JPH11133827A - Printing device - Google Patents

Abstract

(57) [Summary] In a conventional device, a reaction force of toner conveyance is concentrated on a fixed portion due to brazing, and a spiral member is detached or broken from a drive shaft. The present invention relates to a hollow pipe through which a developer collected from a photosensitive device passes through a developer collecting device, a spirally wound wire arranged in the hollow pipe and driven to rotate, The drive shaft is configured such that a pin with which the end of the wire is loosely engaged is erected and driven to rotate. According to the present invention, the life of the spiral member can be extended, the reliability of the printing apparatus can be improved, and the size of the printing apparatus can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus, and more particularly, to a developer recovery device for transporting a developer (hereinafter, referred to as toner) discharged from a photosensitive device.

[0002]

2. Description of the Related Art In a conventional developer collecting device, a spiral member for conveying toner discharged from a photosensitive device is fixed to a drive shaft by brazing or screwing with solder or the like.

[0003]

As a result, the reaction force of toner conveyance is concentrated on the fixing portion, and the spiral member is disengaged or broken from the drive shaft.

In addition, it is necessary to increase the size of the mounting portion for brazing, which restricts the arrangement of parts and hinders miniaturization of the device.

[0005]

SUMMARY OF THE INVENTION The present invention is characterized by an optical device for forming a latent image, a photosensitive device, a developing device for developing the latent image, and a recovery of excess developer generated after the development. In the printing apparatus provided with a developer recovery device that performs, the developer recovery device is a hollow pipe through which at least the developer recovered from the photosensitive device passes, and is disposed in the hollow pipe and is rotationally driven. The printing apparatus is characterized by comprising a spirally wound wire rod and a drive shaft that is rotatably driven by setting a pin into which the end of the wire rod is loosely engaged.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

The printing apparatus main body 25 includes developing devices 1 to 4,
Optical unit 5, charging unit 8, photosensitive belt 22, transfer drum 21, registration roller 12, transfer roller 13, static eliminator 15, fixing unit 19, paper discharge roller 18, and paper supply cassette 6.
Are the main components.

The operation of the printing device 25 will be described below.

The charger 8 uniformly charges the photosensitive belt 22 in response to a print start signal from a host (not shown).

The optical unit 5 draws a latent image on the photosensitive belt 22 according to the print data sent from the host, and the drawn latent image is developed by any one of the developing units 1 to 4. The colored particles in the developing device are applied on the photosensitive belt 22.

The photosensitive belt 22 is rotated by a driving source (not shown), and is placed on the transfer drum 21.
Transfer the colored particles above.

Excessive colored particles remaining on the transfer drum 21 are removed by the cleaner 20, and excessive colored particles remaining on the photosensitive belt 22 are removed by the cleaner 23, and the photosensitive belt 22 is again charged by the charger 8. Is charged by.

In the case of color printing, this process is repeated three or four times while switching the developing device.

A visible image is formed on the transfer drum 21 by colored particles of a single color or a plurality of colors, and the paper 27 is fed from the paper feed cassette a6 or the paper feed cassette b7 when the desired transfer is completed or in advance. Pulled out by the paper feed roller a10 or the paper feed roller b24, the registration roller 1
Wait at 2.

At a timing when the position of the visible image formed on the transfer drum 21 coincides with the transfer position on the sheet, the sheet waiting at the registration roller 12 starts to be conveyed again and the transfer roller At 13 the visible image is transferred to the paper side.

The paper is peeled off from the transfer drum 21 by the static eliminator 15, and the colored particles are fixed on the paper by the fixing device 19 and are discharged to the paper discharge tray 28.

Excess toner removed by the cleaner 20 and the cleaner 23 passes through a duct (not shown), is lifted upward from below a duct pipe 33 having a built-in conveying spiral member, and is placed in a waste toner bottle 32. Sent in.

FIG. 2 shows a moving path of the surplus toner. Excess toner from the transfer drum 21 is supplied to the blade a45.
It is scraped off and transported by the rotating transport spiral member a47 in the direction of the arrow shown in FIG.

Further, upon reaching the position of the duct 49,
At the same time as the surplus toner falls under its own weight, the conveying spiral member c vibrates up and down by a gear a52 driven by a driving source (not shown) to assist the surplus toner to drop and is conveyed in the direction of the arrow shown in FIG.

On the other hand, excess toner generated from the photosensitive belt 22 is scraped off by the blade b46, and is conveyed in the direction of the arrow shown in FIG. 2 by the rotating conveying spiral member b48.

The surplus toner passes through the joining port 56 and reaches a surplus toner merge point 57. At the surplus toner merge point 57, the gears d, c, and b driven by a driving source not shown here.
As a result, the rotational force is transmitted to the conveying spiral member d, and the surplus toner at the surplus toner merging point 57 is conveyed through the duct pipe 33, and the surplus toner is discharged from the outlet of the duct pipe 33.

As shown in FIG. 3, the transport spiral member d51 is
Gear b to which power from a drive source not shown is transmitted
It is attached so as to be entangled with a pin 83 erected on a drive shaft 84 to which 53 has been attached.

Here, the transport spiral member d51 is formed as a spirally wound wire (so-called coil).

FIG. 4 shows a state in which the pin 83 is viewed from the sectional direction.

Then, the drive shaft 8 is provided on the transport spiral member d51.
The rotational force is transmitted from the pin 83 of the fourth
A reaction force is generated in the transport spiral d51 due to the frictional force with the inner wall surface of the transport spiral and the transport of the surplus toner, and the reactive force is generated as shown in FIG. It is absorbed by the elasticity of the transport spiral d51 at the contact portion of the transport spiral d51.

When the conveying spiral d51 receives a force exceeding the conveying force in the duct pipe 33, the bending of the hook portion further proceeds, and the conveying spiral d51 passes through the gap between the pin 83 and the gear b53.
The hook portion 51 comes off and goes around the drive shaft 84 by half the circumference and is hooked again at the projecting portion of the pin 83 on the opposite side.

By repeating this process several times, the stress exceeding the abnormal conveying force due to the adhesion of the excess toner is gradually released, and the normal conveying state is restored.

[0028]

According to the present invention, the life of the spiral member can be extended, the reliability of the printing apparatus can be improved, and the size of the printing apparatus can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a printing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a conveyance path of surplus toner according to the embodiment of the present invention.

FIG. 3 is a detailed view of a mounting portion of a transport spiral showing one embodiment of the present invention.

FIG. 4 is a detailed view of a mounting portion of a transport spiral showing one embodiment of the present invention.

FIG. 5 is a detailed view of a mounting portion of a transport spiral showing one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Developing device 1, 2 ... Developing device 2, 3 ... Developing device 3, 4 ... Developing device 4, 5 ... Optical unit, 6 ... Paper cassette 1, 7 ... Paper cassette 2, 8 ... Charging device, 10 ... Paper feed rollers 1 and 12
... Registration roller, 13 ... Transfer roller, 15 ... Static eliminator,
Reference numeral 18 denotes a discharge roller, 19 denotes a fixing unit, 20, 23 a cleaner, 21 a transfer drum, 22 a photosensitive belt, 24 a paper feed roller 2, 25 a printing apparatus main body, 27 paper, and 28 a paper discharge tray. 29: paper detector, 30: printer controller, 32: toner bottle, 33: duct pipe, 39
... door, 45 ... blade a, 46 ... blade b, 47 ...
Conveyor spirals a, 48 ... Conveyor spirals b, 49 ... ducts, 50 ...
Conveyor spirals c, 51 ... Conveyor spirals d, 52 ... Gears a, 53 ...
Gear b, 54 ... gear c, 55 ... gear d, 56 ... joint,
57: surplus toner junction; 83: shaft; 84: drive shaft.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Toshihiro Abe 1-1-1, Higashitagacho, Hitachi City, Ibaraki Pref.

Claims (1)

[Claims] 1. A printing method comprising: an optical device for forming a latent image; a photosensitive device; a developing device for developing the latent image; and a developer collecting device for collecting excess developer generated after development. In the apparatus, the developer recovery device is a hollow pipe through which at least the developer recovered from the photosensitive device passes, and a helically wound wire that is disposed in the hollow pipe and driven to rotate, A printing device, comprising: a drive shaft that is rotatably driven by a pin in which an end of the wire is loosely engaged.