JP2001310484A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet printer capable of withstanding high ink supply quantity and long time use required for increasing the size and supplying ink depending on a variety of use quantities of ink without increasing the manufacturing cost, external dimensions and weight proportionally. SOLUTION: In the ink jet printer, a pump unit 32a included in an ink supply unit 16 provided in an ink supply tube 14K from an ink tank to an ink jet head comprises a pump body 34K including a cylinder 48K provided with an ink suction hole 44K and an ink ejection hole 46K, and a piston 50K capable of reciprocating in the cylinder, and a piston drive mechanism 42K for reciprocating the piston of the pump body in the cylinder through movement of a press pin 38a incident to rotation in any one direction of a rotator 38 rotatable selectively in two directions through a motor 30 and provided with the press pin spaced apart from the center of rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an ink jet printer.

[0002]

2. Description of the Related Art Conventionally, ink jet printers have been widely used as printers for personal computers.
The ink jet printer has an advantage that it is easy to record a full-color image with full color and is inexpensive.

For this reason, recently, large-sized ink jet printers capable of recording full-color images on large sheets such as A1 and A0 plates and a continuous web of these large sheets have appeared. The material of a sheet or a web on which an image is recorded by such an ink jet printer is not limited to paper, but also spreads to plastic films and cloths.

[0004] Naturally, a large ink jet printer consumes a large amount of ink, and therefore the ink tank is also large. The large and heavy ink tank is disposed apart from the ink jet head, and ink is supplied from the ink tank to the ink jet head by an ink supply unit including a motor and a pump unit driven by the motor.

[0005] Such an ink supply unit is disclosed, for example, in JP-A-11-138841. In this conventional ink supply unit, ink is supplied from an ink tank to an inkjet head using a so-called tube pump.

Further, in an ink jet printer, as the type of ink used increases, the gradation of an image recorded by the ink jet printer becomes rich.
In recent years, the number of types of ink used has been increasing.

[0007]

As the types of inks used increase, the number of ink supply units used increases, resulting in an increase in the manufacturing cost of an ink jet printer and an increase in external dimensions and weight. The use of the above-described tube pump contributes to a reduction in manufacturing cost, but has a short life when used in a large-sized ink jet printer which requires a large ink supply amount and a long time use.

SUMMARY OF THE INVENTION The present invention has been made under the above circumstances, and an object of the present invention is to provide a large ink supply printer which can withstand a large ink supply amount and a long time use which are required for a long period of time. Even if the number of types of ink increases, it is possible to supply ink according to the usage amount of each type of ink, but the manufacturing cost increases and the external dimensions are proportional to the number of types of ink used. An object of the present invention is to provide an ink jet printer which does not cause an increase in weight or weight.

[0009]

In order to achieve the object of the present invention as described above, an ink jet printer according to the present invention comprises: an ink jet head; an ink tank containing ink; an ink tank and an ink jet head. And an ink supply unit provided in the ink supply tube for supplying ink from an ink tank to the inkjet head. The ink supply unit comprises: a motor; A pump unit driven by a motor, the pump unit comprising:
A cylinder provided with an ink suction hole communicated with the ink tank by the ink supply tube and an ink discharge hole communicated with the ink jet head by the ink supply tube, a piston reciprocable in the cylinder, A rotating body, which is selectively rotatable in two directions by the motor, and is provided with a pressing pin at a position distant from the center of rotation, and a rotating body in any one of the rotating bodies. A piston drive mechanism for driving the piston of the pump body in the cylinder by movement of the pressing pin.

[0010] In the ink jet printer according to the present invention having the above-described structure, the pump body of the pump unit driven by the motor of the ink supply unit is connected to the ink tank by the ink supply pipe. It has a cylinder provided with a suction hole and an ink ejection hole communicated with the ink jet head by an ink supply pipe, and a piston that can reciprocate in the cylinder, so that a large ink supply amount required by a large ink jet printer can be obtained. It can withstand long-term use for a long time.

Further, the pump body can be selectively rotated in two directions by a motor, and the pressing body is moved by one of the rotating members provided with the pressing pin at a position distant from the center of rotation. The piston drive mechanism that reciprocates the piston in the cylinder can control the supply of desired ink by selecting the rotation direction of the output shaft of the motor.

[0012] In the ink jet printer according to the present invention, which is configured as described above, as described above, the pump unit has a pair of pump bodies and a pair of piston driving mechanisms. One piston drive mechanism drives the piston of one of the pump bodies in the cylinder by the movement of the pressing pin due to the rotation of the rotating body in one direction, and the rotation of the rotating body in the other direction. The other piston drive mechanism drives the piston of the other pump body in the cylinder by the movement of the pressing pin due to the rotation.

When the ink supply unit of the ink jet printer according to the present invention is used to supply a plurality of types of ink to a plurality of ink jet heads,
The ink jet printer according to the present invention can be expressed as follows.

An ink-jet head; an ink tank containing ink; an ink supply pipe connecting the ink tank and the ink-jet head; and an ink provided in the ink supply pipe for supplying ink from the ink tank to the ink-jet head. A supply unit; wherein the ink supply unit includes one motor and a plurality of pump units selectively driven by the motor, wherein the plurality of pump units are: A cylinder provided with an ink suction hole communicated with the ink tank by the ink supply tube and an ink discharge hole communicated with the ink jet head by the ink supply tube, a piston reciprocable in the cylinder, A plurality of pump bodies each having A plurality of gears rotated by two motors, a plurality of rotating bodies each of which is rotatable in two directions and is provided with a pressing pin at a position separated from a center of rotation, the plurality of gears and the plurality of rotating bodies A plurality of clutches interposed between the plurality of gears and selectively transmitting a rotational driving force from the plurality of gears to the plurality of rotating bodies; and a plurality of clutches selectively rotating driving force from the corresponding plurality of gears. And a plurality of piston drive mechanisms for driving the pistons of the plurality of pump bodies in the cylinder by movement of the pressing pins accompanying rotation of the plurality of rotating bodies in any one direction. It is characterized by that.

In the ink jet printer according to the present invention having the above-described structure, a plurality of gears and a plurality of gears described later, which select a rotation direction of a motor and transmit a rotational driving force from the motor, are provided. The use of a combined clutch allows for selective actuation of the pistons of multiple pump bodies by using only one motor. For this reason, even if the type of ink used increases, it is possible to supply the ink according to the usage amount of each type of ink, but the manufacturing is proportional to the increase of the type of ink used. There is no increase in cost and external dimensions and weight.

Hereinafter, an ink jet printer according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, FIG.
The configuration of the inkjet printer according to the embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 1 is a schematic perspective view of a main part of an ink-jet printer according to an embodiment of the present invention; FIG. 2 is a diagram showing ink supply of the main part in the ink-jet printer of FIG. FIG. 3 is a schematic horizontal sectional view of the ink supply unit of the main part in the ink jet printer of FIG. 1; FIG. 4 is a view showing the main part of the ink jet printer of FIG. FIG. 5A is a schematic cross-sectional view of an ink supply unit; FIG. 5A is a schematic vertical cross-sectional view of a sub ink tank of the main part in the ink jet printer of FIG. 1; FIG. 6 is a schematic side view of the sub-ink tank of FIG.
FIG. 6 is a diagram schematically showing a configuration of an ink supply control system in the inkjet printer of FIG.

As shown in FIGS. 1 and 2, an ink jet printer according to an embodiment of the present invention has six ink jet heads 10K, 10C and 10C.
M, 10LC, 10LM, and 10Y, and six ink bottles 12K, 12C, 12M, 12LC, and 12 serving as main ink tanks each containing six types of ink.
LM, 12Y and ink bottles 12K, 12C, 12
M, 12LC, 12LM, 12Y and inkjet heads 10K, 10C, 10M, 10LC, 10LM, 10
Y and six ink supply pipes 14K, 14C, 1
4M, 14LC, 14LM, 14Y, and ink supply pipes 14K, 14C, 14M, 14LC, 14LM, 1
4Y, each ink bottle 12K, 12K
Inkjet heads 10K, 10C, 10M, 10L corresponding to C, 12M, 12LC, 12LM, 12Y
C, 10LM, and 10Y.

The ink bottles 12K, 12K
The types of ink contained in C, 12M, 12LC, 12LM, and 12Y are black, cyan, magenta, light cyan, light magenta, and yellow, respectively.

Hereinafter, for convenience, the six ink jet heads are collectively referred to simply as “ink jet head 10”, the six ink bottles are collectively referred to simply as “ink bottle 12”,
The six ink supply pipes are collectively referred to simply as “ink supply pipe 1”.
4 ".

The ink-jet heads 10 have the same structure, the ink bottles 12 have the same structure, and the ink supply tubes 14 have the same structure. The ink bottle 12 is detachable from the ink supply pipe 14, and can be easily replaced with a new ink bottle 12 when the stored ink runs out.

The ink jet head 10 includes the carriage 1
8 in a predetermined arrangement. The carriage 18 is moved along two guide rods 20 extending in the main scanning direction by arrows X.
Can be reciprocated in the main scanning direction, as shown by, and is reciprocated at a predetermined speed along a predetermined range along the guide rod 20 by well-known reciprocating drive means (not shown).

The ink bottle 12 is not mounted on the carriage 18 but is held below a fixed frame (not shown) in order to stabilize the ink jet printer of this embodiment and to increase the reciprocating speed of the carriage 18. ing.

The sub-ink tanks 21K, 21C, and 21 having a much smaller capacity than the ink bottle 12 are provided on the carriage 18 adjacent to the ink-jet heads 10, respectively.
M, 21LC, 21LM, and 21Y (hereinafter, also collectively referred to as “sub ink tank 21”) are also mounted. From the ink supply unit 16 to the ink supply pipe 14
The ink supplied to the ink-jet head 10 is temporarily stored in the sub-ink tank 21 and then ejected from the ink-jet head 10.

In each of the ink supply pipes 14 between each of the ink bottles 12 and the ink supply unit 16, a check valve 17a for preventing the ink from flowing back from the ink supply unit 16 to each of the ink bottles 12 is provided. And the ink supply unit 16 and the sub ink tank 21
A check valve 17b for preventing backflow of ink from the sub ink tank 21 to the ink supply unit 16 is interposed between the check valve 17b and the ink supply unit 16.

In the ink jet printer according to this embodiment, an elongated web-shaped recording medium 22 having a predetermined width is arranged so as to face in parallel to the reciprocating locus of the ink jet head 10. A direction (sub-scanning direction) Y orthogonal to a reciprocating direction (main scanning direction) X of the carriage 18 by the plurality of transport rollers 24.
, A predetermined width is conveyed each time the carriage 18 moves.

The back surface of the recording medium 22 facing the reciprocating locus of the ink jet head 10 is supported by a flat platen 26 parallel to the reciprocating locus.

The ink supply pipe 14 has a length sufficient to allow free reciprocation of the ink jet head 10 in accordance with reciprocation of the carriage 18 in the main scanning direction X, and has flexibility. Have.

In the ink jet printer of this embodiment, when image forming data is input to the ink jet printer, the recording medium 22 intermittently moves a predetermined distance each time the carriage 18 moves forward and backward in the main scanning direction X. The ink of the type selected in a pattern based on the image forming data while the inkjet head 10 is moving forward and backward with respect to the recording medium 22 temporarily transported and temporarily stopped on the platen 26 during this time. Is ejected to form an image based on the image forming data.

The material of the recording medium 22 may be any material as long as an image can be formed by ejecting ink from a plurality of ink jet heads 10, such as paper, coated paper, plastic film, and cloth.

Next, the configuration of the ink supply unit 16 of the ink jet printer according to one embodiment of the present invention will be described in detail with reference to FIGS.

The ink supply unit 16 includes one motor 30 and three pump units 32a, 32b, and 32c that are selectively driven by the motor 30 and have the same configuration.
And

The first pump unit 32a includes a pair of pump bodies 34K and 34Y for symmetrically arranged black ink and yellow ink, and the second pump unit 32b is symmetrically arranged. A pair of pump bodies 34 for cyan ink and light magenta ink
C, 34LM, and a third pump unit 32c includes a pair of pump bodies 34M, 34 for symmetrically disposed magenta and light cyan inks.
Contains LC.

A pair of pump bodies 34K and 34Y of the first pump unit 32a and a second pump unit 32b
And a pair of pump bodies 34M, 34 of the third pump unit 32c.
Since LC and LC have the same configuration,
The first pump unit 32a will be mainly described, and the remaining second and third pump units 32b, 32
The explanation of c is omitted.

The pump unit 32a includes a gear 36a provided on the substrate 35 so as to be rotatable in two directions between a pair of pump bodies 34K and 34Y arranged symmetrically, and a pair of pump bodies 34K and 34Y. A rotating body 37a provided on the substrate 35 coaxially with the gear 36a and rotatable in two directions and having three pressing pins 38a at equal intervals on a concentric circle separated from the center of rotation; The rotating body 37a is interposed between the rotating body 37a and the gear 36a.
A clutch 40a for selectively transmitting the rotational driving force to
The movement of the pressing pin 38a when the rotating body 37a rotates in one direction drives only one of the pair of pump bodies 34K and 34Y, and the movement of the pressing pin 38a when the rotating body 37a rotates in the other direction. A pair of pump bodies 34
K, 34Y (hereinafter referred to as a first pump unit 32a
In the same components corresponding to those in the second pump unit 32b, the K and Y given to the reference numerals are displayed instead of C and LM, and Corresponding identical components in the pump unit 32c are denoted by reference numerals with K and Y replaced by M and LC.
To be displayed instead of).

The gear 36a of the first pump unit 32a and the gear and the rotating body of the second pump unit 32b corresponding to the rotating body 37a are denoted by reference numerals 36b and 36b, respectively.
37b, the gear 36a of the first pump unit 32a, the gear and the rotating body of the third pump unit 32c corresponding to the rotating body 37a, respectively, are designated by reference numerals 36c, 37c. .

Each of the pair of pump bodies 34K and 34Y has the same configuration as each other, and the ink supply pipes 14K and 14Y
Y, ink suction holes 44K, 44Y connected to the ink bottles 12K, 12Y, and ink supply pipes 14K,
Cylinders 48K, 48Y having ink ejection holes 46K, 46Y connected to the inkjet heads 10K, 10Y by 14Y, and cylinders 48K, 48Y.
And pistons 50K and 50Y that can reciprocate along the center line of the cylinder 48 therein.

The gears 36a, 36b, and 36c have the same external dimensions and the same number of teeth, and the gears 36a and 36b mesh with each other, and the gears 36b and 36c mesh with each other. The fixed output gear 30a is further meshed with the gear 36a.

A pulse plate driving gear 51 rotatably supported by the substrate 35 is meshed with the gear 36a of the pump unit 32a.
, A pulse plate 52 is coaxially fixed. The pulse plate 52 is combined with a photo interrupter 54, and the number of rotations of the gear 36a can be known by the combination of the pulse plate 52 and the photo interrupter 54.
The number of teeth of the pulse plate driving gear 51 is the same as that of the gear 36a, and the rotation ratio is 1: 1. The pulse plate 52 is provided with 15 light-shielding arms radially. Therefore, the photo interrupter 54 detects 15 pulses when the gear 36a makes one rotation.

A pair of piston drive mechanisms 42K, 42Y
Is interposed between a corresponding pair of pump bodies 34K and 34Y and a corresponding one gear 36a and one rotating body 37a, and is a straight line connecting the rotation centers of the three gears 36a, 36b and 36c (FIG. 3, a line extending vertically). Although the pair of piston drive mechanisms 42K and 42Y are arranged symmetrically on the substrate 35 but have basically the same configuration, the configuration of the piston drive mechanism 42K will be described below. The description of the drive mechanism 42Y is omitted.

The piston drive mechanism 42K includes a gear 36a and a rotating body 37a corresponding to the pump body 34K on the substrate 35.
Between the rotation center shaft 56K and the rotation center of the gear 36a and the rotating body 37a. It has a rotation restricting projection 58K provided at a position closer to the gear 36a and the rotating body 37a than the center shaft 56K.

The piston drive mechanism 42K also has a
Above corresponding pump body 34K and corresponding gear 36a
A piston pressing member 60K is provided between the piston pressing member 60K and the rotating body 37a. The piston pressing member 60K includes a corresponding pump body 34K, a corresponding gear 36a, and a rotating body 37.
A movement restricting hole 62K extending toward “a” is formed, and the movement restricting hole 62K is rotatably and slidably fitted on the rotation center shaft 56K.

The piston drive mechanism 42K further includes a biasing means 64K between the piston pressing member 60K and the rotation restricting projection 58K, and pulls the piston pressing member 60K toward the rotation restricting projection 58K, and the corresponding pump body. Attracts away from 34K. In this embodiment, the urging means 64K is constituted by a tension coil spring.

The pair of piston drive mechanisms 42K further urges the corresponding pump body 34K to bias the piston 50K away from the ink suction hole 44K and the ink discharge hole 46K to approach the piston pressing member 60K. It has means 66K. In this embodiment, the urging means 66K is constituted by a compression coil spring.

In the state shown in FIG.
Each of the three pressing pins 38a on 7a
The inner end (left end) IN of the pair of piston pressing members 60K and the inner end (right end) IN of the piston pressing member 60Y are not pressed, and the urging force of the corresponding urging means 64K is set by the piston pressing member 60K. The rotation restricting projection 58K is in contact with the rotation restricting projection 58K and the movement restricting hole 6
While the outer end (right end) of 2K is in contact, the outer edge of the piston pressing member 60K presses the piston 50K in the pump body 34K against the urging force of the urging means 66K. Absent. The position when the piston 50K is located at the leftmost position in the figure is called a home position.

As is apparent from FIG. 3, the inner edge IN of the piston pressing member 60K is formed such that the side (lower side) of the piston pressing member 60K on the rotation restricting protrusion 58K side is the rotation restricting protrusion 5.
8K, the three gears 36a, 36b,
36c is configured to be inclined with respect to a straight line connecting the respective rotation centers. Further, the intersection area between the inner edge IN and the corresponding side on the rotation regulating protrusion 58K side is rounded.

Next, the configuration of the sub ink tank 21K will be described in detail with reference to FIGS. 5A and 5B. The remaining sub ink tanks 21C, 21M,
Each of 21LC, 21LM, and 21Y has the same configuration as the sub ink tank 21K shown in FIGS. 5A and 5B, and a description thereof will be omitted.

The sub ink tank 21K is
0 has an ink supply hole 72 at the upper end. The ink supply hole 72 is connected to an ink supply pipe 14K via the ink supply unit 16 from the corresponding ink bottle 12K. A filter 74 for removing foreign matter in the ink is provided in the middle of the internal space of the housing 70.

A surplus ink discharge hole 76 and an air opening hole 78 are provided above the filter 74 in the internal space of the housing 70, and the surplus ink discharge hole 76 has flexibility similarly to the ink supply pipe 14K. A flexible surplus ink discharge pipe 80 communicates with a waste ink tank (not shown). The waste ink tank is removably mounted on the above-mentioned fixed frame (not shown) of the ink jet printer of this embodiment. The atmosphere opening hole 78 is disposed above the surplus ink discharge hole 76.

A float 82 is arranged below the filter 74 in the interior space of the housing 70. The float 82 can swing up and down around a rotation center shaft 82a at one end, and the float 82 swings up and down in accordance with the amount of ink stored below the filter 74. In FIG. 5A, the ink level at the ideal ink storage amount of the sub ink tank 21K is indicated by reference numeral ILV, and the float 82 at that time is shown.

The sub ink tank 21K is provided with an ink amount detecting device 84 for detecting the presence or absence of a predetermined amount of ink below the filter 74 in the internal space of the sub ink tank 21K. In this embodiment, the ink amount detecting device 84 is configured to
A magnet 84a provided at the other end remote from 2a and a first magnet detection disposed at a position corresponding to the magnet 84a of the float 82 when the float 82 is disposed at the lower end position on the outer surface of the housing 70. (I.e., a low-level ink detector) 86a and a second position on the outer surface of the housing 70 corresponding to the magnet 84a at the other end of the float 82 when the float 82 is positioned at the upper end position. And a second magnet detector (that is, an ink high level detector) 86b.

In the internal space of the sub-ink tank 21K, an ink discharge pipe 88 extends from below the filter 74 to the outside of the housing 70.
Is connected to an ink supply pipe 14K extending to the corresponding inkjet head 10K.

In this embodiment, the sub ink tanks 21K, 21C, 21M, 21LC, 21LM, 21
The corresponding ink supply pipes 14K, 14C, 14M, 14LC, 14LM, adjacent to the respective ink supply holes 72 of Y
14Y, sub ink tanks 21K, 21C, 21M, 21LC, 21L as shown in FIG.
Ink presence / absence detection means 90K, 90C, 90M, 90LC for detecting presence / absence of ink flowing into each of M, 21Y;
90LM and 90Y are provided. Ink presence detecting means 90K, 90C, 90M, 90LC, 90LM, 90
As Y, for example, a configuration utilizing a change in the amount of light transmission due to the presence or absence of ink can be considered.

Next, the configuration of the ink supply control system in the ink jet printer according to the embodiment of the present invention will be described in detail with reference to FIG.

In the ink supply control system of this ink jet printer, the photo interrupter 54, motors 30, 3 of the ink supply unit 16 shown in FIG.
The three clutches 40a, 40b, 40c of the three pump units 32a, 32b, 32c, and the six sub-ink tanks 21K, 21C, 21M, 21 shown in FIG.
Ink presence / absence detection means 90K, 90C, 90M, 90L adjacent to ink supply holes 72 of LC, 21LM, 21Y
C, 90LM, 90Y and an unillustrated exterior cover open / close detection means of the ink jet printer are connected to a controller CTL with a timer.

The above controller CTL is further provided with FIG.
Sub ink tank 2 for black ink shown inside
1K ink low level detector 86a and ink high level detector 86b, sub ink tank 21C for cyan ink, ink low level detector 86a and ink high level detector 86b, sub ink tank for magenta ink 21M ink low level detector 86a and ink high level detector 86b, sub-ink tank for light cyan ink 21LC ink low level detector 86a and ink high level detector 86b, sub-ink for light magenta ink Ink low level detector 86a and ink high level detector 86b of tank 21LM, and ink low level detector 86a and ink high level detector 86 of sub-ink tank 21Y for yellow ink
b, and the display device is connected.

In the ink jet printer according to one embodiment of the present invention, which is configured as described above, the controller CTL controls the motor 30 according to the signal output from each of the above-described ink level detectors.
And two or more of the three clutches 40a, 40b, and 40c are selected, and the six piston drive mechanisms 42K,
The desired one or more of 2C, 42M, 42LC, 42LM, and 42Y is assigned to a corresponding piston 50K, 50Y.
C, 50M, 50LC, 50LM, and 50Y are driven to be pressed. Then, the controller CTL can detect the number of rotations of each of the gears 36 and, consequently, the number of rotations of each of the rotating bodies 37 by the photointerrupter 54, thereby detecting the ink ejection amount of the driven pump body 34.

Next, with reference to FIGS. 7A, 7B, 7C and 7D, in the ink jet printer according to the embodiment of the present invention, one motor 30 of the ink supply unit 16 will be described. A pair of pump bodies 34 by the pair of piston drive mechanisms 42K and 42Y of the pump unit 32a when the output shaft is rotated in one direction.
How K and 34Y are driven or stopped will be described in detail.

In FIG. 7A, each of the three pressing pins 38a of the rotating body 37a is connected to a pair of piston driving mechanisms 42.
K, 42Y do not press the inner edge IN of the pair of piston pressing members 60K, 60Y, and therefore, the pair of piston pressing members 60K, 60Y also have a corresponding pair of pump bodies 34K, A home position state similar to FIG. 3 in which the 34Y pistons 50K and 50Y are not pressed is shown. The three pressing pins 38 of the rotating body 37a
a is a serial number 1 in the figure to clearly show the respective actions.
2, 3 are added.

First, the procedure for supplying only yellow ink will be described.

When the controller CTL is the sub ink tank 2
Upon detecting the signal from the 1Y ink low level detector 86a, the controller CTL rotates the motor 30 forward and selects and turns on the clutch 40a. Motor 3
When 0 rotates forward, the output gear 30a rotates clockwise in the figure at a predetermined rotation speed. When the clutch 40a is turned on, the rotating body 37a follows the rotation of the gear 36a.

Since the output gear 30a rotates clockwise, the gear 36a and the rotating body 37a rotate counterclockwise (in the direction indicated by arrow Y) in the figure.

In the rotation direction Y of the rotary plate 37a, the pressing pin 38a (serial number 2) which contacts the inner end IN of the piston pressing member 60Y corresponding to the pump body 34Y is shown in FIG.
As shown in (B), the inner edge IN is pressed. By this pressing, the piston pressing member 60Y approaches the piston 50Y of the pump body 34Y relatively to the rotation center shaft 56Y along the extending direction of the movement restriction hole 62Y in a state of being pressed by the rotation restriction protrusion 58Y. To move against the urging force of the urging means 64Y. By this movement, the outer edge (left edge) of the piston pressing member 60Y is moved to the pump body 3
The 4Y piston 50Y is pressed against the urging force of the urging means 66Y, and the ink in the cylinder 48Y is supplied from the ink discharge hole 46Y to the sub-ink tank 21Y through the ink supply pipe 14Y.
Extrude through Y.

When the rotation of the rotary plate 37a further continues as indicated by the arrow Y, the pressing pin 38a (serial number 2) moves between the inner edge IN of the piston pressing member 60Y and the side on the rotation restricting projection 58Y side. It passes through the rounded intersection area of the joint. For this reason, the piston pressing member 60Y uses the urging force of its own urging means 64Y to press the pressing pin 38a (serial number 2).
In contrast to when the inner edge IN is pressed, the side on the rotation restricting projection 58Y side is rotated along the extending direction of the movement restricting hole 62Y while being pressed by the rotation restricting projection 58Y. It moves relatively to the moving center shaft 56Y so as to be separated from the piston 50Y. The piston pressing member 60Y has the side on the rotation regulating protrusion 58Y side abutting on the rotation regulating protrusion 58Y as shown in FIG.
The outer edge is separated from the piston 50Y. With the return of the piston pressing member 60Y, the piston 50Y of the pump body 34Y also moves in the cylinder 48Y by the urging force of its own urging means 64Y as shown in FIG.
Move to the far right and return to the home position. When the piston 50Y returns to the home position, yellow ink from the ink bottle 12Y is sucked into the cylinder 48Y of the pump body 34Y from the ink suction hole 44Y via the ink supply pipe 14Y.

The rotating body 37a has three pressing pins 38a planted at equal intervals. The pulse plate 52 has 15 light-shielding arms. Further, the rotation ratio between the gear 36a and the pulse plate driving gear 51 is set to 1: 1.
From these relationships, when the rotator 37a makes one rotation, the photo interrupter 54 detects the pulse 15 times. When the rotating body 37a makes one rotation, the pressing pin 38a presses the piston pressing member 60K or 60Y three times,
The piston 50K or 50Y will be driven three times. Therefore, when the photo interrupter 54 detects the pulse five times, the rotating body 37a rotates １ ／, and the piston 50 is driven once. Piston 50
Since the amount of ink discharged when is driven once is substantially constant and is known in advance, the number of times the piston is driven and thus the amount of ink discharged can be detected by detecting the pulse of the photo interrupter 54.

On the other hand, in the piston pressing member 60K corresponding to the pump body 34K, the rotation restricting projection 58K
The pressing pin 38a (serial number 1) abutting on the side presses the side as shown in FIG. 7B. By this pressing, the piston pressing member 60K moves the movement restricting hole 6K.
When the outer end (right end) of 2K is in contact with the rotation center shaft 56K, the rotation center shaft 56K is opposed to the urging force of the urging means 64K.
It will rotate around. During this rotation, the outer edge of the piston pressing member 60K keeps separating from the piston 50K of the pump body 34K and does not press the piston 50K, so that the supply of black ink by the pump body 34K does not occur.

When the rotation of the rotary plate 37a further continues as indicated by the arrow Y, the pressing pin 38a (serial number) abutting on the side of the rotation restricting projection 58K in the piston pressing member 60K corresponding to the pump body 34K. 1) passes through a rounded intersection area between the side of the piston pressing member 60K and the inner edge IN as shown in FIG. 7C. Along with this, the rotation restricting projection 5 is pressed by the pressing pin 38a (serial number 1).
The piston pressing member 60 whose side on the 8K side is pressed
K is the pressing pin 38a by the urging force of the urging means 64K.
Contrary to when the side on the rotation restricting projection 58K side is pressed by (serial number 1), counterclockwise in the figure around the rotation center shaft 56K and around the outer end of the movement restricting hole 62K. As shown in FIG. 7D, the side on the rotation restricting projection 58K side is brought into contact with the rotation restricting projection 58K. During this rotation, the outer edge of the piston pressing member 60K does not press the piston 50K. Therefore, the piston 50K is maintained at the home position as long as the rotating body 37a is rotating in the Y direction.

As described above, the supply of only the yellow ink is performed by driving the motor 30 in the normal direction and turning on the clutch 40a to operate as an operating clutch. Is turned on to form an operation clutch, and the motor 30 is driven to rotate in the reverse direction. As for the operation, only the operation of the piston drive mechanisms 42K and 42Y is reversed.
Description is omitted.

As described above, in this embodiment, when the rotating plate 37a of the pump unit 32a is rotated in any one direction, only one of the pistons 50Y or 50K of the pump main bodies 34Y and 34K is driven. And the other piston 50Y or 50K of the pump body 34Y or 34K is not driven.

The operation of supplying ink only to the pump unit 32a has been described above.
The ink supply operation of the entire three pump units 32a, 32b, 32c will be briefly described. The pump units 32a, 32b, 32c have respective gears 36a, 36b,
For example, when supplying black ink and magenta ink, the controller CTL drives the motor 30 in the reverse direction, turns on the clutches 40a and 40c, and selects the clutch as an operation clutch. The output gear 30a is rotated counterclockwise in FIG. 3 by the reverse drive of the motor 30, and the gears 36a, 36b,
36c rotates clockwise, counterclockwise, and clockwise, respectively. Since the clutches 40a and 40c are on, the gears 36 are attached to the rotating bodies 37a and 37c.
a, 36c are transmitted, and the rotating bodies 37a, 37c
Rotates with the gears 36a and 36c. As a result, the pressing pins 38a on the rotating bodies 37a, 37c press the respective inner edges IN of the piston pressing members 60K, 60M in the direction in which the piston pressing members 60K, 60M approach the pistons 50K, 50M, and the piston 50K , 50M to supply black ink and magenta ink. But,
Since the pressing pins 38a on the rotating bodies 37a and 37c do not press the respective inner edges IN of the piston pressing members 60Y and 60LC, the piston pressing members 60Y and 60LC are not moved in the direction approaching the pistons 50Y and 50LC, and 50Y and 50LC do not supply yellow ink and light cyan ink.

At this time, the rotating body 37b remains stationary, and the piston pressing members 60C corresponding to the rotating body 37b,
60LM does not press pistons 50C, 50LM.

Therefore, the supply system for the four inks (cyan ink, light cyan ink, light magenta ink, and yellow ink) other than the black ink and the magenta ink is not supplied. Will not be heard.

As described above, the forward and reverse rotation directions of the output shaft of the motor 30 are selected, and the three clutches 40a and 40 of the three pump units 32a, 32b and 32c are selected.
By selecting one or more of the b and 40c to be able to transmit the rotational force, the six pump bodies 34K,
Any one or more of 4C, 34M, 34LC, 34LM, and 34Y can be selected and driven. Moreover, one of the selected pump bodies 34
K, 34C, 34M, 34LC, 34LM, or 34
Y ink ejection holes 46K, 46C, 46M, 46LC,
From 46LM or 46Y, the amount of ink ejected per predetermined time can be known.

The present invention is not limited to the above-described embodiment, and the ink supply unit 16 may have any number of pump units, any number of piston drive mechanisms, and any number of pump bodies. For example, even if the number of pump units is increased, two forward and reverse rotation directions of the output shaft of the motor 30 are selected, and one or more clutches of one or more pump units are selected so as to be able to transmit a rotational force. By doing so, the supply of ink in the desired pump body can be driven by one motor 30.

If the number of pump units to be used is one, only two forward and reverse rotation directions of the output shaft of one motor 30 are selected, and one or more pump units of one pump unit are provided. Any one of the main bodies can be driven as desired.

The pump unit 32a includes a pair of piston driving mechanisms 42K and 42Y,
a, 36b, and 36c are arranged so as to be symmetrical with respect to a straight line (a straight line extending vertically in FIG. 3) connecting the rotation centers of the pair of piston drive mechanisms 42K and 42Y to the gear 36a. They may be arranged so as to be point symmetric with the rotation center being the center of symmetry. In this case, as shown in FIG. 8, the pump bodies corresponding to both of the pair of piston drive mechanisms are supplied for supplying ink with high ink consumption (large ink supply), for example, black ink. Assuming that the pump bodies 34k and 34K 'to be used, when the rotating body 37a rotates in a predetermined direction, one pair of the piston driving mechanisms 42 at a time is used.
K and 42K 'are both a pair of pistons 50K and 50K'.
Is driven, a large amount of ink can be supplied in accordance with a high ink consumption.

Further, the desired pump body (here, 3
When the rotation plate corresponding to (4Y) is rotated by a desired number of rotations and the rotation is completed, as shown in FIG. 7C, the piston 50 of the desired pump body 34Y is stopped.
Inner edge IN of piston pressing member 60Y pressing Y
The rotating plate 37a finishes rotating with the pressing pin 38a (serial number 2) abutting on the pressing pin 38a, and the pressing pin 38a abutting on the rotation center of the rotating plate 37a and the inner end IN of the piston pressing member 60Y. (Serial number 2) and the piston pressing member 60
The outer edge of Y is the piston 5 of the desired pump body 34Y.
There is a case where the position where 0Y is pressed is substantially aligned with the straight line. That is, the direction of the force that the urging means 66Y of the piston 50Y urges the piston pressing member 60Y and the direction of the force that the pressing pin 38a of the rotating plate 37a presses the piston pressing member 60Y are substantially the above. They are aligned on a straight line. Then, the inner edge IN of the piston pressing member 60Y
Is formed so as to extend substantially perpendicular to the side of the piston pressing member 60Y on the side of the rotation restricting projection 58Y and the side opposite to the side of the rotation restricting projection 58Y. Until the rotation of 37a is resumed, the above-described state of being substantially aligned is maintained.

In such a case, the following problem occurs.

For example, when trying to drive the piston 50Y only once, the controller CTL operates the clutch 40
is turned on, and the clutch 40a is turned off when the pulse signal from the photo interrupter 54 is detected only five times. That is, the piston pressing member 60Y cannot be pressed by the pressing pin 38a (serial number 2) in FIG. 7C, and before the next pressing pin 38a (serial number 1) completely presses the piston pressing member 60Y. There is a possibility that the pulse signal is detected 5 times and the rotation is stopped,
The piston 50Y cannot be driven properly, and a desired amount of ink cannot be supplied.

To solve such a problem, as shown in FIG. 3, the inner edge IN of the piston pressing member 60Y is
Connects the rotation centers of the three gears 36a, 36b, and 36c when the side (lower side) of the piston pressing member 60Y on the rotation restricting protrusion 58Y side is in contact with the rotational restricting protrusion 58Y. It is configured to be inclined with respect to a straight line. Further, the intersection area between the inner edge IN and the corresponding side on the rotation regulating protrusion 58Y side is rounded.

If the inner edge IN of the piston pressing member 60Y and the intersection area are inclined and rounded as described above, the rotation of the rotating plate 37a is completed, and the rotation center of the rotating plate 37a and the piston pressing are stopped. A pressing pin 38a in contact with the inner edge IN of the member 60Y;
Even when the position where the outer edge of 0Y presses the piston 50Y is substantially aligned, the urging force of the urging means 66Y of the piston 50Y and the urging force of the urging means 64Y of the piston pressing member 60Y cause Piston pressing member 60Y
Press pin 3 of the rotating plate 37a which is in contact with the inner edge IN.
8a can be pushed back (the rotating plate 37a is freely rotatable because the clutch 40a is turned off).

Next, various ink supply control methods of the ink supply unit 16 in the ink jet printer according to the embodiment of the present invention having the above-described configuration will be described with reference to FIGS.

The sub ink tanks 21K, 21C,
21M, 21LC, 2LM, 21Y filters 7
4 (see FIGS. 5A and 5B) indicate that the amount of ink permeated by the filter 74 per unit time is (1). Corresponding inkjet heads 10K, 10C, 10M, 10
LC, 10LM, or 10Y is set to be equal to or larger than the ink consumption per unit time, or (2). Corresponding inkjet head 10K, 10C, 10M, 10L
C, set to be equal to or larger than the ink discharge amount per unit time during image recording of 10LM or 10Y, or (3). Corresponding inkjet head 10K, 10
C, 10M, 10LC, 10LM, or 10Y are set to be equal to or larger than the ink discharge amount per unit time during maintenance. With such a configuration, the inkjet heads 10K, 10C, 10M, 10LC, 10L
M, 10Y, while the sub ink tanks 21K, 21K
Even if the ink is supplied to C, 21M, 21LC, 2LM, and 21Y, no ink shortage occurs due to a delay in ink supply.

FIG. 9 is a flow chart of an ink supply control method for the sub ink tank 21K for black ink as an example of a first ink supply control method in the ink supply unit 16. Sub ink tanks 21C, 21M, 21LC, 21LM, for other color inks
The flow chart of the ink supply control method for 21Y is the same as that in FIG. Note that in the following description with reference to FIG.
(A) and (B), and FIGS. 3 and 7 for the description of the ink supply unit 16.

In the first ink supply control method, when the black ink level in the sub ink tank 21K decreases and the ink low level detector 86a is turned on (F1-
1) The output of the motor 30 of the ink supply unit 16 is to rotate the gear 36a of the pump unit 32a having the pump body 34K for black ink at a predetermined speed in the -Y direction in FIG. 7A. Drives the shaft, and the gear 36a
So that the rotating plate 37a rotates together with the pump unit 3.
The clutch 40a of 2a is also turned on (F1-2).

Thereafter, even if a predetermined time has elapsed (F1-3)
Ink low level detector 86a of sub ink tank 21K
Is not turned off (F1-4), it is determined that the ink supply unit 16 or the ink low level detector 86a has failed or the black ink in the ink bottle 12K is empty, and the motor 30 and the clutch 40a Is turned off (F1-5), and the controller CTL shown in FIG.
Is displayed on the display device connected to the device (F1-6). Specifically, "black ink supply system failure" or "black ink bottle needs replacement" is displayed.

If the ink low level detector 86a of the sub ink tank 21K is turned off (F1-4) before the predetermined time elapses (F1-4), the operation of the motor 30 and the clutch 40a is stopped. The process is continued until the 21K ink high level detector 86b is turned on (F1-
5). When the ink below the filter 74 of the sub ink tank 21K is sufficiently accumulated, the ink high level detector 86b is turned on, and the operation of the motor 30 and the clutch 40a is stopped by the controller CTL based on the ON signal. After that, it waits until the ink low level detector 86a of the sub ink tank 21K is turned on (F1-1).

Although the first ink supply control method is extremely simple in its control method and has the effect of reducing the load on the control system, it has the following disadvantages.

Normally, the black ink supplied to the sub ink tank 21K by the pump body 34K is
It takes some time to pass through. In other words, since the relationship of ink supply amount> filter transmission amount is satisfied, the supplied ink first accumulates in the upper ink storage section above the filter 74.

On the other hand, since the float 82 for detecting the amount of ink in the sub ink tank 21K is provided in the lower ink reservoir below the filter 74,
If the ink does not pass through the filter 74, the position of the float 82 cannot be raised, and further supply of the ink will be prompted. That is, although ink is supplied, there is a time lag for the ink high level detector 86b to detect it, and therefore the amount of ink accumulated in the upper ink reservoir further increases, overflows, and overflows from the excess ink discharge hole 76. It may be discharged. In order to avoid such waste of ink, a second ink supply control method described below has been proposed.

FIG. 10 is a flowchart of an ink supply control method for the sub ink tank 21K for black ink as an example of the second ink supply control method in the ink supply unit 16. Sub ink tanks 21C, 21M, 21LC, 21L for other color inks
FIG. 1 is a flowchart of an ink supply control method for M and 21Y.
It is similar to the case of 0. In the following description with reference to FIG. 10, the sub ink tank 21K will be described with reference to FIGS.
3 and 7 will be further referred to for the description.

In the second ink supply control method, the ink low level detector 8 of the sub ink tank 21K is used.
6a is turned on (F2-1), the ink supply unit 1
The motor 30 of FIG. 7 has a gear 36a of a pump unit 32a having a pump body 34K for black ink.
The output shaft is driven to rotate at a predetermined speed in the -Y direction in (A) (F2-2), and the clutch 40a of the pump unit 32a is also turned on so that the rotating plate 37a rotates together with the gear 36a (F2). -3).

At the same time, the controller CTL of FIG. 6 starts counting pulse signals from the photointerrupter 54 (F2-4). And the controller CT of FIG.
L indicates that when the count of the pulse signal reaches a predetermined number (71 in this embodiment) (F2-5), the clutch 4
The operation of 0a is turned off (F2-6).

As described above, the pulse plate 52 has 15 light-shielding arms, and the rotating plate 37a has three pressing pins 38a concentrically at equal intervals. Therefore, if the controller CTL of FIG. 6 counts the pulse signal from the photo interrupter 54 15 times, the rotating plate 37a makes one rotation, and the three pressing pins 38a on the rotating plate 37a correspond to the corresponding black ink. Piston 5 of pump body 34K
Reciprocate 0K three times. Therefore, when the pulse signal is counted five times, the piston 50K reciprocates once. As described above, the number of pulse signals necessary for reciprocating the piston 50K fourteen times is 14 × 5 = 70.
Further, as described above, in order to surely reciprocate the piston 50K 14 times, the number of necessary pulse signals is increased by one,
It is set to 1.

The amount of ink supplied by the reciprocating movement of the piston 50K fourteen times means that the black ink that cannot be transmitted immediately through the filter 74 of the sub ink tank 21K and gradually accumulates in the upper ink reservoir is discharged from the upper ink reservoir. This is the amount that is set as the degree of not overflowing.

The operation of the clutch 40a is turned off (F2
-6) After that, the timer built in the controller CTL of FIG. 6 starts counting (F2-7), and waits for the elapse of a predetermined time (14 seconds in this embodiment) (F2-8). ).

The 14 seconds set at the predetermined time is
This is the time required for the black ink accumulated in the upper ink storage portion, which cannot pass through the filter 74 of the sub ink tank 21K due to the 14 reciprocating operations of the piston 50K, to pass through the filter 74.

After the elapse of 14 seconds, the timer built in the controller CTL stops counting and is reset (F2-9), and then the ink high level detector 86b of the sub ink tank 21K is turned on. Is determined (F2-10). Here, if the ink high level detecting device 86b is not turned on, the steps from F2-3 to F2-10 are repeated.

When the controller CTL detects that the ink high level detector 86b has been turned on, the motor 3
0 operation is stopped. Next, the ink low level detector 86a of the sub ink tank 21K is turned on (F
Wait for 2-1).

In the second ink supply control method, the black ink supplied to the sub-ink tank 21K by the pump body 34K is effectively prevented from overflowing from the upper ink storage section of the sub-ink tank 21K, and Waste can be prevented.

In the second ink supply control method described above, the count of the pulse signal from the photo interrupter 54 can be used instead of the timer. In this case, there is an advantage in that the timer function is also used.

In the case where the ink permeation performance is extremely lowered due to the deterioration of the filter 74 or the case where the float 82 does not rise due to the failure, the ink overflows from the upper ink storage portion, but the excess ink discharge pipe 80
And an overflow sensor that detects when excess ink has reached the waste ink bottle, and based on the detection result of the overflow sensor, stops the ink supply and displays an error message on the display device. By configuring the CTL, waste of ink can be minimized.

FIG. 11 is a flowchart showing an ink supply control method for the sub ink tank 21K for black ink as an example of the third ink supply control method in the ink supply unit 16. Sub ink tanks 21C, 21M, 21LC, 21L for other color inks
FIG. 1 is a flowchart of an ink supply control method for M and 21Y.
The same as in the case of 1. In the following description with reference to FIG. 11, the description of the sub ink tank 21 </ b> K will be described with reference to FIGS.
3 and 7 will be further referred to for the description.

In the third ink supply control method, the ink low level detector 8 of the sub ink tank 21K is used.
6a is turned on (F3-1), the ink supply unit 1
The motor 30 of FIG. 7 has a gear 36a of a pump unit 32a having a pump body 34K for black ink.
(A) The output shaft is driven so as to rotate at a predetermined speed in the −Y direction (F3-2), and the clutch 40a of the pump unit 32a is also turned on so that the rotating plate 37a rotates together with the gear 36a (F3). -3).

At the same time, the controller CTL of FIG. 6 starts counting pulse signals from the photo interrupter 54 (F3-4). When the count of the pulse signal reaches a predetermined number (6 in this embodiment) (F3-5), the controller CTL turns off the operation of the clutch 40a (F3-6).

The count number 6 of the pulse signal corresponds to the amount of rotation of the gear 36a and, consequently, the rotating plate 37a sufficient to reciprocate the pump body 34Y for black ink once.

As described in the second ink supply control method, when the pulse signal is counted five times, the piston 50K reciprocates once. Further, as described above, the number of necessary pulse signals is increased by one and set to six in order to surely reciprocate the piston 50K once.

The controller CTL changes the pulse signal to 6
After counting the number of times (F3-5) and turning off the operation of the clutch 40a (F3-6), a timer built in the controller CTL starts counting (F3-7),
Wait for a predetermined time (1.9 seconds in this embodiment) to elapse (F3-8).

[0110] The predetermined time of 1.9 seconds is defined as the time when the black ink accumulated in the upper ink storage portion without being able to pass through the filter 74 of the sub ink tank 21K due to one reciprocating operation of the piston 50K. This is the time required to pass through 74 and the time required to suppress the variation in the supply amount due to one reciprocating operation of the piston 50K.

After the elapse of 1.9 seconds, the timer built in the controller CTL stops counting and is reset (F3-9), and then the ink high level detector 86b of the sub ink tank 21K Is turned on or not (F3-10). Here, if the ink high level detecting device 86b is not turned on, the steps from F3-3 to F3-10 are repeated.

When the controller CTL detects that the ink high level detector 86b has been turned on, the motor 3
0 operation is stopped (F3-11). Then, it waits until the ink low level detector 86a of the sub ink tank 21K is turned on (F3-1).

In the third ink supply control method, the black ink supplied to the sub ink tank 21K by the pump body 34K is used for the sub ink tank 21K, as in the second ink supply control method described above. In addition to effectively preventing overflow from the upper ink storage section and preventing waste of ink, it has the following effects.

When the piston 50K is continuously reciprocated, the piston 50K is pressed again from the piston pressing member 60K before returning to the home position by the urging means 66K, and the stroke amount of the piston 50K is initially planned. It becomes small for an appropriate stroke amount. For this reason, the desired amount of ink supply may not be reached, and the ink supply may be insufficient.

On the other hand, in the present ink supply control method, each time the piston 50K reciprocates once, the driving of the piston is stopped for 1.9 seconds, so that the piston 50K is biased during the 1.9 seconds. It is possible to sufficiently return to the home position by the means 66K, and is pressed again from the home position by the piston pressing member 60K. For this reason,
This has the effect of suppressing variations in the ink supply amount and always supplying an appropriate ink amount.

In the third ink supply control method, the photo interrupter 5 is used instead of the timer.
The count of the pulse signal from 4 can be used, but the accuracy is lower than that of the timer.

FIG. 12 is a flowchart of an ink supply control method for the sub ink tank 21K for black ink as an example of the fourth ink supply control method in the ink supply unit 16. Sub ink tanks 21C, 21M, 21LC, 21L for other color inks
FIG. 1 is a flowchart of an ink supply control method for M and 21Y.
The same as in the case of 1. Note that in the following description with reference to FIG. 11, the sub ink tank 21K will be described with reference to FIGS.
3 and 7 will be further referred to for the description.

In this ink supply control method, F4-
Steps 1 to F4-3, and F4-5 to F4-1
The second step is the step F in the third ink supply control method.
The contents are the same as the steps 3-1 to F3-11,
The step F4-4 in the present ink supply control method is a step not included in the third ink supply control method, and is particularly useful as an ink supply control method after ink bottle replacement.

Since the black ink bottle 12K has just been replaced, the ink low level detector 86a of the sub ink tank 21K is turned on (F4-1), and the motor 30 of the ink supply unit 16 supplies the black ink. The output shaft is driven to rotate the gear 36a of the pump unit 32a having the pump body 34K at a predetermined speed in the -Y direction in FIG. 7A (F4-2), and the gear 36a
So that the rotating plate 37a rotates together with the pump unit 3.
The clutch 40a of 2a is also turned on (F4-3).

Thereafter, the ink presence / absence detecting means 90 provided immediately before the ink supply hole 72 of the sub-ink tank 21K is provided.
Based on K, the presence or absence of black ink in the ink supply pipe 14K is detected (F4-4). Immediately after the replacement of the ink bottle 12K, the ink has not reached the ink supply pipe 14K immediately before the sub ink tank 21K, and the ink presence / absence detecting means 90K detects the absence of ink. When the ink absence is detected, the motor 30 is continuously driven until the ink presence / absence detection means 90K detects the presence of black ink, and the pump unit 32a is rotated so that the rotating plate 37a rotates continuously with the gear 36a. Clutch 4
0a is also kept on.

When the ink presence / absence detecting means 90K detects the presence of black ink in step F4-4, the controller CTL starts counting pulse signals from the photo interrupter 54 (F4-5). When the count of the pulse signal reaches a predetermined number (6 in this embodiment) (F4-6), the controller CTL turns off the operation of the clutch 40a (F4-7).

The controller CTL changes the pulse signal to 6
After counting the number of times (F4-6) and turning off the operation of the clutch 40a (F4-7), a timer built in the controller CTL starts counting (F4-8),
Wait for a predetermined time (1.9 seconds in this embodiment) to elapse (F4-9).

After 1.9 seconds have elapsed, the timer incorporated in the controller CTL stops counting and is reset (F4-10), and then the ink high level detector 86b of the sub ink tank 21K is turned on. Is determined (F4-11). Here, if the ink high level detection device 86b is not turned on, the control flow from F4-3 to F4-11 is repeated.

The controller CTL, which detects that the ink high level detector 86b has been turned on,
0 operation is stopped (F4-12). Then, it waits until the ink low level detector 86a of the sub ink tank 21K is turned on (F4-1).

In this fourth ink supply control method, the third
In addition to the effect of the ink supply control method described above, after the ink is replaced with a new ink bottle 12K, the output shaft is continuously driven to the motor 30 as described above until the ink presence / absence detecting means 90K continuously detects the presence of black ink. By keeping the clutch 40a of the pump unit 32a on so that the rotary plate 37a rotates continuously with the gear 36a, the new ink bottle 12
Black ink can be rapidly supplied from K to the sub ink tank 21K.

In the fourth ink supply control method, FIG.
Of the ink supply amount control means for changing the ink supply amount from the ink supply unit 16 to the sub-ink tank 21K according to the detection result of the presence or absence of the ink by the ink presence / absence detection means 90K. it is obvious.

The step F4-4 in the fourth ink supply control method described above is the same as the step F2-3 and the step F2-4 in the second ink supply control method shown in FIG. May be interposed between them. That is, when the ink presence / absence detecting means 90K detects the absence of black ink, it means that the corresponding ink bottle 12K is once empty. If the empty ink bottle 12K has been replaced with a new ink bottle 12K, the output shaft is continuously connected to the motor 30 until the ink presence / absence detecting means 90K detects the presence of black ink in step F4-4. By driving the clutch 40a of the pump unit 32a so that the rotary plate 37a rotates continuously with the gear 36a, the ink is supplied to the sub-tank 21K with black ink from the new ink bottle 12K. The ink supply pipe 14K up to the hole 72 can be quickly filled.

In the ink jet printer of the above-described embodiment, the outer cover open / close detector is connected to the controller CTL. The outer cover open / close detector detects that the outer cover of the ink jet printer has been opened. When the ink jet printer is turned on, all the operations of the ink jet printer are stopped.

As apparent from the above description with reference to FIGS. 1 to 11, the ink jet printer according to the present invention can be expressed as follows.

[0130] 1. An ink tank containing ink; an ink supply pipe connecting the ink tank and the ink jet head; and an ink supply unit provided in the ink supply pipe and supplying ink from the ink tank to the ink jet head. The ink supply unit includes a motor and a pump unit driven by the motor, and the pump unit is communicated with the ink tank by the ink supply pipe. A pump body having an ink suction hole and an ink ejection hole communicated with the ink jet head by the ink supply pipe, a piston body having a piston reciprocable in the cylinder, and two directions by the motor. Selectable rotation and center of rotation A rotating body provided with a pressing pin at a position separated from the rotating body, and a piston drive for driving the piston of the pump body in the cylinder by movement of the pressing pin accompanying rotation of the rotating body in one direction. And a mechanism.

[0131] 2. The pump unit has a pair of pump bodies and a pair of piston driving mechanisms, and one of the piston driving mechanisms is moved by the movement of the pressing pin accompanying rotation of the rotating body in one direction. The piston of the pump body is driven within the cylinder by the rotation of the rotating body in the other direction, and the other piston drive mechanism moves the piston of the other pump body into the cylinder by the movement of the pressing pin in the other direction. The inkjet printer according to the above item 1, wherein the inkjet printer is driven by:

3. An ink tank containing ink; an ink supply pipe connecting the ink tank and the ink jet head; and an ink supply unit provided in the ink supply pipe and supplying ink from the ink tank to the ink jet head. The ink supply unit includes: a motor; and a plurality of pump units selectively driven by the motor, wherein the plurality of pump units include the ink supply unit. A cylinder provided with an ink suction hole communicated with the ink tank by a tube and an ink ejection hole communicated with the ink jet head by the ink supply tube, and a piston that can reciprocate in the cylinder, Having a plurality of pump bodies and the one motor A plurality of rotating gears, a plurality of rotating bodies each of which is rotatable in two directions and a pressing pin is provided at a position separated from a center of rotation, and a plurality of rotating bodies each including the plurality of gears and the plurality of rotating bodies. A plurality of clutches interposed therebetween for selectively transmitting rotational driving force from the plurality of gears to the plurality of rotating bodies; and selectively transmitting rotational driving force from the corresponding plurality of gears by the plurality of clutches. A plurality of piston driving mechanisms for driving the pistons of the plurality of pump bodies in the cylinder by movement of the pressing pins in accordance with rotation of the plurality of rotating bodies in any one direction. An ink jet printer, characterized in that:

4. a pair of ink jet heads; a pair of ink tanks containing ink; a pair of ink supply pipes connecting the pair of ink tanks and the pair of ink jet heads; A single ink supply unit provided in the pair of ink supply pipes and configured to supply ink from the pair of ink tanks to the pair of inkjet heads. Including one motor and one pump unit driven by the one motor,
The one pump unit includes an ink suction hole communicated with one of the pair of ink tanks by one of the pair of ink supply tubes, and the pair of inkjet heads by the one of the pair of ink supply tubes. A first cylinder provided with an ink ejection hole communicated with one of the
A first piston reciprocable in the first cylinder;
A first pump main body having: an ink suction hole communicated with the other of the pair of ink tanks by the other of the pair of ink supply tubes; and the one of the pair of ink supply tubes by the other of the pair of ink supply tubes. A second cylinder provided with an ink ejection hole communicated with the other side of the inkjet head;
A second piston reciprocable in the second cylinder;
A second pump main body having: a rotating body selectively rotatable in two directions by the one motor and having a pressing pin provided at a position separated from a center of rotation; A first piston drive mechanism for driving the first piston of the first pump body in the first cylinder by movement of the pressing pin due to rotation, and accompanying rotation of the rotator in another direction. An ink jet printer, comprising: a second piston drive mechanism that drives the second piston of the second pump main body in the second cylinder by moving the pressing pin.

5. A plurality of ink jet heads; a plurality of ink tanks containing ink; a plurality of ink supply pipes connecting the plurality of ink tanks and the plurality of ink jet heads; and a plurality of ink supply pipes. One ink supply unit that supplies ink from the plurality of ink tanks to the plurality of inkjet heads, wherein the one ink supply unit is rotated by one motor and the one motor A plurality of gears; a plurality of pump units driven by the plurality of gears; and a plurality of pump units interposed between the plurality of gears and the plurality of pump units to selectively select the plurality of pump units from the plurality of gear units. And a plurality of clutches for transmitting rotational driving force to each of the plurality of pump units. An ink suction hole communicated with one of the plurality of ink tanks by one of the plurality of ink supply tubes, and a one of the plurality of ink jet heads by the one of the plurality of ink supply tubes. And an ink discharge hole connected to the
And a first cylinder reciprocable in the first cylinder.
A first pump body having: a first pump main body; an ink suction hole communicated with another one of the plurality of ink tanks by another one of the plurality of ink supply pipes; A second cylinder provided with an ink ejection hole communicated with another one of the plurality of inkjet heads by the another one of the ink supply pipes;
A second pump body having a second piston capable of reciprocating in the cylinder, and a rotational driving force from a corresponding one of the plurality of gears by a corresponding one of the plurality of clutches. A rotating body selectively transmitted and rotatable in two directions and provided with a pressing pin at a position away from the center of rotation, and a corresponding one of the plurality of gears by a corresponding one of the plurality of clutches The rotation driving force is transmitted from the one to the rotating body to the rotating body, the movement of the pressing pin accompanying rotation of the rotating body in one direction causes the first piston of the first pump main body to move to the first position. A first piston driving mechanism driven in the cylinder, and a corresponding one of the plurality of clutches transmits a rotational driving force from a corresponding one of the plurality of gears to the rotating body. The rotating body is in the other direction And a second piston drive mechanism for driving the second piston of the second pump body in the second cylinder by movement of the pressing pin accompanying rotation. And an inkjet printer.

6. An ink jet head; a sub ink tank for supplying ink to the ink jet head; a main ink tank provided separately from the sub ink tank and containing more ink than the sub ink tank; ink from the main ink tank to the sub ink tank And a filter provided in an ink flow path between the main ink tank and the sub ink tank to remove foreign matter in the ink, and the amount of ink permeated by the filter per unit time. Is set so as to be equal to or larger than the ink consumption per unit time of the ink-jet head.

7. 7. The ink jet head according to claim 6, wherein the amount of ink per unit time transmitted through the filter is set to be equal to or larger than the amount of ink discharged per unit time during image recording of the inkjet head. An inkjet printer according to item 1.

8. The method according to claim 6, wherein an amount of ink permeated by the filter per unit time is set to be equal to or larger than an amount of ink discharged per unit time during maintenance of the inkjet head. The ink-jet printer as described.

9. The inkjet printer according to any one of claims 6 to 8, wherein the inkjet head and the sub ink tank are mounted on a movable carriage.

10. An inkjet head; a sub-ink tank for supplying ink to the inkjet head;
A main ink tank provided separately from the sub ink tank and containing more ink than the sub ink tank; an ink supply unit for supplying ink from the main ink tank to the sub ink tank; a main ink tank and a sub ink tank Presence / absence detection means provided in the ink flow path between the main body and the main ink tank to the sub ink tank in accordance with the detection result from the ink presence / absence detection means An ink supply amount control means for changing an amount of ink supplied by the ink jet printer.

11. 11. The ink jet printer according to claim 10, wherein the ink supply amount control means causes the ink supply unit to supply the ink from the main ink tank to the sub ink tank based on the result of the absence of ink detected by the ink presence / absence detection means.

12. 12. The ink jet printer according to the above item 10 or 11, wherein the sub ink tank is provided with a filter for removing foreign matter in the ink.

13. 13. The inkjet printer according to any one of items 10 to 12, wherein the inkjet head and the sub-ink tank are mounted on a movable carriage.

[0143]

As is apparent from the above description, according to the ink jet printer according to the present invention, a large ink supply amount required for a large ink jet printer and a long time use can be maintained for a long time. Although it can withstand, and even if the type of ink used increases, it is possible to supply ink according to the amount of use of each type of ink, but the type of ink used increases There is no proportional increase in manufacturing cost and increase in external dimensions and weight.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a main part of an ink jet printer according to an embodiment of the present invention.

FIG. 2 is a view showing a piping of an ink supply pipe of the main part in the ink jet printer of FIG.

FIG. 3 is a schematic horizontal sectional view of an ink supply unit of the main part in the inkjet printer of FIG. 1;

FIG. 4 is a schematic cross-sectional view of an ink supply unit of the main part in the inkjet printer of FIG.

5A is a schematic longitudinal sectional view of a sub ink tank of the main part in the ink jet printer of FIG. 1; and FIG. 5B is a sectional view of one of the sub ink tanks of FIG. 5A. It is the schematic side view which notched the part.

FIG. 6 is a diagram schematically illustrating a configuration of an ink supply control system in the inkjet printer of FIG. 1;

FIGS. 7A, 7B, 7C, and 7D show an ink supply unit of an inkjet printer according to an embodiment of the present invention, in which an output shaft of one motor is rotated in one direction; 1 shows a state in which one of the pair of piston drive mechanisms of one pump unit does not drive one of the corresponding pair of pump bodies and the other piston drive mechanism drives the corresponding other pump body at the time of It is a horizontal sectional view.

FIG. 8 is a horizontal sectional view schematically showing a modified example of the pump unit of the ink supply unit of the inkjet printer according to the embodiment of the present invention.

FIG. 9 is a flowchart of a first ink supply control method of the ink supply unit in the ink jet printer according to the embodiment of the present invention.

FIG. 10 is a flowchart of a second ink supply control method of the ink supply unit in the inkjet printer according to one embodiment of the present invention.

FIG. 11 is a flowchart of a third ink supply control method of the ink supply unit in the ink jet printer according to one embodiment of the present invention.

FIG. 12 is a flowchart of a fourth ink supply control method of the ink supply unit in the inkjet printer according to one embodiment of the present invention.

[Explanation of symbols]

10K, 10C, 10M, 10LC, 10LM, 10Y
Inkjet head 12K, 12C, 12M, 112LC, 12LM, 12
Y ink bottle (ink main tank) 14K, 14C, 14M, 14LC, 14LM, 14Y
Ink supply pipe 16 Ink supply unit 18 Carriage 21K, 21C, 21M, 21LC, 21LM, 21Y
Sub ink tank 30 Motor 32a, 32b, 32c Pump unit 34K, 34C, 34M, 34LC, 34LM, 34
Y, pump body 36a, 36b, 36c gear 37a, 37b, 37c rotating plate 38a pressing member 40a, 40b, 40c clutch 42K, 42C, 42M, 42LC, 42LM, 42Y
Piston drive mechanism 44K, 44C, 44M, 44LC, 44LM, 44Y
Ink suction holes 46K, 46C, 46M, 46LC, 46LM, 46Y
Ink ejection holes 48K, 48C, 48M, 48LC, 48LM, 48Y
Cylinder 50K, 50C, 50M, 50LC, 50LM, 50Y
Piston 74 filter 90K, 90C, 90M, 90LC, 90LM, 90Y
Ink presence detection means CTL controller (ink supply amount control means)

Continued on front page F term (reference) 2C056 EA21 EA23 EA24 EB16 EB17 EB21 EB29 EB38 EB52 EB53 EC17 EC26 EC28 EC64 FA10 JC13 KA02 KB04 KB09 KB13 KB15 KB27 KB37 KC02 KC16 3H075 AA07 BB03 CC18 CC34 DA03 DB04

Claims (3)

[Claims] 1. An ink jet head; an ink tank containing ink; an ink supply pipe connecting the ink tank and the ink jet head; and an ink supply pipe provided in the ink supply pipe to supply ink from the ink tank to the ink jet head. An ink supply unit to perform;
In the ink jet printer, the ink supply unit includes a motor and a pump unit driven by the motor, wherein the pump unit communicates with the ink tank by the ink supply pipe. A pump body having a cylinder provided with a suction hole and an ink ejection hole communicated with the ink jet head by the ink supply pipe, and a piston capable of reciprocating in the cylinder; and selecting two directions by the motor. A rotating body that is rotatable and has a pressing pin at a position separated from the center of rotation, and the piston of the pump body is moved by the movement of the pressing pin accompanying rotation of the rotating body in one direction. And a piston drive mechanism driven in the cylinder. Jet printer. 2. The pump unit includes a pair of pump bodies and a pair of piston driving mechanisms, and one of the pump units is moved by the rotation of the rotating body in one direction. A piston drive mechanism drives the piston of one of the pump bodies in the cylinder, and the other piston drive mechanism moves the piston of the other pump body by the movement of the pressing pin accompanying rotation of the rotating body in another direction. The ink jet printer according to claim 1, wherein a piston is driven in the cylinder. 3. An ink jet head; an ink tank containing ink; an ink supply pipe connecting the ink tank and the ink jet head; and an ink supplied from the ink tank to the ink jet head provided in the ink supply pipe. An ink supply unit to perform;
In the inkjet printer comprising: the ink supply unit, one motor, a plurality of pump units selectively driven by the motor,
A cylinder provided with an ink suction hole communicated with the ink tank by the ink supply pipe and an ink discharge hole communicated with the ink jet head by the ink supply pipe. And a plurality of pump bodies each having a piston that can reciprocate in the cylinder; a plurality of gears rotated by the one motor; and positions each rotatable in two directions and separated from the center of rotation. A plurality of rotating bodies provided with pressing pins, and a rotational driving force is selectively transmitted from the plurality of gears to the plurality of rotating bodies between the plurality of gears and the plurality of rotating bodies. A plurality of clutches, and any one of the plurality of rotating bodies to which the rotational driving force is selectively transmitted from the plurality of gears corresponding to the plurality of clutches. Wherein said piston of said plurality of pump body by the movement of the pressing pin has a plurality of piston driving mechanism for driving in the cylinder, an ink jet printer, characterized in that with the rotation of the.