Patent ID: 8941435
Filing Date: 2015-01-27
Classification: H03K

Abstract:
1. A control panel comprising a plurality of touch switches and a control unit, each touch switch of the plurality of touch switches comprising: operating portions that are subject to touch operations by a conductive body, electrodes disposed proximate of the operating portions, light-emitting elements that light up the operating portions, a first brightness adjusting unit that performs brightness adjustment of the light-emitting elements through PWM (pulse width modulation) control, and a detecting circuit that outputs a detected value in accordance with electrostatic capacitances of the electrodes, a part of the plurality of touch switches further comprising: light-emitting elements for indicators representing states of functions allotted to the operating portions through lighting states, and a second brightness adjusting unit that performs brightness adjustment of the light-emitting elements for indicators through PWM control, the control unit comprising: a memory device that stores reference values for each of the plurality of touch switches, a judging unit that judges for each of the plurality of touch switches that a touch operation has been made for a corresponding touch switch when a difference between a detected value detected by the detecting circuit that the corresponding touch switch comprises and a reference value for the corresponding touch switch that is stored in the memory device is not less than a prescribed value, and a reference value updating unit that stores a detected value, which is the first value detected by the detecting circuit after transition of the executing state of the PWM control by the first brightness adjusting unit, or a detected value, which is the first value detected by the detecting circuit, which is comprised by a touch switch that is in a specified positional relationship with respect to the touch switch which executing state of PWM control by the second brightness adjusting unit has changed, after transition of the executing state of the PWM control by the second brightness adjusting unit, in the memory device as the reference value for the touch switch comprising the detecting circuit.