JPS62226164A - Image forming device - Google Patents

Abstract

PURPOSE:To obtain an image forming device equipped with a developing bias supply means having good operability by separating a voltage-supplied member from a bias voltage supply member through the opening operation of an upper unit and bringing them into contact through the closing operation of the upper unit. CONSTITUTION:A leaf spring member 85 has its upper end part 85a interposed in a guide groove 65a as the shaft guide part of one guide member 65 and when a developing device 9 is inserted, the member contacts the shaft 33c of a developing roller 33 and also presses the developing device 9 against one side to position the device in its front-rear direction. The tip part of the upper end part 85a of the leaf spring member 85 is curved outward to an obtuse angle and pressed against the end surface of the shaft 33c, so that a bias voltage is applied. The lower end part 85b projects downward from the lower end part of the guide member 65 and contacts a terminal 88 as a bias voltage supply member when an upper unit is put on a lower unit, thereby sliding the terminal 88.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an image forming apparatus such as an electronic copying machine or a laser printer, and particularly relates to an image forming apparatus that can be separated into an upper unit and a lower unit. The present invention relates to an improvement in an image forming apparatus having a developing bias supply means for applying a bias voltage generated from a bias voltage generation source incorporated in a lower unit to a developing device incorporated in an upper unit.

(Prior Art) In recent years, image forming apparatuses such as electronic copying machines have become more compact, and in these types of small models, the paper transport path is usually designed to facilitate removal of paper jams, maintenance and inspection, etc. It has a structure that allows it to be divided into upper and lower units almost at the border. Further, the image forming apparatus usually includes a developing bias supply means for applying a bias voltage to the developing device in order to prevent image fogging.

However, conventionally, a developing bias supply means for applying a bias voltage generated from a bias voltage generation source incorporated in a lower unit to a developing device incorporated in an upper unit has been connected to a harness using connectors of electrical appliances, or Alternatively, a dedicated connector is used for positioning and connection.

However, in the former case, the length of the harness must be equal to the distance between the upper and lower units, which not only requires a dedicated storage space, but also requires time and effort to separate and connect. Also,
In the latter case, it is easy to separate and connect by using a dedicated connect, but there are drawbacks such as being expensive and restricting placement.

(Problems to be Solved by the Invention) As described above, the conventional developing bias supply means between the upper unit and the lower unit has a complicated structure, is limited in space, and is troublesome to separate and connect. There were problems such as high cost and high cost.

The present invention has been made based on the above-mentioned circumstances, and aims to have a simple configuration, take up little space, and be inexpensive. It is an object of the present invention to provide an image forming apparatus equipped with a developing bias supply means with good workability, which can separate and connect electrical connection with a bias voltage generation source by opening and closing an upper unit.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides an upper unit and a lower unit that can be separated, and a developing device incorporated in the upper unit that has a lower unit. In an image forming apparatus having a developing bias supply means for applying a bias voltage generated from a bias voltage generation source built in a A bias voltage supply member is provided in the lower unit to face the member to which bias voltage is supplied and is connected to a bias voltage generation source, and the bias voltage is supplied to the member to be supplied with bias voltage by the opening operation of the upper unit. The bias voltage supply member is separated from the bias voltage supply member and is configured to be brought into contact with the bias voltage supply member by the closing operation of the upper unit.

(Function) That is, in the present invention, by opening and closing the upper unit, the bias voltage supplied member provided in the upper unit is brought into contact with and separated from the bias voltage supply member provided in the lower unit.

This eliminates the need for connectors, harnesses, etc. as in the past, making it simple, space-saving, low-cost, and
It can be easily separated and connected.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 2(a) is a schematic longitudinal sectional front view of the copying apparatus as an image forming apparatus, and the second section (b) is a perspective view showing the upper unit in an open state. And its configuration is as follows.

In the figure, reference numeral 1 denotes a copying apparatus main body as an image forming apparatus main body.A document table 2 is provided on the top surface of the copying device main body 1 so as to be able to freely move back and forth, and an operation panel is provided on the front edge of the top surface. ing.

Further, a paper feed cassette 3 is attached to the right side of the copying apparatus main body 1, and a cassette cover 4 of the paper feed cassette 3 serves as a manual paper feed table 5 for manually feeding paper P as appropriate.

A drum-shaped photoreceptor 6 is provided approximately at the center of the main body 1 of the copying apparatus, and a charging device 7 is provided around the drum-shaped photoreceptor 6. Exposure device 8. Developing device9. Transfer device 10, peeling device M11.
and cleaning device 12 are sequentially arranged.

Further, in the lower part of the copying apparatus main body 1, paper P1 supplied from an automatic paper feeder 15 equipped with a paper feed cassette 3 and paper P supplied from a manual paper feed tray 5 are transferred to the photoreceptor 6. A paper transport path 18 is formed which leads to a paper discharge tray 17 provided on the left side of the copying apparatus main body 1 via an image transfer section 16 between the copying apparatus 10 and the copying apparatus 10 .

Further, a pair of aligning rollers 20 is arranged on the upstream side of the image transfer section 16 of the paper transport path 18, and a fixing device 21 and a pair of paper discharge rollers 22 are arranged on the downstream side.

Further, the upper unit 25a and the lower unit 25b can be separated with the paper transport path 18 as a boundary, and if necessary, the upper unit 25a can be moved upward as shown in FIG. 2(b). The structure is such that removal of paper jams, maintenance and inspections, etc. can be easily performed.

During the copying operation, the photoreceptor 6 is driven by a drive mechanism (not shown) clockwise (in the direction of the arrow) in the state of FIG. The exposure lamp 23 of No. 8 is turned on. First, the charging device 7 uniformly charges the document image, and the exposure device 8 forms an image of the document set on the document table 2 on the photoreceptor 6, thereby forming an electrostatic latent image thereof. Then,
This electrostatic latent image on the photoreceptor 6 is sent to the transfer device 1o as a developer image by a developing device 9 that uses a two-component developer consisting of toner a and carrier b.

On the other hand, a paper P that is automatically or manually fed is fed through seven lining roller pairs 20, and the developer image previously formed on the photoreceptor 6 is transferred to the paper P by the action of the transfer device 10.
transcribed into. Then, the paper P is peeled off from the photoreceptor 6 by a peeling device 11 using AC corona discharge, passes through a conveyance path 18, and is sent to a fixing device. Here, after the developer image is fused and fixed on the paper P, it is discharged onto the paper discharge tray 17 by a pair of paper discharge rollers 22 .

Note that after the developer image is transferred onto the paper P, the residual toner remaining on the photoreceptor 6 is cleaned by the cleaning device 12, and the next copying operation is ready.

The developing device 9 has a structure as shown in detail in FIGS. 3 to 8.

That is, the developing device 9 includes a lower unit 30a and an upper unit 30b, and the lower unit 30a includes a developing mechanism section 31 and a developer stirring section 32.

The developing mechanism section 31 includes a developing roller 33 disposed opposite to an opening 41 in a lower casing 40a of a developing device main body 40, and a developer magnetic brush D' formed on the surface of the developing roller 33 exposed to light. A developer magnetic brush D' is provided at the sliding contact portion with the body 6, that is, on the upstream side of the development position 34.
The developer magnetic brush D' has a doctor 35 for regulating the thickness thereof, and a thin plate member 36 for leveling the developer magnetic brush D' whose thickness is regulated by the doctor 35. Further, the developer stirring section 32 includes first and second developer stirring bodies 38.3 accommodated in the developer storage section 37 in the upper casing 40b of the developing device main body 40.
9.

Further, the developing roller 33 is composed of a magnetic roll 33a having five magnetic pole parts, and a rotating sleeve 33b that is fitted onto the outside of the magnetic roll 33a and rotates counterclockwise in the figure.

The rotary sleeve 33b is in a so-called with mode in which it rotates counterclockwise in the figure to perform development, and slides the developer brush D' held on its surface in a direction that follows the flow of the image on the photoreceptor 6. By bringing them into contact with each other, sufficient development time is ensured, and the electrostatic latent image formed on the photoreceptor 6 is developed in a high-quality image state.

Further, the upper unit 30b is fixed to the lower unit 30a via a plurality of screws 54, so that the front side and the rear side are fixed and integrated, and the upper unit 30b is fixed to the lower unit 30a via a handle 60 attached to the upper unit 30b. It is now possible to lift it.

Further, the developing device 9 configured as described above is formed in the copying machine main body 1 through an opening 61 for inserting and removing the developing device formed on the upper surface side of the copying machine main body 1, as shown in FIG. The structure is such that it can be attached to and detached from the attached part. Note that in order to expose the opening 61, the upper cover 62 may be opened after sliding the document table 2.

The shaft 33c of the developing roller 33 protrudes from both ends of the developing device main body 40.
Both ends of 3C are guided and positioned by guide grooves 65a, 65a as shaft guide portions of guide members 65, 65 disposed on the front and rear sides of the mounted portion, as will be described later.

Further, on the front side of the lower unit 30a, a lever 66 for adjusting the main bridge position is provided, as shown in FIG. The configuration is such that the position of the magnetic pole portion facing the can be adjusted.

Further, the toner hopper 50 of the upper unit 30b is of a cartridge type, so that the toner hopper 50 can be replaced when the toner a runs out.

The hopper guide 67 that supports the toner hopper 50 is removable, and when the hopper guide 67 is removed, the developer concentration detector 51 is removed as shown in FIG.
．． The replenishing device driving means 53°, the control board 68, etc. are exposed.

The replenishment device driving means 53 transmits the driving force of the drive gear 70 to a driven gear 72 via a clutch 71, and drives the replenishment roller 52 including a gear (not shown) that meshes with the driven gear 72. Further, a drive signal to the clutch 71 is sent in response to a detection signal from the developer concentration detector 51.

Further, as shown in FIG. 8, the developing roller 33. is incorporated in the lower unit 30a. 1st. The second developer agitating bodies 38 and 39 are arranged to interlock with each other through a gear group 73 to 76 that mesh with each other in sequence, and the gear 74 is arranged to rotate together with the drive gear 70. There is.

The first developer agitating body 38 has blades 38a attached so as to be externally fitted obliquely to the rotating shaft 38b.
It is designed to move back and forth along the axial direction. The second developer stirring body 39 has blades 39b arranged in two rows at a phase of 180° along the axial direction of the rotating shaft 39a, and is located directly below the toner supply lower 7. The replenishing toner a is evenly mixed with the developer in the developer accommodating portion 37.

Next, the configuration of the guide member 65.degree. 65, which is disposed at the mounting portion to guide the developing device 9 constructed as described above, will be described with reference to FIGS. 1 and 9.

Each guide member 65,65 has a guide groove 658 as a shaft guide portion that directly guides both ends of the shaft 33c of the developing roller 33. This guide groove 6
5a is disposed asymmetrically with respect to the opening 61 for inserting and removing the developing device, so that when the developing device t9 is opposed to the opening 61, the end of the shaft 33c is aligned with the guide 116.
In addition, when the developing device 9 is turned in the opposite direction, the end of the shaft 33c comes into contact with the upper end side of the guide members 65 and 65, and further insertion is stabilized. A stopper portion 65b for preventing reverse insertion is formed.

As shown in FIG. 1, if the developing device 9 is inserted in the correct direction, it can be inserted into the mounting portion, and if the developing device 9 is inserted in the opposite direction, it cannot be inserted.

The guide members 65, 65 formed in this manner are made of a non-magnetic material, and are configured to smoothly guide the magnetized shaft 33C without being attracted to it.

Further, these guide members 65, 65 are fixed in a state in which positioning protrusions 81, 81 are fitted into positioning holes respectively formed in the main body frame. A hole is formed in the main body frame, into which a photoreceptor shaft for positioning the photoreceptor 6 is inserted and fixed, and the guide member 65, 65 is formed.
The developing device 9, which is attached to the attachment portion formed on the upper unit 25a through the above, is automatically positioned with respect to the photoreceptor 6, so that high positional accuracy can be obtained.

Further, to the developing device 9 incorporated in the upper unit 25a side, a bias voltage generated from a transformer 87 as a bias voltage generation source incorporated in the lower unit 25b is applied via a developing bias supply means 86, which will be described later. It is configured to do this.

That is, as shown in FIG. 11, the developing bias supply means 86 includes a leaf spring member 85 as a bias voltage supplied portion connected to the developing device 9 provided in the upper unit 25a, and a leaf spring member 85 facing the leaf spring member 85. It is preferably provided with a terminal 88 as a bias voltage supply section provided in the lower unit 25a and connected to the transformer 87.

As shown in FIGS. 1 and 10 to 13, the leaf spring member 85 has its upper end 85a interposed within the guide groove 5a serving as a shaft guide portion of one guide member 65. When the developing device 9 is inserted, it comes into contact with the shaft 33c of the developing roller 33 and its elasticity pushes the developing device W9 to one side to position it in the front-back direction. It has become.

The tip of the upper end 85a of this plate spring member 85 is bent outward at an obtuse angle, so that it does not interfere with the insertion of the shaft 33c, and moreover, the shaft 33c is reliably guided and its elasticity is The shaft 33c is sequentially positioned by force, and is securely brought into pressure contact with the end surface of the shaft 33c, so that a bias voltage is applied.

Furthermore, since the guide member 65 is made of an insulating material, no insulation treatment is required between it and the main body frame 82, and since it is surrounded by the guide groove 65a, it is safer than the conventional connector type.

The developing device 9, which has been inserted to a predetermined position using the guide members 65, 65 as a guide, is inevitably positioned downward by the guide groove 65a and in the front, back, left and right directions, but upward movement is limited to the handle 6o. This is done by folding down the handle 60 and locking the hook 86 integrally formed on the handle 60 with a locking pin (not shown) disposed on the mounting portion.

At this time, the portion of the hook 86 that contacts the locking bottle is wedge-shaped, and the developing device 9 is reliably pressed downward and does not float.

On the other hand, the lower end 85b of the leaf spring member 85 is connected to the guide member 6.
It protrudes downward from the lower end of the ring 5, and its tip is in contact with the inside at an acute angle.

When the upper unit 25a is superimposed on the lower unit 25b, that is, when the upper unit 25a is closed, the lower end portion is as shown in FIG. 12(a).

As shown in FIG. 1B, it comes into contact with the terminal 88 as a bias voltage supply member and slides on the terminal 88, and as shown in FIG. 1, it comes into a secure pressure contact state. A bias voltage generated from the transformer 87 is applied to the shaft 33G of the developing device 9 via the terminal 88 and the leaf spring member 85.

Further, the lower end 85b of the leaf spring member 85 is formed with a folded part 89 to prevent injury to hands and fingers, so that when the upper unit 25a is opened, even if the upper unit 25a is touched, there will be no injury. There is.

[Effects of the Invention] As explained above, the present invention can be separated into an upper unit and a lower unit, and a bias generated from a bias voltage generation source incorporated in the lower unit is applied to a viewing device incorporated in the upper unit. In an image forming apparatus having a developing bias supply means for applying a voltage, the developing bias supply means has a bias voltage supplied member connected to a developing device provided in an upper unit, and a bias voltage supplied member facing the bias voltage supplied member. A bias voltage supply member provided in the lower unit and connected to a bias voltage generation source is provided, and the opening operation of the upper unit separates the voltage supplied member from the bias voltage supply member, and the closing operation of the upper unit separates the voltage supplied member from the bias voltage supply member. The voltage supplied member is configured to be brought into contact with the bias voltage supply member. Therefore, the configuration is simple, does not take up much space, and is low cost. Furthermore, the electrical connection between the phenomenon device built into the upper unit and the bias voltage generation source built into the lower unit can be established by the opening/closing operation of the upper unit. It is possible to provide an image forming apparatus equipped with a developing bias supply means that can be separated and connected and has good workability.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic perspective view showing the configuration of a developing bias supply means to a developing device, and FIG. 2(a) is a schematic longitudinal sectional front view of the image forming device. , FIG. 2(b) is a perspective view showing the upper unit of the main body of the apparatus in an open state, FIG. 3 is a schematic front view of the developing device, and FIG. 4 is a schematic showing the front side of the developing device with the toner hopper removed. 5 is a schematic perspective view showing the rear side of the phenomenon device with the toner hopper removed. FIG. 6 is a schematic perspective view of the phenomenon device with the upper and lower units separated. FIG. 7 is a schematic perspective view showing the rear side of the phenomenon device with the toner hopper removed. is a perspective view of the upper unit with the hopper guide removed, FIG. 8 is an exploded perspective view showing the drive system of the lower unit, FIG. 9 is a schematic perspective view showing the state when the developing device is inserted and removed, and FIG. 10 is a perspective view of the upper unit. A front view of the guide member, FIG. 11 is an explanatory diagram showing the state of the main parts when the upper unit is closed, FIG. 12 is a perspective view showing the contact state of the leaf spring member to the terminal, and FIG. 13 is the developing device. It is an explanatory view showing a state at the time of insertion. 9...Developing device, 25a...Upper unit, 25b
...Lower unit, 33...Developing roller, 33a.
...Shaft, 85...Bias voltage supplied member (plate spring member), (&...Development bias voltage supply means, 8
7...Bias voltage generation source (transformer), 88...
Bias voltage supply members (terminals), 8 pieces...Folded parts to prevent scratches on hands and fingers. Applicant's representative Patent attorney Takeshi Suzue Foolish plan Figure 1 Figure 2 (b) Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 11 Figure 12 (a) (b ) (C) Figure 13

Claims (4)

[Claims] (1) Image formation that can be separated into an upper unit and a lower unit, and has a developing bias supply means that applies a bias voltage generated from a bias voltage generation source incorporated in the lower unit to a developing device incorporated in the upper unit. In the apparatus, the developing bias supply means includes a bias voltage supplied member connected to the developing device provided in the upper unit, and a bias voltage generating source provided in the lower unit opposite to the bias voltage supplied member. a bias voltage supply member, the voltage supplied member is separated from the bias voltage supply member by an opening operation of the upper unit;
An image forming apparatus characterized in that the voltage supplied member is brought into contact with a bias voltage supply member by a closing operation of the upper unit. (2) The image forming apparatus according to claim 1, wherein the member to which bias voltage is supplied is made of a plate spring member and is pressed into contact with the bias voltage supply member in an elastically deformed state. (3) The image forming apparatus according to claim 1, wherein a portion of the bias voltage supplied member directly contacts the shaft of the developing device. (4) Claim 2 or 3, characterized in that the leaf spring member has a folded part for preventing injury to hands and fingers.
The image forming apparatus described in .