Ink jet recording method and apparatus for recovering ejection at a particular orifice by ejecting ink from adjacent orifices

An ink jet recording apparatus for performing recording by ejecting ink to a recording medium, has a recording head and head driving unit. To effect ejection recovery, the head driving unit drives selected ejection energy generating elements in the recording head so that ink is ejected from orifices which correspond to the selected ejection energy elements. The selected orifices include at least one orifice adjacent to a particular orifice at which ink ejection recovery is performed, but exclude the particular orifice in an arrangement of the plurality of orifices. This ejection recovery technique efficiently removes bubbles from the particular orifice.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an ink jet recording system which is used 
for outputting hard copies of information such as characters, images or 
the like in information processing machines such as copying machines, 
facsimiles, printers, word processors, personal computers and others, and 
more particularly, to a method and apparatus for recovering ink ejection 
of a recording head of the ink jet recording system. 
2. Description of the Related Art 
Ink jet recording apparatuses that perform ink ejection and invalve heat 
generation are known as types of ink jet recording apparatuses. There are 
two types of such ink jet apparatuses: one generates thermal energy for 
ejecting ink, that is, ejects ink by using the thermal energy; and the 
other incidentally generates heat accompanying the ink ejection. As an 
example of typical apparatuses of the former type there is known an 
apparatus that ejects ink on the basis of sudden generation of bubbles 
accompanying film boiling produced by thermal energy generated by 
electro-thermal converting elements that operate as ejection energy 
generating elements. This type of apparatus has advantages as follows: 
first, a large number of ink orifices and electro-thermal converting 
elements corresponding thereto can be easily disposed with high density; 
and second, the ink ejection response to the drive of the electro-thermal 
converting elements is quick, and hence high speed recording is possible. 
Thus, this type of apparatuses have been broadly used recently. As the 
other type of apparatus which incidentally generates heat accompanying the 
ejection, there is well known as apparatus that uses piezo-electric 
transducers as ejection energy generating elements. In this system, slight 
thermal energy is generated when the piezo-electric transducers oscillate 
for ejecting ink. 
In these ink jet recording apparatuses, the thermal energy for or during 
the ink ejection presents the following problems as already known. 
When comparatively high duty recording operations such as recording of 
visual images or images including solid portions are carried out in such 
an ink jet recording apparatus, a driving interval of the ejection energy 
generating elements becomes short. Thus, the next ejection of ink begins 
before extra heat generated with the ink ejection has been sufficiently 
dissipated. As a result, heat is stored in ink in ink passages in which 
ejection energy generating elements are disposed, thereby raising the 
temperature of the ink. In such a case, fine bubbles remaining in the ink 
passages will grow owing to the high temperature of the surrounding ink 
caused by the storing of heat during the recording, or owing to joining of 
fine bubbles. 
The remaining bubbles that grow to a certain size will effect the ejection 
behavior of ink in the ink passages: they can destabilize the ink ejection 
by modifying the direction and amount of the ejection. In addition, when 
such remaining bubbles further grow, they can block the ink passages, 
thereby hindering the ink ejection. The phenomenon that fine bubbles grow 
to such sizes as adversely effecting on ink ejection may take place not 
only by the storing of the heat, but also when the ink jet recording 
apparatus is left unused for a long time, or when particular orifices are 
not used for a long time period owing to the arrangement of data to be 
recorded. 
The fine bubbles remaining in the ink passages are produced when the ink 
therein is raised to a comparatively high temperature by the storing of 
the heat. In addition, in the apparatus which carries out ink ejection 
based on abrupt generation of bubbles by using thermal energy, a plurality 
of fine bubbles that do not serve to for ejection may be generated in 
conjunction with the bubbles that produce ejection, and may remain in the 
ink passages. Furthermore, when air is introduced into an ink tube for 
supplying ink from an ink reservoir to the recording head, the air will 
form fine bubbles in the ink passages remaining there. The comparatively 
fine bubbles remaining in the ink passages are partially expelled from the 
orifices by ink ejection during recording or by an idle ejection operation 
performed as one of the ejection recovery procedures. Some of the bubbles, 
however, may grow to a certain size when the heat is stored or when the 
apparatus is left unused for a long time, and may have an adverse effect 
on the ink ejection as described above. 
To prevent the above-mentioned harmful effects of the remaining bubbles, 
removal of the remaining bubbles from the ink passages has been 
conventionally carried out by expelling the ink in the passages as 
follows: the ink is forcibly sucked through the orifices by using a 
suction mechanism; or the ink is expelled by exerting pressure on the ink 
passages with a pressure mechanism. 
A comparatively large quantity of ink is expelled by the above-described 
suction or pressure operation, which can cause the undue consumption of 
the ink. As a result, the running cost of the recording apparatus 
increases. Moreover, the suction or pressure carried out during recording 
will reduce the recording speed of the apparatus because the suction or 
pressure operation requires comparatively many other operations such as 
moving the recording head to the capping position in addition to the 
suction or pressure operation itself. 
One characteristic construction of the recording head to be considered in 
the present invention will be described below in addition to the 
above-mentioned problem. 
The construction is common in recording heads which eject ink by using 
bubbles generated by the thermal energy. It comprises the following: a 
substrate that has electro-thermal converting elements that generate 
thermal energy by applying electric pulses (they are also called "drive 
pulses" later), electrode wiring for supplying power to the 
electro-thermal converting elements and so forth formed thereon with the 
IC fabrication technique; and a top plate that has grooves for forming ink 
passages in which the electro-thermal converting elements are disposed, 
and a common liquid chamber for storing ink to be supplied to the ink 
passages. The substrate and the top plate are joined together by adhesive 
bonding, thereby constituting the common liquid chamber, ink passages and 
orifices. 
This arrangement of the recording head has some problems concerning the 
adhesive bonding. First, the adhesives protrude into the ink passages or 
orifices, which will deviate the shapes of the ink passages or the 
orifices from the normal shapes, or block the ink passages or orifices. 
Second, the substrate or the top plate can deform or warp depending on the 
materials used, which will degrade the adhesive bonding. Third, the 
substrate and the top plate must be accurately adjusted, which makes 
complicates the fabricating process of the recording head. 
To overcome these problems, Japanese Laid-Open Patent Application No. 
2-192954 (or its corresponding European Patent Application Publication No. 
0,379,781) propose a recording head which obtains joining force of the 
substrate and the top plate with a pressure member such as a leaf spring. 
According to this arrangement, the adhesive can be obviated or limited to 
a least quantity needed, and hence the deformity of shapes of the ink 
passages or the orifices owing to the protrusion of the adhesives can be 
eliminated. Thus, the recording head failure causing the ink ejection 
failure can be prevented beforehand. Moreover, obviating the adhesives 
makes the alignment of the substrate and the top plate comparatively easy, 
thereby simplifying the fabrication process of the recording head. 
In the recording head ejecting ink by using thermal energy, the sudden 
generation of a bubble in the ink, that is, the sudden expansion and the 
subsequent compression of the bubble, is produced by driving the 
electro-thermal converting elements. In response to the expansion and 
compression of the bubble, pressure waves propagate in ink in the ink 
passages and common liquid chamber. The drive frequency of the 
electro-thermal converting elements is determined in response to drive 
data corresponding to characters or images to be recorded, and reaches 
several kHz in ordinary recording. 
When the electro-thermal converting elements are driven for ejecting ink 
and then the pressure waves of a certain frequency propagate through ink 
in the passages or the common liquid chamber, periodic forces caused by 
the pressure waves act on the substrate and the top plate that constitute 
the ink passages or the chamber. 
With regard to this, it has been confirmed that the following phenomenon 
took place: in the recording head which forms the joining force of the 
substrate and the top plate with the pressing member such as a leak 
springs, the oscillation of a certain frequency takes place owing to 
uneven forces which are caused by the pressure waves and the joining force 
of the pressing member, and act on the top plate and substrate. Such 
oscillation, once taking place, produces steady gaps at the rear portions 
of channel walls each of which separates each of ink passages where the 
joining force by the pressing member is comparatively small, that is, at 
the portions behind the electro-thermal converting elements in the ink 
passages. 
Furthermore, the substrate on which the electro-thermal converting elements 
are disposed has some unevenness because a plurality of layers are 
overlaid such as a layer for forming the electro-thermal converting 
elements, a protective layer thereof, or the like. In addition, some 
portions of the substrate and the top plate can have warped portions. 
These uneven or wrapped portions can cause thin gaps in the channel walls 
of the ink passages formed by joining the substrate and the top plate. 
These gaps will be enlarged by the oscillation mentioned above. Thus, the 
ink passages will communicate each other through the gaps generated or 
formed. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide a method for 
recovering ink ejection of a recording head of an ink jet recording 
apparatus and an ink jet recording apparatus that can recover the ink 
ejection by consecutively ejecting ink from orifices connected to the ink 
passages which include at least the ink passage adjacent to the ink 
passages that contains bubbles to be expelled, buy which exclude the ink 
passage that contain bubbles to be expelled, thereby expelling the bubbles 
in the ink passage. 
It is another object of the present invention to provide a method for 
recovering ink ejection of a recording head of an ink jet recording 
apparatus and an ink jet recording apparatus that positively utilizes gaps 
in the channel walls between the ink passages to expel remaining bubbles 
in the ink passages. In particular, in a recording head in which a 
substrate and a top plate are joined and fastened with a pressure member 
such as leaf springs, there is provided a method for recovering ink 
ejection of a recording head of an ink jet recording apparatus and an ink 
jet recording apparatus that can recover the ink ejection by consecutively 
ejecting ink from orifices connected to the ink passages which include at 
least the ink passages adjacent to ink passages that contain bubbles to be 
expelled, but which exclude the ink passage that contain bubble to be 
expelled but which exclude the ink passage that contain bubble to be 
expelled, thereby drawing bubbles to be expelled into the adjacent ink 
passages via the gaps, and expelling the bubble in the ink passages with 
ink ejection. 
In a first aspect of the present invention, there is provided a method for 
performing an ink ejection recovery in an ink jet recording apparatus 
having a recording head which comprises a plurality of orifices, a 
plurality of ink passages each of which correspondingly communicates with 
each of the plurality of orifices and is provided with an ejection energy 
generating element, and a common liquid reservoir communicating with each 
of the plurality of ink passages, and performing recording by ejecting ink 
to a recording medium, the method comprising the step of: 
ejecting ink from orifices by driving the ejection energy generating 
elements of the orifice continuously for predetermined times, the orifices 
including at least one orifice adjacent to an aimed orifice at which the 
ink ejection recovery is performed, but excluding the aimed orifice in an 
arrangement of the plurality of orifices. 
In a second aspect of the present invention, there is provided a method for 
performing an ink ejection recovery in an ink jet recording apparatus 
having a recording head which comprises a plurality of orifices, a 
plurality of ink passages each of which correspondingly communicates with 
each of the plurality of orifices and is provided with an ejection energy 
generating element, a first substrate and a second substrate for forming 
the plurality of ink passages by joining the second substrate to the first 
substrate, and a joining member for press joining the first substrate and 
the second substrate by means of line pressure applied to the first 
substrate and/or the second substrate, the method comprising the step of: 
ejecting ink from orifices by driving the ejection energy generating 
elements of the orifices continuously for predetermined times, the 
orifices including at least one orifice adjacent to an aimed orifice at 
which the ink ejection recovery is performed, but excluding the aimed 
orifice in an arrangement of the plurality of orifices. 
According to one aspect of the present invention, there is provided an ink 
jet recording apparatus for performing recording by ejecting ink to a 
recording medium, comprising: 
a recording head having a plurality of orifices, a plurality of ink 
passages each of which correspondingly communicates with each of the 
plurality of orifices and is provided with an ejection energy generating 
element, and a common liquid reservoir communicating with each of the 
plurality of ink passages; and 
head driving means for driving the ejection energy generating elements so 
that ink is ejected from orifices each of which corresponds to each of the 
ejection energy generating elements, the orifices including at least one 
orifice adjacent to an aimed orifice at which an ink ejection recovery is 
performed, but excluding the aimed orifice. 
According to a more specific aspect of the invention, there is provided an 
ink jet recording apparatus for performing recording by ejecting ink to a 
recording medium, comprising: 
a recording head having a plurality of orifices, a plurality of ink 
passages each of which correspondingly communicates with each of the 
plurality of orifices and is provided with an ejection energy generating 
element, a first substrate and a second substrate for forming the 
plurality of ink passages by joining the second substrate to the first 
substrate, and a joining member for press joining the first substrate and 
the second substrate by means of line pressure applied to the first 
substrate and/or the second substrate; and 
head driving means for driving the ejection energy generating elements so 
that ink is ejected from orifices each of which corresponds to each of the 
ejection energy generating elements, the orifices including at least one 
orifice adjacent to an aimed orifice at which an ink ejection recovery is 
performed, but excluding the aimed orifice. 
The above and other objects, effects, features and advantages of the 
present invention will become more apparent from the following description 
of the embodiments thereof taken in conjunction with the accompanying 
drawings.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
The invention will now be described with reference to the accompanying 
drawings. 
FIRST EMBODIMENT 
FIG. 1 is a schematic sectional view showing a part of a recording head for 
explaining an ejection recovery procedure of a first embodiment of the 
present invention, and FIG. 2 is a schematic sectional view showing the 
state of remaining bubbles in a recording head to which a bubble expelling 
procedure of the present invention is applied. 
In FIG. 2, a plurality of electro-thermal converting elements 1.sub.1 
--1.sub.n which is disposed in ink passages 2.sub.l --2.sub.n 
respectively, generate thermal energy. In each of ink passages 2.sub.l 
--2.sub.n, a sudden expansion and a subsequent compression of the bubble 
can be produced at the vicinity of the electro-thermal converting element 
so that ink is ejected from respective orifices N.sub.1 --N.sub.n. the ink 
passages 2.sub.1 --2.sub.n are supplied with ink from a common liquid 
chamber 3 storing the ink in accordance with ink ejection. 
FIG. 2 shows the state of bubbles remaining in the ink passages 2.sub.l 
--2.sub.n after two pieces of recording paper have been fully recorded in 
sequence: bubbles growing to considerable sizes are remaining in the ink 
passages. Such bubbles which have grown and remain in the ink passages 
generally decrease their sizes owing to cooling by surrounding ink. 
Bubbles which have grown beyond a certain size, however, require 
comparatively long time until disappearing, and they sometimes remain 
until the next recording is carried out. When recording is carried out in 
such a state, instability of ejection of ink may take place as previously 
described, deteriorating the quality of recorded images. Furthermore, when 
the recording apparatus is left in a comparatively high temperature 
atmosphere or is left unused for a long time at the state in which bubbles 
have grown beyond a certain size, the bubbles will grow still greater, 
thereby blocking the ink passages, which sometimes stops the ejection of 
ink. 
A procedure for expelling bubbles which may have the adverse effect on the 
ink ejection will be described below. In FIG. 1, a bubble, which has been 
remaining in a particular ink passages 2.sub.k at the center of the 
figure, can expelled from the orifice N.sub.k as follows: first, 10-100 
times of ejections of ink from the adjacent orifice N.sub.k-1 are carried 
out by applying electric pulses to the electro-thermal converting element 
1.sub.k-1 ; second, similar times of ejections of ink from the other 
adjacent orifice N.sub.k+1 are carried out by applying electric pulses to 
the electro-thermal converting elements l.sub.k+1. These pulses take place 
at a predetermined frequency, and each of the m has the same energy as 
that of the pulses used in the recording operation. 
Alternatively, ejections from the orifices N.sub.k-1 and N.sub.k+1 similar 
to those of the above followed by further 10-100 times of ejections from 
the orifice N.sub.k-1 can achieve a more effective expulsion of the 
bubble. 
Furthermore, the ejection operation described above in which ejections from 
the orifices N.sub.k-1 and N.sub.k+1 are sequentially performed can be 
repeated a plurality of times. 
In addition, to ensure the expulsion of bubbles, the ink ejection from the 
adjacent orifices as described above may be followed by the ink ejection 
from the orifice from which the bubbles must be expelled. In this case, 
the operation is carried out as follows: first, bubbles remaining in an 
aimed or particular ink passage are usually expelled therefrom by the ink 
ejection from the adjacent ink orifices; and second, a comparatively large 
bubble, which may remain near an aimed orifice owing to meniscus 
associated with the bubble, is expelled with ink ejected from the aimed 
orifice connected to the aimed ink passage by driving the electro-thermal 
converting element thereof. 
In these cases, it is not preferable that the electro-thermal converting 
elements 1.sub.k-1 and 1.sub.k+1 are driven at the same frequency as that 
of the recording operation because at this frequency the temperature rise 
by the stored heat so that bubbles will grow in the liquid passages 
2.sub.k-1 and 2.sub.k+1 containing these electro-thermal converting 
elements. To prevent this, it is preferable that ink ejections from the 
adjacent orifices N.sub.k-1 and N.sub.k+1 are performed at a lower drive 
frequency than that of the recording operation so that the thermal 
diffusion takes place during the intervals between the pulses and hence 
the bubbles do not grow. In this example, the drive frequency of the 
recording operation is 4 kHz and that of the bubble expulsion is lower 
than 2 kHz and preferably below 1 kHz. 
Furthermore, the drive frequency can be altered: for example, when the 
ejection operation in which ejections from the orifices N.sub.k-1 and 
N.sub.k+1 are sequentially performed is repeated a plurality of times, the 
drive frequency can be decreased as the repetition time increases. By 
using such a technique, remaining bubbles of various sizes can be 
effectively expelled in accordance with their sizes because it is supposed 
that comparatively large remaining bubbles are effectively expelled by 
driving with relatively high frequencies, and comparatively small 
remaining bubbles are effectively expelled by driving with relatively low 
frequencies. Moreover by gradually reducing the frequencies, the 
temperature rising of the recording head associated with the ink ejection 
of the ejection recovery procedure can be prevented. Incidentally, the 
drive frequencies can be changed in accordance with the time of non 
recording, recording duty, or indices indicating the sizes of bubbles. The 
ejection operation in which the drive frequencies are changed is effective 
for all the ink ejections in the ejection recovery of the present 
embodiment. 
In the above bubble expelling operation, bubbles are expelled by 
sequentially ejecting ink from both the adjacent orifices. The expulsion 
of the bubble, however, can be accomplished by expelling ink from one of 
the two adjacent orifices. A simultaneous ink ejection from both the 
adjacent orifices, however, are more effective, and can shorten the time 
required for the expulsion of bubbles. 
A hypothetical principles of the bubble expulsion as described above will 
be described with reference to FIG. 1. In FIG. 1, the simultaneous ink 
ejections are carried out from the orifices N.sub.k-1 and N.sub.k+1 
adjacent to the orifice N.sub.k from which a bubble must be expelled. The 
principle of the bubble expulsion is thought to be as follows: Continuous 
ink ejections from the orifices N.sub.k-1 and N.sub.k+1 generate ink 
currents from the common liquid chamber 3 to the ink passages 2.sub.k-1 
and 2.sub.k+1 as shown by arrows in FIG. 1. The ink currents will increase 
the ink pressure near the boundaries between the ink passage 2.sub.k and 
the common liquid chamber 3. This will produce in the ink passage 2.sub.k 
a pressure slope which is higher on the side of the common liquid chamber 
and is lower on the side of the orifice N.sub.k. The pressure slope will 
generate force (a kind of buoyant force in its broad sense) toward the 
orifice N.sub.k, which acts on the bubble remaining in the ink passage 
2.sub.k, thereby moving the bubble to the orifice N.sub.k. 
As an alternative hypothetical principle, the bubble expulsion is supposed 
to take place as follows: When the bubbles for ink ejection are generated 
in the adjacent ink passages 2.sub.k-1 and 2.sub.k+1, the sudden expansion 
of the bubbles produces pressure waves in the ink pressure 2.sub.k-1 and 
2.sub.k+1, and the pressure waves propagate toward the orifices N.sub.k-1 
and N.sub.k+1 as well as toward the common liquid chamber 3. The pressure 
waves propagate to the common liquid chamber 3 where they make reflection 
and interference, and subsequently travel to other ink passages. Although 
the pressure waves are little attenuated during travelling in the ink 
passages where they are generated, they are weakened in proportion to the 
square of distances from the ink passages when they propagate in the 
common liquid chamber. For this reason it is supposed that the pressure 
waves produced in the ink passages 2.sub.k-1 and 2.sub.k+1 propagate to 
the adjacent ink passage 2.sub.k with a considerable intensity, and that 
the pressure waves expel the remaining bubbles when the waves propagate in 
the ink passages 2.sub.k toward the orifice N.sub.k. Alternatively, it is 
assumed that the propagation of the pressure waves causes a pressure slope 
in the ink passages as in the principle described before, and this 
pressure slope expels the remaining bubbles. Still alternatively, it may 
be supposed that the bubble expulsion by the pressure waves operates in 
conjunction with the bubble expulsion by the pressure slope caused by the 
ink flow as described above, thereby expelling the remaining bubbles. 
As a third hypothetical principle, it is supposed that the remaining 
bubbles are expelled by the ink flow toward the orifice N.sub.k, which 
flow is produced by the pressure inclination in the ink passage 2.sub.k. 
In the ejection recovery procedure described above, the bubble expulsion is 
carried out by ejecting ink from only the adjacent orifices. Ejection of 
ink, however, may be performed from other orifices at the same time: for 
example, in FIG. 2, simultaneous ink ejections from the orifices N.sub.1 
and N.sub.2 and orifices N.sub.4 and N.sub.5 may be carried out to expel a 
bubble in the ink passages 2.sub.3. The ink ejections not only from the 
adjacent orifices but also from other orifices will improve the effect of 
bubble expulsion. 
Furthermore, another ejection recovery procedure using the bubble expelling 
procedure described above is performed as follows. When the recording 
apparatus is left unoperated for a long time, ink will vaporize from the 
orifices, thereby increasing the viscosity of the ink in the ink passages 
and the remaining bubbles grow. This will hinder the normal ejection of 
ink, and sometimes causes orifice clogging. In such cases the following 
steps are taken: first, high duty ink ejections, that is, driving the 
electro-thermal converting elements with high frequency are carried out to 
elevate the temperature in the ink passages so as to lower the viscosity 
of the ink therein, thus discharging the highly concentrated ink; after 
that, the ink ejections with frequency lower that above frequency are 
carried out. Such ink ejection operation is performed in such manner that 
alternate continuous ejections from the odd number orifices and from the 
even number orifices in a series of orifices are carried out to further 
expel the high concentration ink in the ink passages, and at the same time 
to expel the remaining bubbles therein. Thus, the normal ejection of ink 
becomes possible, and hence the recording apparatus which has been left 
unoperated for a long time can provide stable, high quality images. 
Further ejection recovery procedure will now be described. 
In FIG. 2, 10-100 times of continuous ejections from each respective 
orifices N.sub.l -N.sub.n of the head are carried out in sequence. This 
method has an advantage that the checking that if each orifice normally 
ejects ink can be achieved simultaneously during the ink ejection for 
expelling the remaining bubbles in each orifice. 
In addition, this method is effective for expelling bubbles; for example, 
let us suppose that the head has 64 orifices; in this case, by sequential 
ejections from all the orifices 1-64, followed by several times 
repetitions of the sequential ejections, the remaining bubbles are 
expelled from each orifice. During this operation, it will be very 
effective in expelling bubbles if the intervals of continuous ejections 
from each orifice are changed in such a fashion that the intervals are set 
longer at first and then are gradually shortened as the repetitions 
proceed. 
The ejection recovery procedures described above are also effective as the 
idle ejection which is carried out when continuous high duty recording 
operations are performed and hence heat is stored in the each ink passage. 
Furthermore, the ejection recovery procedures, when applied to the 
recording apparatuses of printers, facsimiles or the like, can be 
performed during waiting times for recording commands, or during data 
transmission, which can prevent a decline of recording speed of the 
recording apparatus. 
When the ejection recovery procedures are applied to copying machines, they 
can be achieved after a high duty recording operation, or during intervals 
between recording operations of respective pieces of recording paper. 
Thus, continuous, high quality recording of images can be achieved without 
other procedures such as suction or the like. 
FIG. 3 is a perspective view showing an arrangement of an example of an ink 
jet recording apparatus to which the ejection recovery procedures can be 
applied. 
In FIG. 3, reference numeral 14 designates a recording head cartridge 
having a recording head chip and an ink tank which are constructed into 
one body. Here, the recording head chip has orifices for ejecting ink, and 
electro-thermal converting elements as energy generating elements 
corresponding to the orifices. The ink tank functions as an ink supply. 
The head cartridge 14 is fixed on a carriage 15 by means of a pressing 
member (fixing lever) 41, and these components 14 and 15 can move to and 
fro in the longitudinal directions along shafts 21. The ink ejected from 
the orifices of the recording head chip reaches a recording paper 18 as a 
recording medium which is regulated by a platen roller 19 disposed against 
the orifices via slight space, thereby to form an image on the recording 
paper 18. 
The electro-thermal converting elements disposed in the recording head chip 
are supplied from a data supplying source with ejection signals 
corresponding to image data via a cable 16 and terminals connected 
thereto. Only one head cartridge 14 is provided in this example. 
In FIG. 3, reference numeral 17 designates a carriage motor for driving the 
carriage 15 along the shafts 21, 22, a wire for transmitting the drive 
force of the motor 17 to the carriage 15, 20, a feed motor for conveying 
the recording paper 18 in conjunction with the platen roller 19. 
Reference numeral 25 denotes a capping member which is disposed at a 
position corresponding to the home position of the carriage 15, and which 
can cover an orifice-disposed face of the heat chip on which the orifices 
are disposed. The capping member 25 prevents drying or caking involved in 
the drying of ink near the orifices. To the capping member 25 is connected 
via a tube 4 a pump 30 for eliminating an ejection failure. When the pump 
30 is driven for eliminating the ejection failure, ink is sucked from the 
orifices by the sucking force caused by the pump 30. The ejection recovery 
procedure by sucking as a different mode from the bubble expelling 
procedure is carried out for removing high viscosity or hardened ink near 
the orifices. Such high viscosity or hardened ink appears when 
non-recording state continues for a long time or when particular orifices 
are not used for a long time owing to the arrangement of printed images. 
The capping member 25 is provided with a member for receiving ink ejected 
for a long time recovery procedures. 
Adjacent to the capping member 25, a blade 5 is disposed in such a manner 
that it can project toward the region where the recording head can move. 
The blade 5 is used to wipe the orifice disposed face after the ejection 
recovery procedure or the like so that wet or paper particulate 
contaminants are removed therefrom. 
FIG. 4 is a perspective view of the recording head cartridge 14 of the 
embodiment as shown in FIG. 3. The head cartridge 14 is a detachable type 
incorporating an ink tank 110 that functions as the ink supply, and a 
recording head chip 101. The recording head chip 101 is exchanged for new 
on in company with the exchange of the head cartridge 14 when ink in the 
ink tank is spent. 
The recording head chip 101 comprises the following: a plurality of 
orifices N aligned on a surface opposite to the recording medium; a 
plurality of ink passages (not shown) each of which extends inside each of 
the orifices respectively electro-thermal converting elements (not shown) 
each of which is disposed in each of the ink passages; and a common liquid 
chamber (not shown) communicating to the respective ink passages. A supply 
reservoir portion 104 functions as a sub-reservoir that receives ink from 
the ink tank 110 and guides the ink into the common liquid chamber in the 
recording head chip 101. 
The ink reservoir 110 contains a ink absorber 112, which is made of porous 
material or of fibers or the like, for impregnating ink. The ink tank 110 
has a lid 114. 
FIG. 5 is a block diagram showing an arrangement of a control portion of 
the apparatus as shown in FIG. 3. The control portion controls the 
ejection recovery procedures described above. 
In FIG. 5, a CPU 200 processes various signals for controlling the 
apparatus. The CPU 200 is connected to an RAM 200A which is used as work 
areas or for other purposes during the processing, and to an ROM 200B that 
stores drive data, processing procedures, etc., for controlling the 
ejection recovery procedures described above. During the ejection recovery 
procedure, the CPU 200 supplies a head driver 101A with the following data 
according to the processing procedures stored in the ROM 200B: selection 
data for selecting orifices to perform ejection; pulse width data for 
determining the width of the electric pulses; and drive frequency data for 
determining the drive frequency of the electro-thermal converting 
elements. 
In addition, the CPU 200 supplies necessary data to a carriage motor driver 
17A and a paper feed motor driver 20A to drive a carriage motor 17 and a 
paper feed motor 20, thereby controlling the moving of the carriage 15 and 
the feeding of the recording paper 18. 
FIG. 6 is a perspective view showing an example of an ink jet recording 
apparatus that can achieve a full-color recording. With such an apparatus 
provided with a plurality of recording heads, the ejection recovery 
procedures of the present invention can reduce the number of ink suction 
procedures for ejection recovery. This makes it possible to save ink which 
is otherwise spent by the suction procedures. 
SECOND EMBODIMENT 
A second embodiment of the present invention relates to an ink expulsion 
procedure which positively utilizes the gaps in the channel walls forming 
the ink passages of the recording head. When a common recording head is 
built, the substrate and the top plate are joined by adhesive bonding so 
that the gaps are not procedure in the channel walls between the ink 
passages. In this case, placing of adhesives and the arrangement for 
producing joint force must be carefully carried out. In contrast with 
this, in a recording apparatus that joints the substrate and the top plate 
by means of plate springs to simplify the construction as mentioned above, 
gaps may be produced in channel walls separating the ink passages. The 
second embodiment positively utilizes the gaps to eliminate remaining 
bubbles. 
FIG. 7 is a schematic sectional view showing a part of a recording head for 
explaining a hypothetical principle of the second embodiment of the 
present invention. 
In FIG. 7, a bubble, which has been remaining in the ink passage 2.sub.k at 
the center of the figure and may have adverse effect to the ink ejection, 
can be expelled from the orifice N.sub.k-1 or N.sub.k+1 as follows: first, 
10-100 time of ejections of ink from the adjacent orifice N.sub.k-1 are 
carried out by applying electric pulses to the electro-thermal converting 
element 1.sub.k-1 ; second, similar times of ejections of ink from the 
other adjacent orifice N.sub.k+1 are carried out by applying electric 
pulses to the electro-thermal converting element 1.sub.k+1. These pulses 
take place at a predetermined frequency, and each of the m has the same 
energy as that of the pulses used in the recording operation. 
Alternatively, ejections from the orifices N.sub.k-1 and N.sub.k+1 similar 
to those of the above followed by further 10-100 times of ejections from 
the orifice N.sub.k-1 can achieve a more effective discharge of the 
bubble. 
In this case, the electro-thermal converting elements 1.sub.k-1 and 
1.sub.k+1 are driven at same frequency as that of the first embodiment. 
In the above bubble expelling operation, bubbles are expelled by 
sequentially ejecting ink from both the adjacent orifices. The expulsion 
of the bubble, however, can be accomplished by expelling ink from one of 
the two adjacent orifices. 
Now, one conceivable principle underlying the phenomenon of the expulsion 
of bubbles as described above will be explained referring to FIG. 7. FIG. 
7 is a view illustrating the case where ink is ejected simultaneously from 
both of orifices N.sub.k-1 and N.sub.k+1 which are adjacent to the orifice 
N.sub.k connecting to an ink passages 2k from which bubbles must be 
expelled. In this case, the phenomenon is considered to be based on the 
following principle. Ink refill resulting from the continuous ink ejection 
from a respective one of the ejection outlets N.sub.k-1 and N.sub.k+1 
provided on both sides of the ink passages 2k causes ink streams flowing 
from the common liquid chambers 3 to ink passages 2.sub.k-1 and 2.sub.k+1 
as arrowed in FIG. 7. These ink streams give rise to further ink streams 
as shown by arrow S through gaps which occur at the channel walls 
W.sub.k-1 and W.sub.k due to pressure waves or the like when the ink is 
being ejected. The bubbles staying in the ink passages 2.sub.k are sucked 
into the ink passages 2.sub.k-1 or 2.sub.k+1 through the channel walls 
W.sub.k-1 or W.sub.k due to the ink streams S flowing through the gaps, 
and at the same time, expelled from the ejection outlets N.sub.k-1 or 
N.sub.k+1 concurrently along with the ink ejection through the ink 
passages. 
The ejection from the adjacent ink passages performed only once rarely 
allows bubbles to be sucked. A plurality of continuous ejection operations 
allow bubbles to be gradually sucked through the gaps. It is considered 
that initial positions of bubbles and extent of the gaps are factors that 
determine which one of the adjacent ink passages sucks the bubbles in the 
case where the ejection operations are simultaneously performed from both 
of the adjacent ink passages. 
In the bubble expelling procedure in accordance with this embodiment, the 
number of the ejection outlet for ejection and a period when the 
continuous ejection operations are repeated are set in a like manner as 
explained with reference to the first embodiment. Further, this embodiment 
attains substantially the same results as those of the first embodiment. 
Next, the following explanations relate to a recording head which is 
suitable for performing the bubble expelling procedure according to the 
second embodiment of the present invention as described above, and one 
example of an ink jet recording apparatus employing the recording head. 
This recording head has a simple structure, leading to relatively low 
manufacturing cost. A further advantage is that the recording head is 
capable of reliably discharging staying bubbles out of ink passages with 
effectiveness by utilizing mutual interference between the adjacent ink 
passages as is generally thought to be disadvantageous. More specifically, 
the recording head may be of a structure such that two members of the top 
plate and the substrate are joined together by pressure (or also the two 
members maybe joined together by partially applying an adhesive to some 
portions thereof), the top plate having grooves for forming the ink 
passages and the common liquid chamber, the substrate having the 
electro-thermal converting elements formed therein. Here, the grooves 
forming ink passages or the like and the electro-thermal converting 
elements may be formed on either of the ceiling plate or the substrate. 
Now, one embodiment will be described below having a structure which 
permits the force produced by pressure as described above to uniformly 
exercise corresponding regions covering the electro-thermal converting 
elements and the orifices of the recording head, particularly areas 
extremely near to the orifices. In order to achieve the press joining of 
the members by applying the uniform force as described above, line 
pressure is utilized. A few examples of the recording head having such 
structure as described above will be shown below. 
A first example of the recording head has orifices for ejecting ink, ink 
passages communicating with the orifices, and an ejection energy 
generating element which are disposed on predetermined positions of the 
ink passages, for example an electro-thermal converting elements, for 
generating energy for ejecting ink, in which a first and second substrates 
where the ink passages and the orifices are formed are press joined by a 
line pressure pressing member for generating line pressure. 
A second example of the recording head has a first substrate having 
ejection energy generating elements for generating energy for ejecting ink 
from orifices, a second substrate having recesses and projections for 
forming ink passages communicating with the orifices when the second 
substrate is joined with the first substrate and a leaf spring member for 
mechanically joining the first substrate with the second substrate, in 
which the first and second substrates are press joined by line pressure 
produced by an end portion of a bent projection of the leaf spring. 
A third example of the recording head comprises a first substrate having 
ejection energy generating element for generating energy for ejecting ink 
from orifices, a second substrate having an orifice plate having the 
orifices, a front plate member being formed integral to the orifice plate 
and having a portion projecting outwardly, and recesses and projections 
which are formed integral thereto and form ink passages communicating with 
the orifices when the second substrate is joined with the first substrate, 
and a leaf member spring for mechanically press joining the first and 
second substrates, in which the first and second substrates are press 
joined by line pressure produced by an end portion of a bent projection of 
the leaf spring member outer face of which is in contact with a surface of 
the front plate member, the surface facing an opposite direction to a 
direction in which ink is ejected. 
In accordance with the structures as described above, in press joining the 
first substrate and the second substrate, the contact surface of the leaf 
spring member which contacts the second substrate (top plate) is made 
linear so as to produce concentrated joining force so that a region of the 
second substrate covering the ink passages in the vicinity of the orifices 
is preferred by substantially uniform pressure. With this arrangement, an 
relative vibration between the first substrate and the second substrate is 
caused by the ink ejection so that the second substrate oscilatorilly 
separates from the first substrate. As a result, gaps between the channel 
walls of the ink passes is formed so that bubbles are expelled through the 
gaps as described above. 
FIG. 8 through FIG. 12 show an embodiment of the recording head with its 
structure described above and the ink jet recording apparatus using this 
recording head. In the following descriptions, each component structure of 
the ink jet recording head and the ink jet recording apparatus is 
explained with these drawings. 
The recording head carriage IJC in this embodiment, as shown in FIG. 9, has 
an ink tank IT which has a relatively large capacity for receiving ink and 
the recording head unit IJU integrally. The recording head unit IJU has 
such a shape that a top portion of the recording head unit IJU sticks out 
from the front face of the ink tank IT. This recording head cartridge IJC 
is fixed and supported by locating means and an electric contact member 
described later, of the carriage HC as shown in FIG. 11 which is provided 
with the ink jet recording system IJRA. In this arrangement, the recording 
head cartridge IJC can be exchanged when ink in the ink tank IT is spent 
completely. This means that the recording head unit IJU is also exchanged. 
(i) The construction of the recording head unit IJU 
The recording head unit IJU in this embodiment has a recording head using 
an ink ejection mechanism where in response to input electric signal, an 
electro-thermal converting element generates thermal energy to produce 
film boiling in the ink so that the ink ejection is carried out by the 
formation of a bubble caused by the film boiling. 
In FIG. 8, reference numeral 100 denotes a heater board or substrate. The 
heater board 100 is composed of electro-thermal converting elements 
(ejection heaters) arranged in an array geometry on a silicon substrate 
plate and electric wiring supplying powers to the electro-thermal 
converting elements formed with a film forming technology. Reference 
numeral 1200 denotes a distribution substrate connecting to the heater 
board 100, containing wirings to the heater board 100 (both ends of the 
wirings, for example, are fixed by wire bonding) and pads 1201 locating at 
one end of the wiring from the heater board 100 for transferring electric 
signals from the host apparatus of the ink jet recording apparatus. 
Reference numeral 1300 denotes a top plate with grooves which are provided 
for forming separation walls for defining individual ink passage, a common 
fluid reservoir and so on. In addition, the top plate 1300 is a molded 
unit with an ink inlet 1500 for pouring ink supplied from the ink tank IT 
into the common fluid reservoir and an orifice plate 400. Though the 
preferable material for the molded unit is polysulfone, another kind of 
molding resin may be acceptable to be used. 
Reference numeral 300 denotes a support member, for example, made of metal, 
supporting the reverse side of the distributing substrate 1200 by meeting 
their flat faces together, defining a bottom of the recording head unit 
IJU. Reference numeral 500 denotes a leaf spring shaped like a letter M. 
The leaf spring 500 process a certain portion of the top plate 1300 which 
is corresponds to the fluid reservoir of the center of the letter M and at 
the same time its project portion 501 which projects at the side portion 
of the leaf spring 500 also presses a portion of the top plate 1300 which 
is corresponds to the ink passages. The press of the project portion 501 
is such that the pressure force is concentrated on a line which is defined 
by the end of the project portion 501. Legs of the leaf spring 500 
penetrate through the holes 3121 at the support member 300 and are fixed 
in the reverse side of the support member 300 so that the heater board 100 
and the top plate 1300 are held between the leaf spring 500 and the 
support member 300 rebound force. That is, the heater board 100 and the 
top plate 1300 can be fixed and contacted to each other by the rebound 
force generated with the leaf spring 500 and its project portion 501. 
The support member 300 has locating holes 312, 312, 1900 and 2000 into 
which two protruding portions 1012, 1012 for locating and protruding 
portions 1800, 1801 for locating and supporting by fusion are inserted 
respectively. These protruding portions 1012, 1012, 1800 and 1801 are 
formed on the side wall of the body of the ink tank IT. The support member 
300, in its rear side, has also protruding portions 2500 and 2600 for 
locating the recording head cartridge IJC on the carriage HC in the ink 
jet recording apparatus IJRA. In addition, the support member 300 has a 
hole 320 through which an ink supply pipe 2200 as disclosed later for 
supply ink to a recording head IJC from the ink tank IT. The distributing 
substrate 1200 is bound on the support member 300 by bonding materials or 
the like. There are a couple of concave portions 2400, 2400 on the support 
member 300 in the neighborhood of the locating protruding portions 2500 
and 2600. In the ink jet cartridge IJC as shown in FIG. 9, the concave 
portions 2400, 2400 are also located on the extension of the line from the 
apex portion of the recording head unit IJU, three sides of which are 
defined in portion having a plurality of parallel grooves 3000 and 3001. 
Therefore, the concave portions 2400, 2400 make it possible to keep 
unfavorable dust and ink sludge away from the protruding portions 2500 and 
2600. On the other hand, as illustrated in FIG. 8, a cover plate 800 on 
which the parallel grooves 3000 are formed forms an outer wall of the 
recording head cartridge IJC and accommodates the recording head unit IJU. 
In an ink supply member 600 having other parallel grooves 3001 includes an 
ink pipe 1600 which is arranged as a cantilever with its fixed end being 
on the side of the ink supply pipe 2200 and is connected to the ink supply 
pipe 2200. A sealing pin 602 is inserted into the ink pipe 1600 in order 
to establish a capillary action between the fixed end of the ink pipe 1600 
and the ink supply pipe 2200. A free end of the ink pipe 1600 is joined to 
the ink inlet 1500 with pressure force. Reference numeral 601 denotes a 
packing material for sealing a joint portion between the ink tank IT and 
the in supply pipe 2200. Reference numeral 700 denotes a filter placed at 
the end portion of the ink supply pipe 2200 on the side of the ink tank 
IT. 
As the ink supply member 600 is made by a molding method, the supply member 
600 is attained a low cost and is finished with correct dimensions in the 
molding process practically. Further, in the ink supply member 600, owing 
to the cantilever structure of the ink pipe 1600, it is possible to keep 
the stable state of pressure welding the ink pipe 1600 onto the ink inlet 
1500 in mass production planning. In this embodiment, under the state of 
pressure welding the ink pipe 1600 onto the ink inlet 1500, only by 
pouring a sealing bond into the side of the ink inlet 1500 from the side 
of the ink supply member 600, it is possible to establish a perfect ink 
flow path without leakage. The method for fixing the ink supply member 600 
to the support member 300 is described as in the following steps; (1) 
putting pins (not shown) at the rear side of the ink supply member 600 
into holes 1901, 1902 at the support member 300 and push out the pins 
through the holes 1901, 1902 at the other face of the support member 300, 
and (2) bonding the end portion of the pins onto the rear face of the 
support member 300 by heat fusion method. The end projection of the pins 
bonded is held in a relevant concave portion (not shown in drawings) on 
the side surface of the ink tank IT where the recording head unit IJU is 
mounted, and then a location of the recording head unit IJU is fixed 
correctly with the ink tank IT. 
(ii) The structure of the ink tank IT 
The ink tank IT is composed of a body of cartridge 1000, an ink absorber 
900 and a cover plate 1100. The cover plate 1100 is used as to seal the 
ink absorber 900 after inserting the ink absorber 900 into the body of 
cartridge 1000 from an opening on the opposite side of the face where the 
recording head unit IJU is mounted in the body of cartridge 1000. 
The ink absorber 900 is used for absorbing ink and placed in the body of 
cartridge 1000. Reference numeral 1220 denotes an ink supply outlet for 
supplying ink to the recording head unit IJU comprising the above 
mentioned components 100 through 600. In addition, the outlet 1220 is also 
used as to be an inlet port for pouring ink into the absorber 900 by an 
ink pouring process prior to mounting the recording head unit IJU on the 
body of cartridge 1000. 
In this embodiment, ink can be supplied into the ink tank IT through either 
an atmospheric air communication port 1401 or this ink supply outlet 1220. 
However, for the purpose of pouring ink into the absorber 900 relatively 
efficiently and uniformly, it is preferable to pour ink through the ink 
supply outlet 1220. This is because the empty space only containing air in 
the ink tank IT, which is formed by ribs 2300 in the body of cartridge 
1000 and partial ribs 2400 and 2500 of the cover plate 1100 in order to 
attain an efficient ink supply flow from the absorber 900, occupies a 
corner space communicating with the atmospheric air communication port 
1401 and positioning at a longest distant from the ink supply outlet 1220. 
The body of cartridge 1000 comprises four ribs 2300, 2300, 2300, 2300 
(only two ribs are shown in FIG. 8) parallel to the moving line of the 
carriage HC. The ribs 2300, 2300, 2300, 2300 are arranged on the back end 
of the inner surface of the body of cartridge 1000 so that the rib 2300 
prevents the absorber 900 from contacting to the back end of the inner 
surface of the body 1000 of the ink tank. The partial ribs 2400 and 2500 
are also placed on the inner surface of the cover plate 1100 positioned on 
the extension line from the ribs 2300, 2300, 2300, 2300. In contrast with 
the rib 2300, the partial ribs 2400 and 2500 are composed of many smaller 
pieces of ribs respectively so that a volume of empty space containing air 
of the ribs 2400 and 2500 becomes larger than the ribs 2300, 2300, 2300, 
2300. The partial ribs 2400 and 2500 are distributed over half or less of 
the area of the inner face of the cover plate 1100. With these ribs, the 
flow of ink from the corners of the ink tank IT far from the ink supply 
outlet 1220 to the ink supply outlet 1220 is stabilized, so that the ink 
can be lead from every region of the absorber 900 into the ink supply 
outlet 1220 by a capillary action. The atmospheric air communication port 
1401 is an open hole on the cover plate for communicating air between the 
inner containment of the ink tank IT and the atmosphere. The atmospheric 
air communication port 1401 is plugged with an ink repellant material 1400 
for preventing ink leakage. 
A space of ink containment of the ink tank IT in this embodiment is a 
rectangular parallelepiped piped and a longer side of the space is 
corresponding to the side of the ink tank IT as shown in FIG. 8 and FIG. 
9. Hence, the layout described above are effective specifically in this 
case. In case that the ink tank IT has its longer side in the direction of 
the movement of the carriage HC or the ink tank IT has the inner 
containment space in a cube, the flow of ink in the absorber 900 can be 
stabilized by placing those ribs on the whole area of the inner face of 
the cover plate 1100. 
A rectangular ink reservoir (ink tank) is preferable to contain ink as much 
as possible in a limited space. With such ink reservoir, it is effective 
to provide ribs 2300, 2400 and 2500 that can achieve the above effect at 
two areas near the corners of the ink tank IT to use ink stored in the ink 
tank IT without waste. In addition, the ribs 2300, 2400, 2500 inside the 
ink tank IT of the present embodiment are nearly uniformly disposed in the 
thickness direction (the vertical direction in FIG. 8) of a rectangular 
ink absorber 900. This arrangement is important because the ribs form 
space between the ceiling plate (the cover plate 1100, the body of 
cartridge 1000) of the ink tank IT and the absorber 900, and the space 
enables atmospheric pressure to be applied uniformly on the ink retained 
in the absorber 900 so that the ink in the absorber 900 can be used up 
leaving a least amount of waste ink. 
The technological conception of the positioning of the ribs will be more 
specifically described. The position of the ribs must be determined so 
that they are placed at the diagonal corner 900a of the absorber 900 with 
regard to the ink supply outlet 1220 because the ink in this corner is 
liable to remain there. In other words, the diagonal corner 900a exists 
out the circular arc with its center at the ink supply outlet 1220 and 
with radius of the length of longer side of the ink tank IT, and with such 
positioning of the ribs, atmospheric pressure rapidly applies on diagonal 
corner 900a. The atmospheric air communicating port 1401 is not restricted 
to the position of the embodiment as long as it can guide the air into the 
area at which the ribs are disposed. 
In addition, in this embodiment, the rear surface of the recording head 
cartridge IJC is made plane so that the space required to mount the 
cartridge IJC on the apparatus is minimized, or the ink amount contained 
in maximized. As a result, the size of the apparatus is made smaller, and 
the exchange frequency of the cartridge IJC can be reduced. 
Furthermore, projected portion 1000a for providing the atmospheric air 
communicating port 1401 is formed utilizing the back portion of the space 
for unifying the recording head unit IJU to the ink tank IT. Inside the 
projected portion 1000a, a hollow is formed in which a space 1402 for 
applying atmospheric pressure to the absorber 900 in the vertical 
direction is provided. The space 1402 for applying atmospheric pressure is 
a comparatively large space, in the upper side of which the atmospheric 
air communicating port 1401 is provided. This makes it possible to 
temporarily hold the leaked ink in the case where the ink accidentally 
leaks from the absorber 900, and to positively retrieve it into the 
absorber 900. 
A structure of the mounting face of the ink tank IT to which the recording 
head unit IJU is mounted is illustrated in the FIG. 10. When a line L1 is 
taken to be a straight line passing through the center of the ink ejection 
outlet of the orifice plate 400 and parallel to the bottom face of the ink 
tank IT or to the reference face on the surface of the carriage HC, two 
protruding portions 1012, 1012 to be inserted into the hole 312 of the 
support member 300 are on the line L1. The height of the protruding 
portions 1012, 1012 is a little less than the thickness of the support 
member 300 and the support member 300 is positioned with the protruding 
portions 1012, 1012. On the extension of the line L1, as shown in FIG. 10, 
a click 2100 is formed for catching a right angular hook surface 4002 of a 
locating hook 4001 which is formed on the carriage HC as shown in FIG. 11, 
so that a force for locating the recording head cartridge IJC to the 
carriage HC is applied in parallel to the before mentioned reference face 
on the surface of the carriage HC including the line L1. This layout 
relationship forms an effective structure to make the accuracy of locating 
the recording head cartridge IJC to the carriage HC to be equivalent to 
that of locating the ink ejection outlet of the ink jet head IJH. 
In addition, the length of the protruding portions 1800 and 1801 to be 
inserted in the holes 1900 and 2000 for fixing the support member 300 onto 
the side wall of the ink tank IT is greater than that of the above 
mentioned protruding portions 1012. The portions 1800 and 1801 are used 
for fixing the support member 300 on the side wall of the ink tank IT by 
penetrating through the holes 1900, 2000 of the support member 300 and by 
bonding the end part of the protruding portions 1800 and 1801 to the 
support member 300 with a heat fusion method. Let L3 be a straight line 
intersecting perpendicularly with the straight line L1 and passing the 
protruding portion 1800, and let L2 a straight line intersecting 
perpendicularly with the straight line L1 and passing the protruding 
portion 1801. The center of the before mentioned ink supply outlet 1220 is 
located nearly on the straight line L3 so that the protruding portion 1800 
works for stabilizing the connection state between the ink supply outlet 
1220 and the ink supply pipe 2200 so as to make it possible to reduce the 
over load on this connection state in case of dropping them and/or giving 
them shocks. As the straight lines L2 and L3 do not intersect at any point 
each other and there are protruding portions 1800 and 1801 in the 
neighborhood of the protruding portion 1012 at the side of the ink 
ejection outlet of the recording head IJH, a supportive effect occurs for 
locating the recording head unit IJU on the ink tank IT. And a curve L4 
illustrated in FIG. 7 shows a position of an outside wall of the ink 
supply member 600 when installed. As the protruding portions 1800 and 1801 
are disposed out along the curve L4, it is possible that the ink tank IT 
stably supports the recording head unit IJU with enough high strength and 
dimensional accuracy under the application of the weight load of the 
recording head unit IJU. When the recording head cartridge IJC is mounted 
on the carriage HC, a nose flange 2700 of the ink tank IT is inserted into 
a hole in a front plate 4000 of the carriage HC (shown in FIG. 11) so as 
to prevent an abnormal state where the displacement of the recording head 
cartridge IJC becomes extremely large. 
Reference numeral 2101 designates a stop for preventing the cartridge IJC 
from slipping off the carriage HC, and is placed corresponding to a bar 
(not shown) of the carriage HC. With this arrangement, when the cartridge 
IJC is mounted by being turned on the carriage HC, the stop 2101 enters 
into a lower side of the bar so that the cartridge IJC maintains its 
position even if such an accidental upward force as separating the 
cartridge IJC from its normal mounting position acts on the cartridge IJC. 
The recording head unit IJU is installed inside of the cartridge IJC and 
then is closed with the cover plate 800 so that the recording head unit 
IJU is surrounded by the cartridge IJC and the cover plate 800 except an 
underside of the cartridge IJC. However, this underside opening is close 
to a mounting surface of the carriage HC when the recording head cartridge 
IJC is mounted on the carriage HC, thereby a substantially perfectly 
closed space around the recording head unit IJU is established. 
Accordingly, though the heat generated from the recording head IJH within 
the closed space is valid as forming a heat jacket, during a long time of 
a continuous ink ejection, the temperature of the closed space increases 
slightly. In this embodiment, for promoting a natural heat dissipation 
from the supporting member 300, a slit 1700 with a width less than that of 
the above-mentioned closed space is formed on the upper deck of the 
recording head cartridge IJC as shown in FIGS. 8, 9 and 10. Owing to the 
slit 1700, it is possible to prevent the temperature rise within the 
closed space and to establish an uniform temperature distribution in the 
whole of the recording head unit IJU being independent of any 
environmental fluctuation. 
By assembling the recording head cartridge IJC composed of the ink tank IT 
and the recording head unit IJU as shown in FIG. 9, ink can be fed from 
the ink tank IT into the ink supply member 600 thorough the ink outlet 
1220, the hole 320 of the supporting member 300 and a inlet provided on a 
back face of the ink supply member 600, and after ink flows inside the ink 
supply member 600, ink pours into the common in chamber through an 
adequate ink supply tube and the ink inlet 1500 of the top plate 1300 from 
the ink outlet of the ink supply member 600. Gaps formed at connecting 
portions of these components for supplying ink described above are filled 
with packing substance such as a silicone rubber, a butyl rubber or the 
like for sealing the gaps, and then an ink feed route is established. 
In this embodiment, a material used for the top plate 1300 is an 
ink-resistant synthetic resin such as polysulfone, polyether sulphone, 
polyphenylene oxide, polypropylene or the like. The top plate 1300 is 
molded into a single module together with the orifice plate 400. 
As described above, as the ink supply member 600, the single module of the 
top plate 1300 with the orifice plate 400, and the body 1000 of the ink 
tank IT are a single module molded respectively, not only a high accuracy 
in assembling the components for ejecting ink can be attained but also a 
quality of the components in a mass production is increased effectively. 
In addition, by assembling individual parts into a single molded 
component, the number of parts of the recording head cartridge IJC may be 
reduced, compared with a conventional assembling method. 
In this embodiment, a slit S (as shown in FIG. 9) and another slit (not 
shown) similar to the slit S are provided above the under the ink supply 
member 600: as shown in FIGS. 8-9, the slit S is formed between the top 
surface 603 of the ink supply member 600 and the front portion 4008 of the 
ceiling surface of the ink tank IT which is provided with a slit 1700; and 
the other slit is formed between the bottom surface 604 of the ink supply 
member 600 and a head side portion 4011 of a thin plate member to which a 
cover plate 800 of the ink tank IT is joined with adhesive bonding. These 
slits between the ink tank IT and the ink supply member 600 not only serve 
to enhance the heat dissipation from the slit 1700, but also prevent undue 
forces applied to the ink tank IT from directly acting on the supply 
member 600 or the recording head unit IJU. 
(iii) An installation of the recording head cartridge IJC onto the carriage 
HC 
In FIG. 11, reference numeral 5000 denotes a platen roller for guiding a 
recording medium P such as a sheet of paper moving in the direction from a 
back side of the drawing paper of FIG. 11 to a front side. The carriage HC 
moves along the platen roller 5000. The carriage HC has, in a forward area 
of the carriage HC facing to the platen roller 5000, the front plate 4000 
(with a thickness of 2 mm) in front of the recording head carriage IJC and 
has, at the left said of the middle area in the carriage HC, a support 
board 4003 which is erected perpendicularly to the surface of the carriage 
HC. The support board 4003 supports a flexible sheet 4005 furnished with 
pads 2011 corresponding to pads 1201 on the distributing substrate 1200 of 
the recording head cartridge IJC, and a rubber pad 4006 for generating 
elastic force for pressing the reverse side of the flexible sheet 4005 
onto the pads 2011. In addition, the carriage HC has the locating hook 
4001 for holding the recording head cartridge IJC. The front plate 4000 
has two locating protruding surfaces 4010, 4010 corresponding to the 
before mentioned locating protrusions 2500 and 2600 of the support member 
300. The locating protruding surfaces 4010, 4010 receive a vertical 
pressure when the recording head cartridge IJC is installed in the 
carriage HC. The front plate 4000 has, on the side of the platen roller 
5000, a plurality of reinforcing ribs (not shown in drawings) elongating 
in the direction opposing to the vertical pressure. The surface of these 
ribs is a little closer by about 0.1 mm to the platen roller 5000 than the 
position of front surface L5 (shown in FIG. 11) of the recording head 
cartridge IJC and hence these ribs are used also for protecting the 
recording head IJH from the recording medium or the like. The support 
board 4002 for electrical connection has a plurality of reinforcing ribs 
4004 elongating in the vertical direction to the elongating direction of 
the above-mentioned reinforcing ribs of the front plate 4000. An amount of 
the protrusion of the ribs 4004 is gradually reduced along the direction 
from the platen roller 5000 side to the hook 4001. This configuration of 
the ribs 4004 also enables the recording head cartridge IJC to be 
positioned with an inclination angle to the plate roller 5000 as shown in 
FIG. 11. The support board 4003 applies force to the distributing 
substrate 1200 of the recording head cartridge IJC so as to stabilize 
electrical connection, that is, two locating surfaces 4007, 4007 are 
formed on the support board 4003. The locating surfaces 4007, 4007 between 
which a pad contact region is defined limit the distortion length of the 
rubber pad sheet 4006 corresponding to pad 2011. Once the recording head 
cartridge IJC is mounted in the right position, the locating surfaces 
4007, 4007 contact on the surface of the distributing substrate 1200. 
Moreover, in this embodiment, as pads 1201 of the distributing substrate 
1200 is arranged on symmetrical with respect to the before mentioned 
straight line L1 (shown in FIG. 10), the distortion amount of the pads on 
the rubber pad sheet 4006 is made to be uniform and then a contacting 
pressure between the pads 2011 and 1201 is more stabilized. In this 
embodiment, the pads 1201 are arranged in an array with 2 center rows, 2 
upper columns and 2 under columns as shown in FIG. 8. 
The locating hook 4001 has a slot engaging an fixing axis 4009 of carriage 
HC. Using a movable space defined in the slot, by rotating the locating 
hook 4001 counterclockwise from the position shown in the FIG. 11 and 
moving the locating hook 4001 left in a parallel line to the platen roller 
5000, the location of the recording head cartridge IJC can be mounted on 
the carriage HC. Though any means for moving the locating hook 4001 may be 
used, a moving mechanism with a lever or the like is suitable for moving 
the locating hook 4001. The following is a further detailed and stepwise 
description about mounting the recording head cartridge IJC on the 
carriage HC. (1) At first, in response to the rotating movement of the 
locating hook 4001, the recording head cartridge IJC moves to the side of 
the platen roller 5000 and at the same time the locating protrusions 2500 
and 2600 move to the position where they can contact the locating 
protruding surfaces 4010, 4010 of the front plate 4000. (2) Next, by the 
movement of the locating hook 4001 in the left direction, a rectangular 
surface of the hook surface 4002 well contacts a rectangular surface of 
the click 2100 of cartridge IJC and at the same time the locating hook 
4001 rotates horizontally around the contacting of the locating components 
2500 and 4010, and then as a result the pads 1201 and 2011 begin to 
contact closely to each other. (3) The locating hook 4001 is held in a 
fixed position, thereby a perfect contacting state between the pads 1201 
and 2011, a perfect contacting state between the locating protrusions 2500 
and 4010, a facial contacting state between the rectangular surface of the 
hook surface 4002 and the click 2100 and a face contacting state between 
the distributing substrate 1200 and the locating surfaces 4007, 4007 of 
the support board 4003 are established at the same time, and then the 
mounting of the recording head cartridge on the carriage HC is established 
finally. 
(iv) The ink jet recording apparatus 
FIG. 12 illustrates schematically perspective view of an ink jet recording 
apparatus IJRA using the recording head cartridge IJC described above. A 
lead screw 5004 is rotated reversibly by the torque transmitted through 
driving gears 5011, 5010 and 5009 from a driving motor 5013. As the 
driving motor 5013 rotates clockwise or counterclockwise, simultaneously 
the lead screw 5004 rotates in the same manner. A pin arranged in the 
carriage HC meshes with a lead groove 5005 so that the carriage HC moves 
in the either direction of the arrow a or b as shown in FIG. 12 as the 
lead screw 5004 rotates clockwise or counterclockwise. Reference numeral 
5002 denotes a paper pressure plate. The paper pressure plate 5002 presses 
the recording medium P over a range along the moving direction of the 
carriage HC against the platen roller 5000. Reference numerals 5007 and 
5008 denote photo-couplers, which generate a signal for sensing an 
existence of a lever 5006 in the region where photo-couplers are placed. 
The signal is used to change the turning direction of the motor 5013 at a 
home position and so on. Reference numeral 5016 denotes a supporting 
member for support a cap 5022 which is used to cap the front side of the 
recording head IJH. Reference numeral 5015 denotes a sucking makes an 
inside of the cap 5022 to be negative pressure so that the ink is absorbed 
from the ejection outlets of the recording head, that is, the sucking unit 
5015 absorbs ink through an aperture 5023 within the cap 5022. Reference 
numeral 5017 denotes a cleaning blade. Reference numeral 5019 denotes a 
member for enabling the cleaning blade 5017 to move forward or backward. 
The cleaning blade 5017 and the member 5019 are supported by a supporting 
plate 5018. As for another embodiment of the cleaning blade 5017, need 
less to say another other types of cleaning blades as used in the prior 
art, are applicable to the present embodiment. In addition, a lever 5021 
used for starting an absorbing procedures by the sucking unit 5015. The 
lever 5021 moves in accordance with the movement of a cam 5020 which can 
engages the carriage HC so that a driving force from the driving motor 
5013 is transmitted to the sucking unit 5015 through transmission 
mechanism as used in prior art such as means for switching a clutch. These 
capping, cleaning and absorption restoration operations are respectively 
performed in accordance with the movement of the carriage HC to the home 
position, that is, the operations are performed at their right positions 
in accordance with the rotation of the lead screw 5004. However, so long 
as an arrangement for the above mentioned operations is that the 
operations are performed at an appropriate timing, such arrangement may be 
applied to the apparatus of this embodiment. 
Incidentally, the leaf spring 500 (shown in FIG. 8) is used to mechanically 
press join the substrate (heater board) 100 and the top plate 1300 to form 
the ink passages and the common liquid chamber as described above, and is 
made, for example, from phosphor bronze, stainless steel for springs, FRP, 
or the like. Adhesives are used for temporarily fixing the substrate 100 
and the top plate 1300 with grooves: in practice, a photo-setting type 
adhesive is used. 
The leaf spring 500 has an M-shaped form which has a spring portion 
(vertical portion in FIG. 8) near parallel with the top surface of the top 
plate 1300, and side portions along the sides of the substrate 100 and the 
top plate 1300. The side portions have nails at the ends thereof that 
engage the supporting plate 300 to produce pressure of the leaf spring 
500. In addition, the plate spring 500 has a projection 501 that protrudes 
at the side of spring portion thereof, and is turned perpendicularly to 
that portion toward the top of the top plate 1300. The projection 501 
press joins the substrate 100 and the top plate 1300 by means of line 
pressure so as to concentrate the stress produced by the leaf spring 500, 
thereby obtaining uniform pressure applied to the substrate and the top 
plate. 
Although it is preferable that the joining member like the leaf spring 500 
is provided with members like the projection 501, the projection 501 is 
not essential to achieve the bubble moving effect through the gaps between 
the adjacent ink passages. Such a leak spring provides uniform joint force 
on the vicinity of ejection outlets and on the entire areas of the ink 
passages at which reliable joint is required because the leaf spring 
presses the top plate downward and the pressure is distributed. On the 
other hand, the leaf spring presents only weak joint force on the 
peripheries of the ink passages. Thus, the leaf spring is suitable for 
producing the above-mentioned gaps in the channel walls separating the ink 
passages. 
As a material of the flat spring 500, the present embodiment uses phosphor 
bronze, thereby producing force of 1 kg with thickness of 0.15 mm. The 
projection 501 functioning as line pressure generating portion is provided 
on the leaf spring 500. With this arrangement, the pressure can be 
uniformly applied to the areas where ink passages are formed and to the 
vicinity of the ejection outlets along the entire region in which the 
ejection outlets are disposed. Thus, the channel walls between the 
adjacent ink passages are positively formed. This will increase the 
relative pressure difference along the extending direction of the ink 
passages, and hence the oscillation of the top plate or the like caused by 
the pressure waves in the ink associated with the ink ejection can be 
concentrated at the region from the back of the electro-thermal converting 
elements to the common liquid chamber. As a result, increasing effect can 
be achieved to remove bubbles sticking to the inner walls, and to remove 
bubbles via the gaps. 
Incidentally, as describe above, the ejection recovery procedures of the 
foregoing embodiment of the present invention are effective for recording 
heads having the common liquid chamber and the plurality of ink passages 
communicating thereto. The arrangement of the ink passages with regard to 
the common liquid chamber is not restricted to the manner described above. 
For example, a multiple layer arrangement of ink passages can be adopted 
wherein passages, and all the ink passages communicate to the common ink 
chamber. In this case, bubbles in the ink passages can be expelled by 
ejecting ink from the surrounding ink passages, namely, from top, bottom, 
left hand right hand ink passages of that ink passage. 
Furthermore, the ejecting ink can be directed in any direction: it can face 
upward, downward, sideward, or any other directions. 
Furthermore, in the foregoing embodiments, expelling procedure of remaining 
bubbles in the recording head is described exemplifying the recording head 
in which ink is ejected by the bubble generated in the ink by thermal 
energy. The present invention, however, can be applied to recording heads 
adopting ejection system which uses ejection energy elements such as 
piezoelectric elements for producing pressure waves in the ink. 
Further, this specification discloses that the bubble expelling procedures 
where the ink ejection is carried out from the orifices connected to the 
ink passages which include at least the ink passage adjacent to the ink 
passage that contains a bubble to be expelled, but which exclude the ink 
passage that contains the bubble to be expelled so that pressure 
fluctuations in ink or ink flows occur to thereby expel the bubble. 
Therefore, it is not necessary that the recording head in which the bubble 
expelling procedures described above can be carried out has the structure 
described above. 
As is clear from the above description, the present invention is 
characterized in that it does not eject ink from the very orifices from 
which the remaining bubbles are to be expelled, but ejects ink from other 
orifices at least including orifices adjacent to those orifices from which 
the remaining bubbles are to be expelled in the case where bubbles 
remaining in the ink passages are expelled in the recording head. Thus, 
the remaining bubbles are expelled from the aimed orifices. In this point, 
the present invention differs from the conventional ejection recovery 
procedure which is known as an idle ejection. An example of the 
conventional ejection recovery method is disclosed in Japanese Patent 
Application Laying-open No. 2-194967. With this method, comparatively 
small remaining bubbles, or ink of increased viscosity is discharged by 
ejecting ink from the orifice from which the small remaining bubbles or 
the ink of increased viscosity are to be expelled. It is difficult for the 
idle ejection, however, to expel remaining bubbles that have grown to 
comparatively large sizes. 
The present invention is particularly suitably useable in an ink jet 
recording head having thermal energy means for producing thermal energy as 
energy used for ink ejection such as a plurality of electro-thermal 
transducers, a laser apparatus for generating a plurality of laser beams 
or the like and a recording apparatus using the head. The thermal energies 
cause variation of ink condition thereby eject ink. This is because a high 
density of the picture element and a high resolution of the recording are 
possible. 
The typical structure and the operational principle are preferably the one 
disclosed in U.S. Pat. Nos. 4,723,129 and 4,740,796. The principle is 
applicable to a so-called on-demand type recording system; and a 
continuous type recording system particularly, however, it is suitable for 
the on-demand type because the principle is such that at least one driving 
signal is applied to an electro-thermal transducer disposed on liquid 
(ink) retaining sheet or ink passage, the driving signal being enough to 
provide such a quick temperature rise beyond a departure from nucleation 
boiling point, by which the thermal energy is provide by the 
electro-thermal transducer to produce film boiling on the heating portion 
of the recording head, whereby a bubble can be formed in the liquid (ink) 
corresponding to each of the driving signals. By the development and 
collapse of the bubble, the liquid (ink) is ejected through an ejection 
outlet to produce at least one droplet. The driving signal is preferably 
in the form of a pulse, because the development and collapse of the bubble 
can be effected instantaneously, and therefore, the liquid (ink) is 
ejected with quick response. The driving signal in the form of the pulse 
is preferably such as disclosed in U.S. Pat. Nos. 4,463,359 and 
4,345,262. In addition, the temperature increasing rate of the heating 
surface is preferably such as disclosed in U.S. Pat. No. 4,313,124. 
The structure of the recording head may be as shown in U.S. Pat. Nos. 
4,558,333 and 4,459,600 wherein the heating portion is disposed at a bent 
portion in addition to the structure of the combination of the ejection 
outlet, liquid passage and the electro-thermal transducer as disclosed in 
the above-mentioned patents. In addition, the present invention is 
applicable to the structure disclosed in Japanese laid-open Patent 
Application No. 123670/1984 wherein a common slit is used as the ejection 
outlet for plurality electro-thermal transducers, and to the structure 
disclosed in Japanese Patent Application Laying-open No. 138461/1984 
wherein an opening for absorbing pressure wave of the thermal energy is 
formed corresponding to the ejecting portion. This is because, the present 
invention is effective to perform the recording operation with certainty 
and at high efficiency irrespective of the type of the recording head. 
The present invention is effectively applicable to a so-called full-line 
type recording head having a length corresponding to the maximum recording 
width. Such a recording head may comprise a single recording head and a 
plurality recording head combined to cover the entire width. 
In addition, the present invention is applicable to a serial type recording 
head wherein the recording head is fixed on the main assembly, to a 
replaceable chip type recording head which is connected electrically with 
the main apparatus and can be supplied with the ink by being mounted in 
the main assembly, or to a cartridge type recording head having an 
integral ink container. 
The provision of the recovery means and the auxiliary means for the 
preliminary operation are preferable, because they can further stabilize 
the effect of the present invention. As for such means, there are capping 
means for the recording head, cleaning means therefor, pressing or sucking 
means, preliminary heating means by the ejection electro-thermal 
transducer or by a combination of the ejection electro-thermal transducer 
and additional heating element and means for preliminary ejection not for 
the recording operation, which can stabilize the recording operation. 
As regards the kinds and the number of the recording heads mounted, a 
single head corresponding to a single color ink may be equipped, or a 
plurality of heads corresponding respectively to a plurality of ink 
materials having different recording color or density may be equipped. The 
present invention is effectively applicable to an apparatus having at 
least one of a monochromatic mode solely with main color such as black and 
a multi-color mode with different color ink materials or a full-color mode 
by color mixture. The multi-color or full-color mode may be realized by a 
single recording head unit having a plurality of heads formed integrally 
or by a combination of a plurality of recording heads. 
Furthermore, in the foregoing embodiment, the ink has been liquid. It may, 
however, be an ink material solidified at the room temperature or below 
and liquefied at the room temperature. Since in the ink jet recording 
system, the ink is controlled within the temperature not less than 
30.degree. C. and not more than 70.degree. C. to stabilize the viscosity 
of the ink to provide the stabilized ejection, in usual recording 
apparatus of this type, the ink is such that it is liquid within the 
temperature range when the recording signal is applied. In addition, the 
temperature rise due to the thermal energy is positively prevented by 
consuming it for the state change of the ink from the solid state to the 
liquid state, or the ink material is solidified when it is left is used to 
prevent the evaporation of the ink. In either of the cases, the 
application of the recording signal producing thermal energy, the ink may 
be liquefied, and the liquefied ink may be ejected. The ink may start to 
be solidified at the time when it reaches the recording material. The 
present invention is applicable to such as ink material as is liquefied by 
the application of the thermal energy. Such an ink material may be 
retained as a liquid or solid material on through holes or recesses formed 
in a porous sheet as disclosed in Japanese laid-open Patent Application 
No. 56847/1979 and Japanese laid-open Patent Application No. 71260/1985. 
The sheet is faced to the electro-thermal transducers. The most effective 
one for the ink materials described above is the film boiling system. 
The ink jet recording apparatus may be used as an output means of various 
types of information processing apparatus such as a work station, personal 
or host computer, a word processor, a copying apparatus combined with an 
image reader, a facsimile machine having functions for transmitting and 
receiving information, or an optical disc apparatus for recording and/or 
reproducing information into and/or from an optical disc. These apparatus 
requires means for outputting processed information in the form of hand 
copy. 
FIG. 13 schematically illustrates one embodiment of a utilizing apparatus 
in accordance with the present invention to which the ink jet recording 
apparatuses shown in FIG. 3, 6 and 12 are equipped as an output means for 
outputting processed information. 
In FIG. 13, reference numeral 1000 schematically denotes a utilizing 
apparatus which can be a work station, a personal or host computer, a word 
processor, a copying machine, a facsimile machine or an optical disc 
apparatus. Reference numeral 11000 denotes the ink jet recording 
apparatuses (IJRA) shown in FIGS. 3, 6 and 12. The ink jet recording 
apparatuses (IJRA) 11000 received processed information from the utilizing 
apparatus 10000 and provides a print output as hand copy under the control 
of the utilizing apparatus 10000. 
FIG. 14 schematically illustrates another embodiment of a portable printer 
in accordance with the present invention to which a utilizing apparatus 
such as a work station, a personal or host computer, a word processor, a 
copying machine, a facsimile machine or an optical disc apparatus can be 
coupled. 
In FIG. 14, reference numeral 10001 schematically denotes such a utilizing 
apparatus. Reference numeral 12000 schematically denotes a portable 
printer having the ink jet recording apparatuses (IJRA) 11000 shown in 
FIGS. 3, 6 and 12 are incorporated thereinto and interface circuits 13000 
and 14000 receiving information processed by the utilizing apparatus 11001 
and various controlling data for controlling the ink jet recording 
apparatus 11000, including hand shake and interruption control from the 
utilizing apparatus 11001. Such control per se is realized by conventional 
printer control technology. 
Although specific embodiments of a record apparatus constructed in 
accordance with the present invention have been disclosed, it is not 
intended that the invention be restricted to either the specific 
configurations or the uses disclosed herein. Modifications may be made in 
a manner obvious to those skilled in the art. 
For example, although the embodiments are described with regard to a serial 
printer, the present invention can also be applied to line printers. Here, 
the serial printer is defined as a printer that has a moving member on 
which the record head is mounted, the moving member being moved to and 
from in the direction perpendicular to the transporting direction of the 
recording paper. Accordingly, it is intended that the invention be limited 
only by the scope of the appended claims. 
The invention has been described in detail with respect to preferred 
embodiments, and it will now be apparent from the foregoing to those 
skilled in the art that changes and modifications may be made without 
departing from the invention in its broader aspects, and it is the 
invention, therefore, in the appended claims to cover all such changes and 
modifications as fall within the true spirit of the invention.