JP2003120633A - Looseness preventive screw for set screw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To epochally improve a defect of suffering for even disassembling- assembling thereafter by adopting a special looseness preventive screw because of lacking in an effect in a means for preventing looseness by applying an adhesive after fastening a set screw threadedly engaged with an installing screw hole of a flange to a shaft when fixing the shaft and a flange. SOLUTION: After fixing one member B to the other part A by threadedly engaging and fastening the set screw 11 with and to the installing screw hole 1, a looseness preventive screw body 12A is also threadedly engaged. A protrusive part 12c with a base end side abutting inclined peripheral surface 12d formed at an equal chamfer angle α is protrusively arranged with the axis Y2 eccentric from the axis Y1 of the looseness preventive screw body to a conical receiving-supporting inclined peripheral surface 11d applied at the chamfer angle α tapering in the depth direction in an axial inlet part of a head part side threadedly rotating port 11b in the set screw 11. A base end side abutting inclined peripheral surface 12d of the protrusive part 12c for eccentrically rotating the looseness preventive screw body 12A freely abuts and stops to the conical receiving-supporting inclined peripheral surface 11d in a line contact state, and generates large frictional force against the looseness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single component such as a shaft by fitting another component such as a flange and screwing it into a mounting screw hole formed through the flange. On the other hand, the present invention relates to a loosening prevention screw for a set screw, which is used by applying to the attachment screw hole, in order to prevent the set screw that has been installed from loosening due to vibration when fixing other parts.

[0002]

2. Description of the Related Art As shown in FIG. 3, in order to fix a fitted flange 2 to a shaft 1, a set screw 3 having a hexagonal hole 3a in a mounting screw hole 2a penetrating the flange 2 is provided. The hexagonal bar spanner (not shown) is engaged with the hexagonal hole 3a and screwed, so that the preceding fastening end portion 3b of the set screw 3 is fastened to the shaft 1. Therefore, when the set screw 3 is used, the internal thread of the attachment screw hole 2a is based on the frictional force between the preceding fastening end portion 3b and the contact surface 1a of the shaft 1 and the axial force generated by the tightening of the set screw 3. The frictional force generated between the portion 2b and the male screw portion 3c of the set screw 3 suppresses the rotation of the set screw 3 in the loosening direction.

However, when the set screw 3 is used, the set screw 3 may be unintentionally loosened due to the increase or decrease of the above-mentioned frictional force based on the vibration generated from various devices as is known. Therefore, for the purpose of extinguishing the relaxation, as an already-implemented means, an adhesive is applied to the male screw portion 3c of the set screw 3 and the male screw portion 3c of the flange 2 as described above. According to the means, when the fixing strength by the adhesive is weak, the loosening prevention effect of the set screw 3 becomes weak. When a strong adhesive that can correct this is used, the set screw 3 is removed and the shaft 1 is removed. It is impossible to eliminate the defects that the disassembly of the flange 2 and the flange 2 is substantially impossible, and the disassembly work and the assembly work thereof are difficult.

[0004]

SUMMARY OF THE INVENTION The present invention has been studied in view of the deficiency of the loosening prevention means of the above-mentioned conventional set screw, and an adhesive agent is used to prevent the undesired loose rotation of the set screw 3 described above. Instead of trying to prevent it by the construction of
In the first aspect, the loosening prevention screw is separately heavy-fitted into the attachment screw hole into which the set screw is screwed and fastened. At this time, the hexagonal hole 3a of the set screw or the like is previously used. A mortar-shaped receiving inclined peripheral surface formed at a predetermined chamfering angle is formed at the axial center inlet portion of a certain head side screw opening.

The loosening prevention screw according to the present invention is provided with a protrusion having a chamfering angle equivalent to that of the mortar-shaped receiving inclined peripheral surface and having a base end side contact peripheral surface at an eccentric position. By providing the loosening prevention screw by rotationally fitting the loosening prevention screw into the attachment screw hole, the protrusion is pushed into the head side screw opening of the set screw, and thus the eccentricity of the protrusion is concerned. The base end side contact peripheral surface is configured so that it can be stopped in line contact with the mortar-shaped receiving inclined peripheral surface of the set screw.

As described above, the present invention realizes the tightening in which the line contact state inclined with the axis is obtained with the above chamfer angle, whereby the pressing force (axial force) by the loosening prevention screw in the axial direction is achieved. ) Is received by the set screw, and the loosening prevention screw receives the reaction force based on the pressing force in the opposite direction by the set screw, so that a large frictional force can be generated between the two screws. Further, in the present invention, even in the direction orthogonal to the axis, both screws are also subjected to a large pressing force and reaction force in opposite directions, and similarly, a large frictional force can be generated. The sum of the two frictional forces mentioned above makes it possible to prevent loosening of the set screw and the loosening prevention screw with extremely high reliability, and not only the fixing strength but also the disassembly and re-assembly of parts as compared with the conventional adhesive application means. The aim is to make the assembly also feasible.

According to Claim 2, the above Claim 1
In the above, by forming the protrusion of the loosening prevention screw main body into a conical shape by the base end side contact peripheral surface and the spherical surface portion continuously provided on the tip side thereof, the loosening prevention screw is attached to the attachment screw hole. At the time of tightening by screwing, it is ensured that the protrusion enters into the head side screwing opening of the set screw without any trouble, so that the above-mentioned object of claim 1 is surely achieved.

[0008]

SUMMARY OF THE INVENTION According to the present invention, in order to achieve the above-mentioned object, a turning tool which is engaged with a head side screw opening is attached to a mounting screw hole of another part which should be fixed to one part. Rotation of
Anti-loosening screw that can be tightened by applying turning force to the top screwing part in the mounting screw hole by a turning tool to the set screw whose preceding tightening end can be tightened to the above-mentioned one component. And, on the set screw side of the loosening prevention screw body, at a predetermined chamfering angle so as to taper toward the depth at the axial center inlet part of the head side screw opening of the set screw. A protrusion having a base end side contact inclined peripheral surface formed at the same chamfer angle with respect to the mortar-shaped receiving inclined peripheral surface that is constructed is raised with an axis eccentric from the axis of the loosening prevention screw body. The inclined peripheral surface of the base end side of the protruding portion that is eccentrically rotated by the rotation tool of the loosening prevention screw body is in line contact with the inclined peripheral surface of the mortar-shaped receiving screw of the set screw. A stop characterized by being able to stop and contact We are trying to provide an anti-loosening screws of use.

According to a second aspect of the present invention, in the loosening prevention screw for a set screw according to the first aspect, the protrusion formed on the loosening prevention screw body has a base end side contact inclined peripheral surface,
The content is that it is formed in a conical shape with a spherical surface portion that is continuously formed by taking a spherical surface on the tip side.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail with reference to FIGS. 1 and 2. In FIG.
An embodiment in which another component B as a flange or the like is fitted and a set screw 11 and a loosening prevention screw 12 according to the present invention are sequentially screwed into a mounting screw hole 10 penetrating the other component B is provided. It is disclosed. First, the set screw 11 to be screwed into the attachment screw hole 10 will be explained first.
As shown in (A), an outer peripheral set screw portion 11a, and a head side screw opening 11b which is used for turning by engaging a turning tool such as a hexagonal bar wrench like a known hexagonal hole, It has a flat leading fastening end portion 11c formed on the opposite side thereof. Further, at the shaft center inlet portion of the head side screwing port 11b, it is constructed at a predetermined chamfering angle α so as to be tapered toward the depth, that is, the side of the preceding fastening end 11c. The mortar-shaped receiving inclined peripheral surface 11d is formed.

As is well known, the set screw 11 is preceded by the turning tool engaged with the head side screw opening 11b with respect to the attachment screw hole 10 of the other component B. The fastening end portion 11c can be fastened to the outer surface portion a of the one component A so that the one component A and the other component B are fixed. Therefore, after this fixed state, the set screw 12 that will also be screwed into the attachment screw hole 10,
This will also be described below with reference to FIGS. 1 and 2A and 2B. The loosening prevention screw 12 has a loosening screw body 1
The outer peripheral loosening prevention screw portion 12a and a turning tool such as a known hexagonal hole are engaged with 2A, or a top side screw screw having an appropriate structure formed by providing a prismatic protrusion (not shown). The turning portion 12b and the opposite set screw 11
It has a protrusion 12c formed on the side.

In the above-mentioned projection 12c, there is provided a base end side contact inclined peripheral surface 12d formed with a chamfering angle α equivalent to that of the mortar-shaped receiving inclined peripheral surface 11d described above. The abutment inclined peripheral surface 12d on the base end side is elevated with an axis Y2 of a protrusion eccentric from the axis Y1 of the loosening prevention screw body 12A by a required length d. Therefore, as described above, by screwing the loosening prevention screw 12 into the attachment screw hole 10 by screwing with the turning tool, the eccentric rotation of the protrusion 12c in the loosening prevention screw body 12A causes the proximal end side. The abutting inclined peripheral surface 12d does not contact the entire mortar-shaped receiving inclined peripheral surface 11d of the set screw 11, but stops contacting in a line contact state. 1, the LF indicates the line contact point.

Since the loosening prevention screw 12 according to claim 1 is configured as described above, the protrusion 12c has the loosening prevention screw main body 12A as described above as understood from FIG.
Since it is eccentric from the center Y1 of the axis, it does not evenly contact the mortar-shaped receiving inclined peripheral surface 11d of the set screw 11, and only the eccentric side makes line contact. Moreover, at this time, since both sides of the base end side contact inclined peripheral surface 12d and the mortar-shaped receiving inclined peripheral surface 11d are formed with the chamfering angle α, by the above-mentioned tightening of the loosening prevention screw 12, the same figure is used. For the downward axial force P that is in the axial direction,
Not only the upward axial force that is the reaction force is generated, but also the lateral inward force F that is the reaction force is generated with respect to the lateral outward force F that is orthogonal to the axial direction.

Therefore, according to the present invention, the outer peripheral set screw portion 11a of the set screw 11 is pressed downward in FIG. 1 by the above-mentioned downward axial force P, and the outer peripheral loosening preventive screw portion of the loosening prevention screw 12 becomes Undesired loosening of the set screw 11 and the loosening prevention screw 12 is prevented by a large frictional force due to the axial force (pressing force) that is pressed upward and is in the opposite direction. The effect of such loosening prevention can be evaluated as an equivalent effect content although the structure is different, as compared with the double nut in the separately known nut loosening prevention method.

However, in the present invention, not only the effect based on the frictional force as described above, but also a large pressing force, that is, the outward force F and the inward force F, which are laterally opposite to each other as described above, act on each other. Therefore, the attachment screw hole 10 described in the above
On the other hand, the action force of the outer peripheral stop screw portion 11a and the outer peripheral loosening prevention screw portion 12a is also applied from the lateral direction, so that a large frictional force can be obtained. As a result, not only the frictional force based on the above-mentioned opposite upward and downward axial forces P, P, but also the frictional force based on the opposite outward lateral force F and inward force F are added. The total frictional force can maximize the function of preventing loosening.

Next, the claim 2 showing one embodiment of the claim 1 will be explained. Here, as described above, the protrusion 12 is formed only by the base end side contact inclined peripheral surface 12d according to claim 1.
12d without forming d
The entire surface is formed into a conical shape by the spherical surface portion 12e which is provided on the tip side of the spherical surface and is continuously formed by taking a spherical surface. In this way, the spherical portion 1
Since the 2e is provided in a protruding manner, when the loosening prevention screw 12 is screwed in, the protrusion 12c is rotated,
There is nothing that hits the spherical surface portion 12e, so that the smooth rotation of the loosening prevention screw 12 can always be guaranteed, and the intended purpose can be smoothed without hindering the above-described operation of claim 1. Can be achieved.

[0017]

Since the present invention is constituted as described above, when the loosening prevention screw for the set screw according to claim 1 is used, the one part is fixed to the attachment screw hole for fixing the one part. Not only the set screw can be screwed and tightened, but also a loosening prevention screw prepared separately can be screwed and tightened to the set screw. In addition, at this time, the base end side contacting inclined peripheral surface of the eccentric protrusion of the loosening prevention screw is brought into line contact with the mortar-shaped receiving inclined peripheral surface formed on the set screw to stop the contact. You will get it.

As a result, due to the above-mentioned tightening, the pressing forces in the directions opposite to each other act between the set screw and the loosening prevention screw, and even in the direction orthogonal to the axial force, the set screw and the loosening prevention screw are prevented. Between the screws, the pressing forces in the opposite directions act on each other. As a result, it is possible to exert a far greater total frictional force than the loosening prevention means by the double nut, so not only is there a great effect in preventing the loosening as compared with the conventional adhesive application means. As compared with the case where the high-strength adhesive is used, the disassembling and assembling work of one component and the other component can be performed easily and quickly. Further, when the protrusion portion of the loosening prevention screw is formed in a conical shape by the base end side contact inclined peripheral surface and the spherical portion continuous with this, the screwing of the loosening prevention screw is hindered. Without doing so, the loosening prevention screw can be further improved in reliability.

[Brief description of drawings]

FIG. 1 is a view showing a loosening prevention screw for a set screw according to the present invention.
It is a partially longitudinal front view when one component and another component are fixed.

FIG. 2A is a vertical sectional front view showing the mutual relationship between the set screw and the loosening prevention screw, and FIG. 2B is a vertical sectional right side view of the same loosening prevention screw.

FIG. 3 shows a conventional set screw, (A) is a plan view thereof,
(B) is a vertical sectional front view of a main part in a use state.

[Explanation of symbols]

10 Mounting screw holes 11 Set screw 11b Head side screw opening 11c Leading fastening end 11d Mortar-shaped receiving inclined peripheral surface 12 Loosening prevention screw 12A Loosening prevention screw body 12b Top side screwing part 12c protrusion 12d Base end side contact inclined peripheral surface 12e spherical surface A one part B Other parts LF line contact point α chamfer angle

Claims (2)

[Claims] 1. The preceding fastening end portion is formed in the attachment screw hole of another component to be fixed to the one component by the rotation of a rotation tool engaged with the head side screwing opening. In contrast to the set screw that can be tightened freely, it is a loosening prevention screw that can be tightened by applying a turning force to the top side screwing portion by a turning tool to the mounting screw hole. On the set screw side, there is a mortar-shaped sloping peripheral surface at the axial inlet of the head side screw opening of this set screw, which is constructed at a predetermined chamfer angle so as to taper toward the depth. On the other hand, the protrusion having the proximal contact side inclined peripheral surface formed at the same chamfering angle is raised with an axis eccentric from the axis of the loosening prevention screw body, and The base end side contact inclined peripheral surface of the protrusion that is eccentrically rotated by the moving tool is a set screw. 2. A loosening prevention screw for a set screw, which is capable of abutting and stopping freely in a line contact state with the above-mentioned mortar-shaped inclined inclined peripheral surface. 2. The protrusion formed on the loosening prevention screw main body is formed in a conical shape by a base end side contact inclined peripheral surface and a spherical surface portion continuously provided on the tip end side by taking a spherical surface. A loosening prevention screw for a set screw according to Item 1.