JPH10244681A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize the printer, to reduce the cost and to stably supply ink to a plurality of nozzle unit elements forming a nozzle unit. SOLUTION: An ink tank 213 is placed away from a nozzle unit 200. An ink supplying passage is constituted of a common supplying tube 215P of which one end is connected to the ink tank 213 and branch supplying tubes 215A-215D of which each one end is connected to the other end of the common supplying tube 215P via a supplying connection member 215Q and each of the other ends is connected to the corresponding respective nozzle unit elements 205A-205D. An ink resupplying passage is constituted of a common resupplying tube 217P of which one end is connected to the ink tank 213 and branch resupplying tubes 217A-217D of which each end is connected to the other end of the common resupplying tube 217P via a resupplying connection member 217Q and each of the other ends is connected to the corresponding respective nozzle unit elements 205A-205D.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer capable of printing while spraying ink from a plurality of nozzle unit elements of a nozzle unit onto a printing medium held on the outer peripheral surface of a rotating drum.

[0002]

2. Description of the Related Art A nozzle unit for each color is reciprocated over the entire length in a row direction, and printing is performed during each forward movement to print one line, and after one line printing, a printing medium (plain paper, OHP paper, etc.). Compared to a so-called serial type ink-jet printer which feeds M by one line in the column direction and repeats them, printing speed can be drastically increased and continuous printing operation can be performed over a large number of sheets. The present applicant has proposed an ink jet printer capable of achieving a large size reduction (for example, Japanese Patent Application No. 8-296957).

That is, in FIG. 5, a drum 10 is rotatable at a constant peripheral speed about an axis and can hold a print medium M on an outer peripheral surface 11 thereof. This drum 10
The nozzle unit 200 for each color (C, M, Y, B) is disposed in the rotation (Y) direction of the color filter.

Accordingly, an integrated nozzle unit 200 for each color in which a plurality of nozzle unit elements are arranged in the row direction.
Are ejected from the ink ejection ports of the inkjet nozzles 207 for each color while rotating the print medium M while reciprocating by the pitch between the inkjet nozzles 207, for example, and printing is performed in the row direction. The printing can be performed in the column direction while utilizing the rotation of the drum 10. That is, since the line-direction printing and the column-direction printing can proceed simultaneously, the printing speed can be greatly increased.

A medium feeding means 60 and a medium feeding means 90 are provided on one side (right side in FIG. 5) of the drum 10, and a medium separating means 140 and a medium discharging / conveying means are provided on the other side (left side in FIG. 5). 160 and direction switching means 190 are provided.

The medium feeding means 60 includes a cassette feeding means 7
The print medium M can be selectively fed one sheet at a time from either one of the manual feeding means 61 and the manual feeding means 61. Medium supply means 90
Supplies the fed print medium M to the drum 10 at a predetermined timing. The medium peeling means 140 peels the print medium M from the drum 10 after printing, and the medium discharge / transport means 160 discharges and transports the peeled print medium M leftward in FIG. The direction switching unit 190 selectively switches between the discharge tray 192 and the upper discharge tray 193.

In this manner, since the feeding, supply, holding, printing, peeling, and discharging and conveying of the print medium M can be continuously performed, multicolor printing of, for example, 20 sheets or more in A4 size can be performed in one minute.

More specifically, the nozzle unit 200 for each color
Is a plurality (for example, four) of nozzle unit elements (205) arranged in a direction perpendicular to the page of FIG. 6 (row direction).
A, 205B, 205C, 205D), and each nozzle unit element (205A to 205D) is provided with a large number (for example, 159) of inkjet nozzles 207. Each ink jet nozzle 207 is communicated with a common ink buffer 206. The ink jet method is, for example, but not limited to, ink jet by a spray control element 208 utilizing the shear deformation of a piezoelectric actuator.

Here, each color nozzle unit 20
0 nozzle unit elements (205A to 2A)
05D), as shown in FIG.
Is used to supply the ink for each color.

The ink supply means 210 includes a filter 214
And an ink tank 213 having
3, an ink supply path (ink supply tube 215) for connecting the ink cassette 211 detachable via the liquid level stabilizing means 212, the ink tank 213 and each nozzle unit element (205A to 205D), and an urging means. 216
And an ink supply path (ink supply tube 217). In FIG. 6, reference numeral 218 denotes a tube opening / closing means.

The ink tank 213 is provided at a position separated from the nozzle unit 200 for each color. For this reason,
Compared with a conventional ink jet printer in which the ink tank 213 is integrated with the nozzle unit 200, the nozzle unit 200 can be made lighter, and the reciprocating speed in the row direction can be greatly increased. Since the capacity of the tank 213 can be greatly increased, a continuous printing operation of, for example, 500 or more sheets can be performed.

The urging means 216 has a plurality of (four) pressing rollers 216R and is of a rotary type which is rotated by a motor (not shown), and engages with each ink supply tube 215 (rotating pressing engagement). Thus, the respective color inks can be urged (pressurized and supplied) toward the respective color nozzle unit elements (205A to 205D). In addition, tube opening / closing means 218
Is a rotary type having one pressing roller 218R.

In this case, when each of the urging means 216 is driven in a state where the ink supply tube 217 is opened by each tube opening / closing means 218 at the time of initial filling of the ink into the ink buffer 206 or at the time of turning on the printer power, etc. The buffer 206 and the ink jet nozzle 207 can be initially filled with ink, and the ink in the ink buffer 206 can be refreshed.

Further, in a state where the ink supply tube 217 is closed by each tube opening / closing means 218, each urging means 216 is provided.
Is driven, the nozzle unit element for each color (205
A to 205D), it is possible to pressurize and supply (energize) the color ink from the ink tank 213 into the ink buffer 206, and to perform priming as it is to eliminate air bleeding near each inkjet nozzle and clogging of each nozzle. Can be prevented.

If printing is performed with the urging means 216 stopped and the ink supply tube 217 opened by the tube opening / closing means 218, the ink reduced by ink-jet can be supplied from the ink tank 213 to the ink supply tube 217 by a capillary effect or the like. Through the ink buffer 2
06 automatically.

[0016]

By the way, in the previously proposed ink jet printer, as shown in FIG. 7, one nozzle unit 200 [four nozzle unit elements (205)
A to 205D)] and the ink tank 213 (ink supply tube 215, ink supply tube 2).
17), eight urging means 216 and four tube opening / closing means 218 are provided, so that, for example, yellow (Y), magenta (M), cyan (C), and black (B) are printed. (Ie, when there are four nozzle units 200), 8 × 4 = 32 tubes, 4 × 4 = 16 urging means 216, 4 × 4 = 16
The number of tube opening / closing means 218 will be provided.

For this reason, the number of components increases and a large installation space is required, making it difficult to reduce the size and cost. Further, since the nozzle units 200 for each color and the ink tanks 213 for each color are spaced apart from each other, a very large space is required to route all the tubes (215, 217) from the nozzle units 200 for each color to the ink tanks 213 for each color. This makes it difficult to reduce the size.

An object of the present invention is to provide an ink jet printer which can reduce the size and cost and can stably supply ink to each nozzle unit element of the nozzle unit.

[0019]

According to the first aspect of the present invention, ink is supplied from a plurality of nozzle unit elements of a nozzle unit to a printing medium held on an outer peripheral surface of a drum rotatable at a constant peripheral speed and rotating with the drum. An ink jet printer capable of performing printing while spraying, wherein an ink tank is provided at a position distant from the nozzle unit, and ink supply means capable of supplying ink in the ink tank to the nozzle unit is provided. An ink supply path connecting the ink tank and the nozzle unit, an ink supply path, and a biasing means provided in the ink supply path, the ink supply path having a common supply having one end connected to the ink tank. One end of the tube is connected to the other end of the common supply tube via a supply connection member, and The ink supply path is formed from each of the corresponding nozzle unit elements and each of the branch supply tubes connected thereto, and the ink supply path is connected to one end of the common supply tube connected to the ink tank, and one end is connected to the other end of the common supply tube. It is characterized in that it is formed by a branch supply tube connected via a supply connection member and having the other end connected to the corresponding nozzle unit element.

In this case, the same number of supply and connection tubes as the nozzle unit elements are required between each nozzle unit element and the supply connection member (supply connection member). Since ink is supplied by one tube (common supply tube, common auxiliary tube) between the connection member (supply connection member) and the ink tank, the number of tubes is substantially reduced and the installation space is significantly reduced. Can be achieved. Further, it is not necessary to route all the tubes connected to the respective nozzle unit elements to the ink tank disposed apart from the nozzle unit. Ink supply includes ink supply.

Therefore, downsizing and cost reduction can be achieved, and ink can be stably supplied to each nozzle unit element.

According to a second aspect of the present invention, there is provided an ink jet printer in which the urging means is provided in the common supply tube.

In the case of this invention, it is sufficient to provide only one urging means, and it is not necessary to provide the urging means by the number of nozzle unit elements. Therefore, ink can be stably supplied to each nozzle unit element and the apparatus can be further improved. Can be reduced in size and cost.

According to a third aspect of the present invention, it is possible to print while spraying ink from a plurality of nozzle unit elements of a nozzle unit onto a print medium which is held on the outer peripheral surface of a drum rotatable at a constant peripheral speed and is rotating with the drum. An ink jet printer, wherein an ink tank is provided at a position distant from a nozzle unit, ink supply means capable of supplying ink in the ink tank to the nozzle unit is provided, and the ink supply means comprises an ink tank and a nozzle unit. An ink supply path and an ink supply path connecting
A supply tube having one end connected to the ink tank and the other end connected to one of the nozzle unit elements, the supply tube being formed from biasing means provided in the ink supply path; A connection supply tube connecting each nozzle unit element to each other, and forming an ink supply path with a supply tube having one end connected to the ink tank and the other end connected to one of the nozzle unit elements. , And a connection supply tube connecting the nozzle unit elements to each other.

In the case of this invention, each of the ink supply path and the ink supply path is substantially formed by one tube. Further, only one urging means is required. Therefore, the size and cost of the apparatus can be further reduced. Further, since the ink supply path and the ink supply path are each substantially formed by one tube, ink can be supplied to each nozzle unit element under the same conditions. In addition, by using substantially one tube, it is possible to eliminate variations in the amount of ink supplied to each nozzle unit element due to a difference in the length of each tube from the supply connection member (supply connection member). Thus, ink can be supplied to each nozzle unit element under the same conditions. As a result, higher quality printing can be performed.

According to a fourth aspect of the present invention, it is possible to print while spraying ink from a plurality of nozzle unit elements of a nozzle unit onto a print medium which is held on the outer peripheral surface of a drum rotatable at a constant peripheral speed and is rotating with the drum. An ink jet printer, wherein an ink tank is provided at a position distant from a nozzle unit, ink supply means capable of supplying ink in the ink tank to the nozzle unit is provided, and the ink supply means comprises an ink tank and a nozzle unit. An ink supply path and an ink supply path connecting
A biasing means provided in the ink supply path, the ink supply path having a common supply tube having one end connected to the ink tank, and a supply connection member having one end connected to the other end of the common supply tube. Are formed through a plurality of supply tubes connected to each other via a nozzle unit element having a different end, and a connecting supply tube connecting the nozzle unit elements to each other. A common supply tube connected to the ink tank, and a plurality of supply units each having one end connected to the other end of the common supply tube via a supply connection member and each other end connected to a different nozzle unit element. It is formed of a tube and a connecting supply tube connecting the nozzle unit elements, and the urging means is provided in the common supply tube.

In the case of this invention, since the ink is supplied from the ink tank to each nozzle unit element via the supply connection member (supply connection member), the number of tubes and the installation space are significantly reduced. I can do it. Further, it is not necessary to route all the tubes connected to the respective nozzle unit elements to the ink tank disposed apart from the nozzle unit. Therefore, downsizing and cost reduction can be achieved, and ink can be stably supplied to each nozzle unit element.

Further, since the respective nozzle unit elements are connected to each other and ink is supplied from the ink tank to a plurality of the nozzle unit elements, for example, a large amount of ink is continuously supplied from all the nozzle unit elements. Even if the ink is ejected, it is possible to prevent a situation in which the ink supply to each nozzle unit element is insufficient. Therefore, ink can be more stably supplied to each nozzle unit element.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG.
As shown in FIG. 2 and FIG. 2, the basic configuration is the same as that of the previously proposed ink jet printer (FIGS. 5 to 7).
Ink supply path [shared supply tube 215P, supply connection member (215Q), branch tube (215A to 215A)
5D)] and the ink supply path [shared supply tube 21
7P, connecting member for supply (217Q), each branch tube 2
17A to 217D], the urging means 216 and the like, so that the installation space of the tube can be significantly reduced.

The same components as those of the previously proposed ink jet printer (FIGS. 5 to 7) are denoted by the same reference numerals, and the description thereof will be simplified or omitted.

The nozzle unit 200 for each color is provided separately from the ink supply means 210 (ink tank 213 etc.), and a plurality (for example, four) of nozzle unit elements (205A, 205B, 205C, 205D) are provided. And are displaced in the rotational movement (Y) direction of the drum 10. In other words, as shown in FIG. 2, the nozzle unit 200 for each color is divided into N (= 4) nozzle units (205A) in the direction of the drum axis (X).
To 205D). Each nozzle unit element (205A, 205B, 205C, 205D)
Are the lengths of S1, S2, S3, and S4 shown in FIG.
It is.

More specifically, the nozzle unit element (205)
A, 205C) and the nozzle unit elements (205B, 20)
5D) are spaced apart in the drum axis direction, that is, in the X direction, and displaced in the Y direction via the connection support bar 204, and are generally indirectly continuous in the X direction at different levels in the Y direction. It is arranged in.

Each nozzle unit element (205A) includes:
A large number (159) of inkjet nozzles 207a to 207n are arranged at a constant pitch PT (1/75 inch) within a length Lxa (2.11 inches). Height (Figure 2
Ly in the vertical direction) is 9 mm. X (X1, X2)
Nozzles 2 at each end of each nozzle unit element 205 adjacent in the direction and displaced in the Y direction
A constant pitch PT (1/75 inch) is maintained between 07n and 207a.

The nozzle unit 200 for each color is Y
It is arranged so as to be displaced in the direction by a predetermined pitch Yp (for example, 20 mm). In this embodiment, the order of arrangement from the upstream side to the downstream side in the Y direction is cyan C, magenta M, yellow Y, and black B.

As shown in FIG. 1, the ink supply means 210 includes an ink tank 213 and an ink supply path (21) connecting the ink tank 213 and the nozzle unit 200.
5P, 215Q, 215A to 215D) and ink supply paths (217P, 217Q, 217A to 217D)
And ink supply paths (215P, 215Q, 215A-
215D), and pressurizes the ink in the ink tank 213 with the nozzle unit 200.
Of the nozzle unit elements (205A to 205D).

One end of the ink supply path is connected to a common supply tube 215P connected to the ink tank 213, and one end is connected to the other end of the common supply tube 215P via a supply connection member (ink terminal 215Q). And each nozzle unit element (2
05A, 205B, 205C, 205D) connected to the respective branch supply tubes (215A, 215B, 215C,
215D).

The ink supply path is connected to the common supply tube 217P having one end connected to the ink tank 213, and connected to the other end of the common supply tube 217P via a supply connection member (ink terminal 217Q). And each nozzle unit element (2
05A, 205B, 205C, 205D) and each branch supply tube (217A, 217B, 217C,
217D).

The urging means 216 includes the common supply tube 21.
5P. In addition, the common supply tube 217
A tube opening / closing means 218 is provided at P.

In the case of the ink jet printer having such a configuration, between the nozzle unit elements (205A to 205D) and the supply connection member (215Q), and between each nozzle unit element (205A to 205D) and the supply connection member (21).
7Q), the nozzle unit elements (20
5A to 205D) and supply and supply tubes [each branch supply tube (215A to 215D), each branch supply tube (217A to 217D)], but each connection member (215Q, 217Q). Since ink is supplied by one tube (common supply tube 215P and common supply tube 217P) to the ink tank 213, the number of tubes and the installation space can be substantially reduced.

Further, it is not necessary to route the entire number of tubes connected to each of the nozzle unit elements (205A to 205D) to the ink tank 213 disposed apart from the nozzle unit 200.

Therefore, it is possible to reduce the size and cost, and it is possible to reduce the size of each nozzle unit element (205A to 205A).
Ink can be supplied stably to D).

Further, since the urging means 216 is provided in the common supply tube 215P, it is sufficient to provide only one, and it is not necessary to provide the urging means 216 by the number of nozzle unit elements (205A to 205D). Therefore, the size and cost of the apparatus can be further reduced. In addition, since the tube opening / closing means 218 is provided in the common supply tube 217P, it is sufficient to provide only one opening / closing tube 218. From this point, the size and cost of the apparatus can be further reduced.

(Second Embodiment) A second embodiment is shown in FIG. In such an ink-jet printer, the ink supply path is formed by the supply tube 215 and each connection tube 215R, and the ink supply path is formed by the supply tube 217 and each connection tube (2R).
15R).

The supply tube 215 has one end connected to the ink tank 213 and the other end connected to one of the nozzle unit elements 205 (for example, the nozzle unit element 205A). Each connecting tube 215
R represents each nozzle unit element (215A, 215B, 2
15C, 215D).

The supply tube 217 has one end connected to the ink tank 213 and the other end connected to one of the nozzle unit elements 205 (for example, the nozzle unit element 205B). Each connection tube forming the ink supply path connects the nozzle unit elements (215A, 215B, 215C, 215D) with each other. In this embodiment, each connection tube 215R forming the ink supply path is used. It is formed. The urging means 216 is provided in the supply tube 215. The supply tube 217 is provided with a tube opening / closing means 218.

In the case of the ink jet printer having such a configuration, each of the ink supply path and the ink supply path is substantially formed by one tube. Also,
Only one urging means 216 and one tube opening / closing means 218 are required. Therefore, the size and cost of the apparatus can be further reduced.

Further, by making the number of tubes substantially one, it is possible to eliminate variations in ink supply amounts to the nozzle unit elements (205A to 205D) due to differences in the length of each tube from the ink terminal. Thus, ink can be supplied to each nozzle unit element (205A to 205D) under the same conditions, and higher quality printing can be achieved.

(Third Embodiment) A third embodiment is shown in FIG.
Is shown in In such an inkjet printer, an ink supply path has a common supply tube 215P having one end connected to the ink tank 213, and one end has the other end of the common supply tube 215P and a supply connection member (ink terminal 215Q). Each supply tube (215A, 215B) connected to each unit element (for example, 205A, 205B) which is connected and each other end of which is different,
A common supply tube 217P having one end connected to the ink tank 213, and a common supply tube 21 having one end connected to the ink tank 213, the connection supply tube being formed from a connection supply tube connecting the nozzle unit elements (205A to 205D).
7P and the supply connection member (ink terminal 21).
7Q) and the respective supply unit tubes (217C, 217D) connected to different unit elements (for example, 205C, 205D) at the other end, and the respective nozzle unit elements (205A to 205D). And a connected supply tube.

In this case, the connection supply tube is a nozzle unit element (205A and 205C, 205B and 20B).
5D) and the tubes (217C, 217D) connecting the nozzle unit elements (205C and 205D) via the ink terminals 217Q.
And is formed from

The connection supply tube is formed using the connection supply tube. Common supply tube 215
P is provided with biasing means 216. The common supply tube 217P is provided with a tube opening / closing means 218.

In the case of an ink jet printer having such a configuration, the ink terminal 215Q (ink terminal 21)
7Q), the ink is supplied from the ink tank 213 to the nozzle unit elements (205A to 205D), so that the number of tubes can be substantially reduced and the installation space can be significantly reduced.

Further, it is not necessary to route all the tubes connected to each of the nozzle unit elements (205A to 205D) to the ink tank 213 disposed apart from the nozzle unit 200. Therefore, miniaturization and cost reduction can be achieved, and each nozzle unit element (2
05A to 205D).

Each nozzle unit element (205A to 205A)
205D) are connected to each other and ink is supplied from the ink tank 213 to a plurality of nozzle unit elements (205A to 205D). Thus, even if a large amount of ink is ejected, it is possible to prevent a situation where ink supply to each nozzle unit element (205A to 205D) becomes insufficient. Therefore, ink can be more stably supplied to each nozzle unit element (205A to 205D).

[0054]

According to the first aspect of the present invention, the ink supply is provided at a position apart from the nozzle unit and the ink supply means capable of supplying the ink in the ink tank to the nozzle unit is provided. The means is formed by an ink supply path, an ink supply path, and an urging means, and the ink supply path is formed by a common supply tube having one end connected to the ink tank, and one end being connected to the other end of the common supply tube. Each branch supply tube is connected to the corresponding nozzle unit element and connected to the corresponding nozzle unit element via the supply connection member. The ink supply path is shared with one end connected to the ink tank. One end of the supply tube is connected to the other end of the common supply tube via a supply connection member, and the other end is connected to the corresponding nozzle unit element. Since formed from the branch supply tube, ink can be a to stably supply high-quality printing in a plurality of nozzle units elements forming a can be and the nozzle unit to reduce the size and cost reduction.

According to the second aspect of the present invention, since the urging means is provided in the common supply tube, the same effect as that of the first aspect of the invention can be obtained, and the size and cost of the apparatus can be further reduced. Reduction can be achieved.

According to the third aspect of the present invention, the ink tank is disposed at a position separated from the nozzle unit, and the ink supply means capable of supplying the ink in the ink tank to the nozzle unit is provided. The means is formed by an ink supply path and an ink supply path connecting the ink tank and the nozzle unit, and an urging means provided in the ink supply path. The ink supply path has one end connected to the ink tank and The other end is formed from a supply tube connected to one of the nozzle unit elements and a connection supply tube connecting the nozzle unit elements to form an ink supply path, one end of which is connected to the ink tank and A supply tube having the other end connected to one of the nozzle unit elements, and a connection connecting the nozzle unit elements to each other Since formed from a sheet tube,
Further downsizing and cost reduction can be achieved. In addition, ink can be supplied to each nozzle unit element under the same conditions more reliably. Therefore, higher quality printing can be achieved.

According to the fourth aspect of the present invention, the ink tank is provided at a position distant from the nozzle unit, and the ink supply means capable of supplying the ink in the ink tank to the nozzle unit is provided. The means is formed by an ink supply path and an ink supply path connecting the ink tank and the nozzle unit, and an urging means provided in the ink supply path. The ink supply path has one end connected to the ink tank. A common supply tube, a plurality of supply tubes having one end connected to the other end of the common supply tube via a supply connection member and the other end connected to a corresponding nozzle unit element; Formed from a connection supply tube connecting the
A common supply tube having one end connected to the ink tank and a nozzle unit element having one end connected to the other end of the common supply tube via a supply connection member and the other end corresponding to the ink supply path. And a connecting supply tube connecting the nozzle unit elements to each other, so that the size and cost can be further reduced. Further, even if a large amount of ink is continuously ejected from all the nozzle unit elements, the ink can be supplied more reliably by each nozzle unit element, and as a result, higher quality printing can be achieved.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a first embodiment of the present invention.

FIG. 2 is also a diagram for explaining the arrangement of each nozzle unit element.

FIG. 3 is a perspective view for explaining a second embodiment of the present invention.

FIG. 4 is a perspective view for explaining a third embodiment of the present invention.

FIG. 5 is a diagram for explaining a previously proposed inkjet printer.

FIG. 6 is a diagram for explaining an ink supply unit.

FIG. 7 is a view for explaining a connection state between each nozzle unit element and an ink supply unit.

[Explanation of symbols]

 Reference Signs List 10 drum 11 outer peripheral surface 200 nozzle unit 205A to 205D nozzle unit element 210 ink supply means 213 ink tank 215 supply tube 215P shared supply tube 215Q ink terminal (supply connection member) 215A to 215D branch supply tube 216 urging means 217 supply Tube 217P Common supply tube 217Q Ink terminal (supply connection member) 218 Tube opening / closing means

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroyuki Takada 570 Ohito, Oni-cho, Tagata-gun, Shizuoka Prefecture Inside the Tech Ohi Works, Inc.

Claims (4)

[Claims] 1. An ink jet printer which is held on an outer peripheral surface of a drum rotatable at a constant peripheral speed and is capable of printing while spraying ink from a plurality of nozzle unit elements of a nozzle unit onto a print medium rotating with the drum. An ink tank disposed at a position distant from the nozzle unit, ink supply means capable of supplying ink in the ink tank to the nozzle unit, and an ink supply means connecting the ink tank and the nozzle unit. The ink supply path is formed by a supply path and an ink supply path, and a biasing means provided in the ink supply path. The ink supply path is formed by a common supply tube having one end connected to the ink tank and one end being formed by the common supply tube. Each nozzle unit element is connected to the other end via a supply connection member, and each other end corresponds to a corresponding nozzle unit element. The ink supply path is formed from each of the connected branch supply tubes, and the ink supply path is formed via a common supply tube having one end connected to the ink tank and one end connected to the other end of the common supply tube via a supply connection member. An ink jet printer which is formed from a branch supply tube which is connected and whose other end is connected to each corresponding nozzle unit element. 2. The ink jet printer according to claim 1, wherein said urging means is provided in said common supply tube. 3. An ink jet printer which is held on an outer peripheral surface of a drum rotatable at a constant peripheral speed and is capable of printing while spraying ink from a plurality of nozzle unit elements of a nozzle unit onto a print medium rotating with the drum. An ink tank disposed at a position distant from the nozzle unit, ink supply means capable of supplying ink in the ink tank to the nozzle unit, and an ink supply means connecting the ink tank and the nozzle unit. The ink supply path is formed from a supply path and an ink supply path, and an urging means provided in the ink supply path. The ink supply path has one end connected to the ink tank and the other end connected to one of the nozzle unit elements. Formed from a connected supply tube and a connected supply tube connecting each nozzle unit element to each other, The ink supply path is formed of a supply tube having one end connected to the ink tank and the other end connected to one of the nozzle unit elements, and a connection supply tube connecting the nozzle unit elements. An ink jet printer, characterized in that: 4. An ink jet printer which is held on an outer peripheral surface of a drum rotatable at a constant peripheral speed and is capable of printing while spraying ink from a plurality of nozzle unit elements of a nozzle unit onto a print medium rotating with the drum. An ink tank disposed at a position distant from the nozzle unit, ink supply means capable of supplying ink in the ink tank to the nozzle unit, and an ink supply means connecting the ink tank and the nozzle unit. The ink supply path is formed by a supply path and an ink supply path, and an urging means provided in the ink supply path. The ink supply path is formed by a common supply tube having one end connected to the ink tank and one end being formed by the common supply tube. Connected to the other end via the supply connection member and each other end to a different nozzle unit element And a connecting supply tube connecting the nozzle unit elements to form an ink supply path, one end of which is connected to the ink tank, and one end of which is a common supply tube. A plurality of supply tubes connected to the other end of the nozzle unit via a supply connection member and each other end is connected to a different nozzle unit element, and a connection supply tube connecting the nozzle unit elements to each other. And an urging means provided in the common supply tube.