JP2000190531A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect the residual amt. of ink by certainly detecting that an ink holding member such as an ink tank or the like is replaced with a novel one to set timing setting a count value for detecting the residual amt. of the ink of the ink holding member. SOLUTION: A pawl part 15C is provided on a head cartridge 15 having a recording head 15A and an ink tank 15B integrally connected thereto arid a cartridge sensor 14 is provided at the position opposed to the pawl part 15C and, when the head cartride 15 is a novel one, the cartridge sensor 14 performs switching operation by the contact with the pawl part 15C to break the pawl part 15C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having replaceable ink holding members such as ink tanks.

[0002]

2. Description of the Related Art Conventionally, as a method of detecting that the remaining amount of ink held by an ink holding member such as an ink tank of an image forming apparatus has run out (ink end), Japanese Patent Application Laid-Open No. 08-224891 is disclosed. Is known as a "dot counting method". In this method, the amount of ink ejected from the print head and the amount of ink consumed for the ejection recovery operation are measured by counting the number of times of ink ejection from the print head and the number of suction recovery operations. The remaining amount of ink is detected from the value.

This method has an advantage that a special device for detecting the remaining amount of ink is not required and the cost can be minimized. If the remaining amount of ink is not detected as a result of the detection of the remaining amount of ink using this method, the user is notified, and a series of processing called a recording head cartridge replacement sequence (for example, serial In a scan-type image forming apparatus, processing such as moving a carriage holding a printhead to a printhead replacement position, returning the carriage to the home position from the replacement position, and performing suction recovery operation of the printhead is performed. Is going. At the same time, the dot count is reset to accurately detect the remaining amount of ink.

[0004]

However, in the above-mentioned prior art, when an ink jet cartridge having a recording head and an ink tank integrally provided is used, it is necessary to detect that the cartridge has been replaced with a new one.
A circuit is provided for changing the current value when the cartridge is removed from the carriage. However, even if the same cartridge is mounted after the cartridge is removed from the carriage, the current value of the circuit changes. Therefore, in such a case, there is a possibility that the cartridge may be erroneously detected as being replaced with a new one, and the cartridge replacement sequence may be executed.

Further, in the case where the recording head and the ink tank are separated type cartridges, the replacement of the ink tank alone does not change the current value of the circuit. Therefore, the replacement of the tank is detected by an instruction from the user. . For this reason, when the user gives an erroneous instruction (for example, an erroneous instruction by opening the cover or pressing the head exchange key), there is a possibility that the cartridge exchange sequence may be executed even if the recording head and the ink tank are not exchanged. there were.

As described above, when the cartridge replacement sequence is executed even though the cartridge is not actually replaced, the dot count is reset. Therefore, the remaining ink amount obtained from the dot count does not match the actual remaining ink amount. Even if the ink actually runs out, the remaining ink amount detection does not detect “no ink”. There is a problem that ink is not discharged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to reliably detect that an ink holding member such as an ink tank has been replaced with a new one,
An object of the present invention is to provide an image forming apparatus capable of accurately detecting a remaining amount of ink by setting a timing for resetting a count value for detecting a remaining amount of ink in an ink holding member.

[0008]

An image forming apparatus according to the present invention includes an ink holding member for accommodating and holding ink, which is replaceable, and forms an image using a recording head to which ink is supplied from the ink holding member. An image forming apparatus that counts the amount of ink ejected from the recording head in order to detect a remaining amount of ink in the ink holding member; a mark applying unit that can apply a mark to the ink holding member; Mark detecting means for detecting a mark provided on the holding member, and when the mark detecting means detects that the mark is not provided on the ink holding member after replacement, the value of the count is determined. The mark is provided by the mark providing means on the ink holding member after being cleared and replaced.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram of a control system of the image forming apparatus according to the present invention. In FIG. 1, reference numeral 10 denotes a CPU for controlling the entire apparatus, 11 denotes a ROM in which a program for operating the CPU 10 is stored, and 12 denotes a RAM used by the program. Reference numeral 13 denotes a battery-backed NV for storing a dot count value and the like described later.
RAM. Reference numeral 15 denotes a head cartridge in which a recording head and an ink tank are integrated, 14 denotes a cartridge sensor for detecting a mark described later on the head cartridge 15, and 16 denotes a head cartridge and a CPU.
An I / F circuit for connecting to a bus. Reference numeral 17 denotes a drive system for moving a mechanism such as a carriage or a roller (not shown);
Is a drive system I / F circuit for connecting the drive system 17 to the CPU bus. Reference numeral 19 denotes a host computer for transmitting image data, and reference numeral 20 denotes a communication I / F circuit for connecting the host computer 19 to a CPU bus.

Reference numeral 21 denotes a panel operation unit including LEDs, a buzzer, and key switches (not shown). Reference numeral 22 denotes a panel I / O for connecting the panel operation unit 21 to a CPU bus.
This is an F circuit. 23, a reception buffer for storing data sent from the host computer 19;
Is a recording buffer in which data to be recorded using the head cartridge 15 is stored.

Next, the recording operation will be briefly described.

The data sent from the host computer 19 is stored in the reception buffer 23 via the communication I / F 20. The CPU 10 analyzes the data in the reception buffer 23, interprets the command, and transfers the image data to the recording buffer 24. When the print image is completed for one scan, the CPU 10 instructs the head cartridge 15 via the head I / F 16 to record a print or the like, and controls the drive system 17 to scan the carriage. .

As described above, the head cartridge 15 is used for each scan in accordance with the data in the recording buffer 24.
Ink is ejected from the recording head to perform recording such as printing on a recording medium such as recording paper. At that time, the head cartridge 1
The number of ink droplets ejected from the print head No. 5 (hereinafter referred to as “dot number”) is counted, and the counted values are sequentially added and stored in the NVRAM 13.

FIG. 2 is a schematic perspective view of the image forming apparatus according to the present invention.

The carriage HC has a pin (not shown) that engages with the spiral groove 5004 of the lead screw 5005, and is reciprocated in the directions of arrows a and b with the rotation of the lead screw 5005. You. The lead screw 5005 is rotated via driving force transmission gears 5011 and 5009 interlocked with forward and reverse rotation of the driving motor 5013. The head cartridge 15 is mounted on the carriage HC. The connection between the recording head and the apparatus main body is made by the head I / F 16 in FIG. 5002 is paper,
OHP films and other recording media (hereinafter simply “paper”
A press plate (paper press plate) for P, and presses the paper P against the platen 5000 in the carriage HC moving direction.

Reference numerals 5007 and 5008 denote photocouplers, and the lever 5006 of the carriage HC at that position.
A home position detecting means for detecting the presence of the motor 5013 and switching the rotation direction of the motor 5013, for example. 5
Reference numeral 016 denotes a member that supports a cap member 5022 that caps the entire surface of the recording head, and 5015 denotes a suction unit that suctions the inside of the cap member 5022, and recovers the suction of the recording head through an opening 5023 in the cap member 5022. Do. 5017 is a cleaning blade, 501
Reference numeral 9 denotes a member that enables the blade 5017 to move in the front-rear direction, and these members are supported by a main body support plate 5018. Reference numeral 5012 denotes a lever for starting suction for recovery from suction, and a cam 5 which engages with the carriage HC.
It moves with the movement of 020.

When these capping, cleaning, suction recovery, and carriage HC are positioned in the area on the home position HP side, the lead screw 5005
Is configured to perform desired processing at those corresponding positions. A mechanism for scanning the carriage HC and transporting the paper P together with these processes constitutes a drive system 17 in FIG.

Next, the details of the head cartridge replacement sequence will be described with reference to FIGS.

FIG. 3 is a flowchart for explaining a cartridge replacement sequence. FIG. 4 is an explanatory diagram of the detection of a mark, described later, on an ink tank 15B as an ink holding member in the head cartridge 15, and the operation of attaching a mark on the ink tank 15.

First, the remaining amount of ink is detected at a predetermined timing, and when the dot count value stored in the MVRAM 13 exceeds the specified amount, information indicating "no ink", that is, information indicating that there is no remaining amount of ink is displayed on the panel. The information is transmitted to the panel 21 through the I / F 22. The panel 21 has an L (not shown).
The user is notified of "no ink" by using an ED or a buzzer (step S20). Next, the "no ink"
The user who has received the notification opens the cover (not shown) to replace the head cartridge 15 (step S21) and presses a replacement key (not shown) on the panel 21 to instruct the start of the replacement of the head cartridge. (Step S22). At this time, instead of pressing the replacement key, the start of the head cartridge replacement may be instructed simply by opening the cover.

Upon receiving a cartridge replacement start instruction from the user, the CPU 10 controls the drive system 17 so that the carriage HC mounting the head cartridge 15 can be replaced by a position called a replacement position, that is, the user can replace the head cartridge 15. (Step S23). This is to prevent the user from inadvertently removing the head cartridge 15, and only in the replacement position.
5 can be removed and attached. If the head cartridge 15 is located at a position other than the replacement position,
If the ink cartridge 15 can be replaced, the ink cartridge 15 can be removed or attached after determining the presence or absence of a mark on the ink tank 15B as an ink holding member, as described later. You will be wrong. Therefore, at a position other than the replacement position, that is, at a position where the user cannot carelessly operate, by judging the presence or absence of a mark described later on the ink tank 15 as the ink holding member, accurate mark detection becomes possible. .

Next, after the carriage HC moves to the replacement position, the user replaces the head cartridge 15 (step S24). By the way, in order to detect that the head cartridge 15 has been replaced from the carriage HC, a circuit whose current value changes when the cartridge 15 is removed (hereinafter referred to as a “cartridge detection circuit”)
Is provided). Therefore, this circuit can detect whether or not the head cartridge 15 remains detached.

After the exchange of the head cartridge 15 is completed, the user presses the exchange key on the panel 21 again to instruct the CPU 10 to end the cartridge exchange (step S25). At this time, instead of pressing the exchange key, the cover may be closed to instruct the end of the cartridge exchange.

After receiving an exchange end instruction from the user through the panel I / F 21, the CPU 10 moves the carriage HC to the home position HP as shown in FIG. 4 (step S26). Then, a change in the current value of the cartridge detection circuit described above is checked to determine whether or not the head cartridge 15 is attached (step S27). If the head cartridge 15 is not attached, the process proceeds to step S31 described below.

Next, when it is determined in step S27 that the head cartridge 15 is mounted, it is determined whether or not the head cartridge 15 is an unused new one (step S28). At the time of the determination, it is detected whether or not the portion of the claw 15C on the ink tank 15B of the head cartridge 15 is broken. That is, if the claw 15C is used as a mark, and if the claw 15C is not broken, it is determined that the head cartridge 15 is an unmarked new head cartridge 15, and the process proceeds to step S29. On the other hand, if the pawl 15C is broken, it is determined that the cartridge is an old head cartridge 15 with a mark, and the process proceeds to step S31.

By the way, it is determined whether the pawl 15C on the head cartridge 15 is broken or not, as shown in FIG.
Detection is performed using the cartridge sensor 14 as shown in FIGS. This sensor 14 has fixed contacts 14A,
It is a normally open switch of a projection type having a movable contact 14C and a movable contact 14C, and is attached to the side wall of the housing of the image forming apparatus facing the pawl 15C. If the pawl 15C of the head cartridge 15 is not broken, as shown in FIG.
The carriage HC moves from the direction of arrow a to the home position HP.
On the way back to, the contacts 14A, 14B, 14 come into contact and the sensor 14 is turned on. The CPU 10 controls the sensor 14
Is ON, it can be determined that the pawl 15C is not broken. Further, as shown in FIG. 4C, the pawl 15C on the head cartridge 15 is formed by the leftward projection in the drawing of the cartridge sensor 14 using the force of the carriage HC returning to the home position HP from the direction of arrow a.
Fold.

As described above, if the sensor 14 is turned on when the carriage HC is moved to the home position HP after the replacement of the cartridge 15, it is determined that a new cartridge 15 whose pawl 15C is not broken has been replaced. Then, fold the claw 15C. On the other hand, nail 15C
If the old cartridge 15 is folded on the carriage HC, the sensor 14 does not turn on even if the carriage HC is moved to the home position HP.

Next, the CPU 10 controls the drive system 17 to recover the suction of the head cartridge 15 (step S29), and resets the dot count held in the NVRAM 13 (step S30). Next, cover closing (step S31) and capping for protecting the recording head 15A are performed (step S32).
The cartridge replacement sequence ends. If the cover is not closed after a predetermined time, only the capping is performed and the process is terminated.

As described above, in an image forming apparatus in which the remaining ink amount is detected using the dot count method,
After folding the pawl 15C of the cartridge 15, NVRA
By resetting the dot count held in M13, the remaining ink amount can be accurately detected. That is, conventionally, as described above, when replacing the cartridge,
Although the dot count was unconditionally reset, in the present invention, unless the cartridge 15 is replaced with a new one, the previous dot count value is held in the NVRAM 13 so that the count value and the actual It matches the ink level.

As described above, in the case of the present embodiment, the cartridge sensor 14 detects whether or not the pawl 15C is provided in the cartridge 15, and further has the function of folding the pawl 15C, thereby reducing the number of parts. Therefore, the apparatus is simplified and the price is reduced. In addition, cartridge 1
By folding the pawl 15C on the user 5, the user can use the unused cartridge 15 and the used cartridge 15
Can be easily determined.

In this embodiment, the pawl 15C provided on the cartridge 15 is folded as a means for marking the ink tank 15B as an ink holding member. Can be. For example, a color may be applied to an ink tank as an ink holding member by a stamp, and the color may be detected as a mark by a photo sensor or the like.

In this embodiment, the recording head 15A
And ink tank 15B integrated head cartridge 1
5, the recording head and the ink tank may be separated. In that case, by marking the ink tank, it can be similarly determined whether or not the ink tank is new.

(Others) It should be noted that the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for performing ink ejection, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and giving a rapid temperature rise exceeding the nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As this pulse-shaped drive signal, those described in U.S. Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination configuration (a linear liquid flow path or a right-angled liquid flow path) of a discharge port, a liquid path, and an electrothermal converter as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body or an electric connection with the apparatus main body or ink from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

Further, it is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, and the like as the configuration of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

The type and number of recording heads to be mounted are not limited to those provided only for one color ink, for example, and for a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full color by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent the temperature rise due to thermal energy by using the energy of the state change from the solid state of the ink to the liquid state, or to prevent the ink from evaporating, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start to solidify when reaching the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, embodiments of the present invention include a copying machine combined with a reader or the like, in addition to a device used as an image output terminal of an information processing device such as a computer.
Further, a facsimile apparatus having a transmission / reception function may be used.

[0043]

As described above, the image forming apparatus of the present invention reliably detects that an ink holding member such as an ink tank has been replaced with a new one, and detects the remaining amount of ink in the ink holding member. Since the timing for resetting the count value for printing is set, the remaining ink amount can be accurately detected.

By providing a mark on the ink holding member, the used ink holding member and the unused ink holding member can be easily distinguished.

Further, erroneous detection of replacement of the ink holding member is eliminated, so that the replacement sequence at the time of replacement of the ink holding member is not wastefully executed, and wasteful consumption of ink and recovery processing time of the recording head are wasted. Can be eliminated.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control system of an image forming apparatus according to the present invention.

FIG. 2 is a schematic perspective view of an image forming apparatus according to the present invention.

FIG. 3 is a flowchart illustrating a cartridge replacement sequence in the image forming apparatus of the present invention.

FIGS. 4A, 4B, and 4C are explanatory diagrams of a method for detecting a mark on an ink holding member in the image forming apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 CPU 11 ROM 12 RAM 13 NVRAM 14 Cartridge sensor 15 Head cartridge 15A Recording head 15B Ink tank (ink holding member) 15C Pawl part 16 Head I / F 17 Drive system 18 Drive system I / F

Claims (11)

[Claims] An ink holding member for accommodating and holding ink is exchangeably provided, an image is formed using a recording head to which ink is supplied from the ink holding member, and a remaining amount of ink in the ink holding member is detected. An image forming apparatus for counting the amount of ink ejected from the recording head, a mark providing unit capable of providing a mark on the ink holding member, and a mark detection detecting a mark provided on the ink holding member. Means, when the mark detection means detects that the mark is not attached to the ink holding member after replacement, clears the count value, and An image forming apparatus, wherein the mark is provided by the mark providing means. 2. The count value is held when the mark detection unit detects that the mark has been applied to the ink holding member after replacement. Image forming apparatus. 3. The image forming apparatus according to claim 1, wherein the mark applying unit applies the mark by changing a shape of the ink holding member. 4. The image forming apparatus according to claim 3, wherein the mark applying unit applies the mark by folding a claw provided on the ink holding member. 5. A moving means for relatively moving the ink holding member and the recording head and a recording medium, wherein the mark applying means moves the ink after the ink holding member moves to a predetermined replacement position. The mark can be applied to a holding member.
The image forming apparatus according to any one of the above. 6. A printing apparatus comprising: a moving unit configured to relatively move the ink holding member and the recording head with respect to a recording medium; A switch that, after a switch operation by a first contact with the member, deforms the ink holding member and does not contact the deformed ink holding member; and the switch provides the mark applying means and the mark. The image forming apparatus according to claim 1, wherein the image forming apparatus comprises a detecting unit. 7. The image forming apparatus according to claim 6, wherein the switch folds a claw provided on the ink holding member. 8. The image forming apparatus according to claim 1, wherein the count value includes a discharge amount of ink not contributing to printing of an image discharged from the print head. 9. The image forming apparatus according to claim 1, wherein the ink holding member constitutes a head cartridge detachably coupled to the recording head. 10. The ink holding member constitutes a head cartridge integrated with the recording head, the mark applying means is capable of applying a mark to the head cartridge, and the mark detecting means is 9. The image forming apparatus according to claim 1, wherein a mark provided on the head cartridge is detected. 11. The image forming apparatus according to claim 1, wherein the recording head has an electrothermal transducer that generates thermal energy used for discharging ink.