JPH0890828A - Image forming device - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide an image forming apparatus in which a control element of a control electrode can be exchanged integrally with a toner cartridge. [Structure] An aperture 6 for passing a toner 16 is formed on an insulating sheet 2 of an aperture electrode body 1, a control electrode 4 is provided around the aperture 6, and from the control electrode 4 to an edge portion 2a of the insulating sheet 2, The conducting wire 5 is formed. The control element 7 for applying the control voltage to the control electrode 4 is provided on the toner case 11 of the detachable toner cartridge 10, and the control element 7 and the conducting wire 5 are detachably connected by the connector 9 and the connection cable 9a. ing. Control element 7
Are replaced integrally with the toner cartridge 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus which can be used in copying machines, printers, plotters, facsimiles and the like.

[0002]

2. Description of the Related Art Conventionally, as one of image forming apparatuses, a plurality of small holes (hereinafter referred to as apertures) are provided in a row on an insulator, and control electrodes are arranged around each aperture. An image forming apparatus that controls the passage of an aperture of toner particles by applying a control voltage according to an image signal to a control electrode to obtain an image on an image recording medium such as a printing paper is disclosed in Japanese Patent Laid-Open No. 6-155798. It is disclosed.

In such an image forming apparatus, as shown in FIG. 5, a toner cartridge 110 and an image recording medium 120 are opposed to each other with an aperture electrode body 101 having a large number of apertures 106 and control electrodes 104 formed therebetween. further,
The back electrode 122 is provided on the back surface of the image recording medium 120.

Further, as shown in FIG. 6, the aperture electrode body 101 of the image forming apparatus 100 includes a plurality of apertures 106 having a diameter of 100 μm on an insulating sheet 102 made of polyimide having a thickness of 25 μ, and a longitudinal direction of the aperture electrode body 101. Are formed in a row in a row and have a thickness of 1 μm around the aperture 106.
Control electrodes 104 made of copper foil each having a width of m and a width of 20 μm are formed. The control electrode 104 is connected to a control element 107 for turning on / off a control voltage to the control electrode by a conductive wire 105, and the control element 107 is connected to the wiring 1
09 is connected to the control voltage application circuit 108 shown in FIG.

Further, as shown in FIG. 5, the aperture electrode body 101 is mounted on a body frame (not shown) of the image forming apparatus 100 so that the surface on which the control electrode 104 is provided faces the image recording medium 120. It is fixed.

Further, in the toner cartridge 110, the toner 11 is attached to the aperture 106 of the aperture electrode body 101.
A toner carrying roller 114 for supplying 6 is provided, and a toner supply roller 112 for charging and carrying the toner 16 on the toner carrying roller 114 is arranged on the right side of the toner carrying roller 114. Further, on the right side of the toner supply roller 112, the toner 16 stored in the toner case 111 is agitated, and the toner supply roller 11 is stirred.
2 is provided with an agitator 117.

In this image forming apparatus 100, the control voltage applying circuit 10 is applied to the control electrode 104 on the aperture electrode body 101.
By applying a control voltage corresponding to the image signal from No. 8 via the control element 107 and applying a voltage of +1 kV from the DC power supply 124 to the back electrode 122, the toner 116 carried by the toner carrying roller 114 is prevented from flying. Control and
An image is formed on the image recording medium 120.

[0008]

However, in the conventional image forming apparatus 100 as described above, the control electrode 10 is used.
4 and the conductive wires 105 are densely arranged with a slight gap, so that if a conductive foreign substance adheres between the control electrodes 104 or between the conductive wires 105, a short circuit may occur between the control electrodes 104 or between the conductive wires 105. In this case, the current flowing through the control element 107 exceeds the rated current of the control element 107, the control element 107 may be damaged if the time is long, and the control element 107 may be deteriorated even if the time is short.

When a conductive foreign substance enters between the control electrode 104 and the back electrode 122, a short circuit may occur between the control electrode 104 and the back electrode 122. In this case, the voltage of +1 kV applied to the back electrode 122 is also applied to the control electrode 104, and the voltage of +1 kV is also applied to the control element 107 connected to the control electrode 104. Exceeding the rated voltage of the control element 107,
The control element 107 was sometimes damaged.

Further, if conductive foreign matter is mixed in the toner 116, discharge may occur between the toner carrying roller 114 and the control electrode 104, and the control element 107 connected to the control electrode 104 is fed with a rated current. In some cases, a current of more than 10 could flow and destroy the control element 107.

Therefore, the control element 107 provided on the aperture electrode body 101 may be defective or deteriorated when the image forming apparatus is used for a certain period of time, so that the control element 107 needs to be replaced.

For this replacement, it is necessary to remove the aperture electrode body 101 from the body frame, but the aperture electrode body 10
No. 1 is pulled by a spring (not shown) and fixed to the main body frame, which requires time and effort for removal, and also requires alignment for attachment, which is complicated. Further, the defective control element 107 on the aperture electrode body 101
Since it is difficult to replace only the aperture electrode body, the entire aperture electrode body 101 was eventually replaced.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an image forming apparatus in which the control element can be replaced together when the toner cartridge is replaced.

[0014]

In order to achieve this object, an image forming apparatus according to the invention described in claim 1 is provided with a plurality of holes through which charged toner passes, and the holes are provided for each of the holes. An electrode array having a control electrode for controlling the passage of the supplied toner, a removable toner cartridge for storing toner supplied to a hole provided in the electrode array, and the toner cartridge provided in the toner cartridge. And a control element that controls the application of voltage to the control electrode when the device is mounted.

Further, in the image forming apparatus of the invention described in claim 2, in addition to having the configuration of the image forming apparatus of the invention described in claim 1, a connector for connecting the control electrode and the control element is provided. I have it.

Further, in the image forming apparatus of the invention described in claim 3, a plurality of holes for passing charged toner are formed, and a control electrode provided for each hole to control passage of the toner. An electrode array having, a control element provided on the electrode array, for controlling application of a voltage to the control electrode, and mounting the electrode array, and
And a detachable toner cartridge for storing the toner supplied to the holes provided in the electrode array.

[0017]

According to the image forming apparatus of the present invention having the above structure, a voltage is applied to each control electrode provided in the electrode array by the control element provided in the toner cartridge. Then, by applying a voltage to each control electrode, the passage of the charged toner is controlled for each hole of the electrode array. In this image forming apparatus, since the removable toner cartridge is provided with the control element,
Every time the toner cartridge is replaced, the control element is replaced.

In the image forming apparatus according to the second aspect of the invention, the control element and the control electrode provided on the detachable toner cartridge are connected by the connector.

Further, in the image forming apparatus according to the third aspect of the invention, the control element is provided on the electrode array, and the electrode array is mounted on the removable toner cartridge, so that the toner cartridge is replaced. Every time, not only the control element but also the entire electrode array is replaced.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus 50 which is an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a view showing the arrangement of an image forming apparatus 50 of the present invention. The central portion of the image forming apparatus 50 is
In order to control passage of the toner 16, an aperture electrode body 1 having a plurality of apertures 6 which are holes is provided, and on the left side of the aperture electrode body 1, a gap of 1 mm from the aperture electrode body 1 is held, The electrode plate 22 is arranged on a chassis (not shown). On the right side of the aperture electrode body 1, the toner cartridge 10 is arranged so as to face the back electrode 22 with the aperture electrode body 1 interposed therebetween. Further, the image recording medium 20 on which the image is recorded and which is conveyed in the direction of arrow A is inserted and conveyed into the gap between the aperture electrode body 1 and the back electrode plate 22.

Conveying rollers 19a and 19b are axially supported by a chassis (not shown) on the upstream side of the image recording medium 20 in the conveying direction. A fixing device 26 that fixes a toner image on the image recording medium 20 is provided on a chassis (not shown) on the downstream side of the image recording medium 20 in the transport direction. The fixing device 26 includes a heat roller 26b and a driven roller 2
Although the heat roller 26b is not necessarily used, the pressure roller may be used instead of the heat roller 26b to fix the toner image by pressure.

Next, referring to FIG. 2, the image forming apparatus 50.
The aperture electrode body 1 used for the above will be described.

The aperture electrode body 1 has a plurality of apertures 6 having a diameter of 100 μm formed in a row on an insulating sheet 2 made of polyimide having a thickness of 25 μm, and a copper foil having a thickness of 1 μm on the upper surface of the insulating sheet 2. A control electrode 4 is formed for each aperture 6. A plurality of conducting wires 5 are provided in parallel from each control electrode 4 toward the edge portion 2a of the insulating sheet 2. The conductor 5 is made of the same copper foil as the control electrode 4, and is formed up to the edge portion 2 a of the insulating sheet 2. Here, the connector 9 shown in FIG. 1 is detachably fitted to the edge portion 2a of the insulating sheet 2, and the control voltage is applied to the control electrode 4 via the connector 9 and the connection cable 9a connected to the connector 9. Is connected to the control element 7 for applying.

Here, the method of forming the control electrode 4 and the conductive wire 5 will be described. A copper foil is provided on the entire one surface of the insulating sheet 2 by adhesion or vapor deposition, and the control electrode 4 and the conductive wire 5 are provided on the copper foil surface. Is formed by etching.

Although not shown in FIG. 2, the aperture electrode body 1 is provided with a fixing member for fixing it to a main body frame (not shown) of the image forming apparatus 50. This fixing member is provided by a plurality of springs (not shown). It is pulled and fixed to a frame (not shown) of the image forming apparatus 50. Therefore, tension is constantly applied to the aperture electrode body 1.

Next, the structure of the toner cartridge 10 of the image forming apparatus 50 will be described with reference to FIG.

The toner cartridge 10 is provided with a toner case 11 which also serves as a housing for the entire toner cartridge 10, and a toner reservoir 21 in which toner 16 is stored is provided on the right side of the toner case 11. There is. In addition, unused toner 1 is stored in the toner reservoir 21.
6 and the collected toner 16 are mixed and stirred,
The agitator 17 having two blades is used in the toner case 1.
1 is pivotally supported.

A toner supply roller 12 that conveys the toner 16 agitated by the agitator 17 to a toner carrying roller 14, which will be described later, is axially supported by the toner case 11 diagonally below the agitator 17.

On the left side of the toner case 11, the toner 1
A cylindrical toner carrying roller 14 carrying 6 and carrying it to the aperture electrode body 1 is axially supported in the toner case 11. Further, the toner carrying roller 14 and the toner supply roller 12 are arranged in parallel with each other and are in contact with each other via the toner layer carried on the toner carrying roller 14.
Further, the toner carrying roller 14, the agitator 17, and the supply roller 12 are axially supported by the toner case 11 with their rotation axes parallel to each other, and are driven by a drive motor (not shown).

Further, as shown in FIG. 1, the toner case 1
In FIG. 1, above the toner carrying roller 14, the amount of the toner 16 carried by the toner carrying roller 14 is adjusted to be uniform on the roller surface of the toner carrying roller 14, and the toner 16 is made uniform. A toner layer regulating blade 18 for charging is provided, and the toner layer regulating blade 18 is fixed to the toner case 11 by pressing one end of the toner layer regulating blade 18 against the toner carrying roller 14.

Further, the toner cartridge 10 is detachably fixed to the body frame (not shown) of the image forming apparatus 50 by a detaching mechanism (not shown) so that the toner carrying roller 14 is brought into contact with the aperture 6 of the aperture electrode body 1. As shown in FIG. 3, each aperture 6 has its center line 30 passing on a straight line connecting the leftmost end of the peripheral surface of the toner carrying roller 14 and the central axis 32 of the toner carrying roller 14. It is located in. This allows
The aperture 6 makes uniform contact with the toner carrying roller 14 at the leftmost end of the toner carrying roller 14, and the distribution of the toner 16 carried by the toner carrying roller 14 passing between each aperture 6 and the toner carrying roller 14 is shown in the aperture 6. It can be made uniform in the entire area. Further, since the wall surface of the aperture 6 and the flying direction of the toner 16 are parallel to each other, the toner can be stably jetted.

As shown in FIG. 3, the aperture electrode body 1 itself has an aperture 6 with respect to the toner carrying roller 14.
Is pressed so that it bends slightly at the same angle. As a result, the contact area between the aperture electrode body 1 and the toner carrying roller 14 can be increased, and the aperture 6 can be pressed uniformly, so that the toner 16 supplied to the aperture 6 by the toner carrying roller 14 can be prevented. It is possible to suppress the occurrence of uneven density as much as possible.

Further, as shown in FIG. 1, the toner case 1
A control element 7 for controlling application of a control voltage to the control electrode 4 is provided on the substrate 7 a on the lower surface of the substrate 1. The substrate 7 a is bonded to the toner case 11. here,
As the control element 7, an IC for switching is generally used, but the control element 7 is not limited to the IC and may be a transistor or the like.

On the board 7a on which the control element 7 is provided, a connection cable 9a connected to each terminal of the control element 7 is provided.
Is provided, and a connector 9 that is detachably fitted to the edge portion 2a of the insulating sheet 2 is provided at the tip of the connection cable 9a.
Thus, the conductive wire 5 provided on the insulating sheet 2 and each terminal of the control element 7 are connected.

The control element 7 is also connected to the control voltage application circuit 8 by a detachable connector (not shown). The control voltage applying circuit 8 is configured to apply a voltage of +50 V to the control electrode 4 based on an image signal sent from an image signal receiving device (not shown). The image signal receiving device is connected to an external device such as a computer, an image reading device, or an image communication device.

A DC power source 24 is provided between the back electrode plate 22 and the toner carrying roller 14 as shown in FIG.
The DC power supply 24 is adapted to apply a voltage of +1 kV to the back electrode plate 22.

Next, the image forming operation of the image forming apparatus 50 configured as described above and the operation of replacing the control element 7 by replacing the toner cartridge 10 will be described with reference to FIG.

First, when an image signal is transmitted from an external device to an image signal receiving device (not shown), the image signal is temporarily stored in the image signal receiving device, and thereafter, a central control (not shown) is performed from the image signal receiving device. Image signal to the device,
It is transmitted sequentially. The central controller rotates a drive motor (not shown) to rotate the agitator 17 in the direction of arrow B. Then, the toner 16 in the toner reservoir 21 is agitated by the two blades of the agitator 17, conveyed to the toner supply roller 12, and adheres to the surface of the toner supply roller 12.

Next, the toner supply roller 12 is rotated in the direction of arrow C by the rotation of a drive motor (not shown), and the toner 16 adhering to the toner supply roller 12 is rubbed against the toner carrying roller 14 and is negatively charged. Then, the toner is carried on the toner carrying roller 14. The toner 16 carried on the toner carrying roller 14 is conveyed to the toner layer regulating blade 18 by the rotation of the toner carrying roller 14 in the direction of the arrow D by a drive motor (not shown), and is thinned by the toner layer regulating blade 18. In addition, the charging is made uniform. After that, the toner carrying roller 14 is rotated in the direction of the arrow D to be conveyed toward the aperture electrode body 1. Then, the toner 16 on the toner carrying roller 14 is supplied below the aperture 6 while being rubbed by the insulating sheet 2 of the aperture electrode body 1.

Next, the central control unit (not shown) sends the image signal received from the image signal receiving unit to the control voltage applying circuit 8. In accordance with the image signal, the control voltage application circuit 8 applies + 50V to the control electrode 4 corresponding to the image portion via the control element 7 provided on the lower surface of the toner case 11 of the toner cartridge 10. Is applied. As a result, an electric force line from the control electrode 4 toward the toner carrying roller 14 is formed in the vicinity of the aperture 6 corresponding to the image portion due to the potential difference between the control electrode 4 and the toner carrying roller 14. Therefore, the negatively charged toner 16 receives an electrostatic force in the direction of higher electric potential, passes through the aperture 6 from the toner carrying roller 14 and is drawn out to the control electrode 4 side. The pulled-out toner 16 further flies toward the image recording medium 20 by an electric field formed between the image recording medium 20 and the aperture electrode body 1 by the voltage of +1 kV applied to the back electrode plate 22. , Are deposited on the image recording medium 20 to form pixels.

Further, the control electrode 4 corresponding to the non-image part
Is controlled by the control voltage applying circuit 8 to control the control element 7,
Maintained at the voltage of. As a result, the toner carrying roller 14
An electric field is not formed between the control electrode 4 and the control electrode 4, and the toner 16 on the toner carrying roller 14 does not receive the electrostatic force and therefore does not pass through the aperture 6.

When one row of pixels is formed by the toner 16 on the surface of the image recording medium 20, the central controller (not shown) rotates the drive motor (not shown) to move the transport rollers 19a, 19b. When rotated, the image recording medium 20 is conveyed by one pixel in the direction of arrow A. Then, the toner image is formed on the entire surface of the image recording medium 20 by repeating the above image forming process. After that, the image recording medium 20 on which the toner image is formed is conveyed by the conveying roller 19
a, 19 b, and another transport roller (not shown) transports the heat roller 2 to the fixing device 26.
It is heat-fixed by 6b.

By repeating the image forming operation according to the above process, the toner images are successively formed. Here, when the toner 16 in the toner reservoir 21 is used up, the toner cartridge 10 is replaced with the image forming apparatus 5.
The toner cartridge 10 is removed from the main body frame (not shown) and replaced with a new toner cartridge 10.

In this case, the connector 9 fitted to the edge portion 2a of the insulating sheet 2 of the aperture electrode body 1 is removed, and a connector (not shown) provided between the control voltage applying circuit 8 and the control element 7 is removed. And the toner cartridge 10 is replaced. Then, the new toner cartridge 10 is fixed on the main body frame of the image forming apparatus 50,
In the reverse order of the above, the connector 9 is fitted to the edge portion 2a of the insulating sheet 2 of the aperture electrode body 1, and the control voltage applying circuit 8 and the control element 7 are connected by a connector (not shown).

Therefore, the control element 7 fixed to the lower surface of the toner case 11 is the toner cartridge 10
Every time the toner cartridge 10 is replaced, the toner cartridge 10 is replaced with a new control element 7. Therefore, the damaged control element 7 or the deteriorated control element 7 is replaced with a new control element 7 every time the toner cartridge is replaced, and the control element 7 can be easily replaced.
Due to the above defect, there is no possibility that pixels will be missing or fog on the image recording medium 20.

The present invention is not limited to the image forming apparatus of this embodiment described in detail above, and various modifications can be made without departing from the spirit of the invention.

For example, the image forming apparatus 50 of the above embodiment.
Then, although the aperture electrode body 1 is fixed to a body frame (not shown), as shown in FIG.
Is fixed to the toner case 11, and the toner cartridge 10
It may be configured integrally with. In this case, in order to make the contact between the aperture 6 of the aperture electrode body 1 and the toner carrying roller 14 uniform, it is necessary to fix the aperture electrode body 1 to the opening of the toner case 11 of the toner cartridge 10 while applying tension. is there. In this way, the aperture electrode body 1 also
Each time the toner cartridge 10 is detached and replaced, it can be easily replaced as a unit. At this time, if the size of the toner reservoir 21 of the toner cartridge 10 is adjusted and the amount of the stored toner 16 is adjusted, the service life of the aperture electrode body 1 and the service life of the toner cartridge 10 can be matched. You can also

Further, in this case, the control element 7 for applying the control voltage to each control electrode 4 is provided not on the toner case 11 but on the toner case 11.
If it is provided on the insulating sheet 2 of the aperture electrode body 1, the conventional aperture electrode body 1 can be used.

Further, the size of the toner reservoir 21 of the toner cartridge 10 may be adjusted to adjust the amount of the stored toner 16 so that the service life of the control element 7 and the service life of the toner cartridge 10 are matched. it can.

In the above embodiment, the control element 7 is arranged on the toner case 11 of the toner cartridge 10. However, when only the toner 16 is replenished by exchanging the toner box, the control element is installed in the toner box. 7 may be provided.

In the above embodiment, the control element 7 is
Although it is provided on the surface of the toner case 11 of the toner cartridge 10, a cover for protecting the control element 7 may be provided on the toner case 11.

Further, the control element 7 may be provided inside the toner cartridge 10, and the connector may be provided on the toner case 11.

Further, if the aperture electrode body 1 and the toner cartridge 10 are constructed so as to be attachable / detachable with a connector, the connection between the control element 7 and the conductor 5 of the control electrode 4 becomes easy.

Further, the image forming apparatus 50 of the above embodiment.
Then, the control voltage of the control electrode 4 of the aperture corresponding to the non-image portion is set to 0V, but this may be a negative voltage of about −30V, for example. In this case, an image with less fogging can be obtained.

Although the aperture electrode body is used as the toner flow control means in the above embodiment, it is also possible to use a mesh-shaped electrode body as described in the specification of US Pat. No. 5,036,341. Is.

[0057]

As is apparent from the above description, in the image forming apparatus according to the first aspect of the invention, the detachable toner cartridge is provided with the control element for applying the voltage to the control electrode of the electrode array. Therefore, every time the toner cartridge is replaced, the control element can be replaced together with the toner cartridge. Therefore, it becomes possible to replace the control element by replacing the toner cartridge, and it becomes unnecessary to replace the control element which has become unnecessary. Further, it is possible to prevent the occurrence of defects in the image due to the unnecessary control element.

In the image forming apparatus according to the second aspect of the invention, the control element provided in the toner cartridge and the control electrode of the electrode array can be easily connected by the connector.

Further, in the image forming apparatus of the invention described in claim 3, the control element is provided on the electrode array, and the electrode array is mounted on the detachable toner cartridge, so that the toner cartridge is replaced. For each, not only the control element, but also the entire electrode array can be replaced. Therefore, since the control element and the electrode array are exchanged by exchanging the toner cartridge, not only the defect of the control element but also the defect of the image due to the clogging of the hole of the electrode array can be prevented.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of an image forming apparatus that is an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of an aperture electrode body used in the image forming apparatus which is an embodiment of the present invention.

FIG. 3 is a diagram showing a positional relationship between an aperture electrode body and a toner carrying roller of this embodiment.

FIG. 4 is a diagram showing a configuration of an image forming apparatus which is another embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a conventional image forming apparatus.

FIG. 6 is a perspective view of an aperture electrode body used in a conventional image forming apparatus.

[Explanation of symbols]

 1 Aperture Electrode 2 Insulation Sheet 4 Control Electrode 5 Conductor 6 Aperture 7 Control Element 9 Connector 8 Control Voltage Application Circuit 10 Toner Cartridge 11 Toner Case 14 Toner Carrying Roller

Claims (3)

[Claims] 1. An electrode array having a plurality of holes for allowing charged toner to pass therethrough and having a control electrode provided for each hole to control passage of the toner, and an electrode array provided on the electrode array. A removable toner cartridge that stores toner supplied to the hole, and a control element that is provided in the toner cartridge and that controls the application of voltage to the control electrode when the toner cartridge is mounted Image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the control electrode and the control element are connected by a connector. 3. An electrode array having a plurality of holes for passing charged toner and having a control electrode for controlling the passage of the toner, provided for each hole, and an electrode array provided on the electrode array. A control element for controlling application of voltage to the control electrode, and a detachable toner cartridge on which the electrode array is mounted and which stores toner to be supplied to holes provided in the electrode array. An image forming apparatus having.