JPS6315879Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a corona discharge device, particularly for various purposes such as charging or eliminating static electricity on the surface of a photoreceptor, or transferring a developed image (toner image) formed on the surface of a photoreceptor onto copy paper. The present invention relates to a corona discharge device suitable for use in an electrostatic copying machine.

As is well known to those skilled in the art, corona discharge devices are used in electrostatographic reproduction machines for a variety of purposes.
At least one, and usually more than one, corona discharge device is located in position within the electrostatographic reproduction machine housing.

Therefore, a corona discharge device generally includes a corona discharge device main body that includes a shield case having a rear wall and both side walls hanging from both side edges of the rear wall, and a discharge wire stretched within the shield case. However, when arranging such a corona discharger main body at a required position within the electrostatic copying machine housing, it is possible to quickly and easily clean or replace the discharge wire in the event that the discharge wire becomes contaminated or damaged. In order to be able to carry out the necessary tasks, it is important to attach the device in such a way that it can be removed quickly and easily if necessary. Therefore, in the conventional corona discharge device, a guide rail having receiving grooves extending in the longitudinal direction on both sides is fixed at a predetermined position in the electrostatic copying machine housing, and the outer surface of the rear wall of the shield case of the corona discharge device body is By fixing an engaging rail having engaging parts on both sides and inserting the engaging part of the engaging rail into the receiving groove of the guide rail, the corona discharger main body can be freely attached to and detached from the guide rail. It was installed on. In such a conventional corona discharge device, by simply pulling the corona discharger body in the longitudinal direction, the engaging portion of the engaging rail slides within the receiving groove of the guide rail and is removed from the receiving groove. Therefore, the corona discharger body is detached from the guide rail, and therefore the corona discharger body can be quickly and easily detached from a desired position in the electrostatic copying machine housing to clean the discharge wire or to clean the discharge wire or exchange can be carried out.

However, in the conventional corona discharge device as described above, the engagement rail is manufactured separately from the shield case of the main body of the corona discharge device, and is attached to the outer surface of the rear wall of the shield case by screws or welding. The drawback is that the corona discharger body has to be fixed in place, which makes the manufacturing cost of the corona discharger body relatively high.

Furthermore, it should be noted that in the conventional corona discharge device as described above, ozone generated due to the corona discharge current from the discharge wire, especially the negative corona discharge current, remains in the shield case. There is a problem to be solved in that there is a tendency that such accumulated ozone may have an adverse effect on photoreceptors and the like.

The present invention has been made in view of the above facts, and its main purpose is to provide a new and excellent corona discharge device that skillfully solves the above-mentioned drawbacks and problems found in conventional corona discharge devices.

As a result of intensive research, the inventors of the present invention have determined that at least one of the two side walls or a portion of the rear wall of the shield case of the main body of the corona discharger is made to protrude laterally outward on each side of the shield case of the main body of the corona discharger. If one protruding piece is formed, the corona discharger body can be attached to the guide rail so that it can be quickly and easily removed as needed by inserting the protruding piece into the receiving groove of the guide rail. It is therefore possible to omit the engagement rail fixed to the outer surface of the rear wall of the corona discharger body in conventional corona discharge devices, thus significantly reducing manufacturing costs, and also surprisingly In particular, the openings inevitably created in the shield case by the formation of the protruding piece described above greatly enhance air circulation inside and outside the shield case, thus effectively preventing ozone from accumulating within the shield case. It was found that it was suppressed.

That is, according to the present invention, there is provided a shield case having a guide rail fixed at a predetermined position and having receiving grooves extending in the longitudinal direction on both sides, a rear wall and both side walls hanging from both side edges of the rear wall, and the shield. In a corona discharge device including a corona discharger main body having a discharge wire stretched inside a case; At least one protruding piece is formed by protruding from the guide rail, and by inserting the protruding piece into the receiving groove of the guide rail, the corona discharger main body is detachably attached to the guide rail. Further, an opening is formed in each of the side walls or the rear wall by forming the protruding piece, and the inside and outside of the shield case are communicated through the opening. Equipment is provided.

Hereinafter, a specific example of a corona discharge device constructed in accordance with the present invention will be described in more detail with reference to the accompanying drawings.

Referring to FIG. 1, the illustrated corona discharge device, generally designated by the numeral 2, comprises a guide rail 4;
Corona discharger main body 6 and further protective cover 8
It is equipped with

The guide rail 4 has both side walls 12 hanging from both side edges of the base wall 10 extending in the longitudinal direction, and a locking wall 14 extending inward by a certain length from the lower end of each side wall 12. A receiving groove 16 extending in the longitudinal direction is defined by the side portion of the base wall 10, the side wall 12, and the locking wall 14, and is formed in each of the side portions. A suitable spring member 18, such as a leaf spring, is provided on the inner surface of the base wall 10.

The corona discharger main body 6 includes a shield case 20 and a discharge wire 2 stretched inside the shield case 20.
2. The shield case 20 has a rear wall 24 extending in the longitudinal direction and both side walls 26 hanging from both side edges of the rear wall 24, and the front surface thereof is open over the entire width. The discharge wire 22 is stretched as required within the shield case 20 by a discharge wire support 28 and a set screw 30 fixed to both ends of the inner surface of the rear wall 24 of the shield case 20. When a corona discharger main body 6 is attached to one end of the shield case 20 (the left end in FIG. 1) at a desired position in an electrostatic copying machine housing (not shown) as will be explained later, the electrostatic copying machine is installed. A plug 32 is provided which is inserted into a socket (not shown) provided within the housing to connect the discharge wire 22 to the power supply circuit. Also,
At the other end of the shield case 20 (the right end in FIG. 1), there is a gripping piece 34 for gripping the corona discharger body 6 when it is installed in a desired position in the electrostatic copying machine housing, for example, and when it is removed from there. It is provided.

In the corona discharge device 2 constructed according to the present invention, a shield case 2 is provided on each of both sides of the shield case 20 of the corona discharge device body 6 described above.
At least one side wall 20 or a portion of the rear wall 24 of
It is important that at least one protruding piece 36 and at least one opening 38 are formed.

In the illustrated example, the shield case 20
By causing a portion of the side wall 26 to protrude laterally outward at two positions spaced apart from each other in the longitudinal direction, more specifically, at positions near both ends of each of the side walls 26, Two protruding pieces 36 and two corresponding openings 38 are formed. Projecting piece 36
The opening 38 may have any suitable shape, but is preferably rectangular and elongated in the longitudinal direction as shown. Furthermore, it is advantageous for the protruding piece 36 to protrude laterally outward so as to be substantially flush with the rear wall of the shield case 20, as shown in the drawings.
On the other hand, in the specific example shown, the lower edge of the opening 38 is located at the middle part of the side wall 26 in the vertical direction;
If desired, aperture 38 can extend downwardly to the lower edge of sidewall 26.

The protruding pieces 36 and openings 38 on both side walls 26 of the shield case 20 can be conveniently formed, for example, by manufacturing the shield case 20 in the following procedure. That is, three sides of the protruding piece 36 and the opening 38 (i.e., the protruding edge and both side edges of the protruding piece 36 and the lower edge and both side edges of the opening 38) are defined at the required positions of the plate-like material for manufacturing the shield case 20. The plate-shaped material is then bent to bend both sides of the plate-shaped material downward, thus defining the rear wall 24 by the lateral center of the plate-shaped material, and Both side walls 26 are defined by the downwardly bent side portions of the shaped material. During the bending process, the area defined by the cutting line is left as is without being bent downward, so that a protrusion laterally protrudes from the side wall 26 that is substantially coplanar with the rear wall 24. The projecting piece 3 is formed on the side wall 26 at the same time as forming the piece 36.
6 is formed.

Next, explaining the protective cover 8, the illustrated protective cover 8 includes a bottom wall 40 that has a width slightly larger than the width of the shield case 20 and extends over approximately the same length as the entire length of the shield case 20; It has both side walls 42 standing upright from both side edges of the bottom wall 40. The bottom wall 40 is formed with an elongated discharge width regulating opening 44 extending in the longitudinal direction leaving both ends of the bottom wall 40 open. The illustrated protective cover 8 further includes connecting pieces 4 hanging from both ends of the bottom wall 40.
6, through which a fastener (not shown) such as a set screw is used to secure the protective cover 8 at a desired position within the electrostatic copying machine housing. Hole 4
8 is formed.

Next, a method for mounting the corona discharge device 2 as described above at a predetermined position within, for example, an electrostatic copying machine will be described.

For example, for charging or eliminating static electricity on a photoreceptor disposed on the circumferential surface of a rotating drum 50 (only a part of which is shown in FIG. 2) rotatably mounted in an electrostatic copying machine housing. When using the above-described corona discharge device 2 as the static elimination corona discharge device, it is necessary to install it at a predetermined position close to the circumferential surface of the rotating drum 50, as shown in FIG. In such a case, the guide rail 4 is fixed behind the part of the electrostatic copying machine housing where the corona discharger main body 6 is to be mounted, and the guide rail 4 is fixed between the part where the corona discharger main body 6 is to be mounted and the rotary drum 5.
The protective cover 8 is fixed such that the bottom wall 40 of the protective cover 8 is located between the peripheral surface of the protective cover 8 and the peripheral surface of the protective cover 8. The guide rail 4 can be fixed, for example, by integrally providing locking protrusions (not shown) at both ends of the guide rail 4, and passing through the locking protrusions into the electrostatic copier housing. By screwing a set screw into a support member (not shown),
Alternatively, this can be accomplished by forming a suitable hole (not shown) in the base wall 10 of the guide rail 4 and screwing a set screw into the support member through the hole. In addition, fixing of the protective cover 8 is as follows.
By screwing a set screw into a suitable support member (not shown) provided in the electrostatic copying machine housing through a hole 48 formed in a connecting piece 46 provided at both ends thereof. can be carried out.

After fixing the guide rail 4 and the protective cover 8 at the required positions as described above, the corona discharger main body 6 is defined between the two by the guide rail 4 and the protective cover 8, with the left end as the front end in FIG. As shown in FIG. 2, the protruding pieces 36 formed on both side walls 26 of the shield case 20 are positioned in the receiving grooves 16 formed on both sides of the guide rail 4. Next, the corona discharger main body 6 is advanced along the guide rail 4 to a desired position by gripping the gripping piece 34 attached to the rear end (the right end in FIG. 1) of the shield case 20, and the corona discharger is thus released. Attach the electrical appliance main body 6 to the required position. The spring member 18 provided on the inner surface of the base wall 10 of the guide rail 4 is connected to the shield case 20.
Projecting pieces 36 elastically abut against the outer surface of the rear wall 24 to bias the shield case 20 downward, and are thus formed on both side walls 26 of the shield case 20.
is elastically pressed against the locking wall 14 of the guide rail 4,
It elastically maintains the corona discharger body 6 in the required position relative to the guide rail 4.

When the corona discharger body 6 is removed for cleaning or replacing the discharge wire 22, the shield case 2 is removed.
Grip the gripping piece 34 attached to the front end of 0,
All that is required is to pull out the corona discharger main body 6.

As described above, according to the illustrated corona discharge device 2 constructed according to the present invention, both side walls 26 of the shield case 20 of the corona discharge device main body 6
The protruding piece 36 formed on the guide rail 4 is inserted into the receiving groove 1 of the guide rail 4.
6, the corona discharger body 6 is mounted in the desired manner on the guide rail 4 so that it can be quickly and easily removed if necessary. Therefore, unlike conventional corona discharge devices, there is no need to fix a separately manufactured engagement rail to the outer surface of the rear wall 24 of the shield case 20 of the corona discharge device main body 6, and the manufacturing cost is lower than that of conventional corona discharge devices. can be considerably reduced. Also, it is particularly noteworthy that according to the illustrated corona discharge device 2 constructed in accordance with the present invention,
By forming the protruding pieces 36 on both side walls 26 of the shield case 20 of the corona discharger main body 6, openings 38 are inevitably formed on both side walls 26 of the shield case 20. As a result, air circulation inside and outside the shield case 20 is greatly improved. Therefore, the tendency of ozone generated due to the corona discharge current from the discharge wire 22 of the corona discharger main body 6, particularly the negative corona discharge current, to remain in the shield case 20 is effectively prevented or suppressed. Therefore, problems such as ozone staying in the shield case 20 having an adverse effect on the photoreceptor disposed on the circumferential surface of the rotating drum 50 and causing it to deteriorate can be sufficiently avoided.

In the illustrated example, the corona discharge device 2 includes a protective cover 8 in addition to the guide rail 4 and the corona discharge device main body 6, but if desired,
The protective cover 8 can be omitted. However, using the protective cover 8 provides the following advantages. That is, for example, when installing the corona discharger main body 6 at a predetermined position in the electrostatic copying machine housing, the protruding pieces 36 formed on both side walls 26 of the shield case 20 are already attached to the electrostatic copying machine housing, as described above. The corona discharger body 6 is positioned within the receiving groove 16 of the guide rail 4 fixed at a predetermined position within the
However, due to an operator's mistake, the corona discharger main body 6 may be moved forward without positioning the projecting piece 36 within the receiving groove 16.
If such an operation error occurs, remove the protective cover 8.
When there is no corona discharger, the corners such as the front lower edges of both side walls 26 of the shield case 20 of the corona discharger main body 6 are brought into contact with, for example, a photoreceptor disposed on the circumferential surface of the rotating drum 50, and in this state, the corona is removed. This may cause the discharger main body 6 to move forward.
In this case, as is easily understood, an unacceptable situation arises in which a relatively expensive photoreceptor is damaged and rendered unusable. However, if the protective cover 8 is disposed between the area where the corona discharger main body 6 is to be attached and the circumferential surface of the rotating drum 50, the side walls of the shield case 20 may be damaged due to an operator's mistake. 2
Even if the corona discharger main body 6 is moved forward without positioning the protruding piece 36 formed in the guide rail 4 in the receiving groove 16 of the guide rail 4, the bottom of the front end of the both side walls 26 of the shield case 20 of the corona discharger main body 6 Corners such as edges are only brought into contact with the protective cover 8 and are not brought into contact with the photoreceptor disposed on the circumferential surface of the rotating drum 50.
Therefore, the occurrence of an unacceptable situation in which a relatively expensive photoreceptor is damaged and rendered unusable due to an operational error when installing the corona discharger main body 6 can be reliably prevented. Ru.

Furthermore, when the protective cover 8 is used, as can be easily understood from FIG. The corona discharge current passes through a discharge width regulating opening 44 formed in the bottom wall 40 of the protective cover 8, and the width of the corona discharge current applied to the photoreceptor is regulated by the width of the discharge width regulating opening 44. Ru. Therefore, as in the case of a conventional corona discharge device, each of the lower ends of the side walls 26 of the shield case 20 of the corona discharger main body 6 is provided with an extension extending inwardly therefrom, and the shield is shielded by the extension. There is no need to narrow the opening width at the front of the case 20 to a predetermined value, and the shield case 20
The front surface of the holder can be opened over its entire width as in the illustrated embodiment. Therefore, the work of tensioning or replacing the discharge wire 22 can be easily performed through the front surface of the shield case 22, which is opened over the entire width.

In the specific example described above, the protrusion piece 36 and the opening 38 are formed by making each part of the shield case 20 of the corona discharger main body 6 protrude laterally outward, but if desired, the protrusion piece 36 and the opening 38 are formed. Instead, as shown in FIG. 3, the protrusion piece 36 and the opening 38 are formed by making a portion of each side of the rear wall 24 of the shield case 20 protrude laterally outward. You can also. In this case, air circulation inside and outside the shield case 20 through the openings 38 located on both sides of the rear wall 24 is carried out by the guide rail 4.
Therefore, it is desirable to additionally form an opening 52 in the base wall 10 of the guide rail 4 corresponding to the opening 38.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing a specific example of a corona discharge device constructed according to the present invention. Figure 2 shows
FIG. 2 is a sectional view showing a state in which the corona discharge device shown in FIG. 1 is mounted as a charging corona discharge device in close proximity to the circumferential surface of a rotating drum. FIG. 3 shows a modification of a corona discharge device constructed in accordance with the present invention. Sectional view similar to FIG. 2. 2... Corona discharge device, 4... Guide rail, 6
... Corona discharger body, 8 ... Protective cover, 16
... Receiving groove, 20 ... Shield case, 22 ... Discharge wire, 24 ... Rear wall of shield case, 26 ...
Side wall of shield case, 36...Protruding piece, 38...
...Aperture, 44...Discharge width regulation aperture.

Claims (1)

[Claims for Utility Model Registration] 1. A shield case having a guide rail that is fixed at a predetermined position and has receiving grooves extending in the longitudinal direction on both sides, a rear wall, and both side walls hanging from both side edges of the rear wall, and the shield case. In a corona discharge device comprising a corona discharger main body having a discharge wire stretched in a shield case; At least one projecting piece is formed by projecting in the direction, and the corona discharger main body is detachably attached to the guide rail by inserting the projecting piece into the receiving groove of the guide rail. and an opening is created in each of the side walls or the rear wall by forming the protruding piece,
A corona discharge device characterized in that the inside and outside of the shield case are communicated through the opening. 2. The corona discharge device according to claim 1, wherein the projecting piece and the opening are formed by projecting a portion of each of the side walls laterally outward. 3. The corona discharge device according to claim 2, wherein a plurality of the projecting pieces and the openings are formed on each of the side walls of the shield case at intervals in the longitudinal direction. 4. The corona according to claim 2 or 3, wherein the protruding pieces formed on each of the side walls of the shield case are substantially flush with the rear wall of the shield case. Discharge device. 5. The corona discharge device according to any one of claims 1 to 4, wherein the protruding piece and the opening are longitudinally elongated rectangles. 6 The guide rail is provided with a spring member that elastically contacts the outer surface of the rear wall of the shield case and elastically holds the corona discharger main body at a predetermined position with respect to the guide rail. A corona discharge device according to any one of claims 1 to 5 of the utility model registration claims. 7. Furthermore, a protective cover is provided which is fixed between the part where the corona discharger main body is attached and the part where the member to be subjected to corona discharge is located, and the protective cover has the discharge wire of the corona discharger main body. 7. The corona discharge device according to any one of claims 1 to 6, wherein a discharge width regulating opening is formed to regulate the width of the corona discharge current from the corona discharge current to the member to which corona discharge is to be performed.