JP3633920B2 - Method of removing and assembling the paper feeding device and the separating device - Google Patents

Description

[0001]
BACKGROUND 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 machine, and a method for attaching / detaching a sheet feeding device, and in particular, a plurality of sheets stored in a sheet feeding cassette one by one. The present invention relates to a sheet feeding device including a separating device for feeding separately and a method for removing and assembling the separating device.
[0002]
[Prior art]
When supplying paper to an image recording apparatus such as a printer, copying machine, facsimile machine, or the like, a papering device is used that picks up the paper stored in a paper feed cassette one by one. For example, in a paper feeding device disclosed in Japanese Patent Laid-Open No. 6-144620, paper is rolled as follows. Fig.8 (a) is a side view which shows the conventional peeling apparatus, FIG.8 (b) is a principal part top view. In the drawing, the cassette plate 100 is pushed upward by the compression spring 101 at the supply timing of the paper P, and the upper surface of the paper P stacked on the cassette plate 100 is pressed by the feed roll 102. On the other hand, a friction member 103 is disposed so as to face the feed roll 102. The friction member 103 is supported by a support member 105 having a pivot 104 at its end, and is pressed against the feed roll 102 by a compression spring 106.
[0003]
With such a configuration, when the feed roll 102 rotates counterclockwise in the drawing, the uppermost stacked paper P is fed out in the paper feeding direction. At this time, when the two sheets are fed out simultaneously, the lower one of the upper and lower sheets is locked by the friction member 103 and is not sent out, but only the upper one in contact with the feed roll 102 is sent out.
[0004]
By the way, the friction member 103 is worn out over a long period of time, and therefore needs to be replaced periodically. In the above-described whirling device, the following configuration is adopted to facilitate replacement of the friction member 103. In FIG. 8B, the pivot 104 is supported by a bearing portion 107 of the base 106. When exchanging the friction member, the support member 105 is picked by hand and bent as shown by a two-dot chain line in the drawing to extract the pivot 104 from the bearing portion 107.
[0005]
Since the feed roll 102 is also consumed due to wear, it is desirable to replace it periodically. For example, in the feed roll disclosed in Japanese Patent Laid-Open No. 4-75934, a pin is provided integrally with the roll in the radial direction of the feed roll, and this pin can be freely inserted into and removed from the axis of the feed roll. . Therefore, when the feed roll is attached to and detached from the shaft, the engagement between the pin and the pin hole may be released.
[0006]
[Problems to be solved by the invention]
The conventional paper feeder has the following problems. First, in a rolling device that supports a friction member with a support member and is pivotally supported by a pivot, the support member needs to bend at the time of replacement of the friction member. It is necessary to lengthen the length of 105 to some extent. Therefore, there is a problem that the size of the entire rolling device becomes large. In addition, if the support member 105 is long, the rattle between the pivot and the bearing portion is enlarged at the position of the friction member, so that the backlash during operation becomes severe and the life is likely to be shortened. is expected.
[0007]
Further, in the above-described apparatus in which the feed roll is engaged with the shaft by the pin, since the pin is integrally formed of the same material as the core material of the feed roll, the strength of the pin is insufficient depending on the material selected. Sometimes. In general, the core of the feed roll is made of a resin material from the viewpoint of weight reduction and cost. In order to ensure strength, for example, it is necessary to separate the core from the core using a pin as a metal material, and the assembly process is complicated. It is expected to become.
[0008]
The present invention provides a paper feeding device including a paper feeding device and a method for removing and assembling the paper rolling device, which can solve the above-mentioned problems, can easily replace consumable parts, and can stabilize the paper rolling operation and extend the life. The purpose is to do.
[0009]
[Means for Solving the Problems]
In order to solve the above problems and achieve the object, the present invention is formed on a support shaft of a friction member disposed opposite to a feed roll, and has a predetermined length parallel to the support shaft and in the axial direction of the support shaft. A first flat surface, a second flat surface formed on a support shaft of the friction member, parallel to the first flat surface and having a predetermined length in the axial direction of the support shaft; A first bearing portion arranged corresponding to the first plane, and a bearing comprising a second bearing portion arranged corresponding to the second plane, wherein the first bearing portion and the second bearing portion are Each has a partial inner circumference for supporting the support shaft, and when the first bearing portion and the second bearing portion are viewed in an axial direction, the respective inner circumferences complement each other and are larger. Forming a partial inner circumference and slightly larger than the distance between the first plane and the second plane. Tsu opening having flop is characterized in that it is formed by the first bearing portion and the second bearing portion.
[0010]
According to this feature, the support shaft can be inserted into the bearing from the open portion. Then, by rotating the inserted support shaft within the bearing, the diameter of the support shaft becomes larger than the gap of the open portion when viewed from the inserted direction, and the support shaft is pulled out with respect to the inserted direction. Stable support is possible.
[0011]
The present invention is also characterized in that an elastic body that urges the friction member toward the feed roll and a retraction restricting means for the friction member that restricts the amount of retraction of the friction member toward the elastic body are provided. is there.
[0012]
According to this feature, even when the friction member is pushed back by the sheet, the amount of retraction is limited by the retreat restricting means. Therefore, it is possible to prevent a problem that the friction member is largely retracted and a plurality of sheets are simultaneously fed.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail 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, a pair of a half-moon-shaped feed roll 2 and a core roll 3 for preventing follow-up is mounted on a shaft 1 rotatably supported by a base bearing (not shown). The feed roll 2 is set to have a diameter larger than that of the core roll 3, and the core roll 3 is not restricted in the rotational direction with respect to the shaft 1. The feed roll 2 and the core roll 3 have an engagement structure that can be easily attached to and detached from the shaft 1 by the claw 20, the rotation locking groove 22, and the like. This structure will be described later.
[0014]
A driven gear 4 partially lacking teeth is fixed to the shaft 1, and a driven gear 5 is engaged with the driven gear 4. A tension spring 7 is hung on the pin 6 erected on the side surface of the driven gear 4, and the driven gear 4 is urged in the direction of the arrow 8.
[0015]
The drive gear 5 is always rotating in the direction of the arrow B, but the driven gear 4 is disengaged from the drive gear 5 at the tooth-missed portion, and the driven gear 4 can be freely rotated. In this state, the driven gear 4 is urged by the tension spring 7 in the sheet conveying direction, that is, in the direction of the arrow A, so that the driven gear 4 tries to rotate in the direction A.
[0016]
A locking portion 10 a is formed on the boss 10 of the driven gear 4. The engaging portion 10a engages with the claw portion 12a of the movable plate 12 above the solenoid 11 disposed adjacent to the boss 10, so that free rotation of the driven gear 4 is prohibited. That is, when power is not supplied to the solenoid 11, the claw portion 12 a at the tip of the movable plate 12 is biased upward by the action of the tension spring 11 a, and as a result, the claw portion 12 a becomes the locking portion of the boss 10. 10a is engaged. 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 biased downward, and the claw portion 12a and the locking portion 10a are disengaged. As a result, the driven gear 4 is urged by the tension spring 7 and rotates in the direction of the arrow A, and again meshes 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 about one turn, and the paper is fed by the feed roll 2.
[0017]
The cassette plate 13 is for loading paper and is urged from below by a compression spring (not shown). Reference numeral 14 denotes a seat of the compression spring. Edges 13a and 13b on both sides of the front end of the cassette plate 13 engage with cams 15 and 16 fixed to the shaft 1, and move up and down following the cams 15 and 16. FIG. 1 shows a state in which the cassette plate 13 is pushed downward by the cams 15 and 16.
[0018]
When the paper is fed, the solenoid 11 is energized, the engagement between the claw portion 12a of the movable plate 12 and the engaging portion 10a of the boss 10 is released, the shaft 1 rotates, and the cams 15 and 16 are also arrowed accordingly. Rotate in direction A. Accordingly, the downward urging by the cams 15 and 16 is released, and the cassette plate 13 is raised. When the cassette plate 13 is raised, the circumferential portion of the feed roll 2 is rotated downward from the illustrated state at that time, so that the upper surface of the paper placed on the cassette plate 13 is pressed by the feed roll 2. It is drawn out.
[0019]
A friction member 17 is disposed opposite to the feed roll 2 and the core roll 3, and the paper drawn from the cassette plate 13 is sent between the friction member 17 and the feed roll 2. At this time, since the leading edge of the sheet comes into contact with the friction member 17 at an optimal angle set in advance, the overlapped sheets are loosened 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.
[0020]
When two sheets are fed, the lower sheet comes into contact with the friction member 17 and receives a resistance force, so that only the upper sheet is conveyed to the next feeding step (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. Thus, by pressing the sheet with an appropriate force, the lower sheet continues to receive the resistance force by the friction member 17 until the upper sheet is completely fed out. As a result, even if the upper sheet is pulled, so-called follow-up does not occur.
[0021]
The friction member 17 is held on the base 17a by adhesion or the like. The friction member 17 is made of a material capable of obtaining a high frictional resistance such as rubber or urethane foam rubber. However, it is desirable to select one that is smaller than the frictional resistance around the feed roll 2. The base 17a of the friction member 17 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. Details will be described later with reference to FIG.
[0022]
Next, the structure of the joint part of the feed roll 2, the core roll 3 (roll part) and the shaft 1 will be described. FIG. 2 is a perspective view of the roll portion, and FIG. 3 is a plan view thereof. FIG. 2B shows a front view of the feed roll 2. 2 and 3, the shaft 1 is formed with an engagement groove 19. 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. A claw 20 formed on the core roll 3 engages with the engagement groove 19.
[0023]
Furthermore, a pin 21 is driven into the shaft 1 in the radial direction. The pins 21 are preferably made of metal, and are provided at two locations corresponding to the arrangement positions of the feed rolls 2. An engagement groove 22 is formed in the feed roll 2 at a position corresponding to the pin 21, and the pin 21 engages with the engagement groove 22 when mounted. The pin 21 and the engagement groove 22 can be replaced with a key and a key groove, respectively.
[0024]
The positional relationship between the engagement groove 19 and the pin 21 is set so that the pin 21 is fitted in the engagement groove 22 while the claw 20 is fitted in the engagement groove 19. In such a positional relationship, when the claw 20 is fitted in the engagement groove 19, the feed roll 2 cannot be detached from the shaft 1. Therefore, the following procedure is taken at the time of desorption.
[0025]
With reference to FIG. 4, a procedure for mounting the feed roll 2 on the shaft 1 will be described. First, the claw 20 is bent and removed from the engagement 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. 4B). Subsequently, the feed roll 2 is slid on the shaft 1 to engage the engagement groove 22 with the pin 21, and the core roll 3 is shifted to a position where the claw 20 engages with the engagement groove 19 to complete the procedure. (See FIG. 3). In order to remove the feed roll 2 from the shaft 1, a procedure reverse to this procedure may be executed.
[0026]
Next, the support structure for the friction member 17 will be described. FIG. 5 is a perspective view showing a 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, and a surface parallel to the deleted surface is further formed in the vicinity of the tip portion from the D-cut. Therefore, a part of the circumference is deleted (so-called double D cut). The cross-sectional shape of the support shaft 17b is detailed in FIG. One of the two surfaces in the vicinity of the tip portion formed by the double D cut is made to be on the same plane as the surface in the vicinity of the root portion formed by the D cut.
[0027]
In FIG. 6, a compression spring 25 is disposed between the back surface of the base 17 a and the support plate 18. The repulsive force of the compression spring 25 acts as a force that urges the friction member 17 counterclockwise around the support shaft 17 b in the drawing, and the friction member 17 is pressed against the feed roll 2. A protrusion 17c is provided on the back surface of the base 17a with a clearance C between the base plate 17a and the support plate 18. Even if the friction member 17 is retracted due to the rigidity of the thick paper when, for example, a thick paper having a high rigidity (so-called stiff) is fed by the protrusion 17c, after the protrusion 17c comes into contact, The friction member 17 does not rotate beyond that. Therefore, the clearance between the feed roll 2 and the friction member 17 does not become too large, and double feed can be avoided.
[0028]
Next, the engagement state of the support shaft 17b with the support plate 18 will be described. 7 is a view showing the relationship between the support plate 18 and the support shaft 17b when viewed from the front end side of the support shaft 17b, and is a cross-sectional view at the positions AA and BB in FIG. In the figure, a gap G is secured between the lower surface 23 a of the upper bearing 23 and the upper surface 24 a of the lower bearing 24. 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 formed by double-D cut.
[0029]
From the relationship between the thickness t and the size of the gap G, as shown in FIGS. 7A and 7B, the support shaft 17b passes through the gap G formed by the bearings 23 and 24 of the support plate 18. The bearings 23 and 24 can be fitted. Further, when the support shaft 17b inserted into the upper bearing 23 and the lower bearing 24 is rotated 90 degrees, the state shown in FIG. As can be understood 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 substantially supported by the bearing in the circumferential direction (α + β), the backlash within the bearing is small and high support strength is obtained. In order to remove the support shaft 17b mounted on the support plate 18, the support shaft 17b is rotated, and two surfaces formed by D-cutting are formed as a lower surface 23a of the upper bearing 23 and an upper surface 24a of the lower bearing 24. Just pull it out parallel to the front.
[0030]
【The invention's effect】
As apparent from the above description, according to the first aspect of the present invention, since the support shaft of the friction member can be attached and detached through the open portions of the first and second bearing portions, the friction member can be easily replaced. Since the friction member does not need an extra length for securing the amount of bending as in the above-described conventional device, it can be reduced in size and strength. According to the second aspect of the invention, the amount of retraction of the friction member is restricted, so that double feeding is prevented. Furthermore, according to the third and fourth aspects of the invention, the support shaft can be easily attached to and detached from the bearing by a simple operation of simply rotating the support shaft.
[Brief description of 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.
FIG. 2 is a perspective view of a roll unit according to an 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 shifted.
FIG. 5 is a perspective view of a friction member support.
FIG. 6 is a cross-sectional side view of a friction member support.
FIG. 7 is an enlarged cross-sectional side view of a friction member support portion.
FIG. 8 is a side view and a main part plan view of a conventional paper feeding device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Shaft, 2 ... Feed roll, 3 ... Core roll, 4 ... Drive gear, 5 ... Drive gear, 11 ... Solenoid, 13 ... Cassette plate, 15, 16 ... Cam, 17 ... Friction member, 17a ... Support shaft, 17b ... Base

Claims (4)

In a paper feeding device having a feed roll and a friction member that is supported by a support shaft parallel to the axis of the feed roll and arranged to face the feed roll,
A first plane formed on a support shaft of the friction member and having a predetermined length parallel to the support shaft and in the axial direction of the support shaft;
A second plane formed on a support shaft of the friction member, parallel to the first plane and having a predetermined length in the axial direction of the support shaft;
In order to support the support shaft, the first bearing portion disposed corresponding to the first plane, and a bearing comprising a second bearing portion disposed corresponding to the second plane,
Each of the first bearing portion and the second bearing portion has a partial inner periphery for supporting the support shaft, and when the first bearing portion and the second bearing portion are viewed in an axial direction, The first inner bearing part and the second bearing part form an open part having a gap larger than at least the distance between the first plane and the second plane. A paper feeding device characterized by being made. An elastic body that biases the friction member toward the feed roll;
2. The sheet feeding device according to claim 1, further comprising a retraction restricting unit for a friction member for restricting an amount of retraction of the friction member toward the elastic body. A method for removing a sheet feeding device according to claim 1 or 2, wherein
Rotating the support shaft so that the first plane and the second plane are parallel to the surfaces of the first bearing section and the second bearing section defining the open section,
A method for removing a rolling device, wherein the support shaft is pulled out from the bearing portion through the open portion. A method for assembling a sheet feeding device according to claim 1 or 2,
Aligning the support shaft such that the first plane and the second plane are parallel to the surfaces of the first bearing section and the second bearing section defining the open section;
The support shaft is inserted into the bearing portion through the open portion,
The support shaft is rotated in the bearing so that the first and second planes are not parallel to the surfaces of the first and second bearing portions, and the friction member is moved by the feed roll. A method of assembling a paper feeder for a sheet feeding device, wherein

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