Ergonomic printer for use in aircraft cockpits

An ergonomic printer suitable for use in an aircraft cockpit includes a polarizing arrangement preventing a paper roll being inserted in a support the wrong way around and a paper extraction arrangement which operates on the paper roll in a region thereof substantially opposite an access orifice. The paper extraction arrangement is associated with a guide arrangement for feeding the paper successively to a feed device, a print station and an outlet slot in a front wall of the printer. The printer may be flush-mounted in a wall of the cockpit of an aircraft.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention concerns an ergonomic printer which can be used in 
the cockpit of an aircraft, for example. 
2. Description of the Prior Art 
Printers are increasingly used for pilot/onboard computer dialogue in 
aircraft. 
The printer is used to print messages or diagrams (a flight plan or a map, 
for example) without disturbing the information shown on the cockpit 
displays. 
Conventional printers require complex operations that are difficult for a 
pilot seated at the controls of an aircraft who rarely has both hands free 
at the same time. 
This is particularly so in the case of operations to load and unload the 
printer and to clear a paper jam. 
The paper used in this type of printer is in the form of a continuous roll. 
To load the printer the paper roll must be inserted into a magazine and its 
free end must be correctly inserted into the feed and guide system which 
passes the paper into the printing area of the printer (the area in which 
a print head moves). 
This loading operation, which requires the use of both hands, is made all 
the more difficult in that the end of the roll is rarely cut off straight 
and is frequently torn and ragged. 
The introduction of this ragged edge into the access orifice of the guide 
system (usually a narrow slot) is therefore particularly difficult. 
A particular object of the invention is to eliminate these drawbacks by 
providing a printer whose design and operation are specifically conceived 
so that all operations, including loading and clearing of jams, can be 
carried out with one hand only and engage the attention of the pilot for 
only a very short time. 
SUMMARY OF THE INVENTION 
The present invention consists in an ergonomic printer suitable for use in 
the cockpit of an aircraft comprising, delimited by a support structure, a 
magazine adapted to contain a roll of paper and comprising means for 
supporting said roll which enable it to rotate freely about a 
predetermined axis, said roll being inserted into said magazine through an 
access orifice in a front wall of the printer through which rolls can be 
moved in translation whilst remaining in a position substantially parallel 
to said axis, the printer comprising polarizing means preventing said 
paper roll being inserted in said support means the wrong way around and 
paper extraction means which operate on said paper roll in a region 
thereof substantially opposite said access orifice, said paper extraction 
means being associated with guide means for feeding said paper 
successively to a feed device, a print station and an outlet slot in said 
front wall, near the access orifice, said outlet slot possibly comprising 
paper cutting means. 
The extractor means advantageously comprise a deflector whose anterior edge 
bears on the paper roll along a generatrix thereof. In this case, contact 
is maintained between this edge and the paper roll during unwinding: 
either by providing means for enabling movement in translation of the paper 
roll so that it is located against said edge by its own weight, 
or by using an elastically deformable deflector. 
The guide means associated with said deflector may comprise a first guide 
plate aligned with the deflector and a second guide plate constituting the 
bottom of the magazine, for example, the second plate delimiting with the 
combination of the deflector and the first plate an intermediate space of 
decreasing thickness in which the paper moves. 
The drive means may comprise a conventional capstan roller driven by a 
stepper motor and directly associated with a print head (a thermal print 
head, for example). 
The access orifice to said paper magazine is advantageously closed by a 
hinged lid which delimits at least partly the slot and which cooperates 
with a microswitch and the printer comprises advantageously a paper 
present sensor at the entry of the print device. 
The feed means of the printer may be controlled by a microprocessor 
programmed to instruct a paper loading cycle comprising the following 
stages: 
opening of the lid and insertion of the paper roll into the magazine, 
insertion of the free end of the paper in the guide means by simple manual 
rotation of the paper roll until it is engaged with the feed means and is 
sensed by the paper present sensor, 
a first actuation of the feed means initiated by said detection to feed a 
sufficient length of paper for its free end to emerge visibly into the 
magazine, 
closing of the lid which by operating the microswitch reverses the feed 
means initially to retract the paper and subsequently feeds the paper 
again to a start of printing position with its end inserted in the slot. 
It is clear that the loading method has the advantage of requiring only 
extremely simple manual operations demanding the attention of the operator 
for only very short time periods. 
Furthermore, before closing the cover the operator can check that the paper 
is correctly inserted and that there is no jamming of the paper. 
The duplicated retraction/advance displacement then eliminates any possible 
onset of jamming and ensures that the paper follows the correct path in 
the printer. 
Another important advantage of this printer is that it does not require the 
end of the paper roll to be cut cleanly at right angles to enable paper 
loading. The paper roll end can be cut or even torn in any way. 
One embodiment of the invention is described hereinafter by way of 
non-limiting example only with reference to the appended drawings.

DETAILED DESCRIPTION OF THE INVENTION 
In this example the printer is mounted inside a substantially 
parallelepiped-shape casing 1. It is designed to be flush-mounted in a 
housing provided for this purpose in a panel 2 in the cockpit of an 
aircraft so that only the front panel 3 of the printer is visible and 
accessible to the pilot. 
The front panel 3 comprises on one side a printer control panel 4 carrying 
the various control and display devices and on the other side an orifice 5 
providing access to a paper magazine 6. 
The orifice 5 can be covered by a lid 7 hinged to the control panel 4 and 
incorporating a paper slot 8. 
The orifice 5 is naturally large enough to admit a paper roll 9 fitted with 
its support journals 10, 11, like that shown in FIG. 6, for example. 
The paper magazine 6 has a rectangular shape in horizontal cross-section 
substantially the same size as the orifice 5 constituting its upper side. 
It has two substantially vertical parallel longitudinal sides 12, 13, two 
transverse sides 14 and a curved bottom 15 whose concave side faces 
towards the interior of the magazine 6. 
The two transverse sides 14 of the magazine 6 comprise respective 
substantially coaxial half-bearings 16, 17 open upwardly and adapted to 
receive the support journals 10, 11 of the paper roll 9. 
Each of the two half-bearings 16, 17 is extended upwardly by diverging ribs 
18, 19 which guide the support journals 10, 11 into the half-bearings when 
loading paper (FIG. 6). 
To ensure that paper can feed from the roll 9 inside the magazine 6 in one 
direction only, the two support journals 10, 11 and the respective two 
half-bearings 16, 17 have different diameters. 
Parallel to the bottom 15 is a curved deflector 21 hinged to the 
longitudinal side 13 of the magazine 6 and spring-loaded by a spring 22 so 
that its edge 23 (that opposite the hinge) is applied at all times to a 
generatrix of the paper roll 9, irrespective of the diameter of the paper 
roll 9. 
With the bottom 15, the deflector 21 delimits an intermediate space 24 into 
which the paper is guided towards a paper feed device associated with a 
print device. 
In this example the feed device is a conventional type capstan roller 25 
driven by a stepper motor-gearbox 26 through gears. The print device 
incorporates a print head 28 movable along a generatrix of the capstan 
roller 25. 
A paper present sensor 29 is provided at the entry to the combination of 
the capstan roller 25 and the print head 28. 
At the exit from this combination the paper is guided between the mobile 
and fixed blades 30, 31 of a cutter towards an outlet slot 8 in the lid 7. 
An end of travel switch 36 senses the closed position of the lid 7. 
The electronic circuits controlling the printer are carried by printed 
circuit boards disposed in the space between the bottom of the magazine 
and the bottom of the casing. In this example, these circuits comprise a 
central processor unit board 41, an extension board 40 and a power supply 
board 42 associated with a filter capacitor 43. 
The process of loading the printer previously described comprises the 
following phases shown in FIGS. 2 through 5: 
In a first phase, the operator opens the lid 7 and inserts a paper roll 9 
into the magazine 6 so that the support journals 10, 11 engage in the 
respective half-bearings 16, 17. In this position the free edge 23 of the 
deflector 21 bears on a generatrix of the paper roll 9. 
On completing this operation, the operator rotates the paper roll 9 in the 
direction of the arrow F1 so that the free end 44 of the paper is inserted 
into and guided by the intermediate space 24 between the deflector 21 and 
the bottom 15 (FIG. 2). 
The operator continues this action until the end 44 of the paper is 
inserted between the capstan roller 25 and the print head 28. 
In this position the sensor 29 senses that the paper is present and causes 
the motor 26 to turn in the paper feed direction. 
The capstan roller 25 feeds the paper until it reaches a position visible 
in the magazine 6 (FIG. 4). The motor 26 is stopped and the lid 7 is 
closed. 
The fully closed lid 7 operates the switch 36 which commands a cycle of 
operation of the stepper motor 26 comprising: 
a first phase in which the motor 26 runs in the reverse direction until the 
free edge of the paper is exactly at the exit from the capstan roller 25, 
a second phase in which the motor 26 runs in the forward direction to move 
the paper to a start of printing position with its free edge 44 extending 
through the outlet slot 8. 
The printer is then ready to be used. 
The control panel 4 may advantageously comprise, in addition to the 
conventional on/off switch, cutter operating switch, etc, a control 
initiating a jam clearing process. 
When operated, this control could initiate a forward/reverse sequence of 
operation of the motor 26 until the jam is cleared.