Patent Application
20110014021
The presently-disclosed embodiments generally relate to methods and systems for transferring articles in a production environment. More particularly, the disclosure relates to transferring articles from a machine to another location.
The embodiments disclosed below relate to devices in which sheets (sheet material including paper, corrugated cardboard, or the like) are processed in a stream and then stacked at the end of a process or machine, generally on a conveyor device that descends as sheets are added to the top of the stack. When the stack is complete or the conveyer device is full, however, the load must be removed, an operation which generally requires the intervention of an operator. If no operator is available, the machine shuts down until one is available.
Consider the example of a finisher for an image forming apparatus such as a copier, a printer, or a facsimile machine. The finisher may perform any number of operations, such as predetermined punching, stapling, and the like. In high-speed, high-volume printers or copiers, print job sets must be frequently unloaded from an output stacking tray. Furthermore, such high volume reproduction machines typically are shared usage or copy center machines, receiving multiple print jobs from many different users, requiring high productivity. Thus, when a job is completed or the output stacking tray is full, the finisher shuts down until an operator attends to it, and the resulting shutdown time causes a loss of productivity.
It would be highly desirable to have a relatively simple and cost effective device for providing a high production customer with the ability to automatically unload consecutive stacks of sheets delivered by a device. Such a solution would allow customers to maintain almost constantly running machines with a minimum number of attending operators, ensuring maximum productivity.
According to aspects illustrated herein, there is provided an apparatus for transferring a load. The apparatus employs a rack, which is vertically movable between a loading position and a rack transfer position. The rack has a ribbed structure, such that the upper surfaces of the rack ribs define a loading surface. Further, a horizontally movable cart in the apparatus can shift between a cart transfer position and an unloading position. The cart, like the rack, is also a ribbed structure including a number of ribs, the upper surface of which defines a pallet surface. The rack ribs and the cart ribs are positioned to intercalate in the respective rack and cart transfer positions. The apparatus also includes a pusher for moving the cart from the transfer position to the unloading position.
Another embodiment disclosed here is a method for transferring a load. The method involves receiving a load on a rack, which is in a loading position. The rack has a ribbed structure. The rack moves the load towards a cart, which also includes a number of ribs. The rack ribs and the cart ribs are positioned to intercalate, allowing for a transfer of the load from the rack to the cart. Having obtained the load, the cart moves to an unloading position, while the rack repositions itself to the loading position.
The following detailed description is made with reference to the figures. Preferred embodiments are described to illustrate the present invention, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a variety of equivalent variations on the description that follows.
According to aspects of the disclosure illustrated here, a machine for transferring a load is described. The machine employs a rack, which is vertically movable between a loading position and a rack transfer position. The rack has a ribbed structure, such that the upper surfaces of the rack ribs define a loading surface. Further, a horizontally movable cart in the apparatus can shift between two positions—a cart transfer position, located directly under the rack, and an unloading position, positioned for convenient off-loading. The cart, like the rack, is also a ribbed structure including a number of ribs, the upper surface of which defines a pallet surface. The rack ribs and the cart ribs are positioned to intercalate in the respective rack and cart transfer positions. The machine also includes a pusher for moving the cart from the transfer position to the unloading position. The machine is designed to allow continuous processing of loads and for minimizing the time for which the machine is idle, waiting for an operator to perform unloading.
The exemplary embodiments discussed below perform certain operations on sheet media within a finisher and then stacks them for output. Various other embodiments, however, can be anticipated to address many different systems or applications in which a load of articles is transferred out of a collection area on a production machine, allowing for an unattended unload and continued operation of the machine.
In this embodiment, the apparatus 100 performs operations on a stream of sheets, and then the sheets are stacked to form a load or stack for output. The apparatus 100 can be associated with any image forming apparatus such as a digital copier, bookmaking machine, facsimile machine, multi-function machine, etc., which performs a print outputting function for any purpose. Moreover, the apparatus 100 may perform any number of operations, such as, predetermined punching, stapling, and similar operations, for each medium, such as a sheet, on which an image is formed by the image forming apparatus.
As used throughout this disclosure, the terms “sheet” or “document” refer to physical sheets of paper, plastic, or other suitable substrate, whether precut or initially web fed and then cut. A “job” is normally a set of related sheets, usually a collated copy set copied from a set of original document sheets or electronic document page images, from a particular user, or otherwise related. It should be understood that the concepts set out here can be employed both in devices handling relatively small sheets, such as paper, as well as apparatus handling large sheets of material such as corrugated cardboard material.
The apparatus 100 includes a vertically movable rack 102 having multiple ribs, referred to as rack ribs 104. Sheets (not shown in
Turning to
Further, as the stack is pushed out of the apparatus 100, it is visibly apparent to an operator that the output stack needs attention. The operator may collect the stack and slide the cart 106 manually into the apparatus 100, making the cart 106 available for the next job. Alternatively, the cart 106 may slide back to the cart transfer position automatically, once the stack has been collected.
The apparatus 100 can be associated with any known image forming device dealing with transfer of a load, allowing for an unattended unload and subsequent loading of another load.
The finisher can be associated with any image forming apparatus such as a digital copier, bookmaking machine, facsimile machine, multi-function machine, etc., which performs a print outputting function. Moreover, the finisher may perform any number of operations, such as, predetermined punching, stapling, etcetera, for each medium, such as a sheet, on which an image is formed by the image forming apparatus.
In the present embodiment, the terms “sheet” or “document” refers to physical sheets of paper, plastic, or other suitable physical substrate for printing images, whether precut or initially web fed and then cut. A “job” is normally a set of related sheets, usually a collated copy set copied from a set of original document sheets or electronic document page images, from a particular user, or otherwise related.
A rack having multiple ribs receives a load (step 602), which includes print media in the present embodiment. The rack is vertically movable between a loading position and a rack transfer position. When the rack is in the loading position, print media such as sheets is stacked onto the rack, which in most applications, sinks as successive sheets are added, converting the stream of sheets into a stack. The sheets collect on the upper surface of this rack, which can move up and down within the finisher. Once the rack is full or the job is complete, the stack of sheets is lowered towards a horizontally movable cart, which in one implementation, is on the floor, beneath the rack. The cart, like the rack, includes multiple ribs and is movable between a cart transfer position and an unloading position.
An elevator system renders the rack vertically movable within the finisher. On sensing that a transfer is required, (which may be triggered by an event such as the completion of a job or the rack being full), the rack is lowered towards the cart, the rack ribs intercalating between the cart ribs, as shown at step 604. Both the rack and cart are in their respective rack and cart transfer positions. The upper surface of the rack ribs drops below the upper surface of the cart ribs on the cart, resulting in a transfer of the stack of sheets to the cart. This ensures a smooth transition of the stack to the cart, and when the cart is repositioned, the entire stack is transported with it, avoiding any sheet slippage or drifting. In an alternate embodiment, the loading surface lies at the level of the pallet surface, and the transfer occurs when the cart is repositioned. Here, the pallet surface has a higher coefficient of friction that the loading surface, for ease of transfer. Further, a sensing device identifying the bottom sheet of the stack is present for providing confirmation that the whole stack is correctly transferred.
The elevator mechanism itself is entirely conventional, scaled to fit the size of the finisher. It is expected that the elevator is controlled by the overall control system of the finisher, operating through conventional solenoid/controller technology or under computer control. Appropriate limit switches and sensors can signal system status to the finisher control system.
After the transfer has occurred, a door on the front of the finisher opens and a pusher including a push plate, a motor, timing belts, slide rods, and switches, pushes the cart outside the finisher to an unloading position at step 606. The stack of sheets is stacked to form a load for delivery to an operator. Further, a switch may energize the motor, which in conjunction with the timing belts and slide rods, drives the push plate, and consequently the cart, in the forward direction.
The front door closes just above the push plate subsequent to pushing the cart outside the finisher. The pusher retracts, and as shown at step 608, the empty rack moves back up to the loading position to start a new job, unattended. In one implementation, the pusher continues to drive the stack of sheets forward until a switch indicating the forward limit is actuated. At this point, the pusher reverses, and the motor begins to drive backward into the finisher.
Further, as the stack is pushed out of the finisher, it becomes visibly apparent to an operator that the output stack needs attention. The operator may collect the stack and slide the cart manually into the finisher, following which, the method 600 can be reinitiated. Alternatively, the cart may slide back into the finisher automatically once the stack has been collected.
The disclosed method 600 can be associated with any known image forming device dealing with transfer of a load, allowing an unattended unload and subsequent loading of another load, thus ensuring higher productivity of the image forming device.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features, that may be specific to particular embodiments of particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination.
Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments.
It will be appreciated that several 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.
