Form printer

A form printer comprises: PA1 (a) a feed plate adjacent which a form is fed in a longitudinal feed direction; PA1 (b) a print head for printing the form; PA1 (c) a first drive roller or rollers at one longitudinal side of the print head, and a second drive roller or rollers at the opposite longitudinal side of the print head, the drive rollers adapted to move the form longitudinally; PA1 (d) a drive to drive the rollers in one mode to feed the form longitudinally forwardly, and then longitudinally reversely, to enable the print head to print on relatively widely spaced zones of the form.

BACKGROUND OF THE INVENTION 
This invention relates generally to form printing, and more particularly 
concerns the provision of a printer characterized as enabling printing of 
a standard credit card sales draft, as well as other forms, employing a 
dot matrix print head. 
Certain disadvantages and problems with current commercial printers are 
listed as follows: 
(1) Current printers are limited to a 40 alphanumeric character print line 
which is normally 3.3 to 3.6 inches long; 
(2) Current printers have feed rollers positioned behind the print platen 
or head, and do not allow for convenient entry and feeding of relatively 
small forms; 
(3) Current printers are constructed with a form entry slot or opening at 
the left side of the printer (relative to a user addressing the machine 
from the front), which does not allow for printing on the left extent of a 
form which more than 3.3 inches wide; 
(4) Conventional line spacing is accomplished by means of a ratchet feed 
mechanism which does not permit complete flexibility of printing of 
relatively large characters (i.e. taller than the seven dot matrix head). 
In addition, prior printers do not provide the unusually advantageous 
features and combinations of structure, function and result embodied in 
the present invention. 
SUMMARY OF THE INVENTION 
It is a major object of the invention to provide a printer overcoming the 
above disadvantages and problems associated with conventional and prior 
printers. Basically, the invention is embodied in a form printer which 
includes, in combination: 
(a) a feed plate adjacent which a form is fed in a longitudinal feed 
direction, 
(b) a print head for printing the form on the plate, 
(c) first drive roller means at one longitudinal side of the print head, 
and second drive roller means at the opposite longitudinal side of the 
print head, said drive rollers adapted to move the form longitudinally, 
(d) drive means to drive said rollers in one mode to feed the form 
longitudinally forwardly and then longitudinally reversely to enable the 
print head to print on relatively widely spaced zones of the form. 
As will be seen the first drive roller means typically comprises laterally 
spaced apart rollers, and the second drive roller means also comprises 
laterally spaced apart rollers. In addition, first pinch roller means may 
be located to urge the form against the first drive roller means, and 
second pinch roller means located to urge the form against the second 
drive roller means. Actuator means are also provided to selectively urge 
the first and second pinch roller means relatively toward the first and 
second drive roller means, respectively. 
It is another object of the invention to provide for the control of the 
drive of the first and second drive rollers. To this end, a first sensor 
is positioned to sense the edge of a form that has passed longitudinally 
forwardly between the first drive roller means and first pinch roller 
means, and operatively connected with the actuator means to cause the 
actuator means to urge the first pinch roller means toward the first drive 
roller means to pinch the form therebetween, whereby the first drive 
roller means then drive the form longitudinally forwardly. Also, a second 
sensor is positioned to sense the edge of a form that has passed 
longitudinally forwardly between the second drive roller means and second 
pinch roller means, and operatively connected with the actuator means to 
cause the actuator means to urge the second pinch roller means toward the 
second drive roller means to pinch the form therebetween, whereby the 
second drive roller means then drives the form longitudinally forwardly. 
In addition, the drive means to drive the rollers typically comprises a 
stepper motor operable to alternatively travel the form forwardly or 
rearwardly during travel intervals and to arrest form advancement during 
arrest intervals, to enable printing on the form by the print head during 
the arrest intervals. 
The printer typically includes a dot matrix printer characterized in that 
the dots printed on the form to delineate an alphanumeric character are 
successively located to merge with one another and form character lines. 
In addition, the printer and apparatus may be further characterized in 
that the character forming dots form first portions of a line of 
characters during an arrest interval in forward travel mode and the dots 
form other portions of of said line of characters during an arrest 
interval in reverse travel mode. 
As a result, the following unobvious advantages or results are provided: 
(a) The invention permits the provision of a longer print line (as for 
example 4.25 inches) and more (such as 51-55) characters per line, as 
compared with a standard printer; 
(b) the dual drive roller feature of the invention allows forms to be fed 
into the printer over front rollers prior to feeding under the print head, 
so that forms can be printed over substantially all of the form area; 
(c) the forms can be positioned either to the left or to the right of the 
print line permitting printing on the left or right side of the form; 
(d) use of a stepper motor for the feed roller drive enables use of 
software control permitting complete flexibility of line spacing, i.e. 
larger or smaller line widths, in the direction of form feeding, 
(e) a highly efficient, compact, versatile and flexible printer 
construction is provided, as will appear. 
These and other objects and advantages of the invention, as well as the 
details of an illustrative embodiment, will be more fully understood from 
the following specification and drawings, in which:

DETAILED DESCRIPTION 
The form shown at 10 in FIG. 1 (which may comprise a standard credit card 
sales draft) has longitudinally spaced, laterally extending printed lines 
of printed alphanumeric characters. See longitudinal directional arrows 
11, and lateral directional arrows 12. By way of illustration, the number 
"7" in the scan line 13 of characters may be formed by printed dots which 
merge together, as seen in FIG. 6. The dots appear at 60a. 
Extending the description to FIGS. 2-4, the form 10 is shown as being fed 
forwardly, in the longitudinal direction of arrow 11a by or in a form 
printer apparatus 15. The latter includes a feed plate 16 on which the 
form is placed downwardly, the plate extending horizontally. To this end, 
the edge 10a of the form may be placed in engagement with longitudinally 
forwardly extending guide flange 16a shown in FIG. 4, that flange carried 
by the plate. The plate is in turn carried by frame structure 17 which 
includes a lower portion 17a an upper portion 17b, and structure 17d 
interconnecting the portions 17c and 17b. Upright structure 17c is 
confined to a forward zone beyond drive roller means (to be described), 
whereby lateral movement of the form on the feed plate, and over the drive 
roller means is essentially unobstructed. (The guide flange 16 may be 
re-positioned or removed, to allow such form lateral movement, whereby all 
surface areas of the form may be printed, if desired. Thus, the frame has 
a "C" shaped construction, as is clear from FIG. 2. 
A print head 18 is carried by the printer frame, and in particular by upper 
portion 17b thereof, so as to print on the form located on the feed plate. 
Note the lower print end 18a of the head, directly over the form extent 
10b in FIG. 2. A print platen may be located at or associated with that 
portion of the plate indicated at 16b, beneath the print head. The print 
head is supported to traverse laterally over the form, to print thereon as 
during "dwell" intervals, defined as intervals of non-advancement or 
nonretraction of the form. Such support may be provided as by a follower 
sleeve 19 carried on a lateral feed screw 20 supported by the vertical end 
walls 17d of the frame structure portion 17b. The screw 20 is rotatably 
driven as by motor 21 and transmission 22 (including gears 22a-22d). 
Helical external cam shoulders 23 on the screw mesh with corresponding 
interior shoulders (not shown) on the follower, to travel the follower 
back and forth along the screw, during operation of the print head. See 
also lateral guide bars 24 and 25 between which the print head structure 
travels. The print head may be dot matrix impact type, one representative 
model M-400 produced by ETN Printer Products of Riverton, WY. Another is 
model 542 produced by Epson Company of America. 
In accordance with the invention, first drive roller means 27 (as for 
example laterally spaced drive rollers 27a and 27b on common shaft 28) is 
located at one longitudinal side of the print head; and second drive 
roller means 29 (as for example laterally spaced drive rollers 29a and 29b 
on common shaft 30) is located at the longitudinally opposite side of the 
print head, the drive rollers adapted to displace or move the form 10 
longitudinally. The shaft axes appear at 28a and 30a, in FIG. 4, and they 
extend in parallel relation, laterally, and are longitudinally spaced 
apart. The rollers project upwardly in openings 31 in the feed plate 16, 
as shown, to engage the underside of the form 10. 
Also provided is drive means to drive the rollers 27 and 29 in one mode (as 
for example counterclockwise in FIG. 2) to feed the form 10 longitudinally 
forwardly under the print head (to enable printing of all or widely spaced 
areas of the forms) and then longitudinally reversely, for form retrieval, 
and/or additional printing on the form. The drive means may advantageously 
comprise a stepper motor, shown at 130, operable to alternatively drive 
the form forwardly and reversely during travel intervals, and to arrest 
form advancement (or retraction) during arrest intervals to enable 
printing on the form by the print head and during the arrest intervals. 
The motor is typically connected with both drive rollers, as for example 
by the gearing at 32, and including gears 32a and 32b and 32c. Operation 
of the motor (ON, OFF, FORWARD, and REVERSE) is controlled as via lead 33 
by controller 34, shown in FIG. 5. 
Also provided is first pinch roller means (as for example pinch rollers 36 
on shaft 37) located directly above the first drive rollers 27a and 27b to 
urge the form against the latter; and second pinch roller means (as for 
example pinch rollers 38 on shaft 39) located directly above the second 
drive rollers (29a and 29b) to urge the form against those second drive 
rollers and pinch the form therebetween, whereby one or the other of the 
drive rollers urges the form longitudinally forwardly and longitudinally 
reversely (depending upon the direction of rotation of the drive rollers). 
For this purpose, the pinch rollers may be carried by a yoke 40 which is 
rocked about lateral axis 41a (see lateral shaft 41 in FIGS. 2 and 3) as 
by a solenoid 42. The latter has a plunger and link 42a connected with arm 
43 which is integral with the yoke arms 40b and 40c. When the solenoid 42 
is activated (as by controller 34 and lead 44) in one direction, the yoke 
is rocked clockwise in FIG. 2, to cause pinch rollers 36 to urge the form 
10 against the rollers 27a and 27b, whereby the form is driven by such 
rollers; and when the solenoid is activated in the opposite direction, the 
yoke 40 is rocked counterclockwise in FIG. 2, to cause pinch rollers 38 to 
urge the form 1 against the rollers 29a and 29b, whereby the form is 
driven by those rollers. Rollers 38 are retracted relative to rollers 29a 
and 29b when rollers 36 are urged toward rollers 29a and 29b, and vice 
versa, leaving the form gripped by rollers 27a and 27b, or by rollers 29a 
and 29b, to ensure precision drive and form location relative to the print 
head. (In FIG. 2 both rollers 38 and 36 are shown in engagement with 
rollers 29a and 29b for simplification of the drawing. 
A first sensor 50 is positioned to sense the passage of form forward edge 
10f past the sensor (upon manual insertion of the form between rollers 27 
and 36). That sensor is connected at 51 with the controller 34 and the 
latter with the actuator 42, to cause rocking of the yoke 40 and positive 
forward driving of the form by rollers 27a and 27b. When form leading edge 
10f advances over rollers 29a it is sensed by a second sensor 53 at gap 
32. That sensor is connected at 54 with the controller which causes 
rocking of the yoke 40 in the opposite direction to initiate further 
positive forward driving of the form to bring its near rear edge 10g under 
or nearly under the print head. In this way, the entirety (or near 
entirety) of the form is brought under the print head for printing 
thereon. 
When the leading edge of the form reaches a sensor 60 (at which time rear 
edge 10g is near the print head as described), the sensor 60, connected at 
61 with the controller, causes the controller to reverse the rotation of 
the drive motor 30, which then reversely drives the rollers 29a, 29b, 27a 
and 27b, to reversely drive the form from the printer. 
The controller 34 may incorporate suitable fixed software 90 (or hardware) 
to command the print head motor 21, stepper motor 30, solenoid 42, in 
response to sensing of the form edges as by sensors 51, 53 and 60; and 
suitable variable software 91 to command the variable data printing 
accomplished by the print head 18. In regard to the latter, the printer 
and the variable software may be characterized in that character forming 
dots form a first portion of a character (or line of characters) during an 
arrest interval (or intervals) in travel mode of the printer in one 
transverse direction; and the dots form other portions of the line of 
characters during an arrest interval (or intervals in travel mode of the 
printer in the opposite transverse direction. See in this regard FIG. 6a 
wherein printed dots indicated at 60a are formed during an arrest interval 
of the form 10 while the print head 18 is traveled to the right (arrow 
70a) by feed screw 20 (see FIG. 3) and on guide bars 24 and 25; and 
printed dots 60b are formed during a subsequent arrest interval of the 
form 10 in FIG. 6b while the head 18 is traveled to the left (arrow 70b) 
by screws 20. Dots 60a are spaced apart, but dots 60b merge with dots 60a 
to form a solid character, due to the indexing of the form 10 in the 
direction 11a. This is shown by the distance "d" of the printer from the 
form edge 10c in FIG. 6a, and the distance d+.DELTA.d of the printer from 
the form edge 10c in FIG. 6b, where .DELTA.d is the indexing distance. The 
controller 34 controls the drive 21 for the printer 18 as shown in FIG. 5. 
FIG. 6c shows dots 60a and 60b formed on a form as described above. Also, 
dots 60c are formed during a later rightward pass of the print head, and 
intermediate dots 60d are formed during a leftward pass of the print head 
(corresponding to formation of dots 60b). Thus, all the dots 60a-60d form 
one character, in response to two complete back and forth passes of the 
print head. 
FIG. 7 schematically shows the two pinch rollers 36 and 38 operated by 
solenoids 136 and 138, as via levers 136a and 138a, suitably pivoted as at 
136b and 138b. A print ribbon 140 is shown between the print head 18 and 
the form 10. 
The stepper motor and controller 34 monitor the exact location of the form 
10 relative to the print head to enable such exact printing, as 
facilitated by the precision engagement and drive of the form under the 
control of one or the other of the drive rollers, at all times. 
In FIG. 2, a print ribbon (not shown) typically passes between the bottom 
18a of the print head and the form. 
Variations of the invention include the alternate drive of the print head 
18 as by a belt drive, instead of the drive screw 20. Also, the frame can 
be constructed without closed ends. Other means for alternately driving 
the pinch rollers can also be provided; further, in view of the locating 
of the pinch rollers at opposite sides of the print head lower end 18a, 
and provision for oppositely rotating the pinch rollers, a form to be 
printed can be inserted or fed at either end of the feed plate, i.e. front 
or back. Finally, the device is accommoated to printing documents that are 
OCR (optical code readable) scannable--i.e. a carbon copy is scannable. 
FIGS. 8 and 9 are rear and front perspectives of a typical housing 200 for 
the apparatus of FIGS. 1-3. Rear and front entrances and exits (depending 
on document direction of feed) appear at 201 and 202.