JP7102795B2 - Drive transmission mechanism, drive device and image forming device - Google Patents

Description

The present invention relates to a drive transmission mechanism, a drive device and an image forming device.

Conventionally, an image forming apparatus includes a photoconductor drum, a developing apparatus, and the like, and includes a driving device for driving an image forming unit configured to be detachable from the apparatus main body. The drive device is configured to release the transmission of the rotational driving force of the image forming unit to the photoconductor drum, the developing device, etc. when the front cover of the device body is opened / closed to attach / detach the image forming unit. .. As a technique related to such a drive device, those disclosed in Patent Document 1 and Patent Document 2 and the like have already been proposed.

Patent Document 1 is provided with a rotating body having a rotating shaft and a spherical shape provided at the end of the rotating shaft or the end of the rotating shaft of a transmission member for transmitting a driving force to the rotating shaft, and is open to one side. The engagement portion has a concave portion and at least one first groove portion recessed in a direction intersecting the rotation axis direction is formed in the concave portion, and the engagement portion is arranged at a rotation center arranged along the rotation axis direction. A hole portion opened to the joint portion side is formed, and at least one second groove portion recessed in the direction intersecting the rotation axis direction is formed in the hole portion, and the driving force transmission member rotationally driven by the driving source. A first spherical portion is formed at one end of the cylindrical shaft portion in the axial direction, a second spherical portion is formed at the other end, and the outer peripheral surface of the first spherical portion is axially separated from the first groove portion. At least one first convex portion that can be engaged with is formed, and at least one second convex portion that engages with the second groove portion is formed on the outer peripheral surface of the second spherical portion, and the engaged portion is formed. And a connecting member that connects the driving force transmitting member and the driving force transmitting member so as to be movable in the eccentric direction and the axial direction and can be rotationally transmitted, and an urging member provided in the hole portion to urge the connecting member toward the engaged portion side. It is configured to have means and.

Patent Document 2 is provided with a bearing support portion that supports the bearing and is open so that the bearing can be removed in a first direction intersecting the rotating shaft supported by the bearing, and one end of the rotating shaft. It has a drive side shaft joint that transmits a driving force to the rotating shaft by being connected to the rotating shaft side shaft joint, and a contact member having a bearing contact portion that contacts the bearing, and the bearing contact portion has a bearing contact portion. When the contact member is located at the first position, the contact member contacts the bearing so as to restrict the movement of the bearing in the first direction, and the contact member moves from the first position to the rotating shaft. When the bearing moves in the second direction intersecting with the bearing, the bearing is separated from the bearing so as not to restrict the movement of the bearing in the first direction. When it is located at the position, it is pushed toward the rotating shaft side bearing so as to be connected to the rotating shaft side bearing, and the contact member moves from the first position to the second direction. In this case, it is configured to be pulled back away from the rotary shaft side bearing.

Japanese Unexamined Patent Publication No. 2013-195961 Japanese Unexamined Patent Publication No. 2013-238815

An object of the present invention is to compare a drive structure including a drive force transmitting member that is rotationally driven by a drive source and a connecting member that is eccentrically and axially movable and rotationally transmitted to the driving force transmitting member. Therefore, the dimension along the axial direction of the drive transmission means for transmitting and releasing the rotational driving force is reduced.

The invention according to claim 1 comprises a drive means having a drive transmission shaft provided with a plurality of convex portions on the outer periphery and being rotationally driven.
A drive that is movably mounted along the axial direction of the drive transmission shaft through a mounting hole having a plurality of concave portions on the inner circumference that engage with the plurality of convex portions, and a rotational driving force is transmitted from the driving means. Means of communication and
A gap forming portion provided at the tip of the drive transmission shaft and the base end of the mounting hole to form a gap that allows the drive transmission shaft to tilt in a state where the convex portion and the concave portion are engaged with each other.
Covering means arranged on one side surface along the axial direction of the driving means, and
With
The covering means is a drive transmission mechanism having a sliding portion that contacts and rotatably supports the cylindrical portion of the drive means toward the inside along the axial direction of the drive means .

The invention according to claim 2, wherein the gap forming portion has a different angle allowing the inclination of the drive transmission shaft depending on the engagement state between the convex portion and the concave portion. It is a mechanism.

The invention according to claim 3 is claimed in claim 2, wherein the gap forming portion is composed of a rounded surface provided at the tip of a drive transmission shaft of the driving means and a cut surface provided at the base end of the mounting hole. The drive transmission mechanism described.

The invention according to claim 4 is the drive transmission mechanism according to claim 1, wherein the drive transmission means is urged by the urging means in a direction away from the drive means.

The invention according to claim 5 is the drive transmission mechanism according to claim 4, wherein the urging means is arranged on the outer periphery of the drive transmission shaft of the drive means.

According to a sixth aspect of the present invention, the drive transmission means has a plurality of second convex portions for transmitting a driving force to another drive transmission means on the outer periphery of the tip end portion of the drive transmission shaft. The driving force transmission mechanism according to any one of 5 to 5.

The invention according to claim 7 is the driving force transmission mechanism according to claim 6, wherein the plurality of second convex portions are provided at positions corresponding to the plurality of convex portions of the drive transmission shaft.

The invention according to claim 8 includes a driving source and a driving source.
Driven means to be driven by transmitting rotational driving force from the drive source, and
A drive transmission means for transmitting and releasing a rotational driving force from the drive source,
With
A drive device using the drive transmission mechanism according to any one of claims 1 to 7 as the drive transmission means.

The invention according to claim 9 includes an image forming means and an image forming means.
The driving means for driving the image forming means and
With
An image forming apparatus using the driving device according to claim 8 as the driving means.

According to the invention described in claim 1, a driving force transmitting member that is rotationally driven by a driving source and a connecting member that is movable in the eccentric direction and the axial direction and is rotatably connected to the driving force transmitting member. Compared with the provided drive structure, the dimension of the drive transmission means for transmitting and releasing the rotational driving force along the axial direction can be reduced.
Further, according to the invention described in claim 1, the covering means has a sliding portion that contacts and rotatably supports the cylindrical portion of the driving means toward the inside along the axial direction of the driving means. The dimension along the axial direction of the drive transmission means can be further reduced as compared with the case where the drive transmission means is not provided.

According to the second aspect of the present invention, the gap forming portion has a drive transmission shaft as compared with a case where the angle at which the inclination of the drive transmission shaft is allowed is not changed depending on the engagement state of the convex portion and the concave portion. Can be easily engaged with the drive transmission means.

According to the third aspect of the present invention, the gap forming portion is compared with the case where the gap forming portion is not composed of a rounded surface provided at the tip of the drive transmission shaft of the driving means and a cut surface provided at the base end of the mounting hole. Therefore, the gap forming portion can be easily formed.

According to the invention described in claim 4, the drive transmitting means easily separates the drive transmitting means from the driving means as compared with the case where the driving transmitting means does not include the urging means for urging in the direction away from the driving means. be able to.

According to the fifth aspect of the present invention, the urging means can be easily arranged as compared with the case where the urging means is not arranged on the outer periphery of the drive transmission shaft of the driving means.

According to the invention described in claim 6, the drive transmitting means does not have a plurality of second convex portions for transmitting a driving force to other drive transmitting means on the outer periphery of the tip portion, as compared with the case where the drive transmitting means does not have a plurality of second convex portions. The driving force can be easily transmitted.

According to the invention described in claim 7, the plurality of second convex portions are not provided at positions corresponding to the plurality of convex portions of the drive transmission shaft, and the transmission accuracy of the rotational driving force is improved as compared with the case where the plurality of second convex portions are not provided. Can be made to.

According to the invention described in claim 8 , the dimension along the axial direction of the drive device is smaller than that in the case where the drive transmission mechanism according to any one of claims 1 to 7 is not used as the drive transmission means. can do.

According to the invention described in claim 9 , the size of the device can be reduced as compared with the case where the driving device according to claim 8 is not used as the driving means.

FIG. 5 is an external perspective view showing an image forming apparatus to which the drive transmission mechanism and the drive device according to the first embodiment of the present invention are applied. It is a schematic block diagram which shows the whole of the image forming apparatus. It is a block diagram which shows the image forming unit in an image forming apparatus. It is a perspective view which shows the image forming unit in an image forming apparatus. FIG. 5 is a schematic configuration diagram showing a state in which the front cover of the image forming apparatus to which the drive transmission mechanism and the drive device according to the first embodiment of the present invention is applied is opened. It is a block diagram which shows the drive apparatus to which the drive transmission mechanism which concerns on Embodiment 1 of this invention is applied. FIG. 5 is a perspective configuration diagram showing a main part of a drive device to which the drive transmission mechanism according to the first embodiment of the present invention is applied. It is sectional drawing which shows the main part of the drive apparatus to which the drive transmission mechanism which concerns on Embodiment 1 of this invention is applied. It is a perspective block diagram which shows the photoconductor drive gear and the photoconductor main coupling. It is a perspective block diagram which shows the developing apparatus drive gear and the developing apparatus main coupling. It is a plane block diagram which shows the developing apparatus drive gear and the developing apparatus main coupling. It is sectional drawing which shows the developing apparatus drive gear and the developing apparatus main coupling. It is a schematic diagram which shows the developing apparatus drive gear and the developing apparatus main coupling. It is a perspective block diagram which shows the developing apparatus drive gear and the developing apparatus main coupling. It is sectional drawing which shows the main part of the drive transmission mechanism of the drive device which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the separated state of the main part of the image forming apparatus to which the driving apparatus which concerns on Embodiment 1 of this invention is applied. It is sectional drawing which shows the connected state of the main part of the image forming apparatus to which the driving apparatus which concerns on Embodiment 1 of this invention is applied. It is a perspective block diagram which shows the fixing device drive gear and the fixing device coupling. It is a perspective block diagram which shows the toner supply drive gear and the toner supply main coupling. It is a perspective block diagram which shows the toner supply coupling and the toner supply connecting member. It is a front view which shows the link member. It is a perspective view which shows the main part of the link member. It is a perspective view which shows the main part of the link member. It is sectional drawing which shows the main part of the drive transmission mechanism which concerns on Embodiment 1 of this invention. It is a perspective block diagram which shows the main part of the drive transmission mechanism which concerns on Embodiment 1 of this invention. It is a perspective block diagram which shows the main part of the drive transmission mechanism which concerns on Embodiment 1 of this invention. It is a block diagram which shows the opening and closing mechanism of a front cover. It is a perspective view which shows the contact action part of a rotating body and a front cover. It is a block diagram which shows the release state of the drive device to which the drive transmission mechanism which concerns on Embodiment 1 of this invention is applied. It is sectional drawing which shows the release state of the drive apparatus to which the drive transmission mechanism which concerns on Embodiment 1 of this invention is applied. It is a perspective block diagram which shows the release state of the drive apparatus to which the drive transmission mechanism which concerns on Embodiment 1 of this invention is applied. It is a perspective block diagram which shows the coupling state of the drive apparatus to which the drive transmission mechanism which concerns on Embodiment 1 of this invention is applied.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Embodiment 1]
1 to 3 show an image forming apparatus to which the drive transmission mechanism and the drive device according to the first embodiment are applied. FIG. 1 shows the overall appearance of the image forming apparatus, FIG. 2 shows an outline of the entire image forming apparatus, and FIG. 3 shows an enlarged view of a main part (image forming unit) in the image forming apparatus. .. In the figure, the arrow X indicates the depth direction along the horizontal direction, Y indicates the vertical direction, and Z indicates the width and row direction along the horizontal direction.

<Overall configuration of image forming apparatus>
The image forming apparatus 1 according to the first embodiment is configured as, for example, a monochrome printer. As shown in FIG. 1, the image forming apparatus 1 includes an apparatus main body 1a formed in a substantially rectangular cuboid shape in which the height is relatively low with respect to the depth. The apparatus main body 1a is provided with a front cover 101 as an example of an opening / closing member on the front surface when the operator operates the image forming apparatus 1 so as to be openable / closable along the directions of arrows B1 and B2. The front cover 101 has a front surface portion 101a arranged in front of the device main body 1a, and an upper surface portion 101b arranged on a part (front side) of the upper end surface of the device main body 1a. The upper surface portion 101b of the front cover 101 is configured to be openable and closable with respect to the apparatus main body 1a independently of the front surface portion 101a. Further, on the upper end surface of the apparatus main body 1a, a paper ejection unit 36 for ejecting the recording paper 5 as an example of the recording medium on which the image is formed is provided in an inclined state. The device main body 1a is formed of exterior covers 102 to 104 including a support structural member and a front cover 101.

As shown in FIG. 2, the image forming apparatus 1 forms an image forming apparatus 10 for forming a toner image developed by toner constituting a developer, and a required record to be supplied to a transfer position of the image forming apparatus 10. The paper feed device 20 for accommodating and supplying the paper 5, the transport device 30 for transporting the recording paper 5 supplied from the paper feed device 20 along the transport path shown by the alternate long and short dash line, and the image drawing device 10. It is provided with a fixing device 40 and the like for fixing the toner image on the transferred recording paper 5.

The image forming apparatus 10 includes a rotating photoconductor drum 11 as an example of an image forming means (image holding means). Around the photoconductor drum 11, each device as an example of the following image forming means is mainly arranged. The main devices are a charging device 12 that charges the peripheral surface (image holding surface) capable of forming an image of the photoconductor drum 11 to a required potential, and image information (image information (image information) on the charged peripheral surface of the photoconductor drum 11. An exposure device 13 that irradiates light based on (signal) to form an electrostatic latent image with a potential difference, and a developing device 14 that develops the electrostatic latent image with a toner of a black color developer to form a toner image. The transfer device 15 transfers the toner image to the recording paper 5, and the drum cleaning device 16 and the like remove and clean the toner and other deposits remaining on the image holding surface of the photoconductor drum 11 after transfer.

The photoconductor drum 11 has an image-holding surface having a photoconductive layer (photosensitive layer) made of a photosensitive material formed on the peripheral surface of a cylindrical or columnar base material to be grounded. As will be described later, the photoconductor drum 11 is supported so that power is transmitted from the drive device and the photoconductor drum 11 rotates in the direction indicated by the arrow A.

The charging device 12 is composed of a contact-type charging roll that is arranged in contact with the photoconductor drum 11. A charging voltage is supplied to the charging device 12. As the charging voltage, when the developing device 14 performs reverse development, a voltage or current having the same polarity as the charging polarity of the toner supplied from the developing device 14 is supplied. As the charging device 12, a non-contact type charging device such as a scorotron arranged on the surface of the photoconductor drum 11 in a non-contact state may be used.

The exposure apparatus 13 irradiates the photoconductor drum 11 with light according to image information by means of a plurality of LEDs (Light Emitting Diodes) as light emitting elements arranged along the axial direction of the photoconductor drum 11 to perform an electrostatic latent image. Consists of an LED printhead that forms. The exposure device 13 can be moved to an exposure position close to the photoconductor drum 11 in conjunction with the opening / closing operation of the front cover 101 and a retracted position shown by a broken line in FIG. 2 separated from the peripheral surface of the photoconductor drum 11. It has become. As the exposure apparatus 13, one that deflects and scans the laser beam configured according to the image information along the axial direction of the photoconductor drum 11 may be used. When an exposure device 13 that deflects and scans the laser beam is used, it is not necessary to retract the exposure device 13 because it can be exposed from a position away from the peripheral surface of the photoconductor drum 11.

As shown in FIG. 3, the developing apparatus 14 holds the developing agent 4 inside the housing 140 in which the opening and the accommodating chamber of the developing agent 4 are formed, and conveys the developing agent 4 to the developing region facing the photoconductor drum 11. It is held by the developing roll 141 as an example of the developing agent holding means, the stirring and conveying members 142 and 143 such as two screw augers that convey the developing agent 4 so as to pass through the developing roll 141, and the developing roll 141. It is configured by arranging a layer thickness regulating member 144 or the like that regulates the amount (layer thickness) of the developing agent. A development bias voltage is supplied to the developing device 14 from a power supply device (not shown) between the developing roll 141 and the photoconductor drum 11. Further, as will be described later, the developing roll 141 and the stirring and transporting members 142 and 143 rotate in a required direction when power is transmitted from the driving device. Further, as the developer 4, a two-component developer containing a non-magnetic toner and a magnetic carrier is used.

As shown in FIG. 2, the transfer device 15 is a contact-type transfer equipped with a transfer roll that contacts and rotates around the photoconductor drum 11 via a recording sheet 5 and is supplied with a transfer voltage at the time of image formation. It is a device. As the transfer voltage, a DC voltage indicating a polarity opposite to the charging polarity of the toner is supplied from a power supply device (not shown).

As shown in FIG. 3, the drum cleaning device 16 is arranged so as to come into contact with the container-shaped main body 160, which is partially opened, and the peripheral surface of the photoconductor drum 11 after the primary transfer at a required pressure, and remains. It is composed of a cleaning plate 161 that removes and cleans the deposits such as toner, and a delivery member 162 such as a screw auger that collects the deposits such as toner removed by the cleaning plate 161 and transports them to a collection container (not shown). ing. As the cleaning plate 161, a plate-shaped member (for example, a blade) made of a material such as rubber is used.

As shown in FIG. 2, the fixing device 40 rotates in the direction indicated by the arrow and the surface temperature is maintained at a predetermined temperature inside the device housing 43 in which the introduction port and the discharge port of the recording paper 5 are formed. A roll-shaped or belt-shaped heating rotating body 41 heated by a heating means and a belt-shaped or roll-shaped rotating body 41 that rotates in contact with each other at a predetermined pressure in a state substantially along the axial direction of the heating rotating body 41. It is configured by arranging a rotating body 42 for pressurization and the like. In the fixing device 40, the contact portion where the heating rotating body 41 and the pressurizing rotating body 42 come into contact becomes a fixing processing portion (nip portion) N that performs the required fixing treatment (heating and pressurization).

The paper feeding device 20 is arranged so as to exist at a position on the lower side of the image forming device 10 along the vertical direction Y. The paper feeding device 20 accommodates a single (or a plurality of) paper accommodating bodies 22 in which recording paper 5 of a desired size, type, etc. is loaded on the loading plate 21, and recording paper 5 from the paper accommodating body 22. It is mainly composed of a sending device 23 that sends out one sheet at a time. The paper feeding device 20 can be attached to and detached from the apparatus main body 1a of the image forming apparatus 1 by manually grasping and pulling out the grip portion 24 provided on the front surface of the paper accommodating body 22.

Examples of the recording paper 5 include thin paper such as plain paper and tracing paper used in electrophotographic copying machines and printers, and OHP sheets. In order to further improve the smoothness of the image surface after fixing, it is preferable that the surface of the recording paper 5 is as smooth as possible. For example, coated paper in which the surface of plain paper is coated with resin or the like, art paper for printing, or the like. So-called thick paper having a relatively large basis weight can also be preferably used.

As shown in FIG. 2, between the paper feed device 20 and the transfer device 15, a plurality of (or a single) paper transfer roll pairs 31a, which transport the recording paper 5 fed from the paper feed device 20 to the transfer position, The paper feed transfer path 32 composed of 31b and a transfer guide (not shown) faces upward along the vertical direction Y in front of the device body 1a, and is curved in the X direction from the middle of the device body 1a. It is provided. The paper transport roll pair 31b arranged at a position immediately before the transfer position in the paper feed transport path 32 is configured as, for example, a roll (resist roll) for adjusting the transport timing of the recording paper 5. Further, from the transfer device 15 to the fixing device 40, a paper transport path 33 is provided along the horizontal direction X in order to transport the recording paper 5 after transfer sent from the transfer device 15 to the fixing device 40.

Further, on the diagonally upper portion of the fixing device 40, one of the two sets of transport rolls 34 and 35 in which one transport roll is commonly configured is transported to the paper ejection unit 36 via one of the transport roll pairs 34. A discharge transport path 37 is provided for discharging the paper. The paper ejection unit 36 is provided in an inclined state on the upper end surface of the apparatus main body 1a.

At the outlet 37a of the discharge transport path 37, a discharge roll pair 37b for discharging the recording paper 5 and inverting the front and back sides is arranged. The rotation direction of the discharge roll pair 37b can be switched between the normal rotation direction and the reverse rotation direction.

Further, in front of the discharge roll vs. 37b, a switching gate (not shown) for switching the transport direction of the recording paper 5 is provided. When an image is formed on both sides of the recording paper 5, the transport direction of the recording paper 5 is switched from the discharge transport path 37 to the double-sided transport path 38 by a switching gate (not shown). At this time, the rotation direction of the discharge roll pair 37b is switched from the normal rotation direction (discharge direction) to the reverse direction after the rear end of the recording paper 5 conveyed in the discharge direction passes through a switching gate (not shown). The recording sheet 5 conveyed in the reverse direction by the discharge roll pair 37b has its transfer path switched in the vertical direction by a switching gate (not shown), and is carried along the back surface of the device main body 1a of the image forming apparatus 1 via the transfer roll pair 35. It is transported from the vertical direction Y to the double-sided transport path 38 formed by being curved along the horizontal direction X. The double-sided transport path 38 includes paper transport rolls 39a and 39b for transporting the recording paper 5 to the paper transport rolls 31b with the front and back reversed, a transport guide (not shown), and the like.

As shown in FIG. 3, a toner cartridge 145 as an example of a developer storage container containing a developer containing at least toner to be supplied to the developing device 14 is arranged above the developing device 14. Below the toner cartridge 145, a toner supply device 147 provided with a supply roll 146 that supplies the toner contained in the toner cartridge 145 to the developing device 14 is provided. Inside the toner cartridge 145, a stirring and transporting member such as an agitator (not shown) that transports the toner contained in the toner cartridge 145 to the toner supply device 147 while stirring is rotatably arranged. The developing device 14, the agitator and the toner supply device 147 (not shown) of the toner cartridge 145 are driven by transmitting power from the driving device, as will be described later.

Further, reference numeral 200 in FIG. 2 indicates a control device that comprehensively controls the operation of the image forming apparatus 1. The control device 200 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory) (not shown), a bus for connecting the CPU, the ROM, and the like, a communication interface, and the like.

<Process cartridge>
In this embodiment, the image forming apparatus 10 excluding the exposure apparatus 13 and the transfer apparatus 15 constitutes a process cartridge 300 as an example of an image forming unit that can be attached to and detached from the apparatus main body 1a of the image forming apparatus 1. There is. As shown in FIGS. 3 and 4, the process cartridge 300 includes a cartridge body 301 in which a photoconductor drum 11, a charging device 12, a developing device 14, a toner cartridge 145, and a cleaning device 16 are integrally mounted. It has. On one side of the cartridge body 301, a concave accommodating portion 302 for accommodating the toner cartridge 145 independently and detachably is provided. Further, as shown in FIG. 4, a photoconductor connecting member 74 and a developing device connecting member 75 as an example of a second drive transmitting means for transmitting power from a driving device, which will be described later, are formed on one side surface of the cartridge body 301. The toner supply connecting member 76 is provided so as to project laterally.

As shown in FIGS. 2 and 5, the apparatus main body 1a of the image forming apparatus 1 is for attaching / detaching the process cartridge 300 and the toner cartridge 145 to / from the operation surface (front surface) side on which the user operates the image forming apparatus 1. It has an opening 105. The opening 105 is opened and closed by the front cover 101. The front cover 101 is attached to the apparatus main body 1a around the rotation shaft 106 arranged at the lower end thereof so as to be openable and closable along the directions of arrows B1 and B2 in the drawing. With the front cover 101 open, the apparatus main body 1a is released from the transmission of the rotational driving force of the apparatus main body 1a to the process cartridge 300 from the drive device described later, and the process cartridge 300 and the toner cartridge 145 can be attached and detached, respectively. .. At the upper end of the front portion 101a of the front cover 101, a contact acting arm 17 for transmitting the opening / closing operation of the front cover 101 to a drive device (not shown) is provided so as to project inward.

In this embodiment, the fixing device 40 is detachably attached to the device main body 1a separately from the process cartridge 300. The attachment / detachment operation of the fixing device 40 is performed by opening / closing a rear cover (not shown).

<Basic operation of image forming apparatus>
Hereinafter, the basic image forming operation by the image forming apparatus 1 will be described.

The image forming apparatus 1 is controlled by the control device 200, and receives command information of a monochrome image forming operation (printing) request from an operation panel (not shown) mounted on the apparatus main body 1a, a user interface (not shown), a printer driver, or the like. Then, the image drawing device 10, the paper feeding device 20, the transport device 30, the fixing device 40, and the like are started.

Then, in the image forming apparatus 10, as shown in FIG. 2, the photoconductor drum 11 first rotates in the direction indicated by the arrow A, and the charging device 12 makes the surface of the photoconductor drum 11 have a required polarity (embodiment). 1 has a negative polarity) and the potential is charged. Subsequently, the exposure apparatus 13 irradiates the surface of the photoconductor drum 11 after charging with light emitted based on the information of the image input to the image forming apparatus 1, and the surface thereof is configured with a required potential difference. Form an electrostatic latent image.

Subsequently, the developing device 14 electrostatically supplies black toner charged with a required polarity (minus polarity) from the developing roll 141 to the electrostatic latent image formed on the photoconductor drum 11. Adhere and develop. By this development, the electrostatic latent image formed on the photoconductor drum 11 is visualized as a toner image developed with black toner. Toner is supplied from the toner cartridge 145 to the developing device 14 of the process cartridge 300 via the toner supply device 147 at a required timing.

Subsequently, when the toner image formed on the photoconductor drum 11 is conveyed to the transfer position, the transfer device 15 transfers the toner image to the recording paper 5.

Further, in the image forming apparatus 10 in which the transfer is completed, the drum cleaning apparatus 16 scrapes off the deposits and cleans the surface of the photoconductor drum 11. As a result, the image forming apparatus 10 is put into a state in which the next image forming operation can be performed.

The paper feed device 20 feeds the required recording paper 5 to the paper feed transfer path 32 in accordance with the image drawing operation. In the paper feed transport path 32, the paper transport roll pair 31b as a resist roll feeds and supplies the recording paper 5 to the transfer position in accordance with the transfer timing.

Subsequently, the recording paper 5 on which the toner image is transferred is transported to the fixing device 40 via the paper transport path 33. In the fixing device 40, the necessary fixing treatment (heating and addition) is performed by introducing the transferred recording paper 5 into the fixing processing unit N between the rotating rotating body 41 for heating and the rotating body 42 for pressurization. Pressure) is applied to fix the unfixed toner image on the recording paper 5. The recording paper 5 after the fixing is completed is provided at the upper end of the apparatus main body 1a by the discharge roll pair 37b along the discharge transport path 37 during the image forming operation of only forming an image on one side thereof. It is discharged to the paper ejection unit 36.

When an image is formed on both sides of the recording paper 5, the recording paper 5 having an image formed on one side is conveyed to the discharge roll pair 37b by a switching gate (not shown), and the recording paper 5 is once separated by the discharge roll pair 37b. It is transported in the discharge direction. After that, the rotation direction of the discharge roll vs. 37b is reversed while the discharge roll vs. 37b is holding the rear end of the recording paper 5, the front and back sides of the recording paper 5 are reversed, and then again via the double-sided transport path 38. The toner image is transferred to the transfer device 15 and the toner image is transferred to the back surface of the recording paper 5. The recording paper 5 on which the toner image is transferred on the back surface is conveyed to the fixing device 40 via the paper transport path 33, subjected to fixing treatment (heating and pressurization) by the fixing device 40, and the paper is discharged by the discharge roll pair 37b. It is discharged to the unit 36.

By the above operation, the recording paper 5 on which the monochrome image is formed is output.

By the way, in the image forming apparatus 1, when the toner contained in the toner cartridge 145 is consumed by the image forming operation and the toner cartridge 145 becomes empty or nearly empty, the toner cartridge 145 is new. Replaced with toner cartridge 145. Further, in the image forming apparatus 1, when the photoconductor drum 11 or the like of the process cartridge 300 is worn due to the image forming operation and the photoconductor drum 11 has reached the end of its life, the process cartridge 300 is replaced with a new one. To.

The process cartridge 300 and the toner cartridge 145 are replaced with the front cover 101 of the image forming apparatus 1 open. Therefore, the drive device that drives the process cartridge 300 and the toner cartridge 145 is configured to release (block) the transmission of the rotational driving force in conjunction with the opening / closing operation of the front cover 101.

<Structure of drive transmission mechanism and drive device>
FIG. 6 shows a configuration diagram of a drive device to which the drive transmission mechanism according to the first embodiment is applied.

As shown in FIG. 1, the drive device 50 is mounted inside one side surface 104 (right side surface in the illustrated example) of the device main body 1a of the image forming device 1. As shown in FIG. 6, the drive device 50 includes a device board 51 arranged on one side surface of the device body 1a in an upright state along the vertical direction Y. The device substrate 51 is formed in the shape of a flat plate having a substantially rectangular front surface in which the upper left corner is cut out. A drive motor 52 as an example of a drive source is attached to the device board 51 on one side (left side in the illustrated example) of the lower end portion thereof. The drive motor 52 is rotationally driven at a required speed by a drive circuit (not shown) mounted on the drive board 52a based on the control operation of the control device 200. The drive motor 52 rotationally drives the image forming means such as the photoconductor drum 11 of the image forming apparatus 1, the developing apparatus 14, the toner cartridge 145, the paper feeding device 20, the conveying device 30, and the fixing device 40.

A drive gear 53 made of a Hasba gear or the like is integrally formed on the rotating shaft of the drive motor 52. The drive gear 53 of the drive motor 52 includes a first transmission gear 54 that transmits a rotational driving force only to the photoconductor drum 11 of the process cartridge 300, a developing device 14 and a toner cartridge 145 of the process cartridge 300, and a device main body 1a. The second transmission gear 55 that transmits the rotational driving force is meshed with the paper feed device 20 and the transfer device 30 of the above. The first and second transmission gears 54 and 55 are composed of two hasba gears having the same outer diameter, which are coaxially and independently rotatably arranged at different positions in the axial direction. In the illustrated example, the first transmission gear 54 is arranged on the back surface side of the second transmission gear 55 along the axial direction. Further, the drive gear 53 of the drive motor 52 is meshed with a third transmission gear 56 that transmits a rotational driving force to the fixing device 40 of the device main body 1a.

The apparatus substrate 51 has a photoconductor drive gear as an example of a drive means for rotationally driving the photoconductor drum 11 at a position corresponding to one end of the photoconductor drum 11 mounted on the process cartridge 300 along the axial direction. 57 is arranged. The photoconductor drive gear 57 is directly meshed with the first transmission gear 54 to transmit the rotational driving force. The photoconductor drum 11 is a member having a relatively large outer diameter among image forming means. When the process speed of the image forming apparatus 1 is constant, the rotation speed of the photoconductor drive gear 57 that rotationally drives the photoconductor drum 11 having a relatively large outer diameter becomes slow. Therefore, the photoconductor drive gear 57 has a larger outer diameter than the other transmission gears 54, 55 and the like.

As shown in FIG. 7, one side surface (inner side surface of the apparatus main body 1a) of the photoconductor drive gear 57 is located at one end of the developing roll 141 of the developing apparatus 14 mounted on the process cartridge 300 along the axial direction. A developing device driving gear 58 as an example of a driving means for rotationally driving the developing roll 141 or the like is arranged at a corresponding position. As shown in FIG. 6, rotational driving force is transmitted from the second transmission gear 55 to the developing device drive gear 58 via a plurality of intermediate gears 59, 60 and the like. As described above, the photoconductor drive gear 57 has a larger outer diameter than the other transmission gears 54, 55 and the like. Further, the distance between the axes of the photoconductor drive gear 57 and the developing device drive gear 58 is uniformly determined by the outer diameters of the photoconductor drum 11 and the developing roll 141. Therefore, in the illustrated embodiment, the photoconductor drive gear 57 and the developing device drive gear 58 are not arranged on the same plane, and the developing device drive gear 58 is located on one side surface of the photoconductor drive gear 57. There is. The developing device drive gear 58 is arranged on the same plane (meshing surface) as the second transmission gear 55 and the plurality of intermediate gears 59 and 60 arranged on the front side (front side in the drawing) along the axial direction. ..

The photoconductor drive gear 57 and the developer drive gear 58 are arranged in a state in which two rotation axes C1 and C2, which are the centers of rotation, are adjacent to each other at a distance corresponding to the distance between the photoconductor drum 11 and the development roll 141. ing. Here, the rotation shafts C1 and C2 of the photoconductor drive gear 57 and the developer drive gear 58 mean the rotation centers of the photoconductor drive gear 57 and the developer drive gear 58, and mean the rotation shaft as a member. is not.

Further, as shown in FIG. 6, the apparatus substrate 51 has an agitator of the toner cartridge 145 at a position corresponding to one end of the toner cartridge 145 along the axial direction of the agitator (not shown) in the center of the upper portion thereof. A toner supply drive gear 61 is arranged as an example of a drive means for rotationally driving (not shown). A rotational driving force is transmitted from the second transmission gear 55 to the toner supply drive gear 61 via a plurality of intermediate gears 59, 60, 62 and the like that are partially common to the developing device 14.

Further, on the device substrate 51, the heating rotating body 41 of the fixing device 40 is rotationally driven at a position corresponding to one end portion along the axial direction of the heating rotating body 41 of the fixing device 40 at the left end portion thereof. A fixing device drive gear 63 is arranged as an example of the drive means. Rotational driving force is transmitted to the fixing device drive gear 63 from the drive gear 53 of the drive motor 52 via the third transmission gear 56 and the intermediate gear 64.

Further, the feeding device 20 and the conveying device 30 arranged in the apparatus main body 1a of the image forming apparatus 1 have a plurality of devices that are partially common to the drive gear 53 to the second transmission gear 55 of the drive motor 52, the developing device 14, and the like. The rotational driving force is transmitted via the intermediate gears (including the driving gears that drive the feeding device 20 and the conveying device 30) 59, 60, 62, 651 to 658 and the like.

By the way, as shown in FIG. 5, the photoconductor drum 11, the developing device 14, and the toner cartridge 145 of the process cartridge 300 attached to and detached from the apparatus main body 1a of the image forming apparatus 1 have the process cartridge 300 and the toner cartridge 145. By mounting the .. The drive transmission mechanism 70 drives the photoconductor drive gear 57 and the developing device in conjunction with the opening / closing operation of the front cover 101 of the image forming apparatus 1 which is opened / closed when the process cartridge 300 and the toner cartridge 145 are attached / detached to / from the apparatus main body 1a. It is configured to switch between a state in which the rotational driving force is transmitted from the gear 58 and the toner supply driving gear 61 and a state in which the transmission of the rotational driving force is released (blocked).

As shown in FIG. 7, the drive transmission mechanism 70 is provided along the axial directions (same direction) of a plurality (two) of adjacent rotating shafts C1 and C2 of the photoconductor drive gear 57 and the developing device drive gear 58, respectively. A photoconductor main coupling 71 and a developing device main coupling 72 are provided as an example of a plurality of first drive transmission means that are movably arranged. Further, the drive transmission mechanism 70 includes a fixing device main coupling 73 as an example of the first drive transmission means that is movably arranged along the axial direction of the fixing device drive gear 63.

As shown in FIG. 8, the photoconductor drive gear 57 integrally has a shaft core portion 571 formed in a cylindrical shape protruding toward one side surface at the center thereof. A photoconductor main coupling 71 is movably mounted on the shaft core portion 571 along the direction of the rotation shaft C1 on one side surface of the photoconductor drive gear 57. As shown in FIG. 9, the photoconductor main coupling 71 has a cylindrical first gear portion 711 in which a spur gear made of an involut gear is formed on the outer periphery thereof, and the first gear portion 711 at the tip of the first gear portion 711. It integrally has a cylindrical second gear portion 712 in which the outer diameter is set smaller than that of the portion 711 and a spur gear made of an involut gear is formed on the outer circumference. A tapered portion 712a is provided at the tip of the second gear portion 712. The photoconductor main coupling 71 includes a first contact portion 713 that projects radially outward between the first gear portion 711 and the second gear portion 712.

The shaft core portion 571 of the photoconductor drive gear 57 is formed with an internal gear 572 made of a spur gear, which is an involute gear that meshes with the first gear portion 711 of the photoconductor main coupling 71. The photoconductor main coupling 71 is configured to be movable along the axial direction in a state where the first gear portion 711 is meshed with the internal gear 572 of the photoconductor drive gear 57 and the rotational driving force is transmitted. Further, as shown in FIGS. 4 and 16, the second gear portion 712 of the photoconductor main coupling 71 is provided at one end of the photoconductor drum 11 of the process cartridge 300 along the axial direction. It is configured to be meshable (coupling) and separable with the photoconductor-subordinate coupling 74 as an example of the transmission means. The photoconductor slave coupling 74 is formed in a cylindrical shape having an internal gear 741 formed of a spur gear which is an involute gear that meshes with the second gear portion 712 of the photoconductor main coupling 71 on its inner peripheral surface. At the open end of the internal gear 741, a tapered portion 741a whose diameter is increased toward the end is provided. The photoconductor slave coupling 74 is attached in a state of being fixed to one end of the photoconductor drum 11 along the axial direction. On the side surface of the process cartridge 300, a cylindrical protective member 303 that protects the photoconductor-slave coupling 74 is provided on the outer periphery of the photoconductor-slave coupling 74 so as to project laterally.

The photoconductor main coupling 71 is not limited to the one provided with the first and second gear portions 711 and 712 made of involute gears, but is rotationally driven via the photoconductor main coupling 71. Since the photoconductor drum 11 is a member that directly affects the image quality, it is desirable that the speed fluctuation and the like are small and the rotation accuracy is high. The photoconductor main coupling 71 including the first and second gear portions 711 and 712 made of involute gears is suitable because it is possible to transmit the rotational driving force to the photoconductor drum 11 with relatively high rotational accuracy. Used for.

As shown in FIG. 8, the photoconductor main coupling 71 is a first urging means interposed between the inner end surface of the shaft core portion 571 of the photoconductor drive gear 57 and the inner end surface of the first gear portion 711. As an example, the first coil spring 714 is urged in a protruding direction. The amount of protrusion of the photoconductor main coupling 71 along the axial direction of the photoconductor drive gear 57 is regulated by a fixed shaft 715 mounted on the shaft core portion 571 of the photoconductor drive gear 57.

Further, as shown in FIG. 8, the developing device main coupling 72 is mounted on the developing device driving gear 58 so as to be displaceable along the axial direction of the rotating shaft C2. As shown in FIGS. 10 and 11, the developing device drive gear 58 is integrally provided with a substantially cylindrical or cylindrical drive transmission shaft 581 provided on one side surface thereof so as to project along the axial direction. There is. A plurality of (three in the illustrated example) first convex portions 582 having a substantially semicircular cross section are integrally provided on the outer periphery of the drive transmission shaft 581 along the circumferential direction. Further, the three first convex portions 582 are arranged at positions that form an angle of 120 degrees with each other on the outer circumference of the drive transmission shaft 581. Each first convex portion 582 is formed over the entire length along the axial direction of the drive transmission shaft 581. The developing device drive gear 58 is provided with a first shaft support portion 583 formed in a cylindrical shape on the outer circumference of the drive transmission shaft 581. Further, the developing device drive gear 58 is provided with a second shaft support 585 formed in a cylindrical shape having a diameter smaller than that of the first shaft support 583 on the side surface opposite to the drive transmission shaft 581. The first shaft branch 583 is set to have a length (thickness) similar to the length (thickness) of the developing device drive gear 58 along the axial direction.

The developing apparatus main coupling 72 is formed in a substantially cylindrical shape. The developing device main coupling 72 has a mounting hole 721 in which a plurality of first concave portions 722 that are engaged with a plurality of first convex portions 582 of the drive transmission shaft 581 are formed on the inner peripheral surface thereof. The developing apparatus main coupling 72 integrally includes a second contact portion 723 that protrudes outward in the radial direction in an annular shape at the base end portion thereof. A plurality of (three in the illustrated example) substantially hemispherical second convex portions 724 are integrally provided at the tip of the developing apparatus main coupling 72 so as to project laterally along the circumferential direction. Each second convex portion 724 is arranged at the same position as the first convex portion 582 along the circumferential direction of the developing apparatus main coupling 72.

By the way, in this embodiment, the developing device main coupling 72 is configured to allow tilting relative to the drive transmission shaft 581 of the developing device drive gear 58.

That is, the outer diameter including the first convex portion 582 of the drive transmission shaft 581 of the developing device drive gear 58 and the inner diameter including the first concave portion 722 of the developing device main coupling 72 are the drive transmission shaft 581 of the developing device drive gear 58. The developing device main coupling 72 is set to have a required inner / outer diameter difference that allows movement along the axial direction C2. In this case, the developing device main coupling 72 can move along the axial direction C2 according to the required inner / outer diameter difference with respect to the drive transmission shaft 581 of the developing device driving gear 58. However, when the developing device main coupling 72 tries to incline with respect to the drive transmission shaft 581 of the developing device drive gear 58, the tip of the drive transmission shaft 581 comes into contact with the mounting hole 721 of the developing device main coupling 72, and at the same time, The base end of the drive transmission shaft 581 of the developing device drive gear 58 comes into contact with the mounting hole 721 of the developing device main coupling 72. Therefore, the developing device main coupling 72 can be slightly inclined with respect to the drive transmission shaft 581 of the developing device driving gear 58, depending on the required difference in inner and outer diameters, and a substantial inclination is not allowed. ..

In this embodiment, as shown in FIGS. 12 and 14, at the tip of the drive transmission shaft 581 of the developing device drive gear 58, a corner portion is cut out in a rounded shape over the entire circumference of the developing device main coupling 72. A first gap forming portion 584 is provided to form a gap that allows inclination with respect to the inner peripheral surface of the mounting hole 721. Similarly, at the base end of the mounting hole 721 of the developing device main coupling 72, the outer periphery of the drive transmission shaft 581 of the developing device driving gear 58 is cut out in a tapered shape over the entire circumference including the first recess 722 of the mounting hole 721. A second gap forming portion 726 is provided to form a gap that allows inclination with respect to the surface.

Further, even when the first and second gap forming portions 584 and 726 are formed in the mounting holes 721 of the drive transmission shaft 581 of the developing device drive gear 58 and the developing device main coupling 72, the developing device main coupling 72 Is mounted relatively long with respect to the drive transmission shaft 581 of the developing device drive gear 58, even if the developing device main coupling 72 tries to incline with respect to the drive transmission shaft 581 of the developing device drive gear 58. The outer periphery of the first gap forming portion 584 of the drive transmission shaft 581 of the developing device drive gear 58 comes into contact with the mounting hole 721 of the developing device main coupling 72, and the outer peripheral surface of the drive transmission shaft 581 of the developing device drive gear 58 is formed. It comes into contact with the inner peripheral end of the second gap forming portion 726 of the mounting hole 721 of the main coupling 72 of the developing apparatus, and the required inclination is limited.

Now, as shown in FIG. 13, the cross-sectional shape of the drive transmission shaft 581 of the developing device drive gear 58 and the mounting hole 721 of the developing device main coupling 72 is approximated by a circular shape, and the drive transmission shaft of the developing device drive gear 58 is approximated. The outer diameter of 581 is D1, the inner diameter of the mounting hole 721 of the developing device main coupling 72 is D2, the insertion length of the drive transmission shaft 581 of the developing device drive gear 58 inserted into the developing device main coupling 72 is L, and the developing device. Assuming that the inclination angle of the drive transmission shaft 581 of the drive gear 58 is θ, the following relational expression holds.
D2 = D1cosθ + Lsinθ ... (1)

In FIG. 13, even when the outer diameter D1 of the drive transmission shaft 581 of the developing device drive gear 58 is constant, the first gap forming portion 584 is provided at the tip of the drive transmission shaft 581 of the developing device drive gear 58. Corresponds to a decrease in the outer diameter D1 of the drive transmission shaft 581. Further, even when the inner diameter D2 of the mounting hole 721 of the developing device main coupling 72 is constant, it is possible to provide the second gap forming portion 726 at the base end of the mounting hole 721 of the developing device main coupling 72. This corresponds to expanding the inner diameter D2 of the mounting hole 721. Therefore, the outer diameter including the first convex portion 582 of the drive transmission shaft 581 of the developing device drive gear 58 and the inner diameter including the first concave portion 722 of the developing device main coupling 72 are set to the drive transmission shaft 581 of the developing device drive gear 58. Even when the required inner / outer diameter difference is set to allow the movement of the developing device main coupling 72 along the axial direction C2, by providing the first and second gap forming portions 584,726, the developing device driving gear is provided. It is possible to allow the drive transmission shaft 581 of 58 to be tilted. Therefore, the developing device driving gear 58 and the developing device main coupling 72 form a so-called universal joint capable of transmitting the rotational driving force in a state where the rotating shaft is tilted. The difference between the inner and outer diameters of the drive transmission shaft 581 of the developing device drive gear 58 and the mounting hole 721 of the developing device main coupling 72 may be set to a relatively large value so as to increase the inclination of the rotating shaft.

Further, as shown in FIGS. 4 and 16, the plurality of second convex portions 724 of the developing apparatus main coupling 72 are provided at the end portions of the developing roll 141 of the process cartridge 300 along the axial direction. It is configured to be meshable (coupling) and separable with the developing device slave coupling 75 as an example of the drive transmission means. The developing device slave coupling 75 is provided with a plurality of second recesses 751 on its inner peripheral surface that are engaged with a plurality of second convex portions 724 of the developing device coupling 72. As shown in FIG. 8, the developing device main coupling 72 is a second as an example of the second urging means interposed between the end surface of the developing device driving gear 58 and the lower end surface of the second contact portion 723. It is urged in a protruding direction by a 2-coil spring 725. As shown in FIG. 17, the developing apparatus main coupling 72 is rotatably attached in a state where the developing apparatus main coupling 72 is in contact with the developing apparatus slave coupling 75 of the developing roll 141 and the protruding position is restricted. On the side surface of the process cartridge 300, a protective member 304 that protects the developing device secondary coupling 75 is provided on the outer periphery of the developing device secondary coupling 75 in a state of protruding sideways. Of course, the developing apparatus main coupling 72 may be configured to regulate the protruding position by a regulating member (not shown).

As shown in FIG. 15, the developing device drive gear 58 rotatably supports the second shaft support 585 via the bearing member 586 on the housing 501 of the drive device 50 that rotatably supports the photoconductor drive gear 57. Has been done. Further, in the developing device driving gear 58, a first shaft support portion 583 as an example of a sliding portion is rotatably supported by a metal casing 502 as an example of a covering means for covering the developing device driving gear 58 and the like. .. On the casing 502, the support portion 502a that rotatably supports the first shaft support portion 583 of the developing device drive gear 58 is directed inward (toward the first shaft support portion 583 side) so as to come into contact with the outer peripheral surface of the first shaft support portion 583. It is provided in a curved shape. Therefore, the structure that rotatably supports the developing device driving gear 58 is substantially equal to the length along the axial direction of the developing device driving gear 58. In FIG. 15, reference numeral 60a indicates an intermediate gear that is meshed with the developing device driving gear 58 to transmit the rotational driving force.

Further, as shown in FIG. 7, the fixing device main coupling 73 as an example of the first drive transmission means is mounted on the fixing device drive gear 63 so as to be displaceable along the axial direction. As shown in FIG. 18, the fixing device drive gear 63 integrally includes a cylindrical drive transmission shaft 631 provided on one side surface thereof so as to project along the axial direction. A plurality of (four in the illustrated example) third convex portions 632 having a substantially semicircular cross section are integrally provided on the outer periphery of the drive transmission shaft 631 along the circumferential direction. Further, the four third convex portions 632 are arranged at positions that form an angle of 90 degrees with each other on the outer periphery of the drive transmission shaft 631. Each third convex portion 632 is formed over the entire length along the axial direction of the drive transmission shaft 631. The fixing device drive gear 63 is provided with a shaft support portion 633 formed in a cylindrical shape on the outer circumference of the drive transmission shaft 631.

As shown in FIG. 18B, the fixing device main coupling 73 is formed in a substantially double cylindrical shape. The fixing device main coupling 73 has a mounting hole 731 in which a plurality of third recesses 732 that are engaged with a plurality of third convex portions 632 of the drive transmission shaft 631 are formed on the inner peripheral surface thereof. The fixing device main coupling 73 is integrally provided with a third contact portion 733 protruding outward in the radial direction in an annular shape at the base end portion thereof. The third contact portion 733 is provided with an inclined surface 733a that is inclined so as to be lowered toward the outer periphery. A plurality of (six in the illustrated example) engaging portions 734 are integrally provided at the tip of the fixing device main coupling 73 along the circumferential direction thereof. Each engaging portion 734 is formed in a substantially right-angled triangular shape from a plane 734a along the axial direction and an inclined surface 734b inclined from the tip end to the base end of the plane 734a.

Further, as shown in FIG. 18A, the plurality of engaging portions 734 of the fixing device main coupling 73 are rotatable and fixed in position on the device substrate 51 of the drive device 50 via the rotation shaft 791. It is configured to be meshable (coupling) and separable with the fixing device slave coupling 79 as an example of the mounted second drive transmission means. The fixing device slave coupling 79 is composed of a gear having a gear portion 792 on the outer peripheral surface. The fixing device slave coupling 79 has a plurality of (six in the illustrated example) second engagements that are engaged with a plurality of first engagement portions 734 of the fixing device main coupling 73 at one end along the axial direction thereof. It has a joint 793. The plurality of second engaging portions 793 are formed in a shape capable of engaging with the engaging portions 734 of the fixing device main coupling 73. Each engaging portion 793 is formed in a substantially right-angled triangular shape from a plane 793a along the axial direction and an inclined surface 793b inclined from the tip end to the base end of the plane 793a. The direction in which the fixing device main coupling 73 protrudes by a third coil spring 795 as an example of the third urging means interposed between the end surface of the fixing device drive gear 63 and the lower end surface of the third contact portion 733. Is being urged to.

On the other hand, as shown in FIG. 19, the toner supply main coupling 76 as an example of the first drive transmission means is mounted on the toner supply drive gear 61 so as to be displaceable along the axial direction. The toner supply drive gear 61 integrally includes a drive transmission shaft 611 provided on one side surface thereof so as to project along the axial direction. A plurality of (three in the illustrated example) fourth convex portions 612 having a substantially semicircular cross section are integrally provided on the outer periphery of the drive transmission shaft 611 along the circumferential direction. Further, the three third convex portions 612 are arranged at positions at an angle of 120 degrees with each other on the outer circumference of the drive transmission shaft 611. Each fourth convex portion 612 is formed over the entire length along the axial direction of the drive transmission shaft 611.

The toner supplier coupling 76 is formed in a substantially cylindrical shape. The toner supply main coupling 76 has a mounting hole 761 formed on its inner peripheral surface 761 with a plurality of fourth recesses 762 that are engaged with a plurality of fourth convex portions 612 of the drive transmission shaft 611. The toner supply main coupling 76 is integrally provided with a fourth contact portion 763 projecting outward in the radial direction in an annular shape at the base end portion thereof. A plurality of (six in the illustrated example) fifth convex portions 764 having a substantially hemispherical shape are integrally provided at the tip of the toner supply main coupling 76 so as to project laterally along the circumferential direction. As the toner supply main coupling 76, similarly to the photoconductor main coupling 71, one formed in a cylindrical shape including the first and second gear portions may be used.

Further, as shown in FIG. 20, the plurality of fifth convex portions 764 of the toner supply main coupling 76 are provided at the end portions of the toner cartridge 145 along the axial direction of the agitator (not shown). As an example, it is configured to be meshable (coupling) and separable with the toner supply slave coupling 77. The toner supply slave coupling 77 includes a plurality of fifth recesses 771 that are engaged with a plurality of fifth protrusions 764 of the toner supply main coupling 76 along its circumferential direction. As shown in FIG. 19, the toner supply main coupling 76 is a second as an example of the fourth urging means interposed between the end surface of the toner supply drive gear 61 and the lower end surface of the fourth contact portion 763. It is urged in a protruding direction by a 4-coil spring 764.

<Coupling retract member (switching means)>
As shown in FIG. 6, the drive transmission mechanism 70 is an example of a switching means capable of being displaced (moved) along the axial direction while maintaining a position along the direction intersecting the axial direction with respect to the device substrate 51. The coupling retracting member 80 is provided. The coupling retracting member 80 displaces (moves) the photoconductor main coupling 71 and the developer main coupling 72 along the axial directions of the rotation shafts C1 and C2, whereby the photoconductor-subordinate coupling 74 of the process cartridge 300 is used. And the transmission and release of the rotational driving force to the developing device slave coupling 75 is switched.

Further, the drive transmission mechanism 70 is arranged so as to maintain a position along the direction intersecting the axial direction with respect to the device substrate 51, and displaces (moves) the fixing device main coupling 73 along the axial direction. The rotation cam 85 is provided as an example of the switching means for switching the transmission and release of the rotation driving force to the fixing device slave coupling 79 of the apparatus main body 1a. As will be described later, the rotary cam 85 also has a function of assisting the movement of the coupling retracting member 80 along the axial direction.

As shown in FIG. 7, the coupling retracting member 80 is formed as a plate-shaped member having a substantially parallelogram on the front surface. The coupling retracting member 80 has an upper end surface 801 and a lower end surface 802 arranged in a state of being bent toward the back surface side along the upper end edge and the lower end edge, respectively, and an upper end surface 801 at the left end portion of the upper end surface 801 and the lower end surface 802. The left side surface 803 is provided so that the left end portion is inclined so as to form an obtuse angle, and the right end surface 804 is provided on the right end portions of the upper end surface 801 and the lower end surface 802 so as to be inclined along the same direction at an angle larger than that of the left side surface 803. It has. The coupling retracting member 80 is opened so that the right end portion and the right side surface 804 of the lower end surface 802 are all opened to avoid interference with the casing 502 that rotatably supports the developing device drive gear 58 and the like. As shown in FIG. 6, the coupling retracting member 80 is provided only along the direction (axial direction) intersecting the surface of the device board 51 via the plurality of guide members 81, 82 erected on the device board 51. It is mounted so that it can be moved. The guide members 81 and 82 are arranged at positions corresponding to the left end portion of the upper end surface 801 of the coupling retracting member 80 and the left end portion of the lower end surface 802.

As shown in FIG. 7, there are two circular insertion holes in the substantially central portion of the coupling retracting member 80 into which the second gear portion 712 of the photoconductor main coupling 71 and the developing device main coupling 72 are inserted. 805 and 806 are opened adjacent to each other with a distance equal to the distance between the rotation shafts C1 and C2 of the photoconductor drive gear 57 and the developing device drive gear 58. As shown in FIG. 8, the inner diameters of the two insertion holes 805 and 806 are larger than the outer diameters of the second gear portion 712 of the photoconductor main coupling 71 and the developing device main coupling 72, and the photoconductor main coupling It is set to be smaller than the outer diameter of the first and second contact portions 713 and 723 of the 71 and the developing apparatus main coupling 72. The inner peripheral surface of one of the insertion holes 806 is provided with a plurality of relief portions 807 through which the plurality of convex portions 724 of the developing apparatus main coupling 72 are inserted. Further, the two insertion holes 805 and 806 are in contact with the first and second contact portions 713 and 723 of the photoconductor main coupling 71 and the developing device main coupling 72, and the photoconductor main coupling 71 and the developing device are in contact with each other. By making the timing of pushing down the main coupling 72 different, the operating force when moving the coupling retracting member 80 is reduced.

Further, as shown in FIG. 8, the two insertion holes 805 and 806 of the coupling retracting member 80 are formed so that the positions of the lower end surfaces 805a and 806a along the axial direction are different. In the illustrated embodiment, the distance G1 between the lower end surface 805a along the axial direction of one insertion hole 805 and the first contact portion 713 of the photoconductor main coupling 71 is in the axial direction of the other insertion hole 806. The distance between the lower end surface 806a along the line and the second contact portion 733 of the main coupling 72 of the developing device is set to be smaller than G2 (G1 <G2). Note that FIG. 8 shows a state in which the coupling retracting member 80 is moved to the drive position, and the photoconductor main coupling 71 and the developing device main coupling 72 are coupled to the photoconductor slave coupling 74 and the developing device slave coupling 75. Is shown. When the coupling retracting member 80 moves downward in FIG. 8, the lower end surface 805a of the insertion hole 805 of the coupling retracting member 80 first contacts the first contact portion 713 of the photoconductor main coupling 71. After that, the lower end surface 806a of the insertion hole 806 of the coupling retracting member 80 comes into contact with the second contact portion 723 of the developing apparatus main coupling 72.

As shown in FIG. 7, the upper end surface 801 of the coupling retracting member 80 is provided with a first pressing portion 808 projecting laterally (upwardly) in a substantially cylindrical shape at the right end portion thereof. Further, the upper end surface 801 of the coupling retracting member 80 is provided with a first push upper portion 809 protruding in a semi-cylindrical shape toward the side (upward) at a distance of a required distance on the left side of the first push portion 808. There is. The first push upper portion 809 is located on the surface side of the upper end surface 801 from the first push portion 808.

Further, the lower end surface 802 of the coupling retracting member 80 is provided with a second pressing portion 810 protruding laterally (downwardly) in a substantially cylindrical shape at the central portion thereof. The second pressing portion 810 is formed longer than the first pressing portion 808. The lower end surface 802 of the coupling retracting member 80 is provided with a second push upper portion 811 protruding downward in a semi-cylindrical shape at a distance of a required distance on the left side of the second push portion 810. The second push upper portion 811 is located on the surface side of the lower end surface 802 from the second push portion 810.

As shown in FIGS. 7 and 8, the left side surface 803 of the coupling retracting member 80 is provided with a step portion 812 formed along the left side surface 803 and one step lower than the surface of the coupling retracting member 80. ..

As shown in FIG. 7, the rotary cam 85 is rotatably arranged between the coupling retracting member 80 and the fixing device main coupling 73. The rotary cam 85 includes a cam body 851 that is supported so as to be rotatable via a shaft support portion 851a and is formed in a disk shape. The cam main body 851 is provided with first and second cam portions 852 and 853 formed in a convex shape curved in one axial direction (downward in the drawing) at the outer peripheral end thereof. The first and second cam portions 852 and 853 are arranged so as to face the outer peripheral end of the cam main body 851 at an angle of about 180 degrees. The first cam portion 852 abuts on the stepped portion 812 of the coupling retracting member 80 and acts to push down the coupling retracting member 80. On the other hand, the second cam portion 853 abuts on the third contact portion 733 of the fixing device main coupling 73 and acts to push down the fixing device main coupling 73. The first and second cam portions 852 and 853 have a height difference along the axial direction between the stepped portion 812 of the coupling retracting member 80 and the third contact portion 733 of the fixing device main coupling 73. The 1 cam portion 852 is arranged so as to project upward from the second cam portion 853 along the axial direction of the cam main body 851. Further, as shown in FIG. 25, the cam main body 851 is provided with a drive shaft 854 for rotationally driving the rotary cam 85 by the link member 90 described later at a position eccentric from the shaft support portion 851a to the link member 90 side. ing. A concave notch 851b is provided on the outer periphery of the cam body 851 in order to avoid interference with the fixing device slave coupling 79 during assembly.

Further, the first and second cam portions 852 and 853 of the rotary cam 85 are configured so that the timing of pushing down the coupling retracting member 80 and the fixing device main coupling 73 is different. More specifically, the first cam portion 852 starts pushing down the coupling retracting member 80 as the rotary cam 85 rotates, and then starts pushing down the fixing device main coupling 73. The protrusion amount of the cam portions 852 and 853 and the protrusion position along the circumferential direction of the cam main body 851 are set respectively.

<Link member (mode of transportation)>
As shown in FIG. 6, the apparatus substrate 51 serves as an example of a moving means for displacementing (moving) the coupling retracting member 80 along the axial direction while maintaining a position along the direction intersecting the axial direction. The link member 90 is attached. The link member 90 has a function of rotating the rotary cam 85. Further, the link member 90 also has a function of moving the toner supply main coupling 76 along the axial direction. The link member 90 is attached so as to be movable in the directions of arrows D1 and D2 along the surface of the device board 51, which is a direction intersecting the axial direction of the device board 51. As shown in FIG. 23, the link member 90 is arranged on substantially the same plane as the coupling retracting member 80.

As shown in FIG. 21, the link member 90 is formed in a laterally substantially Y shape in front of the link member 90. The link member 90 has first and second link portions 901 and 902 arranged on the outside of the upper end surface 801 and the lower end surface 802 of the coupling retracting member 80 in parallel with the upper end surface 801 and the lower end surface 802, respectively. A substantially flat guide portion 903 arranged parallel to the upper end surface 801 of the coupling retracting member 80 on the side (upper side) of the tip portion of the 1 link portion 901, and a right end along the longitudinal direction of the first link portion 901. It is provided with a base end portion 904 arranged linearly in the portion. The second link portion 902 is integrally connected to the base end portion 904 via a connecting portion 905 arranged substantially parallel to the right side surface 804 of the coupling retracting member 80.

The link member 90 is provided with an elongated hole 906 at the tip of the guide member 903. At the tip of the guide member 903, a recess 907 that opens downward in the drawing for rotating the rotary cam 85 is formed. Further, a cylindrical shaft portion 908 is provided at the proximal end of the proximal end portion 904 of the link member 90. Further, the base end portion 904 of the link member 90 is integrally provided with a toner supply evacuation portion 909 for retracting the toner supply main coupling 76 by moving the toner supply main coupling 76 along the axial direction to the side (upper side) of the base end portion 904. There is.

As shown in FIG. 6, the link member 90 inserts a long hole 906 provided at the tip of the guide portion 903 into the cylindrical shaft support portion 91 erected on the apparatus substrate 51, and the second link portion 90. By guiding the lower side surface of the 902 by a guide member 92 erected on the device board 51, the device board 51 is movably attached to the device board 51 along the directions of arrows D1 and D2.

As shown in FIG. 22, the link member 90 has a first inclined surface 910 opened at the tip of the first link portion 901 toward the coupling retracting member 80 side. The first inclined surface 910 is provided in a state of being inclined in a direction intersecting the surface of the device substrate 51 so that the base end portion 904 side of the link member 90 is high and the guide portion 903 side is low. Flat surfaces 911 and 912 are provided at both ends of the first inclined surface 910, respectively. Further, on the surface of the first link portion 901, one first rib 913 is provided so as to be inclined substantially parallel to the first inclined surface 910. The upper end 914 of the first rib 913 is formed flat.

Further, the link member 90 has a second inclined surface 915 opened toward the coupling retracting member 80 side at the tip of the second link portion 902, as shown in FIG. 23 with a partially broken cross section. is doing. The second inclined surface 915 is basically configured in the same manner as the first inclined surface 910, except that the position of the link member 90 along the longitudinal direction is different. The second inclined surface 915 is provided in a state of being inclined in a direction intersecting the surface of the device substrate 51 so that the base end portion 904 side is high and the tip end portion side is low. Flat surfaces 916 and 917 are provided at both ends of the first inclined surface 915, respectively. Further, on the surface of the second link portion 902, three second ribs 918 inclined substantially parallel to the second inclined surface 915 are provided. The upper end 919 of the second rib 918 is formed flat.

As shown in FIG. 24A, when the link member 90 moves in the right direction D2 in the drawing, the first and second inclined surfaces 910 and 915 of the first and second link portions 901 and 902 are coupled. In contact with the first and second pressing portions 808 and 810 of the retracting member 80, the coupling retracting member 80 is placed on the back surface side of the device substrate 51 along the axial direction via the first and second pressing portions 808 and 810. Move downward in FIG. 24). In FIG. 24, for convenience, only the second inclined surface 915 is shown, and the corresponding portions of the first inclined surface 910 are indicated by reference numerals in parentheses. At this time, the first and second pressing portions 808 and 810 of the coupling retracting member 80 are pressed against the flat surfaces 912 and 917 of the link member 90 by the urging force of the first and second coil springs 714 and 725. It is stopped at.

On the other hand, as shown in FIG. 24B, when the link member 90 moves in the left direction D1 in the drawing, the first and second ribs 913 and 918 of the first and second link portions 901 and 902 cup. The coupling retracting member 80 is moved to the surface side along the axial direction via the first and second push-up portions 809, 811 in contact with the first and second push-up portions 809, 811 of the ring retracting member 80. At this time, the first and second pressing portions 809 and 811 of the coupling retracting member 80 are stopped in contact with the flat surfaces 914 and 919 of the link member 90. Further, the first and second push-up portions 808 and 810 of the coupling retracting member 80 are separated from the flat surfaces 911 and 916 of the link member 90.

Further, as shown in FIG. 25, the link member 90 is engaged with the tip of the drive shaft 854 of the rotary cam 85 with the recess 907 provided at the tip of the guide portion 903. Note that FIG. 25 shows a state in which the link member 90 has moved to the end in the direction of arrow D1. At that time, the gap G3 is set to exist between the inner side surface 907a of the recess 907 of the guide portion 903 and the outer peripheral surface of the eccentric shaft 854. In this state, when the link member 90 starts moving in the direction of arrow D2, the inner surface 907a of the recess 907 comes into contact with the drive shaft 854 of the rotary cam 85 and is pushed after moving by a distance corresponding to the gap G3. It moves and starts the operation of rotating the rotary cam 85 along the clockwise direction in the figure. In this way, the rotary cam 85 starts rotating with a timing corresponding to the gap G3 with respect to the movement of the link member 90, and the first cam portion 852 starts pushing down the step portion 812 of the coupling retracting member 80. do. Further, as described above, in the rotary cam 85, after the first cam portion 852 starts pushing down the coupling retracting member 80, the second cam portion 853 pushes down the third contact portion 733 of the fixing device coupling 73. Is configured to start.

Further, the link member 90 includes a toner supply / relief unit 909 as shown in FIGS. 21 and 26. The toner supply retracting unit 909 has a circular shape that communicates with a third inclined surface 920 having a passage through which the toner supply main coupling 76 is inserted and passages provided at both ends of the third inclined surface 920. It is composed of flat surfaces 921 and 922 having an opening. The third inclined surface 920 is inclined in a direction intersecting the surface of the apparatus substrate 51 so that the flat surface 921 on the base end portion 904 side of the link member 90 is high and the flat surface 922 on the guide portion 903 side is low. It is provided in.

As shown in FIG. 26, when the link member 90 moves in the direction of arrow D2 in the drawing, the third contact portion 763 of the toner supply main coupling 76 moves along the third inclined surface 920, and the third It moves to a flat portion 922 provided at one end of the inclined surface 920. Therefore, the toner supply main coupling 76 moves in a direction close to the surface of the device substrate 51 against the urging force of the fourth coil spring 764, and the coupling with the toner supply slave coupling 77 is released.

On the other hand, when the link member 90 moves in the direction of arrow D1 in the drawing, the third contact portion 763 of the toner supply main coupling 76 moves along the third inclined surface 920, and one end portion of the third inclined surface 920. It moves to the flat surface 921 provided in. Therefore, the toner supply main coupling 76 moves in a direction away from the surface of the device substrate 51 by the urging force of the fourth coil spring 764, and is coupled with the toner supply slave coupling 77.

<Movement mechanism of link member>
As shown in FIG. 6, the link member 90 has an arrow E1 over a required rotation angle by opening and closing the front cover 101 via an operating arm 66 connected to a shaft portion 908 provided at the base end portion 904. , Is connected to a rotating body 67 that rotates along the E2 direction.

As shown in FIG. 27A, the apparatus substrate 51 can rotate by contacting the contact acting portion 17 provided on the front cover 101 with the upper end portion on the front side (right side in the drawing). It has a moving body 67. As shown in FIG. 28, the rotating body 67 includes a main body 671 having a cylindrical shaft support portion 671a at its center, an action protrusion 672 projecting laterally from the shaft support portion 671a, and a contact action portion 17. A locking portion 674 is provided at a position facing the contacted portion 673 and the contacted portion 673 to lock an urging means such as a coil spring (not shown). When the rotation position of the rotating body 67 along the circumferential direction exceeds a specific neutral position in the arrow E1 direction, the coil spring (not shown) urges the rotating body 67 in the arrow E1 direction to urge the rotating body 67 in the direction of the arrow E1. When the rotation position along the circumferential direction exceeds a specific neutral position in the direction of arrow E2, the rotating body 67 is locked to the locking portion 674 so as to urge the rotating body 67 in the direction of arrow E2. Further, an end portion of the operating arm 66 is pivotally supported at a position adjacent to the contacted portion 673.

As shown in FIG. 28, the contact acting portion 17 has a plate-shaped main body portion 170 arranged upright at a predetermined position of one end portion on the inner surface of the front cover 101 and diagonally downward toward the tip end side of the main body portion 170. It is composed of a member having a shape having a bent tip portion 171 extending and a recessed portion 172 notched in a shape extending downward at a boundary portion between the main body portion 170 and the bent tip portion 171. Further, the contact action portion 17 is provided with a contact surface portion 173 at the tip of the bending tip portion 171 for contacting and pushing the contacted portion 673 of the rotating body 67 when closing the front cover 101.

Further, the contact action portion 17 is composed of a slope in which the inner wall surface of the recessed portion 172 near the contact surface portion 173 is inclined toward the lower outer side, and when the front cover 101 is opened, the contact action portion 17 and the action protrusion portion 672 of the rotating body 67 are formed. It is formed as a drawer slope portion 174 that comes into contact with each other. Moreover, the inner wall surface of the recessed portion 172 on the opposite side of the contact surface portion 173 is formed of a slope inclined downward and outward, and comes into contact with the action protrusion 672 of the rotating body 67 when the front cover 101 is closed. It is formed as a push-in slope portion 175.

As shown in FIG. 27 (a), when the front cover 101 is rotated in the direction indicated by the arrow B1 and started to be opened, the drawer inclined surface 174 of the contact acting portion 17 on the front cover 101 is exposed to the action collision of the rotating body 67. Upon contact with the portion 672, the rotating body 67 begins to rotate in the direction indicated by the arrow E1. As described above, the rotating body 67 is urged by a coil spring (not shown) and stops in a state of being rotated to a predetermined position in the direction indicated by the arrow E1. As a result, the power due to the rotational movement generated by the rotating body 67 rotating in the direction indicated by the arrow E1 is transmitted to the link member 90 via the acting arm 66. The link member 90 moves in the direction of arrow D2 by a required amount via the action arm 66.

On the other hand, when the front cover 101 is rotated in the direction indicated by the arrow B2 and closed, as shown in FIG. 27 (b), the contact surface portion 173 of the contact action portion 17 on the front cover 101 becomes the action protrusion of the rotating body 67. Upon contact with 672, the rotating body 67 begins to rotate in the direction indicated by the arrow E2. As described above, the rotating body 67 is urged by a coil spring (not shown) and stops in a state of being rotated to a predetermined position in the direction indicated by the arrow E2. As a result, the power due to the rotational movement generated by the rotating body 67 rotating in the direction indicated by the arrow E2 is transmitted to the link member 90 via the acting arm 66. The link member 90 moves in the direction of arrow D1 by a required amount via the action arm 66. In FIG. 27, reference numeral 51a indicates an opening for inserting the contact acting portion 17 opened in the flange portion on the front side of the apparatus substrate 51.

<Operation of drive transmission mechanism and drive device>
In the image forming apparatus 1 according to the first embodiment, the process cartridge 300 and the toner cartridge 145 are operated by the drive transmission mechanism 70 of the drive device 50 in conjunction with the opening / closing operation of the front cover 101 of the device main body 1a as follows. The transmission and release of the rotational driving force to the above can be switched.

That is, in the image forming apparatus 1 according to the first embodiment, as shown in FIG. 5, the front cover 101 moves in the direction of the arrow B1 when the toner cartridge 145 or the process cartridge 300 is newly installed or replaced. It is opened and the opening 105 is opened. In the image forming apparatus 1, when the front cover 101 is opened in the direction of arrow B1, as shown in FIG. 27B, the contact acting portion 17 provided on the front cover 101 is separated from the rotating body 67. evacuate. When the contact acting portion 17 retracts from the rotating body 67, the rotating body 67 rotates by a required angle in the direction of arrow E1 in the drawing due to the urging force of a coil spring (not shown) and stops. The rotational movement of the rotating body 67 is transmitted to the link member 90 via the operating arm 66, and the link member 90 moves by a required amount along the arrow D2 direction and stops.

FIG. 29 shows a drive device 50 in a state in which the link member 90 moves by a required amount along the arrow D2 direction and stops by opening the front cover 101.

As shown in FIG. 29, when the link member 90 moves by a required amount along the arrow D2 direction, the coupling retracting member 80 approaches the surface of the device substrate 51 as the link member 90 moves (the direction ( Displace to the back surface side of FIG. 29).

That is, as shown in FIG. 24A, the moving force of the link member 90 along the arrow D2 direction is the first and second pressing of the link member 90 in contact with the first and second inclined surfaces 910 and 915. It is transmitted to the coupling retracting member 80 via the portions 808 and 810. The coupling retracting member 80 is a lower device in FIG. 24 as the first and second pressing portions 808 and 810 come into contact with the first and second inclined surfaces 910 and 915 of the link member 90 and are pushed down. It stops at a retracted position displaced in a direction close to the surface of the substrate 51.

As shown in FIG. 30, the coupling retracting member 80 pulls the photoconductor main coupling 71 and the developing device main coupling 72 inserted into the two insertion holes 805 and 806 as the operation moves to the retracting position. The first and second coil springs 714 and 725 are pushed down against the urging force to separate the photoconductor main coupling 71 and the developer main coupling 72 from the photoconductor slave coupling 74 and the developer slave coupling 75. As a result, as shown in FIG. 16, the drive transmission mechanism 70 is transferred from the photoconductor main coupling 71 and the developing device main coupling 72 on the apparatus main body 1a side to the photoconductor slave coupling 74 and developing on the process cartridge 300 side. The transmission of the rotational driving force to the device-subordinate coupling 75 is released.

At that time, as shown in FIG. 23, the rotary cam 85 is rotationally driven along with the movement of the link member 90 along the arrow D2 direction, and the first cam portion 852 of the rotary cam 85 is the coupling retracting member 80. By pushing down the step portion 812, the movement of the coupling retracting member 80 by the link member 90 is assisted. The timing at which the rotary cam 85 assists the movement of the coupling retracting member 80 is set after the link member 90 starts moving the coupling retracting member 80 to the retracting position.

Further, in the rotary cam 85, as shown in FIG. 31, the second cam portion 853 comes into contact with the third contact portion 733 of the fixing device main coupling 73, and the fixing device main coupling 73 is brought into contact with the third coil spring 735. By pushing down against the urging force of, the fixing device main coupling 73 is separated from the fixing device slave coupling 79, and the engagement state between the fixing device main coupling 73 and the fixing device slave coupling 79 is released. .. By doing so, the drive transmission mechanism 70 releases the transmission of the rotational driving force from the fixing device main coupling 73 to the fixing device sub-coupling 79.

Further, as shown in FIG. 26, the moving force of the link member 90 along the arrow D2 direction pushes down the toner supply main coupling 76 through the third inclined surface 920 of the toner supply retracting portion 909, thereby pushing down the toner. The supplier coupling 76 is separated from the toner supply slave coupling 77 against the urging force of the fourth coil spring 764. By doing so, the drive transmission mechanism 70 releases the transmission of the rotational driving force from the toner supply main coupling 76 to the toner supply slave coupling 77, as shown in FIG.

In this way, in the image forming apparatus 1, the transmission of the rotational driving force by the drive transmission mechanism 70 to the process cartridge 300, the toner cartridge 145, the fixing device 40, and the like is released as the front cover 101 is opened. .. Therefore, in the image forming apparatus 1, as shown in FIG. 5, the process cartridge 300 and the toner cartridge 145 can be attached to and detached from the apparatus main body 1a, and the process cartridge 300 and the toner cartridge 145 are attached or replaced.

On the other hand, in the image forming apparatus 1, the front cover 101 is closed when the replacement work of the toner cartridge 145 and the process cartridge 300 is completed.

When the front cover 101 is closed, as shown in FIG. 27A, the drawer inclined surface 174 of the contact acting portion 17 on the front cover 101 comes into contact with the acting protrusion 673 of the rotating body 67, and the rotating body 67 Starts to rotate in the direction indicated by the arrow E2. As a result, the operating force due to the rotational movement generated by the rotating body 67 rotating in the direction indicated by the arrow E2 is transmitted to the link member 90 via the acting arm 66, and the link member 90 is moved along the direction of the arrow D1. Move only the required amount.

As shown in FIG. 6, when the link member 90 moves by a required amount along the direction of arrow D1, the coupling retracting member 80 moves away from the surface of the device substrate 51 as the link member 90 moves. Displace.

That is, as shown in FIG. 24B, the moving force of the link member 90 along the arrow D1 direction is the first of the coupling retracting members 80 that come into contact with the first and second ribs 913 and 918 of the link member 90. It is transmitted to the coupling retracting member 80 via the first and second push upper portions 809 and 811. When the link member 90 moves along the direction of arrow D1, the coupling retracting member 80 is pushed up by contacting the first and second push upper portions 809 and 811 of the link member 90 with the first and second ribs 913 and 918. , The drive position in which the first and second pressing portions 808 and 810 are in contact with the flat surfaces 914 and 919 of the link member 90 by being displaced in the direction away from the surface of the device substrate 51 which is the upper side in FIG. 24. Stop at.

As shown in FIG. 8, the coupling retracting member 80 causes the photoconductor main coupling 71 and the developing device main coupling 72 to move to a drive position in a direction away from the surface of the device substrate 51. The urging forces of the first and second coil springs 714 and 725 displace the photoconductor-sub-coupling 74 and the developing device-sub-coupling 75 into a driving position. By doing so, as shown in FIG. 17, the drive transmission mechanism 70 has the photoconductor main coupling 71 on the apparatus main body 1a side and the developer main coupling 72, and the photoconductor-subordinate coupling 74 on the process cartridge 300 side. And, it is engaged with the developing device slave coupling 75 so that the rotational driving force can be transmitted.

At that time, as shown in FIG. 32, the rotary cam 85 is rotationally driven as the link member 90 moves along the arrow D1 direction, and the first cam portion 852 is separated from the step portion 812 to retract the coupling. Allows the member 80 to move upward. The timing at which the rotary cam 85 allows the coupling retracting member 80 to move is such that the first and second push-up portions 809 and 811 of the coupling retracting member 80 are along the first and second inclined surfaces 911 and 915 of the link member 90. It is set after starting the movement.

Further, in the rotary cam 85, as shown in FIG. 32, the second cam portion 853 is separated from the third contact portion 733 of the fixing device coupling 73 to release the pressing down of the fixing device main coupling 73. The fixing device main coupling 73 is coupled to the fixing device slave coupling 79 by the urging force of the third coil spring 795. By doing so, the drive transmission mechanism 70 is in a state in which the rotational driving force is transmitted from the fixing device main coupling 73 to the fixing device sub-coupling 79.

Further, as shown in FIG. 26, the moving force of the link member 90 along the arrow D1 direction releases the pushed-down state of the toner supply main coupling 76 via the third inclined surface 920 of the toner supply retracting portion 909. As a result, the toner supply main coupling 76 is coupled with the toner supply slave coupling 77 by the urging force of the fourth coil spring 764. By doing so, the drive transmission mechanism 70 transmits the rotational driving force from the toner supply main coupling 76 to the toner supply slave coupling 77.

As described above, in the drive device 50 to which the drive transmission mechanism 70 according to the above embodiment is applied, the photoconductor main coupling 71 and the developing device main coupling 72 on the device main body 1a side are subordinate to the photoconductor on the process cartridge 300 side. The operation of engaging with the coupling 74 and the developing device secondary coupling 75 so that the rotational driving force can be transmitted, and the photoconductor main coupling 71 and the developing device main coupling 72 on the device main body 1a side are the process cartridges. Both the operation of releasing the transmission of the rotational driving force away from the photoconductor slave coupling 74 and the developer slave coupling 75 on the 300 side are axial to the photoconductor main coupling 71 and the developer main coupling 72. It is executed by the coupling retracting member 80 which is displaced along.

Therefore, the photoconductor main coupling 71 and the developer main coupling 72 on the device main body 1a side are the photoconductor slave coupling 74 and the developer slave coupling 75 on the process cartridge 300 side as the coupling retracting member 80 is displaced. It moves along the axial direction of the rotating shafts C1 and C2 when engaged with and separated from the rotating shafts C1 and C2, and avoids moving in a state of being inclined with respect to the rotating shafts C1 and C2. As a result, the photoconductor main coupling 71 and the developing device main coupling 72 are inclined with respect to the rotation axes C1 and C2 when they are engaged with and separated from the photoconductor slave coupling 74 and the developing device slave coupling 75. In this state, the so-called scooping operation of contacting the photoconductor slave coupling 74 and the developing device slave coupling 75 is avoided.

As described above, in the drive device 50 to which the drive transmission mechanism 70 according to this embodiment is applied, the photoconductor main coupling 71 and the developer main coupling 72 are the photoconductor slave coupling 74 and the developer slave coupling 75. Since the scooping operation is avoided, the photoconductor main coupling 71 and the developer main coupling 72, the photoconductor slave coupling 74 and the developer slave coupling 75 are unevenly worn, and the rotational driving force is transmitted. The decrease in accuracy is prevented or suppressed, and the photoconductor drum 11 mounted on the process cartridge 300, the developing roll 14 of the developing apparatus 14, and the like can be rotationally driven with high accuracy for a long period of time.

Further, in the drive device 50 to which the drive transmission mechanism 70 according to this embodiment is applied, as shown in FIG. 12, the drive transmission shaft 581 of the developing device drive gear 58 is provided with the first gap forming portion 584 and is developed. With a simple configuration in which the second gap forming portion 726 is provided in the apparatus main coupling 72, the developing apparatus driving gear 58 is allowed to tilt with respect to the driving transmission shaft 581 of the developing apparatus driving gear 58. The rotational driving force can be transmitted from the developing device to the main coupling 72 of the developing device.

Therefore, the developing device driving gear 58 does not need to be separately provided with a connecting member for transmitting the rotational driving force, and is oriented in the axial direction of the developing device driving gear 58 and the developing device main coupling 72 for transmitting and releasing the rotational driving force. It is possible to reduce the size along the line.

Comparative Example On the other hand, in the case of Patent Document 1 described above, the first drive gear that is rotationally driven by the drive source and the first drive gear can be moved in the eccentric direction and the axial direction and can be rotationally transmitted. The connecting member must be supported by a coil spring along the axial direction of the first drive gear so as to be movable in the eccentric direction and the axial direction and can be rotationally transmitted. There is no choice but to increase the dimensions.

In the above-described embodiment, the image forming apparatus for forming a monochrome image has been described as the image forming apparatus, but four color toners of yellow (Y), magenta (M), cyan (C) and black (K) have been described. Of course, the same can be applied to a full-color image forming apparatus that forms an image.

Further, in the above-described embodiment, the photoconductor coupling and the developing device coupling have been described as an example as the first drive transmission means which is movably arranged along the axial direction of the plurality of adjacent rotation axes. The present invention is not limited to this, and of course, it can be applied to a plurality of photoconductor drums having a plurality of adjacent rotation axes.

1 ... Image forming device 1a ... Image forming device main body 11 ... Photoconductor drum 14 ... Developing device 40 ... Fixing device 50 ... Driving device 58 ... Developing device driving gear 72 ... Developing device Main coupling 80 ... Coupling retracting member 90 ... Link Element

Claims (9)

A drive means that has a drive transmission shaft provided with a plurality of convex portions on the outer circumference and is rotationally driven.
A drive that is movably mounted along the axial direction of the drive transmission shaft through a mounting hole having a plurality of concave portions on the inner circumference that engage with the plurality of convex portions, and a rotational driving force is transmitted from the driving means. Means of communication and
A gap forming portion provided at the tip of the drive transmission shaft and the base end of the mounting hole to form a gap that allows the drive transmission shaft to tilt in a state where the convex portion and the concave portion are engaged with each other.
Covering means arranged on one side surface along the axial direction of the driving means, and
With
The covering means is a drive transmission mechanism having a sliding portion that contacts and rotatably supports the cylindrical portion of the drive means toward the inside along the axial direction of the drive means . The drive transmission mechanism according to claim 1, wherein the gap forming portion has a different angle that allows the inclination of the drive transmission shaft depending on the engagement state between the convex portion and the concave portion. The drive transmission mechanism according to claim 2, wherein the gap forming portion comprises a rounded surface provided at the tip of the drive transmission shaft of the drive means and a cut surface provided at the base end of the mounting hole. The drive transmission mechanism according to claim 1, wherein the drive transmission means is urged by the urging means in a direction away from the drive means. The drive transmission mechanism according to claim 4, wherein the urging means is arranged on the outer periphery of the drive transmission shaft of the drive means. The driving force according to any one of claims 1 to 5, wherein the drive transmitting means has a plurality of second convex portions for transmitting the driving force to other drive transmitting means on the outer periphery of the tip end portion of the drive transmitting shaft. Transmission mechanism. The driving force transmission mechanism according to claim 6, wherein the plurality of second convex portions are provided at positions corresponding to the plurality of convex portions of the drive transmission shaft. With the drive source
Driven means to be driven by transmitting rotational driving force from the drive source, and
A drive transmission means for transmitting and releasing a rotational driving force from the drive source,
With
A drive device using the drive transmission mechanism according to any one of claims 1 to 7 as the drive transmission means. Image forming means and
The driving means for driving the image forming means and
With
An image forming apparatus using the driving device according to claim 8 as the driving means.

Images