JPH03101961A - Ink jet recording head - Google Patents

Abstract

PURPOSE:To form a printing boundary with high accuracy by a construction wherein the wall of an orifice plate is disposed on a microdot delivery course (on an extension of a center line of an ink flow path), only a main drip is delivered from an orifice, and microdots are blocked by the wall. CONSTITUTION:A center line of an orifice is inclined through an angle of 0-20 deg. (107) with respect to a center line of an ink flew path 103. Thus, the center of an orifice 102 does not coincide with the center of the ink flow path, and the extension of the center line of the ink flow path 103 reaches the inner surface of the orifice 102. When a heating element 104 generates heat to generate a bubble, a main dot is delivered along an orifice center line 105. Microdots are generated with the extinction of the bubble. However, the microdots fly on a flow path center line 106, therefore abutting on an orifice plate 101 on the lower side of the orifice 102 and having no possibility of being delivered outside a head.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording head, and more particularly to a flow path configuration of the head that improves printing quality. [Prior Art 3] A typical example of a structure and manufacturing method from an orifice plate of an inkjet head to an ink flow path has been devised. This structure is shown in FIG. The center of the orifice and the center of the ink flow path in which the heating element is configured are the same. [Problems to be Solved by the Invention] However, the conventional example described above has the disadvantage that microdots are generated and print quality is degraded. The mechanism by which microdots are generated is shown in Figure 7 i) ~
iii). When energy is applied to the heating element as in i), foaming occurs in the ink flow path and the main droplet is ejected. As the foam disappears, as in ii),
As the ink moves in the direction of the arrow, microdots as shown in iii) are generated due to the impact of the ink coming from the front and back. The ejection course of the microdots is on the center line of the ink flow path. The reason why microdots degrade printing quality is as follows. The print is formed using the main droplet, but unless the microdot is ejected onto the main droplet, it becomes a printing error. As explained in FIG. 2, the microdots are ejected later than the main dots. Furthermore, since the generation mechanism of microdots is different from that of main droplets, the ejection speed is also different, and the speed is generally slower. Even when the ejection delay time and the landing time on the paper are different, the head is still moving on the printer, and a deviation occurs in the landing position determined by the moving speed of the head and the time. Furthermore, as shown in Figure 8, when the orifice is inclined with respect to the ink flow path, the main droplet is ejected on the center line of the orifice, but the microdots are ejected on the center line of the ink flow path. , the impact position will be further away. In practice, the more high-speed printing is performed, the more the microdots become conspicuous, and specifically, they obstruct high definition because they obscure the printing boundaries. As printers become faster, improving microdot printing has become a major issue. [Means for Solving the Problems] According to the present invention, the orifice plate wall is provided on the ejection course of the microdots, that is, on the extension of the center line of the ink flow path, and only the main droplets are ejected from the orifice, but the microdots are ejected from the orifice. , which is blocked by a wall to prevent it from being ejected outside the head. [Example] Figs. 2 to 6 show a preferred inkjet unit IJU, inkjet head IJ, ink tank IT, inkjet cartridge IJC, and inkjet recording device main body IJR to which the present invention is implemented or applied.
FIG. 3A is an explanatory diagram for explaining each of the carriages HC and their relationships. The configuration of each part will be explained below using these drawings. As can be seen from the perspective view of FIG. 3, the inkjet cartridge IJC in this example has a large ink storage ratio, and the tip of the inkjet unit IJ/U is slightly larger than the front surface of the ink tank IT. It has a prominent shape. This inkjet cartridge IJC
is a disposable type that is fixedly supported by a positioning means and electrical contacts (described later) of a carriage HC (FIG. 5) placed on the inkjet recording apparatus main body IJRA, and is detachable from the carriage HC. It is. The configuration shown in FIGS. 2 to 6 of this example includes a configuration to which a number of new technologies that were used at the stage of establishment of the present invention are applied, so the overall explanation will be given while briefly explaining these configurations. I decided to do it. (i) Inkjet unit IJU configuration description The inkjet unit IJU is a bubble jet unit that performs recording using an electrothermal converter that generates thermal energy to cause film boiling in ink in response to electrical signals. be. In Fig. 2, 100 is a structure in which electrothermal converters (discharge heaters) arranged in a plurality of rows on the St base slope and electrical wiring such as 84 for supplying electric power are formed using film-forming technology. This is a heater board consisting of 200 is a wiring board for the heater board 100;
Wiring corresponding to the wiring of the heater board 100 (for example, connected by wire bonding) and a pad 201 located at the end of this wiring and receiving electrical signals from the main device.
It has 1300 is a partition wall for dividing a plurality of ink channels, and a common l{! for storing ink to supply ink to each ink channel. An orifice plate 400 that is a grooved top plate provided with chambers, etc., and has an ink receiving port 1500 that receives ink supplied from the ink tank IT and introduces it into the above-mentioned common liquid chamber, and a plurality of ejection ports corresponding to each ink flow path. It is integrally molded. Although polysulfone is preferable as the integrally molded material, other resin materials for molding may also be used. Reference numeral 300 denotes a support made of metal, for example, which supports the back surface of the wiring board 200 on a flat surface, and serves as a bottom plate of the inkjet unit. Reference numeral 500 denotes a pressing spring, which has an M-shape and presses the common liquid chamber with light pressure at the center of the M-shape, and uses a front sag 501 to concentrate linear pressure on a part of the liquid path, preferably in the area near the discharge port. Press. The foot of the spring that presses the heater board 100 and the top plate 1300 passes through the hole 3121 of the support body 300 and engages with the back side of the support body 300, thereby engaging the two in a state where they are sandwiched between them. The heater board 100 and the top plate 1300 are crimped and fixed by the concentrated biasing force of the spring 500 and its front sagging portion 501. The support body 300 also has positioning holes 312, 1900 and 2000 that engage with the two positioning protrusions 1012 of the ink tank IT and the protrusions 1800 and 1801 for positioning and heat-sealing retention, and also has positioning holes 312, 1900 and 2000 that engage with the two positioning protrusions 1012 of the ink tank IT and the protrusions 1800 and 1801 for positioning and heat sealing holding. It has protrusions 2500 and 2600 for positioning with respect to the HC on the back side. In addition, the support 300 also has a hole 320 that allows an ink supply pipe 2200 (described later) to pass therethrough, which allows ink to be supplied from an ink tank. The wiring board 200 is attached to the support body 300 by adhering it with an adhesive or the like. Note that the recesses 2400 and 2400 of the support body 300 (7) are provided near the positioning protrusions 2500 and 2600, respectively, and in the assembled inkjet cartridge IJC (Fig. 3), the three surrounding sides thereof are parallel to each other. Groove 3
At the extension point of the head tip area formed by a plurality of 000.
．． It is located so that it does not reach 2600. This parallel groove 3000 is formed. As can be seen in FIG. 5, the lid member 800 is attached to an inkjet cartridge IJ.
It forms the outer wall of C, and together with the ink tank, forms a space in which the inkjet unit IJU is housed. In addition, the ink supply member 600 in which the parallel grooves 3001 are formed has an ink conduit 1600 continuous to the ink supply pipe 2200 described above formed as a cantilever with the supply pipe 2200 side fixed, so that the fixed side of the ink conduit and the ink Sealing bottle 60 to ensure capillary action with supply pipe 2200
2 has been inserted. Note that 601 is a packing that seals the connection between the ink tank IT and the supply pipe 2200;
is a filter installed at the tank side end of the supply pipe. Since this ink supply member 600 is molded, it is not only inexpensive and has high positional accuracy and eliminates deterioration in manufacturing precision, but also can be used for mass production due to the cantilevered conduit 1 600. The state of pressure contact with the above-mentioned ink receptacle 1500 can be stabilized. In this example, a more complete communication state can be reliably obtained by simply pouring the sealing adhesive from the ink supply member side under this pressure-contact state. Note that the ink supply member 600 is fixed to the support body 300 through the hole 1901 of the support body 300.
．． This can be easily done by projecting the backside bottle (not shown) of the ink supply member 600 to 1902 through the holes 1901 and 1902 of the support 300, and heat-sealing the protruding portion to the backside of the support 300. be exposed. Note that this slightly protruding area of the heat-sealed back surface is the ink tank I.
Since it is housed in a recess (not shown) in the side wall surface of the inkjet unit IJU mounting surface of the T, the positioning surface of the unit IJU can be accurately obtained. (if) Ink tank IT configuration description After inserting the cartridge body 1000, ink absorber 900, and ink absorber 900 from the side opposite to the unit IJU mounting surface of the cartridge body iooo, insert the ink tank. and a lid member 1100 for sealing. Reference numeral 900 denotes an absorber for impregnating ink, and is disposed within the cartridge body 1000. l200 is a unit I consisting of the above parts 100 to 600.
This is a supply port for supplying ink to the JU, and also controls the ink content of the absorber 900 by injecting ink from the supply port 1200 in a step before placing the unit in the portion 1010 of the cartridge body 1000. It is also an injection port for doing this. In this example, the parts that can supply ink are the air vent and the supply port, but the rib 2300 in the main body 1000 is used to ensure good ink supply from the ink absorber.
and the partial ribs 2500 and 2400 of the lid member 1100.
Since the ink supply port 1 is formed continuously from the 401 side over the farthest corner area from the ink supply port 1 200, a relatively good and uniform ink supply to the absorber can be achieved from the supply port 1200 side. It is important that this is done. This method is extremely effective in practice. This rib 100
0 has four ribs parallel to the carriage movement direction on the rear surface of the ink tank main body 1000 to prevent the absorber from coming into close contact with the rear surface. In addition, the partial ribs 2400 and 2500 are similarly provided on the inner surface of the lid member 1100 on the corresponding extensions to the rib 1000, but unlike the rib 1000, they are in a divided state and are free from the presence of air. The space is increased more than the former. still,
The partial ribs 2500 and 2400 are distributed over half or less of the total area of the lid member 1000. These ribs made it possible to more stably guide the ink in the region of the corner of the ink absorber farthest from the tank supply port 1200 to the supply port 1200 side reliably by capillary force. Reference numeral 1401 denotes an atmosphere ventilation port provided in the lid member to communicate the inside of the cartridge with the atmosphere. 1400 is a liquid repellent material placed inside the atmosphere communication port 1401, which prevents ink from leaking from the atmosphere communication port 1400. The ink storage space of the ink tank IT mentioned above has a rectangular shape, and the long sides are on the sides, so the arrangement of the ribs described above is particularly effective. In the case of a case or a cube, cover member 1
By providing ribs throughout the ink absorber 900, the ink supply from the ink absorber 900 can be stabilized. A rectangular parallelepiped shape is suitable for storing as much ink as possible within a limited space, but in order to use the stored ink for recording without wasting it, as mentioned above, it is necessary to It is important to provide ribs that can perform the above-mentioned action on two adjacent surface areas. Furthermore, the inner surface ribs of the ink tank IT in this embodiment are arranged in a substantially uniform distribution in the thickness direction of the rectangular parallelepiped-shaped ink absorber. This configuration is important because it can equalize the atmospheric pressure distribution and almost eliminate the remaining amount of ink with respect to the ink consumption of the entire absorber. Furthermore, to explain in detail the technical idea behind the arrangement of the ribs, when an arc is drawn with the long side as the radius and centered on the position where the ink supply port 1200 of the ink tank is projected on the quadrangular top surface of the rectangular parallelepiped, ,
It is important to arrange the ribs on the surface outside the arc so that the atmospheric pressure can be quickly applied to the absorbent body located outside the arc. In this case, the atmosphere communication port of the tank is not limited to this example, as long as it is at a position where the atmosphere can be introduced into the region where the ribs are provided. In addition, in this embodiment, the inkjet cartridge I
The rear surface of the JC head is flattened to minimize the space required when incorporated into the device, and the structure maximizes the ink storage capacity, resulting in a more compact device. Not only that, but it also has an excellent structure that reduces the frequency of cartridge replacement. Then, by utilizing the rear part of the space for integrating the inkjet unit IJU, a protruding part for the atmosphere communication port 1401 is formed therein, and the inside of this protruding part is hollowed out, and the above-mentioned absorption An atmospheric pressure supply space 1402 is formed for the entire thickness of the body 900. With this structure, it was possible to provide an excellent cartridge that has not been seen before. Note that this atmospheric pressure supply space 1402 is a much larger space than the conventional one, and the above-mentioned atmospheric air passage port 1401 is located above, so even if the ink leaves the absorber due to some abnormality, this large space will not be affected. The air pressure supply space 1402 can temporarily hold the ink and ensure that the ink is collected by the absorber, thereby providing an excellent cartridge with no waste. Further, the structure of the mounting surface of the unit IJU of the ink tank IT is shown in FIG. Assuming that a straight line L1 passes approximately through the center of the protruding opening of the office plate 400 and is parallel to the mounting reference plane of the bottom of the tank IT or the surface of the carriage, the line 2 that engages with the hole 312 of the support 300
The two positioning protrusions 10l2 are located on this straight line L1. The height of this protrusion 1012 is slightly lower than the thickness of the support 300, and positions the support 300. In this drawing, the carriage positioning hook 4 is located on the extension of the straight line L1.
Claw 21 that engages with the 906 corner engagement surface 4002 of 001
00 is located, and the positioning force on the carriage is in this direction lIIL. It is configured to act in a plane region parallel to the reference plane including the reference plane. As will be described later with reference to FIG. 5, these relationships are effective because the positioning accuracy of only the ink tank is equivalent to the positioning accuracy of the ejection ports of the head. Further, a hole 19 for fixing the support body 300 to the side surface of the ink tank is provided.
Ink tank protrusions 18 corresponding to 00.2000 respectively
00.1801 is longer than the above-mentioned protrusion 1012, and the part that protrudes through the support 300 is thermally fused to form the support 3.
This is for fixing 00 to its side. Assuming that La is a straight line that is perpendicular to the above-mentioned line L1 and passes through this protrusion 1 800, and L2 is a straight line that passes through the protrusion 1801, the approximate center of the supply port 1 200 is located above the straight line L. This is a preferable configuration because it acts to stabilize the connection between the port 1200 and the supply pipe 2200, and reduces the load on the connection due to drops or impacts. or,
straight line L. , L3 do not match, and the presence of protrusions 1800 and 1801 around the protrusion 1012 on the ejection port side of the head IJH further produces a reinforcing effect in positioning the head JH with respect to the tank. Note that the curve indicated by L is the outer wall position when the ink supply member 600 is attached. Since the protrusions 1800 and 1801 are along the curve L4, they provide sufficient strength and positional accuracy even for the weight of the distal end side configuration of the head IJH. Reference numeral 2700 denotes a tip collar of the ink tank IT, which is inserted into a hole in the front plate 4000 of the carriage and is provided in case of an abnormal situation where the displacement of the ink tank becomes extremely poor. Reference numeral 2101 is a retainer for the carriage, which is provided on a bar (not shown) of the carriage HC, and the cartridge IJC may enter below this bar at the position where it is rotated and mounted as described later, and it may be unnecessarily removed from the positioning position. This is a protective member that maintains the attached state even if a force is applied in an upward direction to remove it. The ink tank IT has a shape that surrounds the unit IJU except for the lower opening by covering it with the lid 800 after the unit IJU is installed, but the inkjet cartridge IJC has a lower opening for placing it on the carriage HC. Since it is close to the carriage HC, it forms a substantial four-sided surrounding space. Therefore, although the heat generated from the head IJH in this enclosed space is effective as a heat-retaining space, the temperature rises only slightly during long-term continuous use. For this reason, in this example, a slit 1700 with a width smaller than this space is provided on the upper surface of the cartridge IJC in order to assist the natural heat dissipation of the support, thereby preventing temperature rise and improving the temperature distribution of the entire unit IJU. We were able to make uniformity independent of the environment. When assembled as an inkjet cartridge IJC, ink is supplied from inside the cartridge through the supply port 1 200,
Hole 320 in support 300 and supply tank 600
The ink is supplied into the supply tank 600 through an inlet provided on the inner back surface side, and after passing through the interior, the ink is supplied from the outlet through an appropriate supply pipe and the ink inlet 1500 of the top plate 400 for a common 7-day period. It flows into the room. A packing made of, for example, silicone rubber or butyl rubber is disposed at the above-mentioned connecting portion for ink communication, and this seals the ink supply path to ensure an ink supply path. In this embodiment, the top plate 1300 is made of a resin such as polysulfone, polyethersulfon, polyphenylene oxide, or polypropylene, which has excellent ink resistance, and is molded together with the orifice plate part 400 in a mold. It has been done. As mentioned above, the integrally molded parts include the ink supply member 600,
Top plate and orifice plate integrated, ink tank body 1
000, which not only achieves a high level of assembly accuracy but also is extremely effective in improving quality in mass production. Furthermore, since the number of parts can be reduced compared to the prior art, excellent desired characteristics can be reliably exhibited. In addition, in the embodiment of the present invention, in the above-mentioned shape after assembly,
As shown in FIGS. 2 to 4, the ink supply member 6
00, the upper surface part 603 forms a slit S as shown in FIG.
A slit (not shown) similar to the slit S is formed between the lower lid 800 of the ink tank IT and the head side end 4011 of the thin plate member to which the lower lid 800 of the ink tank IT is bonded. These slits between the ink tank IT and the ink supply member 600 substantially act to further promote heat dissipation from the slit 1700, and even if there is unnecessary pressure applied to the tank IT, this slit can be prevented. This prevents the direct supply member from affecting the inkjet unit IJT. In any case, the above-mentioned configuration of this embodiment is a configuration that has not been seen in the past, and each of them individually provides an effective effect, and in combination, each component provides an organic configuration. ing. (iii) Description of attaching the inkjet cartridge IJC to the carriage HC In FIG. 5, 5000 is a platen roller that guides the recording medium P from the bottom to the top of the page. The carriage HC moves along the platen roller 3000, and has a front plate 40 located on the front side of the inkjet cartridge IJC on the front platen side of the carriage.
00 (thickness: 2 mm) and a flexible sheet 4005 equipped with pads 2011 corresponding to the pads 201 of the wiring board 200 of the cartridge IJC, and for generating elastic force to press this against each pad 20l1 from the back side. An electrical connection support plate 4003 that holds a rubber pad sheet 4007, and an inkjet cartridge IJ.
Positioning hook 400 for fixing C to the recording position
1 is provided. The front plate 4000 has two protruding surfaces 40lO for positioning, corresponding to the aforementioned positioning protrusions 2500 and 2600 of the cartridge support 300, respectively, and after the cartridge is mounted, a vertical force is applied to the protruding surfaces 40lO. For this reason, the reinforcing rib has a plurality of ribs (not shown) on the platen roller side of the front plate facing in the direction of the perpendicular force. This rib is located at the front position L when the cartridge IJC is installed.
A head protection protrusion that protrudes slightly (approximately 0.1 mm) toward the platen roller is also formed. The electrical connection support plate 4003 has a plurality of reinforcing ribs 4004 not in the direction of the ribs but in the vertical direction, and the proportion of lateral protrusion is reduced from the platen side toward the hook 4001 side. This also serves the function of tilting the position when the cartridge is installed as shown in the figure. In addition, in order to stabilize the electrical contact state, the support plate 4003 is used to position the hook side to apply force to the cartridge in the opposite direction to the direction in which the two positioning protruding surfaces 4010 act on the cartridge. It has two surfaces 4006 corresponding to the protruding surfaces 4010, forming a pad contact area between them and uniquely defining the deformation amount of the notch of the rubber seat 4007 with a notch corresponding to the pad 2011. These positioning surfaces come into contact with the surface of the wiring board 300 when the cartridge IJC is fixed at a recordable position. In this example, the wiring board 300
Since the pads 201 are distributed symmetrically with respect to the above-mentioned line L1, the amount of deformation of each notch of the rubber seams 4007 is made uniform, thereby making the contact pressure of the pads 2011 and 201 more stable. The distribution of pads 201 in this example is two rows above, two rows below, and two columns vertically. The hook 4001 has an elongated hole that engages with the fixed shaft 4009, and uses the movement space of the elongated hole to rotate counterclockwise from the position shown in the figure, and then moves to the left along the platen roller 5000. By moving, the inkjet cartridge IJC is positioned with respect to the carriage HC. The hook 4001 may be moved in any way, but a configuration in which it can be moved using a lever or the like is preferable. In any case, when the hook 4001 rotates, the cartridge IJC moves toward the platen roller and moves to a position where the positioning projections 2500 and 2600 can come into contact with the positioning surface 4010 of the front plate,
By moving the hook 400 1 to the left, the hook surface 4002 at 90''' touches the hook 90 of the claw 2100 of the cartridge IJC.
Positioning the cartridge IJC while keeping it in close contact with surface 25.
Pads 00.4010 rotate in a horizontal plane around the contact area between pads 201 and 2011, and finally contact between pads 201 and 2011 begins. When the hook 4001 is held in a predetermined position, that is, a fixed position, the pads 201 and 2011 are in complete contact with each other, the positioning surfaces 2500 and 4010 are in complete contact with each other, and the 90-degree surface 4002 and the 90-degree surface of the claw are brought into contact with each other. The two-surface contact between the two surfaces and the surface contact between the wiring board 300 and the positioning surface 4006 are simultaneously formed, and the holding of the cartridge IJC in the carriage is completed. (iv) General description of the main body of the apparatus FIG. 6 shows an inkjet recording apparatus I to which the present invention is applied.
In the general view of JRA, the carriage HC that engages with the spiral groove 5004 of the lead screw 5005, which rotates via the drive force transmission gears 5011 and 5009 in conjunction with the forward and reverse rotation of the drive motor 5013, is a pin (not shown). ) and is moved back and forth in the directions of arrows a and b. Reference numeral 5002 is a paper holding plate that holds the paper on the platen 5 in the carriage movement direction.
Press against 000. Reference numerals 5007 and 5008 are home position detecting means for confirming the presence of the lever 5006 of the carriage in this area using a photo camera and switching the rotational direction of the motor 5013. Reference numeral 5016 is a member that supports a cap member 5022 that caps the front surface of the recording head, and 5015 is a suction means that sucks the inside of this cap, and performs suction recovery of the recording head through the opening 5o23 in the cap. 50l7 is a cleaning blade, 5
Reference numeral 019 denotes a member that allows this blade to move in the front and back direction, and these are supported by a main body support plate 5018. Needless to say, the blade is not of this type, but a well-known cleaning blade can be applied to this example. Also, 5
012 is a lever for starting suction for arch recovery;
It moves with the movement of the cam 5020 that engages with the carriage, and the movement of the driving force from the drive motor is controlled by known transmission means such as clutch switching. These catching, cleaning, and suction recovery are configured so that the desired processing can be performed at the corresponding positions by the action of the lead screw 5005 when the carriage comes to the home position side area. Any of these can be applied to this example as long as they are activated. Each of the configurations described above is an excellent invention whether viewed singly or in combination, and represents a preferable configuration example for the present invention. In order to explain in detail the present invention technically related to the above-mentioned FIGS. 2 to 6, the following description will be made using FIGS. 1 and 7 and subsequent figures. [Example] Figure 1 shows a typical example of the present invention. 101 is an orifice plate, 102 is an orifice, 103 is an ink flow path, 1
04 is a heating element, 105 is an orifice center line, 106 is a flow path center line, and 107 is an inclination angle between the orifice and the ink flow path. When 104 generates heat and foams, a main dot is ejected onto the orbit of 105. Microdots are generated as the foam disappears, but since the microdots fly on the 106 line,
It hits the lower orifice plate of the orifice and is not discharged outside the head. FIGS. 9 and 10 show other embodiments of the present invention. FIG. 9, 401 is an orifice plate, 402 is an orifice, 403 is an ink flow path, 404 is a heating element, 405
is the orifice centerline, and 406 is the flow path centerline. FIG. 10, 501 is an orifice plate, 502 is an orifice, 503 is an ink flow path, 504 is a heating element, 50
5 is the orifice center line, 506 is the ink flow path center line, 5
07 is the inclination angle between the orifice and the ink flow path. In both inventions, the microdots cannot be ejected on the ejection course of the microdots, that is, on the extension of the center line of the ink flow path, because there is an orifice plate. In the invention shown in FIG. 9, the orifice direction and the ink flow path are parallel, so the center lines do not intersect. [Effects of the Invention] As explained above, microdot printing can be prevented by providing a wall with an orifice plate on the microdot ejection course to prevent the microdots from being ejected outside the head. By eliminating microdot printing, printing boundaries can be made clearer, making it possible to manufacture and supply inkjet heads that are compatible with higher speed printers. Furthermore, since the microdots return into the nozzle, ink consumption can also be reduced. Assuming that 0.6 pl2 microdots are ejected for a 60 pfl main droplet, the savings is 1%.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the ink flow path from the orifice according to the present invention, Fig. 2 is an exploded perspective view of the cartridge of the present invention, Fig. 3 is an assembled perspective view of Fig. 2, and Fig. 4 is an inkjet unit IJU. (7) Perspective view of mounting part, 5th
The figure is an explanatory diagram of how the cartridge IJC is attached to the device, Fig. 6 is an external view of the device of the present invention, Fig. 7 is an explanatory diagram of microdot generation, and Fig. 8 is from the orifice when the ejection courses of the main droplet and the microdot are different. 9 and 10, which are cross-sectional views of the ink flow path, are illustrations of another embodiment of the present invention, and FIG. 11 is an illustration of a conventional example. 101 is an orifice plate, 102 is an orifice, 1
03 is an ink flow path, 103 is a heating element, 105 is a center line of an orifice, 106 is a center line of an ink flow path, 205 is a main droplet, and 206 is a microdot. z41!7ρ L3 /σθl (/tll

Claims (2)

[Claims] (1) In an inkjet recording device having an ink flow path provided with an orifice means for ejecting ink and a thermal energy generating element for ejecting ink, the center of the orifice and the center of the ink flow path do not coincide, and the ink An inkjet recording head characterized in that the center line of the flow path extends to the inner surface of the orifice of the orifice means. (2) The ink jet recording head according to claim 1, wherein the center line of the orifice is inclined from 0° to 20° with respect to the center line of the ink flow path.