JP6398516B2 - Conveying apparatus, image reading apparatus, and image forming apparatus - Google Patents

Description

  The present invention relates to a conveyance device, an image reading device, and an image forming apparatus.

  In a conventional image forming apparatus, techniques disclosed in Patent Documents 1 and 2 below are known regarding a conveying apparatus that conveys a document toward a reading position.

Japanese Patent Application Laid-Open No. 2012-101941 as Patent Document 1 uses a solenoid (122) as a configuration for bringing a discharge roller (111) into contact with and separating from a discharge roller (110) in a double-sided document reading apparatus. A technique for detecting separation using a separation detection sensor (125) is described.
Further, in Patent Document 1, a gear portion (441) having a chipped portion is formed on the elevating cam (144) as a configuration in which the discharge roller (140) is separated from the discharge roller (139) for a certain period. A claw-like locking part (442) that is locked by a lever (146) is provided on the part (441), and when the lever (146) is separated from the locking part (442), the spring (138) is raised and lowered. A configuration in which the cam (144) is rotated to separate the paper discharge roller (140) from the paper discharge roller (139) is also described.

  Japanese Patent Application Laid-Open No. 2007-217179 as Patent Document 2 discloses that when the document is turned upside down, the pulling of the document between the discharge roller pair (24) and the conveyance roller pair (23) is eliminated. A technique for operating the separation solenoid (36) to eliminate the nip of the discharge roller pair (24) is described.

JP 2012-101941 A (“0095” to “0096”, “0109” to “0112”, FIGS. 18 and 23) JP 2007-217179 A (“0037”, FIG. 9)

  It is a technical object of the present invention to move a pair of conveying members to a preset position while reducing costs when contacting and separating the pair of conveying members.

In order to solve the technical problem, the transport device according to claim 1 comprises:
A pair of conveying members;
A connecting member connected to one of the pair of transport members and relatively moving in a direction in which the pair of transport members are in contact with or separated from each other;
An operating member supported rotatably about a rotation axis, wherein the first engaging portion engages with the connecting member and contacts the pair of conveying members; and the first engaging portion And a second engaging portion that is disposed at a position whose phase is shifted by less than 180 degrees in the circumferential direction of the operating member, and engages with the connecting member to separate the pair of transport members. When,
A stopped member that is rotatably supported in conjunction with the actuating member, the first stopped portion disposed corresponding to the first engaging portion, and the second engaging portion. A second stopped portion correspondingly disposed, and the stopped member,
A stop member that engages with each of the stopped parts to stop the rotation of the stopped member, and engages with any of the stopped parts to hold the position of the operating member; The stop member movable between a release position where the engagement with each stopped portion is released, and
Contact / separation control means for controlling the stop member to control contact and separation of the pair of transport members, moving the stop member to the engagement position and moving the actuating member to the second engagement member. The first rotation amount is rotated along the rotation direction from the joint portion to the first engagement portion, and then the stop member is moved to the release position and the operating member is moved from the first engagement portion. A predetermined second rotation amount exceeding the rotation amount to the second engagement portion is rotated, and then the stop member is moved to the engagement position and the operation member is moved from the rotation amount for one rotation. The contact / separation control means for rotating the third rotation amount by subtracting the second rotation amount;
It is provided with.

Invention of Claim 2 is the conveying apparatus of Claim 1,
A first gear member to which driving is transmitted from a driving source, and a second gear formed integrally with the stopped member and supported so as to be movable coaxially and relatively with respect to the operating member A first gear portion that is formed on the outer periphery and transmits drive when meshed with the first gear member, and is disposed with a gap in the circumferential direction with respect to the first gear portion. And a second gear portion to which drive is transmitted when meshed with the first gear member, and the gap between the first gear portion and the second gear portion is the When each stopped portion engages with the stop member, the second gear member disposed at a position facing the first gear member , and a rotation direction set in advance on the second gear member A rotational force imparting member that imparts rotational force to the drive transmission system,
It is provided with.

The invention according to claim 3 is the transfer device according to claim 1 or 2,
The pair of conveying members includes a driving member to which driving is transmitted, and a driven member that is disposed to face the driving member and can be driven to rotate with a document interposed therebetween.

Invention of Claim 4 is the conveying apparatus in any one of Claim 1 thru | or 3,
A document stacking unit on which the document is loaded;
A document discharge section for discharging the document;
A document transport path extending from the document stacking section through the document reading position to the document discharge section;
The pair of conveying members disposed in the document conveying path and conveying the document toward the document discharge section;
A reversing path that connects the upstream side of the pair of transport members and the upstream side of the document reading position with respect to the document transport direction, and transports the document to be read on the second side;
It is provided with.

In order to solve the technical problem, an image reading apparatus according to claim 5 is provided.
An imaging member for reading an image of a document;
The conveyance device according to claim 1, wherein the imaging member conveys a document to a reading position where the document is read.
It is provided with.

In order to solve the technical problem, an image forming apparatus according to a sixth aspect of the present invention provides:
An image reading apparatus according to claim 5 for reading an image of a document;
An image recording apparatus for recording an image read by the image reading apparatus on a medium;
It is provided with.

According to the first, fifth, and sixth aspects of the present invention, when the pair of conveying members are brought into contact with and separated from each other as compared with the case where the member for detecting the position of the operating member is provided, the cost is set in advance. Can be moved to a different position.
According to the second aspect of the present invention, the drive can be transmitted from the first gear member by the first gear portion and the second gear portion without providing a member for switching the drive transmission. When the gap is made to face the first gear member, the drive can be made non-transmitted.
According to the third aspect of the present invention, when the drive member and the driven member are brought into contact with or separated from each other, the drive member can be moved to a preset position.
According to the fourth aspect of the present invention, the pair of conveying members on the upstream side of the discharge portion in the configuration capable of reading both sides of the original can be contacted and separated.

FIG. 1 is an explanatory diagram of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is an enlarged explanatory view of a main part of the document conveying apparatus according to the first embodiment. 3A and 3B are explanatory diagrams of a transmission system of the document conveying apparatus according to the first exemplary embodiment. FIG. 3A is a perspective view, and FIG. 4A and 4B are explanatory views of the contact / separation mechanism according to the first embodiment. FIG. 4A is a view seen from the front, and FIG. 4B is a view seen from the rear. FIG. 5 is an exploded explanatory view of the elevating gear according to the first embodiment. FIG. 6 is an explanatory diagram of the operation of the lifting gear of the first embodiment, FIG. 6A is an explanatory diagram of the initial position, FIG. 6B is an explanatory diagram when the solenoid is turned on from the state shown in FIG. 6A, and FIG. FIG. 6D is an explanatory view when the lifting gear is rotated from the state shown in FIG. 6B and the solenoid is turned off, and FIG. 6D is a state in which the lifting gear is rotated from the state shown in FIG. 6C and the lock lever is in contact with the second lock claw. It is explanatory drawing. FIG. 7 is an explanatory view of the operation of the lifting gear continued from FIG. 6, FIG. 7A is an explanatory view of the state where the lifting gear is rotated from the state shown in FIG. 6D and the driven roll is separated from the driving roll, and FIG. 7C is an explanatory diagram when the solenoid is turned on from the state shown in FIG. 7A, FIG. 7C is an explanatory diagram when the lifting gear is rotated from the state shown in FIG. 7B and the solenoid is turned off, and FIG. 7D is shown in FIG. It is explanatory drawing of the state which the raising / lowering gear rotated from the state and the lock lever contacted the 1st lock nail | claw. FIG. 8 is a block diagram illustrating the functions of the control unit of the image forming apparatus according to the first embodiment. FIG. 9 is an explanatory diagram of a flowchart of the exit roll contact / separation process according to the first embodiment. FIG. 10 is an explanatory diagram of the operation of returning the lifting gear to the initial position according to the first embodiment, and FIG. 10A is an explanatory diagram when the lock lever is positioned downstream of the first lock claw when the power is turned on. 10B is an explanatory diagram when the lock lever is positioned upstream of the second lock claw when the power is turned on, and FIG. 10C is a diagram illustrating when the lock lever is located upstream of the first lock claw and the second lock claw when the power is turned on. It is explanatory drawing in the case of being located in the downstream.

Next, specific examples of embodiments of the present invention (hereinafter referred to as examples) will be described with reference to the drawings, but the present invention is not limited to the following examples.
In order to facilitate understanding of the following description, in the drawings, the front-rear direction is the X-axis direction, the left-right direction is the Y-axis direction, the up-down direction is the Z-axis direction, and arrows X, -X, Y, -Y, The direction indicated by Z and -Z or the indicated side is defined as the front side, the rear side, the right side, the left side, the upper side, the lower side, or the front side, the rear side, the right side, the left side, the upper side, and the lower side, respectively.
In the figure, “•” in “○” means an arrow heading from the back of the page to the front, and “×” in “○” is the front of the page. It means an arrow pointing from the back to the back.
In the following description using the drawings, illustrations other than members necessary for the description are omitted as appropriate for easy understanding.

FIG. 1 is an explanatory diagram of an image forming apparatus according to a first embodiment of the present invention.
In FIG. 1, a copier U as an example of an image forming apparatus according to the first exemplary embodiment is an example of a recording unit, and includes a printer unit U1 as an example of an image recording apparatus. A scanner unit U2 as an example of a reading unit and an example of an image reading device is supported on the upper portion of the printer unit U1. An auto feeder U3 as an example of a document transport device is supported on the upper portion of the scanner unit U2. The scanner unit U2 of the first embodiment supports a user interface U0 as an example of an input unit. The user interface U0 can be operated by the operator by inputting the user interface U0.

  A document tray TG1 as an example of a medium container is disposed on the upper part of the auto feeder U3. A plurality of documents Gi to be copied can be stacked and stored in the document tray TG1. A document discharge tray TG2 as an example of a document discharge unit is formed below the document tray TG1. A document transport roll U3b is disposed between the document tray TG1 and the document discharge tray TG2 along the document transport path U3a.

A platen glass PG as an example of a transparent document table is disposed on the upper surface of the scanner unit U2. In the scanner unit U2 of the first embodiment, a reading optical system A is disposed below the platen glass PG. The optical system A for reading in Example 1 is supported so as to be movable in the left-right direction along the lower surface of the platen glass PG. The reading optical system A is normally stopped at the initial position shown in FIG.
On the right side of the optical system A for reading, an imaging element CCD as an example of an imaging member is arranged. An image processing unit GS is electrically connected to the image sensor CCD.
The image processing unit GS is electrically connected to the writing circuit DL of the printer unit U1. The writing circuit DL is electrically connected to an exposure apparatus ROS as an example of a latent image forming apparatus.

In the printer unit U1, a photosensitive drum PR as an example of an image holding member is disposed. Around the photosensitive drum PR, a charging roll CR as an example of a charging member, a developing device G, a transfer unit TU as an example of a transfer device, and a drum cleaner CLp as an example of a cleaner are arranged.
On the right side of the developing device G, a cartridge K as an example of a developer container is disposed. The cartridge holder KS that supports the cartridge K and the developing device G are connected by a developer transport device GH having a reserve tank RT.

Below the transfer unit TU, paper feed trays TR1 to TR4 as examples of medium storage containers are arranged. A conveyance path SH1 extends from each of the paper feed trays TR1 to TR4. In the transport path SH1, a pick-up roll Rp as an example of a medium take-out member, a scoop roll Rs as an example of a scooping member, a transport roll Ra as an example of a transport member, and a registration roll Rr as an example of a delivery member are arranged. Yes.
A fixing device F having a heating roll Fh and a pressure roll Fp is disposed on the left side of the transfer unit TU. The fixing device F and the paper discharge tray TRh are connected by a discharge path SH2. The discharge path SH2 and the registration roll Rr are connected by an inversion path SH3. In the discharge path SH2, a transport roll Rb and a discharge roll Rh that can rotate in the forward and reverse directions are arranged.

(Description of image forming operation)
The plurality of documents Gi stored in the document tray TG1 sequentially passes through the document reading position on the platen glass PG and is discharged to the document discharge tray TG2.
When the automatic feeder U3 is used to automatically convey and copy a document, each document that sequentially passes through the reading position on the platen glass PG with the reading optical system A stopped at the initial position. Gi is exposed.
When the operator places the document Gi on the platen glass PG by hand, the optical system A for reading moves in the left-right direction, and the document on the platen glass PG is scanned while being exposed.
The reflected light from the original document Gi passes through the optical system A for reading and is condensed on the image sensor CCD. The image pickup device CCD converts the reflected light of the original collected on the image pickup surface into an electric signal.

The image processing unit GS converts the read signal input from the image sensor CCD into a digital image signal and outputs the digital image signal to the writing circuit DL of the printer unit U1. The writing circuit DL outputs a control signal corresponding to the input image writing signal to the exposure apparatus ROS.
The exposure apparatus ROS outputs a laser beam L and forms a latent image on the surface of the photosensitive drum PR charged by the charging roll CR. The latent image on the surface of the photosensitive drum PR is developed into a visible image by the developing device G. The transfer roll TR of the transfer unit TU transfers the visible image on the surface of the photosensitive drum PR to a recording sheet S as an example of a medium that has been transported through the transport path SH1. The visible image transferred to the recording sheet S is fixed by the fixing device F. The recording sheet S that has passed through the fixing device F is conveyed to the reverse path SH3 when duplex printing is performed, and is discharged by the discharge roll Rh when discharged to the discharge tray TRh.

(Description of auto-feeder U3)
FIG. 2 is an enlarged explanatory view of a main part of the document conveying apparatus according to the first embodiment.
1 and 2, the auto-feeder U3 as an example of the document conveying apparatus according to the first embodiment has a C-shaped document conveyance path U3a from the document tray TG1 to the document discharge tray TG2.
A nudger roll 1 as an example of a document take-out member is disposed at the upper right part of the document transport path U3a of the first embodiment, that is, at the upstream end of the document Gi in the transport direction. On the left side of the nudger roll 1, there is disposed a document separating roll 2 as an example of a document separating member.

A takeaway roll 3 as an example of a document transport member is disposed downstream of the document handling roll 2 in the transport direction of the document Gi. An original registration roll 4 as an example of an original feed timing adjustment member is disposed downstream of the take-away roll 3 in the transport direction of the original Gi.
An image reading position 6 at which an image is read is set on the platen glass PG on the downstream side in the conveyance direction of the document Gi with respect to the document registration roll 4.
An out-roll 7 as an example of a document conveying member is arranged downstream of the image reading position 6 as an example of a document reading position in the conveyance direction of the document Gi.

An exit roll 8, which is an example of a document transport member and an example of a document discharge member, is disposed downstream of the out-roll 7 in the transport direction of the document Gi.
A document reversing path 11 is formed between the upstream side of the exit roll 8 and the upstream side of the takeaway roll 3 with respect to the transport direction of the document Gi.
On the upstream side of the exit roll 8, a gate 12, which is an example of a conveyance switching member, is disposed at a branch portion between the document reversing path 11 and the document conveying path U 3 a. Further, on the upstream side of the take-away roll 3, a gate 13 as an example of a conveyance switching member is disposed at a junction between the document reverse path 11 and the conveyance path U3a.

  In the document transport path U3a according to the first exemplary embodiment, a pre-registration sensor 16 as an example of a medium detection member is disposed in the vicinity of the upstream side of the takeaway roll 3. A registration sensor 17 as an example of a medium detection member is disposed in the vicinity of the downstream side of the document registration roll 4. Further, a discharge sensor 18 as an example of a medium detection member is disposed on the upstream side of the exit roll 8.

(Description of the transmission system of the document feeder)
3A and 3B are explanatory diagrams of a transmission system of the document conveying apparatus according to the first exemplary embodiment. FIG. 3A is a perspective view, and FIG.
In FIG. 3, the exit roll 8 according to the first embodiment includes a drive roll 21 as an example of a drive member disposed below. A driven roll 22 as an example of a driven member is disposed above the drive roll 21. The shaft of the driven roll 22 is rotatably supported at the tip of an arm 23 as an example of a support member. The base end of the arm 23 is rotatably supported by a support shaft 24 extending in the front-rear direction. A pressing support portion 23 a is formed at the base end portion of the arm 23. One end of a coil spring 26 as an example of a pressing member is supported on the pressing support portion 23a. The coil spring 26 urges the pressing support portion 23a upward. Therefore, the driven roll 22 is pressed against the drive roll 21 by the force of the coil spring 26.

  Note that the material of the drive roll 21 is such that the friction coefficient μ1 between the drive roll 21 and the document Gi satisfies μ1> μ2 with respect to the friction coefficient μ2 between the document Gi. Is selected, and the surface of the drive roll 21 is subjected to high friction processing. That is, the drive roll 21 is configured so that μ1> μ2 even for the document Gi having the largest μ2 among the paper types of the document Gi that can be used by the auto feeder U3. Accordingly, the length of the document Gi in the transport direction is long, and at the position of the exit roll 8, the rear portion of the document Gi is transported to the reverse path 11 and the front portion of the document Gi is transported toward the document discharge tray TG2. Even in this case, the front part can be conveyed by the drive roll 21 toward the document discharge tray TG2, and the rear part can be conveyed by the takeaway roll 3.

A first lever 27 as an example of a first connecting member is supported at the rear end of the support shaft 24. The first lever 27 is rotatably supported integrally with the support shaft 24. The first lever 27 has a pushed-up portion 27a extending rightward.
A second lever 28 is supported on the right side of the first lever 27. The second lever 28 is supported by a frame (not shown) so as to be rotatable about the shaft portion 28a. A push-up portion 28b is formed on the left side of the shaft portion 28a. The push-up portion 28 b extends toward the pushed-up portion 27 a of the first lever 27. The upper surface of the push-up portion 28b is configured to be able to contact the lower surface of the pushed-up portion 27a.

A biased portion 28c extending leftward is formed behind the push-up portion 28b. One end of a coil spring 29 as an example of a biasing member is connected to the left end of the biased portion 28c. The other end of the coil spring 29 is supported by a frame (not shown). The coil spring 29 applies a force that pulls the biased portion 28c downward. The second lever 28 has a cam contact portion 28d extending rightward and downward from the shaft portion 28a as an example of a contact portion of the operating member.
The first lever 27, the second lever 28, and the coil spring 29 constitute the connecting members 27 to 29 of the first embodiment.

A motor unit M2 as an example of a drive source is supported at the rear portion of the auto feeder U3. In addition, the motor unit M2 of Example 1 is configured by a motor unit that can rotate forward and reverse.
A drive gear 32 as an example of a gear is supported on the output shaft 31 of the motor unit M2. The drive gear 32 is engaged with a first intermediate gear 33 as an example of a gear. A second intermediate gear 34 as an example of a gear is supported on the same axis as the first intermediate gear 33. A third intermediate gear 36 as an example of a gear meshes with the second intermediate gear 34.
An exit gear 37 as an example of a gear meshes with the third intermediate gear 36. The exit gear 37 is supported at the rear end of the shaft 38 of the drive roll 21 of the exit roll 8.

The third intermediate gear 36 meshes with a fourth intermediate gear 41 as an example of a gear. A fifth intermediate gear 42 as an example of a gear is supported on the same axis as the fourth intermediate gear 41 via a clutch as an example of a drive switching member. A sixth intermediate gear 43 as an example of a gear meshes with the fifth intermediate gear 42. The sixth intermediate gear 43 is engaged with a gear of the shaft of the document separating roll 2 (not shown). The nudger roll 1 is configured to be able to transmit drive from the document separating roll 2 via a gear (not shown).
The second intermediate gear 34 is engaged with a seventh intermediate gear 46 as an example of a gear. A first pulley 47 as an example of a rotation transmission member is coaxially supported in front of the seventh intermediate gear 46. Below the first pulley 47, a second pulley 48 as an example of a rotation transmission member is disposed. The second pulley 48 is supported on the drive shaft 49 of the out roll 7.

On the left side of the second pulley 48, a third pulley 51 as an example of a rotation transmission member is disposed. On the left side of the third pulley 51, a fourth pulley 52 as an example of a rotation transmission member is disposed. The fourth pulley 52 is supported on the drive shaft 53 of the document registration roll 4.
A fifth pulley 54 as an example of a rotation transmission member is disposed on the upper right side of the fourth pulley 52. A transmission belt 56 as an example of a rotation transmission member is placed between the pulleys 47 to 54.

Behind the seventh intermediate gear 46, an eighth intermediate gear 61 as an example of a gear is supported coaxially. A swing arm 62 as an example of a switching member is supported on the shafts of the seventh intermediate gear 46, the first pulley 47, and the eighth intermediate gear 61. The central portion of the swing arm 62 is supported so as to be rotatable with respect to the shaft of the seventh intermediate gear 46 and the like.
A ninth intermediate gear 63 as an example of a gear is supported on the swing arm 62. A tenth intermediate gear 64 as an example of a gear is supported at the lower part of the swing arm 62. Both the ninth intermediate gear 63 and the tenth intermediate gear 64 mesh with the eighth intermediate gear 61.

An eleventh intermediate gear 66 as an example of a gear is disposed on the left side of the eighth intermediate gear 61. The eleventh intermediate gear 66 is supported on the shaft 67 of the takeaway roll 3.
In FIG. 3B, a twelfth intermediate gear 69 as an example of a gear is rotatably supported on the rear portion of the shaft 68 of the third pulley 51. The twelfth intermediate gear 69 meshes with the eleventh intermediate gear 66.

In the swing arm 62, when the motor unit M2 is driven to rotate in the forward direction, the gears 32 to 69 rotate in the directions indicated by the solid line arrows in FIG. Therefore, the ninth intermediate gear 63 and the tenth intermediate gear 64 move along the outer periphery of the eighth intermediate gear 61, resulting in the state shown in FIGS. 3A and 3B. Accordingly, the ninth intermediate gear 63 is engaged with the eleventh intermediate gear 66 and the tenth intermediate gear 64 is separated from the twelfth intermediate gear 69.
On the other hand, when the motor unit M2 is driven in reverse rotation, the gears 32 to 69 rotate in the directions indicated by the broken-line arrows in FIG. Therefore, the ninth intermediate gear 63 and the tenth intermediate gear 64 move along the outer periphery of the eighth intermediate gear 61. Then, the ninth intermediate gear 63 is separated from the eleventh intermediate gear 66, and the tenth intermediate gear 64 is engaged with the twelfth intermediate gear 69.

(Explanation of rotation transmission to each roll)
Therefore, in the drive transmission systems 31 to 79 of the first embodiment, when the motor unit M2 is driven to rotate in the forward direction, the forward rotation is transmitted from the drive gear 32 to the exit gear 37 through the intermediate gears 33 to 36. Therefore, the drive roll 21 of the exit roll 8 rotates in a direction in which the document Gi is conveyed toward the document discharge tray TG2. Further, the document registration roll 4 and the out roll 7 are rotated through a drive gear 32, a first intermediate gear 33, a second intermediate gear 34, a seventh intermediate gear 46, pulleys 47 to 54, and a transmission belt 56. Then, the document Gi is rotated in the direction of transporting the document Gi toward the downstream side in the transport direction.

  Further, the takeaway roll 3 includes a drive gear 32, a first intermediate gear 33, a second intermediate gear 34, a seventh intermediate gear 46, an eighth intermediate gear 61, a ninth intermediate gear 63, and an eleventh gear. Rotation is transmitted through the intermediate gear 66 and the document Gi is rotated in the direction of transporting toward the downstream side in the transport direction. In addition, the rotation is transmitted to the document separating roll 2 and the nudger roll 1 via the drive gear 32 and the intermediate gears 33 to 36 and 41 to 43, and the document Gi is transported toward the downstream side in the transport direction. Rotate to. Note that the rotation is transmitted to the document separating roll 2 and the nudger roll 1 when a clutch provided in the fourth intermediate gear 41 is connected, and the rotation is not transmitted when the clutch is disconnected.

  In the drive transmission systems 31 to 69 according to the first embodiment, when the motor unit M2 rotates in the reverse direction, the drive is transmitted in the same manner as in the normal rotation, and the exit roll 8, the document registration roll 4, and the out roll 7 rotate in the reverse direction. On the other hand, the takeaway roll 3 includes a drive gear 32, a first intermediate gear 33, a second intermediate gear 34, a seventh intermediate gear 46, an eighth intermediate gear 61, a tenth intermediate gear 64, a twelfth gear. Rotation is transmitted through the intermediate gear 69 and the eleventh intermediate gear 66, and the same document Gi as that in the forward rotation is rotated in the direction of conveyance toward the downstream side in the conveyance direction. That is, the takeaway roll 8 of the first embodiment rotates in the same rotational direction regardless of whether the motor unit M2 rotates forward or backward. In the original document roll 2 and the nudger roll 1 of the first embodiment, the clutch is disconnected and the reverse rotation is not transmitted.

(Exit roll contact and separation mechanism explanation)
4A and 4B are explanatory views of the contact / separation mechanism according to the first embodiment. FIG. 4A is a view seen from the front, and FIG. 4B is a view seen from the rear.
FIG. 5 is an exploded explanatory view of the elevating gear according to the first embodiment.
3 to 5, an elevating gear 71 as an example of a second gear member is arranged on the right side of an exit gear 37 as an example of a first gear member. The elevating gear 71 is rotatably supported by a shaft 72 as an example of a shaft. The elevating gear 71 has a cam gear 73 disposed on the front side and a lock gear 74 disposed on the rear side.

  The cam gear 73 and the lock gear 74 are formed in a disc shape. The outer periphery of the cam gear 73 and the lock gear 74 is formed with a first gear portion 73a, 74a as an example of the first gear portion and a gap in the circumferential direction with respect to the first gear portion 73a, 74a. And second gear portions 73b and 74b as an example of the second gear portion. Each gear part 73a, 73b, 74a, 74b is comprised so that rotation can be transmitted, when meshing with the exit gear 37. FIG. In other words, in the first embodiment, the cam gear 73 and the lock gear 74 are set in the axial length and position so that they can mesh with the exit gear 37.

  With respect to the rotation direction Ya of the elevating gear 71 during the forward rotation of the motor unit M2, the gear teeth are missing due to the gap on the downstream side of the first gear portions 73a and 74a and the upstream side of the second gear portions 73b and 74b. First missing tooth portions 73c and 74c, which are parts, are configured. Similarly, second chipped portions 73d and 74d are formed by gaps on the downstream side of the second gear portions 73b and 74b and on the upstream side of the first gear portions 73a and 74a. When the missing tooth portions 73c, 73d, 74c, and 74d face the exit gear 37, the missing tooth portions 73c, 73d, 74c, and 74d are respectively connected to the gear portions 73a, 73b, 74a, and 74b. The width in the circumferential direction is set so that they do not touch. In Example 1, the angle formed by the centers of the respective missing tooth portions 73c, 73d, 74c, and 74d is set to 90 degrees.

4 and 5, the cam gear 73 supports a pin 76 as an example of a guided member that protrudes toward the lock gear 74.
In the lock gear 74, a guide groove 77 as an example of a guide portion is formed corresponding to the pin 76. The guide groove 77 is formed in a partial arc shape with the shaft 72 as the center. The lock gear 74 is formed with a spring support portion 78 as an example of a support portion for the applying member on the surface on the cam gear 73 side.

Between the cam gear 73 and the lock gear 74, a torsion spring 79 as an example of a rotational force applying member is disposed. The torsion spring 79 has one end supported by a pin 76 and the other end supported by a spring support 78. Therefore, the torsion spring 79 gives the cam gear 73 a force for rotating the lock gear 74 in the rotation direction Ya.
The drive transmission systems 31 to 79 according to the first embodiment are configured by the members denoted by the reference numerals 31 to 79.

  On the rear surface of the lock gear 74, a locked member 81 as an example of a stopped member is disposed. The member to be locked 81 of the first embodiment is integrally formed in a coaxial column shape protruding rearward of the lock gear 74. The locked member 81 is formed with a first locking claw 82 as an example of a first stopped portion. A second lock claw 83 is formed at a position shifted in the circumferential direction of the locked member 81 with respect to the first lock claw 82. With respect to the first lock claw 82 of the first embodiment, the second lock claw 83 has a circumferential phase that is 90 degrees upstream with respect to the rotational direction Ya of the elevating gear 71 as an example less than 180 degrees. It is arranged at a position shifted to the side.

  Each of the lock claws 82 and 83 is formed in a claw shape projecting in the radial direction with respect to the outer peripheral surface 81 a of the locked member 81. Each of the lock claws 82 and 83 has step surfaces 82a and 83a whose downstream surfaces with respect to the rotation direction Ya of the elevating gear 71 are in the radial direction. On the upstream side from the outer ends of the step surfaces 82a and 83a, inclined surfaces 82b and 83b that are smoothly connected to the outer peripheral surface 81a are formed.

A lock member 86 as an example of a stop member is disposed on the left side of the locked member 81. The lock member 86 includes a solenoid 87 as an example of a drive source for stopping. The solenoid 87 is constituted by an electromagnetic coil around which a conducting wire is wound around a shaft 87a. Therefore, a magnetic force is generated at the tip of the shaft 87a during energization.
A lock lever 88 as an example of a main body of a stop member is disposed at the tip of the shaft 87a. The lock lever 88 according to the first embodiment is formed of a magnetic plate. The lock lever 88 is supported by a frame body of the lock member 86 so that the base end portion 88 a is rotatable.

A tension spring 89 as an example of a biasing member is supported at the base end of the lock lever 88. The tension spring 89 pulls the base end side of the lock lever 88. Therefore, the lock lever 88 receives a force in a direction away from the shaft 87 a of the solenoid 87 by the elastic force of the tension spring 89.
A lock portion 88b as an example of a stop portion is formed at the distal end portion of the lock lever 88. The lock portion 88b is formed in a shape bent from the lock lever 88 to the locked member 81 side. The lock portion 88b is configured to be engageable with the step surfaces 82a and 83a of the lock claws 82 and 83.

A cam 91 as an example of an operating member is disposed on the front surface of the cam gear 73. The cam 91 according to the first embodiment is integrally formed in a coaxial column shape protruding forward of the cam gear 73. The cam 91 is configured to be able to contact the upper surface of the cam contact portion 28d of the second lever 28.
On the outer peripheral surface of the cam 91, a short-diameter surface 91a having a minimum diameter from the shaft 72 that is the center of rotation is provided as an example of a first engaging portion. Further, a long diameter surface 91b having a maximum diameter as an example of the second engagement portion is provided at a position where the phase is shifted by 90 degrees with respect to the short diameter surface 91a. The short-diameter surface 91a and the long-diameter surface 91b of the first embodiment are formed in a so-called D-cut shape that is cut out in a planar shape so that the rotational position is stable when contacting the cam contact portion 28d.

  The short diameter portion 91a is formed corresponding to a position where the lock portion 88b contacts the cam contact portion 28d when the lock portion 88b contacts the stepped surface 82a of the first lock claw 82. The long diameter portion 91b is formed corresponding to a position where the lock portion 88b contacts the cam contact portion 28d when the lock portion 88b contacts the stepped surface 83a of the second lock claw 83.

(Exit roll contact and separation)
FIG. 6 is an explanatory diagram of the operation of the lifting gear of the first embodiment, FIG. 6A is an explanatory diagram of the initial position, FIG. 6B is an explanatory diagram when the solenoid is turned on from the state shown in FIG. 6A, and FIG. FIG. 6D is an explanatory view when the lifting gear is rotated from the state shown in FIG. 6B and the solenoid is turned off, and FIG. 6D is a state in which the lifting gear is rotated from the state shown in FIG. 6C and the lock lever is in contact with the second lock claw. It is explanatory drawing.
FIG. 7 is an explanatory view of the operation of the lifting gear continued from FIG. 6, FIG. 7A is an explanatory view of the state where the lifting gear is rotated from the state shown in FIG. 6D and the driven roll is separated from the driving roll, and FIG. 7C is an explanatory diagram when the solenoid is turned on from the state shown in FIG. 7A, FIG. 7C is an explanatory diagram when the lifting gear is rotated from the state shown in FIG. 7B and the solenoid is turned off, and FIG. 7D is shown in FIG. It is explanatory drawing of the state which the raising / lowering gear rotated from the state and the lock lever contacted the 1st lock nail | claw.

4 and 6, in the lifting gear 71 of the first embodiment, the solenoid 87 is in an off state at the initial position. Therefore, the lock lever 88 moves to the engagement position shown in FIG. 6A by the elastic force of the tension spring 89. Therefore, the lock lever 88 is held in contact with the first lock claw 82. Therefore, the lock gear 74 is held in the state shown in FIG. 6A.
At this time, in the cam gear 73, the short diameter surface 91a is in contact with the cam contact portion 28d. The short-diameter surface 91a of Example 1 has a flat shape, and the posture is stabilized in a state where the short-diameter surface 91a is in surface contact with the contact portion 28d. Therefore, the rotation of the cam gear 73 is restricted in accordance with the contact between the short diameter surface 91a and the contact portion 28d. Therefore, the cam gear 73 is also held in the state shown in FIG. 6A.

At this time, the elastic force of the torsion spring 79 acts between the cam gear 73 and the lock gear 74.
Therefore, in the initial position shown in FIG. 6A, the first missing tooth portions 73 c and 74 c are held in a state of facing the exit gear 37. Accordingly, no rotational force is transmitted to the lifting gear 71.
In FIG. 4, the biased portion 28 c of the second lever 28 is pulled by the coil spring 29 in this state. Therefore, the push-up portion 28b is held without lifting the pushed-up portion 27a. Thus, the driven roll 22 is held in contact with the drive roll 21 by the coil spring 26.

  6A and 6B, when the solenoid 87 is turned on from the state shown in FIG. 6A, the lock lever 88 is separated from the first lock claw 82. Therefore, the lock gear 74 is in a rotatable state. Therefore, the elastic force of the torsion spring 79 acts, and the lock gear 74 rotates in the direction of the rotation direction Ya. Therefore, as shown in FIG. 6B, the first gear portion 74 a of the lock gear 74 meshes with the exit gear 37.

  6B and 6C, when the first gear portion 74a of the lock gear 74 meshes with the exit gear 37, the lock gear 74 rotates as the exit gear 37 rotates. When the lock gear 74 rotates, the lock gear 74 rotates relative to the cam gear 73 in a range where the pin 76 is inside the guide groove 77. When the pin 76 comes into contact with the end of the guide groove 77, the rotational force is also transmitted to the cam gear 73. Therefore, as shown in FIG. 6C, the cam gear 73 also starts to rotate. When the cam gear 73 starts rotating, the first gear portion 73 a of the cam gear 73 is engaged with the exit gear 37. Therefore, the cam gear 73 and the lock gear 74 rotate by meshing the first gear portions 73a and 74a.

At this time, the cam 91 also rotates, and the contact position with the contact portion 28d changes from the short diameter surface 91a toward the long diameter surface 91b. Therefore, the second lever 28 starts to rotate around the shaft portion 28a. Therefore, the push-up portion 28b starts to push up the pushed-up portion 27a, and the driven roll 22 starts to be separated from the drive roll 21.
In FIG. 6C, when the lock gear 74 rotates corresponding to a separation time t4 described later, the solenoid 87 is turned off. Therefore, the lock lever 88 moves to the engagement position shown in FIG. 6C by the elastic force of the tension spring 89.

  6C and 6D, when the cam gear 73 and the lock gear 74 are rotated, the first gear portion 74a of the lock gear 74 that has been rotated in advance is separated from the exit gear 37. Therefore, no rotational force is applied to the lock gear 74. At this time, the cam gear 73 is still rotating with the first gear portion 73a meshing with the exit gear 37. Therefore, when the cam gear 73 rotates, the lock gear 74 is pushed in the rotation direction via the torsion spring 79. At this time, the lock lever 88 has moved to the engagement position. Therefore, the lock gear 74 rotates until the second lock claw 83 comes into contact with the lock lever 88 and is stopped.

6D and 7A, when the subsequent cam gear 73 rotates, the first gear portion 73a also moves away from the exit gear 37. At this time, the corner of the long diameter surface 91 b exceeds the contact portion 28 d of the second lever 28. Therefore, the cam 91 and the cam gear 73 are rotated until the dead center of the cam 91 is reached and the long diameter surface 91b comes into contact with the cam contact portion 28d by the elastic force of the coil spring 29. The lock gear 74 is stopped by a lock lever 88.
Therefore, as shown in FIG. 7A, the driven roll 22 is held in a state of being separated from the drive roll 21 in a state where the long diameter surface 91 b is in contact with the cam contact portion 28 d.

  7A-7D, when the solenoid 87 is turned on from the state shown in FIG. 7A, the lock gear 74 and the cam gear 73 are sequentially rotated to the initial position shown in FIG. 6A as in the case of FIGS. 6B-6D. Return. That is, the driven roll 22 returns to the state where it is in contact with the drive roll 21.

(Description of the control part of Example 1)
FIG. 8 is a block diagram illustrating the functions of the control unit of the image forming apparatus according to the first embodiment.
In FIG. 8, a controller C as an example of a control unit included in the copying machine U has an input / output interface I / O that performs input / output of signals to / from the outside. Further, the controller C has a read only memory (ROM) in which a program and information for performing necessary processing are stored. Further, the controller C has a random access memory (RAM) for temporarily storing necessary data. Further, the controller C includes a central processing unit (CPU) that performs processing according to a program stored in a ROM or the like. Therefore, the controller C of the first embodiment is configured by a small information processing apparatus, a so-called microcomputer. Therefore, the controller C can implement various functions by executing programs stored in the ROM or the like.

(Signal output element connected to controller C)
The controller C of the printer unit U1 receives output signals from signal output elements such as the user interface U0 and the sensors 16-18.
U0: User interface The user interface U0 includes a power button U01 as an example of a power-on unit, a display panel U02 as an example of a display unit, a start button U03 as an example of an input member for starting operation, and a numerical value input member As an example, a numeric keypad U04 and other input buttons (not shown) are provided.
The pre-registration sensor 16 detects the document Gi conveyed near the takeaway roll 3.
The registration sensor 17 detects the document Gi that has passed the document registration roll 4.
The discharge sensor 18 detects the original document Gi conveyed toward the exit roll 8.

(Controlled element connected to controller C)
The controller C is connected to a drive circuit D1 of a drive source, a drive circuit D2 of an auto feeder, a solenoid drive circuit D3, a power supply circuit E, and other control elements (not shown). The controller C outputs those control signals to the circuits D1 to D3, E and the like.
D1: Driving circuit for driving source The driving circuit D1 for driving source drives a main motor M1 as an example of a driving source to thereby drive the photosensitive drum PR, the developer holding member of the developing device G, the transfer belt TB, and the fixing device. F heating roll Fh, transport roll Ra, etc. are driven to rotate.

D2: Auto Feeder Drive Circuit An auto feeder drive circuit D2, which is an example of a drive circuit of the document feeder, controls the drive of the motor unit M2 to rotate the rollers 1 to 8 of the auto feeder U3.
D3: Solenoid Drive Circuit A solenoid drive circuit D3 as an example of a contact / separation drive circuit controls the drive of the solenoid 87 to control the movement of the lock lever 88.

E: Power Supply Circuit The power supply circuit E includes a power supply circuit E1 for development, a power supply circuit E2 for charging, a power supply circuit E3 for transfer, and a power supply circuit E4 for fixing.
E1: Power supply circuit for development The power supply circuit E1 for development applies a development voltage to the developer holding member of the developing device G.
E2: Power Supply Circuit for Charging The power supply circuit E2 for charging applies a charging voltage to the charging roll CR.
E3: Power Supply Circuit for Transfer The power supply circuit E3 for transfer applies a transfer voltage to the transfer roll TR.
E4: Power Supply Circuit for Fixing The power supply circuit E4 for fixing supplies heating power to the heating member of the heating roll Fh of the fixing device F.

(Function of controller C)
The controller C has a function of executing a process according to an input signal from the signal output element and outputting a control signal to each control element. That is, the controller C has the following functions.
C1: Image formation control means The image formation control means C1 controls the reading of an image by the scanner unit U2, the driving of each member of the copying machine U, the application timing of each voltage, and the like. Execute.

C2: Drive Source Control Unit The drive source control unit C2 controls the drive of the main motor M1 via the drive source drive circuit D1, and controls the drive of the photosensitive drum PR and the like.
C3: Power Supply Circuit Control Unit The power supply circuit control unit C3 controls the power supply circuits E1 to E4 to control the voltage applied to each member and the power supplied to each member.

C4: Document Conveyance Control Unit The document conveyance control unit C4, which is an example of a discharge member control unit, controls the driving of the rolls 1 to 8 of the auto feeder U3 via the auto feeder drive circuit D2. The document transport control means C4 according to the first exemplary embodiment rotates the motor unit M2 in the normal direction when a job is started when reading one side of the document Gi based on an input to the user interface U0. Then, when the leading edge of the document Gi reaches the position of the pre-registration sensor 17, the document conveyance control means C4 once stops the motor unit M2 and moves the motor unit M2 in accordance with the timing of conveying the document Gi to the image reading position 6. Re-drive. Then, the document conveyance control means C4 stops the motor unit M2 when the job is completed.

  In addition, the document conveyance control unit C4 according to the first exemplary embodiment rotates the motor unit M2 in the forward direction when a job is started when reading both sides of the document Gi. Then, when the trailing edge of the document Gi is detected by the discharge sensor 18, the document conveyance control means C4 rotates the motor unit M2 in the reverse direction. Accordingly, the document Gi is conveyed to the reversing path 11 with the conveyance direction reversed in the front-rear direction. Further, the document conveyance control means C4 changes the motor unit M2 from reverse rotation to normal rotation when the document Gi conveyed on the reversing path 11 is detected by the pre-registration sensor 16 and the document Gi reaches the takeaway roll 3. In the first exemplary embodiment, in the case of duplex reading, the document transport control unit C4 further inverts the document Gi after the duplex reading so that the order of the documents stacked on the document discharge tray TG2 does not change. Transport to path 11. That is, in total, the inversion path 11 is passed twice and the image reading position 6 is passed three times.

C5: Contact / Separation Control Unit The contact / separation control unit C5 includes an initial position return unit C5A, a reading control unit C5B, and a timer TM, and a lock lever 88 via a solenoid 87. The contact and separation between the drive roll 21 and the driven roll 22 are controlled.
C5A: Initial position return means The initial position return means C5A includes a power-on determination means C5A1 as an example of a return timing determination means and a first time storage means as an example of a first rotation amount storage means. C5A2, second time storage means C5A3 as an example of second rotation amount storage means, and third time storage means C5A4 as an example of third rotation amount storage means. Then, the initial position return means C5A according to the first embodiment returns the position of the elevating gear 71 to the preset initial position. In the first embodiment, the initial position is set to the position of the elevating gear 71 where the lock lever 88 contacts the first lock claw 82 and the drive roll 21 contacts the driven roll 22.

C5A1: Power-on discriminating means The power-on discriminating means C5A1 discriminates whether or not the power is turned on as an example of the return timing to the initial position. The power-on discriminating means C5A1 according to the first embodiment determines whether or not the power is on based on the power-on flag FL1 that is initialized to “0”.
C5A2: First Time Storage Unit The first time storage unit C5A2 has a first time t1 corresponding to the first rotation amount from the long diameter surface 91b to the short diameter surface 91a with respect to the rotation direction of the elevating gear 71. Remember. In the first embodiment, the first rotation amount is set to 3/4 rotation, that is, 270 degrees. Therefore, the first time t1 is set to a time for the lifting gear 71 to rotate 3/4.

C5A3: Second Time Storage Unit The second time storage unit C5A3 has a second time t2 corresponding to the second rotation amount from the short diameter surface 91a to the long diameter surface 91b with respect to the rotation direction of the elevating gear 71. Remember. In the first embodiment, the second rotation amount is set to 1/2 rotation, that is, 180 degrees. Therefore, the second time t2 is set to a time during which the elevating gear 71 rotates 1/2.
C5A4: Third Time Storage Unit The third time storage unit C5A4 corresponds to the third rotation amount obtained by subtracting the second rotation amount from the rotation amount for one rotation with respect to the rotation direction of the elevating gear 71. The third time t3 is stored. In the first embodiment, the third rotation amount is set to 1/2 rotation, that is, 180 degrees. Therefore, the third time t3 is set to a time during which the elevating gear 71 rotates 1/2.

  The initial position return means C5A according to the first embodiment turns the solenoid 87 off and moves the lock lever 88 to an engagement position where the lock lever 88 can come into contact with the lock claws 82 and 83 when the power is turned on. When the first time t1 elapses, the solenoid 87 is turned on, and the lock lever 88 is moved to the release position where it is released from the lock claws 82 and 83. When the second time t2 elapses, the solenoid 87 is turned off and moved to the engagement position. Then, when the third time t3 has elapsed, the return operation to the initial position is terminated.

C5B: Control Unit During Reading The control unit C5B during reading includes a separation time determination unit C5B1, a separation time storage unit C5B2, a contact time determination unit C5B3, and a contact time storage unit C5B4. When the image of the document Gi is read, the contact and separation between the drive roll 21 and the driven roll 22 are controlled.
C5B1: Separation Time Determination Unit The separation time determination unit C5B1 determines whether it is time to separate the drive roll 21 and the driven roll 22 from each other. The separation timing determination unit C5B1 according to the first embodiment determines that it is time to separate the motor unit M2 when the motor unit M2 shifts from reverse rotation to forward rotation during the double-sided reading operation.

C5B2: Separation Time Storage Unit The separation time storage unit C5B2 stores a separation time t4 that is a time to turn on the solenoid 87 when the drive roll 21 and the driven roll 22 are separated. In the first embodiment, the separation time t4 is such that the first lock claw 82 passes through the position of the lock lever 88 and the second lock claw 83 reaches the position of the lock lever 88 as the elevating gear 71 rotates. The time in the previous range is preset.

C5B3: Contact Timing Determination Unit The contact timing determination unit C5B3 determines whether it is time to contact the drive roll 21 and the driven roll 22 with each other. The contact timing determination unit C5B3 according to the first exemplary embodiment determines that it is time to contact when the discharge sensor 18 detects the front end of the document Gi in a state where the drive roll 21 and the heavy path roll 22 are separated from each other.
C5B4: Contact Time Storage Unit The contact time storage unit C5B4 stores a contact time t5 that is a time to turn on the solenoid 87 when the drive roll 21 and the driven roll 22 are brought into contact with each other. In the first embodiment, the contact time t5 is such that the second lock claw 83 passes through the position of the lock lever 88 and the first lock claw 82 reaches the position of the lock lever 88 as the elevating gear 71 rotates. The time in the previous range is preset.
TM: Timer The timer TM as an example of the time measuring means measures the times t1 to t5.

(Explanation of flowchart of Example 1)
Next, a control flow in the copying machine U according to the first embodiment will be described with reference to a flowchart, a so-called flowchart.
(Explanation of flowchart of contact / separation processing of exit roll of embodiment 1)
FIG. 9 is an explanatory diagram of a flowchart of the exit roll contact / separation process according to the first embodiment.
9 is performed in accordance with a program stored in the controller C of the copying machine U. This process is executed in parallel with other various processes of the copying machine U.

The flowchart shown in FIG. 9 is started when the copying machine U is turned on.
In ST1 of FIG. 9, it is determined whether or not the power-on flag FL1 is “0”. If yes (Y), the process proceeds to ST2. If no (N), the process proceeds to ST9.
In ST2, the following processes (1) and (2) are executed, and the process proceeds to ST3.
(1) Start normal rotation of the motor unit M2. At this time, the solenoid 87 is held in an OFF state.
(2) The first time t1 is set in the timer TM.

In ST3, it is determined whether or not the timer TM has expired. That is, it is determined whether or not the first time t1 has elapsed. If yes (Y), the process proceeds to ST4. If no (N), ST3 is repeated.
In ST4, the following processes (1) and (2) are executed, and the process proceeds to ST5.
(1) The solenoid 87 is turned on.
(2) The second time t2 is set in the timer TM.
In ST5, it is determined whether or not the timer TM has expired. That is, it is determined whether or not the second time t2 has elapsed. If yes (Y), the process proceeds to ST6, and if no (N), ST5 is repeated.

In ST6, the following processes (1) and (2) are executed, and the process proceeds to ST7.
(1) The solenoid 87 is turned off.
(2) The third time t3 is set in the timer TM.
In ST7, it is determined whether or not the timer TM has expired. That is, it is determined whether or not the third time t3 has elapsed. If yes (Y), the process proceeds to ST8, and if no (N), ST7 is repeated.
In ST8, the following processes (1) and (2) are executed, and the process proceeds to ST9.
(1) Stop the motor unit M2.
(2) Set the power-on flag FL = “1”.

In ST9, it is determined whether or not the job is started. If yes (Y), the process proceeds to ST10, and if no (N), ST9 is repeated.
In ST10, based on the input to the user interface U0, it is determined whether or not double-sided reading of the document Gi is performed. If no (N), the process proceeds to ST11, and if yes (Y), the process proceeds to ST12.
In ST11, it is determined whether or not the job is finished. If yes (Y), the process returns to ST1, and if no (N), ST11 is repeated.
In ST12, it is determined whether or not the motor unit M2 has started reverse rotation. If yes (Y), the process proceeds to ST13, and if no (N), ST12 is repeated.

In ST13, it is determined whether or not the motor unit M2 has started forward rotation. If yes (Y), the process proceeds to ST14, and if no (N), ST13 is repeated.
In ST14, the following processes (1) and (2) are executed, and the process proceeds to ST15.
(1) The solenoid 87 is turned on.
(2) The separation time t4 is set in the timer TM, and the time measurement of the separation time t4 is started.
In ST15, it is determined whether or not the timer TM has expired. That is, it is determined whether or not the separation time t4 has elapsed. If yes (Y), the process proceeds to ST16, and if no (N), ST15 is repeated.

In ST16, the solenoid 87 is turned off. Then, the process proceeds to ST17.
In ST17, it is determined whether or not the discharge sensor 18 is turned on. That is, it is determined whether or not the front edge of the document Gi has been detected. If yes (Y), the process proceeds to ST18, and if no (N), ST17 is repeated.
In ST18, the following processes (1) and (2) are executed, and the process proceeds to ST19.
(1) The solenoid 87 is turned on.
(2) The contact time t5 is set in the timer TM, and time measurement of the contact time t5 is started.

In ST19, it is determined whether or not the timer TM has expired. That is, it is determined whether or not the contact time t5 has elapsed. If yes (Y), the process proceeds to ST20. If no (N), ST19 is repeated.
In ST20, the solenoid 87 is turned off. Then, the process proceeds to ST21.
In ST21, it is determined whether or not the job is finished. If no (N), the process returns to ST12. If yes (Y), the process returns to ST1.

(Function of auto feeder U3)
In the auto feeder U3 according to the first embodiment having the above-described configuration, the motor unit M2 rotates forward when the paper feeding time comes. Along with this, the nudger roll 1 takes out the document Gi stored in the document tray TG1. The document separating roll 2 separates the documents Gi taken out by the nudger roll 1 one by one. The takeaway roll 3 conveys the original document Gi separated by the original separation roll 2 one by one. The document registration roll 4 sends the document Gi toward the image reading position 6 on the downstream side in time. The out-roll 7 conveys the document Gi whose image has been read at the image reading position 6 to the downstream side.

At the time of single-sided reading, the exit roll 8 conveys the document Gi toward the document discharge tray TG2.
During double-sided reading, when the downstream end in the transport direction passes through the discharge sensor 18, the motor unit M2 rotates in the reverse direction. Accordingly, the document Gi is transported toward the document reversing path 11 with the transport direction reversed in the front-rear direction. The document Gi that has passed through the document reversing path 11 is conveyed again to the takeaway roll 3.

  When the document Gi is conveyed to the takeaway roll 3, the motor unit M2 shifts from reverse rotation to normal rotation. At this time, the solenoid 87 is activated, and the drive roll 21 and the driven roll 22 of the exit roll 8 are separated from each other through the states shown in FIGS. 6A to 6D and 7A. Therefore, when the motor unit M2 rotates forward, the document Gi is pulled by the exit roll 8 and the takeaway roll 3, but in the first embodiment, the drive roll 21 and the driven roll 22 of the exit roll 8 are separated from each other. . Therefore, the document Gi is prevented from being pulled by the exit roll 8 and the takeaway roll 3.

When the motor unit M2 starts normal rotation, the takeaway roll 3, the document registration roll 4, the out roll 7, and the exit roll 8 start normal rotation. Then, the document Gi conveyed by the takeaway roll 3 or the like passes through the image reading position 6 in a state where the front and back are reversed. Therefore, the image on the second surface is read.
6C and 6D, when the front end of the document Gi from which the image on the second surface has been read passes through the discharge sensor 18, the solenoid 87 is activated. Therefore, the drive roll 21 and the driven roll 22 come into contact with each other through the states shown in FIGS. 7A to 7D and 6A. Therefore, the document Gi that has reached the exit roll 8 is conveyed by the exit roll 8.

  Here, document jam may occur in the auto feeder U3. When the user removes the jammed document, the elevating gear 71 may rotate due to the user touching the finger. When the operation of removing the jammed document is performed with the power turned off, the lifting gear 71 cannot be controlled to apply a brake or the like, and it is difficult to detect whether the lifting gear has rotated. If the rotational position of the elevating gear 71 is unknown, there is a possibility that the drive roll 21 and the driven roll 22 cannot be contacted or separated from each other, or the contact and separation are switched. Therefore, in the conventional configuration, the rotational position is returned to the preset initial position using a sensor that detects the rotational position of the elevating gear. However, when the sensor is used, there is a problem that the manufacturing cost increases.

FIG. 10 is an explanatory diagram of the operation of returning the lifting gear to the initial position according to the first embodiment, and FIG. 10A is an explanatory diagram when the lock lever is positioned downstream of the first lock claw when the power is turned on. 10B is an explanatory diagram when the lock lever is positioned upstream of the second lock claw when the power is turned on, and FIG. 10C is a diagram illustrating when the lock lever is located upstream of the first lock claw and the second lock claw when the power is turned on. It is explanatory drawing in the case of being located in the downstream.
On the other hand, in the elevating gear 71 of the first embodiment, when the power is turned on, the processes of ST2 to ST8 are performed to return to the initial position. For example, when the lock lever 88 is positioned at the position (i) in FIG. 10A, the lock lever 88 is moved to the position (ii) in the processes of ST2 and ST3. And it moves to the position of (iii) by processing of ST4 and ST5. And it moves to the position of (iv) by the process of ST6 and ST7. Similarly, even if the lock lever 88 is located at the position (i) in FIG. 10B or the position (i) in FIG. 10C, the process moves to the position (iv), that is, the initial position, in ST2 to ST8.

  Therefore, in the first embodiment in which the process of returning to the initial position is performed, it is possible to reliably return to the initial position without arranging a sensor that detects the rotational position of the elevating gear 71. Therefore, compared with the conventional structure which uses a sensor, in Example 1, it is possible to suppress manufacturing cost.

(Example of change)
As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the said Example, A various change is made in the range of the summary of this invention described in the claim. Is possible. Modification examples (H01) to (H07) of the present invention are exemplified below.
(H01) In each of the above-described embodiments, the copying machine U as an example of the image forming apparatus is illustrated. However, the present invention is not limited to this. . Further, the image forming apparatus is not limited to a single-color developing image forming apparatus, and may be constituted by a multicolor, so-called color image forming apparatus.
(H02) In the above-described embodiment, it is desirable that the original document Gi passes the reversing path 11 once after the second surface of the original document Gi is read. However, after reading the second surface, the original document Gi is conveyed to the reversing path 11. It is also possible to carry the original to the paper discharge tray TG2.

(H03) In the above-described embodiment, the configuration of the transmission system in which the document registration roll 4 and the out-roll 7 are also rotated reversely when the exit roll 8 is rotated reversely is exemplified, but the present invention is not limited thereto. For example, the driving of the document registration roll 4 and the out-roll 7 is not transmitted from the seventh intermediate gear 46 but from the eleventh intermediate gear 66, so that the document registration roll 4 and the out-roll 7 can take the take-away roll. As in the case of No. 3, the motor unit M2 can be continuously rotated in the same rotation direction regardless of forward and reverse rotation. In addition, it is desirable to drive all the rolls 1 to 8 with one motor unit M2. For example, only the exit roll 8 is driven with a motor capable of rotating forward and reverse, and the other rolls 1 to 7 are only forward rotated. It is also possible to adopt a configuration in which the motor is driven by another motor. Further, the number of transmission gears and the positional relationship are not limited to the illustrated configuration, and can be arbitrarily changed according to the design, specifications, etc., such as increase / decrease in the number of gears and change in position.

(H04) In the above-described embodiment, the installation positions of the sensors 16 to 18 and the control based thereon can be appropriately changed according to the design and specifications.
(H05) In the above embodiment, the configuration in which the angle formed by the first lock claw 32 and the second lock claw 33 is set to 90 degrees is exemplified, but the present invention is not limited to this. It is possible to set an arbitrary angle excluding 180 degrees according to the design and specifications. When the angle formed is changed, the gear portions 73a, 73b, 74a, 74b and the first to third rotation amounts are also changed to corresponding values.

(H06) In the above-described embodiment, a configuration in which a gear partially lacking teeth is used as the elevating gear 71 is not limited to this. For example, an arbitrary configuration that can switch between transmission and non-transmission of driving, such as combining an electromagnetic clutch and a gear, can be adopted.
(H07) In the above embodiment, the configuration in which the driven roll 22 is moved closer to and away from the drive roll 21 is exemplified, but the present invention is not limited to this. For example, the drive roll 21 may be configured to approach or separate from the driven roll 22. It is also possible to move both the drive roll 21 and the driven roll 22 in directions that approach and separate from each other.

8 ... conveying member,
21 ... Driving member,
22 ... driven member,
27-29 ... connecting member,
31-79 ... drive transmission system,
37. First gear member,
71 ... second gear member,
73a, 74a ... 1st gear part,
73b, 74b ... second gear part,
73c, 73d, 74c, 74d ... gap,
79 ... Rotational force applying member,
81: Stopped member,
82 ... first stopped portion,
83 ... the second stopped part,
86 ... Stopping member,
91. Actuating member,
91a ... 1st engaging part,
91b ... the second engaging portion,
C5: Contact / separation control means,
CCD: Imaging member,
Gi ... manuscript,
M2 ... drive source,
S ... medium
TG1 ... Document stacking section,
TG2: Document discharge section,
U: Image forming apparatus,
U1 ... Image recording device,
U2 ... Image reading device,
U3 ... Conveying device.

Claims (6)

A pair of conveying members;
A connecting member connected to one of the pair of transport members and relatively moving in a direction in which the pair of transport members are in contact with or separated from each other;
An operating member supported rotatably about a rotation axis, wherein the first engaging portion engages with the connecting member and contacts the pair of conveying members; and the first engaging portion And a second engaging portion that is disposed at a position whose phase is shifted by less than 180 degrees in the circumferential direction of the operating member, and engages with the connecting member to separate the pair of transport members. When,
A stopped member that is rotatably supported in conjunction with the actuating member, the first stopped portion disposed corresponding to the first engaging portion, and the second engaging portion. A second stopped portion correspondingly disposed, and the stopped member,
A stop member that engages with each of the stopped parts to stop the rotation of the stopped member, and engages with any of the stopped parts to hold the position of the operating member; The stop member movable between a release position where the engagement with each stopped portion is released, and
Contact / separation control means for controlling the stop member to control contact and separation of the pair of transport members, moving the stop member to the engagement position and moving the actuating member to the second engagement member. The first rotation amount is rotated along the rotation direction from the joint portion to the first engagement portion, and then the stop member is moved to the release position and the operating member is moved from the first engagement portion. A predetermined second rotation amount exceeding the rotation amount to the second engagement portion is rotated, and then the stop member is moved to the engagement position and the operation member is moved from the rotation amount for one rotation. The contact / separation control means for rotating the third rotation amount by subtracting the second rotation amount;
A conveying apparatus comprising: A first gear member to which driving is transmitted from a driving source, and a second gear formed integrally with the stopped member and supported so as to be movable coaxially and relatively with respect to the operating member A first gear portion that is formed on the outer periphery and transmits drive when meshed with the first gear member, and is disposed with a gap in the circumferential direction with respect to the first gear portion. And a second gear portion to which drive is transmitted when meshed with the first gear member, and the gap between the first gear portion and the second gear portion is the When each stopped portion engages with the stop member, the second gear member disposed at a position facing the first gear member , and a rotation direction set in advance on the second gear member A rotational force imparting member that imparts rotational force to the drive transmission system,
The transport apparatus according to claim 1, further comprising:   3. The pair of conveying members includes a driving member to which driving is transmitted, and a driven member that is disposed to face the driving member and that can be driven to rotate with a document interposed therebetween. The conveying apparatus as described. A document stacking unit on which the document is loaded;
A document discharge section for discharging the document;
A document transport path extending from the document stacking section through the document reading position to the document discharge section;
The pair of conveying members disposed in the document conveying path and conveying the document toward the document discharge section;
A reversing path that connects the upstream side of the pair of transport members and the upstream side of the document reading position with respect to the document transport direction, and transports the document to be read on the second side;
The transport apparatus according to claim 1, further comprising: An imaging member for reading an image of a document;
The conveyance device according to claim 1, wherein the imaging member conveys a document to a reading position where the document is read.
An image reading apparatus comprising: An image reading apparatus according to claim 5 for reading an image of a document;
An image recording apparatus for recording an image read by the image reading apparatus on a medium;
An image forming apparatus comprising:

Images