JP3456326B2 - 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 sheet feeding device provided in an image recording apparatus such as a printer, a copying machine, and a facsimile device, and a method for removing and assembling a feeding roll , and more particularly, a sheet feeding cassette. Multiple sheets of paper stored in
Paper feeding device including a separating device for separating and feeding the sheets one by one
And the method for removing and assembling the feed roll .

[0002]

2. Description of the Related Art When supplying paper to an image recording apparatus such as a printer, a copying machine or a facsimile machine, a separating apparatus is used which separates the paper contained in a paper feed cassette one by one. For example, in the paper feeding device disclosed in Japanese Unexamined Patent Publication No. 6-144620, the paper is sorted as follows.
FIG. 8A is a side view showing a conventional sorting device.
(B) is a plan view of a main part. In the drawing, the cassette plate 100 is pushed upward by the compression spring 101 at the timing of feeding the paper P, and the cassette plate 10
The upper surface of the sheets P stacked on 0 is the feed roll 10
Pressed to 2. On the other hand, a friction member 103 is arranged so as to face the feed roll 102. The friction member 10
3 is supported by a supporting member 105 having a pivot 104 at its end, and is pressed against the feed roll 102 by a compression spring 106.

With such a configuration, the feed roll 102
When is rotated counterclockwise in the figure, the uppermost one of the stacked sheets P is sent out in the sheet feeding direction. At this time, when two sheets are fed at the same time, the lower one of the upper and lower two sheets is locked by the friction member 103 and is not fed out, and only the upper one in contact with the feed roll 102 is fed out.

By the way, since the friction member 103 is worn out for a long period of time, it must be replaced regularly. In order to facilitate the replacement of the friction member 103, the above-mentioned loosening device has the following configuration. Figure 8 (b)
In, the pivot 104 is supported by the bearing portion 107 of the base 106. When exchanging the friction member, the support member 105 is picked up by hand and bent as shown by the chain double-dashed line in the figure, so that the pivot 104 is pulled out from the bearing portion 107.

Since the feed roll 102 also wears due to wear, it is desirable to replace it regularly. For example,
In the feed roll disclosed in Japanese Unexamined Patent Publication No. 4-75934, a pin is provided integrally with the roll in the radial direction of the feed roll, and the pin can be inserted into and removed from the shaft of the feed roll. Therefore, when the feed roll is attached to or detached from the shaft, the engagement between the pin and the pin hole may be released.

[0006]

The above-mentioned conventional paper feeder has the following problems. First, in a loosening device in which a friction member is supported by a support member and pivotally supported by a pivot, it is necessary to bend the support member when replacing the friction member. Therefore, in order to obtain a desired deflection amount, the support member 105
It is necessary to lengthen the length to some extent. Therefore, there is a problem that the size of the entire sorting device becomes large. Further, when the support member 105 is long, the rattling between the pivot and the bearing portion is enlarged at the position of the friction member, so that there is a great deal of rattling during operation and the service life is likely to be shortened. is expected.

Further, in the above-mentioned device in which the feed roll is engaged with the shaft by the pin, the pin is integrally formed of the same material as the core material of the feed roll, and therefore the strength of the pin depends on the material selected. May run short. Generally, the core of the feed roll is made of a resin material from the viewpoint of weight saving and cost, so in order to secure the strength, for example, it is necessary to separate the pin from the core as a metal material, and the assembly process is complicated. Expected to become.

[0008] The present invention is to solve the above problems, is easy replacement of consumable parts, and the sheet feeder and a feed roll comprising a handling device which can be stabilized and the life of the separating operation
The purpose is to provide a method for removing and assembling the.

[0009]

Means for Solving the Problems The present invention for solving the above-mentioned problems and for achieving the object, is formed in a feed roll,
At least half or more of the circumference is in the outer peripheral direction except the outer circumference of the partial circle.
An open shaft hole and a rotating member formed on the inner circumference of the shaft hole.
The stop groove and the flexibility that extends axially from the core roll
Holds the locking claws that it has and the feed roll and core roll
It is provided on a common shaft that moves the feed roll in the axial direction.
It can be slid and engaged, the direction of rotation of the feed roll
Member for restricting the movement of the shaft and the circumferential direction of the shaft
Is formed on the shaft of the core roll by engaging the locking claws.
With a sliding lock groove for restricting movement in the direction
The distance between the sliding lock groove and the lock member should be such that
When fitted in the sliding locking groove, the locking member rotates and locks
The feature is that the size is set so that it fits in the groove .

[0010]

[0011]

According to this feature , by pulling out the locking claw from the sliding locking groove and shifting the core roll, the movement of the feed roll regulated by the core roll in the axial direction becomes free, and the locking member is locked. It is possible to release the engagement between the rotation locking groove and. After releasing the engagement, the feed roll can be easily removed from the shaft in the radial direction by utilizing the open portion of the shaft hole of the feed roll.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view of a main part of a sheet feeding device according to an embodiment of the present invention. In the figure, two pairs of a half-moon-shaped feed roll 2 and a core roll 3 for preventing further feeding are attached to a shaft 1 rotatably supported by a base bearing (not shown). The diameter of the feed roll 2 is set larger than that of the core roll 3, and the core roll 3 is not regulated in the rotational direction with respect to the shaft 1. The feed roll 2 and the core roll 3 have an engaging structure such that they can be easily attached to and detached from the shaft 1 by means of the claws 20, the rotation locking groove 22, etc., which will be described later.

A driven gear 4 partially lacking teeth is fixed to the shaft 1, and a drive gear 5 is engaged with the driven gear 4. A tension spring 7 is hooked on a pin 6 standing on the side surface of the driven gear 4, and the driven gear 4 is biased in the direction of an arrow 8.

Although the drive gear 5 is constantly rotating in the direction of arrow B, the driven gear 4 has its tooth missing portion at the drive gear 5.
Is disengaged, and the driven gear 4 is free to rotate. In this state, the driven gear 4 is biased by the tension spring 7 in the sheet conveying direction, that is, the direction of arrow A, so that the driven gear 4 tries to rotate in the direction A.

A locking portion 10a is formed on the boss 10 of the driven gear 4. The engagement portion 10a engages with the claw portion 12a of the movable plate 12 above the solenoid 11 arranged adjacent to the boss 10, whereby the free rotation of the driven gear 4 is prohibited. That is, when power is not supplied to the solenoid 11, the claw portion 12a at the tip of the movable plate 12 is urged upward by the action of the tension spring 11a, and as a result, the claw portion 12a is locked by the boss 10. Engage with 10a. On the other hand, when power is supplied to the solenoid 11, the movable plate 12 is attracted to the magnetic core, so that the claw portion 12a is urged downward, and the claw portion 12a and the locking portion 10a are disengaged. As a result, the driven gear 4 is biased by the tension spring 7 to rotate in the direction of the arrow A, and again engages with the drive gear 5. In this way, by controlling the power supply to the solenoid 11, the driven gear 4 is intermittently driven when necessary to rotate approximately once, and the paper is fed by the feed roll 2.

The cassette plate 13 is for loading sheets and is biased from below by a compression spring (not shown). Reference numeral 14 is a seat of the compression spring. Edges 13a and 13b on both sides of the tip of the cassette plate 13 are engaged with cams 15 and 16 fixed to the shaft 1, and are vertically moved by being driven by the cams 15 and 16. FIG. 1 shows a state where the cassette plate 13 is pushed downward by the cams 15 and 16.

At the time of feeding the paper, the solenoid 11 is energized so that the claw portion 12a of the movable plate 12 and the locking portion 10 of the boss 10 are engaged.
The engagement with a is released and the shaft 1 rotates, and accordingly the cams 15 and 16 also rotate in the arrow A direction. Therefore, the downward biasing of the cams 15 and 16 is released, and the cassette plate 13 rises. When the cassette plate 13 rises, the circumferential portion of the feed roll 2 is rotated downward from the state shown in the figure at that time, so the upper surface of the sheet placed on the cassette plate 13 is pressed by the feed roll 2. Be paid out.

A friction member 17 is arranged so as to face the feed roll 2 and the core roll 3, and the sheet pulled out from the cassette plate 13 is fed between the friction member 17 and the feed roll 2. At this time, the leading edges of the sheets contact the friction member 17 at an optimal angle set in advance, so that the overlapped sheets are unraveled, and usually only one sheet is fed. The angle is adjusted so that two or more sheets are not fed even when the "unraveling" action is insufficient.

When two sheets are fed, the lower sheet comes into contact with the friction member 17 and receives a resistance force.
Only the upper one sheet is conveyed to the next feeding process (not shown). When the upper sheet is fed by the circumferential length of the feed roll 2, the sheet is sandwiched between the core roll 3 and the friction member 17. In this way, by pressing the sheet with an appropriate force, the lower sheet continues to receive the resistance force of the friction member 17 until the upper sheet is completely fed. As a result, so-called additional feeding does not occur even if the upper sheet is pulled.

The friction member 17 is held on the base 17a by adhesion or the like. The friction member 17 is made of a material such as rubber or foamed urethane rubber that provides high friction resistance. However, it is desirable to select a roller having a friction resistance smaller than that of the periphery of the feed roll 2. Friction member 17
The base 17a and the support shaft 17b are integrally made of plastic. The friction member 17 is supported by supporting the support shaft 17b with a bearing of a support plate 18, and details thereof will be described later with reference to FIG.

Next, the structure of the joint between the feed roll 2 and the core roll 3 (roll portion) and the shaft 1 will be described. Figure 2
Is a perspective view of the roll portion, and FIG. 3 is a plan view of the same. In addition, the front view of the feed roll 2 is shown in FIG.2 (b). 2 and 3, an engaging groove 19 is formed in the shaft 1.
The engagement grooves 19 are formed in the circumferential direction of the shaft, and are provided at two locations corresponding to the arrangement positions of the core rolls 3. The claw 20 formed on the core roll 3 is engaged with the engagement groove 19.

Further, a pin 21 is driven in the shaft 1 in the radial direction thereof. The pins 21 are preferably made of metal, and are provided at two positions corresponding to the positions where the feed rolls 2 are arranged. An engaging groove 22 is formed in the feed roll 2 at a position corresponding to the pin 21, and the pin 21 engages with the engaging groove 22 when mounted. In addition, pin 2
The key 1 and the engagement groove 22 may be replaced with a key and a key groove, respectively.

The positional relationship between the engaging groove 19 and the pin 21 is such that the pin 21 is fitted in the engaging groove 22 when the claw 20 is fitted in the engaging groove 19. Set. With such a positional relationship, the feed roll 2 cannot be attached to or detached from the shaft 1 when the pawl 20 is fitted in the engagement groove 19. Therefore, the following procedures are taken when attaching and detaching.

The procedure for mounting the feed roll 2 on the shaft 1 will be described with reference to FIG. First, the claw 20 is bent to disengage it from the engaging groove 19, and the core roll 3 is slid on the shaft 1 so that the feed roll 2 can be fitted to the shaft 1 (FIG. 4A). Next, the feed roll 2 is fitted to the shaft 1 (FIG. 4 (b)). Subsequently, the feed roll 2 is slid on the shaft 1 to engage the engagement groove 22 with the pin 21, and further, the core roll 3 is displaced to a position where the claw 20 engages with the engagement groove 19 and the procedure is completed. (See FIG. 3). In order to remove the feed roll 2 from the shaft 1, the procedure reverse to this procedure may be executed.

Next, the support structure of the friction member 17 will be described. FIG. 5 is a perspective view showing the support structure of the friction member 17, and FIG. 6 is a side view of the friction member 17. In FIG. 5, the support plate 18 has an upper bearing 23 and a lower bearing 24, and supports the support shaft 17b by a bearing structure divided into upper and lower parts. The cross section of the support shaft 17b has a shape in which a part of the circumference is deleted (so-called D cut) in the vicinity of the root portion thereof, and in the vicinity of the tip end thereof, a surface parallel to the deleted surface is formed from the D cut. Therefore, a part of the circumference is deleted (so-called double D cut). The sectional shape of the support shaft 17b is described in detail in FIG. It should be noted that one of the two surfaces near the tip portion formed by the double D-cut is on the same plane as the surface near the root portion formed by the D-cut.

Further, in FIG. 6, a compression spring 25 is arranged between the back surface of the base 17a and the support plate 18. The repulsive force of the compression spring 25 acts as a force for urging the friction member 17 counterclockwise in the drawing with the support shaft 17b as the center, and the friction member 17 is pressed against the feed roll 2. In addition,
A protrusion 17c is provided on the back surface of the base 17a with a clearance C between the base 17a and the support plate 18. This protrusion 17c
Thus, for example, even if the friction member 17 is retracted due to the rigidity of the cardboard when the cardboard having high rigidity (so-called strong stiffness) is fed in, after the projection 17c abuts, the The friction member 17 does not rotate. Therefore, the clearance between the feed roll 2 and the friction member 17 does not become too large, and double feeding can be avoided.

Next, a support shaft 17 for the support plate 18
The engagement state of b will be described. FIG. 7 shows the support shaft 17b.
It is a figure which shows the relationship between the support plate 18 and the support shaft 17b when it sees from the front end side, and is sectional drawing in the AA position and BB position of FIG. In the figure, a gap G is formed between the lower surface 23a of the upper bearing 23 and the upper surface 24a of the lower bearing 24.
Is secured. The gap G is set to be slightly larger than the thickness t of the support shaft 17b that has been double-D cut, that is, the distance between two parallel surfaces that are formed by double-D cut.

From the relationship between the thickness t and the size of the gap G, as shown in FIGS. 7 (a) and 7 (b), the support shaft 17b is formed.
Is the gap G formed by the bearings 23, 24 of the support plate 18.
Can be fitted into the bearings 23, 24 by passing through.
Further, the support shaft 17 inserted into the upper bearing 23 and the lower bearing 24
When b is rotated 90 degrees, the state shown in FIG. As can be seen from FIG. 7C, the support shaft 17b is supported by the upper bearing 23 in the circumferential region α of the support shaft 17b, and the support shaft 17b is supported by the lower bearing 24 in the region β. . In this way, since the support shaft 17b is supported by the bearing substantially in the circumferential direction (α + β), there is little rattling in the bearing and high support strength is obtained. In order to remove the support shaft 17b mounted on the support plate 18, the support shaft 17b
2 formed by rotating the b and performing the double D cut
One surface may be parallel to the lower surface 23a of the upper bearing 23 and the upper surface 24a of the lower bearing 24 and may be pulled out toward the front.

[0030]

As is apparent from the above description, the claims
According to the first to third aspects of the invention, the feed roll is opened through the open portion of the shaft hole.
Of the core roll can be attached to and detached from the shaft.
Simply attach and detach and slide the core roll on the shaft.
Position the feed roll on the shaft and fix it,
Easy to replace the feed roll as it can be removed
Is.

[0031]

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a sheet feeding device according to an embodiment of the present invention.

FIG. 2 is a perspective view of a roll unit according to the embodiment of the present invention.

FIG. 3 is a plan view of a roll unit.

FIG. 4 is a plan view of a roll portion when the core roll is displaced.

FIG. 5 is a perspective view of a friction member support portion.

FIG. 6 is a sectional side view of a friction member support portion.

FIG. 7 is an enlarged sectional side view of a friction member support portion.

FIG. 8 is a side view and a plan view of relevant parts of a conventional paper feeding device.

[Explanation of Codes] 1 ... Shaft, 2 ... Feed Roll, 3 ... Core Roll, 4 ...
Driven gear, 5 ... Drive gear, 11 ... Solenoid, 1
3 ... Cassette plate, 15, 16 ... Cam, 17 ... Friction member, 17a ... Support shaft, 17b ... Base

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-201570 (JP, A) JP-A-5-286586 (JP, A) JP-A-1-294131 (JP, A) Actual Kaihei 6- 82054 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B65H 3/52 310 B65H 3/06 330 G03G 15/00 516

Claims (3)

(57) [Claims] 1. A sheet feeding device, in which a feed roll and a core roll for preventing further feeding of paper are arranged adjacent to each other and mounted on a common shaft, wherein a shaft hole formed in the feed roll and opened at least half a circumference or more. A rotation locking groove formed on the inner circumference of the shaft hole, a locking claw having flexibility extending in the axial direction from the core roll, and the feed roll provided on the shaft in the axial direction. A locking member that can be slid on the shaft to engage with the rotation locking groove and that restricts the movement of the feed roll in the rotation direction; and the locking claw that is formed in the circumferential direction of the shaft. A sliding engagement groove for engaging and restricting the axial movement of the core roll, wherein the distance between the sliding engagement groove and the engagement member is such that the engagement claw is the sliding engagement groove. Set the dimensions so that the locking member fits in the rotation locking groove when it fits in the stop groove. A paper feeding device characterized by being provided. 2. The method of removing a feed roll of a sheet feeding device according to claim 1, wherein the engaging claw is bent to release the engagement between the sliding engaging groove and the engaging claw, the core roll is slid in the direction away from the feed roll on said shaft, said feed roll locking of the shaft and the rotation locking groove of the roll Ri said transmission is slid in a direction closer to the core roll on said shaft A method for removing a feed roll of a sheet feeding device, comprising: disengaging a member and removing the feed roll from the shaft through an opening portion of the shaft hole. 3. The method of assembling a feed roll of a sheet feeding device according to claim 1, wherein the feed roll is attached to the shaft through an open portion of the shaft hole, and the feed roll is slid on the shaft. The rotation locking groove of the feed roll is engaged with the locking member of the shaft, the core roll is slid on the shaft in a direction approaching the feed roll, and the locking claw is slid and locked. A method of assembling a feed roll of a sheet feeding device, characterized by engaging with a groove.