Screen for solder paste brushing

Abstract

The application relates to the technical field of LED light source welding, in particular to a tin paste brushing steel mesh which comprises a substrate pad, a first window and a second window are arranged on the substrate pad, the first window and the second window are arranged at intervals, the first window and the second window are pentagons formed by cutting one angle of a rectangle and each has an inner recessed corner, and the inner recessed corner of the first window is arranged in correspondence with the inner recessed corner of the second window. The specific shape and size data of the window structure of the tin paste brushing steel mesh can effectively reduce LED light source welding defects, such as virtual welding, false welding, LED light source deviation, floating height and tin beads, and are favorable for improving product service life and aesthetic degree.

Description

Technical Field

[0001] This application relates to the field of LED light source welding technology, and in particular to a solder paste stencil. Background Technology

[0002] PCT3030 is a type of LED packaging product. PCT3030 LEDs are used by soldering the LED light source onto a PCB substrate. A stencil brush is used to print solder paste in batches, and a pick-and-place machine places the LEDs onto the solder paste-covered pads. The PCB substrate is then reflow soldered at high temperatures, making it a very efficient soldering method. However, some PCB substrates on the market have a solder pad opening ratio close to 1:1 with PCT 3030 LED packages. This stencil opening can lead to: 1. Insufficient solder paste, resulting in cold solder joints or false solder joints; 2. Excessive solder paste, causing the light source to shift, float, and have solder balls next to it, thus affecting the aesthetics.

[0003] Therefore, existing technologies have shortcomings and need to be improved. Summary of the Invention

[0004] This application provides a solder paste stencil to solve the above-mentioned problems.

[0005] In a first aspect, this application provides a solder paste stencil for assisting solder paste deposition so as to transfer solder paste onto a package pad, including a substrate pad, on which a first opening and a second opening are provided, the first opening and the second opening being spaced apart, the first opening and the second opening being a pentagon formed by cutting off a corner of a rectangle and each having a concave angle, the concave angle of the first opening and the concave angle of the second opening being correspondingly provided.

[0006] Optionally, the distance between the first window and the second window is 0.4 mm.

[0007] Optionally, the depth of the first window and the second window is 0.1 mm.

[0008] Optionally, the length of the first window is 1.9 mm, and the lengths of the top and bottom sides are the same and both are 0.68 mm.

[0009] Optionally, the side of the first window corresponds to its concave angle, and the distance between the vertex of the concave angle and the side of the first window is 0.4 mm.

[0010] Optionally, the vertex of the first concave angle of the window corresponds to the middle position of its side.

[0011] Optionally, the length of the second window is 1.9mm, and the lengths of the top and bottom sides are the same and are both 1.98mm.

[0012] Optionally, the side of the second window corresponds to its concave angle, and the distance between the vertex of its concave angle and the side of the second window is 1.13 mm.

[0013] Optionally, the vertex of the second concave angle of the window corresponds to the middle position of its side.

[0014] The technical solutions provided in this application have the following advantages compared with the prior art:

[0015] The embodiments of this application, by designing specific shape and size data of the window structure, can effectively reduce LED light source welding defects, such as poor soldering, false soldering, LED light source misalignment, floating, and the presence of solder balls that affect aesthetics, which is beneficial to improving product lifespan and aesthetics. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0019] Figure 1 This is a front view schematic diagram of a solder paste stencil provided in an embodiment of this application.

[0020] Figure 2 This is a cross-sectional schematic diagram of a solder paste stencil provided in an embodiment of this application.

[0021] Explanation of reference numerals in the attached figures:

[0022] 1. Substrate pad; 2. First window; 3. Second window; 4. Side of the first window; 5. Side of the second window. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0025] For ease of description, spatial relative terms may be used in the text to describe the relative position or movement of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "front," "back," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure undergoes a positional flip, orientation change, or change of motion, these directional indications will change accordingly. For instance, an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0026] To address the technical problems in the prior art, this application provides a solder paste stencil that can effectively reduce LED light source soldering defects, such as cold solder joints, false solder joints, LED light source misalignment, floating, and the presence of solder balls that affect aesthetics, by designing specific shape and size data of the window structure. This is beneficial to improving product lifespan and aesthetics.

[0027] Figure 1-2A solder paste stencil provided in this application embodiment is used to assist in solder paste deposition so as to transfer solder paste onto the packaging pad. It includes a substrate pad 1, on which a first window 2 and a second window 3 are formed. The first window 2 and the second window 3 are spaced apart. The first window 2 and the second window 3 are both pentagons formed by cutting off a corner of a rectangle and each has a concave angle. The concave angle of the first window 2 and the concave angle of the second window 3 are correspondingly set. The distance between the first window 2 and the second window 3 is 0.4 mm. The depth of the first window 2 and the second window 3 is 0.1 mm.

[0028] Furthermore, the length L1 of the first window 2 is 1.9mm, the length L2 of the upper and lower sides is the same and is 0.68mm, the side 4 of the first window corresponds to its concave angle α, and the distance between the vertex of the concave angle α and the side 4 of the first window is 0.4mm; wherein, the vertex of the concave angle α of the first window 2 corresponds to the middle position of its side 4.

[0029] Furthermore, the length L3 of the second window 3 is 1.9mm, the side lengths L4 of the upper and lower sides are the same and are both 1.98mm, the side 5 of the second window corresponds to its concave angle β, and the distance between the vertex of the concave angle β and the side 5 of the second window is 1.13mm; wherein, the vertex of the concave angle β of the second window 3 corresponds to the middle position of its side 5.

[0030] This utility model, by designing specific shape and size data for the window structure, can effectively reduce LED light source welding defects, such as incomplete soldering, false soldering, LED light source misalignment, floating, and the presence of solder balls that affect aesthetics, thereby improving product lifespan and appearance.

[0031] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0032] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0034] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0035] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0036] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0037] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Since these modifications and variations fall within the scope of the claims and their equivalents, this application also intends to include these modifications and variations.

[0038] The above description describes specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A solder paste stencil for assisting solder paste deposition in transferring solder paste onto package pads, characterized in that: The substrate includes a substrate pad, on which a first window and a second window are formed. The first window and the second window are spaced apart. The first window and the second window are both pentagons formed by cutting off a corner of a rectangle and each has a concave angle. The concave angle of the first window and the concave angle of the second window are correspondingly set.

2. The solder paste stencil according to claim 1, characterized in that: The distance between the first window and the second window is 0.4 mm.

3. The solder paste stencil according to claim 1, characterized in that: The depth of the first and second windows is 0.1 mm.

4. The solder paste stencil according to claim 1, characterized in that: The length of the first window is 1.9mm, and the lengths of the top and bottom sides are the same and are both 0.68mm.

5. The solder paste stencil according to claim 4, characterized in that: The side of the first window corresponds to its concave angle, and the distance between the vertex of the concave angle and the side of the first window is 0.4mm.

6. The solder paste stencil according to claim 5, characterized in that: The vertex of the first concave angle of the window corresponds to the middle position of its side.

7. The solder paste stencil according to claim 1, characterized in that: The length of the second window is 1.9mm, and the lengths of the top and bottom sides are the same, both being 1.98mm.

8. The solder paste stencil according to claim 7, characterized in that: The side of the second window corresponds to its concave angle, and the distance between the vertex of the concave angle and the side of the second window is 1.13mm.

9. The solder paste stencil according to claim 8, characterized in that: The vertex of the second concave angle corresponds to the middle position of its side.

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