JPH027461B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sheet feeding apparatus such as a copying machine, and more particularly to a sheet feeding apparatus that mechanically interlocks and accurately controls the timing of starting sheet feeding.

Conventionally, in this type of sheet feeding device, when the photosensitive drum occupies a certain rotational position in order to align the relative position of the image formed on the photosensitive drum and the conveyed sheet in the transfer section, In order to feed the sheet toward the photosensitive drum in a timely manner, a micro switch detects the phase of the rotating body that rotates in synchronization with the photosensitive drum, and the solenoid of the clutch of each sheet feeding means is activated in response to the signal generated by the micro switch. was operating. However, because the response time from when the microswitch generates a signal to when the solenoid actually operates varies, it was not possible to expect the sheet feeding operation to be performed at accurate timing.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a sheet feeding apparatus such as a copying machine that can perform sheet feeding operations at accurate timing.

Another object of the present invention is to provide a sheet feeding apparatus such as a copying machine that controls the start of sheet feeding by mechanically interlocking the movement of the document scanning system.

The configuration of the present invention that can achieve the above object includes: a feeding device that feeds a sheet; and a feeding device that abuts the leading edge of the sheet fed by the feeding device to prevent the sheet from progressing, thereby ensuring timing. registration means for further feeding the sheet; feeding clutch means for controlling operation of said feeding means; registration clutch means for controlling operation of said registration means; and moving for optical scanning of a document. a scanning member; and a clutch control lever movable between a first position for actuating the feed clutch means and a second position for actuating the registration clutch means; A sheet feeding device for a copying machine, etc., characterized in that the clutch control lever is configured to move between a first position and a second position in mechanically interlocked manner.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

First, an embodiment of a copying machine to which the present invention can be applied will be described. In FIG. 1, reference numeral 1 denotes a document placement table, which is made of a transparent member and has a document placement section and is a scanning member that moves for optical scanning of the document, and is capable of reciprocating in the direction of the arrow. Reference numeral 2 denotes a converging light transmitting member which slit-exposes the original image on the original table 1 onto a photosensitive drum 3 rotating in the direction of the arrow. A charger 4 charges the photosensitive drum 3 uniformly.
Reference numeral 5 denotes a developing device, and an electrostatic latent image of the document is formed on the uniformly charged photosensitive drum 3 via the focusing light transmitting member 2, and is visualized by the developing device 5. On the other hand, the transfer paper P is fed onto the drum 3 by a paper feed roller 6 as a feeding means and a register roller 7 as a registration means which rotates in synchronization with the image on the photosensitive drum 3, and is charged for transfer. The image on the drum 3 is transferred by the device 8, and then the transfer paper is separated from the drum 3 by the separating device. After being guided to the guide 9, the toner image on the transfer paper P is transferred to the transfer paper by the fixing device 10. The image is fixed, then conveyed by the ejection roller 11, and ejected onto the tray 12.

Next, the document table moving section will be explained with reference to FIG.

13 is an original pressure bonding plate, and a transparent original mounting table 1
It has the role of holding down the original placed on it, and in this embodiment, it is made of an integral board made of polypropylene that also serves as a hinge part 13', and a white paper is attached to it through a sponge-like cushion. A pressure _- bonding sheet ₁₃ '' is attached. Reference numeral ₁₄₁ denotes an original mounting plate mounting member made of a plastic material such as polycarbonate or Juracon. The document mounting table mounting member 14 ₁ has a rack 14 ₄ that connects the document mounting table drive gear 1 on the main body side.
5, the original table 1 can reciprocate.

Next, the relationship between the document table reciprocating mechanism and the feeding mechanism according to the present invention will be explained. In FIGS. 3 and 4, a groove 16 is provided on the rear surface of the document mounting table mounting member 14 ₁ along the moving direction of the document table, and the groove 16 has two rows of grooves 16 ₁ , 16 ₂ . are lined up in parallel and join at both ends 16 ₃ and 16 ₄ . The groove 16 ₁ is further provided with a deep groove portion (detection portion) 16 ₅ in a part thereof to form a cam shape. Further, a pin 17 is engaged with the groove portion 16.
is capable of swinging around a shaft 18. Further, the fixed position of the shaft 18 can be changed back and forth by a fixed amount by one end ₁₉₁ of the lever 19 for timing adjustment. The lever 19 swings about a shaft 20 and is urged by a spring 21 to rotate counterclockwise. An engagement adjusting plate 22 is in contact with one end 19 ₁ of the lever 19 and an opposite end 19 ₂ of the lever 19 . The position of the engagement adjustment plate 22 can be adjusted by swinging around a shaft 24, and is fixed to the clutch control lever 25 by a screw 23. Clutch control lever 25
is pivotable about a shaft 26, and a clockwise rotational force is applied by a spring 27. The clutch control lever 25 is provided with pawls 28 and 29 protruding from mutually opposite sides, and the pawl 28 is normally engaged with the pawl wheel 3.
It meshes with 0. When the clutch control lever 25 is rotated counterclockwise, the pawl 28 is disengaged from the ratchet wheel 30 and the pawl 29 is in a position where it engages with the ratchet wheel 31.
The ratchet wheel 30 is coaxial with the feeding roller, and the ratchet wheel 31 is coaxial with the registration roller.

FIG. 5 is a plan view showing the positional configuration of the paper feed roller 42 and registration roller 46. 30 in the figure,
31 is a ratchet wheel, 32 and 33 are clutch drums, 3
4 and 35 are clutch springs; 36 and 37 are paper feed roller drive gears and lower registration roller drive gears; 3
Reference numerals 8 and 39 denote a paper feed roller shaft and a registration roller shaft, respectively, and 32 and 38, 33 and 39 rotate substantially as one unit. The structure and operating principle of the spring clutch as a clutch means are generally well known, but since both the paper feed roller 42 and the registration roller 46 are the same, the structure and operating principle will be explained using the spring clutch of the registration roller 46 in the sixth section. This will be explained using figures. Registration roller drive gear 37
is rotatable with respect to the registration roller shaft 39, and the outer diameter of the boss portion ₃₇₁ is slightly larger than the inner diameter of the clutch spring 35, and one end ₃₅₁ of the clutch spring 35 is wrapped around the clutch spring ₃₇₁ . Clutch spring 35 rotates 37 (direction indicated by arrow)
The control claw is wound in the direction of the winding direction.
_A1 is fitted into the cut groove _A2 of the ratchet wheel 31.
The clutch drum 33 is substantially integrated with the registration roller shaft 39 by screws etc., and the outer diameter of the boss portion ₃₃₁ is also the same as the clutch spring 3.
The other end 35 ₂ of 35 is wrapped around a diameter larger than the inner diameter of 5 .

Now, the roller drive gear 37 is rotating in the direction of the arrow. When the pawl 29 is disengaged from the ratchet wheel 31, the rotation of the gear 37 releases the clutch spring 35.
is the boss part ₃₇₁ of the gear 37 and the clutch drum 3.
The drive is transmitted to the clutch drum ₃₃ , and the registration roller shaft 39, which is substantially integral with the clutch drum 33, and the registration roller 46, which is integral with the clutch drum 33, rotate. The ratchet wheel 31 is also rotated by the control pawl _A1 of the clutch spring 35.

Now, when the pawl 29 engages with the pawl wheel 31, the pawl wheel 31
stops, and the clutch spring 35 is released by the groove _A2 .
control claw _A1 is fixed. Then, the end portion 35 ₁ of the clutch spring wrapped around the boss portion 37 ₁ of the gear 37 is loosened, the connection is released, and the registration roller stops.

The relationship between the paper feed roller 42 and the spring clutch is exactly the same. Incidentally, as shown in FIG. 5, the paper feed roller 42 and the paper feed roller shaft 38 are connected via a one-way clutch using a spring 41. That is, when the paper feed roller shaft 38 rotates in the direction of the arrow, the clutch drum 40 that is substantially integral with it also rotates, the clutch spring 41 wraps around the paper feed roller support shaft 43, and the paper feed roller 42 rotates in the direction of the arrow. However, even if the paper feed roller 42 is rotated in the direction of the arrow, the spring 41 is loosened, so the paper feed roller shaft 3
Drive is not transmitted to 8.

Next, the principle of operation of the paper feeding device of the present invention will be explained. When the main switch (not shown) is turned on,
The document table moves to the document exposure start position. At this time, as shown in FIG.
It is in position ₃ . Further, the registration roller drive gear 37 and the paper feed roller drive gear 36 are rotating in the direction of the arrow. At this time, the pawl 28 is engaged with the paper feed pawl wheel 30, and the pawl 29 is disengaged from the registration pawl wheel 31, so the paper feed roller 42 is stopped and the registration roller is rotating.

When a copy button (not shown) is pressed, the original platen begins to move and expose the original. When the deep groove portion 16 ₅ of the groove 16 ₁ comes to the position of the pin 17, the lever 19 is rotated counterclockwise about the shaft 20 by the bias of the spring 21. Then the end 19 ₂ of the lever 19
However, by pushing the engagement adjustment plate 22 and rotating the lever 25 counterclockwise, the pawl 28 is disengaged from the ratchet wheel 30 and the pawl 29 engages with the ratchet wheel 31. When the ratchet wheel 30 is released, the paper feed roller 42 rotates and feeds the transfer paper P into the copying machine. At this point, the pawl 29 is engaged with the ratchet wheel 31, so the registration roller 46 is stopped. Therefore, the leading edge of the transfer paper P hits the pair of registration rollers 46 and 47 and is stopped, so that the transfer paper is bent to form an arched loop. This corrects the transfer paper whose leading edge has progressed obliquely to the photosensitive drum so that it is parallel to the photosensitive drum.
Wait until the leading edge of the image on the photosensitive drum is at the desired position.

When the deep groove part ₁₆₅ passes the position of the pin 17,
The pin 17 is pressed again by the groove ₁₆₁ , and the lever 19 returns to its original position. Then lever 2
5 is rotated clockwise by the spring 27 and returns to the initial position, the pawl 29 is disengaged from the ratchet wheel 31, and the pawl 28 engages with the ratchet wheel 30. When the ratchet wheel 31 is released, the registration roller 46 rotates again, while since the ratchet wheel 30 is fixed, the drive of the paper feed roller 42 is cut off and the paper feed roller shaft 38 is stopped.

Here, the transfer paper P is in contact with the paper feed roller 42, and the paper feed roller 42 is rotated as the transfer paper P advances, but in this case, the rotation is in the direction that the one-way clutch 41 is disengaged, so it is driven and there is no problem. .

As described above, the start point 16 ₆ of the deep groove portion 16 ₅ determines the time to start feeding the paper, and the end point 16 ₇ determines the time when the registration roller 46 starts feeding the paper again. Therefore, the amount of paper loop created when the leading edge of the transfer paper is stopped by the registration roller 46 is determined by the length from the deep groove starting point 16 ₆ to the deep groove ending point 16 ₇ , and the position of the leading edge of the image on the transfer paper is: It is determined by when the pin 17 reaches the deep groove end point ₁₆₇ .

This fine adjustment can be made by moving the position of the pin 17 back and forth.

Furthermore, the engagement between the pawls 28 and 29 and the ratchet wheels 30 and 31 can be adjusted by adjusting the angle of the adjustment plate 22.

When the movement of the document table progresses and the end 16 ₄ of the groove 16 ₁ comes to the position of the pin 17, the pin 17 swings along the groove and moves from 16 ₁ to 16 ₂ . When the document table moves backward, the pin 17 passes through the groove ₁₆₂ . Since the groove ₁₆₂ is not provided with a deep groove portion, there is no paper feeding operation. When the end of the groove 16 ₂ comes to the position of the pin 17, the pin 17 swings along the groove, and from 16 ₂ to 1
6 Move to ₁ and prepare for the next copy operation.

As described above, the present invention mechanically interlocks the movement of the document scanning system to control the start of sheet feeding of the sheet feeding means, registration means, etc.
The phase of the rotary body that rotates in synchronization with the photosensitive drum is detected by a microswitch, and the solenoid of the clutch of each sheet feeding means is activated in response to the signal generated by the microswitch.The response performance is more accurate with no variation compared to the previous method. It is possible to control the sheet feeding start timing.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of a copying machine to which the present invention can be applied, FIG. 2 is a cross-sectional view showing a document table moving part thereof, and FIG. FIG. 4 is a sectional view thereof, FIG. 5 is a sectional view showing the paper feed roller and registration roller portion, and FIG. 6 is an exploded view of the clutch mechanism of the registration roller. In the figure, 16 is a groove portion, ¹⁶⁵ is a deep groove portion (detection portion), 17 is a pin, 19 is a lever, 25 is a clutch control lever, 28 and 29 are pawls, 42 is a paper feed roller, and 46 is a registration roller.

Claims (1)

[Scope of Claims] 1. A feeding means for feeding a sheet, and a feeding means for stopping the advance of the sheet by coming into contact with the leading edge of the sheet fed by the feeding means, and further feeding the sheet at a timing. a feeding clutch means for controlling operation of the feeding means; a registration clutch means for controlling operation of the registration means; and a scanning member movable for optically scanning a document. a clutch control lever movable between a first position for actuating the feed clutch means and a second position for actuating the registration clutch means, the lever being mechanically coupled to movement of the scanning member; A sheet feeding apparatus for a copying machine or the like, characterized in that the clutch control lever is configured to move between a first position and a second position.