Library device and inclination correction method of movable unit provided in library device

A library device includes: a storage shelf including storage units aligned in a plurality of columns; and a conveying robot that grasps and conveys cartridges stored in the storage units, wherein the conveying robot includes: a base board located to face the plurality of columns, one end of the base board being supported movably up and down by a first support post, and another end of the base board being supported movably up and down by a second support post; a movable unit including a grasping unit grasping the cartridges stored in the storage units and moving on the base board; an inclination measuring unit measuring an inclination of the movable unit; and an inclination correction unit adjusting heights of both ends of the base board according to an inclination value of the movable unit measured by the inclination measuring unit and correcting the inclination of the movable unit.

FIELD

A certain aspect of the embodiments discussed herein is related to a library device and an inclination correction method of a movable unit provided in a library device.

BACKGROUND

A grasping unit provided with a hand unit is used when conveying magnetic tape cartridges and optical cartridges (hereinafter, referred to as cartridges) in a magnetic tape library device. The grasping unit moves up, down, right and left, and transfers cartridges between an intended storage unit and a cartridge drive device.

The grasping unit determines a storage unit storing a cartridge to be conveyed, moves to the front of the storage unit, makes the hand unit grasp the cartridge, and carries out the transfer of the cartridge.

At this time, it is desired that the hand unit is positioned properly to the target cartridge. Conventionally, various approaches of positioning such a hand unit have been proposed. For example, a correction method of a position data and an object position determination system have been known as related arts to determine or correct the position of the conveying robot (see. Japanese Laid-Open Patent Publication Nos. 5-342723 and 2000-314611).

SUMMARY

According to an aspect of the present invention, there is provided a library device including: a storage shelf that includes storage units aligned in a plurality of columns; and a conveying robot that grasps and conveys cartridges stored in the storage units, wherein the conveying robot includes: a base board that is located to face the plurality of columns, one end of the base board being supported movably up and down by a first support post, and another end of the base board being supported movably up and down by a second support post; a movable unit that includes a grasping unit that grasps the cartridges stored in the storage units and moves on the base board; an inclination measuring unit that measures an inclination of the movable unit; and an inclination correction unit that adjusts heights of both ends of the base board according to an inclination value of the movable unit measured by the inclination measuring unit and corrects the inclination of the movable unit, each of the first support post and the second support post includes a part where a first engage portion is formed that is engaged with a second engage portion provided to the base board and supports the base board, and the inclination correction unit includes a first motor that drives the first support post and a second motor that drives the second support post.

DESCRIPTION OF EMBODIMENTS

As described previously, methods of determining or correcting the position of the conveying robot have been proposed. The grasping unit is located on a base board which is movable up and down, and moves horizontally on this base board. The grasping unit includes various devices, and has a certain weight. When such grasping unit moves on the base board, the base board bends. If the base board bends, the grasping unit on the base board inclines. The degree of inclination depends on the position of the grasping unit on the base board. If the grasping unit inclines, it becomes difficult for the hand unit to grasp a cartridge to be grasped.

In order to prevent such a situation, it is considered to make the thickness of the base board thicker, or to use a material of which a flexural rigidity and the like is high.

However, recently, a downsizing and density growth of the product are enhanced, and it is difficult to make the thickness of the base board thicker. In addition, the use of the material with high flexural rigidity leads an increase of the product cost, and impedes the cost reduction.

In related arts disclosed in Japanese Laid-Open Patent Publication Nos. 5-342723 and 2000-314611, it is not considered to correct the inclination of the grasping unit.

A description will now be given of embodiments of the present invention with reference to accompanied drawings. In drawings, the size, the ratio and the like of each unit are not illustrated to correspond to actual portions completely. In addition, in several drawings, detail illustration may be omitted.

First Embodiment

FIG. 1is an explanatory diagram illustrating a schematic structure of a library device100in accordance with a first embodiment.FIG. 2is an explanatory diagram of the library device100viewed from overhead.FIG. 3is an explanatory diagram illustrating a state where a second storage shelf15is removed from the library device100.FIG. 4is an explanatory diagram illustrating a state where a movable unit50is moved to the front of a second column12, and directed toward a first flag31.FIG. 5is an explanatory diagram illustrating a state where the movable unit is moved to the front of the second column12, and directed toward a second flag32.

The library device100includes a chassis1. A three-dimensional coordinate system, namely an xyz-coordinate system, is defined in the inner space of the chassis1as illustrated inFIG. 3. The x-direction of the xyz-coordinate system corresponds to an alignment direction of columns included in a first storage shelf10and the second storage shelf15. That is to say, the x-direction extends in the horizontal direction in parallel with the first storage shelf10and the second storage shelf15. The y-direction is perpendicular to the x-direction, and extends in the horizontal direction. The z-direction is a vertical direction.

The library device100is provided with a cartridge drive device20where data in a cartridge2is loaded. The library device100includes storage shelves10and15having storage units11aand so on which are aligned in multiple columns. More specifically, the first storage shelf10and the second storage shelf15are provided in the chassis1. The first storage shelf10includes a first column11formed by stacking storage units11avertically, and the second column12formed by stacking storage units12avertically. In addition, the first storage shelf10includes a third column13formed by stacking storage units13avertically, and a fourth column14formed by stacking storage units14avertically. The first column11through the fourth column14are aligned along the x-direction. The second storage shelf15is located to face the first storage shelf10. The second storage shelf15includes a fifth column16, a sixth column17, a seventh column18, and an eighth column19formed in the same manner as the first storage shelf. The fifth column16through the eighth column19are aligned along the x-direction.

The first flag31and the second flag32are provided to storage units11aand14aincluded in the first column11and the fourth column14which are located on the both sides of the first storage shelf10respectively. More specifically, the first flag31is provided to the storage unit11alocated at a bottom row of the first column11, and the second flag32is provided to the storage unit14alocated at a bottom row of the fourth column14.

The library device100is further provided with a conveying robot110that grasps and conveys cartridges2stored in storage units11aand so on.

The conveying robot110includes a base board40, the movable unit50, a first support post41, and a second support post45. More specifically, the conveying robot110includes the base board40which is located to face multiple columns included in the first storage shelf10and the second storage shelf15, one end of the base board40is supported movably up and down by the first support post41, and the other end of the base board40is supported movably up and down by the second support post45.

The conveying robot110is further provided with the movable unit50which reciprocates on the base board40. In addition, the conveying robot110includes an inclination correction unit that adjusts the heights of both sides of the base board40according to the inclination value of the movable unit50measured by an inclination measuring unit described later and corrects the inclination of the movable unit50.

A description will now be given of the movable unit50.FIG. 6andFIG. 7are explanatory diagrams illustrating a schematic structure of the movable unit50. As illustrated inFIG. 6andFIG. 7, the movable unit50includes a grasping unit54that grasps cartridges2stored in storage units11aand so on.

The grasping unit54includes a pair of unguiform arms projecting forward from a base51. Locking protrusions54aare provided to tip portions of arms. The grasping unit54opens and closes between a first position and a second position. In the first position, arms are away from each other at a first distance in a horizontal direction. In the second position, arms are away from each other at a second distance greater than the first distance in the horizontal direction. When the grasping unit54is in the first position, the cartridge2is grasped between locking protrusions54a. When locking protrusions54aare placed at the second position, a space that allows a transfer of the cartridge2is secured between locking protrusions54a. As described above, the cartridge2is grasped by the grasping unit54. So-called rack-and-pinion mechanism may be used as the opening/closing mechanism of the grasping unit for example. An arbitrary power source may be connected to a pinion of the rack-and-pinion mechanism. An electric motor is mutually used for pinions as a power source. A stepping motor may be used for such a grasping mechanism electric motor for example.

The grasping unit54moves forward with being opened as illustrated inFIG. 8so that locking protrusions54aare coincident with positions of locking grooves2aprovided to the cartridge2stored in the first storage shelf10. Then, the grasping unit54grasps the cartridge2by being closed so that locking protrusions54aare locked to locking grooves2aas illustrated inFIG. 9.

A printed substrate52is mounted on the base51of the movable unit50. The printed substrate52expands along the horizontal surface. A line CCD (a charge-coupled device)53is implemented to the surface of the printed substrate52. The line CCD53corresponds to a capturing unit in accordance with a present invention, and is included in an inclination measuring unit of the present invention. In the line CCD53, pixels are aligned in one column in the horizontal direction. For example, in the line CCD53, at least black or white can be determined in each pixel. The line CCD53receives lights from the vertical direction against the surface of the printed substrate52.

In the movable unit50, a target space58expanding in the horizontal direction in front of the base51is defined. An optical path is established between the target space58and the line CCD53. A collective lens55is provided above the printed substrate52to establish the optical path. An object in the target space58is focused on the line CCD53by the function of the collective lens55.

An LED (light emitting diode) lamp56is mounted on the surface of the printed substrate52. The LED lamp56is provided with LED elements which are aligned in the horizontal direction, namely an LED array. The LED lamp56emits light to the target space58. Accordingly, the target space58is lighted up by the light.

As is clear fromFIG. 7, a reflecting mirror57is provided above the printed substrate52to establish the optical path. The optical path is refracted to a right angle by the reflecting mirror57. The light is guided to the horizontal direction from the target space58to the reflecting mirror57. The light is collected by the lens55before entering the reflecting mirror57. The reflection light of the reflecting mirror57reaches the line CCD53. The reflecting mirror57may be supported by an arbitrary supporting member (not illustrated) to be located above the printed substrate52.

The line CCD53captures the object located in the target space58. For example, when the cartridge2is grasped by the grasping unit54, a barcode label on the cartridge2is placed in the target space58. The barcode label is read by the line CCD53. The line CCD53reads the first flag31and the second flag32described in detail later.

A description will now be given of the first flag31. As the second flag32is same as the first flag31, a description will be omitted.

As illustrated inFIG. 10, the first flag31is provided with a flat surface68which is a black surface indicated by a hatching inFIG. 10. A center line67is defined on the flat surface68. The flat surface68is divided into a first region61on the left side and a second region62on the right side by the center line67. The first and second regions61and62contact with each other at the center line67. Color-coded patterns are drawn symmetrically from the center line67.

The color-coded patterns include a median zone63which is white and extends to the vertical direction on the center line67. The median zone63is separated by a pair of center indication lines64extending in the vertical direction in parallel with the center line67. In the same manner, the color-coded patterns include a matched pair of white side zones65aand65bextending in the vertical direction in the first and second regions61and62. Each of side zones65aand65bis separated by a pair of auxiliary indication lines66aand66bextending in the vertical direction in parallel with the center line67. In side zones65aand65b, auxiliary indication lines66bcorrespond to the right and left ends of the first flag31. Here, a distance Wd between the left side zone65aand the median zone63is equal to a distance Dw between the median zone63and the right side zone65b. The distance between auxiliary indication lines66aand66band the distance between center indication lines64are set to the same value.

The color-coded patterns include white isosceles right triangles69and69in the first and the second regions61and62respectively. The isosceles right triangle69in the first region61has a hypotenuse69afrom top left to bottom right. The isosceles right triangle69in the second region62has a hypotenuse69bfrom top right to bottom left. In either of isosceles right triangles69, one of equal sides is located in parallel with the center line67. The other of equal sides is located on the line perpendicular to the center line.

When the first flag described above is captured by the line CCD53which inclines, the length of line segment of each portion varies. The line CCD53is mounted on the movable unit50, but the movable unit50inclines because of the deflection of the base board40caused by the move of the movable unit50on the base board40. As a result, the line CCD53inclines. The image of the first flag31captured by the line CCD53varies according to the degree of the inclination of the movable unit50. In the same manner, the image of the second flag32varies according to the degree of the inclination of the movable unit50. Thus, the inclination of the movable unit50can be measured by analyzing the image information obtained by the line CCD53. As described above, the line CCD53measuring the inclination of the movable unit50is included in the inclination measuring unit of the present invention.

FIG. 11is a block diagram illustrating schematic configurations of a library control board and a control board. As illustrated inFIG. 11, a control board119is coupled to the conveying robot110. A CPU (Central Processing Unit)120is implemented to the control board119. A RAM (Random Access Memory)121and a non-volatile memory122are coupled to the CPU120. A flash memory may be used as the non-volatile memory122for example.

Software programs123and position data124are stored in the non-volatile memory122. The position data124specifies the position of the opening of each of storage units11a,12aand so on. The CPU120executes given procedures according to software programs123and the position data124loaded to the RAM121temporarily for example.

A y-axis motor111, a first z-axis motor44, a second z-axis motor48, an x-axis motor112, a revolution electric motor113, and a grasping mechanism motor114which are incorporated in the conveying robot110are coupled to the CPU120. The CPU120provides drive signals to these motors. Each of motors111,44,48,112,113, and114rotates at the rotational amount specified based on the drive signal. The move and the revolution of the movable unit50and the grasping operation of the grasping unit54are determined by the rotational amounts of these motors.

The line CCD53described previously and an LED driver118are coupled to the CPU120. The black/white determination signal of each pixel is provided to the CPU120from the line CCD53. The LED driver188makes the LED lamp56emit the light. When the LED lamp56emits the light, the drive signal is provided to the LED lamp56from the LED driver118. The light emission of the LED lamp56is controlled based on the control signal provided to the LED driver118from the CPU120.

A non-volatile memory115is further incorporated in the conveying robot110. The non-volatile memory115stores inclination correction data116for each of columns11,12and so on. The inclination correction unit correcting the inclination of the movable unit50functions based on the inclination correction data116.

The control board119is coupled to a library control board125. The library control board125is provided with a CPU126, a RAM127and a non-volatile memory128for example. Software programs129are stored in the non-volatile memory128. The CPU126executes given procedures according to software programs129loaded to the RAM127temporarily for example. The library control board125is coupled to a host computer.

A description will now be given of the inclination correction unit that corrects the inclination of the movable unit50. The conveying robot110is provided with the base board40, the movable unit50, the first support post41, and the second support post45as described above. More specifically, it is provided with the base board40which is located to face multiple columns included in the first storage shelf10and the second storage shelf15. One end of the base board40is supported movably up and down by the first support post41, and the other end of the base board40is supported movably up and down by the second support post45. As described above, the inclination of the movable unit50is corrected by adjusting the height of the end portion of the base board40supported by the first support post41and the height of the end portion of the base board40supported by the second support post45.

Hereinafter, a description will be given of a practical mechanism to adjust heights of end portions of the base board40.

The conveying robot110is provided with the first support post41and the second support post45stood on the floor surface of the chassis1rotatably. Screw threads are formed on the surface of the first support post41, and are engaged with a screw portion40aprovided to the base board40. The first support post41includes a first pulley42in its bottom end portion, and a first belt43is stretched between the first pulley42and the first z-axis motor44. According to this, when the first motor44rotates, the first support post41is rotated, and the height adjustment of the one end of the base board40can be carried out. In addition, screw threads are formed on the surface of the second support post45in the same manner as the first support post41, and are engaged with a screw portion40bprovided to the base board40. The second support post45includes a second pulley46in the bottom end portion, and a second belt47is stretched between the second pulley46and the second z-axis motor48. According to this, when the second motor48rotates, the second support post45is rotated, and the height adjustment of the other end of the base board40can be carried out.

A description will now be given of a method of correcting the inclination of the movable unit50in the conveying robot110described above.

The method of correcting the inclination of the movable unit50includes an inclination measuring process that measures the inclination value with respect to each of columns11,12and so on included in the first storage shelf10and the second storage shelf15. Moreover, it includes a correction value setting process that calculates correction values of heights of one end and/or the other end with respect to each of columns11,12and so on based on the inclination value measured in the inclination measuring process. Furthermore, it includes a height adjustment process that adjusts heights of one end and/or the other end of the base board40according to correction values calculated in the correction value setting process. Hereinafter, each process is described with reference to a flowchart.

A description will now be given of an inclination measuring process with reference to a flowchart illustrated inFIG. 12.

In the inclination measuring unit, the movable unit50is moved to the front of the column to be measured, and the first flag31provided to the storage unit11aincluded in the first column11and the second flag32provided to the storage unit14aincluded in the fourth column14are captured. The line CCD53provided to the movable unit50captures the first flag31and the second flag32. The inclination value is obtained based on the acquired image information.

In a step S1, “1” is assigned as a column so as to set the first column as the column to be measured. Then, in a step S2, the movable unit50is moved in front of the column to be measured. At first, the movable unit50is moved to the front of the first column11. At this time, the vertical position of the movable unit50, which means the position in the z-direction, is set to the position where the movable unit50can read the first flag31and the second flag32. More specifically, it becomes a position coincident with the storage unit11alocating at a bottom row.

In a step S3subsequent to the step S2, the movable unit50is rotated as illustrated inFIG. 4, and the line CCD53mounted in the movable unit50is directed toward the first flag31.FIG. 4illustrates a state where the second column12is a column to be measured and the movable unit50is directed toward the first flag31.

In the step S4, the first flag31is captured by the line CCD53, the obtained captured image is analyzed, and the measured value is obtained and recorded.

Then, in a step S5, as illustrated inFIG. 5, the movable unit50is rotated, and the line CCD53mounted on the movable unit50is directed toward the second flag32.FIG. 5illustrates a state where the second column12is a column to be measured and the movable unit50is directed toward the second flag32.

In a step S6, the second flag32is captured by the line CCD53, the obtained captured image is analyzed, and a measured value is acquired.

With above procedures, a measurement for one column is completed, and the inclination value when the movable unit50is placed in front of the column to be measured can be obtained.

In a step S7, “column+1” is assigned to the column so as to set the next column as the column to be measured. For example, the second column12is set as the column to be measured next to the first column11. In a step S8, it is determined whether the measurements for columns to be measured are completed. In this embodiment, as the measurement will be continued till the fourth column14, procedures from the step S2to the step S7are repeated till the measurement for the fourth column14is completed. When the column exceeds four in the step S8, the process is ended.

The library device100may measure all columns because it includes the first column11through the eighth column19. As the first column11is located in the position facing the fifth column16, the position of the movable unit50on the base board40becomes same. This is applied to other columns as well. Therefore, in this embodiment, an inclination measurement is carried out to only the first storage shelf10.

A description will now be given of a correction value setting process with a reference to a flowchart illustrated inFIG. 13.

In the step S11, “column1” is set to specify the first column11as the column for the correction value setting. In a step S12, the measured value obtained and recorded by capturing the first flag31in the step S4of the flowchart illustrated inFIG. 12is set as the correction value to the first motor44. For example, when the measured value is +1 mm, the actual position of the movable unit50is −1 mm against the nominal position. Thus, +1 mm is set as the correction value.

In a step S13, a measured value obtained and recorded by capturing the second flag32in the step S6of the flowchart illustrated inFIG. 12is set as the correction value for the second motor48. For example, when the measured value is −3 mm, the actual position of the movable unit50is +3 mm against the nominal position. Thus, −3 mm is set as the correction value.

Then, in a step S14, “column+1” is set as the column as to set the next column as the column for the correction value setting. For example, the second column12is set as the column for the correction value setting next to the first column11. In a step S15, it is determined whether the setting of the correction value is completed to the column to be measured. In this embodiment, as the measurement is carried out till the fourth column14, procedures from the step S12through the step S14are repeated till the setting of the correction value for the fourth column14is completed. In the step S15, when it is determined that the column exceeds four, the process is ended.

A description will now be given of a height adjustment process with reference to a flowchart illustrated inFIG. 14.

In the conveying robot110of the first embodiment, the first support post41and the second support post45supporting end portions of the base board40are rotated by the first motor44and the second motor48respectively. Thus, the height adjustments according to the correction values can be carried out simultaneously with the move toward target storage units11a,12aand so on. That is to say, the drive commands are supplied to the first motor44and the second motor48so that the first support post41and the second support post45are always moved upward or downward by the amounts calculated by adding correction values to nominal values of the storage unit11a,12aand so on. That is to say, the lifting amount is adjusted according to the flexural amount of the base board40.

According to the processes described above, the correction of inclination of the movable unit50is carried out according to the position of the movable unit50. According to this, the inclination of the grasping unit54provided to the movable unit50is corrected. As a result, the inclination of the movable unit50on the base board40where the flexure occurs is corrected appropriately, and the cartridge2can be grasped by the grasping unit54.

Second Embodiment

A description will now be given of a second embodiment with reference toFIG. 15throughFIG. 27.

A library device200in accordance with the second embodiment is provided with a conveying robot210instead of the conveying robot110provided to the library device100of the first embodiment. The conveying robot210is provided with the inclination correction unit that corrects the inclination of the movable unit50in the same manner as the conveying robot110. The conveying robot210includes the base board40, the movable unit50, the first support post41, and the second support post45. More specifically, it includes the base board40which is located to face the multiple columns included in the first storage shelf10and the second storage shelf15. One end of the base board40is supported movably up and down by the first support post41, and the other end of the base board40is supported movably up and down by the second support post45. As described, the inclination of the movable unit50is corrected by adjusting the height of the end portion of the base board40supported by the first support post41and the height of the end portion of the base board40supported by the second support post45. These are same as the conveying robot110of the first embodiment. However, the mechanism of adjusting heights of end portions of the base board40is different from each other. Hereinafter, a description will be given of the second embodiment focusing on the difference from the first embodiment. Same reference numerals are assigned to components common with the first embodiment, and the detail description of them is omitted.

FIG. 15is an explanatory diagram illustrating a schematic structure of the library device200in accordance with the second embodiment.FIG. 16is an explanatory diagram illustrating a state where the second storage shelf15is removed from the library device200.FIG. 17is an explanatory diagram illustrating the state where the movable unit50is moved to the front of the second column, and directed toward the first flag31.FIG. 18is an explanatory diagram illustrating the state where the movable unit50is moved to the front of the second column, and directed toward the second flag32. As is clear from these figures, in the conveying robot210, the first support post41and the second support post45are rotated by a single motor213.

Hereinafter, a description will be given of a practical mechanism of adjusting heights of end portions of the base board40. The conveying robot210is provided with the first support post41and the second support post45stood on the floor surface of the chassis1rotatably. Screw threads are formed on the surface of the first support post41, and are engaged with the screw portion40aprovided to the base board40. The first support post41is provided with the first pulley42to a bottom end portion. Screw threads are formed on the surface of the second support post45in the same manner as the first support post41, and are engaged with the screw portion40bprovided to the base board40. The second support post45is provided with the second pulley46to the bottom end portion.

The motor213rotating the first support post41and the second support post45is located to the side near the second support post45. A power transmitting unit230which includes a switching unit capable of switching the transmission state of the power of the motor213to the second support post45is located to the side near the second support post45.

The power transmitting unit230is provided with a link mechanism230a, a first gear214, and a second gear215as illustrated inFIG. 20andFIG. 21. The link mechanism230aillustrated inFIG. 19corresponds to a switching unit of the present invention, and includes a switching member217that operates by the move of the movable unit50, and a third gear220that moves in conjunction with the switching member217and is a connecting member that connects the motor213and the second support post45.

More specifically, a protrusion217aprovided to the switching member217is engaged with a first engagement hole218aprovided to a first arm member218. An engagement protrusion219aprovided to a second arm member219is engaged with a second engagement hole218bprovided to the first arm member218. The third gear220is mounted on the end portion of the second arm member219rotatably. The second arm member219is rotatably mounted on a seat221fixed to the floor surface of the chassis1via a pin22. A spring223that brings the second arm member219back to the original position is mounted between the seat221and the second arm member219. The switching member217is mounted so as to protrude to the top side of the base board40through the hole40aprovided to the base board40.

The first gear214is mounted on the floor surface of the chassis1rotatably. The first gear214engages with a pinion gear provided to the motor213. The first gear214is provided with a third pulley214ato its bottom end. A third belt211is stretched between the third pulley214aand the first pulley42provided to the bottom side of the first support post41via idle rings212aand212b. According to this, the first support post41is rotated, and the height adjustment of one end of the base board40can be carried out.

The second gear215is mounted on the floor surface of the chassis1rotatably. The second gear215is linked to the first gear214by engaging with the third gear220, and the rotation of the motor213is transmitted. The second gear215is provided with a fourth pulley215ato its bottom end. A fourth belt216is stretched between the fourth pulley215aand the second pulley46provided to the bottom side of the second support post45. According to this, the second support post45is rotated, and the height adjustment of the other end of the base board40is carried out.

Here, a description will now be given of the operation of the power transmitting unit230.FIG. 20is a perspective view of the power transmitting unit230in a state where the power can be transmitted.FIG. 21is a perspective view of the power transmitting unit230in a state where the power is not transmitted.FIG. 22is an explanatory diagram of the vicinity of the power transmitting unit230which is incorporated in the library device200and is in a state where the power can be transmitted.FIG. 23is an explanatory diagram of the vicinity of the power transmitting unit230that is incorporated in the library device200and in a state where the power is not transmitted.FIG. 24is an explanatory diagram illustrating a state of the movable unit50when transferring a cartridge from the cartridge drive device20.

As illustrated inFIG. 22, when the movable unit50is away from the end portion on the second support post45side, the switching member217is leaned forward as illustrated inFIG. 20. At this time, the second arm member219is biased by the spring223, and moves the third gear220to the direction where it engages with the first gear214and the second gear215. According to this, the rotation of the motor213is transmitted to the first gear214, the third gear220, and the second gear215in this order. As a result, the fourth pulley215ais rotated, and the second support post45is rotated by the fourth belt216. That is to say, when the second support post45is desired to be rotated, the movable unit50is kept at the position where the switching member217is not pressed.

On the other hand, as illustrated inFIG. 23, when the movable unit50approaches the end portion of the second support post45and presses the switching member217, the switching member217is leaned back as illustrated inFIG. 21. At this time, the second arm member219is rotated around a pin222withstanding the force of the spring233, and moves the third gear220away from the first gear214and the second gear215. According to this, the transmission of the rotation of the motor213to the second gear215is cut off. That is to say, when the rotation of the second support post45is desired to be stopped, the movable unit50is moved to the position where the switching member217is pressed.

FIG. 25is a block diagram illustrating schematic configurations of the library control board and the control board provided to the library device200. Configurations are same as the library device100of the first embodiment except that the number of the z-axis motor is one.

A description will now be given of a method of correcting the inclination of the movable unit50in the conveying robot210described above. The method of correcting the inclination of the movable unit50includes an inclination measuring process that measures the inclination value with respect to each of columns11,12and so on included in the first storage shelf10and the second storage shelf15. In addition, it includes a correction value setting process that calculates correction values of the heights of one end and/or the other end of the base board40with respect to each of columns11,12and so on. Furthermore, it includes a height adjustment process that carries out the height adjustment of one end and/or the other end of the base board40according to the correction values calculated in the correction value setting process. These are same as the conveying robot110of the first embodiment. As the inclination measuring process is same as the process described with the flowchart inFIG. 12, a detail description will be omitted. Hereinafter, the correction value setting process and the height adjustment process will be described.

A description will be given of the correction value setting process with reference to the flowchart illustrated inFIG. 26.

In a step S31, “column1” is set to specify the first column11as the column for the correction value setting. In a step S32, the measured value obtained by capturing the second flag32in the step S6illustrated inFIG. 12is subtracted from the measured value obtained by capturing the first flag31in the step S4illustrated inFIG. 12. And the value calculated from the subtraction is set as the correction value.

Then, in a step S33, “column+1” is set as a column so as to set the next column as the column for the correction value setting. For example, the second column12is set as the column for the correction value setting next to the first column11. In a step S34, it is determined whether the setting of the correction value to the column to be measured is completed. In this embodiment, the measurement is carried out till the fourth column14, the procedures from the step32to the step33are repeated till the setting of the correction value for the fourth column14is completed. When it is determined that the column exceeds four in the step S34, the process is ended.

A description will now be given of a height adjustment process with reference to the flowchart illustrated inFIG. 27. In a step S41, the base board40is moved down to the lowermost position. According to this, the switching member217is exposed from the hole40aprovided to the base board40. In a step S42, the movable unit50is moved to the switching member217side. Then, in a step S43, the switching member217is pressed by the movable unit50, and the state illustrated inFIG. 23is achieved. According to this, the third gear220moves away from the first gear214and the second gear215. As a result, the rotation of the motor213is not transmitted to the second support post45.

In a step S44, the motor213is driven by the correction value of the target column, and the first support post41is rotated. According to this, the height of one end of the base board40is adjusted, and the inclination of the movable unit50is corrected. At this time, as the motor213can be rotated positively and negatively, the inclination of the movable unit50can be corrected regardless of the position of the base board40.

In the step S45, the movable unit50is moved forward. That is to say, the movable unit50is moved away from the switching member217to achieve the state illustrated inFIG. 22. According to this, the third gear220engages with the first gear214and the second gear215. As a result, the rotation of the motor213is transmitted to the second support post45. In a step S46, the motor213is driven by the nominal value corresponding to the column of the target storage unit.

With processes described above, the inclination of the movable unit50is corrected according to the position of the movable unit50. According to this, the inclination of the grasping unit54provided to the movable unit50is also corrected. As a result, the inclination of the movable unit50on the base board40where the flexure occurs is corrected properly, and the cartridge2can be grasped by the grasping unit54.

For example, library devices storing cartridges are described in above embodiments, but the present invention disclosed in this specification can be applied to library devices storing other objects.