JP2009184183A - Inkjet recording head and inkjet recording device equipped with inkjet recording head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording head having a damper mechanism capable of effectively exhibiting a damping effect associated with a pressure variation of an ink by spreading the ink over a wide range in an ink reservoir. <P>SOLUTION: In the damper mechanism 13, an ink ejection port 21 is disposed at an end on an upper side (side in a direction shown by an arrow A) in a vertical direction of the ink reservoir 16, whereby the ink is spread over the wide range in the ink reservoir 16, and the damping effect associated with the pressure variation of the ink is effectively exhibited. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ink jet recording head capable of absorbing excessive pressure fluctuations of ink generated by acceleration of a carriage, and an ink jet recording apparatus equipped with the ink jet recording head.

  Conventionally, a technique disclosed in Patent Document 1 is known as this type of inkjet recording head. In the ink jet printer disclosed in Patent Document 1, a recording head is mounted on a carriage so as to be reciprocally driven along a guide shaft and to face a platen. In addition, an ink tube for supplying ink from the ink tank is connected to the recording head, and the ink supplied through the ink tube is ejected through the nozzle hole of the recording head and is thereby mounted on the platen. Predetermined printing is performed on the printed recording paper.

In the ink jet head as described above, the pressure in the ink tube that supplies ink to the recording head fluctuates due to the acceleration that occurs when the recording head reciprocates along the guide shaft, and the nozzle hole of the recording head However, in order to prevent such fluctuations in ink pressure, a damper is placed in the middle of the ink tube that supplies ink from the ink tank to the recording head. A member is provided. The damper member is provided with an ink storage part for temporarily storing ink inside a flexible film bag, and the recording head as described above reciprocates along the guide shaft by the ink storage part. It is designed to absorb pressure fluctuations when doing so.
Japanese Patent Laid-Open No. 5-201015

  By the way, in the ink jet printer described above, the acceleration of the recording head that runs along the guide shaft increases with the recent increase in printing speed, thereby increasing the variation range of the ink pressure. However, since the member of the damper described above has the same ink supply port and ink discharge port provided in the film bag, and these are arranged at the lower end in the vertical direction of the ink storage portion (T-shaped branch tube) In addition, it is difficult for ink to be supplied to the ink reservoir in the film bag, and the ink is immediately discharged without spreading over a wide area in the ink reservoir, so that the damping effect can be effectively exhibited. It was difficult. That is, the above-described damper member has a low pressure buffering capacity of the film bag, a positive pressure fluctuation that occurs when the recording head moves to one side, and a negative pressure that occurs when the recording head moves to the other side. There was a problem that fluctuations could not be absorbed effectively.

  SUMMARY OF THE INVENTION The present invention is intended to solve the problems of the prior art, and allows ink to be distributed over a wide range in the ink reservoir so that the damping effect accompanying ink pressure fluctuation can be effectively exhibited. An object of the present invention is to provide an ink jet recording head having a damper mechanism that can be used, and an ink jet recording apparatus equipped with the ink jet recording head.

  In order to achieve the above object, the present invention provides an ink jet recording head that discharges ink supplied through an ink supply path from a nozzle hole and prints it on a recording material. A damper mechanism that absorbs pressure fluctuation is provided. The damper mechanism directs the ink supplied from the ink tank to the internal ink reservoir, and directs the ink in the ink reservoir to the nozzle hole. An ink discharge port for discharging, and the ink storage portion is formed of a plurality of films.

According to the ink jet recording head configured as described above, since the ink storage portion is formed of a plurality of films, it is possible to provide the ink storage portion with flexibility and accompany fluctuations in ink pressure. The damping effect can be exhibited effectively.
Here, in the ink jet recording head of the present invention, the ink discharge port is arranged at an upper end portion in a vertical direction of the ink storage portion.
According to the ink jet recording head configured as described above, since the ink discharge port of the damper mechanism is arranged at the upper end in the vertical direction of the ink storage unit, the ink supplied from the ink supply port into the ink storage unit is discharged. The ink can be discharged from the ink discharge port after flowing upward against the gravity, and this ink is spread over a wide area in the ink reservoir until it reaches the ink discharge port. be able to. Therefore, the damping effect accompanying the ink pressure fluctuation can be effectively exhibited.
In this configuration, the ink discharge port may be positioned above the ink supply port in the vertical direction. Further, the ink supply port may be opened upward in the vertical direction. In this case, the ink can be vigorously entered into the ink storing portion, and the above-described effects can be reliably achieved.

  In the ink jet recording head of the present invention, as the damper mechanism, the ink storage portion is accommodated in the flexible film formed in the flexible film, and stored in the ink storage portion. And a spring member for restricting the flexible film from being deformed by a predetermined value or more with a change in ink pressure.

  In the damper mechanism of the ink jet recording head configured as described above, a spring member is accommodated in the flexible film, and the flexible film deforms more than a set value due to ink pressure fluctuation by the spring member. Since the regulation is performed, the flexible film can be held in a stable shape by the elastic force of the spring member even if the ink pressure largely fluctuates to the plus side or the minus side.

  In the ink jet recording head of the present invention, as the damper mechanism, a plurality of flexible films having an ink storage portion formed therein, and the flexible films are stored in the ink storage portion. And a cover member for restricting the flexible film from being deformed outward by a set value or more in accordance with pressure fluctuation of the ink.

  In the damper mechanism of the ink jet recording head configured as described above, a plurality of flexible films in which the ink storage portion is formed are housed in the cover member, and the pressure change of the ink is prevented by the cover member. Accordingly, since the flexible film is restricted from being deformed outward beyond the set value, the cover member suppresses excessive deformation of the flexible film even if a large fluctuation in ink pressure occurs. The flexible film can be held in a stable shape.

  In the ink jet recording head of the present invention, the plurality of flexible films are formed in a bag shape, and the peripheral portion of the bag body is formed in a gusset shape.

  In the damper mechanism of the ink jet recording head configured as described above, since the bag body is in the form of a gusset, the capacity of the ink reservoir can be increased, and pressure fluctuation can be effectively absorbed.

  In the ink jet recording head of the present invention, both the ink supply port and the ink discharge port are provided at the upper end in the vertical direction of the flexible film formed in the bag shape.

  In the damper mechanism of the ink jet recording head configured as described above, since both the ink supply port and the ink discharge port are provided at the upper end in the vertical direction of the flexible film, the remaining three edge portions (both sides, the lower end) ) Can be formed in a gusset shape, and also in this respect, the capacity of the ink reservoir can be increased.

  In the ink jet recording head of the present invention, the damper mechanism is attached to the recording head.

  In the ink jet recording head configured as described above, since the damper mechanism is provided in the vicinity of the nozzle hole from which ink is ejected, the ink supply to the nozzle hole can be stabilized.

  Further, the present invention is characterized in that an ink jet recording apparatus is configured by mounting an ink jet recording head.

  In the ink jet recording apparatus configured as described above, the above-described damper mechanism is mounted on the ink jet recording head, thereby enabling stable printing on a recording material.

  According to the ink jet recording head configured as described above, since the ink storage portion is formed of a plurality of films, it is possible to provide the ink storage portion with flexibility and accompany fluctuations in ink pressure. The damping effect can be exhibited effectively. In addition, since the ink discharge port of the damper mechanism is arranged at the upper end in the vertical direction of the ink reservoir, the ink from the ink supply port can be spread over a wide area in the ink reservoir, and the ink pressure There is an effect that the damping effect accompanying the fluctuation can be effectively exhibited.

  Embodiments of the present invention will be described below with reference to FIGS. First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall view of an ink jet recording apparatus 100 according to the present invention. In FIG. 1, what is denoted by reference numeral 1 is a recording head block. The recording head block 1 is provided so as to be able to reciprocate along a guide shaft 2 provided in an apparatus main body (not shown). The recording head block 1 is supplied with ink from an ink tank 3. For this purpose, an ink tube (ink supply path) 4 is connected to a flexible printed board 5 that supplies a drive signal for performing a printing process.

  As shown in FIG. 2, the recording head block 1 includes a plurality of recording heads 10 and a carriage 11 that arranges these recording heads 10 along the length direction of the guide shaft 2. Reference numeral 10 denotes a recording head main body 12 having a nozzle hole (not shown) for discharging ink, and a damper mechanism provided in the middle of the ink tube 4 to absorb pressure fluctuations of ink supplied to the recording head main body 12. 13. An ink tube 4 to which ink in the ink tank 3 is supplied is connected to the recording head main body 12, and the ink supplied through the ink tube 4 is ejected from a nozzle hole (not shown) of the recording head 10. Then, predetermined printing is performed on the recording paper P positioned between the nozzle hole and a platen (not shown) arranged to face the nozzle hole.

  Further, as shown in FIGS. 3 and 4, the damper mechanism 13 provided in the recording head 10 includes a casing 15 having a lid 14 serving as a housing, and an ink storage portion housed in the casing 15. 16 includes an ink bag 17 in which 16 is formed, and a cover member 18 serving as a cover for the ink bag 17.

  As shown in FIG. 4, the ink bag 17 is formed by laminating the peripheral portions of two flexible films 19 and forming an ink storage portion 16 inside the flexible film 19. An ink supply port 20 that guides ink supplied from the ink tank 3 to the internal ink reservoir 16 is provided on one side of the flexible film 19, and on the other side of the flexible film 19. An ink discharge port 21 that discharges ink in the ink storage unit 16 toward the nozzle hole is provided on the side portion. The ink supply port 20 is arranged at the lower end in the vertical direction of the flexible film 19, communicates with the lower end in the vertical direction in the ink reservoir 16, and opens toward the upper side in the vertical direction (arrow A direction side). Yes. The ink discharge port 21 is disposed at the upper end in the vertical direction of the flexible film 20, communicates with the upper end in the vertical direction in the ink reservoir 16, and opens toward the lower side in the vertical direction.

In such a damper mechanism 13 of the recording head 10, the ink discharge port 21 communicates with the upper end in the vertical direction in the ink storage unit 16, so that the ink supply port 20 supplies the ink into the ink storage unit 16. It is possible to discharge the ink that has flowed upward against gravity, and then discharge it from the ink discharge port 21. The ink is stored in the ink reservoir 16 before reaching the ink discharge port 21. It can be spread over a wide area. Therefore, the damping effect accompanying the ink pressure fluctuation can be effectively exhibited.
Furthermore, since the ink reservoir 16 is formed of a plurality of flexible films 19, it is possible to provide the ink reservoir 16 with flexibility and effectively exhibit the damping effect associated with ink pressure fluctuations. Can be made.

  In addition, the cover member 18 prevents the flexible film 19 from being deformed outward by a set value or more due to a change in ink pressure in the ink reservoir 16. Even if the cover member 18 causes a large fluctuation in ink pressure, the cover member 18 suppresses excessive deformation of the flexible film 19 and holds the flexible film 19 in a stable shape. be able to.

  In the damper mechanism 13 of the inkjet recording head 10 configured as described above, the ink discharge port 21 is disposed so as to open toward the upper side in the vertical direction (arrow A direction side). Thus, a constant amount of ink can be always stored in the ink storage section 16, and the effect of effectively exhibiting the damping effect associated with the ink pressure fluctuation is exhibited. Further, since the damper mechanism 13 is attached to the recording head 10 and is provided in the vicinity of the nozzle hole of the recording head main body 12 from which ink is ejected, the ink supply to the nozzle hole can be stabilized. Is also played.

  Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment differs from the first embodiment in the configuration of the damper mechanism 31 in the recording head 30 (see FIG. 1). As shown in FIGS. 5 and 6, the damper mechanism 31 includes an ink bag 34 in which the peripheral portions of two flexible films 32 are bonded together to form an ink storage portion 33 therein, and an ink bag 34. The spring member 35 is loaded therein, and a casing 36 (see FIG. 8) that houses the ink bag 34 loaded with the spring member 35 therein.

As shown in FIGS. 5 and 6, an ink supply port that guides the ink supplied from the ink tank 3 to the internal ink reservoir 33 is provided on one side of the flexible film 32 constituting the ink bag 34. 37 is provided, and an ink discharge port 38 for discharging the ink in the ink storage portion 33 toward the nozzle holes is provided on the other side portion of the flexible film 32.
The ink supply port 37 is arranged at the lower end in the vertical direction of the flexible film 32, communicates with the lower end in the vertical direction in the ink storage portion 33, and opens toward the upper side in the vertical direction (arrow A direction side). Yes. The ink discharge port 38 is disposed at the upper end portion in the vertical direction of the flexible film 32, communicates with the upper end portion in the vertical direction in the ink storage portion 33, and opens downward in the vertical direction.

  As shown in FIG. 7, the spring member 35 is disposed so that a pair of plate members 39 have a predetermined interval, and allows elastic deformation in a direction in which the plate members 39 approach or separate from each other. Further, the central part thereof is coupled by the elastic member 40, and the outer surfaces of these plate members 39 are arranged on the inner surface of the flexible film 32.

  The spring member 35 is located at the position shown in FIG. 8B in a steady state where there is no fluctuation in the ink pressure, and the plate members 39 are arranged at a set interval indicated by the symbol (A). A predetermined amount of ink is stored in the ink storage portion 33 formed in the first step. However, when ink flows into the ink reservoir 33 due to the reciprocation of the head block 1 along the guide shaft 2 and the pressure of the ink in the ink reservoir 33 increases, the ink bag 34 expands. As shown in FIG. 8A, the elastic member 40 is elastically deformed to increase the interval (A) between the plate members 39, thereby increasing the capacity of the ink reservoir 33 and absorbing the ink pressure fluctuation. On the other hand, when the ink pressure in the storage portion 33 decreases, the elastic member 40 is elastically deformed as shown in FIG. ) Is reduced, thereby reducing the capacity of the ink reservoir 33 to absorb ink pressure fluctuations. Even if the capacity of the ink reservoir 33 changes due to the fluctuation of the ink pressure in this way, and the flexible film 32 of the ink bag 34 expands or contracts accordingly, FIG. 8A to FIG. As shown by C), the change in the shape of the flexible film 32 is restricted by the elastic force of the elastic member 40 of the spring member 35, whereby the ink bag 34 is maintained in a certain shape.

In the damper mechanism 31 of the ink jet recording head 30 configured as described above, the spring member 35 is provided on the two flexible films 32 constituting the ink bag 34, and the spring member 35 causes the ink pressure to vary. Since the flexible film 32 is restricted from being deformed more than the set value, even if the ink pressure greatly fluctuates to the plus side or the minus side, the spring member 35 suppresses excessive deformation of the flexible film 32. The flexible film 32 can be held in a stable shape.
Further, since the plate member 39 is disposed on the inner surface of the movable film 32, even if the ink bag 34 is reduced as shown in FIG. It is possible to prevent sticking, and the shape of the ink bag 34 can be more reliably stabilized.

In addition, in the said embodiment, there exists a modification as shown below.
(1) The ink supply port 37 is disposed on one side of the ink bag 34 and the ink discharge port 38 is disposed on the other side of the ink bag 34. However, the present invention is not limited to this. As shown in FIG. 4, an ink supply port 41 that supplies ink from the ink tank 3 to the ink storage portion 33 and an ink discharge port that discharges ink in the ink storage portion 33 to the nozzle holes are formed in the upper end portion 34A of the ink bag 34. You may make it provide the exit 42 together. Then, by providing both the ink supply port 41 and the ink discharge port 42 at the upper end 34A of the ink bag 34, as shown in FIG. 10, the remaining three edges (both sides 34B and 34C, The lower end portion 34D) can be formed in a gusset shape (denoted by reference numeral 43), whereby the capacity of the ink storage portion 33 can be increased.
When the ink bag 34 is formed in a gusset shape as described above, a cover member 45 as shown in FIG. 13 may be provided in place of the spring member 35. The cover member 45 includes two cover plates 46 and a support member 47 that is provided so as to surround the end portions of the cover plates 46 and supports the cover plates 46 so as to be close to or away from each other. The ink supply port 41 and the ink discharge port 42 are arranged in a notch 45B formed in the upper end portion 45A. The flexible film 32 of the ink bag 34 is fixed to the inner surface of the cover plate 46, and the flexible film 32 faces outward as the pressure of the ink stored in the ink storage portion 33 varies. To be deformed. In the damper mechanism 31, the cover member 45 restricts the flexible film 32 from being deformed outward beyond the set value in accordance with the ink pressure fluctuation, so that the ink pressure fluctuates greatly. However, the effect that the flexible film 32 can be held in a stable shape is obtained.

(2) In the spring member 35, the two plate members 39 are coupled by the elastic member 40 so as to be elastically deformed so as to be close to or away from each other. However, the present invention is not limited to this, and FIG. 11 and FIG. As shown in (C), these two plate members 39 may be connected together via a connecting piece 44. Even with such a plate member 39 and the connecting piece 44, even if the capacity of the ink reservoir 33 changes according to the ink pressure, and the flexible film 32 of the ink bag 34 expands or contracts accordingly. The shape change of the flexible film 32 is regulated by the elastic force of the connecting piece 44, and the ink bag 34 can be maintained in a constant shape. That is, the elastic force of the connecting piece 44 restricts the flexible film 32 from being deformed more than a set value in accordance with the ink pressure fluctuation, so that the ink pressure is on the plus side (the state shown in FIG. 12A). ) Or the negative side (the state shown in FIG. 12C), the spring member 35 suppresses excessive deformation of the flexible film 32 and makes the flexible film 32 into a stable shape. Can be held.
Further, in the present embodiment, since the connecting piece 44 is used instead of the elastic member 40, it is possible to increase the volume of fluctuation of the ink bag 34 toward the minus side, and to reduce the pressure fluctuation on the minus side. It can be absorbed effectively.

(3) The ink bag 34 is formed by laminating two flexible films 32. However, instead of such an ink bag, one cover plate (the cover plate 46 in FIG. 13) is interposed with a holding member. Alternatively, a single flexible film may be attached and a portion surrounded by the flexible film and the other cover plate may be used as an ink storage portion.

A perspective view showing the entire inkjet recording apparatus Perspective view showing recording head block It is a figure which shows 1st Embodiment and is a perspective view which shows the damper mechanism of the state which opened the cover of the casing The perspective view which shows the ink bag accommodated in the cover member It is a figure which shows 2nd Embodiment and is a perspective view which shows the state in which the spring member was accommodated in the ink bag. (A) Plan view showing the ink bag, (B) Plan view showing the ink bag and the spring member accommodated in the ink bag The perspective view which shows the spring member of FIG. 5, FIG. FIG. 7 is a front sectional view taken along the line IIX-IIX in FIG. 6 showing a state in which the spring member is elastically deformed, and FIG. (B) is a diagram showing a plate member in a steady state, (C) is a diagram showing a state in which the plate members are close to each other due to a drop in ink pressure in the ink reservoir. The perspective view which shows the state in which the ink supply port and the ink discharge port were both provided in the upper end part of the ink bag A perspective view of the three sides of the ink bag with a gusset shape The perspective view which shows the state which replaced with the elastic member and connected the plate member using the connection piece. FIGS. 11A and 11B are front sectional views taken along line XII-XII in FIG. 11, in which FIG. 11A shows a state in which the ink pressure in the ink reservoir increases and the plate members are separated from each other, and FIG. The figure which shows a member, (C) is a figure which shows the state which the ink pressure in an ink storage part falls and a plate member adjoined mutually The perspective view which shows the damper mechanism which accommodated the ink bag formed in the cover member in the shape of a gusset

Explanation of symbols

1 Recording head block 3 Ink tank 4 Ink tube (ink supply path)
DESCRIPTION OF SYMBOLS 10 Inkjet recording head 11 Carriage 13 Damper mechanism 16 Ink storage part 17 Ink bag 18 Cover member 19 Flexible film 20 Ink supply port 21 Ink discharge port 30 Inkjet recording head 31 Damper mechanism 32 Flexible film 33 Ink storage part 34 Ink Bag 35 Spring member 37 Ink supply port 38 Ink discharge port 39 Plate member 41 Ink supply port 42 Ink discharge port 43 Gazette 45 Cover member

Claims (8)

An ink jet recording head that prints on a recording material by discharging ink supplied through an ink supply path from a nozzle hole,
In the middle of the ink supply path, a damper mechanism for absorbing pressure fluctuations of the ink is provided,
The damper mechanism includes an ink supply port that guides ink supplied from an ink tank to an internal ink storage portion, and an ink discharge port that discharges ink in the ink storage portion toward a nozzle hole. The storage portion is formed of a plurality of films.   The ink jet recording head according to claim 1, wherein the ink discharge port is disposed at an upper end portion in a vertical direction of the ink storage portion.   The damper mechanism includes a plurality of flexible films in which an ink storage portion is formed, and the flexible film that is accommodated in the flexible film and that changes in accordance with pressure fluctuations of ink stored in the ink storage portion. The inkjet recording head according to claim 1, further comprising: a spring member that restricts the property film from being deformed by a predetermined value or more.   The damper mechanism includes a plurality of flexible films in which an ink storage portion is formed, and the flexible film that accompanies a change in pressure of ink stored in the ink storage portion. The inkjet recording head according to claim 1, further comprising: a cover member that restricts the property film from being deformed outward by a predetermined value or more.   The inkjet recording head according to claim 3 or 4, wherein the plurality of flexible films are formed in a bag shape, and a peripheral portion of the bag body is formed in a gusset shape.   6. The ink jet recording head according to claim 5, wherein both the ink supply port and the ink discharge port are provided at an upper end in a vertical direction of the flexible film formed in the bag shape.   The inkjet recording head according to claim 1, wherein the damper mechanism is attached to the recording head.   An ink jet recording apparatus on which the ink jet recording head according to claim 1 is mounted.

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