JPH03180859A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent an original placing means from being moved even in the case that a copying operation is erroneously started while keeping an ejecting means locked because of a mistake, etc., by an operator by making the locking force of a locking means for locking the ejecting means stronger than the driving force of the original placing means. CONSTITUTION:Projecting parts 19c and 19d are projectingly provided on both side edges of the back board 19b of the ejecting tray 19, and the projecting parts 1c and 1d which are applicable to the projecting parts 19c and 19d are disposed on the side surface of a housing 1a so that both of them can be engaged with each other. Then, the locking force between the projecting part 19c on the driving source side of an original placing board and an original press-contacting board 2b functioning as the original placing means and the projecting part 1c on the housing 1a side is constituted so as to be made stronger than the locking force between the projecting part 19d and the projecting part 1d on the operator side. That means, it is made stronger than the driving force of the original placing means. Thus, the original placing means can be surely prevented from being moved even in the case that the copying operation is erroneously started by the operator in a state that the ejecting tray 19 is folded and locked with the housing 1a.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an image forming apparatus for forming an image on a transfer material, and more specifically, the present invention relates to an image forming apparatus for forming an image on a transfer material, and more specifically, the present invention relates to an image forming apparatus for forming an image on a transfer material. The present invention relates to an image forming apparatus.

<Prior Art> Conventionally, electrophotographic copying machines have been commonly used as image forming apparatuses. Furthermore, in recent years, as image forming apparatuses have become more personalized, small, lightweight, and portable copying machines have come into use.

The copying machine described above uses an exposure lamp to irradiate an original image while scanning an original placed on a platen glass using a drive source, and uses the reflected light to form an image on a pre-charged drum-shaped photoreceptor. An electrostatic latent image is formed, toner is applied to this latent image to form a visible image, and then the toner image is transferred to a transfer material to form an image. Further, the transfer material after the toner image has been transferred is permanently fixed by a fixing device and is discharged onto a discharge tray rotatably attached to the copying machine.

It is inconvenient for the ejection tray to protrude from the side of the copying machine when the copying machine is being carried. For this reason, it is convenient to fold the ejection tray and lock it to the side surface of the copying machine having the ejection port to integrate it. Conventionally, the protrusions provided on both sides of the ejection tray were It was installed by inserting and locking each one between a pair of rollers provided in the.

<Problems to be Solved by the Invention> However, in the above-mentioned conventional technology, if the operator accidentally presses the copy start key with the ejection tray folded and locked on the side of the copying machine main body, In order to cause the platen glass and its cover to move to the ejection tray side by overcoming the locking force of the ejection tray and knocking down the tray, it is necessary to knock over objects placed near the ejection tray side of the copying machine, or to place the platen glass on a wall etc. There was a risk of an unexpected accident such as the cover colliding with the cover and being damaged.

An object of the present invention is to solve the above problems of the prior art and provide an image forming apparatus in which the locking force of the locking means for locking the ejection means to the main body of the apparatus is greater than the driving force of the document placement means. It's about doing.

Means for Solving the Problems> A typical means that solves the problems of the prior art described above and is applied to the embodiments described below is to move a movable original by transmitting a driving force from a driving source. an illumination device for forming an image of reflected light obtained by irradiating the surface of the document on an image carrier for exposure; and a document image formed on the image carrier. It has an image forming means for transferring the image onto a transfer material to form an image, and a discharging means for discharging the transfer material after image transfer, and the discharging means has a locking means for locking on the side surface of the main body of the apparatus. The apparatus is characterized in that it has a locking means, and the locking force of the locking means is larger than the driving force of the original document mounting means.

<Operation> According to the above means, the ejecting means has a locking means for locking to the side surface of the apparatus main body, and the locking force of the locking means is equal to the original i! ! Since the driving force is larger than that of the device stage, even if the image forming operation is started by mistake with the ejecting means locked to the main body of the apparatus due to the operator's carelessness, the document will be removed by the ejecting means. It is possible to prevent the mounting means from moving.

<Embodiment> An embodiment of an image forming apparatus to which the present invention is applied will be described below with reference to the drawings. In this embodiment, a case where the image forming apparatus is applied to an electrophotographic copying machine will be described.

Fig. 1 is a perspective view showing the appearance of the copying machine, Fig. 2 is a partially enlarged explanatory view of the ejection tray, Fig. 3 is an explanatory view showing the locking operation of the ejection tray, and Fig. 4 is an illustration of the feeding roller. FIG. 5 is a perspective view of the conveying device, FIG. 6 is a cross-sectional view showing the general structure of the copying machine, and FIGS. 7(a) and 7(b) are views of the document i.
FIG. 3 is a cross-sectional explanatory diagram showing the drive system of the 3i device stage.

First, the general structure of the copying machine will be explained with reference to FIG.

1 is a main body of a copying machine, and 1a is a casing forming the exterior of the main body 1 of the copying machine.

Place the original on the top of this housing 1a! ! Manuscript for placing! A document placement plate 2a and a document pressure bonding plate 2b having a platen glass, which are lIz means, are provided. The document f2 placement plate 2a and the document pressure bonding plate 2b are driven by a driving force transmitted from a drive source, which will be described later, as indicated by the arrow a in the figure.

It moves back and forth in direction b.

Further, a white reference plate 2C for reflecting light irradiated onto the surface of the document is integrally attached to the back side of the document pressure bonding plate 2b.

i! on the original document placement plate 2a! While the placed original is moving in the direction of arrow a, it is illuminated by an exposure lamp 3, which is an illumination means provided inside the housing 1a, and is illuminated by a light beam provided on the top surface of the housing 1a).
Light is irradiated onto the document surface via the lb. The light reflected from the above document surface is a focusing light transmitter (product name: SELFOC).
, a small-diameter imaging element array such as a bar lens; 4. filter 5
, an image is formed on the circumferential surface of the photosensitive drum 6, which is an image carrier, and exposed.

The photosensitive drum 6 is uniformly charged in advance by a primary charger 7, and an electrostatic latent image is formed by irradiating it with light reflected from the original. This electrostatic latent image is made into a visible image by being coated with toner by a developing device 8.

Reference numeral 9 denotes a guide member capable of supplying a plurality of sheets of transfer material, and the transfer material supplied from the feeding port IO is guided by the inclined surface of the guard member lid and passes through the feeding roller 11a and the separating member 11b. - Next, it is conveyed to the stopped registration roller pair I2, and the skew is corrected. The transfer is synchronized with the leading edge of the electrostatic latent image formed on the photosensitive drum 6 by the registration roller pair 12,
The toner image is transferred to the transfer material by the transfer charger 13 after being transported to the transfer section.

After the toner image is transferred to the transfer material, the toner remaining on the circumferential surface of the photosensitive drum 6 is removed by a cleaning device 14. Further, the transfer material after the image transfer is separated from the photosensitive drum 6 and is conveyed by the feed roller 15 to the conveyance device 16 via the feed guide 15a. This conveying device 16 conveys the transfer material to a fixing device 17, where the transferred image is thermally fixed. Next, the transfer material is transferred to a pair of discharge rollers 18.
, and is discharged onto a discharge tray 19, which is a discharge means rotatably attached to the housing 1a. The fixing device 17 is constructed by pressing a high thermal conductivity film fixing roller 17a passed between rollers onto a fixing roller 17c having a heat source by a pressing member 17b.

The photosensitive drum 6, the charger 7. The developing device 8 and the cleaning device 14 are housed within a cover 20a, and are integrally constructed as a cartridge 20 that can be detachably attached to the copying machine 1 as a whole. This cartridge 20 is held by a guide holding member 21 provided within the housing la.

Further, above the fixing device 17, an exhaust fan 22 is provided for sucking and exhausting warm air inside the casing la.

Next, with reference to FIGS. 7(a) and 7(b), a drive system for the original placing plate 2a and the original pressing plate 2b, which are the original placing means, will be explained.

FIG. 7(a) is a schematic sectional view of the copying machine main body 1 viewed from the drive source side. When the motor 23 is driven, the driving force is transmitted via the gear train 24 to the pinion gear 25 partially exposed on the upper surface of the housing 1a, causing the pinion gear 25 to rotate. This pinion gear 25 is connected to a rack 26 provided on the back side of the document placement plate 2a.
By meshing with the holder, it moves in the directions of arrows a and b in the figure. In addition, the above-mentioned document placement plate 2a and document pressure bonding plate 2
The moving range of b is normally within the length range of the discharge tray 19.

Next, a driving force transmission structure in the gear train 24 will be explained with reference to FIG. 7(b).

In the figure, the rotating shaft 27 has a gear 28 on the drive source side.
Gears 29 are coaxially attached to the load side. A torque limiter 30 is provided between the gear 28 and the gear 29 to transmit or release the driving force from the motor 23.

The general structure of this torque limiter 30 is that a collar 3 is attached to the side of the gear 29 by a stop ring 30a.
A spring 3 interposed in the axial direction between 0b and the boss 30c
0d, the boss 30c is always pressed toward the gear 28 side. Then, by fitting the groove 3(le) having an inclined surface bored on the outer circumferential surface of the end portion of the boss 30c into the groove 30f having an inclined surface provided on the circumferential surface of the gear 28 facing the opposite side, both The driving force is transferred from gear 28 to gear 2 due to the frictional force between
9.

In this torque limiter 30, when a load exceeding a predetermined load torque (for example, l1 kg-cm) is applied, the protrusion 30e slides further into the groove 30 and lifts up, causing the boss 3
0c moves in the direction of arrow C against the elastic force of spring 30d, thereby canceling the transmission of the driving force from gear 28 to gear 29. In detail, gear 2 with a diameter of 2Bam
When a force of 3 kg or more is applied to the platen glass 5 by the platen glass, the torque limiter 30 is activated.

Next, a discharge tray 19 for discharging transfer material used in the copying machine 1 configured as described above will be explained with reference to FIGS. 1 to 3.

As shown in FIG.
A and a document pressure bonding plate 2b are rotatably attached to the side surface of the housing 1a corresponding to the moving direction.

9! 'U [out tray IQ ke prefix 51q3
Qh) - They are connected so as to be movable in this direction and configured to be foldable. Of these, the rear plate 19b is rotatably attached to the side surface of the housing 1a as described above.

Since it is inconvenient to carry the copying machine 1 with the ejection tray 19 open from the side of the housing 1a, the second ejection tray 19 is
As shown in FIG. 2(a) to FIG. 2(C), after folding the front plate 19a onto the rear plate 19b, both of them are rotated to close the transfer material discharge port 18a. It is necessary to lock it integrally with the side surface of 1a.

In this way, the transfer material discharge port 18a can be blocked and dirt can be prevented from entering, and the discharge tray 18a can be prevented from entering.
9 protrudes up to the upper surface of the housing 1a on which the document placement plate 2a and the document pressure bonding plate 2b move, so that it is effective as a stopper in the event of a malfunction. Therefore, as shown in the second (a), there are projections 1 on both side edges of the rear Fi 19b.
9c and 19d are provided in a protruding manner, and protrusions 1c and Id are also provided on the side surface of the housing 1a corresponding thereto, so that the two are respectively locked.

In addition, in the conventional way, the ejection tray was locked with the side of the copying machine by inserting and locking protrusions on both sides of the ejection tray between a pair of rollers on the side of the copying machine, so the ejection tray was the same on both sides. It was locked to the side of the copying machine by the locking force.

In contrast, in this embodiment, the locking force between the protrusion 19c on the drive source side of the document placement plate 2a and the document pressure bonding plate 2b and the protrusion 1c on the housing la side is applied to the locking force between the protrusion 19d and the protrusion d on the operator side.
The locking force is stronger than that of the

That is, as shown in FIGS. 3(a) and 3(b), the protrusion 19c and the locking portion of the protrusion 1c lock the sides perpendicular to the moving direction of the document placement plate 2a and the document pressure bonding Fi 2b. ing. On the other hand, the protrusion 19d and the protrusion d are connected to the document placement plate 2.
The inclined sides are locked to each other with respect to the moving direction of the document pressure bonding plate 2b and the document pressure bonding plate 2b.

This is because the driving force of the original placing plate 2a and the original pressing plate 2b is transmitted more strongly closer to the driving source, so that in the event of a malfunction, a larger load torque is generated on the discharge tray 19 on the driving source side. The protrusion 19c and the protrusion 1c
The locking force is configured to be larger than the maximum load torque (for example, 11 kg·cm) applied to the torque limiter 30.

Therefore, the operator folds the output tray 19 and removes it from the housing 1a.
Even if a copying operation is mistakenly started in a state where the document placement plate tffE2a and the document pressure bonding plate 2b are locked, movement of the document placement plate tffE2a and the document pressure bonding plate 2b can be reliably prevented.

Further, since the locking force between the protrusion 19d on the operator side and the protrusion 1d is weaker than the locking force between the protrusion 19C and the protrusion 1c on the drive source side, the operator releases the locked state of the folded output tray 19. It has the advantage of being easy to use.

Note that the shapes of the protrusions 19c, 19d and the protrusions 1c, 1d are not limited to those of this embodiment, and may be of other shapes.

Further, the means for locking the ejection tray 19 and the copying machine main body l is not limited to the protrusion as shown in the present embodiment, but may also be a locking means using a magnet, for example, by locking the drive source side with three magnets, It is also possible to configure the operation side to be locked with a single magnet.

Next, an outline of the image forming operation of the copying machine I configured as described above will be explained with reference to FIGS. 4 to 6.

First, even if a copying operation is accidentally started with the ejection tray 19 folded up and locked to the side surface of the housing 1a,
As mentioned above, the locking force between the ejection tray 19 and the housing 1a is greater than the driving force of the document placement plate 2a and the document pressure bonding plate 2b. Never move.

Next, after unfolding the folded ejection tray 19 and setting the transfer material in a state where it can be ejected, when the copying operation is started, as shown in FIG.
Between! ! The placed original moves in the directions of arrows a and b in the figure. At this time, the exposure lamp 3 irradiates the document surface with light from inside the housing la through a slit lb provided on the upper surface of the housing la. The reflected light from the document surface is transmitted to the small-diameter imaging element array 4. An image is formed through a filter 5 on the circumferential surface of a photosensitive drum 6 that carries an image. The photosensitive drum 6 is uniformly charged in advance by a primary charger 7, and an electrostatic latent image is formed by irradiating it with light reflected from the original.

This electrostatic latent image is made into a visible image by being coated with toner by a developing device 8.

On the other hand, along the guide member 9 for supplying the transfer material,
The transfer material inserted from the feeding port 10 is transferred to the feeding roller lla.
and the separating member 11b, the sheets are separated one by one, and then the sheets are fed to the stopped pair of registration rollers 12 to correct the skew.

On the paper feed side (right side in the drawing) of the feed roller lla, there is a fourth
As shown in the figure, there is dust on the feed roller lla.

Feed roller cover 1 to prevent dust etc. from adhering
1c is provided in the axial direction along the circumferential surface of the roller. Further, on the paper feeding side of the feeding roller cover 11c, it guides the transferred transfer material, and the rubber feeding roller lla is irradiated with light from the paper feeding port 10, causing the roller surface to deteriorate due to ultraviolet rays. A guard member lid is provided in the axial direction to prevent this.

This guard member lid can prevent outside light from entering through the feed port IO, and can also prevent dust and the like from entering. Further, the guard member lid is a protective cover that prevents the feeding roller 11a from being accidentally contacted and damaged when a finger is placed on the feeding port 10 when the copying machine main body 1 is carried in a horizontal state. It is also used as.

Next, the transfer material is conveyed to the transfer section by the registration roller pair 12 in synchronization with the leading edge of the electrostatic latent image formed on the photosensitive drum 6, and the toner image is transferred to the transfer material by the transfer charger 13. transcribed into.

After the toner image is transferred to the transfer material, the toner remaining on the circumferential surface of the photosensitive drum 6 is removed by a cleaning device 14 in preparation for the next image formation.

Further, the transfer material after the image formation is separated from the photosensitive drum 6 , the rear end is kicked out by a feed roller 15 , and the transfer material is conveyed to a conveyance device 16 . The feed roller 15 has step-like serrations formed on its outer periphery, and kicks out the rear end of the curved transfer material (plain paper) shown by the two-dot chain line in FIG. It is for transporting to the transport device 16 on the side.

As shown in FIG. 5, the conveyance device 16 has a conveyance bell 6c interposed between cylindrical conveyance rollers 16a and 16b, and is rotationally driven by a drive source (not shown). Both sides of the transport roller 1.6a contact the rear end of the transfer material or the sheet surface near the rear end and kick it out onto the transport bell 6C toward the fixing device 17 provided on the downstream side in the transport direction. A flapper 16d, which is a means for kicking out the storage,
16e are each coaxially attached. The flappers 16d and 16e are provided with a plurality of blades on their circumferential surfaces, and these blades contact the rear end of the transfer material and kick out the transfer material downstream. Above flamper 16d
, 16e are set smaller than the width of the postcard-sized transfer material.

The flampers 16d and 16e reliably transport the transfer material (for example, postcards, etc.) shorter than the distance 2 between the transfer charger 13 and the fixing roller 17c, shown by the solid line in FIG. 6, to the fixing device 17 on the downstream side. 16c. Incidentally, the above-mentioned flapper 16d.

The blades provided in 16e are shown in the figure so that the blades are always tilted down from the conveyance path after conveying the transfer material, so that the rear end does not jump up, especially when conveying large-sized transfer materials. The position of the blade is detected by the colander position sensor and the position is corrected.

Further, on both sides of the conveyance roller 16b, there are rubber rollers 16 for reliably conveying large-sized transfer materials, especially in the width direction.
f and 16g are respectively attached coaxially.

Further, on both sides of the feed roller 15 and the conveyance device 16,
Inner conveyance guides 16h, 16i for guiding a transfer material of postcard size L in the width direction, and outer conveyance guides 163, 16k for guiding a transfer material of plain paper size L2 are provided, respectively. These conveyance guides 16h,
The heights of the guide surfaces 16 i , 16 j , and 16 k are bottom-shaped so as to be slightly lower than the outer periphery of the feed roller 15 .

Further, the conveying speed of the conveying device 16 is determined by the conveying speed of the fixing roller 1.
The circumferential speed is set to be slower than the rotational speed of 7c. This can prevent the leading edge of the transfer material onto which the unfixed image has been transferred from hitting the fixing device 17 and disturbing the unfixed image.

The transfer material conveyed to the fixing device I7 by the conveyance device 16 undergoes thermal fixation of the unfixed transferred image, and then is discharged onto the discharge tray 19 from the discharge port 18a via the discharge roller pair 18.

<Effects of the Invention> As described above, in the present invention, the ejection means has a locking means for locking to the side surface of the apparatus main body, and the locking force of the locking means is greater than the drive transmission force of the document placement means. The large configuration prevents the original document placing means from moving even if the image forming operation is started by mistake with the ejecting means locked to the main body of the apparatus due to the operator's carelessness or the like. I can do it.

Further, the locking force of the locking means is the original i! If the drive source side of the ejection means is configured to be larger than the operator side, the operator can easily release the locked state of the ejection means.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the appearance of the copying machine, Fig. 2 is a partially enlarged explanatory view of the ejection tray, Fig. 3 is an explanatory view showing the locking operation of the ejection tray, and Fig. 4 is an illustration of the feeding roller. FIG. 5 is a perspective view of the conveyance device, FIG. 6 is a cross-sectional view showing the general structure of the copying machine, and FIGS. 7(a) and 7(b) show the drive system of the document placement means. It is a cross-sectional explanatory view. 1 is the main body of the copying machine, 1a is the housing, and lb is the slit.

Claims (2)

[Claims] (1) A document placement means for placing a movable document by receiving a driving force from a drive source, and a device for forming an image of reflected light obtained by irradiating light onto the surface of the document on an image carrier. an illumination means for exposing the document image to the image carrier, an image forming means for transferring the original image formed on the image carrier to a transfer material to form an image, and a discharging means for discharging the transfer material after the image transfer. An image characterized in that the ejection means has a locking means for locking to a side surface of the apparatus main body, and the locking force of the locking means is larger than the driving force of the document placement means. Forming device. (2) The locking means has two locations in the width direction of the ejection means,
2. The image forming apparatus according to claim 1, wherein the locking force is greater on the drive source side of the document placement means than on the operator side.