JP2006194291A - Locking washer, failure detection device for oil lifter and fastening method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To fasten a member by stable and appropriate fastening force without being influenced on machining accuracy of a male screw through hole of the fastening member and provide a fixing device. <P>SOLUTION: A locking washer is formed at a insertion opening of a bolt 15. An outside side surface shape is tapered toward a male screw insertion side. A taper inclined surface 23 having roughly same inclination as an inclination of a tapered surface of a projection 12 of a nut 10 is formed on a nut side end edge part of a bolt through-hole 21 having a bolt 15 pass through and arranged in the projection 12 side deformed by external force and fastening a male screw. Also, a plurality of kinds of the locking washers 20 provided with different shapes and forming different interferences are prepared and the locking washer 20 of a selected shape is used according to interference dimension of a fastening structure. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a washer, and in particular, is provided with a tapered surface that is screwed into a male screw and formed on the male screw insertion side, and has a tapered outer surface formed on the male screw insertion side. The present invention relates to a loose washer used together with a nut having a protrusion for tightening.

  When tightening bolts and nuts, a flat washer or a spring washer is usually placed on the back of the bolt or nut. Since the flat washer has a thin ring shape, if bolts and nuts are tightened strongly, they may spin idle, and are not always sufficiently tightenable. The spring washer has a part of the ring divided and its end is opened to the outside in the thickness direction, so it will not run idle like a flat washer even if the bolt or nut is tightened strongly, and the spring characteristics are also Therefore, tightening is more reliable than flat washers. However, in either case, the bolts and nuts may loosen due to vibration after tightening, and this cannot be avoided. In addition, a so-called double nut fastening in which the nuts are overlapped is also used, but two nuts are required and the fastening portion height dimension is increased.

  In order to solve such problems, various washer and the like have been proposed. In Patent Document 1, there are a plurality of protrusions on both the front and back surfaces or one surface of a spring washer, the protrusion on one surface is a meshing protrusion that can be engaged with a locking protrusion of screws, and the protrusion on the other surface is a screw. It was set as the biting protrusion which can bite into the clamp | tightening target object clamp | tightened with the kind. The screws with a locking mechanism are provided with a flat washer with a protrusion on the back side of the screw or a recess that can accommodate a spring washer. A locking projection was provided in the recess. The locking projection in the recess has a climbing ramp that can be rotated over the tightening ramp of the mating projection of the flat washer or spring washer with the projection in the recess, and is locked to the regulating surface of the mating projection on the opposite side of the ramp A loosening restricting portion for restricting rotation of the screws in the loosening direction is provided, and a loosening prevention protrusion is provided on the back surface of the outer peripheral wall of the recess. A spring washer is incorporated on the back of the bolt and nut.

  There is also a nut with a locking function. 3 and 4, the nut 10 is formed on the male screw insertion side of the seat surface 11 of the nut 10, and the protrusion 12 having a tapered surface whose outer side surface shape is tapered toward the male screw insertion side is screwed. These are provided at three positions around the hole 14 every 120 °. The protrusion 12 is deformed by a force from the outside, tightens the male screw, and acts to prevent loosening. In this example, the slope α of the slope of the protrusion 12 with respect to the seating surface 11 is about 45 °.

  In order to form a fastening structure using such a nut 10, as shown in FIG. 10, male screw portions 15 a of bolts 15 are inserted into through holes 16 a, 17 a of members to be fastened 16, 17 through washers 18. The nut 15 is screwed onto the bolt 15. In such a case, a washer is usually not disposed between the nut 10 and the member 16 in many cases.

When the nut 10 is tightened in this state, a gap S (tightening allowance) is generated between the member 16 and the seat surface 11 when the protrusion 12 comes into contact with the peripheral edge portion 16b of the through hole 16a. Further, the nut 10 is tightened until the gap S disappears, and the protrusion 12 is pressed inwardly by the peripheral edge portion 16b of the through hole 16a to tighten the male screw portion 15a, thereby preventing the loosening.
JP 2002-031120 A

  By the way, when the nut 10 having the locking function is used, the tightening force is determined by the dimension of the gap S. The size of the gap S is determined by the size of the peripheral edge portion 16 b of the member 16. Normally, such a through hole 16a is not high in dimensional accuracy, as referred to as a “fool hole”. Therefore, a constant tightening force cannot be obtained unless the processing accuracy of the peripheral edge portion 16b is good.

  For this reason, in order to use the said nut effectively, there exists a problem that the hole diameter of a through-hole of a fastening member and the process of a peripheral part must be finished and managed accurately, and cost will increase.

  In addition, when replacing a bolt and nut that has already been used with a new one, it is necessary to check whether the already opened hole is appropriate. Furthermore, when this nut is used, the hole periphery is deformed, and the bolt and nut is deformed by rust or the like, and an appropriate tightening force may not be obtained.

  Therefore, the present invention provides a washer and a fastening structure that can fasten a member with a stable and accurate fastening force without being affected by the processing accuracy of the male screw through hole of the fastening member, and that can prevent loosening. And

  According to the first aspect of the present invention, in the loose washer, the outer side surface is formed to project from the side surface where the male screw is inserted and is tapered in the male screw insertion direction, and the male screw is tightened by being deformed by a force from the outside. A loose washer used together with a nut provided with a protrusion, formed on the protrusion side surface of the nut, and substantially inclined to the tapered surface of the nut protrusion on the nut side edge of the through hole through which the male screw passes. This is a loose washer having a tapered inclined surface with an equal inclination.

  The invention of claim 2 is the loose washer of claim 1, wherein the opening angle of the tapered inclined surface of the washer is larger than the opening angle of the tapered surface of the washer.

  The invention of claim 3 is characterized in that, in the loose washer of claim 1 or 2, the projection of the nut is formed by being divided into a plurality of circumferential portions desired for the opening of the female screw portion of the nut. To do.

  According to a fourth aspect of the present invention, in the loose washer according to the first to third aspects, the projection of the nut is formed with a threaded portion that is screwed into the male thread continuously with the female threaded portion of the nut. .

  The invention of claim 5 includes a male screw, a tapered surface formed on the male screw insertion side and having a tapered outer surface formed on the male screw insertion side, and is deformed by a force from the outside to tighten the male screw. A fastening structure using a nut and the loose washer according to any one of claims 1 to 4.

  According to a sixth aspect of the present invention, in the fastening structure of the fifth aspect, a loose washer having a shape that changes a tightening allowance dimension of the nut according to the size of the tightening dimension is used.

  The invention of claim 7 is characterized in that, in the fastening structure of claim 6, the change of the tightening allowance is realized by changing the diameter of the opening on the small side formed by the tapered inclined surface of the loose washer. To do.

  The invention of claim 8 is characterized in that, in the fastening structure of claim 6, the change of the fastening allowance is realized by changing the thickness of the loose washer.

  The invention of claim 9 prepares a plurality of types of loose washers having different shapes and forming different fastening allowances, and uses the loose washers having a shape selected according to the fastening allowance dimensions of the fastening structure. It is the fastening method characterized by this.

  According to the present invention, the member can be tightened with a stable and accurate fastening force without being affected by the processing accuracy of the male screw through-hole of the fastening member, and the locking can be provided. Fastening force and locking effect can be obtained. Further, the nut can be easily fastened with a fastening allowance suitable for the fastening allowance dimension.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing a loose washer according to an embodiment of the present invention, and FIG. 2 is a sectional view of the loose washer shown in FIG.

  The loose washer 20 according to this example includes an annular main body 22 having a thickness d in which a bolt through hole 21 is formed in the center. In this example, the diameter D of the loose washer 20 is larger than the outer diameter of the nut 10 and is substantially equal to the outer diameter of the JIS washer.

  Further, in this example, a tapered inclined surface 23 is formed in the bolt through hole 21. The inclination β of the tapered inclined surface is slightly larger than the inclination α of the nut 10. For example, when the inclination α of the nut is 40 ° ± 1 °, the inclination β of the loose washer 20 is desirably about 41 ° ± 1 °.

  Next, a fastening structure using the loose washer 20 according to this embodiment will be described. FIG. 5 is a diagram illustrating a nut tightening start state in the fastening structure according to the embodiment, and FIG. 6 is a diagram illustrating a nut tightening end state in the fastening structure according to the embodiment. In this example, the nut 10 is started to be tightened, and a gap is opened by 1 between the nut 10 and the loose washer 20 in a state where the taper inclined surface 23 is first in contact with the taper inclined surface 23 of the loose washer 20. When the nut is tightened with this clearance as a tightening allowance, as shown in FIG. 6, the bolt 15 is extended in an elastic range, and an axial fastening force is generated.

  In such a fastening structure, when the optimum fastening allowance for the fastening length L is 1, an appropriate fastening force cannot be obtained unless the dimension of l is proportional to L. For example, if the dimension of L is halved, the tightening allowance must be halved. Similarly, if the dimension of L is doubled, l needs to be also doubled.

  Accordingly, it is necessary to prepare a plurality of types of the loose washer of the present invention by defining a range for each tightening length L in advance. That is, even when the same nut 10 is used, if the tightening dimension L is different, it is necessary to use a different locking washer.

  7 is a view showing a loose washer with a small tightening allowance, FIG. 8 is a view showing a loose washer with a large loose allowance, and FIG. 9 shows a state in which the tightening allowance is changed by the thickness of the loose washer. FIG.

  As shown in FIGS. 7 and 8, in the case of the loose washers 201 and 202 where the opening size of the tapered inclined surface 23 is different from φ1 and φ2 (φ1> φ2), the dimensions of the tightening allowance are s1, s2 (s1 < s2), it is necessary to use the loose washer 202 when the tightening length L is large, and the loose washer 201 when the tightening length L is small.

  Also, due to the difference in tightening dimension L, even if the loose washers having the same taper inclined surface 23 opening dimensions are set to d1, d2 (d1 <d2) as shown in FIG. Also, the tightening allowance can be s3, s4 (s3> s4).

  In this example, by preparing multiple types of loose washers having different shapes and forming different fastening allowances, by using the loose washers of the shape selected according to the fastening allowance dimensions of the fastening structure, By using an appropriate loose washer that fits different tightening allowance dimensions, an appropriate tightening force can be obtained. At this time, when using a loose washer with a tapered tapered surface that has been accurately calculated and processed with respect to the taper of the nut protrusion, an appropriate tightening force is generated when the nut is tightened to contact the loose washer. Therefore, the nut tightening torque can be easily adjusted.

It is a top view of the loose washer which concerns on embodiment. It is sectional drawing of the loose washer which concerns on embodiment. It is a front view of the nut used for the fastening structure concerning an embodiment. It is a bottom view of the nut used for the fastening structure concerning an embodiment. It is sectional drawing which shows the state of the fastening start of the nut in the fastening structure which concerns on embodiment. It is sectional drawing which shows the state of the fastening end of the nut in the fastening structure which concerns on embodiment. It is sectional drawing which shows the loose washer used for the fastening structure which concerns on embodiment. It is sectional drawing which shows the loose washer used for the fastening structure which concerns on embodiment. It is sectional drawing which shows the loose washer used for the fastening structure which concerns on embodiment. It is sectional drawing which shows the conventional fastening structure

Explanation of symbols

10 Nut 11 Seat surface 12 Projection 14 Hole 15 Bolt 15a Male thread portion 16, 17 Fastened member members 16a, 17a Through hole 16b Peripheral portion 18 Washer 20 Loose washer 21 Bolt through hole 22 Main body 23 Taper inclined surface 201, 202 Loose Washer

Claims (9)

A loose washer that protrudes from the male screw insertion side, has a tapered side surface that is tapered in the male screw insertion direction, and is used with a nut that has a projection that deforms by external force and tightens the male screw. Because
A taper inclined surface having a slope substantially equal to the slope of the taper surface of the nut protrusion is formed on the nut side edge of the through hole through which the male screw passes, formed on the protrusion side surface of the nut. Washer. The loose washer according to claim 1, wherein an opening angle of the tapered inclined surface of the washer is larger than an opening angle of the tapered surface of the washer. 3. The loose washer according to claim 1 or 2, wherein the projection of the nut is divided into a plurality of circumferential portions desired for opening of the female screw portion of the nut. 4. The loose washer according to claim 1, wherein the nut protrusion is formed with a threaded portion that is threaded onto the male screw continuously from the female threaded portion of the nut. A nut having a male screw, a taper surface formed on the male screw insertion side and having a tapered outer surface formed on the male screw insertion side, and having a projection that is deformed by an external force to tighten the male screw. A fastening structure characterized by using any one of the loose washers. 6. The fastening structure according to claim 5, wherein a loose washer having a shape for changing a tightening allowance dimension of the nut in accordance with a tightening dimension is used. The fastening structure according to claim 6, wherein the change of the tightening allowance is realized by changing a diameter of an opening on a small side formed by the tapered inclined surface of the loose washer. The fastening structure according to claim 6, wherein the change of the fastening allowance is realized by changing the thickness of the loose washer. A fastening method characterized by preparing a plurality of types of loose washers having different shapes and forming different fastening allowances, and using the loose washers with shapes selected according to the fastening allowance dimensions of the fastening structure. .

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