Note: Descriptions are shown in the official language in which they were submitted.
~L~81~
A tag reader
Background of the invention
This invention relates to a tag reader tor coded
price tags~ Such tags were introduced about twentyfive
years ago and are provided with machine readable codes,
normally in the form of a hole code. Examples of such
tags are the so-called Kimball tags. Such tags are fixed
to merchandise in many retail stores, and when an oblject
is sold, the sales-person takes away and collec~s the tag
or a detachable piece thereof, and those liberated t.ags
axe then treated by machine in order to keep contxol over
sales and stockO The actual processing o the collected
tags .ts made as batch processiny, and it is normal for
such processinc3 to be made at the central headquarters of
a mult1ple chain of sto.res.
With present actual practice, this reading is made
on big and fast machines, and such systems are popul.ar
and widely used.
At the actual sales moment, the tag serves also as
a price tag, there being printed thereon a price in read
able form Howeverl at that moment, the handling of the
t~gs is often felt as a nuisance by the salesperson, as
it has to be put on a spear or the like~ to be colle!cted
in an oxderly manner w:Lth other tags, to be sent lat.er to
headquarters Thus, the tags can mean extra work at busy
~&"
times when the salesperson rightly thinks that the
important thing is to serve the clients as quickly as
possible.
There are known various additional devices for the
Kimball system. In one instance, an ordinary cash register
has been provided with a collector for tags where for each
sale of an object, the corresponding tag is entered and
provided with extra hole codes for salesperson, actually
paid price etc. However, the tags are not read and not
used for automatic entering of prices into a cash register.
There are also known various readers for Kim~all
type tags. An example thereof is the so-called High-Speed
Kimball Reader, wherein a stack of tags i.s entered and
the tags are brought one by one in front of a row of
photodetectors, which receive light through code holes
where such are punched in the tags. In order to feed the
tags, they are provided with two round feed holes, where
radial pins of a pinwheel enter and bring the tags along
a path around a circumferential portion of the rotating
pinwheel, Although this machine is very rapid~ t is only
suitable for batch processing,
Object.s of the invention
._ .
It is an object of the present invention to cbtain
an improved registering system builcling upon the wellknown
Kimball tag principle as described above, It is another
object to eliminate the nuisance value of the collection
of tags particularly at xush hours in a crowded stc,re.
A further object is to eliminate as much as possible the
work of entering prices on a keyboarcl when articles
provided with tags are sold,
A further object is to obtain a system where hole
code marked tags may be used compatibly with printed code
marked tags and also to use only printed codes which may
be providecl locally by means of simple pxinters instead
of being clelivered from a central, It is also an object
to obtain a machine of the same type which can read tags
of other kinds, e~g. the code type called IJPC in the USA
and EAN in Europe, and which is a bar code. According to
a special aspect of 1he invention, it is also an object
to make changes in price easy in a shop where the
merchandise is marked with tags, e.g. when there is
a sale or promotional event.
Advanta~es of the invention
Fxom the salespersonls view, the inventive tag
reader functions in the fc>llo~iny way. When an article
is to be sold to a customerl, its tag or a detachable
piece thereof is removed and stuck into a slot in the
reader. Although there is normally a visible price
indication on the tag, the salesperson does not neecl to
read it. When the tag is stuck in, the reader reads
a price code from the tag and a price signal is carried
over to the cash register and registered. If severa:L
articles are to be sold to the same customer, their tags
are ~ed in one after another, and when all the tags ~or
a partic~lar purchase have been fed in, the salesperson
presses a buttom Eor the sum total, ancl the cash register
makes the sum in a normal way and delivers a pay slip.
Sometimes, a tag may be unreadable or faulty, and
the reader will then deliver that tag in a special output
collector, giving off a signal which may be an audihle
signal or a visible signal or ~oth. The salesperson may
then try to enter the same tag again. (A tag inserted
upside down will be pushed back i~nediately.) If it is
not ~ead then, the salesperson may read the printed
in~ormation on the tag and enter the price in the cash
re~ister manually, by means of its normal keyboarclu This
may also be necessary for articles where the price has
been reduced so that t:he price in the tag code is no
longer valid. Such tags which are given a special treat~
ment will normally be~ stored sepaxately~ whereas the
tag~ norma:Lly read are collec~ed :inside the reader~
rV ~
From the point of view of the direction of tlie
shop, the invention presents the following advantages.
The reader may deliver the information of the tags
d.irectly at t-he sales moment to a data register, e:ither
on~line or through a-suitable medium. It is possib:le to
provide e.g~ an ordinary magnetic tape cassette fo:r
registering the data of the tags. This medium can then
suitably register all the other data and not only the
price, so that there may be kept track over the stock
and to rapidLy split up turnover e.g. in respect of
product~ sizes of garments etc~ A distribu-ted system is
thus obtained instead of those centralized systems which
have previously been used for the same purpose
In the presently preferred embodiment, the tag
reader is able to read normal tags of the so-called
Kimball type and also alternatively tags where the code
is not a hole code but a printed code which may be
similar to the Kimhall type code. In order to obtain
a compati~le system, the alternative tags should have
gui.de holes which are similar to those of the old kind
of tags and which are used for feeding purposes. The
hole codes and the printed codes can then be read in
a simllar manner, and if the new kind oE tags are
provided with a special signal mark, it is possible to
let such a mark control the manner of reading such that
the salesperson need not bother to readjust the reader
but can enter code tags of both kinds in any order at
will. According to a special feature, the tag reader
can read both holes and ink maxks by means of the same
equipment and entirely indiscriminately.
Normal tags of the kind previously known are
usually manufactured on special machines which a.re qui~e
expensive~ so that i.t is necessary to have a centralized
manu~acture axranged With my system using alternative
-tags which are printed, it is possible to use very
simple printing machines and e.g. let the prin~i.ng be
governed by pre-~abrlcated guide holes in ~ag blanks.
~ the invention
_
The objects and advantages of the invention are
ohtained by a new type of ta~ reader which cooperates
with ~ cash register Although at present, the tag reader
is enYisaged as a separate item to be coupled to a cash
register of the modern electronic type, which can accept
electrical codes alternative to codes entered on its
keyboard~ such a tag reader may also be built inlo a cash
register or other machine with a similar function. It is
therefore not intended to limit the invention to the case
of a separate tag reader, although this is the pre-,ently
preEerxed embodiment.
According to the invention, there is thus provi~ed
a tag ~eader having an entry slot for entering tays one
by one manuall~-/ one at a time in succession, a sensor
~or sensing the presence of a manually entered tag, means
for performing an optical reading operation on machine-
readable codes on a tag entered and sensed, parity
checking logics providing for error readings on sa:id tag,
means Eor deviating a tag where a parity error is sensed,
means ~or ejecting a deviated tag, means or recording
xead code information on a tag free of error readings,
means for transmitting said recorded code to a cash
register ~o~ entering a price therein and means fo:r
~5 collecting recorded tags.
According to another aspect of the invention, there
are provided means or manually entering a -tag into
a Eirst path ending against projections on a pinwheel
havlng two pins arranged behind the projections for
manually pushing a tag against the projections and there-
by activating switch means for starting rotation o:E said
pinwheel~ said two pins thereoE being arranged to grip
two holes in said tag Eor bringing it along a second,
arcuate path, optical reading means adjacent said arcuate
path ~or sensing code markings thereon, reject means or
emitting a re~ect signal when a signal from said optical
,
v~
readiny means is erroneous, deviating means ~ctivaled
by said reject signal for ejecting a bad tag, and
collecting means for assembling correctly read tags"
According to a preferred embodiment, the tag reader
is pro~ided with double reading mode facili~ies~ so that
it can read an ordinary hole~code tag or a tag provided
with ink markings instead of code holes. Both kinds of
tags must be provided with similar feed holes, as they
are mechanically treated in the same way. However, the
optical reading must be made differently, althouyh it is
envisaged to use the same code positions. It is possible
to use one and the same set of optical sensors in both
cases, for example by sensing the lowered transmission
of light at a position provided wit~. a point of pr:Lnted
ink, whereas a hole is sensed by more light being 1:rans-
mitted through the tag. It is also possible to arrange
two sets of sensors, one for sensing transmitted light
from ~ lamp on the opposite side of the tag path, 1he
other for sensing reflected light from a lamp on the
same side of the tag path. Normally tnen~ the firs~
sensor set senses pulses of light, whereas the second
set senses "black" pulses against the reflecti.vity of
imm~c~late paper.
It is neces.sary to sense which kind of tag i'3 being
re~d. It is possible to do this by sensing the absence of
a hole code by one sensor set and to activa~e the other
sensor set in such absence, and it is then advantageous
to mount the other sensor set downstream from the hole-
sensing sensor set. However, it is also possible to
arrange a punching or an ink-marking in a pxedetermined
spot on the tag for indicating that a tag is of one of
the kinds, and in the reader a spec.ial sensor for signal-
liny its existence fc,r selectiny the appropriate reading
mode.
~t is ~lso posc.ible to arrange a reader for :reading
mexely printed codes in tags, thus modifying the s'ystem
~ 3~
by abolishing entirely the use of code holes, keep:Lng
only those holes in tags which serve purposes of location
and feeding. Codes in tagC may then ~e printed in
~ printing machi.ne, using the edges of the tags as
indicia for assuring that code markings fall on the right
spots and not beside, thus assuring readability.
The invention may also be seen in the aspect of
providin~ a system for accounting and reglstering pur-
chases at a polnt of sale, comprising a cash regis~er of
electronic type which is capable of admitting electrical
price code signals, and wherein there is added a tag
reader, so that tags :may be read and their price informa-
tion automatically entered in the cash register in lieu
o~ price information :manually entered by means of the
cash register's keyboard. The tags are taken from sold
merchandise and entered manually one at a time, wh:ich
operation serves the same purpose as the salesperson's
entering of the price on the keyboard as previously made.
It is possible to read other information as well f:rom
the tags for entering into a memory, store, computer or
the like, exhausting all the information on the tags for
treatment for all kinds of accountance purposesO
By cash register is meant a machine such as :is used
for adding sums of purchase, and from the standpoint of
the imvention, it is immaterial i.f it is provided with
a money till or not~ whether it is a uni.t for registering
purchases in a cxedi-t card system or if the registering
of purchases is made in some other way. The usefulness
of the inven-tion would not be impaired by its use with
such re~isters, and the use of the term cash register is
not implied to limit the invention to such cases where
actual money cash changes hands.
Bxief description o~ dra~
_ .
Fig. 1 shows an inventive tag reader soupled to
3S ~ cash register
Fig. 2 shows a simplified exploded view of a tag
reader.
Fig. 3 is a schematic drawing explaining the
electrical functions of the tag reader of Fig. ~.
Fig. 4 is an exemplary logic circuit for treating
signals from the circuits of Fig. 2.
Fig. 5 shows a circuit for adjusting illumincltion
of a tag depending on its type.
Fig. 6 shows wavefor~s encountered in tag reading
operations.
Fig. 7 shows a circuit ~or sensing a phototransistor.
Fig. 8 is a schematic diagram showing sensor posi-
tion for hole and edge sensing on a tag.
Fig. 9 is a schematic figure showiny hole and edge
sensing related to a pinwheel.
Fig. 10 shows a logic diagram over a motor control
circuit.
Fig. 11 shows waveforms of the circuit of Fig. 10.
D _ cription of a preferred embodiment
In Fig. 1 is shown a tag reader 1 coupled to a cash
register 2 of an electronic type (in this case a CASIO
model ~-26ER~. A tag 3 of the Kimhall type is entered by
hand ln an entry slot: 4 and pressed slightly in by hand.
The reader will then start r and the tag 3 vanishes into
the reader 1. As can be seen, the reader 1 is coupled to
the cash register~ and if the tag 3 is successfully read,
the cash register wi]l enter a price in its memory, show
it on the window 9 and print it on a sales slip 7. When
a number of tags have been read corresponding to a pur-
chase, the vendor presses a sum total button on the key-
board 6, and the sum is calculated, whown in window 9
and printed on slip l. The tags 1 read are collected in
a box inside the reader, which may have the form of
drawer 8. If there i'3 an erroneous tag, it will instead
be thrown out ~n e~it 5, so that the vendor can enter
the price not read (printed on the tag) by means of
key~oard 6.
In Fig. 2, there is shown an exploded view of a tag
reader. It may be seen that under the tag entry 4, working
as a slot, there is a kind of drum or pinwheel lO.
Guides 12 and 13 are mounted adjacent the circumference
o~ the wheel lO, the interspace forming a prolongalion of
the track defined by the tag entry 4. A tag entered will
be brought against projections 16 on ~he drum, and means
to be described below indicate electronically that a tag
has been entered. This starts motor ll, which star1s to
rotate in the direction indicated~ A pair of projections
or pins 17 then grip corresponding holes in the tag and
bring ~t along. ~ lamp LS inside the drum sends ou~
light through an opening in the drum, and this light is
sensed through the tag by means of a set of light sensors
lc., comprised in a logic circuit for sensing codes on
the tag brought in front of the sensors.
The sensors comprise optical fibers l9 coupled to
light-sensitive elements 20, prefexentially phototran-
sistors. Alth.ouc3h this is not shown~ there should be,
for a Kimball tag, ten such sensors directed to sense
ten different positions for holes or, according to
a special embodiment, printed markings which can also
2S be sensed
There is a feature in the logic system to be de-
scribed which determi.nes whether information read is
acceptable. An accept.ecl tag will follow a first path
down lnto dr~wer ~'. There is also a bifurcator 14 which
may be activated to send a misread tag into another path
ending in exit 5. This biE~rcator or switch (as under-
stood in railw~y ter%ls) may be activated by motor or
relay 15 moving ~lag or guide 14. Motor or relay 14 is
controlled electrical.ly by means of logics to be expl~ined.
In Fi.c3. 3, there is a schematic drawing showing
more in detail how a tag is read For simplicity, the
curved path.i:s exchanged for a straight path.
A tag of one of the envisaged types is provided
with holes as shown. There are feed holes 21, 22 and 23,
of which holes 21 and 22 are used as explained in con-
nection with Fig. 2,
- 5 There are further 10 x 12 hole positions function-
ing as a code pattern, there being twelve rows correspond-
iny to 2 x 5 positions which ten positions are read
simultaneously ~y the row 18 of sensors previously
mentioned. It is noted that the same positions may be
provided with ink dots instead of holes and tha~ the
reader may read such codes alternatively~ (It shou:Ld be
emphasized that, although this exemplifies a very common
type of coded tag, the invention is not limited to
a particular card ~ut may be used with any kind of card-
like markers provided with code markings in rows and
columns,~
First, the start operation shall be explained. When
a tag is inserted, its edge will break the liyht path
between a light source and a phototransis-tor, which pair
is schematically designed as 24. Further, there is
arranged a set of at least two photosensors 25 and 26 at
feed hole 21, sensiny light through the hole 21 at the
start position or the tag. A circuit 27 decides when
sensor 24 senses a tag and sensors 2S and 26 simultane-
ously sense light through hole 21. The constructional
features of cir~uit 27 do not have to be described, being
well in reach for the electronic man of the art. When
this combination is sensed, motor 1~ is s-tarted as of
Fig. 2. It is noted t:hat this gives a control so that
if the opposite edge of tag 3 is presented, there wil.l
be found no hole 21, and the apparatus will not start.
(~f tay is presented upside down~ there will not be any
hole at the position of hole 21, and there is no start
either.)
The sensirlg of the hole 21 toyether with the
sensinc~ of the edge ~y sensor 24 is thus an important
featu~e of the invention. According to a preferred
embodiment, the motor 11 (Fiy. 2) is made to start in
the reverse direction if hole 21 is not detected, thus
rejecting the tag ~y pushing it towards the fingers of
the person who introduces it.
In a preferred embodiment~ this sensin~ of hole 21
and edge of tag is made in a slightly more complicated
way, where two optical hole sensors Hl and H2 take the
place o~ sensor 24 in Fig. 3, which are positioned in
a row in order to sense successively the hole, with two
edge sensors Kl and X2, also in a row. This is schematic-
ally shown in Fig. 8. In this embodiment, the drum is
also pro~ided at one side with a hole P, and at the
"home" position, this hole P falls in front of an optical
sensor S, as shown in Fig. ~ At an adjacent position SB,
thexe is another optical sensor, which senses when the
drum 10 has mo~ed backwards a certain amountO
Said optical sensors Hl, H2~ Kl, K2, S and SB are
part of a ~otor dri~e system shown in Fig. 9 for driving
the motor 11. Since anyone skilled in the electronics art
can understand the fullction of this circuit with less
than a complete descr:iption of all the gates, it is
su$$icienk to explain that the gates indicated A are OR
gates (e.g. 4075) J the gates indicated l~ are NOR gates
(e,g. 4001~ and the gcltes indicated C are AND gates
(e.g. 4073~. Vl - V5 are "one bit memories"~ Vl being
a hole memory, V2 "tag OK memory", V3 "Forward" and V4
"Backward". OX~ and OKB are optocouplers for ordering
motor 11 to turn ~oxward and backward, respectively.
The ~unctioning of this ~em will now be described
step by step with particular reference to Fig. 9 and 11,
which latter shows a diagram o$ waveforms in the circuit
o~ E'ig. 1~.
1. A tag is brought into the slot.
If corre_ If wronq
2. Edge sensor Kl senses
edge and goes low. Same
Zeroing of memories Vl,
V2 and V4 is removed.
3. Hole sensors Hl and H2
go low, with Hl first. Nothing
This sets Vl, the hole
memory.
4. Edge sensor K2 goes low, K2 goes low and V4 for
and V2, "tag OK", is set, backward movement is set,
due to Vl being set, If since Vl is not set.
S, "home", is or becomes
high, and PF ~rom central
logic gives clearance
signal by being low,
V3 is set~
5. The tag is ,Eed by motor 11. The tag is brollght back
until hole P is brought to
position P' (Fig. 8~1 and
makes SB go high. This
zeroes V4, which sel:s V5,
the backward memor~,L
6. When ~ehind edye of tag Tag is taken out manually,
leaves Kl, Vl, V2 and V4 making Kl go high. ~s V5
are again brought to zeroO i5 high, V3 is set, and
drum 10 is turned forward
until S goes high again
and V3 is zeroed. When V3
was set, V5 was zeroed.
7. When hole P is brought
anew in position to make
S high, the feed is comp-
lete, ~nd ~3 is zeroed.
The reason for sensor K2 is to assure that the tag
is brought down far enough to assure tha-t it can be
yripped securely by pins 17 in holes 2:!,22.
It may be noted that in the embodiment of Fig. 9,
projections 16 of drum 10 are exchanged for a step 16',
and one pin 80 is provided for hole 23 (Flg. 3) of tag 3.
In Fig. 11 are shown some waveforms explaining the
circuit of Fig. 10u Hl and H2 are the signals from two
hole detectors placecl as apparent schematically from
Fig. 9; whereas Kl and K2 are edge sensing siynals as
apparent ~rom Fig. 8 and 9. When a tag is introduced, Hl
first goes high, as t:he tag blocks the light, and then H2
goes high for the same reason. Then, Hl detects the hole
and goes low again, whereafter H2 detects the hole. D is
~ delayed ~ersion of H2, by means of an RC circuit, and
which is sent to the D input of "hole memory" Vl~ The
"clock" input of this circuit receives the signal denoted
as Cl in Fig. 11. - It is noted that circuits V2-V5 have
thei~ D inputs positive and are there:core set by their
clock input going high
As shown in Fig. 10, the drive circuit for the motor
11 is activated by means o~ optor-couplers OK~ (forward
movementl and OKB (backward movement).
Sensors F~l-FT10 are coupled to a logic 28 having
~eatures which will be described with reference al~,o -to
~ig. 6.
Lo~ic 28 has one output 2'3 which ~ignalizes that
all photosensors 18 are receiving light. This is normally
the case e.g when no tag has reached reading position.
When motor 11 (Fig. 21 starts, the edge of tag 3 w:ill
re~ch the row of sensors 18, and they will all turn
"dark". The signal "all light" on output 29 will go low~
and logic operation will start. Reading phase will end
when tag has passed beyond sensors 18 and "all light"
on output 29 goes hlgh.
14
On output 30 of logic 28, there is sensed a signal
"all dark", which goes high when all the sensors 1~ sense
low light intensity. When a code hole comes before one of
the sensors, this signal goes low.
It ~ay be explained here that the Kimball type cocle
is constructecl such that a group of five hole positions
comprise a cipher position and that all numbers 0-9
correspond to a pair of holes ( ~23 = lo ). Thus~ any
correct cipher position will show exactly two holes~ At
Position 1, signal "all dark'l will thus go low as apparent
in Fig. 6. Then, all will go dark until Position 2 is
reached, etc.
E~ch of the ten signals from sensors 18 is coupled
to an entry on logic 28, and there are ten outputs on
logic 28~ indicated as Dl-D10. (Logic 28 thereby also
works as an interface to following circuits, which are
C-~OS.I Those outputs are individually high when a corre-
sponding hole code is present. They are all coupled to
parallel inputs on a shift register S/R FF.
As apparent from Fig. 3, SR-FF ("set-reset flip-
flop"l has ten parallel inputs, ten parallel outputs and
a reset input R. A pulse to reset input R will reset all
the flip-flops If one of the signals Dl-D10 is high, its
corresponding flip-flop will switch, making its correspon-
ding output high permanently, until the circuit is reset
by input R ln the pre~erred embodiment, this circuit
SR-FF is a C-MOS circuit known as 4043 (available from
several manu~acturexsl It is noted that this particular
"latch circu:it" does not use any s~robe input, which is
an advantageous featuxe as the positions on a tag may be
ill defined, so that a strobed latching would be difficult
to t.ime adequately in view of poor precision of location
and various defects encountered in tags.
The si~nal OUtplltS Dl-D10 from S/R FF are clocked
into inputs shown in Fig 4 by means of pulses "all dark".
When the first "all dark" comes~ meaning that the edge of
a -tag 3 has been inserted and obstructs all the sensors
18, the first strobing of the circuit in Fig. 3 will
transfer all outputs Dl-D10 as active, as the sensors
were previously all lit.
The "all dark" signal is led to a circuit PF which
creates a reset signal with a slight delay, which then
resets all the flip-flops in S/R FF. They thus start in
"dark" conditions. As soon as one or more of inputs Dl-D10
goes high, indicating hole codes, signal "all dark" on
head 30 will go low. We are then at Pos. 1 in Fig. 6.
A corresp~ndiny flip~lop will give a high output in
S/R FF ~t the end of Pos 1 in Fig. 1~ the "ali dark"
signal will go high again, as there are no holes in front
of sensors 18. The same "all dark" signal will clock in
the prevailing contents of S~R FF to the circuit of Fig.4,
and circuit PF will anew reset the flip-flops at R. This
is proceeded with row by row, until the tag ends and
signal "all light" goes high, as the opposite edge of
tag 3 has passed sensors 18.
As has now been explained, there are fed from S/R FF
in Fig. 3 a succession of parallel output signals consist-
ing of first ten alike parallel ones and then twelve
successive code sets, These are led into bus s~itches AI
and AII (Fig. 4), five into each and switched into switch
register.s 31 and 32 on a parallel bus input, and clocked
in by signal "all dar~". There are 1~ x 10 positions all
together in the switch registers~ and when all twelve bits
have heen entered into each individual input, the first
bit entered will have vanished. In case there is a defec-
tive readiny such that less than twelve parallel codes
have been entered, the first inputs will still remain in
the shift registers 31 and 32, and the utility o~ this
for error sensiny will be explained below.
~hen si~nal "~11 light" goes high again~ a data
t~e~t~ent phase starts undex control of logic 33~ Switches
~ ~nd ~II are set such that ou~puts from registers 31
and 32 are led in a circular path by buses 34 and 35.
The shift re~isters 31 and 32 are clocked by clock signals
from the logic 33, and the successive outputs are led to
an error detector 36. This error detector for each
parallel half corresponding to Dl-5 and D6-10 respectively
are controlled for the existence in each of exactly two
active outputs and three inactive outputs. In case there
are more or less, an error signal is generated, and the
reading is rejected. If no error is found, a new set of
twelve clock pulses is emitted, this time for reading-out
purposes.
The codes are thereby led to a decade coder which
trans~ers the Kimball codes into a suitable form for
a writer, cash register, a computer and~or some register
ing medium,
It is again noted that if there have been read less
than twelve rows of Kimball codes7 the first bits read in,
~11 active, will remain in the shift register and will be
detected as an erroneous code in error detector 36.
It is noted that it is preferred to let motor 11 of
Fig. 2 work in a step-wise way, e.g. by using a step motor,
and stop the motor 11 in a position where a tag has been
read hut remains between pinwheel 10 and guides 12 and 13.
It is then possible to hold a passed tag until the data
have been treated and no fault has been found. Only then
will the motor 11 ~e allowed to start again in order to
let the tag ~all into box 8'. In case the error detector
36 activates~ motor 15 is activated to swing the switch 14
so that the erroneously read tag goes to exit 5, for
m~king another attempt at reading or for manual handling.
In Fig. 4, there are shown terminals of logic 33
which are used for control signals. In the embodiment as
shown in Fig. 1, the cash register will take in prices
~igure by ~igure as an ordinary adding machine. When all
the ~gures of a price have been entered, logic 33 sends
~ sum signal to the ca5h register, which will then
36
automatica]ly make the operations previously de~cri~ed.
In other types of data collectors t other kinds of control
signals are used, for instance strobe signals, and there
may be an acknowledge signal indicating that a new figure
may be fed. The various modifications necessary for such
use are known in the art.
According to a preferred embodiment, the same code
reader may also be used for printed codes instead of hole
codes. This may be obtained by means of letting a photo-
transistor sensor sense light through the ticket at a rowposition where th~re are no holes or printed signs~ This
sensor is coupled to control the light source LS such that
it will set to a~out half maximum light output when light
attenuated by tag is sensed by the sensor. This may be
e.g. sensor 25 or 26 o Fig. 3, and a circuit therefor is
shown in Elig. 5. When a hole passes one of phototransistors
FT l-lO~ or there is no tag, those sensors will go low,
and if a printed spot is found in a "hole position", the
respecti~e phototransistor will go high. The outputs are
sensed by windo~ discrirninatoxs in logic 28, which give
out passi~e d~ta levels around a mean light level but will
yive act~ve data levels ~or either high or low phototran-
sistor volt~ge on sensors Fl-FlO. Thu~ it is po$sible
with one and the same electronics to sense hole codes and
"black points" codes.
As explained with reference to Fig. 5, the light
intensity ~rom lamp L5 is governed by a feedback loop. In
the pre~erred embodiment fox sensing dots or holes, there
is for each of channels Dl-D10 a special circuit. An
exemplary circuit is shown in Fig. 7, being mounted for
channel Dl. When in function, lamp LS is controlled so
that when a tag portion free of hole or dot is in front
of phototransistor FTl (782, its output signal is roughly
half the volt~ge available, i.e. about V~/2. The signal
from 78 is led to a window discrirninator 70. In this
circuit 70, there a~e two comparator circuits 72 and 73,
1,~
the positive inputs o~ which are biased by means of
a resistor chain 74-76 such that they receive about 2V+/3
and V~/3 respectively. If now the quiescent voltage at
about V+/2 prevails as input signal VF, comparator 72
will ~ive a high output signal and comparator 73 a low
output signal. These output signals Va and Vb are ]ed to
an EXCLUSIVE NOR/gate 71 and the result will be a low
output D1. If signal VF goes below V+/3 or goes higher
than 2V~/3, indicating a printed dot or a hole respective-
ly, gate 71 will in both cases deliver a high output
signal Dl. ~ignals Dl D10 are then treated as explained
for the case with holes only.
With this embod~ment, which is preferred at the
moment~ it is possihle to arrange in an extremely simple
way-fc)r marking down of prices. Such marking-down is
~abitually done ~or various reasons~ as for example when
an article is no longer available in all sizes or when
there is an annual sale Sometimes, a produGt may have
beaome shop~worn and cannot be sold at the originally
intended price. In al] such cases~ a sticker 50 (see
Fig. 3~ is af~ixed to the tag in a position near the
legible price 51. The sticker is provided with a border
which is e.g. as wide as two code holes. A discriminator
53 is activated from a reading sensor 52, functioning
the same way as sensors 18~ and will give off a signal
when finding such a border. This signal is used as a reject
signal, and the tag will be rejectecl, unless the changed
price was ~ntroduced on the keyboard be~ore the tag was
put in.
Sometimes, price tags are used which have a price
00.oo inscribed in the price code. The idea is to provide
the price at a later stage, although keepin~ the other
information available ~or registering. Thus~ the price is
marked only in eye-legible form~ In such a case, it is
3S neces$a~y to introduce a zero-pr:ice ~inding effect. This
is d~ne ~ providing the control lo~ic with a watch
funçtion which is set to ~ero when reading is commenced
and which is set as soon as a figure of 1-9 is read but
stays unset if there are only zeroes read. If thus, the
price is read as zero, the tag is rejected unless a price
is introduced by hand at the keyboard.
The electronic circuits now described in a pref~rred
embodiment built on a logic unit 33 which may be the
"Motorola Industrial Control Unit MC 14500B" described in
the "Motorola Handbook" for this one bit computer, printed
in 1977. The ROM for the program used should be programmed
according to the use described, a task well within reach
for an average electronician, as it is the choice of the
other hardware shown and described.
~,~d ,,
