Spring connector

Abstract

Provided is a spring connector capable of maintaining a necessary waterproof performance even in an application in which a movable pin slides repeatedly.　This spring connector comprises: a conductive tube; a conductive movable pin of which a tip side protrudes from an opening of the tube; a spring which is disposed in the tube and which biases the movable pin in an axial direction and causes the movable pin to protrude; a waterproofing elastic body which is disposed around the tip side of the movable pin protruding from the tube; and a housing recess for the waterproofing elastic body, wherein at least part of the outer peripheral side of the waterproofing elastic body housed in the housing recess comes into contact with the inner peripheral surface of the housing recess and the tip side outer peripheral surface of the movable pin is contacted in an annular manner at a plurality of sites on the inner peripheral side of the waterproofing elastic body in the axial direction of the movable pin.

Description

Spring Connector

[0001] The present invention relates to a spring connector.

[0002] In a conventional spring connector, when a liquid such as water penetrates inside, there is a risk of problems such as instability of electrical contact due to the surface tension of the liquid, corrosion, and short circuit. As a structure having waterproof performance inside with a single spring connector, there has been a case where an O-ring with a circular cross-section is installed around the movable pin.

[0003] Chinese Utility Model Registration Bulletin CN 211376992

[0004] In the above prior art, there has been a problem that wear and breakage of the O-ring occur in applications where the movable pin repeatedly slides, and the waterproof performance deteriorates significantly.

[0005] An example of the object of the present invention is to provide a spring connector capable of maintaining the required waterproof performance even in applications where the movable pin repeatedly slides. Other objects of the present invention will become apparent from the description herein.

[0006] One aspect of the present invention is a spring connector, including a conductive tube, a conductive movable pin whose tip side protrudes from the opening of the tube, a spring disposed inside the tube for axially biasing and protruding the movable pin, a waterproof elastic body disposed around the tip side of the movable pin protruding from the tube, and a storage recess for the waterproof elastic body. At least a part of the outer peripheral side of the waterproof elastic body stored in the storage recess contacts the inner peripheral surface of the storage recess and annularly contacts the outer peripheral surface of the tip side of the movable pin at a plurality of locations on the inner peripheral side of the waterproof elastic body in the axial direction of the movable pin.

[0007] According to the above aspect of the present invention, the required waterproof performance can be maintained even in applications where the movable pin repeatedly slides.

[0008] This is a longitudinal cross-sectional view of a spring connector 1 according to Embodiment 1 of the present invention. This is a longitudinal cross-sectional view of the spring connector 1 in its full stroke state (the state in which the movable pin is pushed in the most). This is a perspective view showing the external appearance of the spring connector 1. This is an enlarged cross-sectional view showing the waterproof structure portion of the spring connector 1. This is a side view showing the waterproof elastic body used in Embodiment 1. This is the same side cross-sectional view. This is the same front view. This is a partial cross-sectional front view showing the spring connector 1 mounted on a housing. This is a longitudinal cross-sectional view of a spring connector 1A according to Embodiment 2 of the present invention. This is an enlarged cross-sectional view showing the waterproof structure portion of the spring connector 1A. This is a side view showing the waterproof elastic body used in Embodiment 2. This is the same side cross-sectional view. This is the same front view. This is a partial cross-sectional front view of a spring connector 1B according to Embodiment 3 of the present invention, showing it mounted on a housing.

[0009] (Embodiment 1) A spring connector 1 according to Embodiment 1 of the present invention will be described with reference to Figures 1 to 6. As shown in these figures, the spring connector 1 includes a conductive movable pin 10, a conductive tube 20 that slidably houses the movable pin 10, a conductive sphere 30 and a coil spring 40 arranged inside the tube 20, and a conductive outer cap 50 fixed to the rear end of the tube 20. Furthermore, the spring connector 1 has a waterproof structure to prevent liquid from entering from the outside, and this waterproof structure includes an X-ring 60 as a waterproof elastic body arranged on the outer circumference of the tip side of the movable pin 10, and a storage cap 70 as a storage member that houses the X-ring inside and is arranged on the outer circumference of the tip side of the tube 20.

[0010] The conductive movable pin 10 is cylindrical and has a large-diameter portion 11 that can slide inside the tube 20 and a small-diameter portion 12 that can protrude from the tube 20. The movable pin 10 is made of, for example, a copper alloy with a metal plating layer such as Au plating on its surface. The tip of the movable pin 10, that is, the tip of the small-diameter portion 12, is, for example, hemispherical and constitutes one of the contacts of the spring connector 1. The rear end surface of the movable pin 10 is an inclined surface 13 that is tilted with respect to the axial direction of the movable pin 10, and a conductive sphere 30 is interposed between the inclined surface 13 and the coil spring 40.

[0011] The tube 20 is conductive (for example, made of the same material as the movable pin 10) and has a bottomless structure, that is, a cylindrical through-structure with openings at both ends. The inner circumferential surface of the tube 20 has a large-diameter surface 21 and a small-diameter surface 22. The large-diameter surface 21 slidably houses the large-diameter portion 11 of the conductive movable pin 10 and also houses the sphere 30 and the coil spring 40. The small-diameter surface 22 is located on the tip side of the tube 20 and prevents the conductive movable pin 10 from coming out. In other words, the small-diameter surface 22 is smaller in diameter than the large-diameter portion 11 of the movable pin 10 and larger in diameter than the small-diameter portion 12 of the movable pin 10, and passes through the small-diameter portion 12 in a movable state. The movable pin 10 is prevented from coming out of the tube 20 towards the tip side by the portion of the tube 20 that forms the boundary between the large-diameter portion 11 and the small-diameter portion 12 (the tapered stepped portion) abutting against the rear end side of the small-diameter surface 22 on the tube 20.

[0012] The conductive sphere 30 is, for example, a steel ball, but a sphere made of an insulating material with a metal-plated surface can also be used. The coil spring 40 is, for example, made by forming a coil from a common metal wire such as piano wire or stainless steel wire.

[0013] The outer cap 50 is conductive (for example, made of the same material as the tube 20) and has a closed bottom structure. The outer cap 50 is press-fitted and fixed to the rear end of the tube 20 with the large diameter portion 11 of the movable pin 10, the sphere 30, and the coil spring 40 inserted into the tube 20. The tip of the coil spring 40 abuts against the sphere 30, and the rear end abuts against the inner bottom surface 51 of the outer cap 50, thereby supporting the coil spring 40 and preventing it from falling out. A hole 52 for air venting is formed at the center of the bottom surface of the outer cap 50. The rear end surface 53 of the outer cap 50 is substantially planar and constitutes the pad that becomes the other contact of the spring connector 1.

[0014] The X-ring 60, acting as a waterproof elastic body, is positioned on the outer circumference of the small-diameter portion 12 of the movable pin 10, on the outside of the tip surface of the tube 20. The storage cap 70 has a storage recess 71 for housing the X-ring 60, a central hole 72 for passing through the small-diameter portion 12, and a mounting flange portion 73. It is press-fitted and fixed to the outer circumference of the tip of the tube 20 so as to house and cover the X-ring 60. Conductivity is not required for the storage cap 70, and it can be made of metal, resin, etc.

[0015] Figure 4 shows an enlarged view of the waterproof structure portion of the spring connector 1, and Figures 5A, 5B, and 5C show enlarged views of the X-ring. The X-ring 60 is an annular elastic body having a central hole 65 through which the small-diameter portion 12 of the movable pin 10 slides freely, and the cross-section of the annular portion is approximately X-shaped. That is, the X-ring 60 has a predetermined thickness in the axial direction of the movable pin 10, and a pair of annular protrusions 61, 62 and a recess 63 between them are formed on the inner circumferential surface, and a pair of annular protrusions 66, 67 and a recess 68 between them are formed on the outer circumferential surface. The X-ring 60 is stored in a compressed state inside the storage recess 71 of the storage cap 70 with the small-diameter portion 12 passing through the central hole 65. That is, it is positioned in a compressed state between the outer circumferential surface 12a of the small-diameter portion 12 of the movable pin 10 and the inner circumferential surface 71a of the storage recess 71. As a result, the X-ring 60 makes annular contact with the outer circumferential surface 12a of the small-diameter portion 12 at multiple points (two points in the illustrated case) in the axial direction of the movable pin 10, namely the annular protrusions 61 and 62. In addition, the movable pin 10 also makes annular contact with the inner circumferential surface 71a of the storage recess 71 at multiple points (two points in the illustrated case) in the axial direction of the movable pin 10, namely the annular protrusions 66 and 67. Although the small-diameter portion 12 needs to slide against the X-ring 60, the recess 63 between the annular protrusions 61 and 62 does not contact the small-diameter portion 12, thus reducing the contact area and improving waterproof performance, and not hindering the sliding of the small-diameter portion 12.

[0016] As shown in Figure 1, when no external force is applied to the movable pin 10 of the spring connector 1, the small diameter portion 12 is in its most protruding state (the reaction force of the coil spring 40 is greater than the frictional force between the small diameter portion 12 of the movable pin 10 and the X-ring 60). When the tip of the small diameter portion 12 is pressed by the electrode on the mating side, the coil spring 40 compresses, causing the small diameter portion 12 to retract and reach the full stroke state shown in Figure 2.

[0017] Since the X-ring 60 contacts the small-diameter portion 12 at multiple points in the axial direction of the movable pin 10, if the coil spring 40 simply contacts the rear end face of the movable pin 10, there is a concern that the movable pin 10 will be supported parallel to the axial direction, and electrical contact from the movable pin 10 to the inner wall of the tube 20 will not be obtained. For this reason, the rear end face of the movable pin 10 is made into an inclined surface 13, and a sphere 30 is interposed between the inclined surface 13 and the coil spring 40. This generates a component force in the direction that inclins the movable pin 10 with respect to the axial direction, and the movable pin 10 can be reliably brought into contact with the inner wall of the tube 20 with the required lateral pressure. In addition, by making the sphere 30 conductive, the sphere 30 also contributes to the electrical connection between the movable pin 10 and the tube 20. Note that the sphere does not have to be a perfect sphere; it may be a shape such as a cylinder with the end formed into a spherical surface.

[0018] Figure 6 shows an example of the implementation of the spring connector 1, illustrating a structure in which the spring connector 1 is attached to a housing 80 of an electronic device or the like, which has a stepped hole 81, with a waterproof gasket 82 interposed between them. The gasket 82 is fitted onto the outer circumference of the storage cap 70 of the spring connector 1 and is compressed by a flange portion 73 fixed to the housing 80 and positioned in the annular groove 81a of the stepped hole 81. By attaching the waterproof gasket 82 to the outer circumference of the storage cap 70 and attaching the spring connector 1 to the stepped hole 81, it is possible to prevent liquids such as water from entering the housing 80.

[0019] Figure 6 shows that the outer cap 50 of the spring connector 1 is connected to the electrode 85a of the substrate 85 inside the housing 80 by solder or the like, and the tip of the small-diameter portion 12 of the movable pin 10 is in contact with and pressed down on the electrode 86a of the mating device 86. The electrode 85a and electrode 86a are electrically connected via the spring connector 1.

[0020] According to this embodiment, the following effects can be achieved.

[0021] (1) The spring connector 1 has an X-ring 60 as a waterproof elastic body placed around the small-diameter portion 12 of a conductive movable pin 10 protruding from a conductive tube 20, and is housed in a compressed state inside a storage recess 71 of a storage cap 70 fixed to the outer circumference of the tip side of the tube 20. As a result, the X-ring 60 is in watertight contact with the inner circumferential surface of the storage recess 71 and is also in watertight annular contact with the outer circumferential surface 12a of the small-diameter portion 12 at multiple points in the axial direction of the movable pin 10, so the reliability of waterproofing is high and deterioration due to repeated sliding operation of the movable pin 10 is reduced. In addition, since the waterproof elastic body is located on the outside of the tube 20, the reliability of waterproofing is higher compared to when the waterproofing member is placed on the inside of the tube.

[0022] (2) The outer circumference of the tip of the tube 20 is press-fitted into the storage cap 70 that houses the X-ring 60, so no special processing of the tube 20 is required. Since the storage cap 70 is not related to electrical conductivity, there is a great degree of freedom in the selection of material, and it is sufficient if it is a solid that can withstand the compressive reaction force of the X-ring 60.

[0023] (3) The rear end surface of the movable pin 10 is made into an inclined surface 13, and a sphere 30 is interposed between the inclined surface 13 and the coil spring 40. This generates a component force that tilts the movable pin 10 in the direction of the axial direction, and the movable pin 10 can be brought into contact with the inner wall of the tube 20 with the required lateral pressure. In other words, the electrical connection between the movable pin 10 and the tube 20 can be reliably maintained, and a stable conductive path can be formed. Furthermore, by making the sphere 30 conductive, the sphere 30 can also contribute to the electrical connection between the movable pin 10 and the tube 20.

[0024] (4) Since a conductive outer cap 50 that supports the rear end of the coil spring 40 is fixed to the rear end opening of the tube 20, a through structure of conductive material with openings at both ends can be adopted for the tube 20, and the manufacturing of the tube 20 is easy.

[0025] (Embodiment 2) The spring connector 1A according to Embodiment 2 of the present invention will be described using Figures 7 to 9A, 9B and 9C. As shown in these figures, the spring connector 1A uses a waterproof elastic body 60A with a different shape from the X-ring 60 of the spring connector 1 in Embodiment 1. As shown in an enlarged view in Figure 8, the inner circumferential surface of the waterproof elastic body 60A has a pair of annular protrusions 61 and 62 and a recess 63 between them, but unlike the X-ring 60, there are no recesses on the other surfaces, and otherwise it is the same as the X-ring 60. The waterproof elastic body 60A is in contact with the inner circumferential surface 71a of the storage cap 70 by its wide outer circumferential surface 69. Since there is no need for relative movement between the outer circumferential surface 69 of the waterproof elastic body 60A and the inner circumferential surface 71a of the storage cap 70, there is no problem even if the outer circumferential surface 69 is a wide surface without recesses. The other configurations of Embodiment 2 are the same as those of Embodiment 1, and the effects of Embodiment 2 are substantially the same as those of Embodiment 1.

[0026] (Embodiment 3) Figure 10 shows a spring connector 1B according to Embodiment 3 of the present invention, mounted on a housing 90 for electronic equipment or the like. In this case, the housing 90 is used as a housing member to house the X-ring 60, which serves as a waterproof elastic body, on the inside. That is, instead of the housing cap 70 of Embodiment 1, a housing 90 is used which has a housing recess 91 for housing the X-ring 60 inside and a through hole 92 for passing the small diameter portion 12 of the movable pin 10 through. The spring connector 1B is constructed by press-fitting and fixing a tube 20 to the inner circumference of the housing recess 91 where the X-ring 60 is placed. The other configurations are the same as in Embodiment 1.

[0027] Figure 10 shows that the outer cap 50 of the spring connector 1B is connected to the electrode 85a of the substrate 85 inside the housing 90 by solder or the like, and the tip of the movable pin 10 is in contact with and pressed down on the electrode 86a of the mating device 86. The electrodes 85a and 86a are electrically connected via the spring connector 1B. In addition, the X-ring 60, which is stored in a compressed state in the storage recess 91 of the housing 90, prevents liquids such as water from entering the inside of the tube 20. Embodiment 3 has the advantage of reducing the number of parts because the storage cap 70 and gasket 82 shown in Figure 6 are not required, in addition to the advantages of Embodiment 1.

[0028] The embodiments and modifications of the present invention have been described above with reference to the drawings, but these are merely examples of the present invention, and various other configurations can also be adopted.

[0029] The waterproof elastic body arranged around the tip of the movable pin in the present invention only needs to have a structure that makes watertight contact with the inner surface of the storage recess inside the storage member and makes watertight annular contact with the outer surface of the movable pin at multiple locations in the axial direction of the movable pin, and is not limited to the shape of the X-ring 60 in Embodiment 1 or the waterproof elastic body 60A in Embodiment 2.

[0030] In each embodiment, the rear end surface of the movable pin 10 is made into an inclined surface 13, and a coil spring 40 presses the inclined surface 13 via the sphere 30 to generate lateral pressure in a direction that causes the movable pin 10 to contact the inner wall of the tube 20. However, connecting means to ensure electrical conductivity between the movable pin 10 and the tube 20 may be placed inside the tube.

[0031] In Embodiment 1, the outer cap 50 has an air vent hole 52, but the hole 52 may be omitted.

[0032] According to this specification, spring connectors in the following embodiments are provided.

[0033] (Aspect 1) A spring connector comprising: a conductive tube; a conductive movable pin whose tip protrudes from an opening in the tube; a spring disposed inside the tube to bias the movable pin in the axial direction and cause it to protrude; a waterproof elastic body disposed around the tip of the movable pin protruding from the tube; and a housing recess for the waterproof elastic body, wherein at least a portion of the outer circumference of the waterproof elastic body housed in the housing recess contacts the inner surface of the housing recess, and the inner circumference of the waterproof elastic body makes annular contact with the outer surface of the tip of the movable pin at multiple locations in the axial direction of the movable pin.

[0034] According to the above-described embodiment 1, the waterproof elastic body contacts the inner circumferential surface of the storage recess and also makes annular contact with the outer circumferential surface on the tip side of the movable pin at multiple points in the axial direction of the movable pin, thus providing high reliability of waterproofing and minimizing deterioration due to repeated sliding motion of the movable pin.

[0035] (Aspect 2) A spring connector in which the waterproof elastic body is an X-ring.

[0036] According to the above-described embodiment 2, costs can be reduced by using commercially available X-rings.

[0037] (Aspect 3) A storage member having the storage recess and positioned on the outer circumference of the tip side of the tube is provided.

[0038] According to embodiment 3 described above, since the waterproof elastic body housed in the storage member is located on the outside of the tube, the reliability of the waterproofing is higher compared to the case where the waterproof member is placed on the inside of the tube. In addition, the structure of the tube is also simplified.

[0039] (Aspect 4) A spring connector in which the rear end surface of the movable pin is an inclined surface that is inclined with respect to the axial direction of the movable pin.

[0040] According to the above-described embodiment 4, a component force is generated that tilts the movable pin in the axial direction, allowing the movable pin to come into contact with the inner wall of the tube with the required lateral pressure. In other words, the electrical connection between the movable pin and the tube can be reliably maintained, and a stable conductive path can be formed.

[0041] (Aspect 5) A spring connector in which a conductive sphere is interposed between the movable pin and the spring.

[0042] According to the above Aspect 5, by making the sphere conductive, the sphere can also contribute to the electrical connection between the movable pin and the tube.

[0043] (Aspect 6) A spring connector having a conductive cap fixed to the rear end side opening of the tube and supporting the rear end of the spring.

[0044] According to the above Aspect 6, a through structure of a conductive material having openings at both ends can be adopted as the tube, and the manufacture of the tube is easy.

[0045] (Aspect 7) A spring connector in which the reaction force of the spring is greater than the frictional force between the movable pin and the waterproof elastic body.

[0046] According to the above Aspect 7, the movable pin can smoothly return in the protruding direction.

[0047] 1, 1A, 1B Spring connector, 10 Movable pin, 11 Large diameter portion, 12 Small diameter portion, 12a Outer peripheral surface, 13 Inclined surface, 20 Tube, 21 Large diameter surface, 22 Small diameter surface, 30 Sphere, 40 Coil spring, 50 Outer cap, 51 Inner bottom surface, 52 Hole portion, 53 Rear end surface, 60 X-ring (waterproof elastic body), 60A Waterproof elastic body, 61, 62, 66, 67 Annular convex portion, 63, 68 Concave portion, 65 Central hole, 69 Outer peripheral surface, 70 Storage cap, 70A Storage member, 71, 91 Storage concave portion, 71a Inner peripheral surface, 72 Central hole portion, 73 Flange portion, 80, 90 Housing, 85 Substrate, 85a, 86a Electrode, 86 Counterpart device, 92 Through hole portion.

Claims

1. A spring connector comprising: a conductive tube; a conductive movable pin whose tip protrudes from an opening in the tube; a spring disposed inside the tube to bias the movable pin axially and cause it to protrude; a waterproof elastic body disposed around the tip of the movable pin protruding from the tube; and a housing recess for the waterproof elastic body, wherein at least a portion of the outer circumference of the waterproof elastic body housed in the housing recess contacts the inner surface of the housing recess, and the inner circumference of the waterproof elastic body makes annular contact with the outer surface of the tip of the movable pin at multiple locations in the axial direction of the movable pin.

2. The spring connector according to claim 1, wherein the waterproof elastic body is an X-ring.

3. The spring connector according to claim 1 or 2, comprising a storage member having the storage recess and disposed on the outer circumference of the tip side of the tube.

4. The spring connector according to claim 1 or 2, wherein the rear end surface of the movable pin is an inclined surface that is inclined with respect to the axial direction of the movable pin.

5. The spring connector according to claim 1 or 2, wherein a conductive sphere is interposed between the movable pin and the spring.

6. The spring connector according to claim 1 or 2, having a conductive cap fixed to the rear end opening of the tube and supporting the rear end of the spring.

7. The spring connector according to claim 1 or 2, wherein the reaction force of the spring is greater than the frictional force between the movable pin and the waterproof elastic body.

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