JPS59177229A - Paper feeder - Google Patents

Abstract

PURPOSE:To permit a paper feeding board to be positioned through raising and lowering said board without generating slip by engaging an endless chain onto a part of the paper feeding board of an elevator system paper feeder and allowing sprockets engaged with the endless chain to be revolved normally and reversely by a motor. CONSTITUTION:On the paper feeding side of a copying machine, a paper feeding means in unit of an elevator system paper feeding apparatus 11 on the lower stage and a paper-supporting plate pushin-up type paper feeding apparatus 12 on the upper stage is arranged, and said elevator system paper feeding apparatus 11 is equipped with a paper feeding board 13 in which both edges of a base 25 are fixed onto a movable block 24 which can be raised and lowered along a pair of guide rails 23 at right and left. Each movable block 24 is connected to the endless chains 29 and 30 laid between the upper and the lower sprockets 26 and 27 through a bracket 31. The lower sprockets 27 at right and left are installed onto the both edges of a common rotary shaft 32, which is revolved by the operation of a reversible electric motor 34 through a gear box 35, gear trains 36, 37, and 33. Thus, generation of slip on the paper feeding board is prevented by using sprockets.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an elevator-type paper feeding device for feeding paper provided in, for example, a copying machine.

[Technical background of the invention and its problems]

This type of paper feeding device is widely used because it is extremely convenient for making a large number of copies in succession. This paper feeding device is equipped with a paper feeding tray that lifts and lowers the sheets on which paper is placed, and takes out the sheets of paper on this feeding tray one by one by rotation of a paper feeding roller and supplies them to the image forming section of the copying device. It has become. Furthermore, when the number of sheets on the paper feed tray decreases, the paper feed tray is raised by the operation of a drive mechanism, and the topmost sheet of paper is positioned within a certain paper feeding range so that it can be continuously fed. .

However, in the past, a part of the flat belt on the paper feed tray was connected, and the flat belt was moved forward and backward by the rotation of the drive roller to raise and lower the paper feed tray. There is a problem in that the sheet feeding table cannot be positioned at a predetermined position due to slipping between the sheets, resulting in a decrease in sheet feeding performance.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and its object is to provide a paper feeding device in which the paper feeding tray can be moved up and down and positioned at a predetermined position without causing slippage. .

[Summary of the invention]

In order to achieve the above object, the present invention engages a part of the paper feed tray with an endless chain, meshes a sprocket with this endless chain, and rotates the sprocket forward and backward with a motor to raise and lower the paper feed tray. It is something that makes you

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows the main body of a copying apparatus. A document table 2 is arranged on the right side of the upper surface of the main body 1, and a copying mechanism (not shown) housed in the main body 1 is operated and controlled in the front part. An operation panel 6 is arranged, which includes a print button 3, a numeric keypad 4, a display iJ5, etc. for displaying the status. In addition, a paper ejection tray 8 is provided at the upper left side of the main body 1 to receive the copied paper P' ejected from the paper ejection lower.
A box-shaped cover 9 made of a semi-transparent member is attached to the lower part of the box so as to project from the inside.

As shown in FIG. 2, the cover 9 is pivoted at the rear edge side so that it can be opened and closed. Parts of the paper feeder 11 and the support plate push-up type feeder #12 can be exposed as necessary.

Then, the copy paper PL... is set on the paper feed tray 13 of the elevator type paper feed device 11, and the paper feed cassette 15 is inserted and removed onto the cassette holder 14 of the push-up type paper feeder #12. You can do it freely. Further, on the paper feed table 13, there are 100 copies of copy paper P1 of a size (for example, A4 size) that requires a large number of continuous copies.
In addition, in the paper feed cassette 15, there are 2 copies of copy paper P, etc. of other sizes (for example, B5 size) that need to be changed frequently when copying small numbers of sheets.
It can accommodate approximately 00 sheets.

Further, a protrusion 16 is protruded from the lower edge of the cover 9, and a small hole 17 is formed on the main body 1 side opposite to the protrusion 16, the size of which does not allow insertion of fingers. An actuator 18a of a switch 18 for detecting cover opening/closing is opposed to this small hole 17, and the switch 18 is turned on and off in accordance with the opening/closing operation of the cover 9.

The elevator type paper feeder #11 and the support plate push-up type paper feeder i12 are made into a boiling unit with the former on the lower stage and the latter on the upper stage. That is, as shown in FIG. 3, the cassette holder 14 is installed above the upper surface of the support base 19 fixed in the main body 1 between the left and right frames 20 and 21 on which it is placed. A paper feed table 13 is arranged.

Brackets 2 are installed on the front end surfaces of the left and right frames 20 and 21.
Guide rails 23.23 are attached to the guide rails 23.23 with both upper and lower end portions fixed through 2.22, and movable blocks 24.24 are held by these guide rails 23.23 so as to be movable up and down. Both ends of the base 25 of the paper feed table 13 are fixed to these movable blocks 24,24.

Furthermore, the movable blocks 24.24 are connected to the left and right frames 2.
Upper sprocket 26 and lower sprocket 27 are located on the outer wall side of 0.21 mm and along the guide rails 23, 23.
, are connected via brackets 31.31 to first and second endless chains 29.30, which are respectively tensioned via tension sprockets 28. These 18th
and second endless chains 29 and 30 are stretched across the paper feed table 13 and facing each other. moreover,
Lower left and right sprockets? 7. ．． ! 7 is the common rotation axis 3
A driven gear 33 is fitted to both ends of the rotary shaft 32, and a driven gear 33 is fitted to the left end of the rotating shaft 32, so that they rotate together. The driven gear 33 is interlocked via an intermediate gear 37 with a drive gear 36 to which the driving force of a reversible electric motor 34 is transmitted via a gear box 35.

By rotating the reversible electric motor 34 in the forward or reverse direction, the endless chain 29, 30 is rotated in the forward direction (in the direction of the solid line arrow) or in the reverse direction (in the direction of the dashed line arrow).
It constitutes a chain drive mechanism 38 that causes the chain to run.

Additionally, the chain drive mechanism 38 is the lower limit detection mechanism 3.
9 and the upper limit detection mechanism 4o, the paper feed tray 13 is connected to
It constitutes a paper feed tray operating mechanism 41 that moves the paper feed tray.

At the rear lower part of the cassette holder 14, a lower paper ejecting mechanism 42 as an ejecting means is arranged, and at the rear upper part there is an upper paper ejecting mechanism 43. A restart paper feed roller 44 is arranged in the paper direction. On the left frame 20 side, a paper feed roller drive mechanism 45 for operating the upper and lower paper ejecting mechanisms 43 and 43 and the restart paper feed roller 44 is disposed, and the upper or lower copy paper p2. After selectively taking out the paper p, the paper is fed to an image transfer section (not shown) or the like at a certain timing. That is, sprockets 4g and 49.50 correspond to the left end side of the drive shaft 46.47 of the paper takeout mechanism 42.43 and the left end side of the restart paper feed roller 44.
is arranged and an endless chain 51 is strung around it,
This endless chain 51 travels endlessly via a drive sprocket 52 disposed within the main body 1, thereby rotating at the same time. In addition, the sprocket 4
8 is connected to the drive shaft 46 via the first electromagnetic clutch 53, and the sprocket 49 is connected to the second electromagnetic clutch 54.
The sprocket 50 is configured to interlock with the drive shaft 47 via the drive shaft 47, and with the restart paper feed roller 44 via mutually meshing gears 55 and 56 and a third electromagnetic clutch 57. And the above 1.
The second electromagnetic clutch 53, 54 selectively operates according to the paper feed signal to drive either one of the drive shafts 46, 47 of the paper take-out mechanism 42, 43, and the third overlapping clutch 57 operates at the paper feed timing. It is designed to work accordingly.

Further, a presser roller 58 rolls into contact with the upper part of the paper feed roller 44 for restarting due to its own weight, and the copy paper '+' is moved between these rollers.
, (Pt) and sends it out.

Further, above the paper ejecting mechanism 42 for the lower stage, a push-up lever 6 is provided as a push-up means for a resistance plate push-up/release mechanism 59.
0 is arranged and the paper ejecting mechanism 42.4
Paper presence/absence detection mechanisms 61 and 62 are disposed near 3.

Note that 63 is a cover installed below the paper feed table 13 to cover the gear box 35 of the chain drive mechanism 38, the reversible electric motor 34, etc., and the cover opening/closing detection switch 18 is located on the right side of the front end surface. It is attached. Also,
This cover 63 is located at the lower limit position of the paper feed table I3.
They are mounted at a position that forms a sufficient gap H so that there is no danger even if fingers are inserted between these mutually opposing surfaces.

64 is a mounting plate 6 attached to the bottom side of the reversible motor 34.
5 is a capacitor placed on top of the capacitor. Also, 66.6'
l is placed on the right side of the upper surface of the cassette holder I4, and is a movable member (not shown) provided on the lower surface side of the paper feed cassette 15 that is displaced in accordance with the movement position of the movable guide plate (not shown) of the paper feed cassette 15. ) is a paper size detection switch that turns ON and OFF.

Further, as shown in FIG. 4, a fixed guide plate 68 is provided on the left side of the movement path of the paper feed table 13, and a movable guide plate 69 is provided on the right side.
are arranged to guide both end surfaces of the copy sheets P1, . The movable guide plate 69 is connected to the paper feed roller unit 70 on the right side of the lower paper take-out mechanism 42 via a connecting member 71, and the copy paper P on which the movable guide plate 69 is set
When the paper feed roller unit 70 on the right side is moved in accordance with the size of paper feed roller unit 1, the paper feed roller unit 70 on the right side is configured to move together. The distance from the left side of the copy paper P1 to the center of the left paper feed roller unit 72 is equal to the distance from the right end of the copy paper P1 to the center of the right paper feed roller unit 70.

Further, the paper feed roller units 70, 72 are constructed as shown in detail in FIG. 5. That is, 73 is an arm with a U-shaped cross section, and a rising wall 73a of this arm 73
, 73b has a bushing holding hole 75 which is a long hole that can guide the bushings 74 and 74 in a vertically movable manner from the end side in the paper feeding direction.
75, a positioning hole 77.77 consisting of a hollow hole capable of passing through the stopper shaft 76, and a bushing holding hole 79.77 consisting of a hollow hole capable of firmly holding the bushing 78.711.
79 are formed one after another. Also, the rising wall 73a of the arm 73.

7sb, the drive sprocket 80 is located at a position corresponding to the bushing holding hole 79, 79, and the bushing holding hole 75.
A driven sprocket 81 is arranged at a position corresponding to 75. A driving sprocket 80 is attached to a midway portion of the drive shaft 46 via a one-sided clutch 82, and a driven sprocket 81 is attached to a paper feed roller shaft 83, and is connected to the arm 73 and the shaft 46.
．． The positional relationship with 83 is the above-mentioned bushes 7g, 7B, 74.
It is maintained by 74. Further, an endless chain 84 is wrapped around the driving sprocket 80 and the driven sprocket 81, so that the driving force of the drive shaft 46 can be transmitted to the paper feed roller shaft 83.

Paper feed rollers 85 are provided at both ends of the paper feed roller shaft 83.
．． 85 are fitted and fixed to the shaft 83 via setscrews 86, respectively.

Note that 87... is a retainer for holding the bushes 7B, 7B, 74.74 in place. It's a ring.

Therefore, the paper feed roller unit 7 configured in this way
0.72, the arms 73 are swingable around the drive shaft 46 up to the point where the end faces of the positioning holes 77 and 77 come into contact with the stopper shaft 76, and the paper feed roller shaft 83 is also long. A bushing 7 is provided on the upper and lower end surfaces of the bushing holding hole 75 and 75.
4.74 is in a state where it can move up and down in the range until it comes into contact with it. Further, as shown in FIG. 6C, the end faces of the collars of the bushes 74, 74 and the rising wall 73a of the arm 73.

It has a structure in which minute gaps G and G are formed between the paper feed roller shaft 83 and the outer wall surface of the paper feed roller shaft 83, as shown in FIG. 6(b). It is configured to be swingable so that it can tilt upward to the right, downward to the left, downward to the right, and upward to the left within the range of angle α.

Further, on the left end side of the stopper shaft 76, a paper feed roller 85.
A transmission member 90 is attached to transmit the vertical vibration of the switch 85 to the switch operating lever 89. This transmission member 90
is made by bending a wire, and has an arc-shaped portion 90 formed in the middle.
a, 90a is externally fitted onto the stopper shaft 76, so that it can be rotated about the axis of the stopper shaft 76. Further, while one end 90b of the transmission member 90 is in contact with the circumferential surface of a bushing 74 that pivotally supports the paper feed roller shaft 83, the other end 90C is rotatably attached to the left end of the stopper shaft 76. It engages with the elongated hole g9a at the lower end of the switch operating lever 89. The upper end of the switch operating lever 89 faces the actuator 91F1 of the upper limit detection switch 9I attached to the left frame 20. As shown in FIG. 7(a), the uppermost copy sheet P1 is separated from the paper feed roller 85, 85, and the bushes 74, 74 that pivotally support the paper feed roller shaft 83 are located in the bush holding hole 75. 75, the actuator 91a of the upper limit detection switch 9 is pushed by the switch operating lever 89 and is in the ON state. moreover,
As shown in FIG.
4.74 is on the upper end side of the bush holding hole 75.75, this amount of displacement is transmitted to the switch actuation lever 89 via the transmission member 90, and the switch actuation lever moves away from the actuator 91a of the upper limit switch 91. The upper limit switch 91 is turned OFF by rotating the upper limit switch 91, and constitutes the upper limit detection mechanism 40.

Further, as shown in detail in FIG. 8, the paper feed tray I3 includes a base 25, a spacer guide 92, a presser plate 93, and a copy sheet P1.
A plurality of trays 94°95 of different sizes and a plurality of mounting screws 96 are selectively used depending on the size of the
, 97.97. Base 25 above
At the left end of the tray support piece 98, which is a cut and raised piece cut and raised in an inverted shape so as to protrude upward, is provided as a tray support part.
, 98 are formed, and a rectangular opening window 99 for escape of the movable side plate is formed along the longitudinal direction in the center portion in the width direction on the right end side.

Screw member passing slits 100, 100 are formed along the front and rear edges of the opening of the movable side plate escape window 99. Support portions 98a, 98 of the tray support pieces 98°98
At the center of a is a mounting screw 96.9 inserted through a threaded part insertion hole 101.101 drilled on the left side of the trays 94, 95.
Screw holes 102, 102 into which screw portions 6 are screwed are provided.

The spacer guide 92 is placed along the lateral direction on the right side of the upper surface of the base 25, and has a guide protrusion 1 protruding from the lower surface.
0,? , J03 as the above movable side plate relief opening window 9
By abutting against the front and rear end surfaces of 9, it is supported so that it can slide only in the left and right direction. The upper surface of both ends of the spacer guide 92 in the longitudinal direction ζ is the tray mounting piece 98
A boss 104, 104 having tray support surfaces 92a, 92a of the same height as the tray support surface 988, 98a of 98° is provided protrudingly, and a boss having a lower height than these is provided between these bosses 104, 104. 105 is provided protrudingly. At the center of the support surfaces 92a, 92a of the spacer guide 92, there is a screw hole through which the threaded portion of the mounting screw 97°97 passes through the screw portion insertion hole 101, 101 drilled on the left side of the trays 94, 95. 106°106 are drilled. The threaded portion of the mounting screw 97°97 passes through the threaded member passage hole 106, 106 of the spacer guide 92, and then passes through the threaded member common slit 100, 100 of the base 25. Screw hole 102.1
It is ordered to be screwed onto 02.

Further, a threaded part insertion hole 107 is bored in the center of the boss 105 of the spacer guide 92, and the threaded part of the mounting screw 96 inserted through this threaded part insertion hole 107 is inserted into the movable side plate relief opening window 99. It penetrates and is screwed into a screw hole 102 bored in the longitudinal center of the presser plate 93 located on the lower surface side of the base 25. Then connect the spacer guide 92 and presser plate 93 via the mounting screws 96, slide them together to match the size of the trays 94, (95), and then attach the trays 94. (95
) to the base 2 via the mounting screws 96, 96, 97.97.
It will be installed integrally with 5.

Further, as shown in FIG. 9, the trays 94 and 95 are provided with a hole 109 into which a detection portion is inserted, facing the detection portion 108al of the detection lever 108 of the paper presence/absence detection mechanism 61 for the lower stage. Friction plates 11θ and 110 are provided on the upper surface of the end side in the copy paper take-out direction where the cut-in hole 109 is formed.
is pasted.

As shown in detail in FIG. 9, the paper presence/absence detection mechanism 61 for the lower stage includes a detection lever 108, a detection lever holding member 111,
Switch actuation lever 112, paper presence/absence detection switch 113
It is configured with the following. The detection lever 10B is formed by bending the right end portion of a rigid wire, and is rotatable by passing the integrated support portion 10B,' through the support hole 111a, Izla of the detection lever holding member III. Retained. The detection lever 10B is formed by once bending the right end of a wire at a right angle, and then further bending this tip into a shim shape to form a detection portion 108a. A switch actuation lever 112 is located at the left end of the support shaft portion 1081.
is attached, and the actuator pressing surface 112a of this switch operating lever 112 is connected to the paper presence/absence detection switch 1.
13 actuators 113a+ are in contact with each other. Note that the arrow shown in FIG. 9 indicates the paper feeding direction of the copy paper P1.

However, as shown in FIG. 1O (a), when the paper feed tray 13 is located at the lower position or when all the copy sheets P1 are taken out and the detection part 108a of the detection lever 10B is at the lower limit position. , the paper presence/absence detection switch 113 is OFF.
state, and a paper-out signal is obtained.

Further, the paper feed table 13 rises and the uppermost copy paper P1 comes into contact with the detection portion 108a of the detection lever 108 and is pushed up, and the detection lever 108 begins to rotate about the support shaft portion 108', As shown in the figure, the paper presence/absence detection switch 113 is turned on a little before the copy paper P1 contacts the paper feed roller 85, and a signal indicating presence of paper is obtained. Note that the detection lever 1θ8 detects that the uppermost copy paper P1 is connected to the paper feed roller 85.
The ONL rotates until it comes into contact with the sheet with an appropriate pressure and becomes ready to feed paper as shown in FIG. 10 (c).

Further, as shown in FIG. 11, the detection portion 108a of the detection lever 108 is formed with a stopper portion 108C that is perpendicular to the axis of the detection lever main body 108b. Then, when copying paper P1... is set, a replenishment amount limiting stopper 153 that stops excess copying paper P,... exceeding a certain amount h1 from being received by the stopper portion 108C of the detection lever, and prevents further entry. It consists of Therefore, the copy paper P1 that can be set with the paper feed roller 85.
・At least a necessary gap will be secured between.

Further, the paper presence/absence detection mechanism 62 for the upper stage includes a detection lever 114, a detection lever holding member 71, and a detection lever holding member 71, as shown in detail in FIG.
5, 115. The configuration includes a switch actuation lever 116 and a paper presence/absence detection switch 117. The detection lever 114 is made by molding the right end of a rigid wire using the same mold as the lower detection lever 10B, and is used by inverting it so that the front and back directions are reversed. The integrated support shaft portion 114' is rotatably held by passing through the support holes 115a, 115a of the detection lever holding members 115, 115. The detection portion 114a of the detection lever 114 engages with the drive shaft 47 of the upper paper ejection mechanism 43.
This allows it to move up and down within a certain range. A switch operating lever 116 is attached to the left end of the support shaft 114', and an actuator pressing surface 116a of the switch operating lever 116 is in contact with an actuator 117a of a paper presence detection switch 117. As shown in FIG. 13, if the paper feed cassette 15 is not set or if there is no copy paper P even if the paper feed cassette 15 is present, the detection lever 114
The detection unit 114a is at the lower limit position as shown in FIG. 13(A), and the paper presence detection switch 117 is turned OFF.
It becomes an F-shaped track and a signal indicating no paper is obtained. In addition, if there is copy paper P in the paper feed cassette 15, copy paper P
2, the detection part 114a of the detection lever 114 is
As shown in the figure (bl), it is pushed up,
The paper presence/absence detection switch 117 is turned on and a resistance signal is obtained.

Note that the arrow in FIG. 12 indicates the feeding direction of the copy paper P.

In addition, as shown in FIG. 14, the paper support plate 118 that supports the front lower surface of the copy paper P stored in the paper feed cassette 151 is pushed up by a push-up lever ring 119 that is constantly biased. It is pushed up via a lever 60. Then, the uppermost copy paper P2 is brought into contact with a paper feed roller 120 attached to a drive shaft 47 forming a paper take-out mechanism 42 with appropriate pressure. The push-up lever 60 is inserted into the bottom plate 15 through an opening 121 formed in the bottom plate 15a of the paper feed cassette 15.
It has a structure that can be freely projected and retracted from the upper surface side of a. In addition, 12
Reference numeral 2 denotes a detection part depression hole formed in the upper paper support plate 118 corresponding to the detection lever 114 of the paper presence/absence detection mechanism 62 for the upper stage.

Further, when the elevator type paper feeding device 11 detects that the cover 9 is opened by the ON/OFF signal from the open/close detection switch 18, the paper feeding tray 13 is moved to the paper replenishing position, that is, the lower limit. When it is detected that the cover 9 is closed, the paper feed table 13 is raised to a position where paper can be fed.

On the other hand, in conjunction with the movement of the paper feed tray 13 accompanying the opening and closing of the cover 9, the means for pushing up the paper support plate 118 of the paper support temporary push-up type paper feed device 12 is automatically turned on and off. It becomes. That is, while the paper feed table 313 is lowered by about 12 mx (about 1 second) when the cover 9 is opened, the push-up lever mounting shaft 123 rotates by a predetermined amount, and the push-up lever 6θ moves as shown by the solid line in FIG. It is rotated from the position to the two-dot chain line position and is separated from the paper support plate 118. Then, the paper feed cassette 15 is made ready for removal. When the cover 9 is closed and the paper feed table 13 is raised by about 12 ma, the push-up lever 60 is rotated from the two-dot chain line position to the solid line position, and the push-up lever 60 applies an impact to the paper support plate 11B. It is designed to push up without giving away. Then, it is made into a shape that can feed paper.

This paper support plate push-up/release mechanism 59 will be described in detail based on FIGS. 15, 16, and 17. The paper support plate push-up/release mechanism 59 includes a push-up lever 60 as a push-up means;
The push-up lever operating mechanism 124 rotates and deflects the push-up lever 60. The push-up lever 60 is attached to the left and right frames 20, 21 with bushes 125, 125 (
The front end side is fixed to a push-up lever mounting shaft 123 which is rotatably suspended horizontally via a push-up lever mounting shaft 123 (only the right side is shown), and a guide roller 126 is provided at the free end for smooth contact and separation with the paper support plate 118. It is rotatably mounted. The right end of the push-up lever mounting shaft 123 protrudes toward the outer wall surface of the right frame 21, and is connected to the first spring locking lever 127 and the second spring locking lever 12.
The gears 129 integrally having the gears 8 are fitted in sequence, and are prevented from falling off by the locking ring 130. A pin 133 is inserted into the shaft fitting portion 127a of the first spring locking lever 127 so that its tip engages with a pin engagement R1321 formed on the push-up lever mounting shaft 123, and the two are integrated. It becomes.

The first spring locking lever 127 is formed in an inverted shape, and the vertical piece 127b has the spring 1 for the push-up lever.
One end of the lever 19 is connected, and is always urged to rotate clockwise in the shape cap shown in FIGS. 16 and 17, so that the push-up lever 60 is at the position shown by the two-dot chain line in FIG. ing. In addition, the first spring locking lever 12
The tip of the horizontal piece portion 127c extending rearward of 7 is bent outward at right angles, and the pressing force receiving surface 1 consisting of this upper end surface
34 comes into contact with a pressing force transmission surface 135 formed by the lower end surface on the free end side of the second spring locking lever 12B.

On the other hand, a driven shaft 136 is provided above the right end of the push-up lever 123 in parallel thereto. This driven shaft 136 has a bushing fitting hole 138.13g drilled in the right frame 21 and the subframe 137 mounted parallel thereto.
It is rotatably suspended horizontally through bushings 139, 139 fitted to the . The driven shaft 136 is fitted with the upper sprocket 261 hub 140 and the variable gear 141 that meshes with the gear 129 in this order. The upper sprocket 26 and the hub 140 are fixed to the driven shaft 136 via pins 133, 133, and the hub 140 has a power transmission spring 142 wound in a coil.
is fitted externally. One end locking part 1 of power transmission spring 142
42a projects in a direction perpendicular to the axial direction and can be engaged with the lower surface of the engagement pawl 143 formed integrally with the subframe I37#; the other end engagement portion 42a projects in the axial direction; 142b is always engaged with the engagement groove Z44 of the variable gear 141. Note that 145 is a return spring that always urges the second spring locking lever 128 to return to a predetermined position. Further, 146 is a tension adjustment mechanism that adjusts the tensile force of the push-up lever spring 119. This tension adjustment mechanism 146 is fixed to the right frame 21 and serves as a guide shaft 1 that also serves as a mounting shaft for the subframe 137.
471 Guide block 148 slidably attached via guide shaft 147, this guide block 14B
a connecting member 149 that is held by the push-up lever spring 119 and to which the other end of the push-up lever spring 119 is locked; and a guide block 14
8 and an adjustment screw 150 whose distal end surface is in contact with the circumferential surface of the guide shaft 147. By tightening or loosening the adjustment screw 150, the movable block 148 is moved backward or forward, and the tension of the push-up lever spring 119 is adjusted.

Therefore, when the paper feed tray 13 is lowered with the opening operation of the cover 9, the right endless chain 30 runs in the direction of the solid arrow, and the sprocket 26, hub 140, and driven shaft 136 move clockwise. The power transmission spring 142 rotates to the hub 14 due to frictional force.
0, and the driving force of the hub 140 is transmitted to the variable gear 141 via the power transmission spring 142.

Then, one end of the power transmission spring 142 is driven open until the locking portion 142a contacts the locking pawl 143 and the tightening force is released. The driving force of the variable gear 141 is transmitted to the gear 129 that meshes with the variable gear 141, and the second spring locking lever 128, which is integral with the gear 129, rotates counterclockwise against the biasing force of the return spring 145. Therefore, the pressing force transmitting surface 135 of the second spring locking lever 128 pushes the pressing force receiving surface 134 of the first spring locking bar 127, and the first spring locking lever 127 pushes the push-up lever spring 119. It rotates 1 in the counterclockwise direction against the biasing force of , and changes from the solid line type in FIG. 17 to the two-dot chain line type 4. The push-up lever 60 is in an integral relationship with the first spring locking lever 127.
is rotated from the two-dot chain line position in FIG. 16 to the solid line position and from the solid line position in FIG.
make it free. On the other hand, after the tightening force of the power transmission spring 142 is released, the sprocket 26. hub 140,
Only the driven gear 136 will rotate.

At this time, the other end locking portion 142b of the power transmission spring 142 engaged with the engagement @144 of the variable gear 141 is shown in FIG.
From the state shown in A) to the state shown in FIG.

Furthermore, when the paper feed table 13 rises with the closing operation of the cover 9, the sprocket 26, the hub 140 and the driven shaft 1
36 rotates counterclockwise, and with this rotation, the power transmission spring 142 and variable gear 141 rotate integrally. When the other end IE portion 142b of the power transmission spring 142 reaches the position shown in FIG. 18(a), the power transmission spring 142
The frictional force disappears, and the hub I40, sprocket 26,
Only the driven shaft 136 rotates, and the variable gear 141 and the gear 129 meshing therewith stop rotating. therefore,
The second spring locking lever 12 & integral with the gear 129
Then, the first spring locking lever 127 is rotated to the position indicated by the two-dot chain line in FIG. 17. and,
The push-up lever 60, which is in an integral relationship with the first spring locking lever 127, is rotated from the solid line position in FIG. 16 to the two-dot chain line position and from the two-dot chain line position in FIG. 4 to the solid line position, The paper feed cassette 15 is made ready for paper feeding.

The lower limit detection mechanism 39 includes a pin 151 protruding from the rear of the left end surface of the paper feed table 13 as shown in FIG. It consists of

Next, the operation of the above embodiment will be explained with reference to FIG.

First, when the cover 9 is closed, the cover opening/closing detection switch 1
8 is turned ON, and the chain drive mechanism 3 of the paper feed table operating mechanism 41
8 reversible electric motor 34 drives the endless chain 29.3
0 travels in the positive direction (in the direction of the solid line arrow in Figure 3) and reaches the paper feed tray I.
3 rises. When the detection lever 10B of the paper presence/absence detection mechanism 61 for the lower stage is pushed up by the uppermost copy sheet P8, the paper presence/absence detection switch 113 is turned on to detect the existence of paper. Furthermore, when the paper feed table 13 is raised and the paper feed rollers 85 and 85 of the paper feed roller unit (70°72) are pushed up, the upper limit detection switch 91 of the upper limit detection mechanism 40 is turned on and the reversible motor 34 is stopped. The raising of the paper feed tray 13 is stopped, and the elevator type paper feed device #11 enters a standby state in which paper can be fed.

On the other hand, as described above, as the paper feed table 13 moves upward, the paper feed cassette 15
The paper support plate 118 is pushed up by the push-up lever 60 and becomes in a standby state where paper can be fed.

Next, with paper feeding from the elevator type paper feeding device 11 specified, the print button 3 is pressed to turn on the first electromagnetic clutch 53 of the paper feeding roller drive mechanism 45, which drives the paper ejecting mechanism 42 for the lower stage. The driving force of the endless chain 51 is transmitted to the shaft 46, and the uppermost copy paper P1 is taken out as the paper feed rollers 85... rotate and guided to the restart paper feed roller 44 side, and then The electromagnetic clutch 57 of No. 3 is turned on at the right timing, and the paper feed roller 44 rotates, thereby feeding the paper.

In this way, copy paper P1. ... are sequentially taken out, the paper feed roller 85 ... descends, and the upper limit detection mechanism 40
The upper limit detection switch 91 is turned OFF, and the paper feed tray 1
3 rises again. Then, the intermittent movement of the paper feed tray 13 is repeated so that the uppermost copy paper P1 is located within a certain paper feed range. When all the copy sheets P1 are fed, the detection portion 108a of the detection lever 10B of the paper presence/absence detection mechanism 61 detects the tray 94 of the paper feed tray 13. (95) Detection part drop hole 10
9, the paper presence/absence detection switch 113 is turned off, and a paper out display (empty display) is displayed on the display section 5 of the operation panel 6.

On the other hand, if you press the print button while specifying paper feeding from support plate push-up type paper feeding device #12, the paper feeding roller drive mechanism 4
The second electromagnetic clutch 54 of No. 5 is turned on, and the driving force of the endless chain 51 is transmitted to the drive shaft 47 of the upper paper take-out mechanism 43, and the uppermost copy paper P is fed to the paper feed roller 120... The third electromagnetic clutch 57 is turned on at the right timing, and the third electromagnetic clutch 57 is turned on at the right timing to remove the paper from the feed roller 44 for restarting.
The paper is fed by the rotation of the paper. In this way, the copy paper P.

When the inside of the paper feed cassette 15 becomes empty by sequentially taking out the paper, the detection part 114a of the detection lever 114 of the paper presence/absence detection mechanism 62 falls into the detection part drop hole 122 formed in the paper support plate 11B and detects the presence or absence of paper. Detection switch 117 is OFF
F, and a paper out message is displayed on the display section 5 of the operation panel 6.

In this way, when the paper out display is displayed on the display section 5, the operator opens the cover 9 and prints the copy paper P...
Alternatively, P, . . . will be replenished. first,
When the cover 9 is opened, the cover opening/closing detection switch 18 is turned to O.
The chain drive mechanism 3 of the paper feed table operating mechanism 41 becomes FF.
The reversible electric motor 34 of No. 8 rotates in the reverse direction, the endless chain 29.degree. And the lower limit position detection switch 152
The actuator 152a is connected to the pin 1 integrated with the paper feed table 13.
51, the reversible electric motor 34
stops, and the paper feed table 12 stops at the lower limit position. On the other hand, as described above, as the paper feed table 13 is lowered, the push-up lever 6o that pushes up the paper support plate 118 of the paper feed cassette 15 in the support plate push-up type feeder device 12 is moved as shown by the two-dot chain line in FIG. The paper feed cassette 15 is rotated to the position and becomes free.

As a result, the copy sheets P1, . After completing these operations, the above operations will be automatically performed by closing the cover 9.

Also, when replenishing the copy paper P1... onto the paper feed table I3, the stopper portion 108C of the detection lever 108 of the paper presence/absence detection mechanism 61 causes the amount exceeding the upper limit, that is, the amount exceeding the glue in FIG. The replenishment of paper is physically restricted, and inconveniences such as folding of the leading edge of paper due to excessive replenishment can be reliably prevented.

Further, the paper feed roller unit 70.72 of the paper take-out mechanism 42 for the lower stage is vertically movable with respect to the arm 73 as shown in FIG. Because it has a structure that can tilt with the central part as a fulcrum, it is possible to tilt downwards to the right (as shown in Figure 5-19, for example, to make it easier to understand). Even if the state is the same, all paper feed rollers 85 and
... comes into contact with the copy paper P, ... with reliable and uniform force, and a constant conveying force is obtained, and the copy paper P1°0.
can be taken out very well.

Further, the paper feed tray operating mechanism 4I is composed of a chain drive mechanism 38, an endless chain 29, 30 and a sprocket 26.
Since the sheet feeding table I3 is raised and lowered by engaging with the sheet feeding table 27, the sheet feeding table 13 can be positioned at a predetermined position without slipping.

Furthermore, endless chains 29, . Since the hooks 90 face each other with both sides of the paper feed table 13 sandwiched between them, the paper feed table 13 does not swing laterally when going up and down, allowing stable up and down movement.

〔Effect of the invention〕

As explained above, the present invention partially engages with the paper feed tray,
In addition, since it is equipped with an endless chain (equipped with interlocking sprockets and a motor that can rotate forward and backward to drive the sprockets) that extends along the vertical direction of the paper feed table, the paper feed table can be prevented from slipping. This has the effect that it can be raised and lowered without causing any problems, and that it can be accurately positioned and held at a predetermined position, and that good sheet feeding performance can be maintained.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is an external perspective view of the entire copying machine, FIG. 2 is a perspective view with the cover covering the exposed part of the paper feeder opened, and FIG. FIG. 4 is a perspective view schematically showing the structure of the paper feeder unit. FIG. 4 is a perspective view showing the structure around the paper ejecting mechanism of the elevator type paper feeder. @Figure 5 is an exploded perspective view of the paper feed roller unit, Figure 6 (A), (Of is a partially longitudinal front view for explaining the installation state of the paper feed roller assembly and arm, and Figure 7 is a ,(of
is a schematic side view for explaining the configuration of the detection part of the upper limit detection mechanism, Figure 8 is an exploded perspective view of the paper feed tray, Figure 9 is a perspective view showing the paper presence/absence detection mechanism for the lower stage, and Figure 1O. (stomach),(
Mouth 1. (C) is a schematic side view for explaining the detection operation of the paper presence/absence detection mechanism, FIG. Perspective view showing the paper presence/absence detection mechanism for the upper stage, No. 13
Figures (A) and (B) are schematic side views for explaining the detection operation of the paper presence/absence detection mechanism, and Figure 14 is a schematic vertical side view showing the relationship between the paper feed cassette and the support plate push-up lever. 1st
Figure 5 is a partially cutaway plan view of the support plate push-up/release mechanism, Figure 16 is a schematic exploded perspective view of the support plate push-up/release mechanism, and Figure 17 is a front view of the main parts. Figure, 1st
Figure 8 (Il, (Ol) is also an explanatory diagram to explain the relationship between the variable gear and the power transmission spring, which are the main parts, and Figure 19 (Pi 1 to 1) shows the contact state between the paper feed roller and the copy paper. It is an explanatory diagram for explaining. P, , P, . . . Paper (copy paper), I3 . . . Paper feed table, 42 .
0... Endless chain, 26, 27. 28... Sprocket, 34... Motor (reversible electric motor). Figure 1 Figure 2 Figure 6 (A) 0 (B) Figure 7 (A) (B) Figure 18 Figure 19 199-

Claims (2)

[Claims] (1) A paper feed tray that moves up and down with paper placed on it, and a take-out means for taking out the paper placed on this paper feed tray, in which a portion of the tray engages with the paper feed tray, and A paper feeding device comprising: a sprocket that meshes with an endless chain that extends along the direction in which a paper table moves up and down; and a motor that can rotate in forward and reverse directions to drive the sprocket. (2) The endless chain includes a first chain that engages with a part of the paper feed tray on one side of the paper feed tray, and a second chain that engages with a part of the paper feed tray on the other side of the paper feed tray. 2. The paper feeding device according to claim 1, wherein the first and second chains are arranged opposite to each other with the paper feeding platform sandwiched therebetween.