GB2186405A

GB2186405A - Hand-held labeler having improved web position sensing and print head control

Info

Publication number: GB2186405A
Application number: GB08706381A
Authority: GB
Inventors: James Lacy Vanderpool; Jr Paul Helmut Hamisch; James Michael Bain
Original assignee: Monarch Marking Systems Inc
Current assignee: Avery Dennison Retail Information Services LLC
Priority date: 1984-04-03
Filing date: 1987-03-18
Publication date: 1987-08-12
Also published as: AU4001585A; GB8706385D0; GB2157039B; SG58289G; GB2186107B; FR2582096B1; HK12090A; JPH03124540A; GB2186107A; FR2575441A1; AU592725B2; GB2187318B; HK11790A; JPH0637205B2; HK11690A; GB2187583A; FR2575619A1; FR2575619B1; AU595472B2; AU2861289A

Abstract

A hand-held labeler, e.g. with a thermographic print head, senses the position of the web to control the position of the imprints on the web. A circular indexing member having a plurality of position defining indices provides indications representative of the position of the web. The indexing positions include at least one home position index (142) and a plurality of positioning indices (148) adjacent the home position index. A warning track (154) is provided ahead of each home position index. Relative rotation between the circular member and the shaft is prevented by a plurality of key slots or the like disposed on said circular member and engaging a key on the shaft. The angular spacing between the key slots is unequal and is substantially greater than the spacing between the positioning indices; but the position of the positioning indices relative to the shaft may be adjusted by a distance less than the distance between the positioning indices by bringing a different one of the key slots into engagement with the shaft. <IMAGE>

Description

GB 2 186 405 A SPECIFICATION adjacent to the label boundary defining index

that in forms the system that the label boundary is app Hand-held labeler having improved web position roaching. The indices are sensed by the sensor and sensing and print head control used to provide position indicative signals to the 70 system for controlling the operation of the printing This invention relates generally to printing devices, head.

and more particularlyto hand-held labelers utilizing Because of the precise positioning information circuitry accuratelyto determine the position of the provided bVthetiming disc, manufacturing tol printing web, and to control the operation of the erances become significant. Consequently, there is printing head, preferably a thermographic printing 75 preferably provided an adjusting mechanism for head, in response to position signals to thereby ac- adjusting the angular position of the timing disc re curately position the imprints on the web. lative to the feed mechanism. This is accomplished Hand-held labelers utilizing thermographic print- by permitting the disc to be positioned on the shaft ing devices are known. Examples of such hand-held driving the disc at a plurality of discrete angular posi labelers are illustrated in our United States Patents 80 tions, each associated with one of the home position Nos. 4,264,396 and 4,407,692, and United States indices. Such positioning can be accomplished by patent application Serial No. 485,012 filed April 14, providing a plurality of unequally spaced key slots or 1983 (see British Patent Application No. 2,138,190 the like in the disc, by providing a single key or spline published October 17,1984). on the shaftfor engaging one of the key slots. By While the devices disclosed in the above- 85 making the angular position of each key slot slightly described references do provide a way to make im- different relative to its associated home position prints on a thermosensitive web, they are capable of index and positioning indices, an adjustment can be improvement in certain respects. For example, when readily achieved by positioning the appropriate key printing with a thermal printing device, particularly slot overthe key orsplineto providethe desired with a high density printing device such as one of the 90 offset between the shaft and the disc.

devices illustrated in the aforementioned U.S. Patent The invention will now be described in more de No. 4,407,692 and British Patent Application No. tail, by way of example, with reference to the 2,138,190, it is necessary accuratelyto control the drawings, in which:

timing of the energization of the various printing el- Figure 1 is a perspective view of a hand-held lab ements as a function of the position of the web. For 95 eler constructed in accordance with the principles of example, in such a system, the web is continuously the present invention; fed, and the appropriate printing element must be Figure2 is a system block diagram of the logic cir energized at the precise time thatthe portion of the cuitry controlling the thermographic printing appar web on which the imprinting is desired is positioned atus according to the invention; adjacentthe printing head. The difficulty of the proFigure 3 is a plan view of a thermographic print blem is further compounded bythe fact that each of head usable with the printing apparatus according to the printing elements has a length and a width of the present invention; only a few mils. As a result, the position of the web or Figure 4 is a block diagram illustrating one emb the timing of the energization of the printing el- odiment of the print head driving circuitry; ements, must be precisely controlled to avoid print- 105 Figure 5is a block diagram of an alternative emb ing gaps and changes in print density, as well as odiment of the print head driving circuitry; changes in character shape, particularly when the Figure 6is a block diagram illustrating the position speed of the web varies as it passes the printing sensing and printer control circuitry according to the head, as for example, in the case of a labeler having a invention; hand advanced web. 110 Figure 7is a detailed illustration of the timing disc The invention in its various aspects is defined in illustrated in Figure 6; the appended claims to which reference should now Figure 8 is a block diagram of the motor speed con be made. trol portion of the control circuitry of the invention; In a preferred embodiment of the invention, there Figure 9 is a timing diagram illustrating the oper- is provided a hand-held labeler utilizing a micro115 ation of the motor speed control circuit according to processor-based control system that senses the pos- the invention; ition of the web and controls the operation of the Figure 10 is a logical flow diagram illustrating the printing head in accordance with the position of the operation of the control circuit according to the in web in orderto assure that any imprints are ac- vention; and curately positioned on the web, and on any labels cut 120 Figures 11 and 12 illustrate circuitry for protecting from the web. The system employs a precise timing the data stored in the labeler in the event of a dischar disc that is coupled to the label advancing mech- ged battery and when the battery is removed.

anism. The timing disc cooperates with a sensor, such as, for example, an optical sensorthat senses Detailed description of thepreferred embodiment the position of indices on thetiming disc, and prov- 125 Referring nowtothe drawing, with particular ides a signal representatixe of web position. Thetim- attention to Figure 1, there is shown a thermographic ing disc includes at least one and preferably more microprocessor-control led hand-held labelerac home position indices that defines the boundarybecordingtothe invention, generally designated bythe tween two successive labels, one or more position reference numeral 10. The labeler 10 includes a determining indices and a warning index disposed 130 housing 12 that supports a roll 14 of adhesive backed 2 GB 2 186 405 A 2 labels 16thatare supported on a backing web 18.A via a display driver 54. The display 24 is used to dis keyboard 20 is disposed on the housing 12 and con- play data being inputted into the microprocessor as tains a plurality of individually operable key switches well as other messages such, for example, prompt 22 for entering data into the labeler. A display 24, ing and diagnostic messages generated by the mic which may be a liquid crystal or light emitting diode 70 roprocessor. A read-only memory (ROM) 56 is prov display, is also disposed on the housing to permitthe ided for storing permanent data, such as the entered data and microprocessor-generated prom- program defining operation of the device. The read- pting instructions to be viewed bythe operator. A only memory 56 may either be permanently installed battery pack, which may be contained in a removable in the labeler 10, or may be removably installed in a battery pack-handle unit 25 containing a battery 26 75 socket orthe like to permitthe font and/orformatto having an internal resistance 27, provides electrical be changed by changing the memory 56. In addition, powerforthe labeler 10. Atrigger 28 is provided to a random-access memory (RAM) 58, usablefor stor initiate the label printing operation, and a label app- ing shortterm data, such as data entered via the key lying roller 30 is used to apply pressure to the adhes- board 20, is provided, as in a non-volatile random ive backed label 16 when the label 16 is being applied 80 access memory (NVRAM) 60, suitablefor storing to an article of merchandise. A label stripper (not data such as format data. The inputloutput connector shown) is contained within the housing 12 to sep32 provides communications between the device arate the labels 16 from the backing strip 18. A plura- and an external computer. Printing is accomplished lity of guide rollers are provided to guide the separ- by a print head assembly 64that contains a print ated labels 16 to the forward portion of the housing 85 head 66 and print head driver 68 coupled to the per beneath the label applying roller 30, and to guide the ipheral interface adapter40. An analog-to-digital backing stripto the rear of the housing beneath the converter70 coupled to the peripheral inter-face roll 14. adapter 40 senses the batteryvoltage orthevoltage As previously stated, the labeler according to the appliedtothe print head assembly64, and providesa invention is quiteversatile and iscapableof printing 90 digital indication of that voltage to the peripheral in alphanumerics, aswell as barcodes including the terface adapter 40 so thatthe microprocessor may Universal ProductCode (UPC) andthe EuropeanArt- adjust the time that the print head is energizedto icle Number(EAN). Thetypeof format,whether compensate for variations in battery or print head alphanumeric or bar code, is readilyselected byen- voltage.

teringthe appropriate format and fonts defining data 95 One example of the print head assembly 64 is illus via the keyboard 20. The data to be printedJor ex- trated in simplified form in Figure 3. In the illustrated ample, price, product defining data and other in- embodiment, the print head assembly 64 contains formation aboutthe product such as the size, color, the print head driver 68 and the print head 66 dis etc. is also entered via the keyboard 20. In addition, posed on a thin film substrate. The print head has a the number of labelsto be printed may be entered. 100 single line of print elements disposed transverse to Also, a data input/output connector 32, may be prov- the direction of travel of the web 18, and is part ided on the housing to permit data to be entered into icularly suitablefor use in a hand-held labeler be the labeler by an external source, such as, a re- cause of the high density of the print elements that motely-located computer, and to permitthe battery make up the print head 66, particularly if both alpha- 26 to be charged. 105 numerics and bar codes areto be printed. One print Referring to Figure 2, the keyboard 20 is coupled to head assembly particularly usable as the print head a peripheral interface adapter (PIA) 40 which prov- assembly 66 employs 224 printing elements that are ides an interface between various input and output each 10 mils long and 4.4 mils wide, and spaced on devices and a microprocessor 42. Also coupled to 5.2 mil centers. Such a configuration permits a virtu the peripheral interface adapter 40 are a trigger 110 ally continuous line to be printed.

switch 44 that is controlled bythe trigger 28, and a Each of the printing elements constitute a resistive control circuit 46that operates a motor 48 that drives heating element 80 (Figure 4) that is individually en a web advancing wheel 49. A detector 50 senses a erg izable by the print head driver circuitry 68 which mark or index on the web advancing wheel 49, or contains a heater driver transistor 82 for each of the preferably on a separate timing disc 51. The control 115 printing elements 80. A gate 84 controls each of the circuit46 responds to data received from the microheater driver transistors 82, and an input register 86 processor 42 and controls the operation of the web and a data register 88 control the operation of the advancing motor 48, which may preferably be a D.C. gates 84. Thus, if a 224-element head is used as the motor. An audible alarm 52 is also connected to the print head 66,224 driver transistors 82 and 224 gates peripheral interface adapter 40, and is useful for indi- 120 84 must be provided, and the input register 86 and cating to the operator that a problem or potential the data reg ister 88 must each have at least 224 st problem exists. For exam pie, the audible alarm 52 ages.

may be used to indicate a discharged or fau ity bat- The input register 86 receives data serially f rom a tery, a faulty print head, that the labeler is out of data input line 90 underthe control of clocksignals labels, ajam, or maysimply be used to indicatethat 125 applied to a clock line 92. When the input register86 data entered into the device has been received. Inthe isfull,the data istransferred in parallel to the data latter case,the audible alarm 52, can be used to pro- register88 underthe control of a latch signal applied vide an audible indication each time one of the key to the data register 88 by a line 94. The input register switches 22 on the keyboard 20 is depressed. 86 isthen reset by a reset pulse applied to the reset The display 24is coupled to the microprocessor 42 130line 96, and new data is upplied to the input register.

3 GB 2 186 405 A 3 Because the resistive heating elements 80 draw a the seven registers 86' contain the bits 1-32,33-64, substantial amount of current, for example, app- 65-96,97-128,129-160,161- 192 and 193-224. Since roximately 50 milliamps per element, and because of this data completely defines a line, the data from the the extreme density of the elements, for example, registers 86'can be transferred to a data register, approximately 200 elements per inch, the current 70 such as the data register 88 (Figure 4), orto a plurality drain on the battery 26 would be excessive if all of the of individual data registers 88' (Figure 5). The output elements 80 were turned on simultaneously. Forthis of the data register 88'can be applied to a plurality of reason, the heater driver transistors 82 are strobed three-inputAND gates 84, orto any suitable device bythe gates 84 so that no more than one-fourth of for limiting the number of individual elementsthat the heater drivers 82 may be energized at any one 75 can be simultaneously energized.

time. In Figure 5, the strobe function that limits the In the embodiment illustrated in Figure 4, the number of elements that can be simultaneously en strobing is accomplished by utilizing three input ergized is provided by a plurality of circuits 83. Each AND gates as the gates 84, and by enabling the gates of the circuits 83 contains 32 two-inputAND gates 84 in blocks. This is accomplished by providing two 80 and appropriate driving circuitry for driving the print block enable signals BE1 and BE2 on line 100 and head 66. Such a system is somewhat simplerthan 102, respectively, and strobes ST1 and ST2 on lines the system illustrated in Figure 4 because onlytwo 104and 106, respectively. Each of the blockenable inputAND gates, ratherthan three-inputAND gates, signals is connected to one-half of the gates 84so are required. By providing three strobe signals S1, that one-half of the gates 84 are enabled whenthe 85 S2 and S3,the number of printing elementsthatcan BE1 signals is high, and the other half are enabled be simultaneously energized is restricted to app when the BE2 signal is high. The ST1 signal is app- roximately one-third of the total numberof print el liedto one-half of the gates 84 receiving the BE1 ements.

signal and to one-half of the gates 84 receiving the In the embodiment illustrated in Figure 5, the BE2 signal. Similarly, the ST2 signal is applied to the 90 strobesignaIS1 is applied to the firsttwo and the last gates 84 not receiving the ST1 signal. Thus, since itis one of the circuits 83. The strobe signal S2 is applied necessaryfor each gate to receive one of the block to the third and fourth ones of the circuits 83, and the enable signals and one of the strobe signals in order strobe signal S2 is applied to the fifth and sixth ones to be fully enabled, only one-fourth of the gates 84 of the circuits 83. Consequently, no more than two are enabled at any given time. Thus, the data from 95 out of seven printing elements may be simu the data register 88 is applied to the heater driver ltaneously energized when eitherthe strobe signal transistors 82 in four steps, so that no more than one- S2 orthe strobe signal S3 is present. Theoretically, fourth of the transistors 82 may be energized at a as many as three out of seven elements may be en giventime. ergized when the strobe signal S1 is present, but in An alternative embodiment of the print head driv- 100 practice, the line of print is seldom as wide asthe ing mechanism is illustrated in Figure 5. The embodiwidth of the print head 66, and consequently, it is ment illustrated in Figure 5 is similarto the one illust- unlikelythat more than one-half of the total elements rated in Figure 4, exceptthatthe input register 86 is in the first and last ones of the circuits 83 would be broken up into a plurality of smaller registers, for ex- energized.

ample, seven 32-stage shift registers 86' in the illust- 105 The control circuit46 (Figure 6) includes a control rated embodiment. Such an arrangement hasthe processor 130that includes a read-only memory advantagethat it permits data to be entered more (ROM) 132that may be located either on the same rapidly into the system, thereby permitting a faster integrated circuit asthe control processor 130 or in a printing speed. This occurs because each of the separate package. The various components required seven shift registers 86'can be fed in parallel from 110 to carry out the print control function are not shown said seven separate data lines 90'. Consequently, the in Figure 6 for purposes of clarity; however, it should data need be shifted only 32 times to load the regis- be understood that the microprocessor 42 of Figure 6 ters 86', as opposed to the 224 shifts required to load must be coupled to components that are the same or the input register 86. However, when loading the analogous to the components shown in Figure 2 to shift registers 8Wand 224 bits defining each line 115 provide the printing function. The control processor cannot be fed serially into the shift registers 86', but 130 controls a motor drive/brake circuit 134that the bits must be grouped so thatthey may be applied selectively applies energizing or dynamic braking to the appropriate registers. This is accomplished by currents to the motor48. An analog-to-digital con taking every 32nd bit from the data defining a line, verter 136 measures the back EMF of the motor48 and applying itto the appropriate one of the shift re- 120 when it is coasting, and applies a digital representa gisters 86'. For example, if 224 bits are used to define tion of the back EM17to the control processor 130 in a line, the 32nd, 64th, 96th, 128th, 160th, 192nd and orderto provide an indication of the speed of the 224th bits are selected and applied to seven stages of motor48 to the control processor 130. The detector a buffer 108 (Figure 5). These bits are then applied in 50 includes a light source, such as, for example, a parallel to the shift registers 86'. Next, the 31 st, 63rd, 125 light emitting diode 138 and a light sensitive device 95th, 127th, 159th, 191 st and 223rd bits are applied to such as a photodetector 140 disposed on opposite the buffer 108 and shifted to the registers 86'. The sides of the timing disc 51. The detector 50 servesto process is repeated until the first, 33rd, 65th, 97th, detect indices formed as a series of light contrasting 129th, 161 st and 193rd bits are loaded into the buffer marks such as opaque an.d transparent portions on 108 and supplied to the registers 86'. At this point, 130 the disc 51. Preferably, the indices are fabricated as a 4 GB 2 186 405 A 4 series of apertures about the periphery of the disc 51 ment that is equal to an integral multiple of the which are used to indicate to the system the position length of the print elements 80. For example, when a of the disc 51, and consequently, the position of the printing head such as the previously described print web 18 as it is advanced bythe advancing wheel 49. ing head 66 is used, the distance between the detec Although, an optical system is used to detectthe 70 tion of adjacentedges of the slots 148,150 and 152 position of the disc 51, othersystems may also be correspondsto a webtravel that is equal to an in used. tegral multiple of 10 mils (the length of the printel Thetiming disc51 is illustrated in greaterdetail in ements80). In thetiming disc51 illustrated in Figure Figure7.The disc illustrated in Figure7 isfabricated 7,the integral multiple has been selectedto beequal from an opaque material. Because of the relatively 75 to two, thus providing a web travel of 20 mils be small size of the disc 51, for example, on the orderof tween the detection of successive edges of the slots approximately 1.25 inches in diameter, and because 148,150 and 152. As a result, the position of theweb of the precise tolerances required, the use of electro- 14 is defined in 20 mil increments.

deposited nickel provides a convenientwayto fabri- The width of each of the warning tracks defined by cate the disc. The thickness of the disc 51 is nomi- 80 the widened areas 154,156 and 158 must be made nally 3 mils, but may vary from 2 mils to 4 mils. wide enough to permit the warning tracks to be dis As is illustrated in Figure 6, the disc 51 is mounted ting uished from the areas between the position def on the same shaft (shaft 141) as is the web advancing ining slots. In the embodiment illustrated in Figure 7, wheel 49 and rotates therewith to form a shaft enco- the width of the areas 154,156 and 158 is selected to der. In the il lustrated em bodiment, the wheel 49 85 be approximately twice as wide as the widths of the rotates one-third of a revolution each time a com- areas separating the slots 148,150 and 152. This pro plete label isfed. Three home position indices in the vides a warning track having a width that cor form of three apertures 142,144 and 146 are prov- responds to approximately fourtimesthe length of ided in the disc 51. In the illustrated embodiment, the printing elements 80, or approximately40 mils.

three home position indices are provided because 90 The width of the areas 154,156 and 158 is selected the disc 51 rotates one third of a revolution each time such thatthe areas 154,156 and 158 can be readily a label isfed; however, itshould be understoodthat distinguished from the narrower areas separating if the advancing mechanism were modified such that the slots 148,150 and 152, and although in the emb the disc 51 rotated at a different rate, the number of odiment illustrated in Figu re 7, the widened areas home position indices would have to be changed ac154,156 and 158 have been selected to be app cordingly. For example, if the disc 51 rotated one roximatelytwice as wide asthe areas separating the fourth of a revolution each time a label was fed, a slots 148,150 and 152, otherwidths may be used.

discwith four home position indices would be used. In operation, when the labeler is not printing a Following each of the apertures 142,144 and 146 is label, one of the home position defining indices, for a plurality of position defining indices in the form of a 100 example, the aperture 142 is aligned with the detec plurality of apertures or slots 148,150 and 152, re- tor 50. When the trigger switch 44 (or other manually spectively (Figure 7), which accurately definethe operable switch) is depressed, the microprocessor position of the label with respectto the printing 42 (Figure 6) issues a start motor command to the head. Although the position defining indices 148,150 control processor 130 which in turn rendersthe and 152 can be referred to as either apertures or 105 motor drive/brake circuit 134 operative to energize slots, or by otherterminology they will be referred to the motor 48. The light-emitting diode 138 is also en as slots in the following description for purposes of abled. When the motor 48 is energized, the timing clarity in orderto better distinguish them from the disc 51 is rotated in the direction shown bythe home position apertures 142,144 and 146. Awarning arrows in Figures 6 and 7. Asthe motor rotates, any track is provided ahead of each of the home position 110 slack present i n the web 18 and any backlash in any indices in the form of three widened areas 154,156 of the web advancing mechanism is taken u p while a and 158. portion of the aperture 142 is still aligned with the When no labels are being printed, one of the home detector 50. The motor 48 continuesto rotate until positon defining apertures 142,144, or 146 is aligned the trailing edge of the aperture 142 is detected by with the sensor 50. Each of the apertures 142,144, 115 the detector 50. Atthis point, all slack in the system and 146 is sufficiently wide to permitsome backlash has been taken up and the motor48 is upto operat in theweb and drivetrain to occur without causing ing speed.

an opaque area of the disc 51 to be detected bythe When the trailing edge of the aperture 142 is detec sensor 50. This prevents the motor48 from hunting ted bythe detector 50, the amplitude of the signal in an attemptto keep one of the home position aper- 120 applied to the photodetector 140to the control pro tures aligned with the sensor 50. The size of the apercessor 130 changes. The control processor 130 re tures 142,144 and 146 is also selected to permit any sponds to this change by issuing a start print com slack in the web 18to be taken up before one of the mand to the microprocessor 42. The start print signal position defining indices is moved into alignment indicates to the microprocessor 42 thatthe motor is with the detector 50. 125 up to speed and the web is positioned to accept print The width of the position defining slots 148,150 ing atthe printing positions defined bythe selected and 152 and the width of the areas between the posi- printformat.

tion defining slots is selected such thatthe distance As the motor48 continues to rotate, thetransitions between the detection of successive edges of the between the slots 148 and the opaque areas dis slots 148,150 and 152 corresponds to a web move- 130 posed therebetween are aetected by the photodetec- GB 2 186 405 A 5 tor 140, and signals representative of the transitions andthedisc51 provided with a single keyslot or slot are applied to the control processor 130. The control engaging member. Othervariations could be used.

processor 130 respondsto the transitions and gener- In the illustrated embodiment, this is accomplished ates a position pulse signal and applies itto the mic- by mounting the timing disc 51 on a keyed shaft and roprocessor42 each time a transition occurs. The 70 providing a plurality of offset keyslots on the disc 51.

position signals are counted bythe microprocessor Each of the offset keyslots is associated with one of 42 in orderto determine the position of the label with the home position indices 142,144 and 146 and is respectto the print head 66. When the print head 66 offsettherefrom bythe amount of adjustment requi is positioned over a print area of the label, as defined, red. Thus, any required adjustment may be obtained for example, by the printformat, the entered data is 75 by positioning the appropriate slot on the key of the printed on the labels 16. The process continues with shaft.

the microprocessor 42 receiving position pulse Forexampie, in thetiming disc illustrated in Figure signaisfromthe control processor 130 until the ente- 7,three keyways captioned 1, 2 and 3 areshown.The red data is printed on one or more print areas of the angular displacement between the keyways 1 and 3 labels 16. 80 is nominally 122', while the angular displacement Asthe printing process continues, thetiming disc between the keyways 1 and 2, and 2 and 3 is nomi- 51 continuesto rotate until the warning trackclefined nally 119'. This compares with a 120'angulardis bythe widened area 154 is detected. Thewidened placement between the leading edges of the aper area 154 is detected by the control processor 130 tures 142,144 and 146, and permits a -L 1'adjustment when the length of time that an opaque area is being 85 ofthedisc51 relative to the web advancing wheel 49 detected by the photodetector 140 exceeds the and the detector 50.

length of time between the transition pulses gener- If for exam pie, the keyway designated by the nu m ated by the slots 148 by a predetermined amount. eral 1 were keyed to the shaft 141 by a key 160, the Once it has been determined that a warni ng track trailing edge of the aperture 142 wi 11 lead the center such as the area 154 has been detected, the m icro1 ine of the key 160 by approximately 2% The 2'offset processor is conditioned to respond to the next shall be called the minus 10 position.If the keyway transition by rendering the motor drive/brake circuit captioned bythe numeral 3 is keyed to the key 160, 134 operative to brake the motor 48. Thus, when the because the keyways 1 and 3 are spaced by 122',the leading edge of the aperture 144 is detected, a brake trailing edge of the aperture 144will lead the center signal is applied tathe motor drive/brake circuit 134 95 of the key 160 by 4,thus resulting in a positive 2o to causethe motor drive/brake circuit 134to shunt shift in the position of the positioning slotswith re the armaturewinding of the motor48to thereby dyn- specttothe minus 1'position. Adding 20to minus 10 amically brakethe motor48. The motor48 continues results in positive 1', so this position can be conside to coastfor a short distance until the aperture 144 is red the plus 1'position. If the keyway captioned by aligned with the detector 50, and the printing process 100 the numeral 2 is keyed to the key 160, the disc 51 will is terminated. If it is desired to print another label, the have been rotated a total of 122'plus 11 9'or 241' trigger switch 44 is again depressed and another relative to its position when keyed to keyway number label is printed as the disc 51 is advanced until the 1, thus resulting in a positive 1'shift in the position of aperture 146 is aligned with the detector 50. the positioning slots relative to the minus 11' position.

Also, although the timing disc 51 isshownincon- 105 Thus, this position becomes the zero degree posi- junction with a motor.driven advancing mechanism, tion, and positive and negative 1 degree adjustments it may also be used in conjunction with a hand or ofthedisc51 relative to the zero degree adjustments manually operated advancing mechanism. In such of the disc 51 relative to the zero deg ree position may an event, even thoug h the signals provided by the be readily attained. Other adjustments may be timing disc 51 would not be used to control a motor, 110 achieved by altering offsets between the keyways 1, the position signals would still be used to indicate to 2 and 3. For example a 2'adjustment by spacing the microprocessor when a printable area is beneath the keyway captioned 3 by 124'from the keyway cap the print head, and cause printing to be initiated tion 1, and by spacing the keyway captioned 2 by when such an area is present. 1118'from the keyways captioned 1 and 3. In general, As previously stated, the timing disc 51 provides 115 any offset may be achieved by appropriately spacing very accurate information defining the position of the keyways 1 and 3 by total desired positive and the web. However, in orderto make use of the ac- negative offset added to 1200. If equal positive and curate position signals provided bythetiming disc negative offsets are desired, such equal positive and 51, it is necessaryto compensate for manufacturing negative offsets may be achieved by dividing the re tolerances present in the web advancing mechanism 120 mainder of the 360'are between the keyways cap and in the positioning of the print head 66. Consequ- tioned 2 and the keyways captioned 1 and 3.

ently, in accordance with another aspect of the pre- Although various types of motors, including step sent invention, there is provided a wayto alterthe ping motors, are usable as the web advancing motor angular position of the timing disc 51 with respectto 48, it has been found that a D.C. motor is particularly the angular position of the web advancing wheel 49. 125 useful as the web advancing motor 48, partly be Various other keying means could be used to affix cause of its good low speed torque characteristics.

the disc 51 to the shaft. For example, a slot could be Howeverwhen a D.C. motor is used, it is necessaryto provided on the shaft, and slot engaging members provide circuitry for controlling the speed of the could be provided on the disc. Alternatively, the shaft motor shaft. In the presen ' t embodiment, the motor could be provided with a plurality of keys or keysiots, 130 speed control is provided by the c6ntrol processor 6 GB 2 186 405 A 6 130. As previously discussed, the control processor motor 48 is not immediately sampled because it is receives signals representative of the back EM F not representative of the back EM F being generated generated by the motor 48 when it is coasting, and by the motor. Instead, the sampling is delayed until a adjusts the drive signal applied to the motor 48 to sampling period 182 that follows thetime2T by a thereby maintain the speed of the motor 48substan- 70 time interval sufficientto allow the transient to die tiallyconstant. down. It has been determined that delaying the sam Referring to Figure 8, the motor 48 is driven bythe pling period 182 for approximately 300 micro motor drive/brake circuit 134which includes a trans- seconds following thetermination of a run pulse istor drive circuit 170 that applies an energizing pot- allows enough of the transientto die down to permit ential to the motor 48 when a run signal is received 75 an accurate reading of the back EMF of the motor48 from the control processor 130. An interlock circuit to be made; however, the delay time is dependent on prevents both the run and brake signals from being the size and inductance of the motor, as well as other applied to the drive/brake circuit 134 simultaneously factors, and other values may be used depending on in the eventof a microprocessor or other malfuncthe particular components used. The sampling is tion. The motor drive/brake circuit 134 also includes 80 done underthe control of the sampling gate 176 a dynamic braking circuit 172 that shuntsthe arma- which is enabled during the sampling period 182 and ture of the motor48 to provide dynamic braking othersampling periods bythe microprocessor 130.

when a brakesignai is received from the control pro- If the back EMF measured during the sampling cessor 130. Acomparator 174is connected tothe period 182 istoo low, another run pulse 184 is gener- motor48 and servesto comparethe back EM17gener- 85 ated during thetime interval between 3Tand 4T, and ated bythe motor48when it is coasting with a refer- the back EMF is again sampled during a sampling ence voltage. A sampling gate 176 couplesthe period 186 occurring priorto the time 5T. If the back output of the comparator 174to the control pro- EMF during the sampling period 186 is again too low, cessor130. another run pulse will be generated attime 5T; how The run signal applied to the drive circuit 170 inclu- 90 ever, if the back EMF is higherthan the reference vol des a series of pulses which causethe drive circuit tage, no run pulse will be generated attime 5T, as is 170to energizethe motor48 at periodic intervals. illustrated in Figure 9. Rather, the back EMF will be The back EIVIFgenerated by the motor48 between sampled during a subsequent sampling interval 188 drive pulses is sampled bythe comparator 174 and priorto thetime 6T, and if the back EMF has dropped the sampling gate 176,which operate as an analog- 95 belowthe reference voltage, another run pulse 190 to-digital converter,to indicate to the control pro- will be generated atthe time 6T. The process will be cessor 130 whetherthe back EMF generated bythe repeated at periodic intervals with the run pulses motor48 is greaterthan or less than the reference being eliminated as required to maintain the speed voltage applied to the comparator 174. If the back of the motor 48 substantially constant.

EMF is lessthan the reference voltage, the next run 100 Referring nowto Figure 10, when the labeler is init pulse is generated by the control processor 130 ially energized, the parameters in the micro again to energize the motor 48. If the back EMF gene- processor 42 and the control processor 46 are init rated bythe motor 48 is greaterthan the reference ialized, and the control processor 46 is conditioned voltage, indicating thatthe speed of the motor is ex- to initiate thefeeding of the web upon receipt of a cessive, the next run pulse is eliminated, and the 105 start pulse from the microprocessor 42. Upon receipt motor is allowed to coast. During the coasting period of a start pulse, a clock in the control processor 46 is the back EMF is measured at periodic intervals until it resetto zero. Subsequently, a separate timer is upda drops belowthe reference voltage, atwhich point an- ted to indicate how many times the control processor other run pulse is generated. The speed of the motor clock has been reset. This provides an indication of may be adjusted by adjusting the reference voltage. 110 how long the motor 48 has been running. If thetime The run pulse generation and back EMF sampling exceeds a predetermined limit, the run timertimes is illustrated in greater detail in Figure 9. Referring to out, the motor is stopped and braked, and the control Figure 9, the back EMF is sampled during a first sam- processor 46 is conditioned to awaitthe next start pling period 179 occurring during a portion of the pulse. A signal may also be sentto the audio alarm time interval ranging from.zero to T. If the back EMF 115 52 to indicate a jam. If no timeout occurs, the detec is less than the reference a run pulse, as illustrated by tor 50 is sampled to determine whether a start print the pulse 180 is generated during the time interval edge (first opaque edge after home position between T and 2T. The duration of the pulse 180 is aperture, Figure 7) has been encountered. If the edge controlled bythe clock (not shown) in the control has been detected, a start print pulse is seritto the processor 130, and is preferably on the order of 500 120 microprocessor 42, and the condition of the motor is microseconds to 1 millisecond. No sample is taken checked, as is described later. If the edge passed pre during the time interval between T and 2T because viously, the timing disc is checked for a position such a sample would be meaningless because all index. If a position index is detected, a position pulse thatwould be measured would be the amplitude of is sentto the microprocessor 42. If no index is detec- the pulse 180. 125 ted,thetiming disc is checked forthe presence of the Afterthe run pulse 180 has been terminated atthe warning track (widened opaque area, Figure 7). The time 2T, the drive to the motor48 is also terminated; widened area can be readily determined bythe however, the termination of the drive to the motor 48 length of time it is aligned with the sensor 50. When results in a transient across the armature winding of the end of the warning track is detected, the motor is the motor 48. Consequently, the voltage across the 130stopped, the brake is turned on fora predetermined 7 GB 2 186 405 A 7 time interval, and the control processor is con- that compares the voltage atthe battery 26 with a low ditioned to awaitthe next start motorcommand. battery voltage reference. In the everitthatthe vol The purpose of the above-described steps is to det- tage provided bythe battery 26 drops below the low ermine the position of the timing disc, and hence the battery reference potential, the comparator 200 app position of the label during the printing cycle. In 70 lies a signal to the microprocessor 42 and to the con addition to determining the position of the label,the trol processor46 in orderto putthe processor in a speed of the motor must be determined. In the logic resetcondition to prevent erratic operation thereof.

diagram illustrated in Figure 10, the motorspeed In addition,the comparator 200 applies a disabling check is made subsequentto each position cheek. signal to the RAM 58 and the NVRAM 60 to prevent Thus, if the run timer has nottimed out, and the end 75 data from being written onto orerased from the of thewarning track has notyet been detected, a RAMs. Adisabling signal is also applied to the print motorspeed check is made. This is accomplished by head 64to clamp the print head driver 68 to thereby first checking the motorto see if it is on or off. If the prevent energization of the print head 66. Thus, the motor is off, the system waits until a sampling period RAMs and the print head are effectively protected is reached. When the sampling period is reached,the 80 from erratic operation of the microprocessors.

back EMF is checked to determine motor speed. The In orderto preveritthe loss of data from a non result of the check, indicating whetherthe motor volatile read-only memory such as the NVRAM 60, a speed is too fast ortoo slow, is stored. If the motor is back-up battery, such as, for example, a lithium bat on, no speed check can be made, and the motor is tery 210 (Figure 12), is provided. The use of a lithium turned off. 85 battery for such a purpose is particularly advantag Afterthe back EM F has been checked, or afterthe eous because such batteries have a relatively long motor has been turned off, the system waits forthe shelf life, on the order of approximately ten years.

processor clockto reach time. T, that is, the nexttime However, if the lithium battery were used to power at which a run pulse can be generated. When the the NVRAM for extended periods of time, itwould time T is reached, the stored result is checked to det- 90 become discharged relatively rapidly. Therefore, ermine whetherthe motor speed was too slow. If the some means must be provided to preveritthe back motorspeed had been too slow,the motor isturned up battery 21 Ofrom discharging prematurely. Thus, on,the control processor clock is resetto zero,the when the labeler is turned on,the NVRAM 60 is pow run time is updated to include the time accumulated ered from the main battery, such asthe battery 26; bythe processorclock during the last cycle, and the 95 however, some provision must be provided to power cycle is repeated. If the speed of the motor was not the NVRAM 60 when the labeler is stored in an off too slow,the motor is notturned on before the pro- condition for an extended period of time.

cessor clock is resetto zero and the run timer upda- In the hand-held labeler according to the inven ted. In the everitthatthe motorwas previously on, tion, the labeler circuits are powered by the battery and no back EMF cheek was made and stored, it is 100 26 which is connected to a voltage regulator 212 via assumed thatthe motor speed was nottoo slow and an on-off switch 214 (both not shown in Figure 2).

the processor clock is resetto zero withoutturning The regulator 212 provides a regulated voltage, for on the motor. Because the motor is now off, a speed example, 5.6 volts, to the labeler circuits when ever check can be readily made during the next cycle. the on-off switch 214 is closed. Underthese con As previously discussed, the labeler according to 105 ditions, the output voltage of the regulator 212 is the invention is a hand-held labelerthat is powered applied to the NVRAM 60 by means of a blocking by a battery. As in the case of all battery-powered diode 216, and the NVRAM is powered by the battery devices, the voltage applied to the various circuits 26 via the switch 214, the regulator 212 and the diode drops as the battery discharges, and may even reach 216 wheneverthe labeler is operating. A diode 211 zero when the battery is completely discharged or is 110 isolates the battery 210 from the rest of the circuitry removed. Such voltage variations can cause serious underthese conditions because the voltage applied problems. For example, when the voltage applied to to the NVRAM 60 is higherthan the voltage of the a microprocessor drops below a predetermined battery 210, and the diode 211 is reverse biased.

level, the operation of the microprocessor becomes When the labeler is turned off, the output voltage erratic. When this occurs, the erratic signals from the 115 of the regulator 212 is zero, and consequently, if the microprocessor can alter or erase the data stored in labeler is stored for an appreciable length of time, the various memories. The processor can also cause the back-up battery 210 will eventually discharge if damage to the print head, for example, by con- the regulator 212 were relied on to powerthe tinuously energizing one or more of the printing el- NVRAM 60. Therefore, in accordance with another ements. In addition, when a non-volatile RAM, such 120 important aspect of the present invention, there is as the NVRAM 60, is used, a drop or loss of battery provided an auxiliary circuitthat powers the NVRAM voltage can cause the data stored in the NVRAM to 60 even when the labeler is off. The auxiliary circuit be lost. includes a Zenerdiode 218that is coupled to the bat Thus, in accordance with another aspect of the pre- tery side of the switch 214 by a resistor 220. The jun- sent invention, there is provided a circuit (Figu re 11) 125 ction of the resistor 220 and the Zener diode 218 is that monitors the voltage produced bythe main bat- coupled to the NVRAM 60 by another blocking diode tery, such as, the battery 26, and protects thevarious 222. Thus, when the switch 214 is open, the NVRAM memories and the print head in the event of a low 60 is powered by the auxiliary circuit. As in the case battery condition, and in the everitthatthe battery is when the switch 214 is on, the diode 211 isolates the removed. This is accomplished by a comparator 200 130battery 210 from the rest of the circuitry as long as 8 GB 2 186 405 A 8 the battery 26 is present and active. By making the coupled to said data entering means for electrically voltage of the Zener diode 218 lowerthan the output processing the selected data and energizing the indi voltage of the regulator 212, for example, 4.2 volts, vidual print elements in a predetermined sequence interaction between the two circuits is eliminated. determined by the selected data to print data on the For example, when the switch 214 is closed, thevol- 70 label, wherein said advancing means includes inde tage appearing atthe cathode of the blocking diode xing means coupled to said processing means for 222 is greaterthan the voltage appearing at its providing signals representative of the position of a anode. This reverse biases the diode 222 and pre- label to said processing means, said indexing means vents currents from flowing from the regulator 212 including at least one home position index and a into the Zener diode 218 and discharging the battery 75 plurality of position indices disposed adjacent said 26. When the switch 214 is open, the blocking diode home position index.

216 is reverse biased, thus preventing the labeler cir- 2. A hand-held labeling machine as recited in cuitry from discharging the batteries 26 and 210. If claim 1 wherein indices are disposed on a disc.

the battery 26 is removed, or becomes discharged, 3. A hand-held labeling machine as recited in thediode211 becomes forward biased and the 80 claim 2 wherein said indices are light contrasting in NVRAM 60 is powered by the battery 211. Under dices.

these conditions, the diodes 216 and 222 isolate the 4. A hand-held labeiing machine as recited in battery 211 ffom all of the labeler circuitry otherthan claim 3 wherein indices are formed by apertures the NVRAM 60. formed in said disc.

Thus it is seen thatthe hand-held labeler described 85 5. A hand-held labeling machine as recited in includes a system for precisely sensing the position claim 4wherein the aperture forming said home pos of the web, for adjusting the position of the web re- ition index is larger than the apertures forming said lative to the printing device with great accuracy, and position indices.

forcontrolling the energisation of the printing el- 6. A hand-held labeling machine as recited in ements in accordance with the web position in order 90 claim 5 wherein said disc includes a plurality of to position the imprints on the web with this ac- home position indices and wherein said position in curacy. The web position sensing system is part- dices are interposed between said home position in icularly usable with a thermographic printing device, dices.

and minimisesthe possibility of damage to the print- 7. A hand-held labeling machine as recited in ing device. The web positioning device positions the 95 claim 6 wherein said disc includes areas having a web to an accuracy of a few mils and provides a predetermined width separating said position in ready positioning adjustmentthat is also accurateto dicesfrom each other, said discfurther including an within a few mils. Theweb can be readily re- area having a width greaterthan said predetermined positioned with an accuracy of a few milsto corn- width separating said position indicesfrom one of pensatethe manufacturing tolerances. The system 100 said home position indices.

controlsthe printing deviceto compensate for vari- 8. A hand-held labeling machine as recited in ations in the speed of the web, and is usable with claim 7 wherein said disc is fabricated from electro hand advanced and motorised web advancing mech- deposited nickel.

anisms. 9. A hand-held labeling machine as recited in Obviously, many modifications and variations of 105 claim 1 wherein said home position index is larger the present invention are possible in light of the than said position indices.

aboveteachings. Thus, it isto be understood that, 10. A hand-held labeling machine as recited in within the scope of the appended claims, the invenclaim 9 wherein said indexing means includes a tion maybe practiced otherwise than as specifically pi u rality of home position indices and wherein said described above. 110 position indices are interposed between said home position indices.

Claims

CLAIMS 11. A hand-held labeiing machine as recited in claim 10 wherein

said indexing means includes 1. A hand-held labeling machine comprising; a areas having a predetermined width separating said housing having a manually engageable handle,the 115 position indicesfrom each other, said indexing housing having meansfor holding a label supply roll meansfurther including an area having a width grea of a compositeweb having labels releaseabiy adhe- terthan said predetermined width separating said red to a backing strip, meansfor printing on a label at position indicesfrom one of said home position in a printing position, meansfor peeling the printed dices.

label from the backing strip, label applying means 120 12. A timing disc for providing signals represent disposed adjacent the peeling means, means for ative of the position of a shaft comprising: a disc hav advancing the web to peel a printed label from the ing a plurality of home position apertures having a backing strip atthe peeling means and advance the predetermined width formed aboutthe periphery printed label into label applying relationship with the thereof, said discfurther including a plurality of posi- label applying means and to advance another label 125 tioning apertures interposed between said home into the printing position, means for entering selec- position apertures, said positioning apertures hav ted data to be printed, the printing means including a ing a width that is narrowerthan the width of said thermographic print head having a plurality of indi- home position apertures.

vidually selectable print elements for printing on a 13. A timing disc as recited in claim 12 wherein thermographic label ata printing position, means 130 said positioning apertures are separated from each 9 GB 2 186 405 A 9 other by a plurality of areas having a predetermined claim 17 wherein said first means is operative to pro width, and wherein said disc includes an extended vide the highestvoltage to said memory, said second width area having a width greaterthan said pred- means is operative to provide an intermediate vol etermined width separating said positioning aper- tage, and said third means is operative to providethe tures from one of said home position apertures, 70 lowestvoltage.

14. Atiming disc as recited in claim 13 wherein 19. A hand-held labeling machine as recited in said predetermined width is equal to the width of the claim 16 wherein said isolation means includes a positioning apertures, and wherein the width of said plurality of diodes.

extended width area is approximately twice said pre- 20. A system for controlling the speed of an elec- determined width. 75 tric motor, comprising:

15. A timing disc as recited in claim 14 wherein means for providing an energizing pulse to said el the width of said home position apertures is greater ectric motor; than the width of said extended width area. means for providing a predetermined time delay 16. A hand-held label ing machine comprising; a following the termination of the energizing pulse; housing having a manually engageable handle, the 80 means responsive to the delay means for sampl housing having means for holding a label supply roll ing the amplitude of the back EM F generated by the of a composite web having labels releaseably adhe- electric motor after a predetermined delay following red to a backihg strip, a battery contained within said the termination of the energizing pulse; housing, means for connecting a source of electrical means for comparing the amplitude of the samenergyto said labeling machine, an on-off switch in- 85 pled back EMF with a predetermined amplitude; and terposed between said connecting means and said means responsive to said comparing meansfor labeling machine and having a firstterminal connec- generating another energizing pulsewithin a second tedto said connecting means and a secondterminal predetermined time interval if theamplitude ofthis connected to said labeler, meansfor printing on a backEMFis belowthe predetermined amplitude.

label ata printing position, meansforpeeling the 90 21. A system as recited in claim 20 further includ printed label from the backing strip, label applying ing means responsiveto said comparing meansfor means disposed adjacentthe peeling means, means preventing the generation of another energizing for advancing the webto peel a printed label from pulsewithin the second predetermined time interval the backing strip atthe peeling means and advance if the amplitude of the back EMF is abovethe pred- the printed label into label applying relationship with 95 etermined amplitude.

the label applying means and to advance another 22. A system as recited in claim 21 wherein said label into the printing position, means for entering comparing means includes an analog comparator.

selected data to be printed,the printing means in- 23. A system as recited in claim 22 wherein said cluding athermographic print head having a pluracomparing means responsive means includes a lity of individually selectable printelements powered 100 digital sampling means responsiveto said delay bythe source of electrical energyfor printing on a means.

thermographic label atthe printing position, means 24. A hand-held labeling machine comprising; a coupled to said data entering means for electrically housing having a manually engageable handle, the processing the selected data and energizing the indi- housing having means for holding a label supply roll vidual print elements in a predetermined sequence 105 of a composite web having labels releasably adhered determined by the selected data to print data on the to a backing strip, means for printing on a label at a label, said processing means including memory printing position, means for peeling the printed label means of the type requiring the continuous applica- from the backing strip, label applying means dis tion of electrical energythereto to maintain the posed adjacentthe peeling means, meansforadvan memoryfunction, circuit means having first means 110 cing thewebto peel a printed label fromthe backing electrically coupled to said firstterminal forapplying strip atthe peeling meansand advancethe printed electrical energyfrom said sourceto said memory label into label applying relationship with the label means when said on-off switch is on, said circuit applying means and to advance another label into means having second means electrically coupled to the printing position, means for entering selected said second terminal for applying electrical energy 115 data to be printed, the printing means including a from said source to said memory means when said thermographic print head having a plurality of indi on-off switch is off, said circuit means further includ- vidually selectable print elements for printing on a ing third means electrically coupled from said bat- thermographic label at a printing position, means teryfor applying electrical energyf rom said battery coupled to said data entering means for electrically to said memory means when said source is inoperat- 120 processing the selected data and energizing the indi ive or disconnected from said labeiing machine, said vidual print elements in a predetermined sequence circuit means including isolation means for isolating determined by the selected data to print data on the said first, second and third means so that said bat- label, said advancing means including means for tery is operative to provide electrical energy onlyto providing a plurality of pulses representative of the said memory means. 125 position of the label, and jam detecting means in 17. A hand-held labeling machine as recited in cluding timing means responsive to said pulses and claim 16 wherein said first, second and third means for providing an indication of a jam if a complete are operative to provide three different voltages to label is not advanced within a predetermined time said memory means. interval.

18. A hand-held labeling machine as recited in 130 25.A hand-held labeling machine as recited in GB 2 186 405 A 10 claim 24wherein said position representative pulse ergizing the individual print elements in a predproviding means includes a shaftencoder. etermined sequence determined bythe selected data 26. A hand-held labeleras recited in claim 25 to print data on the label, wherein said advancing wherein said shaft encoder includes an index repre- means includes indexing means having a home pos sentative of the end of a label, said jam detecting 70 ition index and a plurality of position indices, and means being responsive to said end of label repre- means for detecting said indices, said indices being sentative index forterminating the operation of said selectively alignable with said detecting means, said timing means upon detection of said end of label home position index being largerthan said position index. indices and having a predetermined size selected so 27. A hand-held labeling machine comprising; a 75 that at least a portion of said home position index housing having a manually engageable handle, the remains aligned with said detecting means upon the housing having means for holding a label supply roll backlash of said advancing means.

of a compositeweb having labels releasably adhered 30. A hand-held labeling machine as recited in to a backing strip, means connecting a source of el- claim 29 wherein said indices are disposed on a disc.

ectrical energy to said labeler means for printing on a 80 31. A handheld labeling machine as recited in label at a printing position, means for peeling the claim 29 wherein said indices are light contrasting printed label from the backing strip, label applying indices.

means dispos'ed adjaceritthe peeling means, means 32. A hand-held labeling machine as recited in for advancing the web to peel a printed label from claim 31 wherein said indices are formed by aper- the backing strip at the peeling means and advance 85 tures formed in said disc.

the printed label into label applying relationship with 33. A hand-held labeling machine as recited in the label applying means and to advance another claim 32 wherein said disc includes a plurality of label into the printing position, means for entering home position indices and wherein said position in selected data to be printed, the printing means in- dices are interposed between said home position in cluding a thermographic print head having a plura- 90 dices.

lityof individually selectabie printelements powered 34. A hand-held labeling machine as recited in by the source of electrical energy for printing on a claim 33 wherein said disc includes areas having a thermographic label at a printing position, means predetermined width separating said position in coupled to said data entering means for electrically dices from each other, said disc further including an processing the selected data and energizing the indi- 95 area having a width greaterthan said predetermined vidual print elements in a predetermined sequence width separating said position indices from one of determined bythe selected data to print data on the said home position indices.

label, meansfor monitoring thevoltage provided by 35. A hand-held labeling machine as recited in the source of electrical energy for preventing the op- claim 29 wherein said indexing means includes a eration of the thermographic print head when the 100 plurality of home position indices and wherein said voltage drops below a predetermined level. position indices are interposed between said home 28. A hand held labeling machine as recited in position indices.

claim 27further including memory means coupled to 36. A hand-held labeling machine as recited in said processing means, wherein said processing claim 35 wherein said indexing means includes means and said memory means cooperate to trans- 105 areas having a predetermined width separating said fer data therebetween, wherein said voltage moni- position indices from each other, said discfurther in toring means is operative to preveritthe transfer of cluding an area having a width greaterthan said pre data between said processing means and said determined width separating said position indices memory means when the voltage drops belowthe from one of said home position indices.

predetermined level. 110 37. A hand-held labeling machine comprising; a 29. A hand-held labeling machine comprising; a housing having a manually engageable handle,the housing having a manually engageable handle,the housing having meansfor holding a label supply roll housing having meansfor holding a label supply roll of a composite web having labels releasably adhered of a composite web having labels releasably adhered to a backing strip, means for printing on a label ata to a backing strip, means for printing on a label at a 115 printing position, means for peeling the printed label printing position, means for peeling the printed label from the backing strip, label applying means dis from the backing strip, label applying means dis- posed adjaceritthe peeling means, meansforadvan posed adjaceritthe peeling means, meansforadvan- cing thewebto peel a printed label fromthe backing cing thewebto peel a printed label fromthe backing strip atthe peeling means and advancethe printed strip atthe peeling means and advancethe printed 120 label into label applying relationship with the label label into label applying relationship with the label applying means and to advance another label into applying means and to advance another label into the printing position, means for entering selected the printing position, means for entering selected data to be printed, the printing means including a data to be printed, said advancing means having a thermographic print head having a plurality of indi predetermined amount of backlash, the printing 125 vidually selectable print elements for printing on a means including a thermographic print head having thermographic label at a printing position, means a plurality of individually selectable print elements coupled to said data entering meansfor electrically for printing on a thermographic label at a printing processing the selected data and energizing the indi position, means coupled to said data entering means vidual print elements in a predetermined sequence for electrically processing the selected data and en- 130 determined by the selected data to print data on the 11 GB 2 186 405 A 1 label, said advancing means including an electric processing the selected data and energizing the indi motor and meansfor controlling the speed of the el- vidual print elements in a predetermined sequence ectric motor, said speed control means including: determined bythe selected data to print data on the meansfor providing an energizing pulseto said el- label,wherein said advancing means includes inde- ectric motor; 70xing means coupled to said processing meansfor meansfor providing a predetermined time delay providing signals representative of the position of a following the termination of the energizing pulse; label to said processing means, said indexing means means responsive to the delay means forsampl- including a circular member having three home posi ing the amplitude of the back EMF generated bythe tion indices and a plurality of position indices inter electric motor after a predetermined delayfollowing 75 posed between said home position indices, said cir the termination of the energizing pulse; cular member being adapted to be driven by a shaft, means for comparing the amplitude of the sam- said indexing means including meansforfixedly pled backEMFwith a predetermined amplitude; and attaching said circular memberto said shaftwhile means responsiveto said comparing meansfor providing an angular adjustment between said cir generating another energizing pulse within a second 80 cular member and said shaft, said adjusting means predetermined time interval if the amplitude of this including keying means disposed on said shaft and back EM F is belowthe predetermined amplitude. first, second and third engaging means disposed on 38. A hand-held label ing machine as recited in said circular member for engaging said keying claim 37 further including means responsive to said means, said keying means and said engaging means comparing means for preventing the generation of 85 cooperating to prevent rotation of said circular another energizing pulse within thesecond pred- member relativeto said shakwherein said first en etermined time interval if the amplitude of the back gaging means is disposed 12T+ 2N'from said EMF is abovethe predetermined amplitude. second engaging means, said third engaging means 39. A hand-held label ing machine as recited in being spaced from said second and first engaging claim 38 wherein said comparing means includes an 90 means by 12T- Wto permit a -NO adjustmentof analog comparator. said circular member relativeto said shaft.

40. A hand-held labeling machine as recited in 43. A hand-held labeling machine as recited in claim 39wherein said comparing means responsive claim 42,wherein N is equal to approximately 10.

means includes a digital sampling means responsive 44. A hand-held labeling machine is recited in to said delay means. 95 claim 42, wherein N is equal to approximately T.

41. A method for controlling the operation of a 45. A hand-held labeling machine as recited in thermographic printing head of the type having a claim 42, wherein said indices are disposed on a disc.

plurality of individually energizable, densely spaced, 46. A hand-held labeling machine as recited in printing elements disposed in an array, said el- claim 45, wherein said indices are light contrasting ements each having a predetermined length, com- 100 indices.

prising the steps of: 47. A hand-held labeling machine as recited in advancing a web of label-containing sheet stock claim 46, wherein said indices are formed by aper past said print heads; tu res formed in said disc.

providing an index representative of the beginning 48. A hand-held labeling machine as recited in of a label; 105 claim 47,wherein the apertureforming said home providing at least one index adjacentto said label position index is largerthan the apertures forming beginning index representative of a printing area on said position indices.

the label; 49. A hand-held labeling machine as recited in detecting said indices; and claim 48, wherein said disc includes a plurality of operating predetermined ones of said printel- 110 home position indices and wherein said position in ements in orderto print predetermined patterns on dices are interposed between said home position in said web upon detection of said printing area index. dices.

42. A hand-held labeling machine comprising; a 50. A hand-held labeling machine as recited in housing having a manually engageable handle, the claim 49, wherein said disc includes areas having a housing having means for holding a label supply roll 115 predetermined width separating said position in of a composite web having labels releasably adhered dices from each other, said discfurther including an to a backing strip, means for printing on a label at a area having a width greater than said predetermined printing position, means for peeling the printed label width separating said position indices from one of from the backing strip, label applying means dis- said home position indices.

posed adjacentthe peeling means, meansfor advan- 120 51. A hand-held labeling machine as recited in cing the web to peel a printed label from the backing claim 42, wherein said home position index is larger strip atthe peeling means and advance the printed than said position indices.

label into label applying relationship with the label 52. A hand-held labeling machine as recited in applying means and to advance another label into claim 51,wherein said indexing means includes the printing position, meansfor entering selected 125 areas having a predetermined width separating said data to be printed,the printing means including a position indicesfrom each other, said indexing thermographic print head having a plurality of indi- meansfurther including an area having a width grea vidually selectable print elementsfor printing on a terthan said predetermined width separating said thermographic label at a printing position, means position indices from one of said home position in coupled to said data entering means for electrically 130 dices.

12 GB 2 186 405 A 12 53. A hand-held labeling machine comprising; a 60. A hand-held labeling machine as recited in housing having a manually engageable handle, the claim 59 wherein said disc includes a plurality of housing having means for holding a label supply roll home position indices and wherein said position in of a composite web having labels releasably adhered dices are interposed between said home position in to a backing strip, means for printing on a label at a 70 dices.

printing position, means for peeling the printed label 61. A hand-held labeling machine as recited in from the backing strip, label applying means dis- claim 60 wherein said disc includes areas having a posed adjacentthe peeling means, means for advan- predetermined width separating said position in cing the web to peel a printed label from the backing dices from each other, said discfurther including an strip atthe peeling means and advance the printed 75 area having a width greaterthan said predetermined label into label applying relationship with the label width separating said position indices from one of applying means and to advance another label into said home position indices.

the printing position, means for entering selected 62. A hand-held labeling machine as recited in data to be printed, the printing means including a claim 53 wherein said home position index is larger thermographic print head having a plurality of indi- 80 than said position indices.

vidually selectable print elements for printing on a 63. A hand-held labeling machine as recited in thermographic label ata printing position, means claim 62 wherein said indexing means includes coupled to said data entering means for electrically areas having a predetermined with separating said processing the selected data and energizing the indiposition indicesfrom each other,said indexing vidual print elements in a predetermined sequence 85 means further including an area having a width grea determined bythe selected data to print data on the terthan said predetermined width separating said label,wherein said advancing means includes inde- position indicesfrom one of said home position in xing means coupledto said processing meansfor dices.

providing signals representative of the position of a 64. A position indicating device comprising:

label to said processing means, said indexing means 90 a circular member having a plurality of indices dis including a circular member having at leasttwo posed thereon and adapted to be driven by a shaft; home position indices and a plurality of position in- meansforfixedly attaching said circular member dices interposed between said home position in- to said shaftwhile providing an angular adjustment dices, said circular member being adapted to be between said circular member and said shaft, said driven by a shaft, said indexing means including 95 adjusting means including keying means disposed means forfixediy attaching said circular memberto on said shaft and first, second and third keying said shaftwhile providing an angular adjustment be- means engaging means disposed on said circular tween said circular member and said shaft, said adju- member, said keying means and said engaging sting means including keying means disposed on means cooperating to prevent rotation of said cir said shaftand a plurality of engaging means dis- 100 cular member relative to said shaft, wherein said first posed on said circular memberfor engaging said engaging means is disposed 120' + Mfrom said keying means, said keying means and said engaging second engaging means, said third engaging means means cooperating to prevent rotation of said cir- being spaced from first and second engaging means cular member relativeto said shaft, wherein adjacent by UT- Wto permit a Wadjustment of said cir ones of said engaging means are unevenly spaced 105 cular member relative to said shaft.

from each other by a predetermined spacing to 65. A position indicating device as recited in permit an adjustment of said circular member relatclaim 64wherein N is equal to V.

iveto said shaft, the spacing between said engaging 66. A position indicating device as recited in means being substantially less than the adjustment claim 64wherein N is equal to T.

of the circular member relative to said shaft. 110 67. A position indicating device as recited in 54. A hand-held labeling machine as recited in claim 64wherein said circular member is a disc.

claim 53, wherein said plurality of engaging means is 68. A position indicating device further including three and said predetermined spacing is 122', 119' a plurality of position indices disposed on said cir and 11Tto provide an adjustment of -tl'. cular member between said indices.

55. A hand-held labeling machine as recited in 115 69. A hand-held labeler substantially as herein claim 53, wherein said plurality& engaging means is described with reference to and as shown in the three and said predetermined spacing is 124% 118' drawings.

and 11 Wto provide an adjustment of T.

56. A hand-held labeling machine as recited in Amendments to the claims have been filed, and have claim 53, wherein said indices are disposed on a disc. 120 the following effect:

57. A hand-held labeling machine as recited in (a) Claims 1-69 above have been deleted ortextu claim 56 wherein said indices are light contrasting allyamended.

indices. (b) New or textually amended claims have been 58. A hand-held labeling machine as recited in filed asfollows:

claim 57 wherein said indices areformed byaper- 125 tures formed in said disc. 1. A hand-held labeling machine comprising: a 59. A hand-held labeling machine as recited in housing having a manually engageable handle, the claim 58 wherein the aperture forming said home housing having means for holding a label supply roll position index is larger than the apertures forming of a composite web having labels releasably adhered said position indices. 130 to a backing strip, means for printing on a label at a 13 GB 2 186 405 A 13 printing position, means for peeling the printed label 8. Atiming disc as recited in claim 7, wherein from the backing strip, label applying means dis- said predetermined width is equal to the width of the posed adjacent the peeling means, meansfor advan- positioning apertures, and wherein the width of said cing the webto peel a printed label from the backing extended width area is approximately twice said pre- strip atthe peeling means and advance the printed 70 determined width.

label into label applying relationship with the label 9. A timing disc as recited in claim 8, wherein the applying means and to advance another label into width of said home position apertures is greaterthan the printing position, means for entering selected the width of said extended width area.

data to be printed, the printing means including a 10. A system for controlling the advancement of thermographic print head having a plurality of indi- 75 a web of sheet stock containing a plurality of labels vidually selectable print elements for printing on a disposed along the longitudinal dimension of said thermographic label at a printing position, means web, comprising:

coupled to said data entering means for electrically meansfor printing on a label at a printing position:

processing the selected data and energizing the indi- means for advancing the web past the printing vidual print elements in a predetermined sequence 80 position:

determined bythe selected data to print data on the means for entering selected data to be printed:

label, further including indexing means operable by means coupled to said data entering means for el said advancifig means and coupled to said proectrically processing the selected data and energiz cessing means forproviding signals representative ing the printing means to printthe selected data on of the position of a label relative to said printing posi- 85 the label: and tion, said indexing means including a plurality of indexing means electrically coupled to said pro home position indices and a plurality of position in- cessing meansfor providing signalsthereto repre dices disposed adjacent each home position index, sentative of the position of a label relative to said said indices being disposed on a disc as light contra- printing position, said indexing means including a sting indicesformed by aperture on said disc, said 90 rotary indexing device having at leastone home pos home position index being largerthan said position ition index disposed thereon, a plurality of position indices. ing indices disposed adjacentto said home position 2. A hand-held label ing machine as recited in index and a warning track disposed adjacent said claim 1 wherein said disc includes areas having a plurality of positioning indices, sensing means dis predetermined width separating said position in- 95 posed in proximityto said indexing deviceforsen dicesfrom each other, said discfurther including an sing the indices and thewarning track, said indexing area having a width greaterthan said predetermined device being mechanically coupled to said advan width separating said position indicesfrom one of cing meansto sequentially advancethe home posi said home position indices. tion index,the positioning indices and thewarning 3. A hand-held labeling machine as recited in 100 track past the sensing means, said processing means claim 2 wherein said disc is fabricated from electro- being responsive to said positioning indices to cause deposited nickel. the printing meansto printthe selected data at pred 4. A hand-held label ing machine as recited in etermined locations on the web, and said processing claim 1, wherein said indexing means includes a means being further responsive to said warning plurality of home position indices and wherein said 105 trackfor causing the advancing means to terminate position indices are interposed between said home the feeding of said web in such a mannerthat a home position indices. position index is in alignmentwith the sensing 5. A hand-held label i ng machine as recited in means after the feeding of the web has terminated.

claim 4, wherein said indexing means includes areas 11. A system as recited in claim 10, wherein said having a predetermined width separating said posi- 110 advancing means includes an electric motor and tion indices form each other, said indexing means wherein said processing means is operative to cause further including an area having a width greaterthan dynamic braking to be applied to said electric motor said predetermined width separating said position when a warning track is sensed.

indices from one of said home position indices. 12. Asystem as recited in claim 10or 1 1,wherein 6. A timing discfor providing signals represent115 said rotary indexing device includes a plurality of ative of the position of a shaft comprising: home position indices and wherein a plurality of pos a disc having a plurality of home position aper- itioning indices and one warning track are inter tures having a predetermined width formed about posed between adjacent home position indices.

the periphery thereof, said disc further including a 13. A system as recited in claim 12, wherein said plurality of positioning apertures interposed be- 120 rotary indexing device includes a disc having said in tween said home position apertures, said position- dices and warning tracks disposed thereon.

ing apertures having a width that is narrowerthan 14. A system as recited in claim 13, wherein said the width of said home position apertures. indices are light contrasting indices.

7. A timing disc as recited in claim 6, wherein 15. A system as recited in claim 14, wherein said said positioning apertures are separated from each 125 indices are formed by apertures formed in said disc.

other by a plurality of areas having a predetermined 16. A system as recited in claim 15, wherein the width, and wherein said disc includes an extended aperture forming said home position index is larger width area having a width greaterthan said pred- than the apertures forming said position indices.

etermined width separating said positioning aper- 17. A system as recited in claim 16, wherein said tures from one of said home position apertures. 130 positioning indices are separated by areas of said 14 GB 2 186 405 A 14 disc having a predetermined width and wherein said claim 26, wherein said disc includes areas having a warning track is formed by an area of said disc that is predetermined width separating said position in widerthan the areas separating said positioning in- dices from each other, said disefurther including an dices. area having a width greaterthan said predetermined 18. A system as recited in claim 17, wherein said 70 width separating said position indices from one of wider area is approximately twice as wide as one of said home position indices.

the areas separating said positioning indices. 28. A hand-held labeling machine as recited in 19. A system as recited in claim 16, wherein the claim 22, wherein said indexing means includes a aperture forming said home position index is suffici- plurality of home position indices and wherein said entlywide that at least a portion of said aperture reposition indices are interposed between said home mains in alignmentwith said sensing means despite position indices.

backlash of said web. 29. A hand-held labeling machine as recited in 20. Asystern as recited in any of claims 10to 19, claim 28, wherein said indexing means includes wherein said home position index is sufficiently wide areas having a predetermined width separating said that at least a portion of the home position index re- 80 position indices from each other, said discfurther in mains in alignmentwith said sensing means despite cluding an area having a width greaterthan said pre backlash of said web. determined width separating said position indices 21. A hand-held labeller comprising a system as from one of said home position indices.

recited in anyof claims 10to20. 30. A hand-held labeller substantially as herein 22. A hand-held labeling machine comprising a 85 described with reference to and as shown in the housing having a manually engageable handle, the drawings.

housing having means for holding a label supply roll of a composite web having labels releasably adhered to a backing strip, means for printing on a label at a printing position, means for peeling the printed label Printed for Her Majesty's Stationery Office by Croydon Printing Company (UK) Ltd, 6187, D8991685.

from the backing strip, label applying means dis- Published by The Patent Office, 25 Southampton Buildings, London,WC2A lAY, posed adjaceritthe peeling means, meansfor advan- from which copies may be obtained.

cing the web to peel a printed label from the backing strip atthe peeling means and advance the printed label into label applying relationship with the label applying means and to advance another label into the printing position, means for entering selected data to be printed, said advancing means having a predetermined amount of backlash, the printing means including a thermographic print head having a plurality of individually selectable print elements for printing on a thermographic label at a printing position, means coupled to said data entering means for electrically processing the selected data and en ergizing the individual print elements in a pred etermined sequence determined bythe selected data to print data on the label, wherein said advancing means includes indexing means having a home pos ition index and a plurality of position indices, and meansfor detecting said indices, said indices being selectively alignable with said detecting means, said home position index being largerthan said position indices and having a predetermined size selected so that at least a portion of said home position index remains aligned with said detecting means upon the backlash of said advancing means.

23. A hand-held iabeling machine as recited in claim 22, wherein said indices are disposed on a disc.

24. A hand-held labeiing machine as recited in claim 22, wherein said indices are light contrasting indices.

25. A hand-held labeling machine as recited in claim 24, wherein said indices are formed by aper tures formed in said disc.

26. A hand-held labeling machine as recited in claim 25, wherein said disc includes a plurality of home position indices and wherein said position in dices are interposed between said home position in dices.

27. A hand-held labeling machine as recited in