JP2000203041A - Print head maintenance mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost and size by forming a wiper part and a cap part integrally of an elastic member, abutting them against the elastic member when an ink cartridge is moved and deforming both parts to be displaced thereby simplifying the parts and mechanisms for wiping and capping. SOLUTION: A wiper part 14 is formed on the side opposite to a leg part 16 extending perpendicularly to the moving direction of an ink cartridge while a cap 15 is formed between them and they are shaped integrally by means of an elastic member 8, e.g. a rubber. The wiper part 14 comprises first and second wiper parts 141, 142 having knife edge parts 141a, 142a while the cap 15 is provided with a recess 19 having side walls 17, 18 and a protrusion piece 20 is formed integrally while facing the wiper part 141. The member 8 is deformed when the wiper part 141 moves further after abutting against the cartridge at a home position upon completion of printing. The head is thereby contained in the recess 19 and capped and when the wiper part 141 moves further, the head slides on the wiper part 141 a to perform wiping.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a print head maintenance mechanism provided in an ink jet type recording apparatus which performs printing by ejecting ink in an ink cartridge from a print head onto a recording medium.

[0002]

2. Description of the Related Art In an ink jet recording apparatus, ink is ejected from nozzles provided on a recording medium such as paper while the recording head scans the recording medium, and recording is performed on the recording medium.

In such a recording apparatus, when ink is ejected from the head, ink droplets and the like adhere to the nozzles, causing the nozzles to wet. In addition, in the printing process, water evaporates from the ink adhering to the recording medium, and the surroundings of the head become highly humid, and depending on temperature conditions, dew condensation may occur on the ink ejection surface.

When the ejection surface is wet or dewed, ink droplets or the like are unevenly attached to the ejection surface, ink is not ejected due to adhesion of paper powder to the ejection surface, or the ink ejection direction is reduced. Of the print image quality. Therefore, in order to prevent this, it is common practice to clean the head by sliding a wiper made of an elastic member such as rubber on the ejection surface of the head. This operation is called wiping.

On the other hand, when the printing apparatus is not used, if the print head is left in the air, the ejection in the nozzles becomes defective due to thickening and solidification of the ink in the nozzles. Therefore, it is common practice to cover the ink ejection surface of the print head with a cap member during non-printing to prevent the nozzles from drying. This operation is called capping.

[0006] The mechanism for performing the wiping and capping as described above is called a print head maintenance mechanism. An inkjet printer having such a print head maintenance mechanism is disclosed in, for example,
281255, JP-A-3-290259,
JP-A-4-307257, JP-A-8-26777
No. 0, JP-A-9-150522 and the like.

FIG. 8 is a perspective view showing an example of an ink jet printer having a conventional print head maintenance mechanism. In the figure, an ink jet printer 1 includes an ink carriage 2 which can move linearly reciprocally, and the ink carriage 2 holds an ink cartridge 4 having a print head 4a at a lower portion. In the process of being moved by the ink carriage 2, the ink cartridge 4 performs printing by ejecting ink from the print head 4 a onto the printing paper 3 as a recording medium.

The ink carriage 2 is held by a guide shaft 5 and a guide plate (not shown) laid between chassis side plates (not shown) so as to be able to linearly reciprocate, and is driven in a direction indicated by an arrow by a toothed drive belt 6 during printing. It is driven back and forth. Reference numeral 7 denotes a motor.
Is transmitted to the ink carriage 2 via the toothed drive belt 6.

As a transport mechanism for the printing paper 3, a platen roller (not shown) which is rotated by a motor (not shown) and transports the printing paper 3 is provided on the platen roller so as to be able to freely contact with and separate from the platen roller. Printing paper 3
, A driven tension roller (not shown) for assisting the conveyance of the print paper 3, a discharge roller (not shown) for discharging the print paper 3 by being rotationally driven by a motor (not shown), and And a driven paper ejection tension roller (not shown) that assists the paper ejection of the printing paper 3 with the printing paper 3 interposed between the paper ejection rollers and the paper ejection roller. These platen roller, tension roller, paper discharge roller, and paper discharge tension roller are bridged between chassis side plates and rotatably supported.

Reference numeral M denotes a print head maintenance mechanism, which includes a base 9 serving as a fixing member, a cap 10 held by a cap holder 11, and a wiper 12 held by a wiper holder 13.

The wiper 12 is made of an elastic member such as rubber,
As shown in FIG. 9, the distal end portion 12a is formed wide. The cap 10 is also made of an elastic member such as rubber, and is formed in a box shape as shown in FIG.
The cap 10 is fixed to a cylindrical cap holder 111 made of resin, and is movable vertically by a spring S with respect to the cap holder 112 made of resin.

In the above-described ink jet printer, when the print head 4a finishes printing on the printing surface of the printing paper 3, the printing paper 3 is discharged out of the printer 1 by a discharge roller or the like, and the ink carriage 2 is moved to the home position. Transfer operation to the cap position is started. That is, after the printing operation is completed, the ink carriage 2 on which the ink cartridge 4 is mounted is moved rightward in FIG. 8 by the toothed belt 6 driven by the motor 7, and the print head 4 a faces the cap 10. It is transported to the position.

In this movement process, the wiper holder 13 is moved upward by the action of a cam mechanism (not shown) interlocked with the ink carriage 2, and the tip 12 a of the wiper 12 is moved.
Is lifted to a position slightly higher than the surface of the print head 4a of the ink cartridge 4. As a result, when the print head 4a passes through the position of the wiper 12, the distal end portion 12a of the wiper 12 comes into slidable contact with the print head 4a by its elastic force, thereby cleaning the print head 4a.

Thereafter, when the ink carriage 2 moves further rightward, the cap holder 11 moves upward by the action of the cam mechanism described above, and when the ink carriage 2 comes to the end position, that is, the cap position, the cap 10 prints. The ink cartridge 4 covers the head 4a.
Abut. As a result, capping is performed, and drying of the print head 4a is prevented.

FIG. 11 schematically shows the wiping and capping operations described above. When the ink cartridge 4 moves rightward as shown in FIG. 3A and the print head 4a comes into contact with the wiper 12, the wiper 12 elastically deforms as shown in FIG.
(C), the tip 12a of the wiper 12 is moved to the lower surface (ink ejection surface) of the print head 4a.
And the wiping operation is performed. Thereafter, when the print head 4a of the ink cartridge 4 reaches the cap position, the cap 10 moves upward as shown in FIG. 4D, and the ink cartridge 4 covers the print head 4a as shown in FIG. 4, the capping operation is performed.

[0016]

In the above-described conventional ink jet printer, the wiper 12 and the cap 1 are used.
Since 0 is formed as a separate member, there arises a problem that the number of parts is increased and cost reduction is hindered. Also,
A cam mechanism or the like for driving the wiper 12 and the cap 10 in the vertical direction is required, which contributes to an increase in cost in conjunction with the increase in the number of parts, and a downsizing of the apparatus because a complicated mechanism is required. Above all, it was an obstacle.

An object of the present invention is to solve the above-mentioned problems and to reduce the cost by simplifying parts and mechanisms for wiping and capping, and to reduce the size of the apparatus. And

[0018]

In order to solve the above-mentioned problems, a print head maintenance mechanism according to the present invention comprises a wiper section for slidably contacting a print head for wiping, and a cap section for covering and capping the print head. Are formed integrally by an elastic member, and when the ink cartridge is moved, the cartridge comes into contact with the elastic member to elastically deform the member, thereby displacing the wiper portion and the cap portion, and the printing is performed by the wiper portion. The head is cleaned and the print head is covered with the cap.

In this way, since the wiper portion and the cap portion are integrally formed, only one member for wiping and capping is required. In addition, since wiping and capping are performed using the elastic deformation of the elastic member, a special mechanism for driving the wiper unit and the cap unit is not required.

The elastic member has a leg extending substantially perpendicular to the direction of movement of the ink cartridge, and a wiper portion is formed on a side opposite to the leg portion. A cap portion is formed therebetween, and the elastic member can be configured to be bent substantially at a right angle near the base of the leg portion and the cap portion by bringing the ink cartridge into contact with the wiper portion.

The wiper portion includes a first wiper portion protruding laterally with respect to the leg portion, and a second wiper portion protruding in a direction opposite to the first wiper portion. When the ink cartridge moves in the first direction, the cartridge contacts the first wiper portion, and when the ink cartridge moves in the second direction, the cartridge contacts the second wiper portion. it can.

Further, the cap portion may have a recess for accommodating the print head.

Further, the tip of the wiper portion can be shaped as a knife edge.

Further, the elastic member has a leg extending substantially perpendicular to the direction of movement of the ink cartridge, and a box-shaped cap is formed integrally with the leg, and the cap is formed integrally with the elastic member. Is upwardly surrounded by a wall, and an upper end surface of the wall is formed as a wiper portion that slides on a print head, and the leg portion is formed by bringing an ink cartridge into contact with a cap portion. Can be configured to elastically deform.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an example of a print head maintenance mechanism according to the present invention. The print head maintenance mechanism M includes a wiper unit 14 that slides on a print head of an ink cartridge described later to perform wiping, a cap unit 15 that covers the print head and performs capping, and a leg 16. The cap 14, the cap 15, and the leg 16 are integrally formed of an elastic member 8 such as rubber. Specifically, the elastic member 8 is made of a material such as an elastomer. As shown in FIG. 2, the elastic member 8 is provided inside the base 9 of the ink jet printer 1 such that the wiper portion 14, the cap portion 15, and the like protrude upward.

The leg 16 extends substantially perpendicular to the direction of movement of the ink cartridge 4 (the direction of the arrow in FIG. 2), and a wiper 14 is formed on the opposite side of the leg 16.
A cap 15 is formed between the leg 16 and the wiper 14.

The wiper section 14 includes a first wiper section 141 projecting laterally with respect to the leg section 16, and a second wiper section 142 projecting in a direction opposite to the first wiper section 141. The tip portions 141a and 142a of the wiper portions 141 and 142 are formed in a tapered knife edge shape.

A recess 19 having a pair of opposed side walls 17 and 18 is formed in the cap portion 15, and a projecting piece 20 facing the first wiper portion 141 with the recess 19 interposed therebetween. Is formed. This protruding piece 2
The length of 0 is substantially the same as the length of the first wiper portion 141, and extends in parallel with the first wiper portion 141.

The elastic member 8 having the above structure is provided at the base 21 of the cap part 15 and the leg part 16 by the notch 2.
2 so that it can be easily bent by elastic deformation near the base 21.

FIG. 2 shows an example of an ink jet printer using the above-mentioned elastic member 8 as a print head maintenance mechanism M, and the same parts as those in FIG. 2 except for the printhead maintenance mechanism M are the same as those in FIG. 8, and a detailed description thereof will be omitted.

In FIG. 2, when the print head 4a finishes printing on the printing surface of the printing paper 3, the printing paper 3 is discharged out of the printer 1 by a discharge roller or the like, and the ink carriage 2 on which the ink cartridge 4 is placed is placed. Is conveyed rightward in FIG. 2 by the toothed belt 6 driven by the motor 7 and moves to the home position.

Next, wiping and capping operations in the process of moving the ink carriage 2 will be described. FIG. 3 is a schematic diagram showing a state of wiping and capping by the print head maintenance mechanism M. In the figure, the elastic member 8 is the same as that of FIG. 1, but is drawn in a simplified shape in which the notch 22 is omitted. In addition, for convenience of understanding, the elastic member 8 is illustrated in a cross section.

FIG. 3A shows a state in which the ink cartridge 4 after printing has moved in the direction of the arrow toward the home position and has reached the position of the elastic member 8. When the ink cartridge 4 moves further rightward, the print head 4a of the ink cartridge 4 comes into contact with the first wiper portion 141 of the elastic member 8, and as shown in FIG. In response to a rightward pressing force from, the elastic member is elastically deformed so as to bend rightward near the base 21. At this time, since the elastic member 8 is formed of a material such as rubber, the concave portion 19 is also deformed so as to be slightly curved (in FIG. 3B, the curved portion is exaggerated). As the elastic member 8 is deformed, the first wiper portion 141 is also displaced rightward in the drawing.

When the ink cartridge 4 further moves rightward from this state, as shown in FIG. 3C, the elastic member 8 is elastically deformed from the vicinity of the base portion 21 until it is bent rightward substantially at right angles, and the concave portion 19 is formed. The print head 4a of the ink cartridge 4 is stored in the printer. At this time, the print head 4
a shows the first wiper portion 141, the projecting piece 20, and the side wall 1;
7 and 18 (see FIG. 1). In this way, the print head 4a of the ink cartridge 4 is stored in the recess 19, whereby the print head 4a is capped and the nozzles (not shown) of the print head 4a are prevented from drying. FIG. 3C shows a state in which the ink cartridge 4 is at the home position.

Next, when a print command is received, as shown in FIG. 3D, the ink cartridge 4 starts moving further rightward from the home position. With this movement, the print head 4a of the ink cartridge 4 tries to get over the first wiper section 141. Thereby, the elastic member 8 is elastically deformed so as to be bent further downward from the vicinity of the base 21.

When the ink cartridge 4 moves further rightward, as shown in FIG. 3 (e), the knife-edge-shaped tip portion 141a of the first wiper portion 141 is moved to the lower surface (ink ejection surface) of the print head 4a. The print head 4a is cleaned by sliding contact with the print head 4a.

Then, the ink cartridge 4 is further moved rightward, and the print head 4a is moved to the first wiper portion 14.
When the vehicle goes over 1, the elastic member 8 returns to its original state by its elastic restoring force, as shown in FIG.

Thereafter, the ink cartridge 4 reverses the direction and starts moving leftward. When the ink cartridge 4 moves to a certain position, the print head 4a of the cartridge 4 is moved to the elastic member 8 as shown in FIG.
Abuts on the second wiper portion 142.

When the ink cartridge 4 is still moved to the left, as shown in FIG.
42 is the print head 4a.
Wiping is performed in sliding contact with the lower surface of the print head 4a.
Is cleaned.

Then, the ink cartridge 4 moves further to the left, and the print head 4a
2, as shown in FIG.
Returns to its original state by its elastic restoring force. Thereafter, the ink cartridge 4 further moves leftward and is conveyed to the printing area, where a predetermined printing operation is performed.

According to the above-described embodiment, the wiper unit 14
And the cap part 15 are integrally formed by the elastic member 8, so that wiping and capping can be performed by one member. Further, since the wiping and capping are performed by the displacement of the wiper portion 14 and the cap portion 15 due to the elastic deformation of the elastic member 8, it is not necessary to provide a special cam mechanism or the like as in the related art.

In the embodiment described above, the leg 16 is formed on the elastic member 8, and the elastic member 8 is brought into contact with the wiper 14 by the
The elastic member 8 can be easily elastically deformed because it is bent at a substantially right angle near the base 21 of the cap 6 and the cap 15. As a result, wiping and capping operations can be performed smoothly, and even if there is a variation in the positional relationship between the elastic member 8 and the print head 4a due to the vertical elastic force of the elastic member 8, this is absorbed. Wiping and capping can be performed reliably.

Further, in the above-described embodiment, the wiper portion 14 is provided with the first wiper portion 141 and the second wiper portion 142 protruding in a direction opposite to the first wiper portion 141.
The first wiper portion 141 contacts the cartridge 4 when the ink cartridge 4 moves to the right, and the second wiper portion 142 contacts the cartridge 4 when the ink cartridge 4 moves to the left. Therefore, wiping can be performed twice at the start of printing in which the ink cartridge 4 moves out of the home position and moves to the printing area, and the cleaning effect of the print head 4a is doubled.

Further, in the above-described embodiment, since the cap portion 15 has the recess 19 for accommodating the print head 4a, the print head 4a is completely covered by the recess 19, and Drying can be effectively prevented.

Further, in the above-described embodiment, the tips 141a and 142a of the wipers 141 and 142 have a knife edge shape. And the wiping effect is improved.

FIG. 4 is a perspective view showing another embodiment of the print head maintenance mechanism according to the present invention. In the figure, reference numeral 23 denotes an elastic member formed of an elastomer or the like, similarly to the above-mentioned elastic member 8, and this elastic member 23 includes a pair of legs 231 and 232 extending substantially perpendicularly to the moving direction of the ink cartridge. Have these legs 231,
The box-shaped cap portion 24 is formed integrally with the 232. The cap portion 24 has a wall portion 24 around its periphery.
a, 24b, 24c, and 24d, and has a recess 25 that is open upward.

FIG. 5 is a schematic diagram for explaining the operation of the print head maintenance mechanism using the elastic member 23. As shown in FIG. 5A, the cap portion 24 of the elastic member 23
Is located slightly above the lower surface of the print head 4a of the ink cartridge 4 by a distance d.

When the ink cartridge 4 moves rightward in the drawing, the print head 4a is moved to the wall 2 of the cap 24.
4a. Thereafter, when the ink cartridge 4 further moves rightward, as shown in FIG. 5B, the print head 4a tries to get over the wall portion 24a while contacting the wall portion 24a.

At this time, the pair of leg portions 2 of the cap portion 24
31 and 232 are elastically deformed so as to be inclined rightward, whereby the upper surface position of the cap portion 24 is slightly lowered, and the print head 4a moves while sliding on the wall portion 24a. In this process, the print head 4a and the upper end surface of the wall portion 24a are in sliding contact with each other, and the print head 4a is wiped.
That is, the upper end surface of the wall portion 24a is a wiper portion that slides on the print head 4a and performs wiping. In order to enhance the wiping effect, it is of course possible to form the upper end surface of the wall portion 24a into a knife edge shape as in the previous embodiment.

When the ink cartridge 4 moves further to the right, the print head 4a fits into the recess 25 of the cap portion 24, as shown in FIG. At this time, the cap portion 24 is slightly displaced upward due to the elastic restoring force of the leg portions 231 and 232. Thus, the print head 4a is closed at the recess 25, and the capping is completed.
This position is the home position of the ink cartridge 4.

Although not shown in the drawings, when a print command is received thereafter, the print head 4a of the ink cartridge 4 comes out of the recess 25 of the cap portion 24, and the ink cartridge 4 is transported to the print area. In this process,
24 functions as a wiper that performs wiping by sliding contact with the print head 4a.

According to the embodiment shown in FIG. 4, the cap-type cap portion 24 covers the print head 4a for reliable capping, and the elastic member 23 can be formed in a simple shape, so that the manufacturing cost can be reduced. There is a merit that can be.

Each of the above-described embodiments is a preferred example for implementing the print head maintenance mechanism according to the present invention. However, the present invention is not limited to these embodiments, and various other embodiments are also possible. Can be adopted.

FIG. 6 shows an example in which a wiper 27, a cap 28 and a leg 29 are integrally formed on a plate-like elastic member 26. Tip portion 27a of wiper portion 27
Has a knife-edge shape to enhance the wiping effect. Further, a wall portion 30 surrounding the four sides is formed in the cap portion 28, and the tip portion of the print head is housed in the wall portion 30 to perform capping. Even with such a print head maintenance mechanism, wiping and capping are performed by displacing the wiper 27 and the cap 28 by elastically deforming the elastic member 26 so as to bend near the boundary between the cap 28 and the leg 29. be able to.

FIG. 7 shows another example, in which a recess 31 is formed in place of the wall 30 in FIG. 6, and the tip of the print head is accommodated in the recess 31. The other parts are the same as those in FIG. 6, and thus the same parts are denoted by the same reference numerals and detailed description thereof will be omitted.

In addition, as the material of the elastic member in the present invention, besides rubber, resin having high elasticity can be used. Further, the printer to which the above-described print head maintenance mechanism is applied is not limited to the structure shown in FIG. 2, and the present invention can be applied to various ink jet printers.

[0057]

According to the present invention, since the wiper portion and the cap portion are integrally formed by an elastic member, wiping and capping can be performed by one member, thereby reducing the number of parts and reducing the cost. it can. In addition, since the wiping and capping are performed by displacing the wiper portion and the cap portion by elastically deforming the elastic member, a cam mechanism or the like for driving the wiper portion and the cap portion as in the related art becomes unnecessary, There is an effect that the structure is simplified and the device can be miniaturized.

Further, the elastic member is formed with legs, and the elastic member is bent substantially at a right angle near the base of the leg and the cap by the contact of the ink cartridge, so that the elastic member can be easily formed. It can be elastically deformed, and the wiping and capping operations can be performed smoothly. Furthermore, even if there is a variation in the positional relationship between the elastic member and the print head, this can be absorbed by the elasticity of the elastic member, so that wiping and capping can be performed reliably.

Further, since the wiper portion is composed of the first wiper portion and the second wiper portion projecting in a direction opposite to the first wiper portion, wiping is performed twice at the start of printing. And the cleaning effect of the print head is doubled.

Further, by providing a recess for accommodating the print head in the cap portion, the print head is completely covered by the recess, and drying of the print head can be effectively prevented.

Further, by forming the tip of the wiper portion into a knife-edge shape, it is easy to remove deposits on the print head, and the wiping effect is further improved.

Further, by forming the leg portion and the box-shaped cap portion connected to the leg portion integrally with an elastic member, the print head can be reliably capped by the box-shaped cap portion. The manufacturing cost can be reduced by simplifying the shape of the elastic member.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a print head maintenance mechanism according to the present invention.

FIG. 2 is a perspective view of a main part of an ink jet printer using the print head maintenance mechanism of FIG.

FIG. 3 is a schematic diagram illustrating wiping and capping operations of a print head maintenance mechanism according to the present invention.

FIG. 4 is a perspective view showing another embodiment of the print head maintenance mechanism according to the present invention.

FIG. 5 is a schematic diagram illustrating the operation of the print head maintenance mechanism of FIG.

FIG. 6 is a perspective view showing another embodiment of the print head maintenance mechanism according to the present invention.

FIG. 7 is a perspective view showing another embodiment of the print head maintenance mechanism according to the present invention.

FIG. 8 is a perspective view of a main part of an ink jet printer having a conventional print head maintenance mechanism.

FIG. 9 is a perspective view of a wiper in a conventional print head maintenance mechanism.

FIG. 10 is a perspective view of a cap portion in a conventional print head maintenance mechanism.

FIG. 11 is a schematic diagram illustrating wiping and capping operations in a conventional print head maintenance mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet printer 2 Ink carriage 3 Printing paper 4 Ink cartridge 4a Print head 8 Elastic member 14 Wiper part 15 Cap part 16 Leg part 23 Elastic member 24 Cap part 26 Elastic member 27 Wiper part 28 Cap part 29 Leg M Print head maintenance mechanism

Claims (6)

[Claims] A print head maintenance mechanism provided in an ink jet type recording apparatus for performing printing by ejecting ink in an ink cartridge from a print head onto a recording medium, and performing wiping and capping of the print head; The wiper unit for performing the wiping and the cap unit for performing the capping are integrally formed by an elastic member, and the wiper unit is configured to abut the elastic member when the ink cartridge moves to deform the member elastically. A print head maintenance mechanism wherein a cap portion is displaced, the wiper portion cleans the print head, and the cap portion covers the print head. 2. The elastic member has a leg extending substantially perpendicular to the direction of movement of the ink cartridge. The wiper is formed on the opposite side of the leg, and the leg and the wiper are formed. And the elastic member is bent substantially at a right angle near the base between the leg and the cap by bringing the ink cartridge into contact with the wiper. The printhead maintenance mechanism according to claim 1. 3. The wiper portion comprises a first wiper portion protruding laterally with respect to the leg portion, and a second wiper portion protruding in a direction opposite to the first wiper portion. 3. The print head according to claim 2, wherein the ink cartridge comes into contact with the first wiper portion when moving in the first direction, and comes into contact with the second wiper portion when moving in the second direction. Maintenance mechanism. 4. The print head maintenance mechanism according to claim 2, wherein said cap portion has a recess for accommodating said print head. 5. The print head maintenance mechanism according to claim 2, wherein a tip portion of said wiper portion has a knife edge shape. 6. The elastic member has a leg portion extending substantially perpendicular to the direction of movement of the ink cartridge, and a box-shaped cap portion is formed integrally with the leg portion, The cap portion is surrounded by a wall portion and is open upward, and an upper end surface of the wall portion is formed as a wiper portion that slides on the print head, and causes the ink cartridge to contact the cap portion. 2. The printhead maintenance mechanism according to claim 1, wherein the leg portion is elastically deformed.