JPH09190083A - Connecting structure of contact part for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a failure in contacting and the generation of an electric wave noise by providing a receiving screw having a conical hollow in a receptacle and a spherical terminal in the power feeding spring of a transfer-separation charger. SOLUTION: The receiving screw 10 used as both of a fixing screw and receiving part for a plate terminal 3 is arranged in a frame 1a on the side of the receptacle 1 connected to an AC power source and the spherical terminal 12 attached to the top end of the power feeding spring 11 extended from the projecting part 6 of the transfer-separation charger 5 is connected to the tapered inwall of the conical receiving recess 10a of the receiving screw 10. Therefore, in the process of installing the transfer-separation charger 5 in an equipment, even if the positional relation between the spherical terminal 12 and the receiving screw 10 is deviated more or less, the terminal 12 is slid on a tapered surface in the recess 10a of the receiving screw 10, to be always and surely seated on the vertex of the bottom surface of the recess 10a, so that an electrical stable connection state is obtained. Since this connection state is never deviated by vibration, etc., as well, a very low discharge can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
The present invention relates to an image forming apparatus using an electrophotographic process such as a facsimile machine, and more particularly, to an improvement in a structure for detachably connecting a terminal of a separation charger to a receptacle on a device side.

[0002]

2. Description of the Related Art In an image forming apparatus using an electrophotographic process such as a copying machine, a printer and a facsimile machine, reflected light of an original or the like on a photoconductor uniformly charged by a charging means such as a charger. To form an electrostatic latent image, and a toner image obtained by adhering toner from the developing device to the electrostatic latent image is transferred and fixed on a transfer paper to form an image. The transfer of the toner image is performed by transferring the toner image on the transfer paper by applying a charge having a polarity opposite to that of the toner to the toner image on the photoconductor via the transfer paper by a transfer device such as a transfer charger. is there. At the position immediately downstream of the transfer means, there is a separation charger that performs corona discharge to reduce the electrostatic attraction force between the transfer paper and the photoconductor when the transfer paper is attracted to the photoconductor during transfer, and to separate the transfer paper and the photoconductor. To be done.

[0003]

SUMMARY OF THE INVENTION A transfer / separation charger in which a transfer charger and a separation charger are integrated has a terminal to be attached / detached to / from a receptacle on the device side. When a jam occurs between the gap and the like, the jam processing is performed after the terminals of the transfer / separation charger are removed from the receptacle. FIGS. 7 (a) and 7 (b) are views showing the connection structure between the terminals of the conventional transfer / separation charger and the receptacle, and a plate is provided on the inner bottom surface of the recess 2 of the receptacle 1 provided on the image forming apparatus main body side. The terminal 3 is fixed by a screw 4 or is insert-molded, and a power supply spring 7 extends from a projection 6 on the transfer / separation charger end block 5 side fitted in the recess 2. By setting the protrusion 6 in the recess 2 at the time of connection, the feeding spring 7 is elastically pressed against the plate terminal 3. However, in such a conventional connection structure, since the linear power supply spring 7 of the transfer / separation charger and the plate terminal 3 in the receptacle 1 are in contact with each other, the contact state becomes unstable, resulting in poor contact. Micro-discharge is likely to occur in the receptacle ((b)). Therefore, there is a problem that radio wave noise is generated due to this. Since this radio noise causes troubles such as malfunctions of devices located around the image forming apparatus, there has been a demand for improvement. The present invention has been made in view of the above, and a contact failure occurs due to the use of a coil spring as an electrical connection means between the terminal in the receptacle on the device body side and the transfer / separation charger side. Another object of the present invention is to provide a connection structure for contact portions of an image forming apparatus, which can prevent generation of radio noise caused by the above.

[0004]

In order to achieve the above object, the invention of claim 1 is a separation charger for separating the transfer paper, which has received the transfer of the image information on the photoconductor, from the photoconductor, and the separation charger. Has a receptacle that is detachably connected to the contact of and supplies power to the separation charger,
The contact on the side of the separation charger is a power supply spring, and in the image forming apparatus for making electrical connection by pressing the tip of the power supply spring to the contact on the receptacle side, the contact on the receptacle side has a conical concave shape on the tip surface. And a terminal plate fixed to the receptacle by the receiving screw. The contact on the side of the separation charger is the power feeding spring and the cone of the receiving screw fixed to the tip of the power feeding spring. And a spherical terminal which is fitted and seated in the concave portion. As described above, according to the first aspect of the present invention, the receptacle and the transfer / separation charger are provided by providing the receptacle screw having the conical recess and the spherical terminal on the power supply spring of the transfer / separation charger. It is possible to prevent the minute discharge and the radio noise by making the contact state of Stable and reliable and making the contact position constant.

The invention according to claim 2 is characterized in that the surface property of the inner surface of the recess of the receiving screw and the surface property of the spherical terminal pressed against the inner surface of the recess are 1.6a or less. If the surface roughness of the contact part of the device side receptacle and transfer / separation charger is rough, the contact area between the receptacle screw of the receptacle and the spherical terminal of the transfer / separation charger will be reduced, resulting in poor contact. Wake up. In addition, when the surface properties of both are rough, the slippage of the spherical terminal becomes poor at the time of contact, resulting in poor contact. According to the second aspect of the present invention, by defining the surface properties of the receiving portion of the receiving screw of the receptacle and the spherical terminal of the transfer / separation charger, the receptacle and the transfer
The connection state with the separation charger can be made more reliable and contact failure can be prevented.

According to a third aspect of the present invention, the electrical resistance of the receiving screw and the spherical terminal is set to 10 μΩcm. In the invention of claim 1, when the electric resistance between the receptacle screw of the receptacle and the spherical terminal of the transfer / separation charger is high, the conductivity is deteriorated, or the electric charges are accumulated in the receptacle screw and the spherical terminal, respectively. The problem of micro discharge occurs. According to the third aspect of the present invention, by defining the electric resistance of the receiving screw and the spherical terminal, the receptacle and the transfer / separation charger can be surely brought into conduction, and minute discharge can be prevented.

According to a fourth aspect of the present invention, the pressing force by which the power supply spring presses the spherical terminal into the recess of the receiving screw is set to 3000 nN or more. In the invention of claim 1, when the pressure applied from the transfer / separation charger to the receptacle receiving screw of the spherical terminal is weak, mechanical contact during paper feeding causes a contact failure between the spherical terminal and the receiving screw, resulting in minute discharge. Occurs, and radio noise occurs. According to the invention of claim 4, by defining the pressing force of the spherical terminal, contact failure can be prevented and minute discharge can be prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments shown in the drawings. FIG. 1 is a configuration diagram of a spherical terminal that constitutes the connection structure of the present invention, FIGS. 2 (a) and 2 (b) are side views and front views of a receiving screw, and FIGS. 3 (a) and 3 (b) are overall configuration of the connection structure. It is a figure and operation explanatory view. The same parts as those in FIG. 7 are designated by the same reference numerals. According to the connection structure of the present invention, a receiving screw 10 that serves as a fixing screw for the plate terminal 3 and a receiving portion is arranged on the frame 1a on the receptacle 1 side connected to an AC power source (not shown) on the device body side, and transfer / separation is performed. The characteristic point is that the spherical terminal 12 attached to the tip of the power supply spring 11 extending from the protrusion 6 of the charger 5 is connected to the tapered inner wall of the receiving recess 10a of the receiving screw 10. That is, the contact on the side of the receptacle 1 has a plate terminal 3 and a receiving screw 10 for fixing this to the frame 1a, and the contact on the side of the transfer / separation charger is composed of a palace spring 11 as a coil spring and a spherical terminal 12. Become. As shown in FIG. 1, the spherical terminal 12 has a hemispherical tip portion (contact portion) 12a and a small-diameter cylindrical power supply spring press-fitting portion 12b.
As shown in FIG. 1, a tip portion (contact portion) 12a that comes into contact with the receiving screw 10 has a hemispherical shape, and the contact portion 12a is a conical receiving recess of the receiving screw 10. The size is such that it easily enters the inside of 10a and comes into close contact with the inner wall thereof. Power supply spring press-fitting part 12b
Is 0.1 mm larger than the inner diameter of the tip of the power supply spring 11.
Both of them can be fixed by press-fitting the power feeding spring press-fitting portion 12b into the tip of the power feeding spring. In addition, the power supply spring press-fitting portion 12b
Has a smaller diameter than the contact portion 12a, the spring 1
The tip of 1 is locked at the stepped portion of the contact portion 12a.

The receiving screw 10 on the side of the receptacle 1 is shown in FIG.
As shown in FIG. 3, a screw portion 15 screwed into a screw hole of the plate terminal 3 and the receptacle 1, a cylindrical receiving portion main body 16 having a central portion fixed to one end of the screw portion 15, and a front surface of the receiving portion main body 16. It has a conical receiving recess 10a formed on the front side and a slotted part 17 formed on the front peripheral edge. Receiving recess 10
When the spherical terminal 12 is received, a is configured to be received at one place and to stabilize the electrical connection state. Specifically, the connection is stabilized by setting the angle of the bottom of the receiving recess 10a to 90 degrees. Ideally, as shown in FIG. 3 (b), a connected state in which the axis of the spherical terminal 12 and the axis of the receiving recess 10a coincide with each other is preferable.

Next, referring to FIGS. 3 (a) and 3 (b), an overall view of the connection structure of the present invention and the operation thereof will be described. The transfer / separation charger of the device 1 is inserted into the recess 2 of the receptacle 1 on the device side. The transfer / separation charger 5 is mounted by inserting the transfer / separation charger 5 into a predetermined position of the image forming unit so that the protrusion 6 is inserted, but the tip of the power supply spring 11 is crossed due to crossing of parts, positional displacement over time, and the like. The axis of the spherical terminal 12 may not match the axis of the receiving recess 10a (state of FIG. 3 (a)). That is, in the process of mounting the transfer / separation charger 5 on the device, the spherical terminal 12 slides on the tapered surface in the recess 10a of the receiving screw even if the positional relationship between the spherical terminal and the receiving screw is slightly deviated. Always recess 10
Since the seat can be reliably seated on the apex of the bottom surface of a, the connection state is electrically stable, the connection state is not shaken even by vibrations, etc., and minute discharge is eliminated. in this way,
The elastic deformation of the spring 11 and the spherical terminal 12 make the recess 10
By sliding in a, both can always be kept in a predetermined ideal positional relationship, and a stable connection state can be obtained.

Next, FIG. 4 is a diagram showing the relationship between the radio noise and the surface roughness of the contact surface of each of the spherical terminal and the receiving screw in the connection structure of the above-described embodiment. When the surface roughness values are 0.8a and 1.6a, the radio noise is stable and is 20 db or less, but when the surface roughness exceeds 1.6a, the radio noise value is Rose. As described above, in the present invention, by setting the surface roughness of the spherical terminal and the recess of the receiving screw to 1.6a or less, it is possible to sufficiently prevent the generation of radio noise due to the minute discharge. I understand.

Next, FIG. 5 is a diagram showing the relationship between the radio noise and the electrical resistance of the spherical terminal and the receiving screw in the connection structure of the above embodiment. In this example, the spherical terminal and the receiving screw are made of brass. Along with this, a case where gold plating or nickel plating is applied for corrosion prevention is shown. As is clear from this table, when the electric resistance is 10 μΩ · cm or less, the radio noise is stable and is 20 db or less, but when the electric resistance exceeds 10 μΩ · cm, poor conduction occurs and the radio noise is reduced. Rises. That is, the electric resistance is 10
When it is set to μΩ · cm, it is possible to reduce radio noise caused by minute discharge.

Next, FIG. 6 is a diagram showing the relationship between the radio noise in the connection structure of the above embodiment and the pressing force of the spherical terminal against the receiving screw. When the pressing force is less than 3000 mN, the pressing force is Insufficient state causes poor contact due to mechanical vibration, resulting in radio noise, but 3000
At mN and above, radio noise caused by minute discharge is 20db
I was able to keep it below. It should be noted that the appropriate values for the surface properties shown in FIG. 4, the appropriate values for the electrical resistance shown in FIG. 5, and the example of the appropriate values for the pressing force shown in FIG. 6 can be applied in combination with each other. . Therefore, by combining the form examples of FIGS. 4 and 5, the form examples of FIGS. 4 and 6, the form examples of FIGS. 5 and 6, and the form examples of FIGS. It is possible to realize the exhibited form example.

In the above embodiment, the transfer / separation charger in which the transfer charger and the separation charger are integrated is illustrated as an application target of the present invention. However, this is only an example, and the present invention uses a corona charger as a device. It is generally applicable when it is detachably connected to the main body. For example, the present invention can be applied to a connection structure in the case of a transfer charger alone and a separation charger alone. In the case of a separation charger, when a jam occurs with the photoconductor, it is necessary to remove the separation charger to perform jam processing, so it is necessary to facilitate the attachment / detachment work. In that case, not only is it extremely easy to remove, but also mechanical and electrical connection can be reliably achieved with one touch without any special and complicated adjustment work at the time of attachment. In the claims, the separation charger also includes a transfer charger or a separation charger integrated with the transfer charger.

[0015]

As described above, according to the first aspect of the invention, the receptacle screw having the conical recess is provided in the receptacle, and the feeding spring of the transfer / separation charger is provided with the spherical terminal. The contact state with the transfer / separation charger can be made stable and reliable, and the contact position can be made constant to prevent minute discharge and radio noise. According to the invention of claim 2, the surface property of the inner surface of the recess of the receiving screw,
The surface property of the spherical terminal pressed against the inner surface of the recess is 1.6.
Since it is set to a or less, by defining the surface properties of the receiving screw of the receptacle and the spherical terminal of the transfer / separation charger, the connection between the receptacle and the transfer / separation charger is made more reliable and contact failure is prevented. can do. In other words, in the conventional example, when the surface roughness of the contact part of the device-side receptacle and the transfer / separation charger is rough, the receiving part of the receptacle screw of the receptacle and the spherical terminal of the transfer / separation charger are connected. The contact area is reduced, resulting in poor contact. If the surface properties of both are rough,
Although the slippage of the spherical terminal is deteriorated at the time of contact to cause poor contact, the present invention can eliminate such a drawback of the conventional example. Although the number of parts of the spherical terminal increases, such an increase in the number of parts provides a certain merit by compensating for the problems caused by poor contact.

According to the third aspect of the present invention, since the electric resistivity of the receiving screw and the spherical terminal is set to 10 μΩcm, the receptacle and the transfer / separation charger are defined by defining the electric resistances of the receiving screw and the spherical terminal. It is possible to surely conduct electricity and prevent minute discharge. That is, in the conventional example, when the electrical resistance between the receptacle screw of the receptacle and the spherical terminal of the transfer / separation charger is high,
Although the conductivity is deteriorated, and electric charges are accumulated in the receiving screw and the spherical terminal, respectively, which causes a problem that a minute discharge occurs, but the present invention can solve such a problem. According to the invention of claim 4, since the pressing force of the power supply spring for pressing the spherical terminal into the recess of the receiving screw is 3000 nN or more, contact failure is prevented by defining the pressing force of the spherical terminal. It is possible to prevent minute discharge. That is, in the conventional example, when the pressure applied from the transfer / separation charger to the receptacle receiving screw of the spherical terminal is weak, mechanical contact during paper feeding causes a contact failure between the spherical terminal and the receiving screw, causing a small discharge, Although radio noise has occurred, the present invention can solve such a problem.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a spherical terminal that constitutes a connection structure of the present invention.

2A and 2B are a side view and a front view of a receiving screw.

3A and 3B are an overall configuration diagram and an operation explanatory diagram of a connection structure.

FIG. 4 is a diagram showing a relationship between radio noise and surface roughness of each contact surface of a spherical terminal and a receiving screw in the connection structure of the above-described embodiment.

FIG. 5 is a diagram showing a relationship between radio noise and electric resistances of a spherical terminal and a receiving screw in the connection structure of the above-described embodiment.

FIG. 6 shows radio noise in the connection structure of the above embodiment,
The figure which shows the relationship with the pressing force of a spherical terminal with respect to a receiving screw.

7A and 7B are explanatory diagrams of a conventional example.

[Explanation of symbols]

1 receptacle, 1a frame, 3 plate terminals, 5
Transfer / separation charger, 6 protrusions, 10 receiving screws, 1
0a recess, 11 power supply spring, 12 spherical terminal,
12a tip part (contact part), 12b power supply spring press-fitting part, 15 screw part, 16 receiving part body, 17 slitting part,

Claims (4)

[Claims] 1. A separation charger for separating the transfer paper, which has received the transfer of the image information on the photosensitive member, from the photosensitive member, and a receptacle which is detachably connected to the contact of the separation charger and supplies power to the separation charger. In the image forming apparatus, in which the contact on the side of the separation charger is a power supply spring and the tip of the power supply spring is pressed into contact with the contact on the receptacle side for electrical connection. The receiving screw having a conical recess, and the terminal plate fixed to the receptacle by the receiving screw, the contact on the side of the separation charger is the power supply spring,
A connection structure of a contact portion of an image forming apparatus, comprising: a spherical terminal fixed to a tip portion of the power supply spring and fitted and seated in a conical recess of the receiving screw. 2. The surface property of the inner surface of the recess of the receiving screw and the surface property of the spherical terminal pressed against the inner surface of the recess are 1.6a.
The connection structure of the contact portion of the image forming apparatus according to claim 1, wherein: 3. The electrical resistivity of the receiving screw and the spherical terminal is 10 μΩcm.
Alternatively, the connection structure of the contact portion of the image forming apparatus according to item 2. 4. The contact portion of the image forming apparatus according to claim 1, wherein the feeding spring presses the spherical terminal into the recess of the receiving screw with a pressing force of 3000 nN or more. Connection structure.