JP3366215B2 - Press-fit structure of nut in terminal fixing part - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nut press-fitting structure in a terminal fixing portion for fixing a terminal to a housing.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional fusible link box. This fusible link box has a resin housing 1 and a terminal fixing portion 10 on a side surface of the housing 1. The nut 2 is press-fitted and fixed to the terminal fixing portion 10, and when the fusible link 3 is inserted into the housing 1, the terminal 4 of the fusible link 3 is fixed to the nut 2.
It is designed to be located in front of.

FIG. 6A shows a press-fitting structure for the nut 2. The nut 2 has a square bottom flange 2a. By pressing the side edge of the bottom flange 2a into a groove 1a provided in the housing 1 as a recess, the nut 1
It is fixed in a state where it is stopped from rotating. In this case, the groove 1a is set to a size such that the nut 2 does not rattle.

As shown in FIG. 5, fusible link 3 is used.
Along with the terminal 4 of, the LA terminal 5 of the end of the electric wire W is bolt 7
When the LA terminal 5 is fixed to the housing 1 with the LA terminal 5 overlaid on the terminal 4 of the fusible link 3 that is positioned in advance on the front surface of the nut 2, the through holes 4a of the terminals 4 and 5,
Pass the tip of the bolt 7 through 5a. Then, after the tip of the bolt 7 is tightened to the nut 2 by hand to the extent shown in FIG. 6A, the bolt 7 is completely tightened to the nut 2 using a tool such as an air wrench. Thereby, the terminals 4 and 5 are fixed to the housing 1 by the bolt 7 and the nut 2.

[0005]

However, in the prior art, as shown in FIG. 6B, the gap between the nut 2 and the terminals 4 and 5 is set narrow so that the nut 2 closely contacts the terminal 4 when the main tightening is completed. Therefore, when the tip of the bolt 7 is manually tightened to the nut 2 while using the through holes 4a and 5a of the terminals 4 and 5 as a guide, the play angle A of the bolt 7 regulated by the peripheral edge of the through holes 4a and 5a. Will become bigger. Therefore, bolt 7
It was a cause of tightening diagonally.

In view of the above circumstances, it is an object of the present invention to provide a nut press-fitting structure in a terminal fixing portion which can prevent diagonal tightening of a bolt and can reliably secure normal fastening strength. And

[0007]

According to a first aspect of the present invention, a nut is press-fitted into a recess of a housing so as to prevent rotation, a terminal is arranged in front of the nut, and a tip of a bolt is passed through a through hole of the terminal. , In the terminal fixing portion that fixes the terminal to the housing by screwing the tip of the bolt into the nut and tightening the nut, press the nut into the recess so that the nut can be moved to a position in which the nut is closely attached according to the tightening of the bolt. However, by holding the nut on the bottom side of the recess before tightening the bolt, a predetermined gap is secured between the nut and the terminal arranged on the front surface thereof.

In this structure, since a large distance is secured between the nut and the terminal before tightening the bolt, when the tip of the bolt passed through the through hole of the terminal is tightened to the nut by hand, The range of the play angle of the bolt restricted by the peripheral edge of the through hole is narrowed, and the bolt is prevented from being obliquely tightened. Then, when the bolt is further tightened, the nut moves correspondingly to the terminal side and finally comes into close contact with the terminal, so that the terminal can be securely fastened to the housing by the bolt and the nut.

According to a second aspect of the present invention, there is provided a press-fitting structure for a nut in the terminal fixing portion according to the first aspect, wherein a projection for preventing the nut from coming out is provided at a front end of the recess.

With this structure, the nut does not come out accidentally.

According to a third aspect of the present invention, there is provided a press-fitting structure for a nut in the terminal fixing portion according to the first or second aspect, wherein a force for holding the nut is generated on the inner wall of the recess according to the press-fitting of the nut. The rib is provided along the moving direction of the nut.

With this structure, the nut can be securely held at a position away from the terminal by the rib before tightening the bolt, and at the time of main tightening, the nut can be easily moved to the terminal side by sliding on the rib. It can be moved.

According to a fourth aspect of the present invention, there is provided a press-fitting structure for a nut in the terminal fixing portion according to any one of the first to third aspects, wherein the terminal is fitted with the nut when the terminal is arranged on the front surface of the nut. It is characterized in that a protrusion that widens the gap is provided.

In this structure, by providing the projection on the terminal side, the clearance before tightening between the nut and the terminal can be widened, so that the play angle of the bolt can be further narrowed. Further, even when there is no dimensional allowance on the recessed side of the housing, it is possible to widen the gap between the nut and the terminal and to narrow the play angle of the bolt.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

Since the entire structure of the fusible link box to which the present invention is applied is the same as that shown in FIG. 5, only the essential parts will be described. FIG. 1 is an enlarged view of the terminal fixing portion. In the figure,
The same parts as those in FIGS. 5 and 6 are designated by the same reference numerals.

In this terminal fixing portion, a margin in the depth direction is secured in the recess 11 into which the nut 2 is press fitted. Then, the nut 2 is press-fitted into the recess 11 so that it can be moved to a position in which the nut 2 comes into close contact with the terminal 4 in accordance with the tightening of the bolt 7. Particularly in that case, by holding the nut 2 on the bottom of the recess 11 before tightening the bolt, a predetermined large space S2 is secured between the nut 2 and the fusible link terminal 4 arranged on the front surface thereof. is doing. Here, the nut 2 is held in a fixed position by press-contacting both widthwise ends of the bottom flange 2a and the inner side wall 11a of the recess 11. In addition, a retaining protrusion 12 is provided at the front end of the recess 11, and the retaining protrusion 12 allows the nut 2 to move.
Is locked forward.

Next, the operation will be described.

In this structure, since a large space S2 between the nut 2 and the terminal 4 is secured before tightening the bolt, the bolt 7 inserted through the through holes 4a, 5a of the terminals 4, 5 is secured.
When tightening the tip of the
It is possible to narrow the range of the play angle B of the bolt 7 which is restricted by the peripheral edges of a and 5a. Therefore, as shown in FIG. 2A, the bolt 7 can be tightened straight without being obliquely tightened at the time of manual tightening.

When the bolt 7 is further tightened from this state, as shown in FIG. 2B, the nut 2 moves to the terminal 4 side in accordance with the tightening operation and finally comes into close contact with the terminal 4. . Therefore, the terminal 4 can be securely fastened to the housing 1 by the bolt 7 and the nut 2. Also, at the time of final tightening, the nut 2 moves to the terminal 4 side as shown in the figure,
By visually checking the position of the nut 2, the bolt 7
You can also find that you have forgotten to tighten.

As in the embodiment of FIG. 3, the recess 21
If several ribs 22 that generate a force for holding the nut 2 in accordance with the press-fitting of the nut 2 are provided in parallel to the inner side wall 21a of the nut 2 along the moving direction of the nut 2, the inside of the nut 2 and the recess 21 can be formed. Since it becomes possible to limit the contact portion of the wall 21a,
It is easy to press fit the nut 2. At the same time, the contact portion becomes clear, so that the nut 2 can be held securely before the tightening regardless of manufacturing error or the like. Therefore, it is possible to reliably secure the gap S2 having a predetermined size between the nut 2 and the terminal 4 when tightened by hand.

Further, since the contact portion is limited, when the nut 2 moves on the rib 22, the movement becomes smooth, and the workability at the time of final tightening with an air wrench or the like becomes good. The effect is also obtained.

Also, as in the embodiment of FIG.
It is also possible to secure a space S2 between the terminal 24 and the nut 2 by providing a protrusion 24a that abuts the stepped portion 23 on the housing 1 side. In such a case, by increasing the interval S2, it is possible to further narrow the play angle of the bolt at the time of manual tightening and prevent diagonal tightening. Further, in this example, since the protrusion 24a is provided on the terminal 24 side, even if there is no dimensional allowance on the recess 21 side of the housing 1, the gap S2 between the nut 2 and the terminal 24 can be widened. it can.

[0024]

As described above, according to the first aspect of the invention, a large gap is secured between the terminal and the nut during manual tightening, and the nut is brought into close contact with the terminal during final tightening. , It is possible to prevent diagonal tightening at the time of manual tightening, and it is possible to securely fix the terminal to the housing with bolts and nuts by full tightening. Further, since the nut moves to the terminal side at the time of final tightening, it is possible to detect forgetting to tighten the bolt by visually checking the position of the nut.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, it is possible to obtain a nut falling prevention effect.

According to the invention of claim 3, in addition to the effect of the invention of claim 1 or 2, the following effect is exhibited. That is, since the rib is provided on the inner surface of the recess, the contact portion between the nut and the recess is limited, and the nut can be easily press-fitted.
Further, since the contact portion becomes clear, the nut can be held reliably regardless of manufacturing errors or the like. Further, since the contact portion is limited, when the nut moves on the rib, the movement of the nut becomes smooth, and workability at the time of final tightening with an air wrench or the like becomes good.

According to the invention of claim 4, in addition to the effect of the invention of any one of claims 1 to 3, the following effect is exhibited. That is, even when there is no dimensional allowance on the concave side of the housing, the play angle of the bolt can be surely narrowed, whereby the problem of diagonal tightening during manual tightening can be solved.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an essential part of an embodiment of the present invention.

2A and 2B are operation explanatory views of the embodiment of the present invention, in which FIG. 2A is a sectional view showing a state at the time of manual tightening, and FIG.

FIG. 3 is a configuration diagram of a main part of another embodiment of the present invention,
(A) is a perspective view showing a state where a nut is about to be press-fitted into a recess formed in the housing, and (b) is a plan view after press-fitting.

FIG. 4 is a cross-sectional view showing a main part configuration of still another embodiment of the present invention.

FIG. 5 is a perspective view showing a terminal fixing portion of a conventional fusible link box.

6A and 6B show a nut press-fitting structure in a terminal fixing portion of a conventional fusible link, FIG. 6A is a cross-sectional view showing a state where regular hand tightening is performed, and FIG. 6B is a state in which diagonal tightening is performed. It is sectional drawing shown.

[Explanation of symbols]

1 housing 2 nuts 4,24 terminals 4a through hole 7 volts 11 recess 12 Lockout protrusion 21 recess 21a inner wall 22 ribs 24 terminals 24a protrusion

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01R 4/34 H01H 85/54 H01R 4/38 H01H 85/00

Claims (4)

(57) [Claims] 1. A nut is press-fitted into a recess of a housing so as to prevent rotation, a terminal is arranged in front of the nut, a tip of a bolt is passed through a through hole of the terminal, and the tip of the bolt is screwed into the nut. In the terminal fixing portion for fixing the terminal to the housing by tightening, the nut is press-fitted into the recess so as to be moved to a position in which the terminal is brought into close contact with the bolt according to the tightening of the bolt. By holding the nut on the bottom side of the recess, a predetermined gap is secured between the nut and the terminal arranged on the front surface of the nut. 2. The press-fitting structure for a nut in a terminal fixing portion according to claim 1, wherein a projection for preventing the nut from coming out forward is provided at a front end of the concave portion, and the nut is press-fitting in the terminal fixing portion. Construction. 3. The press-fitting structure for a nut in the terminal fixing portion according to claim 1, wherein a rib for generating a force for holding the nut in accordance with the press-fitting of the nut is provided on an inner wall of the recess. A structure for press-fitting a nut in a terminal fixing portion, which is provided along a moving direction. 4. The press-fitting structure for a nut in the terminal fixing portion according to claim 1, wherein a protrusion that widens a gap between the terminal and the nut when the terminal is arranged on the front surface of the nut. A structure for press-fitting a nut in a terminal fixing portion, characterized in that