CN100371690C

CN100371690C - Liquid-detecting device and liquid container with the same

Info

Publication number: CN100371690C
Application number: CNB200480003893XA
Authority: CN
Inventors: 高桥智明; 片仓孝浩; 品田聪
Original assignee: Seiko Epson Corp
Current assignee: Seiko Epson Corp
Priority date: 2003-02-10
Filing date: 2004-02-10
Publication date: 2008-02-27
Anticipated expiration: 2024-02-10
Also published as: CN1748128A

Abstract

A first electrode (46) has a body portion (46a) covering substantially the whole of the area of a recess portion (43), and the body portion (46a) includes a cutout portion (46c). A piezoelectric layer (47) has a body portion (47a) with a diameter smaller than that of the recess portion (43), the entire part of the layer is within the recess portion area, and substantially the whole of the body portion (47a) except the portion corresponding to the cutout portion (46c) is layered over the first electrode (46). An auxiliary electrode (48) extends from the outside up to the inside of the recess portion area, and portion of the auxiliary electrode is positioned inside the cutout portion (46c) of the first electrode (46) and supports portion of the piezoelectric layer (47). A second electrode (49) has a body portion (49a) layered over the piezoelectric layer (47) and an extending portion (49b) extending from the body portion (49a) and connected inside the recess portion area to the auxiliary electrode (48). Condition of residual vibration of a vibrating portion of the liquid-detecting device can be easily and reliably detected, and cracks in the piezoelectric layer can be prevented from occurring.

Description

Liquid-detecting and be furnished with the liquid container of this device

Technical field

The present invention relates to a kind of liquid-detecting and be furnished with the liquid container of this device, particularly be suitable for the liquid-detecting that the liquid residue in the liquid injection apparatus is detected and be furnished with the liquid container of this device.

Background technology

The typical example of liquid injection apparatus in the past has the inkjet recording device that has been equipped with the ink jet recording head that image recording uses.Other liquid injection apparatus for example can exemplify out: the device of being furnished with employed colored materials shower nozzle in the color filter of LCD etc. is made; The device of being furnished with employed electrode material in the electrode of OLED display, face active display (FED) etc. forms (conduction is stuck with paste) shower nozzle; The device of being furnished with employed live body organism shower nozzle in biochip is made; Is furnished with device as the sample shower nozzle of accurate bulb etc.

In inkjet recording device as the typical example of liquid injection apparatus, ink jet recording head is loaded on the carriage, and wherein said ink jet recording head has pressure generation unit that pressure generating chamber is pressurizeed and the nozzle opening that pressurized ink is sprayed as ink droplet.

In inkjet recording device, the ink in the ink tank is continued to be fed to record-header via stream, thereby make printing to be continued.Ink tank for example is constituted as removably box body, can be changed simply by the user in the moment that ink is consumed.

In the past, the management method of the consumption of ink of print cartridge had by software to the ejection number of the ink droplet on the record-header with owing to safeguard the quantity of ink that is sucked out and add up, thus the method for managing consumption of ink by calculating; And by the electrode be used to detect liquid level is installed on print cartridge, thereby to the ink actual consumption method that manages of moment of scheduled volume etc.

But, thereby adding up to manage in the method for consumption of ink by the ejection number or the quantity of ink of software by calculating to ink droplet, there are the following problems.In the middle of shower nozzle, has deviation of weight on the ejection ink droplet.Though the deviation of weight of this ink droplet can not bring influence to picture quality,, the error of considering the caused exhausted amount of ink of this deviation has been filled the ink of the amount with surplus by the situation of accumulative total in print cartridge.Therefore, can produce the problem of ink of being left the amount of surplus according to the difference of individuality.

On the other hand, the method that the moment that is consumed by the electrode pair ink manages is owing to detecting the actual amount of ink, so can manage the ink surplus with high reliability.But,, limited the kind of detectable ink, the complicated shortcoming of seal construction of electrode so exist because the detection of ink level depends on the electric conductivity of ink.In addition, be the noble metal that electric conductivity is good and corrosion resistance is high owing to the material of electrode is normally used, thereby improved the manufacturing cost of print cartridge.In addition, owing to need two electrodes are installed,, consequently increased manufacturing cost so manufacturing process increases.

Open in the 2001-146024 communique the Japanese documentation spy and be disclosed for addressing the above problem the device that develops as piezo-electric device.This piezo-electric device can correctly detect liquid residue, and does not need complicated seal construction, and can be installed on the liquid container and use.

Promptly, open the described piezo-electric device of 2001-146024 communique according to the Japanese documentation spy, when in the space relative ink being arranged and when not having ink (perhaps seldom) with the vibration section of piezo-electric device, because the resonant frequency of the residual vibration signal that the residual vibration (free vibration) of the vibration section by the piezo-electric device after the driving pulse forced vibration produces changes, utilize this situation can monitor the ink surplus that print cartridge is interior.

Figure 24 A, Figure 24 B and Figure 24 C show the actuator that constitutes above-mentioned piezo-electric device in the past.This actuator 106 has: substrate 178 has circular open 161 in substantial middle; Oscillating plate 176 is configured on the face (hereinafter referred to as " surface ") of substrate 178, so that cover opening 161; Piezoelectric layer 160 is configured in surface one side of oscillating plate 176; Upper electrode 164 and lower electrode 166 clip piezoelectric layer 160 from both direction; Upper electrode terminal 168 is with upper electrode 164 electrical bond; Lower electrode terminal 170 is with lower electrode 166 electrical bond; And auxiliary electrode 172, be configured between upper electrode 164 and the upper electrode terminal 168 and with the two electrical bond.

Piezoelectric layer 160, upper electrode 164 and lower electrode 166 have the conduct circular portion of main part separately.And piezoelectric layer 160, upper electrode 164 and lower electrode 166 circular portion separately forms piezoelectric element.

Oscillating plate 176 is formed on the surface of substrate 178, and covers opening 161.Chamber 162 is by forming towards the part of opening 161 and the opening 161 of substrate (chamber forms parts) 178 in the oscillating plate 176.The face of an opposite side with piezoelectric element in the substrate 178 (hereinafter referred to as " back side ") is towards the ink tank inboard.Thus, chamber 162 is constituted as with liquid (ink) and contacts.In addition, with oscillating plate 176 liquid-seal types be installed on the substrate 178, do not have surface one side that liquid drains to substrate 178 in the chamber 162 even make liquid enter into yet.

Lower electrode 166 is positioned on the surface of oscillating plate 176.Center as the circular portion of lower electrode 166 main parts is installed into consistent with the center of opening 161.In addition, at configuration of the surface of lower electrode 166 side and formation piezoelectric layer 160, and make the center of its circular portion consistent with the center of opening 161.

Then, in the actuator in described conventional art (piezo-electric device) 106, the size (area) that the size of the circular portion of lower electrode 166 (area) is set to ratio open 161 is little, thereby the circular portion of lower electrode 166 is configured in the scope in its integral body and opening 161 corresponding zones.In addition, the area that the area of the circular portion of piezoelectric layer 160 is set to ratio open 161 is little, and bigger than the area of the circular portion of lower electrode 166.

In the surface of piezoelectric layer 160 side configuration and form upper electrode 164, and make as the center of the circular portion of its main part consistent with the center of opening 161.The area of circular portion that the area of the circular portion of upper electrode 164 is set to ratio open 161 and piezoelectric layer 160 is little, and bigger than the area of the circular portion of lower electrode 166.

Therefore, the structure that is clipped in the middle from a surperficial side and the back side one side respectively by the main part of the main part of upper electrode 164 and lower electrode 166 of the main part of piezoelectric layer 160.Separately main part of piezoelectric layer 160, upper electrode 164 and lower electrode 166, be that circular portion has formed the piezoelectric element in the actuator 106.This piezoelectric element links to each other with oscillating plate 176.

Owing to be this structure, the vibration area of actual vibration is determined by opening 161 in the oscillating plate 176.In addition, in the circular portion of the circular portion of the lower electrode 166 that is electrically connected with piezoelectric layer 160 and upper electrode 164, because the circular portion of lower electrode 166 is less, so the circular portion of lower electrode 166 has determined to produce in the piezoelectric layer 160 part of piezoelectric effect.

As mentioned above, in the actuator 106 (piezo-electric device) in the prior art, in the circular body part and circular open 161 of the circular body part of the circular body of upper electrode 164 part, piezoelectric layer 160, lower electrode 166, the area maximum be opening 161, secondly big is the main part of piezoelectric layer 160, secondly be the main part of upper electrode 164 again, minimum is the main part of lower electrode 166.

In addition, in the actuator 106 in above-mentioned conventional art, apply driving pulse and the residual vibration (free vibration) of the oscillating component that is produced after the oscillating component forced vibration is detected as back electromotive force by identical piezoelectric element to piezoelectric element.Then, the liquid level in ink tank is provided with before and after the position (being the position in chamber 162 strictly speaking) by actuator 106, and the residual vibration state of oscillating component can change, and utilizes this phenomenon can detect ink surplus in the ink tank.

Yet, in above-mentioned liquid-detecting (piezo-electric device) in the past, have following problems.

The first, the residual vibration of the oscillating component by liquid-detecting and the output of the back electromotive force that produces in piezoelectric element is very little, thereby make the detection difficult of back electromotive force.This is considered to, owing to applying driving pulse to piezoelectric element so that deformed shape (deformation pattern) difference of the oscillating component during the automatic vibration behind the deformed shape (deformation pattern) of the oscillating component during its forced vibration and the imposed deformation is very big causes.

The second, in the middle of the free vibration of the oscillating component behind the imposed deformation, except vibration frequency, also excited the vibration mode of unnecessary high order as necessity of detected object.Particularly, if produced deviation owing to manufacture deviation makes the position of the lower electrode in the oscillating component, then unnecessary vibration increases, and difference according to circumstances has the situation that can't detect or can't correctly detect.

In addition, by Figure 24 A, Figure 24 B and Figure 24 C as can be known, in liquid-detecting (piezo-electric device) in the past, the part of hard and fragile piezoelectric film 160 is extended to top electrode terminal 168 1 sides, and the edge in crosscut chamber 162.Therefore, with corresponding position, the edge in chamber 162 on, on piezoelectric film 160, can crack.

Summary of the invention

The present invention considers that just above-mentioned situation finishes, its purpose be to provide a kind of can be easily and detect the liquid-detecting of residual vibration state of oscillating component and the liquid container of being furnished with this device reliably.

In addition, the present invention also aims to provide a kind of and can prevent liquid-detecting that cracks in the piezoelectric layer and the liquid container of being furnished with this device.

In order to address the above problem, liquid-detecting of the present invention comprises: base portion, it has first and second respect to one another, be used to admit the recess as the medium of detected object to be formed in described first one side opening, and the bottom surface of described recess is formed and can vibrates; First electrode, it is formed at described second one side of described base portion, and has a main part, wherein said main part forms with the size bigger than the bottom surface of described recess, thereby cover the almost whole zone corresponding with the bottom surface of described recess, and described main part comprises recessed to the inside from the position corresponding with the edge of the bottom surface of described recess and notch that form; Piezoelectric layer, it has the main part that forms with than the little size in the bottom surface of described recess, and all be received in the scope in the zone corresponding with the bottom surface of described recess, wherein, the described main part of described piezoelectric layer is except the part corresponding with the described notch of described first electrode, and it roughly all is layered on described first electrode; Auxiliary electrode, it is formed at described second one side of described base portion, and extend to inside with corresponding zone, the bottom surface of described recess from the outside in the zone corresponding with the bottom surface of described recess, and its part is positioned at the inside of the described notch of described first electrode, and supports a part of described piezoelectric layer from described second one side; With second electrode, it has main part and extension, wherein said main part is layered on the described piezoelectric layer, and described extension extends out from described main part, and is connected with described auxiliary electrode in the inside in the zone corresponding with the bottom surface of described recess.

In addition, preferably, described piezoelectric layer has outshot, and described outshot described main part from described piezoelectric layer in the scope in the zone corresponding with the bottom surface of described recess is outstanding, and described outshot is supported by described auxiliary electrode.

In addition, preferably, the described main part of described second electrode forms with the size littler than the described main part of described piezoelectric layer.

In addition, preferably, the described main part of described piezoelectric layer and the described main part of described second electrode are the roughly shape of symmetry with at least one shared axis of symmetry.

In addition, preferably, the described main part of described piezoelectric layer and the described main part of described second electrode all are circular, and are disposed with one heart mutually.

In order to address the above problem, liquid-detecting of the present invention comprises: comprising: base portion, it has first and second respect to one another, be used to admit the recess as the medium of detected object to be formed in described first one side opening, and the bottom surface of described recess is formed and can vibrates; First electrode, it is formed on described second one side of described base portion with the size bigger than the bottom surface of described recess, thereby covers the whole zone corresponding with the bottom surface of described recess; Piezoelectric layer, it has main part, described main part forms with the size littler than the bottom surface of described recess, and in the inner laminated in the zone corresponding with the bottom surface of described recess on described first electrode; With second electrode, it has the main part on the described main part that is layered in described piezoelectric layer.

In addition, preferably, described piezoelectric layer also has the extension, and described extension extends out from the described main part of described piezoelectric layer, and crosses the position corresponding with the edge of described recess and extend to outside with corresponding zone, the bottom surface of described recess.

In addition, preferably, described second electrode also has the extension, and described extension extends out from the described main part of described second electrode, the top, described extension of the described piezoelectric layer of extend past, and extend to the outside in the zone corresponding with the bottom surface of described recess.

In addition, preferably, the described main part of described recess, described piezoelectric layer and the described main part of described second electrode all are circular, and are disposed with one heart mutually.

In addition, preferably, also have between the described extension of described second electrode and the insulation course between the described piezoelectric layer.

In order to address the above problem, liquid-detecting of the present invention comprises: base portion, it has first and second respect to one another, be used to admit the recess as the medium of detected object to be formed in described first one side opening, and the bottom surface of described recess is formed and can vibrates; First electrode, it is formed on described second one side of described base portion with the size bigger than the bottom surface of described recess, thereby covers the whole zone corresponding with the bottom surface of described recess; Piezoelectric layer, it has main part, and described main part forms with the size bigger than the bottom surface of described recess, and covers the whole zone corresponding with the bottom surface of described recess and be layered on described first electrode; With second electrode, it has main part, and described main part forms with the size littler than the bottom surface of described recess, and on the described main part of inner laminated at described piezoelectric layer in the zone corresponding with the bottom surface of described recess.

In addition, preferably, the described main part of described piezoelectric layer forms with the size littler than the described main part of described first electrode.

In addition, preferably, described piezoelectric layer also has the extension that extends out from the described main part of described piezoelectric layer; Described second electrode also has the extension, and described extension extends out from the described main part of described second electrode, and the described main part of the described piezoelectric layer of extend past and top, described extension.

In addition, preferably, the described main part of described recess and described second electrode all is circular, and is disposed with one heart mutually.

In order to address the above problem, liquid-detecting of the present invention comprises: base portion, it has first and second respect to one another, be used to admit the recess as the medium of detected object to be formed in described first one side opening, and the bottom surface of described recess is formed and can vibrates; First electrode, it has main part, and described main part is formed on described second one side of described base portion with the size littler than the bottom surface of described recess, and is configured in the inside in the zone corresponding with the bottom surface of described recess; Piezoelectric layer, it has main part, and this main part forms with the size littler than the described main part of described first electrode, and is layered on the described main part of described first electrode; With second electrode, it has main part, and described main part forms with the size littler than the described main part of described piezoelectric layer, and is layered on the described main part of described piezoelectric layer.

In addition, preferably, described first electrode also has the extension, and described extension extends out from the described main part of described first electrode, and extends to the outside in the zone corresponding with the bottom surface of described recess; Described piezoelectric layer also has the extension, and described extension extends out from the described main part of described piezoelectric layer, and extends to the outside in the zone corresponding with the bottom surface of described recess; Described second electrode also has the extension, and described extension extends out from the described main part of described second electrode, and the described main part of the described piezoelectric layer of extend past and top, described extension.

In addition, preferably, the described main part of described recess and described first electrode all is circular, and is disposed with one heart mutually; The size of the diameter of the described main part of described first electrode is more than 75% of diameter of described recess.

In order to address the above problem, liquid-detecting of the present invention comprises: base portion, it has first and second respect to one another, be used to admit the recess as the medium of detected object to be formed in described first one side opening, and the bottom surface of described recess is formed and can vibrates; First electrode, it is formed on described second one side of described base portion with the size bigger than the bottom surface of described recess, thereby covers the whole zone corresponding with the bottom surface of described recess; Piezoelectric layer, it has main part, and described main part forms with the size bigger than the bottom surface of described recess, and covers the whole zone corresponding with the bottom surface of described recess and be layered on described first electrode; With second electrode, it has the main part of annular, and described main part forms with the race diameter size littler than the bottom surface of described recess, and on the described main part of inner laminated at described piezoelectric layer in the zone corresponding with the bottom surface of described recess.

In addition, preferably, described recess is circular; The described main part of described second electrode is an annular; The described main part of described recess and described second electrode is disposed mutually with one heart.

In order to address the above problem, liquid-detecting of the present invention comprises: base portion, it has first and second respect to one another, be used to admit the recess as the medium of detected object to be formed in described first one side opening, and the bottom surface of described recess is formed and can vibrates; First electrode, it is formed at described second one side of described base portion, and have main part and an extension, wherein said main part forms with the size littler than the bottom surface of described recess, and be configured in the inside in the zone corresponding with the bottom surface of described recess, described extension extends out from described main part, and extends to the outside in the zone corresponding with the bottom surface of described recess; Piezoelectric layer, it forms with the size littler than the bottom surface of described recess, and is layered on described first electrode, and it all is configured in the inside in the zone corresponding with the bottom surface of described recess; Auxiliary electrode, it is formed at described second one side of described base portion, and extend to inside with corresponding zone, the bottom surface of described recess from the outside in the zone corresponding with the bottom surface of described recess, and its part supports a part of described piezoelectric layer from described second one side; With second electrode, it has main part and extension, wherein said main part is layered on the described piezoelectric layer, and described extension extends out and is connected with described auxiliary electrode in the inside in the zone corresponding with the bottom surface of described recess from described main part.

In addition, preferably, the size of the described main part of described first electrode is littler than the size of described piezoelectric layer; The size of the described main part of described second electrode is bigger than the size of the described main part of described first electrode.

In addition, preferably, the size of the described main part of described second electrode is littler than the size of described piezoelectric layer.

In addition, preferably, the described extension of described first electrode and the described extension of described second electrode opposite towards each other direction on first straight line at the center by described recess is extended; Described first electrode also has a pair of extension, described a pair of extension the center by described recess and with vertical second straight line of described first straight line on extend from the opposite towards each other direction of the described main part of described first electrode.

In addition, preferably, separate with the described main part of described first electrode described a pair of extension.

In addition, preferably, the described main part of the described main part of described first electrode, described piezoelectric layer and the described main part of described second electrode all are circular, and are disposed with one heart mutually.

In order to address the above problem, liquid container of the present invention is characterised in that, comprise the container body and the described arbitrary liquid-detecting that are used for storaging liquid, wherein, the described recess of described liquid-detecting is exposed in the fluid storage space of described container body.

In addition, preferably, store the liquid that liquid injection apparatus is used in the described container body.

In addition, preferably, described liquid injection apparatus is an inkjet recording device; Store ink in the described container body.

According to liquid-detecting among the present invention who forms by said structure and the liquid container of being furnished with this device, can be easily and detect the variation of residual vibration state of the oscillating component of liquid-detecting reliably.

In addition, the liquid-detecting in according to the present invention and be furnished with the liquid container of this device can prevent the generation of the crackle in the piezoelectric layer reliably.

Description of drawings

Fig. 1 is the stereographic map of the brief configuration of expression inkjet recording device, and this inkjet recording device has used the print cartridge of the liquid-detecting with an embodiment of the present invention;

Fig. 2 is the planimetric map of the liquid-detecting of expression an embodiment of the present invention;

Fig. 3 A and Fig. 3 B are the longitudinal sections that amplifies a part that shows liquid-detecting shown in Figure 2, and Fig. 3 A shows along the cross section of the A-A line of Fig. 2, and Fig. 3 B shows along the cross section of the B-B line of Fig. 2;

Fig. 4 is the periphery of the liquid-detecting shown in Fig. 2, Fig. 3 A and Fig. 3 B and the synoptic diagram of equivalent circuit thereof;

Fig. 5 A shows by the resonant frequency of the detected oscillating component of liquid-detecting shown in Fig. 2, Fig. 3 A and Fig. 3 B and the relation between the ink surplus in the print cartridge;

Fig. 5 B shows the resonant frequency of the detected ink of liquid-detecting shown in Fig. 2, Fig. 3 A and Fig. 3 B and the relation between the ink density;

Fig. 6 A and Fig. 6 B are the synoptic diagram of the back emf waveform in the liquid-detecting shown in Fig. 2, Fig. 3 A and Fig. 3 B;

Fig. 7 is packed into the skeleton view of module body of the liquid-detecting shown in Fig. 2, Fig. 3 A and Fig. 3 B of expression;

Fig. 8 is the exploded view of the structure of expression module body shown in Figure 7;

Fig. 9 is the synoptic diagram that module body shown in Figure 7 is installed to the example in the cross section on the container body of print cartridge;

Figure 10 is the planimetric map of the liquid-detecting of expression an embodiment of the present invention;

Figure 11 A and Figure 11 B are the longitudinal sections that amplifies the part that liquid-detecting shown in Figure 10 is shown, and Figure 11 A shows along the cross section of the A-A line of Figure 10, and Figure 11 B shows along the cross section of the B-B line of Figure 10;

Figure 12 is the sectional view of a variation of the liquid-detecting shown in Figure 10, Figure 11 A and Figure 11 B;

Figure 13 is the planimetric map of the liquid-detecting of expression an embodiment of the present invention;

Figure 14 A and Figure 14 B are the longitudinal sections that amplifies the part that liquid-detecting shown in Figure 13 is shown, and Figure 14 A shows along the cross section of the A-A line of Figure 13, and Figure 14 B shows along the cross section of the B-B line of Figure 13;

Figure 15 is the sectional view of a variation of the liquid-detecting shown in Figure 13, Figure 14 A and Figure 14 B;

Figure 16 is the planimetric map of the liquid-detecting of expression an embodiment of the present invention;

Figure 17 A and Figure 17 B are the longitudinal sections that amplifies the part that liquid-detecting shown in Figure 16 is shown, and Figure 17 A shows along the cross section of the A-A line of Figure 16, and Figure 17 B shows along the cross section of the B-B line of Figure 16;

Figure 18 is the planimetric map of the liquid-detecting of expression an embodiment of the present invention;

Figure 19 A and Figure 19 B are the longitudinal sections that amplifies the part that liquid-detecting shown in Figure 180 is shown, and Figure 19 A shows along the cross section of the A-A line of Figure 18, and Figure 19 B shows along the cross section of the B-B line of Figure 18;

Figure 20 is the planimetric map of the liquid-detecting of expression an embodiment of the present invention;

Figure 21 A and Figure 21 B are the longitudinal sections that amplifies the part that liquid-detecting shown in Figure 20 is shown, and Figure 21 A shows along the cross section of the A-A line of Figure 20, and Figure 21 B shows the cross section of the B-B line of Figure 20;

Figure 22 is the planimetric map of expression as the liquid-detecting of a variation of the embodiment shown in Figure 20, Figure 21 A and Figure 21 B;

Figure 23 A and Figure 23 B are the longitudinal sections that amplifies the part that liquid-detecting shown in Figure 22 is shown, and Figure 23 A shows along the cross section of the A-A line of Figure 22, and Figure 23 B shows along the cross section of the B-B line among Figure 22;

Figure 24 A, Figure 24 B and Figure 24 C are the synoptic diagram of liquid-detecting in the past.

Embodiment

Below, with reference to accompanying drawing the liquid-detecting of an embodiment of the present invention and the print cartridge (liquid container) of being furnished with this liquid-detecting are described.

Fig. 1 shows the brief configuration of the inkjet recording device (liquid injection apparatus) of the print cartridge that uses present embodiment, label 1 is a carriage among Fig. 1, this carriage 1 is with 3 to be directed to parts 4 and lead by what driven by carriage motor 2 synchronously, thereby moves back and forth on cylinder 5 axial.

Side relative with paper used for recording 6 at carriage 1 is mounted with ink jet recording head 12, and at an upper portion thereof print cartridge 7 is installed releasably, and this print cartridge 7 is used for to record-header 12 supply inks.

At the non-printing zone of this pen recorder, be that reference position (right side among the figure) disposes cap assembly 31, when the record-header on being loaded into carriage 1 moves to reference position, this cap assembly 31 hides on the nozzle formation face of record-header, thereby forms seal cavity between itself and nozzle formation face.In addition, below cap assembly 31, dispose pump unit 10, be used for applying negative pressure to implement cleaning etc. to the seal cavity that forms by cap assembly 31.

In addition, in cap assembly 31 printing zone one side near, disposed the wiping arrangement 11 that has elastic plates such as rubber, and this wiping arrangement 11 can for example be advanced and retreat in the horizontal direction with respect to the motion track of record-header, thereby when carriage 1 when cap assembly 31 1 sides move back and forth, the nozzle of wiping record-header forms face as required.

Fig. 2, Fig. 3 A and Fig. 3 B are the synoptic diagram of the liquid-detecting 60 of present embodiment, and this liquid-detecting 60 has stacked oscillating plate 42 on substrate 41 and the base portion 40 of formation, and this base portion 40 has first 40a respect to one another and second 40b.Be formed with circular chamber (recess) 43 in base portion 40, be used to admit the medium as detected object, and this chamber 43 is at first 40a one side opening, the bottom surface sections 43a in chamber 43 is formed can be by oscillating plate 42 vibrations.In other words, the part of actual vibration has been stipulated its profile by chamber 43 in the whole oscillating plate 42.Two ends in second 40b one side of base portion 40 are formed with lower electrode terminal 44 and upper electrode terminal 45.

On second 40b of base portion 40, be formed with lower electrode (first electrode) 46, this lower electrode 46 has the main part 46a and the extension 46b of sub-circular, and wherein said extension 46b is connected to the direction extension of bottom electrode terminal 44 and with lower electrode terminal 44 from described main part 46a.The center of the main part 46a of the sub-circular of lower electrode 46 is consistent with the center in chamber 43.

The diameter of the main part 46a of the sub-circular of lower electrode 46 is formed greatlyyer than circular chamber 43, and covers the corresponding zone in nearly all and chamber 43.In addition, the main part 46a of the sub-circular of this lower electrode 46 comprises from the chamber notch 46c that 43 the pairing position of edge 43a is recessed to the inside and form.

Stacked piezoelectric layer 47 on lower electrode 46, this piezoelectric layer 47 have the diameter circle littler than chamber 43 main part 47a and with the scope in 43 corresponding zones, chamber in from the outstanding outshot 47b of main part 47a.As can be seen from Figure 2, whole piezoelectric layer 47 all is incorporated in the scope with 43 corresponding zones, chamber.In other words, piezoelectric layer 47 does not have the part of the corresponding position of 43a, edge in crosscut and extend past and chamber 43 fully.

The center of the main part 47a of piezoelectric layer 47 is consistent with the center in chamber 43, and the main part 47a of piezoelectric layer 47 except with the corresponding part of notch 46c of lower electrode 46, it roughly all is laminated on the lower electrode 46.

Second 40b one side at base portion 40 is formed with auxiliary electrode 48.The outside of this auxiliary electrode 48 43 The corresponding area from the chamber is crossed the pairing position of edge 43a in chamber 43 and is extended to the inside of chamber 43 The corresponding area.The part of auxiliary electrode 48 is positioned at the inside of the notch 46c of first electrode 46, and from second 40b one side of substrate 40 to the extension 47b of piezoelectric layer 47 and near support.This auxiliary electrode 48 preferably has material identical with lower electrode 46 and identical thickness.Like this, by auxiliary electrode 48 from second 40b one side of substrate 40 to the extension 47b of piezoelectric layer 47 and near support, it is poor can not to produce ladder on piezoelectric layer 47, thereby can prevent the reduction of physical strength.

The main part 49a of the circle of stacked upper electrode (second electrode) 49 on piezoelectric layer 47, this upper electrode 49 is formed the main part 47a of diameter less than piezoelectric layer 47.In addition, upper electrode 49 has the extension 49b that extends out and be connected with auxiliary electrode 48 from main part 49a.By Fig. 3 B as can be known, the extension 49b of upper electrode 49 and the position P that being connected of auxiliary electrode 48 begins are positioned at the scope of chamber 43 The corresponding area.

As shown in Figure 2, upper electrode 49 is electrically connected with upper electrode terminal 45 by auxiliary electrode 48.Via auxiliary electrode 48 upper electrode 49 is connected on the upper electrode terminal 45 like this, it is poor to absorb the ladder that produces from the gross thickness of piezoelectric layer 47 and lower electrode 46 by upper electrode 49 and auxiliary electrode 48 both sides.Therefore, thus can prevent from upper electrode 49 to produce the situation that big ladder difference causes physical strength to reduce.

The main part 49a of upper electrode 49 forms circle, and its center is consistent with the center in chamber 43.It is all littler than the diameter in the main part 47a of piezoelectric layer 47 and chamber 43 that the main part 49a of upper electrode 49 is formed diameter.

So, the main part 47a of piezoelectric layer 47 becomes the structure that is clipped in the middle by the main part 46a of the main part 49a of upper electrode 49 and lower electrode 46.Thus, can be out of shape driving piezoelectric layer 47 effectively.

In addition, in the main part 49a of the main part 46a of the lower electrode 46 that is electrically connected with piezoelectric layer 47 and upper electrode 49, the diameter of the main part 49a of upper electrode 49 is less.Therefore, the main part 49a of upper electrode 49 has determined to produce the scope of the part of piezoelectric effect in piezoelectric layer 47.

In addition, the parts that are contained in the liquid-detecting 60 preferably form as one mutually by sintering.By forming liquid-detecting 60 like this, can make the utilization of liquid-detecting 60 become easy.

The material of piezoelectric layer 47 preferably uses lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT) or does not use plumbous leadless piezoelectric film.The material of substrate 41 preferably uses zirconia or aluminium oxide.In addition, oscillating plate 42 preferably uses and substrate 41 identical materials.Upper electrode 49, lower electrode 46, upper electrode terminal 45 and lower electrode terminal 44 can use the material with electric conductivity, for example use metals such as gold, silver, copper, platinum, aluminium, nickel.

About the main part 47a of piezoelectric layer 47, the main part 49a of upper electrode 49 and the main part 46a of lower electrode 46, their center is consistent with the center in chamber 43.In addition, but determine oscillating plate 42 oscillating component circle chamber 43 be centered close to whole liquid pick-up unit 60 in the heart.

But constituted the oscillating component 61 of liquid-detecting 60 with the corresponding part in chamber 43 by the main part 49a of the main part 47a of part corresponding among the main part 46a of the oscillating component of the oscillating plate 42 of chamber 43 regulation, lower electrode 46, piezoelectric layer 47 and outshot 47b and upper electrode 49 and extension 49b with chamber 43.In addition, the center of the oscillating component 61 of this liquid-detecting 60 is consistent with the center of liquid-detecting 60.

In addition, but the oscillating component of the main part 46a of the main part 49a of the main part 47a of piezoelectric layer 47, upper electrode 49, lower electrode 46 and oscillating plate 42 (promptly corresponding with the bottom surface portions 43a in chamber 43 part) has circular shape, and, whole piezoelectric layer 47, be the inside that the main part 47a of piezoelectric layer 47 and extension 47b are configured in the zone corresponding with chamber 43, thereby the oscillating component 61 of liquid-detecting 60 is with respect to the center of liquid-detecting 60 shape of symmetry substantially.

So, in the present embodiment, owing to cover the corresponding zone in almost whole and chamber 43 with the main part 46a of lower electrode 46, thus compared with the past, the difference between the deformation pattern when deformation pattern when having reduced forced vibration and free vibration.In addition, because the oscillating component 61 of liquid-detecting 60 is the centrosymmetric shapes with respect to liquid-detecting 60, so from this center, the rigidity of described oscillating component 61 is isotropy substantially.

Therefore, suppressed generation owing to the unnecessary vibration that produces of asymmetry of structure, and when having prevented owing to forced vibration and the output reduction of the back electromotive force that causes of the difference of the deformation pattern between during free vibration.Thus, the accuracy of detection of the resonant frequency of the residual vibration in the oscillating component 61 of liquid-detecting 60 is improved, and the detection of the residual vibration of oscillating component 61 also becomes easy.

In addition, because the main part 46a with the diameter lower electrode 46 bigger than chamber 43 covers the almost zone of whole cavity 43 correspondences, so the unnecessary generation of vibration that the position deviation of lower electrode 46 causes in the time of can preventing owing to manufacturing can prevent the reduction of accuracy of detection.

In addition, hard and fragile whole piezoelectric layer 47 is configured in the inside in the zone corresponding with chamber 43, thereby on the position corresponding, does not have piezoelectric layer 47 with the edge 43a in chamber 43.Therefore, the problem of the crackle of the piezoelectric film that in liquid-detecting in the past, on the position corresponding, does not produce with the edge in chamber.

In addition, because the scope that oscillating component 61 contacts with liquid is only limited to chamber 43 existing scopes,, thus, can detect the ink level in the print cartridge 7 accurately so can accurately carry out the detection of liquid.

Fig. 4 shows employed in the present embodiment liquid-detecting 60 and equivalent circuit thereof.This liquid-detecting 60 detects the variation of acoustic impedance by the resonant frequency that detects residual vibration, thereby detects the consumption state of the liquid in the print cartridge.

(A) of Fig. 4 and (B) of Fig. 4 show the equivalent circuit of liquid-detecting 60.In addition, (C) of Fig. 4 and (D) of Fig. 4 show periphery and the equivalent circuit thereof that comprises liquid-detecting 60 when being full of ink in print cartridge 7 respectively, and (E) of Fig. 4 and (F) of Fig. 4 show respectively when the periphery and the equivalent circuit thereof that comprise liquid-detecting 60 in the print cartridge 7 during no ink.

Fig. 2 is installed in the predetermined place of the container body of print cartridge 7 to liquid-detecting 60 shown in Figure 4, and makes the interior stored liquid (ink) of chamber 43 and container body contact.That is, at least a portion of the oscillating component 61 of liquid-detecting 60 is exposed in the storage area of container body.When fully having stored liquid in container body, in the chamber 43 and outside is filled up by liquid.

On the other hand, liquid (ink) when the container body inside of print cartridge 7 is consumed, and when liquid level drops to the below of installation site (being the position in chamber 43 strictly speaking) of liquid-detecting 60, just become the state that does not have liquid in the chamber 43, or residual liquid and have the state of gas in its outside in chamber 43 only.

The difference of the caused acoustic impedance of variation of 60 pairs of these states of liquid-detecting detects.Thus, it is the state that is fully storing liquid in the container body that liquid-detecting 60 can detect, and has still consumed the state of certain a certain amount of above liquid.

Then, the principle to the level detection in the liquid-detecting 60 of present embodiment describes.

Liquid-detecting 60 can utilize the variation of resonant frequency to come the variation of the acoustic impedance of tracer liquid.Resonant frequency can detect by measuring back electromotive force, and wherein said back electromotive force is that the residual vibration that oscillating component 61 vibrations by liquid-detecting 60 remain on the oscillating component 61 is later produced.Promptly, if apply after thereby driving pulse makes oscillating component 61 forced vibrations at piezoelectric layer 47 to liquid-detecting 60, make oscillating component 61 free vibrations, then owing to the residual vibration (free vibration) in the oscillating component 61 of liquid-detecting 60, piezoelectric layer 47 produces back electromotive force.The size of this back electromotive force changes according to the amplitude of the oscillating component 61 of liquid-detecting 60.Therefore, the amplitude of the residual vibration (free vibration) of the oscillating component 61 of liquid-detecting 60 is big more, and the detection of the output of back electromotive force is just easy more.

In addition, cycle of changing of the size of back electromotive force changes according to the frequency of the residual vibration in the oscillating component 61 of liquid-detecting 60.That is, the frequency of the oscillating component 61 of liquid-detecting 60 is corresponding with the frequency of back electromotive force.Here, resonant frequency is meant the oscillating component 61 and the frequency of medium under resonance state that is connected with this oscillating component 61 of liquid-detecting 60.

When in the container body of print cartridge 7, fully having stored liquid (ink), in the chamber 43 of liquid-detecting 60, be full of liquid, the interior liquid phase of the oscillating component 61 bottom surface portions 43a by chamber 43 and container body contacts.On the other hand, when liquid was insufficient in the container body, liquid phases residual in the oscillating component 61 of liquid-detecting 60 and the chamber 43 contacted, and did not perhaps contact with liquid and contacted with gas or vacuum.

Here, with reference to Fig. 2 to Fig. 4, the action and the principle of the liquid condition in the container body that detects print cartridge 7 is described from the resonant frequency of the oscillating component 61 of the medium that obtains by the measurement of back electromotive force and liquid-detecting 60.

In liquid-detecting 60,, apply voltage to upper electrode 49 and lower electrode 46 respectively by upper electrode terminal 45 and lower electrode terminal 44.So, produce electric field on the part that in piezoelectric layer 47, is clipped in the middle by upper electrode 49 and lower electrode 46.By this electric field, piezoelectric layer 47 deforms.Because piezoelectric layer 47 deforms, make that bending vibration takes place the vibration area (zone corresponding with the bottom surface portions 43a in chamber 43) in the oscillating plate 42.After forcing to make piezoelectric layer 47 distortion, in a period of time, bending vibration can remain in the oscillating component 61 of liquid-detecting 60.

This residual vibration is the free vibration of oscillating component 61 with the medium of liquid-detecting 60.Therefore, be pulse waveform or square wave by making the voltage that is applied on the piezoelectric layer 47, can easily obtain to apply the resonance state of oscillating component 61 and medium behind the voltage.Residual vibration is the vibration of the oscillating component 61 of liquid-detecting 60, and with the distortion of piezoelectric layer 47.Therefore, piezoelectric layer 47 produces back electromotive force along with residual vibration.This back electromotive force can detect via upper electrode 49, lower electrode 46, upper electrode terminal 45 and lower electrode terminal 44.Owing to can determine resonant frequency, no liquid (ink) is arranged so can detect in the container body of print cartridge 7 based on this resonant frequency by this detected back electromotive force.

Usually, resonant frequency fs can represent with following formula:

Fs=1/ (2* π * (M*Cact) ^1/2) (formula 1).

Here, M is inertia (inertance) Mact and the additional inertial M ' sum of oscillating component 61.Cact is the flexibility of oscillating component 61.

(A) of Fig. 4 and (B) of Fig. 4 are the not oscillating component 61 of the liquid-detecting 60 during residual ink and the equivalent circuits in chamber 43 in the chamber 43.

The long-pending area divided by oscillating component 61 of the density of the thickness of Mact oscillating component 61 and oscillating component 61 obtains, and in detail, it can be represented by the formula shown in Fig. 4 (A):

Mact=Mpzt+Melectrode1+Melectrode2+Mvib (formula 2).

Here, the long-pending area divided by piezoelectric layer 47 of the density of the thickness of the piezoelectric layer 47 in the Mpzt oscillating component 61 and piezoelectric layer 47 obtains.The long-pending area divided by upper electrode 49 of the thickness of the upper electrode 49 in the Melectrode1 oscillating component 61 and the density of upper electrode 49 obtains.The long-pending area divided by lower electrode 46 of the thickness of the lower electrode 46 in the Melectrode2 oscillating component 61 and the density of lower electrode 46 obtains.The area of the long-pending vibration area divided by oscillating plate 42 of the thickness of the oscillating plate 42 in the Mvib oscillating component 61 and the density of oscillating plate 42 obtains.

Wherein, in order to calculate Mact from thickness, density and the area of the integral body of oscillating component 61, preferably, the vibration area area separately of piezoelectric layer 47, upper electrode 49, lower electrode 46 and oscillating plate 42 has magnitude relationship as described above, but the difference of area each other is very small.

In addition, in the present embodiment,, preferably little of negligible degree with respect to main part as main part 47a, the 49a of the circle of their major parts, part beyond the 46a about piezoelectric layer 47, upper electrode 49 and lower electrode 46.Therefore, in liquid-detecting 60, Mact is the vibration area inertia sum separately in upper electrode 49, lower electrode 46, piezoelectric layer 47 and the oscillating plate 42.In addition, flexibility Cact is the flexibility of the part that formed by the vibration area in upper electrode 49, lower electrode 46, piezoelectric layer 47 and the oscillating plate 42.

In addition, (A) of Fig. 4, (B), (D), (F) show the oscillating component 61 of liquid-detecting 60 and the equivalent circuit in chamber 43, in these equivalent circuits, and the flexibility of the oscillating component 61 of Cact express liquid pick-up unit 60.Cpzt, Celectrode1, Celectrode2 and Cvib represent the flexibility of piezoelectric layer 47, upper electrode 49, lower electrode 46 and oscillating plate 42 in the oscillating component 61 respectively.Cact can represent with following formula 3:

1/Cact＝(1/Cpzt)+(1/Celectrode1)+(1/Celectrode2)

+ (1/Cvib) (formula 3).

By formula (2) and formula (3), (A) of Fig. 4 also can represent as Fig. 4 (B).

Flexibility Cact is illustrated in the volume of the medium that can bear when exerting pressure on the unit area.That is, flexibility Cact represents the easy degree of being out of shape.

(C) of Fig. 4 shows and fully stored liquid in the container body of print cartridge 7, and the sectional view of the liquid-detecting 60 of liquid when filling with to the oscillating component 61 of liquid-detecting 60 peripheral.M ' the max of Fig. 4 (C) is illustrated in the container body of print cartridge 7 and has fully stored liquid, and the additional inertial of liquid when filling with to the oscillating component 61 of liquid-detecting 60 peripheral (additional mass (quality that the vibration of vibration area is exerted an influence) divided by area square and obtain) maximal value.M ' max can represent with following formula:

M ' max=(π * ρ/(2*k ³)) * (2* (2*k*a) ³/ (2* π))/(π * a ²) ²(formula 4),

(a is that radius, the ρ of oscillating component is that density of medium, k are wave number).

In addition, formula 4 is that radius is set up when being a circular at the oscillating component 61 of liquid-detecting 60.Additional inertial M ' is expression by being positioned at the amount that quality that near the oscillating component 61 media make oscillating component 61 increases on apparent.By formula 4 as can be known, M ' max significantly changes according to the radius a of oscillating component 61 and density of medium ρ.

Wave number k can be represented by the formula:

K=2* π * fact/c (formula 5),

(fact is the resonant frequency of oscillating component 61.C is the speed of the sound propagated in medium).

(D) of Fig. 4 shows the oscillating component 61 of the liquid-detecting 60 under the situation of (C) of Fig. 4 and the equivalent circuit in chamber 43, the situation of wherein said Fig. 4 (C) is meant and has fully stored liquid in the container body of print cartridge 7, and liquid is filled with to the periphery of the oscillating component 61 of liquid-detecting 60.

(E) of Fig. 4 shows the sectional view of liquid-detecting 60 under the following situation, described situation is meant, though the liquid of the container body of print cartridge 7 is consumed, the periphery of the oscillating component 61 of liquid-detecting 60 does not have liquid, the chamber 43 interior residual liquid that have of liquid-detecting 60.

Formula 4 is to be illustrated in when having filled with liquid in the container body of print cartridge 7, the formula of the maximum inertia M ' max that is determined by the density p of ink etc.On the other hand, liquid in container body is consumed, and when the residual liquid that is in oscillating component 61 peripheries of liquid-detecting 60 when liquid is arranged had been replaced by gas or vacuum in chamber 43, additional inertial M ' generally was represented as (more specifically please refer to aftermentioned formula 8):

M '=ρ * t/S (formula 6).

Here, t is the thickness of the medium of participation vibration.S is the area of the oscillating component 61 of liquid-detecting 60.When oscillating component 61 is radiuses when being a circular, S=π * a ²

Therefore, fully stored liquid in container body, and liquid is when filling with to the oscillating component 61 of liquid-detecting 60 peripheral, additional inertial M ' calculates according to formula 4.And be consumed when liquid, and the liquid of periphery that is in the oscillating component 61 of liquid-detecting 60 chamber 43 in the residual liquid has been when being replaced by gas or vacuum, and it is according to formula 6 calculating.

Here, as Fig. 4 (E), when though the liquid of the container body of print cartridge 7 is consumed, thereby the periphery of the oscillating component 61 of liquid-detecting 60 does not have liquid, but it is also residual when liquid is arranged in the chamber 43 of liquid-detecting 60, for convenience, in the case additional inertial M ' is taken as M ' cav, thereby the additional inertial M ' max when having filled with liquid around the oscillating component 61 of liquid-detecting 60 distinguishes.

(F) of Fig. 4 is illustrated in the oscillating component 61 of the liquid-detecting 60 under the situation of (E) of Fig. 4 and the equivalent circuit in chamber 43, (E) of wherein said Fig. 4 though situation be meant that the liquid of the container body of print cartridge 7 is consumed, thereby the periphery of the oscillating component 61 of liquid-detecting 60 does not have liquid, but also residual in the chamber 43 of liquid-detecting 60 liquid is arranged.

Here, in formula 6 thickness t of density of medium ρ and medium with the related parameter of the state of medium.When fully having stored liquid in container body, liquid contacts with the oscillating component 61 of liquid-detecting 60.On the other hand, when in container body, not having abundant storaging liquid, the 43 inner residual liquid that have in the chamber, perhaps the oscillating component 61 of liquid-detecting 60 contacts with gas or vacuum.Liquid at the periphery of liquid-detecting 60 is consumed, thereby turn to the additional inertial M ' var the process of M ' cav of (E) of Fig. 4 to change along with the variation of the thickness t of density of medium ρ and medium from the M ' max of Fig. 4 (C), the thickness t of wherein said density of medium ρ and medium changes according to the storing state of the liquid in the container body.Thus, resonant frequency fs also changes.Therefore, by determining that resonant frequency fs can detect the amount of the liquid in the container body.

Here, shown in Fig. 4 (E), when t=d, if utilize formula 6 to represent M ' cav, then among the t with the depth d substitution formula 6 in chamber, so have:

M ' cav=ρ * d/S (formula 7).

In addition, if the medium mutually different liquid that is kind is then also different according to the different densities ρ that forms, thereby additional inertial M ' and resonant frequency fs are also different.Therefore, by determining that resonant frequency fs can detect the kind of liquid.

Fig. 5 A is the curve that concerns between the resonant frequency fs of the amount of ink in the container body of expression print cartridge 7 and ink and oscillating component.The longitudinal axis is represented resonant frequency fs, and transverse axis is represented quantity of ink.

Fully stored ink in the container body of print cartridge 7, and the periphery of the oscillating component 61 of liquid-detecting 60 has been when having filled with ink, this maximum additional inertial M ' max is the represented value of formula 4.On the other hand, when ink is consumed, and when ink was not filled with to the oscillating component 61 of liquid-detecting 60 peripheral when having ink residual in chamber 43, additional inertial M ' var can be calculated by formula 6 based on the thickness t of medium.Because the t in the formula 6 is the thickness that participates in the medium of vibration, so depth d in the chamber 43 of the liquid-detecting 60 by reducing residual ink, just make the thickness of substrate 41 enough thin, also can the process that ink consumes gradually be detected (with reference to (C) of Fig. 4).Here establish the thickness of tink, establish tink-max and be the tink among the M ' max for the ink that participates in vibration.

For example, liquid-detecting 60 with respect to the liquid level approximate horizontal of ink be configured on the bottom surface of print cartridge.At this moment, if ink is consumed, the liquid level of ink becomes the height of tink-max when following from liquid-detecting 60, and M ' var gradually changes according to formula 6, and resonant frequency fs gradually changes according to formula 1.Therefore, as long as the liquid level t of ink is in the scope of t, liquid level sensor 60 just can detect the consumption state of ink gradually.

Perhaps, liquid-detecting 60 is located vertically on the sidewall of print cartridge substantially with the liquid level of ink.At this moment, when ink is consumed, when the liquid level of ink arrived the oscillating component 61 of liquid-detecting 60, additional inertial M ' reduced along with the reduction of liquid level.Thus, resonant frequency fs increases gradually according to formula 1.Therefore, as long as the liquid level of ink is in the scope of diameter 2a (with reference to (C) of Fig. 4) in chamber 43, liquid-detecting 60 just can detect the consumption state of ink gradually.

What the curve X of Fig. 5 A represented is, when the chamber 43 of the liquid-detecting 60 on being disposed at the bottom surface is enough shallow, perhaps be disposed at the oscillating component 61 of the liquid-detecting 60 on the sidewall when enough big or long, the relation in the container body between the resonant frequency fs of the amount of stored ink and ink and oscillating component 61.Thereby be appreciated that in the quantity of ink minimizing in container body the state that the resonant frequency fs of ink and oscillating component 61 slowly changes.

In more detail, when what is called can detect the process that ink is consumed gradually, be meant the periphery at the oscillating component 61 of liquid-detecting 60, mutually different liquid of density and gas exist simultaneously and participate in vibration time.Along with ink is consumed gradually, for the medium that participates in vibration at the periphery of the oscillating component 61 of liquid-detecting 60, liquid reduces and gas increases.

For example, when liquid-detecting 60 is disposed with respect to liquid level, at t ink during less than tink-max, the medium of the participation of liquid-detecting 60 vibration comprise ink and gas the two.Therefore,, come the state below the M ' max of representation formula 4 with the additional mass of ink and gas if utilize the area S of the oscillating component 61 of liquid-detecting 60, then:

M '=M ' air+M ' ink=ρ air*t air/S+ ρ ink*t ink/S (formula 8).

Here, M ' air is the inertia of air, and M ' ink is the inertia of ink.ρ air is the density of air, and ρ ink is the density of ink.Tair is the thickness of the air of participation vibration, and tink is the thickness of the ink of participation vibration.

In the medium of the participation vibration on the periphery of the oscillating component 61 of liquid-detecting 60, along with liquid reduces and gas increases, when liquid-detecting 60 with respect to the liquid level of ink during by the configuration of approximate horizontal ground, tair increases, and tink reduces.Thus, M ' var reduces gradually, and resonant frequency increases gradually.Thereby, can detect the amount or the consumed ink amount that residue in the ink in the container body.In addition, why have only density of liquid in formula 7, be because hypothesis is compared with density of liquid, the density of air is little to have arrived negligible degree.

When liquid-detecting 60 with respect to the liquid level of ink during by arranged perpendicular, can think: in the oscillating component 61 of liquid-detecting 60, the medium of the participation of liquid-detecting 60 vibration is that the medium of the participation vibration of the zone of ink and liquid-detecting 60 is only arranged is the equivalent circuit (not shown) regional arranged side by side that gas is only arranged.The area in the zone of ink is only arranged is Sink if establish the medium of the participation vibration of liquid-detecting 60 and be, the medium of establishing the participation vibration of liquid-detecting 60 is that the area in the zone of gas is only arranged is Sair, then:

1/M’＝1/M’air+1/M’ink＝S?air/(ρair*t?air)+S?ink/(ρink*t?ink)

(formula 9).

In addition, formula 9 is applicable to the situation of not preserving ink in the chamber 43 of liquid-detecting 60.Additional inertial about under the situation of preserving ink in the chamber 43 of liquid-detecting 60 can calculate by the M ' of formula 9 and M ' the cav sum of formula 7.

Since the vibration of the oscillating component 61 of liquid-detecting 60 from the change in depth of tink-max to the residual depth d of ink, so when liquid-detecting 60 being disposed at the bottom surface, then can't detect the process that ink reduces gradually with the slightly little degree of the residual depth ratio tink-max of ink.At this moment, the vibration of the liquid-detecting changing according to the slight quantity of ink till from tink-max to residual depth d changes, and detects quantity of ink and changes.In addition, be configured in the side, and under the very little situation of the diameter in chamber 43 because that the vibration by the liquid-detecting 60 between the chamber 43 changes is very slight, so be difficult to detect quantity of ink by process, detection be that ink level is than chamber 43 height or low.

Relation between the quantity of ink in container body when for example, the curve Y of Fig. 5 A shows oscillating component 61 and forms the vibration area of small circular and the resonant frequency fs of ink and oscillating component 61.Between the difference Q of the quantity of ink the during front and back of the liquid level that shows the ink in container body by the installation site of liquid-detecting 60, the resonant frequency fs state jumpy of ink and oscillating component 61.Thus, because the ink of scheduled volume that whether can detect to binaryzation in container body remnants, so can carry out high-precision test.

The method of utilizing liquid-detecting 60 to detect no liquid like this has or not ink owing to can directly contacting to detect by oscillating component 61 and ink, so compare the accuracy of detection height with the method for calculating consumed ink amount by software.In addition, utilize electrode to detect the method that has or not ink and may be subjected to the installation site of container body top electrode and the influence of ink kind, but the method for utilizing liquid-detecting 60 to detect no liquid then is difficult to be subjected to the installation site of liquid-detecting 60 on the container body and the influence of ink kind by electric conductivity.

In addition, detect the two with liquid,, can reduce the number that is installed in the sensor on the container body so compare with utilizing different sensors to implement to vibrate the method that detects with liquid owing to can utilize single liquid-detecting 60 to implement vibration.Therefore, can make print cartridge 7 at an easy rate with liquid measure measuring ability.In addition, preferably the vibration frequency with piezoelectric layer 47 is made as non-zone of audibility, thereby makes the sound peace and quiet that produced in the middle of liquid-detecting 60 work.

Fig. 5 B shows an example that concerns between the resonant frequency fs of the density of ink and ink and oscillating component 61.Here, " ink is full " do not mean two relative states with " ink sky " (perhaps " ink has "), and do not mean so-called ink full state and ink spent condition.Shown in Fig. 5 B, when ink density is very high, because additional inertial is very big, so resonant frequency fs reduces.That is, resonant frequency is according to the difference of ink kind and difference.Therefore, by measuring resonant frequency fs, when filling ink once more, can confirm whether to sneak into the different ink of density.That is, can discern the print cartridge 7 that has stored the mutually different ink of kind.

Then, set the size and the shape in chamber 43,, the condition that can correctly detect liquid condition at this moment is described in detail even make in the chamber 43 of liquid-detecting 60 when liquid in the container body of print cartridge 7 be empty state also residual liquid.If liquid-detecting 60 can detect the state of liquid when being full of liquid in chamber 43, also can detect the state of liquid when then in chamber 43, not having full of liquid.

Resonant frequency fs is the function of inertia M.Inertia M is the inertia Mact and the additional inertial M ' sum of oscillating component 61.Here, additional inertial M ' has relation with the state of liquid.Additional inertial M ' is that expression is by being in the apparent amount that increases that goes up of quality that near oscillating component 61 media make oscillating component 61.Just, by the vibration of oscillating component 61 on apparent the recruitment of the quality of the caused oscillating component 61 of absorbing medium (the inertia increase relevant) with vibration.

Therefore, when M ' cav was bigger than the M ' max in the formula 4, the apparent medium that absorbs of going up all was the liquid that residues in the chamber 43.Thereby, identical with the state that is full of medium in the container body.At this moment, since the medium that participates in vibration less than M ' max, so can't detect its variation even ink has been consumed also.

On the other hand, as M ' cav during less than the M ' max in the formula 4, the apparent medium that absorbs of going up is liquid residual in the chamber 43 and gas or the vacuum in the container body.Because this moment is different with the state that has been full of liquid in container body, M ' changes, so resonant frequency fs also changes.Therefore, liquid-detecting 60 can detect the state of the liquid in the container body.

That is, the liquid in the container body of print cartridge 7 is under the empty state, and when residual when liquid is arranged in the chamber 43 of liquid-detecting 60, the condition that liquid-detecting 60 can correctly detect liquid condition is that M ' cav is littler than M ' max.In addition, the condition that liquid-detecting 60 can correctly detect liquid condition is M ' max＞M ' cav, and is irrelevant with the shape in chamber 43.

Here, M ' cav is the quality inertia with the liquid of the capacity capacity about equally in chamber 43.Therefore, according to the inequality of M ' max＞M ' cav, the condition that liquid-detecting 60 can correctly detect liquid condition can be expressed as the condition of the capacity in chamber 43.For example, be a if establish the radius in circular chamber 43, the degree of depth of establishing chamber 43 is d, then has:

M ' max＞ρ * d/ π a ²(formula 10).

Behind the expansion formula 10, can obtain following condition:

A/d＞3* π/8 (formula 11).

Therefore, if have the radius a of opening 161 and the depth d in chamber 43 satisfies the liquid-detecting 60 in the chamber 43 of formula 11, then the liquid in the container body be the state of sky, even and when residual when liquid is arranged in the chamber 43, detect the state of liquid with also can having no misoperation.

In addition, formula 10, formula 11 only in the chamber 43 be shaped as circle the time set up.When the shape in chamber 43 is not circle, if utilize the formula of corresponding M ' max, with the π a in the formula 10 ²Replace to its area and calculate, but the relation of the width of export cavity 43 and the length equidimension and the degree of depth then.

In addition, because additional inertial M ' also exerts an influence to the acoustic impedance characteristic,, detect because residual vibration and the method for the back electromotive force that produces in liquid-detecting 60 can detect the variation of acoustic impedance at least so also we can say.

Fig. 6 A and Fig. 6 B show to liquid-detecting 60 thereby the waveform that drive signal makes oscillating component 61 residual vibration (free vibration) after forcing to drive, liquid-detecting 60 and the measuring method of residual vibration are provided.Can detect by the frequency change or the oscillation amplitude change of the residual vibration after the piezoelectric element of liquid-detecting 60 in the installation site level of the liquid-detecting 60 of liquid level in print cartridge 7 being or down.Among Fig. 6 A and Fig. 6 B, the longitudinal axis is represented the voltage of the back electromotive force that the residual vibration owing to liquid-detecting 60 produces, transverse axis express time.By the residual vibration of liquid-detecting 60, can shown in Fig. 6 A and Fig. 6 B, produce the waveform of the simulating signal of voltage like that.Then, with the frequency corresponding digital numerical value (binaryzation) of analog signal conversion one-tenth with signal.In the example shown in Fig. 6 A and Fig. 6 B, measure the time that produces from four pulses between eight pulses of the 4th pulse to the of simulating signal.

More particularly, after liquid-detecting 60 vibrations, predefined predetermined reference voltage is counted to the number of times that high-voltage side crosses from low voltage side.Then, generate and to make count value 4 to be the digital signal of high level between the count value 8, and by predetermined time clock measurement from count value 4 to count value time of 8.

Waveform when Fig. 6 A is the liquid level installation site level that is in liquid-detecting 60 upper.Waveform when on the contrary, Fig. 6 B is the liquid level installation site level that is in liquid-detecting 60 the next.Fig. 6 A and Fig. 6 B are compared, find that Fig. 6 A is longer than Fig. 6 B for the time till 8 from count value 4 to count value.In other words, have or not ink on the installation site level according to liquid-detecting 60,8 needed times are also different from count value 4 to count value.Utilize the difference of this required time, can detect the consumption state of ink.

Why the 4th count value from analog waveform begins counting, is in order to begin measurement again after the residual vibration (free vibration) of liquid-detecting 60 is stable.Since the 4th count value counting only is an example, also can begin counting from any count value.Here, detect signal, and measure from the time of eight count values of the 4th count value to the by predetermined time clock from eight count values of the 4th count value to the.Can obtain resonant frequency based on this time.Time clock need not measure the time of the 8th pulse, also can be to count down to count value arbitrarily.In Fig. 6 A and Fig. 6 B,,, also can detect the interior at interval time of different count values according to the circuit structure that detects frequency though be the time of measuring eight count values of the 4th count value to the.

For example, thus when the change of the amplitude of the stay in grade peak value of ink is very little,, also can obtain resonant frequency by the time of detecting six count values of the 4th count value to the in order to improve the speed of detection.In addition, thus when the change of the amplitude of the quality instability pulse of ink is very big,, also can detect the time of 12 count values of the 4th count value to for the correct residual vibration that detects.

Fig. 7 is the skeleton view of expression structure that liquid-detecting 60 is formed as mounting module body 100.Module body 100 is installed in the predetermined part of the container body of print cartridge 7.Module body 100 is constituted as: detect by the variation to the acoustic impedance at least of the medium in the container body, can detect the consumption state of the liquid in the container body.

The module body 100 of present embodiment has and is used for liquid-detecting 60 is installed in container installation portion 101 on the container body.Container installation portion 101 has the plane and is roughly the base station 102 of rectangle and the columnar portion 116 on the base station 102, and described columnar portion 116 is used to hold the liquid-detecting 60 that vibrates by drive signal.In addition, module body 100 is constituted as when it is installed on the print cartridge 7, can't be from the liquid-detecting 60 of outside contact modules body 100.Thus, can protect liquid-detecting 60 to avoid outside contact.In addition, the tip side edge of columnar portion 116 has circular arc, thereby embeds easily when its hole on being formed at print cartridge 7 is installed.

Fig. 8 is the exploded view of module body 100 shown in Figure 7.Module body 100 comprises the container installation portion 101 that is formed by resin and has disc 110 and the device installation portion 105 of recess 113 (with reference to Fig. 7).In addition, module body 100 has lead-in

wire

104a and 104b, liquid-detecting 60 and film 108.The material that disc 110 preferably is difficult to get rusty by stainless steel or stainless steel alloy etc. forms.

Columnar portion 116 and base station 102 included in the container installation portion 101 form peristome 114 at core, so that can hold lead-in

wire

104a and 104b, and around peristome 114, form recess 113, so as can receiving fluids pick-up unit 60, film 108 and disc 110.

Liquid-detecting 60 engages with disc 110 by film 108, and disc 110 and liquid-detecting 60 are fixed in the recess 113 (container installation portion 101).Therefore, lead-in

wire

104a and 104b, liquid-detecting 60, film 108 and disc 110 are installed in the container installation portion 101 as one.

Lead-in

wire

104a and 104b combine with the upper electrode terminal 45 and the lower electrode terminal 44 of liquid-detecting 60 respectively, thereby transmit drive signals (driving pulse) to piezoelectric layer 47, and the signal of the resonant frequency that liquid-detecting 60 is detected passes to pen recorder etc.

Liquid-detecting 60 vibrates provisionally according to transmitting the drive signal of coming from lead-in wire 104a and 104b.In addition, liquid-detecting 60 carries out residual vibration after vibration, and produces back electromotive force by this vibration.At this moment, by detecting the vibration period of back emf waveform, can detect with container body in the corresponding resonant frequency of liquid consumption state.

Film 108 is bonding with liquid-detecting 60 and disc 110, thereby makes liquid-detecting 60 hydraulic seals.Film 108 is preferably formed by polyolefin etc., and carries out bonding with thermal weld.By film 108 that liquid-detecting 60 and disc 110 is planar bonding and fixing, thus the deviation of bond locations eliminated, make that the part outside the oscillating component is not vibrated.Therefore, even liquid-detecting 60 and disc 110 is bonding, the vibration characteristics of liquid-detecting 60 can not change yet.

In addition, disc 110 is circular, and the peristome 114 of base station 102 forms cylindrical shape.Liquid-detecting 60 and film 108 are formed rectangle.Lead-in

wire

104a and 104b, liquid-detecting 60, film 108 and disc 110 can be loaded and unloaded with respect to base station 102.Base station 102, lead-in

wire

104a and 104b, liquid-detecting 60, film 108 and disc 110 are with respect to the central shaft balanced configuration of module body 100.In addition, the center of base station 102, liquid-detecting 60, film 108 and disc 110 is configured on the approximate centre axle of module body 100.

In addition, the area of the peristome 114 of base station 102 is formed bigger than the area of the vibration area of liquid-detecting 60.The oscillating component of the center of disc 110 and liquid-detecting 60 over against the position on be formed with through hole 112.To shown in Figure 4, in liquid-detecting 60, be formed with chamber 43 as Fig. 2, and through hole 112 and the chamber 43 common ink storage portions that form.In order to reduce the influence of residual ink, the diameter that the thickness of disc 110 cans be compared to through hole 112 most is little.For example, the degree of depth of through hole 112 size below 1/3rd of its diameter preferably.Through hole 112 is with respect to the axisymmetric sub-circular in the center of module body 100.In addition, the area of through hole 112 is bigger than the aperture area in the chamber 43 of liquid-detecting 60.The edge in the cross section of through hole 112 can be taper, also can be stepped appearance.

Module body 100 is installed in sidepiece, top or the bottom of container body, and makes the inboard of through hole 112 towards container body.When ink is consumed, when liquid-detecting 60 peripheries did not have ink, the variation of resonant frequency of liquid-detecting 60 was very big, can detect the liquid level change of ink in view of the above.

Fig. 9 is near the sectional view the bottom when container body 7a that module body shown in Figure 7 100 is installed to print cartridge 7 is gone up, container body 7a.Module body 100 is installed in the through hole on the sidewall that is formed at container body 7a.On the composition surface of the sidewall of container body 7a and module body 100, be provided with O shape ring 90, keep the close property of liquid between module body 100 and the container body 7a.In order so to seal with O shape ring 90, module body 100 preferably is furnished with the described columnar portion of Fig. 7.

The top of module body 100 is exposed among the ink storage area 7b of container body 7a, thereby passes through the through hole 112 of disc 110, and the ink in the container body 7a contacts with liquid-detecting 60.According to liquid detect adorn 60 oscillating component around be liquid or gas, the resonant frequency difference of the residual vibration of liquid-detecting 60, thereby can utilize module body 100 to detect the consumption state of ink.

Then, with reference to accompanying drawing the liquid-detecting of other embodiments of the present invention and the print cartridge (liquid container) of being furnished with this liquid-detecting are described.

Figure 10, Figure 11 A and Figure 11 B are the synoptic diagram of the liquid-detecting 260 of present embodiment, this liquid-detecting 260 has the base portion 240 that stacked oscillating plate 242 constitutes on substrate 241, and this base portion 240 has first 240a respect to one another and second 240b.Be formed with circular chamber (recess) 243 in base portion 240, be used to admit the medium as detected object, and this chamber 243 is at first 240a one side opening, the bottom surface sections 243a in chamber 243 is formed can be by oscillating plate 242 vibrations.In other words, the part of actual vibration has been stipulated its profile by chamber 243 in the whole oscillating plate 242.Two ends in second 240b one side of base portion 240 are formed with lower electrode terminal 244 and upper electrode terminal 245.

On second 240b of base portion 240, be formed with lower electrode (first electrode) 246, this lower electrode 246 has circular main part 246a and extension 246b, and this extension 246b is connected to the direction extension of bottom electrode terminal 244 and with lower electrode terminal 244 from main part 246a.The center of the circular body part 246a of lower electrode 246 is consistent with the center in chamber 243.

It is bigger than circular cavity 243 that the circular body part 246a of lower electrode 246 is formed diameter, and cover all zones corresponding with chamber 243.

Stacked piezoelectric layer 247 on lower electrode 246, this piezoelectric layer 247 has the diameter circular body part 247a littler than chamber 243, and extension 247b, described extension 247b extends out and crosses and corresponding position, the edge in chamber 243 from this main part 247a, extends to the outside with the corresponding zone, bottom surface in chamber 243 always.

Be laminated with the main part 249a of the circle of upper electrode (second electrode) 249 on piezoelectric layer 247, it is littler than the main part 247a of piezoelectric layer 247 that the main part 249a of this upper electrode 249 is formed diameter.In addition, upper electrode 249 has extension 249b, and this extension 249b extends out from main part 249a, and the extension 247b of extend past piezoelectric layer 247 top extends to the outside with the corresponding zone, bottom surface in chamber 243 always.This extension 249b extends across the extension 247b of piezoelectric layer 247, and is connected with upper electrode terminal 245.

So, the main part 247a of piezoelectric layer 247 becomes the structure that is clipped in the middle by the main part 246a of the main part 249a of upper electrode 249 and lower electrode 246.Thus, can be out of shape driving piezoelectric layer 247 effectively.

As mentioned above, to be formed diameter littler than the main part 247a of piezoelectric layer 247 for the main part 249a of upper electrode 249.On the other hand, the main part 246a of lower electrode 246 is covered with whole of main part 247a of piezoelectric layer 247.Therefore, the main part 249a of upper electrode 249 has determined to produce in the whole piezoelectric layer 247 scope of the part of piezoelectric effect.

In addition, the parts that are contained in the liquid-detecting 260 preferably form as one mutually by sintering.By forming liquid-detecting 260 like this, can make the utilization of liquid-detecting 260 become easy.

The material of piezoelectric layer 247 preferably uses lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT) or does not use plumbous leadless piezoelectric film.The material of substrate 241 preferably uses zirconia or aluminium oxide.In addition, oscillating plate 242 preferably uses and substrate 241 identical materials.Upper electrode 249, lower electrode 246, upper electrode terminal 245 and lower electrode terminal 244 can use the material with electric conductivity, for example use metals such as gold, silver, copper, platinum, aluminium, nickel.

About the main part 247a of piezoelectric layer 247, the main part 249a of upper electrode 249 and the main part 246a of lower electrode 246, their center is consistent with the center in chamber 243.In addition, but determine oscillating plate 242 oscillating component circle chamber 243 be centered close to whole liquid pick-up unit 260 in the heart.

But constituted the oscillating component 261 of liquid-detecting 260 with the corresponding part in chamber 243 by the main part 247a of part corresponding among the main part 246a of the oscillating component of the oscillating plate 242 of chamber 243 regulation, lower electrode 246, piezoelectric layer 247 and extension 247b and main part 249a corresponding part in chamber 243 and upper electrode 249 and extension 249b with chamber 243.In addition, the center of the oscillating component 261 of this liquid-detecting 260 is consistent with the center of liquid-detecting 260.

In addition, but the oscillating component of the main part 246a of the main part 249a of the main part 247a of piezoelectric layer 247, upper electrode 249, lower electrode 246 and oscillating plate 242 (promptly corresponding with the bottom surface portions 243a in chamber 243 part) has circular shape, thereby the oscillating component 261 of liquid-detecting 260 is shapes symmetrical substantially with respect to the center of liquid-detecting 260.

So, in the present embodiment, owing to cover the corresponding zone in whole and chamber 243 with the main part 246a of lower electrode 246, thus compared with the past, the difference between the deformation pattern when deformation pattern when having reduced forced vibration and free vibration.In addition, because the oscillating component 261 of liquid-detecting 260 is shapes symmetrical substantially with respect to the center of liquid-detecting 260, so from this center, the rigidity of described oscillating component 261 is isotropy substantially.

Therefore, suppressed generation owing to the unnecessary vibration that produces of asymmetry of structure, and when having prevented owing to forced vibration and the output reduction of the back electromotive force that the difference of the deformation pattern between the two causes during free vibration.Thus, the accuracy of detection of the resonant frequency of the residual vibration in the oscillating component 261 of liquid-detecting 260 is improved, and the detection of the residual vibration of oscillating component 261 also becomes easy.

In addition, owing to cover the corresponding zone in whole and chamber 243 with the main part 246a of the diameter lower electrode 246 bigger than chamber 243, so can prevent the unnecessary generation of vibration that the position deviation of lower electrode 246 causes owing to making, thereby can prevent the reduction of accuracy of detection.

In addition, because the scope that the oscillating component 261 of liquid-detecting 260 contacts with liquid is only limited to chamber 243 existing scopes,, thus, can detect the ink level in the print cartridge 7 accurately so can accurately carry out the detection of liquid.

As a variation of present embodiment, also can insulation course 250 be clipped between the extension 249b and piezoelectric layer 247 of upper electrode 249 as shown in Figure 12.Because the existence of this insulation course 250, make the scope of the part that produces piezoelectric effect in the whole piezoelectric layer 247 for circular, thereby its symmetry improve, and can further suppress unnecessary generation of vibration thus.

Figure 13, Figure 14 A and Figure 14 B are the synoptic diagram of the liquid-detecting 360 of present embodiment, this liquid-detecting 360 has stacked oscillating plate 342 on substrate 341 and the base portion 340 of formation, and this base portion 340 has first 340a respect to one another and second 340b.Be formed with circular chamber (recess) 343 in base portion 340, be used to admit the medium as detected object, and this chamber 343 is at first 340a one side opening, the bottom surface sections 343a in chamber 343 is formed can be by oscillating plate 342 vibrations.In other words, the part of actual vibration has been stipulated its profile by chamber 343 in the whole oscillating plate 342.Two ends in second 340b one side of base portion 340 are formed with lower electrode terminal 344 and upper electrode terminal 345.

On second 340b of base portion 340, be formed with lower electrode (first electrode) 346, this lower electrode 346 has circular main part 346a and extension 346b, and this extension 346b is connected to the direction extension of bottom electrode terminal 344 and with lower electrode terminal 344 from this main part 346a.The center of the circular body part 346a of lower electrode 346 is consistent with the center in chamber 343.

It is bigger than circular cavity 343 that the circular body part 346a of lower electrode 346 is formed diameter, and cover all zones corresponding with chamber 343.

Stacked piezoelectric layer 347 on lower electrode 346, this piezoelectric layer 347 have circular main part 347a and extension 347b, and it is bigger than chamber 343 that wherein said main part 347a is formed diameter, thereby cover the corresponding zone in whole and chamber 343; Described extension 347b extends out from described main part 347a.

Be laminated with the main part 349a of the circle of upper electrode (second electrode) 349 on piezoelectric layer 347, it is littler than chamber 343 that the main part 349a of this upper electrode 349 is formed diameter, thereby be configured in the inside in the zone corresponding with chamber 343.In addition, upper electrode 349 has extension 349b, and this extension 349b extends out from main part 349a, the main part 347a of extend past piezoelectric layer 347 and extension 347b top.This extension 349b extends across the extension 347b of piezoelectric layer 347, and is connected with upper electrode terminal 345.

So, the main part 347a of piezoelectric layer 347 becomes the structure that is clipped in the middle by the main part 346a of the main part 349a of upper electrode 349 and lower electrode 346.Thus, can be out of shape driving piezoelectric layer 347 effectively.

As mentioned above, to be formed diameter littler than the main part 347a of piezoelectric layer 347 for the main part 349a of upper electrode 349.On the other hand, the main part 346a of lower electrode 346 is covered with whole of main part 347a of piezoelectric layer 347.Therefore, the main part 349a of upper electrode 349 has determined to produce in the whole piezoelectric layer 347 scope of the part of piezoelectric effect.

In addition, the parts that are contained in the liquid-detecting 360 preferably form as one mutually by sintering.By forming liquid-detecting 360 like this, can make the utilization of liquid-detecting 360 become easy.

The material of piezoelectric layer 347 preferably uses lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT) or does not use plumbous leadless piezoelectric film.The material of substrate 341 preferably uses zirconia or aluminium oxide.In addition, oscillating plate 342 preferably uses and substrate 341 identical materials.Upper electrode 349, lower electrode 346, upper electrode terminal 345 and lower electrode terminal 344 can use the material with electric conductivity, for example use metals such as gold, silver, copper, platinum, aluminium, nickel.

About the main part 347a of piezoelectric layer 347, the main part 349a of upper electrode 349 and the main part 346a of lower electrode 346, their center is consistent with the center in chamber 343.In addition, but determine oscillating plate 342 oscillating component circle chamber 343 be centered close to whole liquid pick-up unit 360 in the heart.

But constituted the oscillating component 361 of liquid-detecting 360 with the corresponding part in chamber 343 by the main part 349a of corresponding part in the main part 347a of part corresponding among the main part 346a of the oscillating component of the oscillating plate 342 of chamber 343 regulation, lower electrode 346, piezoelectric layer 347 and chamber 343 and upper electrode 349 and extension 349b with chamber 343.In addition, the center of the oscillating component 361 of this liquid-detecting 360 is consistent with the center of liquid-detecting 360.

In addition, but the oscillating component of the main part 346a of the main part 349a of the main part 347a of piezoelectric layer 347, upper electrode 349, lower electrode 346 and oscillating plate 342 (promptly corresponding with the bottom surface portions 343a in chamber 343 part) has circular shape, thereby the oscillating component 361 of liquid-detecting 360 is shapes symmetrical substantially with respect to the center of liquid-detecting 360.

So, in the present embodiment, since cover the corresponding zone in whole and chamber 343 with the main part 347a of the main part 346a of lower electrode 346 and piezoelectric layer 347, thus compared with the past, the difference between the deformation pattern when deformation pattern when having reduced forced vibration and free vibration.In addition, because the oscillating component 361 of liquid-detecting 360 is shapes symmetrical substantially with respect to the center of liquid-detecting 360, so from this center, the rigidity of described oscillating component 361 is isotropy substantially.

Therefore, suppressed generation owing to the unnecessary vibration that produces of asymmetry of structure, and when having prevented owing to forced vibration and the output reduction of the back electromotive force that the difference of the deformation pattern between the two causes during free vibration.Thus, the accuracy of detection of the resonant frequency of the residual vibration in the oscillating component 361 of liquid-detecting 360 is improved, and the detection of the residual vibration of oscillating component 361 also becomes easy.

In addition, owing to cover the corresponding zone in whole and chamber 343 with the main part 346a of the diameter lower electrode 346 bigger than chamber 343, so can prevent the unnecessary generation of vibration that the position deviation of lower electrode 346 causes owing to making, thereby can prevent the reduction of accuracy of detection.

In addition, because the scope that the oscillating component 361 of liquid-detecting 360 contacts with liquid is only limited to chamber 343 existing scopes,, thus, can detect the ink level in the print cartridge 7 accurately so can accurately carry out the detection of liquid.

As a variation of present embodiment, also can insulation course 350 be clipped between the extension 349b and piezoelectric layer 347 of upper electrode 349 as shown in Figure 15.Because the existence of this insulation course 350, make the scope of the part that produces piezoelectric effect in the whole piezoelectric layer 347 for circular, thereby its symmetry improve, and can further suppress unnecessary generation of vibration thus.

Figure 16, Figure 17 A and Figure 17 B are the synoptic diagram of the liquid-detecting 460 of present embodiment, this liquid-detecting 460 has stacked oscillating plate 442 on substrate 441 and the base portion 440 of formation, and this base portion 440 has first 440a respect to one another and second 440b.Be formed with circular chamber (recess) 443 in base portion 440, be used to admit the medium as detected object, and this chamber 443 is at first 440a one side opening, the bottom surface sections 443a in chamber 443 is formed can be by oscillating plate 442 vibrations.In other words, the part of actual vibration has been stipulated its profile by chamber 443 in the whole oscillating plate 442.Two ends in second 440b one side of base portion 440 are formed with lower electrode terminal 444 and upper electrode terminal 445.

On second 440b of base portion 440, be formed with lower electrode (first electrode) 446, this lower electrode 446 has circular main part 446a and extension 446b, and this extension 446b is connected to the direction extension of bottom electrode terminal 444 and with lower electrode terminal 444 from this main part 446a.The center of the circular body part 446a of lower electrode 446 is consistent with the center in chamber 443.

It is littler than circular cavity 443 that the circular body part 446a of lower electrode 446 is formed diameter, thereby be configured in the inside in the zone corresponding with chamber 443.The diameter of the main part 446a of lower electrode 446 is preferably the size more than 75% of the diameter in chamber 443.

The main part 447a of the circle of stacked piezoelectric layer 447 on the main part 446a of lower electrode 446, and the main part 447a of this piezoelectric layer 447 to be formed diameter littler than the main part 446a of lower electrode 446.Extend extension 447b from the main part 447a of piezoelectric layer 447, the extension 447b of this piezoelectric layer 447 extends to the outside in the zone corresponding with chamber 443 always.

Be laminated with the main part 449a of the circle of upper electrode (second electrode) 449 on the main part 447a of piezoelectric layer 447, it is littler than the main part 447a of piezoelectric layer 447 that the main part 449a of this upper electrode 449 is formed diameter.In addition, upper electrode 449 has extension 449b, and this extension 449b extends out from main part 449a, and the main part 447a of extend past piezoelectric layer 447 and extension 447b top.This extension 449b extends across the extension 447b of piezoelectric layer 447, and is connected with upper electrode terminal 445.

So, the main part 447a of piezoelectric layer 447 becomes the structure that is clipped in the middle by the main part 446a of the main part 449a of upper electrode 449 and lower electrode 446.Thus, can be out of shape driving piezoelectric layer 447 effectively.

As mentioned above, to be formed diameter littler than the main part 447a of piezoelectric layer 447 for the main part 449a of upper electrode 449.On the other hand, the main part 446a of lower electrode 446 is covered with whole of main part 447a of piezoelectric layer 447.Therefore, the main part 449a of upper electrode 449 has determined to produce in the whole piezoelectric layer 447 scope of the part of piezoelectric effect.

In addition, the parts that are contained in the liquid-detecting 460 preferably form as one mutually by sintering.By forming liquid-detecting 460 like this, can make the utilization of liquid-detecting 460 become easy.

The material of piezoelectric layer 447 preferably uses lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT) or does not use plumbous leadless piezoelectric film.The material of substrate 441 preferably uses zirconia or aluminium oxide.In addition, oscillating plate 442 preferably uses and substrate 441 identical materials.Upper electrode 449, lower electrode 446, upper electrode terminal 445 and lower electrode terminal 444 can use the material with electric conductivity, for example use metals such as gold, silver, copper, platinum, aluminium, nickel.

About the main part 447a of piezoelectric layer 447, the main part 449a of upper electrode 449 and the main part 446a of lower electrode 446, their center is consistent with the center in chamber 443.In addition, but determine oscillating plate 442 oscillating component circle chamber 443 be centered close to whole liquid pick-up unit 460 in the heart.

But constituted the oscillating component 461 of liquid-detecting 460 with the corresponding part in chamber 443 by the main part 447a of part corresponding among the main part 446a of the oscillating component of the oscillating plate 442 of chamber 443 regulation, lower electrode 446 and the extension 446b, piezoelectric layer 447 and extension 447b and main part 449a corresponding part in chamber 443 and upper electrode 449 and extension 449b with chamber 443.In addition, the center of the oscillating component 461 of this liquid-detecting 460 is consistent with the center of liquid-detecting 460.

In addition, but the oscillating component of the main part 446a of the main part 449a of the main part 447a of piezoelectric layer 447, upper electrode 449, lower electrode 446 and oscillating plate 442 (promptly corresponding with the bottom surface portions 443a in chamber 443 part) has circular shape, thereby the oscillating component 461 of liquid-detecting 460 is shapes symmetrical substantially with respect to the center of liquid-detecting 460.

So, in the present embodiment, because it is big to form than the main part 447a of piezoelectric layer 447 diameter of the main part 446a of lower electrode 446, and on a very big scope, cover the zone corresponding with chamber 443 with the main part 446a of lower electrode 446, so reduced not by the area of the part of the thin thickness that main part 446a covered of lower electrode 446.Therefore, can be suppressed in the middle of the free vibration of the oscillating component behind the imposed deformation, excite except that as the unnecessary high order vibration mode the necessary vibration frequency of detected object.In addition, the part distortion of having only thin thickness when free vibration is very big and deflection piezoelectric layer 447 is very little, thereby the phenomenon that the output that has prevented back electromotive force diminishes, thus compared with the past, the difference between the deformation pattern when deformation pattern when having reduced forced vibration and free vibration.

So,, suppressed generation owing to the unnecessary vibration that produces of asymmetry of structure according to present embodiment, and when having prevented owing to forced vibration and the output reduction of the back electromotive force that the difference of the deformation pattern between the two causes during free vibration.Thus, the accuracy of detection of the resonant frequency of the residual vibration in the oscillating component 461 of liquid-detecting 460 is improved, and the detection of the residual vibration of oscillating component 461 also becomes easy.

In addition, since with on the main part 446a of lower electrode 446 the diameter of main part 447a of stacked piezoelectric layer 447 form forr a short time than the main part 446a of lower electrode 446, and with on the main part 447a of piezoelectric layer 447 the diameter of main part 449a of stacked upper electrode 449 form forr a short time than the main part 447a of piezoelectric layer 447, so the diameter of the part (for example main part 447a of lower electrode 447) that the back forms in manufacture process is littler than the diameter of the part (for example main part 446a of lower electrode 446) that forms earlier.Therefore, while form next part owing to the last can confirm the position of the part that forms earlier, so can carry out the location when stacked accurately.

In addition, because it is little to form than the main part 447a of piezoelectric layer 447 diameter of the main part 446a of lower electrode 446, so can make the edge of bottom surface portions 443a in the edge of main part 446a of lower electrode 446 and chamber 443 adjacent, thus, can reduce not by the area of the part of the thin thickness that main part 446a covered of lower electrode 446.

In addition, because the scope that the oscillating component 461 of liquid-detecting 460 contacts with liquid is only limited to chamber 443 existing scopes,, thus, can detect the ink level in the print cartridge 7 accurately so can accurately carry out the detection of liquid.

Figure 18, Figure 19 A and Figure 19 B are the synoptic diagram of the liquid-detecting 560 of present embodiment, this liquid-detecting 560 has stacked oscillating plate 542 on substrate 541 and the base portion 540 of formation, and this base portion 540 has first 540a respect to one another and second 540b.Be formed with circular chamber (recess) 543 in base portion 540, be used to admit the medium as detected object, this chamber 543 is at first 540a one side opening, and the bottom surface sections 543a in chamber 543 is formed can be by oscillating plate 542 vibrations.In other words, the part of actual vibration has been stipulated its profile by chamber 543 in the whole oscillating plate 542.Two ends in second 540b one side of base portion 540 are formed with lower electrode terminal 544 and upper electrode terminal 545.

On second 540b of base portion 540, be formed with lower electrode (first electrode) 546, this lower electrode 546 has circular main part 546a and extension 546b, and this extension 546b is connected to the direction extension of bottom electrode terminal 544 and with lower electrode terminal 544 from this main part 546a.The center of the circular body part 546a of lower electrode 546 is consistent with the center in chamber 543.

It is big that the diameter of the circular body part 546a of lower electrode 546 is formed than circular cavity 543, thereby be covered with whole and 543 corresponding regions, chamber.

Stacked piezoelectric layer 547 on the lower electrode 546, this piezoelectric layer 547 has circular main part 547a and extension 547b, the diameter of wherein said main part 547a forms greatlyyer than the diameter in chamber 543, thereby cover whole and 543 corresponding regions, chamber, described extension 547b extends out from described main part 547a.

Be laminated with the main part 549a of the annular of upper electrode (second electrode) 549 on piezoelectric layer 547, it is littler than the diameter in chamber 543 that the main part 549a of this upper electrode 549 is formed race diameter, thereby be configured in the inside with 543 corresponding regions, chamber.In addition, upper electrode 549 has extension 549b, and this extension 549b extends out from main part 549a, and the main part 547a of extend past piezoelectric layer 547 and extension 547b top.This extension 549b extends across the extension 547b of piezoelectric layer 547, and is connected with upper electrode terminal 545.

So, the main part 547a of piezoelectric layer 547 becomes the structure that is clipped in the middle by the main part 546a of the main part 549a of upper electrode 549 and lower electrode 546.Thus, can be out of shape driving piezoelectric layer 547 effectively.

What as mentioned above, the diameter of the main part 549a of upper electrode 549 was formed than the main part 547a of piezoelectric layer 547 is little.On the other hand, the main part 546a of lower electrode 546 is covered with whole of main part 547a of piezoelectric layer 547.Therefore, the main part 549a of upper electrode 549 has determined to produce in the whole piezoelectric layer 547 scope of the part of piezoelectric effect.

In addition, the parts that are contained in the liquid-detecting 560 preferably form as one mutually by sintering.By forming liquid-detecting 560 like this, can make the utilization of liquid-detecting 560 become easy.

The material of piezoelectric layer 547 preferably uses lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT) or does not use plumbous leadless piezoelectric film.The material of substrate 541 preferably uses zirconia or aluminium oxide.In addition, oscillating plate 542 preferably uses and substrate ' 541 identical materials.Upper electrode 549, lower electrode 546, upper electrode terminal 545 and lower electrode terminal 544 can use the material with electric conductivity, for example use metals such as gold, silver, copper, platinum, aluminium, nickel.

About the main part 547a of piezoelectric layer 547, the main part 549a of upper electrode 549 and the main part 546a of lower electrode 546, their center is consistent with the center in chamber 543.In addition, but determine oscillating plate 542 oscillating component circle chamber 543 be centered close to whole liquid pick-up unit 560 in the heart.

But constituted the oscillating component 561 of liquid-detecting 560 with the corresponding part in chamber 543 by the main part 547a of part corresponding among the main part 546a of the oscillating component of the oscillating plate 542 of chamber 543 regulation, lower electrode 546, piezoelectric layer 547 and main part 549a corresponding part in chamber 543 and upper electrode 549 and extension 549b with chamber 543.In addition, the center of the oscillating component 561 of this liquid-detecting 560 is consistent with the center of liquid-detecting 560.

In addition, but the oscillating component of the main part 546a of the main part 549a of the main part 547a of piezoelectric layer 547, upper electrode 549, lower electrode 546 and oscillating plate 542 (promptly corresponding with the bottom surface portions 543a in chamber 543 part) has circular shape, thereby the oscillating component 561 of liquid-detecting 560 is shapes symmetrical substantially with respect to the center of liquid-detecting 560.

In addition, the vibration section of liquid-detecting 560 561 is owing to be to apply voltage for piezoelectric layer 547 by upper electrode 549 and lower electrode 546, so to the direction outstanding distortion opposite with chamber 543.

So, in the present embodiment, owing to cover the corresponding zone in whole and chamber 543 with the main part 547a of the main part 546a of lower electrode 546 and piezoelectric layer 547, so compared with the past, the difference between the deformation pattern when deformation pattern when having reduced forced vibration and free vibration.In addition, because the oscillating component 561 of liquid-detecting 560 is shapes symmetrical substantially with respect to the center of liquid-detecting 560, so from this center, the rigidity of described oscillating component 561 is isotropy substantially.

In addition, owing to cover the corresponding zone in whole and chamber 543 with the main part 546a of the diameter lower electrode 546 bigger than chamber 543, so can prevent the unnecessary generation of vibration that the position deviation of lower electrode 546 causes owing to making, thereby can prevent the reduction of accuracy of detection.

In addition, because the main part 549a of upper electrode 549 is formed annular, so as shown in figure 18, the outward flange of the main part 549a of upper electrode 549 can be configured on the position near the edge in chamber 543, thus, part among the extension 549b of upper electrode 549, that be positioned at 543 The corresponding area inside, chamber has diminished, thereby has improved the symmetry of the upper electrode 549 of the part that constitutes oscillating component 561.

Therefore, suppressed generation owing to the unnecessary vibration that produces of asymmetry of structure, and when having prevented owing to forced vibration and the output reduction of the back electromotive force that the difference of the deformation pattern between the two causes during free vibration.Thus, the accuracy of detection of the resonant frequency of the residual vibration in the oscillating component 561 of liquid-detecting 560 is improved, and the detection of the residual vibration of oscillating component 561 also becomes easy.

In addition, because the scope that the oscillating component 561 of liquid-detecting 560 contacts with liquid is only limited to chamber 543 existing scopes,, thus, can detect the ink level in the print cartridge 7 accurately so can accurately carry out the detection of liquid.

Figure 20, Figure 21 A and Figure 21 B are the synoptic diagram of the liquid-detecting 660 of present embodiment, this liquid-detecting 660 has stacked oscillating plate 642 on substrate 641 and the base portion 640 of formation, and this base portion 640 has first 640a respect to one another and second 640b.Be formed with circular chamber (recess) 643 in base portion 640, be used to admit the medium as detected object, this chamber 643 is at first 640a one side opening, and the bottom surface sections 643a in chamber 643 is formed can be by oscillating plate 642 vibrations.In other words, the part of actual vibration has been stipulated its profile by chamber 643 in the whole oscillating plate 642.Two ends in second 640b one side of base portion 640 are formed with lower electrode terminal 644 and upper electrode terminal 645.

On second 640b of base portion 640, be formed with lower electrode (first electrode) 646, this lower electrode 646 has circular main part 646a and extension 646b, and this extension 646b is connected to the direction extension of bottom electrode terminal 644 and with lower electrode terminal 644 from this main part 646a.The center of the circular body part 646a of lower electrode 646 is consistent with the center in chamber 643.

The diameter of the circular body part 646a of lower electrode 646 is formed forr a short time than the diameter of circular cavity 643, and is configured in the inside in the zone corresponding with chamber 643.

Be laminated with the diameter piezoelectric layer 647 bigger, circular than the diameter of the main part 646a of lower electrode 646 on the lower electrode 646, as can be seen from Figure 20, whole piezoelectric layer 647 is configured in the inside in the zone corresponding with chamber 643.In other words, there is not the part of crosscut position corresponding with the edge 643a in chamber 643 and extension in piezoelectric layer 647.

Second 640b one side at base portion 640 is formed with the auxiliary electrode 648 that an end links to each other with upper electrode terminal 645.The position corresponding with the edge 643a in chamber 643 crossed in the outside of this auxiliary electrode 648 643 The corresponding area from the chamber, and extends to the inside in the zone corresponding with chamber 643.Inside in the zone corresponding with chamber 643, the part of auxiliary electrode 648 supports from second 640b one side of substrate 640 part to piezoelectric layer 647.This auxiliary electrode 648 preferably has material identical with lower electrode 646 and identical thickness.So, support from second 640b one side of substrate 640 part to piezoelectric layer 647 by auxiliary electrode 648, it is poor can not to produce ladder on piezoelectric layer 647, thereby can prevent the reduction of physical strength.

It is littler and bigger than the diameter of the main part 646a of lower electrode 646 than the diameter of piezoelectric layer 647 that the main part 649a of the circle of stacked upper electrode (second electrode) 649 on piezoelectric layer 647, this upper electrode 649 are formed diameter.In addition, upper electrode 649 has the extension 649b that extends out and be connected with auxiliary electrode 648 from main part 649a.By Figure 21 B as can be known, the extension 649b of upper electrode 649 and position P that the connection of auxiliary electrode 648 begins are positioned at the scope with corresponding zone, chamber 643.

As shown in Figure 20, upper electrode 649 is electrically connected with upper electrode terminal 645 by auxiliary electrode 648.Via auxiliary electrode 648 upper electrode 649 is connected on the upper electrode terminal 645 like this, it is poor to absorb the ladder that produces from the gross thickness of piezoelectric layer 647 and lower electrode 646 by upper electrode 649 and auxiliary electrode 648 both sides.Therefore, thus can prevent from upper electrode 649 to produce big ladder difference causes physical strength to reduce.

As shown in Figure 20, the main part 649a of upper electrode 649 forms circle, and its center is consistent with the center in chamber 643.It is all littler than the diameter in piezoelectric layer 647 and chamber 643 that the main part 649a of upper electrode 649 is formed diameter.

So, piezoelectric layer 647 becomes the structure that is clipped in the middle by the main part 646a of the main part 649a of upper electrode 649 and lower electrode 646.Thus, can be out of shape driving piezoelectric layer 647 effectively.

In addition, in the main part 649a of the main part 646a of the lower electrode 646 that is electrically connected with piezoelectric layer 647 and upper electrode 649, the diameter of the main part 646a of lower electrode 646 is formed lessly.Therefore, the main part 646a of lower electrode 646 has determined to produce in the piezoelectric layer 647 scope of the part of piezoelectric effect.

In addition, the parts that are contained in the liquid-detecting 660 preferably form as one mutually by sintering.Adorn 660 by forming the liquid detection like this, can make the utilization of liquid-detecting 660 become easy.

The material of piezoelectric layer 647 preferably uses lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT) or does not use plumbous leadless piezoelectric film.The material of substrate 641 preferably uses zirconia or aluminium oxide.In addition, oscillating plate 642 preferably uses and substrate 641 identical materials.Upper electrode 649, lower electrode 646, upper electrode terminal 645 and lower electrode terminal 644 can use the material with electric conductivity, for example use metals such as gold, silver, copper, platinum, aluminium, nickel.

But constituted the oscillating component 661 of liquid-detecting 660 with the corresponding part in chamber 643 by the main part 649a of part, piezoelectric layer 647 and upper electrode 649 corresponding among the main part 646a of the oscillating component of the oscillating plate 642 of chamber 643 regulation, lower electrode 646 and the extension 646b and extension 649b with chamber 643.In addition, the center of the oscillating component 661 of this liquid-detecting 660 is consistent with the center of liquid-detecting 660.

In addition, but the oscillating component of the main part 646a of the main part 649a of piezoelectric layer 647, upper electrode 649, lower electrode 646 and oscillating plate 642 (promptly corresponding with the bottom surface portions 643a in chamber 643 part) has circular shape, and, because whole piezoelectric layer 647 all is configured in the inside in the zone corresponding with chamber 643, so the oscillating component 661 of liquid-detecting 660 is with respect to the center of liquid-detecting 660 shape of symmetry substantially.

So, in the present embodiment, because the oscillating component 661 of liquid-detecting 660 is the centrosymmetric shapes with respect to liquid-detecting 660, so the rigidity of this oscillating component 661 is isotropy from its center.Especially, because the big piezoelectric layer 647 of the rigidity effects of oscillating component 661 is formed circle, so the isotropy of the rigidity of oscillating component 661 significantly improves.Therefore, can suppress generation, thereby improve the accuracy of detection of resonant frequency of residual vibration of the oscillating component 661 of liquid-detecting 660 owing to the unnecessary vibration that produces of asymmetry of structure.

In addition, hard and fragile whole piezoelectric layer 647 is configured in the inside in the zone corresponding with chamber 643, thereby on the position corresponding, does not have piezoelectric layer 647 with the edge 643a in chamber 643.Therefore, the problem that does not have the crackle of the piezoelectric film that on the position corresponding, produces in the past the liquid-detecting with the edge in chamber.

In addition, because the scope that oscillating component 661 contacts with liquid is only limited to chamber 643 existing scopes,, thus, can detect the ink level in the print cartridge 7 accurately so can accurately carry out the detection of liquid.

In addition, variation as above-mentioned embodiment, shown in Figure 22, Figure 23 A and Figure 23 B, except the extension 649b of the extension 646b of the lower electrode 646 that extends in direction opposite towards each other on first straight line at the center by chamber 643 and upper electrode 649, can also on center by chamber 643 and second straight line vertical, a pair of extension 646c that extends from the opposite towards each other direction of the main part 646a of lower electrode 646 be set with described first straight line.

In addition, a pair of extension 646c can be not form continuously from the main part 646a of lower electrode 646 yet, but separates and form from the main part 646a of lower electrode 646.

So, in fact a pair of extension 646c that do not work as electrode is disposed along the straight line at the center by chamber 643, and make its bearing of trend vertical with the extension 649b of the extension 646b of lower electrode 646 and upper electrode 649, thereby compare with the embodiment shown in Figure 20, Figure 21 A and Figure 21 B, the symmetry of oscillating component 661 has improved.That is, in the embodiment shown in Figure 20, Figure 21 A and Figure 21 B oscillating component 661 be shaped as the secondary symmetry, and in the variation shown in Figure 22, Figure 23 A and Figure 23 B, oscillating component 661 be shaped as symmetry four times.So, the symmetry of the shape by improving oscillating component 661 can further reduce unnecessary generation of vibration.

More than be that preferred implementation of the present invention has been carried out being described in detail to a certain degree, but obviously can much change and be out of shape.Therefore, should be understood that, only otherwise depart from the scope of the present invention and spirit, also can implement the present invention in the mode beyond the mode of special narration here.

Claims

1. a liquid-detecting is characterized in that, comprising:

Base portion, it has first and second respect to one another, and is provided with the recess that is used to admit as the medium of detected object, and described recess is formed in described first one side opening, and the bottom surface of described recess is formed and can vibrates;

First electrode, it is formed at described second one side of described base portion, and has a main part, the main part of wherein said first electrode forms with the size bigger than the bottom surface of described recess, thereby cover the almost whole zone corresponding with the bottom surface of described recess, and the main part of described first electrode comprises recessed to the inside from the position corresponding with the edge of the bottom surface of described recess and notch that form;

Piezoelectric layer, it has the main part that forms with than the little size in the bottom surface of described recess, and all be received in the scope in the zone corresponding with the bottom surface of described recess, wherein, the described main part of described piezoelectric layer is except the part corresponding with the described notch of described first electrode, and it roughly all is layered on described first electrode;

Auxiliary electrode, it is formed at described second one side of described base portion, and extend to inside with corresponding zone, the bottom surface of described recess from the outside in the zone corresponding with the bottom surface of described recess, and its part is positioned at the inside of the described notch of described first electrode, and supports a part of described piezoelectric layer from described second one side; With

Second electrode, it has main part and extension, the main part of wherein said second electrode is layered on the described piezoelectric layer, the extension of described second electrode extends out from the main part of described second electrode, and is connected with described auxiliary electrode in the inside in the zone corresponding with the bottom surface of described recess.

2. liquid-detecting as claimed in claim 1, wherein, described piezoelectric layer has outshot, and described outshot described main part from described piezoelectric layer in the scope in the zone corresponding with the bottom surface of described recess is outstanding, and described outshot is supported by described auxiliary electrode.

3. liquid-detecting as claimed in claim 1 or 2, wherein, the described main part of described second electrode forms with the size littler than the described main part of described piezoelectric layer.

4. liquid-detecting as claimed in claim 1, wherein, the described main part of described piezoelectric layer and the described main part of described second electrode are the roughly shape of symmetry with at least one shared axis of symmetry.

5. liquid-detecting as claimed in claim 4, wherein, the described main part of described piezoelectric layer and the described main part of described second electrode all are circular, and are disposed with one heart mutually.

6. a liquid-detecting is characterized in that, comprising:

First electrode, it is formed on described second one side of described base portion with the size bigger than the bottom surface of described recess, thereby covers the whole zone corresponding with the bottom surface of described recess;

Piezoelectric layer, it has main part, the main part of described piezoelectric layer forms with the size littler than the bottom surface of described recess, and in the inner laminated in the zone corresponding with the bottom surface of described recess on described first electrode; With

Second electrode, it has the main part on the described main part that is layered in described piezoelectric layer.

7. liquid-detecting as claimed in claim 6, wherein, described piezoelectric layer also has the extension, the extension of described piezoelectric layer extends out from the described main part of described piezoelectric layer, and crosses the position corresponding with the edge of described recess and extend to outside with corresponding zone, the bottom surface of described recess.

8. as claim 6 or 7 described liquid-detectings, wherein, the described main part of described second electrode forms with the size littler than the described main part of described piezoelectric layer.

9. liquid-detecting as claimed in claim 7, wherein, described second electrode also has the extension, the extension of described second electrode extends out from the described main part of described second electrode, the top, described extension of the described piezoelectric layer of extend past, and extend to the outside in the zone corresponding with the bottom surface of described recess.

10. liquid-detecting as claimed in claim 6, wherein, the described main part of described piezoelectric layer and the described main part of described second electrode are the roughly shape of symmetry with at least one shared axis of symmetry.

11. liquid-detecting as claimed in claim 10, wherein, the described main part of described recess, described piezoelectric layer and the described main part of described second electrode all are circular, and are disposed with one heart mutually.

12. liquid-detecting as claimed in claim 9 wherein, also has between the described extension of described second electrode and the insulation course between the described piezoelectric layer.

13. a liquid-detecting is characterized in that, comprising:

Piezoelectric layer, it has main part, and the main part of described piezoelectric layer forms with the size bigger than the bottom surface of described recess, and covers the whole zone corresponding with the bottom surface of described recess and be layered on described first electrode; With

Second electrode, it has main part, and the main part of described second electrode forms with the size littler than the bottom surface of described recess, and on the described main part of inner laminated at described piezoelectric layer in the zone corresponding with the bottom surface of described recess.

14. liquid-detecting as claimed in claim 13, wherein, the described main part of described piezoelectric layer forms with the size littler than the described main part of described first electrode.

15. as claim 13 or 14 described liquid-detectings, wherein,

Described piezoelectric layer also has the extended extension of described main part from described piezoelectric layer;

Described second electrode also has the extension, and the extension of described second electrode extends out from the described main part of described second electrode, and the top, described extension of the described main part of the described piezoelectric layer of extend past and described piezoelectric layer.

16. liquid-detecting as claimed in claim 13, wherein, the described main part of described piezoelectric layer and the described main part of described second electrode are the roughly shape of symmetry with at least one shared axis of symmetry.

17. liquid-detecting as claimed in claim 16, wherein, the described main part of described recess and described second electrode all is circular, and is disposed with one heart mutually.

18. liquid-detecting as claimed in claim 15 wherein, also has between the described extension of described second electrode and the insulation course between the described piezoelectric layer.

19. a liquid-detecting is characterized in that, comprising:

First electrode, it has main part, and described main part is formed on described second one side of described base portion with the size littler than the bottom surface of described recess, and is configured in the inside in the zone corresponding with the bottom surface of described recess;

Piezoelectric layer, it has main part, and the main part of described piezoelectric layer forms with the size littler than the described main part of described first electrode, and is layered on the described main part of described first electrode; With

Second electrode, it has main part, and the main part of described second electrode forms with the size littler than the described main part of described piezoelectric layer, and is layered on the described main part of described piezoelectric layer.

20. liquid-detecting as claimed in claim 19, wherein,

Described first electrode also has the extension, and the extension of described first electrode extends out from the described main part of described first electrode, and extends to the outside in the zone corresponding with the bottom surface of described recess;

Described piezoelectric layer also has the extension, and the extension of described piezoelectric layer extends out from the described main part of described piezoelectric layer, and extends to the outside in the zone corresponding with the bottom surface of described recess;

Described second electrode also has the extension, and the extension of described second electrode extends out from the described main part of described second electrode, and the top, extension of the described main part of the described piezoelectric layer of extend past and described piezoelectric layer.

21. as claim 19 or 20 described liquid-detectings, wherein, the described main part of described recess and described first electrode all is circular, and is disposed with one heart mutually; The size of the diameter of the described main part of described first electrode is more than 75% of diameter of described recess.

22. a liquid-detecting is characterized in that, comprising:

Second electrode, it has the main part of annular, the main part of described second electrode forms with the race diameter size littler than the bottom surface of described recess, and on the described main part of inner laminated at described piezoelectric layer in the zone corresponding with the bottom surface of described recess.

23. liquid-detecting as claimed in claim 22, wherein, the described main part of described piezoelectric layer forms with the size littler than the described main part of described first electrode.

24. as claim 22 or 23 described liquid-detectings, wherein,

25. liquid-detecting as claimed in claim 22, wherein, the described main part of described piezoelectric layer and the described main part of described second electrode are the roughly shape of symmetry with at least one shared axis of symmetry.

26. liquid-detecting as claimed in claim 25, wherein, described recess is circular; The described main part of described second electrode is an annular; The described main part of described recess and described second electrode is disposed mutually with one heart.

27. a liquid-detecting is characterized in that, comprising:

First electrode, it is formed at described second one side of described base portion, and have main part and an extension, the main part of wherein said first electrode forms with the size littler than the bottom surface of described recess, and be configured in the inside in the zone corresponding with the bottom surface of described recess, the extension of described first electrode extends out from the main part of described first electrode, and extends to the outside in the zone corresponding with the bottom surface of described recess;

Piezoelectric layer, it forms with the size littler than the bottom surface of described recess, and is layered on described first electrode, and it all is configured in the inside in the zone corresponding with the bottom surface of described recess;

Auxiliary electrode, it is formed at described second one side of described base portion, and extend to inside with corresponding zone, the bottom surface of described recess from the outside in the zone corresponding with the bottom surface of described recess, and its part supports a part of described piezoelectric layer from described second one side; With

Second electrode, it has main part and extension, the main part of wherein said second electrode is layered on the described piezoelectric layer, and the extension of described second electrode extends out and is connected with described auxiliary electrode in the inside in the zone corresponding with the bottom surface of described recess from the main part of described second electrode.

28. liquid-detecting as claimed in claim 27, wherein, the size of the described main part of described first electrode is littler than the size of described piezoelectric layer; The size of the described main part of described second electrode is bigger than the size of the described main part of described first electrode.

29. as claim 27 or 28 described liquid-detectings, wherein, the size of the described main part of described second electrode is littler than the size of described piezoelectric layer.

30. as liquid-detecting as described in the claim 27, wherein,

The described extension of described first electrode and the described extension of described second electrode opposite towards each other direction on first straight line at the center by described recess is extended;

Described first electrode also has a pair of extension, described a pair of extension the center by described recess and with vertical second straight line of described first straight line on extend from the opposite towards each other direction of the described main part of described first electrode.

31. liquid-detecting as claimed in claim 30, wherein, separate with the described main part of described first electrode described a pair of extension.

32. as liquid-detecting as described in the claim 27, wherein, the described main part of the described main part of described first electrode, described piezoelectric layer and the described main part of described second electrode all are circular, and are disposed with one heart mutually.

33. a liquid container is characterized in that, comprising:

The container body that is used for storaging liquid; With

Each described liquid-detecting in the claim 1 to 32,

Wherein, the described recess of described liquid-detecting is exposed in the fluid storage space of described container body.

34. liquid container as claimed in claim 33 wherein, stores the liquid that liquid injection apparatus is used in the described container body.

35. liquid container as claimed in claim 34, wherein, described liquid injection apparatus is an inkjet recording device; Store ink in the described container body.