CN112470011A

CN112470011A - Contact pin and socket for electronic component

Info

Publication number: CN112470011A
Application number: CN201980049452.XA
Authority: CN
Inventors: 坂本泰之; 三浦玲
Original assignee: Enplas Corp
Current assignee: Enplas Corp
Priority date: 2018-07-27
Filing date: 2019-07-26
Publication date: 2021-03-09
Anticipated expiration: 2039-07-26
Also published as: JP7096095B2; TW202013836A; JP2020016620A; TWI808225B; WO2020022493A1; PH12020552280A1; CN112470011B

Abstract

The present invention is provided with: a conductive cylinder 32; a plunger 31 including a substrate side small diameter portion 31a and a terminal side large diameter portion 31b, the substrate side small diameter portion 31a being provided on one end portion side and coming into contact with an inner wall surface of the conductive cylinder to conduct electricity to the connection portion 9 of the wiring substrate P, the terminal side large diameter portion 31b being provided on the other end portion side and having a tip portion 31c coming into contact with a part of the terminal 4a of the electronic component 4; and a spring 33, one end portion 33a of which abuts against the root portion 31d of the terminal side large diameter portion, and the other end portion 33b of which abuts against the opening peripheral edge of the conductive cylinder and is compressed by being pressed, wherein in the pressed state, a position where the tip portion contacts with a part of the terminal and a position where the one end portion abuts against the root portion are located on a diagonal line of the terminal side large diameter portion where a rotational force is generated by a force of the terminal pressing the tip portion and a force of the spring pushing back the root portion. This makes it possible to prevent the electrical path from being electrically insulated without using a special structure.

Description

Contact pin and socket for electronic component

Technical Field

The present invention relates to a contact pin of a socket for an electronic component used for performance test of an electronic component such as an IC package, and more particularly, to a contact pin for realizing insulation of a conduction path for preventing formation of an electrical connection, and a socket for an electronic component including the contact pin.

Background

Conventionally, when an inspection object such as a semiconductor integrated circuit is inspected, a contact pin for electrically connecting the inspection object and an inspection substrate on a measuring instrument side is generally used (for example, see patent document 1). In addition, the contact pin is sometimes referred to as a "contact probe".

Patent document 1 discloses a contact pin including a first plunger for connecting to an inspection object, a second plunger for connecting to an inspection substrate, and a spring for applying a biasing force in a direction in which the first plunger and the second plunger are separated from each other, wherein a contact point portion between the first plunger and the second plunger is configured such that a columnar portion of one plunger is slidably fitted to an inner periphery of a cylindrical portion of the other plunger, and the columnar portion includes an elastic deformation portion which is brought into contact with an inner periphery of the cylindrical portion by a reaction force generated by elastic deformation.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-256251

Disclosure of Invention

Problems to be solved by the invention

However, if the contact pin as described above is used, the elastically deformable portion has a special shape, and therefore the contact area with the inner peripheral surface of the cylindrical portion may be limited.

In view of the above, an object of the present invention is to provide a contact pin that realizes insulation of a conduction path for preventing formation of electrical connection without using a special shape such as the above elastic deformation portion, and a socket for an electronic component including the contact pin.

Means for solving the problems

In order to solve the above problem, a contact pin (the invention of claim 1 of the present application) according to the present invention is a contact pin for electrically connecting an electronic component and a wiring board, the contact pin including: a conductive cylinder having an opening at one end and formed in a cylindrical shape; a plunger including a substrate-side small diameter portion and a terminal-side large diameter portion, the substrate-side small diameter portion being provided on one end portion side and being brought into contact with an inner wall surface of the conductive cylinder to be electrically connected to the connection portion of the wiring substrate by being inserted into the opening of the conductive cylinder, and the terminal-side large diameter portion being provided on the other end portion side and having a tip portion contacting a part of the terminal of the electronic component; and a spring, one end of which abuts against the root of the terminal-side large-diameter portion and the other end of which abuts against the opening peripheral edge of the conductive cylinder, and which contracts when the electronic component is pressed. In a state where the electronic component is pressed, a position where a tip portion of the terminal-side large diameter portion of the plunger contacts a part of the terminal of the electronic component and a position where one end portion of the spring abuts against a root portion of the terminal-side large diameter portion are located on a diagonal line of the terminal-side large diameter portion where a rotational force is generated by a force of the terminal pressing the tip portion and a force of the spring pushing back the root portion.

Further, a contact pin according to the present invention (invention of claim 2) for electrically connecting an electronic component to a wiring board, includes: a conductive cylinder having both ends opened and formed in a cylindrical shape; a terminal-side plunger which is in contact with a terminal of the electronic component and a substrate-side plunger which is in contact with and electrically connected to a connection portion of the wiring substrate, the terminal-side plunger and the substrate-side plunger being held at both end portions of the conductive cylinder, and a part of the terminal-side plunger and the substrate-side plunger being inserted into the conductive cylinder; and a spring that is pressed and contracted by the electronic component by applying a biasing force to the terminal-side plunger and the substrate-side plunger in a direction in which the terminal-side plunger and the substrate-side plunger are separated from each other in the conductive cylinder. The terminal-side plunger includes: a terminal side small diameter portion which is joined to an inner wall surface of the conductive cylinder in a state of being inserted into the conductive cylinder and abuts against one end of the spring at a root portion; and a terminal-side large-diameter portion provided in a state of protruding from the conductive tube, and having a tip portion that comes into contact with a part of the terminal of the electronic component. In a state where the electronic component is pressed, a position where a tip portion of the terminal-side large diameter portion of the terminal-side plunger comes into contact with a part of a terminal of the electronic component and a position where one end portion of the spring abuts against the root portion of the terminal-side small diameter portion of the terminal-side plunger are located on a diagonal line of the terminal-side plunger where a rotational force is generated by a force of the terminal pressing the tip portion and a force of the spring pushing back the root portion.

Further, the socket for electronic components of the present invention (invention of claim 7) includes: a frame body having a housing section for electronic components electrically connected to the wiring board; and a plurality of contact pins which are respectively inserted into a plurality of insertion holes of a support plate provided below the housing portion to electrically connect terminals of the electronic component and connection portions of the wiring board, wherein the socket for electronic components includes the contact pins described in the above-described means for solving the problem as the contact pins.

Effects of the invention

According to the contact pin of the present invention (invention according to claim 1 of the present invention), in a state where the electronic component is pressed, a position where a tip portion of the terminal-side large diameter portion of the plunger contacts a part of the terminal of the electronic component and a position where one end portion of the spring abuts against a root portion of the terminal-side large diameter portion are located on a diagonal line of the terminal-side large diameter portion where a rotational force is generated by a force of the terminal pressing the tip portion and a force of the spring pushing back the root portion. Thus, the contact pin can push the side portion of the substrate-side small-diameter portion toward the inner wall surface of the conductive barrel by a pressing force generated by a moment of force generated due to the rotational force. Therefore, it is possible to prevent the insulating of the current-carrying path for forming the electrical connection without using a special shape such as the elastic deformation portion of the conventional example and without applying a current to the spring.

Further, according to the contact pin of the present invention (the invention of claim 2 of the present application), in a state where the electronic component is pressed, a position where a tip portion of the terminal-side large diameter portion of the terminal-side plunger contacts a part of a terminal of the electronic component and a position where one end portion of the spring contacts a root portion of the terminal-side small diameter portion of the terminal-side plunger are located on a diagonal line of the terminal-side plunger where a rotational force is generated by a force of the terminal pressing the tip portion and a force of the spring pushing back the root portion. Thus, the contact pin can push the side portion of the substrate-side plunger toward the inner wall surface of the conductive cylinder by a pressing force generated by a moment of force generated due to the rotational force. Therefore, it is possible to prevent the insulating of the current-carrying path for forming the electrical connection without using a special shape such as the elastic deformation portion of the conventional example and without applying a current to the spring.

Further, according to the socket for electronic components of the present invention (the invention of claim 7 of the present application), by using the contact pin of the present invention, it is possible to prevent the contact pin from having a special shape such as the elastic deformation portion of the conventional example, and to prevent the contact pin from passing a current to the spring, thereby preventing the electrical path for electrical connection from being formed.

Drawings

Fig. 1 is a plan view showing an embodiment of a socket for electronic components of the present invention.

Fig. 2 is a front view of fig. 1.

Fig. 3 is a sectional view taken along line a-a of fig. 1.

Fig. 4 is an enlarged front view of the contact pin of the first embodiment.

Fig. 5 is a sectional view of the contact pin shown in fig. 4.

Fig. 6 is an explanatory diagram showing a relationship between forces generated by pressing the IC package.

Fig. 7 is an explanatory diagram of a comparative example showing the relationship of the forces in fig. 6.

Fig. 8A is an explanatory diagram relating to the phase shift between the springs.

Fig. 8B is an explanatory diagram relating to the phase shift between the springs.

Fig. 8C is an explanatory diagram relating to the phase shift between the springs.

Fig. 9A is an explanatory diagram relating to phase shift in the case where the shape of the spring shown in fig. 8A to 8C is partially different.

Fig. 9B is an explanatory diagram relating to phase shift in the case where the shape of the spring shown in fig. 8A to 8C is partially different.

Fig. 9C is an explanatory diagram relating to phase shift in the case where the shape of the spring shown in fig. 8A to 8C is partially different.

Fig. 10 is an explanatory diagram illustrating a structure of positioning the terminal-side large diameter portion of the plunger and the spring.

Fig. 11 is an explanatory diagram illustrating a structure of positioning the terminal-side large diameter portion of the plunger and the spring.

Fig. 12 is an explanatory diagram illustrating a structure of positioning the terminal-side large diameter portion of the plunger and the spring.

Fig. 13 is an explanatory diagram illustrating a structure of positioning the terminal-side large diameter portion of the plunger and the spring.

Fig. 14 is a front view of the contact pin of the second embodiment.

Fig. 15 is a cross-sectional view of the contact pin shown in fig. 14.

Fig. 16 is an explanatory diagram showing a relationship between forces generated by pressing the IC package.

Fig. 17 is an explanatory diagram of a comparative example showing the relationship of the forces in fig. 16.

Fig. 18A is an explanatory diagram showing an example of a use state of the contact pin of fig. 14.

Fig. 18B is an explanatory diagram showing an example of a use state of the contact pin of fig. 14.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a plan view showing an embodiment of a socket for electronic components of the present invention. Fig. 2 is a front view of fig. 1, and fig. 3 is a sectional view taken along line a-a of fig. 1. The socket 1 for electronic components is used for performance testing of electronic components such as IC packages, and includes a housing 2 and contact pins 3.

The housing 2 is a member for accommodating an electronic component to be tested, for example, an IC package 4, and is formed to be disposed on the wiring substrate P as shown in fig. 2 and 3. As shown in fig. 1 to 3, the frame body 2 is formed in a rectangular block shape from an insulating material, and a housing portion 5 of the IC package 4 is formed in a central portion of an upper surface thereof, for example. The housing portion 5 fixes and houses the IC package 4 electrically connected to the wiring board P shown in fig. 2, and positions the four corners of the IC package 4 with corner guides or the like.

As shown in fig. 3, the housing 2 is provided with a support plate 6 and a bottom plate 7 below the housing 5. The support plate 6 is formed of a plate material formed into a flat plate shape with an insulating material, and the bottom plate 7 is similarly formed of a plate material formed into a flat plate shape with an insulating material, and is fixed to the lower surface side of the support plate 6, while accommodating the IC package 4 on the upper surface side.

As shown in fig. 3, a plurality of insertion holes having a circular cross section penetrating in the vertical direction are formed in the support plate 6 and the bottom plate 7 located below the housing portion 5, and the contact pins 3 are inserted into the insertion holes in the vertical direction. Thereby, as shown in fig. 1, a large number of contact pins 3 are inserted over the entire area of the accommodation portion 5 having an expansion, for example, rectangular plane. These contact pins 3 serve as connecting portions for electrically connecting terminals of the IC package 4 and the wiring board P, and are formed in a so-called surface pressure bonding type.

Although not shown in fig. 1 to 3, in fig. 2, a socket cover is provided to be openable and closable with one end (for example, the right end) as a rotation center, and covers the IC package 4 and fixes the IC package 4 in a state where the IC package 4 is accommodated in the accommodating portion 5.

Next, the contact pin of the first embodiment will be described. Fig. 4 is a front view of the contact pin of the first embodiment. Specifically, fig. 4 is an enlarged front view showing the contact pin 3 used in the socket 1 for electronic components shown in fig. 1. Fig. 5 is a sectional view showing the contact pin of fig. 4. In the first embodiment, first, an application example using an outer spring type contact pin in which a spring member can be visually confirmed will be described.

The contact pins 3 electrically connect the IC package 4 and the wiring board P. Specifically, the contact pins 3 electrically connect the terminals 4a of the IC package 4 and the connection pads (connection portions) 9 of the wiring substrate P (see fig. 6). The contact pin 3 includes a plunger 31, a conductive cylinder 32, and a spring 33. In fig. 18A and 18B showing a usage state described later, the terminal 4a is, for example, a solder ball 8.

In detail, as shown in fig. 5, the plunger 31 includes: a substrate-side small-diameter portion 31a provided on one end portion side, inserted into the opening of the conductive cylinder 32 and brought into contact with the inner wall surface of the conductive cylinder 32, thereby being electrically connected to the connection portion 9 (see fig. 6) of the wiring substrate P; and a terminal-side large diameter portion 31b provided on the other end portion side and having a tip end portion 31c, the tip end portion 31c being in contact with a part of the terminal 4a (see fig. 6) of the IC package 4. The plunger 31 is made of a conductive material such as metal. The terminal-side large diameter portion 31b has: a front end portion 31c partially contacting the terminal 4a of the IC package 4; and a root portion 31d abutting against one end portion 33a of the spring 33. The substrate-side small diameter portion 31a and the terminal-side large diameter portion 31b are connected by a shaft portion 31 e.

A part of the plunger 31 (a region including the substrate-side small diameter portion 31 a) is inserted into the conductive cylinder 32. The conductive cylinder 32 is provided with a tapered opening peripheral edge portion 32a which abuts against the other end portion 33b of the spring 33.

As shown in fig. 5, one end 33a of the spring 33 abuts on the root portion 31d of the terminal-side large-diameter portion 31b, and the other end 33b abuts on the opening peripheral portion 32a of the conductive tube 32, and the spring 33 is contracted by the above-described pressing force. Specifically, the spring 33 is, for example, a coil spring, and is wound around the plunger 31 to apply a biasing force in a direction to separate the opening peripheral edge portion 32a and the root portion 31d of the conductive barrel 32 and the terminal-side large-diameter portion 31b from each other. Here, the periphery of the plunger 31 is a region where the spring 33 is wound around the plunger 31 from one end 33a of the spring 33 to the other end 33b of the spring 33.

Next, the operation of the contact pin 3 of the first embodiment will be described. Fig. 6 is an explanatory diagram showing a relationship between forces generated by pressing the IC package.

In fig. 6, in a state where the IC package 4 is pressed, a position where the tip portion 31c of the terminal-side large-diameter portion 31b of the plunger 31 contacts a part of the terminal 4a of the IC package 4 and a position where one end portion 33a of the spring 33 contacts the root portion 31d of the terminal-side large-diameter portion 31b are located on diagonal lines of the terminal-side large-diameter portion 31b where a rotational force is generated by a force of the terminal 4a pressing the tip portion 31c and a force of the spring 33 pushing back the root portion 31 d.

Here, the position where the tip portion 31c contacts a part of the terminal 4a of the IC package 4 functions as a point of action of force by which the terminal 4a of the IC package 4 presses the tip portion 31c in a pressed state. The position where the one end portion 33a of the spring 33 abuts against the root portion 31d of the terminal-side large-diameter portion 31b functions as a reaction point of a force with which the one end portion 33a of the spring 33 is pushed back to the root portion 31d in the pressed state. In the following description of the contact pin 3 according to the first embodiment, a position at which the distal end portion 31c contacts a part of the terminal 4a may be referred to as an "operating point". The position where one end 33a of the spring 33 abuts the root 31d may be referred to as a "reaction point". Further, a straight line connecting the operating point and the reaction point forms a diagonal line.

Specifically, in fig. 6, by pressing from the IC package 4, if the terminal 4a is pressed with a force F₁When the tip end portion 31c is pressed, a reaction force (-F) is generated in which one end portion 33a of the spring 33 pushes back the root portion 31d of the terminal-side large-diameter portion 31b as a reaction force thereof₁) (negative signs mean opposite orientations). In this case, it becomes F₁Line of action A₁With reaction force (-F)₁) Line of action A₂Parallel, generating a force F₁With reaction force (-F)₁) Two forces of equal magnitude and opposite direction are generated, thus generating moments of two forces (couple). When the clockwise rotation is positive, the moment M of the two forces₁Represented by the following formula.

M₁＝F₁×L₁…(1)

Here, L₁Is the distance between the lines of action of the moments of the two forces. In particular, the joining force F₁Point of action and reaction force (-F)₁) Sin θ component of the distance (diagonal) of the reaction point of (a).

Due to the force F₁+ reaction force (-F)₁) When the force is equal to 0, the two moments of force do not generate a force for moving the plunger 31 in the X direction or the Y direction, but generate a rotational force (moment of couple).

In the present embodiment, since the tip portion 31c of the terminal-side large diameter portion 31b of the plunger 31 has a tapered shape that contacts a part of the terminal 4a, a clockwise rotational force is applied to the plunger 31 with the tip portion 31c as a fulcrum in fig. 6.

On the other hand, since the substrate-side small diameter portion 31a is inserted into the conductive cylinder 32, the plunger 31 does not rotate with respect to the clockwise rotation force, and a static balance is established. In this case, the fulcrum of the distal end 31c is separated by a distance L₂The moment M of the force acting on the substrate-side small diameter portion 31a at the position (D)₂Represented by the following formula.

M₂＝F₂×L₂…(2)

In this case, since the static balance is established, the formula (1) may be changed to the formula (2), and the following formula is established.

F₁×L₁＝F₂×L₂…(3)

According to the formula (3), the pressing force F₂Represented by the following formula.

F₂＝((F₁×L₁)/L₂)…(4)

According to formula (4), distance L₁The larger the value of (A), the larger the pressing force F acting on the substrate-side small diameter portion 31a₂The larger becomes. This means that the greater the value of the distance of the diagonal line connecting the tip portion 31c and the root portion 31d, the greater the distance L₁The larger the value of (a) becomes. Thereby, the contact pin 3 can utilize the pressing force F₂The side of the substrate-side small-diameter portion 31a is pushed toward the inner wall surface of the conductive cylinder.

Fig. 7 is an explanatory diagram of a comparative example showing the relationship of the forces in fig. 6. In comparison with the contact pin 3 shown in fig. 6, the contact pin 30 shown in fig. 7 has one end 33a of the spring 33 provided on the opposite side in the circumferential direction, and has the other end 33b provided on the opposite side in the circumferential direction. In addition, although the structure of the opening peripheral edge of the conductive tube 32 is slightly different from that of the contact pin 3 in the comparative example for convenience of explanation, the structure of the opening peripheral edge of the conductive tube 32 has no influence on the generation of the rotational force (moment of couple).

In the comparative example shown in fig. 7, in a state where the IC package 4 is pressed, the position where the tip portion 31c of the terminal-side large diameter portion 31b of the plunger 31 contacts a part of the terminal 4a is the same as the contact pin 3, but the position where one end portion 33a of the spring 33 contacts the terminal-side large diameter portion 31b is located at the root portion on the opposite side of the root portion 31 d. In this case, F becomes₁Line of action A₁With reaction force (-F)₁) Line of action A₂Parallel, generating a force F₁With reaction force (-F)₁) Two forces of equal magnitude and opposite direction are generated, thus generating moments of two forces (couple). But it was found that: represents the line of action A₁And line of action A₂Distance L between spaced lines of action₃Than the distance L shown in FIG. 6₁Short, and therefore the pressing force F acting on the substrate-side small-diameter portion 31a₂And becomes smaller as compared with the case of fig. 6.

Therefore, the posts are pressed in the state where the IC package 4 is pressedThe position where the tip end 31c of the terminal-side large-diameter portion 31b of the plug 31 contacts a part of the terminal 4a and the position where one end 33a of the spring 33 contacts the root of the terminal-side large-diameter portion 31b are preferably located on the diagonal line of the terminal-side large-diameter portion 31b so that the distance L is set₁The value of (c) becomes large. This means that the distance L₁The larger the value of (3), the larger the rotational force caused by the force of the terminal 4a pushing the tip portion 31c and the force of the spring 33 pushing back to the root portion. That is, the root is preferably the position of the root 31d shown in fig. 6.

In the present embodiment, for example, it is preferable that the spring 33 is pushed into a predetermined design position by pressing from the IC package 4, and thereby in the contracted state, one end 33a of the spring 33 and the other end 33b of the spring 33 are arranged as shown in fig. 6 and are shifted in phase by 180 degrees. When the phases are shifted by 180 degrees by the arrangement shown in fig. 6, the distance L between the moments of the two forces (the moment of the couple of forces)₁Becomes maximum (see fig. 6). In the present embodiment, the distance L₁The maximum value of (A) means that the action line A shown in FIG. 6 is shown in design₁And line of action A₂Distance L between spaced lines of action₁Becomes the maximum value, and the distance L in this case is defined as follows₁Referred to as the "maximum distance".

Fig. 8A to 8C are explanatory views of the spring with respect to the phase shift. Fig. 8A is a front view of the contact pin 3 shown in fig. 4 with the spring 33 removed. FIG. 8B is a graph taken from Y₁A top view looking in the direction of the spring 33. FIG. 8C is a graph taken from Y₂Spring 33 is seen in a top view from the direction. In the present embodiment, the phase shift of 180 degrees means when it is shifted from Y₁Direction or Y₂The positional relationship between one end 33a of the spring 33 shown in fig. 8B and the other end 33B shown in fig. 8C is shifted by 180 degrees when viewed in the direction.

In the present embodiment, as shown in fig. 6, by providing the opening peripheral edge portion 32a having a tapered shape which abuts against the other end portion 33b of the spring 33, the other end portion 33b is configured to be caught by the opening peripheral edge portion 32a having a tapered shape. Therefore, the IC package 4 is pressedThe other end 33b transmits a load of a force pressing the opening peripheral edge 32a to the conductive cylinder 32 without acting on the plunger 31, and thus applies a pressing force F₂There is no effect.

As described above, according to the contact pin 3 of the first embodiment, the position where the tip portion 31c contacts a part of the terminal 4a and the position where the one end portion 33a of the spring 33 contacts the root portion 31d can be fixed. This can stably and strongly ensure a moment (moment of couple) of two forces generated by the action point and the reaction point. That is, the contact pin 3 of the first embodiment is a distance L due to a moment that will generate two forces₁The distance is fixed to the maximum distance, and unevenness in the force couple can be suppressed.

The distance L is set to be equal to the distance L of the contact pin 3 of the first embodiment₁A pressing force F generated by the moment of the force generated by the rotating force when the maximum distance is reached₂The side portion of the substrate-side small diameter portion 31a can be pushed toward the inner wall surface of the conductive tube 32. That is, the contact load of the side portion of the substrate-side small diameter portion 31a is stabilized and increased. Accordingly, the contact pin 3 according to the first embodiment can prevent the formation of insulation of the conducting path for electrical connection without adopting a special shape such as the above-described elastic deformation portion.

Next, a modified example of the first embodiment will be described. In a modification of the first embodiment, the plunger 31 is replaced with plungers 31A to 31D described below. Further, a spring 38 shown in fig. 9A to 9C is applied to the

plungers

31A, 31B, 31D.

Fig. 9A to 9C are explanatory views relating to phase shifts in the case where the shapes of the springs shown in fig. 8A to 8C are partially different. Fig. 9A is a front view of a spring 38 that can be applied to the contact pin 3 shown in fig. 4. FIG. 9B is a graph taken from Y₁A top view looking in the direction of the spring 38. FIG. 9C is a graph taken from Y₂A top view looking in the direction of the spring 38. The spring 33 differs from the spring 38 in that one end 38a of the spring 38 shown in fig. 9B has a projection facing the Y direction. In contrast, the other end 38b of the spring 38 shown in fig. 9C is the same as that shown in fig. 8A to 8CThe other end 33b of the spring 33 is the same.

Next, the shape of the terminal-side large-diameter portion 31b of the plungers 31A to 31D and the operational effects derived from the shape will be described.

Fig. 10 to 13 are explanatory views showing a structure of positioning the terminal-side large diameter portion of the plunger and the spring. The plungers 31A to 31D shown in fig. 10 to 13 are mainly explained about differences from the plunger 31 shown in fig. 5. Although the plungers 31A to 31D are illustrated as being cut off midway in the shaft portion 31e, the subsequent configuration is the same as that of the plunger 31.

First, the plunger 31A will be explained. Similar to the plunger 31 shown in fig. 5, the plunger 31A shown in fig. 10 has a terminal-side large diameter portion 31b, a tip portion 31c, and a root portion 31 d. However, the plunger 31A is different from the plunger 31 in that the root portion 31d has the hole portion 31 f. Specifically, a hole 31f is provided in a contact surface of the root portion 31d with which the one end portion 38a of the spring 38 is in contact, at a position (reaction point) where the one end portion 33a of the spring 38 is in contact with the diagonal root portion 31d, and a protruding portion of the one end portion 38a of the spring 38 is fixed to the hole 31f in advance. The other end 38b of the spring 38 is positioned at a position shifted by 180 degrees. The positional relationship between the tip portion 31c and the hole 31f is set so that the distance L is set as described above₁Becomes the maximum distance. Therefore, even when the plunger 31A is used, the contact pin 3 can utilize the pressing force F described above₂The side portion of the substrate-side small-diameter portion 31a is pushed toward the inner wall surface of the conductive tube 32, thereby preventing the conduction path for electrical connection from being insulated.

Next, the plunger 31B will be explained. Similarly to the plunger 31 shown in fig. 5, the plunger 31B shown in fig. 11 has a terminal-side large diameter portion 31B, a tip portion 31c, and a root portion 31 g. However, the plunger 31B is different from the plunger 31 in that it has a hole 31f in the root portion 31g and an inclined surface. The hole 31f is provided at a position to be a reaction point. Specifically, the root portion 31g abutting against the one end portion 38a of the spring 38 has an inclined surface, and as the IC package 4 is pressed, the one end portion 38a of the spring 38 slides on the inclined surface, and the one end portion 38a is inserted into the hole portion 31f and positioned at a position where the one end portion 38a of the spring 38 abuts against the diagonal root portion 31 g. Thereby, the other end 38b of the spring 38 is positioned at a position shifted by 180 degrees in phase.

In other words, when the spring 38 is assembled around the plunger 31B in a state where both end portions are not fixed and are free to rotate, when the spring 38 is pushed into a predetermined design position, the protruding portion of one end portion 38a of the spring 38 is inserted into the hole portion 31f by itself, and the other end portion 38B of the spring 38 is positioned at a position shifted by 180 degrees in phase. Therefore, even when the plunger 31B is used, the contact pin 3 can utilize the pressing force F described above₂The side portion of the substrate-side small-diameter portion 31a is pushed toward the inner wall surface of the conductive tube 32, thereby preventing the conduction path for electrical connection from being insulated.

Next, the plunger 31C will be explained. The plunger 31C shown in fig. 12 has a terminal-side large diameter portion 31b, a tip portion 31C, and a root portion 31h, similarly to the plunger 31 shown in fig. 5. However, the plunger 31C has an inclined surface (curved tapered surface) having a steeper inclination than the root portion 31g shown in fig. 11, and does not have a hole such as the hole 31f shown in fig. 11. In this case, by using the spring 33 shown in fig. 8A to 8C, when the spring 33 is pushed into a predetermined design position, one end portion 33a of the spring 33 is positioned at the distance L by self-induction₁Becomes the position of the maximum distance.

In other words, the root portion 31h abutting on the one end portion 33a of the spring 33 has an inclined surface (curved tapered surface), and as the IC package 4 is pressed, the one end portion 33a of the spring 33 slides on the inclined surface, and is positioned at a position (reaction point) where the one end portion 33a of the spring 33 abuts on the root portion 31h on the diagonal line. The other end 33b of the spring 33 is positioned at a position shifted by 180 degrees in phase.

Therefore, even when the plunger 31C is used, the contact pin 3 can utilize the pressing force F described above₂The side portion of the substrate-side small-diameter portion 31a is pushed toward the inner wall surface of the conductive tube 32, thereby preventing the conduction path for electrical connection from being insulated.

Next, the plunger 31D will be explained. Similarly to the plunger 31 shown in fig. 5, the plunger 31D shown in fig. 13 has a terminal-side large diameter portion 31b, a tip portion 31c, and a root portion 31 i. However, the plunger 31D is different from the plunger 31 in that it has a hole 31f in the root portion 31i and has a steep inclined surface (curved tapered surface) similar to the plunger 31C. In this case, as the spring 38 is pushed into the predetermined design position by the pressing force from the IC package 4, the one end 38a of the spring 38 moves along the inclined surface, and when pushed into the design position, the protruding portion of the one end 38a of the spring 38 is inserted into the hole 31 f. Thereby, the other end 38b of the spring 38 is positioned at a position shifted by 180 degrees in phase.

Therefore, even when the plunger 31D is used, the contact pin 3 can utilize the pressing force F described above₂The side portion of the substrate-side small-diameter portion 31a is pushed toward the inner wall surface of the conductive tube 32, thereby preventing the conduction path for electrical connection from being insulated. In the present embodiment, the spring 33 applied to the contact pin 3 may be freely rotatable, only one end 33a of the spring 33 may be fixed in advance, and the one end 33a and the other end 33b of the spring 33 may be fixed in advance. However, the arrangement shown in fig. 6 is made such that the phase is shifted by 180 degrees so as to make the distance L described above₁Becomes the maximum distance.

Next, the contact pin of the second embodiment will be described in detail. Hereinafter, the differences from the first embodiment will be mainly described. In the second embodiment, the contact pin of the inner spring type is adopted which is configured such that the spring cannot be visually confirmed from the outside, as compared with the contact pin of the outer spring type described in the first embodiment.

Fig. 14 is a front view of the contact pin of the second embodiment. Fig. 14 shows a contact pin for a socket for electronic components according to the present invention. Fig. 15 is a cross-sectional view of the contact pin shown in fig. 14.

The contact pin 3A electrically connects the IC package 4 shown in fig. 2 and the wiring substrate P, as in the contact pin 3 of the first embodiment. As shown in fig. 14, the contact pin 3A includes a conductive cylinder 34, a terminal-side plunger 35 that contacts a terminal of the IC package 4, and a substrate-side plunger 36 that contacts and conducts with a connection portion of the wiring substrate P shown in fig. 2, wherein the terminal-side plunger 35 and the substrate-side plunger 36 are held at both end portions of the conductive cylinder 34 and a part thereof is inserted into the conductive cylinder 34. As shown in fig. 15, the contact pin 3A includes a spring 37 therein.

The conductive tube 34 is made of a conductive material such as metal, and is formed in a tubular shape with both ends open as shown in fig. 15. A part of the terminal-side plunger 35 is inserted into the upper end of the conductive cylinder 34. The terminal-side plunger 35 is in contact with and electrically connected to the terminal 4a (see fig. 16) of the IC package 4, is made of a conductive material such as a metal, is formed into a circular rod shape of which a part can be fitted into the conductive cylinder 34, and is partially processed.

Specifically, the terminal-side plunger 35 includes: a terminal side small diameter portion 35a which is joined to an inner wall surface of the conductive tube 34 in a state of being inserted into the conductive tube 34 and abuts against one end portion 37a of the spring 37 at a root portion 35 d; and a terminal side large diameter portion 35b provided in a state of protruding from the conductive cylinder, and having a tapered tip portion 35c in contact with a part of the terminal of the IC package 4.

The protrusion of the inner wall surface of the conductive tube 34 is fitted into the intermediate tapered portion 35f in the circumferential direction to hold and fix the terminal side small diameter portion 35 a.

The substrate-side plunger 36 is inserted into the lower end of the conductive cylinder 34 so as to leave a part thereof. The substrate-side plungers 36 are in contact with and electrically connected to the connection pads 9 of the wiring substrate P shown in fig. 16, and are made of a conductive material such as metal.

The substrate-side plunger 36 has: a substrate side large diameter portion 36a, a side surface of the substrate side large diameter portion 36a being in contact with the inside of the conductive cylinder 34, and the substrate side large diameter portion 36a having a tapered protruding portion 36c in contact with the other end 37b of the spring 37; and an elongated base-side small diameter portion 36b, the base-side small diameter portion 36b having a smaller diameter than the base-side large diameter portion 36a, and the tip of the base-side small diameter portion 36b being in contact with the connection pad 9 of the wiring substrate P in a state in which a part thereof protrudes from the conductive cylinder 34. The substrate-side plunger 36 is formed in a circular rod shape in which the substrate-side large diameter portion 36a is fitted into the conductive cylinder 34 and is slidable by being pressed by the IC package 4.

A spring 37 is inserted between the terminal-side plunger 35 and the substrate-side plunger 36 inside the conductive cylinder 34. The spring 37 biases the terminal-side plunger 35 and the substrate-side plunger 36 in the conductive cylinder 34 in a direction in which the terminal-side plunger 35 and the substrate-side plunger 36 are separated from each other, and is pressed and contracted by the IC package 4. The spring 37 is made of a conductive material such as metal, and is a coil spring having an outer diameter smaller than the inner diameter of the conductive tube 34 so as to be expandable and contractible in the conductive tube 34.

Next, the operation of the contact pin 3A will be described.

Fig. 16 is an explanatory diagram showing a relationship between forces generated by pressing the IC package. In fig. 16, in a state where the IC package 4 shown in fig. 2 is pressed, a position where the tip portion 35c of the terminal-side large diameter portion 35b of the terminal-side plunger 35 contacts a part of the terminal 4a of the IC package 4 and a position where one end portion 37a of the spring 37 contacts the root portion 35d of the terminal-side small diameter portion 35a of the terminal-side plunger 35 are located on a diagonal line of the terminal-side plunger 35 where a rotational force is generated by a force with which the terminal 4a pushes the tip portion 35c and a force with which the spring 37 pushes back the root portion 35d of the terminal-side small diameter portion 35 a.

Here, the position where the tip portion 35c contacts a part of the terminal 4a in the pressed state functions as a point of action of the force pressing the tip portion 35c by the terminal 4a of the IC package 4. The position where one end 37a of the spring 37 abuts against the root 35d functions as a reaction point of the force of the spring 37 pushing back the root 35d of the terminal-side small diameter portion 35 a. In the following description of the contact pin 3A according to the second embodiment, a position at which the distal end portion 35c contacts a part of the terminal 4a may be referred to as an "operating point". The position where one end 37a of the spring 37 abuts against the root 35d may be referred to as a "reaction point".

Specifically, in fig. 16, by pressing from the IC package 4, if the terminal 4a is pressed with a force F₁When the tip end 35c is pressed, one end 37a of the spring 37 is generated as a reaction thereof to push the terminal sideReaction force (-F) of pushing back of root 35d of small diameter portion 35a₁). In this case, F₁Line of action A₁With reaction force (-F)₁) Line of action A₂Parallel, generating a force F₁With reaction force (-F)₁) Two forces of equal magnitude and opposite direction are generated, thus generating moments of two forces (couple). Moment M of the two forces₁Represented by the above formula (1).

The force F is the same as the contact pin 3 of the first embodiment₁+ reaction force (-F)₁) When the torque of the two forces is 0, the force for moving the terminal-side plunger 35 in the X direction and the Y direction is not generated, but the rotational force acts.

That is, in the present embodiment, since the tip portion 35c of the terminal side large diameter portion 35b of the terminal side plunger 35 has a tapered shape that partially contacts the terminal 4a of the IC package 4, the terminal side plunger 35 is rotated clockwise with the terminal side tip portion 35c as a fulcrum in fig. 16.

On the other hand, the terminal-side plunger 35 is incorporated in the conductive barrel 34 and does not rotate, and static balance is established. In this case, the fulcrum of the distal end portion 35c is separated by a distance L₂The moment M of the force acting on the substrate-side large diameter portion 36a at the position of (A)₂Represented by the above formula (2). Further, if the above-described expressions (3) to (4) are applied, the pressing force F with which the conductive cylinder 34 presses the substrate-side plunger 36 is obtained₂(see FIG. 16) is (F)₁×L₁)/L₂). With such a configuration, the conductive tube 34 applies a pressing force F to the contact pin 3A₂As a result, the side portion of the substrate side large diameter portion 36a can be pushed toward the inner wall surface of the conductive cylinder 34 by pressing the substrate side plunger 36. In addition, the pressing force F shown in fig. 16 is compared with that shown in fig. 6₂The position of the arrow in (b) is different from that in the case of fig. 6, a moment of force acts on the plunger 31, and in the case of fig. 16, a moment of force acts on the combined terminal-side plunger 35 and conductive barrel 34.

Fig. 17 is an explanatory diagram of a comparative example showing the relationship of the forces in fig. 16. In comparison with the contact pin 3A shown in fig. 16, the contact pin 30A shown in fig. 17 has one end 37a of the spring 37 provided on the opposite side in the circumferential direction, and has the other end 37b also provided on the opposite side in the circumferential direction.

The comparative example shown in fig. 17 has the following configuration: the positional relationship between the tip end portion 35c of the terminal-side large diameter portion 35b that is in contact with the terminal 4a of the IC package 4 and the one end portion 37a of the spring 37 is arranged so that the moment of the force generated by the force with which the tip end portion 35c is pressed by the terminal 4a by the pressing from the IC package 4 and the force with which the one end portion 37a of the spring 37 is pushed back to the terminal-side small diameter portion 35a becomes smaller as compared with fig. 16. That is, the action line A is shown₁And line of action A₂Distance L between spaced lines of action₃The moment of the couple is correspondingly smaller than in the case of fig. 16. Therefore, the configuration of the contact pin 3A is preferable to the contact pin 30A.

In the present embodiment, as in the case of the contact pin 3, when the spring 37 is pushed into a predetermined design position by the pressing force from the IC package 4, one end 37a of the spring 37 and the other end 37b of the spring 37 are shifted in phase by 180 degrees with respect to the contact pin 3A. This means that the action line A is shown with the distal end portion 35c as a fulcrum₁And line of action A₂Distance L between spaced lines of action₁Becomes maximum. In the present embodiment, by providing the tapered protruding portion 36c that abuts against the other end portion 37b of the spring 37, the other end portion 37b is configured to be caught by the tapered protruding portion 36c as shown in fig. 16. Therefore, in a state where the IC package 4 is pressed, the other end 37b transmits a load of a force pressing the tapered protrusion 36c from the distal end direction of the substrate-side plunger 36 toward the wiring substrate P, and therefore, the load does not act on the conductive cylinder 34, and the load is applied to the pressing force F₂There is no effect.

As described above, if the contact pin 3A according to the second embodiment is used, the position where the tip portion 35c contacts a part of the terminal 4a and the position where one end portion 37a of the spring 37 contacts the root portion 35d can be fixed. This can stably and strongly ensure a moment (force) based on two forces generated by the action point and the reaction pointAn even moment). That is, the contact pin 3A of the second embodiment passes through the distance L that will generate the moment of the two forces₁The distance is fixed at the maximum distance, and the unevenness caused by couple can be restrained.

The contact pin 3 according to the second embodiment can be set to the distance L described above₁A pressing force F generated by the moment of the force generated by the above-mentioned rotational force when the maximum distance is reached₂The side portion of the substrate-side large-diameter portion 36a is pushed toward the inner wall surface of the conductive tube 34. That is, the contact load of the side portion of the substrate-side large diameter portion 36a is stabilized and increased. Thus, the contact pin 3A according to the second embodiment can realize insulation of the current-carrying path for preventing the formation of the electrical connection without using a special shape such as the above-described elastic deformation portion.

In addition, even in the contact pin 3A of the second embodiment, the same configuration as the plungers 31A to 31D shown in fig. 10 to 13 can be applied to the terminal side small diameter portion 35a of the terminal side plunger 35. Thereby, the same effects as those exhibited by the plungers 31A to 31D shown in fig. 10 to 13 can be obtained.

In the present embodiment, the spring 37 applied to the contact pin 3A may be freely rotatable, only one end 37a of the spring 37 may be fixed in advance, and one end 37a and the other end 37b of the spring 37 may be fixed in advance. However, the arrangement shown in fig. 16 is made such that the phase is shifted by 180 degrees so that the distance L is set to be equal to the above-mentioned distance L₁Becomes the maximum distance.

Next, the use and operation of the socket 1 for electronic components including the contact pin 3A will be described with reference to fig. 2 and 3, and fig. 18A and 18B. In fig. 3, the contact pin 3 is replaced with a contact pin 3A.

Fig. 18A and 18B are explanatory views showing a usage state of the contact pin of fig. 14. Specifically, fig. 18A and 18B are main-part cross-sectional explanatory views showing the operation of the contact pins 3A when the electronic component socket 1 is mounted on the wiring board P and the electronic component is accommodated in the accommodation portion. As shown in fig. 2 and 3, first, the socket 1 for an electronic component is disposed on the wiring substrate P. At this time, as shown in fig. 18A, the lower surface of the bottom plate 7 shown in fig. 3 is carried on the upper surface of the wiring substrate P, and the contact portion of the front end of the substrate-side plunger 36 is pressed against the connection pad 9 of the wiring substrate P.

In this state, as shown in fig. 2, the IC package 4 to be tested is accommodated in the accommodating portion 5 of the housing 2 as indicated by arrow B. At this time, the IC package 4 is held by a mechanical device such as a robot arm by suction or the like, transferred to the socket 1 for electronic component, and stored in the storage section 5. Thereafter, the IC package 4 is fixed by closing the socket cover not shown.

At this time, as shown in fig. 18B, the IC package 4 is pushed down as indicated by an arrow C in accordance with the closing operation of the socket cover. Then, the solder balls 8 arranged in a grid-like manner on the lower surface of the IC package 4 push the front end portion 35c of the terminal-side plunger 35 in. At this time, the terminal-side plunger 35 is pressed against the biasing force of the spring 37 shown in fig. 15, and the entire conductive cylinder 34 is lowered in the arrow C direction and contracted. This allows the terminals 4a of the IC package 4 and the connection portion of the wiring board P to be electrically connected. At this time, the pressing force F is applied to the inside of the contact pin 3A₂The current flows through a path of the terminal-side plunger 35 → the conductive cylinder 34 → the substrate-side plunger 36.

Accordingly, in the contact pin 3A having the movable portion, it is possible to prevent damage such as insulation of a member assumed as a current passage, and current flowing and blowout of the spring 37 not assumed as the current passage. Although the case of using the contact pin 3A has been described, the same effects can be obtained also in the case of using the contact pin 3.

In this state, the IC package 4 is stored in the socket 1 for electronic components, and a predetermined test is performed for, for example, 20 to 30 seconds, and if the test is completed, the socket cover is opened, the IC package 4 is pulled out, and the IC package 4 is conveyed to the storage position by a robot arm or the like, and a series of test operations are completed. Further, the mechanical contact property of the conductive member electrically connecting the terminal of the IC package 4 and the connection portion of the wiring substrate P can be improved, the resistance value can be stabilized, and a predetermined test can be performed on the electronic component.

Description of the reference numerals

1 … socket for electronic component

2 … frame body

3. 3A … contact pin

4 … IC Package (electronic parts)

4a … terminal

5 … accommodating part

6 … support plate

9 … connection pad (connection part of wiring board)

31 … plunger

31a … substrate-side small-diameter portion

31b … terminal side large diameter part

31c, 35c … front end

32. 34 … conductive cylinder

33. 37, 38 … spring

33a, 37a, 38a …

33b, 37b, 38b … on the other end

35 … terminal side plunger

35a … terminal side small diameter part

35b … terminal-side large-diameter portion

36 … substrate side plunger

P … wiring substrate

Claims

1. A contact pin for electrically connecting an electronic component to a wiring board, the contact pin comprising:

a conductive cylinder having an opening at one end and formed in a cylindrical shape;

a plunger including a substrate-side small diameter portion and a terminal-side large diameter portion, the substrate-side small diameter portion being provided on one end portion side and being brought into contact with an inner wall surface of the conductive cylinder to be electrically connected to the connection portion of the wiring substrate by being inserted into the opening of the conductive cylinder; the terminal-side large diameter portion is provided on the other end portion side and has a leading end portion that contacts a portion of the terminal of the electronic component; and

a spring having one end portion abutting on a root portion of the terminal-side large-diameter portion and the other end portion abutting on an opening peripheral edge of the conductive cylinder, and contracting by being pressed by the electronic component,

in a state where the electronic component is pressed, a position where a tip portion of the terminal-side large diameter portion of the plunger contacts a part of the terminal of the electronic component and a position where one end portion of the spring abuts against a root portion of the terminal-side large diameter portion are located on a diagonal line of the terminal-side large diameter portion where a rotational force is generated by a force of the terminal pushing the tip portion and a force of the spring pushing back the root portion.

2. A contact pin for electrically connecting an electronic component to a wiring board, the contact pin comprising:

a conductive cylinder having both ends opened and formed in a cylindrical shape;

terminal-side plungers and substrate-side plungers held at both ends of the conductive cylinder and partially inserted into the conductive cylinder, the terminal-side plungers being in contact with terminals of the electronic component, the substrate-side plungers being in contact with and electrically connected to the connection portions of the wiring substrate; and

a spring that is compressed by the electronic component being pressed by applying a biasing force in a direction of separating the terminal-side plunger and the substrate-side plunger in the conductive cylinder,

the terminal side plunger includes a terminal side small diameter portion that is engaged with an inner wall surface of the conductive cylinder in a state of being inserted into the conductive cylinder and abuts against one end portion of the spring at a root portion, and a terminal side large diameter portion that is provided in a state of protruding from the conductive cylinder and has a leading end portion that contacts a part of a terminal of the electronic component,

in a state where the electronic component is pressed, a position where a tip portion of the terminal-side large diameter portion of the terminal-side plunger contacts a part of a terminal of the electronic component and a position where one end portion of the spring abuts against the root portion of the terminal-side small diameter portion of the terminal-side plunger are located on a diagonal line of the terminal-side plunger where a rotational force is generated by a force of the terminal pressing the tip portion and a force of the spring pushing back the root portion.

3. Contact pin according to claim 1 or 2,

in a state where the electronic component is pressed and the spring is contracted, a phase between one end of the spring and the other end of the spring is shifted by 180 degrees.

4. Contact pin according to claim 3,

the base portion abutting against one end portion of the spring has an inclined surface, and as the electronic component is pressed, the one end portion of the spring slides on the inclined surface and is positioned in abutment against the base portion.

5. Contact pin according to claim 4,

a hole is provided in the inclined surface of the root portion at a position abutting against the root portion, and the one end portion is inserted into the hole and positioned.

6. Contact pin according to claim 3,

a hole is provided at a position where one end portion of the spring abuts against the root portion, and the one end portion of the spring is fixed to the hole in advance.

7. A socket for an electronic component includes:

a frame body having a housing section for electronic components electrically connected to the wiring board; and

a plurality of contact pins which are respectively inserted into a plurality of insertion holes of a support plate provided below the housing portion in the frame body and electrically connect terminals of the electronic component and connection portions of the wiring substrate,

the socket for electronic components is characterized by comprising the contact pin according to any one of claims 1 to 6 as the contact pin.