JP2001130792A - Machine-glazed-paper holder for large printer, and large printer having it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate setting of machine glazed paper to a machine-glazed- paper holder and to reduce load of an operator following the setting. SOLUTION: The machine-glazed-paper holder 22 is mounted to a sidewall of a paper feed part 2. The machine-glazed-paper holder 22 is provided with a bearing portion 22a for supporting a machine-glazed-paper shaft during paper feed, and a temporarily placing portion 22b on which the machine-glazed-paper shaft is temporarily placed before the machine-glazed-paper shaft is set to the bearing portion 22a. The temporarily placing portion 22b is disposed in the front-side diagonally upward of the bearing portion 22a, and comprises a circular arc recessed part 222. The front end of the recessed part 222 is disposed at a position higher than its rear end. The rear end of the recessed part 222 is disposed at a position higher than the front end of a recessed part 220 structuring the bearing portion 22a, and the space between both ends is formed with a linear portion 223 that declines diagonally backward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an A1 or B1
The present invention relates to a roll paper holder of a large printer capable of printing up to a printing paper of a medium size and a large printer including the roll paper holder of the large printer.

[0002]

2. Description of the Related Art A large-size printer capable of printing up to A1 size or B1 size printing paper is provided with a roll paper holder for mounting roll paper in order to print on roll paper. Section.

[0003] The conventional roll paper holder is provided with only a bearing for supporting a roll paper shaft (spindle) on which the roll paper is mounted at the time of feeding the roll paper. The roll paper shaft was set directly on the machine.

[0004]

However, roll paper handled by such a large-sized printer, especially roll paper of A1 size or B1 size or a similar size, becomes quite heavy, and the roll paper is lifted up. However, setting directly on the bearing of the roll paper holder was a considerable burden.

In particular, since the roll paper rotates around the roll paper shaft and the roll paper is fed to the printing unit from the front side of the roll paper, the bearing unit is particularly required to supply the roll paper. The center of the paper or at the back (or deeper) than the center
It is provided on the side. Therefore, it is difficult to accurately and directly set the roll paper shaft to the bearing part at such a position, and it is not possible to set the roll paper shaft properly and it may be necessary to reset it many times. I was

SUMMARY OF THE INVENTION The present invention has been made in view of such a situation, and an object thereof is to make it easier to set roll paper in a roll paper holder and to reduce the burden on an operator involved in the setting.

[0007]

In order to achieve the above object, a roll paper holder for a large printer according to the first aspect of the present invention is provided in a paper feeding section of the large printer, and a roll paper is attached thereto. A roll paper holder for a large-sized printer, which supports a roll paper shaft during feeding of the roll paper and has a bearing portion formed by a concave portion opened upward, and temporarily supports the roll paper shaft. And a provisional placing section is provided in front of the bearing section.

According to the first aspect of the present invention, since the roll paper holder is provided with a temporary placing portion for temporarily supporting the roll paper shaft in front of the bearing, the roll paper shaft is First, it is set on the temporary placement part in the front, and then on the bearing part behind it.

Here, since the temporary placing portion is disposed in front of the bearing portion, it can be set more easily than when the roll paper shaft is directly set on the bearing portion, and the burden on the operator can be reduced. Further, once the roll paper shaft is placed on the temporary placing portion, the operator can release the roll paper, so that the burden on the operator can be reduced. Furthermore, the setting of the roll paper from the temporary storage section to the bearing section is performed by moving the roll paper from the front to the rear, and this operation is easier than setting the roll paper directly to the bearing section. Thus, the burden on the operator can be reduced.

[0010] When the roll paper is taken out from the roll paper holder, the roll paper can be taken out after the roll paper has been temporarily placed on the temporary holding portion from the bearing portion. Can be reduced.

According to a second aspect of the present invention, in the roll paper holder for a large-sized printer according to the first aspect of the present invention, in the first aspect, the temporary placement portion is formed by a concave portion having a smaller depth than the bearing portion and opening upward. Has been characterized.

[0012] According to the second aspect of the present invention, since the temporary placing portion is formed by a concave portion having a smaller depth than the bearing portion and opening upward, the roll paper shaft can be quickly moved to the bottom of the concave portion. Can be abutted. This gives
Since the operator can quickly release the roll paper shaft, the setting of the roll paper is further facilitated, and the burden on the operator can be reduced.

According to a third aspect of the present invention, there is provided a roll paper holder for a large-sized printer according to the first or second aspect.
The temporary placement portion is formed by a concave portion that opens upward and is larger than the bearing portion.

According to the third aspect of the present invention, since the temporary placing portion is formed by a concave portion which is opened upward and is larger than the bearing portion, positioning of the roll paper shaft on the temporary placing portion is easy. Thus, the roll paper shaft can be quickly set on the temporary placing portion. Thereby, the setting of the roll paper is further facilitated, and the burden on the operator can be reduced.

According to a fourth aspect of the present invention, there is provided a roll paper holder for a large-sized printer according to the second or third aspect of the present invention.
The temporary placement portion is disposed adjacent to and obliquely above the bearing portion, the front end of the temporary placement portion is disposed obliquely above the rear end, and the rear end of the temporary placement portion is , Connected to the front end of the bearing portion.

According to the invention as set forth in claim 4 of the present application, the temporary placing portion is disposed diagonally above and adjacent to the bearing portion, and the front end of the temporary placing portion is disposed obliquely above the rear end,
Since the rear end of the temporary mounting part is connected to the front end of the bearing,
The setting of the roll paper shaft from the temporary placing portion to the bearing portion can be performed by a simple operation of rolling the roll paper shaft from the temporary placing portion to the bearing portion using its own weight (gravity). In addition, since it uses its own weight (gravity), it can be operated with a small force. As a result, the burden on the operator can be reduced.

According to a fifth aspect of the present invention, there is provided a roll paper holder for a large-sized printer according to the fourth aspect, wherein a portion near a rear end of the temporary placing portion is substantially horizontal.

According to the fifth aspect of the present invention, the portion near the rear end of the temporary placing portion is substantially horizontal, and the rear end of the bearing is located behind the rear end as described in the fourth aspect of the present invention. It is connected to the front end of the part. Therefore, the operation of rolling down the roll paper shaft from the temporary placing portion to the bearing portion is further facilitated, and the burden on the operator can be further reduced.

According to a sixth aspect of the present invention, in the roll paper holder for a large-sized printer according to the fifth aspect, the temporary placement portion is formed by an arc-shaped concave portion.

According to the sixth aspect of the present invention, since the temporary placing portion is formed by an arc-shaped concave portion, the operation of rolling down the roll paper shaft from the temporary placing portion to the bearing portion is further facilitated. The burden on the operator can be further reduced.

According to a seventh aspect of the present invention, there is provided a large-sized printer including the roll paper holder of the large-sized printer according to any one of the first to sixth aspects. According to the invention described in claim 7 of the present application, claim 1 of the present application
The same operation and effect as the invention described in any one of the above items 6 to 6 can be obtained.

[0022]

FIG. 1 is a perspective view showing the overall configuration of a large-size printer to which a roll paper holder according to the present invention is applied. The large-sized printer 1 can print up to a printing sheet of about A1 size or B1 size, and includes a paper feeding unit 2, a printing unit 3, and a paper discharging unit 4. A leg (not shown) for supporting the large-size printer 1 at an easy-to-operate height with the operator standing can also be attached to a lower portion of the paper discharge unit 4.

The paper feed unit 2 is formed so as to protrude to the upper rear part of the large printer 1. A roll paper cover 21 is attached to the paper supply unit 2 so as to be openable and closable. A roll paper holder (not shown, detailed later) according to the present invention is mounted inside the roll paper cover 21, and roll paper (not shown) is set in the roll paper holder. A cut sheet (not shown) is set on the upper surface of the front end 21a of the roll paper cover 21. Between the front end of the front end 21a and the upper part of the printing unit 3,
A gap (opening) 25 is formed for the operator to insert his hand when opening and closing the roll paper cover 21. Roll paper or cut sheet paper (hereinafter referred to as "print paper"
That. ) Are sent to the printing unit 3. The detailed configuration and operational effects of the printing unit 2 will be described later.

The printing unit 3 includes a platen, a carriage (not shown) and the like, and an ink cartridge case 32 protrudingly formed on the front surface thereof. Inside the ink cartridge case 32, an ink cartridge (not shown) containing ink is stored.
Is supplied, and ink is supplied to a print head (not shown) attached to the carriage via an ink tube (not shown). The printing paper fed from the paper feeding unit 2 to the printing unit 3 is printed by the print head while being transported in the sub-scanning direction.

On the front surface of the printing unit 3, a front cover 3 is provided.
1 is manually opened and closed. An opening (not shown) is formed inside the front cover 31 so that maintenance (removal of a paper jammed print sheet, cleaning of a platen, and the like) can be performed through the opening. It has become.

The printing paper printed by the printing unit 3 is conveyed to the paper discharging unit 4, and the conveyed printing paper is discharged obliquely downward along the paper discharging slope 41. .

Next, the detailed configuration and operation and effect of the sheet feeding section 2 will be described in detail. FIG. 2 is a front view of the paper feeding unit 2 with the roll paper cover 21 opened, and FIG. 3 is a plan view of the large printer 1 in the same state.

On both side walls 20, 20 of the main body of the paper feeding unit 2,
The two cover side walls 21c, 21c of the roll paper cover 21 and the roll paper holders 22, 22 according to the present invention are attached. The cover side walls 21c, 21c have the same structure except that they are symmetrical. The same applies to the roll paper holders 22,22. Therefore, hereinafter, the right cover side wall 21c and the right roll paper holder 22 will be described, and the description of the left cover side wall 21c and the left roll paper holder 22 will be omitted.

FIGS. 4, 5 and 6 are left side views (partially sectional views) of the right cover side wall 21c and the right roll paper holder 22, and FIG. 4 shows a state in which the roll paper cover 21 is closed. 5 shows a state in which the roll paper cover 21 is being opened and closed, FIG. 6 shows a state in which the roll paper cover 21 is open,
Each is shown. FIG. 7 is a plan view of the roll paper holder 22. FIG. 8 shows a roll paper shaft (spindle) 6 set in the roll paper holder 22 and the roll paper shaft 6.
FIG. 3 is a perspective view showing a roll paper 5 mounted on the paper. FIG.
FIG. 4 is an operation explanatory view of a roll paper shaft 6 set in a roll paper holder 22. FIG. 10 is a left side sectional view showing the sheet feeding unit 2 and a part of the printing unit 3.

Since FIGS. 4 to 6 and 10 are all left side views, the right side in these figures is the front side of the sheet feeding section 2 (large printer 1).

First, the roll paper holder 22 will be described in detail with reference to FIGS. Roll paper holder 22
Has a bearing portion 22a and a temporary placing portion 22b.
The bearing portion 22a is a portion where the roll paper is finally set, and when the roll paper is fed to the printing section 3, supports the shaft end 61 of the roll paper shaft 6 in FIG. The temporary placing portion 22b is configured so that the shaft end 61 of the roll paper shaft 6 is
This is a portion where the shaft end portion 61 is temporarily placed before the roll paper is set or when the roll paper is taken out from the bearing portion 22a, and is provided to reduce the burden on the operator who sets the roll paper. Depth of bearing part 22a and temporary placing part 22b (FIG. 7)
Is set to a length that can stably support the shaft end 61.

The bearing portion 22a is arranged near the center of the side wall 20 (see FIGS. 2 and 3) of the paper feeding section 2 so that the roll paper is rotated stably during paper feeding. The center of the paper shaft 6 is arranged at the position indicated by the symbol A.

The bearing portion 22a has a structure opened upward so that the shaft end portion 61 can be fitted from above, and has an arcuate shape large enough for the shaft end portion 61 to be fitted and turned. And a linear portion 221 that rises linearly upward and supports the shaft end 61 from behind. In order to make the rotation of the roll paper shaft 6 smooth, two rollers 2
20a and 220b and an urging member (spring or the like) 220c for urging the shaft end 61 upward are attached.

The temporary placing portion 22b is disposed adjacent to and obliquely above and in front of the bearing portion 22a, and includes a concave portion 222 having an arcuate concave curved surface. The recess 222 is arranged so that its front end (the right end in FIG. 6) is located diagonally above the rear end (the left end in FIG. 6), whereby the recess 222 opens diagonally upward on the rear side. Having a structure. Further, the lowest point of the concave portion 222 is arranged so as to be higher than the same point of the concave portion 220, and the rear end of the concave portion 222 is located at the bearing 22a.
The concave portion 220 is disposed at a position higher than the front end, and the both ends are connected by a straight portion 223 that descends rearward.

Depth of recess 222 (depth vertically downward from the front end of recess 222 to the lowest point in this embodiment)
Is formed smaller than the depth of the bearing portion 22a (in this embodiment, the vertical depth from the front end of the concave portion 220 to the lowest point) so that the shaft end 61 can quickly contact the concave portion 222. Have been. Also, the recess 222
Is formed to have a larger radius of curvature than the recess 220 of the bearing portion 22a in order to facilitate positioning of the shaft end 61 in the recess 222. Further, the recess 222
The portion near the rear end is formed so as to be substantially horizontal to facilitate movement of the roll paper shaft 6 from the temporary placing portion 22b to the bearing portion 22a.

Next, referring to FIG.
The roll paper shaft 6 set to 2 will be described in detail. The cylindrical roll paper shaft 6 is provided with left and right roll paper holders 22, 22.
(See FIGS. 2 and 3) Shaft ends 61, 6
1 is provided. The right shaft end 61 in FIG. 8 is set on the right roll paper holder 22, and the left shaft end 61 in FIG. 8 is set on the left roll paper holder 22.

In the vicinity of the right shaft end 61, a disk-shaped handle portion 62 for manually rotating the roll paper shaft 6 is fixed. The diameter of the handle portion 62 is
In order to facilitate the rotation operation and to function as a stopper described later, it is preferable that the diameter of the roll paper 5 is set to be larger than the diameter of the roll paper 5 to be mounted. The handle portion 62 is integrally formed with a cylindrical roll paper core receiving portion 62 a protruding toward the center of the roll paper shaft 6.

In the vicinity of the left shaft end 61, the roll paper 5
Is attached, a stopper (movable paper stopper) 63 for abutting the left end of the roll paper 5 is fitted and fixed.

After the roll paper 5 is inserted by the operator into the roll paper shaft 6 so as to be wound leftward when viewed from the handle portion 62 side, the core 5a is fitted into the roll paper core receiving portion 62a, and the roll paper 5 is inserted. 5 is pushed in until the right end thereof contacts the handle portion 62. Thereafter, the stopper 63 is fitted into the roll paper shaft 6 until it comes into contact with the left end of the roll paper 5,
Fixed. As a result, both ends of the roll paper 5 are stopped by the handle portion 62 and the stopper 63, and stable paper feeding is possible. Therefore, the handle portion 62 is used not only for manually rotating the roll paper shaft 6 but also as a stopper (fixed paper stopper) for stopping the right end of the roll paper 5.

Next, referring again to FIGS. 6 and 7, an operation of setting the roll paper shaft 6 (hereinafter simply referred to as “roll paper shaft 6”) on which the roll paper 5 is mounted to the roll paper holder 22 is performed. Will be described.

When the roll paper cover 21 is opened as shown in FIG. 6, the roll paper shaft 6 (shaft end 61)
Is first set in the temporary storage section 22b (the left and right temporary storage sections 22b, 22b) by the operator. Temporary holder 22b
Is located in front of and above the bearing portion 22a and has a small depth, as described above, so that the setting operation to the temporary placing portion 22b requires the roll paper shaft 6 to be connected to the bearing portion 2a.
This can be performed more easily than in the case of setting directly to 2a.

Subsequently, the roll paper shaft 6 is set on the bearing portion 22a by the operator so as to roll down from the temporary placing portion 22b to the bearing portion 22a. Temporary holder 22
b is disposed obliquely above the bearing portion 22a and the linear portion 223 is formed so as to descend toward the bearing portion 22a, so that the operator can use the gravity to roll down with a small force. Can be.

As described above, the provision of the temporary placement portion 22b in the roll paper holder 22 facilitates the setting operation of the roll paper shaft 6, thereby reducing the burden on the operator. In particular, in the large printer 1 according to the present embodiment, the roll paper 5 becomes heavy, so that the setting operation of the roll paper shaft 6 is facilitated,
Reducing the burden on the operator means that large printers 1
It becomes important from the viewpoint of making it easy to use.

The roll paper shaft 6 is connected to the roll paper holder 22.
Also, when the roll paper shaft 6 is taken out, the roll paper shaft 6 can be taken out after the roll paper shaft 6 is once placed on the temporary placing portion 22b from the bearing portion 22a, so that the operation at the time of taking out is also easy and the burden on the operator can be reduced.

After the roll paper shaft 6 has been set in the roll paper holder 22, the roll paper 5 mounted on the roll paper shaft 6 is fed obliquely downward from the upper part through the front part.
Is sent to After printing or when replacing roll paper,
The unwound roll paper 5 is taken up and the roll paper shaft 6
Is taken out of the roll paper holder 22. The unwinding operation and the winding operation of the roll paper 5 are performed by rotating the roll paper shaft 6. At this time, since the roll paper shaft 6 is provided with the handle portion 62, FIG.
As shown in (1), the operator can perform a rotating operation by holding the handle portion 62. As described above, since the operator's hand 7 does not directly touch the roll paper 5, it is possible to prevent sweat, sebum, dirt, and the like of the hand from adhering to the roll paper 5, thereby preventing deterioration of printing quality. it can. In addition, handle part 6
Since the disk 2 has a disk shape, there is also an advantage that the rotating operation can be easily performed.

Although the handle 62 is attached to the right side of the roll paper shaft 6 so that a right-handed operator can easily operate the handle 62, it can be attached to the left side.

Next, the roll paper cover 21 will be described in detail with reference to FIGS. 4 to 6 and FIG. The roll paper cover 21 is integrally formed of a transparent synthetic resin material (for example, plastic) so that the roll paper 5 set inside can be seen from the outside. The roll paper cover 21 is formed integrally with the cover side walls 21c, 21c, and between the cover side walls 21c, 21c, and has a front end portion 21a and a curved surface portion 21b that cover the roll paper 5.
It is composed of

The cover side wall 21c is manually and rotatably attached to the side wall 20 (see FIGS. 2 and 3) of the main body of the sheet feeding section 2. The rotation center B is the center (axis) of the roll paper shaft 6 (see FIG. 8) set on the bearing portion 22a.
A is provided at substantially the same position as A (more specifically, at a position slightly obliquely rearward of the center A).

The front end 21a is formed as a plane substantially parallel to the paper guide 33 provided inside the printing unit 3 when the roll paper cover 21 is closed. Therefore, the inner surface of the front end 21a is also formed substantially parallel to the paper guide 33.

The curved surface portion 21b is formed at a portion extending from the front end portion 21a toward the rear side of the roll paper cover 21 and has a shape along the cylindrical shape of the roll paper 5 (in the closed state shown in FIG. Cylindrical shape centered on the axis A of the shaft 6).

A notch 21 d is formed at the rear end of the roll paper cover 21, and the roll paper 5
Is not provided, and is open.

The roll paper cover 21 is opened when the roll paper is set in the roll paper holder 22 or when the set roll paper is taken out, and is closed when printing or when the large printer 1 is not used. State.

Roll paper cover 21 closed by operator
When the roll paper cover 21 is manually rotated to the rear side while holding a part of the roll paper cover 21, the roll paper cover 21 transitions from the state shown in FIG. 4 to the state shown in FIG. Becomes When the roll paper cover 21 in the opened state is manually turned forward, the roll paper cover 21 is rotated.
Changes from the state shown in FIG. 6 to the state shown in FIG. 4 through the state shown in FIG. 5, and becomes a closed state.

The closed position shown in FIG. 4 (hereinafter referred to as “closed end position”) and the open position shown in FIG. 6 (hereinafter referred to as “opened end position”) are both used.
The rotation of the roll paper cover 21 is defined by a stopper or the like (not shown) that restricts the rotation.

In this opening / closing operation (that is, rotating operation), the roll paper cover 21 has a curved surface portion 21 b along the cylindrical shape of the roll paper 5, and the rotation center B is set to the center A of the roll paper shaft 6. Since the roll paper cover 21 is located at substantially the same position, the roll paper cover 21 opens and closes substantially along the cylindrical surface of the roll paper 5. Thereby, the space occupied by the cover 21 due to the opening and closing of the roll paper cover 21 can be reduced.

Further, since the rotation center B is located slightly deviated rearward (obliquely downward) from the center A, the roll paper cover 21 moves from the closed state to the open state, and accordingly, the front end thereof moves from the closed state to the open state. The portion 21a and the curved surface portion 21b are displaced rearward. Thus, in the opened state, the roll paper setting / removal opening formed on the front surface of the paper feeding unit 2 (between the front end 21a and the lower body of the paper feeding unit 2 (or the upper body of the printing unit 3)). The opening formed in FIG.
As shown in FIG. 3, the roll paper 5 can be formed large, so that the roll paper 5 can be easily set and taken out.

On the other hand, at the rear end of the roll paper cover 21,
Since the notch 21d is provided, the roll paper cover 2
3, the rear end of the roll paper cover 21 and the rear of the main body of the paper feeding unit 2 (or the printing unit 3) as shown in FIG.
(A rear portion of the main body). Thereby, when the roll paper cover 21 is opened, it is possible to prevent the operator from danger of pinching his / her hand with the roll paper cover 21. Therefore, the cutout portion 21d is formed over a length that allows the operator not to pinch or pass the hand when the roll paper cover 21 is opened (that is, the length in the circumferential direction in FIG. 4). It is preferred that

An arc-shaped pressing portion 21 is provided on the cover side wall 21c.
0 is formed integrally with the cover side wall 21c. The arc-shaped pressing portion 210 is composed of a rail portion 210d having an arc shape centered on the rotation center B, and a connection portion 210c formed integrally with the cover side wall 21c at the center of the rail portion 210d. ing. Rail part 210d
Is connected to and supported by the body of the cover side wall 21c by the connection portion 210c, while the surrounding portion other than the connection portion 210c is surrounded by an arc-shaped slit 211 formed through the cover side wall 21c. Rail part 210d
Recesses 210a and 210b are formed at both ends of the outer peripheral portion of. A pin (a rod-shaped member) 20a is fixed to a side wall 20 (see FIGS. 2 and 3) of the main body of the paper feeding unit 2,
Slit 211 located on the outer peripheral side of rail portion 210d
Is inserted.

The position and the circumferential length of the rail portion 210d are such that when the roll paper cover 21 is located at the end position in the closed state, the pin 20a is fitted into the recess 210a and the roll paper cover 21 is opened. The pin 20a is set so as to fit into the recess 210b when located at the state end position.

The rail 210d is configured to press the pin 20a outward in the radial direction by its outer peripheral portion. In the present embodiment, the pressing force utilizes the restoring force of the rail portion 210d which is bent by being pressed inward in the radial direction by the pin 20a and which attempts to return to the original state from the bent state. For this reason, the outer peripheral portion of the rail portion 210d in a state where the pin 20a is not pressed is formed to bulge radially outward from a state where the pin 20a is pressed. That is, the distance from the center B to the outer periphery of the rail 210d is greater than the distance from the center B to the surface (pressing point) of the pin 20a. However, while both ends of the rail portion 210d bend well, the center portion does not bend as much as both ends due to the presence of the connection portion 210c. Therefore, the swelling amount at the center portion is smaller than the swelling amount at both ends. Is set.

Therefore, when the roll paper cover 21 rotates, the outer peripheral portion of the rail portion 210d slides while being pressed against the pin 20a. As a result, a frictional resistance (sliding resistance) that suppresses rotation is generated between the rail portion 210d and the pin 20a, and the frictional resistance is reduced by the roll paper cover 21.
Acts to reduce the rotation speed or stop the rotation.

As a result, the roll paper cover 21 naturally rotates due to gravity and collides with the operator, or the roll paper cover 2
The operator can be prevented from being injured by holding his hand between the main body (or the printing unit 3). Also, the roll paper cover 21
Can be prevented from colliding with the main body of the paper feeding unit 2 (or the printing unit 3) and being damaged. In particular, in the case of a large-sized printer, the roll paper cover 21 becomes large and accordingly heavy,
It becomes more important to prevent such injuries and breakage.

Since the rail portion 210d is configured to press the pin 20a, the pin 20a is
At the closed end position and the open end position, they fit into the recesses 210a and 210b, respectively. As a result, the roll paper cover 21 is locked by the pin 20a at the end position in the closed state and the end position in the open state, and does not naturally rotate due to gravity. As a result, similarly to the above, it is possible to prevent the operator from being injured by the natural rotation and the roll paper cover 21 from being damaged. Further, since the roll paper cover 21 maintains the closed state and the open state, it is possible to stably feed the roll paper in the closed state (particularly, feed the cut sheet using the front end 21a). In addition, the roll paper can be set or removed calmly and reliably in the open state.

Further, the arc-shaped pressing portion 210 is connected to the rail portion 2.
10d, even if the arc-shaped pressing portion 210 is deformed due to a temperature change, this deformation is not caused by the rail portion 2.
It can be absorbed by the bending of 10d. Further, although the sliding frictional force slightly changes due to the temperature change, the sliding frictional force can be stably generated regardless of the temperature change.

As described above, the locking of the pin 20a by the recesses 210a and 210b keeps the roll paper cover 21 closed and open, and the operator does not apply too much force. Is preferably configured to be able to be released.

The inner surface of the front end 21a and the upper surface of the paper guide 33 of the paper feed unit 3 are spaced apart from each other. The distance L1 between the two is determined when the roll paper 5 is fed by the paper feed roller 36 toward the paper feed unit 3 (the print head 35 mounted on the paper guide unit 33 and the carriage 34).
Does not come into contact with the front end 21a, and when the fed roll paper 5 is returned to the paper feeding unit 2 by the paper feed roller 36 (for example, at the time of a cueing operation), the returned roll paper 5 is moved to the front end. It is set to a distance that comes into contact with the portion 21a and is guided by the curved surface portion 21b formed behind the portion 21a.

As a result, when the roll paper 5 is fed, an increase in the transport resistance caused by the roll paper 5 contacting the roll paper cover 21 can be prevented, and the deterioration of print quality due to the increase in the transport resistance can be prevented. .

On the other hand, when returning the roll paper 5 to the paper feed unit 2,
The returned roll paper 5 is guided from the front end portion 21a to the curved surface portion 21b behind it, further guided by the curved shape of the curved surface portion 21b to the rear side, and is formed as a "slack" 5b hanging downward at the rear side. You. Thereby, the returned roll paper 5 can be prevented from staying near the front end 21a, and the occurrence of “bending” due to the stay can be prevented. As a result, it is possible to prevent the roll paper from being undesirably bent, bent or wrinkled.

Further, on the rear side of the roll paper cover 21, as described above. Notch 21d is formed,
The notch 21d acts to allow the "slack" 5b to escape to the outside. Thereby, the formation of the "slack" 5b is assisted, and the roll paper 5 can be guided more smoothly from the front end 21a to the rear side via the curved surface 21b, and the occurrence of "bending" is further reduced. It can be effectively prevented.

The distance L1 is preferably, for example, a distance between 2 [mm] and 7 [mm].

The gap 25 described above is formed between the front end of the front end portion 21a and the upper end of the paper guide portion 33 so that the operator can put his hand in opening and closing the roll paper cover 21. Has become.

The vertical length L2 of the gap 25 allows the operator to insert his / her hand when opening / closing the roll paper cover 21 and to prevent the operator from pinching his / her hand when closing. As described above, when the roll paper 5 is returned to the paper feed unit 2, the length of the roll paper 5 is set so as to be guided from the front end 21a to the curved surface 21b without bending. Such a length L2 is 15 [mm] to 40 [mm] (more preferably, 20 [mm] to 25 [mm].
[Mm]) is preferred.

The front end 21a is also used as a guide surface for placing cut-sheet paper on its upper surface and guiding it to the printing unit 3.
For this reason, a gap (opening) 37 for feeding cut paper to the paper guide 33 is formed on the upper surface of the printing unit 3 which is an extension of the front end 21a, and is placed on the upper surface of the front end 21a. The cut paper is fed from the gap 37 toward the paper guide 33 and the paper feed roller 36.

At the time of this feeding, the inner surface (back surface) of the front end portion 21a is arranged at a distance L1 from the paper guide portion 33, so that the upper surface (front surface) of the front end portion 21a and the paper guide portion 3 are separated.
Between 3, the cut sheet is placed in a concavely warped state. As a result, the leading end (lower end) of the cut sheet easily comes into contact with the paper guide section 33, and the cut sheet can be fed reliably.

[0075]

According to the present invention, the roll paper holder is provided with a temporary placing portion, and the temporary placing portion is disposed in front of the bearing portion. This is easier than setting directly on the bearing part, and the burden on the operator can be reduced. Further, once the roll paper shaft is placed on the temporary placing portion, the operator can release the roll paper, so that the burden on the operator can be reduced. Furthermore, the setting of the roll paper from the temporary storage section to the bearing section is performed by moving the roll paper from the front to the rear, and this operation is easier than setting the roll paper directly to the bearing section. Thus, the burden on the operator can be reduced.

When the roll paper is to be taken out from the roll paper holder, the roll paper can be taken out from the bearing portion after being temporarily placed on the temporary placement portion, so that the operation for taking out the roll paper becomes easy, and the burden on the operator is reduced. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an overall configuration of a large printer.

FIG. 2 is a front view of the paper feeding unit with a roll paper cover opened.

FIG. 3 is a plan view of the large printer with the roll paper cover opened.

FIG. 4 is a left side view (partially sectional view) of the right cover side wall and the right roll paper holder in a state where the roll paper cover is closed.

FIG. 5 is a left side view (partially sectional view) of the right cover side wall and the right roll paper holder in a state where the roll paper cover is being opened and closed;

FIG. 6 is a left side view (partially sectional view) of the right cover side wall and the right roll paper holder in a state where the roll paper cover is opened.

FIG. 7 is a plan view of a roll paper holder.

FIG. 8 is a perspective view showing a roll paper shaft and a roll paper mounted on the roll paper shaft.

FIG. 9 is an operation explanatory view of a roll paper shaft set in a roll paper holder.

FIG. 10 is a left side sectional view showing a sheet feeding unit and a part of a printing unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Large printer 2 Paper supply part 5 Roll paper 6 Roll paper shaft 22 Roll paper holder 22a Bearing part 22b Temporary placement part 61 Shaft end part 220,222 Recess 223 Linear part

Claims (7)

[Claims] An image forming apparatus includes a bearing provided in a paper feeding section of a large-sized printer, the roll supporting a roll paper shaft to which the roll paper is attached, when the roll paper is fed, and formed by a concave portion opened upward. A roll paper holder for a large printer, comprising a temporary placement portion for temporarily supporting the roll paper shaft in front of the bearing portion. 2. The roll paper holder according to claim 1, wherein the temporary placing portion is formed by a concave portion having a smaller depth than the bearing portion and opening upward. 3. The roll paper holder according to claim 1, wherein the temporary placing portion is formed by a concave portion which is opened upward and larger than the bearing portion. 4. The temporary storage part according to claim 2, wherein the temporary storage part is disposed obliquely above and adjacent to the bearing part, and the front end of the temporary storage part is disposed obliquely above the rear end. And a rear end of the temporary placement portion is connected to a front end of the bearing portion. 5. The roll paper holder according to claim 4, wherein a portion near the rear end of the temporary placing portion is substantially horizontal. 6. The roll paper holder according to claim 5, wherein the temporary placing portion is formed by an arc-shaped concave portion. 7. A large-size printer comprising the roll paper holder of the large-size printer according to any one of claims 1 to 6.