JPH11278710A - Sheet material carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry a sheet with high accuracy using a driving roller and a driven roller, and to efficiently prevent an abrupt change in holding pressure from affecting on the sheet. SOLUTION: A driving roller 96a and a driven roller 96b are provided with rubber rollers 112, 114, respectively. On an outer periphery of the rubber roller 112 (114), a straight portion 116 and a curved portion 118 are formed on each end of the straight portion 116 in a round shape, of which center angle of an arc surface is set at less than 90 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying apparatus having a pair of rollers for pinching and conveying a sheet such as a photographic film or a stimulable phosphor sheet.

[0002]

2. Description of the Related Art For example, stimulable phosphors (stimulable phosphors)
There is known a system that once records radiation image information of a subject such as a human body, reproduces the radiation image information on a photographic photosensitive material such as a photographic film, or outputs a visible image on a CRT or the like. I have.

The stimulable phosphor is composed of radiation (X-ray, α-ray, γ
(Rays, electron beams, ultraviolet rays, etc.), a part of this radiation energy is accumulated, and after irradiation with excitation light such as visible light, a phosphor that emits stimulated emission according to the accumulated energy is referred to. The stimulable phosphor is usually formed in a sheet shape and used as a stimulable phosphor sheet, and the stimulable phosphor sheets are handled one by one in a cassette.

In the above system, for example, a reading section for reading image information recorded on the stimulable phosphor sheet and an erasing section for erasing image information remaining on the stimulable phosphor sheet after reading are provided. An image information reading device is employed. In this image information reading apparatus, a cassette accommodating a stimulable phosphor sheet on which radiation image information of a subject is recorded by an external photographing device is inserted into a loading section. Next, with the cassette opened, the stimulable phosphor sheet is taken out of the cassette under the action of the suction mechanism, and the stimulable phosphor sheet is transported to the reading unit via the sheet transport mechanism. The stimulable phosphor sheet on which the reading section has performed the reading processing of the radiation image information is stored in a cassette disposed in the loading section after the afterimage is deleted in the erasing section.

On the other hand, the above-mentioned system uses an image information reproducing apparatus for recording and reproducing radiation image information on a photographic photosensitive material such as a photographic film. In this image information reproducing apparatus, the photographic photosensitive materials are taken out one by one from a magazine containing a plurality of photographic photosensitive materials under the action of a suction mechanism and transferred to a sheet body transport mechanism. Is transferred to the recording unit via the. In the recording unit, radiation image information obtained from the stimulable phosphor sheet is exposed and recorded by irradiation with laser light or the like.

[0006]

In the above-described image information reading apparatus and image information reproducing apparatus, the stimulable phosphor sheet or the photographic film (hereinafter, referred to as a sheet body) taken out of the cassette or the magazine via the suction mechanism. Is often provided with a pair of rollers that can slide freely with each other.

Normally, this kind of roller pair has a rubber roller (so-called skew-shaped roller) which intermittently forms a conveying surface in the axial direction, and a part of the sheet is held between the rubber rollers. It is configured to be transported. However, when the surface of the sheet body held between the roller pairs is physically or chemically weak, various problems occur.

For example, as shown in FIG.
When the sheet body 4 is nipped and conveyed by the rubber rollers 3a and 3b constituting the above, pressure is applied to the sheet body 4 in the axial direction of the rubber rollers 3a and 3b. Here, the sheet body 4 has a stepped portion of the rubber rollers 3a and 3b,
That is, abrupt changes in the contact pressure occur corresponding to the boundary portions 5a and 5b between the portion to be clamped by the rubber rollers 3a and 3b and the portion to be clamped.

As a result, when a photographic film is used as the sheet member 4, there is a problem that sensitizing lines are generated in the photographic film due to pressure fog. On the other hand, when a stimulable phosphor sheet is used as the sheet member 4, the stimulable phosphor sheet is used many times, so that scratches and stains are caused corresponding to the boundary portions 5a and 5b. Has been pointed out.

The present invention solves this kind of problem, and can effectively reduce the contact pressure of the sheet member at the step portion of the rubber roller for sandwiching the sheet member, and effectively simplify the configuration. It is an object of the present invention to provide a sheet conveying apparatus capable of performing the above operation.

[0011]

A sheet conveying apparatus according to the present invention includes a driving roller and a driven roller for nipping and conveying a sheet, and a rubber roller provided on the driving roller and the driven roller and in sliding contact with each other. Is provided with a straight portion and curved portions formed at both ends of the straight portion. The curved portion has an R shape and the center angle of the arc surface is set to less than 90 °, and is gently inclined from the straight portion toward both ends.

Therefore, the pressure gradient of the contact pressure of the sheet held between the rubber rollers becomes gentle toward both ends of the rubber roller. Therefore, when a photographic film is used as the sheet body, sensitizing muscles due to pressure fogging do not occur, and when the stimulable phosphor sheet is used repeatedly as the sheet body, scratches and No dirt or the like is generated.

Further, since the straight portion is provided on the outer periphery of the rubber roller, the contact area of the sheet member can be more effectively ensured as compared with, for example, a configuration using a crown roller. Can be blocked.

Further, in the sheet conveying apparatus according to the present invention, a ring-shaped groove orbiting around the axis of the rubber roller is provided on both axial end surfaces of rubber rollers provided on the driving roller and the driven roller for conveying the sheet. Are formed to a predetermined depth. Thereby, the elasticity of both ends of the rubber roller becomes smaller than that of the center part side, and the contact pressure at both ends of the rubber roller becomes small.

At this time, the rubber roller is set to have a tapered shape in which the outer peripheral wall surface constituting the ring-shaped groove is inclined toward the axial side toward the inside of both end surfaces. For this reason, the pinching pressure of the sheet body gradually decreases from the center of the rubber roller toward both ends, so that a sudden change in the contact pressure does not occur on the conveying surface of the sheet body. This prevents sensitization from occurring when a photographic film is used as the sheet body, and prevents scratches and stains from occurring when the stimulable phosphor sheet is used as the sheet body. Can be effectively blocked.

[0016]

FIG. 1 is a schematic structural explanatory view of an image information reading apparatus 12 incorporating a sheet conveying apparatus 10 according to a first embodiment of the present invention.

A touch panel 14 having the functions of an operation section and a monitor is provided above the front surface (operation surface) of the image information reading device 12, and a cassette loading section 18 to which a cassette 16 is detachably mounted is provided below the touch panel 14. Can be A sheet unit 20 is formed inside the cassette loading unit 18, and the sheet conveying apparatus 10 according to the first embodiment is mounted near the sheet unit 20. An erasing unit 24 is provided below the sheet conveying device 10 via a conveying system 22.
And a reading unit 26 are provided.

The transport system 22 includes a plurality of pairs of nip rollers 28, and a plurality of erasing light sources 30 constituting the erasing section 24 are arranged on a vertical transport path constituted by the nip rollers 28.

The reading section 26 includes a first and second roller pair 3 for transporting the stimulable phosphor sheet (sheet body) 32 taken out of the cassette 16 in the sub-scanning direction (the direction of arrow A).
An optical system 40 for irradiating the stimulable phosphor sheet 32 conveyed in the sub-scanning direction with a laser beam L in the main scanning direction (a direction substantially orthogonal to the sub-scanning direction); And a light condensing system 42 that photoelectrically reads stimulated emission light generated from the stimulable phosphor sheet 32 by the irradiation of the laser light L.

The cassette 16 includes a stimulable phosphor sheet 32.
And a lid 48 that can open and close an opening 46 of the housing 44.
Opening / closing means (not shown) for opening and closing the lid 48 is provided.

As shown in FIG. 2, the single wafer unit 20 includes suction plates 50a and 50b which can enter the cassette 16 in which the lid 48 is opened by the cassette loading unit 18, and the suction plates 50a and 50b.
a and 50b are set in the cassette 16 and the sheet conveying device 10;
And a moving mechanism 54 capable of feeding the stimulable phosphor sheet 32 in the cassette 16 to the sheet conveying device 10.

In the sheet portion 20, a stimulable phosphor sheet 32 is provided.
The side plates 60a and 60b are provided at predetermined intervals in the direction of arrow C intersecting with the takeout direction (direction of arrow B).
The first motor 6 constituting the moving mechanism 54 is provided on the side plate 60a.
2 is fixed, and the rotation drive shaft 62a of the first motor 62 is
A belt 70 is provided on a small-diameter pulley 64 that is axially mounted on a shaft and a large-diameter pulley 68 that is fixed to one end of a drive shaft 66.

The drive shaft 66 is rotatably supported at both ends by side plates 60a and 60b, and one end of an arm 72 is fixed to a large diameter pulley 68 provided at one end.
One end of a link 74 is swingably connected to the other end of the arm 72, and a first support shaft 76 is connected to the other end of the link 74.
Is provided. One end of an arm 72 is directly fixed to the other end of the drive shaft 66.
A link 74 provided with a support shaft 76 is connected.

As shown in FIG. 3, the side plates 60a and 60b have suction plates 50a and 50b inclined obliquely downward from above with respect to the surface to be sucked (the back surface opposite to the recording surface) of the stimulable phosphor sheet 32. Guide grooves 80 and 82 are provided for moving along a moving locus. The guide grooves 80 and 82 are set to have respective shapes in order to provide a desired trajectory to the suction disks 50a and 50b. 1
The support shaft 76 and the second support shaft 86 are fixed.

On the movable frame 84, suction plates 50a and 50b are mounted corresponding to the size of the stimulable phosphor sheet 32 of the minimum size in the direction of the arrow C. Here, the stimulable phosphor sheets 32 having different dimensions are all, for example,
It is arranged based on a position close to a.

As shown in FIGS. 2 and 3, the sheet conveying apparatus 10 includes a plurality of roller pairs 96, 98 and 10
0, and a second motor 102 for integrally driving the roller pairs 96, 98 and 100. Second motor 1
02 is engaged with a driving pulley 104 connected to the tension roller 108.
a, 108b through each roller pair 96, 98 and 10
0, and is bridged over a driven pulley 110 provided at the center.

As shown in FIG. 2, the roller pair 96 is
Driving roller 96a that is driven to rotate via motor 102
And a driven roller 96b that slidably contacts the driving roller 96a to pinch and convey the stimulable phosphor sheet 32. The driving roller 96a and the driven roller 96b have a predetermined width in the direction of arrow C, and have a plurality of rubber rollers 112 and 114 separated by a predetermined interval.

The rubber rollers 112 and 114 are formed of ethylene propylene rubber (EPDM), and the rubber hardness thereof is set to Hs 70 {± 5}. As shown in FIG. 4, the straight portion 1 having the same diameter D and extending along the axial direction (the direction of the arrow X) is provided on the outer circumference of the rubber roller 112.
16 and both ends of the straight portion 116,
And a curved portion 118 having a shape and a center angle θ of the arc surface set to less than 90 °.

The curved portion 118 is provided integrally at both ends of the straight portion 116 with a radius R from the center 120 of the circular arc surface.
6 is set to be larger than the clearance dimension h in a radially inward direction (arrow Y direction). Specifically, assuming that the axial length of the rubber roller 112 is L, the R-shaped range W of the curved portion 118, the diameter D of the rubber roller 112, the curved portion 118
The radius R of the arc surface and the clearance dimension h of W are: W <L / 3, W <2D, R> D / 10, D / 100 <h
<D / 3 is set. More preferably, D / 10 <W <D / 2, 10 ° <θ <40 °, R> D /
4. The relationship is set as D / 50 <h <D / 10.

The rubber roller 114 is the same as the rubber roller 1 described above.
12, the same components are denoted by the same reference numerals, and a detailed description thereof will be omitted. The other roller pairs 98 and 100 are the same as the roller pair 9 described above.
6 and the detailed description thereof is omitted. In the roller pair 98, a relatively large-diameter roller having a guide function is used.

The sheet conveying apparatus 1 thus configured
The operation of 0 will be described below.

First, the stimulable phosphor sheet 32 on which radiation image information of a subject such as a human body is recorded by a photographing device (not shown) constitutes the image information reading device 12 in a state of being shielded from light in the cassette 16. The cassette is set in the cassette loading unit 18. At this time, the cover 48 of the cassette 16 is swung to a predetermined angular position by an unlocking means (not shown) provided in the cassette loading section 18, and the opening 46 is opened to the sheet 20.

Next, under the driving action of the first motor 62 constituting the moving mechanism 54, the large-diameter pulley 68 rotates integrally with the drive shaft 66 via the small-diameter pulley 64 and the belt 70 in a predetermined direction. One end of an arm 72 is fixed to the other end of the large-diameter pulley 68 and the drive shaft 66, and the arm 72 swings around the drive shaft 66 as a fulcrum.
A first support shaft 76 is connected to the other end of each arm 72 via a link 74, and the first support shaft 76 and the second support shaft 86 are connected to guide grooves 80, 82 of the side plates 60a, 60b.
Are located in

When the arm 72 swings, the first and second support shafts 76 and 86 move along the guide grooves 80 and 82, and the suction plates 50a and 50b
It moves along a locus that inclines obliquely downward from above with respect to the adsorption surface of the stimulable phosphor sheet 32 in the cassette 16 via the movable frame 84 provided with the support shafts 76 and 86 (see FIG. 5).

Therefore, as shown in FIG.
The first motor 62 constituting the moving mechanism 54 is driven in the reverse direction in a state where the surface to be attracted of the stimulable phosphor sheet 32 is sucked by a and 50b. For this reason, under the swinging motion of the arm 72, the suction plate 50 is integrated with the movable frame 84.
a and 50b are the sheet conveying devices 10 from inside the cassette 16;
Then, the stimulable phosphor sheet 32 in the cassette 16 is sucked by the suction disks 50a and 50b and is taken out from the opening 46 of the cassette 16.

Then, the leading end of the stimulable phosphor sheet 32 is sandwiched between a pair of rollers 96 constituting the sheet conveying apparatus 10. At this time, the roller pair 96 is rotating in a direction indicated by an arrow in FIG. 7 at a predetermined rotation speed under the action of the second motor 102 in advance. At about the same time when the leading end of the stimulable phosphor sheet 32 is sandwiched between the roller pair 96, the suction plates 50a, 50b
Is released from the stimulable phosphor sheet 32. As a result, the stimulable phosphor sheet 32 is passed from the roller pair 96 to the transport system 22 via the roller pairs 98 and 100, and once passes through the erasing unit 24 under the action of the transport system 22. And is conveyed to the reading unit 26.

As shown in FIG. 1, in the reading section 26, while the stimulable phosphor sheet 32 is conveyed in the direction of arrow A through the sub-scanning system 38, the laser light L is transmitted from the optical system 40 to the stimulable phosphor sheet 32. The main scanning is performed on the recording surface side of the phosphor sheet 32. Therefore, the radiation image information recorded on the stimulable phosphor sheet 32 is photoelectrically read by the light condensing system 42.

After the reading unit 26 reads the radiation image information, the stimulable phosphor sheet 32 is conveyed in the reverse direction via the conveyance system 22 and is provided in the erasing unit 24 when moving vertically upward. The remaining radiation image information is erased via the plurality of erasing light sources 30. After the stimulable phosphor sheet 32 is further fed into the cassette 16,
The cassette 16 is pulled out from the cassette loading section 18. At this time, since the lid 48 closes toward the housing 44 via lid means (not shown), the cassette 16 is
Is taken out of the image information reading device 12 in a state where the light is shielded.

In this case, in the first embodiment, the roller pair 96 constituting the sheet conveying device 10 is a driving roller 96
a and a driven roller 96b, and rubber rollers 112 and 114 provided on the driving roller 96a and the driven roller 96b have straight portions 1 on their outer circumferences.
16 and a curved portion 118. The center angle θ of the arc surface of the curved portion 118 is set to less than 90 °.

For this reason, the suction cups 5 constituting the sheet unit 20
When the stimulable phosphor sheet 32 sucked and held by the cassettes 0a and 50b and taken out of the cassette 16 is sandwiched between the pair of rollers 96, as shown in FIG.
4 do not contact the stimulable phosphor sheet 32 at both ends. Moreover, the radius R of the arc surface of the curved portion 118 is D /
It is set to 10 or more, more desirably, to D / 4 or more (D is the diameter of the rubber roller 112), and the stimulable phosphor sheet 32 secures a relatively large contact area along the curved portion 118. .

Accordingly, when the stimulable phosphor sheet 32 is sandwiched between the rubber rollers 112 and 114, the rubber rollers 112 and 11 in contact with the stimulable phosphor sheet 32 are used.
At both end portions of No. 4, the pressure gradient of the contact pressure becomes gentle (see FIG. 4). Thereby, in particular, the rubber roller 11
No sudden change in the contact pressure occurs on the stimulable phosphor sheet 32 corresponding to the end portions of the stimulable phosphor sheets 2 and 114, and the stimulable phosphor sheet 32 used repeatedly is damaged or stained. Can be effectively prevented.

Further, the rubber rollers 112 and 114 have
Since the straight portion 116 is provided over a predetermined length, for example, a contact area with the stimulable phosphor sheet 32 can be more effectively secured than that using a crown roller. Therefore, the stimulable phosphor sheet 32
Can be prevented as much as possible. In addition, the rubber rollers 112 and 114 only need to set the shape of the curved portion 118, and there is an advantage that the manufacturing cost is not increased and the cost is extremely economical.

FIG. 9 is a partial perspective view of a roller pair 140 constituting a sheet conveying apparatus 130 according to a second embodiment of the present invention, and FIG. FIG.

The roller pair 140 includes a driving roller 140a and a driven roller 140b.
The driven roller 140b has a plurality of rubber rollers 142 and 144 having a predetermined width in the axial direction and separated by a predetermined interval. Rubber rollers 142, 14
Nos. 4 at both ends in the axial direction.
Ring-shaped grooves 146 and 148 circling around the axis of are formed to a predetermined depth.

The ring-shaped grooves 146 and 148 are formed in such a shape that the opening cross-sectional area decreases inward from both end surfaces of the rubber rollers 142 and 144. Specifically, inner peripheral surfaces 146a, 148a forming the ring-shaped grooves 146, 148
Are inclined inward from the outer peripheral sides of both ends of the rubber rollers 142 and 144 toward the shaft core.

In the roller pair 140 configured as described above, when the stimulable phosphor sheet 32 is sandwiched between the rubber rollers 142 and 144, the fluorescer sheet 32 passes through the ring-shaped grooves 146 and 148 provided at both ends of the rubber rollers 142 and 144. The clamping pressure on both ends of the lever is reduced. Ring groove 1
46 and 148, the rubber roller 14
This is because the elasticity of both end sides of 2, 144 becomes small.

Therefore, the stimulable phosphor sheet 32 includes
Abrupt changes in contact pressure do not occur corresponding to the boundary positions between the portions sandwiched by the rubber rollers 142 and 144 and the portions not sandwiched. Therefore, even if the stimulable phosphor sheet 32 is used repeatedly, the same effects as those of the first embodiment can be obtained, such as generation of scratches and dirt can be reliably prevented.

The ring-shaped grooves 146, 148 are formed by the inclined inner peripheral surfaces 146a, 148a.
2, 144 are set in such a shape that the cross-sectional area of the opening decreases inward from both ends. Thus, the holding pressure of the stimulable phosphor sheet 32 by the rubber rollers 142 and 144 does not suddenly change from the ring-shaped grooves 146 and 148, and the holding pressure of the stimulable phosphor sheet 32 can be gently changed. Will be possible. Therefore, there is an effect that damage to the stimulable phosphor sheet 32 can be more reliably prevented.

In the first and second embodiments, the sheet conveying devices 10 and 130 are provided close to the sheet 20.
30 is a pair of rollers 3 constituting the transport system 22 and the reading unit 26
4, 36. Further, the image information reading device 12 for reading and erasing the stimulable phosphor sheet 32
Alternatively, the same effect can be obtained by incorporating the present invention into an image information reproducing apparatus for recording and reproducing radiation image information on a photographic film.

[0050]

In the sheet conveying apparatus according to the present invention, a straight portion is provided on the outer periphery of the driving roller and the driven roller for nipping and conveying the sheet, and R is provided at both ends of the straight portion.
And a curved portion having a shape and a center angle of the arc surface set to less than 90 °. Therefore, the pinching pressure between the rubber rollers does not suddenly change at both ends of the rubber roller, and the surface of the sheet member is not damaged. In addition, the rubber roller has a straight portion over a predetermined length, and, for example, reduces the conveyance failure of the sheet body at a stroke as compared with the one using a crown roller,
Efficient and high-precision sheet conveying operation can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration explanatory view of an image information reading apparatus incorporating a sheet conveying apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory perspective view of a main part of the sheet conveying apparatus.

FIG. 3 is an explanatory side view of the sheet conveying apparatus.

FIG. 4 is an explanatory diagram of a rubber roller provided in a pair of rollers constituting the sheet conveying apparatus and a distribution of a nipping pressure.

FIG. 5 is an explanatory diagram of an operation when the suction plate constituting the sheet-feeding unit is transferred to the cassette side.

FIG. 6 is an operation explanatory diagram when the suction disk enters the cassette and sucks a stimulable phosphor sheet.

FIG. 7 is an explanatory diagram when the stimulable phosphor sheet is inserted between the pair of rollers.

FIG. 8 is an explanatory front view when the stimulable phosphor sheet is sandwiched between the roller pairs.

FIG. 9 is a partial perspective view illustrating a pair of rollers constituting a second sheet conveying apparatus of the present invention.

FIG. 10 is a partial vertical cross-sectional explanatory view of the roller pair.

FIG. 11 is an explanatory front view of a roller pair according to the related art.

[Explanation of symbols]

10, 130: Sheet transporting device 12: Image information reading device 16: Cassette 18: Cassette loading unit 20: Single sheet unit 22: Transport system 24: Erasing unit 26: Reading unit 50a, 50b: Suction disk 54: Moving mechanism 96 , 98, 100, 140 ... roller pair 96a, 140a ... drive roller 96b, 140b
... follower rollers 62, 102 ... motors 112, 114, 142, 144 ... rubber rollers 116 ... straight parts 118 ... curved parts 146, 148 ... ring-shaped grooves 146a, 148
a ... Inner surface

Claims (5)

[Claims] A driving roller connected to a driving source and rotated; and a driven roller for nipping and conveying a sheet body integrally with the driving roller, wherein the driving roller and the driven roller are A rubber roller is provided to be in sliding contact with the rubber roller. On the outer periphery of the rubber roller, straight portions extending in the axial direction with the same diameter, and formed at both ends of the straight portion, have a round shape, and have a center angle of an arc surface And a curved portion in which is set to less than 90 °. 2. The sheet conveying apparatus according to claim 1, wherein said sheet is a stimulable phosphor sheet or a photographic film. 3. A driving roller connected to a driving source and rotated, and a driven roller for nipping and conveying the sheet body integrally with the driving roller, wherein the driving roller and the driven roller are A sheet conveying device, comprising: a rubber roller that is slidably contacted; and a ring-shaped groove that circulates around an axis of the rubber roller to a predetermined depth is formed on both axial end surfaces of the rubber roller. 4. The sheet conveying apparatus according to claim 3, wherein the rubber roller has a tapered shape in which a wall surface on an outer peripheral side constituting the ring-shaped groove is inclined inward from the both end surfaces toward an axial side. A sheet conveying device, characterized in that: 5. A sheet conveying apparatus according to claim 3, wherein said sheet is a stimulable phosphor sheet or a photographic film.