JPH0437556A - Ink jet recording device - Google Patents

Abstract

PURPOSE:To prevent a medium for recording from becoming contaminated or a discharge orifice of a recording head from becoming blocked by providing an ink absorbing element which absorbs extra ink wiped off by a wiping member, and covering the ink absorbing element using a covering material, in the form of a thin plate having through-holes, fixed to the recording head. CONSTITUTION:One surface of ink absorbing elements 3, 4, each consisting of porous resin is fixed to both lateral surfaces of a recording head 1. Each ink absorbing surface 3a, 4a of the ink absorbing elements 3, 4 is formed, in parallel with a discharge orifice surface 1a, at a position which is adjacent to the both sides of the discharge orifice surface 1a and recedes from the discharge orifice surface 1a to the extent of the thickness of covering members 5, 6. The covering members 5, 6 which cover the entire surface of each ink absorbing surface 3a,4a consists of a material having appropriate rigidity and abrasion resistance, and have many through-holes 5. The extra ink sticking to the discharge orifice surface 1a is wiped off by a wiping member 2, then is carried to the sliding contact surface of the covering members 5, 6 and finally is absorbed by the ink absorbing element 3 after passing through the through- holes 5a, 6a.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application 1] The present invention relates to an inkjet printing apparatus that performs printing by ejecting ink from an ejection port of a printhead, and particularly relates to an inkjet printing apparatus that performs printing by ejecting ink from an ejection port of a printhead. The present invention relates to an inkjet recording apparatus having the following.

[Prior art 1] In a conventional inkjet recording apparatus, as shown in FIGS. 10 and 11, a recording head 71 has an ejection opening surface 71a on which a plurality of ejection lowers 1b for ejecting ink are arranged. It is formed.

During recording, ink ejected toward a recording medium (not shown) that is slightly separated from the recording medium may bounce off the recording medium and adhere to the ejection port surface 71a, or some of the ejected ink may Since the unnecessary ink may adhere as a mist of ink and become dirty, a resilient plate-shaped wiper member 72 is provided as a means for removing unnecessary ink and cleaning the ejection port surface 71a. There is.

The wiper member 72 is curved in contact with the ejection port surface 71a and wipes away unnecessary ink 76 from the ejection port surface 71a by sliding relative to the ejection port surface 71a. If the unnecessary ink 72 leaves the ejection port surface 71a and returns to its original shape while wiping off the unnecessary ink 76, the unnecessary ink 76 will be scattered by the wiper member 72. An ink absorber for absorbing unnecessary ink 76 is provided.

Since the recording head 71 shown in FIGS. 10 and 11 reciprocates in the direction of arrow G and the opposite direction, two ink absorbers 74a and 74c are disposed on both sides of the recording head 71, respectively. There is. The two ink absorbers 74
The ink absorbing surfaces 74b and 74d a and 74c are formed adjacent to both sides of the ejection port surface 71a, and slide relative to the wiper member 72 to remove unnecessary ink 76 wiped by the wiper member 72. It is structured to absorb.

[Problem to be Solved by the Invention 1] In the conventional inkjet recording device described above, as the ink absorber absorbs unnecessary ink, it expands as shown in FIG. There is a problem in that the ink absorbing surface 74°b of a is protruded and comes into contact with the recording medium during recording, thereby staining the recording medium.

Furthermore, since the ink absorbing surface of the ink absorber slides on the wiper member, the ink absorbing surface 74"d may wear out, as shown in FIG.
There is a problem in that the debris of the ink absorber 74c peeled off from the ink absorber 74c may clog the ejection opening of the recording head 71.

The present invention has been made in view of the above-mentioned problems of the conventional technology, and the ink absorbing surface of the ink absorber comes into contact with the recording medium due to expansion of the ink absorber and stains the recording medium. To provide an inkjet recording device in which the ink absorbing surface of an ink absorber is not worn out or the ink absorbing surface is peeled off and the debris thereof does not clog the ejection ports of a recording head. This is the purpose.

[Means for Solving the Problems] To achieve the above object, an inkjet recording device of the present invention is provided with an inkjet recording device that is brought into contact with an ejection orifice surface of a recording head that performs recording by ejecting ink from an ejection orifice, and that the ejection orifice surface In the inkjet device, the wiper member includes a wiper member having elasticity for cleaning the ejection orifice surface by bending the wiper member by sliding relative to the ejection orifice surface. The ink absorber is provided with an ink absorber for absorbing unnecessary ink wiped by the provided wiper member, and the ink absorber is It is characterized by having an ink-absorbing surface coated.

Further, the recording head discharges ink using thermal energy, and some recording heads are equipped with an electrothermal converter for generating the thermal energy.

[Function] In the inkjet recording device of the present invention configured as described above, unnecessary ink adhering to the ejection orifice surface is wiped away by the wiper member, and a thin film covering the ink absorbing surface of the ink absorber is wiped away by the wiper member. The ink is carried onto the sliding surface of the plate-shaped covering member, passes through a plurality of through holes in the covering member, reaches the ink absorbing surface of the ink absorber, and is absorbed into the ink absorbing surface.

The covering member is fixed to the recording head and prevents the ink absorbing surface from protruding toward the recording medium.

[Example] Embodiments of the present invention will be described based on the drawings.

First, a first example will be described.

In FIG. 1, the inkjet recording apparatus 108 includes a carriage 111 carrying a recording head 1 coupled to a portion of a drive belt 112 that transmits the driving force of a drive motor 113, and two belts disposed parallel to each other. It is slidably fitted into book guide shirts l-114a and 114b, and the platen is moved so that the recording head l is opposed to the ejection opening surface la of the recording head l by the driving force of the drive motor 113. It is configured to reciprocate in the direction of arrow A and the opposite direction over the entire width of a recording paper (not shown), which is a recording medium fed onto the recording paper 115, to perform recording on the recording paper.

Further, the inkjet recording apparatus 108 of this embodiment is provided with a head recovery device 116, and the cap portion 116a of the head recovery device 116 is used for "distribution" within the range C of reciprocating movement of the recording head l during the recording operation. "area". ), facing the ejection port surface 1a of the recording head 1 at a position where the recording head 1 is moved during a head recovery operation (described later) (the left end of the guide shaft 114a in the figure, hereinafter referred to as the recovery position). is driven by the driving force of the motor 118 via the transmission mechanism 119 to record.
This caps the discharge port surface 1a of the rad 1.

This head rotation ffl device 116 includes the cap portion 1
16a caps the ejection opening surface 1a of the recording head 1, and the ink is sucked by an appropriate suction means or the ink is force-fed by an appropriate pressure means provided on the ink supply path to the recording head 1, and the ink is drawn into the recording head 1. A head recovery operation such as removing thickened ink from the ejection port 1b is performed by forcibly discharging the ink from the ejection port 1b (see FIG. 2 (see Al)).

A wiper member 2 made of an elastic plate-like member is fixed to a holding member 2a disposed on the right side of the head recovery device 116 in the drawing. This wiper member 2 has its tip protruding to an appropriate position beyond the moving path of the ejection port surface 1a of the recording head 1, and is attached to the ejection port surface 1a of the recording head 1 moving in the direction of arrow A or the opposite direction. The ejection port surface 1a of the recording head 1 is cleaned by sliding relative to the ejection port surface 1a while abutting and curving.

Further, a sensor 10 is disposed at an appropriate position on the left end of the guide shaft 114a in the figure, and when the sensor IO comes into contact with a portion of the carriage 111 that has moved in the six directions of arrows, the recording head l is moved. A reference position on the path is obtained, and the position of the recording head 1 on the movement path is obtained based on this reference position.

Next, an ink absorber for absorbing unnecessary ink wiped from the ejection port surface 1a of the recording head l by the wiper member 2 and a covering member that covers the ink absorbing surface of the ink absorber will be described.

As shown in FIG. 2 (A+ and iB), two ink absorbers 3 in the shape of a rectangular parallelepiped made of porous resin, etc.
4 is disposed such that its negative side is fixed to both sides of the recording head 1 (the side facing in the six directions of the arrows and the side opposite thereto). The rectangular ink absorbing surfaces 3a, 4a of the two ink absorbers 3, 4 are adjacent to both sides of the ejection port surface 1a, and extend from the ejection port surface 1a to the wall thickness of a covering member 5.6, which will be described later. They are formed parallel to the discharge port surface 1a at positions recessed by the same amount.

The thin plate-shaped covering members 5 and 6 that cover the entire surface of each of the ink absorbing surfaces 3a and 4a are made of a material having appropriate rigidity and wear resistance, and are designed to allow unnecessary ink wiped by the wiper member 2 to pass through. Thin through hole 5 large enough for
A, 6a are uniformly drilled in large numbers throughout. Further, one side of each covering member 5.6 is fixed to both sides of the discharge port surface 1a by a known fixing means,
Surfaces 5b and 6b (hereinafter referred to as "sliding surfaces") of each covering member 5 and 6 opposite to the surface that covers the ink absorbing surfaces 3a and 4a form the same plane as the ejection port surface 1a, respectively. .

Here, the operation of the recording head 1 when the recording head 1 passes in front of the wiper member 2 will be explained with reference to FIGS. 3 and 4.

The recording head 1 moves from the recording area on its movement path toward the recovery position in the six directions of the arrow, and is wiped by the wiper member 2 sequentially from the sliding surface 6b of the covering member 6 on the right side in the figure and the ejection port surface 1a. Collected unnecessary ink 7
It stops at a position where most of it is carried onto the sliding surface 5b of the covering member 5 on the left side in the figure (an example of which is shown in FIG. 3; hereinafter referred to as the "absorption position") (step Sl).

The stopped recording head 1 remains at the absorption position for a predetermined period of time, and during this time, the unnecessary ink 7 passes through each through hole 5a of the covering member 5 due to capillary action and is absorbed from the ink absorption surface 3a of the ink absorber 3. It is absorbed inside (step S2). The predetermined period of time is enough to finish absorbing the unnecessary ink 7 even when the ink absorber 3 becomes rich and absorbs the unnecessary ink 7 from the ink absorbing surface 3a at a slow rate.

The recording head 1 that has been on standby for the predetermined time starts moving again from the absorption position in the same direction (six arrow directions) as the moving direction before the stop (step S3). When the wiper member 2 leaves the sliding surface 5b of the covering member 5 and returns to its original shape, almost no unnecessary ink remains on the wiper member 2 and is scattered.

The operation described above is when the recording head 1 passes in front of the wiper member 2 in the direction of the arrow 6, but when the recording head 1 passes in front of the wiper member 2 in the opposite direction to the direction of the arrow 6. also operates in the same manner as described above.

The recording head 1 moves in the direction opposite to the direction of the six arrows, and most of the unnecessary ink that is wiped away by the wiper member 2 in order from the sliding surface 5b of the covering member 5 on the left side in the figure and the ejection port surface 1a is removed. Step Sl)
, waits for a predetermined time at the absorption position (step S2), and then starts moving again in the same direction as the movement direction before stopping (step S3).

In this embodiment, even if the ink absorbers 3 and 4 absorb unnecessary ink and expand, each ink absorbing surface 3a tends to protrude toward the recording medium side.

4a are restrained in their respective positions by respective covering members 5 and 6 fixed to the recording head l, so that, as in the conventional case, the recording medium is contaminated by the contact of each ink absorbing surface 3a, 4a with the recording medium. In addition, each ink absorbing surface 3a, 4a does not come into contact with the wiper member 2, so
Each ink absorbing surface 3a, 4a may be worn out, or each ink absorbing surface 3a may be damaged.

4a is peeled off and its debris does not clog the ejection port lb of the recording head l.

Next, a second embodiment of the present invention will be described.

As shown in FIG. 5, each F! Part 25.2
6 includes slit-like through holes 25a and 26a that extend long and narrow to both ends in a direction parallel to the direction in which the recording head 21 reciprocates on the movement path (arrow B direction and the opposite direction).
A large number of holes are drilled in parallel at appropriate intervals. however,
The opening size of each of the through holes 25a, 26a is such that even if each ink absorber 23, 24 absorbs unnecessary ink and expands, its respective ink absorbing surface 23a, 24a does not protrude. . Since the points other than those described above are the same as those in the first embodiment, the description thereof will be omitted.

To explain the third embodiment of the present invention, as shown in FIG. 6, each covering member 35 and 36 has A large number of slit-like through holes 35a and 36a are formed in parallel at appropriate intervals and extend vertically to the upper and lower ends in the figure. Since the points other than those described above are the same as those in the second embodiment, the description thereof will be omitted.

Next, a fourth embodiment of the present invention will be described.

As shown in FIG. 7, a plurality of recording heads 411 to 411 (hereinafter referred to as arbitrary number n) eject ink of one different color.
41. , is the direction in which the carriage (not shown) moves back and forth (
They are mounted on the carriage in parallel at equal intervals in the direction of the arrow and the opposite direction. n+1 ink absorbers 431 to 43n, and covering member 45. ~45. ．． ．．
．． have the same shape, and an ink absorber 431 and a covering member 45. are provided on the left side surface of the recording pad 411 located at the left end in the figure, with the same configuration as the first actual cover. is fixed to the recording head 4 located at the right end in the figure.
1. On the right side side in the figure, ink absorbers 43n, +g and a covering member 45. are provided with the same configuration as in the first embodiment. , , are fixed, and n recording heads 41 . ~41. Ink absorbers 43□-43n and covering members 452-45n are fitted between each of the recording heads 41. It is fixed to each side of ~41n. The rest of the configuration is the same as that of the first embodiment, so the explanation thereof will be omitted.

Here, there are n recording heads 41 . mounted on the carriage. ~41. The operation when the wiper members (not shown) sequentially pass in front of the wiper member (not shown) will be explained.

The carriage operates in the same manner as the recording head 1 of the first embodiment described with reference to FIGS.
1. Alternatively, when the recording head 41, . . . ) moves to its absorption position, it stops (step S1), waits for a predetermined time at the absorption position (step S2), and then starts moving in the same direction as before stopping (step S3). ), the operations from steps 5l to 53 are repeated for each of the printheads located next to the printhead (printhead 41. or printhead 41.) to the printhead located at the other end.

In this embodiment, the carriage performs the above-described series of operations so that each time the wiper member slides from the ejection port surface of one print head to the ejection port surface of the adjacent print head, the wiper member wipes the wiper member. Unnecessary ink is
Since the ink is absorbed by the ink absorber located between each print head, there is no possibility that inks of different colors adhering to the ejection orifice surface of each printhead will mix on the ejection orifice surface and cause an adverse effect. .

In this embodiment, the same effects as in the first embodiment can be obtained.

Next, a fifth embodiment of the present invention will be described.

As shown in FIG. 8, the two ink absorbers 5 of this embodiment
3.54i3 and the two covering members 5556 are attached to both upper and lower sides of the recording head 51 (in the direction of the arrow F, which is perpendicular to the direction of the arrow E, which is the direction in which the recording head 51 reciprocates on the movement path). The only difference from the first embodiment is that the first embodiment is fixed to each side (both sides facing each other), and the other configurations are the same.

The wiper member 52 is disposed at an appropriate position outside the recording area on the movement path of the recording head 51, and when the recording head 51 stops at the position, the wiper member 52
is configured to move back and forth in the direction of arrow F.

The operation of the wiper member 52 is basically the same as that of the recording head l of the first embodiment. The wiper member 52 is
The sliding surface of the covering member that has moved and is located on one side (sliding surface 5
5b or sliding contact surface 56b) and the ejection port surface 51a in order, and stop at the absorbing position where most of the collected unnecessary ink has been transferred onto the sliding surface of the covering member located on the other side. , waits at the absorption position for a predetermined time, and then starts moving again in the same direction as the movement direction before the stop.

Since the points other than those described above are the same as those in the first embodiment, the description thereof will be omitted. Furthermore, the same effects as in the first embodiment can be obtained in this embodiment.

The through-holes of the covering member of the present invention are not limited to those shown in the above-mentioned embodiments, and have a size and shape sufficient to allow unnecessary ink wiped by the wiper member to pass through, and have a sufficient size and shape to absorb ink. Any other material may be used as long as its ink absorbing surface does not protrude even when the body expands.

An example of a recording head equipped with an electrothermal transducer used in each of the embodiments described above will now be described. As shown in FIG. 9, in order to eject ink from a plurality of ejection ports 61b provided in a row in the recording head 61, an electrothermal transducer 616 that generates thermal energy is supplied with an applied voltage.
are arranged for each liquid path. By applying a drive signal, the electrothermal converter 61c generates thermal energy to cause film boiling and form bubbles in the liquid path. As the bubbles grow, each of the discharge ports 61b
The structure is such that ink is ejected from the ink.

The present invention brings about excellent effects particularly in the bubble jet recording head and inkjet recording apparatus proposed by Canon Co., Ltd. among inkjet recording systems.

Regarding typical configurations and principles, it is preferable to use the basic principles disclosed in U.S. Pat. No. 4,723,129 and U.S. Pat. No. 4,740,796. , continuous type, but especially in the case of on-demand type, electrothermal converters are placed corresponding to the sheet holding the liquid (ink) or the liquid path. By applying a single drive signal that corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling, thermal energy is generated in the electrothermal transducer, and the thermal effect of the rad on the recording is This is effective because it can cause bubbles to form in the liquid (ink) in one-to-one correspondence with this drive signal.The growth and contraction of these bubbles causes the liquid (ink) to flow through the ejection opening. The in-row is ejected to form at least one drop.If this drive signal is in the form of a pulse, bubble growth and contraction will occur immediately and appropriately.
Particularly responsive liquid (ink) ejection can be achieved,
More preferred. This pulse-shaped drive signal is described in U.S. Pat. Nos. 4,463,359 and 4,345,262.
Those described in the specification are suitable. Furthermore, if the conditions described in US Pat. No. 4,313,124 concerning the temperature increase rate of the heat acting surface are adopted, even more excellent recording can be achieved.

The configuration of the recording head includes, in addition to the combined configuration of ejection ports, liquid paths, and electrothermal converters (straight liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned specifications, a heat acting section. US Pat. No. 4,558,333 and US Pat. No. 4,459,600 disclose a configuration in which the
The present invention is also effective for the structure described in the specification. In addition, Japanese Patent Application Laid-Open No. 123670 of 1981 discloses a configuration in which a common snot is used as a discharge part for a plurality of electrothermal converters, and a hole absorbing pressure waves of thermal energy is disclosed. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461 of 1982, which discloses a configuration in which the discharge portion corresponds to the discharge portion.

In addition, a replaceable chip-type recording head or recording head that is attached to the inkjet recording device body enables electrical connection with the inkjet recording device body and supply of ink from the inkjet recording device body. The present invention is also effective when using a cartridge type recording head that is integrally provided with the recording head.

Furthermore, the recording mode of the inkjet recording device is not only a recording mode of only mainstream colors such as black, but also a recording mode of two or more different colors or a mixture of different colors, although the recording head may be configured integrally or by a combination of multiple heads. The present invention is also extremely effective for inkjet recording apparatuses equipped with one or more full-color inkjet recording apparatuses.

In each of the embodiments of the present invention described above, the ink is described as a liquid, but the ink is an ink that solidifies at low temperatures and becomes soft or liquid at room temperature. Since the temperature is generally controlled within a range of C or less so that the viscosity of the ink is within the stable ejection range, it is sufficient that the ink is in a liquid state when the recording signal is applied.

In addition, it is possible to actively prevent temperature rise due to thermal energy by using it as energy to transform the ink from a solid state to a liquid state, or to use ink that solidifies when left in order to prevent ink evaporation. In any case, it is also applicable to the present invention to use ink that is liquefied only by thermal energy, such as one in which the ink is liquefied by applying thermal energy in accordance with a recording signal and is ejected as liquid ink. be. In such a case, the ink is held in a liquid or solid state in the recesses or through holes of the porous sheet, as described in JP-A-54-56847 or JP-A-60-71260. It may also be in a form that faces the electrothermal converter.

In the present invention, the most effective method for each of the above-mentioned inks is to implement the above-mentioned film boiling method.

[Effects of the Invention] Since the present invention is configured as described above, it produces the effects described below.

Even if the ink absorber absorbs unnecessary ink and expands, the thin plate-shaped covering member fixed to the recording head and having a plurality of through holes will protrude toward the recording medium side of the ink absorber. Since the ink absorbing surface is suppressed, unlike conventional ink absorbers, the ink absorbing surface does not protrude and come into contact with the recording medium, thereby preventing the recording medium from being stained.

Furthermore, since the ink absorbing surface of the ink absorbing body and the wiper member do not come into contact with each other, the ink absorbing surface may be abraded by the wiper member, or the ink absorbing surface may be peeled off and debris may clog the ejection ports of the recording head. I never do.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention, and FIG. 2 is a diagram showing essential parts of the same embodiment, where fAl is a schematic perspective view of the ejection orifice surface of the recording head viewed from an oblique direction. FIG. 3 is an explanatory diagram for explaining the operation of the recording head of the same embodiment, FIG. 4 is a flowchart showing the operation of the recording head, and FIG. FIG. 6 is a schematic perspective view of the main parts of a recording head according to a second embodiment of the present invention, with the ejection orifice surface of the recording head of the third embodiment of the present invention viewed obliquely from the front. FIG. 7 is a schematic perspective view of the main parts of a recording head according to a fourth embodiment of the present invention, as seen from an oblique direction with the ejection orifice surface facing in front, and FIG. 8 is a schematic perspective view of main parts according to a fifth embodiment of the present invention. FIG. 9 is a schematic perspective view of the main part of the recording head used in each embodiment of the present invention, and FIG.
Figure 0 is a perspective view of the ink absorbing surface of a conventional ink absorber viewed from an oblique direction in front, Figure 11 is an explanatory diagram for explaining a conventional wiper member, and Figure 12 fA) and +Bl.
FIG. 2 is an explanatory diagram for explaining problems with a conventional ink absorber. 1.2+, 31, 41, ~41n, 5161...-recording head, Ia, 21a, 31a, 41a+
~41an51a--Discharge port surface, lb, 21b, 31b, 41b, ~41b. 51b, 61b...Discharge port, 2.52...Wiper member, 2a...Holding member, 3.4, 23, 24, 33, 34, 43, ~43, . 5
3.54--Ink absorber, 3a, 4a, 23a, 2
4a, 33a. 34a, 43a+ ~43an**, 53a, 54a
=-ink absorption surface, 5.6, 25, 26, 35, 36.45. ~45n,,
, 55.56--covering member, 5a 6a, 2
5a, 26a, 35a. 36a, 45a+ ~ 45a, ++, 55a, 56a・
...Through holes, 5b, 6b, 25b, 26b, 35b. 36b, 45b, ~45b, 55b, 56b・
... Sliding surface, 7... Unnecessary ink, IO... Sensor, 61c... Electrothermal converter. 108... Inkjet recording device, 111... Carriage, 112... Drive belt, 113... Drive motor, 114a, l l 4b -- Guide shaft, 11
5...Platen, 116...-Head recovery device, 118...Motor. 119...-Transmission mechanism. (A) A iPJ2 diagram, i! P110 figure 11 (A) M12 figure

Claims (1)

[Scope of Claims] 1. The ejection port surface is brought into contact with the ejection port surface of a recording head that performs recording by ejecting ink from the ejection port, and is curved by sliding relative to the ejection port surface. In an inkjet recording device having a wiper member including a plate-like member having elasticity for cleaning the discharge port surface, the wiper member is arranged adjacent to the ejection port surface and is arranged to absorb unnecessary ink wiped by the wiper member. An ink jet recording apparatus comprising an ink absorber, the ink absorbing surface of the ink absorber being covered with a thin plate-shaped covering member having a plurality of through holes fixed to the recording head. 2. The inkjet recording apparatus according to claim 1, wherein the recording head discharges ink using thermal energy, and includes an electrothermal converter for generating the thermal energy.