JP2001146023A - Liquid container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink cartridge capable of certainly detecting the residual amount of ink without requiring a complicated seal structure caused by the attachment of a detection electrode and capable of continuously detecting the consumption amount of ink. SOLUTION: An actuator is provided to the ink cartridge mounted on an ink jet recording apparatus having a recording head ejecting ink drops to supply the liquid in a container to the recording head. The ink cartirdge has the piezoelectric device attached to a liquid container having a liquid housing container and a liquid supply port to continuously detect the consumption state of a liquid. The piezoelectric device is the long member arranged to the container to extend in the direction vertical to the surface of the liquid in the container and can detect the consumption amount of the ink in the ink cartridge continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of detecting a change in resonance frequency by detecting a change in acoustic impedance, and more particularly, to a method for detecting a change in resonance frequency. More specifically, the present invention relates to a liquid container provided with a piezoelectric device for detecting the state of consumption of liquid, and more specifically, discharges ink droplets from nozzle openings by pressurizing ink in a pressure generating chamber with pressure generating means in accordance with print data. The present invention relates to a piezoelectric device provided in an ink cartridge applied to an ink jet recording apparatus for performing printing by detecting the consumption state of ink in the ink cartridge.

[0002]

2. Description of the Related Art An ink jet recording apparatus has a carriage equipped with an ink jet recording head having pressure generating means for pressurizing a pressure generating chamber and a nozzle opening for discharging the pressurized ink from the nozzle opening as ink droplets. The ink jet recording apparatus is configured to be able to continue printing while supplying ink from an ink tank to a recording head via a flow path. The ink tank is configured as a detachable cartridge so that the user can easily replace the ink tank when the ink is consumed.

Conventionally, as a method of managing ink consumption of an ink cartridge, a method of integrating the number of ink droplets ejected from a recording head and the amount of ink sucked by maintenance by software to manage ink consumption by calculation,
There is a method of managing the point in time when a predetermined amount of ink is actually consumed by attaching an electrode for liquid level detection to the ink cartridge.

[0004]

However, the method of integrating the number of ink droplets ejected and the amount of ink by software and managing the ink consumption in the calculation by software causes an error due to the printing form on the user side, etc. There is a problem that a large error occurs when the same cartridge is remounted. Also, depending on the use environment, for example, the room temperature is extremely high or low,
Another problem is that the pressure inside the ink cartridge and the viscosity of the ink change due to the elapsed time after opening the ink cartridge, etc., causing a non-negligible error between the calculated ink consumption and the actual consumption. there were.

On the other hand, in the method of managing the time when ink is consumed by the electrode, the liquid level of the ink can be actually detected, so that the presence or absence of the ink can be managed with high reliability (Japanese Patent Laid-Open No. 8-34123). Gazette). However, since the detection of the liquid level of the ink depends on the conductivity of the ink, there are problems that the types of detectable ink are limited and the sealing structure of the electrodes is complicated. In addition, since a noble metal having high conductivity and high corrosion resistance is usually used as a material of the electrode, there is a problem that the manufacturing cost of the ink cartridge is increased. Furthermore, since two electrodes need to be mounted, there is a problem that the number of manufacturing steps is increased and the manufacturing cost is increased as a result.

Accordingly, an object of the present invention is to provide a liquid container which can accurately detect the remaining amount of liquid and does not require a complicated sealing structure.

Further, the present invention provides a liquid container which requires a small number of liquid container manufacturing steps, has a low manufacturing cost, and can continuously detect the amount of liquid consumed in the liquid container regardless of the type of liquid. The purpose is to:

[0008] This object is achieved by a combination of features described in the independent claims. The dependent claims define further advantageous embodiments of the present invention.

[0009]

According to a first embodiment of the liquid container according to the present invention, the liquid container is fixed to the container, a liquid supply port for supplying the liquid, and a liquid supply port. And a piezoelectric device having a vibrating plate having at least one end fixed to the base so as to be able to vibrate and continuously detecting a consumption state of the liquid in the container.
Preferably, the piezoelectric device is an elongated member provided in the container and extending in a direction perpendicular to the level of the liquid in the container.

[0010] Preferably, a vibration area of the vibration plate for detecting liquid extends in a direction in which a liquid level in the container changes.

Preferably, one end of the vibrating region extends to a bottom surface of the inner wall of the container below the liquid level. The other end of the vibration region extends to an upper surface of the inner wall of the container that is above the liquid surface of the liquid. The vibration region has a length of at least half of the length from the upper surface above the liquid level of the inner wall of the container to the bottom surface below the liquid level of the inner wall of the container. Having.

[0012] The piezoelectric device or the vibration region may be inclined with respect to the liquid level of the liquid in the container. The container may have an inclined surface inclined with respect to the liquid surface of the liquid in the container, and the piezoelectric device may be arranged on the inclined surface to be inclined with respect to the liquid surface of the liquid in the container.

[0013] The liquid supply port has an opening surface which opens in the direction of the inside of the container. Even when one end of the vibration area is located at the level of the liquid surface when the liquid surface of the liquid reaches the opening surface. Good.

[0014] The piezoelectric device may be provided on the inner wall surface of a hollow cylindrical liquid supply port. The piezoelectric device may extend from the inner end of the container at the liquid supply port to the outer end of the container. The piezoelectric device may be provided on an outer wall surface of a hollow cylindrical liquid supply port.

[0015] The piezoelectric device may be formed so as to have a cavity that opens toward the inside of the container and contacts the liquid in the container. The piezoelectric device may further include a vibrating portion that vibrates together with the vibrating plate, and may be formed such that one end and the other end of the vibrating portion are fixed to the base. The piezoelectric device may be formed so that the liquid comes into contact only with the vibration area of the vibration plate that detects the liquid.

Preferably, the piezoelectric device has a vibrating portion that generates vibration, and after the vibration is generated, generates a back electromotive force by residual vibration remaining in the vibrating portion, and changes a consumption state based on the back electromotive force. To detect.

The piezoelectric device may be formed so as to detect at least the acoustic impedance of the liquid and detect the consumption state of the liquid based on the acoustic impedance.

[0018] More preferably, the piezoelectric device further includes a substrate integrally provided with a storage means capable of storing information on a consumption state of the liquid detected by the piezoelectric device.

Preferably, the liquid container is mounted on an ink jet recording apparatus having a recording head for discharging ink droplets, and supplies the liquid in the container to the recording head.

According to a first embodiment of the mounting module according to the present invention, the mounting module is mounted on a liquid container having a container for containing a liquid and a liquid supply port for supplying the liquid. A piezoelectric device for continuously detecting a liquid consumption state is provided.

The mounting module is disposed in the container, and is preferably an elongated member in which the piezoelectric device extends in a direction perpendicular to the level of the liquid in the container. Preferably, one end of the piezoelectric device extends to a bottom surface of the inner wall of the container, which is below the liquid surface of the liquid. Preferably, the other end of the piezoelectric device extends to an upper surface of the inner wall of the container, which is above the liquid surface of the liquid. More preferably, the piezoelectric device has a length from an upper surface of the inner wall of the container, which is above the liquid surface of the liquid, to a bottom surface of the inner wall of the container, which is below the liquid surface of the liquid. Has a length of more than half.

Preferably, the piezoelectric device is inclined with respect to the liquid level of the liquid in the container. When the container has an inclined surface inclined with respect to the liquid level of the liquid in the container, and the mounting module body is disposed on the inclined surface, the piezoelectric device is inclined with respect to the liquid level of the liquid in the container. You may.

The liquid supply port may have an opening surface, and one end of the piezoelectric device may be located on a water level of the liquid surface when the liquid surface reaches the opening surface.

[0024] The piezoelectric device of the mounting module may be provided on the inner wall surface of the hollow cylindrical liquid supply port and extend from the inner end of the container to the outer end of the container. The mounting module may be provided on an outer wall surface of a hollow cylindrical liquid supply port.

Preferably, the piezoelectric device has a vibrating portion that generates vibration, and after the vibration is generated, a back electromotive force is generated by residual vibration remaining in the vibrating portion, and the consumption state is reduced based on the back electromotive force. To detect.

[0026] The mounting module may further include a substrate on which the storage device capable of storing information on the consumption state of the liquid detected by the piezoelectric device and the piezoelectric device are integrally provided.

Preferably, the mounting module is attached to a liquid container which is mounted on an ink jet recording apparatus having a recording head for discharging ink droplets and supplies liquid to the recording head.

That is, according to the first mode of the liquid container of the present invention, the liquid container is not described in the summary of the present invention in all of the necessary features of the present invention. Sub-combinations can also be inventions.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail through embodiments of the present invention. The following embodiments do not limit the claimed invention, and not all combinations of features described in the embodiments are necessarily essential for solving the invention.

The basic concept of the present invention is to utilize the vibration phenomenon to determine the state of the liquid in the liquid container (the presence or absence of the liquid in the liquid container, the amount of the liquid, the liquid level of the liquid, the type of the liquid, and the composition of the liquid). ). There are several methods for detecting the state of the liquid in the liquid container using a specific vibration phenomenon. For example, the elastic wave generating means generates an elastic wave to the inside of the liquid container and receives a reflected wave reflected by the liquid surface or an opposing wall to detect a medium in the liquid container and a change in its state. There is a way. Alternatively, there is a method of detecting a change in acoustic impedance from the vibration characteristics of a vibrating object. As a method of utilizing the change in acoustic impedance, a vibrating portion of a piezoelectric device or an actuator having a piezoelectric element is vibrated, and then a back electromotive force generated by residual vibration remaining in the vibrating portion is measured, thereby obtaining a resonance frequency or a reverse frequency. A method of detecting a change in acoustic impedance by detecting the amplitude of an electromotive force waveform, or measuring the impedance or admittance characteristics of a liquid when vibration is applied to the liquid, using a measuring instrument, for example, an impedance analyzer, to measure current or voltage values. There is a method of measuring the change of the current value or the voltage value when the vibration is applied to the liquid. The details of the operation principle of the elastic wave generating means and the piezoelectric device or the actuator will be described later.

FIG. 1 is a sectional view of an embodiment of an ink cartridge for a single color, for example, black ink to which the present invention is applied. The ink cartridge of FIG. 1 is based on the method of receiving the reflected wave of the elastic wave and detecting the position of the liquid surface in the liquid container and the presence or absence of the liquid, among the methods described above. Elastic wave generating means 3 is used as means for generating and receiving elastic waves. An ink supply port 2 that is connected to an ink supply needle of a recording apparatus is provided in a container 1 that stores ink. Elastic wave generating means 3 is attached to the outside of the bottom surface 1a of the container 1 so that elastic waves can be transmitted to the ink inside via the container. At the stage when the ink K is almost consumed, that is, when the ink is near the end,
The elastic wave generating means 3 is provided at a position slightly higher than the ink supply port 2 in order to change the transmission of the elastic wave from ink to gas. The receiving means may be separately provided, and the elastic wave generating means 3 may be used simply as the generating means.

The ink supply port 2 has a packing 4 and a valve body 6.
Is provided. As shown in FIG. 3, the packing 4 is engaged with the ink supply needle 32 communicating with the recording head 31 in a liquid-tight manner. The valve body 6 is always in elastic contact with the packing 4 by the spring 5. When the ink supply needle 32 is inserted,
The valve 6 is pushed by the ink supply needle 32 to open the ink flow path, and the ink in the container 1 is supplied to the recording head 31 via the ink supply port 2 and the ink supply needle 32. Container 1
On the upper wall, a semiconductor storage means 7 which stores information on the ink in the ink cartridge is mounted.

FIG. 2 is a perspective view showing one embodiment of an ink cartridge containing a plurality of types of ink, as viewed from the back side. The container 8 is divided into three ink chambers 9, 10 and 11 by partition walls. Ink supply ports 12, 13 and 14 are formed in each ink chamber. On the bottom surface 8a of each of the ink chambers 9, 10 and 11, elastic wave generating means 15, 16 and 17 are attached via a container 8 so that elastic waves can be transmitted to the ink contained in each ink chamber. ing.

FIG. 3 is a sectional view showing an embodiment of a main part of an ink jet recording apparatus suitable for the ink cartridge shown in FIGS. The carriage 30 that can reciprocate in the width direction of the recording paper has a sub-tank unit 33, and the recording head 31 is provided on the bottom surface of the sub-tank unit 33. The ink supply needle 32 is provided on the ink cartridge mounting surface side of the sub tank unit 33.

As shown in FIGS. 1 to 3, preferably, the elastic wave generating means 3 is provided on the bottom of the outer wall of the ink cartridge below the liquid level of the ink. Thereby, the elastic wave generating means 3 easily receives the reflected wave reflected from the liquid surface. Therefore, it becomes easy for the elastic wave generating means 3 to detect the liquid level where the ink gradually descends toward the bottom surface due to the consumption of the ink in the ink cartridge.

FIG. 4 is a sectional view showing details of the sub tank unit 33. As shown in FIG. The sub-tank unit 33 includes an ink supply needle 32, an ink chamber 34, a membrane valve 36, and a filter 3.
Seven. The ink supplied from the ink cartridge via the ink supply needle 32 is stored in the ink chamber 34. The membrane valve 36 is connected to the ink chamber 34 and the ink supply path 35.
It is designed to open and close by the pressure difference between The ink supply path 35 communicates with the recording head 31 and has a structure in which ink is supplied to the recording head 31.

As shown in FIG. 3, when the ink supply port 2 of the container 1 is inserted into the ink supply needle 32 of the sub-tank unit 33, the valve body 6 retreats against the spring 5, and an ink flow path is formed. The ink in the container 1 flows into the ink chamber 34. At the stage when the ink is filled in the ink chamber 34, a negative pressure is applied to the nozzle opening of the
After the ink is filled in 1, the recording operation is performed.

When the ink is consumed in the recording head 31 by the recording operation, the pressure on the downstream side of the membrane valve 36 decreases, so that the membrane valve 36 is separated from the valve body 38 and opened as shown in FIG. . When the membrane valve 36 is opened, the ink in the ink storage chamber 34 flows into the recording head 31 via the ink supply path 35. As the ink flows into the recording head 31, the ink in the container 1 flows into the sub tank unit 33 via the ink supply needle 32.

During the operation period of the recording apparatus, a drive signal is supplied to the elastic wave generating means 3 at a predetermined detection timing, for example, at a constant cycle. The elastic wave generated by the elastic wave generating means 3 propagates on the bottom surface 1a of the container 1, is transmitted to the ink, and propagates the ink.

By attaching the elastic wave generating means 3 to the container 1, a function of detecting the remaining amount can be given to the ink cartridge itself. According to the present invention, it is not necessary to embed an electrode for liquid level detection at the time of molding the container 1,
The injection molding process is simplified, liquid leakage from the electrode embedding region is eliminated, and the reliability of the ink cartridge can be improved.

FIG. 5 shows the elastic wave generating means 3, 15, 16,
And 17 are shown. The fixed substrate 20 is formed of a material such as ceramic that can be fired. First, FIG.
As shown in (I), a conductive material layer 21 to be one electrode is formed on the surface of the fixed substrate 20. Next, as shown in FIG. 5 (II), a green sheet 22 of a piezoelectric material is overlaid on the surface of the conductive material layer 21. Next, as shown in FIG. 5 (III), the green sheet 22 is formed into a predetermined shape by a press or the like into the shape of a vibrator, air-dried, and then fired at a firing temperature, for example, 1200 ° C. Next, FIG. 5 (IV)
As shown in (2), a conductive material layer 23 serving as the other electrode is formed on the surface of the green sheet 22 and is polarized so as to be able to flex and vibrate. Finally, as shown in FIG.
0 is cut for each element. By fixing the fixed substrate 20 to a predetermined surface of the container 1 with an adhesive or the like, the elastic wave generating means 3 is fixed to the predetermined surface of the container 1, and an ink cartridge with a remaining amount detection function is completed.

FIG. 6 shows another embodiment of the elastic wave generating means 3 shown in FIG. In the embodiment of FIG. 5, the conductive material layer 21 is used as a connection electrode. On the other hand, in the embodiment of FIG. 6, the connection terminals 21a and 23a are formed at positions above the surface of the piezoelectric material layer constituted by the green sheet 22 by soldering or the like. Connection terminal 21a
And 23a, the elastic wave generating means 3 can be directly mounted on the circuit board, and the lead wires need not be routed.

By the way, an elastic wave is a kind of wave that can propagate with gas, liquid and solid as a medium.
Therefore, the wavelength, amplitude, phase,
The frequency, propagation direction, propagation speed, etc. change. On the other hand, the state and characteristics of the reflected wave of the elastic wave also differ depending on the change of the medium. Therefore, it is possible to know the state of the medium by using the reflected wave that changes due to the change in the medium through which the elastic wave propagates. When the state of the liquid in the liquid container is detected by this method, for example, an elastic wave transceiver is used. To explain by taking the form of FIGS. 1 to 3 as an example, the transceiver first applies an elastic wave to a medium, for example, a liquid or a liquid container, and the elastic wave propagates through the medium and reaches the surface of the liquid. Since the surface of the liquid has a boundary between the liquid and the gas, the reflected wave is returned to the transceiver. The transceiver receives the reflected wave, and the transmitter or receiver and the surface of the liquid are determined based on the travel time of the reflected wave and the attenuation rate of the elastic wave generated by the transmitter and the amplitude of the reflected wave reflected by the surface of the liquid. And the distance can be measured. By utilizing this, the state of the liquid in the liquid container can be detected. The elastic wave generation means 3 may be used alone as a transceiver in a method utilizing a reflected wave due to a change in a medium through which the elastic wave propagates, or may be separately provided with a dedicated receiver.

As described above, the elastic wave generated by the elastic wave generating means 3 and propagating in the ink liquid is transmitted to the elastic wave generating means 3 by the reflected wave generated on the ink liquid surface depending on the density and the liquid level of the ink liquid. Arrival time changes. Therefore, when the composition of the ink is constant, the arrival time of the reflected wave generated on the surface of the ink liquid depends on the amount of the ink.
Therefore, the amount of ink can be detected by detecting the time from when the elastic wave generating means 3 generates the elastic wave to when the reflected wave from the ink surface reaches the elastic wave generating means 3. In addition, since the elastic waves vibrate particles included in the ink, in the case of a pigment-based ink using a pigment as a colorant, it contributes to preventing precipitation of the pigment and the like.

By providing the elastic wave generating means 3 in the container 1, when the ink in the ink cartridge decreases to near the ink end due to the printing operation or the maintenance operation, and the reflected wave cannot be received by the elastic wave generating means 3, Can determine that the ink is near the end and prompt the user to replace the ink cartridge.

FIG. 7 shows another embodiment of the ink cartridge of the present invention. A plurality of elastic wave generating means 41 to 44 are provided on the side wall of the container 1 at intervals in the vertical direction. The ink cartridge shown in FIG.
The presence or absence of ink at the level of the mounting position of each of the elastic wave generating means 41 to 44 can be detected based on whether or not ink exists at each of the positions 1 to 44. For example, when the water level of the ink is at a level between the elastic wave generators 44 and 43, the elastic wave generator 44 detects that there is no ink, and the elastic wave generators 41, 42, and 43 detect the ink level. Since it is detected that there is, the water level of the ink is at a level between the elastic wave generating means 44 and 43. Therefore, by providing the plurality of elastic wave generating means 41 to 44, the remaining ink amount can be detected stepwise or gradually.

FIGS. 8 and 9 show still another embodiment of the ink cartridge of the present invention. In the embodiment shown in FIG. 8, the bottom surface 1a is formed obliquely in the vertical direction.
The elastic wave generating means 65 is attached to the second. In the embodiment shown in FIG. 9, the elastic wave generating means 66 extending in the vertical direction is provided near the bottom surface of the side wall 1b.

According to the embodiment of FIGS. 8 and 9, when the ink is consumed and a part of the elastic wave generating means 65 and 66 is exposed from the liquid surface, the elastic wave generating means 65 and 66 are turned off.
The arrival time and acoustic impedance of the reflected wave of the generated elastic wave continuously change in accordance with the liquid level changes Δh1 and Δh2. Therefore, by detecting the arrival time of the reflected wave of the elastic wave or the degree of change in the acoustic impedance, it is possible to accurately detect the process from the ink near-end state of the remaining ink amount to the ink end.

As shown in FIG. 8, the container 1 of the ink cartridge has an inclined surface 1a inclined with respect to the liquid level of the ink in the container 1. The elastic wave generating means 65 is provided on an inclined surface. When the ink is consumed and the liquid level of the ink drops by G, if the elastic wave generating means is arranged perpendicular to the liquid level of the ink, the liquid level of the ink follows the elastic wave generating means. Move by G On the other hand, when the elastic wave generating means 65 is disposed at an angle of θ with respect to the ink surface, the ink surface moves by G / sin θ along the elastic wave generating means 65. . Therefore, when the elastic wave generating means is disposed at an angle with respect to the liquid surface of the ink, the distance at which the liquid surface of the ink moves along the elastic wave generating means 65 is greater in the case where the elastic wave generating means is disposed in an inclined manner. Is long.
Therefore, the elastic wave generating means is more sensitive to a change in the ink water level when the elastic wave generating means is arranged inclined than when the elastic wave generating means is arranged perpendicular to the liquid surface of the ink. Therefore, as shown in FIG. 8, by disposing the elastic wave generating means 65 on the inclined surface of the bottom surface of the outer wall of the container 1, it is possible to accurately detect a change in the remaining amount of ink at the ink near end.

In the above-described embodiment, an example has been described in which the ink cartridge is of the type in which ink is directly stored in the liquid container. As another embodiment of the ink cartridge, the above-described elastic wave generating means may be mounted on an ink cartridge of a type in which a porous elastic body is loaded in the container 1 and the porous elastic body is impregnated with liquid ink. Further, in the above-described embodiment, the use of the flexural vibration type piezoelectric vibrator suppresses the size increase of the cartridge.
It is also possible to use a vertical vibration type piezoelectric vibrator. Furthermore, in the above-described embodiment, the same elastic wave generating means transmits and receives elastic waves. In another embodiment, the remaining amount of ink may be detected by using different elastic wave generating means for transmitting and receiving waves.

FIG. 10 shows still another embodiment of the ink cartridge of the present invention. A plurality of elastic wave generating means 65a, 65b, and 65c are provided in the container 1 at intervals in the vertical direction on a bottom surface 1a formed obliquely in the vertical direction. According to this embodiment, the plurality of elastic wave generating means 65
a, 65b, and 65c, depending on whether or not ink exists at each position,
a, at the level of the mounting position of 65b and 65c,
The arrival times of the reflected waves of the elastic waves to the respective elastic wave generating means 65a, 65b and 65c are different. Therefore, each of the elastic wave generating means 65 is scanned, and the elastic wave generating means 65 is scanned.
a, 65b and 65c, by detecting the arrival times of the reflected waves of the elastic waves, the respective elastic wave generating means 6
It is possible to detect the presence or absence of ink at the level of the mounting position of 5a, 65b and 65c. Therefore, the remaining amount of ink can be detected stepwise. For example, the ink level is changed to the elastic wave generating means 65b and the elastic wave generating means 65c.
The elastic wave generating means 65c detects the absence of ink, while the elastic wave generating means 65b and 65b
a detects that ink is present. By comprehensively evaluating these results, it is understood that the ink liquid level is located between the elastic wave generating means 65b and the elastic wave generating means 65c.

FIG. 11 shows still another embodiment of the ink cartridge of the present invention. The ink cartridge shown in FIG. 11 uses a plate 67 to increase the intensity of the reflected wave from the liquid surface.
Is attached to the float 68 to cover the ink liquid surface. The plate 67 is formed of a material having high acoustic impedance and ink resistance, for example, a ceramic plate.

FIG. 12 shows another embodiment of the ink cartridge shown in FIG. In the ink cartridge of FIG. 12, the plate 67 is floated in order to increase the intensity of the reflected wave from the liquid surface, similarly to the ink cartridge of FIG.
8 to cover the ink liquid level. FIG. 12 (A)
The elastic wave generating means 65 is fixed to the bottom surface 1a formed obliquely in the vertical direction. When the remaining amount of ink is reduced and the elastic wave generating means 65 is exposed from the liquid surface, the elastic wave generating means 65 of the reflected wave of the elastic wave generated by the elastic wave generating means 65.
Since the arrival time changes, the presence or absence of ink at the level of the mounting position of the elastic wave generating means 65 can be detected. Since the elastic wave generating means 65 is mounted on the bottom surface 1a which is formed obliquely in the vertical direction, some ink remains in the container 1 even after the elastic wave generating means 65 detects that there is no ink. Thus, the remaining ink amount at the time of the ink near end can be detected.

FIG. 12B shows a case 1 in which a plurality of elastic wave generating means 65a, 65b and 65c are provided on a bottom surface 1a which is formed obliquely in the up-down direction and at intervals in the up-down direction. . According to the embodiment of FIG. 12B, depending on whether or not ink exists at each position of the plurality of elastic wave generating means 65a, 65b, and 65c, each of the elastic wave generating means 65a, 65b, and 65c is determined. The arrival times of the reflected waves to the elastic wave generating means 65a, 65b and 65c at the level of the mounting position are different. Therefore, by scanning each elastic wave generating means 65 and detecting the arrival time of the reflected wave at each elastic wave generating means, the presence or absence of ink at the level of the mounting position of each elastic wave generating means 65a, 65b and 65c is detected. Can be detected. For example, when the ink liquid level is at a level between the elastic wave generating means 65b and the elastic wave generating means 65c, the elastic wave generating means 65c detects the absence of ink, while the elastic wave generating means 65c
b and 65a detect that there is ink. By comprehensively evaluating these results, the ink liquid level is changed to the elastic wave generation means 65.
It can be seen that it is located between b and the elastic wave generating means 65c.

FIG. 13 shows a cross section of another embodiment of the ink jet recording apparatus of the present invention. FIG. 13A shows a cross section of only the ink jet recording apparatus. FIG. 13 (B)
Indicates that the ink cartridge 27
2 shows a cross section when No. 2 is mounted. The carriage 250 that can reciprocate in the width direction of the inkjet recording paper has a recording head 252 on the bottom surface. The carriage 250 has a sub tank unit 256 on the upper surface of the recording head 252. The sub tank unit 256 has the same configuration as the sub tank unit 33 shown in FIG. The sub tank unit 256 has an ink supply needle 254 on the mounting surface side of the ink cartridge 272. Carriage 250
Are provided in the area where the ink cartridge 272 is mounted so as to face the bottom of the ink cartridge 272.
8 The protrusion 258 has elastic wave generation means 260 such as a piezoelectric vibrator.

FIG. 14 shows an embodiment of an ink cartridge suitable for the recording apparatus shown in FIG. FIG. 14 (A)
Indicates an embodiment of an ink cartridge for single color, for example, black ink. The ink cartridge 272 of the present embodiment has a container 274 for storing ink, and an ink supply port 276 joined to the ink supply needle 254 of the recording apparatus. The container 274 has a concave portion 278 that engages with the convex portion 258 on the bottom surface 274a. The recess 278 accommodates an ultrasonic transmission material, for example, a gelling material 280.

The ink supply port 276 has a packing 282,
It has a valve body 286 and a spring 284. Packing 282
Engage with the ink supply needle 254 in a liquid-tight manner. Valve body 286
Is always in elastic contact with the packing 282 by the spring 284. When the ink supply needle 254 is inserted into the ink supply port 276, the valve 286 is pushed by the ink supply needle 254 to open the ink flow path. At an upper portion of the container 274, a semiconductor storage unit 288 storing information on ink and the like of the ink cartridge 272 is mounted.

FIG. 14B shows an embodiment of an ink cartridge containing a plurality of types of ink. Container 290
Is divided into a plurality of areas by the wall, that is, three ink chambers 2.
92, 294, and 296. Each of the ink chambers 292, 294, and 296 is provided with an ink supply port 29.
8, 300 and 302. The bottom surface 29 of the container 290
In the region opposing each of the ink chambers 292, 294, and 296, gelling materials 304, 306, and 308 for transmitting the elastic waves generated by the elastic wave generating means 260 are provided in cylindrical concave portions 310, 312, 314.

When the ink supply port 276 of the ink cartridge 272 is inserted into the ink supply needle 254 of the sub tank unit 256 as shown in FIG.
6 retreats against the spring 284 to form an ink flow path, so that the ink in the ink cartridge 272 flows into the ink chamber 262. At the stage when the ink is filled in the ink chamber 262, a negative pressure is applied to the nozzle openings of the recording head 252 to fill the recording head 252 with the ink, and then the recording operation is performed. When ink is consumed in the recording head 252 by the recording operation, the pressure on the downstream side of the membrane valve 266 decreases, and the membrane valve 266 is separated from the valve body 270 and opened. The ink in the ink chamber 262 flows into the recording head 252 by opening the membrane valve 266. The ink in the ink cartridge 272 flows into the sub-tank unit 256 as the ink flows into the recording head 252.

During the operation of the recording apparatus, a drive signal is supplied to the elastic wave generating means 260 at a predetermined detection timing, for example, at a constant period. The elastic wave generated by the elastic wave generating means 260 is radiated from the convex portion 258, propagates through the gelling material 280 on the bottom surface 274a of the ink cartridge 272, and is transmitted to the ink in the ink cartridge 272. In FIG. 13, the elastic wave generating means 260 is provided on the carriage 250, but the elastic wave generating means 260 may be provided in the sub tank unit 256.

Since the elastic wave generated by the elastic wave generating means 260 propagates in the ink liquid, the reflected wave reflected on the liquid surface reaches the elastic wave generating means 260 depending on the density of the ink liquid and the liquid level of the ink. Time to change. Therefore, when the composition of the ink is constant, the arrival time of the reflected wave generated on the liquid surface depends only on the ink amount. Therefore, the amount of ink in the ink cartridge 272 can be detected by detecting the time until the reflected wave from the ink liquid surface after the excitation of the elastic wave generating means 260 reaches the elastic wave generating means 260. Further, the elastic wave generated by the elastic wave generating means 260 vibrates the particles contained in the ink, so that the precipitation of the pigment or the like is prevented.

When the ink in the ink cartridge 272 decreases to near the ink end due to the printing operation or the maintenance operation, and the reflected wave from the surface of the ink liquid after the elastic wave is generated by the elastic wave generating means 260 cannot be received. , The ink cartridge 272 can be replaced. When the ink cartridge 272 is not mounted on the carriage 250 as specified, the propagation form of the elastic wave by the elastic wave generating means 260 changes extremely. By utilizing this, when an extreme change in the elastic wave is detected, an alarm can be issued to urge the user to check the ink cartridge 272.

The arrival time of the reflected wave of the elastic wave generated by the elastic wave generating means 260 to the elastic wave generating means 260 depends on the container 2
74 is affected by the density of the ink contained in the ink. Since the ink density may differ depending on the type of ink, the data relating to the type of ink contained in the ink cartridge 272 is stored in the semiconductor storage unit 288, and a detection sequence corresponding to the data is executed. The amount can be detected more accurately. In FIG. 13B, the ink cartridge 2
In place of the ink cartridge 74, the ink cartridge shown in FIG.

FIG. 15 shows an ink cartridge 2 of the present invention.
72 shows another embodiment of the present invention. In the ink cartridge 272 shown in FIG. 15, the bottom surface 274a is formed obliquely in the vertical direction. The ink cartridge 272 in FIG.
When the remaining amount of ink becomes small and a part of the irradiation area of the elastic wave of the elastic wave generating means 260 is exposed from the ink surface, the reflected wave of the elastic wave generated by the elastic wave generating means 260 is transmitted to the elastic wave generating means 260. The arrival time is the change Δh1 in the ink level.
Changes continuously in response to Δh1 is the gelling material 28
The difference between the heights of the bottom surface 274a at both ends of 0 is shown. Therefore, by detecting the arrival time of the reflected wave to the elastic wave generating means 260, the process from the ink near end state to the ink end can be accurately detected.

FIG. 16 shows an ink cartridge 2 according to the present invention.
72 shows still another embodiment of the inkjet recording apparatus 72 and the inkjet recording apparatus. The ink jet recording apparatus shown in FIG. 16 has a side surface 274 b on the ink supply port 276 side of the ink cartridge 274.
Has a protrusion 258 '. The protrusion 258 'includes an elastic wave generation means 260'. The gelling material 280 ′ is engaged with the convex portion 258 ′ to
74b. According to the ink cartridge 272 shown in FIG. 16, when the remaining amount of the ink decreases and a part of the elastic wave generation unit 260 'is irradiated from the liquid surface, the elastic wave generated by the elastic wave generation unit 260' The arrival time and acoustic impedance of the reflected wave to the elastic wave generation means 260 'continuously change in accordance with the change Δh2 in the liquid level. Δh2 represents a difference in height between the upper end and the lower end of the gelling material 280 ′. Therefore, the process from the ink near-end state to the ink end can be accurately detected by detecting the arrival time of the reflected wave to the elastic wave generating means 260 'or the degree of change in the acoustic impedance.

In the above embodiment, the container 27
4 has been described by taking an example of an ink cartridge of a type that directly stores ink. In another embodiment, the container 274
The elastic wave generating means 26 is provided in an ink cartridge of a type in which a porous elastic body is loaded into the ink cartridge and the porous elastic body is impregnated with ink.
0 may be applied. Further, in the above embodiment,
When detecting the remaining amount of the ink based on the reflected wave at the liquid surface, the same elastic wave generating means 260 and 260 'transmitted and received the elastic wave. The present invention is not limited to this. For example, as another embodiment, different elastic wave generating means 260 may be used for transmitting and receiving elastic waves.

FIG. 17 shows another embodiment of the ink cartridge 272 shown in FIG. The ink cartridge 272 attaches the plate member 316 to the float 318 and covers the ink liquid surface, thereby increasing the intensity of the reflected wave from the ink liquid surface. The plate material 316 has a high acoustic impedance,
Further, it is preferable to be formed of a material having ink resistance, for example, ceramic or the like. The elastic wave generating means 3
Is preferably provided on the bottom surface of the outer wall of the ink cartridge which is below the liquid level of the ink. However, as shown in FIGS. 9 and 16, it is sufficient that the ink surface can be detected even when the ink surface is provided on various surfaces.

FIGS. 18 and 19 show details and an equivalent circuit of an actuator 106 which is an embodiment of the piezoelectric device. The actuator referred to here is used in a method of detecting at least a change in acoustic impedance and detecting a consumption state of the liquid in the liquid container. In particular, it is used in a method of detecting a resonance frequency by residual vibration to detect at least a change in acoustic impedance to detect a consumption state of a liquid in a liquid container. FIG. 18A is an enlarged plan view of the actuator 106. FIG. 18 (B)
Shows a BB cross section of the actuator 106. FIG.
(C) shows a CC cross section of the actuator 106.
FIGS. 19A and 19B show an equivalent circuit of the actuator 106. 19 (C) and 19 (D) show the periphery including the actuator 106 when the ink is filled in the ink cartridge and its equivalent circuit, respectively, and FIGS. 19 (E) and 19 (F). () Shows the periphery including the actuator 106 when there is no ink in the ink cartridge and its equivalent circuit.

The actuator 106 includes a substrate 178 having a circular opening 161 at substantially the center, a vibration plate 176 provided on one surface (hereinafter referred to as a surface) of the substrate 178 so as to cover the opening 161, A piezoelectric layer 160 disposed on the side of the surface of the plate 176; and upper and lower electrodes 164 and 166 sandwiching the piezoelectric layer 160 from both sides.
And upper electrode terminal 1 electrically coupled to upper electrode 164
68, a lower electrode terminal 170 electrically coupled to the lower electrode 166, an upper electrode 164 and an upper electrode terminal 168.
And an auxiliary electrode 172 electrically connected therebetween. Each of the piezoelectric layer 160, the upper electrode 164, and the lower electrode 166 has a circular portion as a main part. Each circular portion of the piezoelectric layer 160, the upper electrode 164, and the lower electrode 166 forms a piezoelectric element.

The vibration plate 176 is formed on the surface of the substrate 178 so as to cover the opening 161. Cavity 162
Is the portion of the diaphragm 176 facing the opening 161 and the substrate 17
8 is formed by the opening 161 on the surface. Substrate 17
The surface opposite to the piezoelectric element 8 (hereinafter referred to as the back surface) faces the liquid container side, and the cavity 162 is configured to be in contact with the liquid. The vibration plate 176 is attached to the substrate 178 in a liquid-tight manner so that even if the liquid enters the cavity 162, the liquid does not leak to the surface side of the substrate 178.

The lower electrode 166 is located on the surface of the vibration plate 176, that is, the surface opposite to the liquid container.
It is attached so that the center of the circular portion which is the main part of 66 and the center of the opening 161 substantially coincide with each other. The area of the circular portion of the lower electrode 166 is set to be smaller than the area of the opening 161. On the other hand, the lower electrode 1
The piezoelectric layer 160 is formed on the surface side of the substrate 66 such that the center of the circular portion substantially coincides with the center of the opening 161. The area of the circular portion of the piezoelectric layer 160 is
, And larger than the area of the circular portion of the lower electrode 166.

On the other hand, on the front surface side of the piezoelectric layer 160, an upper electrode 164 is provided at the center of the circular portion which is the main portion thereof and the opening 1
61 are formed so as to substantially coincide with the center. The area of the circular portion of the upper electrode 164 is smaller than the area of the opening 161 and the circular portion of the piezoelectric layer 160, and the lower electrode 1
The area is set to be larger than the area of the circular portion 66.

Therefore, the main part of the piezoelectric layer 160 is sandwiched by the main part of the upper electrode 164 and the main part of the lower electrode 166 from the front side and the back side, respectively. The deformation driving can be performed effectively. The circular portions that are the main parts of the piezoelectric layer 160, the upper electrode 164, and the lower electrode 166 form the piezoelectric element of the actuator 106. As described above, the piezoelectric element is in contact with the vibration plate 176. Of the circular portion of the upper electrode 164, the circular portion of the piezoelectric layer 160, the circular portion of the lower electrode 166, and the opening 161, the opening 161 has the largest area. With this structure, the vibration area of the vibration plate 176 that actually vibrates is determined by the opening 161. The circular portion of the upper electrode 164, the circular portion of the piezoelectric layer 160, and the lower electrode 16
Since the circular portion 6 has a smaller area than the opening 161, the diaphragm 176 is more likely to vibrate. Further, the piezoelectric layer 16
Of the circular portion of the lower electrode 166 and the circular portion of the upper electrode 164 electrically connected to 0, the circular portion of the lower electrode 166 is smaller. Therefore, the circular portion of the lower terminal 166 determines a portion of the piezoelectric layer 160 where the piezoelectric effect occurs.

The upper electrode terminal 168 is formed on the surface of the diaphragm 176 so as to be electrically connected to the upper electrode 164 via the auxiliary electrode 172. On the other hand, the lower electrode terminal 17
0 is formed on the surface side of diaphragm 176 so as to be electrically connected to lower electrode 166. Since the upper electrode 164 is formed on the surface side of the piezoelectric layer 160, the upper electrode terminal 16
8, it is necessary to have a step equal to the sum of the thickness of the piezoelectric layer 160 and the thickness of the lower electrode 166. It is difficult to form this step only with the upper electrode 164, and even if possible, the connection between the upper electrode 164 and the upper electrode terminal 168 is weakened, and there is a risk of disconnection. Therefore, the upper electrode 164 and the upper electrode terminal 16 are formed by using the auxiliary electrode 172 as an auxiliary member.
8 is connected. By doing so, both the piezoelectric layer 160 and the upper electrode 164 have a structure supported by the auxiliary electrode 172, so that a desired mechanical strength can be obtained, and the connection between the upper electrode 164 and the upper electrode terminal 168 is ensured. It becomes possible to.

It should be noted that the piezoelectric element and the vibrating region of the diaphragm 176 facing the piezoelectric element correspond to the actuator 106.
Is a vibrating part that actually vibrates. Further, the members included in the actuator 106 are preferably integrally formed by firing each other. By forming the actuator 106 integrally, handling of the actuator 106 becomes easy. Further, the vibration characteristics are improved by increasing the strength of the substrate 178. That is, by increasing the strength of the substrate 178, only the vibrating portion of the actuator 106 vibrates, and portions of the actuator 106 other than the vibrating portion do not vibrate. Also, in order to prevent portions other than the vibrating portion of the actuator 106 from vibrating, it is possible to increase the strength of the substrate 178 while making the piezoelectric element of the actuator 106 thinner and smaller and the diaphragm 176 thinner.

As the material of the piezoelectric layer 160, it is preferable to use lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT) or a lead-free piezoelectric film not using lead. Alternatively, it is preferable to use alumina. It is preferable that the same material as the substrate 178 be used for the diaphragm 176. For the upper electrode 164, the lower electrode 166, the upper electrode terminal 168, and the lower electrode terminal 170, a conductive material such as a metal such as gold, silver, copper, platinum, aluminum, or nickel can be used.

The actuator 106 configured as described above can be applied to a container for storing a liquid. For example, it can be mounted on an ink cartridge or ink tank used for an ink jet recording apparatus, or a container containing a cleaning liquid for cleaning a recording head.

The actuator 106 shown in FIG. 18 and FIG.
62 is attached so as to be in contact with the liquid contained in the liquid container. When the liquid is sufficiently stored in the liquid container, the inside and outside of the cavity 162 are filled with the liquid. On the other hand, the liquid in the liquid container is consumed,
When the liquid level drops below the mounting position of the actuator,
No liquid exists in the cavity 162, or the liquid remains only in the cavity 162 and a gas exists outside thereof. The actuator 106 is
At least a difference in acoustic impedance due to the change in the state is detected. Thereby, the actuator 106 can detect whether the liquid container is in a state where the liquid is sufficiently stored or whether the liquid container is in a state where a certain amount or more of the liquid is consumed. Further, the actuator 106 can also detect the type of liquid in the liquid container.

Here, the principle of liquid level detection by the actuator will be described.

To detect a change in the acoustic impedance of the medium, the impedance characteristics or admittance characteristics of the medium are measured. When measuring the impedance characteristic or the admittance characteristic, for example, a transmission circuit can be used. The transmission circuit applies a constant voltage to the medium, changes the frequency, and measures the current flowing through the medium. Alternatively, the transmission circuit supplies a constant current to the medium, changes the frequency, and measures the voltage applied to the medium. A change in the current value or voltage value measured by the transmission circuit indicates a change in acoustic impedance. Further, a change in the frequency fm at which the current value or the voltage value becomes maximum or minimum also indicates a change in acoustic impedance.

Apart from the method described above, the actuator
A change in the acoustic impedance of the liquid can be detected using only a change in the resonance frequency. As a method using the change in acoustic impedance of the liquid, when using a method of detecting a resonance frequency by measuring a back electromotive force generated by residual vibration remaining in the vibrating portion after the vibrating portion of the actuator vibrates, for example, A piezoelectric element can be used. A piezoelectric element is an element that generates a back electromotive force due to residual vibration remaining in a vibrating part of an actuator, and the magnitude of the back electromotive force changes according to the amplitude of the vibrating part of the actuator. Therefore, the larger the amplitude of the vibrating part of the actuator, the easier it is to detect. Further, the cycle at which the magnitude of the back electromotive force changes depends on the frequency of the residual vibration in the vibrating portion of the actuator. Therefore, the frequency of the vibrating part of the actuator corresponds to the frequency of the back electromotive force. Here, the resonance frequency refers to a frequency in a resonance state between the vibrating portion of the actuator and the medium in contact with the vibrating portion.

In order to obtain the resonance frequency fs, the waveform obtained by the back electromotive force measurement when the vibrating section and the medium are in a resonance state is subjected to Fourier transform. The vibration of the actuator is not only deformed in one direction but is accompanied by various deformations such as bending and elongation, and thus has various frequencies including the resonance frequency fs. Therefore, the resonance frequency fs is determined by Fourier-transforming the waveform of the back electromotive force when the piezoelectric element and the medium are in a resonance state, and specifying the most dominant frequency component.

The frequency fm is a frequency when the admittance of the medium is maximum or the impedance is minimum. Assuming that the resonance frequency is fs, the frequency fm is equal to the resonance frequency fs due to dielectric loss or mechanical loss of the medium.
Causes a slight error. However, deriving the resonance frequency fs from the actually measured frequency fm is troublesome, and therefore, generally, the frequency fm is used instead of the resonance frequency. Here, by inputting the output of the actuator 106 to the transmission circuit, the actuator 106 can detect at least the acoustic impedance.

The frequency fm is measured by measuring the impedance characteristic or admittance characteristic of the medium, and the resonance frequency fs is measured by measuring the back electromotive force generated by the residual vibration in the vibrating part of the actuator. It has been proved by experiments that there is almost no difference in the resonance frequencies to be obtained.

The vibration region of the actuator 106 is a portion of the vibration plate 176 that forms the cavity 162 determined by the opening 161. When the liquid is sufficiently contained in the liquid container, the cavity 162 is filled with the liquid, and the vibrating region comes into contact with the liquid in the liquid container. On the other hand, if there is not enough liquid in the liquid container, the vibrating region will be in contact with the liquid remaining in the cavity in the liquid container, or will not be in contact with the liquid, but will be in contact with gas or vacuum.

The actuator 106 of the present invention is provided with the cavity 162 so that the liquid in the liquid container can be designed to remain in the vibration region of the actuator 106. The reason is as follows.

Depending on the mounting position and the mounting angle of the actuator on the liquid container, the liquid adheres to the vibration area of the actuator even though the liquid level in the liquid container is below the mounting position of the actuator. In some cases. When the actuator detects the presence / absence of the liquid only by the presence / absence of the liquid in the vibration region, the liquid attached to the vibration region of the actuator prevents accurate detection of the presence / absence of the liquid. For example, when the liquid level is below the mounting position of the actuator, the liquid container swings due to the reciprocating movement of the carriage or the like, causing the liquid to wave,
If the droplets adhere to the vibrating area, the actuator incorrectly determines that there is sufficient liquid in the liquid container. Therefore, conversely, even if the liquid remains there, by positively providing a cavity designed to accurately detect the presence or absence of the liquid, the liquid container rocked and the liquid surface wavy However, malfunction of the actuator can be prevented. As described above, malfunction can be prevented by using the actuator having the cavity.

As shown in FIG. 19 (E), the case where there is no liquid in the liquid container and the liquid in the liquid container remains in the cavity 162 of the actuator 106 is defined as the threshold for the presence or absence of the liquid. That is, when there is no liquid around the cavity 162 and the amount of liquid in the cavity is smaller than this threshold, it is determined that there is no ink. When there is liquid around the cavity 162 and there is more liquid than this threshold, there is ink. to decide. For example, when the actuator 106 is mounted on the side wall of the liquid container, it is determined that there is no ink when the liquid in the liquid container is below the mounting position of the actuator, and the liquid in the liquid container is positioned above the mounting position of the actuator. If there is, it is determined that there is ink. By setting the threshold value in this manner, it is determined that there is no ink even when the ink in the cavity has dried and the ink has run out. Since the threshold value is not exceeded even if the ink adheres to the cavity, it can be determined that there is no ink.

Here, the operation and principle of detecting the state of the liquid in the liquid container from the resonance frequency of the medium and the vibrating portion of the actuator 106 by measuring the back electromotive force will be described with reference to FIGS. 18 and 19. In the actuator 106, a voltage is applied to the upper electrode 164 and the lower electrode 166 via the upper electrode terminal 168 and the lower electrode terminal 170, respectively. Of the piezoelectric layer 160,
An electric field is generated in a portion sandwiched between the upper electrode 164 and the lower electrode 166. The piezoelectric layer 160 is deformed by the electric field. When the piezoelectric layer 160 is deformed, the diaphragm 1
The vibration area of 76 vibrates flexibly. Piezoelectric layer 160
For a while after the deformation, the flexural vibration remains in the vibrating portion of the actuator 106.

The residual vibration is free vibration between the vibration part of the actuator 106 and the medium. Therefore, by making the voltage applied to the piezoelectric layer 160 a pulse waveform or a rectangular wave, a resonance state between the vibrating portion and the medium can be easily obtained after the voltage is applied. The residual vibration is
In order to vibrate the vibrating portion 06, the piezoelectric layer 160 is also deformed. Therefore, the piezoelectric layer 160 generates a back electromotive force. The back electromotive force is detected via the upper electrode 164, the lower electrode 166, the upper electrode terminal 168, and the lower electrode terminal 170. Since the resonance frequency can be specified by the detected back electromotive force, the state of the liquid in the liquid container can be detected.

In general, the resonance frequency fs is expressed by fs = 1 / (2 * π * (M * Cact) ^1/2 ) (Equation 1). Here, M is the inertance Mact of the vibrating part.
And the additional inertance M ′. Cact is the compliance of the vibrating part.

FIG. 18C is a sectional view of the actuator 106 when no ink remains in the cavity in this embodiment. FIGS. 19A and 19B
Is an equivalent circuit of the vibrating section of the actuator 106 and the cavity 162 when no ink remains in the cavity.

Mact is obtained by dividing the product of the thickness of the vibrating portion and the density of the vibrating portion by the area of the vibrating portion. More specifically, as shown in FIG. 2) is expressed as Here, Mpzt is the product of the thickness of the piezoelectric layer 160 in the vibrating portion and the density of the piezoelectric layer 160,
It is divided by the area of 0. Melectrode1 is obtained by dividing the product of the thickness of the upper electrode 164 and the density of the upper electrode 164 in the vibrating section by the area of the upper electrode 164. M
electrode2 is the product of the product of the thickness of the lower electrode 166 and the density of the lower electrode 166 in the vibrating section divided by the area of the lower electrode 166. Mvib is the diaphragm 1 in the vibrating section.
The product of the thickness of the diaphragm 76 and the density of the diaphragm 176 is
Of the vibration region. However, Mact
In this embodiment, the piezoelectric layer 160 and the piezoelectric layer 160 can be calculated from the thickness, density, and area of the entire vibrating portion.
Although the respective areas of the upper electrode 164, the lower electrode 166, and the vibration region of the diaphragm 176 have the magnitude relationship as described above, it is preferable that the difference between the areas is small. In the present embodiment, it is preferable that portions of the piezoelectric layer 160, the upper electrode 164, and the lower electrode 166 other than the circular portion, which are main portions thereof, are so small as to be negligible with respect to the main portion. Therefore, in the actuator 106, Mact is the upper electrode 164,
This is the sum of the inertances of the lower electrode 166, the piezoelectric layer 160, and the vibration area of the vibration plate 176. The compliance Cact is a compliance of a portion formed by the vibration region of the upper electrode 164, the lower electrode 166, the piezoelectric layer 160, and the vibration plate 176.

19 (A), 19 (B) and 19
(D) and FIG. 19 (F) show equivalent circuits of the vibrating section of the actuator 106 and the cavity 162. In these equivalent circuits, Cact indicates compliance of the vibrating section of the actuator 106. Cpzt, Celectrode
1, Celectrode2 and Cvib indicate compliance of the piezoelectric layer 160, the upper electrode 164, the lower electrode 166, and the diaphragm 176 in the vibrating portion, respectively. Cact is represented by the following equation 3.

1 / Cact = (1 / Cpzt) + (1 / Celectrode1) + (1 / Celectrode2) + (1 / Cvi b) (Equation 3) From Equations 2 and 3, FIG. It can also be expressed as 19 (B).

The compliance Cact represents a volume that can receive a medium by deformation when pressure is applied to a unit area of the vibrating portion. Further, the compliance Cact may be said to indicate the ease of deformation.

FIG. 19C is a sectional view of the actuator 106 in a case where the liquid is sufficiently contained in the liquid container and the periphery of the vibration region of the actuator 106 is filled with the liquid. M′max in FIG. 19C represents the maximum value of the additional inertance when the liquid is sufficiently contained in the liquid container and the liquid is filled around the vibration region of the actuator 106. M'max is

M′max = (π * ρ / (2 * k ³ )) * (2 * (2 * k * a) ³ / (3 * π)) / (π * a ² ) ² (Equation 4) (A is the radius of the vibrating part, ρ is the density of the medium, and k is the wave number.)

Is represented by Expression 4 holds when the vibration region of the actuator 106 is a circle having a radius a. The additional inertance M ′ is a quantity indicating that the mass of the vibrating part is apparently increased by the action of the medium near the vibrating part. As can be seen from Equation 4, M′max
Varies greatly depending on the radius a of the vibrating portion and the density ρ of the medium.

The wave number k is as follows: k = 2 * π * fact / c (Equation 5) (Fact is the resonance frequency of the vibrating portion when the liquid is not touching. C is the speed of sound propagating in the medium. .)

Is represented by

FIG. 19D shows the vibrating portion and the cavity 162 of the actuator 106 in the case of FIG. 19C in which the liquid is sufficiently contained in the liquid container and the liquid is filled around the vibrating region of the actuator 106. Is shown.

FIG. 19E shows the state of the actuator 106 when the liquid in the liquid container is consumed and there is no liquid around the vibration region of the actuator 106 but the liquid remains in the cavity 162 of the actuator 106. FIG. Equation 4 is an equation representing the maximum inertance M′max determined from the density ρ of the ink when the liquid container is filled with the liquid, for example. On the other hand, when the liquid in the liquid container is consumed and the liquid around the vibration region of the actuator 106 becomes gas or vacuum while the liquid remains in the cavity 162,

M ′ = ρ * t / S (Equation 6) t is the thickness of the medium involved in the vibration. S
Is the area of the vibration region of the actuator 106. When this vibration region is a circle having a radius a, S = π * a ² . Therefore, the additional inertance M ′ follows Expression 4 when the liquid is sufficiently stored in the liquid container and the liquid is filled around the vibration region of the actuator 106. On the other hand, when the liquid is consumed and the liquid around the vibration region of the actuator 106 becomes gas or vacuum while the liquid remains in the cavity 162, Equation 6 is followed.

Here, as shown in FIG. 19E, the liquid in the liquid container is consumed, and there is no liquid around the vibration region of the actuator 106, but the liquid remains in the cavity 162 of the actuator 106. In this case, the additional inertance M ′ is M′cav for convenience, and is distinguished from the additional inertance M′max when the liquid is filled around the vibration region of the actuator 106.

FIG. 19F shows that the liquid in the liquid container is consumed, and there is no liquid around the vibration region of the actuator 106, but the liquid remains in the cavity 162 of the actuator 106. 5 shows an equivalent circuit of the vibrating section of the actuator 106 and the cavity 162 in the case of FIG.

Here, the parameters relating to the state of the medium are the density ρ of the medium and the thickness t of the medium in Equation 6. When the liquid is sufficiently stored in the liquid container, the liquid comes into contact with the vibrating portion of the actuator 106. When the liquid is not sufficiently stored in the liquid container, the liquid remains in the cavity or Alternatively, gas or vacuum comes into contact with the vibrating portion of the actuator 106. The liquid around the actuator 106 is consumed, and FIG.
Assuming that the additional inertance in the process of shifting from M′max of FIG. 19 to M′cav of FIG. 19E is M ′ var, the thickness t of the medium changes depending on the storage state of the liquid in the liquid container. M′var changes, and the resonance frequency fs also changes. Therefore, by specifying the resonance frequency fs, the presence or absence of the liquid in the liquid container can be detected. Here, as shown in FIG.
= D, M′cav is expressed using Equation 6, and Equation 6
Substituting the cavity depth d for t

M′cav = ρ * d / S (Equation 7)

Further, even if the mediums are liquids of different types, the added inertance M 'changes and the resonance frequency fs changes because the density ρ differs depending on the composition. Therefore, the type of liquid can be detected by specifying the resonance frequency fs. When only one of ink and air comes into contact with the vibrating portion of the actuator 106 and is not mixed, even if it is calculated by Equation 4, M ′
Can be detected.

FIG. 20A is a graph showing the relationship between the amount of ink in the ink tank and the resonance frequency fs of the ink and the vibrating section. Here, an ink will be described as an example of the liquid. The vertical axis indicates the resonance frequency fs, and the horizontal axis indicates the ink amount. When the ink composition is constant, the resonance frequency fs increases with a decrease in the remaining amount of ink.

When the ink is sufficiently contained in the ink container and the periphery of the vibration region of the actuator 106 is filled with ink, the maximum additional inertance M′max
Is the value represented by Equation 4. On the other hand, when the ink is consumed and the ink is not filled around the vibration region of the actuator 106 while the liquid remains in the cavity 162, the additional inertance M′var is calculated based on the thickness t of the medium. It is calculated by Since t in Expression 6 is the thickness of the medium involved in the vibration, the actuator 1
By making d (see FIG. 18B) of the cavity 162 of 06 small, that is, by making the substrate 178 sufficiently thin,
A process in which the ink is gradually consumed can also be detected (see FIG. 19C). Here, tink is the thickness of the ink relating to the vibration, and tink-max is tink at M′max. For example, the actuator 106 is provided on the bottom surface of the ink cartridge substantially horizontally with respect to the ink level. When the ink is consumed and the liquid level of the ink reaches the height of tink-max or less from the actuator 106, M′var gradually changes according to Equation 6, and the resonance frequency fs gradually changes according to Equation 1. Therefore, as long as the ink level is within the range of t, the actuator 106 can gradually detect the ink consumption state.

Further, by increasing or lengthening the vibration area of the actuator 106 and arranging the actuator 106 vertically, according to the position of the liquid surface due to ink consumption, S
Changes. Therefore, the actuator 106 can also detect a process in which the ink is gradually consumed. For example, the actuator 10 is provided on the side wall of the ink cartridge.
6 is arranged substantially perpendicular to the ink level. When the ink is consumed and the liquid level of the ink reaches the vibration region of the actuator 106, the additional inertance M ′ decreases as the water level decreases, so that the resonance frequency fs gradually increases according to Equation 1. Therefore, the liquid level of the ink is
2 within the range of the diameter 2a (see FIG. 19C).
The actuator 106 can gradually detect the ink consumption state.

A curve X in FIG.
6 shows the relationship between the amount of ink contained in the ink tank and the ink and the resonance frequency fs of the vibrating part when the cavity 162 of the actuator 06 is made sufficiently shallow or when the vibration region of the actuator 106 is made sufficiently large or long. ing. It can be understood that as the amount of ink in the ink tank decreases, the resonance frequency fs of the ink and the vibrating part gradually changes.

More specifically, the case where the process in which the ink is gradually consumed can be detected means that both the liquid and the gas having different densities exist around the vibrating region of the actuator 106, and This is the case related to vibration. As the ink is gradually consumed,
In the medium related to the vibration around the vibration region of the actuator 106, the liquid increases while the gas increases.
For example, in a case where the actuator 106 is disposed horizontally with respect to the ink level, and when tink is smaller than tink-max, the medium involved in the vibration of the actuator 106 includes both ink and gas. Therefore, assuming that the area S of the vibration region of the actuator 106 is:
When the state of M'max or less is represented by the added mass of ink and gas,

M ′ = M′air + M′ink = ρair * tair / S + ρink * tink / S (Equation 8) Here, M'air is the inertance of air, and M'ink is the inertance of ink. ρair is the density of air, and ρink is the density of the ink. tair is the thickness of the air involved in the vibration, and tink is the thickness of the ink involved in the vibration. As the liquid decreases and the gas increases in the medium related to the vibration around the vibration region of the actuator 106, tair increases when the actuator 106 is arranged substantially horizontally with respect to the ink level, tink decreases. Thereby,
M'var gradually decreases, and the resonance frequency gradually increases. Therefore, the amount of ink remaining in the ink tank or the amount of consumed ink can be detected. It should be noted that the reason why only the density of the liquid is used in Equation 7 is that it is assumed that the density of the air is negligibly small compared to the density of the liquid.

When the actuator 106 is disposed substantially perpendicular to the ink surface, the medium related to the vibration of the actuator 106 in the vibration area of the actuator 106 and the vibration area of the actuator 106 The medium involved is considered as an equivalent circuit (not shown) in parallel with the region of the gas. Actuator 10
The medium relating to the vibration of No. 6 has the area of the ink-only area as S
Assuming that the area of the region where only the medium relating to the vibration of the actuator 106 is gas is Sair,

1 / M ′ = 1 / M′air + 1 / M′ink = Sair / (ρair * tair) + Sink / (ρink * tink) (Equation 9)

Equation 9 is applied when ink is not held in the cavity of the actuator 106. The case where the ink is held in the cavity of the actuator 106 can be calculated by Expressions 7, 8, and 9.

On the other hand, when the substrate 178 is thick, that is, when the depth d of the cavity 162 is deep and d is relatively close to the medium thickness tink-max, or when the vibration region is very large compared to the height of the liquid container. When a smaller actuator is used, it is actually detected that the ink level is higher and lower than the mounting position of the actuator, rather than detecting the process of gradually decreasing the ink. In other words, the presence or absence of ink in the vibration region of the actuator is detected. For example, the curve Y in FIG. 20A shows the relationship between the amount of ink in the ink tank and the ink and the resonance frequency fs of the vibrating part in the case of a small circular vibration region.
A state is shown in which the resonance frequency fs of the ink and the vibrating part changes drastically between the ink amounts Q before and after the liquid level of the ink in the ink tank passes through the mounting position of the actuator. From this, it is possible to detect whether a predetermined amount of ink remains in the ink tank.

FIG. 20B shows the relationship between the ink density and the resonance frequency fs of the ink and the vibrating section in the curve Y of FIG. 20A. Ink is given as an example of the liquid. As shown in FIG. 20B, when the ink density increases, the additional inertance increases, so that the resonance frequency fs
Decrease. That is, the resonance frequency fs differs depending on the type of ink. Therefore, by measuring the resonance frequency fs, it is possible to confirm whether inks having different densities are mixed when the ink is refilled.

That is, it is possible to identify ink tanks containing different types of ink.

Subsequently, when the size and shape of the cavity are set so that the liquid remains in the cavity 162 of the actuator 106 even when the liquid in the liquid container is empty, the state of the liquid is accurately detected. The possible conditions will be described in detail. If the actuator 106 can detect the state of the liquid when the cavity 162 is filled with the liquid,
Even when the cavity 162 is not filled with the liquid, the state of the liquid can be detected.

The resonance frequency fs is a function of the inertance M. The inertance M is the inertance Mac of the vibrating part.
It is the sum of t and the additional inertance M '. Here, the additional inertance M ′ is related to the state of the liquid. The additional inertance M ′ is an amount indicating that the mass of the vibrating part is apparently increased by the action of the medium near the vibrating part. That is, it means an increase in the mass of the vibrating section due to apparent absorption of the medium by the vibration of the vibrating section.

Therefore, when M'cav is larger than M'max in Equation 4, all the apparently absorbing media are liquids remaining in the cavity 162. Therefore, it is the same as the state where the liquid is filled in the liquid container. In this case, since M ′ does not change, the resonance frequency fs does not change. Therefore, the actuator 106 cannot detect the state of the liquid in the liquid container.

On the other hand, when M′cav is smaller than M′max in Equation 4, the medium apparently absorbed is the liquid remaining in the cavity 162 and the gas or vacuum in the liquid container. At this time, unlike the state where the liquid is filled in the liquid container, M ′ changes, so that the resonance frequency fs changes. Therefore, the actuator 106
The state of the liquid in the liquid container can be detected.

That is, when the liquid in the liquid container is empty and the liquid remains in the cavity 162 of the actuator 106, the condition under which the actuator 106 can accurately detect the liquid state is that M'cav is M'cav. It is smaller than max. The condition M′max> M′cav at which the actuator 106 can accurately detect the state of the liquid is defined as the cavity 1
Regardless of the shape of 62.

Here, M'cav is the mass of the liquid having a volume substantially equal to the volume of the cavity 162. Therefore,
From the inequality M′max> M′cav, the actuator 106
The conditions under which the liquid state can be accurately detected are cavity 1
It can be expressed as a condition of a capacity of 62. For example, let a be the radius of the opening 161 of the circular cavity 162,
And the depth of the cavity 162 is d,

M′max> ρ * d / πa ² (Equation 10). Expanding Equation 10 gives

The condition of a / d> 3 * π / 8 (Equation 11) is required. Equations 10 and 11 are
This is true only when the shape of the bitty 162 is circular. Round
Πa in equation 10 using the equation of M′max ^TwoTo
By calculating the area of the cavity, the width of the cavity and
The relationship between dimensions such as length and depth can be derived.

Therefore, the radius of the opening 161 satisfying the equation (11)
a and cavity 1 at depth d of cavity 162
The actuator 106 having 62 can detect the state of the liquid without malfunction even if the liquid in the liquid container is empty and the liquid remains in the cavity 162.

Since the additional inertance M ′ also affects the acoustic impedance characteristics, it can be said that the method of measuring the back electromotive force generated in the actuator 106 due to the residual vibration detects at least a change in the acoustic impedance.

Further, according to the present embodiment, the back electromotive force generated in the actuator 106 by the residual vibration after the actuator 106 generates the vibration is measured. However, it is not always necessary for the vibrating section of the actuator 106 to vibrate the liquid by its own vibration due to the drive voltage. That is, even if the vibrating part does not oscillate by itself, it vibrates together with a certain range of liquid in contact with the vibrating part, whereby the piezoelectric layer 160 bends and deforms. This residual vibration generates a back electromotive force voltage in the piezoelectric layer 160, and the upper electrode 164
And the lower electromotive force voltage to lower electrode 166.
The state of the medium may be detected by utilizing this phenomenon. For example, in an ink jet recording apparatus, even if the state of the ink tank or the ink inside the ink tank is detected by using the vibration around the vibration part of the actuator generated by the vibration due to the reciprocating movement of the carriage due to the scan of the print head during printing. Good.

FIGS. 21A and 21B show the actuator 1 after the actuator 106 is vibrated.
6 shows a waveform of the residual vibration and a method of measuring the residual vibration.
Up and down of the ink level at the mounting position level of the actuator 106 in the ink cartridge can be detected by a change in the frequency or amplitude of the residual vibration after the actuator 106 oscillates. 21A and 21B, the vertical axis represents the actuator 106.
Represents the voltage of the back electromotive force generated by the residual vibration, and the horizontal axis represents time. Due to the residual vibration of the actuator 106, a voltage analog signal waveform is generated as shown in FIGS. 21 (A) and 21 (B). Next, the analog signal is converted into a digital numerical value corresponding to the frequency of the signal.

In the example shown in FIGS. 21 (A) and 21 (B), the presence or absence of ink is measured by measuring the time during which four pulses from the fourth pulse to the eighth pulse of the analog signal are generated. To detect.

More specifically, the number of times that the actuator 106 oscillates and crosses a predetermined reference voltage from a low voltage side to a high voltage side after oscillation is counted. A digital signal between 4 and 8 counts is defined as High,
The time from 4 counts to 8 counts is measured by a predetermined clock pulse.

FIG. 21A shows a waveform when the ink level is higher than the mounting position level of the actuator 106. FIG. 21A shows a waveform when the ink level is between the upper end and the lower end of the vibration region of the actuator 106. Further, FIG. 21 (C) shows the actuator 1
It is a waveform when there is no ink at the mounting position level 06. 21 (A) and FIG. 21 (C),
21A shows that the time from 4 counts to 8 counts is longer than that of FIG. 21C. In other words, the time from 4 counts to 8 counts differs depending on the presence or absence of ink. The ink consumption state can be detected using the difference in the time. 4 of analog waveform
The reason for counting from the count is to start the measurement after the vibration of the actuator 106 is stabilized. Starting from the fourth count is merely an example, and counting from an arbitrary count may be performed. Here, signals from the 4th to 8th counts are detected, and the time from the 4th to 8th counts is measured by a predetermined clock pulse. Thereby, the resonance frequency is obtained. The clock pulse is preferably a clock pulse equal to a clock for controlling a semiconductor memory device or the like attached to the ink cartridge. It is not necessary to measure the time up to the eighth count, and the time may be counted up to an arbitrary count. In FIG. 21, the time from the fourth count to the eighth count is measured, but the time within a different count interval may be detected according to the circuit configuration for detecting the frequency.

For example, when the ink quality is stable and the fluctuation of the peak amplitude is small, the resonance frequency is obtained by detecting the time from the fourth count to the sixth count in order to increase the detection speed. You may. When the ink quality is unstable and the pulse amplitude fluctuates greatly, the time from the fourth count to the twelfth count may be detected in order to accurately detect the residual vibration.

As another embodiment, the wave number of the voltage waveform of the back electromotive force within a predetermined period may be counted (not shown). The resonance frequency can also be obtained by this method. More specifically, after the actuator 106 oscillates, the digital signal is set to High only for a predetermined period, and the number of times the predetermined reference voltage crosses the low voltage side to the high voltage side is counted. By measuring the count, the presence or absence of ink can be detected.

Further, as can be seen by comparing FIGS. 21A and 21C, the back electromotive force differs between when the ink is filled in the ink cartridge and when the ink is not in the ink cartridge. Waveform amplitude is different. Therefore, the consumption state of the ink in the ink cartridge may be detected by measuring the amplitude of the back electromotive force waveform without obtaining the resonance frequency. More specifically, for example, a reference voltage is set between the top of the back electromotive force waveform of FIG. 21A and the top of the back electromotive force waveform of FIG. 21C. After the actuator 106 oscillates, the digital signal is set to High for a predetermined time, and when the back electromotive force crosses the reference voltage, it is determined that there is no ink. If the back electromotive force waveform does not cross the reference voltage, it is determined that there is ink.

In the process of lowering the ink level from the upper end to the lower end of the actuator 106 with respect to the ink level, as the position of the ink level lowers, as shown in FIG.
The frequency and amplitude gradually change from (A) to FIG. 21 (B) and FIG. 21 (C). For example, the time from the fourth count to the eighth count in FIGS. 21A, 21B, and 21C changes to Ta, Tb, and Tc, respectively. However, Tb is longer than Ta, and Tc is longer than Tb. In addition, FIG. 21 (A), FIG. 21 (B) and FIG.
Vary from a1, a2 and a3, respectively.
However, a2 is larger than a1 and a3 is larger than a2. Therefore, from FIG. 21 (A) to FIG. 21 (B), FIG.
In the process of shifting to 1 (C), the actuator 1
By measuring the back electromotive force at which 06 occurs, the remaining amount of ink can be detected in detail.

FIG. 22 shows a method of manufacturing the actuator 106. A plurality of actuators 106 (four in the example of FIG. 22) are formed integrally. The actuator 106 shown in FIG. 23 is manufactured by cutting the integrally molded product of the plurality of actuators shown in FIG. In the case where each of the piezoelectric elements of the plurality of integrally formed actuators 106 shown in FIG.
Can be manufactured.
By integrally forming the plurality of actuators 106, the plurality of actuators can be manufactured efficiently at the same time, and handling during transportation becomes easy.

The actuator 106 includes a thin plate or vibration plate 176, a substrate 178, an elastic wave generating means or a piezoelectric element 17.
4, a terminal forming member or upper electrode terminal 168 and a terminal forming member or lower electrode terminal 170; Piezoelectric element 17
4 includes a piezoelectric diaphragm or piezoelectric layer 160, an upper or upper electrode 164, and a lower or lower electrode 166. A vibration plate 176 is formed on the upper surface of the substrate 178, and the vibration plate 17
6, a lower electrode 166 is formed. On the upper surface of the lower electrode 166, a piezoelectric layer 160 is formed.
An upper electrode 164 is formed on the upper surface of 60. Therefore, the main part of the piezoelectric layer 160 is formed so as to be sandwiched from above and below by the main part of the upper electrode 164 and the main part of the lower electrode 166.

A plurality (4 in the example of FIG. 22)
) Of piezoelectric elements 174 are formed. Diaphragm 176
The lower electrode 166 is formed on the surface of the piezoelectric layer 160, the piezoelectric layer 160 is formed on the surface of the lower electrode 166, and the upper electrode 164 is formed on the upper surface of the piezoelectric layer 160. An upper electrode terminal 168 and a lower electrode terminal 170 are formed at ends of the upper electrode 164 and the lower electrode 166. Four actuators 106
Are cut separately and used individually.

FIG. 23 shows a cross section of a part of the actuator 106 shown in FIG.

FIG. 24 shows the entire cross section of the actuator 106 shown in FIG. Piezoelectric element 17 on substrate 178
A through hole 178a is formed on the surface facing 4. The through hole 178a is sealed by the diaphragm 176. The vibration plate 176 is formed of a material having electrical insulation such as alumina or zirconia and capable of being elastically deformed. A piezoelectric element 174 is formed on the vibration plate 176 so as to face the through hole 178a. The lower electrode 166 is formed on the surface of the diaphragm 176 so as to extend in one direction from the region of the through hole 178a, to the left in FIG. The upper electrode 164 is formed on the surface of the piezoelectric layer 160 so as to extend from the region of the through hole 178a in the direction opposite to the lower electrode, and to the right in FIG. Upper electrode terminal 16
8 and the lower electrode terminal 170 are connected to the auxiliary electrode 172, respectively.
And on the upper surface of the lower electrode 166. The lower electrode terminal 170 is in electrical contact with the lower electrode 166, and the upper electrode terminal 168 is connected to the upper electrode 164 via the auxiliary electrode 172.
The piezoelectric element and the actuator 106
Exchanges signals with external devices. Upper electrode terminal 1
The lower electrode terminal 68 and the lower electrode terminal 170 have a height equal to or higher than the height of the piezoelectric element including the electrode and the piezoelectric layer.

FIG. 25 shows a method of manufacturing the actuator 106 shown in FIG. First, Green Sheet 940
Through holes 940 using press or laser processing
Perforate a. The green sheet 940 is the substrate 1 after firing.
It will be 78. The green sheet 940 is formed of a material such as ceramic. Next, the green sheet 941 is laminated on the surface of the green sheet 940. Green sheet 94
1 becomes the diaphragm 176 after firing. Green sheet 9
41 is formed of a material such as zirconia oxide. next,
The conductive layer 942 and the piezoelectric layer 1 on the surface of the green sheet 941
60, and a conductive layer 944 are sequentially formed by a method such as pressure film printing. The conductive layer 942 will later become the lower electrode 166, and the conductive layer 944 will later become the upper electrode 164. Next, the formed green sheet 940, green sheet 941, conductive layer 942, piezoelectric layer 160, and conductive layer 944 are dried and fired. The spacer members 947 and 948 raise the heights of the upper electrode terminal 168 and the lower electrode terminal 170 to be higher than the piezoelectric element. The spacer members 947 and 948 are
The same material as the green sheets 940 and 941 is printed or the green sheets are laminated. The upper electrode terminal 16 made of a noble metal is formed by the spacer members 947 and 948.
8 and the lower electrode terminal 170 require less material,
Since the thickness of the upper electrode terminal 168 and the lower electrode terminal 170 can be reduced, the upper electrode terminal 168 and the lower electrode terminal 1
70 can be printed with high accuracy, and the height can be further stabilized.

When the connection portion 944 'with the conductive layer 944 and the spacer members 947 and 948 are formed at the same time when the conductive layer 942 is formed, the upper electrode terminal 168 and the lower electrode terminal 170 can be easily formed or firmly fixed. Can be. Finally, upper electrode terminals 168 and lower electrode terminals 170 are formed in end regions of the conductive layers 942 and 944. When forming the upper electrode terminal 168 and the lower electrode terminal 170, the upper electrode terminal 168 and the lower electrode terminal 170 are formed.
Is formed so as to be electrically connected to the piezoelectric layer 160. In this embodiment, the through-hole 940a is formed as shown in FIG.
It is preferably an elongated hole as shown in FIG. Through hole 94
By making the major axis of Oa perpendicular to the liquid surface of the ink, or by tilting it in the direction perpendicular to the liquid level of the ink, the through hole 940a extends from one end to the other end of the major axis of the long hole. When the ink level is present, a change in the amount of ink in the ink cartridge can be detected. Therefore,
The longer the long diameter of the long hole, the larger the range of the amount of ink that can be detected by the actuator 106. In addition, as the major axis of the long hole is longer, the actuator 106 can detect a process in which the amount of ink or the remaining amount of ink gradually changes.

FIG. 26 shows still another embodiment of the ink cartridge to which the present invention is applied. FIG. 26 (A)
Is a part of the sectional view of the bottom of the ink cartridge according to the present embodiment. The ink cartridge according to the present embodiment includes:
There is a through hole 1c in the side wall of the container 1 for storing ink.
The through hole 1c is closed by the actuator 650 to form an ink reservoir.

FIG. 26 (B) shows a detailed cross section of the actuator 650 and the through hole 1c shown in FIG. 26 (A). FIG. 26C shows a plane of the actuator 650 and the through hole 1c shown in FIG. 26B. The actuator 650 has the diaphragm 72 and the piezoelectric element 73 fixed to the diaphragm 72. The actuator 650 is fixed to the side wall of the container 1 so that the piezoelectric element 73 faces the through hole 1c via the vibration plate 72 and the substrate 71. The diaphragm 72 is elastically deformable and has ink resistance.

In the case of this embodiment, the ink level is
When passing through the diameter x of c, the amplitude and frequency of the back electromotive force generated by the residual vibration in the vibration region of the actuator 650 change. Therefore, by detecting the change in the amplitude or the frequency, the liquid level of the ink can be detected. Also, by increasing the diameter x of the through hole 1c,
The width of the ink amount that can be detected by the actuator 650 can be increased. Further, by increasing the diameter x of the through hole 1c, the actuator 650 can detect a process in which the amount of ink or the remaining amount of ink gradually changes.

FIG. 27 is a perspective view showing another embodiment of the actuator. The actuator 660 has a packing 76 outside the through hole 1c of the substrate or the mounting plate 78 that constitutes the actuator 660. A caulking hole 77 is formed on the outer periphery of the actuator 660. The actuator 660 is fixed to the container 1 by swaging through the swaging hole 77.

FIGS. 28A and 28B are perspective views showing still another embodiment of the actuator. In the present embodiment, the actuator 670 is connected to the recess forming substrate 80.
And a piezoelectric element 82. A concave portion 81 is formed on one surface of the concave portion forming substrate 80 by a method such as etching, and a piezoelectric element 82 is mounted on the other surface. The bottom of the recess 81 in the recess forming substrate 80 functions as a vibration region. Therefore, the vibration region of the actuator 670 is defined by the periphery of the concave portion 81. The actuator 670 is the same as the actuator 1 according to the embodiment of FIG.
06, it is similar to the structure in which the substrate 178 and the diaphragm 176 are integrally formed. Therefore, the manufacturing process when manufacturing the ink cartridge can be shortened, and the cost is reduced. The actuator 670 has a size that can be embedded in the through hole 1c provided in the container 1.
Thereby, the concave portion 81 can also function as a cavity. The actuator 106 according to the embodiment in FIG. 18 is replaced with the actuator 67 according to the embodiment in FIG.
Similarly to the case of 0, it may be formed so that it can be embedded in the through hole 1c.

FIG. 29 is a perspective view showing a structure in which the actuator 106 is integrally formed as the mounting module body 100. The module body 100 is mounted at a predetermined position of the container 1 of the ink cartridge. Module body 100
Is configured to detect a consumption state of the liquid in the container 1 by detecting at least a change in acoustic impedance in the ink liquid. The module 100 of the present embodiment has a liquid container mounting portion 101 for mounting the actuator 106 to the container 1. The liquid container mounting portion 101 has a structure in which a cylindrical portion 116 containing an actuator 106 oscillated by a drive signal is mounted on a base 102 having a substantially rectangular plane. Module body 100
Is configured such that the actuator 106 of the module 100 cannot be contacted from the outside when the cartridge is mounted on the ink cartridge.
Can be protected from external contact. In addition, the tip side edge of the cylindrical portion 116 is rounded, so that it can be easily fitted when the cylindrical portion 116 is mounted in a hole formed in the ink cartridge.

FIG. 30 shows the module 1 shown in FIG.
FIG. 2 is an exploded view showing the configuration of the 00. Module body 100
The liquid container mounting portion 101 made of resin and the plate 1
10 and a piezoelectric device mounting portion 105 having a concave portion 113. Further, the module body 100 includes lead wires 104a and 104b, an actuator 106, and a film 108. Preferably, plate 110
Is formed from a material that is not easily rusted, such as stainless steel or a stainless alloy. The cylindrical portion 116 and the base 102 included in the liquid container mounting portion 101 are formed with an opening 114 at the center so as to accommodate the lead wires 104a and 104b, so that the actuator 106, the film 108, and the plate 110 can be accommodated. A recess 113 is formed. The actuator 106 is joined to the plate 110 via the film 108, and the plate 110 and the actuator 106 are fixed to the liquid container mounting portion 101. Therefore, the lead wires 104a and 104b, the actuator 106, the film 108 and the plate 11
0 is integrally attached to the liquid container attaching portion 101. Lead wires 104a and 104b couple to the upper and lower electrodes of actuator 106, respectively, to transmit drive signals to the piezoelectric layer while the actuator 10
The signal of the resonance frequency detected by 6 is transmitted to a recording device or the like. The actuator 106 oscillates temporarily based on the drive signal transmitted from the lead wires 104a and 104b. The actuator 106 undergoes residual vibration after oscillation, and generates a back electromotive force by the vibration. At this time, by detecting the oscillation period of the back electromotive force waveform,
The resonance frequency corresponding to the consumption state of the liquid in the liquid container can be detected. The film 108 bonds the actuator 106 and the plate 110 to make the actuator liquid-tight. The film 108 is preferably formed of a polyolefin or the like, and is preferably bonded by heat fusion.

The plate 110 has a circular shape.
The second opening 114 is formed in a cylindrical shape. The actuator 106 and the film 108 are formed in a rectangular shape. The lead wire 104, the actuator 106, the film 108, and the plate 110 may be detachable from the base 102. The base 102, the lead wires 104, the actuator 106, the film 108, and the plate 110 are symmetrically arranged with respect to the central axis of the module 100. Further, the centers of the base 102, the actuator 106, the film 108, and the plate 110 are disposed substantially on the central axis of the module 100.

The area of the opening 114 of the base 102 is formed to be larger than the area of the vibration region of the actuator 106. Actuator 10 at the center of plate 110
A through hole 112 is formed at a position facing the vibrating portion of No. 6. As shown in FIGS. 18 and 19, a cavity 162 is formed in the actuator 106, and the through hole 112 and the cavity 162 together form an ink reservoir. The thickness of the plate 110 is preferably smaller than the diameter of the through hole 112 in order to reduce the influence of the residual ink. For example, the depth of the through hole 112 is one third of its diameter.
The size is preferably as follows. The through hole 112 is
It has a substantially perfect circular shape symmetric with respect to the central axis of the module body 100. The area of the through hole 112 is larger than the opening area of the cavity 162 of the actuator 106.
The periphery of the cross section of the through hole 112 may be tapered or stepped. The module 100 is mounted on the side, top, or bottom of the container 1 so that the through holes 112 face the inside of the container 1. When the ink is consumed and the ink around the actuator 106 runs out, the resonance frequency of the actuator 106 greatly changes, so that a change in the ink level can be detected.

FIG. 31 is a perspective view showing another embodiment of the module body. Module body 400 of the present embodiment
In the figure, a piezoelectric device mounting portion 405 is formed on a liquid container mounting portion 401. In the liquid container mounting portion 401, a columnar column portion 403 is formed on a base 402 on a square whose plane is almost rounded. Further, the piezoelectric device mounting portion 405 includes a plate-shaped element 406 standing on the cylindrical portion 403 and a concave portion 41.
3 inclusive. The recess 41 provided on the side surface of the plate element 406
An actuator 106 is disposed at 3. Note that the tip of the plate-shaped element 406 is chamfered at a predetermined angle so that it can be easily fitted into a hole formed in the ink cartridge.

FIG. 32 shows the module 4 shown in FIG.
FIG. 2 is an exploded perspective view showing the configuration of the 00. Similar to the module 100 shown in FIG. 29, the module 400 includes a liquid container mounting portion 401 and a piezoelectric device mounting portion 405. The liquid container mounting portion 401 includes a base 402 and a cylindrical portion 4.
03, and the piezoelectric device mounting portion 405 has a plate-shaped element 406 and a concave portion 413. The actuator 106 is fixed to the concave portion 413 by being joined to the plate 410. The module 400 includes lead wires 404a and 404
b, the actuator 106, and the film 408.

According to the present embodiment, the plate 410 has a rectangular shape, and the opening 414 provided in the plate-like element 406 is provided.
Is formed in a rectangular shape. The lead wires 404a and 404b, the actuator 106, the film 408, and the plate 410 may be configured to be detachable from the base 402. Actuator 106, film 40
8 and the plate 410 are symmetrically arranged with respect to a central axis extending through the center of the opening 414 and extending in a direction perpendicular to the plane of the opening 414. Further, the centers of the actuator 406, the film 408, and the plate 410 are disposed substantially on the central axis of the opening 414.

The area of the through hole 412 provided at the center of the plate 410 is
62 are formed larger than the area of the opening. The cavity 162 and the through hole 412 of the actuator 106 together form an ink reservoir. The thickness of the plate 410 is smaller than the diameter of the through hole 412, for example, the thickness of the through hole 41.
It is preferable to set the size to one third or less of the diameter of 2. The through hole 412 has a substantially perfect circular shape symmetric with respect to the central axis of the module 400. The periphery of the cross section of the through hole 412 may be tapered or stepped. The module 400 can be mounted on the bottom of the container 1 so that the through hole 412 is arranged inside the container 1. Since the actuator 106 is disposed in the container 1 so as to extend in the vertical direction, the height of the base 402 is changed to change the height at which the actuator 106 is disposed in the container 1 so that the setting of the ink end point can be performed. Can be changed easily.

FIG. 33 shows still another embodiment of the module. Similar to the module 100 shown in FIG. 29, the module 500 shown in FIG. 33 includes a liquid container mounting portion 501 having a base 502 and a column 503. The module 500 further includes lead wires 504a and 504b, an actuator 106, a film 508, and a plate 510. Liquid container mounting part 50
An opening 514 is formed in the center of the base 502 included in 1 to accommodate the lead wires 504a and 504b, and a recess 513 is formed to accommodate the actuator 106, the film 508, and the plate 510. The actuator 106 is fixed to the piezoelectric device mounting portion 505 via the plate 510. Therefore, the lead wires 504a and 504b, the actuator 106, the film 508, and the plate 510 are connected to the liquid container mounting portion 5
01 is integrally attached. In the module body 500 of the present embodiment, a cylindrical portion 503 whose upper surface is oblique in the vertical direction is formed on a base having a square shape with a substantially round corner. The actuator 106 is disposed on a concave portion 513 provided obliquely in the vertical direction on the upper surface of the columnar portion 503.

The tip of the module 500 is inclined, and the actuator 106 is mounted on the inclined surface. Therefore, when the module 500 is mounted on the bottom or the side of the container 1, the actuator 106 is inclined with respect to the vertical direction of the container 1. The inclination angle of the tip of the module 500 is approximately 30 ° to 60 ° in view of the detection performance.
It is desirable to be between.

The module 500 includes the actuator 1
06 is mounted on the bottom or side of the container 1 so as to be placed in the container 1. When the module 500 is mounted on the side of the container 1, the actuator 106 is attached to the container 1 so as to face the upper side, the lower side, or the side of the container 1 while being inclined. On the other hand, when the module 500 is mounted on the bottom of the container 1, the actuator 10
6 is preferably attached to the container 1 so as to face the ink supply port side of the container 1 while being inclined.

The through-hole 11 shown in FIGS.
As shown in FIG. 25, the vibration regions of the actuators 2, 412 and the actuator 106, and the vibration region of the module 500 may be formed into a long circle having a long diameter. By making the major axes of the through-holes 112, 412, the vibrating region of the actuator 106, and the vibrating region of the module 500 perpendicular to the liquid surface of the ink, or by inclining in the direction perpendicular to the liquid surface of the ink. A change in the amount of ink in the ink cartridge is detected when there is a water level between one end and the other end of the long hole of the through hole 112, 412, the vibration region of the actuator 106, or the vibration region of the module 500. it can. Therefore, the longer the major axis of the long hole, the larger the range of the amount of ink that can be detected.

The shapes of the through-holes 112 and 412, the vibrating area of the actuator 106, and the vibrating area of the module 500 are not limited to circular shapes. Therefore, it may be a rectangle having a long diameter, a polygon, or an elongated groove.

FIG. 34 shows the module 1 shown in FIG.
FIG. 4 is a cross-sectional view near the bottom of the ink container when 00 is mounted on the container 1. FIG. 34 is exaggerated in comparison with FIG. 29 in order to cooperate that the vibrating part of the actuator 106 is long in the direction perpendicular to the ink surface.
The module 100 is mounted so as to penetrate the side wall of the container 1. An O-ring 365 is provided on the joint surface between the side wall of the container 1 and the module 100 to keep the module 100 and the container 1 liquid-tight. The module 100 preferably has a columnar portion as described with reference to FIG. 32 so that sealing can be performed with an O-ring. When the tip of the module 100 is inserted into the container 1, the ink in the container 1 comes into contact with the actuator 106 through the through hole 112 of the plate 110. Actuator 1
Since the resonance frequency of the residual vibration of the actuator 106 differs depending on whether the periphery of the vibrating portion 06 is a liquid or a gas, the ink consumption state can be detected using the module 100. In addition, not limited to the module body 100, FIG.
The module 400 shown in FIG. 1 or the module 500 shown in FIG. 33 may be mounted on the container 1 to detect the presence or absence of ink.

FIG. 35 shows a cross section of the ink cartridge of this embodiment cut in the longitudinal direction or the longitudinal direction.
The packing 4 and the valve 6 are provided in the ink supply port 2. The packing 4 is engaged in a liquid-tight manner with the ink supply needle 32 communicating with the recording head 31, as in FIG. Valve 6
Is always in elastic contact with the packing 4 by the spring 5. When the ink supply needle 32 is inserted, the valve 6 is pushed by the ink supply needle to open the ink flow path. The container 1 has a semiconductor storage means 7 at an upper portion in which information on the ink in the ink cartridge is stored.

The ink cartridge in this embodiment is
A container 1 for storing ink, an ink supply port 2 for supplying ink, and an actuator 106 for continuously detecting the consumption state of the liquid in the container 1 are provided. Actuator 1
Reference numeral 06 denotes an elongated member extending in a direction perpendicular to the liquid level of the liquid in the container 1. As the actuator 106 is formed in a long shape, the actuator 106 is formed into a long shape extending in a direction perpendicular to the liquid surface of the liquid in the container 1 in the vibration region of the actuator 106.

[0169] Of the side walls of the container 1, a supply port side wall 1010 provided with the ink supply port 2 is provided with a long opening perpendicular to the ink surface. The actuator 106 is provided so as to fit in an opening provided on the supply port side wall 1010 in a liquid-tight manner. Actuator 106
Is located near the ink supply port 2. The other end of the actuator 106 is connected to the supply port side wall 101.
It is positioned near the boundary between the supply port side wall 1010 and the upper surface 1020 which is adjacent to 0 and is upward with respect to the ink level. In this embodiment, the actuator 106 extends from the vicinity of the supply port 2 to the upper surface 1020. The length of the actuator 106 is the ink supply port 2
It is preferable that the length is at least half the length from the upper surface to the upper surface 1020. However, the length of the actuator 106 is not limited.

FIG. 36 shows a cross section of an ink cartridge according to another embodiment of the present embodiment, which is cut in the longitudinal direction or the longitudinal direction. The packing 4 and the valve 6 are provided in the ink supply port 2. The packing 4 is engaged in a liquid-tight manner with the ink supply needle 32 communicating with the recording head 31, as in FIG. The valve element 6 is always in elastic contact with the packing 4 by the spring 5. When the ink supply needle 32 is inserted, the valve 6 is pushed by the ink supply needle to open the ink flow path.
The container 1 has a semiconductor storage means 7 at an upper portion in which information on the ink in the ink cartridge is stored.

The ink cartridge in this embodiment is
A container 1 for storing ink, an ink supply port 2 for supplying ink, and an actuator 106 for continuously detecting the consumption state of the liquid in the container 1 are provided. Actuator 1
Reference numeral 06 denotes an elongated member extending in a direction perpendicular to the liquid level of the liquid in the container 1.

[0172] Of the side walls of the container 1, the opposing side wall 1 opposing the supply port side wall 1010 where the ink supply port 2 is provided.
030 is provided with an opening that is long perpendicular to the liquid surface of the ink. The actuator 106 is mounted on the opposite side wall 10.
30 is provided so as to be fitted in a liquid-tight manner in the opening provided in the opening 30. One end of the actuator 106 is connected to the opposite side wall 1030
Bottom surface 1a which is adjacent to and below the ink level
And near the boundary with the opposing side wall 1030. The other end of the actuator 106 is
Upper surface 1 adjacent to 0 and above the ink level
020 and the side wall 1030. In this embodiment, the actuator 10
6 extends from the vicinity of the bottom surface 1a to the vicinity of the upper surface 1020. The length of the actuator 106 is preferably at least half the length from the bottom surface 1a to the top surface 1020. However, the length of the actuator 106 is not limited.

In FIGS. 35 and 36, the actuator 106 is provided on only one of the supply port side wall 1010 and the opposing side wall 1030. However, both the supply port side wall 1010 and the opposing side wall 1030 are provided. Is also good.

FIG. 37 shows a cross section of the ink cartridge according to the present embodiment in the short direction or the width direction of the ink cartridge. In this embodiment, the actuator 10
Reference numeral 6 denotes one of the interposed side walls 1020a and 1020b interposed between a supply port side wall (not shown) in which the ink supply port 2 is provided and an opposing side wall facing the supply port side wall. Be deployed. One end of the actuator 106 is positioned near the boundary between the bottom surface 1a and the intervening side wall 1020a. The other end of the actuator 106
It is provided at a position beyond the middle between the bottom surface 1a and the top surface 1020 facing the bottom surface 1a. In this embodiment, the actuator 106 moves from the vicinity of the bottom surface 1a to the top surface 10a.
It extends to a position beyond the middle between 20 and the bottom surface 1a.
However, the length of the actuator 106 is not specified. Therefore, the actuator 106 may extend from near the bottom surface 1a to near the top surface 1020. However, the length of the actuator 106 is preferably at least half the length from the bottom surface 1a to the top surface 1020.
The actuator 106 of FIG. 37 may be provided on the side wall 1020b.

In FIG. 37, the actuator 10
6 is provided on only one of the intervening side walls 1020a, but both may be provided on both the intervening side walls 1020a and 1020b.

In FIGS. 35 to 37, the ink supply port 2 is provided so as to supply the ink K in a horizontal direction with respect to the liquid surface of the ink K. However, the direction of the ink supply port 2 is not limited. Therefore, the ink supply port 2
May be arranged so as to supply the ink K in a direction perpendicular to the liquid level of the ink K.

FIG. 38 is a sectional view of an ink cartridge in a case where the ink supply port 2 is provided so as to supply the ink K in a direction perpendicular to the liquid surface of the ink K. The actuator 106 is provided on a supply port side wall 1021d on the ink supply port 2 side among the side walls adjacent to the bottom surface 1011 where the ink supply port 2 is provided. One end of the actuator 106 is positioned near the ink supply port 2. The other end of the actuator 106 is positioned near the boundary between the upper surface 1031 facing the bottom surface 1011 and the supply port side wall 1021d. Therefore, the actuator 106 extends from the vicinity of the ink supply port 2 to the upper surface 1031. Actuator 10
6 does not always need to extend from the vicinity of the ink supply port 2 to the upper surface 1031. However, it is preferable that the actuator 106d has a length that is at least half the length from the ink supply port 2 to the upper surface 1031.

FIG. 39 is a sectional view of an ink cartridge in a case where the ink supply port 2 is provided so as to supply the ink K in a direction perpendicular to the liquid surface of the ink K. The actuator 106 is provided on an opposite side wall 1021c adjacent to the bottom surface 1011 having the ink supply port 2 and facing the supply port side wall 1021d. One end of the actuator 106 is connected to the opposite side wall 1021c and the bottom surface 101c.
11 is located in the vicinity of the boundary. The other end of the actuator 106 is connected to the upper surface 1 facing the bottom surface 1011.
031 and the boundary between the opposing side wall 1021c. Accordingly, the actuator 106 is
11 to the upper surface 1031. The actuator 106 is not limited to extending from the bottom surface 1011 to the top surface 1031. However, the actuator 106
Preferably has a length of at least half the length from the bottom surface 1011 to the top surface 1031.

As shown in the embodiment of FIGS. 35 to 39, by disposing the actuator 106, the actuator 106 can move the ink K from the time when the ink K is filled in the container 1 to the ink end or the ink near end. Consumption state can be accurately detected. Therefore, even if the ink remains sufficiently in the ink cartridge, the actuator 106 does not erroneously detect the ink end or the ink near end. Conversely, the actuator 106 does not erroneously detect that the ink remains sufficiently despite the ink end or the ink near end. Thereby, printing failure does not occur.

FIG. 40 is a sectional view of another embodiment of the ink cartridge in the case where the ink supply port 2 is provided so as to supply the ink K in a direction perpendicular to the liquid surface of the ink K. . The ink supply port 2 has a hollow cylindrical shape. The ink supply port 2 is provided with a supply port valve 2000 formed of an elastic body, for example, rubber. The actuator 106 is provided on the inner wall surface of the hollow cylindrical ink supply port 2. The supply port valve 2000 is liquid-tightly attached to the ink supply port 2 so as to seal the ink in the container 1 when the ink cartridge is not used. On the other hand, an ink supply needle (not shown) penetrates the supply port valve 2000 and is inserted into the ink supply port 2 to supply ink to a recording head (not shown) provided in the ink jet recording apparatus. Since the actuator 106 is provided on the inner wall surface of the ink supply port 2, the actuator 106 detects the liquid level of the ink after the liquid level of the ink reaches the substantially inner end of the ink supply port 2 of the container 1. Can be. Thereby, the actuator 106
Since the liquid level of the ink is detected at a position closer to the ink end, the ink in the ink cartridge can be consumed without waste.

FIGS. 41 to 43 show an embodiment of an ink cartridge containing a plurality of types of ink. Container 8
Is divided into three ink storage chambers 9, 10, and 11 by a wall. In each of the ink storage chambers, ink supply ports 12, 13, and 14 are formed. In each of the ink storage chambers 9, 10, and 11, an actuator 106 is attached so as to come into contact with the ink in each ink storage chamber via an opening provided in the container 8.

The container 8 has at least two ink storage chambers 9, 10, and 11 in which different types of ink are stored. Ink supply ports 12, 13, and 14 provided in the respective ink storage chambers 9, 10, and 11
Supplies ink from each of the ink storage chambers 9, 10, and 11 to the recording head.

In FIG. 41, the actuator 106 is provided on the supply port surface 1013 where the ink supply port 2 is provided. One ends of the actuators 106 are located near the ink supply ports 12, 13, and 14, respectively. The other end of the actuator 106 is positioned near an upper surface (not shown) opposite to the bottom surface 8a. In this embodiment, the actuator 106 is connected to the ink supply port 1.
It extends from the vicinity of 2, 13, and 14 to the upper surface. The length of the actuator 106 is not limited to the length from the vicinity of the supply port 2 to the upper surface. However, the actuator 106
Is preferably at least half the length from the ink supply port 2 to the upper surface.

FIG. 42 is a perspective view of the ink cartridge viewed from the side of the facing surface 1050 facing the supply port surface 1013 where the ink supply port 2 is provided. Actuator 1
Reference numeral 06 is provided on a facing surface 1050 facing the supply port surface 1013. One ends of the actuators 106 are respectively positioned near the bottom surface 8a. Actuator 1
The other end of 06 is located near an upper surface (not shown) opposite to the bottom surface 8a. In this embodiment, the actuator 106 extends from the vicinity of the bottom surface 8a to the top surface. The length of the actuator 106 is not limited to the length from the vicinity of the bottom surface 8a to the top surface. However, the length of the actuator 106 is preferably at least half the length from the bottom surface 8a to the top surface.

In FIG. 43, the actuator 106 is provided on the bottom surface 8a. The bottom surface 8a has an inclined portion 1025 that is inclined with respect to the liquid surface of the liquid. Actuator 1
Reference numeral 06 is provided in each of the inclined portions 1025 of the ink storage chambers 9, 10, and 11. Actuator 106
Extends from one end of the inclined portion 1025 on the ink supply port 12, 13, 14 side to the other end of the inclined portion 1025. Since the actuator 106 is inclined with respect to the liquid level of the ink, the consumption state of the ink can be detected by detecting that the water level of the ink gradually changes. In this embodiment, the actuator 106 has a length from one end of the inclined portion 1025 on the ink supply port 12, 13, 14 side to the other end of the inclined portion 1025. But,
The length of the actuator 106 is not limited.

The actuator 106 shown in FIGS. 41 to 43 is used.
Of these, one of the actuators 106 may be provided in each of the ink storage chambers 9, 10, and 11. Therefore, the actuator 106 shown in FIGS.
And one actuator 106 can be provided in each of the ink storage chambers 11, 12, and 13. For example, the actuator 1 of FIG.
06 may be provided, and the actuator 106 of FIG. 41 may be provided in the ink storage chamber 10. Actuator 1
06 may be provided in each of the ink storage chambers 9, 10, and 11. This can prevent erroneous detection of the ink consumption state in the ink cartridge.

FIG. 44 shows still another embodiment of the ink cartridge 180. 44A is a cross-sectional view of the ink cartridge 180C, FIG. 44B is an enlarged cross-sectional view of the side wall 194b of the ink cartridge 180C shown in FIG. 44A, and FIG. 44C is a front view thereof. It is a perspective view. The ink cartridge 180C has a circuit board 610 on which the semiconductor storage means 7 and the actuator 106 are the same.
Is formed on. As shown in FIGS. 44B and 44C, the semiconductor storage means 7 is formed above the circuit board 610, and the actuator 106 is formed below the semiconductor storage means 7 on the same circuit board 610. O-ring 614 is shaped to surround the periphery of actuator 106.
Is formed on the side wall 194b. A plurality of caulking portions 616 for joining the circuit board 610 to the ink container 194 are formed on the side wall 194b. By bonding the circuit board 610 to the ink container 194 by the caulking portion 616 and pressing the odd-shaped O-ring 614 against the circuit board 610,
The outside and inside of the ink cartridge are kept liquid-tight, while allowing the vibration area of the actuator 106 to come into contact with the ink.

A terminal 612 is formed in the semiconductor storage means 7 and in the vicinity of the semiconductor storage means 7. The terminal 612 exchanges signals between the semiconductor storage means 7 and the outside such as an ink jet storage device. The semiconductor storage means 7 may be constituted by a rewritable semiconductor memory such as an EEPROM. Since the semiconductor storage means 7 and the actuator 106 are formed on the same circuit board 610, only one mounting step is required when mounting the actuator 106 and the semiconductor storage means 7 on the ink cartridge 180C. Further, the working process at the time of manufacturing and recycling the ink cartridge 180C is simplified. Further, since the number of parts is reduced, the ink cartridge 180
The manufacturing cost of C can be reduced.

[0189] The actuator 106 detects the consumption state of the ink in the container 194. The semiconductor storage unit 7 stores ink information such as the remaining amount of ink detected by the actuator 106. That is, the semiconductor storage means 7 stores information on characteristic parameters such as characteristics of the ink and the ink cartridge used for detection. When the ink in the container 194 is full beforehand,
That is, the resonance frequency when the container 194 is filled or at the end, that is, when the ink in the container 194 is consumed, is stored as one of the characteristic parameters.
The resonance frequency when the ink in the container 194 is full or in the end state may be stored when the container 194 is first attached to the inkjet recording apparatus. Further, the resonance frequency when the ink in the container 194 is full or in the end state is equal to the resonance frequency of the container 1.
94 may be stored during manufacture. The resonance frequency when the ink in the container 194 is full or end is stored in advance in the semiconductor storage means 7, and the data of the resonance frequency is read out on the ink jet recording apparatus side, so that the variation in detecting the remaining ink amount can be corrected. Therefore, it is possible to accurately detect that the remaining amount of ink has decreased to the reference value.

FIG. 45 shows still another embodiment of the ink cartridge 180. In the ink cartridge 180E of this embodiment, an actuator 606 that is long in the vertical direction is mounted on the side wall 194b of the container 194. Preferably, the length of the actuator 606 is at least half of the height of the side wall 194b, and the length of the actuator 606 is approximately from the upper end to the lower end of the side wall 194b. The change in the remaining amount of ink in the container 194 can be continuously detected by the vertically long actuator 606.

FIG. 46 shows still another embodiment of the ink cartridge using the actuator 106. FIG.
The ink cartridge 220A of (A) is a first partition 2 extending downward from the upper surface of the ink cartridge 220A.
22. Since a predetermined space is provided between the lower end of the first partition wall 222 and the bottom surface of the ink cartridge 220A, ink can flow into the ink supply port 230 through the bottom surface of the ink cartridge 220A. On the ink supply port 230 side from the first partition 222, a second partition 224 is formed so as to extend above the bottom surface of the ink cartridge 220A. Since a predetermined interval is provided between the upper end of the second partition 224 and the upper surface of the ink cartridge 220A, the ink can flow into the ink supply port 230 through the upper surface of the ink cartridge 220A.

The first partition 222 forms a first storage chamber 225 a at the back of the first partition 222 when viewed from the ink supply port 230. On the other hand, the second partition 224 causes the second partition 222 to be viewed from the ink supply port 230.
A second storage chamber 225b is formed in front of the second storage chamber 225b. The capacity of the first storage chamber 225a is larger than the capacity of the second storage chamber 225b. Capillary paths 227 are formed between the first partition wall 222 and the second partition wall 224 by providing an interval sufficient to cause capillary action. Therefore, the first
Is collected in the capillary channel 227 by the capillary force of the capillary channel 227. Therefore, it is possible to prevent gas and bubbles from entering the second storage chamber 225b. Further, the water level of the ink in the second storage chamber 225b can be stably gradually lowered. Ink supply port 23
0, the first accommodation room 225a is the second accommodation room 2
25b, the first storage chamber 22
After the ink in 5a is consumed, the ink in the second storage chamber 225b is consumed.

The actuator 106 is provided on the side wall of the ink cartridge 220A on the ink supply port 230 side, that is, on the side wall of the second storage chamber 225b on the ink supply port 230 side.
Is installed. The actuator 106 detects a state of ink consumption in the second storage chamber 225b. The actuator 106 is mounted on a side wall of the second storage chamber 225b. The actuator 106 is long in a direction perpendicular to the ink level. Therefore, the actuator 106 can detect that the liquid level of the ink gradually decreases. Further, the actuator 106 is connected to the second accommodation chamber 225.
By changing the height attached to the side wall of b and the length of the actuator 106 in the direction perpendicular to the ink surface, it is possible to determine the remaining amount of the ink at the end of the ink.
It is possible to freely set a change in the amount of ink from which point in time to which point. Capillary channel 22
7, the first accommodation room 225a to the second accommodation room 22
By supplying the ink to the ink cartridge 5b, the actuator 106 is not affected by the ink sway caused by the sway of the ink cartridge 220A, so that the actuator 106 can reliably measure the remaining amount of the ink. Further, since the capillary channel 227 holds the ink, the ink is prevented from flowing backward from the second supply chamber 225b to the first storage chamber 225a.

On the upper surface of the ink cartridge 220A,
There is a vent 233 and a check valve 228 is provided.
The check valve 228 allows the ink cartridge 220A to roll when the ink cartridge 220A rolls.
A can be prevented from leaking outside. Furthermore, check valve 2
By disposing 28 on the upper surface of ink cartridge 220A, evaporation of ink from ink cartridge 220A can be prevented. When the ink in the ink cartridge 220A is consumed and the negative pressure in the ink cartridge 220A exceeds the pressure of the check valve 228, the check valve 228 opens, and air is sucked into the ink cartridge 220A.
Thereafter, the ink cartridge is closed to keep the pressure inside the ink cartridge 220A constant.

FIGS. 46 (C) and (D) show the check valve 228.
3 shows a cross section of the detail. The check valve 228 in FIG.
It has a valve 232 having vanes 232a formed of rubber. Vent hole 2 with the outside of ink cartridge 220
The ink cartridge 2 faces the blade 232a.
20. The blades 232a allow the ventilation holes 23
3 are opened and closed. The check valve 228 serves to reduce the amount of ink in the ink cartridge 220 and
When the negative pressure within zero exceeds the pressure of the check valve 228, the blade 23
2a opens inside the ink cartridge 220 and takes in external air into the ink cartridge 220. The check valve 228 in FIG. 46D includes a valve 232 and a spring 235 formed of rubber. When the negative pressure in the ink cartridge 220 exceeds the pressure of the check valve 228, the check valve 228 opens by pressing the spring 235, sucks external air into the ink cartridge 220, and then closes. Thus, the negative pressure in the ink cartridge 220 is kept constant.

The ink cartridge 220 shown in FIG.
B shows the first storage chamber 225 instead of providing the check valve 228 in the ink cartridge 220A of FIG.
The porous member 242 is arranged at a. Porous member 24
2 holds the ink in the ink cartridge 220B and prevents the ink from leaking out of the ink cartridge 220B when the ink cartridge 220B sways.

The actuator 106 is provided on the side wall of the ink cartridge 220B on the ink supply port 230 side, that is, on the side wall of the second storage chamber 225b on the ink supply port 230 side.
Is installed. The actuator 106 detects a state of ink consumption in the second storage chamber 225b. The actuator 106 is long in a direction perpendicular to the ink level. Therefore, the actuator 106 can detect that the liquid level of the ink gradually decreases. Further, by changing the height at which the actuator 106 is mounted on the side wall of the second storage chamber 225b and the length of the actuator 106 in the direction perpendicular to the ink surface, the remaining ink amount at any time can be reduced. , And from which point in time a change in the ink amount is detected can be set freely.

In the above description, the case where the actuator 106 is mounted on the ink cartridge or the carriage in the ink cartridge separate from the carriage mounted on the carriage has been described. However, the actuator is integrated with the carriage and mounted on the ink jet recording apparatus together with the carriage. The actuator 106 may be mounted on the ink tank to be used. Furthermore, through a tube or the like separate from the carriage,
The actuator 106 may be mounted on an off-carriage type ink tank that supplies ink to the carriage.
Furthermore, the actuator of the present invention may be mounted on an ink cartridge in which the recording head and the container are integrally exchangeable.

As described above, the present invention has been described using the embodiments. However, the technical scope of the present invention is not limited to the scope described in the above embodiments. Various changes or improvements can be added to the above embodiment. It should be noted that such modified or improved embodiments may be included in the technical scope of the present invention.
It is clear from the description of the claims.

[0200]

According to the liquid container and the module of the present invention, it is possible to provide a liquid container capable of accurately detecting the remaining amount of liquid and eliminating the need for a complicated sealing structure.

With the liquid container and the module of the present invention, the number of steps for manufacturing the liquid container is small, the manufacturing cost is low, and the amount of consumption of the liquid in the liquid container is continuously detected regardless of the type of liquid. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an embodiment of an ink cartridge for a single color, for example, a black ink.

FIG. 2 is a diagram illustrating an embodiment of an ink cartridge that stores a plurality of types of ink.

FIG. 3 is a diagram showing an embodiment of an ink jet recording apparatus suitable for the ink cartridge shown in FIGS. 1 and 2.

FIG. 4 is a view showing a detailed cross section of the sub tank unit 33.

FIG. 5 is a diagram showing a method of manufacturing the elastic wave generating means 3, 15, 16, and 17;

FIG. 6 is a view showing another embodiment of the elastic wave generating means 3 shown in FIG.

FIG. 7 is a view showing another embodiment of the ink cartridge of the present invention.

FIG. 8 is a view showing still another embodiment of the ink cartridge of the present invention.

FIG. 9 is a view showing still another embodiment of the ink cartridge of the present invention.

FIG. 10 is a view showing still another embodiment of the ink cartridge of the present invention.

FIG. 11 is a view showing still another embodiment of the ink cartridge of the present invention.

FIG. 12 is a view showing another embodiment of the ink cartridge shown in FIG. 11;

FIG. 13 is a diagram showing a cross section of an embodiment of the ink jet recording apparatus of the present invention.

FIG. 14 is a diagram showing an embodiment of an ink cartridge suitable for the recording apparatus shown in FIG.

FIG. 15 is a view showing another embodiment of the ink cartridge 272 of the present invention.

FIG. 16 is a view showing still another embodiment of the ink cartridge 272 and the ink jet recording apparatus of the present invention.

FIG. 17 is a view showing another embodiment of the ink cartridge 272 shown in FIG.

FIG. 18 is a diagram showing details of an actuator 106 and its periphery.

FIG. 19 is a diagram showing details of an actuator 106 and its periphery.

FIG. 20 is a diagram illustrating a relationship between ink density and a resonance frequency of ink detected by an actuator 106.

21 is a diagram showing a back electromotive force waveform of the actuator 106. FIG.

FIG. 22 is a view showing another embodiment of the actuator 106.

FIG. 23 is a view showing a cross section of a part of the actuator 106 shown in FIG. 22;

24 is a diagram showing a cross section of the entire actuator 106 shown in FIG. 22;

25 is a diagram illustrating a method of manufacturing the actuator 106 illustrated in FIG.

FIG. 26 is a view showing still another embodiment of the ink cartridge of the present invention.

FIG. 27 is a view showing another embodiment of the actuator 660.

FIG. 28 is a view showing still another embodiment of the actuator 670.

FIG. 29 is a perspective view showing the module body 100.

30 is an exploded view showing the configuration of the module 100 shown in FIG. 29.

FIG. 31 is a view showing another embodiment of the module body 100.

FIG. 32 is an exploded view showing a configuration of the module 100 shown in FIG. 31.

FIG. 33 is a view showing still another embodiment of the module body 100.

FIG. 34 shows a case where the module 100 shown in FIG.
FIG. 4 is a diagram showing an example of a cross section mounted on the horn.

FIG. 35 is a view illustrating a cross section of the ink cartridge according to the present embodiment cut in a longitudinal direction or a longitudinal direction.

FIG. 36 is a view illustrating a cross section of the ink cartridge according to the present embodiment cut in a longitudinal direction or a longitudinal direction.

FIG. 37 is a diagram illustrating a cross section of the ink cartridge according to the present embodiment in a lateral direction or a width direction of the ink cartridge.

FIG. 38 is a sectional view of the ink cartridge in a case where the ink supply port is provided so as to supply ink in a direction perpendicular to the liquid surface of the ink.

FIG. 39 is a cross-sectional view of the ink cartridge when the ink supply port is provided so as to supply the ink in a direction perpendicular to the ink surface.

FIG. 40 is a cross-sectional view of the ink cartridge in a case where the ink supply port is provided so as to supply ink in a direction perpendicular to the liquid surface of the ink.

FIG. 41 is a diagram illustrating an embodiment of an ink cartridge that stores a plurality of types of ink.

FIG. 42 is a diagram illustrating an embodiment of an ink cartridge that stores a plurality of types of ink.

FIG. 43 is a diagram illustrating an embodiment of an ink cartridge that stores a plurality of types of ink.

FIG. 44 is a view showing still another embodiment of the ink cartridge 180.

FIG. 45 is a view showing still another embodiment of the ink cartridge 180.

FIG. 46 is a view showing still another embodiment of the ink cartridge using the module body 100.

[Explanation of symbols]

1, 8, 194: Container 1a, 1011: Bottom surface 1b: Side wall 1c, 940a: Through hole 2, 12, 13, 14 ... Ink supply port 3, 15, 16, 17, 41, 42, 43, 44, 6
5, 66, 70 ... elastic wave generating means 4 ... packing 5 ... spring 6 ... valve element 7 ... semiconductor storage means 8 ... container 8a ... bottom surface 9, 10, 11 ... Ink storage chamber 20 ... Fixed substrates 21, 23 ... Conductive material layers 21a, 23a ... Connection terminals 22 ... Green sheet 30 ... Carriage 31 ... Recording head 32 ... Ink supply needle 33 ... Sub tank unit 34 ... Ink chamber 35 ... Ink supply path 36 ... Membrane valve 37 ... Filter 38 ... Valve 67 ... Plate 68 ... Float 71 ... Adhesive layers 80, 178 ... Substrates 73, 82, Piezoelectric vibrating plates 74, 75 ... Ink absorber 76 ... Packing 77 ... Crimping holes 81 ... Concave parts 100, 400, 500 , 700 ... Module 1 02: Base part 104, 362: Lead wire 106, 650, 660, 670: Actuator 108: Film 110: Plate 112: Cavity 113: Concave part 114: Opening 116: Column portion 160: Piezoelectric layer 162, 370: Cavity 164: Upper electrode 166: Lower electrode 168: Upper electrode terminal 170: Lower electrode terminal 172 ... Auxiliary electrode 174 Piezoelectric element 176 Vibrating plate 180 Ink cartridge 181 Air supply port 182 Ink introduction section 183 Ink introduction port 184 Valve section 185 ..Air inlet 186 ... Head plate 187 ... Ink supply port 188 ... Nozzle plate 189 ... Switching valve 190 ...・ Nozzle 192 ・ ・ ・ Wavebreak wall 194 ・ ・ ・ Container 194a ・ ・ ・ Bottom 194b ・ ・ ・ Side wall 194c ・ ・ ・ Top 212 212 Partition wall 213, 213a, 213b ・ ・ ・ Accommodation room 214 ・ ・ ・ Buffer 216 , 216a, 216b ... porous member 220 ... ink cartridge 222 ... first partition 224 ... second partition 225a ... first storage chamber 225b ... second storage chamber 227: Capillary channel 228: Check valve 230: Ink supply port 232: Valve 232a: Blade 233: Vent hole 235: Spring 242: Porous member 250 ..Carriage 252 Printhead 254 Ink supply needle 256 Subtank unit 258,258 'Projection 260,260' Elastic wave generating means 26 2 Ink chamber 264 Ink supply path 266 Membrane valve 268 Filter 270 Valve 272 Ink cartridge 274 Container 274a Bottom surface 274b Side surface 276: Ink supply port 278 ... Depression 280, 280 '... Gelling material 282 ... Packing 284 ... Spring 286 ... Valve 288 ... Semiconductor storage means 290 ... Container 290a ... Bottom surface 292,294,296 ... Ink chamber 298,300,302 ... Ink supply port 304,306,308 ... Gelling material 310,312,314 ... Recess 316 ... -Plate material 318 ... Float 402, 502 ... Base 403 ... Columnar base 404, 504 ... Lead wire 408, 508 ... Film 410 510: plate 413, 513: recess 414, 514: opening 600: mounting structure 606: actuator 610: substrate 612: terminal 940, 941: green sheet 942, 944: conductive layer 944 ': connection portion 947, 948: auxiliary conductive layer 1010, 1021: supply port side wall 1020, 1031: upper surface 1030: opposed side wall 2000: Supply port valve Δh1, Δh2: change in liquid level K: ink

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Minoru Usui 3-5-5 Yamato, Suwa-shi, Nagano F-term in Seiko Epson Corporation (reference) 2C056 EA29 EB20 EB50 KC05 KC22 KC30 2F014 AA07 AB02 AB03 FB01 GA05

Claims (19)

[Claims] 1. A container for storing a liquid, a liquid supply port for supplying the liquid, a base fixed to the container, and a vibrating plate having at least one end fixed to the base so as to be able to vibrate. And a piezoelectric device configured to continuously detect a consumption state of the liquid in the container. 2. The liquid container according to claim 1, wherein the piezoelectric device is an elongated member. 3. The liquid container according to claim 2, wherein the piezoelectric device is disposed in a direction perpendicular to a liquid level in the container. 4. The liquid container according to claim 1, wherein a vibration area of the vibration plate for detecting a liquid extends in a direction in which a liquid level in the container changes. 5. The liquid container according to claim 4, wherein one end of the vibration region extends to a bottom surface of the inner wall of the container below a liquid surface of the liquid. 6. The liquid container according to claim 5, wherein the other end of the vibration region extends to an upper surface of the inner wall of the container that is above a liquid surface of the liquid. 7. The vibrating region extends from an upper surface of the inner wall of the container above the liquid surface of the liquid to a bottom surface of the inner wall of the container below the liquid surface of the liquid. The liquid container according to claim 4, wherein the liquid container has a length equal to or longer than half of the length. 8. The liquid container according to claim 1, wherein the piezoelectric device or the vibration region is inclined with respect to a liquid level of the liquid in the container. 9. The container according to claim 8, wherein the container has an inclined surface inclined with respect to the liquid level of the liquid in the container, and the piezoelectric device is provided on the inclined surface. Liquid container. 10. The liquid supply port has an opening surface that opens in the direction of the inside of the container, and the vibration area is provided on a water level surface of the liquid surface when the liquid surface of the liquid reaches the opening surface. The liquid container according to claim 4, wherein one end of the liquid container is located. 11. The liquid container according to claim 4, wherein the piezoelectric device is provided on an inner wall surface of the hollow cylindrical liquid supply port. 12. The liquid container according to claim 1, wherein the piezoelectric device has a cavity that opens toward the inside of the container and contacts a liquid in the container. 13. The piezoelectric device according to claim 1, wherein the piezoelectric device further includes a vibrating portion that vibrates together with the vibrating plate, and one end and the other end of the vibrating portion are fixed to the base. Liquid container. 14. The liquid container according to claim 1, wherein the liquid comes into contact with only a vibration area of the vibration plate that detects the liquid. 15. The piezoelectric device according to claim 1, wherein the piezoelectric device has a vibrating portion that generates vibration, and detects a consumption state of the liquid based on a back electromotive force generated by residual vibration remaining in the vibrating portion. The liquid container according to claim 1. 16. The liquid according to claim 1, wherein the piezoelectric device detects at least an acoustic impedance of the liquid, and detects a consumption state of the liquid based on the acoustic impedance. container. 17. The liquid container according to claim 1, further comprising a storage unit capable of storing information on a consumption state of the liquid detected by the piezoelectric device. 18. The ink jet recording apparatus according to claim 1, which is mounted on an ink jet recording apparatus having a recording head for discharging ink droplets, and supplies the liquid in the container to the recording head. Liquid container. 19. The piezoelectric device according to claim 1, further comprising a mounting structure, wherein the piezoelectric device is disposed in the container via the mounting structure.
The liquid container according to any one of the above.