JP7817566B2 - Circuit Board Socket - Google Patents

Description

The present invention relates to a socket for a circuit board, and more specifically to a socket for a circuit board that, when mounted on the circuit board, provides elastic connection between the circuit board and the socket's contacts.

Conventional methods for mounting electronic components such as semiconductor devices on circuit boards include fixing them to the board by soldering, and fixing them by contacting an elastic member with the board electrodes. The latter mounting method uses elastic force to press the contact points on the electronic component against the circuit board, achieving electrical continuity between the electronic component and the circuit board. When connecting an electronic component to a circuit board via a socket, the contacts in the socket elastically contact the circuit board, ensuring good contact.

Patent Document 1 describes how contact pins 15 serving as contacts are inserted through a pressure plate 26 in the socket body 13 of the IC socket 11 and press-fit into press-fit holes 13a. The contact pins 15 are designed so that their positions do not shift when they come into contact with the solder balls 12b of the IC package 12.

Japanese Patent Application Laid-Open No. 2000-311756

In Patent Document 1, if an attempt is made to secure the contact pins 15 (contactors) to the board electrodes by bringing an elastic member into contact with them in order to achieve electrical continuity between the IC package 12 (electronic component) and the circuit board, the resulting elastic force may act on the pressure plate 26 (board) via the contactors, causing deformation of the board. If this deformation is significant, the position of the contactors may be displaced due to board deformation, potentially causing the contactors to come into contact with areas of the IC package 12 (electronic component) where they should not be (miscontact).

The present invention aims to provide a socket for circuit boards that has a simple configuration and can prevent accidental contact due to reaction forces acting on the resilient contacts.

A socket for a circuit board comprising: a plurality of contacts; a contact fixing substrate that fixes and holds each of the plurality of contacts; a resilient contact holder substrate that is connected to the contact fixing substrate and has a plurality of through holes through which each of the plurality of contacts passes; and a plurality of resilient contacts that are arranged on the opposite side of the resilient contact holder substrate from the contact fixing substrate and that make contact with each of the plurality of contacts, wherein the resilient contacts make contact with the resilient contact holder substrate in the direction in which the resilient force of the resilient contacts acts.

A socket for a circuit board comprising: a plurality of contacts; a contact fixing substrate that fixes and holds each of the plurality of contacts; a plurality of contact elastic sections formed by elastically deforming the lower portions of the plurality of contacts; and a contact elastic section pressing substrate that is connected to the contact fixing substrate and has a plurality of through holes through which each of the plurality of contacts passes. The contact elastic sections are positioned on the opposite side of the contact elastic section pressing substrate from the contact fixing substrate, and come into contact with the contact elastic section pressing substrate in the direction in which the elastic force of the contact elastic sections acts.

The above configuration allows for a simple circuit board socket configuration that prevents accidental contact between the contacts and the electronic device due to reaction forces acting on the resilient contacts.

FIG. 1 is a perspective view showing an overall structure in which a circuit board socket and a circuit board according to an embodiment of the present invention are joined together. FIG. 2 shows an exploded view of the circuit board socket of FIG. FIG. 3(a) is a cross-sectional view showing insertion mounting using a conventional contactor fixing substrate for comparison, and FIG. 3(b) is a cross-sectional view showing a problem that occurs when insertion mounting using a conventional contactor fixing substrate is modified so that an elastic member is brought into contact with and fixed to a circuit board for comparison. 4A and 4B are diagrams showing a portion of a cross section along the arrangement of contacts of the circuit board socket of FIG. 2, where FIG. 4A shows the state before the contacts come into contact with the printed circuit board, and FIG. 4B shows the state after the contacts have come into contact with the printed circuit board. Figure 5 shows a side cross-sectional view of a circuit board socket according to another embodiment of the present invention, where Figure 5(a) is a side cross-sectional view of the circuit board socket according to another embodiment of the present invention in a state before contact with the circuit board, and Figure 5(b) is a side cross-sectional view of the circuit board socket according to another embodiment of the present invention in a state after contact with the circuit board. Figure 6 is a diagram showing contact at two points between a contact and a contact spring in an embodiment of the present invention, where Figure 6(a) shows a schematic view of one side along the arrangement of the contacts, Figure 6(b) shows a schematic view of the other side along the arrangement of the contacts, Figure 6(c) shows an enlarged cross-sectional view in the direction of line VIc, and Figure 6(d) shows an enlarged cross-sectional view in the direction of line VId. Figure 7 is a diagram showing contact at two points between a contact and a contact spring in an embodiment of the present invention, where Figure 7(a) shows a schematic view of one side along the arrangement of the contacts, Figure 7(b) shows a schematic view of the other side along the arrangement of the contacts, Figure 7(c) shows an enlarged cross-sectional view in the direction of line VIIc, and Figure 7(d) shows an enlarged cross-sectional view in the direction of line VIId. Figure 8 is a diagram showing contact at two points between a contact and a contact spring in an embodiment of the present invention, where Figure 8(a) shows a schematic view of one side along the arrangement of the contacts, Figure 8(b) shows a schematic view of the other side along the arrangement of the contacts, Figure 8(c) shows an enlarged cross-sectional view in the direction of line VIIIc, and Figure 8(d) shows an enlarged cross-sectional view in the direction of line VIIId. Figure 9 shows contact at two points between a contact and a contact spring in an embodiment of the present invention, where Figure 9(a) shows a schematic view of one side along the arrangement of the contacts, Figure 9(b) shows a schematic view of the other side along the arrangement of the contacts, Figure 9(c) shows an enlarged cross-sectional view in the direction of line IXc, and Figure 9(d) shows an enlarged cross-sectional view in the direction of line IXd. Figure 10 is a diagram showing contact at two points between a contact and a contact spring in an embodiment of the present invention, where Figure 10(a) shows a schematic view of one side along the arrangement of the contacts, Figure 10(b) shows a schematic view of the other side along the arrangement of the contacts, Figure 10(c) shows an enlarged cross-sectional view in the Xc line direction, and Figure 10(d) shows an enlarged cross-sectional view in the Xd line direction. 11A and 11B are graphs showing the insertion loss characteristics when the contactor according to the embodiment of the present invention and the contact spring contact each other at one or two points, with FIG. 11A showing the insertion loss characteristics when the conventional contactor and the contact spring contact each other at one point, and FIG. 11B showing the insertion loss characteristics when the contactor and the contact spring contact each other at two points.

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

(Embodiment 1)
<Outline of circuit board sockets>
Fig. 1 is a perspective view showing the appearance of a circuit board socket according to one embodiment of the present invention, mounted on a circuit board. In Fig. 1, the circuit board socket 10 includes a contact fixing substrate 12, the four peripheral side surfaces of which form the outer shell of the circuit board socket 10. The circuit board socket 10 has a resilient contact housing member 16 disposed below the contact fixing substrate 12, and is connected to a circuit board 2 via this substrate 16. A cover 9 is provided above the contact fixing substrate 12, with a portion of the cover 9 fixed by the contact fixing substrate 12. A guide 8 for guiding an electronic device is located inside the cover 9, and an electronic device (not shown) is mounted inside the cover 9, electrically connecting the electronic device to the circuit board socket 10.

The upper end portions of the contacts 11 are arranged on the upper surface of the slider 7 and can be connected to the electrical contacts of an electronic device. While only one row is shown in Figure 1 for simplicity, in reality the upper end portions of the contacts 11 extend across the entire surface of the slider 7. An elastic contact holder substrate 14 is provided below the contactor fixing substrate 12, as will be described in detail later in Figure 2.

<Detailed configuration of the circuit board socket>
FIG. 2 is an exploded perspective view of the circuit board socket shown in FIG. 1, and also shows the positional relationship between the electronic device 1 and the circuit board 2.

The circuit board socket 10 is composed of three board layers: a contact fixing board 12, a resilient contact presser board 14, and a resilient contact accommodating member 16. The upper portions (excluding the upper ends) of the contacts 11 are held fixed by the contact fixing board 12. As shown in Figure 3, a plurality of contacts 11 are arranged in one direction. For simplicity's sake, only two rows of contacts are shown in the circuit board socket of this embodiment. Each of the contacts 11 held by the contact fixing board 12 is positioned to pass through a corresponding through-hole 18 (see Figure 4) in the resilient contact presser board 14. Furthermore, the contacts 11 are positioned so that their lower ends come into contact with resilient contacts 15 arranged in corresponding holes in the resilient contact accommodating member 16.

In the above arrangement, the upper end of each contactor 11 can make electrical contact with the leads (not shown) of the electronic device 1 mounted on the circuit board socket 10, and the lower end of each contactor 11 can make electrical contact with the resilient contactor 15. As will be described later, the resilient contactor 15 can make electrical contact with a predetermined connection portion of the circuit board 2, thereby enabling electrical continuity between the electronic device 1 and the circuit board 2. Furthermore, because the contactor 11 is supported by the contactor fixing substrate 12, the contact height of the upper end of the contactor can be maintained constant, allowing stable contact between the leads of the electronic device 1 and the contactor 11. Note that, although a coil spring is used as the resilient contactor 15 in this embodiment, this is not a limitation.

The circuit board socket with the above-described configuration is a type of fixation method that involves contacting an elastic member with the board electrodes. That is, in this circuit board socket, the contactors 11 are fixed by the contactor fixing substrate 12, and the reactive force from the circuit board 2 can act on the contactor fixing substrate 12 when the elastic contactors 15 contact the circuit board 2. In this configuration, the reactive force can deform the contactor fixing substrate 12, potentially resulting in incorrect contact with the electronic device attached to the socket. In contrast, in an embodiment of the present invention, as described above, the elastic contactor pressing substrate 14 is provided between the contactor fixing substrate 12 and the elastic contactor housing member 16, and the elastic contactors 15 contact the lower end of the elastic contactor pressing substrate 14. The elastic contactor pressing substrate 14 then absorbs the reactive force from the circuit board 2 when the elastic contactors 15 contact the circuit board 2, preventing this reactive force from being directly applied to the contactor fixing substrate 12. Furthermore, by providing a space between the elastic contact holder substrate 14 and the contact fixing substrate 12, the reaction force is prevented from being exerted on the contact fixing substrate 12, which fixes and holds the contacts 11. This configuration will be explained in detail below.

Before explaining the socket structure of this embodiment that prevents deformation, we will explain how the contactor fixing substrate is deformed by the reaction force of the resilient contacts. Figures 3(a) and (b) are cross-sectional views showing a socket structure according to a comparative example.

As shown in Figure 3(a), in the socket structure of the comparative example, the contactor 31 is press-fitted and fixed to the contactor fixing substrate 33. The upper end of the contactor 31 is positioned to sandwich the external contact 32 of the electronic device 5, thereby enabling electrical connection between the electronic device 5 and the contactor 31.

On the other hand, as shown in Figure 3(b), the lower end of the contactor 31 connects to the resilient contactor 34 (the resilient contactor housing member is not shown), and the resilient contactor 34 contacts the circuit board 6. As the resilient contactor housing member connects to the circuit board 6, a reaction force from the resilient contactor 34 acts via the contactor 31 on the contactor fixing substrate 33 to which the contactor 31 is fixed. This reaction force from the resilient contactor 34 causes the contactor fixing substrate 33 to deform toward the electronic device 5, as shown in Figure 3(b). As a result, the upper end of the contactor 31 becomes misaligned, causing it to come into erroneous contact with the electronic device 5, which can result in poor electrical contact or damage to the electronic device 5. Note that the deformation of the contactor fixing substrate 33 is shown simply, and in this example, the arrangement of three contactors 31 shows that the central contactor 31 in the arrangement deforms the most.

<Deformation prevention structure of contactor fixing substrate according to the embodiment>
4(a) and (b) are diagrams showing a part of a cross section along the arrangement of the contacts 11 of the three substrates 12, 14, and 16 shown in FIG. 2, and only two of the arrangement of the contacts 11 are shown.

As shown in Figures 4(a) and (b), the circuit board socket 10 has three substrate layers: a contact fixing substrate 12, a resilient contact presser substrate 14, and a resilient contact accommodating member 16. The resilient contacts 15 are positioned on the opposite side of the resilient contact presser substrate 14 from the contact fixing substrate 12, and contact the resilient contact presser substrate in the direction in which the resilient force of the resilient contacts 15 acts. The upper portions of the contacts 11 are fixed by contact-substrate fixing portions 13 provided in corresponding holes in the contact fixing substrate 12, and are arranged to be relatively movable via the resilient contact presser substrate 14 and its through-holes 18. The lower ends of the contacts 11 contact the contact-resilient contact portions 17 of the resilient contacts 15 within the holes in the resilient contact accommodating member 16. As described above, the contacts 11 are fixed to the contact fixing substrate 12, but are not fixed to the resilient contact presser substrate 14 or the resilient contact accommodating member 16. Furthermore, the upper ends of the resilient contacts 15 are larger in size than the diameter of the through-holes 18, so that the upper ends of the resilient contacts 15 come into contact with the lower surface of the resilient contact presser substrate 14. However, the present invention is not limited to this, and the upper tapered portions of the resilient contacts 15 may fit into the through-holes 18, so that the tapered portions come into contact with the resilient contact presser substrate 14. Alternatively, a recess for receiving the upper portions of the resilient contacts 15 may be formed in the lower portion of the resilient contact presser substrate 14, so that the upper portions of the resilient contacts 15 come into contact with the resilient contact presser substrate 14 within this recess. Furthermore, a protrusion for making contact with the upper portions of the resilient contacts 15 may be formed in the lower portion of the resilient contact presser substrate 14, so that the upper portions of the resilient contacts 15 come into contact with the resilient contact presser substrate 14 at this protrusion.

Figure 4(a) shows the state before the circuit board socket 10 of this embodiment is connected to the circuit board 2 (connection portion 2a), in which the elastic contacts 15 are in an expanded state and protrude below the circuit board socket 10. In contrast, Figure 4(b) shows the state after the circuit board socket 10 is connected to the circuit board 2 (connection portion 2a), in which the elastic contacts 15 are in a contracted state due to their connection to the circuit board 2 (connection portion 2a). In this contracted state, the elastic contacts 15 apply a reaction force from the circuit board 2 to the elastic contact holddown board 14 via the upper ends of the elastic contacts 15.

In this embodiment, deformation of the contactor fixing substrate 12 due to the reaction force is prevented by providing a space 19 above the resilient contactor presser substrate 14. Specifically, a recess is provided in a region above the resilient contactor presser substrate 14 that corresponds to the arrangement range of the contacts 11. This recess forms a space 19 between the contactor fixing substrate 12 and the resilient contactor presser substrate 14. This prevents the contactor fixing substrate 12 from being damaged, even if the resilient contactor presser substrate 14 is deformed toward the contactor fixing substrate 12 due to the reaction force of the resilient contacts 15. As a result, it is possible to prevent the contactors 11 from coming into contact with the electronic device 1 and damage to the electronic device 1. Furthermore, since this structure is simpler than a structure in which a pressure receiving portion is provided within a through-hole, the contactors can be arranged at a high density. While this embodiment provides a recess in a region above the resilient contactor presser substrate 14 that corresponds to the arrangement range of the contacts 11, this is not limited to this, and a recess may be provided on the contactor fixing substrate 12 side.

The size of this space 19 is determined so that the contactor fixing substrate 12 and the elastic contactor pressing substrate 14 do not come into contact with each other, even if the elastic contactor pressing substrate 14 is deformed toward the contactor fixing substrate 12 due to the reaction force from the elastic contactor 15.

(Embodiment 2)
<Outline of Circuit Board Socket According to Another Embodiment>
A circuit board socket 20 according to another embodiment will now be described. The circuit board socket 20 is composed of contacts 21, a contact fixing substrate 22, a contact elastic portion holding substrate 24, contact elastic portions 25, and a contact elastic portion accommodating member 26. The contact fixing substrate 22 has a contact-to-substrate fixing portion 23 for fixing the contacts 21. A contact elastic portion 25 is provided below the contacts 21, continuing from the contacts 21 and forming a part of the contacts 21. The contact elastic portion accommodating member 26 has an accommodating portion 27 formed to receive the contact elastic portion 25. The upper end of the contact elastic portion 25 contacts the lower end of the contact elastic portion holding substrate 24. The contact elastic portion holding substrate 24 then bears the reaction force from the circuit board 4 when the contact elastic portion 25 contacts the circuit board 4, preventing this reaction force from being directly applied to the contact fixing substrate 22. Furthermore, by providing a space between the contact elastic portion holding board 24 and the contact fixing board 22, the reaction force is prevented from being exerted on the contact fixing board 22 which fixes and holds the contacts 21. Note that a description of parts that overlap with the above-mentioned circuit board socket 10 will be omitted.

<Detailed Configuration of Circuit Board Socket According to Another Embodiment>
Figure 5 is a cross-sectional view of a circuit board socket 20 according to another embodiment of the present invention, showing a detailed configuration of the circuit board socket 20 that differs from the circuit board socket 10 described above. Figure 5(a) is a side cross-sectional view of the circuit board socket 20 according to another embodiment of the present invention before contact with the circuit board 4 (connection portion 4a). In this state, the contactor elastic portions 25 are in an expanded state and protrude downward from the circuit board socket 10. In contrast, Figure 5(b) shows the state after connection with the circuit board 4 (connection portion 4a). In this state, the contactor elastic portions 25 are in a contracted state due to connection with the circuit board 4 (connection portion 4a). In this contracted state, the contactor elastic portions 25 apply a reaction force from the circuit board 4 (connection portion 4a) to the contactor elastic portion holding substrate 24 via the upper ends of the contactor elastic portions 25. That is, the contact elastic portion 25 is arranged on the opposite side of the contact elastic portion pressing substrate 24 from the contact fixing substrate 22, and contacts the contact elastic portion pressing substrate 24 in the direction in which the elastic force of the contact elastic portion 25 acts.

In this embodiment, unlike the circuit board socket 10 described above, the contactor 21 itself doubles as a resilient contactor. The lower portion of the contactor 21, the contactor resilient portion 25, is resiliently deformed and formed into a helical spring shape, as shown in FIG. 5(a). When the contactor resilient portion 25 contracts, as shown in FIG. 5(b), the reaction force of the contactor resilient portion 25 presses the contactor 21 against (the connection portion 4a) of the circuit board 4, electrically connecting the contactor 21 to the circuit board 4. At this time, the lower portion of the contactor resilient portion 25 is fitted into and accommodated in the accommodation portion 27 provided in the contactor resilient portion accommodation member 26, restricting downward movement. This prevents the contactor 21, pressed against (the connection portion 4a) of the circuit board 4, from moving away from (the connection portion 4a) of the circuit board 4, thereby preventing the electrical connection from being released. Furthermore, the contactor 21, pressed against (the connection portion 4a) of the circuit board 4, can be prevented from coming into contact with the circuit board 4 at any point other than the lower end. The contactor elastic portion 25 is not particularly limited as long as it has an elastic shape. For example, it may be spring-shaped, and more specifically, it may be helical spring-shaped or bow spring-shaped.

In this embodiment, deformation of the contactor fixing substrate 22 due to the reaction force is prevented by providing a space 29 above the contactor elastic portion holding substrate 24. Specifically, a recess is provided in an area above the contactor elastic portion holding substrate 24 that corresponds to the arrangement range of the contacts 21. This recess forms a space 29 between the contactor fixing substrate 22 and the contactor elastic portion holding substrate 24. As a result, even if the contactor elastic portion holding substrate 24 deforms toward the contactor fixing substrate 22 due to the reaction force from the contactor elastic portion 25, this deformation can be prevented from affecting the contactor fixing substrate 22. As a result, it is possible to prevent the contactors 21 from making incorrect contact with the electronic device 3 and damage to the electronic device 3. Here, in this embodiment, a recess is provided in an area above the contactor elastic portion holding substrate 24 that corresponds to the arrangement range of the contacts 21, but this is not limited to this, and a recess may be provided on the contactor fixing substrate 22 side.

The size of this space 29 is determined so that the contactor fixing substrate 22 and the contactor elastic portion pressing substrate 24 do not come into contact with each other, even if the contactor elastic portion pressing substrate 24 is deformed toward the contactor fixing substrate 22 due to the reaction force from the contactor elastic portion 25.

<Two contact points: contact piece and contact spring>
Figures 6 to 10 show contacts and resilient contacts (contact springs) according to other embodiments of the present invention, each having contact portions at two locations. Figures 6(a) to 10(a) show schematic views of one side along the arrangement of the contacts, and Figures 6(b) to 10(b) show schematic views of the other side along the arrangement of the contacts. Figures 6(c) to 10(c) show enlarged cross-sectional views along lines VIc to Xc, respectively, and Figures 6(d) to 10(d) show enlarged cross-sectional views along lines VId to Xd, respectively. Note that common parts of Figures 6 to 10 will be described using Figure 6 as a representative, and descriptions of other parts will be omitted.

As shown in Figures 6(a) and (b), in this embodiment, the contactor 41 and the resilient contactor 45 have contact portions 48 and 49 at the top and bottom of the resilient contactor 45, respectively. As shown in Figure 6(c), at the contact portion 48 with the resilient contactor 45, the two halves of the contactor 41 make point contact at two locations. This ensures that the contactor 41 makes reliable contact with the resilient contactor 45 at the contact portion 48. In contrast, as shown in Figure 6(d), at the contact portion 49, each of the two halves of the contactor has a semicircular cross section, and the arc portion makes point contact with the resilient contactor 45. Note that the contact between the contactor 41 and the resilient contactor 45 at the contact portion 48 is such that the load at the contact is applied horizontally, and the reaction force of the resilient contactor 45 does not push the contactor 41 upward at the contact portion 48. This prevents the reaction force of the resilient contactor 45 from pushing the contactor 41 upward at the contact portion 48, thereby preventing deformation of the contactor fixing substrate (not shown). Furthermore, as shown in FIG. 6(a), the contactor 41 has a width corresponding to the diameter of the resilient contactor 45. That is, as shown in FIG. 6(c), the contactor 41 has a cross-sectional shape that contacts the resilient contactor 45 at the contact portion 48, which is farther from the tip of the contactor 41 than the at least two contact portions 48, 49. This ensures that the contactor 41 reliably contacts the resilient contactor 45 at the contact portion 48. In this embodiment, this configuration is achieved by tapering the contactor 41.

In this way, when the contactor 41 and the resilient contactor 45 have contact portions 48 and 49 at the top and bottom of the resilient contactor 45, respectively, the occurrence of stubs can be suppressed compared to when there is only one contact portion, and as explained in the next section, the insertion loss characteristics of signals input from the electronic device to the circuit board can be improved.

As shown in Figure 7(c), the contactor 51 splits into three pieces near the contact portion 58, one of which has a curved portion 52 at its tip that is convex in longitudinal cross section, and this curved portion 52 makes point contact with the resilient contactor 55. This curved portion 52 ensures that the contactor 51 makes reliable contact with the resilient contactor 55 at the contact portion 58.

As shown in Figure 8(c), one of the two halves of the contactor 61 has a protrusion 62 formed by bending a portion of the contactor in the longitudinal direction so that the contactor 61 makes point contact with the resilient contactor 65 at the contact portion 68 along the length of the contactor 61. This protrusion 62 ensures that the contactor 61 makes reliable contact with the resilient contactor 65 at the contact portion 68.

As shown in Figure 9(c), both of the two halves of the contactor 71 have protrusions 72 and 73 formed by bending a portion of the contactor in the longitudinal direction, so that the contactor 71 makes point contact with the resilient contactor 75 at the contact portion 78 along the length of the contactor 71. Meanwhile, as shown in Figures 9(a) and (d), at the contact portion 79, the tip of the contactor 71 has a twisted shape while being split into two. This allows the tip of the contactor 71 to be pressed against the resilient contactor 75 with greater force than if it were simply split into two, resulting in more reliable contact between the contactor 71 and the resilient contactor 75 at the contact portion 79.

As shown in Figure 10(c), the contactor 81 is divided into three parts near the contact portion 88, and has a semicircular cross section. One of the three parts of the contactor 81 makes point contact with the elastic contactor 85 at the contact portion 88.

As shown in Figures 7(d) to 8(d) and Figure 10(d), contact portions 59 to 69 and 89 are the same as those in Figure 6(d).

In this way, by providing multiple contact points at the contact portion between the contactor and the resilient contactor, and by firmly pressing the contactor against the resilient contactor, it is possible to ensure high and reliable conductivity between the contactor and the resilient contactor, further reducing the occurrence of stubs. Note that, although this embodiment illustrates two contact points between the contactor and the resilient contactor, there may be three or more contact points.

<Differences in insertion loss due to differences in the number of contact points between the contact and the contact spring>
11A and 11B are graphs showing insertion loss characteristics for an input signal from an electronic device when the contactor and contact spring according to an embodiment of the present invention have one or two contact points. Fig. 11A shows the insertion loss characteristics for a conventional contactor and contact spring having one contact point, with the vertical axis representing insertion loss (dB) and the horizontal axis representing frequency (Hz). Fig. 11B shows the insertion loss characteristics for a contactor and contact spring according to an embodiment of the present invention having two contact points, with the vertical axis representing insertion loss (dB) and the horizontal axis representing frequency (Hz). In this embodiment, an S-parameter measurement simulation was performed, and it was confirmed that, for all four input signal frequency steps, the insertion loss dropped around 2 GHz for single-contact, but dropped around 5 GHz for two-contact.

Looking at Figure 11(a), we can see that at each of the four steps, a sudden increase in insertion loss occurs for the input signal at a frequency of around 2 GHz. When a conventional contactor and contact spring have a single contact point, the spring portion exists above the contact point, and this part acts as a stub, causing the signal to flow from the contact point, reflect at the free end, and return to the contact point, adversely affecting the original signal. This is thought to be the cause of the increase in insertion loss.

In contrast, Figure 11(b) shows that the insertion loss at frequencies around 2 GHz is eliminated. Furthermore, up to a frequency of 4 GHz, the waveform is smooth, suppressing the occurrence of stubs and improving insertion loss characteristics.

This configuration allows for a nearly stub-free environment (free from signal degradation factors), leading to improved insertion loss.

DESCRIPTION OF SYMBOLS 1, 3, 5 Electronic device 2, 4, 6 Circuit board 7 Slider 8 Guide 9 Cover 10 Circuit board socket 11 Contactor 12 Contactor fixing board 13 Contactor-board fixing portion 14 Resilient contactor pressing board 15 Resilient contactor 16 Resilient contactor accommodating member 17 Contactor-resilient contactor contact portion 18 Through holes 19, 29 Space portion 20 Circuit board socket 21 Contactor 22 Contactor fixing board 23 Contactor-board fixing portion 24 Contactor resilient portion pressing board 25 Contactor resilient portion 26 Contactor resilient portion accommodating member 27 Accommodating portion 31 Contactor 32 External contact 33 Contactor fixing board 34 Resilient contactor 41, 51, 61, 71, 81 Contactor 45, 55, 65, 75, 85 Resilient contactor 48, 58, 68, 78, 88 Contact portions 49, 59, 69, 79, 89 Contact portion 52 Convex curved surface portions 62, 72, 73 Convex portion

Claims (12)

A socket for a circuit board,
A plurality of contacts;
a contact fixing substrate that fixes and holds each of the plurality of contacts;
an elastic contact pressing substrate connected to the contact fixing substrate and having a plurality of through holes through which the plurality of contacts pass;
a plurality of elastic contacts arranged on the opposite side of the elastic contact holder substrate from the contact fixing substrate, the elastic contacts being in contact with the plurality of contacts, respectively;
Equipped with
The socket for a circuit board, wherein the elastic contacts come into contact with the elastic contact pressing board in a direction in which the elastic force of the elastic contacts acts. The circuit board socket according to claim 1, characterized in that a space is provided between the area of the elastic contact presser substrate corresponding to the arrangement of the multiple contacts and the contact fixing substrate. The circuit board socket according to claim 2, further comprising an elastic contact housing member having a plurality of holes each containing one of the elastic contacts. A socket for a circuit board according to any one of claims 1 to 3, characterized in that the elastic contact is a coil spring and makes contact with the contact at least two contact portions. A socket for a circuit board as described in claim 4, characterized in that each of the at least two contact portions contacts the contactor at at least two locations. The circuit board socket described in claim 4, characterized in that the contactor has a cross-sectional shape that allows the contactor to contact the coil spring at the contactor farther from the tip of the contactor out of the at least two contact portions. The socket for a circuit board according to claim 4, characterized in that the contactor has a curved portion at the tip that is convex in longitudinal cross section, thereby contacting the coil spring at at least one of the at least two contact portions. A socket for a circuit board as described in claim 4, characterized in that the contactor has at least one protrusion, thereby contacting the coil spring at at least one of the at least two contact portions. A socket for a circuit board as described in claim 4, characterized in that the tip of the contactor is split into two and twisted, so that at least one of the at least two contact portions contacts the coil spring. A socket for a circuit board,
A plurality of contacts;
a contact fixing substrate that fixes and holds each of the plurality of contacts;
a plurality of contact elastic portions formed by elastically deforming lower portions of the plurality of contacts;
a contact elastic portion holding substrate connected to the contact fixing substrate and having a plurality of through holes through which the plurality of contacts pass;
Equipped with
A socket for a circuit board, characterized in that the contact elastic portion is arranged on the opposite side of the contact elastic portion holding substrate from the contact fixing substrate, and contacts the contact elastic portion holding substrate in the direction in which the elastic force of the contact elastic portion acts. The socket for a circuit board according to claim 10, further comprising a contact elastic portion accommodating member having multiple accommodating portions that respectively accommodate the lower portions of the multiple contact elastic portions. A circuit board socket as described in claim 10 or 11, characterized in that a space is provided between the area of the contact elastic portion holding substrate corresponding to the arrangement of the multiple contacts and the contact fixing substrate.