JPH0749491Y2 - Offline fixing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a fixing device for heating and fixing unfixed information formed on the surface of a copy sheet, and is particularly installed independently from the copying device and installed separately. Offline fixing device.

[Conventional technology]

Generally, in this type of fixing device, when a paper jam occurs in a conveyance path of copy paper (hereinafter, referred to as paper), the paper is burned by the heat of the heating device. On the other hand, there is a paper jam sensor provided in the center of the transport path to stop the operation of the device when a paper jam occurs. When he jammed the paper, he could not detect it.

Therefore, there has been proposed an apparatus in which a sheet position detecting unit is provided at the sheet insertion port and the sheet is not received when the sheet is not inserted from a predetermined position (for example, the central portion). This device is equipped with feed sensors at the center and edge of the paper insertion slot.When the paper is actuated at the center or at the center and the edge at the same time, the blower motor is rotated. Negative pressure is generated, the transport belt is rotated in the forward direction, and the paper is sucked and transported, and the paper is transported into the apparatus. Further, when the paper actuates only the sensor at the end of the paper due to an insertion error, the conveyance belt is reversed in response to the generation of negative pressure, and the paper is ejected from the paper insertion port. Therefore, the sheet is conveyed only when the user inserts the sheet from the predetermined position, and otherwise the sheet cannot be accepted.

[Problems to be solved by the device]

By the way, especially when using a wide paper, the user often inserts the paper obliquely with respect to the insertion slot.
In this case, since the feed sensors at the central portion and the end portions are not actuated at the same time, the paper is ejected from the paper insertion port. However, if such an insertion error such as oblique feeding is frequently repeated, the blower motor also rotates each time, and the heating device is cooled by the vacuumed air. When the heating device is cooled in this way, it is necessary to warm up until the normal fixing temperature is restored, which causes a waiting time.
Especially during warm-up, it tends to run out of warm-up, which takes even more time.

Further, for the same reason, the ambient temperature inside the apparatus main body becomes low, and there is a problem that defective fixing easily occurs.

It is an object of the present invention to provide an off-line fixing device that can achieve stable fixing without waiting time by preventing cooling of the heating device and reduction of ambient temperature inside the device body due to insertion error.

[Means and Actions for Solving the Problems]

In order to solve the above-mentioned problems, according to the present invention, an unfixed copy sheet inserted through a sheet insertion port formed along the width direction of a sheet conveyance path is sucked by a vacuum blower and conveyed to a heating unit, When outputting the copy sheet fixed by the heating unit, if the unfixed copy sheet is improperly inserted into the sheet insertion port, the unfixed copy sheet adsorbed by the vacuum blower is conveyed backward. In an off-line fixing device that returns the sheet to the sheet conveyance path and prompts re-insertion, a feed sensor that detects the insertion position and orientation of the unfixed copy sheet, and the unfixed copy based on the detection signal of the feed sensor. A control means is provided for controlling the temperature of the heating unit to be maintained at the fixing temperature while the unfixed copy sheet is conveyed in the reverse direction when the inserting position and the posture of the sheet are inappropriate. Temperature and equipment of the heating unit due to the rotation of the blower motor is to prevent a decrease in the ambient temperature in the body.

〔Example〕

An embodiment of the offline fixing device according to the present invention will be described in detail below.

FIG. 1 shows an off-line fixing device (hereinafter,
FIG. 3 is a perspective view of a main part of a fixing device) 1.

The fixing device 1 includes a heating device 3 that heats and fuses an unfixed toner image (information), a vacuum-type paper conveying device 4 that conveys a sheet to the heating device 3, and a sheet on which information is fixed. 2, a first feed sensor 21 for detecting the presence of the paper, and a second feed sensor 21 for detecting the presence of the paper at the center and both ends of the paper insertion opening 2b formed in the apparatus main body 2. The respective feed sensors 26 are provided.

Of these, the heating device 3 includes a plate heater 6 arranged below the sheet conveying path (arrow A) and a quartz heater lamp (not shown) arranged above the plate heater 6 so as to face the heater 6. The temperature is controlled by the control device described later.

The heating device 3 is normally maintained at the fixing temperature, and in order to maintain this temperature, an output of about 10% at the time of fixing is intermittently applied. That is, once the temperature is raised to the fixing temperature, the temperature can be maintained with a slight output. However, at the time of actual fixing, the heat is taken away by the paper and the vacuumed air, so 100
% Output to keep the fixing temperature. Also,
The paper on which the information is fixed by the heating device 3 is ejected to the outside of the main body 2 of the device via the ejecting device 5 including the pair of rollers 7 and 8.

On the other hand, the paper transport device 4 has a housing 9 that generates a negative pressure.
And a belt 10 wound around the peripheral surface of the housing 9 to suck and convey the sheet. The transport device 4 is disposed so as to face the front surface 2a of the apparatus main body 2, and the paper is inserted along the width direction of the paper transport path A so that the papers 11 and 12 of various sizes can be inserted into the front surface 2a. A mouth 2b is formed.

Further, a paper jam sensor 13 for detecting a paper jam is arranged at the center of the paper conveyance path A. When a paper jam occurs, the fixing device 1 operates based on the detection signal from the sensor 13. Is configured so that the sheet that caused the jam can be removed.

On the other hand, the first feed sensor 21 arranged in the central portion of the paper insertion slot 2b is a pair of photo interrupter type sensors.
The sensors 22 and 23 are arranged so as to face each other at a position sandwiching the paper jam sensor 13. The paper jam sensor 13 is installed at two locations on the paper transport device 4 and on the downstream side of the paper transport path A (behind the heating device 3), both of which are installed in the widthwise center of the paper transport path A. There is. The paper jam sensor 13 is composed of a photo-interplater type sensor 24 for detecting the presence of copy paper and a photo-pulse transmission type sensor 25 for detecting a change in the running state of the paper.

Further, the second feed sensors 26 arranged at both ends of the sheet insertion opening 2b are also constituted by photo interrupter type sensors 27 like the first feed sensor 21.

In FIG. 1, reference numeral M1 is a motor for driving the sheet conveying device 4 and the sheet discharging device 5, M2 is a vacuum blower motor for generating a negative pressure in the housing 9 of the sheet conveying device 4, The drive of each of the motors M1 and M2 is controlled by the control device described later. Further, the motor M1 and the shaft 28 supporting the one roller 7 of the paper discharge device 5 are connected by a one-way clutch 29 fixed to the shaft 28 and a belt 30 wound around the clutch 29. There is. The one-way clutch 29 transmits to the roller 7 a normal rotation of the motor M1, that is, a driving force for conveying the copied paper only to the downstream side of the paper conveyance path A. Further, reference numeral 14 in FIG. 1 denotes a stock plate for accommodating the copy paper 15 after fixing.

Next, a control device that controls the driving of the heating device 3 and the motors M1 and M2 described above will be described.

FIG. 2 is a block diagram showing a control device 40 for controlling the heating device 3 and the motors M1 and M2 described above. This controller 40
The controller 41 is composed of a CPU and a main storage device, and controls the driving of the heating device 3 and the motors M1 and M2 based on the detection signals of the first and second feed sensors 21 and 26. When only the detection signal of the second feed sensor 26 is input, the controller 41 drives the motor M1 in reverse, and at the same time, turns on the heating device 3 with an output of 50% of that at the time of fixing. By giving the output of 50%, the temperature of the heating device 3 rises, but the heating device 3 is maintained at the fixing temperature because the temperature is balanced with the vacuumed air. Further, the ambient temperature inside the apparatus main body 2 can be kept constant. Here, the output of the heating device 3 when the motor M1 is driven in the reverse direction to eject the paper is set to an output that allows the heating device 3 to maintain the fixing temperature. In this embodiment, the output of 50% at the time of fixing is set, but actually, the output may be set within the range of about 30 to 70% at the time of fixing. On the other hand, the second feed sensor 26 and the first feed sensor 21
Detection signals of the first feed sensor 21
When only the detection signal is input, the motor M1 is driven in the normal direction, that is, the paper is rotated in the direction in which the paper is transported to the downstream of the paper transport path A, and at the same time, the heating device 3 is turned on with an output of 100%.

The controller 41 drives the motor M2 to generate a negative pressure in the housing 9 shown in FIG. 1 regardless of which detection signal from the first and second feed sensors 21 and 26 is input. . Further, the detection signal of the first feed sensor 21 is
It is delivered when both the photo-interplater type sensors 22, 23 shown in FIG. 1 are actuated simultaneously.

Next, the operation of the above-described fixing device 1 will be described, and the configuration will be described in more detail.

As shown in FIG. 1, when the sheet 11 having a narrow width is inserted from the right end portion of the sheet insertion port 2b, the first feed sensor 21 is not actuated and only the second feed sensor 26 is actuated. In this case, the control device shown in FIG.
The motor M1 is driven in reverse by 40 and
M2 is driven, and at the same time, the heating device 3 is turned on with an output of 50% of that at the time of fixing. When the motor M1 is driven in the reverse direction and the motor M2 is driven in this manner, the paper 11 (shown by the one-dot chain line) inserted in the paper insertion opening 2b is transferred to the belt 10 of the paper conveyance device 4.
The belt 10 is used to feed the paper to the paper transport path A.
Will surely be pushed back upstream. Similarly, even if the copy paper 11 is inserted from the left end of the paper insertion opening 2b, the paper 11 is pushed back to the upstream side of the paper transport path A. At this time, since the heating device 3 is maintained at the fixing temperature by the output of 50% at the time of fixing, the fixing can be performed immediately when the paper discharged to the upstream side is normally inserted next time.

On the other hand, when the narrow paper 11 is inserted from the center of the paper insertion opening 2b, only the first feed sensor 21 is actuated. In this case, the control device 40 drives the motor M1 to rotate in the normal direction, drives the motor M2, and simultaneously turns on the heating device 3 with an output of 100%. When the motor M1 is driven in the forward direction and the motor M2 is driven in this manner, the sheet 11 is conveyed to the downstream side of the sheet conveyance path A while being attracted to the belt 10 of the sheet conveyance device 4, and moves above the sheet jam sensor 13. After passing, it is conveyed to the heating device 3, where the unfixed toner image is fixed by heat fusion.

Also, when a wide paper 12 is inserted, the first and second
Since the feed sensors 21 and 26 of the sheet feeding device are simultaneously actuated, the motor M1 rotates in the normal direction.
The reference numeral 10 conveys the copy paper 12 to the downstream side of the paper conveyance path A while adsorbing the copy paper 12 and passes it above the paper jam sensor 13.

Here, if the paper 12 is inserted counterclockwise from the right end portion due to an insertion error, the second feed sensor 26 is first actuated, and then the first feed sensor 21 is actuated. Therefore, the same operation as when only the second feed sensor 26 is actuated is performed, and the sheet 12 is pushed back to the upstream side. In the above embodiment, since the motor M1 and the roller 7 of the discharging device 5 are connected via the one-way clutch 29, the motor M1
When is reversed, the rotation of the roller 7 is stopped. For this reason,
The copy paper 15 once discharged to the rear of the discharging device 5 is not sucked into the discharging device 5 again.

Next, a processing procedure for controlling each motor and the heating device in the control device 40 described above will be described in more detail with reference to the flowchart of FIG.

First, the insertion state of the paper is judged by the detection signals from the first feed sensor 21 and the second feed sensor 26 (step 101). Here, the first feed sensor 21
Only the case where only the second feed sensor 26 is actuated and the case where the first and second feed sensors 21 and 26 are actuated at the same time are regarded as normal insertion, and the case where only the second feed sensor 26 is actuated (the paper is skew (Including the case where the second feed sensor 26 is first actuated, and then the first feed sensor 21 is actuated).
Is considered an insertion error.

In the case of normal insertion, the motor M1 is driven in the forward direction and the motor M2 is driven, and at the same time, the heating device 3 is turned on with an output of 100% (step 102). Next, the paper is loaded into the apparatus main body 2
Then, the toner image is fixed by the heating device 3 (step 103), and then the sheet is conveyed to the stock plate (step 104). Next, when the next sheet is not inserted within the predetermined time, the rotation of the motors M1 and M2 is stopped, the output of the heating device 3 is lowered, and normal temperature control is performed (step 105).

On the other hand, when it is determined that the insertion error occurs in step 101, the motor M1 is driven in the reverse direction and the motor M2 is driven, and at the same time, the heating device 3 is turned on at the output of 50% at the time of fixing (step 106). Next, the sheet is discharged from the sheet insertion port by the belt 10 (step 107), and when it is confirmed that the sheet is returned by the detection signals from the first and second feed sensors 21 and 26, the motor M1 , The rotation of M2 is stopped, the output of the heating device 3 is lowered, and normal temperature control is performed (step 105).

In steps 102 and 106, the driving of the motors M1 and M2 and the temperature control of the heating device 3 may be simultaneously operated, or may be sequentially operated at a predetermined timing.

Next, another embodiment of the present invention will be described.

In the fixing device in the above embodiment, the size of the heater lamp is set according to the width of the widest paper used. Therefore, when a wide sheet is inserted, there is no problem, but when narrow sheets are continuously inserted, an abnormal temperature rise may occur at both ends of the heater lamp of the heating device. Therefore, as shown in FIG. 4, the heater lamp 31 is divided into three, and is composed of a narrow width heater lamp 32 and wide width heater lamps 33 and 34. The control device 40 determines the width of the inserted sheet based on the detection signals from the first and second feed sensors 21 and 26. If the paper width is narrow, only the narrow heater lamp 32 is turned on, and if the paper width is wide, all three heater lamps 32 to 34 are turned on.

In this way, depending on the width of the paper used, the heater lamp 31
Since the unnecessary heating portion can be eliminated by changing the lighting area of, it is possible to prevent an abnormal rise in temperature at both ends even when a narrow sheet is continuously run. It goes without saying that the heating device of this embodiment can also perform the same temperature control as that of the above-mentioned embodiments.

[Effect of device]

As described above, in the off-line fixing device according to the present invention, when the unfixed copy paper has an improper insertion position and posture based on the detection signal of the feed sensor provided at the paper conveyance port, the unfixed state is undetermined. A control means is provided for controlling the temperature of the heating section to be fixed at the fixing temperature as well as the reverse transfer of the loaded copy sheet. What is the normal temperature control for the temperature of the heating section when the unfixed copy sheet is conveyed in the reverse direction? Since the temperature of the heating part is always kept at the fixing temperature by performing different forced temperature control, the heating part is cooled by cooling the heating part caused by the movement of air accompanying the vacuum caused by the rotation of the blower motor at the time of insertion error. The temperature drop is compensated and the waiting time due to warm-up can be eliminated. Also,
Since the atmospheric temperature in the apparatus main body is always kept constant, stable fixing can be obtained.

[Brief description of drawings]

1 is a fragmentary perspective view showing an off-line fixing device according to the present invention, FIG. 2 is a block diagram showing a control device, and FIG.
FIG. 4 is a flow chart showing the processing procedure of the controller, and FIG. 4 is a block diagram of a heater lamp in another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Off-line fixing device, 2 ... Device main body, 3 ... Heating device, 4 ... Paper conveying device, 21 ... First feed sensor, 26
... second feed sensor, 40 ... control device, A ... paper transport path

Continuation of the front page (56) Reference JP-A-63-106772 (JP, A) JP-A-57-158866 (JP, A) JP-A-63-157182 (JP, A) JP-A-53-76041 (JP , A) JP-A-56-81878 (JP, A) JP-A-52-117641 (JP, A) JP-A-55-137555 (JP, A) Actual development Sho-63-65645 (JP, U) JP-B 54-19786 (JP, B2) JP 59-36748 (JP, B2) JP 53-41532 (JP, B2)

Claims (1)

[Scope of utility model registration request] 1. An unfixed copy sheet inserted through a sheet insertion port formed along the width direction of a sheet transport path is sucked by a vacuum blower and transported to a heating section, and a copy fixed by the heating section. When the paper is output, if the unfixed copy paper is improperly inserted into the paper insertion port, the unfixed copy paper adsorbed by the vacuum blower is conveyed backward and returned to the paper conveyance path. In an offline fixing device that prompts re-insertion, a feed sensor that detects the insertion position and orientation of the unfixed copy sheet, and the insertion position and orientation of the unfixed copy sheet based on the detection signal of the feed sensor. And an unfixed copy sheet are conveyed in the reverse direction, and control means for controlling the temperature of the heating unit to be kept at the fixing temperature is provided.