JPS61203464A - Drum driving device - Google Patents

Abstract

PURPOSE:To reduce the size of a device by supporting cylindrical drum on plural rolls fitted rotatably on plural shafts which are provided fixed outside the drum and fixed to side plates in parallel to the center of the drum, and storing a motor inside the drum. CONSTITUTION:The plural shafts 4 parallel to the center shaft of the drum 1 are implanted in the side plates 5 and 12 outside of the cylindrical photosensitive drum 1. The respective shafts 4 have the rotatable rolls 2, which contact the outer periphery of the photosensitive drum 1. Further, the position of a collar 3 provided to each shaft 4 is determined in the lengthwise direction of the photosensitive drum 1. The motor 9 fitted to the side plate 12 with a stay 11 is put inside the photosensitive drum 1 and the torque of the motor 9 is transmitted to the photosensitive drum 1 through a gear box 10 and gears 7 and 6. Consequently, the device is reduced in size and the photosensitive drum 1 is heated with heat generated by the motor 9 to save electric power.

Description

[Detailed description of the invention] [Purpose of the invention] "Industrial application field" The present invention relates to an image forming apparatus such as an electrophotographic copying machine.

The present invention relates to improvements in the holding and transmitting mechanism for photosensitive drums used in digital copying machines and the like, and in particular to space saving of the drive transmitting mechanism and energy saving of the entire image forming apparatus.

``Prior Art'' Conventionally, this type of photoreceptor is provided in layers on the outer surface of a cylinder to form a photoreceptor drum, flanges are formed at both ends of the cylinder, the center of the flange is the center of rotation, and a drive transmission mechanism is installed on one side of the flange. It was common to configure and drive a In this case, the inside of the photoreceptor is a space.

Further, in the case of a photoconductor that requires temperature increase, such as an amorphous silicon photoconductor, there are cases in which a temperature-increasing member such as a heater is specifically constructed within the photoconductor drum in order to increase the temperature by more than 40 degrees Celsius.

``Problems to be Solved by the Invention'' In line with this, the diameter of photoreceptor drums has been reduced in line with the recent trend of downsizing of image forming apparatuses.
Furthermore, as the width of the image forming apparatus in the front and back direction in the same direction as the axial direction of the photoreceptor drum becomes smaller, the arrangement of the drive source and power transmission means, and the heat generation from the drive source and power transmission member in the image forming apparatus as a whole become smaller. It has become necessary to review the processing of However, if a flange is provided at the end of the photoreceptor drum and the drive is performed there, the power transmission member of the drive device is arranged in the axial direction of the photoreceptor drum, so that the front and rear of the image forming apparatus is This is also the reason why the width in the direction increases. Further, a separate space is required within the image forming apparatus for installing an electric motor for driving the photoreceptor drum, but it is difficult to reduce the installation space in consideration of heat radiation and the like.

Furthermore, if a heater is installed in the photosensitive drum, not only that member is required, but also extra electric power is required.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems in an image forming apparatus using a photosensitive drum, increase the possibility of downsizing the image forming apparatus, and reduce power consumption.

In a cylindrical image carrier drum whose outer periphery is in contact with a plurality of rollers that are rotatably supported by a shaft fixed to a frame, the drive motor of the image carrier drum is fixed to the frame and the drive motor of the image carrier drum is fixed to the frame. This is an image carrier drum drive device that is housed in an image carrier drum and has a power transmission means between the drive motor and the mW body drum.

``Operation'' (1ff) When the driving motor of the one-piece drum is energized, the image depositing drum is driven via the power transmission means.

The heat generated by the prime mover is transferred to the image carrier drum.

Keep your body warm.

"Embodiments" Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view, and FIG. 2 is a side view of FIG. 1, but is a projected view with the side plate indicated by the symbol /- in FIG. 1 removed.

On the side plates, axles are fixed to each side plate, spaced equally on the circumference, and rollers 2 are rotatably supported on the axles. In this implementation, the roller λ has its center at the apex position of the equilateral triangle. The roller has a collar J, and the collar 3 clamps the end face of the photoreceptor drum l to determine the axial position of the photoreceptor drum. The outer periphery of the roller is in contact with the outer periphery of the photoreceptor drum l. The photoreceptor drum is a cylindrical cylinder, and a photoconductive photoreceptor is provided in layers around the outer periphery except for both ends, and an electrophotographic device (not shown) is arranged around it.

The photoreceptor drum 1 may be provided with outer flanges at both ends and similarly supported at λ.

A drive motor 9 for the photosensitive drum l is accommodated within the cylinder of the photosensitive drum l. This prime mover? The output shaft end of is connected to the output shaft l of the gear pock i10 via a gear box IO fixed to the electric motor D. A pinion 7 fixed to the output shaft t meshes with an internal gear 6 press-fitted onto the inner periphery of the end of the photosensitive drum l. The reduction ratio of the gear box 10 is selected so that the photoreceptor drum 1 can rotate at an appropriate rotational speed.

The gear box 10 faces a side plate 12 with a stay 11 in between, and a small screw /J is inserted into the gear box IO through the side plate 1 and the stay, and is positioned and fixed. Wiring for the electric machine is tied, for example, to the stay l/ with a binding wire (not shown) and wired to the power source through the wiring hole 16 in the side plate l. /7. Ig is a temperature increase adjustment hole drilled in the side plate 12 at the position of each photoconductor drum, but depending on the type and size of the photoconductor material and electric motor, the temperature required to maintain the photoconductor at the required temperature may be changed. In some cases, the hole is a temperature increase adjustment hole/7. Only use one of the two, and do not open it further. Further, if the amount of heat generated by the electric motor is insufficient, residual heat may be introduced from, for example, a halogen lighting unit, a fixing device, or the like.

When power is supplied through the wiring 13, the electric motor is energized, its rotational force drives the output shaft 5 through the gear box 10, the small gear 7 rotates and the internal gear 6 is rotated, and the photoreceptor drum l is rotated. Rotate the roller, roll and rotate on the roller. The heat generated by the electric motor 9 heats the photoreceptor drum and raises the temperature of the photoreceptor. The temperature of this photoreceptor is for temperature increase adjustment, hole/7
．． /g.

Although the embodiment has been described using an image information carrier as a photosensitive drum, all drums carrying information such as magnetic drums and insulating drums are included in the present invention.

〔Effect of the invention〕

In the present invention, the prime mover is built in the image carrier drum, the prime mover is supported by the side plate that forms the frame of the device, and a power transmission means is provided between the prime mover and the image carrier drum, so that the power transmission of the image carrier drum is carried out outside the frame. The means are not outstanding. The image forming apparatus can be made smaller because there is no need to provide a space for a motor for rotating the image carrier drum elsewhere in the image forming apparatus. There is no need to provide a heater in the image carrier drum I, and the heater, power supply device and electric power to be supplied to the heater can be saved.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view of an embodiment of the present invention, and FIG.
FIG. l...Photosensitive drum!・・Side plate 6・・Internal gear 7・
- Small gear... Output shaft?・・Electric motor IO−・Gear box //−・Stay/Ko・・Side plate /! ··wiring. Figure 2

Claims (1)

[Claims] 1. In a cylindrical drum whose outer periphery is supported by a plurality of rollers arranged on the circumference and rotatably supported by a shaft parallel to the center of the circumference and fixed to the frame, the drive motor of the drum is fixed to the frame and housed in the drum, and a power transmission means is provided between the drive motor and the drum.