LIGHTING DEVICE FOR TELETYPEWRITERS AND OFFICE MACHINES

APPAREIL D'ECLAIRAGE POUR TELESCRIPTEURS ET MACHINES DE BUREAU

English Abstract

ABSTRACT OF THE DISCLOSURE
A lighting device for illuminating the printing area
of teletypewriters and other office machines has a printed circuit
board clad on one side for receiving a pair of spaced fluorescent
lamp sockets for holding a fluorescent lamp on the insulated side
of the circuit board. On the clad side of the circuit board a
conductor surface is printed which functions as the firing strip
for the fluorescent lamp and is disposed opposite to the area on
the insulated side of the board occupied by the fluorescent lamp.
The entire circuit board assembly is mounted in the teletypewriter
or other machine to be illuminated.

Claims

WE CLAIM AS OUR INVENTION
1. A lighting device for holding and energizing a standard
fluorescent lamp for illuminating the printing area of teletypewriters
and office machines comprising:
a printed circuit board which is clad on one side and
insulated on an opposite side;
a pair of spaced fluorescent lamp receiving sockets
mounted on the insulated side of said printed
circuit board for receiving said fluorescent
lamp, said lamp sockets each having soldered-in
contact springs; and
a conductor surface on the clad side of said printed
circuit board functioning as a firing strip for
energizing the fluorescent lamp, said conductor
surface being disposed on said clad side of said
circuit board in an area opposite to the area
occupied by said fluorescent lamp on the insulated
side of said circuit board.
2. The device of claim 1 wherein said printed circuit
board has a plurality of recesses for receiving a like plurality
of detents integrally formed on a housing of said teletypewriter
for mounting and locking said printed circuit board in said housing.
3. The device of claim 1 further comprising a pair of
snap locks carried on said circuit board for respectively receiving
and locking said fluorescent lamp sockets and wherein said soldered-
in contact springs extend through said circuit board.
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Description

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BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to lighting devices for
illuminating the printing area of teletypewriters and other office
machines, and in particular to such a device employing a fluorescent
lamp.
Description of the Prior Art
The use of various types of lamps disposed in the housing
or casing cover of teletypewriters and other office machines is known
in the art for illuminating the printing area of such machines. Such
lamps have previously employed commercially standard sized lamp
sockets which are clamped or otherwise mounted inside the cover of
the machine, and the associated wiring is similarly clamped inside
the cover. It is kno~in to employ fluorescent lamps as the source of
illumination for such office machine lighting devices, whereby
specially constructed fluorescent lamps having firing strips vaporized
on the lamps are customarily used. Metal casings have also been used
to contain standard lamps. Such special fluorescent lamps are
relatively expensive and standard lamps with commercially sized
lamp sockets in metal casings occupy a relatively large amount of
space.

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SUMMARY OF THE INVENTION
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It is an object of the present invention to provide a
fluorescent lamp holding device for illuminating the printing area
in teletypewriters and other office machines which permits the use
of standard fluorescent lamps as weIl as having small external
measurements so as to occupy a minimum amount of space.
The above object îs inventiveIy achieved by the use of a
printed circuit board which is clad on one side and insulated on
the opposite side. The insulated side of the board receives a pair
of spaced fluorescent lamp sockets and the conductor side of the
board in the region thereof opposite the region occupied by the
fluorescent lamp on the insulated side of the board, has a conductor
surface which functions as the firing strip for the fluorescent lamp.
In a preferred embodiment of the invention, the laminated
printed circuit board has a number OL recesses for receiving tabs
or lugs which are part of the teletypewriter housing for mounting
and locking the printed circuit board with the fluorescent lamp
held thereon in the machine casing.
The lighting device constructed in accordance with the
inventive concept disclosed herein permits the use of standard
home fluorescent lamps in the housing of the teletypewriter or
other office machine. The recesses in the printed circuit board
permit easy installation and removal of the entire circuit board
assembly, including the fluorescent lamp held thereon, and moreover
the entire assembly has relatively small external dimensions so as
to occupy a minimum amount of space.
DESCRIPTION GF THE DRAWINGS
Fig, 1 is a plan elevational view of a lighting device
construct~d in accordance with the principles of the present invention.
Fig. 2 is a side view of the device shown in Fig. 1.

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DESCRIPTION OF THE PREFERRED EMBODIMENTS
A lighting device for illuminating the printing area of
a teletypewriter or other office machine is shown in Figs. 1 and 2.
The device has a printed circuit board 5 which is printed on one
side and insulated on the other side. A pair of conventional
fluorescen~ lamp sockets 2 are mounted in spaced relation on the
insulated side of the circuit board 5 for receiving a standard
fluorescent lamp 1 therebetween. A firing strip 7 for the fluorescent
lamp 1 is disposed on the opposite side of the printed circuit board
5 in the area opposite to the area on the insulated side of the board
5 which is occupied by the lamp 1. ~uring assembly of the device
shown in Figs. 1 and 2, the contact springs 6 of the sockets 2 are
inserted into the printed circuit board 5 and the lamp sockets 2
are locked on the board 5 by snap connections 4 and are electrically
connected to appropriate runs on the clad side of the board 5 by
any suitable solder flow method such as the Schwall method. A com-
mercially sized fluorescent lamp 1 is inserted between the lamp
sockets 2, turned radially, and thus locked in the sockets 2.
In addition to the lamp sockets 2 and the fluorescent
lamp 1, a plug connector 8 is disposed on the insulated side of the
circuit board 5, from which plug 8 all electrical connections neces-
sary to operation of the fluorescent lamp 1 lead by means of ribbon
lines. These connections include, among others, a connection to a
fluorescent lamp ballast (not shown). This fluorescent lamp ballast,
upon activation of a switch for energizing the lamp 1, energizes the
fluorescent lamp via the firing strip 7 which is protected from
contact on the backside of the printed circuit board parallel to the
fluorescent lamp.
The entire 12mp structure is mounted and locked in the
housing or cover of the machine to be illuminated by a number of
recesses 10 in the circuit board 5 which receive a like number of

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detents 9 which are integrally formed on the cover or housing of the
machine, and no further fastening means are necessary.
It will be apparent to those skilled in the art that other
embodiments employing the inventive concept disclosed herein are
possible such as, for example, the contact springs 6 which are
soldered to the circuit board 5 may be shaped with a flange or the
like so that the lamp sockets are held in the printed circuit board
without the use of the snap connections 4. The printed circui~
board may of course be screwed to the housing of the machine to be
illuminated in place of the use of the detents 9 and the recesses 10.
Moreover, depending upon the size of the area to be illuminated,
the circuit board 5 could be lengthened to accommodate a longer
fluorescent lamp 1 in which case the firing electronics for the
fluorescent lamp 1 could be entirely mounted on the printed circuit
board 5.
Th~ lighting device described above permits the use of
a standard 1uorescent lamp for illuminating teletypewriters and
other office machines and permits mounting of the device in the
housing of the machine in such a manner as to signîficantly conserve
space and weight by a screwless snap connection to the housing of
the machine.
Although modifications and changes may be suggested by
those skilled in the art it is the intention of the inventors to
embody within the patent warranted hereon all changes and modifica-
tions as reasonably and properly come within the scope of their
contribution to the art.