Post-printing vacuum degassing device and method

Abstract

A degassing chamber for degassing material located on a workpiece includes a vacuum source, a vacuum reservoir in fluid communication with the vacuum source, an auxiliary chamber, a port valve, and a reservoir valve. The port valve is movable between an open position and a closed position, in which the workpiece is allowed to pass through the port valve between the exterior of the degassing chamber and the auxiliary chamber; in a closed position, the port valve is fluid-sealed. The reservoir valve is movable between an open position and a closed position, in which the auxiliary chamber and the vacuum reservoir are in fluid communication; in a closed position, the reservoir valve is fluid-sealed. The degassing chamber can be installed after a printing press on a production line and is particularly suitable for degassing silicone materials during the production of fuel cells.

Description

Technical Field

[0001] The present invention relates to a degassing chamber, a production line for producing workpieces, a printing machine for printing printing media onto workpieces, a method for degassing material printed onto workpieces, and a method for producing printed workpieces. Background Technology

[0002] Proton exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells (often abbreviated as "PEM fuel cells"), are expected to be a viable solution for the next generation of fuel cells. PEM fuel cells are known to typically consist of multiple layers or plates that can be assembled together to form a stack. Advantageously, suitable gaskets are used to surround each plate to form an edge seal. A suitable material for such gaskets is room temperature vulcanized ("RTV") silicone, which has adhesive properties and begins to cure from a wet material into a strong yet flexible, elastically deformable material once exposed to air.

[0003] To achieve high efficiency and streamlined production of PEM fuel cells, a method has been proposed for producing these gaskets by directly printing this RTV silicone material (or a substantially similar material) onto the PEM fuel cell plate using an industrial screen printing process. In this process, a printing press is used to apply the printing medium onto the workpiece by using a slanted squeegee or blade to apply the printing medium through holes or hole patterns in a printing screen (sometimes called a mask or stencil).

[0004] However, this method has the following problem: it has been found that the turbulent characteristics of the printing process inevitably introduce air bubbles into the moist gasket material. However, air bubbles in the gasket material are detrimental to operational reliability; therefore, ideally, the gasket material should not contain air bubbles. Summary of the Invention

[0005] The purpose of this invention is to reduce air bubbles present in printed gasket material to an operationally acceptable level.

[0006] According to the invention, this objective is achieved by providing a degassing chamber that can receive newly printed workpieces, the material printed on the workpieces still being wet, and using a vacuum reservoir to process these workpieces through at least a partial vacuum, thereby removing air bubbles from the printed material, wherein the vacuum reservoir maintains at least a partial vacuum whether the workpieces are introduced into or removed from the degassing chamber.

[0007] For the purposes of this invention, the term "wet" as used herein refers to a material that is not completely solidified but has a sufficiently low viscosity, such that air bubbles entrained in the material can freely pass through the material when subjected to vacuum treatment.

[0008] The applicant is unaware of any known process for vacuum degassing of newly printed articles, not just components of fuel cells made of any other workpiece (such as semiconductors or metal wafers, plates, etc.), nor of any known equipment suitable for such degassing.

[0009] According to a first aspect of the present invention, a degassing chamber for degassing material located on a workpiece is provided, comprising:

[0010] A vacuum source, which is used to generate at least a partial vacuum.

[0011] A vacuum reservoir, which is in fluid communication with the vacuum source, such that the at least partial vacuum is generated and maintained within the vacuum reservoir.

[0012] Auxiliary room,

[0013] A port valve movable between an open position and a closed position, wherein the open position allows a workpiece to pass through the port valve between the outside of the degassing chamber and the auxiliary chamber, and the closed position provides a fluid seal for the port valve.

[0014] A reservoir valve is movable between an open position and a closed position, wherein the auxiliary chamber and the vacuum reservoir are in fluid communication in the open position, and the reservoir valve is in fluid seal in the closed position.

[0015] According to a second aspect of the invention, a production line for producing workpieces is provided, comprising: a printing press and the aforementioned degassing chamber, the degassing chamber being located within the production line for receiving the workpiece after it has been printed by the printing press.

[0016] According to a third aspect of the present invention, a printing machine for printing a printing medium onto a workpiece is provided, comprising: a degassing chamber for degassing the printing medium after it has been printed onto the workpiece.

[0017] According to a fourth aspect of the present invention, a method for degassing material printed on a workpiece is provided, comprising the following steps.

[0018] Step i), providing a degassing chamber as described in the first aspect;

[0019] Step ii), using the vacuum source to generate and maintain at least a partial vacuum in the vacuum reservoir;

[0020] Step iii), insert the workpiece into the auxiliary chamber through the port valve;

[0021] Step iv), close the port valve;

[0022] Step v), opening the reservoir valve to increase the vacuum in the auxiliary chamber; and

[0023] Step vi), exposing the workpiece to the at least partial vacuum, such that the material printed onto the workpiece is processed by the at least partial vacuum.

[0024] According to a fifth aspect of the present invention, a method for producing printed workpieces is provided, comprising the following steps.

[0025] Step i), printing the wet material onto the workpiece; and

[0026] Step ii), while keeping the material moist, place the printed workpiece into the degassing chamber to degas the material.

[0027] Other specific aspects and features of the invention are set forth in the appended claims. Attached Figure Description

[0028] The invention will now be described with reference to the accompanying drawings (not to scale). In the drawings,

[0029] Figure 1 A cross-sectional side view of the degassing chamber according to a first embodiment of the present invention is shown schematically;

[0030] Figure 2 Schematic illustration of the use of Figure 1 A top view of the valve plate in the degassing chamber;

[0031] Figure 3 A cross-sectional side view of the degassing chamber according to a second embodiment of the present invention is schematically shown;

[0032] Figure 4 A cross-sectional side view of the degassing chamber according to a third embodiment of the present invention is shown schematically;

[0033] Figure 5 A cross-sectional side view of the degassing chamber according to a fourth embodiment of the present invention is schematically shown;

[0034] Figure 6 A perspective view of a printing press with an integrated degassing chamber according to another embodiment of the present invention is schematically shown; and

[0035] Figures 7 to 9 A schematic top view of a production line including a degassing chamber according to the present invention is shown.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1, 13, 20, 40, 66 - Degassing Chamber

[0038] 2 - Vacuum Source

[0039] 3.21 - Vacuum Storage

[0040] 4 - Storage Room

[0041] 5.22 - Processing Room

[0042] 6 - Input port valve

[0043] 7 - Output port valve

[0044] 8 - Conveying Mechanism

[0045] 9 - Storage opening

[0046] 10 - Processing chamber opening

[0047] 11 - Valve Plate

[0048] 12 - Through Hole

[0049] 14 - Air diffuser

[0050] 15 - Exhaust Valve Plate

[0051] 16 - Through Hole

[0052] 23 - Input airlock

[0053] 24 - Output airlock

[0054] 25 - Input Port Valve

[0055] 26 - Input storage valve

[0056] 27 - Output Port Valve

[0057] 28 - Output storage valve

[0058] 29, 41 - Input Transmitter

[0059] 30, 42, 44 - Processing Transmitters

[0060] 31, 45 - Output Transmitter

[0061] 43 - Teleportation Platform

[0062] 46 - Chain Bucket Elevator

[0063] 50 - Printing press

[0064] 51 - Entrance

[0065] 52 - Track

[0066] 53 - Printhead

[0067] 54 - Scraper

[0068] 55 - Positioning Mechanism

[0069] 56 - Exports

[0070] 60, 65, 70 - Production Line

[0071] 61 - Printing Press

[0072] 62 - Inspection Machine

[0073] 63 - Processor

[0074] 64 - Teleportation System

[0075] W, W1-W10 - Workpiece

[0076] T - Direction of transport. Detailed Implementation

[0077] Figure 1A schematic cross-sectional side view of a degassing chamber 1 according to a first embodiment of the invention is shown. The degassing chamber 1 has two main parts: a vacuum reservoir 3 defined by a storage chamber 4 and an auxiliary chamber, in this embodiment, a processing chamber 5. The vacuum reservoir 3 is in fluid communication with a vacuum source 2 (e.g., a high-speed single-stage vacuum pump, which is known in itself), thus creating and maintaining, for example, a partial vacuum or depressurization region of about 50 to 150 mBar within the vacuum reservoir 3 by operating the vacuum source 2. The vacuum reservoir 3 is larger than the processing chamber 5, for example having an internal volume approximately one hundred times larger than the internal volume of the processing chamber 5. The processing chamber 5 defines a processing area in which a workpiece W can be degassed by exposing it to the at least partial vacuum. One end of the processing chamber 5 is sealed by an inlet port valve 6, and the other opposite end is sealed by an outlet port valve 7. Each of the port valves 6 and 7 is movable between an open position and a closed position, in which the workpiece W is allowed to pass through the port valve between the exterior of the degassing chamber 1 and the processing chamber 5; in the closed position, the respective port valves 6 and 7 are fluidly sealed. Known valves (e.g., plate valves) can be used as the input port valve 6 and the output port valve 7. A conveyor mechanism 8, such as a conveyor belt or track, is disposed in the processing chamber 5 and is used to move the workpiece W from outside the degassing chamber 1 and position it within the processing area. As shown, the conveyor mechanism 8 is operable to convey the workpiece W from outside the degassing chamber 1 (to the left, as shown) along a linear conveying direction T parallel to the X-axis, through the input port valve 6 in the open position to feed the workpiece W into the processing area for degassing, and then through the output port valve 7 to send the workpiece W out to the outside of the degassing chamber 1 (to the right, as shown). In the case where the conveyor mechanism includes a conveyor belt or similar components, it should be noted that the conveyor belt can be located entirely within the processing chamber 5, thus not affecting the opening / closing operation of the input port valve 6 and the output port valve 7. To transfer workpiece W from outside the degassing chamber 1 or to the outside of the degassing chamber 1, the conveying mechanism 8 can cooperate with an externally located conveying mechanism (not shown) to receive or send workpiece W as needed. It should be noted that the workpiece W is relatively long, so when the corresponding port valve is open, the workpiece W can straddle the external conveying mechanism and the conveying mechanism 8 for safe transfer between the various conveying mechanisms. A storage valve is also provided, which in this embodiment includes a valve plate 11 that is movable between an open position and a closed position. In the open position, the processing chamber 5 and the vacuum storage tank 3 are in fluid communication; in the closed position, the storage valve is fluidly sealed. Figure 2A schematic top view of valve plate 11 is shown, comprising an array of through holes 12 extending through the entire thickness of valve plate 11. Corresponding reservoir openings 9 are located on the lower wall of reservoir chamber 4, while corresponding processing chamber openings 10 are located on the upper wall of processing chamber 5. Valve plate 11 is movably mounted to move between an open position and a closed position, in which each through hole 12 is aligned with a corresponding reservoir opening 9 and a corresponding processing chamber opening 10, while in the closed position each through hole 12 is not aligned with any reservoir opening 9 or processing chamber opening 10. The two-dimensional array of through holes 12 / openings 9, 10 is configured such that contour movement is possible on valve plate 11 to ensure consistent air velocity during evacuation of processing chamber 5.

[0078] Under the control of a single control device (not shown), such as a computer or processor, all valves (i.e., input port valve 6, output port valve 7, and storage valve) and the transmission mechanism 8 can be actuated and controlled by known devices (e.g., by their respective linear or rotary actuators). Similarly, the vacuum source 2 can also be controlled by the same or separate control device.

[0079] The operation is usually performed in the following order.

[0080] i) Vacuum source 2 continues to operate;

[0081] ii) Close the reservoir valve and evacuate the vacuum reservoir 3 to a low vacuum (e.g., about 50 mBar).

[0082] iii) Open input port valve 6;

[0083] iv) The workpiece W is sent into the processing chamber 5 via the conveyor mechanism 8;

[0084] v) Close input port valve 6 and output port valve 7;

[0085] vi) Open the reservoir valve to quickly equalize the pressure between the vacuum reservoir 3 and the processing chamber 5 (e.g., about 100 mBar).

[0086] vii) Degas the wet material printed onto the workpiece W in processing chamber 5;

[0087] viii) Close the reservoir valve;

[0088] ix) Open the output port valve 7 to release the gas in the processing chamber 5 into the atmosphere; and

[0089] x) The workpiece W is conveyed out of the processing chamber 5 by means of the conveying mechanism 8 through the output port valve 7.

[0090] The above process can be repeated for each workpiece requiring degassing. This dual-chamber arrangement allows for the maintenance of at least a partial vacuum in the vacuum reservoir 3 while workpiece W is being introduced into or removed from the processing chamber 5, ensuring that when the reservoir valve opens, at least a partial vacuum rapidly enters the processing chamber 5. This rapid degassing is essential for achieving an acceptable high throughput of workpiece W.

[0091] Figure 3 A schematic cross-sectional side view of the degassing chamber 13 according to a second embodiment of the present invention is shown. The degassing chamber 13 of this embodiment is... Figure 1 The degassing chamber 1 shown has many similarities, so there is no need to describe the similar parts in detail. In addition, for simplicity, the reference numerals for the similar parts are retained.

[0092] Compared to Figure 1 The degassing chamber shown in the figure, specifically the degassing chamber 13 of this second embodiment, has two significant differences. First, an air diffuser 14 is provided in the processing chamber 5. The air diffuser 14 is used to agitate the airflow during operation of the reservoir valve (e.g., ensuring airflow from the processing chamber to the vacuum reservoir 3 when the reservoir valve is open) to prevent damage to the still-wet printed material (e.g., printed gaskets) being degassed on the workpiece W; the air diffuser 14 also potentially serves to reduce or eliminate the resultant force acting on the workpiece W itself. The air diffuser can potentially take many forms, such as a mesh or perforated layer made of a rigid material (e.g., metal or plastic), or a device consisting of one or more baffles, wherein any form of air diffuser can be positioned relative to the reservoir valve according to the needs of the intended application.

[0093] Second, an exhaust valve is provided, which can be controlled to regulate the exhaust, i.e., control the airflow entering the processing chamber during exhaust, because uncontrolled airflow may interfere with the printing material or workpiece W. As shown, the exhaust valve includes an exhaust valve plate 15, which is constructed similarly to the reservoir valve plate 11 and has a through hole 16, which can engage with the exhaust opening (not shown) in the processing chamber 5 in the same manner as the reservoir valve.

[0094] Figure 1 and Figure 3 The illustrated embodiment includes separate input and output ports for the workpiece, allowing the workpiece to be conveyed in a single direction. However, it should be noted that in an alternative embodiment, a single input / output port with a single input / output port valve can be provided in the processing chamber. With this arrangement, the workpiece can be loaded into the processing chamber through the input / output port valve, degassed as described above, and then ejected from the processing chamber through the same input / output port valve. Reference is also made below. Figure 8 This type of arrangement is described.

[0095] As noted earlier, high production volumes are expected. It was also found that the degassing operation takes longer than the previous printing operation; for example, the degassing operation takes about 10 to 15 seconds, while the printing operation only takes about 1 second. Figure 4 A schematic cross-sectional side view of a degassing chamber 20 according to a third embodiment of the invention is shown, in which high throughput can be maintained. As in previous embodiments, a vacuum source 2 is provided for generating at least a partial vacuum in a vacuum reservoir 21 defined by a processing chamber 22 (in this embodiment, the processing area is located within the vacuum reservoir 21). Two auxiliary chambers are connected to the processing chamber 22, an input airlock 23, and an output airlock 24. Each of the airlocks 23, 24 is limited by two valves: the input airlock 23 includes an input port valve 25, and an input reservoir valve 26 is disposed between the input airlock 23 and the processing chamber 22; while the output airlock 24 includes an output port valve 27, and an output reservoir valve 28 is disposed between the output airlock 24 and the processing chamber 22. The input port valve 25 is movable between an open position and a closed position, in which the workpiece W is allowed to pass through the input port valve 25 between the exterior of the degassing chamber 20 and the input airlock 23; in the closed position, the input port valve 25 is fluid-sealed. The output port valve 27 is movable between an open position and a closed position. In the open position, it allows the workpiece W to pass through the outlet port valve 27 between the outside of the degassing chamber 20 and the outlet airlock 24. In the closed position, the output port valve 27 is fluid-sealed. The input reservoir valve 26 is movable between an open position and a closed position. In the open position, it is in fluid communication with the input airlock 23 and the vacuum reservoir 21. In the closed position, it is fluid-sealed. The output reservoir valve 28 is movable between an open position and a closed position. In the open position, it is in fluid communication with the output airlock 24 and the vacuum reservoir 21. In the closed position, it is fluid-sealed. Various types of valves known in the art, such as plate valves, can be used as these valves. A conveying mechanism is provided, comprising an input conveyor 29 located in an input airlock 23, a processing conveyor 30 located in a processing chamber 22, and an output conveyor 31 located in an output airlock 24. It is configured to sequentially convey workpiece W from outside the degassing chamber 20 along a conveying direction T parallel to the X-direction shown, passing it through an input port valve 25, then through an input airlock 23, and then through an input storage valve 26 into the processing chamber 22, positioning the workpiece W within the processing area. Subsequently, it is moved to the output airlock 24 through an output storage valve 28, and then removed from the degassing chamber 20 through an output port valve 27. Similar to the previous embodiments, the conveying mechanism can be manufactured using various methods known in the art, such as conveyor belts, tracks, etc.

[0096] Under the control of a single control device (not shown), such as a computer or processor, all valves (i.e., input port valve 25, output port valve 27, input storage valve 26, and output storage valve 28) and the transmission mechanism can be actuated and controlled by known means, such as by their respective linear or rotary actuators. Similarly, the vacuum source 2 can also be controlled by the same or separate control device.

[0097] The operation is usually performed in the following order.

[0098] i) Vacuum source 2 continues to operate;

[0099] ii) Close the input and output storage valves and evacuate the vacuum storage 21 to a low vacuum (e.g., about 50 mBar).

[0100] iii) Open input port valve 25;

[0101] iv) The workpiece W is transferred into the input airlock 23 via the input conveyor 29;

[0102] v) Close the input port valve 25 and the output port valve 27;

[0103] vi) Open the input reservoir valve 26 to quickly equalize the pressure between the vacuum reservoir 21 and the input airlock 23 (e.g., about 100 mBar).

[0104] vii) The workpiece W is moved to the processing area of ​​the processing chamber 22 by the coordinated movement of the input conveyor 29 and the processing conveyor 30. Degassing of the wet material printed on the workpiece W then begins.

[0105] viii) The input storage valve 26 is closed; once the input storage valve 26 is closed, the input port valve 25 can be opened to receive the new workpiece into the input airlock 23, and the input port valve 25 is closed again.

[0106] ix) The workpiece W continues to move along the conveying direction T in the processing chamber 22, thereby continuing to degas; during this period, the input storage valve 26 can be opened and a new workpiece can be moved from the input airlock 23 into the processing chamber 22, and the input storage valve 26 is closed after the transfer;

[0107] x) Open the output storage valve 28 to quickly equalize the pressure between the vacuum storage 21 and the output airlock 24 (e.g., about 100 mBar), and move the workpiece W from the processing chamber 22 to the output airlock 24 through the cooperation of the processing conveyor 30 and the output conveyor 31.

[0108] xi) Close the output storage valve 28;

[0109] xii) Open the output port valve 27 to release the gas in the output airlock 24 into the atmosphere;

[0110] xiii) The workpiece W is conveyed from the output airlock 24 to the outside of the degassing chamber 20 via the output port valve 27 by means of the output conveyor 31; and

[0111] xiv) Close the output port valve 27. Once the output port valve 27 is closed, the output storage valve 28 can be opened to allow new workpieces to enter the output airlock 24.

[0112] This process can continue indefinitely, thus achieving a constant and high output of degassed workpieces. Figure 4 In this system, the input airlock 23 and the output airlock 24 can each receive a single workpiece (W1 and W3, respectively), while the processing chamber 22 can receive three workpieces W2. However, depending on the relative dimensions of the workpieces and the chambers, each chamber can receive a different number of workpieces.

[0113] Figure 5 A schematic cross-sectional side view of the degassing chamber 40 according to a fourth embodiment of the present invention is shown. The degassing chamber 40 of this embodiment is similar to... Figure 4 The degassing chamber 20 shown in the figure has many similarities, so there is no need to describe the similar parts in detail. In addition, for simplicity, the reference numerals for similar parts are retained.

[0114] and Figure 4 Similar to the degassing chamber 20 shown, the degassing chamber 40 has a vacuum reservoir 21 defined by the processing chamber 22, and an input airlock 23 and an output airlock 24 serving as auxiliary chambers. In this embodiment, the degassing time for each workpiece W within the processing area of ​​the processing chamber 20 is increased without adversely affecting workpiece throughput. As in previous embodiments, the vacuum reservoir 21 is large, and in this embodiment, the available space is utilized more efficiently by increasing the length of the conveying path for each workpiece W within the processing area. In the illustrated embodiment, this is achieved by arranging a bucket elevator 46 within the processing chamber 22. The bucket elevator 46 includes a plurality of spaced-apart conveyor platforms 43, each configured to support a single workpiece W thereon, and the bucket elevator 46 is capable of transferring workpieces between the respective conveyor platforms 43 and processing conveyors 42, 44. Suitablely, each conveyor platform may include a conveyor belt, track, etc. The conveyor platforms are arranged to rotate in a generally clockwise direction around the bucket elevator 46 while remaining horizontal throughout the range of motion.

[0115] More specifically, the conveying mechanism includes an input conveyor 41 located in the input airlock 23, a first processing conveyor 42 located in the processing chamber 22, multiple conveying platforms 43 arranged on the bucket elevator 46, a second processing conveyor 44 located in the processing chamber 22, and an output conveyor 45 located in the output airlock 24. The conveying mechanism is configured to sequentially convey workpieces W from outside the degassing chamber 40 along a conveying direction T parallel to the X direction shown in the figure (excluding the intermediate portion where the workpiece moves on the bucket elevator 46), allowing them to pass through the input port valve 25, then through the input airlock 23, and then through the input storage valve 26 into the processing chamber 22, positioning the workpiece W within the processing area. Subsequently, it is moved to the output airlock 24 through the output storage valve 28, and then removed from the degassing chamber 20 through the output port valve 27. It can be seen that in the positions shown, the two lowest conveying platforms 43 are at the same height as the first processing conveyor 42 and the second processing conveyor 44. At this location, workpiece W6 can be received from the first processing conveyor 42 onto the conveyor platform 43, while workpiece W8 can be transferred from the conveyor platform 43 to the second processing conveyor 44. Similar to previous embodiments, the conveying mechanism can be manufactured using various methods known in the art, such as conveyor belts, tracks, etc. As shown, the input conveyor 41 carries a single workpiece W4, the first processing conveyor 42 carries a single workpiece W5, each conveyor platform 43 can carry single workpieces W6, W7, and W8 respectively, the second processing conveyor 44 carries a single workpiece W9, and the output conveyor 45 carries a single workpiece W10. With this arrangement, the degassing time can be several times longer compared to the linear arrangement of previous embodiments.

[0116] Because RTV silicone begins to solidify quickly after printing, and degassing can only occur when the silicone is sufficiently moist, it is crucial to perform degassing immediately after printing for this application. The fastest way is to provide a degassing chamber integrated within the printing press. Figure 6 An integrated degassing chamber 20 (e.g., according to another embodiment of the invention) is illustrated schematically. Figure 4A perspective view of this printing press 50 (shown as a degassing chamber). The main components of the printing press 50 with screen printing capabilities are well-known and not particularly relevant to the purposes of this invention, and therefore will not be described in detail. However, those skilled in the art will understand that the printing press includes an inlet 51 for receiving workpieces to be printed from the front portion of the production line, and a conveying mechanism, which includes a track 52 for conveying workpieces within the printing press 50 along a conveying direction T parallel to the X direction shown. In this embodiment, the printing-functional portion of the printing press 50 and the integrated degassing chamber 20 share the conveying mechanism. The printing press 50 includes a print head 53 with a squeegee 54, which operates to squeegee a printing medium such as RTV silicone onto the workpiece below through a patterned template or screen (not shown), wherein the workpiece is generally positioned by a positioning mechanism indicated by reference numeral 55. The printing press also includes an outlet 56 on its downstream side, through which the printed workpiece can be conveyed by the conveying mechanism and received by a cooperating conveyor system (not shown) of a subsequent production line.

[0117] Figures 7 to 9 A schematic cross-sectional top view of various production lines, each including a degassing chamber according to the invention, is shown. These production lines are suitable for manufacturing fuel cells including gaskets printed with RTV silicone material. Each production line uses a conveying system 64 (e.g., conveyor belt, track, etc.) known in the art to convey workpieces along a direction T parallel to the X-axis. The conveying mechanism for each degassing chamber shown is integrated within the entire conveying system 64. It should be noted that the production line can be a single line, where a component of the production line, such as a printing press, can only be operated for printing a single workpiece at a time; or a dual line, where components can be operated in parallel configuration to process two separate workpieces. Figure 7 and Figure 9 The production line shown can be a single line or a double line, while Figure 8 The production line shown is a dual-line line only. Those skilled in the art will recognize that additional or replaceable components may be present in the production line, including components upstream of the printing press and downstream of the degassing chamber; therefore, these illustrations are merely exemplary. For simplicity, reference numerals for identical components have been retained in these figures wherever possible.

[0118] Figure 7 A cross-section of production line 60 is shown, on which a dedicated printing machine 61, i.e., a screen printing machine, is located upstream, and a dedicated degassing chamber 20 (e.g., ...) is located downstream, either directly behind or immediately following it. Figure 4 (The degassing chamber is shown). An inspection machine 62 is located downstream of the degassing chamber 20 and is used to inspect the quality of the printed workpiece. Further downstream is a processing machine 63, which may include, for example, an assembly machine, a reflow oven, etc. Of course, other processing machines may also be located downstream.

[0119] Figure 8A cross-section of production line 65 is shown, on which a dedicated dual-line printing press 61 is located upstream. Downstream, directly following or immediately after the printing press 61, are multiple (four in this case) dedicated degassing chambers 66, two of which are connected via hubs 67 to each channel of a conveyor system 64, allowing printed workpieces to be selectively conveyed to a specific degassing chamber 66 after leaving the printing press 61. Each degassing chamber 66 may include features similar to... Figure 1 or Figure 3 The degassing chamber shown is, as previously described, only a single input / output port. Therefore, each degassing chamber 66 forms a pile along the production line. Providing multiple degassing chambers in this way increases workpiece throughput. Immediately following the degassing chamber 66 in the downstream direction is an inspection machine 62, which is used to inspect the quality of the printed workpieces. Further downstream is a processing machine 63, which may include, for example, an assembly machine, a reflow oven, etc. Of course, other processing machines may also be provided downstream.

[0120] Figure 9 A cross-section of a production line 70 is shown, on which a printing press 50 including an integrated degassing chamber 20 is mounted, similar to... Figure 6 The printing press shown is also located upstream. Immediately following downstream is an inspection machine 62, which is used to inspect the quality of the printed workpieces. Further downstream is a processing machine 63, which may include, for example, an assembly machine, a reflow oven, etc. Of course, other processing machines may also be located downstream.

[0121] The above embodiments are merely exemplary, and other possible solutions and alternatives within the scope of the invention will be readily apparent to those skilled in the art. For example, although the invention has been described with particular reference to printing and degassing of silicone in fuel cells and RTVs, the described apparatus can be used for degassing many different types of wet printing materials for many different applications.

Claims

1. A degassing chamber for degassing material located on a workpiece, comprising: A vacuum source, which is used to generate at least a partial vacuum. A vacuum reservoir, which is in fluid communication with the vacuum source, enables the generation and maintenance of the at least partial vacuum within the vacuum reservoir. Auxiliary room, A port valve is movable between an open position and a closed position, wherein the open position allows a workpiece to pass through the port valve between the outside of the degassing chamber and the auxiliary chamber, and the closed position provides a fluid seal for the port valve. A reservoir valve is movable between an open position and a closed position, wherein in the open position the auxiliary chamber and the vacuum reservoir are in fluid communication, and in the closed position the reservoir valve is in fluid seal. A processing area capable of degassing the material of the workpiece within the processing area, wherein the processing area is located in the auxiliary chamber, and A conveying mechanism for moving the workpiece from outside the degassing chamber and positioning it within the processing area.

2. The degassing chamber according to claim 1, wherein, The vacuum storage device is larger than the auxiliary chamber.

3. The degassing chamber according to claim 2, wherein, The vacuum storage unit has an internal volume approximately 100 times that of the auxiliary chamber.

4. The degassing chamber according to claim 1, wherein, The reservoir valve includes a valve plate with a through-hole, the valve plate being movably mounted to move between an open position and a closed position; in the open position, the through-hole is aligned with an opening on the outer wall of the vacuum reservoir and / or the auxiliary chamber, and in the closed position, the through-hole is not aligned with the opening.

5. The degassing chamber according to claim 4, wherein, The valve plate is mounted between the auxiliary chamber and the vacuum reservoir, each of which includes an opening on its outer wall aligned with the through hole to provide fluid communication between the opening and the through hole when the valve plate is in the open position.

6. The degassing chamber according to claim 4, wherein, The valve plate is installed in one of the auxiliary chamber and the vacuum reservoir.

7. A production line for producing workpieces, comprising a printing press and a degassing chamber as claimed in any one of claims 1 to 6, wherein the degassing chamber is located on the production line to receive the workpiece after it has been printed by the printing press.

8. The production line according to claim 7, wherein, Each of the workpieces includes a component of a fuel cell, and the material includes gaskets for each component.

9. A printing machine for printing a printing medium onto a workpiece, comprising a degassing chamber for degassing the printing medium after it has been printed onto the workpiece, wherein, The degassing chamber includes the degassing chamber according to any one of claims 1 to 6.

10. A method for degassing material printed onto a workpiece, comprising the following steps: Step i), provide the degassing chamber according to claim 1; Step ii), using the vacuum source to generate and maintain at least a partial vacuum in the vacuum reservoir; Step iii), insert the workpiece into the auxiliary chamber through the port valve; Step iv), close the port valve; Step v), open the reservoir valve to increase the vacuum in the auxiliary chamber; as well as Step vi), exposing the workpiece to the at least partial vacuum, such that the material printed onto the workpiece is processed by the at least partial vacuum.

11. The method according to claim 10, wherein, In step i), the degassing chamber is positioned adjacent to the printing press on the production line.

12. The method according to claim 10, wherein, In step i), the degassing chamber is located inside the printing press.

13. The method according to claim 10, wherein, The workpiece includes components of a fuel cell, and the material includes gaskets for the components.

14. The method of claim 10, wherein, The material includes room temperature vulcanized silicone.

15. A method for producing gaskets for fuel cells, comprising printing material onto a workpiece using the method according to any one of claims 10 to 14 and degassing the printed material.

16. The method according to claim 15, wherein, The step of printing material onto a workpiece includes screen printing the material onto the workpiece.

17. A method for producing printed workpieces, comprising the following steps: Step i), printing the wet material onto the workpiece; as well as Step ii), while keeping the material moist, place the printed workpiece into the degassing chamber as described in claim 1 to degas the material.

18. The method according to claim 17, wherein, Step i) includes screen printing the wet material onto the workpiece.

19. The method according to claim 18, wherein, Steps i) and ii) are performed within the same machine.

20. The method according to claim 18, wherein, Step i) is performed using a printing press on the production line, and step ii) is performed using a degassing chamber that follows directly behind the printing press on the production line.

21. The method according to any one of claims 17 to 20, wherein, The printed workpiece includes components of a fuel cell.

22. The method according to claim 21, wherein, The fuel cell includes a polymer electrolyte membrane fuel cell.

23. The method according to claim 21, wherein, The material includes gaskets for the component.

24. The method according to any one of claims 17 to 20, 22 to 23, wherein, The material includes room temperature vulcanized silicone.

25. The method according to claim 21, wherein, The material includes room temperature vulcanized silicone.

26. The method according to claim 17, wherein, The material is degassed using the method for degassing material printed on a workpiece according to claim 10.

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