JP2003034059A - Web conveying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a web conveying device capable of readily and surely judging whether or not a plurality of webs can be conveyed. SOLUTION: This web conveying device is equipped with a conveyance driving means for driving a web conveying mechanism in a predetermined timing and a tip detecting sensor for detecting a tip of the web to be conveyed by the web conveying mechanism driven by the conveyance driving means is disposed on a web conveying path. The web conveying device has a judging means for judging go or no-go of the conveying of the web based on the detected output of the tip detecting sensor. The web conveying device comprises a conveyance preparing means that positions the tip of the web to an initial position by driving the web conveying mechanism in the reverse rotational direction by means of the conveyance driving means when the sensor in the web conveyance path detects the tip of the web before the conveyance operation along with an image forming operation is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a web transport device for sequentially transporting webs wound in a roll shape such as continuous paper.

[0002]

2. Description of the Related Art Some printers and cutters for printing and cutting webs are provided with a web transporting device for transporting webs such as continuous paper and film in functional units such as a printing unit and a cutting unit. Such a web transfer device forms a web holding member for holding a web wound in a roll shape in a freely feedable manner by a spool shaft or a hopper, and sequentially conveys the webs set on such a web holding member. A web feed mechanism is formed by feed rollers and endless belts, in which web transport paths are formed by web guides such as supporting plates facing each other, and webs are sequentially fed to the web transport paths formed by the web guides. Has become.

Further, in such a web transfer device,
A remaining amount detection sensor for detecting the remaining amount of the web set on the web holding member and an end detection sensor for detecting the end of the web set on the web holding member are, for example, reflections arranged around the web holding member. It is formed of a photosensor, a transmissive photosensor, a pressure sensitive switch, and the like. Therefore,
In such a web transport device, when each of the remaining amount detection sensor and the end detection sensor individually detects the remaining amount and the end of the web, etc., the CPU (Central P
A data processing means such as a processing unit) notifies the user of the end of the web or the end of the web by a display on the display or a voice of a speaker.

In an electrophotographic apparatus equipped with such a web transfer device, the main body power supply for supplying power to the charging charger, fixing heater, etc. also supplies power to the web feeding mechanism of the web transfer device. It has a structure that Therefore, in such an electrophotographic apparatus, when the web transport device sequentially feeds the web from the web holding member to the web transport path by the power supply of the main body power supply, the charging charger that operates by the power supply of the main body power supply is used. The toner is transferred to the web by a photosensitive drum or the like, and an image is printed.

In such an electrophotographic apparatus, for example, when the end detection sensor of the web transfer device detects the end of the web, the power supply of the main body power supply is immediately interrupted to stop the operation of each part at the same time. It is designed to prevent web jams. In other words, in such an electrophotographic apparatus, power is supplied from the main body power source to each unit only when the remaining amount detection sensor and the end detection sensor of the web transport device detect the presence of the web, and the above-described printing operation is performed. Ready to run.

[0006]

In the web transporting apparatus as described above, the web feeding mechanism can sequentially feed the web from the web holding member to the web transporting path.
This web can be used as a recording medium of an electrophotographic apparatus.

Here, in such a web transfer device,
In order for the web feeding mechanism to freely feed the web, the tip of the web set on the web holding member needs to be inserted into the web transport path. In other words, the web set on the web holding member cannot be fed without the tip being inserted into the web transport path, but even in such a case, the remaining amount detection sensor and the end detection sensor of the web holding member are present. The web feed mechanism can be activated to detect the.

When the web feeding mechanism operates in such a state, the web held by the web holding member is not well fed to the web conveying path, so that a jam occurs. It should be noted that such a phenomenon frequently occurs in a large-sized web transporting device having a plurality of web holding members when a user sets a spare web on a web holding member that is not to be used for storage. .

Further, even when the web is set to be fed to such a web transporting device, when the web transporting device is stopped for a long period of time, the tip of the web falls off from the web transporting path due to bending and the like. It may be impossible to send.
In such a case, since the user cannot recognize that the web set to be able to be fed to the web transport device has become unfeedable, a jam is generated by performing the operation of feeding the web. .

Further, in an electrophotographic apparatus equipped with such a web transporting device, when the above-described web feed failure or jamming or other malfunction occurs, the main body power source is used to prevent the progress of such malfunctions. The power supply to the plant is also interrupted. However, in such an electrophotographic apparatus, since it takes time for the fixing heater to reach the specified temperature from the start-up, if the power supply is interrupted as described above, the printing operation is not restarted even if the power supply is restarted. It is not preferable because the restart will be delayed.

[0011]

The invention according to claim 1 is
A web feeding mechanism that includes a web holding member that holds the web so that the web can be fed, forms a web conveyance path through which the web set in the web holding member is conveyed, and feeds the web to the web conveyance path. In the web transporting device provided with, a feeding driving means for driving the web feeding mechanism at a predetermined timing is provided, and the leading end of the web fed by the web feeding mechanism driven by the feeding driving means is detected. A leading edge detection sensor is arranged in the web transport path, and a possibility determination means for determining whether or not the web can be fed based on the detection output of the leading edge detection sensor disposed in the web transport path is provided, and an image forming operation is involved. Before the feeding operation, when the sensor of the web transport path detects the leading end of the web, the feeding drive means drives the web feeding mechanism in the reverse rotation to move the tip of the web. The provided feed preparation unit arranged in the initial position.

According to a second aspect of the present invention, in the web transporting apparatus according to the first aspect, the plurality of web holding members and the plurality of webs are provided, and the leading edge detection sensor is one of the plurality of webs fed in common. One is provided in the web transport path.

According to a third aspect of the present invention, in the first aspect of the present invention, a main body power source for supplying electric power to each part such as the web feeding mechanism is provided, and the activation timing of the main body power source drives the web feeding mechanism. The timing was set in the feeding drive means.

According to a fourth aspect of the present invention, in the first aspect of the present invention, a set detection sensor for detecting the setting of the web on the web holding member is provided, and the detection timing of the set detection sensor drives the web feeding mechanism. The timing was set in the feeding drive means.

According to a fifth aspect of the invention, in the invention of the fourth aspect, the set detection sensor is formed by a remaining amount detection sensor for detecting the remaining amount of the web set on the web holding member.

According to a sixth aspect of the present invention, in the fourth aspect of the invention, the set detection sensor is formed by an end detection sensor that detects the end of the web set on the web holding member.

According to a seventh aspect of the present invention, in the first aspect of the present invention, a single web transport path is commonly formed by a web guide to which a plurality of webs individually set on a plurality of web holding members are commonly fed. A plurality of web feeding mechanisms for individually feeding the plurality of webs are provided in the web transport path, and feeding drive means for selectively driving one of the web feeding mechanisms is provided. Forming one tip detection sensor for detecting the tip of the web fed by the web feeding mechanism driven by the driving means in the web transport path,
When the leading edge detection sensor of the web transport path detects the leading edge of the web, the feeding drive means drives the web feeding mechanism in the opposite direction to arrange the leading edge of the web at an initial position. A determination storage unit is provided for storing the feedability determined by the availability determination unit for the web arranged by the feed preparation unit.

[0018]

According to the first aspect of the present invention, when the leading edge detection sensor detects the leading edge of the web fed to the web transport path in the web feeding mechanism driven by the feeding driving means at a predetermined timing,
The availability determination means determines whether or not the web can be fed based on this detection output, whereby the availability of feeding the web set on the web holding member can be easily and reliably detected.
In particular, when one leading edge detection sensor for one web transport path to which a plurality of webs are commonly fed detects the leading edge of the web, the feeding preparation means drives the web feeding mechanism in the reverse direction by the feeding driving means. By arranging the leading end of the web at the initial position, it is possible to determine whether or not each of the plurality of webs commonly conveyed by one web transport path can be fed by one leading end detection sensor.

According to the second aspect of the present invention, the structure can be simplified because only one front end detection sensor is provided in one web transport path through which a plurality of webs are commonly fed. .

According to the third aspect of the present invention, the feeding drive means drives the web feeding mechanism at the activation timing of the main body power source for supplying electric power to each part such as the web feeding mechanism.
Even if the web set to be freely fed becomes unfeedable during the rest period of the main body power supply, the undeliverable web can be detected easily and reliably.

According to the fourth aspect of the present invention, when the set detection sensor detects the setting of the web on the web holding member, the feeding drive means drives the web feeding mechanism at this timing, so that the web can be fed. Can be detected immediately after the set.

According to the fifth aspect of the present invention, the set detection sensor is formed by the remaining amount detection sensor for detecting the remaining amount of the web set on the web holding member, so that the set detection sensor is realized by utilizing the existing member. can do.

According to a sixth aspect of the present invention, the set detection sensor is formed by the end detection sensor for detecting the end of the web set on the web holding member, and the set detection sensor is realized by utilizing the existing member. You can

According to a seventh aspect of the present invention, when one leading edge detection sensor of one web transport path through which a plurality of webs are commonly fed detects the leading edge of the web, the feeding preparation means is the feeding drive means. The web feeding mechanism is driven in the reverse direction to position the leading end of the web at the initial position, and the determination storage means stores the feeding possibility of the arranged web, so that the web is commonly conveyed by one web conveying path. It is possible to determine whether or not each of the plurality of webs is fed by a single leading edge detection sensor and store the determination result in the determination storage means.

[0025]

An embodiment of the present invention will be described below with reference to the drawings. First, the paper feeding unit 1 which is the web transporting device of the present embodiment is formed, for example, as a part of a laser printer 2 which is an electrophotographic device, and slides individually with respect to the device body 3 of the laser printer 2. It is formed as a free first / second paper feed cassette 4, 5.

In the paper feeding unit 1, the photosensitive drum, the transfer charger, and the fixing heater (none of them are shown).
The paper transport path 6 of the main body 3 of the apparatus, the paper transport path 7, which is the web transport path of the first paper feed cassette 4,
8 communicate with each other, and the second paper feed cassette 5 is connected to the paper feed paths 7 and 8 of the first paper feed cassette 4.
The paper transporting path 8 which is a web transporting path is connected. Here, in this paper feeding unit 1, four spool shafts 13 to 16 which are web holding members which individually hold four continuous papers 9 to 12 which are webs wound in a roll shape so as to be freely fed. 2 are provided in each of the first and second paper feed cassettes 4 and 5, and the continuous papers 9 to 12 held by the spool shafts 13 to 16 are sequentially conveyed. The paper transport paths 7 and 8 are formed by web guides 17 and 18 having a predetermined shape.

In the paper feeding unit 1, four sets of feed rollers 19 for sequentially feeding the four continuous papers 9 to 12 in common to the paper transport path 7 in which the paper transport path 8 communicates integrally. 22 to 23 are sheet feeding positions 23 to 2 of the sheet conveying paths 7 and 8 respectively facing the spool shafts 13 to 16.
6, the continuous paper 9 is provided at each of the positions of the paper transport path 7 that communicate with the paper transport paths 6 and 8.
Relay rollers 27 and 28 are provided to assist the conveyance of the sheets 1 to 12. Also, the first and second paper feed cassettes 4, 5
At the predetermined position of the paper transport paths 7 and 8, the continuous paper 9
Manual cutters 29 and 30 for manually cutting the sheets 12 to 12 are provided one by one, and the continuous papers 9 to 12 are automatically placed at predetermined positions in the sheet conveying path 7 of the first sheet feeding cassette 4. An auto cutter 31 for cutting is provided.

In the paper feeding unit 1, four sets of the feed rollers 19-2 are set at a predetermined timing described later.
A feed drive unit for selectively driving one of the two is formed by a drive motor, a drive control circuit (neither shown), and the feed roller 1 driven by the feed drive unit.
The leading edge detection sensor 32 for detecting the leading edges of the four continuous papers 9 to 12 conveyed by 9 to 22 is located between the manual cutter 29 and the automatic cutter 31 of the first paper feed cassette 4. It is formed by a single reflection type optical sensor arranged in the sheet conveying path 7.

Further, in the paper feeding unit 1, a propriety determining means for determining whether or not the continuous papers 9 to 12 can be fed based on the detection output of the leading edge detection sensor 32 arranged in the paper transport path 7, A data supply circuit (not shown) such as a CPU forms a feed control unit that controls whether or not the feed rollers 19 to 22 are driven by the feed drive unit based on the determination result of the availability determination unit. .

Further, in the paper feeding unit 1, when one of the four continuous papers 9 to 12 is selectively conveyed by the feed rollers 19 to 22 driven by the feeding drive means at a predetermined timing described later. , The continuous paper 9 being conveyed
When the leading edge detection sensor 32 detects the leading edge of the sheet 12, the feed driving means rotates the feed rollers 19 to 22 in the opposite direction to arrange the leading edge of the continuous paper 9 to 12 at the initial position. , A determination storage means that is formed of a data processing circuit such as a CPU and that stores the feedability determined by the availability determination means such as the CPU for the continuous papers 9 to 12 arranged by the feeding preparation means. , RAM (Rando
m Access Memory) or the like.

Here, in the paper feeding unit 1, a main body power source (not shown) for supplying electric power to the charging charger, the fixing heater and the like of the laser printer 2 is fed by the feeding driving means of the paper feeding unit 1 and the above-mentioned. Electric power is also supplied to the auto cutter 31 and the like, and the start timing of the main body power source is set in the feeding drive means as the first drive timing of the feed rollers 19 to 22 as described above.

Further, in the paper feeding unit 1, the continuous papers 9 to 12 set on the spool shafts 13 to 16 are used.
The remaining amount detection sensors 33 to 36 for detecting the remaining amount of the spool shafts 13 to 16 are formed by reflection type optical sensors individually arranged above and behind the spool shafts 13 to 16, respectively.
The end detection sensors 37 to 40 that detect the end of the continuous papers 9 to 12 set to
16 to 16 are individually formed on the reflective optical sensors.

In this paper feeding unit 1, the set detection sensors for detecting the setting of the continuous papers 9-12 on the spool shafts 13-16 are the remaining amount detection sensors 33-36 and the end detection sensor 37-. 40, and the timing at which these remaining amount / end detection sensors 33 to 40 detect the continuous papers 9 to 12 is fed as the second drive timing of the feed rollers 19 to 22 as described above. It is set in the drive means.

The laser printer 2 having the paper feeding unit 1 as a part thereof has a message output means such as a display for displaying various message data and a speaker for outputting voice (both not shown). Three
The message data to be notified and output by the message output means such as the display is provided in the ROM (Re
It is set in advance in a message storage means such as ad only memory). For example, message data individually indicating whether or not each of the four continuous papers 9 to 12 can be fed is also set in this message storage means, and this message data corresponds to the determination result of the availability determination means. The availability notification means for selectively outputting the notification by the message output means such as the display is formed by a data processing circuit such as a CPU.

In such a configuration, in the laser printer 2 equipped with the paper feeding unit 1, the main body power source for supplying power to the charging charger, the fixing heater, etc., also supplies power to the paper feeding unit 1. Therefore, in this paper feeding unit 1, one set of feed rollers 19 to 22 is selectively driven to rotate by the power supplied from the main body power supply.
Is configured to sequentially feed one of the four continuous papers 9 to 12 from the paper transport paths 7 and 8 to the paper transport path 6 of the apparatus main body 3.

In the laser printer 2, the paper feed unit 1 detects the remaining amount and the end of the continuous paper 9-12 individually by the remaining amount detection sensors 33 to 36 and the end detection sensors 37 to 40, respectively. Message indicating that the continuous paper 9-12 has not been set, that the continuous paper 9-12 is about to end, that the continuous paper 9-12 has ended, etc. The output means informs and outputs to the user.

Here, in the laser printer 2, for example, one continuous paper 9 whose end is notified as described above.
When replenishing the paper feeding unit 1, the first paper feeding cassette 4 of the paper feeding unit 1 is first pulled out from the apparatus main body 3 and the continuous paper 9 is set on the spool shaft 13. The leading end is manually inserted into the sheet conveying path 7 by the feed roller 19. Next, the front end of the continuous paper 9 inserted into the paper transport path 7 is cut with a manual cutter 29 to adjust the shape, and the cut pieces are removed, and then the first paper feed cassette 4 is loaded into the apparatus main body 3. Will be done. At this time, in the laser printer 2, when the paper feeding unit 1 is pulled out from the apparatus main body 3 as described above, the power supply from the main body power source to each unit is interrupted. Is loaded into the apparatus main body 3 and then restarted.

In the paper feeding unit 1, when the continuous paper 9 is replenished and the power supply is restarted as described above, the remaining amount / end detection sensor 3 which operates with the supplied power is supplied.
3, 37 detects the newly replenished continuous paper 9, and the feeding drive means selectively drives one feed roller 19 in accordance with this detection timing, so that only the newly replenished continuous paper 9 is produced. The sheets are sequentially fed to the sheet conveyance path 7. Therefore, when the leading edge detection sensor 32 detects the leading edge of the continuous sheet 9 fed through the sheet conveying path 7, the availability determination means determines whether the continuous sheet 9 can be fed according to the detection output. Whether the paper 9 can be fed is stored in a judgment storage means such as a RAM.

In the paper feeding unit 1, the four paper sheets 9 to 12 are commonly conveyed in the paper conveyance path 7 in which the front end detection sensor 32 detects the front end of the continuous paper 9 as described above. Since the leading edge detection sensor 32 has detected the leading edge of the continuous paper 9, the feeding preparation means causes the feeding drive means to rotate the feed roller 19 in the opposite direction by a fixed amount, and the other continuous paper 9 is continuously fed. It is placed at an initial position where it can be fed without interfering with the papers 10 to 12. By doing so, in this paper feeding unit 1, one paper transport path 7
Can feed four continuous papers 9-12 freely
Since the leading edge of each of the continuous papers 9 to 12 can be detected by the single leading edge detection sensor 32, the number of the members is small, which can contribute to the reduction in size and weight of the laser printer 2 and the improvement in productivity. Moreover, as described above, the tip detection sensor 32
Even if the continuous paper 9 detected in step 1 is retracted to the initial position where it does not interfere with the other continuous papers 10 to 12, the fact that the continuous paper 9 can be fed is stored in the judgment storage means such as the RAM. The continuous paper 9 can always be freely fed.

Further, in the paper feeding unit 1, when the continuous paper 9 is prepared to be freely fed as described above, based on the stored information of the judgment storage means such as the RAM showing the freely feeding.
Since the feed roller 19 is set so as to be freely driven by the feeding drive means, the user can freely feed the continuous paper 9 and use it for image printing of the laser printer 2 as desired. Further, in the paper feeding unit 1, message data indicating that the continuous paper 9 can be fed is sent from the message storage means such as the ROM based on the storage information of the determination storage means such as a RAM that indicates that the continuous paper 9 can be fed. Since it is read out and displayed and output on the display, the user can easily recognize that the continuous paper 9 can be fed by visually recognizing the display output.

In the paper feeding unit 1, the leading edge detecting sensor 32 detects that the leading edges of the continuous papers 9 to 12 set on the spool shafts 13 to 16 are inserted into the sheet conveying paths 7 and 8. Feed roller 19 only if
Since it is possible to freely feed the sheet by means of .about.22, the tip of the spool shaft 1 is not inserted into the sheet conveying paths 7 and 8 unlike the conventional case.
The operation failure that the feed rollers 19-22 are driven in the state of the continuous papers 9-12 set in 3-16 does not occur.

Further, in the paper feeding unit 1, when the continuous papers 9 to 12 are set on the spool shafts 13 to 16 as described above or when the power source of the main body is activated, the continuous papers 9 to 12 are automatically fed. Since it is determined whether or not the sheet can be sent, for example, the user may use a spare continuous paper (not shown) on the spool shafts 13 to 16.
Spool shaft 13 to 1 when set for storage
Even if the continuous papers 9 to 12 set to be freely fed to the sheet 6 drop out of the paper transport paths 7 and 8 due to a long-term suspension and cannot be fed, the continuous papers 9 to 12 are fed. The malfunction of driving the impossible feed rollers 19 to 22 does not occur.

In other words, in the paper feeding unit 1, whether or not the continuous papers 9 to 12 can be fed is reliably detected, and malfunctions such as jams and idling of the feed rollers 19 to 22 are prevented. The power supply of the main body of the laser printer 2 is prevented from being stopped by the above, and the printing operation is not delayed.

Moreover, in the paper feeding unit 1, when it is detected that the continuous papers 9 to 12 have been set on the spool shafts 13 to 16 as described above, a series of judgments as to whether or not the continuous papers 9 to 12 can be fed. It is supposed to start the operation of
Since the set detection sensor that detects the setting of the continuous papers 9 to 12 is formed of the existing remaining amount detection sensors 33 to 36 and the end detection sensors 37 to 40, the increase in the number of members is reduced and the laser printer 2 is provided. It contributes to smaller size and lighter weight and improved productivity.

[0045]

According to the first aspect of the present invention, a web holding member for holding the web in a freely feedable manner is provided, and a web carrying path for carrying the web set on the web holding member is formed. In a web transporting device having a web feeding mechanism for feeding the web on a transporting path, a feeding driving means for driving the web feeding mechanism at a predetermined timing is provided, and the web feeding driven by the feeding driving means. A leading edge detection sensor that detects the leading edge of the web fed by the feeding mechanism is disposed in the web transport path, and whether or not the web can be fed is determined by the detection output of the leading edge detection sensor disposed in the web transport path. When the sensor of the web transport path detects the leading edge of the web before the feeding operation accompanied by the image forming operation, the possibility of determining is provided, and the feeding drive means feeds the web. By providing the feeding preparation means for driving the structure in the reverse rotation to dispose the tip of the web at the initial position, it is possible to easily and reliably detect whether or not the web set on the web holding member can be fed. Therefore, it is possible to prevent a malfunction such as driving the web feeding mechanism with respect to a web that cannot be fed, and in particular, one tip of one web conveyance path through which a plurality of webs are fed in common. When the detection sensor detects the leading edge of the web, the feeding preparation means drives the web feeding mechanism in the reverse direction by the feeding driving means to position the leading edge of the web at the initial position, thereby making it common to one web conveyance path. This has the effect that it is possible to determine whether or not each of the plurality of webs to be conveyed to each of the webs can be fed by a single tip detection sensor.

According to a second aspect of the present invention, in the web transporting apparatus according to the first aspect, there are a plurality of web holding members and a plurality of webs, and the leading edge detection sensor is one of the plurality of webs fed in common. Since one web transfer path is provided, the structure can be simplified.

According to a third aspect of the present invention, in the first aspect of the present invention, a main body power source for supplying electric power to each part such as the web feeding mechanism is provided, and the activation timing of the main body power source is used to drive the web feeding mechanism. By setting the feeding drive means as the timing, even if the web set to be freely fed becomes unfeedable during the rest period of the main body power supply, the unfeedability can be detected easily and reliably. Therefore, it is possible to prevent an operation failure such as driving the web feeding mechanism for a web that cannot be fed.

According to a fourth aspect of the present invention, in the first aspect of the present invention, a set detection sensor for detecting the setting of the web on the web holding member is provided, and the detection timing of the set detection sensor is used to drive the web feeding mechanism. By setting the feeding drive means as the timing, it is possible to detect whether or not the web can be fed immediately after setting, so that a malfunction such as driving the web feeding mechanism for a web that cannot be fed can be detected. It has effects such as prevention.

According to a fifth aspect of the present invention, in the invention according to the fourth aspect, the set detection sensor is formed by a remaining amount detection sensor that detects the remaining amount of the web set on the web holding member. Since the set detection sensor can be realized by diverting the above, there is an effect that the increase in the number of members can be reduced, the size and weight can be reduced, and the productivity can be improved.

According to a sixth aspect of the invention, in the invention according to the fourth aspect, the set detection sensor is formed by the end detection sensor that detects the end of the web set on the web holding member, so that the existing member is reused. Since the set detection sensor can be realized by the above, there is an effect that an increase in the number of members can be reduced, the size and weight can be reduced, and the productivity can be improved.

According to a seventh aspect of the present invention, in the first aspect of the present invention, a single web transfer path is formed by a web guide to which a plurality of webs individually set on a plurality of web holding members are commonly fed. A plurality of web feeding mechanisms for individually feeding the plurality of webs are provided in the web transport path, and feeding drive means for selectively driving one of the web feeding mechanisms is provided. One leading edge detection sensor for detecting the leading edge of the web conveyed by the web feeding mechanism driven by the driving means is formed in one of the web conveyance paths, and the leading edge detection sensor of the web conveyance path is the When the leading edge is detected, the feeding drive means drives the web feeding mechanism in the reverse direction to provide a feeding preparation means for arranging the leading edge of the web at an initial position, and the web arranged by the feeding preparation means. By determination means is provided determining storage means for storing a possible feed which is determined for,
Since it is possible to determine with a single tip detection sensor whether or not each of a plurality of webs that are commonly conveyed in one web conveyance path can be stored and stored in the determination storage means, a malfunction occurs with a simple structure. It is possible to freely feed a plurality of webs to one web transport path without having to do so.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view illustrating the internal structure of a paper feeding unit that is an embodiment of a web transporting device of the present invention.

[Explanation of symbols]

1 Web transport device 6-8 Web transport path 9-12 web 13-16 Web holding member 17,18 Web guide 19-22 Web feeding device 32 Tip detection sensor 33-36 Remaining amount detection sensor 33-40 set detection sensor 37-40 end detection sensor

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2C058 AB02 AB08 AC08 AE04 AE09                       AF06 HA10 HC02                 2C060 BA04 BC03 BC12 BC15 BC84                 3F052 AA01 AB05 BA02 BA14 CA02                       DA01                 3F064 AA02 BA05 EB01                 3F103 AA01 DA03 EA01

Claims (7)

[Claims] 1. A web holding member for holding a web so that the web can be fed freely is provided, a web carrying path for carrying the web set on the web holding member is formed, and the web is fed to the web carrying path. In a web transporting device provided with a web feeding mechanism, a feeding driving means for driving the web feeding mechanism at a predetermined timing is provided, and the web feeding mechanism driven by the feeding driving means feeds the web. A front end detection sensor for detecting the front end of the web is arranged in the web conveyance path, and a propriety determination means for determining whether or not the web can be fed by the detection output of the front end detection sensor arranged in the web conveyance path is provided. Before the feeding operation accompanied by the image forming operation, when the sensor of the web conveyance path detects the leading edge of the web, the feeding drive means drives the web feeding mechanism in the reverse rotation to move the web. A web transporting device comprising a feeding preparation means for arranging the tip of the web at an initial position. 2. A plurality of web holding members and a plurality of webs are provided, and one leading edge detection sensor is provided in one web transport path through which the plurality of webs are commonly fed. The web transfer device according to 1. 3. A main body power source for supplying electric power to each part of the web feeding mechanism and the like, and a start timing of the main body power source is set in the feeding drive means as a drive timing of the web feeding mechanism. The web transfer device according to claim 1. 4. A set detection sensor for detecting the setting of the web on the web holding member is provided, and the detection timing of the set detection sensor is set in the feeding drive means as the drive timing of the web feeding mechanism. The web transfer device according to claim 1. 5. The web transfer apparatus according to claim 4, wherein the set detection sensor is formed by a remaining amount detection sensor that detects the remaining amount of the web set on the web holding member. 6. The web transfer apparatus according to claim 4, wherein the set detection sensor is formed by an end detection sensor that detects the end of the web set on the web holding member. 7. A web guide is used to form one web transport path through which a plurality of webs individually set on a plurality of web holding members are commonly fed, and the plurality of webs are individually provided in the web transport path. A plurality of web feeding mechanisms for feeding are provided, and feeding driving means for selectively driving one of the web feeding mechanisms is provided, and the web feeding mechanism driven by the feeding driving means feeds the web. A single tip detection sensor for detecting the tip of the web is formed in the web transport path,
When the leading edge detection sensor of the web transport path detects the leading edge of the web, the feeding driving means drives the web feeding mechanism in the opposite direction to arrange the leading edge of the web at an initial position. 2. The web transfer apparatus according to claim 1, further comprising: a determination storage unit that stores the feedability determined by the availability determination unit for the web arranged by the feed preparation unit.