Device for stretching screen for screen printing

Abstract

An apparatus (10) for stretching a screen for screen printing is provided. The device comprises a plurality of linear actuators (20) mounted on respective pedestals (30). The plurality of linear actuators comprise respective piston means (40) adapted to move from a retracted position (50) to an extended position (60) when actuated by a working fluid. The apparatus also includes one or more grippers (70) operably coupled to the respective piston devices. The one or more clamps are adapted to stretch the screen corresponding to the movement of the respective piston means, thereby stretching the screen printed screen. The web is adapted to be stretched on a frame (80) located on a base of a respective plurality of linear actuators.

Description

[0001] Earliest priority date

[0002] This application claims priority to a full patent application filed in India, having patent application number 202221021923, filed on April 12, 2022, and titled "Device for stretching a screen for screen printing". Technical Field

[0003] Embodiments of the present invention relate to the field of screen printing machines, and more particularly to an apparatus for stretching a screen for screen printing. Background Art

[0004] Screen printing is a printing technique in which a mesh is used to transfer ink or dye to a substrate, except in those areas where the screen printing template made of the mesh makes the ink or dye impermeable. The ink or dye may include solvent-based inks, UV-curable inks, discharge dyes, water-based dyes, and plastisol dyes. The mesh is placed on a frame to obtain a screen for screen printing. A scraper or squeegee moves over the screen, filling the open mesh holes with dye, and the reverse stroke causes the screen to momentarily contact the substrate along the contact line. This reverse stroke causes the dye to wet the substrate, and the dye is pulled out of the mesh holes when the screen rebounds after the scraper passes. In order to obtain a dye impression on the substrate, the mesh can be stretched on the frame. By using different screens and different colors, different color impressions can be obtained on the substrate.

[0005] The current apparatus for stretching the net on the frame is bulky and difficult to operate. In addition, due to accessibility issues, it is difficult to easily clamp the net to the apparatus for stretching the net and apply adhesive to the net once the net is stretched. In addition, the force to mass ratio of the apparatus is relatively small because the apparatus stretches the net during the compression stroke of the apparatus. In addition, the apparatus cannot provide uniform stretching force around the net. In addition, the apparatus lacks a measure to level the frame before stretching the net on the frame. In addition, the apparatus lacks features to prevent relative movement of the frame relative to the apparatus, thereby disrupting the stretching process. It is costly to modify the apparatus to obtain a higher force to mass ratio. In addition, the apparatus cannot prevent wrinkles from forming on the net when the net is stretched.

[0006] Therefore, an improved device for stretching a screen printing mesh is needed to solve the above problems. Summary of the invention

[0007] According to an embodiment of the present invention, a device for stretching a screen-printed mesh is provided. The device includes a plurality of linear actuators mounted on a corresponding base. The plurality of linear actuators include a corresponding piston device, which is suitable for moving from a retracted position to an extended position when actuated by a working fluid. The device also includes one or more clamps, which are operably connected to the corresponding piston device. The one or more clamps are suitable for stretching the mesh corresponding to the movement of the corresponding piston device, thereby stretching the screen-printed mesh. The mesh is suitable for being stretched on a frame, which is located on the base of the corresponding plurality of linear actuators.

[0008] In order to further illustrate the advantages and features of the present invention, the present invention will be described in more detail by referring to the specific embodiments of the present invention shown in the accompanying drawings. It should be understood that these drawings only depict typical embodiments of the present invention and are therefore not to be considered as limiting the scope. The present invention will be described and explained with additional features and details in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention will be described and explained with additional specificity and detail with reference to the accompanying drawings, in which:

[0010] Figure 1 is a schematic diagram of an apparatus for stretching a screen for screen printing according to an embodiment of the present invention; and

[0011] Figure 2 yes Figure 1 A schematic diagram of one embodiment of a system depicting a top view of an operational arrangement of multiple linear actuators and a frame according to an embodiment of the present invention.

[0012] Furthermore, those skilled in the art will appreciate that elements in the drawings are shown for simplicity only and may not necessarily be drawn to scale. Furthermore, one or more components of a device may have been represented in the drawings by conventional symbols with respect to its construction, and the drawings may show only those specific details relevant to understanding the embodiments of the invention so as not to obscure the drawings with details that would be apparent to those skilled in the art having the benefit of the description herein. DETAILED DESCRIPTION

[0013] In order to promote the understanding of the principle of the present invention, reference will now be made to the embodiments shown in the accompanying drawings, and specific language will be used to describe them. However, it should be understood that this is not meant to limit the scope of the present invention. Such changes and further modifications in the illustrated system that those skilled in the art would normally expect and such further applications of the principles of the present invention should be interpreted as being within the scope of the present invention.

[0014] The term "comprises" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process or method that includes a series of steps includes not only those steps, but may also include other steps not expressly listed or inherent to such process or method. Similarly, without further limitation, one or more devices or subsystems or elements or structures or parts preceded by "comprises..." does not exclude the presence of other devices, subsystems, elements, structures, parts, additional devices, additional subsystems, additional elements, additional structures or additional parts. The phrases "in one embodiment", "in another embodiment" and similar language appearing throughout this specification may all refer to the same embodiment, but do not necessarily all refer to the same embodiment.

[0015] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs.The systems, methods, and examples provided herein are illustrative only and not limiting.

[0016] In the following specification and claims, reference will be made to a number of terms which will be defined to have the following meanings: The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0017] Embodiments of the present invention relate to a device for stretching a screen-printed mesh. According to embodiments of the present invention, a device for stretching a screen-printed mesh is provided. The device comprises a plurality of linear actuators mounted on respective bases. The plurality of linear actuators comprise respective piston devices adapted to move from a retracted position to an extended position when actuated by a working fluid. The device further comprises one or more clamps operably connected to the respective piston devices. The one or more clamps are adapted to stretch the mesh in correspondence with the movement of the respective piston devices, thereby stretching the screen-printed mesh. The mesh is adapted to be stretched on a frame, which is located on the bases of the respective plurality of linear actuators.

[0018] Figure 1is a schematic diagram of a device (10) for stretching a screen printed mesh according to an embodiment of the present invention. The device (10) includes a plurality of linear actuators (20) mounted on a corresponding base (30). As used herein, a plurality of linear actuators (20) may be defined as a plurality of actuators that provide linear motion when actuated by a working fluid. In a specific embodiment, the plurality of linear actuators (20) may be coupled to the base (30) by one or more lugs (100). In one embodiment, the plurality of linear actuators (20) may include a cylinder (90). In some embodiments, the plurality of linear actuators (20) may include a hydraulic cylinder. In a specific embodiment, the plurality of linear actuators (20) may include a single-acting cylinder. In another embodiment, the plurality of linear actuators (20) are double-acting cylinders.

[0019] In addition, in a specific embodiment, each of the plurality of linear actuators (20) can be adapted to be actuated simultaneously. The plurality of linear actuators (20) include corresponding piston devices (40), which are adapted to move from a retracted position (50) to an extended position (60) when actuated by a working fluid. In one embodiment, the working fluid can include air. In a specific embodiment, the working fluid can include mineral oil. In one embodiment, the working fluid can be in a compressed state. In some embodiments, the working fluid for the plurality of linear actuators (20) can be provided by a centralized source. The device (10) also includes one or more clamps (70), which are operably connected to the corresponding piston devices (40). In one embodiment, the one or more clamps (70) can be adapted to clamp the net.

[0020] Furthermore, in a specific embodiment, one or more clamps (70) may include a corresponding fixed jaw and a corresponding movable jaw. In such embodiments, the movable jaw may be swung about the pivot point (110) by a handle (120) and a link (130) associated with the handle (120). In one embodiment, pivoting the handle (120) in a clockwise direction may cause the movable jaw to engage with the fixed jaw. In such embodiments, when the handle (120) is pivoted in a counterclockwise direction, the movable jaw may disengage from the fixed jaw. In one embodiment, one or more clamps (70) may include at least one of an eccentric clamp and a hinge clamp.

[0021] In addition, one or more clamps (70) are adapted to stretch the mesh corresponding to the movement of the corresponding piston device (40), thereby stretching the mesh for screen printing. In a specific embodiment, one or more clamps (70) may include a corrugated rubber surface to firmly attach the clamp (7d) to the mesh while stretching the mesh. In an embodiment, the mesh may include a mesh. In an exemplary embodiment, the number of meshes of the mesh may include, but is not limited to, 110, 156, 230, 38, 86, 305, etc.

[0022] Furthermore, in some embodiments, the mesh may be constructed of materials including, but not limited to, nylon, polyester, stainless steel, etc. In one embodiment, the piston device (40) may be adapted to provide a vibrating motion to prevent one or more wrinkles from forming in the mesh. In a specific embodiment, the piston device (40) may be adapted to move from the extended position (60) to the retracted position (50) by a reaction force provided by one or more springs. Figure 2 The plurality of linear actuators (20) and the frame ( Figure 2 , 80) operational arrangement.

[0023] Figure 2 yes Figure 1 A schematic diagram of an embodiment of a system of a plurality of linear actuators (20) and a frame is depicted in a top view of an operational arrangement according to an embodiment of the present invention. The net is adapted to be stretched on a frame (80) which is located on a base (30) of a corresponding plurality of linear actuators (20). In one embodiment, the frame (80) may be constructed of materials including, but not limited to, metal, wood, plastic, fiber, and the like. In a specific embodiment, the base (30) may include a height adjustment device adapted to level the frame (80) relative to the base (30). In such embodiments, the height adjustment device may include one or more fasteners adapted to adjust the gap between the frame (80) and the base (30). In some embodiments, the base (30) may include a locking mechanism adapted to prevent relative movement of the frame (80) relative to the base (30) by locking the frame (80) with the base (30).

[0024] In addition, the operation of the device is described in detail as follows. Initially, a plurality of linear actuators (20) can be positioned on a platform (140) in a rectangular arrangement. A frame (80) can be placed on a corresponding base (30) of the plurality of linear actuators (20). A height adjustment device can level the frame (80) relative to the base (30), and a locking mechanism can limit the relative movement of the frame (80) relative to the base (30). When the frame (80) is positioned on the base (30) of the corresponding plurality of linear actuators (20), one or more clamps (70) associated with the corresponding linear actuator (20) are disengaged by pivoting the corresponding handle (120) in a counterclockwise direction.

[0025] In addition, when one or more clamps (70) are disengaged, the net is introduced between the one or more clamps (70) and the corresponding handle (120) is pivoted in a clockwise direction to enable the one or more clamps (70) to fasten the net. When the one or more clamps (70) are engaged on the net, compressed air provided by the air source can be provided to the plurality of linear actuators (20). The plurality of linear actuators (20) can move from a retracted position (50) to an extended position (60) when actuated by the compressed air, thereby stretching the net on the frame (80). The net stretched on the frame (80) can be later fixed to the frame (80) by applying an adhesive.

[0026] The various embodiments of the apparatus for stretching a screen printing mesh described above have various advantages. The apparatus is compact and easy to operate. The compactness of the apparatus makes it easy to clamp the mesh to the apparatus. The compactness of the apparatus also makes it easy to apply adhesive to the mesh. Since the mesh is stretched during the expansion stroke of the apparatus, the force-to-mass ratio of the apparatus is very good. Simultaneous actuation of multiple linear actuators provides a uniform stretching force around the mesh.

[0027] In addition, the provision of a height adjustment device provides a means of leveling the frame relative to the base, thereby ensuring accuracy of screen printing. The provision of a locking mechanism also improves screen printing accuracy by preventing relative movement of the frame relative to the base. The ability of the piston device to provide a vibrating motion during stretching of the screen prevents the formation of one or more wrinkles in the screen, thereby improving the quality of the screen printing.

[0028] Those skilled in the art will appreciate that the above general description and the following detailed description are exemplary and explanatory of the present invention only and are not intended to limit the present invention. Although specific language has been used to describe the present invention, no limitation is intended to be generated thereby.

[0029] The accompanying drawings and the foregoing description provide examples of embodiments. It will be appreciated by those skilled in the art that one or more of the described elements may be well combined into a single functional element. Alternatively, certain elements may be divided into multiple functional elements. Elements in one embodiment may be added to another embodiment. For example, the order of the processes described herein may be changed and are not limited to the methods described herein. In addition, the actions of any flow chart do not need to be implemented in the order shown; nor do they necessarily need to perform all the actions. Similarly, actions that are not dependent on other actions may be performed in parallel with other actions. The scope of the embodiments is by no means limited by these specific examples.

Claims

1. A device (10) for stretching a screen for screen printing, comprising: a plurality of linear actuators (20) mounted on respective bases (30), wherein the plurality of linear actuators (20) include respective piston devices (40) adapted to move from a retracted position (50) to an extended position (60) when actuated by a working fluid; and one or more clamps (70) operably coupled to the respective piston means (40), wherein the one or more clamps (70) are adapted to stretch the web in response to movement of the respective piston means (40), thereby stretching the screen-printed web, The web is adapted to be stretched on a frame (80) which is located on the bases (30) of the corresponding plurality of linear actuators (20).

2. The device (10) according to claim 1, wherein: The plurality of linear actuators (20) include cylinders (90).

3. The device (10) according to claim 1, wherein: Each of the plurality of linear actuators (20) is adapted to be actuated simultaneously.

4. The device (10) according to claim 1, wherein: The piston means (40) is adapted to provide a vibrating motion to prevent the formation of one or more wrinkles in the web.

5. The device (10) according to claim 1, wherein: The piston arrangement (40) is adapted to be moved from the extended position (60) to the retracted position (50) by a reaction force provided by one or more springs.

6. The device (10) according to claim 1, wherein: The working fluid includes air.

7. The device (10) according to claim 1, wherein: The working fluid for the plurality of linear actuators (20) is provided from a centralized source.

8. The device (10) according to claim 1, wherein: The one or more clamps (70) include at least one of an eccentric clamp and a hinge clamp.

9. The device (10) according to claim 1, wherein: The base (30) includes a height adjustment device suitable for leveling the frame (80) relative to the base (30), wherein the height adjustment device includes one or more fasteners, and the one or more fasteners are suitable for adjusting the gap between the frame (80) and the base (30).

10. The device (10) according to claim 1, wherein: The base (30) includes a locking mechanism adapted to prevent relative movement of the frame (80) relative to the base (30) by locking the frame (80) with the base (30).

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