Printing apparatus

A tape printer for printing an image on an image receiving medium including a tape receiving portion for receiving a supply of image receiving medium on which an image is to be printed; a printing mechanism arranged to print an image on said medium; a cutting mechanism for cutting off a portion of said medium, wherein the cutting mechanism comprises a cutter guide track defining a predetermined path for guiding a cutter of the cutting mechanism, wherein different parts of the cutter intersect the medium as the cutter moves to cut off said portion.

REFERENCE TO RELATED APPLICATIONS

This is the United States National Phase under 35 U.S.C. §371 of international application no. PCT/182007/004456, having an international filing date of Dec. 20, 2007, and claims priority to United Kingdom patent application GB 0625815.6, filed Dec. 22, 2006, and European patent application EP 07253954.7, filed Oct. 5, 2007.

FIELD OF THE DISCLOSURE

The present disclosure relates to a tape printing apparatus and to a method of printing on a tape to form a label. In particular, the present disclosure relates to a tape printing apparatus having a cutter arranged to cut the tape, so that the tape forms a label.

BACKGROUND OF THE DISCLOSURE

Tape printers are known which use a supply of tape, housed in a cassette received in the tape printer. The tape comprises an image receiving layer and a backing layer which are secured to one another via an adhesive layer. After an image has been printed onto the image receiving layer, the backing layer can be removed allowing the image receiving layer to be secured to an object using the adhesive layer. Such tape printers include a cutting mechanism for cutting off a portion of the tape after an image has been printed onto the image receiving layer so that the portion of tape can be used as a label. For this purpose the cutting mechanism includes a blade which is intended to cut through all the layers of the tape.

The cutting mechanism in these known tape printers can be operated by the user manually. Alternatively the cutting mechanism may be driven by a motor in the tape printer. Some examples of automatic cutting mechanisms are described in EP-A-534799, EPA-929402, EP-A-764542 and U.S. Pat. No. 5,599,119. An embodiment of an automatic cutter is incorporated into the DYMO PC-10 Electronic Label maker.

A relatively large force needs to be applied by the blade on the tape in order to perform the cutting operation. Over time, continual cutting operations cause the blade to wear. This is disadvantageous since it is not desirable for a user of the printer to change the blade during the lifetime of the printer. Furthermore the force required to cut the tape can often distort the tape and in some cases cause the tape to move during the cutting operation. As the blade wears the tape is more likely to distort during the cutting operation. Distortion of the tape during cutting may result in a label having a cut edge that is not smooth.

The force required to cut the tape may also cause the position of a tape cassette housing the tape to displace during cutting. This causes further problems such as incomplete cutting of the tape, and misalignment of the printed image on the tape in subsequent printing operations.

It is therefore an aim of the present disclosure to overcome the disadvantages discussed above.

SUMMARY OF THE DISCLOSURE

According to a first aspect of the present disclosure there is provided a tape printer for printing an image on an image receiving medium comprising: a tape receiving portion for receiving a supply of image receiving medium on which an image is to be printed; a printing mechanism arranged to print an image on said medium; a cutting mechanism for cutting off a portion of said medium, wherein the cutting mechanism comprises a cutter guide track defining a predetermined path for guiding a cutter of the cutting mechanism, wherein different parts of the cutter intersect the medium as the cutter moves to cut off said portion.

According to a second aspect of the present disclosure there is provided a method of cutting a portion of an image receiving medium to form a label comprising; guiding a cutter to move along a guide track defining a predetermined path whereby different parts of the cutter intersect the image receiving medium as the cutter moves as the cutter moves to cut off said portion.

According to a third aspect of the present disclosure there is provided a printer for printing an image on an image receiving medium comprising: a receiving portion for receiving a supply of image receiving medium on which an image is to be printed; a printing mechanism arranged to print an image on said medium; a cutting mechanism for cutting off a portion of said medium, wherein the cutting mechanism comprises a cutter guide track defining a predetermined path for guiding a cutter of the cutting mechanism, wherein different parts of the cutter intersect the medium as the cutter moves to cut off said portion.

According to a fourth aspect of the present disclosure there is provided a tape printer for printing an image on an image receiving medium comprising: a tape receiving portion for receiving a supply of image receiving medium on which an image is to be printed; a printing mechanism arranged to print an image on said medium; and a cutting mechanism for cutting off a portion of said medium, wherein the cutting mechanism comprises a cutter guide track defining a predetermined path for guiding a cutter of the cutting mechanism during a cutting cycle, wherein during a first portion of the cutting cycle the guide track is arranged to guide the cutter to intersect a plane of the medium such that a portion of the medium is cut off, and wherein during a second portion of the cycle the guide track is arranged to guide the cutter to return to a home position such that the cutter does not intersect the plane of the medium.

According to a fifth aspect of the present disclosure there is provided a method of cutting an image receiving medium to form a label comprising; guiding a cutter to move along a predetermined path during a cutting cycle, wherein during a first portion of the cutting cycle the guide track is arranged to guide the cutter to intersect a plane of the medium such that a portion of the medium is cut off, and wherein during a second portion of the cycle the guide track is arranged to guide the cutter to return to a home position such that the cutter does not intersect the plane of the medium.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE DISCLOSURE

FIG. 11shows a schematic diagram of a tape printing apparatus100according to an embodiment of the present disclosure. The tape printing apparatus comprises a keyboard101and a cassette receiving bay102.

The cassette receiving bay102houses a cassette containing image receiving tape on which a label is printed. The image receiving tape has an image receiving layer for receiving the image and an adhesive layer for allowing the label to be adhered to a surface.

The keyboard has a plurality of data entry keys103such as numbered, lettered and punctuation keys for inputting data to be printed as a label and function keys for editing the input data. The keyboard may also have a print key104which is operated when it is desired that a label be printed. Additionally an on/off key105is also provided for switching the tape printing apparatus on and off.

The tape printing apparatus has a liquid crystal display (LCD)106which displays the data as it is entered. The display 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 is driven by a display driver (not shown).

Basic circuitry for controlling the tape printing device100is shown inFIG. 12. There is a microprocessor chip200having a read only memory (ROM)202, a microprocessor201and random access memory capacity indicated diagrammatically by RAM204. The microprocessor chip200is connected to receive label data input to it from a data input device such as the keyboard101. The microprocessor chip200outputs data to drive the display106via a display driver chip209to display a label to be printed (or a part thereof) and/or a message for the user. The display driver alternatively may form part of the microprocessor chip. Additionally, the microprocessor chip200also outputs data to drive a print head206so that the label data is printed onto the image receiving tape to form a label. The microprocessor chip200also controls a motor207for driving the tape. Finally the microprocessor chip100also controls a motor97for operating a cutting mechanism58to allow a length of tape to be cut off. The manner in which the cutting mechanism is controlled will be discussed hereinafter.

In one embodiment of the disclosure the tape printer100may be arranged print to an image on an image receiving tape using an ink ribbon. This method of printing is known as thermal transfer printing.FIG. 13shows a schematic diagram of a cassette receiving bay102in the tape printing apparatus100arranged to print by thermal transfer. In this embodiment an ink ribbon cassette52containing an ink ribbon45is installed together with an image receiving tape cassette50in the cassette receiving bay102. The image receiving tape cassette50contains a supply of image receiving tape40provided on a supply spool88.

The cassette bay102also accommodates at least one thermal print head206and a platen80which cooperate to define a print zone53. The print head206is able to pivot about a pivot point54so that it can be brought into contact with the platen80for printing and moved away from the platen80to enable the cassette50to be removed and replaced. In the operative position, in one embodiment of the disclosure the platen80is rotated by a motor207(FIG. 12) to cause the tape40to be driven past the print head206to the cutting zone59.

The ink ribbon45passes through the print zone together with the image receiving tape40. According to this embodiment of the disclosure the image receiving tape40is an ink receiving tape.

In an alternative embodiment of the disclosure the image receiving tape40is a direct thermal material. In this embodiment of the invention the print head206produces an image on the tape by applying heat directly to the tape40. Accordingly when the image receiving tape cassette50includes direct thermal tape40there is no need to provide an ink ribbon cassette52in the cassette receiving bay102of the printer100.

In one embodiment of the invention the image receiving tape may comprise a continuous image receiving layer. In an alternative embodiment of the present invention the image receiving tape may comprise die cut labels.

Reference is now made toFIG. 1.FIG. 1shows a cutter mechanism according to an embodiment of the present disclosure. The cutter mechanism includes a cutter support1, a rotating blade support2, a translating blade support3on which a blade7is fixed and a clamp8.

FIG. 3shows the cutter support1in more detail. A guide track15is provided on the base4of the cutter support. The guide track15defines a substantially oval path between two walls15aand15b. Although the guide track is shown to be substantially oval inFIG. 3in other embodiments of the invention the guide track may define a predetermined path of any other shape.

A support member9extends perpendicularly from the base4of the cutter support. The cutter support1further comprises end panels12and13, side panels10and11. A hole22is also provided in the base4of the cutter support1. As shown inFIG. 1the clamp8is located between the cutter support1and the rotating blade support2. The clamp8is shown in more detail inFIG. 14.FIG. 14shows the side of the clamp8that is positioned against the base4of the cutter support1. The clamp8comprises a clamping face24and two spring receiving recesses5aand6alocated at the opposite end of the clamp to the clamping face24. The clamp has a cut out section29, which exposes the guide track15when the clamp is attached to the cutter support1. The clamp further comprises an elliptical sleeve44through which the support member9may protrude when the clamp is connected to the cutter support1.

The clamp8is slideably connected to the cutter support1between the two opposing side panels10and11of the cutter support1. The clamp8is resiliently connected to the cutter support by two springs5and6that are located in the spring receiving recesses5aand6aand act upon the end panels12and13of the cutter support1.

The rotating blade support2, shown in more detail inFIG. 9, comprises a cylindrical sleeve34in which support member9of the cutter support is received such that the rotating blade support2is pivotally mounted on the cutter support1. A projecting arm14of the rotating blade support2extends substantially radially from the support member9in the plane in which the rotating blade support2pivots about the support member9.

The translating blade support3is shown from a top elevation inFIG. 10aand from a bottom elevation inFIG. 10b. The translating blade support3is slideably connected to the projecting arm14of the rotating blade support2by flanges37and38that correspond with a recess17which extends along the length of the projecting arm14. The projecting arm14of the rotating blade support2includes a substantially rectangular shaped slot36(FIG. 9) through which a pin28of the translating blade support3engages with the guide track15located on the cutter support1.

FIG. 2shows a view of the cutter mechanism with the rotating blade support2removed. As shown the clamp8includes a cut out section29exposing the guide track15and a cutter arm16. The cutter arm16is shown in more detail inFIG. 8. The cutter arm16comprises an elongated body16awhich is mounted at one end on spindle20. A pin21is mounted at the opposite end of the body16afrom the spindle20. The pin21extends perpendicular to the plane of rotation of the cutter arm16about the spindle20. The spindle20extends through the hole22(FIG. 3) in the cutter support1so that the cutter arm16can be rotated in the direction ‘A’ by the motor97(FIG. 12).

The pin21may act against the inside edge of a region of the cut out section of the clamp8. The pin21of the cutter arm16also projects into a narrow slot32(FIG. 9) in the rotating blade support2which extends towards the projecting arm14of the rotating blade support, such that when the pin21rotates about the spindle20the rotating blade support2is caused to reciprocate along an arc.

Reference is again made toFIG. 3which shows the cutter support1. In operation the pin28attached to the translating blade support3is arranged to follow the path defined by the guide track15. In the embodiment described the predetermined path defined by the guide track is a closed loop path. Therefore the pin attached is arranged to follow the path in one direction, for example a clockwise direction indicated by arrow C.

Alternatively the predetermined path may be a single path having two ends that the pin28must reciprocate between in order to for the translating blade support to move through a complete cutting cycle.

Two stepped edges22and23are provided along at the points in the path. The purpose of the stepped edges22and23is to prevent the pin28from moving in an anti clockwise direction when changing direction at the extremes of the oval path of the guide track15.

As shown inFIG. 2, the cutting mechanism is orientated relative to the image receiving tape40such that the clamping face24of the clamp8extends across the width of the tape at the cutting zone59.

During printing the clamp is held in a retracted position against springs5and6, away from the tape. The clamp is held in the retracted position when the cutter arm16is in the home position as shown inFIG. 2. When the cutter arm is in the home position the pin21of the cutter arm16abuts against the end of an arc30section in the cut out portion of the clamp8as shown.

The operation of the cutting mechanism according to an embodiment of the disclosure will now be described with reference toFIGS. 4,5,6and7.

FIG. 4ashows the position of the blade relative to the tape40when the cutter arm is in the home position. As shown the clamp8and blade7are retracted away from the tape. The position of the rotating blade support is controlled by the position of arm21of the cutter arm16in slot32of the rotating blade.

FIG. 4bshows the corresponding position of the pin21within the slot32of the rotating blade support when the cutter arm16is in the home position.FIG. 4balso shows the path of motion26of the pin21and the path of motion27of the slot32.

The position of the rotating blade support2controls the position of the pin28(FIG. 10), which projects from the translating blade support3, in the guide track15.FIG. 4cshows the corresponding position of the pin28in the guide track15when the cutter arm is in the home position. When the pin is at the position shown inFIG. 4cthe translating blade support which holds the blade will be completely retracted within the arm14of the rotating blade support2.

When a cutting operation is initiated by the processor200, the motor97is controlled by the processor200to drive the spindle20of the cutter arm in the direction ‘A’ shown inFIG. 8such that the pin21of the cutter arm disengages with the arc30of the cut out section29in the clamp8. The clamp is biased towards the tape by springs5and6. When the cutter arm disengages with the arc30, the clamp is forced towards the tape40. The clamp face24clamps the tape onto the housing of the cassette. In an alternative embodiment of the invention the clamp may be arranged to clamp the tape onto the housing of the printer or any other surface fixed relative to the body of the printer.

FIG. 5ashows the position of the blade relative to the tape40when the cutter arm16is rotated clockwise from the home position. In this position the clamp8is positioned against the tape40and the blade7and translating blade support are above the tape40.

FIG. 5bshows the corresponding position of the pin21within the slot32of the rotating blade support2when the cutter arm is rotated clockwise from the home position. As shown, when the rotating blade support is at the upper position the slot is at one end of the path of motion27.

FIG. 5cshows the corresponding position of the pin28in the guide track15when the rotating blade support is in the upper position. When the pin28is at the position shown inFIG. 5cthe translating blade support3which holds the blade will be partially extended from the arm14of the rotating blade support2to which it is slideaby connected.

FIG. 6ashows the position of the blade relative to the tape40when the cutter arm is rotated clockwise from the position shown inFIG. 5a. In this position the clamp8remains against the tape40and the blade7is midway through cutting the tape40.

FIG. 6bshows the corresponding position of the pin21within the slot32of the rotating blade support when the cutter arm is rotated clockwise from the position shown inFIG. 5b. As shown the rotating blade support is between the two extremes of the path27followed by the slot32.

FIG. 6cshows the corresponding position of the pin28in the guide track15when the rotating blade support is midway through the cutting position. When the pin is at the position shown inFIG. 6cthe translating blade support3which holds the blade7will be partially extended from the arm14of the rotating blade support2to which it is slideaby connected. In one embodiment of the disclosure the distance from the pivot9to the position of the pin28on the path inFIG. 5cis greater than the distance from the pivot9to the position of the pin28on the path inFIG. 6c. This causes the translating blade support to be retracted slightly when the rotating blade support2moves from the upper position as shown inFIG. 5to the mid cutting position as shown inFIG. 6. This advantageously causes different points along the blade to intersect the tape as the blade transverses and cuts the tape. This prevents excessive wear on one point on the blade7. This also prevents a build up of adhesive on the blade when cutting the adhesive layer of the tape.

FIG. 7ashows the position of the blade relative to the tape40when the cutter arm is rotated clockwise from the position of the cutter arm inFIG. 6a. In this position the clamp8remains against the tape40and the blade7has completed cutting the tape40.

FIG. 7bshows the corresponding position of the pin21within the slot32of the rotating blade support2when the cutter arm is rotated clockwise from the position of the cutter arm shown inFIG. 6b. As shown the rotating blade support is at the furthest point in the path27.

FIG. 7cshows the corresponding position of the pin28in the guide track15when the rotating blade support is at the lowest point in its path of motion. When the pin is at the position shown inFIG. 7cthe translating blade support3which holds the blade7will be retracted further along the arm14of the rotating blade support2to which it is slideaby connected.

The motor continues to rotate the spindle20until the cutter arm16returns to the home position as shown inFIGS. 2 and 4b. As the cutter arm rotates towards the home position the arm21of the cutter arm16abuts against the arc30of the cut out section29of clamp8. The cutter arm retracts the clamp away from the tape and moves the rotating blade support to the position as shown inFIG. 4a.

When the rotating blade support moves upwards towards the home position the pin28connected to the translating blade support2continues to follow the guide track back to the position as shown inFIG. 4c. Since the distance between this portion of the path followed by the pin during the upward movement of the blade and the pivot9is less than the distance between the portion of the path followed by the pin during the downward movement of the blade and the pivot9, the blade is retracted when the rotating blade support returns to the home position. Accordingly when the rotating blade support returns to the home position the blade is retracted along the arm14and held away from the tape40.

According to an embodiment of the disclosure, the home position of the cutter arm16may be detected by a switch60.FIG. 15shows a plunger switch60that may be used to detect the home position of the cutter arm16. The plunger switch60includes a sloped plunger57. The switch60may be attached to the cutter support1at a location, as shown inFIG. 7c, that causes the plunger57to be depressed when the cutter arm returns to the home position. When the plunger57is depressed a signal is sent from the switch60to the microprocessor chip200to indicate that the cutter arm has returned to the home position and that the cutting cycle is complete. In response to the signal received from the switch60the microprocessor controls the motor97to stop the rotation of the cutter arm16.

In a preferred embodiment of the disclosure the blade is arranged to move along the width of the tape40.

When the cutting mechanism is orientated relative to the tape as shown inFIG. 2, any force exerted by cutting the tape when blade moves though the cutting cycle shown inFIGS. 4 to 7is directed toward the base of the cassette receiving bay102. As such the force caused by cutting the tape will not displace the position of the tape.

A further embodiment of the disclosure will now be described with reference toFIGS. 16 and 17.

During a cutting cycle, when the blade7is in contact with the tape, the translating blade support3is extended from the projecting arm14of the rotating blade support2. In this extended position the lateral support provided for the blade, which is perpendicular to the plane of the blade, is limited.

When the blade7is in contact with the tape, the interaction of the blade7and the tape causes a force to act on the tape. This causes the tape40to distort as shown inFIG. 18. This is particularly pronounced when a projection of the tape cassette50supports the bottom edge of the tape.

Similarly when the blade interacts with the tape a force also acts on the blade. Without lateral support to guide the path of the blade during the cutting cycle, the path of motion of the blade will be offset by the resistance provided by the tape, thus causing an irregular cut surface that is not straight and smooth.

In the embodiments of the invention described thus far, the blade may be supported on one side by the edge of the clamping face24of the clamp8as shown inFIG. 1. The support provided by the clamping face24in the embodiment shown inFIG. 1will however not prevent the blade from moving away from the edge of the clamping face during the cutting cycle.

Also, the lateral movement of the blade7may also be restricted by a slot150located in the housing of the tape cassette as shown inFIG. 2. However, since the purpose of the slot150in the housing of the tape cassette is to accommodate the blade7during a cutting cycle, the dimensions of the slot150in the cassette are not suited to providing lateral support to the blade during the cutting cycle, especially when the tape cassette is designed for use in more than one type of printer.

According to an embodiment of the invention that is provided to solve this problem, the clamp8is arranged to prevent the tape from distorting and to provide lateral support on both sides of the blade when the blade is in contact with the tape.

As shown inFIG. 16a slot151is provided in the clamping face24of the claim8.

Referring now toFIG. 17, the slot151in the clamping face24of the clamp8is arranged to receive the blade7, such that during the cutting cycle the blade7will extend through the slot to contact the tape.

In one embodiment of the disclosure the blade may only extend through the slot151when the translating blade support member3is extended and the blade is in the cutting position.

In a preferred embodiment of the disclosure the blade may also be arranged to extend into the slot when the blade is retracted and the rotating blade support is in the home position. This arrangement will prevent the blade from jamming behind the clamping face. In order to prevent the blade from jamming it is not necessary for the blade to extend through the slot. Instead it is sufficient for the blade to project into the slot such that the blade7is supported by an internal wall of the slot151.

As the clamping face24of the clamp8is arranged to clamp the tape on either side of the blade7while the tape is being cut by the blade, this prevents the tape from distorting during the cutting operation.

A further advantage of clamping the tape on either side of the blade is that the clamp provides lateral support on both sides of the blade. This ensures that the cut surface of the tape is straight.

A further advantage to clamping the tape on either side of the blade is that the tape is held in place on either side of the blade while the tape is being cut.

Whilst the embodiments of the present disclosure have been described in relation to tape printers, embodiments of the present disclosure may also be applied to other printers, such as laser printers, PC printers and stand alone printers, having a cutting mechanism that is used to cut off the image receiving medium.

Printers embodying the present disclosure may be capable of monochrome printing, grayscale printing or full colour printing.

The present disclosure may include any feature or combination of features disclosed herein either implicitly or explicitly or any generalization thereof, without limitation to the scope of any of the present claims. In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention.