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(11) | EP 0 573 969 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | A dye donor web loading apparatus for a thermal printer |
| (57) A dye donor web loading apparatus (10) is provided for a thermal printer having a
base (14) and a door (16). First and second guiding support assemblies (18) are attached
to the door (16) and spaced apart the length of a donor web spool. The first guiding
support assembly (18) has a first member movable between locked and unlocked positions
and biased towards the locked position. The second guiding support assembly has a
second member movable between locked and unlocked positions and biased towards the
locked position. The members snap onto the spool when the spool is properly inserted.
The members have tapered slots for receiving and guiding the donor spool. The members
may be color coded, or the spools may have different lengths, or the web may be positioned
differently on each spool, to prevent improper insertion of the spool. |
Technical Field
[0001] This invention relates generally to thermal printers, and, more particularly, to a dye donor web loading apparatus for mounting a donor web wound upon spools in a door of the thermal printer.
Background of the Invention
[0002] It is desirable to have a thermal printer in which it is easy to accurately load the dye donor ribbon. It is desirable to make the printer as easy to use as practical while being cost effective in the manufacturing process. Some thermal printers have disposable dye donor cartridges that mount in the printer. An example of a ribbon cassette is shown in U.S. Patent No. 4,768,039 which issued August 30, 1988 to Akutagawa et al. A disposable cartridge holds the dye donor spools and offers convenience of use because it is relatively easy to insert and remove the cartridge. This is especially true in instances where the cartridge is insertable only one way. While cartridges offer convenience, they are expensive and discarded after one use. To conserve resources, there have been attempts to make cartridges reusable. Unfortunately, attempts have failed because it is difficult to rewind dye donor in a cartridge at the point of use.
[0003] To eliminate the problems associated with cartridges, some printers have configurations that mount the donor spools in the print engine without the benefit of a cartridge. Examples of cartridgeless printing devices are disclosed in U.S. Patent Nos. 4,527,172 which issued July 2, 1985 to Nagashima et al., 4,639,739 which issued January 27, 1987 to Tsutumi, and 4,717,270 which issued January 5, 1988 to Tsutumi. There are other printers that mount the spool in the printer door, again without cartridges.
[0004] Where spools are used without cartridges, there are also problems that arise. Space is always a consideration and there is not always sufficient room for all hands to manipulate the spools, regardless of whether the spools are full or empty. This makes installing new donor spools, or removing used spools, a difficult task. The user is required to load one end first, push it to the side, and then load the other end, requiring a number of operations that users find inconvenient. The spool can be mispositioned on the drive elements and therefore completely inoperative, or may cause printing errors. Accordingly, it will be appreciated that it would be highly desirable to have a cartridgeless dye donor loading system that is simple to use and prevents incorrect insertion of the spools.
[0005] A problem with spool only systems is the requirement to push them to the side to load the spool which may cause the user to wrinkle the new donor causing print artifacts. When the spools are mounted in the top or cover of the printer, access is difficult for properly inserting the spools. There is also the risk of dropping the spools into the internal works of the printer or onto the floor while attempting to load the spools. Accordingly, it will be appreciated that it would be highly desirable to have a cartridgeless dye donor loading system that provides simple access to the spools.
Summary of the invention
[0006] The present invention is directed to overcoming one or more of the problems set forth above. According to one aspect of the present invention, a dye donor web loading apparatus for a thermal printer having a base and a door comprises a first and second guiding support assemblies attached to the door. The first guiding support assembly has a first member movable between locked and unlocked positions, and first means for biasing the member towards the locked position. A second guiding support assembly is spaced from the first guiding support assembly and is attached to the door. The second guiding support assembly has a second member that is movable between locked and an unlocked positions, and has second means for biasing the second member towards the locked position.
[0007] According to another aspect of the invention, a dye donor web loading apparatus for a thermal printer having a base and a door hingedly moveable between a closed position, at which the door abuts the base, and an open position, at which the door is swung away from the base, comprises a first guiding support member attached to the door and movable between a locked position and an unlocked position, and first means for biasing the first support member towards the locked position. A second guiding support member is spaced from the first member and attached to the door and movable between locked and unlocked positions while biased towards the locked position. The first and second members act in concert to load the web. A third guiding support member is attached to the door and movable between locked and unlocked positions while biased towards the locked position. A fourth guiding support member is spaced from the third member and is attached to the door and movable between locked and unlocked positions while biased towards the locked position. The third and fourth members act in concert to load the web.
[0008] The guiding support members have tapered slots for receiving and guiding the donor spool, and may be color coded to prevent improper insertion of the spool. Also, the spools may be of different lengths, or the web may be centered on one spool and off center on the other spool. The members snap onto the spool when the spool is properly inserted.
[0009] These and other aspects, objects, features and advantages of the present invention will be more clearly understood and appreciated from a review of the following detailed description of the preferred embodiments and appended claims, and by reference to the accompanying drawings.
Brief Description of the Drawings
[0010] Figure 1 is diagrammatical longitudinal sectional view of a preferred embodiment of a thermal printer with the cover open exposing dye donor web loading guide supports in accordance with the present invention.
[0011] Figure 2 is a somewhat enlarged, diagrammatic view of a spool being inserted into the guide supports of Figure 1 with some parts shown in section and some parts cut away.
[0012] Figure 3 is side view of a guide support similar to the view shown in Figure 2, but illustrating the guide support in the locked position.
[0013] Figure 4 is a left side view of the guide support member illustrated in Figure 3.
Figure 5 is a diagrammatic view illustrating the alignment of spools with portions of the spools having indicia.
[0014] Figure 6 is a diagrammatic view similar to Figure 5, but illustrating another preferred embodiment wherein the spools differ in length for correct insertion.
[0015] Figure 7 is a diagrammatic view similar to Figures 5 and 6, but illustrating another preferred embodiment wherein the dye donor web is offset from the center of one of the spools.
Detailed Description of the Preferred Embodiments
[0016] Referring to Figures 1-2, a loading apparatus 10 for loading a dye donor web 12 into a thermal printer is illustrated. The printer has a base portion 14 and a door or cover portion 16 that is hingedly connected to the base portion 14 and movable between a closed position and an open position. At the closed position, the door 16 abuts the base 14, and, at the open position, the door 16 is swung away from the base 14 forming an angle greater than about 90 degrees. The door 16 swings an arc greater than 90 degrees in moving from the closed position to the open position to thereby provide easy access for inserting a new donor web 12 and removing an expended donor web 14.
[0017] The dye donor web loading apparatus 10 includes a first guiding support member 18 attached to the door 16 and movable between a locked position and an unlocked position. The guiding support member 18 has a slot 20 therein that is dimensioned to receive an end portion 22 of a dye donor web spool 24. The slot 20 has a tapered portion 26 for guiding an end portion 22 of the spool 24. Preferably, the end portion 22 of the spool 24 is also slightly tapered. The dye donor web loading apparatus 10 also includes a first means 28 for biasing the first support member 28 toward the locked position. The first means 28 preferably includes a coiled spring 30 in contact with the first member 18 for biasing the first member 18 toward the locked position.
[0018] Referring to figures 1-4, the apparatus 10 includes a bracket 32 pivotally connected to the first guiding support member 18 and fastened to the door 16 of the thermal printer. The bracket 32 engages the first support member 18 to thereby limit travel of the support member 18 towards the locked position.
[0019] Still referring to Figures 1-4, the web loading apparatus 10 includes means 34 for detecting when the first guide support member 18 is in the locked position. The means 34 may include a microswitch 36 or other device to sense the position of the guide support member 18.
[0020] The dye donor web loading apparatus 10 includes a second guiding support member 38 that is spaced from the first guiding support member 18 and attached to the door 16. The second guiding support member 38 is movable between a locked position and an unlocked and works in concert with first guiding support member 18 to receive a dye donor web spool 24. As with the first support member 18, the second support member 38 is biased by a biasing means 40 toward the locked position.
[0021] Referring to Figures 1-7, just as the first and second guiding support members 18, 38 form a pair of members and act concert to load the web 12, so do third and fourth support members 42, 44. The third and fourth members 42, 44 are constructed in a similar manner to the first and second elements 18, 38 and include biasing means 46, and 48, respectively. The first pair of support members 18, 40 receives one spool 24a while the second pair of support members 42, 44 receives the other spool 24b so that the dye donor web 12 can be wound from one spool 24a to the other spool 24b as it traverses a path through the printer to effect thermal printing.
[0022] It can now be appreciated that there has been described a dye donor web loading apparatus 10 for a thermal printer that has a base 14 and a door 16 hingedly moveable between a closed position at which the door 16 abuts the base 14, and an open position at which the door 16 is swung away from the base 14 past the vertical position. A first guiding support member 18 is attached to the door 16 and is movable between a locked position and an unlocked position, and is biased towards the locked position by a coil spring 30. A second guiding support member 38 is spaced from the first member 18 a distance equal to the length of the spool to be placed therebetween, and is attached to the door 16 and movable between locked and unlocked positions while biased towards the locked position. The first and second members 18, 38 act in concert to load one end of the donor web 12. A third guiding support member 42 is attached to the door 16 and movable between locked and unlocked positions while biased towards the locked position. A fourth guiding support member 44 is spaced from the third member 42, and is attached to the door 16 and movable between locked and unlocked positions while biased towards the locked position. The third and fourth members 42, 44 act in concert to load the other end of the web.
[0023] The first and second guiding support members 18, 38 may be conveniently spaced from one another a different distance than the third and fourth guiding support members 42, 44 to accommodate supply and take-up spools of different lengths. Having the supply spool 24a longer or shorter than the take-up spool 24b prevents incorrect insertion of the spools caused by swapping the spools. Having different lengths also allows the web 14 to be centered on one spool but not the other to prevent swapping and incorrect insertion in the thermal printer.
[0024] The guiding support members are biased toward the closed or locked position and snap into the locked position when the spool is properly inserted to secure the spool in position for correct operation of the thermal printer. The guiding support members 18, 38, 42, 44 may be color coded along with the ends of the spools to give a visual indication of correct insertion orientation.
[0025] The guiding support members each have a slot dimensioned to receive an end portion of a dye donor web spool. The slots in the first and second guiding support members may have dimensions different from the slots in the third and fourth guiding support members to receive spools of different diameters or cross section. This construction prevents swapping of the supply and take-up spools. The slots may have tapered portions to aid in inserting the spools.
[0026] Each bracket is pivotally connected to its associated guiding support member and fastened to the door. It engages the member to thereby limit travel of the support member towards the locked position. A microswitch mounted on the door is activated by the member to detect when the member is in the unlocked position and to prevent printing from occurring until the web is properly installed.
[0027] Operation of the present invention is believed to be apparent from the foregoing description, but a few words will be added for emphasis. First, the door is opened past vertical to make the inside fully accessible. Then, a new dye donor web is installed by aligning one spool with the two slots in one guide assembly that face each other to receive the spool. The proper guide slots can be chosen by observing the indicia or color code, noting the alignment of the donor web on the spool, or noting the length of the spools, whichever applies. Where colors or indicia are used, these are matched. Where spool lengths are different, only one spool will fit each pair of guiding support members. And where the donor web is off center, both spools cannot be inserted unless so inserted correctly. The aligned spool is pushed into the facing slots thereby causing the guide members to unlock and move against the biasing springs. As the spool is pushed farther, the guide members spring back locking the spool in position. The other spool is inserted into its guide members the same way. The tapered ends of the spools act as self-centering devices to aid the alignment. The tapered ends also aid in removal of a used spool which is removed by pulling it straight out of the slots. If desired, one support member may be pushed aside to assist removal, but pushing is not necessary.
[0028] While the invention has been described with particular reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements of the preferred embodiment without departing from the invention. In addition, many modifications may be made to adapt a particular situation and material to a teaching of the invention without departing from the essential teachings of the present invention.
[0029] The present invention provides a cartridge free dye donor loading system that is simple to use and that prevents incorrect insertion of the spools. It also provides simple access to the spools for easy insertion and removal.
[0030] As is evident from the foregoing description, certain aspects of the invention are not limited to the particular details of the examples illustrated, and it is therefore contemplated that other modifications and applications will occur to those skilled the art. For example, while the donor spools, brackets and guide support members are preferably constructed of a synthetic resin, metal can be used. Also, the spools can be constructed of cardboard or other strong, durable material. It is accordingly intended that the claims shall cover all such modifications and applications as do not depart from the true spirit and scope of the invention.
[0031] The invention may be summarized as providing
a dye donor web loading apparatus for a thermal printer, said thermal printer having a base and a door moveable between a closed position and an open position, said apparatus comprising:
a first guiding support means; and
a second guiding support means spaced from said first guiding support assembly and attached to said door.
[0032] Preferred embodiments of the invention are disclosed in the claims and also the dependent claims, which should be read as depending not only on the specified claims, but on any other claim and combination thereof. The same is true for the following summary of the invention:
The invention may be summarized as follows:
[0033]
1. A dye donor web loading apparatus for a thermal printer, said thermal printer having
a base and a door hingedly moveable between a closed position at which said door abuts
said base and an open position at which said door is swung away from said base, said
apparatus comprising:
a first guiding support assembly attached to said door, said first guiding support
assembly having a first guiding support member that is movable between a locked position
and an unlocked position, and having a first means for biasing said support member
towards the locked position; and
a second guiding support assembly spaced from said first guiding support assembly
and attached to said door, said second guiding support assembly having a second guiding
support member that is movable between a locked position and an unlocked position,
and having a second means for biasing said second support member towards the locked
position, said door swinging an arc greater than 90 degrees in moving from the closed
position to the open position.
2. A dye donor web loading apparatus, as set forth in 1, wherein, at the locked positions of said first and second guiding support members, said first and second guiding support members are spaced a first preselected distance one from the other, and at the unlocked positions of said first and second guiding support members, said first and second guiding support members are spaced a second preselected distance one from the other.
3. A dye donor web loading apparatus, as set forth in 2, wherein said first preselected distance is less than said second preselected distance.
4. A dye donor web loading apparatus, as set forth in 1, wherein said dye donor web is wound about an elongated spool having an end portion with a preselected cross-sectional dimension, and said guiding support member has a slot dimensioned to receive said end portion of said spool.
5. A dye donor web loading apparatus, as set forth in 4, wherein said slot has a tapered portion for guiding said end portion of said spool.
6. A dye donor web loading apparatus, as set forth in 1, including a bracket fastened to said door and engaging said first guiding support member to thereby limit travel of said first guiding support member towards said locked position.
7. A dye donor web loading apparatus, as set forth in 6, wherein said bracket and said first guiding support member form a pivotal connection.
8. A dye donor web loading apparatus, as set forth in 1, including means for detecting when said first guide support member is in said locked position.
9. A dye donor web loading apparatus for a thermal printer, said thermal printer having
a base and a door hingedly moveable between a closed position at which said door abuts
said base and an open position at which said door is swung away from said base, said
apparatus comprising:
a first guiding support member attached to said door and movable between a locked
position and an unlocked position;
a first means for biasing said first support member towards the locked position;
a second guiding support member spaced from said first guiding support member and
attached to said door and movable between a locked position and an unlocked position;
a second means for biasing said second support member towards the locked position,
said first and second guiding support members acting in concert to load said web;
a third guiding support member attached to said door and movable between a locked
position and an unlocked position;
a third means for biasing said third support member towards the locked position;
a fourth guiding support spaced from said third guiding support member and attached
to said door and movable between a locked position and an unlocked position; and
a fourth means for biasing said fourth support member towards the locked position,
said third and fourth guiding support members acting in concert to load said web;
10. A dye donor web loading apparatus, as set forth in 9, wherein, said first and second guiding support members are spaced from one another a different distance than said third and fourth guiding support members.
11. A dye donor web loading apparatus, as set forth in 9, wherein, at the locked positions of said first and second guiding support members, said first and second guiding support members are spaced a first preselected distance one from the other, and at the unlocked positions of said first and second guiding support members, said first and second guiding support members are spaced a second preselected distance one from the other.
12. A dye donor web loading apparatus, as set forth in 9, wherein said first preselected distance is less than said second preselected distance.
13. A dye donor web loading apparatus, as set forth in 9, wherein said first, second, third and fourth guiding support members each have a slot dimensioned to receive an end portion of a dye donor web spool.
14. A dye donor web loading apparatus, as set forth in 13, wherein said slots in said first and second guiding support members have dimensions different from said slots in said third and fourth guiding support members.
15. A dye donor web loading apparatus, as set forth in 13, wherein each of said slots has a tapered portion.
16. A dye donor web loading apparatus, as set forth in 9, wherein said web is centered between said first and second guiding support members but not centered between said third and fourth guiding support members.
17. A dye donor web loading apparatus, as set forth in 9, including a bracket pivotally connected to said first guiding support member and fastened to said door and engaging said first guiding support member to thereby limit travel of said first guiding support member towards said locked position.
18. A dye donor web loading apparatus, as set forth in 9, including means for detecting when said first guiding support member is in said locked position, said means including a microswitch mounted on said door and activated by said first guiding support member.
19. A dye donor web loading apparatus, as set forth in 9, wherein said first, second, third and fourth guiding support members are color coded.
20. A dye donor web loading apparatus, as set forth in 9, wherein said door swings an arc greater than 90 degrees in moving from the closed position to the open position.
a first guiding support assembly attached to said door, said first guiding support assembly having a first guiding support member that is movable between a locked position and an unlocked position, and having a first means for biasing said support member towards the locked position; and
a second guiding support assembly spaced from said first guiding support assembly and attached to said door, said second guiding support assembly having a second guiding support member that is movable between a locked position and an unlocked position, and having a second means for biasing said second support member towards the locked position, said door swinging an arc greater than 90 degrees in moving from the closed position to the open position.
a first guiding support member attached to said door and movable between a locked position and an unlocked position;
a first means for biasing said first support member towards the locked position;
a second guiding support member spaced from said first guiding support member and attached to said door and movable between a locked position and an unlocked position;
a second means for biasing said second support member towards the locked position, said first and second guiding support members acting in concert to load said web;
a third guiding support member attached to said door and movable between a locked position and an unlocked position;
a third means for biasing said third support member towards the locked position;
a fourth guiding support spaced from said third guiding support member and attached to said door and movable between a locked position and an unlocked position; and
a fourth means for biasing said fourth support member towards the locked position, said third and fourth guiding support members acting in concert to load said web;