1. Field of the Invention
The present invention relates to an image forming system, such as a copier or printer of an electrophotographic type or an electrostatic storage type.
2. Description of the Related Art
Among image forming apparatuses, such as copiers and printers of an electrophotographic type and of an electrostatic storage type, image forming apparatuses wherein a sheet feeding unit is located at the lower portion of the main body have long been known. Further, image forming apparatuses are also known wherein the image forming processing speed can be changed in accordance with the type (the sheet type) of the sheets supplied for image forming (see Japanese Patent Laid-Open Publication No. 2000-305438, corresponding to U.S. Pat. No. 6,301,452).
The sheet conveying operation of an image forming apparatus in
When the sheet type has been identified, the engine controller switches to an image forming condition consonant with the sheet type that was identified (408), and resumes sheet conveying (409). Thereafter, the engine controller outputs a vertical sync signal (a /TOP signal) to permit the controller to output image data (410,
When the sheets employed for this image forming apparatus are plain paper, for example, the feeding speed for registration rollers 15 is set equal to the conveying speed of cassette convey rollers 22a and intermediate convey rollers 23a. When the sheets are thick paper, for example, the feeding speed for the registration rollers 15 is set lower than the conveying speed of the cassette convey rollers 22a and the intermediate convey rollers 23a.
Further, another image forming system is also known wherein, as shown in
In this temporary halted state, the type of sheet is detected by a sheet type detection sensor 12, which is located between the intermediate convey rollers 23b and the registration rollers 15 (611). When the sheet type has been identified, the image forming condition is changed to one in consonance with the identified sheet type (612).
At a predetermined timing, the sheet begins to be conveyed to a transfer conveying belt 9 by the registration rollers 15 and the intermediate convey rollers 23a and 23b (613 and 614), and a vertical sync signal (a /TOP signal) is output to begin the output of image data (615).
When sheets are plain paper, for example, the sheet conveying speed for the registration rollers 15 and the intermediate convey rollers 23a equals the sheet conveying speed for the intermediate convey rollers 23b, and problems, such as the jamming of sheets, do not occur.
However, when sheets are thick paper, for example, the conveying speed for the registration rollers 15 and the intermediate convey rollers 23a is lower than the conveying speed for the intermediate convey rollers 23b, i.e., the conveying speeds are not equal, the jamming of sheets occurs (616;
Accordingly, needed is an improved image forming system and a control method therefore, and a control unit for an image forming apparatus.
Also needed is an image forming system wherein a recording material, supplied from an externally connected feeding unit, can also be normally conveyed, a control method therefor, and a control unit for an image forming apparatus.
Also needed is an image forming system wherein a recording material to which an image has been fixed can also be normally conveyed to an externally connected sheet delivery apparatus, a control method therefor, and a control unit for an image forming apparatus.
The present invention is directed to an image forming system. In one aspect of the present invention, an image forming system including an image forming apparatus and a sheet feeding apparatus, includes: a first conveying unit configured to convey to the image forming apparatus a recording material fed by the sheet feeding apparatus; a second conveying unit configured to convey to an image forming unit of the image forming apparatus the recording material that has been conveyed by the first conveying unit; a detector detecting a type of the recording material while the recording material is halted by the second conveying unit; a first controller, based on detection by the detector, configured to determine a conveying speed for conveying the recording material to the image forming unit of the image forming apparatus, and to convey the recording material at the determined conveying speed; and a second controller controlling speeds at which the first conveying unit is to convey the recording material. Before the recording material fed by the sheet feeding apparatus reaches the second conveying unit, the second controller maintains a first conveying speed for the recording material, and after the recording material reaches the second convey unit, maintains a second conveying speed that the first control unit determines for the conveying of the recording material.
According to another aspect of the present invention, a control method, for an image forming system that includes an image forming apparatus and a sheet feeding apparatus, includes: a first conveying step of conveying a recording material from the sheet feeding apparatus to the image forming apparatus; a determination step of temporarily halting the recording material being conveyed to the image forming apparatus in the first conveying step, and of determining the type of the recording material; a receiving step of receiving information related to a first conveying speed from the image forming apparatus where the first conveying speed is based on the type of the recording material determined at the determination step; and a second conveying step of resuming the conveying of the temporarily halted recording material, in accordance with information related to the first conveying speed.
According to yet another aspect of the present invention, a controller for an image forming apparatus includes: a transmission unit configured to transmit information and a signal to a sheet feeding controller of a sheet feeding apparatus connected to the image forming apparatus; and a control unit detecting a type of recording material to be conveyed to the image forming apparatus, and based on the detected type, determining an image forming speed. Wherein, before detecting the type of recording material, the transmission unit transmits, to the sheet feeding controller, information related to a first conveying speed for the recording material and a sheet feed signal for a recording material start feeding instruction to start the feeding of a recording material, and wherein, after detecting the type of recording material, the transmission unit transmits, to the sheet feeding controller, information related to the image forming speed and a feed resumption signal to instruct feeding resumption of the recording material.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
The embodiments of the present invention will now be described in detail while referring to the accompanying drawings.
The present invention can be applied to an apparatus to which an external apparatus, for which control is provided by a controller, can be connected, and is not limited to an image forming apparatus that employs an electrophotographic process.
A first embodiment of the present invention is illustrated in
The color laser beam printer, which is an image forming system according to this embodiment, includes, as sheet feeders, not only a main body sheet feeding unit 20a but also an external sheet feeding apparatus 20b. When a sheet type is established, a sheet conveying speed (also called an image forming speed) employed during image forming is changed to a sheet conveying speed consonant with the established sheet type.
(General Configuration)
While referring to
The photosensitive drums 1a to 1d, the charging rollers 2a to 2d, the developing devices and the cleaners 6a to 6d are packaged together to form process cartridges 7a to 7d, which are detachable from an image forming apparatus.
A sheet fed from the main body sheet feeding unit 20a or from the external sheet feeding apparatus 20b is conveyed to the image forming section by a transfer and conveying belt 9, which is a conveying device. Then, toner images formed using different colors are sequentially transferred to the sheet to obtain a multi-color image. Thereafter, the image is thermally fixed to the sheet by a fixing device 10, and the resultant sheet is delivered, by a delivery roller pair 14, to a sheet discharge area 13 whereat such sheets are stacked.
(Sheet Feeding Unit)
The main body sheet feeding unit 20a is a unit wherein multiple recording media are stored. The sheets in the main body sheet feeding unit 20a are separately fed, one following the other, by a cassette pickup roller 21a. Each sheet is conveyed to registration rollers 15 by cassette convey rollers 22a and intermediate convey rollers 23a, and is thereafter conveyed, at a predetermined timing, to the transfer conveying belt 9 by the registration rollers 15.
The external sheet feeding apparatus 20b is an optional sheet feeding apparatus, wherein multiple recording media are stored, that is detachable from an image forming apparatus.
The sheets in the external sheet feeding apparatus 20b are separated and fed, one following the other, by a cassette pickup roller 21b, and are individually conveyed to the registration rollers 15 by convey rollers 22b and intermediate convey rollers 23b and 23a. Thereafter, the sheets are individually conveyed, at a predetermined timing, to the transferring/conveying belt 9 by the registration rollers 15.
(Image Forming Section)
The photosensitive drums 1a to 1d are formed by depositing an organic photoconductive (OPC) layer on the outer surface of an aluminum cylinder. Both ends of each of the photosensitive drums 1a to 1d are rotatably supported by flanges, and when a driving force, produced by a drive motor (not shown), is applied at one end of each photosensitive drum 1a to 1d, the photosensitive drums 1a to 1d are rotated counterclockwise, as indicated by arrows in
The charging rollers 2a to 2d are conductive, roller shaped members. When the charging rollers 2a to 2d are brought into contact with the surfaces of the photosensitive drums 1a to 1d and a biased charging voltage, supplied by a power source (not shown), is applied to these members, the surfaces of the photosensitive drums 1a to 1d can be uniformly electrified.
The scanner units 3a to 3d include polygon mirrors toward which image signal consonant image light, emitted by laser diodes (not shown), is directed.
The developing devices respectively include: toner storage units 4a1 to 4d1, in which black, cyan, magenta and yellow toners are respectively stored; supply rollers 4a2 to 4d2, for supplying toner; and developing rollers 4a to 4d, which are positioned adjacent to the photosensitive drums 1a to 1d and are rotated by drivers (not shown), and which perform image development upon the application of a biased development voltage supplied by a biased development power source (not shown).
Further, within an area delimited and defined by the transferring/conveying belt 9, which serves as a conveying device and which will be described below, transfer members 5a to 5d, which contact the transferring/conveying belt 9, are respectively arranged opposite the photosensitive drums 1a to 1d. These transfer members 5a to 5d are connected by a power source (not shown) for applying transfer bias. An electric charge having a positive polarity is applied to a sheet by the transfer members 5a to 5d via the transferring/conveying belt 9. Then, using the thus established electric field, individually colored toner images having a negative polarity, which are formed on the photosensitive drums 1a to 1d, are sequentially transferred to the sheet as it is brought into contact with the photosensitive drums 1a to 1d. In this manner, a multi-colored image can be obtained.
(Sheet Conveying)
After a sheet has been fed by the intermediate convey rollers 23a or 23b, the type of sheet is detected by the sheet type detection sensor 12 located between the intermediate convey rollers 23a and the registration rollers 15. After the sheet type has been identified, the sheet conveying speed is adjusted in consonance with the identified sheet type, and the sheet, which has been held momentarily by the registration rollers 15, is then conveyed to the image forming area by the transfer conveying belt 9.
The transfer conveying belt 9 is extended around and supported by three members, a drive roller 9b and driven rolling members 9c and 9d, which are located opposite the photosensitive drums 1a to 1d. It should be noted that the positioning of the drive roller 9b and the driven rolling member 9c may be inverted, i.e., the members 9b and 9d may be driven rolling members and the member 9c may be a drive roller.
At the most upstream position along the transferring/conveying belt 9, an attraction roller 9e is located for, with the transferring/conveying belt 9, griping a sheet and for attracting the sheet to the transferring/conveying belt 9. During the conveying of a sheet, through the application of a voltage to the attraction roller 9e, an electric field is formed between the attraction roller 9e and the opposite driven rolling member 9c, so that dielectric polarization is generated between the transferring/conveying belt 9 and the sheet, and an electrostatic attraction force is exerted between the two.
The transferring/conveying belt 9 is impelled by the drive roller 9b so that a sheet, electrostatically attracted to the surface of the transferring/conveying belt 9, can be brought into contact with the photosensitive drums 1a to 1d. Thus, at individual transfer positions, the toner images on the photosensitive drums 1a to 1d can be transferred to the sheet that is electrostatically attracted to the transferring/conveying belt 9.
(Fixing Section)
The fixing device 10 fixes a toner image to a sheet by applying heat and pressure, and includes a fixing roller 10a and a flexible pressure roller 10b. By applying a predetermined pressing force, the flexible pressure roller 10b forms, together with the fixing roller 10a, a fixing nip portion N having a predetermined width.
When the fixing nip portion N is adjusted to a predetermined temperature, a sheet to which an unfixed toner image has been transferred is conveyed from the image forming section and is gripped at the fixing nip portion N. Specifically, the sheet is fed between the fixing roller 10a and the flexible pressure roller 10b, with the image side facing upward, i.e., opposite the fixing roller 10a. At the fixing nip portion N, while the image side closely contacts the outer face of the fixing roller 10a, the sheet is gripped and conveyed by the fixing roller 10a through the fixing nip portion N.
During the process through which the sheet is gripped and conveyed by the fixing roller 10a and through the fixing nip portion N, the sheet is heated by the fixing roller 10a, thermally fixing the toner image to the sheet. It should be noted that instead of the fixing roller 10a, another fixing device, such as a film or a belt, may be employed.
Now referring to
The print reservation command is a command including information that designates, for each sheet, a sheet feeding unit, a printing form and a sheet delivery unit, and information relevant to sheet size.
The controller 201 then transmits the print reservation command to the engine controller 203, in accordance with a print instruction received from the host computer 200. When sheets are to be supplied from the external sheet feeding apparatus 20b, the sheet feeding reservation command is also transmitted to the external sheet feeding apparatus controller 202. Furthermore, the controller 201 manages the print reservation command and the sheet feeding reservation command in correlation with each sheet.
Upon receiving the sheet feeding reservation command from the controller 201, the external sheet feeding apparatus controller 202 starts a sheet feeding operation and conveys a sheet to a juncture 24 (see
At the time printing is enabled, the controller 201 transmits a print start command to the engine controller 203.
Upon receiving the print start command, the engine controller 203 conveys the sheet that has been held at the juncture 24 (
In accordance with a sheet convey signal 222 output by the engine controller 203, the external sheet feeding apparatus controller 202 conveys a sheet from the juncture 24 (
In this embodiment, in accordance with the sheet convey signal 222 and the sheet feeding resumption signal 223, the external sheet feeding apparatus controller 202 permits the engine to perform sheet conveying. However, independent signal lines need not always be employed. The sheet conveying may be performed, for example, through communication performed between the engine controller 203 and the controller 201, or through communication performed between the controller 201 and the external sheet feeding apparatus controller 202.
The engine controller 203 includes a CPU 211 and multiple controllers. The CPU 211 manages these controllers and provides control for the entire operation of the engine controller 203.
In
The video interface unit 210 is a transmitter through which the engine controller 203 communicates with or exchanges signals with the controller 201 and the external sheet feeding apparatus controller 202. The above described controllers may be constituted by hardware, such as ASIC, or may be provided as programs that are stored in the ROM in the CPU 211.
The control operations performed by the controller 201, the engine controller 203 and the external sheet feeding apparatus controller 202 will now be explained while referring to
The controller 201 transmits a print reservation command to the engine controller 203 (701) and a sheet feeding reservation command to the external sheet feeding apparatus controller 202 (702).
Upon receiving the sheet feeding reservation command, the external sheet feeding apparatus controller 202 employs the cassette pickup rollers 21b to separate and supply sheets, one by one, from the external sheet feeding apparatus 20b, and employs the convey rollers 22b and the intermediate convey rollers 23b to convey sheets individually to the juncture 24 (see
Upon receiving the notification to prepare for the conveying of sheets, the controller 201 transmits a print start command to the engine controller 203 (705).
When the engine controller 203 receives the print start command from the controller 201 (801), the engine controller 203 prepares to perform printing (706 and 802). Then, the engine controller 203 transmits to the controller 201 speed information related to a sheet conveying speed at which the sheet held at the juncture 24 (see
When the sheet conveying signal has been set to true, the external sheet feeding apparatus controller 202 employs the intermediate convey rollers 23b and 23a to convey the sheet held at the juncture 24 (see
The engine controller 203 permits the sheet type detection sensor 12, located between the intermediate convey rollers 23a and the registration rollers 15, to detect the sheet, for which conveying has temporarily been halted (714 and 807), and to determine the sheet type. Then, the engine controller 203 alters the image forming condition to conform with the established sheet type (including a change to a sheet re-conveying speed that has been correlated in advance) (715 and 808). As a newly designated image forming condition, the engine controller 203 transmits speed information related to the sheet re-conveying speed to the controller 201 (716, 717 and 809), and the controller 201 notifies the external sheet feeding apparatus controller 202 of the sheet re-conveying speed (718). After the transmission of the notification and the preparation of the image forming condition, the engine controller 203 outputs a sheet feeding resumption signal (719 and 810). Here, the sheet re-conveying speed is an image forming speed for forming an image on recording material.
When the sheet feeding resumption signal is output by the engine controller 203, the external sheet feeding apparatus controller 202 resumes the conveying of the sheet by the registration rollers 15 at the previously notified sheet re-conveying speed (720). Thereafter, the engine controller 203 outputs a vertical sync signal (a /TOP signal) to permit the controller 201 to output image data (721 and 811).
As described above, when a sheet is to be conveyed to the registration rollers 15, the speed at which it is conveyed by the convey rollers 22b and the intermediate convey rollers 23b of the external sheet feeding apparatus 20b equals the speed of the conveying performed by the intermediate convey rollers 23a of the main body sheet feeding unit 20a. Further, when the sheet is to be conveyed from the registration rollers 15, the speed at which it is conveyed by the registration rollers 15 and the intermediate convey rollers 23a of the main body sheet feeding unit 20a equals that of the speed at which conveyed by the convey rollers 22b and the intermediate convey rollers 23b of the external sheet feeding apparatus 20b. Therefore, the occurrence, for example, of a paper jam can be prevented and/or reduced in the main body of the engine.
A second embodiment of the present invention differs from the first embodiment in that even when multiple print reservation commands and sheet feeding reservation commands are transmitted in advance, prior to the sequential printing, an engine controller 203 provides for a controller 201 of a sheet conveying speed before and after the sheet type detection is performed for each sheet. Through this processing, the controller 201 can easily determine to which previously, or subsequently, notified sheet conveying speed the detected sheet type corresponds.
Specifically, the feature of this embodiment is that the engine controller 203 either notifies the controller 201 which sheets, designated by which print reservation command, correspond to the conveying speed before the detection of the sheet type, or notifies the controller 201 which sheets, designated by which print reservation command, correspond to the conveying speed after the detection of the sheet type.
For each sheet, correlated with each other, the controller 201 either manages a print reservation command for the engine controller 203 or a sheet feeding reservation command for an external sheet feeding apparatus controller 202. Therefore, based on sheet page information received from the engine controller 203, the conveying speed for each sheet can be obtained.
The control operation performed by the controller 201, the engine controller 203 and the external sheet feeding apparatus controller 202 will now be explained while referring to
The controller 201 transmits a print reservation command to the engine controller 203 (701), and transmits a sheet feeding reservation command to the external sheet feeding apparatus controller 202 (702).
Upon receiving the sheet feeding reservation command, the external sheet feeding apparatus controller 202 begins the pickup process for a sheet, and then conveys the sheet to a junction 24 (see
The engine controller 203 receives the print start command from the controller (705 and 801), prepares to perform printing (706 and 802), and transmits to the controller 201 page information for the sheet being held at the juncture 24 (see
The engine controller 203 thereafter transmits to the external sheet feeding apparatus controller 202, via the controller 201 (1307 and 708), speed information related to the sheet conveying speed for the sheet held at the juncture 24 (see
When the sheet conveying signal is set to true, the external sheet feeding apparatus controller 202 conveys the sheet to the engine main body at the previously notified sheet conveying speed (711).
When the supplied sheet has reached the sheet detection position (712 and 805), the engine controller 203 sets the sheet conveying signal to false (713 and 806), and halts the conveying of the sheet.
The engine controller 203 then detects the sheet type while the conveying of the sheet is temporarily halted (714 and 807). After the sheet type has been determined, the engine controller 203 changes the image forming condition (including the sheet conveying speed) in consonance with the type of sheet identified (715 and 808). Following this, page information for the sheet for which the type has been detected, and speed information related to the sheet conveying speed (the sheet re-conveying speed), consonant with the detected sheet type, are transmitted via the controller 201 (1306, 1324, 717 and 1413) to the external sheet feeding apparatus controller 202 (1325, 718 and 809). After the image forming condition has been changed, the engine controller 203 outputs a sheet feeding resumption signal (719 and 810), to resume the conveying of the sheet, and outputs a vertical sync signal (a /TOP signal) to permit the controller 201 to output image data (721 and 811). Here, the sheet re-conveying speed is an image forming speed for forming an image on a recording material.
When the sheet feeding resumption signal is received, the external sheet feeding apparatus controller 202 resumes the conveying of the sheet at the sheet conveying speed (the sheet re-conveying speed) for which notification was previously received (720).
As described above, even when multiple print reservation commands and print reservation commands have previously been transmitted for sequential printing, for example, the engine controller 203 notifies the controller 201 which sheets correspond to the sheet conveying speed obtained before or after the detection of the sheet type. Therefore, the controller 201 can easily identify which sheets correspond to the sheet conveying speed received before or after the detection of the sheet type, and disagreements as to the sheet conveying speeds, between the engine main body and the external sheet feeding apparatus, can be more appropriately prevented.
This embodiment further differs from the first embodiment in that after the sheet type has been detected, a speed is determined for conveying a sheet to the external sheet delivery apparatus 30, and for this sheet conveying speed, a notification is issued that it matches the conveying speeds of the engine main body and the external sheet delivery apparatus 30, which is an optional sheet delivery apparatus that can be detached from the image forming apparatus.
In
The external sheet delivery apparatus 30 handles a sheet conveyed from a color laser beam printer 900 in accordance with an instruction issued by a controller 201, such as a face up or face down instruction. That is, based on the instruction received from the controller 201, the external sheet delivery apparatus 30 inverts the sheet using a flapper 38, or vertically moves a first discharge bin 35 and a second discharge bin 36, using a bin elevation motor 37, to sort and stack sheets.
When a face up instruction is issued by the controller 201, a sheet is guided by rollers 31 directly to a discharge port. When, however, a face down instruction is issued by the controller 201, a sheet is guided by the flapper 38 to rollers 32 and 33 and is conveyed until the trailing edge of the sheet passes the rollers 32. Then, the rollers 32 are reversely rotated, and beginning with the trailing edge, the sheet is conveyed to rollers 34 and is guided to the discharge port.
Referring to
In accordance with the print instruction received from the host computer 200, the controller 201 transmits a print reservation command to the engine controller 203, and when the sheet is to be delivered to the external sheet delivery apparatus 30, transmits a sheet delivery reservation command to the external sheet delivery apparatus controller 1001. The controller 201 manages, for each sheet, the print reservation command and the sheet delivery reservation command in correlation with each other. When printing is enabled, the controller 201 transmits a print start command to the engine controller 203.
Upon receiving the print start command, the engine controller 203 starts the feeding of sheets, and at the sheet detection position, temporarily halts the feeding operation to detect the sheet type. After the sheet type has been detected, the engine controller 203 resumes the conveying of the sheet, outputs a /TOP signal (221 in
For this embodiment, an explanation will now be given for example processing for the issue of the delivery notice to the external delivery apparatus controller 1001 along independent signal lines. However, the delivery notice may be transmitted along a communication line from the engine controller 203, via the controller 201, to the external sheet delivery apparatus controller 1001. Alternatively, a communication line may be provided between the engine controller 203 and the external sheet delivery apparatus controller 1001, so that the engine controller 203 can directly issue the delivery notice to the external sheet delivery apparatus controller 1001.
Since the engine controller 203 is the same as that in
The control operations performed by the controller 201, the external sheet feeding apparatus controller 202, the engine controller 203 and the external sheet delivery apparatus controller 1001 will now be explained while referring to
The controller 201 transmits a sheet feeding reservation command to the external sheet feeding apparatus controller 202 (1101), a print reservation command to the engine controller 203 (1102), and a sheet delivery reservation command to the external sheet delivery apparatus controller 1001 (1103).
Upon receiving the sheet feeding reservation command, the external sheet feeding apparatus controller 202 begins the pickup of sheets, conveys a sheet to the juncture 24 (see
Thereafter, the engine controller 203 receives a print start command from the controller 201 (1106 and 1201), and prepares to perform the printing (1107 and 1202). Thereafter, the engine controller 203 transmits to the external sheet feeding apparatus controller 202, via the controller 201, speed information related to a sheet conveying speed at which the sheet held at the juncture 24 (see
When the sheet conveying signal is set to true, the external sheet feeding apparatus controller 202 conveys the sheet to the engine main body at the previously received sheet conveying speed (1112).
When the sheet has reached the sheet detection position (1113 and 1205), the engine controller 203 sets the sheet convey signal to false (1114 and 1206) and halts the conveying of the sheet.
The engine controller 203 detects the sheet type while the conveying if the sheet is temporarily halted (1115 and 1207). After the sheet type has been identified, the engine controller 203 changes the image forming condition (including the sheet conveying speed) so it conforms with the sheet type. Then, the speed information related to the sheet conveying speed (the sheet re-conveying speed) consonant with the established sheet type is transmitted via the controller 201 (1116 and 1117) to the external sheet feeding apparatus controller 202 (1118, 1208 and 1209). Further, the speed information related to a speed (a sheet delivery speed) for delivery to the external sheet delivery apparatus 30, which is consonant with the sheet type identified, is transmitted via the controller 201 (1119) to the external sheet delivery apparatus controller 1001 (1120 and 1210).
The engine controller 203 changes the image forming condition (1121), outputs a sheet feeding resumption signal to resume sheet conveying (1122 and 1211), and outputs a vertical sync signal (a /TOP signal) to permit the controller 201 to output image data (1124 and 1212).
When the sheet feeding resumption signal has been output, the external sheet feeding apparatus 20b again starts the feeding of sheets at the previously received sheet re-conveying speed (1123).
When the leading edge of the current sheet has reached the delivery notice position 18 (see
As described above, for a color laser beam printer wherein, after the sheet type has been detected, the speed for conveying the sheet to the external sheet delivery apparatus 30 is determined, disagreements relative to the sheet conveying speed between the engine main body and the external sheet delivery apparatus 30 can be prevented.
A fourth embodiment of the present invention differs from the third embodiment in that, even when multiple print reservation commands and sheet delivery reservation commands are transmitted in advance, for example, for sequential printing, a controller 201 can easily determine which sheets correspond to a sheet delivery speed transmitted by an engine controller 203.
Specifically, after the sheet type has been detected, the engine controller 203 transmits to the controller 201 related sheet delivery speed information that indicates which sheets, designated by which print reservation command, are consonant.
For each sheet, the controller 201 manages a print reservation command, for the engine controller 203, and a sheet delivery reservation command, for an external sheet delivery apparatus controller 1001, that are consonant with each other. Therefore, the controller 201 need only obtain, from the engine controller 203, page information for a sheet, for the sheet delivery speed, for sheets to be delivered to an external sheet delivery apparatus 30, to be obtained.
The control operations performed by the controller 201, the engine controller 203 and the external sheet delivery apparatus controller 1001 will now be described while referring to
The controller 201 transmits a sheet feeding reservation command to the external sheet feeding apparatus controller 202 (1101), a print reservation command to the engine controller 203 (1102), and a sheet delivery reservation command to the external sheet delivery apparatus controller 1001 (1103).
Upon receiving the sheet feeding reservation command, the external sheet feeding apparatus controller 202 begins the pickup of sheets, conveys a sheet to the juncture 24 (see
Then, the engine controller 203 receives a print start command from the controller 201 (1106 and 1201), and prepares to perform printing (1107 and 1202). Thereafter, page information for a sheet held at the juncture 24 (see
The engine controller 203 notifies the external sheet feeding apparatus controller 202, via the controller 201 (1508, 1109 and 1203), of the sheet conveying speed at which the sheet held at the juncture 24 (see
When the sheet conveying signal is set to true, the external sheet feeding apparatus controller 202 conveys the sheet to the engine main body at the sheet conveying speed that has been received (1112).
When the sheet has reached the sheet detection position (1113 and 1205), the engine controller 203 sets the sheet conveying signal to false (1114 and 1206) and halts the conveying of the sheet.
The engine controller 203 then detects the sheet type, while temporarily halting the conveying of the sheet (1115 and 1207). After the sheet type has been identified, the engine controller 203 changes the image forming condition (the sheet conveying speed) so it is consonant with the sheet type that was identified (1208). Then, the page information for the current sheet and the sheet conveying speed (the sheet re-conveying speed) consonant with the sheet type that was determined are transmitted, via the controller 201 (1516, 1528, 1117 and 1615), to the external sheet feeding apparatus controller 202 (1529, 1118 and 1209). Furthermore, the page information for the sheet and the conveying speed (the sheet delivery speed), which is consonant with the sheet type identified, for delivering the sheet to the external sheet delivery apparatus 30 are transmitted, via the controller 201 (1530, 1531, 1119, 1616 and 1210), to the external sheet delivery apparatus controller 1001 (1532 and 1120).
The engine controller 203 changes the image forming condition (1121), outputs a sheet feeding resumption signal (1122 and 1211), to resume the conveying of the sheet, and outputs a vertical sync signal (a /TOP signal) to permit the controller 201 to output image data (1124 and 1212).
When the sheet feeding resumption signal has been output, the external sheet feeding apparatus 20b resumes the conveying of the sheet at the sheet conveying speed (the sheet re-conveying speed) that has previously been transmitted advance (1123).
When the leading edge of the currently conveyed sheet has reached the delivery notice position 18 (see FIG. 8), the engine controller 203 outputs a delivery notice signal to the external sheet delivery apparatus controller 1001 (1125 and 1213). Upon receiving the delivery notice signal, the external sheet delivery apparatus 30 begins preparations to ensure that the sheet, delivered by the engine, is accepted at the sheet delivery speed that was previously received.
As described above, even when multiple print reservation commands and sheet delivery reservation commands are transmitted in advance for sequential printing, for example, the engine controller notifies the controller which sheets are consonant with the sheet delivery speed obtained after the sheet type has been detected. Therefore, the controller can easily identify which sheets are consonant with the sheet delivery speeds received before and after the sheet type detection is performed, and disagreements, relative to the sheet conveying speed, between the engine main body and the external sheet delivery apparatus can be more appropriately prevented.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
Number | Date | Country | Kind |
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2005-126338 | Apr 2005 | JP | national |
2006-095118 | Mar 2006 | JP | national |
This application is a continuation of U.S. patent application Ser. No. 11/409,281 filed Apr. 21, 2006, which claims the benefit of Japanese Patent Laid-Open No. 2005-126338, filed Apr. 25, 2005 and Japanese Patent Laid-Open No. 2006-095118, filed Mar. 30, 2006, all of which are hereby incorporated by reference herein in their entirety.
Number | Date | Country | |
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Parent | 11409281 | Apr 2006 | US |
Child | 12862575 | US |