JPH0620962B2 - Sheet transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a sheet conveying device capable of easily releasing a pressure contact state between a conveying rotating body for conveying a sheet and a pressing member for pressing the sheet against the conveying rotating body. It is a thing.

<Prior Art> Generally, a recording apparatus such as a printer is configured to perform recording while conveying a recording sheet. However, in conveying the recording sheet, conventionally, the recording sheet is rotated according to recording. In most cases, a pinch roller is pressed against the roller, and the recording sheet is conveyed along the circumferential surface of the conveying roller while sandwiching the recording sheet between the two rollers by a so-called friction feed method.

<Problems to be Solved by the Invention> In the above-described conveying device in which the conveying roller and the pinch roller are in pressure contact with each other, when aligning the edges of the recording sheet, or when the conveying roller is provided with a pin, a small hole is formed on the end side. When the opened recording sheet is conveyed by a so-called pin tractor feed method, the pressure contact between the conveying roller and the pinch roller must be released.

Therefore, in the conventional friction feed type sheet conveying device, in order to release the pressure contact between the conveying roller and the pinch roller, it is necessary to provide a special pressure contact releasing member, and further an operating lever and a lever shaft thereof. However, there is a problem that the number of parts increases and the cost also increases.

In particular, when the pinch rollers are provided in a complicated row and the number of pinch rollers is large, the mechanism is inevitably complicated.

The present invention solves the above-mentioned problems of the prior art and provides a sheet conveying device that does not require a special releasing member.

<Means for Solving the Problems> The means of the present invention for solving the above-mentioned conventional problems includes a conveying rotary body that conveys a sheet along a peripheral surface, and a sheet that conveys the sheet along the peripheral surface of the conveying rotary body. A sheet guide member for guiding, a support means for supporting the sheet guide member so as to be movable in the circumferential direction along the peripheral surface of the transport rotating body, a pressing member for pressing the sheet against the transport rotating body, and the sheet. And a release unit for releasing the pressing of the pressing member in conjunction with the movement of the sheet guide member when the guide member moves in the circumferential direction along the peripheral surface of the conveying rotating body. It is characterized by being configured.

<Operation> According to the above-mentioned means, the sheet is conveyed while being guided by the sheet guide by the pressing member when the sheet is conveyed, by the pressing member pressing the conveying rotating body. Further, when it is desired to release the pressing of the conveying rotary member by the pressing member, the pressing can be released by rotating the sheet guide member.

<Example> Next, an example of a sheet conveying apparatus to which the above means is applied will be described.

FIG. 1 is a perspective explanatory view in which a part of the sheet conveying device is removed, and FIG. 2 is a schematic sectional explanatory view.

In the figure, reference numeral 1 is a conveying roller which is a conveying rotary member for conveying the recording sheet 2 along its peripheral surface, and is composed of SBR rubber,
A material having a large friction coefficient, such as CR rubber or NBR rubber, is formed into a cylindrical shape having a length substantially the same as the width of the recording sheet 2, and the central shaft 1a is rotatably supported by the side plate 3 and the shaft 1a It is configured to be driven to rotate in the direction of the arrow a by the motor 4 connected to.

An iron sheet guide member 5 for guiding the recording sheet 2 conveyed by the conveying roller 1 has an R portion 5a along the lower portion of the conveying roller 1, and arms continuously provided at both ends in the longitudinal direction. The portion 5b is the shaft 1 of the conveying roller 1.
It is pivotally attached to a and is rotatably attached to the peripheral surface of the conveying roller 1 at a constant interval by operating a rotating lever 6 provided on one side of the arm portion 5b.

Further, a plurality of openings 7 are bored in the R portion 5a of the sheet guide member 5, and a pinch roller 8 as a pressing member is pressed against the peripheral surface of the conveyance roller 1 through the openings 7 to cause the conveyance roller 1 to move. It is configured to rotate following the rotation.

Further, a comb-tooth-shaped portion 5c in which convex portions and concave portions are alternately formed is formed on one end side of the sheet guide member 5 in the rotation direction, and the exterior 9
It is adapted to mesh with a similar comb tooth-shaped portion 9a formed in the above.

Reference numeral 10 denotes a sheet retainer for preventing the recording sheet 2 conveyed by the conveying roller 1 from floating, which is made of a thin plate of stainless steel or the like, and has one end pressed against the downstream side of the conveying roller 1 in the rotational direction. The other end is fixed to. Reference numeral 12 is an ink jet recording head for recording an image on the recording sheet 2 conveyed by the conveying roller 1 according to a predetermined signal.

Next, each part of the above configuration will be described in more detail.

First, the relationship between the opening 7 and the pinch roller 8 will be described. The opening 7 has a large opening 7 as apparent from FIG.
a and the small opening 7b are formed in a convex shape, and the release portion 7c is formed by the boundary portion between both openings 7a and 7b. On the other hand, the pinch roller 8 has a release cylindrical portion 8b having a diameter smaller than that of the press contact portion 8a formed at both ends of a press contact portion 8a formed of a hard plastic or SBR rubber in a cylindrical shape. Is urged toward the transport roller 1 side by a leaf spring 13 fixed to the substrate 11, and is rotatably held. Further, the longitudinal dimension of the large opening 7a is slightly longer than the longitudinal dimension of the pinch roller 8, and the longitudinal dimension of the small opening 7b is pinch roller 8.
Is slightly longer than the longitudinal dimension of the pressure contact portion 8a.

Next, the release lever 6 will be described. A chevron projection 6a is provided on the outer side of the lever 6, and a V-shaped groove 3 that fits with the projection 6a is formed on the side plate 3 on the side where the projection 6a is provided.
A plurality of a are drilled. Therefore, when the guide sheet member 5 is rotated by the release lever 6, it is possible to rotate the guide sheet member 5 in a stepwise manner by fitting the chevron projection 6a into the V-shaped groove 3a and to fix it.

The relationship between the sheet guide member 5 and the sheet retainer 10 is
When the sheet guide member 5 is rotated in the upstream direction of rotation of the transport roller 1 as shown in FIG. 2, the end portion 5d of the sheet guide member 5 and the sheet presser 10 do not come into contact with each other, and as shown in FIG. When the sheet guide member 5 is rotated in the downstream direction, the end portion 5d contacts the sheet retainer 10 and separates the sheet retainer 10 from the outer peripheral surface of the transport roller 1.

Next, the operation of the sheet conveying device configured as described above will be described.

First, when the recording sheet 2 is conveyed by the cooperative action of the conveying roller 1 and the pinch roller 8, the sheet guide member 5 is rotated in the upstream direction of rotation of the conveying roller 1 as shown in FIG. At this time, the pinch roller 8 moves the sheet guide member 5
Of the conveying roller 1 protruding from the large opening 7a
Press contact with the outer peripheral surface of.

Therefore, when the conveying roller 1 is rotated in the direction of the arrow a while the rollers 1 and 8 are in pressure contact with each other, the pinch roller 7 is driven to rotate, the recording sheet 2 passes between the rollers 1 and 8, and the circumference of the conveying roller 1 is increased. Transported along the surface. At this time, the sheet guide member 5 serves to guide the conveyed recording sheet 2.

Next, when the recording sheets 2 are aligned with each other or conveyed by the pin tractor feed method, the release lever 6 is operated to move the sheet guide member 5 in the downstream direction of rotation of the conveying roller 1 as shown in FIG. Rotate to. When the pinch roller 8 rotates in this way, the releasing cylindrical portion 8b rides on the releasing portion 7c of the sheet guide member 5, and as a result, the pressure contact portion 8a of the pinch roller 8 separates from the outer peripheral surface of the conveying roller 1 and both The pressure contact state of the rollers 1 and 8 is released, and the sheet presser 10 is also separated from the outer peripheral surface of the conveying roller 1.

Therefore, the recording sheet 2 can be fed along the outer peripheral surface of the conveying roller 1 without resistance. At this time as well, the sheet guide member 5 functions to guide the recording sheet 2 being fed.

Even when the sheet guide member 5 is rotated so as to release the pressure contact of the pinch roller 8, the comb tooth-shaped portion 5 between the sheet guide member 5 and the exterior 9 is provided on the entrance side of the recording sheet 2.
c and 9a are in mesh with each other as shown in FIG.
Since there is no gap in the transport path, there is no problem even if the fed recording sheet 2 is fed backward.

As described above, according to this embodiment, the pressure contact of the pinch roller 8 can be easily released by the sheet guide member 5.

In the above-mentioned embodiment, the lever 6 is provided with the chevron projection 6a in order to operate the releasing lever 6 step by step. However, as shown in FIG. It goes without saying that a plurality of V-grooves 6b may be provided, the clip spring 14 may be fixed to the substrate 11, and the clip spring 14 may be provided with a projection 14a that fits into the V-groove 6b.

Further, in the above-described embodiment, the conveying roller 1 is shown as an example of the conveying rotary member and the pinch roller 8 is shown as an example of the pressing member, but the member for conveying the recording sheet 2 is not limited to the roller type. In addition, the present invention can be similarly applied to the case of carrying by a rotating endless belt, and further, the pressing member can be applied even if it is not rotating.

<Effects of the Invention> As described above, the present invention is configured to release the pressing of the conveying rotating body and the pressing member by rotating the sheet guide member, so that the plurality of rows of pinch rollers can be easily released. Unlike the conventional case, it is not necessary to separately provide a member for performing the release, so that the number of parts can be reduced and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective explanatory view of a sheet conveying apparatus showing an embodiment of the present invention, FIGS. 2 and 3 are schematic sectional explanatory views showing a state where a sheet guide member is rotated, and FIG. 4 is another embodiment. FIG. 1 is a conveying roller, 2 is a recording sheet, 3 is a side plate, 4 is a motor, 5 is a sheet guide member, 5a is an R part, 5b is an arm part, 5c is a comb-like part, 5d is an end part, and 6 is for releasing. Lever, 6a is a chevron protrusion, 6b is a V groove, 7 is an opening, 7a is a large opening, 7b is a small opening, 7c is a releasing part, 8 is a pinch roller, 8a is a pressure contact part, and 8b is a releasing cylindrical part. , 9 is an exterior, 9a is a comb tooth-shaped portion, 10 is a sheet pressing member, 11 is a substrate, 12
Is a recording head, and 13 is a leaf spring.

Claims (2)

[Claims] 1. A conveyance rotating body that conveys a sheet along a peripheral surface, a sheet guide member that guides a sheet along the peripheral surface of the conveyance rotating body, and a sheet guide member that surrounds the peripheral surface of the conveyance rotating body. A supporting member that supports the sheet to move in the circumferential direction along the pressing member, a pressing member that presses the sheet against the transport rotating body, and the sheet guide member moves in the circumferential direction along the circumferential surface of the transport rotating body. And a release means for releasing the pressing of the pressing member in conjunction with the movement of the sheet guide member. 2. The sheet conveying apparatus according to claim 1, wherein a plurality of the pressing members are arranged in the circumferential direction of the conveying rotating body.