JPH06230666A - Image forming device - Google Patents

Abstract

PURPOSE:To stably carry a developer regardless of the installation direction of a device, in an image forming device having a developing unit developing an electrostatic latent image on a latent image carrier with a powder developer and carrying powder in accordance with the installation direction. CONSTITUTION:In the image forming device forming a latent image on a rotary endless latent image carrier by a latent image forming part. developing the latent image with the powder developer by a developing part 23 and then, transferring the developed image on a sheet by a transfer part, a powder developer carrying mechanism 23-4 carrying the powder developer by a rotary motion, a direction detecting part 5 detecting the installation direction of the device and a control part controlling the rotational direction of the powder developer carrying mechanism 23-4. in accordance with the detecting direction of the direction detecting part 5.

Description

Detailed Description of the Invention

(Table of Contents) Industrial Application Field of the Prior Art (FIG. 10) Problem to be Solved by the Invention Means for Solving the Problem (FIG. 1) Action Example (a) Description of the First Example ( 2 to 7) (b) Description of second embodiment (FIGS. 8 to 9) (c) Description of other embodiments Effect of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a developing device for developing an electrostatic latent image on a latent image bearing member by means of a powder developer and carrying powder according to the installation direction. 2. Description of the Related Art In image forming apparatuses such as copying machines, printers, and facsimile machines, latent image forming apparatuses such as electrophotographic apparatuses are used because of the demand for recording on plain paper.

In such an image forming apparatus, an electrostatic latent image is formed on a photosensitive drum or the like, is developed with a powder developer, is visualized, and the powder developed image is transferred to a sheet. It separates and fixes the powder development image. In order to effectively use the office space in the recent office automation environment, install this image forming device in either the vertical or horizontal direction to reduce the installation area or height of the device according to the needs of the user. It is required to be able to choose to keep the value low.

[0004]

2. Description of the Related Art FIG. 10 is an explanatory diagram of a conventional technique. For example, in an electrophotographic printer, as shown in FIG. 10A, a developing device is used to develop an electrostatic latent image on the photosensitive drum 10 such as an organic photoconductor, a Se photoconductor, or an a-Si photoconductor. 13 are arranged.

The developing device 13 conveys an internal powder developer (eg, one-component magnetic toner, two-component developer) 14 to the developing roller 13-1 by the rotation of the agitator 13-2, and the developing roller 13-1. The powder developer 14 is conveyed to the photosensitive drum 10 by 13-1 to develop the electrostatic latent image on the photosensitive drum 10. The powder developer 14 has fluidity in the direction of gravity, and the powder developer is largely transported by gravity, and the transport direction is limited by the direction of gravity.

For example, as shown in FIG. 10 (A), the powder developer 14 has a fluidity to the bottom of the developing device 13 due to gravity, and in order to convey it to the developing roller 13-1, By rotating the agitator 13-2 in the clockwise direction A,
The powder developer 14 can be conveyed to the developing roller 13-1.

That is, in carrying powder, it is necessary to uniquely determine the carrying direction in consideration of the direction of gravity, and in other carrying directions, it becomes impossible to carry the powder. Further, the conveying direction of the developing roller 13-1 of the developing device 13, the photosensitive drum 1
The conveying direction of the collected developer and the like in the cleaner that cleans 0 was also determined in consideration of the gravity direction.

[0008]

However, the prior art has the following problems. In the conventional image forming apparatus,
The apparatus is only installed horizontally, and as shown in FIG. 10A, it suffices if the powder developer is conveyed in the horizontal installation direction.

However, due to recent diversification of use, FIG.
As shown in FIG. 0 (B), there is a demand to install the device vertically, and when installed vertically, the direction of gravity with respect to the developing device 13 changes, and the flow direction of the powder developer inside changes. 13 has a tendency to flow, and the powder developer 14 cannot be conveyed in the conveying direction A at the time of horizontal installation.
On the contrary, the developer is conveyed in the direction opposite to the developing roller 13-1.

Accordingly, it is an object of the present invention to provide an image forming apparatus capable of stably carrying a developer regardless of the installation direction of the apparatus.

[0011]

FIG. 1 shows the principle of the present invention. According to the first aspect of the present invention, latent images are formed on the rotating endless latent image carrier 20 by the latent image forming sections 21 and 22, the developing section 23 develops with a powder developer, and the transfer section 24 develops the latent image. In the image forming apparatus for transferring the developed image to the sheet, the powder developer transport mechanism 2 for transporting the powder developer by the rotation operation.
3-4 and a direction detection unit 5 for detecting the installation direction of the device
And a control unit 60 for controlling the rotation direction of the powder developer transport mechanism 23-4 according to the detection direction of the direction detection unit 5.

According to a second aspect of the present invention, latent images are formed on the rotating endless latent image bearing member 20 by the latent image forming portions 21 and 22, and the developing portion 23 develops with a powder developer, and the transfer portion. Two
In the image forming apparatus for transferring the developed image to the sheet at 4,
Powder developer transport mechanism 23-4 for transporting the powder developer
And a direction detection unit 5 for detecting the installation direction of the apparatus, and a control unit 60 for selectively operating the powder developer transport mechanism 23-4 according to the detection direction of the direction detection unit 5. Is characterized by.

A third aspect of the present invention is characterized in that, in the first or second aspect, the powder developer transport mechanism 23-4 is provided in the developing section 23.

According to a fourth aspect of the present invention, in the first, second, or third aspect, the powder developer transport mechanism 23-4 is provided in a recovery section for recovering the residual developer on the latent image carrier 20. It is characterized by

A fifth aspect of the present invention is characterized in that, in the first, second, third or fourth aspect, the direction detecting section 5 comprises a pendulum 51 and a detecting means 52 for detecting the pendulum 51. .

[0016]

According to the first aspect of the present invention, since the flow direction of the powder developer changes depending on the gravity direction depending on the installation direction of the apparatus, the direction detection unit 5 for detecting the installation direction of the apparatus is provided, Depending on the installation direction, the controller 60 controls the developer transport mechanism 2
Even if the installation direction of the apparatus is changed and the flow direction of the powder developer is changed, the rotation direction of 3-4 is controlled to change the conveyance direction according to the gravity direction.

According to the second aspect of the present invention, the direction of gravity applied to the powder developer changes according to the installation direction of the apparatus.
A direction detection unit 5 for detecting the installation direction of the apparatus is provided, and the control unit 60 controls the developer transport mechanism 23- depending on the installation direction of the apparatus.
Even if the installation direction of the apparatus is changed and the flow direction of the powder developer is changed by controlling the selective operation of No. 4, the conveyance direction is changed according to the gravity direction.

According to the third aspect of the present invention, the carrying direction of the developer carrying mechanism 23-4 of the developing section 23 is changed according to the installation direction. Even if the flow direction changes, the powder developer can be stably conveyed to develop.

According to the fourth aspect of the present invention, since the carrying direction of the developer carrying mechanism of the collecting section is changed according to the installation direction, the installation direction of the apparatus is changed and the flow direction of the powder developer is changed. Even then, the powder developer can be stably conveyed and collected.

In the fifth aspect of the present invention, the direction detecting section 5 is
Since the pendulum 51 and the detection unit 52 of the pendulum 51 are included, the installation direction of the device can be reliably detected with a simple configuration.

[0021]

【Example】

(A) Description of First Embodiment FIG. 2 is an overall configuration diagram of a first embodiment of the present invention, FIG. 3 is a configuration diagram of essential parts of a first embodiment of the present invention, and FIG. 4 is a first embodiment of the present invention. FIG. 3 is an explanatory diagram of an installation example of the embodiment, showing a cleanerless electrophotographic printer.

In the figure, the same symbols as those shown in FIGS. 1 and 10 are shown, and 20 is a photosensitive drum, and a function-separated type organic photosensitive member is applied on an aluminum drum to a thickness of about 26 μm. And an outer diameter of 24 mm, which is rotated counterclockwise with a peripheral speed of 24 mm / s, 21 is a pre-charger, which is composed of a scorotron that uniformly charges the surface of the photosensitive drum 20, A voltage of -4 to -8 kV is applied to the corona wire 21-1 by the power source Vc, and a varistor R is inserted between the mesh 21-2 attached to the opening of the scorotron and the drum ground. It is controlled to be uniform.

The mesh 21 is used as a power source for generating a voltage corresponding to a predetermined photosensitive member surface potential without using the varistor R.
-2 may be connected. In this embodiment, the photosensitive drum 2
The 0 surface was set to −650V.

Reference numeral 22 denotes an optical unit, which forms an electrostatic latent image by imagewise exposing the uniformly charged photosensitive drum 20, and uses an LED optical system in which an LED array and a selfoc array are combined. And the photosensitive drum 20
By exposing the image according to the image pattern,
An electrostatic latent image of −50 to −100 V is formed.

Reference numeral 23 denotes a developing device, which serves to visualize the electrostatic latent image on the photosensitive drum 20 by attaching charged toner to the electrostatic latent image. The developing device 23 includes a metal sleeve 28-2 and a plurality of magnetic poles provided therein. It has a developing roller 28 composed of a magnet roller 28-1, fixes the magnet roller 28-1 inside the sleeve 28-2, and conveys a magnetic developer described later by rotating the sleeve 28-2.

A power source Vb and a power source Vr are applied to the sleeve 28-2 through a switch SW, and normally, the developing bias voltage Vb is forcibly collected with the residual toner on the photosensitive drum 20 at the time of start-up. Bias voltage Vr is supplied. A developing chamber 23-1 is formed around the developing roller 28, and the developing chamber 23-1 is filled with a two-component developer 40 which is a mixture of a magnetic carrier and a magnetic toner.

Since the developing chamber 23-1 has a constant volume, and the amount of magnetic carrier in the developing chamber 23-1 is constant, magnetic toner is supplied to the developing chamber 23-1 so that the amount of developer in the developing chamber 23-1 is increased. By keeping constant, it is possible to eliminate the need to control the toner density. That is, by filling the developing chamber 23-1 with a carrier amount corresponding to the toner density control point,
The toner density is automatically controlled within a predetermined range.

Further, since the developing chamber 23-1 is always filled with the developer around the developing roller 28, the developer 4 in the developing chamber 23-1 can be formed even if the apparatus described later is a vertical type.
It is possible to prevent the situation where 0 is offset and it becomes impossible to supply a sufficient amount of developer to the developing roller 28. As the developer 40, a magnetite carrier having an average particle size of 70 microns is used as the magnetic carrier, and a magnetic toner manufactured by using a polymerization method having an average particle size of 7 microns is used as the magnetic toner.

Since this polymerized toner has a uniform particle size and a sharp particle size distribution, the toner image on the photosensitive drum 20 and the paper are brought into close contact with each other in the transfer step described later, and the electric field at the transfer portion is uniform. Therefore, the transfer efficiency can be improved as compared with the toner by the conventional pulverization method, and the transfer efficiency, which was 60 to 90% in the pulverized toner, is improved to 90% or more in the polymerized toner. For this toner, the toner concentration is appropriately 5 to 60 wt%, but in this embodiment, it is set to 15 ± 5 wt%.

Reference numeral 23-2 is a doctor blade, and the developer amount supplied to the photosensitive drum 20 by the developing roller 28 is not excessively supplied so as not to be excessively supplied to the electrostatic latent image on the photosensitive drum 20. The adjustment is performed by the gap between the edge of the doctor blade 23-2 and the surface of the developing roller 28, and the normal gap is
It is adjusted to about 0.1 to 1.0 mm.

Reference numeral 23-3 denotes a toner storage unit, which is filled with only magnetic toner and internally provided with an agitator 23-4. By rotating the agitator 23-4, the toner is stored in the developing chamber 23-1. To supply.

The toner supplied into the developing chamber 23-1 is supplied with the developer carrying force of the sleeve 28-2 and the developing roller 28.
Due to the magnetic force and the developer regulating function of the doctor blade 23-2, the toner is agitated in the developing chamber 23-1 and rubs against the carrier to be charged to a predetermined polarity and charge amount. In this embodiment, the charge series of the carrier and the toner is adjusted so as to be negatively charged.

Reference numeral 29 denotes a toner cartridge, which is filled with toner 41, is removably attached to the developing device 23, and is replaced when the toner is empty and supplies the toner 41 to the toner accommodating portion 23-3. .

The angle between the wall surfaces of the toner cartridge 29 and the toner accommodating portion 23-3 is set to about 45 degrees with respect to the gravity direction, and the toner flowing direction is set to 45 degrees. As will be described later in No. 4, even if the apparatus is installed vertically, the toner 41 is smoothly supplied.

Reference numeral 24 denotes a transfer device, which is composed of a corona discharger and electrostatically transfers the toner image on the photosensitive drum 20 onto the paper P. The corona wire has a power supply Vt of +5 to +5.
A voltage of +10 kV is applied to generate an electric charge by corona discharge to charge the back surface of the paper P and transfer the toner image on the photosensitive drum 20 to the paper P. The power supply Vt supplies a constant amount of charge to the paper. It is desirable to supply a constant current power supply that can reduce the decrease in transfer efficiency due to the environment.

Reference numeral 25 denotes a scatter (uniformizing) brush, which is composed of a conductive brush, contacts the photosensitive drum 20, disperses the concentration of the toner remaining on the photosensitive drum 20, and collects it by the developing device 23. Is to facilitate.

A fixing device 27 is for fixing the toner image on the sheet P by heat, and is a halogen lamp 2 which is a heat source.
The heat roller 27-1 and the pressure roller (backup roller) 27-3 each having 7-2 therein are configured to heat the paper P to fix the toner image on the paper P.

Reference numeral 30 is a paper cassette, which accommodates paper and is detachable from the apparatus, 31 is a pick roller, which picks the paper in the paper cassette 30, 32 is a registration roller, and the picked paper Which is abutted against and aligns the leading ends of the sheets and conveys them to the transfer device 24,
33 is a paper discharge roller, which stacks the paper after fixing
The stacker 34 is provided on the upper surface of the apparatus and stacks the discharged sheets.

An installation direction detector 5 is provided in the device for detecting the installation direction of the device, as will be described later with reference to FIG.

The operation of this embodiment will be described. The surface of the photosensitive drum 20 is moved to −6 by the scorotron charger 21.
By uniformly charging to 50 V and then image-exposing with the LED optical system 22, an electrostatic latent image having a background portion of −650 V and a printing portion of −50 to −100 V is formed on the photosensitive drum 20. .

Sleeve 2 of developing roller 28 of developing unit 23
Since the developing bias voltage (-300 V) is applied to the switch 8-2 by the power source Vb by the switch SW, this electrostatic latent image is superposed negatively by the developing device 23 by stirring with the carrier. It is developed with toner to form a toner image.

On the other hand, the paper is picked from the paper cassette 30 by the pick roller 31, the leading ends are aligned by the registration roller 32, and the paper is conveyed toward the transfer device 24. And
The toner image is transferred onto the paper P by an electrostatic force by the transfer device 24.
The toner image on the sheet P is fixed on the sheet P by the fixing device 27, passes through the U-shaped conveyance path, and is ejected to the stacker 34 by the sheet ejection roller 33.

The toner remaining on the photosensitive drum 20 after the transfer passes through the scorotron charger 21 and the LED optical system 22, reaches the developing device 23, and is collected and collected by the developing roller 28 at the same time as the next developing process. The toner is reused in the developing device 23.

In such a cleanerless process,
No mechanism for discarding toner is required, device can be downsized, space for storing waste toner is not required, toner that does not contribute to printing is eliminated, and it is economical. Therefore, in order to protect the environment, in order to remove the toner on the photosensitive drum 20 with the cleaner, the photosensitive drum 10 is scraped with the cleaner, but since the cleaner is not used, the life of the photosensitive drum 20 is extended. There is.

In this recording process, the untransferred toner on the photoconductor 20 is dispersed by the scatter (uniformizing) brush 25, and then the corona charger 21 with the toner attached on the photoconductor drum 20. , The LED optical system 12 exposes the image, and the developing device 13 collects the transfer residual toner and develops the toner at the same time.

In the toner dispersion by the uniformizing brush 25, the toner concentrated in a part is dispersed to reduce the toner amount per unit area, and the developing device 2
3 for easy recovery, and further, ion shower in the corona charger 21 and filter in the image exposure process.
It has the effect of suppressing the effect.

The point of this recording process is to collect the toner on the photosensitive drum 20 at the same time as the developing step, and the explanation will be made assuming that the photoreceptor 20 is negatively charged and the toner is also negatively charged.

The surface potential of the photoconductor 20 is set to -500 to -1000 V by the charger 21, and the potential of the exposed portion where the potential is lowered by the image exposure is lowered to 0 to -several tens of V and the electrostatic latent potential is reduced. When an image is formed and developed, a developing bias voltage (for example, -300
V) is applied to the developing roller of the developing device 23.

In the developing step, the negative charging toner attached to the developing roller is attached to the electrostatic latent image on the photoconductor 20 by the electric field formed by the developing bias and the latent image potential, and the toner is attached to the toner. Forming an image.

In the cleaner-less process, at the same time as this developing process, the transfer residual toner dispersed on the photosensitive drum 20 in the homogenizing process is caused by the electric field formed by the surface potential and the developing bias, so that the photoconductor 20 is exposed. It is collected from above by a developing roller.

This device can be made extremely small because it does not have a cleaner. As shown in FIG. 2, the length of the device is 305 mm without the paper cassette 30, and the paper cassette 30 is Even when set, the height is 445 mm and the height is 100 mm, and it is easy to install on a desk as a printer for personal use.

In addition to the horizontal installation in which the paper cassette 30 of FIG. 2 is horizontal to the installation surface, as shown in FIG. 4, the upper surface of FIG. 2 is provided on the installation surface and the paper cassette 30 is perpendicular to the installation surface. It is possible to form an image in a vertical installation, which reduces the installation area.

Further, even when the cleanerless process is performed, the pre-charger 21 and the transfer device 24 are constituted by the non-contact type discharger, so that the toner on the photosensitive drum 20 does not adhere to these units and is stable. Uniform charging and transfer can be performed.

FIG. 5 is an explanatory view of the installation direction detecting mechanism of the first embodiment of the present invention, FIG. 6 is a block diagram of the first embodiment of the present invention, and FIG. 7 is an explanatory view of the first embodiment of the present invention. is there. In FIG. 5, the device direction detection mechanism 5 includes a pendulum 50 that rotates around a rotation shaft 51, and a photocoupler 52 that is fixed to the device and that has an optical path blocked by the pendulum 50 and that detects the pendulum 50. There is.

In this embodiment, as shown in FIG. 5A, when the device is installed in one direction (for example, the lateral direction), the pendulum 50 follows the direction of gravity and the photocoupler 52.
Since it is blocked, the output of the photocoupler 52 can detect that the device is installed in one direction.

As shown in FIG. 5B, when the device is installed in another direction (for example, the vertical direction), the pendulum 5
Since 0 follows the direction of gravity and does not block the photocoupler 52, the output of the photocoupler 52 can detect that the device is installed in another direction.

In the block diagram of FIG. 6, reference numeral 60 is a control unit, which is composed of a microprocessor (MPU) and controls the operation of the entire apparatus. Reference numeral 61 is a motor, which is driven by the control of the control unit 60. The rotational direction drive of the agitator 23-4 and the like of the developing device 23 is the installation direction detector 5 described above, the detection output of which is read by the controller 60.

The operation will be described with reference to FIG.
As shown in FIG. 7A, when the apparatus is installed horizontally, the developing device 23 is located on the right side of the photosensitive drum 20, and as shown in FIG.
Since the angle of the wall surface 3-3 is about 45 degrees with respect to the gravity direction, the toner 41 is smoothly supplied to the agitator 23-4.

At this time, the installation direction detector 5 is shown in FIG.
As shown in, the photo sensor 52 is in the gravity direction of the pendulum 50, and the photo sensor 52 is blocked by the pendulum 50, so the output of the photo sensor 52 becomes a high level,
The control unit 60 recognizes the horizontal installation.

In this horizontal installation, as shown in FIG. 7A, due to gravity, the toner 41 is transferred to the toner storage portion 23.
-3, since it has fluidity in the bottom direction, the agitator 23-4 needs to scrape up the toner on the bottom side of the toner storage portion 23-3 and supply it to the developing chamber 23-1. Therefore, when the controller 60 recognizes that the agitator 23-4 is installed horizontally, the controller 61 drives the motor 61 so as to rotate the agitator 23-4 in the counterclockwise direction, and the agitator 23-4 causes the toner on the bottom of the toner container 23-3 to move. 41 is scraped up and supplied to the developing chamber 23-1.

On the other hand, as shown in FIGS. 4 and 7 (B), when the apparatus is installed vertically, the developing device 23 is set to the photosensitive drum 20.
However, the angle between the toner cartridge 29 and the wall surface of the toner accommodating portion 23-3 is about 4 degrees with respect to the gravity direction.
Since it is set at 5 degrees, even if installed vertically, the angle between the toner cartridge 29 and the wall surface of the toner accommodating portion 23-3 is approximately 45 degrees with respect to the gravity direction, and the toner is smoothly supplied to the agitator 23-4. it can.

The angle between the wall surface of the toner cartridge 29 and the wall surface of the toner accommodating portion 23-3 is about 45 ° ± 5 ° with respect to the direction of gravity so that a good result can be obtained.

At this time, the installation direction detector 5 is shown in FIG.
As shown in, the photo sensor 52 is not in the gravity direction of the pendulum 50, and the photo sensor 52 is not blocked by the pendulum 50. Therefore, the output of the photo sensor 52 becomes low level, and the control unit 60 recognizes that it is installed vertically. To do. In this vertical installation, as shown in FIG. 7B, due to gravity, the toner 41 has fluidity toward the developing chamber in the toner storage portion 23-3, so that the agitator 23-4 stores the toner. It is necessary to convey the toner on the developing chamber side of the section 23-3 and supply it to the developing chamber 23-1.

Therefore, when the control section 60 recognizes that the agitator 23-4 is installed vertically, it drives the motor 61 so as to rotate the agitator 23-4 clockwise, and the agitator 23-4 causes the toner storage section 23-3 to develop. The toner 41 on the chamber side is supplied to the developing chamber 23-1.

Further, when installed vertically, the developer may drop from the developing device 23, but since the magnetic two-component developer is used as the developer, the developer is attracted to the developing roller 28 by a magnetic force. Therefore, even if the developer is installed vertically, the developer hardly drops. In particular, when the magnetic carrier and the magnetic toner are used, both the carrier and the toner are held by the magnet roller 28-1 of the developing roller 28, so that the developer can be prevented from further dropping, and even if the developer is installed vertically, Therefore, stable development becomes possible.

In this way, when the apparatus can be operated by changing the installation direction of the apparatus, the installation direction of the apparatus is detected, the conveying direction of the developer is changed, and the developer is moved in the gravity direction. It is possible to stably convey the developer according to the property.

Since the installation direction detector 5 is composed of a pendulum and a pendulum detector, the installation direction can be reliably detected with a simple structure.

(B) Description of the Second Embodiment FIG. 8 is a block diagram of the second embodiment of the present invention, and FIG. 9 is an explanatory view of the second embodiment of the present invention. 8 through FIG.
The same parts as those indicated by are indicated by the same symbols, and around the photosensitive drum 20 rotating clockwise, the corona charger 21, the LED optical system 22, the developing device 23a, the transfer device 24, and the cleaner 15 are provided. , The static elimination lamp 16 is arranged, the paper in the paper cassette 30 is picked up by the pick roller 31, conveyed to the transfer device 24, the toner image on the photosensitive drum 20 is transferred, fixed by the fixing device 27, and discharged. The rollers 33 eject the sheets to the stacker 34.

The developing device 23a includes a toner storage chamber 23-
3 and a developing chamber 23-1, and an agitator 23-4 that conveys the toner 42 is provided in the toner storage chamber 23-3.
A developing roller (magnetic roller) 28 is provided in the developing chamber 23-1.

The toner 42 is preferably a one-component magnetic toner or a two-component developer from the viewpoint of preventing the developer from falling off during vertical installation. This device is also provided with the installation direction detector 5 as in the first embodiment.

When the apparatus shown in FIG. 8 is installed horizontally, the toner 42 in the developing unit 23a has a fluidity to the bottom of the developing unit 23a due to gravity, and therefore, the horizontal installation detection output of the installation direction detector 5 causes the toner 42 to flow. The control unit 60 drives the motor 61 so as to rotate the agitator 23-4 clockwise. As a result, the toner 42 on the bottom of the developing device 23a is scraped up by the agitator 23-4 and conveyed to the developing chamber 23-1.

On the other hand, when the apparatus of FIG. 9 is installed vertically,
In the developing device 23a, the toner 42 has fluidity toward the side surface side of the toner storage chamber 23-3 according to the gravity, and therefore the control unit 60 causes the agitator 23-4 to operate by the vertical installation detection output of the installation direction detector 5. The motor 61 is driven so as to rotate counterclockwise. As a result, the toner 42 on the side surface of the developing device 23a is conveyed to the developing chamber 23-1 by the agitator 23-4.

Also in this embodiment, since the magnetic developer is used as the developer, the developer is held on the developing roller 28 by the magnetic force. Therefore, even if the developer is installed vertically, the developer hardly drops. Does not happen.

In particular, when a developing method is used in which both the toner and the carrier are consumed by using the magnetic carrier and the magnetic toner having almost the same size as the magnetic toner, both the carrier and the toner are in the developing roller 28. Magnet roller 28-
Since it is held at 1, the developer can be prevented from falling further, and stable development can be performed even with such vertical installation.

Also in this embodiment, the toner storage chamber 23-
3 and the developing chamber 23-1, the angle relationship is 4 with respect to the gravity direction.
5 ° ± 5 °, that is, the flow direction of the developer is 45 °
By setting the angle ± 5 degrees, the transportability of the toner 42 to the developing roller 28 can be maintained regardless of whether the toner 42 is installed horizontally or vertically. In the case of the vertical installation, as shown in FIG. 9, by providing the stacker plate 35 at the rear stage of the paper discharge roller 33, the stacker can hold the printing paper even when installed vertically.

(C) Description of Other Embodiments In addition to the above embodiments, the present invention can be modified as follows.

A combination of a pendulum and a photocoupler is used as the installation direction detector 5, but it detects a mercury relay that opens and closes due to an inclination, and a change in capacitance due to a change in the presence or absence of fluid between the electrode plates. Other types of tilt sensors, such as those that do

Although the rotating direction of the agitator that conveys the developer is changed, depending on the installation direction, the developing roller,
The rotation direction of the developer transport screw or the transport mechanism for transporting the waste toner in the cleaner to the developing device and collecting the waste toner may be switched.

The developer transport mechanism may be controlled to operate or not operate depending on whether the developer transport mechanism is vertically or horizontally installed. Further, a plurality of transport mechanisms for transporting the developer transport mechanism in the opposite direction. For example, two agitators 23-4 that rotate in mutually opposite directions may be provided in the toner storage portion 23-3 of FIG. 3, and these agitators 23-4 may be selectively operated.

Although the LED optical system is used as the image exposure section, a laser-optical system, a liquid crystal shutter optical system, an EL (electroluminescence) optical system or the like may be used.

In the above-mentioned embodiments, the latent image forming mechanism has been described as an electrophotographic mechanism, but it can also be used in a latent image forming mechanism for transferring a toner image (for example, an electrostatic recording mechanism), and the sheet P is used.
Is not limited to paper, and other media can be used.

Although the image forming apparatus has been described as a printer,
It may be another image forming apparatus such as a copying machine or a facsimile.

The present invention has been described above with reference to the embodiments.
Various modifications are possible within the scope of the invention, and these modifications are not excluded from the scope of the invention.

[0084]

As described above, according to the present invention,
It has the following effects.

Since the installation direction detector is provided and the developer transfer mechanism is controlled in accordance with the installation direction, the developer can be stably transferred depending on the flow direction of the developer regardless of the vertical or horizontal orientation. It will be possible.

Therefore, regardless of the installation direction of the device,
Stable image formation becomes possible, and the installation direction of the device can be provided with flexibility according to the needs of the user.

[Brief description of drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is an overall configuration diagram of a first embodiment of the present invention.

FIG. 3 is a configuration diagram of a main part of a first embodiment of the present invention.

FIG. 4 is an explanatory diagram of an installation example of the first embodiment of the present invention.

FIG. 5 is an explanatory diagram of a device direction detection mechanism according to the first embodiment of this invention.

FIG. 6 is a block diagram of a first embodiment of the present invention.

FIG. 7 is an explanatory diagram of the first embodiment of the present invention.

FIG. 8 is a configuration diagram of a second embodiment of the present invention.

FIG. 9 is an explanatory diagram of the second embodiment of the present invention.

FIG. 10 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 10, 20 Photosensitive drum (latent image carrier) 11, 21 Pre-charger 12, 22 LED optical system (latent image forming part) 13, 23 Developing device 14, 24 Transfer device 23-4 Agitator 28 Developing roller 30 Paper cassette 34 Stacker 5 Installation direction detector 60 Control unit

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tomohisa Mikami 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Within Fujitsu Limited

Claims (5)

[Claims] 1. A rotating endless latent image carrier (2)
0) a latent image is formed in the latent image forming section (21, 22), and is developed with a powder developer in the developing section (23) to form a transfer section (24).
An image forming apparatus for transferring a developed image to a sheet by means of a powder developer transport mechanism (23-4) for transporting the powder developer by a rotating operation, and a direction detector for detecting the installation direction of the apparatus. (5) and a control unit (6) for controlling the rotation direction of the powder developer transport mechanism (23-4) according to the detection direction of the direction detection unit (5).
0) and 0) are provided. 2. A rotating endless latent image carrier (2)
0) a latent image is formed in the latent image forming section (21, 22), and is developed with a powder developer in the developing section (23) to form a transfer section (24).
In an image forming apparatus for transferring a developed image to a sheet with a sheet, a powder developer transport mechanism (23-
4), a direction detection unit (5) for detecting the installation direction of the apparatus, and the powder developer transport mechanism (23-4) is selectively operated according to the detection direction of the direction detection unit (5). Control unit (60)
An image forming apparatus comprising: 3. The powder developer transport mechanism (23-4)
The image forming apparatus according to claim 1 or 2, wherein the image forming apparatus is provided in the developing section (23). 4. The powder developer transport mechanism (23-4)
4. The image forming apparatus according to claim 1, wherein the latent image carrier (20) is provided in a collecting section for collecting the residual developer. 5. The pendulum (5)
The image forming apparatus according to claim 1, 2 or 3 or 4, comprising 1) and a detection means (52) for detecting a pendulum (51).