The present disclosure relates to a printing apparatus that prints an image on a printing medium by a printing head mounted on a carriage movable along the printing medium, and specifically relates to a printing apparatus that can switch a distance between the printing head and the printing medium.
An ink jet printing apparatus has been known as an image formation apparatus such as a printer, a facsimile, and a copier. The ink jet printing apparatus includes a recovery unit that maintains and recovers the ink ejection reliability for forming an image by ejecting ink from a printing head. Additionally, the ink jet printing apparatus includes a guide rail and a slidable sliding member for scanning a carriage on which the printing head is mounted. Moreover, the ink jet printing apparatus includes a switching mechanism that switches a distance between a printing medium and the printing head (so-called a head-to-paper gap) depending on the type of the printing medium.
Japanese Patent Laid-Open No. 2009-61768 discloses a configuration in which a printing apparatus having a configuration of switching a head-to-paper gap between a printing head and a printing medium performs a recovery operation for the printing head with an easy and inexpensive configuration. Specifically, a regulation unit that regulates the movement of a carriage in a vertically upward direction is provided to the carriage. The regulation unit is arranged on a back side of a guide rail and regulates the movement of the carriage with the regulation unit being brought into contact with a back surface of the guide rail once the carriage moves in the vertically upward direction.
However, in a case where the printing apparatus has the configuration of switching the head-to-paper gap between the printing head and the printing medium, a clearance between the regulation unit and the guide rail is changed by changing the head-to-paper gap. In a case where a gap between the regulation unit and the back surface of the guide rail is large, and a cap pressure is greater than the weight of the carriage, the carriage is uplifted at the time of the recovery operation, and it is impossible to execute the sufficient recovery operation.
Additionally, there is a risk that the carriage is dropped off from the guide rail in a case where a user raises the carriage to handle jam recovery that occurs during printing or a case where the printing apparatus drops by mistake during distribution, for example.
Therefore, in the light of the above-described problems, an object of the present disclosure is to provide a printing apparatus having a structure that can suppress the carriage uplift and the carriage drop-off.
An embodiment of the present invention is a printing apparatus including: a printing head that includes a nozzle ejecting ink for printing on a printing medium conveyed in a conveyance direction; a carriage on which the printing head is mounted and that reciprocally moves in a main scanning direction; a sliding member attached to the carriage such that the carriage can change a position in a vertical direction; and a guide member that includes a first surface with which the sliding member is brought into contact and a second surface as a back surface of the first surface and guides the movement of the main scanning direction of the carriage, in which the sliding member includes a first regulation unit facing the second surface in a position away from the second surface at a predetermined distance.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Embodiments are described in detail below with reference to the appended drawings. Note that, the following embodiments are not intended to limit the invention according to the scope of claims. Additionally, although there are described multiple characteristics in the following embodiments, not all the multiple characteristics are necessarily essential to solve the problems, and the multiple characteristics may be used in combination as needed. Moreover, in the appended drawings, the same or similar configurations may be given with the same reference numerals, and duplicated descriptions may be omitted herein.
In the present specification, “printing” indicates a case of forming meaningful information such as characters and graphics. However, it is not limited to this case, and “printing” also indicates a case of widely forming an image, a design, a pattern, and the like on a printing medium or processing the medium regardless of it is meaningful or meaningless and regardless of whether it is visible for a human to perceive with vision.
Additionally, the “printing medium” includes not only printing paper in the form of sheet used in a common image formation apparatus but also roll paper. Also, the “printing medium” includes an arbitrary medium that can be conveyed by a conveyance device included in the printing apparatus such as cloth, a plastic film (OHP), a metallic plate, glass, ceramics, wood, and leather.
Moreover, “ink” can be construed widely as with the definition of “printing” described above. In the present specification, the ink represents a liquid that is applied onto the printing medium and used for formation of an image, a design, a pattern, and the like, processing of the printing medium, or processing of the ink (for example, solidification or insolubilization of color material in the ink applied to the printing medium).
Furthermore, a distance between a platen supporting the printing medium and the printing head is referred to as a “head-to-paper distance”. A distance between the regulation unit and a back surface of a sliding surface of a guide member is referred to as a “clearance distance”.
Additionally, a position of the carriage unit in a vertical direction at the time of performing printing on the printing medium of plain paper is referred to as a “normal position”. The head-to-paper distance in a case of the normal position is referred to as a “normal head-to-paper distance”. Moreover, a position of the carriage unit in the vertical direction in which the printing head is away from the printing medium at the time of performing printing on the printing medium of thick paper such as an envelope is referred to as a “thick paper position”. Furthermore, a position of the carriage unit in the vertical direction in which the printing head is brought close to the printing medium at the time of performing printing on the printing medium of special paper is referred to as a “special paper position”. Note that, the three types of positions as described above are used as an example in the following description; however, the number of types of the positions is not limited to three as long as there are multiple types.
<Configuration of Ink Jet Printing Apparatus>
First, a configuration of an ink jet printing apparatus according to the present embodiment is described with reference to
The printing apparatus 1 includes a conveyance unit 40 that feeds the printing medium 2 in the form of sheet, and the conveyance unit 40 conveys the printing medium 2 in a +Y direction orthogonal to the main scanning direction of the carriage 500 on which the printing head 3 is mounted. Note that, the +Y direction in which the printing medium 2 is conveyed is referred to as a “conveyance direction”. Additionally, a platen 42 is provided below a range in which the printing head 3 moves so as to face the printing head 3. An image is printed with the carriage 500 moving in the main scanning direction and the printing head 3 being driven in synchronization with the movement. Thereafter, a predetermined amount of paper feeding is performed by a conveyance roller 41. The image printing on the entire printing medium 2 is performed by alternately repeating the reciprocal movement of the carriage 500 and the paper feeding as described above.
Additionally, the printing apparatus 1 is provided with a recovery unit 30 that prevents clogging of the nozzle in the printing head 3 and also maintains and recovers the printing characteristic of the nozzle, specifically, the ejection performance of the ink. The printing apparatus 1 performs the recovery operation by pressing the printing head 3 by a cap unit 31 (see
<Configuration of Carriage Unit>
Next, a configuration of a carriage unit is described with reference to
In contrast,
The carriage 500 includes an upper slider 501 (a third sliding member) and front sliders 502 (second sliding members) (each in different positions in the X direction, two in total). The upper slider 501 (the third sliding member) is brought into contact with a sliding surface 511 (a fifth surface) of a main frame 510. The front sliders 502 (the second sliding members) are brought into contact with a sliding surface 512 (a third surface) of the main frame 510. With the configuration as described above, the position of the printing head 3 with respect to the conveyance direction of the printing medium 2 is determined. A sliding surface of the upper slider 501 (the third sliding member) is 501a, and sliding surfaces of the front sliders 502 (the second sliding members) are 502a. Note that, the upper slider 501 (the third sliding member) and the front sliders 502 (the second sliding members) may not be integral with the carriage 500 and may be separated members attached to the carriage 500.
Additionally, the carriage 500 includes the sliding member 530 and the switching member 540. As illustrated in
A switching lever 7 that can advance and retract in the Y direction enters a switching contact portion 548 formed on the switching member 540 and moves the carriage 500 in the X direction; with this, the switching member 540 is slid proportionally to the carriage 500. Thus, it is possible to change the head-to-paper distance.
Because the head-to-paper distance greatly affects the image quality in the printing apparatus 1, the guide rail 520 is formed to be proportionally movable with respect to the main frame 510 in the vertical direction and is formed to be able to adjust the head-to-paper distance.
<Configuration Related to Switching of Head-to-Paper Distance>
Next, configurations of the sliding member 530 and the switching member 540 for switching the head-to-paper distance are described with reference to
The printing medium 2 as a printing target has various types, and the thickness thereof is various as well. For this reason, the printing apparatus 1 of the present embodiment includes the switching member 540 between the carriage 500 and the sliding member 530 to appropriately change the distance between the printing medium 2 and the printing head 3. A reception surface 505 of the carriage 500 is put in contact with a CR supporter 544 of the switching member 540, and the CR supporter 544 supports the carriage 500 at two points. Additionally, a contact portion of the switching member 540 that is put in contact with a switching supporter 534 of the sliding member 530 has a stepwise shape 541 including three flat surface portions that are a high level portion 541a, a middle level portion 541b, and a low level portion 541c. Away in the X direction, there is one more pair of the switching supporter 534 and the three flat surface portions.
The sliding member 530 is mounted proportionally to the carriage so as to be displaceable in the vertical direction and is held by front holders 507 holding a front side that are formed at two ends of the carriage in the X direction and a rear holder 508 holding a rear side.
The position of the switching supporter 534 in the Y direction and the position of the CR supporter 544 in the Y direction are the same so as to suppress rotation of the switching member 540 about an X axis.
In a case where the printing medium 2 is plain paper, the printing operation on the printing medium 2 of plain paper and the recovery operation for the printing head 3 are performed while the carriage 500 is in the normal position in which the switching supporter 534 is put in contact with the middle level portion 541b. On the other hand, in a case of performing printing on photo paper that requires a high image quality (in a case where the printing medium 2 is photo paper), the head-to-paper distance needs to be short to suppress deviated landing of an ink droplet. Accordingly, in this case, the printing operation on the printing medium 2 and the recovery operation for the printing head 3 are performed while the switching supporter 534 is put in contact with the low level portion 541c, in other words, while the carriage 500 is in the special paper position. Additionally, in a case where printing is performed on thick paper or a medium of a material curled easily (in a case where the printing medium 2 is thick paper or the like), the head-to-paper distance needs to be long to prevent rubbing between the printing medium 2 and the printing head 3. Accordingly, in this case, the printing operation on the printing medium 2 and the recovery operation for the printing head 3 are performed while the switching supporter 534 is put in contact with the high level portion 541a, in other words, while the carriage 500 is in the thick paper position.
It is possible to displace the carriage 500 in the vertical direction by sliding and moving the switching member 540 proportionally to the carriage 500 in the main scanning direction as illustrated in
Additionally, as illustrated in
A portion of the switching member 540 that includes the stepwise shape 542 and the regulation surface 543 is referred to as a “pinched portion 545”. As illustrated in
As illustrated in
Once the sliding member 530 is raised, a first regulation unit 533 is brought into contact with a surface 522 (a second surface) that is a back surface of the sliding surface 521 (the first surface) of the guide rail 520. The pinched portion 545 is pinched between the fifth regulation unit 503 and the fourth regulation unit 532 so as to hold the switching member 540, and thus it is possible to suppress the positional displacement of the switching member 540 with respect to the carriage 500. Once the capping is released, the original contact state and the state with a clearance are obtained again because of the gravity.
The clearance distance of the upper clearance 545a is constant even if the head-to-paper distance is changed, and the clearance distance of the lower clearance 545b is also constant even if the head-to-paper distance is changed. In all the head-to-paper distances, the stepwise shape 542 is regulated by the fourth regulation unit 532, and the fifth regulation unit 503 is regulated by the regulation surface 543; thus, a relationship in which the pinched portion 545 is pinched from top and bottom is obtained. With the relationship as described above, a configuration in which the sliding member 530 and the switching member 540 are not dropped off from the carriage 500 is obtained.
<Assembling Steps>
Next, assembling steps of the carriage unit are described with reference to
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
<Configuration of Regulation Unit>
As described above, it is required to suppress the drop-off of the carriage 500 from the main frame 510 and the guide rail 520 in order to appropriately execute the recovery operation in all the head-to-paper distances or to prepare for a case where a drop impact at the time of distribution is applied.
However, in a case where the regulation unit is provided to a part that changes in the vertical direction with respect to the guide rail 520 along with the change in the head-to-paper distance, the clearance between the regulation unit and the guide rail is changed with the change in the head-to-paper distance. In this case, the clearance between the regulation unit and the guide rail 520 is wider as the head-to-paper distance is shorter, and there is a risk that it is impossible to suppress the drop-off of the carriage.
To deal with this, in the present embodiment, as illustrated in
As illustrated in
At the time of capping, as illustrated in
Additionally, as illustrated in
According to the present embodiment described above, it is possible to provide a printing apparatus having a structure that can suppress the carriage uplift and the carriage drop-off.
In the above-described first embodiment, the printing apparatus 1 employing the configuration in which the sliding surface 521 (the first surface) and the surface 522 (the second surface) of the guide rail 520 are tilted with respect to a horizontal plane is described as an example. However, as illustrated in
According to the present embodiment described above, it is possible to provide a printing apparatus in which the uplift amount of the carriage is reduced more than the first embodiment.
As illustrated in
According to the present embodiment, it is possible to achieve a reduction in the size and the number of parts of the printing apparatus.
The present embodiment is described with reference to
The following reference numerals and dimensions are used in the above-described drawings.
In addition to the above, a region between the boundary 507a and the boundary 508a is indicated by a dimension a. Hereinafter, the force P1 is obtained with reference to
The equations of equilibrium of the carriage 500 can be represented as P1=R1 in the Y direction and W=N in the Z direction.
The equation of equilibrium of the moment of the carriage 500 can be represented as R1×d+P1×f+Q×e=N×b+W×k+Q×h, where a point A is the center.
The equation of equilibrium of the force of the sliding member 530 is omitted since it is an obvious equation of the reaction.
The equation of equilibrium of the force couple of the sliding member 530 can be represented as Q×(h−e)=N×(i−b).
According to the above, the solution for the force P1 can be represented by using the following Equation (1):
P1=W×(i+k)/(d+f) Equation (1).
Next, the force P2 is obtained with reference to
The equations of equilibrium of the force of the carriage 500 can be represented as P2=R2 in the Y direction and W+L=F in the Z direction.
The equation of equilibrium of the moment of the carriage 500 can be represented as R2×d+P2×f+Q×e+F×j+L×m=W×k+Q×h, where the point A is the center.
The equation of equilibrium of the force of the sliding member 530 is omitted since it is an obvious equation of the reaction.
The equation of equilibrium of the force couple of the sliding member 530 can be represented as Q×(e−h)=L×(c−m).
According to the above, the solution for the force P2 can be represented by using the following Equation (2):
P2={−(F−W)×c+W×k−F xj}/(d+f) Equation (2).
At last, the force P3 is obtained with reference to
The equations of equilibrium of the force of the carriage 500 can be represented as P3=R3 in the Y direction and W+L=F in the Z direction.
The equation of equilibrium of the moment of the carriage 500 can be represented as −R3×d−P3×f+Q×e+F×j+L×m=W×k+Q×h, where the point A is the center.
The equation of equilibrium of the force of the sliding member 530 is omitted since it is an obvious equation of the reaction.
The equation of equilibrium of the force couple of the sliding member 530 can be represented as Q×(e−h)=L×(c−m).
According to the above, the solution for the force P3 can be represented by using the following Equation (3):
P3={(F−W)×c−W×k+F×j}/(d+f) Equation (3).
The force P1 needs to be equal to or greater than a predetermined magnitude for the front slider 502 (the second sliding member) to move along the main frame 510 against the oscillation disturbance acting during scanning of the carriage 500 and the tilt of the whole printing apparatus. Additionally, the force P2 is preferably immovable against the load in the Y direction received by the printing head 3 from the cap unit 31 at the time of capping and the tilt of the whole printing apparatus, and the force P2 needs to be equal to or greater than a predetermined magnitude. The force P3 is preferably immovable against the load in the Y direction received by the printing head 3 from the cap unit 31 at the time of capping and the tilt of the whole printing apparatus, and the force P3 needs to be equal to or greater than a predetermined magnitude.
It can be seen that the dimension b that is the distance in the Y direction from the boundary 507a to the CR supporter 544 and the dimension m that is the distance in the Y direction from the boundary 507a to the pinched portion 545 do not affect the force P1, P2, and P3. The above dimensions may be appropriately arranged within a dimension a of the holder of the carriage 500.
Here are focused the dimension i that is the distance in the Y direction from the boundary 507a to the sliding surface 531 and the dimension c that is the distance in the Y direction from the boundary 507a to the first regulation unit 533. According to Equation (1), as the dimension i is greater, the force P1 can be greater. According to Equation (2), as the dimension c is smaller, the force P2 can be greater. According to Equation (3), as the dimension c is greater, the force P3 can be greater. A difference between Equation (2) and Equation (3) is based on a difference between the places with which the regulation unit is brought into contact. In a case where the gravity W of the carriage unit is positioned in the +Y direction in the conveyance direction of the cap pressure F, the front slider 502 (the second sliding member), the upper slider 501 (the third sliding member), and the first regulation unit 533 are brought into contact at the time of capping. In this case, the first regulation unit 533 is put close to the front holder 507 side (
At last, the idea of the present disclosure is implemented by appropriately combining the contents of the above-described embodiments.
Embodiment(s) of the present disclosure can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.
According to the present disclosure, it is possible to provide a printing apparatus having a structure that can suppress the carriage uplift and the carriage drop-off.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2022-064171, filed Apr. 7, 2022, which is hereby incorporated by reference wherein in its entirety.
Number | Date | Country | Kind |
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2022-064171 | Apr 2022 | JP | national |