JP4514170B2 - Coupling device and image forming apparatus having the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coupling device and an image forming apparatus including the same, and more particularly to a device configured to couple one coupling to the other coupling while drawing a non-linear trajectory.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine, functional units, functional parts, and the like are provided on the apparatus main body so as to be able to be opened and closed or separated in order to remove a jam sheet and improve maintenance.
[0003]
Here, in order to be able to open / close or separate from the apparatus main body, for example, a paper feed roller or the like is rotated with respect to a paper feed unit which is an example of a functional unit. The drive is supplied through a detachable coupling from the viewpoint of cost, downsizing of the apparatus, and the like.
[0004]
By the way, in the conventional image forming apparatus, as a unit separation method, for example, a unit drawing method for pulling out the unit U from the apparatus main body 80 as shown in FIG. 5 is often used. Normally, as shown in FIG. 6, the unit pull-out direction coincides with the axial direction of the drive shafts of the apparatus main body side (drive side) and unit side (driven side) couplings 500A and 500B and driven shafts 502A and 502B. .
[0005]
Here, normally, the apparatus main body side and unit side couplings 500A and 500B have at least two convex drive transmission claws 501a and 501b at positions symmetrical to the drive shaft and the driven shafts 502A and 502B. When the unit (not shown) is inserted into the apparatus main body and the apparatus main body side coupling 500A is rotated in a state where it is in a predetermined position, the claws 501a of the apparatus main body side coupling 500A are connected to the unit side coupling. The 500B claw 501b is urged in the rotational direction so that drive transmission to the unit side is performed.
[0006]
In addition, one side of the apparatus main body side and the unit side coupling 500A, 500B, for example, as shown in the figure, the main body side coupling 500A is provided with a spring 504a for urging the coupling 500A in the axial direction of the drive shaft 502A. A retraction mechanism 504 is provided.
[0007]
Here, by providing such a retracting mechanism 504, when the claws of the apparatus main body side and the unit side couplings 500A and 500B collide with each other when the unit is housed, the apparatus main body side coupling 500A is retracted in the drive shaft direction. It is supposed to be.
[0008]
Then, after the apparatus main body side coupling 500A is retracted in this way, when the drive shaft 502A starts to rotate, and the apparatus main body side coupling 500A rotates accordingly, the claws come off from the facing state, and the force of the spring 504a Thus, the claws 501a and 501b of the couplings 500A and 500B are adjacent to each other as shown in FIG.
[0009]
Accordingly, when the apparatus main body side coupling 500A rotates, the claws 501b of the unit side coupling 500B are pressed by the claws 501a of the apparatus main body side coupling 500A, the unit side coupling 500B rotates, and the drive shaft 502A rotates. It is transmitted to the driven shaft 502B.
[0010]
[Problems to be solved by the invention]
By the way, in the conventional image forming apparatus provided with the coupling device having such a configuration, the unit U is provided so as to be rotatable in the horizontal direction with respect to the apparatus main body 80 as shown in FIG. When removing the jam sheet or performing maintenance, there is one in which the unit U is opened and rotated as shown in FIG.
[0011]
The unit U shown in FIG. 9 is a manual paper feed unit having a paper feed roller 525, a transport roller 526, etc., as shown in FIG. 9 , and the drive shaft 502B is for driving the transport roller 526 to rotate. is there. Reference numeral 527 denotes a main body drive unit for driving the apparatus main body side coupling 500A.
[0012]
Here, when such a unit U is horizontally opened to be opened and then closed, the claws 501a and 501b of the apparatus main body side and the unit side coupling 500A and 500B are connected to each other as shown in FIG. The unit U is set in the apparatus main body 80 in a state perpendicular to the rotation shaft 503 and on a plane including the drive shaft and the driven shafts 502A and 502B.
[0013]
When the unit U is set in this way, the unit side coupling 500B is not linear, but is coupled to the driving side coupling 500A while drawing a non-linear circular orbit around the rotation shaft 503. Therefore, at the time of coupling, as shown in the figure, the claws 501b of the unit side coupling 500B come into contact with the side surfaces of the apparatus main body side coupling 500A, and the claws are fitted into each other so that they cannot be removed, and the retracting means 504 is provided. However, the apparatus main body side coupling 500A may not be retracted.
[0014]
Here, when the apparatus main body side coupling 500A cannot be retracted as described above, the couplings 500A and 500B are set with the misalignment, and the drive shaft 502A is rotated in this state. As shown in FIG. 10, a phenomenon that the unit U undulates around the axis, that is, a so-called dancing coupling phenomenon occurs, and the unit U and the main body drive unit 527 may be greatly damaged.
[0015]
In order to prevent such misalignment, for example, a joint provided with an automatic centering mechanism may be provided. However, when such a joint is provided, the cost increases due to an increase in the number of parts, and the assembly work becomes complicated. Invite to become.
[0016]
Therefore, the present invention has been made in view of such a situation, and an object thereof is to provide a coupling device capable of coupling the coupling without causing misalignment, and an image forming apparatus including the coupling device. To do.
[0017]
[Means for Solving the Problems]
The present invention provides a drive-side coupling that is attached to a drive shaft and includes a plurality of drive-transmission claws, and a driven-side coupling that is attached to a driven shaft and includes a plurality of drive-transmission claws. A coupling device configured to transmit the rotation of the drive shaft to the driven shaft via the drive side coupling and the driven side coupling, the drive side coupling and the driven side coupling, one coupling, rotates relatively arc shape against the other coupling together is provided to couple to the coupling of said other, the one coupling and the other coupling provided on a plane including the rotation center of one of the coupling the said other coupling when said one of the coupling are attached rotates, the one Contacts the far side of the nail from the rotation center before the close side of the nail to the center of rotation of the coupling, that is configured to move by being pressed axially by the distant side of the nail It is characterized by.
[0018]
In the invention, it is preferable that the other coupling is provided with a contact portion that comes into contact first with a claw farther than a claw closer to the center of rotation of the one coupling. It is.
[0019]
According to the present invention, the contact portion is provided on the inner side of the plurality of drive transmission claws of the other coupling, and protrudes toward the one coupling side from the drive transmission claws. The contact portion is formed with an inclined surface for sliding the claw on the far side of the one coupling toward the claw of the other coupling.
[0020]
According to another aspect of the present invention, there is provided an image forming apparatus including a driving unit, a unit driven by driving from the driving unit, and a coupling device that transmits driving of the driving unit to the unit. Any of the above is characterized by the above.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0022]
FIG. 1 is a diagram showing a configuration of a digital copying machine which is an example of an image forming apparatus provided with a coupling device according to an embodiment of the present invention. In the figure, reference numeral 1 denotes a digital copying machine, 1A denotes an apparatus main body of the digital copying machine 1, B denotes a scanning optical system 50a including a light source 52, mirrors 53a to 53f, and a lens 54, and is set on a document table 51. An image reading unit that reads image information of the original G.
[0023]
Further, C is a photosensitive drum 12 that is irradiated with the reading light L from the image reading unit B to form an electrostatic latent image on the surface, and develops the electrostatic latent image formed on the surface of the photosensitive drum 12. Developers 13 and 14 that form toner images, a transfer charger 15 that transfers the toner image formed on the photosensitive drum 12 onto the sheet S, and a separation charger that separates the sheet onto which the toner image has been transferred from the photosensitive drum 12. An image forming unit 2 having 33 and the like is a fixing device 2 for fixing the transferred toner image to the sheet S.
[0024]
In addition, 101 to 104 are sheet feeding cassettes that are sheet storage units, 29 is a sheet feeding roller for conveying the sheets S stored in the sheet feeding cassettes 101 to 104 to the image forming unit C, 30 is a retard roller pair, 21 Reference numerals 24 denote transport rollers.
[0025]
Next, an image forming operation of the digital copying machine 1 configured as described above will be described.
[0026]
First, the light from the light source 52 is irradiated to the original G set on the original table 51, and then the light reflected from the original G is irradiated to the photosensitive drum 12 through the mirrors 53 a to 53 f and the lens 54. Here, the surface of the photosensitive drum 12 is charged by the charger 11 in advance, and an electrostatic latent image is formed on the surface by irradiating the reading light L (reflected light) from the original G in this way. The Next, the electrostatic latent image thus formed on the surface of the photosensitive drum 12 is developed by the developing units 13 and 14 to form a toner image.
[0027]
On the other hand, the sheet S stored in the paper feed cassettes 101 to 104 in parallel with the formation of the toner image is transferred to the photosensitive drum 12 via the paper feed roller 29, the retard roller pair 30 and the transport rollers 21 to 24. Then, the toner image formed on the photosensitive drum 12 is transferred to the sheet S. Next, the sheet S is conveyed to the fixing device 2 by the conveying belt 34 to fix the toner image, and then is discharged onto a discharge tray (not shown).
[0028]
In the figure, reference numeral 201 denotes a manual paper feed unit provided in the apparatus main body 1A so that copying can be easily performed on other sheets S which are not stored in the paper feed cassettes 101 to 104. The paper feed unit 201 includes a paper feed roller 25, a transport roller 26, a separation roller 27, and other parts necessary for paper feed (not shown).
[0029]
Further, as shown in FIG. 2, the manual paper feed unit 201 is attached to the apparatus main body 1A so as to be rotatable in the horizontal direction around the rotation center axis 202, and a jam has occurred in the manual paper feed unit 201. In the case of jam handling in the case, or maintenance such as manual feed unit internal cleaning or parts replacement by a service person, the manual feed unit 201 is rotated and released in the horizontal direction, Alternatively, maintenance and the like can be easily performed.
[0030]
On the other hand, in the figure, reference numeral 200 denotes a coupling device. The coupling device 200 is a coupling 204 (hereinafter referred to as a manual feed unit) provided on one end of a drive shaft 26a of a transport roller 26 that is a driven shaft. , A unit side coupling) and a coupling 203 on the apparatus main body side that transmits the drive of the drive motor M provided in the apparatus main body 1A to the conveying roller 26 in combination with the unit side coupling 204 (hereinafter referred to as a main body side cup). Ring).
[0031]
Reference numeral 206 denotes a drive shaft of the main body side coupling 203 that rotates the main body side coupling 203 and supports the main body side coupling 203 so as to be movable in the axial direction. Reference numeral 207 denotes an electromagnetic wave attached to the drive shaft 206. The drive of the drive motor M that is a clutch and is transmitted by the electromagnetic clutch 207 via the drive transmission belt 211 is selectively transmitted to the main body side coupling 203 via the drive shaft 206. Since the drive shaft 206 of the main body side coupling 203 is driven only when necessary via the electromagnetic clutch 207, it is normally in a rotatable state.
[0032]
Reference numeral 205 denotes a retraction mechanism provided with a spring 205 a attached to the drive shaft 206. The main body side coupling 203 is urged toward the manual paper feed unit by the spring 206a. When the manual paper feed unit 201 is opened, the main body side coupling 203 is as shown in FIG. It protrudes toward the manual feed unit.
[0033]
By the way, when the main body side coupling 203 is connected to the unit side coupling 204, the main body side coupling 203 is positioned adjacent to the claws 209a and 209b of the unit side coupling 204. The claws 210a and 210b for rotating the unit side coupling 204 by pressing the pins 209a and 209b are provided. In this embodiment, the claws 210a and 210b are in contact with each other as shown in FIG. The pushing-in part 208 which is a part is provided.
[0034]
Here, when closing the opened manual paper feeding unit 201, the push-in portion 208 first comes into contact with a claw 209a far from the rotating shaft 202 of the unit side coupling 204 (hereinafter referred to as a far claw) 209a. Thus, when closing the manual feed unit 201 in this way, first, the distant claw 209a of the unit side coupling 204 is brought into contact with the pushing portion 208, whereby the main body side coupling 203 is brought into contact with the spring 205a of the retraction mechanism 205. It can be pushed into the main body while resisting.
[0035]
Note that the push-in portion 208 protrudes closer to the manual feed unit than the claws 210a and 210b of the main body side coupling 203 so as to be able to contact the distant claws 209a of the unit side coupling 204 first.
[0036]
Next, the operation of the coupling device 200 configured as described above will be described.
[0037]
When the manual feed unit 201 is rotated in the closing direction after the jam processing or the like is finished, the claws 210a and 210b of the main body side coupling 203 and the claws 209a and 209b of the unit side coupling 204 are perpendicular to the rotation shaft 202. Since the unit-side coupling 204 draws a circular orbit that is a non-linear orbit about the rotation axis 202 as the manual feed unit 201 rotates, the main body-side coupling is drawn. It approaches 203.
[0038]
Thereafter, when the manual sheet feeding unit 201 is further rotated, as shown in FIG. 2, first, the distant claw 209 a far from the center of the track of the unit side coupling 204 comes into contact with the pushing portion 208 of the main body side coupling 203. To do. Here, by first bringing the distant claw 209a into contact with the push-in portion 208 as described above, when the manual feed unit 201 is further rotated, the main body side coupling 203 is moved to the apparatus main body side as shown in FIG. It gets pushed.
[0039]
Then, when the manual sheet feeding unit 201 is further rotated in the closing direction by pushing in the main body side coupling 203 in this way, a claw on the side close to the rotation shaft 202 of the unit side coupling 204 ( 209b (hereinafter referred to as “rotating shaft side claw”) does not come into contact with the side surface of the claw 210b on the side close to the rotating shaft 202 of the main body side coupling 203.
[0040]
Therefore, the rotation shaft side claw 209b of the unit side coupling 204 and the claw 210b on the side close to the rotation shaft 202 of the main body side coupling 203 are fitted and cannot be removed, so that the main body side and the unit side couplings 203, 204 are removed. The locked state can be prevented.
[0041]
In the present embodiment, for example, as shown in FIG. 3, an inclined surface 208 a is formed at the tip of the push-in portion 208 that abuts on the distant claw 209 a of the unit side coupling 204.
[0042]
By forming such an inclined surface 208a, the distant claw 209a slides along the inclined surface 208a before or after the main body side coupling 203 is pushed into the predetermined position of the apparatus main body 1A. It moves away from 208 and moves toward the claw 210a of the main body side coupling 203 as shown in FIG. Thereby, after this, when the unit side coupling 204 rotates, the claws 209a, 209b and the claws 210a, 210b can easily slip and shift to a normal engagement state.
[0043]
As described above, when the push-in portion 208 is provided in the main body side coupling 203 and the manual sheet feeding unit 201 is closed, the remote claw 209a of the unit-side coupling 204 is first brought into contact with the push-in portion 208, thereby The rotation shaft side claw 209b of 204 can be coupled to the unit side coupling 204 while pushing in the main body side coupling 203 without locking.
[0044]
As a result, it is possible to easily prevent coupling coupling failures caused by misalignment between the drive shafts 26a and 206 of the main body side coupling 203 and the unit side coupling 204, and a dancing coupling phenomenon resulting from this. It is possible to prevent the coupling device 200 from being broken or damaged due to the coupling.
[0045]
In the above description, the case where the push-in portion 208 and the retracting mechanism 205 are provided in the main body side coupling 203 has been described. However, the present invention is not limited to this, and the push-in portion 208 and the retracting portion in the unit-side coupling 204 are described. Even if the mechanism 205 is provided, the same effect can be obtained.
[0046]
【The invention's effect】
As described above, according to the present invention, when one of the driving side coupling and the driven side coupling is coupled to the other coupling while drawing a non-linear trajectory, the one coupling is coupled. By making the claw on the side far from the center of the track in contact with the other coupling before the claw on the side near the center of the track, the coupling can be coupled without causing misalignment.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of a digital copying machine that is an example of an image forming apparatus including a coupling device according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration of the coupling device.
FIG. 3 is a diagram illustrating a state of a coupling device immediately before a manual sheet feeding unit provided in the image forming apparatus is closed.
FIG. 4 is a diagram illustrating a state of the coupling device when the manual sheet feeding unit is closed.
FIG. 5 is a perspective view of a conventional unit drawer type image forming apparatus.
FIG. 6 is a perspective view showing a configuration of a coupling device of the conventional image forming apparatus.
FIG. 7 is a perspective view showing a drive transmission state of the coupling device.
FIG. 8 is a perspective view of a conventional unit rotation type image forming apparatus.
FIG. 9 is a diagram illustrating a configuration of a coupling device of the unit rotation type image forming apparatus.
FIG. 10 is a diagram for explaining a defect in the coupling device of the unit rotation type image forming apparatus.
[Explanation of symbols]
1 Digital Copier 1A Apparatus Main Body 26a (Conveying Roller) Drive Shaft 200 Coupling Device 201 Manual Feed Unit 202 Unit Rotating Shaft 203 Main Body Side Coupling 204 Unit Side Coupling 206 Drive Shaft 207 Drive Transmission Clutch 208 Pushing Part 209a 209b Unit side coupling claws 210a 210b Body side coupling claws M Drive motor

Claims (4)

A drive side coupling that is attached to the drive shaft and includes a plurality of drive transmission claws and a driven side coupling that is attached to the driven shaft and includes a plurality of drive transmission claws are detachably coupled. In the coupling device, the rotation of the drive shaft is transmitted to the driven shaft via the drive side coupling and the driven side coupling.
One of the coupling of said drive-side coupling and the driven side coupling, together rotated relatively arc shape against the other coupling is provided to couple to the coupling of said other, The one coupling and the other coupling are provided on a plane including a rotation center of the one coupling, and when the one coupling is rotated and coupled, contacts the far side of the nail from the rotation center before the close side of the nail to the center of rotation of one of the coupling the, and is configured to move by being pressed axially by the distant side of the nail A coupling device. 2. The cup according to claim 1, wherein the other coupling is provided with a contact portion that first comes into contact with a claw farther than a claw closer to a rotation center of the one coupling. Ring device.   The contact portion is provided inside the plurality of drive transmission claws of the other coupling, protrudes toward the one coupling side than the drive transmission claws, and further, the contact portion includes 3. The coupling device according to claim 2, wherein an inclined surface is formed for sliding a claw on the far side of the one coupling toward the claw of the other coupling. In an image forming apparatus comprising: a drive unit; a unit driven by driving from the drive unit; and a coupling device that transmits the drive of the drive unit to the unit.
The image forming apparatus according to claim 1, wherein the coupling device is the device according to claim 1.

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