JP2517533Y2 - Image forming device - Google Patents

Description

[Detailed Description of the Invention] "Industrial field of application" The present invention relates to an image forming apparatus for copying and recording using roll paper, and in particular, using two roll paper supply mechanisms to selectively select roll paper. The present invention relates to an image forming apparatus which supplies a cutter to obtain a cut sheet.

“Prior Art” Conventionally, in an automatic paper feeding device using this type of roll paper, the roll paper holding structure is such that a rotary shaft 2 is passed through a roll paper 1 as shown in FIG. Is supported by the bearing member 3 provided on the main body.

By the way, the paper 5 of the roll paper 1 is fed out by the paper feed roller 6 as shown in FIG. 10, and at that time, the slack of the paper 5 is prevented and the skew (diagonal feed)
It is necessary to give so-called back tension to the paper 5 in order to prevent the above and to straighten the cut line by the cutter mechanism (not shown). Therefore, conventionally, as shown in FIG. 9, a friction plate 4 is provided on the rotary shaft 2 so that a constant frictional force is applied to the rotary shaft 2 to provide a constant back tension. .

[Problems to be Solved by the Invention] When a conventional image forming apparatus is provided with two types of roll paper, two types of roll paper having the holding structure as described above are arranged in the apparatus main body to set the roll paper. When performing replacement or replacement, the door of the main body of the apparatus is opened and the work is performed. A cutter for selectively cutting these roll papers is also provided in the main body of the device, and it is possible to set or replace the desired one of the two types of roll paper in a narrow space inside the device. It was tough. In addition, if the device is designed so that these two types of roll paper can be taken out from the front surface of the main body of the device, it is necessary to secure a space necessary for attaching and detaching the roll paper. there were.

Therefore, the purpose of the present invention is to use two types of roll paper,
Moreover, it is an object of the present invention to provide an image forming apparatus in which the apparatus main body can be designed compactly.

"Means for Solving the Problem" In the present invention, (a) an apparatus main body having a built-in recording unit,
(B) A paper feed unit main body which is arranged below the recording unit of the apparatus main body and can be drawn out from the front side to the front side so that the upper part and the front side can be freely opened. A cutter for cutting the roll paper when the roll paper is fed in a state that the paper feed unit main body is accommodated in the main body of the apparatus and is fed to the recording unit, and (d)
In the sheet feeding unit main body, it is detachably set at a position substantially below the cutter from the front side of the apparatus main body through a substantially horizontal path, and at a predetermined time point, the roll paper is unwound from this and supplied to the cutter. (E) In the state where the paper feed unit main body is pulled out to a position substantially adjacent to the cutter within the paper feed unit main body (e), the paper is set detachably from above through a substantially vertical path. The image forming apparatus is provided with a second roll paper supply mechanism that supplies the roll paper from the roll paper supply mechanism to the cutter at a predetermined time when the roll paper supply mechanism does not supply the roll paper.

That is, in the present invention, the first and second roll paper supply mechanisms for supplying two systems of roll paper and the cutter for cutting the roll paper are arranged in the paper feed unit main body, and can be drawn out from the main body of the apparatus. To The upper and front surfaces of the paper feed unit main body can be opened so that the first roll paper supply mechanism can be set from the front surface, that is, the front side of the apparatus main body, and the second roll paper supply mechanism. With regard to the above, the space next to the cutter can be used to set the sheet feeding unit body from above with the sheet feeding unit body pulled out. Since the roll paper supply mechanisms of the two systems are set in different directions in this way, the components of these paper feed systems including the cutter can be efficiently arranged, and the image forming apparatus itself can be made compact. can do.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 3 shows an overall structure of an image forming apparatus according to an embodiment of the present invention. A console panel 12 having operation buttons and a display unit and a toner supply door 13 are provided on the upper surface of a main body 11. Has been. On the front surface of the main body 11, an automatic paper feeder door 14, an automatic paper feeder lock lever 15,
A door 16 that opens when a paper jam occurs, a power switch 17, a paper cutting button 18, and a manual paper feed table 19 are provided. FIG. 4 shows a state in which the automatic paper feeder door 14 is opened and the automatic paper feeder 20 described later is pulled out. The automatic paper feeder 20 includes, for example, two roll papers 21 and 22 as paper supply sources.

FIG. 5 schematically shows the flow of the paper 24 fed from the automatic paper feeder 20. The paper 24 taken out from one of the roll papers 21 and 22 by the paper feed roller 23 is
After being cut to a predetermined length by the cutting mechanism described later,
The toner image is conveyed to the transfer position A of the photosensitive drum 25, and at this transfer position A, the toner image formed on the drum surface by the image forming unit 26 and developed by the developing unit 27 is transferred. The paper 24 onto which the toner image has been transferred is ejected to the tray 29 after the toner image is fixed in the fixing unit 28.

FIG. 1 shows the structure of the holding portion of the roll paper 21. Flange portions 30 and 31 are fixed to both ends of the core of the roll paper 21 by lock levers 32. This roll paper 21
Is mounted on, for example, two shaft members (shafts) 33 and 34, and is in rolling contact with the flange portions 30 and 31. One shaft member 33 is rotatably supported by a sliding bearing member 35 as a rotation control means while receiving a constant frictional force. As the slide bearing member 35, a member formed of a metal such as copper or a plastic material, specifically, for example, a sintered bearing is used. The other shaft member 34 is rotatably supported by a rolling bearing member (ball bearing) 36. Since the roll paper 22 side has the same structure as the roll paper 21, its description is omitted.

FIG. 6 shows a schematic configuration of a cutting mechanism for the paper 25 fed from the roll paper 21. This cutting mechanism
It is composed of a rotary blade 40 and a fixed blade 41, and these are arranged so as to incline to the right with respect to the conveying direction of the paper 24 when viewed from the top surface. Further, these are arranged so as to be inclined upward to the right with respect to the surface of the paper 24 when viewed from the side. Rotary blade 40
CPU via the clutch 42 and an output port not shown
A (central processing unit) 43 is connected, and a motor 44 for driving the feeding roller 23 is electrically connected to the CPU 43 via an output port (not shown). When the paper cutting button 18 is turned on by the operator's operation, the CPU 43 sends a control signal to the clutch 42 and the motor 44. As a result, the sheet 24 is conveyed at a predetermined speed and the clutch 42 is actuated. As a result, the rotary blade 40 rotates about the shaft 45 counterclockwise in the drawing as shown in an enlarged view in FIG.
The paper 24 is moved to the sixth position by the blade edge 40a and the blade edge 41b of the fixed blade 41.
Cut from left to right in the figure. As a result, a straight cut line 47 is formed at right angles to the carrying direction, as shown by the broken line in FIG.

FIG. 8 shows the arrangement of the automatic paper feeder 20. The automatic paper feeder 20 can be pulled out from the main body 11 in a unit form. On the front side of this unit body 50, the automatic paper feeder door 14 can be freely opened and closed.
One roll paper 21 from 14 is mounted inside the unit main body 50. The other roll paper 22 is designed to be loaded from the upper opening of the unit main body 50. In the drawing, the roll paper 22 is disposed diagonally above and to the right of the roll paper 21, and the roll papers 21, 22 and the cutting mechanism portion composed of the rotary blade 40 and the fixed blade 41 form a substantially triangular shape. With this arrangement, the automatic paper feeder 20
The height can be reduced, and the entire structure can be made compact. Further, since the roll papers 21 and 22 are mounted from different directions, they can be taken in and out individually, and the roll papers 21 and 22 can be easily replaced.

Further, a detection sensor 51 is provided so as to face the lower surfaces of the flanges 30 and 31 of the roll papers 21 and 22 mounted in FIG. The paper 24 of the roll papers 21 and 22 has a rear end portion fixed to the core portion with tape or the like,
When the number of sheets of paper 24 becomes small, the roll papers 21 and 22 can be lifted upward by the conveying force of the paper 24.
The sensor 21 turns off when the roll papers 21 and 22 are lifted, and automatically detects that the paper 24 has run out.
By arranging a plurality of these sensors 51 in the horizontal direction corresponding to the sizes of the roll papers 21 and 22, the size of the mounted roll papers 21 and 22 can be automatically detected.

Further, detection sensors (not shown) are arranged on the upstream side and the downstream side of the paper feed roller 23, respectively. Roll paper 21, 22
Is mounted and the leading edge of the paper 24 is positioned between the two paper feed rollers 23, an upstream sensor detects this, and the paper feed roller 23 is rotationally driven by a signal from this sensor, and the paper 24 is automatically fed. Pull out to. Further, when the downstream sensor detects the leading edge of the paper 24, the rotation of the paper feed roller 23 is stopped because the nip of the paper 24 is completed.

In such a configuration, the automatic paper feeder 20 of the present embodiment
In FIG. 8, the roll papers 21 and 22 are mounted from the front and the top of the unit main body 50, respectively, as shown in FIG. When the leading ends of the papers 24 of the roll papers 21 and 22 are positioned between the paper feed rollers 23, the paper feed rollers 23
23 is driven and the paper 24 is automatically nipped, whereby the paper can be fed. In this state, when the operator turns on the paper cutting button 18, the clutch 42 and the motor 44 are actuated, whereby the paper 24 is conveyed at a predetermined speed, and the rotary blade 40 and the fixed blade 41 have a predetermined length. Be cut into.

On the other hand, in the holding portion of the roll papers 21 and 22, when the paper 24 of the roll paper 21 is taken out by the paper feed roller 23, as shown in the case of the roll paper 21 in FIG. At clockwise. And this flange part
With the rotation of 30 and 31, the two shaft members 33 and 34 rotate counterclockwise, respectively. At this time, since the one shaft member 33 is supported by the slide bearing member 35, a frictional force corresponding to the weight of the roll paper 21 is added by the slide bearing member 35, and the roll paper 21 is rotated by that amount. Limited. That is, when there are many sheets of paper 24 or when the size of the sheets of paper is large and the roll of paper 21 is heavy, the frictional force with respect to the shaft member 33 increases, and the rotation of the roll of paper 21 is restricted accordingly, and as a result And big back tension is added. On the other hand, when the roll paper 21 becomes light when the paper 24 is small or the paper size is small, the frictional force on the shaft member 33 becomes small and the rotation of the roll paper 21 becomes smoother by that amount. The tension becomes smaller.
Therefore, an appropriate amount of back tension is applied to the paper 24 according to the change in the weight of the roll paper 21, and the paper 24 is smoothly fed.

Further, since the inertial force of the roll paper 21 is larger as the paper 24 is heavier, the time until the rotation of the paper 24 is stopped is almost constant regardless of whether the paper 24 is large or small. That is, the amount of back tension applied to the paper 24 is
The rotation of the paper 24 can always be minimized to stop the rotation of the paper 24 within a fixed time, and therefore, the back tension of the paper 24 does not exceed the necessary value.

Further, the magnitude of the braking torque with respect to the rotation of the roll paper is the friction plate 4 as shown in FIG.
When the frictional force between and is f, it is expressed by T ₁ = f · r (f is the radius of the rotating shaft 2). On the other hand, in the case of this embodiment, if the frictional force between the shaft member 33 and the bearing member 35 is F, then T ₂ = F · R (R is the radius of the flange portions 30 and 31). Here, since R> r, in order to obtain the same amount of braking torque, that is, the same amount of back tension, F is smaller than f, that is, the conventional friction plate is used as the sliding bearing member 35. A material having a smaller friction coefficient can be used.

Although the present invention has been described with reference to the embodiments, the present invention is not limited to this, and various modifications can be made without departing from the scope of the invention. For example, in the above embodiment, one of the bearing members is the sliding bearing member 35 as the rotation control means, and the frictional force between the sliding bearing member 35 and the shaft member 33 controls the rotation of the roll paper 21. ,
For example, the two bearing members 35 and 36 may both be rolling bearing members, and rotation control means for controlling the rotation of the shaft member 33 may be provided. Also,
It goes without saying that the number of shaft members that support the roll papers 21 and 22 is not limited to two.

[Advantage of Invention] As described above, according to the present invention, since the main body of the paper feeding unit is arranged so as to be freely drawn out from the main body of the apparatus, it is possible not only to easily perform paper feeding with the main body of the paper feeding unit pulled out. Since the cutter is arranged on the main body of the paper feeding unit, maintenance of the cutter and paper jam processing in the vicinity of the cutter can be easily performed. In addition, the first roll paper supply mechanism is attached and detached from the front side of the apparatus main body,
Since the roll paper supply mechanism of No. 1 is attached to and detached from the upper part of the main body of the apparatus, these roll paper supply mechanism and cutter can be efficiently arranged in the paper feed unit main body, and the height of the image forming apparatus can be reduced. This not only contributes to downsizing, but also has the effect of facilitating the replacement of individual roll papers.

[Brief description of drawings]

FIGS. 1 to 8 show an embodiment of the present invention. FIG. 1 is a perspective view showing the structure of a roll paper holder, and FIG. 2 is a view for explaining the operation of the holder. 3, FIG. 3 is a perspective view showing the external appearance of the image forming apparatus, FIG. 4 is a perspective view showing a state in which the automatic sheet feeding device is pulled out, and FIG. 5 is a schematic configuration for explaining the operation of the entire image forming apparatus. 6 and 6 are configuration diagrams of the cutting mechanism, FIG. 7 is a configuration diagram for explaining the operation at the time of cutting, FIG. 8 is a partial cross-sectional view for explaining the arrangement configuration of the automatic sheet feeder, and FIG. FIG. 10 is a front view showing the configuration of a conventional roll paper holding unit, and FIG. 10 is a view for explaining the holding operation. 11 …… (Image forming device) Main unit 14 …… Automatic paper feeder door 20 …… Automatic paper feeder 21, 22 …… Roll paper, 23 …… Feeding roller 25 …… Photosensitive drum 26 …… Image formation Part 27 …… Developing part 40 …… Rotating blade 41 …… Fixed blade 50 …… Unit body (paper feed unit body)

Claims (2)

(57) [Scope of utility model registration request] 1. An apparatus main body having a built-in recording unit, and a paper feeding unit main body which is arranged below the recording unit of the apparatus main body and which can be pulled out from the front side to the front side and whose upper and front sides can be freely opened. And a cutter for cutting the roll paper when the roll paper is fed in a state where the paper feed unit main body is housed in the apparatus main body and feeding the roll paper to the recording unit. In the paper feeding unit main body, it is detachably set to a position substantially below the cutter from the front side of the apparatus main body through a substantially horizontal path, and at a predetermined time, roll paper is unwound from this and supplied to the cutter. And a first roll paper supply mechanism that is attached to and detached from a top of the paper feed unit main body through a substantially vertical path in a state where the paper feed unit main body is pulled out to a position substantially adjacent to the cutter. A second roll paper supply mechanism that is freely set and that supplies the roll paper to the cutter at a predetermined time when the roll paper is not delivered from the first roll paper supply mechanism. Image forming apparatus. 2. The cutter is arranged on the front upper side of the paper feeding unit main body, and the second roll paper supply mechanism is opened to the back side of the cutter with the paper feeding unit main body being pulled out. The image forming apparatus according to claim 1, wherein the image forming apparatus is set in a predetermined space.