Search

EP-4299329-B1 - PRINTING APPARATUS

EP4299329B1EP 4299329 B1EP4299329 B1EP 4299329B1EP-4299329-B1

Inventors

  • KOJIMA, TAKAHIRO

Dates

Publication Date
20260506
Application Date
20230623

Claims (12)

  1. A printing apparatus (101) comprising: a feeding portion (102) configured to feed a printing material from a continuous sheet with a roll shape; a printing head (114) configured to perform printing on the printing material at a downstream side of the feeding portion; a winding portion (111) configured to wind a part of the printing material at a downstream side of the printing head; a conveying portion (502) configured to convey the printing material while performing printing on the printing material with the printing head, at a position where the conveying portion is opposed to the printing head; a movement mechanism configured to move at least one of the printing head and the conveying portion and change an opposing interval between the printing head and the conveying portion; a control portion (112) configured to control the feeding portion and the winding portion in such a manner that a predetermined tension is applied to the printing material; characterized in that the printing apparatus further comprises a detecting portion (103) configured to detect floating of the printing material, wherein the movement mechanism performs a separation operation to widen the opposing interval in a case where the detecting portion detects the floating while the predetermined tension is applied to the printing material.
  2. The printing apparatus according to claim 1, further comprising a tension detecting portion configured to detect tension of the printing material that is being conveyed, wherein the detecting portion is disposed on an upstream side of the printing head on a conveyance path of the printing material, and wherein the tension detecting portion is disposed between the detecting portion and the printing head on the conveyance path.
  3. The printing apparatus according to claim 1, wherein the control portion performs a conveyance stop operation together with the separation operation in a case where the detecting portion detects the floating, the conveyance stop operation being an operation to stop feeding of the printing material by the feeding portion and stop winding of the printing material by the winding portion.
  4. The printing apparatus according to claim 3, wherein, in a case where the detecting portion detects the floating, the control portion performs the separation operation and then performs the conveyance stop operation.
  5. The printing apparatus according to claim 4, wherein, in the conveyance stop operation, the control portion stops the feeding and then stops the winding.
  6. The printing apparatus according to claim 3, wherein the control portion performs the separation operation and, simultaneously therewith, stops the feeding in the conveyance stop operation, and then stops the winding in the conveyance stop operation.
  7. The printing apparatus according to any one of claims 1 to 6, wherein the separation operation is an operation to move the conveying portion in a direction away from the printing head.
  8. The printing apparatus according to any one of claims 1 to 6, wherein the separation operation is an operation to move the printing head in a direction away from the conveying portion.
  9. The printing apparatus according to any one of claims 1 to 6, wherein the separation operation is an operation to move the conveying portion in a direction away from the printing head and move the printing head in a direction away from the conveying portion.
  10. The printing apparatus according to claim 1, further comprising a meander correcting portion configured to correct a meander of the printing material, the meander correcting portion being disposed between the feeding portion and the printing head on a conveyance path of the printing material, wherein the detecting portion is disposed between the meander correcting portion and the printing head on the conveyance path.
  11. The printing apparatus according to any one of claims 1 to 10, wherein the detecting portion includes: a light emitting portion configured to emit detection light above the printing material and along a conveyance path of the printing material; and a light receiving portion configured to receive the detection light, and the detecting portion detects the floating by change in amount of light received by the light receiving portion.
  12. The printing apparatus according to any one of claims 1 to 10, wherein the conveying portion includes: a supporting member configured to support the printing material at a position opposed to the printing head; and a conveyance roller that is rotatably disposed at a position adjacent to the supporting member along a conveyance path of the printing material.

Description

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an emergency evacuation method performed when floating of a printing material that is being conveyed is detected in a printing apparatus. Description of the Related Art Conventionally, with regard to a printing apparatus that conveys and performs printing on a long printing material such as a roll sheet while applying tension, sometimes a phenomenon occurs, in which the printing material floats, due to abnormalities such as faulty conveying or faulty holding, and the printing material bumps into a printing head, hence this may result in failure of the printing head. Japanese Patent Application Publication No. 2010-111474 discloses a configuration in which a guide member for regulating floating of a printing material and units for detecting the floating of the printing material are disposed on an upstream side of a printing head, and in which a convey unit is stopped when the floating of the printing material has been detected. US 8,827,398 B2 relates to an image recording device wherein a print head is positioned at a retracted position when a tension of a print medium is being altered by a tension adjustment unit. US 2019/299684 A1 relates to a liquid jetting apparatus for coping with the floating of a sheet-like medium. SUMMARY OF THE INVENTION However, when the conveying unit is stopped due to the detection of the floating of the printing material while conveying a web of the printing material under tension control, tension applied on the printing material below the printing head may not be maintained. In this case, there is a concern that the printing material passing immediately below the printing head may float due to vibration caused by stopping the conveyance, and the printing material may bump into the printing head, hence this may result in failure of the printing head. The present invention provides a technology that makes it possible to avoid contact between the printing material and the printing head. The present invention in its one aspect provides a printing apparatus as specified in claims 1 to 12. According to the present invention, it is possible to avoid contact between the printing material and the printing head. Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a configuration of a printing apparatus during printing according to a first embodiment;FIG. 2 is a schematic cross-sectional view of a configuration of the printing apparatus during separation according to the first embodiment;FIG. 3 is a schematic cross-sectional view of a configuration of the printing apparatus during cleaning according to the first embodiment;FIG. 4 is a block diagram of a control configuration of the printing apparatus according to the first embodiment;FIGS. 5A and 5B are explanatory diagrams of a floating detection sensor according to the first embodiment;FIG. 6 is a configuration diagram of a printing portion conveying portion according to the first embodiment;FIG. 7 is a configuration diagram of the printing portion conveying portion according to the first embodiment;FIGS. 8A to 8C are explanatory diagrams of a control configuration of the printing portion conveying portion according to the first embodiment;FIG. 9 is an explanatory diagram of a configuration of a lifting/lowering member according to the first embodiment;FIG. 10 is an explanatory diagram of another configuration example of a printing head lifting/lowering mechanism according to the first embodiment;FIGS. 11A to 11D are explanatory diagrams of the other configuration example of the printing head lifting/lowering mechanism according to the first embodiment.;FIG. 12 is a block diagram of a separation control configuration according to the first embodiment;FIG. 13 is a flowchart of separation control according to the first embodiment; andFIG. 14 is a flowchart of separation control according to a second embodiment. DESCRIPTION OF THE EMBODIMENTS Hereinafter, embodiments of the present invention will be illustratively described in detail on the basis of examples with reference to the drawings. Note that, dimensions, materials, shapes, relative positional relationships, and the like of structural elements described herein should be appropriately changed depending on various conditions and structures of apparatuses to which the present invention is applied. In addition, not all of the combinations of features that are described according to the following embodiments are necessarily required with respect to means to solve problems according to the present invention. The structural elements described according to the embodiments are merely illustrative, and are not intended to limit the scope of the present invention only to them. First Embodiment First, it is defined that a shee