JP2916044B2 - Sheet material feeding device - 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 apparatus used for an image forming apparatus such as a copying machine, a printer, and a facsimile.

[0002]

2. Description of the Related Art Generally, in a sheet feeding apparatus of an image forming apparatus such as a copying machine, a sheet material such as a transfer sheet and a photosensitive sheet is transferred to a sheet loading table (movable table) in a cassette 100 shown in FIG. A large number of sheets are stacked on the sheet) 101, and sheet materials are separated and fed one by one from the sheet material stacking base plate 101 one by one toward a next process by a sheet feeding means such as a sheet feeding roller.

However, in the case of such a sheet material feeding device, in the cassette 100 as a sheet material storage unit, the leading end portion of the sheet material loading base plate 101 constantly urged upward by the urging spring 102. Alternatively, the top end of the sheet material stacked on the sheet material stacking base plate 101 is pushed down to the highest position, and the sheet material is stabilized in a state of being in contact with the separating means (separating claw) 103 or the sheet feeding means. Therefore, the sheet material is replenished and loaded into the cassette 100 while being pressed down against the urging spring 1012 of the sheet material loading base plate 101 and while the leading end of the replenishing sheet material is flanked by the separating means or the paper feeding means. To be performed, the sheet material cassette 100
There was a drawback that the supply to the inside was poor.

In order to solve such a drawback, a sheet feeding apparatus shown in FIG. 20 has recently been proposed (see Japanese Utility Model Publication No. 53-46020).

In this sheet feeding apparatus, when a sheet loading table 106 is pushed down against a cassette (stocker) 105 against a biasing spring 107, the sheet loading table 106 is engaged with a predetermined position. Locking means 109 (which comprises a pin 110 provided on the sheet material loading base plate 106 and a lock lever 112 provided on the side plate 111 of the cassette 105) for stopping the sheet material is provided. When mounting on an image forming apparatus main body (not shown),
Release means 113 for releasing the locking means 109 (the lock lever 112 thereof) is provided on the image forming apparatus main body side.

In FIG. 20, reference numeral 106A denotes a support shaft of the sheet material loading base plate 106, and reference numeral 112A denotes a lock lever 1.
Reference numeral 115 denotes an urging spring of the lock lever 12,
Reference numeral 116 denotes a separation claw, and reference numeral 117 denotes a paper feed roller.

[0007]

However, in the case of the above-mentioned sheet feeding apparatus (the proposed technique shown in FIG. 20), when the cassette 105 is mounted on the image forming apparatus main body, the locking means 109 is released by the releasing means 113. When released
Due to the action of the biasing spring 107, the sheet loading base plate 106 jumps up violently, giving the user unnecessary anxiety, and also causing a shift in the damaged loading position of the sheet due to collision with the separating means 116 or the paper feeding means 117. There may be a problem that a paper jam or a trouble due to an impact given to the main body of the image forming apparatus is caused. This is more remarkable when the sheet material is mounted in a state where the amount of the sheet material is smaller than the capacity of the cassette 105, such as when clearing the jam or when temporarily using a small amount of the sheet material that is not frequently used.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and has been made in consideration of the above-mentioned circumstances. The movable base plate when the locking means for locking the movable base plate on which the sheet material is loaded is released by the release means is released. It is an object of the present invention to provide a sheet material feeding device capable of suppressing a rapid rise of the sheet material.

[0009]

According to the present invention, there is provided a movable base plate for stacking a sheet material, a movable base plate urging means for feeding the movable base plate to the sheet material, and the movable base plate being movable with the movable base plate. A sheet material cassette having locking means for locking the movable base plate at a predetermined position when pressed down against the plate plate urging means; and feeding the sheet material contained in the sheet material cassette. A sheet material feeder, and releasing means for releasing an engagement state between the movable base plate and the locking means when the sheet material cassette is mounted on the sheet material feeder. Related.

[0010] In order to achieve the above object, the present invention provides a buffer means for buffering a sudden rise operation of the movable base plate when the engagement state between the movable base plate and the locking means is released by the release means. And the buffer means comprises:
A buffer member that engages with the movable base plate and provides resistance when the movable base plate is lifted, and that the buffer member is engaged with the movable base plate during mounting of the sheet material cassette, and When the mounting of the sheet material cassette is completed, the sheet cassette is disposed at a position where the engagement with the movable base plate is released. Alternatively, according to the present invention, with the operation of taking out the sheet material cassette from the cassette mounting portion, there is provided a plate pressing unit for moving the movable plate down to the predetermined position against the movable plate urging unit. In the sheet feeding apparatus provided, the engagement between the cushioning member and the movable base plate and the engagement between the base plate pressing means and the movable base plate occur at different times. And Further, the buffer member is retracted to a position where it does not engage with the movable base plate when the sheet material cassette is mounted on the cassette mounting portion and feeds paper. Further, when the movable base plate and the buffer member are engaged with each other, a resistance reducing means for reducing the resistance in the mounting / removing direction of the sheet material cassette to be smaller than the resistance in the rising direction of the movable base plate is provided. It is characterized by.

[0011]

According to the above structure, when the movable base plate and the locking means are disengaged from each other and the movable base plate rapidly rises by the action of the movable base plate urging means, the sudden rising operation of the movable base plate is buffered by the buffer means. Is done.

As a result, the collision with the separating means and the paper feeding means is relieved, and the replenished sheet material is not damaged, and the paper jam due to the displacement of the stacking position does not occur. In addition, when the mounting of the sheet material cassette is completed, the movable base plate and the buffer member do not engage with each other and do not receive resistance when ascending, so that the sheet materials stacked on the movable base plate can be smoothly pushed up and supplied to the paper feeding means. Further, engagement between the cushioning member and the movable base plate,
Since the engagement between the base plate pressing means and the movable base plate occurs at different times, the movable base plate can be smoothly moved down. Further, the resistance at the time of attaching and detaching the sheet material cassette is reduced by the resistance reducing means.

[0013]

[0014]

Embodiments of the present invention will be described below with reference to the drawings. <Embodiment 1> FIGS. 1 and 2 show the overall configuration of a sheet material feeder of a sheet material feeding apparatus according to Embodiment 1 of the present invention.
3 and 4 show the overall configuration of a sheet material cassette of the sheet feeding apparatus.

First, the configuration of the sheet material feeder 30 as a cassette mounting portion to which a sheet material cassette is mounted will be described with reference to FIGS.

In the figure, reference numeral 31 denotes an upper plate of a feeder, reference numerals 32L and 32R denote bases long in the front-rear direction attached to the left side and right side of the upper surface plate 31 in parallel with each other, and reference numeral 33.
Is a lower plate of the feeder.

The lower surface plate 33 of the feeder is provided with an unlocking piece 33A at the front end.

The lower surface of the feeder upper plate 31, the upper surface of the feeder lower plate 33, and the inner surfaces of the left and right pedestals 32L and 32R,
A sheet material cassette storage space C (FIG. 1) is configured.

Reference numeral 35 denotes a sheet feeding roller, and reference numeral 36 denotes a sheet feeding roller.
Denotes a sheet material conveying roller.

The sheet feeding roller 35 is a roller (D-shaped cut roller) having a partially circular shape in a side surface or a cross section.

Sheet material feed roller 35 and transport roller 36
Are substantially parallel to each other, the transport roller 36 is located on the tip side of the feeder upper plate 31, and the feed roller 35 is located further upstream than the feed roller 35 in the sheet material feeding direction.

Reference numerals 42, 42 (one not shown) denote sheet material cassette insertion / reception guide grooves symmetrically provided on the inner surfaces of the left and right pedestals 32L, 32R along the longitudinal direction.
43 (one not shown) is also the left and right pedestals 32L, 32
The cam grooves are provided symmetrically on each inner surface of the R, and include a front inclined portion 43A, a substantially horizontal portion 43B, and a rear inclined portion 43C.

Reference numerals 46, 46 (one not shown) are friction members provided symmetrically protruding from the inner surfaces of the same left and right pedestals 32L, 32R, and are located behind the cam grooves 43, 43. . Inclined surfaces 46A, 46A are provided in front and rear of the friction member 46, and are configured to smoothly connect to the inner surfaces of the pedestals 32L, 32R.

Reference numeral G in FIG. 1 denotes a gear train for transmitting rotation to the sheet material feeding roller 35 and the conveying roller 36.

Next, the structure of the sheet material cassette 50 will be described with reference to FIGS.

In the figure, reference numeral 51 denotes a cassette body case having a flat rectangular shape whose upper surface is open, and reference numerals 51A, 51B,
Reference numerals 51C, 51D, and 51E denote a front wall, a left wall, a right wall, a rear wall, and a bottom plate of the cassette body case 51.

Reference numeral 52 denotes a handle provided outside the cassette main body case 51, and reference numerals 54L and 54R denote elongated flanges extending outward along the upper end longitudinal direction of the left and right side walls 51B and 51C of the cassette main body case 51. is there.

Reference numeral 55 denotes a movable base plate accommodated in the cassette body case 51, which is urged upward by a pressing spring 62 with the rear end 55A as a pivot point. At the front end of the rotary base plate 55, a base plate locking portion 55B is provided.
The base plate locking portion 55B is connected to the front wall 5 via locking portion groove notches 53 provided on the front wall 51A of the cassette body case 51.
It protrudes from the back side of 1A. The sheet material P is stacked on the movable base plate 55 and stored in the cassette body case 51.

Reference numeral 59 denotes a pressing shaft engaged with the movable base plate 55. The pressing shaft 59 is provided at both left and right ends 59L and 59R.
Are symmetrically provided on the surfaces of the left and right side walls 51B, 51C of the cassette body case 51, respectively.
The left and right end portions 59L, 59R protrude outside the left and right side walls 51B, 51C. Both end surfaces of the pressing shaft 59 are substantially spherical.

Reference numerals 63, 63 designate a cassette body case 51.
Are provided on the left and right side walls 51B and 51C, and reference numerals 63A and 63A are separation claws. The separation claw levers 63, 63 are rotatable up and down with their rear ends 63B, 63B serving as fulcrums, and their front ends 63C, 63C are provided on the front wall 51A of the cassette body case 51.
5, 65. Reference numerals 68, 68 are sheet material conveying rollers.

FIG. 5 shows a detailed configuration of the lock portion of the movable base plate 55.

Reference numeral 57 denotes a lock claw for holding the movable base plate 55 at a predetermined position. Reference numeral 61 denotes a rib provided on the back surface of the front wall 51A of the cassette body case 51,
It is located between the locking slots 53 provided in the front wall 51A.

The locking claw 57 is supported by a tension coil spring 58 by a support shaft 5 provided on the front end side of the movable base plate 55.
7A is urged counterclockwise around the lock claw 5A.
The rotation of the front end 57B is restricted by the lower end 57B abutting against the rib 61 from below.

The movable base plate 55 includes the cassette main body case 51.
The locking portion 55B protruding from the back surface of the front wall 51A
By contacting the tip 57B of the lock claw 57 from below, it is held at a predetermined position.

On the other hand, the unlocking arm 57C projects below the bottom plate 51E of the cassette body case 51,
E is covered by a protective cover 64 provided.

Behind the protective cover 64, the opening 6 into which the unlocking piece 33A provided on the feeder lower plate 33 fits.
4A is provided.

FIG. 6 shows the positional relationship between the base plate pressing shaft 59 of the sheet material cassette 50, the cam groove 43 and the friction member 46 of the sheet material feeder 30. Both ends 59L and 59R (one not shown) of the push-down shaft 59 are configured such that their shaft peripheral surfaces are engaged with the cam groove 43, and the both end surfaces are in contact with the friction member 46 to slide. It is.

FIGS. 7, 8, 9 and 10 successively show the operation of the main part when the sheet cassette 50 is detached from the sheet feeder 30. FIG.

When the sheet material cassette 50 is mounted on the sheet material feeder 30, the pressing shaft 59 is separated from the cam grooves 43. The movable base plate 55 is pushed upward by a pressing spring 62, and the uppermost sheet material or the corner on the tip side of the base plate 55 is in contact with the separation claw 63A. On the other hand, the unlocking arm 57C is provided with an unlocking piece 33A provided on the feeder lower plate 33 of the sheet material feeder 30.
, And the lock claw 57 is held at the retracted position (the state of FIG. 7).

The sheet cassette 50 is taken out of the sheet feeder 30 by a handle 52 on the front side of the cassette.
7 is pulled and moved in the direction of arrow X in FIG.

At the initial stage of the removal movement of the sheet material cassette 50, the lock claw 57 is separated from the unlocking piece 33A as the sheet material cassette 50 is pulled out, and is counterclockwise by the urging force of the tension coil spring 58. It rotates and is held in the locked position by contacting the rib 61 (the state of FIG. 8).

Further pulling-out movement of the sheet material cassette 50 causes the left and right side walls 51B, 5B of the sheet material cassette 50 to move.
Left and right end portions 5 of push shaft 59 projecting outward from 1C
9L and 59R are respectively engaged with the rear inclined portions 43C and 43C of the cam groove 43 provided on the inner surface side of the left and right pedestals 32L and 32R of the sheet material feeder 30, and the pressing shaft is moved by the subsequent pulling movement force of the sheet material cassette 50. Left and right ends 59 of 59
L, 50R are pressed downward by the rear inclined portions 43C, 43C of the cam groove 43, and the pressing shaft 59 is moved from the upper end side starting point to the lower end along the oblique vertical grooves 60, 60 with which the pressing shaft 59 is engaged. Descends to the side end point. With the downward movement of the pressing shaft 59, the movable base plate 55 rotates downward with the rear end portion 55A as a fulcrum (the state of FIG. 9).

With the subsequent pull-out movement of the sheet material cassette 50, the movable base plate 55 is lowered to the lowest position by the cam grooves 43, 43, and the locking portion 55 provided at the tip of the movable base plate 55
B engages with the lock claw 57 after pushing over the lock claw 57 and thereby engaging the movable claw 57 with the sheet material cassette 50.
Is locked near the bottom of the sheet feeder 3
It is removed from 0 (the state of FIG. 10).

When the movable base plate 55 is locked, the unlocking arm 57C of the lock claw 57 is
The bottom cover 51E is covered with a protective cover 64 provided so as not to be easily touched from outside. Further, since the other portion of the lock claw 57 is almost completely accommodated in the sheet material cassette 50, the lock is not released unnecessarily during the normal sheet material supply operation.

The sheet material P is loaded and stored in the sheet material cassette 50 by removing the sheet material cassette 50 from the sheet material feeder 30 as described above.
From the opening on the top surface. In the state shown in FIG. 10 in which the sheet material cassette 50 is removed from the sheet material feeder 30, the movable base plate 55 in the cassette body case 51 is locked near the bottom plate 51 of the cassette body case 51 as described above. Further, the separation claws 63A, 63A are arranged such that the distal ends 63C, 63C of the levers 63, 63 provided with the separation claws 63A, 63C ride on one side of the separation claw opening windows 65, 65 provided on the front wall 51A of the cassette body case 51. Since it is received and its rotation downward is regulated, it is held above the upper opening in the cassette body case 51. Therefore, the tip side of the movable base plate 55 and the separation claws 63A,
Since the distance between the sheet material P and the sheet material P is kept large, the operation of loading and storing the sheet material P in the cassette body case 51 can be performed easily and quickly.

The mounting of the sheet material cassette 50 on the sheet material feeder 30 is performed by the upper plate 3 of the sheet material feeder 30.
1, lower surface of feeder lower plate 33, left and right pedestals 32
The rear wall 51D of the sheet cassette 50 from the front of the sheet feeder 30 with respect to the sheet cassette storage space C (FIG. 1) formed by the inner surfaces of the L and 32R.
In addition, the longitudinally extending guide grooves 4 provided on the inner surfaces of the pedestals 32L, 32R of the sheet material feeder 30 along the longitudinal direction have elongated flanges 54L, 54R on the left and right sides of the cassette, respectively.
Then, they are pushed into the fittings 2 and 42 (in the direction of arrow Y in FIG. 10).

The operation of each part when the sheet material cassette 50 is mounted is the reverse of the operation when the cassette is pulled out. That is, at the time immediately before the sheet material cassette 50 is sufficiently pushed into the sheet material feeder 30 and moved to be properly mounted,
Left and right end portions 59L, 59 of the pressing shaft 59 protruding outward from the left and right side walls 51B, 51C of the sheet material cassette 50.
R is the left and right pedestals 32 of the sheet material feeder 30, respectively.
L, 32R engages with the front inclined portions 43A, 43A of the cam grooves 43, 43 provided on the inner surface side, and gets over the cam grooves 43, 43.

By the subsequent pushing movement of the sheet material cassette 50, the unlocking arm 57C of the locking claw 57 comes into contact with the unlocking piece 33A, and the locking claw 57 rotates clockwise to release the lock. With this, the sheet material cassette 5
The base plate 55 of 0 is rotated upward by the urging force of the pressing spring 62 with the rear side 55A of the base plate as a fulcrum. When the lock is released, the left and right end surfaces of the pressing shaft 59 are in contact with the friction members 46, 46. Because it is engaged (the dashed line in FIG. 8),
The pressing shaft 59 receives sliding resistance from the friction members 46, 46, and as a result, the movable base plate 55 is slowly rotated upward. The rotation of the rotation base plate 555 is such that the uppermost sheet material or the corner portion on the tip side of the movable base plate 55 has the separation claw 63A,
It stops when it comes into contact with 63A.

Then, when the sheet cassette 50 is sufficiently pushed into a proper mounting state, the sheet conveying roller 68 of the sheet cassette 50 is brought into contact with the front surface of the sheet conveying roller 35 of the sheet feeder 30. Become.

Until immediately before the sheet material cassette 50 is sufficiently pushed into the sheet material feeder 30 to be mounted properly, the movable base plate 55 is held by the lock claws 57 near the bottom plate 51E of the cassette body case 51. The stacked sheet material P on the movable base plate 55 is also accommodated in the cassette body case 51 in a horizontal posture. Further, as described above, the sheet material feeding roller 35 disposed on the upper plate 31 side of the sheet material feeder 30 is a cutout roller (D-shaped cut roller), and the cutout side 35A is always in a downward rotation angle posture. To stop rotation. For this reason, in the movement process accompanying the attachment / detachment of the sheet material cassette 50, the upper surface of the uppermost sheet material of the stored stacked sheet materials P in the cassette body case 51 is sufficiently lowered downward from the downwardly open circle side 35A of the sheet material feeding roller 35. In a separated relationship, the sheet material feeder 3
There is no interference with the feeding roller 35 on the 0 side.

In a state where the sheet material cassette 50 is mounted at a proper position of the sheet material feeder 30, when a sheet supply start signal is input on the image forming apparatus side, the gear train G, the clutch (not shown) and the clutch (not shown) The sheet feeding roller 35 makes one rotation by the action of the electromagnetic solenoid, and the uppermost sheet is separated one by separation claws 63A, 63A and is fed out toward the front wall 51A of the sheet cassette 50, and the sheet material feeder 30 side Sheet material transport roller 36
The sheet is introduced from below into a nip formed by the sheet material conveying roller 68 on the side of the sheet material cassette 50, gripped and conveyed upward, and fed into the image forming apparatus main body. As the consumption of the stacked storage sheet materials P in the sheet material cassette 50 decreases, the movable base plate 55 is sequentially lifted and rotated by the urging force of the pressing spring 62.

Thus, each time the sheet feed roller 36 on the side of the sheet feeder 30 is driven one revolution, the sheet cassette 5 mounted on the sheet feeder 30 is rotated.
The stacked storage sheet material in the area No. 0 is fed to the image forming apparatus main body side for one sheet, and image formation on the fed sheet material is sequentially performed.

The sheet feeding apparatus of the present invention is configured as described above. In the process of mounting the sheet cassette 50 on the main body of the image forming apparatus, when the lock of the movable base plate 55 is released, the pressing shaft is already pressed. Since both left and right end surfaces of the contact member 59 are in contact with the friction members 46, the lifting of the pressing shaft 59 receives sliding resistance from the friction members 46. Therefore, when the lock is released, the rotating base plate 55 does not jump up suddenly, and the conventional easy and quick sheet material replenishing property can be achieved without affecting the image forming apparatus main body and the sheet material with good operability. Can be realized.

In this embodiment, the friction brake is used as the buffer means. However, the technical idea of the present invention is to buffer the upward movement of the movable base plate 55 when the lock is released. It goes without saying that a member, a torque limiter, an air damper, an electromagnetic brake or the like may be used. <Embodiment 2> This embodiment will be described with reference to FIG.

In the present embodiment, the friction member 46 is provided at a position different from the moving range of the base plate pressing shaft 59 in the state in which the sheet material cassette 50 is mounted at the regular position of the sheet material feeder 30 with the sheet feeding. I have. <Embodiment 3> FIG.

In this embodiment, the friction member 46 is provided so as to be rotatable in a direction indicated by an arrow in the drawing with a rotation support shaft 46D provided on the lower side thereof as a fulcrum. Reference numeral 71 denotes the friction member 46,
Reference numeral 48 denotes an electromagnetic solenoid for rotating and holding the friction member 46 at a retracted position separated from the base plate pressing shaft 59 in a compression coil spring that urges the base plate pressing shaft 59 in a contacting direction.

The electromagnetic solenoid 48 rotates the friction member 46 to the retracted position against the urging force of the compression coil spring 71 in response to the feed start signal from the image forming apparatus main body, and holds the same. Is controlled by the control means 49 so as to release the holding of the friction member 46 in response to the sheet feeding end signal of the above. The friction member 46 whose holding is released is
The compression coil spring 71 rotates to a buffer position where the compression coil spring 71 comes into contact with the depression of the base plate.

This embodiment is configured as described above.
At the time of sheet feeding, both end surfaces of the pressing shaft 59 and the friction members 46, 46 of the pedestals 32L, 32R of the sheet material feeder 30 are separated from each other. 46, 46 do not interfere with the operation of the movable base plate 55. For this reason, the friction members 46, 46 do not affect the sheet feeding pressure for pressing the sheet material P against the sheet material feeding roller 35, and the same effects as in the first embodiment can be obtained while maintaining a stable sheet feeding pressure. .

The technical idea of this embodiment is to eliminate the influence of the buffer means 46 on the paper feed pressure at least at the time of paper feed. For example, the ON / OFF of a cassette mounting completion signal by a sensor is used. The above control may be performed, or the retracting rotation driving force of the friction member 46 may be obtained from the driving source of the sheet feeding roller 35, and the operation of the friction member 46 may be linked with the operation of the sheet feeding roller 35. Needless to say, the base plate pressing shaft 59 may be retracted. <Embodiment 4> This embodiment will be described with reference to FIG.

In this embodiment, the sheet material feeder 30
The friction members 46, 46 of the pedestals 32L, 32R are provided at different positions in the attachment / detachment direction of the cam grooves 43, 43 and the sheet material cassette 50.

This embodiment is configured as described above.
In attaching and detaching the sheet material cassette 50, the base plate pressing shaft 59 of the sheet material cassette 50 is
There is no simultaneous contact with both 3 and 43. Therefore, in the removal operation of the sheet material cassette 50, the sliding resistance by the friction members 46, 46 and the base plate pressing resistance by the cam grooves 43, 43 are not simultaneously applied, and the maximum value of the removal resistance of the sheet material cassette 50 is reduced. By suppressing, the same effect as that of the first embodiment can be obtained while realizing good operability.

The technical idea of the present embodiment is that the sliding resistance by the friction members 46, 46 and the pressing resistance of the base plate by the cam grooves 43, 43 act at different times in the removal operation of the sheet material cassette 50. , For example, friction members 46, 46
May be provided so as to be retractable so that the friction members 46 and 46 are retracted to a position where they do not interfere with the rotating base plate 55 during the pressing operation of the base plate in the removing operation of the sheet material cassette 50. <Embodiment 5> This embodiment will be described with reference to FIG.

FIG. 12 is a perspective view of the end portion of the base plate pressing shaft 59 of the sheet cassette 50.

Reference numeral 59A denotes a crown-shaped roller provided on the end surface of the pressing shaft 59. The roller 59A is provided so as to be movable about a rotation shaft 59B provided substantially perpendicularly to the mounting / removing direction of the sheet material cassette 50. The base plate pressing shaft 59 is locked so that the rotation base plate 55 cannot rotate.

According to the present embodiment, the sliding opposition between the pressing shaft 59 and the friction member 46 in the mounting and dismounting direction of the sheet material cassette 50 in the mounting and dismounting of the sheet material cassette 50 is reduced by the rotation of the roller 59A. On the other hand, the lifting of the rotary base plate 5 due to the release of the lock is substantially parallel to the axial direction of the movable support shaft 59B of the roller 59A, and the sliding resistance is not reduced by the rotation of the roller 59A. <Embodiment 6> This embodiment will be described with reference to FIGS.

FIG. 13 is a perspective view of an end portion of the base plate pressing shaft 59, and FIG. 14 is a plan view showing an engagement state between the base plate pressing shaft 59 and the friction member 46.

The base plate pressing shaft 59 in this embodiment is non-rotatably locked to the rotary base plate 55, and its both end faces are provided with elongated ribs 50C substantially parallel to the sheet material cassette attaching / detaching direction. On the other hand, the friction member 46 is formed of a flexible body. The positional relationship between the friction member 46 and the base plate pressing shaft 59 is, as shown in FIG.
C is configured to abut while deforming the friction member 46.

According to the present embodiment, the sliding between the pressing shaft 59 and the friction member 46 receives the frictional resistance and the deformation resistance for deforming the frictional member 46. The deformation area 72 of the member 46 is smaller than the deformation area 73 in sliding in the direction in which the movable base plate 55 rises. Therefore, the resistance in the sliding is smaller in the mounting / removing direction of the sheet material cassette 50 than in the moving direction of the movable base plate 55.

This embodiment is configured as described above.
It is possible to sufficiently reduce the mounting / detaching resistance of the sheet material cassette 50 while sufficiently obtaining the braking force against the rise of the movable base plate 55, and obtain the same effect as that of the first embodiment while realizing good operability. . <Embodiment 7> This embodiment will be described with reference to FIG.

FIG. 15 is a longitudinal sectional view of the friction member 46.
On the surface of the friction member 46, a flexible body 46C is disposed at a predetermined density with a diagonally downward direction as shown in the figure. <Embodiment 8> This embodiment will be described with reference to FIG.

FIG. 16 shows that the friction member 46 is made of a flexible material.
The surface has an uneven shape composed of a plurality of diagonally downward slopes and a horizontal plane as shown in the figure.

In the case of the seventh and eighth embodiments, the sliding of the base plate pressing shaft 59 and the friction member 46 causes the pressing shaft 5 to slide.
The sliding resistance at the time of upward movement of 9 is larger than the sliding resistance in other directions. <Embodiment 9> This embodiment will be described with reference to FIGS.

FIG. 17 is a cross-sectional view of a main part of a resistance means for giving resistance to the rotation of the flexible base plate 55 of the sheet material cassette 50, and FIG. 18 is a perspective view.

Reference numeral 55 denotes a friction piece symmetrically provided on the side surface of the flexible base plate 55 of the sheet material cassette 50, and has a curved surface curved vertically. Reference numeral 46 denotes a friction member symmetrically provided near the left and right side walls 51B and 51C of the sheet cassette 50. The movable support is provided by a spring (not shown) using a rotation support shaft 46A provided near the periphery thereof as a rotation fulcrum. The plate 55 is urged in a direction away from the friction piece 55C.

Reference numeral 46 denotes a rib provided on the upper portion of the friction member 46, and the left and right side walls 51B, 5B of the sheet material cassette 50.
It protrudes outside from a friction member opening window 66 provided in 1C. Reference numeral 47 denotes the left and right pedestals 32 of the sheet material feeder 30.
This is a friction member operation cam provided symmetrically on the inner surface of L, 32R.

When the sheet material cassette 50 is mounted on the feeder 30, the rib 46B of the friction member 46 engages with the friction member operation cam 47 of the pedestals 32L, 32R of the feeder 30 immediately before the movable base plate 55 is unlocked. At this time, the friction member 46 rotates around the rotation support shaft 46A as a fulcrum and comes into contact with the friction piece 55C of the movable base plate 55.

With the subsequent pushing movement of the sheet material cassette 50, the lock of the movable base plate 55 is released, and the movable base plate 55 is released.
Slowly rises while receiving the sliding resistance of the friction member 46. Furthermore, when the sheet material cassette 50 is sufficiently pushed into a normal mounting state, the ribs 46B of the friction member 46 ride over the friction member operation cams 47 of the pedestals 32L and 32R of the sheet material feeder 30 and are separated therefrom.
Are the friction pieces 5 of the movable base plate 55 by the urging force of a spring (not shown).
Separate from 5C.

This embodiment is configured as described above.
The sliding between the friction member operation cam 47 and the friction member 46 when the sheet material cassette 50 is attached and detached is performed via a rib 46C having a relatively small sliding resistance, and the members constituting the sheet material cassette 50 and the sheet material feeder 30 are provided. And friction member 46
There is no sliding in the cassette attaching / detaching direction. Therefore, the same effect as that of the first embodiment can be obtained while obtaining a sufficient braking force against the elevation of the rotating base plate 55 and at the same time, realizing good operability.

Further, it is possible to realize a constant cassette attaching / detaching resistance irrespective of the friction coefficient of the friction member 46, and it is possible to select an optimal friction member without affecting the cassette attaching / detaching resistance regardless of the apparatus. it can.

[0080]

As described above, in the sheet feeding apparatus according to the present invention, when the locking means for locking the movable base plate on which the sheet material is loaded is fixed to the predetermined position, the movable base plate is released by the releasing means. Since the movable base plate which rises rapidly by the action of the base plate urging means is buffered by the buffer means, the collision with the separating means and the paper feeding means is reduced. For this reason, the replenished sheet material is not damaged, and paper jam due to a shift in the stacking position does not occur. Further, when the sheet material cassette is completely mounted, the movable base plate that is not engaged with the buffer member does not receive resistance from the buffer member when ascending, so that the sheet material loaded on the movable base plate can be removed. Push-up supply to the paper feeding means can be performed smoothly. In addition, since the engagement between the cushioning member and the movable base plate and the engagement between the base plate pressing means and the movable base plate occur at different times, the movable base plate can be smoothly moved down, and a favorable movement can be achieved. Operability is realized. In addition, good operability is realized by reducing the resistance at the time of attaching and detaching the sheet material cassette by the resistance reducing means.

[Brief description of the drawings]

FIG. 1 is an external perspective view illustrating an overall configuration of a sheet material feeder of a sheet material feeding device according to a first embodiment of the present invention.

FIG. 2 is a vertical side view showing the entire configuration of the sheet material feeder.

FIG. 3 is an external perspective view showing the overall configuration of the sheet material cassette.

FIG. 4 is a vertical sectional side view showing the entire configuration of the sheet material cassette.

FIG. 5 is a vertical sectional side view showing a detailed configuration of a lock portion of a movable base plate of the sheet material cassette.

FIG. 6 is a vertical sectional side view showing a positional relationship between a base plate pressing shaft of the sheet material cassette, a cam groove of a sheet material feeder, and a friction member.

FIG. 7 is a vertical sectional side view of an essential part for explaining an operation when the sheet material cassette is removed from the sheet material feeder.

FIG. 8 is a vertical sectional side view of an essential part for explaining an operation when removing the sheet material cassette from the sheet material feeder.

FIG. 9 is a vertical sectional side view of an essential part for explaining an operation when removing the sheet material cassette from the sheet material feeder.

FIG. 10 is a vertical sectional side view of a main part for explaining an operation when removing the sheet material cassette from the sheet material feeder.

FIG. 11 is a vertical sectional side view showing another configuration example (Example 3) of the friction member provided in the sheet material feeder.

FIG. 12 is a perspective view showing another configuration example (embodiment 5) of the bed plate pressing shaft provided in the sheet material cassette.

FIG. 13 is a perspective view showing another example (sixth embodiment) of a base plate pressing shaft provided in the sheet material cassette.

FIG. 14 is a plan view showing an engagement state between the pressing shaft and a friction member.

FIG. 15 is a vertical sectional side view showing another configuration example (Example 7) of the friction member provided in the sheet material feeder.

FIG. 16 is a longitudinal sectional side view showing another configuration example (Example 8) of the friction member provided in the sheet material feeder.

FIG. 17 is a longitudinal sectional side view showing a configuration example (embodiment 9) of a resistance means for giving resistance to the turning operation of the movable base plate of the sheet material cassette.

FIG. 18 is a perspective view of the resistance means.

FIG. 19 is a longitudinal sectional side view showing a configuration of a sheet material cassette of a conventional example (normal structure).

FIG. 20 is a vertical sectional side view showing a configuration of a sheet material feeding device of a conventional example (proposed technology).

[Explanation of symbols]

 Reference Signs List 30 sheet material feeder 33A unlocking piece (release means) 35 sheet material feeding roller (sheet material feeding means) 46 friction member (buffer means) 50 sheet material cassette 55 rotating base plate 57 locking claw (locking means) 62 Push-up spring (rotating bed plate urging means) P Sheet material

Claims (11)

(57) [Claims] 1. A movable base plate for stacking sheet materials,
Movable plate urging means for urging the movable plate upward, and when the movable plate is depressed against the urging force of the movable plate urging means, the movable plate is pressed by a predetermined amount. A sheet material cassette having locking means for locking the sheet material cassette; a cassette mounting portion to which the sheet material cassette can be mounted; and the movable base plate of the sheet material cassette provided in the cassette mounting portion and mounted. Sheet material feeding means for feeding the sheet material loaded on the cassette, and releasing means for releasing the engagement between the movable base plate and the locking means when the sheet material cassette is pushed into the cassette mounting portion. And a buffer means for buffering a sudden rising operation of the movable base plate when the engagement state between the movable base plate and the locking means is released by the release means. The buffer means Has a cushioning member which gives resistance during rising of the movable base plate engages with the movable base plate, the cushioning member,
A sheet material feeding device is provided at a position where the sheet material cassette is engaged with the movable base plate during the mounting, and at a position where the engagement with the movable base plate is released when the mounting of the sheet material cassette is completed. Feeder. 2. The sheet feeding device according to claim 1, wherein the buffering member has a friction member for engaging the movable base plate to provide sliding resistance. 3. A movable base plate for stacking sheet materials,
Movable plate urging means for urging the movable plate upward, and when the movable plate is depressed against the urging force of the movable plate urging means, the movable plate is pressed by a predetermined amount. A sheet material cassette having locking means for locking the sheet material cassette; a cassette mounting portion to which the sheet material cassette can be mounted; and the movable base plate of the sheet material cassette provided in the cassette mounting portion and mounted. Sheet material feeding means for feeding the sheet material loaded on the cassette, and releasing means for releasing the engagement between the movable base plate and the locking means when the sheet material cassette is pushed into the cassette mounting portion. Buffer means for buffering a sudden rise of the movable base plate when the engagement state between the movable base plate and the locking means is released by the release means; and Take out A plate pressing unit for lowering the movable plate to the predetermined position against the movable plate urging unit, according to a work. A buffer member that engages with the base plate to provide resistance when the movable base plate is lifted, and that engages the buffer member with the movable base plate and engages with the base plate pressing means and the movable base plate. A sheet feeding device characterized in that joining occurs at another time. 4. The base plate pressing means includes a cam provided on the cassette mounting portion, a base plate pressing shaft provided on the movable base plate, and sliding on the cam to press down the movable base plate. The sheet feeding device according to claim 3, comprising: 5. The sheet material feeding device according to claim 4, wherein said buffer means applies resistance when said movable base plate is lifted by engaging said base plate pressing shaft. 6. A movable base plate for stacking sheet materials,
Movable plate urging means for urging the movable plate upward, and when the movable plate is depressed against the urging force of the movable plate urging means, the movable plate is pressed by a predetermined amount. A sheet material cassette having locking means for locking the sheet material cassette; a cassette mounting portion to which the sheet material cassette can be mounted; and the movable base plate of the sheet material cassette provided in the cassette mounting portion and mounted. Sheet material feeding means for feeding the sheet material loaded on the cassette, and releasing means for releasing the engagement between the movable base plate and the locking means when the sheet material cassette is pushed into the cassette mounting portion. And a buffer means for buffering a sudden rising operation of the movable base plate when the engagement state between the movable base plate and the locking means is released by the release means. The buffer means A buffer member that engages with the movable base plate and provides resistance when the movable base plate is lifted, wherein the buffer member is connected to the movable base plate when the sheet material cassette is mounted on the cassette mounting portion and fed. A sheet feeding device retracted to a position where it is not engaged. 7. The sheet feeding device according to claim 6, wherein the buffer member is rotatably provided, and the buffer member is engaged and retracted by an electromagnetic solenoid. 8. The sheet material feeding device according to claim 6, wherein the buffer member is disposed in the sheet material cassette. 9. The cushioning member is disposed on the sheet material cassette, and an operation cam engageable with the cushioning member is provided at the cassette mounting portion, and the operation cam is moved to the cushioning member during the mounting of the sheet material cassette. 9. The sheet material feeding device according to claim 8, wherein the sheet material feeding device is engaged with the movable base plate, and the buffer member is retracted from the movable base plate when the mounting of the sheet material cassette is completed. 10. A movable base plate for stacking sheet materials, movable plate urging means for urging the movable base plate upward, and urging force of the movable base plate urging means. A sheet material cassette having locking means for locking the movable base plate at a predetermined position when the sheet material cassette is pressed down, a cassette mounting portion to which the sheet material cassette can be mounted, and the cassette mounting A sheet material feeding means for feeding a sheet material loaded on the movable base plate of the mounted sheet material cassette, and a movable member when the sheet material cassette is pushed into the cassette mounting portion. Releasing means for releasing an engagement state between the base plate and the locking means; and a sudden rising operation of the movable base plate when the engagement state between the movable base plate and the locking means is released by the release means. Buffer means for buffering; In the sheet feeding apparatus, the buffer means has a buffer member that engages with the movable base plate to provide resistance when the movable base plate rises, and the movable base plate and the buffer member engage with each other. In this case, a resistance reducing means for reducing the resistance of the movable base plate in the mounting / removing direction of the sheet cassette relative to the resistance of the movable base plate in the rising direction is provided. 11. The apparatus according to claim 11, wherein the resistance reducing means is a roller provided at a portion where the movable base plate and the buffer member engage with each other, and rotating only in a direction in which the sheet material cassette is attached and detached. 11. The sheet feeding device according to 10.