JPS5928428Y2 - paper guide device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a paper guide device that guides paper fed from a paper feeder to a pair of registration rollers.

Normally, in an electronic copying machine, the leading edge of the paper fed from the paper feeder comes into contact with the contact point of a pair of registration rollers that are in a stopped state, to correct the skew of the paper and form it on the photosensitive drum. The paper feeding timing is adjusted to match the toner density determined.

Therefore, in order to reliably correct the inclination of the sheet caused by the pair of registration rollers, it is necessary to curve the trailing end of the sheet and use the elasticity, or stiffness, of this curved portion to abut the entire leading end surface against the pair of registration rollers.

However, conventionally, as shown in FIGS. 1 to 3, the paper contact surfaces of the upper and lower paper guide members a and b constituting the paper guide device are formed into mere flat surfaces.

In this case, the paper contact surface of the lower paper guide member is located below the straight line connecting the contact point d between the offer roller C and the paper P and the contact point f between the pair of registration rollers e and e.

In this case, from the paper feed cassette g to the protruding roller C
The paper P sent out through the dowel follows the path shown by the broken line in FIG. As shown in Figures 1 and 3, the curve is meandering.

When such a meandering curvature occurs, the stiffness of the paper P becomes weaker,
This poses a serious problem in that the %i of the paper sheets P is always inconsistent.

The present invention was developed based on the above-mentioned circumstances, and its purpose is to prevent paper from being bent in a meandering manner when it is sent out from a paper feeder and hits a pair of registration rollers, and to ensure that skewed paper is properly aligned. Therefore, it is an object of the present invention to provide a paper guiding device that can perform the following operations.

Hereinafter, one embodiment of the present invention will be described based on FIG. 4.

In the figure, 1 is a paper guide device for guiding the paper P sent out from the paper feeder 2 to a pair of registration rollers 3, 3. This paper guide device 1 is arranged to form a paper path 4 between mutually facing surfaces. It is composed of upper and lower paper guide members 5 and 6.

Paper contact surfaces 5a and 6a of these paper guide members 5 and 6 have a curved shape.

The degree of curvature of the paper contact surface 6a of the lower paper guide member 6 is determined at least at the contact point 01 between the protruding roller γ of the paper feeder 2 and the paper P in the paper feed cassette 8, and the contact point 01 between the registration roller pair 3, 3. It is curved so as to protrude above the straight line connecting it to point 02.

Further, the upper paper guide member 5 is arranged at a certain angle with respect to the lower paper guide member 6 so that the paper path 4 is wide on the paper feeder 2 side and narrows on the registration roller pair 3 side. ing.

Then, in order to keep the paper P in contact with the pair of registration rollers 3, 3, the leading edge side of the paper P is supported, and the paper P
The rear end side of the sheet P can be curved so that the leading end of the sheet P can be brought into elastic pressure contact with the pair of registration rollers 3, 3.

In addition, on the paper feeder 2 side of the paper contact surface 5a of the upper paper guide member 50, there is a curved portion at the rear end of the paper P that deforms and protrudes in the direction of the top of the take-out roller 7 (in the direction of arrow A) and curves in a meandering shape. It is designed to prevent

Furthermore, a contact prevention member 9 is provided between the upper paper guide member 5 and the take-out roller 7 to prevent the sent-out paper P from coming into contact with the take-out roller 1 if the feeding state of the paper P changes for some reason. is provided.

Thus, the paper P sent out from the paper feed cassette 8 via the take-out roller 7 is guided along the paper contact surface 6a of the lower paper guide member 60, that is, in the state shown by the broken line, and the leading edge of the paper P is brought into the stop device. a state in which it hits the pair of registration rollers 3, 3 located at the same time as the paper contacting surface 5a of the upper paper guide member 5;
That is, it curves to the state shown by the solid line.

Then, elastically pressing the leading edge of the paper P corrects the inclination of the paper P.

At this time, the take-out roller 7 is stopped and the feeding of the paper P is temporarily stopped to prevent the paper P from becoming meandering.

Next, the pair of registration rollers 3, 3 and the take-out roller 7 are driven in synchronization with the operation of forming a toner image on the photosensitive drum.
This means that the paper P is fed without being tilted.

Furthermore, even if the feeding state changes for some reason, the contact prevention member 9 disposed near the take-out roller 7 prevents the paper P from being deformed as shown by the dashed line and coming into contact with the take-out roller 7. It can maintain a curved state.

In addition, as shown in FIG. 5, when employed in a double cassette type copying machine, etc., a lower paper guide member 6 corresponding to the upper paper feed cassette 8 and an upper paper guide member corresponding to the lower paper feed cassette 8 are provided. 5 may be constructed from a common member 10.

Note that 11 is a photosensitive drum.

In the description of the other embodiment (FIG. 5), the same parts as those of the embodiment (FIG. 4) are given the same reference numerals and the explanation thereof will be omitted.

As explained above, the present invention is directed to a paper fed from a paper feeder that is guided to a pair of registration rollers, and the present invention is directed to a contact point between a take-out roller and a paper in the paper feeder and a pair of registration rollers. A lower paper guide member having a paper contact surface curved so as to protrude upward from a straight line connecting the contact point, and a lower paper guide member provided opposite to the lower paper guide member so that the leading edge of the paper is in contact with a pair of registration rollers. an upper paper guide member having a curved paper contact surface that supports the paper so that only the rear end side of the paper is curved so that the leading edge of the paper comes into elastic pressure contact;
The paper guide device is characterized by comprising a contact prevention member provided between the upper paper guide member and the take-out roller to prevent abnormally fed paper from coming into contact with the take-out roller.

Therefore, by simply changing the shape of the paper guide member, it is possible to reliably prevent the meandering curvature of the paper fed from the paper feeder and hit the pair of registration rollers, and to reliably correct the inclination of the paper.

Further, even if the feeding state changes for some reason, the contact prevention member disposed near the take-out roller prevents the sheet from coming into contact with the take-out roller and maintains a normal curved state.

[Brief explanation of drawings]

Figures 1 to 3 are vertical sectional front views schematically showing the paper guiding state in a conventional device, Figure 4 is a vertical sectional front view schematically showing an embodiment of the present invention, and Figure 5 is a double cassette type. FIG. 7 is a front view of an address schematically showing another embodiment when adopted in a copying machine. P...Paper, 1...Paper guide device, 2.
... Paper feeding device, 5 ... Upper paper guide member, 6
...Lower paper guide member, 7...Take-out roller, 9...Contact prevention member, 01...Contact point, 02... Contact point, L... straight line,
5a...Paper contact surface, 6a...Paper contact surface.

Claims (1)

[Scope of utility model registration request] Press the button on the device that guides the paper sent out from the paper feeder to the pair of registration rollers, and press the button above the straight line connecting the point of contact between the extension roller and the paper in the paper feeder and the point of contact between the pair of registration rollers. A lower paper guide member having a curved paper contact surface protruding from the lower paper guide member, and a state in which the leading edge of the paper is in contact with a pair of registration rollers provided opposite to the lower paper guiding member, and the leading edge of the paper is elastically pressed against the pair of registration rollers. An upper paper guide member having a curved paper contact direction that supports the paper so that only the trailing edge of the paper is curved, and an offer roller that is provided between the upper paper guide member and the offer roller to serve as a guide for abnormally fed paper. A paper guide device comprising a contact prevention member that prevents contact with a roller.