JPH0362066A - Image forming device - Google Patents

Abstract

PURPOSE:To surely fix a toner hopper in a state its connection to a developing device is released and to allow the hopper to completely adhere to the developing device in a state the toner hopper is connected to the developing device by providing a cam with an engaging groove engaged with a hopper shaft and with an engaging projection. CONSTITUTION:To remove the developing device 1 from the device main body, a laser shaft 5 is rotated counterclockwise, and then the hopper shaft 3 slides on the surface of the cam 4 to move. When the shaft 3 reaches a prescribed position, the hopper shaft 3 of the toner hopper 2 is surely engaged with the engaging groove 6 of the cam 4, whereby the toner hopper never removes from the cam 4 if vibration, etc., are given. To load the developing device 1 to the device main body, the lever shaft 5 reaches the prescribed position as it is rotated clockwise. At this time the hopper shaft 3 of the toner hopper 2 is pressed against the developing device 1 with the hopper shaft 3 of the toner hopper 2 surely engaged with the engaging projection 7 of the cam 4. Thus, the connection of the toner hopper 2 to the developing device 1 is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an image forming apparatus, and particularly to an image forming apparatus in which a toner hopper moves up and down with respect to the developing apparatus when the developing apparatus is installed and removed inside the main body of the image forming apparatus. The present invention relates to a forming device.

(Prior Art) Generally, in an image forming apparatus in which a developing device is detachably installed inside the main body of the image forming apparatus, a toner supply section that supplies toner from an upper toner hopper to a lower developing device is used to connect the developing device to the image forming apparatus. Some devices are designed to slide when attached to or removed from the main body.

However, according to this image forming apparatus, since the developing device is attached and detached by sliding, high positional accuracy is required, resulting in high cost, or the sliding part is installed to reduce the burden on the operator when attaching and detaching the developing device. If the size of the toner is made smaller, there are problems such as a complicated toner supply route.

Therefore, first, the present inventor proposed Utility Application No. 63-141421.
In this issue, we proposed an image forming apparatus shown in FIG. This image forming apparatus A includes a developing device 1, a toner hopper 2 disposed above the developing device 1, and a toner hopper 2.
The hopper shaft 3 has a hopper shaft 3 fixed to the hopper shaft 3, a cam body 4 that engages with the hopper shaft 3, and a lever shaft 5 to which the cam body 4 is attached and rotatably disposed inside the device main body. When the developing device 1 is slid in the axial direction of its developing roller to be attached to and removed from the main body of the image forming apparatus A, the lever shaft 5 is rotated to actuate the cam body 4 and the toner hopper 2 is moved into the developing device. It is designed to move up and down in the vertical direction with respect to the device l. The broken line in the figure shows the state in which the toner hopper 2 is raised relative to the developing device 1.

(Problems to be Solved by the Invention) However, according to the image forming apparatus A described above, when the toner hopper 2 is raised relative to the developing device 1 and is disconnected from the developing device 1, the developing device 1 There have been cases where the hopper shaft 3 is displaced from the cam body 4 due to vibrations generated when the toner hopper 2 is removed, causing the toner hopper 2 to descend.

Furthermore, when the toner hopper 2 is lowered relative to the developing device 1 and connected to the developing device 1, the toner hopper 2 and the developing device 1 are connected only by the weight of the toner hopper 2, so for example, the toner hopper 2 When the toner inside the toner hopper 2 is consumed and the weight of the toner hopper 2 decreases, the adhesion state decreases and the toner inside the toner hopper 2 decreases.
When the toner hopper is disconnected from the developing device, the toner hopper can be securely fixed, and when the toner hopper is connected to the developing device, the toner can be An object of the present invention is to provide an image forming apparatus in which a hopper and a developing device can be brought into close contact with each other.

(Means for Solving the Problems) The image forming apparatus of the present invention includes a developing device, a toner hopper disposed above the developing device, a hopper shaft fixed to the toner hopper, and a hopper shaft that is engaged with the hopper shaft. a lever shaft to which the cam body is attached and rotatably disposed inside the main body of the image forming apparatus, and the developing device is slid in the axial direction of the developing roller to be detached from the inside of the main body of the image forming apparatus. When doing,
In an image forming apparatus in which a cam body is actuated by rotating the lever shaft to raise and lower the toner hopper in a vertical direction with respect to a developing device, the cam body causes the toner hopper to move up and down with respect to the developing device and develop the toner hopper. An engagement groove that engages with the hopper shaft of the toner hopper when the connection with the device is released, and a state that engages the hopper shaft of the toner hopper when the toner hopper descends relative to the developing device and connects with the developing device. This is provided with an engaging protrusion for pressing against the developing device side.

(Function) According to the image forming apparatus of the present invention, when the toner hopper rises relative to the developing device and disconnects from the developing device, the hopper shaft of the toner hopper engages with the engagement groove of the cam body. When the toner hopper is lowered relative to the developing device and connected to the developing device, the hopper shaft of the toner hopper is pressed toward the developing device while being engaged with the engagement protrusion of the cam body.

(Example) Hereinafter, an example of the image forming apparatus of the present invention will be described based on FIG.

FIG. 1 is a cross-sectional view showing an embodiment of an image forming apparatus according to the present invention, and FIG. 2 is a cross-sectional view of essential parts of this embodiment.

In the following description, the same reference numerals are used for the same elements as those in the image forming apparatus A shown in FIG. 3, and the description thereof is omitted.

In this embodiment, the difference from the conventional image forming apparatus A is that, as shown in FIGS. 1 and engages with the hopper shaft 3 of the toner hopper 2 when the connection with the developing device 1 is released. This is because an engaging protrusion 7 is provided for pressing the developing device 1 in an engaged state with the hopper shaft 3 of the toner hopper 2 when the toner hopper 2 is connected.

Here, the engagement groove 6 is formed so that its cross section is approximately equal to the cross section near the outer periphery of the hopper shaft 3 so that it can engage with the hopper shaft 3 and securely hold the toner hopper 2. . On the other hand, the engagement protrusion 7 has an arc shape,
The semicircle formed between the inner surface of the engaging protrusion 7 and the surface of the cam body 4 facing the inner surface is approximately equal to the semicircle of the cross section of the hopper shaft 3. As a result, the hopper shaft 3 is pressed toward the developing device (2) in an engaged state.

The operation of this embodiment based on the above configuration will be explained.

When removing the developing device 1 from the main body of the device, by rotating the lever shaft 5 in the counterclockwise direction in the figure, the hopper shaft 3 is moved to the cam body 4 as shown by the solid line in FIGS.
When the hopper shaft 3 of the toner hopper 2 slides on the surface of the toner hopper 2 and reaches a predetermined position, the hopper shaft 3 of the toner hopper 2 reliably engages with the engagement groove 6 of the cam body 4. Therefore, the cam body 4 will not come off. When the developing device 1 is installed in the main body of the device, rotating the lever shaft 5 clockwise in the figure will cause the
As shown by the broken line in the figure, when the toner hopper 2 reaches a predetermined position, the hopper shaft 3 of the toner hopper 2 is firmly engaged with the engagement protrusion 7 of the cam body 4 and is pushed toward the developing device 1. As a result, the connection between the toner hopper 2 and the developing device 1 becomes better.

(Effects) According to the image forming apparatus of the present invention, the toner hopper can be reliably fixed when the toner hopper is disconnected from the developing device, and the toner hopper can be securely fixed when the toner hopper is connected to the developing device. The toner hopper and the developing device can be brought into close contact with each other completely.

[Brief explanation of drawings]

1 is a sectional view showing an embodiment of an image forming apparatus according to the present invention, and FIG. 2 is a sectional view showing a conventional image forming apparatus. A... Image forming device, 1... Developing device, 2... Toner hopper 3... Hopper shaft, 4... Cam body,
5...Lever shaft, 6...Engagement groove, 7...Engagement protrusion

Claims (1)

[Claims] (1) A developing device, a toner hopper disposed above the developing device, a hopper shaft fixed to the toner hopper, a cam body that engages with the hopper shaft, and the cam body attached and rotated inside the device main body. It has a lever shaft that can be freely arranged,
When the developing device is slid in the axial direction of the developing roller and removed from the inside of the image forming apparatus main body, the lever shaft is rotated to operate the cam body and move the toner hopper up and down with respect to the developing device. In the image forming apparatus that moves up and down in the direction, the cam body includes an engagement groove that engages with a hopper shaft of the toner hopper when the toner hopper rises relative to the developing device and disconnects from the developing device; An image forming apparatus characterized in that an engaging protrusion is provided for pressing the toner hopper toward the developing device while engaging the hopper shaft of the toner hopper when the toner hopper is lowered relative to the developing device and connected to the developing device.