JP3493978B2 - Liquid jet recording device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of energy generating elements that generate energy for ejecting a liquid, and a plurality of individual liquid channels and liquids that are liquid passages corresponding to the energy generating elements. The present invention relates to a liquid jet recording apparatus in which a plurality of ejection ports for ejecting are provided in a recording head.

[0002]

2. Description of the Related Art Conventionally, as a typical liquid jet recording apparatus, a thermal type liquid jet recording apparatus in which a heater disposed in a liquid flow path is energized to vaporize the liquid and the pressure thereof ejects the liquid from an ejection port Are known. Figure 10
FIG. 3 is a sectional view showing an example of a thermal type liquid jet recording apparatus. In the figure, 1 is a heater substrate, 2 is a channel substrate, 3
Is a discharge port, 4 is an individual liquid channel, 5 is a common liquid chamber, 6 is a pit layer, 7 is a heating element, and 8 is a bypass section. A heating element 7 is formed as an energy generating element on the heater substrate 1, and a pit layer 6 is formed on the heating element 7 and the bypass portion 8. Further, an individual liquid flow path 4 and a common liquid chamber 5 corresponding to each heating element 7 are formed on the channel substrate 2 and are joined to the heater substrate 1. The open end of the individual liquid channel 4 serves as the ejection port 3.

The liquid is first supplied to the common liquid chamber 5 and then to the individual liquid flow paths 4 through the bypass section 8. When a drive pulse is applied to the heat generating element 7 from a drive circuit (not shown), the heat generating element 7 generates heat and the liquid in the individual liquid flow path 4 is heated to generate bubbles and grow. By the pressure at the time of bubble growth, the liquid in the individual liquid flow path 4 is discharged from the discharge port 3 as a droplet, and recording is performed.

In such a thermal type liquid jet recording apparatus, when a large number of ejection ports are arranged and lengthened to increase the printing speed, the amount of heat generated in the recording head increases and the recording head Heat storage becomes a problem. Generally, in a thermal type liquid ejecting recording apparatus, the temperature range of the recording head where stable ejection can be obtained is limited because the characteristics of the ejected liquid change depending on the temperature.

Here, a problem in liquid ejection when the recording head is at high temperature will be considered. As a method of controlling the ejection stability in a thermal type recording head, there are many proposals regarding the structural parameters of the individual liquid flow paths. For example, in the liquid jet recording apparatus as shown in FIG. 10 described above, the relationship between the volume of the individual liquid flow path from the end of the heating element 7 on the ejection port 3 side to the ejection port 3 and the volume of the ejected liquid droplets is shown. Focusing attention, there is a method of setting V _FCL −α> Vd ... Here, V _FCL is the volume from the end of the heating element 7 on the ejection port 3 side in the individual liquid flow path 4 to the ejection port 3, Vd is the volume of the ejected droplet, and α is due to the receding of the meniscus of the liquid. It is the decrease in liquid volume in V _FCL . The volume Vd of the droplet is Vb, which is the volume of the bubble formed by the heating element 7, and β is the coefficient obtained from the flow path structure parameter.
Then, Vd = β × Vb can be expressed as Equation 2 and the volume of the droplet changes depending on the flow channel structure. Therefore, the flow channel structure can be designed so as to satisfy Expression 1, and in that case, stable ejection of the droplet amount can be performed.

However, the stable droplet amount is ensured only when the recording head is designed to be used, and the volume Vb of the bubble is actually the temperature of the liquid (that is, the temperature of the recording head). ) It increases with the rise.
That is, when the temperature of the liquid (recording head) is T and a monotonically increasing function f (T) with T as a variable is used, the volume Vb of the bubble can be expressed as Vb∝f (T). .

FIG. 11 is a graph showing an example of the relationship between the temperature T of the recording head and the volume Vd of the droplet. As described above, as the temperature of the recording head increases due to printing, the bubble volume Vb increases as shown in Expression 3, and the Vd on the right side of Expression 1 increases as shown in Expression 2. Also in the recording head satisfying the condition of the formula 1 at a certain design temperature, the volume Vd of the droplet increases as the temperature of the recording head rises as shown in FIG. 11, and when the temperature of the recording head becomes a certain temperature or more, it is shown in the formula 1. If the condition is not satisfied, the stable ejection of the droplet amount cannot be performed.

As described above, in the thermal type liquid jet recording apparatus, the temperature range of the recording head in which stable jetting can be obtained is limited. Therefore, for example, Japanese Patent Laid-Open No. 11634/1993
No. 6 and Japanese Patent Laid-Open No. 7-47694 propose to avoid ejection failure by interrupting or limiting the printing operation when the recording head temperature rises too much due to heat accumulation. However, interrupting the printing operation hinders an increase in printing speed.

As an alternative method, heat dissipation is promoted,
There is also a method of providing a cooling means such as attaching a large heat sink to the recording head in order to suppress the temperature rise of the recording head. However, the installation of the cooling means leads to an increase in size of the device.

Further, many methods have been proposed in which the drive pulse applied to the heating element is changed according to the temperature of the recording head so as to suppress the increase of the volume Vd of the droplet at high temperature. For example, when the temperature of the recording head is high, it has been proposed to reduce the amount of heat generation by narrowing the drive pulse width applied to the heating element. However, a certain amount of energy is required to generate bubbles in the liquid, and the drive pulse width cannot be extremely narrowed. Therefore, there is a problem in that control for expanding the printable temperature range cannot be performed.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and can perform stable ejection even when the recording head is at a high temperature, and can respond to an increase in printing speed. An object of the present invention is to provide a liquid jet recording apparatus.

[0012]

The present invention provides an energy generating element for generating energy for ejecting a liquid,
In a liquid jet recording apparatus having a recording head provided with an individual liquid flow path which is a liquid passage corresponding to the energy generating element and a discharge port for discharging the liquid, a plurality of individual liquid flow paths for printing one pixel are provided. An individual liquid flow path is provided, and the plurality of individual liquid flow paths are formed as individual liquid flow paths of different types of structures, and head temperature detecting means for detecting the temperature of the recording head. According to the temperature of the recording head detected by the head temperature detecting means, an individual liquid flow path satisfying the following formula 1 is selected from the plurality of individual liquid flow paths and corresponds to the selected individual liquid flow path. It is characterized in that it has a driving means for driving the energy generating element. Further, according to the present invention, a recording head provided with an energy generating element that generates energy for ejecting a liquid, an individual liquid channel that is a passage of the liquid corresponding to the energy generating element, and an ejection port that ejects the liquid. In the liquid jet recording apparatus having the above, one individual liquid channel is provided as an individual liquid channel for printing one pixel, and a plurality of different types of energy generating elements are provided in the individual liquid channel. Further, the following formula 1 is satisfied from the head temperature detecting means for detecting the temperature of the recording head and the plurality of types of energy generating elements according to the temperature of the recording head detected by the head temperature detecting means. It is characterized by having a driving means for selecting and driving the energy generating element. V _FCL −α> Vd (1) where V _FCL is the volume from the discharge port side end of the energy generating element in the individual liquid flow path to the discharge port, Vd is the volume of the discharged droplet, α is the decrease in the liquid volume in V _FCL due to the receding of the liquid meniscus.

[0013]

1 is a sectional view showing a first example of a recording head in an embodiment of a liquid jet recording apparatus of the present invention, and FIG. 2 is a partial perspective view of an example of a heater substrate. is there. 10, those parts that are the same as those corresponding parts in FIG. 10 are designated by the same reference numerals, and a description thereof will be omitted. 11 is the first heating element, 12 is the second
It is a heating element of. In this example, the individual liquid channels 4 having two types of channel structures are alternately arranged. Of course, the individual liquid flow path 4 having three or more kinds of flow path structures
May be arranged.

In the individual liquid flow path 4 shown in FIG. 1A, the first heating element 11 is arranged at a position close to the ejection port 3. At this time, the volume of the individual liquid flow path 4 from the ejection port 3 to the end of the first heating element 11 on the ejection port 3 side (the cross-hatched portion in the drawing) is _defined as V _FCL 1. The area of the first heating element 11 is HS1.

Further, in the individual liquid flow path 4 shown in FIG. 1B, the second heating element 12 is arranged at a position farther from the ejection port 3 than the first heating element 11. At this time, the volume of the individual liquid flow path 4 from the discharge port 3 to the end of the second heating element 12 on the discharge port 3 side (the cross-hatched portion in the drawing) is _defined as V _FCL 2. The area of the second heating element 12 is HS2. Area H of this second heating element 12
S2 is equal to or smaller than the area HS1 of the first heating element 11,
In this example, the area is smaller than the area HS1 of the first heating element 11.

In the case of satisfying the above formula 1 and performing stable jetting of the droplets, in order to satisfy the formula 1 even when the droplet amount Vd increases with the temperature rise of the recording head, the ejection port 3 Volume of individual liquid flow path from the end to the end of the heating element V _FCL
Or to reduce the droplet volume Vd, the volume Vb of the bubble may be reduced, that is, the area HS of the heating element, which is an energy generating element, may be reduced. For example, considering the volume V _FCL of the individual liquid flow path from the discharge port 3 to the end of the heating element, the volume that satisfies the formula 1 at _low temperature T _low including room temperature is V _FCL (T _low ), and the volume satisfying formula 1 at _high temperature T _{high is} When the volume that satisfies the above is _defined as V _FCL (T _high ), if V _FCL (T _high )> V _FCL (T _low ), Equation 1 is satisfied and stable even if the droplet amount Vd increases at _high temperature T _high. It is possible to eject the formed droplets. Also,
Considering the area HS of the heat generating element, HS area of the heat generating element to meet the low temperature T _low at Formula 1, including room temperature (T
_low ), and when the area of the heating element that satisfies Equation 1 at _high temperature T _high is HS (T _high ), if HS (T _high ) <HS (T _low ), the volume Vb of the bubble becomes small at _high temperature T _high. As a result, it is possible to suppress the increase in the droplet amount Vd and to eject the droplets stably, which satisfies Expression 1.

In the two kinds of flow channel structures shown in FIG. 1, the first or second heating element 11,
The volume relationship of the individual liquid flow path 4 up to the end of 12 is V _FCL 2> V _FCL 1, and the area relationship of the first and second heating elements 11 and 12 is HS2 <HS1. That is, these two flow channel structures satisfy the above-mentioned relationship, and the structure of the individual liquid flow channel 4 shown in FIG. 1 (A) is a flow channel structure suitable for _low temperature T _low , and FIG. The structure of the individual liquid channel 4 shown is a channel structure suitable for _high temperature T _high . Then, within the range of the above conditions, FIG.
The temperature range that can be covered by the structure of the individual liquid channel 4 shown in FIG. 1 and the temperature range that can be covered by the structure of the individual liquid channel 4 shown in FIG. As a result, stable injection can be performed at both low temperature and high temperature.

FIG. 3 is a block diagram showing an embodiment of the liquid jet recording apparatus of the present invention. In the figure, 21 is a recording head, 22 is a head temperature detection unit, and 23 is a drive unit.
The recording head 21 is provided with a first heating element 11 and a second heating element 12. Head temperature detector 22
Detects the temperature of the recording head 21. The drive unit 23 is
Either the first heating element 11 or the second heating element 12 is selected according to the temperature of the recording head 21 detected by the head temperature detection unit 22. Then, according to the input print data, the drive pulse is sent to the selected heating element.

When the recording head 21 shown in FIGS. 1 and 2 is used, as described above, the first heating element 11 can perform stable ejection at a low temperature, and the second heating element 12 can be used. Can perform stable injection at high temperature. The drive unit 23 selects the first heating element 11 when the temperature of the recording head 21 detected by the head temperature detection unit 22 is low including room temperature, and outputs a drive pulse according to the print data to the first heating element 11. Send out. As a result, in the recording head 21, only the first heating element 11 generates heat according to the drive pulse, and the droplets are ejected to perform recording.

When the temperature of the recording head 21 rises as the recording progresses and exceeds a predetermined temperature, the driving unit 2
3 is switched to the second heating element 12 capable of performing stable injection at high temperature. Then, the drive pulse according to the print data is sent to the second heating element 12. As a result, in the recording head 21, only the second heating element 12 generates heat according to the drive pulse, and the droplets are ejected to perform recording. By performing such control,
It is possible to stably eject liquid droplets even in a temperature range that cannot be covered only by driving one heating element.

FIG. 4 is a graph showing an example of the relationship between the temperature of the recording head and the droplet amount in the embodiment of the liquid jet recording apparatus of the present invention. In FIG. 4, the temperature range covered by the first heating element 11 is shown as T _low , and the temperature range covered by the second heating element 12 is shown as T _high . As described above, generally, in the liquid jet recording method, the temperature and the droplet amount are proportional to each other, so that the droplet amount increases as the temperature rises. At this time, in the flow path having the second heat generating element 12, the area of the second heat generating element 12 is smaller than the area of the first heat generating element 11 as described above, and the area from the discharge port 3 to the second heat generating element 12 is reduced. The volume V _FCL 2 of the individual liquid flow path 4 up to the end 12 is larger than V _FCL 1. Therefore, as shown in FIG. 4, the maximum permissible amount and the minimum permissible amount of the droplet amount in the temperature range T _high are shifted to the larger amount of the droplet amount than in the temperature range T _low .

For example, in the case of only one kind of flow channel structure shown in FIG. 10, the temperature range of the recording head which can be covered as shown in FIG. 11 is narrow. However, according to the invention,
As shown in FIG. 4, the temperature range that can be covered is T _low + T
_{It is in the high} range, and the temperature range can be greatly expanded. Therefore, for example, high-speed printing is performed and the recording head 2
Even in a situation where heat is stored in No. 1, good and stable recording can be performed without reducing the printing speed.

When two types of heating elements are switched and used as described above, for example, in order to construct a recording head for printing the same number of dots as the conventional recording head shown in FIG.
It is necessary to double the number of heating elements. However, only half of the heating elements are used at the same time, and the drive unit 23 can be realized with a circuit configuration of the same scale as the conventional one.

FIG. 5 is an explanatory diagram of an example of a driving method of the liquid jet recording apparatus. There are two main driving methods for the driving unit 23: single pulse driving and multi-pulse driving. The single pulse driving is a driving method in which one pulse is applied to the heating resistor as shown in FIG. Further, as a more stable driving method, multi-pulse driving as shown in FIG. 5B is also used. In this multi-pulse driving, driving is performed by a plurality of pulses. Figure 5
In the example shown in (B), first, energy that does not eject the liquid is applied by the pre-pulse P1 to heat the liquid. After the pause period P2, energy for ejecting the liquid is applied by the main pulse P3 to cause the droplet to fly. As a driving method of the driving unit 23, any method may be used.

Further, when such a heating element to be used is switched, the droplet amount changes before and after the switching as shown in FIG. Therefore, the switching of the heating element is 1
It is possible to suppress the deterioration of the image quality by controlling not to perform it during the printing of the page.

When the driving unit 23 is performing multi-pulse driving, the change in the droplet amount when switching the heating elements can be reduced, and switching within one page is also possible. FIG. 6 is a graph showing another example of the relationship between the temperature of the recording head and the droplet amount in the embodiment of the liquid jet recording apparatus of the present invention. In the multi-pulse drive, the drive pulse width can be controlled in accordance with the temperature of the recording head 21 as is conventionally done. That is, by narrowing the width of the pre-pulse P1 in FIG. 5B in accordance with the temperature rise, the temperature of the liquid at the time of liquid ejection is kept substantially constant,
It suppresses the change in the droplet amount. By controlling the width of the pre-pulse P1 as described above, the average change in the droplet amount in each temperature range is reduced as shown in FIG. Further, since the change in the amount of liquid droplets when switching the heating elements is reduced, it is possible to switch the heating elements without significantly affecting the image quality.

When the width of the pre-pulse P1 is controlled, it is difficult to control the pulse width in an analog manner according to the temperature, and the pulse width is usually changed for each predetermined temperature width. Within a predetermined temperature range, the amount of droplets also increases as the temperature rises. Therefore, as shown in FIG. 6, a change in the droplet amount within each temperature range has a small step at the temperature at which the pulse width is changed. However, such a difference in droplet amount hardly affects the image quality. of course,
The timing of switching may be controlled by various methods, such as changing the pulse width of the pre-pulse P1 and switching the heating elements so as not to be performed while recording continuous images.

Further, since control is performed according to the temperature of the recording head as described above, when the low temperature and high temperature individual liquid flow paths 4 as shown in FIG. It is desirable that the two types of individual liquid flow paths 4 are alternately arranged as shown in FIG. 2 so that the temperature of the entire 21 becomes uniform. Of course, other arrangement methods are not excluded.

In the examples shown in FIGS. 1 and 2, a plurality of types of flow paths are formed in which the area and the position of the heating element are changed in each individual liquid flow path 4. However, for example, the position of the heating element is the same and heat is generated. It is also possible to provide a plurality of individual liquid channels 4 having different cross-sectional areas from the element to the individual liquid channels 4 and change the volume V _FCL from the ejection port 3 to the end of each heating element.

FIG. 7 is a sectional view showing a second example of the recording head in the embodiment of the liquid jet recording apparatus of the present invention and a partial perspective view of an example of the heater substrate. Reference numerals in the figure are the same as those in FIGS. 1 and 2. In the above-mentioned first example, an example in which one heating element is arranged in each individual liquid channel 4 is shown, but in this example, two different types of heating elements are arranged in the same individual liquid channel 4. The example provided is shown. Of course, the number of types of heating elements to be arranged may be three or more.

As shown in FIG. 7, in the individual liquid flow path 4, the first heating element 11 and the second heating element 12 are arranged in this order from the side close to the ejection port 3. First heating element 1
The first and second heating elements 12 are the driving unit 2 shown in FIG.
3 are selectively driven. The area HS1 of the first heating element 11 may be equal to or larger than the area HS2 of the second heating element 12. Especially in this example, HS1> H
An example of S2 is shown.

FIG. 8 is an explanatory diagram of the volume in the individual liquid flow passage from the end of each heating element to the ejection port in the second example of the recording head in the embodiment of the liquid jet recording apparatus of the present invention. Is. As described above, as one method for satisfying the expression 1 even when the temperature of the recording head rises and performing stable droplet ejection, the volume of the individual liquid flow path 4 from the ejection port 3 to the end of the heating element is It is sufficient to increase V _FCL . When driving the first heating element 11 close to the ejection port 3, the individual liquid flow path 4 from the ejection port 3 to the end of the first heating element 11 is driven.
Volume V _FCL 1 is the volume indicated by cross-hatching in FIG. Further, when the second heating element 12 far from the ejection port 3 is driven, the volume V _FCL 2 of the individual liquid flow path 4 from the ejection port 3 to the end of the second heating element 12 is as shown in FIG. ) Is the volume shown by cross-hatching. Here, the first heating element 11 is set to a low temperature T including room temperature.
_When the temperature is _high , it is selected and driven, and when the temperature is _high, the second heating element 12 is switched to be driven. As a result, the relationship of V _FCL 2 (when T _high )> V _FCL 1 (when T _low ) is satisfied.

As another method, in order to suppress the droplet amount Vd, the volume Vb of the bubble may be reduced, that is, the area HS of the heat generating element which is an energy generating element may be reduced. Since HS1> HS2 is set in this example as described above, the first heating element 11 is set to a low temperature T _low including room temperature.
It is possible to set HS2 (at T _high time) <HS1 (at T _low time) by selectively driving at some time and switching to the second heating element 12 at the time of _high temperature T _high and driving.

The positions and areas of the first heating element 11 and the second heating element 12 are within a temperature range that can be covered by driving the first heating element 11 and a temperature range that can be covered by driving the second heating element 12. May be designed to be continuous or partially overlapped.

The head temperature detecting section 22 of FIG. 3 detects the temperature of the recording head 21 as shown in FIG. 7 and sends it to the driving section 23. The drive unit 23 selects and drives the first heating element 11 according to the temperature of the recording head 21 detected by the head temperature detection unit 22 at a low temperature T _low including room temperature, and drives the high temperature T _high.
Sometimes, the second heating element 12 is selected and driven. By switching the heating element to be driven according to the temperature of the recording head in this manner, it becomes possible to perform stable droplet ejection over a wide temperature range as shown in FIG. 4, for example.

FIG. 9 is a partial perspective view of an example of a heater substrate showing a third example of the recording head in the embodiment of the liquid jet recording apparatus of the present invention. Reference numerals in FIG. 1 and FIG.
Is the same as. In this example, two heating elements are arranged side by side within the same width of the individual liquid channel 4. Of course, three or more heating elements may be arranged.

In this example, the end portion of the first heating element 11 on the ejection port 3 side is projected to the ejection port 3 side more than the end portion of the second heating element 12 on the ejection port 3 side. As a result, the volume V _FCL 1 of the individual liquid flow path 4 from the discharge port 3 to the end of the first heating element 11 becomes the same as the volume shown by cross-hatching in FIG. In addition, the volume V _FCL 2 of the individual liquid flow path 4 from the discharge port 3 to the end of the second heating element 12
Has a volume equivalent to that shown by cross-hatching in FIG. That is, V _FCL 2> V _FCL 1. In the example shown in FIG. 9, the first heating element 11
Area HS1 and the area HS2 of the second heating element 12 are formed so that HS2 <HS1.

Such first and second heat generating elements 1
With the configurations of 1 and 12, the first heating element 11 is used at a low temperature including room temperature, and the second heating element 12 is used at a high temperature. Can be expanded. At this time, the first and second temperature ranges should be set so that each temperature range is continuous or partially overlaps.
The heating elements 11 and 12 may be designed. A recording head as shown in FIG. 9 is used as the recording head 21 in FIG. 3, and the drive unit 23 causes the first heating element 11 or the second heating element 12 to operate in accordance with the temperature of the recording head 21 detected by the head temperature detection unit 22. By switching between and driving, it is possible to stably eject the liquid droplets over a wide temperature range.

[0039]

As is apparent from the above description, according to the present invention, the energy generating element corresponding to the selected individual liquid flow path is selected by selecting the individual liquid flow path to be used according to the temperature of the recording head. By driving or driving different energy generating elements formed in the same individual liquid flow path by switching according to the temperature of the recording head, it is possible to always obtain appropriate droplet ejection in a wide temperature range and even at high temperatures. It is possible to provide a liquid jet recording apparatus that can perform stable jetting. As a result, stable image quality can be maintained even when heat is accumulated in the recording head, which has the effect of significantly increasing the printing speed.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first example of a recording head in an embodiment of a liquid jet recording apparatus of the present invention.

FIG. 2 is a partial perspective view of an example of a heater substrate showing a first example of the recording head in the embodiment of the liquid jet recording apparatus of the present invention.

FIG. 3 is a block diagram showing an embodiment of a liquid jet recording apparatus of the present invention.

FIG. 4 is a graph showing an example of the relationship between the temperature of the recording head and the droplet amount in the embodiment of the liquid jet recording apparatus of the present invention.

FIG. 5 is an explanatory diagram of an example of a driving method of the liquid jet recording apparatus.

FIG. 6 is a graph showing another example of the relationship between the temperature of the recording head and the droplet amount in the embodiment of the liquid jet recording apparatus of the present invention.

FIG. 7 is a cross-sectional view showing a second example of a recording head in a liquid jet recording apparatus according to an embodiment of the present invention and a partial perspective view of an example of a heater substrate.

FIG. 8 is an explanatory diagram of a volume in an individual liquid flow path from an end portion of each heating element to an ejection port in a second example of the recording head in the embodiment of the liquid jet recording apparatus of the present invention.

FIG. 9 is a partial perspective view of an example of a heater substrate showing a third example of the recording head in the embodiment of the liquid jet recording apparatus of the present invention.

FIG. 10 is a cross-sectional view showing an example of a thermal type liquid jet recording apparatus.

FIG. 11 is a graph showing an example of the relationship between the temperature T of the recording head and the volume Vd of a droplet.

[Explanation of symbols]

1 ... Heater substrate, 2 ... Channel substrate, 3 ... Discharge port, 4 ...
Individual liquid channels, 5 ... Common liquid chamber, 6 ... Pit layer, 7 ... Heating element, 8 ... Bypass section, 11 ... First heating element, 12 ...
2nd heat generating element, 21 ... Recording head, 22 ... Head temperature detection part, 23 ... Driving part.

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-1-237152 (JP, A) JP-A-9-48125 (JP, A) JP-A-3-284951 (JP, A) JP-A-1- 234255 (JP, A) JP 5-293977 (JP, A) JP 8-183187 (JP, A) JP 6-191028 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/175 B41J 2/01

Claims (10)

(57) [Claims] 1. A recording head provided with an energy generating element that generates energy for ejecting a liquid, an individual liquid channel that is a passage of the liquid corresponding to the energy generating element, and an ejection port that ejects the liquid. In the liquid jet recording apparatus having the above, a plurality of individual liquid channels are provided as the individual liquid channels for printing one pixel, and the plurality of individual liquid channels have a plurality of different types of structures. And a head temperature detecting means for detecting the temperature of the recording head, and a temperature of the recording head detected by the head temperature detecting means.
A liquid ejecting recording characterized by including a driving unit that selects an individual liquid channel satisfying the following formula 1 from the plurality of individual liquid channels and drives an energy generating element corresponding to the selected individual liquid channel. apparatus. V _FCL −α> Vd (1) where V _FCL is the volume from the discharge port side end of the energy generating element in the individual liquid flow path to the discharge port, Vd is the volume of the discharged droplet, α is the decrease in the liquid volume in V _FCL due to the receding of the liquid meniscus. 2. The individual liquid flow paths having different structures of different types are formed so as to have different volumes from the end of the energy generating element to the discharge port, and the drive means is According to the temperature of the recording head detected by the head temperature detecting means, when the temperature of the recording head is high, an individual liquid channel of a type having a large volume is selected, and when the temperature of the recording head is low, the volume of the individual liquid flow path is selected. 2. The liquid jet recording apparatus according to claim 1, wherein an individual liquid flow path of a small type is selected to drive the energy generating element corresponding to the selected individual liquid flow path. 3. The energy generating element is provided such that the area of the energy generating element provided in the flow path having a large volume is smaller than the area of the energy generating element provided in the flow path having a small volume. The liquid jet recording apparatus according to claim 2, wherein the liquid jet recording apparatus is provided. 4. The individual liquid flow paths having different structures are formed so that the areas of the energy generating elements are different from each other, and the driving means detects the head temperature detecting means. According to the temperature of the recording head, when the temperature of the recording head is high, an individual liquid flow path of a type having a small area of the energy generating element is selected, and when the temperature of the recording head is low, the energy generating element is selected. 2. The liquid jet recording apparatus according to claim 1, wherein a type of individual liquid channel having a large area is selected to drive the energy generating element corresponding to the selected individual liquid channel. 5. The drive means controls to switch the drive of the energy generating element according to the selection of the individual liquid flow path according to the temperature of the recording head so as not to perform during the printing of one page. The liquid jet recording apparatus according to any one of claims 1 to 4. 6. A recording head provided with an energy generating element that generates energy for ejecting a liquid, an individual liquid channel that is a passage of the liquid corresponding to the energy generating element, and an ejection port that ejects the liquid. In the liquid jet recording apparatus having the above, one individual liquid channel is provided as an individual liquid channel for printing one pixel, and a plurality of different energy generating elements are provided in the individual liquid channel. In addition, a head temperature detecting means for detecting the temperature of the recording head, and energy satisfying the following formula 1 from among the plurality of types of energy generating elements according to the temperature of the recording head detected by the head temperature detecting means A liquid jet recording apparatus comprising a drive unit for selecting and driving a generating element. V _FCL −α> Vd (1) where V _FCL is the volume from the discharge port side end of the energy generating element in the individual liquid flow path to the discharge port, Vd is the volume of the discharged droplet, α is the decrease in the liquid volume in V _FCL due to the receding of the liquid meniscus. 7. The plurality of different types of energy generating elements are formed in the individual liquid flow path so that the volumes from the ejection ports to the ends of the energy generating elements are different from each other, and the driving means includes: According to the temperature of the recording head detected by the head temperature detecting means, an energy generating element having a large volume is selected when the temperature of the recording head is high, and the volume is selected when the temperature of the recording head is low. The liquid jet recording apparatus according to claim 6, wherein an energy generating element of a small type is selected and driven. 8. The energy generating element is provided such that the area of the energy generating element of the large volume type is smaller than the area of the energy generating element of the small volume type. The liquid jet recording apparatus according to claim 7. 9. The plurality of different types of energy generating elements are formed so that their areas are different from each other, and the drive unit is configured to perform the above-mentioned operation according to the temperature of the recording head detected by the head temperature detection unit. When the temperature of the recording head is high, an energy generating element of a type having a small area of the energy generating element is selected, and when the temperature of the recording head is low, an energy generating element of a type having a large area of the energy generating element is selected. The liquid ejecting recording apparatus according to claim 6, wherein the liquid ejecting recording apparatus is driven by being driven. 10. The driving device controls the driving of the energy generating element according to the temperature of the recording head not to be performed during printing of one page. 2. The liquid jet recording apparatus according to item 1.