JPH107285A - Document feeding device for overhead projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent floating of a heat end part of a document on a stage and to eliminate a projected part by a document tray, etc., above the stage. SOLUTION: This device is constituted to be arranged on a side of a stage 54 provided on an upper part of an OHP main body, to supply one piece each of documents P on to the stage 54 at the time of projection and to discharge the documents P after projection. In this case, a head end part of the document P standing by on a document tray 11 is held by a separation roller 12 and a separation plate 13 at a position lower than an extension of the stage 54, and after the document P is transported in a direction of a feeding roller 14 by rotating the separation roller 12, the copy P is supplied on to the stage 54 by rotating the feeding roller 12. Thereafter, a protruded deflection is made between both of the rollers 12, 14 by increasing feeding length of the copy per unit time by the separation roller 12 longer than feeding length of the copy per unit time by the feeding roller 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an OHP document feeder which feeds a plurality of waiting documents one by one and supplies the documents to a stage of an overhead projector (hereinafter simply referred to as OHP) main body.

[0002]

2. Description of the Related Art FIG. 6 shows an example of the prior art of this type of document feeder. In the figure, a document feeder 10 ′ accommodates a plurality of documents P in a standby state,
A document tray 11 having a leading end urged from below by a spring, a separating roller 12 disposed in front of the leading end of the document tray 11, and a spring for holding the document P between the separating roller 12 and the lower side. Plate 13 urged by
And a feed roller 14 disposed in front of them, an auxiliary roller 15 in contact with the lower surface thereof, a guide plate 16 for discharging a document, and a discharge roller 17 disposed at the end thereof.
And a document receiver 18 located behind the discharge roller 17 and above the document tray 11.

[0003] Reference numerals 11a, 16a, and 18a denote rotating shafts of the respective members. Each of the members 11, 16, and 18 is rotatable in the direction of an arrow. Furthermore, each roller 12, 14,
17 are rotatable in the directions of the arrows.

[0004] On the other hand, reference numeral 50 denotes an OHP main body, which includes a light source 52 and a Fresnel lens 5 housed inside a casing 51.
3, a stage 54 on the upper surface of the casing 51, and a projection lens 55 and a projection mirror 56 disposed above the stage 54. Here, the feed roller 14 and the auxiliary roller 15 are arranged at one end of the stage 54.

The operation of this prior art is briefly described. When the separating roller 12 is rotated while the free end of the document tray 11 is located on the separating roller 12 side as shown in FIG. By the cooperative action, the leading end of the first document P is held between the separating roller 12 and the separating plate 13, and the document P is sent forward. At the same time, the feed roller 14 also starts to rotate clockwise.

The leading edge of the original P sent forward is held between the feed roller 14 and the auxiliary roller 15 while pushing the guide plate 16 upward, and is conveyed toward the stage 54 as it is. Here, the document P is positioned below the guide plate 16.
When the trailing edge of the feed roller 14 passes, the guide plate 16 rotates and returns, so that the movement of the guide plate 16 is detected by a photo interrupter (not shown) or the like to detect the document length, and the rotation period of the feed roller 14 is detected. Is controlled, the projection portion in the document P can be positioned on the stage 54 with the rear end of the document P held.

When the projection of the document P is completed, the feed roller 14 is rotated in the reverse direction to reverse the document P, and the document P is discharged from the guide plate 16 via the discharge roller 17 onto the document receiver 18. Good.

[0008]

In the case of the OHP, if the document P rises above the stage 54, the projected image is out of focus. Therefore, as shown in FIG. In general, a mechanism for transporting the stage 54 in parallel with the stage 54 is used. Here, in order to realize a high-performance separating mechanism for securely transporting the documents P on the document tray 11 one by one, the document tray 11 with respect to the separating plate 13 is required.
It is known from experience that it is preferable to set the inclination angle to about 30 degrees. For this reason, when the separating plate 13 is disposed on an extension of the stage 54 as shown in FIG. 6, when viewed from the side, the upper end of the document tray 11 (near the rotation shaft 11a) and the rear of the document receiver 18 The end travels considerably higher than the surface of the stage 54, and there are inconveniences such as blocking a part of the light projected on the screen and hindering the speaker from seeing the projected image on the screen.

In order to avoid such inconveniences, as shown in FIG. 7, the members behind the feed roller 14 are simply slightly tilted downward as a whole, so that the stage 54
Some measures have been taken to reduce the projecting portion of the document tray 11 and the like upward. However, in this case, as shown in the figure, the leading end of the document P is easily lifted from the surface of the stage 54, and the focus is not adjusted. In particular, when the method of gradually projecting from the leading end of the document P is adopted to enhance the presentation effect, the above-described floating of the document P is a fatal defect.

Therefore, as shown in FIGS. 8 and 9, a structure for eliminating the protrusion of the document tray 11 and the like and preventing the document P from floating is proposed. That is, each of them basically employs the inclined structure as shown in FIG. 7 to eliminate the protrusion of the document tray 11 and the like, and in the document feeder of FIG. The document P is expanded and pressed against the leading end of the document P. Further, in the document feeder shown in FIG. 9, the document P is prevented from being lifted by pressing the whole area of the document P in the width direction by the wide feed roller 14B.

However, according to these structures, there has been a problem that the increase in the number of parts and the size of the feed roller lead to an increase in the manufacturing cost and an increase in the size and weight of the entire apparatus. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an OHP document feeder capable of eliminating protrusions of a document tray or the like without causing these inconveniences and reliably preventing the document from floating.

[0012]

In order to solve the above-mentioned problems, the invention described in claim 1 is arranged on a side of a stage provided on an upper part of an OHP body, and originals are projected one by one at the time of projection. An OHP document feeder for feeding a document onto a stage and discharging a document on the stage after projection, wherein the leading end of the document waiting on a document tray is separated at a position below an extension of the stage. OHP which feeds the original to the stage by rotating the feed roller and feeding the original to the stage after rotating the separating roller to convey the original in the direction of the feed roller disposed between the separating roller and the stage. Document feeder, wherein the feed length of the document per unit time by the separating roller is longer than the feed length of the document per unit time by the feed roller. A. As a result, the document can be bent in a convex shape between the feed roller and the separating roller, and a force toward the surface of the stage is applied to the leading end of the document to prevent the document from floating.

According to a second aspect of the present invention, the rotation axis of the auxiliary roller disposed below the feed roller and pressed against the back surface of the document is positioned closer to the separating roller than the rotation axis of the feed roller. Thus, a force toward the surface of the stage can be made to act more strongly on the leading end of the document.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a main part showing an embodiment of the present invention, and the same components as those in FIG. 7 are denoted by the same reference numerals. Since the main part of this embodiment is the same as that of FIG. 7, there is a part that overlaps with the above description, but the configuration of the embodiment will be described for understanding the present invention.

In FIG. 1, a document feeder 10 includes a document tray 11 in which a plurality of documents P in a standby state are stored, and a leading end of the document tray 11 is urged from below by a spring 19; Separating roller 12 arranged in front
And a separating plate 13 urged from below by a spring 20 to hold the original P between the separating roller 12 and the separating roller 12 and a feed roller 14 disposed in front of the separating plate 13. A contacting auxiliary roller 15, a document discharge guide plate 16, a discharge roller 17 disposed at the end thereof, and a document positioned behind the discharge roller 17 and disposed above the document tray 11. And a receiver 18.

Reference numerals 11a, 16a, and 18a denote rotating shafts of the document tray 11, the guide plate 16, and the document receiver 18, respectively. Each of the members 11, 16, and 18 is rotatable in the direction of an arrow. The separation roller 12 and the feed roller 14 rotate in the direction of the arrow in FIG.
Rotates in the direction opposite to the arrow, and the discharge roller 17 can rotate in the direction of the dashed arrow.

In this embodiment, the feed roller 14
Therefore, the feeding length of the document P per unit time by the separation roller 12 is longer than the feeding length of the document P per unit time by. Specifically, both rollers 1
The rotation speed of the separation roller 12 is changed by changing the reduction ratio of the gear between the drive source and the drive source.
The rotation speed is set to be about 20% faster than the rotation speed. As another method, the rotation speeds of both rollers 12 and 14 are made equal, and the outer diameter of the separation roller 12 is
It may be larger than 4.

FIG. 4 shows the document tray 11 and the separating plate 1.
3 schematically shows the intersection angle of the stage 3 and the stage 54. In FIG. 4, the document tray 11 and the separating plate 13 intersect at about 30 degrees (α ≒ 30 degrees) in order to realize a suitable separating mechanism as in the prior art.
Is an angle β (β <α) with respect to the stage 54.
Intersect at

The separating plate 13 is an extension line 5 of the stage 54.
4a, and the position where the document P is held by the separation roller 12 and the separation plate 13 is below the extension line 54a. Therefore, the document tray 11 and the document receiver 18 are positioned above the stage 54. No longer protrude significantly. Of course, if the angle α is further reduced and the angle β is further increased, the document tray 11 and the document receiver 18 can be positioned further below.

FIG. 5 is an enlarged side view of the feed roller 14 and the auxiliary roller 15. In this embodiment, the rotation axis of the auxiliary roller 15 is slightly behind the rotation axis of the feed roller 14 by a distance ΔL. (Toward the roller 12).

Next, the operation of this embodiment will be described with reference to FIGS. FIG. 1 shows an original state in which the document P is sent out onto the stage 54. Handling roller 12
The document P sent forward through the path is passed under the guide plate 16, held between the feed roller 14 and the auxiliary roller 15, and sent toward the stage 54. At this time, the feed length of the document P by the separation roller 12 is
, The leading end of the document P is
4, the brake is applied, and the portion slightly behind the tip bends upwards as shown in FIG.
The guide plate 16 is pressed by the lower surface.

As a result, a force is applied to the leading end of the document P that has reached the stage 54 so as to be pressed against the stage 54. The leading end of the document P on the left side of the feed roller 14 has a small weight at the beginning of feeding, but the document P is conveyed forward so as to be in close contact with the stage 54 due to the pressing force of the bending portion by the guide plate 16 described above. To go. In particular, by arranging the rotation axis of the feed roller 14 slightly ahead of the rotation axis of the auxiliary roller 15 as shown in FIG.
Surface). At the same time, it is also effective to prevent the original P from bending in the reverse direction between the feed roller 14 and the separating roller 12.

FIG. 2 shows a state in which the document P is further fed, and the weight of the document P on the stage 54 is greater than that in FIG. 1, so that the adhesion between the document P and the stage 54 is further improved.

FIG. 3 shows a state in which the document P has been further fed than in FIG. The separating roller 12 is rotatable in only one direction by an internal one-way clutch mechanism, and after the original P is sent out to a certain length, the driving force is cut off, and the separating roller 12 is rotated by the frictional force of the advancing original P. It is configured to be. At this time, the separating roller 12
Since the document P does not rotate positively, the document P is not bent between the feed roller 14 and the separation roller 12, but at this time, the document sent on the stage 54 is long and its own weight is large. Therefore, there is no longer a possibility that the document P will rise.

Although not shown, the document P after projection is guided onto the guide plate 16 by the reverse rotation of the feed roller 14 as in the prior art, and is discharged onto the document receiver 18 by the rotation of the discharge roller 17. . At this time, the rear end of the document P easily moves diagonally upward along the guide plate 16 due to the shift of the rotation axis between the feed roller 14 and the auxiliary roller 15 described above. And smooth discharge is promoted.

[0026]

As described above, according to the first aspect of the present invention, the original can be bent in a convex shape between the separation roller and the feed roller and fed in the direction of the stage. A force can be applied to the leading end of the document along the surface of the stage without using the feed roller. Accordingly, even when the inclination structure of the document tray and the separating mechanism (the separating roller, the separating plate, etc.) for reducing the protruding portion of the document tray or the like above the stage is adopted,
Defocusing of the projected image can be eliminated without the leading end of the document rising from the stage. At the same time, the document tray and the separating mechanism are inclined at a predetermined angle with respect to the extension of the stage to reduce the protruding portion above the stage, and prevent this protruding portion from obstructing the projection light and the speaker's view. be able to.

[Brief description of the drawings]

FIG. 1 is a side view of a main part showing an embodiment of the present invention.

FIG. 2 is a side view of a main part showing the embodiment of the present invention.

FIG. 3 is a side view of a main part showing the embodiment of the present invention.

FIG. 4 is a schematic explanatory view of a main part in FIG. 1;

FIG. 5 is an enlarged view of a main part in FIG. 1;

FIG. 6 is a side view showing a main part of the related art.

FIG. 7 is a side view showing a main part of the related art.

FIG. 8 is a side view showing a main part of the related art.

FIG. 9 is a plan view showing a main part of a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Document feeder 11 Document tray 11a, 16a, 18a Rotating shaft 12 Release roller 13 Release plate 13a, 54a Extension 14 Feed roller 15 Auxiliary roller 16 Guide plate 17 Discharge roller 18 Document receiver 19, 20 Spring 50 OHP body 51 Casing 52 light source 53 Fresnel lens 54 stage 55 projection lens 56 projection mirror P original ΔL distance

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Akio Ishii 108 Sayamagahara, Iruma-shi, Saitama Plus Co., Ltd.

Claims (2)

[Claims] 1. An overhead projector which is disposed on a side of a stage provided on an upper part of an overhead projector main body and supplies originals one by one onto the stage at the time of projection and discharges the originals on the stage after projection. A document feeder, wherein a leading end of a document waiting on a document tray is held by a separating roller and a separating plate at a position below an extension of the stage, and the separating roller and the stage are rotated by rotating the separating roller. And a document feeder for an overhead projector that feeds a document on a stage by rotating the feed roller after transporting the document in the direction of a feed roller disposed between the document feeder and the document feeder. The length is set to be longer than the length of the original fed by the feed roller per unit time. Document feeder for an overhead projector to. 2. The document feeder for an overhead projector according to claim 1, wherein a rotation axis of an auxiliary roller disposed below the feed roller and pressed against a back surface of the document is a separation roller more than a rotation axis of the feed roller. A document feeder for an overhead projector, wherein the document feeder is located on a side of the document.