MEDIUM CONVEYANCE APPARATUS AND IMAGE FORMATION APPARATUS
A medium conveyance apparatus includes a conveyance mechanism to convey a medium along a main conveyance path from a front side to a rear side; a sub-conveyance unit including a sub-conveyance path parallel with the main conveyance path and configured to convey the medium along the sub-conveyance path from the rear side to the front side; a medium transport mechanism to transport the medium from the sub-conveyance path or the medium supply unit to the main conveyance path; and a support member supporting the sub-conveyance unit to be slidable toward the front side. The sub-conveyance unit includes: a plate member defining the sub-conveyance path; and a medium guide mechanism attached to one end of the plate member on the front side. The medium guide mechanism guides the medium from the medium supply unit to the medium transport mechanism, and the medium from the sub-conveyance path to the medium transport mechanism.
This application claims priority based on 35 USC 119 from prior Japanese Patent Application No. 2013-118049 filed on Jun. 4, 2013, entitled “MEDIUM CONVEYANCE APPARATUS AND IMAGE FORMATION APPARATUS”, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION1. Field of the Invention
This disclosure relates to a medium conveyance apparatus on which a medium conveyance unit for use to form images on both sides of a sheet-like medium is detachably mounted, and an image formation apparatus provided with the medium conveyance apparatus.
2. Description of Related Art
Some image formation apparatuses such as printers or copiers have a duplex printing function of forming images on both sides (front-side surface and back-side surface) of a sheet-like medium such as paper, in addition to a function of forming an image on one side thereof. For example, Patent Literature 1 (Japanese Patent Application Publication No. 2012-181387, FIG. 4 and paragraphs [0050] to [0052]) discloses an image formation apparatus having a duplex printing function.
In the image formation apparatus in Patent Literature 1, a conveyance unit (referred to as “duplex printing unit” in Patent Literature 1) is detachably attached to an apparatus main body in a slidable manner. After an image is formed on the front-side surface of a medium, the conveyance unit reverses the medium upside down in order to form an image on the back-side surface of the medium.
SUMMARY OF THE INVENTIONHowever, the conveyance unit cannot be easily detached from the apparatus main body.
An objective of one embodiment of the invention is to enable a conveyance unit to be easily dismounted.
An aspect of the invention is a medium conveyance apparatus for use in an image formation apparatus provided with: a main body including a front end and a rear end being opposed to each other, a medium supply unit disposed in the main body, and a process unit configured to process a medium conveyed along with a main conveyance path in the main body. The medium conveyance apparatus includes: a conveyance mechanism configured to convey the medium along with the main conveyance path from a front end side to a rear end side; a sub-conveyance unit including a sub-conveyance path provided in parallel with the main conveyance path, and configured to send out the medium processed in the process unit by conveying the medium along with the sub-conveyance path from the rear end side to the front end side; a medium transport mechanism configured to transport the medium sent out from either one of the sub-conveyance path and the medium supply unit to the main conveyance path; and a unit support member supporting the sub-conveyance unit such that the sub-conveyance unit is slidable to the front end side. The sub-conveyance unit includes: a plate member defining the sub-conveyance path; and a medium guide mechanism attached to one end of the plate member on the front end side. The medium guide mechanism guides the medium sent out from the medium supply unit to the medium transport mechanism, and the medium sent out from the sub-conveyance path to the medium transport mechanism.
According to the above aspect of the invention, the sub-conveyance unit can be easily dismounted together with the medium guide mechanism.
Descriptions are provided hereinbelow for embodiments based on the drawings. In the respective drawings referenced herein, the same constituents are designated by the same reference numerals and duplicate explanation concerning the same constituents is omitted. All of the drawings are provided to illustrate the respective examples only.
Hereinafter, various embodiments according to the invention are described with reference to the drawings.
Hereinafter, the same constituents are designated by the same reference numerals in all the drawings.
First EmbodimentApparatus main body 10 includes a front end (right side in the drawing) and a rear end (end disposed on the side opposite to the front end) that are opposed to each other. Image formation apparatus 1 is provided with a front surface cover on the front end side of apparatus main body 10, but
Medium house cassette 20 has a function of housing media Pa in a state of being accumulated on medium reception portion 21, and is detachably mounted to apparatus main body 10. One end of medium reception portion 21 is lifted upward by an elastic member (not illustrated). Recording medium Pa includes, for example, paper, synthetic paper, cardboard, specific paper, or a sheet-like medium such as a plastic film or cloth, but medium Pa is not limited thereto. A user can draw out medium storage cassette 20 in such a manner that the user grips handle portion 20h of medium storage cassette 20 to slide medium storage cassette 20 from apparatus main body 10 in the direction of the front end side thereof.
Pickup roller 32 is capable of picking up medium Pa from medium storage cassette 20 by rotating in the counterclockwise direction in response to a rotation driving force transmitted from a drive motor (not illustrated). Feed roller 33 is capable of sending out medium Pa from medium storage cassette 20 to medium guide mechanism 46 by rotating in the counterclockwise direction in response to the rotation driving force transmitted from a drive motor (not illustrated). Separation roller 23 that sends out medium Pa one by one from medium storage cassette 20 is disposed at a position opposed to feed roller 33. Even if two or more pieces of media Pa are picked up inadvertently at one time from medium storage cassette 20, separation roller 23 can separate the two or more media Pa into each medium Pa piece.
Medium guide mechanism 46 includes main guide member 47 and sub-guide member 48 as illustrated in
As illustrated in
A pair of conveyance rollers 81A, 81B as a conveyance mechanism are disposed downstream of medium transport mechanism 50 in the medium conveyance direction. Conveyance rollers 81A, 81B convey medium Pa transported onto main conveyance path D0 from medium transport mechanism 50 toward process unit 60.
Meanwhile, multi-purpose tray (MPT) 25 can be mounted on the front end of apparatus main body 10. For example, the user can manually feed sheet-like medium Pa in MPT 25. Image formation apparatus 1 is provided with pickup roller 26, feed roller 27, and separation roller 28 that are used for sending medium Pa in MPT 25 to main conveyance path D0. Pickup roller 26 rotates in the clockwise direction in response to the rotation driving force transmitted from the drive motor (not illustrated) to pick up medium Pa from MPT 25. Feed roller 27 rotates in the clockwise direction in response to the rotation driving force transmitted from the drive motor (not illustrated) to send out medium Pa to a region between upper registration roller 54 and upper pressurization roller 55 in medium transport mechanism 50. Separation roller 28 that sends out medium Pa, picked up from MPT 25 one by one, is disposed at the position opposed to feed roller 27. Upper registration roller 54 and upper pressurization roller 55 can transport medium Pa sent from MPT 25 to main conveyance path D0.
Image formation apparatus 1 is further provided with process unit 60 and fuser 70 that are disposed along with main conveyance path D0. Process unit 60 operates in response to a control by a control circuit (not illustrated), and has a function of forming a developer image corresponding to image data in accordance with an electrophotographic method. Transfer roller 69 is disposed at a position opposed to process unit 60. Transfer roller 69 is a member that causes the developer image formed on process unit 60 to be transferred onto medium Pa.
Process unit 60 includes, as illustrated in
LED head 65 is disposed at a position opposed to and near to the surface of photosensitive drum 62. LED head 65 irradiates the surface of photosensitive drum 62 with pattern light corresponding to an image to be printed to form an electrostatic latent image on photosensitive drum 62. Such an LED head 65 can be configured to include a large number of LED elements (light-emitting diode elements) that are arranged along in the longitudinal direction of photosensitive drum 62 (vertical direction in the drawing), an LED drive circuit that drives these LED elements, and an array of optical lenses that guides emission light from these LED elements to the surface of photosensitive drum 62.
When a portion of the surface of photosensitive drum 62, on which an electrostatic latent image is formed, reaches development roller 67, a developer is transferred to the electrostatic latent image due to a potential difference between the electrostatic latent image on photosensitive drum 62 and development roller 67. This causes a developer image (toner image) to be formed on photosensitive drum 62. Thereafter, the developer image on photosensitive drum 62 is conveyed to a position (transfer position) opposed to transfer roller 69. Herein, the developer image on photosensitive drum 62 is transferred onto the surface of medium Pa by a transfer bias applied to transfer roller 69. A cleaning device, not illustrated, removes the developer that is not transferred onto the surface of medium Pa but remains on photosensitive drum 62.
Fuser 70 has a function of fixing the developer image on medium Pa that is sent from process unit 60 onto medium Pa. As illustrated in
Conveyance rollers 82A, 82B send medium Pa—out from fuser 70 to the rear end side of the apparatus (at the downstream side in the medium conveyance direction on main conveyance path D0). In this case, medium Pa is fed to either one of discharge conveyance path D1 and switchback conveyance path D2 in accordance with the positions of separators 88, 89. When medium Pa is supplied to discharge conveyance path D1, discharge rollers 83A, 83B, 84A, and 84B discharge medium Pa onto a medium placement surface of stacker unit 11.
In contrast, when image formation apparatus 1 operates in a duplex printing mode, medium Pa is supplied to switchback conveyance path D2 in order to form a printed image on a back-side surface of medium Pa. When medium Pa is supplied to switchback conveyance path D2, conveyance roller 85A, 85B, 86A, and 86B convey medium Pa upward on switchback conveyance path D2. Thereafter, the position of separator 89 is switched. Then, conveyance roller 85A, 85B, 86A, and 86B rotate in the reverse direction to convey medium Pa downward in apparatus main body 10. In this case, separator 89 and conveyance rollers 87A, 87B guide medium Pa to sub-conveyance path D3 that is provided in parallel with main conveyance path DO. Sub-conveyance path D3 is a conveyance path provided in order to convey medium Pa with one side (front-side surface) on which a printed image is formed to the front end side of the apparatus.
Note that, switchback conveyance path D2, switchback conveyance rollers 85A, 85B, 86A, and 86B, and separators 88, 89 can constitute a reverse conveyance mechanism of the invention.
Referring to
As illustrated in
Sub-guide member 48 is fixed to a front end of guide plate member 41. An inner surface of sub-guide member 48 (inner guide surface 48a) guides medium Pa to the inlet-side end (region between lower registration roller 51 and lower pressurization roller 52) of medium transport mechanism 50. Further, an outer surface (outer guide surface 48b) of sub-guide member 48 is opposed to main guide member 47, and forms the clearance through which medium Pa sent from medium storage cassette 20 passes.
The front and back sides of medium Pa that is sent to medium transport mechanism 50 from sub-conveyance path D3 are reversed. In this case, medium transport mechanism 50 feeds medium Pa in a state where the front-side surface is directed downward and the back-side surface is directed upward to main conveyance path D0. This enables process unit 60, transfer roller 69, and fuser 70 to form a printed image on the back-side surface of medium Pa.
Tip part 47t of main guide member 47 in a use state illustrated in
As illustrated in
When medium Pa is conveyed in sub-conveyance path D3, medium Pa reaching sub-conveyance unit 40 is firstly carried on rear end 41b of guide plate member 41, then passes through a space between guide plate member 41 and guide frame 42, and thereafter, passes from front end 41f of guide plate member 41 over sub-guide member 48.
Side frames 43L, 43R extend in the X axis direction, and are shaped to be left-right symmetric to each other. As illustrated in
Moreover, as illustrated in
Engagement portions 47a, 47b are respectively formed at both ends in the transverse width direction (Y axis direction) of main guide member 47. Engagement portions 47a, 47b protrude from a main body unit of main guide member 47 to the sides thereof. As illustrated in
Next, a configuration of base unit 30 serving as a unit support member that supports sub-conveyance unit 40 is described in detail.
As illustrated in
Rail frames 36L, 36R have guide structures at inner surfaces thereof in which side frames 43L, 43R in sub-conveyance unit 40 illustrated in
Further, as illustrated in
Next, a configuration of medium transport mechanism 50 is described in detail.
As illustrated in
Lower registration roller 51 includes shaft portion 51s that is turnably supported by main frames 56L, 56R, and sub registration rollers 51A, 51B that commonly use shaft portion 51s. Moreover, lower pressurization roller 52 includes shaft portion 52s that is turnably disposed by main frames 56L, 56R, and sub pressurization rollers 52A, 52B, and 52C that commonly use shaft portion 52s. Meanwhile, upper registration roller 54 includes shaft portion 54s that is turnably supported by main frames 56L, 56R. Upper pressurization roller 55 includes shaft portion 55s that is turnably supported by main frames 56L, 56R.
Engagement holes 56Lh, 56Rh are formed in main frames 56L, 56R. Engagement holes 56Lh, 56Rh respectively engage with protrusion portions 43Lu, 43Ru (
Placement portions 31a, 31b are respectively formed at both ends in the transverse width direction in a tip part of base plate member 31 in base unit 30 illustrated in
In the configuration of
Moreover, protrusion portions 43Ru, 43Lu (
Image formation apparatus 1 described above is provided with a front surface cover that covers the front end of apparatus main body 10 (
As illustrated in
Front surface cover 90 includes protruded press member 91 at the inner side of front surface cover 90. When front surface cover 90 is positioned in the close position, press member 91 pushes the back face (outer surface) of main guide member 47 to bias main guide member 47 to the rear end side of the apparatus. In this case, main guide member 47 rotates in the inner direction and is pushed toward abutted portions 53Lc, 53Rc (
In contrast, when front surface cover 90 is positioned in the open position, as illustrated in
When sub-conveyance unit 40 is moved back to an original state, the user may slide sub-conveyance unit 40 to a position where sub-conveyance unit 40 abuts on medium transport mechanism 50, and push it into the apparatus. Further, the user can fix the position of tip part 47t of main guide member 47 to a position at which tip part 47t directs the inlet-side end (the nip part between lower registration roller 51 and lower pressurization roller 52) in medium transport mechanism 50 by positioning the front surface cover 90 in the close position.
As described above, with image formation apparatus 1 in the first embodiment, medium guide mechanism 46 including main guide member 47 and sub-guide member 48 is attached to one end at the front end side in sub-conveyance unit 40. Sub-conveyance unit 40 is slidably supported by base unit 30. This allows the user to slide sub-conveyance unit 40 together with medium guide mechanism 46 to easily take out sub-conveyance unit 40 to the front end side of the apparatus, as illustrated in
Moreover, image formation apparatus 1 is designed in such a manner that the user (operator) is likely to manually operate at the front end side of apparatus main body 10 (right side in the drawing). Specifically, the user can pull out medium storage cassette 20 in the direction of the front end side of the apparatus to add media Pa or resolve the jam state of medium Pa, and manually feed a medium to MPT 25 that is provided at the front end of the apparatus. In addition, discharge rollers 84A, 84B discharge medium Pa on which a printed image is formed, onto stacker unit 11 in the direction of the front end side. Accordingly, the user can more easily recognize and take out medium Pa on stacker unit 11 at the front end side of the apparatus (at the upstream side in the medium conveyance direction on main conveyance path D0) than at the rear end side of the apparatus (at the downstream side in the medium conveyance direction on main conveyance path D0). In addition, the user can move front surface cover 90 to the open position at the front end side of the apparatus, and then slide and dismount sub-conveyance unit 40 to the outside (
Moreover, medium guide mechanism 46 (main guide member and sub-guide member 48) has a function of merging sub-conveyance path D3 that is a conveyance path for sending back medium Pa to the front end side of the apparatus, with a conveyance path for conveying medium Pa picked up from medium storage cassette 20. Medium guide mechanism 46 is disposed near the front end of apparatus main body 10. As illustrated in
Moreover, in order to guide medium Pa to an accurate position, tip part 47t of main guide member 47 is necessary to be disposed with high position accuracy with respect to the inlet-side end in medium transport mechanism 50 (the nip part between lower registration roller 51 and lower pressurization roller 52). In the embodiment, when front surface cover 90 is in the close position, as illustrated in
In contrast, when front surface cover 90 is moved from the close position to the open position, as illustrated in
Next, a second embodiment according to the invention is described.
Sub-conveyance unit 140 includes, as illustrated in
Main guide member 47 described above in the first embodiment includes, as illustrated in
In the embodiment, protrusion portions 34Ra, 34La are added to the inner surfaces of handle portions 43Rh 43Lh in place of engagement portions 47a, 4 7b. This allows a wider clearance width between main guide member 147 and sub-guide member 48 in the fixed state, compared with that in the first embodiment, because of the expanded range in which main guide member 147 can rotate.
Moreover, the configuration of base unit 130 in the embodiment is the same as the configuration of base unit 30 in the first embodiment except that, as illustrated in
As described above, with the image formation apparatus in the second embodiment, the user can easily take out medium Pa in a jam state between main guide member 147 and sub-guide member 48, because of the wider clearance width between main guide member 147 and sub-guide member 48 when sub-conveyance unit 140 is pulled out from apparatus main body 10. Moreover, press member 91 can push main guide member 147 when front surface cover 90 is moved to the close position because lift members 136L, 136R are provided.
MODIFICATION EXAMPLES OF FIRST AND SECOND EMBODIMENTSIn the foregoing, although the various embodiments according to the invention are described with reference to the drawings, these embodiments are merely examples of the invention, and various forms other than the abovementioned embodiments can be employed. For example, the image formation apparatuses in the first and the second embodiments each include one process unit 60 mounted thereon, and thus have only a function of forming a monochromatic printed image, but the invention is not limited thereto. An image formation apparatus that forms a color printed image can be implemented by preparing multiple process units that are arranged along with main conveyance path D0.
Moreover, the image formation apparatuses in the first and the second embodiments employ a direct transfer method to transfer a developer image onto medium Pa, but the invention is not limited thereto. The structure in which a developer image is transferred onto medium Pa by an intermediate transfer method may be employed.
Note that, in the first embodiment, medium transport mechanism 50 cannot be drawn out to the outside together with sub-conveyance unit 40 because medium transport mechanism 50 is fixed to base unit 30, but the invention is not limited thereto. The structure in the first embodiment may be modified in such a manner that sub-conveyance unit 40 and medium transport mechanism 50 are integrated to allow medium transport mechanism 50 to be drawn out to the outside together with sub-conveyance unit 40.
Further, the printers as image formation apparatuses are exemplified and described in the first and the second embodiments, but the invention is not limited to the printers, and can be applied to copiers, facsimile equipment, or multi function peripherals (MFPs). Note that, the MFP is an image formation apparatus having multiple functions, such as a copier, a printer, an image scanner, and facsimile equipment.
The invention includes other embodiments in addition to the above-described embodiments without departing from the spirit of the invention. The embodiments are to be considered in all respects as illustrative, and not restrictive. The scope of the invention is indicated by the appended claims rather than by the foregoing description. Hence, all configurations including the meaning and range within equivalent arrangements of the claims are intended to be embraced in the invention.
Claims
1. A medium conveyance apparatus for use in an image formation apparatus provided with: a main body including a front end and a rear end being opposed to each other, a medium supply unit disposed in the main body, and a process unit configured to process a medium conveyed along with a main conveyance path in the main body, the medium conveyance apparatus comprising:
- a conveyance mechanism configured to convey the medium along with the main conveyance path from a front end side to a rear end side of the main body;
- a sub-conveyance unit including a sub-conveyance path provided in parallel with the main conveyance path, and configured to send out the medium processed in the process unit by conveying the medium along with the sub-conveyance path from the rear end side to the front end side;
- a medium transport mechanism configured to transport the medium sent out from either one of the sub-conveyance path and the medium supply unit to the main conveyance path; and
- a unit support member supporting the sub-conveyance unit such that the sub-conveyance unit is slidable to the front end side, wherein
- the sub-conveyance unit includes: a plate member defining the sub-conveyance path; and a medium guide mechanism attached to one end of the plate member on the front end side, and
- the medium guide mechanism is configured to guide the medium sent out from the medium supply unit to the medium transport mechanism, and the medium sent out from the sub-conveyance path to the medium transport mechanism.
2. The medium conveyance apparatus according to claim 1, wherein
- the medium guide mechanism includes: a main guide member configured to guide the medium sent out from the medium supply unit to the medium transport mechanism; and a sub-guide member configured to guide the medium sent out from the sub-conveyance path to the medium transport mechanism, wherein
- the sub-guide member is disposed at the rear end side of the main guide member to form a clearance between the sub-guide member and the main guide member, and
- the main guide member is configured to guide the medium sent out from the medium supply unit to pass the medium though the clearance.
3. The medium conveyance apparatus according to claim 2, wherein
- the sub-guide member includes: an inner guide surface configured to guide the medium sent out from the sub-conveyance path to the medium transport mechanism; and an outer guide surface opposed to the main guide member to form the clearance.
4. The medium conveyance apparatus according to claim 2, wherein
- the front end of the main body includes: an opening portion opposed to one end of the sub-conveyance unit; and a front surface cover supported to be movable between a close position where the front surface cover closes the opening portion and an open position where the front surface cover opens the opening portion,
- the main guide member is turnably attached to the one end of the plate member, and
- the front surface cover fixedly biases the main guide member toward the rear end side when being positioned in the close position, and leaves the main guide member turnable without biasing the main guide member when being positioned in the open position.
5. The medium conveyance apparatus according to claim 4, wherein the front surface cover includes a press member configured to bias the main guide member toward the rear end side when being positioned in the close position.
6. The medium conveyance apparatus according to claim 4, wherein the main guide member is rotatable in a direction to enlarge the clearance along with the movement of the front surface cover from the close position to the open position.
7. The medium conveyance apparatus according to claim 1, further comprising a lift member including slanted surfaces on which an end of the main guide member ascends along with a slide operation of the sub-conveyance unit from the front end side to the rear end side.
8. The medium conveyance apparatus according to claim 1, wherein
- the front end of the main body includes: an opening portion opposed to one end of the sub-conveyance unit; and a front surface cover supported to be movable between a close position where the front surface cover closes the opening portion and an open position where the front surface cover opens the opening portion.
9. The medium conveyance apparatus according to claim 1, further comprising a reverse conveyance mechanism configured to reverse front and back sides of the medium on which a printed image is formed, and then supply the medium to the sub-conveyance path.
10. The medium conveyance apparatus according to claim 1, wherein the process unit forms a printed image on the medium in accordance with an electrophotographic method.
11. An image formation apparatus, comprising:
- a main body including a front end and a rear end being opposed to each other;
- a medium supply unit disposed in the main body;
- a process unit configured to process a medium conveyed along with a main conveyance path in the main body;
- a conveyance mechanism configured to convey the medium along with the main conveyance path from a front end side to a rear end side;
- a sub-conveyance unit including a sub-conveyance path provided in parallel with the main conveyance path, and configured to send out the medium processed in the process unit by conveying the medium along with the sub-conveyance path from the rear end side to the front end side;
- a medium transport mechanism configured to transport the medium sent out from either one of the sub-conveyance path and the medium supply unit to the main conveyance path; and
- a unit support member configured to support the sub-conveyance unit is slidable to the front end side, wherein
- the sub-conveyance unit includes: a plate member configured to constitute the sub-conveyance path; and a medium guide mechanism attached to one end of the plate member on the front end side, and
- the medium guide mechanism guides the medium sent out from the medium supply unit to the medium transport mechanism, and the medium sent out from the sub-conveyance path to the medium transport mechanism.
12. The image formation apparatus according to claim 11, wherein
- the medium guide mechanism includes: a main guide member configured to guide the medium sent out from the medium supply unit to the medium transport mechanism; and a sub-guide member configured to guide the medium sent out from the sub-conveyance path to the medium transport mechanism,
- the sub-guide member is disposed at the rear end side of the main guide member to form a clearance between the sub-guide member and the main guide member, and
- the main guide member guides the medium sent out from the medium supply unit to pass the medium though the clearance.
13. The image formation apparatus according to claim 12, wherein
- the front end of the main body includes: an opening portion opposed to one end of the sub-conveyance unit; and a front surface cover supported to be movable between a close position where the front surface cover closes the opening portion and an open position where the front surface cover opens the opening portion,
- the main guide member is turnably attached to the one end of the plate member, and
- the front surface cover fixedly biases the main guide member toward the rear end side when being positioned in the close position, and leaves the main guide member turnable without biasing the main guide member when being positioned in the open position.
14. The image formation apparatus according to claim 11, further comprising a lift member including slanted surfaces on which an end of the main guide member ascends along with a slide operation of the sub-conveyance unit from the front end side to the rear end side.
15. The image formation apparatus according to claim 11, further comprising a reverse conveyance mechanism configured to reverse front and back sides of the medium on which a printed image is formed, and then supply the medium to the sub-conveyance path.
Type: Application
Filed: Jun 3, 2014
Publication Date: Dec 4, 2014
Inventor: Yuta KOBAYASHI (Tokyo)
Application Number: 14/294,246
International Classification: B65H 9/00 (20060101); B65H 7/20 (20060101);