JP3043538B2 - Ink head recovery device for inkjet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink head recovery device for an ink jet recording apparatus.

[0002]

2. Description of the Related Art In recent years, OA equipment such as computers, word processors, and copying machines have become widespread, and many recording methods for these recording apparatuses have been developed. The ink jet recording apparatus has excellent features that high definition is easy, high speed, excellent in quietness, and inexpensive as compared with other systems.

However, since the ink jet recording apparatus is a method in which ink droplets are ejected from a recording head to perform recording, the ink in the recording head is thickened by evaporation of water or the like, and paper in the recording head is not printed. When a foreign substance such as powder is mixed, discharge may not be performed even by applying discharge energy.

Conventionally, an ink suction operation for recovering a head from an ink discharge surface of an ink head is performed by pressing a cap against the ink discharge surface, sealing between the head and the cap, and depressurizing the inside of the cap chamber by a suction pump to discharge ink. I was sucking out of the head.

[0005]

However, the above-mentioned prior art has the following disadvantages. (1) Since the ink ejection surface has not a single plane but a step or an inclined surface, an operation of evenly contacting the cap or increasing the pressing force is performed to maintain the airtightness in the cap chamber. Needed. (2) Dust such as fixed ink or paper dust is easily sandwiched between the pressing surfaces, and therefore, leakage from the cap is likely to occur. (3) If the elastic member cap is pressed for a long time, the pressing force is weakened due to a temporal change of the material or the like, and a leak occurs from the cap.

Accordingly, an object of the present invention is to provide a structure in which the contact portion of the cap with the ink ejection surface of the ink head has a balloon structure, provide a suction pump with a positive pressure generating portion, and inflate the balloon at the contact portion of the cap to make uniform contact. By increasing the pressing force, good airtightness at the cap contact part,
Accordingly, it is an object of the present invention to provide an ink head recovery device having good ink suction efficiency.

[0007]

According to the present invention, there is provided an ink head recovery apparatus for an ink jet recording apparatus, comprising: an ink suction pump having a mechanism for generating a positive pressure part and a negative pressure part for ink suction in a cylinder; A cap having a balloon portion formed by an elastic member and being in communication with the positive pressure portion at a peripheral portion thereof, wherein the balane portion is pressed against the ink ejection surface of the ink head when the balane portion is pressed. Have,
It is characterized by:

[0008]

The ink ejection surface of the ink head is pressed against the cap and is isolated from the outside air. When the piston moves to the left, the pump chamber A becomes negative pressure due to the operation of each valve membrane, valve hole, etc.
The pump chamber B has a positive pressure. At that time, the inside of the balloon portion 4a communicating with the pump chamber B is pressurized and inflated. Therefore, even when the ejection surface is not a uniform flat surface, the contact portion is further pressed and evenly adhered, following the complicated shape of the ink ejection surface. You. Since the airtightness between the ink ejection surface and the outside air is maintained in this manner, the ink suction operation can be performed efficiently.

[0009]

FIG. 1 is a schematic plan view showing a state in which ink is being sucked from an ink head in an ink head recovery apparatus of an ink jet recording apparatus according to an embodiment of the present invention. FIG. FIG. 3 is an enlarged perspective view of a partly broken view from the perspective.
1 is an external view of an ink head using the present embodiment.

As shown in FIGS. 1 and 2, the ink head recovery device 10 mainly includes an ink suction pump 1 and a cap 4, and the main part of the pump 1 includes a cylinder 5 and a piston 7. The cylinder 5 faces the ink head 11 in a direction perpendicular to the direction of movement M of the piston 7, and has an orifice portion 5a at a substantially central portion of a side surface facing the ink head 11, and a communication port 5b at a left end portion. ing. The cap 4 is connected to the orifice portion 5a and the communication port 5b.
The orifice 5a is always connected to the cap chamber 4b of the cap, and the communication port 5b is connected to the balloon 4a.

The cylinder 5 is provided with a valve hole 5c for discharging ink at the center of the right end and a valve membrane 2 outside thereof, and the piston 7 is provided with a valve hole 7a penetrating in the traveling direction and the valve membrane 3 outside the left end thereof. ing. O-rings 6 and 8 are provided to keep the piston and cylinder airtight. With these mechanisms, the cylinder 5 simultaneously generates negative pressure and positive pressure in the pump chambers A and B by moving the piston 7 to the left in FIG. 1, respectively. 4b, the structure exerting on the balloon portion 4a.

The balloon portion 4a of the cap 4, which is the most characteristic of this embodiment, is made of a substantially annular double-structured elastic member, and is located on the opposite side of the flange to be fitted with the orifice portion 5a. It is pressed against the tip end surface of the head 11 to maintain the airtightness between the ink ejection surface 11a and the outside air.

Next, the operation of this embodiment will be described.

The ink ejection surface 11a of the ink head 11
Is pressed against the cap 4 and is isolated from the outside air.
Ink suction pump 1 consisting of cylinder 5 and piston 7
When the piston 7 moves to the left, the valve membrane 2 closes the valve hole 5c, the valve membrane 3 closes the valve hole 7a, and the pump chamber A is decompressed and expanded. When the O-ring 8 passes through the orifice portion 5a, the pressure in the cap chamber 4b becomes negative at once, and the clogged ink is sucked. At that time,
Since the pump chamber B is compressed, the inside of the balloon portion 4a is pressurized and expands, and the contact portion is further pressed against the ink discharge surface having a complicated shape to be evenly adhered.
In this manner, the ink ejection surface is kept airtight with the outside due to the close contact, so that the ink suction operation can be performed efficiently. When the piston 7 moves to the right, the valve membranes 2, 3 open and the pump chambers A,
B returns to atmospheric pressure.

The above description has been given of the case where the present embodiment is used in an ink head recovery device of an ink jet recording apparatus. In addition, a cartridge for storing a mo-color ink head in use in a usable state can be used. It can also be used for storage box recovery devices.

The present invention provides an excellent effect in an ink jet type recording head and a recording apparatus in which a flying droplet is formed by utilizing thermal energy among the ink jet recording methods and recording is performed.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method can be applied to both the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, liquid (ink)
By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling to an electrothermal transducer arranged corresponding to the sheet or liquid path in which This is effective because heat energy is generated in the electrothermal transducer, causing film boiling on the heat-acting surface of the recording head, and as a result, air bubbles in the liquid (ink) corresponding one-to-one to this drive signal can be formed. It is. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination configuration (a linear liquid flow path or a right-angle liquid flow path) of a discharge port, a liquid path, and an electrothermal converter as disclosed in the above-mentioned respective specifications, The present invention also includes a configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which a heat acting portion is arranged in a bending region.

In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and absorbs pressure waves of thermal energy. The present invention is also effective as a configuration based on JP-A-59-138461, which discloses a configuration in which an opening corresponds to a discharge unit.

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 is determined by combining a plurality of recording heads as disclosed in the above-mentioned specification. The present invention can exhibit the above-mentioned effects more effectively, though it may be either a configuration that satisfies the above requirements or a configuration as a single recording head that is formed integrally.

In addition, it is integrated with a replaceable chip-type recording head, which is mounted on the apparatus main body to enable electrical connection with the apparatus main body and supply of ink from the apparatus main body, or integrated with the recording head itself. The present invention is also effective when a cartridge type recording head provided with an ink tank is used.

It is preferable to add recovery means for the print head, preliminary auxiliary means, and the like provided as components of the printing apparatus of the present invention since the effects of the present invention can be further stabilized. If you list these specifically,
Capping means, cleaning means, pressurizing or suction means for the printhead, preheating means using an electrothermal transducer or another heating element or a combination thereof, and a preliminary ejection mode for performing ejection other than recording Is also effective for performing stable recording.

The recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black. The recording head may be integrally formed or a plurality of recording heads may be combined. The present invention is also extremely effective for an apparatus provided with at least one of full colors by color mixture.

In the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens at room temperature, or which is liquid, In general, in the ink jet method, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. What is necessary is just to be liquid.

In addition, the temperature rise due to thermal energy can be positively prevented by using it as energy for changing the state of the ink from a solid state to a liquid state, or solidified in a standing state for the purpose of preventing evaporation of the ink. Either ink may be used, or in any case, the ink may be liquefied by application of heat energy according to the recording signal and ejected as a liquid ink, or may already start to solidify when reaching the recording medium. The use of ink having a property of being liquefied for the first time by heat energy is also applicable to the present invention. In such a case, the ink is disclosed in JP-A-54-5684.
No. 7 or Japanese Patent Application Laid-Open No. 60-71260, in which the porous sheet is opposed to the electrothermal converter while being held in a liquid or solid state in the concave portions or through holes of the porous sheet. It may be. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition to the above, the recording apparatus according to the present invention may be provided as an image output terminal of an information processing apparatus such as a word processor or a computer as an integral or separate unit, a copying apparatus combined with a reader, and the like. May take the form of a facsimile machine having a transmission / reception function.

[0028]

As described above, according to the present invention, the contact portion of the cap with the ink discharge surface of the ink head has a balloon structure, so that even if the ink discharge surface is not a precise flat surface, a uniform pressure can be applied to the discharge surface. Can be pressed with
It is possible to provide an ink head recovery device that can maintain airtightness in the cap chamber at the time of sucking ink even if mixed ink or paper dust is mixed, and that does not particularly increase the cost for generating pressure.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a state where ink is being sucked from an ink head of an embodiment of an ink head recovery device of an ink jet recording apparatus according to the present invention.

FIG. 2 is a partially broken enlarged perspective view of the cap of FIG.

FIG. 3 is an external view of an ink head using the present embodiment.

[Description of Signs] 1 Ink suction pump 2, 3 Valve membrane 4 Cap 4a Balloon portion 4b Cap chamber 5 Cylinder 5a Orifice portion 5b Communication port 5c, 7a Valve hole 6, 8 O-ring 7 Piston 9 Waste ink absorber 10 Ink head Recovery device 11 Ink head 11a Ink ejection surface 11b Ink ejection port A Pump chamber (negative pressure generating section) B Pump chamber (positive pressure generating section) M Movement direction

Continuation of the front page (56) References JP-A-60-2368 (JP, A) JP-A-4-78543 (JP, A) JP-A-57-210866 (JP, A) JP-A-4-87248 (JP) (U, U) 58-58,842 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/18 B41J 2/165 B41J 2/185

Claims (3)

(57) [Claims] 1. An ink head recovery device for an ink jet recording apparatus, comprising: an ink suction pump having a mechanism for generating a positive pressure portion at the same time as a negative pressure portion for ink suction in a cylinder; And a cap having a balloon portion formed by an elastic member and having a double portion, wherein the balane portion is pressed against the ink ejection surface of the ink head when the balane portion is pressed. An ink head recovery device for an inkjet recording device. 2. The ink jet recovery apparatus according to claim 1, wherein the ink head includes an electrothermal converter for generating thermal energy for discharging ink. 3. The ink jet recording apparatus according to claim 2, wherein the ink head discharges the ink from a discharge port using film boiling generated in the ink by thermal energy applied by the electrothermal transducer. apparatus.