JP2014105106A - Medium supply device and image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the resistance caused when a gas is suctioned.SOLUTION: A medium supply device (21) includes a holding member (22) including: a body part (23) which is supported so as to move along a transfer direction of a medium; a support part (35) which movably supports an enclosing member (36); a first passage (41) formed in the body part (23); a guide part (42) which guides the medium; a second suction port (43) which is formed at the guide part (42); a second passage (45) which is formed at the support part (35) and connects the second suction port (43) with the first passage (41); and a suction device (HF) which is connected with the first passage (41) and suctions a gas, the holding member (22) which suctions and holds the medium (S) at the body part (23).

Description

  The present invention relates to a medium supply device and an image forming apparatus.

  In a conventional electrophotographic image forming apparatus, a technique disclosed in Patent Document 1 below is conventionally known as a medium supply apparatus that sucks and conveys a medium.

  Japanese Patent Laid-Open No. 2002-19978 as Patent Document 1 discloses a configuration in which a sheet is sucked by being exhausted from a small opening (124) formed in a sheet feeding device plenum (58) and conveyed downstream. Is described. In the configuration described in Patent Document 1, when exhaust is performed from the small opening (124), the sheet is adsorbed to the lower end of the sealing mechanism (300) arranged in a suspended state around the plenum (58). Be captured. When the paper is captured and the gap between the lower end of the sealing mechanism (300) and the paper is removed, the interior of the sealing mechanism (300) is further evacuated, and the suspended sealing mechanism ( 300) rises with the paper. Then, when the plenum (58) is moved downstream by the driving device (600), the sheet captured by the feeding roller (55) disposed on the downstream side is delivered and conveyed downstream.

JP 2002-19978 A ("0023" to "0029", FIGS. 2 to 5, 16, and 17)

  This invention makes it a technical subject to reduce the resistance which attracts | sucks gas.

In order to solve the technical problem, the medium supply device according to claim 1 comprises:
A storage container in which a medium is stored;
A loading member that is supported inside the container and on which a medium is loaded;
A main body disposed opposite to the stacking member and supported so as to be movable along the conveyance direction of the medium, a surrounding member extending from the main body toward the stacking member, and a direction approaching and separating from the medium A supporting portion that movably supports the surrounding member along the space, a space surrounded by the surrounding member, a first suction port that is formed in the main body portion and opens to the space, and the main body portion A first flow path that is formed inside and connected to the first suction port, a guide part that guides a medium that is supported by the main body part and conveyed downstream, and the medium side of the guide part A second suction port formed in the support portion, a second flow channel formed in the support and connecting the second suction port and the first flow channel, and connected to the first flow channel And a suction device that sucks the gas, and exhausts the gas by the suction device. A holding member for holding by adsorbing the medium to the main body portion,
A conveying member that is disposed downstream of the holding member in the conveying direction of the medium and conveys the medium adsorbed by the holding member toward the downstream side;
It is provided with.

In order to solve the technical problem, an image forming apparatus according to claim 2 is provided.
The medium supply device according to claim 1,
It is provided with.

  According to invention of Claim 1, 2, compared with the case where a 2nd flow path is not formed in a support part, the resistance which attracts | sucks gas can be reduced.

FIG. 1 is an overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is an enlarged view of a main part of the paper feed tray according to the first embodiment. FIG. 3 is an explanatory diagram of the suction head according to the first embodiment, FIG. 3A is a front view, and FIG. 3B is a plan view. FIG. 4 is a perspective view of the suction head according to the first embodiment when viewed obliquely from below. 5 is a cross-sectional view taken along line VV in FIG. 3B. 6A and 6B are explanatory diagrams of the operation when the sheet of the first embodiment is supplied. FIG. 6A is an explanatory diagram of a state before the image forming operation is started. FIG. It is explanatory drawing of the state which moved to the raise position. FIG. 7 is an operation explanatory diagram when the sheet of Example 1 is supplied, and FIG. 7A is an explanatory diagram of a state in which the medium is adsorbed and air for separating the medium is blown from the state shown in FIG. 6B. 7B is an explanatory diagram of a state in which the suction head has moved from the suction position to the supply position from the state shown in FIG. 7A. FIG. 8 is an explanatory diagram of the operation when the sheet of Example 1 is supplied, FIG. 8A is an explanatory diagram of a state where air blowing is completed from the state shown in FIG. 7B, and FIG. 8B is an adsorption from the state shown in FIG. It is explanatory drawing of the state which the head returned to the adsorption position. FIG. 9 is an explanatory diagram of a conventional suction head.

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 overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention.
In FIG. 1, an image forming apparatus U includes a user interface UI as an example of an operation unit, an image scanner U1 as an example of an image information input device, a paper feeding device U2 as an example of a medium transport device, and an image forming apparatus. It has a main body U3 and a post-processing device U4.

The user interface UI includes an input key such as a copy start key, a copy number setting key, and a numeric keypad as an example of an input unit, and a display unit UI1.
The image scanner U1 includes an automatic document conveying device that automatically conveys a document, a scanner main body as an example of an image reading device, and the like.
The sheet feeding device U2 is an example of a storage container, and includes a plurality of sheet feeding trays TR1 and TR2 as an example of a sheet feeding unit. The sheet feeding trays TR1 and TR2 can accommodate a sheet S as an example of a medium therein. In addition, a paper feed path SH1 as an example of a transport path is formed inside the paper feed device U2. The sheet feed path SH1 extends from each sheet feed tray TR1, TR2 to the main body U3 of the image forming apparatus.

In FIG. 1, the main body U <b> 3 of the image forming apparatus includes a control unit C. The control unit C is configured to be able to input a signal from the image scanner U1. The control unit C outputs a signal for controlling the writing circuit D, the power supply circuit E, and the like.
The writing circuit D outputs a laser drive signal corresponding to image information of Y: yellow, M: magenta, C: cyan, K: black input from the image scanner U1 at a preset time. As an example, the image data is output to the exposure machines ROSy, ROSm, ROSc, and ROSk of each color.

In FIG. 1, photosensitive drums Py, Pm, Pc, and Pk, which are examples of image carriers, are disposed below the exposure units ROSy to ROSk.
Around the photosensitive drum Pk for K color, along the rotation direction of the photosensitive drum Pk, a charger CCk, a developing device GK, a primary transfer roll T1k as an example of a primary transfer device, and an image holding member As an example, a drum cleaner CLk is arranged.
A charging voltage for charging the photosensitive drum Pk is applied from the power supply circuit E to the charger CCk. The developing device GK includes a developing roll R0 as an example of a developer holding body. A developing voltage is applied from the power supply circuit E to the developing roll R0. A primary transfer voltage having a polarity opposite to the charging polarity of the developer is applied from the power supply circuit E to the primary transfer roll T1k.
Note that a toner dispenser U3a as an example of a developer replenishing unit is disposed on the upper portion of the main body U3 of the image forming apparatus.

In the first exemplary embodiment, the photosensitive drum Pk, the charger CCk, and the drum cleaner CLk are unitized as the image carrier unit UK. The image carrier unit UK is detachably supported with respect to the main body U3 of the image forming apparatus.
For each of the colors Y, M, and C, image carrier units UY, UM, and UC configured similarly to the K color are provided. Therefore, each image carrier unit UY, UM, UC also includes photosensitive drums Py, Pm, Pc, chargers CCy, CCm, CCc, and drum cleaners CLy, CLm, CLc.

Further, in Example 1, the K-color photosensitive drum Pk that is frequently used and has a lot of surface wear is configured to have a larger diameter than the other-color photosensitive drums Py, Pm, and Pc, and is capable of high-speed rotation. Long life has been achieved.
In the first exemplary embodiment, the developing devices GY to GK are also unitized and supported so as to be detachable from the main body U3 of the image forming apparatus.
The image carrier units UY, UM, UC, UK and the developing devices GY, GM, GC, GK constitute toner image forming members UY + GY, UM + GM, UC + GC, UK + GK.

A belt module BM as an example of an intermediate transfer device is disposed below the image carrier units UY to UK. The belt module BM includes an intermediate transfer belt B as an example of an intermediate transfer member, belt support rolls Rd, Rt, Rw, Rf, T2a as examples of intermediate transfer member support members, and primary transfer rolls T1y, T1m. , T1c, T1k. The belt support rolls Rd, Rt, Rw, Rf, and T2a include a belt drive roll Rd as an example of a drive member, a tension roll Rt as an example of a tension applying member, a walking roll Rw as an example of a meandering prevention member, and a driven member A plurality of idler rolls Rf as an example and a backup roll T2a as an example of a counter member for secondary transfer are included.
The intermediate transfer belt B is supported by the belt support rolls Rd, Rt, Rw, Rf, T2a so as to be rotatable in the direction of the arrow Ya.

  A secondary transfer unit Ut is disposed below the backup roll T2a. The secondary transfer unit Ut has a secondary transfer roll T2b as an example of a secondary transfer member. The secondary transfer roll T2b is supported by the backup roll T2a so as to be separated from and in contact with the intermediate transfer belt B. An area where the secondary transfer roll T2b is in contact with the intermediate transfer belt B forms a secondary transfer area Q4 as an example of an image recording area. Further, a contact roll T2c as an example of a contact member for applying a voltage is in contact with the backup roll T2a. A secondary transfer voltage having the same polarity as the toner charging polarity is applied to the contact roll T2c from the power supply circuit E at a preset time. The rolls T2a to T2c constitute a secondary transfer device T2.

A belt cleaner CLB as an example of an intermediate transfer member cleaner is disposed on the downstream side of the secondary transfer region Q4 with respect to the rotation direction of the intermediate transfer belt B.
The primary transfer rolls T1y to T1k, the intermediate transfer belt B, the secondary transfer unit T2, the belt cleaner CLB, and the like constitute a transfer device T1 + B + T2 + CLB that transfers the image on the surface of the photosensitive drums Py to Pk to the sheet S.
The photoconductor drums Py to Pk, the developing devices GY to GK, the transfer devices T1 + B + T2 + CLB, and the like constitute a printer unit U3b as an example of the image recording device of the first embodiment.

A medium transport path SH2 is disposed below the belt module BM. The upstream end of the transport path SH2 is connected to the downstream end of the sheet feed path SH1 with respect to the transport direction of the sheet S. A transport roll Ra as an example of a medium transport member is disposed in the transport path SH2.
A registration roll Rr as an example of a delivery timing adjusting member is disposed on the downstream side of the conveyance roll Ra with respect to the conveyance direction of the sheet S.
A registration guide SGr as an example of a medium guide member and a sheet guide SG1 before transfer are sequentially arranged on the downstream side of the registration roll Rr with respect to the conveyance direction of the sheet S.

A post-transfer sheet guide SG2 as an example of a medium guide member is disposed on the downstream side of the secondary transfer region Q4 with respect to the conveyance direction of the sheet S. A conveyance belt BH as an example of a medium conveyance member is disposed on the downstream side of the sheet guide SG2 after transfer with respect to the conveyance direction of the sheet S.
A fixing device F is disposed on the downstream side of the conveyance belt BH with respect to the conveyance direction of the sheet S. The fixing device F includes a heating roll Fh as an example of a heat fixing member and a pressure roll Fp as an example of a pressure fixing member. A fixing region Q5 is formed by a region where the heating roll Fh and the pressure roll Fp are in contact with each other.

A discharge path SH3 as an example of a medium transport path is formed on the downstream side of the fixing device F with respect to the transport direction of the sheet S. The discharge path SH3 extends rightward toward the post-processing device U4.
Further, an inversion path SH4 as an example of a medium transport path is branched downward from the discharge path SH3. In the reversing path SH4, a reversing roll Rb capable of rotating in the forward and reverse directions is disposed as an example of a medium transporting member.
A first gate GT1 as an example of a transfer path switching member is disposed at a position where the reversing path SH4 branches from the discharge path SH3.

The post-processing device U4 has a processing path SH5 as an example of a medium transport path. A decurler U4a as an example of a curvature correction device is disposed in the processing path SH5. The decurler U4a according to the first embodiment includes a first curl correction member h1 and a second curl correction member h2 as examples of a curvature correction member. A switching gate h3 as an example of a conveyance path switching member is disposed on the upstream side of the curl correction members h1 and h2 with respect to the conveyance direction of the sheet S.
A discharge roll Rh as an example of a discharge member is disposed on the downstream side of the decurler U4a with respect to the conveyance direction of the sheet S. A discharge tray TH1 as an example of a discharge unit is disposed on the downstream side of the discharge roll Rh with respect to the conveyance direction of the sheet S. The discharge tray TH1 according to the first exemplary embodiment is supported to be movable in the vertical direction according to the stacking amount of the sheets S.

A second reversing path SH6 as an example of a medium transport path is connected to the upper part of the reversing path SH4. The second inversion path SH6 branches from the inversion path SH4 and extends toward the processing path SH5.
A second gate GT2 as an example of a transfer path switching member is disposed at a branch portion between the reversing path SH4 and the second reversing path SH6. The second gate GT2 is formed of a thin film member that can be elastically deformed. Then, when the sheet S is carried into the reversing path SH4 from the fixing device F, the second gate GT2 is pushed by the sheet S and is elastically deformed so that the sheet S can pass through the position of the second gate GT2. In addition, when the sheet S moves upward along the reversing path SH4, the sheet S is restricted from entering the fixing device F and can be guided to the processing path SH5.

A third inversion path SH7 as an example of a medium transport path is connected to the lower end of the inversion path SH4. The third inversion path SH7 is formed in the lower part of the post-processing device U4. On the reversing path SH4 and the third reversing path SH7, a reversing roll Rb capable of forward and reverse rotation as an example of a medium transporting member is disposed.
A circulation path SH8 as an example of a medium transport path is connected to a connecting portion between the inversion path SH4 and the third inversion path SH7. The circulation path SH8 is formed in the lower part of the main body U2 of the image forming apparatus and inside the sheet feeding device U2. With respect to the conveyance direction of the sheet S, the downstream end of the circulation path SH8 is connected to the upstream end of the conveyance path SH2. A conveyance roll Ra as an example of a medium conveyance member is disposed in the circulation path SH8.

A third gate GT3 as an example of a transfer path switching member is disposed at a connection portion between the reversing path SH4 and the circulation path SH8. Similar to the second gate GT2, the third gate GT3 is formed of a thin-film member that can be elastically deformed. When the sheet S is directed from the reversing path SH4 to the third reversing path SH7, the third gate GT3 is pushed by the sheet S and elastically deformed so that the sheet S can pass through the position of the third gate GT3. In addition, when the sheet S moves from the third reversing path SH7 to the circulation path SH8, the sheet S is restricted from entering the reversing path SH4 and can be guided to the circulation path SH7.
The medium transport path SH of the first embodiment is configured by the elements having the symbols SH1 to SH8. Further, a medium transport system SU is constituted by the elements having the symbols SH, V, Ra, Rr, Rh, SGr, SG1, SG2, BH, GT1 to GT3, and the like.

(Function of image forming apparatus of embodiment 1)
In FIG. 1, when a copy start key is input on the user interface UI, the image scanner U1 reads a document. Image information of the read document is input to the control unit C of the main body U3 of the image forming apparatus. The control unit C outputs a signal corresponding to the input image information to the exposure units ROSy to ROSk through the writing circuit D.
In FIG. 1, the surfaces of the photosensitive drums Py to Pk are charged by the chargers CCy to CCk, respectively. On the photosensitive drums Py to Pk whose surfaces are charged, electrostatic latent images are formed by laser beams Ly, Lm, Lc, and Lk as an example of writing light output from the exposure units ROSy to ROSk. The electrostatic latent images on the surfaces of the photosensitive drums Py to Pk are converted into toner images as examples of visible images of Y: yellow, M: magenta, C: cyan, and K: black by the developing devices GY to GK. Developed.
In the developing devices GY to GK, when the toner is consumed with the development, the toner is supplied from the toner dispenser U3a according to the consumption amount.

The toner images on the surfaces of the photosensitive drums Py to Pk are transferred onto the intermediate transfer belt B by primary transfer rolls T1y to T1k. When a multicolor image, that is, a so-called color image is formed, the toner images on the photosensitive drums Py to Pk are sequentially transferred to the intermediate transfer belt B in a superimposed manner. Further, in the case of only black image data, only K: black photosensitive drum Pk and developing unit GK are used, and only a black toner image is formed. Accordingly, only the black toner image is transferred to the intermediate transfer belt B.
After the primary transfer, the toner remaining on the surface of the photosensitive drums Py to Pk is cleaned by the drum cleaners CLy to CLk.
The toner image transferred to the intermediate transfer belt B is conveyed to the secondary transfer area Q4.

The sheets S accommodated in the paper feed trays TR1 and TR2 are conveyed to the main body U3 of the image forming apparatus through the paper feed path SH1. The sheet S in the conveyance path SH2 is conveyed to the registration roll Rr by the conveyance roll Ra.
The registration roll Rr sends out the sheet S in accordance with the time when the toner image is conveyed to the secondary transfer region Q4. The sheet S sent out by the registration roll Rr is guided by the guides SGr and SG1 and conveyed to the secondary transfer area Q4.
The toner image on the intermediate transfer belt B is transferred to the sheet S by the secondary transfer unit T2 when passing through the secondary transfer region Q4. In the case of a color image, the toner images primarily transferred onto the surface of the intermediate transfer belt B are secondarily transferred to the sheet S at once.
The intermediate transfer belt B after passing through the secondary transfer region Q4 is cleaned of residual toner by a belt cleaner CLB.

The sheet S on which the toner image is secondarily transferred is conveyed to the fixing device F through a medium guide member SG2 after transfer and a conveyance belt BH as an example of a medium conveyance member before fixing. The toner image on the surface of the sheet S is heated and fixed by the fixing device F when passing through the fixing region Q5. The sheet S on which the toner image is heated and fixed in the fixing area Q5 is conveyed through the discharge path SH3.
When the sheet S is discharged to the discharge tray TH1, the first gate GT1 switches the conveyance destination of the sheet S to the processing path SH5. The switching gate h3 switches the conveyance destination to the first curl correction member h1 or the second curl correction member h2 in accordance with the curvature of the sheet S conveyed to the processing path SH5, the so-called curl direction. The curl correction members h1 and h2 correct the curl of the sheet S that passes therethrough. The sheet S with the curl corrected is discharged to the discharge tray TH1 by the discharge roll Rh. In this case, the sheet S is discharged to the discharge tray TH1 with the image surface facing upward, that is, in a so-called face-up state.

  When the sheet S is discharged with the front and back reversed with respect to the discharge tray TH1, the first gate GT1 switches the conveyance destination of the sheet S that has passed through the fixing device F to the reversing path SH4. When the trailing end of the sheet S transported in the reversing path SH4 passes through the second gate GT2, the reversing roll Rb rotates in the reverse direction. Therefore, the sheet S is switched back and forth, that is, so-called switchback. The switched sheet S is guided to the second gate GT2 and conveyed to the processing path SH5 through the second inversion path SH6. Therefore, the sheet S is carried into the processing path SH5 with the front and back sides of the sheet S reversed with respect to the case where the sheet S does not pass through the second inversion path SH6. After the curl is corrected by the decurler U4a, the sheet S whose front and back sides are reversed is discharged onto the discharge tray TH1 in a state where the image surface faces downward, that is, a so-called face-down state.

  When the sheet S is printed on both sides, the first gate GT1 switches the transport destination of the sheet S on which the image is fixed on the first side to the reversing path SH4. The sheet S carried into the reversing path SH4 is transported until the trailing end in the transporting direction passes through the third gate GT3 and enters the third reversing path SH7. The sheet S transported to the third reversing path SH7 is transported by the reversing roll Rb in a state where the transport direction is reversed in the front-rear direction. That is, the sheet S is switched back. The switched back sheet S is guided to the third gate GT3 and carried into the circulation path SH8. The sheet S conveyed through the circulation path SH8 is conveyed to the registration roll Rr through the conveyance path SH2 with the front and back sides reversed.

(Description of paper tray)
FIG. 2 is an enlarged view of a main part of the paper feed tray according to the first embodiment.
Here, regarding each of the paper feed trays TR1 and TR2 of the first embodiment, only the second paper feed tray TR2 disposed below will be described in detail, and the first paper feed tray TR1 will be described in the second Since the configuration is the same as that of the paper feed tray TR2, detailed description thereof is omitted.

In FIG. 2, the second paper feed tray TR2 has a tray main body 1 as an example of a storage unit. Rails 2 as an example of guided members are supported on the left and right ends of the lower portion of the tray body 1. The rail 2 extends in the front-rear direction.
A guide rail 3 as an example of a guide member is disposed on the outer side in the left-right direction with respect to the rail 2. On the guide rail 3, a roller 4 as an example of a rotating member is rotatably supported. The roller 4 is configured to contact the lower surface of the rail 2 so that the rail 2 can be guided in the front-rear direction.

  An elevating plate 11 as an example of a stacking member is supported inside the tray body 1. A stacking surface for the sheets S is formed on the upper surface of the elevating plate 11. The elevating plate 11 is supported so as to be able to move up and down in a state where the sheets S are stacked on the upper surface in accordance with a sheet feeding operation. In addition, the structure which raises / lowers the raising / lowering plate 11 is well-known conventionally, for example, as described in Unexamined-Japanese-Patent No. 2010-143658, Unexamined-Japanese-Patent No. 2010-149982, etc., Various conventionally well-known structures are employable. Therefore, detailed description is omitted.

FIG. 3 is an explanatory diagram of the suction head according to the first embodiment, FIG. 3A is a front view, and FIG. 3B is a plan view.
FIG. 4 is a perspective view of the suction head according to the first embodiment when viewed obliquely from below.
5 is a cross-sectional view taken along line VV in FIG. 3B.
2 to 5, a sheet take-out device 21 as an example of a medium take-out member is disposed above the second paper feed tray TR2. The sheet take-out device 21 has a suction head 22 as an example of a holding member. The suction head 22 has a head main body 23 as an example of a main body portion of a holding member. The head main body 23 according to the first embodiment includes a flat bottom plate portion 24 and side walls 26, 27, 28, and 29 extending in the vertical direction from the front, rear, left, and right of the bottom plate portion 24.

The bottom plate portion 24 has a plurality of intake ports 31 penetrating in the vertical direction as an example of a first suction port.
In addition, an inclined surface 32 as an example of a bending imparting portion is formed on the right portion of the lower surface of the bottom plate portion 24. The inclined surface 32 of the first embodiment is formed in a shape that inclines downward as it goes to the right and inclines to the left as it goes to the center in the front-rear direction. Further, ribs 33 as an example of a bending imparting portion are supported at both front and rear end portions of the bottom surface of the bottom plate portion 24. The rib 33 is formed in a plate shape extending downward from the lower surface of the bottom plate portion 24. Three ribs 33 according to the first embodiment are arranged on each of the front side and the rear side of the bottom plate portion 24, and the three ribs 33 are arranged at intervals in the left-right direction.

In FIG. 3A and FIG. 5, the pin 34 as an example of the support part of an enclosing member is supported on the outer surface of each of the front, rear, and left side walls 26, 27, and 28. Each pin 34 is formed in a cylindrical shape protruding outward from the outer surface of each side wall 26, 27, 28. A plurality of pins 34 are arranged along the outer surfaces of the side walls 26, 27, 28 at intervals in the left-right or front-rear direction.
A support cylinder 35 as an example of a support portion of the surrounding member is supported on the right side wall 29. The support cylinder 35 is formed in a hollow cylindrical shape protruding rightward from the outer surface of the side wall 29. Accordingly, a through hole 35 a is formed inside the support cylinder 35. Two support cylinders 35 according to the first embodiment are arranged at intervals in the front-rear direction.

3A, 4, and 5, a sealing skirt 36 as an example of a surrounding member is disposed on the outer surface of the head body 23. The sealing skirt 36 of the first embodiment is formed in a plate shape extending downward. In the sealing skirt 36, a long hole 36a as an example of a supported portion is formed at a position corresponding to the pin 34 and the support cylinder 35. The long hole 36a is configured by a hole extending in the vertical direction. A pin 34 and a support cylinder 35 pass through the long hole 36a. Therefore, the sealing skirt 36 is supported so as to be movable in the approaching and separating direction with respect to the elevating plate 11 and the sheets S stacked on the elevating plate 11.
Therefore, in the suction head 22 of the first embodiment, the intake port 31 is disposed inside the sealing skirt 36 and the side walls 26 to 29. The space 37 surrounded by the sealing skirt 36, the lower surface of the bottom plate portion 24, and the side walls 26 to 29 constitutes a space 37 to be sucked in the first embodiment.

A lid-shaped cover portion 39 is supported on the upper portion of the head main body 23 as an example of a covering member. The cover part 39 has an upper plate part 39a. The upper plate portion 39a is formed in a plate shape. The upper plate portion 39a closes the space surrounded by the bottom plate portion 24 and the side walls 26 to 29. Side plate portions 39b, 39c, and 39d extend downward from the front, rear, and left ends of the upper plate portion 39a.
3B and 4, an exhaust duct 39f as an example of a connection portion is formed on the right side of the front side plate portion 39b. One end of a bellows 40 as an example of a flexible member is connected to the exhaust duct 39f. An exhaust fan HF as an example of a suction device is connected to the other end of the bellows 40.

A main flow path 41 as an example of a first flow path is configured by a space surrounded by the bottom plate portion 24, the side walls 26 to 29, and the upper plate portion 39a. Therefore, the main flow path 41 of the first embodiment constitutes a flow path through which the gas sucked from the air intake space 37 through the intake port 31 passes when the exhaust fan HF is operated.
In FIG. 5, a connection path 41 a as an example of a flow path is formed at the right end of the main flow path 41. The connection path 41 a extends rightward from the main flow path 41 toward the support cylinder 35. In the first embodiment, the support cylinder 35 is disposed at a position corresponding to the vertical height of the main channel 41. Therefore, the support cylinder 35 of the first embodiment is disposed above the other pins 34.

3 to 5, a sheet guide 42 as an example of a guide portion is disposed on the right side of the head main body 23. In FIG. 3B, the length in the front-rear direction of the sheet guide 42 according to the first embodiment is set to a length that can pass between the transport rolls Ra that are arranged with a space in the front-rear direction. In the conveyance roll Ra according to the first exemplary embodiment, the interval between the inner ends of the conveyance roll Ra is set to be smaller than a preset width of the minimum usable sheet S.
The sheet guide 42 has a supported portion 42a. The supported portion 42 a of the first embodiment is formed in a plate shape facing the front side wall 29. The supported portion 42 a is fixedly supported at the right end of the support cylinder 35. A guide main body 42b as an example of a main body of the guide portion is formed at the lower end of the supported portion 42a. The guide body 42b is formed in a plate shape extending rightward. In addition, although illustration is abbreviate | omitted, the lower surface of the guide main body 42b is curving with respect to the front-back direction, and the function as a curve provision part is provided.

A guide intake port 43 as an example of a second suction port is formed on the lower surface of the guide main body 42b. Two intake ports 43 of the guide according to the first embodiment are arranged at intervals in the front-rear direction so as to correspond to the position of the support cylinder 35.
Inside the sheet guide 42, a guide channel 44 as an example of a gas channel is formed. The guide channel 44 extends from the guide inlet 43 to the support cylinder 35.
The through hole 35a, the connection path 41a, and the guide flow path 44 constitute the second flow path 45 of the first embodiment.
The suction head 22 according to the first embodiment is configured by the members denoted by reference numerals 23 to 45.

  A shaft guide portion 46 as an example of a guided portion for movement is supported on the upper surface of the cover portion 39. A through hole 46a is formed inside the guide portion 46 of the shaft. The through hole 46a penetrates in the left-right direction, which is the medium transport direction. An outer peripheral surface of a linear ball bearing 47 as an example of a bearing member is supported in the through hole 46a. On the inner peripheral surface of the linear ball bearing 47, a guide shaft 48 as an example of a guide member is supported in a penetrating state. The guide shaft 48 is formed in a rod shape extending along the left-right direction, which is the medium conveyance direction. The guide shaft 48 is supported by the frame 49 of the paper feeding device U2. The guide portion 46 of the shaft according to the first embodiment is supported by the guide shaft 48 through a linear ball bearing 47 so as to be movable in the left-right direction and not rotatable.

On the upper surface of the guide portion 46 of the shaft, a wire fixing portion 51 as an example of a connecting portion is supported. A wire 52 as an example of a wire is fixedly supported on the wire fixing portion 51.
A pulley 53 as an example of a support member is disposed on the left and right sides of the wire fixing portion 51. Further, a drive pulley 54 as an example of a drive member is disposed in front of the right pulley 53. A driven pulley 56 as an example of a driven member is disposed in front of the left pulley 53. The wire 52 is stretched around the pulleys 53 to 56. Rotation is transmitted to the drive pulley 54 from a motor M1 capable of forward and reverse rotation as an example of a drive source.

In FIG. 2, an air blowing device 57 as an example of a medium separation device is disposed between the suction head 22 and the transport roll Ra. The air blowing device 57 blows air for medium separation to the suction head 22 from obliquely downward to the right. Note that the structure for separating the medium by blowing air is described in, for example, Japanese Patent Application Laid-Open No. 11-89625, Japanese Patent Application Laid-Open No. 2008-94603, Japanese Patent Application Laid-Open No. 2005-194027, and the like. Therefore, detailed description is omitted.
The wire 52, the pulleys 53 to 56, the motor M1, and the like constitute the head driving devices 52 to 56 + M1 of the first embodiment as an example of the holding member driving device. Further, the suction head 22, the bellows 40, the exhaust fan HF, the head driving devices 52 to 56 + M1, the air blowing device 57, and the like constitute the sheet take-out device 21 of the first embodiment.

In FIG. 3, the control unit C of the image forming apparatus U according to the first exemplary embodiment includes a sheet feeding control unit C1 that controls the sheet feeding apparatus U2. The paper feed control unit C1 includes a head drive unit C11 as an example of a conveyance control unit, a fan control unit C12 as an example of a suction control unit, and a blowing control unit C13 as an example of a whirling control unit.
The head driving means C11 has a supply control means C11A, and controls the driving and position of the suction head 22 by controlling the forward and reverse rotation of the motor M1.
The supply control unit C11A rotates the motor M1 forward or backward based on the supply timing of the sheet S during the sheet S supply operation. The supply controller C11A moves the suction head 22 to a suction position above the sheet S when the sheet is sucked. Further, the supply control unit C11A moves the suction head 22 to a supply position on the right side of the suction position when the sucked sheet S is conveyed downstream.

The fan control means C12 controls the exhaust fan HF to cause the suction head 22 to suck the sheet S. The fan control unit C12 according to the first exemplary embodiment operates the exhaust fan HF when the sheet feeding operation is started and the sheet S is attracted. Therefore, the fan control means C12 starts the suction of the sheet S. When it is determined that the suction head 22 has moved to the supply position, the fan control unit C12 stops the exhaust of the exhaust fan HF.
The spray control means C13 controls the air spray device 57 to spray air onto the sheet S sucked by the suction head 22. That is, when a plurality of sheets S are adsorbed, the blowing control means C13 blows air between the sheets S, separates them, and spreads them. The spray control means C13 of the first embodiment starts the air spray by operating the air spray device 57 after a preset spray start time t3 has elapsed since the fan control means C12 started the suction. . And the spray control means C13 will complete | finish the spray of air, if the preset spray time t4 passes after the spray start. In the first embodiment, the spraying start time t3 is set in advance by experimentally measuring the time from when the exhaust fan HF is activated until the sealing skirt 36 is raised to the upper end. Further, the spraying time t4 is set by measuring in advance an experiment or the like so that the sheet S can be sufficiently separated by spraying air.

(Operation of Example 1)
6A and 6B are explanatory diagrams of the operation when the sheet of the first embodiment is supplied. FIG. 6A is an explanatory diagram of a state before the image forming operation is started. FIG. It is explanatory drawing of the state which moved to the raise position.
In the image forming apparatus U according to the first embodiment having the above-described configuration, before the job as the image forming operation is started, as shown in FIG. 6A, the lift plates 11 of the paper feed trays TR1 and TR2 move to the lowered position. doing. Further, the suction head 22 has moved to the suction position.
When the job is started, the elevating plate 11 is raised to the raised position shown in FIG. 6B, and the uppermost sheet S of the bundle of sheets S stacked on the stacking plate 11 is close to the lower end of the sealing skirt 36. It becomes.

FIG. 7 is an operation explanatory diagram when the sheet of Example 1 is supplied, and FIG. 7A is an explanatory diagram of a state in which the medium is adsorbed and air for separating the medium is blown from the state shown in FIG. 6B. 7B is an explanatory diagram of a state in which the suction head has moved from the suction position to the supply position from the state shown in FIG. 7A.
Next, the exhaust fan HF is actuated to exhaust the space 37 sucked from the exhaust port 26a through the bellows 40 and the exhaust duct 39f. When the intake space 37 is sucked, the uppermost sheet S is adsorbed to the lower end of the sealing skirt 36. At this time, when the sheet S comes into contact with the lower surface of the sealing skirt 36, the sucked space 37 is almost sealed. That is, the inflow of gas from the outside is restricted to the space 37 to be sucked.
If the exhausted space 37 is further exhausted from this state, the sealed inspired space 37 is in a low pressure state. Accordingly, the sheet S rises together with the sealing skirt 36, and the state shown in FIG. 7A is obtained.

At this time, one or a plurality of sheets S may be attracted to the lower surface of the uppermost sheet S by static electricity or the like and may rise together. Here, the sheet S that has risen together with the sealing skirt 36 is bent when the exhaust is further performed while the sealing skirt 36 has moved to the upper end. Therefore, the bent sheet S comes into contact with the inclined surface 32 and the rib 33 and is in a wavy state. Further, the right end portion, which is the downstream end portion in the conveyance direction of the sheet S, also comes into contact with the lower surface of the guide main body 42b and is curved. The curved state of the sheet S is different between the uppermost sheet S and the lower sheet S, and a gap is generated between the sheets S. Therefore, the lower sheet S is easily separated from the uppermost sheet S that receives the suction force.
In the image forming apparatus U according to the first embodiment, when the exhaust of the space 37 to be sucked is started, the air blowing device 57 is also operated. Therefore, air is blown from the air blowing device 57 to the sheet S. Therefore, air is blown against the gap between the sheets S generated due to the difference in the curved state. Therefore, the other sheets S are separated from the uppermost sheet S. The separated sheet S falls and is stacked on the lift plate 11.
Therefore, even if a plurality of sheets S are first sucked by the suction head 22, the single sheet S is finally sucked by the suction head 22.

In the suction head 22 according to the first exemplary embodiment, even when separation air is blown onto the sheet S, the upper surface of the front end portion in the transport direction of the sheet S is supported by the guide body 42b. Therefore, the front end portion in the conveyance direction of the sheet S is reduced from being curled upward. In particular, in the suction head 22 according to the first embodiment, when the exhaust fan HF is operated, intake is performed from the intake port 43 of the seat guide 42. Therefore, the front end portion in the conveyance direction of the sheet S is adsorbed to the lower surface of the guide main body 42b. Accordingly, the front end of the sheet S in the conveyance direction is stably held by the sheet guide 42.
When the sheet S is sucked to the suction head 22, the motor M1 rotates and the wire 52 rotates in the clockwise direction in FIG. 3B. Therefore, the suction head 22 supported by the wire 52 via the wire fixing portion 51 moves to the supply position in the right direction along the guide shaft 48. When the front end of the sheet S sucked by the suction head 22 in the transport direction reaches the transport roller Ra, the sheet S is sandwiched by the transport roller Ra and transported downstream as shown in FIG. 7B.

FIG. 8 is an explanatory diagram of the operation when the sheet of Example 1 is supplied, FIG. 8A is an explanatory diagram of a state where air blowing is completed from the state shown in FIG. 7B, and FIG. 8B is an adsorption from the state shown in FIG. It is explanatory drawing of the state which the head returned to the adsorption position.
In FIG. 8A, when the sheet S is delivered to the transport roller Ra, the air blowing is finished. Then, the motor M1 rotates in the reverse direction, and the suction head 22 is returned to the suction position as shown in FIG. 8B. At this time, when the sheet S passes through the sealing skirt 36, the sealed space 37 is released. Therefore, as shown in FIG. 8B, the sealing skirt 36 descends downward.

Here, when the sheet guide 42 is not provided, the front end of the sheet S receives an air flow as the suction head 22 moves, and the front end of the sheet S may be rolled up or drooped downward. . Further, the air may be blown up or drooped by being blown from the air blowing device 57. In particular, when one side of the sheet S is used, or when curling or so-called curl is generated on the sheet S due to the influence of temperature or humidity, there is a high possibility that the curling or dripping will occur. If the front end of the sheet S rolls up or hangs down, it may be caught when it is transferred to the transport roller Ra. When the sheet S is caught, a paper jam occurs and a paper feed failure occurs.
On the other hand, in the suction head 22 of the first embodiment, the exhaust fan HF is operating while the suction head 22 moves from the suction position to the supply position. Accordingly, the front end portion in the conveyance direction of the sheet S is continuously held while being attracted to the sheet guide 42. Therefore, the front end of the sheet S is reliably delivered to the transport roller Ra.

FIG. 9 is an explanatory diagram of a conventional suction head.
In FIG. 9, in the conventional suction head 01, the pins 03 that support the sealing skirt 02 all have a common configuration in front, rear, left, and right. That is, the through-hole 35a was not formed in the pin 03.
Therefore, the sheet guide 04 is formed in a shape that largely encircles the sealing skirt 02 in accordance with the movable range of the sealing skirt 02. Therefore, when the suction port 04 a is to be formed in the sheet guide 04, the air flow path 06 has to be largely circulated along the sheet guide 04 and connected to the main flow path 07.

Therefore, in the conventional configuration, the air flow path 06 has a long flow path length and a shape with many corners. Therefore, when air is sucked by the exhaust fan, the length of the flow path and the large number of corners become the suction resistance. Therefore, the suction force of the suction port 04a is reduced, and the suction of the sheet S may be insufficient.
Correspondingly, when the exhaust amount of the exhaust fan is increased, there are problems that the fan and the motor are enlarged and the suction head 01 is enlarged, the manufacturing cost and power consumption are increased, and the noise is increased. It was. Further, when a dedicated exhaust fan is provided for the suction port 04a of the seat guide 04, there is a problem that the number of parts increases and the cost increases.

On the other hand, in the suction head 22 of the first embodiment, the support cylinder 35 supports the sealing skirt 36, and a through hole 35a constituting a flow path is formed inside. That is, the support cylinder 35 serves as both a member that supports the sealing skirt 36 and a member that constitutes the flow path. Therefore, it is not necessary to rotate the air flow path 06 as in the conventional configuration, and the length of the flow path is shortened and the bending angle is reduced as compared with the conventional configuration. Therefore, the suction resistance is reduced, and it becomes easy to sufficiently secure the suction force that the suction port 43 sucks the sheet S. Therefore, it is possible to suppress an increase in the size of the suction head 22, an increase in cost and power consumption, an increase in noise, and the like.
In the first embodiment, the support cylinder 35 supports not only the sealing skirt 36 but also the sheet guide 42. Therefore, the support cylinder 35 of the first embodiment also serves as a member that supports the sheet guide 42. Therefore, the seat guide 42 is reduced in size as it does not need to go upward as compared with the conventional configuration.

(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 performed within the range of the summary of this invention described in the claim. It is possible. Modification examples (H01) to (H06) of the present invention are exemplified below.
(H01) In the above-described embodiment, the present invention is not limited to a copying machine as an example of an image forming apparatus, and can be applied to an image forming apparatus such as a printer or a FAX. Further, the present invention is not limited to a color image forming apparatus, and can be applied to a monochrome image forming apparatus. Further, the present invention is not limited to a tandem type image forming apparatus, and can be applied to a rotary type image forming apparatus. Further, the present invention is not limited to the electrophotographic image forming apparatus, and can be applied to other types of image forming apparatuses such as an ink jet recording system and a thermal transfer system.

(H02) In the above-described embodiment, the configuration in which the sealing skirt 36 surrounding the outer periphery is disposed on the suction head 22 is exemplified, but the number and size of the sealing skirts are not limited thereto. For example, a skirt for accommodating a small-sized sheet such as a postcard can be additionally arranged inside the sealing skirt 36. That is, it is possible to arrange a plurality of skirts according to the size of the sheet.
(H03) In the above-described embodiment, the configuration in which the air inlet 43 is formed in the seat guide 42 is exemplified, but the present invention is not limited to this. In addition to the downstream side in the transport direction of the sheet S, a guide and an intake port may be added to the suction head 22 on the upstream side in the transport direction of the sheet S and on both sides in the width direction.

(H04) In the above-described embodiment, the size of the seat guide 42 and the positions, sizes, number, and the like of the intake port 43 and the support tube 35 can be arbitrarily changed according to the design, specifications, and the like.
(H05) In the embodiment, the configuration of the sealing skirt 36 as an example of the enclosing member is not limited to the plate-like form exemplified in the embodiment. For example, in order to allow the sealing skirt to follow the bending of the sheet S that occurs when the sheet S is separated, a plurality of strip-like members hang down and form a “goodwill” shape, or elastically deformed when the bending occurs It is possible to change the form and configuration such as a body or a curtain shape.

(H06) In the above embodiment, the second flow path 45 is not limited to the exemplified configuration, and the configuration of the head body 23, the position of the support cylinder 35, the shape of the sheet guide 42, the length, the position of bending, and the number of times of bending. It can be changed according to the size and the like.

11: Loading member,
21 ... Medium supply device,
22 ... holding member,
23 ... body part,
31 ... first suction port,
34, 35 ... support part,
36 ... enclosing member,
37 ... space,
41 ... 1st flow path,
42 ... Guide part,
43 ... second suction port,
45 ... second flow path,
HF ... suction device,
Ra: conveying member,
S ... medium,
TR1, TR2 ... container,
U: Image forming apparatus.

Claims (2)

A storage container in which a medium is stored;
A loading member that is supported inside the container and on which a medium is loaded;
A main body disposed opposite to the stacking member and supported so as to be movable along the conveyance direction of the medium, a surrounding member extending from the main body toward the stacking member, and a direction approaching and separating from the medium A supporting portion that movably supports the surrounding member along the space, a space surrounded by the surrounding member, a first suction port that is formed in the main body portion and opens to the space, and the main body portion A first flow path that is formed inside and connected to the first suction port, a guide part that guides a medium that is supported by the main body part and conveyed downstream, and the medium side of the guide part A second suction port formed in the support portion, a second flow channel formed in the support and connecting the second suction port and the first flow channel, and connected to the first flow channel And a suction device that sucks the gas, and exhausts the gas by the suction device. A holding member for holding by adsorbing the medium to the main body portion,
A conveying member that is disposed downstream of the holding member in the conveying direction of the medium and conveys the medium adsorbed by the holding member toward the downstream side;
A medium supply apparatus comprising: The medium supply device according to claim 1,
An image forming apparatus comprising:

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