Patent Abstract:
There is disclosed a portable printer operable in either a strip mode or a peel mode. In the peel mode, a pressure roll cooperates with a carrier web and the platen roll to strip labels from the web. A battery-powered electric motor advances a printable web through the printer. In order to reduce drag on the motor in the strip mode, the pressure roll is held in out of pressure contact with the platen roll.

Full Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates to printers that print on printable webs including label webs and to printing methods.  
         [0003]     2. Brief Description of the Prior Art  
         [0004]     The following U.S. Patents are made of record: U.S. Pat. Nos. 5,049,228; 5,486,259; 5,525,184; 5,892,531; 6,241,407; and 6,261,013. Also made of record is Seiko Instruments, Inc., LTP V Series Thermal Printer Mechanism Technical Reference U00060114300 dated July 2001.  
       SUMMARY OF THE INVENTION  
       [0005]     A specific embodiment of the invention provides an improved printer operable in either a strip mode wherein a printable strip is printed and dispensed or in a peel mode wherein labels on a carrier web are printed and are peeled or dispensed from a carrier web, wherein the printable strip can comprise, for example, a composite web with labels releasably adhered to a carrier web or a web of receipt material. The printer has a print head such as a thermal print head, a driven platen roll cooperable with the print head, a delaminator disposed downstream of the print head, and a pressure roll disposed downstream of the delaminator. The pressure roll is mounted to be out of cooperation with the platen roll in the strip mode to reduce the drag on the electric motor that advances the printable strip in the strip mode. However, in the peel mode the pressure roll is in pressure cooperation with the carrier web and the platen roll. The pressure roll is selectively positionable for operation in either the strip mode or the peel mode. A specific embodiment of a method includes selectively positioning the pressure roll out of pressure cooperation with the platen roll in the strip mode or in pressure cooperation with the carrier web and the platen roll in the peel mode. A specific embodiment includes a holder for the pressure roll, wherein a tear bar is on or a part of the holder. 
     
    
     BRIEF DESCRIPTION OF THE DIAGRAMMATIC DRAWINGS  
       [0006]      FIG. 1  is a perspective view of a printer in accordance with the invention;  
         [0007]      FIG. 2  is a perspective view of the printer depicted in  FIG. 1 , with a door or housing section in an open position;  
         [0008]      FIG. 3  is a sectional view through the printer showing the printer in the strip mode;  
         [0009]      FIG. 4  is an elevational view of the printer with a housing portion removed;  
         [0010]      FIG. 5  is a fragmentary view similar to  FIG. 3 , but showing the printer in a peel mode;  
         [0011]      FIG. 6  is an exploded perspective view of the platen roll and its mounting structure and a pressure roll and tear bar mechanism;  
         [0012]      FIG. 7  is a perspective view of a label roll holding mechanism;  
         [0013]      FIG. 8  is an exploded perspective view of the pressure roll and tear bar mechanism;  
         [0014]      FIG. 9  is a perspective view of the printer with its door open to show the peel mode;  
         [0015]      FIG. 10  is a perspective view of the printer with its door open to show the strip mode;  
         [0016]      FIG. 11  is a perspective view of one of the housing sections;  
         [0017]      FIG. 12  is a perspective view of the door;  
         [0018]      FIG. 13  is an exploded perspective view of a housing section and a print module;  FIG. 14  is a sectional view showing a stop or actuator in a peel mode position;  
         [0019]      FIG. 15  is a sectional view showing the stop in a strip mode position;  
         [0020]      FIG. 16  is a perspective view showing the stop in its peel mode position;  
         [0021]      FIG. 17  is a fragmentary side elevational view of the door or housing section; and  
         [0022]      FIG. 18  is an exploded, perspective view of the door with the outer panel removed, and the platen and tear bar holder.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]     With reference to  FIG. 1 , there is shown a portable printer generally indicated at  20  having a housing  21  with a door  22  at the front of the printer  20 . The door  22  has an outer panel  22 ′ and an inner panel  22 ″ ( FIGS. 2 and 18 , for example). The outer panel  22 ′ and the inner panel  22 ″ are connected by screws  19  ( FIG. 18 ) secured to bosses (not shown) on the inside of the outer panel  22 ′. Latch handles  23  (only one of which is shown in  FIG. 1 ) at both sides of the front door  22  are used to unlatch the front door  22  from the remainder of the housing  21 . The upper portion of the housing  21  has keys  24  and a display  25 . The door  22  mounts a label roll holder mechanism generally indicated at  26  with opposed annular projections  27  (only one of which is shown in  FIG. 2 ). The annular projections  27  are received in the central opening of a label roll (not shown). A platen roll  28  mounted on a central shaft  29  on which bearings are received. A gear  31  is secured to one end portion of the shaft  29 . The latch handles  23  form part of a latch generally indicated at  32  which includes latch hooks  33 . The door  22  is pivotally mounted to the rest of the housing  21  by a hinge pin  34 . The printer  20  is powered by a rechargeable battery  35 .  
         [0024]     With reference to  FIG. 3 , the platen roll  28  is driven by gearing  31 ′ ( FIG. 4 ) which meshes with the gear  31 . The gearing  31 ′ and in turn the gear  31  are driven by an electric motor  36 . A print head  37  ( FIG. 3 ) is mounted by a holder  38  pivotable about a pin  39 . A compression spring  40  urges the holder  38  and the print head  37  counterclockwise in  FIG. 2  toward the platen roll  28 . A roll R of a composite web C is comprised of a carrier web W to which labels L are releasably adhered. In the strip mode shown in  FIG. 3 , the composite web C is paid out of the roll R as the driven platen  28  rotates during label printing on the labels L. The carrier web W and the labels L pass over a delaminator  41 . The delaminator  41  is shown to be a peel bar, but alternatively, the delaminator  41  can comprise a peel roller (not shown). The springs  40  urge the print head  37  against the composite web C which passes against the platen roll  28 . The delaminator  41  is disposed downstream of the place where the print head  28  exerts pressure against the composite web C and the platen roll  28 . In the strip mode, the delaminator  41  is ineffective to peel labels L from the web W. In the peel mode illustrated in  FIG. 5 , the carrier web W passes from the delaminator  41  to between a pressure roll  42  and the platen roll  28  and from there the web W exits the printer  20 .  
         [0025]     With reference to  FIGS. 6 and 7 , and initially to  FIG. 6 , the pressure roll  42  is shown to be mounted on a holder or carrier  43 . The holder  43  has arms  44  with snap sockets  45 . The pressure roll  42  is of one-piece molded plastics construction and has stub ends  46  received in the snap sockets  45 . The pressure roll  42  is free to rotate in the snap sockets  45 . The arms  43  also mount a tear bar  47  having a tear edge  48 . The arms  44  are joined to a transverse section or member  49 . Joined to the section  49  are a pair of arms  50  spaced apart more widely than arms  44 . The arms  50  have guides  51  which through-holes  52  ( FIG. 7 ). Pins  53  have heads  54 . The pins  53  are slidably received in through-holes  52 . Compression springs  55  received on the pins  53  bear against heads  54  and against shoulders  56  of the guides  51 . The pins  53  have grooves  57  which receive E-rings  58 . The springs  55  are preferably in slight compression when E-rings  58  abut shoulders  59 . The section  49  has posts  60  and annular projections  61  spaced outwardly of the posts  60 . Compression springs  62  are received about the posts  60  within the annular projections  61  so that the springs are located with respect to the holder  43 . The holder  43  also has a pair of outwardly extending pivots or posts  63  snapped into sockets  64  ( FIG. 4 ). It is noted that the pivots  63  are between the pressure roll  42  and the places where the springs  62  bear against the holder  43 . The springs  62  bear against the housing as shown in  FIGS. 3 and 5  and are normally under compression as they urge the holder  42  counterclockwise to the position shown in  FIG. 3 . It is noted that in this position, the heads  54  of the pins  53  are out of contact with positionable stops or actuators  64 . In  FIGS. 3 and 10  the stops  64  are in the ineffective positions out of contact with heads  54 , and accordingly, the stops  64  have no affect on the holder  43 . The springs  62 , therefore, set or control the position of the pressure roll  42 , namely, the pressure roll  42  is urged out of pressure contact with the platen roll  28 . In the  FIG. 3  position, the pressure roll  43  is out of contact with the platen roll  28 . This reduces drag on the motor  36  in the strip mode depicted in  FIG. 3 .  
         [0026]      FIG. 5  is like  FIG. 3  except that in  FIG. 5  the holder  43 , the pressure roll  42  and the stops  64  are in their peel mode positions. In  FIG. 5 , the head  54  is shown to abut the stop  64 , and the spring  55  is more compressed than shown in  FIG. 3 . The forces of the springs  62  are overcome and the pressure roll  42  are shown in pressure cooperation with the carrier web W and the platen roll  28 . In particular, the pressure roll  42  is in pressure contact with the carrier web W and the carrier web W is in pressure contact with the platen roll  28 . Thus, the carrier web W is sandwiched between the pressure roll  42  and the driven platen roll  28  downstream of the delaminator  41 . Accordingly, rotation of the platen roll  28  advances or moves the carrier web W so that the leading label L is peeled from the carrier web W at the delaminator  41 . The carrier web W exits the printer through the space  77  between the tear bar  76  and the transverse section  49  of the holder  43 . By simply repositioning the stops from their ineffective positions ( FIGS. 3 and 10 ) to their effective positions ( FIGS. 5, 9  and  14 ) the printer  20  can be changed from its strip mode to its peel mode, and vice versa.  
         [0027]     The stops  46  are identical. Each stop  46  is pivotally mounted on a pin  90  for movement between the peel mode position shown in  FIGS. 9, 14  and  16  and the strip mode position shown in  FIGS. 10 and 15 . The housing has a pair of projections  91  that fit between pairs of abutments  92  and  93  when the stop  46  is in the peel mode position ( FIG. 14  for example). Both sides of the stops  46  are the same although only one side is shown, each side having a pair of abutments  92  and  93  cooperable with a respective projection  91 . In that the stops  46  and the housing  22  in which the stops  46  are pivotal are constructed of plastics material, the stops  46  can be pivoted clockwise from the  FIG. 14  position to the  FIG. 15  position, and there is enough yield or give between the projections  91  and the abutments  93  to enable such pivotal movement. The stops  15  can be returned from the  FIG. 15  position to the  FIG. 14  position by the abutments  93  and the projections  91  yielding. The projections  91  and the abutments  92  and  93 , therefore, provide a detent for the stops  46 .  
         [0028]     The holder  43  and the pressure roll  42  are each of one-piece molded plastics construction.  
         [0029]     With reference to  FIG. 8 , the label roll holder  26  includes a pair of holder members  78  each having a straight gear or rack  79 . A gear  80  rotatable on a stud secured to the housing is coupled to the racks  79 . Screws  81  secured to the housing  21  are connected to tension springs  82 . The tension springs  82  are also connected to the holder members  78  as best shown in  FIG. 8 . The holder members  78  mount opposed identical, roll-engaging members  83  between which a label roll R is held. The members  83  are preferably rotatable on holder members  78  to minimize the drag on the motor as the label roll unwinds upon rotation of the platen roll  28 . The springs  82  pull on the holder members  78  and urge members  83  toward each other. The arrangement of the gear  89  and racks  79  causes the holder members  78  and the members  83  to move relatively toward and away from each other when manual force is applied against holder members  78  or the members  83 .  
         [0030]     The housing  21  has a compartment  95  for a radio (not shown) and a cover  96  securable to the housing  21  for closing off the compartment  95 .  
         [0031]     The print head module M mounted in the housing  21  includes the motor  36 , print head  37 , holder  38 , pivot  39 , spring  40  and gearing  31 ′ and is shown in assembled form in  FIG. 13 . The module M is a subassembly which can comprise, for example, an LTP V Series thermal printer mechanism of Seiko Instruments, Inc.  
         [0032]     Other embodiments and modifications of the invention will suggest themselves to those skilled in the art, and all such of these as come within the spirit of this invention are included within its scope as best defined by the appended claims.

Technology Classification (CPC): 8