JP2006076754A - Paper discharge tray device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To bring a state where rear ends of sheets discharged onto the sheet support surface of a stack tray are rested against a rear end support member, into a state where the sheets are bundled and stacked on the horizontal sheet support surface overlappingly in a vertical direction. <P>SOLUTION: This paper discharge tray device 1 comprises the stack tray 2 rotatably between a tilted attitude tilted upward as the sheet support surface extends forward in the sheet discharge direction and a horizontal attitude, a lowering device M1+13 to 15 lowering the stack tray 2 according to a sheet loaded amount, a stack tray rotating device M2+11+16 to 19 rotating the sheet support surface from the tilted attitude to the horizontal attitude in the moved state of the stack tray 2 to the lower end position, and a rear end support member moving device M3+21+24+25 moving forward the rear end of the sheets on the stack tray 2 by moving forward the lower end part of the sheet rear end support member in the sheet discharge direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a paper discharge tray apparatus having a stack tray from which images recorded by an image forming apparatus such as a printer or a copying machine are discharged, and in particular, a stack having a sheet support surface whose front in the sheet discharge direction is inclined obliquely upward. The present invention relates to a paper discharge tray device including a tray.
The paper discharge tray apparatus of the present invention is suitably used for a paper discharge tray apparatus having a stack tray (elevator type stack tray) that can move up and down to discharge a large amount of sheets. For example, the present invention is applied to a sheet discharge tray device having an elevator stack tray capable of discharging a large amount of sheets, which is provided in a finisher or the like in a medium speed cut sheet printer.

  Usually, the shape of the stack tray is inclined so that the downstream side in the sheet discharge direction becomes higher so that the end faces in the sheet discharge direction are aligned. Further, the stack tray sequentially moves downward according to the amount of sheets discharged onto the sheet support surface, and the position of the upper surface position of the sheet bundle on the stack tray (the surface supporting the sheet discharged to the stack tray) is It is configured to always have the same height.

Patent Documents 1 to 4 and the like are conventionally known as the type of stack tray.
(Patent Document 1: Japanese Patent Laid-Open No. 9-20455)
(Patent Document 2: JP-A-9-20457)
Patent Documents 1 and 2 describe a stack tray that moves downward in the vertical direction.
(Patent Document 3: Japanese Patent Laid-Open No. 7-300200)
(Patent Document 4: JP-A-8-108965)
Patent Documents 3 and 4 describe a stack tray that is inclined slightly downward from a vertically downward direction to a downstream side in the sheet discharge direction.

Japanese Patent Laid-Open No. 9-20455 Japanese Patent Laid-Open No. 9-20457 Japanese Patent Laid-Open No. 7-300200 JP-A-8-108965

(Problems of the techniques described in Patent Documents 1 to 4)
In the stack tray, the rear end of each sheet bundle discharged and stacked on the inclined sheet support surface of the stack tray is leaned against the rear end support member. When the inclination angle of the sheet support surface and the inclination angle of the rear end support member are damaged, it becomes almost impossible to take out at once when the number of stacks is 1,500 sheets or 2,000 sheets of plain paper. There is a problem in that the stack sheets must be taken out in a divided manner and the stacked sheets at the time of taking out remain inclined.
In view of the above circumstances, the present invention has the following description (O01) as a technical problem.
(O01) The sheet bundle discharged and stacked on the stack tray can be easily taken out.

  Next, the present invention devised to solve the above problems will be described. In order to facilitate correspondence with the constituent elements of the embodiments described later, the constituent elements of the present invention are not described. Add the code enclosed in parentheses. The reason why the present invention is described in correspondence with the reference numerals of the embodiments described later is to facilitate the understanding of the present invention, and not to limit the scope of the present invention to the embodiments.

(First invention)
In order to solve the above-mentioned problem, the tray device of the first invention is characterized by comprising the following structural requirements (A01) to (A03).
(A01) A stack tray (2) on which the image-recorded sheets (S) are discharged and the discharged sheets (S) are sequentially stacked, and the sheet support surface is inclined upward as going forward in the sheet discharging direction. The stack tray (2) rotatable between the inclined posture and the horizontal posture,
(A02) A lowering device (M1 + 13-15) for lowering the stack tray (2) according to the sheet stacking amount,
(A03) A stack tray rotating device (M2 + 11 + 16 to 19) that rotates the sheet supporting surface from the inclined posture to the horizontal posture with the stack tray (2) moved to the lower end position.

(Operation of the first invention)
In the sheet discharge tray device according to the first aspect of the present invention having the above-described configuration requirements (A01) to (A03), the sheet support surface can be rotated between an inclined posture inclined upward and a horizontal posture as it goes forward in the sheet discharge direction. On the correct stack tray (2), the sheets (S) on which the images are recorded are discharged, and the discharged sheets (S) are sequentially stacked.
The lowering device (M1 + 13 to 15) lowers the stack tray (2) according to the sheet stacking amount.
The stack tray rotating device (M2 + 11 + 16 to 19) rotates the sheet support surface from the inclined posture to the horizontal posture with the stack tray (2) moved to the lower end position. When the sheet support surface rotates to the horizontal posture, the sheet can be easily taken out.

(First Embodiment 1)
The paper discharge tray device according to the first aspect of the present invention is characterized in that in the first aspect of the present invention, the following structural requirement (A04) is provided.
(A04) The stack tray rotating device (M2 + 11 + 16-19) that automatically rotates the sheet supporting surface from the inclined posture to the horizontal posture when the stack tray (2) is moved to the lower end position.
(Operation of Form 1 of the First Invention)
In the paper discharge tray device according to the first aspect of the first invention having the configuration requirement (A04), the stack tray rotating device (M2 + 11 + 16 to 19) is configured so that the stack tray (2) moves to the lower end position. The seat support surface is automatically rotated from the inclined posture to the horizontal posture.

(First Embodiment 2)
A paper discharge tray device according to a second aspect of the first invention is characterized in that the following structural requirements (A05) and (A06) are provided in the first invention or the first aspect of the first invention.
(A05) A sheet rear end support member (21) for positioning and supporting the rear end of the sheet discharged to the stack tray (2), wherein the upper end is rotatably supported and the lower end is movable in the sheet discharge direction. Sheet rear end support member (21),
(A06) With the stack tray (2) moved to the lower end position, the lower end portion of the sheet rear end support member (21) is moved forward in the sheet discharge direction to move the sheet rear end on the stack tray (2). Rear end support member moving device for moving forward (M3 + 21 + 24 + 25).

(Operation of the second aspect of the first invention)
In the sheet discharge tray device according to the second aspect of the present invention having the above-described structural requirements (A05) and (A06), the sheet rear end support member whose upper end is rotatably supported and whose lower end is movable in the sheet discharge direction (21) positions and supports the trailing edge of the sheet discharged to the stack tray (2). The rear end support member moving device (M3 + 21 + 24 + 25) moves the lower end portion of the sheet rear end support member (21) forward in the sheet discharge direction with the stack tray (2) moved to the lower end position. 2) Move the rear end of the upper sheet forward.
At this time, the sheet bundle supported on the upper surface of the stack tray (2) has an angle near the perpendicular to the upper surface of the stack tray (2).

(Embodiment 3 of the first invention)
A paper discharge tray device according to a third aspect of the first invention is characterized in that the following constitutional requirement (A07) is provided in the first invention or the first or second aspect of the first invention.
(A07) When the stack tray (2) is moved to the lower end position, the lower end portion of the sheet rear end support member (21) is automatically moved forward in the sheet discharge direction to move the sheet rear on the stack tray (2). The rear end support member moving device (M3 + 21 + 24 + 25) for moving the end forward.
(Operation of the third aspect of the first invention)
In the paper discharge tray device according to the third aspect of the first invention having the structural requirement (A07), the rear end support member moving device (M3 + 21 + 24 + 25) is arranged so that the rear of the sheet is moved when the stack tray (2) is moved to the lower end position. The lower end portion of the end support member (21) is automatically moved forward in the sheet discharging direction, and the sheet rear end on the stack tray (2) is moved forward.

(Second invention)
The paper discharge tray device according to the second aspect of the invention is characterized by comprising the following structural requirements (A01), (A02), (A05), and (A06).
(A01) A stack tray (2) on which the image-recorded sheets (S) are discharged and the discharged sheets (S) are sequentially stacked, and the sheet support surface is inclined upward as going forward in the sheet discharging direction. The stack tray (2) rotatable between the inclined posture and the horizontal posture,
(A02) A lowering device (M1 + 13-15) for lowering the stack tray (2) according to the sheet stacking amount,
(A05) A sheet rear end support member (21) for positioning and supporting the rear end of the sheet discharged to the stack tray (2), wherein the upper end is rotatably supported and the lower end is movable in the sheet discharge direction. Sheet rear end support member (21),
(A06) With the stack tray (2) moved to the lower end position, the lower end portion of the sheet rear end support member (21) is moved forward in the sheet discharge direction to move the sheet rear end on the stack tray (2). Rear end support member moving device for moving forward (M3 + 21 + 24 + 25).

(Operation of the second invention)
In the sheet discharge tray device according to the second aspect of the present invention having the structural requirements (A01), (A02), (A05), and (A06), the sheet support surface is inclined upward and horizontally as it goes forward in the sheet discharge direction. On the stack tray (2) which can be rotated between the postures, the sheet (S) on which the image is recorded is discharged, and the discharged sheets (S) are sequentially stacked. The lowering device (M1 + 13 to 15) lowers the stack tray (2) according to the sheet stacking amount.
The sheet rear end support member (21) whose upper end is rotatably supported and whose lower end is movable in the sheet discharge direction positions and supports the sheet rear end discharged to the stack tray (2).
When the printing operation is finished and a large amount of stacked sheets are taken out from the stack tray (2), they are leaned against the tray descending slope and aligned.
The rear end support member moving device (M3 + 21 + 24 + 25) moves the lower end portion of the sheet rear end support member (21) forward in the sheet discharge direction with the stack tray (2) moved to the lower end position. 2) Move the rear end of the upper sheet forward. At this time, the sheet bundle supported on the upper surface of the stack tray (2) has an angle near the perpendicular to the upper surface of the stack tray (2).
Thereafter, when the stack tray (2) is rotated so that the upper surface thereof is horizontal, the stack of stack sheets stands vertically, so that it is easy to take out the sheet bundle from the stack tray (2).

(Third invention)
The tray device according to the third aspect of the invention is characterized by comprising the following structural requirements (A01) and (A03 ').
(A01) A stack tray on which sheets on which images have been recorded are discharged and on which the discharged sheets are sequentially stacked, and between the inclined posture and the horizontal posture in which the sheet support surface is inclined upward as it goes forward in the sheet discharging direction. The stack tray can be rotated by
(A03 ′) A stack tray rotating device that rotates the sheet support surface of the stack tray from the inclined posture to the horizontal posture.

(Operation of the third invention)
In the tray device according to the third aspect of the present invention having the structural requirements (A01) and (A03 '), the sheet support surface is rotatable between an inclined posture inclined upward and a horizontal posture as it goes forward in the sheet discharging direction. On the stack tray (2), the sheets (S) on which the images are recorded are discharged, and the discharged sheets (S) are sequentially stacked.
The stack tray rotating device (M2 + 11 + 16 to 19) rotates the sheet support surface of the stack tray (2) from the inclined posture to the horizontal posture. When the sheet support surface rotates to the horizontal posture, the sheet can be easily taken out.

The aforementioned paper discharge tray device of the present invention has the following effect (E01).
(E01) It is possible to easily take out the sheet bundle that is discharged and stacked in a large amount on the stack tray.

Next, specific examples (examples) of the embodiment of the paper discharge tray device of the present invention 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.

Example 1
FIG. 1 is an overall explanatory view of an image forming apparatus (tandem digital color copying machine) provided with a first embodiment of a paper discharge tray apparatus of the present invention.
In FIG. 1, the image forming apparatus U includes a UI (user interface), an image input apparatus U1, a paper feeding apparatus U2, an image forming apparatus main body U3, and a paper processing apparatus U4.

(User interface UI):
The UI has a copy start key (not shown), a copy number setting key, an input key such as a numeric keypad, and a display UI1.
(Image input device U1):
The image input device U1 includes an automatic document feeder and an image scanner.
In FIG. 1, in the image input device U1, reflected light from an illuminated original (not shown) is reflected by an exposure optical system (not shown) and a CCD (solid-state imaging device) belt-shaped pile fabric image processing circuit (not shown). (Red), G (green), and B (blue) image data are converted and input to the image forming apparatus body U3 at a predetermined timing.

(Paper Feeder U2):
The sheet feeding device U2 includes a plurality of sheet feeding trays TR1 to TR4, a sheet feeding path SH1 for taking out the recording sheets S for image recording accommodated in the sheet feeding trays TR1 to TR4, and conveying them to the image forming apparatus body U3. Have.

(Image forming apparatus body U3):
In FIG. 1, an image forming apparatus body U3 includes an image recording unit (details will be described later) for recording an image on a recording sheet S conveyed from the sheet feeding device U2, a toner dispenser device U3a, a sheet conveying path SH2, and a sheet discharge. A path SH3, a sheet reversing path SH4, a sheet circulation path SH6, and the like are included.
Further, the image forming apparatus main body U3 includes a control C, a laser driving circuit D and a power supply circuit E controlled by the control C, and the like. The laser drive circuit D, the operation of which is controlled by the control C, is laser driven in accordance with Y (yellow), M (magenta), C (cyan), and K (black) image data input from the image input device U1. Signals are output to the toner image forming apparatuses UY, UM, UC, and UK of latent images forming apparatuses ROSy, ROSm, ROSc, and ROSk of the respective colors at a predetermined timing. The toner image forming apparatuses UY, UM, UC, UK of the respective colors are movable between a drawing position pulled out in front of the image forming apparatus main body U3 and a mounting position mounted inside the image forming apparatus main body U3. It is supported by.

In FIG. 1, a charging device CCk, a developing device Gk, a cleaner CLk, and the like are disposed around a photosensitive drum (toner image carrier) Pk of a K (black) toner image forming apparatus UK.
Further, around the photosensitive drums Py, Pm, and Pc of other toner image forming apparatuses UY, UM, and UC, chargers CCy, CCm, CCc, and developing units Gy, similar to those around the photosensitive drum Pk, respectively. Gm, Gc, cleaners CLy, CLm, CLc, etc. are arranged.

  In FIG. 1, photosensitive drums Py, Pm, Pc, Pk are uniformly charged by chargers CCy, CCm, CCc, CCk, respectively, and then output from the latent image forming devices ROSy, ROSm, ROSc, ROSk. An electrostatic latent image is formed on the surface by the laser beams Ly, Lm, Lc, and Lk. The electrostatic latent images on the surfaces of the photosensitive drums Py, Pm, Pc, and Pk are Y (yellow), M (magenta), C (cyan), and K (black) colors by developing units Gy, Gm, Gc, and Gk. The toner image is developed.

The toner images on the surfaces of the photosensitive drums Py, Pm, Pc, and Pk are sequentially transferred onto the intermediate transfer belt B by the primary transfer rolls T1y, T1m, T1c, and T1k, and a color image is transferred onto the intermediate transfer belt B. It is formed. The color toner image formed on the intermediate transfer belt B is transferred to the secondary transfer area Q.
4 is conveyed.

In the case of only black image data, only the K (black) photosensitive drum Pk and the developing device Gk are used, and only a black toner image is formed.
After the primary transfer, residual toner on the surface of the photosensitive drums Py, Pm, Pc, and Pk is cleaned by the photosensitive drum cleaners CLy, CLm, CLc, and CLk.

  The belt module BM includes a belt support roll (Rd, Rt, Rw, Rd, Rt, Rw, belt drive roll Rd, tension roll Rt, walking roll Rw, a plurality of idler rolls (free rolls) Rf, and a backup roll T2a. Rf, T2a) and the primary transfer rolls T1y, T1m, T1c, T1k. 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 roll T2b of the secondary transfer unit Ut is disposed so as to be separated and press-contactable (separable) to the backup roll T2a with the intermediate transfer belt B interposed therebetween, and the secondary transfer roll T2b is arranged as an intermediate transfer belt. A secondary transfer region Q4 is formed by a region (nip) in pressure contact with B. A contact roll T2c is in contact with the backup roll T2a, and a secondary transfer device (transfer device) T2 is constituted by the rolls T2a to T2c.
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 controlled by the control C at a predetermined timing.

A sheet conveyance path SH2 is disposed below the belt module BM. The recording sheet S fed from the sheet feeding path SH1 of the sheet feeding device U2 is conveyed to the registration roll Rr of the sheet conveying path SH2, and the timing at which the color toner image is conveyed to the secondary transfer region Q4. In addition, the sheet is conveyed to the secondary transfer region Q4 through the registration-side sheet guide SGr and the pre-transfer sheet guide SG2.
The registration-side sheet guide SGr is fixed to the image forming apparatus main body U3 together with the registration roll Rr.
The color toner image on the intermediate transfer belt B is transferred onto the recording paper S by the secondary transfer device T2 when passing through the secondary transfer region Q4. In the case of a full-color image, the toner images primarily transferred onto the surface of the intermediate transfer belt B are secondarily transferred onto the recording paper S all at once.

  The intermediate transfer belt B after the secondary transfer is cleaned by a belt cleaner CLB. Note that the secondary transfer roll T2b and the belt cleaner CLB are disposed so as to be separable (separate and contactable) from the intermediate transfer belt B.

The recording sheet S on which the toner image is secondarily transferred is an area where the pair of fixing rolls Fh and the pressure rolls Fp of the fixing device F are in pressure contact with each other through the post-transfer sheet guide SG3 and the sheet conveying belt BH (fixing area). Transported to Q5. The toner image on the recording paper S is heated and fixed by the fixing device F when passing through the fixing region Q5. A switching gate GT1 is provided on the downstream side of the fixing device F. The switching gate GT1 selectively switches the recording sheet S, which has been conveyed through the sheet conveyance path SH2 and heated and fixed in the fixing region Q5, to either the sheet discharge path SH3 or the sheet reversing path SH4. The sheet S conveyed to the sheet discharge path SH3 is conveyed to the sheet conveyance path SH5 of the sheet processing apparatus U4.
After curling is corrected by the curling correction member U4a disposed in the paper transport path SH5, the paper rolls up from the discharge roll Rh to the stack tray 2 of the discharge tray device 1 of the paper processing device U4 (the image fixing surface of the paper faces upward). It is discharged at.

  The sheet conveyed to the sheet reversing path SH4 side of the image forming apparatus main body U3 by the switching gate GT1 is conveyed to the sheet reversing path SH4 of the image forming apparatus main body U3 through the mylar gate GT2 constituted by a sheet member. . After reversing the sheet conveyed to the sheet reversing path SH4, the sheet is conveyed to the sheet conveying paths SH3 and SH5 and faced down to the stack tray (sheet discharge tray) 2 of the sheet processing apparatus U4 (sheet image fixing surface). Can be discharged downward). In that case, the sheet is switched back immediately after the rear end of the sheet passes through the Mylar gate GT2. The Mylar gate GT2 once passes the recording sheet S conveyed to the sheet reversing path SH4, and once the recording sheet S passed through is switched back and conveyed, it is conveyed to the sheet processing device U4 side.

A sheet circulation path SH6 is connected in the middle of the sheet reversing path SH4 of the image forming apparatus main body, and a mylar gate GT3 is disposed at the connection portion. The downstream end of the sheet reversing path SH4 of the image forming apparatus main body is connected to the sheet reversing path SH7 of the sheet processing apparatus U4.
The sheet transported to the sheet transport path SH4 through the switching gate GT1 is transported to the sheet reversing path SH7 side of the sheet processing apparatus U4 by the mylar gate GT3. The Mylar gate GT3 once passes the recording sheet S conveyed through the sheet reversing path SH4 as it is, and when the recorded recording sheet S is switched back, the switched-back sheet is conveyed to the sheet circulation path SH6 side.
The recording sheet S conveyed to the sheet circulation path SH6 is retransmitted to the transfer area Q4 through the sheet feeding path SH1.

  The sheet conveyed from the sheet conveyance path SH3 or SH4 to the sheet processing apparatus U4 is conveyed from the sheet conveyance path SH5 of the sheet processing apparatus U4 to the gate GT4. The curl correction device U4a is disposed on the downstream side of the gate GT4 in the sheet conveyance direction. The curl correction device U4a includes a first curl correction member L1 and a second curl correction member L2. The gate GT4 conveys the sheet conveyed from the sheet conveying path SH5 to either the first curl correction member L1 or the second curl correction member L2 according to the curl direction of the sheet. The first and second curl correction members L1 and L2 have a curl correction rotating belt and a curl correction rotating roll pressed against the curl correction rotating belt. The paper passing through the nip, which is the pressure contact area between the curl correction rotating belt and the curl correction rotating roll pressed against it, is corrected for curl.

A sheet transport path SH is constituted by the elements indicated by the symbols SH1 to SH7. Further, the sheet conveying device SU is constituted by the elements indicated by the symbols SH, Ra, Rr, Rh, SGr, SG1 to SG3, BH, and GT1 to GT3.
The sheet discharged from the discharge roll Rh is discharged to the stack tray 2.

(Stack tray)
FIG. 2 is a front view of the stack tray, and shows a state where the stack tray is moved to the upper end position by a solid line and a state where the stack tray is moved to the lower end position by a two-dot chain line.
3A and 3B are explanatory views of the stack tray. FIG. 3A is a top view of the stack tray as seen from the arrow IIIA in FIG. 2, and FIG. 3B is a view as seen from the arrow IIIB-IIIB in FIG.
FIG. 4 is a front view of the stack tray, and shows a state where the stack tray has moved to the lower end position by a solid line and a state where the stack tray has moved to the upper end position by a two-dot chain line.
5A and 5B are explanatory views of the stack tray. FIG. 5A is a top view of the stack tray as viewed from the arrow VA in FIG. 4, and FIG. 5B is a view as viewed from the arrow VB-VB in FIG.

2 to 5, the paper discharge tray device 1 has a stack tray 2. The upper surface of the stack tray 2 is formed as a sheet support surface that supports the sheet S. A lever contact surface 2a is formed at the left end portion of the stack tray 2 over the entire length in the front-rear direction, and a sheet rear end support member through hole 2b is formed at the center portion in the front-rear direction.
A through shaft 3 penetrating the stack tray 2 forward and backward passes through sliders 5 and 5 disposed at both front and rear ends of the stack tray 2. The shaft head 3 a at the front end of the through shaft 3 is in contact with the front surface of the front slider 5, and the nut 4 that is screwed into the screw at the rear end of the through shaft is in contact with the rear surface of the slider 5. Accordingly, the stack tray 2 is supported so as to be rotatable around the through shaft 3 supported by the sliders 5 and 5.
A pair of guide shafts 6 and 6 penetrating up and down the front and rear sliders 5 are arranged to be inclined rightward as they go downward. The upper ends of the guide shafts 6, 6 are fixed by an upper end fixing member 7, and the lower ends are fixed by a lower end fixing member 8. The guide shafts 6 and 6 guide the sliders 5 to be slidable in the vertical direction.

  Lever receiving grooves 5a, 5a extending in the front-rear direction are formed in the vertical middle portion of the left end portions of the pair of sliders 5, 5, and the L-shaped lever 11, 11 is supported so as to be rotatable about vertical axes 12 and 12. A torsion spring (not shown) is provided on the outer periphery of the vertical shafts 12 and 12, and the L-shaped levers 11 and 11 are always held at the positions shown in FIG. 3A by the elastic force of the not-shown torsion spring. The L-shaped lever 11 has a contact portion 11 a that contacts the lever contact surface 2 a and an operation portion 11 b that rotates the L-shaped lever 11.

  An endless timing belt 13 extending in the vertical direction is connected to the central portion of the rear end of the stack tray 2 in the front-rear direction. The timing belt 13 is rotatably supported by a driving pulley 14 and a driven pulley 15. The stack pulley 2 connected to the timing belt 13 can be moved up and down by causing the tray lifting motor M1 to rotate the drive pulley 14 forward or backward. The lowering device (M1 + 13 to 15) for lowering the stack tray 2 according to the sheet stacking amount is configured by the elements (M1 + 13 to 14) indicated by the symbols M1, 13 to 15.

In FIG. 9 showing the state in which the stack tray 2 is lowered to the solid line position in FIG. 4, the upper ends of the operation levers 16 and 16 are arranged facing the operation portions 11b and 11b of the pair of L-shaped levers 11. . The operation levers 16 and 16 are rotatable around horizontal shafts 16 a and 16 a extending in the left and right directions, and lower ends thereof are connected to outer ends of the wires 17 and 17. The inner ends of the wires 17 and 17 are connected to a wire take-up roll 18. The operation levers 16 and 16 are pulled by tension springs 19 and 19 connected to the lower ends of the operation levers 16 and 16 and are always held in the state shown in FIG.
When the wire winding roll 18 is rotated by the tray rotating motor M2 to wind the wires 17 and 17, the upper end portions of the operating levers 16 and 16 are rotated outward and the operating portions of the L-shaped levers 11 and 11 are rotated. 11b and 11b are rotated outward. At that time, the contact portions 11a and 11a of the L-shaped levers 11 and 11 are configured to be detached from the lever contact surface 2a. By the elements (M2 + 11 + 16-19) indicated by the symbols M2, 11, 16-19, the sheet support surface is automatically rotated from the inclined posture to the horizontal posture when the stack tray 2 is moved to the lower end position. A stack tray rotating device (M2 + 11 + 16 to 19) is configured.

FIG. 6 is an explanatory view of the sheet rear end support member, and shows a state in which the sheet rear end support member is held at the normal position.
FIG. 7 is an explanatory diagram of the sheet rear end support member, and shows the state where the sheet rear end support member has moved to the sheet pushing position.
3, 5, and 6, the sheet rear end support member 21 that vertically penetrates the sheet rear end support member through hole 2 b is provided at a pair of shafts 22, 22 and a right end of the pair of shafts 22, 22. And a connected plate 23. The shafts 22 and 22 are arranged to be separated in the front-rear direction and extend in the vertical direction, and their upper end portions are supported so as to be rotatable around a horizontal axis 21 a extending in the front-rear direction.

An arcuate gear 24 is connected to the lower end portion of the seat rear end support member 21, and the arcuate gear 24 meshes with a gear 25 rotated by a motor (not shown). When the gear 25 is rotated by the sheet bundle pushing motor M3 and the rear end support member 21 is rotated about the horizontal axis 21a from the state shown in FIG. 6 to the state shown in FIG. 7, it is supported on the stack tray 2. The sheet bundle S thus moved moves to the right on the stack tray. At this time, the rear end edge of the sheet bundle S is held in a substantially perpendicular posture with respect to the upper surface of the stack tray 2. With the elements indicated by the symbols M3, 21, 24, and 25, the lower end portion of the sheet trailing end support member 21 is moved forward in the sheet discharge direction in a state where the stack tray 2 is moved to the lower end position. 2, a rear end support member moving device (M3 + 21 + 24 + 25) for moving the rear end of the sheet forward is configured.
The stack tray 1 of the first embodiment is configured by the elements indicated by the reference numerals 2 to 25.

(Operation of Example 1)
FIG. 8 is a view seen from the arrow VIII in FIG. 7, and is a top view of the stack tray.
FIG. 9 is a view showing a state in which the L-shaped lever is rotated in the state of FIG.
FIG. 10 is a front view of the stack tray. A two-dot chain line shows a state where the stack tray is in the position shown in FIG. 8, that is, the same state as FIG. 7, and a solid line shows the stack tray in the position shown in FIG. It is a figure which shows a state.
In the tray apparatus according to the first embodiment having the above-described configuration, the drive pulley 14 and the timing belt 13 are rotated in accordance with the sheet discharge amount to lower the stack tray 2, and the height of the sheet discharge surface (on the stack tray 2). The sheet upper surface height) is always kept constant.
Since the job (printing) in the image forming apparatus U is finished and the stack tray 2 of the paper processing apparatus U4 recognizes a state in which a large amount of discharged paper is accumulated, the control unit lowers the stack tray 2 during printing. Count the number of times. If the number of downs reaches the specified number n, it is considered that the stack capacity is large (over 1,000 sheets of plain paper), and the stack tray 2 is once lowered to the lowest point position.
(See FIG. 6).

With the stack tray 2 moved to the lower end position, the gear 25 is rotated to move the arcuate gear 24 and the lower end of the sheet rear end support member 21 to the right. Then, the left end (the rear end in the sheet transport direction) of the sheet bundle S on the stack tray 2 moves to the right (the front in the sheet transport direction) and changes from the state shown in FIG. 6 to the state shown in FIG. At this time, the front and rear ends of the sheet bundle S in the sheet conveyance direction are substantially perpendicular to the upper surface of the stack tray 2 (see FIG. 7).
In this way, the correction operation for removing the inclination of the stack sheet bundle S is performed.

In this state, when the wire take-up roll 18 is rotated by a tray rotating motor (not shown) and the wires 17 are wound, the upper ends of the operation levers 16 and 16 are turned outward to rotate the L-shaped lever. 11 and 11 are rotated from the position of FIG. 8 to the position of FIG. At that time, the contact portions 11a and 11a of the L-shaped levers 11 and 11 are detached from the lever contact surface 2a. At this time, the stack tray 2 is rotated from the two-dot chain line position in FIG. 10 to the solid line position by the action of gravity.
In the state in which the stack tray 2 is rotated to the solid line position in FIG. 10, the upper surface (sheet support surface) of the stack tray 2 is substantially horizontal, and the front end and the rear end of the sheet bundle S stacked on the upper surface of the stack tray 2. The end is substantially perpendicular to the upper surface of the stack tray 2 and is held in a stable posture. In this state, the sheet bundle S can be easily taken out at a time.

(Example of change)
Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Can be done. A modified example (H01) of the present invention is exemplified below.
(H01) The present invention can be applied not only to a sheet discharge tray apparatus of a sheet processing apparatus but also to a sheet discharge tray apparatus of various image forming apparatuses such as a printer, a copying machine, a FAX, and a multifunction peripheral. Further, the present invention can be applied not only to an electrophotographic image forming apparatus but also to a paper discharge tray of an ink jet recording type image forming apparatus.

FIG. 1 is an overall explanatory view of an image forming apparatus (tandem digital color copying machine) provided with a first embodiment of a paper discharge tray apparatus of the present invention. FIG. 2 is a front view of the stack tray, and shows a state where the stack tray is moved to the upper end position by a solid line and a state where the stack tray is moved to the lower end position by a two-dot chain line. 3A and 3B are explanatory views of the stack tray. FIG. 3A is a top view of the stack tray as seen from the arrow III in FIG. 2, and FIG. 3B is a view as seen from the arrow IIIB-IIIB in FIG. FIG. 4 is a front view of the stack tray, in which the state where the stack tray is moved to the lower end position is indicated by a solid line, and the state where the stack tray is moved to the upper end position is indicated by a two-dot chain line. FIG. 5 is an explanatory view of the stack tray. FIG. 5A is a top view of the stack tray as seen from the arrow V in FIG. 4, and FIG. 5B is a view as seen from the arrow VB-VB in FIG. FIG. 6 is an explanatory view of the sheet rear end support member, and shows a state in which the sheet rear end support member is held at the normal position. FIG. 7 is an explanatory diagram of the sheet rear end support member, and shows the state where the sheet rear end support member has moved to the sheet pushing position. FIG. 8 is a view seen from the arrow VIII in FIG. 7, and is a top view of the stack tray. FIG. 9 is a view showing a state in which the L-shaped lever is rotated in the state of FIG. FIG. 10 is a front view of the stack tray. A two-dot chain line shows a state where the stack tray is in the position shown in FIG. 8, that is, the same state as FIG. 7, and a solid line shows the stack tray in the position shown in FIG. It is a figure which shows a state.

Explanation of symbols

M1 + 13-15 ... descending device,
M2 + 11 + 16 to 19 ... Stack tray rotating device,
M3 + 21 + 24 + 25 ... rear end support member moving device S ... sheet,
2 ... Stack tray,
21 ... Seat rear end support member,

Claims (6)

A tray device having the following structural requirements (A01) to (A03);
(A01) A stack tray on which sheets on which images have been recorded are discharged and on which the discharged sheets are sequentially stacked, and between the inclined posture and the horizontal posture in which the sheet support surface is inclined upward as it goes forward in the sheet discharging direction. The stack tray can be rotated by
(A02) A lowering device for lowering the stack tray according to the sheet stacking amount;
(A03) A stack tray rotating device that rotates the sheet supporting surface from the inclined posture to the horizontal posture in a state where the stack tray is moved to the lower end position. The tray device according to claim 1, comprising the following constituent elements (A04):
(A04) The stack tray rotating device that automatically rotates the sheet supporting surface from the inclined posture to the horizontal posture when the stack tray moves to a lower end position. The tray device according to claim 1 or 2, comprising the following constituent elements (A05) and (A06):
(A05) A sheet rear end support member for positioning and supporting the rear end of the sheet discharged to the stack tray, wherein the upper end is rotatably supported and the lower end is movable in the sheet discharge direction,
(A06) Rear end support member movement in which the lower end portion of the sheet rear end support member is moved forward in the sheet discharging direction and the sheet rear end on the stack tray is moved forward while the stack tray is moved to the lower end position. apparatus. The tray device according to any one of claims 1 to 3, comprising the following constituent elements (A07):
(A07) When the stack tray moves to the lower end position, the lower end of the sheet rear end support member is automatically moved forward in the sheet discharge direction to move the sheet rear end on the stack tray forward. Support member moving device. A tray device having the following components (A01), (A02), (A05), (A06),
(A01) A stack tray on which sheets on which images have been recorded are discharged and on which the discharged sheets are sequentially stacked, and between the inclined posture and the horizontal posture in which the sheet support surface is inclined upward as it goes forward in the sheet discharging direction. The stack tray can be rotated by
(A02) A lowering device for lowering the stack tray according to the sheet stacking amount;
(A05) A sheet rear end support member for positioning and supporting the rear end of the sheet discharged to the stack tray, wherein the upper end is rotatably supported and the lower end is movable in the sheet discharge direction,
(A06) Rear end support member movement in which the lower end portion of the sheet rear end support member is moved forward in the sheet discharging direction and the sheet rear end on the stack tray is moved forward while the stack tray is moved to the lower end position. apparatus. A tray device having the following components (A01) and (A03 ′),
(A01) A stack tray on which sheets on which images have been recorded are discharged and on which the discharged sheets are sequentially stacked, and between the inclined posture and the horizontal posture in which the sheet support surface is inclined upward as it goes forward in the sheet discharging direction. The stack tray can be rotated by
(A03 ′) A stack tray rotating device that rotates the sheet support surface of the stack tray from the inclined posture to the horizontal posture.

Images