CN1313275C - inkjet print head - Google Patents

Abstract

The invention provides an ink jet printing head, which comprises an ink storage body, an air bag, a pressure plate and an elastic device, wherein the ink storage body is provided with a plurality of ink storage holes; the ink storing body has one air inlet gap hole to maintain the pressure inside the ink storing body in one negative pressure range and to hold one ink inside the air inlet gap hole, and the air inlet gap hole has size to make the ink have one surface tension inside the air inlet gap hole and to avoid the ink leakage from the air inlet gap hole to the outside of the ink storing body; the air bag is communicated with the outside of the ink storage body and arranged in the ink storage body in an expandable mode, the pressure plate is adjacent to the air bag and movably arranged in the ink storage body, and the elastic device is arranged in the ink storage body in an abutting mode with the pressure plate and used for limiting the action of the air bag; when the negative pressure in the ink storage body rises, the air bag expands to press the pressure plate, and the outside air breaks through the surface tension of the ink in the air inlet clearance hole and enters the ink storage body from the air inlet clearance hole to reduce the negative pressure in the ink storage body.

Description

inkjet print head

technical field

The present invention relates to an inkjet printhead, and more particularly to an inkjet printhead that substantially reduces assembly time and parts.

Background technique

In the inkjet printhead of commercially available printers, the negative pressure inside the inkjet printhead is mainly used, that is, the pressure slightly lower than the atmospheric pressure exists in the ink storage body of the cartridge, so that it is stored in the general environment In this way, ink leakage will not occur. However, when the inkjet printhead starts to eject ink, the ink in the ink storage body of the inkjet printhead decreases gradually. Since the inkjet printhead belongs to an airtight space, the pressure in the ink storage body will increase with the increase of the internal ink. Therefore, a pressure control device needs to be installed in the inkjet print head to control the negative pressure within a certain range.

Among the currently known inkjet printheads, the pressure control device of the inkjet printhead as proposed in U.S. Patent No. 5,526,030, with reference to Fig. 1 and Fig. 2, it is mainly that a steel ball or a plastic ball 106 is inserted into the ink storage Inside the cylindrical tank 104 of the main body 102 , a plurality of ribs 108 on the inner edge of the cylindrical tank 104 are in contact with the steel balls 106 to form a plurality of tiny gaps 110 . When the negative pressure in the ink storage body 102 rises to 25mbar, the external atmospheric pressure breaks through the surface tension of the internal ink in the tiny gap 110, and the air intake adjusts the pressure in the ink storage body 102. When the pressure balance is reached, the air intake action is stopped.

However, the size of the above-mentioned tiny gap 110 is not easy to control, that is, the size of the outer diameter of the steel ball 106 and the inner diameter of the tank body 104 is not easy to manufacture to the desired size, so that the characteristics of the tiny gap 110 may not be achieved; in addition , when assembling the steel ball 106 in the tank body 104, a certain amount of assembling time is also required.

Again, in U.S. Patent No. 6,213,598, another pressure control device for an inkjet print head is proposed. As shown in FIG. The air bag 416 in the inkjet print head makes the air bag 416 expand. At this time, the spring 414 is compressed at the same time. When the compressed distance reaches the side plate 412 against the reed 330, the negative pressure in the inkjet print head A certain negative pressure value is also reached. At this time, the outside atmosphere passes through the air inlet 340 to push the steel ball 320 away smoothly, so that air enters the inkjet print head, thereby reducing the negative pressure in the inkjet print head. After the negative pressure in the inkjet printhead decreases, the air bag 416 will no longer expand, and the spring 414 will reduce the compression, so that the reed 330 returns to the original position pressing the steel ball 320. Such a cycle of repeated actions makes the inkjet printhead The pressure is continuously maintained within a fixed pressure range.

However, the assembling process of the above-mentioned inkjet print head is extremely complicated, which includes heat-melting a reed 330 formed of sheet metal to the bottom of the ink storage body 400, so that it can press the steel ball 320 of the bubble generator with elastic force, because it is in the ink storage The position at the bottom of the main body 400, so it is not easy to place it in position when assembling; in addition, the spring 414 for preloading the air bag 416 is assembled to the stainless steel side plate 412 for fixing, and both are simultaneously installed into the ink storage body In the manufacturing process of 400, the process is quite time-consuming and has low reliability.

Contents of the invention

In view of this, the object of the present invention is to provide an inkjet print head, which can greatly reduce assembly time and parts.

Another object of the present invention is to provide an inkjet printing head, the pressure regulating air intake structure and the ink storage body are integrally formed.

According to the present invention, an inkjet printing head is provided, which includes an ink storage body, an air bag, a pressure plate, and an elastic device; wherein the ink storage body has an air intake clearance hole, and maintains a negative pressure therein , and accommodate an ink in it, the size of the air intake clearance hole makes the ink have a surface tension in the air intake clearance hole, so that the ink will not leak from the air intake clearance hole outside the ink storage body; the air bag and the ink storage The outside of the main body communicates with the ink storage body in an expandable manner, the pressure plate is adjacent to the air bag and is movably disposed in the ink storage body, and the elastic device is arranged in the ink storage body in a contact with the pressure plate Inside, it is used to limit the action of the air bag; when the negative pressure in the ink storage body rises, the air bag expands and presses the pressure plate, and the outside air breaks through the surface tension of the ink in the air intake gap hole, and the air from the air intake gap hole Enter the ink storage body to reduce the negative pressure in the ink storage body.

In a preferred embodiment, the width of the air intake clearance hole may be 0.05-0.1 mm, and a preferred width may be 0.06 mm.

In another preferred embodiment, the ink storage body has a first end and a second end, and an air intake gap hole is formed between the first end and the second end.

Also, the first end portion has a first surface facing the inside of the ink storage body, and the second end portion has a second surface facing the outside of the ink storage body, and the air intake clearance hole is formed on the first surface and the second surface. between two surfaces.

Also, the first end portion has a third surface facing the second end portion, and the second end portion has a fourth surface facing the first end portion, and the air intake clearance hole is formed on the third surface and the first end portion. between the four surfaces.

It should be understood that the surface of the first end portion facing the second end portion may be a slope, and the shape of the air intake clearance hole may be a rectangle.

In another preferred embodiment, the ink storage body has a base, a support frame, and a blocking sheet, and the support frame connects the base and the blocking sheet, and the air intake gap hole is formed between the base and the blocking sheet, and is for the ring.

In another preferred embodiment, the ink storage body is provided with a first opening, and the air bag is provided with a second opening communicating with the first opening, and the elastic device can be a spring.

Also in the present invention, another inkjet print head is provided, which includes an ink storage body, a pressure regulating air intake structure, an air bag, a pressure plate, and an elastic device; wherein the ink storage body maintains a Negative pressure, and accommodate an ink in it, the pressure adjustment air intake structure is arranged on the ink storage body, and has an air intake clearance hole, the size of which makes the ink generate a surface tension in the air intake clearance hole, so that the ink will not Leaking from the air intake clearance hole outside the ink storage body; the air bag communicates with the outside of the ink storage body and is arranged in the ink storage body in an expandable manner, and the pressure plate is adjacent to the air bag and is movably arranged in the ink storage body In the main body, the elastic device is arranged in the ink storage body in a contact with the pressure plate to limit the movement of the air bag; when the negative pressure in the ink storage body rises, the air bag expands and presses the pressure plate, and the outside air Break through the surface tension of the ink in the air intake clearance hole, and enter the ink storage body from the air intake clearance hole, so as to reduce the negative pressure in the ink storage body.

In a preferred embodiment, the pressure regulating air intake structure is integrally formed on the ink storage body by injection molding.

In another preferred embodiment, the pressure-regulating air intake structure can be made of metal, and the pressure-regulating air intake structure can be set on the ink storage body by injection molding, or welded to the ink storage body by hot-melt processing. On the ink body.

Description of drawings

Fig. 1, Fig. 2 are the schematic diagrams of the pressure control device of the inkjet print head cartridge proposed by the US Patent No. 5,526,030;

Fig. 3 is the schematic diagram of the pressure control device figure of the ink-jet cartridge that No. 6213598 of the United States Patent proposes;

Fig. 4 is the schematic diagram of the first embodiment of the inkjet printing head of the present invention;

Figure 5a is a perspective enlarged view of part A in Figure 4;

Figure 5b is an enlarged view of part A in Figure 4;

Figure 6 is a schematic diagram of a second embodiment of the inkjet print head of the present invention;

7 is a schematic diagram of a third embodiment of the inkjet print head of the present invention;

Figure 8a is a perspective enlarged view of part A in Figure 7;

Figure 8b is an enlarged view of part A in Figure 7;

Figure 9a is a schematic diagram of a fourth embodiment of the inkjet printhead of the present invention;

Figure 9b is an enlarged view of part A in Figure 9a;

Figure 10a is a schematic diagram of a fifth embodiment of the inkjet printhead of the present invention;

Figure 10b is a partial bottom view of the inkjet printhead in Figure 10a;

Figure 10c is an enlarged view of part B-B' in Figure 10b; and

Fig. 10d is a partial sectional view along line A-A' of Fig. 10b.

Symbol Description:

102-Ink storage body

104-cylindrical tank

106-steel ball

108-convex rib

110 - tiny gap

200, 200a, 200b, 200c, 200d - inkjet print head

210, 210a, 210b, 210c, 210d-ink storage body

211, 211b, 211c, 211d - air intake clearance holes

212, 212a, 212b, 212c - first end

212' - first surface

212b' - third surface

212c'-bevel

212d-Base

213, 213a, 213b, 213c - second end

213' - second surface

213b' - fourth surface

213d-support frame

214d-blocker

215 - first opening

220-air bag

221 - second opening

230-pressure plate

240 - elastic device

250a-Pressure regulation intake structure

251a-air intake clearance hole

300-cassette

320-steel ball

330-Reed

340 - air inlet

412-side panel

414-spring

416-air bag

418-connection hole

Detailed ways

In order to make the above and other objects, features, and advantages of the present invention more comprehensible, a preferred embodiment will be described in detail below together with the accompanying drawings.

first embodiment

Fig. 4, Fig. 5 a, Fig. 5 b show the first embodiment of the inkjet printing head of the present invention, in this embodiment, the inkjet printing head 200 comprises an ink storage body 210, an air bag 220, a pressure plate 230, and an elastic device 240 .

The ink storage body 210 is used to accommodate an ink therein and maintain a negative pressure therein, and has an air intake clearance hole 211, a first end portion 212, and a second end portion 213 at its bottom, wherein The first end portion 212 has a first surface 212′ facing the inside of the ink storage body 210, and the second end portion 213 has a second surface 213′ facing the outside of the ink storage body 210, and the air intake clearance hole 211 is It is formed between the first surface 212' and the second surface 213'; in addition, the ink storage body 210 has a first opening 215 at the top.

It should be understood that the size of the air intake clearance hole 211 enables the ink in the ink storage body 210 to generate a surface tension in the air intake clearance hole 211, so that the ink will not leak from the air intake clearance hole 211 to the ink storage body 210 In addition, therefore, the width w of the air intake clearance hole 211 is preferably between 0.05 mm and 0.1 mm, and the most optimal width is 0.06 mm.

The air bag 220 has a second opening 221 , which communicates with the first opening 215 of the ink storage body 210 , thereby communicates with the outside through the ink storage body 210 , and is disposed in the ink storage body 210 in an inflatable manner.

The pressure plate 230 is adjacent to the air bag 220 and is movably arranged in the ink storage body 210 . The elastic device 240 is arranged in the ink storage body 210 in contact with the pressure plate 230 to limit the movement of the air bag 220 . Action, it should be understood that the elastic device 240 can be a spring.

The configuration of the inkjet print head 200 of the present embodiment is as described above, and the principle of its operation will be described below.

When the inkjet print head 200 performs ink ejection, the negative pressure in the ink storage body 210 rises, and since the air bag 220 communicates with the atmosphere through the second opening 221 and the first opening 215, the air bag 220 follows the ink storage body 210 The negative pressure inside rises and expands, and presses the pressure plate 230 . When the internal negative pressure of the ink storage body 210 continues to rise, and the pressure difference between the atmospheric pressure (outside air) and the internal pressure of the ink storage body 210 reaches the surface tension that can break through the ink in the air intake gap hole 211, the external air will flow from the air intake gap. The hole 211 supplements into the ink storage body 210 to reduce the negative pressure inside the ink storage body 210 and maintain the negative pressure inside the ink storage body 210 within a negative pressure range.

Comparing this embodiment with the inkjet print head in U.S. Patent No. 5,526,030, it can be seen that since the shape of the air intake clearance hole in this embodiment is substantially rectangular, it is not like the known annular shape. Easy to measure.

Also, compare the present embodiment with the inkjet print head in US Pat. No. 6,213,598, and organize the results in the table below. U.S. Patent No. 6,213,598 This example Reed mold Group 1 none steel ball 1 piece none Formation time 15 seconds none Assembly reed loose fault 1.5-2.5% chance of occurrence none Ultrasonic welding causes steel balls to fall off 2-3% chance of occurrence none

It can be seen from the above table that in this embodiment, since the air intake gap hole is integrally formed on the ink storage body, it can avoid the combination error caused by the traditional inkjet print head when it is assembled; In addition to components and man-hours, it does not affect the required print quality.

In addition, in the mold making of the inkjet print head of this embodiment, the male mold core and the female mold core can be processed by a precision mold bed respectively, and the processing size of the mold is very easy to control; The shrinkage rate of injection is about 4.5/1000-6/1000, so the size of the injection-molded intake clearance hole can be controlled between 0.06-0.08mm.

second embodiment

Fig. 6 shows the second embodiment of the inkjet printhead of the present invention. In this embodiment, the inkjet printhead 200a includes an ink storage body 210a, a pressure regulating air intake structure 250a, an air bag 220, and a pressure plate 230, and an elastic device 240, it should be understood that the same configuration as the first embodiment is omitted from its description, and marked with the same symbols.

The difference between this embodiment and the first embodiment is that the air intake clearance hole 251a is formed on the pressure regulating air intake structure 250a outside the ink storage body 210a, that is, the air intake clearance hole is not limited to that of the first embodiment. Generally, it needs to be integrally formed on the ink storage body.

It should be understood that the pressure regulating air intake structure 250a can be disposed on the ink storage body 210a in various ways, for example, when the pressure regulating air intake structure 250a is made of plastic, it can be integrally formed by injection molding On the ink storage body 210a, or when the pressure adjustment air intake structure 250a is made of metal, the pressure adjustment air intake structure 250a can be set on the mold of the ink storage body 210a by injection molding, or by heat The ink storage body 210a is melted and welded.

Since this embodiment does not need to be provided with parts such as steel balls as in the prior art, it can greatly reduce the related components and man-hours required for assembly.

third embodiment

Fig. 7, Fig. 8a, Fig. 8b show the third embodiment of the inkjet printing head of the present invention, in this embodiment, the inkjet printing head 200b comprises an ink storage body 210b, an air bag 220, a pressure plate 230, As well as an elastic device 240, it should be understood that the description of the same structure as the first embodiment is omitted, and the same symbols are used.

This embodiment differs from the first embodiment in that: the ink storage body 210b has an air intake clearance hole 211b, a first end portion 212b, and a second end portion 213b, wherein the first end portion 212b has a A third surface 212b' of the end portion 213b, and the second end portion 213b has a fourth surface 213b' facing the first end portion 212b, and the air intake clearance hole 211b is formed on the third surface 212b' and the fourth surface 212b'. between surfaces 213b'.

From the composition of this embodiment, it can be seen that the formation of the air intake clearance hole is not limited to the first embodiment, and since the difference between this embodiment and the first embodiment is only the formation of the air intake clearance hole, this embodiment can also be The same effect as that of the first embodiment is achieved.

Fourth embodiment

Fig. 9 a, Fig. 9 b show the fourth embodiment of the inkjet printing head of the present invention, in this embodiment, the inkjet printing head 200c comprises an ink storage body 210c, an air bag 220, a pressure plate 230, and an elastic As for the device 240, it should be understood that the description of the same configuration as the first embodiment is omitted, and the same symbols are used.

This embodiment differs from the first embodiment in that: the ink storage body 210c has an air intake clearance hole 211c, a first end portion 212c, and a second end portion 213c, wherein the first end portion 212c faces the second end The surface of the portion 213c may be a slope 212c', and the air intake clearance hole 211c is formed between the first end portion 212c and the second end portion 213c.

From the composition of this embodiment, it can be seen that the formation of the air intake clearance hole is not limited to the first embodiment, and since the difference between this embodiment and the first embodiment is only the formation of the air intake clearance hole, this embodiment can also be The same effect as that of the first embodiment is achieved.

fifth embodiment

Fig. 10a, Fig. 10b, Fig. 10c, Fig. 10d show the fifth embodiment of the inkjet printing head of the present invention, in this embodiment, the inkjet printing head 200d comprises an ink storage body 210d, an air bag 220, a pressure Plate 230, and an elastic device 240, it should be understood that the same structure as the first embodiment omits its description, and is marked with the same symbols; in addition, it should be noted that Fig. 10c and Fig. 10d are drawn along different section lines The drawn cross-sectional view, wherein Fig. 10d is a cross-section along the support frame 213d.

This embodiment differs from the first embodiment in that: the ink storage body 210d has a base 212d, a support frame 213d, a blocking sheet 214d, and an air intake clearance hole 211d at its bottom, wherein the support frame 213d connects the base 212d and The blocking piece 214d, and the air intake clearance hole 211d is formed between the base 212d and the blocking piece 214d, and is annular.

To be more specific, in this embodiment, the required plastic material is introduced into a required annular air intake clearance hole 211d structure mainly through the design of the supporting frame 213d. In terms of mold making in this design, the core of the mold is mainly processed by lathe, followed by electrical discharge machining, and then ground after electrical discharge machining. In addition, the air intake clearance holes are processed by grinding machine.

From the composition of this embodiment, it can be seen that the formation of the air intake clearance hole is not limited to the first embodiment, and since the difference between this embodiment and the first embodiment is only the formation of the air intake clearance hole, this embodiment can also be The same effect as that of the first embodiment is achieved.

Claims (15)

1. An inkjet printing head, comprising: An ink storage body has a first end and a second end, and an air intake clearance hole is formed between the first end and the second end, and a negative pressure, and accommodate an ink therein, wherein the size of the air intake clearance hole makes the ink have a surface tension in the air intake clearance hole, so that the ink will not leak from the air intake clearance hole into the ink storage body outside; An air bag communicates with the outside of the ink storage body and is arranged in the ink storage body in an expandable manner; a pressure plate, adjacent to the air pocket and movably disposed within the ink storage body; and An elastic device is arranged in the ink storage body in a manner of abutting against the pressure plate to limit the movement of the air bag; Wherein, when the negative pressure in the ink storage body rises, the air bag expands to press the pressure plate, and the outside air breaks through the surface tension of the ink in the air intake clearance hole, and enters the air intake clearance hole from the air intake clearance hole. In the ink storage body, to reduce the negative pressure in the ink storage body. 2. The inkjet printhead according to claim 1, wherein the air intake clearance hole has a width of 0.05-0.1 mm. 3. The inkjet printhead according to claim 2, wherein the air intake clearance hole has a width of 0.06mm. 4. The inkjet printhead according to claim 1, wherein the first end has a first surface facing the inside of the ink storage body, and the second end has a surface facing the outside of the ink storage body The second surface, and the air intake clearance hole is formed between the first surface and the second surface. 5. The inkjet print head according to claim 1, wherein the first end has a third surface facing the second end, and the second end has a third surface facing the first end The fourth surface, and the air intake clearance hole is formed between the third surface and the fourth surface. 6. The inkjet print head according to claim 1, wherein a surface of the first end facing the second end is an inclined surface. 7. The inkjet print head according to claim 1, wherein the shape of the air intake clearance hole is a rectangle. 8. The inkjet print head according to claim 1, wherein the ink storage body has a first opening, and the air bag has a second opening communicating with the first opening. 9. The inkjet print head according to claim 1, wherein the elastic device is a spring. 10. An inkjet print head, comprising: An ink storage body has a base, a support frame, and a blocking sheet, wherein the support frame connects the base and the blocking sheet, and an air intake clearance hole is formed between the base and the blocking sheet, and The ink storage body maintains a negative pressure and accommodates an ink therein. The size of the air intake gap makes the ink have a surface tension in the air intake gap, so that the ink will not flow from the air intake gap. The hole leaks out of the ink storage body; An air bag communicates with the outside of the ink storage body and is arranged in the ink storage body in an expandable manner; a pressure plate, adjacent to the air pocket and movably disposed within the ink storage body; and An elastic device is arranged in the ink storage body in a manner of abutting against the pressure plate to limit the movement of the air bag; Wherein, when the negative pressure in the ink storage body rises, the air bag expands to press the pressure plate, and the outside air breaks through the surface tension of the ink in the air intake clearance hole, and enters the air intake clearance hole from the air intake clearance hole. In the ink storage body, to reduce the negative pressure in the ink storage body. 11. The inkjet print head according to claim 10, wherein the air intake clearance hole is annular in shape. 12. The inkjet print head according to claim 10, wherein the ink storage body has a first opening, and the air bag has a second opening communicating with the first opening. 13. The inkjet print head according to claim 10, wherein the elastic device is a spring. 14. The inkjet printhead according to claim 10, wherein the air intake clearance hole has a width of 0.05-0.1 mm. 15. The inkjet print head according to claim 14, wherein the width of the air intake clearance hole is 0.06 mm.

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