the first contact surface 676 and discharged through a channel in the first tool body 642. This reduces the moisture content of the preform and removes released moisture.

[0123] exist Figure 4Other temperature sensors for the intermediate molding device 670 are shown. These temperature sensors can be incorporated into all parts of the molding device 670. Furthermore, multiple such sensors can be arranged around the corresponding locations.

[0124] Therefore, the molding apparatus 670 has, for example, a second temperature sensor 681 in the edge region of the product to be manufactured. In addition, the molding apparatus 670 also has a third temperature sensor 682 in the bottom region of the product to be manufactured.

[0125] Temperature sensors 681 and 682 can be disposed directly on the surface of contact surface 676, for example. In a further embodiment, temperature sensors 681 and 682 can be disposed below the surface of contact surface 676. For example, these temperature sensors 681 and 682 are located 0.5 to 5 mm below the surface, so that on the one hand, these temperature sensors 681 and 682 will not affect the molding and hot pressing process due to their presence, while on the other hand, it still allows for relatively accurate temperature detection.

[0126] In a further embodiment, the measuring tips of temperature sensors 681 and 682 can be accommodated in an opening in the contact surface 676, wherein the structure and diameter of such opening substantially correspond to the first opening 678. Importantly, in such an embodiment, moisture content cannot be drawn through the opening into which the measuring tips are housed, and there is no fluid connection with the first opening 678 used for exhaust, thus preventing cooling of the measuring tips or the corresponding temperature sensors due to the exhaust water vapor flow and the accompanying intake of gas or mixed gas flow.

[0127] In embodiments where temperature sensors 681 and 682 are not directly arranged on the surface of contact surface 676, the temperature below the surface of contact surface 676 is measured by temperature sensors 680, 681, and 682 before use during regular operation, and the surface temperature of contact surface 676 is measured by other, non-fixed measuring devices. The difference is then calculated, taking into account factors such as cooling effects from moist preforms to determine the dominant temperature on the surface. The temperature below the surface of contact surface 676 detected by temperature sensors 680, 681, and 682 is then stored in a memory as a reference value for the actual dominant temperature on the surface. Control unit 310 accesses this memory during operation of the fiber forming machine 1000 to control and regulate its various units and workstations. Therefore, by using a reference value for surface temperature detection, the operation of forming station 600 can be completed without directly arranging temperature sensors on the surface of contact surface 676. Therefore, a significantly simpler temperature sensor can be used, and the cost of embedding temperature sensors 680, 681, and 682 is reduced compared to directly arranging them on the surface. For example, temperature sensors 680, 681, and 682 can be inserted into drilled holes in the first molding device 670. These drilled holes can then be sealed with a heat-resistant (high-temperature) material with poor thermal conductivity after the temperature sensors 680, 681, and 682 have been inserted.

[0128] In embodiments where temperature sensors 680, 681, and 682 are directly disposed on the surface of the first tooling component 640, the first molding device 670 may additionally have a (high) temperature resistant coating that extends at least over the entire contact surface (first contact surface 676) of at least the first molding device 670.

[0129] Figure 5 It shows Figure 3The figure shows a second schematic cross-sectional view of the first tool component 640, where the section passes through the second channel 652. This figure illustrates that, in this embodiment, the second channels 652 are parallel to each other and orthogonal to the first channel 646. In this embodiment, each second channel 652 has two connection areas with the first channel 646. In a further embodiment, the number of first channels 646 and connection areas may exceed two. In an even further embodiment, only one first channel 646 may be provided, so that each second channel 652 has only one connection area. In a further embodiment, one or more first channels 646 and one or more second channels 652 may not be "orthogonal" but extend relative to each other in other directions. In an even further embodiment, the first channels 646 and the second channels 652 may be "intertwined," wherein channels 646 and 652 alternately lie in a plane parallel to the plate 644.

[0130] The structural design of channels 646 and 652, especially the number and orientation of channels 646 and 652, is based on the volume of water vapor that must be discharged within a specified unit of time during the hot pressing process. Therefore, the arrangement of tool components 640 and 690 is based on maximizing the usable surface area provided by plate 644 for the molding apparatus. For example, a single channel of the first molding apparatus 670 may have a smaller diameter than a common channel section slightly in front of the connecting unit 650, because the volume of water vapor discharged per unit of time is greater than the volume of water vapor in each channel of the first molding apparatus 670. At least one common channel may have a continuously increasing or gradually increasing diameter in sections. Furthermore, in a further embodiment, the channels may also have corresponding radii and curvatures to facilitate the convenient outflow and discharge of water vapor.

[0131] exist Figures 3 to 5 In the embodiment of the tool body 642 shown, the first channel 646 has a larger diameter than the second channel 652, wherein the diameter of the second channel 652 is determined in particular by the cross-section required to prevent short-term blockage of the first channel 646 due to the localized generation of large volumes of water vapor. The diameters of channels 646 and 652 are at their maximum dimensions, thus preventing cooling of the tool body 642 due to the intake of mixed gases or gases, the temperature of which (especially when accompanied by ambient air) is generally lower than the temperature of the intake water vapor and the tool body 642.

[0132] In the illustrated embodiment, the second tool component 690 also includes a heating cylinder to regulate the temperature of the second tool body 692 and the associated second molding device 694. The second tool body 692 also includes a suction device, wherein, in different embodiments, this suction either does not remove water vapor generated during the hot pressing of the preform, or performs suction of the generated water vapor (additionally, ambient air) in a manner similar to that described for the first tool component 640. In another embodiment, suction is typically performed after hot pressing via corresponding openings in the second mold body 692 and the second molding device 694 to hold the finished product in the second molding device 694 and place it onto the conveyor belt of the conveyor 800 after the second tool body 692 has moved.

[0133] The construction of the second tool body 692 can generally differ from that of the first tool body 642 by only minor, inconsequential differences. Therefore, the second tool body 692 has a corresponding device connected to the second molding device 694, which has a mating construction with the first molding device 670 to form cavities between the first contact surface 676 of the first molding device 670 and the second contact surface 696 of the second molding device 694 in a compressed state. These cavities are closed when the first tool body 642 and the second tool body 692 are pressed together, so that no slurry or water vapor can escape except through the first opening 678 in the first contact surface 676. Since the suction is performed via the first interface, the flow direction of water vapor is defined, thereby preventing water vapor from escaping through the second opening.

[0134] In a further embodiment, the structural design of the first molding device 670 and the complementary structural design of the second molding device 694 can also be exactly the opposite of the embodiment shown in the figure. In this case, the suction tool with the suction mold and the pre-pressing station 400 with the pre-pressing mold must also be adjusted accordingly. Therefore, when the modified tool is used to produce other products, the suction tool, the pre-pressing tool, and the first and second molding devices 670 and 694 must be replaced.

[0135] In a further embodiment, the first and second tool bodies 642 and 692 may have integrated molding devices 670 and 694, which are fixedly connected to the first tool body 644 or the second tool body 692 and are configured, for example, as inseparable components.

[0136] As already described at the beginning, designing the hot pressing process is challenging when producing products from fibrous materials, especially when the moisture content of the preform to be hot-pressed is relatively high, because different temperature levels may exist in the cavity formed between the first contact surface 676 and the second contact surface 696. Furthermore, different pressure conditions can also lead to "clogging" and other problems mentioned at the beginning.

[0137] The design of the first tool body 642 described herein has at least one additional second channel 652 or at least one second opening through which a mixed gas or gas is drawn in conjunction with the water vapor formed during hot pressing. This design provides another possibility for solving the problem mentioned at the beginning because the temperature in the cavity is uniformly adjusted and sufficient volume is provided for the discharge of the generated water vapor, even if the locally generated water vapor reaches its peak in a short period of time.

[0138] By closing the hot press 610 in stages according to the current moisture content of the preform, the second tooling component 690 is pressed against the first tooling component 640 under force via the toggle press 630 or another pressure device. In other embodiments, this allows for targeted control of the amount of excess moisture exiting the preform, enabling effective evaporation at the heated contact surface 676 of the first molding device 670 and the contact surface 696 of the second molding device 694. This process can be achieved by monitoring the surface temperature or a reference value at the contact surfaces 676 and / or 696. This prevents excessive drop in surface temperature at the contact surfaces 676 and 696. The closing motion, especially the closing speed—the speed at which the second tooling component 690 moves toward the first tooling component 640—can be adjusted in stages for this purpose. Therefore, instead of the toggle press 630, a linear press device can be provided, allowing for precise, staged movement of the second tooling component 690. The closing motion and closing speed are regulated by the control unit 310.

[0139] The hot pressing process is carried out based on the composition of the pulp and the moisture content of the preform (consisting of a filter cake made of fibrous material). For the hot pressing process described herein, the residual moisture content after pre-pressing is crucial. The residual moisture content is in the range of 50% to 70% by gravity in the upstream processing steps using, for example, a silica gel pre-pressing body under pressure. Preferably, an attempt is made to keep the moisture content as low as possible through the pre-pressing process. During pre-pressing, the moisture content (water) is typically forced out mechanically from the adsorbed preform. Therefore, no evaporation occurs in this process.

[0140] The moisture content stored in the preform exists both between the fibers and as water bound within the fibers. The former can be mechanically extruded from the fiber weave, while the water bound within the fibers must be evaporated or vaporized.

[0141] In known slurry compositions, a specified residual moisture content in the preform can be achieved by specifying the absorption time in the slurry tank, the pressure during preloading, and the duration of preloading. The residual moisture content can also be determined for a given number of preforms using specified parameters. The preforms with the specified residual moisture content are then transferred, for example, to or placed on the lower half of the first tooling component 640. Here, the dimensional differences between the preloading tooling component and the hot-pressing tooling component due to varying thermal expansion must be considered for the preforms.

[0142] During transfer and transport to the hot pressing unit 610, the preform is actively held in position via the first opening 678. Subsequently, the first tooling component 640 and the second tooling component 690 close until they reach a holding position just above the contact point between the second molding device 694 and the preform. To avoid improper adhesion to the contact surface 696, they may pause there briefly, or the closing speed may decrease from this switching position. During linear closure, the closing force increases due to the proximity of the first tooling component 640, the second tooling component 690, and the intermediate preform. Water between the fiber bundles is thus mechanically squeezed out and evaporates on the hot surfaces of the contact surfaces 676 and 696 of the cavity. The amount of water produced during closure varies depending on the topology of the product and the residual moisture content after pre-pressing.

[0143] As excess water evaporates and periodically absorbs heat from the surfaces of contact surfaces 676 and 696, the surface temperature of the cavity drops sharply, and the excess water is converted into water vapor from its boiling point through energy input. The two tool components 640 and 690, equipped with molding devices 670 and 694, form a quasi-enclosed space during this process, in which the generated steam is systematically discharged through openings 678 and channels 646 and 652 in the tool bodies 642 and 692.

[0144] By controlling the ventilation of the tool bodies 642 and 692, instead of simply exhausting or drawing in steam, and in other embodiments combining this with controlled steam generation at a controlled closing speed, blockages are prevented, allowing the hot pressing process itself to proceed more stably and in a more balanced manner.

[0145] To achieve the physical limits of the hot pressing process and thus the fastest possible cycle time, it is essential to ensure maximum utilization of thermal energy. Here, the optimal cycle time is achieved when the direct surface temperature of the contact surfaces 676 and 696 of the cavity drops to the typical boiling point of the liquid contained in the preform. With ambient air ventilation, the boiling point is 100°C at normal atmospheric pressure, and no significant pressure increase occurs in the components of the hot press 610. By controlling the closure of the hot press, it is ensured that the amount of water carried out of the preform is only the same as the amount that can evaporate at the contact surfaces 676 and 696, without the surface temperature dropping below the boiling point of the carried-out liquid. This prevents excessive water from cooling the surface temperature below the boiling point, which would otherwise prevent steam generation until the energy stored in the molding apparatus 670 and 694 or the tool body 670 is released again to allow the water to evaporate again. In this case, cycle time would be wasted once the surface temperature drops below the boiling point. This can be avoided by adjusting the closing motion according to the surface temperature of the contact surfaces 676 and 696.

[0146] Furthermore, a typical shut-off rate can be defined that adapts not only to steam generation but also to optimal energy utilization. The scale for the relative shut-off rate, depending on the water volume, can be [mm / (s ml)] and varies within the range of e⁻³ (e.g., 2 × 10⁻³). -3 [mm / s ml]). The maximum possible absolute closing speed depends on the material and topology of the preform, where large surfaces with a large volume of water outflow in a short time are traversed more slowly in terms of absolute closing speed compared to inclined surfaces. In the embodiment shown in Figure 7, this means that the closing speed in the bottom 3010 region is slower than in the sidewall 3020 region, because there, less water is expelled from the preform material per stroke of the hot press 610.

[0147] In the illustrated hot press 610, the closing motion can be adjusted according to the outflow of water to adapt to the surface temperature of the contact surface 676. At the start of the hot pressing process, the contact surfaces 676 and 696 must therefore have a desired temperature, typically significantly higher than the boiling point of the outflowing liquid or water. In this embodiment, the contact surfaces 676 and 696 can be heated to 280°C. This allows the liquid contained in the preform to evaporate immediately upon closing the hot press 610, as the surface temperatures of the contact surfaces 676 and 696 in the cavity are sufficiently hot. The closing speed is based on the near-surface energy content of the contact surfaces 676 and 696 in the cavity. To determine the boiling point, known values ​​can be used, or the composition of the slurry can be monitored permanently or at fixed intervals, thereby determining the boiling point. The controller in the control unit 310 thus acquires the boiling point of the liquid and adjusts the closing of the hot press 610 based on the measured surface temperatures of the contact surfaces 676 and 696. Hot pressing can only be performed by the relative displacement of the first tool component 640 and the second tool component 690 when the contact surfaces 676 and 696 are within the allowable temperature range.

[0148] During the hot pressing process, after the second contact surface 696 contacts the preform placed on the first contact surface 676 and then moves further, moisture, especially water bound to the fibers, begins to be pressed out and evaporated. For the released water to evaporate, the contact surface 676 needs to have a correspondingly high temperature. The required temperature must be at least as high as the boiling point of the liquid.

[0149] The step-by-step closing of the hot-pressing device 610, while maintaining the position for a specified duration, can be permanently preset via the control unit 310. For this purpose, the surface temperature of the contact surface 676 must be monitored at least, as this surface temperature is crucial for the evaporation of the liquid. For example, if the surface temperature of the contact surface 676 drops drastically, the closing speed must be reduced or temporarily stopped until a rise in surface temperature is detected, or no further decrease is detected.

[0150] Of course, such a process can be predetermined for a specific product type. Values ​​determined from one or more test runs are then stored in a memory for controlling the hot pressing process, which is accessed by the control unit 310 that drives the hot pressing device 610. This can be monitored via a temperature sensor. If a significant deviation from the expected set value is detected, the control unit 310 can, for example, extend the cycle time or holding time.

[0151] In a further embodiment, when closing the hot pressing device 610, the second tool component 690 preferably has a linear stroke, wherein the displacement of the second tool component 690 can be directly controlled. This provides an advantage over methods driven via a cam disk or the like in reaching the holding position and providing closing force.

[0152] With all settings being equal, the temperature drop in the cavity remains constant relative to the initial temperature. This means that the higher the initial temperature, the faster the hot press device 610 closes, or more excess moisture will evaporate during the closing process.

[0153] The surface temperature of the cavity is largely independent of the heat supply via the heating cylinder 660, where reheating is supplied by the heat capacity of each cavity. Therefore, the cycle time, i.e., the time required for the preform to be hot-pressed into the finished product, depends primarily on the conductivity, shape, and heat capacity of the cavity, and thus adjusting the heating cylinder 660 has virtually no effect on the cycle time.

[0154] For this reason, in addition to providing gas or a gas mixture (e.g., ambient air) to expel released water vapor and regulate the temperature and pressure in the balancing chambers, the closure of the chambers is also related to the dominant temperatures on the surfaces of the first contact surface 676 and the second contact surface 696. Here, the boiling point of the slurry or liquid to be evaporated is considered. Typically, water vapor is generated in the chambers during hot pressing. In a further embodiment, the temperature in all chambers can be regulated to a substantially uniform temperature level by drawing in a gas mixture or a sidestream of gas during hot pressing. Furthermore, pressure balancing in the channels and chambers is achieved by drawing in a gas mixture or gas, which ultimately results in a substantially uniform temperature level in all chambers.

[0155] Finally, the hot-pressing device 610 can be closed based on the surface temperatures at contact surfaces 676 and 696, wherein the boiling point of the liquid contained in the preform and to be evaporated and discharged through the hot-pressing process plays a decisive role in the closing speed. Furthermore, in a further embodiment, the dominant pressure within each cavity can also be considered. In an embodiment connected to the surrounding environment to draw in ambient air, the boiling point is approximately 100°C when the pressure is approximately 1 bar. In an embodiment where ambient air is not drawn in, for example, a higher low pressure (e.g., 0.5 to 0.9 bar) may dominate in the cavity during hot pressing, so that the liquid released by compression can evaporate on the hot surface when the surface temperatures at contact surfaces 676 and 696 are lower.

[0156] In a further embodiment, the process of closing the hot press device 610 by the relative displacement of the first tooling component 640 and the second tooling component 690 is not continuous but stepwise. During this process, at least one holding position is established where, after the liquid is extruded from the preform, it evaporates on the hot surfaces of the contact surfaces 676 and 696. This results in the cooling of the surfaces of the contact surfaces 676 and 696. During the period when the second tooling component 690 remains in this holding position, sufficient time is allowed for the extruded water to evaporate without causing blockage within the cavity due to excessively rapid approach. Furthermore, the surfaces of the contact surfaces 676 and 696 can be at least partially reheated based on the heat capacity of the molding device.

[0157] In a further embodiment, multiple holding positions can be specified. The closing speed, as well as the duration and number of holding positions, can also be adjusted and changed during the hot pressing process based on detected values ​​(such as temperature).

[0158] In a further embodiment, persistent temperature measurements at contact surfaces 676 and / or 696 can be omitted, where, for example, predetermined cycle times, holding positions, and closing speeds are used during hot pressing. Since the surface temperatures at contact surfaces 676 and 696 depend primarily on the heat storage capacity and reheating of the material used, the cycle time is reduced based on, for example, the pause time between two consecutive hot pressing processes. The extent of the reduction in cycle time depends on the time span between the two consecutive hot pressing processes.

[0159] Figure 6 A method 2000 for producing products made of fibrous materials using the aforementioned components and a fiber forming machine 1000 is illustrated. In a further embodiment, individual steps may be omitted or performed in a different order in method 2000, provided that the objectives and advantages described herein are still achieved.

[0160] In the first method step 2010, a pulp in the form of an aqueous solution with a fiber content of 0.5% to 10% is supplied by the pulp tank 200 of the fiber forming machine 1000 or by a separate fiber processing device. This pulp either already exists in the pulp tank 200 or is transported to the pulp tank 200 by the fiber forming machine 1000 via suitable ports and conduits. For this purpose, the control unit 310 can adjust the supply of pulp from the remote fiber processing device according to the fill level of the pulp tank 200.

[0161] In method step 2040, the composition of the pulp can be continuously monitored or at predetermined time intervals via suitable sensors, and the boiling point of the pulp can be determined from this information. This information is sent to control unit 310, which stores it in memory and / or uses it to adjust the closing speed of the hot press 610, and to determine the number and duration of times the hot press 610 maintains its position when it approaches each other. The obtained information can also be used to determine the residual moisture content at different process workstations.

[0162] In method step 2012, the hot pressing tool is heated, wherein not only the first tool body 642 and the molding device 670 disposed thereon, but also the second tool body 692 and the molding device 694 disposed thereon are uniformly heated via a temperature control device (e.g., heating cylinder 660).

[0163] In method step 2042, the surface temperature of the contact surfaces 676 and / or 696 may be measured continuously or at fixed intervals by temperature sensors 680, 681, 682, or a reference value may be measured, or the surface temperature may be determined by control unit 310 based on a pre-detected temperature profile during hot pressing.

[0164] In step 2014, the suction tool is immersed in the slurry according to the product to be manufactured.

[0165] In method step 2016, the fibrous material is then drawn from the pulp by a suction device 320, which is adjusted accordingly by a control unit 310. Furthermore, a valve in at least one supply conduit between the suction device 320 and the suction mold of the suction tool can also be adjusted via the control unit 310.

[0166] In method step 2018, after the fiber is sucked up and the suction tool is moved to the pre-compression station 400, the pre-compression of the fiber material is completed in the suction mold and the pre-compression mold.

[0167] Subsequently, in method step 2020, the pre-pressed preform is brought into the first molding device 670 arranged on the first tool body 642 by the robot 500, wherein, for this purpose, the first tool body 641 is driven out of the molding station 600 in the manner described above. The pre-pressed preform is then placed onto the first molding device 670, wherein the low pressure used to maintain the preform is interrupted after placement. The preform is thus placed on the first contact surface 676 of the first molding device 670. Then, the first tool body 642, together with the preform placed on the first molding device 670, is moved back to the molding station 600.

[0168] In method step 2022, the hot pressing devices 610 and 696 are then closed according to the detected reference value, the measured temperature and / or the predetermined time and holding position, wherein the closure of the hot pressing device 610 is adjusted according to the boiling point of the liquid contained in the preform to adapt to the surface temperature of the contact surfaces 676 and 696.

[0169] In method step 2024, the liquid drawn out via the suction device 320 through the first opening 678, the second channel 652, and the first channel 646, and / or the water vapor formed by the evaporation of the drawn liquid at the heated contact surfaces 676 and 696. The suction operation is achieved during pressing by controlled movement of the second tool component 690 in the manner described above.

[0170] In method step 2026, during the extraction of water vapor, a mixed gas or gas (e.g., ambient air) is drawn in via a second opening (e.g., second channel 652), thereby ensuring a uniform temperature balance in the cavity based on the pressure balance in the channel and the cavity.

[0171] In a further embodiment, in method step 2028, the opening of valve 656 at the second channel 652 can be adjusted, wherein, based on the detected temperature, valve 656 adjusts the amount of mixed gas or gas delivered or drawn in, so as to achieve pressure balance and consistent temperature regulation in the cavity.

[0172] Alternatively, water vapor can be "blown out" through a second opening by providing a higher pressure secondary flow, in which the water vapor is carried away.

[0173] In method step 2030, after the preform is hot-pressed, i.e., exists as a finished product with a moisture content of, for example, 5% by weight, the hot-pressing tool is opened by the second tool component 690 being moved away from the first tool component 640. Furthermore, after opening, the displacement of the second tool body 692 is accomplished via a guide rail system and a corresponding drive component as described above, wherein the finished product remains in the upper tool.

[0174] After the upper tool body 692 is removed, the product is placed on the conveyor belt of the conveyor 800 in method step 2032, wherein the low pressure in the second molding device 694 is interrupted for this purpose.

[0175] Then the above process is repeated, wherein the production of the product from the fiber material is carried out in a manner that allows processing to be performed simultaneously at each workstation.

[0176] like Figure 6As shown, the control unit 310 can, in the process of manufacturing a product made of fibrous material, deduce the current processing state in each of the method steps 2012, 2018, 2024, 2026, and 2030 based on the detected and / or determined temperature, as well as the dominant pressure in the cavity, channel, and supply conduit, such as leading to the suction device 320, the weight of the preform and / or finished product, and / or the conductivity of the preform and / or finished product, and accordingly influence and change the method steps in terms of duration, speed, and, for example, temperature, to achieve the shortest possible cycle time during the hot pressing process without wasting resources and damaging the preform and / or product.

[0177] Figure 7a , Figure 7b Various figures are shown of finished bowls 3000 made of fibrous material produced according to the manufacturing process described herein. Such bowls 3000 have, for example, a residual moisture content of 1% to 7% by weight after hot pressing.

[0178] Figure 7a The image shows a perspective view of Bowl 3000. Figure 7b A cross-sectional view of a bowl 3000 is shown. The bowl 3000 has a bottom 3010 and a surrounding sidewall 3020 extending from the bottom 3010, the sidewall 3020 extending relatively steeply from the bottom 3011. At the upper end of the sidewall 3020, a surrounding edge 3030 extends, which is substantially parallel to the bottom 3010.

[0179] In the illustrated embodiment, the bowl 3000 has the same wall thickness at all locations, including the bottom 3010, sidewalls 3020, and edge 3030. The wall thickness is determined by the cavity when the first contact surface 676 and the second contact surface 696 are at minimum distance from each other during hot pressing.

[0180] List of reference numerals

[0181] 100 Frames

[0182] 200 puree pool

[0183] 300 supply units

[0184] 310 Control Unit

[0185] 320 Exhaust / Suction Device

[0186] 400 Preload Station

[0187] 500 robots

[0188] 600 molding station

[0189] 602 Direction of Motion

[0190] 610 Hot Press Device

[0191] 620 base frame

[0192] 622 Tool Table

[0193] Port 624

[0194] 626 guide rod

[0195] The workbench above 628

[0196] 630 elbow press

[0197] 632 Support Yoke

[0198] 640 First Tool Component

[0199] 642 First Tool Body

[0200] 644 board

[0201] 646 First Channel

[0202] 648 molding channel

[0203] 650 connection unit

[0204] 652 Second Channel

[0205] Section 653

[0206] 654 Second Interface

[0207] 656 valve

[0208] 658 slots

[0209] 660 heating cylinder

[0210] 662 screws

[0211] 670 molding device

[0212] 672 socket

[0213] 674 mold

[0214] 676 First Contact Surface

[0215] 678 First Opening

[0216] 680 First Temperature Sensor

[0217] 681 Second Temperature Sensor

[0218] 682 Third Temperature Sensor

[0219] 690 Second Tool Component

[0220] 692 Second Tool Body

[0221] 694 Second Molding Device

[0222] 696 Second Contact Surface

[0223] 700 HMI Panel

[0224] 800 Conveyor

[0225] 810 camera

[0226] 900 stacking device

[0227] 910 grabber

[0228] 1000 Fiber Molding Machine

[0229] 2000 methods

[0230] 2010 Methods and Steps

[0231] 2012 Methods and Steps

[0232] 2014 Methods and Steps

[0233] 2016 Methods and Steps

[0234] 2018 Methods and Steps

[0235] 2020 Methods and Steps

[0236] 2022 Methods and Steps

[0237] 2024 Methods and Steps

[0238] 2026 Methods and Steps

[0239] 2028 Method and Steps

[0240] 2030 Method and Steps

[0241] 2032 Method and Steps

[0242] 2040 Method Steps

[0243] 2042 Method Steps

[0244] 3000 bowls

[0245] 3010 bottom

[0246] 3020 sidewall

[0247] 3030 edge

Claims

1. A tool component for a hot pressing device (610), characterized in that, The tool component has a first tool body (642), wherein the first tool body (642) has at least one first molding device (670) on at least one side, having a first contact surface (676) for receiving a preform, wherein the first tool body (642) is made of a thermally conductive material and has a first temperature regulating device configured to regulate the temperature of the first tool body (642) and the at least one first molding device (670), wherein the at least one first molding device (670) has a first opening (678) on the first contact surface (676) for receiving the preform, the first opening leading to at least one first channel (646) in the first tool body (642), wherein the at least one first channel (646) leads from the first opening (678) to at least one first interface. At least one second opening is designed here, which provides a fluid connection to the first opening (678) of the at least one first molding device (670), separate from the at least one first interface. Among them, multiple first channels (646) have a common channel section, said common channel section having a diameter that gradually increases segmentally. The first contact surface (676) has a temperature sensor disposed below its surface, and the temperature sensor is configured such that the temperature below the surface of the first contact surface (676) measured before the tool component is regularly operated is stored as a reference value characterizing the surface temperature of the first contact surface (676).

2. The tool component according to claim 1, characterized in that, The at least one second opening is designed on the first tool body (642) and / or the at least one first molding device (670).

3. The tool component according to claim 1 or 2, characterized in that, The tool component has at least one second channel (652) which is fluidly connected to the at least one first channel (646) and the at least one second opening.

4. The tool component according to claim 1 or 2, characterized in that, The at least one second opening is connected to the surrounding environment, a gas storage device, or a device for providing gas or a gas mixture.

5. The tool component according to claim 1 or 2, characterized in that, The tool component has at least one adjusting element for adjusting the opening width of the at least one second opening.

6. The tool component according to claim 5, characterized in that, The at least one second opening and / or the at least one second channel (652) has at least one valve (656).

7. The tool component according to claim 3, characterized in that, The tool component has a plurality of second channels (652) extending within the first tool body (642).

8. The tool component according to claim 7, characterized in that, The second channel (652) extends parallel to each other.

9. A hot pressing device, characterized in that, The hot pressing device has a tool component according to any one of claims 1 to 8, the tool component comprising at least one first tool component (640) and at least one second tool component (690), wherein the second tool component (690) has a second tool body (692) made of a thermally conductive material, and the second tool body (692) has at least one second molding device (694) on at least one side, the second molding device being complementary to the at least one first molding device (670) and having a second contact surface (696) for accommodating a preform, such that when the first tool component (640) and the second tool component (690) are pressed against each other for hot pressing a preform, a cavity for accommodating a preform is formed between the first contact surface (676) of the at least one first molding device (670) of the first tool component (640) and the second contact surface (696) of the at least one second molding device (694) of the at least one second tool component (690).

10. The hot pressing device according to claim 9, characterized in that, The second tool component (690) has a second temperature control device configured to control the temperature of the second tool body (692) and the at least one second molding device (694).

11. The hot pressing apparatus according to claim 9 or 10, characterized in that, The at least one second molding device (694) has a third opening on a second contact surface (696) for receiving a preform, the openings leading to at least one third channel of the second tool body (692), wherein the at least one third channel leads from the third opening to at least one third interface.

12. The hot pressing apparatus according to claim 9 or 10, characterized in that, At least one second opening is formed in the contact area between the at least one first molding device (670) and the at least one second molding device (694).

13. A method for hot-pressing a preform made of a fibrous material using the hot-pressing apparatus (610) according to any one of claims 9 to 12, wherein, The first tool component (640) has a first tool body (642) and at least one first molding device (670), and the second tool component (690) has a second tool body (692) and at least one second molding device (694) complementary to the at least one first molding device (670), the method comprising the following steps: Provide at least one preform made of a fiber-containing material, At least the first tool body (642) and the at least one first molding device (670) are heated via at least one first temperature control device. At least one preform is placed on the first contact surface (676) of the at least one first molding device (670). The second tooling component (690) is moved relative to the first tooling component (640), wherein at least one preform abuts against the second contact surface (696) of the at least one second molding device (694). The first tool component (640) and the second tool component (690) are pressed together until the first contact surface (676) and the second contact surface (696) form at least one closed cavity. The residual humidity evaporated from at least one preform due to the heat input generated by the first temperature control device and the pressure generated by the mutual pressing of the first tool component (640) and the second tool component (690) is discharged via at least the first opening (678), the at least one first channel (646) and the first interface. During the discharge of the residual humidity, the introduction of a gas or mixed gas having a different water saturation relative to the discharged water vapor is completed via at least one second opening, which is separately provided from at least one interface and forms a fluid connection with the first opening of at least one first molding device (670).

14. The method according to claim 13, characterized in that, Gas or gas mixture is provided from the surrounding environment of the at least one tool component (640) or from the delivery device, wherein the temperature and / or pressure of the gas or gas mixture delivered via the at least one second opening is set in at least one cavity by the delivery device.

15. The method according to claim 13 or 14, characterized in that, The residual humidity from evaporation is drawn in at an absolute pressure of 0.1 to 0.9 bar via the at least one first interface, and / or these gases or gas mixtures are delivered at an absolute pressure of 0.5 to 1.5 bar via the at least one second opening.

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