JP2021093345A - Press-fit terminal, substrate with press-fit terminal, and equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a maximum value of strain while increasing a contact load. A press-fit terminal 20 includes a tip portion 22, a press-fit portion 30, and a base end portion 26, and the width W4 of the press-fit portion 30 is larger than the maximum width W1 of the tip portion 22. The press-fit portion 30 includes two contact pieces 34, and the two contact pieces 34 include a first parallel portion 35, a second parallel portion 37, and an inclined portion 36, and the first parallel portion The outer width W2 of 35 is larger than the maximum width W1 of the tip portion 22, the outer width W4 of the second parallel portion 37 is larger than the outer width W2 of the first parallel portion 35, and the inclined portion 36 is the tip. The first parallel portion 35 on the portion side and the second parallel portion 37 on the base end portion side are connected, and the inclined portion 36 expands outward in the width direction toward the second parallel portion 37. [Selection diagram] Fig. 1

Description

The present disclosure relates to press-fit terminals, substrates with press-fit terminals, and devices.

Patent Document 1 discloses a press-fit terminal having a pair of elastic contact pieces arranged so as to face each other through an opening and located between a tip portion and a base portion to connect the two. In this press-fit terminal, the elastic contact piece projects in the same direction as the projecting direction of the elastic contact piece in at least one of the region including the boundary portion between the tip portion and the elastic contact piece and the region including the boundary portion between the base portion and the elastic contact piece. A stress distribution section is provided. In this press-fit terminal, it is described that the range of the stress receiving region is expanded by the stress dispersion portion and the stress (maximum value) becomes small.

JP-A-2018-63337 Japanese Unexamined Patent Publication No. 2004-127610 International Publication No. 2008/038331

For the press-fit terminal, it is desirable to increase the contact load and decrease the maximum strain value. The contact load is a load applied to the substrate from the press-fit terminal in a state where the press-fit terminal is inserted into the through hole of the substrate. The larger the contact load, the more difficult it is for the terminals to come off the board, and the more reliable the electrical connection between the terminals and the circuit on the board. Strain is a physical quantity that represents the amount of deformation of the shape of an object after it is deformed. For example, when the length before deformation is l and the length before deformation is Δl, the strain is represented by Δl / l. When the maximum value of distortion is small, it is possible to suppress the occurrence of cracks in the press-fit terminal when the press-fit terminal is deformed.

In the technique disclosed in Patent Document 1, the range of the stressed region is widened and the stress (maximum value) is reduced by the stress dispersion portion protruding in the same direction as the projecting direction of the elastic contact piece. However, depending on the size, it may be difficult to secure a sufficient space for providing the stress distribution portion in the press-fit terminal.

Therefore, it is desired to provide another technique capable of reducing the maximum value of strain while increasing the contact load.

Therefore, an object of the present disclosure is to reduce the maximum value of strain while increasing the contact load.

The press-fit terminal of the present disclosure is a press-fit terminal that is press-fitted into a through hole formed in a substrate, and includes a tip portion, a press-fit portion, and a base end portion that are sequentially connected to each other. The width of the tip portion is larger than the maximum width of the tip portion, the press-fit portion includes two contact pieces facing each other across an eye hole, and the two contact pieces are aligned with a first parallel portion arranged in a parallel posture. The outer width of the first parallel portion is larger than the maximum width of the tip portion, and the outer width of the second parallel portion is the first. The first parallel portion is larger than the outer width of the parallel portion, the first parallel portion is located closer to the tip portion side than the second parallel portion, and the inclined portion is the first parallel portion and the second parallel portion. The inclined portion is a press-fit terminal that expands outward in the width direction from the first parallel portion toward the second parallel portion.

According to the present disclosure, the contact load becomes large and the maximum value of strain becomes small.

FIG. 1 is a front view showing a press-fit terminal according to an embodiment. FIG. 2 is an explanatory diagram showing a state in which the press-fit terminal is being inserted into the through hole. FIG. 3 is a cross-sectional view showing a substrate with a press-fit terminal. FIG. 4 is a schematic view showing the device. FIG. 5 is a front view showing a press-fit terminal according to a modified example. FIG. 6 is a front view showing a press-fit terminal according to Example 1. FIG. 7 is a diagram showing an evaluation result of the press-fit terminal.

[Explanation of Embodiments of the present disclosure]
First, embodiments of the present disclosure will be listed and described.

The press-fit terminals of the present disclosure are as follows.

(1) A press-fit terminal that is press-fitted into a through hole formed in a substrate and includes a tip portion, a press-fit portion, and a base end portion that are sequentially connected, and the width of the press-fit portion is the same. Larger than the maximum width of the tip portion, the press-fit portion includes two contact pieces facing each other across an eye hole, and the two contact pieces are arranged in a parallel posture with a first parallel portion arranged in a parallel posture. The outer width of the first parallel portion is larger than the maximum width of the tip portion, and the outer width of the second parallel portion is the outer width of the first parallel portion, including the second parallel portion and the inclined portion. The first parallel portion is located closer to the tip portion side than the second parallel portion, and the inclined portion connects the first parallel portion and the second parallel portion. The inclined portion is a press-fit terminal that expands outward in the width direction from the first parallel portion toward the second parallel portion.

According to this press-fit terminal, it is possible to design to keep the contact load larger than that of the conventional product. Even in this case, the maximum value of distortion can be made smaller than that of the conventional product.

The reason why the maximum value of distortion can be made smaller than that of the conventional product is as follows. The outer width dimension of the two contact pieces increases toward the second parallel portion in the inclined portion. Therefore, at a position away from the tip of the eye hole, the two contact pieces come into contact with the inner surface of the through hole, and the two contact pieces can be deformed. As a result, the two contact pieces are likely to be deformed not only at the tip-side connecting portion but also at the connecting portion between the first parallel portion and the inclined portion. As a result, the deformation of the two contact pieces is dispersed in a plurality of places, and the maximum value of distortion can be made smaller than that of the conventional product.

(2) In the press-fit terminal of (1), the inner width of the second parallel portion may be larger than the inner width of the first parallel portion. The second parallel portion is also easily deformed, and the deformed portions of the two contact pieces are more dispersed.

(3) The press-fit terminal according to (1) or (2), wherein the total length of the eye hole is L, and the length from the tip of the eye hole to the portion of the eye hole that maintains the same inner width in the first parallel portion. When L1, the L1 may be 30% or more and 50% or less with respect to the L. In this range, the contact load tends to increase and the maximum strain tends to decrease.

(4) The press-fit terminal according to any one of (1) to (3), wherein the width of the first parallel portion of the two contact pieces is the first of the two contact pieces. It may be smaller than the width in the two parallel portions. In this case, since the portion of the two contact pieces in the first parallel portion is relatively narrow, the contact pieces can be easily deformed.

(5) The press-fit terminal according to any one of (1) to (4), and the thickness of the press-fit terminal may be 0.3 mm or more and 0.5 mm or less. When the thickness of the press-fit terminal is as thin as 0.5 mm or less, the through hole becomes small, and it becomes difficult to secure a sufficient space for providing the stress distribution portion. In such a case, it is possible to reduce the maximum value of strain while increasing the contact load.

(6) A press-fit terminal according to any one of (1) to (5), wherein the two contact pieces further include a third parallel portion arranged in a parallel posture, and the third parallel portion is , The base end portion is located closer to the second parallel portion, and the outer width of the third parallel portion may be smaller than the outer width of the second parallel portion. In this case, when the press-fit terminal is inserted into the through hole, the two contact pieces are based on the second parallel portion even in the portion where the second parallel portion in the longitudinal intermediate portion is connected to the first parallel portion on the tip side. Even the portion connected to the third parallel portion on the end side is easily deformed. As a result, the second parallel portion is easily deformed so as to reduce the width while maintaining the parallel posture. As a result, the outer edge of the second parallel portion is easily maintained in a state of extending along the axial direction of the through hole, and the contact region between the two contact pieces and the inner surface of the through hole is increased.

(7) In the press-fit terminal of (6), the outer width of the third parallel portion may be larger than the outer width of the first parallel portion. Since the outer width of the third parallel portion is larger than the outer width of the first parallel portion, the press-fit terminal easily contacts the inner surface of the through hole even in the third parallel portion. As a result, the contact area between the two contact pieces and the inner surface of the through hole becomes large.

(8) The substrate with a press-fit terminal of the present disclosure relates to a substrate in which a through hole is formed and any one of the above (1) to (7) in which the press-fit portion is press-fitted into the through hole. A substrate with a press-fit terminal, which comprises a press-fit terminal, the outer width of the first parallel portion is smaller than the diameter of the through hole, and the second parallel portion is in contact with the inner peripheral surface of the through hole. Is. In this case, when the press-fit terminal is inserted into the through hole, the second parallel portion can be deformed so that the two contact pieces narrow the width.

(9) The substrate with a press-fit terminal of the present disclosure relates to a substrate on which a through hole is formed and any one of the above (1) to (7) in which the press-fit portion is press-fitted into the through hole. A substrate with a press-fit terminal, which comprises a press-fit terminal, and in a state where the inner portions of the two contact pieces are in contact with each other, the outer portion of the two contact pieces is in contact with the inner peripheral surface of the through hole. Is. In this case, the inner portions of the two contact pieces come into contact with each other while the press-fit portion is press-fitted into the through hole. This prevents the two contact pieces from being further deformed inward. Therefore, the outer portion of the two contact pieces is easily kept in a state of being strongly pressed against the inner peripheral surface of the through hole, and the contact load is easily kept large.

(10) The apparatus of the present disclosure is an apparatus including the substrate with the press-fit terminal according to the above (8) or (9) and a case for accommodating the press-fit terminal. In this case, in the device, the contact load of the press-fit terminal becomes large and the maximum value of distortion becomes small.

[Details of Embodiments of the present disclosure]
Specific examples of the press-fit terminal, the substrate with the press-fit terminal, and the device of the present disclosure will be described below with reference to the drawings. It should be noted that the present disclosure is not limited to these examples, and is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

The press-fit terminals of the present disclosure are meaningful in the following background. That is, for the press-fit terminal, it is required to increase the contact load and reduce the strain. The contact load is intended to be the load applied to the substrate from the press-fit terminal when the press-fit terminal is inserted into the through hole. The larger the contact load, the more difficult it is for the terminals to come off the substrate, and the more reliable the electrical connection between the terminals and the substrate is. The strain is intended to be the elongation strain of the outermost surface of the press-fit terminal (the amount of elongation with respect to the original shape, the maximum strain when a mesh-like partition is set on the outermost surface in analysis). If this distortion is large, there is a disadvantage that the terminals are cracked.

In general, increasing the contact load and reducing the strain are difficult to achieve at the same time. For example, if the press-fit terminal is greatly deformed by inserting the press-fit terminal into the through hole by devising the shape of the press-fit terminal, selecting a material, etc., the contact load becomes large, but the distortion also becomes large. Will end up. On the contrary, for example, if the press-fit terminal is not significantly deformed by inserting the press-fit terminal into the through hole, the distortion is reduced but the load is also reduced.

For press-fit terminals and the like having a thickness of 0.6 mm, as disclosed in Patent Document 1, by providing a mountain-shaped stress distribution portion, it is possible to increase the contact load and reduce the strain. Is. Patent Document 1 is a device in which a stress distribution portion is provided in a portion where the strain is the largest, in view of the fact that the strain of the press-fit terminal becomes the largest around the edge of the eye hole and the like.

By the way, as described above, there is an increasing demand for press-fit terminals having a thickness of 0.5 mm or less, particularly a thickness of 0.4 mm. Therefore, it was examined whether the device of Patent Document 1 could be applied to the press-fit terminal having a thickness of 0.4 mm. However, due to dimensional reasons, it has been difficult to provide a stress distribution portion for a press-fit terminal having a thickness of 0.4 mm. This is because, in the press-fit terminal having a thickness of 0.4 mm, the size of the protrusion of the press-fit terminal that is press-fitted into the through hole is small, and the width of the eye hole is also small, so that a stress distribution portion is provided. This is because it is difficult to secure the space for.

Therefore, in the present disclosure, instead of the stress distribution portion, a shape capable of alleviating strain and suppressing reduction of contact load has been studied, and as a result, the shape of the press-fit terminal shown below has been conceived.

[Embodiment]
Hereinafter, the press-fit terminal and the substrate with the press-fit terminal according to the embodiment will be described. FIG. 1 is a front view showing the press-fit terminal 20. FIG. 1 shows a cross section of the substrate 12 into which the press-fit terminal 20 is inserted. FIG. 2 is an explanatory view showing a state in which the press-fit portion 30 is being inserted into the through hole 13. FIG. 3 is a cross-sectional view showing a substrate 10 with a press-fit terminal.

The press-fit terminal 20 is a terminal that is press-fitted into the through hole 13 formed in the substrate 12. Here, the substrate 12 is formed of an insulating plate such as a glass epoxy plate. Through holes 13 penetrating the front and back surfaces are formed on the substrate 12. The through hole 13 is a circular hole. The through hole 13 may be a square hole or the like. A conductive layer 13f made of a metal such as copper is formed on the inner surface of the through hole 13. With the press-fit terminal 20 press-fitted into the through hole 13, the press-fit terminal 20 comes into contact with the conductive layer 13f and is electrically connected to the conductive layer 13f.

The press-fit terminal 20 is formed of a metal such as copper or a copper alloy. The press-fit terminal 20 may be formed by, for example, pressing a metal plate. The surface of the press-fit terminal 20 may be plated with tin, a tin alloy, or the like.

The press-fit terminal 20 includes a tip portion 22, a press-fit portion 30, and a base end portion 26. In the press-fit terminal 20, the tip portion 22, the press-fit portion 30, and the base end portion 26 are connected in this order. The tip portion 22 is a portion that is first inserted into the through hole 13 when the press-fit terminal 20 is inserted into the through hole 13. The base end portion 26 is a portion in which a portion serving as an electrical connection destination of the conductive layer 13f on the through hole 13 side is connected. In the example shown in FIG. 4 to be described later, the base end portion 26 is connected to the connector terminal portion 54.

The press-fit portion 30 is a portion provided between the tip end portion 22 and the base end portion 26. The width W4 (here, the maximum width) of the press-fit portion 30 is larger than the maximum width W1 of the tip portion 22, and further larger than the diameter φ of the through hole 13. Therefore, the press-fit portion 30 can come into contact with the inner peripheral surface of the through hole 13. The press-fit portion 30 may be grasped as a portion for obtaining electrical contact with the conductive layer 13f by maintaining a contact state with the inner peripheral surface of the through hole 13.

More specifically, the press-fit terminal 20 is formed in an elongated plate shape extending linearly as a whole.

The tip portion 22 includes a rectangular plate-shaped portion having a continuous portion having the same width. The edges on both sides of this rectangular plate are parallel to each other. The width W1 of the tip portion 22 is smaller than the diameter (diameter) φ of the through hole 13. At the tip of the rectangular plate-shaped portion of the tip 22 (the end opposite to the press-fit portion 30), the tip 22a that gradually narrows toward the tip is provided. Due to the presence of the most advanced portion 22a, the press-fit terminal 20 is easily inserted into the through hole 13. The tip portion 22 can be inserted into the through hole 13 with a gap with respect to the inner peripheral surface of the through hole 13.

The base end portion 26 includes a rectangular plate-shaped portion having a continuous portion having the same width. The edges on both sides of this rectangular plate are parallel to each other. The width of the base end portion 26 is smaller than the width W4 of the press fit portion 30. Here, the width of the base end portion 26 is the same as the maximum width W1 of the tip end portion 22. The width of the base end portion 26 may be different from the width of the tip end portion 22.

The press-fit portion 30 is provided between the tip end portion 22 and the base end portion 26. The press-fit portion 30 includes two contact pieces 34 facing each other across the eye hole 31. The eye hole 31 is a hole elongated in the direction connecting the tip end portion 22 and the base end portion 26. Specific examples of the shape of the eye hole 31 include a perfect circle, an ellipse, an oval shape, a cube, and a rectangular parallelepiped. The eye hole 31 is preferably elongated in the direction in which the press-fit terminal is inserted. The contact piece 34 is formed in the shape of an elongated plate. One end of the two contact pieces 34 is connected to the tip 22. The other end of the two contact pieces 34 is connected to the base end portion 26.

The two contact pieces 34 include a first parallel portion 35, a second parallel portion 37, and an inclined portion 36.

The first parallel portion 35 is a portion in which a part of the two contact pieces 34 is arranged in a parallel posture. More specifically, the first parallel portion 35 is a portion of the two contact pieces 34 in which a part closer to the tip portion 22 is lined up in a parallel posture along the direction connecting the tip portion 22 and the base end portion 26. is there.

The second parallel portion 37 is a portion in which the other part of the two contact pieces 34 is arranged in a parallel posture. More specifically, in the second parallel portion 37, a part of the two contact pieces 34 near the base end portion 26 is arranged in a parallel posture along the direction connecting the tip end portion 22 and the base end portion 26. Is.

The inclined portion 36 is a portion in which the other part of the two contact pieces 34 is inclined. More specifically, in the inclined portion 36, the portion of the two contact pieces 34 between the first parallel portion 35 and the second parallel portion 37 is in the direction connecting the tip portion 22 and the base end portion 26. It is a part that is inclined with respect to it.

The outer width W2 of the first parallel portion 35 is larger than the maximum width W1 of the tip portion 22. Here, the outer width W2 of the first parallel portion 35 is smaller than the diameter φ of the through hole 13. The outer width W2 of the first parallel portion 35 is not limited to a shape smaller than the diameter φ of the through hole 13, and may be a shape larger than the diameter φ of the through hole 13.

The outer width W4 of the second parallel portion 37 is larger than the outer width W2 of the first parallel portion 35. Therefore, the second parallel portion 37 projects outward from the first parallel portion 35. The outer width W4 is larger than the diameter φ of the through hole 13. When the press-fit portion 30 is inserted into the through hole 13, the second parallel portion 37 comes into contact with the inner peripheral surface of the through hole 13 and deforms inward.

The inner width V2 of the second parallel portion 37 is preferably larger than the inner width V1 of the first parallel portion 35. In this case, the second parallel portion 37 can be deformed more inward than the first parallel portion 35. It is also grasped that the inner width V2 of the second parallel portion 37 is the hole width V2 in the second parallel portion 37 of the eye hole 31. It is also understood that the inner width V1 of the first parallel portion 35 is the hole width V1 in the first parallel portion 35 of the eye holes 31. In other words, the width of the eye hole 31 is preferably larger in the second parallel portion 37 than in the first parallel portion 35. The shape of the eye hole may be, for example, a race track shape. In this case, the inner width V1 and the inner width V2 are the same.

The first parallel portion 35 is located closer to the tip end portion than the second parallel portion 37. Here, of the two contact pieces 34, the portion closer to the tip portion 22 includes two square plate-shaped portions extending in a parallel posture in the direction connecting the tip end portion 22 and the base end portion 26. These two square plate-shaped portions are the first parallel portion 35. The outer edges of each of the two square plate-shaped portions are lined up in a parallel position. The inner edges of each of the two square plate parts are also lined up in a parallel position.

In the present embodiment, the two square plate-shaped portions in the first parallel portion 35 are connected to the tip portion 22 via the tip side inclined portion 38. Here, of the two contact pieces 34, the portion connected to the tip portion 22 is the tip end side inclined portion 38. The tip end side inclined portion 38 extends from the first parallel portion 35 toward the tip end portion 22 side so as to gradually become narrower. The outer edges of the tip-side inclined portion 38 are formed so as to gradually narrow from the outer edges of the first parallel portion 35 toward the outer edges of the tip portion 22. Both outer edges of the tip-side inclined portion 38 may have a curved shape, a shape in which a plurality of straight lines are connected at an angle, or a composite shape thereof. Here, both outer edges of the tip-side inclined portion 38 have a shape in which curves are continuous at both ends of a straight line in the middle portion in the length direction. The inner edge of the tip end side inclined portion 38 is formed by the edge of the tip end portion 22 side of the eye hole 31. Here, the edge of the end of the eye hole 31 on the tip 22 side is formed in a curved shape such as an arc shape, but a plurality of straight lines may be connected at an angle, or they may be connected. It may be a composite shape of.

The inclined portion 36 is a portion of the two contact pieces 34 that connects the first parallel portion 35 and the second parallel portion 37. The inclined portion 36 is formed so as to expand outward in the width direction from the first parallel portion 35 toward the second parallel portion 37. Here, of the two contact pieces 34, the portion closer to the base end portion 26 includes two square plate-shaped portions extending in a parallel posture in the direction connecting the tip end portion 22 and the base end portion 26. These two square plate-shaped portions are the second parallel portions 37. The outer edges of each of the two square plate-shaped portions are lined up in a parallel position. The inner edges of each of the two square plate parts are also lined up in a parallel position.

The inclined portion 36 includes two plate-shaped portions connecting the two square plate-shaped portions in the second parallel portion 37 and the two square plate-shaped portions in the first parallel portion 35. That is, of the two contact pieces 34, the portion between the first parallel portion 35 and the second parallel portion 37 is the inclined portion 36. The two plate-shaped portions in the inclined portion 36 are located toward the center in the width direction from each of the two square plate-shaped portions in the second parallel portion 37 toward each of the two square plate-shaped portions in the first parallel portion 35. It extends to narrow.

The outer edges of the inclined portion 36 extend gradually toward the center side in the width direction from the outer edges of the second parallel portion 37 toward the outer edges of the first parallel portion 35. The outer edges of the inclined portion 36 may have a curved shape, a shape in which a plurality of straight lines are connected at an angle, or a composite shape thereof. Here, both outer edges of the inclined portion have a shape in which curves are continuous at both ends of a linear portion in the middle portion in the length direction. The inner edge of the inclined portion 36 is formed by the edge of the intermediate portion in the length direction of the eye hole 31. As described above, the width of the eye hole 31 is larger in the second parallel portion 37 than in the first parallel portion 35. According to this difference in width, the inner edge of the inclined portion 36 gradually faces the center side in the width direction from both inner edges of the second parallel portion 37 toward both inner edges of the first parallel portion 35. Extends to. Both inner edges of the inclined portion 36 may have a curved shape, a shape in which a plurality of straight lines are connected at an angle, or a composite shape thereof. Here, both inner edges of the inclined portion 36 have a shape in which curves are continuous at both ends of a straight portion in the middle portion in the length direction. In particular, the portion from both inner edges of the inclined portion 36 to the inner edge of the second parallel portion 37 is formed in a curved shape that is convex outward.

Further, in the present embodiment, the two square plate-shaped portions in the second parallel portion 37 are connected to the proximal end portion 26 via the proximal end side inclined portion 39. Here, of the two contact pieces 34, the portion connected to the proximal end portion 26 is the proximal end side inclined portion 39. The base end side inclined portion 39 extends from the second parallel portion 37 toward the base end portion 26 side so as to gradually become narrower. The outer edges of the base end side inclined portion 39 are formed so as to gradually narrow from both outer edges of the second parallel portion 37 toward both outer edges of the base end portion 26. Both outer edges of the base end side inclined portion 39 may have a curved shape, a shape in which a plurality of straight lines are connected at an angle, or a composite shape thereof. Here, both outer edges of the base end side inclined portion 39 have a shape in which curves are continuous at both ends of a straight line portion in the middle portion in the length direction. The inner edge of the base end side inclined portion 39 is formed by the edge of the end portion of the eye hole 31 on the base end portion 26 side. Here, the edge of the end portion of the eye hole 31 on the base end portion 26 side is formed in a curved shape such as an arc shape, but a plurality of straight lines may be connected at an angle. It may be a composite shape thereof.

All or part of the edge of the press-fit terminal 20 may be chamfered. For example, the edges of the first parallel portion 35, the second parallel portion 37, the base end portion 26, the tip end portion 22, and the like may be chamfered.

The press-fit terminal 20 configured as described above is inserted into the through hole 13. Here, the width W1 of the tip portion 22 and the outer width W2 of the first parallel portion 35 are smaller than, for example, the diameter φ of the through hole 13. Therefore, the tip portion 22 and the first parallel portion 35 of the press-fit terminal 20 are inserted into the through-hole 13 with a gap at least one of the side portions with respect to the through-hole 13.

The outer width W4 of the second parallel portion 37 is larger than that of the through hole 13. Further, the inclined portion 36 gradually widens from the first parallel portion 35 toward the second parallel portion 37. Therefore, the outer width of the two contact pieces 34 increases toward the second parallel portion 37, and exceeds the diameter φ of the through hole 13 at the inclined portion 36. Therefore, when the press-fit terminal 20 is further inserted, as shown in FIG. 2, at the position of the inclined portion 36 away from the tip of the eye hole 31, the two contact pieces 34 are on the inner peripheral surface of the through hole 13 (particularly). It comes into contact with the part near the opening edge). When the press-fit terminal 20 is pushed in from this state, the force with which the outer edge of the inclined portion 36 of the two contact pieces 34 is pressed against the inner peripheral surface of the through hole 13 pushes the two contact pieces 34 inward. It acts as a deforming force. Therefore, the two contact pieces 34 are deformed in the direction of approaching each other so as to narrow the distance between the eye holes 31.

At this time, the two contact pieces 34 are pushed inward at the position of the inclined portion 36 away from the tip end side of the eye hole 31. Therefore, the two contact pieces 34 are easily deformed not only at the connecting portion to the tip portion 22 but also at the intermediate portion in the length direction. That is, when the press-fit portion 30 is inserted into the through hole 13, the two contact pieces 34 are deformed so that the second parallel portion 37 is displaced inward. At this time, the two contact pieces 34 are deformed at a portion closer to the tip portion 22 and a portion closer to the base end portion 26 with respect to the second parallel portion 37. Regarding the deformation of the portion of the two contact pieces 34 closer to the tip portion 22, the deformed portion is inclined from the portion where the two contact pieces 34 are connected to the tip portion 22 (here, the tip end side inclined portion 38). It will be dispersed in the part 36. In particular, since the inclined portion 36 of the two contact pieces 34 is pushed inward, the inclined portion 36 and the first parallel portion 35 are easily deformed at the connecting portion.

Then, as shown in FIG. 3, the second parallel portion 37 is press-fitted into the through hole 13, and the portion of the second parallel portion 37 closer to the base end portion 26 is located in the through hole 13. A state in which the press-fit terminal 20 is press-fitted into the through hole 13 with the second parallel portion 37, particularly the portion of the second parallel portion 37 closer to the base end portion 26 pressed against the inner peripheral surface of the through hole 13. It becomes.

As a result, the substrate 10 with the press-fit terminal in which the press-fit terminal 20 is press-fitted into the through hole 13 is manufactured.

According to the press-fit terminal 20 or the substrate with the press-fit terminal 10 configured in this way, the deformed portions in the portion of the two contact pieces 34 near the tip portion 22 are dispersed in a plurality of locations. As a result, the maximum value of strain at each of the deformed portions dispersed in the two contact pieces 34 becomes small.

Hereinafter, preferred configuration examples will be described on the premise of the above embodiment.

It is assumed that the total length of the eye hole 31 is L, and the length from the tip of the eye hole 31 to the portion of the first parallel portion 35 that maintains the same inner width (the portion up to the inclined portion 36) is L1. In this case, the length L may be grasped as an element that determines the length of the contact piece 34 that can be deformed in the press-fit portion 30. Further, the length L1 may be grasped as an element that determines the distance of the deformed portions to be dispersed in the region of the contact piece 34 closer to the tip portion 22 than the second parallel portion 37.

For example, the lower limit of L1 is preferably 30% or more, more preferably 35% or more with respect to L. The upper limit of L1 is preferably 50% or less, more preferably 45% or less with respect to L.

When the ratio of the length L1 to the length L is not more than the above lower limit value, the deformed portion can be preferably dispersed. When the ratio of the length L1 to the length L is equal to or less than the above upper limit value, the distance between the deformed portions can be reduced. As a result, an appropriate contact load can be applied to the deformed portion. Therefore, by adjusting the range of L1 to the above range, it is easy to keep the maximum value of strain small while increasing the contact load.

The width W3 of the first parallel portion 35 of the two contact pieces 34 may be smaller than the width W5 of the second parallel portion 37 of the two contact pieces 34. The width W3 of the first parallel portion 35 of the two contact pieces 34 means the width W3 of the rectangular portion forming the first parallel portion 35 of each of the two contact pieces 34. Similarly, the width W5 of the second parallel portion 37 of the two contact pieces 34 means the width W5 of the rectangular portion forming the second parallel portion 37 of each of the two contact pieces 34.

When the press-fit terminal 20 is press-fitted into the through hole 13, the inclined portion 36 and the second parallel portion 37 of the two contact pieces 34 receive a force to deform inward. At this time, it is preferable that the two contact pieces 34 are deformed not only in the second parallel portion 37 but also in the first parallel portion 35. For that purpose, it is preferable that the two contact pieces 34 have a shape that can be easily deformed by the first parallel portion 35 rather than the second parallel portion 37. Therefore, if the width W3 of the first parallel portion 35 of the two contact pieces 34 is smaller than the width W5 of the second parallel portion 37 of the two contact pieces 34, the first parallel portion 35 of the two contact pieces 34 The part in is easily deformed. As a result, the two contact pieces 34 include the first parallel portion 35 and are easily deformed as a whole. As a result, the deformed portions of the two contact pieces 34 are more reliably dispersed.

Further, the thickness of the press-fit terminal 20 may be 0.3 mm or more and 0.5 mm or less.

That is, the thickness of the conventional press-fit terminal was about 0.6 mm. The press-fit terminal is used for a control unit such as an airbag, for example. In recent years, as the number of signals increases, the number of poles of terminals tends to increase. From the standpoint of the control unit, the connector does not exhibit any particular function, so there is a desire to make it smaller. Therefore, it is required to make the press-fit terminal smaller so that the connector does not become larger even if the number of poles increases. Against this background, the recent market demands press-fit terminals having a thickness of 0.5 or less, for example, a thickness of 0.4 mm.

Generally, when the thickness of the press-fit terminal is as thin as 0.5 mm or less, the through hole becomes smaller according to this size. Then, the width of the press-fit terminal has to be reduced. In such a case, as disclosed in Patent Document 1, it becomes difficult to secure a sufficient space for the press-fit terminal to provide the stress distribution portion. It is also difficult to provide a fine mountain-shaped stress distribution portion. In such a case, by adopting the configuration according to the present embodiment, it is possible to reduce the maximum value of strain while increasing the contact load.

Further, it is preferable that the press-fit terminal 20 is press-fitted into the through hole 13, that is, the substrate 10 with the press-fit terminal has the following configuration.

For example, it is preferable that the outer width W2 of the first parallel portion 35 is smaller than the diameter φ of the through hole 13, and the second parallel portion 37 is in contact with the inner peripheral surface of the through hole 13. As described above, if the outer width W2 of the first parallel portion 35 is smaller than the diameter φ of the through hole 13, the first parallel portion 35 is not in a state of being press-fitted into the through hole 13. Therefore, both side portions or one side portion of the first parallel portion 35 are in a state of not contacting the inner peripheral surface of the through hole 13. If the outer width W4 of the second parallel portion 37 is larger than the diameter φ of the through hole 13, the second parallel portion 37 is press-fitted into the through hole 13. That is, both side portions of the second parallel portion 37 are in contact with each other in a pressed state against the inner peripheral surface of the through hole 13.

In such a configuration, in a state where the press-fit terminal 20 is press-fitted into the through hole 13, the two contact pieces 34 are not narrowed in the first parallel portion 35, but are narrowed mainly in or near the second parallel portion 37. It is transformed like this. Therefore, as described above, it is understood that the contact load is large and the maximum value of strain is small.

Further, for example, it is preferable that the outer portions of the two contact pieces 34 are in contact with the inner peripheral surface of the through hole 13 in a state where the inner portions of the two contact pieces 34 are in contact with each other. This is expected to have the effect of suppressing an increase in the maximum value of distortion.

As shown in FIG. 4, the substrate 10 with a press-fit terminal may be incorporated in the device 50.

The device 50 includes a substrate 10 with a press-fit terminal and a case 52.

As described above, the substrate 10 with the press-fit terminal includes the substrate 12 and the press-fit terminal 20 press-fitted into the substrate 12. In FIG. 4, the connector terminal portion 54 is integrally connected to the base end portion 26 of the press-fit terminal 20. The connector terminal portions 54 are connected to the base end portion 26 in a bent state (here, a bent state at a right angle). The base end portion and the connector terminal portion 54 of the press-fit terminal 20 are incorporated in the connector housing 60. The connector terminal portion 54 is arranged so as to project from the bottom of the space in the connector housing 60 toward the opening. Here, a plurality of press-fit terminals 20 are incorporated in the connector housing 60. Therefore, a plurality of connector terminal portions 54 are lined up at intervals in the connector housing 60. Further, a plurality of press-fit terminals 20 project from the outer surface of the connector housing 60. Then, a plurality of press-fit terminals 20 projecting from the outer surface of the connector housing 60 are simultaneously press-fitted into the plurality of through holes 13. The connector housing 60 is mounted and fixed on the substrate 12 in a state where the plurality of press-fit terminals 20 are press-fitted into the plurality of through holes 13.

The case 52 is formed in a housing shape having a space capable of accommodating the substrate 12. The case 52 is formed with an opening 53 that exposes the connector housing 60 to the outside. The substrate 12 is fixed in the case 52 with the connector housing 60 disposed in the opening 53. For fixing the substrate 12 in the case 52, a screwed structure, a fitting structure, a composite structure thereof, or the like can be used.

In the device 50 as described above, a large number of connector terminal portions 54 may be incorporated in the connector housing 60. In this case, the work of press-fitting a large number of press-fit terminals 20 into the through holes 13 at the same time may occur. In such a case, it is effective in that the maximum value of distortion can be reduced while increasing the contact load for a large number of press-fit terminals 20.

FIG. 5 shows a press-fit terminal 220 according to a modified example. The press-fit terminal 220 differs from the press-fit terminal 20 in the following points.

That is, the two contact pieces 234 corresponding to the two contact pieces 34 include a third parallel portion 242 in addition to the first parallel portion 35, the second parallel portion 37, and the inclined portion 36. The third parallel portion 242 is a portion in which a part of the two contact pieces 234 is arranged in a parallel posture. More specifically, in the third parallel portion 242, a part of the two contact pieces 234 near the base end portion 26 is arranged in a parallel posture along the direction connecting the tip end portion 22 and the base end portion 26. Is. Therefore, the third parallel portion 242 is located closer to the base end portion 26 than the second parallel portion 37.

The outer width W13 of the third parallel portion 242 is smaller than the outer width W12 of the second parallel portion 37. Here, the second parallel portion 37 and the third parallel portion 242 are connected to each other via an additional inclined portion 241. The outer width W13 of the third parallel portion 242 is larger than the outer width W10 of the base end portion 26. The third parallel portion 242 is connected to the proximal end portion 26 via the proximal end side inclined portion 239. The outer width W13 of the third parallel portion 242 is larger than the outer width W1 of the tip portion 22. The inner width of the third parallel portion 242 may be the same as or smaller than the inner width of the second parallel portion 37. The width of each contact piece 234 in the third parallel portion 242 may be smaller than the width of each contact piece 234 in the second parallel portion 37.

More specifically, the third parallel portion 242 is located between the second parallel portion 37 and the proximal end portion 26. Here, of the two contact pieces 234, the intermediate portion in the direction in which they extend includes two square plate-shaped portions extending in a parallel posture in the direction connecting the tip end portion 22 and the base end portion 26. These two square plate-shaped portions are the third parallel portion 242. The outer edges of each of the two square plate-shaped portions are lined up in a parallel position. The inner edges of each of the two square plate parts are also lined up in a parallel position.

In the present embodiment, the two square plate-shaped portions in the third parallel portion 242 are connected to the second parallel portion 37 via the additional inclined portion 241. Here, of the two contact pieces 234, the portion between the second parallel portion 37 and the third parallel portion 242 is the additional inclined portion 241. The outer edges of the additional inclined portion 241 are formed so as to gradually narrow from the outer edges of the second parallel portion 37 toward the outer edges of the third parallel portion 242. The inner edge of the additional slope 241 is configured by the edge of the eye hole 31.

The width of the inner edge of the third parallel portion 242 (that is, the width of the eye hole 31 in the third parallel portion 242) is the width of the inner edge of the second parallel portion 37 (that is, the width of the eye hole 31 in the second parallel portion 37). It may be formed smaller than. In this case, both inner edges of the additional inclined portion 241 may be formed so as to gradually face inward in the width direction from the second parallel portion 37 toward the third parallel portion 242. The inner edge of the third parallel portion 242 may extend linearly along the direction connecting the proximal end portion 26 and the distal end portion 22.

In the present embodiment, the two square plate-shaped portions in the third parallel portion 242 are connected to the proximal end portion 26 via the proximal end side inclined portion 239. That is, of the two contact pieces 234, the portion between the third parallel portion 242 and the proximal end portion 26 is the proximal end side inclined portion 239. The outer edges of the base end side inclined portion 239 are formed so as to gradually narrow from the both outer edges of the third parallel portion 242 toward the outer edges of the base end portion 26. The width of each contact piece 234 in the base end side inclined portion 239 may be formed narrower than the other portion at the portion connected to the base end portion 26.

The outer width W13 of the third parallel portion 242 is preferably larger than the outer width W11 of the first parallel portion 35. The outer width W13 of the third parallel portion 242 is preferably larger than the diameter (diameter) φ of the through hole 13 into which the press-fit terminal 220 is inserted.

According to this modification, since the outer width of the third parallel portion 242 is smaller than the outer width of the second parallel portion 37, when the press-fit terminal 220 is inserted into the through hole 13, the two contact pieces 234 are placed on the second contact piece 234. Deformation is also likely to occur between the two parallel portions 37 and the third parallel portion 242. That is, when the press-fit terminal 220 is inserted into the through hole 13, the two contact pieces 234 are easily deformed not only on the distal end side but also on the proximal end side with respect to the second parallel portion 37. Therefore, the second parallel portion 37 is easily maintained in a posture parallel to the central axis of the through hole 13. As a result, the outer edge of the second parallel portion 37 tends to come into contact with the inner surface of the through hole 13 as a whole. As a result, the contact area between the two contact pieces 234 and the inner peripheral surface of the through hole 13, that is, the contact area becomes large. As a result, the connection state of the press-fit terminal 220 to the through hole 13 is stabilized, and the electrical connection reliability between the two is further improved.

Further, if the outer width W13 of the third parallel portion 242 is larger than the outer width W11 of the first parallel portion 35, the press-fit terminal 220 is likely to come into contact with the inner surface of the through hole 13 even in the third parallel portion 242. For example, by making the outer width W13 of the third parallel portion 242 larger than the diameter φ of the through hole 13, the two contact pieces 234 can be easily deformed on the third parallel portion 242 side, and the second parallel portion 37 And the third parallel portion 242 can be made to come into contact with the inner surface of the through hole 13. As a result, the contact area between the two contact pieces 234 and the inner surface of the through hole 13 becomes larger.

[Example]
In this embodiment, the evaluation of strain, load, and holding force of the press-fit terminal 20 described in the above embodiment will be described. The evaluation was derived by CAE (Computer Aided Engineering) analysis using the finite element method.

The press-fit terminal 20 was evaluated by changing the value of L1 / L. In Example 1, L1 / L is 0.33, and in Example 2, L1 / L is 0.38. In Example 3, L1 / L is 0.42, and in Example 4, L1 / L is 0.47. Further, in Example 2, L1 / L is 0.28, and in Example 3, L1 / L is 0.51. In any case, the thickness of the press-fit terminal 20 is 0.4 mm, and the diameter φ of the through hole 13 is 0.55 mm.

As an example 1 of comparison for evaluation, as shown in FIG. 6, a press-fit terminal 120 having a shape in which the first parallel portion 35 and the inclined portion 36 are omitted is prepared in the press-fit terminal 20. The press-fit terminal 120 was also evaluated for distortion, load, and holding force in the same manner as described above. The length L2 of the eye hole 131 is the same as the length L of the first embodiment.

The evaluation result is shown in FIG. The strain is represented by the displacement of the reference point near the boundary between the contact piece 34 and the tip portion 22. The load is the force exerted by the contact piece 34 on the inner peripheral surface of the through hole 13. The holding force is a force required for the press-fit terminal 20 to pull out from the through hole 13. In FIG. 7, the evaluation value (%) for each item of Example 1, Example 2, Example 3, Example 4, Example 2, and Example 3 is taken as 100% for each item of Example 1. ) Is shown.

As shown in the figure, it can be seen that the strains of Example 2, Example 1 to Example 4, and Example 3 are smaller than the strain of Example 1. Further, it can be seen that the load and holding force of Examples 2, Examples 1 to 4 and Example 3 are larger than the load and holding force of Example 1. As a result, it can be seen that in any of the cases of Example 2, Example 1 to Example 4, and Example 3, the contact load becomes large and the maximum value of strain becomes small.

In particular, from the balance between reducing the strain and increasing the holding force, it can be seen that Examples 1 to 4 are more effective. Therefore, it is presumed that it is more effective when L1 is 30% or more and 50% or less with respect to L.

Further, among Examples 1 to 4, Examples 2 and 3 are more advantageous from the viewpoint of the above balance. Therefore, it is presumed that it is more effective when the value of L1 / L is 35% or more and 45% or less.

It should be noted that the configurations described in the above-described embodiment and each modification can be appropriately combined as long as they do not conflict with each other.

10 Substrate with press-fit terminal 12 Substrate 13 Through-hole 13f Conductive layer 20, 120, 220 Press-fit terminal 22 Tip 22a Tip 26 Base end 30 Press-fit 31, 131 Eye hole 34 Contact piece 35 First parallel section 36 Inclined part 37 Second parallel part 38 Tip side inclined part 39 Base end side inclined part 50 Equipment 52 Case 53 Opening 54 Connector terminal part 60 Connector housing 234 Contact piece 239 Base end side inclined part 241 Additional inclined part 242 Third parallel part V1 Inner width of the first parallel part V2 Inner width of the second parallel part W1 Maximum width of the tip part W2 Outer width of the first parallel part W3 Width of the first parallel part of the contact piece W4 Outer width of the second parallel part W5 Width of the contact piece in the second parallel portion φ Diameter of through hole W10 Outer width of the base end portion W11 Outer width of the first parallel portion W12 Outer width of the second parallel portion W13 Outer width of the third parallel portion

Claims (10)

A press-fit terminal that is press-fitted into a through hole formed in a substrate.
It has a tip, a press-fit, and a base that are connected in order.
The width of the press-fit portion is larger than the maximum width of the tip portion.
The press-fit portion includes two contact pieces facing each other across the eye hole.
The two contact pieces include a first parallel portion arranged in a parallel posture, a second parallel portion arranged in a parallel posture, and an inclined portion.
The outer width of the first parallel portion is larger than the maximum width of the tip portion.
The outer width of the second parallel portion is larger than the outer width of the first parallel portion.
The first parallel portion is located closer to the tip portion than the second parallel portion.
The inclined portion connects the first parallel portion and the second parallel portion, and forms the inclined portion.
The inclined portion is a press-fit terminal that expands outward in the width direction from the first parallel portion toward the second parallel portion. The press-fit terminal according to claim 1.
A press-fit terminal having an inner width of the second parallel portion larger than the inner width of the first parallel portion. The press-fit terminal according to claim 1 or 2.
When the total length of the eye hole is L, and the length from the tip of the eye hole to the portion of the eye hole that maintains the same inner width in the first parallel portion is L1.
The L1 is a press-fit terminal which is 30% or more and 50% or less with respect to the L. The press-fit terminal according to any one of claims 1 to 3.
A press-fit terminal whose width at the first parallel portion of the two contact pieces is smaller than the width at the second parallel portion of the two contact pieces. The press-fit terminal according to any one of claims 1 to 4.
A press-fit terminal having a thickness of 0.3 mm or more and 0.5 mm or less. The press-fit terminal according to any one of claims 1 to 5.
The two contact pieces further include a third parallel portion arranged in a parallel position.
The third parallel portion is located closer to the base end portion than the second parallel portion.
A press-fit terminal whose outer width of the third parallel portion is smaller than the outer width of the second parallel portion. The press-fit terminal according to claim 6.
A press-fit terminal having an outer width of the third parallel portion larger than the outer width of the first parallel portion. Substrate with through holes and
The press-fit terminal according to any one of claims 1 to 7, wherein the press-fit portion is press-fitted into the through hole.
With
A substrate with a press-fit terminal, wherein the outer width of the first parallel portion is smaller than the diameter of the through hole, and the second parallel portion is in contact with the inner peripheral surface of the through hole. Substrate with through holes and
The press-fit terminal according to any one of claims 1 to 7, wherein the press-fit portion is press-fitted into the through hole.
With
A substrate with a press-fit terminal in which the outer portions of the two contact pieces are in contact with the inner peripheral surface of the through hole while the inner portions of the two contact pieces are in contact with each other. The substrate with the press-fit terminal according to claim 8 or 9.
A case for accommodating the press-fit terminal and
Equipment equipped with.

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