JPH10318233A - Fixing structure by centering bolt or nut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably fix members to be fastened at each other as a centering bolt or nut is used in common. SOLUTION: An insertion hole 2a of member 2 to be fastened is formed in the same shape in cross section as that of combination of a circle 4, having diameter enough to allow insertion of the large diameter part 3b of a centering bolt 3, and an oblong circle 5 having width enough to allow insertion of only a screw shaft 3a. Deviation between the mounting hole 1a of a member 1 to be fastened and the insertion hole 2a is absorbed by inserting the screw shaft 3a in the part of an oblong circle 5 and the screw shaft 3 is threadedly engaged with the mounting hole 1a. From this state, the centering bolt 3 is fastened and a working face 3c is brought into contact with a chamfer 6 processed on the opening part of an insertion hole. The working face 3c is guided to the chamfer 6, and the screw shaft 3a is centered at the insertion hole 2a. The large diameter part 30b of a centering bolt 3 is fitted into the part 4, formed in a circular shape in cross section, of the insertion hole 2a and fastening is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a dimensional error of a part,
The present invention relates to a fixing structure using a centering bolt or a nut capable of fixing a member to be fastened while correcting a pitch shift of a mounting hole that may occur between a plurality of members to be fastened due to accumulation of assembly errors and the like.

[0002]

2. Description of the Related Art In fixing one member to be fastened 1 (for example, a body of an automobile) and the other member to be fastened 2 (for example, a reinforcement of a vehicle) shown in FIG. Due to accumulation of errors and the like, a deviation (arrow B) may occur between the pitch dimension A set in the mounting holes of the members to be fastened 1 and 2 and the actual pitch dimension. In such a case, the bolts 3 (so-called centering bolts) shown in FIG. 7 are used to match the mounting hole pitch of the member to be fastened 2 with the mounting hole pitch of the member to be fastened 1, and then the members 1, 2 are fastened. It is necessary to fix in between.

The centering bolt 3 has a large diameter portion 3b at the root of a screw shaft 3a and a substantially conical contact surface 3c between the large diameter portion 3b and the screw shaft 3a. . The diameter D ₂ of the large diameter portion 3b is equal to the diameter D of the screw shaft 3a.
_The diameter is larger than ₁ . Further, the mounting holes 1a are nominal diameter D ₁ of the screw shaft 3a provided in the fastened member 1, the insertion hole 2a is a mounting hole provided in the fastened member 2 has a diameter D ₂
Are respectively set.

That is, since (diameter D ₂ of insertion hole 2a)> (diameter D ₁ of screw shaft 3a), the center between mounting hole 1a and insertion hole 2a is shifted as described above. Also, only the screw shaft 3a of the centering bolt 3 is passed through the insertion hole 2a of the member 2
a can be screwed. From this state, as the centering bolt 3 is tightened into the mounting hole 1a, the contact surface 3a comes into contact with the edge of the insertion hole 2a, and the contact surface 3 is guided by the edge of the insertion hole 1a. Push up the pitch. Then, the mounting hole 1a is corrected until the large-diameter portion 3b comes to a position where it can be fitted into the insertion hole 2a (a position where the pitch between the mounting hole 1a and the insertion hole 2a is the same). Then
As shown in FIG. 7, it is possible to tighten the large diameter portion 3b of the centering bolt 3 until the large diameter portion 3b is completely fitted in the insertion hole 2a (fastened state).

[0005]

However, the conventional fixing structure using the centering bolt has the following problems. As shown in FIG. 6, due to the accumulation of dimensional errors and assembly errors of the components, the pitch A set in the mounting holes of the members 1 and 2 shifts from the actual pitch (arrow B). Occurs, the factors of the deviation of the pitch dimension are various, such as the material of the component, the processing method, the shape, and the like. Therefore, it is difficult to predict the magnitude of the deviation at the time of designing.

Accordingly, when the deviation in size of the center line C ₂ of the center line C ₁ and the insertion hole 2a of the mounting holes 1a as in Fig. 8, which is passed through the screw shaft 3a into the insertion hole 2a, the mounting holes 1a the center axis C ₁ of the central axis C of the centering bolt 3
Sometimes it may spread to such an extent that can not be matched with ₃ and. In such a case, it becomes impossible to screw the screw shaft 3a penetrating through the insertion hole 2a with the mounting hole 1a. Further, if excessive screwing is performed in this state, the possibility of occurrence of so-called incomplete screw fastening, which is a state in which the centering bolt 3 is obliquely inserted into the mounting hole 1a and tightened, increases. .

As shown in FIG. 8, as a countermeasure for the case where the displacement between the mounting hole 1a and the insertion hole 2a has become larger than an allowable amount, as shown in FIG.
And the diameter of the large diameter portion 3b of the centering bolt 3 is D ₂ ′
(D ₂ ′> D ₂ ). By taking this measure, the screw shaft 3a penetrating through the insertion hole 2a can be screwed into the mounting hole 1a without difficulty even if the pitch shift between the mounting hole 1a and the insertion hole 2a is the same as in FIG. To do. However, according to this method, the screw shaft 3a
However, it is necessary to provide various types of centering bolts 3 having different diameters of the large-diameter portions 3b and the corresponding through holes 2a while having the same nominal diameter. Further, as described above, it is difficult to predict the size of the deviation between the pitch of the mounting holes 1a and the pitch of the insertion holes 2a at the time of design, and the design of each dimension must be changed during product development. There were many things.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object the purpose of making the centering bolt or the nut common at various places of use, while maintaining the pitch of the mounting holes between the members to be fastened. The object is to reliably correct the displacement and surely fix the members to be fastened.

[0009]

According to the present invention, there is provided a centering bolt or nut having a substantially conical contact surface, and the contact surface is provided with a through hole of a member to be fastened. A structure for fixing a plurality of members to be fastened to each other while performing centering, wherein a cross-sectional shape of an insertion hole of the member to be fastened is a circle having a diameter capable of inserting a maximum diameter portion of the contact surface, and the centering bolt. Alternatively, it is characterized in that it is constituted by combining an ellipse having a width that allows only the screw shaft related to the nut to be inserted, and the opening of the insertion hole is chamfered beyond the range of the ellipse.

According to the present invention, the cross-sectional shape of the insertion hole of the member to be fastened is such that only a circle having a diameter capable of inserting the maximum diameter portion of the contact surface and the screw shaft related to the centering bolt or nut can be inserted. And a screw shaft related to the centering bolt or nut and the insertion hole are caused to penetrate the screw shaft through a portion having the oval cross section. Thus, the screw shaft is screwed with the engagement hole or the nut. Then, by tightening the centering bolt or the nut, the substantially conical contact surface provided on the nut or the nut is brought into contact with the chamfer formed in the opening of the insertion hole. Since the chamfering is performed in a wider area than the range of the ellipse, even if the screw shaft is located at the end of the ellipse, the hitting surface and the chamfering are securely applied. Can be in contact. And by further tightening, the contact surface is guided to the chamfer,
Centering the screw shaft in the insertion hole. And
In the insertion hole, the contact surface of the centering bolt or the nut is fitted to a portion having a cross section having a circle having a diameter capable of inserting the maximum diameter portion of the contact surface, thereby completing the fastening.

In the present invention, the longitudinal direction of the ellipse is made to coincide with a direction in which a pitch shift may occur between the insertion hole of the member to be fastened and a screw shaft of a centering bolt or a nut. Is desirable. With this configuration, the ability to absorb the displacement between the screw shaft related to the centering bolt or the nut and the insertion hole is maximized.

Further, the insertion hole may be formed in a collar which is detachable from the member to be fastened. According to this configuration, by attaching / detaching only the collar having a different shape of the formed insertion hole to / from the member to be fastened, the combination of the screw shaft related to the centering bolt or the nut and the insertion hole can be used to reduce the displacement of these. Optimum according to the amount.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, the same or corresponding parts as in the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 1 shows a state in which the centering bolt 3 is tightened in the fixing structure using the centering bolt according to the first embodiment of the present invention in order (a).
To (c). Here centering bolts 3 used in the large-diameter portion 3b of diameter D ₂ as described in FIG. 8,
Is the same as the centering bolt having a threaded shaft 3a of the diameter (nominal diameter) D _1. A flange 3d is provided at the base of the large diameter portion 3b of the centering bolt.

Also in this embodiment, one member 1 to be fastened and the other member 2 to be fastened are fixed using the centering bolt 3. By the way, the insertion hole 2a of the member to be fastened 2 has features as shown in FIGS. First, the cross-sectional shape of the insertion hole 2a is such that the maximum diameter portion of the contact surface 3c of the centering bolt 3 can be inserted.
b and circle 4 forming a can be inserted diameter D _2, and it is assumed that a combination to match the center of the ellipse 5 having only the screw shaft 3a of the centering bolt 3 can be inserted width D _1.
In addition, the opening of the insertion hole 2 a is chamfered 6 beyond the range of the oval 5. Furthermore, the longitudinal direction of the ellipse 5
A direction in which a pitch shift may occur between the insertion hole 2a of the member 2 to be fastened and the screw shaft 3a of the centering bolt 3 (FIG. 3).
Left and right directions).

Here, a procedure for fixing the members to be fastened 1 and 2 using the centering bolt 3 will be described with reference to FIG.

[0017] Initially, the center line C ₁ of the mounting holes 1a of the fastening member 1 as shown in FIG. 1 (a), off occurs between the center line C ₂ of the insertion hole 2a of the workpieces 2 ing. In this state, the screw shaft 3a of the centering bolt 3, by passing through the portion of the ellipse 5 having a width D ₁ of the insertion hole 2a, to match the center line C ₃ to the center line C ₁ of the mounting holes 1a be able to. Therefore, the screw shaft 3a can be screwed into the mounting hole 1a without difficulty. That is, the screw shaft 3 of the centering bolt 3 is inserted into the oval 5 of the insertion hole 2a.
a can be made to penetrate through the mounting hole 1a.
Centering bolt 3 resulting from displacement between the hole and the insertion hole 2a
And the insertion hole 2a can be absorbed.

Next, as shown in FIG. 1 (b), by tightening the centering bolt 3, the contact surface 3c of the centering bolt 3 is brought into contact with the chamfer 6 formed in the opening of the insertion hole 2a. Can be. Incidentally, the chamfer 6 is provided in a wider area than the area where the oval 5 is formed. Therefore, even if the screw shaft 3a is located at the end of the ellipse 5 as shown in FIG.
And the chamfer 6 can be reliably brought into contact with each other. Then, by further tightening, the contact surface 3a is guided to the chamfer 6, and the centering bolt 3 and the member 1 to be moved move to the left side of the member 2 with respect to the member 2 to be fastened. It can be seen that the distance between the center axes C ₁ and C ₃ and the center line C ₂ in FIG. 1B is smaller than the state in FIG. 1A.

Further, tightening of the centering bolt 3
And finally the central axis C as shown in FIG.
₁ , C_Three And center line C_Two Is the state that matches, that is,
Mandrel C ₁ , C_Two , C_Three All are centered
Becomes At this time, the large diameter portion 3b of the centering bolt 3
And the section 4 in which the cross section of the insertion hole 2a is circular matches.
Therefore, below the neck of the centering bolt 3 (from the flange 3d)
The lower part) completely fits into the insertion hole 2a,
The lower surface of the die 3d is in close contact with the member to be fastened.

The operation and effect obtained from the first embodiment of the present invention having the above configuration are as follows. First, the cross-sectional shape of the insertion hole 2a of the fastener 2, circle 4 of diameter D ₂
When, by the a combination to match the center of the oval 5 of width D _1, and the screw shaft 3a of the centering bolt 3, the deviation of the insertion hole 2a, the portion 5 having an oval shaped cross-section By absorbing the screw shaft 3a by penetrating it, the screw shaft 3a can be screwed into the mounting hole 1a of the member 1 to be fastened. Therefore, various types of centering bolts 3 having different diameters of the large-diameter portions 3b and the corresponding insertion holes 2a are prepared in accordance with the size of the displacement between the screw shaft 3a and the insertion hole 2a as in the related art. This eliminates the necessity, and one type of centering bolt and the insertion hole 2a can reliably correct the deviation of the pitch of the mounting hole between the members to be fastened, and securely fix the members to be fastened. Moreover, since the longitudinal direction of the ellipse 5 coincides with the direction in which the displacement occurs between the insertion hole 2a of the member 2 to be fastened and the screw shaft 3a of the centering bolt 3, the screw shaft 3a of the centering bolt 3
The ability to absorb the deviation from the insertion hole 2a can be maximized.

When the centering bolt 3 is tightened, the contact surface 3c comes into contact with the chamfer 6 formed in the opening of the insertion hole 2a, the contact surface 3c is guided by the chamfer 6, and the centering bolt 3 and the insertion hole are inserted. 2a can be reliably centered. Then, to complete the large-diameter portion 3b of the centering bolt 3, by which the cross-sectional shape of the insertion hole 2a is fitted into the portion 4 forming a circle of diameter D _2, the coupling of the workpieces 1 and 2 by the centering bolt 3 be able to.

Next, a second embodiment of the present invention will be described with reference to FIG. Here, the same or corresponding portions as those in the conventional example or the first embodiment of the present invention are denoted by the same reference numerals, and detailed description is omitted.

In the second embodiment of the present invention, a through hole 7 is formed in the member 2 to be fastened, and a detachable collar 8 is fitted into the through hole 7. And in this color 8,
An insertion hole 2a having the same cross-sectional shape as that described in the first embodiment is formed. Further, similarly to the first embodiment, the opening of the insertion hole 2 a is chamfered 6 beyond the range of the oval 5.

According to the second embodiment of the present invention, by changing the collar 8, it becomes easy to change the shape of the insertion hole 2a in various ways. Therefore, it is possible to optimize the combination of the centering bolt 3 and the insertion hole 2a according to the amount of these shifts. In addition, regarding the same operation and effect as the first embodiment,
The description here is omitted.

Although not shown, only the screw shaft 3a of the centering bolt 3 is implanted in the member 1 to be fastened, and a centering nut having a large-diameter portion 3b, a contact surface 3c and a flange 3d is screwed thereto. Accordingly, the same operation and effect as those of the above embodiment can be obtained.

[0026]

According to the present invention, the following effects are obtained. First, according to the fixing structure using the centering bolt or the nut according to claim 1 of the present invention, the cross-sectional shape of the insertion hole of the member to be fastened,
By combining a circle having a diameter allowing insertion of the maximum diameter portion of the contact surface and an ellipse having a width capable of inserting only the screw shaft related to the centering bolt or nut, as in the related art, There is no need to prepare various kinds of centering bolts and nuts with different diameters of the large diameter part and corresponding through holes according to the size of the deviation between the screw shaft and the insertion hole. With the insertion hole, it is possible to reliably correct the deviation of the pitch of the mounting hole between the members to be fastened, and to surely fix the members to be fastened.

According to the fixing structure using the centering bolt or the nut according to the second aspect of the present invention, the longitudinal direction of the oval is set between the insertion hole of the member to be fastened and the screw shaft of the centering bolt or the nut. By aligning the pitch with the direction in which the pitch may be shifted, the capacity of absorbing the shift between the screw shaft of the centering bolt or the nut and the insertion hole is maximized, and the centering bolt or the nut is inserted through one kind of the centering bolt or the nut. With the holes, the deviation of the pitch of the mounting holes between the members to be fastened can be corrected reliably, and the members to be fastened can be securely fixed.

Further, according to the fixing structure using the centering bolt or the nut according to the third aspect of the present invention, the collar can be replaced by forming the insertion hole in a collar detachable from the member to be fastened. This makes it easy to optimize the combination of the screw shaft relating to the centering bolt or the nut and the insertion hole according to the amount of displacement occurring between them. Therefore, it is possible to more reliably fix the members to be fastened.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a fixing structure using a centering bolt according to a first embodiment of the present invention, showing a fixing procedure.

FIG. 2 is a perspective view showing an insertion hole of a centering bolt provided in a member to be fastened shown in FIG. 1;

FIG. 3 is a plan view of the insertion hole shown in FIG. 2;

FIG. 4 is a sectional view taken along line EE in FIG. 3;

FIG. 5 is a schematic sectional view showing a fixing structure using a centering bolt according to a second embodiment of the present invention.

FIG. 6 is a schematic diagram showing a state of a pitch shift that can occur between two members to be fastened.

FIG. 7 is a schematic sectional view showing a fixing structure using a conventional centering bolt.

8 is a schematic cross-sectional view showing a problem in the fixing structure using the centering bolt shown in FIG.

FIG. 9 is a schematic cross-sectional view showing one means for solving the problem shown in FIG. 8 in a conventional fixing structure using a centering bolt.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Fastened member 1a Mounting hole 2 Fastened member 2a Inserting hole 3 Centering bolt 3a Screw shaft 3b Large diameter portion 3c Contact surface 4 Circle having a diameter capable of inserting the maximum diameter portion of the contact surface 5 Only screw shaft can be inserted Oval with width 6 Chamfer C ₁ Center axis of mounting hole C ₂ Center axis of insertion hole C ₃ Center axis of centering bolt

Claims (3)

[Claims] 1. A structure in which a plurality of members to be fastened are fixed to each other using a centering bolt or nut having a substantially conical contact surface, while centering the member to be inserted into an insertion hole by the contact surface. The cross-sectional shape of the insertion hole of the member to be fastened, a circle having a diameter capable of inserting the largest diameter portion of the contact surface, and an ellipse having a width capable of inserting only the screw shaft related to the centering bolt or nut. A fixing structure using a centering bolt or nut, wherein the fixing hole is formed in combination, and an opening of the insertion hole is chamfered beyond a range of the oval. 2. The device according to claim 1, wherein a longitudinal direction of the ellipse coincides with a direction in which a pitch shift may occur between an insertion hole of the member to be fastened and a screw shaft of a centering bolt or a nut. Fixed structure with centering bolts or nuts. 3. The fixing structure according to claim 1, wherein the insertion hole is formed in a collar detachable from the member to be fastened.