Abstract:
A device for imprinting a strip or labels adhering to a strip in which the strip is unwound from a supply roll held by a receiving device and fed to a printing unit. The printing unit can be opened for loading and closed for printing the strip. The printing unit has an automatic actuating device which opens the printing unit as a function of a signal. A holding device securing the supply roll to the receiving device is actuated by an automatic actuating device as a function of a signal so that the holding device releases the supply roll.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Applicant claims priority under 35 U.S.C. §119 of GERMAN Application No. 101 09 882.0 filed on 22 Feb. 2001. Applicant also claims priority under 35 U.S.C. §365 of PCT/EP01/14977 filed on 18 Dec. 2001. The international application under PCT article 21(2) was not published in English. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a device for imprinting a strip or labels adhering to a strip, in which the strip is unwound from a supply roll and supplied to a printing unit, the supply roll being held by a receiving device and the printing unit can be opened for loading a strip and closed for imprinting the strip or labels adhering to the strip. 
     2. Prior Art 
     Printers, as they are typically used in the field of price marking, contain, among other things, a receiving device for the ticket roll (supply roll), which is a flat strip with or without labels adhering thereto, a printing unit, a paper winding device, and an assembly for using thermal transfer film. In order to make the loading of the current ticket roll as simple as possible, the printing unit is typically provided with an opening mechanism. The related art is to open the printing unit through intentional actuation of an actuator, in order to load and/or replace the ticket roll with or without labels. To load the ticket roll, it is placed on an assigned receiving device and possibly fixed there. A specific starting length of the flat strip which forms the ticket roll is guided through the printing unit and attached to a winding device. The winding device may contain a mechanism which simplifies the removal of the flat strip wound thereon. Before the printing procedure may begin, the printing unit must be closed. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to provide a device of the type initially cited, with which the loading and/or changing of a flat strip, with or without labels adhering thereto, is possible in a comfortable way. 
     This object in achieved by a device having the features disclosed herein. Preferred are advantageous embodiments of the present invention are also disclosed. 
     This object is achieved by a device having the features of claim  1 . Preferred and advantageous embodiments of the present invention are specified in the subclaims. 
     The present invention is thus essentially that the printing unit of the device is provided with an automatic actuating device which automatically opens the printing unit as a function of a signal, and a holding device, which secures the supply roll on the receiving device during the printing procedure, is automatically actuated by the automatic actuating device or another automatic actuating device as a function of the said signal or another signal, so that the holding device releases the supply roll. 
     With the device according to the present invention, the strip wound on a supply roll may therefore be placed and/or replaced on the receiving device and the strip may be loaded through the printing unit up to the winding device and fixed easily and comfortably. 
     The signal which causes the automatic opening of the printing unit and/or the automatic actuation of the holding device to release the supply roll may be generated in various ways. According to a preferred embodiment, the signal is generated using a measurement device which detects the end of the strip and/or using a device which calculates the end of the strip. The measurement device for detecting the end of the strip may preferably have a switch, a touch element, a magnetic sensor, and/or a light barrier in this case. 
     A further preferred embodiment of the device according to the present invention is that the signal which causes the automatic opening of the printing unit or the automatic actuation of the holding device to release the supply roll is transmitted wirelessly and/or via optical fiber to the respective automatic actuating device. The respective automatic actuating device may preferably be implemented as an electromechanical, electromagnetic, or pneumatic actuating device in this case. 
     According to a further advantageous embodiment, the device according to the present invention may be implemented in such a way that the automatic opening of the printing unit and the automatic actuation of the holding device to release the supply roll occur at different times. The time delay with which the automatic actuation of the holding device to release the supply roll follows the automatic opening of the printing unit may be fixed or adjustable. 
     Furthermore, the device according to the present invention may also have a winding device for winding the strip coming out of the printing unit, which is provided with a mechanism for removing the wound strip and with a sensor which detects the position of the mechanism for removing the wound strip. For such an embodiment, the sensor preferably generates the signal which causes the automatic opening of the printing unit or the automatic actuation of the holding device to release the supply roll when the mechanism for removing the wound strip is in a position which is provided for removing the wound strip. Alternatively, leaving the starting position, i.e., the position which is provided for the winding of the strip, may be used for signal generation. All active and passive sensors, as well as switches and/or pneumatic valves, may be used as sensors in this case. 
     The manipulations of the operator of the device according to the present invention may be reduced to minimum if this device also includes a measurement device which detects the placement of a supply roll on the receiving device and proper loading of the strip and which, in the event of a supply roll positioned on the receiving device and a properly loaded strip, generates a signal which causes automatic actuation of the holding device to secure the supply roll on the receiving device and automatic closing of the printing unit. In this way, the initial loading of a strip and the replacement of a supply roll are optimally supported by the device according to the present invention. The automatic actuation of the holding device to secure the supply roll on the receiving device and the automatic closing of the printing unit may also occur at different times in this case. 
     After the automatic actuation of the holding device to secure the supply roll, the latter is therefore mechanically fixed, however, it may possibly not yet be optimally seated at the intended position. According to a further advantageous embodiment of the device according to the present invention, a device for automatic alignment of the supply roll on the receiving device is therefore provided. The alignment of the supply roll may advantageously be performed using an electromechanical, electromagnetic, or pneumatic actuating device in this case. A control device of this type may preferably also be used for the automatic closing of the printing unit. 
     A further advantageous embodiment of the device according to the present invention is that the printing unit is assigned a device for automatic positioning of labels adhering to the band strip in relation to the printing unit. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the following, the present invention is described in greater detail on the basis of a drawing which illustrates an exemplary embodiment. 
     FIG. 1 shows a schematic illustration of a device according to the present invention, 
     FIG. 2 shows a schematic sectional illustration of a receiving device for receiving a supply roll, 
     FIG. 3 shows a schematic illustration of a winding device having a mechanism for removing a wound strip, and 
     FIG. 4 shows a schematic illustration of the winding device shown in FIG. 3, the mechanism for removing a wound strip being located in a position in which the wound strip may be removed. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A printer for printing labels  2  adhering to a carrier strip  1  is illustrated in FIG.  1 . The strip  1  is unwound from a supply roll  3  and fed to a printing unit  4 . The printing unit  4  includes a printing head  5  and a printing roller  6 . The printing head  5  presses the labels with sufficient force against the printing roller  6  and imprints them using the thermal or thermal transfer method, for example. The printing roller  6  may be driven by a stepping motor (not shown). A relatively sharp deflection in the form of a dispensing edge  7  is provided in the strip run direction behind the printing unit, on which the printed labels are detached in a way known per se from the carrier strip  1  and may be removed through an opening in the housing of the printer and applied to an object to be identified. After the deflection on the dispensing edge  7 , the carrier strip  1  is wound on a winding device  9  driven by a stepping motor  8 . 
     The printing head  5  of the printing unit  4  is attached to a movably mounted plate  10 , on which coil springs  11 , supported on fixed bearings, engage on the side of the printing head  5 . An eccentrically mounted circular disk  12 , which may be rotated by a stepping motor  13 , is on the other side of the plate  10 . Due to the spring action, the printing head  5  is moved away from the printing roller  6  upon rotation of the eccentrically mounted circular disk  12 , so that the printing head  5  assumes a sufficiently large distance in relation to the printing roller  6  to be able to guide the strip  1 , having the labels  2  adhering thereto, comfortably through the printing unit  4 . 
     The supply roll  3  is placed on a receiving device which is provided with a holding device which secures the supply roll  3  on the receiving device during the printing procedure. A possible embodiment of the receiving device is schematically illustrated in FIG.  2 . The receiving device  14  has a cylindrical receiving core rod  15 , which penetrates a bearing disk  16 , implemented as circular, for example, and is permanently connected thereto. The receiving core rod  15  has a bore  17  running along its longitudinal axis, whose ends are closed by a cap  18 , a screw cap, for example, and a platelike cover  19 , respectively. In the bore  17 , a pin  20 , displaceable in the lengthwise direction, is positioned, which has a coil spring  21 , supported on the cover cap  18 , applied to it on its face assigned to the cover cap  18 . The other end of the pin  20  is implemented as conical and is in contact with a further, smaller pin  22 , which is received in a radially positioned through bore of the receiving core rod  15 . On its end facing toward the other pin  20 , the smaller pin  22  has an enlarged head  23 , which a coil spring  24  presses against, which is supported on a shoulder  25  of the radially positioned bore. 
     The pin  20 , displaceable in the lengthwise direction of the receiving core rod  15 , has a magnetic section  26  and is otherwise made of a non-magnetic material. The magnetic section  26  is assigned an annular electromagnet  27 , which is embedded in the wall of the receiving core rod  15  between the cover cap  18  and the bearing disk  16 . Upon activation of the electromagnet  27 , the pin  20  is moved against the force of the coil spring  21  in the direction of the cover cap  18 , the smaller pin  22  positioned in the radial bore of the receiving core rod  15  moving radially inward due to the effect of the coil spring  24  assigned to it and the conically implemented end of the pin  20 . A supply roll placed on the receiving core rod may be removed from the receiving device in this setting of the pins  20 ,  22 . In contrast, if the electromagnet  27  is deactivated, the pin  20 , displaceable in the lengthwise direction, moves in the direction of the cover plate  19  at the other end of the receiving core rod  15  due to the effect of the coil spring  21 . The head  23  of the small pin  22 , whose diameter is enlarged, slides along the conically implemented section  28  of the pin  20  in this case and the pin  22  is thus moved radially outward against the force of the coil spring  24  assigned to it, so that it projects in relation to the lateral surface of the receiving core rod  15 . The core of a supply roll  3  positioned on the receiving core rod  15  is mechanically fixed on the receiving device in this way. The supply roll  3  is released via another activation of the electromagnet  27 . Only one radially positioned pin  22  is illustrated in FIG.  2 . However, the receiving core rod  15  may also be provided with multiple radially positioned pins, with three pins, for example, which each have a spacing of 120° to one another when distributed uniformly around the circumference. 
     The printing unit  4  of the device and the holding device described above, which secures the supply roll  3  on the receiving device  14  during the printing procedure, are automatically opened and/or actuated as a function of a signal. The signal which causes the automatic opening of the printing unit  4  and automatic actuation of the holding device to release the supply roll  3  is generated in the exemplary embodiment illustrated using a measurement and control device  29  which detects the end of the strip  1  (cf. FIG.  1 ). For this purpose, the measurement and control device  29  has a light barrier which includes a light-emitting transmitter diode  30  and a receiver diode  31  assigned thereto. If the end of the carrier strip  1  passes the region of the light barrier, the receiver diode  31  receives the light emitted by the transmitter diode  30 , upon which a signal is generated in the measurement and control device  29 , which is conducted via signal lines  32 ,  33  to the stepping motor  13  assigned to the eccentrically mounted circular disk  12  and to the electromagnets  27  of the holding device, which secure the supply roll on the receiving device during the printing procedure. 
     The winding device  9  schematically illustrated in FIGS. 3 and 4 is provided with a mechanism which is used for removing the strip  1  wound there. The winding device  9  includes a rotatably mounted, circular bearing disk  34  having a centrally positioned cylindrical winding core rod  35 , which is provided with a slot  36  for fixing the beginning of the carrier strip  1 . The rotatably mounted bearing disk  34  is assigned a second bearing disk  37 , running essentially parallel thereto, which is mounted so it is movable in the direction of the axis of rotation  38  of the winding core rod  35 . For this purpose, the second bearing disk  37  is provided with a pin  39  on its side facing away from the winding core rod  35 , which penetrates a corresponding opening  41  implemented in a holder  40  with play and has a head  42 , whose diameter is expanded, on its end facing away from the bearing disk  37 . A coil spring  43 , placed on the pin  39 , is positioned between the holder  40  and the bearing disk  37 . The bearing disk  37  may be moved away from the winding core rod  35  against the action of this coil spring  43 , as shown in FIG. 4, so that a strip coil (not shown) located on the winding core rod  35  may be removed from the winding device  9 . 
     Two electrical contacts  44 ,  45  are implemented on the fixed holder  40 , which may be short-circuited by an annular conductor  46  implemented on the expanded head  42  of the pin  39  when the bearing disk  37  is pressed in the direction of the winding core rod  35  due to the effect of the coil spring  43  (cf. FIG.  3 ). A two-wire signal line  47  leads from the electrical contacts  44 ,  45  to the measurement and control device  29 , as shown in FIG.  1 . In contrast, if the bearing disk  37  is moved away from the winding core rod  35 , as shown in FIG. 4, the electrical connection between the contacts  44 ,  45  is interrupted. In this way, a signal is generated which may also be used for automatic opening of the printing unit  4  and/or for automatic actuation of the holding device to release the supply roll  3 . 
     As shown in FIG. 1, the measurement and control device  29  is provided with a second light barrier which is positioned between the label dispensing edge  7  and the winding device  9 . The light barrier again includes a transmitter diode  48  and a receiver diode  49  assigned thereto, which are connected via signal lines  50 ,  51  to the measurement and control device  29 . 
     Using the two light barriers, the interrupter switch made of the contacts  44 ,  45  and the conductor  46 , and a sensor (not shown), in the form of a touch switch, for example, positioned on the receiving device  14 , the positioning of a supply roll  3  on the receiving device  14  and proper loading of the strip  1  into the printer may be detected and, if there is a supply roll  3  present and a properly loaded strip  1 , a signal may be generated in this way which causes automatic actuation of the holding device to secure the supply roll  3  on the receiving device  14  and automatic closing of the printing unit  4 . The supply roll  3  is then seated mechanically fixed on the receiving core rod  15  of the receiving device  14 , but possibly not yet optimally at the intended position. For optimal alignment of the supply roll  3  on the receiving core rod  15 , a mechanism is provided (not shown), which is capable of displacing the position of the entire supply roll  3 . This mechanism may be activated electromechanically and/or mechanically and/or pneumatically. 
     The exemplary embodiment described above makes it clear that the initial loading of a supply roll  3  and/or of a carrier strip  1  and supply roll replacement are optimally supported by a printer according to the present invention. The manipulations of the operator are reduced to a minimum. 
     The implementation of the present invention is not restricted to the exemplary embodiment described above. Rather, a number of variants are conceivable which make use of the inventive idea as disclosed in the claims, even in the event of fundamentally differing construction. 
     LIST OF REFERENCE NUMBERS 
       1  carrier strip 
       2  labels 
       3  supply roll 
       4  printing unit 
       5  printing head 
       6  printing roller 
       7  dispensing edge 
       8  stepping motor 
       9  winding device 
       10  plate 
       11  coil springs 
       12  circular disk (eccentrically mounted) 
       13  stepping motor 
       14  receiving device 
       15  receiving core rod 
       16  bearing disk 
       17  bore 
       18  cover cap 
       19  cover (platelike) 
       20  pin 
       21  coil spring 
       22  pin 
       23  head 
       24  coil spring 
       25  shoulder 
       26  electromagnetic section 
       27  electromagnet 
       28  conically implemented section 
       29  measurement and control device 
       30  transmitter diode 
       31  receiver diode 
       32  signal line 
       33  signal line 
       34  bearing disk 
       35  winding core rod 
       36  slot 
       37  bearing disk 
       38  axis of rotation 
       39  pin 
       40  holder 
       41  opening 
       42  pin head (diameter expanded) 
       43  coil spring 
       44  electrical contact 
       45  electrical contact 
       46  annular conductor 
       47  signal line 
       48  transmitter diode 
       49  receiver diode 
       50  signal line 
       51  signal line