Library apparatus, library system and medium transportation method of library apparatus

A library apparatus includes a housing having an opening, a cell unit including a plurality of cells for storing a storage medium, a drive unit for writing data into or reading data from the storage medium, a medium transportation unit for accessing each of the cells and the drive unit and for transporting the storage medium between the cells and between each of the cells and the drive unit, a cell unit driver for moving the cell unit in vertical direction, and a controller for driving the cell unit driver to move the cell unit through the opening to a position accessible by a medium transportation unit of another library apparatus stacked in vertical direction.

FIELD

The embodiments discussed herein are related to a technology for a library apparatus, a library system and a medium transportation method of the library apparatus.

BACKGROUND

In a library system that a plurality of library apparatuses are only stacked, a storage medium is incapable of being transported between the library apparatuses. Therefore, while a drive unit of a first library apparatus of the library apparatuses is used, even if a second library apparatus of the library apparatuses has a drive unit which is not used, the drive unit which is not used is incapable of being used by the first library apparatus. Therefore, operation rate of the library system is low. Then, the library apparatus equipped with a medium transportation mechanism is developed. It enables the transportation of the storage medium between the library apparatuses. For instance, the medium transportation mechanism that provides a new elevator mechanism for transporting the storage medium between the stacked library apparatuses is well-known. A portion of space for cells and drive units arranged along movement area of a robot is used for the new elevator mechanism. U.S. Pat. No. 5,870,245 is an example of conventional technique.

A portion of space for the drive units and the cells in each of the library apparatuses is occupied for an area where an elevator moves. Therefore the number of the storage mediums which are mounted in the library apparatus equipped with the medium transportation mechanism decreases comparing with that of the library apparatus that is not equipped with the medium transportation mechanism.

SUMMARY

According to an aspect of the invention, a library apparatus includes a housing having an opening, a cell unit including a plurality of cells for storing a storage medium, a drive unit for writing data into or reading data from the storage medium, a medium transportation unit for accessing each of the cells and the drive unit and for transporting the storage medium between the cells and between each of the cells and the drive unit, a cell unit driver for moving the cell unit in vertical direction, and a controller for driving the cell unit driver to move the cell unit through the opening to a position accessible by a medium transportation unit of another library apparatus stacked in vertical direction.

DESCRIPTION OF EMBODIMENT

Hereinafter, a library apparatus and a library system according to an embodiment is described in detail with reference to the accompanying drawings.

FIG. 1illustrates a block diagram of a library system61. The library system61includes a plurality of library apparatuses1which are stacked in a vertical direction. One of the library apparatuses1is connected with a host51. The remaining other library apparatuses1are not connected with the host51. On the other hand, the library apparatuses1are connected with each other.

The library apparatus1includes a controller2, a drive unit3, a cell unit21, a cartridge access station6(hereinafter referred to as CASE), a robot7, a storage medium10, and a cell unit driver11.

The controller2performs a control of the library apparatus1. For instance, when the controller2receives from the host51an instruction for writing data into the storage medium10or reading data from the storage medium10, the controller2controls the robot7to move to a cell5where the storage medium10having an identification number instructed by the host51is stored. Next, the controller2controls the robot7to remove the storage medium10from the cell5, to transport the storage medium10to the drive unit3and to set the storage medium10in the drive unit3. And, after the data is written into or read from the storage medium10, the storage medium10is removed from the drive unit3, transported to the original cell5and stored in the original cell5. When the controller2moves the storage medium10to one of other library apparatuses1, the controller2drives the cell unit driver11and moves the cell unit21. At this time, the controller2transmits a control data through an interface to the one of other library apparatuses1. The control data is, for instance, a drive unit number instructed from the host51, the identification number of the storage medium10for being transported, an instruction for moving the cell unit21and the instruction for writing date into or reading data from the storage medium10.

The drive unit3is a magnetic tape drive unit that writes data into or reads from the storage medium10. The cell unit21includes a plurality of the cells5that are arranged in matrix shape. The CAS6is a mechanism to load the storage medium10into the library apparatus1or to eject the storage medium10from the library apparatus1.

The robot7is a medium transportation unit to access and to transport the storage medium10between the drive unit3and the cell5, between the cell5and the cell5, or between the cell5and the CAS6. Moreover, the robot7has a CCD sensor8for detecting the identification number of the storage medium10and a hand9for holding the storage medium10. The CCD sensor8is equipped with the hand9and scans the bar-code label put on the storage medium10to read the bar code. And, the read data is transmitted to the controller2. A bar-code data is, for instance, the identification number of the storage medium10. The hand9stores the storage medium10into the cell5, and removes the storage medium10from the cell5.

For instance, the storage medium10is a cartridge tape that the magnetic tape rolled in the reel is set in a case. A bar-code label that the identification number is printed is put on the back side of the storage medium10. The cell unit driver11drives the cell unit21in the vertical direction.

FIG. 2illustrates a block diagram of the controller2. The controller2includes a CPU31, a memory32, a robot controller33, a drive controller34, a communication controller35and a cell unit controller36. The CPU31is a processor. And, the CPU31performs a control of the library apparatus1by controlling the memory32, the robot controller33, the drive controller34, the communication controller35, and the cell unit controller36. For instance, the CPU31performs processing that transports the storage medium10from one library apparatus1to another library apparatus1. Moreover, the CPU31performs each processing according to a control program stored in the memory32. The memory32stores various programs and various data of the library apparatus1. The robot controller33drives the robot7, and moves the robot7to the cell5where the storage medium10having the identification number instructed from the host51is stored. Next, the robot7removes the storage medium10, transports the storage medium10to the drive unit3, and set the storage medium10in the drive unit3. And, after writing data into the storage medium10or reading data from the storage medium10is completed, the robot7removes the storage medium10from the drive unit3and transports the storage medium10to the original cell5to store the storage medium10in the original cell5. The drive controller34controls to write data into the storage medium10or to read data from the storage medium10. The communication controller35controls to communicate with the host51and other library apparatuses1. The cell unit controller36controls the cell unit driver11to drive the cell unit21. For instance, the cell unit controller36moves the cell unit21to the position where the robot7of a nearby other library apparatus1that are stacked in the vertical direction is capable of accessing.

FIGS. 3A and 3Bschematically illustrate a top view of the library apparatus1.FIG. 3Aschematically illustrates a transparent top view of the library apparatus1. InFIG. 3A, the cell unit21that stores the storage mediums10is arranged at both right and left sides in the library apparatus1. And the drive unit3is arranged at back side in the library apparatus1inFIG. 3A. The drive units3are stacked in the vertical direction. The robot7is arranged at the center of the library apparatus1. As the robot7moves in a front-back direction and in an up-down direction, rotates in a right-left direction, the robot7has a structure accessible to the cell5of the cell unit21and the drive unit3. The cell unit driver11is arranged, for instance, only on a left cell unit21inFIG. 3A. Moreover, the cell unit driver11may be arranged only on a right cell unit21or on both the right cell unit21and the left cell unit21. Moreover, a housing12of the library apparatus1is in a rectangular parallelepiped shape.

FIG. 3Bschematically illustrates a top view of the housing12of the library apparatus1. Two openings41are formed in the top plate of the housing12of the library apparatus1as illustrated inFIG. 3B. The cell unit21moves into other library apparatus1through the openings41. When the cell unit21is moved downward, the openings41are also formed in the bottom plate of the housing12of the library apparatus1. In the case where the openings41are not used, plates for covering the openings41are provided.

FIG. 4schematically illustrates a transparent front view of the library apparatus1. For instance, the CCD sensor8is mounted underneath the hand9of the robot7. The CCD sensor8may be also on or within the hand9.

An accessible position of the robot7is a position that the hand9can access the storage medium10and the CCD sensor8can read the bar-code label of the storage medium10. Therefore, when the CCD sensor8is mounted on or underneath the hand9, a space42and a space43that the robot7is incapable of accessing the storage medium10are formed. The space42and the space43are formed at an upper portion and a lower portion of the library apparatus1, respectively. Moreover, even if the CCD sensor8is mounted within the hand9, as a space is needed for arranging the robot7in the library apparatus1, the space42and the space43are formed at a position that the robot7is incapable of accessing the storage medium10. Moreover, the space42and the space43are used as retraction areas of the cell unit21. Moreover, since a cell unit21of a nearby other library apparatus1moves to the accessible position of the robot7in the self-library apparatus1, it is needed that the self-library apparatus1has the retraction areas which are formed so as to have height enough to retract a portion of the cell unit21of the self-library apparatus1. And, when the cell unit21of the nearby other library apparatus1moves to the accessible position of the robot7of the self-library apparatus1through the opening41, the cell unit controller36of the self-library apparatus1controls to drive the cell unit driver11and to move the portion of the cell unit21of the self-library apparatus1into the space42or the space43of the self-library apparatus1.

The space42is an area between the upper surface of housing12and the upper surface of cell unit21. The space43is an area between the bottom of housing12and the bottom of cell unit21. Each of the space42and the space43is used as the retraction area of the portion of the cell unit21. As a result, when the library apparatuses are stacked, it can be avoided that the cell unit1protrudes out of the opening41of the uppermost library apparatus1or the lowermost library apparatus1.

The cell unit21can be moved in the vertical direction of the library apparatus1by the cell unit driver11. For instance, the cell unit driver11is mounted only on the left cell unit21. And the cell unit driver11, which allows the cell unit21to move in the vertical direction, can be realized by various methods.

FIG. 5illustrates an explanatory diagram of the cell unit21. The cell unit driver11is mounted on the cell unit21as illustrated inFIG. 5. The arrow indicates that the cell unit21moves in the vertical direction.

FIG. 6illustrates an explanatory diagram of the cell unit driver11. The cell unit driver11is mounted on the housing12of the library apparatus1by fixing a base11awith a screw. A motor11bis mounted on the base11a. The driving force of the motor11bis transmitted to a pulley11dthrough a belt11c. A ball screw shaft11eis coaxially fixed to the pulley11dso as to rotate with the pulley11d. The ball screw shaft11eand the pulley11dare rotatably mounted on the base11athrough a bearing.

Moreover, a shaft11his mounted on the base11a. A block11gis coupled with the shaft11hthrough a direct-acting bearing or a bush. And, the block11gis coupled so as to be movable in the axial direction of the shaft11h. Moreover, the block11gis fixed to a nut11fof the ball screw with the screw. The block11gmoves in the direction of an arrow with the nut11fof the ball screw, when the ball screw shaft lie rotates by driving the motor11b.

The cell unit21is fixed to the block11gwith the screw, and moves in the vertical direction of the library apparatus1with the block11gby driving the motor11b. Moreover, if guides such as a recess and a protrusion which are fitted with each other between the housings12and the cell unit21are provided, the inclination of the cell unit21can be suppressed. Though the number of columns of the cells in the cell unit21is 3 columns as illustrated inFIG. 5, the same mechanism can be used even if the cell unit21has one column of the cells or two columns of the cells. And the number of the columns of the cells in the cell unit21is arbitrary.

FIGS. 7A to 7Dillustrate an operation explanatory diagram of the cell unit. For instance, as illustrated inFIG. 7, the three library apparatuses are stacked vertically in three stages, namely a lower stage, a middle stage and an upper stage. When the library apparatuses1are stacked, the library apparatuses1are stacked so that the openings41of two adjacent library apparatuses1are adjacent to each other and the positions of the openings41coincide with each other. And, the two adjacent library apparatuses1are positioned by a pin and coupled with a screw. At this time, the plate for covering the opening41is removed so as to allow the cell unit21of the library apparatus1to move between the library apparatuses1.

For instance, the library apparatus1placed in the lower stage (hereinafter called “lower library apparatus1A”) is connected with the host51. The library apparatus1placed in the middle stage (hereinafter called “middle library apparatus1B”) and the library apparatus1placed in the upper stage (hereinafter called “upper library apparatus1C”) are connected with each other, and also connected with the lower library apparatus1A.

The host51may issue an instruction to the lower library apparatus1A. For instance, the instruction is a instruction for reading data from the storage medium10stored in the cell5of the lower library apparatus1A using the drive unit3of the upper library apparatus1C. The storage medium and the drive unit are specified by the host51.

In this case, first of all, the lower library apparatus1A transmits information of the specified the drive unit3and instruction information for reading data from the specified storage medium10to the upper library apparatus1C. The host51manages the drive unit3and the storage medium10.

Therefore, the specified storage medium10is transported from the lower library apparatus1A to the specified drive unit3of the upper library apparatus1C via the middle library apparatus1B. First of all, the robot7of the lower library apparatus1A removes the specified storage medium10from the cell5, and stores the specified storage medium10into the uppermost cell5of the cell unit21of the lower library apparatus1A as illustrated inFIG. 7A. Next, the cell unit21of the middle library apparatus1B moves up and a portion of the cell unit21of the middle library apparatus1B enters into the space42. Then, the cell unit21of the lower library apparatus1A moves up and a portion of the cell unit21of the lower library apparatus1A enters into the space43in the middle library apparatus1B, and the uppermost cell5of the cell unit21of the lower library apparatus1A is located at a position accessible by the robot7of the middle library apparatus1B.

Next, the robot7of the middle library apparatus1B removes the specified storage medium10from the uppermost cell5of the cell unit21of the lower library apparatus1A as illustrated inFIG. 7B. Next, the cell unit21of the lower library apparatus1A moves down to return to a normal position. The normal position is a position that the robot7can access to all of the cells5. Then, the cell unit21of the middle library apparatus1B moves down and a portion of the cell unit21of the middle library apparatus1B enters into the space43in the middle library apparatus1B. Then, the cell unit21of the upper library apparatus1C moves down and a portion of the cell unit21of the upper library apparatus1C enters into the space42in the middle library apparatus1B. And the lowermost cell5of the cell unit21of the upper library apparatus1C is located at a position accessible by the robot7of the middle library apparatus1B. Then, the robot7of the middle library apparatus1B transports up the specified storage medium10which is removed from the lower library apparatus1A. And the specified storage medium10is located at a position for accessing the lowermost cell5of the cell unit21of the upper library apparatus1C.

And, as illustrated inFIG. 7C, the robot7of the middle library apparatus1B stores the specified storage medium10that is removed from the lower library apparatus1A into the lowermost cell5of the cell unit21of the upper library apparatus1C. Next, as illustrated inFIG. 7D, the cell unit21of the upper library apparatus1C moves up and the lowermost cell5is located at a position accessible by the robot7of the upper library apparatus1C. At this time, the middle library apparatus1B moves up to return to a normal position. The normal position is a position that the robot7can access to all of the cells5. The robot of the upper library apparatus1C removes the specified storage medium10at the lowermost position of the cell unit21of the upper library apparatus1C and transports the removed storage medium10to the specified drive unit3of the upper library apparatus1C. And, the upper library apparatus1C reads data from the storage medium10, and transmits the read data to the lower library apparatus1A via the communication controller35of the upper library apparatus1C. The lower library apparatus1A transmits the received data to the host51.

As described above, while space for cells5and space for drive units3are held equal to that of a conventional library apparatus which does not include a medium transportation mechanism by using the space42and the space43, the medium transportation mechanism that transports the storage medium10between the library apparatuses1may be realized. In this description, the uppermost cell5and the lowermost cell5are used to transport the storage medium10between the stacked library apparatuses1. A plurality of the cells5that includes the cells5such as the second-to-the uppermost cell5and the second-to-the lowermost cell5may be used depending on the size of the space42and the size of the space43. In this description, the cell unit21is provided at one side in the housing12. However the cell units21may be provided at both sides in the housing12, and may move up and down concurrently. Moreover, the cell units21of the library apparatuses1may move up and down concurrently by synchronizing with each other. Moreover, the storage medium10may be stored in the uppermost cell5of the middle library apparatus1B, and the cell unit21of the middle library apparatus1B may move up to the upper library apparatus1C.

Next, a transportation processing is described in detail, which is a processing that the lower library apparatus1A, the middle library apparatus1B and the upper library apparatus1C transport the storage medium10. For instance, the storage medium10specified by the host51is transported from the lower library apparatus1A to the drive unit3of the upper library apparatus1C specified by the host51. The uppermost cell5and the lowermost cell5are preliminarily determined as the cells5that are temporarily stored to transport the storage medium10. However depending on the size of the space, the cells5other than both of uppermost cell5and the lowermost cell5may be used as the cells5for transporting the storage medium10. Moreover, information of the specified the drive unit3and instruction information for reading data from or writing data into the specified storage medium10are transmitted from the lower library apparatus1A.

FIGS. 8A and 8Billustrate a flow chart of a lower library apparatus1A.FIG. 8Aillustrates step S1to step S3. A processing of the lower library apparatus1A is controlled by the CPU31of the lower library apparatus1A. In step S1, the lower library apparatus1A stores the storage medium10specified by the host51into the uppermost cell5. In step S2, the lower library apparatus1A instructs the middle library apparatus1B to move up the cell unit21of the middle library apparatus1B. The identification number of the specified storage medium10is given to the middle library apparatus1B. In step S3, the lower library apparatus1A checks whether to receive notification of the movement completion from the middle library apparatus1B.FIG. 8Billustrates step S4to step S8. In step S4, when the notification of the movement completion is received from the middle library apparatus1B, the lower library apparatus1A moves up the uppermost cell5of the cell unit21of the lower library apparatus1A to the position where the specified storage medium10in the uppermost cell5is accessible by the robot7of the middle library apparatus1B. In step S5, when the movement of the cell unit21of the lower library apparatus1A is completed, the lower library apparatus1A notifies the middle library apparatus1B of completion of the movement processing. In step S6, the lower library apparatus1A checks whether to receive completion notification of the removing processing of the specified storage medium10from the middle library apparatus1B. In step S7, when the lower library apparatus1A receives the completion notification of the removing processing of the specified storage medium10from middle library apparatus1B, the cell unit21of the lower library apparatus1A is moved down to return to the normal position. In step S8, the lower library apparatus1A notifies the middle library apparatus1B of completion of the movement processing.

FIGS. 9A to 9Dillustrate a flow chart of a middle library apparatus1B.FIG. 9Aillustrates step S11to step S14. A processing of the middle library apparatus B is controlled by the CPU31of the middle library apparatus1B. In step S11, the middle library apparatus1B receives the movement instruction from the lower library apparatus1A. In step S12, the middle library apparatus1B moves the cell unit21up into the space42of the middle library apparatus1B to retract the cell unit21. In step S13, the middle library apparatus1B notifies the lower library apparatus1A of completion of the movement processing when the movement is completed. In step S14, the middle library apparatus1B checks whether to receive notification of the movement completion from the lower library apparatus1A.FIG. 9Billustrates step S15to step S17. In step S15, when the notification of the movement completion is received from the lower library apparatus1A, the middle library apparatus1B removes the specified storage medium10which is stored in the uppermost cell5of the cell unit21of the lower library apparatus1A. In step S16, the middle library apparatus1B notifies the lower library apparatus1A of completion of the removing processing of the storage medium10. In step S17, the middle library apparatus1B checks whether to receive notification of the movement completion from the lower library apparatus1A.

FIG. 9Cillustrates step S18to step S20. In step S18, the middle library apparatus1B moves the cell unit21down into the space43to retract the cell unit21when the notification of the movement completion is received from the lower library apparatus1A. In step S19, when the movement of the cell unit21of the middle library apparatus1B is completed, the middle library apparatus1B instructs the upper library apparatus1C to move down. In step S20, the middle library apparatus1B checks whether to receive notification of the movement completion from the upper library apparatus1C.FIG. 9Dillustrates step S21to step S24. In step S21, when the notification of the movement completion is received from the upper library apparatus1C, the middle library apparatus1B stores the storage medium10in the lowermost cell5of the cell unit21of the upper library apparatus1C. In step S22, the middle library apparatus1B notifies the upper library apparatus1C of completion of the storing processing of the storage medium10. In step S23, the middle library apparatus1B checks whether to receive completion notification of the removing processing of the storage medium10from upper library apparatus1C. In step S24, the middle library apparatus1B moves the cell unit21up to return to the normal position, when the completion notification of the removing processing of the storage medium10is received from the upper library apparatus1C.

FIGS. 10A and 10Billustrate a flow chart of an upper library apparatus1C.FIG. 10Aillustrates step S31to step S34. A processing of the upper library apparatus1C is controlled by the CPU31of the upper library apparatus1C. In step31, the upper library apparatus1C checks whether to receive the movement instruction from the middle library apparatus1B. In step32, when the movement instruction is received from the middle library apparatus1B, the upper library apparatus1C moves the cell unit21down to the position where the lowermost cell5of the cell unit21of the upper library apparatus1C is accessible by the robot7of the middle library apparatus1B. In step33, the upper library apparatus1C notifies the middle library apparatus1B of completion of the movement processing when the movement of the cell unit21of the upper library apparatus1C is completed.

In step S34, the upper library apparatus1C checks whether to receive completion notification of the storing processing of the storage medium10from the middle library apparatus1B.

In step S35, when the completion notification of the storing processing of the storage medium10is received from the middle library apparatus1B, the upper library apparatus1C moves up the cell unit21of the upper library apparatus1C to a normal position. The normal position is a position that the robot7can access to all of the cells5.

In step S36, the upper library apparatus1C removes the storage medium10from the lowermost cell5of the cell unit21of the upper library apparatus1C.

In step S37, the upper library apparatus1C notifies the middle library apparatus1B of completion of the removing processing of the storage medium10. In step S38, the upper library apparatus1C loads the storage medium10in the specified drive unit3. As a result, the transportation processing of the storage medium10from the lower library apparatus1A to the upper library apparatus1C is completed. The upper library apparatus1C writes data into or read data from the storage medium10, when the transportation processing is completed. When the instruction from the host51is to read the data from the storage medium10, the upper library apparatus reads the data from the storage medium10and transmits the data to the lower library apparatus1A. When the lower library apparatus1A receives the data, the lower library apparatus1A transmits the data to the host51. On the other hand, when the instruction from the host51is to write the data into the storage medium10, the upper library apparatus acquires the data of the host51from the lower library apparatus1A and writes the data into the storage medium10. When the read processing or the write processing is completed, the storage medium10is transported from the upper library apparatus1C to the lower library apparatus1A via a reverse route.

As described above, since the library apparatus1transports the storage medium10to other library apparatus1by moving the cell unit21, the library apparatus1does not include a new medium transportation mechanism that occupies partially area of the cell5and area of the drive unit3. The number of the storage mediums10in the cells5is prevented from decreasing. Namely, it is not needed that the number of the cells5or the number of the drive units3is decreased to secure area and that a new transportation mechanism is provided by using the secured area.

Moreover, there is no need for providing the medium transportation mechanism of the storage medium10as a separated unit. Therefore, the installation of an additional library apparatus1is facilitated.