JPH1134308A - Roll detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the presence or absence of a roll of a strip stored in a cassette by a single detecting means. SOLUTION: A lever 111c rocks integrally with a moving portion 111 in accordance with a decrease in a web 7, and a limit switch 171 is arranged in a position where the moving portion 171a is pushed when the lever 111C rocks by a prescribed amount and is turned on. A moving portion 173 usually rocks downward, and the limit switch 171 is turned on by the internal wall of a hollow portion 179. However, the limit switch 171 rocks upward when a cassette is mounted completely, and the internal wall of the hollow section 179 no longer pushes the moving portion 171 a. On such occasion, if an unused portion of the web 7 remains sufficiently in the cassette, the lever 111c does not push the moving section 171a, and the limit switch 171 is turned off. That is, one limit switch 171 helps the cassette to be mounted completely and can detect the sufficient presence of an unused portion of the web 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cassette for accommodating a band wound in a roll shape and using the band when used in a predetermined mounting position. The present invention relates to a roll detection device for detecting the presence or absence of the above-mentioned band.

[0002]

2. Description of the Related Art Conventionally, there has been considered a cassette which accommodates a band wound in a roll shape and uses the band when used at a predetermined mounting position. As this type of cassette, for example, a cassette containing roll paper for maintenance of an ink jet printer is considered, and it is conceivable to clean the head while sequentially feeding out roll paper.

[0003]

However, when detecting the presence or absence of this type of roll paper, it is necessary to first detect whether or not the cassette is mounted at the mounting position.
Then, only when the cassette is mounted at the mounting position, it is possible to detect the presence or absence of the roll paper by bringing the movable portion into contact with the roll paper. in this case,
It is necessary to individually detect the above-described mounting state of the cassette and the state of the roll paper, and two or more detecting means such as sensors are required. For this reason, a device for detecting the presence or absence of this type of roll paper increases the manufacturing cost.

Accordingly, an object of the present invention is to provide a roll detecting device capable of detecting the presence or absence of a roll-shaped band stored in a cassette by one detecting means.

[0005]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, the invention according to claim 1 accommodates a band wound in a roll shape and is mounted at a predetermined mounting position. When the above-mentioned band is used for the cassette,
A roll detecting device for detecting the presence or absence of the band stored in the cassette, wherein the first movable portion moves to a first predetermined position when the cassette is not at the mounting position; A second movable portion that moves to a second predetermined position when the band is run out or is about to run out of an installed cassette; and a first movable portion that moves to the first predetermined position. And detecting means for detecting that the second movable portion has not moved to the second predetermined position.

According to the present invention, the first movable portion moves to the first predetermined position when the cassette is not at the mounting position, and the second movable portion is disposed at the mounting position. When the band has run out or is about to run out of the inserted cassette, the cassette moves to the second predetermined position. Then, the detecting means detects that the first movable part has not moved to the first predetermined position and that the second movable part has not moved to the second predetermined position. Therefore, if the detecting means has performed the above detection, it is understood that the following two conditions are satisfied at the same time. That is, the first movable portion has not moved to the first predetermined position, the cassette is disposed at the mounting position, and the second movable portion has the second movable portion.
At the same time, it is understood that the fact that the band has disappeared from the cassette disposed at the mounting position or that the band has not almost disappeared is satisfied at the same time. Therefore, when the detection means is performing the above detection, it can be determined that a band exists in the cassette.

Therefore, according to the present invention, the presence / absence of the roll-shaped band stored in the cassette can be detected by one detecting means. For this reason, in the roll detection device of the present invention, the manufacturing cost can be favorably reduced. Further, since only one detecting means is required, the size of the apparatus can be reduced as a whole.

In the present invention, since the second movable portion swings depending on the presence or absence of the roll-shaped band, the second movable portion is provided so as to swing in the core direction of the roll. In addition, the presence or absence of a band can be detected with an accuracy that cannot be realized with cut sheets such as cut sheets. This is because the band wound in a roll shape adheres well to the core.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the detecting means is moved to the second predetermined position by the first movable portion moved to the first predetermined position. A switch for outputting or stopping output of a predetermined signal when pressed by at least one of the first movable portion and the second movable portion which is also pressed by the moved second movable portion; It is characterized by:

In the present invention, the detecting means is pressed by the first movable part moved to the first predetermined position and also by the second movable part moved to the second predetermined position, and the first movable part is moved by the first movable part. The switch is configured to output or stop outputting a predetermined signal when pressed by at least one of the unit and the second movable unit. Therefore, the first
When the movable part moves to the first predetermined position or the second movable part moves to the second predetermined position, the switch is pressed by the moved movable part. Therefore, if the switch is not pressed and the switch does not output or stop outputting the predetermined signal, the first movable portion has not moved to the first predetermined position and the second movable portion has not been moved. Second part
It can be seen that it has not moved to the predetermined position.

In the present invention, the above-described detecting means can be provided by such a simple configuration. Therefore, in addition to the effects of the first aspect of the present invention, there is an effect that the size of the device can be further reduced, the configuration of the device can be further simplified, and the manufacturing cost can be more favorably reduced.

The invention described in claim 3 is the first or second invention.
In addition to the configuration described above, the cassette is a cassette mounted on a maintenance mechanism of an inkjet printer, and the band is used for wiping a head surface of the inkjet printer.

In a cassette mounted on a maintenance mechanism of an ink jet printer, a mechanism for detecting the presence / absence of a band housed in the cassette also needs to be miniaturized as much as possible. This is because when the maintenance mechanism becomes large,
This is because not only the printing area of the ink jet printer becomes narrower, but also the area in which the stain due to maintenance occurs becomes wider. On the other hand, in the present invention, the detection mechanism can be favorably miniaturized as described above. Therefore, in the present invention, the effect of the invention described in claim 1 or 2 is more remarkably exhibited.

[0014]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram illustrating a basic configuration of an inkjet printer to which the present invention has been applied. In addition,
The ink jet printer of the present embodiment is a so-called hot melt ink jet printer that melts and ejects solid ink.

As shown in FIG. 1, a head 1 of the ink jet printer is mounted on a carriage 3 (FIG. 8).
It is configured to be movable along the guide shaft 5. The head 1 forms an image by ejecting ink onto a recording paper (not shown) as a recording medium conveyed near the center of the movement range, and forms an image before and after the image formation or at a predetermined timing. The user moves to the maintenance area near the left end (the left end in FIG. 1) and receives a maintenance operation using the roll paper 7.

Next, the structure of the head 1 will be described with reference to FIGS.
This will be described with reference to FIG. 2 is an exploded perspective view of the head 1, FIG. 3 is a top view of the ink tank 10 of the head 1, and FIGS. 4 (a) and (b) are lines BB and C-
It is a C-line cut end view. Further, the configuration of the head 1 is described in detail in Japanese Patent Application No. 8-305325, which should be referred to.

As shown in FIG. 2, the head 1 includes an ink tank 10, a front panel 30, a melting tank 40, a cam 50, and a control board stage 70. The ink tank 10 has an inclined front surface portion 15 for attaching the front panel 30 and a color output (yellow, magenta, cyan) that can store hot melt ink (hereinafter sometimes simply referred to as ink). , Black), an ink tank upper cover 19, and an ink tank heater 17 attached to the back surface of the ink tank 10, as shown in FIG. Further, a communication path 21 that opens downward is provided on the back side of the bottom surface of each of the main chamber 11 and the sub chamber 13 of the ink tank 10.

The main chamber 11 has an L-shape as viewed from above as shown in FIG. 2, and includes a main chamber entrance 21a (FIG. 4B) leading to the communication passage 21 and a front panel 30.
A main chamber outlet 22a (FIGS. 4 (a) and 2) leading to the main chamber and a filter 29 (FIG. 4 (a)) are provided. Filter 29
Is manufactured by sintering stainless steel fibers into a paper shape and then pressing the fibers. Each of the fibers is complicatedly bent and overlapped, and has a passage having a three-dimensional structure (for example, , "Tommy Firek S
S "(registered trademark): manufactured by Tomoegawa Paper Mill Co., Ltd.).

The sub-chamber 13 has a sub-chamber outlet 21b leading to the communication passage 21 and a sub-chamber inlet 22b leading to the front panel 30.
2 and 4 (b), the sub chamber outlet 21b
And a substantially inverted T-shaped valve opening / closing lever 24 which opens one of the sub-chamber inlet 22b when the other is closed.

The valve opening / closing lever 24 is made of an aluminum alloy die-cast, and as shown in FIG. 4B, a lever base 25 provided between the sub-chamber outlet 21b and the sub-chamber inlet 22b is used as a support point. It is mounted so that it can swing. Further, the valve opening / closing lever 24 is provided with pressure-contact valves 27 and 28.
By being urged by the leaf spring 26,
Normally, the pressure contact valve 28 keeps the state where the sub chamber inlet 22b is sealed. Here, the pressure contact surface of the pressure contact valve 27 has a spherical shape, the edge of the corresponding sub-chamber outlet 21b has a tapered surface shape, the pressure contact surface of the pressure contact valve 28 has a planar shape, and the corresponding port of the sub-chamber inlet 22b. The edge has an annularly protruding shape. The pressure-contact valves 27 and 28 are made of silicone rubber and have a Shore hardness of about 40 ° and a heat-resistant temperature of about 200 ° C.
It is.

As shown in FIG. 2, the ink tank upper lid 19 has a front panel cover 19a adapted to the shape of the front panel 30, a sub-chamber cover 19b for covering the sub-chamber 13, and an upper end of the valve opening / closing lever 24. A long hole 19c for exposing the portion 24a and a sub chamber 13 from the melting tank 40.
Ink inlet 1 for supplying hot melt ink to
9d, an air chamber 20 for sending compressed air from a pump 160 to be described later to each main chamber 11, a through hole 20b opened from the air chamber 20 to the side surface of the ink tank 10, and an air chamber for sealing the air chamber 20. And a lid 20a. The air chamber 20 of the ink tank top lid 19 has a through-hole 23 communicating with the main chamber 11, as shown in FIG.

As shown in FIG. 2, the front panel 30 has four nozzle heads 31 on the front surface, and a forward path 35 from each main chamber 11 to each nozzle head 31 on the back surface (FIG. 4A). 4) and a return path 37 (FIG. 4B) from each nozzle head 31 to each sub-chamber 13 is formed. Further, as shown in FIGS. 2 and 4, a cover panel 30a is attached to the back surface of the front panel 30 so as to cover the outward path 35 and the return path 37, and a front panel heater 33 is provided on the back surface of the cover panel 30a. Is attached. As shown in FIG. 4, each main chamber 11 has a forward path entrance 35 a from each forward path 35, and each forward path 35 has a forward path exit 35 b from each forward path 35 to each nozzle head 31.
A return path entrance 37b is provided from 1 to each return path 37, and a return path exit 37a is provided from each return path 37 to each sub-chamber 13.

The nozzle head 31 has a piezoelectric conversion element 38, and ejects the ink supplied via the outward path outlet 35b according to the volume change of the piezoelectric conversion element 38. Further, the ink supplied to the nozzle head 31 can be circulated to the sub chamber 13 via the return path entrance 37b and the return path 37.

The cam 50 is mounted on the ink tank top cover 19 so as to be slidable in the left-right direction in FIG. 3, and the vicinity of the contact surface 50a is projected rightward from above the ink tank top cover 19. I have. The cam 50 has a cam surface 50b.
And a projection 5 provided at the left end of the cam 50.
The cam surface 50 b is normally urged by the spring 51 bridged between the protrusion 2 e and the projection 19 e provided on the ink tank top cover 19 so that the cam surface 50 b does not touch the upper end 24 a of the valve opening / closing lever 24 at normal times. keeping.

The melting tank 40 is, as shown in FIG.
The room is divided into four rooms for each color of black, cyan, magenta, and yellow, and each room has a box shape with an open top so that solid ink can be charged and stored. In addition, the lower part of each room of the melting tank
As shown in (b), a conduction path 47 for guiding the molten ink to the sub-chamber 13 is formed.

Solid ink is supplied to the melting tank 40 from an ink supply device (not shown). The melting tank 40 is provided with a heater, and the solid ink is melted by the heater.
Supply 3 Further, the control board stage 70 includes a control board (not shown), and is mounted on the head 1.

In the head 1 configured as described above, the control substrate stage 70 drives the various heaters 17, 33 and the like to hold the solid ink in a molten state, and then based on the print data and the like, the piezoelectric substrate The conversion element 38 is driven to eject ink. Further, when moving to the maintenance area, the following purging can be executed. In addition, purging is to pressurize the ink in the front panel 30 and the nozzle head 31 from the main chamber 11 side,
Bubbles and dust in the ink that cause non-ejection are sent out of the nozzle together with the ink to the nozzle portion 31a (see FIG. 14), and those in the front panel 30 to the sub-chamber 13 to be filtered. This is an operation of filling clean ink filtered at 29. The bubbles are mixed in the ink when the temperature of the head drops when the power is turned off, the ink solidifies, and the ink is melted when the power is turned on again.
Debris may enter through the nozzle.

That is, when the head 1 moves to the maintenance area, the contact surface 50a of the cam 50 is pressed against the frame 54 (see FIG. 3) of the printer main body, and the hollow cylindrical cap 55 provided on the frame 54 is provided.
Covers the through hole 20b. Then, the cam 50 relatively slides leftward on the ink tank cover 19, and the cam surface 50b pushes the upper end 24a of the valve opening / closing lever 24 downward in FIG. Therefore, the valve opening / closing lever 24 swings around the lever pedestal 25 as a fulcrum, and the pressure contact valve 28 and the sub chamber inlet 2
When the pressure contact with 2b is released and the swinging further proceeds, the pressure contact valve 27 and the sub-chamber outlet 21b are pressed against each other, the sub-chamber inlet 22b is opened, and the sub-chamber outlet 21b is closed.

At this time, the cap 55 is
Since compressed air is supplied from a pump 160, which will be described later, through a pipe 57 connected to the hollow portion of the cap 55, bubbles can be pushed out as follows. That is, the air pressure in the main chamber 11 rises by sending the compressed air. Since the sub-chamber outlet 21b is closed and the sub-chamber inlet 22b is open, the ink containing air bubbles is filtered from the main chamber 11 for bubbles and dust by the filter 29, and the main chamber outlet 22a, the outgoing entrance 35a, the outgoing 3
5. Reach the nozzle head 31 via the outward exit 35b.
Next, the path is divided into a path that is discharged (discharged) from the nozzle portion 31a to the outside and two paths that are directed toward the return path entrance 37b. The respective flow ratios are the forward path 35, the return path 37, and the nozzle portion 31.
It is determined by setting the flow path resistance of a. Return entrance 3
The route on the 7b side is the return route 37, the return route exit 37a, the sub-chamber entrance 2
It is sent to the sub chamber 13 via 2b. As a result, the ink containing bubbles in the forward path 35, the nozzle portion 31a, and the return path 37 is replaced with clean ink.

Thereafter, when the head 1 is moved to the left and the contact surface 50a is separated from the frame 54, the valve opening / closing lever 24
Is not pressed by the cam surface 50b. Then, the valve opening / closing lever 24 swings around the lever pedestal 25 as a fulcrum by the urging force of the leaf spring 26, so that the sub chamber inlet 22b is closed and the sub chamber outlet 21b is opened. As a result, the ink forcedly sent into the sub-chamber 13 due to purging is returned from the communication path 21 to the main chamber 11, so that the liquid levels of the main chamber 11 and the sub-chamber 13 can be at the same level.

When the purging is performed, a part of the ink is forcibly ejected from the nozzle surface 36 of the nozzle head 31. In the present ink jet printer, the roll paper 7 is provided in the maintenance area. The nozzle face 36 can be wiped by the roll paper 7 and the ejected ink can be received. Next, a maintenance unit 100 as a maintenance mechanism for transporting the roll paper 7 and pressing the roll paper 7 against the nozzle head 31 is provided.
Will be described. First, since the roll paper 7 is a consumable item, it is held in the cassette 80 shown in FIGS. 5 and 6, and after use, the entire cassette 80 is replaced or only the roll paper 7 is replaced. The supply to the user is performed by both the cassette 80 and the set of the replacement roll paper 7, and the user's convenience can be selected. FIG. 5 is a left side view showing the configuration of the cassette 80, and FIG. 6 is a longitudinal sectional view thereof.

As shown in FIGS. 5 and 6, the cassette 80
It comprises a lid 81 and a main body 82 which can be opened and closed about a hinge 80a. Inside the main body 82, a pin 83 projecting from the inner wall surface and supporting the unused roll paper 7, a fixed amount feed roller 85 for transporting the roll paper 7, and a winding shaft for winding the transported roll paper 7 87 and a pressure contact plate 89 for pressing the roll paper 7 against the nozzle head 31. The side wall of the main body 82 on which the pin 83 is formed is formed with a substantially U-shaped cut to form a spring portion 82a. For this reason, the pin 83 swings outward when the roll paper 7 is mounted, and returns later by elastic force to return to the hollow core portion of the roll paper 7 (the roll paper 7 of the present embodiment is generally called “coreless”). In the case of roll paper having a paper core, the paper core is supported. Further, the fixed amount feed roller 85 and the winding shaft 8
The rotation shaft 7 protrudes from the left and right sides of the main body 82, and gears 91 and 92 are fixed to the outside of the left side of the main body 82, respectively.

Further, on the side wall of the main body 82, an elongated hole 82b is formed which is substantially perpendicular to the transport path of the roll paper 7 from the outer periphery of the pin 83 to the fixed amount feeding roller 85. A pin 93a formed on the pin 93 is fitted. The press contact plate 89 includes the support portion 93 and the support portion 93.
Plate portion 95 which is swingably connected to pin 95 via pins 95a.
And a compression coil spring 97 that urges the plate portion 95 in a direction separating from the support portion 93. As shown in FIG. 5, guide pins 82c are provided on the left and right side surfaces of the main body 82.

A nip roller 98 is provided inside the lid 81.
It is provided through an oval hole 81a formed in the lid 81. When the nip roller 98 is mounted on the printer main body, the nip roller 98 receives a pressing force of a plate spring 99 provided on an upper frame of the printer main body, and is pressed against the fixed amount feeding roller 85 to sandwich the roll paper 7. Further, above the lid 81 (above in FIGS. 5 and 6), an opening 81b for projecting the roll paper 7 to the outside and an opening for detecting the amount of the roll paper 7 on the take-up shaft 87 side. 81c and the main body 82
An opening 82d for detecting the presence / absence of the roll paper 7 on the pin 83 side by a sensor 110 described later is formed below the sensor. In addition, around the opening 81b,
A notch 81d for penetrating the leaf spring 99 is also formed.

Next, FIG. 7 is a front view showing the configuration of the maintenance unit 100 when the cassette 80 is mounted, FIG. 8 is a sectional view taken along the line DD, and FIG. 9 is a left side view thereof.
In FIG. 7, the press-contact plate 89 is omitted, and in FIG. 9, the side frames 102 are drawn by imaginary lines.

As shown in FIGS. 7 and 8, the maintenance unit 100 includes a pair of side frames 102 and 103. Each side frame 102 and 103 has a pin 82c.
And guides 104 and 105 for individually guiding the winding shaft 87 (FIG. 8). Guides 104, 10
When the cassette 80 is mounted along the axis 5, the movable parts 111 and 113 of the sensor 110 disposed below the
It swings around 11a and 113a. When the cassette 80 is completely mounted, the movable unit 1 on the carriage 3 side
11 comes into contact with the roll paper 7 held by the pins 83 in the cassette 80. The configuration of the sensor 110 will be described later in detail.

The pins 93a of the press contact plates 89 projecting from both sides of the cassette 80 swing around the front end of the maintenance unit 100 (on the carriage 3 side; hereinafter, the front and rear sides are similarly defined for the cassette 80). Engaging with the tips of a pair of arms 115. Maintenance unit 100
Further, a lever 117 that swings in contact with the carriage 3 is provided further forward of the carriage 3, and the pressing plate 89 protrudes as follows according to the swing of the lever 117.

The lever 117 is connected to the maintenance unit 1
When the carriage 3 moves to the above-described maintenance area, the carriage 3 is pushed by the carriage 3 so as to be pivotable about a shaft 121 (FIG. 7) protruding forward of the position 00 and is indicated by a two-dot chain line in FIG. Rocks clockwise until Lever 11
7, a bevel gear 117a around the shaft 121 is integrally formed, and the bevel gear 117a meshes with a bevel gear 123a integrally formed on the pressing piece 123. Pressing piece 123
Are the tip of the shaft 125 projecting in parallel with the shaft 121 and the shaft 121
The lever 117 swings counterclockwise in FIG. 8 (clockwise in FIG. 9) with the swing of the lever 117. In order to clearly show the configuration of the pressing piece 123, the shaft 121 is shown in FIG. 8, and the shafts 121 and 1 are shown in FIG.
25 and the lever 117 are not shown.

The front ends of the pair of arms 115 are
The tip of the pressing piece 123 presses the iron plate 129 with the swing. As shown in FIGS. 8, 9, and 13, each arm 115 has an upper arm 131 that swings around a shaft 115a and a small-diameter portion of a key-shaped hole 131b provided substantially in the middle of the upper arm 131. Lower arm 133 that can swing around a stepped caulking pin 133b that fits
And the front end of the upper arm 131 is fixed to the left and right edges of the iron plate 129, or both are integrally formed by a single metal plate. A tension coil spring 135 is provided between the front end of the lower arm 133 and the lower end of the iron plate 129. The distal end (rear end) of the lower arm 133 is urged upward by the extension coil spring 135, and the lower end of the lower arm 133 is normally opposed to the projecting piece 131c that is bent at the lower edge of the front end of the upper arm 131. The state where the edges are in contact, that is, the upper arm 131 and the lower arm 13
3, a gap 115b is formed between the rear ends of the pin 3 such that the pin 93a just fits. Note that the tension coil spring 135 also has an action of preventing the stepped caulking pin 133b of the lower arm 133 from moving from the small-diameter portion side to the large-diameter portion side of the key-shaped hole 131b of the upper arm 131, and fits them together. maintain.

When the iron plate 129 is pressed by the pressing piece 123 as described above, the entire arm 115 is
The pressure plate 89 swings clockwise in FIG. 9 around the center 15a, and the pressing plate 89 projects together with the roll paper 7. When the pressure contact plate 89 comes into contact with the nozzle head 31 or the like with the roll paper 7 interposed therebetween, the lower arm 133 is moved to the stepped caulking pin 133b.
9 counterclockwise in FIG. 9 (clockwise in FIG. 8) against the urging force of the extension coil spring 135, so that the impact at the time of contact can be reduced. Moreover, even if each member has some error or variation in production or assembly, or even if the distance of the nozzle surface 36 from the platen is changed in accordance with the type of printing paper in order to improve the printing quality. The pressing plate 89 can be uniformly pressed against the nozzle surface 36. Further, the pressing piece 123
When no pressing force is applied, the arm 115 is held at the lowered position by the action of the leaf spring 137 (FIG. 8).

Next, a gear mechanism for driving the maintenance unit 100 will be described with reference to FIG. Gear 141 provided at the front end of maintenance unit 100
Is configured coaxially with a transport roller (not shown) for transporting the recording paper, and is rotated by receiving the driving force of the transport roller.
A gear 142 that meshes with the gear 141 is provided with a lever 142a that is bent in a dogleg shape so as to be coaxially swingable. A gear 143 meshing with the gear 142 is provided at one end of the lever 142a, and constitutes a so-called planetary gear mechanism. The other end of the lever 142a is connected to the upper arm 13
1 can be brought into contact with the contact piece 131a provided on the lower side.

The gear 141 rotates clockwise when the recording paper is transported, so that the gear 142 rotates counterclockwise and the gear 143 rotates clockwise. by this,
The lever 142a swings counterclockwise, and the gear 143
The two large and small gears do not mesh with the adjacent gear 144. FIG. 9 shows the gear 141 in this state.
143 and the movement of the lever 142a are indicated by arrows. When the lever 142a swings to the position shown in FIG. 9, it is locked by a stopper (not shown) and does not swing any further. Therefore, the driving force is not transmitted to the maintenance unit 100 while the recording paper is conveyed and the head 1 performs image formation.

When the conveying roller rotates in the reverse direction and the counterclockwise rotation is transmitted to the gear 141, the lever 142a swings clockwise. However, when the arm 115 swings downward as shown by the solid line in FIG. 9, the other end of the lever 142a comes into contact with the contact piece 131a of the upper arm 131.
The gear 143 does not mesh with the gear 144. The carriage 3 moves to the maintenance area, and moves the upper arm 131 to the position shown in FIG.
When the transport roller rotates in the reverse direction when pushed up to the position shown by the two-dot chain line, the lever 142a swings to the position shown by the two-dot chain line in FIG. 9, and the gear 143 meshes with the large diameter portion of the gear 144. That is, the driving force is transmitted to the mechanism after the gear 144 only when the carriage 3 moves to the maintenance area and the transport roller rotates in the reverse direction.

The small diameter portion of the gear 144 meshes with the gear 146 via the large diameter gear 145. The gear 146 also has a configuration in which two large and small gears are integrated.
5 meshes with the large diameter portion of the gear 146. The small-diameter portion (not shown) of the gear 146 meshes with the gear 91 exposed on the left side surface of the cassette 80 when the cassette 80 is completely mounted. The large-diameter portion of the gear 144 meshes with the gear 149 via the gears 147 and 148. As shown in FIG. 10, the gear 149 has a configuration in which two large and small gears are integrated, and the small diameter portion meshes with the large diameter gear 150. When the cassette 80 is completely mounted, the gear 150 meshes with the gear 92 of the cassette 80 (FIG. 9). For this reason, when the driving force is transmitted to the gear 144, the fixed feed roller 85 and the take-up shaft 87 of the cassette 80 integrated with the gears 91 and 92 are rotated, and the roll paper 7 can be transported.

Further, the large diameter portion of the gear 149 is
5 is engaged with a gear 157 which rotates integrally with the gear 5. As shown in FIG. 10, the groove cam 155 has an eccentric substantially annular shape.
The groove 158, 159 has
59 drives the pump 160. That is, the pump 160 includes a piston 161 that slides by engaging the pin 161 a in the groove 158, and a pin 16 in the groove 159.
And a piston 163 that slides by engaging the piston 3a. An intake port 165a and an exhaust port 165b are formed in the cylinder 165 in which the pistons 161 and 163 are fitted.

Therefore, when the groove cam 155 rotates, the pistons 161 and 163 slide in different phases, and the volume of the space formed between them increases and decreases. At this time,
Since either the intake port 165a or the exhaust port 165b is closed by the piston 161 or 163, compressed air can be sent from the exhaust port 165b to the air chamber 20 of the head 1 via the pipe 57 (FIG. 3). . Therefore, after arranging the carriage 3 in the maintenance area,
If the transport rollers are reversed, the above-described purging can be performed while transporting the roll paper 7.

Next, a sensor 11 as a roll detecting device
0 will be described with reference to FIGS. 11 and 12. FIG. As shown in FIG. 11A, the movable portion 113 is formed of an S-shaped bar having a shaft 113a as a swing fulcrum at one end, and has left and right side surfaces near the center from the tip of the movable portion 113. A long groove 113b extending to the end is formed. The movable portion 111 is configured to sandwich the movable portion 113 from both sides, and as shown in a partial cross-sectional view of FIG. 11B and FIG. 8, a protrusion 111b that engages from both sides is formed in the groove portion 113b. . For this reason, the movable part 11
When 1 or 113 swings in the direction of arrow A, the engagement position of the projection 111b with the groove 113b moves in the direction of the shaft 113a in accordance with the swing. Accordingly, the other movable part 113 or 111 also swings in the direction of the arrow A, and retracts so that the two are folded. Also, the movable part 111
Is urged in a direction opposite to the arrow A by a torsion coil spring 169 provided on the shaft 111a.

Therefore, when the cassette 80 is not present, the protrusion 111b is engaged near the tip of the groove 113b, and the movable parts 111 and 113 are connected to each other near the tip to form a mountain shape. When the cassette 80 is inserted or removed, the movable portion 113 or 111 is pressed against the lower surface of the main body 82 of the cassette 80 and swings in the direction of arrow A, and the movable portion 1
11 and 113 are retracted so as to be folded. Cassette 8
0 is completely mounted, the movable parts 111,
Reference numeral 113 protrudes into the cassette 80 from the opening 82d, and the movable portion 111 contacts the unused roll paper 7. For this reason, when the unused roll paper 7 remains sufficiently, the movable portion 111 swings relatively largely in the direction of arrow A,
As the roll paper 7 decreases, it swings in the direction opposite to the arrow A. Therefore, in the sensor 110, a lever 111c that swings integrally with the movable portion 111 about the shaft 111a is provided outside the side frame 103, and a limit switch 171 is provided near the tip of the lever 111c.

The limit switch 171 is provided at a position where the movable portion 171a is pushed and turned on when the lever 111c swings by a predetermined amount in accordance with the reduction of the roll paper 7. For this reason, when the cassette 80 is completely mounted, when the limit switch 171 is turned on, it is possible to detect that the roll paper 7 has decreased and is approaching the replacement time. The movable portion 111 corresponds to a second movable portion, and a position when the lever 111c swings by the predetermined amount corresponds to a second predetermined position. In FIG. 11A, for convenience of explanation, the limit switch 171 is slightly shifted downward.

A movable portion 173 that swings around a shaft 173a is provided above the lever 111c. The movable portion 173 is provided when the cassette 80 is completely mounted.
An engaging portion 173b is provided for engaging the pin 82c guided along the guide 104 from above. Also, the movable part 1
73 is urged downward by the extension coil spring 175,
When the protrusion 173c at the base end abuts on the stopper 177, the downward swing is locked. Furthermore, the movable part 1
A hollow part 179 is formed on the lower surface of the movable part 173.
Is moved downward as described above, the movable portion 171a is pushed by the inner wall of the hollow portion 179, and the limit switch 1 is pressed.
71 is turned ON. The movable portion 173 corresponds to a first movable portion, and a position where the protrusion 173c contacts the stopper 177 corresponds to a first predetermined position.

Therefore, when the cassette 80 is not present, the movable portion 173 swings to a position where the projection 173c contacts the stopper 177, and the limit switch 171 is turned off.
N. When the cassette 80 is inserted, the movable unit 1
Reference numeral 73 causes the slope 173d at the tip to abut against the pin 82c and is pushed up by the pin 82c. Subsequently, the cassette 80
Is completely mounted, and when the pin 82c is disposed at the tip (front end) of the guide 104, the movable portion 173 swings slightly downward to engage the engaging portion 173b with the pin 82c. In this state, the inner wall of the hollow portion 179 does not contact the movable portion 171a, and the limit switch 171 is turned off.
Further, the pin 82c is formed in a columnar shape, and the engaging portion 173b is formed.
Is formed in a concave shape along the outer peripheral surface thereof, so that when the engaging portion 173b engages with the pin 82c, the cassette 80
Can be fixed.

In the sensor 110 configured as described above,
In a state where the cassette 80 does not exist, the movable portion 173 swings downward and the lever 111c swings in the direction opposite to the arrow A, and both of them turn on the limit switch 171.
Let me. At this time, the tip of the lever 111c may overlap with the movable portion 173, but may be arranged so that they do not overlap at all. In FIG. 12, both are prevented from overlapping.

When the cassette 80 is inserted, the movable portion 113 is pushed on the lower surface of the main body 82, and the movable portion 111 and the lever 111c also swing in the direction of arrow A. However, the movable portion 173 does not swing, and the limit is kept. The switch 171 is kept on. When the cassette 80 is completely mounted, the movable portion 173 swings upward, and the inner wall of the hollow portion 179 does not press the movable portion 171a. At this time, the movable parts 111, 1
13 projects into the cassette 80 from the opening 82d,
If there is enough unused roll paper 7 in the cassette 80, the lever 111c does not press the movable portion 171a, and the limit switch 171 is turned off. Further, when the unused roll paper 7 decreases due to the use of the roll paper 7, the lever 1
11c turns on the limit switch 171.

As described above, the limit switch 171 is
It is turned off only when the cassette 80 is completely installed and the unused roll paper 7 is sufficiently present, and is turned on when any one of the conditions is missing. That is,
In the sensor 110, it is possible to determine whether or not the above two conditions necessary for executing purging are simultaneously satisfied by one limit switch 171. Therefore, in the sensor 110, the configuration for detecting the presence or absence of the roll paper 7 can be extremely simplified and downsized.
Therefore, in the present inkjet printer, the maintenance unit 100 can be downsized favorably, and a wide printing area can be secured without increasing the size of the entire apparatus. Further, the sensor 110 has a limit switch 171.
, The manufacturing cost of the ink jet printer can be reduced favorably.

Further, the roll paper 7 wound in a roll shape around the outer periphery of the pin 83 adheres well to the core. Furthermore, the movable part 1
The roll 11 swings in the core direction of the roll paper 7 as the roll paper 7 decreases. In the sensor 110, the movable portion 111
The presence or absence of the roll paper 7 is detected by the swing of
The presence or absence of cut sheets such as cut sheets can be detected with an accuracy that cannot be realized at all. Therefore, if the permission / prohibition of the reverse rotation control of the transport roller is switched or a predetermined error message is output based on the state of the limit switch 171, the maintenance operation such as purging is performed incompletely, and a good operation is performed. It is possible to extremely effectively prevent the image formation from being disabled, and to minimize the prohibition and output of the error message.

When the cassette 80 is not present or when the cassette 80 is completely mounted, the movable portions 111 and 113 are connected to each other in the vicinity of the distal end and projected in a mountain shape. Therefore, no matter which side the cassette 80 contacts, the movable portion 111 or 113 on the contacting side can be easily swung. Then, by this swing, the pair of movable parts 111 and 113 are retracted so as to be folded. Therefore, the degree of freedom in the arrangement of the movable parts 111 and 113 is increased, and the movable parts 111 and 11
3 to save space. Therefore, in the present ink jet printer, the maintenance unit 100 can be downsized more favorably, and a wide print area can be secured very favorably without increasing the size of the entire apparatus.

It should be noted that the present invention is not limited to the above embodiment at all, and can be implemented in various forms without departing from the gist of the present invention. For example, the limit switch 171 may be turned off when the movable part 171a is pressed. Further, in the above embodiment, the limit switch 171 is used as the detecting means, but various other configurations can be considered as the detecting means. For example, the lever 111c and the movable portion 173 are configured by magnets, and the limit switch 171
A Hall element as a detecting means may be provided at the position of. In this case, the fact that at least one of the lever 111c and the movable portion 173 swings and approaches can be detected by the Hall element, and the same operation and effect as those in the above-described embodiment occur. Further, the present invention can be applied to uses other than the ink jet printer as long as it detects the presence or absence of a band wound in a roll and stored in a cassette. In the above embodiment, since the roll paper 7 is coreless, detection by the sensor 110 can be performed more reliably.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a basic configuration of an ink jet printer to which the present invention has been applied.

FIG. 2 is an exploded perspective view illustrating a configuration of a head of the inkjet printer.

FIG. 3 is a top view illustrating a configuration of an ink tank of the head.

FIG. 4 is a BB line and C showing the configuration of the ink tank.
FIG. 4 is a sectional view taken along the line C.

FIG. 5 is a left side view showing a configuration of a cassette for maintenance of the head.

FIG. 6 is a longitudinal sectional view showing the configuration of the cassette.

FIG. 7 is a front view illustrating a configuration of a maintenance unit when the cassette is mounted.

FIG. 8 is a diagram showing a configuration of the maintenance unit DD.
It is a line sectional view.

FIG. 9 is a left side view illustrating the configuration of the maintenance unit.

FIG. 10 is a right side view illustrating a configuration near a pump of the maintenance unit.

FIG. 11 is a perspective view and a partial cross-sectional view illustrating a configuration of a sensor of the maintenance unit.

FIG. 12 is an explanatory diagram showing the configuration and operation of the sensor.

FIG. 13 is an exploded perspective view illustrating a configuration of an arm of the maintenance unit.

FIG. 14 is an explanatory diagram illustrating a configuration of a flow path of a nozzle head.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Head 3 ... Carriage 5 ... Guide shaft 7
... Roll paper 10 ... Ink tank 20 ... Air chamber 20b ... Through hole 31 ... Nozzle head 35 ... Outbound path 37 ... Return path 55 ... Cap 57
... pipe 70 ... control board stage 80 ... cassette 100
... Maintenance unit 110 ... Sensor 111 ... Movable part 111b ... Protrusion 111c ... Lever 113 ... Movable part 113b ... Groove part 169 ... Twisted coil spring 171 ... Limit switch 173 ... Movable part 17
3b: engaging portion 173d: slope 175: extension coil spring 179
… Hollow section

Claims (3)

[Claims] The present invention relates to a cassette which accommodates a band wound in a roll shape and which is used when the band is mounted at a predetermined mounting position. A roll detection device for detecting the presence / absence, wherein a first movable portion which moves to a first predetermined position when the cassette is not at the mounting position, and wherein the band is removed from the cassette disposed at the mounting position. A second movable portion that moves to a second predetermined position when the second movable portion moves to the second predetermined position, and the first movable portion does not move to the first predetermined position, and the second movable portion And a detecting means for detecting that the unit has not moved to the second predetermined position. 2. The detecting means is pressed by the first movable part moved to the first predetermined position and also by the second movable part moved to the second predetermined position,
2. The roll detecting device according to claim 1, further comprising a switch that outputs or stops outputting a predetermined signal when pressed by at least one of the first movable unit and the second movable unit. . 3. The ink jet printer according to claim 1, wherein the cassette is a cassette mounted on a maintenance mechanism of the ink jet printer, and the band is used for wiping a head surface of the ink jet printer. Roll detection device.