JP2013104494A - Thin plate fixing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To firmly fix thin plates to each other without looseness by a screw member causing no increase in the number of part items and no impairment in the flatness of the thin plates.SOLUTION: The thin plate 1 is formed with a first restriction part 11 of truncated cone shape projected to the side opposite to the contact surface side with the thin plate 2a, and a through-hole 12 with a diameter larger than the diameter of a shank 31 of the screw member 3 is formed in the center of the first restriction part 11. The thin plate 2a is formed with a fastening hole 21 into which the shank 31 of the screw member 3 is screwed, and a groove 22 having a diameter larger than the diameter of the first restriction part 11 and formed in concentric circle shape with respect to the fastening hole 21. The thin plate 1 and the thin plate 2a are placed to overlap so that the center axes of the through hole 12 of the thin plate 1 and the fastening hole 21 of the thin plate 2a are coincident, and the shank 31 of the screw member 3 is allowed to pass from the first thin plate side and screwed into the fastening hole 21 of the thin plate 2a to fix the thin plate 1 to the thin plate 2a by the screw member 3.

Description

  The present invention relates to a structure in which stacked thin plates are fixed with a screw member.

  A thin plate such as a sheet metal is often used for a housing of an electronic device or the like, and the thin plates are usually joined with each other by overlapping the thin plates with a screw member. Further, in order to increase the fastening strength between the thin plates, the peripheral portion of the screw hole of the thin plate is raised by burring to form a cylindrical portion (hereinafter sometimes referred to as “burring portion”), and the screw member and the thin plate It is also performed to lengthen the threaded part.

  For example, Patent Document 1 proposes a thin plate fastening method in which a burring portion protrudes toward a coupling partner side, and a mounting hole on the coupling partner side has an inner diameter that allows the burring portion to be fitted by clearance fit.

Japanese Patent Laid-Open No. 2001-214911

  In the proposed technique, although the burring portion is hardly deformed in the radial direction, when there are a plurality of fastening portions by the screw members, high accuracy is required for the formation position of the burring portion and the mounting hole.

  Conventionally, a spring washer is also inserted between the head of the screw member and the thin plate in order to increase the fastening strength between the thin plates, but the number of parts increases and the fastening operation becomes complicated.

  The present invention has been made in view of such conventional problems, and the object thereof is to securely tighten the thin members without loosening the thin plates without increasing the number of parts and without impairing the flatness of the thin plates. It is to provide a fixing structure that can be fixed with

  According to the present invention, the first thin plate in which the through hole is formed and the second thin plate in which the tightening hole is formed are overlapped so that the central axes of the through hole and the tightening hole are substantially coincided with each other. The structure is such that the shaft of the screw member is passed from the thin plate side and screwed into the fastening hole of the second thin plate, and the thin plates are fixed with the screw member, and the through hole of the first thin plate and the fastening hole of the second thin plate are A narrowed portion that protrudes outward is formed in at least one of the first thin plate and the second thin plate so that a space is formed between them, and a groove concentric with the tightening hole is formed in the second thin plate. A thin plate fixing structure is provided.

  In this case, the first thin plate may be provided with a first conical or columnar first diaphragm portion protruding outward, and the groove may be formed outside the first diaphragm portion.

  In addition, the first thin plate is provided with a first conical or columnar first diaphragm portion projecting outward, and the second thin plate is also provided with a second conical or cylindrical second diaphragm portion projecting outward. The diameter of the second throttle part may be smaller than the diameter of the first throttle part, and the groove may be formed outside the first throttle part.

  Further, the first thin plate is provided with a first conical or cylindrical first diaphragm portion protruding outward, and the second thin plate is provided with a third truncated conical or cylindrical shape projecting inward, The depth of the three throttle portions is made shallower than the depth of the first throttle portion, the diameter of the third throttle portion is made smaller than the diameter of the first throttle portion, and the groove is formed outside the first throttle portion. You may make it do.

  Further, a plurality of through holes may be formed at predetermined intervals in the circumferential direction so as to divide the groove.

  In the fixing structure according to the present invention, the throttle portion protruding outwardly in at least one of the first thin plate and the second thin plate so that a space is generated between the through hole of the first thin plate and the fastening hole of the second thin plate. And the second thin plate is bent inward of the space by fastening the screw member. When the second thin plate is bent, an elastic force is generated in the second thin plate to return to the original state, and the thin plates can be firmly fixed to each other with a screw member without increasing the number of parts. Moreover, since the groove | channel concentric with a fastening hole is formed in the 2nd thin plate, the bending of a 2nd thin plate is limited to an inner side part from a groove | channel, and the flatness of the other part of a 2nd thin plate is maintained. . Furthermore, when the first thin plate and the second thin plate are to move relative to each other in a direction perpendicular to the axial direction of the screw member, the second thin plate has a groove bent conically inward of the space. Since the friction between the inner portion and the first thin plate increases, the relative movement between the first thin plate and the second thin plate is remarkably suppressed as compared with the conventional case.

It is a vertical sectional view showing an embodiment of a fixing structure according to the present invention. It is a perspective view of the state which fixed the two thin board shown in FIG. 1 with the screw member. It is a perspective view of the 2nd thin plate in which the several through-hole was formed in the circumferential direction at predetermined intervals so that a groove | channel may be parted. It is a vertical sectional view showing other embodiments of the fixing structure according to the present invention. It is a perspective view of the state which fixed the two thin board shown in FIG. 4 with the screw member. It is a vertical sectional view showing other embodiments of the fixing structure according to the present invention. It is a perspective view of the state which fixed the two thin board shown in FIG. 6 with the screw member.

  Hereinafter, the thin plate fixing structure according to the present invention will be described in more detail with reference to the drawings. However, the present invention is not limited to these embodiments.

  1 and 2 show an embodiment of a thin plate fixing structure according to the present invention. FIG. 1 is a vertical sectional view when the thin plate 1 and the thin plate 2a are fixed by the screw member 3, and FIG. 2 is a perspective view.

  The thin plate 1 is formed with a frustum-shaped first diaphragm portion 11 that protrudes on the opposite side of the contact surface with the thin plate 2a. A through-hole 12 having a larger diameter is formed. On the other hand, the thin plate 2 a is formed with a fastening hole 21 into which the shaft portion 31 of the screw member 3 is screwed, and a groove 22 having a diameter larger than the diameter of the first throttle portion 11 concentrically with the fastening hole 21. . When the thin plate 1 and the thin plate 2a are overlapped so that the central axes of the through hole 12 of the thin plate 1 and the fastening hole 21 of the thin plate 2a coincide, the first throttle portion 11 is interposed between the thin plate 1 and the thin plate 2a. A space 4a is formed.

  And as shown to Fig.1 (a), the axial part 31 of the screw member 3 is passed from the 1st thin plate side, and is screwed by the fastening hole 21 of the thin plate 2a. When the screw member 3 is further tightened after the seating surface of the screw member 3 comes into contact with the thin plate 1, the fastening hole 21 portion of the thin plate 2 a is caused by the male thread of the screw member 3 as shown in FIG. Pulled up in the head direction, the inner part of the groove 22 bends in a conical shape toward the first thin plate with the fastening hole 21 as the center.

  When the inner portion of the thin plate 2a is bent more than the groove 22, an elastic force for returning to the original is generated in the thin plate 2a, and the fastening force between the screw member 3 and the thin plate 2a becomes stronger. Further, the bending of the thin plate 2a is limited to the inner portion of the groove 22, and the flatness of other portions of the thin plate 2a is maintained. Furthermore, since there is a gap between the shaft portion 31 of the screw member 3 and the through hole 12 of the thin plate 1, when a force perpendicular to the axial direction of the screw member 3 is applied to the thin plate 1 or the thin plate 2a, Although the thin plate 1 and the thin plate 2a can move relative to each other by the gap, if the inner portion of the thin plate 2a bends and the thin plate 1 and the thin plate 2a try to move relatively, the first throttle portion 11, the inner portion of the thin plate 2 a entering the inside of the thin plate 2 a comes into contact with the thin plate 1, so that the relative movement between the thin plate 1 and the thin plate 2 a is remarkably suppressed as compared with the conventional case.

  The depth of the first aperture 11 formed on the thin plate 1 may be appropriately determined in consideration of the material and thickness of the thin plate 1, the degree of bending of the thin plate 2a, and the like, but usually in the range of 0.5 mm to 5 mm. . The diameter of the first throttle portion 11 may be appropriately determined in consideration of the material, thickness, etc. of the thin plate 1, but is usually in the range of 3 to 6 times the diameter of the shaft portion 31 of the screw member 3. Is preferred.

  In addition, as a material of the thin plate 1 and the thin plate 2a, a conventionally known material such as a metal material or a resin material can be used, but the present invention is preferably applied when the rigidity of the thin plate 2a is lower than the rigidity of the thin plate 1. The From the viewpoint of bending the thin plate 2a, the thickness is preferably 0.8 mm or less.

  There is no limitation in particular in the screw member 3 used by this invention, A conventionally well-known thing can be used. For example, a machine screw, a washer built-in screw, a tapping screw, and the like can be given.

  From the viewpoint of easily generating elastic deformation of the inner portion of the thin plate 2a than the groove 22, as shown in FIG. 3, a plurality of through holes 23 are formed at predetermined intervals in the circumferential direction so as to divide the groove 22. It may be formed. The shape of the through hole 23 is not particularly limited. In addition to the circular through hole having a diameter larger than the width of the groove 22, a through hole having a diameter or width narrower than the width of the groove 22 may be formed on the bottom surface of the groove 22.

  4 and 5 show another embodiment of the thin plate fixing structure according to the present invention. 4 is a vertical sectional view when the thin plate 1 and the thin plate 2b are fixed by the screw member 3, and FIG. 5 is a perspective view.

  The thin plate fixing structure shown in these drawings is different from the above embodiment in that the thin plate 2b protrudes in a truncated cone shape on the side opposite to the contact surface with the thin plate 1, and a fastening hole 21 is formed at the center thereof. The second diaphragm portion 24 is provided. Since the thin plate 2b has such a second restricting portion 24 protruding outward, the volume of the space 4b formed between the thin plate 1 and the thin plate 2b is increased, and the screw member 3 is fastened to the thin plate 2b. The allowable bending amount of the thin plate 2b becomes large.

  As the amount of bending of the thin plate 2b increases, the elastic force for returning to the original also increases, and the fastening force between the screw member 3 and the thin plate 2b becomes stronger. Moreover, since the bending of the thin plate 2b is limited to the inner portion of the groove 22 as in the above embodiment, the flatness of other portions of the thin plate 2b is maintained. Further, the relative movement of the thin plate 1 and the thin plate 2b in the direction perpendicular to the axial direction of the screw member 3 is also suppressed. In this embodiment, the diameter of the second throttle section 24 is smaller than the diameter of the first throttle section 11, but the diameter of the second throttle section 24 is the same as or larger than the diameter of the first throttle section 11. It doesn't matter. However, in this case, even if the thin plate 2b is bent, it does not enter the first throttle portion 11, so that the relative movement between the thin plate 1 and the thin plate 2b in the direction perpendicular to the axial direction of the screw member 3 is It may not be sufficiently suppressed.

  6 and 7 show another embodiment of the thin plate fixing structure according to the present invention. 6 is a vertical sectional view when the thin plate 1 and the thin plate 2c are fixed by the screw member 3, and FIG. 7 is a perspective view.

  The thin plate fixing structure shown in these drawings is different from the embodiment shown in FIGS. 1 and 2 in that the thin plate 2c protrudes in a truncated cone shape on the contact surface side with the thin plate 1 and has a fastening hole 21 at the center thereof. Is formed, the depth of the third diaphragm 25 is shallower than the depth of the first diaphragm 11, and the diameter of the third diaphragm 25 is larger than the diameter of the first diaphragm 11. It is a small point. Thereby, when the thin plate 1 and the thin plate 2 c are overlapped, the third throttle portion 25 enters the inside of the first throttle portion 11. Thereby, when the thin plate 1 and the thin plate 2c are to move relatively in the direction perpendicular to the axial direction of the screw member 3, the third throttle portion 25 and the thin plate 1 entering the first throttle portion 11 are Since the contact is immediately strong, the relative movement between the thin plate 1 and the thin plate 2c is surely suppressed to a smaller one. Also in this embodiment, similarly to the two embodiments, the fastening force between the screw member 3 and the thin plate 2c is increased by the elastic force due to the bending deformation of the thin plate 2c. Further, since the bending of the thin plate 2c is limited to the inner portion of the groove 22, the flatness of other portions of the thin plate 2c is maintained.

  In all the embodiments described above, the thin plate 1 has the first throttle portion 11 projecting outward. However, the present invention is not limited to this. The thin plate 1 does not have the first throttle portion 11 and passes through the flat plate. Of course, the hole 12 may be formed. Further, the fastening hole 21 formed in the second thin plate may be one in which a female screw is threaded on the inner peripheral surface. For example, a female screw is formed when the screw member is fastened with a tapping screw. There may be.

  The fixing structure of the present invention is useful because the second thin plate is elastically deformed to return to the original state by bending, and the thin plates can be firmly fixed with a screw member without increasing the number of parts. .

1 Thin plate (first thin plate)
2a, 2b, 2c Thin plate (second thin plate)
3 Screw member 4a, 4b, 4c Space 11 First throttle part 12 Through hole 21 Fastening hole 22 Groove 23 Through hole 24 Second throttle part 25 Third throttle part 31 Shaft part

Claims (5)

The first thin plate in which the through hole is formed and the second thin plate in which the tightening hole is formed are overlapped so that the central axes of the through hole and the tightening hole substantially coincide with each other, and the screw member is A structure in which the thin plate is fixed with a screw member by screwing into the fastening hole of the second thin plate through the shaft portion,
A throttle portion protruding outward is formed in at least one of the first thin plate and the second thin plate so that a space is formed between the through hole of the first thin plate and the tightening hole of the second thin plate, and the tightening hole And a concentric groove formed in the second thin plate.   The thin plate fixing structure according to claim 1, wherein the first thin plate is provided with a frustoconical or columnar first throttle portion protruding outward, and the groove is formed outside the first throttle portion.   The first thin plate is provided with a frustoconical or columnar first diaphragm portion protruding outward, and the second thin plate is also provided with a frustoconical or columnar second diaphragm portion protruding outward, The thin plate fixing structure according to claim 1, wherein the diameter of the throttle portion is smaller than the diameter of the first throttle portion, and the groove is formed outside the first throttle portion.   The first thin plate is provided with a frustoconical or columnar first diaphragm portion protruding outward, and the second thin plate is provided with a frustoconical or columnar third diaphragm portion protruding inward, and a third diaphragm The depth of the part is made shallower than the depth of the first throttle part, the diameter of the third throttle part is made smaller than the diameter of the first throttle part, and the groove is formed outside the first throttle part. Item 2. A thin plate fixing structure according to Item 1.   The thin plate fixing structure according to any one of claims 1 to 4, wherein a plurality of through holes are formed at predetermined intervals in the circumferential direction so as to divide the groove.