JP2012056180A - Liquid discharge head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce variation in flow resistance by reducing the width of a liquid discharge head in the main scanning direction and aligning the length of a flow path connected to each storage section in an off-carriage liquid discharge apparatus.
A liquid storage chamber includes a first liquid storage chamber and a second liquid storage chamber in which a distance between the connection surface in a direction intersecting the connection surface is longer than that of the first liquid storage chamber. is there. The first liquid storage chamber and the second liquid storage chamber at least partially overlap each other in the intersecting direction. The flow path includes a first flow path connected to the first liquid storage chamber and a second flow path connected to the second liquid storage chamber. The length of the first flow path in the intersecting direction is shorter than the length of the second flow path in the intersecting direction, and the length in the direction along the connection surface of the first flow path is the second flow path. Longer than the length in the direction along the road.
[Selection] Figure 2

Description

  The present invention relates to a liquid discharge head that discharges liquid.

  In a typical ink jet recording apparatus as a liquid ejecting apparatus, a large-capacity ink tank may be employed in order to reduce the frequency with which the user replaces the ink tank. When a large-capacity ink tank is mounted on a carriage together with an ink jet head (liquid ejection head) (on-carriage method), since the weight applied to the carriage becomes heavy, the speed of the carriage may be reduced, leading to a reduction in throughput. There is. For this reason, an off-carriage ink jet recording apparatus (Patent Document 1) in which a large-capacity ink tank is not mounted on the carriage has been proposed. In the off-carriage method, ink is supplied from a large-capacity ink tank to an ink discharge portion of the ink-jet head through a sub-tank mounted on the carriage together with the ink-jet head and having a smaller capacity than the large-capacity ink tank.

Japanese Patent No. 3606282

  However, as described in Patent Document 1, when the sub tanks are arranged in parallel along the main scanning direction, which is the direction in which the carriage is scanned, the width of the ink jet head in the main scanning direction becomes large. There is a risk of increasing the size of the recording device.

  Therefore, in order to reduce the width of the inkjet head in the main scanning direction, a recording medium conveyance direction that intersects the main scanning direction in a tank (storage chamber) that independently stores ink in one sub-tank. A plurality of means can be considered. However, when the direction intersecting the main scanning direction is a direction intersecting the connection surface on which the connection portion of the ink flow path between the ink jet head and the ink jet recording apparatus is arranged, the following problems occur. That is, the length of the flow path provided inside the ink jet head for supplying ink from the ink jet recording apparatus main body to the sub tank varies, and the flow resistance in the flow path differs. Then, in the suction operation performed to improve the ink discharge characteristics of the inkjet head, if the suction conditions are matched with the long flow path, extra ink is consumed from the tank connected to the short flow path. .

  Accordingly, the present invention provides a liquid ejection apparatus of an off-carriage type in which the width of the liquid ejection head in the main scanning direction is reduced, and the lengths of the flow paths connected to the liquid storage chambers are made uniform, thereby causing variations in flow resistance. The purpose is to reduce.

  The liquid discharge head according to the present invention is a liquid discharge head for discharging a liquid, wherein a plurality of liquid storage chambers for storing liquid, which are arranged in parallel in a direction in which the liquid discharge head is scanned, and the liquid discharge head A flow path connected to a liquid supply section for supplying liquid to the liquid, and a connection section connected to the liquid supply section and the flow path, and a connection surface arranged along the scanned direction. The liquid storage chamber has a distance between the first liquid storage chamber and the connection surface with respect to a direction intersecting the connection surface, and a direction intersecting the connection surface and the first liquid storage chamber. A second liquid storage chamber that is long compared to the distance with respect to the first liquid storage chamber and the second liquid storage chamber, and at least part of the first liquid storage chamber and the second liquid storage chamber overlap each other in the intersecting direction, In the channel, the first liquid storage chamber There is a first flow path that is continued and a second flow path that is connected to the second liquid storage chamber, and the length of the first flow path in the intersecting direction is the second flow path. The length of the first flow path in the direction along the connection surface is shorter than the length in the intersecting direction, and the length of the first flow path in the direction along the connection surface is longer than the length of the second flow path in the direction along the direction. It is characterized by.

  According to the present invention, in the off-carriage type liquid discharge apparatus, the width of the liquid discharge head in the main scanning direction is reduced, and the lengths of the flow paths connected to the respective storage portions are made uniform to reduce variations in flow resistance. It becomes possible.

1 is a partial perspective view of an ink jet recording apparatus equipped with an ink jet head to which the present invention can be applied. 1 is an exploded perspective view showing an inkjet head to which the present invention can be applied and a part of a carriage connected to the inkjet head. It is a figure which shows a sub tank. It is a figure which shows a joint part and a joint part flow path.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a part of an ink jet recording apparatus as a liquid ejection apparatus to which the present invention can be applied. An ink jet recording apparatus according to an embodiment to which the present invention is applicable performs printing with 12 colors of ink. The ink jet recording apparatus includes an ink jet head 1000 as a liquid discharge head for discharging a liquid, a carriage 4000, a main tank 2000, and an ink supply path 3000.

  The inkjet head 1000 is detachably mounted on the carriage 4000, the carriage 4000 is reciprocally scanned, and the inkjet head 1000 ejects ink, thereby printing on a recording medium.

  The main tank 2000 stores inks of different colors, and is arranged at a place other than the carriage 4000. The ink supply path 3000 is configured by a flexible tube, and communicates the main tank 2000 and the inkjet head 1000 to supply ink to the inkjet head 1000.

  FIG. 2 is an exploded perspective view showing the ink jet head 1000 and the joint surface of the carriage 4000 connected to the ink jet head 1000.

  Joint needles 4001 (liquid supply units) for supplying ink to the inkjet head 1000 are provided on the joint surface on the carriage 4000 side for the number of colors of ink. Joint needles 4001 are respectively inserted into joint portions 5002 (connection portions) that are openings provided on a joint surface 5001 (connection surface) on the inkjet head 1000 side. Thereby, the inkjet head 1000 and the main tank 2000 are communicated with each other via the ink supply path 3000.

  The needle seal 5005 is disposed in the joint portion 5002 and prevents leakage of ink from the joint portion 5002 by closing the space generated by the difference in diameter when the joint needle 4001 is inserted into the joint surface 5001. A joint cover 5006 attached to the joint surface 5001 so as to cover the needle seal 5005 from the outside fixes the needle seal 5005 in the joint portion 5002.

  The ink supplied to the inkjet head 1000 via the joint unit 5002 is temporarily stored in a sub tank 6000 provided on the inkjet head 1000, and then supplied to an ink discharge unit (not shown) of the inkjet head. Further, during distribution, the sub tank 6000 is filled with distribution ink. Accordingly, the joint film 5007 is welded so as to surround each joint hole of the joint cover 5006, thereby preventing the distribution ink from leaking out from the joint portion 5002.

  FIG. 3A shows a perspective view of the sub tank 6000, and FIG. 3B shows a top view of the sub tank 6000 when the side connected to the ink discharge section is the lower surface.

  In the present embodiment, since one sub tank 6000 is provided with a first ink storage chamber 6002a, a second ink storage chamber 6002b, and two ink storage chambers (liquid storage chambers), one sub tank 6000 is provided. Two colors of ink can be stored. In order to supply 12 colors of ink to the ink discharge section, the inkjet head 1000 is provided with six sub tanks 6000. As shown in FIG. 2, the sub tanks 6000 are arranged in parallel in the main scanning direction of the carriage 4000. Therefore, the first ink storage chamber 6002a and the second ink storage chamber 6002b are provided so as to overlap each other when viewed from the direction intersecting the joint surface (the vertical direction in the present embodiment).

  With this configuration, one ink storage chamber is provided in one sub tank, and the dimensions of the ink jet head 1000 in the main scanning direction are compared with the configuration in which the sub tank is arranged in parallel in the main scanning direction (x direction) of the carriage 4000. Can be narrowed. As a result, the ink jet recording apparatus can be miniaturized. In this embodiment, two ink storage chambers are provided in one sub tank, but three or more ink storage chambers may be provided.

  The ink supplied into the ink jet head 1000 passes through a joint portion channel 5003 formed inside a joint surface 5001 which will be described in detail later, and passes from the first ink inlet 6003a or the second ink inlet 6003b to the sub tank. 6000 is supplied. The ink supplied from the first ink inlet 6003a passes through the first sub tank channel 6001a formed in the sub tank 6000 and is supplied to the first ink storage chamber 6002a. Further, the ink supplied from the second ink inlet 6003b passes through the second sub tank channel 6001b formed in the sub tank 6000 and is supplied to the second ink storage chamber 6002b.

  Here, the distance between the first ink storage chamber 6002a and the joint surface 5001 in the direction intersecting the joint surface (the y direction in FIG. 3A) corresponds to that of the second ink storage chamber 6002b. It is shorter than the distance. Accordingly, the length L1 of the first sub tank channel 6001a and the length L2 of the second sub tank channel 6001b are in a relationship of L1 <L2.

  4A is a diagram showing a joint surface 5001 of the inkjet head 1000, and FIG. 4B is a diagram of the inkjet head 1000 in a state in which the sub tank 6000 is not attached, taken along line AA shown in FIG. It is sectional drawing.

  The joint surface 5001 is provided with twelve joint portions 5002 corresponding to the number of ink colors, and two positioning pin holes 5004 for positioning the joint portion 5002 and the joint needle 4001.

  In the joint surface 5001, adjacent joint portions 5002 are shifted in the height direction (z direction) so that the twelve joint portions 5002 do not overlap, and the joint portions 5002 are arranged in a staggered manner in two upper and lower rows. Yes. Here, in the state in which the inkjet head 1000 is used, the joint portion 5002 positioned below in the height direction is the first joint portion 5002a, and the joint portion 5002 positioned above is the second joint portion 5002b. .

  As shown in FIG. 4B, a joint portion channel 5003 is formed inside the joint surface 5001 in the direction along the joint surface 5001. The joint part channel 5003 includes a first joint part channel 5003a connected to the first joint part 5002a and a second joint part channel 5003b connected to the second joint part 5002b. Accordingly, the length d1 of the first joint portion channel 5003a and d2 of the second joint portion channel 5003b are in a relationship of d1> d2.

  Therefore, the first joint flow channel 5003a having a long length is connected to the first ink inlet 6003a for supplying ink to the first sub tank flow channel 6001a having a short length. On the other hand, the second joint flow channel 5003b having a long length is connected to the second ink inlet 6003b for supplying ink to the second sub tank flow channel 6001b having a long length.

  Therefore, the length of the first flow path combining the first sub-tank flow path 6001a and the first joint section flow path 5003a is combined with the second sub-tank flow path 6001b and the second joint section flow path 5003b. Further, the lengths of the second flow paths can be made as uniform as possible. That is, the lengths of the flow paths from the joint portion 5002 to the ink storage chamber 6002 can be made uniform, and variations in flow resistance can be reduced. This makes it possible to make uniform the conditions during the suction operation for the plurality of flow paths.

  With the above configuration, in the off-carriage type ink jet recording apparatus, the widths of the ink jet head and the ink jet recording apparatus in the main scanning direction can be reduced while aligning the lengths of the plurality of flow paths as much as possible.

1000 Inkjet head (liquid discharge head)
4001 Joint needle (liquid supply part)
5001 Joint surface (connection surface)
5002 Joint part (connection part)
5003a First joint part flow path 5003b Second joint part flow path 6000 Sub tank 6001a First sub tank flow path 6001b Second sub tank flow path 6002a First ink storage chamber (first liquid storage chamber)
6002b Second ink storage chamber (second liquid storage chamber)

Claims (3)

A liquid discharge head for discharging liquid,
A plurality of liquid storage chambers for storing liquid, which are arranged in parallel in a direction in which the liquid discharge head is scanned;
A flow path connected to a liquid supply unit for supplying a liquid to the liquid discharge head;
A connection portion connected to the liquid supply portion and the flow path, and a connection surface disposed along the scanned direction;
Have
In the liquid storage chamber, the distance between the first liquid storage chamber and the connection surface with respect to the direction intersecting the connection surface is the distance between the connection surface and the first liquid storage chamber with respect to the intersecting direction. The first liquid storage chamber and the second liquid storage chamber are at least partially overlapping with each other in the intersecting direction,
The flow path includes a first flow path connected to the first liquid storage chamber and a second flow path connected to the second liquid storage chamber.
The length of the first flow path in the intersecting direction is shorter than the length of the second flow path in the intersecting direction, and the length of the first flow path in the direction along the connection surface. Is longer than the length of the second flow path in the direction along the line. The connection portion includes a first connection portion connected to the first flow path, and a second connection portion connected to the second flow path,
2. The liquid discharge head according to claim 1, wherein the first connection portion is provided below the second connection portion in a state in which the liquid discharge head is used.   The plurality of first connection portions and the plurality of second connection portions are arranged on the connection surface in a staggered manner with respect to a direction intersecting the discharge direction. Item 3. The liquid discharge head according to Item 2.

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