JPS6213081Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a suction conveyance device for sucking and conveying the back side of recording paper in a recording apparatus that regenerates facsimile signals.

Conventionally, this type of suction conveyance device 3 covers the upper part of the exit side of a recording-related component 2 such as a developing device, as shown in FIG. By adopting such a configuration, as soon as the leading edge 10 of the recording paper 1 leaves the recording-related parts 2, the suction surface 4
2, and has the advantage of being able to properly guide the recording paper 1 toward the ejection port.

However, due to the distance from the blower 6, the suction force of the suction start end 31 decreases, causing the inconvenience that the leading edge 10 of the recording paper 1 comes off as shown by the broken line in FIG. 2, causing a paper jam. .

This invention is equipped with a control board in the duct that opens and closes the suction hole, and by opening and closing the suction hole according to the traveling position of the recording paper and controlling the suction force of each part, the recording paper does not come off the suction surface. A suction conveyance device is provided.

The present invention will be specifically described below based on embodiments shown in the drawings.

FIG. 1 shows an example of an electrostatic recording apparatus according to the present invention, in which a roll of recording paper 1 is moved to a recording head 12 by a guide roll 11.
lead to. The recording head 12 includes a receiving section (not shown).
The reproduced facsimile signal forms an electrostatic latent image on the recording paper 1.The recording paper 1 that has undergone this process is then separated at a predetermined position in the cutting section 13 and sent to the developing device 2. and developed. In the developing device 2, toner 21 is applied to the area to which static electricity is applied by the recording head 12 for development, and the developed recording paper is transferred to a suction conveyance device so that the developed surface 16 does not come into contact with the device. 3, the back surface is attracted and conveyed to the fixing device 14.

As shown in FIGS. 2 and 3, the suction conveyor 3 connects a suction belt 4, which has a large number of small diameter suction ports 41 on its circumferential surface, at four locations with conveyor rolls 34, 35, 3.
6 and 37, and the transport roll 3 at the upstream end of the transport path
4 is positioned above the developing device 2, and a guide roll 38 is provided at the bent portion 39 of the conveyance path to support the belt 4 from the outside, thereby forming a substantially inverted L-shape from the developing device 2 to the fixing device 14. Configure a conveyance path that bends in a direction. Further, a suction duct 5 is provided on the back side of the suction belt 4 to suck the suction port 41 from the back side.

The suction duct 5 has a substantially parallel front plate 51 and a back plate 5.
2, the top plate 51 is brought into contact with the back surface of the suction belt 4, and a plurality of rectangular suction holes 53 are provided corresponding to the sliding positions of the suction belt 4 as shown in FIG. An opening is also provided in the approximate center of the back plate 52, and by sucking the inside of the duct 5 from the back side with a blower 6, the recording paper 1 is sucked onto the conveyor belt 4 and conveyed to the downstream side. go.

A control plate 7 is arranged in the duct 5 so as to be slidable along a top plate 51. The control plate 7 is provided with opening/closing holes 71 having the same shape as the suction holes 53 on the top plate, facing the downstream and midstream suction holes among the suction holes on the top plate. A plunger of a drive device 72 is connected to the control plate 7 via a link mechanism 74, and a spring 73 is further connected to urge the control plate 7 downward.

The control plate 7 is normally lowered by a spring 73, and the opening/closing hole 71 of the control plate 7 is connected to the suction hole 53 of the duct.
It is fully opened at the same time as this to create a suction effect on the duct surface plate.

The drive device 72 is connected to the control unit 8, and in response to a control signal raises the control plate 7 against the spring, closes the downstream and midstream suction holes 53 of the top plate 51, and closes the upstream suction holes 53. The suction effect is concentrated only on the suction hole 53a.

The control unit 8 includes detectors 82, 8 such as off-coupler.
3 and 84 and a control circuit 85 that receives a detection signal from the detector and sends a control signal 81 to the drive device 72, with the first detector 82 located on the entrance side of the developing device 2 and the second detector 83 near the center of the transport path,
A third detector 84 is provided at each downstream end, and when the first detector 82 detects paper feeding, a control signal 81 is sent to the drive device 72 to close the suction hole 53. Second detector 8
3 turns off the drive device 72 when it detects paper feeding.
However, the control circuit 85 is set to return to the initial state when the third detector 84 detects the discharge of paper.

However, when the first detector 82 detects that the recording paper 1 has been fed into the developing device 2, the suction hole 53 on the downstream side is closed, and the suction force of the blower 6 acts exclusively on the upstream side. The suction force at the upstream end 31 increases.
Therefore, the recording paper 1 coming out of the developing device 2 is strongly attracted onto the conveyor belt 4, and the recording paper 1 is bent along the guide plate 15. Furthermore, when the leading edge of the recording paper 1 reaches the center of the duct, the second detector 83 is activated, the duct hole 53 is fully opened, the suction force on the midstream and downstream sides is restored, and the recording paper 1 is transferred to the fixing device 14. It is transported towards the destination.

Note that if a new recording paper is subsequently supplied before one recording paper 1 is completely ejected, the preceding recording paper blocks the suction hole 41 on the midstream or downstream side, and the control plate 7 Since it has the same effect as the control board 7
The suction force at the upstream end is maintained strongly without closing the suction hole 53.

As described above, the present invention includes a control plate 7 in the duct 5 of the suction conveyance device 3, and when paper feeding to the upstream end of the device 3 is detected, the control plate 7 controls the suction holes on the midstream and downstream sides. Since it is configured to increase the suction force at the upstream end 31 when closed, the leading edge of the recording paper 1 can be reliably sucked and transported by the transport device 3, and there is no risk of paper jams, which has excellent effects.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of an electrostatic recording device, FIG. 2 is an enlarged sectional view of a suction conveyance device, and FIG. 3 is a partially cutaway perspective view. DESCRIPTION OF SYMBOLS 1... Recording paper, 3... Suction conveyance device, 5... Suction duct, 7... Control board, 53... Suction hole.

Claims (1)

[Scope of utility model registration request] In a conveyance device that has a suction duct 5 facing the conveyance path on which a breathable endless belt 4 circulates, and applies suction force to the belt 4 to attract and convey recording paper, the duct 5 has a Of the suction holes 53, 53, 53 opened in the duct wall facing the belt 4, a control board 7 is provided to open and close the suction holes from the midstream side to the downstream side. A suction conveyance device for a recording device that is connected to a drive device 72 that opens and closes a suction hole 53 based on a signal from a detector that detects the presence or absence of the suction hole.