JP3411119B2 - Paper tray - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed tray mounted on an image forming apparatus such as a copying machine, a printer or a facsimile.

[0002]

2. Description of the Related Art In recent years, there has been a demand for space saving of image forming apparatuses such as copying machines, printers and facsimiles.
A so-called front loading type device, in which a paper feed tray that can be pulled out in a direction orthogonal to the paper transport direction is attached to the lower portion of the main body of the device, is the mainstream. Many of the paper feed trays are adapted to accommodate different paper sizes, and in general, a pair of front and rear (front side of the device) that regulates both side positions of the paper in the width direction (direction orthogonal to the transport direction) is used. A side fence (on the rear side) and an end fence that regulates the position of the rear end of the sheet (the rear end in the transport direction) are configured to be movable.

Various paper feed trays having movable side fences and end fences have been proposed. However, in an image forming apparatus that conveys sheets with a central reference, racks are provided on the front side and the rear side of the apparatus. By providing (or mounting) a horizontal extending member having, a rack of both side fences is engaged with a pinion gear, so that a pair of side fences can move while maintaining an equal distance from the center reference. It is widely used because of its good operability. Many of such paper feed trays are provided with a lock means for fixing the side fence so as not to move at a predetermined position.

[0004]

However, when such a sheet feeding tray is used in a front loading type image forming apparatus, the sheet feeding tray is set in the apparatus main body (the sheet feeding tray is set in the apparatus main body). When inserting), the inertial force of the paper is applied to the back side fence. In the conventional paper feed tray, a lock mechanism is provided on the front side fence from the viewpoint of operability, and when the inertial force of the paper at the time of tray setting is applied to the rear side fence, There was a problem that backside fences were displaced or fell due to backlash or bending. When the side fences are displaced or fallen down, the stacked sheets are displaced, causing lateral registration defects and skew of the sheets. Further, in the case of the corner claw type paper feed tray, the paper comes off the corner claws, and a paper feed failure such as a jam or a double feed occurs.

By the way, Japanese Patent Laid-Open No. 62-275932 discloses a paper feed cassette in which a lock mechanism is provided on both side fences. However, in order to change the paper size, the lock mechanism on both sides is disclosed. Both have to be released, and the operability is not good.

Further, when a sheet feeding cassette (tray) having a lock mechanism on both side fences is used in a front loading type image forming apparatus, the lock mechanism provided on the side fences on the back side of the apparatus is used. The tray must be pulled out to a position where it can be operated, the amount of tray pulled out increases, the space for using the apparatus becomes large, and the operability is not good. Further, if the lock is forgotten, a paper feed failure will occur.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems in the conventional paper feed tray and to provide a paper feed tray which does not cause a paper feed defect and has good operability.

[0008]

SUMMARY OF THE INVENTION According to the present invention, the above-mentioned problem is a paper feed tray which is mounted on an image forming apparatus and which can be pulled out and inserted in a direction orthogonal to the paper feed direction, and which are equal to each other based on a paper conveyance standard. In a paper feed tray having a pair of side fences which are provided so as to be movable in a direction orthogonal to the paper feed direction while keeping a distance, and for regulating both sides in the width direction of the stored paper, the movement is performed to each of the pair of side fences. This is solved by providing locking means for locking and one of the locking means is automatically unlocked when the tray is pulled out and locked when the tray is inserted.

Further, in order to solve the above problems, the present invention proposes that the one locking means is a locking means provided on a side fence on the back side of the apparatus.

Further, according to the present invention, in order to solve the above-mentioned problems, the locking means provided on the side fence on the back side of the apparatus is unlocked before the side fence comes out of the main body apparatus when the tray is pulled out. I suggest that.

[0011]

The lock means for locking the movement of the side fence is provided on each of the pair of side fences movably provided on the paper feed tray. Among the locking means provided on each side fence, one locking means is automatically unlocked when the tray is pulled out and automatically locked when the tray is inserted. As a result, one side fence is locked by the locking means when the tray is inserted, so that the side fence is prevented from slipping or falling when the inertial force of the paper is applied. Further, since the side fence is unlocked when the tray is pulled out, it is possible to save the trouble of releasing the locking means when changing the size of the paper and facilitate the operation.

Other functions will be apparent from the description of the embodiments below.

[0013]

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

FIG. 1 is a plan view showing a paper feed tray according to an embodiment of the present invention in a state of being pulled out from an image forming apparatus.
FIG. 2 is a plan view showing the paper feed tray inserted in the image forming apparatus. Further, FIG. 3 is a cross-sectional view showing the front side fence of the paper feed tray. Figure 4
FIG. 6 is a cross-sectional view showing the back side fence when the paper feed tray is inserted into the image forming apparatus. FIG. 5 is a cross-sectional view showing the back side fence in a state where the paper feed tray is pulled out from the image forming apparatus.

In these figures, the paper feed tray 1 is mounted on a front loading type image forming apparatus 100. The image forming apparatus 100 is configured such that the paper conveyance reference is the center reference, and the paper feed tray 1 stacks the transfer paper according to the reference. An end fence 4 for regulating the rear end of the transfer paper is attached on the substrate 8 of the paper feed tray. Further, a pair of front and rear side fences 2 and 3 (on the front side and the back side of the apparatus) for restricting both sides in the width direction of the transfer sheet are slidably arranged in a direction orthogonal to the sheet feeding direction (left and right direction in FIG. 1). It is set up. That is, the side fences 2 and 3 have horizontal portions 2a,
3a, and both end portions 2c, 3c of the horizontal portions 2a, 3a are supported by guide ribs 6, 7 provided on the substrate 8. Further, the horizontal portions 2a and 3a are provided with extending portions 2b and 3b, respectively, and a rack 17 is provided on the opposite surface thereof. Then, both side fences 2, 3 are attached to the pinion gear 9 pivotally mounted on the substrate 8.
Racks 17 are engaged with each other. As a result, the side fences 2 and 3 move from the center of the gear 9 (from the sheet conveyance reference) at equal distances from each other. Further, the guide ribs 6 and 7 have horizontal portions which are vertically bent from the substrate 8 and then bent at right angles. The horizontal portions of the guide ribs 6 and 7 are the end portions 2c and 3 of the side fence.
The vertical movement of the side fences 2 and 3 is restricted by suppressing c from above. In order to avoid complicated drawings,
The extension portions 2b and 3b provided with the pinion gear 9 and the side fence rack 17 are omitted in FIGS.

Also, the horizontal portions 2a, 3 of the side fence
A bottom plate 5 is installed above the a. This bottom plate 5
Is for pushing the transfer paper placed on it to the paper feed position, and the paper feed direction (from left to right in each drawing).
The vicinity of the rear end is pivotally attached to the wall surface of the tray 1 by a shaft 5a (see FIG. 3). Then, the corner claws 14 are attached to the tip ends of the wall surfaces of the side fences 2 and 3 (the right ends in each figure) via mounting members 15. The mounting member 15
Lock levers 10 and 11 are rotatably attached by shafts 19 to the wall surfaces of the side fences 2 and 3 on the side opposite to the side fences. The lock lever 10 of the side fence 2 is
The height is almost the same as that of the fence, and one end of the spring 12 is fixed to the upper end of the fence. Further, the lock lever 11 of the side fence 3 has an upper end protruding higher than the fence, and a leaf spring 13 formed in an inverted U shape is fixed to the upper end portion.

The other end of the spring 12 fixed to the lock lever 10 is fixed to the protrusion 20 of the side fence 2, and the spring 12 exerts a biasing force for rotating the lock lever 10 counterclockwise in FIG. is doing. The lower end portion of the lock lever 10 is pressed against the lock rib 18 provided on the tray substrate 8 by the biasing force of the spring 12 to lock the side fence 2 and restrict the movement thereof. Then, as shown in FIG. 6, when the upper end of the lock lever 10 is manually pushed to contract the spring 12, the lower end of the lock lever 10 is separated from the lock rib 18 and the side fence 2 is unlocked.

By the way, in FIG. 1, the pressure plate 16 fixed to the front and rear frames 104 and 105 of the device 100 has a plate width on the front side of the device narrower than the plate width on the back side, and a taper portion 16a in the middle portion. Are formed. The pressure plate 16 is arranged above the paper feed tray 1 (see FIG.
4), it does not interfere with the tray insertion and withdrawal. In addition, the leaf spring 13 fixed to the lock lever 11 of the side fence 3 is mounted at the mounting position of the pressure plate 1.
It has a height corresponding to 6. Due to the difference in the width of the pressure plate 16, as shown in FIG. 4, when the paper feed tray 1 is inserted into the main body of the apparatus, the plate spring 13 contacts the pressure plate 16 and the lock lever 11 uses the shaft 19 as a fulcrum. It exerts a biasing force to rotate counterclockwise in the figure. This leaf spring 1
The lower end portion of the lock lever 11 is pressed against the lock rib 18 by the urging force of the lock lever 3 to lock the side fence 3 and restrict the movement thereof. On the other hand, when the paper tray 1 is pulled out from the apparatus main body, if the plate spring 13 is pulled out to a position closer to the front side than the tapered portion 16a, as shown in FIG. Are separated by leaf spring 1
The urging force of 3 is reduced, and the side fence 3 is automatically unlocked. Of course, the side fence 3 is automatically locked when the paper feed tray 1 is set in the apparatus main body. Regarding the locked position, the side fence 3 is locked when the tray 1 is inserted to a position where the leaf spring 13 is on the inner side of the tapered portion 16a.

In the paper feed tray 1 of this embodiment, the front and rear side fences 2 and 3 are both provided with a lock mechanism as described above, and the tray 1 is placed on the rear side before being completely inserted into the main body. Since the side fences 3 are locked, when the transfer paper is stored in the tray and set in the main body device, even if the load of the paper is applied to the side fences 3 on the back side, the side fences 3 are not misaligned. Falling can be prevented, and it is possible to prevent the occurrence of lateral registration defects, skews, jams, double feeds, and other paper feed defects. Then, as shown in FIG. 1, if the paper feed tray 1 is pulled out from the image forming apparatus 100, the lock of the side fence 3 on the back side is automatically released. If only the lock is released, both side fences 2 and 3 can be moved, and further, the lock for moving both side fences can be released by the operator (on the front side of the tray). Operability is good.

The unlocking of the side fence 3 on the back side is performed when the tray is pulled out to a position where the leaf spring 13 is on the front side of the taper portion 16a. Therefore, as shown in FIG. The lock has already been released at the time of exiting from the main body device 100. Therefore, when performing paper replacement or the like, it suffices to pull out the tray 1 by the minimum amount required to set the paper, and to pull out until the side fence 3 begins to come out of the main body device. Therefore,
It is possible to reduce the tray withdrawal amount and save the space for operating the apparatus. Comparing this with the conventional example shown in FIG. 8, in the conventional example, the side fence 101 on the back side is
In order to operate the lock mechanism 103 provided further to the inside of the device, it is not enough to expose the side fence 101, and the tray 21 must be pulled out largely until the lock mechanism 103 is exposed and can be operated. . Therefore, this embodiment is advantageous in terms of operating space. Moreover, in the conventional example, in order to adjust the side fence, in addition to the back side, the lock mechanism 103 of the front side fence 102 must be operated (unlocked and locked), which is troublesome and troublesome. is there. But,
In this embodiment, the side fence can be adjusted only by operating the lock mechanism on the front side, which is also advantageous in terms of operability.

In the paper feed tray of the present invention, one of the front and rear side fences equipped with the locking means is automatically unlocked by pulling out the tray (in the embodiment, the back side fence is the back side fence). Since it is only 2), when the transfer paper is set in the tray and the tray is inserted into the main unit, it is possible to automatically lock one side fence (that is, when one side fence is unlocked). The other side fence is locked. Therefore, the movement of the side fence during the setting of the tray is regulated, and the deviation of the stacked sheets is prevented. This is the same when pulling out the tray, and even if one side fence is automatically unlocked, the other side fence is locked, restricting unnecessary movement of the side fence and paper Even if it remains, the gap can be prevented. If both side fences are unlocked when the tray is pulled out, the operability of changing the paper size will be improved, but both side fences will be locked until the side fences are automatically locked when the tray is inserted. The fences are not locked together, and the sheets stacked at this time may be displaced.

[0022]

As described above, according to the image forming apparatus of the present invention, the lock means for locking one of the side fences is automatically unlocked when the tray is pulled out. Only one of the locking means needs to be released, and the operability can be improved by allowing the operation with one hand. Then, since the side fence is automatically locked when the tray is inserted, even if the inertial force of the paper is applied to the side fence, the side fence is prevented from slipping or falling.

According to the second aspect of the present invention, since the side fence on the back side of the apparatus is automatically unlocked when the tray is pulled out, the other locking means for changing the paper size is released on the front side of the apparatus. You just have to unlock the side fence. Therefore, the operation is performed by the operator's hand, and the operability is further improved.

According to the third aspect of the present invention, since the lock means of the side fence on the back side of the device is unlocked before the side fence exits from the main device, when the side fence on the back side comes out of the main device. Has already been unlocked. Therefore, when performing paper replacement or the like, it suffices to pull out the tray by the minimum amount necessary for setting paper, and the operation space can be reduced.

[Brief description of drawings]

FIG. 1 is a plan view showing a paper feed tray according to an embodiment of the present invention in a state of being pulled out from an image forming apparatus.

FIG. 2 is a plan view showing a state in which the paper feed tray is inserted into the image forming apparatus.

FIG. 3 is a sectional view showing a front side fence of the paper feed tray.

FIG. 4 is a cross-sectional view showing the back side fence in a state where the paper feed tray is inserted into the image forming apparatus.

FIG. 5 is a cross-sectional view showing the back side fence in a state where the paper feed tray is pulled out from the image forming apparatus.

FIG. 6 is a cross-sectional view showing a state where the front side fence of the paper feed tray is unlocked.

FIG. 7 is a plan view showing a paper feed tray pulled out by a minimum amount necessary for paper exchange.

FIG. 8 is a plan view showing an example of a conventional paper feed tray.

[Explanation of symbols]

1 Paper tray 2 Front side fence 3 Back side fence 4 end fence 5 bottom plate 6,7 Guide rib 8 tray substrate 9 pinion gear 10, 11 Lock lever 12 springs 13 leaf spring 14 corner nails 16 Pressure plate 16a taper part 17 racks 18 Rock rib 100 image forming apparatus 103 Lock mechanism

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI H04N 1/00 108 H04N 1/00 108C (58) Fields investigated (Int.Cl. ⁷ , DB name) B65H 1/04 320 B65H 1/04 324 B65H 1/26 312 G06G 15/00 514 B41J 13/00 H04N 1/00 108

Claims (3)

(57) [Claims] 1. A paper feed tray which is mounted on an image forming apparatus and which can be pulled out and inserted in a direction orthogonal to a paper feed direction, and which moves in a direction orthogonal to the paper feed direction while keeping an equal distance from a paper conveyance reference. In a paper feed tray having a pair of side fences for restricting both sides in the width direction of the stored sheets, lock means for locking the movement is provided in each of the pair of side fences, and the locking means is provided. A paper feed tray characterized in that one of the locking means is automatically unlocked when the tray is pulled out and is automatically locked when the tray is inserted. 2. The sheet feeding device according to claim 1, wherein the one locking means is a locking means provided on a side fence on the back side of the apparatus. 3. The image according to claim 2, wherein the lock means provided on the side fence on the back side of the device is unlocked before the side fence is pulled out from the main body device when the tray is pulled out. Forming equipment.