[0001] This invention relates to a magnetically operated display.
[0002] Eye-catching displays are becoming more and more popular due to increasing consumerism
and the desire for public awareness of products, public announcements etc.
[0003] A first conventional display includes a matrix of light emitting diodes (LEDS) wherein
various groups of the LEDS in the matrix can be selectively turned on simultaneously
to present various images. The first conventional display performs well in an environment
with a low level of light. However, the efficiency of the first conventional display
is considerably reduced if the level of light is increased, for example, a sunny day,
and the noticeability of the display is impaired.
[0004] A second conventional display includes a matrix of magnetically operated display
units each including a magnet embedded in a pivotable plate including a first surface
with a color different from that of the remaining portion thereof and a second surface
with a color identical to that of the remaining portion thereof. The second surfaces
of different groups of the pivotable plates in the matrix are selectively exposed
to view so as to show different images. The second conventional display shows clear
images in a bright environment, however, visibility of the first surfaces of the pivotable
plates is greatly reduced in the dark as the first surfaces of the plates do not produce
light.
[0005] It is the primary objective of this invention to provide a magnetically operated
display unit which presents clear images in the darkness or in bright sunlight.
[0006] The magnetically operated display unit includes a frame with a color, a plate pivotably
mounted on the frame and including a first surface with a color different to that
of the frame and a second surface with a color identical to that of the frame, a magnet
embedded in the plate, a U-shaped ferromagnetic element mounted on the frame so that
two tips of the magnet are located between two tips of the U-shaped ferromagnetic
element, a solenoid mounted on the U-shaped ferromagnetic element and a light emitting
diode mounted on the frame. The plate defines a cutout for receiving the light emitting
diode and one of the tips of the U-shaped ferromagnetic element. The light emitting
diode includes a tip located on a level between the plate and the tips of the U-shaped
ferromagnetic element. Two opposite currents are selectively directed through the
solenoid.
In the drawings:
FIG. 1 is a perspective view of a magnetically operated display.
[0007] FIG. 1 shows a magnetically operated display unit 2 including a frame 4 including
a base 6 defining five apertures (not shown). Two ferromagnetic rods 8, two ferromagnetic
pins 10 and a light emitting diode (LED) 12 are correspondingly inserted through the
apertures defined in the base 6. Each of the ferromagnetic rods 8 includes a lower
tip and an upper tip. The LED 12 includes two leads 13. A wire 14 is sequentially
wound around the ferromagnetic rods 8 so that a solenoid 16 is formed on each of the
ferromagnetic rods 8. The wire 14 includes two ends each soldered to a corresponding
one of the ferromagnetic pins 10. The lower tips of the ferromagnetic rods 8 are linked
to each other by means of a ferromagnetic strip 17 so that the ferromagnetic rods
8 and the ferromagnetic strip 17 form a U-shaped ferromagnetic element. Each of the
ferromagnetic pins 10 can be inserted into a socket (not shown) so that the magnetically
operated display unit can be connected with a circuit 18. The LED 12 is also connected
with the circuit 18.
[0008] Two arms 20 project upwardly from the frame 4. Two fingers 21 project upwardly from
each of the arms 20. Each of the fingers 21 includes an inner face opposite to the
remaining one of the fingers 21. A bulbous portion is formed on the inner face of
each of the fingers 21 near a tip thereof thereby defining a narrow entrance to a
recess defined between the two fingers.
[0009] A plate 22 includes a color identical to that of the frame 4. Two axles 24 project
from the plate 22 in two opposite directions. Each of the axles 24 is pushed past
the tips of the fingers 21 projecting from a corresponding one of the arms 20 so that
each of the axles 24 is retained between the fingers 21 projecting from a corresponding
one of the arms 20. Thus, the plate 22 is pivotably mounted on the frame 4. A magnet
26 includes a north pole at a tip and a south pole at an opposite tip. The magnet
26 is embedded in the plate 22. The tips of the magnet 26 are located between and
in line with the upper tips of the ferromagnetic rods 8. The plate 22 defines a cutout
28 through which the upper tip of one of the ferromagnetic rods 8 and the LED 12 are
inserted.
[0010] A reflector 30 includes a color different from that of the plate 22. The reflector
30 is adhered to the plate 22. The reflector 30 defines a cutout 32 through which
the upper tip of one of the ferromagnetic rods 8 and the LED 12 are inserted. The
reflector 30 conforms in profile to the plate 22.
[0011] The circuit 18 includes a first switch SW1, a second switch SW2 and a third switch
SW3. The first switch SW1 is connected with an end of the wire 14. The second switch
SW2 is connected with the remaining end of the wire 14. The third switch SW3 is connected
with the LED 12. Each of the switches SW1 and SW2 can be turned between a ground electrode
and a positive electrode.
[0012] As shown in FIG. 1, the first switch SW1 is turned to the positive electrode and
the second switch SW2 is turned to the ground electrode so as to direct a current
through the solenoids 16 in a first direction, thus producing a first magnetic field
between the upper tips of the ferromagnetic rods 8. Then, both of the switches SW1
and SW2 can be turned to the positive electrode or the ground electrode whilst the
first magnetic field remains.
[0013] The first switch SW1 can be turned to the ground electrode and the second switch
SW2 is turned to the positive electrode so as to direct a current through the solenoids
16 in a second direction opposite to the first direction, thus producing a second
magnetic field between the upper tips of the ferromagnetic rods 8. The direction of
the first magnetic field is opposite to the direction of the second magnetic field.
Then, both of the switches SW1 and SW2 can be turned to the positive electrode or
the ground electrode whilst the second magnetic field remains.
[0014] As mentioned above, the first magnetic field or the second magnetic field is produced
between the upper tips of the ferromagnetic rods 8, therefore the plate 22 to which
the magnet 26 is attached is turned between two opposite positions.
[0015] The third switch SW3 can be turned on so that LED 12 emits light. The LED 12 includes
an upper tip which should be located above the combination of the plate 22 and the
reflector 30 so that the LED 12 is clearly visible. The upper tip of the LED 12 should
be located below the upper ends of the ferromagnetic rods 8 so that the combination
of the plate 22 and the reflector 30 will not be hindered by means of the LED 12 when
the combination of the plate 22 and the reflector 30 is pivoted to a position opposite
to the position as shown in FIG. 1.
[0016] The ferromagnetic rods 8 and the ferromagnetic strip 17 can be replaced with a one-piece
U-shaped ferromagnetic element (not shown).
[0017] If the magnetically operated display unit 2 is used in a vehicle (not shown), a transparent
panel (not shown) is located in front of the magnetically operated display unit 2.
When the vehicle is driven, there will friction between air and the transparent panel
thus resulting in a static charge in the transparent panel. The combination of the
plate 22 and the reflector 30 is pivoted when it is in use thus resulting in a static
charge in the magnetically operated display unit 2. The static charge produced in
the transparent panel and the static charge produced in the magnetically operated
display unit 2 will attract each other thus causing difficulty for the pivoting of
the combination of the plate 22 and the reflector 30. Thus, the static charge produced
in the magnetically operated display unit 2 should be removed. A conductive agent
is added in plastic from which the frame 4, the plate 22 and the reflector 30 are
made so that frame 4, the plate 22 and the reflector 30 are conductive to a limited
extent for releasing the static charge to the leads of the LED 12 for removing the
static charge.
1. A magnetically operated display unit comprising a frame with a color, a plate pivotably
mounted on the frame and including a first surface with a color different to that
of the frame and a second surface with a color identical to that of the frame, a magnet
embedded in the plate, a U-shaped ferromagnetic element mounted on the frame so that
two tips of the magnet are located between two tips of the U-shaped ferromagnetic
element, a solenoid mounted on the U-shaped ferromagnetic element and a light emitting
diode mounted on the frame, the plate defining a cutout for receiving the light emitting
diode and one of the tips of the U-shaped ferromagnetic element, the light emitting
diode including a tip located on a level between the plate and the tips of the U-shaped
ferromagnetic element, two opposite currents selectively directed through the solenoid.
2. A magnetically operated display unit according to claim 1 wherein the U-shaped ferromagnetic
element includes two ferromagnetic rods connected with each other by means of a ferromagnetic
strip.
3. A magnetically operated display unit according to claim 2 including two solenoids
each mounted on a corresponding one of the ferromagnetic rods.
4. A magnetically operated display unit according to claim 3 wherein the solenoids are
different portions of a wire.
5. A magnetically operated display unit according to claim 4 including two pins attached
to the frame, each of two ends of the wire soldered to a corresponding one of the
pins.
6. A magnetically operated display unit according to claim 1 wherein the frame includes
a base defining two apertures through each of which a corresponding one of two tips
of the U-shaped ferromagnetic element is inserted.
7. A magnetically operated display unit according to claim 1 including a reflector attached
to the first surface of the plate, the reflector including a color different to that
of the frame.
8. A magnetically operated display unit according to claim 1 wherein the frame and the
plate are made of plastic added with conductive agent so that the frame and the plate
are conductive to a limited extent.
9. A magnetically operated display unit according to claim 1 including two arms projecting
upwardly from the frame and two fingers projecting upwardly from each of the arms,
each of the fingers including an inner face opposite to the remaining one of the fingers
and a bulbous portion formed on the inner face thereof near a tip thereof thereby
defining a narrow entrance to a recess defined between the two fingers.