Illuminated knob assembly

The control knob engages, on its interior, a translucent polycarbonate jewel body collar assembly of a first color, such as white, which, in turn, provides a housing for a translucent polycarbonate jewel light pipe assembly of a second color, such as blue or blue-green. The jewel body collar assembly includes a collar to engage the interior cylindrical support section of the control knob and a light pipe housing assembly to engage the jewel light pipe assembly. The jewel body collar assembly further includes a ridge which protrudes through a slot in the sidewall and front face of the control knob thereby forming an indicator for the control knob. In ambient illumination, such as during the day, the indicator appears to be the color of the jewel body collar assembly, such as white. However, when the dashboard is electrically illuminated, such as during the night, the illumination is collected by the jewel light pipe assembly, and the color of the jewel light pipe assembly, such as blue or blue-green, is projected through the ridge of the jewel body collar assembly and the indicator appears to be blue or blue-green.

BACKGROUND OF INVENTION 
1. Field of Invention 
This invention pertains to a control knob, particularly for automotive 
applications, with an indicator portion which remains a first preselected 
color, such as white, during the day, but which appears illuminated at 
night to a second preselected color, such as blue. Additionally, a collar 
assembly of the first preselected color within the control knob supports a 
light pipe assembly of the second preselected color and provides a bearing 
surface against the mating bezel. 
2. Description of the Prior Art 
In the prior art, control knobs, particularly control knobs in automotive 
applications, have had position indicators for indicating the rotational 
position of the knob. While paints and inks have frequently been used to 
provide such an indicator, this solution has not been resistant to 
abrasion. U.S. Pat. No. 5,450,653 entitled "Composite Knob with an 
Insertable Position Indicator" issued on Sep. 19, 1995 to Howie, Jr. 
discloses a composite knob with an insertable position indicator which 
would be more resistant to abrasion than simple paints or inks. The 
position indicator has a color contrasting to that of the knob. However, 
this indicator does not provide a first color, such as white, during the 
daytime, and a second distinct color, such as blue, during the nighttime. 
U.S. Pat. No. 5,050,269 entitled "control Knob" issued on Sep. 24, 1991 to 
Engstrom et al. discloses a control knob, apparently for a portable 
telephone or "walky-talky" type device with an outer portion of reduced 
hardness molded over an inner portion with a blade portion extending 
through the outer portion to provide an indicator. This does not appear to 
provide for different colors of the indicator during daytime and 
nighttime. 
U.S. Pat. No. 5,518,561 entitled "True Color Day-Night Graphics and Method 
of Assembly issued on May 21, 1996 to Rosa discloses a display panel with 
a light-emitting electroluminescent portion, but does not relate to 
control knobs, particularly for automotive applications. 
Additionally, in the prior art, it has been a substantial concern that the 
knobs not wobble in use, as this may be disconcerting to the user. 
Other references of interest include U.S. Pat. No. 5,469,758 issued on Nov. 
28, 1995 to Howie, Jr.; U.S. Pat. No. 5,259,267 issued on Nov. 9, 1993 to 
Jurewicz; U.S. Pat. No. 5,303,612 issued on Apr. 19, 1994 to Odom et al. ; 
U.S. Pat. No. 2,753,911 issued on Jul. 10, 1956 to Haslett; and U.S. Pat. 
No. 273,685 issued on Mar. 6, 1883 to Huntley. 
Additionally, U.S. patent application Ser. No. 08/746,989 entitled "Control 
Knob" was filed on Nov. 19, 1996 on behalf of the present assignee. 
OBJECTS AND SUMMARY OF THE INVENTION 
It is therefore an object of this invention to provide a reliable indicator 
for a control knob, particularly for automotive applications. 
It is therefore a further object of this invention to provide an indicator 
for a control knob, the indicator being a first color, such as white, 
during the day, and a second color, such as blue, during the night when 
illuminated. 
It is therefore a further object of this invention to provide an indicator 
for a control knob, particularly for automotive applications, which is 
simple and inexpensive to construct and install. 
It is therefore a further object of this invention to provide a control 
knob, particularly for automotive applications, with reduced side-to-side 
wobble. 
These and other objects are attained by a control knob which includes a 
jewel body collar assembly into which a jewel light pipe assembly is 
inserted. The jewel body collar assembly includes a portion which extends 
or protrudes through a slot in the cylindrical sidewalls of the control 
and in a portion of the front of the control knob to form the indicator. 
Additionally, the jewel body collar assembly includes a cylindrical collar 
which engages the interior cylindrical portion of the knob which engages 
the carrier shaft thereby forming a bearing surface against the mating 
bezel thereby reducing side-to-side wobble of the knob during use. As the 
jewel body collar assembly is made of a lubricated material, such as 
acetel, this provides lubrication for the rotation of the control knob. 
Snap fit engagements provide for ease of assembly. The jewel body collar 
assembly is translucent, typically white, so that the indicator appears 
white during daytime. However, the jewel light pipe assembly is 
translucent and of a second color, such as blue or "ice blue", so that 
when the knob is illuminated from behind, such as the nighttime, when the 
dashboard is electrically illuminated, part of this light is transmitted 
through the jewel light pipe assembly and out the jewel body collar 
assembly so that the indicator appears as a blue color.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
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 
rear view of the control knob 10, jewel light pipe assembly 12 and jewel 
body collar assembly 14 of the present invention. As shown in FIGS. 1 and 
2, the control knob 10 includes a cylindrical shell 16 with undulations 18 
spaced about the periphery thereof. Undulations 18 allow the user to grasp 
firmly and rotate control knob 10. 
As shown in FIGS. 2 and 5, control knob 10 further includes slightly convex 
front circular face 20 which includes slot 24 extending radially inwardly 
from the "twelve-o'clock" position, terminating in an indented spherical 
dimple 22. As further shown in FIGS. 1 and 2, slot 24 is further formed 
longitudinally along a portion of cylindrical shell 16 at the "twelve 
o'clock" position and through a portion in which an undulation 18 would 
otherwise be formed. The interior portion of cylindrical shell 16 at the 
"twelve o'clock position" (which includes slot 24) includes notch 25 
formed by a reduction in thickness of cylindrical shell 16. Similarly, the 
interior portion of front circular face 20 at the "twelve o'clock 
position" (which includes slot 24) includes a reduction of thickness, as 
will be explained hereinafter, to provide a detent mechanism to engage 
jewel body collar assembly 14. 
The outer circumferential edge of front circular face 20 is chamfered 
inwardly in order to present an edge 26 which is free of sharp surfaces 
and to present a clean aesthetic appearance. 
As shown in FIGS. 3 and 5, the center of the rear control knob 10 includes 
a D-shaped aperture 28 comprised of a partially circular portion 30 and a 
flat portion 32 for engaging a carrier shaft 100 (shown in phantom in FIG. 
1) of a similar cross section formed concentrically within cylindrical 
support portion 38 formed about the axis of rotation of knob 10. FIG. 3 
shows the use of to engage control shaft 100. However, the use of could be 
eliminated with the method of attachment disclosed in pending 
commonly-assigned U.S. application Ser. No. 08/746,989 entitled "Control 
Knob" filed on Nov. 19, 1996, now U.S. Pat. No. 5,857,242, the disclosure 
of which is incorporated herein by reference. Similarly, the disclosure of 
the parent application, Ser. No. 08/812,576, filed on Mar. 7, 1997, now 
U.S. Pat. No. 5,752,759 is incorporated herein by reference. 
Supporting ribs 36 extend from the interior of cylindrical shell 16 to the 
exterior of the walls forming D-shaped aperture 28. 
As shown in FIG. 3 and more detail in FIG. 4, notch 40 is formed within 
cylindrical support portion 38 abutting flat portion 32, radially opposed 
from notch 25 on the interior of cylindrical shell 16 thereby forming a 
detent engagement for jewel body collar assembly 14. 
While the jewel light pipe assembly 12 and jewel body collar assembly 14 
are illustrated as separate elements, these elements could be formed 
together as one piece in an insert molding process. 
Jewel body collar assembly 14 is illustrated in FIGS. 6a-6e. Jewel body 
collar assembly 14 includes a cylindrical collar 50 with a light pipe 
housing assembly 52 fixed along a portion of the circumference thereof. As 
shown in FIGS. 1 and 3, cylindrical collar 50 joins concentrically around 
cylindrical support section 38 of knob 10 so as to form a bearing surface 
against the mating bezel (not shown) thereby reducing or eliminating 
side-to-side wobble of knob 10 during use. Further, as the jewel body 
collar assembly 14 is typically made of a lubricated material, such as 
acetel, ease of rotation of knob 10 is improved. 
Light pipe housing assembly 52 further presents angled surface 51 to add 
relief during assembly until jewel body collar assembly 14 locks into 
place in control knob 10. This locking or snap fit procedure is described 
in further detail hereinafter. 
The proximal portion of light pipe housing assembly 52 extends inwardly 
radially from a circumference of cylindrical collar 50 to be engaged by 
notch 40 of cylindrical support portion 38 of knob 10, as shown in FIGS. 
1, 3 and 4 while the distal portion of light pipe housing assembly 52 
extends generally diagonally upwardly and outwardly to indicator element 
53. Indicator element 53 includes interior grooved section 54 and exterior 
ridged section 55, further including horizontal section 56 and vertical 
section 57 (from the perspective of FIGS. 6a and 6c), both of which are 
intended to be visible from the exterior of knob 10. Horizontal section 56 
of exterior ridged section 55 of indicator element 53 engages the portion 
of slot 24 on cylindrical shell 16 while vertical section 57 of exterior 
ridged section 55 of indicator element 53 engages the portion of slot 24 
on front circular face 20 (see FIGS. 1 and 2). 
Additionally, the proximal portion of light pipe housing assembly 52 
includes blind longitudinal slots 60 for engaging jewel light pipe 
assembly 12. 
Jewel body collar assembly 14 is typically polycarbonate, such as acetel, 
translucent, and of a first preselected color, typically white. Therefore, 
when jewel light pipe assembly 12 is not illuminated from the dashboard or 
control panel (not shown), the jewel body collar assembly 14 appears to be 
white. However, when jewel light pipe assembly 12 is illuminated from the 
dashboard or control panel, the color of the jewel light pipe assembly 12 
(the second preselected color, such as blue, blue-green, or "ice blue") is 
projected through the jewel body collar assembly 14 and the color of the 
jewel light pipe assembly 12 on the jewel body collar assembly 14. 
Jewel light pipe assembly 12 is shown in more detail in FIGS. 7a, 7b, 7c 
and 7d. Jewel light pipe assembly 12 includes tail 70 which gathers light 
from the illuminated dashboard (not shown) or similar control board from 
which the control shaft 100 extends. The light is directed upwardly from 
tail 70 into body 72 of jewel light pipe assembly 12. Tail 70 includes 
longitudinal protrusions 74 (a cross section of which is shown in FIG. 7d) 
which engage blind longitudinal slots 60 in jewel body collar assembly 14. 
Tail 70 further includes upwardly extending catch 76 to allow the simple 
manual removal of jewel light pipe assembly 12 from jewel body collar 
assembly 14. Jewel light pipe assembly 12 is translucent polycarbonate and 
is of a second preselected color, such as blue, blue-green or "ice blue", 
which is to be the color of the indicator of control knob 10 during 
nighttime when the illumination is from the dashboard (not shown) or 
similar control board. The upper portion of body 72 includes indicator 
ridge 78 which includes horizontal ridge 80 and vertical ridge 82 (from 
the perspective of FIG. 7a). Horizontal ridge 80 of jewel light pipe 
assembly 12 engages horizontal section 56 of interior grooved section 54 
of jewel body collar assembly 14. Likewise, vertical ridge 82 of jewel 
light pipe assembly 12 engages vertical section 57 of interior grooved 
section 54 of jewel body collar assembly 14 (see FIG. 1). 
To install the control knob 10, jewel light pipe assembly 12 and jewel body 
collar assembly 14 of the present invention, the user inserts jewel light 
pipe assembly 12 into jewel body collar assembly so that longitudinal 
protrusions 74 of jewel light pipe assembly 12 engage blind longitudinal 
slots 60 in jewel body collar assembly 14 and further so that horizontal 
ridge 80 of jewel light pipe assembly 12 engages horizontal section 56 of 
interior grooved section 54 of jewel body collar assembly 14 and vertical 
ridge 82 of jewel light pipe assembly engages vertical section 57 of 
interior grooved section 54 of jewel body collar assembly 14. The user 
then inserts the jewel light pipe assembly 12 and jewel body collar 
assembly 14 so that cylindrical collar 50 of jewel body collar assembly 14 
outwardly concentrically engages support section 38 of knob 10 so as to 
form a bearing surface against the mating bezel (not shown). Additionally, 
proximal portion of light pipe housing assembly 52 which extends inwardly 
radially from a circumference of cylindrical collar 50 is engaged by notch 
40 of cylindrical support portion 38 of knob 10. Horizontal section 56 of 
exterior ridged section 55 of indicator element 53 of jewel body collar 
assembly 14 engages the portion of slot 24 on cylindrical shell 16 while 
vertical section 57 of exterior ridged section 55 of indicator element 53 
of jewel body collar assembly 14 engages the portion of slot 24 on front 
circular face 20. Distal portion of light pipe housing assembly 52 of 
jewel body collar assembly 14 engages notch 25 of cylindrical shell 16 and 
likewise engages a similar reduction of thickness on the interior of front 
circular face 20. These engagements provide for a snap-fit ease of 
assembly. 
The order of assembly of the above elements can be varied. 
Thus the several aforementioned objects and advantages are most effectively 
attained. Although a single preferred embodiment of the invention has 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.