JPH07314826A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To obtain a suitable sheet conveying operation while employing a double end feeding type for conveying the recording sheet by holding the width direction both ends of the sheet by a drive belt and a driven belt. CONSTITUTION:A double end feeding type conveys a recording sheet by holding the width direction both ends of the sheet by a drive belt 1 and a driven belt 2, and has engaging holes 7, 8 formed at the belts 1, 2 and protrusions 9 to be engaged with the engaging holes 7, 8 and formed on the outer periphery of a drive side pulley 4 having a the belt 1 passed about, at a predetermined pitch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a facsimile, a copying machine,
The present invention relates to an inkjet recording device used as an output device of a computer.

[0002]

2. Description of the Related Art An ink jet recording apparatus has a recording head provided with a large number of nozzles (ink ejection ports), and ejects ink from the nozzles to record an image on a recording sheet conveyed by a sheet conveying means. It is composed.

Conventionally, as a sheet conveying means in this ink jet recording apparatus, generally, Japanese Patent Laid-Open No. 1856/1991.
A belt is used as shown in No. 61 and JP-A-5-330037.

Further, as a belt conveying system suitable for the double-sided recording system, a drive belt driven by a motor and a driven belt for transmitting a rotational force to the drive belt on both sides in the paper width direction. It is conceivable to adopt a both-ends feeding system in which both ends of the recording paper in the width direction are sandwiched between the driving and driven belts and conveyed.

[0005]

However, in the belt conveying system, a difference in diameter on both sides in the axial direction of the pulley and a speed difference on both sides in the belt width direction due to the slip of the belt with respect to the pulley cause a meandering of the belt. There is a problem that it will occur.

Particularly, in the case of the above-mentioned double-end feeding method, when the drive belt is meandered, the meandering is transmitted to the driven belt, and the driven belt is also likely to meander. Since there is a possibility that there will be a speed difference between the driven and driven belts, there is the problem that paper conveyance defects are likely to occur. Was becoming.

Therefore, the present invention provides an ink jet recording apparatus capable of ensuring an appropriate paper conveying action while adopting a double-sided feeding system in which both widthwise end portions of a recording paper sheet are held and conveyed by both driving and driven belts. To do.

[0008]

According to a first aspect of the present invention, there is provided an ink jet recording apparatus for recording an image by ejecting ink from nozzles of a recording head onto a recording sheet conveyed by a conveyor belt. Both driving and driven belts are provided to sandwich both edges of the recording paper in the width direction from the front and back sides and convey it.The driving belt has an engaging hole in the part that protrudes outside the width of the recording paper all around the belt. And a projection that meshes with the engagement hole is provided at a constant pitch in the circumferential direction on the outer periphery of the drive pulley on which the drive belt is hung, at least at one end side of the drive belt. is there.

According to a second aspect of the present invention, in the structure of the first aspect, engagement holes are provided in both the driving and driven belts, and at least one of the driving and driven belts has a pulley on at least one end side thereof. A protrusion that meshes with the engaging hole of the belt is provided.

According to a third aspect of the present invention, in the configuration of the second aspect, the height dimension of the protrusion is set to be larger than the total thickness dimension of both the driving and driven belts, and the protrusion is opposed to the pulley. On the outer peripheral surface of the pulley, a concave groove into which the tips of the protrusions protruding from the engaging holes of the both belts are fitted is provided over the entire circumference.

According to a fourth aspect of the present invention, in any one of the first to third aspects, at least the driving belt of the driving and driven belts sandwiches both widthwise end portions of the recording sheet to perform a conveying action. It is stretched in a continuous state by a two-sided transport section and a bridge section that connects the two-sided transport sections.

[0012]

According to the first aspect of the invention, the engagement of the projection and the engagement hole prevents the drive belt from slipping with respect to the drive pulley, thereby preventing the drive belt from meandering.

Accordingly, the meandering of the driven belt due to the meandering of the driving belt and the speed difference between the driving and driven belts are prevented from occurring, so that an appropriate sheet conveying action is performed.

According to the second aspect of the present invention, the protrusion engages over the engaging holes of both the driving and driven belts, and the meshing action is performed on both belts simultaneously. The speed difference between the two belts is more reliably prevented from occurring.

Furthermore, according to the third aspect of the present invention, the height dimension of the protrusion is not less than the total thickness dimension of both the driving and driven belts and does not hit the bottom surface of the concave groove. The precision becomes gentler, and the manufacturing and assembling becomes easier accordingly.

On the other hand, according to the structure of claim 4, at least on the driving side, one belt is continuously stretched across both sides in the sheet width direction, and the sheet is fed by the both sides by the both-side feeding section of the belt. The carrying action is performed.

Therefore, in addition to the meandering of the entire belt being prevented by the meshing action of the projection and the engaging hole, the speed difference (difference in the sheet feeding speed) on both sides of the belt is prevented.

[0018]

【Example】

First Embodiment (see FIGS. 1 to 4) In FIG. 1, A is a paper transport mechanism, which is a recording paper (hereinafter, simply referred to as paper) P supplied from a paper supply unit (not shown).
However, the sheet transport mechanism A transports the sheet on the transport line R from the top to the bottom of the drawing to move between the double-sided print heads B1 and B2 having a large number of nozzles (ink ejection ports),
After recording, it is dried by a warm air type drying device C equipped with a heater and a fan (not shown).

The paper transport mechanism A includes both driving and driven belts 1 and 2 arranged on both sides of the transport line R.

The drive belt 1 is stretched between the upper and lower pulleys 3 and 4 on the drive side, and the driven belt 2 is stretched between the upper and lower pulleys 5 and 6 on the driven side. One of the belts is driven by a motor (not shown) to rotate the drive belt 1, and this rotational force is transmitted to the driven belt 2 by the parts 1a and 2a which are basically in phase contact with each other, so that both belts 1 and 2 rotate simultaneously. To do.

The drive and driven belts 1 and 2 are
As shown in FIG. 3, they are arranged on both sides in the width direction of the paper, and both ends of the paper P in the width direction are sandwiched between the belts 1 and 2 and are conveyed by a double-end feeding method.

The belts 1 and 2 are arranged in such a manner that the ends on the outer side in the width direction project outside the width of the paper P as shown in FIG. 3, and the belts 1 and 2 are arranged as shown in FIGS. Vertically long rectangular engaging holes (through holes) 7 ..., 8 ... Are provided at a constant pitch over the entire circumference of the belt at the end portion protruding outside the paper width.

On the other hand, on the outer circumference of the end portion of the lower pulley 4 on the driving side, which projects outside the sheet width, a large number of protrusions 9 ... Having a shape and size capable of engaging with the engaging holes 7 and 8 are engaged. The holes 7 ..., 8 ... Are provided at the same pitch.

The height dimension h of the protrusions 9 ... In relation to the thickness dimension t of both belts 1 and 2,

[0025]

## EQU1 ## t <h.ltoreq.2t (provided that the thickness t of both belts 1 and 2 is the same and the gap between both belts is 0).

As a result, the projections 9 engage with the engaging holes 7 of the drive belt 1 in a state where the front half is projected, and the protruding front half is engaged with the engaging hole 8 of the driven belt 2.
Mesh with ...

That is, the projections 9 are formed so as to engage with each other while straddling the engagement holes 8 ...

The engagement of the projections 9 with the engagement holes 7, ..., 8 prevents the drive belt 1 from slipping on the drive pulleys 3 and 4, and the driven belt 2 is also driven by the drive pulley 4. Therefore, the slip of the driven belt 2 with respect to the drive belt is prevented.

As a result, both the driving and driven belts 1,
Since the meandering of 2 and the speed difference between the belts 1 and 2 are prevented from occurring, an appropriate sheet conveying operation is performed.

Second Embodiment (See FIG. 5) Only the differences from the first embodiment will be described.

In the second embodiment, the height dimension h of the protrusions 9 ...
Is set to be larger than the total thickness dimension 2t of both belts 1 and 2, while a groove 6a is provided on the outer peripheral surface of the driven side lower pulley 6 at a position corresponding to the engaging holes 8 ... The protrusions 9 are engaged with the engaging holes 7 and 8 of the belts 1 and 2 and the tip ends of the protrusions 9 protrude from the engaging holes 8 and are fitted into the concave grooves 6a.

According to this structure, the height dimension h of the protrusions 9 ...
Is 2t or more and has a size that does not hit the bottom surface of the concave groove 6a, the dimensional accuracy becomes gentle,
Therefore, manufacturing and assembling becomes easy.

Third Embodiment (see FIG. 6) In the third embodiment, only the driving belt 1 is provided with the engaging holes 7 ..., On the other hand, the height dimension h of the protrusions 9 ... It is set to half of that of the embodiment, that is, equal to or less than the thickness t of the drive belt 1.

According to this structure, the projections 9 ... And the engagement holes 7 ...
The meshing action is performed only by this, and by this meshing action, the slip of the drive belt 1 with respect to the drive pulleys 3, 4 is directly suppressed, and the meandering of the drive belt 1 is prevented.

Further, since the meandering of the driving belt 1 is prevented, a phenomenon resulting from this, that is, the meandering is transmitted from the driving belt 1 to the driven belt 2, the driving belt 1
The rotational force of 1 is not transmitted to the driven belt 2 well, and there is no risk of a speed difference between the driven and driven belts 1 and 2.

Fourth Embodiment (See FIG. 7) In the fourth embodiment, the drive belt 1 is constructed as a series of both sides (single belt).

That is, as guide means for the drive belt 1, the horizontal guide pulleys 10, 1 are provided on both sides in the paper width direction separately from the drive-side upper and lower pulleys 3, 4.
0 and vertical guide pulleys 11 and 11, and the horizontal and vertical guide pulleys 10, ..., 11 drive belt 1 to (a) transport section T1, on both sides in the paper width direction.
T2 is formed, and (b) the bridge portion S in which the both-side transport portions T1 and T2 are bridged between the vertical guide pulleys 11 on both sides.
1, S2 are stretched in a continuous state, and both-side transport portions T1, T2 are configured to feed both ends of the paper P.

With this structure, meandering of the entire drive belt 1 is prevented by the meshing action of the projections 9 ... And the engagement hole 7, and a speed difference (difference in paper feed speed) on both sides of the belt does not occur. Therefore, it is possible to prevent the sheet P from being obliquely conveyed.

In this structure, the protrusions 9 ...
As shown in the figure, it may be provided on both drive side lower pulleys 4 and 4 on both sides of the belt, or may be provided on only one side.

Further, this one-belt structure has a driven belt 2
Can also be adopted.

Other Embodiments (1) In the above embodiment, the protrusions 9 ...
However, the protrusions 9 ... May be provided on the upper pulley 3 or the upper and lower pulleys 3 and 4.

(2) In the case of the structure of the third embodiment (FIG. 6), the relation between the height dimension h of the protrusions 9 ... And the belt thickness dimension t is h> t, and the driven belt 2 side is provided with an engaging hole. An escape groove (concave groove) may be provided for the tip of the protrusion protruding from 7.

Alternatively, h <t may be set, and the engagement holes 7 may be concave grooves instead of through holes.

[0044]

As described above, according to the first aspect of the present invention, in the double-sided feed system in which both ends of the recording sheet in the width direction are sandwiched and conveyed by the driving and driven belts, the driving belt is provided with an engaging hole, Since the protrusions that engage with the engaging holes are provided at a constant pitch on the outer circumference of the driving pulley on which the belt is hung, the engagement of the protrusions with the engaging holes can prevent the driving belt from slipping on the driving pulley. It is possible to prevent the drive belt from meandering.

Therefore, since it is possible to prevent the meandering of the driven belt due to the meandering of the driving belt and the occurrence of a speed difference between the driving and driven belts, it is possible to secure an appropriate sheet conveying action.

According to the second aspect of the present invention, the protrusion is engaged over the engaging holes of both the driving and driven belts, and the meshing action is performed on both belts simultaneously. Therefore, the meandering prevention of the driving and driven belts is prevented. The effect and the effect of preventing the occurrence of the speed difference between the both belts become more reliable.

Further, according to the invention of claim 3, the height dimension of the projection is not less than the total thickness dimension of both the driving and driven belts and does not hit the bottom surface of the concave groove. The precision becomes gentler, and the manufacturing and assembling becomes easier accordingly.

On the other hand, according to the invention of claim 4, at least on the driving side, one belt is continuously stretched across both sides in the sheet width direction, and the sheet is fed by both sides by the both-side feeding section of the belt. Since it is configured to carry, the meandering of the entire belt is prevented by the meshing action of the projection and the engaging hole, and also the occurrence of speed difference (difference in paper feed speed) on both sides of the belt is prevented. You can

Therefore, it is possible to prevent the sheet from being conveyed obliquely.
It is possible to more reliably achieve the intended purpose of ensuring an appropriate paper transport action.

[Brief description of drawings]

FIG. 1 is a front view showing a schematic configuration of a paper transport mechanism in an inkjet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of the same mechanism.

FIG. 3 is a partial perspective view of the same.

FIG. 4 is a partially enlarged view of FIG.

FIG. 5 is a view, corresponding to FIG. 4, showing a second embodiment of the present invention.

FIG. 6 is a view corresponding to FIG. 4, showing a third embodiment of the present invention.

FIG. 7 is a perspective view of a paper transport mechanism showing a fourth embodiment of the present invention.

[Explanation of symbols]

 B1, B2 Recording head 1 Drive belt 2 Driven belt 3 Drive side upper pulley 4 Drive side lower pulley 5 Driven side upper pulley 6 Driven side lower pulley 7, 8 Engagement holes in both belts 9 Protrusion T1, T2 One Both sides of belt system S1, S2 Same bridge 6a Groove

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shizushi Kado 1-2-2 Tamatsukuri, Chuo-ku, Osaka City Mita Engineering Co., Ltd. (72) Kenichi Sabu 1-2-2 Tamatsukuri, Chuo-ku, Osaka No. Mita Engineering Co., Ltd. (72) Inventor Hiromi Kosaka 1-228 Tamazuzo, Chuo-ku, Osaka Mita Engineering Co., Ltd. (72) Koichi Baba 1-22 Tamatsukuri, Chuo-ku, Osaka Mita Kogyo Co., Ltd. (72) Inventor Masayuki Ishii 1-228 Tamatsukuri, Chuo-ku, Osaka Mita Kogyo Co., Ltd. (72) Yoshiko Kawachi 1-228 Tamatsukuri, Chuo-ku, Osaka Mita Kogyo Within the corporation

Claims (4)

[Claims] 1. An ink jet recording apparatus for recording an image by ejecting ink from nozzles of a recording head onto a recording sheet conveyed by a conveying belt, wherein the conveying belt serves as the conveying belt from both front and back sides in the width direction. Both driving and driven belts that pinch and convey are provided. Among these, the driving belt is provided with engaging holes at a portion protruding outside the width of the recording paper at a constant pitch over the entire circumference of the driving belt. An ink jet recording apparatus, characterized in that at least one end side of the belt, projections that engage with the engaging holes are provided at a constant pitch in the circumferential direction on the outer periphery of the drive pulley on which the drive belt is hung. 2. The ink jet recording apparatus according to claim 1, wherein engaging holes are provided in both the driving and driven belts, and at least one of the driving and driven belts has a pulley on at least one end side thereof. An ink jet recording apparatus, characterized in that a projection that meshes with the engaging hole is provided. 3. The ink jet recording apparatus according to claim 2, wherein the height dimension of the protrusion is set to be larger than the total thickness dimension of both the driving and driven belts, and the pulley opposite to the pulley provided with this protrusion. 2. An ink jet recording apparatus, wherein a concave groove into which a tip end portion of a protrusion protruding from the engaging holes of the both belts is fitted is provided on an outer peripheral surface of the entire peripheral surface of the above. 4. A driving belt and a driven belt, wherein at least the driving belt is composed of a pair of both side conveying portions that perform a conveying action by sandwiching both widthwise end portions of the recording sheet, and a bridge portion that connects the both side conveying portions. The ink jet recording apparatus according to any one of claims 1 to 3, wherein the ink jet recording apparatus is stretched in a state.