Connector

Abstract

This connector comprises a pin and a coil spring for biasing the pin in a prescribed direction. In a state where the pin has been pushed in toward a direction opposite to the prescribed direction, a part of the coil spring enters a region that is at least partially surrounded by another part of the coil spring.

Description

connector

[0001] The present invention relates to a connector.

[0002] In recent years, various connectors have been developed. As described in Patent Document 1, a connector may include a tube, a pin movably attached to the tube, and a coil spring that biases the pin against the tube.

[0003] Japanese Patent Application Laid-Open No. 2021-177446

[0004] The cross-sectional dimensions, such as the wire diameter, of the wire that constitutes a coil spring can increase due to factors such as the plating of the coil spring. Increasing the cross-sectional dimensions of the wire can increase the solid length of the coil spring, the length in which the coils of the coil spring are in contact with each other. The solid length of the coil spring can be reduced by reducing the number of turns of the coil spring. However, reducing the number of turns of the coil spring while maintaining the characteristics of the coil spring, such as stress and load, can reduce the durability of the coil spring.

[0005] One example of an object of the present invention is to reduce the solid length of a coil spring while maintaining the characteristics of the coil spring, without reducing the number of turns of the coil spring. Other objects of the present invention will become apparent from the description of this specification.

[0006] One aspect of the present invention is a connector comprising: a pin; and a coil spring that biases the pin in a predetermined direction, wherein, when the pin is pushed in a direction opposite to the predetermined direction, a portion of the coil spring enters an area at least partially surrounded by another portion of the coil spring.

[0007] According to the above aspect of the present invention, it is possible to reduce the solid length of the coil spring while maintaining the characteristics of the coil spring, without reducing the number of turns of the coil spring.

[0008] FIG. 1 is a cross-sectional view of a connector according to an embodiment. FIG. 2 is a side view of the coil spring shown in FIG. 1. FIG. 3 is a cross-sectional view of a connector according to an embodiment in a state where the pin is pushed toward the tube. FIG. 4 is a side view of the coil spring shown in FIG. 3. FIG. 5 is a side view of the coil spring according to an embodiment in a state where the pin is pushed toward the tube further than the pin shown in FIG. 3. FIG. 6 is a side view of the coil spring shown in FIG. 5. FIG. 7 is a graph for explaining why durability of a coil spring decreases as the number of turns of the coil spring decreases. FIG. 8 is a diagram for explaining the operation of a coil spring according to Modification 1. FIG. 9 is a diagram for explaining the operation of a coil spring according to Modification 1. FIG. 10 is a diagram for explaining the operation of a coil spring according to Modification 1. FIG. 11 is a diagram for explaining the operation of a coil spring according to Modification 2. FIG. 12 is a diagram for explaining the operation of a coil spring according to Modification 2. FIG. 13 is a cross-sectional view of a connector according to Modification 3.

[0009] Hereinafter, embodiments and modifications of the present invention will be described with reference to the drawings. In all the drawings, similar components are designated by similar reference numerals, and descriptions thereof will be omitted as appropriate.

[0010] Fig. 1 is a cross-sectional view of a connector 10 according to an embodiment. Fig. 2 is a side view of a coil spring 300 shown in Fig. 1.

[0011] To explain the directions, the X, Y, and Z directions are defined. In Figures 1 and 2, as well as Figures 3 to 6 and Figures 8 to 14 described below, the X, Y, and Z axes are shown, respectively. The Z direction is parallel to the central axis of the connector 10. The X direction is one of the directions perpendicular to the Z direction. The Y direction is perpendicular to the Z and X directions. In each figure, the Z-axis arrow points from the side where the tube 100 (described later) is located toward the side where the pin 200 (described later) is located. In each figure, the white circle with an X indicating the Y-axis indicates that the Y-axis arrow points toward the back of the paper.

[0012] Hereinafter, unless otherwise specified, the +X side refers to the side indicated by the X-axis arrow, and the -X side refers to the side opposite to the side indicated by the X-axis arrow. Hereinafter, unless otherwise specified, the +Y side refers to the side indicated by the Y-axis arrow, and the -Y side refers to the side opposite to the side indicated by the Y-axis arrow. Hereinafter, unless otherwise specified, the +Z side refers to the side indicated by the Z-axis arrow, and the -Z side refers to the side opposite to the side indicated by the Z-axis arrow. Hereinafter, unless otherwise specified, the XY plane direction refers to the direction perpendicular to the Z direction.

[0013] As shown in Fig. 1, a connector 10 according to the embodiment includes a tube 100, a pin 200, and a coil spring 300. The cross-sectional view of the tube 100 and the pin 200 in Fig. 1 shows a cross-section along a plane perpendicular to the Y direction at the center of the connector 10. The coil spring 300 in Fig. 1 is shown as a side view.

[0014] The tube 100 is formed of a conductor such as a metal. Examples of the metal include copper and copper alloys. Alternatively, the tube 100 may be formed of an insulator and a conductive surface treatment, such as plating, on the insulator. The material of the tube 100 is not limited to these materials as long as it is conductive. As shown in FIG. 1 , the tube 100 includes a tube main body 110 and a lid 120. The tube main body 110 extends in the Z direction. The tube main body 110 defines a hollow space 102 extending in the Z direction. The lid 120 closes one end of the hollow space 102 on the −Z side. The other end of the tube main body 110 on the +Z side includes a locking portion 112 bent toward the center of the tube main body 110 in the XY plane by processing such as crimping. The locking portion 112 opens the other end on the +Z side of the hollow space 102.

[0015] The pin 200 is formed of a conductor such as a metal. Examples of the metal include copper and copper alloys. Alternatively, the pin 200 may be formed of an insulator and a conductive surface treatment, such as plating, on the insulator. The material of the pin 200 is not limited to these materials as long as it is conductive. As shown in FIG. 1 , the pin 200 has a tip portion 210, a small diameter portion 220, and a large diameter portion 230. As shown in FIG. 1 , the diameter of the tip portion 210 in the XY plane decreases toward the +Z side. The end of the tip portion 210 on the +Z side serves as a contact portion that contacts the terminal of the connector 10 to be contacted. The small diameter portion 220 is located on the −Z side relative to the tip portion 210. In the example shown in FIG. 1 , the diameter of the small diameter portion 220 in the XY plane is approximately constant regardless of the position of the small diameter portion 220 in the Z direction. However, the diameter of the small diameter portion 220 in the XY plane may not be substantially constant, and for example, the diameter of the small diameter portion 220 in the XY plane may become smaller toward the tip portion 210. The large diameter portion 230 is located on the -Z side relative to the small diameter portion 220. In the example shown in FIG. 1 , the diameter of the large diameter portion 230 in the XY plane is substantially constant regardless of the position of the large diameter portion 230 in the Z direction. However, the diameter of the large diameter portion 230 in the XY plane may not be substantially constant, and for example, the diameter of the large diameter portion 230 in the XY plane may become larger toward the -Z direction from the small diameter portion 220. The diameter of the large diameter portion 230 in the XY plane is larger than the diameter of the small diameter portion 220 in the XY plane.

[0016] As shown in FIG. 1 , the large diameter portion 230 defines a hollow hole 232 extending in the Z direction. One end of the hollow hole 232 on the −Z side is open at the −Z side end face of the large diameter portion 230. The other end of the hollow hole 232 on the +Z side is closed inside the pin 200. In the example shown in FIG. 1 , the closed inner surface on the +Z side of the hollow hole 232 (the −Z side surface of the tip portion 210) is located approximately at the boundary between the small diameter portion 220 and the tip portion 210. Note that in the example shown in FIG. 1 , the inner surface of the hollow hole 232 is recessed toward the +Z side, but this is not limited thereto. For example, the inner surface of the hollow hole 232 may be shaped to be approximately perpendicular to the Z direction. The position of the inner surface on the +Z side of the hollow hole 232 is not limited to the example shown in FIG. 1 . In the example shown in FIG. 1 , the diameter of the hollow hole 232 in the XY plane is approximately constant regardless of the position of the hollow hole 232 in the Z direction. However, the diameter of the hollow hole 232 in the XY plane direction may be changed depending on the position in the Z direction.

[0017] As shown in FIG. 1 , the pin 200 is movably attached to the tube 100 with the small diameter portion 220 penetrating the +Z side opening of the hollow space 102 in the Z direction and the large diameter portion 230 housed in the hollow space 102. The diameter of the small diameter portion 220 in the XY plane is less than the diameter of the narrowest part of the +Z side opening of the hollow space 102 in the XY plane. Therefore, with the small diameter portion 220 penetrating the +Z side opening of the hollow space 102 in the Z direction, the pin 200 is slidable in the Z direction relative to the tube 100. The diameter of the large diameter portion 230 in the XY plane is larger than the diameter of the narrowest part of the +Z side opening of the hollow space 102 in the XY plane. The large diameter portion 230 includes a step surface 234 located between the outer peripheral surface around the small diameter portion 220 in the Z direction and the outer peripheral surface around the large diameter portion 230 in the Z direction. 1 , pin 200 is biased toward the +Z side by coil spring 300, with the inner circumferential surface of locking portion 112 around the Z direction and step surface 234 of large diameter portion 230 in contact with each other. Even when pin 200 is biased toward the +Z side by coil spring 300, the contact between the inner circumferential surface of locking portion 112 around the Z direction and step surface 234 of large diameter portion 230 prevents pin 200 from coming out of tube 100. Note that "biased toward the +Z direction" in the embodiment corresponds to "biased in a predetermined direction" in the claims.

[0018] In the embodiment, the coil spring 300 is made of a metal wire such as piano wire or stainless steel wire. The coil spring 300 may also be made of a wire other than a metal, such as an insulating material. In the embodiment, the cross section of the wire constituting the coil spring 300 is substantially circular. The cross section of the wire constituting the coil spring 300 may have a shape other than circular. In the embodiment, the surface of the coil spring 300 is at least partially plated with a metal such as nickel. The plating can improve the conductivity of the coil spring 300. Furthermore, the plating can improve the corrosion resistance of the coil spring 300. The surface of the coil spring 300 does not have to be plated.

[0019] 1 and 2, when viewed from the +Z side, the coil spring 300 is wound in a generally spiral shape from a first end 302 located on the −Z side of the coil spring 300 to a second end 304 located on the +Z side of the coil spring 300. In the example shown in FIGS. 1 and 2, when viewed from the Z direction, each winding portion of the coil spring 300 is generally circular. When viewed from the Z direction, each winding portion of an effective winding portion 310 (described later), each winding portion of a first end winding portion 320 (described later), and each winding portion of a second end winding portion 330 (described later) may have a shape other than a circle, such as a generally polygonal shape.

[0020] 1 and 2, the coil spring 300 is housed inside the hollow space 102 and the hollow hole 232 with the first end 302 and the +Z side surface of the lid portion 120 attached to each other and the second end 304 and the +Z side inner surface of the hollow hole 232 attached to each other. In the example shown in Fig. 1, the Z direction dimension of the connector 10 when the pin 200 is not pressed into the tube 100 can be shortened compared to when the hollow hole 232 is not provided in the pin 200.

[0021] 1 and 2, the tip portion 210 is in a free state where it is not pressed toward the -Z side. As shown in FIGS. 1 and 2, when the tip portion 210 is in a free state, the total length in the Z direction of the coil spring 300 is already less than the free length in the Z direction of the coil spring 300 due to a preload caused by Z-directional compression of the +Z side surface of the lid portion 120 and the +Z side inner surface of the hollow hole 232. The free length in the Z direction of the coil spring 300 is the total length in the Z direction of the coil spring 300 when no load is applied to the coil spring 300. By making the total length in the Z direction of the coil spring 300 less than the free length in the Z direction of the coil spring 300 due to the preload, rattle of the coil spring 300 can be suppressed. As shown in FIG. 1, when the tip portion 210 is in a free state, the coil spring 300 biases the pin 200 toward the +Z side relative to the tube 100, with the inner circumferential surface around the Z direction of the locking portion 112 and the stepped surface 234 of the large diameter portion 230 in contact with each other.

[0022] 2, the coil spring 300 has an active winding portion 310, a first end winding portion 320, and a second end winding portion 330. The first end winding portion 320 and the second end winding portion 330 are at least partially located on the −Z side and the +Z side, respectively, of the active winding portion 310.

[0023] As shown in FIGS. 1 and 2 , when the tip portion 210 is in a free state, the overlapping portions of the effective winding portion 310 in the Z direction are spaced apart in the Z direction. When the tip portion 210 is pressed toward the −Z side, the overlapping portions of the effective winding portion 310 in the Z direction move closer to each other in the Z direction, allowing the effective winding portion 310 to act as a spring that urges the pin 200 toward the +Z side. In the example shown in FIG. 2 , the effective winding portion 310 is wound at a substantially equal pitch. The pitch of the effective winding portion 310 may vary depending on the position of the effective winding portion 310. In the example shown in FIG. 2 , the outer diameters of the winding portions of the effective winding portion 310 are substantially equal. The outer diameters of the winding portions of the effective winding portion 310 may be partially different. In the example shown in FIG. 2 , the centers of the winding portions of the effective winding portion 310 in the XY plane overlap each other in the Z direction. The center in the XY plane of some of the winding portions of the effective winding portion 310 may be positioned offset in the XY plane with respect to a virtual line passing in the Z direction through the center in the XY plane of other parts of the winding portion of the effective winding portion 310.

[0024] As shown in FIGS. 1 and 2 , when the tip end portion 210 is in a free state, the first end winding portion 320 is wound one turn from the first end 302 as viewed from the +Z side. In the example shown in FIG. 2 , the first end 302 is located on the −X side of the center of the first end winding portion 320 in the XY plane. The position of the first end 302 is not limited to the example shown in FIG. 2 . The diameter of the first end winding portion 320 in the XY plane is larger than the diameter of the first endmost effective winding portion 312, which is located on the −Z side of the effective winding portion 310. As shown in FIG. 2 , when the tip end portion 210 is in a free state, the overlapping portions of the first end winding portion 320 and the first endmost effective winding portion 312 in the Z direction are at least partially in contact with each other. In the example shown in FIG. 2 , the first end 302 and a first boundary portion 306, which is offset by approximately one turn from the first end 302 of the coil spring 300, are in contact with each other. In the example shown in Fig. 2, the first boundary portion 306 is a portion that functions as both the first end winding portion 320 and the active winding portion 310 of the coil spring 300. The position of the first boundary portion 306 is not limited to the example shown in Fig. 2. As shown in Figs. 1 and 2, when the tip portion 210 is in a free state, the first end winding portion 320 does not act as a spring due to at least partial contact between the portions of the first end winding portion 320 and the first endmost active winding portion 312 that overlap in the Z direction, including the contact between the first end portion 302 and the first boundary portion 306.

[0025] The first end winding portion 320 may include more than one turn, such as 1.5 turns, 2 turns, 2.5 turns, or 3 turns. When the first end winding portion 320 includes more than one turn, the portions of the first end winding portion 320 that overlap in the Z direction are in at least partial contact with each other. Even when the first end winding portion 320 includes more than one turn, when the tip portion 210 is in a free state, the first end winding portion 320 does not act as a spring due to the at least partial contact between the portions of the first end winding portion 320 and the first endmost effective winding portion 312 that overlap in the Z direction, as in the example shown in FIG. 2 .

[0026] As shown in FIGS. 1 and 2 , when the tip end portion 210 is in a free state, the second end winding portion 330 is wound one turn from the second end 304 when viewed from the +Z side. In the example shown in FIG. 2 , the second end 304 is located on the −X side of the center of the second end winding portion 330 in the XY plane. The position of the second end 304 is not limited to the example shown in FIG. 2 . The diameter of the second end winding portion 330 in the XY plane is approximately equal to the diameter of the second endmost effective winding portion 314, which is located on the +Z side of the effective winding portion 310. Note that to prevent burrs on the cut surface of the wire at the second end 304 from damaging outer components around the coil spring 300 in the Z direction, the second end 304 may be located slightly closer to the center of the second end winding portion 330 in the XY plane than the second boundary portion 308. As shown in FIG. 2 , when the distal end portion 210 is in a free state, the overlapping portions of the second end winding portion 330 and the second endmost effective winding portion 314 in the Z direction are in at least partial contact with each other. In the example shown in FIG. 2 , the second end 304 and a second boundary portion 308, which is offset by approximately one turn from the second end 304 of the coil spring 300, are in contact with each other. In the example shown in FIG. 2 , the second boundary portion 308 is a portion that functions as both the second end winding portion 330 and the effective winding portion 310 of the coil spring 300. The position of the second boundary portion 308 is not limited to the example shown in FIG. 2 . As shown in FIGS. 1 and 2 , when the distal end portion 210 is in a free state, the second end winding portion 330 does not function as a spring due to at least partial contact between the overlapping portions of the second end winding portion 330 and the second endmost effective winding portion 314 in the Z direction, including the contact between the second end 304 and the second boundary portion 308.

[0027] The second end turn portion 330 may include more than one turn, similar to the first end turn portion 320.

[0028] Figure 3 is a cross-sectional view of the connector 10 according to the embodiment in a state where the pin 200 is pushed toward the tube 100. Figure 4 is a side view of the coil spring 300 shown in Figure 3. Figure 5 is a side view of the coil spring 300 according to the embodiment in a state where the pin 200 is pushed further toward the tube 100 than the pin 200 shown in Figure 3. Figure 6 is a side view of the coil spring 300 shown in Figure 5.

[0029] The operation of the connector 10 according to the embodiment will be described with reference to FIGS.

[0030] As shown in FIGS. 1 and 2 , when the tip portion 210 is in a free state, the first end winding portion 320 and the first endmost effective winding portion 312 at least partially overlap in the Z direction, with the first end winding portion 320 positioned at least partially offset from the first endmost effective winding portion 312 outside the area surrounded by the coil spring 300 in the Z direction. Therefore, when the first end winding portion 320 and the first endmost effective winding portion 312 are projected onto the same plane perpendicular to the Z direction, they partially overlap and are partially offset in the XY plane. In one example, the X-direction dimension of the portion of the first end 302 that overlaps with the first boundary portion 306 in the Z direction is between ¼ and ½ times the wire diameter of the wire constituting the coil spring 300. In one example, the X-direction dimension of the portion of the first boundary portion 306 that overlaps with the first end 302 in the Z direction is between ¼ and ½ times the wire diameter of the wire constituting the coil spring 300.

[0031] 1 and 2 , when the tip portion 210 is in a free state, substantially the entire second end winding portion 330 and substantially the entire second endmost effective winding portion 314 overlap each other in the Z direction. Therefore, the projections of the second end winding portion 330 and the second endmost effective winding portion 314 onto the same plane perpendicular to the Z direction overlap each other without any misalignment in the XY plane. For example, in the example shown in FIG. 2 , the X-direction center of the second end portion 304 and the X-direction center of the second boundary portion 308 overlap each other in the Z direction. However, the projections of the X-direction center of the second end portion 304 and the X-direction center of the second boundary portion 308 onto the same plane perpendicular to the Z direction may be slightly misaligned in the X direction.

[0032] 3 and 4, the pin 200 is pushed toward the tube 100, thereby bringing the bottom surface on the +Z side of the hollow hole 232 closer to the +Z side surface of the lid portion 120. The distance in the Z direction between the +Z side surface of the lid portion 120 and the +Z side bottom surface of the hollow hole 232 is shortened, thereby compressing the coil spring 300 in the Z direction. As shown in FIGS. 3 and 4, the coil spring 300 is compressed in the Z direction until the overlapping portions of the effective windings 310 in the Z direction come into contact with each other.

[0033] As shown in Fig. 3, the +Z side end of tip portion 210 is located on the +Z side of a position that is approximately flush with the +Z side end of the outer peripheral surface around locking portion 112 in the Z direction. Therefore, in the example shown in Fig. 3, pin 200 is not completely pushed into tube 100. To further ensure the stroke length of connector 10, pin 200 needs to be pushed further toward tube 100 than pin 200 shown in Fig. 3. The stroke length of connector 10 is the distance that pin 200 can move in the Z direction when pin 200 is attached to tube 100.

[0034] 5 and 6, by further pushing the pin 200 toward the tube 100, the bottom surface on the +Z side of the hollow hole 232 is brought even closer to the +Z side surface of the lid portion 120. As the distance in the Z direction between the +Z side surface of the lid portion 120 and the +Z side bottom surface of the hollow hole 232 becomes even shorter, the coil spring 300 is further compressed in the Z direction.

[0035] As shown in FIGS. 3 and 4 , before the pin 200 is further pushed toward the tube 100, the first end winding portion 320 and the first endmost effective winding portion 312 at least partially overlap in the Z direction, and the first end winding portion 320 is positioned at least partially outside the area surrounded by the coil spring 300 in the Z direction relative to the first endmost effective winding portion 312. Therefore, as shown in FIGS. 5 and 6 , as the pin 200 is further pushed toward the tube 100, at least a portion of the first endmost effective winding portion 312 can slide relative to the first end winding portion 320 and enter the area at least partially surrounded by the first end winding portion 320 in the Z direction. In the example shown in FIGS. 5 and 6 , the first end winding portion 320 and the first endmost effective winding portion 312 are at least partially located on approximately the same plane. For example, in the example shown in FIG. 6 , the Z-direction center of the first end portion 302 and the Z-direction center of the first boundary portion 306 are aligned in the X direction. Therefore, the overall length in the Z direction of the coil spring 300 shown in Figures 5 and 6 can be shorter than the overall length in the Z direction of the coil spring 300 shown in Figures 3 and 4 by the length of the first endmost effective winding portion 312.

[0036] 3 and 4, before the pin 200 is further pushed toward the tube 100, substantially the entire second end winding portion 330 and substantially the entire second endmost effective winding portion 314 overlap each other in the Z direction. Therefore, even if the pin 200 is further pushed toward the tube 100, as shown in Figures 5 and 6, one of the second end winding portion 330 and the second endmost effective winding portion 314 does not slide relative to the other of the second end winding portion 330 and the second endmost effective winding portion 314, and substantially the entire second end winding portion 330 and substantially the entire second endmost effective winding portion 314 remain overlapping each other in the Z direction.

[0037] As shown in Fig. 5, the +Z side end of tip portion 210 and the +Z side end of the outer circumferential surface around locking portion 112 in the Z direction are positioned on approximately the same plane. Therefore, in the example shown in Fig. 5, pin 200 is fully pushed into tube 100. Therefore, in the operation of connector 10 described with reference to Figs. 1 to 6, a sufficient stroke length of connector 10 can be ensured.

[0038] In the embodiment, at least a portion of the first endmost effective winding portion 312 enters into the region at least partially surrounded by the first end winding portion 320 in the Z direction, thereby reducing the solid length of the coil spring 300 in the Z direction when the windings of the coil spring 300 are in contact with each other. Therefore, in the embodiment, compared to a case where no portion of the coil spring 300 enters into the region surrounded by any other portion of the coil spring 300 in the Z direction, the solid length of the coil spring 300 in the Z direction can be reduced while maintaining the characteristics of the coil spring 300 and without reducing the number of turns of the coil spring 300.

[0039] In the embodiment, at least a portion of the first endmost active winding portion 312 enters the area at least partially surrounded in the Z direction by the first end winding portion 320, so that a portion of the coil spring 300 enters the area at least partially surrounded in the Z direction by another portion of the coil spring 300. By having a portion of the coil spring 300 enter the area at least partially surrounded in the Z direction by another portion of the coil spring 300, it is possible to reduce the solid length of the coil spring 300 in the Z direction while maintaining the characteristics of the coil spring 300, without reducing the number of turns of the coil spring 300. However, the method of having a portion of the coil spring 300 enter the area at least partially surrounded in the Z direction by another portion of the coil spring 300 is not limited to the method described in the embodiment.

[0040] In another example, when the tip portion 210 is in a free state, the first end winding portion 320 and the first endmost effective winding portion 312 may at least partially overlap in the Z direction, and the first endmost effective winding portion 312 may be positioned at least partially outside the area surrounded by the coil spring 300 in the Z direction relative to the first end winding portion 320. In this other example, when the pin 200 is pushed toward the tube 100, at least a portion of the first end winding portion 320 slides relative to the first endmost effective winding portion 312 and enters the area at least partially surrounded by the first endmost effective winding portion 312 in the Z direction. Therefore, compared to a case where no portion of the coil spring 300 enters the area at least partially surrounded by other portions of the coil spring 300 in the Z direction, it is possible to reduce the solid length of the coil spring 300 in the Z direction while maintaining the characteristics of the coil spring 300 without reducing the number of turns of the coil spring 300.

[0041] In another example, when the distal end portion 210 is in a free state, the projections of the first end winding portion 320 and the first endmost effective winding portion 312 onto the same plane perpendicular to the Z direction may be shifted from each other in the XY plane direction without overlapping even partially. For example, when the distal end portion 210 is in a free state, the entire projection of the first endmost effective winding portion 312 may be located in an area surrounded in the Z direction by the projection of the first end winding portion 320. Alternatively, when the distal end portion 210 is in a free state, the entire projection of the first end winding portion 320 may be located in an area surrounded in the Z direction by the projection of the first endmost effective winding portion 312.

[0042] In another example, when the tip portion 210 is in a free state, the overlapping portions of the first end winding portion 320 and the first endmost effective winding portion 312 in the Z direction do not have to be in contact with each other. For example, when the tip portion 210 is in a free state, a gap may exist between the first end 302 and the first boundary portion 306. Even if a gap exists between the overlapping portions of the first end winding portion 320 and the first endmost effective winding portion 312 in the Z direction, the pin 200 can be pushed toward the tube 100 to bring the overlapping portions of the first end winding portion 320 and the first endmost effective winding portion 312 in the Z direction into contact with each other.

[0043] In other examples, the timing at which the first endmost effective winding portion 312 slides relative to the first end winding portion 320 may be different from the timing according to the embodiment. For example, depending on how the coil spring 300 is wound, the first endmost effective winding portion 312 can slide relative to the first end winding portion 320 at the same time that overlapping portions of the coil spring 300 in the Z direction come into contact with each other.

[0044] In another example, as the pin 200 is pressed toward the tube 100, more than one turn of the coil spring 300 may enter an area surrounded in the Z direction by more than one other turn of the coil spring 300. For example, in the embodiment, as the pin 200 is pressed toward the tube 100, one turn of the first endmost effective winding portion 312 enters an area surrounded in the Z direction by one turn of the first end winding portion 320. However, as the pin 200 is pressed toward the tube 100, more than one turn of the first endmost effective winding portion 312 may enter an area surrounded in the Z direction by more than one turn of the first end winding portion 320.

[0045] In another example, when the tip portion 210 is in a free state, the first end winding portion 320 may have three or more windings with different outer diameters in the XY plane. For example, if the first end winding portion 320 includes three or more windings whose outer diameters in the XY plane decrease toward the +Z side, pushing the pin 200 toward the tube 100 can cause a chain reaction in which each winding portion of the first end winding portion 320 enters a region at least partially surrounded in the Z direction by windings located on the −Z side of the first end winding portion 320.

[0046] Fig. 7 is a graph for explaining why a decrease in the number of turns of the coil spring 300 reduces the durability of the coil spring 300. In the graph shown in Fig. 7, the horizontal axis represents the amount of pressing D (unit: mm) of the pin 200 into the tube 100, and the vertical axis represents the load F (unit: N) of the coil spring 300.

[0047] A reduction in the number of turns of the coil spring 300 may reduce the durability of the coil spring 300 in the following ways.

[0048] As shown by the first line L1 in FIG. 7 , the coil spring 300 is designed so that the load F of the coil spring 300 becomes a predetermined load F1 when the amount of pressing D of the pin 200 into the tube 100 becomes a predetermined amount D1. The first line L1 shows the relationship between the load F and the amount of pressing D when the number of turns of the coil spring 300 and the tight winding length are not reduced. In this embodiment, the load F1 that corresponds to the amount of pressing D1 is defined as the characteristic of the coil spring 300. As shown by the first line L1, the second line L2, and the third line L3 in FIG. 7 , the load F of the coil spring 300 is linearly proportional to the amount of pressing D of the pin 200 into the tube 100, with the spring constant of the coil spring 300 serving as the proportionality coefficient. The origin of the graph shown in FIG. 7 is the intersection of the horizontal axis representing the amount of pressing D and the vertical axis representing the load F. In the graph shown in Fig. 7, the load F at the intersection of the vertical axis indicating the load F with the first line L1, the second line L2, and the third line L3 indicates the preload of the coil spring 300. In the graph shown in Fig. 7, the coil spring 300 is not compressed in the Z direction at the intersection of the horizontal axis indicating the amount of compression D with the first line L1, the second line L2, and the third line L3. In the graph shown in Fig. 7, the longer the distance from the origin of the graph to the intersection of the horizontal axis indicating the amount of compression D with the first line L1, the second line L2, and the third line L3, the longer the free length of the coil spring 300 in the Z direction.

[0049] The cross-sectional dimensions, such as the wire diameter, of the wire constituting the coil spring 300 may increase due to factors such as the plating of the coil spring 300. Increasing the cross-sectional dimensions of the wire constituting the coil spring 300 may increase the Z-direction contact length of the coil spring 300 when the windings of the coil spring 300 are in contact with each other. Reducing the number of turns of the coil spring 300 may shorten the Z-direction contact length of the coil spring 300. However, reducing the number of turns of the coil spring 300 increases the spring constant of the coil spring 300. Therefore, even if the coil spring 300 is designed according to the relationship between the load F and the amount of compression D shown in the first line L1 in FIG. 7 , reducing the number of turns of the coil spring 300 causes the coil spring 300 to operate according to the relationship between the load F and the amount of compression D shown in the second line L2 in FIG. 7 . As shown in FIG. 7 , due to the increase in the spring constant of the coil spring 300, the slope of the second line L2 is greater than the slope of the first line L1.

[0050] 7, when the coil spring 300 operates according to the relationship between the load F and the displacement D indicated by the second line L2, the load F of the coil spring 300 increases and the torsional stress of the coil spring 300 increases in a range where the displacement D is greater than D1, compared to when the coil spring 300 operates according to the relationship between the load F and the displacement D indicated by the first line L1. The increase in the torsional stress of the coil spring 300 may reduce the durability of the coil spring 300. As can be seen from the fact that the distance from the origin of the graph to the intersection of the horizontal axis representing the displacement D and the second line L2 is less than the distance from the origin of the graph to the intersection of the horizontal axis representing the displacement D and the first line L1, an increase in the spring constant of the coil spring 300 reduces the free length of the coil spring 300 in the Z direction.

[0051] To ensure the preload of the coil spring 300, the number of turns of the coil spring 300 may be set equal to the number of turns of the coil spring 300 according to the relationship between the load F and the displacement D shown in the second line L2 in Figure 7 , and the relationship between the load F and the displacement D shown in the third line L3 in Figure 7 may be set to compensate for the free length of the coil spring 300 in the Z direction. As shown in Figure 7, the distance from the origin of the graph to the intersection of the horizontal axis representing the displacement D and the first line L1 is equal to the distance from the origin of the graph to the intersection of the horizontal axis representing the displacement D and the third line L3. However, as shown in Figure 7, when the coil spring 300 operates according to the relationship between the load F and the displacement D shown in the third line L3, the load F is greater than the load F when the coil spring 300 operates according to the relationship between the load F and the displacement D shown in the first line L1 in Figure 7, at all displacements D, including the displacement D1. Therefore, when the coil spring 300 operates in accordance with the relationship between the load F and the amount of compression D shown by the third line L3, the torsional stress of the coil spring 300 increases, and the durability of the coil spring 300 decreases, compared to when the coil spring 300 operates in accordance with the relationship between the load F and the amount of compression D shown by the first line L1. Furthermore, as shown in Figure 7, the load F2 at the amount of compression D1 on the third line L3 is larger than the load F1 originally targeted at the amount of compression D1 on the first line L1.

[0052] As explained using FIG. 7 , by reducing the number of turns of the coil spring 300, the Z-direction contact length of the coil spring 300 can be reduced while maintaining the characteristics of the coil spring 300. However, reducing the number of turns of the coil spring 300 may reduce the durability of the coil spring 300. Furthermore, if the number of turns of the coil spring 300 is reduced to achieve a predetermined compression amount (compression amount D1 in the embodiment) in order to maintain the characteristics of the coil spring 300 in the embodiment, it is necessary to increase the free length of the coil spring 300. In this case, the load at the predetermined compression amount becomes larger than the load (load F1 in the embodiment) initially targeted at the predetermined compression amount before the number of turns of the coil spring 300 was reduced. In contrast, in the embodiment, the Z-direction contact length of the coil spring 300 can be reduced while maintaining the characteristics of the coil spring 300 without reducing the number of turns of the coil spring 300. In other words, because the number of turns of the coil spring 300 is not reduced, it is possible to maintain the characteristics of the coil spring 300 at the load F1 that corresponds to the compression amount D1 shown in the first straight line L1 in Fig. 7, while reducing the contact length without reducing the durability of the coil spring 300. Therefore, in this embodiment, the durability of the coil spring 300 can be improved compared to when the number of turns of the coil spring 300 is reduced.

[0053] 8 to 10 are diagrams illustrating the operation of the coil spring 300A according to Modification 1. Figures 8, 9, and 10 of Modification 1 correspond to Figures 2, 4, and 6 of the embodiment. The coil spring 300A according to Modification 1 shown in Figures 8 to 10 is similar to the coil spring 300 according to the embodiment shown in Figures 1 to 6, except for the following points. The coil spring 300A according to Modification 1 shown in Figures 8 to 10 biases the pin 200 against the tube 100 in the same way as the coil spring 300 according to the embodiment shown in Figures 1 to 6.

[0054] As shown in FIG. 8, when the tip portion 210 is in a free state, the first end winding portion 320A and the first endmost effective winding portion 312A are at least partially overlapping in the Z direction, and the first end winding portion 320A is positioned at least partially outside the area surrounded by the coil spring 300A in the Z direction relative to the first endmost effective winding portion 312A.

[0055] As shown in FIG. 8, when the tip portion 210 is in a free state, the second end winding portion 330A and the second endmost effective winding portion 314A are at least partially overlapping in the Z direction, and the second end winding portion 330A is positioned at least partially outside the area surrounded by the coil spring 300A in the Z direction relative to the second endmost effective winding portion 314A.

[0056] Next, as shown in FIG. 9, by pushing the pin 200 toward the tube 100, the coil spring 300A is compressed in the Z direction until the overlapping portions of the effective windings 310A in the Z direction come into contact with each other.

[0057] Next, as shown in FIG. 10 , by further pushing the pin 200 toward the tube 100, the coil spring 300A is further compressed in the Z direction. As shown in FIG. 10 , due to the compression of the coil spring 300A in the Z direction, at least a portion of the first endmost effective winding portion 312A slides relative to the first end winding portion 320A and enters into the area at least partially surrounded by the first end winding portion 320A in the Z direction. In the example shown in FIG. 10 , the first end winding portion 320A and the first endmost effective winding portion 312A are at least partially located on approximately the same plane. As shown in FIG. 10 , due to the compression of the coil spring 300A in the Z direction, at least a portion of the second endmost effective winding portion 314A slides relative to the second end winding portion 330A and enters into the area at least partially surrounded by the second end winding portion 330A in the Z direction. In the example shown in Fig. 10, the second end winding portion 330A and the second endmost effective winding portion 314A are at least partially located on the same plane, so the overall length in the Z direction of the coil spring 300A shown in Fig. 10 can be shorter than the overall length in the Z direction of the coil spring 300A shown in Fig. 9 by the length of the first endmost effective winding portion 312A and the second endmost effective winding portion 314A.

[0058] 8 to 10 , compared to when no portion of the coil spring 300A enters the region at least partially surrounded by other portions of the coil spring 300A in the Z direction, the solid length of the coil spring 300A in the Z direction can be reduced without reducing the number of turns of the coil spring 300A while maintaining the characteristics of the coil spring 300A (similar to the characteristics of the coil spring 300 in the above-described embodiment). The method for having a portion of the coil spring 300A enter the region at least partially surrounded by other portions of the coil spring 300A in the Z direction is not limited to the method according to Modification 1. The method for having a portion of the coil spring 300A enter the region at least partially surrounded by other portions of the coil spring 300A in the Z direction may be the same as the methods described in the other examples of the embodiment.

[0059] 11 to 13 are diagrams illustrating the operation of a coil spring 300B according to Modification 2. FIGS. 11, 12, and 13 of Modification 2 correspond to FIGS. 2, 4, and 6 of the embodiment, respectively. The coil spring 300B according to Modification 2 shown in FIGS. 11 to 13 is similar to the coil spring 300 according to the embodiment shown in FIGS. 1 to 6, except for the following points. The coil spring 300B according to Modification 2 shown in FIGS. 11 to 13 biases the pin 200 against the tube 100 in the same way as the coil spring 300 according to the embodiment shown in FIGS. 1 to 6.

[0060] As shown in Figures 11 to 13, the coil spring 300B according to the second modification has a first effective winding portion 310B1, a second effective winding portion 310B2, a first end winding portion 320B, a second end winding portion 330B, and a third end winding portion 340B.

[0061] The cross-sectional views of the coil spring 300B in Figures 11 to 13 show a cross section along a plane perpendicular to the Y direction at the center of the coil spring 300B. In Figures 11 to 13, hatching inclined toward the -X side and the +Z side in the first effective winding portion 310B1 and the second effective winding portion 310B2 indicates the cross section of the portion that functions as the first effective winding portion 310B1 and the second effective winding portion 310B2 of the coil spring 300B, respectively. In Figures 11 to 13, hatching inclined toward the +X side and the +Z side in the first end winding portion 320B, the second end winding portion 330B, and the third end winding portion 340B indicates the cross section of the portion that functions as the first end winding portion 320B, the second end winding portion 330B, and the third end winding portion 340B of the coil spring 300B, respectively. 11 to 13, cross-hatching in the first effective winding portion 310B1 and the first end winding portion 320B, where hatching inclined toward the -X side and the +Z side intersects with hatching inclined toward the +X side and the +Z side, indicates a cross section of a portion that functions as both the first effective winding portion 310B1 and the first end winding portion 320B of the coil spring 300B. In FIGS. 11 to 13, cross-hatching in the first effective winding portion 310B1 and the third end winding portion 340B indicates a cross section of a portion that functions as both the first effective winding portion 310B1 and the third end winding portion 340B of the coil spring 300B. In FIGS. 11 to 13, cross-hatching in the second effective winding portion 310B2 and the second end winding portion 330B indicates a cross section of a portion that functions as both the second effective winding portion 310B2 and the second end winding portion 330B of the coil spring 300B. 11 to 13, the cross-hatching in the second effective winding portion 310B2 and the third end winding portion 340B indicates the cross section of the portion that functions as both the second effective winding portion 310B2 and the third end winding portion 340B of the coil spring 300B.

[0062] As shown in FIG. 11, when the tip portion 210 is in a free state, the first seat winding portion 320B is at least partially located on the −Z side relative to the first effective winding portion 310B1, the second seat winding portion 330B is at least partially located on the +Z side relative to the second effective winding portion 310B2, and the third seat winding portion 340B is at least partially located between the first effective winding portion 310B1 and the second effective winding portion 310B2 in the Z direction.

[0063] 11, when the tip portion 210 is in a free state, the overlapping portions of the first effective winding portion 310B1 and the second effective winding portion 310B2 in the Z direction are spaced apart from each other in the Z direction. Therefore, when the tip portion 210 is pressed toward the −Z side, each of the first effective winding portion 310B1 and the second effective winding portion 310B2 can act as a spring.

[0064] 11, when the tip end portion 210 is in a free state, the overlapping portions of the first end winding portion 320B, the second end winding portion 330B, and the third end winding portion 340B in the Z direction are in at least partial contact with each other, and therefore, each of the first end winding portion 320B, the second end winding portion 330B, and the third end winding portion 340B does not act as a spring.

[0065] Hereinafter, unless otherwise specified, the term "endmost effective winding portion 312B" according to Modification 2 refers to the winding portion of the first effective winding portion 310B1 that is closest to the +Z side. Hereinafter, unless otherwise specified, the term "third boundary portion 307B" according to Modification 2 refers to the boundary portion between the first effective winding portion 310B1 and the third end winding portion 340B. Hereinafter, unless otherwise specified, the term "fourth boundary portion 309B" according to Modification 2 refers to the boundary portion between the second effective winding portion 310B2 and the third end winding portion 340B.

[0066] 11 , when the tip portion 210 is in a free state, the third end winding portion 340B and the endmost effective winding portion 312B at least partially overlap in the Z direction, and the third end winding portion 340B is positioned at least partially outside the area surrounded by the coil spring 300B in the Z direction relative to the endmost effective winding portion 312B. For example, in the example shown in FIG. 11 , the fourth boundary portion 309B is positioned farther from the center of the coil spring 300B in the X direction than the third boundary portion 307B.

[0067] Next, as shown in FIG. 12, by pushing the pin 200 toward the tube 100, the coil spring 300B is compressed in the Z direction until the overlapping portions of the first effective winding portion 310B1 and the second effective winding portion 310B2 in the Z direction come into contact with each other.

[0068] Next, as shown in FIG. 13 , by further pushing the pin 200 toward the tube 100, the coil spring 300B is further compressed in the Z direction. As shown in FIG. 13 , due to the compression of the coil spring 300B in the Z direction, at least a portion of the endmost effective winding portion 312B slides relative to the third end winding portion 340B and enters the area at least partially surrounded by the third end winding portion 340B in the Z direction. In the example shown in FIG. 13 , the −X side portion of the endmost effective winding portion 312B, including the third boundary portion 307B, enters the area at least partially surrounded by the third end winding portion 340B in the Z direction. The +X side portion of the endmost effective winding portion 312B may also enter the area at least partially surrounded by the third end winding portion 340B in the Z direction. In the example shown in Fig. 13, fourth boundary 309B and a portion of endmost effective winding 312B that is shifted from third boundary 307B toward the -Z side by approximately one turn of winding are in contact with each other. Therefore, the overall length in the Z direction of coil spring 300B shown in Fig. 13 can be made shorter than the overall length in the Z direction of coil spring 300B shown in Fig. 12.

[0069] 11 to 13 , compared to when no portion of the coil spring 300B enters the area at least partially surrounded by other portions of the coil spring 300B in the Z direction, the solid length of the coil spring 300B can be reduced in the Z direction while maintaining the characteristics of the coil spring 300B (similar to the characteristics of the coil spring 300 in the above-described embodiment) without reducing the number of turns of the coil spring 300B. The method for having a portion of the coil spring 300B enter the area at least partially surrounded by other portions of the coil spring 300B in the Z direction is not limited to the method according to Modification 2. The method for having a portion of the coil spring 300B enter the area at least partially surrounded by other portions of the coil spring 300B in the Z direction may be the same as the methods described in the other examples of the embodiment.

[0070] 1 to 6 and 8 to 13, depending on the position of the end turn portion of the coil spring, a portion of the coil spring can be made to extend into an area at least partially surrounded by another portion of the coil spring in the Z direction at least at one desired location of the coil spring. For example, if the coil spring has multiple end turn portions, a portion of the coil spring can be made to extend into an area at least partially surrounded by another portion of the coil spring in the Z direction at all of the multiple end turn portions when the pin 200 is pressed toward the tube 100.

[0071] 14 is a cross-sectional view of a connector 10C according to Modification 3. The connector 10C according to Modification 3 is similar to the connector 10 according to the embodiment, except for the following points.

[0072] The connector 10C according to the third modification includes a pin 200C. The pin 200C according to the third modification has a tip portion 210C, a small diameter portion 220C, and a large diameter portion 230C, similar to the pin 200 according to the embodiment. The tip portion 210C, the small diameter portion 220C, and the large diameter portion 230C according to the third modification correspond to the tip portion 210, the small diameter portion 220, and the large diameter portion 230 according to the embodiment, respectively. The large diameter portion 230C according to the third modification includes a step surface 234C, similar to the large diameter portion 230 according to the embodiment.

[0073] The pin 200C according to the third modification does not define a hole corresponding to the hollow hole 232 according to the embodiment. Therefore, the second end 304 of the coil spring 300 is attached to the -Z side surface of the large diameter portion 230C. The coil spring 300 of the connector 10C according to the third modification can operate in the same manner as the coil spring 300 of the connector 10 according to the embodiment, even if it does not have a hole corresponding to the hollow hole 232 according to the embodiment. Therefore, in the connector 10C according to the third modification, the solid length of the coil spring 300 in the Z direction can be reduced while maintaining the characteristics of the coil spring 300, without reducing the number of turns of the coil spring 300, compared to when no part of the coil spring 300 enters an area at least partially surrounded by other parts of the coil spring 300 in the Z direction.

[0074] The connector 10C according to the third modification uses the coil spring 300 according to the embodiment. However, the connector 10C according to the third modification may use the coil spring 300 described in the other examples of the embodiment. Alternatively, the connector 10C according to the third modification may use the coil spring 300A according to the first modification or the coil spring 300B according to the second modification.

[0075] Although the embodiments and modifications of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0076] According to the present specification, the following aspects of the connector are provided: (Aspect 1) In Aspect 1, the connector includes a pin and a coil spring that biases the pin in a predetermined direction, and when the pin is pushed in a direction opposite to the predetermined direction, a portion of the coil spring enters a region at least partially surrounded by another portion of the coil spring.

[0077] According to the above-described aspect, the solid length of the coil spring can be reduced while maintaining the characteristics of the coil spring without reducing the number of turns of the coil spring, compared to when no part of the coil spring enters an area at least partially surrounded by other parts of the coil spring.

[0078] (Aspect 2) In aspect 2, the other portion of the coil spring is positioned at least partially shifted outside the area surrounded by the coil spring relative to the first portion of the coil spring.

[0079] According to the above-described aspect, when the pin is pushed toward the tube, a portion of the coil spring can enter a region at least partially surrounded by another portion of the coil spring.

[0080] This application claims priority based on Japanese Patent Application No. 2024-027547, filed February 27, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0081] 10, 10C Connector, 100 Tube, 102 Hollow space, 110 Tube body, 112 Locking portion, 120 Lid portion, 200, 200C Pin, 210, 210C Tip portion, 220, 220C Small diameter portion, 230, 230C Large diameter portion, 232 Hollow hole, 234, 234C Step surface, 300, 300A, 300B Coil spring, 302 First end portion, 304 Second end portion, 306 First boundary portion, 307B Third boundary portion, 308 Second boundary portion, 309B Fourth boundary portion, 310, 310A Effective winding portion, 310B1 First effective winding portion, 310B2 Second effective winding portion, 312, 312A First endmost effective winding portion, 312B Endmost effective winding portion, 314, 314A; second endmost effective winding portion, 320, 320A, 320B; first end winding portion, 330, 330A, 330B; second end winding portion, 340B; third end winding portion, L1: first straight line; L2: second straight line; L3: third straight line

Claims

1. A connector comprising: a pin; and a coil spring that biases the pin in a predetermined direction, wherein, when the pin is pushed in a direction opposite to the predetermined direction, a portion of the coil spring enters an area at least partially surrounded by another portion of the coil spring.

2. The connector according to claim 1, wherein the other portion of the coil spring is positioned at least partially outside the area surrounded by the coil spring relative to the first portion of the coil spring.

Images