Original Publication Date: 1997-Jan-01
Included in the Prior Art Database: 2005-Apr-01
Taylor, LG: AUTHOR [+1]
A typical manufacturer of electrical/electronic goods produces a very wide range of products in various shapes and sizes. Most of these products have a power switch of some sort located somewhere on the product casing.
manufacturer of electrical/electronic goods produces
a very wide range of products in various shapes and sizes. Most of
these products have a power switch of some sort located somewhere on
the product casing.
with this state of affairs is that there is very
little commonality between different products regarding the position
of the power switch. This can create problems for users who are
never certain where they should look first to find the switch.
solution uses the manufacturer's trademark, or
logo, which is usually prominently placed on the product, to locate
the power switch.
switch itself may be operated in a number of
ways. If the switch is actually used to interrupt the mains
electricity going into a product, the logo could be placed on a panel
which acts directly on a switch, or through a pushrod, or the logo
could even form the front face of a rocker switch.
product is one of the increasing number where the power
switch is not used to interrupt mains electricity, such as portable
PC's and monitors where the microcontroller is run constantly,
another type of switch could be used. Where this is the case, the
normal microswitch could be attached to the logo. An alternative,
where the logo includes a number of separate elements as in the
'bar' version of the trademark 'IBM', is to use a touch sensitive
switch formed by the 'bars'.
illustrates a possible implementation for a computer
monitor. In this circuit, diagram Cs represents the capacitance of
the bars in the IBM Logo. Alternate bars in the Logo would be
connected to either ground or the 5v rail through R1. Rf represents
the resistance of a finger touching the Logo. When a touch is made,
Rf discharges C and the voltage on the gate of Q1 reduces. When the
voltage on the gate has dropped by the threshold vo...