LCD support bracket

An LCD support bracket formed by a plurality of resilient contilever beams projecting from a support to the lower edge of the LCD panel. The opposite edge of the LCD panel is supported by an elastomeric interconnection member that electrically connects the LCD panel to a circuit board on which the elastomeric interconnection panel is mounted. A cover having a viewing window is placed over the LCD panel to hold the LCD panel in place and to preload the resilient cantilever beams. The upper transparent pane of the LCD panel preferably extends beyond the edge of the lower transparent pane so that the resilient cantilever beams and the elastomeric member compress only the upper pane. As a result, the support bracket does not compress liquid crystal sandwiched between the upper and lower panes.

DESCRIPTION 
1. Technical Field 
This invention relates to liquid crystal displays, and more particularly, 
to a bracket for supporting a liquid crystal display in a manner that 
allows the liquid crystal display to absorb shocks without preempting the 
area beneath the liquid crystal display. 
2. Background of the Invention 
Liquid crystal displays ("LCD's") are commonly used in a wide variety of 
electronic devices to display alphanumeric symbols. LCD's are typically 
fabricated by sandwiching a layer of liquid crystal between a pair of 
transparent panes. The transparent panes are typically glass. Since 
electronic devices using LCD's are sometimes dropped, banged or otherwise 
subject to shocks, LCD's should be shock-mounted so that shocks imparted 
to electronic devices do not break the glass panes in the LCD's. It is 
also important that LCD's be mounted so that their panes are not squeezed 
together too tightly since doing so may force the layer of liquid crystal 
from between the panes in the area where the LCD's are squeezed. 
Furthermore, it is desirable to mount LCD's as described above in a 
relatively inexpensive and compact manner so that the LCD's do not occupy 
an inordinate amount of space in the electronic device. 
In the past, LCD's have typically been mounted in either a fixed bracket or 
in contact with an elastomeric interconnection member. A fixed bracket 
generally includes a groove into which an edge of the LCD is inserted or a 
ledge against which one edge of the LCD is held. Regardless of whether a 
grooved or a ledge is used, the clearance provided for the LCD must be 
sufficient to allow for variations in the thickness of the LCD which 
typically occurs because of inevitable manufacturing tolerances. In fact, 
the thickness variation for relatively inexpensive LCD's used on 
mass-production items such as calculators, can be substantial. The need to 
leave a tolerance for LCD thickness variations normally causes the LCD to 
be somewhat loosely mounted in the fixed bracket. This looseness causes 
the LCD to undergo a sudden deceleration when the electronic device in 
which it is mounted is dropped or otherwise subject to strong shocks. 
Typically, the LCD panel bows in the direction of the shock so that the 
supported edge of the LCD contacts the fixed bracket along a relatively 
sharp corner. Concentrating all of the support for the LCD along a line, 
i.e., the corner of the bracket, causes excessive bending stresses in the 
LCD thereby cracking one or more of the transparent panes of the LCD. 
The use of an elastomeric interconnection member successfully shock mounts 
LCD's so that they are able to withstand shocks induced by dropping or 
banging electronic devices. However, elastomeric devices inherently 
support LCD's from a printed circuit board directly beneath the supported 
edge of the LCD. For this reason, they preempt space on the circuit board 
that could be used to mount components. This limitation can be very 
important in miniature devices in which available circuit board spaces is 
at a premium. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide a support bracket for a liquid 
crystal display that allows the liquid crystal display to absorb shocks 
imported to electronic devices in which the liquid crystal display is 
mounted. 
It is another object of the invention to provide a support bracket for a 
liquid crystal display that does not preempt the space beneath the liquid 
crystal display. 
It is still another object of the invention to provide a support bracket 
for a liquid crystal display that is compact and relatively inexpensive. 
It is a further object of the invention to provide a support bracket for a 
liquid crystal display that is capable of supporting the liquid crystal 
display against movement in all directions. 
These and other objects of the invention are provided by a bracket for 
supporting a liquid crystal display within a cutout formed in a generally 
planar support. The bracket includes a plurality of spaced apart resilient 
cantilever beams extending from the support along a longitudinal axis that 
is generally parallel to the plane of the LCD panel into the cutout to 
support the LCD. The LCD is also supported at least one other location. 
Finally, the surface of the LCD that is opposite the surface contacted by 
the resilient cantilever beams is biased against the cantilever beams to 
preload the cantilever beams, thereby shock mounting the LCD. Each of the 
cantilever beams preferable terminates in a support foot projecting toward 
and contacting the LCD. Each of the support feet preferably has a rounded 
end so that there are no sharp corners for the LCD to contact. The LCD 
preferably has one of its two transparent panes projecting beyond the edge 
of the other transparent pane with the resilient cantilever beams gripping 
only the projecting transparent pane. As a result, the resilient beams 
cannot compress a layer of liquid crystal sandwiched between the first and 
second transparent panes. The ends of the resilient beams preferably 
contact the edge of the recessed pane, thereby restricting movement of the 
LCD in a direction that is parallel to the plane of the LCD.

DETAILED DESCRIPTION OF THE INVENTION 
One embodiment of the inventive LCD support bracket is shown in FIGS. 1 and 
2 as part of a hand-held electronic multimeter 10. As is well known in the 
field, the electronic multimeter 10 is used to perform a variety of 
electrical measurements, such as measuring voltage, current, resistance, 
capacitance and the like. The multimeter 10 includes a printed circuit 
board 12 of generally rectangular configuration which is fastened to a 
generally rectangular support 14. The circuit board 12 and support 14 are 
enclosed by a generally rectangular cover 16. The cover 16 has formed 
therein a rectangular opening 20 through which an LCD panel 22 may be 
viewed. The LCD panel 22 is of the type having a layer of liquid crystal 
(not shown) sandwiched between first and second transparent panes 24, 26, 
respectively. The LCD panel 22 is mounted on the support 14. More 
specifically, the edge of the LCD panel 22 facing away from the end 28 of 
the support 14 is carried by a plurality of resilient cantilever beams 30 
projecting from the support 14 horizontally in the plane of the LCD panel 
22. The opposite edge of the LCD panel 22 is supported by a conventional 
elastomeric interconnection member 34 that is positioned within a housing 
36 formed at the upper end of the support 14. 
With further reference, now, to FIG. 3, each resilient cantilever beam 30 
terminates in a support foot 40 projecting upwardly to contact the 
underside of the upper transparent pane 24. The cover 16 contacts the 
upper surface of the transparent pane 24 along its entire parameter and 
forces it downwardly to bend and thus preload the resilient cantilever 
beams 30, as best illustrated in FIG. 3. As a result, the inventive 
bracket grips only one transparent pane 24 of the LCD panel, thus making 
is impossible for the liquid crystals sandwiched between the two panes 24, 
26 to be compressed by the bracket. By avoiding compression of the liquid 
crystal, the performance of the LCD panel 22 is enhanced and it is less 
likely to be damaged during use. 
As also best illustrated in FIG. 3, the end of each resilient beam 30 is 
spaced apart from the adjacent edge of the lower transparent pane 26. As a 
result, the resilient beam 30 prevents the LCD panel 22 from moving to the 
right as illustrated in FIG. 3. In this manner, the resilient beams 30 
restrict the movement of the LCD panel 22 in a plane that is parallel to 
the LCD panel 22. 
The LCD panel 22 is restricted from movement in other directions that are 
parallel to the plane of the LCD panel 22 by locator ribs 46 (FIG. 1) 
projecting downwardly from the cover 16 around the periphery of the 
opening 20. 
As best illustrated in FIG. 3, since the resilient beams 30 extend from the 
support 14 horizontally, i.e. generally parallel to the plane of the LCD 
panel 22, the area beneath the supported edge of the LCD panel 22 is not 
preempted by any downwardly extending support structure. As a result, 
integrated circuit 50 can be mounted on the circuit board 12 in the area 
beneath the supported edge of the LCD panel 22. The area beneath the other 
supported edge of the LCD panel 22 is, of course, preempted by the 
elastomeric interconnection member 34. However, the area of the circuit 
board 12 beneath the other edge of the LCD panel 22 is preempted anyway by 
the plurality of terminals 54 (FIG. 1) that must be connected to the LCD 
panel 22 by the elastomeric interconnection member 34. The inventive 
bracket thus maximizes the use of the space on the printed circuit board 
for electronic components. 
It is important that the LCD panel 22 be supported over a relatively large 
area. In particular, it is important that the LCD panel 22 not be 
supported by any sharp surfaces, such as by a relatively thin edge or 
corner of a support structure. For this reason, the upper end of the 
support foot 40 is preferably rounded as illustrated in FIG. 3. As a 
result, even if the LCD panel 22 bows inwardly in response to applied 
shocks or other forces, it will always contact a relatively large surface 
of the resilient cantilever beam 30. If the upper surface of the support 
foot 40 was flat, then the LCD panel 22 would contact the inner edge of 
the support foot 40 which, being a corner, has a relatively small area. 
Although the embodiment of the inventive bracket illustrated in the drawing 
utilizes four resilient cantilever beams 30, it will be understood that 
greater or fewer beams may be used. However, the minimum number of beams 
can be used is two, and they must be spaced apart from each other on 
opposite sides of the LCD panel 22. The use of four or more resilient 
cantilever beams 30 distributes the LCD support forces over a greater area 
and thus minimizes the force that each beam must exert on the LCD panel 
22. 
The support 14 may be fabricated of a variety of materials as long as it is 
resilient and has suitable stress relaxation properties to retain its 
resiliency for a substantial period of time. One suitable material for the 
support 14, as well as the cover 16, is a polycarbonate such as GE Lexan 
141 or Mobay-Merlon M40 plastic. 
It is also preferable that the force exerted on the LCD panel 22 by the 
resilient cantilever beams 30 be approximately equal to the force exerted 
on the LCD panel 22 by the elastomeric interconnection member 34. By 
balancing the forces exerted on each side of the LCD panel 22, shocks are 
imparted to the LCD panel 22 equally on each side of the panel 22. 
It is thus seen that the inventive LCD support bracket provides a compact 
and inexpensive structure for supporting an LCD panel without preempting 
circuit board space beneath the panel and in a manner that allows the LCD 
panel to absorb shocks during use.