JP2014119587A - Holding mechanism of opening/closing member and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce force necessary for opening and closing an opening/closing member.SOLUTION: A holding mechanism of an opening/closing member (7 to 37) includes: an opening/closing member (U4) that is openably/closably supported with respect to a support (U1); holding members (27 to 37) that are rotatably supported by the support (U1); a pressing member (21) that is supported by the opening/closing member, and moves the holding members (27 to 37) to holding positions when the opening/closing member (U4) is closed; a grip part (7) that can be gripped and rotated by an operator; and a holding target member (18) that is supported by the opening/closing member (U4), can be rotated in conjunction with the movement of the grip part (7), and can be rotated, while the opening/closing member (U4) is closed, between a holding target position of being held by the holding members (27 to 37) that have moved to the holding positions and a separation position of being separated from the holding members (27 to 37).

Description

  The present invention relates to an opening / closing member holding mechanism and an image forming apparatus.

  In a conventional image forming apparatus, a technique described in Patent Document 1 below is conventionally known as a technique related to a holding mechanism for an opening / closing member.

  Japanese Patent Application Laid-Open No. 11-3024 as Patent Document 1 describes a technique related to an open / close cover (1) of a paper cassette (5). In the technique described in Patent Document 1, the paper cassette (5) is disposed close to the opening / closing cover (1) with the abutting portion (6) with respect to the rotation center (1A) of the opening / closing cover (1), and The force required when opening the opening / closing cover (1) is reduced by separating the hook member (3) holding the opening / closing cover (1) from the rotation center (1A). The hook member (3) described in Patent Document 1 is pulled by a spring (4). When the opening / closing cover (1) is opened and closed, the spring (4) is extended to rotate the hook member (3). With this, the lock is released.

Japanese Patent Laid-Open No. 11-3024 ("0031" to "0034", FIGS. 1 and 2)

  This invention makes it a technical subject to reduce force required when opening and closing an opening-and-closing member.

In order to solve the technical problem, the holding mechanism for the opening / closing member according to claim 1 is:
An opening and closing member supported to be openable and closable with respect to the support;
A holding member rotatably supported by the support body, the holding member being movable between a preset holding position and a retracted position rotated from the holding position;
A pressing member disposed corresponding to the holding member, wherein the pressing member moves the holding member to the holding position by pressing the holding member when the opening and closing member is closed;
A gripping part supported by the opening and closing member and gripped by an operator and rotatable;
A held member that is supported by the opening / closing member and that is arranged corresponding to the holding member and that can rotate in conjunction with the movement of the gripping portion, wherein the holding member is closed. The held member that is rotatable between a held position that is held in contact with the holding member moved to a position, and a disengaged position that is detached from the holding member with the movement of the gripping portion;
It is provided with.

According to a second aspect of the present invention, in the holding mechanism for the opening / closing member according to the first aspect,
A pressing portion that extends in a radial direction from the rotation center of the holding member and contacts the pressing member, wherein the pressing portion is disposed at a radially outer end portion of the pressing member;
It is provided with.

In order to solve the technical problem, an image forming apparatus according to claim 3 is provided.
The opening / closing member holding mechanism according to claim 1, further comprising the support body configured by a main body of the image forming apparatus.
It is provided with.

According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect,
The opening / closing member for opening / closing a conveyance path of a medium formed in a main body of the image forming apparatus;
It is provided with.

According to the first and third aspects of the invention, the force required to open and close the opening / closing member can be reduced as compared with the case where the configuration of the present invention is not provided.
According to the second aspect of the present invention, a stronger force can be applied to the holding member using the lever principle as compared with the case where there is no pushed portion extending in the radial direction from the rotation center.
According to the fourth aspect of the present invention, it is possible to reduce the force required when opening and closing the conveyance path.

FIG. 1 is an explanatory diagram of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is a perspective view of the opening / closing member on which the conveying member of Example 1 is supported. FIG. 3 is an explanatory diagram of the main body of the image forming apparatus in a state where the opening / closing member is opened. 4A and 4B are explanatory views of the holding mechanism according to the first embodiment, FIG. 4A is a perspective view, and FIG. 4B is an explanatory view in a state where a spring is removed from FIG. 4A. FIG. 5 is an explanatory diagram of a main part viewed from the direction of arrow V in FIG. 4B. 6A and 6B are explanatory views of the holding mechanism for the opening / closing member according to the first embodiment. FIG. 6A is an explanatory view showing a state in which the hook is moved to the holding position and the stud is moved to the detaching position. FIG. 6C is an explanatory view showing a state where the hook is moved to the retracted position and the stud is moved to the held position, and FIG. 6C is an explanatory view showing a state where the cover is further closed from the state shown in FIG. 6B.

Next, examples as specific examples of embodiments of the present invention will be described with reference to the drawings. However, 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 along the document transport path U3a between the document tray TG1 and the document discharge tray TG.

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 left side of the optical system A for reading, an imaging element CCD as an example of an imaging member is disposed. 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.

A photosensitive drum PR, which is an example of an image carrier, is disposed below the exposure apparatus ROS. The photosensitive drum PR rotates in the direction of the arrow Ya.
On the photosensitive drum PR, a charging roll CR, which is an example of a charger, is disposed opposite to the charging area Q0. A charging voltage is applied from the power supply circuit E to the charging roll CR. The power supply circuit E is controlled by a controller C as an example of a control unit. The controller C performs various controls by transmitting and receiving signals to and from the image processing unit GS and the writing circuit DL.
In the writing area Q1 set on the downstream side of the charging area Q0 with respect to the rotation direction of the photosensitive drum PR, a laser beam L as an example of writing light from the exposure device ROS is formed on the surface of the photosensitive drum PR. Is irradiated.
In the developing area Q2 set on the downstream side of the writing area Q1 with respect to the rotation direction of the photosensitive drum PR, the developing device G is disposed to face the surface of the photosensitive drum PR.

On the left side of the developing device G, a cartridge K as an example of a developer container is disposed. The cartridge K is detachably attached to a cartridge holder KS as an example of a container support member. Below the cartridge holder KS, a reserve tank RT as an example of a temporary storage portion for the developer is disposed. The reserve tank RT and the developing device G are connected by a developer transport device GH.
A transfer area Q3 is set on the downstream side of the development area Q2 with respect to the rotation direction of the photosensitive drum PR.

Under the printer unit U1, paper feed trays TR1 to TR4 as examples of a medium container are detachably supported. Sheets T as an example of a medium are accommodated in the sheet feed trays TR1 to TR4.
A pickup roll Rp as an example of a medium take-out member is disposed on the upper left side of the paper feed trays TR1 to TR4. On the left side of the pick-up roll Rp, a separating roll Rs as an example of a separating member is disposed.
On the left side of each of the paper feed trays TR1 to TR4, a medium transport path SH1 extending upward is formed. A plurality of transport rolls Ra as an example of a medium transport member are arranged in the transport path SH1.
A registration roll Rr as an example of a feeding member is disposed downstream of the conveyance roll Ra and upstream of the transfer region Q3 with respect to the conveyance direction of the sheet S.

  On the left side of the cartridge holder KS or the like, a manual feed tray TRt, which is an example of a medium storage container and serves as a manual feed portion, is installed. The manual feed tray TRt according to the first exemplary embodiment is supported to be rotatable about the rotation center TRt0. Therefore, the manual feed tray TRt is configured to be movable between a housed position shown by a solid line in FIG. 1 and a feedable position shown by a one-dot chain line in FIG. When the manual feed tray TRt according to the first embodiment is moved to the stored position, a part TRt1 of the manual feed tray TRt is accommodated in a state of entering the lower side of the cartridge holder KS and the left side of the reserve tank RT. . Accordingly, the entire copying machine U is reduced in capacity and reduced in size.

In the transfer area Q3, a transfer unit TU, which is an example of a transfer device and an example of a medium transport device, is disposed below the photosensitive drum PR. The transfer unit TU includes an endless transfer belt TB as an example of a medium transport member.
The transfer belt TB is rotatably supported by a driving roll Rd as an example of a driving member and a driven roll Rf as an example of a driven member.
Inside the transfer belt TB, a transfer roll TR as an example of a transfer device is supported. The transfer roll TR is disposed to face the photosensitive drum PR with the transfer belt TB interposed therebetween. Therefore, the transfer region Q3 is constituted by the region where the transfer roll TR and the photosensitive drum PR face each other. A transfer voltage is applied from the power supply circuit E to the transfer roll TR.

A peeling claw SC as an example of a medium peeling member is disposed at the right end of the transfer belt TB. Below the peeling claw SC, a belt cleaner CLb as an example of a cleaner of the transfer device is disposed to face the surface of the transfer belt TB.
Note that a drum cleaner CLp, which is an example of an image carrier cleaner, is disposed on the downstream side of the transfer region Q3 with respect to the rotation direction of the photosensitive drum PR so as to face the surface of the photosensitive drum PR. Yes.

A fixing device F is disposed on the right side of the transfer unit TU. The fixing device F includes a heating roll Fh as an example of a heating rotating member and a pressure roll Fp as an example of a pressing rotating member.
To the right of the fixing device F, a discharge path SH2 extending upward is connected as an example of a medium transport path.
In the discharge path SH2, as an example of a medium transport member, a transport roll Rb and a discharge roll Rh capable of transporting the medium and rotating in the forward and reverse directions are arranged.
On the upper surface of the printer unit U1, a paper discharge tray Rh as an example of a medium discharge unit is formed.

A reversing path SH3, which is an example of a medium transport path, is formed below the discharge path SH2. The reversing path SH3 according to the first embodiment branches from the discharge path SH2 and extends downward, and joins the transport path SH1 on the upstream side in the sheet transport direction from the registration roll Rr.
A gate MG as an example of a transfer direction switching member is disposed at a branch portion between the discharge path SH2 and the reversal path SH3. The gate MG of the first embodiment is formed of an elastically deformable thin film shape, so-called film. When the sheet S conveyed from the fixing device F passes through the gate MG, the gate MG is pushed by the sheet S and is elastically deformed so that the sheet S can pass through the discharge path SH2. When the sheet S is conveyed from the discharge path SH2 to the reversing path SH3, the gate MG is held in an elastically restored state, preventing the sheet S from entering the fixing device F, and the reversing path SH3. It arrange | positions so that the sheet | seat S may be guided to the side.

(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 document Gi passes through the optical system A and is collected 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 surface of the photosensitive drum PR is charged by the charging roll CR in the charging region Q0. At the latent image writing position Q1, the laser beam L output from the exposure apparatus ROS forms an electrostatic latent image on the surface of the photoconductor PR. In the developing region Q2, the developing device G develops the electrostatic latent image on the photosensitive drum PR that passes through the developing region Q2 into a toner image Tn as an example of a visible image. When the developer is consumed in the developing device G, the developer transport device GH is operated according to the consumption amount, and the developer is supplied from the cartridge K to the developing device G.

The sheets S of the respective trays TR1 to TR4 are taken out by the pickup roll Rp at a preset sheet feeding time. The sheets S picked up by the pickup roll Rp are separated one by one by the separating roll Rs when picked up in a state where a plurality of sheets S are overlapped. The sheet S that has passed the separating roll Rs is conveyed to the registration roll Rr by a plurality of conveyance rolls Ra.
The sheet S fed from the manual feed tray TRt also joins the transport path SH and is transported to the registration roll Rr.

The sheet S conveyed to the registration roll Rr is transferred from the sheet guide SG1 before transfer as an example of a guide member before transfer to the transfer area according to the timing when the toner image on the surface of the photosensitive drum PR moves to the transfer area Q3. It is transported toward Q3.
The sheet S conveyed from the registration roll Rr is supported on the surface of the transfer belt TB and passes through the transfer region Q3. The toner image Tn on the surface of the photosensitive drum PR is transferred to the sheet S passing through the transfer region Q3 by the transfer voltage applied to the transfer roll TR.
The surface of the photosensitive drum PR after passing through the transfer region Q3 is cleaned by removing residual toner by the drum cleaner CLp. The surface of the photosensitive drum PR after cleaning is recharged by the charging roll CR.

The sheet S to which the toner image Tn is transferred is peeled from the transfer belt TB by the peeling claw SC. From the transfer belt TB from which the sheet S has been peeled off, deposits such as developer and paper dust attached to the surface of the transfer belt TB are removed by the belt cleaner CLb. When the sheet S peeled from the transfer belt TB passes through the contact area between the heating roll Fh and the pressure roll Fp, the toner image is heated and pressed to be fixed.
The recording sheet S on which the toner image is fixed passes through the gate MG while being elastically deformed, and is conveyed to the discharge path SH2. The sheet S discharged to the paper discharge tray TRh is transported by the transport roll Rb and discharged to the paper discharge tray TRh by the discharge roll Rh.

  When duplex printing is performed, the trailing edge of the sheet S on which one side has been recorded is conveyed downstream by the conveyance roll Rb and the discharge roll Rh until it passes through the gate MG. When the trailing edge of the sheet S passes through the gate MG, the transport roll Rb and the discharge roll Rh rotate in the reverse direction and are transported from the discharge path SH2 toward the reversal path SH3. That is, the sheet S is so-called switched back with the conveyance direction reversed. The switched sheet S is guided by the gate MG and conveyed through the reversing path SH3. The sheet S conveyed on the reversing path SH3 joins the conveying path SH1, and is conveyed to the registration roll Rr with the front and back sides reversed. Then, an image is printed on the second surface of the sheet S in the transfer region Q3.

(Description of the opening / closing member of Example 1)
FIG. 2 is a perspective view of the opening / closing member on which the conveying member of Example 1 is supported.
FIG. 3 is an explanatory diagram of the main body of the image forming apparatus in a state where the opening / closing member is opened.
1 and 2, an opening / closing cover U4 as an example of an opening / closing member of Example 1 is a printer unit as an example of a support body and an example of a main body of an image forming apparatus with a rotation center U4a at the rear end as a center. U1 is rotatably supported.
The open / close cover U4 supports a driven roller 1 as an example of a driven member. The driven roller 1 is supported so as to be rotatable about the rotation shaft 1a. The driven roller 1 is disposed to face a driving roller 2 as an example of a driving member. The drive roller 2 is supported by the printer unit U1. The rotating shaft 1a of the driven roller 1 is pressed against the driving roller 2 when the opening / closing cover U4 is closed by a biasing member (not shown). The drive roller 2 is driven by a motor (not shown) as an example of a drive source.
The driven roller 1 and the driving roller 2 constitute a conveyance roller Ra of the first embodiment.

4A and 4B are explanatory views of the holding mechanism according to the first embodiment, FIG. 4A is a perspective view, and FIG. 4B is an explanatory view in a state where a spring is removed from FIG. 4A.
In FIG. 2, an opening 6 is formed at the front of the opening / closing cover U4. A handle 7 as an example of a gripping member is disposed on the front side of the opening 6. A stopper 7 a as an example of a stop member is formed on the front surface of the handle 7. The stopper 7 a extends forward from the front end of the opening 6. On the upper surface of the handle 7, a protrusion 7 b is formed as an example of a support portion for the urging member.
A shaft 8 as an example of a shaft portion is supported on the front portion of the handle 7. The shaft 8 is formed in a bar shape extending in the vertical direction. An upper end portion and a lower portion of the shaft 8 are rotatably supported by the opening / closing cover U4 by the bearing portion 9. Therefore, the handle 7 is rotatably supported with respect to the opening / closing cover U4.

The shaft 8 is provided with a torsion spring 11 as an example of an urging member. The torsion spring 11 according to the first embodiment has one end supported by the protrusion 7b and the other end supported by the inner surface of the opening / closing cover U4. Therefore, the torsion spring 11 pushes the handle 7 in a direction in which the stopper 7a contacts the inner surface of the opening / closing cover U4.
Therefore, the handle 7 is held in a state where the torsion spring 11 presses the handle 7 and the stopper 7a is in contact with the inner surface of the opening / closing cover U4 when the user is not applying force.

A hanging portion 16 as an example of a member to be held is supported at the lower end of the shaft 8. The hanging portion 16 according to the first exemplary embodiment is disposed at the front end that is outside the region through which the recording sheet S passes. That is, the hanging portion 16 is arranged at a position that does not prevent the recording sheet S from passing.
The hanging portion 16 includes a hanging portion frame 17 as an example of a frame. The frame 17 of the hanging portion of the first embodiment has a vertical plate portion 17a. The vertical plate portion 17a is formed in a plate shape extending in the vertical direction. The vertical plate portion 17 a is fixed to the lower end of the shaft 8. An upper wall 17b and a lower wall 17c are formed at the upper and lower ends of the vertical plate portion 17a. Therefore, the frame 17 of the hanging portion of the first embodiment is formed in a U shape.

  A stud 18 as an example of a main body of the member to be held is supported between the upper wall 17b and the lower wall 17c. The stud 18 of the first embodiment is formed in a bar shape extending in the vertical direction. Behind the stud 18 is formed a spring support portion 19 as an example of a support portion for a pressing member. The spring support portion 19 is disposed at a rearward interval with respect to the stud 18. The spring support portion 19 supports a coil spring 21 as an example of a pressing member.

FIG. 5 is an explanatory diagram of a main part viewed from the direction of arrow V in FIG. 4B.
In FIG. 4, a support plate 26 as an example of a support portion of a holding member is fixedly supported at a position corresponding to the hanging portion 16 in the printer unit U1. A lever 27 as an example of a pushed member is supported on the upper surface of the support plate 26. The lever 27 of the first embodiment is formed in a plate shape extending in the front-rear direction. The lever 27 is rotatably supported by the support plate 26 around the rotation center 27a. The rotation center 27a of the lever 27 according to the first embodiment is set on the front side of the center portion of the lever 27 in the front-rear direction. Further, a contact surface 27b as an example of a pressed portion is formed on the left surface of the rear end portion of the lever 27. The contact surface 27b is supported so that the free end of the coil spring 21 can be contacted and separated. Therefore, the contact surface 27b of the lever 27 is disposed at a position separated rearward in the radial direction with respect to the rotation center 27a.
In FIG. 5, a convex portion 27 c as an example of a stop portion is formed at the front end portion of the lower surface of the lever 27. The convex part 27c of Example 1 is formed in the convex shape which protrudes below.

  A hook 31 as an example of a main body of the holding member is supported on the front end portion of the lever 27. The hook 31 according to the first embodiment is disposed at a position corresponding to the stud 18. The hook 31 has a column part 32 as an example of a supported part. The column part 32 is rotatably supported by the lever 27. A stopper 32a, which is an example of a stopped portion, is supported at the lower end of the column portion 32 at a position corresponding to the convex portion 27c. Therefore, the hook 31 stops rotating when the stopper 32a comes into contact with the convex portion 27c. In the first embodiment, when the stopper 32a comes into contact with the convex portion 27c, the positions of the stopper 32a and the convex portion 27c so that the hook 31 is held at the rotational position extending leftward as shown in FIG. 4A. Is set.

4 and 5, a base end portion 33 is supported on the upper end of the column portion 32. The base end portion 33 is formed in a plate shape extending in the front-rear direction. In FIG. 5, a protrusion 33 a as an example of a stopping portion of the urging member is formed on the lower surface of the base end portion 33.
A front end portion 34 is formed at the front end of the base end portion 33. The front end portion 34 is formed in a plate shape extending leftward.
A claw portion 36 is formed at the left end of the front end portion 34. The claw portion 36 extends rearward corresponding to the stud 18. A holding surface 36 a as an example of a holding portion is formed on the right surface of the claw portion 36. The holding surface 36 a is configured to be able to contact the stud 18.
In addition, a guide surface 36 b as an example of a guide portion is formed on the left surface of the claw portion 36. The guide surface 36b is inclined backward as it goes to the right.
Therefore, the hook 31 is formed in a bowl shape extending toward the stud 18.

A torsion spring 37 as an example of a return member is supported on the column portion 32. One end of the torsion spring 37 is supported by the upper end of the rotation center 27 a of the lever 27. The other end of the torsion spring 37 is in contact with the protrusion 33a. The torsion spring 37 applies a force in the direction in which the hook 31 is rotated in the direction in which the stopper 32a contacts the recess 27c.
The lever 27, the hook 31 and the torsion spring 37 constitute holding members 27 to 37 of the first embodiment.

In the first embodiment, the torsion springs 11 and 37 apply a force necessary to return the handle 7 and the hook 31 to the positions where the stoppers 7a and 32a come into contact. On the other hand, the coil spring 21 applies a force necessary for locking so as to hold the hook 31 in contact with the stud 18. That is, the coil spring 21 is set so that a force is applied to prevent the opening / closing cover U4 from opening even when the opening / closing cover U4 is closed and the driven roller 1 receives a reaction force from the driving roller 2. Therefore, in the first embodiment, the torsion springs 11 and 37 are set to have a smaller elastic force than the elastic force of the coil spring 21.
The members denoted by reference numerals 7 to 37 constitute the opening / closing member holding mechanisms 7 to 37 of the first embodiment.

(Function of holding mechanism for opening / closing member)
In the copying machine U of the first embodiment having the above-described configuration, the stud 18 is held at the held position shown in FIG. 4A by the elastic force of the torsion spring 11 when the opening / closing cover U4 is closed. At this time, the lever 27 moves to the pushed position shown in FIG. 4A, with the contact surface 27b pushed by the coil spring 21. At this time, the hook 31 rotatably supported by the lever 27 is held at the holding position shown in FIG. 4A by the elastic force of the torsion spring 37.
Therefore, in the state shown in FIG. 4A, the coil spring 21 applies a force in the direction in which the hook 31 is applied to the stud 18. The stud 18 comes into contact with the holding surface 36a of the hook 31, and the opening / closing cover U4 is held in a closed state. Even when the follower roll 1 receives the force that the open / close cover U4 is to be opened by the force received from the drive roll 2, the elastic force of the coil spring 21 holds the hook 31 on the stud 18. .

6A and 6B are explanatory views of the holding mechanism for the opening / closing member according to the first embodiment. FIG. 6A is an explanatory view showing a state in which the hook is moved to the holding position and the stud is moved to the detaching position. FIG. 6C is an explanatory view showing a state where the hook is moved to the retracted position and the stud is moved to the held position, and FIG. 6C is an explanatory view showing a state where the cover is further closed from the state shown in FIG. 6B.
When a paper jam occurs in the transport path SH1 and the opening / closing cover U4 is opened, the operator holds the handle 7 and the handle 7 is rotated. When the handle 7 is rotated, the stud 18 moves from the held position shown in FIG. 4A to the detached position shown in FIG. 6A. Therefore, the contact between the hook 31 and the stud 18, that is, the so-called lock is released, and the opening / closing cover U4 can be opened. Therefore, in the open / close cover U4 of the first embodiment, the coil spring 21 is not elastically deformed when the open / close cover U4 is opened. Therefore, the force required when the operator opens the opening / closing cover U4 is relatively weak in elastic force, and is a force that elastically deforms the coil spring 11 that only returns the handle 7 to the original position.

That is, in the conventional opening / closing cover as in the configuration described in Patent Document 1, when the hook is locked on the stud or the like by the force of an elastic member such as a spring, and the lock is released, it is opposite to the direction in which the lock is applied. Move the hook in the direction. Therefore, when the lock is released, it is necessary to move the hook by elastically deforming the elastic member that applies the force for hooking. However, when the elastic member is elastically deformed, the elastic force increases, and there is a problem that the operation force necessary for the operator to operate increases. Correspondingly, if the original elastic force of the elastic member is weakened, the lock of the open / close cover becomes insufficient and the open / close cover may be opened.
In contrast, in the first embodiment, when the handle 7 is rotated, the coil spring 21 that applies the force in the direction in which the hook 31 is applied is not elastically deformed. Therefore, the operating force is reduced in the holding mechanisms 7 to 37 of the first embodiment as compared with the conventional configuration.

When the opening / closing cover U4 is closed from the opened state, the stud 18 is moved to the held position by the force of the coil spring 11 and the free end of the coil spring 21 is separated from the lever 27. At this time, the lever 27 and the hook 31 are free to rotate with respect to the printer unit U1 around the rotation center 27a. Therefore, when the opening / closing cover U4 is closed and the stud 18 comes into contact with the guide surface 36b of the hook 31, the lever 27 and the hook 31 move to the retracted position shown in FIG. 6B.
When the free end of the coil spring 21 comes into contact with the contact surface 27b of the lever 27, the lever 27 receives a force that rotates to the pushed position shown in FIG. 4A. In the first embodiment, the hook 31 is rotatably supported with respect to the lever 27 and is pressed by a torsion spring 37 that is weaker than the coil spring 21. Therefore, when the stud 18 is in contact with the guide surface 36 b and the free end of the coil spring 21 is in contact with the contact surface 27 b of the lever 27, the hook 31 is moved against the lever 27 when the opening / closing cover U 4 is further pressed. Then, as shown in FIG. 6C, it rotates relatively forward.

When the opening / closing cover U4 is further closed from the state shown in FIG. 6C and the stud 18 moves to the right of the guide surface 36b, it is pushed by the torsion spring 37, and the hook 31 is moved backward relative to the lever 27. Rotate to. The lever 27 is also pushed by the coil spring 21 and rotates. Therefore, as shown in FIG. 4A, the hook 31 moves to the holding position and is held in a state where the hook 18 is hooked on the stud 18.
Therefore, in Example 1, the coil spring 21 is hardly elastically deformed even when the open / close cover U4 is closed, and the torsion spring 37 having a weak elastic force is deformed. In the conventional configuration such as the technology described in Patent Document 1, when closing the open / close cover, when the hook is retracted, the spring that applies the force in the direction of hooking is elastically deformed in the direction of releasing the hook. It is necessary to let Therefore, a force for elastically deforming the spring is also required when closing the open / close cover. Compared to this conventional configuration, the configuration of the first embodiment requires almost no force for elastically deforming the coil spring 21, and the operating force is reduced.

  In the first embodiment, the coil spring 21 contacts the contact surface 27b away from the rotation center 27a of the lever 27. Therefore, the force of the coil spring 21 is amplified by the lever principle with respect to the hook 31 supported by the lever 27 closer to the rotation center 27a than the contact surface 27b. Therefore, compared with the case where the contact position with the lever 27 is close to the rotation center 27a, even if the elastic force of the coil spring 21 is weakened, the hook 31 is pushed with a preset force and the stud 18 is held by the hook 31. It is possible. Therefore, when a configuration having a weak elastic force is used as the coil spring 21, the force with which the coil spring 21 pushes the lever 27 is weakened when the opening / closing cover U4 is opened / closed. Therefore, it can be expected that the operating force is further reduced.

(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 (H09) of the present invention are exemplified below.
(H01) In each of the above embodiments, the copying machine U is illustrated as an example of the image forming apparatus, but the present invention is not limited to this. For example, the present invention can be applied to a printer as an example of an image forming apparatus, a FAX, or a multifunction machine having a plurality of these functions. Further, the present invention is not limited to a single color image forming apparatus, and can be applied to a multicolor image forming apparatus.

(H02) In the above-described embodiment, the configuration in which the hook 31 is rotatably supported with respect to the lever 27 is illustrated, but the present invention is not limited to this. For example, the hook 31 can be fixedly supported with respect to the lever 27, or the hook 31 and the lever 27 can be integrally formed. In this case, the torsion spring 37 and the protrusion 33a are not necessary. In this configuration, when the cover U4 is closed from the state shown in FIG. 6B, the torsion spring 37 is elastically deformed in the first embodiment. However, when the hook 31 is fixedly supported on the lever 27, the state shown in FIG. When the cover U4 is closed, the coil spring 21 is elastically deformed.
(H03) In the above embodiment, the coil spring 21 is exemplified as a member for applying a pressing force, but the present invention is not limited to this. For example, the configuration can be changed to any configuration that applies a pressing force such as a leaf spring, rubber, or a torsion spring. Similarly, the torsion springs 11 and 37 can be changed to coil springs, rubbers, leaf springs, or the like.

(H04) In the said Example, it is not limited to the structure which supports the follower roll 1 in the opening / closing cover U4. It is also possible to adopt a configuration in which the driving roll 2 is supported by the opening / closing cover U4.
(H05) In the above-described embodiment, the cover that opens and closes the transport path SH1 is illustrated as the opening and closing cover U4. However, the present invention is not limited to this. Therefore, it is applicable to any cover that opens and closes when the handle is unlocked, such as a cover that opens and closes a conveyance path other than the conveyance path SH1 and a cover that opens and closes when a unit that can be attached to and detached from the image forming apparatus is replaced. Is possible. Further, the present invention is not limited to the cover of the image forming apparatus, and can be applied to an arbitrary opening / closing member that unlocks with a handle such as a door of a car, a door of a locker, a door of a house, a desk drawer, or the like.

(H06) In the above-described embodiment, it is desirable to employ a configuration using the lever principle by using the plate-like lever 27, but the present invention is not limited to this. For example, the coil spring 21 may be configured to push the proximal end portion 33 of the hook 31.
(H07) In the above-described embodiment, the configuration in which both the stud 18 and the coil spring 21 are disposed in the front lower portion of the cover is illustrated, but the present invention is not limited to this. In other words, the stud 18 and the coil spring 21 can be disposed apart from each other. At this time, the positions and shapes of the hook 31 and the lever 27 can be changed in accordance with the positions of the stud 18 and the coil spring 21. That is, design, specifications, etc., such as lengthening the lever 27, changing the position of the rotation center 27a, extending the column portion 32 in the vertical direction, and increasing the length of the base end portion 33 and the front end portion 34, etc. It is possible to change arbitrarily according to.

(H08) In the above-described embodiment, the configuration in which the torsion springs 11 and 37 are provided to return the handle 7 and the hook 31 to the preset positions where the stoppers 7a and 32a come into contact is illustrated, but the present invention is not limited to this. For example, when adopting a configuration that naturally returns to a preset position by the balance of the center of gravity of the handle 7 or the hook 31, the torsion springs 11 and 37 can be omitted.
(H09) In the above-described embodiment, the configuration in which the free end of the coil spring 21 is in direct contact with the lever 27 is exemplified, but the present invention is not limited to this. For example, a member such as a plate-like cap may be supported on the free end side of the coil spring 21 so that the contact with the lever 27 can be easily stabilized. Moreover, the coil spring 21 is not limited to the structure arrange | positioned at the opening-and-closing cover U4 side. For example, one end is supported on the contact surface 27b side of the lever 27, and the other end of the coil spring 21 is separated from the inner surface of the cover U4 when the cover U4 is opened, and contacts the cover U4 when the cover U4 is closed. It is also possible to adopt a configuration in which a force applied by 31 is applied.

7: gripping part,
7 to 37: holding mechanism for the opening and closing member,
18 ... retained member,
21 ... Pressing member,
27 ... pressed member,
27-37 ... holding member,
27a ... the rotation center of the holding member,
S ... medium
SH1 ... transport path,
U: Image forming apparatus,
U1 ... main body and support of the image forming apparatus,
U4: Opening / closing member.

Claims (4)

An opening and closing member supported to be openable and closable with respect to the support;
A holding member rotatably supported by the support body, the holding member being movable between a preset holding position and a retracted position rotated from the holding position;
A pressing member disposed corresponding to the holding member, wherein the pressing member moves the holding member to the holding position by pressing the holding member when the opening and closing member is closed;
A gripping part supported by the opening and closing member and gripped by an operator and rotatable;
A held member that is supported by the opening / closing member and that is arranged corresponding to the holding member and that can rotate in conjunction with the movement of the gripping portion, wherein the holding member is closed. The held member that is rotatable between a held position that is held in contact with the holding member moved to a position, and a disengaged position that is detached from the holding member with the movement of the gripping portion;
A holding mechanism for the opening and closing member. A pressing portion that extends in a radial direction from the rotation center of the holding member and contacts the pressing member, wherein the pressing portion is disposed at a radially outer end portion of the pressing member;
The holding mechanism for the opening / closing member according to claim 1, comprising: The opening / closing member holding mechanism according to claim 1, further comprising the support body configured by a main body of the image forming apparatus.
An image forming apparatus comprising: The opening / closing member for opening / closing a conveyance path of a medium formed in a main body of the image forming apparatus;
The image forming apparatus according to claim 3, further comprising:

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