Patent Application
20060188361
1. Field of the Disclosure
Described herein are devices and methods for manipulating data storage media, particularly devices and methods for transporting storage media between or within storage media libraries.
2. Background
Automated storage systems, including cartridge libraries, are commonly used to store data storage media. One or more individual storage libraries may contain many data storage devices, as well as multiple media drives for reading from, and writing to the storage devices. Automated robotic devices may be used to move storage devices between the various storage cells, and to and from the media drives within the storage library. Individual storage devices may be indexed, and the entire system may be controlled by a device (or devices) capable of coordinating the movement of the storage devices.
One type of storage system includes two or more storage device libraries that may be linked together for coordinated control. With this type of system, each library may include a library housing, a plurality of storage devices (e.g., cartridges) stored in one or more storage device bins within the housing, at least one robotic handling mechanism, and one or more media drives. If multiple libraries are used as part of the same storage system, it may be desirable to coordinate the handling of storage devices between individual storage libraries. Moving storage devices between libraries may help avoid bottlenecks and delays. For example, if many storage devices in a storage library are requested at the same time, delays may result if the number of demanded storage devices exceeds the number of media drives, or the ability of the robotic handlers to process the demand. Thus, it may be desirable to distribute storage devices between libraries. Further, if one or more of the storage device drives in a library fails, it may be desirable to transfer storage devices to another library having functional drives.
Transfer mechanisms have been developed to transfer storage devices between storage libraries. These transfer mechanisms typically include hardware that provides or assists movement of storage devices between individual libraries. In general, simple and inexpensive transfer mechanisms take up useful space within a storage library (e.g., space that could contain other storage bins or media drives). For example U.S. Pat. No. 6,438,623 to Ryan (herein incorporated by reference in its entirety) describes a movable cartridge bin that moves in a straight line between the storage libraries, along a pathway that spans two or more storage libraries, and takes up useful space within the storage library.
Transfer mechanisms must be accessible to a robotic handler (or to some other data storage device manipulators) within each library cavity. However, the transfer mechanism must also move the data storage device between the libraries and avoid interfering with other portions of the library such as the storage bins or media drives. Practically speaking, a robotic handler within a storage library may have a limited range of motion, resulting in a finite amount of useful space within a storage device library that can be accessed by the robotic handler. Thus, it may be desirable to minimize the amount of useful space needed by the transfer mechanism.
Most transfer mechanisms capable of transferring storage devices between storage libraries include a track connecting the storage libraries. The storage device transfer mechanism typically moves in one dimension along the track, and therefore the track must take up useful space within the library cavity so that the transfer mechanism can be accessed by a robotic handler. For example, U.S. Pat. No. 5,760,995, U.S. Pat. No. 6,648,574, U.S. Pat. No. 6,751,040, U.S. Pat. No. 5,700,125, U.S. Pat. No. 6,574,173, and U.S. Pat. No. 6,438,623 describe transferring storage devices that move in only one dimension down a track. All of these references are herein incorporated by reference in their entirety.
Accordingly, there is a need for a simple storage device pass-through transfer mechanism. In particular, there is a need for a storage system that has a storage device pass-through transfer mechanism that provides two-dimensional motion from a single (e.g., one-dimensional) driver. None of the cited prior art suggests the device and methods described and claimed below.
Described herein are storage device transport systems, including transporters, tracks, cam pathways, and methods of using them. These storage device transport systems may transfer storage devices (e.g., cartridges) between two or more storage libraries. Typically, the storage system comprises a transporter having a shuttle for holding a storage device. The transporter may be moved within or between storage libraries of a storage system, and may move in two dimensions (e.g., an x, y plane) by following a cam pathway, and thereby extend or retract to provide a robotic handler with access to the shuttle.
Storage device transport systems for transporting a storage device are described herein. The storage device transport system may include a transporter for transporting a storage device, wherein the transporter comprises: a shuttle for holding a storage device; a carrier platform, wherein the shuttle is moveably connected to the carrier platform so that the shuttle may move with respect to the carrier platform; and a cam follower for following a cam pathway. The cam follower may be configured to move the shuttle with respect to the carrier platform. In some versions, the cam follower moves within a guide track in the carrier platform. The cam follower may comprise a roller, or a ball bearing.
The storage device transport system may also include a track extending longitudinally. The track may include a cam pathway (in this case, a “track cam pathway” because it is a cam pathway that is part of the track) that extends longitudinally and laterally along the track. Thus, the track cam pathway may traverse the track in a curved or shaped pathway. For example, the cam pathway may move laterally (from side to side across the width of the track) as the track extends longitudinally. The cam follower may be configured to follow the track cam pathway. The track may be modular and configured to mate with a second track so that the track cam pathway continues from the track to the second track. The track may extend longitudinally for connecting a first storage library to a second storage library. Thus, a first storage library may be connected to a second storage library by a track, and the transporter may follow the track from the first storage library to the second storage library.
The storage device transport system may include a driver for moving the transporter along a track. The driver may comprise a belt.
Also described herein are storage device transport systems for transporting a storage device that include: a track extending longitudinally, wherein the track includes a cam pathway that extends longitudinally and laterally along the track; a transporter (comprising a shuttle, a carrier platform and a cam follower) for transporting a storage device; and a driver for moving the transporter longitudinally along the track. The position of the shuttle may correspond to the position of the cam follower following the cam pathway as the transporter is moved longitudinally along the track so that the carrier platform moves in the longitudinal direction of the track and the shuttle moves both longitudinally and laterally.
In some versions, the track of the storage device transport system may extend longitudinally to connect a first storage library to a second storage library.
Also described herein are tracks for connecting a first storage library and a second storage library, wherein the track extends longitudinally and includes a cam pathway extending longitudinally and laterally along the track. The track may be modular, so that the track is configured to mate with a second track so that the track cam pathway continues from the track to the second track.
Also described herein are transporters for transporting a storage device. The transporter may include: a shuttle for holding a storage device; a carrier platform configured to move longitudinally, wherein the shuttle is moveably connected to the carrier platform so that the shuttle may move with respect to the carrier platform; and a cam follower for following a cam pathway, wherein the cam follower moves the shuttle with respect to the carrier platform as the carrier platform moves longitudinally.
The transporter may have a first position in which the shuttle is extended, and a second position in which the shuttle is retracted. The cam follower may move the transporter from the first position to the second position as the carrier platform moves longitudinally.
Also described herein are methods of transporting a storage device from a first storage library to a second storage library, the method that include: moving a transporter holding a storage device. The transporter may include: a shuttle; and a cam follower for following a cam pathway, wherein the cam follower follows a cam pathway. The method may also include loading a cartridge into the shuttle of the transporter.
Other features and aspects of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings that illustrate, by way of example, the features in accordance with embodiments of the invention. The summary is not intended to limit the scope of the invention, which is defined solely by the claims attached hereto.
Described herein are devices, systems and methods for transferring storage devices (e.g., devices comprising storage media) from one storage library (e.g., a library containing multiple storage devices such as cartridges) to another storage library. The following descriptions of specific materials, techniques, and applications are provided only as examples. Various modifications to the examples described herein will be readily apparent to those of ordinary skill in the art, and the general principles defined herein may be applied to other examples and applications without departing from the spirit and scope of the invention. Thus, the present invention is not intended to be limiting to the examples described and shown, but is to be accorded the scope consistent with the appended claims. The term “storage device” is used to describe any type of data storage device (including different storage media), and is not intended to be limited to one particular type, and includes tape media storage devices, optical media storage devices, solid-state storage devices, and any combination thereof, or any other embodiment of a data storage device. Although the examples of storage devices provided herein are predominantly tape cartridges, it should be understood that any appropriate type of storage device may be used.
In general, a storage device transport system may be used to transport one or more storage devices (e.g., cartridges) between two or more storage libraries. Storage device transport systems may also be used to transfer storage devices within a storage library. A storage library may include multiple storage bins for holding storage device, media drives for reading and/or writing to the storage devices and a storage device manipulator, such as a robotic picker or arm. An example of a storage library may be found in U.S. Pat. No. 5,760,995 to Heller et al., herein incorporated by reference in its entirety.
A plurality of storage libraries may be linked at coordinated pass-through regions. The pass-through regions allow a transporter carrying a storage device to move from one storage library to another (usually adjacent) storage library. A track may link all of the storage libraries, and may extend through the pass-through regions and within each storage library. A drive (such as a cable or belt drive) may be used to move the transporter along this track as it moves between and within storage libraries. A control system may be used to control the motion of the transporter so that the transporter may carry storage devices from a first storage library into a second storage library. Furthermore, the transporter may be positioned so that a storage device may be loaded or unloaded from the transporter by a robotic picker within a storage library. A cam pathway may be used to position the transporter so that it can be loaded by a robotic picker and then moved into another storage library.
Thus, a storage device transport system may comprise a transporter. The transporter typically comprises a cam follower connected to a shuttle region (shuttle). The shuttle of the transporter may hold a data storage device (e.g., a cartridge). The storage device transport system may include a track having a cam pathway. The track may span a plurality of storage libraries. The storage device transporter may comprise a driver. A driver may move a transporter between (or within) storage libraries by propelling the transporter in a longitudinal directions (e.g., the direction that a track extends). Although the driver may move the transporter in one dimension (e.g., forward or backward along a track), the cam pathway and the cam follower may move at least the shuttle of the transporter in additional directions (e.g., at an angle to the direction of the track), allowing the shuttle of the transporter to move in two dimensions (e.g., in an x, y plane), even if the driver only moves in one dimension. As the driver moves the transporter along the track, the cam follower follows the cam pathway and moves shuttle of the transporter. In this way, the cam follower and the cam pathway may translate the one-dimensional movement of a single driver into two-dimensional movement, and thereby precisely position the shuttle of the transporter.
Transporter
A storage device transport system may comprise a transporter. The transporter may be used to carry a storage device such as a cartridge between a first and a second storage library, and may comprise a shuttle and a cam follower. The entire transporter may move within and between storage libraries. In some versions, a portion of the transporter is configured to move in the direction of a track spanning at least a plurality of storage libraries. For purposes of simplicity, the direction of a track spanning a plurality of storage libraries may be thought of as longitudinal (e.g., along the back side of a storage library). A driver may be used to push the transporter in the direction of the track, as described further below. A transporter may also be configured so that the transporter (or a region of the transporter) may move in a direction other than longitudinal. For example, the transporter may be configured to move at an angle to the longitudinal direction. Thus, a portion of the transporter (e.g., the shuttle) may move laterally. “Lateral,” in this sense may be perpendicular to the longitudinal direction (e.g., the direction of the track). Movement in the lateral direction may therefore mean movement having a component that is perpendicular to the longitudinal direction. For example, any motion in a direction that is not parallel to the longitudinal direction has a component that is lateral. In some cases, “lateral” motion may mean motion that is only perpendicular to longitudinal.
Thus, the transporter may be moved laterally. The transporter may comprise different regions that.are configured to move in different directions. In some versions, the transporter comprises a carrier platform that is configured to be moved (e.g., longitudinally) by a driver, and a shuttle that is configured to be moved (e.g., laterally) by a cam follower. The shuttle may be moveably (e.g., slideably) connected to the carrier platform, and supported by the carrier platform, so that the shuttle moves with the carrier platform in the direction of the driver and the shuttle also moves relative to the carrier platform to extend or retract the shuttle.
The shuttle 101 of the transporter 100 shown in
The transporter may further comprise a cam follower 110. The cam follower contacts a cam pathway, and may move the shuttle 101 with respect to the carrier platform 110 as directed by the cam pathway. In general, the cam follower comprises a contact bearing having a surface that is configured to contact a cam pathway. In some versions, the contact bearing is attached to a post, or comprises a region of a post projecting from the shuttle. In
The cam follower may be held in a guide track (e.g., a channel) 140 region of a carrier platform 120, as shown in
The cam follower and/or the guide track may be configured to minimize friction between the guide track 140 and the cam follower. For example, the cam follower (e.g., a post region of a contact bearing) may be configured to rotate or may comprise a low-friction surface. In some versions, the points of contact between the cam follower and a guide track (or the cam pathway) comprise a low-friction surface, or may otherwise facilitate motion between the cam follower and the contact surface. In some versions, the cam follower further comprises a guide assist (e.g., a spring, a locking mechanism, a supporting structure, etc.) to hold the cam follower within the cam pathway and/or a guide track.
In general, any appropriate driver may be used to move the transporter in the direction of the track. In some versions, the storage system comprises only a single driver for moving and positioning the transporter. The driver may comprise a motor, a gear system, a cable system, a rotatable shaft, etc. The driver may be configured so that it is attached to the transporter, or it may not continuously, or directly, contact the transporter. The driver connectors (e.g., belts) shown in
Slider Device
A slider device may extend and retract along two or more approximately parallel shafts. For example, the shuttle may be a slider device configured to extend and retract from the carrier platform along two approximately parallel shafts 405, 405′, as shown in
In some versions, a slider device comprises a slider frame having two approximately parallel shafts that are elastically mounted to the slider frame. Each shaft may be slideably disposed within a shaft support. The shaft support may be fixed in place (e.g., by being fixed to a carrier platform, or part of a carrier platform). The slider device may have a high misalignment tolerance because the shafts are elastically mounted to the slider frame, providing radial compliance at both ends of the shafts. The radial compliance may compensate for small (e.g., less than 10 degrees, less than 5 degrees, less than 1 degree, or less than 0.25 degrees) concentric misalignments.
Because of the radial compliance, the shafts may be approximately parallel. In some versions, the shafts are parallel. In some versions, the shafts are slightly off-axis from each other (e.g., not parallel). In some versions, the angle between the long-axis of two of the shafts is less than 10 degrees. In some versions, this angle is less than 5 degrees. In some versions, this angle is less than 2.5 degrees. In some versions, this angle is less than 1 degree. In some versions, this angle is less than 0.25 degrees. The radial compliance of the shafts may depend upon the mounting. For example, more compliant elastic mountings may result in more radially compliance in the shaft.
The shafts may be any appropriate material for supporting the slider frame, and permitting an elastic mounting to the slider frame. For example, the shafts may comprise the same material as the slider frame. The shafts may comprise a stiff material. In some versions, the shafts may comprise an elastic material. For example, the shafts may comprise a layer of an elastic material, particularly at the ends which are mounted to the slider frame. Thus, the sliders may comprise a plastic, a ceramic, a metal, or any appropriate combination thereof.
The shafts may be elastically mounted to the slider frame in any appropriate fashion. For example, the shafts may be surrounded by an elastic material at the attachment sites, or the shafts may themselves comprise an elastic material, particularly at these sites. In some versions, a shaft mounting comprises an elastic O-ring. In some versions, the shaft mounting comprises elastic bearings. In general, elastic materials are capable of returning to an initial form or state after deformation. Examples of elastic materials may include, but are not limited to, rubbers, elastomers, (e.g., polyisoprene, natural rubber, polybutadiene, polyisobutylene, urethanes and polyurethanes, etc.).
Thus, a slider device may compensate for variations in the center distances (e.g., misalignments) that may arise during the assembly or operation of the slider device. The shafts may be elastically mounted to the slider frame so that the shafts may move slightly within the slider frame mount when a force is applied to the slider frame (including the shafts). For example, if both shafts are not aligned perpendicular to the channel through the shaft support when extending or retracting the slider device, the elastic mounting of the shafts to the slider frame may permit movement of the shafts within the shaft supports, and thereby permit movement of the slider frame.
The shafts may be supported by one or more fixed shaft supports that allow the shafts (and therefore the slider frame to which the shafts are flexibly mounted) to be movable within the shaft supports. In some versions, the shafts are slideably movable within the shaft supports. The shafts and/or the shaft supports may also comprise a low-friction surface to decrease friction between the shafts and the shaft supports. Thus, the shaft support may comprise a material having a low friction with respect to the shafts, or it may be coated with such a material (e.g., a lubricious material). In some versions, the shaft supports comprise a lubricant to decrease friction between the shafts and the shaft supports. The shaft supports may comprise bushings that are fixed with respect to the slider frame and shafts. For example, a carrier platform may comprise shaft supports 420, as shown in
The O-ring 601 shown in cross-section in
In
The shaft may be secured within the shaft mount by a holdfast.
In some versions, the slider frame of the slider device may further comprise a slider frame support to limit the motion of the slider frame in a direction that is at an angle to the long axis of the approximately parallel shafts. For example, in
Track
A track may span one or more adjacent libraries. The track may comprise a cam pathway for guiding at least a shuttle of the transporter. In general, a track connects two or more storage libraries. That is, the track may comprise a straight-line connection between adjacent storage libraries. One or more portions of the transporter may be connected (e.g., with a movement-allowing connection) to the track, including the cam follower.
In some versions, the track comprises one or more rods (e.g., cylindrical rods) at different levels with respect to the horizontal plane of the storage library that may support the transporter (e.g., within the carrier platform). These rods may comprise any appropriate material (e.g., metal, plastic, etc.) and may include a lubricious, low-friction surface or a lubricant. The track may comprise a shelf region to hold the cam pathway. The track may be positioned within the storage libraries to be out of the way of the “useful space” in the storage library. Thus, the track may be positioned so as not to interfere with bins for cartridges (or any other appropriate storage media) or media drives. For example, the track may be positioned in an area otherwise inaccessible to the storage media manipulators such as robotic pickers, or other components of the storage library.
The track may be segmented. For example, the track may span one, two, or more than two libraries, and additional “modules” of the track (including the cam pathway and support rods) may be added as additional libraries are added. Portions of the track (e.g., the cam pathway, the rods, etc.) may be attached at various points within each connected library. Furthermore, additional segments may be added to the track to connect additional storage libraries. In
Storage Systems
The transporters, tracks and slider devices described herein may be used as part of a system of managing, storing, saving and retrieving data from data storage devices. In particular, transporters and tracks may be used as part of a library storage system such as those described in U.S. Pat. No. 5,760,995, U.S. Pat. No. 6,766,412, and U.S. Pat. No. 6,097,566, herein incorporated by reference in their entirety.
In general, the a storage system may comprise a track connecting two or more storage libraries. The track may include a cam pathway that may guide a cam follower on a transporter, thereby helping to control the location of the shuttle of the transporter. The cam pathway and cam follower may allow precise positioning of the shuttle to permit storage systems to transport data storage media between storage libraries.
The shuttle of the transporter receives and holds data storage devices (e.g., cartridges) so that they may be transported between storage libraries. Typically, a robotic handler (e.g., a robotic picker) is used to manipulate storage media within each storage library. A cam pathway and a cam follower may position the shuttle of a transporter so that it can be accessed by a robotic picker within each storage library. In one version, the cam pathway and cam follower causes the shuttle to extend, allowing a robotic picker access to the opening and holding bin portions of the shuttle. For example, a cam pathway as shown in
The track may be positioned in any appropriate position within each connected storage library.
In
The storage system may also include one or more sensors for detecting the position or status of components of the storage system, such as the transporter or track. For example, sensors may report the location of the transporter (e.g., its location within any particular library storage cavity, whether it is in a predetermined position, etc.), the status of the shuttle (e.g., determining whether a storage device is present, which storage device is present, the position of the shuttle, etc.), and the amount of force being applied to translate the transporter (e.g., to prevent damage, or provide feedback). In one version, the data storage system comprises sensors for detecting the position of the transporter within the storage system.
Any appropriate sensor may be used, including optical sensors (e.g., cameras, light diodes, etc.), mechanical sensors (e.g., pressure), and the like. Multiple sensors may be used to perform different, related, or overlapping functions. Sensors may be connected to a central controller, or they may be used in limited control loops. In some versions, each storage library has a controller (e.g., a system controller board) which may be coordinated with the controllers of the other libraries within the storage system or with an overseer controller for coordinating activity within all of the libraries, including passing storage devices between libraries and tracking data storage media within the storage system. Controllers may communicate with each other by IR connections, by cables, or by any other appropriate means. In one version, a central controller may be used to control the storage system. Any of the controllers may include inputs and outputs for interaction with users.
Operating the Storage System
Described herein are slider devices that may be used to extend or retract a slider frame, despite some misalignment. The slider devices may be incorporated into storage systems that may be used to transfer storage devices between two or more storage libraries.
In operation, a slider device may extend or retract a slider frame (e.g., a shuttle), along two or more approximately parallel shafts that are elastically mounted to the slider frame when the shafts are each slideably disposed within a fixed shaft support. Force may be applied to slide the slider device. In some versions, a force is applied to move the slider from a direction that is not approximately parallel with the long axis of one of the shafts, causing misalignment.
One or more portions of a storage system, such as the shuttle of a transporter, may be configured as a slider device. In operation, a storage system may connect multiple storage libraries, and allow passage of storage devices between the storage libraries. A transporter comprising a shuttle and a cam follower may be moved along a track connecting two or more storage libraries so that the cam follower follows a cam pathway region of the track. A driver may move the transporter within and between the storage libraries. Thus, a cartridge or other appropriate storage media may be transferred between storage libraries using the storage system.
For example, a cartridge from a first library may be placed within the shuttle of the transporter (e.g., by a robotic picker), and the transporter may be moved from the first library to a second library. As the transporter is moved, the cam follower may position the shuttle by following the cam pathway. Thus, when the cartridge is loaded into the shuttle, the shuttle may be extended towards the front of the storage library, towards the robotic picker, because the cam pathway is curved towards the front of the storage library at this point along the track (relative to the rest of the cam pathway). The cam pathway may curve towards the back of the track (away from the robotic picker) over the portion of the track extending from the loading/unloading position in the first library and a loading/unloading position in the second library. As the transporter is moved from the starting position towards the second library, the cam follower will follow the cam pathway, and therefore retract the shuttle. Thus, the shuttle is moving both along the track towards the second library, and towards the back of the library system, away from the robotic picker. The retracted position may make it easier for the transporter to maneuver within the cavity of a storage library.
A portion of the cam pathway within the second library may curve towards the front of the library, closer to the robotic picker (e.g., corresponding to a load/unload position for the transporter within the second library). Once the transporter has moved into the second storage library, the cam follower (following the cam pathway) will extend the shuttle of the transporter towards the front of the second storage library, positioning the shuttle so that the robotic picker may remove or insert a cartridge from the shuttle. Thus, the shuttle may be precisely positioned by the cam follower, following the cam pathway.
The above detailed description is provided to illustrate various examples and is not intended to be limiting. It will be apparent to those of ordinary skill in the art that numerous modification and variations within the scope of the present invention are possible. For example, various examples described herein may be combined and altered. Further, numerous other devices and processes not explicitly described herein may be used with the exemplary storage device holders and extensible supports described, as will be recognized by those of ordinary skill in the art. Furthermore, the description has discussed particular examples as well as ways in which these examples may address certain disadvantages in related art. This discussion is not meant, however, to restrict the various examples to methods and/or systems that actually address or solve the disadvantages. Accordingly, the present invention is defined by the appended claims and should not be limited by the description herein.
