JP2009144883A - Washer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a washer preventing corotation with a bolt or a nut by a simple structure. <P>SOLUTION: This washer 10 has a bearing surface contact surface 12 formed on one surface and brought into contact with the bearing surface of the bolt or the nut, and a fastened object contact surface 13 formed on the other surface and brought into contact with an fastened object. Recessed portions 14 are formed in the fastened object contact surface 13 in a mutually spaced manner, projecting portions 15 are formed around the recessed portions, and height of each projecting portion 15 from the fastened object contact surface 13 is set to 20-50 μm. The washer 10 is brought into contact with the fastened object at the projecting portions 15 in order to be prevented from being slid. Since the washer is brought into contact with the nut at the original natural surface of a steel plate and is easily slid in comparison with contact with the fastened object through an uneven portion, no corotation when the nut is rotated and fastened occurs. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a washer having an uneven surface on one side in order to prevent slippage with a fastener.

  A washer is used between a screw, a bolt, a nut, and the like and a fastener to prevent loosening and uniform fastening pressure. There are various types of washers, such as round and square flat washers, counter washers, spring washers, and toothed washers. For example, high strength plain washers are used together with high strength bolts and nuts for fastening and joining steel structures of buildings. In this application, it is necessary from the viewpoint of building reliability that the steel structure is securely joined.

  For secure joining, the fastener contact surface that contacts the steel structure of the washer is fixed so that it does not move due to friction when the nut is tightened, and the nut slides on the seat contact surface on the opposite side of the washer. Must be rotated and tightened.

  However, at the actual construction site, when the nut is tightened with a washer sandwiched between the steel structure and the nut, the nut and the washer stick together and slide together between the washer and the steel structure. Circumference may occur. If the joint rotation occurs, the steel structure cannot be fastened, so the bolts, nuts, and washers must be replaced and tightened again. Therefore, it took extra time for construction and the construction period was extended.

  In addition, a large noise was generated between the washer and the steel structure during the co-rotation, which deteriorated the on-site environment and caused a great inconvenience around the site due to the noise.

  In order to prevent the above-mentioned troublesome co-rotation, it is only necessary to increase the coefficient of friction between the washer and the fastener so that no slip occurs between the washer and the fastener. Conventionally, a washer called a shot washer whose surface has been roughened by shot blasting on the surface of the washer has been used for joining steel structures using high-strength bolts.

  However, when shot blasting is performed on both surfaces, the contact surface with the nut is also roughened, and the friction coefficient between the nut and the washer increases, and on the contrary, there is a mixture that rotates together. For this reason, a shot washer in which shot blasting is performed only on one side of the washer is also used. However, since it is difficult to perform shot blasting on only one side, the processing cost is high.

In order to solve such a problem, Patent Document 1 (Japanese Patent Laid-Open No. 2003-172332) describes a configuration in which unevenness is provided on both sides of a round flat washer on the outer peripheral side of the seating surface contact portion. With this configuration, the washer comes into contact with the fastening object at the uneven portion and thus does not slip, and the nut comes into contact with the flat portion of the seat surface, so that it becomes slippery. Therefore, co-rotation can be prevented.
JP 2003-172332 A

  However, in the case of the washer described in Patent Document 1, if the unevenness formed on the washer is too large, the biting between the convex part and the fastening object is worsened. Further, even when the nut is tightened, the convex portion is not crushed, and the contact area is only the convex portion. For this reason, there is a problem that the contact area becomes small and it becomes easy to loosen after tightening.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a washer that can prevent co-rotation with a simple structure and can prevent loosening after tightening. It is.

  In order to achieve the above object, the washer of the present invention comprises a flat plate having a bolt insertion hole in the center, has a seating surface contact surface that contacts a seating surface of a bolt or nut on one side, and is fastened on the opposite side. A washer having a fastener contact surface in contact with an object, wherein concave portions are provided on the fastener contact surface so as to be spaced apart from each other, and a convex portion is formed around the concave portion, and the fastener of the convex portion The height from the contact surface is 20 to 50 μm.

  The concave portion and the convex portions on both sides thereof are formed on the periphery of the fastener contact surface, or the washer formed with the concave portion has a concave shape at the center, and both ends of the fastener contact surface. It is configured to be curved so as to come into contact with the surface of the fastening object first from the portion or the peripheral portion, or the concave portion is formed by pushing a convex shape, and the convex portion pushes the convex shape When the concave portion is formed, the structure is a bulge that can be formed in the peripheral portion, or there is a convex portion on one side of each concave portion in the middle of the two adjacent concave portions, and between these convex portions and the convex portions. The structure may be such that the fastener contact surface that is not deformed remains, or the concave portion is a concave groove, and the convex portion is formed on both sides of the concave groove.

  Concave portions were formed on the fastener contact surface facing the fasteners of the washer so as to be separated from each other, and convex portions were formed on the peripheral edge of the concave portion. And the height of a convex part protrudes 20-50 micrometers from the fastener contact surface. When the nut is tightened, the plurality of convex portions are provided so that the washer is prevented from slipping against the fastener. Since there is no unevenness on the seating surface contact surface on the nut side of the washer, the friction coefficient between the nut and the seating surface contact surface is the natural friction coefficient of the original steel plate, and the fastener contact surface Is less than the friction coefficient. Therefore, it slides between the washer and the nut. For this reason, the nut and the washer can be securely tightened without causing co-rotation. As tightening progresses and the completion of fastening is near, a large force is applied to the convex part on the surface of the fastening object contact surface, and the crushed meat flows into the concave part. When the fastening is completed, almost the entire surface of the washer comes into contact with the fastener, so that the decrease in fastening pressure over time is small. That is, the looseness that occurs in the fastening portion over time is small, and it is possible to maintain a reliable fastening that prevents the loosening over the long term.

  The anti-slip unevenness may be provided on the entire surface of the fastener contact surface, but if it is provided only on the peripheral edge, a large resistance torque can be obtained when pressed against the fastener, preventing co-rotation. Great effect.

  When the washer in which the concave portion is formed is curved in a concave shape at the center, the fastener contact surface comes into contact with the fastener first from both ends in the case of a saddle type and from the peripheral portion in the case of a truncated cone type. Therefore, since the contact is started from the peripheral portion of the washer having a large resistance, a large resistance torque can be obtained, and the effect of preventing co-rotation is great.

  The concave portion is formed by pushing a convex shape, and when the convex portion is formed by pushing the convex shape to form a concave portion, the convex portion can be formed on both sides. Can be easily performed. Further, when the nut is tightened, the convex portion flows into the concave portion and can return to a substantially flat state.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1A is a central longitudinal sectional view of an embodiment of the washer of the present invention, and FIG. 1B is a view of a fastener contact surface (back surface) of the washer. This washer 10 is a flat washer with a circular outer periphery, and a bolt insertion hole 11 concentric with the outer peripheral circle is opened at the center. The upper side of FIG. 1A is a bearing surface contact surface 12 that contacts a seat surface of a bolt or nut, and the lower side is a fastener contact surface 13 that contacts a fastener. The seat surface contact surface 12 is a surface having no unevenness, but the fastener contact surface 13 is formed with unevenness on the entire surface. As shown in FIG.1 (b), the center of the fastener contact surface 13 of the washer 10 in which the recessed part 14 was formed is curving concavely. Therefore, it comes to contact a fastening object from both ends first.

  In FIG. 1 (b), the washer 10 is curved in a dish shape (conical frustum shape), but by doing so, it comes into pressure contact with the fastener from the outer peripheral edge, and at the initial stage of tightening, a larger detent Torque can be obtained. However, a flat surface may be used without giving a curve. Moreover, you may make it curve not in a dish shape but in a bowl shape. FIG. 1C shows an example of a washer 10 ′ in which irregularities are formed only on the peripheral edge of the fastener contact surface 13. Also in this case, it can be curved in a dish shape or a bowl shape.

  FIG. 2 is an enlarged view of a part of FIG. A plurality of concave portions 14 and convex portions 15 are formed on both sides of each concave portion 14 on the fastener contact surface 13. And between two adjacent recessed parts 14 and 14, there is a convex part 15 on one side of each concave part 14, and between these convex parts 15 and the convex parts 15, a fastener contact that is not subjected to deformation. Surface 13 remains. The concave portion 14 is formed by pressing a convex shape formed on the mold, and the convex portions 15 on both sides are formed on both sides when the concave portion 14 is formed by pressing. .

  In the present embodiment, the concave portion 14 and the convex portion 15 of the washer 10 are all formed parallel to the washer 10 in a certain direction. The concave portion 14 and the convex portion 15 shown in FIG. 2 have the same length.

  When the bolt or nut is tightened, it is the convex portion 15 that contributes to prevention of slippage with the fastener 20. By pressing the washer 10 against the fastening object, the convex part 15 forms a concave part on the surface of the fastening object and gets caught. Then, the fastener and the washer 10 are prevented from slipping. Since the convex part 15 protrudes from the fastening object contact surface 13 by 20 to 50 μm, it is preferable that the convex part 15 is caught on the surface of the fastening object or has a large friction. Although the space | interval of the recessed part 15 is not specifically limited, About 1-5 mm is practical.

  This is because, when the height h of the convex portion 15 is less than 20 μm, when the washer 10 is fastened to the fastening object with a nut or the like, the amount of the protrusion of the washer 10 that bites into the fastening portion is too small, and co-rotation tends to occur. On the other hand, if the thickness exceeds 50 μm, when the washer 10 is tightened, the convex portion 15 does not become flat and cannot be brought into contact with the entire fastener contact surface 13, so that the screw is liable to loosen.

  The concave portion 14 and the convex portion 15 are arranged only in the vicinity of the outer peripheral edge portion of the washer 10, and the washer itself is formed in a dish shape as shown in FIG. Thus, the convex portion 15 formed in the vicinity of the outer periphery can firmly bite into the fastening object. Further, since this biting position is on the outer peripheral side, a larger counter-rotating force is generated, which effectively works to prevent co-rotation.

  FIG. 3 is a view showing a method for manufacturing a washer according to the present invention. The washer 10 of the present invention is formed by punching a steel plate 100 between a punch 110 and a die 120. Bolt insertion holes 11 are drilled in the steel plate 100 in advance. The stamped washer 10 has a concave curve on the punch 110 side as shown in FIG.

  FIG. 4A is a diagram showing the next washer manufacturing process, where the washer 10 is straightened and chamfered. That is, the punched washer 10 is turned over and placed on the die 140, and the punch 130 is lowered from above to correct the curvature of the washer 10. At the same time, the chamfer 11 a of the inner peripheral end on the upper surface side of the bolt insertion hole 11 is performed by the inclined surface 131 at the tip of the punch 130. At this time, the concave and convex portions 141 and the convex portions 15 are formed on the entire surface or the outer peripheral edge of the fastening object contact surface 13 of the washer 10 by the concave and convex portions 141 provided in advance on the surface of the die 140.

  FIG. 4B is a cross-sectional view of the washer 10 thus formed and formed into a flat plate shape. Since the washer 10 can be greatly curved in the punching process of FIG. 5, the curvature remains even after the concave portion 14 and the convex portion 15 are formed in FIG. 4A, resulting in a dish shape having a depth of d. Alternatively, it is possible to form a curve by forming a punch that forms irregularities in a convex shape and a lower die in a dish shape.

  In addition, when the washer 10 becomes flat in the process of FIG. When such a washer 10 is manufactured, it is not particularly necessary to add a process, and the manufacturing cost is the same as that of a normal washer.

  FIG. 5 is a view showing a state where the nut is tightened. A through hole 22 through which the bolt 30 is inserted is opened in the fastening object 20, and the bolt 30 passes therethrough. Although not shown at the lower end of the bolt 30, there is a head for retaining. The washer 10 is inserted from the tip of the penetrated bolt 30, and the washer 10 is placed on the surface 21 of the fastener 20. A nut 40 is screwed onto the washer 10. A bulging portion 41 is provided on the inner side of the seat surface of the nut 40, and the tip thereof is in contact with the seat surface contact surface 12 of the washer 10.

  The contact portion of the washer 10 with the surface 21 of the fastening object 20 is a fastening object contact surface 13, where there are a recess 14 and a projection 15, and friction between the washer 10 and the fastening object 20 is large and slips. Absent. On the other hand, the nut 40 and the seating surface contact surface 12 are in contact with each other at the bulging portion 41 and are easy to slip. Therefore, when the nut 40 is rotated and tightened, the washer 10 is fixed to the surface 21 of the fastener 20 and does not rotate with the nut 40.

  FIG. 6 shows a state in which the nut 40 is turned and finished. When the fastening is completed, the convex portion 15 that is in pressure contact with the surface 21 of the fastening object 20 is crushed and enters the concave portion 14 to become a substantially flat surface 17. Then, the surface of the fastener 20 comes into contact with the entire fastener contact surface 13 to the entire surface 17. Therefore, even if relaxation occurs after the time has elapsed after fastening, the washer 10 and the fastening object 20 remain in contact with almost the entire fastening object contact surface 13 of the washer 10, and the looseness that occurs is small and the fastening state is maintained. It can be held securely.

  The embodiment described above is an exemplification, and the present invention is not limited to these examples. The material of the washer may be a steel plate or stainless steel, and any other material that is used for a known washer may be used. The treatment of the washer surface may be any treatment such as rust prevention treatment such as plating. Further, the method for manufacturing the washer is not limited to the press work, and may be forging or casting. The shape of the non-slip concave portion 14 is not limited to a groove shape or a dot shape, and is not particularly limited, for example, when pyramid-shaped irregularities are continuously arranged or in a regular shape. The concave portion 14 and the convex portion 15 may be provided continuously or discontinuously on the entire surface. Also, the concave and convex portions 14 and the convex portions 15 of the washer may be produced by forming irregularities on the mold of the washer manufacturing apparatus, and the irregularities may be produced simultaneously with the production of the washer. Good. Moreover, you may produce the recessed part 14 and the convex part 15 in the steel plate of a raw material previously. The manufacturing method of the concave portion or the convex portion is not limited to press working, and may be grinding or coating. However, it is desirable that when the bolt or nut is tightened, the convex portion is crushed to enter the concave portion and become almost flat.

  Since the concave portion 14 and the convex portion 15 are provided only on the side that comes into contact with the fastening object, the distinction between the front and back sides is clear, and there is no mistake in use.

  After tightening the bolts and nuts, the anti-slip convex part 15 enters the concave part 14 and becomes a substantially flat fastening object contact surface 13, so that the looseness due to the relaxation after the fastening is completed is small, and the looseness also occurs over time. It becomes difficult and the fastening reliability is high.

(A) is the center longitudinal cross-sectional view of the Example of the washer of this invention, (b) is a figure of the fastener contact surface (back surface) of a washer. It is the figure which expanded a part of Fig.1 (a). It is a figure which shows the manufacturing method of the washer of this invention. (A) is a figure which shows the bending process and chamfering process of a washer, (b) is a center longitudinal cross-sectional view of the completed washer. It is sectional drawing which shows the state before the fastening using the washer of this invention. It is sectional drawing which shows the state of the completion of fastening using the washer of this invention.

Explanation of symbols

10 Washer
11 Bolt insertion hole
12 Seating surface contact surface 13 Fastening object contact surface 14 Recessed portion (concave groove)
15 Convex 40 Nuts

Claims (6)

A washer comprising a flat plate with a bolt insertion hole in the center, having a seating surface contact surface in contact with the seating surface of the bolt or nut on one side, and a fastener contact surface in contact with the fastener on the opposite side, Concave portions are provided on the fastener contact surface so as to be spaced apart from each other, a convex portion is formed around the concave portion, and a height of the convex portion from the fastener contact surface is 20 to 50 μm. And a washer. The washer according to claim 1, wherein the concave portion and the convex portions on both sides thereof are formed on a peripheral edge portion of the fastening object contact surface. 2. The washer in which the concave portion is formed has a concave shape at the center, and is curved so as to come into contact with the surface of the fastener first from both ends or a peripheral portion of the fastener contact surface. Or the washer according to 2. The concave portion is formed by pressing a convex shape, and the convex portion is a bulge formed at a peripheral portion when the convex shape is pressed to form a concave portion. The washer according to any one of 3 above. There is a convex portion on one side of each concave portion between two adjacent concave portions, and a fastener contact surface that is not deformed remains between these convex portions. The washer according to any one of claims 1 to 4. The washer according to any one of claims 1 to 5, wherein the concave portion is a concave groove, and the convex portion is formed on both sides of the concave groove.

Images