Abstract:
A cutting mechanism having a movable carriage and two cutters. Each cutter has an anvil that opposes a blade, and one of these is a roller that rolls against the other for progressively biasing material against the blades, producing cuts through the material. The rollers are rotatably mounted to the carriage, which is mounted to a lead screw that controls the position of the carriage. As the carriage moves across the material, the rollers roll, and the material is cut. The space between the anvil and the blade of at least one of the cutters can be varied to disengage that cutter so that the rolling of the roller will not cut the material. The engagement and disengagement of the cutter is dependent on the position of the carriage.

Description:
This is a division of application Ser. No. 08/855,417, filed May 13, 1997 U.S. Pat No. 6,014,921. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a cutting mechanism for making two cuts through a material. More particularly, it relates to a printing device having anvils that roll against blades to produce cuts of different depths through a tape. 
     BACKGROUND OF THE INVENTION 
     Electronic printing apparatus are known which use a supply of multi-layer tape, housed in a cassette received by the printing apparatus. The multi-layer tape comprises an image receiving layer and a backing layer secured to one another via an adhesive layer. After an image has been printed onto the image receiving layer, the backing layer can be removed allowing the receiving layer to be secured to an object using the adhesive layer. Such printing apparatus include cutting mechanisms for cutting off a portion of the tape for its use as a label after an image has been printed onto the image receiving layer. For this purpose, the cutting mechanism includes a blade for cutting through all of the layers of the multi-layer tape. In some printing apparatus, the cutting mechanism also includes a tab cut blade for cutting through only one of the layers of the multi-layer tape, either the image receiving layer or the backing layer, leaving the other layer intact. For example, in a machine made and sold by Esselte under the trade mark DYMO 6000, a tab cut blade is provided which cuts through the top image receiving layer while leaving the backing layer intact. Such a tab cut allows easy separation of the image receiving layer from the backing layer. 
     In the DYMO 6000, the tab cut blade is a ceramic blade which is set via insert molding in a tab cut blade holder to a protrusion of about 100 microns. When a tab cut is to be made, force is applied to the blade holder to cause the blade to cut through the image receiving layer of the tape while the tape is supported by a flat anvil surface. Precise control of the amount of blade protruding from the blade holder ensures that a reliable tab cut is made which always cuts through the image receiving layer without cutting the backing layer. 
     One problem with this arrangement is that it requires the application of significant force, particularly when cutting wide tapes. These printing apparatus operate with tapes having widths of 6 mm, 12 mm and 19 mm. When performing a tab cut on a 19 mm tape, the force required can be as much as 80 to 100 N. It is very difficult for smaller printing apparatus to apply the high loads that the cutting operation requires. 
     A cutting mechanism which overcomes this difficulty is described in our copending U.S. application Ser. No. 08/556,885. In the disclosed cutting mechanism, an anvil is mounted for rolling motion relative to a cutting blade. To perform a cut, the anvil is rolled along the blade, progressively cutting across the tape. Thus, the actuation force required in this operation is much lower than if the entire width of tape were to be cut simultaneously. 
     In the &#39;885 application, in which the rolling anvil is used to implement a tab cut, a full cut is implemented by a separate cutting mechanism, mechanically connected to the rolling anvil. This separate mechanism forces the entire cutting edge of a blade against a stationary anvil at once, and hence requires a large force to be applied during the cut. 
     As described in U.S. Pat. No. 5,458,423, a mechanism that produces a full cut can be disabled so that only a tab cutting mechanism operates. This allows a string of labels to be produced, wherein the labels are secured to a common backing strip and separated by tab cuts. The disabling of the full cutting mechanism in this reference, however, must be done manually. From a practical point of view, this means that the machine must be located accessibly to a user. 
     It is desirable to provide for remote printing devices which can operate by communication with host PCs or other desktop label formulation apparatus. Such printing and cutting devices can be controlled remotely from the printing apparatus itself. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a cutting mechanism for cutting a material, such as a multilayer tape. The mechanism has first and second cutters respectively with first and second opposing blade and anvil components. Either the first anvil or blade component and either the second anvil or blade component are rollers that are mounted for rolling along the anvil or blade component opposed to each roller. This rolling motion progressively biases and cuts the material with the first blade component. Likewise, one of the second anvil and blade components is in the form of a second roller mounted for rolling along the other for progressively biasing and cutting the tape with the second blade component. Preferably, the first blade and anvil components are arranged to cooperatively cut through all layers and the entire thickness of the multi-layer tapes and the second blade and anvil components are arranged to cooperatively cut through one or more layers of the multi-layer tape, while leaving at least one layer and a portion of the thickness of the tape intact. 
     The rollers are preferably the anvil components, and are rotatably mounted on a carriage that is movable parallel to the blades. As the carriage moves, the anvil components roll over the blades, widthwise with respect to the tape, thus cutting the tape. 
     The resulting cutting -mechanism can make a tab cut and a full cut through a multi-layer tape at locations spaced along the length of the tape. The cutting mechanism is particularly useful in printing devices of the type hereinbefore described. 
     The present invention can also provides a printing device with the described cutting mechanism. This printing device can be operated from an input device such as a keyboard, in which a user may enter information such as characters to be printed, length of label, and format of label, and may select other modes for the printer to operate. 
     The printing device preferably also includes a printing mechanism comprising a printhead and platen for performing printing operations. 
     In one type of suitable printing device, an multilayer image-receiving tape is passed in overlap with a thermal transfer ribbon through the printing mechanism. The tape is fed through the printing location by a motor arranged to drive the platen or a set of feed rollers to pull the tape past the printing location. The printing device preferably has a controller in the form of a microprocessor which controls the timing and positioning of printing with respect to the movement of the tape, according to the data entered by the user. The thermal printhead has a column of printing elements so that an image is printed on the tape column by column as the tape moves past the printing mechanism. 
     In normal operations, the tape is printed upon, and tab and full cuts are made to produce a label. Alternatively, tab cuts can be made at spaced locations along the length of the tape to produce numerous labels which can then be removed from a common backing. To achieve this, one of the cutters is selectively disengageable, for example by increasing the spacing between an opposing blade and anvil, so that the cutter will not produce a cut in its disengaged state. Preferably, this cutter can be engaged and disengaged by moving the rolling anvils passed predetermined positions. 
     Preferably, each anvil component has a circumferential slot aligned with its opposing blade component to prevent direct contact between the blade component and the surface of the anvil component. This arrangement reduces damage and wear of the cutters. The amount by which each blade component protrudes from a blade holder can be less accurately controlled than when used with an anvil component that lacks the slot. This relaxes the tolerances on production blade straightness. With these slots, a common blade holder can be used to hold two blade components protruding therefrom by different amounts, one protruding sufficiently to produce a tab cut, and the other to produce a full cut through the thickness of the tape. 
     The input device, or other user interface, does not need to form part of a common housing with the printing mechanism and cutting mechanism, but may be disposed remotely therefrom. A remote arrangement allows the user to control the cutting mechanism, without the needing to intervene manually. 
     The invention also provides a lead screw with a cam on its end. The lead screw is received through an internally threaded bore in the carriage. A switch, resiliently biased against the cam produces electrical pulses, and a counter of the controller measures the position of the carriage. 
     This invention enables a user to implement a variety of label options, such as printing multiple copies of labels, wherein copies can be counted more simply than with earlier printing devices. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Reference will now be made by way of example to the accompanying drawings in which: 
     FIG. 1 is a plan view of a cutting mechanism in a printing device with a cassette; 
     FIG. 2 is a section taken along lines II—II of FIG. 1, showing the rolling anvil in a start position; 
     FIG. 3 is a sketch of components of a cutting mechanism according to the present invention; 
     FIGS. 4A and 4B are a side view and plan view of a cassette layout in an embodiment of the invention; 
     FIG. 5A is a view of the cutting mechanism of FIG. 3; 
     FIG. 5B is a section through a carriage shown in FIG. 5A; 
     FIG. 5C illustrates the carriage of FIGS. 5A and 5B in its molded form; 
     FIG. 6 illustrates a preferred embodiment of the invention in which a full cut blade is selectively disengageable; 
     FIGS. 7A-C are end views of the cutting mechanism of FIG. 6; 
     FIG. 8 is a sketch showing different stop positions of an anvil holder according to the invention; 
     FIG. 9 is a diagram showing drive and sensing components of the cutting mechanism of FIG. 6; 
     FIG. 10 is a diagram showing signals from the sensing components of FIG. 9; 
     FIG. 11 is a block diagram of control circuitry of the preferred embodiment; 
     FIG. 12 is a flow chart of a selective cutting operation; 
     FIG. 13 is a flow chart showing operation in a preferred strip label mode; 
     FIG. 14 is a flow chart illustrating a process of selection of cutting options by a user; 
     FIG. 15 shows a printer display, according to the invention, displaying options in a special mode; and 
     FIG. 16 is a display showing options in a set up mode. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1 and 2 are views of a cutting mechanism as described in U.S. patent application Ser. No. 08/556,885 shown in a printing apparatus that has a printing mechanism and in which a cassette is located. The content of that application is expressly incorporated herein by reference thereto to the extent needed for a complete understanding of the invention. Reference numeral  2  designates a casing of the printing apparatus defining a cassette receiving bay. Within the casing  2  is located a base plate  4  which includes an upstanding part  6  used for mounting a return spring  8 . The printing mechanism includes a printhead  10  and a platen  12  which cooperates with the printhead  10  to effect printing on an image receiving tape T. The printhead  10  and platen  12  are mounted within the casing  2  on the base plate  4 . The printhead  10  is movable from the operative position as shown in FIG. 1 to an inoperative position in which it is spaced from the platen  12  to allow easy removal and insertion of a cassette. Reference numeral  14  denotes a cassette located in the cassette receiving bay. The cassette  14  holds a supply of ink ribbon and image receiving tape which extend in overlap between the platen and printhead  10 . The ink ribbon is then wound back within the cassette  14  and the image receiving tape extends out of the printer. Reference numeral  16  denotes the printing zone where the image receiving tape and ink ribbon extend in overlap, and reference numeral  18  denotes the zone where the tape exits from the printer. Between zones  16  and  18  is an area in which cutting takes place as described below. 
     The cutting mechanism has two main parts. The first part is a cutter body  20  on which is mounted a full-cut blade  22 . The blade  22  is configured to cut through the full thickness of the tape T as it moves towards a slot  24  in the cassette  14 , at a first cutting location C 1 . The cutter body  20  moves on supports  56 , 58 , and includes at its surface, a tape clamp  28  for holding the tape T against a supporting surface of the cassette  14  during cutting. Reference numeral  26  denotes a tape clamping spring of which there are two, one associated with each support  56 , 58 . Operation of this part of the cutting mechanism is disclosed in our European Patent Application Publication No. 0634275, the content of which is expressly incorporated herein by reference thereto. 
     The second part of the cutting mechanism makes a tab cut through the tape at a second cutting location C 2 , spaced from the fixed cutting location C 1 . The tape T is preferably a multi-layer tape including an upper layer, an adhesive layer and a backing layer which can be removed from the adhesive layer so that the adhesive layer may be secured to an object using the adhesive layer. An image or message is printed on the upper layer of the tape. In FIG. 1, the upper layer of the tape is to the right of the drawing, adjacent the printhead  10 . 
     The second part of the cutting mechanism includes a blade holder  30  which holds a tab cut blade  32 . A tab cut blade holder  30  is mounted in a tab cut sprung body  34  which itself is sprung against a tab cut support part  36  of the printer. This part of the cutting mechanism also includes a rolling anvil  38 . The rolling anvil  38  is rolled down against the tab cut blade  32  causing a cut to be made progressively across the width of the tape T. The depth of cut is controlled so that the cut is made only through the upper layer of the tape, leaving the backing layer intact. 
     The rolling anvil  38  has an arcuate anvil surface  3  and an actuating part  38   a . FIG. 1 and 2 show the rolling anvil  38  in the start position. Two guides control the locus of the anvil  38 . A first guide  40  is located towards the casing  2  of the printer, and a second guide  42  is located inwardly towards the cassette receiving bay. The guides  40 , 42  include guide tracks, and the anvil has two protrusions, such as balls or pins disposed near the ends of its arcuate anvil surface  3 . The protrusions ride and are guided within the tracks. The pins cannot be seen in FIG. 2 because they are on the side of the rolling anvil away from the viewer. The pins located on the side of the anvil facing the viewer have been omitted from FIG. 2 for the sake of clarity. It will be appreciated that it is not necessary in all circumstances to positively guide the anvil from both sides. Guidance by a single guide on one side is sufficient in many applications. 
     The rolling anvil  38  also carries a cutter body actuation pin  48 . This pin is disposed on the side of the anvil  38  that faces away from the viewer in FIG.  2 . The cutter body  20  defines a track  50  in which pin  48  travels. The track  50  extends at an angle to the tape T. 
     Operation of this earlier cutting mechanism will now be described. FIG. 2 illustrates a start position. In this position, the return spring  8 , which extends between upstanding part  6 , around pulley  57 , and terminates at the cutter body actuation pin  48 , is in a relaxed state. The guide pins are located in an upper portion of the guide track. The cutter body  20  is in a position holding the blade  22  spaced from the tape T. To make a cut, the actuation part  38   a  of the rolling anvil  38  is moved in the direction of arrow A. When the anvil  38  is moved, the arcuate anvil surface  3  rolls along the surface of the tab cut blade holder and progressively tab cuts the tape at the second cutting location C 2 . The guide pins and guide track are arranged to ensure that anvil  38  repeatably rolls over the blade holder  38 . 
     As the rolling anvil  38  moves, the cutter body actuation pin  48  is caused to move along the track  50  in the cutter body  20 . This forces cutter body  20  towards the tape T. 
     Downward movement of the cutter body actuation pin  48  also extends and tenses return spring  8 . As the cutter body  20  moves right in FIG. 2, the full cut blade  22 , supported by the cutter body  20 , makes a full cut through the tape T at the cutting location Cl. 
     FIGS. 3-5 show an embodiment of a cutting mechanism according to the present invention which does not require a cassette to have a slot in a support wall. In this embodiment, the location of the cutting mechanism independent of the placement of the cassette. Moreover, the cassette need not contain both image receiving tape T and thermal transfer tape. The thermal transfer tape may be contained in a separate cassette or dispensed with altogether. 
     Referring to FIG. 4B, a baseplate of the printing mechanism has been omitted for the sake of clarity, although a cassettes is preferably received in a cassette receiving bay. The printing device has a printing mechanism comprising a printhead  210  and a platen  212 , similar to those described above. An ink ribbon cassette  214  houses a supply of ink ribbon or thermal transfer ribbon, and a substrate cassette  216  houses a supply of image receiving tape T. The image receiving tape T and the ink ribbon are passed in overlap through a print zone, between the printhead  210  and the platen  212 , for printing. The ink ribbon is then fed back into the ink ribbon cassette  214 , while the image receiving tape T with a printed image thereon is fed from the print zone towards the left in FIG.  4 B. Rotation of the platen  212  moves the tapes. 
     The substrate cassette  216  has a guide part  218  at an exit location EL that guides the tape T. Downstream of the exit location EL is a cutting mechanism  220 . FIG. 4A is a view taken from the side of FIG. 4B in the direction of arrow IV. The baseplate  222  of the printing mechanism is seen supporting the ink ribbon cassette  214  and the substrate cassette  216 . Tape T is shown exiting the printer in the direction of arrow B in FIG. 4A, and towards the viewer in FIG.  4 A. 
     Referring to FIG. 3, the cutting mechanism  220  has a blade holder  100  which is located at a first cutting location C 1  and has a full cut blade  102  for cutting through all layers of multi-layer tape T; and a tab cut blade  103 , located at cutting location C 2 , for cutting through only one or more layers of a multi-layer tape, without cutting the backing layer. The cutting mechanism also includes an anvil holder  104  which carries two rolling anvils  106  and  108 , as shown in FIG. 3, that are respectively opposed to each blade  102  and  103 . 
     The first rolling anvil  106  cooperates with the full cut blade  102  as a first cutter, and the second of these  108  cooperates with the tab cut blade  103  as a second cutter. The anvil holder  104  is preferably a central shaft that is rotatable about its axis A—A. Each of the rolling anvils has a narrow circumferential slot  106   a  and  108   a  respectively. Each slot  106   a  and  108   a  is aligned with its opposing blade  102  and  103  to remove direct contact between the blades  102  and  103  and the anvils  106  and  108 . The cutting locations C 1  and C 2  are spaced apart similarly as in FIG. 1 to provide a full cut at cutting location C 1  and a tab cut at cutting location C 2 . 
     FIGS. 5A-C are views taken from the end of the cutting mechanism  220 , facing the same direction as FIG.  4 A. In FIG. 5A, blade holder  100  is seen sectioned with the full cut blade  102  showing. The width of the tape is denoted W. The anvil holder  104  is mounted on a carriage  110  and is held under constant bias towards blade  102 , against the blade holder  100 , by spring  112 . This downwards force produced by spring  112  is denoted by arrow F. The carriage is movable back and forth widthwise of the tape T under the action of a motor driven lead screw  114 . As the carriage is driven by the lead screw  114 , the rolling anvils  106  and  108  rotate causing, biasing tape T against blades  102  and  103 . 
     FIG. 5B is a section through the carriage  110 , showing its operation in more detail. The lead screw  114  extends through an aperture or bore  115  in the carriage  110  and is received by threaded nuts  117  at each end of the bore. Rotation of the lead screw  114  moves the carriage  110  widthwise over the tape. 
     The carriage  110  consists of a main body portion  110   a  and a hinged portion  110   b . The hinged portion  110   b  has a recess  119  for receiving the holder  104  of the rolling anvils  106  and  108 . The hinged portion  110   b  is hinged relative to the body portion  110   a  at hinge  110   c . The spring  112  biases the body portion  110   a  away from the hinged portion  110   b , applying the downwards force F explained above with reference to FIG.  5 A. 
     For ease of manufacture, the carriage  110  is manufactured as an integral unit in which the hinged portion  110   b  is open relative to the body portion  110   a . This is shown in more detail in FIG.  5 C. By manufacturing the carriage in this manner, the spring  112  can be mounted onto the carriage  110 , and the hinged portion  110   b  may be folded back in the direction of arrow Y, simplifying assembly. 
     Referring to FIG. 6, in a preferred embodiment of the invention, the full cut blade  102  can be selectively engaged or disengaged to allow the cutting mechanism either to perform a full cut with a tab cut, or a tab cut only. FIG. 6 is a view similar to FIG.  3  and shows the rolling anvils  106  and  108  on the anvil holder  104 . 
     The full cut blade  102  is mounted on cam-engagement portion such as a pin  116  which is actuated by a key  118 . The key  118  is has an elongate part which runs in a guide groove  120  formed in the blade holder  100 . In FIG. 7A, the key  118  is shown in its retracted position. The key  118  has first and second cam surfaces  122  and  123  that are engageable with pin  116 . The key  118  also has an actuating part  124  that extends upwardly from the elongate part of the key  118 . The actuating part  124  carries an actuator  126  which extends lengthwise of the blade holder  100 , in the direction of movement of the carriage  110 . 
     FIG. 7A shows the anvil holder  104  in its “home” position, at the extreme left hand side of its travel. In this position, the carriage  110  holds the actuating part  124  of the key  118  so that the second cam surface  123  holds pin  116  downwards, disengaging the full cut blade  102 . As the anvil holder  104  rolls from the home position to the right hand side of FIG. 7A in the direction of arrow C, only a tab cut is produced on the tape T. 
     The anvil holder  104  has two stop positions, an inner stop position shown in FIG.  7 B and an outer stop position shown in FIG.  7 C. At the inner stop position, the anvil holder  104  abuts a first end  128  of the actuator  126 , but engages it no further and causes no movement of the key  118 . Therefore, the full cut blade  102  remains in its disengaged position. Hence, when the anvil holder  114  returns from the inner stop position to its home position, no full cut of the label is made. 
     However, if the anvil holder  104  rolls to the outer stop position shown in FIG. 7C, it will readily be understood that it has now engaged the first end  128  of the actuating component  126 , pulling key  118  to the right in the drawing. The second cam surface  123  of the key  118  releases the pin  116 . The full cut blade  102  is returned to its cutting position, preferably as the first cam surface  122  engages pin  116 . On the return stroke of the anvil holder  104 , as it moves towards its home position, a full cut is produced through the tape. 
     Once a full cut is made, the anvil holder  104  shifts the actuating component  124  of the key  118 , which coincides with a second end of the actuator  126 , back towards the left as the holder  104  reaches its home position. The second cam surface of key  118  thus moves pin  116  down, also moving the full cut blade  102  to its disengaged position. Consequently, the cutting mechanism will not make a full cut through the tape T in the next outbound stroke of the anvil holder  104 . In this embodiment, full cuts are only performed during the return stroke of the anvil holder  104 . 
     FIG. 8 shows the home position, inner stop position, and outer stop position with reference to the width of the tape T. This arrangement thus allows a user to select whether or not both a full cut and a tab cut are to be made, or a tab cut only. This can be done automatically using the arrangement shown in FIG.  9 . 
     FIG. 9 does not show the blade holder but shows the carriage  110  with the rolling anvil  106 . As described above with reference to FIG. 5A, the carriage  110  is driven on a lead screw  114 . Reference numeral  200  denotes a d.c. motor which is used to drive the lead screw  114  through a gear reduction pair  202 . A first leaf switch  204  is provided to detect the home position of the anvil holder  104 . Detection of the inner stop position and outer stop position is accomplished through a second leaf switch  206  which detects revolutions of a second gear  203  of the gear reduction pair  202 . This is accomplished in this embodiment by providing a face cam  203  on the second gear. Thus, for every revolution of the lead screw  114 , a pulse is generated at the second leaf switch  206 , thus forming a simple incremental encoder. FIG. 10 illustrates the respective signals from the first leaf switch  204  and the second leaf switch  206 . 
     FIG. 11 is a block diagram of circuitry of a printing device for implementing the above-referenced feature. FIG. 11 illustrates a central controller  300  for the printing device, which includes a microprocessor, ROM  302  and RAM  304 . The controller  300  is connected to an LCD driver  309  for driving a display  308  of the printing device. The display  308  and its driver  309  can be located remotely from the printing device itself. The controller  300  also communicates with a keyboard  306  or other input device for receiving information concerning data to be printed and cutting operations and the like. For this, a plurality of keys are provided which are illustrated by way of example as keys  320 , 310 , 312 , and  316 . The keyboard  306  can be located remotely from the printing device itself. The controller  300  is also connected to the printhead  210  and to a tape drive motor  307  for driving the platen  212  to feed tape through the printing device. The printhead  210  and tape drive motor  307  effect printing and feeding operations under the control of the controller  300  in known manner. The controller  300  is also connected to a bidirectional motor control circuit  317  which controls the operations of the cutter drive motor  200 . 
     The controller  300  receives information from the cutter diagnostic switches  204 , 206  illustrated in FIG.  9 . The controller  300  is also connected to cassette diagnostic switches  301  which are located in the cassette receiving bay of the printing device and which identify parameters concerning the cassette and transmit these to the controller  300 . These parameters preferably include the nature of the tape and its width. 
     Referring to FIG. 12, the control circuit  300  receives respective signals from the cutter diagnostic switches  204 , 206  and can thus determine the position of the carriage  110 . It can consequently arrange to reverse the direction of travel of the anvil holder  104  at a selected one of the inner stop position and outer stop position. 
     At step  400 , a cut operation commences. This can be done by the user&#39;s depressing a cut button on the keyboard  306 , or could be automatically initiated by the machine in response to having printed a certain length of label. At step  402 , the controller  300  inquires whether a full cut is required. The user answers this inquiry at the time of formatting the label or at the time of instigating a cutting operation. According to the answer, a number N is set defining the number of encoder pulses to expect from the diagnostic leaf switch  206 . If a full cut is required, the number N is set to N 2 , whereas if a tab cut only is to be implemented, the number N is set to N 1 . It will be apparent that N 1  is less than N 2  because the outbound travel of the carriage  100  for the tab cut only case is less than where a full cut is to be implemented on the return stroke. 
     Step  404  causes the carriage  110  to be driven in the outbound direction by starting the motor  200 . The diagnostic leaf switch  204  determines when the carriage has passed through the home position, as denoted by the transition  405  in FIG.  10 . This transition is detected at step  406  and the controller then proceeds to count the incremental encoder pulses derived from the diagnostic leaf switch  206 . When N equals the preset number (N 1  or N 2  as determined by steps  403   a , 403   b ), the motor direction is reversed at step  407  to drive the carriage  110  in the inbound direction. When the home signal is reached (step  408 ), the sequence is terminated (step  409 ). When the second diagnostic switch  204  is closed, the controller  300  shuts off the DC motor  200 . 
     Thus, a user can request labels with or without a full cut via a user interface of the printing device. Furthermore, a string of score cut labels can be produced and, after the last, the control circuit can cause the cutting mechanism to produce a full cut with the final tab cut, to separate the string from the printing device. More details concerning the manner in which score cut labels, separated by tab cuts, can be produce are disclosed in our U.S. Pat. No. 5,458,423, the content of which is expressly incorporated herein by reference thereto. 
     FIG. 13 is a flow chart illustrating how a string of score cut labels can be produced, with the string being terminated at a full cut. The flow chart in FIG. 13 starts from the point when a user has requested a string of P 1  labels, each label being separated from its neighbor only by a tab cut but remaining attached to a common strip of backing tape. This is denoted as step  500  in the flow chart. 
     Prior to printing of the first label, at step  502  the processor sets P=0. The processor then prints the first label of the string at step  504 . At step  506 , P is incremented, and at step  507  it is compared with P 1 . Naturally, for the first label P will not equal P 1 , and therefore the full cut blade  102  is disengaged as explained above. Only a tab cut is then produced, as illustrated at step  510 . 
     When P=P 1 , the full cut blade is no longer disengaged so that at the next cut the string of labels is cut off while simultaneously performing a tab cut on the final label. This is shown at step  512 . 
     FIG. 14 is a flow chart illustrating how a user selects an appropriate option at the user interface. As described in more detail in our copending British application GB 9614144.5, the printing device has a user interface with a display and various input keys. These input keys include a PRINT key, a set of FUNCTION keys, a SELECT key and a set of DATA INPUT keys. The Function keys include a SET UP key and a SPECIAL key which allow the various cutting options discussed herein to be selected by a user. A print operation is selected by a user by depression of the print key, as indicated at step  600 . By depression of the special key, a menu of label select options is displayed on the screen  603  as illustrated in FIG.  15 . By using cursor keys, a user can mark one of the following displayed options: copies; inc. copies; color; preview; inverse; or serial. 
     A user may also enter a number in the displayed block  601  adjacent the selected option. The processor then determines at step  602  whether or not multiple copies have been selected. If printing only a single label was selected, the processor proceeds to print the label at step  604  and perform a cutting operation implementing a tab cut and a full cut at step  606 . 
     By depression of these set up function keys, a user can cause to be displayed the menu of options illustrated in FIG. 16, giving the cutting options: tab only; or cut tab. If the user has selected a tab only option, this is determined by the processor at step  608 . If a full cut has been selected, a sequence of copies of a label is printed and individually cut off with a full cut as shown in a sequence of steps  610 ,  612  and  614 . 
     If a tab only selection has been made, the user goes into the sequence illustrated in FIG. 13 denoted in block  616  in FIG.  14 . 
     It will be appreciated that the processor will need to make some adjustment for the lead length of a label when it is operating in a score cut mode as opposed to when it is implementing a full cut. This can be adjusted in the manner described and explained in U.S. Pat. No. 4,458,423. 
     As outlined above, the user can select multiple copies of the same label. The printing device can count the number of copies and display that to a user if desired. The display can show how many copies have been printed or how many are remaining to be printed. Moreover, the printing device can be set up to provide incremental copies. That is, the printing device can print a sequence of labels in which each label has a number, subsequent labels having that number plus one. For instance, the first label could be printed with a “1”, the second with a “2”, and so forth. The user can also select a number of labels which are being printed with the same incremental number. Thus, for example the user could select three repetitions of each incremental number, resulting in the first three labels having a “1”, the next three having a “2”, and so on. 
     As a further option, the leader of a label may be reduced by commencing a print operation so that part of the label is printed, then stopping the print operation to perform a tab cut after a predetermined length has been fed, then proceeding to print the complete label. This allows shorter labels to be produced and thus reduces the amount of wasted tape.