Image generating apparatus with ink sheet cartridge ejection suppression

An image generating apparatus applicable to a structure employing an ink sheet cartridge having an outwardly exposed ink sheet, capable of suppressing ejection of the ink sheet cartridge in printing and capable of suppressing reduction of printing quality is obtained. This image generating apparatus comprises an ink sheet cartridge, a chassis, a first stop member provided outside the chassis for engaging with the ink sheet cartridge and a second stop member provided inside the chassis for engaging with the ink sheet cartridge in printing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image generating apparatus, and more particularly, it relates to an image generating apparatus comprising an ink sheet cartridge.

2. Description of the Background Art

A thermal transfer printer comprising an ink sheet cartridge is known in general, as disclosed in Japanese Patent Laying-Open No. 2003-89257, for example.

The aforementioned Japanese Patent Laying-Open No. 2003-89257 describes the structure of a thermal transfer printer comprising an ink sheet cartridge, which can be easily ejected from a cartridge mount portion by sliding an ejection member (stop member). In this thermal transfer printer, a rib portion of the ink sheet cartridge is fitted with a stop portion provided on a print head mount. The ejection member is so slid that an inclined portion thereof urges a projection of the ink sheet cartridge in an ejective direction. Thus, the rib portion of the ink sheet cartridge escapes from the stop portion of the print head mount, so that the ink sheet cartridge is ejected. The ejection member can be slid not only in nonprinting, but also in printing.

A thermal transfer printer is generally known as an exemplary image generating apparatus.FIG. 19is an overall perspective view of an exemplary conventional thermal transfer printer.FIG. 20is a sectional view of the exemplary conventional thermal transfer printer shown inFIG. 19. The structure of the exemplary conventional thermal transfer printer is described with reference toFIGS. 19 and 20.

As shown inFIGS. 19 and 20, the conventional thermal transfer printer comprises a chassis101of metal, a print head102(seeFIG. 20) for printing, a platen roller103(seeFIG. 20) arranged oppositely to the print head102, a feed roller105carrying a paper104, a press roller106pressing the feed roller105and a stop member107. An ink sheet cartridge108storing an ink sheet108afor transferring ink to the paper104is mounted on the conventional thermal transfer printer. The chassis101has first and second side surfaces101aand101b, as shown inFIG. 19. A cartridge receiving hole101cis provided on the second side surface101bof the chassis101for receiving the ink sheet cartridge108.

As shown inFIG. 19, the stop member107is provided outside the second side surface101bof the chassis101. This stop member107is provided with a support shaft107arotatably supporting the stop member107, an engaging pawl107bengaging with an engaging portion108gof the ink sheet cartridge108, a grip107cheld by a user for lifting the stop member107upward (along arrow B) and a spring portion107dsupplying urging force for rotating the engaging pawl107bof the stop member107downward when the user lifts up the stop member107through the grip. The stop member107has a function of inhibiting the ink sheet cartridge108from moving in an ejective direction (along arrow A inFIG. 19).

As shown inFIG. 20, the ink sheet cartridge108includes a feed bobbin108bfor feeding the ink sheet108aand a take-up bobbin108cfor taking up the fed ink sheet108a. A cartridge case forming the ink sheet cartridge108is constituted of a feed bobbin storage portion108drotatably storing the feed bobbin108b, a take-up bobbin storage portion108erotatably storing the take-up bobbin108cand a pair of coupling portions108fcoupling the feed bobbin storage portion108dand the take-up bobbin storage portion108ewith each other at a prescribed distance. When the feed bobbin storage portion108dand the take-up bobbin storage portion108estore the feed bobbin180band the take-up bobbin108crespectively, therefore, the ink sheet108awound on the feed bobbin180band the take-up bobbin108cis outwardly exposed on the space of the prescribed distance between the feed bobbin storage portion108dand the take-up bobbin storage portion108e. The engaging portion108g(seeFIG. 19) engaging with the engaging pawl107bof the stop member107provided on the second side surface101bof the chassis101is provided on one of the pair of coupling portions108f. The ink sheet cartridge108is provided with a helical compression spring (not shown), which regularly urges the ink sheet cartridge108mounted on the thermal transfer printer along arrow A inFIG. 19.

As shown inFIG. 20, the print head102has a support shaft102aforming the rotation center of the print head102, a head portion102b, an arm portion102cand a heat sink portion102dfor radiating heat from the head portion102b. As shown inFIG. 20, further, the print head102is mounted on the first and second side surfaces101aand101bof the chassis101to be rotatable about the support shaft102a.

A printing operation of the conventional thermal transfer printer is described with reference toFIG. 20. When the print head102rotates along arrow C, the head portion102bthereof comes into contact with the ink sheet108aoutwardly exposed from the ink sheet cartridge108, as shown inFIG. 20. When the print head102further rotates, the ink sheet108acomes into contact with the fed paper104. The head portion102bof the print head102and the platen roller103press the ink sheet108aand the paper104. In this state, the take-up bobbin108ctakes up the ink sheet108a, while the feed roller105carries the paper104in a paper discharge direction (along arrow D inFIG. 20). At this time, the head portion102bof the print head102generates heat, to melt the ink of the ink sheet108a. Thus, the ink is transferred from the ink sheet108ato the paper104, for printing an image on the paper104.

An operation of ejecting the ink sheet cartridge108from the conventional thermal transfer printer is described with reference toFIG. 19. When the ink sheet cartridge108is mounted on the thermal transfer printer, the engaging portion108gof the ink sheet cartridge108and the engaging pawl107bof the stop member107engage with each other, as shown inFIG. 19. The helical compression spring (not shown) regularly urges the ink sheet cartridge108along arrow A. When the user lifts the stop member107upward (along arrow B) through the grip107c, the engaging portion108gof the ink sheet cartridge108and the engaging pawl107bof the stop member107disengage from each other. Thus, the ink sheet cartridge108jumps out of the thermal transfer printer along arrow A inFIG. 19, due to the urging force of the helical compression spring (not shown). Thereafter the user ejects the ink sheet cartridge108by manually extracting the same from the ink sheet cartridge receiving hole101cof the chassis101.

In the conventional thermal transfer printer shown inFIGS. 19 and 20, however, the user can eject the ink sheet cartridge108as described above also in printing since the stop member107for ejecting the ink sheet cartridge108is provided outside the second side surface101bof the chassis101. If the user accidentally ejects the ink sheet cartridge108during the aforementioned printing operation, therefore, the ink sheet108apressed by the head portion102bof the print head102and the platen roller103may be broken, or the ink sheet108amay be entangled in the thermal transfer printer to cause a failure in the thermal transfer printer.

In the thermal transfer printer described in the aforementioned Japanese Patent Laying-Open No. 2003-89257, the ejection member for ejecting the ink sheet cartridge is sidable not only in nonprinting but also in printing. If the user accidentally slides the ejection member in printing, therefore, the ink sheet may be broken, or may be entangled in the thermal transfer printer to cause a failure in the thermal transfer printer.

In this regard, various thermal transfer printers capable of suppressing ejection of ink sheet cartridges in printing are proposed in general, as disclosed in Japanese Patent Laying-Open Nos. 2001-38976, 11-268315 (1999) and 2-81661 (1990), for example.

The aforementioned Japanese Patent Laying-Open No. 2001-38976 proposes a thermal transfer printer, comprising an ink sheet cartridge, capable of suppressing ejection of the ink sheet cartridge in printing. In this thermal transfer printer, a projecting portion is provided on a free end of a cantilevered print head mount. The print head mount is provided with a print head, which is pressed by a platen roller in printing so that the print head mount is deflected to move the free end. Thus, the projecting portion of the print head mount engages with an end surface of the ink sheet cartridge, for suppressing ejection of the ink sheet cartridge. The ink sheet cartridge is provided with a grab, so that the user ejects the ink sheet cartridge by pulling this grab.

The aforementioned Japanese Patent Laying-Open No. 11-268315 proposes a thermal transfer printer, comprising an ink sheet cartridge, having a cartridge ejection preventing portion provided on a rotating arm rotating a print head. In this thermal transfer printer, the cartridge ejection preventing portion engages with a cartridge engaging member suppressing ejection of the ink sheet cartridge following rotation of the print head. Thus, thermal transfer printer can so inhibit the cartridge engaging member from rotation that it is difficult for the user to rotate the same, whereby the thermal transfer printer can suppress ejection of the ink sheet cartridge in printing. When the user operates the cartridge engaging member engaging with the cartridge ejection preventing portion in the thermal transfer printer proposed in Japanese Patent Laying-Open No. 11-268315, urging force is applied to the rotating arm.

The aforementioned Japanese Patent Laying-Open No. 2-81661 proposes a thermal transfer printer, provided with an ink sheet cartridge having an unexposed ink sheet, capable of suppressing ejection of the ink sheet cartridge through engagement of an engaging portion rotating following rotation of a loading arm for ejecting a take-up bobbin from a cartridge case for outwardly exposing the ink sheet with a notch provided on the ink sheet cartridge. In this thermal transfer printer, the loading arm ejects the take-up bobbin from the ink sheet cartridge in printing, thereby suppressing ejection of the ink sheet cartridge during the printing.

In the thermal transfer printer proposed in the aforementioned Japanese Patent Laying-Open No. 2001-38976, however, urging force is disadvantageously applied to the print head mount engaging with the end surface of the ink sheet cartridge when the user pulls the grab of the ink sheet cartridge in printing. Therefore, the position of the print head provided on the print head mount deviates in printing, to disadvantageously reduce printing quality.

In the thermal transfer printer proposed in the aforementioned Japanese Patent Laying-Open No. 11-268315, urging force is disadvantageously applied to the rotating arm through the cartridge ejection preventing portion when the user operates the cartridge engaging member in printing. Therefore, the position of the print head deviates in printing to reduce printing quality, similarly to the aforementioned Japanese Patent Laying-Open No. 2001-38976.

The thermal transfer printer proposed in the aforementioned Japanese Patent Laying-Open No. 2-81661, provided with the engaging portion engaging with the notch of the ink sheet cartridge and rotating following rotation of the loading arm ejecting the take-up bobbin from the cartridge, presupposes the structure having the loading arm for ejecting the take-up bobbin from the cartridge case. Therefore, it is disadvantageously difficult to apply the structure of the thermal transfer printer proposed in the aforementioned Japanese Patent Laying-Open No. 2-81661 to a thermal transfer printer employing an ink sheet cartridge having a regularly outwardly exposed ink sheet, from which no take-up bobbin may be ejected.

SUMMARY OF THE INVENTION

The present invention has been proposed in order to solve the aforementioned problems, and an object of the present invention is to provide an image generating apparatus applicable to a structure employing an ink sheet cartridge having an outwardly exposed ink sheet, capable of suppressing ejection of the ink sheet cartridge in printing and capable of suppressing reduction of printing quality.

In order to attain the aforementioned object, an image generating apparatus according to a first aspect of the present invention comprises an ink sheet cartridge including a cartridge case provided with a feed bobbin storage portion and a take-up bobbin storage portion coupled with each other through a pair of coupling portions at a prescribed interval, a feed bobbin and a take-up bobbin stored in the cartridge case and an ink sheet outwardly exposed between the feed bobbin storage portion and the take-up bobbin storage portion, a chassis mounted with the ink sheet cartridge, a first stop member provided outside the chassis for engaging with the ink sheet cartridge and a second stop member provided inside the chassis for engaging with the ink sheet cartridge in printing.

The image generating apparatus according to the first aspect, comprising the cartridge case provided with the feed bobbin storage portion and the take-up bobbin storage portion coupled with each other through the pair of coupling portions at the prescribed interval, the feed bobbin and the take-up bobbin stored in the cartridge case and the ink sheet outwardly exposed between the feed bobbin storage portion and the take-up bobbin storage portion as hereinabove described, has the first stop member provided outside the chassis and the second stop member provided inside the chassis for engaging with the ink sheet cartridge in printing so that the same can suppress ejection of the ink sheet cartridge in printing due to engagement between the second stop member and the ink sheet cartridge in the chassis, also when a user disengages the first stop member provided outside the chassis and the ink sheet cartridge from each other in printing. Consequently, the image generating apparatus can suppress breakage of the ink sheet, and can prevent a failure resulting from entanglement of the ink sheet therein. Further, the image generating apparatus comprising the ink sheet cartridge including the outwardly exposed ink sheet is so formed with the second stop member provided inside the chassis that the user can be inhibited from touching the second stop member, whereby the second stop member can be prevented from application of a load in printing. Thus, the image generating apparatus can prevent members provided inside the chassis from application of a load in printing, thereby suppressing reduction of printing quality.

The aforementioned image generating apparatus according to the first aspect preferably further comprises a print head for printing, a platen roller arranged on a position opposite to the print head and a press member pressing the print head against the platen roller, and the second stop member is preferably mounted on a rotating shaft of the press member. According to this structure, the image generating apparatus can rotate the second stop member following rotation of the press member rotating the print head in printing, whereby the second stop member can engage with the ink sheet cartridge in printing without a dedicated drive source. Consequently, the image generating apparatus can easily suppress ejection of the ink sheet cartridge in printing.

In the aforementioned image generating apparatus comprising the print head, the platen roller and the press member, the second stop member is preferably unidly mounted with respect to the rotating shaft. According to this structure, the second stop member can unidly rotate with respect to the rotating shaft of the press member rotating the print head in printing following rotation of the rotating shaft, whereby the second stop member can easily engage with the ink sheet cartridge in printing.

In this case, an oval stop member insert portion is preferably provided on a portion of the rotating shaft mounted with the second stop member, and an oval rotating shaft receiving hole is preferably provided on a portion of the second stop member receiving the rotating shaft. According to this structure, the second stop member can be easily unidly mounted with respect to the rotating shaft by inserting the oval stop member insert portion of the rotating shaft into the oval rotating shaft receiving hole of the second stop member.

In the aforementioned image generating apparatus according to the first aspect, the ink sheet cartridge is preferably provided with an engaging portion engaging with the second stop member. According to this structure, the second stop member can easily engage with the engaging portion of the ink sheet cartridge, thereby easily suppressing ejection of the ink sheet cartridge.

In the aforementioned image generating apparatus having the ink sheet cartridge provided with the engaging portion engaging with the second stop member, the engaging portion of the ink sheet cartridge preferably includes a groove portion engaging with both surfaces of the second stop member. According to this structure, the image generating apparatus can inhibit the ink sheet cartridge from movement not only in an ejective direction but also in a direction opposite thereto. Thus, the image generating apparatus can suppress reduction of printing quality resulting from misregistration in the direction opposite to the ejective direction for the ink sheet.

In the aforementioned image generating apparatus having the ink sheet cartridge provided with the engaging portion including the groove portion engaging with both surfaces of the second stop member, the ink sheet cartridge preferably further includes a multicolor ink sheet, and the second stop member preferably rotates following rotation of the print head and engages with the groove portion while the print head vertically rotates for printing the multicolor ink sheet. According to this structure, the image generating apparatus can suppress ejection of the ink sheet cartridge also when the user disengages the first stop member and the ink sheet cartridge from each other while the print head separates from the platen roller upon completion of printing in each color. Thus, the image generating apparatus can suppress imperfect completion of printing resulting from ejection of the ink sheet cartridge in an intermediate stage of printing in each color.

In this case, the groove portion preferably has a slender shape. According to this structure, the image generating apparatus can so increase the area of the groove portion engaging with the second stop member as to inhibit the second stop member from disengaging from the slender groove portion when the print head rotates to separate from the platen roller upon completion of printing in each color. Thus, the second stop member can easily engage with the groove portion also when the print head separates from the platen roller upon completion of printing in each color.

In the aforementioned image generating apparatus having the ink sheet cartridge provided with the engaging portion including the groove portion engaging with both surfaces of the second stop member, the groove portion is preferably provided on either coupling portion of the ink sheet cartridge. According to this structure, the groove portion is so located around a central portion between the take-up bobbin storage portion and the feed bobbin storage portion that the second stop member can engage with the groove portion around the central portion between the take-up bobbin storage portion and the feed bobbin storage portion. Therefore, the second stop member can inhibit the ink sheet cartridge from movement around the central portion between the take-up bobbin storage portion and the feed bobbin storage portion of the ink sheet cartridge, whereby the image generating apparatus can more stably inhibit the ink sheet cartridge from movement as compared with a case of inhibiting the ink sheet cartridge from movement on the side of the feed bobbin storage portion or the take-up bobbin storage portion.

In the aforementioned image generating apparatus having the ink sheet cartridge provided with the engaging portion engaging with the second stop member, a portion of the second stop member engaging with the engaging portion of the ink sheet cartridge is preferably arcuately formed. According to this structure, the second stop member can so easily partially engage with the engaging portion that the image generating apparatus can easily keep the second stop member and the engaging portion in engagement also when the print head vertically rotates in printing.

An image generating apparatus according to a second aspect comprises an ink sheet cartridge including a cartridge case provided with a feed bobbin storage portion and a take-up bobbin storage portion coupled with each other through a pair of coupling portions at a prescribed interval, a feed bobbin and a take-up bobbin stored in the cartridge case and a multicolor ink sheet outwardly exposed between the feed bobbin storage portion and the take-up bobbin storage portion, a chassis mounted with the ink sheet cartridge, a print head for printing, a platen roller arranged on a position opposite to the print head, a press member pressing the print head against the platen roller, a first stop member provided outside the chassis for engaging with the ink sheet cartridge and a second stop member provided inside the chassis for engaging with the ink sheet cartridge in printing, the ink sheet cartridge is provided with a groove portion engaging with both surfaces of the second stop member, the groove portion is provided on either coupling portion of the ink sheet cartridge, the second stop member is mounted on a rotating shaft of the press member for rotating following rotation of the print head and engaging with the groove portion while the print head vertically rotates for printing the multicolor ink sheet, and a portion of the second stop member engaging with the ink sheet cartridge is arcuately formed.

The image generating apparatus according to the second aspect, comprising the cartridge case provided with the feed bobbin storage portion and the take-up bobbin storage portion coupled with each other through the pair of coupling portions at the prescribed interval, the feed bobbin and the take-up bobbin stored in the cartridge case and the ink sheet outwardly exposed between the feed bobbin storage portion and the take-up bobbin storage portion as hereinabove described, has the first stop member provided outside the chassis and the second stop member provided inside the chassis for engaging with the ink sheet cartridge in printing so that the same can suppress ejection of the ink sheet cartridge in printing due to engagement between the second stop member and the ink sheet cartridge in the chassis, also when a user disengages the first stop member provided outside the chassis and the ink sheet cartridge from each other in printing. Consequently, the image generating apparatus can suppress breakage of the ink sheet, and can prevent a failure resulting from entanglement of the ink sheet therein. Further, the image generating apparatus comprising the ink sheet cartridge including the outwardly exposed ink sheet is so formed with the second stop member provided inside the chassis that the user can be inhibited from touching the second stop member, whereby the second stop member can be prevented from application of a load in printing. Thus, the image generating apparatus can prevent members provided inside the chassis from application of a load in printing, thereby suppressing reduction of printing quality. In addition, the image generating apparatus can rotate the second stop member following rotation of the press member rotating the print head in printing, whereby the second stop member can engage with the ink sheet cartridge in printing without a dedicated drive source. Consequently, the image generating apparatus can easily suppress ejection of the ink sheet cartridge in printing.

According to the second aspect, further, the image generating apparatus, having the ink sheet cartridge provided with the groove portion engaging with both surfaces of the second stop member, can inhibit the ink sheet cartridge from movement not only in an ejective direction but also in a direction opposite thereto. Thus, the image generating apparatus can suppress reduction of printing quality resulting from misregistration in the direction opposite to the ejective direction for the ink sheet. In addition, the second stop member rotates following rotation of the print head and engages with the groove portion while the print head vertically rotates for printing the multicolor ink sheet, whereby the image generating apparatus can suppress ejection of the ink sheet cartridge also when the user disengages the first stop member and the ink sheet cartridge from each other while the print head separates from the platen roller upon completion of printing in each color. Thus, the image generating apparatus can suppress imperfect completion of printing resulting from ejection of the ink sheet cartridge in an intermediate stage of printing in each color. Further, the groove portion, provided on either coupling portion of the ink sheet cartridge, is so located around a central portion between the take-up bobbin storage portion and the feed bobbin storage portion that the second stop member can engage with the groove portion around the central portion between the take-up bobbin storage portion and the feed bobbin storage portion. Therefore, the second stop member can inhibit the ink sheet cartridge from movement around the central portion between the take-up bobbin storage portion and the feed bobbin storage portion of the ink sheet cartridge, whereby the image generating apparatus can more stably inhibit the ink sheet cartridge from movement as compared with a case of inhibiting the ink sheet cartridge from movement on the side of the feed bobbin storage portion or the take-up bobbin storage portion. Further, the portion of the second stop member engaging with the ink sheet cartridge is arcuately formed, whereby the second stop member can so easily partially engage with the groove portion that the image generating apparatus can easily keep the second stop member and the groove portion in engagement also when the print head vertically rotates in printing.

In the aforementioned image generating apparatus according to the second aspect, the second stop member is preferably unidly mounted with respect to the rotating shaft. According to this structure, the second stop member can unidly rotate with respect to the rotating shaft of the press member rotating the print head in printing following rotation of the rotating shaft, so that the second stop member can easily engage with the ink sheet cartridge in printing.

In this case, an oval stop member insert portion is preferably provided on a portion of the rotating shaft mounted with the second stop member, and an oval rotating shaft receiving hole is preferably provided on a portion of the second stop member receiving the rotating shaft. According to this structure, the second stop member can be easily unidly mounted with respect to the rotating shaft by inserting the oval stop member insert portion of the rotating shaft into the oval rotating shaft receiving hole of the second stop member.

In the aforementioned image generating apparatus according to the second aspect, the groove portion preferably has a slender shape. According to this structure, the image generating apparatus can so increase the area of the groove portion engaging with the second stop member as to inhibit the second stop member from disengaging from the slender groove portion when the print head rotates to separate from the platen roller upon completion of printing in each color. Thus, the second stop member can easily engage with the groove portion also when the print head separates from the platen roller upon completion of printing in each color.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention is now described with reference to the drawings.

The structure of a thermal transfer printer according to this embodiment is described with reference toFIGS. 1 to 13. According to this embodiment, the present invention is applied to the thermal transfer printer, which is an exemplary image generating apparatus.

As shown inFIGS. 1 to 4and13, the thermal transfer printer according to this embodiment comprises a chassis1of metal, a print head2for printing, a platen roller3arranged oppositely to the print head2, two platen roller bearings4rotatably supporting the platen roller3, a support rod5of metal, head portion press members6and7for pressing the print head2, a feed roller9of metal for carrying a paper8(seeFIG. 13), a feed roller gear10(seeFIG. 4), a press roller11of metal pressing the feed roller9with prescribed pressing force, feed roller bearings12and13rotatably supporting the feed roller9, press roller bearings14rotatably supporting the press roller11, bearing support plates15, helical tension springs16for urging the press roller11with pressing force, a motor bracket17, a paper feed motor18(seeFIG. 4) for driving the feed roller9etc., a motor gear18a(seeFIG. 4), a press member rotating motor19(seeFIG. 4) for driving the head portion press members6and7, a drive gear20a, an intermediate gear20b, a swing gear21(seeFIG. 4), intermediate gears22and23(seeFIG. 4) and a take-up reel24. An ink sheet cartridge25(seeFIG. 3) of resin storing ink sheets25ais mounted on the thermal transfer printer according to this embodiment. The support rod5is an example of the “rotating shaft” in the present invention, and the head portion press members6and7are examples of the “press member” in the present invention.

As shown inFIG. 1, the chassis1has first and second side surfaces1aand1band a bottom surface1c. The aforementioned motor bracket17is mounted on the first side surface1aof the chassis1a. A cartridge receiving hole1dfor receiving the ink sheet cartridge25is provided on the second side surface1bof the chassis1opposed to the first side surface1a. The feed roller bearing12supporting a first end of the feed roller9is also provided on the second side surface1bof the chassis1. Further, a side plate26integrally provided with a stop portion26afor inhibiting the ink sheet cartridge25from moving in an ejective direction (along arrow A1inFIG. 1) is mounted outside the second side surface1bof the chassis1. The stop portion26ais provided with a support shaft26brotatably supporting the stop portion26a, an engaging pawl26cengaging with an engaging portion25hof the ink sheet cartridge25, a grip26dheld by a user for lifting the stop portion26aupward (along arrow B1) and a spring portion26esupplying urging force for rotating the engaging pawl26cof the stop portion26adownward (along arrow C1) when the user lifts up the stop portion26athrough the grip26d. The stop portion26ais so formed that the user can eject the ink sheet cartridge25by lifting up the stop portion26athrough the grip26d. The stop portion26ais an example of the “first stop member” in the present invention. Support holes1eare provided on the first and second side surfaces1aand1bof the chassis1respectively, for rotatably supporting the support rod5mounted with the head portion press members6and7. A bent section if is provided on the bottom surface1cof the chassis1by partially uprighting the bottom surface1c. The feed roller bearing13supporting a second end of the feed roller9is provided on this bent section1f, as shown inFIG. 1. A spring mount portion1gmounted with a first end of the helical tension spring16is provided on the bottom surface1cof the chassis1, as shown inFIG. 1.

As shown inFIGS. 7 and 8, first and second support portions5aare provided on first and second ends of the support portion5respectively. The first and second support portions5aof the support rod5are fitted into the support holes1eprovided on the first and second side surfaces1aand1bof the chassis1respectively. As shown inFIGS. 7 and 8, further, the head portion press members6and7are mounted on the first and second ends of the support rod5respectively, unidly with respect to the support rod5. More specifically, D-shaped insert portions5bare provided in the vicinity of both ends of the support rod5respectively, as shown inFIGS. 7 and 8. An oval stop member insert portion5cpress-fitted into a stop member27is provided on the second end of the support rod5.

As shown inFIG. 7, the head portion press member6is integrally formed with a press portion6aand a gear portion6b. As shown inFIG. 8, the head portion press member7is integrally formed with a press portion7aand a projection7bprotruding in the extensional direction of the support rod5.

The head portion press members6and7are formed with D-shaped receiving holes6cand7creceiving the insert portions5bprovided in the vicinity of both ends of the support rod5respectively. Upon rotation of the head portion press member6, therefore, the support rod5rotates, followed by rotation of the head portion press member7. The head portion press members6and7are arranged on the sides of the first and second side surfaces1aand1bof the chassis1respectively, as shown inFIGS. 1 and 2.

According to this embodiment, the stop member27of resin is mounted on the second end of the support rod5. A portion of the stop member27engaging with the ink sheet cartridge25is arcuately formed, as shown inFIG. 6. The arcuately formed portion of the stop member27has an angle of about 40°. Further, the stop member27is provided with an oval support rod receiving hole27a, into which the support rod5is press-fitted. The stop member27is unidly mounted on the support rod5. Upon rotation of the head portion press members6and7, therefore, the stop member27rotates in association with the head portion press members6and7. The stop member27is provided inside the second side surface1bof the chassis1, so that the user cannot touch the same. The stop member27is an example of the “second stop member” in the present invention, and the support rod receiving hole27ais an example of the “rotating shaft receiving hole” in the present invention.

As shown inFIGS. 1 and 13, the print head2has a pair of support shafts2a, a head portion2b(seeFIG. 13), a pair of arm portions2ccoupling the support shafts2aand the head portion2bwith each other and a heat sink portion2dof aluminum for radiating heat from the head portion2b. The pair of support shafts2aof the print head2are vertically rotatably mounted on the inner surfaces of the first and second side surfaces1aand1bof the chassis1respectively. The platen roller3is rotatably supported by the two platen roller bearings4(seeFIG. 1) mounted on the first and second side surfaces1aand1bof the chassis1respectively.

As shown inFIGS. 1 and 2, a spring holder28is fixed to the upper surface of the heat sink portion2dof the print head2with a screw29. This spring holder28is provided with two spring fixing portions28aand28bmounted with two torsion coil springs30and31respectively. The torsion coil spring30has a first end30apressed against the press portion6aof the head portion press member6upon downward rotation of the head portion press member6and a second end30btransmitting urging force resulting from the pressed first end30ato the head portion2b. The torsion coil spring31also has a first end31apressed against the press portion7aof the head portion press member7upon downward rotation of the head portion press member7and a second end31btransmitting urging force resulting from the pressed first end31ato the head portion2b. The head portion2bis pressed against the platen roller3due to the urging force of the torsion coil springs30and31transmitted thereto.

As shown inFIGS. 1 and 13, the spring fixing portion28bof the spring holder28is integrally formed with an engaging portion28dhaving a notch28cengaging with the projection7bof the head portion press member7. When the head portion press member7upwardly rotates, therefore, the projection7bof the head portion press member7and the notch28cof the spring fixing portion28bengage with each other, thereby upwardly rotating the head portion2b. Consequently, the head portion2bhaving been pressed against the platen roller3(seeFIG. 1) separates from the platen roller3upon rotation of the head portion press member7.

The feed roller bearings12and13rotatably support the feed roller9of metal, as shown inFIG. 2. The feed roller9is provided on a first end thereof with a feed roller gear insert portion9a(seeFIG. 4) inserted into the feed roller gear10. The press roller bearings14rotatably support the press roller11of metal, as shown inFIG. 2. The press roller bearings14are mounted on the bearing support plates15provided inside the bent section if provided on the bottom surface1cof the chassis1and the second side surface1bthereof respectively. As shown inFIG. 1, the bearing support plates15are provided inside the bent section1fprovided on the bottom surface1cof the chassis1and the second side surface1bthereof respectively, to be rotatable about support portions15a. Second ends of the helical tension springs16for urging the press roller11toward the feed roller9are mounted on spring mount portions15bof the bearing support plates15.

As shown inFIG. 12, the ink sheet cartridge25includes a feed bobbin25bfor feeding the ink sheets25aand a take-up bobbin25cfor taking up the fed ink sheets25a. A cartridge case forming the ink sheet cartridge25is constituted of a feed bobbin storage portion25drotatably storing the feed bobbin25b, a take-up bobbin storage portion25erotatably storing the take-up bobbin25cand a pair of coupling portions25fand25gcoupling the feed bobbin storage portion25dand the take-up bobbin storage portion25ewith each other at a prescribed distance, as shown inFIGS. 9 to 11. When the feed bobbin storage portion25dand the take-up bobbin storage portion25estore the feed bobbin25band the take-up bobbin25crespectively, therefore, the ink sheets25awound on the feed bobbin25band the take-up bobbin25care outwardly exposed on the space of the prescribed distance between the feed bobbin storage portion25dand the take-up bobbin storage portion25e. The ink sheets25aare constituted of those of three colors, i.e., Y (yellow), M (magenta) and C (cyan) ink sheets25a. As shown inFIGS. 5 and 9, the coupling portion25fis provided with the engaging portion25hengaging with the stop member27provided on the first side surface1aof the chassis1. As shown inFIG. 12, the ink sheet cartridge25is provided with helical compression springs25jregularly urging the ink sheet cartridge25mounted on the thermal transfer printer in the ejective direction along arrow A1inFIG. 5.

According to this embodiment, a slender groove portion (engaging portion)25iis provided on the upper surface of the coupling portion25fof the ink sheet cartridge25for engaging with the stop member27, as shown inFIGS. 9 and 10. This groove portion25iextends parallelly to the extensional direction (along arrow Q inFIG. 10) of the coupling portion25f. The width of the groove portion25iis rendered slightly larger than the thickness of the stop member27. When the stop member27is inserted into the groove portion25i, therefore, the groove portion25iengages with both surfaces of the stop member27as shown inFIG. 11.

The take-up reel24(seeFIG. 4) engages with the take-up bobbin25carranged in the take-up bobbin storage portion25eof the ink sheet cartridge25(seeFIG. 9), thereby taking up the ink sheets25awound on the take-up bobbin25. As shown inFIG. 4, the gear portion24aof the take-up reel24meshes with the swing gear21swinging along arrow X.

As shown inFIG. 4, further, the paper feed motor18driving the feed roller9and the take-up reel24is mounted on the motor bracket17through the motor gear18aand the intermediate gears22and23. The press member rotating motor19vertically rotating the head portion press members6and7is mounted on the motor bracket17. A small-diametral gear portion201aof the drive gear20ameshes with the gear portion6bof the head portion press member6as shown inFIG. 2, while a large-diametral gear portion202athereof meshes with a small-diametral gear201bof the intermediate gear20bas shown inFIG. 1. A large-diametral gear202bof the intermediate gear20bmeshes with the motor gear19aof the press member rotating motor19. Thus, driving of the press member rotating motor19is transmitted to the head portion press member6through the intermediate gear20band the drive gear20a.

A printing operation of the thermal transfer printer according to this embodiment is now described with reference toFIGS. 1,2,4,5and13to18.

In an initial state, the thermal transfer printer holds the head portion2bof the print head2at a position separated from the platen roller3, as shown inFIG. 13. At this time, the projection7bof the head portion press member7engages with the notch28cof the engaging portion28dof the spring fixing portion28bprovided on the head portion2b, thereby inhibiting the head portion2bfrom rotation along arrow D1inFIG. 13. The thermal transfer printer regularly urges the ink sheet cartridge25along arrow A1inFIG. 5, and inhibits the same from movement along arrow A1due to the engagement between the engaging portion25hof the ink sheet cartridge25and the engaging pawl26cof the stop portion26a, as shown inFIG. 5.

When the thermal transfer printer drives the press member rotating motor19(seeFIG. 4) from the initial state shown inFIG. 13, the driving force thereof is transmitted to the gear portion6aof the head portion press member6through the intermediate gear20b(seeFIG. 2) and the drive gear20a, thereby rotating the head portion press member6about the support rod5along arrow E1. At this time, the head portion press member7also rotates along arrow E1with the head portion press member6, since the head portion press members6and7(seeFIG. 2) do not idle with respect to the support rod5. The projection7bof the head portion press member7so rotates along arrow E1that the head portion2b, having been controlled through the projection7bnot to rotate along arrow D1, also rotates along arrow D1. Thus, the head portion2bmoves toward the platen roller3(press side), as shown inFIG. 13. The stop member27also rotates along arrow E1following the rotation of the head portion press members6and7, as shown inFIG. 14.

While the print head2moves to a press position shown inFIG. 15, the head portion press members6and7further rotate along arrow E1. Thus, the press portion6aof the head portion press member6presses the first end30aof the torsion coil spring30arranged on the spring holder28. Further, the press portion7aof the head portion press member7also presses the first end31aof the torsion coil spring31arranged on the spring holder28. At this time, the torsion coil springs30and31cause urging force, which in turn is transmitted to the head portion2bthrough the second ends30band31bof the torsion coil springs30and31respectively. Thus, the head portion2bis urged toward the platen roller30through the paper8and the Y ink sheet25a. The head portion2bgenerates heat, to melt ink of the Y ink sheet25aand transfer the same to the paper8.

As shown inFIG. 4, the thermal transfer printer drives the paper feed motor18to rotate the motor gear18amounted thereon along arrow F1, thereby rotating the feed roller gear10along arrow G1through the intermediate gears22and23. Thus, the feed roller9rotates along arrow G1following the rotation of the feed roller gear10(seeFIG. 4) as shown inFIG. 15, thereby carrying the paper8in a paper discharge direction (along arrow H1inFIG. 15). The swingable swing gear21(seeFIG. 4) swings along arrow X inFIG. 4, to mesh with the gear portion24aof the take-up reel24. Therefore, the gear portion24aof the take-up reel24rotates along arrow I1inFIG. 4, so that the take-up bobbin25ctakes up the Y ink sheet wound on the feed bobbin25b. Thus, the ink is continuously transferred from the Y ink sheet25ato the paper8.

As shown inFIG. 16, the stop member27rotates along arrow E1by about 63° from the initial position of the print head2following the rotation of the head portion press members6and7. In this state, the core of the stop member27is perpendicular. In printing, the stop member27engages with the groove portion25iof the ink sheet cartridge25, as shown inFIG. 16.

According to this embodiment, the thermal transfer printer inhibits the ink sheet cartridge25from movement in the ejective direction (along arrow A1inFIG. 5) not only through the stop portion26aprovided outside the second side surface1bof the chassis1but also through the stop member27provided inside the second side surface1bof the chassis1, due to the engagement between the stop member27and the groove portion25iof the ink sheet cartridge25. Also when the user manually operates the stop portion26aprovided outside the second side surface1bof the chassis1for ejecting the ink sheet cartridge25, therefore, the thermal transfer printer inhibits the ink sheet cartridge25from movement in the ejective direction (along arrow A1inFIG. 5) due to the engagement between the stop member27provided inside the second side surface1bof the chassis1and the groove portion25iof the ink sheet cartridge25.

Upon completion of printing of the Y (yellow) ink sheet25a, the thermal transfer printer drives the press member rotating motor19(seeFIG. 4) so that the driving force thereof is transmitted to the gear portion6aof the head portion press member6through the intermediate gear20b(seeFIG. 1) and the drive gear20a. Thus, the head portion press member6rotates about the support rod5along arrow E2inFIG. 17. At this time, the head portion press member7also rotates along arrow E2as shown inFIG. 17, since the head portion press members6and7(seeFIG. 2) do not idle with respect to the support rod5. The projection7bof the head portion press member7rotates along arrow E2to lift up the notch28cof the spring holder28of the print head2engaging with the projection7b, thereby rotating the head portion2bof the print head2along arrow D2. Thus, the head portion2bof the print head2separates from the platen roller3. As shown inFIG. 18, the stop member27rotates along arrow E2by about 18° following the rotation of the head portion press members6and7. According to this embodiment, the stop member27is still in engagement with the slender groove portion25iafter the head portion2bof the print head2separates from the platen roller3.

As shown inFIG. 4, the thermal transfer printer drives the paper feed motor18to rotate the motor gear18amounted thereon along arrow F2, thereby rotating the feed roller gear10along arrow G2through the intermediate gears22and23. Thus, the feed roller9rotates along arrow G2following the rotation of the feed roller gear10(seeFIG. 4) as shown inFIG. 17, thereby carrying the paper8in a paper feed direction (along arrow H2inFIG. 17) again. The swingable swing gear21(seeFIG. 4) swings along arrow Y inFIG. 4, to separate from the gear portion24aof the take-up reel24. Thus, the thermal transfer printer carries only the paper8in the paper feed direction without taking up the Y ink sheet25awound on the feed bobbin25bon the take-up bobbin25c.

Thereafter the thermal transfer printer performs operations similar to the above on the M and C ink sheets25a. When completely printing the Y, M and C ink sheets25a, the thermal transfer printer carries the paper8in the paper discharge direction (along arrow H1inFIG. 13). Then, the head portion2bof the print head2brotates to the initial position as shown inFIG. 13, thereby completing printing on the paper8. When the head portion2bof the print head2is on the initial position, the stop member27and the groove portion25iof the ink sheet cartridge25are in disengagement from each other, and only the stop portion26ainhibits the ink sheet cartridge25from movement in the ejective direction (along arrow A1inFIG. 5).

According to this embodiment, as hereinabove described, the stop portion26ais provided outside the chassis1while the stop member27engaging with the ink sheet cartridge25in printing is provided inside the chassis1so that the stop member27and the ink sheet cartridge25remain engaging with each other in the chassis1also when the user disengages the stop portion26aprovided outside the chassis1and the ink sheet cartridge25from each other in printing, whereby the thermal transfer printer can suppress ejection of the ink sheet cartridge25in printing. Consequently, the thermal transfer printer can suppress breakage of the ink sheets25a, and can prevent a failure resulting from entanglement of the ink sheets25atherein.

According to this embodiment, the stop member27is so provided inside the chassis1that the user can be inhibited from touching the stop member27, whereby the thermal transfer printer can prevent the second stop member27from application of a load in printing. Thus, the thermal transfer printer can prevent the members provided inside the chassis1from application of a load in printing, thereby suppressing reduction of printing quality.

According to this embodiment, the stop member27is mounted on the support rod5to be rotatable following rotation of the head portion press members6and7rotating the print head2in printing, whereby the stop member27can engage with the ink sheet cartridge25in printing without a dedicated drive source. Consequently, the thermal transfer printer can easily suppress ejection of the ink sheet cartridge25in printing.

According to this embodiment, the ink sheet cartridge25is provided with the groove portion25iengaging with both surfaces of the stop member27, whereby the thermal transfer printer can inhibit the ink sheet cartridge25from movement not only in the ejective direction (along arrow A1inFIG. 2) but also in a direction (along arrow P1inFIG. 2) opposite thereto. Thus, the thermal transfer printer can suppress reduction of printing quality resulting from misregistration in the direction (along arrow P1inFIG. 2) opposite to the ejective direction for the ink sheets25a.

According to this embodiment, the stop member27rotates following rotation of the print head2to engage with the groove portion25iwhen the print head2vertically rotates for printing the ink sheets25aof a plurality of colors, whereby the thermal transfer printer can suppress ejection of the ink sheet cartridge25also when the user disengages the stop portion26aand the ink sheet cartridge25from each other while the print head2separates from the platen roller3upon completion of printing in each color. Thus, the thermal transfer printer can suppress imperfect completion of printing resulting from ejection of the ink sheet cartridge25in an intermediate stage of printing in each color.

According to this embodiment, the groove portion25iprovide on the coupling portion25fof the ink sheet cartridge25is so located around a central portion between the take-up bobbin storage portion25eand the feed bobbin storage portion25dthat the stop portion27can engage with the groove portion25iaround the central portion between the take-up bobbin storage portion25eand the feed bobbin storage portion25d. Therefore, the stop member27can inhibit the ink sheet cartridge25from movement around the central portion between the take-up bobbin storage portion25eand the feed bobbin storage portion25dof the ink sheet cartridge25, whereby the thermal transfer printer can more stably inhibit the ink sheet cartridge25from movement as compared with a case of inhibiting the ink sheet cartridge25from movement on the side of the feed bobbin storage portion25dor the take-up bobbin storage portion25e.

According to this embodiment, the portion of the stop member27engaging with the ink sheet cartridge25is arcuately formed, whereby the stop member27can so easily partially engage with the engaging portion25ithat the thermal transfer printer can easily keep the stop member27and the groove portion25iin engagement also when the print head2vertically rotates in printing.

According to this embodiment, the groove portion25iof the ink sheet cartridge25has a slender form, whereby the thermal transfer printer can so increase the area of the groove portion25iengaging with the stop member27as to inhibit the stop member27from disengaging from the slender groove portion25iwhen the print head2rotates to separate from the platen roller3upon completion of printing in each color. Thus, the thermal transfer printer can easily engage the stop member27with the groove portion25ialso when the print head2separates from the platen roller3upon completion of printing in each color.

For example, while the aforementioned embodiment is applied to the thermal transfer printer, the present invention is not restricted to this but is also applicable to another image generating apparatus other than the thermal transfer printer.

While the groove portion is provided on one of the coupling portions of the ink sheet cartridge in the aforementioned embodiment, the present invention is not restricted to this but the groove portion may alternatively be provided on a position other than the coupling portion of the ink sheet cartridge. For example, the groove portion may be provided on the take-up bobbin storage portion.

While the groove portion engaging with the stop member is provided on one of the coupling portions of the ink sheet cartridge in the aforementioned embodiment, the present invention is not restricted to this but an engaging portion other than the groove portion may alternatively be provided on the ink sheet cartridge so far as the same can engage with the stop member for inhibiting the ink sheet cartridge from movement in the ejective direction. For example, a boss engaging with the stop member may be provided on the ink sheet cartridge. Further, the stop member may be provided in the form of a groove, and the ink sheet cartridge may be formed with a projecting portion engaging with the groove-shaped stop member.

While the angle of the arcuately formed portion of the stop member is set to about 40° in the aforementioned embodiment, the present invention is not restricted to this but the arcuately formed portion of the stop member may alternatively be at an angle other than 40°.

While the thermal transfer printer is provided with the arcuate stop member in the aforementioned embodiment, the present invention is not restricted to this but the thermal transfer printer may alternatively be provided with a stop member having a shape other than the arcuate shape so far as the same can engage with the ink sheet cartridge.