U.S. patent application number 13/372402 was filed with the patent office on 2012-10-18 for color change mechanism.
This patent application is currently assigned to ROBE SHOW LIGHTING S.R.O.. Invention is credited to Pavel JURIK.
Application Number | 20120262923 13/372402 |
Document ID | / |
Family ID | 40843274 |
Filed Date | 2012-10-18 |
United States Patent
Application |
20120262923 |
Kind Code |
A1 |
JURIK; Pavel |
October 18, 2012 |
COLOR CHANGE MECHANISM
Abstract
The present invention provides a drive system for an optical
light modulation system employing multiple light modulation element
pairs. The each pair is driven by a single motor which drives one
axis around which one element of the first pair rotates while the
other element of the first pair free floats and rotates about a
second axis. While the second axis drives the rotation of the first
element of the second pair and the first axis provides a rotation
pivot for the second element of the second pair. Thus the two pairs
share the two axises providing a more compact drive system that can
be used more flexibly in an optical train of an automated
multiparameter lighting system.
Inventors: |
JURIK; Pavel; (Postredni
Becva, CZ) |
Assignee: |
ROBE SHOW LIGHTING S.R.O.
|
Family ID: |
40843274 |
Appl. No.: |
13/372402 |
Filed: |
February 13, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12075465 |
Mar 11, 2008 |
8113691 |
|
|
13372402 |
|
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Current U.S.
Class: |
362/283 |
Current CPC
Class: |
F21W 2131/406 20130101;
F21S 10/02 20130101 |
Class at
Publication: |
362/283 |
International
Class: |
F21V 9/10 20060101
F21V009/10 |
Claims
1. A luminair with light modulation filters in which two pairs of
two modulators are driven by two motors about two axels.
Description
RELATED APPLICATION
[0001] This application is a continuation application for the
purposes of priority of U.S. patent application Ser. No. 12/075,465
filed on Mar. 11, 2008.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention generally relates to the color control
of lighting systems and more specifically to mechanisms used for
color control of entertainment lighting automated multiparameter
luminaires.
BACKGROUND OF THE INVENTION
[0003] Luminaires with automated and remotely controllable
functionality are well known in the entertainment and architectural
lighting markets. Such products are commonly used in theatres,
television studios, concerts, theme parks, night clubs and other
venues. As well as usually providing control over the pan and tilt
functions of the luminaire allowing the operator to control the
direction the luminaire is pointing a typical product will also
often provide control over the color of the emitted light beam.
Typically this color control is done via the movement of color
wheels, flags or other similar device containing colored filters.
Very often these colored filters are gradated from one end to the
other with an increasing density of the color filter or increasing
saturation of the color that is being filtered. Typically, in these
systems the light beam only passes through a portion of the filter.
By moving the gradated filter so that different portions of the
filter are placed in the path of the light beam the color
saturation of the light beam can be varied.
[0004] FIG. 1 shows a filter of this kind with a gradated saw-tooth
color coating 101. Filter 101 is progressively moved from into the
path of the light beam cross section 102 in the light train of the
luminaire anywhere from position a to d. As the movement continues
from position a to d an increasing portion of the light beam cross
section 102 passing through the color modulating portions 103
(shown as the hatched area in FIG. 1) of filter 101 and thus the
resultant light becomes more and more color saturated. When the
filter 101 is in position d the entire cross section 102 passes
through the color modulating portions 103 the filter 101 and the
color saturation is complete for that filter.
[0005] Although a rectangular filter 101 is shown here with linear
motion it is also common for these devices to use circular filters
with a rotary motion.
[0006] A single filter 101 is illustrated here, however in practice
multiple color filters with the same or different color modulating
properties may be used so that the light passes through or bypasses
each filter in turn. Such an arrangement creates a subtractive
color mixing system where the color of the output light is defined
by the combination and position of all the filters in use. The
products manufactured by Robe Show Lighting such as the ColorSpot
1200E are typical of the art.
[0007] In typical color modulation systems a combination of two or
more of these variable saturation mechanisms, one after the other
in the optical train with different colored filters to provide a
variable color mixing system across a color gamut.
[0008] It is very common to use three color filters, one each of
Cyan, Magenta and Yellow each of variable saturation. Combining
these in varying subtractive mixes allows the production of a very
wide gamut of colors.
[0009] Lighting designers and other users of such products often
have a desire to change colors very rapidly. Quickly enough that
the audience does not perceive the change happening and instead
sees it as an instantaneous event. The speed of these changes are
typically limited by the mechanical design and construction of the
mechanism used for the color change.
[0010] FIG. 2 illustrates a typical multiparameter automated
luminaire system 10. These systems typically include a plurality of
multiparameter automated luminaires 12 which typically each contain
on-board a light source (not shown), light modulation devices,
electric motors coupled to mechanical drives systems and control
electronics (not shown). In addition to being connected to mains
power either directly or through a power distribution system (not
shown), each luminaire is connected is series or in parallel to
data link 14 to one or more control desks 16. The luminaire system
is typically controlled by an operator through the control desk
15.
[0011] FIG. 3 illustrates different levels of control 20 of a
parameter of the light emitted from a luminaire. In this example
the levels are illustrated for one parameter: color. The first
level of control 22 is the user who decides what he wants and
inputs information into the control desk through typical through
computer human user interface(s). The control desk hardware and
software then processes the information 26 and sends a control
signal to the luminaire via the data link 14. The control signal is
received and recognized by the luminaire's on-board electronics 28.
The onboard electronics typically includes a motor driver 30 for
the color motor (not shown). The motor driver 30 converts a control
signal into electrical signals which drive the movement of the
color motor. The color motor is part of the color mechanical drive
32. When the motor moves it drives the mechanical drive 32 to move
the mechanical components which cause the light beam emanating from
the luminaire to change color.
[0012] In some systems it may be possible that the motor driver 30
is in the control desk rather than in the luminaire 12 and the
electrical signals which drive the motor are transmitted via an
electrical link directly to the luminaire. It is also possible that
the motor driver is integrated into the main processing within the
luminaire 12. While many communications linkages are possible, most
typically, lighting control desks communicate with the luminaire
through a serial data link; most commonly using an industry
standard RS485 based serial protocol called commonly referred to as
DMX-512.
[0013] Particular problems inhibiting and limiting the speed,
accuracy and repeatability of the movements of the color system of
an automated luminaire are the mechanical stiffness and inertia of
the color mechanism and its drive system. It is typical in such
products to use a single motor or a pair of motors connected to the
driven color change mechanism through either a belt drive or
through a direct geared system. As well as the stated problems in
both cases there is inevitably an amount of backlash or slippage or
shifting which induces hysteresis in the system. Such hysteresis
would manifest itself as an undesirable and visible color shift in
the light output.
[0014] Various prior art systems have offered solutions to these
problems. One solution to reducing the time needed for a color
change is to reduce the length of travel of the mechanism. However
compressing the length of the graded filter (component 101 in FIG.
1) may have the unintended side effect of making the light field
uneven as the color saturation density on one side of the aperture
may be significantly different than on the other.
[0015] There is a need for a color change system which can provide
rapid and accurate movement without backlash and hysteresis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] For a more complete understanding of the present invention
and the advantages thereof, reference is now made to the following
description taken in conjunction with the accompanying drawings in
which like reference numerals indicate like features and
wherein:
[0017] FIG. 1 illustrates a color mixing system of a multiparameter
automated luminaire
[0018] FIG. 2 illustrates a multiparameter automated luminaire
lighting system;
[0019] FIG. 3 illustrates an example of the levels of control which
may be seen in controlling a parameter of an automated
luminaire;
[0020] FIG. 4 illustrates an exemplary embodiment of the mechanical
elements of an embodiment of the present invention;
[0021] FIG. 5 illustrates an partially exploded diagram of the left
half of the embodiment illustrated in FIG. 4;
[0022] FIG. 6 illustrates an elevation for the FIG. 5 illustrated
portion of the embodiment illustrated in FIG. 4;
[0023] FIG. 7 illustrates on example of an optical train and how
the improved color mixing system can be used over a greater range
than prior color mix systems;
[0024] FIG. 8 illustrates on example of an optical train and how
the improved color mix system allows for an over all more compact
fixture/luninaire
[0025] FIG. 9 illustrates an example of a prior art color mix
system as viewed along the optical axis of the system;
[0026] FIG. 10 illustrates an example of the improved color mix
system as viewed along the optical axis of the system;
[0027] FIG. 11 illustrates a color mix pair in full saturation;
and
[0028] FIG. 12 illustrates a color mix pair just entering the light
beam.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Preferred embodiments of the present invention are
illustrated in the FIGUREs, like numerals being used to refer to
like and corresponding parts of the various drawings.
[0030] The present invention generally relates to the color control
of lighting systems and more specifically to mechanisms used for
color control of entertainment lighting automated multiparameter
luminaires.
[0031] The present invention relates to the mechanisms for driving
the color filters in a color mixing system. In one embodiment the
present invention utilizes a single motor for each color driving a
pinion gear. The pinion gear engages with two further pinion gears
to which individual color flags are attached. The axles on which
the second and third pinion gears are mounted are rigidly supported
with a bearing at each end of the axle between two mounting plates.
The mechanical system formed is mechanically stiff and allows rapid
movement of the flags with little hysteresis and vibration in very
little space.
[0032] FIG. 4 illustrate the major mechanical components of the
color changing system of one embodiment of the present invention.
The assembly is based around two rigid mounting plates 202 and 203.
Each of these mounting plates has a light aperture 212. The two
apertures 212 are axially aligned. Attached to the mounting plates
are motors 208, 218, 209, 219 (motor 219 is hidden in FIG. 4 but
shown in FIG. 5 and FIG. 6). The type of motor used is not
important to the invention--the motors may include but are not
limited to stepper motors, DC motors, AC motors or other types of
motors.
[0033] Each motor 208, 218, 209 and 219 drives a pair of light
modulators: one motor 208 drives a modulator pair 204 (the other is
hidden); another motor 218 drives another light modulation pair 207
(the other is hidden); the third motor 209 drives a third set of
modulation pairs 206 and 216; the fourth motor 219 drives a fourth
pair 205 and 215 (modulator 216 is hidden in FIG. 4 but shown in
FIG. 5 and FIG. 6).
[0034] The different light modulator pairs typically have different
modulating effects when introduced to the light beam. In one
embodiment one pair is a pair of cyan filters, a second pair is a
pair of magenta filters, a third pair is a pair of yellow filters
and the fourth pair provides color temperature correction (for
example to make the light beam generated by a metal halide lamp
appear to have the color temperature of an incandescent lamp).
Other modulators are also possible--like a dimmer or other types of
modulators. It is not strictly necessary for there to be a pair of
modulators only one modulator may be employed instead of a pair
however, the unilateral arrangement compromises some of the
benefits such as more even color distribution and lack of vibration
or other movement effects due to unbalanced inertial changes due to
rapid movement of the modulator as further described herein.
[0035] FIG. 5 illustrates a partially exploded view of the left
hand portion of the system driven by motors 209 and 219 for two of
the pairs of modulators 206, 216 and 205, 215 respectively in the
embodiment illustrated in FIG. 4. FIG. 6 illustrates an elevation
view of the partial illustration of FIG. 5. The following applies
as well for the pairs from FIG. 4 not shown in FIG. 5 and FIG. 6.
Each motor 209 and 219 has a geared driving pinion 211 on its
output shaft. The driving pinion 211 engages with a first driven
pinion 223 which, in turn, engages with a second driven pinion 224.
Driven pinions 223 and 224 are the same size. In the system
illustrated driven pinions 223 and 224 are smaller than driving
pinion 211 thus providing a gearing increase. Such a gearing system
may be advantageous for reasons of speed of movement however it is
not a requirement for the present invention. In the embodiment
illustrated both instances of the first driven pinions 223223 are
fixed to axles 228 and second driven pinions 224 are free to rotate
around axles 228. Axles 228 are free to rotate in bearings 225 and
227 mounted in the top and bottom support plates 202 and 203
respectively. The mountings of the bearings in the support plates
is rigid providing secure support for the axle 228 at both ends
which in turn provides a backlash and vibration free support for
the driven pinions 223 and 224.
[0036] A flag support arm 229 is attached to each of the pinions
223 and 224. Each flag support arm supports a color mixing filter
flag 205, 215, 206, 216. The color mixing filter flags are mounted
in pairs of the same color: thus 205 and 215 are one color and 206
and 216 are a second, different, color. One half of each flag pair
(206 for example) is mounted on a driven pinion 223 and the second
half of each flag pair (216 for example) is mounted on the
associated driven pinion 224. In this manner each axle 228 supports
two driven pinions for two different colors. Each axle 228 will
have, on one end, a driven pinion 223 which is fixed to axle 228
and has a flag of a first color and, at the other end of the axle,
a driven pinion 224 which is free to rotate around axle 228 and has
a flag of a second color. This combination and re-use of a single
axle 228 for two flags of different colors halves the total number
of axles 228 and provides an improved compact system. The assembly
is constructed as two, virtually identical sub-assemblies which are
mounted face-to-face sharing axles 228.
[0037] It can be seen from FIG. 5 that rotation of driving pinion
211 in a clockwise direction will cause rotation of driven pinion
223 in a counter clockwise direction which in turn will cause
rotation of driven pinion 224224 in a clockwise direction. Thus
driven pinions 223 and 224224 along with their attached flag
support arms and color mixing filter flags 205 and 215 will be
driven in contrary directions and will open and close across
apertures 212 in the mounting plates 202 and 203.
[0038] The disclosed system has a number of advantages over the
prior art. Firstly the distance traveled by each of the two color
mixing filter flags forming a pair is half that of a single plate
system thus reducing the time for the system to operate.
Additionally the use of two color mixing flags acting in opposition
improves the evenness of the color mixing across the aperture. This
provides for a great deal more flexibility in the positioning of
the system within any given optical light train while its compact
size allows for much greater flexibility in the light train designs
into which it can be incorporated. This flexibility allows for more
compact design of the overall automated luminaire fixture.
[0039] FIG. 7 illustrates how the more compact design and balanced
entry from opposite sides of the light beam allows the present
color mixing system to be used over a greater range along the
optical train of a luminaire 300. The luminaire's light train is
made up of a number of components such as the lamp 302, lamp
reflector 304, aperture 306 and a series of lenses 308, 310. The
present inventions ranges of usefulness 330 are wider since they
can be placed closer to a focal plain then many prior art color
mixing systems which have a more limited range of usefulness
320.
[0040] FIG. 8 illustrates another example of the usefulness of the
present compact design. In this case the overall dimensions of the
luminaire 350 can be more compact because the color mixing system
201 can be placed closer to a focal plain in the optical train of
the luninaire 350.
[0041] FIGS. 9 illustrates a prior art color mixing system with
gradated color wheels 402 and 404. While FIG. 10 illustrates the
more compact design of the present color mixing system. In this
view it is clear to see how much more compact the present system is
in comparison to prior art systems.
[0042] Further because the motion of the two color mixing flags
forming a pair is always equal and opposite there is no net
inertial, vibrational or oscillatory movement induced into the
mounting frames and the rest of the luminaire. Further a
mechanically stiff system with rigidly supported axles and fully
engaged pinion gears ensures accurate movement with little or no
hysteresis or overshoot. Further the sharing of the axles by two
color flags halves the number of axles and produces a compact
system. Further the combination of a fixed pinion and a rotational
pinion on a single shaft reduces the number of bearings in the
system.
[0043] In a further embodiment both pinions 223 and 224 may be free
to rotate on the axle. Both instances of the first driven pinions
223 and second driven pinions 224 are free to rotate around axles
228.
[0044] While the invention has been described with respect to a
limited number of embodiments, those skilled in the art, having
benefit of this invention, will appreciate that other embodiments
may be devised which do not depart from the scope of the invention
as disclosed herein. Accordingly, the scope of the invention should
be limited only by the attached claims.
[0045] The invention has been described in detail, it should be
understood that various changes, substitutions and alterations can
be made hereto without departing from the spirit and scope of the
invention as described by the appended claims.
* * * * *