JPS59207342A - Sheet transfer device - Google Patents

Abstract

PURPOSE:To transfer a sheet always in a fixed direction irrespective of the width of the sheet, by providing a plurality of nip rollers which are urged toward a feed roller by means of springs independent from each other. CONSTITUTION:A sheet is transferred in the direction C to the position of a sensor 12 which therefore, detects the presence of the sheet and delivers a detecton signal to a solenoid section 8. Thereby, a rotary shaft 2 is held at its second rotary position to which it is rotated from its first rotary position, and stays 5a, 5a'... and arm members 3a, 3a'..., respectively provided to retainer members 6a, 6a'..., are released so that the front ends of the arm members and nip rollers 4a, 4b, 4c are urged downward due to spring force and as well their weights. Each nip roller holds the sheet 11 between itself and a feed roller 10. A suitable nip roller to be used is selected in dependence upon the size of a sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conveyance device that conveys sheet materials using nip rollers, and in particular to sheets such as image sheets used for reading and recording images, photosensitive films, and stimulable phosphor sheets. This relates to a device that precisely transports shaped materials.

Conventionally, sheet materials that require particularly accurate maintenance of the conveyance direction (for example, stimulable phosphor sheets used in radiation image information recording/reading devices, image sheets used in image reading/recording devices, recording sheets, etc.) A known conveyance device includes a nip roller that is disposed parallel to the feed roller at a position facing the feed roller (drive roller) and conveys the sheet while nipping the sheet between the feed roller and the feed roller.

Such nip rollers are usually installed on a rotating shaft that is perpendicular to the conveying direction of the sheet and parallel to the sheet via an arm member so as to be parallel to the rotating shaft. There is. In addition, this nip roller is set at a free position so that it is spaced apart from the feed roller when the sheet is not being conveyed, and when the sheet is being conveyed, it is set at a free position so that it can sandwich the sheet between it and the feed roller and convey the sheet. It is set at the nip position and applies surface pressure to the sheet to the extent that the sheet can be conveyed at this nip position at °C.

However, in such a conveying device, if the nip roller is long, the surface pressure applied to the nip roller's 7-tooth during sheet conveyance cannot be uniform at each position in the width direction of the sheet (direction perpendicular to the sheet conveyance direction). If the sheet to be fed is deviated from the center to the left or right, there is a risk that a portion of the two rollers may be lifted off the sheet, that is, it may become uneven. In such a state, the conveyance direction of the sheet becomes oblique, the sheet is conveyed in a meandering manner, and the sheet is no longer conveyed in the desired direction.

This is particularly a problem when the width of the sheet being conveyed is not constant and sometimes changes.

The sheet conveyance device of the present invention has been developed in view of the above circumstances, and an object of the present invention is to provide a sheet conveyance device that can always convey a sheet in a desired fixed direction regardless of the width of the sheet. It is.

The cart conveying device of the present invention includes a plurality of double rollers that are biased in the direction of the feed roller (drive roller) by mutually independent spring members, and the nip roller is positioned at a position in contact with the feed roller and at a position away from the feed roller. It is characterized by comprising a switching means for switching between two positions. These mutually independent springs: w7 have the same spring constant and are set to have the same biasing force.

As described above, according to the device of the present invention, when the nip rollers are not conveyed, that is, at the free position of the nip rollers, the same biasing force is applied in advance to the plurality of nip rollers by the springs having the same spring force. The rate at which the spring force changes between the Since the short nip rollers are in contact with the sheet and do not hit unevenly like when using long nip rollers, the surface pressure on the sheet of each Nisopro is almost uniform at the two-prong position. The sheet can be conveyed in a desired fixed direction without meandering. Further, since a plurality of nip rollers are provided in parallel, even when sheets of different sizes (widths) are fed, it is possible to convey the sheets without always hitting one side.

It is preferable that such a nip roller has at least its peripheral surface made of rubber or the like to prevent damage to the sheet.

Hereinafter, one embodiment of the present invention will be described in detail using the drawings.

FIG. 1 is a plan view showing one embodiment of the apparatus of the present invention. The sheet conveyance device of this embodiment includes a rotating shaft 2 rotatably fitted to side plates 1 and 1 of a conveying section, and three pairs of arm members 3a and 3a' rotatably supported on this rotating shaft 2. ,
3b, 3b'.

3c, 3c', and each pair of arm members 3
a 3 a', 3 b 3 b', 3 c
3 c', the cono arm members 3 a, 3 a'
, 3b, 3b; 3c.

It consists of 3+7=7 rollers 4a, 4b, and 4c, which are rotatably supported by 3c' and provided perpendicular to the sheet conveyance direction (arrow C). Also, this rotating shaft 2 has stays 5a, 5a', 5b, 51), respectively.
', 5C, 5C' three pairs of presser members 6a,
6 a', 61), 51)'.

6c, 6c' are fixedly installed, and three pairs of coil springs 7a,
7a', 7b, 7b', 7C.

7C' is reduced. Coil springs 7a, 7a'.

7b, 7b', 7c, 7c' have the same spring constant. Further, a solenoid section is provided at one end of the rotating shaft 2, and the solenoid section 8 controls the rotation of the rotating shaft, making it possible to switch the position of the nip roller.

Next, the operation of this embodiment will be explained. Figures 2 and 3
The figures are side views showing the nip roller and arm member of FIG. 1 when the sheet is not being conveyed and when the sheet is being conveyed, respectively. When the sheet is not being conveyed, the rotary shaft 2 is also held at the first rotational position by the solenoid section 8.

In this position, each presser member 6a.

Each stay 5a, 5a', jb, 5b' provided at 6a', 6b, 6b', 6c, 6c',
5C, 5c' each arm member 3a, 3
a', 3 b, 31)'.

: The tips of 3c, 3c' are held in an upwardly biased position, thus each two-tube roller 4a.

4, 1), 4. The feed roller ``c'' is held at a free position at a fixed distance upward from the feed roller ``0''.

At this time, each coil spring 7a has already been compressed between the rotating shaft 2 and the vicinity of the tip of the arm portion.

7a', 71), 7b', 7c, and 7c' are the tips of the respective arm portions, ie, the nip rollers 4a, 4b.

It is set to apply an equal downward biasing force to 4C. Note that the foot roller 10 is rotated by a drive shaft, and the nip rollers 4a, 4. b, 4. This is a roller provided opposite to c.

Next, when conveying the sheet, first the sheet is conveyed from the bottom to the top in the direction of arrow C in FIG. send a signal. Thereby, the solenoid section 8 is set to hold the rotating shaft 2 at the second rotational position. That is, the rotation shaft 2 is rotated from the first rotation position (the direction in which the rotation shaft rotates to the left in FIG. 2).
It is held in a second rotational position. As a result, each stay 5a, 5a', 5b,'5 provided on each presser member 6a, 6a', 6b, 6b', 6c, 6c'
b'.

5c, 5c' are each arm member 3a, 3a',
3b.

3k+', 3c, 3c' are released, and the tip of each arm member and the nip rollers 4a, 4b, 4c are connected to each spring 7a, 7a', 7b, 7b', 7c, '7c'.
The nip rollers 4 a , 4 b + 4 c are positioned close to the feed roller 10 to the extent that they can sandwich the sheet 11 between the nip rollers 4 a , 4 b + 4 c, i.e., at two positions. It is set to the knob position. In this way, each nip roller 4a.

4.1) The sheet 11 held between 4C and feed roller 10 is conveyed in direction C by rotation of feed roller 10 and each nip roller 4a, 4b, 4c. In this embodiment, the nip rollers used are differentiated depending on the size of sorting. For example, if the width of a sheet cut into large squares or half is equivalent to the length of arrow A, then the nip rollers 4a and 4c are used to convey these sheets, and the width of the sheet cut into quarters or six is equivalent to the length of arrow B. In this case, nip rollers 4b and 4c are used to convey these sheets. Note that the nip roller that is not in use may be fixed by inserting a stopper or the like so that it does not come into contact with the sheet even when the rotating shaft rotates.

In this way, in this embodiment, the short nip rollers 4a, 4. Two of the nip rollers b and 4c press both ends of the conveyed sheet 11 almost uniformly, and the conveyed sheet is conveyed while being held between it and the feed roller 10. There is no uneven contact with the sheet. Thereby, the sheet can be conveyed in a desired fixed direction, for example, without meandering. In addition, when the sheet is not being conveyed, that is, when the nip roller is in its free position, sufficient spring force is applied to each coil spring having the same spring constant to bias the nip roller downward in advance and to hold the sheet between the feed roller and the nip roller. ing. For this reason, it is possible to use a coil spring with a small spring constant so that the spring force hardly increases due to this degree of displacement during conveyance, that is, even when the nip roller is moved to the nip position. Even when the sheet is moved to a different position, the error in the spring force between the springs relative to the changed position is small, and the surface pressure of the nip roller against the sheet can be made uniform without readjusting the spring force at the two-pronged position of the nip roller.

Furthermore, according to this embodiment, three nip rollers are provided,
Since the nip rollers are used differently depending on the size of the sheet, it is possible to convey sheets of various sizes. The number of nip rollers can be increased depending on the purpose.
Or you can change the interval.

When a sensor (not shown) other than the above-mentioned sensor detects that the sheet conveyance has ended, the detection signal generated by this sensor is sent to the lunoid, and each member returns to the sheet 1 non-conveyed state. is set to

In addition, in the above embodiment, a holding member having a stay is used to hold the arm member, but it is not necessarily limited to such a member. It is also possible to use a combination with a spur gear fixed to the arm member that meshes with the arm member. Alternatively, the rotating shaft can be changed to a fixed shaft, the spur gear fixed to the rotating shaft can be changed to an independently driven spur gear, and the sea 1
A sensor is provided to determine the presence or absence of the sheet and the size of the sheet, and a control section is provided that drives only the spur gear corresponding to the desired two-tipped roller based on the detection signal from the sensor. It is convenient to hold only the nip roller in the free position when the size of the sheet changes successively.

Further, in the above embodiment, the rotation shaft of the nip roller is rotatably supported by the arm member, and the spring member applies a downward force to the arm member.
As shown in the figure, the spring member may directly apply a downward biasing force to the rotating shaft of the nip roller. That is, in FIG. 4, the rotation @9 of the nip roller 4a is fitted into the groove of the arm member 3a so that it can be freely inserted into and removed from the groove.
A downward biasing force is applied to the rotating shaft by the spring member 7a. In this case, the nip roller 4a comes into contact with the sheet on the feed roller 10 when conveying the sheet, and the rotating shaft 9 of the nip roller is directly moved by the spring member 7a at an appropriate position in the groove of the arm member 3a without being influenced by the arm member. Since a biasing force equal to is applied, it is possible to make the surface 1 of the nip roller applied to the sheet even more accurately and uniformly.

[Brief explanation of drawings]

FIG. 1 is a plan view showing one embodiment of the device of the present invention, FIGS. 2 and 3 are partial side views of FIG. 1, and FIG. FIG. 1... Side plate 2... Rotating shaft 3 a +
3 a'+ 31) + 3 b'+ 3 c +
3 c' ... 7 arms 4a, 4b, 4cm = tubular 5a, 5a', 5b, 5b', 5c, 5c'
- Stays 6a, 6a', 6b, 6b', 6c,
6c'-pressing member 7a, 7a', 7J 7b', 7c
, 7c'-coil spring 8, lunoid part 10, feed roller 11, sheet

Claims (1)

[Claims] one feed roller, a plurality of nip rollers provided parallel to the feed roller at intervals, independent of each other, and urged toward the feed roller with equal urging force by elastic side members having the same elastic constant; A sheet conveying device comprising a switching means for switching between a free position where the nip roller is separated from the feed roller and a nip position where the nip roller contacts the feed roller with the biasing force.