JP2003212389A - Printing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive printing device capable of detecting whether machine glazed paper is set in the proper direction or in the opposite direction in simple constitution. <P>SOLUTION: A plurality of opening parts 30 is concentrically formed on a rotary disc 21. Size of these opening parts 30 gradually increases in the clockwise direction. When a cover 12 is closed, a driving part 22 pressurizes a peripheral surface of the rotary disc 21 on a peripheral surface of the machine glazed paper 10 set on a sheet setting part 11. In this state, the machine glazed paper 10 is drawn out by rotating a drawing roller 13. At this time, the rotating direction of the rotary disc 21 is detected in accordance with whether light receiving time of light on a light receiving element of an optical sensor 23 gradually increases or gradually decreases, and whether the machine glazed paper is set in the proper direction or set in the opposite direction is judged from the rotating direction of the rotary disc 21. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus for printing characters and images on roll paper set in a main body, and more particularly to printing for detecting whether or not the orientation of the roll paper set in the main body is proper. Regarding the device.

[0002]

2. Description of the Related Art Conventionally, there has been a printing apparatus which uses roll paper wound in a roll shape as printing paper. Most of the printing apparatuses of this type are of a thermal transfer type using a thermal head, and use a roll paper obtained by winding a thermal paper in a roll shape as a printing paper.

By the way, in this type of printing apparatus, the user may mistakenly set the roll paper in the opposite direction to the printing apparatus. When the roll paper is set in the reverse direction, the surface with which the thermal head contacts (hereinafter referred to as the printing surface) is reversed, so that characters and images are not printed. In such a case, the user needs a great deal of labor and time to find out the cause of the non-printing of characters or images. Therefore, there is a problem that the operability is not good.

In order to solve this problem, there has been proposed a printing apparatus provided with a structure for detecting whether the roll paper is set in the proper direction or the reverse direction with respect to the main body. For example, in Japanese Unexamined Patent Publication No. 8-333039, a rotating plate attached to a rotating shaft that is rotated by a roll paper set in a main body via a one-way clutch is provided, and when the roll paper rotates (drawing the roll paper There is disclosed a configuration for detecting whether the roll paper is set in an appropriate direction or in the opposite direction depending on whether the rotating plate rotates.

[0005]

However, since the structure disclosed in the above publication uses a one-way clutch, the number of parts is large and the structure is complicated.
There has been a problem that the apparatus main body becomes expensive as the number of assembling steps increases.

An object of the present invention is to provide an inexpensive printer which detects whether the roll paper is set in the proper direction or the reverse direction with a simple structure.

[0007]

The printer according to the present invention comprises:
The following configuration is provided to solve the above problems. (1) A paper setting unit for setting roll paper wound in a roll shape, and a paper feed roller holding the paper pulled out from the roll paper set in the paper setting unit are rotated in a predetermined direction. A paper feeding unit for pulling out the roll paper set in the paper setting unit, a printing unit for printing characters and images on the paper pulled out by the paper feeding unit, and a roll paper set in the paper setting unit And a set direction detecting unit for detecting whether or not the direction is proper, the set direction detecting unit has three or more openings on a concentric circle so that the size gradually increases. And a light-emitting element and a light-receiving element that are arranged to face each other with a position through which the opening passes when the rotation plate is rotated, Lap The has a a pressing means for pressing the peripheral surface of the roll sheet set in the paper setting portion.

In this construction, the peripheral surface of the rotary plate rotatably arranged is pressed against the peripheral surface of the roll paper set in the paper setting section by the pressing means. When the roll paper is pulled out by the paper feeding unit, the roll paper set in the main body rotates. The rotating plate is rotated by the rotation of the roll paper. The rotary plate is formed with three or more openings on a concentric circle so that the size of the rotary plate gradually increases.

The sizes of the adjacent openings may be the same or different.

When the rotating plate rotates, the light receiving state of the light receiving element gradually becomes longer or shorter depending on the rotating direction. Therefore, when the rotating plate is rotated, the rotation direction of the rotating plate can be detected by detecting the time change of the light receiving state of the light receiving element, and the rotation direction of the rotating plate can be detected from the rotating direction of the rotating plate. By knowing the rotation direction, it is possible to detect whether the roll paper is properly set or the reverse direction.

As described above, since the rotation direction of the roll paper can be detected with a simple structure without using the one-way clutch, the number of assembling steps can be suppressed, and the cost of the main body can be reduced.

When it is detected that the roll paper is set in the opposite direction to the main body, the fact may be displayed on the display unit or an alarm sound may be output to notify the user.

(2) A paper setting unit for setting roll paper wound in a roll shape, and a paper feed roller for holding the paper pulled out from the roll paper set in the paper setting unit in a predetermined direction. And a paper feed unit that pulls out the roll paper set in the paper setting unit,
A printing unit that prints characters and images on the paper pulled out by the paper feeding unit, and a set direction detection unit that detects whether or not the orientation of the roll paper set in the paper setting unit is proper In the printing apparatus, the set-direction detecting unit has three or more openings formed on concentric circles so that the distance between them gradually increases, and when the rotating plate is rotatably arranged and the rotating plate is rotated. A light-emitting element and a light-receiving element that are arranged to face each other across the position where the opening passes, and a pressing unit that presses the peripheral surface of the rotating plate against the peripheral surface of the roll paper set in the paper setting unit. And have.

This structure is substantially the same as the above-mentioned (1), but is different in that three or more openings are concentrically formed on the rotary plate so that the distance between them gradually increases. There is. The size of the openings may be the same,
It may also have different sizes.

In this structure, when the rotary plate rotates, the time in the non-light receiving state of the light in the light receiving element gradually becomes longer or shorter depending on the rotating direction. Therefore, when the rotary plate is rotated, the rotational direction of the rotary plate can be detected by detecting the time change of the non-light receiving state of the light in the light receiving element, and the roll paper is set properly as in the above (1). It can detect whether or not it is set in the opposite direction.

(3) The pressing means is enabled so that the peripheral surface of the rotary plate is pressed against the peripheral surface of the roll paper set in the paper setting section, or the pressing means is disabled. A switching means is provided for switching whether the peripheral surface of the rotary plate is kept away from the peripheral surface of the roll paper set in the paper setting section.

With this structure, the peripheral surface of the rotary plate can be separated from the peripheral surface of the roll paper set in the paper setting section by the switching means. With this, after confirming that the roll paper is set in the proper direction, keep the peripheral surface of the rotary plate away from the peripheral surface of the roll paper set in the paper setting section. ,
It is possible to prevent the roll paper from being damaged by the rotating plate.

(4) When the cover of the paper setting section changes from the open state to the closed state, the switching means activates the pressing means, activates the paper feeding section, and rolls out the roll paper. After detecting whether the orientation of the roll paper set in the paper setting unit is proper, the pressing means is disabled by the switching means.

In this structure, the timing at which the cover of the paper setting section changes from the open state to the closed state is determined as the timing at which the roll paper is set on the main body, and the peripheral surface of the rotary plate is set on the main body. By pressing the roll paper against the peripheral surface of the roll paper and pulling out the roll paper, the roll paper is rotated to detect whether the roll paper is set in the proper direction or the reverse direction. When the direction in which the roll paper is set is detected, the peripheral surface of the rotary plate is separated from the peripheral surface of the roll paper set in the main body.

Therefore, the user does not have to perform a switching operation such that the peripheral surface of the rotary plate is pressed against the peripheral surface of the roll paper set in the main body or is separated from the peripheral surface of the roll paper. Since it is good, the operability for the user can be improved.

Further, at the timing when the cover changes from the open state to the closed state, it is detected whether the roll paper is set in the proper direction or the reverse direction, so that the roll paper is set in the reverse direction. It is possible to almost certainly prevent the printing from being performed in the state of being present. When it is detected that the roll paper is set in the opposite direction to the main body, the fact may be displayed on the display unit or an alarm sound may be output to notify the user.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION A printing device according to an embodiment of the present invention will be described in detail below.

FIG. 1 is a schematic block diagram showing the configuration of a printing apparatus according to an embodiment of the present invention. The printing apparatus 1 of this embodiment includes a control unit 2 that controls the operation of the main body, a printing unit 3 that prints characters and images on the roll paper set in the main body, and pulls out the roll paper set in the main body. A paper feeding unit 4 for carrying, a receiving unit 5 for receiving characters and images to be printed by the printing unit 3, a setting direction detecting unit 6 for detecting the setting direction of roll paper set in the main body, and an operating state of the main body. And a display unit 7 that displays the setting direction of the roll paper detected by the setting direction detection unit 6, and the like.

In the printer 1, when the receiving unit 5 receives the print data such as characters and images, the paper feeding unit 4 pulls out the roll paper set in the main body, and the roll paper is printed by the print unit 3 having a print head. Send to. The printing unit 3 prints characters and images based on the print data received by the receiving unit 5 on the paper sent by the paper feeding unit 4. The roll paper set in the main body is a roll of heat-sensitive paper,
The print head of the printing unit 3 is a thermal head.

FIG. 2 is a view showing a state in which the roll paper is set in an appropriate direction with respect to the main body, and FIG. 3 is a view showing a state in which the roll paper is set in the reverse direction with respect to the main body. is there.

As shown in the figure, the roll paper 10 which is a printing paper is stored (set) in a paper setting section 11 whose cross section is semicircular. The paper setting unit 11 is provided with a cover 12 that can be opened and closed. The printer 1 is configured to detect the open / closed state of the cover 12 by a micro switch (not shown). Micro switch covers 12
Is attached at a position where it is pressed and turned on when the cover 12 is in the closed state, and is turned off without being pressed when the cover 12 is in the opened state.

The end portion of the roll paper set in the paper setting unit 11 is pulled out, and is sandwiched by the pull-out rollers 13 and 14 arranged to face each other. Drawer roller 13
Is rotated counterclockwise by a motor (not shown) when the roll paper 10 is pulled out. At this time, the pull-out roller 14 is driven by the pull-out roller 13 to rotate clockwise.

In this embodiment, the drawing rollers 13, 1
When the roll paper 10 is pulled out by 4, the roll paper 10 rotates clockwise if it is set in the paper setting unit 11 in the proper direction (direction shown in FIG. 2), and is rotated in the reverse direction to the paper setting unit 11. If it is set to (the direction shown in FIG. 3), it rotates counterclockwise. Reference numeral 15 shown in the drawing is a print head (thermal head).

Further, 21 is a rotating plate which is rotatably attached, and 22 is a drive unit which vertically moves the rotating shaft of the rotating plate 21. When the drive unit 22 moves the rotary shaft of the rotary plate 21 upward (FIG. 2 (A), FIG. 3 (A)).
(State shown in FIG. 3), an opening is formed in the paper setting unit 11 so that the peripheral surface of the rotary plate 21 is pressed against the peripheral surface of the roll paper 10 set in the paper setting unit 11. When the roll paper 10 is pulled out by the pull-out rollers 13 and 14, the winding portion of the roll paper 10 set in the paper setting portion 11 is pulled forward (right side in FIGS. 2 and 3), so that the opening By providing the portion in front of the paper setting portion 11, the rotational force of the roll paper 10 is applied to the rotary plate 21.
More reliably. The rotary plate 21 rotates when the rotational force of the roll paper 10 is transmitted.

When the rotating shaft of the rotary plate 21 is moved downward by the drive unit 22 (the state shown in FIGS. 2B and 3B), the peripheral surface of the rotary plate 21 is placed on the paper setting unit 11. Move away from the peripheral surface of the set roll paper 10.

As shown in FIG. 4, the rotary plate 21 has a plurality of openings 30 formed concentrically. The sizes of the plurality of openings 30 gradually increase in the clockwise direction.

The sizes of the adjacent openings 30 are the same.

Further, reference numeral 23 shown in the drawing is an optical sensor in which a light emitting element and a light receiving element are arranged so as to face each other. Optical sensor 23
Is in the state shown in FIG. 2 (A) and FIG. 3 (A),
When the rotary plate 21 rotates, the plurality of openings 30 of the rotary plate 21 are attached at positions where they pass through the facing surfaces of the light emitting element and the light receiving element.

In the printing apparatus 1 of this embodiment, when the orientation of the roll paper 10 set in the paper setting unit 11 is detected, the drive unit 22 moves the rotary shaft of the rotary plate 21 upward to move the rotary plate. The peripheral surface of 21 is pressed against the peripheral surface of the roll paper 10 set in the paper setting unit 11, as shown in FIG.
(A), the state shown in FIG. Normally, the drive unit 22 moves the rotary shaft of the rotary plate 21 downward, and the peripheral surface of the rotary plate 21 is separated from the peripheral surface of the roll paper 10 set in the paper setting unit 11, as shown in FIG. B), FIG.
This is the state shown in (B).

The printer 1 of this embodiment detects the orientation of the roll paper 10 set in the paper setting unit 11 at the timing when the cover 12 of the paper setting unit 11 changes from the open state to the closed state. The user opens the cover 12 in most cases to replace the roll paper 10.

The process for detecting the orientation of the roll paper 10 set in the paper setting unit 11 will be described below. FIG. 5 is a flowchart showing a process of detecting the orientation of the roll paper set in the paper setting unit. The printer 1 starts this process when it detects that the cover 12 of the paper setting unit 11 has changed from the open state to the closed state. The open / closed state of the cover 12 is detected by the microswitch as described above.

When the printer 1 detects that the cover 12 has changed from the open state to the closed state, the driving unit 22 moves the rotary shaft of the rotary plate 11 upward, and the peripheral surface of the rotary plate 21 is moved to the paper setting unit. The peripheral surface of the roll paper 10 set in 11 is pressed (s1). The printer 1 rotates the pull-out roller 13 in the counterclockwise direction, and pulls out the pull-out rollers 13 and 14
Pull out the roll paper 10 sandwiched by (s2).

Here, the roll paper 10 is the paper setting section 11
If the roll paper 10 is set in the proper orientation,
Rotates clockwise in the paper setting unit 11. Conversely,
When the roll paper is set in the paper setting unit 11 in the opposite direction, the roll paper 10 rotates counterclockwise in the paper setting unit 11.

Further, since the winding portion of the roll paper 10 located in the paper setting portion 11 is pulled forward by the pull-out rollers 13 and 14, the rotary plate 21 is pressed against the roll paper 10 with sufficient pressing force. . As a result, the rotational force of the roll paper 10 can be reliably transmitted to the rotary plate 21, and the rotary plate 21 can be rotated.

The printer 1 detects whether the rotary plate 21 is rotating clockwise or counterclockwise (s3). The rotation direction of the rotary plate 21 is detected by the following method.

The printer 1 receives the light in the light receiving element of the optical sensor 23 while the rotary plate 21 is rotating.
The non-light-receiving change pulse is detected. A plurality of openings 30 are formed in the rotary plate 21 so as to gradually increase in the clockwise direction. Therefore, when the rotary plate 21 is rotating in the counterclockwise direction, the light receiving and non-light receiving change pulses in the light receiving element of the optical sensor 23 are gradually shortened as shown in FIG. 6 (A). It will become. On the contrary, when the rotary plate 21 is rotating in the clockwise direction, the change pulse of light reception and non-light reception in the light receiving element of the optical sensor 23 is as shown in FIG.
As shown in (B), the light receiving time gradually becomes longer.

The printer 1 determines that the rotary plate 1 is rotating counterclockwise if the light receiving time of the light receiving element is gradually shortened, and conversely the light receiving time is gradually lengthened. If so, it is determined that the rotary plate 21 is rotating clockwise.

When the printer 1 detects the rotation direction of the rotary plate 21 in s3, it stops the rotation of the pull-out roller 13 and stops the pulling out of the roll paper 10 (s4). The printer 1 moves the rotary shaft of the rotary plate 21 downward by the drive unit 22 and changes the peripheral surface of the rotary plate 21 away from the peripheral surface of the roll paper 10 (s5).

The printing apparatus 1 has the rotary plate 21 detected in s3.
If the rotation direction of is the counterclockwise direction, it is determined that the roll paper 10 is set in the proper direction, the fact is displayed on the display unit 7, and this processing is ended (s6, s7). Conversely,
If the rotation direction of the rotary plate 21 detected in s3 is clockwise, it is determined that the roll paper 10 is set in the reverse direction, the display unit 7 displays that fact, and the present process is terminated (s).
6, s8).

At s8, an alarm is sounded and the roll paper 1
The user may be notified that 0 is set in the opposite direction.

As described above, since the printer 1 of this embodiment detects the orientation of the roll paper 10 set in the paper setting unit 11 with a simple structure that does not use the one-way clutch, the cost of the main body is sufficiently high. It can be suppressed and made inexpensive.

Further, since the rotary plate 21 is only temporarily pressed against the peripheral surface of the roll paper 10 when the cover 12 is closed, the rotary plate 21 does not damage the roll paper 10.

Further, when the cover 12 of the paper setting section 11 changes from the open state to the closed state, the processing shown in FIG. 5 is performed and the roll paper 10 set in the paper setting section 11 is processed.
Since the orientation of the roll paper 10 is detected, the orientation can be reliably detected at the timing when the roll paper 10 is set in the main body, and printing can be prevented from being performed in the state where the roll paper 10 is set in the reverse orientation. Further, since the user does not have to perform the operation of detecting the orientation of the roll paper 10 set in the paper setting unit 11, the user does not feel bothered and the operability of the user is improved. Can be made.

Although the distance between the adjacent openings 30 formed in the rotary plate 21 is the same in the above embodiment, this distance may be different. Further, although the openings 30 are arranged in the clockwise direction so that the sizes thereof gradually increase, the openings 30 may be arranged in the clockwise direction so that the sizes thereof gradually decrease. In this case, when the rotary plate 21 rotates counterclockwise, the optical sensor 2
As shown in FIG. 6B, the light receiving / non-receiving change pulse in the light receiving element of No. 3 gradually increases the light receiving time. On the contrary, when the rotating plate 21 is rotating clockwise, the light receiving element of the optical sensor 23 changes the light receiving / non-receiving change pulse gradually as shown in FIG. 6 (A). It will become. In this case as well, the rotation plate 21 changes from the change in the light receiving time in the light receiving element of the optical sensor 23.
The rotation direction of can be detected.

As shown in FIG. 7, the rotary plate 21 is formed such that the plurality of openings 30 have the same size and the size between adjacent openings 30 gradually increases in the clockwise direction. You may. In this case, when the roll paper 10 is set in the proper direction (when the rotary plate 21 is rotating in the counterclockwise direction), as shown in FIG. When the roll paper 10 is set in the opposite direction (when the rotating plate 21 is rotating in the clockwise direction), the time of is gradually reduced as shown in FIG.
As shown in, the non-light receiving time in the light receiving element of the optical sensor 23 gradually increases. Therefore, the rotation direction of the rotary plate 21 may be detected from the time change of the light receiving element of the optical sensor 23 when no light is received.

The sizes of the openings 30 do not have to be the same. If the sizes of the openings 30 are not the same,
Although the time in the light receiving state varies, there is no problem because the direction in which the roll paper 10 is set is detected depending on whether the non-light receiving time gradually decreases or increases.

Further, the rotary plate 21 has the openings 30 adjacent to each other.
The size of the gap may be gradually reduced in the clockwise direction. In this case, when the roll paper 10 is set in the proper direction (when the rotary plate 21 is rotating in the counterclockwise direction), as shown in FIG. When the roll paper 10 is set in the opposite direction (rotating plate 21
Is rotating clockwise), the non-light receiving time in the light receiving element of the optical sensor 23 is gradually shortened as shown in FIG. Also in this case, the rotation direction of the rotary plate 21 can be detected from the time change of non-light reception in the light receiving element of the optical sensor 23.

[0053]

As described above, according to the present invention, whether the roll paper is set in the proper direction or the reverse direction with respect to the main body with a simple structure that does not use the one-way clutch. Is detected, the cost of the apparatus main body can be reduced.

Also, since the rotary plate is kept away from the peripheral surface of the roll paper except when the orientation of the roll paper is detected, the roll paper is not damaged.

Further, when the cover of the paper setting section changes from the open state to the closed state, the orientation of the roll paper set in the main body is detected, so that the roll paper is set in the reverse direction. It is possible to prevent printing.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a printing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a set state of roll paper in the printing apparatus of this embodiment.

FIG. 3 is a diagram showing a set state of roll paper in the printing apparatus of this embodiment.

FIG. 4 is a diagram showing a rotary plate in the printing apparatus of this embodiment.

FIG. 5 is a flowchart showing a process of detecting a roll paper setting direction in the printing apparatus of this embodiment.

FIG. 6 is a diagram showing a detection waveform of an optical sensor in the printing apparatus of this embodiment.

FIG. 7 is a diagram showing a rotary plate in a printing apparatus according to another embodiment.

FIG. 8 is a diagram showing a detection waveform of an optical sensor in a printing apparatus according to another embodiment.

[Explanation of symbols]

1-printing device 2-Control unit 3-Printing section 4-Paper feeder 5-Receiver 6-Set direction detector 7-Display 10-roll paper 11-Paper setting section 12-Cover 13, 14-drawing roller 15-Print head 21-rotating plate 22-Drive 23-optical sensor 30-opening

Claims (5)

[Claims] 1. A paper setting unit for setting roll paper wound in a roll shape, and a paper feed roller for holding the paper pulled out from the roll paper set in the paper setting unit in a predetermined direction. A paper feeding unit that rotates to pull out the roll paper set in the paper setting unit, a printing unit that prints characters and images on the paper pulled out by the paper feeding unit, and a paper feeding unit that is set in the paper setting unit In a printing apparatus including a set direction detection unit that detects whether or not the orientation of the roll paper is proper, the set direction detection units include three or more concentric circles so that the size thereof gradually increases. A rotatably arranged rotating plate, a light emitting element and a light receiving element that are arranged to face each other with a position where the opening passes when the rotating plate is rotated, Pressing means for pressing the peripheral surface of the rotary plate against the peripheral surface of the roll paper set in the paper setting section; and Whether the peripheral surface of the roll paper is pressed against the peripheral surface of the roll paper or the peripheral surface of the rotary plate is separated from the peripheral surface of the roll paper set in the paper setting section. And a switching means for switching, when the cover of the paper setting section changes from the open state to the closed state, the switching means enables the pressing means,
A printing device that activates the paper feed unit, feeds out the roll paper, and detects whether or not the orientation of the roll paper set in the paper setting unit is proper, and disables the pressing unit by the switching unit. 2. A paper setting unit for setting roll paper wound in a roll shape, and a paper feed roller for holding the paper pulled out from the roll paper set in the paper setting unit in a predetermined direction. A paper feeding unit that rotates to pull out the roll paper set in the paper setting unit, a printing unit that prints characters and images on the paper pulled out by the paper feeding unit, and a paper feeding unit that is set in the paper setting unit In a printing apparatus including a set direction detection unit that detects whether or not the orientation of the roll paper is proper, the set direction detection units include three or more concentric circles so that the size thereof gradually increases. A rotatably arranged rotating plate, a light emitting element and a light receiving element that are arranged to face each other with a position where the opening passes when the rotating plate is rotated, And a pressing unit that presses the peripheral surface of the rotary plate against the peripheral surface of the roll paper set in the paper setting unit. 3. A paper setting unit for setting roll paper wound in a roll shape, and a paper feed roller for holding the paper pulled out from the roll paper set in the paper setting unit in a predetermined direction. A paper feeding unit that rotates to pull out the roll paper set in the paper setting unit, a printing unit that prints characters and images on the paper pulled out by the paper feeding unit, and a paper feeding unit that is set in the paper setting unit In a printing apparatus provided with a setting direction detecting section for detecting whether or not the orientation of the roll paper is proper, the setting direction detecting section has three opening portions on concentric circles so that the intervals gradually increase. One or more rotary plates that are rotatably arranged, a light-emitting element and a light-receiving element that are arranged to face each other across the position where the opening passes when the rotary plate is rotated; A printing device comprising: a pressing unit configured to press the peripheral surface of the plate against the peripheral surface of the roll paper set in the paper setting unit. 4. The pressing means is made effective so that the peripheral surface of the rotary plate is pressed against the peripheral surface of the roll paper set in the paper setting section, or the pressing means is made ineffective. 4. The printer according to claim 2, further comprising a switching unit that switches whether the peripheral surface of the rotary plate is separated from the peripheral surface of the roll paper set in the paper setting unit. 5. When the cover of the paper setting section changes from an open state to a closed state, the switching means enables the pressing means, activates the paper feeding section, and rolls out roll paper to feed the paper. The printing apparatus according to claim 4, wherein the pressing unit is disabled by the switching unit after detecting whether or not the orientation of the roll paper set in the setting unit is proper.