JPS5882939A - Jam detector - Google Patents

Abstract

PURPOSE:To aim at preventing a jam detector from erroneously actuating, by providing a circuit for judging the passing of the leading or trailing edge of a moving member on a means for detecting the moving member, and as well by delaying the responsive action by a predetermined time period even if the detecting means is actuated. CONSTITUTION:There are provided a first detecting means S1 arranged in the inlet of a moving path, for detecting a sheet, an integral circuit I removing error signals for the trailing edge of the sheet, delivered from the first detecting means S1 and a first timer T1 which starts time limiting operation upon receiving a signal for the trailing edge of the sheet. Further, there are provided a second detecting means S2 arranged in the outlet of the moving path, a second timer T2 which starts time limiting operation upon receiving the leading edge of the sheet, a first judging circuit D1 which issues an output signal when the detecting means S2 does not detect the leading end of the sheet in a predetermined time period determined by the first timer T1, and a second judging means D2 which issues an output signal when the detecting means S2 does not detect the trailing edge of the sheet in a predetermined time period determined by the timer T2. Further, there is provided means G for generating a jam signal in association with the outputs of the judging means D1, D2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying material, copying material, etc.O moving member O/Yam photocopying meeting meeting equipment. With a copier WctIk etc. that can print multiple sheets without much effort, autofeed prevents jams. Conventionally, to detect paper in copying machines, the Japanese Patent Publication No. 44-8436 was used.
As seen in the newsletter, the leading edge of the paper is detected by a paper detection means that varies depending on the population of the transportation route, and a timer that sets the standard time to the exit is activated, and the machine reaches the exit within that time. There are devices that stop the fuser when the leading edge of the paper does not reach it.

However, if the paper has a file hole, when the paper moves over the paper detector and moves from a non-hole area to a hole area, or from a hole area to a non-hole area, the paper detector will detect the rear edge of each paper. Outputs false signals for passage and tip passage. Therefore, this erroneous signal may cause a malfunction in jam detection.

The present invention eliminates the above-mentioned drawbacks, and includes a jam ejecting device that ejects a jam using a moving member detection means and a timer, which is installed on a moving path of a moving member. The jam detection device is characterized in that it has a circuit for determining whether an edge has passed, and the determination circuit is arranged so as not to respond for a predetermined period of time even if the detection means performs a detection operation. 8. A block diagram showing a moving unit thereby; 1 is the first Oe* output means installed at the entrance of the moving path and spouts copying material (hereinafter referred to as a sheet);
The integral circuit that removes the edge signal from the ejection means, TI is the first tie that starts timed operation by the trailing edge signal of the sheet!
, Sf is a jetting means of ll52 installed near the exit of the moving system path and jetting out the sheet, T is a second timer which starts timed operation by the sheet tip signal from the above-mentioned ls2 jetting means &, and C is a first timer. The second ejection means 8. within a predetermined time by the timer T. A first discriminating means produces an output when the leading edge of the sheet is not ejected, and a second discriminating means produces an output when the ejecting hand R& of @2 does not detect the trailing edge of the sheet within a predetermined time determined by the timer T of @2. Discrimination means: G is a means for generating a jam signal based on the output of $1 or the second discrimination means, Y is a means for generating a sheet feeding drive source or a heater for fixing the sheet (fixed paper) in an appropriate position based on the jam signal. means, X
is a means for counting sheets or stopping the sheet for exposure preparation in response to a sheet leading edge signal from the first detecting means S1. - Here, the time required for the sheet to reach the @2p jetting means after jetting the rear end of the first timer sheet is set. Therefore, the time required for sugar production can be reduced.

Further, the lI20 timer is set to 0 for the time required for the sheet to pass through the second jetting means, so that it is possible to monitor the sheet in the metal path and determine whether or not feeding has been completed. As soon as the sheet is fed and passes through the ejection means S of IIEl, the 10th tie wTI is actuated, and when it reaches the second ejection means &, the timer T1 is released, so no jam signal is generated and the sheet reaches the second ejection means &. At the same time, the second timer operates and when the sheet normally passes through the second detection means &, the timer T! is released, so no jam signal is generated. If a jam occurs, a jam signal is issued by one of the timer outputs, and the sheet feeding means is stopped and the feeding of subsequent sheets is stopped to prevent damage to overlapping documents, or an alarm rung is activated. to ensure the safety of the equipment. In Patent Application Publication No. 49-1234, the leading edge of the sheet original fed to the exposure unit is detected, the -H sheet is stopped, and when the drum reaches a predetermined position, feeding is started again, and the sheet is exposed. This is particularly effective in electrophotographic copying equipment that is processed and then discharged.

Incidentally, the timer can also be set using a copying drum or the like and the time after the ejection of the bale end based on its rotation length.

Further, the present invention will be explained below by taking as an example a copying machine that continuously copies a large number of stacked sheet originals by continuous autofeeding, as shown in FIG.

The purpose of this copier company is to provide a copying machine that can perform copying with the highest efficiency from the standpoint of copying sheet originals. Conventionally, copying machines can be roughly divided into two types: sheet manuscript copying machines and copying machines capable of copying three-dimensional objects such as books.

Copying machines for sheet originals, which have an exposure section for transporting sheet originals, cannot copy thick documents such as books, but for sheet originals, the machine simply feeds the original into the insertion slot of the exposure section that exposes the sheet original. You can get a copy at.

In addition, compared to copiers for thick originals that have an original stand for placing thick originals, it is possible to increase the rounding and copying speed for the same process configuration without the rounding and backward movement of the original stand or optical system. .

However, there is a limit to the speed at which the user can feed each document into the insertion slot, so as machine performance improves, it becomes impossible to keep up with the speed that machines are capable of.
It was not possible to effectively utilize the speed that the copying material itself originally had. Furthermore, when copying an original consisting of several pages, it is necessary to load the exposed original first and reverse the order of the nine pages, resulting in a corresponding loss of time. friend.

The present invention improves the above points, and automatically and reliably continuously feeds sheet originals one by one to the conveying exposure section, and also makes a U-turn for sheet originals that have been side-lit. It is possible to load each or both of the discharging unit and the discharging unit in the order of the first loaded pages, so that even if they are loaded individually, they can perform their respective functions.

Therefore, it is possible to quickly insert a sheet original, and at the same time, the page order of the original is automatically arranged. This embodiment is a sheet document/book document copying machine in which a sheet document feeding section is combined with a document separating and feeding section and a discharge section.

The operation will be explained with reference to FIG.

With the side to be copied of the multiple sheet originals facing downward, place pages l [K from the bottom, with the last page on top, facing the stacking table 23. The top of the nine sheets of originals stacked on the roller roller 6, that is, the end of the original, is separated and conveyed, continuously passing through the drawer roller 8 and onto the original platen 91.
The leading edge of the sheet document is sent between conveyance rollers 90 built in the document sheet, and is ejected by the lamp 21 and light receiving element 22, and is temporarily stopped. The photosensitive drum 24 is at the specified position! When the sheet original rotates to t, the sheet document is again synchronized with the drum 24 by the conveying rollers 9 and 10, and the guide glass 16. The slit-exposed sheet original is conveyed between the guide plates] 7, passes through ejection rollers 11 and 12, and is ejected to an original tray 92 while making a U-turn. The conveyance speed of the pull-out roller 8 is higher than that of the feed roller 6, and the separation/feed roller continuously and reliably separates and feeds the first sheet document 1.
Create a gap between the trailing edge of ' and the leading edge of the second document. The second document is distinguished from the first document by this gap, and is similarly stopped and controlled in conjunction with the photosensitive drum 24. When the sheet original passes over the glass plate 16 of the illumination s25, it is illuminated by the lamp 26, and the image of the original is reflected by the reflection mirror 27.
An image is formed on the photosensitive drum 24 by the mirror lens 28 at the exposure section 29 . The photosensitive drum 24 rotates in the direction of the arrow, and is first charged to (+) by a primary charger 31 to which a high voltage is supplied from a high-voltage power source 30.Then, the original is exposed to slit light in the exposure section 29. At the same time, the static eliminator 32 to which AC high voltage is supplied from the power source 30 receives the AC static neutralizing action. Form.

After the liquid is developed by the developer 35 in the current stage 634, it is corona charged by the (-) high voltage applied to the post charger 36, and excess developer is removed without disturbing the developer. Squeezed out. The transfer paper P fed from the paper feed section by the crawler 3 or the like is separated by the separation belt 39 and guided to the drying and fixing section 40. The transfer paper P is heated and fixed in the fixing section 40, and then transferred to the static eliminator 47.
After removing the electric charge remaining on the surface, the paper is sent out from the discharge port onto a tray 49 by a discharge roller 48. The ejected transfer paper P is stacked with the copy side facing up and the last page number of the original facing down. When all of the originals stacked in this way have been copied, both sheet originals and transfer papers are loaded onto the first stacking stand 23. Splash.

In the copying machine described above, if a jam occurs near the roller 10 at the end of the miscellaneous light area and the rollers 11 and 12 of the guide plate 14 that reverses the sheet, and there is a delay in discharging the sheet to the tray 92, the subsequent sheet will jam. will be enlarged and important documents will be damaged.

In this example, the light source 21 and the light receiving element 22, which normally detect the leading edge of the sheet and temporarily stop it, are used as the first jetting means for ejecting a jam so that the jam does not spread. 0 which ejects and activates the first timer shown in FIG. 3, and a light source 120 provided near the discharge port. (by the second jetting means of the light-receiving element 121), it is determined whether or not the sheet has caused a delayed jam. Further, the second ejecting means ejects the tip of the 7-toe to release the timer IIgl, and at the same time activates the second timer, and the second ejecting means ejects the rear end of the plate and receives light depending on whether it is a friend or not. To blow out jam remaining on the element 121.

Also, it can be seen that the tub has a portion where the light transmittance in the hole for the file differs greatly. For example, when a file sheet with holes is fed in from the large format side, the detection signal when moving from the sheet section to the hole is used as the sheet trailing edge signal, and the OWI output signal when moving from the hole to the sheet section is used as the sheet leading edge signal. The light receiving element 22 outputs as . The timer is activated by this erroneous signal, causing a jam to erupt and malfunction.

In this example, this erroneous signal is removed by an integrating circuit, and only the signal of the actual leading edge or trailing edge of the sheet is used as the input signal.

An example of the jam ejection circuit for the above will be described in detail with reference to FIG. 3. In the connection relationship, the DC power supply of this circuit is connected to connector J2-10. +24V is connected to the voltage source obtained from the power supply in the copying machine via J2-1, and ground Ov is connected to B.

Figure 2 light +121. The sheet ejection signal C from the light receiving element 22 is input as ±24V from another circuit (not shown) to this circuit via the connector Jr-2. Input connector J
1-2 is the emitter of transistor Q1, resistors R,,R
. Construct an integrator circuit. Transistor Q1
The collector of is connected to the cathode of resistor R1 and diode D through the capacitor fC, forming a differentiating circuit, and the anode of diode D is connected to the cathode of transistor Q, which forms the monostable multivitalator for the @1 timer. collector,
and the base of the transistor Q via the capacitor C1. The base of transistor QI is reverse biased by resistor R, so that normally transistor q is on and therefore transistor Q4 is off. The timer time is resistor I
It is set by IL, and condant Cv. The diode D4 is for maintaining the film of the transistor Q4. The collector of transistor Q is connected to the base of transistor Q of the inverter via a resistor R1f, and the collector of transistor Q
The collector of is connected to the resistor Lu, Rty, diode D, ) transistor Q, through the consonator C of the differential circuit.
connected to the collector of The resistor L is connected to the gate of the thyristor Q through the diode D, and the anode of the thyristor Q is connected to the jam ejection light emitting diode DJ@
connected to.

To explain the operation, when the sheet is inserted now, the capacitor Cs is charged via the resistor & by the ejection signal, and when the charging potential causes the Situena diode ZDI to reach the break voltage, the transistor Q becomes conductive. and transistor Q1
conducts and produces an output of 24V with respect to the capacitor fC. But shi. The 24V rising signal corresponding to the tip of the gate is placed in place by diode D8 and therefore does not activate the monostable multi. Therefore, while the sheet is temporarily stopped and the light receiving element 22 is ejecting the sheet, the first timer does not start operating. The drum 24 of the copying machine rotates to a predetermined position, the sheet starts to be conveyed again, and when the trailing edge of the sheet passes the light receiving element 22, the input signal changes to 0. Therefore, at that moment
A trigger pulse of electricity is generated by C4 and diode D. The monostable multi is activated by this pulse.The collector potential of the transistor Qa and the transistor Q,
The base potential of Q4 decreases, turning off transistor Q4.

Therefore, since the collector potential increases, transistors Q and Q1 are turned on. This on state continues until capacitor Cv is charged and transistor Q4 is turned on. Thereafter, when the transistor Q6 is turned on, the transistor Q changes from on to off, and a positive trigger pulse that activates the thyristor Q is generated by the capacitor Ca. That is, the jam ejection signal is issued after the time required for the leading edge to reach the second light receiving element 121 after the light receiving element 22 detects the trailing edge of the sheet.

Here, if there is a file hole in the sheet, the hole causes the light receiving element 22 to generate a pulse similar to that when the trailing edge of the sheet is detected.

However, due to the file hole near the tip of the sheet, the sheet detection signal does not have enough width to charge the capacitor fC to the break potential of the Zener diode ZDI, so the transistors Q, , Q, cannot be activated. Therefore, the monostable multi is not driven by an erroneous signal caused by the hole.

Next, to explain the part for determining whether or not a delay jam has occurred, in the S configuration, the light receiving element 121H resistor KR-, , l
llm11 resistor VRIwosukeLte+24VK, resistor,
A resistor R41 is connected to the input terminal 3 of the operational amplifier Q11 through
is connected to the input terminal 2 through the resistor R4I, and to ground through the resistor R4I. The operational amplifier Qll outputs a low level (approximately +2V) output from the terminal 6 when the light receiving element 121 receives the light from the light source 120, and outputs a high level (+2V) output when the light is interrupted.
2' 4 V). Output terminal 6 is a resistor,
It is connected to the base of transistor QtI via a resistor R4$, and to the base of transistor QtI via a resistor R4$. The collector of the transistor Q is connected to the differential capacitor C.

That is, when the sheet is detected by the light receiving element 121, a bulk level is output from the output terminal 6 of the operational amplifier Q++, so that the transistor Q is turned on. Therefore, when the sheet is normally conveyed and reaches the light receiving element 121, the jam ejection pulse from the monostable multi-layer is grounded by the transistor Q, and the thyristors are not activated, so that no jam is displayed. However, if there is a delay during the sorting movement or a paper jam occurs, the transistor Q remains off, so the thyristor Q is activated by the pulse from the monostable multi, and the light emitting devices 1t--d, .
lights up to indicate a jam.

Next, to explain the parts of the safety circuit that operate together with this jam display, the anode of the light emitting diode Dta is connected to the base of the transistor Q via the Zener diode ZD and the resistor Rf4, and the collector of the transistor Q@ It is connected to the base of transistor q via resistor fLI4.

Further, the collector of transistor Q is connected to transistor Q1.
connected to the emitter of 8L is a plunger for rotating the rollers 6.7 and 8.9 of the sheet original feeding section, and SL is a plunger for rotating the rollers 9 and 9' of the main body. A microswitch is turned on when the sheet document feeding section is attached to the document table 91, and connectors J and - are connected to a granger (not shown) for stopping the rollers 9 and 9'.

That is, when thyristor Q is inactive, transistor Q,
, Q operate, so plunger SL, .

SL can be operated in response to a signal from the connector JIS that is synchronized with the paper feeding of the copying machine main body, and automatically feeds stacked original sheets. However, when thyristor q operates and generates a jam signal, transistors Q, , Q, turn off and plunger SL,.

The signal driving SL disappears. At the same time, the transistor Q1 is turned on, so that the stop plunger is actuated to stop the timing rollers 6.7 and 8.9 and interrupt automatic sheet feeding. Therefore, when a jam occurs, conveyance of subsequent sheets is stopped to prevent the jam from expanding.

Next, to explain the detection when a sheet jams and stays on the light receiving element 121, the collector of the transistor Q+a is a resistor It. , is connected to the anode of the switching element Q+v via the diode DI, and is connected to the capacitor C1.
Connected to M. The gate of switch element Q□ is resistor Ra
A program voltage divided by g and fLaa is applied, and the cathode of the switching element Qtv is connected to the gate fc of the thyristor Q.

When the leading edge of the beaten sheet reaches the light receiving element 121, the output of the operational amplifier Qra turns on the transistor Qll and turns off the transistor Q1. And the capacitor tC■ is the resistance R
The photovoltaic signal is started at a predetermined time constant via the number . When the charging potential reaches the gate potential of the switching element Q, the switching element Q+v is turned on. Here, the adjustment resistor VR is charged for a period longer than the time required for the sheet to pass over the light receiving element 121. Therefore, after the leading edge of the sheet is detected, the sheet normally passes through the light receiving element 121, and when the trailing edge of the sheet is detected, the output of the operational amplifier Qll decreases and the transistor Q,- turns on. Therefore, the electric field of the capacitor tC■ is discharged through the diode DI and does not turn on the switching element Qlf, which would turn on the thyristor q. No jam signal occurs. However, when the sheet stops there regardless of whether it reaches the light receiving element 121, the thyristor QJf ) ! is turned on by the switching element Q+v. j is detected, the light emitting diodes D, . . . indicate a jam, and the roller drive is stopped as described above, and automatic paper feeding is interrupted.

Note that the transistors of the resistor R+w and the capacitor C- connected to the capacitor C1 via the diode D. when the power supply of 24 V is turned on are also off, so that the capacitor C1 absorbs the transiently generated positive pulse. Therefore, thyristor q will not operate due to a malfunction when the power is turned on. Further, the counter CNT counts the #i sheet, and the above-mentioned integrating circuit produces an erroneous count. capacitor c,,c
The 4 resistors further smooth the 24V power supply.

Another example of the present invention will be explained with reference to Figure @4.
In the figure, an inverter circuit consisting of a transistor Qt is connected to the collector of the transistor Q in the integrating circuit, and the input signal C has a zero potential when a sheet is detected, and a voltage of +24 V when no ejection occurs. With this configuration, a short width pulse input signal due to the hole in the sheet is absorbed by the controller C1, so it is not output from the transistor Q1.Therefore, regardless of the hole, the transistor Q remains off while the sheet is present, so the transistor Q The collector potential of (2) remains at 24V.

When the rear edge of the sheet is detected, the transistor Q!・
The collector potential of D drops from 24V to 0, and the diode D outputs a negative pulse to activate the monostable multi. At this time, the charging time of the capacitor C4 is set to be equal to or less than the interval between sheets in continuous autofeed.

As described above, the present invention detects the rear end of the movable member and determines whether the movement of the movable member is completed within a predetermined time after the end of the chain is released, and then ejects the jam, so the predetermined time setting may be short. It is possible to eject a jam for each moving member in response to continuous autofeed that is fed before the moving member is discharged out of the moving path.

[Brief explanation of the drawing]

FIG. 1 is an example of a block diagram of a jam ejection pocket according to the present invention.
FIG. 2 is a sectional view of a copying machine with an auto feeder using the present invention, FIG. 3 is an example of a jam detection circuit according to the present invention, and FIG. 4 is another example of a jam ejection circuit according to the present invention.
In the figure, Sl: first detection means for detecting the trailing edge of the sheet, T1: first timer means, and DI=llK1 determination means.

Claims (1)

[Claims] Shin-Yu - # Oml Set up on the plow road is tied with nine moving parts, Chite Soft! According to a jam detection device that detects a jam using
The moving part has a circuit for determining whether the leading end or the rear end of the moving member passes over the detecting means, and the determining circuit is configured to not respond for a predetermined period of time even if the detecting means performs a detection operation. Jam detection device O featuring Ehito