TWI725879B - Surface-mounted deflection reducing spring plate with height stop base and side protruding cantilever - Google Patents

Abstract

A surface-mounted deflection reducing elastic sheet with a height stop base and a lateral cantilever includes: a height stop section; a suction side wall section that is bent from the side of the height stop section and extends a predetermined height; and one is bent from the inner edge, A bottom wall section that is approximately parallel to the height-stop shielding section with a predetermined interval; one is bent from the bottom wall section and extends parallel to the suction side wall section for welding to the mounting section of the circuit board; one is extended and bent by the height-stop shielding section , And the elastic arm section is arranged spaced apart from the bottom wall section, the elastic arm section includes a side protrusion extending from the side protrusion of the stop height shielding section, a downward bending part bent from the side protrusion toward the bottom wall section, and a downward bending The cantilever portion extends away from the bottom wall section and passes a predetermined interval to the cantilever portion that laterally exceeds the height-stop shielding section: and the end edge of the cantilever portion is turned away from the lower bend portion to form a bent support section extending toward the bottom wall section.

Description

Surface-mounted deflection reducing spring plate with height stop base and side protruding cantilever

The invention relates to a surface-mounted elastic sheet, in particular to a surface-mounted deflection reducing elastic sheet with a height stop base and a side protruding cantilever.

The shrapnel used in the electronics industry is made of metal materials such as phosphor bronze, stainless steel, etc., through the steps of stamping, bending, and heating and shaping, and then welded and fixed on a circuit board by surface-mount technology (SMT). The elastic restoring force of the metal material of the elastic sheet itself through bending is used as a conductive contact between circuit elements, transmitting signals, or providing a pressure buffer with mechanical elastic force. Due to the gradual miniaturization of electronic devices, the area of the solder pads planned on the circuit board is also required to be reduced.

As shown in Figure 1, when the elastic piece 9 is compressed in the past, the elastic arm 90 and the suction portion 92 tend to be compressed downward under the force on the one hand, and on the other hand, as shown by the dashed line, follow the arc direction toward the left rear Overturning, in addition to the original length L for soldering on the circuit board, it is necessary to reserve some additional stroke space for the elastic arm 90 and the suction part 92 to fall backwards, so the actual front and rear lengths occupied on the circuit board will be originally marked by L The elongation is L', and the elastic contact part of this spring structure will also be offset due to the rotation of the spring arm when it is pressed down, causing the position of the object above the figure to contact the spring to change. This situation is usually in the elastic arm stroke The longer the case, the more serious the deviation. Such problems can not be avoided even if the shrapnel is set to a side projecting shrapnel that is rotated at a ninety-degree angle.

In addition, in general, to protect the elastic arm from being damaged by excessive pressure, there is a structural design as shown in Fig. 2, which allows the left and right sides of the welding section 96 to bend upward to form two side walls 94 that are approximately parallel to each other. If the elastic arm 90 is pressed down excessively, part of the pressure is shared by the upright side wall 94 to increase the overall structural strength. However, the side wall 94 extending upward from the soldering section 96 still has the problem of being crooked and damaged when pressed, and after crooking, it will also interfere with other components on the left and right sides of the circuit board. Therefore, in this previous proposal, in addition to the original up and down bending of the elastic arm 90, there are also two left and right elastic legs 98 that extend downward and then bend after being bent sideways to ensure that the elastic arm 90 is pressed down. The structure is not easily damaged. Although this structure reduces the probability of damage to the elastic arm 90, considering the current common specifications of shrapnel, the so-called standard size of 0402 is generally the welding area of 0.04 inches in length and 0.02 inches in width, and the metric system is 1 mm long. , 0.5 mm wide range. It is very difficult to design the mold to bend at multiple complicated angles in such a small size, which not only affects the output efficiency of the product, but also reduces the product yield, which greatly increases the cost.

On the other hand, when the elastic arm tilts backwards and bends downward under pressure, the elastic arm changes the position of the upper contact point to cause deviation, which makes the corresponding antenna or other electronic components unable to be smoothly miniaturized. Similarly, even if the relationship between the welding direction and the feed-retracting direction of the dome is changed, the surface-mounted dome that shrinks inwardly will still have the problem of lateral pressure contact point offset.

Therefore, how to smoothly reduce the area occupied by the shrapnel on the circuit board; and during the adsorption process, it can provide an ideal adsorption side wall section, reduce the probability of poor adsorption and fall, and improve the output efficiency to facilitate automatic surface mounting; A good predetermined structure to provide good conductive contact, signal transmission, or mechanical elasticity to provide pressure buffering and support protection, especially when the elastic arm is elastically deformed by lateral pressure, the offset of the contact point position can be reduced, and This is the focus of this case.

An object of the present invention is to provide a surface-mounted deflection-reducing elastic sheet with a height stop base and a lateral cantilever. Through the ingenious structural design of the mounting section, the mounting area of the occupied circuit board can be smoothly reduced, which meets the needs of miniaturization.

Another object of the present invention is to provide a surface-mounted deflection reducing elastic sheet with a height stop base and a lateral cantilever with a stable suction side wall section structure, which reduces the falling probability during suction and improves the output efficiency of surface mounting.

Another object of the present invention is to provide a surface-mounted deflection-reducing elastic sheet with a height stop base and a lateral cantilever. The height stop base protects the structural safety of the elastic arm section when subjected to excessive lateral pressure and ensures product performance. Not easily deformed.

Another object of the present invention is to provide a surface-mounted deflection reducing elastic sheet with a height stop base and a lateral cantilever. The structure of the lateral cantilever compensates for the displacement of the elastic arm when the elastic arm is laterally fed and retracts under a force and reduces the offset And to ensure that the product contact points are located accurately.

According to the above-mentioned present case, a surface-mounted deflection-reducing elastic sheet with a height stop base and a lateral cantilever is for welding to a circuit board. The surface-mounted cantilever elastic sheet includes: a height stop section; The side of the section is bent to extend a suction side wall section of a predetermined height. The suction side wall section has an outer exposed edge connecting the height-stop shielding section, an inner edge opposite to the aforementioned outer exposed edge, and two connecting the outer exposed edge and the inner edge. Side edge; a bottom wall section that is bent from the above-mentioned inner edge, maintains a predetermined interval with the above-mentioned height-stop shielding section and extends approximately parallel to the above-mentioned height-stop shielding section; one is bent from the above-mentioned bottom wall section and is substantially parallel The suction side wall section extends for welding to the mounting section of the circuit board; an elastic arm section extending and bending from the height-stop shielding section and leaving a gap with the bottom wall section, the elastic arm section includes a by The side protrusion extending from the side protrusion of the height-stopping section, a downward bending portion bent and extending from the side protrusion toward the bottom wall section, and a downward bending portion extending away from the bottom wall section from the downward bending portion and passing through the above-mentioned downward bending portion. The predetermined interval between the height stop section and the bottom wall section to the cantilever part that laterally exceeds the height stop shield section: and the end edge of the cantilever part away from the downward bending part is reversely bent to form a bottom A bending support section extending from the wall section, wherein the shortest distance between the bending support section and the bottom wall section is smaller than the distance at which the top end of the cantilever portion protrudes from the height blocking section.

Through the surface-mounted deflection reduction spring plate with the height-stopping base and the lateral cantilever disclosed in this case, the force of the lateral cantilever rotates in opposite phases, which effectively compensates the deviation of the elastic arm when it is laterally fed and retracted under the force, so that The offset of the contact point is effectively reduced; and the height-stopping base formed by the height-stopping block section, the suction side wall section and the bottom wall section is jointly surrounded to support and protect the elastic arm section, so that the pressure-receiving part of the elastic arm section When the pressure displacement is lower than the aforementioned height stop section, it will not be easily deformed due to pressure; the ingenious design of the installation section makes it possible to miniaturize the shrapnel; especially the suction side wall section directly serves as a part of the height stop base When the suction nozzle is sucked and moved, there is no problem of large tolerances or pressure retreat, which is firmly supported. The suction drop rate is reduced, and the above problems are solved in one fell swoop.

1. 1’: Stop high-shielding section

12: bottom edge

2. 2’: Adsorption side wall section

22: Exposed Edge

24, 24’: inner edge

26, 26’: side edge

3. 3’: Bottom wall section

4. 4’: Installation section

5. 5’: Elastic arm section

52: lateral protrusion

54: Downturn

56: Cantilever

58: Strengthen ribs

6: Bending support section

7: Docking auxiliary installation section

70’: connecting section

72’: External expansion auxiliary installation section

9: shrapnel

90: Flexible arm

92: Adsorption part

94: side wall

96: Welding section

98: Spring Foot

560: top

Figure 1 is a schematic diagram of a conventional technique.

Fig. 2 is a three-dimensional schematic diagram of another conventional technique.

Fig. 3 is a perspective view of a first preferred embodiment of a surface-mounted deflection reducing elastic sheet with a height stop base and a lateral cantilever according to the present invention.

Fig. 4 is a front view of the embodiment of Fig. 3;

Fig. 5 is a right side view of the embodiment of Fig. 3.

Fig. 6 is a top view of the embodiment of Fig. 3;

Fig. 7 is a bottom perspective schematic view of the embodiment of Fig. 3, illustrating the position of the elastic arm section of the elastic sheet when no force is applied.

Fig. 8 is a bottom perspective schematic view of the embodiment of Fig. 3, illustrating the position of the elastic arm section of the elastic sheet when the elastic sheet deforms under pressure on the side.

FIG. 9 is a perspective view of the second preferred embodiment of the surface-mounted deflection reducing elastic sheet with the height-stopping base and the lateral cantilever of the present invention being welded and assembled to the circuit board.

Fig. 10 is a right side view of the embodiment of Fig. 9;

The technical content, features and effects of this case will be clearly presented in the following detailed description of the preferred embodiments with reference to the drawings. The same elements in each embodiment are marked with similar reference numerals.

In this case, the first preferred embodiment of the surface-mounted deflection-reducing elastic sheet with a height-stopping base and a lateral cantilever, as shown in Figures 3 to 8, includes a height-stopping shield that serves as the central position of the metal sheet connection in this example Section 1; a suction side wall section 2 with a predetermined depth bends from the side of the only height shielding section 1. For the convenience of description, the suction side wall section 2 is defined in the front side of the figure according to the direction of Fig. 3 and connected The edge of the stop height shielding section 1 is the exposed edge 22, the back side edge opposite to the exposed edge 22 is called the inner edge 24, and the connection between the exposed edge 22 and the inner edge 24 is defined as two side edges 26; one is defined by the inner edge 24 Bending, keeping a predetermined distance from the height-stop shielding section 1 and extending along the bottom wall section 3 substantially parallel to the height-stop shielding section 1; one is bent from the above-mentioned bottom wall section 3 and extends along the substantially parallel suction side wall section 2, The mounting section 4 for soldering to the circuit board; an elastic arm section 5 that is extended and bent from the height-stop shielding section 1 and is set with a gap between the bottom wall section 3 and the elastic arm section 5 includes a height-stop shielding section 5 Stalls 1 Side protrusions 52 extending from the side protrusions, a downward bend 54 extending from the side protrusion 52 toward the bottom wall section 3, and one extending from the downward bend 54 away from the bottom wall section 3, through the stop height shield The predetermined interval between the section 1 and the bottom wall section 3 to the cantilever portion 56 that laterally exceeds the height-stop shielding section 1: and the end edge of the cantilever portion 56 away from the downward bending portion 54 is reversely bent to form a bottom wall section 3 The extended bending support section 6, wherein the shortest distance between the bending support section 6 and the bottom wall section 3 is smaller than the distance by which the top end 560 of the cantilever portion 56 protrudes from the height blocking section 1. Since the elastic arm section 5 in this example has the same width as the side protrusion 52, the down-bent section 54 or the cantilever section 56, and the width corresponds to the height-stop shielding section 1, the overall structure is simple and the strength is stable.

In this example, the height-stop shielding section 1 is bent out of the bottom edge 12 away from the exposed edge 22 to form a docking auxiliary installation section 7, because the installation section 4 and the docking auxiliary installation section 7 in this example are coplanar and facing each other Extend to form a structure substantially parallel to the adsorption side wall section 2. Therefore, from the right side view, it can be found that the height stop shielding section 1, the suction side wall section 2, the bottom wall section 3, the installation section 4 and the docking auxiliary installation section 7, can surround a roughly closed rectangular structure as the height stop base , Even if the size of the whole shrapnel is reduced and the thickness of the metal sheet used for manufacturing the shrapnel becomes thinner, it can still effectively provide a strong structural support when the whole shrapnel is pressed down, making the miniaturization of the shrapnel possible. Even though the mounting section 4 and the docking auxiliary mounting section 7 complement each other at a fine interval in this example, and together form a soldering surface for soldering to the pad position on the circuit board, those skilled in the art can easily understand that the mounting section 4 It is not a necessary limitation to extend relative to the docking auxiliary installation section 7, even if only one bottom wall section 3 or the thickness of the wall surface of the height-stop shielding section 1 is left for welding to the circuit board, it will not hinder the implementation of this case.

Since the height-stop shielding section 1 and the bottom wall section 3 are approximately parallel, and a predetermined interval depth corresponding to the suction side wall section 2 is maintained therein, the cantilever portion 56 of the elastic arm section 5 can be closest to the bottom wall section by the downward bend 54 The edge of 3 is bent outwards, passing through this interval and bends in the outer direction to protrude beyond Stop the side surface of the shield section 1 and bend inward again to extend the bending support section 6. In this case, the tail part of the cantilever part 56 away from the downward bending part 54 is exposed to the side of the height stop section 1 in the unstressed state. Therefore, the side electronic components such as the antenna inside the mobile phone case (Figure (Not shown) when relatively close to the side pressure, it will first press against the part where the cantilever portion 56 and the bending support section 6 join, and force the elastic arm section 5 and the bending support section 6 to rotate in the counterclockwise direction of FIG. 8 The bending deformation is to enhance the structural strength of the connection part for the pressing contact. In this example, this part is formed with a section of upward convex stiffening ribs facing away from the bottom wall section 3, so this part is called the stiffening rib 58 ; Of course, those skilled in the art can easily understand that the reinforcing rib 58 is not necessarily limited to the protrusion shape, nor is it necessarily only one, and may even be only a single convex point, which will not hinder the implementation of the present invention.

As shown in Figures 7 and 8, we further discuss the lateral compression of the deflection-reducing shrapnel in this case. Because the axis that actually deforms due to rotation is the joint edge between the side protrusion 52 and the height stop section 1, the side protrusion 52 The right side is slightly bent upwards, and the downward bending part 54 is offset and twisted toward the right side of the figure, thus reducing the leftward deviation problem of the reinforcing rib 58 caused by the downward bending of the cantilever part 56, allowing the elastic arm disclosed in the present invention to During the deformation process under lateral pressure, the offset of the compressed contact part can be greatly reduced to almost negligible.

And because the shortest distance between the bending support section 6 and the bottom wall section 3 is less than the distance at which the top end 560 of the cantilever portion 56 protrudes from the height shielding section 1, after the reinforcing rib 58 is laterally compressed to a predetermined distance, the bending The support section 6 will first contact the bottom wall section 3 and provide an enhanced restoring force due to elastic deformation, avoiding permanent deformation caused by the elastic arm section 5 alone absorbing lateral pressure; then, when the degree of lateral pressure continues to increase, the elastic ribs The portion 58 will be compressed to be flush with the height of the exposed edge 22 of the height-stop shielding section 1 and the height-stop shielding section 2. At this time, the height-stop shielding section 1, the suction side wall section 2, the bottom wall section 3 and the installation The height stop base formed by section 4 will play a supporting role and protect the retracted elastic arm section 5 It will not be damaged. Due to the ingenious design of the side protrusion 52, not only does the cantilever 56 have to be slightly extended in the lateral direction, and the extension of this part will bring about twice the length of the entire elastic arm section 5, so that the total deformation caused by the side pressure is divided. Bearing by the longer metal sheet, the number of times the product can be repeatedly pressed is increased, and in the case of a total depth of only 1.6 millimeters (mm) of the shrapnel, the compressed reinforcing rib 58 can achieve a 0.7mm inward feeding and shrinking. At the same time, the lateral offset of the contact point can be ignored. Also because the elastic arm section 5 will not deviate or even tilt due to lateral pressure, it will not affect the surrounding components at all, effectively saving the occupied installation area, so that the other space on the circuit board can be used by other components flexibly. Meet the target demand of miniaturization.

At present, the metal shrapnel manufactured by automated stamping starts from a piece of metal sheet. First, the excess part is stamped and removed, leaving all the parts needed to make the bent shrapnel, as well as a tie to connect all materials, in the overall shrapnel After the flat sheet is gradually bent to form a single shrapnel, the tie is punched from the tie point, and the formed shrapnel is collected and subjected to subsequent processes such as electroplating or heat treatment. However, the required width of the strap must be at least 0.5mm, and it is usually symmetrical, that is, if the tie material points are designed in parallel, the side of the side should leave a tie material width of more than 1mm, which is for the shrapnel required by the industry. The demand for miniaturization will constitute a great limitation. Take the common 0402 specifications in the industry as an example. Generally, the so-called standard size of 0402 is the welding area of 0.04 inches in length and 0.02 inches in width. In the metric system, the range is 1mm long and 0.5mm wide. Inside, it is impossible to accommodate two binding points side by side with each other; even if the standard is relaxed and changed to 0603, which is common in the industry, it is only 1.5mm and 0.75mm long and wide distances, and it is also impossible to allow side-by-side binding. Point exists. Therefore, in this example, two side edges 26 are used as binding points. Even if it is a 0402 size shrapnel, as long as the depth direction is 0.5mm, it can be implemented smoothly, and the binding points are stretched on two opposite sides. Margin, the overall size of the shrapnel can therefore be sufficiently small According to the current technology, the produced shrapnel can reach a depth of only 1.6mm, and the feed shrinkage can reach 0.7mm, but there is almost no lateral deviation when under pressure, which greatly exceeds the existing products.

Considering the actual application, the side pressure surface mount shrapnel is not limited to being installed on the top of the circuit board. There are also some requirements to hollow out the circuit board and install the shrapnel on the notch of the circuit board to reduce the overall height of the circuit board. Please refer to FIG. 9 and FIG. 10 together, the second preferred embodiment of the present invention, in which the same parts as the previous embodiment will not be repeated here.

In this example, the circuit board is formed with a gap, and the inner edge 24' of the suction side wall section 2'is bent to extend out of the bottom wall section 3'. Since the bottom wall section 3'is bent outward to extend out of the mounting section 4', For soldering to the soldering pads on the circuit board, and the elastic arm section 5'bent out of the height stop section 1'will have a part of the height buried in the gap of the circuit board, making the width of the elastic arm section 5'larger than the bottom Wall section 3'; in addition, the two side edges 26' of the adsorption side wall section 2'in this example are also bent to extend two connecting sections 70', each connecting section 70' is approximately the same as the bottom wall section 3' The width is equal, and further bends away from the side edge 26' to each extend an externally-expanded auxiliary installation section 72' coplanar with the above-mentioned installation section 4', so that the welding and installation force can be jointly borne by the three welding points. Of course, as those skilled in the art can easily understand, as long as the peripheral structure is matched, even if there is only one external expansion auxiliary installation section or no external expansion auxiliary installation section at all, it will not hinder the implementation of this case.

Due to the design of the side protrusions of the present invention, the cantilever portion is correspondingly elongated, and the length of the elastic arm section is increased together, which effectively increases the range of plastic deformation, and is formed by the height stop section, the adsorption side wall section and the bottom wall section. The height stop base assists in support and guarantee to ensure that the product is not easily deformed; in addition, the suction side wall section itself is supported by the bottom wall section and the connecting sections on both sides, so it is not easy to deform. Even after miniaturization, it can also be used for machine adsorption to ensure surface mounting. It is not easy to fall during the adsorption process, which improves the output efficiency of surface installation; in addition, the special structure of the side protruding cantilever effectively compensates for the projectile The front and back displacement of the sex arm when it is laterally fed and retracted under a force to reduce the offset and ensure that during the use of the product, even if the elastic sheet is compressed and elastically retracted, the position of the contact point is still accurate and there will be no backwards problem, which substantially reduces the elastic sheet occupation The area is in line with the trend of miniaturization of electronic components.

The above are only the preferred embodiments of the present case, and any equivalent effects and other modifications according to the structure of the present case are within the scope of the present case.

1: Only high shielding section

12: bottom edge

2: Adsorption side wall section

22: Exposed Edge

24: inner edge

26: Side edge

3: bottom wall section

4: Installation section

5: Elastic arm section

52: lateral protrusion

54: Downturn

56: Cantilever

58: Strengthen ribs

6: Bending support section

7: Auxiliary installation section

Claims (4)

A surface-mounted deflection-reducing elastic sheet with a height stop base and a lateral cantilever is for welding to a circuit board. The surface-mounted cantilever elastic sheet includes: a height stop section; a side bent from the above height stop shield section A suction side wall section extending to a predetermined depth, the suction side wall section having an exposed edge connecting the height-stop shielding section, an inner edge opposite to the aforementioned exposed edge, and two side edges connecting the exposed edge and the inner edge; The inner edge is bent to maintain a predetermined interval from the height-stop shielding section and extends along a bottom wall section that is substantially parallel to the height-stop shielding section; one is bent from the bottom wall section and extends substantially parallel to the suction side wall section , For welding to the mounting section of the above-mentioned circuit board; an elastic arm section that is extended and bent from the above-mentioned height-stop shielding section, and is set with a gap between the above-mentioned bottom wall section, and the elastic arm section includes an elastic arm section that is covered by the above-mentioned height-stop The side protrusion extending from the side protrusion, a downward bending portion bent and extending from the side protrusion toward the bottom wall section, and a downward bending portion extending away from the bottom wall section from the above downward bending portion, and passing through the stop height shield The predetermined interval between the segment and the bottom wall segment to the cantilever portion that laterally exceeds the height-stop shielding segment: and the end edge of the cantilever portion away from the downward bending portion is reversely bent to form a cantilever portion extending toward the bottom wall segment The bending support section, wherein the shortest distance between the bending support section and the bottom wall section is less than the distance from the top end of the cantilever portion protruding from the height stop shielding section; One is bent and extends to a connecting section with the same width as the bottom wall section; and an externally-expanded auxiliary installation section that is bent from the connecting section away from the side edge and extends coplanar with the installation section. According to the first item of the scope of patent application, the surface-mounted deflection reducing elastic sheet, wherein the elastic arm section has a width larger than the bottom wall section and the connecting section. As described in the first item of the scope of patent application, the surface-mounted deflection reducing elastic sheet, wherein the cantilever portion has a width corresponding to the height stop section. As described in the first item of the scope of patent application, the surface-mounted deflection reducing elastic sheet, wherein the connection between the cantilever portion and the bending support section is formed with a reinforcing rib portion facing away from the bottom wall section.

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