Battery watertight structure and method using insert bolt and nut

Abstract

An invention relating to a battery watertight structure and method for solving problems caused by bushings included in a gasket. According to the present invention, for watertightness in a battery using an insert nut or bolt, the battery watertight structure and method comprises: a lower case (100); an upper case (200) covering the lower case; and a gasket (300) located between the lower case and the upper case, wherein an insert bolt (110) or an insert nut (120) is mounted on the lower case, and assembly hardware (220, 210) corresponding to the insert bolt or insert nut is fastened to the insert bolt or insert nut; and the height of the embedded flange (130) of the insert bolt or insert nut is set such that torque for compressing the gasket is maintained against the axial force when fastening the assembly hardware in the space between the lower case and the upper case; The gasket is characterized by including an inner extension (320) in which the gasket ribs extend in a direction toward the insert bolt or insert nut, so that the gasket expands toward the insert bolt or insert nut as it is compressed between the lower case and the upper case.

Description

Technology Field

[0001] The present invention relates to a battery for an electric vehicle, and specifically, to a technology for improving the watertightness of a battery using an insert bolt / nut. Background Technology

[0002] Gaskets are used for watertight sealing of batteries used in electric vehicles, electric vehicles, and various other fields. FIG. 1a is a schematic diagram of a battery watertight gasket. A gasket (3) is provided between the battery casings (2), and when assembled, the rubber gasket (3) is compressed to block the path of moisture penetration (watertight action).

[0003] However, if only the gasket (3) is used, there is a concern that the gasket (3) may not be firmly fixed and thus the watertightness may be poor. Therefore, multiple metal bushes (1) are combined with the gasket (3) for use.

[0004] FIG. 1b is an example of a bush (1) used in conjunction with a battery watertight gasket. The steel bush (1), fitted into the gasket (3), supports the axial force due to torque when fastening the hardware for assembly. Generally, the shape of the bush (1) is a cylindrical shape with flanges formed on the upper and lower surfaces to fit into the gasket, and a hollow center through which the assembly hardware passes. Prior art literature

[0005] Korean Registered Patent 10-1895870 (September 7, 2018) The problem to be solved

[0006] As described above, a bushing that generates torque is attached to the gasket; however, since the gasket and bushing are not a single integrated unit, the bushing must be manually press-fitted onto the gasket. This increases cycle time and costs, and leads to quality issues as the bushing frequently detaches during the logistics of the gasket. Furthermore, repeatedly tightening and loosening assembly hardware (fastening bolts and nuts) can cause the flange portion of the bushing (the part fixed to the rubber gasket) to bend, resulting in damage to the rubber gasket and permanent deformation. These issues cause torque loosening, and since gasket compression cannot be guaranteed, moisture may enter the battery.

[0007] Therefore, the objective of the present invention is to propose a battery watertight structure to solve these problems. means of solving the problem

[0008] To solve the above problem, according to the battery watertight structure and method comprising: a lower case in which a battery of the present invention is installed; an upper case covering the case; and a gasket located between the lower case and the upper case, an insert bolt or an insert nut is mounted on the lower case, and assembly hardware corresponding to the insert bolt or insert nut is fastened to the insert bolt or insert nut; the height of the embedded flange of the insert bolt or insert nut is set such that a torque for compressing the gasket is maintained against the axial force when fastening the assembly hardware in the space between the lower case and the upper case; and the gasket includes an inner extension portion in which the gasket ribs extend in a direction toward the insert bolt or insert nut, so that as the gasket is compressed between the lower case and the upper case, it expands toward the insert bolt or insert nut.

[0009] The structure and operation of the present invention will become clearer through specific embodiments described later together with the drawings. Effects of the invention

[0010] Since bushings are not used in the gasket, the joining process between the gasket and the bushing is eliminated, reducing cycle time and costs, and resolving the issue of defects occurring during the logistics of the gasket.

[0011] In addition, since the bushing is removed from the gasket, damage or deformation of the gasket does not occur even when the assembly hardware (fastening bolts, fastening nuts) is tightened and loosened multiple times, thereby strengthening the gasket's compression and effectively blocking moisture from entering the battery. Brief explanation of the drawing

[0012] Figure 1a is a schematic diagram of a battery watertight gasket. FIG. 1b is an example of a bushing used in conjunction with a gasket. FIG. 2 is an exploded view of a conventional battery system assembly (BSA) for electric vehicles before the battery watertight structure of the present invention is applied. FIG. 3 is a detailed view of an insert bolt (11) and an insert nut (12) inserted into a lower case (10). Figure 4 shows a bush (31) fitted into a gasket (30). FIG. 5 is a detailed cross-sectional view of the components of FIG. 2 to FIG. 4 assembled. FIG. 6 is a cross-sectional view showing the battery watertight structure of the present invention, which improves upon the conventional gasket / bush-based battery watertight structure. FIG. 7 is a cross-sectional view showing a battery watertight structure when an insert nut (120) is inserted into a lower case (100). Specific details for implementing the invention

[0013] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the preferred embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments described below but may be implemented in various other forms. The embodiments are provided merely to fully disclose the present invention and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined by the contents of the claims. Furthermore, the terms used in this specification are for describing the embodiments and are not intended to limit the present invention. In this specification, the singular form includes the plural form unless specifically stated otherwise. Also, the terms used in this specification, such as 'comprise,' 'comprising,' etc., are used in the sense that they do not exclude the presence or addition of one or more other components, steps, actions, and / or elements other than those mentioned.

[0014] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the embodiments, specific descriptions of related known components or functions are omitted if such detailed descriptions could obscure the essence of the present invention.

[0016] FIG. 2 is an exploded view of a conventional battery system assembly (BSA) for electric vehicles before the battery watertight structure of the present invention is applied.

[0017] A battery is installed in the space of a lower case (10) (made of synthetic resin material) and an upper case (20) (made of metal or synthetic resin material) is placed over it. Before fixing the upper case (20) to the lower case (10), a rubber gasket (30) is placed between the upper case (20), and fastening bolts (21) and / or fastening nuts (22), which are assembly hardware, are fastened through through holes formed in the upper case (20). A plurality of insert bolts (11) and / or insert nuts (12) are insert-molded around the lower case (10) to fasten these assembly hardware (21). In addition, a steel bush (see FIG. 4) is fitted into the gasket (30) at each location where the fastening bolt (21) or insert bolt (11) passes to form the axial force required for torque fastening.

[0019] FIG. 3 is a detailed view of an insert bolt (11) and an insert nut (12) inserted into a lower case (10). When assembling the upper case (20) to the lower case (10), fastening bolts (21) and fastening nuts (22), which are assembly hardware, are fastened to the insert bolts (11) and insert nuts (12), respectively. In the embodiment of FIG. 2, both the insert bolt (11) and the insert nut (12) are used in a single BSA, but this is not limited thereto.

[0021] FIG. 4 shows a bush (31) fitted into a gasket (30). A hole (a hole for passing fastening bolt (21) and insert bolt (11)) formed in a rubber gasket (30) is opened by elastic force, and a hollow cylindrical steel bush (31) with flanges on its upper and lower surfaces, as shown in FIG. 1b, is press-fitted into it to join them.

[0023] FIG. 5 is a detailed cross-sectional view of the assembled components described above. An insert bolt (11) is insert-molded into the lower case (10) of the BSA, and a bush (31) is fitted into the gasket (30). Accordingly, the upper part of the gasket (30) contacts the lower surface of the upper case (20) above, and the lower part of the gasket (30) contacts the upper surface of the lower case (10) of the BSA below, thereby providing a watertight seal.

[0024] Here, the upper flange portion of the bush (31) contacts the lower surface of the upper case (20) above, and the lower flange portion of the bush (31) contacts the embedded flange (13) of the insert bolt (11) below. Therefore, as mentioned in the 'problem to be solved' above, as the fastening of the fastening nut (22) and the insert bolt (11) is repeated several times, the flange portion of the bush (31) may bend or deform, and the gasket (30) may be damaged or permanently deformed. Consequently, loosening of the torque of the fastening portion of the fastening nut (22) and the insert bolt (11) is induced ('A' indicated portion), and since gasket compression is not guaranteed, moisture may enter the battery ('B' indicated portion).

[0026] FIG. 6 is a cross-sectional view showing the battery watertight structure of the present invention, which improves upon the conventional gasket / bush-based battery watertight structure described above.

[0027] Similar to the structure of Fig. 5, an insert bolt (110) is inserted into the lower case (100) of the BSA, and a gasket (300) is fitted between the lower case (100) and the upper case (200). Then, a fastening nut (220), which is assembly hardware, is fitted onto the insert bolt (110) protruding through the through hole of the upper case (200) and the gasket (300) to fasten the components (gasket (300), lower case (100), upper case (200)).

[0028] However, in the present invention, the gasket (300) does not have a bush. Instead, the thickness (height) of the embedded flange (130) of the insert bolt (110) is extended to correspond to the position where the existing bush was located between the lower case (100) and the upper case (200). As a result, the problem of deformation of the bush's flange portion when fastening assembly hardware due to the relatively weak flange structure of the bush is overcome, and the insert bolt (110) can withstand (counter) the axial force when fastening assembly hardware (i.e., fastening nut (220)) instead of the bush, thereby maintaining the torque for compressing the gasket.

[0029] In addition, an inner extension (320) is added so that the gasket material goes further into the inner side of the through hole of the gasket (300) to surround the embedded flange (130) of the insert bolt (110). The maximum thickness of the gasket is greater than the thickness of the embedded flange, and the thickness of the inner extension is formed to be smaller than the thickness of the embedded flange. The inner extension is spaced apart from the embedded flange, and as the gasket (300) is compressed between the lower case (100) and the upper case (200), the inner extension (320) enters further into the through hole and expands so that it can approach or come into close contact with the side of the embedded flange (130) of the insert bolt (110). And since there is no bushing in the gasket (300), the watertightness between the lower case (100) and the upper case (200) is maintained entirely by the compression of the gasket (300), thereby blocking moisture from penetrating into the space between them ('C' marked section) ('D' marked section).

[0031] FIG. 7 is a cross-sectional view showing a battery watertight structure in which an insert nut (120) is inserted into the lower case (100) instead of an insert bolt (110), unlike the structure of FIG. 6.

[0032] An insert nut (120) is inserted into the lower case (100) of the BSA, and a gasket (300) is fitted between the lower case (100) and the upper case (200). A fastening bolt (210), which is assembly hardware, passes through the through hole of the upper case (200) and the gasket (300) and is fitted into the insert nut (120) to fasten the components (gasket (300), lower case (100), upper case (200)). The watertight action of the gasket (300) and the improvement of its effect are the same as in the case of the insert bolt (110) of FIG. 6.

[0034] Although the present invention has been described in detail through preferred embodiments thereof, those skilled in the art will understand that the present invention may be implemented in a specific form different from that disclosed herein without changing its technical concept or essential features.

[0035] As such, the embodiments described above should be understood as illustrative in all respects and not restrictive. Furthermore, the scope of protection of the present invention is determined by the claims set forth below rather than by the detailed description above, and all modifications or variations derived from the claims and their equivalents should be interpreted as being included within the technical scope of the present invention.

Claims

Claim 1 A battery watertight structure comprising: a lower case in which a battery is installed; an upper case covering the lower case; and a gasket located between the lower case and the upper case, wherein an insert bolt is mounted on the lower case and protrudes through the gasket and the upper case, and assembly hardware corresponding to the insert bolt is fastened to the insert bolt, and the height of the embedded flange of the insert bolt is set such that torque for compressing the gasket is maintained against the axial force when fastening the assembly hardware in the space between the lower case and the upper case, and includes an inner extension portion in which the gasket rib extends into the inner side of the through hole of the gasket, wherein the maximum thickness of the gasket is greater than the thickness of the embedded flange, and the thickness of the inner extension portion is formed to be smaller than the thickness of the embedded flange, and the inner extension portion is spaced apart from the embedded flange and expands toward the insert bolt as it is compressed between the lower case and the upper case. Claim 2 A battery watertight structure comprising: a lower case in which a battery is installed; an upper case covering the lower case; and a gasket located between the lower case and the upper case, wherein an insert nut is mounted on the lower case, and assembly hardware corresponding to the insert nut penetrates the upper case, the gasket, and the lower case and is fastened to the insert nut, wherein the height of the embedded flange of the insert nut is set such that torque for compressing the gasket is maintained against the axial force when fastening the assembly hardware in the space between the lower case and the upper case, and the gasket includes an inner extension portion in which the gasket rib extends into the inner side of the through hole of the gasket, wherein the maximum thickness of the gasket is greater than the thickness of the embedded flange, and the thickness of the inner extension portion is formed to be smaller than the thickness of the embedded flange, and the inner extension portion is spaced apart from the embedded flange and expands toward the insert nut as the gasket is compressed between the lower case and the upper case. Claim 3 A battery watertight structure according to claim 1 or 2, characterized in that the lower case is made of a synthetic resin material. Claim 4 A battery watertight structure according to claim 1 or 2, wherein the upper case is made of one of synthetic resin and steel. Claim 5 A lower case in which a battery is installed; an upper case covering the lower case; A method for watertightening a battery, comprising a gasket located between the lower case and the upper case, wherein an insert bolt is mounted on the lower case and protrudes through the gasket and the upper case, and assembly hardware corresponding to the insert bolt penetrates the upper case, the gasket, and the lower case and is fastened to the insert bolt; wherein the height of the embedded flange of the insert bolt is set such that a torque for compressing the gasket is maintained against the axial force when fastening the assembly hardware in the space between the lower case and the upper case; wherein the gasket extends its ribs inwardly into the through hole of the gasket to form an inner extension, such that the maximum thickness of the gasket is greater than the thickness of the embedded flange, and the thickness of the inner extension is formed to be smaller than the thickness of the embedded flange, and the inner extension is spaced apart from the embedded flange and expands toward the insert bolt as the gasket is compressed between the lower case and the upper case. Claim 6 A method for watertightening a battery, comprising: a lower case in which a battery is installed; an upper case covering the lower case; and a gasket located between the lower case and the upper case, wherein an insert nut is mounted on the lower case, and assembly hardware corresponding to the insert nut penetrates the upper case, the gasket, and the lower case and is fastened to the insert nut to watertighten the battery, wherein the height of the embedded flange of the insert nut is set such that a torque for compressing the gasket is maintained against the axial force when fastening the assembly hardware in the space between the lower case and the upper case; wherein the gasket extends its ribs inwardly into the through hole of the gasket to form an inner extension, such that the maximum thickness of the gasket is greater than the thickness of the embedded flange, and the thickness of the inner extension is formed to be smaller than the thickness of the embedded flange, and the inner extension is spaced apart from the embedded flange and expands toward the insert nut as the gasket is compressed between the lower case and the upper case. Claim 7 A battery watertight method according to claim 5 or 6, characterized in that the lower case is made of a synthetic resin material. Claim 8 A battery watertight method according to claim 5 or 6, characterized in that the lower case is made of one of synthetic resin and steel.

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