JP2000327172A - Carrier path forming member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent noise caused by a recording medium by forming a plurality of recessed parts on two side walls extending from upper surfaces of the side walls up to bottom walls in a carrier path forming member formed out of the bottom walls extending in the intersection direction of the carrier direction and having holes formed and the two side walls opposite to each other extending in the intersection direction. SOLUTION: In a platen 70 (carrier path forming member), a plurality of grooves 72 extending in the intersection direction of the carrier direction are formed. These grooves 72 are formed by bottom walls 76 and two opposed side walls 78, 80. On both of the side walls 78, 80, a plurality of recessed parts 74 extending from each upper surface 78a, 80a up to the bottom walls 76 are formed. When a gap 36 is sectioned between an end part 34a and an upper surface 78a of the side wall 78 when the end part 34a of recording paper 34 passes on a hole 76a of the bottom wall 76, air is sucked from also the recessed parts 74 and suction force for sucking the end part 34a of recording paper 34 is weakened. Therefore, generation of noise by repeatingly contacting and separating of the end part 34a of recording paper 34 with/from the bottom walls 76 and both the side walls 78, 80 for short time can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conveying path forming member for conveying a recording medium.

[0002]

2. Description of the Related Art As one of output devices of computers and workstations, there is known an ink jet type image forming apparatus which forms an image on a recording medium such as recording paper by discharging ink. With reference to FIG. 8, a conventional ink jet type image forming apparatus will be described.

FIG. 8 is a perspective view showing a schematic configuration of a plotter which is an example of a conventional ink jet type image forming apparatus.

[0004] The plotter 10 is moved in the direction of arrow A (transfer direction).
And a platen 12 on which recording paper (not shown) to be conveyed is placed. Above the platen 12, two guide rails 14 are extended in parallel with the platen 12. A carriage 16 that freely reciprocates in the direction of arrow B (a direction perpendicular to the transport direction) by a motor (not shown) and a belt (not shown) is provided on the two guide rails 14 by a slide bearing (not shown). Zu) is attached through.

A print head 18 is mounted on the carriage 16, and a plurality of ink discharge ports (not shown) for discharging ink are formed on an ink discharge surface (not shown) of the print head 18. . The print head 18 has five ink cartridges 18K, 18K (black), 1
8C (cyan), 18M (magenta) and 18Y (yellow) are detachably mounted.

When the print head 18 is located above the platen 12, an area in front of the ink ejection port surface of the print head 18 is an image forming area where an image is formed. The ink is ejected from the ink ejection port at a predetermined timing on the portion located at a position, and an image for one band is formed. Thereafter, the recording paper is conveyed by the width of one band by the pinch roller 22 and the conveyance roller 24 held by the holding arm 20 and stopped. Ink is ejected from the ink ejection port based on the image, and an image is formed on a portion of the recording paper that is newly located in the image forming area. By repeating such an operation, an image is formed on the recording paper.

[0007] A plurality of grooves 26 extending in the direction of arrow B are formed in the platen 12. The groove 26 will be described with reference to FIGS.

FIG. 9 is a cross-sectional view showing one groove cut along the direction of arrow A, and FIG. 10 is a cross-sectional view showing the movement of the end of the recording medium passing through this groove.

On the upper surface 12a of the platen 12, there are formed a plurality of grooves 26 extending in the direction of arrow B (a direction orthogonal to the direction of arrow A, see FIG. 8). Each groove 26 extends in the direction of arrow B and has a bottom wall 28 in which a hole 28a is formed, and two side walls 30 and 32 extending in the direction of arrow B and facing each other.
It is composed of Below the platen 12, a bottom wall 28
Suction fan (not shown) that sucks air from the hole 28a
Is arranged. The suction fan is for keeping a portion of the recording paper 34 on the platen 12 in close contact with the platen 12 so as to keep the distance from the print head 18 constant. By keeping the distance between the print head 18 and the recording paper constant, the quality of the image formed on the recording paper 34 can be kept constant.

[0010]

The recording paper 34
When the end 34a passes above the hole 28a of the bottom wall 28, a gap 36 may be formed between the end 34a and the upper surface 32a of the side wall 32 (sometimes the side wall 30). . When such a gap 36 is formed, the gap 36
, The suction force when the suction fan sucks the end 34a located near the gap 36 becomes unstable. As a result, as shown in FIGS. 9 and 10, the end 34 a comes into contact with or separates from (not in contact with) the bottom wall 28 and the side wall 32 of the groove 26. When contact and non-contact are repeated in a short time in this manner, a minute sound is generated, which causes noise.

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a conveying path forming member which prevents noise caused by an end of a recording medium.

[0012]

According to another aspect of the present invention, there is provided an image forming apparatus for conveying a recording medium in a predetermined conveying direction to form an image on the recording medium. In a conveying path forming member through which a recording medium passes, the conveying medium has a groove formed by a bottom wall having a hole extending in the cross direction intersecting the conveying direction and having two side walls extending in the cross direction and facing each other. And a plurality of recesses formed on each of the two side walls and extending from the upper surface of the side wall to the bottom wall.

Here, (2) the groove may have a length equal to or longer than the length of the recording medium conveyed on the groove in a direction perpendicular to the conveying direction.

(3) The plurality of recesses may be formed at intervals of 10 mm or more and 50 mm or less in the cross direction.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a conveying path forming member according to an embodiment of the present invention.

Referring to FIG. 1, a plotter in which the conveying path forming member of the present invention is incorporated will be described.

FIG. 1 is a perspective view schematically showing a plotter in which a conveying path forming member of the present invention is incorporated. In this figure, the same components as those shown in FIGS. 8 to 10 are denoted by the same reference numerals.

An elongated rectangular parallelepiped housing 50 is incorporated in the plotter 40. The upper wall 52 of the housing 50 has a platen 70 in place of the platen 12 (see FIG. 8).
(See FIG. 3) is fixed. The schematic configuration of the housing 50 will be described with reference to FIG.

FIG. 2 is a perspective view showing a schematic configuration of the housing.

The housing 50 is closed at both longitudinal ends by a left wall 54 and a right wall 56. Further, a large number of holes (not shown) are formed in the upper wall 52. In the lower wall 58, large holes 58a (two in FIG. 2) are formed.
A suction fan 60 is fixed below a. Also,
The housing 50 has a front wall 59 and a rear wall (not shown),
The housing 50 includes the upper wall 52, the left wall 54, and the right wall 5 described above.
6, a hollow portion surrounded by the lower wall 58, the front wall 59, and the rear wall is formed. When the suction fan 60 rotates, air is sucked through the holes in the upper wall 52 and the holes 58a in the lower wall 58.

Referring to FIG. 3, FIG. 4 and FIG.
The platen 70 fixed to the upper wall 52 will be described.

FIGS. 3A and 3B show a part of the platen. FIG. 3A is a perspective view, and FIG. 3B is a cross-sectional view of FIG. 4A and 4B show a part of the groove, FIG. 4A is a perspective view, and FIG. 4B is a sectional view taken along line DD of FIG. 5A and 5B show another example of the hole formed in the groove. FIG. 5A is a perspective view, and FIG. 5B is a sectional view taken along line EE of FIG.

As shown in FIG. 3, a platen 70 (an example of a conveying path forming member according to the present invention) has an arrow B direction (an example of an intersecting direction intersecting the conveying direction according to the present invention). A plurality of grooves 72 extending in a direction orthogonal to the direction of arrow A.). The groove 72 is similar to the groove 26 of the plotter 10 shown in FIG. 8, except that a concave portion 74 is formed. The length of the groove 72 (length in the direction of arrow B) is equal to or greater than the width of the recording medium conveyed over the groove 72 (length in the direction of arrow B). That is, the groove 7
The length 2 is equal to or longer than the maximum width of the recording medium that can be used by the plotter 40.

The groove 72 has a bottom wall 76 extending in the direction of arrow B.
And two side walls 78 and 80 facing each other. A large number of holes 76a are formed in the bottom wall 76.
3 and 4 show an example in which the hole 76a is formed in the bottom wall 76, but as shown in FIG.
A hole 76b extending to (or the side wall 80) may be formed.

Also, as shown in FIG.
Respectively, the upper surfaces 78a, 80a of the side walls 78, 80, respectively.
A plurality of concave portions 74 extending from the bottom wall 76 to the bottom wall 76 are formed. The recess 74 is recessed from the side walls 78 and 80 by a depth of about several mm, and the angle of inclination of the recessed portion is substantially the same as the angle of inclination of the side walls 78 and 80.
In each of the side walls 78 and 80, recesses 74 are formed at intervals of 10 mm or more and 50 mm or less in the direction of arrow B.

Referring to FIG. 6, the operation of the recess 74 will be described.

FIG. 6 is a sectional view showing a state in which the end of the recording paper passes above the hole in the bottom wall.

The end 34a of the recording paper 34 is
6a, the end 34a and the side wall 7
The gap 36 may be formed between the upper surface 8a (which may be the side wall 80) and the upper surface 78a. When such a gap 36 is formed, air is sucked from the gap 36, so that the end 34 a located near the gap 36 is connected to the suction fan 6.
0 (see FIG. 2) may cause an unstable suction force when suctioning. However, since the concave portion 74 is formed,
Even if the gap 36 is formed, not only the gap 36 but also the recess 7 is formed.
Air is also sucked from 4. As a result, the suction force for sucking the end 34a of the recording paper 34 is weakened, and the end 34a is hardly sucked. Therefore, the end 34 a is kept away from the bottom wall 76 and the side walls 78 and 80 due to the “hip” of the recording paper 34. Therefore, a faint sound as described with reference to FIGS. 9 and 10 is not generated.

Referring to FIG. 7, a modified example of the shape of the concave portion 74 will be described.

FIGS. 7A and 7B show a part of a platen 90 in which a concave portion of another shape is formed. FIG. 7A is a perspective view, and FIG.
FIG. 2 is a sectional view taken along line FF of FIG. 7, the same components as those shown in FIG. 3 are denoted by the same reference numerals.

As described above, the inclination angle of the wall in the recessed portion of the concave portion 74 shown in FIG. 3 is almost the same as the inclination angle of the side walls 78 and 80. However, the wall 92 a in the recessed portion of the concave portion 92 formed in the groove 72 of the platen 90 rises almost vertically from the bottom wall 76. Thus wall 9
Even when 2a is formed, the operation of the concave portion 92 is the same as the operation of the concave portion 74.

[0032]

As described above, in the conveying path forming member of the present invention, when the recording medium passes through the conveying path forming member, the recording medium passes through the conveying path forming member while being in close contact with the conveying path forming member. A suction fan may be arranged below. In such a case, when the suction fan is rotated, air is sucked downward from the hole in the bottom wall, and the recording medium passing through the conveyance path forming member comes into close contact with the conveyance path forming member. However, when the end of the recording medium passes above the hole in the bottom wall, a gap may be formed between the end and the upper surface of the side wall. When such a gap is formed, air is sucked from the gap, and the suction force when the suction fan sucks the end located near the gap becomes unstable. As a result, this end comes into contact with or separates from (non-contacts with) the bottom and side walls of the groove. If the contact and non-contact are repeated in a short time, a minute sound is generated, which causes noise. However, the plurality of recesses described above are formed in the transport path forming member of the present invention. For this reason,
Even if the above gap is formed, air is sucked not only from the gap but also from the plurality of recesses. As a result, the suction force for sucking the end of the recording medium located near the gap is weakened, and the end of the recording medium is hardly sucked. Therefore, this end is kept away from the bottom and side walls of the groove, and does not generate sound and does not cause noise.

Here, when the groove has a length equal to or longer than the length of the recording medium conveyed on the groove in a direction perpendicular to the conveying direction, the conveying path forming member is conveyed. It is possible to prevent the generation of minute sounds from the ends of all the recording media.

In the case where the plurality of recesses are formed at intervals of 10 mm or more and 50 mm or less in the cross direction, when the interval between adjacent recesses in the cross direction is too large, the recording medium ends. Since the suction force at the time of sucking the air does not decrease, a minute noise may be generated. On the other hand, when the interval between adjacent recesses in the cross direction is too small,
Since the suction force at the time of suctioning the end portion of the recording medium is excessively reduced, the recording medium may not be able to adhere to the conveyance path forming member. However, the plurality of recesses are more than 10 mm in the cross direction.
If the recording medium is formed at an interval of 0 mm or less, the suction force at the time of sucking the end of the recording medium is appropriately weakened, so that the generation of minute noise can be reliably prevented, and the recording medium can be reliably transferred to the conveyance path forming member. It is made to adhere to.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a plotter in which one embodiment of a transport path forming member of the present invention is incorporated.

FIG. 2 is a perspective view showing a schematic configuration of a housing.

3A is a perspective view showing a part of a platen, and FIG. 3B is a cross-sectional view taken along the line CC of FIG. 3A.

4A is a perspective view showing a part of a groove, FIG.
(B) is DD sectional drawing of (a).

5A is a perspective view showing another example of the hole formed in the groove, and FIG. 5B is a sectional view taken along line EE of FIG. 5A.

FIG. 6 is a cross-sectional view showing a state in which an end of the recording paper passes above a hole in a bottom wall.

7A is a perspective view showing a part of a platen on which a concave portion having another shape is formed, and FIG. 7B is a perspective view of FIG.
It is sectional drawing.

FIG. 8 is a perspective view showing a schematic configuration of a plotter which is an example of a conventional ink jet type image forming apparatus.

FIG. 9 is a sectional view showing one groove cut along the direction of arrow A;

FIG. 10 is a sectional view showing the movement of the end of the recording medium while passing through the groove of FIG. 9;

[Explanation of symbols]

 40 Plotter 70, 90 Platen 72 Groove 74, 92 Recess 76 Bottom wall 76a Hole 78, 80 Side wall 78a, 80a Top surface of side wall

Claims (3)

[Claims] 1. An image forming apparatus which conveys a recording medium in a predetermined conveying direction to form an image on the recording medium, and a bottom wall having a hole extending in a crossing direction intersecting the conveying direction and having the hole. A conveying path forming member, through which a recording medium passes, having a groove formed by two side walls extending in the direction and facing each other, a plurality of grooves formed on each of the two side walls extending from the upper surface of the side wall to the bottom wall. A conveyance path forming member having a concave portion. 2. The recording medium according to claim 1, wherein the groove has a length equal to or longer than a length of a recording medium conveyed on the groove in a direction perpendicular to the conveying direction. Conveying path forming member. 3. The conveying path forming member according to claim 1, wherein the plurality of recesses are formed at intervals of 10 mm or more and 50 mm or less in the cross direction.