CN211479792U

CN211479792U - Protective device

Info

Publication number: CN211479792U
Application number: CN202020521326.XU
Authority: CN
Inventors: 唐海浪; 宋东健; 刘树英; 吕继彬
Original assignee: Dongguan Littelfuse Electronic Co Ltd
Current assignee: Dongguan Littelfuse Electronic Co Ltd; Littelfuse Dongguan Manufacturing Facility
Priority date: 2020-04-10
Filing date: 2020-04-10
Publication date: 2020-09-11
Anticipated expiration: 2030-04-10

Abstract

There is provided a protection device comprising a varistor body having a first side opposite a second side, the varistor having an electrodeless free zone extending around a periphery of the varistor body. The protection device may further include a first lead connected to the first side and a second lead connected to the second side. At least one of the first and second leads comprises a first portion and a second portion extending along a first plane, the second portion being in contact with the first side face, and a third portion connected between the first and second portions, the third portion extending away from an electrodeless free area of the varistor body.

Description

Protective device

Technical Field

The present invention relates generally to protecting circuits and electronic circuits and equipment from electrical surges, and more particularly to protecting devices.

Background

Overvoltage protection devices are used to protect electronic circuits and components from damage caused by overvoltage fault conditions. These overvoltage protection devices may include Metal Oxide Varistors (MOVs) connected between circuits to be protected. MOVs have specific current-voltage characteristics that allow them to be used to protect such circuits against catastrophic voltage surges.

Some current MOVs use an additional insulating coating at the edge of the MOV disk to improve the insulating capability. In some cases, larger sized MOVs may be used to obtain better multiple surge performance. However, the increase in product size also increases costs. It is with respect to these and other factors that the present improvements are provided.

SUMMERY OF THE UTILITY MODEL

The MOV of the prior art method includes leads that are coplanar with the first and second major sides of the body of the MOV. This structure causes arcing/flashover along the surface and edges of the disk-like body of the MOV. Embodiments of the present invention provide structures that can be configured to extend in a specific direction away from kinks, bends, curves, etc. of the body, effectively overcoming the above-mentioned deficiencies in prior art methods, thereby providing higher surge voltage capability and multi-pulse surge performance with low cost solutions.

In some embodiments, the protection device may include a varistor body having a first side opposite a second side, the varistor having an electrodeless free region extending around a periphery of the varistor body. The protection device may further include a first lead connected to the first side and a second lead connected to the second side. The first and second leads may comprise first and second portions extending along a first plane, the second portion being in contact with the first or second side, and a third portion connected between the first and second portions, the third portion extending away from an electrodeless free area of the varistor body.

Drawings

The accompanying drawings illustrate exemplary methods of the disclosed embodiments designed so far for practical application of the principles thereof, in which:

fig. 1 is a top view of a protection device according to an embodiment of the present invention; and

fig. 2 is a side view of the protective device of fig. 1 according to the present invention.

The drawings are not necessarily to scale. The drawings are merely representations, not intended to portray specific parameters of the invention. The drawings are intended to depict typical embodiments of the invention, and therefore should not be considered as limiting in scope. In the drawings, like numbering represents like elements.

Moreover, for clarity of illustration, certain elements in some of the figures may be omitted, or illustrated out of scale. Moreover, some reference numerals may be omitted from some of the drawings for clarity.

Detailed Description

Embodiments in accordance with the present invention will now be described more fully hereinafter with reference to the accompanying drawings. Embodiments may be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the systems and methods to those skilled in the art.

Turning now to fig. 1-2, an overvoltage protection device 10 for use with an electrical circuit in accordance with an embodiment of the invention will be described. As shown, the device 10 comprises a varistor body (hereinafter "body") 12, which in this embodiment has a circular or circular shape defined by electrodeless free areas 13 extending around the periphery of the body 12. The body 12 includes a first side 16 opposite a second side 20, wherein the metal electrode 18 may be disposed along the first side 16 and/or the second side 20. First and second leads 21 and 22 (e.g., electrode wires) are electrically connected to the first and

second sides

16 and 20, respectively. In some embodiments, the metal electrode 18 is a metallized layer of ceramic, silver, copper, aluminum, or copper plus aluminum. In some embodiments, the first and second leads 21, 22 are secured to the respective first and

second sides

16, 20 using solder. The varistor body 12 may be directly coupled with the terminal assembly. Although not shown, the device 10 may be wrapped/surrounded by a conformal epoxy or other highly insulating material.

As further shown, at least one of the first and second leads 21, 22 may include a bend or kink formed therein that extends away from the electrodeless free region 13 of the body 12. For example, the first and second leads 21, 22 each include a first portion 31 and a second portion 32 extending along a first plane (e.g., in an x-y plane). As shown, the first and

second portions

31, 32 may be oriented at a non-zero angle "a" relative to each other. The second portion 32 of the first lead 21 may be in contact with the first side 16, and the second portion 32 of the second lead 22 may be in contact with the second side 20. A third portion 33 connected between the first portion 31 and the second portion 32 extends out from the electrodeless free region 13 of the body 12 such that the third portion 33 is not in direct physical contact therewith. In some embodiments, third portion 33 includes a second end 41 opposite first end 42, where first end 41 is connected to first portion 31. Second end 42 may be connected to second portion 32. As shown, the third portion 33 may be configured as a kink, bend, curve, or the like extending generally away from the body 12 in the z-direction. During assembly, an epoxy (not shown) may fill the gap between the first and/or second leads 21, 22 and the body 12 provided by the shape of the third portion 33 during the epoxy coating process. Therefore, the insulating ability between the first and second leads 21, 22 can be improved.

The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Thus, the terms "comprising," "including," or "having," and variations thereof, are open-ended expressions and may be used interchangeably herein.

All directional references (e.g., proximal, distal, upper, lower, upward, downward, left, right, lateral, longitudinal, front, rear, top, bottom, above, below, vertical, horizontal, radial, axial, clockwise, and counterclockwise) are only used for identification purposes to aid the reader's understanding of the present invention, and do not create limitations, particularly as to the position, orientation, or use of the invention. Joinder references (e.g., attached, coupled, connected, and connected) are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. Thus, joinder references do not necessarily infer that two elements are directly connected and in fixed relation to each other.

Further, identifying references (e.g., primary, secondary, first, second, third, fourth, etc.) are not used to denote importance or priority, but rather are used to distinguish one feature from another. The drawings are for illustrative purposes only and the dimensions, positions, order and relative dimensions reflected in the appended drawings may vary.

The scope of the present invention is not limited by the specific embodiments described herein. Indeed, various other embodiments and modifications of the invention in addition to those described herein will become apparent to those skilled in the art from the foregoing description and accompanying drawings. Accordingly, such other embodiments and modifications are intended to fall within the scope of the present invention. Moreover, the present invention is described herein in the context of a particular implementation in a particular environment for a particular purpose. Those skilled in the art will recognize that its usefulness is not limited thereto and that the present invention may be beneficially implemented in any number of environments for any number of purposes. Accordingly, the claims set forth below should be construed in view of the full breath and spirit of the present invention as described herein.

Although the present invention has been described with reference to certain methods, many modifications, alterations and changes to the described methods are possible without departing from the scope and range of the invention as defined in the appended claims. Accordingly, it is intended that the invention not be limited to the described methods, but that it have the full scope defined by the language of the following claims, and equivalents thereof. Although the present invention has been described with reference to certain methods, many modifications, alterations, and changes to the described methods are possible without departing from the spirit and scope of the invention, which is defined in the appended claims. Accordingly, it is intended that the invention not be limited to the described methods, but that it have the full scope defined by the language of the following claims, and equivalents thereof.

Claims

1. A protection device, comprising:

a varistor body having a first side opposite a second side, the varistor having an electrodeless free region extending around a periphery of the varistor body; and

a first lead connected to the first side and a second lead connected to the second side, wherein at least one of the first lead and the second lead comprises:

a first portion and a second portion extending along a first plane, the second portion being in contact with the first side or the second side; and

a third portion connected between the first portion and the second portion, the third portion extending away from the electrodeless free region of the varistor body.

2. The protection device of claim 1, wherein the third portion is not in direct physical contact with the electrodeless free region of the varistor body.

3. The protection device of claim 1, wherein the third portion comprises a second end opposite the first end, wherein the first end is connected with the first portion, and wherein the second end is connected with the second portion.

4. The protection device of claim 3, wherein the second portion is oriented at a non-zero angle relative to the first portion.

5. The protection device of claim 1, wherein the first lead and the second lead are metal conductors.

6. The protection device of claim 1, wherein the varistor body is a Metal Oxide Varistor (MOV) body.