JP2018008460A - Platen device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a platen device which includes a grid roller disposed between an upstream end of a flat bed, in a direction of conveyance, and a downstream end of a rear apron, in the direction of conveyance, and which has a simple structure, but facilitates the mounting of the rear apron.SOLUTION: The platen device comprises: a bed where a medium is to be disposed; a rear apron for guiding the medium to the bed; and a grid roller which is disposed between an upstream end of the bed, in a direction of conveyance of the medium, and a downstream end of the rear apron, in the direction of conveyance of the medium, and which conveys the medium in the direction of conveyance. The platen device also comprises support members for rotatably supporting the grid roller, the support members each having a rear apron supporting portion provided at an upstream end of the support member, in the direction of conveyance. The rear apron includes fitting portions to be engaged with the rear apron supporting portions. Engagement of the fitting portions of the rear apron with the support members causes the support members to support the rear apron.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a platen device, and more particularly to a platen device used for transporting media in an ink jet printer, a cutting plotter, or the like.

  In this specification, “media” includes not only various recording media made of paper such as plain paper but also those made of various materials such as resin materials such as PVC and polyester. And

  In general, a platen device used for transporting media in an inkjet printer, a cutting plotter, or the like has a surface disposed on the lower side of the inkjet head or the cutting head so as to face the inkjet head of the inkjet printer or the cutting head of the cutting plotter. A flat flat bed and a rear apron that is connected to the flat bed on the transport start side in the transport direction when transporting the media to the flat bed and guides the media onto the flat bed.

  In this specification, the “conveying direction” when conveying a medium is appropriately referred to as a “sub-scanning direction”, and the “direction orthogonal to the conveying direction”, that is, the “direction orthogonal to the sub-scanning direction” is referred to. This is appropriately referred to as “main scanning direction”.

  Further, in this specification, the starting side of the conveyance in the conveyance direction is appropriately referred to as “upstream in the conveyance direction” or “upstream in the sub-scanning direction”, while the end point of conveyance in the conveyance direction is referred to as “downstream in the conveyance direction”. Or “downstream in the sub-scanning direction” as appropriate.

  In such a platen device, a conveyance mechanism constituted by a grid roller and a pinch roller which are driving rollers is positioned at a substantially central position in the sub-scanning direction in a flat plate which extends in the main scanning direction and the sub-scanning direction. A plurality of lines are arranged linearly at appropriate intervals along the main scanning direction.

  The grid roller that constitutes the transport mechanism includes a cylindrical roller shaft, a roller member that is externally fitted in a state protruding from the roller shaft in a radial method, and a friction member that is provided on the outer peripheral surface of the roller member. On the lower side of the flat bed, the upper part of the grid roller (roller member) is arranged to protrude upward from the hole formed in the flat bed. The grid roller is configured to rotate by driving a motor.

  On the other hand, the pinch roller is disposed above the grid roller and is always urged in a direction in contact with the grid roller.

  Accordingly, the media sandwiched between the grid roller and the pinch roller is transported in the transport direction by rotating the grid roller.

  The rear apron for guiding the media to the flat bed has substantially the same length as the flat bed in the main scanning direction and an appropriate length in the sub scanning direction. Further, the rear apron has a shape that gradually curves downward from the downstream side in the sub-scanning direction toward the upstream side in the sub-scanning direction in the sub-scanning direction.

  Conventionally, in the platen device as described above, for example, as shown in Japanese Utility Model Publication No. 6-5919, the end portion of the rear apron on the downstream side in the sub-scanning direction is connected to the end portion on the upstream side in the sub-scanning direction of the flat bed. By connecting, the rear apron that guides the media to the flat bed was installed.

  By the way, in the above-described conventional platen device, a hole is formed in a portion corresponding to the roller member in the flat bed, a grid roller is disposed below the hole, and a part of the grid roller is formed from the hole. The grid roller and the pinch roller were brought into contact with each other by protruding the upper side of the.

  However, for the purpose of reducing the cost of the grit roller, a method of providing a friction member on the peripheral surface of the roller shaft without using a roller member has been proposed.

  In other words, by providing a friction member on the outer peripheral surface of a cylindrical roller shaft formed in a single shaft shape along the main scanning direction, the grid bed can be connected to the flat bed in a state where the grid roller does not protrude from the roller shaft in the radial method. There has been proposed a method of arranging along an end portion on the upstream side in the scanning direction.

However, in this method, the grid roller is arranged in a state that does not protrude from the roller shaft to the diameter method, so the flat bed is shortened in the sub-scanning direction, and the grid roller is exposed to the outside, so that the grid roller and the pinch roller are not exposed. It was necessary to make contact.
In this case, since the flat bed is shortened in the flat bed sub-scanning direction, the end of the rear apron on the downstream side in the sub-scanning direction can be easily coupled to the end of the flat bed in the sub-scanning direction on the upstream side. There was a problem that it was difficult to attach the rear apron that guides the media to the flat bed.

No. 6-5919

  The present invention has been made in view of the various problems and demands of the conventional technology as described above, and its object is to convey the upstream end of the bed in the conveyance direction and the conveyance direction of the rear apron. An object of the present invention is to provide a platen device in which a rear apron can be easily attached with a simple configuration in a platen device in which a grid roller is arranged between the downstream end portion.

  In order to achieve the above object, the present invention provides a bed on which a medium is arranged, a rear apron for guiding the medium to the bed, an end of the bed on the upstream side in the transport direction of the medium, and the rear apron. A platen device provided with a grid roller disposed between the downstream end of the medium in the transport direction and transporting the medium in the transport direction, including a support member that rotatably supports the grid roller, The support member includes a rear apron support portion provided at an end portion on the upstream side in the transport direction of the support member, the rear apron includes an insertion portion that engages with the rear apron support portion, and the insertion of the rear apron. The part is engaged with the support member, and the support member supports the rear apron.

  Therefore, according to the above-described present invention, the rear apron can be easily supported by the support member by engaging the insertion portion with the rear apron support portion, and the medium is placed in the gap between the grid roller and the rear apron by the closing portion. Depressing can be prevented.

  Further, according to the present invention, in the above-described present invention, the rear apron includes a closing portion that is arranged in parallel with the insertion portion and is disposed in the vicinity of the peripheral surface of the grid roller, and the rear apron of the support member. An apron support portion is sandwiched between the closing portion and the insertion portion of the rear apron.

  Therefore, according to the present invention described above, the rear apron support portion is held between the closing portion and the insertion portion, so that the rear apron can be reliably supported by the support member.

  Further, the present invention is the above-described present invention, wherein the support member includes a bed support portion that supports an end of the bed on the upstream side in the transport direction on the downstream side in the transport direction, and the upstream of the bed in the transport direction. The end on the side is supported by the bed support part of the support member.

  Therefore, according to the present invention described above, by appropriately setting the height dimension of the rear apron support portion and the bed support portion in the support member, the positional relationship in the high direction between the bed and the rear apron is appropriately set. Can be adjusted.

  In the present invention described above, the present invention further includes a vertical wall erected on the lower side of the rear apron and a shielding member disposed on an upper end of the vertical wall. When the rear apron engages with the support member, the shielding member is urged by the lower surface of the rear apron.

  Therefore, according to this invention mentioned above, it becomes possible to interrupt | block the air flow in the lower surface of a rear apron by adjusting the dimension of the height direction of a vertical wall and a shielding member.

  In the present invention described above, the shielding member is made of an elastically deformable material.

  According to the present invention, in a platen device in which a grid roller is arranged between an end portion on the upstream side in the transport direction of the bed and an end portion on the downstream side in the transport direction of the rear apron, the rear apron is easily attached with a simple configuration. Will be able to.

FIG. 1 is a perspective view illustrating a configuration of a platen device according to an embodiment of the present invention. FIG. 2 is a partially enlarged view of the platen device shown in FIG. FIG. 3 is an explanatory diagram schematically showing an end surface configuration along line AA in FIG. 1. FIG. 4 is an enlarged explanatory view of the main part of FIG. FIG. 5 is an explanatory perspective view of the frame member. 6 (a), 6 (b), and 6 (c) are schematic perspective views of the main part of the platen device with the flat bed, the rear apron, and the front apron removed. FIG. 7A is an explanatory perspective view of the end support member of the support member, and FIG. 7B is an illustration showing a state in which the flat bed and the rear apron are attached to the end support member. FIG. FIGS. 8A and 8B are explanatory views showing a state in which the flat bed and the rear apron are attached to the end support member. FIG. 9A is an explanatory perspective view of the intermediate support member of the support members, and FIG. 9B is an explanatory view showing a state in which the flat bed and the rear apron are attached to the intermediate support member. FIG.

  Hereinafter, an example of an embodiment of a platen device according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an explanatory perspective view showing an example of an embodiment of a platen device according to the present invention, and FIG. 2 is a partially enlarged view of the platen device shown in FIG. 3 is an explanatory view schematically showing an end face configuration taken along line AA of FIG. 1, and FIG. 4 is an enlarged explanatory view of a main part of FIG. The main scanning direction in FIGS. 3 and 4 is a direction extending in the vertical direction from the paper surface.

  As shown in FIGS. 1 to 3, the platen device 10 includes a flat bed 14 disposed on a fixed frame member 12 below the ink jet head and the cutting head, and an upstream end of the flat bed 14 in the sub-scanning direction. A support member 16 disposed on the frame member 12 in the vicinity of the portion 14a, a single axial grid roller 18 rotatably supported by the support member 16 and extending in the main scanning direction, and the support member 16 The rear apron 20 disposed upstream in the sub-scanning direction and the front apron 24 coupled to the downstream end 14b in the sub-scanning direction of the flat bed 14 are configured.

  In addition, a flat bed should just be a surface with a flat surface, ie, a horizontal surface, and a back surface may not be a horizontal surface. However, the flat bed 14 in the present embodiment has a horizontal surface not only on the front surface but also on the back surface.

  Further, as shown in FIG. 3, the platen device 10 is erected on the upstream side of the flat bed 14 in the sub scanning direction of the frame member 12, more specifically, on the lower side of the rear apron 20 and on the upper side of the frame member 12. A shielding member 28 formed of an elastically deformable material such as sponge is attached to the upper end of the vertical wall 26.

  The vertical wall 26 and the shielding member 28 are elastically deformed by the shielding member 28 being urged by the lower surface 20a of the rear apron 20 when the rear apron 20 is attached to the support member 16 by a method described later. The size is set so that the lower surface 20a of the first member and the shielding member 28 are in pressure contact with each other.

  As shown in FIGS. 1 and 2, the grid roller 18 has a length that substantially matches the entire length of the platen device 10 in the main scanning direction. Reference numeral 18a denotes a friction member (rubber) disposed on the outer peripheral surface of the roller shaft in order to improve the frictional resistance when the medium is transported, and is provided at a plurality of positions at intervals. Reference numeral 18b denotes a drive shaft connected to a motor (not shown) that is a drive source, and the grid roller 18 is rotated by rotating the drive shaft 18b by the motor.

  FIG. 5 shows a perspective view of the frame member 12. A plurality of through holes 12a are formed in the frame member 12, and a fan 30 is disposed below the through holes 12a.

  The flat bed 14 is provided with a large number of small-diameter through holes 14c along the main scanning direction over substantially the entire region in the main scanning direction.

  Therefore, when the fan 30 is driven to rotate, the media located on the flat bed 14 can be sucked through the through hole 12a and the through hole 14c by the air flow accompanying the rotation. By this suction, the medium can be stably arranged on the flat bed 14, and high-quality printing and cutting can be performed by the ink jet head and the cutting head.

  Here, the flat bed 14 is the same as the structure of the conventional flat bed except that it is shortened in the sub-scanning direction in order to dispose the grid roller, and thus detailed description thereof is omitted.

  Further, the configuration of the frame member 12 and the front apron 20 and the configuration in which the front apron 20 is coupled to the downstream end portion 14b of the flat bed 14 in the sub-scanning direction are the same as those in the prior art, and thus detailed description thereof is omitted. To do.

  6A, 6B, and 6C are schematic perspective configuration explanatory views of main parts in a state where the flat bed 14, the rear apron 20, and the front apron 24 are removed from the platen device 10. FIG.

  FIG. 7A shows a perspective configuration explanatory view of an end support member 16a (to be described later) of the support members 16, and FIGS. 7B, 8A, and 8B. FIG. 2 shows a state in which the flat bed 14 and the rear apron 20 are attached to the end support member 16a.

  FIG. 9A shows a perspective configuration explanatory view of an intermediate support member 16b (to be described later) of the support members 16, and FIG. 9B shows a flat to the intermediate support member 16b. The attached state of the bed 14 and the rear apron 20 is shown.

  Hereinafter, the structure of the support member 16 and the rear apron 20 will be described in detail with reference to FIGS.

  First, as shown in FIG. 6, the support member 16 includes a pair of end support members 16 a disposed at both ends in the main scanning direction in the vicinity of the upstream end portion 14 a in the sub scanning direction of the flat bed 14 and the flat bed 14. The bed 14 includes a plurality of intermediate support members 16b disposed between the pair of support members 16a in the vicinity of the upstream end portion 14a in the sub-scanning direction.

  The end portion support member 16a and the intermediate portion support member 16b have the same configuration, but the configuration for supporting the grid roller 18 is different.

  Below, the structure of the edge part supporting member 16a and the intermediate part supporting member 16b is each demonstrated.

  As shown in FIGS. 7 to 8, the end support member 16a is a bottom portion 16a-1 fixed to the frame member 12, and a sub-portion formed from the end portion of the bottom portion 16a-1 on the upstream side in the sub-scanning direction. An upstream standing portion 16a-2 in the scanning direction, a downstream standing portion 16a-3 in the sub-scanning direction formed upright from an end on the downstream side in the sub-scanning direction in the bottom portion 16a-1, and a sub-scanning in the bottom portion 16a-1. Are supported by a reinforcing portion 16a-4 formed upright from a substantially intermediate position in the direction, an upstream standing portion 16a-2 in the sub-scanning direction, a downstream standing portion 16a-3 in the sub-scanning direction, and a reinforcing portion 16a-4. An annular bearing arrangement portion 16a-5 and an annular bearing 16a-6 arranged in the bearing arrangement portion 16a-5 are configured.

  A rear apron support portion 16a-7 that protrudes substantially horizontally toward the upstream side in the sub-scanning direction is formed in an area adjacent to the upstream standing portion 16a-2 in the sub-scanning direction in the bearing arrangement portion 16a-5. Yes. The rear apron support portion 16a-7 protrudes above a flat bed support portion 16a-8 described later.

  Further, a flat bed support portion 16a-8 for mounting and fixing the upstream end portion 14a of the flat bed 14 in the sub scanning direction is formed on the upper surface of the downstream side standing portion 16a-3 in the sub scanning direction. Yes.

  Both ends of the grid roller 18 are rotatably supported by bearings 16a-6 of the pair of end support members 16a.

  Next, as shown in FIG. 9, the intermediate portion support member 16 b is formed to rise from the bottom portion 16 b-1 fixed to the frame member 12 and the end portion of the bottom portion 16 b-1 on the upstream side in the sub-scanning direction. An upstream standing portion 16b-2 in the sub-scanning direction, a downstream standing portion 16b-3 in the sub-scanning direction formed up from an end of the bottom portion 16b-1 on the downstream side in the sub-scanning direction, and a sub-portion in the bottom portion 16b-1. And a reinforcing portion 16b-4 that rises from a substantially middle position in the scanning direction.

  The intermediate portion support member 16b includes a side wall portion 16b-5 supported by the sub-scanning direction upstream standing portion 16b-2, the sub-scanning direction downstream standing portion 16b-3, and the reinforcing portion 16b-4. A pair of rollers 16b-6 is rotatably disposed on the side wall portion 16b-5.

  An intermediate portion of the grid roller 18 is rotatably supported on the pair of rollers 16b-6.

  Further, at the upper portion of the upright standing portion 16b-2 in the sub-scanning direction, the upstream side in the sub-scanning direction is located at the same position as the vertical apex position of the rear apron support portion 16a-7 of the end support member 16a. The rear apron support part 16b-7 which protrudes substantially horizontally toward is formed. The rear apron support portion 16b-7 protrudes above a flat bed support portion 16b-8 described later.

  Further, a flat bed support portion 16b-8 for mounting and fixing the downstream end portion 14a in the sub scanning direction of the flat bed 14 is formed on the upper surface of the downstream side standing portion 16b-3 in the sub scanning direction. Yes.

  Next, as shown in FIGS. 7 to 9, when the rear apron 20 is assembled as a constituent member of the platen device 10 at the downstream end 20 b in the sub-scanning direction, the rear apron 20 A closing portion 20c disposed close to the surface and a distal end portion 20d slightly bent downward are formed on the distal end side of the closing portion 20c. The closing portion 20c extends to the upstream side in the sub-scanning direction from the upstream-side standing portion 16a-2 in the sub-scanning direction of the end support member 16a and the upstream-side standing portion 16b-2 in the sub-scanning direction of the intermediate portion support member 16b. The tip 20d is further extended to a position overlapping with the grit roller 10 in the up-down direction (up-down direction in FIG. 4) when viewed from the axial direction of the grit roller 10 (see FIG. 4).

  The closing portion 20c includes a contact portion 20c- that contacts the upper surface of the flat bed support portion 16a-8 and the flat bed support portion 16b-8 at a portion overlapping the end support member 16a and the intermediate portion support member 16b in the vertical direction. 1 is provided. Further, the plugging portion 20c is provided with an insertion portion 20e formed by cutting out a partial region thereof and bending it downward.

  Accordingly, the closing portion 20c and the insertion portion 20e are arranged in parallel along the main scanning direction at the downstream end portion 20b of the rear apron 20 in the sub scanning direction.

  As will be described later, the contact portion 20c-1 and the insertion portion 20e of the closing portion 20c are attached to the end support member 16a and the intermediate support member 16b on the frame member 12, and the end support member 16a and the intermediate portion 20e. When attaching the rear apron 20 to the part support member 16b, the rear apron support parts 16a-7 and 16b-7 are dimensioned so as to be sandwiched between the contact part 20c-1 of the closing part 20c and the insertion part 20e. Is set.

  The rear apron 20 has the same configuration as that of the conventional rear apron except that a closing portion 20c, a tip portion 20d, and an insertion portion 20e are formed at the downstream end portion 20b in the sub-scanning direction. The detailed description of is omitted.

  An example of a method for assembling the flat bed apparatus 10 in the above configuration will be described.

  First, both ends of the grid roller 18 are rotatably supported by bearings 16a-6 of the pair of end support members 16a, and the intermediate portion of the grid roller 18 is placed on the pair of rollers 16b-6 of the intermediate support member 16b. The end support member 16a and the intermediate support member 16b are respectively fixed at predetermined positions on the frame member 12 using a coupling member such as a screw or a screw while being rotatably supported.

  Next, the upstream end portion 14a of the flat bed 14 in the sub-scanning direction is placed on the flat bed support portion 16a-8 of the end portion support member 16a and the flat bed support portion 16b-8 of the intermediate portion support member 16b. And it fixes on the flat bed support parts 16a-8 and 16b-8 using coupling members, such as a screw and a screw.

  As a result, the downstream end portion 14 a of the flat bed 14 in the sub-scanning direction is disposed close to the peripheral surface of the grid roller 18.

  A front apron 24 may be attached to the downstream end 14b of the flat bed 14 in the sub-scanning direction by a known method, and the front apron 24 may be fixed to the fixed system member by a known method.

  Next, the insertion part 20e of the rear apron 20 is engaged with the end support member 16a and the intermediate support member 16b, and the rear apron 20 is supported by the end support member 16a and the intermediate support member 16b.

  More specifically, the rear apron support portion 16a-7 and 16b-7 are held between the closing portion 20c and the insertion portion 20e of the rear apron 20, and the rear apron 20 is connected to the end support member 16a. The intermediate part supporting member 16b is supported.

  Thereby, the contact part 20 c-1 of the closing part 20 c of the rear apron 20 is arranged close to the peripheral surface of the grid roller 18.

  The upstream end of the rear apron 20 in the sub-scanning direction may be fixed to the fixed system member by a known method.

  Further, when the rear apron 20 is supported and fixed to the end support member 16a and the intermediate support member 16b, the shielding member 28 is urged and elastically deformed by the lower surface 20a of the rear apron 20, so that the rear apron 20 The lower surface 20a and the shielding member 28 come into pressure contact with each other.

  Thereby, since the vertical wall 26 and the shielding member 28 can substantially block the air flow on the lower surface 20a of the rear apron 20, the suction force of the medium by the fan 30 can be stably exhibited. It becomes like this.

  Therefore, in the platen device 10, the rear apron 20 can be easily supported by the support member 16 by engaging the insertion portion 20e with the rear apron support portions 16a-7 and 16b-7, and the medium is supported by the closing portion 20c. It can prevent falling into the gap between the grid roller 18 and the rear apron 20.

  More specifically, since the rear apron support portions 16a-7 and 16b-7 are held between the contact portion 20c-1 of the closing portion 20c and the insertion portion 20e, the rear apron 20 is securely supported by the support member 16. Can be supported.

  Further, in the platen device 10, the height of the rear apron support portions 16a-7 and 16b-7 and the flat bed support portions 16a-8 and 16b-8 in the end support member 16a and the intermediate support member 16b is determined. By appropriately setting the dimensions, the positional relationship in the high direction between the flat bed 14 and the rear apron 20 can be adjusted as appropriate.

  Thereby, smooth conveyance of the media from the rear apron 20 to the flat bed 14 can be ensured.

  Further, in the platen device 10, the flow of air on the lower surface 20 a of the rear apron 20 can be more reliably blocked by adjusting the height dimension of the vertical wall 26 and the shielding member 28.

  As described above, the platen device 10 according to the present invention includes the end support member 16a and the intermediate portion with a simple configuration in which the closing portion of the rear apron 20 is inserted into the rear apron support portions 16a-7 and 16b-7. The rear apron 20 can be easily attached to the support member 16b.

  The embodiment described above may be modified as shown in the following (1) to (4).

  (1) In the above-described embodiment, the case where the front apron 24 is attached to the flat bed 14 has been described. However, the present invention is not limited to this, and the front apron 24 is attached to the flat bed 14. It does not have to be.

  (2) In the above-described embodiment, the case where the medium on the flat bed 14 is sucked by the fan 30 has been described. However, the present invention is not limited to this, and the medium on the flat bed 14 is sucked. It does not need to have a configuration. That is, the platen device 10 may not include the through hole 14c formed in the flat bed 14, the through hole 12a formed in the frame member 12, the fan 30, the vertical wall 26, and the buffer member 28.

  (3) In the above-described embodiment, the detailed description of the arrangement position and the number of arrangement of the intermediate support member 16b in the main scanning direction is omitted, but the intermediate support member 16b has various design conditions. In consideration of the above, the arrangement position and the number of arrangements may be determined appropriately.

  (4) You may make it combine suitably the embodiment shown above and the modification shown in said (1) thru | or (3).

  The present invention can be used as a platen device in various apparatuses such as an ink jet printer and a cutting plotter.

  DESCRIPTION OF SYMBOLS 10 Platen apparatus, 12 Frame member, 12a Through-hole, 14 Flat bed (bed), 14c Through-hole, 16 Support member, 16a End part support member, 16b Middle part support member, 16a-7 Rear apron support part, 16b-7 Rear apron support part, 16a-8 flat bed support part, 16b-8 flat bed support part, 18 grid roller, 20 rear apron, 20c closing part, 20c-1 abutting part (closing part), 20e insertion part, 24 front Apron, 26 vertical wall, 28 shielding member, 30 fans

Claims (5)

A bed in which the medium is arranged, a rear apron for guiding the medium to the bed, and an end of the bed on the upstream side in the transport direction of the medium and an end of the rear apron on the downstream side in the transport direction of the medium A platen device provided with a grid roller that is arranged in the conveyance direction and conveys the medium in the conveyance direction,
A support member for rotatably supporting the grid roller;
The support member includes a rear apron support portion provided at the upstream end of the support member in the transport direction,
The rear apron includes an insertion portion that engages with the rear apron support portion,
The platen device, wherein the insertion portion of the rear apron is engaged with the support member, and the support member supports the rear apron. The platen apparatus according to claim 1,
The rear apron includes a closing portion that is arranged in parallel with the insertion portion and is disposed in the vicinity of the peripheral surface of the grid roller,
The platen device, wherein the rear apron support portion of the support member is sandwiched between the closing portion and the insertion portion of the rear apron. The platen apparatus according to any one of claims 1 and 2,
The support member includes a bed support portion that supports an end portion of the bed on the upstream side in the transport direction on the downstream side in the transport direction,
An end portion of the bed on the upstream side in the transport direction is supported by the bed support portion of the support member. The platen device according to any one of claims 1, 2, or 3,
On the lower side of the rear apron, a vertical wall erected on the upper side and a shielding member disposed on the upper side end of the vertical wall,
When the rear apron engages with the support member, the shielding member is urged by the lower surface of the rear apron. The platen device according to claim 4, wherein
The platen device, wherein the shielding member is made of an elastically deformable material.