JP2000043282A - Liquid container, cartridge containing it and recorder employing cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect residual quantity regardless of the composition of liquid by an arrangement wherein the face for receiving light from an external apparatus and reflecting the received light and the face for receiving the reflected light and reflecting the received light in the direction of the external apparatus are recessed inward to touch the liquid in a container and a prism is disposed while projecting inward. SOLUTION: A translucent ink tank 7 is made of a light transmitting material, e.g. polypropylene, and a triangular cut 250 is made at the lower part of side wall, a prism 180 is disposed on the bottom face and a concave reflecting part 190 for detecting presence of the ink tank is formed on the side. A rough surface part 210 reflecting light randomly is provided between the prism 180 and the reflecting part 190. Presence of ink and the ink tan 7 is determined based on the variation in the quantity of receiving light when the prism 180 and the reflecting part 190 are located oppositely to an optical unit 14 comprising a light emitting element and a light receiving element secured to a chassis and when a carriage mounting the tank 7 is moved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid container, a cartridge including the liquid container, and a recording apparatus using the cartridge, and more particularly to a liquid for supplying ink to a recording head that performs recording in accordance with an ink jet system. The present invention relates to a storage container, a cartridge including the liquid storage container, and a recording apparatus using the cartridge.

[0002] More specifically, the present invention relates to the structure of a prism provided for detecting the remaining amount of liquid stored in a liquid storage container.

[0003]

2. Description of the Related Art In a recording apparatus using a recording head according to an ink jet system and an ink tank for supplying ink to the recording head, various methods have recently been used to detect the amount of ink used and the amount of ink remaining in the ink tank. Developed and commercialized.

Conventionally known methods for detecting the remaining amount of ink include a so-called dot count method, a remaining amount detection method using a movable portion such as a diaphragm, and a dielectric method in which an ink tank is treated as an equivalent circuit including a capacitor. .

[0005] In addition to these methods, various optical ink remaining amount detection methods using a photo sensor have been proposed. For example, a method in which a part of an ink tank is made translucent or transparent, light is emitted from a light emitting element such as an LED to the ink tank, and the amount of ink is directly measured using the transmitted light or reflected light (Japanese Patent Laid-Open No. JP-A-108543), a method in which a reflection plate is provided inside an ink tank and the amount of ink is detected from reflection of light on the reflection plate (JP-A-7-237300), a sponge as an ink absorber provided in the ink tank There is a method (JP-A-8-112907, JP-A-9-1815) for detecting the amount of reflection by utilizing the fact that the amount of light reflection changes due to a change in the amount of ink in a portion.

Further, a mechanism for detecting the remaining amount of ink using an optical prism provided on the bottom of the ink tank is disclosed in Japanese Patent Application Laid-Open Nos. 7-164626 and 9-2.
No. 26149 discloses a detailed detection mechanism. In particular, in an ink remaining amount detecting mechanism using an optical prism, it is usual that the shape of the prism portion is usually designed so that the cross-sectional shape of the surface that comes into contact with the ink and reflects light becomes flat.

[0007]

However, in the above conventional example, when the ink tank is actually manufactured, the surface of the optical prism that comes into contact with the ink is formed into a slightly concave surface due to heat shrinkage during molding of the resin. There were many. Therefore, when the ink in the ink tank is consumed and the surface of the optical prism is exposed, a small amount of ink is likely to remain on the concave surface, and even though the ink is almost completely removed from the ink tank, the remaining amount of the ink remains. In some cases, the detection result of the detection sensor indicates a state of “ink present” or a state close thereto, and information about the remaining amount of ink may not be able to be obtained accurately.

On the other hand, pigment-based inks which have come into practical use in recent ink jet recording apparatuses contain a large amount of surfactants and resins for dispersing pigments and the like, so that they adhere to resin surfaces such as inner walls of ink tanks. It has the characteristic that it is easy to adhere and naturally adheres to the optical prism surface. Therefore, when such an ink is rapidly consumed, the ink remains on the optical prism surface while being attached, and the ink remaining amount detection sensor outputs “ink” even though the ink is actually exhausted. There is a great risk of misunderstanding that there is.

Further, even when the ink is gradually used, the adhesion to the inner surface of the ink tank and the optical prism (hereinafter referred to as wettability) depends on the composition of the ink.
In some cases, the ink adhered to the surface of the optical prism and remained. In such a case,
Again, as in the case described above, the ink remaining amount detection sensor is actually in a state where the ink has run out,
There is a risk of misunderstanding that "ink is present".

To cope with such a problem, a method of applying a so-called water-repellent agent containing silicon, fluorine, or the like to the surface of the optical prism so as to prevent ink from remaining on the surface of the optical prism has been conventionally known. However, it is technically difficult to apply a water repellent to an optical prism, which is a specific portion inside the ink tank, after forming the ink tank, and this has caused an increase in ink tank manufacturing cost.

Further, due to the characteristics of the ink tank, the ink tank is stored for a long time at a store or at a user's hand in a state where a liquid such as ink is contained therein. The part melts into the ink and changes the ink composition.As a result, the wettability of the ink is changed, the accuracy of detecting the remaining amount of ink is deteriorated, and the printing operation by the print head may be adversely affected. there were.

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional example, and has a liquid container capable of stably detecting the remaining amount of a contained liquid, for example, irrespective of the composition of the ink.
It is an object to provide a cartridge including the liquid storage container and a recording device using the cartridge.

[0013]

In order to achieve the above object, a liquid container according to the present invention has the following configuration.

That is, a storage portion for storing a liquid, a first surface for receiving light incident from an external device, a light for receiving light reflected by the first surface, and an optical path of the received light, A second surface for changing an optical path toward an external device, a prism formed of a light transmissive member, and protruding toward the inside of the housing portion; A surface is a contact surface with a liquid stored in the storage unit, and the first and second surfaces are convex with respect to the inside of the storage unit. .

Here, the prism may be provided on the bottom surface of the storage section.

The optical path portion of the prism may be a gap, or may be formed of a light transmitting member. The light transmitting member is desirably made of resin.

Furthermore, the central portion of the first and second surfaces is slightly convex as a whole with respect to the inside of the housing portion, while a concave portion is formed near the convex portion. More preferably, it is formed.

The storage section includes (1) a first storage section which is a space for storing a liquid, and (2) a second storage section packed with an absorber for holding the liquid. It may be configured to have a storage section.

Furthermore, the prism may be installed on the side surface of the storage unit, or a plurality of prisms may be provided on the bottom and side surfaces of the storage unit.

The above-mentioned liquid may be ink, and the ink may be applied to the recording medium in order to improve the fixability and water resistance of the image recorded on the recording medium or to improve the quality of the image. The processing liquid to be discharged may be used.

According to still another aspect of the present invention, there is provided a cartridge including the above-described liquid storage container, wherein a recording head for discharging the liquid stored in the liquid storage container, and a holder for holding the liquid storage container. Is provided.

Here, it is desirable that the liquid container is separable from the holder.

The recording head is an ink jet recording head that performs recording by discharging ink. Further, the head generates thermal energy to be applied to the ink in order to discharge the ink by using the thermal energy. It is desirable to have a heat energy conversion body for the conversion.

According to still another aspect of the present invention, there is provided a recording apparatus for recording an image on a recording medium using the cartridge having the above-described configuration, wherein the prism irradiates light and receives reflected light from the prism. Optical means, detecting means for detecting the remaining amount of the liquid stored in the liquid storage container based on the reflected light received by the optical means, and based on a detection result obtained by the detecting means, And a control unit for controlling a recording operation by the recording head.

According to the present invention, when recording is performed using the cartridge including the liquid container having the above structure, the prism is irradiated with light, and when light reflected from the prism is received, the light is received. The remaining amount of the liquid stored in the liquid storage container is detected based on the reflected light, and the recording operation by the recording head can be controlled based on the detection result.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a schematic configuration of a recording apparatus provided with a recording head for performing recording according to an ink jet system, which is a typical embodiment of the present invention. In this embodiment, as shown in FIG. 1, the recording head 1 is connected to an ink tank 7 for supplying ink to the recording head 1 and integrally forms an ink cartridge 20. In this embodiment, the ink cartridge 20 has a configuration in which the recording head 1 and the ink tank 7 can be separated as described later, but an ink cartridge in which the recording head and the ink tank are integrated may be used. .

The bottom surface of the ink tank 7 is provided with an optical prism for detecting the remaining amount of ink and a concave light reflecting surface for detecting the presence or absence of the ink tank. This configuration will be described later in detail.

Further, the recording head is provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for discharging ink, particularly in an ink jet recording system. By using a method in which a change in the state of the ink is caused by the thermal energy, higher density and higher definition of recording are achieved.

In FIG. 1, a recording head 1 is mounted on a carriage 2 in a posture for ejecting ink downward in the figure, and ejects ink droplets while moving a carriage 2 along a guide shaft 3 to form recording paper. An image is formed on a recording medium (not shown) as described above. The carriage 2 is moved left and right (reciprocated) via the timing belt 5 by the rotation of the carriage motor 4. An engagement claw 6 is provided on the carriage 2 and engages with an engagement hole 7a of the ink tank to fix the ink tank 7 to the carriage 2.
When printing for one scan of the print head is completed, the printing operation is interrupted, the printing medium located on the platen 8 is conveyed by a predetermined amount by driving the feed motor 9, and then the carriage 2 is moved along the guide shaft 3 again. To form an image for the next one scan.

On the right side of the apparatus main body, a recovery device 1 for performing a recovery operation for keeping the ink discharge state of the recording head 1 good.
The apparatus 10 includes a cap 11 for capping the recording head 1, a wiper 12 for wiping the ink ejection surface of the recording head 1, and a device for sucking ink from the ink ejection nozzles of the recording head 1. A suction pump (not shown) and the like are provided.

The driving force of the feed motor 9 for conveying the recording medium is transmitted to the original recording medium conveying mechanism and also to the automatic paper feeder (ASF) 13.

Further, on the side of the recovery device 10, an infrared LE
An optical unit 14 for detecting the remaining amount of ink and detecting the presence / absence of an ink tank is provided. The light-emitting element 15 and the light-receiving element 16 are mounted so as to be arranged along the recording paper conveyance direction (the direction of arrow F). The optical unit 14 is attached to a chassis 17 of the apparatus main body. When the ink cartridge 20 is mounted on the carriage 2 and moves rightward from the position shown in FIG.
4 above. The state of ink and the presence or absence of an ink tank can be detected from the bottom surface of the ink tank 7 by the optical unit 14 (details will be described later). Next, a control configuration for executing the recording control of the above-described apparatus will be described.

FIG. 2 is a block diagram showing the configuration of the control circuit of the printing apparatus. In FIG. 2 showing the control circuit, 170
0 is an interface for inputting a recording signal, 1701 is M
A PU 1702 is a ROM for storing a control program executed by the MPU 1701, and a 1703 is a DRAM for storing various data (such as the print signal and print data supplied to the print head 1). A gate array (G.1704) controls supply of print data to the print head 1.
A. ), The interface 1700, the MPU 170
1. Data transfer control between the RAMs 1703 is also performed. 170
5 is a head dryer for driving the recording head 1, 170
Reference numerals 6 and 1707 denote motor drivers for driving the feed motor 9 and the carriage motor 4, respectively.

The operation of the above control configuration will be described. When a recording signal is input to the interface 1700, the gate array 17
04 and the MPU 1701 converts the recording signal into recording data for printing. Then, the motor driver 17
06 and 1707 are driven, and the head driver 1
The recording head 1 is driven according to the recording data sent to 705, and recording is performed.

Reference numeral 1710 denotes an LCD 1711 for displaying various messages relating to the printing operation and the wiping state of the printing apparatus, and LEDs of various colors for notifying the printing operation and the state of the printing apparatus.
The display unit includes a lamp 1712.

The operation of the remaining ink / ink tank detector 25 for detecting the presence or absence of ink in the ink tank 7 integrated with the recording head 1 and the presence or absence of the ink tank 7 is performed by the MPU.
1701. The details of the ink remaining amount / ink tank detection unit 25 will be described later. Next, an outline of the configuration of an ink tank to which the present invention can be suitably applied will be described with reference to FIGS.

FIG. 3 is an external perspective view of a head holder 200 provided with the ink tank 7 and the recording head 1. In this figure, (A) shows a state where the ink tank 7 is separated from the head holder 200, and (B) shows a state where the ink tank 7 is attached to the head holder 200. Also,
FIG. 4 is a side sectional view showing the internal structure of the ink tank 7.

First, the ink tank 7 in this embodiment has a substantially rectangular parallelepiped shape, and the upper wall 7U is provided with an air communication port 120 which is a hole communicating with the inside of the ink tank.

An ink supply cylinder 140 having an ink supply port is formed on the lower wall 7B of the ink tank 7 so as to protrude in a cylindrical shape. In the physical distribution process, the air communication port 120 is made of a film or the like.
Are closed by a cap as an ink supply port sealing member.

Reference numeral 160 denotes a lever member integrally formed on the outside of the ink tank 7 so as to be elastically deformable, and a locking projection is formed at an intermediate portion thereof.

Reference numeral 200 denotes a printhead-integrated head holder on which the above-described ink tank 7 is mounted. In this embodiment, for example, ink of each color of cyan (C), magenta (M), and yellow (Y) is used. Tank 7 (7C, 7M, 7
Y). At the lower part of the head holder 200, a recording head 1 for ejecting each color ink is provided integrally. At the bottom of the head holder 200, an ink presence / absence detection unit and an ink tank presence / absence detection unit, which will be described later, can detect presence / absence of ink and presence / absence of an ink tank in cooperation with the optical unit 14 and the remaining ink / ink tank detection unit 25. The windows are provided like this.

The recording head 1 has a plurality of discharge ports formed downward (hereinafter, the surface of the head on which the discharge ports are formed is referred to as a discharge port formation surface).

Then, the ink tank 7 is moved from the state shown in FIG.
40 is engaged with an ink supply cylinder receiving portion (not shown) provided on the recording head 1, and is pushed so that the ink passage cylinder of the recording head 1 enters the ink supply cylinder 140. Then, the locking projection 160A of the lever member 160 engages with a projection (not shown) formed at a predetermined position of the head holder 200, and the proper mounting state shown in FIG. 3B is obtained. The head-integrated head holder 200 with the ink tank 7 mounted thereon is further mounted, for example, on the carriage 2 of the recording apparatus as shown in FIG. In such a state, a predetermined head difference (H) is formed between the bottom of the ink tank 7 and the ejection port forming surface of the head.

Next, the internal structure of the ink tank 7 will be described with reference to FIG. The ink tank 7 in this embodiment communicates with the atmosphere through the atmosphere communication port 120 at the upper part, and communicates with the ink supply port at the lower part, and has a negative pressure generating member that accommodates the absorber 320 as a negative pressure generating member inside. A storage chamber 340 and a substantially sealed liquid storage chamber 360 for storing liquid ink are partitioned by a partition wall 380. The negative pressure generating member storage chamber 340 and the liquid storage chamber 360 are separated from each other by a partition 380 near the bottom of the ink tank 7.
The communication is made only through the communication port 400 formed in the communication port.

A plurality of ribs 420 are integrally formed on the upper wall 7U of the ink tank 7 forming the negative pressure generating member storage chamber 340 so as to protrude into the inside thereof. Abuts on the absorber 320 accommodated in the container. Thus, an air buffer chamber 440 is formed between the upper wall 7U and the upper surface of the absorber 320. Absorber 32
Numeral 0 is formed of a heat-compressed urethane foam, and is housed in a negative pressure generating member housing chamber 340 in a compressed state so as to generate a predetermined capillary force as described later. The absolute value of the pore size of the absorber 320 for generating the predetermined capillary force depends on the type of ink used, the size of the ink tank 7,
It depends on the position of the ejection port forming surface of the recording head 1 (head difference H) and the like.

In the ink supply cylinder 140 forming the ink supply port 140A, a disc-shaped or column-shaped pressure contact body 460 is disposed. The pressed body 460 is
For example, it is formed of polypropylene felt, and does not itself deform easily due to external force. In the state shown in FIG. 3A in which the press-contact body 460 is not mounted on the head holder 200, the press-contact body 460 is held in a state where the press-contact body 460 is pressed into the absorber 320 so as to locally compress the absorber 320. For this purpose, a flange is formed at the end of the ink supply cylinder 140 to be in contact with the periphery of the pressure contact body 460.

In the ink tank having such a structure, when the ink in the absorber 320 is consumed by the recording head 1, the ink is supplied from the liquid storage chamber 360 to the negative pressure generating member storage chamber 340 through the communication port 400 of the partition wall 380. It is supplied to the absorber 320. At this time, the pressure in the liquid storage chamber 360 is reduced, but air passing from the atmosphere communication section 120 through the negative pressure generating member storage chamber enters the liquid storage chamber 360 through the communication port 400 of the partition wall 380, and the inside of the liquid storage chamber 360 is reduced. Decompression is reduced. Therefore, even if ink is consumed by the recording head 1, the ink is filled in the absorber 320 according to the consumed amount, the absorber 320 holds a fixed amount of ink, and keeps the negative pressure on the recording head 1 substantially constant. Therefore, the ink supply to the recording head 1 is stabilized. Thereafter, the liquid storage chamber 36
When the ink in 0 is consumed, the ink in the absorber 320 is consumed.

Accordingly, a mechanism for detecting the remaining amount of ink is provided in the liquid storage chamber 360 of such an ink tank,
By notifying the user that the ink in 60 has been consumed and replacing the tank, the recording apparatus can be used without worrying about running out of ink.

FIG. 5 shows an ink tank 7 according to this embodiment.
FIG. 3 is a diagram showing the structure of FIG. Here, FIG. 5A is an external perspective view of the ink tank 7, FIG. 5B is a bottom view of the ink tank 7, and FIG. 5C is a cross-sectional view taken along the line AA 'of FIG. . In FIG. 5, components described as a common embodiment with reference to FIGS. 3 and 4 are denoted by the same reference numerals, and description thereof will not be repeated. Will be described only.

As shown in FIG. 5A, in this embodiment, a triangular notch 25
0 is provided. As shown in FIGS. 5B and 5C, a prism 18 is provided on the bottom surface of the ink tank 7.
0 and a concave curved surface reflection portion 190 are provided. The prism 180 is used for detecting the remaining amount of ink described later, and the concave curved surface reflecting section 190 is used for detecting the presence or absence of an ink tank described later.

The ink tank 7 is formed of a translucent light-transmitting material, for example, a material such as polypropylene, and has an optical prism formed integrally with the ink tank 7 on the bottom surface.

When the ink tank 7 is attached to the carriage 2 and reciprocates, as shown in FIG. 5 (b), the concave curved reflecting portion 190 includes the light emitting element 15 perpendicular to the carriage moving direction and the direction. It has a curvature in two directions (F direction) aligned with the light receiving element 16, and a curved surface is formed in the entire region of the concave curved surface reflecting portion 190.

The prism 180 has a general triangular prism shape. In addition, a region 210 between the prism 180 and the concave curved surface reflection portion 190 on the bottom surface of the ink tank 7 has a rough surface. Therefore, hereinafter, this region 210
Is called a rough surface portion.

As can be seen from FIG. 5C, a part of the side surface of the prism 180 is in contact with the side wall surface of the ink tank 7, and a cutout portion 250 is provided in the contact portion. I have. Due to the presence of the notch 250, when the prism 180 and the ink tank 7 are manufactured by injection molding or the like, the molding accuracy can be improved.

As can be seen from FIG. 5B, the rough surface portion 210 has an arc shape on the side in contact with the concave curved reflection portion 190. The level of the rough surface portion 210 is
0 or the same level as the surface constituting a part of the outer wall of the ink tank 7, or the prism side protrudes outward, whereby the accuracy of detecting the remaining ink amount (S
/ N ratio).

Next, the processing for detecting the presence or absence of ink in the ink tank and the processing for detecting the presence or absence of the ink tank will be described with reference to FIGS.
This will be described with reference to FIG.

FIG. 6 shows the ink tank 7 and the optical unit 14.
Relative position relationship with the light receiving element 16
FIG. 4 is a diagram showing a relationship between the received light amount and the received light amount.

FIG. 6A is a view of the ink tank 7 and the optical unit 14 in the direction of arrow F shown in FIG.
FIG. 2B is a view of the ink tank 7 viewed in a direction of an arrow T shown in FIG. FIG. 6C shows a change in the amount of light received by the light receiving element 16 according to a change in the relative positional relationship between the ink tank 7 and the optical unit 14 in the carriage movement direction.

As shown in FIGS. 6A and 6B, an optical prism 180 used to detect the presence or absence of ink is provided at the bottom of the ink tank 7. Further, on the right side of the optical prism 180, there is provided a concave curved surface reflection section 190 formed of a light transmitting member for detecting the presence or absence of an ink tank. That surface is recessed inside the ink tank. Further, between the optical prism 180 and the concave curved reflecting portion 190, the position of the bottom surface of the optical prism 180 that opposes the light emitting element 15 and the light receiving element 16 and the roughness is relatively rougher than the concave curved reflecting portion 190, A rough surface portion 210 for irregularly reflecting light is formed.

Therefore, according to the above configuration, when the optical prism 180 of the ink tank 7 is located at a position facing the optical unit 14 fixed to the chassis 17, the presence or absence of ink is detected. Reflector 190
Is located, the presence or absence of the ink tank is detected.

When the ink tank 7 is mounted on the carriage 2 and the carriage 2 is slowly moved in the vicinity of the optical unit 14, as shown in FIG.
5 also changes. Here, a solid line indicates a change when there is no ink in the ink tank 7, and a two-dot chain line indicates a change when there is ink in the ink tank 7.

According to this change, when there is no ink in the ink tank 7, the amount of received light is the maximum value (A) where the optical prism 180 is located directly above the optical unit 14 (region a in FIG. 6C). ), And the second peak value (B) is shown where the concave curved surface reflection portion 190 is located directly above the optical unit 14 (region b in FIG. 6C). Then, it shows a minimum value (C) between the optical prism 180 and the concave curved surface reflection portion 190, that is, where the rough surface portion 210 is located directly above the optical unit 14. In addition, if the position of the optical unit 14 located directly above the optical unit 14 is outside the concave curved surface reflection portion 190 (region c in FIG. 6C) due to the movement of the carriage 2, the amount of received light substantially reaches the minimum value (C). Take.

On the other hand, when there is ink in the ink tank 7, the amount of received light is
There is almost no change at the position just above the optical unit 14, but the peak value (B) is shown at the position where the concave curved surface reflection unit 190 is located directly above the optical unit 14, as in the case where there is no ink. Although not shown, when the ink tank 7 is not mounted on the carriage 2, the amount of received light is almost close to "0" and only background light as noise is provided.

The ink presence / absence detection is performed by the ink tank 7
It is needless to say that it is desirable that the difference in the amount of received light between the case where there is ink and the case where there is no ink is large as much as possible because there is a difference depending on the color of the ink contained in the ink.
On the other hand, the presence / absence detection of the ink tank is theoretically the same in the amount of received light if the same type of tank is used. In fact, since the tank of this embodiment has a simple configuration, there is little manufacturing variation, and its value hardly changes.

FIG. 7 is a block diagram showing a detailed configuration of the ink remaining amount / ink tank presence / absence detecting section 25.

In the configuration shown in FIG.
Based on the control signal from the PU 1701, the controller 32 outputs a pulse signal having a predetermined duty (DUTY) ratio (%) to the LED drive circuit 30, and the light emitting element 15 configuring the optical unit 14 according to the duty ratio.
To irradiate the bottom of the ink tank 7 with infrared light.

The infrared light is reflected by the optical prism 18 at the bottom of the ink tank 7 and returns to the light receiving element 16 constituting the optical unit 14. The light receiving element 16 as a phototransistor converts the received light into an electric signal, and outputs the electric signal to a low-pass filter (LPF) 31. The low-pass filter (LPF) 31
The high frequency noise is cut out of the electric signals input from the controller 32, and only the low frequency signal is sent to the controller 32. The controller 32 A / D converts the signal of the low-pass filter (LPF) 31 and converts the signal into a digital signal. Then, the converted value is transferred to MPU 1701.

As shown in FIG. 7 (b), the light emitting element 15 is an LED that emits infrared light 28, and the light receiving element 16 receives infrared light 29, and responds to the intensity of the received light. A phototransistor that outputs an electric signal. As shown in FIG. 1, these LEDs and phototransistors are arranged so as to be arranged in the transport direction of the recording paper.

Next, control for detecting the remaining amount of ink and the presence / absence of an ink tank in the apparatus having the above configuration will be described with reference to a flowchart shown in FIG.

First, in step S1, the MPU 170
1 drives the carriage motor 4 via a motor driver 1701 and moves the carriage 2 to an arrow CR shown in FIG.
, So that the right end of the prism 180 of the ink tank 7 is directly above the optical unit 14.

Further, in step S2, the carriage 2 is moved at a predetermined speed in the range of the area a shown in FIG.
While moving right above the optical unit 14 in the direction of arrow CR shown in FIG.
, The optical unit 14 is driven at a predetermined duty ratio, the reflected light of the infrared light emitted from the light emitting element 15 is sequentially measured as the output of the low-pass filter (LPF) 31, and the value is A / D Enter the converted digital value.
By moving the carriage 2 in this manner, if the ink tank 7 is mounted on the carriage 2, the light receiving element 16 should be able to receive the reflected light from the prism 180 at the bottom. Then, from the input digital value,
The maximum value is obtained and the value is set to "A".
03.

Next, in step S3, the ink tank 7
The carriage 2 is moved so that the right end of the concave curved surface reflection portion 190 is located directly above the optical unit 14.

In step S4, the carriage 2 is moved at a predetermined speed in the range of the area b shown in FIG.
While moving directly above the optical unit 14 in the direction of the arrow CR shown in FIG.
, The reflected light at that time is sequentially measured as an output of a low-pass filter (LPF) 31, and a digital value obtained by A / D converting the value is input. By moving the carriage 2 in this manner, if the ink tank 7 is mounted on the carriage 2, the light receiving element 16 should be able to receive the reflected light from the concave curved surface reflecting portion 190 at the bottom. Then, the maximum value is obtained from the input digital value, and the value is stored in the DRAM 1703 as "B".

Further, in step S5, the carriage 2
Is moved so that the right end of the rough surface portion 210 is directly above the optical unit 14.

Then, in step S6, the carriage 2 is moved at a predetermined speed in the range between the area b and the area a shown in FIG.
4, the reflected light of the infrared light emitted from the light emitting element 15 is sequentially measured as the output of the low-pass filter (LPF) 31 in the same manner as in step S2, and the value is subjected to A / D conversion. Enter a value. By moving the carriage 2 in this manner, if the ink tank 7 is mounted on the carriage 2, the light receiving element 16 should be able to receive the reflected light from the bottom surface 210. At this time, if the ink tank 7 is mounted on the carriage 2, the rough surface portion 210 comes directly above the optical unit 14, but the rough surface portion 210 irregularly reflects the infrared light emitted from the light emitting element 15. The amount of light received by element 16 is significantly reduced.

Then, the minimum value is obtained from the input digital value, and the value is set to “C” to make the DRAM 170
3 is stored.

Next, in step S7, the difference (BC) between the values "B" and "C" stored in steps S4 and S6 is compared with a predetermined threshold value "α". here,
If BC <α, the process proceeds to step S9, where it is determined that the ink tank 7 is not mounted on the carriage 2, and the process ends. In this case, for example, a process of turning on an LED lamp (not shown) provided in the apparatus or notifying the user that the ink tank 7 (ink cartridge 20) is not mounted is performed. You may do it. On the other hand, if BC ≧ α, it is determined that the ink tank 7 (ink cartridge 20) is mounted, and the process proceeds to step S8.

In step S8, steps S2 and S6
Is compared with the difference (A−C) between the values “A” and “C” stored in the above and another predetermined threshold value “β”. Here, (A
If −C)> β, the process proceeds to step S10, where it is determined that there is no ink in the ink tank 7, and the process ends. In this case, for example, the LED provided on the device is
A process may be performed such as turning on a lamp (not shown) (in a different color from that when the ink tank 7 is not mounted) to notify the user that the ink tank 7 has no ink. On the other hand, if (AC) ≦ β, the process proceeds to step S11, where it is determined that there is ink in the ink tank 7, and the process ends.

By the above processing, for example, when there is no ink in the ink tank 7, as shown in FIG. 6C, the light quantity of the light receiving element becomes the maximum value when the optical prism 180 is directly above, Thereafter, when the rough surface portion 210 comes directly above, the minimum value is taken, and when the concave curved surface reflection portion 190 comes right above, the maximum value is taken. On the other hand, ink tank 7
, The maximum value is obtained when the concave curved surface reflection portion 190 comes directly above.

In order to minimize the movement of the carriage 2 in the above processing, the concave curved reflecting portion 190 is irradiated with light to detect the presence or absence of the ink tank.
May be moved to irradiate the rough surface portion 210 with light, and finally, the carriage 2 may be further moved to irradiate the optical prism 180 with light to receive reflected light from each location.

Next, the ink contact surface of the optical prism 180, which is the most significant feature of this embodiment, will be described with reference to FIG.

FIG. 9 is an enlarged perspective view of the optical prism 180.

In FIG. 9, reference numerals 181 and 182 denote two inclined surfaces constituting the optical prism 180, and reference numeral 183 denotes a virtual surface orthogonal to the inclined surface 181. Therefore, when the ink tank 7 is filled with ink, the slopes 181 and 18
2 is a contact surface with the ink. In the optical prism 180 according to this embodiment, the optical path from the light emitting element 15 to the light receiving element 16 has a gap.

FIGS. 10 and 11 are cross-sectional views of the optical prism 180 parallel to the inclined surface 181 using the virtual surface 183 as a cut surface. Note that, in these drawings, arrows indicate infrared light emitted from the light emitting element 15.
Here, FIG. 10 shows a state of a slope of a conventional optical prism, while FIG. 11 shows a state of a slope of an optical prism according to this embodiment.

In FIG. 10, (A) shows an ideal case of a slope 181 designed so that a slope 181 serving as an ink contact surface is a plane so as to reflect light well. The actual state of the slope 181 that has become slightly concave due to deformation or the like is shown.

Therefore, as shown in FIG. 10B, the ink 184 remains on the slope 181 on the surface.
Conventionally, it has not been possible to accurately detect the remaining amount of ink.

On the other hand, as shown in FIGS. 11A, 11B and 11C, in the case of the optical prism according to this embodiment,
A slope 181 serving as an ink contact surface is slightly convex to the inner surface of the ink tank. In addition,
(A), (B) and (C) show various modifications of the convex slope. In FIG. 11, reference numeral 185 denotes an end of the convex slope 181.

FIG. 12 is a diagram showing the size of each part of the optical prism using the example of FIG. 11A.

In this embodiment, the optical prism 180 provided in the ink tank 7 is made of a highly transparent polypropylene resin, and the prism width (W) shown in FIG.
m, and the height (H) of the projection on the prism surface is 0.1 mm.

The following experiment was performed using the optical prism having the above-described configuration.

That is, carbon black
Is filled in an ink tank 7 equipped with an optical prism 180, stored at 50 ° C. for one month, mounted on a recording apparatus, and continued to perform a recording operation, and an optical element accompanying the consumption of the ink. The change of the prism was tracked. As a result, immediately when the ink was exhausted from the liquid storage chamber 360, "no ink" was detected. afterwards,
When the ink tank 7 was disassembled and the optical prism was closely inspected, it was confirmed that ink did not adhere to the central portion of the slope 181.

In this experiment, for comparison, an optical prism having a shape similar to that of the example of FIG. 11A and having no convex portion (ie, the height (H) of the convex portion was 0 mm) was provided. Prototype the ink tank, store the ink under the same conditions,
Thereafter, recording was performed. As a result, the recording apparatus did not detect "no ink" even though it was visually confirmed that the ink had run out. Thereafter, when the ink tank was disassembled and the prism surface was observed, it was found that ink had adhered to the center of the slope of the prism.

According to such an experiment, when the inclined surface 181 of the optical prism has a convex curved surface as shown in FIG. 11A or FIG.
But does not adhere to the center. Further, even when the slope 181 is a convex surface having a ridgeline as shown in FIG. 11B, the same effect as the curved surface shown in FIG. 11A was observed. Further, FIG.
It was more effective to form the end 185 of the slope 181 into a concave structure in which the ink easily accumulates as shown in FIG.

Therefore, according to the embodiment described above, by forming the slope of the optical prism so as to be convex with respect to the inside of the ink tank, the slope at the time of the formation becomes concave due to the deformation at the time of the formation, and the ink is deformed. When ink is exhausted from the tank and the optical prism is exposed, ink is prevented from remaining in the concave portion.

As a result, it is possible to accurately detect the remaining amount of ink that accurately reflects the remaining amount of ink in the ink tank. It should be noted that the shape of the slope of the optical prism is shown in FIG.
As shown in (B) and (C), it may be formed so that a concave portion 187 is provided in the vicinity of the convex portion 186 at the center of the slope 181. As a result, it has been experimentally confirmed that the ink quickly moves from the convex portion 186 to the concave portion 187, so that the remaining amount of the ink can be quickly and accurately detected.

[0097]

[Other Embodiments] The optical prism used in the above embodiment has an optical path portion having a gap, but in this embodiment, the entire optical prism is formed of resin, and the optical path portion is also formed of resin. A case will be described.

FIG. 14 is a view showing an optical prism entirely formed of resin. It is to be noted that, in this figure, the virtual surface 183 shown in FIG.
FIG. 11 is a cross-sectional view of the optical prism 180 viewed in parallel with FIG.

Here, FIGS. 14A and 14B show the state of the slope of the conventional optical prism, while FIG. 14C shows the state of the slope of the optical prism according to this embodiment. Further, FIG. 14A shows an inclined surface 181 serving as an ink contact surface so as to reflect light well similarly to FIG.
14B shows an ideal case of the slope 181 designed to be flat, and FIG. 14B shows an actual state of the slope 181 which is slightly concave due to deformation at the time of molding similarly to FIG. 10B. Is shown.

As described in the above-described embodiment, in the conventional example shown in FIGS.
Is a flat surface or a concave surface, the ink 184 remains in the center portion thereof. As a result, even if the ink in the ink tank 7 runs out, the state of “ink present” may still be detected.

On the other hand, in this embodiment, FIG.
Since the central portion of the inclined surface 181 is formed in a convex shape as shown in (C), the ink does not remain in the central portion, and the optical prism is completely immersed (that is, the ink is sufficiently absorbed). A certain state) and a state where the optical prism is exposed (that is, a state where there is no ink and there is no ink on the slope), so that the remaining amount of ink can be accurately detected. become.

As an actual case, FIG.
As shown in (A) and (B), even if the slope 181 is a flat surface or a concave surface, for example, due to vibration generated when the ink tank 7 reciprocates due to a recording operation or vibration due to other causes, etc. Since the remaining ink 184 is gradually removed from the slope 181, an “out of ink” state may be detected after a long period of time (for example, three hours or more). When recording is performed, the "ink present" state may be detected even though no ink remains in the ink tank.

However, when the optical prism according to this embodiment is used, the state of “no ink” is detected as soon as the ink is consumed and the optical prism is exposed (within about one minute). It becomes possible to detect the state of "ink out" while consuming the ink to be used.

According to the experiment, the effect of removing the ink from the inclined surface of the optical prism was particularly remarkable when a black pigment ink in which carbon black was dispersed in a resin was used as the ink.

That is, a conventional optical prism (the thickness (TE) of the resin portion is 4 m) as shown in FIG.
m, the resin is polypropylene), the slope 18 of the optical prism 180 even after two days have passed since the ink has run out from the liquid storage chamber 360 of the ink tank 7.
Although the ink remained in the ink tank 1, the ink was removed from the slope 181 of the optical prism within 15 minutes in the ink tank 7 having the optical prism (TW = 4 mm) having the structure shown in FIG. As a result, the state of "no ink" could be immediately detected.

As described above, the ink tank according to this embodiment can not only accurately detect the remaining amount of ink, but also can provide quick response to a change in the remaining amount of ink. Furthermore, since the configuration of the optical prism is simple and the manufacturing can use the normal molding conditions, it contributes to the manufacture of a low-cost ink tank having an ink remaining amount detecting function.

In the embodiment described above, as described with reference to FIG. 4, the ink tank including the absorber 320 and the liquid storage chamber 360 is used, but the present invention is not limited to this. For example, as shown in FIG.
An ink tank having a configuration in which the entire inside is the liquid storage chamber 360 may be used. In FIG. 15, 188
Is an ink outlet.

In the embodiment described above, as described with reference to FIG.
Although an example in which one is provided on the bottom surface of is described, the present invention is not limited to this. For example, an optical prism 180 'may be provided on the side surface of the ink tank 7 as shown in FIG. 16, or a plurality of optical prisms may be provided on the ink tank 7 as shown in FIG. . In FIG. 16, reference numeral 189 denotes an ink liquid level.

In the example shown in FIG.
a and the prism 180b can detect the degree of ink reduction, and the optical prism 180 can detect the absence of ink.

In either case of FIGS. 16 and 17, the location of the light receiving element and the light emitting element for detecting the remaining amount of ink must be changed on the recording apparatus side in accordance with the location of the optical prism. Needless to say.

In the above embodiment, the description has been made assuming that the droplets ejected from the recording head are ink, and that the liquid stored in the ink tank is ink. It is not limited. For example, an ink tank may contain a processing liquid discharged to a recording medium in order to improve the fixability and water resistance of the recorded image or to improve the image quality.

Further, since the recording apparatus described in the above embodiment is capable of high-density and high-speed recording operation, the output means of the information processing system, for example, a copying machine,
Facsimile, electronic typewriter, word processor,
Printer as output terminal, such as workstation
Alternatively, it can be used as a handy or portable printer provided in a personal computer, an optical disk device, a video device, and the like. In this case, the recording device takes a form corresponding to the functions, usage patterns, and the like unique to these devices.

Accordingly, the scope of application of the ink tank as the liquid container according to the present invention is not limited to the recording apparatus, but extends to various devices such as facsimile machines and copiers. The present invention can be applied to a system composed of a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.) or to a device composed of one device (for example, a copying machine, a facsimile device, etc.). Good.

An object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and to provide a computer (or CPU) of the system or apparatus.
And MPU) read and execute the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

Examples of a storage medium for supplying the program code include a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, and CD.
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) May perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0119]

As described above, according to the present invention, the first and second surfaces of the prism, which are the contact surfaces with the liquid, are convex with respect to the inside of the container for storing the liquid. Therefore, when the liquid is consumed and the prism is exposed, there is an effect that the liquid does not remain on the first and second surfaces.

In particular, even when the liquid has a composition that tends to adhere to the prism surface, such as a pigment-based ink, for example, depending on the shape of the first and second surfaces of the prism, There is an effect that it is difficult to remain on the surface.

Thus, for example, when recording is performed using a cartridge including a liquid storage container containing ink, the prism is irradiated with light to detect the remaining amount of liquid in the liquid storage container. The reflected light from the prism is received, and the presence or absence of the remaining amount of liquid is detected from the amount of received light. However, since the liquid does not remain on the first and second surfaces and does not affect the amount of reflected light, the liquid storage container is used. A correct remaining amount detection that accurately reflects the amount of liquid remaining in the inside can be performed.

[0122]

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a printing apparatus including a print head that performs printing according to an ink jet system, which is a typical embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a control circuit of the printing apparatus.

FIG. 3 is an external perspective view of a head holder 200 including the ink tank 7 and the recording head 1.

FIG. 4 is a side sectional view showing the internal structure of the ink tank 7.

FIG. 5 is a diagram showing a structure of an ink tank 7 according to the first embodiment.

6 is a diagram showing a relative positional relationship between the ink tank 7 and the optical unit 14, and a relationship between the relative positional relationship and the amount of light received by the light receiving element 16. FIG.

FIG. 7 is a block diagram illustrating a detailed configuration of an ink remaining amount / ink tank presence / absence detection unit 25;

FIG. 8 is a flowchart illustrating control for detecting the remaining amount of ink and the presence or absence of an ink tank.

FIG. 9 is an enlarged perspective view of the optical prism 180.

FIG. 10 shows a slope 181 using a virtual surface 183 as a cut surface.
Parallel to the optical prism 18 shaped according to the prior art
FIG.

FIG. 11 shows a slope 181 using a virtual surface 183 as a cut surface.
FIG. 3 is a cross-sectional view of the optical prism 180 viewed parallel to FIG.

12 is a diagram showing the size of each part of the optical prism using the example of FIG.

FIG. 13 is a diagram showing an example in which a concave portion 187 is provided near a convex portion 186 at the center of a slope 181 of the optical prism.

FIG. 14 is a diagram showing an optical prism entirely formed of resin.

FIG. 15 is a cross-sectional view of an ink tank having a configuration in which the entire inside is a liquid storage chamber 360.

FIG. 16 is a sectional view of an ink tank provided with an optical prism 180 ′ on a side surface.

FIG. 17 is a cross-sectional view of an ink tank provided with a plurality of optical prisms.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording head 2 Carriage 3 Guide shaft 4 Carriage motor 5 Timing belt 6 Engagement claw 7 Ink tank 8 Platen 9 Feed motor 10 Recovery device 11 Cap 12 Wiper 13 ASF 14 Optical unit 15 Light emitting element 16 Light receiving element 17 Chassis 20 Ink cartridge 30 LED drive circuit 31 Low pass filter (LPF) 32 Controller 180, 180 ', 180a, 180b Optical prism 181, 182 Slope

Claims (16)

[Claims] A container for accommodating a liquid; a first surface for receiving light incident from an external device; a light receiving member for receiving light reflected by the first surface; A second surface that changes an optical path toward an external device, a prism formed of a light transmissive member, and protruding toward the inside of the housing portion; A liquid storage container, wherein the surface is a contact surface with the liquid stored in the storage portion, and the first and second surfaces are convex with respect to the inside of the storage portion. 2. The liquid container according to claim 1, wherein the prism is provided on a bottom surface of the container. 3. The liquid container according to claim 1, wherein an optical path portion of the prism is a gap. 4. The liquid container according to claim 1, wherein an optical path portion of the prism is also formed of the light transmitting member. 5. The liquid container according to claim 1, wherein the light transmitting member is made of a resin. 6. A central part of the first and second surfaces is slightly convex as a whole with respect to the inside of the housing part,
2. The liquid container according to claim 1, wherein a concave portion is formed near the convex portion. 7. The storage section has a first storage section serving as a space for storing the liquid, and a second storage section filled with an absorber for holding the liquid. The liquid container according to claim 1, wherein: 8. The liquid container according to claim 1, wherein the prism is provided on a side surface of the container. 9. The liquid container according to claim 1, wherein a plurality of the prisms are provided on a bottom portion and a side portion of the container. 10. The liquid container according to claim 1, wherein the liquid is ink. 11. The processing liquid discharged to the recording medium in order to enhance fixability and water resistance of an image recorded on the recording medium with ink, and to enhance the quality of the image. The liquid container according to claim 1, wherein: 12. A cartridge including the liquid storage container according to claim 1, wherein: a recording head that discharges the liquid stored in the liquid storage container; and a holder that holds the liquid storage container. A cartridge comprising: 13. The cartridge according to claim 12, wherein the liquid container is separable from the holder. 14. The cartridge according to claim 12, wherein the recording head is an inkjet recording head that performs recording by discharging ink. 15. The ink jet recording head according to claim 14, further comprising a thermal energy converter for generating thermal energy to be applied to the ink in order to discharge the ink using thermal energy. A cartridge according to claim 1. 16. A recording apparatus for recording an image on a recording medium using the cartridge according to claim 12, wherein the prism irradiates light and receives reflected light from the prism. Means, detecting means for detecting the remaining amount of liquid stored in the liquid storage container based on the reflected light received by the optical means, and recording based on a detection result obtained by the detecting means. A control unit for controlling a recording operation by the head.