Patent Application
20050161311
1. Field of the Invention
This invention pertains to a control knob, particularly a control knob with a multi-color indicator which varies in color by way of a multi-color LED which varies in color in accordance with the electrical signal level being controlled by the control knob. The electrical signal level is typically used to control an audio output, but other outputs can be likewise controlled.
2. Description of the Prior Art
In the prior art, the use of control knobs to vary a signal, particularly an electrical signal which is used to control an audio output, is well known. However, as the number of control knobs on a control panel increases, and as faster and more intuitive responses are required from the human operator for many applications, the human operator may have difficulties in fully comprehending and processing the various control levels and the changes which may need to be made.
It is therefore an object of the present invention to provide a control knob for a signal, particularly an electrical signal which is used to control an audio output, which provides immediate, intuitive visual feedback as to the level of the electrical signal.
It is therefore a further object of the present invention to provide a control knob which provides visual feedback, but does not require extensive hardware changes to a control panel.
It is therefore a still further object of the present invention to provide a control knob which provides visual feedback, with little or no programming required from the user.
It is therefore a still further object of the present invention to provide a control knob which is simple and inexpensive to manufacture.
These and other objects are attained by providing a control knob with a clear or translucent pointer portion, wherein the control knob is placed over a multi-color LED which provides light output which passes through the clear or translucent pointer portion. The color of the light emanating from the multi-color LED is varied in accordance with the output level of the electrical control signal which is controlled by the knob. Therefore, in the case of a dual color LED, a relatively high level of electrical control signal will result in a first color being passed through the clear or translucent pointer portion while a relatively low level of electrical control signal will result in a second color being passed through the clear or translucent pointer portion. In the case of a three color LED, then yet another color is passed through the clear or translucent pointer portion in response to a relatively intermediate level of electrical control signal.
Further objects and advantages of the invention will become apparent from the following description and from the accompanying drawings, wherein:
FIG. 1 is an exploded view of the control knob of the present invention.
FIG. 2 is a perspective view of the control knob of the present invention on a control panel.
FIG. 3 is a schematic of the circuitry associated with the multi-color LED of the control knob of the present invention.
Referring now to the drawings in detail wherein like numerals refer to like elements throughout the several views, one sees that FIG. 1 is an exploded view of control knob 10, while FIG. 2 shows the control knob 10 on a control panel 100.
Control knob 10 is hollow and is typically essentially rotationally symmetric. However, different applications may require differently shaped control knobs 10. Control knob 10 includes a radial section 12 of clear or translucent plastic for the passage or channeling of light. Radial section 12 further typically serves as a pointer to indicia (not shown) on control panel 100. The clear or translucent control shaft 14 of potentiometer 16 passes through aperture 101 of control panel 100 and is secured to control knob 10 so that control shaft 14 rotates in concert with control knob 10. The position of control knob 10 controls the resistance of potentiometer 16 so as to control the level of the underlying signal. For instance, the “off” position of control knob 10 may position radial section 12 at about the seven or eight o'clock position. The underlying electrical signal is typically switched “off” at this position. As the control knob 10 is rotated clockwise to a maximum “on” position so that radial section 12 is at about the four or five o'clock position, the underlying electrical signal is increased by way of the reduction of resistance of potentiometer 16. Multiple color LED (light emitting diode) 18 extends into clear control shaft 14 of potentiometer 16. Multiple color LED 18 emits one of a multiple (typically two or three) of colors dependent upon the voltage across terminals 20, 22 of LED 18. Terminals 20, 22 are affixed to control board 30. Control board 30 includes the circuitry of FIG. 3 so that the input signal 24 which is controlled by the rotational position of potentiometer 16 controls the voltage across terminals 20, 22 of LED 18. As the voltage level increases past a threshold, the color output of LED 18 changes from a first color to a second color. If multi-color LED 18 can emit more than two colors, then a different color will be emitted as the voltage level passes through an intermediate range. The light emitted from LED 18 is passed through clear control shaft 14 of potentiometer 16 and then through radial section 12 thereby allowing the user to view the color of the LED 18. This provides a visual indication to the user as to the level of the underlying signal being controlled by control knob 10.
Thus the several aforementioned objects and advantages are most effectively attained. Although preferred embodiments of the invention have been disclosed and described in detail herein, it should be understood that this invention is in no sense limited thereby and its scope is to be determined by that of the appended claims.
