1. Field of Invention
The present invention relates to an electric current overload protection device, and more particular to a protection device that is also capable of detecting and preventing circuit failure due to high temperature.
2. Description of the Related Art
With reference to
Although the aforementioned overload protection device may provide the circuit loop with the high temperature and overload current protection, the overload protection device still has disadvantages. For instance, an installation angle of the overload protection device is limited since the knife-break switch cannot function up side down. Moreover, many elements are required in the overload protection device, thus manufacturing complexity and costs are not satisfactory.
The present invention provides a current and temperature overload protection device that has a simplified structure without limitation to installation orientation.
The primary objective of the present invention is to provide a current and temperature overload protection device that is simple to manufacture without limitation to installation orientation.
The current and temperature overload protection device has a brace, a thermal sensing contact, a solder layer, two ports and two resilient elements. The thermal sensing contact, the solder layer, the two ports and the two resilient elements are respectively mounted on the brace, where each resilient element is bent to connect between one of the ports and the thermal solder layer. The current and temperature overload protection device is mounted on a circuit board to connect with a circuit loop of the circuit board, and the thermal sensing contact is connected to a heat-generating device. Therefore, the current and temperature overload protection device provides protections to the circuit loop from thermal and current overloads.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
With reference to
The thermal sensing contact (20) is thermally conductive and is mounted on the top and bottom surface of the brace (10). The thermal sensing contact (20) may be mounted through the brace (10), thereby contacting the top and bottom surfaces of the brace (10), or may be a band-like thermally conductive material that is mounted around the brace (10).
The solder layer (25) is sheet like, is electrically conductive, is low temperature melting and is mounted on the thermal sensing contact (20) corresponding to the top surface of the brace (10). The solder layer (25) may be Tin or Tin-alloy, which has a relatively low melting temperature at around 250 to 400 degrees centigrade.
The two ports (30) are electrically conductive, are mounted on the top and bottom surfaces of the brace (10) and are separated from the thermal sensing contact (20).
The two resilient elements (40) are electrically conductive, are rod-like, maybe made of stainless steel, copper, copper-alloy or the like and each resilient element (40) has two ends. The resilient elements (40) are bent and the ends of the resilient elements (40) are respectively mounted on and electrically connected to the solder layer (25) and respective ports (30). Thus, the ports (30) are electrically connected to each other by the resilient elements (40) and the solder layer (25). When the solder layer (25) melts, one end of each resilient element (40) is released from the solder layer (25) so the resilient elements (40) extend and disconnect the two ports (30).
The cover (60) is non-conductive, is shaped corresponding to the brace (10) and covers the top surface of the brace (10) to protect elements on the top layer of the brace (10).
As described above, the disclosed current and temperature overload protection device is a kind of a surface mount device (SMD). Therefore, the ports (30) on the bottom surface of the brace (10) may be mounted on a circuit board so as to be connected with a circuit loop in the circuit board. With reference to
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
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Number | Date | Country | |
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20100328017 A1 | Dec 2010 | US |