JP2009063125A - Washer and water tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a washer capable of relaxing stress concentration to a fastened member at a fastening portion without increase of a weight or costs, and a water tank, in which a plurality of panels are fastened using this washer. <P>SOLUTION: A plane part 32A coming into face contact with a panel face 14P of a panel 14, an upright part 32B contacting two ribs 16 of the panel 14, respectively, and a boundary part 32C of the plane part 32A and the upright part 32B are formed on this washer 32. Each portion from the plane part 32A via the boundary part 32C to the upright part 32B comes into face contact with the panel face 14P of the panel 14, the boundary part 34, and the ribs 16. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a washer and a water tank, and more particularly to a washer applied to a fastening member for fastening a plurality of fastened members and a water tank using the washer.

  Washers are often used for fastening members such as bolts and nuts used when fastening a plurality of members to be fastened. For example, Patent Literature 1 describes a technique for improving the fatigue life of a bolt by forming a spherical washer from a pair of upper and lower washers having spherical surfaces that are in surface contact with each other.

  By the way, as a to-be-fastened member, there exists a thing in which the circumference | surroundings of a bolt insertion hole, etc. are curved-surface shape. When, for example, the washer of Patent Document 1 is applied to such a curved member to be fastened, stress is concentrated on the fastening portion when a large input acts on the fastening member itself or between the fastened members.

In order to prevent damage to the fastened member due to such stress concentration, for example, a reinforcing member may be provided in the vicinity of the fastening portion, but this causes an increase in weight and cost. Moreover, even if the washer is increased, the weight and cost are increased. In particular, considering a water tank in which a plurality of panels are fastened as a fastened member, it is desired to effectively relieve the stress concentration.
Japanese Utility Model Publication No. 6-53816

  In consideration of the above fact, the present invention includes a washer that can relieve stress concentration on a fastened member at a fastening portion without causing an increase in weight or cost, and a water tank that fastens a plurality of panels using the washer. The purpose is to obtain.

  According to the first aspect of the invention, the washer is applied to a fastening member that is inserted into the insertion hole of the member to be fastened and fastens the member to be fastened, and is used for a structure in which the member to be fastened is a curved surface around the insertion hole. And at least one part of the surface facing the said to-be-fastened member is made into the curved contact part so that a to-be-fastened member may surface-contact.

  That is, the fastened member has a curved surface around the insertion hole, but the washer of the present invention also has a curved contact portion so that at least a part of the surface facing the fastened member is in surface contact with the fastened member. Has been. Therefore, for example, even when a load is applied in the axial direction of the fastening member or when a moment is generated in the fastened member with the fastening portion as a fulcrum, the local load acting on the fastened member from the washer is reduced. And stress concentration can be reduced. A member that reinforces the member to be fastened is unnecessary, and it is not necessary to increase the washer, so that no increase in weight or cost is caused.

  The invention according to claim 2 is the washer according to claim 1, which is used for fastening the fastened member in which a rib is formed in the vicinity of the insertion hole in the invention according to claim 1.

  The curved contact portion of the washer has a shape that also contacts the rib.

  In this way, by making the curved contact portion of the washer into a shape that also contacts the rib, compared to a washer having a shape that does not contact the rib, it is more effective to act on the member to be fastened from the washer. Can reduce the load. Further, the strength of the fastened member is also increased by the rib.

  In the present invention, the specific shape of the washer is not particularly limited. For example, as in claim 3, the washer is formed in a circular shape, and the curved contact portion is formed over the entire circumference. Or the washer according to claim 1 or claim 2, wherein the curved contact portion is formed on at least two sides. Can do. In any shape, the local load acting on the fastened member from the washer can be effectively reduced.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the fastening member is a bolt and a nut, and is arranged between the bolt or nut and the fastened member. It is characterized by being.

  By using a bolt and a nut as the fastening member, the fastened member can be firmly fastened.

  When the nut is tightened into the bolt, a large tightening load acts on the fastened member in the axial direction of the bolt. Even in such a case, since the local load acting on the member to be fastened from the washer can be relaxed, the stress concentration can also be relaxed.

  The invention according to claim 6 is a water tank configured by joining a plurality of panels having ribs formed around them, an insertion hole formed in the panel in the vicinity of the rib or the rib, and an insertion hole A fastening member that is inserted into the panel and fastens the panels or another member to the panel, and a washer according to any one of claims 1 to 5 that is used for the fastening member and is in surface contact with the panel. It is characterized by having.

  In the present invention, a plurality of panels are joined to form a water tank. However, when the fastening member is inserted into an insertion hole formed in the panel, the panels or the panel and another member are fastened. The washer according to any one of claims 1 to 5 is used for the fastening member, and is in surface contact with the panel. Therefore, for example, even when a load is applied in the axial direction of the fastening member or when a moment is generated in the panel with the fastening portion as a fulcrum, the local load acting on the panel from the washer can be reduced, and the stress can be reduced. Concentration can also be eased. A member that reinforces the panel is unnecessary, and it is not necessary to increase the washer, so there is no increase in weight or cost.

  Since this invention was set as the said structure, the stress concentration to the to-be-fastened member in a fastening part can be relieve | moderated, without causing a weight increase and cost increase.

  The whole structure of the water tank 12 which concerns on 1st embodiment of this invention is shown by FIG. Further, in FIG. 2, in this water tank 12, a support column 20 (details will be described later) to which the washer 32 of the first embodiment is applied is partially enlarged. Further, FIG. 3 shows an enlarged fastening portion to which the washer 32 is applied.

  As can be seen from FIG. 1, the water tank 12 is configured by joining a plurality of panels 14 made of resin (for example, FRP). Each of the panels 14 is formed in a quadrangular shape, and ribs 16 rising at right angles from the substantially flat panel surface 14P are formed so as to continue around the panel surface 14P. Has been enhanced. In the rib 16 or the panel surface 14P in the vicinity of the rib 16, bonding bolt holes are formed at regular intervals, and the bonding bolts 17 are formed in a state in which the bonding bolt holes are aligned with each other between the adjacent panels 14. The panels 14 are joined by being inserted and further tightened with the joining nut 19.

  As shown in FIG. 2, a support column 20 is erected in the water tank 12 and fixed to the upper surface and the lower surface of the water tank 12, and in particular, the corners of the panel 14 are reinforced so that the entire water tank 12 can be reinforced. As the strength is increased. In particular, a plurality of (two in the present embodiment) fastening brackets 22 are disposed at the lower end of the support column 20, and the fastening bracket 22 is fastened to the surface facing the panel 14 as shown in FIG. A bolt hole 24 is formed.

  On the other hand, a fastening bolt hole 26 is also formed in the vicinity of the rib 16 on the panel surface 14 </ b> P of the panel 14 constituting the lower surface of the water tank 12. With the fastening bolt hole 24 of the fastening bracket 22 and the fastening bolt hole 26 of the panel 14 aligned, as shown in FIG. 3, a fastening bolt 28 is inserted from the water tank 12, and further for fastening. The column 20 is fixed to the panel 14 by tightening the nut 30 into the fastening bolt 28 from outside the water tank 12. In the present embodiment, the fastening bolt 28 and the fastening nut 30 constitute the fastening member of the present invention.

  A washer 32 is disposed between the fastening nut 30 and the panel 14. The washer 32 of the present embodiment is composed of a single sheet metal and is formed in a substantially triangular shape when viewed from below (in the axial direction of the fastening bolt 28). And it has the plane part 32A which surface-contacts with the panel surface 14P of the panel 14. As shown in FIG. From the flat surface portion 32A, a standing portion 32B is formed so as to be in contact with each of the two orthogonal ribs 16, and a boundary portion 32C between the flat surface portion 32A and the standing portion 32B is formed on the panel surface 14P. And a curved surface shape (having a rounded shape) along the boundary portion 34 of the rib 16. Accordingly, the washer 32 is a curved contact portion according to the present invention as a whole, that is, each portion from the flat portion 32A through the boundary portion 32C to the standing portion 32B, that is, the surface facing the panel 14 as a whole. The panel surface 14 </ b> P, the boundary portion 34, and the rib 16 are in surface contact.

  Next, the operation of this embodiment will be described.

  In the water tank 12 of the present embodiment, the lower end (fastening fitting 22) of the support column 20 is fastened to the panel 14 by fastening bolts 28 and fastening nuts 30 as shown in FIG.

  Here, the washer 32 disposed between the fastening nut 30 and the panel 14 is in surface contact with the panel surface 14P and the rib 16 of the panel 14 by the plane portion 32A, the boundary portion 32C, and the standing portion 32B. . Since the contact area between the washer 32 and the panel 14 is large, for example, when a large load is applied in the axial direction of the fastening bolt 28 due to an earthquake or the like, or when the column 20 is inclined with respect to the panel 14 and a large moment is applied to the fastening portion. Even when the above acts, the local load acting on the panel 14 from the washer 32 can be reduced. Further, as indicated by an arrow F1 in FIG. 4, the load acting in the axial direction of the fastening bolt 28 is also distributed radially. As a result, the local stress concentration of the panel 14 can be reduced, so that the destruction of the panel 14 can be more effectively suppressed.

  In particular, in the configuration in which the bolt and the nut are used as the fastening members, such as the fastening bolt 28 and the fastening nut 30 according to the present embodiment, when the nut is tightened into the bolt, the fastening is performed in the axial direction of the bolt. A large tightening load acts on the panel 14 as a member. Even in such a case, since the local load acting on the panel 14 from the washer 32 can be relaxed, the stress concentration can also be relaxed.

  In addition, a sharp portion such as an edge does not exist in the portion of the washer 32 facing the panel 14. Also in this respect, the local load on the panel 14 can be relaxed, and the transverse shear fracture strength of the panel 14 is improved.

  In addition, in this embodiment, it is not necessary to use a reinforcing member in order to relieve local stress concentration of the panel 14. Therefore, the destruction of the panel 14 can be effectively suppressed without causing an increase in weight or cost. Since the labor of attaching the reinforcing member can be omitted, the workability is also improved. In addition, in order to prevent the panel 14 from being destroyed, for example, it is not necessary to increase the thickness of the panel 14 or provide a reinforcing layer therein, so that an increase in cost can also be suppressed in this respect.

  In order to alleviate the stress concentration on the panel 14 as described above, a configuration in which the washer is simply enlarged to ensure a wide contact area with the panel 14 is also conceivable. However, even if the washer is enlarged, for example, when a moment is applied to the fastening portion as described above, a load is applied to the panel 14 from the peripheral portion of the washer (if reduced, the position where the load acts is for fastening) Therefore, the effect of suppressing the destruction of the panel 14 is small. In addition, increasing the size of the washer may increase the weight layer and cost. In this embodiment, even when compared with the configuration in which the washer is increased in size as described above, the stress concentration on the panel 14 can be effectively suppressed and the destruction thereof can be prevented without causing an increase in weight and cost.

  Further, in the washer 32 of the present embodiment, it is effective to provide the boundary portion 32C and the standing portion 32B only on one side of the triangular (or polygonal) plane portion, but the curved surface corresponding to two or more sides. It is preferable to provide a shape-like portion (the boundary portion 32C and the standing portion 32B) because it becomes a fulcrum at the moment of action and does not perform so-called “one-sided contact”.

  The specific shape of the washer 32 is determined in accordance with the shape of the member to be fastened (the panel 14 in the above embodiment), and includes various shapes as shown in the following embodiments.

  FIG. 5 shows a washer 52 according to the second embodiment. In the second embodiment, a member to be fastened according to the present invention is assumed to be softer (here, two pieces of wood 54A, 54B) than the panel (made of resin) of the first embodiment.

  In the wood 54 </ b> A, a circular recess 56 is formed around the fastening bolt hole 24 when viewed in the axial direction of the fastening bolt 28. The concave portion 56 includes a flat portion 56A in the center (near the fastening bolt hole) and a curved portion 56B that continues from the flat portion 56A to the outer edge.

  The washer 52 of the second embodiment corresponds to the recess 56 and is circular when viewed in the axial direction of the fastening bolt 28. A flat surface portion 52A that is in surface contact with the flat surface portion 56A of the concave portion 56 and a curved portion 52B that is continuous from the flat surface portion 52A and contacts the curved portion 56B of the concave portion 56 are formed over the entire circumference. The portion from the flat portion 52A to the curved portion 52B is the curved contact portion of the present invention as a whole.

  Also in the washer 52 of the second embodiment having such a configuration, when a large load is applied in the axial direction of the fastening bolt 28, or when the fastening bolt 28 is inclined with respect to the wood 54A, a large moment is applied to the fastening portion. Even if it acts, the local load acting on the wood 54A from the washer 52 can be reduced.

  In the washer 32 of the first embodiment, the boundary portion 32C and the standing portion 32B continuous from the flat surface portion 32A are formed by bending the edge portion of the flat plate. On the other hand, in the washer 52 of the second embodiment, the curved portion 52B continuous from the flat portion 56A is formed by gradually reducing the thickness of the flat plate in the vicinity of the edge portion. As described above, as the washer of the present invention, it is sufficient that at least a part of the surface facing the curved portion of the fastened member is in surface contact, and the specific processing method and shape of the washer are particularly limited. Not.

  FIG. 6 shows a washer 62 according to a third embodiment of the present invention. In 3rd embodiment, the two resin members 64A and 64B arrange | positioned, for example inside a household appliance are assumed as a to-be-fastened member which concerns on this invention.

  On one resin member 64A, a rib 66 is formed around the fastening bolt hole 24, and a rectangular recess 68 is formed inside the resin member 64A as viewed in the axial direction of the fastening bolt 28. As in the second embodiment, the concave portion 68 includes a flat portion 68A and a curved portion 68B that continues from the flat portion 68A to the outer edge.

  The washer 62 of the third embodiment has a rectangular shape when viewed in the axial direction of the fastening bolt 28 corresponding to the recess 68. A flat surface portion 62A that is in surface contact with the flat surface portion 68A of the concave portion 68 and a curved portion 62B that is continuous from the flat surface portion 62A and that contacts the curved portion 68B of the concave portion 68 are formed. A portion from the flat portion 62A to the curved portion 62B is a curved contact portion of the present invention as a whole. Further, a female screw 70 is formed in the fastening bolt hole 28 of the washer 62, and has a function as a nut (a backup function for the fastening bolt).

  Also in the washer 62 of the third embodiment having such a configuration, when a large load is applied in the axial direction of the fastening bolt 28, or when the fastening bolt 28 is inclined with respect to the resin member 64A, a large moment is applied to the fastening portion. Even when the above acts, the local load acting on the resin member 64A from the washer 62 can be reduced.

  FIG. 7 shows a washer 72 according to a fourth embodiment of the present invention. In the fourth embodiment, for example, a cover member 74 that covers wiring or the like and a wall surface (not shown) to which the cover member 74 is attached are assumed as the fastened members according to the present invention.

  That is, the cover member 74 is formed by bending a thin plate of metal or resin at a predetermined position, and a vertical portion 74B that rises substantially vertically from both sides of the flat portion 74A where the fastening bolt holes are formed via the boundary portion 74C. Has a substantially U-shaped cross section. Inside the cover member 74, wiring, piping, or a supporting member that supports them is disposed.

  The washer 72 of the fourth embodiment has a quadrangular shape when viewed in the axial direction of the fastening bolt 28, and is continuous from the flat surface portion 72A that is in surface contact with the flat surface portion 74A of the cover member 74, and the flat surface portion 72A. A curved portion 72B and a vertical portion 72C are formed in contact with the boundary portion 74C and the vertical portion 74B, respectively. From the flat surface portion 72A through the curved portion 72B to the vertical portion 72C as a whole is the curved contact portion of the present invention.

  Also in the washer 72 of the fourth embodiment having such a configuration, when a large load is applied in the axial direction of the fastening bolt 28, or when the fastening bolt 28 is inclined with respect to the cover member 74, a large moment is applied to the fastening portion. Even if the above acts, the local load acting on the cover member 74 from the washer 72 can be reduced.

  As described above, the member to be fastened according to the present invention is not particularly limited, and the washer can be made of an appropriate material and shape in relation to the material and shape of the member to be fastened. For example, you may use the washer of this invention for the structure which connects the panels 14 as a to-be-fastened member. The fastening members are not limited to bolts and nuts, and may be nails or rivets.

  Further, the washer of the present invention does not need to be in surface contact with the member to be fastened over the entire surface facing the member to be fastened. For example, in the washer 82 of the fifth embodiment shown in FIG. 8, the structure from the flat portion 82A through the boundary portion 82C to the standing portion 82B is the same as that of the washer 32 of the first embodiment, but outside the boundary portion 82A. Is chamfered obliquely, and a gap SP is generated between the panel 14 (a member to be fastened). However, since the entire facing surface of the washer 82 is in surface contact with the panel 14, the same effect as the washer 32 of the first embodiment can be obtained.

  Of course, as in the first embodiment to the fourth embodiment, it is preferable that the washer of the present invention is in contact with the rib or recess formed in the fastened member along its shape.

  The present invention will be described in more detail with reference to examples. Of course, the present invention is not limited to the following examples.

[Examples 1 to 3]
In Examples 1 to 3, the washer 32 of the first embodiment was applied to the water tank 12 of the first embodiment. The structure of the washer 32 was as follows.

<Configuration of washer 32>
Material: Iron (may be stainless steel)
Size of the flat portion 32A (long side × short side × thickness): 60 mm × 60 mm × 4.5 mm
Standing height of standing part 32B: 10 mm
The washer 32 substantially has an isosceles triangle shape.

[Comparative Examples 1-3]
In Comparative Examples 1 to 3, a circular washer 102 was used as shown in FIG. 9 instead of the washer 32 of the example. This washer 102 has a larger diameter than that generally assumed to be used when the support column 20 is fixed to the water tank 12.

<Configuration of washer 102>
Material: Iron (may be stainless steel)
Size (diameter x thickness): 30mm x 3mm

[Comparative Example 4]
In Comparative Example 4, as shown in FIG. 10, a washer 102 was used, and a fastening bolt 104 having a length longer than that of the example was used, and a long nut 106 was screwed into this. Further, the reinforcing member 108 was disposed outside the water tank 12 and attached to the panel 14 using the mounting bolts 110 and the long nuts 106. The shape of the reinforcing member 108 and the dimensions of each part are also shown in FIG.

<Configuration of long nut 106>
Material: Iron (may be stainless steel)
Size (nominal x length): M12 x 40mm

<Configuration of reinforcing member 108>
Material: Steel Shape: H-shaped steel (see Fig. 11)
Size: (Height x Width x Thickness): 198mm x 99mm x 4.5mm or 7mm
Position of insertion hole through which the mounting bolt is inserted: 7mm thick part

なお、評価にあたっては、２４．１９ｋＮ（２４６８ｋｇｆ）の荷重を判定の閾値とし、これ以上の荷重を作用させても、パネル１４に本質的な破壊が生じない（たとえば表面のクラック程度であれば問題ない）ものを「◎」、パネル１４に破壊が生じるものを「△」、さらに締結用ボルトにも破壊が及ぶものを「×」とした。 <Test method and evaluation>
The structure using the washer of each example and each comparative example was subjected to a tensile test at a tensile speed of 1 mm / min using an autograph tester, and the breaking load of the panel 14 was measured. The results are shown in Table 1.

In the evaluation, a load of 24.19 kN (2468 kgf) is set as a threshold for determination, and even if a load higher than this is applied, the panel 14 is not essentially destroyed (for example, if it is about a crack on the surface) No)), "△" indicates that the panel 14 is broken, and "x" indicates that the fastening bolt is broken.

  As can be seen from Table 1, in the configurations of Comparative Examples 1 to 3 using the large washer 102, the bottom surface of the panel 14 is damaged. Further, in the configuration of Comparative Example 4 in which the long nut 106 is used together with the washer 102 and the reinforcing member 108 is attached, the panel 14 or the like is not damaged. However, since the washer 102 and the long nut 106 are used and the reinforcing member 108 is further attached, the workability is poor and the weight is increased.

  In contrast, in the configurations of Examples 1 to 3, the panel 14 is not damaged. Moreover, since it is not necessary to use the washer 102 or the long nut 106 or to attach the reinforcing member 108, the workability is good and the weight is not increased.

It is a perspective view which shows schematic structure of the water tank to which the washer of 1st embodiment of this invention was applied. It is a perspective view which expands and shows the lower end of the support | pillar of the water tank which concerns on 1st embodiment of this invention, and its vicinity. It is a perspective view which shows the fastening structure using the washer concerning 1st embodiment of this invention in the state seen from the lower side of the water tank. It is a cross-sectional view which shows the fastening structure using the washer which concerns on 1st embodiment of this invention. It is a cross-sectional view showing a fastening structure using a washer according to a second embodiment of the present invention. It is a perspective view which shows the fastening structure using the washer which concerns on 3rd embodiment of this invention. It is a perspective view which shows the fastening structure using the washer which concerns on 4th embodiment of this invention. It is a cross-sectional view showing a fastening structure using a washer according to a fifth embodiment of the present invention. It is a perspective view which shows the fastening structure using the washer of the comparative example in the state seen from the lower side of the water tank. It is a perspective view which shows the fastening structure using the washer of the comparative example different from what was shown in FIG. 9 in the state seen from the lower side of the water tank. It is the schematic which shows the shape and dimension of the reinforcement member which concerns on the comparative example 4.

Explanation of symbols

12 Water tank 14 Panel (fastened member)
14P Panel surface 16 Rib 18 Joining bolt hole 20 Strut 22 Fastening fitting (fastened member)
24 Fastening bolt holes (insertion holes)
26 Fastening bolt holes (insertion holes)
28 Fastening bolt (fastening member)
30 Nut for fastening (fastening member)
32 Washer 32A Plane part (curved contact part)
32B Standing part (curved contact part)
32C boundary part (curved surface contact part)
52 Washer 52A Plane part (curved contact part)
52B Curved part (curved contact part)
54A, 54B Wood (fastened member)
62 Washer 62A Plane part (curved surface contact part)
62B Curved part (curved contact part)
64A, 64B Resin member (fastened member)
72 Washer 72A Plane part (curved contact part)
72B Curved part (curved contact part)
72C Vertical part (curved contact part)
82 Washer

Claims (6)

A washer that is applied to a fastening member that is inserted into an insertion hole of a member to be fastened and fastens the member to be fastened, and that is used in a structure in which the member to be fastened is curved around the insertion hole,
A washer characterized in that a curved contact portion is formed so that at least a part of a surface facing the fastened member comes into surface contact with the fastened member. The washer according to claim 1, wherein the washer is used for fastening the fastened member in which a rib is formed in the vicinity of the insertion hole,
The washer characterized in that the curved contact portion of the washer is also in contact with the rib. A washer according to claim 1 or claim 2 formed in a circular shape,
A washer characterized in that the curved contact portion is formed over the entire circumference. A washer according to claim 1 or claim 2 formed into a polygon,
The washer characterized in that the curved contact portion is formed on at least two sides. The fastening member is a bolt and a nut;
The washer according to any one of claims 1 to 4, wherein the washer is arranged between the bolt or nut and the member to be fastened. A water tank constructed by joining a plurality of panels formed with ribs around,
An insertion hole formed in the panel near the rib or the rib;
Fastening members that are inserted into the insertion holes and fasten the panels or the panel and other members;
The washer according to any one of claims 1 to 5, wherein the washer is used for the fastening member and is in surface contact with the panel.
A water tank characterized by having.

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