JPH08123135A - Corona electrifying device - Google Patents

Abstract

PURPOSE: To integrate parts so as to reduce the number of parts and reduce cost by integrally forming a tooth-shaped electrode plate and a control grid plate and separating them after attaching either of them. CONSTITUTION: The tooth-shaped electrode plate 1 and the control grid plate 6 are integrated, the plate 1 is bent and the fixing pin 22a of a supporting block 21b is fitted in a hole for fixing, and a bent part 7 is bent along a supporting member, then the fixing pin 23a of the supporting block 21b is fitted in the hole for fixing. The head of each fixing pin is thermally caulked by ultrasonic welding so as to fix a conductive thin plate to the supporting member. By fixing the supporting member to which the conductive thin plate is attached on a fixing base, cutting a connection part provided on the conductive thin plate by a pin for cutting 60, and separating the plate 1 and the grid late 6, the corona electrifying device 200 is completed. Therefore, the defect of the parts by the damage and the breakage of the tooth-shaped electrode 1a caused by handling in case of assembly is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corona discharge type charging device using a non-contact type sawtooth electrode used for the purpose of charging a photoconductor in an electrophotographic image forming apparatus.

[0002]

2. Description of the Related Art Heretofore, as a corona discharge type charging device of this type, a wire discharge type (corotron, scorotron,
Dicorotron etc.) and pin discharge method (pin electrode type, serrated electrode type, etc.). The latter has recently come to be used in electrophotographic copying machines, printers and the like due to low ozone generation. In particular, a charging device having a structure using an electrode plate in which a plurality of serrated electrode parts are provided on one thin plate member is disclosed.
No. 63-15272, or a charging device having a structure using an electrode plate in which a plurality of sawtooth electrode parts are provided on one thin plate-shaped member, which simplifies the assembly work. It is disclosed by Kaihei 5-45999.

[0003]

However, in the conventional charging device having a structure using an electrode plate in which a plurality of sawtooth electrode portions are provided on one thin plate member, the sawtooth electrode plate itself is used. Focusing only on assembly workability and cost reduction, there was nothing that considered improvement of assembly workability and cost reduction when the corona charging device was viewed from the whole.

Further, if such independent thin plate-shaped sawtooth electrode plates and grid plates are individually assembled into a large number of blocks, not only the number of assembling steps but also the handling at the time of assembling is required. Serrated electrode plate,
In particular, parts with defects such as scratches and breakage of the sawtooth electrode, and the highly accurate positioning required for the sawtooth electrode part of the sawtooth electrode plate and the grid to maintain the uniformity of charging can be performed. There was a problem such as not being.

The present invention solves such problems and
Considering the entire corona charging device, by integrating the parts, the number of parts is greatly reduced to reduce the cost, the assembly is easy, the assembly man-hours are small, and the assembly accuracy is high. It is an object of the present invention to provide a corona charging device that can be maintained and has stable discharge performance.

[0006]

The above object is to integrally form a sawtooth electrode plate having a plurality of sawtooth electrodes on a conductive thin plate and a control grid plate, and to form the sawtooth electrodes on a supporting member. The corona charging device is characterized in that the sawtooth electrode plate and the control grid plate are separated after the plate or at least one of the control grid plates is attached. Further, a sawtooth electrode plate and a control grid plate are integrally formed on a conductive thin plate, and the corona charging device is formed by bending the conductive thin plate. An electrode and the control grid plate are arranged in parallel, and the grid surface of the control grid plate is arranged substantially orthogonal to the extension line of the sawtooth electrode plate. To be done. Further, the conductive thin plate is formed on both ends of the control grid plate after the corona charging device is assembled, and at least one surface thereof is a side plate of the corona charging device. Is also a preferred embodiment.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the corona charging device of the present invention will be described with reference to FIGS. FIG. 1 is a processing diagram of a conductive thin plate of the first embodiment, FIG. 2 is a perspective view showing an assembly of the conductive thin plate to a support member, and FIG. 3 is a connecting portion of a corona charging device. It is sectional drawing when cutting.

Reference numeral 10 denotes an electrode member which is a conductive thin plate made by etching a stainless steel plate having a plate thickness of 0.1 mm, for example, and has a sawtooth shape having a plurality of sawtooth electrodes 1a on one conductive thin plate 10. It is made by integrally forming the electrode plate 1 and the control grid plate 6, fixing holes 2a, 2b, 2c are provided in the sawtooth electrode plate 1, and both ends of the sawtooth electrode plate 1 are provided. The connecting parts 5a and 5b, and the bent part 7 are
End fixing holes 3a and 3b and fixing holes 4a, 4b and 4c of the bent portion 7 are provided at both ends thereof, respectively. Reference numeral 8 is a plane portion of the connection between the sawtooth electrode plate 1 and the control grid plate 6.

Reference numeral 20 is a conductive thin plate made of an insulating resin.
10 support members, support blocks 21a, 21c at both ends
And a support block 21b for fixing the conductive thin plate 10 and a support block 21d for support, which are integrated by an adhesive or a fitting portion (not shown). The support blocks 21a and 21c at both ends are provided with end fixing pins 23a and 23b.
And escape holes 25a and 25b for cutting pins of the connecting portion, which will be described later, are provided respectively. Further, the support block 21b is provided with fixing pins 22a, 22b, 22c of the sawtooth electrode plate 1 and fixing pins 24a, 24b, 24c of the bent portion. The support block 21d for support has a notch 26
Is provided.

A conductive thin plate 10 is attached to an integrated supporting member 20.
The corona charging device 200 is formed while bending.
The dotted line in FIG. 1 indicates a fold line. The sawtooth electrode plate 1 of the conductive thin plate 10 is bent, and the fixing holes 2a, 2 of the sawtooth electrode plate 1 are bent.
b and 2c are fixed pins 22 of the support block 21b, respectively.
The flat surface portion 8 of the connection between the sawtooth electrode plate 1 and the control grid plate 6, the control grid plate 6, and the bent portion 7 at the end, which are fitted into the a, 22b, and 22c, are bent along the support member 20, Support blocks 21 are provided with fixing holes 3a and 3b at the ends.
to the fixing pins 23a and 23b of a and 21c, and fixing holes 4
a, 4b, 4c are fixed pins 24a, 24 of the support block 21b
Insert into b and 24c. The conductive thin plate 10 is fixed to the support member 20 by heat-sealing the heads of the respective fixing pins by ultrasonic welding or the like. The support member 20 to which the conductive thin plate 10 is attached is fixed to a fixing base (not shown), and the connecting portion 5 provided on the conductive thin plate 10 is fixed.
a and 5b are cut by a cutting pin 60 to separate the sawtooth electrode plate 1 and the control grid plate 6 from each other, and the corona charging device 20
0 is completed. The connecting flat portion 8 is a support block 21.
It functions as a side plate of the corona charging device through the notch 26 of d. When the conductive thin plate 10 is bent, the sawtooth electrode 1a at the tip of the sawtooth electrode plate 1 and the control grid plate 6 are arranged in parallel, and the sawtooth electrode plate 1
On the extension line of the grid surface 6a of the control grid plate 6,
They are arranged so as to be orthogonal or substantially orthogonal (not shown).

When used in an image forming apparatus as a corona charging device, a DC voltage of 2 to 6 KV is applied to the saw-toothed electrode plate 1 and a flat surface portion 8 which is a control grid plate 6 or a side plate is A bias voltage of 500 to 1000 V is applied.

Next, another embodiment of the corona charging device of the present invention will be described with reference to FIGS. 4 is a processing diagram of a conductive thin plate of another embodiment, FIG. 5 is a perspective view showing an assembly of the conductive thin plate of FIG. 4 to a support member, and FIG. 6 is a corona of FIG. It is sectional drawing when the connection part of a charging device was cut.

Reference numeral 100 denotes an electrode member which is a conductive thin plate formed by etching a stainless steel plate having a plate thickness of 0.1 mm, for example, and a plurality of serrated electrodes 101a are provided on one conductive thin plate 100.
The sawtooth electrode plate 101 and the control grid plate 106 are integrally formed, and the sawtooth electrode plate 101
Fixing holes 102a, 102b, 102c are provided on the bottom surface, and connection portions 105a, 105b, 105c, 105d are provided on the lower end portion of the sawtooth electrode plate 101.
However, the bent portion 107 has fixing holes 103 at both ends thereof.
a and 103b are provided. Reference numerals 108a and 108b are plane portions of the connection between the sawtooth electrode plate 101 and the control grid plate 106. The connecting flat portion 108b is provided with connecting portions 112a and 112b with the control grid plate 106, and the bent portion 107 is also provided with connecting portions 113a and 113b with the control grid plate 106. At both ends of the control grid plate 106, the control grid plate 1
Holes 119a and 119b for attaching 06 are provided.

Reference numeral 120 denotes a support member of the conductive thin plate 100 made of an insulating resin, and has support blocks 121a at both ends,
Support block 121 for fixing 121c and the conductive thin plate 100
b, and is integrated by an adhesive or a fitting portion (not shown). In the support block 121a at the end portion, the fixing pin 123a of the bent portion, the fixing pin 129a of the control grid plate 106, and the escape holes 132a and 133a of the cutting pin of the connecting portion.
In addition, the support block 121c is provided with a fixing pin 123b of the bent portion, a fixing pin 129b of the control grid plate 106, and escape holes 132b and 133b of the cutting pin of the connecting portion. Further, the sawtooth electrode plate 1 is provided on the support block 121b.
A fixed pin 122a, 122b, 122c of 01, escape holes 125a, 125b, 125c, 125d for cutting the connecting portion, and a cutout portion 126 are provided, respectively.

The conductive thin plate 1 is attached to the integrated support member 120.
The corona charging device 300 is formed while bending 00. The dotted line in FIG. 3 indicates the folding line. Bending the sawtooth electrode plate 101 of the conductive thin plate 100 to fix the sawtooth electrode plate 101.
102a, 102b and 102c are respectively supported by a support block 121b.
Of the sawtooth electrode plate 101 and the control grid plate 106, which are fitted into the fixing pins 122a, 122b, 122c of the flat plate 108a, 1
08b, control grid plate 106, end bent portion 107
Is bent along the support member 120, the holes 119a and 119b of the control grid plate 106 are fixed to the fixing pins 129a and 129b, and the fixing holes 103a and 103b at the end of the bent portion 107 are fixed to the support blocks 121a and 121c. Fit into pins 123a and 123b.
The conductive thin plate 100 is fixed to the support member 120 by heat-bonding the heads of the respective fixing pins by ultrasonic welding or the like. The supporting member 120 having the conductive thin plate 100 attached thereto is fixed to a fixing base (not shown), and the connecting portions 105a, 105b, 105 provided on the conductive thin plate 100 are fixed.
c and 105d by a cutting pin 160, connecting portions 112a and 112b between the connecting flat portion 108b and the control grid plate 106, and connecting portions 11 between the bent portion 107 and the control grid plate 106.
3a and 113b are cut by cutting pins 161, 162 to form a sawtooth electrode plate 101, a control grid plate 106, and a bent portion 107 that functions as a side plate of the corona charging device.
The flat portion 108 of the joint that also functions as a side plate
Corona charging device by separating b and b into independent members
300 is completed. Through the bent portion 107 and the cutout portion 126 of the support block 121b, the connecting flat portion 108b is formed.
Acts as a side plate.

When the conductive thin plate 100 is bent,
The sawtooth electrode 101a at the tip of the sawtooth electrode plate 101 and the control grid plate 106 are arranged in parallel, and the sawtooth electrode plate 101
On the extension line of the grid surface 106a of the control grid plate 106
However, they are arranged so as to be orthogonal (or not shown) at a right angle.

When used as a corona charging device,
A DC voltage of 2 to 6 KV is applied to the saw-toothed electrode plate 101, a DC voltage of 400 to 600 V is applied to the control grid plate 106, and a bias voltage of 500 is applied to the bent portion 107 which is the side plate and the connecting flat portion 108b. A voltage of ~ 1000V is applied.

In any of the above-mentioned embodiments, it is either a case where the conductive thin plate is assembled while being bent to the supporting member, or the bent conductive thin plate is attached to the supporting member. It is also possible to perform thermal caulking and disconnection of the connection part individually or simultaneously in one step. At the same time, it is possible to simultaneously perform thermal caulking and disconnection of the connection portion.

[0019]

According to the first or second aspect of the present invention, the sawtooth electrode plate and the control grid plate are integrally molded on the conductive thin plate to reduce the number of parts, and the sawtooth electrode plate is provided on the supporting member. By cutting the control grid plate and the control grid plate after they are integrated and fixed, it is possible to reduce the number of assembly steps by individually assembling each independent thin plate sawtooth electrode plate, grid plate, etc. into many blocks. Not only
Saw-toothed electrode plate due to handling during assembly, especially to reduce parts defects due to scratches or damage to the sawtoothed electrode plate, and further to achieve highly accurate positioning of the sawtoothed electrode plate and the control grid plate. It has become possible to provide a corona charging device which can improve the uniformity of charging by highly accurate positioning.

According to the third or fourth aspect of the invention, the corona charging device is formed by integrally forming the portion which functions as a side plate on the conductive thin plate, and in particular, the sawtooth electrode is provided on the supporting member. By cutting after fixing integrally with the plate and control grid plate, not only the above-mentioned increase in the number of assembly steps is reduced, but also the sawtooth electrode plate, especially the sawtooth-shaped electrode is scratched or damaged due to the handling at the time of assembly. The provision of a corona charging device that further enhances the effects of reducing the number of defective parts due to such factors as the positioning of the sawtooth electrode of the sawtooth electrode plate and the control grid plate with high accuracy. Made possible.

[Brief description of drawings]

FIG. 1 is a processing diagram of a conductive thin plate according to a first embodiment.

FIG. 2 is a perspective view showing an assembly of a conductive thin plate to a support member.

FIG. 3 is a cross-sectional view of the corona charging device when a connecting portion is cut off.

FIG. 4 is a processing diagram of a conductive thin plate of another embodiment.

5 is a perspective view showing the assembly of the conductive thin plate of FIG. 4 to a support member.

6 is a cross-sectional view of the corona charging device of FIG. 4 when the connecting portion is cut off.

[Explanation of symbols]

1,101 Sawtooth electrode plate 6,106 Control grid plate 7,107 Folding part 8,108a, 108b Flat part of joint 10,100 Conductive thin plate 20,120 Support member 21a, 21b, 21c, 21d, 121a, 121b, 121c Support block 26,126 Notch 60,160,161,162 Cutting pin 200,300 Corona charging device

Claims (4)

[Claims] 1. An electrode sawtooth electrode plate having a plurality of sawtooth electrodes and a control grid plate are integrally formed on a conductive thin plate, and the sawtooth electrode plate or the control grid plate is formed on a support member. A corona charging device, characterized in that the saw-toothed electrode plate and the control grid plate are separated after at least one of them is attached. 2. A sawtooth electrode plate and a control grid plate are integrally formed on a conductive thin plate, and the conductive thin plate is bent to form a corona charging device. A tip portion of the sawtooth electrode plate. Corona charging characterized in that the sawtooth electrode and the control grid plate are arranged in parallel, and the grid surface of the control grid plate is arranged substantially orthogonal to the extension line of the sawtooth electrode plate. apparatus. 3. The corona charging device according to claim 1, wherein at least one surface formed on both ends of the control grid plate serves as a side plate of the corona charging device. 4. The corona charging device according to claim 3, wherein the support member is provided with a notch portion for forming a side plate.