Optical writing printer head, print apparatus, and image processing system

Abstract

 A head apparatus, a print apparatus, a system of a print apparatus and an image processing apparatus providing cooling of a substrate and an aperture of the head are disclosed. In order that heat accompanying flashing light emitted by light emitting diodes 12b, 12c, and 12d does not decrease the quantity of light from the light emitting diodes and thus change the quality of an image and does not raise the temperature of a substrate 12a to the melting point of the plastic forming a carriage 9; the substrate 12a is preferably formed of a metal plate having high heat conductivity, and a heat radiating means for radiating heat of the substrate 12a is provided. The heat radiating means for radiating the heat of the substrate 12a preferably comprises air holes 31 opened on both sides of a box-shaped substrate supporting portion 9a of the carriage 9 in the travelling direction of the carriage. With regard to a heat radiating means for radiating the heat of the aperture 29, the aperture 29 is preferably formed in a metal plate having high heat conductivity. The aperture 29 is supported by the carriage 9, and the heat of the aperture 29 is radiated by the heat radiating means provided for radiating the heat of the substrate 12a.

Description

[0001] The present invention relates to a head apparatus for outputting an image, a print apparatus including the head apparatus, and an image processing system including the print apparatus.

[0002] A conventional head apparatus of a print apparatus is structured such that light is emitted by a light emitting diode formed on a substrate provided on a carriage, which is guided by a carriage guide and reciprocated by a motor. The light is irradiated onto print paper, after the light spot diameter is decreased by a pinhole aperture. In the conventional head apparatus, there is a fear that, due to heat accompanying the flashing light emitted by the light emitting diode, the quantity of light emitted by the light emitting diode may decrease and thus change the quality of the final image. In particular, the temperature of the substrate and the aperture may rise above the melting point of the plastic which is used to form the carriage, (about 130°C, for example) to melt or change the shape of a substrate supporting portion of the carriage, leading to change in the substrate supporting state, and further, heat irradiation from the aperture may cause colour change or colour development of the print paper.

[0003] According to one aspect of the present invention, there is provided an optical writing printer head characterised by comprising: a carriage for reciprocating relative to print paper; a light emitting element provided on said carriage for exposing said print paper; an aperture having a pinhole for restricting an exposure dot size of said light emitting element; and a heat radiating means for radiating heat generated by said light emitting element.

[0004] According to another aspect of the present invention there is provided an optical writing printer head characterised by comprising: a carriage for reciprocating relative to print paper; a light emitting element for exposing said print paper and provided on a substrate attached to said carriage and formed of a metal plate having high heat conductivity; an aperture formed of a metal plate having high heat conductivity and having a pinhole for restricting an exposure dot size of said light emitting element; and a heat radiating means for radiating heat generated by said light emitting element.

[0005] Preferably, the present invention provides an optical writing printer head characterised in that the heat radiating means for radiating heat generated by the light emitting element has air holes opened on both sides of a box-shaped substrate supporting portion of the carriage in the travelling direction of the carriage.

[0006] Preferably, the present invention provides an optical writing printer head characterised in that the heat radiating means for radiating heat generated by the light emitting element has heat radiating fins attached to the rear surface of the substrate and made of metal having high heat conductivity.

[0007] Preferably, the present invention provides an optical writing printer head characterised in that the heat radiating means for radiating heat generated by the light emitting element has a heat transferring body made of metal having high heat conductivity, one end thereof being attached to the rear surface of the substrate, and the other end thereof being in slidable contact with the carriage guide.

[0008] Preferably, the present invention provides an optical writing printer head characterised in that the heat transferring body is a leaf spring.

[0009] Preferably, the present invention provides an optical writing printer head characterised in that the heat radiating means for radiating heat generated by the light emitting element is the aperture formed of the metal plate having high heat conductivity supported by the carriage.

[0010] Preferably, the present invention provides an optical writing printer head characterised in that the heat radiating means for radiating heat generated by the light emitting element is the aperture formed of the metal plate having high heat conductivity supported through a heat insulating material by the carriage and is in slidable contact with the carriage guide.

[0011] Further, the present invention provides a print apparatus characterised by making the light emitting element of an optical writing printer head emit light, decreasing the light diameter by the pinhole of the aperture, and irradiating the light onto print paper to generate an image on the print paper and in which heat radiating means are provided for radiating heat generated by said light emitting element.

[0012] Further, the present invention provides an image processing system characterised by connecting a print apparatus to an image processing apparatus, and exchanging image signals between the image processing apparatus and the print apparatus, to generate an image on the print paper, in which the print apparatus includes a light emitting element and heat radiating means for radiating heat generated by the light emitting element.

[0013] Embodiments of the present invention will now be described by way of further example only and with reference to the accompanying drawings, in which:-

Fig. 1 is a plan view illustrating an image processing system of substantially the actual size having a print apparatus and an image processing apparatus according to a first embodiment of the present invention;

Fig. 2 is an enlarged sectional view of the print apparatus of Fig. 1 showing a side of the apparatus;

Fig. 3 is a sectional view of the print apparatus of Fig. 1 seen from the side where print paper is discharged;

Fig. 4 is an enlarged sectional view illustrating a main part of a carriage guided by a carriage guide and a head apparatus supported by the carriage;

Fig. 5 is an enlarged sectional view showing a main part of an image processing system having a print apparatus and an image processing apparatus according to a second embodiment of the present invention; and

Fig. 6 is an enlarged sectional view showing a main part of an image processing system having a print apparatus and an image processing apparatus according to a third embodiment of the present invention .

[0014] First, the schematic structure of an image processing system having a print apparatus and an image processing apparatus according to a first embodiment of the present invention is described with reference to the drawings.

[0015] As shown in Fig. 1 to Fig. 3, in the system, when a power switch (which is not shown) is turned on, image data stored in an image processing apparatus B is selected, and a print image output switch (which is not shown) is turned on, a print apparatus A carries out printing.

[0016] When the power switch is turned on, a motor 1 rotates by a predetermined number of rotations in a direction opposite to the normal direction of rotation of the hands of a clock. The rotation of the motor 1 is transmitted, through a train 2 of gears on the side of the motor and a train 3 of gears on the side opposite to the motor, to a mechanism 8 with a winding belt thereon provided on a carriage guide 7. As a result, a carriage 9 which is engaged with and guided by the carriage guide 7 reciprocates and travels to a home position. When the carriage 9 returns to the home position, the motor 1 stops its rotation.

[0017] Further, here, a bar code sensor 11 provided on a bracket 30 for attaching sensors reads a bar code C1 attached to a cassette C to specify the kind of print paper P contained in the cassette C. In printing, according to the kind of print paper identified here, the intensity or irradiation time of light from light emitting diodes 12b, 12c, and 12d, forming a head provided on the carriage 9, is controlled.

[0018] Next, when a print image output switch (not shown) is turned on; first, the motor 1 rotates in the normal direction of rotation of the hands of a clock to feed the print paper P by rotating a pickup roll 4 and feed rolls 5 and 13 through the gear trains 2 and 3. A paper feed confirming sensor 14 provided on the carriage 9 and located on the downstream side of the feed roll 5 senses the front edge of the print paper P.

[0019] When the paper P is sensed, the motor 1 stops its rotation for a time, and immediately after that, rotates in the direction opposite to the direction of rotation of the hands of a clock. This counterclockwise rotation makes the carriage 9 reciprocate through the mechanism 8 with a winding belt thereon. At the same time, a linear sensor 10 provided on the bracket 30 for attaching sensors of the carriage 9 reads the graduations of a linear scale 23 to detect the position of the travel.

[0020] At the same time as the reciprocation of the carriage 9, the light emitting diodes 12b, 12c, and 12d forming the head formed on a substrate 12a provided on the carriage 9 emit flashing light corresponding to the image data input from the image processing apparatus B. The light is, after the light diameter is decreased by a pinhole of an aperture 29, irradiated onto the print paper P to harden or cure microcapsules which receive light of predetermined wavelengths.

[0021] While a circulating pin 15 makes a U-turn from a position b to a position c (fig. 1), and while it makes a U-turn from a position d to the home position a, a cam 16 presses down a cam follower 17 by a small amount, and the feed rolls 5 and 13 in conjunction with pinch rolls 6 and 24 feed the print paper P by about 0.2 mm. On the other hand, while the circulating pin 15 moves linearly from the home position a to the position b, and while it moves linearly from the position c to the position d, the cam 16 releases the cam follower 17 from being pressed down. Thus, a platen 19 is lifted up by a spring 18 and a rolling roller 20 effectively pressurises the print paper P as if a straight line is drawn to selectively collapse only microcapsules which did not receive light of the predetermined wavelengths and thus did not cure. These actions are repeated to selectively collapse microcapsules over the whole surface of the print paper P.

[0022] The print paper P passes between a heater 21 and a leaf spring 22. Here, colour developing material which comes into contact with an image receiving layer as a result of the collapsed microcapsules is slidably contacted with the paper and is heated, and colour developing is facilitated instantaneously to generate an image.

[0023] The carriage guide 7 has linearity of high accuracy and is formed in a channel-shape (Fig. 4). Its ribs on both sides are held by channel portions on both sides of the carriage 9. The substrate 12a is precisely positioned with respect to the carriage 9. The light emitting diodes 12b, 12c, and 12d are formed together with circuit wirings on an insulating layer 12e formed on the substrate 12a, and are connected with the circuit wirings by bonding. The circuit wirings are connected with flexible printed wirings.

[0024] Reference numerals 25, 26, 27, and 28 denote a controller, a battery, a chassis, and a case, respectively.

[0025] In particular, in the print apparatus according to the present invention, in order to avoid a situation where, due to heat accompanying the flashing light emitted by the light emitting diodes 12b, 12c, and 12d, the quantity of light from the light emitting diodes decreases to change the quality of an image, and the temperature of the substrate 12a rises to the melting point of the plastic forming the carriage 9 (about 130°C, for example) such that, unless cooled, melting and change of shape of the substrate 12a and a substrate supporting portion of the carriage 9 and the aperture occurs; the substrate 12a is formed of a metal plate having high heat conductivity, and a heat radiating means for radiating heat from the substrate 12a is provided.

[0026] Fig. 4 is an enlarged sectional view illustrating a main part of the carriage 9 guided by the carriage guide 7 and a head apparatus 12 supported by the carriage 9.

[0027] In this embodiment, the substrate 12a is formed of a metal plate having high heat conductivity such as an aluminium plate, a stainless steel plate, a nickel plate, or the like.

[0028] The heat radiating means for radiating the heat of the substrate 12a comprises air holes 31 opened on both sides of a box-shaped substrate supporting portion 9a of the carriage 9 in the travelling direction of the carriage. When the carriage 9 travels, air in the print apparatus circulates via the air holes 31 through the inner space of the box-shaped substrate supporting portion 9a to come into contact with and cool the rear surface of the substrate.

[0029] Further, with regard to a heat radiating means for radiating the heat of the aperture 29, the aperture 29 is formed of a metal plate having high heat conductivity such as an aluminium plate, a stainless steel plate, a nickel plate, or the like. The aperture 29 is supported by the carriage 9, and the heat of the aperture 29 is radiated by the heat radiating means provided for radiating the heat of the substrate 12a.

[0030] Accordingly, cooling by airflow can achieve a temperature at which the quantity of light from the light emitting diodes does not decrease and the substrate supporting portion 9a and the aperture 29 does not melt or get soft.

[0031] Fig. 5 is an enlarged sectional view illustrating a main part of an image processing system having a print apparatus and an image processing apparatus according to a second embodiment of the present invention. Fig. 5 corresponds to Fig. 4, and identical numerals designate identical components.

[0032] In this embodiment, the substrate 12a is formed of a metal plate having high heat conductivity such as an aluminium plate, a stainless steel plate, a nickel plate, or the like.

[0033] The heat radiating means for radiating the heat of the substrate 12a is provided as a complex of two heat radiating means. A first heat radiating means comprises air holes 31 opened on both sides of a box-shaped substrate supporting portion 9a of the carriage 9 in the travelling direction of the carriage. A second heat radiating means comprises heat radiating fins 32 attached to the rear surface of the substrate and made of metal having high heat conductivity such as an aluminium plate, a stainless steel plate, a nickel plate, or the like.

[0034] Further, with regard to a heat radiating means for radiating the heat of the aperture 29, the aperture 29 is formed of a metal plate having high heat conductivity such as an aluminium plate, a stainless steel plate, a nickel plate, or the like. The aperture 29 is supported by the carriage 9, and the heat of the aperture 29 is radiated by the heat radiating means provided for radiating the heat of the substrate 12a.

[0035] Accordingly, when the carriage 9 travels, air in the print apparatus circulates via the air holes 31 through the inner space of the box-shaped substrate supporting portion 9a to cool the heat radiating fins 32. Thus, cooling by airflow can achieve a temperature at which the quantity of light from the light emitting diodes does not decrease and the substrate supporting portion 9a and the aperture 29 do not melt or get soft.

[0036] As a modification of this embodiment, the substrate supporting portion 9a of the carriage 9 may be formed to be rib-shaped rather than box-shaped and the heat radiating fins 32 may be positioned outside the substrate supporting portion 9a.

[0037] Fig. 6 is an enlarged sectional view illustrating a main part of an image processing system having a print apparatus and an image processing apparatus according to a third embodiment of the present invention. Fig. 6 corresponds to Fig. 4, and identical numerals designate identical components.

[0038] In this embodiment, the substrate 12a is formed of a metal plate having high heat conductivity such as an aluminium plate, a stainless steel plate, a nickel plate, or the like.

[0039] The heat radiating means for radiating the heat of the substrate 12a is provided as a complex of three heat radiating means. A first heat radiating means comprises air holes 31 opened on both sides of a box-shaped substrate supporting portion 9a of the carriage 9 in the travelling direction of the carriage. A second heat radiating means comprises heat radiating fins 33 attached to the rear surface of the substrate and made of metal having high heat conductivity such as an aluminium plate, a stainless steel plate, a nickel plate, or the like. A third heat means comprises the heat radiating fins 33 which serves also as a heat transferring body having a spring function and is in slidable contact with the carriage guide to press against the carriage guide.

[0040] Accordingly, when the carriage 9 travels, air in the print apparatus circulates via the air holes 31 through the inner space of the box-shaped substrate supporting portion 9a to cool the heat radiating fins 33. The heat radiating fins 33 transfer heat from the substrate 12a to the carriage guide 7. Thus, cooling by airflow can achieve a temperature at which the quantity of light from the light emitting diodes does not decrease and the substrate supporting portion 9a and the aperture 29 do not melt or get soft. In addition, the heat radiating fins 33 are in slidable contact with the carriage guide 7 to absorb the backlash of the carriage 9.

[0041] As described above, according to a head apparatus, a print apparatus, and an image processing system of the present invention, since a substrate and an aperture can be cooled, cooling to a temperature at which the quantity of light from a light emitting diode does not decrease and a substrate supporting portion of a carriage and the aperture do not melt or get soft can be achieved. Therefore, abnormal heating of a head can be avoided, the fear of thermal metamorphosis is avoided to assure long operating life, and metamorphosis of print paper due to heat radiation from the aperture can be avoided.

Claims

1. An optical writing printer head comprising:

a carriage for reciprocating relative to print paper;

a light emitting element provided on said carriage for exposing said print paper;

an aperture having a pinhole for restricting an exposure dot size of said light emitting element; and

a heat radiating means for radiating heat generated by said light emitting element.

2. An optical writing printer head comprising:

a carriage for reciprocating relative to print paper;

a light emitting element for exposing said print paper and provided on a substrate which is attached to said carriage and which is formed of a metal plate having high heat conductivity;

an aperture formed of a metal plate having high heat conductivity and having a pinhole restricting an exposure dot size of said light emitting element; and

a heat radiating means for radiating heat generated by said light emitting element.

3. An optical writing printer head as claimed in claim 1 or claim 2, wherein said heat radiating means for radiating heat generated by said light emitting element has air holes opened on both sides of a box-shaped substrate supporting portion of said carriage in the travelling direction of said carriage.

4. An optical writing printer head as claimed in claim 2, wherein said heat radiating means for radiating heat generated by said light emitting element has heat radiating fins attached to the rear surface of said substrate and is made of metal having high heat conductivity.

5. An optical writing printer head as claimed in claim 2 or claim 4, wherein said heat radiating means for radiating heat generated by said light emitting element has a heat transferring body made of metal having high heat conductivity, one end thereof being attached to the rear surface of said substrate, and the other end thereof being in slidable contact with a carriage guide.

6. An optical writing printer head as claimed in claim 5, wherein said heat transferring body is a leaf spring.

7. An optical writing printer head as claimed in any one of claims 2 to 6, wherein said heat radiating means for radiating heat generated by said light emitting element is said aperture and which is formed of a metal plate having high heat conductivity.

8. An optical writing printer head as claimed in any one of claims 2 to 6, wherein said heat radiating means for radiating heat generated by said light emitting element is said aperture and which is formed of a metal plate having high heat conductivity and supported through a heat insulating material by said carriage, and is in slidable contact with a carriage guide.

9. A print apparatus having an optical writing printer head as claimed in any one of claims 1 to 8.

10. An image processing system connecting a print apparatus as claimed in claim 9 to an image processing apparatus, and exchanging image signals between said image processing apparatus and said print apparatus, such that an image is generated on the print paper.

Drawing