JP2000211118A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet printer preventing the transmission of vibration in a main scanning direction or a sub-scanning direction to a unit main body including a nozzle head located at lower printing position from a lift means. SOLUTION: A unit main body 10UB is formed so as to be liftable between a lower printing position and an upper non-printing position along a lift guide means capable of prescribing a position in main scanning and sub-scanning directions by a lift means 40 and the roller guide surface and the guide roller for prescribing the position in the main scanning direction on the side of the unit main body 10UB forming the lift guide means are formed so as to be incapable of coming into contact with each other at the lower printing position but to be capable of permitting the displacement in the main scanning direction of the unit main body held at the lower printing position by a head printing position holding means 30 and further formed so as to be capable of bringing the unit main body held at the lower printing position by the head printing position holding means into contact with a stationary elastic positioning member 70 by utilizing the biassing force in the main scanning direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle head having a large number of ink jet nozzles arranged in the main scanning direction with respect to a printing surface, and a lower printing position and an upper non-printing position in an axial direction perpendicular to the printing surface. Is formed so as to be able to move up and down along the elevating guide means capable of regulating the position in the main scanning direction and the sub-scanning direction by the elevating means, and the nozzle held by the stationary head print position holding means at the lower printing position The present invention relates to an ink jet printer that performs printing by discharging ink from a head to a printing surface.

[0002]

2. Description of the Related Art A nozzle head for each color, in which an ink cassette is mounted, is reciprocated over the entire length in the main scanning direction, and printing is performed while spraying ink from the nozzle head onto a printing surface during each forward movement. (Or 1 / N line)
Print medium (plain paper, O
Compared to a so-called serial type ink jet printer which feeds one line in the sub-scanning direction and repeats these operations, the printing speed can be greatly increased and continuous printing operation can be performed on a large number of sheets. Compared with the so-called laser printer of the photographic system, the applicant proposed an inkjet printer that can achieve a significant reduction in size (for example,
JP-A-10-138520).

In FIG. 5, which shows a schematic configuration of the proposed printer, a paper feeding unit 81 including a paper cassette 81C, a manual feed tray 81T and the like are provided below the main body 1, and an ink supply unit 82 is provided on the left side. An ink supply means 88 including a tank 89 and a supply pump is provided. The drum 5 constituting the rotating body is rotated at a high speed (for example, 120 RPM) about the axis Z in the sub-scanning direction, that is, the R direction. The outer peripheral surface of the drum 5 forms a print surface, and the print medium is wound and held around the outer peripheral surface (print surface) of the drum by medium holding means (not shown), and rotates synchronously with the print surface.

[0004] A nozzle unit 10U is incorporated in the unit body 10UB.
The nozzle heads 10C, 10M, 10Y, and 10K for the respective colors (cyan C, magenta M, yellow Y, and black B) separated in the R direction (sub-scanning direction) shown in FIG. Each nozzle head 10C, 10M, 10Y, 10K
Is perpendicular to the printing surface (the outer peripheral surface of the drum 5). Further, the tips of the nozzles are aligned on a circular locus corresponding to the outer peripheral surface. This is for establishing each gap to a predetermined value (for example, 1 mm).

[0005] The nozzle unit 10U (10C, 10M,
10Y, 10K) is reciprocated by a reciprocating means (not shown) in the main scanning direction by a predetermined distance (for example, the pitch between the inkjet nozzles), and is line-printed on the rotating drum 5, that is, the printing medium. Column printing in the sub-scanning direction while utilizing the rotation of.
That is, the row printing and the column printing can proceed simultaneously by using the high-speed rotation of the drum 5, so that the printing speed can be significantly increased (for example, 20 PPM). When printing of one page is completed, the nozzle unit 10U is moved backward to return to the original position, and thereafter, the forward movement of the next page is started.

The printed printing medium is peeled off from the drum 5 and discharged by discharge means (not shown). Ink is supplied to the nozzle unit 10U from an ink supply unit 88 including an ink tank 89, a supply pump, and the like. In addition, the nozzle heads 10C, 10M for each color,
Since 10Y and 10K can be arranged at positions separated from the ink tanks 89 for the respective colors, the nozzle heads for the respective colors can be made lighter, and the reciprocating speed in the row direction can be greatly increased. Since the capacity of the ink tank for each color can be greatly increased, a continuous printing operation of, for example, 500 or more sheets can be performed.

In order to perform continuous printing operation on such a large number of printing media, each color nozzle head 10C, 10M, having a large number (for example, 2000) of inkjet nozzles arranged in the main scanning direction with respect to the printing surface. 10Y,
It is desirable to perform 10K maintenance (prevention of clogging, etc.) at predetermined time intervals.

Thus, the elevating means 4 is provided on the upper right side of the main body 1.
0 is arranged. The elevating means 40 includes a motor 41 of the main body (stationary side) 1, a worm gear mechanism 45, a pinion 42, an elevating body 46 including a rack member, and the like, and is connected via a head support member 60 to the unit main body 10UB.
(Nozzle heads 10C, 10M, 10Y, and 10K) are moved up and down along the vertical axis Y between the lower printing position PP shown in FIG. 6 and the upper non-printing position NPP shown in FIGS. Make it possible.

In the upper non-printing position NPP, each nozzle head 10 is formed so as to be capable of maintenance using the maintenance means 90 shown in FIGS.
The maintenance means 90 includes a washing board 91, and each of the nozzle heads 10C, 10M, 10Y, and 10B positioned at the maintenance position MP shown in FIG.
During maintenance (prevention of clogging), the ejected ink is received and discharged to, for example, a waste ink bottle.

In the washing board 91, the nozzle unit 10U has an upper non-printing position NP shown in FIG.
In the case of P, the rotating means 95 rotates from the standby position shown in FIG. 7A and is positioned as shown in FIG. After that, the lifting / lowering means 40 moves the nozzle unit 10U (nozzle heads 10C, 10M, 10Y, 10Y).
B) is lowered to the maintenance position MP shown in FIG.

After maintenance is completed, the nozzle heads 10C, 10M, 10Y, and 10K for the respective colors are returned to the original positions in FIG. 6A, and the gap between the nozzle tip and the printing surface (the outer peripheral surface of the drum 5) (for example, 1 mm) can be established and maintained.

Here, in order to stably raise and lower the unit main body 10UB using the lifting / lowering means 40, the unit main body 10UB must be accurately connected to the lifting / lowering means 40. On the other hand, it is necessary to position the unit body 10UB with respect to the lower printing surface (the outer peripheral surface of the drum 5) at the lower printing position.

In order to enable the unit body 10UB to move up and down while regulating the position of the unit body 10UB in the main scanning direction and the sub-scanning direction by using the elevating means 40 and elevating guide means including a plurality of guide rollers R1, As shown in FIG. 7, it is firmly attached to the lifting guide means.

That is, the unit body 10UB is the same as that shown in FIG.
As shown in (1), before (front) and after (R) the head holding members 60F, 60 before being screwed and fixed to the unit body 10UB.
The base holes 63F and 63R provided in the R
0 (support plate 57) is fitted to the fixed shaft 55 attached to the bosses 51F, 51R from both sides in the X direction, and thereafter, spacers 56, 56 are interposed between the carrier side plates 53, 53 and the bosses 51F, 51R. And set screws 56S, 56S
By being fastened with, they are integrally attached and fixed to the carrier 50 (50B). 1F and 1R are cases before and after the main body 1 is formed.

[0015]

However, in this trial example, the elevating means 40 and the elevating guide means must be sophisticated and high-grade processed and assembled without play. Therefore, not only is the structure complicated and the cost is easily increased, but also the direct or indirect vibration from the lifting / lowering means 40 side can be transmitted to the supported unit body 10UB. The printing quality or / and the printing quality in the sub-scanning direction is deteriorated. It is estimated that the more the rotation speed of the drum 5 is further increased to achieve higher printing speed, the more the printing speed becomes apparent.

A first object of the present invention is to provide an ink jet printer which does not transmit a vibration in a main scanning direction or a sub scanning direction from an elevating means side to a unit body including a nozzle head at a lower printing position. . A second object is to provide an ink jet printer capable of moving up and down between a lower printing position and an upper non-printing position while accurately maintaining the position regulation of the unit body in the main scanning direction and the sub scanning direction.

[0017]

According to the present invention, the lifting means is formed so as to be able to move up and down while accurately regulating the position in the main scanning direction and the sub-scanning direction in cooperation with the lifting guide means. In the printing position, the unit main body is separated from the elevating means and the elevating guide means and held by the stationary head print position holding means, and at this time, the position regulating function of the elevating guide means in the main scanning direction and / or the sub-scanning direction is released. The position regulation in the main scanning direction is performed by bringing the unit body into contact with an elastic positioning member on the stationary side capable of absorbing vibration by using an urging force. It is formed so that it can be used on the holding means side.

That is, according to the first aspect of the present invention, a nozzle head having a large number of ink jet nozzles arranged in the main scanning direction with respect to a printing surface is incorporated in a unit main body, and this unit main body is mounted in an axial direction orthogonal to the printing surface. A portion between the lower printing position and the upper non-printing position is formed so as to be able to move up and down along the raising and lowering guide means capable of regulating the position in the main scanning direction and the sub-scanning direction by the raising and lowering means. A unit body formed such that a roller guide surface to be formed and a guide roller for regulating a position in the main scanning direction on the unit body side do not come into contact with each other at a lower printing position, and the head printing position holding unit holds the unit at a lower printing position. Is formed to allow displacement in the main scanning direction,
Further, the ink jet printer is formed such that the unit main body held at the lower printing position by the head printing position holding means can be brought into contact with the stationary-side elastic positioning member by using the urging force in the main scanning direction.

In this invention, the unit main body is lowered to the lower printing position along the elevation guide means capable of regulating the position in the main scanning direction and the sub-scanning direction, and is held by the head printing position holding means. Then, the roller guide surface forming a part of the elevating guide means and the guide roller for regulating the position in the main scanning direction on the unit main body side come out of contact with each other, so that the head printing position holding means holds the unit main body in the main scanning direction. Allow displacement. In this state, the unit main body is urged in the main scanning direction and comes into contact with the stationary-side elastic positioning member. In other words, the position of the unit body in the main scanning direction is restricted by the elastic positioning member which is separated from the elevation guide means in the main scanning direction and capable of absorbing vibration.

That is, since the vibration in the main scanning direction from the lifting / lowering means is not transmitted to the unit body including the nozzle head held at the lower printing position by the stationary head printing position holding means, the printing surface is not transmitted from the nozzle head. If ink is ejected to the printer for printing, accurate printing without displacement in the main scanning direction can be performed.

According to a second aspect of the present invention, a nozzle head having a large number of ink jet nozzles arranged in the main scanning direction with respect to a printing surface is incorporated in a unit main body, and this unit main body is mounted in an axial direction orthogonal to the printing surface. A part between the lower printing position and the upper non-printing position is formed so as to be able to move up and down along the raising and lowering guide means capable of regulating the position in the main scanning direction and the sub-scanning direction by the raising and lowering means, and a part of the raising and lowering guide means is formed. The roller guide surface and at least a part of the guide roller for regulating the position in the sub-scanning direction on the unit body side are formed so as not to be in contact with each other at the lower print position, and the head print position holding means is at the lower print position. This is an inkjet printer formed so that the position of the held unit body in the sub-scanning direction can be regulated.

In this invention, the unit main body is lowered to the lower printing position along the elevation guide means capable of regulating the position in the main scanning direction and the sub-scanning direction, and is held by the head printing position holding means. Then, the roller guide surface forming part of the elevating guide means and the guide roller for regulating the position in the sub-scanning direction on the unit main body side come out of contact with each other, so that the head print position holding means holds the unit main body in the sub-scanning direction. Allow displacement. That is, the unit body is separated from the elevation guide means in the sub-scanning direction, and the position in the sub-scanning direction is regulated by the head print position holding means.

That is, since the vibration from the sub-scanning direction of the lifting / lowering means is not transmitted to the unit body including the nozzle head held at the lower printing position by the stationary head printing position holding means, the printing surface from the nozzle head is not transmitted. If ink is ejected to the printer for printing, accurate printing without displacement in the sub-scanning direction can be performed.

According to a third aspect of the present invention, a nozzle head having a large number of ink jet nozzles arranged in the main scanning direction with respect to a printing surface is incorporated in a unit main body, and this unit main body is mounted in an axial direction orthogonal to the printing surface. A part between the lower printing position and the upper non-printing position is formed so as to be able to move up and down along the raising and lowering guide means capable of regulating the position in the main scanning direction and the sub-scanning direction by the raising and lowering means, and a part of the raising and lowering guide means is formed. The roller guide surface and the guide roller for regulating the position in the main scanning direction on the unit body side are in non-contact at the lower printing position, and at least a part of the guide roller and the roller guide surface for regulating the position in the sub-scanning direction are lower. The main scanning direction of the unit body formed so as to be non-contact at the side printing position and held by the head printing position holding means at the lower printing position The unit body held in the lower printing position by the head printing position holding means is formed on the stationary side by using the urging force in the main scanning direction. This is an ink jet printer formed so as to be able to contact the elastic positioning member.

In this invention, the unit main body is lowered to the lower printing position along the elevation guide means capable of regulating the position in the main scanning direction and the sub scanning direction, and is held by the head printing position holding means. Then, the roller guide surface forming a part of the elevating guide means and the guide roller for regulating the position in the main scanning direction on the unit main body side come out of contact with each other, so that the head printing position holding means holds the unit main body in the main scanning direction. Allow displacement.

Further, the roller guide surface which forms a part of the elevating guide means and the guide roller for regulating the position in the sub-scanning direction on the unit main body side are not in contact with each other, and the head print position holding means makes the holding unit main body hold. Displacement in the sub-scanning direction is allowed.

In this state, the unit body is urged in the main scanning direction and comes into contact with the stationary-side elastic positioning member. That is, the unit main body is separated from the elevating guide means in the main scanning direction and the sub-scanning direction, and the position in the main scanning direction is regulated by an elastic positioning member capable of absorbing vibration, and the position in the sub-scanning direction is regulated by the head printing position holding means. Is done.

That is, since vibrations in the main scanning direction and the sub-scanning direction from the lifting / lowering means are not transmitted to the unit body including the nozzle head held at the lower printing position by the stationary head printing position holding means, If printing is performed by ejecting ink from the head to the printing surface, accurate printing can be performed without displacement in the main scanning direction and the sub-scanning direction.

Further, according to a fourth aspect of the present invention, there is provided a roller guide surface for regulating the position in the main scanning direction, which forms a part of the elevating guide means, and a concave portion which is depressed outward is provided. This is an ink jet printer formed so that a guide surface is not in contact with a lower printing position.

In this invention, when the unit main body is held by the head printing position holding means at the lower printing position, the guide roller forming the elevating guide means corresponds to the concave portion of the roller guide surface. That is, the guide roller and the roller guide surface are not in contact with each other at the lower printing position by using the concave portion. Therefore, in addition to providing the same functions and effects as in the first and third aspects of the present invention, the position restriction and restriction release functions in the main scanning direction can be realized at a low cost with a simple structure.

Further, according to a fifth aspect of the present invention, there is provided a roller guide corresponding to a lower guide roller for regulating a position in the sub-scanning direction on the unit body side which forms a part of the elevating guide means at the lower printing position. This is an ink jet printer in which a surface is curved outward and a lower guide roller is formed so as not to contact a roller guide surface curved outward at a lower printing position.

In this invention, the roller guide surface corresponding to the lower guide roller for regulating the position in the sub-scanning direction, which forms a part of the elevating guide means, has an outwardly curved shape at the lower print position. Therefore, in addition to providing the same functions and effects as the inventions of the second and third aspects, the position restriction and restriction release functions in the sub-scanning direction can be realized at a low cost with a simple structure.

[0033]

Embodiments of the present invention will be described below with reference to the drawings. The basic configuration and functions of this inkjet printer are the previously proposed printers (Figs. 5 and 6).
However, as shown in FIGS. 1 to 4, the lifting / lowering means 40 is moved in the main scanning (X) direction and the sub-scanning direction (R direction, in cooperation with the lifting / lowering guide means). (Specifically, a direction perpendicular to the X direction in the horizontal plane) is formed so as to be capable of ascending and descending while accurately regulating the position. At the lower printing position PP, the unit body 10UB is separated from the ascending and descending means 40 and the ascending and descending guide means so as to be stationary. The print head is held by the head print position holding means 30. At this time, the position regulating function of the elevation guide means in the main scanning direction and / or the sub-scanning direction is released, and the position regulation in the main scanning direction is performed by using the urging force of the unit body 10UB. It is formed so as to be brought into contact with the stationary-side elastic positioning member 70 capable of absorbing vibration, and the sub-scanning direction position regulating function can be exerted on the stationary-side head printing position holding means 30 side. To have.

In other words, depending on the printing mode or the like, it is possible to selectively employ either the avoidance of vibration transmission in the main scanning direction or the avoidance of vibration transmission in the sub-scanning direction from the lifting / lowering means 40 side. In this embodiment, both are employed. A description will be given of the case in which this is done.

Parts common to those in the case of the previously proposed printer (FIGS. 5 to 8) are denoted by the same reference numerals, and description thereof will be simplified or omitted.

In FIG. 1, a three-point support mechanism 30 forming the head print position holding means prints on one (front) side of the printing surface (drum 5) in the main scanning direction (X direction: perpendicular to the paper surface). The two sets of unit body side engaging portions 20 (and 2) that are displaced in the surface feed direction (R direction)
1) and the stationary side locking portion 31F (and 32F), and a pair of unit body side engaging portion 22 and stationary side locking portion 33R disposed on the other (rear) side.

Here, the locking portions 31F, 32F, 33R
Is formed of a round shaft member, the engaging portions 20 and 22 have a V-shape opened downward, and the engaging portion 21 has a flat surface shape. In other words, the head printing position holding means (30) can hold the held unit body 10UB in a horizontal state, allow relative displacement of the unit body 10UB in the main scanning direction, and regulate the position in the sub-scanning direction. .

A pair of front and rear head support means 60F, 6 whose base ends are attached and fixed to the carrier 50 shown in FIGS.
0R has a base-side support portion 6 having a hole shape (a V-shaped lower portion).
1F and a front-side support portion 62F having a flat surface shape are provided, and the front and rear plates 17F, 17F of the unit body 10UB are provided.
The R is provided with two round shaft members projecting in the X direction, that is, a distal-side engaging element 12F and a proximal-side engaging element 11F.

When the unit body 10UB is at the lower printing position shown in FIG.
The UB is separated from the carrier 50 to allow the head print position holding means 30 to shift the position regulating function. On the other hand, when the elevating means 40 (carrier 50) is raised, the head support means 60F, 60R (61F, 62F) engages with the unit main body 10UB (11F, 12F), and can raise the unit main body 10UB.

The elevating guide means comprises a unit body 10UB.
In this embodiment, the ascent / descent guide is performed while regulating the position in the main scanning direction and the sub-scanning direction.
It has a divided structure.

That is, the first elevating guide means for regulating the position in the sub-scanning direction, the unit body 10UB and the head supporting means 60F on the carrier 50 side at the lower printing position.
And a second elevating guide means for regulating the position of the unit main body 10UB in the main scanning direction with respect to the carrier 50 at the time of relative movement with respect to the carrier 60R in the main scanning direction.

The first elevating guide means comprises a pair of left and right roller guide surfaces 47F, 47R, each of which comprises a guide roller R2, R3 contacting from the right in FIG. 1 and a lower guide roller R4 contacting from the left. Roller guide surfaces 47F, 47R corresponding to the lower guide rollers R4, R4 for regulating the position in the sub-scanning direction, which form a part of the elevating guide means, are composed of three-point roller guide mechanisms having excellent operability. Shape (47R)
R).

That is, the guide rollers R4 and R4 are
In the upper non-printing position shown in FIG.
7R, but separates from the roller guide surfaces 47F, 47R (47RR, 47RR) at the lower printing position shown in FIG. The other guide rollers R2 and R3 may be kept in contact. When the lower guide rollers R4 and R4 are separated, the unit body 10 is moved by the swinging operation using the upper fulcrum.
This is because the displacement of the UB in the sub-scanning direction can be allowed. However, all the guide rollers may be formed so as not to contact.

The second lifting / lowering guide means includes guide rollers R5 and R6 which come into contact with the left carrier-side roller guide surface 57F shown in FIG. 2 from inside and a guide roller R7 which comes into contact with the right carrier-side roller guide surface 57R from inside. And a three-point roller guide mechanism.

When the unit body 10UB is at the upper non-printing position shown in FIG. 4, the two guide rollers R5, R6
Is in contact with the inner flat surface 57FS of the roller guide surface 57F, and the right guide roller R7 is in contact with the inner flat surface 57RS of the roller guide surface 57R to regulate the position of the main unit 10UB in the main scanning direction. The upper non-printing position is not limited to one position in the vertical direction.

However, when the unit body 10UB is at the lower non-printing position shown in FIG.
5, R6 are opposed to the concave portions 57FSC1 and 57SFC2 recessed outside the roller guide surface 57F, so that they do not contact the roller guide surface. Also, the right guide roller R7
Is a concave portion 57RS dented outside the roller guide surface 57R.
Since the roller guide surface is opposed to C1, the roller guide surface is not contacted. That is, the second lifting guide means is formed so as to allow the displacement of the unit main body 10UB held in the lower printing position by the head printing position holding means (30) in the main scanning direction.

Here, on the lower surface side of the unit body 10UB, a switching lever 26 (including a pressing roller 29 rotatable about a support shaft 28) and a spring that can rotate about a fulcrum 27 shown in FIG. SP is provided, and this urging means (S
The unit main body 10UB is urged in the main scanning direction (from left to right in FIG. 2) by using the urging force of P) to be formed so as to be able to abut against the stationary-side elastic positioning member (for example, a rubber plate) 70. It is. The nozzle unit 10 (10C, 10C)
M, 10Y, and 10K) may be formed so as to be able to be urged.

In this embodiment, the unit main body 10UB is lowered to the lower printing position PP along the ascending and descending guide means capable of regulating the positions in the main scanning direction and the sub-scanning direction, as shown in FIGS. Is held by the print position holding means (30).

Then, the roller guide surfaces 57F (57FS) and 57R (57R) forming a part of the elevation guide means
RS) and the guide rollers R5, R6, and R7 for regulating the position in the main scanning direction on the unit body 10UB side are out of contact with each other, and the displacement of the unit body 10UB held by the head printing position holding means (30) in the main scanning direction. Tolerate.

In this state, the unit body 10UB is urged in the main scanning direction and comes into contact with the stationary-side elastic positioning member 70. In other words, the position of the unit main body 10UB in the main scanning direction is separated from the elevating guide means in the main scanning direction and is regulated by the elastic positioning member 70 capable of absorbing vibration. The elastic positioning member 70 may be fixedly disposed at the same location, or may be formed to move to a predetermined location when the main unit 10UB is lowered to the lower printing position.

That is, since the vibration in the main scanning direction of the lifting / lowering means 40 is not transmitted to the unit body 10UB including the nozzle head 10 held at the lower printing position by the stationary-side head printing position holding means (30), If printing is performed by ejecting ink from the nozzle head to the printing surface, accurate printing without displacement in the main scanning direction can be performed.

When the unit main body 10UB is lowered to the lower printing position along the elevating guide means capable of regulating the position in the main scanning direction and the sub-scanning direction and is held by the head printing position holding means (30). , A roller guide surface 47F forming a part of the elevating guide means and the unit body 10
The guide roller R4 for regulating the position in the sub-scanning direction on the UB side does not come into contact, and the displacement of the unit body 10UB held in the head printing position holding means (30) in the sub-scanning direction is allowed.

That is, the unit body 10UB is separated from the elevation guide means in the sub-scanning direction, and the position in the sub-scanning direction is regulated by the head print position holding means (30). Therefore, since vibration in the sub-scanning direction on the side of the lifting / lowering means 40 is not transmitted to the unit main body 10UB, accurate printing without displacement in the sub-scanning direction can be performed.

Thus, the unit body 1 including the nozzle heads 10C, 10M, 10Y and 10K held at the lower printing position by the stationary head printing position holding means (30).
Since the vibration in the main scanning direction and the sub-scanning direction from the lifting / lowering means 40 side is not transmitted to 0UB, if the ink is ejected from the nozzle head to the printing surface and printing is performed, there is no displacement in the main scanning direction and the sub-scanning direction. You can print accurately.

Further, roller guide surfaces 57FS, 57 for regulating the position in the main scanning direction, which form a part of the elevating guide means.
Recessed concave portions 57FSC1, 57FS provided in RS
C2, using 57RSC1, the guide roller R
5, R6, R7 and the roller guide surfaces 57FS, 57RS are formed so as to be out of contact with each other at the lower printing position. Therefore, the position control and restriction release function in the main scanning direction can be realized at a low cost with a simple structure. it can.

Further, a roller guide surface 47 corresponding to the lower guide roller R4 for regulating the position in the sub-scanning direction on the unit body 10UB forming a part of the elevating guide means.
Since R has an outwardly curved shape (47RR, 47RR) and the lower guide rollers R4, R4 are formed so as not to contact the roller guide surfaces (47F, 47R) at the lower printing position. The position restriction and restriction release function in the sub-scanning direction can be realized at a low cost with a simple structure.

[0057]

According to the first aspect of the present invention, the elevating guide means which can regulate the position in the main scanning direction and the sub-scanning direction of the unit body between the lower printing position and the upper non-printing position by the elevating means. The roller guide surface of the elevating guide means and the guide roller for regulating the position in the main scanning direction on the unit body side are not in contact with each other at the lower printing position and the head printing position at the lower printing position. The unit main body held by the holding means is formed so as to allow displacement in the main scanning direction, and the unit main body held at the lower printing position by the head printing position holding means is utilized by using the urging force in the main scanning direction. Since it is an ink jet printer formed so as to be able to contact the stationary elastic positioning member, it is held at the lower printing position by the stationary head print position holding means. The vibration in the main scanning direction of the unit body lifting means side including the nozzle head is not transmitted. Therefore, if printing is performed by ejecting ink from the nozzle head to the printing surface, accurate printing without displacement in the main scanning direction can be performed.

Further, according to the second aspect of the present invention, the elevating guide means capable of regulating the position of the unit body between the lower printing position and the upper non-printing position in the main scanning direction and the sub scanning direction by the elevating means. The roller guide surface of the elevating guide means and at least a part of the guide rollers for regulating the position in the sub-scanning direction on the unit body side are in non-contact at the lower printing position and the lower printing position Since the inkjet printer is formed so that the position in the sub-scanning direction of the unit body held by the head printing position holding means can be regulated, the nozzle head held at the lower printing position by the stationary head printing position holding means can be used. Vibration in the sub-scanning direction on the lifting / lowering means side is not transmitted to the unit main body including. Therefore, if printing is performed by ejecting ink from the nozzle head to the printing surface, accurate printing without displacement in the sub-scanning direction can be performed.

According to the invention of claim 3, according to claim 1,
And an ink jet printer having the same configuration as that of the invention of claim 2, so that the unit body including the nozzle head held at the lower printing position by the stationary head printing position holding device is moved from the lifting device side to Are not transmitted in the main scanning direction and the sub-scanning direction. Therefore, if printing is performed by discharging ink from the nozzle head to the printing surface, accurate printing can be performed without positional displacement in the main scanning direction and the sub-scanning direction.

Further, according to the fourth aspect of the present invention, the guide roller and the roller are formed by utilizing an outwardly concave portion provided on the roller guide surface for regulating the position in the main scanning direction which forms a part of the elevating guide means. Claim 1 because the guide surface is formed so as not to contact the lower printing position.
In addition to the effects similar to those of the inventions according to the third aspect, the position restriction and restriction release functions in the main scanning direction can be realized at a low cost with a simple structure.

According to the fifth aspect of the present invention, the roller guide surface corresponding to the lower guide roller for regulating the position in the sub-scanning direction on the unit body side forming a part of the elevating guide means at the lower print position. Is bent outward, and the lower guide roller is formed so as not to be in contact with the roller guide surface at the lower printing position, so that it is the same as in each of the inventions of claims 2 and 3. In addition to achieving the effect, the position restriction and restriction release functions in the sub-scanning direction can be realized at a low cost with a simple structure.

[Brief description of the drawings]

FIG. 1 is a front view for explaining a case where a unit main body according to an embodiment of the present invention is at a lower printing position.

FIG. 2 is a right side view of the same as viewed from an arrow AA in FIG.

FIG. 3 is a front view for explaining a case where the unit main body is at an upper printing position.

FIG. 4 is a right side view of the same viewed from an arrow BB of FIG. 2;

FIG. 5 is a schematic front view for explaining the overall configuration of the previously proposed inkjet printer.

FIG. 6 is also a view for explaining the elevating operation of the unit body.

FIG. 7 is a plan view for explaining a state in which the unit body is supported by a head support member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 5 Drum (printing surface) 10C, 10M, 10Y, 10B Nozzle head 10U Nozzle unit 10UB Unit main body 11 Base end engaging element 12 Front end engaging element 20, 21 Unit main body side engaging part 22 Unit main body side engaging part 26 switching lever SP spring 29 pressing roller 30 three-point support mechanism (head printing position holding means) 31, 32 stationary side locking part 33 stationary side locking part 40 elevating means 47 roller guide surface R2, R3, R4 guide roller 50 carrier 57 Roller guide surface 57FS, 57RS Inner plane 57FSC1, 57SFC2 Recess R5, R6, R7 Guide roller 60 Head support member 61 Base side support portion 62 Front side support portion 63 Base end portion locking portion 70 Elastic positioning member 81 Feeding means 88 Ink supply means 90 Maintenance means 95 Motion means R rotational direction (sub scanning direction) X main scanning direction Y axis PP lower side printing perpendicular to the printing surface position NPP upper nonprinting position

Claims (5)

[Claims] 1. A nozzle head having a large number of ink jet nozzles arranged in a main scanning direction with respect to a printing surface is incorporated in a unit body, and the unit body is mounted on a lower printing position and an upper side in an axial direction perpendicular to the printing surface. A roller guide surface and a unit that are formed so as to be able to move up and down along a raising and lowering guide means capable of regulating the positions in the main scanning direction and the sub-scanning direction by the raising and lowering means between the non-printing position and a part of the raising and lowering guide means The guide roller for regulating the position in the main scanning direction on the main body side is formed so as not to be in contact with the lower printing position, and the head printing position holding means controls the displacement in the main scanning direction of the unit main body held in the lower printing position. The unit body, which is formed to be acceptable and held at the lower printing position by the head printing position holding means, is attached in the main scanning direction. An ink jet printer formed so as to be able to contact a stationary side elastic positioning member by using force. 2. A nozzle head having a large number of ink jet nozzles arranged in a main scanning direction with respect to a printing surface is incorporated in a unit main body, and the unit main body is mounted on a lower printing position and an upper side in an axial direction perpendicular to the printing surface. A roller guide surface and a unit main body, which are formed so as to be able to move up and down along a raising and lowering guide means capable of regulating the position in the main scanning direction and the sub-scanning direction by the raising and lowering means between the non-printing position and form a part of the raising and lowering guide means. The sub-scanning of the unit main body, which is formed so that at least a part of the guide rollers for regulating the position in the sub-scanning direction does not contact at the lower printing position, and the head printing position holding means holds at the lower printing position. An ink jet printer formed so that the position in the direction can be regulated. 3. A nozzle head having a large number of ink jet nozzles arranged in the main scanning direction with respect to a printing surface is incorporated in a unit main body, and the unit main body is mounted on a lower printing position and an upper side in an axial direction orthogonal to the printing surface. A roller guide surface and a unit main body, which are formed so as to be able to move up and down along a raising and lowering guide means capable of regulating the position in the main scanning direction and the sub-scanning direction by the raising and lowering means between the non-printing position and form a part of the raising and lowering guide means The guide roller for regulating the position in the main scanning direction is not in contact with the lower printing position, and at least a part of the guide roller for regulating the position in the sub-scanning direction is not in contact with the roller guide surface in the lower printing position. The unit main body held in the lower printing position by the head printing position holding means is allowed to displace in the main scanning direction and is The position in the scanning direction is regulated so that the unit body held at the lower printing position by the head printing position holding means can be brought into contact with the stationary side elastic positioning member by using the urging force in the main scanning direction. The formed inkjet printer. 4. A roller guide surface for regulating the position in the main scanning direction, which forms a part of the elevation guide means, is provided with a concave portion which is depressed outward, and the guide roller and the roller guide surface are printed on the lower side by utilizing this concave portion. The ink jet printer according to claim 1, wherein the ink jet printer is formed so as to be non-contact at the position. 5. A roller guide surface corresponding to a lower guide roller for regulating a position in the sub-scanning direction on the unit main body side, which forms a part of the elevating guide means at the lower print position, has an outwardly curved shape. 4. The ink jet printer according to claim 2, wherein the lower guide roller is formed so as not to contact the outwardly curved roller guide surface at the lower printing position.