CN203311943U - Insulator - Google Patents

Abstract

The utility model provides an insulator. The insulator (1) has a side wall (121) and a bottom surface (122a) for surrounding the fastening bolt (4), and a depression is formed at the junction (123) where the side wall (121) and the bottom surface (122a) intersect To the inner surface of the side wall (121) and the groove (13) in the bottom surface (122a). By adopting the structure of the utility model, it is possible to prevent cracks at the intersection portion (123) where the side wall (121) and the bottom surface (122a) intersect, and to ensure the abutting length of the bolts.

Description

insulator

technical field

The utility model relates to an insulator, in particular to an insulator used for connecting parts of conductive strips of batteries and the like. the

Background technique

When connecting batteries in series or in parallel, or outputting electric energy of the batteries to the outside, etc., it is necessary to connect busbars to the external terminals of the batteries. And, in the connection structure between the conductive strip and the external terminal of the battery, fastening bolts and nuts need to be used. For example, first place the fastening bolts in the insulator provided on the battery casing (cover), then put the through holes of the external terminals and conductive strips on the fastening bolts, then put the nuts on the fastening bolts and tighten them , the conductive strips can be connected to external terminals (for example, refer to Patent Documents 1 and 2). In order to enable the insulator used in the connecting structure of the bus bar to hold the fastening bolt, the insulator is provided with a side wall for surrounding the bolt head of the fastening bolt. The effect of the side wall is to prevent the fastening bolt from rotating when the nut is tightened. the

However, when the nut is tightened to fasten the bus bar, the side wall of the insulator is inclined outward due to being pressed by the head of the bolt, so that the stress concentrates on the corner where the side wall meets the bottom surface of the insulator, which may cause the corner to be damaged. Create cracks. As a solution to this problem, the sidewall of the insulator may be thickened to reduce the amount of inclination of the sidewall. However, increasing the thickness of the side wall will increase the thickness of the battery. Therefore, increasing the thickness of the side wall is not the best policy. In addition, the concentration of stress can be alleviated by forming the intersection of the side wall and the bottom surface of the insulator into an arcuate corner. In this case, as shown in FIG. 8 , the inner surface of the side wall 321 and the bottom surface 322 a of the insulator shrink toward the inner side at the arc angle R. Therefore, it is necessary to cut the corner edge of the bolt head 4a to correspond to the shape of the arc corner R. This shortens the contact length K of the bolt (the length of the contact portion between the bolt head 4 a and the side wall 321 of the insulator 301 ). the

[Patent Document 1]: Japanese Patent Laid-Open No. 2010-282847

[Patent Document 2]: Japanese Patent Application Publication No. 2011-066014

Utility model content

In view of the above problems, the purpose of this utility model is to provide a method that can prevent cracks at the junction (corner) where the side wall and bottom surface of the bolt head (bolt fastening part) surrounding the fastening bolt intersects, and ensure that An insulator for the butt length of the bolt. the

As a technical solution to solve the above-mentioned technical problems, the insulator of the present invention has side walls and a bottom surface for surrounding bolt fastening parts (for example, bolt heads of fastening bolts), and where the side walls intersect the bottom surface The junction portion (corner portion) is formed with a groove recessed into the inner surface of the side wall and the bottom surface. the

The advantage of the insulator of the present invention is that a groove is formed at the intersection (corner) where the side wall and the bottom of the insulator intersect. Stress concentration can be alleviated (stress can be dispersed), so that cracks can be prevented from occurring at the interface where the side wall meets the bottom surface. Furthermore, the groove has a concave shape (cross-sectional shape) sunk into the inner surface of the side wall and the bottom surface, and the inner surface and the bottom surface of the side wall do not shrink toward the inner side. Therefore, it is not necessary to cut the bolt fastening member (for example, the bolt head), and the contact length of the bolt fastening member can be ensured. the

Description of drawings

FIG. 1 is a cross-sectional view showing an example of a bus bar connection structure of a battery using the insulator of the present invention. the

Fig. 2 is a perspective view of an insulator and fastening bolts. the

Fig. 3 is a top view of the insulator. the

4(A) to 4(D) are diagrams showing examples of cross-sectional shapes of grooves formed on an insulator. the

5(A) to 5(D) are diagrams illustrating examples of discretely forming grooves on an insulator. the

Fig. 6 is a cross-sectional view showing a conventional bus bar connection structure of a battery using an insulator. the

Fig. 7 is a schematic diagram showing problems of conventional insulators. the

8 is a cross-sectional view showing a case where a portion where a side wall of an insulator intersects a bottom surface is formed into an arcuate corner. the

Detailed ways

Hereinafter, embodiments of the present utility model will be described in conjunction with the accompanying drawings. First, with reference to FIGS. 1 to 3 , the connection structure of the conductive strip of the battery to which the insulator of the present invention is applied is illustrated. the

The conductive strip connection structure in this example is a structure in which the conductive strip 3 is electrically connected to the external terminal 2 of the battery installed in a hybrid vehicle (HV) or an electric vehicle (EV), as shown in Fig. 1, which includes an insulator 1. Tighten bolts 4 and nuts 5, etc. As the fastening bolt 4 , a square bolt having a square bolt head 4 a is used here. The insulator 1 is arranged at a predetermined position on the cover 20 . The cover 20 is a cover body for closing an opening of a bottomed cylindrical case main body (not shown). The battery case is composed of a case main body and a cover 20 . The insulator 1 is a member made of an insulating material, and includes a base plate portion 11 and a bolt holding portion 12 provided at one end of the base plate portion 11 as shown in FIG. 2 . the

A fixing piece (not shown) of the external terminal 2 is placed on the top surface (the surface opposite to the surface in contact with the cover 20 ) of the substrate portion 11 . A peripheral wall 11a is integrally formed on the outer periphery of the substrate portion 11, and the peripheral wall 11a can surround the outer peripheral edge of the fixing piece of the external terminal 2 placed on the top surface of the substrate portion 11, and the peripheral wall 11a can secure the external terminal 2. The insulation between the fixed piece and the cover 20. In addition, the substrate portion 11 is provided with a through hole 11b. The through hole 11 b is an insertion hole into which a rivet (not shown) for fixing the insulator 1 and the external terminal 2 to the cover 20 is inserted. the

The bolt holding portion 12 has a side wall 121 capable of surrounding four surfaces of a bolt head (square shape) 4 a of the fastening bolt 4 . The side wall 121 is a wall extending from the bottom 122 (the substrate portion 11 ) of the insulator 1 toward the top side (the side opposite to the cover 20 side). The side wall 121 and the bottom 122 constitute a bolt receiving hole 120 having a substantially square opening. the

Among the four inner surfaces 121a, 121b, 121c, and 121d of the side wall 121, the distances between the two facing surfaces (the distance between the inner surfaces 121a and 121d, and the distance between the inner surfaces 121b and 121c) are respectively processed into This corresponds to the distance between the two bolt heads 4 a of the fastening bolts (square bolts) 4 so that the bolt heads 4 a of the fastening bolts 4 can be inserted into the interior of the side wall 121 , that is, the bolt receiving hole 120 . the

As described above, the external terminal 2 has a fixing piece (not shown) placed on the top surface of the substrate portion 11 of the insulator 1 . The external terminal 2 is provided with a through hole 2 a through which the threaded body 4 b of the fastening bolt 4 is inserted. In addition, a through hole (not shown) is provided in the fixing piece of the external terminal 2 at a position corresponding to the through hole 11 b of the above-mentioned insulator 1 . the

The bus bar 3 is a connecting member for realizing electrical connection between terminals (electrodes) of the battery. The conductive strip 3 can also be used to connect terminals of electrical equipment that outputs the electric energy of the battery to the outside. The conductive strip 3 is provided with a through hole 3 a through which the screw body 4 b of the fastening bolt 4 is inserted. the

Originally, when the nut 5 is tightened to fasten the busbar 3, the bolt head 4a of the fastening bolt 4 will rotate together with the nut 5, but in this structure, the bolt head 4a is surrounded by the side wall 121 of the insulator 1, and the side wall 121 of the insulator 1 The wall 121 prevents the fastening bolt 4 from turning, so the nut 5 can be tightened. the

The insulator 1 in this embodiment is characterized in that, as shown in FIGS. 1 to 3 , the side wall 121 surrounding the bolt head 4 a of the fastening bolt 4 intersects the bottom surface 122 a (the top surface of the bottom 122 ) of the insulator 1 . The junction part (corner part) 123 of the side wall 121 is formed with the groove part 13 recessed in the inner surface 121a-121d of the side wall 121 and the bottom surface 122a. The cross-sectional shape of the groove portion 13 is approximately semicircular. The groove portion 13 is formed continuously over the entire circumference of the junction portion 123 where the side wall 121 intersects the bottom surface 122a. the

By forming such a groove portion 13 , cracks can be prevented from occurring at the intersection portion (corner portion) 123 where the side wall 121 and the bottom surface 122 a intersect, and the contact length of the fastening bolt 4 can be ensured. Hereinafter, this will be described in more detail. the

First, referring to FIG. 6 , a description will be given of a structure in which no groove is formed at the corner where the side wall and the bottom of the insulator intersect. In FIG. 6, except that the groove is not formed at the corner where the side wall 321 of the insulator 301 intersects with the bottom surface 322a (the top surface of the bottom 322), other parts are basically the same as the connection structure of the bus bar in FIG. 1. Therefore, except Except for the insulator 301 , the same symbols as in FIG. 1 are used for other components (the same components as those in FIG. 1 ). the

In the example shown in FIG. 6 (the example of the prior art), also when the nut 4 is tightened, the side wall 321 of the insulator 301 plays a role of preventing the fastening bolt 4 from rotating. However, when the nut 4 is tightened to fasten the bus bar 3, the side wall 321 of the insulator 301 is inclined to the outside due to being squeezed by the bolt head 4a (refer to the locking wire part of FIG. 7), so that the stress is concentrated on the side wall 321 and the The corner (corner top) PC where the bottom surface 322a intersects may cause cracks in the corner PC. the

On the other hand, in the insulator 1 of this embodiment, as shown in FIGS. The inner surfaces 121a to 121d of the side walls 121d and the grooves 13 in the bottom surface 122a can prevent cracks from occurring at the junction (corner) 123 where the side wall 121 and the bottom surface 122a intersect. In addition, since the groove portion 13 of the insulator 1 according to the present embodiment has a cross-sectional shape recessed into the inner surfaces 121 a to 121 d and the bottom surface 122 a of the side wall 121 , the side wall 121 does not shrink toward the inside. Therefore, it is not necessary to cut the bolt head 4a of the fastening bolt 4, and the contact length of the fastening bolt 4 can be ensured. the

Here, as shown in FIG. The shape of the inner surface of the side wall 121 and the inner surface of the bottom surface 122a) may be sufficient. The height difference h (depth of the groove 13 ) between the bottom line La of the groove 13 and the top surface (bottom surface 122 a ) of the bottom 122 is not particularly limited. For example, as shown in FIG. 4(B), the level difference between the bottom line La of the groove 13 and the top surface (bottom surface 122a) of the bottom 122 is small (less than that of the groove 13 in FIG. 4(A)). height difference) cross-sectional groove portion 13b. the

In addition, regarding the cross-sectional shape of the groove, in addition to a shape with a certain curvature such as a semicircle, for example, a cross-section formed by a combination of arbitrary curves as shown in FIG. 4(C) can also be used. The groove portion 13c of the shape, or the groove portion 13d having a cross-sectional shape formed by a plurality of straight lines intersecting at an angle greater than 90 degrees as shown in FIG. 4(D). In addition, the cross-sectional shape of the groove portion may be a shape composed of a combination of a curved line and a straight line. the

In addition, in the above-described embodiment, the groove portion 13 is continuously formed over the entire circumference of the junction portion 123 where the side wall 121 intersects the bottom surface 122a, but the present invention is not limited thereto. The grooves 13 may also be discretely formed on the junction 123 where the side wall 121 intersects the bottom surface 122a. Next, such a configuration will be described with reference to FIGS. 5(A) to 5(D). the

In the example shown in FIG. 5(A), among the four inner surfaces 121a to 121d of the side wall 121, on the junction 123 where the pair of inner surfaces 121b and 121c facing each other in the short-side direction of the insulator 1 intersect with the bottom surface 122a, A groove portion 13 having a substantially semicircular cross-sectional shape is formed. In the example shown in FIG. 5(B), among the four inner surfaces 121a to 121d of the side wall 121, on the junction 123 where the pair of inner surfaces 121a and 121d facing each other in the longitudinal direction of the insulator 1 intersect with the bottom surface 122a, The groove portion 13 having a substantially semicircular cross-sectional shape is formed. In the example shown in FIG. 5(B), the positions of the two grooves 13 in the short-side direction are shifted. In the example shown in FIG. 5(C), four grooves 13 are formed on the junction 123 where the side wall 121 and the bottom surface 122a intersect. on the four corners. In the example shown in FIG. 5(D), a plurality of (seven in FIG. 5(D) ) grooves 13 are discretely and irregularly formed on the junction 123 where the side wall 121 intersects the bottom surface 122a. the

Even with such a structure in which the grooves 13 are discretely formed at the intersection 123 where the side wall 121 and the bottom surface 122a intersect, cracks can be prevented from occurring at the intersection (corner) 123 where the side wall 121 and the bottom surface 122a intersect. , and can ensure the contact length of the bolt. the

In addition, when the grooves are discretely formed in this way, the cross-sectional shapes of the grooves may be those shown in FIG. 4(B), FIG. 4(C), and FIG. 4(D). the

In the above-mentioned embodiment, the example of applying the insulator of the present invention in the structure of using the square bolt as the fastening bolt 4 to connect the conductive strips has been described, but it is not limited thereto. The present invention is also applicable to using a hexagonal Insulators used in structures such as bolts and other fastening bolts with polygonal bolt heads to connect busbars. In this case, the side wall may be provided so as to be able to surround polygonal bolt heads such as hexagonal bolts. In other words, what is necessary is just to make the planar shape of the opening part of a bolt receiving hole a polygon, such as a hexagon. the

In addition, the present invention is also applicable to an insulator used in a structure in which a fastening bolt with an oval bolt head is used to connect busbars. In addition, the present invention is also applicable to an insulator for accommodating nut components such as square nuts or hexagon nuts. the

In the said embodiment, the example which applied this invention to the insulator used for the busbar connection structure of a battery was shown, However, It is not limited to this, This invention can also be applied to the insulator used for other electrical connection structures. the

Claims (1)

1. an insulator, have sidewall and bottom surface be used to surrounding bolt fastener, it is characterized in that:

The junction of intersecting in described sidewall and described bottom surface, be formed with the ditch section be recessed in described side wall inner surface and bottom surface.

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