JPS63270184A - Thermal transfer copying machine - Google Patents

Abstract

PURPOSE:To prevent the stain on the surface of a roller, by a method wherein, a copying paper guide adjustable according to the size of a copying paper is provided at a port for inserting the copying paper to a printing part, and the sliding position of this guide is electrically detected to control the printing range of a thermal head. CONSTITUTION:With the sliding action of a copying paper guide 22, the action of the copying paper guide 22 is transmitted to a slide volume through a reducing mechanism. The value of resistance of the slide volume is electrically detected to provide approximately 5mm non-printing parts 81 on the both sides in a width direction according to the dimension of the copying paper guide 22. Corresponding to the leading end part of a copying paper 12 and to the paper width set by the copying paper guide 22, respectively non-printing parts 80, 81 are formed so as to be at least the order of 5mm. With an original 3 larger in width than the copying paper 12, the non-printing parts 81 on the both sides of the copying paper 12 prevent that the heat generation of a thermal head 50 at a part where the copying paper 12 is absent results in the transfer of unwanted ink to a transfer roller 59.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention includes a thermal transfer type printing unit using an edge-type thermal head and a thermal ink sheet, and an image sensor unit that reads original images. The present invention relates to a thermal transfer copying device that copies images onto plain paper.

(Conventional Example) In recent years, various types of copying devices have been realized and become popular. In general, direct printing type copying machines that use surface-treated paper such as thermosensitive coloring paper, and electrostatic type electrophotographic copying machines that use plain paper are well known.

There is an electrophotographic copying machine as a device that makes copies using plain paper without surface treatment, in which mechanisms such as charging, exposure, development, transfer, and cleaning are arranged around a photoreceptor drum made of selenium, etc. After the surface of the rotating photoreceptor drum is charged, the irradiated light image of the original is sequentially exposed to slits using optical means such as mirrors and lenses, and the latent image is developed into a visible image with toner, and this toner image is synchronized. At the same time, the copy paper on which the toner image has been transferred is fixed under heat and pressure to obtain a copy.

(Problems to be Solved by the Invention) However, although the above-described direct printing type copying apparatus has a simple configuration and can be downsized, it cannot use plain paper.

Further, in an electrophotographic copying apparatus that can use plain paper, a certain amount of volume is required because the optical system such as mirrors and lenses is moved to perform slit exposure. For this reason, there is a limit to the reduction in size of the configuration, making it difficult to make the device more compact. moreover.

In order to heat and fix the toner image, it is necessary to install a fixing device having a heat source of about IKW, which causes an increase in the consumed IR power and an increase in the internal temperature of the machine.

Therefore, it was necessary to provide a preheat control means to reduce power consumption and an exhaust fan to discharge the heated air to the outside of the machine.

Furthermore, since fine powder toner is used for development, the toner powder is scattered inside the machine, contaminating the interior of the machine, and having an adverse effect on copied images. Therefore, in order to obtain stable copies of high quality, various problems have occurred, such as the need for maintenance work to periodically clean the scattered toner powder.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a thermal transfer copying apparatus that is compact, lightweight, and does not require maintenance as in conventional apparatuses.

(Means for Solving the Problems) In order to solve the above problems, the thermal transfer copying apparatus of the present invention includes a thermal transfer printing means using a thermal head and a thermal ink sheet, and a copy paper insertion slot for copying. A copy paper guide that can be adjusted according to the paper size is provided, and the color of the sliding of the copy paper guide is electrically detected to control the printing range of the thermal head.

(Function) According to the present invention, with the above-described configuration, the original image read by the image sensor is printed by the thermal head via the heat-sensitive ink sheet, and can be copied onto plain paper without surface treatment. .

In addition, by electrically detecting the sliding position of the copy paper guide and controlling the printing range, even if the original is larger than the copy paper size, it will not be printed on the surface outside the copy paper range of the roller. will not contaminate the surface.

(Example) An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a thermal transfer copying apparatus according to an embodiment of the present invention. In FIG. 1, there is a document platen glass 2 on the front side of the main body 1 on which a document to be copied is placed, and a document platen is used to press the document 3 placed on top of the document platen glass 2 so as to bring it into close contact with the document platen glass 2. A cover 4 is supported so as to be openable and closable using a back side 5 as a fulcrum. JJX
The platen glass 2 is arranged to be horizontally long when viewed from the front so that an A4 size original can be placed horizontally. On the rear side of the main body 1, a printing section 10 is provided for copying an image onto copy paper.

The print section 10 is first provided with a copy paper insertion slot 11 for inserting copy paper.
Insert one end of 2. The inserted copy paper 12 is held leaning against the guide M13 so that it does not fall down and come out from the insertion slot 11. Guide lid 1
3 is hingedly supported at the innermost position of the main body 1,
It can be opened and closed.

The guide lid 13 can be closed when the main body 1 is not used to cover the copy paper insertion slot 11 and the like. .

A copy paper output port 14 is located in front of the copy paper insertion port 11.
The guide plate 15 that forms the opening is provided with an opening of
As shown in FIG.
It is tilted so that it changes by more than 1°. Copy paper 1
2 can use up to the maximum size of A4 size paper, and the A4 size paper is fed in the longitudinal direction and comes out after being copied upward from the copy paper output [co 14]. Copy paper 1 coming out from copy paper outlet 14
2 is printed and ejected in an orientation that allows you to see the printed copy image when viewed from the front side, and if the copy paper is paper with low rigidity, it will fall toward the copy paper insertion slot ll side. ing. Therefore, the person making the copy can perform the copying operation while always checking the printed surface from the front side. In this embodiment, the document 3 is placed at the front left end 20 of the document table glass 2.
The copy paper 12 is set so as to match the right edge 21 of the copy paper insertion slot 11.

When copying onto paper having a width narrower than A4 size, a copy paper guide 22 slidably provided in the copy paper insertion slot 11 is slid to match the width of the copy paper.

A start button 231 is provided on the top surface of the main body 1, and a power switch 24 is provided on the left side surface of the main body.

FIG. 2 is a cross-sectional view of an image sensor unit provided under the document table glass 2. As shown in FIG.

In the image sensor unit 30, a sensor main body 33 is placed on a sensor base 32 which is slidably guided by a guide shaft 31 fixed to the main body 1.

The sensor body 33 includes an illumination LE for illuminating the original.
A D array 34, a light converging fiber lens 35 for forming and projecting an optical image of the original at the same magnification, and a contact type image sensor 36 provided on the imaging plane of the original image are attached.

If the positional relationship between the document 3 placed on the document platen glass 2 and the contact image sensor 36 is not set correctly, the optical image projected onto the contact image sensor 36 will be out of focus, resulting in a contact image. An appropriate output signal will not be obtained from the sensor 36.

In this embodiment, in order to accurately determine the distance between the document surface and the contact image sensor 36, rollers 37 are provided at the front and back ends of the sensor body 33, and the rollers 37 are connected to the sensor base 33. The sensor body 33 is pushed upward by a compression spring 38 provided between the sensor body 33 and the sensor body 33 so as to come into contact with the lower surface of the document table glass 2 and slide while rotating. Therefore, if the thickness of the original platen glass 2 is kept constant, the copy surface of the original placed on the original platen glass 2 and the contact image sensor 36 can always be kept constant.

FIG. 3 is a perspective view showing a method of driving the image sensor unit. A guide shaft 31 is fixed along the longitudinal direction of the document platen glass 2, and the image sensor unit 30 is guided by the guide shaft 31.

The belt 4 slides on the lower surface of the document platen glass 2 with the roller 37 and moves left and right by being pulled by the fixed end 41 with the belt 40.
0 is stretched between the left and right ends of the main body 1, and is driven by the rotation of a pulse motor 42. Image sensor unit 30
is driven by a pulse motor 42 to reciprocate between the origin switch 43 and the end point switch 44. The power supply to the LED array 34 of the image sensor unit 30 or the output from the image sensor 36 is connected to the main body side by a flat wire 39.

As shown in FIG. 4, the end face type thermal head 50 is mounted substantially upward from the bottom of the substrate of the main body 1.

Thermal heads have traditionally been used in thermal recording type facsimile machines, electronic typewriters, word processors, computer printers, etc. due to their features such as being maintenance-free, noiseless, and inexpensive.However, the thermal heads traditionally used are flat type. This is called a printed circuit board on one side of a flat board.

Each circuit element 1,1- has a heating element section in which fine heating elements of, for example, 8 dots are arranged in a row, and although it has the advantage of being easy to manufacture due to its flat layout, the area occupied by the thermal head is small. This is not desirable in terms of making the device more compact.

On the other hand, the thermal head 50 used in this embodiment is of the so-called end-face type, and as shown in FIG.
A glass glaze layer is formed on 2, and a heating resistor film is formed on the glass glaze layer on the end face 51 of m-, and the heating resistor film is connected to the circuit element 60 on the side surface through an electrode film. .

In this embodiment, the heating element formed on the end face 51 is composed of heating elements divided into 8 dots per 1 m over a 210I width of A4 size. However, it is not necessarily necessary to have the same length as the paper width, but it is sufficient if the length is the same as the image forming dimension on the paper. The surface of the heating element is protected by a wear-resistant protective film. The edge type thermal head has a convex heating element surface and has good thermal transfer characteristics.
It has the following characteristics: good linearity of the heating element forming surface, uniform print density, and compact head.
As shown in FIG.
4 is placed. A thermal ink sheet 55 is wound around the supply shaft 53 with its thermal ink surface facing outward.
This thermal ink sheet 55 is under tension on the lower side with a metal weight shaft 56, and the thermal head 5
0 to the end face 51 of the heating element. As shown in FIG. 5, the end face 51 of one heating element is pressed from above by a transfer roller 59 made of a rubber material and held by a roller frame 58 that can be opened and closed about a fulcrum 57. The transfer roller 59 has a length of 220 cm, a diameter of 20+ nm at the center, and a diameter of 0.15 nm at both ends.
■It has a small tassel-like shape. The diameter 20- is the range of 70 in the center, and the diameter 19.85 at both ends from that position.
The part marked - is a finish with a straight taper. By making the transfer roller 59 into a cone shape and pressing both ends with springs weighing about 1.2 kg on each side, the adhesion between the transfer roller 59 and the end surface 51 of the heating element is improved, and uniform density can be obtained over the entire width. It will be done.

Further, the cylindrical transfer roller 59 also serves to prevent wrinkles that tend to occur on the thermal ink sheet 55 and the copy paper 12.

Note that the shape of the cylindrical transfer roller is such that its tapered portions are connected by straight lines, but in this example, connecting them with straight lines was more effective against wrinkles than connecting them with curves.

Immediately to the left of the contact surface of the transfer roller 59 on the end face 51 of the heating element, a blade 61 made of a plastic material is fixed, the details of which are shown in FIG.

The heat-sensitive ink sheet 55 that has passed through the heating element end face 51 is wound up on the winding shaft 54 so that the heat-sensitive ink surface is on the inside. As shown in FIG. 6, the edge 62 of the blade 61 is in the tangential direction of the transfer roller 59 which is in pressure contact with the end face 51 of the first heating element, and is located approximately 7 wIIIXa from the contact position on the downstream side in the copy paper feeding direction. Therefore, copy paper 1
2 is sent into the gap between the transfer roller 59 and the thermal ink sheet 55, is suppressed and heated by the transfer roller 59 and the thermal head 50, and after the ink is transferred to the copy paper 12 until it reaches the edge 62, Copy paper 12
and the thermal ink sheet 55 are fed in close contact with each other for a certain period of time,
Thereafter, the thermal ink sheet 55 suddenly changes its direction downward at the edge 62, and the copy paper 12 continues to move straight. The angle of the edge 62 of the blade 61 is made smaller than 90@, so that the downward direction change toward the thermal ink sheet 55 is rapid.

The thermal ink sheet 55 is then wound around the winding shaft 54 at an angle of 0 with respect to the feeding direction.

If the angle 0 is 30@ or more, it will work on separating the copy paper 12, but it is preferably 60' to 90''.

It should be noted that if the length is 90'' or more, the separation effect will be better, but the arrangement of the thermal head 50 will change.

The thermal head 50 transfers the ink to the copy paper 12.
The ink transferred to the copy paper 12 is heated by the heat-sensitive ink sheet 12 and separated after a certain period of time has passed, and the ink transferred to the copy paper 12 cools down and is sufficiently adsorbed to the copy paper surface before being peeled off. Never take sides,
This results in good transfer.

Furthermore, the position of the edge 62 where the thermal ink sheet 55 and the copy paper 12 separate is in the tangential direction of the transfer roller 59, and while the copy paper 12 tends to move straight due to its rigidity, the thermal ink sheet 55 haetsuji 6
As a result of the sudden direction change in part 2, the copy paper 12
and the heat-sensitive ink sheet 55 are well separated. The heat-sensitive ink sheet supply shaft 53 and take-up shaft 54 are held in a casing 70, as shown in FIGS. 4 and 5.

The cartridge 71 to the ink sea 1 is transferred to the casing 70.
Supply shaft 532, winding shaft 54, weight shaft 56. The ink sheet cartridge 71 consists of a heat-sensitive ink sheet 55 and is used for copying.

It is used by being loaded onto the thermal head 50 from above. The ink sheet cartridge 710 casing 70 is
The open lower 2 has a lower surface into which the thermal head 50 can be inserted, and the heating element end surface 5 of the thermal head 50 has an upper surface.
An open lower lower 3 is provided so that the upper surface of the lower part 1 can protrude slightly. Felt is used as a bearing for the supply shaft 53, and this felt is fixed to the casing 70, and the frictional resistance generated when the supply shaft 53 rotates causes a pack when the thermal ink sheet 55 is wound onto the winding shaft 54. It works to give tension. Similarly, the weight shaft 56 also serves to absorb 1-lux fluctuations when the thermal ink sheet 55 is wound up, and also serves to provide pack tension.

The upper surfaces 83 and 84 of the casing 70 of the ink sheet cartridge 71 also serve as guide surfaces for the copy paper 12, as shown in FIG. The upper surface 83 on the entrance side is set at such a height that when the copy paper 12 is inserted, its leading edge is just guided into the nip formed by the transfer roller 59 and the heating element end surface 51 of the thermal head 50. The upper surface 84 on the exit side is formed by the edge 62 of the blade 61 after the ink is transferred.
When the thermal ink sheet 55 is separated and the copy paper 12 continues straight, a guide surface is formed to prevent the leading edge of the copy paper from falling down due to being pulled by the thermal ink sheet 55. The upper surface 84 guides the leading edge of the copy paper 12 and guides it to the copy paper eject 114. In this case, the previous copy paper is pushed by the leading edge of the previous copy paper, and is provided so that it falls into this step 85 and is held there. The winding shaft 54 of the thermal ink sheet and the transfer roller 59 are driven by the same pulse motor (not shown). The driving force of the pulse motor is transmitted to the transfer roller 59 via a gear train for deceleration, whereas the driving force to the winding shaft 54 is transmitted by a slip mechanism made of felt and a spring provided on the way. The thermal ink sheet 5 is wound around the winding shaft 54.
Even if the thickness of the transfer roller 59 changes and the diameter increases, the transfer roller 59 is always
A certain amount of the heat-sensitive ink sheet 55 sent at a circumferential speed is reliably wound up.

When the same number of pulses are applied to the pulse motor for driving the transfer roller 59 and the pulse motor 42 for driving the image sensor unit 30, the transfer amount of the copy paper 12 sent by the transfer roller 59 and the image sensor unit 3
The reduction ratio is set so that the amount of movement of 0 is equal.

Black is usually used for general copying.
In this embodiment as well, the heat-sensitive ink sheet 55 is coated with black ink, but the color is not limited to black.
A variety of thermal ink sheets can be used, such as red, blue, green, yellow, cyan, magenta, brown, gold, silver, etc. To replace the heat-sensitive ink sheet 55, the roller frame 58 is opened upward and the ink sheet cartridge 71 is installed and removed (FIG. 5).

Next, the procedure for actually copying according to this embodiment will be explained. First, after confirming that the ink sheet cartridge 71 is correctly set, the power switch 24 is turned on. The original platen cover 4 is opened and the original 3 to be copied is set face down on the original platen glass 2. Insert the copy paper 12 from the copy paper insertion slot 11. Adjust the copy paper guide 22 according to the width of the copy paper 12. When the copy paper 12 is inserted into the copy paper insertion slot 11 and the leading edge of the copy paper 12 reaches the nip between the transfer roller 59 and the thermal ink sheet 55 covering the heating element end surface 51 of the thermal head 50, the paper sensor 75
is turned on and the copy is enabled.

If you press the copy start button 23 in this state.

The pulse motor 42 and the pulse motor for driving the transfer roller 59 start rotating, the image sensor unit 30 starts scanning the document 3, and the transfer roller 59 starts rotating.
When the copy paper 12 is fed, the heating element of the thermal head 50 is heated according to the image on the original document 3, and melted ink is transferred to the copy paper 12 according to the image on the thermal ink sheet 55. , the copy paper guide 2z is adjusted to match the width of the copy paper 12.
Next, this adjustment mechanism will be explained.

As the copy paper guide 22 slides, the movement of the copy paper guide 22 is transmitted to the slide volume via a speed reduction mechanism including a rack and gears.

The resistance value of this slide volume is electrically detected and
In accordance with the value and the dimensions of the copy paper guide 220, a non-printing portion 81 of about 5111 on both ends in the width direction is created. Although it is possible to continuously change the print width according to the value of the slide volume, in this embodiment, the generally used paper size A4. B5. A5.
The width is changed stepwise to B6 or the like. however,
It is not limited to this.

Corresponding to the paper width set by the leading edge of the copy paper 12 and the copy paper guide 22, as shown in FIG. 7, there are areas 80 and 81 where no printing is performed, each having a length of about 5 m. Since printing is stopped when the trailing edge of the copy paper 12 passes the paper sensor 75, there is also a portion 82 at the trailing edge of the copy paper 12 where no printing is done by approximately 5 mm.

The non-printing portion 80 at the leading edge of the copy paper 12 has a great effect in ensuring that the copy paper 12 and the thermal ink sheet 55 are separated when they begin to separate at the edge 62. The non-printed areas 81 on both sides of the copy paper 12 are
is wider than the copy paper 12, the copy paper 12
This prevents unnecessary ink from being transferred to the transfer roller 59 due to heat being applied to the thermal head 50 up to the portion where there is no .

When the image sensor unit 30 reaches the end point switch 44, it begins to return. However, the transfer roller 59 continues to rotate as long as the paper sensor 75 detects the presence of paper. Therefore, the copy paper is extremely long,
Even after the image sensor unit 30 finishes scanning, the copy paper 12 continues to be fed, so there is no chance of a single paper jam.

Also, when copy paper that is short in length arrives, the paper sensor 75 detects the end of the paper, and after a while the transfer roller 5
Since the rotation of 9 is stopped, there is no need to use too much extra heat-sensitive ink sheet.

The image sensor unit 30 returns to the same starting position as before the start of scanning and stops.

In this embodiment, when the copy paper is set in the copy paper insertion slot 11 again during the return operation until the image sensor unit 30 returns to the start position, the image sensor unit 30 automatically returns to the start position and the next copy is automatically inserted. This is useful when making multiple copies in succession.

(Effect of the invention) If the original is larger than the copy paper, and if the part where there is no copy paper is printed, ink will be transferred to the roller surface in the part where there is no copy paper, which is clear from the explanation above 5. According to the present invention, a copy paper guide that can be adjusted according to the size of the copy paper is provided in the copy paper insertion slot of a thermal transfer type printing unit using a thermal head and a thermal ink sheet, and the copy paper guide is Since the configuration is such that the sliding position of the guide is electrically detected to control the printing range of the thermal head, in the embodiment of the present invention, the size of the copy paper is detected and the printing range outside the width of the copy paper is controlled. It has the effect of preventing printing and preventing dirt on the roller surface.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a thermal transfer copying apparatus according to an embodiment of the present invention, and FIG. 2 is a sectional view of an image sensor unit of the present invention.
FIG. 3 is a perspective view of the image sensor unit of the present invention, FIG. 4 is a cross-sectional view of the main part of the print section of the present invention, and FIG. A sectional view of the main parts showing where the
FIG. 6 is a cross-sectional view showing details of the thermal head of the printing section of the present invention, and FIG. 7 is a plan view of a copy sheet for explaining the present invention in detail. 1...Main body, 2...Original table glass, 3...
JJ draft, 10...Print section, 11...Copy paper insertion slot, 12...Copy paper, 14...
Copy paper ejection n-22...Copy paper guide, 30
...Image sensor unit, 33...Sensor body, 34...LED array, 35...Light convergence fiber lens, 36...Image sensor, 37...
... Roller, 38 ... Spring, 50 ... Thermal head, 53 ... Supply shaft, 54 ... Winding shaft,
55... Thermal ink sheet, 56... Weight shaft, 59... Transfer roller, 61... Blade,
71... Ink sheet cartridge, 72, 73...
・Opening, 83.84...Top surface. Figure 1 1...Main salary 2...Manuscript/Umata 3
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Ipa start kun 24...! 2... Manuscript 8 Power/Las 34... LED array 13... Original #l 35... Light ρ anti-reactive file lC-lens 030... 4 image 7 Brake unit 36...4 image, Seven armature 31...force axis 37...roller 32...sensor base 3
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... Kei Tori Scroll 55゛ 'If4 Kazu Ink Sheet
56・B also has a shaft 57・Support A
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Tsukasa... Cage 7 de 75 Tile, tump Fig. 5 1 14...In''-FF] General Fog Biaoguchi 15...
Power: 4-dore group 50...Thermal refill head 51
・Heat sales rod 53... Carrying axis Nu゛°Dust pan 5 axis 55°° Open'' sheet 56
...Otou axis 57... Good book,
Da1゛υ-ra frame 59... Tsutomu 50-ra
7o...Casing 171 ・Include cart socket 72...Open υ73...vJ
υ Fig. 6 50...Buch Rehehud 51・°-Heating heat rod surface 5
2...4W'3 ft 5
5... Fear of Heat 4 Ink Sheet 59... Chapter! Tiger
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Upper 1584...Top surface

Claims (1)

[Claims] A thermal transfer printing means using a thermal head and a thermal ink sheet is provided, and a copy paper guide that can be adjusted according to the size of the copy paper is installed in the copy paper insertion slot, and the sliding position of this copy paper guide is detected electrically. A thermal transfer copying apparatus, characterized in that the printing range of the thermal head is controlled by