JP2007160532A - Liquid ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid ejector, the simple constitution of which restrains a backlash from being caused at a level of several tens of microns when a carriage reciprocates in a main scanning direction. <P>SOLUTION: In the carriage 23, a bearing part 41 is formed as a part corresponding to a main guide rod 21, and a carriage sliding part 42 is formed as a part corresponding to an auxiliary guide rod 22. The main guide rod 21 is loosely fitted into the bearing part 41. The carriage sliding part 42, which is formed in such a shape as to make a predetermined angle θ with respect to the horizontal direction of the carriage 23, abuts on the auxiliary guide rod 22 in a place with the predetermined angle. Thus, the main guide rod 21 is spontaneously brought into pressure contact in one direction of the bearing part 41 by a sliding force and the self-weight of the carriage 23. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus, and more particularly to a liquid ejecting apparatus that performs printing by performing reciprocal sliding of a carriage in a main scanning direction.

  The following are known as techniques for a liquid ejection apparatus such as an ink jet recording apparatus.

  Japanese Patent Application Laid-Open No. 2004-228688 proposes an inkjet image forming apparatus that raises the productivity and reliability of the apparatus by detecting cartridge removal during printing, determining the remaining amount of ink, and performing a stop operation.

Further, in Patent Document 2, slip occurs between the conveyance belt and the driving roller, the image quality is deteriorated, the electrostatic adsorption force cannot be efficiently obtained due to the floating of the paper, and the belt driving load is caused by a roller that holds the paper. Ink jet image forming apparatuses have been proposed that suppress the belt stop position from decreasing due to an increase in the belt.
JP 2004-358733 A JP 2004-238111 A

  In such a liquid ejecting apparatus, the carriage on which the print head is mounted reciprocates in the main scanning direction. This carriage appears to move smoothly at first glance, but in reality, vibrations and rattling occur vertically and horizontally at a level of several tens of microns.

  When vibration at a level of several tens of microns occurs in a carriage on which a print head that performs printing by ejecting ink is mounted, the print image quality is directly affected and the image quality is deteriorated. Therefore, a very severe accuracy is required for the positional accuracy of the reciprocating motion in the main scanning direction. In other words, suppressing vibration and rattling that occurs in the carriage is an issue of preventing image quality deterioration.

  However, the technologies described in Patent Documents 1 and 2 do not consider this point at all.

  The present invention has been proposed in view of the above points, and suppresses rattling at a level of several tens of microns, which occurs when the carriage of the liquid ejection apparatus reciprocates in the main scanning direction, with a simple apparatus configuration. An object is to provide a liquid ejection device.

  According to a first aspect of the present invention, there is provided a liquid ejecting apparatus in which a carriage on which a print head is mounted reciprocally slides in a main scanning direction to perform printing, and the carriage includes a first guide member horizontally mounted and a carriage The first guide member is slidably supported by a second guide member, and the first guide member has a cylindrical shape, and is loosely fitted to a bearing portion formed on the carriage, and the second guide member is a cylinder It has a shape and is in contact with a surface having a predetermined angle with respect to the horizontal direction formed on the lower surface of the carriage.

  According to a second aspect of the present invention, there is provided a liquid ejecting apparatus in which a carriage on which a print head is mounted reciprocally slides in a main scanning direction to perform printing, and the carriage includes a first guide member horizontally mounted and The first guide member is slidably supported by a second guide member, and the first guide member has a cylindrical shape, and is loosely fitted to a bearing portion formed on the carriage, and the second guide member has an upper surface Has a plate shape having a predetermined angle with respect to the horizontal direction, and the upper surface is in contact with the contact portion formed on the carriage.

  According to a third aspect of the present invention, in the liquid ejection apparatus according to the first or second aspect, the predetermined angle is not less than 5 degrees and not more than 45 degrees.

  According to the present invention, since the second guide member is in contact with a surface having a predetermined angle in the horizontal direction formed on the lower surface of the carriage, a sliding force is generated on the carriage. The first guide member is naturally pressed in one direction of the bearing portion by the sliding force and the weight of the carriage, so that a clearance necessary for sliding is ensured and unnecessary play is eliminated and stable. In this state, the carriage can be slid.

  Hereinafter, a liquid ejection apparatus according to the present invention will be described according to an embodiment. In the following embodiments, description will be made using an ink jet recording apparatus which is one type of liquid ejection apparatus.

<Inkjet recording apparatus>
With reference to FIG. 1, the configuration of the ink jet recording apparatus of this embodiment will be described. FIG. 1 shows the ink jet recording apparatus 1 of this embodiment as viewed from the side.

  The ink jet recording apparatus 1 includes a paper feed tray 2, a manual feed tray 3, a paper discharge tray 4, a paper feed roller 5, a friction pad 6, a paper feed roller 7, an electrostatic conveyance belt 8, and a charging charger 9. A paper discharge roller 10 and a printing device 20.

  The paper feed tray 2 is a tray for storing the recording paper 11. The recording paper stored here is conveyed and fed at the time of printing output. Note that the ink jet recording apparatus 1 of FIG. 1 has two paper feed trays 2, and each of the paper feed trays 2 stores recording papers of different sizes.

  The manual feed tray 3 is a tray for manually feeding the recording paper 11. The paper discharge tray 4 is a tray for discharging the printed recording paper 11.

  The paper feed roller 5 is a roller for transporting and feeding the recording paper 11 stored in the paper feed tray 2. The friction pad 6 is a pad provided at a position facing the paper feed roller 5 and applies a frictional force so that the paper feed roller 5 does not feed a plurality of recording papers 11 at a time. The recording paper 11 is separated and conveyed one by one by the paper feed roller 5 and the friction pad 6.

  The paper feed roller 7 is a roller provided on the transport path of the recording paper 11 and defines the paper feed angle of the transported recording paper 11.

  The charging charger 9 charges the surface of the electrostatic conveyance belt 8.

  The electrostatic conveyance belt 8 conveys the recording paper 11 to the lower side of the print head 24 of the printing apparatus 20. Since the surface of the electrostatic conveyance belt 8 is charged by the charging charger 8, the recording paper 11 is sucked and conveyed. Therefore, there is no inconvenience that the recording paper 11 is displaced from the print head 24.

  The printing device 20 performs printing / printing processing on the recording paper 11. The printing device 20 will be described in detail later.

  The paper discharge roller 10 is a roller for guiding the recording paper 11 printed by the printing apparatus 20 to the paper discharge tray 4.

<Printing device>
Next, the printing apparatus 20 will be described with reference to FIG. FIG. 2 shows the printing apparatus 20 of this embodiment as viewed from above.

  The printing apparatus 20 includes a main guide rod 21, a sub guide rod 22, a carriage 23, a print head 24, an ink supply tube 25, a main tank 26, a toothed belt 27, a drive motor 28, and a drive motor pulley. 29 and a driven pulley 30.

  The main guide rod 21 and the sub guide rod 22 are cylindrical rods that extend horizontally inside the printing apparatus 20 and support the carriage 23. Both guide rods are stretched over in such a manner that the longitudinal direction thereof coincides with the main scanning direction.

  The carriage 23 is slidably supported by the main guide rod 21 and the sub guide rod 22, and reciprocally slides in the longitudinal direction of both guide rods, that is, the main scanning direction.

  The carriage 23 is provided with a print head 24 for each color that performs printing by ejecting ink droplets of cyan (C), magenta (M), yellow (Y), and black (K). The print head 24 includes a head unit that ejects ink droplets downward and a sub tank that holds ink.

  The sub-tank of the print head 24 is connected to the main tank 26 via an ink supply tube 25 composed of a bundle of four pipes, whereby ink of a color corresponding to the sub-tank of each color print head 24 is supplied from the main tank 26. Is done.

  As an ink ejection method, a piezoelectric type method in which ink is ejected from an ejection port by pressing a part of an ink flow path using an electromechanical conversion element such as a piezoelectric element, or film boiling by a heating resistor is used. Although there is a bubble type system in which ink is ejected by generating bubbles and pressurizing ink, the ink jet recording apparatus 1 of the present embodiment may be a print head 24 using any ink ejection system.

  The carriage 23 is fixed to a toothed belt 27 stretched on a drive motor pulley 29 and a driven pulley 30 directly connected to the drive motor 28. The toothed belt 27 is provided so that the belt direction is parallel to the main guide rod 21 and the sub guide rod 22, and the carriage 23 reciprocates in the main scanning direction according to the rotational drive of the drive motor 28.

<System configuration>
Next, with reference to FIG. 3, the system configuration of the inkjet recording apparatus 1 of the present embodiment will be described.

  The ink jet recording apparatus 1 includes a CPU 31, a ROM 32, a RAM 33, an NVRAM 34, an image memory 35, a printing device control unit 36, an external communication I / F 37, and an operation unit 38.

  A CPU (Central Processing Unit) 31 is a central processing unit and performs overall control of the inkjet recording apparatus 1. Specifically, a program stored in the ROM 32 is expanded in the RAM 33, and various processes such as data processing and arithmetic processing are executed in accordance with the expanded program.

  A ROM (Read Only Memory) 32 is a read-only nonvolatile memory, and stores various programs, data, parameters, and the like for the CPU 31 to perform various calculations and controls.

  A RAM (Random Access Memory) 33 is a memory in which programs and data can be freely written, and provides a working area necessary for the CPU 31 to execute various processes.

  An NVRAM (Nonvolatile RAM) 34 is a memory that stores adjustment values such as control and timing, registered copy mode settings, and the like. Since NVRAM is a non-volatile memory, the set value is retained even when the power of the inkjet recording apparatus 1 is turned off.

  The image memory 35 is a storage area for developing print data (data to be printed / printed) received from an external terminal.

  The printing device control unit 36 controls the operation of the printing device 20 of the inkjet recording apparatus 1. Specifically, the print head 24 and the drive motor of the printing apparatus 20 are formed so that the print data developed in the image memory 35 is formed on the recording paper 11 based on the count values output from the main scanning counter and the sub scanning counter. 28 is controlled.

  The external communication I / F 37 is an interface for connecting to an external terminal of the inkjet recording apparatus 1, and exchanges print data, auxiliary / control data, and the like.

  The operation unit 38 receives an operation input from the outside of the inkjet recording apparatus 1, specifically, an operation input from a user. The operation unit 38 is connected to an input device such as a liquid crystal touch panel 39.

<Carriage shape>
Next, with reference to FIG. 4, the shape of the carriage 23 of the inkjet recording apparatus 1 of the present embodiment will be described. FIG. 4 shows the configuration of the carriage 23 and its vicinity as viewed from the side. For the sake of simplification of explanation, unnecessary configurations are not shown.

  As shown in FIG. 4, a bearing portion 41 and a carriage slide portion 42 are formed on the lower surface of the carriage 23 as corresponding portions to the guide rod. The bearing portion 41 is supported by the main guide rod 21, and the carriage slide portion 42 is supported by the sub guide rod 22.

  The diameter of the bearing portion 41 is larger than the diameter of the main guide rod 21. Therefore, the main guide rod 21 is fitted into the bearing portion 41 with play (is loosely fitted).

  The carriage slide portion 42 has a shape having a predetermined angle θ with respect to the horizontal direction of the carriage 23, and is in contact with the sub guide rod 22 on a surface having this angle. Therefore, a sliding force (pressing force) in the horizontal direction due to the weight of the carriage 23 is generated in the carriage 23.

  Due to the sliding force and the weight of the carriage 23, the carriage 23 is in a state as shown in FIG. 5, that is, the main guide rod 21 is naturally pressed in one direction of the bearing portion 41. As a result, the carriage 23 is supported by the main guide rod 21 and the sub guide rod 22 in a stable state while securing a clearance necessary for sliding and eliminating unnecessary play.

<Effect>
In the ink jet recording apparatus 1 of the present embodiment, the carriage 23 can be slid in a stable state while eliminating the unnecessary play while ensuring the clearance necessary for sliding, so that high accuracy can be achieved with a simple configuration. A printing operation can be performed.

<Supplementary items>
Note that the angle θ with respect to the horizontal direction of the carriage slide portion 42 is set in a range greater than 0 ° and less than 90 ° according to the weight of the carriage 23, the scanning speed, and the material of the carriage slide portion 42.

  Note that the angle θ may be any value as long as it is greater than 0 ° and smaller than 90 °, but is particularly preferably a value between 5 ° and 45 °. The reason is that if the angle is 5 ° or less, there is a problem in terms of stable support by the guide rod, and if the angle is 45 ° or more, the function of supporting the weight of the two guide rods is hindered. It is.

<Other embodiments>
The configuration of the carriage 23 may be as shown in FIG. In FIG. 6, the sub guide rod 22 is a guide plate 43 made of a plate material, and the carriage slide portion 42 is an abutting portion 44 provided on the carriage 23 as compared with the above-described embodiment.

  As shown in the figure, the upper surface of the guide plate 43 has a shape having a predetermined angle θ with respect to the horizontal direction. Further, the contact portion 44 provided on the carriage 23 is in contact with a surface having an angle with respect to the horizontal direction of the guide plate 43. Accordingly, as in the above-described embodiment, a horizontal sliding force (pressing force) is generated in the carriage 23 due to its own weight.

  Due to the sliding force and the weight of the carriage 23, the main guide rod 21 is naturally pressed against the carriage 23 in one direction of the bearing portion 41. As a result, also in the ink jet recording apparatus 1 of the present embodiment, as in the case of the above embodiment, the carriage 23 is mainly in a stable state while ensuring a clearance necessary for sliding and eliminating unnecessary play. It is supported by the guide rod 21 and the sub guide rod 22.

  Accordingly, in the inkjet recording apparatus 1 of the present embodiment, the carriage 23 can be slid in a stable state while ensuring a clearance necessary for sliding and eliminating unnecessary play. Accurate printing operation can be performed.

  In addition, since the inkjet recording apparatus 1 of this embodiment uses a plate material (guide plate) instead of the sub guide rod, it is advantageous in terms of weight reduction and cost reduction as compared with the above embodiment. On the other hand, it is disadvantageous in that it is difficult to ensure the accuracy of parts such as the progress of surfaces and members related to sliding. Therefore, it is selected according to the specifications required for the inkjet recording apparatus 1.

  Further, the angle θ with respect to the horizontal direction of the guide plate 43 is a value in a range larger than 0 ° and smaller than 90 °, more preferably 5 ° or more and 45 ° or less, similarly to the range of θ in the above-described embodiment. . Since the reason for this range is the same as that described above, the description thereof is omitted here.

<Additional notes>
The above-described embodiment is merely an example of a preferred embodiment of the present invention, and is not intended to limit the embodiment of the present invention. Therefore, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, in the description of the above-described embodiment, an ink jet recording apparatus that performs printing by ejecting ink is described as an example of the liquid ejecting apparatus. However, the liquid ejecting apparatus is not limited to the ink jet recording apparatus. Absent.

  In the above embodiment, the printing apparatus adopting the ink supply method using the main tank and the sub tank is adopted. However, the present invention is not limited to this, and the ink supply method using the ink cartridge method can also be adopted. It is.

  Further, the technical content of the present invention, that is, the technical content that enables a stable sliding operation of an object supported on two axes, is not limited to the carriage of the liquid ejecting apparatus, but, for example, reciprocates on two axes at high speed. The present invention can also be applied to a device that moves.

It is a side view which shows the structure of an inkjet recording device. It is a top view which shows the structure of a printing apparatus. It is a figure which shows the system configuration | structure of an inkjet recording device. It is a figure which shows the shape of the side surface direction of a carriage. It is a figure for demonstrating the sliding force which acts on the self-weight of a carriage and a carriage. It is a figure which shows the shape of the carriage of other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 20 Printing device 21 Main guide rod 22 Sub guide rod 23 Carriage 41 Bearing part 42 Carriage slide part 43 Guide plate 44 Contact part

Claims (3)

A liquid ejecting apparatus in which a carriage carrying a print head slides back and forth in the main scanning direction and performs printing,
The carriage is slidably supported by a first guide member and a second guide member horizontally mounted in a horizontal direction,
The first guide member has a cylindrical shape, and is loosely fitted to a bearing portion formed on the carriage.
The liquid ejecting apparatus according to claim 1, wherein the second guide member has a cylindrical shape and is in contact with a surface formed at a lower surface of the carriage and having a predetermined angle with respect to a horizontal direction. A liquid ejecting apparatus in which a carriage carrying a print head slides back and forth in the main scanning direction and performs printing,
The carriage is slidably supported by a first guide member and a second guide member horizontally mounted in a horizontal direction,
The first guide member has a cylindrical shape, and is loosely fitted to a bearing portion formed on the carriage.
The second guide member has a plate shape with an upper surface having a predetermined angle with respect to a horizontal direction, and the upper surface is in contact with a contact portion formed on the carriage. .   The liquid ejecting apparatus according to claim 1, wherein the predetermined angle is not less than 5 degrees and not more than 45 degrees.

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