JPH04257471A - Printer - Google Patents

Abstract

PURPOSE:To achieve miniaturization of a printer by a method wherein paper printed with an forming part provided onto a paper storing part is discharged into an upper space the paper storing part. CONSTITUTION:An opposed paper conveying path 32 is provided by having a specific gap to an upper surface of a paper storing part 1, and a paper feed roller 23 arranged freely rotatably between an end part of upmost layer paper 4 in the paper storing part 1 and an end part of the paper conveyign path 32 and an image forming part 31 are arranged by using a space above the end part of the paper storing part 1. Besides by discharging the paper 4 from the image forming part 31 by using the space above the paper storing part 1, both installing space and total height dimension of the printer are effectively reduced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing device.

0002

2. Description of the Related Art Conventionally, as shown in FIG. 6, paper in a paper feed cassette 101 provided at the bottom of a housing 100 is pulled out while being reversed by a paper feed roller 102.
3, and convey this paper in the direction of the arrow to the housing 1.
In the process of ejecting the paper to the paper ejection tray 113 formed on the upper surface of the 00, the developed image formed on the photoreceptor 104 is transferred to the paper, and the transferred image transferred to the paper is transferred to the fixing roller 1.
There is a printing device which fixes at 05. Here, the electrostatic latent image is formed on the photoreceptor 104 by applying charges to the photoreceptor 104 from the charger 106.
This is carried out by charging the outer circumferential surface of , and scanning this charged portion with an optical signal corresponding to an image signal from the exposure unit 107 . This electrostatic latent image is developed by a developing device 108, and this developed image is transferred onto paper by a transfer charger 109. Further, the photoreceptor 104 is connected to a cleaning unit 110.
Cleaned by.

Furthermore, as shown in FIG. 7, the paper in the paper feed cassette 112 attached to the side surface of the housing 111 is transferred to the photoreceptor 10 via the paper feed roller 102 and the conveyance roller 103.
There is a printing device that transfers the developed image on the photoreceptor 104 to the paper during the process of supplying the paper to the photoreceptor 104 and subsequently discharging the paper to a paper ejection receiver 113 formed on the top surface of the casing 111. Note that the principle of forming and fixing an image on the photoreceptor 104 is the same as that shown in FIG. 6, so the same parts are denoted by the same reference numerals and explanations will be omitted.

0004

[Problems to be Solved by the Invention] In the case shown in FIG. 6, the height of the casing 100 is increased in order to arrange the photoreceptor 104 at the upper part of the paper feed cassette 101 with an interval for reversing the paper. , and also the paper feed roller 102 and the photoreceptor 104.
Since a conveying roller 103 that conveys the paper pulled out by the paper feed roller 102 to the photoreceptor 104 is disposed between the housing 100 and the housing 100, the length of the housing 100 cannot be shortened. In the case shown in FIG. 7, the housing 1 is
It is possible to limit the height of paper cassette 1.
12 protrudes from the side surface of the housing 111, resulting in a problem that the installation area becomes large.

[0005]

[Means for Solving the Problems] The invention as claimed in claim 1 provides a paper storage unit in which a large number of sheets of paper are stored in a stacked state, and a paper storage unit that faces the upper surface of the paper storage unit at a predetermined distance. a conveyance path; a paper feed roller rotatably disposed between an end of the top layer of paper in the paper storage section and an end of the paper conveyance path; and an image disposed above the paper storage section. The paper forming section is configured to include a paper forming section, and a paper ejection receiver that is continuous with the paper ejection side of the paper transport path and is provided at the upper part of the paper storage section.

According to a second aspect of the invention, in the first aspect, a paper support is provided on the paper discharge side of the image forming section to support the trailing edge of the paper.

[0007] The invention according to claim 3 is characterized in that, in claim 1 or 2, an image forming unit that forms an image by electrophotography and has a photoreceptor disposed below the paper transport path is placed above the paper storage unit. and the outer diameter of the photoreceptor is set to be smaller than the outer diameter of the paper feed roller, and the leading end of the uppermost layer of paper in the paper storage section and the end of the paper transport path on the paper feed roller side. The height between them was made approximately equal to the diameter of the paper feed roller.

[0008]

[Operation] In the invention as claimed in claim 1, the paper in the paper storage section is reversed to the paper transport path by the paper feed roller, is printed by the image forming section during the process of being transported along this paper transport path, and then is ejected. Although the paper is ejected to the receiver, since the paper storage section and the paper ejection receiver are arranged using the space above the paper storage section, the installation space and overall height of the printing device are effectively reduced.

In the second aspect of the invention, since the trailing edge of the ejected paper is supported by the paper support, a space as a partition is formed between the ejected paper and the paper in the paper storage section. Therefore, the upper surface of the paper in the paper storage section can be used as a paper ejection receiver, thereby simplifying the structure of the paper ejection receiver.

In the third aspect of the invention, the height on the paper feed roller side from the top layer of paper in the paper storage section to the paper transport path is limited to about the diameter of the paper feed roller, and the height below the paper transport path is limited to the diameter of the paper feed roller. Since the photoreceptor is placed in the paper storage area and the paper transport area, the image forming section can be installed at a lower position.Moreover, the photoreceptor is formed with an outer diameter smaller than the outer diameter of the paper feed roller. It is possible to reduce the distance between the image forming section and the image forming section, and it is also possible to easily arrange each process unit for charging, development, transfer, etc. of the image forming section in a small space.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 to 5. 1 and 2 are longitudinal sectional front views. In the figure,
1 is a paper storage section. The paper storage unit 1 is held movably in the width direction of the paper 4 by a flat paper feed body 2 that is slightly larger than A4 size paper 4 and a protrusion 3 formed at the bottom of the paper feed body 2. It consists of a mounting plate 5 and a pressing plate 6 which is held on the paper feed main body 2 so as to be able to rise and fall freely. Guides 7 for supporting both side edges of the paper 4 are formed on both sides of the mounting plate 5. Further, although the pressing plate 6 holds the sheets 4 in a stacked state and is biased by a spring 8 in a direction away from the mounting plate 5, the guide 7 may be provided with a stopper 9 that contacts the top layer of sheets 4. This limits excessive upward movement. Further, an electrical equipment compartment 10 is formed at the bottom of the paper feed main body 2, and the electrical equipment compartment 10 is provided with an electrical equipment case 11 and a circuit board 12 connected to the electrical parts housed in the electrical equipment case 11. It is being Electrical equipment room 1
A plurality of legs 14 are fixed to a base plate 13 that closes the bottom of the desk. Further, a lid 15 is attached to the upper surface of the paper feed main body 2 so as to be openable and closable.

[0012] A printing unit 16 is provided above the paper storage section 1. This printing unit 1
Reference numeral 6 denotes a case 18 which is rotatably held on both sides of the paper feed main body 2 by a fulcrum shaft 17, a support 19 fixed to this case 18, and a support body 19 which is rotatably held by the case 18 by a fulcrum shaft 20. It has a cover 21. A developer container 22 for storing developer is integrally formed in the case 18. The case 18 also includes a paper feed roller 23, a photoreceptor 24 whose outer diameter is approximately half the outer diameter of the paper feed roller 23, a developing roller 25, and a developer layer with a thickness A regulating roller 26 and a fixing roller 27
are rotatably held, and a motor (not shown) for driving these rotating bodies is fixed. Furthermore, a paper support 18a that supports the rear end of the paper 4 is formed at the end of the case 18 on the paper discharge side.
A paper ejection receiver 15a is formed on the upper surface of the lid 15 that is continuous with the lid 8a.

The support 19 includes a charger 28 that applies a voltage to the photoreceptor 24 to charge the photoreceptor 24, and a charger 28 that irradiates the charged portion of the photoreceptor 24 with a light signal corresponding to an image signal. An exposure section 29 that forms an electrostatic latent image and a photoreceptor 24
An auxiliary brush 30 that evens out the developer remaining on the outer peripheral surface of the
and a static eliminator 30a that neutralizes the charge on the photoreceptor 24. The exposure section 29 is formed by arranging a large number of edge light emitting elements in a line. The above-mentioned photoreceptor 24 and the developing roller 2 in the developer container 22 are connected to each other.
5 and regulation roller 26, fixing roller 27, press roller 41, charger 28, exposure section 29, auxiliary brush 30, static eliminator 30a, and transfer roller 39, forming image forming section 31. .

A paper conveyance path 32 is formed between the case 18 and the cover 21, and the paper conveyance path 32 and the extension surface (paper feed path) of the uppermost layer of paper 4 on the press plate 6 are similar to each other. , a plurality of ribs 34 connected by a reversing path 33 formed by a part of the outer circumferential surface of the paper feed roller 23, and for promoting the guiding action of the paper 4 through this reversing path 33.
is formed in the case 18. Further, a manual paper feed port 35 is formed at the end of the paper transport path 32 on the paper feed roller 23 side.

Furthermore, a paper guide surface 37 is formed on the toner cartridge 36 mounted in the developer container 22, and a paper guide plate 38 facing the paper guide surface 37 is held by the cover 21. The transfer roller 39 is rotatably held in the cover 21 in contact with the photoreceptor 24 . The paper guide plate 38 is formed of a leaf spring, and a pinch roller 40 and the press roller 41 are rotatably held at both ends thereof while being urged toward the case 18 side. As a result, the pinch roller 40 is brought into pressure contact with the paper feed roller 23, and the press roller 41 is brought into pressure contact with the fixing roller 27. Further, near the tip of the press plate 6 in the paper storage section 1, a lever 43 having a friction member 42 at the tip is biased clockwise by a spring 44 and is held rotatably about a support shaft 45. has been done. Thereby, the friction member 42 is brought into elastic contact with the outer peripheral surface of the paper feed roller 23. Further, a connector 46 for inputting power supply voltage, image signals, etc. is fixed to the case 18 of the printing unit 16, and a connector 47 connected to the circuit board 12 is provided in the paper storage section 1, These connectors 46 and 47 are connected by a cable 48.

Furthermore, the case 18 is provided with a stop lever 49. As shown in FIG. 3, this stop lever 49 is urged clockwise by a spring 50 and is rotatably held by a support shaft 51, and a stop shaft 52 facing the side edge of this stop lever 49 is attached to the case 18. It is erected on the side of the Further, a protrusion 53 is formed at the lower end of the stop lever 49 and comes into contact with the upper surface 2a of the paper feed main body 2. Here, FIG. 3 shows the paper feed main body 2.
2 is a side view showing the relative relationship between the upper surface 2a of the printer and the case 18 of the printing unit 16. FIG. That is, when the case 18 rotates upward about the fulcrum shaft 17, the relative position with respect to the upper surface 2a of the paper feed main body 2 changes. When the relative position of the upper surface 2a to the case 18 is L, the case 18 is located at the lower position and is in contact with the upper surface 2a of the sheet feeding main body 2. In this state, the upper surface 2a and the projection 53 contact each other. The rotational movement of the stop lever 49 is blocked, so that the upper part of the stop lever 49 projects into the manual paper feed port 35. When the relative position of the top surface 2a with respect to the case 18 is H, the case 18 is located at the upper position and is separated from the top surface 2a of the paper feed main body 2. In this state, the stop lever 49 is moved by the spring as shown by the imaginary line. It rotates clockwise due to the biasing force of 50, and its tip retreats below the manual paper feed port 35.

FIG. 4 is a front view showing the support structure of the case 18 of the printing unit 16 with respect to the paper feed main body 2. The fulcrum shaft 17 and the pin 54 are provided on the front and back surfaces of the case 18.
has been erected. Further, on the front and back sides of the paper feed main body 2, an L-shaped groove 55 for holding the fulcrum shaft 17 and a pin 5 are provided.
A notch 56 having an opening on the top surface into which the pin 54 is fitted is formed, and a hook 58 that is rotatably held on the support shaft 57 and latched to the pin 54 is provided. This hook 5
8 is biased in one direction by a spring 59,
Excessive rotational movement is prevented by the pin 60.

FIG. 5 shows the paper feed roller 2 partially in cross section.
FIG. 3 is a side view showing the support structure of No. 3; That is, a drive shaft 61 is provided that is connected to a motor via a spring clutch (not shown). The drive shaft 61 includes a hub 63 that is prevented from rotating by a pin 62, and a hub 63 that is fixed to the drive shaft 61 by a pin 62.
a hub 6 rotatably and slidably fitted in the axial direction of the hub 1;
4 and an elastic roller 65 that is rotatably fitted to one hub 63 and fixedly fitted to the other hub 64. The hub 64 is biased in one direction by a spring 66, and the hub 64 is biased in one direction by a spring 66.
A rotation transmitting portion 67 is formed on the opposing surfaces of the rotation transmitting portions 3 and 64 and is removably engaged with each other through a relationship between a protrusion and a groove. Further, a pair of rings 68 disposed on both sides of the paper feed roller 23 are fixedly fitted onto the drive shaft 61. These rings 68 are set to have an outer diameter smaller than the outer diameter of the paper feed roller 23, but a portion of the outer periphery is provided with a protrusion 6 that protrudes with a radius larger than the radius of the paper feed roller 23.
9 is integrally formed. These protrusions 69 function to press the top layer of paper 4 on the press plate 6 and separate the paper 4 from the paper feed roller 23 when the paper feed roller 23 is stopped. The spacing between the sides is set to match the width of the postcard.

In such a configuration, when printing using the paper 4 in the paper storage section 1, as shown in FIG. Maintain the state in which it is in contact with 2a. In this state, as described above, the tip of the stop lever 49 protrudes upward from the manual paper feed port 35, so that the paper feeding operation from the manual paper feed port 35 is prohibited. Then, when the paper feed roller 23 is driven clockwise, the sheets 4 stacked on the press plate 6 are separated one by one by the friction member 42 and pulled out, and are reversed toward the paper transport path 32 through the reversing path 33. . A photoreceptor 24 is attached to the paper 4 conveyed along this paper conveyance path 32.
The upper developed image is transferred by the transfer roller 39, and the transferred image is fixed by the fixing roller 27. The paper 4 on which the image has been transferred in this manner is discharged onto the upper surface (paper discharge tray 15a) of the lid 15 of the paper storage section 1. Also, since the paper 4 after image formation is ejected onto the top layer of paper 4 in the paper storage section 1, a partition is used between the ejected paper 4 and the paper 4 in the paper storage section 1. A space is formed. Thereby, it is also possible to use the upper surface of the paper 4 in the paper storage section 1 as a paper ejection receiver. Accordingly, the structure of the paper ejection receiver is simplified.

In FIG. 3, the stop lever 49 is biased by a spring 50, and its protrusion 53 presses against the upper surface 2a of the paper feed main body 2, and the reaction force of the pressing force acts as an upward rotational force on the printing unit 16. However, when feeding paper from the paper storage section 1, as shown in FIG. Rotational movements are prevented.

Therefore, in FIG. 4, the spring 5
When the hook 58 is rotated counterclockwise against the biasing force of the spring 50 and removed from the pin 54, the stop lever 49 is rotated clockwise due to the biasing force of the spring 50, as shown by the imaginary line in FIG. Since the projection 53 presses the upper surface 2a of the paper feed main body 2, the reaction force causes the printing unit 16 to rotate upward about the fulcrum shaft 17. As a result, as shown in FIG. 2, a gap s is formed between the left upper surface of the paper feed main body 2 and the left lower surface of the case 18. In this state, the upper end of the stop lever 49 is retracted below the manual paper feed port 35, so that paper can be fed from the manual paper feed port 35.

As described above, the paper 4 in the paper storage section 1 is reversed by the paper feed roller 23 and conveyed to the photoreceptor 24.
Further, the paper inserted from the manual paper feed port 35 is also conveyed to the photoreceptor 24 by the paper feed roller 23, and it becomes possible to convey sheets of different paper feed paths with only one paper feed roller 23. It becomes possible to reduce the installation space of the printing device.

Further, a photoreceptor 2 is placed below the paper conveyance path 32.
4, the mounting position of the image forming section 31 can be lowered, and the photoreceptor 24 is located closer to the paper feed roller 2.
3, the distance between the paper storage section 1 and the paper conveyance path 32 can be reduced, and the distance between the paper storage section 1 and the paper conveyance path 32 can be reduced. Each process unit can be easily arranged within a small space. Moreover, the printing unit 16 can be placed without protruding from the upper surface of the paper feed main body 2 installed on a desk, and the paper 4 after printing can also be ejected onto the lid 15 of the paper feed main body 2. This allows the installation space to be extremely small.

In this embodiment, the outer diameter of the paper feed roller 23 is set to about 20 mm, and the outer diameter of the photoreceptor 24 is set to about 10 mm. As a result, the length of the printing unit 16 in the paper feeding direction is about 70 mm, the height is about 30 mm, and the width corresponds to the width of A4 size paper 4, making it compact enough to be owned by an individual. Further, even if the size of the paper 4 to be used changes, only the width dimension of the image forming section 16 changes somewhat, and the height and length are maintained within fixed dimensions.

Although the above embodiments have been explained using an image forming section that forms images by electrophotography, the present invention is also applicable to those using an image forming section equipped with a line-type thermal head or an inkjet printer head. It is something that will be done.

[0026]

The invention according to claim 1 has the following features: a paper storage section in which a large number of sheets of paper are stored in a stacked state; a paper transport path that faces the upper surface of the paper storage section at a predetermined distance; a paper feed roller rotatably disposed between an end of the uppermost layer of paper in the paper storage section and an end of the paper transport path; an image forming section disposed above the paper storage section; Since the paper ejection tray is connected to the paper ejection side of the paper transport path and is provided at the upper part of the paper storage section, the paper in the paper storage section is reversed to the paper transport path by the paper feed roller, and the paper is transferred to the paper transport path. During the process of being conveyed through the conveyance path, the paper is printed by the image forming section and then ejected to the paper ejection tray.The paper storage section and the paper ejection tray are arranged using the space above the paper storage section. Therefore, the installation space and overall height of the printing device can be significantly reduced.

According to the second aspect of the invention, in the first aspect, a paper support for supporting the rear end of the paper is provided on the paper discharge side of the image forming section, so that the rear end of the discharged paper is supported by the paper support. As a result, a space is formed as a partition between the ejected paper and the paper in the paper storage unit. Therefore, the top surface of the paper in the paper storage unit can be used as a paper ejection tray. This has the effect of simplifying the structure of the paper receiving tray.

[0028] The invention according to claim 3 is characterized in that, in claim 1 or 2, an image forming unit that forms an image by electrophotography and has a photoreceptor disposed below the paper transport path is located above the paper storage unit. and the outer diameter of the photoreceptor is set to be smaller than the outer diameter of the paper feed roller, and the leading end of the uppermost layer of paper in the paper storage section and the end of the paper transport path on the paper feed roller side. Since the height between the sheets is approximately equal to the diameter of the paper feed roller, the height on the paper feed roller side from the top layer of paper in the paper storage section to the paper transport path can be made approximately the diameter of the paper feed roller. In addition, since the photoconductor is placed below the paper transport path, the mounting position of the image forming section can be lowered, and the photoconductor is formed with an outer diameter smaller than the outer diameter of the paper feed roller. Therefore, the distance between the paper storage section and the paper transport path can be reduced, and each process unit for charging, development, transfer, etc. of the image forming section can be easily arranged in a small space. It has the effect of

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a state in which paper is fed from a paper storage unit, according to an embodiment of the present invention.

FIG. 2 is a vertical sectional front view showing a state of paper being fed from the manual paper feed port.

FIG. 3 is a side view showing the opening/closing operation of the manual paper feed slot by the stop lever.

FIG. 4 is a front view showing the support structure of the printing unit with respect to the paper storage section.

FIG. 5 is a longitudinal sectional side view of the paper feed roller.

FIG. 6 is a front view showing the internal structure of a conventional printing device.

FIG. 7 is a front view showing the internal structure of a conventional printing device.

[Explanation of symbols]

1 Paper storage section 4 Paper 15a　Paper output tray 18a Paper support 23 Paper feed roller 24 Photoreceptor 31 Image forming section 32 Paper conveyance path

Claims (3)

[Claims] 1. A paper storage section in which a large number of sheets of paper are stored in a stacked state, a paper transport path facing the upper surface of the paper storage section at a predetermined distance, and a top layer of the paper storage section. a paper feed roller rotatably disposed between an end of the paper and an end of the paper conveyance path, an image forming unit disposed above the paper storage section, and a paper discharge from the paper conveyance path. 1. A printing device comprising: a paper ejection tray that is continuous to the side and provided above the paper storage section. 2. The printing apparatus according to claim 1, further comprising a paper support for supporting a rear end of the paper on the paper discharge side of the image forming section. 3. An image forming section that forms an image by electrophotography, having a photoreceptor placed below the paper conveyance path, is provided above the paper storage section, and the outer diameter of the photoreceptor is set to the paper feed roller. The diameter of the paper feed roller is set to be smaller than the outer diameter of the paper feed roller. 3. The printing device according to claim 1, wherein the printing device is approximately equal to .