JP3194440B2 - Paper feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding apparatus provided with a paper feeding cassette detachably mountable to an apparatus main body, and a semicircular paper feeding roller partially formed with a cutout surface.

[0002]

2. Description of the Related Art In a paper feeder for feeding recording paper to an image forming apparatus such as a copying machine, the recording paper is stored in a paper feed cassette detachable from a main body of the apparatus, and fed by a separate paper feed mechanism. The paper is fed separately from the cassette. The recording paper separated and fed is conveyed in the conveyance path by a conveyance roller pair arranged in the apparatus main body, and further, after being aligned by the registration roller pair, is conveyed to the image forming section of the image forming apparatus at a predetermined timing. Be started.

Some of the separation paper feed mechanisms include a paper feed roller that comes in contact with and separates from recording paper in a paper feed cassette at a predetermined timing during rotation.

FIG. 8 is a front view showing an example of a paper feed roller and a rotary shaft in a conventional paper feed device, and FIG. 9 is a side view of the paper feed roller shown in FIG.

The paper feed roller 30 is mounted on a rotating shaft 1 which is rotated by a drive mechanism (not shown), and has a core portion 31 having a cutout surface 31a parallel to the chord direction, and an outer periphery of the core portion 31. It is composed of a rubber cover 32 and the like attached to a circumferential portion on the surface.

A through hole 31b into which the rotating shaft 1 penetrates is formed in the core portion 31, and a female screw hole 31c into which the screw 33 is screwed is formed in the cut surface 31a.

The screw 33 presses the tip of the rotating shaft 1 penetrating the through-hole 31b into pressure so that the feeding roller 30
Is fixed to the rotating shaft 1.

[0008]

In the paper feeding apparatus having the above-described structure, when the paper feeding cassette is pulled out of the apparatus body during non-operation, the paper feeding roller 30 is prevented from interfering with the paper feeding cassette. The paper feed roller 30 is held at an initial position where the notched surface 31a is substantially parallel to the recording paper.

However, if the paper feed roller 30 is not held at the initial position due to a power failure or the like and the paper feed cassette is pulled out of the apparatus main body, the paper feed roller 30 comes into contact with the paper feed cassette and cannot be pulled out. It may be.

Further, when the recording paper is conveyed and slidably contacts a conveyance path or a conveyance roller, the paper feed cassette is frictionally charged, so that a spark may be generated from the paper feed cassette to the apparatus main body. The occurrence causes a malfunction of the device.

Further, since the paper feed roller 30 is fixed to the rotary shaft 1 penetrating the through hole 31b by a screw 33, for example, the paper feed roller 30 can be replaced by a screwdriver or other tool. Loosen 33 and rotate 1
Must be removed from the main body of the apparatus, and the steps must be performed in reverse order during assembly. As described above, since the assembling work and the removing work of the sheet feeding roller 30 have many steps, it takes a long time and is a complicated work.

Further, as described above, the feed roller 30 is rotated by the rotating shaft 1 so as to be held at the initial position when the apparatus is not operated.
It is necessary to fix the position in the rotation direction before fixing with the screw 33.

An object of the present invention is to provide a sheet feeding device capable of easily replacing and assembling a sheet feeding roller with respect to an apparatus main body.

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention has a semicircular shape with a partially cutout surface, and is provided on a rotating shaft to separate and feed a sheet. In a paper feed device having a paper feed roller that comes in contact with and separates from a recording paper at a timing, two insertion pins having different lengths are implanted on the rotation shaft, and An outer fitting groove which is opened on the outer peripheral surface for external fitting so that
Two fitting grooves corresponding to the length of the fitting pins into which the two fitting pins having the different lengths are removably fitted are formed in the outer fitting grooves in order to fix the sheet feeding roller in the rotation direction. Further, in order to fix the paper feed roller in the axial direction of the rotation shaft, a fixing ring abutting on the side surface of the paper feed roller is detachably fitted to the rotation shaft so that the cutout surface is at a predetermined position. Wherein the semicircular feed roller is disposed on the rotating shaft. Further, in order to prevent the paper feed roller disposed on the rotation shaft from tilting, an inclination preventing member is provided on the paper feed roller so as to be in close contact with the rotation shaft.

[0015]

According to the above-mentioned means, the outer fitting groove of the paper feed roller, two fitting pins of different lengths implanted on the rotating shaft, and the fitting pin formed in the outer fitting groove have the same length. With the corresponding two fitting grooves and the fixing ring fitted to the rotating shaft and abutting against the side surface of the feeding roller, the feeding roller can be easily detached from the rotating shaft, and Since the fitting groove corresponds to the length of the fitting pin, the positional relationship between the rotating shaft in the rotating direction and the cut surface of the sheet feed roller can be always fixed. Furthermore, by the inclination prevention member which comes into close contact with the rotating shaft provided in the paper feed roller,
It is possible to prevent the sheet feeding roller from being inclined with respect to the rotation axis.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

In the following drawings, members described with reference to FIGS. 8 and 9 are denoted by the same reference numerals, and description thereof is omitted.

FIG. 1 is a side sectional view showing the structure of a main part in one embodiment of the present invention.

FIG. 1 shows a state in which the sheet cassette 10 is mounted at a mounting position in the apparatus main body.

The paper feed cassette 10 stores the recording paper P in a case portion 11, and urges the recording paper P upward by an urging plate 12 supported by a bottom plate 11a.

When the paper cassette 10 is set at the mounting position, the recording paper P in the case portion 11 is detected by a recording paper presence / absence detection sensor 2 arranged in the apparatus main body. The recording paper presence / absence detection sensor 2 causes the operating lever 2a to protrude into the case portion 11, and the operating lever 2a
, The presence or absence of the recording paper P is detected.

A paper feed roller 30 is arranged in the apparatus main body. The paper feed roller 30 is held at an initial position where the cutout face 31a faces the recording paper P when not in operation as described above. .

The paper feed cassette 10 includes a transport guide path 13 composed of opposing guide surfaces 13a and 13b for guiding recording paper P separated and fed from the inside of the case portion 11, and a lower paper feed cassette (not shown). ), The guide surfaces 14a opposed to each other for guiding the recording paper P conveyed from
A transport guide path 14 consisting of 14b is formed. A pressure roller 15 is provided in the transport guide path 13 and the transport guide path 1
The pressure roller 1 is located near the confluence of the conveying guide path 3 and the conveying guide path 14.
6 are arranged respectively. At the mounting position, the pressure rollers 15 and 16 abut against the drive rollers 3 and 4 of the apparatus main body to form a pair of rollers. These roller pairs are configured as registration roller pairs or transport roller pairs depending on the presence or absence of a clutch in the drive mechanism of the drive rollers 3 and 4.

A recording paper passage detection sensor 5 is disposed below the driving roller 4.
Has the distal end of the operating lever 5a inserted into an opening 14c provided to form a concave portion on the guide surface 14b facing in the off state.

The paper cassette 10 at the mounting position is removed from the apparatus main body by moving in the direction of arrow A1. Rear plate 11b suspended from bottom plate 11a of case 11
Is formed with a notch 11c. By forming the cutout portion 11c in the rear plate 11b, even when the paper feed roller 30 is in the non-initial position at the time of attachment / detachment, the paper feed cassette 10
Can be prevented, and the recording paper presence / absence detection sensor 2 can be prevented from contacting the paper feed cassette 10.

FIG. 2 is a perspective view showing a part of the sheet cassette in the present embodiment in a sectional view.

On the opposing guide surfaces 13a, 13b, 14a, 14b in the transport guide paths 13, 14, a rib-shaped portion 17 extending in the transport direction is formed. Since the recording paper P is transported in the transport guide paths 13 and 14 in contact with the rib-shaped portion 17, the contact area with the paper feed cassette 10 is reduced.

A handle 10a is arranged on a side surface of the paper feed cassette 10 so that a user can grip the paper feed cassette when attaching and detaching the paper feed cassette 10, and a guide member 18 which slides on a guide rail of an apparatus main body to be described later is formed. An engagement lever 19 urged in the direction of arrow B by a leaf spring (not shown) arranged in the inside 10 protrudes from the inside.

By arranging the handle 10a on the sheet cassette 10, the user can apply a force in the detaching direction to the sheet cassette 10 via the grip 10a that can be gripped. Can be improved.

FIG. 3 is an explanatory diagram of the attachment / detachment operation of the sheet cassette in the present embodiment.

The paper cassette 10 inserted through the insertion slot 6 of the apparatus main body is guided by a guide member 18 against the guide rail 7.
And is moved in the direction of arrow A2. When the paper cassette 10 reaches the mounting position, the engagement lever 19 is
The paper feed cassette 10 is positioned by being fitted into an engagement groove 7a formed on the upper surface of the guide rail 7 by the urging force. Further, when the paper cassette 10 is removed, a force is applied to the paper cassette 10 in the direction of the arrow A1 to move the paper cassette 10 from the mounting position, so that the engagement lever 19 is pushed up along the engagement groove 7a against the urging force. And is separated from the engagement groove 7a.

When the engagement lever 19 is inserted, the sheet cassette 10 is moved in the direction indicated by the arrow A1 in comparison with the case where the engagement lever 19 is not inserted.
Since the force required to move the paper cassette in the direction increases, the user can determine whether the paper cassette 10 is at the mounting position or the non-mounting position based on the difference in the force applied to the handle 10a.

FIG. 4 is a configuration diagram of the pressure roller in the present embodiment.

A conductive plate 20 fixed to the sheet cassette 10 is in elastic contact with the pressure roller shaft 16 a of the pressure roller 16. By pressing the conductive plate 20 against the pressure roller shaft 16a, the pressure roller 16 is
To a conductive state.

Further, in the mounting position, the guide member 18 of the paper feed cassette 10 is connected to the guide rail 7 of the apparatus main body.
, The sheet cassette 10 is in a conductive state with respect to the apparatus main body.

Although not shown, the other pressure roller 15 has a similar configuration, and the pressure roller 15 is conductive with respect to the sheet cassette 10.

Referring to FIG. 1, the recording paper P in this embodiment is
The paper feed operation and the transport operation for the printer will be briefly described.

The control unit (not shown) determines the presence or absence of the recording paper P based on the recording paper presence / absence detection signal output from the recording paper presence / absence detection sensor 2, and feeds the paper by inputting an external paper feed signal. Start operation.

The feed roller 30 is rotated from the initial position in the direction of arrow C to bring the circumferential portion into contact with the uppermost recording sheet P, thereby moving the uppermost recording sheet P toward the transport guide path 13. Feed separately. The recording paper P fed separately is fed to the drive roller 3
The sheet is conveyed through the conveyance guide path 13 while being pinched by a pair of rollers including a pressure roller 15 and the conveyance guide path 1.
The recording paper passage detection sensor 5 disposed near the junction with the recording paper 4 contacts the operating lever 5a and is detected. The recording paper P conveyed in the conveyance guide path 14 is similarly detected by the recording paper passage detection sensor 5.

The control unit, which has determined the position of the recording paper P based on the detection signal from the recording paper passage detection sensor 5, removes the recording paper P at the contact portion of the registration roller pair including the driving roller 4 and the pressure roller 16. The recording paper P is temporarily stopped, and the conveyance of the recording paper P is started again at a predetermined timing to the image forming section of the apparatus main body (not shown).

According to the present embodiment described above, the conductive plate 20 is elastically contacted with the pressing roller shaft 16a of the pressing roller 16 at the time of feeding and feeding, so that the pressing roller 16 The pressure roller 15 is made conductive by the same configuration, so that frictional charging of the pressure rollers 15 and 16 can be prevented. Surface 13a,
By forming the rib-shaped portions 17 on the portions 13b, 14a, and 14b, the contact area of the sheet cassette 10 with the recording paper P can be reduced. By making the paper cassette 10 conductive with respect to the apparatus main body, the potential of the paper cassette 10 can be set to the same level as that of the apparatus main body. Since the occurrence can be prevented, it is possible to prevent the malfunction from occurring in the device due to the spark. Further, since the tip of the operating lever 5a of the recording paper passage detection sensor 5 is inserted into the opening 14c formed in the guide surface 14b, even if the position of the operating lever 5a is changed, the operating lever 5a remains within the insertion length. If present, transport guide path 1
The recording paper P passing through the insides 3 and 14 is reliably moved to the operation lever 5a.
, The recording paper passage detection sensor 5 can reliably detect the recording paper P passing through the conveyance guide paths 13 and 14, thereby preventing the occurrence of a malfunction in device control.

Further, since the cut-off portion 11c is formed in the rear plate 11b of the case portion 11, the case portion 11 and the feed roller 30 can be removed even when the feed roller 30 is not at the initial position due to a power failure, a failure or the like. Is not in contact with the main body, the paper cassette 10 can be attached to and detached from the apparatus main body, and the recording paper P can be directly detected by arranging the recording paper presence / absence detection sensor 2 in the case portion 11. The mechanism for detecting the recording paper P can be simplified.

FIG. 5 is a front view showing the paper feed rollers and the rotary shaft in this embodiment.

FIGS. 6 and 7 are side views showing the feed roller and the rotating shaft in this embodiment.

FIG. 6 is a side view from the direction of arrow D shown in FIG. 5, and FIG. 7 is a side view from the direction of arrow E shown in FIG.

As shown in FIG. 6, two fitting pins 1a and 1b having different lengths are implanted on the rotating shaft 1 in the same diameter direction. Further, a U-shaped external fitting groove 31c is formed on the cutout surface 31a of the core portion 31 so as to externally fit the rotary shaft 1, and the fitting pin 1 described above is further formed in the external fitting groove 31c.
a, 1b are fitted, and fitting grooves 34a, 34b corresponding to the lengths of the fitting pins 1a, 1b are formed.

The paper feed roller 30 externally fitted to the rotary shaft 1 is moved in the direction of the arrow D with its position in the rotation direction adjusted, so that the insertion pins 1a and 1b respectively move to the side surfaces 31.
From d, they are fitted into the fitting grooves 34a and 34b.

Since the paper feed roller 30 has a semicircular shape with a cutout surface formed in a part thereof, in order to come in contact with and separate from the recording paper P at a predetermined timing during rotation, the rotation of the rotary shaft 1 in the rotation direction is required. Must be fixed in place.

The lengths of the fitting pins 1a and 1b are different, and the shapes of the fitting grooves 34a and 34b correspond to the lengths of the fitting pins 1a and 1b. Insert the insertion pin 1b into the insertion groove 3 in the groove 34a.
4a, the paper feed roller 30 can be always fixed at a predetermined position of the rotary shaft 1 in the rotation direction.

The insertion pins 1a, 1b are inserted into the insertion grooves 34a, 34.
b, the fixing ring 35 is
Is fitted and pressed against the side surface 31e.

Since the fixing ring 35 has a cut in the circumferential direction and has elasticity in the circumferential tangential direction, the width of the cut is elastically changed by pressing or pulling the rotating shaft 1. It is configured to be detachable.

When the fixing ring 35 is pressed against the side surface 31e, the fitting pins 1a and 1b are moved into the fitting grooves 34a and 34b.
The paper feed roller 30 is fixed in the axial direction to abut the bottom of the paper feed roller.

The feed roller 30 is fixed by fitting the fitting pins 1a and 1b into the fitting grooves 34a and 34b in the rotation direction, and furthermore, a fixing ring 35 that is detachable in the axial direction is fitted to the rotating shaft 1. Therefore, it can be easily attached to and detached from the rotary shaft 1 without using a tool such as a screwdriver.

Further, on the side surface 31d of the core portion 31, an inclination preventing portion 36 having a surface which is in close contact with the rotating shaft 1 is vertically provided, and it is provided that the sheet feeding roller 30 is inclined with respect to the rotating shaft 1. Preventing.

Since the feeding roller 30 can be prevented from being tilted by the tilt preventing portion 36, the area of contact with the recording paper P is always constant, and the recording paper P can be separated and fed stably.

[0056]

As described above, according to the present invention,
An outer fitting groove of a semicircular feed roller having a partially cutout surface formed therein, two fitting pins of different lengths implanted on a rotating shaft, and formed in the outer fitting groove, and further fitted therein. Two feeding grooves corresponding to the length of the pin and a fixing ring fitted to the rotating shaft and abutting against the side surface of the feeding roller make the feeding roller easily detachable from the rotating shaft. Therefore, it is possible to reduce the time required for replacing the paper feed rollers and the time required for assembling the apparatus, and to always assemble the positional relationship between the rotating shaft in the rotation direction and the cut surface of the paper feed rollers in a constant manner. The work of adjusting the position of the paper feed roller in (1) can be dispensed with, and the inclination preventing member that is in close contact with the rotation shaft disposed on the paper feed roller can prevent the paper feed roller from being inclined with respect to the rotation shaft. Therefore, the contact area of the feed roller against the recording paper It can stably perform separation feeding since a constant.

[Brief description of the drawings]

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

FIG. 2 is a perspective view in which a part of a sheet cassette in the present embodiment is a cross-sectional view.

FIG. 3 is an explanatory diagram of an attaching / detaching operation of a sheet feeding cassette in the embodiment.

FIG. 4 is a configuration diagram of a pressure roller in the present embodiment.

FIG. 5 is a front view showing a sheet feed roller and a rotation shaft in the present embodiment.

FIG. 6 is a side view illustrating a feed roller and a rotation shaft according to the present exemplary embodiment.

FIG. 7 is a side view showing a sheet feed roller and a rotation shaft in the present embodiment.

FIG. 8 is a front view showing an example of a paper feed roller and a rotating shaft in a conventional paper feed device.

FIG. 9 is a side view of the paper feed roller shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotating shaft, 1a, 1b ... Insertion pin, 2 ... Recording paper presence detection sensor, 5 ... Recording paper passage detection sensor, 5
a: operating lever, 7: guide rail, 7a: engagement groove, 10: paper cassette, 10a: handle, 13,
14: conveyance guide path, 13a, 13b, 14a, 14
b: guide surface, 14c: opening, 17: rib-shaped part, 19: engaging lever, 20: conductive plate, 30: feeding roller, 34a, 34b: fitting groove, 35: fixing ring, 36: inclination preventing member .

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI B65H 7/04 B65H 7/04

Claims (2)

(57) [Claims] 1. A semicircular shape having a partially cut surface.
And is provided on the rotating shaft and specified during rotation to feed separately.
Paper feed roller that comes in contact with and separates from the recording paper
In the paper feeding device, two rotating shafts having different lengths are provided.
An insertion pin is implanted, and the feed roller is
An outer fitting groove which is opened on the outer peripheral surface for external fitting so that
To fix the paper feed roller in the rotation direction,
The above-mentioned two fitting pins having different lengths are removably fitted.
Forming two fitting grooves corresponding to the lengths of the fitting pins;
In addition, in order to fix the feed roller in the axial direction of the rotating shaft,
Attach the fixing ring that contacts the side of the paper roller to the rotating shaft.
Removably fit so that the notched surface is at a predetermined position
A sheet feeding device, wherein the semicircular sheet feeding roller is arranged on the rotating shaft . 2. The paper feed roller disposed on the rotating shaft
In order to prevent tilting, the feeding roller
2. The sheet feeding device according to claim 1, further comprising a tilt preventing member provided to be in close contact with the sheet feeding device.