1. Field of the Invention
The present invention relates to switches and, more particularly, to a trigger switch.
2. Description of Related Art
Trigger switches are typically used in electrical devices to turn on and power the devices. Typically, trigger switches protrude from or are flush with front bezels of electrical devices. As a result, the trigger switches may be easily pushed inadvertently. What is desired, therefore, is to provide a trigger switch for preventing unintentional triggering.
Referring to
The pressing element 10 includes a cylindrical pressing portion 12 having a first end and a second end, two rectangular attracting portions 14 extending perpendicularly from opposite sides of the second end of the pressing portion 12, and a cylindrical trigger portion 16 extending from the second end of the pressing portion 12.
The first locating element includes two magnets 20 positioned on an inner surface of a bezel 100 of an electrical device and located at opposite sides of a through hole defined in the bezel 100.
In the illustrated embodiment, the second locating element includes two L-shaped elastic members 30. Each elastic member 30 includes a fixing part (not labeled) fixed to the inner surface of the bezel 100 and a flexible part 32 extending perpendicularly from an end of the fixing part.
The first end of the pressing portion 12 passes through the magnets 20 and the through hole of the bezel 100, to extend out from the bezel 100. The attracting portions 14 of the pressing element 10 are attracted by and engage with the magnets 20. The attracting portions each have a magnet contacting surface configured to contact the magnets and an opposite switch facing surface. A distal end of the trigger portion 16 faces a trigger element 40 of a circuit board 50 of the electrical device. When the pressing element 10 is fully depressed, the distal end of the trigger portion 16 contacts and applies a force to the trigger element 40, and a switching circuit connected to the trigger element 40 is triggered. The flexible part 32 of each elastic member 30 is positioned opposite a corresponding magnet 20 and facing a corresponding attracting portion 14.
In an initial state, when the pressing element 10 is not depressed, a distance between the first end of the pressing portion 12 and the outer surface of the bezel 100 is “N”. A distance between the flexible part 32 of each elastic member 30 and each of the switch facing surfaces is “L”. A distance between the distal end of the trigger portion 16 and the trigger element 40 is “M”. The distances M, L, and N satisfy the following formula: L≦M≦N.
In another embodiment, the second locating element 30 includes two springs (now shown) positioned on the circuit board 50 and located opposite the trigger element 40 to limit movement of the pressing element 10.
It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the embodiment, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Number | Date | Country | Kind |
---|---|---|---|
200810303230.X | Jul 2008 | CN | national |