Tape printing apparatus and tape holding cases

Information

  • Patent Grant
  • 6332725
  • Patent Number
    6,332,725
  • Date Filed
    Thursday, September 7, 2000
    24 years ago
  • Date Issued
    Tuesday, December 25, 2001
    22 years ago
Abstract
The invention relates to a tape holding case housing a supply of image receiving tape and includes an angled surface to bend the surface of the tape approximately 90°, the angled surface being provided upstream of the printing position of the tape. The tape holding case also includes a casing that is designed to attach the tape holding case to an identically shaped tape holding case.
Description




TECHNICAL FIELD




The present invention relates to tape printing apparatus and also to tape holding cases for tape printing apparatus.




BACKGROUND ART




Known tape printing apparatus of the type with which the present invention is generally concerned are disclosed in EP-A-322918 and EP-A-322919 (Brother Kogyo Kabushiki Kaisha) and EP-A-267890 (Varitronics). These tape printing apparatus each include a cassette receiving bay for receiving a cassette or tape holding case. In EP-A-267890, the tape holding case houses an ink ribbon and a substrate tape, the latter comprising an upper image receiving layer secured to a backing layer by an adhesive. In EP-A-322918 and EP-A-322919, the tape holding case houses an ink ribbon, a transparent image receiving tape and a double-sided adhesive tape which is secured at one of its adhesive coated sides to the image receiving tape after printing and which has a backing layer peelable from its other adhesive coated side. With both these apparatus, the image transfer medium (ink ribbon) and the image receiving tape (substrate) are in the same cassette.




The present applicants have developed a different type of tape printing apparatus which is described for example in EP-A-578372, the contents of which are herein incorporated by reference. In this printing apparatus, the substrate tape is similar to that described in EP-A-267890 but is housed in its own tape holding case while the ink ribbon is similarly housed in its own tape holding case.




The known tape printing apparatus have input means, for example a keyboard, to allow the user to input an image to be printed. A display is generally also provided to display the input image or messages to the user. A cutting arrangement is provided to separate the image receiving tape on which an image has been printed from the supply of image receiving tape to thereby define a label.




In these known tape printing apparatus, the image receiving tape passes in overlap with the ink ribbon through a print zone consisting of a fixed print head and a platen against which the print head can be pressed to cause an image to transfer from the ink ribbon to the image receiving tape. This is usually done by thermal printing where the print head is heated and the heat causes ink from the ink ribbon to be transferred to the image receiving tape. This type of printing is known as thermal transfer printing. Alternatively, the print head may be in direct contact with a thermally sensitive image receiving tape whereby when the print head is heated, an image is printed directly on the image receiving tape. This type of printing is known as direct thermal printing.




In EP-A-661163 (Smith Corona), a tape printer is used in combination with a slot-in type cassette. The printhead is privotally fixed to the housing of the tool and interacts with a platen provided in the cassette. Since the printhead is spring biased towards the platen, it is capable of urging the cassette out of the printer, when the latches holding the cassette are released. The motor of this tape printer is located beside the cassette, but in a plane below the cassette, and is connected to the platen provided in the cassette by means of a gear train, parts of which being located below the cassette, as well.




EP-A-752321 (Esselte NV) discloses a tape printer in which the motor is located in approximately the same plane as the tape supply, however most parts of the gear train are located below the tape supply. A bevel gear is used for altering the direction of driving torque by 90°.




U.S. Pat. No. 5,615,960 (Alps) also discloses a tape printer in which the motor is located beside the tape supply, and most parts of the gear train are located below the tape supply.




SUMMARY OF THE INVENTION




According to the present invention, there is provided a tape printing apparatus having a platen for driving an image receiving tape through a printing zone, and a motor operatively connected to said platen by means of a gear train, wherein said motor and said gear train are approximately located within a plane in which a supply of said image receiving tape accomodated in said tape printing apparatus is arranged, and wherein a pair of gears of said gear train changes the direction of the rotation of the torque driving the platen by 90°, such that the rotational axis of said platen and a driving shaft of said motor include an angle of 90°.




It is thus proposed to position the motor and the gear train for driving the platen besides the location in which the tape cassette housing the image receiving tape is accomodated, instead of below the cassette location, as known from the prior art. Thus, a thinner machine can be built.




It is proposed that the rotational axis of said platen extends parallel to the plane in which the supply of said image receiving tape accomodated in said tape printing apparatus is arranged. Thus, the case according to this embodiment of the present invention is used in combination with the tape printer according an embodiment of the invention, in which a tape holding case allows due to a 90° bend to have a platen arranged orthogonal with respect to the supply of image receiving tape. This reduces the height required for the driving mechanism of the tape, and a thin tape printer is the advantageous result.




There can be provided a tape holding case for use with a tape printing apparatus having a print head for printing an image on an image receiving tape, and a surface, said print head and said surface having a first printing position in which said print head acts against said surface and a second non-printing position in which said print head and said surface are spaced apart, said tape holding case housing a supply of image receiving tape and having an interaction portion for separating the print head and the surface so that the print head and the surface are in the second position during insertion of the tape holding case in the tape printing apparatus, said interaction portion being arranged so that the print head and said surface are in the first position when the tape holding case is received in said tape printing apparatus.




By using the tape holding case to separate the print head and the surface, the tape printing apparatus can be simplified in that no mechanism is required to cause the print head to adopt the printing and non-printing positions. The cost of the tape printing apparatus can thereby be reduced.




It should be appreciated that in embodiments of the present invention, the surface against which the print head acts may be stationary at all times while the print head moves to cause the first and second positions to be adopted. Alternatively, the print head may be stationary whilst the surface moves to cause the first and second positions to be adopted. It is also possible that both print head and the surface be movable mounted. In the preferred embodiment of the present invention, the surface is substantially stationary while the print head is arranged to move.




Preferably, the print head and the surface are normally in the first position and the interaction portion is arranged during insertion to cause the print head and the surface to adopt the second position, said print head and surface being in the first position when the tape holding case is received in said tape printing apparatus. For example, the print head may be biased to the first position so that the interaction portion of the tape holding case acts against the biasing force to move the print head to the second position.




Preferably said interaction portion comprises a nose portion or control surface extending generally in the direction of insertion. Thus as the tape holding case is inserted, the interaction portion can cause the print head and the surface to adopt the second position.




Preferably said nose portion or control surface has a first surface shaped to gradually move the print head and/or the surface to cause the print head and surface to adopt the second position as the tape holding case is inserted and a second surface shaped to gradually move back the print head and/or the surface to cause the print head and surface to adopt the first position so that when the tape holding case is fully inserted in said tape printing apparatus, said print head and the surface are in the first position. The gradual movement of the print head and/or the surface reduces the possibility of any damage occurring to the print head.




Preferably, said first and second surfaces are angled in opposite directions. This permits the print head and/or surface to be eased from the first position to the second position and back to the first position.




Preferably a window is provided in said tape holding case adjacent said interaction portion, said image receiving tape being arranged to extend across said window, whereby when the tape holding case is received in said tape printing apparatus, the print head and the surface are in the first position with the print head on one side of the window and the surface against which the print head acts on the other side of the window.




Preferably, said print head is mounted on a support member and said interacting portion is arranged to contact said support member during insertion of said tape holding case. By contacting the support member rather than the print head itself, the possibility of damage occurring to the print head can be reduced.




Preferably, said interacting portion is arranged to contact said print head support member above and/or below the print head.




In one preferred embodiment of the invention, the interaction portion has guide means for guiding said image receiving tape. By using the interaction portion also to provide guide means for the image receiving tape, the risk of tape jamming can be reduced. Tape jamming may occur in conventional tape printing apparatus if the tape gets caught on for example the print head or the platen so that it can not be driven through the tape printing apparatus. This is a problem which may arise during insertion of the cassette in the cassette receiving bay.




In one preferred embodiment of the present invention, the guide means is provided by the nose portion. Thus, a single part of the tape holding case provides not only a means by which the print head and the associated surface can be separated but also guide means for the image receiving tape.




In some embodiments of the present invention, the tape holding case is provided with reinforcing means for reinforcing the interaction portion. In those embodiments where the interaction portion extends from the main body of the tape holding case, the interaction portion may be relatively weak and susceptible to damage. The reinforcing means reduces the likelihood of damage occurring to the interaction portion. These reinforcing means together with the interaction portion on the main body of the tape holding case may define a recess in which the print head or surface of the tape printing apparatus is receivable.




Preferably the tape holding case can be used in combination with a tape printing device.




In an embodiment of the invention, there can be provided a tape printing apparatus for printing an image on an image receiving tape and a tape holding case as described above, the tape printing apparatus comprising:




receiving means for receiving the tape holding case;




a print head for printing an image on said image receiving tape; and




a surface against which said print head acts during printing, said print head and said surface having a first printing position in which the print head acts against the surface, wherein when said tape holding case is inserted in said receiving means, said print head and/or said surface are moved by said interaction portion of the tape holding case so that the print head and surface have a second non-printing position in which said surface and said print head are spaced apart and when said tape holding case is received in said receiving means the print head and said surface are in said first position.




In an embodiment of the invention, there can be provided a tape printing apparatus for printing an image on image receiving tape, comprising:




means for receiving a supply of image receiving tape;




a print head for printing an image on said image receiving tape, said print head having a first position in which the print head acts against a surface to print an image on the image receiving tape, a second non-printing position and a third position intermediate said first and second positions; and




moving means arranged automatically to move said print head from said third position to said first position when said print head is at the third position.




By arranging the moving means automatically to move the print head from the third position to the first position when the print head is at the third position, the need to apply a large external force to cause the print head to adopt the required position is removed.




Preferably the moving means comprises biasing means. The biasing means may take the form of a spring. In a preferred embodiment of the present invention, the spring comprises a tension spring which is in a minimum state of tension when in the first and second positions but is in a greater state of tension when in the third position. The increased state of tension of the spring, when in the third position, causes the print head to be moved to the first position.




The print head may be mounted on a member, the member having a first portion which co-operates with a supply of image receiving tape as the supply of image receiving tape is inserted in the receiving means, whereby insertion of the supply of image receiving tape causes the print head to move from the second position to the third position. Thus, the insertion of the supply of image receiving tape will cause the print head to be moved from the second to the third position and the moving means will then cause the print head to be moved from the third position to the first position. Thus, embodiments of the invention may permit the displacement which the supply of image receiving tape needs to push the member through to be reduced as compared to other possible arrangements.




One advantage of embodiments of the present invention is that the final print head position (i.e. printing position or first position) is unrelated to the final position of the supply of image receiving tape. The final position of the print head should be accurately controlled and generally the number of components which affect it should be minimized.




The member may have a second portion arranged below the receiving means, the first portion being supported by said second portion and being in said receiving means.




The member may be substantially L-shaped with said print head being mounted on one arm of said L-shape, the first portion of said member being mounted on the other arm of the L-shape and said moving means being coupled to the member.




The first portion may have a sloping surface arranged to contact said supply of image receiving tape as it is inserted into the receiving means. Preferably, as the supply of image receiving tape is inserted, the supply of image receiving tape will contact the sloping surface which will gradually move as the supply of image receiving tape is inserted further into the cassette receiving bay. As the first portion moves, so does the part of the member on which the print head is mounted. The first portion may be arranged to push the supply of image receiving tape out of the receiving means as the print head is moved from the first position to the second position. Thus, the supply of image receiving tape may be easily removed from the receiving means, when required.




The print head preferably has a fourth position intermediate said first and second positions and the moving means is arranged automatically to move the print head from the fourth position to the second position, when said print head is at said fourth position. The fourth position may be intermediate the third and second positions.




Preferably, the moving means comprises an over center mechanism.




In an embodiment of the invention, there can be provided a tape printing apparatus for printing on image receiving tape comprising:




means for receiving a supply of image receiving tape;




a print head for printing an image on said image receiving tape;




a surface against which said print head co-operates to print an image on said receiving tape, said surface having a first position in which said surface acts against the print head and a second position in which the said surface is spaced apart from said print head, said surface further having a third position intermediate said first and second positions; and




moving means arranged automatically to move said surface from said third to said first position when said surface is at the third position.




In an embodiment of the invention, there is provided a tape holding case housing a supply of image receiving tape, wherein a bend of approximately 90° is provided in the tape upstream the printing position of said tape.




The tape holding case according to this embodiment offers several advantages. First of all, the printed image receiving tape emerges from the case in plane in which the printed image can be easily seen by the user, since this plane extends (due to the 90° bend) parallel to the plane defined by the case and the supply of image receiving tape within the case. Since the latter is generally located parallel to the keyboard and the display of the tape printer, the emerging printed tape can be easily seen and checked by the user regarding typing errors. The second advantage is associated with the sixth aspect of the present invention:




In an embodiment of the invention, there is provided a tape holding case housing a supply of image receiving tape, the tape holding case comprising a casing having means thereon for attaching the tape holding case to a second tape holding case. The proposed tape holding case is thus easily stackable.




In an embodiment of the invention, there can further be provided a tape printer in combination with a tape holding case with means for attaching it to a second tape holding case, wherein the tape printer has a zone for receiving the tape holding case, wherein the zone comprises elements interacting with the means of the tape holding case for attaching it to a second tape holding case.




Thus, the means for attaching the tape holding case to a second one can further serve to guide and hold the tape holding case in the respective tape printer.











BRIEF DESCRIPTION OF THE DRAWING




For a better understanding of the present invention and as to how the same may be carried into effect, reference will now be made by way of example to the accompanying drawings in which:





FIG. 1

shows a plan view showing the front of a tape printing apparatus;





FIGS. 2



a


to


2




c


show a schematic plan view of a first cassette receiving bay with a first cassette,

FIGS. 2



a


to


2




c


showing the three stages during the insertion of the cassette in the cassette receiving bay;





FIG. 3

shows a perspective view of the cassette shown in

FIGS. 2



a


to


c;







FIG. 4

shows a cross-sectional view of part of the cassette shown in

FIG. 3

along line A—A;





FIG. 5

shows a view from above of a portion of a third cassette receiving bay with no cassette present;





FIG. 6

is a cross-sectional view of part of the print head arm of

FIG. 5

along line VIII—VIII;





FIG. 7

shows a modified version of the cassette of

FIG. 3

;





FIG. 8

shows an enlarged view of the nose portion of the cassette of

FIG. 7

;





FIG. 9

is a simplified block diagram of control circuitry for controlling the tape printing apparatus;





FIG. 10

is a view showing a second tape printing apparatus;





FIG. 11

shows a top view of a cassette for use in the tape printing apparatus of

FIG. 10

;





FIG. 12

is a side view of the cassette of

FIG. 11

;





FIG. 13

is a perspective view of the cassette of

FIG. 11

;





FIGS. 14



a


to


14




e


show a schematic plan view of the cassette receiving slot of the apparatus of

FIG. 10

with the cassette of

FIG. 11

,

FIGS. 14



a


to


14




e


showing five stages during the insertion of the cassette in the cassette receiving slot;





FIG. 15

is a view showing the interior of the apparatus of

FIG. 10

;





FIG. 16

is a side view on the apparatus of

FIG. 15

;





FIG. 17

is a schematic plan view of a fifth cassette receiving bay in which a fifth cassette is inserted; and





FIG. 18

is a schematic plan view of a sixth cassette receiving bay with a sixth cassette inserted therein.











DESCRIPTION OF THE PREFERRED EMBODIMENTS





FIG. 1

shows a plan view of a tape printing apparatus


2


. The tape printing apparatus


2


comprises a keyboard


4


. The keyboard


4


has a plurality of data entry keys such as numbered, lettered and punctuation keys


6


for inputting data to be printed as a label and function keys


8


for editing the input data. The keyboard


4


may also have a print key


10


which is operated when it is desired that a label be printed. Additionally, an on/off key


12


is also provided for switching the tape printing apparatus on and off.




The tape printing apparatus


2


has a liquid crystal display (LCD)


14


which displays the data as it is entered. The display


14


allows the user to view all or part of the label to be printed which facilitates the editing of the label prior to its printing. Additionally, the display


14


is driven by a display driver


16


which can be seen in FIG.


9


.




Next to the keyboard


4


of the tape printing apparatus


2


, there is a cassette receiving bay


18


which is arranged to receive a cassette


20


housing a supply of image receiving tape


24


. The cassette receiving bay


18


is generally covered by a cassette bay lid


40


. Various embodiments of the cassette receiving bay


18


and the cassettes to be received therein will now be described in relation to

FIGS. 2

to


16


.




A first embodiment of the present invention will now be described with reference to

FIGS. 2



a


to


c


,


3


and


4


. These Figures show the key elements present in the cassette receiving bay


218


. In this embodiment, a print head


222


is mounted on a print head arm


226


which is pivotable about pivot point


228


. The pivot point


228


is arranged at one end of the print head arm


226


while the print head


222


is arranged at the other end thereof. The print head


222


acts against a rotatable platen


234


which is provided in the tape printing apparatus


2


. The print head


222


is biased in a direction towards the platen


234


. The platen


234


rotates in the direction of arrow F to drive the image receiving tape


24


through the tape printing apparatus


202


as an image is printed thereon.




In addition to a supply spool


232


of image receiving tape


24


, the cassette


220


includes a nose portion


240


which extends outwardly from the main body


243


of the cassette


220


. The cassette


220


is inserted into the cassette receiving bay


218


in the direction of arrow G, with the nose portion


240


forwardmost.




The nose portion


240


will now be described with reference to

FIGS. 2



a


to


c


as well as

FIGS. 3 and 4

. The nose portion


240


comprises a wall


242


extending parallel to the plane of the image receiving tape


24


. This wall


242


is effectively a continuation of one of the walls


245


of the main body


243


of the cassette


220


. A window


244


is defined in this wall


242


. The window


244


is positioned such that when the cassette


220


is in the position shown in

FIG. 2



c


, that is fully received in the cassette receiving bay


218


, the platen


234


is on one side the window


244


and the print head


222


is on the other side thereof. The window is also sufficiently large so that the print head


222


can be biased against the platen


234


through the window


244


so that an image is printed on the image receiving tape


224


and the image receiving tape


224


is also driven through the tape printing apparatus.




Also provided on the wall


242


of the nose portion


240


, which can be seen particularly clearly from

FIGS. 2



a


to


2




c


is a bulged portion


246


. The bulged portion


246


is provided directly adjacent the window


244


on the side of the window further from the spool


232


of image receiving tape


24


. The bulged portion


246


extends outwardly from the plane of the wall


242


both on the side of the wall


242


adjacent the print head


222


and the opposite side of the wall


242


. The purpose of this bulged portion


246


is to move the print head


222


away from the platen


234


when the cassette is first inserted (see

FIGS. 2



a


and


2




b


) and subsequently to allow the print head


222


to contact platen


234


when the cassette is fully inserted as shown in

FIG. 2



c.






On the side of the bulged portion


246


adjacent the print head


222


, two sloping sides


248


and


250


are provided. The two sloping sides


248


and


250


slope outwardly in a direction away from the print head


222


from a common point


232


. When the cassette


220


is first inserted in the cassette receiving bay


218


in the direction of arrow G, the print head


222


comes into contact with the first sloped surface


248


which slopes in a direction toward the print head


222


to point


232


. As the cassette


220


continues to be pushed into the cassette receiving bay


218


, the print head


222


is urged by the sloping surface


248


to pivot in a direction away from the platen


234


, about pivot point


228


. As the cassette


230


continues to be inserted, the print head


22


moves into contact with sloping surface


250


, which slopes from point


232


in a direction towards the platen


234


. Finally, when the cassette


220


is fully received in the cassette receiving bay


218


as shown in

FIG. 2



c


, the print head


222


is over the window


244


and contacts the image receiving tape


24


which extends there across. The print head


222


then acts against the platen


234


such that an image can be printed on the image receiving tape


24


and the image receiving tape


24


is driven through the tape printing apparatus. The reverse process occurs when the cassette


220


is removed from the cassette receiving bay


218


so that the print head


222


is moved out of contact with the platen


234


whilst the cassette


220


is being removed from the cassette receiving bay.




It should be appreciated that the bulged portion


246


will generally be arranged to contact the print arm


226


on which the print head is supported rather than the print head


222


itself to thereby avoid damaging the print head


222


. Thus, the bulged portion


246


contacts the print head arm


226


at a location above and/or below the print head


222


. The bulged portion


246


may therefore have a U-shaped cross-section such as shown schematically in FIG.


4


. As can be seen in this embodiment, the two arms


252


and


254


of the U-shaped cross-section contact the print head arm


226


above and below the print head


222


.




Reference will now be made to

FIGS. 7 and 8

which show a second embodiment, which is a modification of the embodiment shown in

FIGS. 2



a


to


c


,


3


and


4


. In the embodiment shown in

FIGS. 7 and 8

, the cassette


260


has a nose portion


262


. For clarity, the bulged portion has been omitted from the arrangement shown in

FIGS. 7 and 8

. However, the embodiment shown in

FIGS. 7 and 8

would incorporate the bulged portion discussed in relation to the previous embodiment. The nose portion


262


has, as can be clearly seen from

FIG. 8

, a boxed-shape cross-section


264


which encloses the image receiving tape


265


. As with the embodiment shown in

FIGS. 2

to


4


, the nose


262


is provided with a window


266


which permits the print head to act against the platen while an image is being printed on the image receiving tape. The box section


264


has the advantage that the risk of tape jams is considerably reduced.




The cassette


260


shown in

FIG. 7

has two triangular portions


268


and


270


extending between the nose portion


262


and the main body


272


of the cassette


260


. The triangular regions


268


and


270


are coplanar with the bottom surface of the cassette


260


and the top surface of the cassette


260


respectively. These triangular web portions


268


and


270


reinforce the nose portion to increase the resistance to damage of the nose portion


262


. The print head may be received in the enclosed space defined by the two triangular web portions


268


and


270


along with an inner wall portion of the nose portion


262


and the wall


274


of the cassette body


260


. Alternatively, the arrangement may be such that a platen could be accommodated in that recess. The web portions


268


and


270


may be of any suitable material such as plastics. The embodiment shown in

FIGS. 7 and 8

, may be modified so that no bulged portion is provided on the nose portion


262


. The nose portion


262


on its own may be sufficient to move apart the print head and the platen against which the print head cooperates. However, it is preferred that the bulged portion be present. This has the advantage that the nose portion does not contact the print head itself avoiding the possibility that the print head might be damaged.




Reference will now be made to

FIG. 5

which shows a third embodiment of the present invention. In

FIG. 5

, the position of the print head arm


326


, when closed is shown in solid lines while the position of the print head arm


326


when in the open position is shown in dotted lines. The print head arm


326


comprises a first portion


327


and a second portion


328


. The print head arm portions


327


and


328


together define an L-shaped print head arm


326


. The print head arm


326


is pivotable about pivot point


330


which is arranged at a corner region


331


of the L-shaped print head arm


326


. The second print head arm portion


328


carries the print head


322


itself. The print head is arranged to cooperate with a rotatable platen


334


.




A print head spring


336


is attached at one end to a spring anchor point


338


and at the other end to an attachment point


340


on the print head arm


326


. The spring


336


is an extension spring which is arranged to be held under tension. It should be appreciated that the first portion


327


of the print head arm


326


will in use be arranged below the floor of the cassette receiving bay. A wedge


342


is arranged on the first portion


327


of the print head arm


326


. This wedge


342


is arranged to extend above the floor of the cassette receiving bay and is shown in more detail in FIG.


6


.




When the cassette receiving bay is empty, the print head arm


326


is in the position shown in dotted lines in

FIG. 5. A

cassette is arranged to be inserted into the cassette receiving bay in the downward direction, that is in a direction towards the plane of the page containing FIG.


5


. As the cassette is inserted, it engages the wedge, which can be seen in FIG.


6


. As the cassette is moved downwardly, the bottom edge of the cassette engages the wedge


342


at location


343


gradually moving the wedge and hence the first portion


327


of the print head arm


326


in the direction of arrow H. As the print head arm


326


is pivotably movable about pivot point


330


, the second portion


328


of the print head arm


326


moves in the direction of arrow I towards the rotatable platen


334


. As the second part


328


of the print head arm


326


moves towards the rotatable platen


334


, the length of the spring


336


extends slightly until it reaches a maximum length when the print head arm


326


is in a position halfway between those two positions illustrated in FIG.


5


. Once the print head arm has passed this halfway point, the tension in the spring


336


urges the spring to the position shown in solid lines in

FIG. 5

so that the print head


322


is in contact with the rotatable platen


334


.




In order to remove the cassette, the user moves the print head arm


326


from the position shown in solid lines in

FIG. 5

to the position shown in dotted lines. As the print head arm


326


moves towards the position shown in dotted lines, the wedge portion


324


acts against the cassette to push it up out of the cassette receiving bay. The print head arm


326


may be operated by turning a lever or pressing a button.




Thus, the print head


322


is mounted on a print head arm


326


on which the cassette acts on, via the wedge


342


, as the cassette is inserted. The spring


336


is arranged to pull the print head


322


into the printing position in which the print head


322


acts against the platen once cassette insertion has caused the print head to move a relatively short distance from the open position (shown in dotted lines). This has the advantage that the cassette itself does not have to oppose the print head force.




Reference will now be made to

FIG. 9

which generally shows a simplified block diagram of control circuitry which can be used with any of the described embodiments. A drive roller


30


(see

FIGS. 15 and 16

) and/or the rotatable platen


234


are driven by the motor


42


so that it rotates to drive the image receiving tape


24


in a direction which is parallel to the lengthwise extent of the image receiving tape


24


through a print zone


62


defined between the print head


22


,


122


or


222


and the platen


34


or


234


respectively. In this way, an image can be printed on the image receiving tape


24


as it passes through the print zone


62


.




The cutting arrangements described in relation to the fifth and sixth embodiments can be incorporated in any of the embodiments described hereinbefore.




The print head


22


,


122


,


222


is a thermal print head comprising a column of a plurality of printing elements. The print head is preferably only one element wide and the column extends in a direction perpendicular to the lengthwise extent of the image receiving tape


24


. The height of the column of printing elements is preferably equal to the width of the image receiving tape to be used with the tape printing apparatus


2


. With embodiments of this invention, where more than one width of image receiving tape


24


is used, the print head column will generally have a height suitable for printing on the largest width of tape


24


. An image is printed on the image receiving tape


24


column by column by the print head


22


,


122


, or


222


.




The basic control circuitry illustrated in

FIG. 9

comprises a microprocessor chip


64


. The microprocessor chip


64


has a read only memory (ROM)


66


, a microprocessor


68


and random access memory capacity


70


indicated diagrammatically by RAM. The microprocessor


68


is controlled by programming stored in the ROM


66


and when so controlled acts as a controller. The microprocessor chip


64


is connected to receive label data input to and from the keyboard


4


. The microprocessor chip output is connected to drive the display


14


via the display driver chip


16


to display a label to be printed (or a part thereof and/or a message or instructions for the user. It should be appreciated that the display driver


16


may form part of the microprocessor chip


64


.




The microprocessor chip


64


also outputs data to drive the print head


22


,


122


,


222


to print an image on the receiving tape


24


to form the label. The microprocessor chip


64


also controls the motor


42


for driving the image receiving tape


24


through the tape printing apparatus. The motor


42


may be a dc motor which continuously drives the image receiving tape


24


through the print zone


62


during printing. Alternatively, the motor


42


may be a stepper motor. In this situation, the drive roller


30


or platen


234


rotates stepwise to drive the image receiving tape


24


in steps through the print zone


62


during the printing operation.




The microprocessor chip


64


may also control the cutting arrangement


50


or blade


124


to allow lengths of image receiving tape to be cut off after an image has been printed thereon. The cutting arrangement


50


or blade


124


may alternatively be manually operated.




A fourth embodiment of the invention is shown in

FIGS. 10

to


16


. The tape printer


2


according to this embodiment is generally brick shaped, and has on its upper end a tape cassette


443


inserted into a corresponding slot, the latter being shown more detailed in

FIGS. 14



a-e


. A keyboard on the front left side of the tape printer is schematically indicated with reference numeral


4


, although the keys as such are for reasons of simplification not shown. The printing mechanism is included into the top part of the tape printer, while the batteries providing the necessary electrical energy are situated inside the lower part of the housing covered with the keyboard


4


. The printed tape emerges from an outlet


426


out of the housing of the tape printer


2


. A display


14


is provided above the keyboard


4


, such that a user can easily see and check his or her inputted data. The cassette


443


has an additional feature (which is not provided in the tools according to the remaining embodiments of the present invention); it provides a bend of 90° in the tape before printing. This will be shown more clearly in

FIGS. 11-13

. Hence the tape


24


emerges in the plane of the display


14


out of the outlet


426


of the tape printer


2


, thus making it easier for the user to control the printed image.





FIG. 11

shows a view into the cassette


443


of the fourth embodiment. It houses a supply spool


32


of image receiving tape


24


. The image receiving tape


24


is guided from the supply spool around a pin


401


extending orthogonally to the plane of the side wall of the cassette


443


on which the supply spool


32


lies. The pin


401


is located at the lower left corner of the cassette


443


, and deflects the tape for 90°, such that it extends rightwards in

FIG. 11

, after it has passed the pin


401


. Additionally to the deflection performed by pin


401


, the tape is downstream the pin


401


lying on a angled, triangular surface


410


, which encloses an angle (in this embodiment of 45°) with the length axis of the pin


401


. Consequently, the tape


24


is bent by pin


401


and surface


410


such that the image receiving tape


24


extends at the right, downstream end (which is indicated by the dotted line


470


) of the angled surface


410


in the plane of the drawing. Thus, the angled surface is designed such that its left end adjacent the pin


401


is extending orthogonally to the plane of

FIG. 11

, and that its right end


470


extends parallel to the plane of FIG.


11


. The right end


470


of surface


410


is located close to the left edge of a window


466


in the housing of the cassette


443


. The window


466


is indicated with two parallel dotted lines and is required in order to let a print head


422


and a platen


434


interact in order to print upon the image receiving tape


24


. Consequently, the window


466


has the same function as the window


244


in FIG.


3


and window


266


in FIG.


7


. At the right end of the cassette


443


an outlet


465


is provided, through which the image receiving tape


24


emerges after it has passed the printing location at window


466


. The outlet


465


is shaped similarly to the nose portion


262


shown in FIG.


8


. Thus, it has a box-shaped cross section enclosing the image receiving tape


24


. This cross section is obtained by a bar


407


extending parallel to the plane of

FIG. 11

, but having an appropriate distance to the adjacent bottom wall


472


(see

FIG. 12

) of the cassette


443


. A cutting mechanism (not shown) for separating the printed image receiving tape is located downstream the outlet


465


.




On the bottom edge (in

FIG. 11

) of the cassette


443


, a surface


446


having a lengthwise extension in the direction in which the cassette


443


is inserted into the tape printer


2


is provided. This surface


446


serves to control the position of the printhead


422


with respect to the platen


434


when the cassette


443


is inserted into the tape printer


2


. This will be shown more detailed with reference to

FIGS. 14



a-




14




e.






The housing of the cassette


443


consists essentially of two moulded parts, one of which being a bottom wall


472


, and the other one being a cover wall


473


, as indicated in FIG.


12


. These walls enclose the tape supply spool


32


, pin


401


, and further parts.

FIG. 11

shows a view onto the cover wall


473


. It should be noted that the surface


446


can be provided either on the bottom wall


472


, or on the cover wall


473


, like in the embodiment shown in

FIGS. 11-13

.




The cassette


443


is provided on its bottom wall


472


with an upstanding projection


403


having a rectangular cross section and extending parallel to the lengthwise direction of the surface


446


for controlling the printhead position. This can best be seen in

FIG. 12

showing a side view onto the cassette


443


of FIG.


11


. The upstanding projection


403


is located at about ⅓ of the height of the cassette


443


. In the cover wall


473


of the housing of the cassette


443


, a recess


404


is provided which extends parallel to the upstanding projection


103


, and is located at the same height. The cross section of the recess


404


corresponds to the cross section of the upstanding portion


403


. The purpose of upstanding projection


103


and recess


104


is twofold: On one hand, they interact with corresponding parts of the cassette receiving slot


475


in order to provide a guidance for the cassette


443


when it is inserted. On the other hand, they allow to stack two or more cassettes


443


together, without any additional elements, thus making storage of cassettes simpler.





FIG. 13

shows a perspective view of the cassette


443


. It is apparent that the distance between surface


446


and the bottom wall


472


varies with increasing distance from the front edge of the cassette


443


which it is inserted in the first place into the tape printer


2


. This is necessary in order to control the position of printhead


422


and platen


434


appropriately.





FIGS. 14



a-e


illustrate how cassette


443


and tape printer


2


interact during insertion of the cassette. As shown in

FIG. 14



a


, a slot


475


is provided in the tape printer


2


into which the cassette is to be inserted for printing upon the image receiving tape


24


. Within the slot


475


, a platen


434


and a print head


422


are provided. The platen


434


is driven by a motor (not shown) and located within a recess in a wall of the slot


475


. The recess protects the platen


434


against unwanted damages. The printhead


422


is mounted on a printhead holder


468


, which is pivotally supported on a pin


469


, and spring biased towards the platen


434


. When no cassette is inserted, the printhead and the platen are thus in touch with each other. A sensing pin


467


is provided on the printhead holder


468


for interacting with the surface


446


of the cassette


443


, and controlling the position of the printhead


422


. In the described embodiment, the print head


422


is a thermal print head, but it could be an ink jet printhead, as well. The axis of the printing elements of the printhead


422


extends parallel to the axis of the platen


434


, and within the plane of the image receiving tape


24


, when it is located at the window


466


, thus enclosing an angle of 90° with the center axis of the tape supply spool


32


.




In

FIG. 14



a


, the cassette


443


has just been inserted into the tape printer


2


. Thus, the cassette


443


is only shifted some millimeters into the slot


475


, and the sensing pin


467


does not touch the surface


446


of the cassette


443


. Consequently, the printhead holder


468


is in its rest position, wherein the printhead


422


is touching the platen


434


.




In

FIG. 14



b


, the cassette


443


is moved somewhat deeper into the slot


475


. The sensing pin


467


is in touch with the surface


446


of the cassette


443


. It is apparent that the position of the sensing pin


467


depends on the distance between the point where it touches the surface


446


and the bottom wall


472


of the cassette housing. With other words, the sensing pin


467


scans the shape of the surface


446


. Since the surface


446


(its cross section shown in

FIGS. 14



a-e


) is approximately sinusoidally curved, the surface


446


has caused the sensing pin


467


to move downward, and thus to rotate the printhead holder


468


clockwise. Consequently, the printhead


422


is separated from the platen


434


. This is necessary for introducing the image receiving tape


24


between printhead


422


and platen


434


.




In

FIG. 14



c


, the sensing pin


467


is located near the point of the surface


446


having the largest distance between surface


446


and bottom wall


472


, ie. the sensing pin is near its peak position. The printhead holder


468


has consequently rotated further such that the printhead


422


is as far as possible away from the platen


434


, and nearly touches the wall of the slot


475


opposite to the platen


434


. It is thus easily possible to insert the image receiving tape


24


between platen


434


and printhead


422


.




In

FIG. 14



d


, the cassette


443


is even further shifted into the slot


475


. Since the distance between the surface


446


and the bottom wall


475


is now decreased, the sensing pin


467


has caused the (biased) printhead holder


468


to rotate counterclockwise such that the printhead


422


has moved towards the platen


434


.





FIG. 14



e


illustrates the final, operative position of the cassette


443


. The printhead


422


cooperates with the platen


434


through the window


466


in order to print upon the image receiving tape


24


. The printhead holder


468


further arrests the cassette


443


in the operative position since it engages with the window


466


. When the cassette


443


is moved out of the slot


475


, the printhead holder


468


moves in the reverse direction through the positions indicated in

FIGS. 14



a-e


. The cassette


443


thus provides a surface


446


which interacts with the printing mechanism of the tape printer


2


for allowing easy insertion and removal of the cassette. It should be noted that it would be possible to provide a spring for biasing the printhead


422


towards the platen


434


with a sufficient strong force, such that the user only needs to shift the cassette


443


such far that the sensing pin


467


gets into the peak position (

FIG. 14



c


), and can then release it, while the spring moves the cassette into the operative position (

FIG. 14



e


) or out of the tape printer (

FIG. 14



a


). Thus, an over center mechanism as shown in

FIGS. 5 and 6

could be provided in the fourth embodiment of the invention, as well.





FIGS. 15 and 16

illustrate another advantage associated with the 90° bend in the image receiving tape


24


within the cassette


443


before (ie. upstream) the printing position. This 90° bend allows to dispense with a gear train for driving the platen


434


behind the cassette


443


. Thus, a thinner tape printer can be achieved. As shown in

FIG. 15 and 16

, the motor


42


is located below the cassette slot


475


, and within the plane defined by the supply


32


of image receiving tape, and by the cassette


443


housing the supply


32


. A gear train


480


is provided for driving the platen


434


, wherein the gears are situated below the cassette


443


, ie. between motor


42


and platen


434


, and approximately lie within the same plane as the motor


42


. Since the driving shaft of the motor


42


extends horizontally in

FIGS. 15 and 16

, and the platen


434


rotates around a vertically extending axis, there is a part of the gear train, ie. a pair of gears, provided which alters the rotation direction for 90°. The driving shaft of the motor


42


and the rotational axis of the platen


434


extend parallel to the plane defined by the supply


32


of image receiving tape, ie. within the plane of FIG.


15


.

FIGS. 15 and 16

further show the position of batteries


481


in the lower part of the tape printer


2


.




Reference will now be made to

FIG. 17

which shows a fifth embodiment of a cassette receiving bay


18


with the lid


40


removed. The cassette receiving bay


18


has a thermal print head


22


for printing an image onto a supply of image receiving tape


24


. As will be described in more detail hereinafter, the print head


22


is mounted on a printhead arm


26


which is pivotable about pivot point


28


. A drive roller


30


is driven by a dc motor


42


(see

FIG. 9

) and rotates in the direction of arrow A in order to drive the image receiving tape


24


through the tape printing apparatus. The cassette


20


housing the supply of image receiving tape


24


is received in the cassette receiving bay


18


. The cassette


20


holds a supply spool


32


of image receiving tape


24


. The image receiving tape


24


may comprise an upper layer for receiving a printed image on one of its surfaces and its other surface coated with an adhesive layer to which is secured a releasable backing layer. The image receiving tape


24


is guided by a guide mechanism (not shown) through the cassette


20


, out of the cassette


20


through an outlet O, past the print head


22


to a cutting location C′. The image receiving tape


24


comprises a thermally sensitive material on which an image is printed when in contact with activated or heated elements of the thermal print head. No ink ribbon is required in order to print an image on the thermally sensitive image receiving tape


24


. Some of the embodiments described herein may be modified so that ink ribbon is also provided in the cassette. In these embodiments the image receiving tape may not be thermally sensitive. An image would then be printed on the image receiving tape via the ink ribbon.




A cutting arrangement


50


is provided at the cutting location C′. The cutting arrangement


50


comprises a blade support member


52


which carries a blade


54


. The cutting arrangement


50


also comprises an anvil


56


against which the blade


54


acts. In this way, a portion of the image receiving tape


24


on which an image has been printed can be separated from the supply of image receiving tape to thereby define a label.




The cassette


20


has a platen


34


in the form of, for example, a flat substantially planar resilient pad, mounted on the outside of the housing


35


of the cassette


20


. In particular, the housing


35


of the cassette


20


has a side wall


37


, parallel to the axis of rotation of the supply spool


32


, which confronts the print head


22


. The platen


34


is provided on the surface of this wall


37


. This platen


34


may be of any suitable material such as rubber or the like. The platen


34


is arranged so that in use the platen


34


comes into contact with the print head


22


with the image receiving tape


24


therebetween. The print head


22


can then act against the platen


34


during printing to provide a good quality image.




An idler roller


36


is also provided in the cassette


20


which cooperates with the drive roller


30


in the tape printing apparatus to drive the image receiving tape


24


through the tape printing apparatus


2


. The idler roller


36


is partially housed in the cassette


20


and partially extends outwardly of the side wall


37


on which the platen


34


is arranged. As the drive roller


30


rotates in the direction of arrow A, the drive roller


30


causes the idler roller


36


to rotate in the direction of arrow B.




Both the print head arm


26


and the drive roller


30


are resiliently mounted so as to be biased in a direction towards the cassette


20


. In particular, the print head arm


26


is arranged to urge the print head


22


against the platen


34


when the cassette


20


is inserted in the cassette receiving bay


18


. Likewise, the drive roller


30


is biased so as to be urged against the idler roller


36


so that the image receiving tape


24


can be driven by the rotation of the drive roller


30


through the tape printing apparatus


2


.




The cassette


20


is inserted in the cassette receiving bay


18


in the direction of arrow C. The platen


34


on the side wall


37


of the cassette


20


comes into contact with the biased print head


22


, with the image receiving tape


24


being between the platen


34


and the print head


22


. Good contact between the print head


22


and the platen


34


is ensured by the biasing of the print head


22


in the direction towards the platen


34


. The idler roller


36


also comes into contact with the drive roller


30


, again with the image receiving tape


24


therebetween. As a result of the biasing of the drive roller


30


, the drive roller


30


is urged against the idler roller


36


so that the image receiving tape


24


can be driven through the tape printing apparatus


2


as a result of the rotation of the idler roller


36


and the drive roller


30


.




The cassette


20


is retained in place by clips


38


. The clips


38


are provided in the cassette receiving bay


18


and clip over the cassette


20


to retain it in place. These clips


38


may be manually operated by the user. In one preferred embodiment, the clips


38


automatically engage the cassette


20


, when the cassette


20


is inserted into the cassette receiving bay


18


. To remove the cassette


20


, the user manually moves the clips


38


out of place. It should be appreciated that any suitable clip or catch member can be used to retain the cassette


20


in place. The clips


38


are arranged to engage the two corners


41


and


43


of the cassette


20


which are further from the print head


26


and the drive roller


30


. The cassette


20


could alternatively be released from the clips


38


by activating a button or lever provided externally of the cassette receiving bay


18


.




In a modification to this embodiment, the cassette bay lid


40


, which may be hinged or sliding, is arranged to push the cassette


20


into the operative position as the lid


40


is closed. Members which protrude from the lid


40


into the cassette receiving bay


18


may be used to push the cassette into position. The lid


40


may then itself latch to retain the lid closed and the cassette


20


in position.




Reference will now be made to

FIG. 18

which shows a modification to the embodiment shown in FIG.


17


. Like parts are indicated by like reference numerals and accordingly only those parts which are different will be described. The cassette


120


is provided with a planar drive surface


136


on the same wall


137


of the cassette


120


on which the platen


34


is defined. This drive surface


136


is of a low friction material and replaces the idler roller


36


of the first embodiment. The drive surface


136


cooperates with the drive roller


30


which is biased towards the drive surface


136


to drive the image receiving tape


24


through the tape printing apparatus.




The cassette


120


is provided with a slot


122


. When the cassette is in the cassette receiving bay


118


, a cutter blade


124


is arranged to move into the slot


122


during a cutting operation to thereby separate the image receiving tape


24


on which an image has been printed from the supply


32


of image receiving tape. The cut portion of image receiving tape


24


defines a label and exits the cassette receiving bay


118


through slot


126


.




The cassette receiving bay


118


is additionally provided with a pair of arms


138


for retaining the cassette


120


in position. The arms


138


are made of a resilient material and are biased to adopt the position shown in FIG.


18


. The free end


139


of each arm has an angled surface


140


. As the cassette


120


is inserted into the cassette receiving bay


118


in the direction of arrow D, the corners


121


of the cassette


120


adjacent the wall


137


supporting the platen


34


and the drive surface


123


engage the angled surfaces


140


and urge the arms


138


away from each other. The arms


138


are held by the sides


144


of the cassette


120


in this position until the cassette


120


is fully inserted, and the other two corners


141


of the cassette


120


have passed the angled surfaces


140


. The arms


138


move in a direction towards one another so as to be once more in the position shown in FIG.


18


. As mentioned hereinbefore the arms


138


are biased to the position shown in FIG.


18


. The other two corners


141


of the cassette


120


are accommodated in corners


142


defined at the end of each arm


138


between the free end


139


and a main portion


143


of each arm


138


. The cassette


120


is thereby retained in position by the arms


138


with the print head


22


biased against the platen


34


and the drive roller


30


biased against the drive surface


136


.




When the cassette


120


is fully received in the cassette receiving bay


118


, the side walls


144


of the cassette


120


, perpendicular to the wall


137


on which the platen


34


and the drive surface


121


are supported, are in contact with protrusions


146


defined on the main portions


143


of the arms


138


. The combination of the protrusions


146


together with the corners


142


of the arms


138


retains the cassette


120


in the cassette receiving bay


118


and prevents significant movement of the cassette


120


.




When the cassette


120


is to be removed from the cassette receiving bay


118


, the arms


138


are pushed together by applying an inward pressure at area


135


and in the direction indicated by arrows E. This causes the arms


138


to move about a pivot region defined by the protrusions


146


. The free ends


139


of the arms


138


therefore move in a direction away from each other and the cassette


120


can be removed from the cassette receiving bay


118


as the arms


138


no longer retain the cassette


120


in position.




By using a flat platen, as in the fifth and sixth embodiments, which cooperates with the print head rather than a curved roller, as in the prior art, the costs of manufacturing the tape printing apparatus can be reduced. This is because the curved nature of the prior art roller surface imposes tight restrictions on the allowable position of the print line relative to the roller platen. In other words, there is an optimum line on the platen at which contact should be made with the print head. In contrast, with a flat platen, the area of the platen on which contact can be made with the print head to achieve good quality printing is much larger. This leads to lower production costs as the relative position of the print head and platen is not as critical as in the prior art.




The above embodiments may be modified so that the cassette receiving bay lid


40


is replaced by a much smaller opening through which the cassette is inserted in the direction of arrow C or arrow D. In particular the cassette is inserted in a direction parallel to the planar surfaces defining the upper and lower surfaces of the cassette. The provision of a relatively large lid cover over the cassette receiving bay may has the disadvantages that the appearance of the product may be compromised and that the large lid is a weak point if the tape printing apparatus is dropped. The use of the relatively small opening may overcome these disadvantages. In particular, the cassette receiving bay may have an opening corresponding to the maximum cross-sectional dimension of the cassette. In contrast, the prior art arrangements require a cassette bay opening at least as large as the maximum planar dimension of the cassette.




The above described embodiments may have the advantage that tape jamming resulting from the tape catching on the printing mechanism can be reduced. In particular, in the known arrangements, the tape has to be dropped down between a platen and a print head which are both provided by the tape printing apparatus. During insertion the tape may snag on the edge of the print head or the platen which may lead to subsequent jamming. In the first and second embodiments, the platen is provided on the cassette. Accordingly, the cassette can be inserted in the direction of arrow C or arrow D and the tape is not dropped down into position as in the known arrangements. The tape is thus less likely to snag leading to fewer tape jams.



Claims
  • 1. A tape holding case (443) housing a supply (32) of image receiving tape (24) comprising: means to bend the surface of the tape approximately 90° without changing the direction of the tape movement, the tape having a printing position, the means being provided upstream of the printing position of the tape.
  • 2. A tape holding case (443) according to claim 1, wherein the means for bending the tape (24) comprises an angled surface (410).
  • 3. A tape holding case (443) according to claim 2, wherein the angled surface is fixed.
  • 4. A tape holding case (443) according to claim 1 further comprising:means to bend the direction of the tape approximately 90°, the means being provided upstream of the means to bend the surface of the tape.
  • 5. A tape holding case (443) according to claim 4, wherein the means to bend the direction of the tape is provided adjacent the means to bend the surface of the tape.
  • 6. A tape holding case (443) according to claim 4, wherein the means to bend the direction of the tape comprises a pin.
  • 7. A tape holding case (443) according to claim 1 further comprising a tape spool configured to supply the tape, and a cutting location in which the tape is to be cut.
  • 8. A tape holding case (443) housing a supply (32) of image receiving tape (24) comprising:a tape spool configured to supply the tape; a cutting location in which the tape is to be cut; and means to bend the surface of the tape approximately 90° only once as the tape moves from the spool to the cutting location without changing the direction of the tape movement.
  • 9. A tape holding case (443) according to claim 8, wherein an angled surface (410) is provided for bending the tape (24).
  • 10. A tape holding case (443) according to claim 9, wherein the angled surface (410) is fixed.
Priority Claims (2)
Number Date Country Kind
9621379 Oct 1996 GB
9717933 Aug 1997 GB
Parent Case Info

This application is a division of application Ser. No. 09/180,502, filed Nov. 12, 1998 now U.S. Pat. No. 6,152,623, which is a 371 of PCT/EP97/05065, filed Sep. 16, 1999.

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