1. Field of the Invention
The present invention relates to a recording apparatus that transfers ink from an ink ribbon onto paper with a recording head on the basis of image information.
2. Description of the Related Art
A recording apparatus that forms an image (including letters and symbols) on a recording medium with a recording head on the basis of image information is used as a printer, a photocopier, a facsimile, or a scanner, or in a multifunction device or a system. As an example of such a recording apparatus, a thermal transfer recording apparatus that heats and transfers ink applied to an ink ribbon onto paper (a recording medium) with a recording head (thermal head) and thereby forms an image, may be used. In this thermal transfer recording apparatus, unlike other binary recording technologies, such as an ink jet recording apparatus, a pixel can have a wide range of gradation. Therefore, in step with the recent advancement of digital cameras, a thermal transfer recording apparatus has received much attention, particularly as a printer for a natural image.
In addition, there is known a system such that a printer is directly connected to an image pickup device, such as a digital camera. The printer can perform printing out without using a device that processes image information (such as a computer). Such a system makes it possible to print out the image information from a digital camera or a digital camcorder easily and photographically. Therefore, a thermal transfer recording apparatus has increasingly received much attention. Consumers want to carry a printer together with a digital camera, and compactness is an important selling point of a printer (recording apparatus).
As a method to reduce the size of a thermal transfer recording apparatus, a paper cassette containing paper and a ribbon cassette containing an ink ribbon are loaded adjacent one another in the apparatus body, and the wasted space is thereby reduced. Japanese Patent Laid-Open No. 2000-108442 discloses a printer in which a cassette for recording paper and a cassette for an ink ribbon are loaded so that they abut each other. FIGS. 9 to 11 show a common thermal transfer recording apparatus in which a paper cassette and a ribbon cassette are loaded so that they abut each other.
In FIGS. 9 to 11, the recording media loaded in the paper cassette 102 are cut sheets 101. One end of an ink ribbon 103 is fixed to a supply shaft 104 and the other end is fixed to a take-up shaft 105. The ink ribbon 103 is wound on the supply shaft 104 and/or the take-up shaft 105. The ribbon roll 103a on the supply shaft 104 is housed in a supply side ribbon chamber 106a, and the ribbon roll 103b on the take-up shaft 105 is housed in a take-up side ribbon chamber 106b. The supply side ribbon chamber 106a and the take-up side ribbon chamber 106b are joined by a joining member and constitute a ribbon cassette 106.
When recording is performed, a paper feed mechanism (not shown) separates a sheet P from the sheets 101 in the paper cassette 102 and conveys it to the space between the thermal head 108 and a platen roller 109 along a conveyance path (not shown). The sheet P is further conveyed so as to be nipped between a conveyance roller pair 107. The sheet P and the ink ribbon 103 are pressed against each other between the thermal head 108 and the platen roller 109. In synchronization with the conveyance of the sheet P and the ink ribbon 103, the thermal head 108 is driven on the basis of image information, ink is transferred onto the sheet P, and an image is thereby formed. In the case of color recording, the sheet P is reciprocated so that color inks applied to the ink ribbon 103 are transferred onto the sheet P one over another, and a color image is thereby formed. After the recording is completed, the sheet P is discharged from the apparatus body.
In
However, in the above conventional recording apparatus, with the consumption of the sheets 101, the empty space in the paper cassette 102 increases. This space is dead/wasted space. On the other hand, as for the ribbon cassette 106, there always is a space in each of the supply side ribbon chamber 106a and the take-up side ribbon chamber 106b, between the ribbon roll and the inner face of the ribbon cassette 106 from the start to the end of use of the ink ribbon 103. These spaces in the ribbon cassette 106 are also dead/wasted spaces. In conventional recording apparatus, such dead spaces cannot be eliminated nor reduced. Therefore, the space efficiency cannot be improved. This is an obstacle to reducing the size of the apparatus body.
The present invention provides a compact recording apparatus including a paper chamber capable of containing paper and a ribbon chamber containing an ink ribbon in a manner such that the ink ribbon on a supply shaft can be taken up onto a take-up shaft, by utilizing the dead spaces in the paper chamber and the ribbon chamber.
In an aspect of the present invention, a recording apparatus includes a paper chamber, a ribbon chamber, and a recording head. The paper chamber is capable of containing paper. The ribbon chamber is configured to contain an ink ribbon in a manner such that the ink ribbon on a supply shaft can be taken up onto a take-up shaft. The recording head is driven on the basis of an image signal and is configured to transfer ink from the ink ribbon onto the paper. The distance between the paper chamber and the rotation center of the take-up shaft is larger than the radius of a ribbon take-up portion of the take-up shaft and is smaller than the radius of a fully taken up roll of the ink ribbon.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
The embodiments of the present invention will now be described with reference to the drawings. In every figure, the same reference numerals designate the same or corresponding components.
In the ribbon cassette 6, a supply shaft 4 and a take-up shaft 5 are rotatably supported. The ink ribbon 3 is initially wound on the supply shaft 4 and is taken up onto the take-up shaft 5. When loaded with the paper cassette 2 and the ribbon cassette 6, the recording apparatus can perform recording. The paper cassette 2 has a paper chamber 2a formed therein. The paper chamber 2a contains a stack of sheets. The ribbon cassette 6 has a ribbon chamber 6a formed therein. The ribbon chamber 6a includes a supply side ribbon chamber 6b and a take-up side ribbon chamber 6c. The supply side ribbon chamber 6b contains a supply side ribbon roll 3a. The take-up side ribbon chamber 6c contains a take-up side ribbon roll 3b.
In
At this time, the sheet P and the ink ribbon 3 are pressed against each other by the thermal head 8 and the platen roller 9. By selectively driving a plurality of heating elements arranged on the thermal head 8, the ink applied to the ink ribbon 3 is transferred onto the sheet P, and an image is thereby recorded. In the case of color recording, the ink ribbon 3 has repeating sets of a plurality of color ink coatings, for example, yellow, magenta, and cyan ink coatings, each color ink coating having the same length. The sheet P is reciprocated as often as the number of ink colors through the image forming section. The color inks are transferred onto the sheet P one over another, and a color image is thereby formed. As described above, in the case of color recording, the ink ribbon 3 has repeating sets of a plurality of color ink coatings, each color ink coating having the same length. One of these sets is used per sheet. Therefore, normally, a predetermined number of sheets of the paper 1 are consumed in one-to-one correspondence with the same number of sets in the ink ribbon 3.
For the above-described recording apparatus, a pack containing a predetermined number of sheets and an ink ribbon having the same number of sets is distributed in the market and is provided for users. When recording (printing) is performed, a user opens the pack and loads the sheets and the ink ribbon into the recording apparatus. Both expendable materials are used up at the same time. When they are used up, the user opens a new pack and loads new ones. Therefore, unless a user opens different kinds of packs at the same time and mix up the content thereof, the remaining amount of the paper loaded in the recording apparatus always has a constant relation to the amount of taken up ink ribbon.
Next, the characteristic configuration and operation of the recording apparatus according to this embodiment will be described with reference to FIGS. 1 to 4. In this embodiment, when the paper cassette 2 and the ribbon cassette 6 are loaded in the apparatus body and therefore recording is possible, the take-up shaft 5 is disposed at a position such that the distance L between the paper chamber 2a and the rotation center of the take-up shaft 5 is larger than the radius r of the ribbon take-up portion 5b of the take-up shaft 5 and is smaller than the radius R of the fully taken up ribbon roll 3c. The radius r of the ribbon take-up portion 5b of the take-up shaft 5 means the radius of the portion 5b when the ink ribbon 3 is not yet taken up on the take-up shaft 5 at all. The radius R of the fully taken up ribbon roll 3c means the radius of the ribbon roll 3c on the take-up shaft 5 when the ink ribbon 3 is fully taken up onto the take-up shaft 5 from the supply shaft 4.
As shown in
Therefore, part of the paper chamber 2a and part of the ribbon chamber 6a (take-up side ribbon chamber 6c) of the ribbon cassette 6 overlap with each other in the area shown by a dotted line in
In addition, overlapping the paper chamber and the ribbon chamber as described above makes it possible to dispose the take-up side ribbon chamber 6c at a higher position compared to the conventional example of FIGS. 9 to 11. Therefore, the mechanisms of the image forming section, for example, the conveyance roller pair 7, the thermal head 8, and the platen roller 9 can also be disposed at a higher position. Disposing the components in such a manner makes it possible to reduce the size of the apparatus body 10 from the conventional size shown by a dashed line in
Next, a series of recording operations in this embodiment will be described with reference to
The ink ribbon 3 has repeating sets of a plurality of color ink coatings, for example, black, yellow, magenta, and cyan ink coatings, each color ink coating having the same length. The sheet P and the ink ribbon 3 are reciprocated the same number of times as the number of ink colors through the image forming section, and the recording operation (printing operation) is repeatedly performed. Thus, the color inks are transferred onto the sheet P one over another, and a color image is thereby formed. After the image formation, the sheet P is conveyed in the direction of the arrow and is then discharged from the apparatus body 10. Thus, a series of recording operations is completed.
The sheets P in the paper cassette 2 are consumed one at a time with the repetition of the recording operation. In the paper chamber 2a, the empty area enlarges by the sum of the thickness of the consumed sheets. In this embodiment, under any conditions, the height of the ribbon roll 3b from the bottom of the paper chamber 2a never exceeds the sum of the thickness of the consumed sheets. That is to say, three parameters: the thickness of a sheet P, the thickness of the ink ribbon 3, and the length of ink coating on the ink ribbon 3 used per sheet are appropriately determined. Therefore, even if the ribbon roll 3b comes into contact with the sheets P in the paper chamber 2a, the taking up of the ink ribbon 3 is not obstructed.
As shown in
Next, the recording apparatus of the second embodiment will be described with reference to
In this embodiment, the opening 2d is covered by a protective sheet 11. One end of the protective sheet 11 is fixed by adhesion on the paper outlet side of the opening 2d of the paper cassette 2. The protective sheet 11 is formed of a sheet material capable of elastic deformation (such as, for example, a resin or a plastics material) and can be displaced around the fixed portion as shown. With the entrance of the ribbon roll 3b into the paper cassette 2 due to the repeated recording operation (printing operation), the sheets 1 are pressed up by the ribbon roll 3b as shown in
In the first embodiment, the ink ribbon 3 is wound on the take-up shaft 5 with the ink coated surface facing inward. However, when the arrangement of the mechanisms in the apparatus body is restricted, it can be difficult to take up the ink ribbon 3 with the ink coated surface facing inward. In this embodiment, if the ink ribbon 3 is taken up with the ink coated surface facing outward, the protective sheet 11 can prevent ink from adhering to the sheets 1. In this case, after adhering to the protective sheet 11 from the ink ribbon 3, ink can re-adhere to the ribbon roll 3b. However, since the ink ribbon forming the ribbon roll 3b is a used ribbon, there is no problem.
In addition, in this embodiment, since the ribbon roll 3b is not directly in contact with the sheets 1, the lowermost sheet is not displaced due to friction with the rotating ribbon roll 3b. Therefore, when a paper feeding operation for the next recording is performed, a problem due to sheet displacement does not occur. As described above, the second embodiment provides the same advantageous effects as those in the first embodiment, and in addition, can eliminate problems due to direct contact between the sheets and the ink ribbon.
Although, in this embodiment, the protective sheet 11 is formed of a resin material, the protective sheet 11 may be formed of other materials, such as paper or aluminum foil. In addition, the shape of the protective sheet 11 and the method for attaching the protective sheet 11 are not limited. As long as the protective sheet 11 can prevent the contact between the sheets 1 and the ribbon roll 3b, the protective sheet 11 can be attached in a variety of ways. For example, instead of fixing one end of the protective sheet 11 to the paper cassette 2 as shown, a protective member movable between the sheets 1 and the ribbon roll 3b may be provided. Alternatively, a protective member may be attached to the ribbon cassette 6 or the apparatus body 10.
The third embodiment of
According to the above-described embodiments, a recording apparatus includes a paper chamber 2a containing paper 1 and a ribbon chamber 6a containing an ink ribbon 3 capable of being taken up. The paper 1 and the ink ribbon 3 are pressed against each other and conveyed. A thermal head 8 driven on the basis of image information transfers ink from the ink ribbon 3 onto the paper 1. The distance between the paper chamber and the rotation center of the take-up shaft 5 when recording can be performed is larger than the radius of the ribbon take-up portion of the take-up shaft 5 and is smaller than the radius of the fully taken up ribbon roll 3c. By overlapping the paper chamber and the ribbon chamber, the dead space can be reduced. By utilizing the dead spaces in the paper chamber and the ribbon chamber, a recording apparatus having a compact body can easily be provided. In the foregoing embodiments, the paper contained in the paper chamber is a stack of cut sheets. However, the present invention can be applied to a recording apparatus or a cassette having a paper chamber containing a roll of paper.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications, equivalent structures and functions.
This application claims the priority of Japanese Application No. 2005-340166 filed Nov. 25, 2005, which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | Kind |
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2005-340166 | Nov 2005 | JP | national |