JPH0540523Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a coupling mechanism between a drive shaft and a rotating body fitted to the drive shaft, such as a photosensitive drum of an electrophotographic copying machine.

(Prior Art) A photosensitive drum of an electrophotographic copying machine usually has an electrostatic latent image formed on its surface, and the electrostatic latent image is developed with toner conveyed on the circumferential surface of a developing roller. The photosensitive drum can be pulled out from the main body of the copying machine in the axial direction for maintenance and inspection or to remove jammed paper. For this reason, the photoreceptor drum
It is configured to be detachable from the drive shaft that transmits rotational force. Normally, the photoreceptor drum is
By moving it in the axial direction, it is brought into engagement with or disengagement from the drive shaft. A one-way clutch is used to connect the drive shaft and the photoreceptor drum in order to facilitate attachment and detachment of the two and to reliably transmit power from the drive shaft to the photoreceptor drum. A one-way clutch allows the fitted shaft to freely rotate in only one direction, and the one-way clutch allows the fitted drive shaft to freely rotate only in the opposite direction to the rotational drive direction. The clutch is attached to the photosensitive drum and configured to be detachable from the drive shaft. When the one-way clutch and the photoreceptor drum are fitted together and the drive shaft is rotated, the one-way clutch works to restrict rotation in the direction of rotation, and as a result, the one-way clutch becomes integral with the drive shaft. Rotate and rotate. Therefore, the photoreceptor drum to which the one-way clutch is attached also rotates together.

Further, a locking tool is attached to the drive shaft so as to be able to slide in the axial direction and rotate integrally with the drive shaft, and an engagement recess that can be engaged with the locking tool is formed in the photoreceptor drum to engage the two. A method has also been adopted in which rotation is transmitted by In this method, a slight gap is formed between the two when engaged so that the photoreceptor drum can be easily attached to and detached from the drive shaft.

(Problem to be solved by the invention) By the way, during a copying operation, the photosensitive drum tends to rotate faster than the rotational speed of the drive shaft due to the action of the rotational force of the developing roller that rotates at high speed against the photosensitive drum. do. As a result, in a coupling mechanism using a one-way clutch, the photoreceptor drum can freely rotate in a direction in which the photoreceptor drum is ahead of the drive shaft, so that the photoreceptor drum is ahead of the other. In addition, in the case of a connection using a locking tool and an engaging recess, the rotation of the photoreceptor drum is prevented to some extent, but during a copying operation, the photoreceptor drum rotates unevenly due to the gap formed between the two. There is a risk. In this way, a clear copy image cannot be obtained due to the photoreceptor drum 30 moving ahead of itself or due to uneven rotation of the photoreceptor.

The present invention solves the above conventional problems, and its purpose is to facilitate the attachment and detachment of the drive shaft and the rotating body, and to ensure that the rotational force of the drive shaft is transmitted to the photoreceptor drum. The object of the present invention is to provide a connection mechanism that can prevent uneven rotation of a rotating body.

(Means for Solving the Problems) The present invention provides a coupling mechanism for transmitting drive transmission force from a drive shaft to a rotating body on the driven side, and includes an engaging shaft portion at the tip of the drive shaft. and a lock fitted to the proximal end side of the engagement shaft portion of the drive shaft so as to be slidable in the axial direction and rotatable integrally with the drive shaft; a one-way clutch attached to the rotating body so that the one-way clutch can freely rotate in a direction opposite to the rotational driving direction thereof; an engagement recess disposed on the rotating body so that the tool can be engaged with the engagement recess;
an elastic body interposed between the engagement recess and the locking device on the opposite side of the surfaces that come into contact with each other when the two engage and rotate; This achieves the above objective.

(Example) The present invention will be described below with reference to examples.

The coupling mechanism between a drive shaft and a rotating body according to the present invention is applied, for example, to a coupling mechanism between a photosensitive drum and a drive shaft of an electrophotographic copying machine. As shown in FIGS. 1 to 4, one of the drive shafts 10 has an engaging shaft portion 12 at its distal end, and is locked to the proximal end of the engaging shaft portion 12 of the drive shaft 10. A tool 20 is provided. A one-way clutch 40 and an engagement recess 50 are disposed in a flange portion 31 at the end of the photosensitive drum 30, which is the other rotating body on the driven side.

The drive shaft 10 is normally disposed on the back side of the copying machine main body, and is rotated in one direction by transmitting power from the main motor of the copying machine.

The locking tool 20 includes a disc-shaped pedestal 21 mounted on the proximal end side of the engagement shaft portion 12 of the drive shaft 10 so as to be slidable in the axial direction thereof, and two axially symmetrical positions of the pedestal 21. It has an engaging protrusion 23 protruding from the tip. The outer peripheral surface of the engaging protrusion 23 is flush with the outer peripheral surface of the base 21. The locking tool 20 is connected to the drive shaft 10
The pin 1 is fixed to the engagement shaft portion 12 in a key groove 21a formed on the inner circumferential surface of the base 21 so as to rotate integrally with the pin 1 and to be able to slide in the axial direction.
3 is fitted. The portion of the engagement shaft portion 12 where the pin 13 is disposed is preferably chamfered. The locking tool 20 is biased toward the distal end by a push spring 11 fitted onto the drive shaft 10 .

An engagement hole 32 is formed at the axial center of the flange portion 31 of the photoreceptor drum 30 . At two axially symmetrical positions of the engagement hole 32, engagement recesses 50 are formed into which the engagement protrusions 23 of the locking tool 20 can fit. An engagement hole 3 adjacent to the engagement recess 50
A one-way clutch 40 is attached to the innermost side of the drive shaft 10.
The engagement shaft portion 12 can be fitted thereto. one way clutch 4
0 supports the fitted shaft rotatably in one direction.

The one-way clutch 40 is a known one, as shown in FIG.
It has a plurality of rollers 43, 43, . On the inner periphery of the outer ring 41, inclined surfaces 41a, 4 are provided at intervals in the circumferential direction.
1a,... are formed. Each inclined surface 41a is inclined toward the center in a direction opposite to the rotational driving direction (that is, clockwise when viewed from the drive shaft 10 side as shown by arrow A in FIG. 5). Each roller 43 is interposed between each inclined surface 41a and the outer circumferential surface of the engagement shaft portion 12, respectively. Each roller 43 has a spring 44 formed in a retaining ring 44.
An elastic force along the rotational drive direction is given by a.

When the drive shaft 10 rotates in the rotation driving direction A, each roller 43 engages with the inclined surface along the inclined surface 41a, as shown by the solid line in FIG. 5, due to the elastic force of the spring 44a. It bites in between the outer circumferential surface of the shaft portion 12. Therefore, the rotational power from the drive shaft 10 is transmitted to the photoreceptor drum 30 via the rollers 43, and the photoreceptor drum 30 is rotationally driven integrally with the engagement shaft portion 12.

On the other hand, when a force acts on each roller 43 in the direction opposite to the rotational driving direction of the engagement shaft portion 12, for example, when the engagement shaft portion 12 is rotated in the opposite direction to the rotational driving direction, Alternatively, when the engagement shaft portion 12 is rotating in the rotation drive direction, the drum 30 rotates in the same direction at a higher speed than the rotation of the engagement shaft portion 12, and the drum 30 attempts to move ahead in the same direction. teeth,
Each roller 43 is, as shown by the two-dot chain line in FIG.
It is located in a wide space between the inclined surface 41a of the outer ring 41 and the engagement shaft portion 12, and can be in rolling contact with the outer circumferential surface of the engagement shaft portion 12. As a result, the rotation of the engagement shaft portion 12 is absorbed by each roller 43 and is not transmitted to the outer ring 41, so that the drum 30 does not rotate.

In the engagement recess 50, a material made of high hardness, for example, is provided on the side opposite to the surface where the engagement protrusions 23 of the locking tool 20 come into contact with each other due to rotation of the engagement protrusions 23 when they are engaged. Elastic bodies 60 and 60 made of rubber or the like are interposed at two axially symmetrical positions. As the elastic bodies 60 and 60, for example, a high hardness rubber having a hardness of 90 (JIS A), a plate spring, or the like is used.

With the connection mechanism having such a configuration, the drive shaft 10
The rotational force of the photosensitive drum 3 is generated by the engagement of the engagement shaft 12 with the one-way clutch and the engagement of the engagement protrusion 23 with the engagement recess 50.
0. Further, the photoreceptor drum 30 is easily pulled out in the axial direction and separated from the drive shaft 10 during maintenance and inspection work. Then, when the work is finished, the photosensitive drum 30 is moved to the drive shaft 10.
pushed laterally. As a result, the drive shaft 10
The engagement shaft portion 12 of the locking tool 20 attached to the tip of the
is fitted into the engagement hole 32 formed in the flange portion 31 of the photoreceptor drum 30 . The engagement shaft portion 12 is then fitted into the one-way clutch 40. When the photoreceptor drum 30 is further pushed in, the engagement shaft portion 1
The engagement protrusion 23 at the base end of 2 contacts the end surface of the flange portion 31, but by appropriately rotating the photoreceptor drum 30, the engagement protrusion 23 is Together with this, the engagement recess 50 is engaged. At this time, a slight gap is formed between the engagement recess 50 and the engagement shaft 23.

When the drive shaft 10 is rotationally driven in this state, each roller 43 bites between the outer ring 41 and the engagement shaft 12 due to the engagement between the engagement shaft 22 and the one-way clutch 40, and the photosensitive The body drum 30 is the drive shaft 10
The engagement protrusion 23 and the engagement recess 50
The rotation of the drive shaft 10 is also transmitted to the photoreceptor drum 30, and the photoreceptor drum 30 rotates.

In this way, when a copying operation is performed with the drive shaft 10 and the photoreceptor drum 30 connected, the photoreceptor drum 30 rotates at a high speed of the developing roller that is in sliding contact with the photoreceptor drum 30 . It precedes the rotation by the gap formed between the two. However, the side opposite to the surface that contacts each other during rotation between the engagement recess 50 and the engagement protrusion 23,
That is, since the elastic bodies 60 and 60 are provided on the sides that come into contact with each other when moving forward, the elastic bodies 60 and 60 are
is pressed. In such a state, if the drive shaft 10 rotates faster than the photosensitive drum 30,
Since driving in the rotational direction is restricted by the one-way clutch 40, uneven rotation does not occur even if there is a gap between the two, and uneven rotation of the photosensitive drum during copying operations is prevented. Note that, since an idling operation is normally performed before starting a copying operation, the advance phenomenon due to the initial gap does not cause any problem during the copying operation.

On the other hand, when power is transmitted by the one-way clutch, each roller 43 of the one-way clutch 40 is connected to the outer ring 4.
1 and the engagement shaft portion 12. When each roller 43 bites firmly between the outer ring 41 and the engagement shaft 12 in this way, the engagement shaft 1
2, there is a possibility that the one-way clutch 40 will not be released. However, between the engagement protrusion 23 and the engagement recess 50, there are elastic bodies 60 and 60 on the side opposite to the surface where the two come into contact when the two engage and rotate.
are interposed, the elastic bodies 60 and 6
0 is compressed and elastically deformed, that is, the photoreceptor drum 30 is forcibly rotated slightly in the direction of rotation of the engagement shaft portion 12, or engaged in the opposite direction to the rotational driving direction of the engagement shaft portion 12. When the shaft portion 12 is forcibly rotated, the outer ring 41 of the one-way clutch 40
Each roller 43 is inserted into the wide space between the engagement shaft portion 12 and the
is moved, and the rollers 43 that have been firmly wedged between the outer ring 41 and the engaging shaft portion 12 are released. As a result, the engagement shaft portion 12 can be easily disengaged from the one-way clutch 40.

(Effects of the invention) The coupling mechanism of the invention has the following features: the engagement between the engagement shaft part of the drive shaft and the one-way clutch, and the engagement between the engagement protrusion of the locking tool attached to the drive shaft and the rotating body side. Since the rotation of the drive shaft is transmitted to the rotating body by both the engagement with the engagement recess, the rotation of the drive shaft is reliably transmitted to the rotating body. Since the engagement protrusion and the engagement recess are engaged through the elastic body, there is no risk that the rotating body will move ahead of itself or that the rotating body will rotate unevenly when the two are engaged and rotated. Even when the one-way clutch and the drive shaft are firmly wedged together, by compressing the elastic body and deforming the elastic body,
Since the tight fitting between the two is released, the rotating body can be easily attached to and detached from the drive shaft.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the coupling mechanism of the present invention, FIG. 2 is a longitudinal sectional view thereof, FIG. 3 is a sectional view taken along the - line in FIG. 2, and FIG. 4 is a sectional view taken along the - line in FIG. FIG. 5 is an enlarged sectional view taken along line V-V in FIG. 2. 10... Drive shaft, 12... Engagement shaft portion, 20...
Locking tool, 23... Engaging protrusion, 30... Photosensitive drum, 40... One-way clutch, 41... Outer ring, 4
3... Roller, 50... Engagement recess, 60... Elastic body.

Claims (1)

[Claims for Utility Model Registration] A coupling mechanism for transmitting drive transmission force from a drive shaft to a driven rotating body, comprising: an engaging shaft portion at the tip of the drive shaft; A locking tool is fitted to the proximal end side of the engagement shaft so that it can slide in the axial direction and rotate integrally with the drive shaft, and the engagement shaft fits and rotates. a one-way clutch attached to the rotating body so as to be able to freely rotate in a direction opposite to the driving direction; and the locking tool can be engaged when the one-way clutch and the engagement shaft are fitted together. an engaging recess provided on the rotating body, and an intervening device between the engaging recess and the locking device on the opposite side of the surfaces that come into contact with each other when the two engage and rotate. A coupling mechanism between a drive shaft and a rotary body, comprising: an elastic body made of elastic material;