JP2007232067A - Boss member for positioning - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a boss member for positioning capable of reducing parts and decreasing cost for attaching a member to be fastened. <P>SOLUTION: The boss member has a shaft part 10, a head part 20 with a serration part 21 of which diameter is larger than that of the shaft part and a recessed part 15 formed at an outer circumference of the shaft part 10 near the head part 20. The shaft part 10 consists of a small diameter part 11 of which front end has a small diameter and a large diameter part 12 of which diameter from the small diameter part 11 to the recessed part 15 is larger than that of the small diameter part 11. A lower hole 14 for threading the fastening member is formed on a same center line of the large diameter part 12 and the small diameter part 11. An outer circumference of the small diameter part 11 is formed in a shape to which the positioning hole 3 of the member 2 to be fastened can fit. Thus, the positioning hole can be also used as an attaching hole, strength of the member to be fastened is prevented from lowering and operation cost can be reduced as the time required for operation is cut off as the number of holes provided in the member to be fastened is decreased. In addition, the number of the boss members and the fastening members for threading to them to be used is reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a boss member that is interposed between a work and a member to be fastened and fixed with a fastening member such as a screw or a nut when the member to be fastened is attached to the work. The present invention relates to a positioning boss member that is capable of accurately setting the position of the fastening member when the fastening member is fastened and enabling the fastening member to be screwed.

  When an electronic board is laminated to reduce the thickness of a product and a cover or a display unit is attached to the front surface, a relatively thin work is used as a work for attaching these members to be fastened. When attaching a fastening member such as an electronic board, a cover or a display unit to such a workpiece, a screw is usually used, but the thickness of the workpiece is not sufficient to screw this screw directly into the workpiece, The fixed strength was reduced. In order to prevent this, a boss member having sufficient strength for screwing and mounting the screw is fixed to the workpiece, and a fastening member is placed on the tip of the shaft portion of the boss member so that the screw is attached to the boss member. At present, the fastened member is attached by screwing into the formed prepared hole.

  Many kinds of boss members have been used recently. For example, a metal part has a head part slightly larger in diameter than a mounting hole (not shown) formed in the workpiece and a shaft part that is erected on the head part and has a diameter that can be fitted into the hole. It is formed integrally, and on the outer peripheral surface of the shaft part, a groove with a square cross section is formed on the entire circumference at the boundary with the head, and a knurl or serration for preventing rotation is formed on the outer peripheral surface of the head. There is something that was done. The shaft portion is formed with a bottomed cylindrical shape to which a screw can be screwed or a through hole shaped through hole penetrating from the shaft portion to the head.

  When such a boss member is press-fitted into and fixed to a work and a member to be fastened is attached thereto, an attachment method as shown in FIG. 5 is common. This figure is a plan view showing a state in which a fastened member 102 made of a rectangular plate material is attached to a work 104 with a boss member 105 interposed therebetween, and the boss member 105 fixed to the work 104 as shown by a broken line. The fastened member 102 is fixed by screws 130. In this case, the fastened member 102 is positioned by fitting the positioning holes 103 formed in the four corners thereof in advance with the positioning boss member 101 standing upright on the workpiece 104, and then the boss member 105 at the fastening position is positioned. A screw 130 is screwed into the prepared hole to fix the fastened member 102 to the workpiece 104.

Thus, after positioning with another member beforehand, the method of attaching a to-be-fastened member to a workpiece | work is normally utilized for many attachment operations, for example, there exists a thing as shown to patent 3448460 gazette. This relates to a mounting structure for an open lid used in a console box for a vehicle. As shown in FIG. 6, the mounting piece 202 of the hinge member 200 is attached to a bracket of the box body so as to be rotatable around a hinge pin. It is made to fit in the recessed part 206 for hinge attachment. That is, the positioning protrusion 201 of the outer lid body 204 is fitted into the positioning hole 203 of the mounting piece 202 of the hinge member 200, and the outer lid body 204 is hinged by the fitting action of the positioning protrusion 201 and the positioning hole 203. Member 200 is positioned. The attachment screw 230 is screwed into the attachment hole 210 of the boss portion 209 of the outer lid body 204 from the hole 207 of the attachment piece 202 of the hinge member 200 through the insertion hole 208 of the inner lid body 205.
Japanese Patent No. 3448460

  However, when fitting the positioning protrusion into the positioning hole of the mounting piece of the hinge member in this way, in order to screw the mounting screw, the positioning hole must be opened separately from the hole to be fastened. Many holes are required for the member to be fastened, and the strength of the member to be fastened is correspondingly reduced. Moreover, since many holes are drilled in the fastened member, the drilling work takes time and costs are increased. Furthermore, in order to maintain the strength, it is necessary to increase the thickness of the member to be fastened. However, if the size and weight of the assembled product are limited, the thickness is naturally limited, which also reduces the size and weight of the product. There are problems such as various adverse effects.

  An object of the present invention is to obtain a positioning boss member that solves such a problem and enables reduction of parts and reduction of the mounting cost of a fastened member.

  An object of the present invention is to provide a shaft 10 to which a fastening member is screwed, a head 20 having a serration portion 21 which is integral with the shaft 10 and has a larger diameter, and a shaft 10 adjacent to the head 20. The boss member is provided with a groove-shaped recess 15 on the outer periphery thereof, and the shaft portion 10 has a small-diameter portion 11 having a small tip and a large diameter larger than the small-diameter portion 11 from the small-diameter portion 11 to the recess 15. And a pilot hole 14 into which the fastening member is screwed on the same center line of the large-diameter portion 12 and the small-diameter portion 11, and the outer periphery of the small-diameter portion 11 is formed in the fastened member 2. This is achieved by providing a positioning boss member in which the positioning hole 3 formed can be fitted.

  In order to achieve this object, in addition to the configuration of the positioning boss member, the fastened member 2 guided by the small diameter portion 11 is placed between the large diameter portion 12 and the small diameter portion 11 of the shaft portion. Since it has the step part 13 which formed the seat surface to be performed, it also becomes possible to fix this with positioning of the to-be-fastened member 2. As shown in FIG. In addition, since the recess has a side wall 16 that is inclined so that the bottom surface side is narrow and the open side is wide in the cross section along the axis, the thickness of the workpiece is reduced when the boss member is fixed to the workpiece. It is easy to fit into the recess, and the work and the boss member are firmly fixed.

  According to the present invention, when the member to be fastened is fixed to the workpiece for the purpose of laminating the electronic substrates on which the electronic components are arranged, the positioning protrusion is fitted into the positioning hole opened in the member to be fastened. Then, compared with the case where the screw is screwed through the assembly hole separately provided in the member to be fastened and the member to be fastened is fixed, the positioning hole can also be used as the assembly hole, so that the strength of the member to be fastened is reduced. Is blocked. Further, since the number of holes to be tightened is reduced, the time required for the work is shortened, and the work cost can be reduced. Furthermore, the number of boss members that are press-fitted and fixed to the workpiece and fastening members that are screwed to the boss members are also reduced. In this way, since the number of assembly holes for fixing the fastened members is reduced, especially when manufacturing an electronic board on which electronic wiring is provided, the number and positions of the assembly holes are reduced. Design becomes easy. Moreover, it is not necessary to increase the thickness of the member to be fastened more than necessary in order to maintain the strength of the member to be fastened. For this reason, according to the size of the assembly product assembled using this member to be fastened, The thickness can also be changed, and a specific effect such as no influence on the reduction in size and weight of the product can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 2 and 3, reference numeral 1 denotes a positioning boss member according to the present invention, which includes a shaft portion 10 and a head portion 20 having a diameter larger than that of the shaft portion 10. A shaft portion 10 of the boss member 1 includes a small diameter portion 11 having a small tip, and a large diameter portion 12 having a diameter larger than the small diameter portion 11 from the small diameter portion 11 to the head side. A stepped portion 13 having a flat seating surface is formed between the large diameter portion 12 and the small diameter portion 11. As shown in FIG. 1, the small-diameter portion 11 has a height equal to or lower than the thickness of the fastened member 2 such as an electronic board placed on the seat surface. Is placed on the seat surface such that the small diameter portion 11 does not protrude from the fastened member 2. In addition, the outer periphery of the small-diameter portion 11 has a shape in which the positioning hole 3 formed in the fastened member 2 can be fitted, that is, a circular shape in this embodiment. Although this shape is not particularly limited, in order to give the positioning boss member 1 a detent function, it may be oval or polygonal, and the positioning hole 3 may be shaped accordingly.

  On the other hand, a bottomed bottom hole 14 is formed from the small diameter portion 11 to the head side on the same center line of the large diameter portion 12 and the small diameter portion 11 of the positioning boss member 1. Although this pilot hole 14 is formed in a bottomed cylindrical hole shape, it may have a through hole shape (not shown) penetrating through the head end. A tapping screw 30 as a fastening member is screwed and combined with the prepared hole 14 so that the fastened member 2 is fixed. Therefore, the diameter of the prepared hole 14 is the leg portion of the tapping screw 30. The effective diameter of the thread formed on 31 is substantially the same diameter or smaller.

  Further, the neck portion between the shaft portion 10 and the head portion 20, that is, the shaft portion 10 close to the head portion 20, has a smaller diameter and a width of about ½ of the thickness of the head portion 20. In addition, a recess 15 having an outer peripheral groove shape along the outer periphery of the shaft portion is formed. In the cross section along the axis, the recess 15 has a side wall 16 inclined at least one or both sides so that the bottom side is narrow and the open side is wide. The concave portion 15 is a groove into which the meat of the workpiece 4 is fitted when the positioning boss member 1 is press-fitted and fixed in a mounting hole (not shown) of the workpiece 4 such as a metal plate. ing.

  The head portion 20 having a diameter larger than the diameter of the shaft portion 10 is continuously and integrally provided at the neck portion, and the head portion 20 is radially spaced from the center thereof at equal intervals on the circumference. A serration portion 21 having a shape in which a plurality of chevron-shaped protrusions protrudes is formed. The serration portion 21 has a serrated chevron shape on the outer periphery. However, the serration portion 21 is not limited to this shape. There may be.

  In such a configuration, the head 20 of the positioning boss member 1 is press-fitted and fixed in a mounting hole previously drilled at a predetermined position of the workpiece 4 and is positioned on the fastened member 2 to be mounted and fixed thereto, for example, In the embodiment, as shown in FIG. 5, the positioning holes 3 having such a size that the small-diameter portions 11 of the boss members 1 are fitted are formed at the four corners of the fastened member as in the conventional case.

  Thereafter, as shown in FIG. 4, the positioning hole 3 of the fastened member 2 is fitted into the small diameter portion 11 of the positioning boss member 1, and the tapping screw 30 is inserted into the prepared hole 14 of the boss member 1 from the fastened member side. Screw together. Thereby, the tapping screw 30 is screwed together while forming a female screw in the prepared hole 14. The tapping screw 30 used for this work is coated with an adsorbent 32 that prevents the powdered powder generated when the female screw is formed from the tip to the middle and screwed together, and adsorbs it. . This prevents the molding powder from scattering on the fastened member 2 such as an electronic substrate.

  Since the four corners of the fastened member 2 are fixed by this operation, the small-diameter portion 11 like the positioning boss member 1 fixed to a necessary portion for fixing the fastened member 2 to the work 4 is not provided. In the same manner as described above, the tapping screw 30 is screwed into the pilot hole of the boss member through the assembly hole (not shown) of the fastened member 2 which is opened so as to match the position where the boss member (not shown) stands upright. Fix together. Thereby, the assembly | attachment to the workpiece | work 4 of the to-be-fastened member 2 will be completed.

  Although the tapping screw 30 is used as the fastening member used in this embodiment, if a female screw (not shown) is formed in the pilot hole 14 of the boss member 1, it is a normal screw. In addition, if a male screw (not shown) is formed on the outer periphery of the small-diameter portion 11 of the positioning boss member 1 and the small-diameter portion 11 protrudes from the fastened member 2, a nut (not shown) may be used. ).

It is a principal part cross-sectional front view which shows the state which fixed the to-be-fastened member to the workpiece | work. It is a partial cross section front view of a positioning boss member. It is a top view of FIG. It is a principal part sectional front view which shows the screwing start state of a tapping screw. It is a top view which shows the fastening state of a workpiece | work and a to-be-fastened member. It is principal part sectional drawing which shows the prior art example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Positioning boss member 2 Fastened member 3 Positioning hole 4 Workpiece 10 Shaft part 11 Small diameter part 12 Large diameter part 13 Stepped part 14 Pilot hole 15 Recess 16 Side wall 20 Head 21 Serration part 30 Tapping screw 31 Leg part 32 Adsorbent

Claims (3)

  On the outer periphery of the shaft portion (10) to which the fastening member is screwed, the head portion (20) having a serration portion (21) which is integral with the shaft portion and larger in diameter, and the shaft portion adjacent to the head portion A boss member provided with a groove-shaped recess (15), wherein the shaft portion has a small-diameter portion (11) having a small tip, and a large-diameter portion (12 having a larger diameter than the small-diameter portion from the small-diameter portion to the recess). ) And a pilot hole (14) into which the fastening member is screwed is formed on the same center line of the large diameter portion and the small diameter portion, and the outer periphery of the small diameter portion is formed in the fastened member (2). A positioning boss member, wherein the positioning hole (3) is formed in a shape that can be fitted.   The shaft portion has a stepped portion (13) forming a seat surface on which a fastened member guided by the small diameter portion is placed between the large diameter portion and the small diameter portion. Item 2. A positioning boss member according to item 1. The positioning boss member according to claim 1 or 2, wherein the recess has a side wall (16) inclined at least one so that the bottom surface side is narrow and the open side is wide in a cross section along the axis.

Images