Multi-material dispensing and coating system

Abstract

Systems and methods for dispensing liquid materials, applicable to applications such as coating flexible membranes. The membrane is coated by dispensing a rheological material onto its surface while it is being drawn through a gap between a pair of rollers. The gap defines the thickness of the material layer applied to the membrane and is maintained at a desired width by microfilaments positioned through the gap. Another membrane, applied from the membrane to which the rheological material is applied across the gap, facilitates the coating of the layer and allows the contact area of ​​the second membrane relative to the gap to be adjusted, for example, when changing materials or when the coated membrane is abraded or deformed.

Description

[0001] Related applications

[0002] This application is a divisional application of the invention patent application with application number 201980018586.5.

[0003] This application claims priority to U.S. Provisional Application No. 62 / 643,263, filed March 15, 2018. Technical Field

[0004] The present invention generally relates to systems and methods for dispensing liquid materials, for example, that can be used in applications such as coating flexible films, and particularly to such systems as those configured to dispense multiple liquid materials from multiple reservoirs. Background Technology

[0005] Many systems exist for dispensing liquid materials onto substrates. Typically, such dispensing devices fall into two categories: "on-demand titration" and "continuous." In on-demand titration, the material is coated onto the substrate in the form of individual droplets delivered from a nozzle. In continuous coating, the material is dispensed onto the substrate in a continuous flow. Regardless of the dispensing method, precise control of the dispensing pressure is usually required. Different materials to be dispensed require different dispensing pressures due to their varying rheological properties. Therefore, it is difficult to use a single dispensing device for a wide range of liquid materials. Summary of the Invention

[0006] Embodiments of the present invention provide precise dispensing of liquid material at a constant volume and tunable frequency, without high tolerance requirements on the pressure used for such dispensing or on the material being dispensed. The system configured according to the invention is characterized by a relatively fast open / close switching time, which allows for rapid switching between materials used for dispensing. Dispensing is accomplished by two independent liquid flow mechanisms: an imprecise pressure-transmitting dispenser and a piston-transmitting mechanism. In one embodiment, the dispensing system can be used within an apparatus for coating thin and precise layers of rheological material onto a flexible membrane. In such apparatus, the thickness of the layer applied to the membrane is controlled by the spacing or gap between two rollers, wherein the gap width is maintained by two or more microfilaments disposed in the gap between the rollers. The coating apparatus can also be used without a multi-material dispensing system (e.g., when only a single material is to be deposited onto the membrane), and in some embodiments, a conventional syringe can be used as the dispenser. Therefore, aspects of multi-liquid dispensing systems and coating systems will be described individually and in combination with each other.

[0007] In one embodiment of the invention, a coating apparatus includes a dispensing unit arranged to apply a rheological material onto a flexible membrane. The membrane is arranged to draw a gap between a pair of rollers through the coating apparatus. The gap defines the thickness of the rheological material layer applied to the membrane by being positioned after the rheological material has been applied to a coating region of the membrane in the direction of membrane travel. The gap has a width maintained by filaments suspended through the gap as a desired spacing distance between the rollers.

[0008] The coating apparatus may include multiple filament holders mounted on a frame slidably fixed to a first track formed by one or more guide rails and fixed to the guide rail holders, such that a selected filament holder with filaments of the desired thickness can be positioned close to the gap between the pair of rollers. Each filament holder may be displaceable along a corresponding second track in a direction perpendicular to the first track. In such an arrangement, each filament holder may include a holder frame, rollers, and filament supports mounted to the holder frame, with one end of a corresponding filament of each filament holder fixed to a corresponding first roller and the other end of the corresponding filament fixed to a corresponding second roller, wherein the middle portion of the corresponding filament is supported by the filament supports, such that the corresponding first and second rollers rotate about a corresponding axis of rotation to adjust the tension of the corresponding filament. The gap width is then defined by two filament sub-assemblies, each filament sub-assembly including a frame capable of linear translation along guide rails to position a selected filament holder with filaments of the desired thickness adjacent to the surface of the rollers.

[0009] In various embodiments of the invention, the microfilament may be suspended through the gap and in contact with the membrane, with one of the rollers but not the membrane, or with each of the pair of rollers but not the membrane.

[0010] Furthermore, the membrane to which the rheological material is applied is opposite to the second membrane across the gap. Therefore, the microfilament can be suspended through the gap and in contact with both the membrane to which the rheological material is applied and the second membrane, with one of the rollers but not the membrane to which the rheological material is applied, or with each of the pair of rollers but not the membrane or the second membrane to which the rheological material is applied.

[0011] Another embodiment of the invention provides coating the film by dispensing a first rheological material onto the surface of the film while the flexible film is being drawn through a gap between a pair of rollers. The gap defines the thickness of the rheological material layer applied to the film by being positioned thereafter in which the rheological material is applied to a coating region of the film in the direction of film travel, and the gap is maintained at a certain width by positioning a first filament through the gap during the dispensing of the rheological material.

[0012] As indicated above, the membrane to which the first rheological material is applied may be opposite the second membrane across the gap, and the contact area of ​​the second membrane may be adjusted across the gap separating it from the membrane to which the rheological material is applied. In some cases, after adjusting the contact area of ​​the second membrane, the second rheological material is dispensed onto the surface of the flexible membrane.

[0013] During the dispensing of the rheological material onto the membrane, the width of the gap can be adjusted by replacing the first microfilament with a second microfilament of a different thickness than the first microfilament passing through the gap. Subsequently, the contact area of ​​the second membrane can be adjusted across the gap to which the rheological material is applied. Alternatively, the dispensing of the first rheological material can be paused while replacing the first microfilament with a second microfilament of a different thickness than the first microfilament passing through the gap, and subsequently, the contact area of ​​the second membrane can be adjusted across the gap to which the rheological material is applied. In other cases, the dispensing of the first rheological material can be stopped to facilitate the dispensing of the second rheological material onto the surface of the membrane; and the width of the gap can be adjusted by replacing the first microfilament with a second microfilament of a different thickness than the first microfilament passing through the gap.

[0014] In another embodiment of the invention, a dispensing unit for dispensing liquid material includes: a hollow reservoir configured to receive a syringe and having an elongated nozzle at one end of the reservoir; a piston including a shaft disposed therein; and a bracket adapted to receive the nozzle and the piston of the reservoir. The nozzle of the reservoir, when supported in the reservoir, provides a fluid path for liquid material dispensed from the syringe, and the bracket is adapted to receive the nozzle of the reservoir such that the fluid path for the liquid material is oriented toward a nozzle disposed in the bracket. The nozzle also has an orifice near its end, and the bracket is adapted to receive the piston, the piston being oriented relative to the nozzle of the reservoir such that the shaft of the piston is aligned with the orifice and the nozzle in the nozzle. The nozzle also has an orifice near its end, and the bracket is adapted to receive the piston, the piston being oriented relative to the nozzle of the reservoir such that the shaft of the piston is aligned with the orifice and the nozzle in the nozzle. Therefore, the shaft is displaceable toward the nozzle through the orifice.

[0015] In some embodiments, the bracket includes a rail mount adapted for connection to a rail interface of the dispenser system. Furthermore, the piston may include a tip at its top and an air connector positioned along its longitudinal length. An extension of the piston through a hollow shaft of the shaft is in fluid communication with the air connector. The dispensing unit may also include a syringe received within a reservoir, and the syringe may have a plunger and a cap.

[0016] Other embodiments of the invention provide a dispensing system having one or more of the dispensing units described above. These dispensing units are arranged to be laterally displaced along a length of the dispensing system defined by a lead screw. A first electric motor is configured to drive the lead screw clockwise or counterclockwise to displace the dispensing units along the length of the dispensing system. The dispensing system further includes means for selectively actuating a piston of the dispensing unit to displace a corresponding axis of the piston's shaft relative to the nozzle of the dispensing unit's bracket.

[0017] In various embodiments, the means for selectively actuating the piston of the dispensing unit includes a piston tip capturing unit capable of translating within a piston capturing block parallel to the longitudinal axis of a corresponding piston in the piston of the dispensing unit. A second electric motor is coupled to rotate a piston displacement shaft clockwise or counterclockwise, the piston displacement shaft having a piston displacement cam at one end. The piston tip capturing unit includes a cam recess for receiving the piston displacement cam and a slotted recess for receiving the tip of a corresponding shaft when positioned above the corresponding shaft in the piston. Thus, as the piston displacement cam rotates with the piston displacement shaft, the piston tip capturing unit translates in a direction defined by the longitudinal axis of the piston, and any corresponding piston tip located at the top of the corresponding piston fixed within the slotted recess in the piston also translates along the longitudinal axis of the corresponding piston.

[0018] The end of the piston displacement shaft is offset from the axis of rotation of the piston displacement shaft, and the piston displacement cam is elliptical in shape. Preferably, the piston tip capturing unit, which includes the cam recess, is fixed so as to remain stationary along an axis orthogonal to the longitudinal axis of the corresponding piston in the piston.

[0019] In some cases, the distribution system includes a third electric motor coupled to a rotating piston stroke shaft having a piston stroke cam at one end. This piston stroke cam is positioned to engage a displaceable cam along the piston displacement shaft. The displaceable cam is adjacent to a spring-loaded wedge connected to the piston displacement cam, such that the displaceable cam, through movement in engagement with the piston stroke cam, forces the wedge to open, thereby causing the center of rotation of the piston displacement cam to move radially away from the axis of rotation of the piston displacement shaft. In this way, the stroke length of the piston shaft can be adjusted.

[0020] Other embodiments of the invention provide a method for dispensing material. According to the method, one or more syringes are filled with a liquid material of interest, and each syringe is subsequently placed in a corresponding reservoir among a plurality of reservoirs in a dispenser unit. When a corresponding piston shaft of a piston associated with the plurality of reservoirs is activated, a corresponding pressure of the syringe is set for dispensing droplets of the liquid material of interest (e.g., by adjusting the positioning of the corresponding plungers of the one or more syringes), and a control unit of the dispenser unit is programmed with a desired print pattern of the liquid material of interest. An eccentricity of a piston displacement cam of the dispenser unit is set, the eccentricity defining the piston shaft stroke length of the piston. Thereafter, a printing operation is performed according to the desired print pattern, wherein during the printing operation, the actuator dispenses the liquid material from the reservoir by displacing one of the corresponding piston shafts of the pistons associated with the plurality of reservoirs along its longitudinal length, thereby producing the droplets of the liquid material. The liquid material of interest can be replaced as needed during the printing operation.

[0021] In one configuration, displacement of each corresponding piston shaft is achieved via a rotating shaft in the actuator, one end of which is offset from its axis of rotation, thereby forcing a piston tip capturing unit to displace in a direction parallel to the longitudinal length of the piston as the shaft rotates. The piston tip capturing unit captures the tip of the selected corresponding piston in a groove-shaped recess, the tip being positioned within the recess as the piston tip capturing unit moves, thus causing the shaft of the selected corresponding piston to also move. Additionally, a second actuator in the actuator can displace the plurality of reservoirs of the dispensing unit along the length of the dispensing unit between movements of the shaft of each selected corresponding piston by rotating a lead screw clockwise or counterclockwise. Furthermore, a third actuator in the actuator can change the piston shaft stroke length by altering the offset distance between the end of the shaft and its axis of rotation.

[0022] Another embodiment of the invention provides a coating apparatus having one or more dispensing units of the type discussed above. The dispensing units are arranged to apply rheological material from syringes housed within respective hollow reservoirs of the dispensing units onto a flexible film drawn between a pair of rollers, the flexible film being below a respective nozzle of the dispensing unit and passing through a gap defined by a pair of rollers of the coating apparatus. The gap defines the thickness of the rheological material layer applied to the film by being positioned after the rheological material from the syringes has been applied to a coating region of the film in the direction of film travel, and the gap is held at a desired separation distance between the rollers by microfilaments suspended through the gap. To allow for different gap widths, multiple microfilament holders can be mounted on a frame, and the frame is slidably fixed to a first track formed by one or more guides fixed to guide rail holders, such that a selected microfilament holder with a desired thickness of microfilament can be positioned close to the gap between the pair of rollers.

[0023] Each filament holder can be displaced along a corresponding second track in a direction perpendicular to the first track. Furthermore, each filament holder may include a holder frame, rollers, and filament supports mounted to the holder frame. In such cases, each filament holder may include a holder frame, rollers, and filament supports mounted to the holder frame, with one end of a corresponding filament of each filament holder fixed to a corresponding first roller and the other end of the corresponding filament fixed to a corresponding second roller, wherein the middle portion of the corresponding filament is supported by the filament support, such that the corresponding first and second rollers rotate about a corresponding axis of rotation to adjust the tension of the corresponding filament. In other embodiments, the gap may be defined by two filament sub-assemblies, each filament sub-assembly including a frame capable of linear translation along a guide rail to position a selected filament holder with a filament of desired thickness adjacent to the surface of the roller.

[0024] These and other embodiments of the present invention are described in detail below. Attached Figure Description

[0025] The invention is illustrated by way of example, not limitation, in the accompanying drawings, in which:

[0026] Figure 1 An example of a multi-material dispensing system having multiple liquid reservoirs according to an embodiment of the present invention is shown.

[0027] Figure 2A and Figure 2B Detailed description for Figure 1 The modular storage of the dispenser unit in the multi-material dispensing system shown herein, wherein Figure 2ADescribe a side view of the storage device, and Figure 2B Describe its cross-sectional view.

[0028] Figure 2C Showing for use with, such as Figure 2A and Figure 2B A cross-sectional view of the piston used in conjunction with those modular storage units depicted in the figure.

[0029] Figure 2D A view is shown of a modular reservoir that houses the syringe and is fitted with a cap 41; the modular reservoir, together with the piston positioned therein, is assembled in a bracket to prevent liquid material from being released from the reservoir's inlet tube.

[0030] Figures 3A to 3D This demonstrates the dispensing of liquid material droplets from a syringe positioned within a modular reservoir.

[0031] Figure 4A and Figure 4B exhibit Figure 1 The multi-material dispensing system consists of parts that actuate pistons to allow the dispensing of droplets of liquid material from a syringe positioned within a modular reservoir via an electric motor and a rotating shaft.

[0032] Figures 5A to 5C The figure shows how one end of the shaft shown in Figure 4 is offset from the axis of rotation, forcing the piston tip capture unit to move vertically as the shaft rotates, thereby pulling the piston shaft upward.

[0033] Figure 6 The rotation of motor 16, which controls the piston stroke of the cam via an electric motor, causes the cam to move along a rotation axis.

[0034] Figure 7A and Figure 7B Provides a view of the dispenser unit, showing how the individual pistons are organized within the dispenser unit and how their piston tips are captured by the tip-capturing unit.

[0035] Figures 8A to 8C The distributor unit is repositioned along the lead screw of the multi-material dispensing system by means of a motor rotating the lead screw clockwise or counterclockwise.

[0036] Figures 9A to 9C This illustrates how the rotation of the lead screw allows for the precise positioning of the dispensed droplets.

[0037] Figure 10 The process for dispensing materials according to an embodiment of the present invention is illustrated.

[0038] Figure 11 An example of a coating apparatus according to an embodiment of the present invention is shown, the coating apparatus being used for coating by means such as Figure 2DThe diagram shows an applicator with a modular reservoir containing a syringe applying a rheological material coating onto a flexible membrane.

[0039] Figure 12 Show Figure 11 The coating apparatus shown contains details of the gap in which the flexible membrane travels, with the gap width defined by two tensioned microfilaments held within the gap.

[0040] Figure 13 and Figure 14 exhibit Figure 1 The multi-material distribution system shown is Figure 11 Used together with the coating system shown in the figure.

[0041] Figure 15 A perspective view depicting a coating system according to an embodiment of the present invention is shown, wherein microfilaments of varying thickness can be used to define an adjustable gap width between rollers.

[0042] Figure 16 Describe in more detail Figure 15 A perspective view of the microfilament assembly shown;

[0043] Figure 17 Describe in more detail Figure 15 A perspective view of the microfilament assembly shown;

[0044] Figure 18 Describe in more detail Figure 15 The diagram shows a perspective view of the rollers of a coating system according to an embodiment of the present invention, wherein the gap between the rollers is defined by two microfilament assemblies.

[0045] Figures 19A to 19C Showcase targeting Figures 11 to 18 The embodiments depicted show different arrangements of the microfilaments relative to a pair of rollers and the associated membrane engaged with the pair of rollers. Detailed Implementation

[0046] First refer to Figure 1 An example of a multi-material dispensing system 10 with multiple liquid reservoirs 14 is shown. Precision dispensers typically require complex control of dispensing pressure, which often depends on the rheological properties of the dispensing material. This system simplifies the dispensing procedure, enabling precise dispensing at tunable frequencies without the typical requirements associated with such systems. The modular nature of this system also provides easy replacement of consumable parts, thus facilitating easy maintenance. Compared to conventional dispensing systems, this dispensing system offers:

[0047] ■ Higher tolerance for pressure control (i.e., this system does not require the same level of precise control over the distributed pressure as conventional units);

[0048] ■ Less dependence on the rheological properties of the distributed materials;

[0049] ■ Compactness, simplicity, and low cost;

[0050] ■ Precise, high-level control achieved through a range of frequency allocations;

[0051] ■ Quickly switch between opening / closing times;

[0052] ■ It functions as a single system, either a valve or a piston pump, without any additional subsystems;

[0053] ■ Quick switching between materials used for dispensing;

[0054] ■ Two dispensing schemes: "on-demand titration" and "continuous" titration in a single unit; and

[0055] ■ Direct control of the dispenser head to achieve one-dimensional droplet positioning.

[0056] The distribution system 10 mainly consists of five parts: a distributor unit 12 with one or more reservoirs 14, a piston 34 for distributing fluid, an actuator (or motor) 18 that allows the system to switch between materials to be distributed, an actuator 20 that moves the piston to distribute materials, and an actuator that changes the piston stroke length (not shown in this view, see [link]). Figure 6 Component 16). Further reference. Figure 2A and Figure 2B The distributor unit 12 includes one or more modular storage units 14. Figure 1 The diagram shows four storage units 14; however, this is for illustrative purposes only. In various embodiments of the invention, one, two, three, four, or more storage units may be present. Figure 2A A side view of a single reservoir 14 mounted in a bracket 24 of the dispenser unit is shown. The bracket 24 may include a rail mount 26, which can be secured to a rail 29 when the dispenser unit is attached to other components of the dispenser system 10.

[0057] Figure 2B This is a cross-sectional view of the reservoir 14 and the bracket 24. The reservoir is hollow to accommodate the syringe 40 (see [reference]). Figure 2D The reservoir 14 includes an elongated nozzle 28. The nozzle 28 provides a fluid path for the liquid material from the syringe supported in the reservoir 14 toward the nozzle 30. At the top of each nozzle 28, an orifice 31 is located near the end of the nozzle 28 (see [link to documentation]). Figure 3B The hole 31 is used to receive the piston shaft 48 of the piston 34. A corresponding hole 33 is provided at the bottom of each connector 28 for the piston shaft to discharge liquid droplets 50 from the reservoir connector (see...). Figure 3B ).

[0058] Above the nozzle 30 is the piston recess 32, and the piston 34 is positioned within the piston recess 32 (see...). Figure 2A and Figure 2D As will be described below, actuation of piston 34 controls the dispensing of liquid material droplets 50 from liquid reservoir tube 28 (see below). Figure 3D ).like Figure 2A and Figure 2C As shown, piston 34 includes a tip 36 located at its top and an air inlet 38 positioned along its longitudinal length. Hollow shaft 42 is in fluid communication with air inlet 38 and extends through piston shaft 48 such that a small amount of compressed air or other gas can be injected through hollow shaft 42 to discharge droplets of liquid material through nozzle 30 if desired and / or required.

[0059] During assembly, such as Figure 2D As shown, the modular reservoir 14 houses the syringe 40 and has a cap 41. The syringe 40 includes a plunger 46 and contains liquid material to be dispensed. A piston 34 is positioned within a recess 32 in the holder 24, and a piston shaft 48 extends to prevent liquid material from being released from the reservoir nozzle.

[0060] like Figures 3A to 3D As shown, when the syringe 40 is in the position inside the reservoir 14, in order to dispense droplets of liquid material, the piston shaft 48 is retracted to a position outside the reservoir nozzle 28, allowing liquid to enter the reservoir nozzle 28. Then, when the piston shaft 48 extends vertically downward along the longitudinal axis of the piston 34 ( Figures 3B to 3C ), forming precisely sized droplets at the nozzle 30 of the reservoir 14. Finally, when the piston shaft 48 has been fully extended ( Figure 3D ), and droplet 50 was released.

[0061] In some cases, such as when the dispensed liquid material is relatively viscous and / or when the nozzle diameter is relatively small, it may be necessary or desirable to apply a small amount of compressed air through the air connector 38 and the hollow shaft 42 to cause the droplets 50 to separate. After the droplets 50 have been dispensed, the piston shaft 48 returns to its initial position. Figure 3A This allows for refilling of the reservoir nozzle 28, enabling the formation and dispensing of the next droplet. Alternatively, when the piston shaft 48 is in its retracted position, the syringe plunger 46 can be used to dispense the next droplet. Figure 2D Pressure is applied to distribute fluid droplets.

[0062] Piston 34 therefore has two functions. When pressure is applied to reservoir 14 (i.e., to the liquid in syringe 40 within reservoir 14), piston 34 acts as a valve, thereby controlling the droplet deposition frequency and droplet size. If a low pressure is applied to the reservoir (i.e., less than the pressure required to expel droplets from the reservoir nozzle), piston 34 can be used to force fluid through nozzle 30. Hollow shaft 42 acts as a passage inside the piston, providing space for gas (or other fluids) that can be pressurized in sync with the movement of the piston shaft, causing droplets to separate from the nozzle at the end of the piston. The piston is spring-loaded (see [link to piston description]). Figures 9A to 9C Components 108 in the memory are used to ensure that they return to the closed position when the memory is not in use. Figure 3D ).

[0063] The actuation of the corresponding piston in piston 34 is achieved by rotating shaft 60 via electric motor 20. (Reference) Figure 1 , Figures 4A to 4B and Figures 5A to 5C The end of shaft 60 is offset from the rotation axis 62, thereby forcing the piston tip capturing unit 64 to move vertically (i.e., parallel to the piston shaft axis) as the shaft rotates. The piston tip capturing unit 64 includes a groove-shaped recess 70 within which the piston tip 36 is located (see...). Figure 7B Therefore, as the piston tip capturing unit moves vertically, the piston shaft 48, which is mechanically coupled to the tip 36 within the piston 34, also moves vertically (i.e., along its longitudinal axis).

[0064] More specifically, the movement of the piston tip capturing unit 64 is influenced by the rotation of the piston displacement cam 66 located at the end of the shaft 60. The elliptical piston displacement cam 66 is positioned within the cam recess 68 of the piston tip capturing unit 64. For example... Figure 1 As shown, the piston tip capturing unit itself is supported in the piston capturing block 69, allowing it to translate vertically (i.e., parallel to the longitudinal axis of the piston 34). When the motor 20 rotates the shaft 60, the piston displacement cam 66 rotates within the elliptical cam recess 68 of the piston tip capturing unit 64. The piston tip capturing unit 64, including the cam recess 68, is fixed so as to remain stationary along an axis orthogonal to the longitudinal axis of the piston. Therefore, when the piston displacement cam 66 rotates with the shaft 60, the piston tip capturing unit 64 is translated vertically (i.e., in the direction defined by the longitudinal axis of the piston 34). Because the piston tip 36 is fixed within the slotted recess 70, the piston shaft 48 connected to the tip 36 is also translated vertically (i.e., along its longitudinal axis). Thus, the piston 34 can be actuated to control the deposition of liquid droplets.

[0065] Changing the piston stroke length is achieved by altering the offset distance between the end of shaft 60 and its axis of rotation. For example... Figure 6As shown, the electric motor 16 rotates a piston stroke cam 80, which in turn displaces a cam 82 along a shaft 60. The cam 82 is connected to a pin 86 via a bracket 84. As the pin 86 is displaced along the shaft 60 by the movement of the cam 82, the pin 86 presses against a spring-loaded wedge 90. The wedge 90 is connected to a piston displacement cam 66 such that when the wedge is forced open by the movement of the pin 86, the center of rotation of the piston displacement cam 66 moves radially away from the axis of rotation of the shaft 60 (see [link to diagram]). Figures 5A to 5C ).

[0066] The system can rapidly switch between dispensing various materials by driving the lead screw 22 with the electric motor 18, which moves the dispenser unit 12 while the piston actuator 20 remains stationary (see [link]). Figures 7A to 7B and Figures 8A to 8C ).like Figure 7A and Figure 7B As shown, individual pistons 34 are organized within the dispenser unit 12 and secured in place by piston retaining brackets 98. By keeping the dispenser unit 12 stationary, the individual pistons 34 can engage with the unit via a positioning piston tip capturing unit 64, such that the tip 36 of the desired piston 34 is located within a grooved recess 70 of the piston tip capturing unit 64. The shape of the grooved recess is configured to conform to the dimensions of the piston tip, which is characterized by a wide head 100 and a narrow neck 102. When each of the pistons 34 in the dispenser unit 12 is in its initial position ( Figure 3D The corresponding piston shaft 48 extends to prevent liquid from flowing out of the corresponding nozzle 30. When the dispenser unit moves, the head 100 of the corresponding piston tip 36 passes through the groove 70 of the piston tip capturing unit 64. When the dispenser unit is positioned such that the tip 36 of the desired piston (corresponding to the desired liquid to be dispensed) is within the groove 70, the movement of the displacement unit is stopped, so that when the piston tip capturing unit engages with the piston displacement cam 66, it moves vertically, thereby continuously pulling the piston tip 36 and retracting the corresponding piston shaft 48 (see...). Figure 3A ).

[0067] like Figures 8A to 8CAs shown, the dispenser unit 12 is repositioned by rotating the lead screw 22 clockwise or counterclockwise via the motor 18. The dispenser unit 12 is supported on the guide rail 29 and includes a threaded hole for receiving the lead screw 22. As the lead screw 22 rotates, its threaded circumference engages with the thread in the threaded hole of the dispenser unit 12, causing the dispenser unit to translate laterally, with the piston tip passing through a grooved recess in the piston tip capture unit, as discussed above. This allows the desired piston (i.e., the desired liquid for dispensing) to be positioned above the designated dispensing location on the article or membrane. This arrangement allows for rapid switching of the liquid used for dispensing via a single mechanism from any of the deposited fluids in the reservoir. Rotation of the lead screw allows for precise positioning of the droplets as the dispensing point moves relative to the platform 106, see [link to relevant documentation]. Figures 9A to 9C .

[0068] Now for reference Figure 10 The diagram illustrates a process 110 for dispensing material. At step 112, the material to be dispensed is defined. This involves filling syringes 40, which will be included in a plurality of reservoirs 14 of the dispenser unit 12, with the liquid material of interest. The syringes 40 are then placed in their respective reservoirs. Next, at step 114, the pressure of the syringes is set (e.g., by adjusting the position of the plunger 46). This ensures that liquid droplets are dispensed when the piston is activated. Then, at step 116, the printing frequency, droplet pattern, number of droplets, etc., are set. Although not shown in the figure, this involves programming control units connected to various motors 16, 18, 20 with the desired printing pattern. The control units preferably include a microprocessor and a memory coupled thereto, which stores the control program for this dispensing unit 10.

[0069] In one embodiment, the microprocessor and memory of the control unit are communicatively coupled via a bus or other communication mechanism for conveying information. In addition to program memory, the control unit may also include dynamic memory, such as random access memory (RAM) or other dynamic storage devices, coupled to the bus for storing information and instructions to be executed by the microprocessor. This dynamic memory can also be used to store temporary variables or other intermediate information during the execution of instructions to be executed by the microprocessor. The program memory may be read-only memory (ROM) or other static storage devices coupled to the bus for storing program instructions. Alternatively or in addition, storage devices such as magnetic disks or optical disks may be provided and coupled to the bus for storing information and instructions. The control unit may also include a display for displaying information to a user. The display, along with various input devices, including alphanumeric keypads and cursor control devices such as mice and / or trackpads, forms part of the user interface of the distribution system 10. Furthermore, one or more communication interfaces may be included to provide bidirectional data communication to and from the distribution unit. For example, a network interface including wired and / or wireless modems may be used to provide such communication.

[0070] In addition to limiting the printing frequency, the offset or eccentricity 118 of the piston displacement cam 66 is also limited. This serves to limit the piston stroke length, as discussed above. Checks can be performed to ensure that the nozzle is properly dispensing liquid 120 and that the printing operation 122 is running. The liquid material 124 is changed during the printing process as needed.

[0071] Now for reference Figure 11 One method of applying a material coating is to apply a thin and precise layer of rheological material onto a flexible membrane using a coating apparatus 130. In this illustration, the coating apparatus is shown as having an applicator 132, which may be similar to a reservoir containing an syringe (similar to those discussed above). In other embodiments, the following describes… Figure 13 and Figure 14 As described above, the coating apparatus 130 may include a complete material dispensing arrangement 10.

[0072] In the coating apparatus 130, two rollers 134 and 136, separated by a gap 138, define the thickness of the material layer applied to the film 140. For example... Figure 12As shown in detail, the gap width is defined by two tensioned microfilaments 142A and 142B held within the gap 138. The coater roller 136 is covered with another membrane 144 to ensure high surface quality. When changing between materials used for coating, the coater roller membrane 144 (along with the microfilaments 142A and 142B) can be advanced to prevent contamination. That is, for example, when switching to a different rheological material, the contact area of ​​the membrane covering the coater roller 136 can be adjusted relative to the gap (the coater roller membrane and the membrane across which the rheological material is applied are positioned). Similarly, if the coater roller membrane 144 is corroded or otherwise degraded, it can be advanced or replaced.

[0073] Under the control of one or more electric motors (not shown), a series of rollers advances the film to be coated through the coating area below the applicator 132. As shown, the film is unwound from the initial reel 146, wound through the coating area 150 below the applicator 132, and onto the take-up reel 148. The precise configuration of the path through which the film 140 travels will depend on the applied material and the properties of the film, and is not critical to the invention, except that the thickness of the applied material layer in the coating area 150 is determined by the gap width, which in turn depends on the thickness of the microfilaments 142A, 142B. Figure 12 As shown, the microfilament is suspended through gap 138 and supported on rollers or pins 152A, 152B. Rollers or pins 152A, 152B, rollers 134, 136, initial reel 146 and take-up reel 148 can be mounted on frame 149A.

[0074] As is known in the art, contact coating of thin films using two rollers presents challenges in achieving high surface quality and avoiding abrasive wear. The proposed system offers a unique solution to these problems with low operating costs. For example, the use of microfilaments allows for very precise control of coating thickness at low cost (by defining the gap width). Furthermore, because the microfilaments and film 144 can be easily rotated or exchanged when changing coating materials, cross-contamination of different materials is easily avoided. Moreover, using microfilaments to maintain the gap width allows coating with abrasive materials that minimize system wear. Because rollers 134 and 136 do not come into direct contact with the abrasive material, they are not as susceptible to wear as in conventional systems. In fact, the use of film 144 covering the coater roller 136 relaxes the requirements for roller roughness.

[0075] In one scenario, the gap width can be adjusted during rheological material dispensing by exchanging the microfilaments within the gap with different pairs (or other numbers) of microfilaments of different thicknesses. In other scenarios, the dispensing of the rheological material can be paused while exchanging the microfilaments with microfilaments of different thicknesses. The exchange of microfilaments may be accompanied by rotation or otherwise movement of the contact surface of the coater roller 144.

[0076] Now for reference Figure 13 and Figure 14 The use of the multi-material dispensing system 10 with the coating apparatus 130 is demonstrated. In these examples, the applicator 132 has been replaced with the multi-material dispensing system 10, and the membrane path has been adjusted accordingly to accommodate this unit. The coated membrane still passes through the coating region 150, where one or more liquid materials are applied to the membrane, and then through the gap 138, the thickness of which is defined by suspended microfilaments. The gap width determines the thickness of the applied layer. Using the multi-material dispensing system 10, the liquid material applied to the membrane 140 can be changed rapidly, as discussed above.

[0077] In this arrangement, it may not be necessary to change the piston stroke length because the thickness of the material layer is determined by the width of the gap 138. Therefore, the motor and other components for adjusting this dimension are not shown in the figure. However, in other embodiments, the above-described mechanism can be used to control the piston stroke length.

[0078] This coating system solves some of the inherent difficulties in coating films with multiple materials. The coating fluid is deposited onto the film to be coated. The coating is extended to a specific thickness by rollers 134 and 136. Roller 134, located on the coated side of the film, rotates freely, while roller 136 remains stationary during the coating process. Different materials can be deposited by changing the material in applicator 132 or by using a multi-material dispensing system 10. To prevent system contamination when switching from one coating to another, roller 136 is covered with a film 144, which is advanced to ensure the next coating is applied in a clean environment. The use of this film 144 also relaxes the tolerance for the roughness of roller 136 and makes it possible to coat corrosive materials, instead relying on the smoothness of the film to ensure uniform coating. This eliminates the need for expensive, high-precision machined rollers. The ability to periodically advance a second film also allows for the effective deposition of abrasive materials. In current systems, the second roller undergoes wear due to the abrasive nature of the coating material. In the proposed system, the film is advanced before wear becomes noticeable, thereby mitigating any loss of coating thickness accuracy.

[0079] Microfilaments 142A and 142B are used between two rollers 134 and 136 to define the gap between two films 140 and 144. During operation, a pair of electric motors or other actuators can be used to press the rollers 134 and 136 together with a specified and controlled force. This ensures a tight seal during the coating process, without the pressure from the microfilaments causing damage to the films, and eliminates the need for an expensive precision positioning control system. Replacing the microfilaments with those of different thicknesses and adjusting the force holding the rollers together adjusts the width of the gap 138 and allows for coatings of varying thicknesses.

[0080] Figure 15 A perspective view of the coating system is depicted, in which the gap between rollers 134 and 136 is defined using microfilaments of varying thickness (i.e., making the gap width adjustable). Multiple microfilament holders 166A, 166B, 166C, and 166D can be mounted on a frame 164. In the depicted embodiment, the number of microfilament holders is four, but this number may vary in other embodiments. The frame 164 can be secured to a system using one or more guide rails (in... Figure 15 In this example, the first guide rail is marked 162A, and the second guide rail is not visible. The guide rails are fixed to the guide rail holder 160. By sliding the frame 164 along the track, a microfilament holder (i.e., the selected microfilament holder) with a desired thickness can be positioned adjacent to the gap between rollers 134 and 136. In this example, microfilament holder 166B is the selected microfilament holder. By displacing the selected microfilament holder in a direction perpendicular to the track range, a microfilament with the desired thickness can be positioned between rollers 134 and 136.

[0081] exist Figure 15 In one embodiment, frame 149B separates the microfilament assembly 159 (including components 160, 162A, 164, 166A-D) from rollers 134 and 136, and slots may be present in frame 149B to allow the microfilaments to pass through frame 149B and enter the gap between rollers 134 and 136. A mirror image of the microfilament assembly 159 may exist on the back side of frame 149A (partially obscured by frame 149A in perspective view) to further define the gap between rollers 134 and 136.

[0082] If it is not yet obvious, then Figure 15 The frame 149A depicted in the text can correspond to Figures 11 to 14 The frame 149A is depicted in the figures. The shape of the frame may differ in the various figures, but the functions of the frames for the support rollers 134, 136, the initial reel 146, and the take-up reel 148 may be similar. Additionally, it should be noted that, for clarity, [details omitted]. Figure 15 The text depicts various components of the coating system (film 140, liquid reservoir 14, etc.), but it should be understood that... Figure 1 , Figures 2A to 2D , Figures 3A to 3D , Figure 4A , Figure 4B , Figures 5A to 5C , Figure 6 , Figures 7A to 7B , Figures 8A to 8C , Figures 9A to 9C as well as Figures 11 to 14 The various components described herein may exist Figure 15 In the coating system, this applies even if these components are not depicted.

[0083] Figure 16 A perspective view of the microfilament assembly 159 is depicted in more detail. As described above, the microfilament assembly 159 may include one or more microfilament holders 166A-D, which are mounted to a frame 164. The frame 164 may be secured to a first track using one or more guide rails 162A, 162B, which in turn may be secured to a guide rail holder 160. By sliding the frame 164 along the first track (e.g., by means of a motor not depicted), the plurality of microfilament holders 166A-166D may be translated in a direction parallel to the extent of the first track. Each microfilament holder may be displaced (e.g., by means of a motor not depicted) along a corresponding second track formed by guide rails 168A, 168B in a direction perpendicular to the extent of the first track. In this example, microfilament holder 166C is configured in an extended position, while microfilament holders 166A, 166B, and 166D are configured in a retracted position.

[0084] Figure 17 A perspective view of one of the microfilament retainers is depicted in more detail. The microfilament retainer 166 may include a retainer frame 170, rollers 174A, 174B, and filament supports 176A, 176B mounted to the retainer frame 170. One end of the microfilament 172 may be secured to roller 174A, and the other end of the microfilament 172 may be secured to roller 174B. The middle portion of the microfilament 172 may be supported by the filament supports 176A, 176B. Rollers 174A,

[0085] Rotation of 174B (e.g., clockwise or counterclockwise) around its respective axis of rotation allows adjustment of the tension in the microfilament 172. In practice, the microfilament 172 is fixed in a taut manner, such that the portion of the microfilament 172 between supports 176A and 176B has a linear form (i.e., resembling a one-dimensional line). Figure 17 The perspective view also shows the end portions of linear cavities 178A and 178B. Figure 16 , Figure 18The guide rails 168A and 168B depicted in the figure can extend through the linear cavities 178A and 178B, respectively.

[0086] Figure 18 A perspective view of rollers 134 and 136 is depicted, wherein the gap between rollers 134 and 136 is defined by two microfilament assemblies (each instance of a microfilament assembly is labeled 159). In operating the microfilament assemblies, frame 164 can be linearly moved along guides 162A and 162B to position a selected microfilament holder (i.e., a holder of microfilaments of the desired thickness) adjacent to rollers 134 and 136 (in this example, microfilament holder 166D). Next, the selected microfilament holder can be linearly translated along guides 168A and 168B to position portions of the selected microfilaments in close proximity to the surface of roller 134. Finally, roller 136 can be positioned (using roller support 180) such that the surface of roller 136 contacts the microfilaments already inserted into the gap between rollers 134 and 136, thereby creating a gap between rollers of the desired width. It should be understood that this process can be repeated (if necessary) to configure the gap between rollers 134 and 136 to have different widths. Subsequently, coatings of different thicknesses can be formed on membrane 140. For example, the coating process can begin with the dispensing of a first rheological material while the coating apparatus has a first gap width defined by a first pair (or other number) of microfilaments suspended through the gap, and then the dispensing of the first rheological material can be stopped to facilitate the dispensing of a second rheological material onto the surface of membrane 140, thereby adjusting the gap width by exchanging the first microfilaments for second microfilaments of a different thickness than the first microfilaments passing through the gap.

[0087] exist Figures 11 to 18 In the illustrated embodiment, microfilaments (e.g., 142A and 142B) are shown positioned between two rollers 134 and 136 and between two membranes 140 and 144. Therefore, the thickness of the microfilaments is used to define the gap 138. This is advantageous from the standpoint of providing very precise control over the gap width; however, the microfilaments may exert pressure on one or both of the membranes 140 and 144, resulting in abrasion and / or deformation of one or both membranes. To address this issue, modifications may be made in some embodiments of the invention. Figures 11 to 18The arrangement depicted in the figure is such that the width of the membrane 140 (on which the material layer is applied) is narrower than the spacing between the microfilaments 142A and 142B. In this arrangement, the microfilaments 142A and 142B will contact the roller 134 (e.g., near its edge), rather than the membrane 140. As a result, there is no pressure on the membrane 140 due to the microfilaments, thus reducing the risk of abrasion or deformation of the membrane 140. However, some control over the precision of the gap 138 is lost, because the gap width now depends on both the thickness of the microfilaments 142A and 142B and the thickness of the membrane 144. Another modified arrangement has a width of membrane 140 and a width of membrane 144, both of which are narrower than the spacing between the microfilaments 142A and 142B. In this arrangement, the microfilaments 142A and 142B contact the rollers 134 and 136 (e.g., near their respective edges), rather than the membrane 140 or membrane 144. As a result, there is no pressure on membrane 140 or membrane 144 due to the microfilaments, thus reducing the risk of wear or deformation of both membranes 140 and 144. However, some control over the precision of the gap 138 is lost, as the gap width now depends on both the thickness of the microfilaments 142A and 142B and the thickness of both membranes 140 and 144.

[0088] Figures 19A to 19C These different arrangements of microfilaments relative to rollers 134 and 136, and of membranes 140 and 144 engaged with rollers 134 and 136, are shown. Figure 19A In this configuration, microfilaments 142A and 142B are positioned between two rollers 134 and 136 and between two membranes 140 and 144. Therefore, the thickness of the microfilaments defines the gap 138. Figure 19B In this configuration, the width of the membrane 140 is narrower than the gap between the microfilaments 142A and 142B, thus the microfilaments contact the roller 134 outside the membrane 140 (e.g., near the edge of the roller 134). The width of the gap 138 is defined by both the thickness of the microfilaments 142A and 142B and the thickness of the membrane 144. Figure 19C In the process, the microfilaments contact the roller 134 outside the membrane 140 (e.g., near the edge of the roller 134) and the roller 136 outside the membrane 144 (e.g., near the edge of the roller 136). The width of the gap 138 is defined by both the thickness of the microfilaments 142A and 142B and the thickness of the membranes 140 and 144.

[0089] In various embodiments, the present invention then provides:

[0090] Example 1. A dispensing unit for dispensing liquid material, the unit comprising: a hollow reservoir configured to receive a syringe and including an elongated tube at one end of the reservoir, the tube providing a fluid path for liquid material dispensed from the syringe when supported in the reservoir and having an orifice near its end; a piston including a shaft disposed therein; and a bracket adapted to receive the tube of the reservoir such that the fluid path for the liquid material is oriented toward a nozzle disposed in the bracket, and adapted to receive the piston, the piston being oriented relative to the tube of the reservoir such that the shaft is aligned with the orifice in the tube and the nozzle, thereby allowing the shaft to be displaced toward the nozzle through the orifice.

[0091] Example 2. The distribution unit as described in Example 1, wherein the bracket includes a rail mount suitable for connection with the rail interface of the distributor system.

[0092] Example 3. The dispensing unit as described in Example 1, wherein the piston includes a tip located at the top of the piston; and an air connector positioned along the longitudinal length of the piston, the extension of the piston passing through the hollow shaft of the shaft and in fluid communication with the air connector.

[0093] Example 4. The dispensing unit as described in Example 1 further includes receiving the syringe within the reservoir, the syringe including a plunger and having a cap.

[0094] Example 5. A dispensing system comprising: one or more dispensing units as described in Example 1, the dispensing units being arranged to be laterally displaced along a length of the dispensing system defined by a lead screw; a first electric motor configured to drive the lead screw to displace the dispensing units along its length; and means for selectively actuating a piston of the dispensing unit to displace a corresponding axis of the piston of the dispensing unit relative to the nozzle of the bracket of the dispensing unit.

[0095] Example 6. A dispensing system as described in Example 5, wherein the means for selectively actuating the piston of the dispensing unit comprises: a piston tip capturing unit capable of translating within a piston capturing block parallel to the longitudinal axis of a corresponding piston in the piston of the dispensing unit; a second motor coupled to rotate a piston displacement shaft clockwise or counterclockwise, the piston displacement shaft having a piston displacement cam at one end thereof, wherein the piston tip capturing unit includes a cam recess for receiving the piston displacement cam and a slotted recess for receiving the tip of a corresponding shaft when disposed above the corresponding shaft in the piston, such that when the piston displacement cam rotates together with the piston displacement shaft, the piston tip capturing unit translates in a direction defined by the longitudinal axis of the piston, and any corresponding piston tip located at the top of the corresponding piston fixed within the slotted recess in the piston also translates along the longitudinal axis of the corresponding piston.

[0096] Example 7. The dispensing system as described in Example 6, wherein the end of the piston displacement shaft is offset from the rotation axis of the piston displacement shaft, and the piston displacement cam is elliptical in shape.

[0097] Example 8. The dispensing system as described in Example 6, wherein the piston tip capturing unit, which includes the cam recess, is fixed so as to remain stationary along an axis orthogonal to the longitudinal axis of the corresponding piston in the piston.

[0098] Example 9. The dispensing system as described in Example 6 further includes a third electric motor coupled to a rotating piston stroke shaft, wherein the piston stroke shaft has a piston stroke cam at one end, the piston stroke cam being positioned to engage a displaceable cam along the piston displacement shaft, the displaceable cam being adjacent to a spring-loaded wedge connected to the piston displacement cam, such that the displaceable cam forces the wedge open by movement of engaging the piston stroke cam, thereby causing the rotation center of the piston displacement cam to move radially away from the rotation axis of the piston displacement shaft.

[0099] Example 10. A method of dispensing material, the method comprising: filling one or more syringes with a liquid material of interest and subsequently placing each of the syringes into a corresponding reservoir of a plurality of reservoirs of a dispenser unit; setting a corresponding pressure of the syringes for dispensing droplets of the liquid material of interest when a corresponding piston shaft of a piston associated with the plurality of reservoirs is activated; programming a control unit of the dispenser unit with a desired print pattern of the liquid material of interest, the control unit being coupled to a plurality of actuators of the dispenser unit; setting an eccentricity of a piston displacement cam of the dispenser unit, the eccentricity defining a piston shaft stroke length of the piston; and performing a printing operation according to the desired print pattern, wherein during the printing operation, the actuators dispensing the liquid material from the reservoirs by displacing one of the corresponding piston shafts of the pistons associated with the plurality of reservoirs along its longitudinal length, thereby generating the droplets of the liquid material.

[0100] Example 11. The method as described in Example 10, wherein setting the corresponding pressure of the syringe includes adjusting the positioning of the corresponding plunger of the one or more syringes.

[0101] Example 12. The method as described in Example 10 further includes: changing the liquid material of interest as needed during the printing operation.

[0102] Example 13. The method as described in Example 10, wherein the displacement of each corresponding piston shaft is achieved by a rotating shaft in the actuator, one end of the shaft being offset from its axis of rotation, thereby forcing a piston tip capturing unit to displace in a direction parallel to the axis of the longitudinal length of the piston as the shaft rotates, the piston tip capturing unit capturing the top tip of the selected corresponding piston in a groove-shaped recess, the top tip being positioned within the groove-shaped recess as the piston tip capturing unit moves, thereby causing the shaft of the selected corresponding piston to also move.

[0103] Example 14. The method as described in Example 13, wherein the second actuator in the actuator displaces the plurality of reservoirs of the distribution unit along the length of the distribution unit between movements of the axis of each selected corresponding piston by rotating the lead screw clockwise or counterclockwise.

[0104] Example 15. The method as described in Example 14 further includes a third actuator in the actuator, the third actuator changing the piston shaft stroke length by changing the offset distance between the end of the shaft and its rotation axis.

[0105] Example 16. A coating apparatus comprising one or more dispensing units as described in Example 1, the dispensing units being arranged to apply rheological material from syringes housed within respective hollow reservoirs of the dispensing units onto a flexible film stretched between a pair of rollers, the flexible film being below respective nozzles of the dispensing units and passing through a gap defined by a pair of rollers of the coating apparatus, the gap defining the thickness of the rheological material layer applied to the film by being positioned thereafter the rheological material from the syringes is applied to a coating region of the film in the direction of film travel, and being held at a desired separation distance between the rollers by filaments suspended through the gap.

[0106] Example 17. The coating apparatus as described in Example 16 further includes a plurality of filament holders mounted on a frame slidably fixed to a first track formed by one or more guides fixed to the guide holders, such that a selected filament holder having filaments of desired thickness can be positioned adjacent to the gap between the pair of rollers.

[0107] Example 18. The coating apparatus as described in Example 17, wherein each microfilament holder is capable of displacement along a corresponding second track in a direction perpendicular to the first track.

[0108] Example 19. The coating apparatus as described in Example 18, wherein each filament holder includes a holder frame, a roller and a filament support mounted to the holder frame, one end of a corresponding filament of each filament holder is fixed to a corresponding first roller and the other end of the corresponding filament is fixed to a corresponding second roller, wherein the middle portion of the corresponding filament is supported by the filament support, such that the corresponding first roller and the second roller rotate about a corresponding axis of rotation to adjust the tension of the corresponding filament.

[0109] Example 20. The coating apparatus as described in Example 16, wherein the gap is defined by two microfilament assemblies, each microfilament assembly including a frame capable of linear translation along a guide rail to position a selected microfilament holder with a desired thickness adjacent to the surface of the roller.

[0110] Example 21. A coating apparatus comprising a dispensing unit arranged to apply a rheological material onto a flexible membrane drawn through a gap between a pair of rollers of the coating apparatus, the gap defining the thickness of the rheological material layer applied to the membrane by being positioned thereon after the rheological material is applied to a coating region of the membrane in the direction of membrane travel, and the gap having a width held at a desired separation distance between the rollers by filaments suspended through the gap.

[0111] Example 22. The coating apparatus as described in Example 21 further includes a plurality of filament holders mounted on a frame slidably fixed to a first track formed by one or more guides fixed to the guide holders, such that a selected filament holder having filaments of desired thickness can be positioned adjacent to the gap between the pair of rollers.

[0112] Example 23. The coating apparatus as described in Example 22, wherein each microfilament holder is capable of displacement along a corresponding second track in a direction perpendicular to the first track.

[0113] Example 24. The coating apparatus as described in Example 23, wherein each filament holder includes a holder frame, a roller and a filament support mounted to the holder frame, one end of a corresponding filament of each filament holder is fixed to a corresponding first roller and the other end of the corresponding filament is fixed to a corresponding second roller, wherein the middle portion of the corresponding filament is supported by the filament support, such that the corresponding first roller and the second roller rotate about a corresponding axis of rotation to adjust the tension of the corresponding filament.

[0114] Example 25. The coating apparatus as described in Example 21, wherein the gap width is defined by two microfilament assemblies, each microfilament assembly including a frame capable of linear translation along a guide rail to position a selected microfilament holder with a desired thickness adjacent to the surface of the roller.

[0115] Example 26. The coating apparatus as described in Example 21, wherein the microfilaments are suspended through the gap and in contact with the membrane.

[0116] Example 27. A coating apparatus as described in Example 21, wherein the microfilaments are suspended through the gap and contact one of the rollers instead of the film.

[0117] Example 28. The coating apparatus as described in Example 21, wherein...

[0118] The microfilaments are suspended through the gap and contact each of the pair of rollers, but not the membrane.

[0119] Example 29. The coating apparatus as described in Example 21, wherein the rheological material applied to the film is opposite to the second film across the gap.

[0120] Example 30. The coating apparatus as described in Example 29, wherein the microfilament is suspended through the gap and in contact with the membrane and the second membrane to which the rheological material is applied.

[0121] Example 31. A coating apparatus as described in Example 29, wherein the microfilaments are suspended through the gap and in contact with one of the rollers, rather than the film to which the rheological material is applied.

[0122] Example 32. The coating apparatus as described in Example 29, wherein the microfilaments are suspended through the gap and contact each of the pair of rollers rather than the membrane or the second membrane to which the rheological material is applied.

[0123] Example 33. A method of coating a film, comprising: dispensing a first rheological material onto the surface of the film while stretching a flexible film through a gap between a pair of rollers, the gap being positioned to define the thickness of the rheological material layer applied to the film after the rheological material is applied to a coating region of the film in the direction of film travel; and maintaining the gap at a certain width by positioning a first filament through the gap when the dispensing of the rheological material occurs.

[0124] Example 34. The method as described in Example 33, wherein the membrane to which the first rheological material is applied faces the second membrane across the gap, and further includes: adjusting the contact area of ​​the second membrane across the gap separated from the membrane to which the rheological material is applied.

[0125] Example 35. The method as described in Example 34 further includes: dispensing a second rheological material onto the surface of the flexible membrane after adjusting the contact area of ​​the second membrane.

[0126] Example 36. The method of Example 33 further includes: adjusting the width of the gap by exchanging the first microfilament with a second microfilament of a different thickness than the first microfilament passing through the gap during the dispensing of the first rheological material.

[0127] Example 37. The method as described in Example 36, wherein the membrane to which the first rheological material is applied faces the second membrane across the gap, and further includes: adjusting the contact area of ​​the second membrane across the gap separated from the membrane to which the rheological material is applied.

[0128] Example 38. The method as described in Example 33 further includes: pausing the dispensing of the first rheological material while exchanging the first microfilament for a second microfilament with a thickness different from that of the first microfilament passing through the gap.

[0129] Example 39. The method as described in Example 38, wherein the membrane to which the first rheological material is applied faces the second membrane across the gap, and further includes: adjusting the contact area of ​​the second membrane across the gap separated from the membrane to which the rheological material is applied.

[0130] Example 40. The method of Example 33 further includes: stopping the dispensing of the first rheological material to facilitate the dispensing of the second rheological material onto the surface of the membrane; and adjusting the width of the gap by replacing the first microfilament with a second microfilament of a different thickness than the first microfilament passing through the gap.

[0131] Therefore, systems and methods for dispensing liquid materials, for example, that can be used in applications such as coating flexible membranes, have been described, and in particular, such systems configured to dispense multiple liquid materials from multiple reservoirs.

Claims

1. A dispensing unit for dispensing liquid materials, the dispensing unit comprising: A hollow reservoir configured to receive a syringe and including an elongated tube at one end of the reservoir, the elongated tube providing a fluid path for the liquid material dispensed from the syringe when supported in the reservoir, and having an orifice near its end; A piston, the piston including a piston shaft disposed therein; as well as A bracket adapted to receive the elongated tube of the reservoir such that the fluid path of the liquid material is oriented toward a nozzle disposed in the bracket, and the bracket adapted to receive the piston such that the piston shaft is oriented relative to the elongated tube of the reservoir such that the piston shaft is aligned with the orifice and the nozzle in the elongated tube, thereby allowing the piston shaft to be displaced toward the nozzle through the orifice, wherein the piston includes a tip located at the top of the piston and an air tube positioned along the longitudinal length of the piston, an extension of the piston passing through the hollow shaft of the piston shaft and in fluid communication with the air tube.

2. The dispensing unit of claim 1, further comprising the syringe, wherein the syringe is received within the reservoir, and the syringe includes a plunger and a cap.

3. An allocation system, comprising: Lead screw; Multiple allocation units, each of the allocation units comprising: A hollow reservoir configured to receive a syringe and including an elongated tube at one end of the reservoir, the elongated tube providing a fluid path for liquid material dispensed from the syringe when supported in the reservoir, and having an orifice near its end; Piston, the piston including a piston shaft disposed therein; and A bracket, adapted to receive the elongated inlet tube of the reservoir such that the fluid path of the liquid material is oriented toward a nozzle disposed in the bracket, and the bracket is adapted to receive the piston, the piston being oriented relative to the elongated inlet tube of the reservoir such that the piston shaft is aligned with the orifice in the elongated inlet tube and the nozzle, thereby allowing the piston shaft to be displaced toward the nozzle through the orifice. The dispensing unit is arranged to be laterally displaced along the length of the dispensing system defined by the lead screw; A first electric motor, configured to drive the lead screw to displace the distribution unit along the length of the lead screw; and A means for selectively actuating the piston of the dispensing unit so as to displace the corresponding piston shaft of the dispensing unit relative to the corresponding nozzle of the corresponding bracket of the dispensing unit.

4. The distribution system as described in claim 3, The means for selectively actuating the piston of the dispensing unit includes a piston tip capturing unit and a second electric motor. The piston tip capturing unit is capable of translating within a piston capturing block parallel to the longitudinal axis of a corresponding piston in the dispensing unit. The second electric motor is coupled to rotate a piston displacement shaft clockwise or counterclockwise, and a piston displacement cam is provided at its end. The piston tip capturing unit includes a cam recess for receiving the piston displacement cam and a slotted recess for receiving the tip of a corresponding piston when positioned above a corresponding piston shaft. Thus, when the piston displacement cam rotates together with the piston displacement shaft, the piston tip capturing unit translates in a direction defined by the longitudinal axis of the corresponding piston, and any corresponding piston tip located at the top of the corresponding piston fixed within the slotted recess also translates along the longitudinal axis of the corresponding piston.

5. The dispensing system of claim 4, wherein the end of the piston displacement shaft is offset from the axis of rotation of the piston displacement shaft, and the piston displacement cam is elliptical in shape.

6. The dispensing system of claim 4, wherein the piston tip capturing unit comprising the cam recess remains stationary along an axis orthogonal to the longitudinal axis of the corresponding piston.

7. The dispensing system of claim 4, further comprising a third electric motor coupled to a rotating piston stroke shaft, wherein the piston stroke shaft has a piston stroke cam at one end thereof, the piston stroke cam being positioned to engage a displaceable cam along the piston displacement shaft, the displaceable cam being adjacent to a spring-loaded wedge connected to the piston displacement cam such that the displaceable cam forces the wedge open by movement of engagement with the piston stroke cam, thereby causing the rotation center of the piston displacement cam to move radially away from the rotation axis of the piston displacement shaft.

Images