Printer and methods

Information

  • Patent Grant
  • 6533476
  • Patent Number
    6,533,476
  • Date Filed
    Thursday, April 18, 2002
    22 years ago
  • Date Issued
    Tuesday, March 18, 2003
    21 years ago
Abstract
There is disclosed a portable thermal printer having a printer housing, a printing mechanism and an ink ribbon cartridge containing an ink ribbon cartridge containing an ink ribbon. The cartridge has a cartridge housing and an improved brake for applying a slight braking force on a core of an ink ribbon supply roll in the housing. The cartridge is easy to load onto the printer. The cartridge forms part of the printer housing and is latched thereto. The cartridge is slid onto the printer and the cartridge housing detents into position.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




This invention relates to the field of printers and ink ribbon cartridges and methods pertaining thereto.




2. Brief Description of the Prior Art




The following prior art is made of record: U.S. Pat. Des. Nos. 327,495; 2,764,934; 3,774,538; 4,160,605; 4,479,730; 4,581,616; 4,609,298; 4,611,218; 4,655,623; 4,673,304; 4,685,815; 4,702,631; 4,776,714; 4,830,523; 4,832,514; 4,899,172; 4,910,602; 4,914,452; 4,915,516; 4,924,242; 4,944,619; 4,957,379; 4,970,531; 5,035,325; 5,128,763; and British patent 1,455,915.




SUMMARY OF THE INVENTION




The invention relates to an improved, user-friendly, compact, portable, small-footprint, easy-to-use printer.




A feature of the invention is an improved ink ribbon cartridge. A specific embodiment of the cartridge is comprised of a cartridge housing with a stationary shaft and a brake member on the shaft in frictional contact with an inner surface of a core of an ink ribbon roll. The brake member cooperates with the core to prevent an excessive amount of ink ribbon to be paid out during the printing operation and to maintain tension in the ink ribbon.




Another feature of the invention is the new use of a tubular member as a brake member cooperating with the inner surface of a core of an ink ribbon roll.




Another feature of the invention resides in an improved arrangement for coupling an ink ribbon cartridge into a printer. In a specific embodiment, the ink ribbon cartridge includes a housing with first and second housing members spaced apart to provide an opening. The print head has a line of printing elements and is mounted on a support. The cartridge is mounted onto the printer so that the support and the print head enter the opening between the housing members of the cartridge.




It is another feature of the invention for the cartridge to have a flexible resilient housing wall within which the ink ribbon is based. The housing wall deflects resiliently while the cartridge is being inserted until the housing wall encounters a recess which causes the cartridge to detent essentially into its operating position.




It is a feature of the invention to provide an improved arrangement for detenting a cartridge in a printer.




It is a feature of the invention to provide an ink ribbon cartridge that forms part of an improved housing assembly of a printer. In a specific embodiment, a portion of the cartridge is received in the printer housing and another portion extends outside the printer housing. The print head is mounted on a support and the cartridge has an opening for receiving the support. The printer, thus, has a very compact organization.




It is a feature of the invention to provide an improved housing assembly for a printer in which the printer includes a printer housing and an ink ribbon cartridge coupled to the printer housing. In a specific embodiment, the cartridge is located and latched in its operating position, preferably by a toggle mechanism.




It is a another feature of the invention to provide a thermal printer operable in both thermal direct and thermal transfer modes, wherein an ink ribbon cartridge housing is effective for forming a portion of the guideway for the web to be printed upon and for providing part of the printer housing during operation in the thermal direct mode, and wherein the cartridge housing is effective additionally for supplying ink ribbon to the thermal print head during operation in the thermal transfer mode.




Other features of the invention will be evident to one skilled in the art by reference to the drawings, the following description and the appended claims.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of the printer of the invention





FIG. 2

is a vertical sectional view of the printer;





FIG. 3

is a view similar to

FIG. 2

but showing the printer in its open position and showing the ink ribbon cartridge exploded away;





FIG. 4

is an exploded perspective view of a mounting section and a print head assembly mounted by the mounting section;





FIG. 5

is an exploded perspective view of a housing section which mounts the mounting section of

FIG. 4

;





FIG. 6

is an assembled view of the mounting section and print head assembly shown in FIG.


4


and the mounting section shown in

FIG. 5

;





FIG. 7

is an exploded perspective view of an assembly for latching the ink ribbon cartridge and for guiding a carrier web of composite label web;





FIG. 8

is an enlarged sectional view of the assembly shown in FIG.


7


and associated components;





FIG. 9

is a fragmentary view showing the manner in which the print is located relative to the platen;





FIG. 10

is an exploded perspective view showing the drive mechanism or the printer and the ink ribbon cartridge;





FIG. 11

is an exploded perspective view of the ink ribbon cartridge;





FIG. 12

is an exploded rotated perspective of cartridge housing sections shown in

FIG. 11

;





FIG. 13

is a sectional view of the cartridge showing a brake;





FIG. 14

is a view showing a fragmentary portion of the cartridge a drive spindle; and





FIG. 15

is a rear elevational view of the cartridge.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




With reference to

FIG. 1

, there is shown a printer generally indicated at


20


which includes a housing generally indicated at


21


. The printer


20


has a relatively small footprint so that its base


22


only occupies a small area on a supporting surface. The housing


21


extends generally vertically, as shown with its vertical extent being relatively long. The printer


20


can also be worn by an operator using a suitable carrying strap (not shown). The housing


21


and a housing


23


of an ink ribbon cartridge generally indicated at


24


form a housing assembly


25


.




The housing mounts an on/off surface


26


, a light


27


for showing whether the printer


20


is “on” or “off”, and certain printer error conditions, and aligned recesses


28


(only one of which is shown) at opposite sides of the housing for connecting the ends of the carrying strap to the housing


21


.




With reference to

FIG. 2

, the housing


21


is shown to removably mount a battery pack


29


containing a series of rechargeable batteries


30


. A spring-urged latch


31


releasably holds the battery pack


29


in position. The housing


21


also mounts electronic controls generally indicated at


32


.




The housing


21


mounts a pair of opposed hub members


33


, only one of which is shown, for mounting a roll R of record members. The illustrated roll R is shown to be a composite web C comprised of a carrier web W and labels L releasably adhered to the carrier web W along its length. However, the roll R can alternatively be comprised of a web of tags (not shown). The housing


21


has a chamber


33


′ which receives the roll R. The chamber


33


is comprised of opposed concave arcuate walls


34


and


35


. The wall


34


merges with a guide


36


which helps guide the composite web C (or the tag web as the case may be) from the roll R to between a print head


37


and a platen roll


38


. The housing


21


also includes mounting sections


39


and


40


. The mounting section


39


is pivotally mounted on posts


41


received in opposed holes


42


. The mounting section


39


includes the wall


35


. The mounting section


40


is pivotally connected to the mounting section


39


. The mounting section


40


has a generally vertically extending outer wall portion


43


and a shelf or generally horizontally extending portion


44


. The shelf


44


has a pair of spaced arm or support portions


44


′ which mount the cartridge


24


. The arm portions


44


′ are received in respective U-shaped channels


130




u


and


131




u


in the cartridge housing


23


. The channel


130




u


is comprised of ribs


130




a


,


130




b


and


130




c


, and the channel


131




u


is comprised of ribs


131




a


,


131




b


and


131




c


. The shelf


44


mounts a print head assembly


45


. The ink ribbon cartridge


24


is received on the printer


20


as best shown in FIG.


2


. An assembly generally indicated at


46


is used to latch the housing


23


of the cartridge


24


and mounting section


40


to the housing


21


and to guide the carrier web W.




As shown in

FIG. 4

, the mounting section


40


mounts the print head assembly


45


. The print head assembly


45


includes a plate


46


which extends generally horizontally. The plate


46


has an upturned curved plate portion


47


(

FIGS. 2

,


3


and


4


) which terminates at a downwardly extending knife-shaped edge


48


(FIGS.


3


and


4


).




A depending guide


49


having an inverted U-shaped guide surface


50


is connected to each end of the plate


46


. An ink ribbon guide


51


is mounted to the plate portion


47


. When correctly adjusted the guide


51


causes the ink ribbon IR to track correctly. The plate portion


47


has a depending stud


52


which is received in a hole


53


in the guide


51


. The guide


51


has an integrally formed plate


54


. The guide


51


also has an L-shaped bracket


55


which is located above the upper surface of the plate


46


. An adjusting screw


57


passes through a slot


58


in the plate portion


47


and is threadably received in a threaded hole


56


in an upstanding portion


56


′ of the bracket


55


. The screw


57


extends through a compression spring


59


which bears against the upstanding portion


56


′ of the bracket


56


and against the plate portion


47


. The angular position of the ribbon guide


51


relative to the plate


46


and the print head


37


can be changed by rotating the screw


57


. Rotation of the screw


57


causes the guide


51


to pivot about the stud


52


. The compression spring


59


retains the guide


51


in its adjusted position. A mounting plate


60


which constitutes a heat sink for the print head


37


is secured to the underside of the plate


46


between the guides


49


. The plate


54


is movably supported by and against the upper surface of the plate


60


. Screws


61


secure the plates


46


and


60


to each other. Compression springs


62


are received in cup-shaped members


63


in the shelf


44


and bear against the upper surface of the plate


46


. A tab


64


having an aperture


65


is secured to the plate portion


46


. The tab


64


projects into a cross-shaped recess


66


. The recess


66


has a first slot portion


67


which receives the tab


64


with clearance. The recess


66


also has a second slot portion


68


which bottoms out as shown in

FIG. 2

for example. The slot portions


67


and


68


are perpendicular to each other. A round pin


66


′ passes through the hole


65


with clearance and rests in the slot portion


68


. When the printer is in the operating position, the springs


62


are under greater compression than when the print head


37


is moved away from the platen roll


38


. As seen in

FIGS. 2 and 4

, the shelf


44


has elongate grooves


69


. In the position of

FIG. 2

, the knife edge


48


is spaced from parallel grooves


69


. When the print head


37


and platen roll


38


are separated, the springs


62


will urge the print head assembly


45


to a position at which the knife edge


48


bears against one of the grooves


69


as shown in FIG.


3


. Thus, the print head assembly


45


is held in approximately aligned position relative to the platen roll


38


.




The mounting section


40


is shown to have a pair of annular portions


70


having aligned holes


71


. Mounting section


39


(

FIG. 5

) also has a pair of annular portions


72


with opposed studs


73


received in the holes


71


. The annular portions


72


also have studs


74


which are received in arcuate slots


75


in annular portions


70


. The studs


74


cooperate with the ends of the slots


75


to limit the amount of rotation of the mounting section


40


relative to the mounting section


39


.




With reference to

FIG. 5

, the mounting section


39


is shown to include an outer wall


35


′. The wall


35


′ mounts a pair of latches


76


guided in respective guides


77


and urged in opposite directions by compression springs


78


. The latches


76


are manually movable and accessible through openings


79


. The latches


76


have respective latch teeth


80


received in opposed pockets


81


(only one of which is shown in FIG.


2


). The wall


35


is secured to the outer wall


35


′ by screws


82


.




With reference to

FIG. 7

, the assembly


46


is shown in exploded form. Member


83


is shown to have a pair of latching grippers


84


. As shown in

FIGS. 2 and 8

, the gripper


84


grips a surface


85


in the ink ribbon cartridge housing


23


. The member


83


has a pair of spaced depending portions


86


which have aligned holes


87


. A rod


88


passes through the holes


87


and through aligned holes


89


in a member


90


. A rod


91


passes through holes


92


in the member


90


and through a hole


93


in a fixed member


94


. When the assembly


46


is in the position shown in

FIGS. 2 and 8

, the members


83


and


90


, which form a toggle linkage, are in an overcenter or latching condition. As shown for example in

FIG. 8

, the grip member


85


on the cartridge housing


23


is gripped by the latching gripper


84


. The rod


88


overcenter with respect to a centerline CL to provide a toggle linkage or mechanism.




As seen in

FIGS. 2 and 8

, a leaf spring


83


′ secured to studs


89


′ on the member


83


is used to urge the carrier web W against the platen roll


38


. The leaf spring


83


′ ensures that there is sufficient contact between the carrier web W and the platen roll


38


. The leaf spring


83


′ has a connector portion


83


″ with holes


83




a


. Oversize holes


83




b


in the leaf spring


83


′ allow fasteners


83




c


to pass freely therethrough and to be press fitted onto the studs


89


′.




As seen in

FIG. 8

, a screw


83




d


is adapted to hold an optional tear bar (not shown).




With reference to

FIG. 10

, a drive mechanism is generally indicated at


94


. The drive mechanism


94


includes an electric motor


95


for driving a gear


96


. The gear


96


meshes with gears


97


and


98


. Coaxially secured to the gear


97


is a gear


99


which meshes with a gear


100


. The gear


100


has a non-circular hole


100


′ which receives a non-circular end portion


101


of a shaft


102


. The platen


38


is comprised of a sleeve of resilient frictional material on the shaft


102


. The shaft


102


is mounted in spaced bearings


103


. The bearings


103


are mounted in bearing housings


103


′ mounted in the housing


21


.




The gear


98


is secured to an axially aligned gear


104


which meshes with a gear


105


. The gear


105


meshes with a gear


106


. The gear


106


is secured to an axially aligned tubular clutch member


107


. A tubular clutch member


108


has an end wall


109


with a non-circular hole


110


. A wrapped clutch spring


111


has a first spring portion


112


received by the outside surface of the clutch member


107


and a second spring portion


112


′ received by the inside surface of the clutch member


108


. A shaft


114


having a non-circular end portion


115


is received in the hole


110


so that the clutch member


108


and the shaft


114


rotate as a unit. The shaft


114


is secured to a disc


116


with three hook-shaped connectors


117


which couple to a drive member


118


for rewinding the ink ribbon IR in the ink ribbon cartridge


24


. The drive member


118


includes a rod


119


telescopically received in the shaft


114


. A spring


120


is also received in the shaft


114


and pushes on the rod


119


. The connectors


117


couple to the drive member


118


and enable the drive member


118


to shift against the force of the spring


120


when the cartridge is being installed into the printer. When the motor


95


is operated, the platen roll


38


is driven and the drive member


118


is driven through the spring clutch


113


comprised of the clutch members


107


and


108


and the clutch spring


111


. The clutch


113


assures that the proper tension is applied to the ink ribbon IR so that the ink ribbon is properly wound up in the cartridge.




The drive mechanism


94


is assembled using a frame member


121


secured to the housing


21


. A bracket


122


and the frame member


121


rotatably mount motor


95


, gears


97


and


99


,


98


and


104


, and


105


, the shaft


114


, and one of the bearing housings


103


′.




With reference to

FIG. 11

, there are shown housing sections generally indicated at


130


and


131


, the ink ribbon IR, a tubular core or spool C


1


on which the ink ribbon IR is wound into a roll R


1


and a tubular core or spool C


2


on which the used or spent ink ribbon is wound.




The cartridge housing


23


is comprised of the housing sections


130


and


131


. The housing section


130


has an axially extending shaft member


132


with a planar end surface


134


and an axial reduced-diameter end portion or projection


133


extending from the planar surface


134


. There is an axial hole


135


in the projection


133


. The shaft member


132


extends outwardly from a wall


136


of the housing section


130


. The housing section


131


has a shaft member


137


projecting from a wall or plate


138


of the housing section


131


. The shaft member


137


terminates at a surface


139


. A recess


140


in the shaft member


137


receives the projection


133


. The housing sections


130


and


131


can be suitably connected either permanently as by a permanent adhesive or releasably. A screw


141


is shown to pass through a hole


142


within the shaft member


137


and to be threadably received in the axial hole


135


in the projection


133


. As shown, the shaft members


132


and


137


are hollow.




A brake generally indicated at


143


is shown to comprise a tubular or sleeve member


144


having a frictional outer surface


145


. The sleeve member


144


has a central hole


145


′ for receiving the projection


133


. The sleeve member


144


is comprised of resilient closed-cell foam material and is positioned between surfaces


134


and


140


. The distance between the surfaces


134


and


140


in their assembled position is less than the length of the sleeve member


144


in its unassembled, unrestrained condition so that the sleeve member


144


is slightly compressed in the axial direction in the position shown in FIG.


13


. In that the sleeve member


144


is compressed, the sleeve member


144


is more dense than it is in its unrestrained condition prior to assembly. The shaft members


132


and


137


are stationary and the sleeve member


144


is held stationary on the projection


133


. The outer surface


145


of the sleeve


144


is in frictional contact with the inner surface


146


of the core C


1


. The core C


1


can be composed of either plastic or cardboard. This causes a braking force or drag to be applied to the core C


1


to maintain tension in the ink ribbon IR. The rotation of the platen roll


38


is sufficient, however, to cause the braking force exerted by the brake


143


to be overcome so that ink ribbon IR can be paid out or drawn from the ink ribbon supply roll.




The wall


136


also mounts a drive spindle


147


as best shown in FIG.


14


. The spindle


146


is rotatably received in an internally-stepped annular portion


148


. An internal flange


149


on the annular portion


148


is received between annular projections


150


and


151


on the spindle


147


. The drive spindle


147


is, thus, held captive in the annular portion


148


. A drive head


152


has a stud


153


which cooperates with any one of the grooves


118


′ in the drive member


118


. As the drive member


118


rotates, the drive head


152


is driven via stud


153


to drive the core C


2


. The drive spindle


147


has a drive lug


154


which engages a notch


155


(

FIG. 11

) in the core C


2


.




The core C


2


is supported both on the spindle


147


and on a shaft member


156


. Posts


157


and


158


secured to respective walls


136


and


138


can be connected by a screw


159


passing through a hole


160


in the post


158


and threadably received in the post


157


.




As best seen in

FIG. 15

, the housing sections


130


and


131


are positioned end-to-end. The upper housing member generally indicated at


161


is spaced upwardly from lower housing member


162


by an open space


163


. As seen in

FIG. 3

, the cartridge


24


is inserted onto the printer


20


by moving the cartridge


24


relative to the shelf


44


and the print head assembly


45


until the cartridge


24


has been slid to the position shown in FIG.


2


. The housing member


161


is tapered toward the center CE where the housing section


130


and


131


abut and the two abutting portions


130


′ and


131


′ which constitute the housing members


161


are flexible and resilient enough to deflect during assembly onto the printer


20


until arcuate portion


164


enters a recess


165


in the shelf


44


. Thus, as the cartridge


24


is slid onto the printer


20


and the print head assembly


45


and the shelf


44


enter the open space


163


, the arcuate surface


164


finally detents into the recess


165


to hold the cartridge


24


detented essentially in its operating position.




It is to be noted that the cartridge housing


23


has slots


166


which permit the guides


49


to clear the cartridge housing


23


. Upon such installation of the cartridge


24


, the mounting section


39


can be pivoted on posts


41


counterclockwise as seen in

FIG. 3

, and thereupon the mounting section


40


can be pivoted counterclockwise about posts


73


until the guides


49


locate on the bearing housing


103


′, as seen in FIG.


9


. This causes the print head


37


to be located precisely relative to the platen roll


38


.




Thereupon the assembly


46


can be moved to the generally vertical position (

FIG. 3

) so that the latching gripper


84


can engage the grip member


85


on the cartridge housing


23


. Thereupon the manually engageable member


90


can be pressed inwardly until the shaft


88


is in the overcenter position with respect to the centerline CL as shown in FIG.


8


.




When the assembly


46


is latched, the arm portions


44


′ which have notches


44




a


are urged by webs


130




c


and


131




c


against the stop


21




a


, thus locating the cartridge


24


in its operating position.




Other embodiments and modifications of this 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.



Claims
  • 1. A portable printer, comprising: a housing, space within the housing for roll of a composite label web having labels releasably adhered to a carrier web, a thermal print head for printing on labels, a platen roll cooperable with the print head, the print head and platen roll being above the label roll space, an ink ribbon cartridge including a cartridge housing having an upper housing member and a lower housing member spaced apart by an open space, the print head being movable between a printing position in cooperation with the platen roll and a loading and unloading position spaced from the platen roll, the print head being receivable through the open space between the upper and lower housing members, the cartridge further including an ink ribbon supply roll of an ink ribbon, the supply roll being received in one of the cartridge housing members, the ink ribbon extending into cooperation with the print head and being wound into a spent take-up roll in the other housing member, the platen roll being driven to advance the composite label web together with the ink ribbon, a clutch, an electric motor for driving the spent take-up via the clutch, and a battery disposed below the label roll space for powering the print head and the motor.
  • 2. A portable printer as defined in claim 1, wherein the clutch includes a spring.
  • 3. A portable printer as defined in claim 1, wherein the clutch is a wrapped spring clutch.
  • 4. A portable printer as defined in claim 1, wherein the platen roll is driven by the motor.
  • 5. A portable printer as defined in claim 1, wherein the housing includes a toggle mechanism for bringing the print head into pressure contact with the platen roll.
  • 6. A portable printer as defined in claim 1, wherein the print head is pivotably mounted to accommodate to the platen roll.
  • 7. A portable printer as defined in claim 1, wherein springs bias the print head against the platen roll, and a pin disposed between the springs for pivotably mounting the print head.
  • 8. A portable printer as defined in claim 1, including gearing between the motor and the clutch.
  • 9. A portable printer as defined in claim 1, wherein the clutch includes a wrapped spring clutch, wherein the platen roll is driven by the motor, and wherein the print head is pivotably mounted to accommodate to the platen roll.
  • 10. A portable printer as defined in claim 1, wherein the housing and the ink ribbon cartridge form a housing assembly, and means for releasably holding the housing assembly together.
CROSS-REFERENCE TO RELATED APPLICATION

This application is a division of application Ser. No. 09/069,377, filed Apr. 28, 1998, now U.S. Pat. No. 6,412,996, which is a division of Ser. No. 08/699,643, filed Aug. 19, 1996, now U.S. Pat. No. 5,772,341, which is a division of application Ser. No. 08/431,999, filed May 1, 1995, now U.S. Pat. No. 5,785,442, which is a division of application Ser. No. 08/137,660, filed Oct. 15, 1993, now abandoned. Application Ser. No. 08/320,884, filed Oct. 5, 1994, now U.S. Pat. No. 5,597,249 is a continuation-in-part of application Ser. No. 08/137,660, filed Oct. 15, 1993. Application Ser. No. 09/361,507, filed Jul. 27, 1999, now U.S. Pat. No. 6,386,774 is a division of application Ser. No. 09/069,377. Application Ser. No. 09/066,995, filed Apr. 27, 1998, now U.S. Pat. No. 5,938,351 is a division of application Ser. No. 08/431,999. Application Ser. No. 08/522,184 filed Aug. 31, 1995, now U.S. Pat. No. 5,588,756, is a continuation of application Ser. No. 08/137,660.

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