JPH05332860A - Pressure sensitive sensor and recorder using pressure sensitive sensor - Google Patents

Abstract

PURPOSE:To remove instability of pressure to be detected caused by a contact point by detecting the changing amount of a flexible member caused by the pressure of fluid without contact. CONSTITUTION:An adjusting tube 102 is embedded in a main body 101 so as to obtain balance with a flexible member 104 at an intended initially set pressure. The member 104 is elastically deformed by the intended value and fixed with an adjusting-tube holding part 110. A detecting member 106 is held with a detecting-member holding part 107 so that the interval between a member to be detected 105 and the detecting member 106 becomes the constant distance under the no-pressure state on the member 104. A pressure sensitive chamber 103 is filled with fluid from a fluid storing tank by way of an inlet port 109. The fluid is made to flow out through an outlet port 109A. When the fluid in the tank becomes less and the outflow continues, the pressure in the pressure sensitive chamber 103 becomes negative. The member 104 is deformed, and the detecting distance is changed. The change is detected with the member 106. The signal is transmitted to the outside through output terminals 108 and 108A. As a detecting method, an eddy-current measuring device is used. However, a magnet and a lead switch can be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive sensor which operates by changing the pressure of a fluid such as liquid or gas.

In particular, the present invention relates to a pressure-sensitive sensor which operates by a slight differential pressure of fluid.

[0003]

2. Description of the Related Art Many conventional pressure-sensitive sensors have a structure as shown in FIG. In these conventional sensors, an elastic body 22 is provided on a part of the wall surface of the pressure sensing chamber, and the force exerted by the elastic body upward and the force for lowering the member 28 by the elastic body 25 are equalized. Is made like.
A metal ring 23 for contact is attached to the lower elastic body 22, and the contact electrode 2 attached to the upper body 24
6, contact is made. The contact between these contacts is interrupted by the movement of the elastic body 22 due to the pressure change in the pressure sensitive chamber 21, and the detection signal is transmitted by the signal connecting line 27 to operate as a sensor.

In such a conventional pressure-sensitive sensor, the detected pressure is determined by the pressure change between the pressure change in the pressure-sensitive chamber 21 and the pressure balance between the elastic body 25 and the detecting elastic body 22 for adjusting the set value of the pressure. Is done.

[0005]

However, in the above-mentioned conventional method, an elastic body capable of operating with a slight pressure is required, and a certain contact pressure is required to ensure contact at the contact portion. In addition, this force corresponding to the contact pressure is applied to the elastic body that needs to be operated with a slight pressure. For this reason, the amount of elastic deformation increases, and the relationship between the pressure during operation and the amount of deformation of the elastic body is no longer linear.Since it is detected by turning the contact on and off, the contact positional relationship, surface condition, and contact resistance It was difficult to sense the slight differential pressure because it was affected by the partial difference.

Further, there is a concern that foreign matter such as dust and dust may enter the contact portion, and dirt, corrosion, rust, etc. may occur during assembly, so that it is difficult to guarantee the accuracy of the detected pressure.

[0007]

A typical means of the present invention for solving the above-mentioned problems has a flexible member which is displaced by the pressure of a fluid, and the flexible member is arranged in the displacement direction of the flexible member. This is to use a pressure-sensitive sensor characterized by performing pressure detection by detecting a displacement amount in a non-contact manner.

[0008]

In the above means, the distance between the detection member and the detection member attached to the flexible member for detecting the displacement amount of the flexible member due to the pressure of the fluid does not depend on whether the contact is on or off. Is measured without contact. Therefore, it is possible to easily detect a slight pressure without requiring the initial pressure that is applied to ensure contact between the contacts in the conventional pressure-sensitive sensor. Further, since the means does not have an electrical contact, the influence of the surface condition of the contact and the non-uniformity of the contact resistance, and the instability of the detection pressure due to foreign matter such as dust and dust adhering to the contact part You can eliminate the problem.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the pressure sensitive sensor to which the above means is applied will be described below with reference to the drawings.

FIG. 1 shows a schematic sectional view of an embodiment of the present invention. Reference numeral 101 in the figure is a pressure-sensitive sensor main body.
The adjusting cylinder 102, which also serves to adjust the operating pressure and hold the detection member 106, is attached to the holding portion 110.

The detection member 106 is held by the detection member holding portion 107. Reference numerals 109 and 109 </ b> A are a fluid inlet to the pressure sensitive chamber 103 and a fluid outlet from the pressure sensitive chamber 103. A pressure-sensitive flexible member 104 that is displaced by the pressure in the pressure-sensitive chamber 103 is provided on a part of the wall surface of the pressure-sensitive chamber 103. The flexible material is butyl rubber, EPDM, or the like.
It is preferable to use CR rubber or the like. Flexible member 10
A member 105 to be detected, such as a metal or a magnetic material, was embedded in the inside of substantially the center of 4 by insert molding or the like.
108 and 108A are output terminals for taking out signals to the outside.

In this structure, first, the adjusting cylinder 102 is assembled in the main body so that the pressure-sensitive sensor operates according to a desired detection pressure. The adjustment tube 102 is attached to the main body 101 so as to be balanced with the flexible member 104 at a desired initial setting pressure.
When the flexible member 104 is elastically changed by a desired amount due to contact with the adjustment cylinder 102,
It was fixed by the adjusting tube holding unit 110.

The position of the detection member 106 is determined so that the distance between the detection member 105 and the detection member 106 is always a constant distance L in the initial state where no pressure is applied to the flexible member. The holding member 107 detects the detection member 10
6 was retained.

From the fluid storage tank (not shown) to the inlet 10
The pressure-sensitive chamber 103 is filled with fluid through 9. At this time, by selecting a water-repellent material for the lower part 111 of the main body or the flexible member, or by setting the attachment position of the outlet 109A to a position where bubbles easily escape, the pressure-sensitive chamber can be used even when liquid is used. It is possible to prevent the inclusion of air bubbles.

The fluid continues to flow from the outlet 109A, and the amount of the fluid in the fluid storage tank (not shown) is reduced, so that the inlet 1
When the supply of fluid from 09 becomes small, the pressure in the pressure sensing chamber becomes negative, and when the desired detection pressure set above is exceeded,
The flexible member 104 deforms and the detection distance L changes. The change in the detection distance L is detected by the detection member 106, and a signal is transmitted from the output terminals 108 and 108A to the outside. An eddy current measuring device capable of measuring a minute change was used as the detection member 106, but a member that emits magnetic force such as a magnet is used as the detection target member and is generally used as a detection member in a reed switch. A member that operates by a magnetic force as described above may be used.

Further, as shown in this embodiment, the detection direction of the detection member is set to be the same as the displacement direction of the member to be detected, and the displacement of each distance is detected to continuously detect the remaining amount of ink. It is also possible to do so.

(Other Embodiments) In the above embodiments, a method of embedding a metal to be detected in a flexible member by a method such as insert molding is used.
A flexible member 10 having a metal film directly formed by metal sputtering or the like.
It may be provided on the detection surface side of No. 4. By doing so,
In addition to being able to obtain a more elastic detecting portion, manufacturing errors that occur during embedding can be ignored.
Further, in this case, since it is not necessary to embed the member to be detected, it is possible to reduce the thickness of the flexible member, which makes it possible to detect even a minute pressure and also reduce the thickness of the entire device. Is possible. Further, when the metal by the sputtering method is also provided on the surface on the pressure sensitive chamber side, it serves as a protective film against gas and liquid that violate the flexible member, so that deterioration of the flexible member can be suppressed. In addition, since a flexible member such as SBR can be plated with metal, it is an effective method for further reducing the cost. As described above, when the metal film is provided as the member to be detected on the surface of the flexible member, in addition to the detection method using the detecting member shown in the previous embodiment, an optical system including a light emitting element and a light receiving element is used. May be used. This is a method in which light is applied to the metallic glossy surface or the mirror surface portion of the test value member created by plating, sputtering, or the like, and the change in the reflected light is detected and detection is performed.

(Other Embodiments) FIG. 3 shows an embodiment of the present invention in which the pressure-sensitive sensor of the present invention is mounted in an ink supply path as an ink pressure detecting means of an ink jet recording apparatus. Here, 301 is a recording head, and the sub tank 30
By ejecting the ink supplied from No. 2 from the ejection port of the head, recording is performed on the recording medium which is the recording medium. The recording medium is a feeding roller 308 and a pinch roller 309.
Transported by A and 309B. A sensor 310 as an ink pressure detection unit is arranged in a supply path of ink supplied from the ink tank 305 in the ink cartridge 304 to the sub tank 302. The sensor 310 may be close to the sub tank or close to the ink tank on the ink supply path, and may be determined depending on the positional relationship (height or the like) between the head 301 and the ink cartridge.
It goes without saying that the sensor may be arranged on the carriage or near the recording head.

The present invention brings excellent effects particularly in a recording head and a recording apparatus for ink jet recording in which flying droplets are formed by utilizing thermal energy in an ink jet recording system.

With regard to its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred. This method is a so-called on-demand type,
Although applicable to any of the continuous type, particularly in the case of the on-demand type, an electrothermal converter arranged corresponding to a sheet or a liquid path holding a recording liquid (ink). In addition, by applying at least one driving signal corresponding to the recording information and giving a rapid temperature rise exceeding nucleate boiling to the recording liquid, heat energy is generated in the electrothermal converter, and the thermal action of the recording head is generated. This is effective because the recording liquid in the vicinity of the surface is film-boiled, and as a result, bubbles can be formed in the recording liquid in a one-to-one correspondence with this drive signal.
The recording liquid is ejected into the atmosphere through the ejection port by the action force generated in the process of growth and contraction of the bubbles to form at least one droplet. It is more preferable to make this drive signal in a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that the ejection of the recording liquid with excellent responsiveness can be achieved. As this pulse-shaped drive signal, US Pat.
Those described in US Pat. Nos. 4,633,359 and 4,345,262 are suitable. Incidentally, US Pat. No. 43131 of the invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in the specification of No. 24 are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, U.S. Pat. No. 4,558,333, U.S. Pat. No. 44, which discloses a configuration in which a heat acting portion is arranged in a bending region.
The configuration using the specification of No. 59600 is also included in the present invention. Further, as a full line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length can be changed by combining a plurality of recording heads as disclosed in the above specification. It may be either a satisfying constitution or a constitution as one recording head integrally formed, but in any case, the present invention is
The effects described above can be more effectively exhibited.

In addition, the ink is attached to the replaceable chip type recording head, or the recording head itself, which can be electrically connected to the apparatus main body and can supply ink from the apparatus main body by being mounted on the apparatus main body. The present invention is also effective when a cartridge-type recording head integrally provided with a supply tank is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc., which are also provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized. .. If these are specifically mentioned,
Capping means for the recording head, cleaning means, pressurizing or suctioning means, electrothermal converter or other heating element or preheating means by a combination thereof,
Performing a preliminary ejection mode for performing preliminary ejection different from recording is also effective for stable recording.

Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrally formed or a plurality of combinations may be used. The present invention is also extremely effective for a device provided with at least one of full color by color mixing.

In addition, as a form of the recording apparatus provided with the recording mechanism using the liquid jet recording head of the present invention, in addition to the one used as an image output terminal of information processing equipment such as a computer, it is combined with a reader or the like. It may be in the form of a copying machine or a facsimile machine having a transmission / reception function.

FIG. 4 is a block diagram showing a schematic configuration when the recording apparatus of the present invention is applied to an information processing apparatus having a function as a word processor, a personal computer, a facsimile apparatus, and a copying apparatus.

In the figure, reference numeral 401 denotes a control unit for controlling the entire apparatus, which includes a CPU such as a microprocessor and various I / O ports, outputs control signals and data signals to each unit, and controls signals from each unit. And data signals are input to control. A display unit 402 has various menus, document information, and an image reader 407 on the display screen.
The image data and the like read by is displayed. Reference numeral 403 denotes a transparent pressure-sensitive touch panel provided on the display unit 402. By pressing the surface of the touch panel with a finger or the like, it is possible to perform item input or coordinate position input on the display unit 402.

404 is an FM (Frequency Mo)
In the sound source unit, music information created by a music editor or the like is stored as digital data in the memory unit 410 or the external storage device 412, and is read from the memory or the like to perform FM modulation. FM sound source section 4
The electric signal from 04 is converted into an audible sound by the speaker unit 405. The printer unit 406 has the storage device of the present invention applied as an output terminal of a word processor, a personal computer, a facsimile device, and a copying device.

Reference numeral 407 denotes an image reader unit for photoelectrically reading and inputting original data, which is provided in the middle of the original conveying path and reads various originals such as facsimile originals and copy originals. Reference numeral 408 denotes a transmission / reception unit for transmitting a facsimile of original data read by the image reader unit or 407 and a facsimile (FAX) for receiving and decoding the transmitted facsimile signal and having an interface function with the outside. A telephone unit 409 has various telephone functions such as a normal telephone function and an answering machine function.

A memory unit 410 includes a ROM for storing a system program, a manager program, other application programs, etc., a character font, a dictionary, etc., an application program loaded from an external storage device 412, document information, and a video RAM. Is.

Reference numeral 411 is a keyboard unit for inputting document information and various commands.

An external storage device using a floppy disk, a hard disk or the like as a storage medium.
2 stores document information, music or voice information, a user application program, and the like.

FIG. 5 is a schematic external view of the information processing apparatus shown in FIG.

In the figure, 501 is a flat panel display using liquid crystal or the like, which displays various menus, graphic information, document information and the like. A touch panel 403 is installed on the display 501, and by pressing the surface of the touch panel 403 with a finger or the like, coordinate input and item designation input can be performed. 502 is a handset used when the device functions as a telephone. The keyboard 503 is detachably connected to the main body via a cord, and various document information and various data can be input. The keyboard 503 is provided with various function keys 504 and the like. Reference numeral 505 is an insertion port of a floppy disk into the external storage device 212.

Reference numeral 506 denotes a paper placing portion on which an original read by the image reader 407 is placed, and the read original is ejected from the rear of the apparatus. When receiving a facsimile, the data is recorded by the inkjet printer 507.

In the above, the display unit 402 is a CRT.
However, a flat panel such as a liquid crystal display using a ferroelectric liquid crystal is preferable. This is because in addition to being small and thin, it is possible to reduce the weight.

When the information processing apparatus functions as a personal computer or a word processor, various information input from the keyboard unit 211 is processed by the control unit 401 according to a predetermined program, and the printer unit 406.
Is output as an image.

When functioning as a receiver of a facsimile apparatus, the facsimile information input from the FAX transmission / reception unit 408 via the communication line is received by the control unit 401 according to a predetermined program, and output as a received image to the printer unit 406. ..

Further, in the case of functioning as a copying apparatus, an original is read by the image reader unit 407, and the read original data is output as a copied image to the printer unit 406 via the control unit 401. In the case of functioning as a transmitter of a facsimile machine, the document data read by the image reader unit 407 is transmitted by the control unit 401 according to a predetermined program, and then the FAX transmission / reception unit 4 is operated.
08 to the communication line.

The information processing apparatus described above may be an integrated type in which an ink jet printer is built in the main body as shown in FIG. 6, and in this case, it becomes possible to further enhance the portability. In the figure, the parts having the same functions as those in FIG.

By applying the recording apparatus of the present invention to the multifunctional information processing apparatus described above, a high-quality recorded image can be obtained at high speed and with low noise, so that the function of the information processing apparatus is further improved. It becomes possible.

[0042]

According to the present invention, when the displacement of the pressure of the liquid is sensed in the contact solution as the displacement of the flexible member accompanying the change of the pressure, the detected pressure is very small or the detection accuracy is required. Can also sense.

Further, since the displacement of the above-mentioned pressure is sensed by the distance between the flexible member and the detecting means, it is possible to sense the pressure of the liquid successively.

Further, in a recording apparatus equipped with this sensor, it is possible to sense a minute change in the ink amount and pressure, and more stable recording can be performed.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a pressure-sensitive switch of the present invention.

FIG. 2 is a schematic view showing a cross section of a conventional pressure sensitive switch.

FIG. 3 is a diagram showing an ink supply system of a recording apparatus using the pressure sensitive switch of the present invention.

FIG. 4 is a block diagram showing a schematic configuration when the recording apparatus of the present invention is applied to an information processing apparatus.

5 shows a schematic external view of the information processing apparatus shown in FIG.

FIG. 6 is a schematic diagram showing a row of an information processing apparatus using the present invention.

[Explanation of symbols]

 102 Adjustment Cylinder 103 Pressure Sensitive Chamber 104 Flexible Member 105 Detected Member 106 Detection Member 106 Detection Member Holding Part 108, 108A Output Terminal 109 Inlet 109A Outlet 110 Adjustment Cylinder Holding Part 21 Pressure Sensitive Chamber 22, 25 Elastic Body 23 Metal ring for contact 26 Contact electrode 301 Recording head 302 Sub tank 305 Ink tank 306 Ink supply path 310 Ink pressure detection sensor

Claims (2)

[Claims] 1. A pressure-sensitive sensor that operates by detecting the pressure of a fluid, wherein the pressure-sensitive sensor has a flexible member that is displaced by the pressure of the fluid, and in the displacement direction of the flexible member. A pressure-sensitive sensor characterized in that pressure detection is performed by a detection means that detects a displacement amount in a non-contact manner. 2. The recording apparatus according to claim 1, wherein the recording head has a recording head that ejects ink onto a recording medium to perform recording, and an ink tank and an ink supply path for supplying ink to the recording head. A recording apparatus having a pressure sensor.