Patent Application
20070289758
An exemplary embodiment of this application will now be described, by way of example, with reference to the accompanying drawings, in which like reference numerals refer to like elements, and in which:
Referring to
In the illustrated apparatus 10 of
The photoreceptor 18 is in the form of a flexible, endless belt having a photoconductive outer surface 13 and is mounted on a set of rollers 26. At least one of the rollers is driven to move the photoreceptor in the direction indicated by arrow 21 at a constant rate of speed about the rollers and past the various xerographic processing stations. Prior to entering the imaging station 24, the photoreceptor surface 13 is uniformly charged at a charging station 28. The exposure of the charged surface of the photoreceptor to the digital signals at the imaging station discharges the photoreceptor surface in the areas struck by the digital image signals. Thus, there remains on the photoreceptor surface a latent electrostatic image in image configuration corresponding to the informational areas on the original. As the photoreceptor continues its movement, the latent electrostatic image thereon passes through developing station 30 where oppositely charged toner is deposited on the latent electrostatic image to form a toner image.
The photoreceptor movement is continued transporting the toner image from the developer station to a transfer station 32. A sheet 15 is fed from a paper supply 33 to a sheet transport 34 for travel to the transfer station. The sheet is moved at a speed in synchronism with the moving photoreceptor and into aligned and registered contact with the toner image. Transfer of the toner image to the sheet is effected and the sheet with the toner image is stripped from the photoreceptor and conveyed to a fusing station 36 having fuser device 16 where the toner image is fused to permanently fix the toner image to the sheet. After the toner image is fixed to the sheet, the sheet is transported by sheet transporting mechanism 37 to a finishing station 12 where the sheets with the permanent images thereon may be compiled into sets of sheets and finished by being stapled by stapler 50.
Suitable drive means (not shown) for the document creating apparatus are arranged to drive the photoreceptor in timed relationship to the scanning of the original document and forming the latent electrostatic image on the photoreceptor, to effect development of the latent electrostatic image, to separate and feed sheets of paper, to transport same through the transfer station in time registration with the toner image, and to convey the sheet of paper with the toner image through the fusing station to fix the toner image thereto in a timed sequence to produce copies of the original documents.
The foregoing description is believed to be sufficient for the purposes of showing the general operation of a high-speed, high-volume document creating apparatus that is capable of producing 100 copies per minute. Thus, it is clear that such high speed, high volume copy producing machines require a finishing device capable of collating and stapling sets of documents varying in size from 2 to 100 sheets.
A typical finishing device 12 for support to a high speed, high volume copier or printer 10 may comprise a sheet transport assembly 38 with diverter gate baffles 39, a sheet guiding and buffering mechanism 14, a compiling and stapling station 40, and a collection tray 42 for storing finished sets of documents. The sheet transport assembly 38 receives and transports sheets 15 from the document creating apparatus 10 along a paper path indicated by arrow 57 to a selected and actuated one of the diverter gate baffles 39. The actuated diverter gate baffle, in cooperation with the drive rollers of the transport assembly 38, divert and deposit the sheet onto the guiding and buffering mechanism in accordance with well known procedure. The sheet guiding and buffering mechanism comprises two elongated retractable arms 44, each being retractable by two arm links 46, onto which sheets are deposited by the transport assembly. The arm surfaces have a slight concave curvature along their length to cause the sheet or sheets deposited thereon to conform to the curvature and create some added beam strength that will prevent the sheets from buckling and slipping between and through the arms prematurely.
As shown in
Staplers should be able to staple a wide range of media thickness used to make up a set of documents, including coated media. In fact, stapling in a range of from 2 sheets to 100 or more sheets per set of documents is common for high volume document creating apparatus. Some staplers may vary the motor force to the stapler based upon the sensed height or counted number of sheets per set of sheets to be stapled. The motor force is then based upon the determination of either a small, medium or thick set of documents with the maximum motor power set for the thickest allowed set of documents and the power proportionally reduced for the sets with lesser number of sheets. However, if the individual weight of the media making up each of the sets of documents varies, then more or less motor power may be required. A set composed of thin sheets requires less motor power to staple than a same sized set of composed of thicker sheets. Also, it is known that coated sheets require more stapling force than plain sheets. Therefore, to assure a successful stapling operation, each category of small, medium and thick sets of sheets must be accomplished by a force required to staple not only the maximum number of sheets in each size category, but also the added force required if each of the sheets in the set were coated and of maximum weight. This extra energy used to assure stapling performance results in a higher wear rate on the stapler, as well as being energy inefficient.
In
The driver assembly 60 is supplied with staples from a staple supply cassette 61. An opening in the cassette is aligned and contiguous with the driver assembly 60. The function of the cassette 61 is to store a ribbon 56 of individual staples that are removably attached together and to feed the staples to the driver assembly 60. The driver assembly 60 moves away from its home position below the stapler support 67 and contacts a staple on the free end of the ribbon of staples 56, shapes it into a U-shape having parallel legs pointing towards the support 67. Simultaneously, the driver assembly drives the staple through an opening 55 in the support 67 and the staple legs through the set of documents residing on support 67. Arms of clincher 58 bend the staple legs protruding through the set of documents towards each other to clinch and fasten the set of documents.
The electrical control circuit 62 includes a memory 68 (shown in dashed line) and is located on the housing 65 below stapler support 67. Various motion control profiles or algorithms are stored in a lookup table in memory 68, each having a power level for the motor 63. Each profile or algorithm causes the clincher 58 to move into contact with and clamp the set of documents on the support 67 and the driver assembly 60 to move from the home position located below the support 67 towards the clincher 58. Continued movement of the driver assembly drives a U-shaped staple through the specifically defined set of documents and simultaneously forms the next staple into a “U.” The arms of the clincher 58 clinch the staple legs protruding through the set of documents. Then the clincher is returned to its spaced position above the support 67 and the driver assembly is returned to its home position. Each profile or algorithm has an empirically determined motor power or energy level required to successfully staple a defined set of documents based upon specific media parameters. Examples of media parameters are paper weight in grams per square meter (g/sm), whether coated or uncoated sheets are used, as well as for specific number of sheets.
An operator or end user inputs the job parameter information, as mentioned above, at the control panel 17 of the document creating apparatus 10. In response to the job parameter information inputted into the control panel, a microprocessor (not shown) in the document creating apparatus associated with the control panel generates a variable start pulse 66 and directs the variable start pulse to the control circuit 62. Each variable start pulse has a specific duration in milliseconds (ms) based upon the job parameter information. As soon as the complete set of documents on the stapler support 67 has been confirmed by any suitable sensing device (not shown), the control circuit responds to the variable start pulse and determines its duration. For either single sheets or collated sets of documents that are not to be stapled, a variable start pulse is not generated.
Each sheet of each set of documents of a job inputted into the control panel 17 by an end user is assigned a value. The values of each sheet for a given set of documents are summed into one total value for the set. Each different summed total value is assigned a variable start pulse having a specific unique duration that represents a specific motion control profile or algorithm that is stored in the memory of the control circuit of stapler 50. For example, a sheet having the weight of 75 g/sm is given the value of 75, plain sheets (not coated) are given a value of 1, and coated sheets are given a value of 2. For a set of 20 plain sheets having a weight of 75 g/sm, the total value is 75×1×20=1,500 and may be assigned, for example, a variable start pulse duration of 25 milliseconds (ms). For the same set of documents but having coated sheets, the total value is 75×2×20=3,000 and may be assigned, for example, a variable start pulse duration of 20 ms. The variable start pulse duration is not aligned to a set thickness. To the contrary, it is aligned to a motion control profile or algorithm stored in memory 68 of the stapler control circuit 62. Thus, a lower variable start pulse duration does not necessarily mean it represents a small or thin set of documents. It is the software designer that establishes what each variable start pulse duration represents and is to be matched to the appropriate motion control profile stored in the control circuit memory.
In another example, a 20-sheet set of documents may have sheets with different media weight with some sheets coated and the rest plain. In this case, 10 sheets are coated and have a weight of 75 g/sm, while the remaining 10 sheets have a weight of 55 g/sm and are plain or uncoated. Thus, the total value is (75×2×10)+(55×1×10)=2,050 and may be assigned a variable start pulse duration of 30 ms. A particular motion control profile would be stored in the memory 68 for a pulse of this duration.
Accordingly, each set of documents in each job entered in the control panel 17 of the document creating apparatus 10 may be different. Therefore, each set of documents in the job may have a different variable start pulse and a different motion control profile that directs the stapling operation by the stapler 50. Whether the number of sheets in each set varies, the weight of the sheets making up the set varies, or if some sheets are coated and some are not coated, a variable start pulse having a specific duration is generated for each different set. Since each variable start pulse duration represents a specific motion control profile, an energy efficient stapling operation is accomplished for each set of the job inputted by the end user.
Because some jobs have a number of identical sets of documents that require stapling, the control circuit 62 also includes a timer 53 that times the speed of the stapling operation carried out by the stapler. If the speed of stapling by the stapler is faster than an empirically determined, optimum time period, also stored in memory 68 for each profile, the control circuit 62 determines too much power was applied to the motor 63. The control circuit then reduces the motor power for the subsequent identical sets of documents to by stapled. Thus, the control circuit 62 compares the stapling speed with the optimum stapling speed for each particular motion control profile stored in memory 68 and determines whether the stapling speed is within acceptable limits of the optimum speed. When the speed limits have been exceeded, the control circuit adjusts the profile for the succeeding identical stapling operation. Accordingly, the motor power may be optimized for subsequent identical sets of documents. Again, it is the job parameter information input by the end user that provides the signal to the control circuit 62 that identifies identical sets of documents by a specific variable start pulse, referred to as a same set pulse. For example, a same set pulse having a duration of 9 ms would mean that the second set of documents in a job are identical to the first set in that particular job.
The stapler control circuit 62 senses the variable start pulse received thereby and determines its duration in milliseconds (ms). The stapler control circuit 62 compares the variable start pulse duration with the various motion control profiles or algorithms stored in a look up table in the memory 68 that are represented by predetermined time periods. One of the profiles stored is memory 68 is matched with the variable start pulse duration sensed by the control circuit. The matched profile is directed to the motor 63 by conductor 69. In response to the profile received by the motor, the motor powers the driver assembly and clincher by suitable gears or timing belt assembly represented by lines 70 and 71, respectively, to complete the stapling cycle. The motor force is thus optimized for stapling each set of documents based upon the job parameter information inputted by the end user.
In
Referring to
After the set of documents has been stapled, the control circuit checks to see if this is the last set of documents in the current job to be stapled at step 90. If the last set of documents in the job has been stapled, the job is ended at step 92. Otherwise, the control circuit checks to see if the next set of documents in the job is identical with the previously stapled set at step 93. If the next set of documents to be stapled is not identical to the previously stapled set, a variable start pulse for the next set of documents is generated at step 94 and sent to the stapler control circuit at step 83.
If the next set of documents to be stapled is identical to the previously stapled set, the speed of the previous stapling operation is compared to the optimum stapling speed stored in memory 68 at step 95. At step 96, the control circuit 62 determines if the stapling speed is within acceptable limits of the optimum stapling speed. If the previous stapling speed is acceptable, the same profile or algorithm is executed at step 98 and sent to the control circuit at step 83. If the stapling speed of the previous identical set of documents is not within acceptable limits of the optimum stapling speed stored in memory, the profile or algorithm is modified to adjust the power to motor 63 at step 97.
It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.
