U.S. patent application number 11/132433 was filed with the patent office on 2005-12-01 for window shade positioning apparatus and method.
Invention is credited to Brzeski, Marek S., Cheever, John Edward, James, Darrell L., Leary, John F., Sievers, Thomas J., Sotto, Elmon D., Yadollahi, Morteza.
Application Number | 20050263254 11/132433 |
Document ID | / |
Family ID | 34936927 |
Filed Date | 2005-12-01 |
United States Patent
Application |
20050263254 |
Kind Code |
A1 |
Sievers, Thomas J. ; et
al. |
December 1, 2005 |
Window shade positioning apparatus and method
Abstract
An aircraft window shade includes protective transparent window
panels, a shade driven by an electric motor, an integral control
panel, and support for remote operation. The shade uses dual
sprocket drive for positive shade positioning, low wear, and low
parts count. The moving shade element remains substantially flat,
curving slightly during some phases of positioning. The apparatus
replaces a conventional interior window panel and a manual shade
with slight change in overall mechanism thickness and weight.
Control electronics in the shade can accept a command from a cabin
attendant's console to override the local setting and move the
shade to a required position, such as fully open for takeoff. The
shade supports use of two or more independent shades, each of which
can be made of dimming (transparent), diffusing (translucent), or
light blocking (opaque) material. The shade is compatible with
electrochromic transmittance control technology.
Inventors: |
Sievers, Thomas J.; (Laguna
Niguel, CA) ; Yadollahi, Morteza; (Irvine, CA)
; Leary, John F.; (Yorba Linda, CA) ; James,
Darrell L.; (Corona, CA) ; Brzeski, Marek S.;
(Long Beach, CA) ; Sotto, Elmon D.; (Montebello,
CA) ; Cheever, John Edward; (Huntington Beach,
CA) |
Correspondence
Address: |
BAKER & HOSTETLER LLP
WASHINGTON SQUARE, SUITE 1100
1050 CONNECTICUT AVE. N.W.
WASHINGTON
DC
20036-5304
US
|
Family ID: |
34936927 |
Appl. No.: |
11/132433 |
Filed: |
May 19, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60574573 |
May 27, 2004 |
|
|
|
Current U.S.
Class: |
160/90 |
Current CPC
Class: |
B64C 1/1484 20130101;
B60J 1/2011 20130101 |
Class at
Publication: |
160/090 |
International
Class: |
E06B 003/32 |
Claims
What is claimed is:
1. A window shade mechanism, comprising: a first diaphragm
incrementally adjustable between an open and a closed position
thereof, the first diaphragm comprising a first outer boundary
extent and a second outer boundary extent, wherein the first outer
boundary extent engages a first guide positioned along a length of
the first outer boundary extent; a first drive sprocket positioned
near the first outer boundary extent of the first diaphragm such
that the first drive sprocket engages the first outer boundary
extent of the first diaphragm; and a first motor coupled to the
first drive socket, wherein the first motor is configured to
actuate the first sprocket such that the first diaphragm is
incrementally adjustable.
2. The window shade mechanism as in claim 1, wherein the second
outer boundary extent of the first diaphragm comprises a second
guide positioned along a length of the second outer boundary extent
of the first diaphragm.
3. The window shade mechanism as in claim 2, further comprising: a
second drive sprocket positioned near the second outer boundary
extent of the first diaphragm such that the second drive sprocket
is configured to engage the second outer boundary extent of the
first diaphragm; and a coupling between the first motor and the
second drive sprocket, wherein the first motor is configured to
actuate the second sprocket such that the first diaphragm is
incrementally adjustable.
4. The window shade as in claim 3, wherein the first outer boundary
extent of the first diaphragm further comprises first
receptacles.
5. The window shade as in claim 4, wherein the first drive sprocket
further comprises a first plurality of teeth that are configured to
engage the first receptacles.
6. The window shade as in claim 5, wherein the second outer
boundary of the first diaphragm extent further comprises second
receptacles, and wherein the second drive sprocket further
comprises a second plurality of teeth that are configured to engage
the second receptacles.
7. The window shade as in claim 6, further comprising: a first
drive shaft, whereto the first and second drive sprockets are
affixed at a lockable angle, whereby engagement between the first
plurality of teeth and the first receptacles and engagement between
the second plurality of teeth and the second receptacles are
substantially synchronizable; a first drive shaft bearing pair
configured to locate and permit rotation of the first drive shaft,
wherein the first drive shaft and the first and second drive
sprockets affixed thereto establish engagement of the first and
second drive sprockets with the first and second receptacles,
respectively; a first motor drive gear affixed to a first motor
output shaft; and a first drive shaft driven gear on the first
drive shaft, meshed with the first motor drive gear, whereby
rotation of the first motor output shaft is coupled to the first
drive shaft.
8. The window shade as in claim 7, further comprising: a first
motor encoder, whereby rotation of the first motor is detectable; a
first diaphragm closed end of travel detector, configured such that
a signal therefrom indicates that the first diaphragm is in a fully
closed position; and a first diaphragm open end of travel detector,
configured such that a signal therefrom indicates that the first
diaphragm is in a fully opened position.
9. The window shade as in claim 8, further comprising: a second
diaphragm incrementally adjustable between an open and a closed
position, the second diaphragm comprising a first and a second
outer boundary extent, respectively, wherein the first and second
outer boundary extents engage a third and a fourth guide,
respectively, positioned along a length of the first and second
outer boundary extents, respectively; a third drive sprocket
positioned near the first outer boundary extent of the second
diaphragm such that the third drive sprocket engages the first
outer boundary extent of the second diaphragm; a fourth drive
sprocket positioned near the second outer boundary extent of the
second diaphragm such that the fourth drive sprocket engages the
second outer boundary extent of the second diaphragm; and a second
motor coupled to the third and fourth drive sprockets, wherein the
second motor is configured to actuate the third and fourth
sprockets such that the second diaphragm is incrementally
adjustable.
10. The window shade as in claim 9, wherein the first and second
outer boundary extents of the second diaphragm further comprise
third and fourth receptacles, respectively, and wherein the third
and fourth drive sprockets further comprise a third and a fourth
plurality of teeth configured to engage the third and fourth
receptacles, respectively.
11. The window shade as in claim 10, further comprising: a second
drive shaft whereto the third and fourth drive sprockets are
affixed at a lockable angle, whereby engagement between the third
plurality of teeth and the third receptacles, and between the
second plurality of teeth and the second receptacles of the second
diaphragm, respectively, are substantially synchronizable; a second
motor drive gear affixed to a second motor output shaft; a second
drive shaft driven gear on the second drive shaft, meshed with the
second motor drive gear, whereby rotation of the second motor
output shaft is coupled to the second drive shaft; a second motor
encoder, whereby rotation of the second motor is detectable; a
second diaphragm closed end of travel detector, configured such
that a signal therefrom indicates that the second diaphragm is in a
fully closed position; and a second diaphragm open end of travel
detector, configured such that a signal therefrom indicates that
the second diaphragm is in a fully opened position.
12. The window shade as in claim 11, further comprising at least
one additional component, wherein the component is selected from
the list consisting of: a first window panel, configured to provide
a mechanical barrier between the diaphragms and locations inboard
of the window shade, further configured to admit substantially all
light not blocked by the diaphragms from sources outboard of the
window shade to locations inboard of the window shade, further
configured to align substantially with a window element of a
structure whereto the window shade is attached; a first window
panel attachment fitting, configured to retain the first window
panel as an integral element of the window shade apparatus; a
second window panel, configured to provide a mechanical barrier
between the movable diaphragms and any materials outboard of the
window shade, further configured to admit substantially all light
not blocked by the diaphragms from sources outboard of the window
shade to locations inboard of the window shade, further configured
to align substantially with a window element of a structure whereto
the window shade is attached; a second window panel attachment
fitting, configured to retain the second window panel as an
integral element of the window shade apparatus; a diaphragm cover,
wherein the diaphragm cover substantially encloses a portion of at
least one diaphragm, wherein the diaphragm portion enclosed within
the cover is retracted from a diaphragm position between the first
and second window panels; a first motor mount, whereby the first
motor is attached to the window shade mechanism; a second motor
mount, whereby the second motor is attached to the window shade
mechanism; a first guide shoe, whereby a distance between the first
outer boundary extent of the first diaphragm and the first sprocket
at a point of tangency therebetween is maintained; and a mounting
provision, whereby the window shade is attachable to a structure
external thereto.
13. The window shade as in claim 12, further comprising a control
system, wherein the control system further comprises: a power
inlet; an input power conditioner; a local control panel; a local
control panel backlight; a discrete command signal input port; a
remote message transceiver; a command processor; an information
storage element; and a first motor drive circuit.
14. The window shade as in claim 13, further comprising a control
system, wherein the control system further comprises: a local
command interpreter; a discrete command interpreter; a remote
signal input message parser; a device address recording provision;
a device address comparator; a parsed remote command interpreter; a
remote signal reply message formatter; an authentication code
generator; a first motor speed comparator function; a first motor
speed compensator function; a soft start function; a first shade
position calculation function; a first shade position storage
function; a first shade position recall function; a first shade
position comparator function; an abuse detection function; an abuse
override function; a local control disable function; an
uncompensatable speed error detection function; an uncompensatable
position error detection function; an end-to-end count error
detection function; a cumulative run time totalization function; an
error recording function; and a status report generator
function.
15. The window shade as in claim 14, further comprising a manual
override, wherein the manual override further comprises: a spool
wherein the spool receives drive from an externally applied
rotational source; a lifter, configured to remain at rest, during
normal shade operation, outside a range of view through the windows
at the closed end of travel of the diaphragms, further configured
to translate toward the open end of travel of the diaphragms upon
application of tension, further configured to couple tension to the
diaphragms, whereby the diaphragms are translated to the open end
of travel thereof; a tension cable, attached to the spool,
configured to apply tension to the lifter in a direction tending to
translate the lifter toward the open end of travel of the
diaphragms, wherein the tension cable is so attached to the lifter
as to apply a substantially balanced lifting force thereto; and a
pulley set, configured to direct balanced lifting force to the
lifter by distribution and direction of tension applied the tension
cable by rotation of the spool.
16. The window shade as in claim 15, wherein the first diaphragm
further comprises: a property of opacity sufficient to block
substantially all visible light impinging on the diaphragm; a shape
conforming substantially to a rectangular prism, wherein dimensions
along a first and a second respectively-orthogonal axis of the
shape establish an area comparable to a light admitting area of a
window wherebefore the window shade is installed, wherein a
dimension of the shape along a third orthogonal axis is no greater
in size than one tenth of the smaller of the first and second
dimensions, wherein the first and second boundary extents of the
diaphragm extend along one of the first and second orthogonal axes
of the shape, wherein all edges and corners of the shape have any
respective radii of curvature, whereby an extent of planar surface
area parallel to the third axis is as little as zero; and a
property of flexibility sufficient to sustain repeated deflection
from a first substantially planar surface of motion along a curved
guide to a second substantially planar surface of motion.
17. The window shade as in claim 16, wherein the second diaphragm
further comprises: A property of light management having at least
one attribute selected from the list consisting of reducing light
intensity while allowing images to be seen substantially clearly
therethrough, and diffusing light while reducing light intensity,
whereby substantially no images are readily discernable
therethrough; a shape conforming substantially to a rectangular
prism, wherein dimensions along a first and a second
respectively-orthogonal axis of the shape establish an area
comparable to a light admitting area of a window wherebefore the
window shade is installed, wherein a dimension of the shape along a
third orthogonal axis is no greater in size than one tenth of the
smaller of the first and second dimensions, wherein the first and
second boundary extents of the diaphragm extend along one of the
first and second orthogonal axes of the shape, wherein all edges
and corners of the shape have any respective radii of curvature,
whereby an extent of planar surface area parallel to the third axis
is as little as zero; and a property of flexibility sufficient to
sustain repeated deflection from a first substantially planar
surface of motion along a curved guide to a second substantially
planar surface of motion.
18. A window shade mechanism, comprising: a movable first window
shade diaphragm, wherein a first tractionable boundary region of
the diaphragm and a second tractionable boundary region of the
diaphragm are configured in parallel and at opposed extents of the
diaphragm; a first diaphragm drive sprocket, wherein the first
sprocket engages the first tractionable boundary region of the
diaphragm; a second diaphragm drive sprocket, wherein the second
sprocket engages the second tractionable boundary region of the
diaphragm; and a first motor coupled to the first and second
sprockets.
19. The window shade mechanism of claim 18, further comprising: a
first substantially optically transparent panel, positioned
substantially parallel to and substantially conterminous with the
first diaphragm, having a generally uniform first view surface and
having a second view surface generally parallel to the first view
surface; a second substantially optically transparent panel,
configured substantially parallel to the first transparent panel,
and positioned oppositely from the first transparent panel with
respect to the first diaphragm, whereby an enclosed volume is
defined wherewithin the first diaphragm is positioned when
closed;
20. The window shade mechanism of claim 18, wherein the first
tractionable boundary region of the first diaphragm further
comprises a first row of drive tooth receptacles, wherein the
second tractionable boundary region of the first diaphragm further
comprises a second row of drive tooth receptacles substantially
parallel to the first row thereof, wherein a traction portion of
the first sprocket and a traction portion of the second drive
sprocket are substantially identical, and wherein each respective
traction portion further comprises: a respective drive sprocket
perimeter surface region; a plurality of sprocket drive teeth
projecting from the respective drive sprocket perimeter surface
regions, wherein the drive teeth are of such shape and spacing as
to engage the respective diaphragm drive tooth receptacles; and
respective first and second sprocket guide shoes, configured to
maintain respective first and second spacings, whereby the
respective sprocket teeth engage the respective tooth receptacles
proximal to a closest point of approach between the respective
drive sprockets and the respective guide shoes.
21. The window shade mechanism of claim 20, further comprising: a
first panel mounting frame wherewithin the first transparent panel
is fitted; a second panel mounting frame wherewithin the second
transparent panel is fitted; a first side rail connecting the first
and second panel mounting frames on a first side; a second side
rail connecting the first and second panel mounting frames on a
second side; a cross rail connecting the first and second panel
mounting frames distal to the first shade first and second guide
shoes, wherein the cross rail further comprises a connection
between the first and second side rails; and a diaphragm cover
enclosing a sheltered volume substantially external to the volume
between and including the first and second transparent panels,
wherein the sheltered volume is configured to house any portion of
the first shade diaphragm not interposed between the first and
second transparent panels and not otherwise housed, wherein the
cover further comprises a continuation of the sheltered volume
configured to house at least in part at least one of the first
shade drive motor, the first shade sprockets, the first shade guide
shoes, and a first shade drive shaft providing a torque coupling
between the first shade sprockets.
22. The window shade mechanism of claim 21, further comprising: a
first guide slot associated with the first side rail, wherein the
first guide slot is configured to permit the first diaphragm to
translate substantially freely in order to follow the median path
of the first shade diaphragm; a second guide slot associated with
the second side rail, wherein the second guide slot is configured
to permit the first diaphragm to translate substantially freely in
order to follow the median path of the first shade diaphragm; a
first boundary surface light trap associated with the cross rail,
wherein the light trap is configured to engage a closure boundary
surface of the first diaphragm at a closure extent of travel; and a
first drive end gap occupying a space between the first transparent
panel and the second transparent panel, comparable in extent to the
first boundary surface light trap, proximal to the first shade
sprockets, and configured to allow motion of the first diaphragm
between the volume generally enclosed between the first and second
transparent panels and the volume generally enclosed within the
cover.
23. The window shade mechanism of claim 22, wherein the respective
first and second side rail first guide slots further comprise:
respective pairs of facing surfaces configured with longitudinal
extents roughly equal to those of the respective side rails,
wherein the respective pairs of facing surfaces are configured with
lateral extents sufficient at least to enclose the shade diaphragm
drive tooth receptacles, wherein the respective pairs of facing
surfaces are each configured with slot profiles between facing
surfaces of the slots to accommodate substantially free translation
of thickness profiles of the diaphragm and the diaphragm drive
tooth receptacles, and wherein the pairs of facing surfaces are
joined respectively by a first side rail first slot union surface
and a second side rail first slot union surface, wherein each union
surface is distal to the centroid of the first shade diaphragm; and
respective first and second light baffles, wherein the respective
first and second light baffles substantially block passage of
visible light around respective proximal boundary surfaces of a
diaphragm fitted within the respective first and second side rail
first and second guide slots, and wherein the respective first and
second light baffles further substantially block passage of visible
light through the associated diaphragm drive tooth receptacles.
24. The window shade mechanism of claim 23, wherein the first shade
closure slot further comprises: a pair of closure facing surfaces
joined by a closure union surface proximal to a closure extent of
travel of the first shade diaphragm, wherein the closure facing
surfaces are configured with a longitudinal extent roughly equal to
the distance between the first and second side rail first guide
slot union surfaces, wherein the closure facing surfaces are
configured with a depth sufficient to enclose a shade diaphragm
closure boundary surface distal to the drive sprockets, and wherein
the facing surfaces are configured with a slot profile between
facing surfaces to accommodate substantially free insertion and
withdrawal of the closure boundary surface of the first shade
diaphragm; and a third light baffle, wherein the third light baffle
substantially blocks passage of visible light around a boundary
surface distal to the drive sprockets of a shade diaphragm fully
inserted into the first shade closure slot.
25. The window shade mechanism of claim 24, wherein the shade drive
end gap further comprises: a pair of drive end gap facing surfaces,
wherein the drive end gap facing surfaces are configured with a
longitudinal extent roughly equal to the distance between the first
and second side rail first guide slot union surfaces, wherein the
drive end gap facing surfaces are configured with a slot profile
between the drive end gap facing surfaces to accommodate
substantially free insertion and withdrawal of the first shade
diaphragm; and a fourth light baffle, wherein the fourth light
baffle substantially blocks passage of visible light around a
boundary surface of a shade diaphragm fully inserted into the first
shade closure slot, and wherein the boundary surface is proximal to
the drive end of the housing.
26. The window shade mechanism of claim 18, further comprising: a
first drive shaft connecting the first and second drive sprockets,
whereby the first and second sprockets rotate at a substantially
proportional rim rate; a first drive shaft bearing pair, configured
to locate and permit rotation of the first drive shaft, whereby the
first drive shaft and the first and second drive sprockets affixed
thereto establish engagement of the first and second drive
sprockets with the first and second receptacles, respectively; a
first motor drive gear affixed to a first motor output shaft; and a
first drive shaft driven gear on the first drive shaft, meshed with
the first motor drive gear, whereby rotation of the first motor
output shaft is coupled to the first drive shaft.
27. The window shade mechanism of claim 20, further comprising: a
movable second window shade diaphragm, comprising a specified
combination of light transmittance and transparency, comprising
substantially parallel first and second shade surfaces, and further
comprising a substantially parallel first side surface and second
side surface connecting the first and second shade surfaces,
wherein the second diaphragm is configured to translate
bidirectionally along a median path parallel to a median line
substantially equidistant between a first edge joining the first
shade surface and the first side surface and a second edge joining
the first shade surface and the second side surface of the second
diaphragm, wherein the second diaphragm further comprises
respective first and second tractionable boundary regions proximal
to the respective first and second edges; a third diaphragm drive
sprocket coupled to the second diaphragm, proximal to the first
tractionable boundary region thereof; a fourth diaphragm drive
sprocket coupled to the second diaphragm proximal to the second
tractionable boundary region thereof; a second diaphragm drive
shaft connecting the third and fourth drive sprockets, whereby the
third and fourth sprockets rotate substantially in synchronism;
respective third and fourth guide shoes configured to maintain
respective third and fourth spacings between the respective third
and fourth drive sprockets and the second diaphragm; and a second
motor, coupled to the second diaphragm drive shaft.
28. The window shade mechanism of claim 27, wherein the respective
second shade diaphragm tractionable boundary regions further
comprise respective first and second parallel rows of drive tooth
receptacles; wherein respective second diaphragm coupling portions
of the third and fourth drive sprockets are substantially
identical, and wherein each second diaphragm coupling portion
further comprises: a drive sprocket perimeter surface region; and a
plurality of radially oriented drive sprocket drive teeth
projecting from the second shade drive sprocket perimeter surface
region, wherein the drive teeth are of such shape and spacing as to
engage the second shade diaphragm drive tooth receptacles.
29. The window shade mechanism of claim 21, wherein the first
transparent panel and the first panel mounting frame comprise a
single unit, and wherein the second transparent panel and the
second panel mounting frame comprise a single unit.
30. The low profile window shade mechanism of claim 21, wherein the
first shade first guide shoe and the first side rail comprise a
single unit, and wherein the second shade first guide shoe and the
second side rail comprise a single unit.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to provisional U.S. patent
application entitled, "WINDOW SHADE MECHANISM," filed May 27, 2004,
having a Ser. No. 60/574,573, the disclosure of which is hereby
incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to electronically
controlled mechanical positioning devices. More particularly, the
present invention relates to remotely controllable window
shades.
BACKGROUND OF THE INVENTION
[0003] Window shade mechanisms for commercial aircraft cabin
windows serve purposes such as darkening the cabin of an aircraft
independent of outside light levels and reducing sunlight glare.
Applying substantially complete darkening to an aircraft cabin may
be desirable for adapting to a destination's time zone, for
example, or allowing a movie to be shown from a central screening
location without intrusive light.
[0004] Glare reduction is often applied by individual passengers by
lowering a shade part way, although such solutions may prove
unsatisfactory in some cases with existing window shade styles.
[0005] A manually operated window shade, the most familiar form of
this device, is presently used in many aircraft. While such shades
are arguably inexpensive and generally reliable, a window fitted
with a manual shade may be difficult to restore if the shade fails,
while the shade itself can provide only a limited range of
functions--basically, interposing a light-blocking membrane from
the top of a window opening as far down as the user chooses.
[0006] Air carrier regulations can require shades to be fully open
during takeoff and landing. Applying uniform window shade
positioning throughout an aircraft generally necessitates
cooperation by passengers, while a flight or ground crew member
must move from row to row, checking or moving every shade
individually, which can be labor-intensive and time consuming.
[0007] Typical existing motorized aircraft window shades use fan
fold shade media--i.e., media creased into strips and formed into a
stack--to extend and withdraw the shade from the viewing area.
These designs depend on a combination of durability, self-hinge
flexibility, and opacity in the shade media, as well as durability
in the remainder of the involved parts, to achieve reliability
goals, and have in many cases proven susceptible to wear. In
addition, many such designs, constrained by a need to accumulate
the fan folded shade media in a generally horizontal stack, are
undesirably thick, intruding into the aircraft cabin to a greater
extent than is required for other aircraft structural elements,
such as fuselage insulation. Such designs additionally can have
perimeter light leaks, since the individual panels of the fan
folded shade media assume a range of angles, so that a thorough and
cost effective light trap along the boundaries of the shade may be
extensive in width or infeasible.
[0008] Other design approaches can show drawbacks as well. Typical
shade designs in which the shade media is gathered on a spool can
have limitations comparable to those of fanfold shades. Shade media
driven between pinch rollers may rely on roller traction, which is
affected by aging, temperature, contamination, and other factors,
and can develop misalignment.
[0009] Accordingly, it is desirable to provide a method and
apparatus that allow the darkening and glare reduction functions of
a window shade to be electronically controllable by an individual
passenger. It is further desirable that these functions be provided
by a shade assembly that has low thickness and weight, that is
housed within a self-contained cassette, that exhibits durability
and freedom from environmental degradation, and that can be
positioned from a remote location.
SUMMARY OF THE INVENTION
[0010] The foregoing needs are met, to a great extent, by the
present invention, wherein in one aspect an apparatus is provided
that in some embodiments encloses a movable, light-blocking window
shade element, an associated motorized positioner, and a control
mechanism inside a thin, low weight, self-contained cassette, so
that application of electrical power, with or without additional
control signals, allows the shade to be moved to a position
selected by a local user. The invention further allows more than
one shade element to be included in the cassette, and further
allows at least one shade position to be set by at least one remote
operator.
[0011] In accordance with one embodiment of the present invention,
a window shade mechanism is presented. The window shade mechanism
includes a first diaphragm incrementally adjustable between an open
and a closed position thereof, the first diaphragm comprising a
first outer boundary extent and a second outer boundary extent
thereof, wherein the first outer boundary extent thereof engages a
first guide positioned along a length of the first outer boundary
extent thereof, a first drive sprocket positioned near the first
outer boundary extent of the first diaphragm such that the first
drive sprocket engages the first outer boundary extent of the first
diaphragm, and a first motor coupled to the first drive socket,
wherein the first motor is configured to actuate the first sprocket
such that the first diaphragm is incrementally adjustable.
[0012] In accordance with another embodiment of the present
invention, a window shade mechanism is presented. The window shade
mechanism includes a movable first window shade diaphragm further
comprising a specified combination of light transmittance and
transparency, wherein a first tractionable boundary region of the
diaphragm and a second tractionable boundary region of the
diaphragm are configured in parallel and at opposed extents of the
diaphragm, a first diaphragm drive sprocket, wherein the first
sprocket engages the first tractionable boundary region of the
diaphragm, a second diaphragm drive sprocket, wherein the second
sprocket engages the second tractionable boundary region of the
diaphragm, and a first motor coupled to the first and second
sprockets.
[0013] There have thus been outlined, rather broadly, certain
embodiments of the invention in order that the detailed description
thereof herein may be better understood, and in order that the
present contribution to the art may be better appreciated. There
are, of course, additional embodiments of the invention which will
be described below and which will form the subject matter of the
claims appended hereto.
[0014] In this respect, before explaining at least one embodiment
of the invention in detail, it is to be understood that the
invention is not limited in its application to the details of
construction and to the arrangements of the components set forth in
the following description or illustrated in the drawings. The
invention is capable of embodiments in addition to those described
and of being practiced and carried out in various ways. Also, it is
to be understood that the phraseology and terminology employed
herein, as well as the abstract, are for the purpose of description
and should not be regarded as limiting.
[0015] As such, those skilled in the art will appreciate that the
conception upon which this disclosure is based may readily be used
as a basis for the designing of other structures, methods, and
systems for carrying out the several purposes of the present
invention. It is important, therefore, that the claims be regarded
as including such equivalent constructions insofar as they do not
depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a perspective view illustrating a window shade
assembly according to a preferred embodiment of the invention.
[0017] FIG. 2 is a perspective view of the cassette of FIG. 1 with
the diaphragm cover removed.
[0018] FIG. 3 is a perspective view of a drive motor, a drive
assembly, and a portion of a guide assembly.
[0019] FIG. 4 is a face view of a cassette showing more drive
details.
[0020] FIG. 5 is a section view per FIG. 4.
[0021] FIG. 6 is an exploded view of a cassette.
[0022] FIG. 7 is a block diagram illustrating the electronic
hardware elements of a dual shade position controller.
[0023] FIG. 8 is a view of a normal installation of a cassette
having a manual override mechanism.
[0024] FIG. 9 is a view of a cassette prepared for actuation of the
manual override mechanism.
[0025] FIG. 10 is an exploded view showing the manual override
mechanism of a cassette.
DETAILED DESCRIPTION
[0026] The invention will now be described with reference to the
drawing figures, in which like reference numerals refer to like
parts throughout. An embodiment in accordance with the present
invention provides a window shade cassette that accommodates to an
aircraft fuselage contour, has low weight and thin profile, can be
operated electronically by a passenger using a control device, and
can further be operated remotely. In some embodiments, the shade
can combine light reducing and light blocking functions.
[0027] FIG. 1 is a perspective view showing a self-contained window
shade cassette 10 with a diaphragm cover 12 attached to a housing
assembly 14. Mounting flanges 16 are provided for ease of
attachment to an aerostructure.
[0028] Set into the inboard (i.e., passenger-side) and outboard
(i.e., exterior-side) panels of the housing assembly 14 are panels
made from a suitable window pane material, the properties of which
in some embodiments combine visual clarity, thinness, and low
weight with resistance to scratching, shattering, and chemical
attack. Visual clarity of a quality referred to as optical
transparency is generally understood to imply that scant evidence
of the interposed panels will be detectable either by direct
inspection or in (non-flash) photographs taken through the panels.
The inboard transparent panel 18 is intended for direct exposure to
the aircraft interior, and is thus likely to be subject to grooming
products, skin oils, cleaning agents, and other chemical exposure,
as well as to contact with dust particles, tobacco smoke, solid
objects, and other abrasives.
[0029] Because scratches and other damage to the inboard
transparent panels 18 are likely to occur despite good choices of
materials, it is desirable, for some embodiments, that the inboard
panels 18, at least, be readily replaceable. Ready replaceability
may be enhanced by providing an interlocking inboard housing plate
22 that can be attached to the cassette 10, for example using
fasteners such as screws, so that the inboard housing plate 22
clamps the inboard transparent panel 18 in place when attached. In
other embodiments, it may be preferable that a similar
configuration be assembled using integral interlocking elements
between the inboard housing plate 22 and left- and right-side side
rails 36 and 38, shown in FIGS. 2 and 6, thereby eliminating one or
more separate metal fastenings. In still other embodiments, it may
be preferable to form the inboard housing plate 22 and the inboard
transparent panel 18 in a single replaceable unit, wherein the
single unit is all transparent, is co-molded from multiple
materials, or is given an opaque coating in part, thereby
eliminating the housing plate 22 as a separate component. In yet
other embodiments, it may be preferable to treat part or all of the
cassette 10 as disposable, rather than supporting the transparent
panel 18 as a replaceable component.
[0030] The housing portion 14 of the cassette in the embodiment
shown is made up of several components (see FIG. 6 for an exploded
view) to which the inboard 18 and outboard 20 transparent panels
are attached. The diaphragm cover 12 functions as a protective
enclosure over the motor drive assembly or assemblies (see FIGS. 2
and 3 for more detail) and over the travel path and storage
location of one or more shade diaphragms when the diaphragms are
retracted.
[0031] FIG. 2 is a perspective view showing the cassette 10 of FIG.
1 with the diaphragm cover 12 removed. The section line 3
identifies the view of FIG. 3, in which a representative motor and
drive assembly within a dual-shade configuration is shown. In FIG.
2, the outboard and inboard shade drive motors 24 and 26,
respectively, are coupled to outboard and inboard rectangular shade
diaphragms 28 and 30, respectively. The diaphragms 28 and 30 are
positioned by pairs of inboard guide slots 32 and outboard guide
slots 34, respectively, with one of each of the slots 32 and 34
located in (viewed from inboard) left side and right side dual-slot
side rails 36 and 38, respectively. The right side rail 38 is
attached to the outboard drive motor 24 by a right motor mount 40,
while the inboard drive motor 26 is attached to the left side rail
36 by a left motor mount 42.
[0032] FIG. 3 shows the left dual-slot side rail 36 viewed from
roughly the angle of FIG. 2, with the cover (12 in FIG. 1),
diaphragms (28 and 30 in FIG. 2), and left motor mount (42 in FIG.
2) omitted for clarity. A pinion 44 attached to the inboard drive
motor 26 meshes with a driven gear 46 attached to an inboard
diaphragm drive shaft 48. The curvature of the outboard and inboard
guide slots 32 and 34, respectively, above the motor area directs
the diaphragms 28 and 30, shown in FIG. 2, along generally
parallel, deflected, substantially straight paths, to which the
cover 12, shown in FIG. 1, generally conforms. The angle offset
afforded by the curvature permits the cassette 10 to conform in
part to the profile of some aircraft fuselages. The extent to which
guide slots 32 and 34 are curved may be determined by the
requirements of specific applications, and may be limited by drag
and wear considerations for specific combinations of guide and
diaphragm materials. The cover 12 may provide further deflection in
some embodiments.
[0033] FIG. 4 is an inboard-side face view of the cassette 10 with
the diaphragm cover (12, shown in FIG. 1) and diaphragms (28 and
30, shown in FIG. 2) omitted. In this view, the inboard drive shaft
48 and the outboard drive shaft 50 with their respective driven
gears 46 and 52 may be seen. In an arrangement equivalent to that
shown in FIG. 3, the outboard drive motor 24 is connected to an
outboard pinion 54 that drives the outboard driven gear 52, which
is in turn coupled to the outboard shaft 50. Bearing cups 56
support and locate the two shafts 48 and 50 at each end thereof.
Also visible in this view are inboard sprockets 58, which are
coupled to inboard shaft 48, and outboard sprockets 60, which are
coupled to outboard shaft 50. Diaphragm position sensors 104, 106,
108, and 110, and control panel 82 elements, shown in this view,
will be discussed in functional terms below under FIG. 7, the
functional block diagram.
[0034] FIG. 5 is a section according to the cut plane 5-5 in FIG.
4, looking to the right through the right dual-slot side rail 38 in
the center plane of the outboard diaphragm sprocket teeth 70, with
the diaphragm cover 12 and the outboard diaphragm 28 shown to
clarify the relationship between the drive sprockets and the
diaphragms. The interface between the outboard diaphragm 28 and the
outboard drive sprockets 60 attached to the outboard drive shaft 50
is the rows of outboard drive holes 62, of which rows both are
shown in FIG. 2, in the outboard diaphragm 28. The region of the
surface of the outboard diaphragm guide slot 32 proximate to the
outboard drive sprocket 60 and forming with the sprocket 60 a
passage for the diaphragm 28 functions as a guide shoe 64 to
regulate the position of the outboard diaphragm 28 with respect to
the outboard drive sprocket teeth 70, and thus to control mesh
between the sprocket teeth 70 and the outboard diaphragm holes 62.
An equivalent arrangement couples the inboard diaphragm 30 to the
inboard drive sprockets 58, shown in FIG. 3, and attached to the
inboard shaft 48. Rows of inboard drive holes 74 in the inboard
diaphragm 30, shown in FIG. 2, are captured between the inboard
sprockets 58, shown in FIG. 4. A proximal portion of each inboard
guide slot 34 similarly forms a guide shoe (not visible in FIG. 5)
regulating mesh between the teeth of inboard sprocket 58 and the
inboard diaphragm holes 74, shown in FIG. 2.
[0035] FIG. 5 further clarifies the relationship between the
outboard shade diaphragm 28 and the drive mechanism. In the
embodiment shown, the outboard sprocket 60 has a substantially
cylindrical outer surface 68 that makes rolling contact with the
outboard diaphragm 28. Sprocket teeth 70 that protrude from the
sprocket outer surface 68 preferably have a profile that allows
entry into and release from outboard diaphragm drive holes 62
without significant sliding contact. The outboard guide slot guide
shoe 64 area is positioned with respect to the sprocket surface 68
to maintain low friction while assuring that the diaphragm 28
accepts and releases the sprocket teeth 70 without appreciable
binding.
[0036] A diaphragm in a shade according to the present invention
may be substantially completely light blocking, i.e., opaque, or
may be either translucent (largely diffusing) or semitransparent
(dimming but allowing outside objects to be seen clearly). A
two-diaphragm shade may incorporate a combination of these types. A
three- or four-diaphragm shade is likewise feasible; some
combination of increased miniaturization, changes in materials
selection, increased overall cassette thickness, and widening of
the guide slot region between the mounting flanges 16 and the
transparent panels may be required to accommodate a succession of
increasingly widely spaced drive sprockets and their diaphragms. In
a typical application with more than two diaphragms, additional
motor and drive assemblies are narrower, are configured below the
two shown in FIG. 2, and operate narrower diaphragms mounted
further inboard (or the converse), while the added electronic
functions include sensor, control, and driver circuits for the
additional motors and diaphragms.
[0037] FIG. 6 is an exploded diagram of the cassette 10, showing
the structural elements of the components described above. In this
view, the individual elements making up a complete cassette 10
according to a representative embodiment are shown using the same
reference numerals as above. In the embodiment shown, the dual-slot
side rails 36 and 38 are represented as single units that
incorporate, in addition to respective motor mount attachment
surfaces 116, and sprocket clearance apertures 66, attachment frame
elements 118 connecting the inboard and outboard housing plates 22
and 78, respectively, and diaphragm guide/light block elements 32
and 34, guide shoe regions 64 and 76, and drive shaft bearing cups
56 (partially obscured in this view, but each visible in at least
one of FIGS. 3, 4, and 5). Each of these elements may in some
embodiments be integral with the rails, may each be a separate
component, or may be molded separately and incorporated by multiple
injection molding into a single component. The cross rail 80, with
its bottom light trap 72, discussed below, receives a control panel
82 and provides a connector 96 interface.
[0038] Assurance of substantially complete light blocking for a
light-blocking diaphragm can be enhanced by providing a continuous
light baffle on each boundary of the diaphragm. This can be
achieved by using structural elements and a diaphragm 28 that are
substantially completely opaque for all visible wavelengths, and by
providing guide slots 32 and a bottom boundary surface light trap
72 that largely obstruct light reflections.
[0039] A gap between the inboard and outboard mounting frames 22
and 78, respectively, shown in FIG. 6, allows passage of the
diaphragm 28 from a storage position within in the housing 12 into
a light blocking position between the inboard and outboard
transparent panels 18 and 20, respectively. In some embodiments,
provision of a substantially opaque and nonreflective housing 12
permits the gap between mounting frames 22 and 78 to occupy the
full extent of the space therebetween, without permitting
appreciable passage of light past the closed diaphragm 28. In other
embodiments, provision of an additional component between the guide
rails 36 and 38, proximal to the housing 12, and having a
light-blocking slot through which each diaphragm passes, may be
incorporated to increase light blockage.
[0040] Thinness and uniformity in the diaphragm 28 and closeness of
diaphragm fit in the guide slots 32 can further improve blocking.
For example, a close fit between slots 32, bottom trap 72, and
diaphragm 28 in the closed position can increase the number of
reflections necessary for a light ray to travel around the
diaphragm 28, and can thus increase attenuation of unwanted light.
Material color and surface finish in some embodiments can
contribute to a reduction in light path reflectivity. Black color
and a specified degree of surface roughness, for example, may be
preferred. Multiple grooves of specified dimensions in the guide
slot 32 and bottom trap 72, with the grooves typically parallel to
the proximal diaphragm 28 boundary surface, may likewise attenuate
unwanted light in some embodiments.
[0041] Returning to FIG. 4, a local user interface may be seen,
including the control panel 82 integrated with the cassette 10. A
control panel 82 having one or more momentary-contact button-style
membrane switches in a keypad 84 can command motion for the
diaphragms 28 and 30 according to a preferred electronic
embodiment. For example, in the two-button arrangement shown, an
"up" button 86 and a "down" button 88 as shown in FIG. 4 can be
used to command the diaphragms to move sequentially--that is, a
first diaphragm normally moves to an end of travel and stops before
the same button can command the second diaphragm to move in the
same direction, where the identity of the first diaphragm is
defined by the implementer. For another example, an embodiment can
allow a user to command go-to-end capability for the currently
active diaphragm, such as by configuring the controller (discussed
in FIG. 7, below) to detect a rapid double press of a button.
[0042] Each button can feature tactile feel (a slight "click"
sensation when applied pressure is in a desired force range). The
keypad 84 can use a monolithic, durable, flexible cover film. A
cover film, if used, can provide a translucent or transparent zone,
either immediately over each button or over an area that includes
both the buttons 86 and 88 and some portion of their surroundings,
so that a backlight 90 can be provided to identify and allow
distinguishing the buttons 86 and 88 in low-light environments. The
buttons may in some embodiments include raised or recessed
distinctive symbols 92 to allow tactile as well as visual cues to
be used, such as by passengers with low visual acuity.
[0043] Alternate passenger control inputs are likewise suitable for
some embodiments. For example, a control panel 82 embodiment may
use four buttons, as shown in FIG. 6, whereby each diaphragm can be
commanded directly, or whereby a go-to-end command can be input
with a dedicated button. The control panel 82 may be formed at an
angle that eases viewing or access.
[0044] FIG. 7 is a block diagram showing electronic,
electromechanical, and relevant mechanical components of a dual
shade mechanism drive 94 according to the invention. Note that
several of the hardware elements shown in others of the drawings
also appear in FIG. 7. The control panel, referred to in FIG. 7 as
a "PAX (personnel access) switch" 82, provides local interface,
commanding operation via buttons. Electrical connection to the
cassette 10 uses an input connector 96, shown piecewise throughout
FIG. 7, that can accept input power 132, ground return 134, and, in
some embodiments, discrete command inputs 120 such as shade
position, backlight brightness, and the like. Input power for
typical aircraft applications is nominally 28 VDC, with excursions
to 16 VDC and 32 VDC required to be tolerated by flight hardware. A
regulator such as a DC/DC converter 136 in some embodiments accepts
this raw power and produces an output voltage having a level and
degree of regulation suitable for the drive control 122 circuitry
of the apparatus. A further regulator 138 can prepare voltages
suitable for electronic components, shown in FIG. 7 as +5 VDC, and
regulated to other voltage levels, such as 3.3 VDC, in other
embodiments.
[0045] In some embodiments, digital remote command inputs can be
applied, using, for example, a standard serial data transfer
technology such as CANbus (International Standards Organization
standard ISO 11898) to pass commands, for which a CANbus
transceiver 118 is preferred.
[0046] Since some commands can apply to all of the window shade
mechanisms in an aircraft, can be configured to be substantially
identical, and can be configured for simultaneous execution, it may
be preferable in some embodiments to implement a common message
transmission mode such as the CANbus broadcast mode. Broadcast mode
implementation embeds broadcast mode flag bits in commands and is
defined so that received commands carrying such bits may not
require explicit addresses. In some embodiments, certain commands
can be issued that do not require responses by individual units. In
some embodiments, state-of-health inquiries and other messages may
require responses, while other embodiments may support individual
cassettes' initiating communications such as fault condition
reports without first being polled.
[0047] Prevention of high peak electrical current draw in a system
with multiple shade cassettes 10 may necessitate gradual
application of motor power in some embodiments, for which multiple
strategies are available. For example, in one strategy, specific
time delays, associated with individual cassette 10 addresses, can
distribute initiation of motor starting surges to a desired extent
despite using a common start command. In another strategy,
cassettes 10 can be assigned to groups, with the groups commanded
separately, so that multiple, smaller current peaks are demanded.
In still another strategy, initial motor voltage can be ramped up
within each cassette 10 (or, equivalently, a pulse width modulator
drive can use a gradually increasing pulse width and can tap its
power in part from capacitance within each cassette 10), so that
speed increases gradually and inertia-driven peak load is reduced.
Other strategies may be preferred for specific embodiments.
[0048] Within a CANbus or like digital remote command
configuration, individual addressing of each cassette 10 may be
required, for which a variety of addressing systems are possible.
In all schemes described below, an address assigned to a cassette
10 is included as part of a transmitted message, sensed by all
cassettes 10, and recognized by a single cassette 10 having that
address. The one selected cassette 10 processes the message. In
some embodiments, the central system may at some time transmit a
message to each possible address in order to search for
anomalies.
[0049] A representative bus-oriented addressing scheme provides
address selection pins along with any other discrete input signals
120 in the electrical connectors 96, so that an individual cassette
10 has an address determined by jumpers in the mating connector in
its installation location. A similar addressing scheme can include
switches, fusible links, pins to accept discrete jumpers, or the
equivalent built into the cassette 10 in hardware and set
preparatory to installing the cassette 10 at a specific location.
In other embodiments, an address can be written to nonvolatile data
storage (NVMEM 130) within each cassette 10. Each cassette 10 can
include a media access control (MAC) address in addition to or in
place of a location-oriented address within a system. Still other
embodiments can establish addresses using any of a variety of
processes that allow each cassette 10 to determine its location
dynamically within a string of cassettes 10 on a common bus, for
example by a hardware/software bus contention resolution
process.
[0050] CANbus support for bidirectional communication, which in
some embodiments supports interrogating and receiving replies from
individual devices, further allows a central control station for a
zone or an entire aircraft to periodically poll individual
cassettes 10 to ascertain their status. Communication functionality
for CANbus 118 can be embedded in a field programmable gate array
(FPGA) or other control device within each individual cassette
controller 98 to support all functions of both the local control
panel 82 and the bus 118 command structures.
[0051] Commands from a central control station can include multiple
functions specified by the central station. A preferred shade
motion speed or backlight 90 power level, for example, can be
included in a system having central control of multiple possible
values in some embodiments. In such embodiments, level setting
commands broadcast from the central station can adjust a property
for all windows in a series of steps. Similarly, shade height for
one or both of the diaphragms 28 and 30 in the cassettes 10 can be
selectable, with position accuracy limited by the resolution with
which a specific embodiment can detect diaphragm 28 and 30
position. Commands from a central station can include individual or
global disabling or enabling of local control of shades if desired,
without requiring that power be removed from the shades.
[0052] Alternative control methods include provision of dedicated
input pins on the input connector 96. In some embodiments, such
pins may be assigned as remote control inputs, assigned, for
example, to allow a business-class seat to include a built-in
control panel that operates more than one shade. Such a control
function can be assigned a priority, allowing the remote input to
override local control on the cassette 10 itself, but to be in turn
overridden by central station controls. In other embodiments, such
inputs may instead accept analog signal levels for desired
functions. Such inputs can include, for example, a dedicated pin
carrying a light level signal, functioning as a control input or
supplying power directly to the backlight device 90 in each
cassette 10. Another input can be an analog control signal to
select a particular position or rate for one of the diaphragms.
Still another input can be a control signal to disable local
operation.
[0053] Whether controlled using digital or analog commands, the
control functions are applied in a typical embodiment to a
controller 98 housed within each cassette 10. A preferred mounting
location embeds the controller 98 within the cross rail 80,
proximal to the control panel 82, and positioned appropriately with
respect to the connector 96, as shown in FIG. 6. Control functions,
applied to power circuitry (i.e., bidirectional motor controllers)
100, which in some embodiments may be housed within the same device
as the controller 98, actuate the drive motors 24 and 26. In
addition to the control panel 82 and input connector 96 inputs, the
preferred embodiment includes an outboard encoder 102 in the
outboard drive motor 24, and an inboard encoder 112 in the inboard
drive motor 26.
[0054] Drive voltage control 122 for each motor controller 100 can
be implemented as hardware components or as a software-based or
FPGA function within the controller 98. Variable-voltage drive
control 122 can be used as an output to regulate speed of a motor
under load, and thereby to make the speed of individual cassettes
10 relatively uniform. Similarly, position counter 124 and speed
sense 126 functions for the encoders 102 and 112, used as data
inputs for the speed regulation function, can be implemented in
hardware, software, or FPGA functions. Each of these functions can
contribute to allowing shade motion to be highly uniform from
device to device, particularly when a signal such as an internal
crystal clock 128, a master signal such as a periodic transmission
from the CANbus, or the like is used as a reference against which
to compare diaphragm speed. A position counter 124 can be used to
determine location, and can compare its operation to end-of-travel
sensing both to calibrate for absolute position and to detect
incipient failures.
[0055] Additional sensors, provided for the inboard and outboard
diaphragms in the form of top-of-travel detectors 104 and 106,
respectively, and bottom-of-travel detectors 108 and 110,
respectively, shown in FIG. 4, are summarized as limit switches
104, 106, 108, and 110 in FIG. 7.
[0056] Sensor technology in some embodiments uses shared-housing
optical transmitter-receiver sensors 104, 106, 108, and 110, shown
physically in FIG. 4. In some such embodiments, light from a light
emitting diode (LED) or laser transmitter within the sensor bounces
off the surface of the intended diaphragm 28 or 30 and strikes a
receiver within the sensor, when the diaphragm is present at that
end of travel. The light fails to be reflected, and is diffused,
when the diaphragm is absent. Optical detectors in other
embodiments can use an optically reflective surface at the distal
wall 114 of the sensor zone, shown in FIG. 5 for diaphragm 28, so
that the presence of the diaphragm 28 blocks a transmitted beam
from reaching a receiver in a housing shared with the transmitter.
Separate transmitter and receiver devices on opposite sides of a
diaphragm may likewise be preferred for still other embodiments, as
may acoustic, ferromagnetic, capacitive, or other non-contact
physical phenomena for position or end-of-travel detection. In yet
other embodiments, contact-based detection may be preferred, or use
of a detection process such as application of motor power without
motor motion (i.e., stalling) to detect that end of travel has been
reached without using separate end of travel sensors. A stall-type
function combined with end of travel sensing can be used to detect
some failures.
[0057] As shown in FIG. 4, two sensors, a first one 108 at the
cross rail 80 end of the cassette 10 and a second one 104 near the
drive mechanisms, are used for the outboard diaphragm 28, and
another two, 110 and 106, respectively, for the inboard diaphragm
30, in some embodiments. In such embodiments, the presence of a
diaphragm, sensed by the sensor nearest the cross rail 80, shown in
FIGS. 4 and 6, indicates that a diaphragm is fully inserted, while
sensing the absence of a diaphragm by the corresponding drive-end
sensor indicates that that diaphragm is fully withdrawn.
[0058] The outboard motor encoder 102 allows the outboard diaphragm
motor 24 angular position to be detected. Since the motor 24 is
positively coupled to the diaphragm 28, a signal from the encoder
102 is directly associated with outboard diaphragm 28 position and
rate. An equivalent arrangement allows an inboard motor encoder 112
on the inboard diaphragm motor 26 to detect position and rate for
the inboard diaphragm 30.
[0059] Absent reception of a CANbus input, the main controller 98
in some embodiments scans the passenger switch (control panel 82)
and the discrete inputs 120 at periodic intervals, such as every
0.1 seconds, to detect commanded position changes for the window
shades. When a position change request is sensed, whether by CANbus
message, by control panel switches 86 and 88, shown in FIG. 4, or
by discrete inputs 120, the main controller 98 provides an up/down
signal to a motor controller 100 to start shade motion.
[0060] During shade movement, the main controller 98 also senses
signals from position counters 124, whereby the main controller 98
can determine if the shade has reached a CANbus commanded position,
and can acquire data for performing functions such as speed
correction.
[0061] The speed correction function is accomplished by comparing
position counter 124 value change versus elapsed time, using a time
reference such as a countdown function in the main processor 98,
regulated by a crystal-stabilized oscillator 128. In some
embodiments, a motor control signal 140 to the affected motor
controller 100 can be removed briefly at short intervals in all
modes of operation. The intervals can be increased, for example, if
the affected speed sense 126 runs slow, compensating for a
reduction in net motor speed. This form of pulse width modulation
effectively changes the average DC voltage applied to the motor,
and thus provides variable motor speed. A calibration discrepancy,
such as inability to set a desired rate or detection of an
unexpectedly large or small encoder pulse count in an end-to-end
traverse, can be an early failure signal, and can be reported in
CANbus status polling replies in some embodiments.
[0062] The main controller 98 may, in some embodiments,
periodically or after detection of imminent power loss, for
example, store data describing the shade position using nonvolatile
memory 130 such as flash memory, so that shade positions may be
recalled after restoration of power. In other embodiments, it may
be preferable for the main controller 98 to command one or both
diaphragms to move successively to one or both ends of travel in
order to sense position, and to thereupon return the diaphragms to
a default position or to their respective initial positions. Each
of these and other control routines may be preferable in some
embodiments. Detection of end-of-travel events can allow functional
checks such as end-to-end encoder counts to be performed as
background activities and the results thereof stored in nonvolatile
memory 130 during normal operation.
[0063] The above-referenced 0.1-second scan interval for monitoring
button presses is short enough in many embodiments to provide
motion with negligible lag from a user's viewpoint, while
permitting main controller 98 operation to be comparatively slow
and thus low in power consumption and electrical noise generation.
Other scan intervals may be preferred in some embodiments, while
non-scanned control systems, such as interrupt-based or digital
signal processor-based control functions, may be preferred in other
embodiments.
[0064] Interpretations of button press signals to control shade
movement may vary with application preference. For example, in a
basic configuration, each button press may cause motion only as
long as the button is held. Movement of the second shade may be
commanded using the same button after the first shade has reached
its end of travel, either by requiring momentary release of the
button or allowing the button to be held continuously. The same
hierarchy can apply in the reverse direction, normally using a
second button, although successive presses of a single button may
reverse the direction of motion in some embodiments.
[0065] In other embodiments, a single momentary button press may
start the default shade moving, and a subsequent press while moving
can stop that shade. (The default shade from a fully-opened
condition would be the light dimming shade in many embodiments,
while the default shade from fully-closed would be the opaque
shade.) A subsequent press of the button after the default shade
stops can be interpreted as a command for the other shade, even if
the default shade is not at the directed end of travel. By similar
logic, pressing a button after the second shade stops could be
interpreted as a command for the default shade again. The system
can be configured so that, after an elapsed (programmable) interval
with no switch action, the next switch press is interpreted as a
command to the default shade. The press-and-hold functionality can
be superimposed on this function.
[0066] Similarly, a rapid double-press of a button can be
interpreted as a command to move the default shade to its end of
travel, or, if the default shade is already at its end of travel,
to move the non-default shade.
[0067] The apparatus has been demonstrated to have exceptional
durability compared to previous designs, but is still subject to
premature wear if abused. For example, extended cycling of the
mechanism, by way of either substantially continuous run commands
or application of many start-and-stop cycles, may be undesirable. A
programmed function can monitor operation for abuse and disable
operation temporarily. In some embodiments, a fixed or
sliding-window time interval such as two minutes can be
established, and an abuse criterion such as the number of position
counts or motion start events in the interval can be compared to a
reference value. If the count is excessive, local command inputs 82
or discrete inputs 120 can be disabled for an interval, such as
five minutes, sufficient to discourage such activity. CANbus
operation would in typical embodiments be unaffected by this
control. Alternative time intervals and abuse protection methods
may be preferred in various embodiments.
[0068] It may be desirable in some embodiments to provide a manual
override, by which a window shade diaphragm can be moved to block
or pass light without availability of electrical power, for
example, or after a failure in the window shade apparatus. Such a
function can be added to the embodiments described above by adding
a manually operated device capable of moving one or more
diaphragms.
[0069] FIG. 8 is a perspective view of an installation 200 from
inside an aircraft, showing a typical window shade cassette 10
installed behind a cabin frame 202, and including a local control
panel 204.
[0070] FIG. 9 is a perspective view of an installation prepared for
manual override operation 210, showing that removing the panel 204
reveals a spindle 212 into which a tool such as the one shown 214
can be inserted. Rotating the tool 214 causes all diaphragms in the
window shade cassette 10 to be urged upward into a fully open
position.
[0071] FIG. 10 is an exploded perspective view of key components of
a cassette 10 with manual override 220, in which a platform 222 is
shown in a fully lowered position. The spindle 224 includes a drive
gear 226, coupled to a driven gear 228 on the spool 230. Rotating
the spindle 224 causes the spool 230 to draw in left and right
lateral elements 234 and 236, respectively, of a pull cable 232
past left and right lower pulleys 238 and 240, respectively. The
left and right descending parts 242 and 244, respectively, of the
pull cable 232 pass over left and right upper pulleys 246 and 248,
respectively, and the left and right rising parts 250 and 252,
respectively, of the pull cable 232 attach to the platform 222. As
the spindle 224 turns the spool 230, drawing in the pull cable 232,
the two rising parts 250 and 252, respectively, raise the platform
222, drawing with it any diaphragms not already at the top of
travel. Peak force required to move the diaphragms is approximately
bearing, gear, and other friction loss plus the force needed to
overcome the magnetic reaction torque of the unpowered motors 24
and 26, respectively, multiplied by any mechanical disadvantage and
losses in using the sprocket holes in the diaphragms to drive the
motor assemblies.
[0072] The manual override in this embodiment provides at least a
single, unidirectional action, which may be used to comply with
typical flight regulations concerning opening all passenger cabin
window shades during takeoff and landing. The expected use of the
override is a pre-landing opening wherein a shade failure occurred
after takeoff. In some embodiments, disassembly of the cassette 10
may be required to lower the window shades after using the
override. Reversal of platform 222 motion may be possible in other
embodiments using the normal, motor-driven operating mode of the
cassette 10 by repeatedly turning the spindle 224 a small amount
and actuating one of the motors briefly in the downward direction,
or by using that motor to overdrive the override apparatus 220,
provided the motor is operational and the override apparatus 220
has drag low enough not to stall the motor. Use of remote commands
via CANbus to actuate a motor other than the default motor for this
function may be appropriate in some embodiments.
[0073] The above description presents a cassette 10 composed of
multiple separate and unique parts, such as guides/side rails,
panel mounting frames, transparent panels, a cross rail, and a
diaphragm cover. Several of these components may be combined into a
smaller number of components in some embodiments. For example, as
shown in FIG. 6, the panel mounting frames 22 and 78, if merged
with their respective transparent panels 18 and 20, can each form a
single replaceable panel, while in that or another embodiment the
two facing and/or merged panels can be made identical. Similarly,
the two side rails 36 and 38 and the cross rail 80 can be combined
into a single U-shaped assembly. The diaphragm cover 12, likewise,
can be divided into inner and outer halves and merged with the
mounting frames. Since it is preferable for light blocking that the
frame remain opaque and the panels remain transparent, comolding
can be used to further reduce parts count, while self-hinges can
join multiple articulated elements within a molded whole.
[0074] The above description provides a window shade apparatus 10
that moves one or more diaphragms vertically. It is to be
understood that vertical diaphragm movement with the shade
diaphragms moved downward to block light is preferred for some
applications, and resembles the motion typical of manual window
shades in many aircraft types. However, diaphragm movement that is
upward from a diaphragm storage area below the window or that is
horizontal may be more appropriate in some applications, and is
accommodated in the inventive apparatus. It may be preferable in
some embodiments to provide a serpentine or S-curve rather than a
simple arcing curve near the guide rail guide shoe areas 64 and 76,
respectively, in FIGS. 5 and 6, so that the orientation of the
diaphragm cover and the motion of the diaphragm outside the
transparent area are substantially parallel to the plane of the
windows. An entirely flat diaphragm path may be preferable in other
embodiments.
[0075] In another aspect, it may be observed that the above
description provides generally planar transparent panels between
which are located generally straight guide rails and one or more
generally planar and somewhat flexible shade diaphragms.
Alternative embodiments may provide a cassette assembly in the
shape of an arc of a cylindrical shell, including transparent
panels that conform to the curve of the cassette assembly. Between
these panels, shade diaphragms can be moved that are flat and flex
to conform to the curve of the cassette, or that are precurved to
approximate the radius of the cassette, which can reduce friction.
In some such embodiments, the panels and/or diaphragms can have a
cylindrical contour generally conforming to a cylindrical fuselage
shape. In other such embodiments, a spherical shell section, a cone
section, or other panel and/or diaphragm contour may be preferred,
where the housing contour is constrained only by the feasibility of
developing at least one guide path between transparent panels
within which a diaphragm can move. Thus, the term "parallel" is
used herein with respect to each geometry, such as plane,
spherical, cylindrical, and the like, whereby parallel guide slots
are those slots permitting a diaphragm having a particular
curvature to move freely within the slots, providing continuous
light blockage when closed, withdrawing substantially fully from
the window aperture when open, and urged to translate by a pair of
tractive fittings positioned opposite each other proximal to an end
of travel of the diaphragm.
[0076] The straight sprocket coupling shaft shown in the figures
can be flexible, or can be provided with one or more universal
joints or other nonrigid torque transfer mechanisms in the shaft or
within the sprockets, for embodiments such as ones in which the
sprocket pair urging a diaphragm do not rotate about a common axis.
For diaphragm motion along an arc rather than a straight path,
differential sprocket sizing may be desirable, at a limit of which
one or more diaphragms may each have a single sprocket distal to a
pivot. A motor per sprocket may be used in some embodiments,
wherein motor synchronization may be preferred.
[0077] Drive mechanisms are described using sprockets with teeth
engaging rows of holes in diaphragms. In some embodiments, it may
be desirable to provide sprocket teeth that engage the diaphragms
with recesses rather than holes in the diaphragm, whereby there are
no holes passing completely through the diaphragms. Where the
recesses require an offsetting bulge on the diaphragm side opposite
the recesses, this arrangement can require a guide slot profile
that accommodates a nonuniform diaphragm shape. In other
embodiments, drive teeth may be integral with the diaphragms, with
mating recesses provided in the drive sprockets. Still other
positive coupling drive mechanisms may be preferred, such as
continuous-loop bead chains configured as drive belts, bonded to
the diaphragms, and driven by bead chain drive sprockets. In each
of these configurations, as in the above-described configurations,
the diaphragms can be configured to be subjected to substantially
low flexure in operation, and thus neither spooled nor fan-folded,
whereby thickness and weight of the window shade mechanism are kept
low and durability of the apparatus is kept high.
[0078] It is to be understood that a sprocket, as the term is used
herein, may in some embodiments include a plurality of radially
protruding elements generally referred to as teeth, and may in
other embodiments include alternative circumferentially distributed
structures capable of receiving teeth or like protrusions.
Similarly, distinctions between sprockets, gears, and other devices
capable of positive coupling are substantially arbitrary, so that a
gear, for example, may be applied in some embodiments in place of a
sprocket. Likewise, where drive considerations so dictate, an
embodiment may provide engagement elements of a drive coupling that
are not coplanar, but are radially distributed on a cone or another
surface that is not a plane perpendicular to an axis of rotation of
the drive coupling.
[0079] As employed herein, the term "tractionable" refers to
interaction between a medium, which can take the form of a
diaphragm having sprocket holes, for example, and a mechanism, such
as a rotatable, toothed sprocket opposed by a guide shoe. Motion of
the rotatable part of such a mechanism couples to the medium and
induces motion therein. In embodiments such as that shown in FIG.
5, traction between the mechanism and medium is substantially
absolute--i.e., the mechanism and medium couple motion with
negligible loss and cannot experience slippage except after damage
or significant dislocation of the parts. In alternative mechanism
embodiments, such as drive wheels having surfaces with relatively
high coefficients of friction, drive wheels having sufficiently
coarse surface texture to engage a medium with a degree of traction
comparable to but less than that of teeth, and the like, the
coupling between a tractionable region of a medium and a
traction-providing portion of a mechanism may be less than
absolute, resulting in slippage, wear, position uncertainty, and
other deficiencies. Media such as the toothed diaphragm and the
bead chain driven diaphragm described above may exhibit, at the
tractionable interface between the mechanism and the driven
element, coupling comparable to that of a toothed sprocket driving
a diaphragm having a row of holes or recesses that mesh with
sprocket teeth.
[0080] The above description presents a window shade apparatus that
is positioned within the pressurized portion of an aircraft
fuselage, and provides light level reduction only. In some
embodiments, it may be preferable to incorporate the window shade
apparatus into a pressure-carrying window assembly in an aircraft
fuselage, so that the outboard transparent panel is attached and
sealed to the airframe and bears a portion of the pressure
differential between the cabin and the outside air, while the
remainder of the shade apparatus is vented into the cabin and
remains substantially free from stress due to pressure
differentials and aerodynamic forces. In a similar embodiment, a
cassette as described previously can omit the outboard transparent
panel, and can be attached either to the aerostructure--i.e., to an
exterior window assembly or other flight-load-bearing component of
an aircraft--or to an interior panel. In order to establish a low
dust environment in the interior of the cassette in such an
embodiment, the cassette can be sealed to the aerostructure.
[0081] Although an example of the shade assembly is shown using
brushless direct current (DC) motors coupled to the shafts by spur
gears, it will be appreciated that other tractive systems and
rotating-shaft motor styles, such as stepper motors, alternating
current (AC) motors, hollow-shaft and integral-drive-shaft motors,
and linear motors, all of which may be gearless in some
embodiments, can be used. Also, although the shade assembly shown
is useful for large commercial aircraft, shade assemblies in the
same or other sizes can also be used in smaller commercial and
general aviation aircraft. The inventive concept can be applied to
other window shade applications, including other forms of
transportation (rail, bus, automobile, spacecraft, and the like)
and static applications (windows in homes, offices, and
businesses). The concept can be further applied to functions other
than windows, such as apparatus to regulate sunlight levels
admitted through skylights or solar heating processes, apparatus to
regulate radiant heat (infrared light) or ultraviolet light flow in
gas, liquid, or solid chemical processes such as polymerization,
and the like. Selection of conductive, radiopaque, polarizing, or
other specific diaphragm attributes can allow the apparatus to
control passage of electromagnetic energy in radio frequency and
x-ray bands, for example, while use of wave plates can transform
polarization of passed energy.
[0082] The many features and advantages of the invention are
apparent from the detailed specification, and, thus, it is intended
by the appended claims to cover all such features and advantages of
the invention which fall within the true spirit and scope of the
invention. Further, since numerous modifications and variations
will readily occur to those skilled in the art, it is not desired
to limit the invention to the exact construction and operation
illustrated and described, and, accordingly, all suitable
modifications and equivalents may be resorted to that fall within
the scope of the invention.
* * * * *