JP2013257013A - Fastening method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fastening method with which metallic members with an electrically insulating coating applied therebetween, can be conducted and fastened by the use of a screw.SOLUTION: A fastening method includes fastening a metallic plate member 6 having an electrically insulating coating film 6a applied to the surface and having an insertion hole 61 for inserting a screw 1, to a metallic fastening object member 7 where a screw hole 71 for screwing the screw 1 is formed, by the use of the screw 1. The seat surface 21 of the screw 1 has a projection 5 at a position where the seat surface 21 is opposed to the periphery of the insertion hole 61. When the screw 1 is fastened, the projection 5 breaks the coating film 6a of the metallic plate member 6 by the contact between the seat surface 21 and the periphery of the insertion hole 61; and thereby, the metallic plate member 6 and the fastening object member 7 can be electrically conducted and fastened via the screw 1.

Description

  The present invention relates to a fastening method for fastening a plurality of metal members with screws.

  Conventionally, for example, in a lighting device including a power supply device, the power supply device may be housed in an outer shell member configured by mechanically connecting a plurality of metal members (see, for example, Patent Document 1). . At this time, the outer shell member around the power supply device needs to have the same potential for safety. Further, when the outer shell member is grounded (grounded) to the outside, it is necessary that the plurality of metal members are electrically connected to each other.

Patent No. 04057872

  As a method of fastening a plurality of metal members, a method of fastening with screws is usually used. However, the metal member may be coated on the surface in advance to improve the appearance, or may be coated with a ceramic film in order to improve heat dissipation by radiation. That is, when metal members having a coating having electrical insulation on the surface are fastened with each other, an electrical insulation coating is interposed between the plurality of metal members if the screws are simply fastened with screws. There is a problem that continuity cannot be obtained.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for easily conducting and fastening metal members each having an electrically insulating coating therebetween using screws. To do.

  The fastening method according to the present invention includes a metal plate member having an electrically insulating coating applied to the surface and having a through hole for inserting a screw, and a screw hole into which the screw is screwed. A fastening method for fastening a fastening member with the screw, wherein the seat surface of the screw or the metal plate member has a protrusion at a position facing the periphery of the insertion hole and the seat surface, and fastens the screw. In this case, the projection is brought into contact with the seat surface or the periphery of the insertion hole to break the coating on the metal plate member, thereby electrically connecting the metal plate member and the member to be fastened via the screw. It is characterized by electrically conducting and fastening.

  In the present invention, even if a film having electrical insulation properties is interposed between the metal plate member and the member to be fastened, the metal plate member and It is possible to electrically connect the member to be fastened.

  The fastening method according to the present invention is characterized in that the projecting portion is provided on a peripheral edge of the insertion hole so as to protrude to a side through which the screw is inserted.

  In the present invention, the protrusion can be easily formed on the periphery of the insertion hole, and even if the screw does not have the protrusion, the protrusion can be easily connected to the metal plate member via the screw. It is possible to electrically connect the member to be fastened.

  In the fastening method according to the present invention, the screw has a countersunk head having a substantially conical surface as the seating surface, and the metal plate member is thinned as the insertion hole approaches the insertion hole. And the protrusion is provided on a peripheral edge of the insertion hole.

  In the present invention, since the peripheral edge of the insertion hole is formed thin by the taper portion, the projection portion can be easily formed with a small force.

  The fastening method according to the present invention is characterized in that the protrusion is partially provided on the periphery of the insertion hole.

  In the present invention, since the protrusion is partially provided on the periphery of the insertion hole, the coating film of the minimum area applied to the surface of the protrusion is intensively scraped off by the screw seat surface. Therefore, the metal plate member and the member to be fastened can be electrically connected easily with a small force.

  Metal members having an electrically insulating coating therebetween can be easily conducted and fastened with screws.

It is explanatory drawing which shows the fastening method which concerns on Embodiment 1 of this invention, (a) shows the state by which the screw is not fastened, (b) shows the state by which the screw was fastened. It is explanatory drawing which shows the fastening method which concerns on Embodiment 2 of this invention, (a) shows the state by which the screw is not fastened, (b) shows the state by which the screw was fastened. It is explanatory drawing which shows the fastening method which concerns on Embodiment 3 of this invention, (a) shows the state which the screw is not fastened, (b) shows the fastened state. (A) is explanatory drawing which shows the formation method of the projection part provided in the insertion hole which concerns on FIG. 3, (b) is the top view which looked at the insertion hole provided with the projection part from the insertion direction of the screw. .

Embodiment 1
Embodiment 1 of the fastening method of the metal member which concerns on this invention is demonstrated based on FIG. 1A and 1B are explanatory views showing a fastening method according to the first embodiment. FIG. 1A shows a state where the screw 1 is not fastened, and FIG. 1B shows a state where the screw 1 is fastened.

  As shown in FIG. 1, the screw 1 of the present embodiment has a metal plate member 6 provided with an insertion hole 61 through which the screw 1 is inserted into a fastened member 7 made of a metal plate member provided with a screw hole 71. Is fastened, and the fastened member 7 and the metal plate member 6 are fastened and mechanically connected by the screw 1.

The screw 1 includes a head 2 in which a groove that fits the tip of a tool such as a screwdriver is formed on the top surface 22, a screw part 3 in which a screw groove is cut in a cylindrical member, and a head 2 and a screw part. 3 has a cylindrical portion 4 that connects the three. The screw 1 is made of a metal material having conductivity such as iron, aluminum, copper, etc. The head 2 has a plurality of protrusions 5 projecting on a seating surface 21 that is a flat surface on the direction in which the screw 1 is screwed. It is installed. The protrusions 5 are provided at positions opposed to the periphery of the insertion hole 61 of the metal plate member 6 described later, and are provided at two locations in the circumferential direction of the seat surface 21 at substantially equal intervals. The number of protrusions 5 formed may be one or three or more. Further, the position where the protrusion 5 is provided on the seat surface 21 is not particularly limited. The protrusion 5 is provided so as to protrude from the thickness of a coating film 6a described later.

  The metal plate member 6 is a plate-like member made of a metal material having conductivity such as iron, aluminum, or copper. The metal plate member 6 is formed with an insertion hole 61 that penetrates in the thickness direction of the metal plate member and through which the screw portion 3 and the cylindrical portion 4 of the screw 1 are inserted. Note that no screw groove is formed in the insertion hole 61.

  The metal plate member 6 is coated with a coating film 6a over the entire surface. The coating film 6a is applied to the inner peripheral surface of the insertion hole 61 and the surface on the fastened member 7 side. Therefore, in the state where the metal plate member 6 and the member to be fastened 7 are brought into surface contact with each other and the screw 1 is not fastened as shown in FIG. 1A, the coating film 6a is interposed therebetween, The metal plate member 6 and the fastened member 7 are not electrically connected but are insulated.

  Similar to the metal plate member 6, the fastened member 7 is a plate-like member made of a metal material having conductivity such as iron, aluminum, or copper. In addition, the to-be-fastened member 7 does not need to be a plate-shaped member. A screw hole 71 in which a screw groove for screwing the screw 1 is cut is formed in the fastened member 7. The screw 1 mounts the metal plate member 6 on the member 7 to be fastened, and is screwed into the screw hole 71 in a state where the insertion hole 61 and the screw hole 71 are aligned, thereby fastening both members.

  The to-be-fastened member 7 is coated with a coating film 7 a over the entire surface in the same manner as the metal plate member 6. Since the screw hole 71 is formed after the coating film 7 a is applied or masked during coating, the coating film 7 a is not applied to the inner peripheral surface of the screw hole 71. That is, in a state where the screw 1 is fastened to the screw hole 71, the screw 1 and the member to be fastened 7 are electrically connected to each other by contact between the screw groove of the screw hole 71 and the screw groove of the screw portion 3.

FIG. 1B shows a state in which the screw 1 fastens and fixes the metal plate member 6 to the fastened member 7. When the screw 1 is screwed into the screw hole 71, the protrusion 5 comes into contact with the coating film 6 a applied to the surface of the metal plate member 6, and further presses the seating surface 21 of the screw 1 against the surface of the metal plate member 6. Thus, the protrusion 5 breaks the coating film 6a, and the metal surface inside the coating film 6a and the protrusion 5 come into contact with each other, whereby the screw 1 and the metal plate member 6 are electrically connected. As described above, in the fastening state of FIG. 1B, the screw 1 and the member to be fastened 7 are electrically connected, so that the metal plate member 6 and the member to be fastened 7 are electrically connected via the screw 1. Therefore, according to the fastening method of the present invention, the metal plate member 6 to which the electrically insulating coating (paint film) is applied and the member to be fastened 7 can be set to the same potential, and the metal plate member 6 can be safely provided. In addition, the fastened member 7 can be grounded.
[Embodiment 2]
Next, Embodiment 2 of the metal member fastening method according to the present invention will be described with reference to FIG. 2A and 2B are explanatory views showing a fastening method according to the second embodiment, in which FIG. 2A shows a state where the screw 1 is not fastened, and FIG. 2B shows a state where the screw 1 is fastened. In addition, about the part same as Embodiment 1, it attaches | subjects and demonstrates the same code | symbol, and abbreviate | omits detailed description.

  As shown in FIG. 2A, the screw 1 of the present embodiment is different from the head 2 of the first embodiment in the shape of the head 8 of the screw 1. The head 8 has a countersunk head shape having a substantially conical surface whose diameter increases as the seating surface 81 moves toward the top surface 82 side. That is, the screw 1 is a so-called countersunk screw. The top surface 82 has a flat shape, and the seat surface 81 is provided with a plurality of protrusions 5.

  In addition, the metal plate member 6 is provided with a taper portion 62 that becomes thinner around the insertion hole 61 as it approaches the insertion hole in the radial direction. The tapered portion 62 forms a substantially conical surface similarly to the shape of the seating surface 81.

As shown in FIG. 2 (b), in a state where the screw 1 fastens the metal plate member 6 to the fastened member 7, the seat surface 81 is in surface contact with the tapered portion 62, and the top surface 82 is the surface of the metal plate member 6. And it will be in the same state. At this time, the protrusion 5 breaks the coating film 6 a applied to the surface of the tapered portion 62, whereby the screw 1 and the metal plate member 6 are electrically connected, and the metal plate member 6 and the fastening member 7 are electrically connected via the screw 1. Is electrically conducted.
[Embodiment 3]
Next, Embodiment 3 of the metal member fastening method according to the present invention will be described with reference to FIG. 3A and 3B are explanatory views showing a fastening method according to the third embodiment. FIG. 3A shows a state where the screw 1 is not fastened, and FIG. 3B shows a state where the screw 1 is fastened. In addition, about the part same as Embodiment 1 or Embodiment 2, it attaches | subjects and demonstrates the same code | symbol, and abbreviate | omits detailed description.

  As shown in FIG. 3A, the screw 1 of the third embodiment is a countersunk screw having a head 8 having the same shape as the screw 1 of the second embodiment. However, the screw 1 of the third embodiment is different from the second embodiment in that the protrusion 5 is not provided on the seat surface 81.

  Further, the metal plate member 6 has a protruding portion 9 that protrudes toward the seating surface 81 side of the screw 1, that is, the side through which the screw 1 is inserted, around the inner end of the tapered portion 62, that is, around the insertion hole 61. Yes. The protrusions 9 are provided at positions facing the seat surface 81, and specifically, four protrusions 9 are provided around the insertion hole 61. The number of protrusions 9 is not limited to four, and may be 1 to 3, or 5 or more. Further, the protrusion 9 may have a shape in which the periphery of the insertion hole 6 protrudes toward the seat surface 81 as a whole.

  As shown in FIG. 3B, the seat surface 81 is in surface contact with the tapered portion 62 and the top surface 82 is the surface of the metal plate member 6 when the screw 1 fastens the metal plate member 6 to the fastened member 7. And it will be in the same state. At this time, the protrusion 9 is brought into contact with and pressed against the seating surface 81, thereby breaking the coating film 6 a applied to the surface of the protrusion 9, and the screw 1 and the metal plate member 6 are electrically connected. The fastened member 7 is electrically connected via the screw 1.

  Next, a method for forming the protrusion 9 according to the third embodiment will be described with reference to FIG. 4A is an explanatory view showing a method of forming the projection 9 provided in the insertion hole 61 according to FIG. 3, and FIG. 4B shows the insertion hole 61 provided with the projection 9 in the screw 1. It is the top view seen from the insertion direction.

  First, the metal plate member 6 is formed with an insertion hole 61 and a tapered portion 62 into which the screw 1 as a countersunk screw can be inserted. Next, the coating film 6 a is applied to the metal plate member 6. Then, a thin rod-shaped tool 10 having a relatively sharp tip is inserted from the side opposite to the tapered portion 62 of the insertion hole 61, that is, the side of the surface placed on the fastened member 7, and the tip surface 11 of the tool 10 is inserted. It abuts on the periphery of the insertion hole 61. In the present embodiment, an example in which a plus dollar bar is used as the tool 10 will be described.

  Next, a strong force is applied so as to strike the tool 10 in the direction of the insertion hole 61 that is the direction of the arrow in FIG. 4A, and a force is applied to the peripheral edge of the insertion hole 61 at the tip surface 11 of the tool 10. Deform. Thereby, the periphery of the insertion hole 61 protrudes toward the taper part 62, and the projection part 9 is formed.

  When the tool 10 is a Phillips screwdriver, the tip has a cross-shaped convex shape, so that the protrusions 9 are provided at approximately equal intervals around the insertion hole 61 as shown in FIG. 4B. It will be. When the tool 10 is a flat-blade screwdriver, projections 9 are provided at two locations according to the shape of the tip, and in the case of a tool having a conical shape with a pointed tip, the projection around the entire insertion hole 61 is projected. 9 can be formed.

  As in the fastening method of the present embodiment, a protrusion that protrudes from the periphery of the insertion hole 61 is provided, and the coating film 6a can be easily broken by the force with which the screw 1 is screwed. Further, the projection 9 can be easily formed using the tool 10 without using the specially shaped screw 1 provided with the projection 5, and a highly convenient fastening method can be realized.

  In addition, the formation method of the projection part 9 is not restricted to the method of forming manually with the said tool 10, You may form when processing the metal plate member 6 previously.

  In the present embodiment, the protrusion 9 is provided around the insertion hole 61 provided with the tapered portion 62. However, the present invention is not limited to this, and the tapered portion 62 to which the screw 1 described in the first embodiment is attached is provided around the insertion hole 61. You may provide in the insertion hole 61 which is not formed in. However, when the protrusion 9 is formed in the insertion hole 61 provided with the taper portion 62 in the periphery, the protrusion 9 can be easily formed with a smaller force because the portion around the insertion hole 61 is thinner. Is advantageous.

  Furthermore, in comparison with the example in which the protrusions 5 described in the first and second embodiments are provided, the fastening method in which the protrusions 9 according to the third embodiment are provided can break the coating film 6a with less force. It is advantageous. This is because, in the case of the first and second embodiments, when the screw 1 is fastened, the protruding portion 5 breaks the coating film 6a so as to scrape the coating film 6a while drawing an arc, whereas the protruding portion 9 of the third embodiment has a protruding portion. This is because the coating film 6a having the minimum area formed at the tip of the sheet 9 can be intensively shaved by the seating surface 81, so that the force required to break the coating film 6a is small. Therefore, it is possible to more securely connect and fasten the metal plate member 6 and the fastened member 7 by providing the protrusion 9 around the insertion hole 61 in the third embodiment.

DESCRIPTION OF SYMBOLS 1 Screw 2 Head part 5, 9 Protrusion part 6 Metal plate member 6a Paint film 7 Fastened member 21, 81 Seat surface 61 Insertion hole 62 Taper part 71 Screw hole

Claims (4)

An electrically insulating coating is applied to the surface, and a metal plate member having an insertion hole for inserting a screw and a metal member to be fastened with a screw hole into which the screw is screwed are fastened by the screw. A fastening method,
The seat surface of the screw or the metal part plate member has a protrusion at a position facing the periphery of the insertion hole and the seat surface,
When the screw is fastened, the projection is brought into contact with the seat surface or the periphery of the insertion hole to break the coating of the metal plate member, so that the metal plate member and the fastened member are interposed via the screw. The fastening method characterized by electrically conducting and fastening with a member.   The fastening method according to claim 1, wherein the protrusion is provided on a peripheral edge of the insertion hole so as to protrude to a side through which the screw is inserted. The screw has a countersunk head having a substantially conical surface.
The metal plate member has a tapered portion that becomes thinner around the insertion hole as it approaches the insertion hole,
The fastening method according to claim 2, wherein the protrusion is provided on a peripheral edge of the insertion hole.   The fastening method according to claim 2, wherein the protrusion is partially provided on a peripheral edge of the insertion hole.