[0001] This invention relates to a display or indicating device using a disk having contrasting
opposite sides for selective display, in a viewing direction for use in displays or
indicators, and utilizing at least one optic fibre end which is displayed to the viewing
location in one disk orientation, which, in most embodiments corresponds to the display
in the viewing direction of the lighter side of the disk. The viewing direction coincides
with intended viewing locations. In one alternative of the present invention the disk
is designed to obscure a single fibre end in the other position of the disk. In another
alternative of the invention there are two fibre bundle ends and one will be displayed
and one obscured in each position of the disk. In the latter alternative the color
of the light emitted by each fibre end will be chosen having regard to the color of
the side of the disk simultaneously displayed.
[0002] The term 'disk' herein defines a relatively flat body defining a median plane. It
need not be circular. In preferred aspects herein the disk is elongated with parallel
sides and preferably rounded ends.
[0003] By the term 'optic' fibre herein is included a single large fibre or a bundle of
fibres arranged: at one end to receive light from a source, to conduct light to the
vicinity of the disk described herein. In this application there is no discussion
of the disk-remote end of the fibre or the source of illumination, both of which may
be conventional.
[0004] 'Forward' herein is from the device toward the intended viewing location and 'rearward'
is in the opposite direction.
[0005] The type of display device with which the invention is concerned provides a disk
or pattern area from an array of disks for viewing from a viewing location which is
at the centre of possible viewing positions whose locus is a cone with its apex at
the disk or pattern area. The cone need not be a surface of revolution although it
usually will be. The subject display or indicating device will be adapted to rotate
about 180° between limiting positions to display a contrasting pattern areas to the
viewing location in two limiting positions of disk rotation. In the main embodiment
the disk will display a light side in an ON limiting position and a dark side in an
OFF limiting position and in the ON position the light side will be visible due to
reflected ambient light. In addition in the ON position the disk or pattern area will
be adapted to allow the light from an or optic fibre to supplement the reflected ambient
light.
[0006] Such a device is disclosed in European Patent Application 86,401,583.9 filed July
16, 1986, Publication number 0,210.913. (application '913 hereafter). In application
'913 a electromagnetically driven disk rotates on its diameter to display a brighter
or a darker side. An optic fibre end is placed behind the disk which is apertured
so that in its 'ON' attitude the light from the fibre shines through the disk to augment
the effect of the reflected ambient light; while in the 'OFF' attitude of the disk
the disk or an appendage thereof masks the fibre to viewers. A disadvantage of the
apertured disk was that, if near 180° rotation was used, the fibre must be at least
the radius of the disk rearward of it, meaning that the cone of light from the disk
was very small or the aperture must be too large reducing the disk's ambient light
reflectant area. If substantially less than 180° rotation was used special appendages
to the disk had to be provided to mask the fibre to the viewer in the OFF position.
[0007] U.S. Patent 5,055,832 (Patent '832 hereafter) dated October 8, 1991, and commonly
owned with this application overcomes the specified disadvantages of application '913
by providing a contrastingly colored disk rotatable through approximately 180° and
provided with a radially inwardly directed notch extending in from a peripheral edge
to a location near to but on one side of the disk axis. When the lighter side of the
disk was displayed the fibre shone through the inner end of the notch to attract the
viewer's attention. When the darker side of the disk was displayed, the fibre end
was obscured by an area of the disk. The described arrangement of the notch could
be used because the permanent magnet, rotatable with the disk, and driven to cause
such rotation, was located at one axial end of the disk, so that the drive core did
not tend to interfere with disk rotation nor did automatic winding techniques used
for winding the energizing coil for the drive coil, tend to interfere with the fibre
or its mount, thus allowing the use of the centrally directed notch.
[0008] However other disks are driven by a pair of cores having ends displaced transversely
relative to the pivotal axis and acting on a magnet within the plan view area of the
disk itself to rotate the disk through approximately 180°. The construction required
that the one edge of the disk, approximately midway axially therealong, to rotate
past the core and core mounts between limiting positions. An Example of this is shown
in U.S. Patent 4,577,427 dated March 25, 1986 (Patent '427 hereafter) and commonly
owned with the present application. The contents of this patent will be referred to
herein but is incorporated herein by reference. Since one edge of a disk driven by
two cores had to be notched to allow the disk to rotate past the cores and core mounts,
and since the automatic winding techniques were desireable for the cores, a spacing
was required between the core and the optic fibre. Thus the nearly centrally directed
notch could not be used.
[0009] By 'axial end' of the disk it is assumed that the disk dimensions may be referred
to as 'axial, width and thickness' instead of the usual 'length, width and thickness'
and 'axial' means, measured parallel to the disk pivotal axis.
[0010] This invention therefore provides a disk rotatable about 180° between two limiting
position wherein it displays, respectively, its contrasting sides to a viewing location.
An optic fibre is located to be near the outside edge of the disk and rearward thereof
in one of the disk's limiting positions and, near such edge, at one axial end of the
disk. The disk is shaped to obscure such fibre end (to the viewing location) in one
(usually the OFF) position of the disk. On the opposite side of the disk axis at a
location being the mirror image, across the disk axis, of the disk area which obscures
the fibre end, is a cut out forming a continuation of the edge of the disk what allows
the disk, rotating in either direction between limiting positions to pass the fibre
and its mount or support. Since the cores are no closer than midway along the axis
of the disk and the fibre is at one end, there is sufficient spacing for automatic
winding of the cores.
[0011] The 'corner' location of the cut out at one axial end of the disk and at maximum
spacing from the axis has advantages beyond good spacing from the core.
[0012] The notch for passing the fibre mount is to be made as small and preferably as far
from the center as possible since it derogates from the display area and hence the
appearance of the disk. For minimum notch area the notch is preferably defined by
one edge parallel to the rotational axis. The other edge is preferably about 90° thereto.
If the pivotal axis of the disk is at an angle to the perpendicular to the fibre optic
axis the transverse edge will or may be angled to be slightly above or below 90°.
[0013] Preferably for a number of applications, such as bus signs the disk is made longer
in the axial than in the radial direction as best shown in patent '427.
[0014] When the non-notched edge of the disk is covering the fibre end the lighter side
of the disk faces the fibre end. Reflection of the light of the fibre, back from the
disk may with some disk backgrounds create random light reflections for the viewer
and derogate from the appearance of the indicator or display. The area on the lighter
disk side, which receives the disk radiation is therefore sometimes darkened to absorb
the light and absorb such random reflections. This is a reduction of the area of the
bright side of the disk which may be tolerated in some applications.
[0015] The permanent magnet is preferably mounted, within the periphery of the disk in plan
view. The magnet is preferably mounted so that in each limiting position one pole
of the magnet rests close to one of the drive cores. Although the magnetic force,
between the permanent magnet and the drive core will, at adequate spacing, vary inversely
as the square of the distance between them, there is a lower limit to the proximity
to which the magnets may be brought. This is because, with the cores used (although
they are of relatively high remanence) the permanent disk magnet, at a certain proximity,
will overcome the core magnetism and latch to the core. Thus the spacing at a limiting
position must be sufficient to avoid this. (For the wide variations of core materials
and consequent remanent magnetism, and the wide variety of permanent magnets and spacing
this distance must be empirically determined). For tolerance control purposes the
spacing once determined should therefore be maintained by a projection of the core
mount (not the core itself to avoid bringing disk layer thickness into the calculation).
For tolerance control purposes, the fibre end should not be used as a stop. Hence
a means must be provided for locating the fibre end rearward of the disk in that limiting
position where the disk area obscures the fibre.
[0016] In drawings which illustrate a preferred embodiment of the invention.
[0017] Figure 1 is a perspective view from the front of display or indicator elements in
accord with the invention.
[0018] Figure 2 is an end, partially sectional, view of an element of Figure 1.
[0019] Figure 3 is a rear perspective view of a strip of display or indicating elements
as shown in Figure 1.
[0020] Figure 4 is a partial side view of the elements of Figure 1 with some components
missing.
[0021] Figure 5 is a partial end view showing the relation of the magnetic members.
[0022] Figure 6 is a sectional side view showing the relative location of the fibre end
to the other components.
[0023] Figure 7 demonstrates the insertion of a fibre bundle in its mount.
[0024] Figure 8 demonstrates the geometry of the cut-out.
[0025] Figure 9 shows a perspective view from the front of elements each with two fibres.
[0026] Figure 10 and 11 show schematically the disk of Figure 9 in respectively contrasting
orientations.
[0027] Figure 1 shows the frame 10 running longitudinally along direction L and such frame
at each end, in the preferred embodiment, is provided with means defining mounting
grooves 12 which allow a plurality of frames 10 to be mounted side by side on transverse
coupling members received in grooves 12, to form an array. The transverse direction
is indicated by lines T - T. An analogous method of mounting longitudinally extending
display frames is shown in U.S. Pat. No. 3,942,274 dated Mar. 9, 1976 to Winrow although,
in that patent, the transverse grooves are forwardly directed.
[0028] It will be understood that the letters L, T, define a display plane in such a device
and that the perpendicular P to such plane (Fig. 6) is directed toward the viewing
location and is the reverse of the intended viewing direction. When speaking of intended
viewing directions and locations it must be realized that these are in the centre
of a cone of viewing positions which will vary in various applications where within
such cone the display or indicator is clearly displayed.
[0029] It will also be noted that in the preferred (but not all) applications, the disks
are at an angle A to the intended viewing direction so that their pivot axes may overlap.
This angle would normally be between 3° and 10° but will be selected to be small enough
so that the disk faces may be seen from the intended viewing location. For example
if the elements were on a sign over a freeway, the intended viewing direction for
a car driver might be at 5° above the horizontal. Thus the direction P and the direction
of the optic fibres would be at a descending angle of 5° to catch the eye of the motorist
while the angle A° would be (say) 3° below this.
[0030] In the drawings, the frame 10 defines transverse walls 14 at each end and located
between adjacent ones of the longitudinally disposed disks 16. Each transverse wall
14 is provided with a forwardly directed mounting projection 18. Adjacent mounting
projections 18 are provided with facing wells 20 to receive the disk 16 spindles 22.
As best shown in Fig. 4 the facing wells 20 of adjacent projections 20 are displaced
in the forward direction to tilt the disk pivot axis to the vertical a sufficient
degree so that the wells 20 on opposite sides of a projection 18 overlap in a vertical
direction (that is are laterally displaced from each other relative to the row direction).
The wells, as previously explained will normally be displaced to produce an angle
A of the spindle axes to the vertical of about 3°.
[0031] In the preferred form of the invention the disk is of the type disclosed in U.S.
Pat. Nos. 3,871,945 ('945 hereafter) dated Mar. 18, 1975 and (its divisional) 3,953,274
('3274 hereafter) dated April 27, 1976, both commonly owned with this application
and both naming as inventors Winrow et al. The disk is thus made of 3 layers laminated
together, the middle layer is apertured in the shape of and to receive a magnet of
approximately the thickness of such middle layers. It will be obvious that this method
of construction allows the preferred assymetric disposition of the magnet to the extent
desired without inconvenience since the middle layer is merely punched at the selected
location and the magnet inserted during the construction of the disk. In the patented
construction, moreover, the middle layer is shaped to provide projecting spindles
which form the mounting spindles of the disk. (It should be noted that each of the
outer layers may have sub-layers. The outer layer corresponding to the dark side is
usually dark tape thereover to produce the dark outer surface on the ultimate disk.
The opposite side of the disk will customarily have a sub-layer of vinyl colored to
the bright color required and sub-layer being an outer transparent protective casing.
In general however the disk is assembled as a three layer lamination, the myler-dark
covered sub-layers being applied as a single layer to one side of the central layer
and the vinyl-protective covering sub-layers being applied as a single layer to the
other side of the central layer.
[0032] Although the inventive aspects defined herein are suited to the previously patented
laminar disk, it must be emphasized that in the broad aspects of the invention, including
the aspect of tilting the disk axes relative to the row axes and the aspect of stopping
the disk with a contact inward of the disk edge are not limited to use of the patented
disk.
[0033] The disk 14, preferably constructed as defined in U.S. Patents '945 and '3274 comprises
a lamination of three layers. Each of the two layers 24 and 26 may be made from two
sub-layers. The light side layer 24 is usually an inner sub-layer of vinyl colored
for the light color designed with an outer transparent protective sub-layer. The dark
side layer 26 is usually a single layer of tape to provide the dark color. The middle
layer 28 is preferably of mylar to correspond to that of the magnet 30. The mylar
layer has sufficient strength that it supports the extending stub shafts 22 which
are formed as an integral part of the middle layer. The stub shafts 22 may be inserted
in wells 20 by slightly bending the resilient (due to the resiliency of the mylar)
disk to achieve insertion.
[0034] As best shown in FIG. 1 the middle layer 28 is provided with a slot shaped to receive
the permanent magnet 30 which is preferably made of the copper-nickel-iron alloy cunife
magnetized to provide a magnetic axis in the median plane of the disk transverse to
the pivot axis defined by spindles 20. The poles 'N' and 'S' of the permanent magnet
are indicated in the drawings.
[0035] The recess in the middle layer 28 of the disk and the magnet therein are preferably
located so that it is transverse to the pivotal axis and displaced to be all on one
side of the pivotal axis at about the midway point between the stubs 22. On the edge
opposite the outer (here 'N' pole of the magnet) is provided a notch 36 for a purpose
to be hereafter discussed.
[0036] The disk is preferably made longer than it is wide to take advantage of the fact
that in many applications, such as bus signs, there is more available space in the
vertical than in the horizontal dimension so that the height of the disks is increased
to give greater visibility.
[0037] The shape of the disk is a compromise. An oval disk terminating in semicircles at
each end would give a better visual impression than a rectangle for disks collectively
defining a diagonal. However, the oval disk does not use as much of the available
display area as desired. Therefore, the compromise shape with curved end and corners
as shown is used.
[0038] As noted the use of overlapping wells and angled spindles allows more complete use
of the available display space in a row by allowing the disks to be placed more closely
together.
[0039] Actuation for the disk to turn it to one or the other orientation is provided by
a reversible magnetic field forming means, exterior to the disk and acting on the
permanent magnet 30. The exterior field forming means in the preferred embodiment
is provided by a pair of core members 38 of high carbon, steel, having a relatively
high remanence. The core members 38 are fixed in position on each side of the frame
and extend through bores therein to project rearwardly of the frame, as shown and
forwardly to the vicinity of the disk (and magnet) locus when the disk is displaying
one or the other of its contrasting sides in the viewing direction. The molded plastic
frame provides on each side inwardly facing abutments 40 each of which partially surrounds
a core 38 adjacent the core forward end. As shown in FIG. 2 the forward end of each
abutment 40 has a forwardly and inwardly sloping surface which is located forward
of the forward end of core member 38 and provides a pair of stops or knuckles 42 shaped
to contact the disk 16 inwardly of its edge. The disk contacting surface of the knuckles
or stops 42 is as small as possible in humid conditions surface tension will fold
the dot in place if the contact area is too large.
[0040] The contact is made inwardly of the disk 16 edge because the construction of the
disk sometimes leaves a small (not visible) accretion of adhesive or tacky material
at the edge. The inwardly displaced contact does not contact such material and the
risk of the disk sticking is therefore reduced.
[0041] A knuckle 42 stops the disk at a limiting position which is a location spaced from
the core 38 end because it is preferred to use high carbon steel for the pole pieces.
This material, although of relatively high remanence is of lower remanence than some
core materials (such as vicalloy) previously used in controlling display disks. With
the high carbon steel cores 38, therefore, care must be taken that the spacing between
the ends of cores 38 and the permanent magnet 30 of the disk is such that the permanent
magnet cannot alter the magnetic polarization of the core 38 and to cause latching
of the disk. Accordingly, knuckles 42 are shaped to achieve the desired spacing which
will be determined in accord with the cores 38 and magnet 30 used.
[0042] The disk opposite magnet 30 is provided with the notch 36 shaped to clear core 38
and abutment 40 during rotation of the disk.
[0043] It should be noted that, although the spacing of the core end from the magnet in
stopped position is important, this is customarily achieved by measures exterior to
the disk. Preferably during assembly the frame 10 is maintained in a clamp while tooling
associated with the clamp inserts the cores to a stop intrinsic to the tooling and
clamp. The core 38 is then held in place by friction.
[0044] In accord with the novel features introduced by this invention the optic fibre arrangement
in the device will now be discussed. With the exception of the core notch 36 and the
fibre cut-out 110 the disk is preferably symmetrical about the pivotal axis.
[0045] The cut-out 110 is located on the same edge as notch 36 and as far as possible from
the core notch 36 and is thus located at one axial end of the disk. Thus if the disk
were square or rectangular, both of which are within the scope of the invention the
cut-out 110 would be located in a corner of the disk and the position shown is analogous
to the corner given the disks rounded ends.
[0046] A bore 114 in the rear wall of casing 10 is continued on each side of the rear wall
in a forward boss 116 and a rearward boss 118. Since the direction of the optic fibre
is quite important, the bore 114 is a close fit for the fibre ferrule. The optic fibre
122 (which is itself a large bundle of tiny fibres) or may be a single large fibre
particularly if of plastic with suitable optic qualities is covered by a plastic protective
sheath 123 and extends from a light source, not shown, to a metal ferrule which encloses
the bundle leaving its radiation output end 128 open. The ferrule comprises a wider
rearward cylinder 126 and a narrower forward cylinder 124, defining between them the
forwardly facing shoulder 130. The thinner cylinder 124 makes a friction fit with
the walls of the bore 114 and the outer wall 132 of the rear boss acts as a stop for
shoulder 130 to determine the location of the output fibre end 128. The location of
fibre end 128 is not particularly critical but (to avoid acting as a stop for the
disk) it must be rearward of the area 134 (which is a mirror image of the cut-out
110 across the pivotal axis) when area 134 blocks the light from the fibre end 128
in the OFF limiting position. Fibre end 128 must be then rearward of the disk because
disk magnet 30 to core 38 spacing
is critical and this is determined by stops 42 acting on the disk surface.
[0047] The cut-out 110 is dimensioned to allow the light from the fibre end to reach the
viewing location in the ON limiting position of the disk. The notch area is kept to
a minimum because it detracts from the appearance of the dot in the ON position. Thus
in the preferred shape of the cut-out the edge 136 is parallel to the pivotal axis
and the edge 138 is approximately perpendicular thereto. If the display element were
to have the pivotal axis perpendicular to the viewing direction a true perpendicular
edge 138 would be used with the location of edge 138 (as in the preferred embodiment)
chosen to clear the fibre optic and its support when travelling between limiting positions,
and in the ON position to allow passage of the radiation from the optic fibre end
in the desired cone about the viewing direction. (In most cases the specified cone
for the optic fibre used has a 15° included angle, that is a surface of revolution
7 1/2° from the intended viewing axis).
[0048] Where, as here, the pivotal axis of the disk slopes at 3°-10° to the plane L-T of
the array, the edge 138 for a cut-out in the top corner must slope at a little greater
than 90° (see Figure 8) to edge 136 to clear the fibre bundle and mount, and if a
lower corner fibre and cut-out were provided than the edge 138 could be slightly less
than 90° to edge 136 and still clear the fibre end mount and allow passage of the
radiation cone from the fibre.
[0049] The mirror image area 134 of the disk blocks the light from the fibre from the viewer
in the OFF position of the disk. It is found that with certain finishes for the inside
of frame 10 a certain amount of light from the fibre is sometimes reflected from the
lighter side of the disk and then randomly reflected about the disk-wall in casing
10 so that some of this radiation reaches the viewer with a consequent derogation
in the sign appearance. Accordingly the area 134 on the lighter side of the disk,
is preferably provided with a blackened absorbing coating to greatly reduce reflection.
For this purpose the further derogation from the disk appearance in ON position because
of the blackened area is accepted. For specific purposes the blackened area may be
larger or smaller than cut-out 110.
[0050] Cores 38 project rearwardly of the frame and mount energizing windings 46 which magnetize
the cores in the desired polarity. The bridging member 48 of iron having soft magnetic
qualities is attached to the cores 38 rearwardly of windings 46 to complete the magnetic
circuit between the cores 38. Terminal posts 50 are mounted to project rearwardly
from the frame corresponding to each core 38 and designed at their rearward end for
connection to an electrical circuit, not shown. The leads 52 to the windings 46 are
preferably soldered to terminal posts 50 at the latter's rearward end. The windings
46 are connected in series so that energization to the paired terminal posts will
magnetize the paired cores 38 so that one core forward end is north and the other
south. These polarities are simultaneously reversed to rotate the disk.
[0051] The windings 46, and cores 38 are preferably wound by automatic machinery requiring
a minimum radius about each core for the winding head. It is such radius that requires
that the boss 118 for the fibre be as far as possible from the nearest core, in this
case in the 'corner' of the disk for a central core notch. This is also the reason
why the cut-out 110 for the fibre cannot, in any preferred arrangement, be combined
with the core notch. The extended bosses 118 and 116 for the fibre ferrule are, in
turn required to provide a degree of accuracy to the radiation from the optic fibre.
[0052] In other constructions than the 'sandwich dot' of U.S. patents '945 and '3274 the
core could be at one axial end of the disk and the fibre and fibre notch could be
at the other axial end of the disk. However with the sandwich dot, the magnet is dropped
in a well, to be surrounded with a sandwich layer so cannot be too close to a corner.
[0053] The permanent magnet 30 is preferably a relatively flat metal magnet made of cunife
with its magnetic axis and location as indicated. The location and orientation mean
that the radially outward pole 'N' in the drawing is the driven element for operation
of the device while the radially inward pole takes no material part in the operation.
[0054] In many applications it would be adventageous to use a flat magnet with its polar
axis perpendicular to the plane of the disk. However metal magnets are not usually
suitable when so magnetized and plastic magnets may be so magnetized but are too weak
when used with the sandwich dot.
[0055] With the disk axes sloped, as shown in FIG. 4 the assymetric arrangement of the disk,
as shown in FIG. 1 aids in the operation of the disk. As noted, with any of the disks,
a notch and cut-out removed from one side and the magnet is displaced toward the other.
The weight bias in favour of the magnet displacement side together with the axial
tilt assists the disk to start to turn as soon as the core is reversed to release
at from a limiting position. This renders operation of the disk more certain.
[0056] As illustrated in FIG. 5 the permanent magnet 30, in its rest limiting position of
FIG. 2 has its outer edge 31 (corresponding to the N pole) within a 45° truncated
core whose axis is perpendicular to the disk rest position and which expands from
the core end in the direction of the disk. The location of the outermost edge 31 of
the permanent magnet is indicated E the boundaries of the cone, as they appear in
FIG. 5 are defined as CR and CL respectively. It will be obvious that the outer edge
31 of the permanent magnet is well within this cone. The practical result is that
on reversal of the core magnetism the repulsive force from the core on the magnet
is more nearly perpendicular to the disk than parallel, giving a good starting torque
to the disk and avoiding the necessity of providing an extra bias magnet. The cores
38 are of course located so that the same effect occurs when the disk is in its opposite
limiting position to that shown in FIG. 2, that is with the N end of the permanent
magnet to the left and the notch to the right. Obviously the geometrical relationship
will hold true where as shown the cores 38 are symmetrically disposed with respect
to the pivotal axis.
As previously noted the feature just described, and that relating to the stop for
the disk inboard of the disk apply to disks used singly as well as to a plurality
of disks in rows; and both features apply to disks whether or not their pivotal axes
are perpendicular to the viewing direction or at a slight angle to the perpendicular.
[0057] In operation the disk is rotatable approximately 180° between its ON position (with
the notch 36 and cut-out 110 to the left in Figure 1) and OFF position with the notch
and cut-out to the right in Figure 1, rotation being in the sense which moves the
notch 36 and cut-out 110 farthest from the viewing location, i.e. to the rear of the
pivot axis. The cores are magnetized as indicated in FIG. 2 (indicated by the dotted
'N' and 'S'). The fibre ends 128 will each be constantly illuminated. The disk would
have rotated to and remained in the ON position of the middle disk in Figure 1. The
light from the fibre shines through cut-out 110 to capture the attention of the viewer
within a cone about the intended viewing direction. The lighter side of the disk will
be displayed and will usually correspond to the color of the fibre radiation. The
opposite darker side of the disk will usually correspond to the color of the frame
and associated hardware. When windings 46 are energized to reverse the polarity of
the cores the disk, under the control of the radially outward here 'N' pole of permanent
magnet 30 will rotate (counter-clockwise in Figure 2), with the notch passing one
then the other core 38 and its mount and the cut-out passing the fibre top, 128 and
ferrule 124 until the non-notched edge of the disk is resting on the left hand stop
42. The disk is now in the OFF position with the area 134 blocking, to the viewer,
the light from the optic fibre and the dark side of the disk displayed. The disk will
remain in that position until the polarity of the cores is again switched, at which
time it will again rotate to the ON position rotating so that the notch and cut-out
again pass rearward and farthest from the viewer.
[0058] In all aspects of the invention the polarity of the permanent magnet may be reversed
and the operations and advantages will be the same, the positions of the disk being
obtained by opposite magnetizations of the cores.
[0059] As an alternative to the preferred embodiment Figure 9 shows a second optic fibre
with end 128A with supporting boss 116A (aligned rear boss is not shown) the second
fibre has a location at the opposite axial end of the disk and the opposite side of
the pivotal axis from fibre 128 with supporting bosses 116A (rear boss 118 is not
shown) from bosses 116, 118 with an additional cut-out 110A to clear the fibre bundle
and boss 116A. With this arrangement, the disk will display one fibre 128 in one limiting
position and the other fibre 128A in the other limiting position. Thus, for example
(Figure 10) one fibre 128 and its co-displayed side 24 may display red to the viewer
and in the other disk orientation (Figure 11) the other fibre 128A and its co-displayed
disk side 26 green. The array background will have whatever color is most suitable.
The electromagnetic drive will be the same as that described in relation to Figure
1.
[0060] The application has discussed the use of the disk with a 'corner' notch for an optic
fibre in terms of the preferred disk form of patent '427. However many alternatives
are considered within the scope of the invention. As previously stated the axes may
be parallel to the array instead of slanted as in patent '427. The axes may bear any
orientation. The magnetic drive may be different, for example on a magnet or the end
of the disk as in patent '832.
1. Display or indicating device defining a viewing location comprising:
a pivotally mounted disk displaying lighter and darker colors on opposite sides
and rotatable over an approximately 180° range between limiting positions in which
respective ones of said opposite sides are displayed in the viewing direction,
selective moving means adapted to selectively move said disk between limiting positions,
optic fibre mounted on a mount with its end directed approximately in said viewing
direction, and its end just rearward of a first location on said disk, in the limiting
position which displays said lighter side,
said first location being adjacent one edge in said axial direction of said disk
and just inward of the widest radius of said disk,
said disk being provided with a cut-out corresponding to said first location adapted
to avoid said optic fibre and mount in rotating between said limiting positions, and
a second location on said disk located to obscure said fibre end to the viewing
location in the other position of said disk.
2. Display or indicating device as claimed in claim 1 wherein said cut out is defined
by an edge parallel to said axis and an edge at about 90° thereto.
3. Display or indicating device as defined in Claim 1 or 2 wherein said disk is longer
in said axial direction than in a radial direction.
4. Display or indicating device as claimed in any one of the preceding claims wherein
the otherwise lighter side of said disk is darkened in the vicinity of said second
location to reduce reflection therefrom of light from said optic fibre end.
5. Display or indicating device as claimed in any one of the preceding claims wherein
said selective moving means comprises a permanent magnet located on said disk with
its polar axis having one pole remote from said pivotal axis,
a pair of core members located rearwardly of said disk and having energizing windings
and each having a supporting mount,
each of said core members having ends directed generally toward said viewing location,
said core ends being each located to be rearward of the location of said one pole
in one of the limiting positions of said disk,
a notch in the edge of said disk located further from said viewing location in
movement of said disk between limiting positions, and
said notch being shaped to allow rotation of said disk, between limiting positions,
clear of said cores and mounts.
6. Display or indicating device, as claimed in claim 5, wherein stops formed integrally
with said core mounts are provided to limit rotation of said disk at each limiting
position, said stops being located to sufficiently space said core end from said magnet
at each limiting position so that said magnet cannot latch to the adjacent core end.
7. Display or indicating device as claimed in claim 5 or 6 wherein said fibre end is
located to be rearward of said disk when in the limiting position displaying its darker
side.
8. Display or indicating device as claimed in claim 5, 6 or 7 wherein said magnet is
arranged with its polar axis transverse to said axis and said other pole is located
adjacent said pivotal axis.
9. Display or indicating device defining a viewing location comprising:
a pivotally mounted disk displaying contrasting colors on opposite sides and rotatable
over an approximately 180° range between limiting positions in which respective ones
of said opposite sides are displayed in the viewing direction,
means adapted to selectively move said disk between limiting positions,
a first optic fibre mounted on a mount with its end directed approximately in said
viewing direction and its end just rearward of a first location on said disk in one
limiting position,
said disk being provided with a cut-out designed to expose said first fibre end
to the viewing direction in said other limiting position and to allow rotation of
said disk between limiting positions,
a second optic fibre mounted on a mount with its end directed approximately in
said viewing direction and its end just rearward of a second location on said disk
in the other limiting position, and
said disk being provided with a cut-out designed to expose said second fibre end
to the viewing direction in said one limiting position and to allow rotation of said
disk between limiting positions.
10. Display or indicating device as claimed in claim 9 wherein said selective moving means
comprises a permanent magnet located on said disk with its polar axis having one pole
remote from said pivotal axis,
a pair of core members located rearwardly of said disk and having energizing windings,
each having a supporting mount,
each of said core members having ends directed generally toward said viewing location,
said core ends being each located to be rearward of the location of said one pole
in one of the limiting positions of said disk,
a core notch in the edge of said disk located further from said viewing location
in movement of said disk between limiting positions, and
said core notch being shaped to allow rotation of said said disk, between limiting
positions, clear of said cores and mounts.