JP2002240974A - Separation paper feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a stable separation paper feed, by forming many protrusion parts piercing a paper sheet in a conveying roller and a returning roller in a separation paper feeder of ERR system to prevent a tip end part of this protrusion part from abrasion. SOLUTION: A conveying/returning roller 5, 8, in the case of the paper sheet reaching its nipple part, is placed in a released condition, the conveying/ returning roller 5, 8, after the paper sheet reaches between thereof, are brought into contact with each other. In this way, a protrusion part 9 of the conveying roller 5 coming into contact with the returning roller 8 to rotate and a protrusion part 9 of the returning roller 8 coming into contact with the conveying roller 5 to rotate are prevented, abrasion of the respective protrusion part 9 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an FRR type separation sheet feeding apparatus.

[0002]

2. Description of the Related Art A conventional example of an FRR type sheet feeder will be described with reference to FIG. The paper S stacked on the paper feeding unit is guided by the front guide plate 101 and rises while the front surface (tip side) in the transport direction is aligned, and is contacted with the paper S only when the paper is transported. The first sheet S1 moves in the transport direction. Note that the call roller 103 moves to the retracted position except when the sheet is conveyed, and does not contact the sheet S.

[0003] When the first sheet S1 is conveyed, the second sheet S2 thereunder may also be fed together due to friction between the sheets, and the sheets S1 and S2 are moved in the conveying direction. A torque for transmitting only a desired frictional torque to a transport roller 105 made of an elastic material, which rotates in the transport direction by a rotating transport roller drive shaft 104, and a return roller drive shaft 106, which is opposed to the transport roller 105 and rotates in a return direction. The rotating elastic return roller 108 is sent via the limiter 107 to an area where the rotating roller 108 is in contact with the desired pressing force.

When the first sheet S1 and the second sheet S2 enter the nip portion between the transport roller 105 and the return roller 108 in a state where they are overlapped, the first sheet S1 is transported by the transport force of the transport roller 105. Is sent in the direction, but the second sheet S
2 is pushed back by the conveyance force of the return roller 108 rotating in the return direction, and is in a state of waiting on the upstream side between the rollers 105 and 108.

Further, as shown in FIGS. 4 and 5, the applicant of the present application has proposed a FRR system using a transport roller 110 of high rigidity and a return roller 111 having a large number of protrusions 109 in the circumferential direction. Japanese Patent Application Laid-Open No. 2000-2000
362368 and JP-A-2000-390746. FIG. 4 shows that there is no paper between the transport roller 110 and the return roller 111, and the gear 112 formed on one end of the transport roller 110 and the gear 113 formed on one end of the return roller 111 mesh with each other. Return roller 1
11 is a state in which the sheet is rotated in the sheet conveyance direction by the conveyance roller 110. FIG. 5 shows a state in which one sheet of paper S has entered between the transport roller 110 and the return roller 111. The projection 109 of the transport roller 110 and the projection 109 of the return roller 111 pierce the paper S,
This is a state in which the return roller 111 is rotated by the transport roller 110 in the paper transport direction.

Here, a material having high rigidity refers to a material having a longitudinal elastic modulus (Young's modulus) of 1 GPa or more.
~ 210GPa), titanium (116GPa), aluminum (70.3GPa),
Glass (71GPa), polycarbonate with glass fiber (10.8
~ 3.1GPa), alumina (3800GPa), alumina ceramics
(3000 GPa).

[0007]

As shown in FIG. 4 and FIG. 5, an F which stabs the paper S with a highly rigid projection 109 to obtain the conveyance force and the separation force of the paper S.
In the RR method, the projection height of the projection 109 is related to the thickness of the sheet S to be used. In an extreme case, if the projection height is greater than the sheet thickness, a hole is formed in the sheet S and the paper surface is broken (hole damage). At the same time, there is an adverse effect such that white spots are deteriorated in image formation quality.

Further, when a plurality of sheets S to be separated exist between the transport roller 110 and the return roller 111,
If the height of the projection> the thickness of the sheet, the projection 109 will skew the plurality of sheets S, and the original sheet separation function will not work.

In this case, a structure is adopted in which the projection height of the projection 109 of both rollers 110 and 111 is set to be equal to or less than the thickness of the sheet. When the return roller 111 is in direct contact and rotation, the vertices of the projections 109 are in contact with the tooth bottoms of the mating rollers 111 and 110 and are abraded and deformed. In some cases, the performance of piercing the sheet S is reduced, and the separating / feeding performance is reduced.

The transport roller 110 and the return roller 11
In FIG. 1, since the sheet S is rotating with a fixed pressing force set, the sheet S tends to buckle due to the sheet leading edge load when the sheet S enters the nip portion between the transport roller 110 and the return roller 111.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a separation sheet feeding apparatus capable of preventing abrasion of a tip of a projection and performing stable separation sheet feeding.

Another object of the present invention is to provide a separation sheet feeding device capable of preventing buckling of a sheet due to a load on the leading edge of the sheet when the sheet enters a nip portion between a conveying roller and a return roller. .

[0013]

According to the first aspect of the present invention,
FRR that separates and feeds paper with transport rollers and return rollers
In the separation sheet feeding device of the system, the transport roller and the return roller are rollers of high rigidity having a large number of protrusions in the circumferential direction, and the paper is transported by the transport roller and the return roller. When the paper reaches the nip portion, the transport roller and the return roller are released, and after the paper reaches the transport roller and the return roller, the transport roller is released.
Roller so that the roller contacts the return roller.
The roller and the return roller are provided so as to be able to come and go.

Here, when the transport roller and the return roller are in the released state, the transport roller and the return roller are separated from each other, and the projection of the transport roller and the projection of the return roller are opposite to each other. Or, it means that it is in a state where it does not contact the transport roller. The contact between the transport roller and the return roller means that the transport roller and the return roller are in a state of nipping the sheet.

Therefore, when the paper reaches the nip between the transport roller and the return roller, the transport roller and the return roller are in the released state, and the protrusion of the transport roller contacts the return roller and rotates. In addition, since the protrusion of the return roller is prevented from rotating in contact with the transport roller, wear of each protrusion is prevented, the performance of piercing the protrusion to the paper is maintained, and the protrusion is formed on the paper. The performance of separating and feeding the paper, which is performed by piercing the paper, is favorably maintained.

Further, since the conveyed sheet is fed between the conveyance roller and the return roller in the released state, buckling of the sheet when feeding the sheet between the conveyance roller and the return roller is prevented. .

According to a second aspect of the present invention, in the separation sheet feeding apparatus according to the first aspect, a sheet detecting means is provided near a nip between the transport roller and the return roller, and the sheet detecting means is provided. Means for separating the return roller from the transport roller when no paper is detected, and for bringing the return roller into contact with the transport roller when the paper detection means detects a sheet.

Therefore, the transport roller and the return roller are brought into contact with and separated from each other according to the detection result of the paper detecting means.
The transport roller and the return roller can be reliably brought into contact only when a sheet exists between them.

According to a third aspect of the present invention, in the separation apparatus according to the first aspect, the contact / separation signal between the transport roller and the return roller is the same as the start signal of the call roller or the signal of the call roller. The driving signal is set based on a start signal, and the driving of the return roller toward and away from the transport roller and the driving of the calling roller are performed by a common driving source.

Here, the call-out roller is a member that feeds the stacked sheets of paper toward a nip portion between a transport roller and a return roller.

Therefore, the timing of contact and separation between the transport roller and the return roller and the drive for the contact and separation are performed using the start signal of the call roller and the drive source, so that the cost of the apparatus is reduced.

[0022]

FIG. 1 shows a first embodiment of the present invention.
It will be described based on. The sheet called by the call roller 3 advances to a nip portion between the transport roller 5 and the return roller 8. The transport roller 5 and the return roller 8 are rigid bodies having a large number of protrusions 9 as described with reference to FIGS. 4 and 5 in the circumferential direction.

Immediately before the sheet reaches the nip portion between the transport roller 5 and the return roller 8, a sensor 20 serving as a sheet detecting means is used.
To detect the leading edge of the sheet. By this detection signal, the solenoid 17 is sucked, and the lever 18 is
By rotating about a, the return roller driven shaft 6 is pushed downward, and a gap is created between the transport roller 5 and the return roller 8. This gap is a value through which the paper can pass and is 0.1.
It is set to about 1 mm. Then, the sheet is transported by the transport roller 5
The suction of the solenoid 17 is released at the timing when it reaches the nip portion between the feed roller and the return roller 8, and the transport roller 5 and the return roller 8 come into contact with each other to grip the sheet. The timing at which the solenoid 17 is released is set so as to be delayed by a certain time after being sucked, so that when the leading end of the paper passes through the nip portion between the transport roller 5 and the return roller 8, the paper is transported by the transport roller. 5 and the return roller 8 can hold it.

The transport roller 5 is fixed to a transport roller drive shaft 4 driven by a motor (not shown). The return roller 8 has a torque limiter 7 attached to the return roller driven shaft 6.
Gear 6-1 fixed to the return roller driven shaft 6 and a gear 6-3 fixed to a return roller drive shaft 6-4 which is connected to a motor (not shown) and driven to rotate. And are engaged.

The call roller 3 is provided so as to be movable to a position where it comes into contact with or separates from the uppermost sheet of the sheets stacked on a sheet feeding section (not shown), and starts a call operation. The solenoid 15a is sucked by the start signal, and the call roller 3 moves to a position where it comes into contact with the sheet. A drive belt 3 for transmitting a driving force from the transport roller 5 to the call roller 3 is provided between a pulley 3-1 attached to the call roller 3 and a pulley (not shown) attached to the transport roller 5. -2 is wound.

After the paper is fed into the nip portion between the transport roller 5 and the return roller 8, the paper is gripped by the transport roller 5 and the return roller 8, and the projection 9 of the transport roller 5 and the projection of the return roller 8 are formed. The part 9 pierces the sheet. And
When the driving force is transmitted from the motor to the transport roller 5 and the return roller 8, the return roller 8 is rotated by the transport roller 5 when one sheet is gripped,
The paper is transported. When two or more sheets are gripped, the transport roller 5 rotates in the paper transport direction, and the return roller 8 rotates in the paper return direction.
Only one sheet of paper is conveyed, and the other sheets are returned to the paper supply unit.

Next, a second embodiment of the present invention will be described with reference to FIG.
It will be described based on. The same parts as those described in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

The call roller 3 is provided so as to be movable to a position where it comes into contact with or separates from the uppermost sheet of the sheets stacked in the sheet feeding section, and is operated by a start signal for starting the call operation. Is moved to a position where the call roller 3 comes into contact with the sheet.

The solenoid 15 is connected to a pulley 21
a, 21b, and 21c are connected to a lever 18 via a wire 22 stretched around the support shaft 18a. The rotation of the lever 18 causes the return roller driven shaft 6 to move up and down. Then, the return roller 8 is moved toward and away from the transport roller 5.

That is, in the present embodiment, the movement of the call roller 3 to the position for contacting / separating the sheet and the driving for bringing the return roller 8 into contact with / separating from the transport roller 5 are performed by one start signal and one drive signal. The operation is performed using the solenoid 15 as a drive source.

[0031]

According to the first aspect of the present invention, when the paper reaches the nip between the transport roller and the return roller, the transport roller and the return roller are in the released state, and the protrusion of the transport roller is Rotating in contact with the return roller; and
Since the protrusion of the return roller is prevented from rotating in contact with the transport roller, wear of each protrusion can be prevented, the performance of piercing the protrusion into the paper can be maintained, and the protrusion can be pierced into the paper. The separation / feeding performance of the sheet to be performed can be favorably maintained. Further, since the conveyed sheet is sent between the conveyance roller and the return roller in the released state, buckling of the sheet when feeding the sheet between the conveyance roller and the return roller can be prevented.

According to the second aspect of the present invention, the conveyance roller and the return roller are brought into contact with and separated from each other according to the detection result of the paper detection means. Can be reliably brought into contact with only

According to the third aspect of the present invention, the timing of contact / separation between the transport roller and the return roller and the drive for the contact / separation are performed by using a start signal of a call roller and a drive source. This eliminates the need for a dedicated device for bringing the device into and out of the device, and can reduce the cost of the device.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a separation sheet feeding device according to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating a separation sheet feeding device according to a second embodiment of the present invention.

FIG. 3 is a side view showing a conventional separation sheet feeding device.

FIG. 4 is a cross-sectional view showing the contents of the invention of the prior application in which protrusions are formed on a transport roller and a return roller.

FIG. 5 is a cross-sectional view showing the contents of the invention of the prior application in which projections are formed on the transport roller and the return roller.

[Explanation of symbols]

 3 Call Roller 5 Transport Roller 8 Return Roller 15 Drive Source 20 Paper Detecting Means

Continued on the front page (72) Inventor Seiji Hoshino 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. (reference) 3F343 FA02 FB01 FC01 GA03 GB01 GC01 GD01 HD17 JA01 JD04 JD09 JD31 JD33 KB05 MA03 MA13 MA14 MA33 MA54 MB04 MB14 MC11 MC19 MC20

Claims (3)

[Claims] 1. An FRR type separation sheet feeding device for separating and feeding sheets by a conveyance roller and a return roller, wherein the conveyance roller and the return roller are made of a highly rigid material having a large number of protrusions in a circumferential direction. When the paper reaches the nip portion between the transport roller and the return roller, the transport roller and the return roller are released, and the paper is transported by the transport roller. The transport roller and the return roller are provided so as to be able to contact and separate from each other so that the transport roller and the return roller come into contact with each other after reaching the roller and the return roller. A sheet feeding device. 2. A paper detecting means is provided near a nip portion between said transport roller and said return roller, and said paper is returned from said transport roller when said paper detecting means does not detect paper. 2. The separation sheet feeding device according to claim 1, further comprising a unit that separates a roller and causes the return roller to contact the conveyance roller when the sheet detection unit detects a sheet. 3. The contact signal between the transport roller and the return roller is set to be the same as the start signal of the call roller or from the start signal of the call roller, and
2. The separation sheet feeding device according to claim 1, wherein the drive for bringing the return roller toward and away from the transport roller and the driving of the call roller are performed by a common drive source.