JPH06160979A - Sheet transporting device and overhead projector using sheet transporting device - Google Patents

Abstract

PURPOSE:To easily move clamped and transported sheet originals on an exposing section and to correct positions by setting the width of a transporting member wider than the width of the sheet original and setting the width of a retaining member narrower than the width of the sheet original. CONSTITUTION:The sizes of the transporting film 2 and the retaining film 3 are such that the film (width 297mm+betamm) broader than the width (width 297mm of A4 size) of the sheet original 1 is used for the width of, for example, the transporting film 2 and the film (width 285+alpha(<297)mm) broader than the width (285mm) of the reading region R of the exposing part and narrower than the width (width 297mm of A4 size) of the sheet original 1 is used for the width of the retaining film 3. Transparent films are used for the transporting film 2 and the retaining film 3. The result is better as the films are thinner if the strength is maintained. Materials having good transmittability of light and stable heat resistance are more preferable as the films and, for example, polyethylene terephthalate films, etc., are used.

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 which can be mounted on an overhead projector (OHP) for placing a sheet original having information such as images and graphs and projecting it on a screen, and particularly to a plurality of sheets The present invention relates to a sheet conveying device that stocks originals on a long conveying member and efficiently conveys them to a projection position.

[0002]

2. Description of the Related Art A sheet conveying device used in an overhead projector (OHP) device proposed by the applicant of the present invention (not known) will now be described. When it abuts against the supply-side roller pair, the document detection sensor detects this and drives the motor that is the drive source of the roller pair.

The common roll on the take-up side is rotated by the rotation of the motor, and the conveying film and the pressing film, which are long transparent films wider than the sheet original, are taken up. As a result, the sheet original is conveyed by the conveying film, the upper surface of the sheet original is pressed by the pressing film, and is wound around the common roll while being sandwiched by the two films.

In this way, after the first sheet original is conveyed, the second and subsequent sheet originals are similarly conveyed and a plurality of sheet originals are wound around the common roll. Then, of a plurality of sheet originals wound on a common roll, an arbitrary sheet original is conveyed to the reading area of the exposure section and irradiated with light, and the transmitted light is projected on the screen through a reflection mirror and a lens. To be done.

[0005]

However, in the conventional sheet conveying apparatus, as shown in FIG. 5, the conveying film 52 and the pressing film 53 have the same width, and the sheet original document has the same width.
Since it is wider than the width of 51, there were the following problems. (1) The exposure area of currently marketed OHP devices is "28
5 mm x 285 mm ", for example, A4
When a sheet manuscript 51 of a size is conveyed with the long side (297 mm) of the sheet manuscript 51 arranged in a direction perpendicular to the conveying direction (hereinafter referred to as "transverse feed"), the image may be missing In such a case, the sheet original 51 sandwiched between the transport film 52 and the pressing film 53 is once taken out, and the center of the sheet original is shifted from the center of the exposure section R so that the necessary position of the sheet original 51 is adjusted so that the required image is not lost. It had to be corrected and re-conveyed, which was troublesome for correction work. (2) Even when the sheet original 51 is skewed on the exposure section R, the sheet original 51 has to be taken out and corrected once as in (1).

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a sheet conveying apparatus which can easily correct the position of a sheet original sandwiched by a conveying member and a pressing member and conveyed on an exposure section. Especially.

[0007]

A typical structure according to the present invention for achieving the above-mentioned object is a long conveying member for conveying a sheet document, and a long member for holding the sheet document. -Shaped pressing member, and a first winding means for winding the conveying member to one side outside the reading area of the exposure unit,
A second winding means for winding the conveying member to the other side outside the reading area of the exposure section; a driving means for driving the first winding means and the second winding means. However, the width of the conveying member is wider than the width of the sheet original, and the width of the pressing member is narrower than that of the sheet original.

[0008]

In the above structure, the width of the conveying member is made wider than the width of the sheet original and the width of the pressing member is made narrower than that of the sheet original, so that the sheet conveyed by being sandwiched by the conveying member and the pressing member is conveyed. The original can be easily moved on the exposure unit to correct the position.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an overhead projector (OHP) sheet conveying device using the present invention will be described with reference to FIGS. 1 is an external view of an OHP device using the sheet carrying device according to the first embodiment, FIG. 2 is a sectional view of the sheet carrying device, and FIG. 3 is an explanatory view of a drive system of the sheet carrying device. 4 is a top view of the exposure unit.

First, the overall structure of the sheet conveying apparatus A and the OHP apparatus according to the present invention will be described. This is to load the sheet conveying apparatus A into the OHP apparatus B shown by the chain double-dashed line in FIG.
The sheet original 1 for OHP used in the apparatus B is automatically sent out. That is, a plurality of sheet originals 1 are sequentially sandwiched between a conveying member 2 made of a long transparent film and a pressing member 3 made of a long transparent film, and both films 2 and 3 are first It is wound around the winding means 4 and the second winding means 5. Then, the two films 2 and 3 are brought into close contact with each other on the exposure section 101 while the sheet original 1 is sandwiched by the stretching means 6. In this state, by driving the right motor 7 as the first driving means or the left motor 8 as the second driving means to wind both films 2 and 3 around the first winding means 4 or the second winding means 5. The desired sheet original 1 is conveyed onto the platen glass 102 of the exposure unit 101 of the OHP device B. The sheet original 1 is irradiated with light from the exposure unit 101, and the transmitted light is transmitted to the arm 1
The image described on the original is enlarged and projected by projecting it on a screen (not shown) through a reflecting mirror 104 and a lens 105 which are projection means supported above by 03.

Next, the structure of each part of the sheet conveying apparatus A will be individually described. (Conveying Film and Pressing Film) The conveying film 2 and the pressing film 3 hold the sheet original 1 so as to sandwich it. The sheet film 1 is placed on the transport film 2, and the sheet document 1 is transported as the transport film 2 is wound. The pressing film 3 presses the upper surface of the sheet original 1 on the transport film 2 to prevent the sheet original 1 from curling and also to prevent the sheet original 1 from being damaged.

The above-mentioned transport film 2 and pressing film 3
4, the width of the carrier film 2 is the width of the sheet original 1 (A4 size width 297 mm).
A wider film (width 297 + βmm) is used, and the width of the pressing film 3 is wider than the width (285 mm) of the reading area R of the exposure unit 101 and the width of the sheet original 1 (A4 size width 297). mm narrower film (width 285
+ Α (<297) mm) is used. A transparent film is used for the transport film 2 and the pressing film 3, and the film is preferably thin as long as the strength is maintained, and a film having a thickness of about 25 μm to 60 μm is preferably used. As a material, a material having good light transmittance and stable heat resistance is preferable, and for example, a polyethylene terephthalate film or the like is preferably used.

Further, as shown in FIG. 4, frame marks 2a are provided at predetermined intervals at the widthwise end of the transport film 2. By detecting the frame mark 2a by a frame detection sensor, a desired document is conveyed and set on the exposure section.

(First Winding Means) The first winding means 4 winds one end of the long conveying film 2 and the pressing film 3 and, as shown in FIG.
Is arranged outside the reading area of the exposure unit 101. In this embodiment, as shown in FIGS. 2 and 3, the conveyor roll 4a is disposed on the right side outside the reading area of the exposure unit 101, and the conveyor film 4 is wound between the front and rear frames 9a and 9b, and the pressing film 3 is pressed. The roll 4b and the roll 4b are rotatably attached.

That is, as shown in FIG. 3, the transport roll 4a
Is a roll shaft 4a1 fixed between the front and rear frames 9a and 9b with screws or the like, and front and rear pulleys 4a2 and 4a3 rotatably mounted on the roll shaft 4a1 are press-fitted to both ends of the transport roll 4a. The transport film 2 is wrapped around the. Similarly, for the press roll 4b, the roll shaft 4b1 is fixed between the front and rear frames 9a, 9b by screws or the like, and the front and rear pulleys 4b2, 4b3 rotatably attached to the roll shaft 4b1 are press-fitted to both ends of the press roll 4b. The pressing film 3 is wound around the pressing roll 4b.

Incidentally, the transport roll 4a and the pressing roll 4
The positional relationship with b is as shown in FIG.
Is on the lower side and the pressing roll 4b is on the upper side.

(Second Winding Means) The second winding means 5 winds the other ends of the long transport film 2 and the pressing film 3, and as shown in FIG.
It is arranged outside the reading area of the exposure unit 101.
In this embodiment, as shown in FIGS. 2 and 3, the exposure unit 101
It is placed on the left side outside the reading area of the front and rear frames 9a, 9b.
A common roll 5a around which the transport film 2 and the pressing film 3 are wound is rotatably attached therebetween.

That is, as shown in FIG. 3, the common roll 5a
Is mounted by pressing the roll shaft 5b between the front and rear frames 9a and 9b with screws or the like, and pressing the front and rear pulleys 5c and 5d rotatably attached to the roll shaft 5b to both ends of the common roll 5a. The transport film 2 and the pressing film 3 are wound around 5a. A gear 5e is engaged with the rear pulley 5d, and the gear 5e meshes with the motor gear 17 to transmit the rotation from the left motor 8. The gear 5e has a built-in torque limiter and is configured so that the transmission of the driving force from the motor gear 17 is not transmitted to the rear pulley 5d at a certain torque or more.

(Tensioning means) In the tensioning means 6, the conveying film 2 and the pressing film 3 sandwiching the sheet original 1 are OHP.
The apparatus B is stretched on the platen glass 102 of the apparatus B so as to be in close contact with each other. In the present embodiment, as shown in FIGS. 2 and 3, the right roller pair is provided on the right side outside the reading area of the exposure unit 101. 6a and 6b are provided, and a left roller 6c is provided on the left side outside the reading area.

The lower right roller 6a and the left roller 6c are
As shown in FIGS. 2 and 3, the roller shafts 6a1 and 6c1 are fixed between the front and rear frames 9a and 9b with screws, and the front and rear pulleys 6a are rotatably attached to the roller shafts 6a1 and 6c1.
2, 6a3 on both ends of the lower right roller 6a, and the front and rear pulleys 6c
It is attached by press-fitting 2, 6c3 to both ends of the left roller 6c. Then, as shown in FIG. 2, the conveying film 2 and the pressing film 3 pass through the upper side of the lower right roller 6a and the lower side of the left roller 6c, so that they are tightly stretched over the exposure section 101. It is like this.

Similarly, the upper right roller 6b is also rotatably attached to the front and rear frames 9a, 9b, and urges the lower right roller 6a by a spring or the like (not shown). By passing the transport film 2 and the pressing film 3 between the right roller pair 6a and 6b, the two films 2 and 3 are brought into close contact with each other.

(Drive System) Next, a drive transmission system for winding the transport film 2 and the pressing film 3 will be described.

The transport film 2 and the pressing film 3
Is configured to wind the transport roll 4a around which they are wound, the pressing roll 4b, and the common roll 5a to the respective rolls by driving rotation. In the present embodiment, the transport rolls 4a and The pressing roll 4b is driven and rotated by the right motor 7 which is a stepping motor, and the common roll 5 constituting the second winding means.
a is configured to be driven and rotated by the left motor 8 which is also a stepping motor. The specific configuration will be described below.

As shown in FIG. 3, a right motor 7 is attached to the right side of the rear frame 9b. In addition, the transport roll 4
The rear pulley 4a3 press-fitted into one end of a is composed of a pulley gear, and the gear portion of the motor pulley gear 10 connected to the right motor 7 meshes with the gear portion of the rear pulley 4a3 to drive the right motor 7. Is transmitted to the transport roll 4a.

On the other hand, a torque limiter 11 is attached to one end of the roll shaft 4b1 of the pressing roll 4b, and a roll gear 12 is attached via the torque limiter 11. The roll gear 12 meshes with a transmission gear 13a. ing.
The transmission gear 13a is a one-way gear attached to a transmission shaft 13b rotatably attached to the rear frame 9b, and the transmission shaft 13b transmits the rotational force in one direction (the pressing roll 4b winds the pressing film 3). Rotation direction), the transmission shaft 13b is locked and the rotational force is transmitted to the roll gear 12. When the transmission shaft 13b rotates in the opposite direction, the transmission shaft 13b is free from the transmission shaft 13b. Therefore, the rotational force is not transmitted to the roll gear 12.

A pulley 13c is connected to the transmission shaft 13b, and the pulley 13c and the pulley portion of the motor pulley gear 10 are connected by a belt 14. As a result, the driving force of the right motor 7 is transmitted to the transmission shaft 13b, and transmitted from the transmission gear 13a to the pressing roll 4b via the roll gear 12 and the torque limiter 11.

As described above, the driving force of the right motor 7 transmits the rotational force to the conveying roll 4a and the pressing roll 4b. At this time, the rotating peripheral speed of the pressing roll 4b becomes faster than the rotating peripheral speed of the conveying roll 4a. The gear ratio is set like this. Incidentally, since the high speed is absorbed by the torque limiter 11 as will be described later, the transport film 2 and the pressing film 3 are always at the same speed with the rolls 4a, 4 respectively.
It is wound around b.

Further, as shown in FIG. 3, a brake plate 15 made of a friction member is pressed against a rear pulley 4b3 press-fitted into the pressing roll 4b by a pressing spring 16,
A brake is applied to the rotation of the press roll 4b.

On the other hand, a left motor 8 is attached to the left side of the rear frame 9b, and a motor gear connected to the motor 8 is attached.
17 is pressed into one end of the common roll 5a, and then the pulley 5d
It meshes with the gear 5e formed in. As a result, the common roll 5a is rotated by the drive of the left motor 8, and the transport film 2 and the pressing film 3 are wound up.

The operation panel 18 of the sheet conveying apparatus A
Is provided with a remote control receiver, and is configured so that the remote controller 19 can remotely operate the drive instructions for the left and right motors 7, 8.

(Sheet Original Supply Structure) As shown in FIG. 2, a supply tray 20a for supplying the sheet original 1 is mounted in the vicinity of the first winding means 4 so as to be swingable around a roll shaft 4a1. And is configured to swing by the drive of the cam 20b. The leading end of the supply tray 20a is located below the upper right roller 6b, and when the tray 20a swings and the leading end moves upward, the sheet original 1 placed on the tray 20a comes into pressure contact with the pressing film 3. Is configured.

A document detecting sensor 20c is provided on the supply tray 20a. This sensor 20c is the tray 20
When the sheet original 1 does not exist on the upper side, the sensor arm stands up. When the sheet original 1 is placed, the sensor arm falls down, and the state of the arm is detected by a reflection sensor or the like not shown to detect the presence or absence of the sheet original 1. It is something to detect.

(Frame Mark Detection Structure) Further, as shown in FIG. 2, a frame detection sensor 21 is provided between the right roller pair 6a, 6b and the transport roll 4a so as to sandwich the transport film 2. This sensor 21 is composed of a transmissive sensor,
The frame mark 2a provided at the widthwise end of the transport film 2 is detected.

The frame mark 2a is the transport film 2
Are continuously provided in the vicinity of both end portions in the lengthwise direction, and are provided at other portions at substantially the same intervals as the length of the sheet original 1. Therefore, when the transport film 2 is wound around the transport roll 4a or the common roll 5a, the position detection of the sheet original 1 can be detected by detecting the frame mark 2a by the frame detection sensor 21, and the continuous frame marks 2a can be detected. As a result, the winding end of the transport film 2 can be detected.

(Sheet Original Conveying Operation) Next, an operation of conveying the sheet original 1 by the sheet conveying device A having the above-mentioned configuration will be described.

First, the sheet original 1 is placed on the supply tray 20a, and its leading end is abutted against the right roller pair 6a, 6b.
The document detection sensor 20c detects this and the left motor 8 is driven. Due to the rotation, the left roller pair 6c, 6d and the common roll 5a rotate in the clockwise direction in FIG. 2, and the transport film 2 and the pressing film 3 are wound up. As a result, the sheet original 1 is conveyed by the conveying film 2 and the upper surface thereof is pressed by the pressing film 3,
The film is wound on a common roll 5a while being sandwiched between the films 2 and 3. At this time, the right roller pair 6a, 6b is rotated by the conveyance of the films 2, 3.

When the films 2 and 3 are wound on the common roller 5a, the transport roll 4a and the pressing roll 4b are driven to rotate so as to feed the transport film 2 and the pressing film 3, respectively, but the right motor 7 is stopped. In addition, due to the stop torque, a rotational load is applied to the transport roll 4a, and the transport film 2 is fed in a tensioned state.

Then, the frame detection sensor 21 is used as the transport film 2
When the frame mark 2a is detected, the driving of the left motor 8 is immediately stopped. Also at this time, since the rotation brake is applied to the transport roll 4a by the stop torque of the right motor 7 described above, the transport film 2 is not fed out by inertia and the film 2 does not sag.

On the other hand, when the pressing roll 4b rotates in the direction in which the pressing film 3 is drawn out, the transmission gear (one-way gear) 13a becomes free, so that the right motor 7
Stop torque does not act on the pressing roll 4b. However, since the brake plate 15 is pressed against the pressing roll 4b, the braking action exerts a load on the rotation of the pressing roll 4b, imparts tension to the pressing film 3 that is fed, and presses it by inertia when the rotation is stopped. The film 3 is prevented from being unrolled to prevent the film 3 from sagging.

After the first sheet original 1 is conveyed as described above, the second and subsequent sheet originals 1 are similarly conveyed, and a plurality of sheet originals are wound around the common roll 5a. When the frame detection sensor 21 detects continuous frame marks 2a during the transportation of the document, the transport film 2 fed from the transport roll 4a is the end, so that the document detection sensor 20c detects the sheet document 1 any more. However, the left motor 8 is not driven.

After winding a plurality of sheet originals 1 on the common roll 5a as described above, to convey an arbitrary sheet original 1 onto the reading area R of the exposure section 101, the remote controller is used.
When the right frame feed button 19 is pressed, the right motor 7 is driven and the transport roll 4a rotates counterclockwise in FIG. 2 to wind up the transport film 2.

When the right motor 7 is driven, the transmission gear 13a
Is locked, the rotational force of the right motor 7 is also transmitted to the pressing roll 4b via the torque limiter 11. At this time, due to the setting of the gear ratio, a rotational force that rotates at a peripheral speed higher than that of the transport roll 4a is transmitted to the pressing roll 4b, but the brake of the common roll 5a that extends the pressing film 3 more than the torque of the torque limiter 11 is applied. If the force is large, the torque limiter 11 will slip. Therefore, the pressing roll 4b is always driven by the rotational peripheral speed of the transport roll 4a, and the pressing film 3 fed out from the common roll 5a is wound by the rotation of the transport roll 4a.

The common roll 5a is driven to rotate as the transport film 2 and the pressing film 3 are fed out.
Since the left motor 8 is in a stopped state, the stop torque exerts a rotational load on the common roll 5a, and the two films 2 and 3 are fed out in a tensioned state.

Then, the frame detection sensor 21 is used as the transport film 2
When the frame mark 2a is detected, the driving of the right motor 7 is immediately stopped. Also at this time, since the rotary brake is applied to the common roll 5a by the stop torque of the left motor 8 described above, the transport film 2 and the pressing film 3 are not fed out by inertia, and the films 2 and 3 are not fed. There is no slack.

When the frame detection sensor 21 detects the frame mark 2a and stops the transport of the transport film 2 as described above, the center of the sheet original 1 in the transport direction is the exposure unit 101 as shown in FIG. The interval between the frame marks 2a is set so as to be located at the center of the reading area R. This is to prevent the OHP device from enlarging the exposed image through the lens so that the periphery of the screen is dark and the image is not clearly projected.

Further, when the right frame feed button of the remote controller 19 is pushed, the next sheet original 1 is similarly conveyed so as to be positioned in the reading area of the exposure section 101. The sheet original 1 that has passed through the exposure unit 101 is sequentially wound around the transport roll 4a together with the transport film 2.

Therefore, the desired sheet original 1 is exposed to the exposure unit 10.
It is possible to easily stop the frame feeding and project the original 1 in a state where the reading area 1 is reached.

The remote control 19 is provided with a right fine feed button and a right continuous feed button. By these operations, the right motor 7 is finely rotated to finely feed the sheet original 1, or the right motor 7 is continuously rotated. It is also possible to continuously convey the sheet originals 1 by doing so. In the case of continuous feeding, when the frame detection sensor 21 detects the continuous frame mark 2a, the driving of the motor is automatically stopped because the transport film 2 is fed to the vicinity of the end.

When the sheet original 1 is wound on the conveying roll 4a as described above and then the sheet original 1 wound on the roll 4a is conveyed again to the reading area R of the exposure section 101, the remote controller 19 is used. When the left frame feed button is pressed, the left motor 8 is driven and the sheet original 1 is conveyed so as to be wound up from the conveyance roll 4a onto the common roll 5a. As a result, the desired sheet original 1 can be conveyed to the reading area of the exposure unit 101. When the sheet original 1 is wound from the transport roll 4a to the common roll 5a, the left fine feed and the continuous left feed can be performed by operating the remote controller 19 in addition to the left frame feed.

According to the above construction, by defining the widths of the conveying film 2 and the pressing film 3 as described above, the sheet original 1 has a portion exposed to the outside of the pressing film 3 on the conveying film 2. The sheet original 1 can be easily moved on the reading area of the exposure unit 101 by operating the above-mentioned operation, and the lines on both sides of the pressing film 3 are projected on the screen to adversely affect the appearance of the projected image. It can also be prevented.

The present embodiment has been described only for the A4 size sheet original 1, but the present invention is not limited to this and can be applied to all size sheet originals.

[0053]

As described above, according to the present invention, the width of the conveying member is wider than the width of the sheet original and the width of the pressing member is narrower than that of the sheet original, so that the conveying member and the pressing member sandwich the sheet and convey the sheet. It is possible to easily move the formed sheet document on the exposure unit to correct the position, and it is possible to project a missing image on the screen. Also,
The skew feeding of the sheet original can be corrected instantly without taking out the sheet original.

[Brief description of drawings]

FIG. 1 is a perspective explanatory view of a sheet conveying device according to a first embodiment of the present invention loaded in an OHP device.

FIG. 2 is a sectional configuration explanatory diagram of a sheet conveying device.

FIG. 3 is an explanatory diagram of a drive system of the sheet conveying device.

FIG. 4 is a top view of an exposure unit.

FIG. 5 is a top view of an exposure unit of a conventional OHP device.

[Explanation of symbols]

 A ... Sheet transport device B ... OHP device 1 ... Sheet original 2 ... Transport film 2a ... Frame mark 3 ... Holding film 4 ... First winding means 4a ... Transport roll 4b ... Holding roll 5 ... Second winding means 5a ... Common Roll 6 ... Stretching means 6a, 6b ... Right roller 6c ... Left roller 7 ... Right motor 8 ... Left motor 9a, 9b ... Frame 11 ... Torque limiter 12 ... Roll gear 13a ... Transmission gear 13b ... Transmission shaft 13c ... Pulley 14 ... Belt 15 ... Brake plate 16 ... Pressing spring 18 ... Operation panel 19 ... Remote control 20a ... Supply tray 20c ... Document detection sensor 21 ... Frame detection sensor 101 ... Exposure section 102 ... Platen glass 103 ... Arm 104 ... Reflecting mirror 105 ... Lens

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiro Matsuo 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (3)

[Claims] 1. A long conveying member for conveying a sheet original, a long pressing member for holding the sheet original, and a winding member for winding the conveying member to one side outside a reading area of an exposure unit. A first winding means for winding, a second winding means for winding the conveying member to the other side outside the reading area of the exposure section, the first winding means, the second winding means And a driving unit for driving, wherein the width of the conveying member is wider than the width of the sheet original and the width of the pressing member is narrower than that of the sheet original. 2. When the width of the sheet original is wider than the width of the exposure portion region, the width of the conveying member is wider than the width of the sheet original,
2. The sheet conveying apparatus according to claim 1, wherein the width of the pressing member is wider than the width of the exposure section region and narrower than the width of the sheet original. 3. An overhead projector comprising: the sheet conveying device according to claim 1; and a projection unit for projecting light emitted from the exposure unit onto a sheet original.