JPH09258558A - Image forming device - Google Patents

Abstract

(57) [Abstract] (Corrected) [PROBLEMS] Image forming apparatus capable of easily mounting a developing machine at a predetermined position with a simple structure and securely and easily engaging an input joint and a developing joint. To provide a developing machine driving device. SOLUTION: An engagement projection 13 is formed by a circumferential tapered surface 11 inclined in the axial direction and a flat surface 12 extending in the radial direction from the axis and passing through the axis, and a tapered surface of an engaging portion of an input joint 7. 11 and the tapered surface of the engaging portion of the developing joint are engaged with each other when the developing device is mounted on the main body, the shaft of the input joint and the drive source 1 for driving the shaft of the input joint are not interlocked. When the shaft and the driving source 1 are interlocked, the flat surface 12 of the engaging portion of the input joint and the flat surface of the engaging portion of the developing joint are engaged with each other, and the driving force of the driving source 1 is applied to the developing machine. Interlock with the drive axis of.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using electrophotography, and more particularly to a driving device for a developing machine thereof.

[0002]

2. Description of the Related Art In a developing machine of an image forming apparatus utilizing electrophotography, such as an electrophotographic copying machine, a laser printer, a facsimile, etc., a main roller of the image forming apparatus drives a developing roller and other rotating members to rotate to expose the photosensitive material. The latent image formed on the body is developed, but the developing machine needs to be attached and detached for maintenance and replacement. Therefore, it has been conventionally practiced to provide a joint that can be engaged and disengaged with a transmission system from the main motor to the drive shaft of the developing machine.

For example, in Japanese Utility Model Laid-Open No. 59-79865, a meshing of a drive gear driven by a main motor through a transmission means and a gear directly connected to a developing device drive shaft,
In order to facilitate the detachment, there is disclosed a contacting / separating device in which the developing machine can swing within a certain range around the axis of the drive gear. The mechanism for swinging in the plane became complicated and the operability was not good.

Therefore, as shown in FIGS. 4 and 5, on the end face of the sprocket or gear 3 which is rotationally driven by the motor 1 via the transmission means (gear 2 in this example), the sprocket is passed through the center and radially on both sides Pins 6 provided on both sides in the radial direction of the intermediate shaft 5 are engaged with the grooves 4 provided in one character, and an input joint 7 provided at one end of the intermediate shaft 5 is provided at the end of the drive shaft 9 of the developing machine 8. The developing machine is driven by engaging with the detachable developing joint 10, and the developing machine is axially pulled out from the main body of the apparatus by detaching the joints 7 and 10. There is known a developing device driving device which can be used.

As shown, the joints 7 and 10 have a plurality of engaging projections 13 formed by a tapered surface 11 inclined in the same direction in the circumferential direction and a part 12 of a flat surface extending in the radial direction from the axis. Is provided on the circumference of one surface of the joint disc, and the input joint 7 is also the developing joint 1.
0 has the same shape.

In the conventional device, as shown in detail in FIG. 5, the groove 14 provided in the gear 3 has a margin for smoothly inserting the pin 6 erected on the intermediate shaft 5, There is not enough room for the intermediate shaft 5 to rotate with respect to the gear 3 more than that. Therefore, when the developing machine 8 is moved in the axial direction as shown by the arrow in FIG. 4 and mounted on the apparatus main body, when the projection 13 of the developing joint 10 comes into contact with the tapered projection 13 of the input joint 7, Unless the shaft of the main motor 1 rotates or the input shaft 9 of the developing machine 8 does not rotate, the input shafts on the developing machine side advance axially due to the sliding of the taper portions, and the joints engage accurately. However, the developing machine is not mounted at the predetermined position. However, the main motor shaft is locked when stopped, and since the developer also contains developer, the torque required to rotate the shaft is large,
Since the shaft does not rotate simply by pushing in the developing machine, it is difficult to mount the developing machine.

[0007]

SUMMARY OF THE INVENTION The present invention eliminates the above-mentioned drawbacks of the conventional developing device driving device having the above-described structure, and easily mounts the developing device at a predetermined position with a simple structure, and the input joint and the developing device. An object of the present invention is to provide a developing device drive device that can be reliably and easily engaged with a joint.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides an input joint having an engaging projection provided at one end of a shaft, and an engaging portion having the same shape as the engaging projection of the input joint. An image forming apparatus having a developing joint provided at the drive shaft end of the developing machine, and mounting the developing device on the main body so that the input joint and the developing joint engage and rotate on the same axis. The engagement projection is formed by a circumferential tapered surface inclined in the axial direction and a flat surface extending in the radial direction from the axis and passing through the axis, and the engagement surface between the tapered surface of the engaging portion of the input joint and the developing joint is When the tapered surface of the joint portion is engaged with the developing device on the main body, the shaft of the input joint and the drive source for driving the shaft of the input joint are not linked and the shaft of the input joint is When When a drive source for driving the axes of the entry forces the joint is interlocked, the plane of the engaging portion of the developing joint the plane of the engagement portion of the input joint engages,
The driving force of the driving source is interlocked with the driving shaft of the developing machine.

[0009]

[Operations and Effects] The engaging projections of the input joint and the developing joint are formed by a circumferential taper surface inclined in the axial direction and a plane extending in the radial direction from the axis and passing through the axis. When the tapered surface of the joint portion and the tapered surface of the engaging portion of the developing joint engage with each other when the developing device is mounted on the main body, a shaft of the input joint and a drive source for driving the shaft of the input joint are connected. Since it is not linked, it is not necessary to manually move the joint to mount it at a predetermined position, which is easy. Further, the developing device can be securely mounted at a predetermined position without being driven in a state of being displaced in the axial direction, and the developing roller of the developing device and the latent image area of the photoconductor in the axial direction surely coincide with each other so that the end portion of the image is chipped It is possible to prevent the toner from adhering to the edges.

Further, the engaging projection is formed by a circumferential taper surface which is inclined in the axial direction and a plane which extends in the radial direction from the axis and passes through the axis, and the axis of the input joint and the axis of the input joint are separated from each other. When the driving source to be driven is interlocked, the flat surface of the engaging portion of the input joint and the flat surface of the engaging portion of the developing joint are engaged, and the driving force of the driving source is interlocked with the driving shaft of the developing machine. When driving, there is no possibility that the respective shafts will be shaken in the axial direction, and the developing roller of the developing device and the latent image region of the photoconductor in the axial direction can be surely aligned with each other to prevent chipping of the end of the image and adhesion of the end of the toner. Further, it is possible to prevent the rotational torque from increasing due to unnecessary contact between the bearing and the like that receive the shaft and the respective joints and the like.

Further, even if the axis of the input joint and the axis of the developing joint are not completely coincident with each other, and even if the axes are deviated from each other, the respective planes can be brought into sliding contact with each other to rotate the joint.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is shown in FIG. 5 in which the developing device side drive shaft and the joint attached thereto are omitted in the embodiment in which the present invention is applied to the conventional developing device drive device described in FIGS. 4 and 5. It is a corresponding figure. Therefore, members having the same function will be described with the same reference numerals.

In this embodiment, the groove 4 provided in the input gear 3 with which the pin 6 provided on both sides of the intermediate shaft in the radial direction is engaged is a fan-shaped recess 14. The recessed portion has a vertex angle symmetrical with respect to the center of the input gear 3 and at least an angle formed with respect to the center of the axis of the engaging projection 13 having the tapered surfaces of the input joint 7 and the developing joint 10.

Therefore, when the developing device is driven, as shown in FIG. 2, when the main motor 1 is driven, the input gear 3 rotates counterclockwise through the motor gear 2 and is planted on the intermediate shaft 5. The pin 6 is brought into contact with the upstream end wall of the fan-shaped recessed portion 14, and the driving force is transmitted in a state where the main motor 1 and the intermediate shaft 5 are drivingly interlocked with each other, and the intermediate shaft 5 and thus the input joint 7 is rotated counterclockwise. The developing joint 10 that rotates and has a protrusion that engages with the tapered protrusion of the input joint rotates counterclockwise to rotate the developing device drive shaft and develop.

When the motor 1 is stopped and the developing machine is stopped,
The intermediate shaft 5 and the developing device drive shaft stop while maintaining the positional relationship during driving when the pin 6 is engaged with the upstream end wall of the fan-shaped recessed portion 14. Fig. 1 shows the situation. This state is usually maintained even when the developing machine is pulled out.

When the developing machine is replaced or re-installed after maintenance is completed, the input joint 7 and the developing joint 1
When the 0 taper protrusions abut each other, the developing joint 10 side is difficult to rotate due to the resistance of the developer filled in the developing machine, but the intermediate shaft 5 side input joint 7
Since the pin 6 can freely rotate in the fan-shaped recess 14,
As shown by the arrow in FIG. 3, the main motor 1 and the intermediate shaft 5 are easily turned from the upstream side to the downstream side to be in a non-interlocking state. At this time, the tip of the tapered protrusion abuts on the disk surface of the other joint, and the developing machine is set at a predetermined position in the apparatus main body.

During driving, the motor 1 rotates and the motor gear 2
When the input gear 3 rotates in the counterclockwise direction as shown in FIG. 2 through the, the power is transmitted after the upstream edge wall of the fan-shaped recess abuts on the pin 6 and becomes in a driving interlocking state.

In the above embodiments, the member provided with the fan-shaped recess is a gear, but it may be a sprocket to which power is transmitted by a chain.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of a developing device driving device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state when the apparatus of the embodiment is driven and a developing machine is attached.

FIG. 3 is a perspective view showing a state when the apparatus of the embodiment is driven and a developing machine is attached.

FIG. 4 is a side sectional view showing a configuration of a conventional developing device driving device.

FIG. 5 is a perspective view thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main motor, 2 ... Motor gear (transmission means), 3 ... Input gear, 4 ... Groove (conventional device), 5 ... Intermediate shaft, 6 ... Pin, 7 ... Input joint, 8 ... Developing machine, 9 ... Developing machine Drive shaft, 10 ... Development joint, 11 ... Tapered surface, 12 ... Part of flat surface extending in radial direction, 13 ... Engagement protrusion 14 ... Fan-shaped recess

Claims (1)

[Claims] 1. An input joint having an engaging protrusion provided at one end of a shaft, and a developing joint having an engaging portion having the same shape as the engaging protrusion of the input joint and provided at a drive shaft end of a developing machine. In the image forming apparatus having a developing device mounted on the main body so that the input joint and the developing joint are engaged and rotated on the same axis, the engaging projection has a circumferential direction inclined in the axial direction. And a flat surface extending in the radial direction from the axis and passing through the axis, the tapered surface of the engaging portion of the input joint and the tapered surface of the engaging portion of the developing joint are aligned with each other when mounted on the main body of the developing device. When engaging with each other, the shaft of the input joint and the drive source for driving the shaft of the input joint are made non-interlocked, and the shaft of the input joint and the drive source for driving the shaft of the input joint are interlocked. In this case, the flat surface of the engaging portion of the input joint and the flat surface of the engaging portion of the developing joint are engaged,
An image forming apparatus, wherein the driving force of the driving source is interlocked with a driving shaft of a developing machine.