JPH0342449A - Sheet material feeder - Google Patents

Abstract

PURPOSE:To prevent the hand of a user from being brought into direct contact with sheet material detecting means even when no sheet material is loaded on a loading bed by locating part or all of sheet material detecting means between a pressing means and the loading bed. CONSTITUTION:When sheet materials S are loaded on a loading bed 15, part (detecting lever 21) of a sheet material detecting means is pressed and rotated by sheet materials S, and the existence of sheet materials S on the loading bed 15 is detected. Clearances 26a and 15b not interfering with part 21 of sheet material detecting means 21 and 23 are provided on a pressing means 26 and the loading bed 15. When no sheet material S exists on the loading bed 15, part 21 of sheet material detecting means 21 and 23 can be rotated to the pressing means 26, and the absence of sheet materials S can be detected although part 20 of sheet material detecting means 21 and 23 is located at the position covered by the pressing means 26. Part 21 of sheet material detecting means 21 and 23 can be prevented from being brought into contact with the hand of a user.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a feeding device for an image forming apparatus such as an electrophotographic copying machine or a laser beam printer. The present invention relates to a sheet material detection means for detecting the presence or absence of a sheet material.

(0) Conventional technology Conventionally, image forming apparatuses such as electrophotographic copying machines are equipped with a paper feeder for automatically feeding sheet materials loaded on a loading platform into the apparatus. The paper device is provided with a detection means (hereinafter referred to as a paper-out sensor) for detecting the presence or absence of a sheet material.

An example of a conventional paper feeding device of this kind is shown in FIGS. 7 and 8. FIGS. 7 and 8 show an example of a conventional paper feeding device of this kind, which automatically feeds sheet materials such as envelopes to the laser beam printer 2 using a manual feeding mechanism. A sheet material (envelope) feeding device 1 is shown, and this sheet material feeding bag W1 is detachably attached to a main body 3 of a laser beam printer 2.

A cassette 11 in which normal sheets are stored is installed on the side of the main body 3, and a manual feed port for manually feeding sheets from the sheet material feeding device 1 is provided above the cassette 11 of the main body 3. 3a is formed. The main body 13 of the sheet material feeding device 1 has a loading table 15 on which a plurality of sheet materials S can be stacked, and a feeding roller 25 and a feeding roller 25 in pressure contact therewith are movable up and down in the front part thereof. A weight 26 is provided. On the downstream side of the feeding roller 25, there is a separation plate 32 for separating the sheet material S automatically fed from the sheet material feeding device 1, a conveyance guide 35, 36, and a pair of conveyance rollers 37.
39 etc. are installed. The feeding roller 25 and the pair of conveying rollers 37 and 39 are respectively driven by a drive motor 50 and a gear train 90 shown in FIG.

A paper-out sensor 95 consisting of a detection lever 92 and a photointerrupter 93 pivotally supported by a shaft 91 is disposed on the lower surface side of the loading table 15 . When there is a sheet material S on the loading table 15, the detection lever 92 is rotated to the two-dot chain line position, and when there is no sheet material S, the detection lever 92 is moved to the solid line position due to its own weight or the elasticity of a spring (not shown). rotates to
Its upper end protrudes from a notch 15a formed in the loading table 15.

Now, when a sheet material S such as an envelope is placed on the loading platform 15, it is pressed by the sheet material S and rotates to the position shown by the two-dot chain line in FIG. 7, turning on the photo interrupter 93. The presence of the sheet material S on the stand 15 is detected. The detection lever 92 must be sufficiently rotated to the two-dot chain line position by the strength of the 81 sheet materials (envelopes), so the detection lever 92 should be made as small and lightweight as possible to improve its rotation performance. It is. Therefore, the paperless sensor 95
The structure of the device, including the
Sufficient care must be taken when handling the detection lever 92, which is located in a place that can be directly touched.

(c) Problems to be Solved by the Invention The paperless sensor 95 installed in the conventional sheet material M feeding device is designed so that the detection lever 92 can be directly touched by the user's hand 96 as described above. Because of its location, special care must be taken when handling it, and if the detection lever 92 is touched by mistake, accidents such as malfunction or damage to the device are likely to occur.

Therefore, the present invention provides a sheet material detection means that prevents the user's hand or other member from coming into contact with the detection lever when the sheet material is loaded and fed on the loading platform. It is an object of the present invention to provide a sheet material feeding device that facilitates the loading of sheet materials onto a table.

(d) Means for Solving the Problems The present invention has been made in view of the above-mentioned circumstances. For example, as shown with reference to FIG. A feeding means (25) for feeding the sheet material (S), and a pressing force facing the feeding means (25) for pressing the sheet material (S) against the feeding means (25). a means (26), a sheet material detection means (21, 23) for detecting the presence or absence of the loaded sheet material (S), and a part or all of the sheet material detection means (21, 23) is connected to the pressing means (26) and the loading platform (15>), and an escape for preventing interference with the sheet material detecting means (2i, 23) on both the pressing means (26) and the loading platform (15). (26a, 15b) The sheet material detecting means (21, 23) is partially or entirely covered by the pressing means (26) 2: the loading table (15).

(N) Function Based on the above configuration, the sheet material (S) is placed on the loading platform (15).
When loaded, a part of the sheet material detection means (detection lever 2
1) is pressed by the sheet material (S) and rotates, whereby the presence of the sheet material (S) on the loading platform (15) is detected. Further, by providing reliefs (26a, 15b) in the pressing means (26) and the loading table (15) that do not interfere with a part of the sheet material detecting means (2i, 23), the sheet material detecting means (21, 23) When there is no sheet material (S) on the loading table (15) even though a part of the sheet material is covered by the pressing means (26), the sheet material detection means (21
, 23) can be rotated toward the pressing means (26) to detect the absence of the sheet material (S). As a result, the part (21) of the sheet material detection means (21, 23) is prevented from coming into contact with the user's hand or other members when loading the sheet material (S), and the sheet material detection means (2
1, 23) malfunctions and damage are prevented.

Note that the above-mentioned symbols in parentheses are shown for reference to the drawings, and do not limit the configuration of the present invention in any way.

(F) Example Hereinafter, an example of the present invention will be described with reference to the drawings. Components that are the same as those shown in FIGS. 7 and 8 are designated by the same reference numerals.

1 to 3 each show an example of a sheet material feeding device to which the present invention is applied, with FIG. 1 being a vertical side view that best represents its features, and FIG. 2 being a plan view as well. FIG. 3 each shows a side view in which the drive system is arranged.

In the figure, the sheet material feeding device 1 has a pair of positioning members 10 at its front end (the left end in FIG. 1), and the positioning members 10 are attached to the side of the main body 3 of the laser beam printer 2. The sheet material feeding device 1 can be attached to and removed from the laser beam printer 2 by inserting and removing it into a mounting hole provided on the top surface of the unit. A cassette 11 that is detachably attached to the laser beam printer 2 is disposed below the sheet material feeding device 1, and this cassette 11 is used to stack ordinary sheets. Also,
A manual feed opening 3a for inserting a manual sheet is provided above the cassette 11 on the side surface of the laser beam printer 2.

The main body 13 of the sheet material feeding device 1 has a loading table 15 for loading sheet materials S, and this loading table 15
includes a regulating plate 1 that regulates movement of the sheet material S in the width direction.
6a and 16b are arranged. This regulation plate 16a, 1
A pair of racks 17.19 are slidably disposed below the loading platform 15 in the width direction of the loading platform 15, and the racks 17.19 are rotatably disposed on the back side of the loading platform 15. They mesh with the provided pinions 20, respectively.

As a result, the racks 17 and 19 and the integral regulating plates 16a and 16b are moved in the width direction in conjunction with each other.

On the loading table 15, a detection lever 21 for detecting the presence or absence of the sheet material S is supported by a shaft 22, and its lower end is connected to a photo interrupter 23 provided on the back side of the loading table 15.
Move in and out to turn this on/off. When there is no sheet material S on the stacking platform 15, the upper end portion of the detection lever 21 rotates in a direction that projects toward the upper surface side of the loading platform 15, thereby detecting the absence of the sheet material S. The L arrangement loading table 15 is provided with a relief 15b to avoid interference with the detection lever 21 of the sheet material detection means (21, 23).

On the downstream side of the photo interrupter 23, there is a loading platform 15.
A feeding roller 25 for feeding the sheet material S stacked on the sheet material S from below is rotatably disposed. This feeding port
- A weight (pressing means) 26 is arranged above the roller 25, and the projections formed at both ends of the weight are loosely inserted into a pair of guide grooves 27 (see Fig. 2) provided in the main body 13. By aligning them, they can be moved up and down. This weight 26 is
As will be described later, the sheet material S is pressed against the weight 26. The sheet material S is made of cardboard, such as an envelope, for example. The detection lever 21 of the sheet material detection means (21, 23) is connected to the weight 26
The user's hand 96 (see FIG. 1) and other members are difficult to come into contact with. Further, at the bottom of the weight 26, the sheet material detection means (2
A relief 28a is formed to avoid interference with the detection lever 21 of 1°23). As a result, the detection lever 21 that detects the presence or absence of the sheet material S on the loading table 15 is activated by the weight 2.
Even though it is placed below the weight 26, that is, in a place that is difficult for the user to touch, it can be rotated without interfering with the weight 26 and the loading platform 15.

Attachment member 2 fixedly installed on the downstream side of the weight 26
9 is provided with a tip regulating member 30 for aligning and regulating the leading edge of the sheet material S on the loading table 15, and the lower end thereof and the front end of the loading table 15 are spaced a predetermined distance m apart. The sheet material S is fed and hung from this space Ill. A separation plate 32 made of a high friction material is attached to the mounting base 31 fixed to the lower surface side of the mounting member 29.
(hereinafter referred to as a separation pad) is attached and is inclined at an appropriate angle with respect to the feeding direction of the sheet material S fed from the loading table 15. A flexible elastic member 33 is fixed at a position facing the separation pad 32, and presses the sheet material S fed from the feeding roller 25 against the separation pad 32. This prevents double feeding.

On the downstream side of the separation pad 32, a sheet material S is placed on a guide (
Pair of conveyance guides 35 and 36 and conveyance roller 3
7 are respectively disposed, and a pin roller 39 is biased to press the conveyance roller 37 by a spring (not shown). A microswitch 41 is fixed to a bracket 40 fixed to the upper part of the conveyance guide 35, 36.

Further, a detection lever 42 for detecting the set state of the sheet material feeding device 1 with respect to the laser beam printer 2 is pivotally attached to the bracket 40 via a step screw 43C, and this detection lever 42 has both ends connected to the bracket 40. When the sheet/material feeding device 1 is installed, the detection lever 42 is rotated counterclockwise in FIG. When pressed by the main body 3, the protrusion 4 of the detection lever 42 rotates in the direction shown in FIG.
Each time the microswitch 28 presses the operating lever of the microswitch 41, the microswitch 41 is turned on to detect that the sheet material feeding device 1 is attached.

Next, the drive system in the sheet material feeding device will be explained with reference to FIG.

In the figure, the sheet/material feeding device] has a pair of side plates 46.
47, and guide grooves 27 for guiding the weight 26 floating forward are formed in the open plates 46 and 47, respectively. A substrate 49 is attached to the outer surface of the side plate 46 via a plurality of supports.
This board 49 controls a drive motor 50 fixed to the inner surface of the side plate 46 and sends and receives signals between the laser beam printer 2 and the sheet material feeding device 1. The other side plate 47 has a sheet material feeding device 1.
One end of a cable 5] connecting the main body 3 of the laser beam printer 2 and the main body 3 of the laser beam printer 2 is connected.

A solenoid 53 for controlling a spring clutch, which will be described later, is fixed to a bracket 52 fixed to the side plate 46.
It also serves as a grounding plate for grounding via the metal bearing 56 supporting 7.

As shown in FIG. 3, a relay gear 59 integral with a relay gear 59a is pivotally supported by a shaft 60 on a support plate 57 fixed to the side plate 46 at appropriate intervals. , meshes with a gear 61 fixed to the output shaft 50a of the drive motor 50. Furthermore, the support plate 57
, the relay gears 62 and 63 meshing with the relay gear 59 are shown.
is pivotally supported by a shaft 64, and a relay gear 65 meshing with the relay gear 59a is supported by a shaft 66, respectively.

J-, the support plate 57 is connected to the bracket 52 via the shaft 64.
Therefore, by dropping the bracket 52 to the ground, the shaft 25a of the feeding roller 25 and the shaft 37a of the conveyance roller 37 also fall to the ground.

The relay gear 62 meshing with the relay gear 59 is connected to a gear 63 via a clutch portion 55 having a generally known spring clutch, and the clutch portion 55 is turned on/off by the on/off control of the tolenoid 53. ．． / is turned on to turn on/off transmission of driving force between both gears 62 and 63. The gear 63 meshes with a gear 67 fixed to a shaft 258 that is integral with the feed roller 25 (see FIG. 1). Further, 9, a gear 69 attached to the shaft 37a to which the conveyance roller 37 is fixed is meshed with the relay gear 65. A one-way clutch (not shown) is interposed between the shaft 37a and the gear 69, and when the gear 69 rotates counterclockwise in FIG.
a also rotates in the same direction, and when the gear 69 rotates clockwise, the shaft 37a idles.

A torsion spring 71 is attached to a dowel 70 fixed to the side plate 46, and both ends of the torsion spring 71 are attached to a shaft 3 integrated with a pinch roller 39.
9a and a shaft 66, and the elasticity of this torsion spring 71 causes the pinch roller 39 to move to the conveying roller 37.
It is in pressure contact with the In FIG. 2, reference numeral 72 denotes a connecting member that is electrically connected to the conveying roller 37 via a metal bearing 73 that supports the conveying roller 37, and this connecting member 72 has its base fixed to the side plate 46. Its free end is screwed to the shaft 66 and also serves as a cover for the gear 69.

In the above configuration, the main body 3 of the laser beam printer 2
When the drive motor 50 rotates in response to a paper feed signal from the paper feed signal, the conveyance roller 37 starts rotating via the above-mentioned gear train. Solenoid 5 is activated after a predetermined time T has elapsed since the paper feed signal was generated.
3 is turned on, the feeding roller 25 rotates and starts feeding the sheet material S such as an envelope.

The solenoid 53 is turned off after the predetermined time T2 has elapsed, and the drive transmission to the feeding roller 25 is cut off. At that time,
The rear end of the sheet material S rests on the feeding roller 25, but its leading edge has reached the transport roller 37, so that the sheet material S is fed by the transport roller 37, and the transport roller 37 is one-way. Rotates driven by the action of the clutch. The sheet material S fed from the sheet material feeding device 1 is sent into the main body 3 by a feeding roller 75 of the laser beam printer 2 shown in FIG. Further, the sheet material S fed from the manual feed port 3a of the laser beam printer 2 is detected by the paper detection sensor 76 shown in FIG.
After reaching this point, the paper is sent into the main body 3 of the laser beam printer 2 by the feeding roller 75, where it is printed and then discharged.

Next, the operation of separating and feeding out the sheet material S will be explained with reference to FIGS. 5 and 6.

The sheet material S stacked on the loading platform 15 with its leading edge aligned by abutting the leading end regulating member 30 is brought to its maximum position by the pressing force of the weight 26 and the rotation of the feeding roller 25 in the direction of the arrow. The next sheet materials Sb, Sc, etc. are unwound sequentially from the lower sheet material Sa, and at that time, the next sheet materials Sb, Sc, etc. are dragged by the sheet material Sa due to the frictional force between the sheets, but the leading edge has a high coefficient of friction. Since it is held down by the separation pad 32, only the sheet material Sa that directly receives the feeding force of the feeding roller 25 overcomes the frictional resistance of the separation pad 32 and advances, and as shown in FIG. It is fed beyond the tip 32a.

In the figure, the elastic member 33 is made of a flexible thin plate piece, and its base is fixed to a support plate 77. When the sheet material Sa is fed, the tip of the elastic member 33 bends in the feeding direction as shown in the figure, and the reaction force causes the sheet material Sa, S to bend.
b, Sc, etc. are lifted to the upper separation pad 32 to assist in their separation.

The sheet material Sa beyond the tip 32a of the separation pad 32 is
The same operation is repeated for the zero-order sheet materials Sb and Sc, which are guided by the conveyance guides 35 and 36 and conveyed between the conveyance roller 37 and the pinch roller 39.
The separation and feeding is performed.

In this device, if there is no sheet material S on the loading table 15 and the detection lever 21 is exposed, problems such as malfunction and damage of the paper out sensor (sheet material detection means 21 and 23) may occur as described above. There is a risk that it will happen.

In this regard, the present invention utilizes a weight 26 as shown in FIG.
A detection lever 21, which is a part of the paper-out sensor (21, 23), is disposed below, so that the user can directly touch the detection lever 21 with his or her hand 96 even when the sheet material S is not on the loading table 15. Even if it is possible to touch the detection lever 21, it is configured such that it is only possible to touch the part near the center of rotation.

The closer you get to the tip of the detection lever 21, the more sensitive it becomes to contact, so even if you slightly touch the center of rotation of the detection lever 21, it will not have much of an effect compared to touching the tip. , it is possible to realize the effect of preventing malfunctions, damage, etc. due to contact of the detection lever 21.

(G) As described in detail, according to the present invention, by arranging a part (detection lever) of the paper out sensor (sheet material detection means) below the weight (pressing means), the loading Even when no sheet material is loaded on the table, it becomes difficult for the user's hand to directly touch the sheet material detection means, and there is no need to pay special attention when loading sheet materials on the loading table.
Accidents such as malfunction and damage to the sheet material detection means can be prevented.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional side view of a sheet material feeding device showing an embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a side view showing the drive system, and FIGS. 4 to 6 7 is an operational view, FIG. 7 is a longitudinal side view showing an example of a conventional sheet material feeding device, and FIG.
The figure is also a plan view. 1... Sheet material feeding device 2... Laser beam printer S... Sheet material 15... Loading platform 15b... Escape 21... Detection lever (sheet material detection means) 23... Photo Interrupter (sheet material detection means) 25... Feeding roller (feeding means) 26... Weight (pressing means)
26a...Escape

Claims (1)

[Scope of Claims] 1. A loading table for loading sheet materials, a feeding means for sequentially feeding the sheet materials, and a device facing the feeding means, for feeding the sheet materials to the feeding means. a pressing means for pressing, a sheet material detecting means for detecting the presence or absence of the loaded sheet materials, and a part or all of the sheet material detecting means are located between the pressing means and the loading table, and Both the pressing means and the loading table have a relief for preventing interference with the sheet material detecting means, and part or all of the sheet sensing means is covered by the pressing means and the loading table. A sheet material feeding device characterized by the following.