JP4175214B2 - Fastening method for securing continuity, washer and auxiliary washer - Google Patents

Description

  The present invention relates to a fastening method for securing conduction with a circuit pattern provided on a fastened object, and a washer and an auxiliary washer used at the time of fastening.

  A configuration as shown in FIG. 10 is known for ensuring electrical connection between a circuit pattern on a substrate to be fastened and a housing. A substrate 103 provided with a copper foil 102 as a circuit pattern is placed on the housing 101, and a screw 105 with a flat washer 104 is tightened in a hole provided on the substrate. At this time, the plain washer 104 comes into contact with the copper foil 102 to ensure conduction between the copper foil 102 on the substrate 103 and the housing 101.

  However, a coating agent that is an insulator is usually applied on the copper foil 102, and the insulator is interposed between the copper foil 102 and the copper foil 102 and the plain washer 104 cannot be electrically connected. In order to avoid this, it is possible to apply the coating agent by masking the copper foil 102 where the flat washer 104 contacts, or apply the coating agent while avoiding the copper foil 102 where the flat washer 104 contacts. Though possible, productivity is poor.

  Here, what is shown in Patent Document 1 is disclosed. In the invention of Patent Document 1, the insulator is broken by using a burr-like protrusion formed when the washer is pressed to ensure conduction.

  Patent Document 2 is disclosed as a washer provided with a protrusion. In Patent Document 2, teeth are provided on the washer and meshed with both the shield case and the terminal fitting to ensure conduction.

Moreover, although it is not a washer, patent document 3 discloses a rivet provided with a ridge, and discloses breaking a coating film on a metal plate to ensure conduction.
Japanese Utility Model Publication No.2-113010 JP-A-9-23397 JP 2001-27212 A

  However, in the invention of Patent Document 1, a burr-like protrusion alone is insufficient to break the coating. The invention of Patent Document 2 does not consider breaking the insulator. In addition, any of the inventions of Patent Document 1, Patent Document 2, and Patent Document 3 still have the coating scraps peeled off, which may hinder conduction. Furthermore, a sufficient contact area cannot be ensured only by the protrusions and protrusions contacting the substrate circuit.

  The present invention has been made to solve the above-mentioned problems, and its object is to provide a fastening method, a washer, and an auxiliary device capable of obtaining reliable conduction even when an insulator is applied to the surface of an object to be fastened. To provide a washer.

  In order to achieve the above object, the invention according to claim 1 is characterized in that the object to be fastened with the circuit pattern formed thereon is coated on the circuit pattern using a washer provided with a protrusion on at least one surface. In the fastening method for securing the electrical connection with the circuit pattern by peeling off, a groove is provided adjacent to the protrusion, and the radially inner end of the protrusion is rotated in the direction of tightening the screw from the radially outer end. The washer arranged on the side is arranged so that the ridge contacts the object to be fastened, and the outer diameter is larger than the washer and is bent to one surface side in the range from the outer diameter of the washer to the peripheral side. An auxiliary washer provided with a portion is disposed from above the washer so that the bent portion covers the washer, and the screw is passed through the auxiliary washer, the washer and the object to be fastened.

  Therefore, according to this method, since the radially inner end of the ridge is arranged on the rotational direction side when the screw is tightened from the radially outer end, the stripped coating waste is washed with the rotation of the screw. It can be swept out of the washer by rotating.

  In addition, since the groove is provided adjacent to the ridge, the coating waste can be efficiently swept out to the outside of the washer, and the ridge that is crushed as the screw tightens can be stored in the groove. it can.

  In addition, the auxiliary washer has an outer diameter larger than that of the washer, and is provided with a bent portion bent on one surface side in a range closer to the peripheral side than the outer diameter of the washer, and the bent portion is disposed so as to cover the washer. The coating waste put out from the washer can be held at the bent portion.

  According to a second aspect of the present invention, a ridge is provided on at least one surface in contact with an object to be fastened having a circuit pattern formed thereon, and the ridge peels off the coating on the circuit pattern and is electrically connected to the circuit pattern. In the washer for securing the groove, a groove is formed adjacent to the protrusion, and the radially inner end of the protrusion is disposed on the rotational direction side when the screw is tightened from the radially outer end.

  Therefore, since the radially inner end of the ridge is arranged on the rotational direction side when the screw is tightened from the radially outer end, the stripped coating debris is rotated outside the washer by rotating the washer as the screw rotates. Can be swept out. In addition, since the groove is provided adjacent to the ridge, the coating waste can be efficiently swept out to the outside of the washer, and the ridge that is crushed as the screw tightens can be stored in the groove. it can.

  The invention according to claim 3 is the invention according to claim 2, wherein the protrusion is formed of a material different from the base material of the washer, and is harder than the coating and softer than the circuit pattern. .

  Therefore, as the screw tightening proceeds, the protrusion can be easily crushed and stored in the groove. Moreover, there is little possibility of damaging a circuit pattern.

  According to a fourth aspect of the invention, in the invention of the second or third aspect, the surface of the washer provided with the protrusions is formed such that the center side swells from the peripheral side.

  Therefore, it is suitable for sweeping coating waste to the outside of the washer.

According to a fifth aspect of the present invention, a protrusion is provided on at least one surface in contact with an object to be fastened on which a circuit pattern is formed, and the coating on the circuit pattern is peeled off to ensure electrical connection with the circuit pattern. A groove is formed adjacent to the ridge, and a radially inner end of the ridge is a washer disposed on the rotational direction side when tightening a screw from a radially outer end ,
The outer diameter is larger than that of the washer, and is a fastening object including an auxiliary washer provided with a bent portion that is bent toward one surface in a range closer to the peripheral side than the outer diameter of the washer .

  Therefore, the coating waste put out from the washer can be held at the bent portion.

  As described in detail above, according to the first to fifth aspects of the present invention, a fastening method capable of obtaining reliable conduction even when an insulator is applied to the surface of the object to be fastened, a washer, An auxiliary washer can be provided.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing a configuration of a fastening portion. A casing 2 (not shown) is provided with a pedestal 2 to which a substrate 1 as an object to be fastened is attached, and a female screw 21 is provided at the tip of the pedestal 2. The base 2 is a conductor. The substrate 1 is provided with a copper foil 3 as a circuit pattern. The surface of the substrate 1 is coated with a coating (not shown) from above the copper foil 3. The coating is an insulator, such as an acrylic resin, a urethane resin, an epoxy resin, or a silicon resin. A mounting hole 5 is provided in the substrate 1 through the copper foil 3.

  A washer 6 is disposed at a position corresponding to the mounting hole 5. Further, the auxiliary washer 7 is disposed from above the washer so as to cover the washer 6. Then, the substrate 1 is fixed by passing the auxiliary washer 7, the washer 6 and the substrate 1 and fastening the screw 8 to the female screw 21.

  FIG. 2 is a perspective view of the washer 6. Twelve protrusions 61 are equally provided on one surface of the washer 6. In FIG. 1, the washer 6 is disposed so that the ridge 61 contacts the substrate 1. The protrusion 61 is made of a material different from the base material, is harder than the coating and softer than the copper foil 3, and is solder in this embodiment. The protrusion 61 is formed by transfer or vapor deposition. A groove 62 is formed in the washer 6 adjacent to each protrusion 61. In the present embodiment, the protrusion 61 and the groove 62 are linear, and the adjacent protrusion 61 and the groove 62 are formed in parallel.

  FIG. 3 is a plan view of the surface of the washer 6 on which the ridges 61 are provided. In this embodiment, the direction of rotation when tightening the screw 8 is the direction of the arrow in FIG. The radially inner end 611 of the protrusion 61 is disposed at a position on the rotational direction side when the screw 8 is tightened from the radially outer end 612. That is, in FIG. 3, the line connecting the center of the washer 6 and the radially inner end 611 is arranged in the direction of the arrow from the line connecting the center of the washer 6 and the radially outer end 612.

  4 is a cross-sectional view of the washer 6 taken along the line AA in FIG. However, the protrusion 61 and the groove 62 are omitted, and the cross-sectional shape of the base material of the washer 6 is schematically shown. In FIG. 4, the top is the surface on which the protrusions 61 are provided. The washer 6 is formed such that the center side swells from the peripheral side on the surface on which the protrusion 61 is provided.

FIG. 5 is a partial cross-sectional view taken along line BB in FIG. 3 and shows detailed shapes of the protrusion 61 and the groove 62. In the present embodiment, the protrusion 61 has a rectangular cross-sectional shape. Further, in this embodiment, the groove 62 is formed at a position close to the rotation direction side of the protrusion 61. FIG. 6 is a schematic cross-sectional view showing a state after the screw 8 is tightened. FIG. 7 is a detailed view of C in FIG. However, the hatching of the substrate 1 and the copper foil 3 are omitted. The auxiliary washer 7 has an outer diameter larger than that of the washer 6, and is provided with a bent portion 71 that is bent in a range closer to the peripheral side than the outer diameter of the washer 6. The auxiliary washer 7 is disposed from above the washer so that the bent portion 71 covers the washer 6. In other words, the washer 6 is placed in a recess formed by the bent portion 71.

  Next, the operation of the present embodiment configured as described above will be described.

  As shown in FIG. 1, the screw 8 is fastened to the female screw 21 through the auxiliary washer 7, the washer 6, and the substrate 1. When the screw 8 is tightened, the washer 6 is pressed against the substrate 1. At this time, a frictional force is generated between the umbrella portion of the screw 8 and the auxiliary washer 7 and between the auxiliary washer 7 and the washer 6, and the washer 6 rotates with the screw 8 relative to the substrate 1.

  Here, the radially inner end 611 of the ridge 61 provided on the washer 6 is disposed on the rotational direction side when the screw is tightened from the radially outer end 612, and the ridge 61 is disposed on the substrate 1. It is arranged to touch. Accordingly, when the washer 6 rotates with respect to the substrate 1, the coating on the surface of the substrate 1 is peeled off by the protrusion 61. The stripped coating scraps 41 are sequentially swept from the radially inner end 611 to the radially outer end 612 and to the outside of the washer 6.

  Further, the washer 6 is formed such that the center side of the surface on which the protrusion 61 is provided swells from the peripheral side. Accordingly, the coating is peeled off sequentially from the center side. This bulge is crushed as the screw 8 is tightened.

  Moreover, the groove part 62 is formed adjacent to the protrusion 61, and the coating waste 41 is efficiently swept out.

  When the screw 8 is further tightened, the washer 6 is strongly pressed against the substrate 1. At this time, the material of the protrusion 61 is formed of a material different from the base material, and is harder than the coating and softer than the copper foil 3. Therefore, even if the protrusion 61 is strongly pressed against the substrate 1, the copper foil 3 is prevented from being peeled off. The ridge 61 is crushed between the base metal of the washer 6 and the copper foil 3 and stored in the groove 62.

  On the other hand, as shown in FIG. 7, the sputtered coating waste 41 is prevented from being scattered around by the bent portion 71 of the auxiliary washer 7.

  The present embodiment has the following effects.

  (1) The radially inner end 611 of the ridge 61 provided on the washer 6 is arranged on the rotational direction side when the screw is tightened from the radially outer end 612, and the stripped coating waste 41 is Sweeping is sequentially performed from the radially inner end 611 to the radially outer end 612 and then to the outside of the washer 6.

  Therefore, it is suppressed that the coating waste 41 prevents conduction, and reliable conduction can be obtained.

  (2) The washer 6 is formed such that the center side of the surface on which the ridge 61 is provided swells from the peripheral side, and the coating is peeled off sequentially from the center side.

  Therefore, it is suitable for sweeping the coating waste 41 to the outside of the washer 6.

  (3) The groove 62 is formed adjacent to the protrusion 61.

  Therefore, the coating waste 41 can be efficiently swept out. Moreover, since the groove part 62 is formed in parallel with the adjacent protrusion 61, it is more suitable to sweep out the coating waste 41.

  (4) Since the material of the protrusion 61 is formed of a material different from the base material and is harder than the coating and softer than the copper foil 3, the copper foil 3 is prevented from being peeled off.

  Therefore, reliable conduction can be obtained.

  (5) The groove 62 is formed adjacent to the protrusion 61, and the protrusion 61 is crushed between the base material of the washer 6 and the copper foil 3 and is accommodated in the groove 62.

  Therefore, the contact area between the washer 6 and the copper foil 3 can be increased, and reliable conduction can be obtained.

  (6) The material of the protrusion 61 is formed of solder.

  Therefore, even if the protrusion 61 is crushed and cannot be accommodated in the groove 62 and is interposed between the copper foil 3 and the base metal of the washer 6, the resistance value is low and there is no possibility of preventing conduction.

  (7) The scattered coating waste 41 is prevented from being scattered by the bent portion 71 of the auxiliary washer 7.

  Therefore, it is suppressed that the coating waste 41 scatters and adversely affects multiple parts. Moreover, even when the copper foil 3 is peeled off, it is possible to suppress scattering of the scraps of the copper foil 3 and to suppress a short circuit of multiple components.

  The embodiment is not limited to the above, and may be configured as follows, for example.

  In the present embodiment, the protrusion 61 is made of a material different from the base material of the washer 6. However, the same material may be used, and in this case, it may be formed integrally.

  In the present embodiment, the protrusion 61 is made of solder, but is not limited to this. Any material that is harder than the coating and softer than the copper foil 3 may be used.

  ○ In the present embodiment, the protrusion 61 and the groove 62 are formed in a straight line, but the present invention is not limited to this. It may be a curve. The radially inner end 611 of the ridge 61 may be disposed on the rotational direction side when the screw is tightened from the radially outer end 612.

  In the present embodiment, the adjacent protrusion 61 and the groove 62 are formed in parallel, but the present invention is not limited to this.

  ○ In the present embodiment, the protrusion 61 has a rectangular cross-sectional shape, but is not limited to this. For example, a triangular cross-sectional shape may be used.

  In the present embodiment, the washer 6 is formed such that the center side of the surface on which the ridges 61 are provided swells from the peripheral side, but is not limited thereto. It may be flat without swelling.

  In the present embodiment, the auxiliary washer 7 has a bent portion formed at only one portion of the bent portion 71, but is not limited to this. For example, a bent portion may be further formed outside the bent portion 71 as shown in FIG. FIG. 8 is a schematic cross-sectional view showing another embodiment of the auxiliary washer 7. However, hatching is omitted.

  As shown in FIG. 9, the conductive terminal 9 and the flat washer 10 may be put on the auxiliary washer 7 and the screw 8 may be tightened.

  In the present embodiment, the groove 62 is formed at a position close to the rotation direction side of the protrusion 61, but is not limited thereto. It may be close to the direction opposite to the rotation direction or may be an intermediate position.

  In this embodiment, the washer 6 and the auxiliary washer 7 are used simultaneously, but only the washer 6 may be used.

The perspective view which shows the structure of embodiment. The perspective view of a washer. The top view of the surface in which the protrusion of the washer was provided. FIG. 4 is a schematic cross-sectional view of a washer at A-A in FIG. 3. The fragmentary sectional view of the washer in BB of FIG. The schematic cross section which shows the state after tightening a screw. FIG. 7 is a detailed view at C in FIG. 6. The schematic cross section which shows another embodiment of an auxiliary washer. The perspective view which shows the structure of another embodiment. The schematic cross section which shows a prior art.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Board | substrate as to-be-fastened object, 3 ... Copper foil as a circuit pattern, 6 ... Washer, 61 ... Projection, 611 ... Radial inner side edge part, 612 ... Radial direction outer edge part, 62 ... Groove part, 7 ... Auxiliary Washer, 71 ... bending part, 8 ... screw.

Claims (5)

In the fastening method in which the object on which the circuit pattern is formed is peeled off the coating on the circuit pattern by using a washer provided with a protrusion on at least one surface, and the conduction with the circuit pattern is ensured.
A groove is provided adjacent to the protrusion, and the inner end of the protrusion in the radial direction is fastened to the washer arranged on the rotation direction side when the screw is tightened from the outer end of the radial direction. Place it in contact with things,
An auxiliary washer having an outer diameter larger than that of the washer and a bent portion bent on one side in a range from the outer diameter of the washer to the peripheral side is provided above the washer so that the bent portion covers the washer. Place and
A fastening method for ensuring electrical continuity, wherein the screw is passed through the auxiliary washer, the washer and the object to be fastened. In a washer that a protrusion is provided on at least one surface in contact with an object to be fastened with a circuit pattern, and the protrusion strips off the coating on the circuit pattern to ensure conduction with the circuit pattern,
A groove is formed adjacent to the ridge,
The washer characterized in that the radially inner end of the ridge is arranged on the rotational direction side when the screw is tightened from the radially outer end. The washer according to claim 2, wherein the protrusion is made of a material different from a base material of the washer, and is harder than the coating and softer than the circuit pattern. The washer according to claim 2 or 3, wherein the surface of the washer on which the protrusion is provided is formed such that the center side swells from the peripheral side. A protrusion is provided on at least one surface in contact with an object to be fastened with a circuit pattern formed thereon, and the coating on the circuit pattern is peeled off to ensure electrical connection with the circuit pattern, and a groove portion is adjacent to the protrusion. A washer that is formed and is disposed on the rotational side when the screw is tightened from the radially outer end, and whose outer diameter is larger than that of the washer and is larger than the outer diameter of the washer. An auxiliary washer provided with a bent portion bent on one side in the range of the edge side ;
Fastening consisting of

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